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ABSTRACT: Excessive energy intake greatly contributes to the development of nonalcoholic fatty liver disease (NAFLD) in modern society. To better understand the comprehensive mechanisms of NAFLD development, we investigated the metabolic alterations of rats with NAFLD induced by high-fat diet (HFD). Male Wistar rats were fed a HFD or standard chow for control. After 16 weeks, rat serum was collected for biochemical measurement. The rats' livers were resected and subjected to histology inspection and gene expression analysis with complementary DNA microarray and metabolic analysis with gas chromatography-mass spectroscopy. In HFD rats, the serum cholesterol, triglycerides, glucose, and insulin contents were increased; and the total cholesterol and triglycerides in the livers were also significantly increased. Complementary DNA microarray analysis revealed that 130 genes were regulated by HFD. Together with real-time reverse transcriptase polymerase chain reaction, lipid metabolism regulatory members like sterol regulatory element binding factor 1 and stearoyl-coenzyme A desaturase 1 had up-regulation, whereas others like peroxisome proliferator-activated receptor, carnitine palmitoyltransferase 1, and 3-hydroxy-3-methylglutaryl-coenzyme A reductase had repressed expression, in HFD rat livers. Metabolomic analysis showed that tetradecanoic acid, hexadecanoic acid, and oleic acid had elevation and arachidonic acid and eicosapentaenoic acid had decreased content in HFD rat livers. Amino acids including glycine, alanine, aspartic acid, glutamic acid, and proline contents were decreased. The integrative results from transcriptomic and metabolomic studies revealed that, in HFD rat livers, fatty acid utilization through beta-oxidation was inhibited and lipogenesis was enhanced. These observations facilitated our understanding of the pathways involved in the development of NAFLD induced by HFD.
Metabolism: clinical and experimental 11/2009; 59(4):554-60. · 2.59 Impact Factor
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ABSTRACT: Leaf extract of Ginkgo biloba (GBE) is increasingly used as a herbal medicine for the treatment of neurodegenerative, cardiovascular and cerebrovascular diseases. Several studies have demonstrated many protective effects of GBE in neurons, the endothelium and liver. In this study, we investigated the molecular mechanisms underlying the effects of GBE in disorders induced by long-term exposure to a high-fat diet (HFD). Rats were fed an HFD with or without the GBE product GBE50 for 19 weeks. We found that GBE50 reduced the development of fatty liver induced by an HFD and inhibited the commonly observed elevation of serum cholesterol and lactate dehydrogenase levels. Transcriptome profiling analysis showed that several genes were modulated by GBE50 in liver, including those involved in lipid metabolism, carbohydrate metabolism, vascular constriction, ion transportation, neuronal systems and drug metabolism. Notably, a number of genes coding for proteins involved in cholesterol metabolism were repressed, and some were upregulated. Fatty acid biosynthesis appeared to be repressed, whereas fatty acid metabolism appeared to be enhanced. In conclusion, using transcriptome profiling analysis, we demonstrated the molecular basis for the pleiotropic effects of GBE50, particularly those involved in lipid metabolism. This study provided new clues for further pharmacological study of GBEs.
FEBS Journal 02/2009; 276(5):1450-8. · 3.79 Impact Factor
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Houkai Li,
Zuoquan Xie,
Jingchao Lin,
Huaiguang Song,
Qi Wang,
Ke Wang,
Mingming Su,
Yunping Qiu,
Tie Zhao,
Kai Song,
Xiaoyan Wang,
Mingmei Zhou,
Ping Liu,
Guoping Zhao, Qinghua Zhang,
Wei Jia
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ABSTRACT: Rodents respond to chronic high fat diet in at least two ways: some of them may readily gain body weight and become obese (termed obesity-prone, OP), and others may not (termed obesity-resistant, OR). Transcriptomic and metabonomic profiling of OP and OR rats has been conducted, showing two sets of significantly different phenotypic profiles in response to 16 weeks of high fat diet. We observed significant differences in transcriptional expression of nearly 80 genes, some of which are known to be involved in lipid metabolism, transport, and ketone body production. The different metabolic profiles in liver tissue extracts, serum, and urine between the two phenotypes can be ascribed to the corresponding pathways identified with multivariate statistical analysis, including fatty acid metabolism, Krebs cycle, and amino acid metabolism. The integration of results from transcriptomic and metabonomic studies revealed that the altered metabolic pathways in OP rats may involve the increased activity of sympathetic nervous system and Krebs cycle, an increased production of ketone bodies, and an adaptive regulatory process to store excessive lipids in liver through reverse cholesterol transport process. These biochemical variations at transcriptional and metabolic levels as a result of dietary intervention highlight the significance of combined "omics" strategy in the mechanistic study of obesity and metabolic disorders.
Journal of Proteome Research 11/2008; 7(11):4775-83. · 5.11 Impact Factor
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ABSTRACT: The cDNA of a Schistosoma japonicum myophilin-like protein was cloned, sequenced, and expressed in Escherichia coli as a recombined protein (rSj myophilin-like protein), and the protein was purified by affinity chromatography. The deduced amino acid sequences of the Sj myophilin-like protein showed significant homology to myophilin, calponin, Np22 and Mp20. Northern blot and RT-PCR analyzes revealed expression of the Sj myophilin-like protein mRNA in eggs, sporocysts, cercariae, hepatic schistosomula and adult worms. Confocal fluorescence microscopy localized the native protein to the muscle of the adult worm. In schistosome-infected rabbits, the rSj myophilin-like protein antibody level, assessed by ELISA, was elevated after infection but was reduced after praziquantel treatment. In humans, the myophilin-like protein antibody level was evaluated by ELISA in sera from 33 non-infected humans and 61 schistosomiasis patients; the results showed a highly significant difference between the two groups with a sensitivity of 57.4%. Taken together, the myophilin-like protein may prove useful for monitoring the therapeutic effect of praziquantel rather than in serodiagnosis of schistosomiasis.
Experimental Parasitology 06/2008; 119(1):117-24. · 2.12 Impact Factor
