Tribulus :
Hormonal effects of Tribulus terrestris (TT) were evaluated in primates, rabbit and rat to identify its usefulness in the management of erectile dysfunction (ED). TT extract was administered intravenously, as a bolus dose of 7.5, 15 and 30mg/kg, in primates for acute study. Rabbits and normal rats were treated with 2.5, 5 and 10mg/kg of TT extract orally for 8 weeks, for chronic study. In addition, castrated rats were treated either with testosterone cypionate (10mg/kg, subcutaneously; biweekly for 8 weeks) or TT orally (5mg/kg daily for 8 weeks). Blood samples were analyzed for testosterone (T), dihydrotestosterone (DHT) and dehydroepiandrosterone sulphate (DHEAS) levels using radioimmunoassay. In primates, the increases in T (52%), DHT (31%) and DHEAS (29%) at 7.5mg/kg were statistically significant. In rabbits, both T and DHT were increased compared to control, however, only the increases in DHT (by 30% and 32% at 5 and 10mg/kg) were statistically significant. In castrated rats, increases in T levels by 51% and 25% were observed with T and TT extract respectively that were statistically significant. TT increases some of the sex hormones, possibly due to the presence of protodioscin in the extract. TT may be useful in mild to moderate cases of ED.
OBJECTIVE: The present study was undertaken to investigate the effect of Tribulus alatus extracts on free serum testosterone in male rats. MATERIALS AND METHODS: Free serum testosterone level was measured in male rats treated with alcoholic extracts of the aerial part without fruits, fruits of Tribulus alatus and their fractions. RESULTS: All tested extracts showed significant increase in the level of free serum testosterone when compared to that of corresponding control, p < 0.05. Statistical comparison of all groups revealed that the maximum level was found in groups treated with chloroformic and ethanolic fractions of fruits extract. CONCLUSION: Tribulus alatus extract appears to possess aphrodisiac activity due to its androgen increasing property.
Tribulus terrestris is an herbal nutritional supplement that is promoted to produce large gains in strength and lean muscle mass in 5-28 days (15, 18). Although some manufacturers claim T. terrestris will not lead to a positive drug test, others have suggested that T. terrestris may increase the urinary testosterone/epitestosterone (T/E) ratio, which may place athletes at risk of a positive drug test. The purpose of the study was to determine the effect of T. terrestris on strength, fat free mass, and the urinary T/E ratio during 5 weeks of preseason training in elite rugby league players. Twenty-two Australian elite male rugby league players (mean +/- SD; age = 19.8 +/- 2.9 years; weight = 88.0 +/- 9.5 kg) were match-paired and randomly assigned in a double-blind manner to either a T. terrestris (n = 11) or placebo (n = 11) group. All subjects performed structured heavy resistance training as part of the club's preseason preparations. A T. terrestris extract (450 mg.d(-1)) or placebo capsules were consumed once daily for 5 weeks. Muscular strength, body composition, and the urinary T/E ratio were monitored prior to and after supplementation. After 5 weeks of training, strength and fat free mass increased significantly without any between-group differences. No between-group differences were noted in the urinary T/E ratio. It was concluded that T. terrestris did not produce the large gains in strength or lean muscle mass that many manufacturers claim can be experienced within 5-28 days. Furthermore, T. terrestris did not alter the urinary T/E ratio and would not place an athlete at risk of testing positive based on the World Anti-Doping Agency's urinary T/E ratio limit of 4:1.
The steroidal saponins of Tribulus terrestris L. (Zygophyllaceae) are considered to be the factor responsible for biological activity of products derived from this plant. The activity depends on the concentration and the composition of active saponins, which in turn is influenced by the geographical origin of plant material. Samples of T. terrestris collected in Bulgaria, Greece, Serbia, Macedonia, Turkey, Georgia, Iran, Vietnam and India were analyzed by LC-ESI/MS/MS for the presence and the concentration of protodioscin (1), prototribestin (2), pseudoprotodioscin (3), dioscin (4), tribestin (5) and tribulosin (6). The flavonoid rutin (7) was also included in the comparison. The results revealed distinct differences in the content of these compounds depending on region of sample collection, plant part studied and stage of plant development. The samples from Bulgaria, Turkey, Greece, Serbia, Macedonia, Georgia and Iran exhibited similar chemical profile and only some quantitative difference in the content of 1-7 with protodioscin (1) and prototribestin (2) as main components. The Vietnamese and Indian samples exhibit totally different chemical profile. They lack 2 and 5, while tribulosin (6) is present in high amounts. Compounds different from 1 to 7 are dominating in these 3 samples. The presented results suggested the existence of one chemotype common to the East South European and West Asian regions. Most probably, the Vietnamese and Indian samples belong to other chemotypes which are still to be studied and characterized. No clear correlation between the burrs morphology and the chemical composition of the samples has been found.
