TRIBESTAN EFFECT ON THE CONCENTRATION OF SOME HORMONES IN THE SERUM OF HEALTHY SUBJECTS

S. Milanov, A. Maleeva, M. Taskov

RIRR - Radioisotope and Radioimmunological Laboratory, Sofia

Chemical Pharmaceutical Research Institute,
Sofia, Bulgaria

SUMMARY

Tribestan effect has been studied on the serum concentration of hypophyseal hormones, of ACTH, STH, LH, FSH, adrenal hormone aldosterone and cortisol and sex hormones - testosterone and estradiol. The experiments have been carried out on 8 males and 8 females, aged 28 - 45 years of age. The product was perorally administered in a single dose of 250 mg, three times daily for 5 days. Serum samples were withdrawn at 8 a.m. and 12 a.m., prior to and post treatment. The product has been established not to change essentially the concentrations of adrenal hormones and of ACTH. The hypophyseal-gonadal axis however has significantly been affected in the females with predominantly increased concentration of FSH and estradiol and in the males - mainly of LH and the testosterone. The mechanism of that action is presumed to be complicated and realized both by direct effect on gonadal apparatus and by the tropic hormones.
The probable established changes in the concentration of the hormones studied do not get out of the frames of the physiological limits.

The lyophilized extract of Tribulus terrestris, introduced in veterinary practice as TB-68, has pronounced sex-stimulating function. The initial studies of this product showed that it stimulates the spermatogenesis of albino rats (Vankov S., et al., 1973) and enhanced the ovulation of female rats (Vankov S. et al. 1973). Zarkova S. (1976) has also established in rats an increased number of spermatogonia, spermatocytes as well as increase of neutral mucopolysaccharides in seminiferous tubules of the testes. Gendzhev Z. and S. Zarkova, in other experiments (1978) proved the increase of spermatic reserve in the epididymis of rats.

With the view to the need of human medicine of a product stimulating sexual function, Tribestan was formulated on the base of the indicated phytochemical product. It contains saponins of furostanol type (Tomova M. et al., 1978). The first studies of Tribestan confirmed its high sex-stimulating activity in experimental animals (Zarkova S., 1981). Later, the clinical studies established a similar stimulating effect in humans as well (Protich M. at al. 1981). The present study was carried out with a view to throwing light on some aspects of the mechanism of that action of Tribestan, aiming at attaining an effect from the product on the serum concentration of some hypophyseal, sexual and adrenal hormones.

MATERIALS AND METHODS

The experiments were performed on 16 subjects (8 females and 8 males), aged 28-45. All subjects were in good health, without any complaints and good capacity for work. The following schedule was used:
1. The basic levels of hypophysiotropic hormones (ACTH, STH, LH, FSH), of sexual hormones (testosterone and estradiol) and of adrenal hormones (aldosterone and cortisol) were determined. They were determined twice, at 8 a.m. and 12 p.m. - one day prior to Tribestan treatment.
2. The treatment with the product was initiated on the following day, which was periodically administered, 250 mg, three times daily for 5 days.
3. After the termination of Tribestan treatment (day sixth after the initiation of the experiment), blood was again withdrawn (at the same hour - 8:00 a.m. and 12 p.m.) for the determination of the concentration of the indicated hormones.

The work proceeded in the following way: after centrifugation of 6 - 8 ml blood, the serum obtained was frozen at 20°C till the day of the determination of hormonal concentration. The determination was performed by radioimmune tests. LH and FSH were determined by the modified method of Midgley A.R., (1967), making use of some kits of Biodata company, Italy and ACTH and STH - according to the method of Berson S.A. and R. S. Yalow (1963). Testosterone was evaluated by the method of William R. H. (1968), and of estradiol by Orezyk G.P. et al. (1974), making use of kits of Sorin Company, Belgium for both hormones. The adrenal hormones cortisol and aldosterone were also determined by kits of that company, making use of Vescei P. (1974) and of William G and R. Hunderwood (1974).

The obtained results were statistically processed by variation analysis, by Student - t test.

RESULTS AND DISCUSSION

As could be seen from Table 1, LH level in the males was elevated with a high significance after the treatment (p < 0.001). The changes affected both samples to the same rate (at 8 a.m. and 12 p.m.). FSH concentration was not affected under the same conditions. The other two hypophyseal hormones, ACTH and STH were not changed.

An insignificant tendency to elevation was observed in STH level (mean values - 2.9 prior to and 3.2 mg/ml post treatment) in some of the cases. The level of sex hormones was strongly affected. Thus testosterone concentration was three-fold (2) increased and that of estradiol - about 1.5 times (Table 1).

