Caspases and Spermatogenesis

During spermatogenesis, the number and quality of germ cells are balanced via apoptosis. In adults, close to 75% of spermatogonia and to lesser extent spermatocyte and spermatid are lost [17, 18]. It has been shown that germ cell apoptosis at the cellular level is controlled by endocrinal and local factors and at the intracellular level by p53 and caspases [19, 20]. Although procaspase-3, -6, and -7 and also the IAP caspase inhibitor have been found in normal histology of testis, activated forms of caspase-3, -6, and -7 were not found in normal testis using western blotting or immunohistochemistry methods. Procaspase-3 expression has been shown in testes with normal spermatogenesis and also in testis with sperm maturation arrest or ser-toli cell only (SCO). Kim et al. [21] found a diffuse signal for activated caspase-3 in sertoli and germ cell and also leydig cell in testes with sperm maturation arrest; however, the expression of activated caspase-3 has never been seen in testes with normal spermatogenesis [22]. Research suggests that spermatogenic arrest could be related to increased apoptotic rate in testes and increase of activated caspase-3 [22]. In contrast, varicocele patient [23] and hypospermatogenesis and SCO are associated with low level of apoptosis [24]. In the testes, the expression of CD95 and its receptor, which have been introduced as key regulators for germ cell apoptosis [25, 26], is localized to the germ and Sertoli cells [27]. The downstream factors of CD95 activation include various caspases, among which the caspase-8 has the most significant role [28].

Pregnancy Guide

Pregnancy Guide

A Beginner's Guide to Healthy Pregnancy. If you suspect, or know, that you are pregnant, we ho pe you have already visited your doctor. Presuming that you have confirmed your suspicions and that this is your first child, or that you wish to take better care of yourself d uring pregnancy than you did during your other pregnancies; you have come to the right place.

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