Maurya Sangeeta, Krishna Amitabh, Lal Bechan, Singh Ajit
Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India.
Andrologia. 2022 Dec;54(11):e14579. doi: 10.1111/and.14579. Epub 2022 Sep 3.
Asprosin is an orexigenic adipokine that regulates appetite and glucose homeostasis in mammals. To date, only fragmentary findings are reported regarding its role in testicular activities. In the current investigation, immunolocalization and direct action of asprosin in adult mice testis was evaluated. Immunohistochemical and immunoblot studies were performed to analyse the testicular expression of asprosin. Intratesticular treatment of asprosin (0.1 μg and 1.0 μg per testis) was given to evaluate its direct action on testicular functions. Sertoli and Leydig cells were found to be immuno-positive for asprosin. Intratesticular administration of asprosin resulted into a significant increase in glucose and lactate levels along with enhanced expression of asprosin receptor OLFR734, insulin receptor (IR), glucose transporter 8 (GLUT 8), lactate dehydrogenase (LDH) activity and monocorboxylate transporters (MCT2 and 4). In addition, asprosin administration increased the testicular expression of cell proliferation (proliferating cell nuclear antigen: PCNA), cell survival (B cell lymphoma 2: Bcl2) and decreased germ cell apoptosis (Cysteine aspartic acid protease 3: Caspase 3) leading to increased sperm counts. Further, asprosin treatment resulted into increased level of total cholesterol, testosterone and steroidogenic markers (steroidogenic acute regulatory protein: StAR; 3beta-hydroxysteroid dehydrogenases: 3β HSD and 17beta-hydroxysteroid dehydrogenases: 17β HSD). Asprosin treatment promotes testicular glucose uptake and lactate synthesis to provide energy for steroidogenesis and spermatogenesis. The significant correlation between the asprosin-induced increased IR expression and increased testosterone, glucose and lactate levels suggests its role in increased survival and proliferation but decrease in germ cell apoptosis. This study proposed asprosin's role as an autocrine/paracrine regulator of testicular functions in adult mice.
Asprosin是一种促食欲的脂肪因子，可调节哺乳动物的食欲和葡萄糖稳态。迄今为止，关于其在睾丸活动中的作用仅有一些零散的研究结果报道。在本研究中，对成年小鼠睾丸中Asprosin的免疫定位和直接作用进行了评估。通过免疫组织化学和免疫印迹研究分析了睾丸中Asprosin的表达。给予睾丸内注射Asprosin（每只睾丸0.1μg和1.0μg）以评估其对睾丸功能的直接作用。发现支持细胞和间质细胞对Asprosin呈免疫阳性。睾丸内注射Asprosin导致葡萄糖和乳酸水平显著升高，同时Asprosin受体OLFR734、胰岛素受体（IR）、葡萄糖转运蛋白8（GLUT 8）、乳酸脱氢酶（LDH）活性以及单羧酸转运蛋白（MCT2和4）的表达增强。此外，注射Asprosin增加了睾丸中细胞增殖（增殖细胞核抗原：PCNA）、细胞存活（B细胞淋巴瘤2：Bcl2）的表达，并减少了生殖细胞凋亡（半胱天冬酶3：Caspase 3），从而导致精子数量增加。进一步研究发现，Asprosin处理导致总胆固醇、睾酮和类固醇生成标志物（类固醇生成急性调节蛋白：StAR；3β-羟基类固醇脱氢酶：3β HSD和17β-羟基类固醇脱氢酶：17β HSD）水平升高。Asprosin处理促进睾丸对葡萄糖的摄取和乳酸的合成，为类固醇生成和精子发生提供能量。Asprosin诱导的IR表达增加与睾酮、葡萄糖和乳酸水平升高之间的显著相关性表明，它在增加细胞存活和增殖但减少生殖细胞凋亡方面发挥作用。本研究提出Asprosin在成年小鼠睾丸功能中作为自分泌/旁分泌调节因子的作用。
