Inhibition of mineralocorticoid receptor activation by eplerenone to reduce autophagy in obstructive nephropathy / 中国药理学通报

Aim To observe the effect of mineralocorticoid receptor blocker eplerenone on autophagy in obstructive nephropathy and its mechanism. Methods Totally 36 male Wistar rats were randomly divided into sham-operation group, model group and eplerenone group. The animal models were established with unilarteral urteral obstruction ( UUO). The rats in eplerenone group were treated with eplerenone (100 mg • kg"1 • d"1). The obstructed kidneys were collected lOd after UUO. The expression of NR3C2 was detected by laser confocal microscopy, the expression of serum and glucocorticoid-induced protein kinase 1 ( SGK-1), phosphorylated mammal target of rapamycin (p-mTOR) , autophagy associated gene 5 (Atg5) , Be-clin-1 and microtubular-associated protein 1 light chain 3 (LC3) were detected by immunohistochemistry and Western blot. Results The expression of NR3C2 was detected in cytoplasm of renal tubular distal epithelial cells, but not in nucleus in sham-operation group with laser confocal microscopy. The expression of NR3C2 was enhanced significantly in model group, mainly in nucleus but significantly inhibited in eplerenone group. The immunohistochemistry and Western blot showed that the expressions of SGK-1, Atg5, Beclin-1 and the ratio of LC3 11/I in model group were up-regulated and down-regulated by eplerenone treated group. The expression of p-mTOR was down-regulated in model group compared with sham-operation group and up-regulated in eplerenone group. Conclusions Eplerenone plays a role in reducing autophagy in obstructive nephropathy via inhibiting the activation of mineralocorti-coid receptor.

Improvement for the construction of renal interstitial fibrosis model with unilateral ureteral obstruction in rats / 中国组织工程研究

BACKGROUND: Unilateral ureteral obstruction (UUO) is a traditional surgical method that can cause renal interstitial fibrosis in rats in a short period of time (1-2 weeks), but it can develop many postoperative complications and result in a high mortality. OBJECTIVE: To optimize and improve the UUO operation in rats for reducing the incidence of postoperative complications and improving the survival rate of animals, and to detect the pathophysiological indicators of rats modeled by UUO, providing background data for the basic research on functional pharmacology. METHODS: Twenty male Sprague-Dawley rats were randomly divided into four groups, followed by traditional UUO ligation, improved UUO ligation, undissociated ureteral ligation, and opening the abdominal cavity with no ureter ligation (sham group), respectively. At 14 days postoperatively, the successful rate of renal interstitial fibrosis model, mortality rate, and the incidence of postoperative complications were compared between groups. Another 28 Sprague-Dawley rats, half male and half female, were randomly divided into improved UUO group and control group. Physiological indexes, including urine analysis, blood cells analysis, blood biochemical analysis, were tested as background information. Besides, the pathological changes of kidney tissues were compared between groups using hematoxylin-eosin staining and Masson staining at 14 and 21 days postoperatively. RESULTS AND CONCLUSION: Compared with the undissociated ureteral ligation group, the successful rate of modeling was higher in the traditional and improved UUO groups. The improved UUO surgery with double ligation of the middle ureter and no cutting of the middle ureter was characterized by easier operation, smaller surgical wound, faster modeling and higher successful rate of renal interstitial fibrosis model, lower postoperative mortality and lower incidence of complications in animals as compared with the traditional UUO surgery. The improved UUO group showed statistically significant differences from the sham group in blood biochemical indexes such as urea nitrogen, glutamate aminotransferase, and albumin (P < 0.05). Results from hematoxylin-eosin staining and Masson staining of the obstructed kidney revealed typical pathological features of renal interstitial fibrosis.

Physiology and pathophysiology of cyclooxygenase-2 and prostaglandin E2 in the kidney

The cyclooxygenase (COX) enzyme system is the major pathway catalyzing the conversion of arachidonic acid into prostaglandins (PGs). PGs are lipid mediators implicated in a variety of physiological and pathophysiological processes in the kidney, including renal hemodynamics, body water and sodium balance, and the inflammatory injury characteristic in multiple renal diseases. Since the beginning of 1990s, it has been confirmed that COX exists in 2 isoforms, referred to as COX-1 and COX-2. Even though the 2 enzymes are similar in size and structure, COX-1 and COX-2 are regulated by different systems and have different functional roles. This review summarizes the current data on renal expression of the 2 COX isoforms and highlights mainly the role of COX-2 and PGE2 in several physiological and pathophysiological processes in the kidney.

Renal tubular acidosis inducede ffects in the process of renal interstitialfibrosis / 中国医师杂志

Objective Study of renal tubular acidosis induced effects in the process of renal interstitial fibrosis .Methods Twenty rats in the sham operation group , the experimental group UUO40 only, Screening of renal tubular acidosis group , After opera-tion 7, 14, 21, 28 days, the rats were killed in batches, kidney function , organization and determination of integrin linked kinase in renal tissue immunohistochemistry and Western blot ( ILK ) expression were detected .Results UUO +RTA group than in UUO group, under the light microscope , inflammatory cell infiltration and interstitial fibrosis were more serious; Protein expression in control group only a small amount of ILK protein ,Almost no FN protein deposition ,Deposition of UUO expression of group ILK and FN proteins increased,and UUO+RTA group was more than UUO group .Conclusions In obstructive nephropathy , renal tubular acidosis can be deposited and expression of FN and up -regulation of ILK protein .

