Diabetic kidney disease is an important microvascular complication of diabetes and the leading cause of end-stage renal disease. Its pathological characteristics mainly include epithelial mesenchymal transition(EMT) in glomerulus, podocyte apoptosis and autophagy, and damage of glomerular filtration barrier. Transforming growth factor-β(TGF-β)/Smad signaling pathway is specifically regulated by a variety of mechanisms, and is a classic pathway involved in physiological activities such as apoptosis, proliferation and differentiation. At present, many studies have found that TGF-β/Smad signaling pathway plays a key role in the pathogenesis of diabetic kidney disease. Traditional Chinese medicine has significant advantages in the treatment of diabetic kidney disease for its multi-component, multi-target and multi-pathway characteristics, and some traditional Chinese medicine extracts, traditional Chinese medicines and traditional Chinese medicine compound prescription improve the renal injury of diabetic kidney disease by regulating TGF-β/Smad signaling pathway. This study clarified the mechanism of TGF-β/Smad signaling pathway in diabetic kidney disease by expounding the relationship between the key targets of the pathway and diabetic kidney disease, and summarized the research progress of traditional Chinese medicine in the treatment of diabetic kidney disease by interfering with TGF-β/Smad signaling pathway in recent years, to provide reference for drug research and clinical treatment of diabetic kidney disease in the future.
Humans ; Diabetic Nephropathies/genetics* ; Medicine, Chinese Traditional ; Kidney/pathology* ; Transforming Growth Factor beta/metabolism* ; Signal Transduction ; Epithelial-Mesenchymal Transition ; Smad Proteins/metabolism* ; Transforming Growth Factor beta1/metabolism* ; Diabetes Mellitus/genetics*

This study investigated the effect of multi-glycosides of Tripterygium wilfordii(GTW) on renal injury in diabetic kidney disease(DKD) rats through Nod-like receptor protein 3(NLRP3)/cysteine-aspartic acid protease-1(caspase-1)/gsdermin D(GSDMD) pyroptosis pathway and the mechanism. To be specific, a total of 40 male SD rats were randomized into the normal group(n=8) and modeling group(n=34). In the modeling group, a high-sugar and high-fat diet and one-time intraperitoneal injection of streptozotocin(STZ) were used to induce DKD in rats. After successful modeling, they were randomly classified into model group, valsartan(Diovan) group, and GTW group. Normal group and model group were given normal saline, and the valsartan group and GTW group received(ig) valsartan and GTW, respectively, for 6 weeks. Blood urea nitrogen(BUN), serum creatinine(Scr), alanine ami-notransferase(ALT), albumin(ALB), and 24 hours urinary total protein(24 h-UTP) were determined by biochemical tests. The pathological changes of renal tissue were observed based on hematoxylin and eosin(HE) staining. Serum levels of interleukin-1β(IL-1β) and interleukin-18(IL-18) were detected by enzyme-linked immunosorbent assay(ELISA). Western blot was used to detect the expression of pyroptosis pathway-related proteins in renal tissue, and RT-PCR to determine the expression of pyroptosis pathway-related genes in renal tissue. Compared with the normal group, the model group showed high levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), low level of ALB(P<0.01), severe pathological damage to kidney, and high protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01). Compared with the model group, valsartan group and GTW group had low levels of BUN, Scr, ALT, and 24 h-UTP and serum levels of IL-1β and IL-18(P<0.01), high level of ALB(P<0.01), alleviation of the pathological damage to the kidney, and low protein and mRNA levels of NLRP3, caspase-1, and GSDMD in renal tissue(P<0.01 or P<0.05). GTW may inhibit pyroptosis by decreasing the expression of NLRP3/caspase-1/GSDMD in renal tissue, thereby relieving the inflammatory response of DKD rats and the pathological injury of kidney.
Rats ; Male ; Animals ; Diabetic Nephropathies/genetics* ; Interleukin-18/metabolism* ; Glycosides/pharmacology* ; Tripterygium ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Rats, Sprague-Dawley ; Caspase 1/metabolism* ; Pyroptosis ; Uridine Triphosphate/pharmacology* ; Kidney ; Valsartan/pharmacology* ; RNA, Messenger/metabolism* ; Diabetes Mellitus

