ABSTRACT
Objective To investigate the improvement effect of n-3 polyunsaturated fatty acid (n-3 PUFA) on rat nonalcoholic fatty liver disease(NAFLD) induced by high fat diet.Methods Thirty Wister male rats were divided into the control group,model group and n-3 PUFA group.The high fat feeding was adopted to establish NAFLD model.After 20 weeks of experiment,7 cases were extracted from each group for detecting serum and liver total cholesterol (TC) and triacylglyceride(TG);other 3 cases were performed the liver HE staining,the levels of MCP-1,iNOS,TNF-α mRNA protein were detected by using the Real time quantitative PCR(qPCR) and Western blot.Results The TC and TG levels in serum and livers of the model group were significantly higher than those in the control group(P＜0.01),but which were evidently decreased after adding n-3 PUFA(P＜0.05).The HE staining clearly observed the rat hepatic cells fatty degeneration in the model group,while polyunsaturated fatty acid had obvious improvement effect on it.The inflammatory molecule MCP-1,iNOS,TNF-α gene expression levels in the model group were significantly higher than those in the control group(P＜0.05),while the expression levels of MCP-1,iNOS and TNF-α in the n-3PUFA group were significantly decreased compared with the model group.Conclusion High fat feeding can cause the severe fatty degeneration in rat liver,but polyunsaturated fatty acid can play obvious improvement effect.
ABSTRACT
Objective To investigate the improvement effect of n-3 polyunsaturated fatty acid (n-3 PUFA) on rat nonalcoholic fatty liver disease(NAFLD) induced by high fat diet.Methods Thirty Wister male rats were divided into the control group,model group and n-3 PUFA group.The high fat feeding was adopted to establish NAFLD model.After 20 weeks of experiment,7 cases were extracted from each group for detecting serum and liver total cholesterol (TC) and triacylglyceride(TG);other 3 cases were performed the liver HE staining,the levels of MCP-1,iNOS,TNF-α mRNA protein were detected by using the Real time quantitative PCR(qPCR) and Western blot.Results The TC and TG levels in serum and livers of the model group were significantly higher than those in the control group(P＜0.01),but which were evidently decreased after adding n-3 PUFA(P＜0.05).The HE staining clearly observed the rat hepatic cells fatty degeneration in the model group,while polyunsaturated fatty acid had obvious improvement effect on it.The inflammatory molecule MCP-1,iNOS,TNF-α gene expression levels in the model group were significantly higher than those in the control group(P＜0.05),while the expression levels of MCP-1,iNOS and TNF-α in the n-3PUFA group were significantly decreased compared with the model group.Conclusion High fat feeding can cause the severe fatty degeneration in rat liver,but polyunsaturated fatty acid can play obvious improvement effect.
ABSTRACT
Objective To investigate the role of receptor for advanced glycation end products (RAGE)/NF-κB signaling pathway in mediating lysophosphatidylcholine (LPC)-induced TGF-β1 expression in human retinal endothelial progenitor cells (HEPCs).Methods Human retinal endothelial cells (HERCs)were transfected with siRNA for RAGE siRNA or added NF-κB in-hibitor pyrrolidine dithiocarbamate (PDTC)in the presence or absence of LPC,the expressions of TGF-β1 and RAGE genes were analyzed by qPCR and Western blot.Results LPC could increase the expression of RAGE and TGF-β1 gene in HERCs.The RAGE gene after silence could significantly decrease the expression of LPC-induced RAGE and TGF-β1 .Adding NF-κB inhibitor PDTC significantly reduced LPC-induced RAGE and TGF-β1 expression in HERCs.Conclusion RAGE/NF-κB signaling pathway plays an important role in mediating LPC induced TGF-β1 gene expression in HERCs.
