Tiwari Ashutosh, Singh Dheer, Kumar O Suneel, Sharma M K
Molecular Endocrinology Lab., Division of Animal Biochemistry, National Dairy Research Institute, Karnal 132001, Haryana, India.
Domest Anim Endocrinol. 2008 Apr;34(3):238-49. doi: 10.1016/j.domaniend.2007.07.003. Epub 2007 Aug 20.
The cytochrome P450 aromatase (aromP450) deficient mice are infertile due to an impairment of spermatogenesis associated with a decrease in sperm motility and inability to fertilize oocytes. The sperm analysis showed decreased sperm motility in humans, having Cyp19 gene mutations. Further, in human, it was hypothesized that aromatase could be used as marker of sperm quality, particularly in the acquisition of its motility. However, there is no information regarding the expression of aromP450 in spermatozoa of farm animals including cattle and buffalo. In the present study, the expression of aromP450 in ejaculated buffalo spermatozoa and its relationship with sperm motility of ejaculated spermatozoa was studied by RT-PCR using total RNA isolated from buffalo-ejaculated spermatozoa. The results showed that conventional RT-PCR could not amplify aromatase transcript, while a nested PCR detected the presence of P450arom mRNA in buffalo-ejaculated spermatozoa. RT reaction followed by nested PCR was performed to compare the expression of aromatase transcripts in buffalo-ejaculated spermatozoa of two category semen graded on the basis of mass motility and motile and non-motile spermatozoa separated by swim-up. A higher (P<0.01) expression of aromP450 transcript was found in spermatozoa obtained from the good quality semen (higher mass motility) to that in spermatozoa of poor quality semen (low mass motility). Similarly, higher (P<0.01) expression of aromP450 mRNA was observed in the motile spermatozoa as compared to non-motile spermatozoa separated from good quality semen by swim-up. It is concluded that the present study demonstrates a positive relation between aromatase transcript and mass motility of buffalo-ejaculated spermatozoa, which could be a putative marker for the quality of semen in farm animals, particularly the acquisition of sperm motility.
细胞色素P450芳香化酶（aromP450）缺陷小鼠不育，原因是精子发生受损，伴有精子活力下降以及无法使卵母细胞受精。精子分析显示，携带Cyp19基因突变的人类精子活力降低。此外，在人类中，有人推测芳香化酶可作为精子质量的标志物，尤其是在精子活力方面。然而，关于包括牛和水牛在内的家畜精子中aromP450的表达情况尚无相关信息。在本研究中，利用从水牛射出精子中分离的总RNA，通过逆转录聚合酶链反应（RT-PCR）研究了aromP450在水牛射出精子中的表达及其与射出精子活力的关系。结果表明，常规RT-PCR无法扩增出芳香化酶转录本，而巢式PCR检测到水牛射出精子中存在P450arom mRNA。进行逆转录反应后再进行巢式PCR，以比较基于总体活力分级的两类精液以及通过上浮法分离的活动精子和不活动精子中芳香化酶转录本在水牛射出精子中的表达情况。结果发现，从优质精液（总体活力较高）获得的精子中aromP450转录本的表达高于劣质精液（总体活力较低）中的精子。同样，与通过上浮法从优质精液中分离出的不活动精子相比，活动精子中aromP450 mRNA的表达更高（P<0.01）。研究得出结论，本研究证明了芳香化酶转录本与水牛射出精子的总体活力之间存在正相关关系，这可能是家畜精液质量的一个推定标志物，尤其是在精子活力方面。
