CHAPTER ONE
1.0 INTRODUCTION
Procreation is an important moral and religious issue and aphrodisiacs are sought to ensure both male and female potency. Sexual potency is part of the male ego, the anxiety and the humiliation that are associated with a declining sexual ability are common to all cultures. That is why the popularity of aphrodisiacs has not shown any sign of decline throughout history. Successful treatment of sexual dysfunction may improve not only sexual relationships, but also the overall quality of life. Enhanced sexual behavior may provide increased relationship satisfaction and self-esteem in humans (Baldwin et al., 2003).
Sexual dysfunction is an inability to achieve a normal sexual intercourse, including premature ejaculation, retrograded, retarded or inhibited ejaculation, erectile dysfunction, arousal difficulties (reduced libido), compulsive sexual behavior, orgasmic disorder, and failure of detumescence. The introduction of the first pharmacologically approved remedy for impotence, Viagra (sildenafil) in 1990s caused a wave of public attention, propelled in part by heavy advertising. The search for such substances dates back millennia.
An aphrodisiac is defined as any food or drug that arouses the sexual instinct, induces veneral desire and increases pleasure and performance. Aphrodisiacs can be classified by their mode of action into three types: Those that increase libido, potency, or sexual pleasure. This word is derived from ëAphroditaeí the Greek Goddess of love and these substances are derived from plants, animals or minerals and since time immemorial they have been the passion of man (Shah, 2002). A lot of natural substances have historically been known as aphrodisiacs in Africa and Europe, like yohimbine and the mandrake plant, as well as ground rhinoceros horn in the Chinese culture and “Spanish fly” which is actually toxic. (Adimoelja, 2000). Even in today's culture, there are certain foods that are used as aphrodisiacs, including strawberries and raw oysters. Chocolate, coffee, and honey are also believed to have aphrodisiac potential. The hunt for an effective aphrodisiac has been a constant pursuit throughout history. The role of various dopaminergic, adrenergic, and serotonergic agents has been intensively examined in both human and animal studies. Some of these drugs have been considered for their potential role for the treatment of sexual dysfunction, while some others have contributed to the basic neurophysiological processes in sexual arousal (Brock, 2002).
Infertility is defined as the inability of a couple to conceive after 12 months of unprotected regular sexual intercourse and it is estimated to affect 10%–15% of all couples. In almost half of such cases, a male factor is involved, but 15%–24% have unexplained etiology (Sikka, 2001). . Most of the infertile men are reported to have a low sperm concentration and decreased motility as the cause. Alterations in spermatogenesis event may result in the release of immature or abnormal spermatozoa in the ejaculate. Although the total sperm count may still be within the normal fertile range these individuals may turn infertile due to large fraction of unfit spermatozoa (Mahdi et al., 1999). Several conditions can interfere with spermatogenesis and reduce sperm quality and production. Many factors such as drug treatment, chemotherapy, toxins, air pollution, and insufficient vitamin intake may have harmful effects on spermatogenesis and the normal production of sperm (Mosher and Pratt, 1991). For a long time, female factors have been regarded as the primary causes of failure to conceive. However, in 20% of involuntarily childless couples, the predominant cause is male related, and in another 27%, anomalies in both partners contribute to childlessness (WHO 2000). Genital infections, endocrine disturbances and immunological factors have been regarded as the most common causes of male subfertility. However, genetic and other molecular causes have been identified as contributing explanatory factors to an increasing degree (Ferlin et al., 2007b).
