Ubat kanser cara alami
Betulinic Acid for Skin Cancer
Update, and a mention of Santa Claus
December 21, 2006
Jacob Schor, ND
A year ago, I sent out a newsletter
on betulinic acid and its potential use in treating cancer, especially
melanoma. As it was almost Christmas when I sent it out, I managed a weak tie
in to some trivia about Santa Claus. It turns out that our image of this
generous gentleman may be a bit misplaced. Instead, I suggested that you
consider Santa from an anthropological viewpoint, as a commercialized
euphemistic representation of a mad eyed shaman of the reindeer people of the
far north, stumbling across the frozen tundra feeding hallucinogenic amanita
mushrooms to both his reindeer herds and his ‘congregation', dropping down the
smoke holes of yurts with a psychedelicized ho-ho-ho.
I enjoyed reading up on this history
and found it entertaining to contemplate when watching Santa Claus at the
shopping mall. So entertained was I that I decided to resend the same
newsletter out again this year.
My recent email on mistletoe and my
allusions to our current culture wars over wishing a Merry Christmas, generated
several requests from people asking to be removed from our mailing list. At
this point, we hopefully won't offend anyone else on the list by revealing
Santa's true identity.
First, we must look at new
developments regarding betulinic acid since this time last year. Recall that
betulinic acid is a chemical derived from Birch tree bark. A paper back in 1995
first suggested that betulinic acid might be useful in treating skin cancer.
Last year's Santa newsletter chronicled the early studies. So what is new? It
turns out that a lot is new.
In February 2006, a paper reported
great success using a topical salve containing betulinic acid to treat actinic
keratosis. Twenty-eight patients were treated with either betulinic alone or
betulinic acid in combination with standard freezing therapy. Clearing of more
than 75 % of the lesions was seen in 79 % of the patients treated with birch
bark ointment alone. The response rate of the combined treatment, betulinic
acid and freezing, was 93 %. [i]
Studies
are looking into the chemical structure of various betulinic derivatives
attempting to figure out which forms work best against which cancer types and,
more important to drug companies, which ‘analogues' that can be patented also
work. A study from May, details the variations on structure hoping to determine
which pieces are most needed to produce the substance's anticancer effect for
modeling chemotherapy drugs after. [ii] A study from September is already testing analogues to
betulinic acid to see if they work as well as the real stuff. [iii]
Half a
dozen or so other studies continue to pursue information on betulinic acid's
value in treating skin and other cancers. Betulinic acid kills other types of
cancer cells as well as melanoma.
In a
study published December 12, that is last week, Dutch researchers, “… tested
the in vitro sensitivity of broad cell line panels derived from lung,
colorectal, breast, prostate and cervical cancer, which are the prevalent
cancer types characterized with highest mortalities in woman and men.” Their
results were impressive: “….in all cell lines tested colony formation was
completely halted at remarkably equal BA concentrations that are likely
attainable in vivo.” [iv]
It was effective against all the cell lines tested in that
study but they stuck with the big cancers. Another study published earlier in
the year, suggests betulinic acid does not work against all types of Burkitt's
lymphoma, one of those obscure things you don't want to get. [v]
Other uses for
betulinic acid are showing up in the literature. It may be useful as an anti inflammatory
and in killing the HIV virus that causes AIDs. It still appears to be safe, it
is non toxic in mice in doses up to 500 mg per kilogram. [vi]
Last year I mentioned studies that showed that betulinic
acid augmented the anticancer effect of vitamin D on leukemia, vincristin on
lung cancer, hyperthermia and several other anticancer drugs. A study from
September 2005, which I hadn't noticed, reports that betulinic acid was helpful
when used in combination with vincristin for treating squamous cell cancers of
the head and neck. [vii]
Just in November, a
Chinese group reported a newer simpler and less expensive way to extract
betulinic acid. [viii] Back in January, an American company named NATURNORTH
TECHNOLOGIES near Duluth , Minnesota reported they had figured out a way to
make betulinic acid from waste materials leftover from paper manufacturing. [ix]
Despite this
interesting research, betulinic acid is still not widely available. I have yet
to see any of our major nutritional supplement suppliers offering it in capsule
or topical form. At this point, betulinic is available from chemical supply
houses at reasonable prices and we have the option of hand compounding it into
topical ointments or encapsulating it ourselves. Another option is to use Birch
bark which can contain as much as 30% betulin. This can be made into a tea or a
compress.
My imagination quickly
runs to the idea of steeping pounds of birch bark in a hot tub in which we then
soak patients. Given the apparent safety of the treatment and the current
prognosis for patients with melanoma, one has to ask, “Why not?”
I will paste our
original Santa newsletter below. You can read it with references on our
website: http://denvernaturopathic.com/news/santaandbetulinic.html
Santa Claus,
Hallucinogenic mushrooms, birch trees and melanoma
December 8, 2005
Subject: Betulinic acid
research is moving forward confirming its value in treating melanoma. Chaga
mushrooms may be even more useful. Santa Claus trivia as well.
It is time to review
the new studies on betulinic acid, a derivative of birch bark, and its
potential role in treating melanoma. It is also time to consider the use of
Chaga mushrooms which grow on birch trees. Yet given the season, we first must
consider Santa Claus and his reindeer as the subjects are connected.
Santa Claus and Amanita
Mushrooms:
Our dear Santa, despite
his modern association with Christmas, is apparently modeled after the shamans
of the reindeer culture of the far northern latitudes. These peoples and
especially their shamans relied on amanita mushrooms for their potent
hallucinogenic properties which proved efficacious for communing with the gods.
Amanita muscaria
mushrooms grow only under certain types of trees, mostly firs and evergreens.
Amanita are bright red with white spots: they are the original bright gifts
that these early people sought under their ‘Christmas' tree.
In the belief system of
these people, the sacred North Star stood atop a magical evergreen tree that
was the central axis of the world. The shaman would metaphorically climb this
tree and, by touching the North Star, would pass into the realm of the gods.
With enough hallucinogenic mushrooms, anything is possible.
There is a drawback.
Amanita mushrooms are very poisonous. They cause catastrophic liver failure.
Serious shamans could avoid violent death by slowly building up tolerance to
the poison by consuming tiny amounts of mushroom daily. Daily doses of
violently toxic hallucinogens have their drawbacks. You can't hold a day job.
For the peoples of the
far north reindeer provided an almost magical way around amanita toxicity.
Reindeer are unaffected by the toxins or hallucinogens in amanita. When
reindeer eat the mushrooms, the active hallucinogenic chemicals are left
unchanged but the toxic elements are inactivated. By feeding mushrooms to the
reindeer and then collecting and drinking the reindeer urine, our early Santa
found a simple chemical detoxification process. If this sounds gross, recall
how Premarin is made.
