Archive for category Herbs
St. Johns Wort
Jul 12
Spirulina
Jul 11
Spirulina Platensis Benefits Against Herpes
Spirulina platensis has been shown to have antiviral activity, particularly against herpes virus.
J Nat Prod 1996 Jan;59(1):83-7 Calcium spirulan, an inhibitor of enveloped virus replication, from a blue-green alga Spirulina platensis. Hayashi T, Hayashi K, Maeda M, Kojima I. Faculty of Pharmaceutical Sciences and School of Medicine, Toyama Medical and Pharmaceutical University, Toyama, Japan. "Bioactivity-directed fractionation of a hot H2O extract from a blue-green alga Spirulina platensis led to the isolation of a novel sulfated polysaccharide named calcium spirulan (Ca-SP) as an antiviral principle. This polysaccharide was composed of rhamnose, ribose, mannose, fructose, galactose, xylose, glucose, glucuronic acid, galacturonic acid, sulfate, and calcium. Ca-SP was found to inhibit the replication of several enveloped viruses, including Herpes simplex virus type 1, human cytomegalovirus, measles virus, mumps virus, influenza A virus, and HIV-1. It was revealed that Ca-SP selectively inhibited the penetration of virus into host cells. Retention of molecular conformation by chelation of calcium ion with sulfate groups was suggested to be indispensable to its antiviral effect."
Zh Mikrobiol Epidemiol Immunobiol 2001 Mar-Apr;(2):114-8 Biological activity of Spirulina. Blinkova LP, Gorobets OB, Baturo AP; Mechnikov Research Institute for Vaccines and Sera, Moscow, Russia. "In this review information of Spirulina platensis (SP), a blue-green alga (photosynthesizing cyanobacterium) having diverse biological activity is presented. Due to high content of highly valuable proteins, indispensable amino acids, vitamins, beta-carotene and other pigments, mineral substances, indispensable fatty acids and polysaccharides, PS has been found suitable for use as bioactive additive. SP produces an immunostimulating effect by enhancing the resistance of humans, mammals, chickens and fish to infections, the capacity of influencing hemopoiesis, stimulating the production of antibodies and cytokines. Under the influence of SP macrophages, T and B cells are activated. SP sulfolipids have proved to be effective against HIV. Preparations obtained from SP biomass have also been found active against herpesvirus, cytomegalovirus, influenza virus, etc. SP extracts are capable in inhibiting cancerogenesis. SP preparations are regarded as functional products contributing to the preservation of the resident intestinal microflora, especially lactic acid bacilli and bifidobacteria, and to a decrease in the level of Candida albicans. The biological activity of SP with respect to microorganisms holds good promise for using these microalgae as components of culture media."
J Acquir Immune Defic Syndr Hum Retrovirol 1998 May 1;18(1):7-12 Inhibition of HIV-1 replication by an aqueous extract of Spirulina platensis (Arthrospira platensis). Ayehunie S, Belay A, Baba TW, Ruprecht RM. Laboratory of Viral Pathogenesis, Dana-Farber Cancer Institute, and Harvard Medical School, Boston, Massachusetts 02115, USA. "An aqueous extract of the blue-green filamentous algae Arthrospira platensis (previously called Spirulina platensis) inhibited HIV-1 replication in human T-cell lines, peripheral blood mononuclear cells (PBMC), and Langerhans cells (LC). Extract concentrations ranging between 0.3 and 1.2 microg/ml reduced viral production by approximately 50% (50% effective concentration [EC50]) in PBMCs. The 50% inhibitory concentration (IC50) of extract for PBMC growth ranged between 0.8 and 3.1 mg/ml. Depending on the cell type used, therapeutic indices ranged between 200 and 6000. The extract inactivated HIV-1 infectivity directly when preincubated with virus before addition to human T-cell lines. Fractionation of the extract revealed antiviral activity in the polysaccharide fraction and also in a fraction depleted of polysaccharides and tannins. We conclude that aqueous A platensis extracts contain antiretroviral activity that may be of potential clinical interest."
Rev Invest Clin
1996 Sep-Oct;48(5):389-99
Pharmacology and toxicology of Spirulina alga.
