Sexual Behavior of Tribulus Terrestris

Many of today’s popular dietary supplements come from plants that have been used medicinally since ancient times. One of these botanicals is Tribulus terrestris, which is purported to have a variety of health benefits, including reduced blood sugar, cholesterol, altered hormone levels and increased sexual function and libido. Tribulus terrestris is normally distributed in tropical and subtropical countries in Asia, Africa, south Europe, North Australia and introduced in new world tropics. In UAE common and widespread in Urban areas, roadsides and depressions receiving runoff water (Figure 1) [1]. In UAE the plant is used by some healers as an aphrodisiac, diuretic and hypotensive also used to treat dysuria; it is soothing, analgesic, diuretic, tonic, against colic . The leaves of the plant used to treat enlarged spleen, puerperal fever, sores, diarrhea, nervous exhaustion and cramps, normally the whole plant is used. A transverse section of the stem from the periphery to the pith shows the following: an epidermal layer consisting of small ovoid cells with thick cell walls and the epidermis is covered with thick cuticle.


Introduction
Many of today's popular dietary supplements come from plants that have been used medicinally since ancient times. One of these botanicals is Tribulus terrestris, which is purported to have a variety of health benefits, including reduced blood sugar, cholesterol, altered hormone levels and increased sexual function and libido.
Tribulus terrestris is normally distributed in tropical and subtropical countries in Asia, Africa, south Europe, North Australia and introduced in new world tropics. In UAE common and widespread in Urban areas, roadsides and depressions receiving runoff water ( Figure 1) [1]. In UAE the plant is used by some healers as an aphrodisiac, diuretic and hypotensive also used to treat dysuria; it is soothing, analgesic, diuretic, tonic, against colic . The leaves of the plant used to treat enlarged spleen, puerperal fever, sores, diarrhea, nervous exhaustion and cramps, normally the whole plant is used.
A transverse section of the stem from the periphery to the pith shows the following: an epidermal layer consisting of small ovoid cells with thick cell walls and the epidermis is covered with thick cuticle. Attached to the epidermis are numerous one-celled covering trichomes that have comparatively wide lumens and thick cell walls.
The epidermis is encircling several layer of cortical colenchyma (about 6-7 layers); the inner layers enclose groups of lignified fibres that have thick cell walls and narrow lumens. The cortex encircles phloem tissues, heavily lignified xylem tissues (vessels, trachieds and fibres) and at the centre are the nearly rounded parenchyma cells of the pith which occupy a wide zone ( Figure 2).

Physicochemical Constituents (%)
Physico chemical constituents carried out on the plant Tribuls terrestris are as follows: Elemental Analyses (Table 1).    Thin layer Chromatography (TLC)  The best-known member is T. terrestris (Puncture Vine), a widespread weed and also the source of a dietary supplement claimed to increase the body's natural testosterone levels and thereby improve male sexual performance and help build muscle.
T. terrestris has consistently failed to increase testosterone levels in controlled studies [13][14][15]. It has also failed to demonstrate strength-enhancing properties [16]. Tribulus has been shown to enhance sexual behaviour in an animal model. It appears to do so by stimulating androgen receptors in the brain [17]. Jameel, et al. [18] reported a case of a young weight-trainer who developed gynaecomastia due to oral intake of an herbal tablet which he used as a steroid alternative for body-building. The aqueous extract of Tribulus terrestris can significantly increase melanocyte-stimulating hormone (MSH) expression in the hair follicle melanocytes by activating tyrosinase activity and promoting melanocyte proliferation, melanine synthesis, and epidermal migration of dormant melanocytes [19]. Tribulus terrestris showed protective effect for STZ-induced diabetic rats may be mediated by inhibiting oxidative stress [20].
Sharif, et al. [21] investigated the antihypertensive mechanism of Tribulus in 2K1C hypertensive rats by measurement of circulatory and local ACE activity in aorta, heart, kidney and lung.
The ACE activity in all tissues of Tribulus fed hypertensive rats was significantly lower than that of hypertensive rats, which was more pronounced in kidney. These results indicated that there is a negative correlation between consumption of Tribulus and ACE activity in serum and different tissues in 2K1C rats. Oludotun, et al. [22] reported the effects of methanolic and aqueous extracts of Tribulus terrestris on rat blood pressure (BP) and the perfused mesenteric vascular bed were investigated. The extracts dosedependently reduced BP in spontaneously hypertensive rats (SHRs) with the aqueous fraction being more potent than the methanolic fraction at all doses tested. In vitro, the methanolic but not aqueous extract produced a dose-dependent increase in perfusion pressure of the mesenteric vascular bed. When perfusion pressure was raised with phenylephrine, the aqueous extract produced a dosedependent reduction in perfusion. It was concluded that methanolic and aqueous extracts of Tribulus terrestris possess significant antihypertensive activity in spontaneously hypertensive rats.  Table 3).

Conclusion
The oral administration of the plant extract was non-toxic up to the dose of 10 g/kg b.wt., p.o. These acute studies demonstrated that the plant extract is safe and did not cause any detrimental effects in vivo under the conditions investigated in this study. The LD50 of plant extract was found to be >10 g/kg when administered once via gastric intubation to rats. Plant extract produced a mild relaxation in phenylephrine pre-contracted corpus cavernous tissue.