AUTHOR=Guo Huixing , Wang Mangmang , Wang Xi , Xiao Kang , Huang Yangyang , Hua Haokun , Xiong Wei , Liu Wenbin , Abasubong Kenneth Prudence , Qiang Wei , Chi Cheng , Jiang Guangzhen 

TITLE=Effect of dietary cholesterol on ovarian development of Chinese mitten crabs (Eriocheir sinensis)

JOURNAL=Frontiers in Marine Science

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.1070829

DOI=10.3389/fmars.2022.1070829

ISSN=2296-7745

ABSTRACT=<p>This study was conducted to evaluate the effect of cholesterol (CHO) on ovarian development of <italic>Eriocheir sinensis</italic> through a feeding trial. Crabs (average weight 43.35 ± 0.05 g) were randomly fed with one of three diets: 0% CHO, 0.4% CHO and 1.6% CHO for 16 weeks. Results indicated that the hepatosomatic index (HSI) and gonad index (GSI) of crabs fed with 0.4% CHO diet were significantly higher than those in the control group. (<italic>P</italic> &lt; 0.05). Meanwhile, 0.4% CHO can significantly increase the gene expression of <italic>vtg</italic> and <italic>vgr</italic> in ovary (<italic>P</italic> &lt; 0.05), thus promoting the accumulation of Vtg. The protein expression of MEK1/2, ERK, p-ERK1/2, Cyclin B and CDC2 were significantly increased in the 0.4% CHO group, therefore dietary CHO might promote oocyte maturation by activating MAPK signal pathway and cooperating with maturation promoting factor (MPF). Further exploration results showed that 0.4% CHO was able to significantly up-regulate the protein expression of STAR and SR-B1 to promote the transport of CHO to ovary, thereby providing sufficient substrates for estradiol (E<sub>2</sub>) synthesis. In addition, the results <italic>in vivo</italic> and <italic>in vitro</italic> shown that CHO could regulate the activities of enzymes such as CYP11A1 and CYP19A1 through the cAMP-PKA-CREB/SF-1 signal pathway and then affects the level of E<sub>2</sub> in the organism. In summary, supplementing the appropriate amount of CHO in the diet can improve the E<sub>2</sub> level of the organism, thus increasing the accumulation of nutrients in the ovary, promoting the completion of meiosis, and finally achieving the purpose of promoting ovarian maturation.</p>