Effects of magnolol on autophagy of interstitial Cajal cells and intestinal motility in acute necrotizing pancreatitis rats
10.3760/cma.j.cn115667-20240627-00114
- VernacularTitle:厚朴酚对急性坏死性胰腺炎大鼠小肠Cajal细胞自噬和小肠运动功能的影响
- Author:
Yangqin CHEN
1
;
Haowen JIANG
1
;
Wenjie QI
1
;
Bin MIAO
1
Author Information
1. 首都医科大学附属北京友谊医院感染内科，北京 100050
- Publication Type:Journal Article
- Keywords:
Pancreatitis, acute necrotizing;
Autophagy;
Intestine, small;
Magnolol;
Rats
- From:
Chinese Journal of Pancreatology
2025;25(2):119-125
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the effects of magnolol on autophagy in intestinal Cajal cells and intestinal motility in rats with acute necrotizing pancreatitis (ANP).Methods:Forty-five Wistar rats were randomly divided into three groups by a random number table: control group, ANP group and magnolol intervention group, with 15 rats in each group. The ANP model was established by intraperitoneal injection of cerulein. The magnolol intervention group received a tail vein injection of 20 μg/kg magnolol ethanol solution 30 minutes after modeling. After 12 hours, ileal tissues were collected for pathological examination and scoring. Intestinal transit rate was measured using the carbon powder propulsion method, and isolated intestinal muscle strips were prepared to assess amplitude and frequency of spontaneous contraction. Oxidative stress markers in intestinal tissues, including superoxide dismutase (SOD) activity, malondialdehyde (MDA) and nitric oxide (NO) levels, were measured using xanthine oxidase, thiobarbituric acid, and enzymatic reduction assay kits, respectively. Cajal cells were isolated from intestinal smooth muscle tissues, and the expression of autophagy-related proteins (Beclin1, LC3Ⅱ, LC3Ⅰ, p62) and p-Kit was detected by Western blot. Double immunofluorescence staining was used to trace autophagy in Cajal cells.Results:The pathological scores of ileal tissues in the control, ANP, and magnolol intervention groups were (0.33±0.52), (4.83±0.41), and (3.50±0.55), respectively. The score in ANP group was significantly higher than that in the control group, while the score in the magnolol intervention group was lower than that in the ANP group, with statistically significant differences (all P value <0.05). Intestinal transit rate, amplitude and frequency of spontaneous contraction in the ANP group were significantly slower than those in the control group, while these parameters in the magnolol intervention group were significantly improved compared to the ANP group, with statistically significant differences (all P value <0.05). SOD activity in the control, ANP, and magnolol intervention groups were (73.8±8.1), (42.8±7.2), and (71.2±10.4) N/mg prot, respectively; NO levels were (1.72±0.26), (3.19±0.43), and (1.94±0.23) μmol/g prot; and MDA levels were (1.15±0.38), (3.84±0.30), and (1.68±0.33) nmol/mg prot. SOD activity in the ANP group was significantly lower than that in the control group, while NO and MDA contents were significantly higher. In the magnolol intervention group, SOD activity was significantly higher, and NO and MDA contents were significantly lower than those in the ANP group, with statistically significant differences (all P value <0.01). The levels of Beclin1, LC3Ⅱ/Ⅰ ratio, and p-Kit in the intestinal Cajal cells of ANP group were significantly higher than those in the intestinal Cajal cells of control group, while the p62 level was significantly lower. In the intestinal Cajal cells of magnolol intervention group, the levels of Beclin1, LC3Ⅱ/Ⅰ ratio, and p-Kit were significantly lower while the p62 level was significantly higher than those in the intestinal Cajal cells of ANP group, with statistically significant differences (all P value <0.01). The numbers of c-Kit/GFP-LC3 double-positive Cajal cells in the control group, ANP group, and magnolol intervention group were (9.59±5.06), (11.27±8.30), and (10.27±6.30), respectively. The ANP group had significantly more double-positive cells than the control group, while the magnolol intervention group had significantly less double-positive cells than the ANP group, with statistically significant differences (all P value <0.05). Conclusions:Excessive oxidative stress and autophagy in Cajal cells are important mechanisms underlying ANP-induced intestinal motility dysfunction. Magnolol can improve intestinal motility in ANP by antagonizing oxidative stress and reducing autophagy in Cajal cells. p-Kit may play a regulatory role in this process.