OBJECTIVE: This study investigated the effects of four weeks of intake of a supplement containing dehydroepiandrosterone (DHEA), androstenedione and herbal extracts on immune function in middle-aged men. DESIGN: Subjects consumed either an oral placebo or an oral supplement for four weeks. The supplement contained a total daily dose of 150 mg DHEA, 300 mg androstenedione, 750 mg Tribulus terrestris, 625 mg chrysin, 300 mg indole-3-carbinol and 540 mg saw palmetto. MEASUREMENTS: Peripheral blood mononuclear cells were used to assess phytohemagglutinin(PHA)-induced lymphocyte proliferation and cytokine production. The cytokines measured were interleukin (IL)-2, IL-4, IL-10, IL-1beta, and interferon (IFN)-gamma. Serum free testosterone, androstenedione, estradiol, dihydrotestosterone (DHT) were also measured. RESULTS: The supplement significantly increased serum levels of androstenedione, free testosterone, estradiol and DHT during week 1 to week 4. Supplement intake did not affect LPS or ConA proliferation and had minimal effect on PHA-induced proliferation. LPS-induced production of IL-1beta, and PHA-induced IL-2, IL-4, IL-10, or IFN-gamma production was not altered by the supplement. The addition of the same supplement, DHEA or androstenedione alone to lymphocyte cultures in vitro did not alter lymphocyte proliferation, IL-2, IL-10, or IFN-gamma, but did increase IL-4. In addition, serum HDL-C concentration significantly declined. CONCLUSION: These findings suggest that, although chronic intake of a complex dietary supplement containing DHEA, androstenedione and herbal extracts increases serum androgen levels, it has minimal effect on immune function in middle-aged men
The effects of androgen precursors, combined with herbal extracts designed to enhance testosterone formation and reduce conversion of androgens to estrogens was studied in young men. Subjects performed 3 days of resistance training per week for 8 weeks. Each day during Weeks 1, 2, 4, 5, 7, and 8, subjects consumed either placebo (PL; n = 10) or a supplement (ANDRO-6; n = 10), which contained daily doses of 300 mg androstenedione, 150 mg DHEA, 750 mg Tribulus terrestris, 625 mg Chrysin, 300 mg Indole-3-carbinol, and 540 mg Saw palmetto. Serum androstenedione concentrations were higher in ANDRO-6 after 2, 5, and 8 weeks (p <.05), while serum concentrations of free and total testosterone were unchanged in both groups. Serum estradiol was elevated at Weeks 2, 5, and 8 in ANDRO-6 (p <.05), and serum estrone was elevated at Weeks 5 and 8 (p <.05). Muscle strength increased (p <.05) similarly from Weeks 0 to 4, and again from Weeks 4 to 8 in both treatment groups. The acute effect of one third of the daily dose of ANDRO-6 and PL was studied in 10 men (23 +/- 4 years). Serum androstenedione concentrations were elevated (p <.05) in ANDRO-6 from 150 to 360 min after ingestion, while serum free or total testosterone concentrations were unchanged. These data provide evidence that the addition of these herbal extracts to androstenedione does not result in increased serum testosterone concentrations, reduce the estrogenic effect of androstenedione, and does not augment the adaptations to resistance training
Tribulus terrestris (TT) has long been used in the traditional Chinese and Indian systems of medicine for the treatment of various ailments and is popularly claimed to improve sexual functions in man. Sexual behaviour and intracavernous pressure (ICP) were studied in both normal and castrated rats to further understand the role of TT containing protodioscin (PTN) as an aphrodisiac. Adult Sprague-Dawley rats were divided into five groups of 8 each that included distilled water treated (normal and castrated), testosterone treated (normal and castrated, 10 mg/kg body weight, subcutaneously, bi-weekly) and TT treated (castrated, 5 mg/kg body weight, orally once daily). Decreases in body weight, prostate weight and ICP were observed among the castrated groups of rats compared to the intact group. There was an overall reduction in the sexual behaviour parameters in the castrated groups of rats as reflected by decrease in mount and intromission frequencies (MF and IF) and increase in mount, intromission, ejaculation latencies (ML, IL, EL) as well as post-ejaculatory interval (PEI). Compared to the castrated control, treatment of castrated rats (with either testosterone or TT extract) showed increase in prostate weight and ICP that were statistically significant. There was also a mild to moderate improvement of the sexual behaviour parameters as evidenced by increase in MF and IF; decrease in ML, IL and PEI. These results were statistically significant. It is concluded that TT extract appears to possess aphrodisiac activity probably due to androgen increasing property of TT (observed in our earlier study on primates).
