The effects of naringenin on pancreatic fibrosis in chronic pancreatitis mouse model and activation, proliferation and apoptosis of pancreatic stellate cells / 中华胰腺病杂志

ABSTRACT

Objective:To study the effects of naringenin on pancreatic fibrosis in the mouse model of chronic pancreatitis (CP) and its effects on the activation, proliferation and apoptosis of pancreatic stellate cells (PSCs).Methods:Eighteen C57BL/6 mice were randomly divided into control group, CP group and naringenin group, with 6 mice in each group. The CP mouse model was established by intraperitoneal injections of caerulein. Naringenin group was given naringenin (200 mg/kg/day) by gavage once a day from the first day of the fourth week of modeling process to the day before the killing; the control group and CP group were treated by gavage with an equivalent amount of drug solvent containing 0.5% sodium carboxymethyl cellulose (CMC-Na). Mice were killed 5 days after the last caerulein injection, and their pancreatic tissues were collected for hematoxylin-eosin staining and Sirius Red staining, pathological scoring and collagen sedimentation detection. Naringenin with different concentrations (0, 5, 10, 20, 50, 100, 150, 200 μmol/L) were used to intervene HPSC for 24 hours, and CCK-8 method was used to detect the cell activity. TGF-β1 recombinant protein (2 ng/ml) was used to induce PSCs for 1 hour (TGF-β1 stimulation group), and naringenin with low (50 μmol/L), middle (100 μmol/L) and high (150 μmol/L) concentration was used to intervene for 36 hours after TGF-β1 stimulation, respectively. Western Blotting was used to detect the expression of PSC activation related proteins FN and COL1A1, cell proliferation marker p21, anti-apoptotic protein Bcl-xL, pro-apoptotic protein Bax and Bid.Results:The pathological scores of pancreatic tissue [(7.33±1.15), (4.67±1.15)] and the percentage of collagen positive areas [(46±4), (28±2)%] in CP group and naringenin group were higher than those in the control group [0, (4±2)%]. However, these indexes in the naringenin group were lower than those in CP group, and the differences were all statistically significant (all P value <0.05). The relative expression of FN in control group, TGF-β1 stimulation group and low, medium and high naringenin group was 0.02, 0.76, 0.67, 0.34 and 0.07, respectively; the expression of COL1A1 in these groups was 0.51, 1.71, 1.34, 0.84 and 0.11. The expression of FN and COL1A1 in TGF-β1 stimulation group was significantly higher than that in control group, and the expression of FN and COL1A1 in low, medium and high naringenin group was significantly lower than that in TGF-β1 stimulation group, and the differences were all statistically significant (all P value <0.05). The expression of p21 in the above five groups was 0.87, 1.18, 1.27, 1.22 and 1.00. The expression of p21 in TGF-β1 stimulation group was higher than that in control group, and the expression of p21 in high naringenin group was obviously lower than that in TGF-β1 stimulation group, and the differences were all statistically significant (all P value <0.05). In addition, the expression of Bcl-xL in these groups was 2.09, 2.21, 2.38, 2.50 and 2.12; the expression of Bax was 0.98, 0.88, 0.98, 1.00 and 0.88; the expression of Bid was 1.15, 1.09, 1.14, 1.18 and 1.18. There was no statistically significant difference among these groups (all P value >0.05). Conclusions:Naringenin could significantly alleviate the inflammation, atrophy and fibrosis in the CP mouse model, and inhibit the activation and proliferation of PSCs. However, naringenin had no significant effect on the apoptosis of PSCs, indicating that naringenin may be potentially used to treat pancreatic fibrosis in CP.