C/EBPb converts bovine fibroblasts to adipocytes without hormone cocktail induction

BACKGROUND: Adipogenesis and fibrogenesis can be considered as a competitive process in muscle, which may affect the intramuscular fat deposition. The CCAAT/enhancer-binding protein beta (C/EBPb) plays an important role in adipogenesis, which is well-characterized in mice, but little known in bovine so far. RESULTS: In this study, real-time qPCR revealed that the level of C/EBPb was increased during the developmental stages of bovine and adipogenesis process of preadipocytes. Overexpression of C/EBPb promoted bovine fibroblast proliferation through mitotic clonal expansion (MCE), a necessary process for initiating adipogenesis, by significantly downregulating levels of p21 and p27 (p < 0.01). Also, the PPARc expression was inhibited during the MCE stage (p < 0.01). 31.28% of transfected fibroblasts adopted lipid-laden adipocyte morphology after 8 d. Real-time qPCR showed that C/EBPb activated the transcription of early stage adipogenesis markers C/EBPa and PPARc. Expression of ACCa, FASN, FABP4 and LPL was also significantly upregulated, while the expression of LEPR was weakened. CONCLUSIONS: It was concluded C/EBPb can convert bovine fibroblasts into adipocytes without hormone induction by initiating the MCE process and promoting adipogenic genes expression, which may provide new insights into the potential functions of C/EBPb in regulating intramuscular fat deposition in beef cattle.

Identification of genetic variants the CCKAR gene and based on body measurement and carcass quality characteristics in Qinchuan beef cattle (Bos taurus)

BACKGROUND: This study aimed to explore genetic polymorphisms of the CCKAR gene and their relationship with the growth and development of Qinchuan cattle which could be used as molecular markers for the improvement of the breeding of Qinchuan cattle. RESULTS: Here, we have identified seven single nucleotide polymorphisms (SNPs) at loci g. 1463 C>G; g. 1532 T>A; g. 1570 G>A; g. 1594 C>A; g. 1640 T>C; g. 1677 G>C; and g. 1735 C>T in the coding region of the bovine CCKAR gene. The frequencies identified on allelic and genotypic characteristics have shown that all seven SNPs diverged from the Hardy-Weinberg-Equilibrium. The SNP2, SNP3, SNP6 and SNP7 had the lowest polymorphism information content values, and remaining SNPs were found to be moderate (0.25 < PIC < 0.50). The genotype CG in SNP1 at loci g.1463 C>G had the greatest association with WH, HW, CD and CCF, while the genotype TA at the very same loci was associated with BFT, ULA and IMF content in Qinchuan cattle. The CCKAR gene expression level in adipose tissue, small intestine, liver and skeleton muscle was found to be higher, whereas, the expression level of mRNA in organs of other digestive system including reticulum, abomasum and omasum was moderate. Some expression of CCKAR mRNA was found in the large intestine, kidney and rumen. CONCLUSIONS: In summary, our finding suggested that the CCKAR gene could be used as a potential candidate for the improvement of carcass quality and body measurements of Qinchuan cattle.

Transcriptome profiling reveals differential expression of genes potentially involved in muscle and adipose tissue development of cattle

BACKGROUND: To identify differentially expressed genes (DEGs) between muscle and adipose in cattle, we analyzed the data from the RNA sequencing of three Angus×Qinchuan crossbred cattle. RESULTS: Searched the Gene Expression Omnibus (GEO) for a microarray dataset of Yan yellow cattle, GSE49992. After the DEGs were identified, we used STRING and Cytoscape to construct a protein­protein interaction (PPI) network, subsequently analyzing the major modules of key genes. In total, 340 DEGs were discovered, including 21 hub genes, which were mainly enriched in muscle contraction, skeletal muscle contraction, troponin complex, lipid particle, Z disc, tropomyosin binding, and actin filament binding. CONCLUSIONS: In summary, these genes can be regarded as candidate biomarkers for the regulation of muscle and adipose development.

Cichoric acid from extracted Echinacea purpurea induces the proliferation and apoptosis of peripheral blood mononuclear cells from yaks

BACKGROUND: Cichoric acid (CA) is extracted from Echinacea purpurea. It is well known and widely used for its immunological function. However, the effect of CA on peripheral blood mononuclear cells (PBMCs) from yaks is still unclear. This study investigated the potential influences of CA on the proliferation, cytokine induction, and apoptosis of PBMCs from Datong yak in vivo, and aimed to provide a basis for exploring the pharmacological activities of CA on yaks. RESULTS: In this study, CA promoted PBMCs proliferation by combining concanavalin A (Con A) and exhibited a dose-dependent effect as demonstrated by a Cell Counting Kit-8. The concentration of 60 µg/ml CA was the best and promoted the transformation from the G0/G1 phase to the S and G2/M phases with Con A. Furthermore, 60 µg/ml CA significantly increased IL-2, IL-6, and IFN-γ levels and PCNA, CDK4 and Bcl-2 expression levels, but it significantly inhibited the TP53, Bax, and Caspase-3 expression levels. Transcriptome analysis revealed a total of 6807 differentially expressed genes (DEGs) between the CA treatment and control groups. Of these genes, 3788 were significantly upregulated and 3019 were downregulated. Gene Ontology and pathway analysis revealed that DEGs were enriched in cell proliferation and immune function signaling pathways. The expression level of some transcription factors (BTB, Ras, RRM_1, and zf-C2H2) and genes (CCNF, CCND1, and CDK4) related to PBMCs proliferation in yaks were significantly promoted after CA treatment. By contrast, anti-proliferation-associated genes (TP53 and CDKN1A) were inhibited. CONCLUSIONS: In summary, CA could regulate the immune function of yaks by promoting proliferation and inhibiting inflammation and apoptosis of PBMCs.