Chamorro G, Salazar M, Favila L, Bourges H. Toxicologia, Escuela Nacional de Ciencias Biologicas, Instituto Politecnico Nacional, Mexico, D.F. "Spirulina, a unicellular filamentous blue-green alga has been consumed by man since ancient times in Mexico and central Africa. It is currently grown in many countries by synthetic methods. Initially the interest in Spirulina was on its nutritive value: it was found almost equal to other plant proteins. More recently, some preclinical testing suggests it has several therapeutic properties such as hypocholesterolemic, immunological, antiviral and antimutagenic. This has led to more detailed evaluations such as nucleic acid content and presence of toxic metals, biogenic toxins and organic chemicals: they have shown absence or presence at tolerable levels according to the recommendations of international regulatory agencies. In animal experiments for acute, subchronic and chronic toxicity, reproduction, mutagenicity, and teratogenicity the algae did not cause body or organ toxicity. <<<More>>>
Spermicides
Jul 10
Saponins and Phytosterols
Saponins work as antioxidants by inhibiting the formation of free radicals. Saponins inhibit the human-immunodeficiency virus (HIV). Saponins bind CholesterolSaponins bind cholesterol in the gut. This includes both dietary cholesterol and cholesterol discharged by the liver in waste bile. By being bound, cholesterol is carried on for elimination with bowel movements rather than being resorbed by the body.
The Maasai Paradox
Scientists were once perplexed by the diet of the Maasai tribe in African. Maasai obtain 66 percent of calories from fat yet they do not suffer from hypercholesterolemia, atherosclerosis, gallbladder disease, or coronary heart disease. The paradox is that in western cultures high-fat diets have been positively correlated to these diseases. Typically, the high-fat Maasai foods are prepared as soups and routinely have 25 different herbs, usually roots and bark, added. Some of these herbs contain high levels of saponins which bind cholesterol.
Triterpenoid saponins
Copyright � 2003 Natural Health Resource Project
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The editors, like a librarian, cannot provide personal health counseling. This information is provided for educational reference purposes only. Please find qualified professional assistance if you need help making decisions about your health. |
Saponins natural tendency to ward off microbes makes them good candidates for treating fungal and yeast infections. These compounds serve as natural antibiotics, helping the body fight infections and microbial invasions.
These compounds appear to greatly enhance the effectiveness of certain vaccines, including ones for herpes simplex, HIV and influenza, when administered together with them. The compound functions as a helper agent, increasing the potency of the vaccines’ action.
Researchers are looking closely at saponins’ biochemical properties, which they believe include mechanisms that can stimulate the immune system, ward off microbial and fungal infections, protect against viruses.
Science News, Vol 148
Saponins can help humans fight fungal infections, combat microbes and viruses, boost the effectiveness of certain vaccine and knock out some kinds of tumor cells, particularly lung and blood cancers. They can also lower blood cholesterol thereby reducing heart disease. Their natural tendency to ward off microbes may prove to be especially useful for treating those difficult to control fungal and yeast infections.
Department of Human Nutrition
Kansas State University
Saponins have a direct stimulatory effect on the immune system.
Professor of Comparative Nutrition
Linus Pauling Institute, Oregon State University
There is strong evidence that some forms of arthritis may be caused or worsened by toxic substances in the intestines and these toxins may be absorbed by the body.
Saponins are not absorbed in the blood, but works within the small and large intestines.
Saponins act favorably on flora organisms of the intestines, encouraging growth of friendly bacteria and decreasing harmful bacteria.
GALENICA PHARMACEUTICALS ANNOUNCES RESEARCH AGREEMENT WITH THE UNIVERSITY OF ALABAMA AT BIRMINGHAM (UAB) TO EVALUATE HERPES SIMPLEX VIRUS VACCINE
- Studies Will Evaluate Effectiveness of a Recombinant Sub-unit Vaccine Against Herpes Virus Using Galenica’s Proprietary Immune Enhancer GPI-0100 -
BIRMINGHAM, <<<More>>>
Resveratrol
Jul 8
Resveratrol
A recent study presented at a meeting of the Interscience Conference on Anti-Microbial Agents reported that a chemical compound found in red wine might be effective in stopping HSV 1. This compound is known as resveratrol. Modified by a group of researchers at Northeastern Ohio University College of Medicine, resveratrol was found to stop infection in 99.9 percent of clinical trial participants. Interestingly, this same compound has also proven to be useful in helping prevent heart disease.
Prevention magazine reports in its April 2001 edition that studies are being conducted to develop an over-the-counter gel containing with the natural-occurring chemical resveratrol, which is found in grape skins and protects grapes from fungal infection.
Researchers have suspected for some time now this compound shows promise in containing outbreaks and shortening their duration.