LH concentration was also increased in females under Tribestan effect. What impressed was that the significance was lower than the first sample. The greatest discrepancy, as compared with the results of the males, was the sharp stimulation of FSH. A strong effect was observed there, which could be explained by blood withdrawal during the early phase of the menstrual cycle, the so-called follicular phase. Estradiol was also strongly affected (Pt < 0.001), whereas testosterone in the females during the early hours of the day was less affected (Table 2).

The level of adrenal hormone was identically affected both in males and females (Table 3). A significant increase of the concentration was also established though that effect had a relatively low significance (p < 0.05). At the same time, cortisol level was no changed (Table 3).

The results obtained provided grounds to admit that Tribestan had a pronounced stimulating effect on the secretion of some hormones. The effect on the hormones along the hypophyseal-gonadal axis was particularly well manifested. The effect was manifested both at hypophyseal and gonadal level. Some sexual discrepancies were also established. Thus, FSH was mainly affected in the females. The presence of that hormone is exceptionally important during the follicular phase for the development of the follicle. When its development is stimulated, its secretory ability is also intensified and hence - estradiol level is elevated. Lutenizing hormone is more strongly influenced in the male, which on its part stimulates the secretion of testosterone.

ACTH and cortisol were not changed suggesting that they were not significantly involved in the realization of Tribestan effects. The tendency of stimulation of STH and aldosterone explained the activation of the anabolic processes in the body and general stimulating action of the product. The absence of effect on the level of cortisol showed however that the general tonic action was very strongly manifested.

It should be stressed that the level of the hormones studied did not go out beyond the physiological frames i.e. it did not disturb the physiological mechanisms of hormonal regulation.

References

1. Vankov S., S. Zarkova, Z. Gendzhev, M. Tomova - Effect of TB-68 on the spermatogenesis in albino rats. Proceeding of the Third National Conference of Pharmacology and Clinics of New Bulgarian Drugs, Sofia, November 14-16, 1973, v.2, 161-163.
2. Vankov S., S. Zarkova, M. Tomova - TB-68 effect on ovulation of albino rats. Proceedings of Third National Conference of Pharmacology and Clinics of New Bulgarian Drugs, Sofia, November 14-16, 1973, v.2, 165-167.
3. Gendzhev Z., S. Zarkova - Effect of the phyto-pharmaceutical TB-68 on the number of spermatozoa in epididymis of rat. Med. Archive, 1978, N I, 113-118.
4. Dimova P., M. Taskov - Comparative enzyme-histological studies of some phyto-products. MBI (at the printer's), 1981.
5. Zarkova S. - Morphological and histological changes in testes of rat under the effect of TB-68, Med. Archive, 1976, N 4, 49-53.
6. Protich M., D. Zvetanov, V. Nalbanski, R.Stanislavov, M.Kazarova - Clinical trial of Tribestan on infertile males, MBI (at the printer's).
7. Tomova M., V. Gyulemetova, S. Zarkova - Author's certificate N 77584 A 61 K 35/1978.
8. Berson S.A., R. S. Yalow - Immunoassay of protein hormones, The Hormones, Vol. V, Acad. Press., New York, 1963.
9. Midgley A.R. - Radioimmunoassay for Human, J. Clin. Endocr., 1967, 27, 295.
10. Orezyk, Gaylo P., Burton v. Caldwell, Harold H. Behrmaan - Methods of Hormone Radioimmunoassay - Ed. B. Jaffe, H. Berhmaan, A6. Press, NJ, London, 1974, 333-343.
11. Vescei P. - Glicocorticoids: Cortisol Corticosterone - Methods of Hormone Radioimmunoassay; Ed. B. Jaffe and H. Behrmaan, Ac. Press, NJ, London 393-412.
12. William R.H. - Textbook of Endocrinology 4th Edit. Saunder, Philadelphia, 1968.
13. Williams Gordon H., Richard H. Hunderwood - Methods of Hormon Radioimmunoassay; Ed. B. Jaffe and H. Behrmaan, Ac. Press, NJ, London, 1974, 371-390.

NOTES BELOW ARE NOT PART OF ORIGINAL DOCUMENT

Corrections:

1. Corrected value to 14.38 where previous value erroneously published was 14.28. (Date of correction 01/16/2002.
2. Inconsistency in the statement three-fold and table values. Corresponds to English translated document. Needs comparison with original document in Bulgarian language. Further investigation underway.