Effect of α-melanocyte stimulating hormone and its novel analogue on the production of tissue factor pathway inhibitor in mice with endotoxemia

Abstract

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. 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). The plasma TFPI levels began to increase (11.84±1.55 μg/L) in the endotoxemia mice 4 hours after LPS challenge and reached the peak (23.49 ± 1.12 μg/L) 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 group: 58.79±2.67 μg/L vs. 28.49±1.69 μg/L, STY39 group: 71.08±2.13 μg/L vs. 28.49±1.69 μg/L, 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 STY39 treatment 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 lung: 51.10±2.89 vs. 32.43±2.51, STY39 in lung: 72.11±3.48 vs. 32.43±2.51; α-MSH in liver: 43.21±2.12 vs. 29.29±2.06, STY39 in liver: 66.82±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 value: 45.21±1.80 vs. 30.44±2.23, P<0.01), but the treatment with α-MSH had no obvious effect (A value: 24.61±1.98 vs. 30.44±2.23, P>0.05). The enhancing effect of early administration of STY39 on TFPI mRNA expression in the lung, liver and kidney tissues of endotoxemia mice was more powerful than that of α-MSH (all P<0.01). 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.