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Diabetic kidney disease （DKD） is a common microvascular complication of diabetics mellitus （DM） and the leading cause of end-stage renal disease （ESRD）. Renal interstitial fibrosis （RIF） is the primary pathological basis for DKD progression to ESRD， which significantly increases the mortality rate of DKD patients and burdens patients and society， and it is thus a clinical problem that needs to be solved urgently. The pathogenesis of RIF is complex and mainly associated with excessive deposition of extracellular matrix （ECM）， epithelial-mesenchymal transition （EMT）， oxidative stress， inflammation， and autophagy. Multiple signaling pathways such as transforming growth factor-β1/Smad （TGF-β1/Smad）， nuclear transcription factor-κB （NF-κB）， p38 mitogen-activated protein kinase （p38 MAPK）， secretory glycoprotein/β-catenin （Wnt/β-catenin）， mammalian target of rapamycin （mTOR）， Janus kinase/signal transducer and activator of transcription （JAK/STAT）， neurogenic site-gap homologous protein （Notch）， and nuclear factor E2-associated factor 2 （Nrf2） mediate the development of RIF， which are currently novel targets for DKD therapy. Due to the complexity of its pathogenesis， the current Western medical treatment mainly focuses on essential treatment to improve metabolism， which has poor efficacy and is difficult to prevent the progression of DKD， so it is significant to find new treatment methods clinically. In recent years， many studies have proved that traditional Chinese medicine can alleviate oxidative stress， inhibit inflammatory response， and regulate cellular autophagy by modulating relevant signaling pathways， so as to treat RIF in DKD， which has the advantages of multi-pathway， multi-targeting， multi-linking， and significant therapeutic efficacy. However， there is still a lack of relevant summary. By reviewing the latest research reports in China and abroad， this article examines the roles of the signaling pathways mentioned above in the occurrence and development of RIF in DKD and the recent research progress in the intervention of RIF in DKD by traditional Chinese medicine via these pathways， aiming to provide new ideas and references for further scientific research and clinical practice.
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Objective:To study the changes in long non-coding RNA C2dat1 expression in kidney tissues of rats at different stages of diabetic kidney disease (DKD) and its relationship with renal interstitial fibrosis.Methods:Forty-eight male SD rats were randomly divided into two groups with 24 rats in each group: control group and DKD group. The rats in the control group were fed with ordinary diet, while those in the DKD group were fed with high-fat diet and drank water freely. After eight weeks of feeding, the rats were fasted for 12 h with free access to water. Then, the DKD group was given a one-time intrabitoneal injection of streptozotocin and the control group was given an equal dose of sodium citrate buffer. After 72 h, the random peripheral blood glucose concentration (≥ 16.7 mmol/L for three consecutive days) and urine sugar (positive) were tested to assess the establishment of the diabetes model. Urine, blood and kidney samples were collected at 3, 6, 9 and 12 weeks. The urinary protein excretion rate within 24 h, urinary creatinine and serum total cholesterol were measured by automatic biochemical apparatus. Pathological changes in kidney tissues were observed by HE staining. The expression of calcium/calmodulin-dependent protein kinase Ⅱ delta (CaMK2D), p65, p50, α-SMA and E-cardherin was detected by immunohistochemistry. Quantitative real-time PCR (qPCR) was used to detect the expression of lncRNA C2dat1 and CaMK2D. The relationship of lncRNA C2dat1 with α-SMA, E-cardherin and CaMK2D was analyzed by correlation analysis. In in vitro experiment, renal tubular epithelial cells HK-2 were induced by high glucose. The expression of lncRNA C2dat1 and CaMK2D in HK-2 cells was detected by qPCR after 24, 48 and 72 h of intervention. Results:The rats in the DKD group showed typical symptoms such as polydipsia, polyphagia, significant weight loss and increased blood glucose as compared with the rats in the control group. Results of the biochemical tests revealed that compared with the control group, the DKD group had increased 24 h excretion rate of urinary protein, decreased urinary creatinine and up-regulated total cholesterol. HE staining showed that the rats in the control group had intact glomeruli, normal basement membrane and no mesangial hyperplasia or inflammatory cell infiltration. However, enlarged glomeruli and evenly thickened basement membrane were observed in the DKD group. Immunohistochemistry indicated that the expression of CaMK2D, p50 and α-SMA was higher in the DKD group than in the control group, while the expression of E-cardherin was lower in the DKD group. qPCR results showed that the expression of lncRNA C2dat1 and CaMK2D at mRNA level was higher in the DKD group than in the control group. In in vitro experiment, the expression of lncRNA C2dat1 and CaMK2D at mRNA level was also higher in HK-2 cells induced by high glucose than in the control group. Correlation analysis indicated that lncRNA C2dat1 was positively correlated with α-SMA and CaMK2D, but negatively correlated with E-cardherin. Conclusions:During the progression of DKD, the high expression of lncRNA C2dat1 might promote diabetic renal interstitial fibrosis by regulating the expression of CaMK2D to activate the NF-κB signaling pathway.