If you are into trivia,
some scholars think that the origin of the phrase "to get pissed,"
was started by this urine-drinking; it preceded the consumption of alcohol by
thousands of years and left the consumer incredibly plastered.
Does the image of an
ancient shaman dressed in his traditional red fur hat trimmed with fur and long
black leather boots coming back from collecting mushrooms carrying large sacks
of bright red ‘gifts' sound a bit like the fellow in Coca-cola ads?
The hallucinogenic
effect of the amanita mushroom often includes the feeling of flying, which
probably accounts for the image of bell decked reindeer flying around the North
Pole with a hallucinating shaman laughing in his sled.
While pondering that
ancient Santa stumbling stoned on reindeer piss and falling through the smoke
hole of his yurt, come back to the subject of betulinic acid which is what this
article is really about.
Birch Trees and
Betulinic Acid:
Betulinic acid is found
in birch tree bark. These trees inhabit the northern cold latitudes and were
very familiar to the reindeer peoples of northern Europe and Asia . Over the
last few years a growing body of published scientific research has made this
chemical appear very interesting for its potential effect in cancer treatment.
Although birch bark has
a long history of use in making various herbal medicines, modern interest
didn't start until ten years ago. In March, 1995, John Pezzuto of the
University of Illinois , Chicago reported that a compound isolated from birch
bark called betulinic acid, was able to kill human melanoma cells transplanted
into mice.
Dr. Pezzuto extracted
betulin from birch logs found in an old woodpile near his Chicago laboratory
and converted this into betulinic acid (BA). Unlike conventional chemotherapy,
this compound caused no apparent side effects and, for obvious reasons, is
potentially very inexpensive. This initial research spurred a flurry of studies
confirming the initial findings, delineating the chemical mechanisms of action,
or at least some of them, and finding BA effective at killing other types of
cancer cell besides melanoma.
Studies published in
the last few years continue to confirm betulinic acid (BA) kills melanoma
cells. Eight years after the original article from 1995 [i] the original research group published again, providing
greater detail to the mechanism of action. [ii] Various chemical
derivatives of BA have been created and examined with even greater
cytotoxicity, 2005. [iii] [iv] [v] [vi]While toxic to skin
cancer cells BA encourages cell differentiation in normal skin cells according
to a 2005 study. [vii]
Betulinic acid may be useful in treating
other cancers besides melanoma. Research has been published suggesting use of
BA in treatment of leukemia, [viii] [ix] lung, [x] head
and neck cancer, [xi] and
brain [xii] cancer.
It enhances the effect of other treatments, including vitamin D on leukemia, [xiii]vincristine
on lung cancer, [xiv] hyperthermia [xv] and
potentiates other anticancer drugs. [xvi]
Doctrine of Signatures and Chaga
Mushroom:
There is an old theory in herbal
medicine called the Doctrine of Signatures which suggests that the therapeutic
use of a plant can be inferred from the image, shape or form the plant
presents. In simpler word, the plant's appearance contains a message which
suggests the organ or illness it is useful to treat. It is interesting that the
skin of the birch tree yields a chemical useful in treating skin ailments. It
is even more interesting if you look at the appearance of a fungus that
occasionally grows on birch trees. This fungus, a mushroom polyspore called
Chaga, Innonotus obliquus , which parasitizes birch trees and can only be
described as looking like a tumor. The Chaga mushroom has been revered by those
same reindeer cultures that brought us Santa, and used as a medicine to treat
among other things, skin cancers. Although the mushroom can grow on other
trees, including alder and beech, only the mushrooms from birch trees are
reputed to have medicinal value.
Unlike most mushrooms, chaga is a
polypore, a fungus with pores instead of gills. Chaga is a parasite and draws
its nutrients out of living trees, rather than from the ground. Fungi digest
food outside their bodies by releasing enzymes into the surrounding
environment, breaking down organic matter into a form the fungus can then
absorb. Chaga absorb large amounts of betulinic acid from the birch trees and
convert it into various forms that can be ingested orally.
Chaga mushrooms are not easy to come
by. They often grow high in the trees at a height of 10 to 30 feet, which makes
collecting difficult. The Russians, the main commercial source of these
mushrooms, go out with ropes and harnesses. The ideal chaga fruiting body is 25
years old and may weigh 10 pounds. According to one chaga website, only one
birch tree in 15,000 yields a mushroom.
There is less research on Chaga than
on betulinic acid yet what there is looks promising. Chaga is
immunostimulating, having effects similar to other medicinal mushrooms. [xvii] It
has anti-inflammatory and pain relieving action. [xviii] It
acts as an antioxidant, [xix] preventing
damage to cell DNA. [xx]
What does this have to do with Santa
and his reindeer? Not much. Reindeer convert one medicinal plant substance into
another more ‘beneficial' for people. This sort of transformation by an
intermediary organism into something more useful to people is not unique. The
fermentation of sugars by yeast to make alcohol is the most obvious example.
The biotransformation of birch bark by Chaga mushrooms may yield a unique ally
in the treatment of specific illnesses. Betulinic acid appears useful on its
own yet we already know that certain chemical derivatives are even more
powerful. Chaga may provide a source of betulinic acid at once both more
bioavailable and useful. These mushrooms may provide benefits, in ways more
complex and more elegant than the research scientists have yet to figure out?
If nothing else the digression about Santa should provide food for thought this
holiday season.
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Note: In 1994 local Denver artist,
Tom Stimson traveled extensively documenting the shamanic use of Amanita
mushrooms in far eastern Russia . He produced and sells a fascinating video on
these Siberian shamans who still employ amanita mushrroms. http://pageformer.com/mukomor/
References
Discovery of betulinic acid as a selective inhibitor of human
melanoma that functions by induction of apoptosis
Emily Pisha1, Heebyung Chai1, Ik-Soo Lee1, Tangai E. Chagwedera2,
Norman R. Farnsworth1, Geoffrey A. Cordell1, Christopher W.W. Beecher1, Harry H.S.
Fong1, A. Douglas Kinghorn1, Daniel M. Brown3, 5, Mansukh C. Wani3, Monroe E.
Wall3, Tina J. Hieken4, Tapas K. Das Gupta4 & John M. Pezzuto1, 4, 6
As a result of bioassay-guided fractionation, betulinic acid, a
pentacyclic triterpene, was identified as a melanoma-specific cytotoxic agent.