Objective To investigate the effect of 1, 25-(OH)₂-VitD3 (VitD3) on renal tubuleinterstitial fibrosis in diabetic kidney disease. Methods NRK-52E renal tubular epithelial cells were divided into control group (5.5 mmol/L glucose medium treatment), high glucose group (25 mmol/L glucose medium treatment) and high glucose with added VitD3 group (25 mmol/L glucose medium combined with 10^-8 mmol/L VitD3). The mRNA and protein expression of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in NRK-52E cells were detected by real-time quantitative PCR and Western blot analysis respectively. The expression and localization of Snail1, SMAD3 and SMAD4 were detected by immunofluorescence cytochemical staining. The binding of Snail1 with SMAD3/SMAD4 complex to the promoter of Coxsackie-adenovirus receptor (CAR) was detected by chromatin immunoprecipitation. The interaction among Snail1, SMAD3/SMAD4 and E-cadherin were detected by luciferase assay. Small interfering RNA (siRNA) was used to inhibit the expression of Snail1 and SMAD4, and the expression of mRNA of E-cadherin was detected by real-time quantitative PCR. SD rats were randomly divided into control group, DKD group and VitD3-treated group. DKD model was established by injection of streptozotocin (STZ) in DKD group and VitD3-treated group. After DKD modeling, VitD3-treated group was given VitD3 (60 ng/kg) intragastric administration. Control group and DKD group were given normal saline intragastric administration. In the DKD group and VitD3-treated group, insulin (1-2 U/kg) was injected subcutaneously to control blood glucose for 8 weeks. The mRNA and protein levels of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in renal tissues were detected by real-time quantitative PCR and Western blot analysis respectively. Immunohistochemistry was used to detect the expression and localization of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in renal tissue. Results Compared with the control group, the mRNA and protein expressions of Snail1, SMAD3, SMAD4 and α-SMA in NRK-52E cells cultured with high glucose and in DKD renal tissues were up-regulated, while E-cadherin expression was down-regulated. After the intervention of VitD3, the expression levels of Snail1, SMAD3, SMAD4, α-SMA and E-cadherin in the DKD model improved to be close to those in the control group. Chromatin immunoprecipitation showed that Snail1 and SMAD3/SMAD4 bound to CAR promoter IV, while VitD3 prevented Snail1 and SMAD3/SMAD4 from binding to CAR promoter IV. Luciferase assay confirmed the interaction among Snail1, SMAD3/SMAD4 and E-cadherin. After the mRNA of Snail1 and SMAD4 was inhibited by siRNA, the expression of E-cadherin induced by high glucose was up-regulated. Conclusion VitD3 could inhibit the formation of Snail1-SMAD3/SMAD4 complex and alleviate the renal tubulointerstitial fibrosis in DKD.
Animals ; Rats ; Cadherins/genetics* ; Diabetes Mellitus/pathology* ; Diabetic Nephropathies/pathology* ; Epithelial-Mesenchymal Transition ; Fibrosis/pathology* ; Glucose/pharmacology* ; Kidney/pathology* ; Rats, Sprague-Dawley ; RNA, Messenger ; RNA, Small Interfering ; Transforming Growth Factor beta1/metabolism* ; Vitamin D/pharmacology*

