Relationship between SIRT1 and ferroptosis during curcumin-induced reduction of acute lung injury in a mouse model of sepsis / 中华麻醉学杂志

ABSTRACT

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.