In follow-up studies conducted with athymic mice carrying human melanomas,
tumour growth was completely inhibited without toxicity. As judged by a variety
of cellular responses, antitumour activity was mediated by the induction of
apoptosis. Betulinic acid is inexpensive and available in abundant supply from
common natural sources, notably the bark of white birch trees. The compound is
currently undergoing preciinicai development for the treatment or prevention of
malignant melanoma.
Clin
Cancer Res. 2003
Jul;9(7):2866-75.
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Betulinic acid-induced programmed cell death in human melanoma cells involves mitogen-activated protein kinase activation.
Tan Y , Yu R , Pezzuto JM .
Program for Collaborative Research in the Pharmaceutical Sciences, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
Betulinic acid, a naturally occurring triterpene found in the bark of the white birch tree, has been demonstrated to induce programmed cell death with melanoma and certain neuroectodermal tumor cells. We demonstrate currently that treatment of cultured UISO-Mel-1 (human melanoma cells) with betulinic acid leads to the activation of p38 and stress activated protein kinase/c-Jun NH(2)-terminal kinase [widely accepted proapoptotic mitogen-activated protein kinases (MAPKs)] with no change in the phosphorylation of extracellular signal-regulated kinases (antiapoptotic MAPK). Moreover, these results support a link between the MAPKs and reactive oxygen species (ROS). As demonstrated previously, cells treated with betulinic acid generate ROS. Preincubation of cells with antioxidants blocks the process of programmed cell death, and prevents the phosphorylation of p38 and stress activated protein kinase/c-Jun NH(2)-terminal kinase. These data suggest that ROS act upstream of the MAPKs in the signaling pathway of betulinic acid. In addition to mediating these responses, treatment of cells with betulinic acid resulted in a gradual depolarization of mitochondrial membrane potential, a phenomenon established to contribute to the induction of programmed cell death. Interestingly, p38 was capable of partially modulating this perturbation, and investigations of mitochondria-associated apoptotic events indicate no involvement of known caspases. These data provide additional insight in regard to the mechanism by which betulinic acid induces programmed cell death in cultured human melanoma cells, and it likely that similar responses contribute to the antitumor effect mediated with human melanoma carried in athymic mice.
PMID: 12855667 [PubMed - indexed for MEDLINE]
Bioorg Med Chem. 2005
May 16;13(10):3447-54.
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Synthesis of phthalates of betulinic acid and betulin with cytotoxic activity.
Kvasnica M , Sarek J , Klinotova E , Dzubak P , Hajduch M .
Department of Organic and Nuclear Chemistry, Faculty of Science, Charles University in Prague , Hlavova 8, 128 43 Prague 2, Czech Republic .
Synthesis of 3beta-O-phthalic esters from betulinic acid and its esters and synthesis of phthalic esters from betulin and its monoacetates using classical acylation procedure with phthalic anhydride. The evaluation of cytotoxicity of the prepared compounds was using numbers of tumor cell lines in MTT test. It was discovered that hemiphthalic esters had better cytotoxicity than starting compounds as betulinic acid or quite inactive betulin.
PMID: 15848757 [PubMed - indexed for MEDLINE]
Bioorg
Khim. 2005
May-Jun;31(3):320-5.
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[Synthesis and antitumor activity of cyclopropane derivatives of betulinic and betulonic acids]
[Article in Russian]
Symon AV , Veselova NN , Kaplun AP , Vlasenkova NK , Fedorova GA , Liutik AI , Gerasimova GK , Shvrts VI .
New cyclopropane derivatives of betulin were synthesized by attachment of dichlorocarbenes or dibromocarbenes to the double bond of betulin diacetate, followed by the deprotection of hydroxyl groups. The betulin cyclopropane derivative was obtained from 20,29-dihydro-20,29-dichloromethylenebetulin by treatment with lithium in tert-butanol. These compounds were converted into the corresponding derivatives of betulonic acid by oxidation with chromium trioxide. The reduction of oxo group with sodium borohydride led to the corresponding derivatives of betulinic acid. 20,29-Dihydro-20,29-dichloromethylenebetulinic acid proved to be the most cytotoxic toward human melanoma of the Colo 38 and Bro lines and human ovarian carcinoma of the CaOv line (IC50 10 microM). 20,29-Dihydro-20,29-dibromomethylenebetulinic acid inhibited the growth of the Bro melanoma cell line and the CaOv carcinoma cell line practically by 50% at a concentration of 10 microM. The other derivatives of betulinic and betulonic acids were active toward all of the three cancer cell lines at concentrations higher than 10 microM. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 3; see also http://www.maik.ru.
PMID: 16004391 [PubMed - indexed for MEDLINE]
J Nat Prod. 2004 Jul;67(7):1100-5.
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Synthesis of A-seco derivatives of betulinic acid with cytotoxic activity.
Urban M , Sarek J , Klinot J , Korinkova G , Hajduch M .
Department of Organic and Nuclear Chemistry, Faculty of Science, Charles University in Prague , Hlavova 8, 128 43 Prague 2, Czech Republic .
In this study, the relationships between the chemical structure and cytotoxic activity of betulinic acid (1) derivatives were investigated. Eight lupane derivatives (1-8), one of them new (6), five diosphenols (9-13), four of them new (10-13), two new norderivatives (14 and 15), five seco derivatives (16-20), four of them new (16, 17, 19, and 20), and three new seco-anhydrides (21-23) were synthesized from 1, and their activities were compared with the activities of known compounds. The effects of substitution on the A-ring and esterification of the carboxyl group in position 28 on cytotoxicity were of special interest. Significant cytotoxic activity against the T-lymphoblastic leukemia cell line CEM was found in diosphenols 9 and 13 (TCS(50) 4 and 5 micromol/L) and seco-anhydrides 22 and 23 (TCS(50) 7 and 6 micromol/L). All compounds were also tested on cancer cell lines HT 29, K562, K562 Tax, and PC-3, and these confirmed activity of diosphenols 9, 10, and 11 and anhydride 22. Diosphenols, as the most promising group of derivatives, were further tested on four more lines (A 549, DU 145, MCF 7, SK-Mel2).
PMID: 15270560 [PubMed - indexed for MEDLINE]
Eur
J Pharmacol. 2004 Sep
13;498(1-3):71-8.
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Apoptotic activity of betulinic acid derivatives on murine melanoma B16 cell line.
Liu WK , Ho JC , Cheung FW , Liu BP , Ye WC , Che CT .