Lignans derived from Eucommia ulmoides Oliver (Eucommia lignans) inhibit the progression of inflammatory diseases, while their effect on the progression of diabetic nephropathy (DN) remained unclear. This work was designed to assess the function of Eucommia lignans in DN. The major constituents of Eucommia lignans were analyzed by UPLC-Q-TOF-MS/MS. The binding between Eucommia lignans and aldose reductase (AR) was predicted by molecular docking. Eucommia lignans (200, 100, and 50 mg·kg^-1) were used in model animals to evaluate their renal function changes. Rat glomerular mesangial cells (HBZY-1) were transfected with sh-AR, sh-AMPK, and oe-AR in the presence of high glucose (HG) or HG combined with Eucommia lignans to evaluate whether Eucommia lignans affected HG-induced cell injury and mitochondrial dysfunction through the AR/Nrf2/HO-1/AMPK axis. Eucommia lignans significantly attenuated the progression of DN in vivo. Eucommia lignans notably reversed HG-induced upregulation of inflammatory cytokines and mitochondrial injury, while downregulating the levels of Cyto c, caspase 9, AR, and NOX4 in HBZY-1 cells. In contrast, HG-induced downregulation of Nrf2, HO-1 and p-AMPKα levels were abolished by Eucommia lignans. Meanwhile, knockdown of AR exerted similar therapeutic effect of Eucommia lignans on DN progression, and AR overexpression reversed the effect of Eucommia lignans. Eucommia lignans alleviated renal injury through the AR/Nrf2/HO-1/AMPK axis. Thus, these findings might provide evidence for the use of Eucommia lignans in treating DN.
Animals ; Rats ; AMP-Activated Protein Kinases/genetics* ; Diabetes Mellitus ; Diabetic Nephropathies/prevention & control* ; Eucommiaceae/metabolism* ; Lignans/therapeutic use* ; Molecular Docking Simulation ; NF-E2-Related Factor 2/metabolism* ; Tandem Mass Spectrometry

This study investigated the protective effects of Moutan Cortex polysaccharides components(MCPC) on the renal tissues of diabetic nephropathy(DN) rats and explored their regulation effect on inflammatory response and oxidative stress. The DN rat model was induced by high-glucose and high-fat diet combined with streptozotocin(STZ), and then the rats were randomly divided into control group, model group, positive group and MCPC high(120 mg·kg~(-1)·d~(-1)), low(60 mg·kg~(-1)·d~(-1)) dose groups. After 12 weeks treatment, blood was taken from the orbit of the rats, and then they were sacrificed before the kidney tissues were collected. The serum and tissues were detected for related biochemical indicators and pathological changes of the kidney. Immunohistochemical methods were used to determine the expression of FN and ColⅣ in the kidney tissue of DN rats. Compared with the model group, blood glucose, serum creatinine, blood urea nitrogen and 24 h urine protein in the MCPC high-dose group were significantly reduced(P<0.01). The results of HE, PAS, Masson staining showed that glomerular basement membrane thickening, Bowman's capsule narrowing and inflammatory cell infiltration in DN rats were improved in the MCPC high-dose group; the activity of T-SOD and GSH-Px in serum significantly increased(P<0.001), and the expression level of FN significantly decreased(P<0.001). The high-dose MCPC treatment could effectively inhibit the abnormal expression of Col Ⅳ(P<0.001) and significantly reduce the levels of AGEs and RAGE in serum(P<0.001), the content of VCAM-1 and IL-1β in serum(P<0.001), and the levels of IL-1β mRNA in kidney tissue(P<0.001), but failed to effectively reduce VCAM-1 mRNA levels in kidney tissues. The high-dose MCPC could significantly improve pathological injury of renal tissue and related renal indicators in DN rats, and achieve renal protection in DN rats mainly by regulating oxidative stress and inflammatory factors.
Animals ; Diabetes Mellitus, Experimental/genetics* ; Diabetic Nephropathies/genetics* ; Drugs, Chinese Herbal ; Kidney ; Paeonia ; Polysaccharides/pharmacology* ; Rats

