ABSTRACT
Objective:To evaluate the effects of berberine on necroptosis of non-alcoholic fatty liver disease in mice and its relationship with adenosine monophosphate-activated protein kinase(AMPK)/ signal transducer and activator of transcription 6(STAT6) pathway.Methods:Twenty-five 8-week-old male C57BL/6N mice were divided into control group, steatotic liver group, berberine treatment group(200 mg·kg -1·d -1), AMPK inhibitor Compound C treatment group(0.2 mg·kg -1·d -1), and STAT6 inhibitor AS1517499 treatment group(10 mg·kg -1·d -1). After 12 weeks of intervention, the mice and liver tissue were weighed, and serum aspartate aminotransferase(AST), alanine aminotransferase(ALT), triglyceride, tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β) as well as liver malondialdehyde and superoxide dismutase were measured; liver tissue HE, Masson, and oil red O staining were performed. Western blotting was used to detect the expressions of necroptosis related proteins[receptor interaction protein kinase 3(RIPK3), phosphorylated(p-) mixed lineage kinase domain-like(MLKL)], AMPK, p-AMPK, and p-STAT6. Results:Compared with control group, the steatotic liver group had higher quality of liver and liver index, and higher levels of serum AST, ALT, triglyceride, TNF-α, IL-1β, and oxidative stress( P<0.05); Liver tissue was full of cavity changes and inflammatory cell infiltration, widely distributed red lipid droplets and obvious blue fiber dyeing; The expressions of RIPK3 and p-MLKL were up-regulated ( P<0.05), but the levels of p-AMPK and p-STAT6 were relatively reduced ( P<0.05). Compared with the steatotic liver group, berberine intervention decreased liver quality and liver index, improved liver function, reduced blood lipid levels, pro-inflammatory factor expression and oxidative stress level, and significantly alleviated the degree of liver steatosis and fibrosis, the levels of RIPK3 and p-MLKL ( P<0.05), while the expressions of p-AMPK and p-STAT6 were increased significantly ( P<0.05). As compared with the berberine treatment, AMPK and STAT6 inhibitor treatment could offset the protective effect of berberine on steatotic liver, moreover, the expressions of RIPK3 and p-MLKL were increased ( P<0.05). There was no statistical difference in AMPK total protein content among the five groups ( P>0.05). Conclusion:Berberine can activate AMPK/STAT6 pathway to inhibit the necroptosis of hepatocyte, thus plays a protective role on non-alcoholic fatty liver disease in mice.
ABSTRACT
Objective:To evaluate the effect of hepatic ischemia-reperfusion (I/R) rats-derived exosomes on microglial pyroptosis.Methods:Twenty clean-grade healthy male Sprague-Dawley rats, aged 2-3 weeks, weighing 20-50 g, were divided into 2 groups ( n=10 each) using a random number table method: sham operation group (group S) and hepatic I/R group (group I/R). The serum of rats in S group and I/R group was collected, and exosomes were isolated from the sera using differential centrifugations.Microglial cells were co-cultured with PKH26-labeled exosomes for 6 h. The intake of exosomes in microglial cells was determined using immunofluorescence staining.Primary microglial cells were seeded onto 6-well culture plates at a density of 5×10 5 cells/ml and were divided into 4 groups ( n=6 each) using a random number table method: control group (group C), 10 7 cells/ml I/R-exosomes treated group (group 10 7), 10 8 cells/ml I/R-exosomes treated group (group 10 8), and 10 9 cells/ml I/R-exosomes treated group (group 10 9). Microglia in each group were co-cultured with the corresponding concentration of I/R-exosomes for 6 h. The expression of NOD-like receptor family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), cleaved-caspase-1 and gasdermin-D (GSDMD) was detected using Western blot.Primary microglial cells were divided into 3 groups ( n=24 each) by a random number table method: control group (group C), sham operation-exosomes treated group (group S-exosome) and I/R-exosomes treated group (group I/R-exosome). In S-exosome group and I/R-exosome group, exosomes 10 8 cells/ml in S group and I/R group were given, respectively, to incubate cells for 6 h. The expression of NLRP3, ASC and GSDMD mRNA was determined by real-time polymerase chain reaction, and the levels of interleukin-18 (IL-18), IL-1β and tumor necrosis factor-alpha (TNF-α) in the cell culture supernatant were measured by enzyme-linked immunosorbent assay. Results:The results from immunofluorescence staining showed that I/R-exosomes colocalized with microglia.The 10 8 cells/ml I/R-exosomes and 10 9 cells/ml I/R-exosomes up-regulated the expression of NLRP3, ASC, GSDMD and cleaved-caspase-1 in microglial cells ( P<0.01). Compared with group C and group S-exosome, the expression of NLRP3, ASC and GSDMD mRNA in microglial cells was up-regulated, and the levels of IL-18, IL-1β and TNF-α in the supernatant were elevated in group I/R-exosome ( P<0.01). Conclusions:Hepatic I/R rats-derived exosomes can promote microglial pyroptosis.