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Objective:To determine a relationship between ultrasound shear wave elastography (SWE) and pathological lessions of renal tissues in children with chronic kidney disease (CKD).Methods:It was a cross-sectional observational study, involving children admitted to the Department of Pediatrics of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology from January to December 2021 with definite pathological diagnosis through kidney biopsy. The SWE was used to determine the Young's modulus (elastic modulus) of the cortex and medulla of the upper, middle, and lower poles of the kidney. The renal histopathology was classified or graded. The statistical method was used to analyze the relationship between Young's modulus of the inferior polar cortex (YM cor) and medulla (YM med) of the right kidney and renal pathology. Results:The study included 110 children with definite pathological diagnosis through renal biopsy, aged (10.1±3.4) years old (2-17 years old), with 55 males (50.0%). The body mass index was (20.6±2.4) kg/m 2, and mean arterial pressure was (95±24) mmHg. There were 94 patients (85.4%) with CKD stage 1, 8 patients (7.3%) with CKD stage 2, and 8 patients (7.3%) with CKD stage 3. There was no significant difference of YM cor and YM med in the upper and middle poles of the right kidneys, and YM med in the lower poles of right kidneys in CKD patients with different stages (all P>0.05). Both YM cor [(15.75±3.36) kPa] and YM med [(13.50±2.43) kPa] of CKD stage 3 patients were significantly higher than those of CKD stage 1 patients [(12.94±2.45) kPa, (11.88±2.23) kPa](both P<0.05). There was no significant difference of YM cor and YM med in the lower poles of right kidneys between stage 1 and stage 2 CKD patients (both P>0.05). YM cor[(17.93±3.23) kPa] and YM med [(15.50±1.48) kPa] in patients with crescentic glomerulonephritis were higher than those in patients with focal segmental glomerulosclerosis [(12.71±2.42) kPa, (11.57±2.63) kPa] and mesangial proliferative glomerulonephritis [(12.73±2.04) kPa, (11.48±2.10) kPa](all P<0.05). There was no significant difference of YM cor and YM med between focal segmental glomerulosclerosis and mesangial proliferative glomerulonephritis (both P>0.05). YM cor [(16.30±2.63) kPa] and YM med [(15.54±1.59) kPa] of Lee's Ⅳ grade of IgA nephropathy were higher than those of Lee's Ⅲ grade [(13.32±2.70) kPa, (12.57±2.50) kPa](both P<0.05), while the International Study of Kidney Disease in Children grade of purpura nephritis had no significant correlation with YM cor and YM med (both P>0.05). YM cor [(15.41±2.37) kPa] and YM med [(13.82±2.59) kPa] of interstitial fibrosis/tubular atrophy (T1/T2) group of IgA nephropathy mixed with purpura nephritis were significantly higher than those of T0 group's [(12.99±2.40) kPa, (11.79±2.05) kPa] (both P<0.05). Moreover, crescent formation (C1) group had a higher YM cor [(14.21±2.77) kPa] and YM med [(12.80±2.47) kPa] than those in C0 group [(12.73±2.15) kPa, (11.59±1.97) kPa] (both P<0.05), while YM cor and YM med were unrelated to the mesangial hypercellularity (M), endocapillary cellularity (E), segmental sclerosis or adhesion (S) indicators (all P>0.05). In lupus nephritis patients, YM cor ( r=0.744, P=0.035) and YM med ( r=0.728, P=0.009) were favorably linked with the chronic index, but not with the activity index (both P>0.05). Conclusions:Renal interstitial fibrosis/tubular atrophy and crescentic development are connected with YM cor and YM med at the lower pole of the kidney as measured by SWE. SWE can be used to assess the chronic renal lesions in children with CKD in the early and middle stages. It may develop into a new noninvasive way to assess renal pathology.
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ObjectiveTo observe the modulatory effect of modified Zhenwutang on the interleukin-6 （IL-6）， matrix metallopeptidase-9（MMP-9）， type Ⅳ collagen（COL-Ⅳ） in rats with chronic renal failure （CRF） and to investigate the potential mechanism of its treatment of CRF. MethodFifty male SD rats were randomly divided into a modeling group of 40 rats and a normal group of 10 rats， and the modeling group was prepared by continuous adenine gavage for 12 weeks. After successful modelling， the modelling group was divided into the model group， the low dose （7.2 g·kg-1·d-1） group， the medium dose （14.4 g·kg-1·d-1） group， the high dose （28.8 g·kg-1·d-1） group and the Benadryl hydrochloride （10 mg·kg-1·d-1） group for gavage according to the random number table method， In the normal group and the model group， equal volume of distilled water was administered by gavage for 4 weeks. After the administration， the levels of blood creatinine （SCr）， blood urea nitrogen （BUN） and 24 h urine protein （24 h-UTP） were measured， the levels of serum IL-6 were measured by enzyme linked immunosorbent assay（ELISA）. Immunohistochemistry （IHC） was used to detect intercellular cell adhesion molecule-1 （ICAM-1）， IL-6， MMP-9， and other molecules in the rat kidney. The expression of ICAM-1 mRNA， IL-6 mRNA， MMP-9 mRNA and COL-Ⅳ mRNA in rat kidney tissues was measured by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. The expression levels of ICAM-1， IL-6， MMP-9 and COL-Ⅳ in rat kidney tissues were measured by Western blot. ResultCompared with the normal group， the levels of SCr， BUN and 24 h-UTP were significantly increased in the model group （P<0.01）； the serum IL-6 level was significantly increased （P<0.01）， the tubular lumen was dilated with atrophy， the tubular epithelial cells were necrotic， swollen and vacuolated， the interstitium was infiltrated by a large number of inflammatory cells and collagen fibers were deposited， the levels of IL-6， ICAM-1 and COL-Ⅳ were strongly positive in the tubular interstitium of the model group （P<0.01）， The levels of ICAM-1 mRNA， IL-6 mRNA and COL-Ⅳ mRNA were significantly increased （P<0.01） and MMP-9 mRNA was significantly decreased （P<0.05） in the model rats. ICAM-1， IL-6 and COL-Ⅳ protein expression was significantly increased （P<0.01） and MMP-9 protein expression was significantly increased （P<0.01） in the renal tissue， and MMP-9 protein expression was significantly decreased （P<0.01）. Compared with the model group， the 24 h-UTP， SCr and BUN levels of rats were significantly reduced after treatment with modified Zhenwutang （P<0.01）， the serum IL-6 level was significantly decreased （P<0.01）， the renal lesions of rats were significantly improved and collagen fiber deposition was reduced； the expression of IL-6， ICAM-1 and COL-Ⅳ in renal tubules and interstitium was weakened， and MMP-9 in ICAM-1 mRNA， IL-6 mRNA and COL-Ⅳ mRNA levels were significantly reduced （P<0.01） and MMP-9 mRNA levels were significantly increased （P<0.05）， ICAM-1， IL-6 and COL-Ⅳ protein expression was significantly reduced （P<0.01） and MMP-9 protein expression was significantly The expression of ICAM-1， IL-6 and COL-Ⅳ proteins was significantly decreased （P<0.01） and MMP-9 protein expression was significantly increased （P<0.01）. ConclusionModified Zhenwutang may regulate the IL-6/MMP-9/COL-Ⅳ signaling pathway， thereby reducing proteinuria， improving renal function， reducing renal pathological damage and delaying the progression of CRF interstitial fibrosis.
