[Effects of glutamine combined with ulinastatin on inflammatory response of patients with severe burn injury].

OBJECTIVE: To observe the effects of glutamine combined with ulinastatin on inflammatory response of patients with severe burn injury. METHODS: Sixty patients with severe burn injury admitted to our burn wards from January 2010 to December 2011 conforming to the study criteria were divided into control group (C, n = 20), glutamine group (G, n = 20), and glutamine combined with ulinastatin group (G + U, n = 20) according to the random number table. Another 10 healthy volunteers were chosen as normal control group (NC). Isonitrogenous and isocaloric nutrition supports were given to patients in groups C, G, and G + U from post burn day (PBD) 2. 0.3 g/kg protein in the form of glutamine dipeptide was given to patients in group G for 10 days. 0.3 g/kg protein was given to patients in group G + U for 10 days with the same amount of glutamine dipeptide as that in group G, followed by intravenous injection of 100 kU ulinastatin (once per 8 hours) for 7 days during 10 days. The nitrogen concentration of 24 h urine was determined with Kieldahl nitrogen determination method, and nitrogen balance was calculated one day before treatment and ten days after treatment. Meanwhile, the levels of D-lactate in serum was determined by colorimetric method, the levels of diamine oxidase (DAO), TNF-α, and IL-6 by enzyme-linked immunosorbent assay, and LPS level by kinetic turbidimetric assay with TAL. Above-mentioned indexes were also examined in group NC. The wound healing rate on PBD 30, total hospital stay days, and the incidence of burn sepsis of all burn patients were recorded. Data were processed with one-way analysis of variance, LSD test, t test, and chi-square test. RESULTS: Compared with that in group C [(-5.40 ± 1.67) g/d], nitrogen balance in group G was significantly increased ten days after treatment [(-1.35 ± 0.59) g/d, P < 0.01]. The serum levels of D-lactate, DAO, LPS, TNF-α, and IL-6 in group G ten days after treatment were significantly lower than those in group C (P < 0.05 or P < 0.01). No statistically significant difference was observed in nitrogen balance and the serum levels of D-lactate, DAO between group G + U and group G (P values all above 0.05). The serum levels of LPS, TNF-α, and IL-6 in group G + U ten days after treatment were respectively (0.167 ± 0.064) EU/mL, (43 ± 14) pg/mL, (139 ± 23) pg/mL, which were significantly lower than those in group G [(0.240 ± 0.079) EU/mL, (59 ± 8) pg/mL, (195 ± 31) pg/mL, respectively, P < 0.05 or P < 0.01]. The would healing rate on PBD 30 and total hospital stay days in group G were respectively higher and shorter than those in group C (P values all below 0.01), but no statistically significant difference in the incidence of burn sepsis was found between them (P > 0.05). The would healing rate on PBD 30 in group G+U [(96 ± 4)%] was enhanced, and total hospital stay days [(41 ± 4) d] were lowered than those in group G [(88 ± 7)%, (49 ± 5)d, P values all below 0.01]. The incidence of burn sepsis of patients in group G + U (5%) was significantly lower than that in group C (35%, χ(2) = 6.234, P < 0.05). CONCLUSIONS: Glutamine combined with ulinastatin treatment can alleviate damage to intestine after severe burn injury, lower the serum level of inflammatory cytokines, promote wound healing, and reduce the incidence of burn sepsis.

[Experimental study on the antagonistic activity of cationic multi-peptide mastoparan-1 against lipopolysaccharide].

OBJECTIVE: To explore the mechanism of cationic multi-peptide mastoparan-1 (MP-1) on the protection of mice from lipopolysaccharide (LPS) challenge. METHODS: Thirty Kunming mice were divided randomly into MP-1, injury, protection groups with 10 mice in each group. The mice in MP-1 group were injected with 3 mg/kg MP-1 by tail vein, while those in injury group were injected with 20 mg/kg LPS by tail vein, and those in protection group 3 mg/kg MP-1 within 20 seconds after 20 mg/kg LPS injection were injected. The effects of MP-1 on the protection of mice from LPS challenge were observed. In vitro, the affinity of MP-1 and PMB to LPS was compared by biosensor and FAST fit construct and expressed as Kd. And the neutralizing activity of MP-1 and PMB in dose of 5, 10, 20, 40 micromol/L on LPS (2 microg/L) was detected by dynamic turbidimetric limulus test with LPS neutralizing 0 micromol/L MP-1 and PMB as control. The mRNA expression levels of TLR4, TNF-alpha and IL-6 in murine peritoneal macrophages (PM phi) after exposure to LPS (100 ng/ml) were assayed by RT-PCR. RESULTS: MP-1 could significantly protect mice from LPS challenging with protection rate of 90%. In vitro, MP-1 had a high affinity (Kd value: 484.0 nmol/L) and neutralizing ability with LPS, but it was lower than that of PMB (Kd value: 18.9 nmol/L). The neutralizing effect of 20 and 40 micromol/L MP-1 was obviously stronger than that in 0 micromol/L (P < 0.01). MP could obviously inhibit the expression of TLR4, TNF-alpha and IL-6 mRNA in LPS-stimulated murine PM phi. CONCLUSION: MP-1 can evidently protect mice from lethal LPS challenge, and the mechanism might be related to the activity of MP-1 which binding and neutralizing LPS, blocking the combination LPS with its receptors. So the murine macrophage activation induced by LPS was inhibited.