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The mTOR pathway serves an important role in the development of insulin resistance induced by obesity. Exercise improves obesity‑associated insulin resistance and hepatic energy metabolism; however, the precise mechanism of this process remains unknown. Therefore, the present study investigated the role of rapamycin, an inhibitor of mTOR, on exercise‑induced expression of hepatic energy metabolism genes in rats fed a high‑fat diet (HFD). A total of 30 male rats were divided into the following groups: Normal group (n=6) fed chow diets and HFD group (n=24) fed an HFD for 6 weeks. The HFD rats performed exercise adaptation for 1 week and were randomly divided into the four following groups (each containing six rats): i) Group of HFD rats with sedentary (H group); ii) group of HFD rats with exercise (HE group); iii) group of HFD rats with rapamycin (HR group); and iv) group of HFD rats with exercise and rapamycin (HER group). Both HE and HER rats were placed on incremental treadmill training for 4 weeks (from week 8‑11). Both HR and HER rats were injected with rapamycin intraperitoneally at the dose of 2 mg/kg once a day for 2 weeks (from week 10‑11). All rats were sacrificed following a 12‑16 h fasting period at the end of week 11. The levels of mitochondrial and oxidative enzyme activities, as well as of the expression of genes involved in energy metabolism were assessed in liver tissues. Biochemical assays and oil red staining were used to assess the content of hepatic triglycerides (TGs). The results indicated that exercise, but not rapamycin, reduced TG content in the liver of HFD rats. Further analysis indicated that rapamycin reduced the activity of cytochrome c oxidase, but not the activities of succinate dehydrogenase and β‑hydroxyacyl‑CoA dehydrogenase in the liver of HFD rats. Exercise significantly upregulated the mRNA expression of peroxisome proliferator‑activated receptor γ coactivator 1 β, while rapamycin exhibited no effect on the mRNA expression levels of hepatic transcription factors associated with energy metabolism enzymes in the liver of HFD rats. Collectively, the results indicated that exercise reduced TG content and upregulated mitochondrial metabolic gene expression in the liver of HFD rats. Moreover, this mechanism may not involve the mTOR pathway.

Background: Artemisia annua is the major source for artemisinin production. The artemisinin content in A. annua is affected by different types of light especially the UV light. UVR8, a member of RCC1 gene family was found to be the UV-B receptor in plants. The gene structures, evolutionary history and expression profile of UVR8 or RCC1 genes remain undiscovered in A. annua. Results: Twenty-two RCC1 genes (AaRCC1) were identified in each haplotype genome of two diploid strains of A. annua, LQ-9 and HAN1. Varied gene structures and sequences among paralogs were observed. The divergence of most RCC1 genes occurred at 46.7 – 51 MYA which overlapped with species divergence of core Asteraceae during the Eocene, while no recent novel RCC1 members were found in A. annua genome. The number of RCC1 genes remained stable among eudicots and RCC1 genes underwent purifying selection. The expression profile of AaRCC1 is analogous to that of Arabidopsis thaliana (AtRCC1) when responding to environmental stress. Conclusions: This study provided a comprehensive characterization of the AaRCC1 gene family and suggested that RCC1 genes were conserved in gene number, structures, constitution of amino acids and expression profiles among eudicots. [ABSTRACT FROM AUTHOR]

Background. Ursolic acid (UA) is an antitumor component derived from Chinese herbal medicine; this study is to observe the effects of UA on epithelial-mesenchymal transition (EMT) in gastric cancer. Methods. (1) In vitro experiments: 25μmol/L and 50μmol/L UA were applied to BGC-823, AGS, MGC-803, and HGC-27 cells; MTT staining, Transwell assay, and flow cytometry were used to assess cell proliferation, cell migration, and apoptosis, respectively. Western blot was performed to detect the expressions of N-Cadherin, Vimentin, Snail, Twist, Axl, p-Axl, IKK, p-IKK, NF-κB, and p-NF-κB. (2) In vivo experiments: Ten BALB/c-nu mice were used to establish gastric cancer xenograft model. Five were orally given UA for 4 weeks and five were given normal saline. Expressions of N-Cadherin and Snail were examined by immunohistochemical assay; expressions of N-Cadherin, Snail, Twist, Axl, p-Axl, IKK, and p-IKK were detected by Western blot. Results. (1) UA inhibited cell proliferation in BGC-823 and HGC-27 cells in dose-dependent manners. (2) UA inhibited cell migration in BGC-823, AGS, and MGC-803 cells while inducing apoptosis in BGC-823 cells. (3) UA significantly decreased the expressions of N-Cadherin, Vimentin, Snail, Twist p-Axl, p-IKKα/β, and p-NF-κB in BGC-823 and MGC-803 cells. (4) UA distinctly decreased the expressions of N-Cadherin, Snail, p-Axl, and p-IKKα/β in gastric cancer xenograft model rats. Conclusion. UA can effectively inhibit the proliferation and migration and induce apoptosis of gastric cancer cells. The antitumor effect of UA is conducted by EMT inhibition, which may be associated with the regulation of Axl/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

The insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE), commonly associated with many diseases, is believed to have affected human adaptation to environmental changes during the out-of-Africa expansion. APOBEC3B (A3B), a member of the cytidine deaminase family APOBEC3s, also exhibits a variable gene insertion/deletion polymorphism across world populations. Using data available from published reports, we examined the global geographic distribution of ACE and A3B genotypes. In tracking the modern human dispersal routes of these two genes, we found that the variation trends of the two I/D polymorphisms were directly correlated. We observed that the frequencies of ACE insertion and A3B deletion rose in parallel along the expansion route. To investigate the presence of a correlation between the two polymorphisms and the effect of their interaction on human health, we analyzed 1199 unrelated Chinese adults to determine their genotypes and other important clinical characteristics. We discovered a significant difference between the ACE genotype/allele distribution in the A3B DD and A3B II/ID groups (P = 0.045 and 0.015, respectively), indicating that the ACE Alu I allele frequency in the former group was higher than in the latter group. No specific clinical phenotype could be associated with the interaction between the ACE and A3B I/D polymorphisms. A3B has been identified as a powerful inhibitor of Alu retrotransposition, and primate A3 genes have undergone strong positive selection (and expansion) for restricting the mobility of endogenous retrotransposons during evolution. Based on these findings, we suggest that the ACE Alu insertion was enabled (facilitated) by the A3B deletion and that functional loss of A3B provided an opportunity for enhanced human adaptability and survival in response to the environmental and climate challenges arising during the migration from Africa. [ABSTRACT FROM AUTHOR]