Animal Science and Technology College, Beijing University of Agriculture, Beijing, 102206, China.
Department of Livestock and Poultry Products Testing, Beijing General Station of Animal Husbandry, Beijing, 100107, China.
Theriogenology. 2024 Dec;230:220-232. doi: 10.1016/j.theriogenology.2024.09.026. Epub 2024 Sep 25.
Reproductive performance is a crucial aspect of poultry production and is carefully controlled by endocrine, paracrine, and autocrine factors. This study aimed to investigate the effect of lycopene on testosterone synthesis in Leydig cells of laying breeder roosters, clarify the mechanism of lycopene improving Leydig cells function and promoting testosterone production, and explore the role of related signal transduction pathways in testosterone synthesis.
A total of 96 healthy 55-week-old breeding roosters were randomly assigned to one of five dietary treatments. They were provided with a corn-soybean meal-based diet containing different levels of lycopene: 0 mg/kg (control), 50 mg/kg, 100 mg/kg, or 200 mg/kg. The experiment lasted for 6 weeks. With the increase in lycopene levels, the testosterone content in the plasma was significantly higher than in the control group. Testicular Leydig cells were isolated and cultured from fresh testicular tissue of 45-wk-old to 60-wk-old breeding roosters. Various doses of lycopene were administered to Leydig cells, and subsequently, cells were collected for the detection of cell viability and testosterone content. The optimal concentration of lycopene to be added was determined, and changes in mRNA expression and protein levels of key proteins involved in testosterone synthesis were investigated. The results showed that lycopene treatment significantly increased testosterone secretion, mRNA expression, and protein levels of steroid-producing enzymes. Cells were collected to measure the activity of antioxidant enzymes, the mRNA transcription level of apoptotic factors, and the protein expression of apoptotic factors after treatment with lycopene. The results showed that lycopene significantly increased the activities of antioxidant enzymes, and the ability to inhibit oxygen radicals, and decreased the content of malondialdehyde. Apoptosis was inhibited by regulating the expression of apoptosis-inducing and anti-apoptosis factors. After that, the MAPK signaling pathway and downstream SF-1, Nrf2 gene, and protein expression levels were detected. The results showed that lycopene treatment significantly increased the gene and protein expression of JNK, SF-1, and Nrf2, and significantly decreased the gene and protein expression of p38.
Lycopene treatment could promote testosterone synthesis of testicular Leydig cells by activating MAPK-SF-1 (increasing steroid-producing enzyme level) and MAPK-Nrf2 pathways (resisting oxidative damage).
生殖性能是家禽生产的一个关键方面，由内分泌、旁分泌和自分泌因素精细调控。本研究旨在探讨番茄红素对种公鸡睾丸间质细胞睾酮合成的影响，阐明番茄红素改善睾丸间质细胞功能和促进睾酮生成的作用机制，并探讨相关信号转导通路在睾酮合成中的作用。
将 96 只健康的 55 周龄种公鸡随机分为 5 个日粮处理组，每组 18 只，分别饲喂基础玉米-豆粕日粮和添加 0、50、100、200mg/kg 番茄红素的日粮，试验期 6 周。随着番茄红素水平的增加，血浆中睾酮含量显著高于对照组。从 45 周龄到 60 周龄的种公鸡新鲜睾丸组织中分离和培养睾丸间质细胞。用不同剂量的番茄红素处理 Leydig 细胞，然后收集细胞检测细胞活力和睾酮含量。确定最佳添加浓度，并检测参与睾酮合成的关键蛋白的 mRNA 表达和蛋白水平变化。结果表明，番茄红素处理显著增加了睾酮的分泌、mRNA 表达和蛋白水平。收集细胞后，检测抗氧化酶的活性、凋亡因子的 mRNA 转录水平和凋亡因子的蛋白表达。结果表明，番茄红素显著提高了抗氧化酶的活性和清除氧自由基的能力，降低了丙二醛的含量。通过调节凋亡诱导和抗凋亡因子的表达来抑制凋亡。然后，检测 MAPK 信号通路和下游 SF-1、Nrf2 基因和蛋白表达水平。结果表明，番茄红素处理显著增加了 JNK、SF-1 和 Nrf2 的基因和蛋白表达，显著降低了 p38 的基因和蛋白表达。
番茄红素处理可通过激活 MAPK-SF-1（增加类固醇生成酶水平）和 MAPK-Nrf2 途径（抵抗氧化损伤）促进睾丸间质细胞的睾酮合成。