1.1 BACKGROUND OF STUDY
The hunt for natural supplement from medicinal plants is being intensified mainly because of its fewer side effects. Various substances of animal and plant origin have been used in folk medicines of different cultures to energize, vitalize and improve sexual function, and physical performance in men, out of these very few have been identified pharmacologically. The gradual shift to herbal therapy with its attendant increasing acceptance, even among the elites, make the herbal practitioners lay claims to having the cure to a myriad of ailments, including male infertility, irrespective of the etiology of such diseases (Anthony et al., 2006). A large number of plants have been tested throughout the world for the possible fertility regulatory properties (Bhatia et. al.,2010). Some medicinal plants are extensively used as aphrodisiac to relieve sexual dysfunction, or as fertility enhancing agents. They provide a boost of nutritional value thereby improving sexual performance and libido (Yakubu et al, 2007; Sumalatha et al., 2010). Sexual dysfunction is more prevalent in males than in females and thus, it is conventional to focus more on male sexual difficulties (Guay et al., 2003). In males however, studies have shown that prevalence of sexual dysfunction is age related. Scientific exploration and standardization of potential crude drugs is an urgent need to revolutionize our drug sector and it is possible as Nigeria is blessed with many natural forests with huge number of medicinal plants. The practice of self-medication by an increasing number of patients, the incessant aggressive advertising of these herbal aphrodisiacs, the invasion of the medicinal market with uncontrolled dietary supplements and the absence of real directives amplifies the potential health hazards to the community.
1.2 STATEMENT OF PROBLEM
There is the need to look for alternative therapy that is cheap and readily available, Sphenocentrum jollyanum recorded the highest frequency usage of 16.33%, among the 25 species used for sexual impotence or aphrodisiac (Getrude, 2010), hence, the choice of Sphenocentrum jollyanum Pierre . Traditional uses of different part of Sphenocentrum jollyanum Pierre, locally known in Yoruba as Akerejupon, in treatment of various ailments in West Africa sub-region are common practice (Amidu et al., 2008; Moody et al., 2006). Its medicinal importance was first highlighted by Dalziel (Dalziel, 1955) in which it was noted that the leaves decoctions were used as vermifuge. It is reputed for use in dressing wounds particularly chronic wounds, feverish conditions, cough as well as being an aphrodisiac (Dalziel, 1955; Iwu, 1993).
Spheocentrum jollyanum roots are chewed raw or cut up into pieces and infused in gin for 3 days to be taken as “bitters”. This is perceived to strengthen the penis and cause the erection to be long-lasting. The root of Spheocentrum jollyanum is chewed as a central nervous system (CNS) stimulant and aphrodisiac (Abbiw, 1990; Irvine, 1961). Earlier studies have shown that methanolic extract of root of Spheocentrum jollyanum increased the testosterone levels in albino rats as well as a dose-dependent reduction in progressive motility of spermatozoa, viability and total sperm count (Raji et al., 2006). Furthermore, daily administration of the extract to rats for three weeks increased level of testosterone and FSH (Owiredu et al,2007). The leave (Mbaka et al., 2010),seed (Mbaka et al., 2010), and the root (Mbaka et al., 2010) of SJ have equally been shown to possess haematinic property which is essential for its aphrodisiac property. The plant (Akerejupon) has steroidogenic potential and this explains its use as an aphrodisiac agent but the intake needs to be regulated because the sphenocentrum jollyanum could produce harmful effects on male reproductive functions (Raji et al., 2006).
Though several studies have been carried out on sexual activities of the S. jollyanum root extracts, there is need to investigate the metabolic effect of the ethanolic extract of sphenocentrum jollyanum root as a fertility enhancing plant.
1.3 SIGNIFICANCE OF STUDY
It serves as a means of validating the folkloric use of the plant as a fertility enhancing plant. Thus complementing previous study to actually substantiate claims for its use.
1.4 OBJECTIVES OF STUDY
The overall objective of the present study is to scientifically evaluate the claimed fertility enhancing potential and to assess the metabolic effect of the ethanolic extract of Sphenocentrum jollyanum pierre (Menispermaceae) root using male wistar rats as model.
The specific objectives include the following
•To determine the proximate and phytochemical composition of the ethanolic extract of Sphenocentrum jollyanum (root) this will justify the ethno pharmacological use of the plant .
•To evaluate the acute toxicity of the plant part and change in organ to body weight index of the male rats after administration of the extract.
•To investigate the effect of the ethanolic extract of S. jollyanum root on semen and testicular morphology of male wistar rats . This will scientifically substantiate its efficacy and potency.
• To assess the hematological parameters after administration of the extract. This will give information blood relating function of the plant extract .
• To determine the effects of the plant extract on serum lipid profile, total protein and albumin.
•To investigate the duration (length of days) of optimal administration of the plant extract.
•To provide information on the mode of action of the plant acclaimed fertility enhancing potential.