RESUMEN
Objective:To evaluate the relationship between silent information regulator 1 (SIRT1) and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis.Methods:One hundred and fifty-two SPF-grade male C57BL/6J mice, aged 8 weeks, weighing 23-27 g, were divided into 4 groups ( n=38 each) using a random number table method: sham operation group (C group), sepsis group (S group), curcumin group (Cur group) and curcumin plus SIRT1 inhibitor EX527 group (CE group). Curcumin 200 mg/kg was administered by intragastric gavage every day in Cur group. Curcumin 200 mg/kg was administered by intragastric gavage every day and EX527 5 mg/kg was intraperitoneally injected in CE group. The equal volume of solvent dimethyl sulfoxide (DMSO) was given in C group and S group. Sepsis model was developed by cecal ligation and puncture (CLP) after 5 days of consecutive administration in anesthetized animals. Twenty mice in each group were randomly selected to observe the survival condition within 7 days after CLP. The bronchoalveolar lavage fluid (BALF) was collected at 24 h after developing the model to determine the concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6 and IL-18 (by enzyme-linked immunosorbent assay), and the lung tissues were obtained for microscopic examination of the pathological changes which were scored and for determination of wet-to-dry lung weight (W/D) ratio, contents of glutathione (GSH), malondialdehyde (MDA) and iron (by colorimetry), and expression of SIRT1, glutathione peroxidase 4 (GPX4) and Acyl-CoA synthetase long chain family member 4 (ACSL4) (by Western blot). Results:Compared with C group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH in lung tissues was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in S group ( P<0.05). Compared with S group, the 7-day survival rate after CLP was significantly increased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were decreased, the content of GSH was increased, the contents of MDA and iron were decreased, the expression of SIRT1 and GPX4 was up-regulated, and the expression of ACSL4 was down-regulated in Cur group ( P<0.05). Compared with Cur group, the 7-day survival rate after CLP was significantly decreased, the concentrations of TNF-α, IL-1β, IL-6 and IL-18 in BALF, W/D ratio and lung injury score were increased, the content of GSH was decreased, the contents of MDA and iron were increased, the expression of SIRT1 and GPX4 was down-regulated, and the expression of ACSL4 was up-regulated in CE group ( P<0.05). Conclusions:The mechanism by which curcumin attenuates acute lung injury may be related to activation of SIRT1 and further inhibition of ferroptosis in mice.
RESUMEN
Objective:To evaluate the role of silent information regulator 1 (SIRT1) in electroacupuncture (EA)-induced reduction of central post-stroke pain (CPSP) and the relationship with nod-like receptor pyrin domain containing 3 (NLRP3) in rats.Methods:Fifty SPF healthy male Sprague-Dawley rats, aged 6 weeks, weighing 180-220 g, were divided into 5 groups ( n=10 each) using a random number table method: sham operation group (group Sham), CPSP group, CPSP+ sham EA group (group SEA), CPSP+ EA group (group EA) and CPSP+ EA+ SIRT1 inhibitor EX527 group (group EX527). Type Ⅳ collagenase was injected into the right ventral posterolateral nucleus to establish the model of CPSP in CPSP, SEA, EA and EX527 groups.At 24 h after the model was established successfully, 30 min EA (frequency 2/15 Hz) stimulation of Neiguan, Renzhong and Sanyinjiao was performed once a day for 5 consecutive days in EA group.EA was performed at the points 5 mm lateral to the acupoints of Neiguan, Renzhong and Sanyinjiao in group SEA, and the other procedures were similar to those previously described in group EA.SIRT1 inhibitor EX527 5 mg/kg was injected intraperitoneally at 30 min before EA stimulation in group EX527, and the other procedures were similar to those previously described in group EA.At 1 day before the establishment of model (T 0) and at 1, 3 and 5 days after the establishment of model (T 1-3), the thermal withdrawal latency (TWL) and mechanical withdrawal threshold (MWT) were measured.The animals were then sacrificed and brain tissues were taken for determination of the expression of SIRT1, NLRP3 and interleukin (IL)-18 and IL-1β. Results:Compared with Sham group, the TWL was significantly shortened and the MWT was decreased at T 1-3, the expression of SIRT1 was down-regulated, and the expression of NLRP3, IL-18 and IL-1β was up-regulated in CPSP, SEA, EA and EX527 groups ( P<0.05). Compared with CPSP group, the TWL was significantly prolonged and the MWT was increased at T 1-3, the expression of SIRT1 was up-regulated, and the expression of NLRP3, IL-18 and IL-1β was down-regulated in EA group ( P<0.05), and no significant change was found in the parameters mentioned above in group SEA ( P>0.05). Compared with EA group, the TWL was significantly shortened and the MWT was decreased at T 1-3, the expression of SIRT1 was down-regulated, and the expression of NLRP3, IL-18 and IL-1β was up-regulated in EX527 group ( P<0.05). Conclusion:SIRT1 is involved in the process of EA-induced reduction of CPSP, which is related to inhibiting NLRP3 expression in rats.