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ObjectiveTo explore the underlying mechanism of modified Zhenwutang in delaying renal interstitial fibrosis in chronic renal failure （CRF） by observing the effects of modified Zhenwutang on the expression of angiotensin Ⅱ （Ang Ⅱ）， angiotensin Ⅱ type 1 receptor （AT1R）， nicotinamide adenine dinucleotide phosphate （NADPH） oxidase 4 （NOX4）， transforming growth factor-β1 （TGF-β1）， type I collagen （COL1A1）， and type Ⅲ collagen （COL3A1） in the serum and renal tissues of adenine-induced CRF rats. MethodFifty male SPF-grade SD rats were randomly divided into a normal group （n=10） and an experimental group （n=40） using a random number table. After one week of adaptive feeding， the experimental CRF model was established in rats by administering adenine at 150 mg·kg-1·d-1 orally. Three rats from each group were randomly selected to evaluate the model induction. After successful modeling， rats in the experimental group were randomly divided into a model group， low-， medium， and high-dose modified Zhenwutang groups， and a benazepril hydrochloride group， with six rats in each group. The rats were orally administered the corresponding drugs once daily for four weeks. At the end of the first week， 13th week， and 17th week of the experiment， 24 hour urinary protein quantification （24 h-UTP） was measured. At the end of the 17th week， the rats were euthanized， and blood samples were collected from the abdominal aorta for the measurement of total protein （TP）， albumin （ALB）， creatinine （Cr）， and blood urea nitrogen （BUN） in the serum. Enzyme-linked immunosorbent assay （ELISA） was used to measure the expression levels of serum Ang Ⅱ. Hematoxylin-eosin （HE） staining and Masson's trichrome staining were performed to observe the pathological changes in renal tissues. Immunohistochemistry （IHC） was performed to observe the expression of AT1R， NOX4， TGF-β1， COL1A1， and COL3A1. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to observe the mRNA expression levels of AT1R， NOX4， and TGF-β1. Western blot was conducted to measure the protein expression levels of AT1R， NOX4， and TGF-β1. Result① Compared with the normal group， the model group showed a significant increase in 24 h-UTP （P<0.01）. The levels of Cr and BUN in the model group were significantly higher （P<0.01）， while the levels of TP and ALB were significantly lower （P<0.01）. The serum Ang Ⅱ level in the model group was significantly elevated （P<0.01）. The model group exhibited widening of the renal glomerular mesangial space， necrotic glomeruli， increased interstitial width with extensive inflammatory cell infiltration， brownish precipitates blocking the renal tubular lumens， irregular renal tubules， and significant deposition of collagen fibers in the renal interstitium. Additionally， the collagen fibers around the renal vessels， outside the parietal layer of the renal sacs， glomerular basement membrane， and tubular basement membrane increased significantly. The expression of AT1R and NOX4 in the glomeruli and renal tubules of the model group was significantly enhanced， and TGF-β1 expression also significantly increased in the renal tubules. The expression of COL1A1 and COL3A1 in the renal interstitium significantly increased. The mRNA expression of AT1R and TGF-β1 in the model group significantly increased （P<0.01）， while NOX4 mRNA expression significantly decreased （P<0.01）. The protein expression of AT1R， NOX4， and TGF-β1 was significantly enhanced （P<0.01）. ② Compared with the model group， modified Zhenwutang significantly reduced 24h-UTP （P<0.01）， decreased levels of Cr and BUN （P<0.01）， increased levels of TP and ALB （P<0.01）， reduced serum Ang Ⅱ level （P<0.01）， alleviated renal pathological damage， reduced expression of AT1R， NOX4， TGF-β1， COL1A1， and COL3A1 in the glomeruli， renal tubules， and renal interstitium， reduced mRNA expression of AT1R and TGF-β1 （P<0.01）， increased NOX4 mRNA expression （P<0.01）， and weakened protein expression of AT1R， NOX4， and TGF-β1 （P<0.01）. The modified Zhenwutang groups showed a significant dose-effect trend. ConclusionModified Zhenwutang may delay renal interstitial fibrosis in CRF rats by reducing the expression of Ang Ⅱ， AT1R， NOX4， and TGF-β1 in the serum and renal tissues， thereby alleviating renal pathological damage， reducing proteinuria， protecting renal function， and delaying the progression of CRF. The modified Zhenwutang group exhibited a dose-effect trend.
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Objective:To explore the role of thioredoxin interaction protein (TXNIP)/NOD-like receptor protein 3 (NLRP3) pathway in renal interstitial fibrosis induced by renal ischemia-reperfusion injury (IRI) in mice.Methods:Adult male C57BL/6J mice aged 6 to 8 weeks and TXNIP knockout mice with the same genetic background were selected. The wild type mice were divided into the sham operation (Sham) group and renal IRI group. The TXNIP knockout mice were divided into the sham+TXNIP KO group and IRI+TXNIP KO group, with 12 mice in each group. The model of renal ischemia-reperfusion injury was established by clamping bilateral renal pedicles for 45 min and then restoring perfusion. The sham operation model was only dissociated bilateral renal arteries without other treatment. Blood creatinine, urea nitrogen, kidney injury molecule-1 (Kim-1) and neutrophil gelatinase-associated lipocalin (NGAL), blood transforming growth factor-β (TGF-β) and interleukin 6 (IL-6) were measured on the 1st, 7th and 28th days after reperfusion. The renal cortex was taken on the 1st and 28th days for Masson staining, in which the renal tubule-interstitial injury score was obtained. TGF-β and IL-6 mRNA expression were detected by qPCR, TXNIP, NLRP3, Pro-IL-1β, IL-1β and α-SMA protein expression were detected by Western blot, and MDA and SOD levels were detected by ELISA. Homogeneity test of variance was performed before the statistics of normal distribution measurement data, one-way ANOVA was used for the comparison between multiple groups, and LSD- t test was used for the comparison between the two groups. Results:On the 1st, 7th and 28th days after IRI, compared with the sham group, the Scr, BUN, Kim-1, NGAL, TGF-β and IL-6 were increased continuously in the IRI group ( P<0.05). On the 28th day after IRI, large areas of collagen fibers and inflammatory cell infiltration were observed in the renal interstitium of the IRI group. In the IRI group, the scores of renal tubular injury and renal interstitial fibrosis on the 28th day were significantly higher than those on the 1st day (all P<0.05). On the 1st, 7th and 28th days after IRI, compared with the IRI group, the levels of Scr, BUN, Kim-1, NGAL, TGF-β and IL-6 were significantly decreased in the IRI+TXNIP KO group (all P<0.05). On the 1st and 28th days after IRI, compared to the IRI group, the areas of collagen fibers and inflammatory cell infiltration in the renal interstitium of the IRI+TXNIP KO group were decreased. The renal tubule injury score [Day 1, (192.2 ± 62.4) vs. (103.2 ± 49.1); Day 28, (154.3 ± 93.6) vs. (64.3 ± 24.8), both P<0.05] and interstitial fibrosis score [Day 1, (7.3 ± 3.2) vs. (4.8 ± 1.7); Day 28, (12.8 ± 3.9) vs. (2.3 ± 0.8), both P<0.05] were all decreased. The expression of TGF-β, IL-6 mRNA, TXNIP, NLRP3, Pro-IL-1 β, IL-1 β and α-SMA protein in renal cortex were significantly decreased (both P<0.05). In renal cortex, MDA level was decreased and SOD level was increased (all P<0.05). Conclusions:TXNIP/NLRP3 pathway is involved in the development of renal interstitial inflammation and fibrosis after renal ischemia and reperfusion. Knockout or inhibition of TXNIP can inhibit the progression of acute renal injury to chronic renal disease.
