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Publications (4)3.62 Total impact

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    ABSTRACT: Triacylglycerol hydrolase (TGH) plays an important role in intracellular lipid metabolism. However, most previous studies on TGH were focused on rodent animals. Pig is considered as one of the best models for studying obesity, diabetes, and other lipid metabolism related diseases. So far, we do not know whether TGH is to play a role in lipolysis in porcine primary adipocyte through stimulation by hormones as Hormone-sensitive lipase (HSL). The objective of this study is to explore the mechanisms that regulate TGH expression in porcine adipocyte and its role in fasting-induced and Isoproterenol-stimulated lipolysis in porcine primary adipocytes. Stromal-vascular cells containing preadipocytes were isolated from cervical and dorsal subcutaneous adipose tissues of approximately 3-day-old Chinese male piglets. After confluence, the differentiation was induced by Insulin, hydrocortisone, and transferrin. The primary adipocytes were cultured in various concentration (0.1 to 200 micromol/l) Isoproterenol for 0-12 h or serum-free medium after differentiation. The glycerol release and triacylglycerol (TG) contents were detected when the cells were collected. Then, expression of TGH and HSL mRNA and their protein were determined by RT-PCR, Western Blot, and lipolytic analysis. Both TGH mRNA and protein were not detected on day 0, but as differentiation was induced, their expression displayed a great increase. The expression of TGH mRNA showed the highest level on day 4, but its protein reached the highest level on day 6 and began to fall down from day 8. The expression of TGH mRNA and proteins was increased in serum-free media, and mRNA expression was decreased while changed into complete media again. The glycerol release increased significantly when the cells were cultured with serum-free media. The lower concentration of Isoproterenol (0.1 and 1 micromol/l) did not affect the expression of TGH and HSL, but higher concentration (10, 100, and 200 micromol/l) could greatly up-regulate HSL expression but did not affect TGH level. Also, the higher concentration of Isoproterenol could increase the glycerol release and decrease TG content in dose-dependent manner. These results suggested that TGH expression is differentiation-dependent in porcine primary adipocytes and TGH plays a role in fasting-induced lipolysis not hormone-stimulated lipolysis.
    Molecular and Cellular Biochemistry 09/2008; 315(1-2):159-67. · 2.33 Impact Factor
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    ABSTRACT: The specific expression of TGH and HSL genes in different tissues of Bamei pig was investigated by RT-PCR and Western blot in this study. The result of RT-PCR showed that the expression of HSL could be detected in all these seven tissues examined, and which was higher expressed in fat, lower in heart, liver, lung, spleen and kidney. Expression of TGH gene could also be detected in seven tissues, and higher in liver and fat, lower in heart and kidney and lowest in spleen and lung. The result of Western blot showed that, HSL gene was highest expressed in epiploica fat and subcutaneous fat, higher in other tissues, but couldn' t be detected in kidney. Expression of TGH was detected in epiploica fat, subcutaneous fat, liver, lung and spleen, and highest in fat and liver, but it hadn't be found in heart and kidney. These results suggested that both HSL and TGH could be regulated by post-transcriptional, and their function was involved in different tissues.
    Sheng wu gong cheng xue bao = Chinese journal of biotechnology 10/2007; 23(5):831-5.
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    ABSTRACT: Human, rat, and mouse studies have demonstrated the existence of a population of adipose mesenchymal stem cells (AMSCs) that can undergo multilineage differentiation in vitro. Understanding the clinical potential of AMSCs may require their use in preclinical large-animal models such as pigs. Thus, the objectives of this study were to establish a protocol for the isolation of porcine AMSCs from adipose tissue and to examine their ex vivo differentiation potential to adipocytes and osteoblast. The porcine AMSCs from passage 4 were selected for differentiation analysis. The adipocytes were identified morphologically by staining with Oil Red O, and the adipogenic marker genes were examined by RT-PCR technique. Osteogenic lineage was documented by deposition of calcium stained with Alzarin Red S, visualization of alkaline phosphatase activity, and expression of marker gene. Our result indicates that porcine AMSCs have been successfully isolated and induced differentiation into adipocytes and osteoblasts. This study suggested that porcine AMSCs are also a valuable model system for the study on the mesenchymal lineages for basic research and tissue engineering.
    In Vitro Cellular & Developmental Biology - Animal 03/2007; 43(2):95-100. · 1.29 Impact Factor
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    ABSTRACT: To investigate the effects of Baicalein (BAI) on the proliferation and differentiation of pig preadipocytes, and elucidate its potential mechanism. Primary preadipocytes of pig were cultured in vitro. The morphologic changes of preadipocytes differentiation were observed by Oil Red O staining. Status of cell proliferation was detected by MTT assay. The degree of adipogenesis and differentiation were measured by Oil Red O staining extraction assay. The activity of fatty acid synthase (FAS) was detected by spectrophotometry. The mRNA expression of special peroxisome proliferation activated receptor-gamma2 gene (PPARgamma2) was detected by reverse transcriptase polymerase chain reaction (RT-PCR). When preadipocytes differentiated into adipocytes, the preadipocytes were changed from shuttle shape to oval or round, in which big and small lipid droplets were filled. The proliferation of preadipocytes was inhibited by the treatment of 160-640 micromol/L BAI (P < 0.05). The mRNA expression of PPARgamma2 and FAS activity and the differentiation of preadipocytes was repressed by 40-320 micromol/L BAI treatment (P < 0.05). It is concluded that the proliferation and differentiation of preadipocytes is inhibited by BAI in some degree. The effect of BAI on differentiation of preadipocytes may be resulted from inhibiting the mRNA expression of PPARgamma2 and reducing FAS activity.
    Sheng wu gong cheng xue bao = Chinese journal of biotechnology 12/2006; 22(6):1002-6.