Protective effect of astragaloside Ⅳ on acute tubular injury induced by aristolochic acid I

AIM: To study the effect of astragaloside Ⅳ (AS Ⅳ) on acute aristolochic acid nephropathy (AAN). METHODS: MTT assay was used to observe the viability of human proximal tubule epithelial cell line HK-2 in vitro. In in vivoexperiments, Kunming mice were intra peritoneally injected with aristolochic acid I (AAⅠ) for 6 d to induce acute AAN model.AS Ⅳ at dose of 50 mg·kg^-1·d^-1 was gavaged for 6 d, and the levels of urine protein, urine γ-glutamyltransferase (γ-GT), serum creatinine (SCr) and blood urea nitrogen (BUN) were measured. The histological changes of the kidneys were observed under microscope by HE and periodic acid-silver methenamine (PASM) staining at the 7th day. RESULTS: The cell viability was significantly inhibited by AA I. However, the cell viability increased when AA I combined with AS Ⅳ was given as compared with control group, indicating that AS Ⅳ plays a dose-dependent protective role in HK-2 cells against the injury of AA I. The results of in vivo experiments showed that the levels of urine protein, urine γ-GT, SCr and BUN were decreased in AA I combined with AS Ⅳ group compared with AA I renal injury group. Histological study showed that AA I-induced kidney injury was improved with the decrease in the area of tubule necrosis and nude tubular basement membrane. CONCLUSION: AS Ⅳ has a protective effect on renal tubular damage induced by AA I.     

Chinese herbal preparation Qing Yi Tang Ⅱ granule protects against experimental acute pancreatitis in mice

AIM: To investigate the protect effect of Chinese herbal preparation, Qing Yi TangⅡgranule (QYT), on acute pancreatitis (AP) mice and its mechanism. METHODS: Adult male and female C57BL/6 mice (n=24) were randomly divided into control group, AP group and AP+QYT group. Severe AP was induced by combined intra-peritoneal injection of caerulein (50 μg/kg) and lipopolysaccharide (LPS; 10 mg/kg). Drinking water or 24% QYT solution was given to the mice in AP group or AP+QYT group by oral gavage. The mice in control group were intraperitoneally injected with equivalent volume of normal saline and gavaged with water. The mice were sacrificed 3 h after the last injection. Severity of AP was assessed by biochemical markers and histology. The plasma level of IL-6 and MCP-1, and lung myeloperoxidase (MPO) levels were determined for assessing the extent of systemic inflammatory response. The intestinal microflora, T lymphocytes and T-lymphocyte subgroups were examined for assessing the function of the intestinal barrier. RESULTS: Compared with control group, the mice in AP group presented significant increases in pathological histological scores, plasma amylase activity and IL-6 and MCP-1 levels, as well as the MPO activity in the lung and pancreatic tissues. QYT attenuated these changes to some extent. Furthermore, the increased intestinal microflora was significantly reversed by QYT. No difference of the numbers of Peyer's patches in small intestine in the 3 groups was observed, but the percentage of CD3⁺ T lymphocytes decreased significantly in AP group, and increased percentage of CD4⁺ and CD4⁺/CD8⁺ ratio were found in AP group and AP+QYT group. CONCLUSION: QYT protects against cearulein and LPS-induced acute pancreatitis in mice. The mechanisms may be related to the suppression of the inflammatory response, promoting intestinal bacteria removal, and regulating the functions of T lymphocytes in the intestinal barrier.     

Alteration of intracellular density is a pathological response in adrenaline-induced acute pulmonary edema in mice

AIM: To investigate the change of intracellular density as a pathological response in the lungs. METHODS: A mouse model of acute pulmonary edema (APE) was induced by overdose of adrenaline. The intracellular density alteration was determined by discontinuous sucrose gradient centrifugation of the lung homogenates. Lung wet/dry weight ratio was measured to evaluate the development of APE. Glycogen content, and the mRNA expression of IL-1β and IL-6 in the liver were quantitatively determined. RESULTS: After injection of adrenaline, change of intracellular density was observed in the lungs in a time-and dose-dependent manner, and this change was found to be significantly correlated with the lung wet/dry weight ratio. The mRNA levels of IL-1β and IL-6 in the liver significantly increased, with a peak at 1 h after injection of adrenaline. CONCLUSION: Alteration of intracellular density in the lungs is a pathological response, which can be induced by overdose of adrenaline. This pathological change could be used in the localization of tissues/cells targeted by drugs and in the study of pathogenesis in vivo.     