Department of Anatomy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China. ken-liu@cuhk.edu.hk
The mitochondrion plays a crucial role in the process of apoptosis and has thus become one of the targets for the search for potential chemotherapeutic agents. Betulinic acid [3beta-hydroxy-lup-20(19)lupaen-28-carbonic acid], a lupane-type triterpene which is abundant in many plant species, has been shown to exert a direct effect on the mitochondria and subsequent apoptosis in melanoma cells. Chemical synthesis and modification of betulinic acid are being explored to develop more potent derivatives. We present here the apoptotic activity of several natural derivatives of betulinic acid which were isolated from the roots of a Chinese medicinal herb, Pulsatilla chinensis (Bge) Regel [Ye, W., Ji, N.N., Zhao, S.X., Liu, J.H., Ye, T., McKervey, M.A., Stevenson, P., 1996. Triterpenoids from Pulsatilla chinensis. Phytochemistry 42, 799-802]. Of the five compounds tested, 3-oxo-23-hydroxybetulinic acid was the most cytotoxic on murine melanoma B16 cells (IC50=22.5 microg/ml), followed by 23-hydroxybetulinic acid and betulinic acid (IC50=32 and 76 microg/ml, respectively), with lupeol and betulin exhibiting the weakest cytotoxicity (IC50> or =100 microg/ml). Exposure of B16 cells to betulinic acid, 23-hydroxybetulinic acid and 3-oxo-23-hydroxybetulinic acid caused a rapid increase in reactive oxidative species production and a concomitant dissipation of mitochondrial membrane potential in a dose- and time-dependent manner, which resulted in cell apoptosis, as demonstrated by fluorescence microscopy, gel electrophoresis and flow-cytometric analysis. Cell cycle analysis further demonstrated that both 3-oxo-23-hydroxybetulinic acid and 23-hydroxybetulinic acid dramatically increased DNA fragmentation at the expense of G1 cells at doses as low as 12.5 and 25 microg/ml, respectively, thereby showing their potent apoptotic properties. Our results showed that hydroxylation at the C3 position of betulinic acid is likely to enhance the apoptotic activity of betulinic acid derivatives (23-hydroxybetulinic acid and 3-oxo-23-hydroxybetulinic acid) on murine melanoma B16 cells.
PMID: 15363977 [PubMed - indexed for MEDLINE]
Exp Dermatol. 2005 Oct;14(10):736-43.
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Betulinic acid induces apoptosis in skin cancer cells and differentiation in normal human keratinocytes.
Faculty of Pharmacy, Institute of Pharmaceutical Biology and Pharmacology, Martin-Luther-University Halle-Wittenberg, Halle/Saale, Germany .
Betulinic acid (BA), a pentacyclic triterpene of plant origin, induces cell death in melanoma cells and other malignant cells of neuroectodermal origin. Little is known about additional biological effects in normal target cells. We show, in this study, that BA induces differentiation as well as cell death in normal human keratinocytes (NHK). Cytotoxicity profiles of BA are compared among normal human keratinocytes, HaCaT cells, IGR1 melanoma cells and normal melanocytes. As expected, BA is toxic to all cell types, normal and malignant, but varies in its cytotoxic potency and in the extent of induction of apoptotic vs. necrotic cell death in the four different skin cell types. Apoptosis is proved by annexin V and Apo2.7 binding and by DNA fragmentation. Induction of differentiation-associated antigens in keratinocytes--filaggrin and involucrin--is demonstrated, together with specific morphological changes in treated cell cultures. BA, apart from its cytotoxic activities in cellular systems, is capable of inducing differentiation of NHK into corneocytes without immediately provoking apoptotic cell death.
PMID: 16176281 [PubMed - indexed for MEDLINE]
Leukemia. 2004
Aug;18(8):1406-12.
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Betulinic acid-induced apoptosis in leukemia cells.
Department of Oncology/Hematology, Dr von Haunersches Kinderspital, Lindwurmstr 4, Munchen , Germany .
Betulinic acid (BA), a natural component isolated from Birch trees, effectively induces apoptosis in neuroectodermal and epithelial tumor cells and exerts little toxicity in animal trials. Here, we show that BA-induced marked apoptosis in 65% of primary pediatric acute leukemia cells and all leukemia cell lines tested. When compared for in vitro efficiency with conventionally used cytotoxic drugs, BA was more potent than nine out of 10 standard therapeutics and especially efficient in tumor relapse. No crossresistances were found between BA and any cytotoxic drug. Intracellular apoptosis signaling in leukemia tumor cells paralleled the pathway found in neuroectodermal cells involving caspases, but not death receptors. In isolated mitochondria, BA induced release of both cytochrome c and Smac. Taken together, BA potently induces apoptosis in leukemia cells and should be further evaluated as a future drug to treat leukemia
Toxicol Lett. 2005 Mar 15;155(3):343-51.
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Betulinic acid induces apoptosis in human chronic myelogenous leukemia (CML) cell line K-562 without altering the levels of Bcr-Abl.
Raghuvar Gopal DV , Narkar AA , Badrinath Y , Mishra KP , Joshi DS .
Laboratory Nuclear Medicine Section, Isotope Group, BARC, C/o Tata Memorial Hospital Annexe, Jerbai Wadia Road, Parel, Mumbai 400012, India.
Betulinic acid (BA), a plant derived triterpenoid, isolated from various sources shows cytotoxicity in cell lines of melanoma, neuroectodermal and malignant brain tumors. Chronic myelogenous leukemia (CML) is characterized by Philadelphia chromosome (Bcr-Abl), a molecular abnormality leading to the intrinsic tyrosine kinase activity that provides growth and survival advantage to the cells. Present study describes the cytotoxicity of BA on human CML cell line K-562, positive for Bcr-Abl. The decrease in the viability of K-562 cells treated with BA at different concentrations and time intervals was assessed using MTT assay. Cell death induced by BA was determined to be apoptotic as measured by FACS analysis of PI stained nuclei, PS externalization by Annexin-V fluorescence and characteristic DNA fragmentation. DiOC6(3) fluorescent probe determined alterations in the mitochondrial membrane potential (MMP). RT-PCR confirmed the expression levels of Bcr-Abl in controls and K-562 cells treated with BA. The rapid loss of MMP of K-562 cells upon treatment with BA shows the direct activation of apoptosis at the level of mitochondria, overcoming the resistance of the high levels of expression of Bcr-Abl.
PMID: 15649617 [PubMed - indexed for MEDLINE]
Br J Cancer. 2004 Apr 19;90(8):1672-8.
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Betulinic acid augments the inhibitory effects of vincristine on growth and lung metastasis of B16F10 melanoma cells in mice.
Sawada N , Kataoka K , Kondo K , Arimochi H , Fujino H , Takahashi Y , Miyoshi T , Kuwahara T , Monden Y , Ohnishi Y .
Department of Oncological and Regenerative Surgery, School of Medicine , The University of Tokushima , Tokushima 770-8503, Japan .