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OBJECTVE To study the improvement effects of obacunone on renal interstitial fibrosis （RIF） in unilateral ureteral obstruction （UUO） model mice， and to investigate its mechanism based on ferroptosis mediated by nuclear factor erythroid 2- related factor 2（Nrf2）/glutathione peroxidase 4 （GPx4） signaling pathway. METHODS Thirty mice were randomly divided into sham operation group， model group， irbesartan group （positive control， 20 mg/kg）， obacunone low-dose and high-dose groups （10， 40 mg/kg）， with 6 mice in each group. Except for sham operation group， UUO model was established by ligation of unilateral ureter in other groups. After operation， administration groups were given intraperitoneal injection of relevant medicine， and sham operation group and model group were given intraperitoneal injection of constant volume of normal saline， once a day， for 7 consecutive days. The levels of creatinine （Cr） and blood urea nitrogen （BUN）， the content of malondialdehyde （MDA） and the activities of total superoxide dismutase （T-SOD） in serum and the concentration of Fe2+ in renal tissue were all detected. HE staining and Masson staining were performed to observe the morphology and the fibrosis of renal tissues. Immunohisto- chemical staining was used to determine expressions of the fibronectin （Fn）， α-smooth muscle actin （α-SMA）， GPx4 964083717@qq.com and Nrf2 in renal tissue. Western blot and real-time quantitative polymerase chain reaction （RT-qPCR） were used E-mail：834300205@qq.com to detect the protein and mRNA levels of Fn， α-SMA， Nrf2， GPx4 and SLC7A11 in the renal tissues. RESULTS Compared with sham operation group， serum levels of Cr and BUN， the concentration of Fe2+ in renal tissue， the protein and mRNA levels of Fn and α-SMA in model group were increased significantly （P＜0.05）， while the activity of T-SOD in serum， protein and mRNA expressions of Nrf2， GPx4， SLC7A11 in kidney tissue were significantly decreased （P＜0.05）； in the kidney tissue， the renal tubules were dilated， the collagen deposition was obvious， the fibrous bands were thicker and darker， and the renal interstitial inflammatory cells infiltrated significantly. After intervened with obacunone， the levels of above indexes （except for mRNA expression of SLC7A11 in obacunone low-dose group） in serum and renal tissue were reversed significantly （P＜0.05）， and pathological damage and collagen deposition of kidney tissue were alleviated. CONCLUSIONS Obacunone can improve renal interstitial fibrosis of UUO model mice， the mechanism of which may be associated with activating the Nrf2/GPx4 pathway and then inhibiting ferroptosis to relieve RIF in UUO model mice.
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ObjectiveTo observe the intervention effect of Dahuang Xiezhuo prescription （DHXZ） on inflammation and suppressor of cytokine signaling 3 （SOCS3）/Toll-like receptor 4 （TLR4） pathway in rats with chronic renal failure （CRF）， and to explore its molecular mechanism in alleviating renal inflammatory response. MethodThe 90 male SD rats， 15 were randomly selected as sham group， and the remaining 75 were used as modeling group to replicate CRF rat model by 5/6 nephrectomy. After successful modeling， the rats were randomly divided into model group， DHXZ low-， medium-， high-dose groups （6.825， 13.65， 27.3 g·kg-1） and Niaoduqing Granules group （2.6 g·kg-1）. The drug intervention groups received corresponding drugs by gavage for 8 consecutive weeks. After administration， hematoxylin-eosin （HE） staining and Masson staining were used to observe the morphological changes of rat renal tissue， and blood creatinine （SCr）， blood urea nitrogen （BUN） and blood uric acid （UA） were tested. Enzyme-linked immunosorbent assay （ELISA） was performed to detect the serum contents of interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α） and C-reactive protein （CRP）. The mRNA expressions of SOCS3 and TLR4 in renal tissue were detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， and the protein expressions of SOCS3， TLR4， nuclear transcription factor （NF-κB） and myeloid differentiation factor （MyD88） were detected by Western blot. Immunohistochemistry was used to determine the protein expressions of NF-κB， MyD88， NOD-like receptor protein 3 （NLRP3） and melanoma deficiency factor 2 （AIM2）. ResultCompared with the sham group， the model group had a significant inflammatory response in renal tissue， and an increase in blood SCr， BUN， UTP， IL-6， TNF-α and CRP （P<0.05）. The protein and mRNA expressions of SOCS3 in renal tissue of rats in the model group were lower while the protein expressions of TLR4， NF-κB， MyD88， NLRP3 and AIM2 and the mRNA expression of TLR4 were higher than those in the sham group （P<0.05）. Compared with the model group， DHXZ and Niaoduqing granules groups presented markedly reduced inflammatory response in renal tissue and decreased blood SCr， BUN， UTP， IL-6， TNF-α and CRP （P<0.05）. Additionally， DHXZ and Niaoduqing granules up-regulated the protein and mRNA expressions of SOCS3 in renal tissue while down-regulated the protein expressions of TLR4， NF-κB， MyD88， NLRP3 and AIM2 and the mRNA expression of TLR4 （P<0.05）. ConclusionDHXZ can reduce the release and expression of inflammatory factors， inhibit the inflammatory response and improve renal function， and the mechanism may be related to the regulation of SOCS3/TLR4 signaling pathway.
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Renal interstitial fibrosis (RIF) is the crucial pathway in chronic kidney disease (CKD) leading to the end-stage renal failure. However, the underlying mechanism of Shen Qi Wan (SQW) on RIF is not fully understood. In the current study, we investigated the role of Aquaporin 1 (AQP1) in SQW on tubular epithelial-to-mesenchymal transition (EMT). A RIF mouse model induced by adenine and a TGF-β1-stimulated HK-2 cell model were etablished to explore the involvement of AQP 1 in the protective effect of SQW on EMT in vitro and in vivo. Subsequently, the molecular mechanism of SQW on EMT was explored in HK-2 cells with AQP1 knockdown. The results indicated that SQW alleviated kidney injury and renal collagen deposition in the kidneys of mice induced by adenine, increased the protein expression of E-cadherin and AQP1 expression, and decreased the expression of vimentin and α-smooth muscle actin (α-SMA). Similarly, treatmement with SQW-containing serum significantly halted EMT process in TGF-β1 stimulated HK-2 cells. The expression of snail and slug was significantly upregulated in HK-2 cells after knockdown of AQP1. AQP1 knockdown also increased the mRNA expression of vimentin and α-SMA, and decreased the expression of E-cadherin. The protein expression of vimentin increased, while the expression of E-cadherin and CK-18 significantly decreased after AQP1 knockdown in HK-2 cells. These results revealed that AQP1 knockdown promoted EMT. Furthermore, AQP1 knockdown abolished the protective effect of SQW-containing serum on EMT in HK-2 cells. In sum, SQW attentuates EMT process in RIF through upregulation of the expression of AQP1.
