The Effect Of High-fat Diet And Exercise On KISS-1/GPR54 Expression In Testis Of Growing Rats

Objective:To investigate the effects of high-fat diet and exercise on the expression of KISS-1/GPR54 in testicular tissue of growing period rats.Methods:128 three-week-old weaned rats underwent high-fat diet and exercise（60⁷0%VO₂max,1h/day,5 days/week）intervention,and were randomly divided into standard diet group（group C）and standard exercise group（CE group）,high-fat diet group（HC group）,high-fat exercise group（HE group）.According to the former research,sample time points set on the PND21^stt day（21D,early childhood）,PND 35^thh day（35D,pre-puberty）,PND 43^rd day（43D,puberty）,PND 56^thh day（56D,maturity）.The testicular tissue testosterone concentration,the location of KISS-1 and GPR54 in testis tissue and the mRNA and protein content of KISS-1 and GPR54 in testis were detected by enzyme-linked immunosorbent assay,immunohistochemistry,Quantitative Real-time PCR and Western blotting.Results:（1）KISS-1 was expressed in both spermatogenic cells and Leydig cells of rat testis;GPR54 first appeared in spermatogenic cells,and then appeared in Leydig cells.The protein content of KISS-1 and GPR54 in testis tissue increased gradually during growing period,and KISS-1 protein increased rapidly from puberty to maturity;GPR54 protein increased rapidly from pre-puberty to adolescence.The expression level of KISS-1 mRNA was firstly increased and peaked at 35D.The expression level of GPR54 mRNA increased first and then decreased,and peaked at43D.（2）High-fat diet can affect the expression of KISS-1/GPR54 system in rat testis and reduce the expression level of KISS-1 protein.（3）60⁷0%VO₂max exercise intervention has no obvious effect on KISS-1/GPR54 expression localization in testis,and increases the KISS-1/GPR54 expression level in testis from pre-puberty to puberty.The exercise intervention can improve testicular development in rats with high fat diet.Conclusions:（1）KISS-1/GPR54 system is expressed in spermatogenic cells and Leydig cells of rat testis during early childhood（21D）,prepubertal（35D）,puberty（43D）,maturity（56D）.From early childhood to maturity,the expression of KISS-1/GPR54 system increased and peaked at maturity（56D）;KISS-1/GPR54system may be involved in promoting sperm maturation and regulation of sex hormone secretion during prepuberty.（2）High-fat diet can inhibit the testicular development of male rats in the growth phase,and can also down-regulate the protein and gene expression levels of KISS-1/GPR54 system in testis tissue,and change the expression of KISS-1/GPR54 system,and its role needs further study.（3）60⁷0%VO₂max moderate-intensity aerobic exercise will down-regulate the expression level of testis tissue KISS-1/GPR54;change the inhibitory effect of high-fat diet on testicular development in male rats,and up-regulate KISS-1/GPR54 in prepubertal stage and whether KISS-1/GPR54 in testicular tissue participates in its regulation remains to be further study.