Expression of periostin in the kidneys of rats with obstructive nephropathy and its significance / 中华肾脏病杂志

Objective To investigate the expression of periostin in the kidneys of rats with obstructive nephropathy and its relevance to renal interstitial fibrosis.Methods Eighteen male adult SD rats were randomly divided into sham group,model group and benazepril group (6 in each group).Unilateral ureteral obstruction (UUO) model was induced by ligating the left ureter of rats.RT-PCR was used to detect the mRNA expressions of periostin and TGF-β1,and ELISA to detect the protein expression of periostin,Ang Ⅱ,and TGF-β1 in kidney tissue.Pathological changes of renal tissue were observed by HE and Masson staining.The protein expression of collagen Ⅰ (Col Ⅰ ) in kidney tissue was examined by immunohistochemical staining.Results The mRNA expressions of periostin and TGF-β1 in model group increased markedly as compared with sham group (all P＜0.05),and benazepril could decrease these mRNA expressions (all P＜0.05).The protein expressions of periostin,Ang Ⅱ and TGF-β1 in kidney tissue were significantly increased in model group as compared with sham group (all P＜0.05),and benazepril could decrease these protein expressions (all P＜0.05).The expression of periostin in kidney tissue was positively correlated with the expressions of Ang Ⅱ,TGF-β1 and Col Ⅰ,as well as the degree of renal interstitial fibrosis (r=0.652,0.781,0.776 and 0.825 respectively,all P ＜0.05).Conclusion Periostin expression is up-regulated in kidney tissue of rats with obstructive nephropathy,which is associated to the over-deposition of extracellular matrix (ECM) in the kidneys of UUO rats.

The risk factor analysis of obstructive nephropathy progression / 中国实用内科杂志

Objective To discuss the risk factors of the chronic obstructive nephropathy progression.Methods A retrospective analysis of the patients with chronic obstroctive nephropathy was performed.Multivariate logistic regression was used to identify correlate risk factors of the chronic obstructive nephrupathy progression.All calculation were compu- ted with the aid of SPSS 10.0 software package.Results In the analysis of risk factors of the chronic obstructive ne- phropathy progression,gender(OR=1.963,P=0.018),hypertention(OR=2.228,P=0.039),hyperuricemia (OR=4.204,P=0.000),hypocalcemia(OR=2.612,P=0.031),proteinuric(OR=1.639,P=0.049),hy- poabumia(OR=5.505,P=0.000),SIRS(OR=6.113,P=0.000),anemia(OR=5.257,P=0.000),renal atophy(OR=5.964,P=0.009),contrast medium(OR=6.113,P

The Role of Renin-Angiotensin System in Experimental Unilateral Ureteral Obstruction / 대한신장학회잡지

In order to evaluate the renal expression of renin, TGF-beta, TNF-alpha, IL-6, MCP-1, endothelin-1, osteopontin, and the role of renin-angiotensin system(RAS) in renal injury mechanism of experimental unilateral ureteral obstruction(UUO), 44 male Sprague-Dawley rats weighing 260-280g underwent sham operation(n= 8), UUO without treatment(n=12), UUO with angiotensin converting enzyme inhibitor(ACEI, enalapril 100 mg/kg body weight in drinking water, n=12) and UUO with angiotensin II AT1 receptor antagonist(AT1 RA, losartan 300mg/Kg body weight in drinking water, n= 12) under thiopental sodium anesthesia(50mg/kg, body weight, I.P.). Half number of each group was sacrificed at 3 and 7 days after surgery. With standard point count method, we evaluated the magnitude of tubulointerstitial mononuclear cell infiltration and relative volume of interstitium by light microscopic examination (PAS stain and immunohistochemistry for ED-1). Competitive RT-PCR was performed for the estimation of renin, TGF-beta, TNF-alpha, IL-6, MCP-1, endothelin-1, osteopontin and beta-actin gene expression levels of the kidneys. Renal gene expressions of renin, TGF-beta, MCP-1, TNF-alpha, IL-6, endothelin-1, and osteopontin of untreated control UUO rats were significantly increased compared to sham operated rats at 3 and 7 days after surgery. The level of TGF-beta, TNF-alpha, IL-6 and endothelin-1 gene expressions of ACEI treated UUO rats was significantly lower than those of untreated control UUO rats. AT1 RA treated UUO rats also showed significantly lower level of TGF-beta and osteopontin gene expression than those of control UUO group. Untreated control UUO rats showed significantly increased mononuclear cell infiltration of tubulointerstitium and relative volume of interstitium of the kidney compared to sham operated rats. ACEI or AT1 RA treated UUO rats showed significantly less relative volume of interstitium and mononuclear cell infiltration than those of untreated UUO rats(p<0.05, p<0.05). With the above result, we speculate that the upregulation of renin, TGF-beta, MCP-1, TNF-alpha, IL-6, osteopontin and endothelin-1 genes is closely related to the progressive renal injury process in this model and at least in part, the early activation of renin angiotensin system of the kidney is involved in this mechanism.