We examined the antitumour effect of a combination of betulinic acid (BA) and vincristine (VCR) on murine melanoma B16F10 cells in vitro and in vivo. Betulinic acid, a pentacyclic triterpene, showed a synergistic cytotoxic effect on melanoma cells by combinational use of VCR. Betulinic acid and VCR induced cell cycle arrest at different points (BA at G1 phase and VCR at G2/M phase) and caused apoptosis in B16F10 melanoma cells. In the in vivo study, VCR inhibited metastasis of tumour cells to the lung. The addition of BA to VCR augmented suppression of the experimental lung metastasis of melanoma cells in C57BL/6 mice. The number of lung nodules of more than 1 mm in diameter in mice treated with BA and VCR was less than that in mice treated with VCR alone. These results suggest that BA is an effective supplement for enhancing the chemotherapeutic effect on malignant melanoma.
PMID: 15083202 [PubMed - indexed for MEDLINE]
Head Neck. 2003 Sep;25(9):732-40.
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Betulinic acid: a new cytotoxic compound against malignant head and neck cancer cells.
Thurnher D , Turhani D , Pelzmann M , Wannemacher B , Knerer B , Formanek M , Wacheck V , Selzer E .
Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Vienna, Wahringer Gurtel 18-20, A-1090 Vienna, Austria. dietmar.thrunher@univie.ac.at
BACKGROUND: A new compound, betulinic acid, has been found to be cytotoxic against a variety of tumor cells originating from the neural crest. Its efficacy against head and neck squamous cellular carcinoma cell lines has so far not been tested. METHODS: Cell numbers were assayed by automated counting; caspase activation and programmed cell death were determined using an antibody specific for an apoptosis-associated epitope in epithelial cells. The expression pattern of Bcl-2 family members was assessed by Western blotting. RESULTS: In two HNSCC cell lines betulinic acid induced apoptosis, which was characterized by a dose-dependent reduction in cell numbers, emergence of apoptotic cells, and an increase in caspase activity. Western blot analysis of the expression of various Bcl-2 family members in betulinic acid-treated cells showed, surprisingly, a suppression of the expression of the proapoptotic protein Bax but no changes in Mcl-1 or Bcl-2 expression. CONCLUSION: These data clearly demonstrate for the first time that betulinic acid has apoptotic activity against HNSCC cells. Copyright 2003 Wiley Periodicals, Inc. Head Neck 25: 732-740, 2003
PMID: 12953308 [PubMed - indexed for MEDLINE]
Acta Neurochir (Wien). 2004 Jul;146(7):721-9. Epub 2004 May 21.
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Cell death induction by betulinic acid, ceramide and TRAIL in primary glioblastoma multiforme cells.
Dr. von Haunersches Kinderspital, Munich , Germany . I.Jeremias@lrz.uni-muenchen.de
BACKGROUND: Glioblastoma multiforme (WHO Grade IV, GBM) is the most malignant brain tumour with a mean survival time of less than one year. Betulinic acid, ceramide and TRAIL (TNF-related apoptosis inducing ligand) represent novel therapeutic agents for potential use in GBM. METHOD: Primary GBM cells of 21 patients with macroscopically complete tumour resection were tested in vitro for cell death induction by betulinic acid, ceramide, TRAIL and established therapeutics (BCNU, cisplatin, doxorubicin, vincristin and gamma-irradiation). FINDINGS: At peak plasma concentrations (PPC), Betulinic acid, ceramide and TRAIL induced cell death in primary GBM cells at higher rates than established cytotoxic drugs. Specific cell death > or =75% was observed in 43% (9/21), 38% (8/21), and 19% (4/21) for betulinic acid, ceramide, and TRAIL respectively, while this was only found in 5% (1/21) of gamma-irradiated and cisplatin-treated cells, and in none of the GBM cultures, where BCNU or vincristin were applied in PPC. CONCLUSION: Due to a markedly improved cell death of GBM cells as compared with established therapeutics, Betulinic acid, ceramide and TRAIL might represent potent substances for future treatment of GBM.
PMID: 15197616 [PubMed - indexed for MEDLINE]
[xiii] Betulinic
acid enhances 1a,25-dihydroxyvitamin D3-induced differentiation in human HL-60
promyelocytic leukemia cells
Ka-Hung
Poon, Jinxia Zhang, Cheng Wang, Anfernee Kai-Wing Tse, Chi-Keung Wan, Wang-Fun
Fong
Bioactive
Products Research Group
Published
at: Anti-cancer Drugs July 2004
Br J Cancer. 2004 Apr 19;90(8):1672-8.
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Betulinic acid augments the inhibitory effects of vincristine on growth and lung metastasis of B16F10 melanoma cells in mice.
Sawada N , Kataoka K , Kondo K , Arimochi H , Fujino H , Takahashi Y , Miyoshi T , Kuwahara T , Monden Y , Ohnishi Y .
Department of Oncological and Regenerative Surgery, School of Medicine , The University of Tokushima , Tokushima 770-8503, Japan .
We examined the antitumour effect of a combination of betulinic acid (BA) and vincristine (VCR) on murine melanoma B16F10 cells in vitro and in vivo. Betulinic acid, a pentacyclic triterpene, showed a synergistic cytotoxic effect on melanoma cells by combinational use of VCR. Betulinic acid and VCR induced cell cycle arrest at different points (BA at G1 phase and VCR at G2/M phase) and caused apoptosis in B16F10 melanoma cells. In the in vivo study, VCR inhibited metastasis of tumour cells to the lung. The addition of BA to VCR augmented suppression of the experimental lung metastasis of melanoma cells in C57BL/6 mice. The number of lung nodules of more than 1 mm in diameter in mice treated with BA and VCR was less than that in mice treated with VCR alone. These results suggest that BA is an effective supplement for enhancing the chemotherapeutic effect on malignant melanoma.
PMID: 15083202 [PubMed - indexed for MEDLINE]
Int J Hyperthermia. 2002 Mar-Apr;18(2):153-64.
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Betulinic acid sensitization of low pH adapted human melanoma cells to hyperthermia.
Wachsberger PR , Burd R , Wahl ML , Leeper DB .