This study aimed to investigate the effects of geniposide(GP) on the expression of prokineticin(PK2) and prokineticin receptor 1(PKR1) in db/db mice with diabetic nephropathy(DN), so as to explore how the PK2 signaling pathway participated in the pathological changes of DN and whether GP exerted the therapeutic effect through this signaling pathway. Male mice were randomly divided into four groups, namely db/m, db/db, db/db+GP, and db/m+GP groups, with five in each group. The mice in the db/db+GP and db/m+GP groups were gavaged with 150 mg·kg~(-1) GP for eight successive weeks. Afterwards, all the mice were sacrificed and the renal tissues were embedded. The morphological changes in glomerulus and renal tubules were observed by Masson and PAS staining. The expression levels of PK2, PKR1, and Wilm's Tumor Protein 1(WT_1) in podocytes were detected by immunohistochemistry, and the protein expression levels of PK2 and PKR1 in mouse kidney by Western blot. The morphological results showed serious glomerular and tubular fibrosis(Masson), high glomerular and tubular injury score(PAS), increased glomerular mesangial matrix, thickened basement membrane, exfoliated brush border of renal tubules, decreased WT_1 in glomerular podocytes, and massive loss of podocytes in the db/db group. After administration with GP, the glomerular and tubular fibrosis was alleviated, accompanied by improved glomerular basement membrane and renal tubule brush edge, and up-regulated WT_1. As revealed by further protein detection, in the db/db group, the expression levels of PK2 and PKR1 and p-Akt/Akt ratio declined, whereas the ratio of Bax/Bcl-2 rose. Ho-wever, PKR2 and p-ERK/ERK ratio did not change significantly. After administration with GP, the PK2 and PKR1 expression was elevated, and p-Akt/Akt ratio was increased. There was no obvious change in PKR2, Bax/Bcl-2 ratio, or p-ERK/ERK ratio. All these have demonstrated that GP improves the renal damage in DN mice, and PK2/PKR1 signaling pathway may be involved in such protection, which has provided reference for clinical treatment of DN with GP.
Animals ; Diabetes Mellitus ; Diabetic Nephropathies/genetics* ; Iridoids ; Kidney ; Male ; Mice ; Signal Transduction

Pharmacology network was used to investigate the common key target and signaling pathway of Notoginseng Radix et Rhizoma in the protection against diabetic nephropathy(DN), diabetic encephalopathy(DE) and diabetic cardiomyopathy(DCM). The chemical components of Notoginseng Radix et Rhizoma were obtained through TCMSP database and literature mining, and SwissTargetPrediction database was used to predict potential targets of Notoginseng Radix et Rhizoma. The disease targets of DN, DE and DCM were obtained through OMIM and GeneCards databases. The overlapped targets of component targets and disease targets of DN, DE and DCM were obtained, and the network of "chemical component-target-disease" was established. The enriched GO and KEGG of the overlapped genes were investigated by using ClueGo plug-in with Cytoscape. At the same time, the PPI network was constructed through STRING database, and the common key targets for the treatment of three diseases by Notoginseng Radix et Rhizoma were obtained through topological parametric mathematical analysis by Cytoscape. A total of 166 chemical components and 835 component targets were screened out from Notoginseng Radix et Rhizoma. Briefly, 216, 194 and 230 disease targets of DN, DE and DCM were collected, respectively. And 54, 45 and 57 overlapped targets were identified when overlapping these disease targets with component targets of Notoginseng Radix et Rhizoma, respectively. Enrichment analysis indicated that the AGE-RAGE signaling pathway and FoxO signaling pathway were the common pathways in the protection of Notoginseng Radix et Rhizoma against DN, DE and DCM. Network analysis of the overlapped targets showed that TNF, STAT3, IL6, VEGFA, MAPK8, CASP3 and SIRT1 were identified as key targets of Notoginseng Radix et Rhizoma against DN, DE and DCM, the selected key targets were verified by literature review, and it was found that TNF, IL6, VEGFA, CASP3 and SIRT1 had been reported in the literature. In addition, there were the most compounds corresponding to the commom core target STAT3, indicating that more compounds in Notoginseng Radix et Rhizoma could regulate STAT3. This study indicated that Notoginseng Radix et Rhizoma potentially protected against DN, DE and DCM through regulating AGE-RAGE signaling pathway and FoxO signaling pathway and 7 common targets including TNF, STAT3, IL6, VEGFA, MAPK8, CASP3 and SIRT1. This study provided a reference for the research of "different diseases with same treatment" and also elucidated the potential mechanism of Notoginseng Radix et Rhizoma against DN, DE and DCM.
Brain Diseases ; Diabetes Mellitus ; Diabetic Cardiomyopathies/genetics* ; Diabetic Nephropathies/genetics* ; Humans ; Research Design ; Signal Transduction

