[Effect of Huayu Jiedu Recipe on the Expressions of NLRP3, Caspasel, and IL-1 ß in Kidneys of Obstructive Nephropathy Rats].

Objective To observe the effect of Huayu Jiedu Recipe (HJR) on the expressions of nucleotide-binding oligomerization domain (NOD)-like receptor protein 3 (NLRP3) , Caspase-1 , IL-1 ß in kidneys of obstructive nephropathy rats. Methods Totally 40 clean grade SD rats were randomly divided into the sham-operation group (n =10) and the model group (n =30). The model of obstructive nephropa- thy was established by unilateral ureteral obstruction (UUO). Totally 30 successfully modeled UUO rats were randomly divided into the model group, the Western medicine group, the Chinese medicine group, 10 in each group. Eplerenone (100 mg . kg ⁻¹ . d⁻¹) was administrated to rats in the Western medicine group. HJR (13.7 g . kg ⁻¹ . d⁻¹) was administrated to rats in the Chinese medicine group. Equal volume of normal saline was administered to rats in the sham-operation group and the model group. All medica- tion was performed once daily for 10 successive days. The serum IL-1 ß level was detected. Protein and mRNA expressions of NLRP3, Caspase-1, and IL-1 ß in renal tissue were detected. TUNEL positive rate was detected by TUNEL method. Results The expression of NLRP3 was not obviously seen, Caspase-1 and IL-1 ß were weakly expressed, and only fewer amount of TUNEL positive cells could be seen in the sham-operation group. Compared with the sham-operation group, serum IL-1ß level increased (P < 0. 01) , mRNA and protein expression of NLRP3, Caspase-1 , and IL-1 ß were up-regulated in renal tissue of the model group (P <0. 01). NLRP3 was mainly expressed in renal interstitial macrophages and renal tubular epithelial cells. Caspase-1 and IL-1 ß were mainly expressed in the cytoplasm of renal tubular epithelial cells. TUNEL positive cells were significantly increased, mainly dominated in interstitial expanded epithelial cells of distal tubules (P <0. 01). Compared with the model group, serum IL-1 ß level was significantly decreased (P <0. 01) ; mRNA and protein expressions of NLRP3, Caspase-1 , and IL- ß were obviously down-regulated (P <0. 01) , and the TUNEL positive rate was obviously decreased (P <0. 05, P < 0. 01) in the two medicated groups. Conclusion HJR could down-regulate mRNA and protein expres- sions of NLRP3, Caspase-1 , and IL-1ß, thus attenuating inflammatory injury of renal tissue.

[Effect of shenluotong decoction on renal interstitial fibrosis in rats with obstructive nephropathy].

OBJECTIVE: To observe the effect of Shenluotong Decoction (SD) on serum levels of aldosterone, monocyte chemoattractant protein-1 (MCP-1), α-smooth muscle protein (α-SMA), and nuclear factor-KB (NF-κB) in obstructive nephropathy rats, and to explore the initial mechanism of SD for inhibiting renal interstitial fibrosis. METHODS: Totally 48 healthy Wistar rats were randomly divided into the sham-operation group (n =12) and the model group (n =36). Renal interstitial fibrosis rat model was established by unilateral ureteral obstruction (UUO). After successful modeling, 36 rats were randomly divided into the model group, the Chinese medicine group, and the Western medicine group, 12 in each group. Eplerenone was added in the forage at the daily dose of 100 mg/kg for rats in the Western medicine group. Chinese medicine was added in the forage at the daily dose of 26 g/kg for rats in the Chinese medicine group. Equal volume of normal saline was administered to rats in the sham-operation group and the model group. All medication was performed once daily. The obstructive kidneys were extracted ten days after medication. The pathomorphological changes were observed. The contents of serum aldosterone and MCP-1, and the protein or mRNA expression of MCP-1, α-SMA, and NF-KB were detected. RESULTS: Compared with the sham-operation group, infiltration of a large amount of inflammatory cells and collagen deposition significantly increased, serum contents of aldosterone and MCP-1 obviously increased (P < 0.01), the expression of MCP-1 mRNA and protein were significantly up-regulated (P <0.01), the protein expression of α-SMA and NF-KB were significantly enhanced in the model group (P <0.01). Com- pared with the model group, infiltration of inflammatory cells and renal collagen deposition were attenua- ted in the Chinese medicine group and the Western medicine group, the serum MCP-1 level were reduced, and the mRNA and protein expression of MCP-1 were significantly down-regulated (P <0.01), the protein expression of α-SMA and NF-KB were obviously inhibited (P <0. 01). At the same time, serum aldosterone level was reduced in the Chinese medicine group (P <0.01). CONCLUSIONS: inflammatory lesions of the renal tissue could promote the progress of interstitial fibrosis in rats with obstructive nephropathy. SD could attenuate interstitial fibrosis through reducing serum contents of aldosterone and MCP-1, down-regulating MCP-1/ NF-KB, and inhibiting the expression of α-SMA.

