Health Sciences Research Centre, Faculty of Health Sciences, University of Beira Interior (CICS-UBI), 6201-506 Covilhã, Portugal.
Nat Rev Urol. 2012 May 1;9(6):330-8. doi: 10.1038/nrurol.2012.77.
Male factor infertility is increasing in developed countries, and several factors linked to lifestyle have been shown to negatively affect spermatogenesis. Sertoli cells are pivotal to spermatogenesis, providing nutritional support to germ cells throughout their development. Sertoli cells display atypical features in their cellular metabolism; they can metabolize various substrates, preferentially glucose, the majority of which is converted to lactate and not oxidized via the tricarboxylic acid cycle. Why Sertoli cells preferentially export lactate for germ cells is not entirely understood. However, lactate is utilized as the main energy substrate by developing germ cells and has an antiapoptotic effect on these cells. Several biochemical mechanisms contribute to the modulation of lactate secretion by Sertoli cells. These include the transport of glucose through the plasma membrane, mediated by glucose transporters; the interconversion of pyruvate to lactate by lactate dehydrogenase; and the release of lactate mediated by monocarboxylate transporters. Several factors that modulate Sertoli cell metabolism have been identified, including sex steroid hormones, which are crucial for maintenance of energy homeostasis, influencing the metabolic balance of the whole body. In fact, energy status is essential for normal reproductive function, since the reproductive axis has the capacity to respond to metabolic cues.
男性因素不孕在发达国家呈上升趋势，一些与生活方式相关的因素已被证明会对精子发生产生负面影响。支持细胞对于精子发生至关重要，为发育中的生殖细胞提供营养支持。支持细胞在细胞代谢中表现出非典型特征；它们可以代谢各种底物，优先是葡萄糖，其中大部分转化为乳酸而不是通过三羧酸循环氧化。为什么支持细胞优先将乳酸输出给生殖细胞还不完全清楚。然而，乳酸被发育中的生殖细胞用作主要能量底物，并对这些细胞具有抗凋亡作用。几种生化机制有助于调节支持细胞的乳酸分泌。这些包括葡萄糖通过葡萄糖转运蛋白穿过质膜的转运；丙酮酸通过乳酸脱氢酶转化为乳酸；以及通过单羧酸转运蛋白介导的乳酸释放。已经确定了几种调节支持细胞代谢的因素，包括性激素，它们对于维持能量稳态至关重要，影响全身的代谢平衡。事实上，能量状态对于正常的生殖功能是必不可少的，因为生殖轴有能力对代谢线索做出反应。