OBJECTIVE: To explore the influence of long non-coding (lnc) RNA Gm15645 on the podocyte injury in mice with diabetic nephropathy. METHODS: Male db/db mice (with Type 2 diabetes) with a genetic background of C57BLKs/J and db/m mice (healthy) born in littermates were randomly divided into three groups. db/db group was injected with lncRNAGm15645 shRNA lentivirus with a podocyte-specific marker NPHS2; db/db blank group was injected with saline, and db/db control group was injected withnon-sense lentivirus. The results of PAS staining, pathological changes of renal tissue, relative expression of GSK-3beta, and podocin expression were compared. RESULTS: lncRNAGm15 645 was overexpressed and podocin was down-regulated in the lentivirus overexpressed group. Mesangial cell proliferation, mesangial matrix hyperplasia, thickened basement membrane, widely fused foot process, and podocyte injury were observed by PAS staining. The expression of Gm15645 in the db/db group was significantly lower than that of the db/db blank group and db/db control group (P< 0.05), while the expression of podocin was higher (P< 0.05). Gm15645 was co-stained with podocin in renal tissue, and the target gene was GSK-3beta. CONCLUSION lncRNAGm15645 may provide an early biomarker for the occurrence of podocyte injury in diabetic nephropathy. The mechanism may be related to the feedback regulation of GSK-3beta gene.
Animals ; Diabetes Mellitus, Type 2 ; Diabetic Nephropathies/genetics* ; Glycogen Synthase Kinase 3 beta ; Male ; Mice ; Podocytes ; RNA, Long Noncoding/genetics*

Adult ; Diabetic Nephropathies ; genetics ; pathology ; Disease Progression ; Female ; Humans ; Male ; Middle Aged ; Transcriptome ; genetics

Diabetic nephropathy (DN) is one of the common microvascular complications of diabetes mellitus. Renal fibrosis is closely related to the deterioration of renal function. The present study aimed to investigate protective effect of Taxus chinensis on high-fat diet/streptozotocin-induced DN in rats and explore the underlying mechanism of action. The rat DN model was established via feeding high fat diet for 4 weeks and subsequently injecting streptozotocin (30 mg·kg body weight) intraperitoneally. The rats with blood glucose levels higher than 16.8 mmol·L were selected for experiments. The DN rats were treated with Taxus chinensis orally (0.32, 0.64, and 1.28 g·kg) once a day for 8 weeks. Taxus chinensis significantly improved the renal damage, which was indicated by the decreases in 24-h urinary albumin excretion rate, blood serum creatinine, and blood urea nitrogen. Histopathological examination confirmed the protective effect of Taxus chinensis. The thickness of glomerular basement membrane was reduced, and proliferation of mesangial cells and podocytes cells and increase in mesangial matrix were attenuated. Further experiments showed that Taxus chinensis treatment down-regulated the expression of TGF-β1 and α-SMA, inhibited phosphorylation of Smad2 and Smad3. These results demonstrated that Taxus chinensis alleviated renal injuries in DN rats, which may be associated with suppressing TGF-β1/Smad signaling pathway.
Albumins ; Animals ; Blood Glucose ; metabolism ; Creatinine ; blood ; Diabetic Nephropathies ; blood ; drug therapy ; genetics ; urine ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Kidney ; drug effects ; metabolism ; Male ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Smad Proteins ; genetics ; metabolism ; Taxus ; chemistry ; Transforming Growth Factor beta1 ; metabolism