Chronic intermittent hypoxia induces renal fibrosis through MR activation.

Obstructive sleep apnea syndrome (OSAS) is a disorder characterized by recurrent arousal from sleep and chronic intermittent hypoxia (CIH). OSAS-associated chronic kidney disease is mainly caused by CIH-induced tissue damage. Therefore, an OSAS model was established by CIH exposure in a hypoxic chamber for five weeks. In our study, macrophage infiltration and macrophage-myofibroblast transition (MMT) were observed in the kidneys of CIH rats and appeared to contribute to the development of renal fibrosis. However, the underlying mechanisms are not well defined. We also found that upon binding to the mineralocorticoid receptor (MR), aldosterone stimulated MMT and consequently led to renal fibrosis under hypoxic conditions. Additionally, an in vitro study of RAW264.7 macrophages demonstrated that MR activation may contribute to MMT, which resulted in a predominant M1 phenotype under hypoxic conditions. These effects were reversed by the MR blocker eplerenone. These results provide preliminary evidence that MR activation might be involved in the transdifferentiation of macrophages into myofibroblasts in the CIH model. The attenuation of renal injury demonstrates a protective role of MR blockade in CIH-induced renal disease.

The Inhibitory Effect of Eplerenone on Cell Proliferation in the Contralateral Kidneys of Rats with Unilateral Ureteral Obstruction.

BACKGROUND: The unilateral ureteral obstruction (UUO) model not only induces renal interstitial fibrosis in the obstructed kidney but also induces injury in the contralateral kidney. We hypothesized that activation of the mineralocorticoid receptor (MR) may induce fibrosis in the early stage of UUO. METHODS: Thirty male Sprague-Dawley rats weighting 200 ± 10 g were used in this study and randomly divided into 3 groups: a UUO group, a UUO and eplerenone group, and a sham group. The contralateral kidney and plasma were harvested for further study 10 days after surgery. RESULTS: The level of plasma aldosterone (869.95 ± 55.851 pg/mL) was significantly higher in the UUO group than that in the sham group (478.581 ± 36.186 pg/mL vs. UUO, p < 0.05). The infiltrated inflammatory cells (F4/80) and deposited collagens were increased significantly in the contralateral kidneys in the UUO group compared to those in the sham group, which were decreased by eplerenone. However, proliferating cell nuclear antigen was increased 2.47 times in the UUO group compared to the sham group in the contralateral kidney (p < 0.01), and those changes are attenuated by eplerenone. The expression of SGK-1 protein and mRNA was upregulated in the contralateral kidney in the UUO group, which is suppressed by eplerenone treatment. NF-κB pathway effecters were also changed markedly in the contralateral kidney in the UUO group and partly reversed by eplerenone. CONCLUSION: Aldosterone induces inflammatory cell proliferation via the MR/SGK-1 and NF-κB pathways and eventually leads to fibrosis in the contralateral kidney.

[Effect of Shenluotong on secretion of ECM and expression of TGF-beta1 in rats mesangial cells of rats].

OBJECTIVE: To investigate the effect of Shenluotong on the expression of transforming growth factor-beta1 (TGF-beta1) and extracellular matrix (ECM) in Ang II-induced MCs. METHOD: Fibronectin (FN) and collagen type IV (Col IV) of extracellular matrix were detected by enzyme-linked immunosorbent assay; the expression of TGF-beta1 mRNA were measured by semi-quantitative reverse transcription-polymerase chain reaction. RESULT: A positive correlation between TGF-beta1 and ECM were found in the present study. FN, Col IV and TGF-beta1 mRNA were inhibited by Shenluotong significantly. CONCLUSION: Shenluotong can decrease the accumulation of ECM and inhibit the expression of TGF-beta1, suggesting further that shenluotong can be used to prevent and treat various glomerular diseases and delay glomerular sclerosis.