Subject(s)
Humans , Animals , Mice , Male , Rats , Drugs, Chinese Herbal/pharmacology , Cell Line , Kidney/physiology , Fibrosis/drug therapy , Renal Insufficiency, Chronic/drug therapy , Adenine , Epithelial-Mesenchymal Transition , Aquaporin 1/metabolismABSTRACT
This study aims to explore the effect of icariin(ICA) on mitochondrial dynamics in a rat model of chronic renal failure(CRF) and to investigate the molecular mechanism of ICA against renal interstitial fibrosis(RIF). CRF was induced in male Sprague-Dawley(SD) rats with 5/6(ablation and infarction, A/I) surgery(right kidney ablation and 2/3 infarction of the left kidney). Four weeks after surgery, the model rats were randomized into the following groups: 5/6(A/I) group, 5/6(A/I)+low-dose ICA group, and 5/6(A/I)+high-dose ICA group. Another 12 rats that received sham operation were randomly classified into 2 groups: sham group and sham+ICAH group. Eight weeks after treatment, the expression of collagen-Ⅰ(Col-Ⅰ), collagen-Ⅲ(Col-Ⅲ), mitochondrial dynamics-related proteins(p-Drp1 S616, p-Drp1 S637, Mfn1, Mfn2), and mitochondrial function-related proteins(TFAM, ATP6) in the remnant kidney tissues was detected by Western blot. The expression of α-smooth muscle actin(α-SMA) was examined by immunohistochemical(IHC) staining. The NRK-52 E cells, a rat proximal renal tubular epithelial cell line, were cultured in vitro and treated with ICA of different concentration. Cell viability was detected by CCK-8 assay. In NRK-52 E cells stimulated with 20 ng·mL~(-1) TGF-β1 for 24 h, the effect of ICA on fibronectin(Fn), connective tissue growth factor(CTGF), p-Drp1 S616, p-Drp1 S637, Mfn1, Mfn2, TFAM, and ATP6 was detected by Western blot, and the ATP content and the mitochondrial morphology were determined. The 20 ng·mL~(-1) TGF-β1-stimulated NRK-52 E cells were treated with or without 5 μmol·L~(-1) ICA+10 μmol·L~(-1) mitochondrial fusion promoter M1(MFP-M1) for 24 h and the expression of fibrosis markers Fn and CTGF was detected by Western blot. Western blot result showed that the levels of Col-Ⅰ, Col-Ⅲ, and p-Drp1 S616 were increased and the levels of p-Drp1 S637, Mfn1, Mfn2, TFAM, and ATP6 were decreased in 5/6(A/I) group compared with those in the sham group. The levels of Col-Ⅰ, Col-Ⅲ, and p-Drp1 S616 were significantly lower and the levels of p-Drp1 S637, Mfn1, Mfn2, TFAM, and ATP6 were significantly higher in ICA groups than that in 5/6(A/I) group. IHC staining demonstrated that for the expression of α-SMA in the renal interstitium was higher in the 5/6(A/I) group than in the sham group and that the expression in the ICA groups was significantly lower than that in the 5/6(A/I) group. Furthermore, the improvement in the fibrosis, mitochondrial dynamics, and mitochondrial function were particularly prominent in rats receiving the high dose of ICA. The in vitro experiment revealed that ICA dose-dependently inhibited the increase of Fn, CTGF, and p-Drp1 S616, increased p-Drp1 S637, Mfn1, Mfn2, TFAM, and ATP6, elevated ATP content, and improved mitochondrial morphology of NRK-52 E cells stimulated by TGF-β1. ICA combined with MFP-M1 further down-regulated the expression of Fn and CTGF in NRK-52 E cells stimulated by TGF-β1 compared with ICA alone. In conclusion, ICA attenuated RIF of CRF by improving mitochondrial dynamics.
Subject(s)
Animals , Female , Humans , Male , Rats , Adenosine Triphosphate/pharmacology , Fibrosis , Flavonoids , Infarction/pathology , Kidney , Kidney Failure, Chronic , Mitochondrial Dynamics , Rats, Sprague-Dawley , Renal Insufficiency, Chronic , Transforming Growth Factor beta1/metabolismABSTRACT
Objective:The unilateral (left) ureteral obstruction (UUO) model was established in mice to explore the changes of renal injury with time and the related mechanisms.Methods:Fifty mice were randomly divided into two groups: sham group and UUO group (UUO model was made by unilateral ureteral ligation). The biochemical indexes, left kidney weight/final weight (LR/BW) and right kidney weight/final weight (RR/BW) of the two groups at different time points were observed, and the left kidney weight/right kidney weight ratio (LR/RR) was calculated. Hematoxylin-eosin (HE), Masson and periodic acid-Schiff (PAS) staining were used to detect the pathological changes of the kidney in mice. Immunofluorescence staining was used to observe the loss of peritubular capillaries (PTC), proliferation of renal parenchymal cells (Ki67 + cells), macrophages (CD68 + markers), infiltration of fibroblasts and expression of Wnt/β-catenin in the kidney of mice. Results:The weight of mice in UUO group decreased rapidly [(18.2±1.1)g vs (22.4±1.2)g] on the third day of modeling, then slowly increased until the 28th day, and significantly decreased [(17.5±0.8)g] on the 60th day; LR/RR and LR/BW increased significantly in the third day, and then decreased gradually; Renal function of mice in UUO group deteriorated significantly on the 60th day [serum creatinine (0.89±0.09)mg/dl, urea nitrogen (41.26±5.65)mg/dl]. In UUO group, renal tubulointerstitial fibrosis and glomerulosclerosis were observed under light microscope in the obstructed kidney; with the passage of time, PTC loss gradually increased; macrophages increased significantly in the left renal parenchyma at first, but began to decrease 28 days later; the number of fibroblasts increased significantly in the first 14 days of the obstructed side (left side) kidney, and then decreased to the normal level; There was no significant difference in the cell number of the non obstructive kidney between UUO group and sham group; The immunofluorescence intensity expression of Wnt/β- catenin of obstructive side (left side) in UUO group was significantly up-regulated in the first 14 days after renal injury, and decreased after 28 days.Conclusions:The development of UUO renal fibrosis involves many changes, including PTC loss, macrophage infiltration, fibroblast activation and expression, but these changes weaken with time.