Relationship of p38MAPK,NF-κB and HO-1 in LPS-induced acute lung injury in rats

AIM: To investigate the relationship of p38 mitogen-activated protein kinases (p38MAPK), nuclear factor-kappa B (NF-κB) and heme oxygenase-1 (HO-1) in acute lung injury (ALI) in rats.METHODS: Forty male Wistar rats were divided into 5 groups (n=8) at random: control group or normal saline group (NS group), lipopolysaccharide group (LPS group), Hemin (inducer of HO-1)+LPS group, ZnPPIX (inhibitor of HO-1)+LPS group and SB203580 (inhibitor of p38MAPK)+LPS group (SB+LPS group). Six hours after endotracheal instillation of LPS or NS, the ratio of neutrophils and the protein contents in bronchoalveolar lavage fluid (BALF) of right lung, the ratio of wet/dry weight (W/D) of the superior lobe of right lung, and arterial blood gas analysis (ABG) were examined. The protein levels of p38MAPK and NF-κB in the lower lobe of right lung were detected by Western blotting. The protein expression of HO-1 in the middle lobe of right lung was measured by the method of immunohistochemisty. The structure of the lung was evaluated under light microscope. RESULTS: Compared with NS group, the ratio of neutrophils and protein contents in BALF, the ratio of W/D, the protein levels of HO-1, p38MAPK and NF-κB were obviously higher, and arterial oxygen pressure (PaO₂), partial pressure of carbon dioxide in artery (PaCO₂) and bicarbonate content (HCO^-₃) were significantly lower in LPS group, Hemin+LPS group, ZnPPIX+LPS group and SB+LPS group (P<0.05 or P<0.01). The ratio of neutrophils and proteins in BALF, the ratio of W/D, the protein levels of p38MAPK and NF-κB were significantly lower, the protein level of HO-1 was obviously higher in Hemin+LPS group and SB+LPS group than those in LPS group (P<0.05), while the changes of the parameters in ZnPPIX+LPS group were in a contrary manner (P<0.05). No significant difference of the parameters between Hemin+LPS group and SB+LPS group (P>0.05) was found. The structures of the lung tissues in LPS group were severely damaged and even severer damages were observed in ZnPPIX+LPS group. The structural changes of the lung tissues in Hemin+LPS group and SB+LPS group were slighter. CONCLUSION: p38MAPK/NF-κB and HO-1 are inhibited by each other and the effects of them are independent on the acute lung injury.     

Change of endogenous hydrogen sulfide/cystathionine-γ-lyase system in acute lung injury induced by LPS in rats

AIM: To observe the changes of endogenous hydrogen sulfide/cystathionine-γ-lyase (H2S/CSE) system while acute lung injury induced by LPS in rats. METHODS: Eighty rats were randomly divided into six groups (n=8): Ⅰ, control group;Ⅱ, LPS 1 h group; Ⅲ, LPS 3 h group; Ⅳ, LPS 6 h group; Ⅴ, LPS 9 h group; Ⅵ, LPS 12 h group. The ALI model of rats was prepared with LPS. The rats were respectively killed at 1, 3, 6, 9 or 12 h after administration of LPS. The morphological changes of lung tissues were observed by light and electron microscope. The lung coefficient and the wet-to-dry weight ratio were measured. The contents of IL-1β and IL-10 in serum, the H2S level in plasma and the CSE activity in lung tissue were respectively detected. RESULTS: ⑴ In LPS 1 h group, the morphology, the lung coefficient, the wet-to-dry weight ratio, the H2S level and the CSE activity showed no changes compared with the control group. The contents of IL-1β and IL-10 were increased compared with the control group (IL-1β, P<0.05;IL-10, P<0.01). ⑵ In LPS 3 h, 6 h, 9 h and 12 h groups, compared with the control group, the lung tissues were significantly damaged, the lung coefficient and the wet-to-dry weight ratio were significantly increased respectively (LPS 3 h, P<0.05; LPS 6 h, 9 h, 12 h, P<0.01). The contents of IL-1β and IL-10 in serum were markedly increased (P<0.01). The H2S level in plasma and the CSE activity in lung tissue were significantly decreased (P<0.01).CONCLUSION: The changes of inflammatory cytokines may be the pathological foundation of the ALI induced by LPS and the endogenous hydrogen sulfide/cystathionine-γ-lyase system is possibly involved in the formation of the ALI.