Effect of short-chain fatty acids on microglial synapse engulfment in aged rats with postoperative cognitive dysfunction
10.3760/cma.j.cn131073.20240322.00811
- VernacularTitle:短链脂肪酸对术后认知功能障碍老龄大鼠小胶质细胞吞噬突触的影响
- Author:
Xiang LIU
1
;
Menglin LIU
;
Xiaona TAN
;
Yaozong YU
;
Junfang NIU
;
Qiujun WANG
Author Information
1. 河北医科大学第三医院麻醉科，石家庄 050051
- Keywords:
Short-chain fatty acids;
Cognitive dysfunction;
Aged;
Neuron;
Microglia;
Engulfment of synapses
- From:
Chinese Journal of Anesthesiology
2024;44(8):958-962
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the effect of short-chain fatty acids on microglial synapse engulfment in aged rats with postoperative cognitive dysfunction (POCD).Methods:Forty-eight healthy male Sprague-Dawley rats, aged 18 months, weighing 520-650 g, were divided into 4 groups ( n=12 each) using a random number table method: control group (group C), short-chain fatty acids group (group S), POCD group (group P), and POCD+ short-chain fatty acids group (group PS). Rats received short-chain fatty acids (sodium propionate 25.9 mmol/L, sodium butyrate 40 mmol/L and sodium acetate 67.5 mmol/L) in the free drinking water for 28 days in S and PS groups. On day 29, anesthesia was induced with 4%-5% sevoflurane and maintained with 3% sevoflurane, and the tibial fracture internal fixation was performed to prepare a rat model of POCD in P group and PS group. Morris water maze test was performed at day 7 after surgery. The escape latency, times of crossing the original platform, mean swimming speed and time spent in the original platform quadrant were recorded. The rats were sacrificed at the end of Morris water maze test, and the brains were collected to analyze the number and density of dendritic spines in the hippocampal CA1 region (by Golgi staining) and to determine the expression of postsynaptic density 95 (PSD95) and complement 1q (C1q) in the hippocampal CA1 region (by immunofluorescence). Results:Compared with group C, the times of crossing the original platform were significantly decreased, the time spent in the original platform quadrant was shortened, the escape latency was prolonged, the number and density of dendritic spines and the number of intersection points between dendrites and concentric circles were decreased, the expression of PSD95 was down-regulated, and the expression of C1q was up-regulated in P and PS groups ( P<0.05). Compared with group P, the times of crossing the original platform were significantly increased, the time spent in the original platform quadrant was prolonged, the escape latency was shortened, the number and density of dendritic spines and the number of intersection points between dendrites and concentric circles were increased, the expression of PSD-95 was up-regulated, and the expression of C1q was down-regulated in group PS ( P<0.05). Conclusions:The mechanism by which short-chain fatty acids attenuates POCD is related to decreased microglial engulfment of synapses in aged rats.