ABSTRACT
Objective:To evaluate the relationship between serum exosomes and microglial pyroptosis during brain injury in a young rat model of hepatic ischemia-reperfusion (I/R).Methods:Forty-six clean-grade healthy male Sprague-Dawley rats, aged 2-3 weeks, weighing 40-60 g, were allocated into 4 groups using a random number table method: sham operation group (group S, n=10), hepatic I/R group (group I/R, n=13), treatment with serum exosome in sham-operated young rat group (group S-Exosome, n=10), and treatment with serum exosomes in young rats with I/R group (group I/R-Exosome, n=13). The common trunk of the portal vein, left hepatic artery and bile duct was clamped for 60 min resulting in ischemia of 70% of the liver in anesthetized animals.After 6 h of reperfusion, the serum was collected to extract exosomes in S group and I/R group, and the serum exosome suspension 100 μl of S group and I/R group was injected through the tail vein in S-Exosome group and I/R-Exosome group, respectively.The expression of serum exosome marker proteins CD9 and CD81 was determined by Western blot in S group and I/R group.Serum and hippocampi were obtained from each group at 6 h after the corresponding treatment.The expression of NOD-like receptor protein 3 (NLRP3), gasdermin D (GSDMD), pro-caspase-1, cleaved-caspase-1, and apoptosis-associated speck-like protein containing CARD (ASC) in the hippocampus was detected using Western blot, and the expression of GSDMD in hippocampal tissues was determined by immunohistochemistry.The levels of interleukin-1beta (IL-1β), interleukin-18 (IL-18) and tumor necrosis factor-α (TNF-α) in serum and hippocampal tissues and S100β and NSE in serum were determined by enzyme-linked immunosorbent assay.In group I/R-Exosome, 3 rats were selected, and their serum exosomes were extracted, labeled with PKH26 red fluorescence and then injected via the tail vein, and the co-localization between exosomes and microglia was identified by immunofluorescence technique. Results:Compared with group S, the expression of serum CD9 and CD81 was significantly up-regulated in group I/R, the expression of NLRP3, GSDMD, cleaved-caspase-1 and ASC in hippocampal tissues was significantly up-regulated, the levels of IL-18, IL-1β and TNF-α in serum and hippocampal tissues and S100β and NSE in serum were increased in I/R and I/R-Exosome groups ( P<0.05), and no significant change was found in the parameters mentioned above in group S-Exosome ( P>0.05). The positive expression of GSDMD was significantly increased in I/R and I/R-Exosome groups ( P<0.05), no positive expression of GSDMD was found in S and S-Exosome groups ( P>0.05), and the results of immunofluorescence showed the co-localization between exosomes and microglia. Conclusions:The mechanism by which hepatic I/R induces brain injury may be related to serum exosomes-mediated microglial pyroptosis in young rats.
