[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.

In vitro and in vivo haemolytic studies of tentacle-only extract from jellyfish Cyanea capillata.

To approach the real haemolytic process of jellyfish toxins, both in vitro and in vivo haemolysis of tentacle-only extract (TOE) from jellyfish Cyanea capillata has been studied. Dose-response curves of the haemolytic activity of TOE in vitro were sigmoid shaped in both erythrocyte suspension and diluted whole blood, with the former more sensitive to TOE. The in vivo haemolysis increased sharply in the first 10 min and was followed by a gradual increase in the following 3h, with increasing blood potassium and lactic acid accordingly. SC5b-9 complexes were significantly up-regulated in vitro, but not in vivo. These results showed that the haemolysis of TOE in diluted whole blood and in vivo is not totally consistent with that in the erythrocyte suspension, and blood plasma might play a protective role against haemolysis. Thus we suggested that erythrocyte suspension can be used to test the damage of toxin on erythrocyte membrane, while the diluted whole blood may be more suitable to test the haemolysis of toxins.

The lethality of tentacle-only extract from jellyfish Cyanea capillata is primarily attributed to cardiotoxicity in anaesthetized SD rats.

Previous studies in our laboratory have shown that tentacle-only extract (TOE) has similar hypotensive effects with nematocyst venom from jellyfish Cyanea capillata, and the experimental studies on the in vivo cardiovascular effects of TOE were further performed to explore the leading cause of death and analyze the basic physiopathologic change in anaesthztized SD rats. Plots of TOE dose versus time to death showed dose-dependent curvilinear relationship. ECG changed in a dose- and time-dependent manner. Haemodynamic parameters, including the heart rate, mean femoral arterial pressure, left ventricular developed pressure and the first derivative of left ventricular pressures, decreased, but left ventricular end-diastolic pressure did not increase. Arterial partial pressure of oxygen and oxygen saturation did not change. Lactate dehydrogenase, creatine kinase and MB isoenzyme of creatine kinase increased significantly. Histopathological examination showed congestion, haemorrhage, edema and denaturation in the heart; congestion, haemorrhage in the lung and acute congestion in the liver. Transmission electron microscopy examination found that parts of sarcomeric filaments disrupted, dissolved and disappeared, and parts of mitochondria swelled in cardiocytes. Laser scanning confocal microscope examination found that ventricular myocytes from adult rat were deformed and ultimately died within 30 min after TOE treatment. Our results reveal that cardiodepressive effect of C. capillata TOE is the leading cause of death and acute total heart failure is the basic physiopathologic change in anaesthetized SD rats.