Protein profile as a quality indicator of cryopreserved semen from Tambaqui Colossoma macropomum (Cuvier, 1818)

Abstract The aim of this study was to evaluate the association between proteins in the seminal plasma of tambaqui Colossoma macropomum (Cuvier, 1818) with seminal quality indicators after thawing. The semen was cryopreserved with a dilution based on BTS with 8% DMSO. A 200 µL sample of semen from each animal was diluted in 800 µL BTS, centrifuged at 800 rpm, and the supernatant was cryopreserved to further analyze of the protein profile of seminal plasma through one-dimensional electrophoresis (SDS-PAGE). After 15 days of cryopreservation, a cryopreserved semen straw was thawed to analyze both qualitative and quantitative parameters. When considering all collections, the SDS-PAGE identified 15 protein bands in the seminal plasma of tambaqui. When the interaction (presence or absence) between proteins observed in the seminal plasma and the post thawed spermatic parameters was evaluated, we observed a great influence of the presence of proteins on spermatic quality. A greater (P<0.05) fertilization rate was observed with the presence of proteins 12, 34, 44, 85, and 90 kDa. Proteins in seminal plasma of tambaqui influenced the spermatic quality after thawing, and thus, they can be utilized as an indicator of sperm quality, especially the proteins with a molecular weight ≤ 50 kDa.

摘要 本研究旨在评估巨脂鲤（tambaqui，学名Colossoma macropomum，Cuvier, 1818）精浆中的蛋白质与解冻后精液品质指标之间的关联。实验采用添加8% 二甲基亚砜（DMSO）的BTS稀释液对精液进行冷冻保存。采集每尾鱼的200 µL精液样本，用800 µL BTS进行稀释，随后以800 rpm离心，取上清液冷冻保存，后续通过一维电泳（SDS-PAGE）分析精浆的蛋白质谱。冷冻保存15天后，解冻一根冷冻精液细管以分析其定性与定量参数。综合所有采集样本的分析结果，SDS-PAGE在巨脂鲤精浆中检出15条蛋白条带。当分析精浆中蛋白的存在与否与解冻后精子参数之间的关联时，本研究发现蛋白的存在对精子品质具有显著影响。当存在12、34、44、85及90千道尔顿（kDa）的蛋白时，受精率显著更高（P<0.05）。巨脂鲤精浆中的蛋白可影响解冻后的精子品质，因此可作为精子品质的评价指标，尤其是分子量≤50 kDa的蛋白。