RESUMO
Sperms are highly specialized cells for delivering DNA from male to the ovum. Incredibly, wide degree of diversity in sperm morphology in their basic structures i.e. head, middle piece and tail is found across species. Differences in terms of overall size of the sperm, shape and number of sperm produced are also incredible. One of the key for this variations or diversity in sperm may be associated with female reproductive tract, sperm competition, testicular size and sperm size and number. Establishing a correlation between sperm morphology and factors influencing them is a phenomenal task. In this mini-review these associations and the anatomical and functional adaptations among different from of sperm cells that have evolved to optimize fertilization success are discussed. Nevertheless, explaining these morphological diversities in sperm cells is a challenging question and it seems that evolutionary biologists have only recently engaged in exploring its links and patterns. From the literatures it seems that there is no causal relationship between sperm size and testicular size, however, the accumulated knowledge do indicates evolution of sperm morphology across species has some associations with female reproductive tract, sperm competition and sperm size and number, however interpreting these results for phylogentic correlations should be approached with caution.
RESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Mucuna pruriens Linn. (M. pruriens) is a leguminous plant that has been recognized as an herbal medicine for improving fertility and related disorders in the Indian traditional system of medicine, however without proper scientific validations. AIM OF THE STUDY: To study the effect of ethanolic seed extract of M. pruriens on mitochondrial dysfunction and the DNA damage in hyperglycemic rat epididymal spermatozoa. MATERIALS AND METHODS: Male Wistar albino rats were divided as control (Sham), diabetes induced [streptozotocin 60 mg/kg of body weight (b.w.) in 0.1M citrate buffer] (STZ), diabetic rats administered with 200mg/kg b.w. of extract (STZ+MP) and normal rats administered with 200mg/kg b.w. of extract (Sham+MP). M. pruriens was administered (gavage) once daily for a period of 60 days. On 60th day animals were sacrificed by cervical dislocation sperm were collected from epididymis and subjected various analysis like antioxidants, ROS, lipid peroxidation (LPO), DNA damage, chromosomal integrity and mitochondrial membrane potential (MMP). RESULTS: Significant reduction in the sperm count, motility, viability and significant increase in the number of abnormal sperm in STZ compared to sham was noticed. STZ rat sperm showed significant increase in LPO and DNA damage. Both the enzymic and non-enzymic were decreased; MMP and the mitochondrial functions were severely affected in STZ group. The diabetic rats supplemented with M. pruriens showed a remarkable recovery in antioxidant levels and reduced LPO with well preserved sperm DNA. MMP and mitochondrial function test were also preserved in STZ+MP rat sperm. CONCLUSION: The present study has clearly demonstrated the potency of M. pruriens to reduce the diabetic induced sperm damage induced by oxidative stress (OS). These observations are encouraging to perform similar studies in human.