Effects of Dexmedetomidine on Cognitive Function, Oxidative Stress and Brain Protection in Patients Undergoing Craniocerebral Surgery

Background: The protective mechanism of dexmedetomidine on the brains of patients undergoing craniocerebral surgery remains unclear. The aim of this study was to examine the impact of dexmedetomidine on cognitive function, oxidative stress, and brain protection in such patients. Methods: Fifty-four patients who underwent craniocerebral surgery at our hospital from January 2020 to June 2023 were retrospectively selected as study subjects. They were divided into two groups: the control group (n = 27) and the study group (n = 27), based on different auxiliary anesthesia protocols. Patients in the study group received dexmedetomidine before anesthesia induction, using a midline intravenous pump to assist anesthesia, while the control group received an equivalent amount of normal saline. The remaining anesthesia induction and maintenance protocols were consistent for both groups. Cognitive function was assessed using the Mini Mental State Examination (MMSE) before and 1 day after surgery for both groups. Oxidative stress indicators, including malondialdehyde (MDA), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) levels in the serum of both groups, were measured using enzyme-linked immunosorbent assay (ELISA). Additionally, changes in postoperative brain injury indicators, namely neuron-specific enolase (NSE) and central nervous system-specific protein (S100β), were detected and compared in the serum of both groups. Concurrently, postoperative adverse reactions were recorded for both groups. Results: The MMSE scale scores of both groups of patients 24 hours after surgery were significantly lower than those before surgery. However, the MMSE scale scores of the study group patients were notably higher than those in the control group, with a statistically significant difference (p < 0.05). One hour after surgery, the serum levels of MDA, GSH-Px, and SOD in both groups of patients were significantly elevated compared to pre-surgery levels. ... (AU)

Effect of metformin on connexin43 expression in H9c2 cells cultured with high glucose / 中国药理学通报

Aim To investigate the effect of metformin (Met) on connexin43(Cx43) expression in H9c2 cells cultured with high glucose and the relevant mecha-nisms.Methods Rat myocardial cells H9c2 were cul-tured with high glucose , then combined with 3μmol· L-1 and 5 μmol · L-1 of Met for 24 h respectively . The viability and toxicity of H9c2 cells were detected by MTT and LDH , respectively .The expression and distribution of Cx43 were detected by immunofluores-cence staining .The intracellular oxygen species reac-tive ( ROS) level was detected by fluorescencemicrosco-py.And the expression of Cx43, P-AMPK, AMPK and GAPDH was determined by Western blot .Results The viability of H9c2 cells was increased and the level of intracellular ROS was decreased in Met group , while there existed no significant difference in LDH release among groups.Met significantly increased the phos-phorylation of AMPK and the expression of Cx 43, and improved the distribution of Cx 43 also.Conclusion The beneficial effect of Met on cardiovascular system in diabetic patients may via up-regulating the expression of Cx43 and down-regulating of intracellular ROS through activation of AMPK .