Desulfovibrio vulgaris, a potent acetic acid-producing bacterium, increased by Astragalus polysaccharides to attenuate nonalcoholic fatty liver disease in mice / 中国药理学与毒理学杂志

OBJECTIVE Although the underlying mechanism is largely unknown, gut dysbiosis has emerged as a central initiator of obesity-related diseases including nonalcoholic fatty liver disease (NAFLD), type 2 diabetes and meta?bolic syndrome. The emerging evidence support the use of prebiotics like herb-derived polysaccharides for treating NAFLD by modulating gut microbiome. So, our study focused on the microbiota-dependent anti-NAFLD effect and the exact mechanisms of Astragalus polysaccharides (APS) extracted from Astragalus mongholicus Bunge in high-fat diet (HFD) fed mice. METHODS Co-housing experiment was used to assess the microbiota dependent anti-NAFLD effect of APS. Then, targeted metabolomics and metagenomics were adopted for determining short-chain fatty acids (SCFAs) and bacteria that were specifically enriched by APS. Further in vitro experiment was carried out to test the capacity of SCFAs-producing of identified bacterium. Finally, the anti-NAFLD efficacy of identified bacterium was tested in HFD fed mice. RESULTS Our results first demonstrated the anti-NAFLD effect of APS in HFD fed mice and the contribution of gut microbiota. Moreover, our results indicated that SCFAs, predominantly acetic acid were elevated in APS-supplemented mice and ex vivo experiment. Metagenomics revealed that D. vulgaris from Desulfovibrio genus was not only enriched by APS, but also a potent generator of acetic acid, which showed significant anti-NAFLD effects in HFD fed mice. In addition, D. vulgaris modulated the hepatic gene expression pattern of lipids metabolism, particularly suppressed hepatic fatty acid synthase (FASN) and CD36 protein expression. CONCLUSION APS enriched D. vulgaris is effective on attenuating hepatic steatosis possibly through producing acetic acid, and modulation on hepatic lipids metabolism in mice. Further studies are warranted to explore the long-term impacts of D. vulgaris on host metabolism and the underly?ing mechanism.

Investigation of modulating effect of Qingfei Paidu Decoction on host metabolism and gut microbiome in rats / 中国中药杂志

This study is to explore the effect of Qingfei Paidu Decoction(QPD) on the host metabolism and gut microbiome of rats with metabolomics and 16 S rDNA sequencing. Based on 16 S rDNA sequencing of gut microbiome and metabolomics(GC-MS and LC-MS/MS), we systematically studied the serum metabolites profile and gut microbiota composition of rats treated with QPD for continued 5 days by oral gavage. A total of 23 and 43 differential metabolites were identified based on QPD with GC-MS and LC-MS/MS, respectively. The involved metabolic pathways of these differential metabolites included glycerophospholipid metabolism, linoleic acid metabolism, TCA cycle and pyruvate metabolism. Meanwhile, we found that QPD significantly regulated the composition of gut microbiota in rats, such as enriched Romboutsia, Turicibacter, and Clostridium_sensu_stricto_1, and decreased norank_f_Lachnospiraceae. Our current study indicated that short-term intervention of QPD could significantly regulate the host metabolism and gut microbiota composition of rats dose-dependently, suggesting that the clinical efficacy of QPD may be related with the regulation on host metabolism and gut microbiome.

Effects of different intensity interval exercise of 6 weeks on body composition of obese rats / 中国应用生理学杂志

OBJECTIVE@#To investigate the effects of different intensity intermittent exercise on the body function of obese rats, and to provide basis for the prevention and treatment of obesity.@*METHODS@#Eighty SD rats were randomly divided into normal diet group (n=20) and high-fat diet group (n=60). After adaptive feeding for 8 weeks, 8 normal diet rats and 32 high-fat obese rats were selected for follow-up experiments. The experimental rats were randomly divided into 5 groups (n=8): control diet-sedentary (CS),with ordinary feed and without any exercise; high diet-sedentary (HS), with high-fat feed feeding and without any exercise; high diet-continual exercise(HC), 60 min/day,5 days/week with 6 weeks; high diet-long time-low frequency interval exercise(HLL), 30 min/time,twice/day (intermittent 6 h), 5 days/week with 6 weeks; high diet-short time-high frequency interval exercise(HSH), 20 min/ time, 3 times/d (intermittent 3 h), 5 days/week with 6 weeks. The training intensity of rats in each exercise group was 25 m/min. After 6 weeks, rats in each groups were weighed, and resting metabolic rate(RMR), fasting blood glucose(FBG), triglyceride(TG) and other biochemical indexes were detected, and fat and muscle weight were measured.@*RESULTS@#Before experiment, there were no significant differences in RMR, FBG and TG in each groups(P＞0.05).The body weight of HSH, HLL, HC and HS groups was higher than that of CS group (P＜0.05). After the experiment, RMR of the HSH,HLL and HC groups was significantly higher than that of HS and CS groups (P＜0.05), but without significant difference among the HSH,HLL and HC groups (P＞0.05).The body weight of HSH, HLL and HC groups was significantly lower than that of HS group (P＜0.05), but the three groups was not significant (P＞0.05); perirenal fat(PF), idymis fat(EF), perirenal fat/weight(PF/W) and epididymis fat/weight(EF/W) of HSH, HLL, HC group were significantly lower than those of HS group (P＜0.01), while there was no statistical difference among the three groups (P＞0.05). There was no significant difference in gastrocnemius(GM) and quadricep(QF) of each group (P＞0.05), gastrocnemius/weight(GM/W) and quadriceps/weight (QF/W) in HSH,HLL and HC groups were higher than those of HS group (P＜0.05),while there was no significant difference among HSH,HLL and HC groups (P＞0.05);FEB,TG of HSH,HLL,HC group were lower than those of CS and HS group (P＜0.05),but the difference with HS group was more significant (P＜0.01),there was no significant difference among training groups(P＞0.05).@*CONCLUSION@#6 weeks of intermittent exercise of different intensity had a good intervention effect on the body composition of obese rats, and high diet-short time-high frequency interval exercise (HSH) may be more effective.