ABSTRACT
Objective:To evaluate the role of silencing information regulator 1 (SIRT1)/nuclear factors E2-related factor2 (Nrf2) signaling pathway in berberine-induced reduction of renal ischemia-reperfusion (I/R) injury in mice.Methods:Thirty SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 18-22 g, were divided into 5 groups ( n=6 each) using a random number table method: sham operation group (S group), renal I/R group (RIR group), berberine+ I/R group (B group), berberine+ I/R+ SIRT1 inhibitor EX527 group (BE group) and berberine+ I/R+ Nrf2 inhibitor ATRA group (BA group). After the right kidney was removed, the left renal artery was clamped for 45 min followed by reperfusion to establish the model of renal I/R injury.In B, BE, and BA groups, berberine 100 mg·kg -1·d -1 was given for intragastric administration at 14 days before surgery.In group BE and group BA, EX527 5 mg·kg -1·d -1 and ATRA 10 mg·kg -1·d -1 were injected intraperitoneally at 3 days before surgery, respectively.The equal volume of normal saline was given for 14 consecutive days in group S and group RIR.Blood samples were collected from orbital vein at 24 h of reperfusion for measurement of serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations, for determination of the interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) contents (by enzyme-linked immunosorbent assay) and expression of SIRT1, Nrf2, apoptosis-associated speck-like protein containing CARD (ASC), caspase-1, nucleotide-binding oligomerization domain-like receptor containing pyrin domain (NLRP3) (by Western blot) and for examination of the pathological changes of renal tubules (with a light microscope). The damage to the renal tubules was scored. Results:Compared with group S, the concentrations of serum Cr and BUN, the contents of renal IL-1β and TNF-α and renal tubular injury score were significantly increased in RIR, B, BE and BA groups, the expression of SIRT1, Nrf2, ASC, caspase-1 and NLRP3 was up-regulated in RIR, BE and BA groups, and the expression of SIRT1, Nrf2, caspase-1 and NLRP3 was up-regulated in group B ( P<0.05). Compared with group RIR, the concentrations of serum Cr and BUN, the contents of renal IL-1β and TNF-α and renal tubular injury score were significantly decreased in B, BE and BA groups, the expression of SIRT1 and Nrf2 in group B, Nrf2 and ASC in BE group and SIRT1, ASC and caspase-1 in BA group was up-regulated, and the expression of ASC, caspase-1 and NLRP3 in group B, SIRT1 and NLRP3 in BE group and Nrf2 in BA group was down-regulated ( P<0.05). Compared with group B, the serum concentrations of Cr and BUN, the contents of IL-1β and TNF-α and renal tubular injury score were significantly increased in BE and BA groups, the expression of ASC, caspase-1 and NLRP3 in BE and BA groups was up-regulated, and the expression of SIRT1 in BE and Nrf2 in BA groups was down-regulated ( P<0.05). Conclusion:SIRT1/Nrf2 signaling pathway is involved in the process of berberine-induced reduction of renal I/R, which is related to inhibiting pyroptosis in mice.
ABSTRACT
Objective To evaluate the role of sirtuin 3 ( SIRT3)∕forkhead box O3α ( FOXO3α) signaling pathway in dexmedetomidine-induced reduction of hepatic ischemia-reperfusion ( I∕R) injury in mice. Methods Forty clean-grade C57BL∕6 mice of both sexes, aged 2 weeks, weighing 6-8 g, were di-vided into 4 groups (n＝10 each) using a random number table method: sham operation group (group S), hepatic I∕R group ( group I∕R), dexmedetomidine group ( group D) and SIRT3 inhibitor 3-TYP plus dexmedetomidine group (group T+D). Portal vein and hepatic artery supplying left and middle lobes of the liver and biliary tract were clamped resulting in ischemia of 70% of the liver in anesthetized rats. Normal sa-line 0. 25 ml was intraperitoneally injected at 1 h before establishing model, and 30 min later dexmedetomi-dine 50 μg∕kg (diluted to 0. 25 ml in normal saline) was intraperitoneally injected in group D. In group T+D, 3-TYP 5 mg∕kg (diluted to 0. 25 ml in normal saline) was intraperitoneally injected at 1 h before estab-lishing model, and 30 min later dexmedetomidine 50 μg∕kg (diluted to 0. 25 ml in normal saline) was in-traperitoneally injected. Mice were selected at 6 h after reperfusion, blood samples were obtained through eyeball, and the mice were then sacrificed and kidneys were removed for determination of the serum concen-trations of creatinine (Cr) and blood urea nitrogen (BUN), cell apoptosis (by TUNEL), malondialdehyde (MDA) content (using thiobarbituric acid method), superoxide dismutase (SOD) activity (by xanthine oxidase method), and acetylation of FOXO3α in renal tissues (by using immunoprecipitation) and for ex-amination of the pathologic changes. The damage to renal tubules was scored. Apoptosis index ( AI) was calculated. Results Compared with group S, the renal tubular damage score and AI were significantly in-creased, serum concentrations of Cr and BUN were increased, the content of MDA was increased, the ac-tivity of SOD was decreased, and the acetylation of FOXO3α was decreased in I∕R, D and T+D groups ( P＜0. 05). Compared with group I∕R, the renal tubular damage score and AI were significantly decreased, serum concentrations of Cr and BUN were decreased, the content of MDA was decreased, the activity of SOD was increased, and the acetylation of FOXO3α was decreased in group D (P＜0. 05), and no signifi-cant change was found in the parameters mentioned above in group T+D (P＞0. 05). Compared with group D, the renal tubular damage score and AI were significantly increased, serum concentrations of Cr and BUN were increased, the content of MDA was increased, the activity of SOD was decreased, and the acetylation of FOXO3α was decreased in group T+D ( P＜0. 05). Conclusion Activation of SIRT3∕FOXO3α signaling pathway is involved in dexmedetomidine-induced reduction of hepatic I∕R injury in mice.