The Study On The Role Of Adipokine Chemerin In The Porcine Gonadal Function And Its Mechanism

The adipokine which named Chemerin play a physiological effects role in inflammatory response,glycemic and lipid metabolism,cardiovascular function and so on.At the same time,Chemerin may bear a part in reproductive function of animals.The study is aim to research into the role of adipokine which named Chemerin and its receptor in the porcine gonadal function and its mechanism by studying the expression and distribution of Chemerin and its receptors in porcine and mouse reproductive system,determine whether Chemerin and its receptor affect the endocrine function of porcine granulosa cellst,and the role of Chemerin in the maturation and development of porcine oocytes.The results are as follows.1.The Expression and distribution of Chemerin and its receptors in porcine and mouse reproductive system: The results that get from immunohistochemistry,immunofluorescence and Q-PCR show that Chemerin and its receptors are expressed similarly in ovarian granulosa cells,oocytes,corpus luteum and primordial follicles,uterine endothelial cells and oviduct epithelial cells,and GPR1 expression is significantly higher than the other two receptors CMKLR1 and CCRL2 in granulosa cells,cumulus,corpus luteum and stroma(P<0.001).2.Determine whether Chemerin and its receptor affect the endocrine function of porcine granulosa cellst were in vitro cultured: By grouping treatment of Chemerin recombinant protein,hCG and GPR1 antibody.The results showed that hCG could promote the secretion of progesterone and estrogen in porcine granulosa cells,while Chemerin could inhibit the secretion.After GPR1 antibody blocked the Chemerin/GPR1 signal pathway,the inhibition of progesterone was relieved,and the expression of steroidogenesis enzymes StAR,17?-HSD and CYP11A1 were significantly increased.This indicates that Chemerin may inhibit the expression of StAR,17?-HSD and CYP11A1 mainly by binding to receptor GPR1,thus inhibiting the synthesis and secretion of progesterone and estrogen.3.The role of Chemerin in the maturation and development of porcine oocytes,naked eggs and cumulus oocyte complexes were cultured in the medium with or without Chemerin recombinant protein respectively.We found that the maturation rate of naked eggs was extremely low in the in vitro culture process,and the difference was extremely significant compared with the in vitro maturation rate of cumulus oocyte complexes(P<0.001).However,after the addition of Chemerin recombinant protein,the meiosis process of porcine oocytes was inhibited,the maturation was delayed,and the maturation rate also decreased.However,when mature oocytes were cultured in the medium containing Chemerin recombinant protein,the cleavage rate of mature oocytes after adding Chemerin recombinant protein was significantly decreased compared with control group(P<0.001).In addition,we also found that oocytes that undergo parthenogenetic activation after naked eggs are cultured to maturity are prone to aneuploidy fission in later culture,or have already died or stagnated growth by the time of sample collection.Through the above research,we found that Chemerin and its receptor have similar expressions in granulosa cells,oocytes,corpus luteum,primordial follicles and uterine endothelial cells,oviduct epithelial cells in porcine and female mouse ovaries.The expression of receptor GPR1 is the highest.Chemerin may inhibit the expression of StAR,17?-HSD and CYP11A1 by binding to receptor GPR1,thus inhibiting the secretion of progesterone and estrogen by porcine granulosa cells.At the same time,Chemerin may also has an inhibitory effect on the maturation and development of porcine oocytes.