[Effects of Chinese herbal medicine Dusuqing Granule on toll-like receptor 4 signaling in multiple organ injury induced by bacterial pneumonia in aged rats].

OBJECTIVE: To study the protective mechanism of Dusuqing Granule, a compound Chinese herbal medicine, on the senile multiple organ injury caused by bacterial pneumonia by observing the expression changes of molecules related to toll-like receptor 4 (TLR4) signaling. METHODS: A total of 55 male Sprague-Dawley aged rats were divided into control group, untreated group, Dusuqing group and lomefloxacin group. There were 25 rats in the untreated group and 10 rats in each of the other three groups. Multiple organ injury in a rat model of pneumonia was induced by injection of Klebsiella pneumoniae through tracheal intubation. By means of immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR), examinations were made on mRNA expressions of lipopolysaccharide-binding protein (LBP), CD14, TLR4 and interleukin-1 receptor-associated kinase-1 (IRAK-1) in the tissues of the lung, heart and small intestine, and also on the protein expressions of TLR4, tumor necrosis factor receptor-associated factor 6 (TRAF6) and nuclear factor-κB (NF-κB). RESULTS: Expressions of LBP, CD14, TLR4 and IRAK-1 mRNAs in the tissues of the lung, heart and small intestine in the untreated group were stronger than those in the control group (P<0.01 or Plt;0.05). The protein expressions of TLR4, TRAF6 and NF-κB were increased dramatically in the untreated group as compared with the control group (Plt;0.01 or Plt;0.05). Compared with the untreated group, the expressions of LBP, CD14, TLR4 and IRAK-1 mRNAs in the tissues of the lung, heart and small intestine in the Dusuqing group were weakened significantly (Plt;0.01 or Plt;0.05). Meanwhile, the protein expressions of TLR4, TRAF6 and NF-κB were decreased markedly in the Dusuqing group (Plt;0.01 or Plt;0.05). CONCLUSION: Dusuqing Granule is effective in suppressing toll-like receptor signal transduction activation and reducing the secretion of cytokines and inflammatory mediators, which can further reduce the organ tissue injury. Dusuqing Granule can decrease the levels of TLR signal transduction activation including the targets LBP, CD-14, TLR4, IRAK-1, TRAF6 and NF-κB, which is different from the special inhibitor that acts only on some segments.

Caspase-3 inhibitor prevents apoptosis of human islets immediately after isolation and improves islet graft function.

OBJECTIVES: Apoptosis appears in islets after isolation, and it has a detrimental effect on the islet function. To improve the outcome of clinical islet transplantation, it is crucial to protect islets from apoptosis. The aim of this study was to determine whether a caspase-3 inhibitor (Z-DEVD-FMK) added to culture media protects islets from apoptosis and to compare the effects of fetal bovine serum (FBS) with human serum albumin (HSA) as a protein supplement in culture. METHODS: Isolated human islets were cultured under 4 different conditions: 0.5% HSA (control), 0.5% HSA + 25 micromol/L Z-DEVD-FMK, 0.5% HSA + 100 micromol/L Z-DEVD-FMK and 10% FBS for 2 days. Next, 1000 IEQ islets precultured with 0.5% HSA and with or without 100 micromol/L Z-DEVD-FMK were transplanted to diabetic nude mice. RESULTS: The islet yields were higher in Z-DEVD-FMK-treated groups, and the inhibitor prevented apoptosis dose dependently. The yield and insulin release were higher in FBS-treated group than in the control group, but FBS did not affect apoptosis. All 6 mice transplanted with islets pretreated with Z-DEVD-FMK, and 3 of 8 mice with control islets became normoglycemic posttransplantation. CONCLUSION: Z-DEVD-FMK prevented apoptosis of isolated human islets and improved its function. FBS (10%) improved the islet yield and insulin secretion more than 0.5% HSA.