DISCUSSION AND CONCLUSION ON TESTOSTERONE AND ERECTILE DYSFUNCTION

The treatment of erectile dysfunction, present special challenges which include late presentation, in availability of drugs, high cost and intolerable side effect of drugs. In response to the above challenges, there has been a renewed interest in medicinal plants in the treatment of sexual dysfunction, which are being shown to be both effective and safe. Several medicinal plants have been used to treat many ailments including sexual dysfunction. Ginseng and other herbal remedies are used for the treatment of erectile dysfunction include: crushed seeds of fennel, licorice, pollen, sarsaparilla, asafetida, hops and Spanish fly (Adimoelja, 2000; Guirguis, 1998).  Acacia polyacantha is one of the medicinal plants that is being used in the tradition treatment of erectile dysfunction. To the best of our knowledge there is no scientific evidence to support the use of Acacia polyacantha to enhance sexual performance.

The (LD₅₀) of the plant extract was calculated to be 3807.9 mg/kg indicating that the plant extract is relatively safe.

There was no significant difference in mounting frequency between the Viagra, the control and the extract treated groups. But at the dose f 150 mg/kg of the extract treated group present a biphasic action.

The three groups treated with different doses of aqueous methanolic stem bark extract of Acacia polyacantha at 150, 300 and 600 mg/kg when compared with Viagra treated group, did not show a significant difference in sperm count and sperm motility. However the result of the sperm morphology of the extract treated groups 150, 300, and 600 mg/kg showed a significant increase (p<0.05) in normal sperm morphology when compared to that of Viagra 5 mg/kg.

The three doses of the extract tend to elevate serum testosterone level when compared with the Viagra treated group.

The seminiferous tubules, the primary spermatocytes up to the spermatids are well define in the control. There was an increase in elongated spermatids arising from the secondary spermatocytes toward the lumen of the seminiferous tubules in the Viagra treated group. The elongated spermatid seen towards the lumen is as a result of increase in spermatogenesis. The groups that were treated with the doses of 150, 300 and 600 mg/kg of the extract had a reduced number of primary spermatocytes with increase in the number of spermatids toward the lumen of the seminiferous tubules as a result of increase in spermatogenesis.

The effect produced by the plant extract in the aforementioned parameters is possible due to the presences of flavonoid which according to Harbourne, (1993), Igile  et al.,(1994) and Evans, (1999) posses anti –oxidant effect. The preliminary Phytochemical studies of the aqueous methanolic stem bark extract of acacia polyacantha revealed the presence of  other compounds such as tannins, anthraquinones, steroids, triterpenes, cardiac glycosides, saponins and alkaloids.

A number of herbal plants such as Securidaca longepeduculata (polygalaceae), Wrightia natalensis (Apocynaceae), and Rhoicissas tridentate L.F (wild and R.B Drumm) (vitaceae) are used in treatment of erectile dysfunction. While plants such as Curcuma longa and Garcia kola  enhance sperm motility and decrease spermatozoa abnormality  (Ishihara et al., 2000), (Farombi et al., 2007), Tribulus terristis (Adimoeja et al.,1995), Asparagus racemous, Withania senticosus, Andrographis paniculata and acanthopanax sensticosus (Nantia et al., 2009) are  plants proven to improve spermatogenesis, sperm mortility and morphology. Many flavonoids containing plants are know to have anti –oxidant effect, as quoted by Harborne (1993) and Evans (1999).

CONCLUSION

Based on the findings of this study, it is concluded that; the stem bark extract Acacia polyacantha did not significantly affect mounting frequency, sperm count, sperm motility and serum testosterone level in adult rats. But however, it significantly raised the number of   normal sperm morphology suggesting a modulatory effect of Acacia polyacantha which may be caused by the presence of Flavonoids which has an anti-oxidant property [Harbourne, (1993), Igile et al., (1994), Evans (1999) .

RECOMMENDATION

These preliminary results can be seen as the groundwork for further studies which can be carried out to isolate and identify the active chemical constituent of Acacia polyacantha  and their possible mechanism of action on isolated cavernous tissue , so that it can  be used as an alternative in the treatment of reproductive related issues. Hence the local users of this plant could be advised on its usage for local ailments and the required dose based on the LD_50.

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