John Docherty, Ph.D., a professor of microbiology and immunology at Northeastern Ohio Universities College of Medicine, has conducted a study on the effects of red wine on herpes simplex I (the virus that causes cold sores). He believes that higher concentrations of resveratrol than found in red wine were needed to effective against the virus. The amounts tested were 10 to 100 times than the amount found in a drop of red wine. (Prevention, April 2001, p.170-172)
In 1999, this same team discovered another compound from red wine called "resveratrol" blocked the reproduction of herpes cells. Since resveratrol wasn’t strong enough to make an effective drug, researchers began looking for chemical relatives that might prove to be more potent.
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Red Marine Algae
Jul 7
Quercetin
Jul 6
Quercetin
Quercetin
The first studies on Quercetin concentrated on its role in helping gout sufferers. (Murray) It appears to help by inhibiting xanthine oxidase ( which is what allopurinol does) and by preventing inflammation through the release of leukotrienes. It also affects some enzyme pathways.
Subsequently, Quercetin was found to have value for asthmatics (Whit/Asthma/8) because of its ability to inhibit the release of histamine, as well as leukotrienes.
Quercetin is a bioflavonoid found in grapes, grapefruit, onions, berries, green veggies, and legumesas well as Blue Green Algae. It has been the subject of dozens of recent scientific studies, because it appears to have the greatest activity of all the bioflavonoids. It inhibits the release of histamine by mast cells, thereby controlling the inflammation which is a part of such conditions as asthma, hay fever and asthma. Very recent research is finding it also of great value in the fight against prostate cancer, possibly because of its ability to inhibit inflammation. The study was so impressive that the prestigious journal Urology published it as a matter of "high priority". (1999;54:960-3) What the study found is that out of a group of 30 placebo controlled, double-blinded category 111 chronic prostatitis sufferers, those taking the Quercetin experienced improvement on the average of 40%, compared to 6% for placebo. The symptoms for which improvement was reported were: pain, voiding dysfunction, and quality of life. A second similar study reported 82% of the Quercetin users reported 25% or more improvement in their problems.
Along those lines, I would speculate it will also turn out to be a valuable protective substance against heart disease since inflammation is increasingly cited as a villain there. Quercetin is also valuable for its protective effect on small blood vessels.
Dr. Lise Anschuler, who teaches at Bastyr University, is very impressed both with Quercetin and the herb Ashwaganda. Her list of Quercetin�s manifold benefits is impressive!
Supports the health of tissue, and stabilizes connective tissue.
Inhibits the reactions of Mast cells, controlling inflammation
In vitro, it has proved to be anti-viral, anti-tumor, and anti-cancer
It modulates the endocrine system, reducing reaction to stress.
As an antioxidant it spares Vitamin C.
It inhibits angiogenesis, the formation of new blood vessels.
It decreases mutagenic effects
It induces apoptosis, which is programmed cell death.
Perhaps most important, it protects against eye problems. It inhibits the conversion of sugar to sorbitol. The eye cannot rid itself or sorbitol, and she states this is the main cause of neuropathy, cataracts and glaucoma.
Has a protective effect against the herpes virus, and the polio virus.
Prevents inflammation of the gastric and respiratory tracts.
Quercetin is also found in the valuable food Green Tea, and I want to draw your attention to the wonderful new source of that nutrient I have found, where each 30 drop dose of Chi Green Tea is equivalent to 10 cups of standard green tea. See under Resources (right) to order or for more information.
Quercetin as a supplement can be a little difficult to absorb, and many professionals recommend taking it with Bromelain to enhance its availability. There is a plus to this, as a study already done years ago ( EENT Monthly 46: 361-365 1967) documents the fact that people taking bromelain experienced extremely good results clearing up sinusitis!
