Nandi S, Tripathi S K, Gupta P S P, Mondal S
ICAR-National Institute of Animal Nutrition and Physiology, Bangalore 560030, India.
ICAR-National Institute of Animal Nutrition and Physiology, Bangalore 560030, India.
Theriogenology. 2017 Dec;104:80-86. doi: 10.1016/j.theriogenology.2017.07.024. Epub 2017 Jul 27.
The present study was undertaken to study the effect of metabolic stressors like elevated levels of ammonia, urea, Non-esterified fatty acid (NEFA) and β-hydroxybutyric acid (BHB) on preantral follicle growth, survival, growth rates of oocytes enclosed in preantral follicles (PFs), maturation rates of oocytes recovered from cultured follicles, hormone production (estrogen and progesterone), reactive oxygen species (ROS) as well as superoxide dismutase (SOD) activity. Small pre-antral follicles (SPFs, 100-250 μm) and large pre-antral follicles (LPFs, 250-450 μm) were isolated from slaughterhouse ovaries by a mechanical cum enzymatic method. SPFs and LPFs were cultured in vitro for 14 and 7 days respectively and examined for their growth, survival and growth rates of enclosed oocytes in PFs exposed with different concentration of ammonia (0, 100, 150, 200, 250, 300 and 400 μM), urea (0, 4, 4.5, 5, 5.5,6, 7 and 8 mM), NEFA [Basal NEFA (70 μM): stearic acid, SA (10 μM)+Palmitic acid, PA(20 μM)+oleic acid, OA(40 μM), b) Medium combo (140 μM): SA (20 μM)+ PA(40 μM)+ OA(80 μM), c) High combo (210 μM): SA (30 μM)+PA(60 μM)+OA(120 μM), d) Very high Combo (280 μM): SA(40 μM)+PA(80 μM)+OA(160 μM)] and BHB (0, 0.5, 0.75, and 1 μM). Results indicated that ammonia, urea, NEFA and BHB caused inhibition of survival and growth of in vitro cultured ovine PFs and enclosed oocytes at the levels of 300 μM, 8 mM, high combo level of NEFA and 0.75 μM respectively. Our study may contribute to the identification of the mechanisms involved in decline of fertility due to metabolic and nutritional stress in ruminants.
本研究旨在探讨氨、尿素、非酯化脂肪酸（NEFA）和β-羟基丁酸（BHB）等代谢应激源对窦前卵泡生长、存活、窦前卵泡（PFs）中卵母细胞的生长速率、培养卵泡中回收的卵母细胞的成熟率、激素分泌（雌激素和孕酮）、活性氧（ROS）以及超氧化物歧化酶（SOD）活性的影响。通过机械结合酶法从屠宰场的卵巢中分离出小窦前卵泡（SPFs，100 - 250μm）和大窦前卵泡（LPFs，250 - 450μm）。将SPFs和LPFs分别在体外培养14天和7天，并检测其在暴露于不同浓度的氨（0、100、150、200、250、300和400μM）、尿素（0、4、4.5、5、5.5、6、7和8 mM）、NEFA [基础NEFA（70μM）：硬脂酸，SA（10μM）+棕榈酸，PA（20μM）+油酸，OA（40μM），b）中等组合（140μM）：SA（20μM）+ PA（40μM）+ OA（80μM），c）高组合（210μM）：SA（30μM）+PA（60μM）+OA（120μM），d）非常高组合（280μM）：SA（40μM）+PA（80μM）+OA（160μM）]和BHB（0、0.5、0.75和1μM）条件下的生长、存活及其中卵母细胞的生长速率。结果表明，氨、尿素、NEFA和BHB分别在300μM、8 mM、NEFA高组合水平和0.75μM时，会抑制体外培养的绵羊PFs及其内部卵母细胞的存活和生长。我们的研究可能有助于确定反刍动物因代谢和营养应激导致生育力下降所涉及的机制。
