Metformin Attenuates Brain Injury by Inhibiting Inflammation and Regulating Tight Junction Proteins in Septic Rats
CELL JOURNAL
Authors: Hassan, Fatima Ismail; Didari, Tina; Baeeri, Maryam; Gholami, Mahdi; Haghi-Aminjan, Hamed; Khalid, Madiha; Navaei-Nigjeh, Mona; Rahimifard, Mahban; Solgi, Sara; Abdollahi, Mohammad; Mojtahedzadeh, Mojtaba
Abstract
Objective: Metformin has a potent inhibitory activity against inflammation and oxidative stress, which inevitably occur in sepsis-associated encephalopathy (SAE). The precise mechanisms underlying neuroprotective effects of metformin in SAE, are still unclear. In the present work, the protective effect of metformin on SAE using cecal ligation and puncture (CLP) model of sepsis, was assessed. Materials and Methods: In this experimental study, CLP procedure was performed in Wistar rats and 50 mg/kg metformin was administered immediately. Specific markers of sepsis severity, inflammation, blood brain barrier (BBB) dysfunction, and brain injury, were investigated. Specific assay kits and real-time polymerase chain reaction (RT-PCR) were used. Histopathological assessment was also carried out. Results: Treatment with metformin decreased murine sepsis score (MSS), lactate, platelet lymphocyte ratio (PLR), and high mobility group box (HMGB1) levels. The expression levels of claudin 3 (Cldn3) and claudin 5 (Cldn5) were increased following treatment with metformin. Metformin decreased the expression of S100b, neuron specific enolase (Nse), and glial fibrillary acidic protein (Gfap). Conclusion: Our study suggests that metformin may inhibit inflammation and increase tight junction protein expressions which may improve BBB function and attenuate CLP-induced brain injury. Hence, the potential beneficial effects of metformin in sepsis, should be considered in future.
Effects of mild hypothermia on serum HMGB1 of brain-dead donors and its impact on kidney transplantation recipients
MEDICINE
Authors: Shan, Hui; Zhang, Xin; Lin, Zhe-Min; Wang, Xue-Zhu; Mi, Zi-Xin; Wang, Ya-Ping; Tang, Zi-Ren; Zhang, Xiao-Dong
Abstract
Investigate the effect of mild hypothermia on serum inflammatory factor HMGB1 of brain-dead donors, and its significance for renal transplantation recipients. In our hospital between January 2018 and January 2019 up to the standard of brain death donor (aged 18 to 65 years old) prospective cohort study, brain death donor were randomly divided into mild hypothermia group and the non-mild hypothermia group. Serum were collected from donor at different periods, and enzyme-linked immunoassay (ELISA) was used to determine the serum HMGB1 concentration to compare the difference between the 2 donor groups. The early recovery of renal function after renal transplantation was followed up, and the incidence of delayed graft function (DGF) and early recovery of renal function were compared between the 2 groups. The correlation between donor HMGB1 and recipient DGF was analyzed. Between 17 donors in the mild hypothermia group and 17 in the non-mild hypothermia group, there were no statistically significant differences in the age, perioperative urine volume and ICU stay between the 2 groups. After mild hypothermia treatment, serum HMGB1 levels of brain death donors were significantly decreased. While in non-mild hypothermia brain death donor group without treatment, serum HMGB1 was significantly increased. There were no statistically significant differences in age and preoperative creatinine between the 2 recipient groups, including 33 patients in the mild hypothermia group and 34 patients in the non-mild hypothermia group. DGF incidence was lower in mild hypothermia group comparing with non-mild hypothermia group with statistical significance. The levels of HMGB1 from donor before procurement is correlated with the occurrence of DGF of the recipient. Mild hypothermia therapy can reduce the levels of serum HMGB1, improve the function of donor organs. The levels of HMGB1 before donor procurement can be used to predict the occurrence of DGF in kidney transplant recipients. Our study shows that HMGB1 can be potentially used as therapeutic target of early intervention for brain death donors. Furthermore, mild hypothermia therapy can be applied in the maintenance of brain death donors for kidney transplant recipient to improve the successful rate of transplantation.