| Quercetin
Monograph
Quercetin
Description Quercetin is widely distributed in the plant kingdom and is the most abundant of the flavonoid molecules. It is found in many often-consumed foods, including apple, onion, tea, berries, and brassica vegetables, as well as many seeds, nuts, flowers, barks, and leaves. It is also found in medicinal botanicals, including Ginkgo biloba, Hypericum perforatum (St. John’s Wort), Sambucus canadensis (Elder), and many others. It is often a major component of the medicinal activity of the plant, and has been shown in experimental studies to have numerous effects on the body. All flavonoids have the same basic chemical structure, a three-ringed molecule with hydroxyl (OH) groups attached (see Figure). A multitude of other substitutions can occur, giving rise to the many types of flavonoids. Flavonoids often occur in foods as a glycoside, meaning they have a sugar molecule (rhamnose, glucose, galactose, etc.) attached to the center (C) ring. Quercetin is the aglycone (meaning minus the sugar molecule) of a number of other flavonoids, including rutin, quercetrin, isoquercetin, and hyperoside. These molecules have the same structure as <<<More>>> |
Ponicidin
Jul 5
Ponicidin
Information on Ponicidin:
The herpes simplex virus thymidine kinase (HSV-TK)/ganciclovir (GCV) administration system is commonly used in gene therapy trials. We have evaluated the effect of ponicidin, a diterpenoid isolated from a plant, Rabdosia ternifolia, on the cell-killing activity of the anti-herpes drugs acyclovir (ACV) and GCV. Ponicidin preferentially activated HSV-1-specific TK but not cellular kinases. In HSV-infected cells, ponicidin significantly accumulated the phosphorylated metabolites of GCV and suppressed the extracellular release of GCV. These data suggested that the cytotoxicities of ACV and GCV in HSV-TK-expressing cells might be potentiated by ponicidin. After transfected with the HSV-1 TK gene, COS-1 and several human cancer cells became highly sensitive to the cytotoxic properties of the nucleoside analogs. When ponicidin at the concentration without antiviral activities (0.2 microg/mL) was combined with ACV or GCV, the cytotoxic levels in HSV-TK-expressing cells were enhanced by 3- to 87-fold and 5- to 52-fold, respectively, compared with the nucleoside alone. When the stability of the bioactivity of ponicidin in the blood of mice was evaluated, the substance showed relatively long-lasting effects on the potentiation of the anti-herpetic and cytotoxic activities of GCV after intravenous administration. These data suggest that the combined use of ponicidin with GCV will be effective for cancer gene therapy, because high cytotoxicity in viral TK-expressing cells should yield more rapid and enhanced tumor elimination.
Cancer Gene Ther 2000 Jan;7(1):45-52 Potentiation of ganciclovir toxicity in the herpes simplex virus thymidine kinase/ganciclovir administration system by ponicidin. Hayashi K, Hayashi T, Sun HD, Takeda Y Department of Virology, Toyama Medical and Pharmaceutical University, Japan.Rabdosia
Rabdosia rubescens (donglingcao), formerly called Isodon rubescens, is a rarely-used Chinese herb (the entire plant is used). Its traditional use is as a digestant and anti-inflammatory agent, but it has been a folk remedy for carcinomas of the heart and esophagus in Hunan Province (4). Laboratory animal studies demonstrate notable antineoplastic properties. The main active components are oridonin (the main one studied) and similar compounds such as ponicidin (these active constituents are tetracyclic diterpenoid compounds). Little toxicity has been noted (5, 6). Early clinical reports indicated benefits of the herb for esophageal cancer and it has been tried with some other types of cancer. More recently, the active constituent oridonin has been evaluated as adjunct to standard cancer therapies, such as cisplatin, in tissue culture and in laboratory animal studies (7, 11). In a review of investigations on rabdosia (12) spanning the 1950s to the present, no mention is made of hormonal effects. In the book Anticancer Medicinal Herbs, rabdosia is mentioned under its earlier botanical name Isodon. Recommended dosages are 90-120 grams of the fresh herb (this corresponds, roughly, to 30-40 grams of dried herb), and 30 grams of the dried herb. It is mentioned, at the latter dosage, as being useful for cancer of the breast (when combined with other herbs). The author of the book mentioned that "The Tumor Department of the First Teaching Hospital of Henan Medical College has used the tablets [of ginseng plus rabdosia] for years and their experience indicates that the tablet is one of the best drugs for breast cancer." Panax notoginseng, a relative of ginseng, is reportedly contained in the PC-SPES formula. Despite this glowing report from more than a decade ago, the limited discussion of Chinese herbal treatments for breast cancer does not seem to follow-up on it. Nonetheless, rabdosia appears interesting since it purportedly benefits the digestive system, inhibits cancer, and is low in toxicity. As a reflection of this interest, in the book Chinese Drugs of Plant Origin (17), of 120 herb entries, rabdosia has one of the largest sections. There are two dozen pages of chemical constituent illustrations, obtained as a result of efforts to find the most useful antitumor agents from the many species of Rabdosia that grow in China
Contribution of a combination of ponicidin and acyclovir/ganciclovir to the antitumor efficacy of the herpes simplex virus thymidine kinase gene therapy system.
Hayashi K, Hayashi T, Sun HD, Takeda Y.