ABSTRACT
Objective To investigate the mechanism of pioglitazone preventing diabetes and the role of nuclear factor of actived T cells (NFAT) on non-obese diabetic(NOD) mice .Methods (1)Female NOD mice at 4 weeks of age were randomly divided into pioglitazone group(n=21) and control group(n=21) .The accumulative diabetes incidence was followed-up to 30 weeks of age in each group of NOD mice .(2)Pancreas were removed from NOD mice at 12 weeks of age in each group(n=15) to score insulitis se-verity by routine HE staining .IL-4 ,IFN-γand peroxisome proliferator-activated receptor γ(PPARγ) mRNA levels in spleens were tested by RT-PCR .IL-4 and IFN-γlevels in sera ,the activity of PPARγand NFATc1 nuclear protein in spleens were measured by enzyme linked immunosorbent assay (ELISA) .Results (1) At 15 weeks of age ,the diabetes incidence was 4 .76% in pioglitazone group ,and 33 .33% in control group(P0 .05) .(2) At 12 weeks of age ,the insulitis score in pioglitazone group was lower than that in control group[(1 .79 ± 0 .75) vs .(2 .38 ± 0 .66) ,P<0 .05] .(3) IFN-γ mRNA level in pioglitazone group was lower than that in control group[(0 .16 ± 0 .07) vs .(0 .53 ± 0 .26) ,P<0 .05] ,and PPARγmRNA level in pioglitazone group was higher than that in control group(0 .91 vs .0 .25 ,P<0 .05) .(4)IFN-γ level in pioglitazone group was lower than that in control group [(561 .05 ± 78 .61)pg/mL vs .(666 .43 ± 28 .42)pg/mL ,P<0 .05] .(5)At 12 weeks of age ,the spleen PPARγnuclear protein activity in pioglitazone group was higher than that in control group [(0 .05 ± 0 .01) vs .(0 .02 ± 0 .01) ,P<0 .05)] ,and NFATc1 nuclear protein activity was low-er than that in control group[(0 .23 ± 0 .04) vs .(0 .33 ± 0 .04) ,P<0 .05] .Conclusion Pioglitazone could activate PPARγ nuclear protein ,inhibit activity of NFATc1 nuclear protein ,downregulate IFN-γ,diminish Th cells deviating to Th1 ,and sequently prevents insulitis and diabetes onset in NOD mice .
ABSTRACT
Objective To investigate the mechanism of preventing islet β-cell apoptosis in NOD mice with pioglitazone.Methods Female NOD mice at 4 weeks of age were divided into pioglitazone group ( n =21,0.02％pioglitazone was added into the feed ) and control group ( n =21,fed with regular diet).The accumulative incidence of diabetes was followed-up to 52 weeks of age in each group of NOD mice.Pancreas was removed from NOD mice at 12 weeks of age in each group ( n =15 ) to score severity of insulitis by routine H-E staining.The apoptotic β-cells in islets were observed with double-labeling technique of TUNEL in situ combined with standard sensitive avidin-biotin complex (sABC) immunohistochemical method.The spleens were taken for cell culture; IL-4 and IFN-γ levels in sera and supernatants of cultured splenocyte,the activity of PPARγ and NF-κB nuclear proteins in cultured splenocyte were measured by ELISA.Results (1)At 30 and 52 weeks of age,the respective incidences of diabetes were 57.1％ and 76.2％ in pioglitazone group,and 76.2％ and 90.5％ in control group ( all P＞0.05 ).At 15 weeks of age,the incidence became 4.8％ in pioglitazone group,and 33.3 ％ in control group ( P =0.045 ).( 2 ) At 12 weeks of age,the percentages of non infiltrated islet and peri-insulitis islet in pioglitazone group were higher than those in control group ( 14.73％ vs 5.69％,P＜0.01 ; and 26.02％ vs 15.72％,P＜0.01 ),and that of intraislet insulitis was lower than that in control group ( 59.25％ vs 78.59％,P＜0.01 ).The percentage of apoptotic β-cell in pioglitazone group was lower than that in control group( 6.17％ ±3.62％ vs 10.62％ ±4.43％,P=0.008 ).(3) In sera,IFN-γ level in pioglitazone group was lower than that in control group [( 561.05±78.61 ) vs ( 666.43 ± 28.42 ) pg/ml,P =0.045].In cultured splenocyte supernatant,the level of IFN-γ in pioglitazone group was lower than that in control group[(605.84+65.60) vs (692.20+44.98) pg/ml,P=0.041].(4) In cultured splenocyte,PPARγ nuclear protein activity in pioglitazone group was higher than that in control group ( 0.06 ± 0.01 vs 0.03 ± 0.01,P =0.013 ),and NF-κB nuclear protein activity was lower than that in control group ( 0.03 ± 0.01 vs 0.08± 0.01,P =0.001 ).Conclusions Pioglitazone activates PPARγ nuclear protein,inhibits activity of NF-κB nuclear protein,downregulates IFN-γ,diminishes differeutiation of Th cells to Th1,and subsequently prevents insulitis and β-cell apoptosis in NOD mice.