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Objective:To investigate the changes of serum micro ribonucleic acid-155 (miR-155) and suppressor of cytokine signaling-1 (SOCS-1) levels in patients with IgA nephropathy and their relationship with renal interstitial fibrosis.Methods:A total of 365 patients with primary IgA nephropathy admitted to Jining First People′s Hospital from January 2009 to June 2018 were selected as the research objects. According to the degree of renal interstitial fibrosis, the patients were divided into T0 group (139 cases), T1 group (124 cases) and T2 group (102 cases). In addition, 361 healthy subjects who had physical examination in our hospital in the same period were selected as the healthy control group. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression level of miR-155 in serum of all the subjects; the levels of serum SOCS-1, transforming growth factor-β1 (TGF-β1) and monocyte chemoattractant protein-1 (MCP-1) were detected by enzyme-linked immunosorbent assay (ELISA). Logistic regression model was used to analyze the influencing factors of renal interstitial fibrosis in patients with IgA nephropathy; Pearson method was used to analyze the correlation between serum miR-155, SOCS-1 levels and influencing factors of renal interstitial fibrosis, TGF-β1 and MCP-1; receiver operating characteristic (ROC) curve was used to analyze the predictive value of serum miR-155 and SOCS-1 levels in patients with IgA nephropathy.Results:The levels of systolic blood pressure (SBP), diastolic blood pressure (DBP), 24 h urine protein, serum creatinine, serum uric acid, miR-155, TGF-β1, MCP-1, urinary retinol binding protein (RBP) and acetyl β D-glucosaminidase (NAG) in healthy control group, T0 group, T1 group and T2 group were significantly increased in turn, while the levels of hemoglobin, estimated glomerular filtration rate (eGFR), urinary osmotic pressure and serum SOCS-1 were significantly decreased in turn (all P<0.05). High SBP, high DBP, low hemoglobin, high serum creatinine, high uric acid, high 24-hour urine protein and low eGFR level were independent risk factors of renal interstitial fibrosis in patients with IgA nephropathy (all P<0.05). The serum miR-155 level was positively correlated with TGF-β1, MCP-1, SBP, DBP, serum creatinine, serum uric acid levels and 24 h urine protein, but negatively correlated with SOCS-1, hemoglobin and eGFR levels (all P<0.05). The serum SOCS-1 level was negatively correlated with TGF-β1, MCP-1, SBP, DBP, serum creatinine, uric acid levels and 24 h urine protein, but positively correlated with hemoglobin and eGFR levels (all P<0.05). The area under the curve of predicting the occurrence of renal interstitial fibrosis in patients with IgA nephropathy by serum miR-155 and SOCS-1 combined detection was 0.882, which was significantly larger than that by serum miR-155 and SOCS-1 alone ( P<0.05). Conclusions:The expression of miR-155 is up-regulated and SOCS-1 is down-regulated in IgA nephropathy patients, they may be used as predictors to evaluate the occurrence of renal interstitial fibrosis.
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ObjectiveTo observe the effect of Dahuang Xiezhuo prescription on the changes in renal pathology and reactive oxygen species （ROS）/thioredoxin-interacting protein （TXNIP）/NOD-like receptor protein 3 （NLRP3） pathway expression in the kidney tissues of rats with 5/6 nephrectomy， and to explore the mechanism of Dahuang Xiezhuo prescription in protecting renal function and delaying renal interstitial fibrosis and the possibility. MethodNinety healthy male SD rats were randomly divided into a sham operation group， a model group， low， medium， and high-dose （6.825， 13.65， 27.30 g·kg-1） Dahuang Xiezhuo prescription groups， and a Niaoduqing granule group （2.60 g·kg-1）. Except the sham operation group， 5/6 nephrectomy was used to replicate the rat model of chronic renal failure （CRF）. After modeling， each administration group was given the corresponding dose of drug suspension by intragastric administration， once a day for consecutive 8 weeks. After administration， serum creatinine （SCr） and urea nitrogen （BUN） levels and 24 h urinary protein quantification （UTP） levels were detected. Western blot assay was used to detect the protein expressions of thioredoxin （TRX）， TXNIP， and NLRP3. The protein expressions of TRX， TXNIP， NLRP3， apoptosis-associated speck-like protein containing a CARD （ASC）， transformation growth factor-β （TGF-β）， Collagen Ⅳ， α-smooth muscle actin （α-SMA）， and fibronectin （FN） were detected by immunohistochemistry. ResultAs compared with the sham operation group， serum levels of SCr， BUN， and UTP in the model group were increased （P<0.05）， TRX， TXNIP， NLRP3， ASC， TGF-β， Collagen Ⅳ， α-SMA， and FN proteins were increased （P<0.01）， and renal interstitial fibrosis significantly occurred. As compared with the model group， the levels of SCr， 24 h BUN， and UTP in the low， medium， and high-dose Dahuang Xiezhuo prescription groups and the Niaoduqing granule group were decreased to varying degrees （P<0.05）， TRX， TXNIP， NLRP3， ASC， TGF-β， Collagen Ⅳ， α-SMA， and FN were decreased （P<0.01）， and renal interstitial fibrosis was improved to varying degrees. ConclusionDahuang Xiezhuo prescription can protect renal function and delay renal interstitial fibrosis in rats with CRF.
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ObjectiveTo explore the mechanism of Yishen Huoxue prescription in renal interstitial fibrosis （RIF） from the perspective of endothelial cell and cell energy metabolism. MethodThe model was successfully established by unilateral ureteral obstruction （UUO）. Seventy-five SPF C57BL/6 mice were randomly divided into a model group， a resveratrol group （50 mg·kg-1·d-1）， three Yishen Huoxue prescription low， medium， and high-dose groups （7.1， 14.2， 28.4 g·kg-1·d-1）， with 15 mice in each group. In addition， another 15 mice were used to prepare sham operation model. Mice in the sham operation group and the model group were gavaged with equal volume of normal saline. All mice were sacrificed on 7， 14， and 21 d after modeling. The protein expression of platelet endothelial cell adhesion molecule 31 （CD31） was detected by immunohistochemical S-P method. The expression of α-smooth muscle actin （α-SMA）， collagen Ⅳ （Col-Ⅳ）， angiopoietin 1（Ang-1） and tyrosine kinase receptors 2 （Tie-2）， vascular endothelial growth factor （VEGF）， vascular endothelial cadherin （VE-cadherin）， and occludin in renal tissues was detected by Western blotting. The mRNA expressions of Ang-1/Tie-2， VEGF， VE-cadherin， and occludin in renal tissues were detected by Real-time fluorescence quantitative polymerase chain reaction（Real-time PCR）， and the levels of reactive oxygen species （ROS） in mice were detected by enzyme linked immunosorbent assay （ELISA）. ResultAs compared with the sham operation group， the expression of CD31 in renal tissues of the model group was significantly decreased and worsened with the extension of modeling time （P<0.05）， α-SAM and Col-Ⅳ protein expression levels were significantly increased （P<0.01）， but the expression of CD31 was stable in 14-21 d. ROS levels were significantly increased （P<0.01）， and the protein and mRNA expressions of Ang-1/Tie-2， VEGF， VE-cadherin， and occludin were significantly down-regulated （P<0.01）. As compared with the model group， the expression of CD31 was increased （P<0.05）， and α-SAM and Col-Ⅳ in the resveratrol group and the medium and high-dose Yishen Huoxue prescription groups were significantly decreased （P<0.01）. The ROS content was significantly decreased （P<0.01）， and the protein and mRNA expressions of Ang-1/Tie-2， VEGF， VE-cadherin， and occludin were up-regulated （P<0.01）， As compared with the resveratrol group， the protein expressions of Ang-1/Tie-2， VEGF， VE-cadherin， and occludin in the medium and low-dose Yishen Huoxue prescription groups were significantly different （P<0.01）. There was no significant difference in the mRNA expressions of CD31 and Ang-1/Tie-2 in the high-dose Yishen Huoxue prescription group， and no significant difference in the ROS level in the medium-dose Yishen Huoxue prescription group. ConclusionThe anti-RIF effect of Yishen Huoxue prescription may be related to promoting vascular endothelial repair， regulating mitochondrial ROS to reduce oxidative stress， protecting the integrity of renal endothelial structure， delaying cell apoptosis， and maintaining cell energy metabolism.