Effect of hyperbaric oxygen preconditioning on spleen lymphocytes and cell adhesion molecules after skin transplantation in mice / 中国实验血液学杂志

The aim of this study was to explore the effect of hyperbaric oxygen (HBO) preconditioning on the rejection of skin allograft in mice and its molecular mechanism. BALB/c donor mice and C57BL/6 recipients received hyperbaric oxygen preconditioning once a day for 7 days. After skin transplantation, the recipients were treated with cyclosporine A (CsA) intraperitoneally. Immunofluorescent staining technique and flow cytometry were used to observe the influence HBO on percentage of spleen lymphocytes CD3+, CD4+, CD8+ and cell adhesion molecule LFA-1 (CD11a/CD18). The results showed that as compared with control, the numbers of CD3+, CD4+, CD8+, CD4+CD11a+, CD4+ CD18+, CD8+CD11a+, CD8+CD18+ lymphocytes of spleen decreased in HBO preconditioning groups and CsA group, and decreased markedly in HBO preconditioning combined with CsA group (p<0.05); the general state of recipient mice in HBO preconditioning combined with CsA group was better than that of recipient mice received HBO preconditioning or CsA only. It is concluded that the method of HBO preconditioning combined with traditional immunosuppressive agent CsA has remarkable advantage in inhibiting the rejection of skin graft. Its molecular protective mechanism is correlated with the expression of adhesive molecules on T cell subsets.

Screening of effective shRNA targeting TNF-alpha and constructing of recombinant plasmid / 中国实验血液学杂志

The objective of this study was to screen out the effective shRNA which can inhibit the gene expression of tumour necrosis factor-alpha (TNF-alpha), to construct the recombinant plasmid and to determine its sequence so as to provide the new approach for searching gene therapy of TNF-alpha related diseases. The primary macrophages were added into 15% DMEM, then cells were adjusted as 2 x 10(7) cells/L and were inoculated in 6-well plate with 3 ml/well, and were cultured at 37 degrees C in a fully humidified atmosphere with 5% CO(2). Cells were stimulated with lipopolysaccharide (LPS) and the concentration of TNF-alpha in the supernatant at different time points was determined by enzyme-linked immunosorbent assay (ELISA). The 5 synthesized DNA sequences which can be transcripted into shRNA were transfected into cells with lipofectamine 2000, then the cells were stimulated with LPS for 24 hours. The concentration of TNF-alpha in the supernatant and the expression of TNF-alpha mRNA were determined by ELISA and reverse transcription polymerase chain reaction (RT-PCR) respectively. The most effective shRNA was inserted into plasmid, and the recombinant plasmid was identified by sequence analysis. The results showed that the concentration of TNF-alpha in the supernatant reached peak after the stimulation with LPS for 24 hours. In the RNA interference group, the shRNA 1 was the most effective one, which could inhibit the expression of TNF-alpha by 59.46% and the expression of TNF-alpha mRNA by 61.2%. The recombinant plasmid was cloned and the sequence of interest was obtained. In conclusion, the most effective shRNA targeting TNF-alpha was successfully screened out and the recombinant plasmid was constructed. The recombinant plasmid may be helpful to search new gene therapy for TNF-alpha related disease.

Effect of hyperbaric oxygen on acute graft-versus-host disease after allogeneic bone marrow transplantation / 中国实验血液学杂志

The objective of this study was to investigate the function and mechanism of hyperbaric oxygen (HBO) in antagonizing acute graft-versus-host disease (aGVHD) and improving the rate of survival. The lethally irradiated C57BL/6 recipients were injected with bone marrow and lymphocyte of spleen from BALB/c donors and were treated with HBO, cyclosporine A (CsA) and methotrexate (MTX). T lymphocytes and subsets, adhesion molecules and cytokines were detected by flow cytometry, ELISA and RT-PCR respectively. The results showed that the survival rate in HBO group was much higher than that in allogenetic bone marrow transplantation (allo-BMT) group and CsA + MTX group; the numbers of CD3(+), CD4(+), CD8(+), CD4(+)CD11a(+), CD4(+)CD18(+), CD8(+)CD11a(+), CD8(+)CD18(+) lymphocytes in spleen were decreased markedly by HBO and CsA + MTX (p < 0.05); the levels of IL-2 and TNFalpha mRNA and their serum concentrations in HBO group were much lower than those in allo-BMT group but were higher than those in CsA + MTX group; the levels of IL-4 and IL-10 mRNA in HBO group were much higher than those in allo-BMT group and CsA + MTX group. It is concluded that HBO has more remarkable advantage in improving the rate of survival than CsA + MTX, its mechanism of anti-aGVHD is tightly correlated with the transform of T cell and its subsets and the expression of adhesion molecules and cytokines.