Localization of Smad 2, 3, 6, 7 and their changes of expression in experimental interstitial fibrosis model in rats / 中华肾脏病杂志

Objective To investigate the localization of Smad protein 2, 3, 6, 7 and their changes of expression in experimental interstitial fibrosis model in rats. Methods Thirty-six rats were divided into normal control, sham operation, and unilateral ureteral obstruction(UUO) groups, and were sacrificed at postoperative day 3, 7, 14, 21. The level of TGF-?1 mRNA was examined by RT-PCR. The sites and levels of expression of Smad protein 2, 3, 6, 7 were examined by immunohistochemistry staining and Western blot . Renal fibrosis was assessed by measuring tissue hydroxyproline. Results Compared to sham operation group, TGF-?1 mRNA was significantly increased in UUO rats, and this trend was positively correlated to increased hydroxyproline content. Immunohistochemistry staining studies indicated that Smad protein 2, 3 mainly expressed in renal tubular cells, rarely in glomeruli, and Smad protein 6, 7 were presented in both the glomeruli and proximal renal tubular cells. Expression of the Smad protein 2, 3 were significantly increased from day 3 to 21 after UUO, while the Smad protein 6, 7 were significantly reduced in the obstructive kidney. Conclusions TGF-?1/Smad signaling is involved in the progression of renal tubulointerstitial fibrosis. The absence of up-regulation of these anti-Smads proteins may be the major cause of the interstitial fibrosis in this model.

Protective effect of rosiglitazone on rat kidney after unilateral ureteral obstruction / 中华肾脏病杂志

Objective To investigate the effect of rosiglitazone on the expr es sion of PPAR?,TGF-a1 and PCNA and its mechanism on renal interstitial fibrosi s following unilateral ureteral obstruction(UUO) in rat kidney. Methods Thirty r ats were randomly assigned to shame operation group(sham group),UUO group, rosig litazone(5 mg穔g-1?d-1) treatment group after UUO. Immunohistochemistry,RT-PCR,Western blotting were performed to investigate renal pathological changes an d examine the expression of PPAR?,TGF-a1,PCNA on the 7th and 14th day in the kidney. Results In comparison with the shame group,the expression of PPAR?,TGF-a1,PCNA of UUO and treatment groups increased significantly(P

Astragalus and Angelica mixture ameliorates renal interstitial fibrosis by a multiple manner / 中国药理学通报

Aim The mixture of Chinese herbs,Astragalus & Angelica(A&A) has been found that has antifibrotic effect in rats.Methods To elucidate themechanisms underlying the renoprotective effects of A&A in the process of renal interstitial fibrosis,we investigated the pathology changes of kidneys in unilateral ureteral obstruction(UUO) rats.In the study,Wistar rats were randomly divided into CON,Sham,UUO and UUA(UUO+A&A) groups.After administration of A&A(12 g?kg?d~(-1)) for 0,3,7 and 10 d,renal damage including interstitial cell infiltration,tubular atrophy and interstitial fibrosis were quantified on HE and Masson stained tissue sections.The expression of ?-smooth muscle actin(?-SMA),transforming growth factor-?_1(TGF-?_1) and fibronectin(FN) was measured using computer image analysis of immunohistochemistry staining sections,ELISA and Western Blot.Results Renal damage and the expression of ?-SMA,TGF-?_1 and FN were all significantly exacerbated in UUO group compared with those of Sham group(P

Effects of glycyrrhizin-18? on expressions of CTGF and TGF-?1 in renal interstitium in rats with obstructive nephropathy / 第三军医大学学报

Objective To investigate the effects of glycyrrhizin-18? on the expressions of connective tissue growth factor (CTGF) and transforming growth factor-?1 (TGF-?1) in renal interstitium in rats with obstructive nephropathy. Methods A total of 100 Wistar rats were divided into experiment group (include prophylaxis group with glycyrrhizin-18?, glycyrrhizin-18? treatment group, and group with normal saline) and control group (sham operation group). Models of rats with obstructive nephropathy were established by unilateral ureteral ligation. The rats were sacrificed at 7, 14, 28, and 56 d after operation and specimens were taken from the renal cortex. The morphopathological changes in the renal interstitium were observed byr light and electron microscopy. CTGF, TGF-?1, and collagen type Ⅲ were detected by immunohistochemical staining. The measured data were evaluated by EIG image analysis system. Results In the renal interstitium, there was progressive fibrosis in the model. Semi-quantitative analysis indicated that the expression levels of CTGF, TGF-?1, and collagen type Ⅲ in the renal interstitium in glycyrrhizin-18? treatment and prophylaxis groups were markedly higher than those in the sham operation group (P0.05). The expression of CTGF in the renal interstitium was closely correlated with those of TGF-?1 and collagen type Ⅲ (P