Effect of α-melanocyte stimulating hormone and its novel analogue on the production of tissue factor pathway inhibitor in mice with endotoxemia / 中华危重病急救医学

ABSTRACT

Objective To evaluate the effect of α-melanocyte stimulating hormone (α-MSH) and its novel analogue STY39 on the production of tissue factor pathway inhibitor (TFPI) in mice with endotoxemia.Methods Female BALB/c mice were randomly divided into eight groups with 9 mice in each group.Endotoxemia was reproduced by intraperitoneal injection of lipopolysaccharide (LPS,25 μg/kg) and D-galactosamine (D-Gal,100 mg/kg).The animals of the control group were given phosphate buffered solution (PBS) instead.In the experimental groups,the mice were injected intraperitoneally with 2.5 mg/kg α-MSH or STY39 at 1,2 or 3 hours following LPS injection.The orbital blood was collected at different time points,and tissues of lung,liver,and kidney were collected 8 hours after the administration of LPS.The plasma TFPI levels were determined by enzyme linked immunosorbent assay (ELISA),and the expression of TFPI mRNA in different tissues was determined with reverse transcription-polymerase chain reaction (RT-PCR).Results The plasma TFPI levels (μg/L) began to increase (11.84 ± 1.55) in the endotoxemia mice 4 hours after LPS challenge and reached the peak (23.49 ± 1.12) at 8 hours.α-MSH or STY39 treatment at 1,2 or 3 hours after LPS challenge could significantly increase the TFPI content,with the best drug effect at 1 hour after LPS challenge (the blood was collected 8 hours after LPS challenge,α-MSH group58.79 ± 2.67 vs.28.49 ± 1.69,STY39 group71.08 ± 2.13 vs.28.49 ± 1.69,both P＜0.01),and the effect of STY39 was better than that of α-MSH (P＜0.01).A small amount of TFPI mRNA expression was observed in each tissue of the healthy mice.After LPS challenge,TFPI mRNA expression was increased in all the tissues,especially in the lung,liver and kidney.α-MSH or STY39treatment at 1 hour after LPS challenge could significantly up-regulate the expression of TFPI mRNA in the lung and liver (A value,α-MSH in lung51.10 ±2.89 vs.32.43 ±2.51,STY39 in lung72.11 ±3.48 vs.32.43 ±2.51;α-MSH in liver43.21 ± 2.12 vs.29.29 ± 2.06,STY39 in liver66.82 ± 1.76 vs.29.29 ± 2.06,both P＜0.01).The treatment with STY39 at 1 hour after LPS challenge could significantly up-regulate the expression of TFPI mRNA in the kidney (A value45.21 ± 1.80 vs.30.44 ± 2.23,P＜0.01),but the treatment with α-MSH had no obvious effect (A value24.61 ± 1.98 vs.30.44 ± 2.23,P＞0.05).The enhancing effect of early administration of STY39 on TTPI mRNA expression in the lung,liver and kidney tissues of endotoxemia mice was more powerful than that of α-MSH (all P＜0.01).Conclusion The early administration of α-MSH or STY39 may up-regulate TFPI production in the mice with endotoxemia,and the effect of STY39 is superior to α-MSH.