Department of Virology, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan. khayashi@ms.toyama-med.ac.jp
We have previously reported that ponicidin (PND), isolated from Rabdosia ternifolia, potentiates the cell-killing activity of antiherpes prodrugs acyclovir (ACV) and ganciclovir (GCV) in human cancer cells expressing herpes simplex <<<More>>>
Olive Leaf extrac
Jul 4
Olive Leaf extract
Olive Leaf Health Benefits
Olive leaf (oleuropein) has been shown to have a variety of health benefits.
Life Sci 1998;62(6):541-6 Oleuropein, the bitter principle of olives, enhances nitric oxide production by mouse macrophages. Visioli F, Bellosta S, Galli C. Institute of Pharmacological Sciences, Milan, Italy. Francesco.Visioli@unimi.it "The Mediterranean diet, rich in fresh fruits and vegetables, has been associated with a lower incidence of cardiovascular disease and cancer, partly because of its high proportion of bioactive compounds such as vitamins, flavonoids and polyphenols. The major lipid component of such diet is the drupe-derived olive oil, that can be distinguished from other seed oils for the peculiar composition of its non-triglyceride fraction. In fact, several minor components, including polyphenols, grant the oil its particular taste and aroma. Oleuropein, the most abundant among these components, has been shown to be a potent antioxidant endowed with antiinflammatory properties. We investigated the effects of oleuropein on NO release in cell culture and its activity toward nitric oxide synthase (iNOS) expression. The results show that oleuropein dose-dependently enhance nitrite production in LPS-challenged mouse macrophages. This effect was blocked by the iNOS inhibitor L-NAME, indicating increased iNOS activity. Also, Western blot analysis of cell homogenates show that oleuropein increases iNOS expression in such cells. Taken together, our data suggest that, during endotoxin challenge, oleuropein potentiates the macrophage-mediated response, resulting in higher NO production, currently believed to be beneficial for cellular and organismal protection."
J Pharm Pharmacol 1999 Aug;51(8):971-4 On the in-vitro antimicrobial activity of oleuropein and hydroxytyrosol. Bisignano G, Tomaino A, Lo Cascio R, Crisafi G, Uccella N, Saija A. Department Farmaco-Biologico, University of Messina, Italy. "Secoiridoides (oleuropein and derivatives), one of the major classes of polyphenol contained in olives and olive oil, have recently been shown to inhibit or delay the rate of growth of a range of bacteria and microfungi but there are no data in the literature concerning the possible employment of these secoiridoides as antimicrobial agents against pathogenic bacteria in man. In this study five ATCC standard bacterial strains (Haemophilus influenzae ATCC 9006, Moraxella catarrhalis ATCC 8176, Salmonella typhi ATCC 6539, Vibrio parahaemolyticus ATCC 17802 and Staphylococcus aureus ATCC 25923) and 44 fresh clinical isolates (Haemophilus influenzae, eight strains, Moraxella catarrhalis, six strains, Salmonella species, 15 strains, Vibrio cholerae, one strain, Vibrio alginolyticus, two strains, Vibrio parahaemolyticus, one strain, Staphylococcus aureus, five penicillin-susceptible strains and six penicillin-resistant strains), causal agents of intestinal or respiratory tract infections in man, were tested for in-vitro susceptibility to two olive (Olea europaea) secoiridoides, oleuropein (the bitter principle of olives) and hydroxytyrosol (derived from oleuropein by enzymatic hydrolysis and responsible for the high stability of olive oil). The minimum inhibitory concentrations (MICs) calculated in our study are evidence of the broad antimicrobial activity of hydroxytyrosol against these bacterial strains (MIC values between 0.24 and 7.85 microg mL(-1) for ATCC strains and between 0.97 and 31.25 microg mL(-1) for clinically isolated strains). Furthermore oleuropein also inhibited (although to a much lesser extent) the growth of several bacterial strains (MIC values between 62.5 and 500 microg mL(-1) for ATCC strains and between 31.25 and 250 microg mL(-1) for clinical isolates); oleuropein was ineffective against Haemophilus influenzae and Moraxella catarrhalis. These data indicate that in addition to the potential employment of its active principles as food additives or in integrated pest-management programs, Olea europaea can be considered a potential source of promising antimicrobial agents for treatment of intestinal or respiratory tract infections in man."