Department of Radiation
Oncology, Kimmel Cancer Center and Thomas Jefferson University , Philadelphia , PA 19107 , USA . phyllis.wachsberger@mail.tju.edu
Betulinic acid is a known inducer of apoptosis in human melanoma that is most effective under conditions of low pH. It was hypothesized that betulinic acid, in combination with acute acidification and/or hyperthermia, would induce higher levels of apoptosis and cytotoxicity in low pH-adapted human melanoma cells than in cells grown at pH 7.3. DB-1 human melanoma cells, adapted to a tumour-like growth pH of 6.7, were exposed to hyperthermia (2h at 42 degrees C) and/or betulinic acid (4-10 microg/ml) and compared with cells grown at a physiological pH of 7.3 or after acute acidification from pH 7.3-6.3 or pH 6.7-6.3. Betulinic acid induced higher levels of apoptosis and cytotoxicity in low pH-adapted cells than in cells grown at pH 7.3, as measured by the terminal deoxynucleotidyl transferase (TdT) DNA fragmentation assay (TUNEL), the MTS cell viability assay, and single cell survival. Acute acidification of low pH adapted cells rendered them more susceptible to betulinic acid-induced apoptosis and cytotoxicity. In the presence of hyperthermia at 42 degrees C for 2 h, cells grown at pH 7.3 were not sensitized to heat killing by betulinic acid, whereas cells grown at pH 7.3 and acutely acidified to pH 6.3, cells adapted to growth at pH 6.7 and cells adapted to growth at pH 6.7 and acutely acidified to pH 6.3 were all similarly sensitized to heat killing by betulinic acid, with survival values of 5, 9 and 2%, respectively. It is concluded that betulinic acid may be useful in potentiating the therapeutic efficacy of hyperthermia as a cytotoxic agent in acidotic areas of tumours with minimal effect in normal tissues growing at pH 7.3.
Betulinic acid is a known inducer of apoptosis in human melanoma that is most effective under conditions of low pH. It was hypothesized that betulinic acid, in combination with acute acidification and/or hyperthermia, would induce higher levels of apoptosis and cytotoxicity in low pH-adapted human melanoma cells than in cells grown at pH 7.3. DB-1 human melanoma cells, adapted to a tumour-like growth pH of 6.7, were exposed to hyperthermia (2h at 42 degrees C) and/or betulinic acid (4-10 microg/ml) and compared with cells grown at a physiological pH of 7.3 or after acute acidification from pH 7.3-6.3 or pH 6.7-6.3. Betulinic acid induced higher levels of apoptosis and cytotoxicity in low pH-adapted cells than in cells grown at pH 7.3, as measured by the terminal deoxynucleotidyl transferase (TdT) DNA fragmentation assay (TUNEL), the MTS cell viability assay, and single cell survival. Acute acidification of low pH adapted cells rendered them more susceptible to betulinic acid-induced apoptosis and cytotoxicity. In the presence of hyperthermia at 42 degrees C for 2 h, cells grown at pH 7.3 were not sensitized to heat killing by betulinic acid, whereas cells grown at pH 7.3 and acutely acidified to pH 6.3, cells adapted to growth at pH 6.7 and cells adapted to growth at pH 6.7 and acutely acidified to pH 6.3 were all similarly sensitized to heat killing by betulinic acid, with survival values of 5, 9 and 2%, respectively. It is concluded that betulinic acid may be useful in potentiating the therapeutic efficacy of hyperthermia as a cytotoxic agent in acidotic areas of tumours with minimal effect in normal tissues growing at pH 7.3.
Neoplasia. 2005 Feb;7(2):162-70.
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University Children's Hospital, Prittwitzstrasse 43, Ulm 89075 , Germany .
simone.fulda@medizin.uni-ulm.de
We previously described that betulinic acid (BetA), a naturally occurring pentacyclic triterpenoid, induces apoptosis in tumor cells through the mitochondrial pathway. Here, for the first time, we provide evidence that BetA cooperated with anticancer drugs to induce apoptosis and to inhibit clonogenic survival of tumor cells. Combined treatment with BetA and anticancer drugs acted in concert to induce loss of mitochondrial membrane potential and the release of cytochrome c and Smac from mitochondria, resulting in activation of caspases and apoptosis. Overexpression of Bcl-2, which blocked mitochondrial perturbations, also inhibited the cooperative effect of BetA and anticancer drugs, indicating that cooperative interaction involved the mitochondrial pathway. Notably, cooperation of BetA and anticancer drugs was found for various cytotoxic compounds with different modes of action (e.g., doxorubicin, cisplatin, Taxol, VP16, or actino-mycin D). Importantly, BetA and anticancer drugs cooperated to induce apoptosis in different tumor cell lines, including p53 mutant cells, and also in primary tumor cells, but not in human fibroblasts indicating some tumor specificity. These findings indicate that using BetA as sensitizer in chemotherapy-based combination regimens may be a novel strategy to enhance the efficacy of anticancer therapy, which warrants further investigation.
We previously described that betulinic acid (BetA), a naturally occurring pentacyclic triterpenoid, induces apoptosis in tumor cells through the mitochondrial pathway. Here, for the first time, we provide evidence that BetA cooperated with anticancer drugs to induce apoptosis and to inhibit clonogenic survival of tumor cells. Combined treatment with BetA and anticancer drugs acted in concert to induce loss of mitochondrial membrane potential and the release of cytochrome c and Smac from mitochondria, resulting in activation of caspases and apoptosis. Overexpression of Bcl-2, which blocked mitochondrial perturbations, also inhibited the cooperative effect of BetA and anticancer drugs, indicating that cooperative interaction involved the mitochondrial pathway. Notably, cooperation of BetA and anticancer drugs was found for various cytotoxic compounds with different modes of action (e.g., doxorubicin, cisplatin, Taxol, VP16, or actino-mycin D). Importantly, BetA and anticancer drugs cooperated to induce apoptosis in different tumor cell lines, including p53 mutant cells, and also in primary tumor cells, but not in human fibroblasts indicating some tumor specificity. These findings indicate that using BetA as sensitizer in chemotherapy-based combination regimens may be a novel strategy to enhance the efficacy of anticancer therapy, which warrants further investigation.
PMID: 15802021 [PubMed - indexed for MEDLINE]
Immuno-stimulating
effect of the endo-polysaccharide produced by submerged culture of Inonotus
obliquus.
Life Sci.
2005 Sep 23;77(19):2438-56.
PMID:
15970296 [PubMed - indexed for MEDLINE]
In vivo
and in vitro anti-inflammatory and anti-nociceptive effects of the methanol
extract of Inonotus obliquus.
J
Ethnopharmacol. 2005 Oct 3;101(1-3):120-8.
PMID:
15905055 [PubMed - in process]
J Ethnopharmacol.
2005 Jan 4;96(1-2):79-85.
PMID:
15588653 [PubMed - indexed for MEDLINE]
Chaga
mushroom extract inhibits oxidative DNA damage in human lymphocytes as assessed
by comet assay.
Biofactors.
2004;21(1-4):109-12.
PMID:
15630179 [PubMed - indexed for MEDLINE]
[Treatment of actinic keratoses with birch bark extract: a
pilot study]
[Article in German]
Universitats-Hautklinik, Hauptstr. 7, D-79104 Freiburg .