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ObjectiveTo observe the mechanism of modified Shengjiangsan in necroptosis and renal fibrosis of rats with diabetic nephropathy based on receptor-interacting protein （RIP）1/RIP3/mixed lineage kinase domain-like protein （MLKL） signaling pathway. MethodSeventy-five SD rats were randomly divided into a model group， a normal group， three high， medium， and low-dose modified Shengjiangsan groups （4.365， 8.73， 17.46 g·kg-1）， and an irbesartan group （0.013 5 g·kg-1）. After 4 weeks of intragastric administration， the levels of 24 h urine protein （UTP）， tumor necrosis factor-α （TNF-α）， and interleukin-1β （IL-1β） of rats in each group were determined， as well as the changes in degree of renal pathology. Real-time quantitative polymerase chain reaction （Real-time PCR） and immunohistochemistry were used to detect the mRNA and protein expression levels of IL-1β， TNF-α， monocyte chemoattractant protein-1 （MCP-1）， transforming growth factor-β1 （TGF-β1）， and nuclear factor kappa B （NF-κB） in kidney tissues of rats. Western blot assay was used to detect the expression levels of key proteins in the RIP1/RIP3/MLKL signaling pathway. ResultAs compared with the normal group， the renal interstitial fibrosis in the model group was obvious， and the 24 h UTP， IL-1β， TNF-α levels were significantly increased （P<0.05）. In the model group， the mRNA and protein expression levels of IL-1β， TNF-α， MCP -1， TGF-β1， and NF-κB in the kidney tissues were significantly increased （P<0.05）， and protein expression levels of RIP1， RIP3， p-MLKL， and MLKL were significantly increased （P<0.05）. Compared with the model group， all modified Shengjiangsan groups and the irbesartan group improved the levels of renal interstitial fibrosis in rats to varying degrees. As compared with the model group， the 24 h UTP levels in all modified Shengjiangsan groups and the irbesartan group were decreased to varying degrees （P<0.05）， the content of IL-1β and TNF-α in the serum were decreased （P<0.05）， the mRNA and protein expression levels of IL-1β， TNF-α， MCP-1， TGF-β1， and NF-κB in renal tissues was down-regulated （P<0.05）， and the protein expression levels of RIP1， RIP3， p-MLKL， and MLKL were down-regulated （P<0.05）. ConclusionModified Shengjiangsan ameliorates renal injury of rats with diabetic nephropathy， and the mechanism may be related to the down-regulation of the RIP1/RIP3/MLKL signaling pathway， the prevention of renal tissue necroptosis， and the inhibition of renal fibrosis.
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Chronic kidney disease （CKD） has become a public health problem worldwide with renal interstitial fibrosis （RIF） serving as the important pathological feature and pathological outcome of various CKD. Therefore， anti-fibrosis therapy has important practical significance for delaying the progression of CKD and improving the prognosis of CKD patients. The Wnt/β-catenin signaling pathway is a conserved signaling pathway through evolution， which plays a vital role in organ formation， tissue homeostasis， and disease progression during embryonic development. A growing body of research has confirmed that the Wnt/β-catenin signaling pathway is one of the key signaling pathways in a variety of kidney diseases and its activation is closely related to RIF. RIF is aggravated by the specific regulation of the expression of downstream target genes， such as fibroblasts， zinc finger transcription factor 1 （Snail1）， M2 macrophages， matrix metalloproteinase-7 （MMP-7）， plasminogen activator inhibitor-1 （PAI-1）， and renin-angiotensin system（RAS）， and relieved by targeting the signaling pathways， such as Klotho， Dickkopf-related protein 1 （DKK1）， secreted frizzled-related protein 1 （Sfrp1）， and indocyanine green-001. In addition，the pathological view of RIF in traditional Chinese medicine （TCM） coincides with that in western medicine. Based on the etiology and pathogenesis of TCM in the combination of deficiency and excess， TCM regulates fibrosis-promoting mediators by tonifying deficiency， eliminating turbidity， removing the toxin， resolving stasis， and treating both symptoms and root causes in a multi-target， multi-layer， and multi-pathway manner to inhibit the Wnt/β-catenin signaling pathway and play an important role in renal protection. Therefore， this study reviewed the regulatory mechanism of the Wnt/β-catenin signaling pathway in RIF and the protective effect of targeting this signaling pathway on renal function and discussed the potential role of TCM in delaying the progression of RIF， which is expected to provide new targets and strategies for the prevention and treatment of RIF.
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Renal interstitial fibrosis（RIF）is a common pathway for the progression of chronic kidney disease to renal failure，and its pathogenesis is mainly related to renal inflammatory damage，oxidative stress，apoptosis，and excessive extracellular matrix（ECM） deposition. Transforming growth factor-β1（TGF-β1） signaling pathway，mammalian target of rapamycin（mTOR） signaling pathway and other signaling pathways mediate the occurrence and development of RIF. Because of the complicated mechanism of RIF，there have been no specific prevention and treatment measures in clinical practice. Autophagy is a non-damaging response produced by eukaryotic cells. It maintains the balance of tissue homeostasis through degradation and reabsorption. At present， Chinese medicine has achieved desirable clinical effects with its unique advantages of multiple components，multiple effects，and multiple targets in the treatment of chronic kidney disease to delay the process of RIF. Scholars have found that autophagy is consistent with the Yin-Yang theory and the theory of abdominal mass in traditional Chinese medicine （TCM） to a certain extent，and it is involved in many aspects of RIF. The progression of RIF is closely related to autophagy. The targeted therapy of RIF by intervention in autophagy has become the frontier of research. However，little is known about the role of autophagy in RIF and the regulation of autophagy by Chinese medicine in the treatment of RIF. Therefore，it is necessary to further elucidate the relationship between autophagy and RIF in order to clarify the mechanism of autophagy in RIF and the mechanism of Chinese medicine regulating autophagy in targeted therapy of RIF. This article focused on the correlation between autophagy and RIF based on TCM theory，and systematically summarized the role of autophagy in RIF and the intervention of Chinese medicine by combining the effects of autophagy on inflammation damage，oxidative stress，apoptosis，and excessive ECM deposition in RIF， and the regulation mechanism of autophagy in TGF-β1 and mTOR signaling pathways in RIF. This study was expected to provide a certain reference for the clinical treatment of RIF and the development of new drugs.