Life Sci 1994;55(24):1965-71 Oleuropein protects low density lipoprotein from oxidation. Visioli F, Galli C. University of Milan, Institute of Pharmacological Sciences, Italy. "The Mediterranean diet, rich in fruit, vegetables, grain, and vegetable oil (mainly olive oil) is correlated with a lower incidence of coronary heart disease (CHD). Natural antioxidants contained in the Mediterranean diet might also play a role in the prevention of cardiovascular diseases, through inhibition of LDL oxidation. We tested this hypothesis "in vitro" by inducing LDL oxidation with copper sulphate and preincubating the samples with oleuropein, the bitter principle of olives, that is one of the major components of the polyphenolic fraction of olive oil. Oleuropein 10(-5) M effectively inhibited CuSO4-induced LDL oxidation, as assessed by various parameters. We demonstrate in this investigation that polyphenolic components of the Mediterranean <<<More>>>
Nonoxyl
Jul 3
Nonoxyl
Nonoxyl-9 can be a potent anti-viral when used infrequently, however it is not recommended as an antiviral as it tends to cause irritation to the vaginal lining, thus eliminating it’s benefits and sometimes even increasing risk of STD transmission.
But whichever agent is used, it is vital that it doesn’t have the side effect that brought down a once-promising product called nonoxynol-9. This surfactant, originally developed as a spermicide, was shown to destroy HIV in the lab. Because several nonoxynol-9 formulations had been on the market for decades as vaginal contraceptives, they seemed like obvious microbicide candidates.
Unfortunately, clinical trials showed that in the real world they offered no protection against HIV. If used more than about three times daily they could even increase HIV transmission. This is because nonoxynol-9 damages the mucosal layer of the vagina, leaving the underlying immune cells exposed to the virus. The rectal mucosa is damaged even more by this surfactant. To many in the field these findings came as no great surprise, because some research had already suggested nonoxynol-9 may harm epithelial cells. But the result was disappointing because, had it worked, nonoxynol-9 could have quickly been made widely available, saving many lives.
Excerpt from MICROBICIDES: A NEW APPROACH TO PREVENTING HIV AND OTHER SEXUALLY TRANSMITTED INFECTIONS by Alan Stone:
… In the Nairobi trial, the product being tested was a commercially available contraceptive sponge impregnated with 1,000 mg of nonoxynol-9. The outcome was disappointing: the product did not protect against HIV, gonorrhoea or chlamydia, and seemed to be responsible for genital ULCERS in some of the women10. Several subsequent Phase III trials of different nonoxynol-9 formulations also failed to show any benefit. These included a study in the Cameroon of a vaginal contraceptive film incorporating 70 mg of nonoxynol-9 (Ref. 12) and a trial of a contraceptive gel (known as COL-1492) containing 52.5 mg of the substance, which was carried out in several African sites13. In the latter trial, use of the surfactant was associated with a significant increase in the incidence of HIV infection. This was particularly pronounced among the women who were more frequent users of the product (mean use >3.5 times a day), and in the same group, there was a higher incidence of genital ulcers than in the equivalent placebo group. In neither trial was there an effect on gonorrhoea or chlamydia infection rates. It is unclear why the earlier safety studies with COL-1492 failed to show an excess of ulcers14, but this was probably because of their short duration and insufficient power to detect an effect of the size seen in Phase III studies. In a further study carried out in the Cameroon, a different gel containing 100 mg nonoxynol-9 also failed to protect women against the two bacterial infections (HIV was not a primary end point in this trial)15.
After the initial announcement of the COL-1492 result in 2000, several national and international bodies issued statements advising on its implications for the use of nonoxynol-9 in both stand-alone products and condom coatings. In June 2002, the World Health Organization released a report containing the recommendations of a meeting of experts who had concluded, after careful scrutiny of all the available evidence on the potential benefits and hazards of nonoxynol-9, that this substance should not be used as a microbicide (although it remains a contraceptive option for women at low risk of HIV)16. The report stresses that alternative microbicides, which are safe and effective, need to be developed as a matter of urgency.
There is insufficient information to be able to offer definitive guidance about the value of other surfactants as microbicides, although research is continuing with a number of them. For example, C31G, an equimolar mixture of the amphoteric surfactants cetyl betaine and myristamine oxide, has successfully completed a Phase I safety study (A.-M. Corner, personal communication).
To understand why nonoxynol-9 failed to protect against HIV in the above trials, and why there is considerable optimism about the eventual success of some of the alternative microbicides that are under investigation at present, we need to consider the biological mechanism by which HIV is transmitted sexually. Potential sources of transmissible HIV are free virus particles and infected LYMPHOID CELLS in semen, in cervicovaginal secretions and in <<<More>>>