BACKGROUND: Birch bark contains a variety of
apoptosis-inducing and anti-inflammatory substances such as betulinic acid,
betulin, oleanolic acid and lupeol. Therefore, birch bark extract may be
effective in the treatment of actinic keratoses. To address this issue, a pilot
study using a standardized birch bark ointment was performed. METHODS:
Twenty-eight patients with actinic keratoses were enrolled in this prospective,
non-randomized pilot study. Fourteen patients were treated with birch bark
ointment only; fourteen patients received a combination therapy with
cryotherapy and birch bark ointment. Treatment response was assessed clinically
after two months. RESULTS: Clearing of more than 75 % of the lesions was seen
in 79 % of the patients treated with birch bark ointment monotherapy. The
response rate of the combined treatment modality was 93 %. Therapy with birch
bark ointment was well tolerated. CONCLUSION: In this pilot study, a
standardized birch bark extract was effective in the treatment of actinic
keratoses. This therapy is easy to perform and it has no side effects. Birch
bark ointment may be a new therapeutic option for actinic keratoses.
PMID: 16503940 [PubMed - indexed for MEDLINE
Betulinic acid
derivatives as anticancer agents: structure activity relationship.
Medicinal Chemistry, Dabur
Research Foundation, 22 Site IV, Sahibabad, Ghaziabad 201010, UP, India .
Betulinic acid, a
pentacyclic triterpene, is widely distributed throughout the tropics. It
possesses several biological properties such as anticancer, anti-inflammatory,
antiviral, antiseptic, antimalarial, spermicidal, antimicrobial,
antileshmanial, antihelmentic and antifeedent activities. However, betulinic
acid was highly regarded for its anticancer and anti-HIV activities. Anticancer
role of betulinic acid appeared by inducing apoptosis in cells irrespective of
their p53 status. Due to high order safety in betulinic acid, a number of
structural modifications carried out to improve its potency and efficacy. The
C-1, C-2, C-3, C-4, C-20 and C-28 positions are the diversity centers in
betulinic acid, and the derivatives resulted on various structural modifications
at these positions screened for their anticancer activity. This review presents
the structure activity relationship carried out on C-1, C-2, C-3, C-4, C-20,
C-28, A-ring, D-ring and E-ring modified betulinic acid derivatives. We have
compiled the most active betulinic acid derivatives along with their activity
profile in each series. Structure activity relationship studies revealed that
C-28 carboxylic acid was essential for the cytotoxicity. The halo substituent
at C-2 position in betulinic acid enhanced the cytotoxicity. Though the
relation of the cytotoxicity with the nature of substituents at C-3 position
could not be generalized but the ester functionality appeared to be a better
substituent for enhancing the cytotoxicity. An interesting observation is that
the three rings skeleton (A, B and C rings) had played an important role in
eliciting anticancer activity, which could be a new molecular skeleton to
design new anticancer drugs.
PMID: 16712455 [PubMed -
indexed for MEDLINE]
[iii] Honda
T, Liby KT, Su X, Sundararajan C, Honda Y, Suh N, Risingsong R, Williams CR,
Royce DB, Sporn MB, Gribble GW. Related
Articles, Links Design, synthesis, and anti-inflammatory
activity both in vitro and in vivo of new betulinic acid analogues having an
enone functionality in ring A.
Bioorg Med Chem Lett. 2006 Dec 15;16(24):6306-9. Epub 2006 Sep 25.
PMID: 16996735 [PubMed - in process]
Bioorg Med Chem Lett. 2006 Dec 15;16(24):6306-9. Epub 2006 Sep 25.
PMID: 16996735 [PubMed - in process]
Broad in vitro
efficacy of plant-derived betulinic acid against cell lines derived from the
most prevalent human cancer types.
Laboratory for
Experimental Oncology and Radiobiology (LEXOR), Center for Experimental and
Molecular Medicine, Academic Medical Center (AMC), Meibergdreef 9, 1105 AZ
Amsterdam , The Netherlands .
Betulinic acid (BA) is a
widely available plant-derived triterpene with reported activity against cancer
cells of neuroectodermal origin and leukaemias . Treatment with BA was shown
to protect mice against transplanted human melanoma and led to tumor
regression. In contrast, cells from healthy tissues were resistant to BA and
toxic side-effects in animals were absent. These findings have raised
interest in the chemotherapeutical anti-cancer potential of BA. A comprehensive
assessment of the efficacy of BA against the clinically most important cancer
types is currently lacking. Therefore, we tested
the in vitro sensitivity of broad cell line panels derived from lung,
colorectal, breast, prostate and cervical cancer, which are the prevalent cancer
types characterized with highest mortalities in woman and men. Multiple assays were used in
order to allow a reliable assessment of anti-cancer efficacy of BA. After 48h
of treatment with BA, cell viability as assessed with MTT and cell death as
measured with propidium iodide exclusion showed clear differences in
sensitivity between cell lines. However, in all cell lines tested colony
formation was completely halted at remarkably equal BA concentrations that are
likely attainable in vivo. Our
results substantiate the possible application of BA as a chemotherapeutic agent
for the most prevalent human cancer types.
PMID: 17169485 [PubMed -
as supplied by publisher]
Betulinic acid, a natural cytotoxic agent, fails to trigger
apoptosis in human Burkitt's lymphoma-derived B-cell lines.
Childhood Cancer Research Unit, Department of Woman and
Child Health, Karolinska University Hospital , Stockholm , Sweden .
Betulinic acid (BA), a pentacyclic triterpene of natural
origin, effectively induces apoptosis in neuroectodermal tumors and was
recently shown to be a potent trigger of cell death in human leukemia-derived
cell lines. To
explore the potential of BA in the treatment of hematologic malignancies, we
tested a panel of 10 Burkitt's lymphoma (BL)-derived B-cell lines for
sensitivity to BA. The human Jurkat T leukemia cell line was included as a
positive control. Our
studies show that BA exerts cytotoxic effects in some of the BL cell lines
tested, including DG75, a chemoresistant BL cell line. However, cell death was
caspase-independent, as evidenced by a lack of protection by zVAD-fmk, a
pancaspase inhibitor, and displayed signs of necrosis. Furthermore, BA-induced caspase
activation was seen to a minor extent in only 1 of the 10 BL cell lines tested
(Ramos, a p53-deficient cell line), but was readily detected in Jurkat cells. Together, these studies
indicate that resistance to BA-induced apoptosis is a common feature of BL-derived
cell lines. Copyright 2005 Wiley-Liss, Inc.