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Renal interstitial fibrosis（RIF）is a common pathway for the progression of chronic kidney disease to renal failure，and its pathogenesis is mainly related to renal inflammatory damage，oxidative stress，apoptosis，and excessive extracellular matrix（ECM） deposition. Transforming growth factor-β1（TGF-β1） signaling pathway，mammalian target of rapamycin（mTOR） signaling pathway and other signaling pathways mediate the occurrence and development of RIF. Because of the complicated mechanism of RIF，there have been no specific prevention and treatment measures in clinical practice. Autophagy is a non-damaging response produced by eukaryotic cells. It maintains the balance of tissue homeostasis through degradation and reabsorption. At present， Chinese medicine has achieved desirable clinical effects with its unique advantages of multiple components，multiple effects，and multiple targets in the treatment of chronic kidney disease to delay the process of RIF. Scholars have found that autophagy is consistent with the Yin-Yang theory and the theory of abdominal mass in traditional Chinese medicine （TCM） to a certain extent，and it is involved in many aspects of RIF. The progression of RIF is closely related to autophagy. The targeted therapy of RIF by intervention in autophagy has become the frontier of research. However，little is known about the role of autophagy in RIF and the regulation of autophagy by Chinese medicine in the treatment of RIF. Therefore，it is necessary to further elucidate the relationship between autophagy and RIF in order to clarify the mechanism of autophagy in RIF and the mechanism of Chinese medicine regulating autophagy in targeted therapy of RIF. This article focused on the correlation between autophagy and RIF based on TCM theory，and systematically summarized the role of autophagy in RIF and the intervention of Chinese medicine by combining the effects of autophagy on inflammation damage，oxidative stress，apoptosis，and excessive ECM deposition in RIF， and the regulation mechanism of autophagy in TGF-β1 and mTOR signaling pathways in RIF. This study was expected to provide a certain reference for the clinical treatment of RIF and the development of new drugs.
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Objective:To explore the mechanism of cisplatin-induced renal interstitial fibrosis and provide a new idea for the prevention and treatment of renal interstitial fibrosis.Methods:Eight-week-old male C57BL/6 mice (specific pathogen-free) were used to carry out the experiment. The mice were divided into cisplatin group (10 mg/kg, n=6) and saline group ( n=6) with intraperitoneal injection on day 0, 7 and 21, and sacrificed on day 28. The kidney tissues were collected for RNA Illumina high-throughput sequencing, real-time PCR, Western blotting, Masson staining and bioinformatics analysis. Results:Through real-time PCR, Western blotting and Masson staining, a mouse model with cisplatin-induced renal interstitial fibrosis was successfully established. Through RNA Illumina high-throughput sequencing, 387 long noncoding RNA (lncRNA) and 2 427 mRNA were differently expressed between cisplatin group and saline group. The expression of the top two lncRNA was confirmed by real-time PCR with the same tendency as RNA sequencing. Complement C3 was found to be at the top among the different expressed mRNA by RNA sequencing. Several terms related to immunity were found to be within the top 20 terms through Gene Ontology (GO) enrichment analysis. Systemic lupus erythematous pathway (ko05322, Q=3.4E-17), including the complement cascade pathway, was found to be the top pathway through Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The mRNA expression levels of C1q, C2, C3 and C4 were up-regulated remarkably in the cisplatin group by RNA sequencing than those in saline group (all P<0.05) and confirmed by real-time PCR. Conclusions:Renal interstitial fibrosis can be induced by intraperitoneal injection of cisplatin periodically in mice, with complement cascade pathway activation in the diseased kidney.
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OBJECTIVE Chronic kidney disease (CKD) has become a global public health problem with 10％-15％incidence rate, and inhibiting the renal interstitial fibrosis is considered to be a potential strategy to delay the progression of CKD. Z-Guggulsterone (Z-GS), an active compound from derived from Commiphora mukul, has been proved to be effective in various diseases. The present study aimes to determine the protective effect and the molecular mechanism of Z-GS on renal fibrosis. METHODS Unilateral ureteral obstruction (UUO) mice and hypoxia-induced HK-2 cells were used to simulate renal fibrosis in vitro and in vivo, respectively. The mice and cells were treated with different doses of Z-GS to observe the pharmacological action. Renal function, including Scr, BUN, and UA, were detected by commercial kits. H&E and Masson staining were performed to observe histopathological changes of kidney. Cell viability and LDH release of HK-2 cells were detected by commercial kits. Cell cycle distribution and apoptosis rate were analyzed by flow cytometry. Fibrosis markers were detected by immunohistochemistry and immunofluorescence analysis. Cell cycle related proteins and Klotho/p53 signaling were analyzed by Western blotting. RESULTS The results showed that Z-GS decreased the rise of Scr, BUN, and UA and lightened renal histopathological injury, which were induced by UUO. Besides, Z-GS administration alleviated renal fibrosis in mice by inhibiting the expressions of α-SMA, TGF-β and colla?genⅣ, and delayed G2/M cell cycle arrest by promoting the expressions of CDK1 and cyclinD1/B1 rate. Experiments in vitro indicated that Z-GS treatment significantly increased the cell viability while decreased the LDH release in hypoxia-induced HK-2 cells. In addition, hypoxia induced fibrosis and G2/M cycle arrest in HK-2 cells were retarded by Z-GS. The study of its possible mechanism exhibited that Z-GS treatment increased the level of Klotho and inhibited P53 level. Nev?ertheless, the effect of Z-GS on Klotho/P53 signaling was reversed by siRNA-Klotho. Moreover, siRNA-Klotho treatment eliminated the effects of Z-GS on G2/M cell cycle arrest and fibrosis. CONCLUSION This study clarified that Z-GS allevi?ated renal fibrosis and G2/M cycle arrest through Klotho/P53 signaling pathway. People who have suffered CKD may potentially benefit from treatment with Z-GS.