Preliminary Study On The Effect Of DHA On Preadipocyte And Mitochondria Development In Grass Carp Ctenopharyngodon Idellus

The use of high-lipid diets and intensive farming in aquaculture has proven to lead toexcessive fat deposition in grass carp, which affected animal quality. Docosahexaenic acid(DHA) plays a very important regulatory role in adipocyte development, inhibiting lipidaccumulation. It is very crucial to clarify the mechanism of DHA in grass carp adipocytedevelopment. This work studied the effect of DHA on grass carp adipocyte in primarilydifferent development in vitro, including proliferation, differentiation, apoptosis andhydrolysis, providing insight into the molecular mechanism of energy metabolism in grasscarp.In this study, grass carp was used as experimental animal.The change of adipocyte andmitochondria development was detected during cell culture period. The main results were asfollows:1. The gene of Bcl-2, ATGL (Genbank accession number HQ845211), Bax (Genbankaccession number HQ845211), Caspase3(Genbank accession number JQ793789), Caspase9(Genbank accession number JQ793787), Nrf-1(Genbank accession number JF939202), CPT-1A (Genbank accession number JF728839), PCNA (Genbank accession number JX524136),TFAM (Genbank accession number JX855839) and CS (Genbank accession numberJQ713861) in grass carp were cloned. The obtain sequence length are1292bp,687bp,417bp,588bp,783bp,481bp,642bp,513bp,492bp and1035bp, respectively.2. The expression of Bcl-2mRNA and ATGL mRNA in ten tissues was investigated byreal time PCR. The results showed that Bcl-2gene and ATGL gene was widely expressed inten tissues of grass carp. The highest expression level of Bcl-2was observed in IPF, kidney,spermary and the lowest expression level were observed in muscle. The expression of othertissues was between IPF and muscle. The highest expression level of ATGL was observed inIPF and the higher expression level was observed in liver and muscle. The lower expressionwas observed in other tissues. 3. DHA promoted the preadipocytes of grass carp proliferation. Oil red O stainingsuggested DHA inhibited differentiation. DHA promoted cell apoptosis in short time, theninhibited cell apoptosis, which was consistent with LDH acitivity and expression ofapoptosis-related genes. DHA increased glycerol release, which was consistent withexpression of ATGL gene. The MDA content and SOD activity increased with DHAtreatment.4. DHA increaseded mitochondria mass, increased the DHA content in mitochondria,and no effect on membrane potential of mitochondria.In conclusion, our data suggested that DHA may decrease adipocyte mass, lipid contentand lipid deposition by inhibting adipocyte differentiation, promoting apoptosis, promotinghydrolysis and increasing mitochondira mass.