PMID: 16003746 [PubMed - indexed for MEDLINE]
Pharmacological
properties of the ubiquitous natural product betulin.
Faculty of
Pharmacy, Division of Pharmaceutical Chemistry, University of Helsinki , Helsinki
, Finland .
Betulin
(lup-20(29)-ene-3beta,28-diol) is an abundant naturally occurring triterpene
and it is found predominantly in bushes and trees forming the principal
extractive (up to 30% of
dry weight) of the bark of birch trees . Presently, there is no
significant use for this easily isolable compound, which makes it a potentially
important raw material for polymers and a precursor of biologically active
compounds. Betulin can be
easily converted to betulinic acid, which possesses a wide spectrum of
biological and pharmacological activities. Betulinic acid has antimalarial and
anti-inflammatory activities. Betulinic acid and its derivatives have
especially shown anti-HIV activity and cytotoxicity against a variety of tumor
cell lines comparable to some clinically used drugs . A new mechanism of action has
been confirmed for some of the most promising anti-HIV derivatives, which makes
them potentially useful additives to the current anti-HIV therapy. Betulinic acid is specifically
cytotoxic to several tumor cell lines by inducing apoptosis in cells. Moreover,
it is non-toxic up to 500 mg/kg body weight in mice. The literature concerning
derivatization of betulin for structure-activity relationship (SAR) studies and
its pharmacological properties is reviewed.
PMID:
16716572 [PubMed - indexed for MEDLINE]
Combination of betulinic acid with cisplatin--different
cytotoxic effects in two head and neck cancer cell lines.
Department of Otorhinolaryngology, Head and
Neck Surgery, Medical University of Vienna, Waehringer Guertel 18-20, A-1090
Vienna, Austria.
Betulinic acid (BetA), a new experimental
cytotoxic compound that is active against human melanoma cells and
neuroectodermal tumor cells, has recently been shown to be also effective
against head and neck squamous carcinoma cells (HNSCC). In this study we
investigated BetA in combination with cisplatin in squamous cell carcinoma cell
lines of the tongue. SCC25 and SCC9 were treated with BetA and/or cisplatin.
Cells were counted with an automated analyzing system. Caspase activation was
determined using the M30 Cyto-Death ELISA, expression of the anti-apoptotic
protein Mcl-1 by Western blot analysis. Visualization of apoptotic cells was
achieved by immunohistochemistry. Synergistic cytotoxic effect and the
induction of apoptosis under combined treatment was observed in SCC25 cells
only after 24 or 48 h, whereas treatment of SCC25 cells for 72 h with BetA and
cisplatin showed antagonism or subadditive effects. In SCC9 cells, antagonism
occurred over an increase of dose and time during treatment. Furthermore, we
could not demonstrate a significant alteration in the expression of the
anti-apoptotic protein, Mcl-1. Our in vitro data demonstrate that BetA seems to
be an unlikely candidate for combination with cisplatin in the treatment of
head and neck cancer.
PMID: 16077972 [PubMed - indexed for MEDLINE]
Physical, Chemical
and Pharmacological Characterization of a New Oleogel-Forming Triterpene
Extract from the Outer Bark of Birch (Betulae Cortex).
Carl
Gustav Carus-Institut, Niefern-Oschelbronn , Germany .
Triterpenes
are biologically active secondary plant substances that display antimicrobial,
hepatoprotective and anti-inflammatory effects. However, the poor solubility of
triterpenes in both polar and non-polar solvents as well as expensive
purification procedures have prevented the large-scale isolation of these
compounds for medicinal purposes. Here, we describe a novel quantitative
extraction method of triterpenes from the outer bark of birch ( BETULA species)
in which betulin, a lupan triterpene, predominates. The resulting highly
purified triterpene extract (TE) in the form of a dry powder contains betulin
as the major compound, but also betulinic acid, lupeol, erythrodiol and
oleanolic acid. We have found that this TE is able to form an oleogel, thus
providing an opportunity for the topical application of pharmacologically
relevant amounts of triterpenes. Furthermore, we have investigated the TE in
comparison to its major isolated compounds in cell culture experiments with
human immortalized keratinocytes and skin cancer cells. We could demonstrate
dose-dependent cytotoxic and apoptosis-inducing effects of TE and betulin.
These experimental data support the notion from a previous clinical study that TE
from the outer bark of birch might represent a new tool for the topical
treatment of skin cancer and skin cancer precursors like actinic keratoses.
PMID:
17091432 [PubMed - as supplied by publisher]
January 31, 2006
NATURNORTH TECHNOLOGIES
BUILDING BIRCH BARK PROCESSING FACILITY NEAR DULUTH
Duluth, MN-NaturNorth Technologies
LLC (NaturNorth) has begun construction of a commercial production facility-the
first of its kind- in Two Harbors, about 20 miles north of Duluth. The facility
will concentrate the bark of the white paper birch tree (betula papyrifera)
into material that will be further processed into large quantities of
bioactive, low-toxicity compounds, like betulin and betulinic acid, potentially
useful in antifungals, antibacterials, and antivirals for use in
pharmaceuticals, cosmetics, crop protection and preservatives.
The Two Harbors facility is expected
to start operating in early April of 2006. It will be the first facility in the
world to process birch bark into material that can be efficiently converted
into commercial quantities of bioactive compounds. This also represents
NaturNorth's first effort to invest in capabilities to develop commercial
quantities of birch bark. “The Two Harbors bark processing facility represents
a strategic move to construct a significant production facility and a
demonstration site for our technology as well as lay the groundwork for further
expansion as commercial opportunities develop,” said David Peterson, President
and CEO of NaturNorth. “The new facility will initially employ five people,” he
said.
Peterson emphasized that NaturNorth
will be getting its supply of bark from existing forest products companies,
where birch bark is a by-product of their commercial operations. “Extracting
betulin from birch bark and producing betulinic acid for cosmetic and medicinal
purposes represent exciting potential uses for this otherwise wasted resource
from Minnesota 's forest products industry.”
NaturNorth's mission is to identify,
develop and produce natural, high-purity commercial compounds from birch bark and
their active derivatives. NaturNorth is able to supply commercial quantities of
previously unavailable bioactive natural products and their derivatives for use
in high-value applications.
NaturNorth is a public-private partnership between the
University of Minnesota Duluth, Potlatch Corporation (NYSE: PCH) and Synertec,
a subsidiary of ALLETE, Inc. (NYSE: ALE). Technologies to extract the betulin
were developed at UMD's Natural Resources Research Institute. “Together, these
partners have guided and supported NaturNorth and we are pleased to have the
opportunity to support this business in Minnesota ,” said L. Pendleton Siegel,
Chairman and CEO, Potlatch Corporation.
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