Kidney Weight/body Weight Research Articles

Uncovering the Nephroprotective Mechanism of Caffeic Acid in Renal Tubulointerstitial Fibrosis through Network Pharmacology Analysis

Background: Renal tubulointerstitial fibrosis (RTF) is a progressive kidney condition characterized by the formation of fibrotic tissue. Caffeic acid (CA), a key component of the medicinal plant Antirhea borbonica, shows promise as a potential treatment for renal fibrosis. Here, we investigated the nephroprotective effect of CA in RTF and its underlying mechanisms. Methods: RTF was induced in rats through unilateral ureteral obstruction (UUO), followed by intraperitoneal administration of CA for 5 days. We assessed kidney weight/body weight (KW/BW) ratio, serum creatinine (Scr), blood urea nitrogen (BUN), 24-h urine protein (UP), and performed histological examinations. We also analyzed the expression of fibrosis-related proteins. Genes associated with RTF and CA were identified using public databases. A protein-protein interaction (PPI) network and molecular docking studies were conducted. Results: CA treatment significantly reduced the KW/BW ratio, levels of Scr, BUN, and 24-h UP, indicating improved kidney function in UUO-induced RTF rats. Histological examination revealed reduced fibrotic changes. CA administration also led to decreased collagen deposition and downregulation of fibrosis-related protein expression. CA administration also led to decreased collagen deposition and downregulation of fibrosis-related protein expression. The PPI network analysis showed significant differential expression of 13 genes between the fibrosis and normal groups. Notably, EGFR and MAPK14 were strongly associated with CA, and CA treatment downregulated EGFR and MAPK14 protein expression in UUO rats. Conclusion: CA exhibits substantial nephroprotective effects in UUO-induced RTF rats by modulating key genes EGFR and MAPK14, and MAPK signaling pathway.

307-OR: Activation of Mitochondrial Activities by Pyruvate Kinase M2 (PKM2) in Podocytes Improved Glomerular Metabolism and Diabetic Nephropathy

Diabetic nephropathy (DN) is the result of systemic and local changes in metabolism and hemodynamics. We have found that the elevation of glycolytic enzymes, such as pyruvate kinase M2 (PKM2) in the renal glomeruli is correlated with preservation of renal function in human type 1 and type 2 diabetes. A small-molecule PKM2 activator, TEPP46, prevented or reversed glomerular pathology in diabetic mice of chronic duration. Mice with PKM2 overexpression specifically in podocytes (PPKM2Tg) were generated, which after 7 months of diabetes induced by streptozotocin, exhibited significantly lower albumin-creatinine ratio (ACR), kidney weight-body weight ratio, and glomeruli pathology such as reduced glomeruli size, mesangial expansion, and basement membrane thickness compared to diabetic WT mice. Furthermore, the glomeruli of diabetic PPKM2Tg mice exhibited lower expressions of fibrotic (FN, TGFβ1 and Col4a) and oxidative stress (p47phox, NOX2 and NOX4) genes compared to WT diabetic mice. Interestingly, the decreased expression of endothelial-trophic genes and mitochondrial-related genes were improved in the whole glomeruli of diabetic PPKM2Tg mice. Oxygen consumption rate (OCR) of glomeruli as measured by Seahorse showed significant improvement in diabetic PPKM2Tg mice versus WT mice (p < 0.05). In vitro studies showed that the activation of PKM2 in mouse podocyte cell line by TEPP-46 decreased high glucose-induced ROS production, improved mitochondrial membrane potential (MMP) by increased the level of mitochondrial OCR and enhanced glycolytic rate. Furthermore, PKM-knockdown stable podocyte cell line, mimicking diabetic conditions, showed dramatical decline of OCR and glycolytic rate. These results showed that PKM2 specific overexpression in podocytes can significantly reduce diabetes-induced mitochondrial abnormalities and oxidative stress in the whole glomeruli, and delay the progression of diabetic nephropathy. Disclosure J. Fu: None. T. Shinjo: None. R. St-Louis: None. Q. Li: None. K. Park: None. H. Yokomizo: None. Y. Zaitsu: Employee; Self; Sunstar Group. M. Yu: None. I. Wu: None. H. Shah: None. G.L. King: Research Support; Self; Janssen Pharmaceuticals, Inc.

231-OR: ADA Presidents' Select Abstract: Pyruvate Kinase M2 Overexpression in Podocytes Ameliorates Nephropathy in Diabetic Mice

Elevated expression of pyruvate kinase isoform M2 (PKM2) in the renal glomeruli of people with diabetes is associated with protection from nephropathy even with hyperglycemia. Furthermore, systemic use of PKM2 activators (TEPP46) can prevent or reverse glomerular pathology in diabetic mice. To determine specifically the role of PKM2 in the development or progression of diabetic glomerulopathy, we generated transgenic mice overexpressing PKM2 specific targeted to the podocytes (PPKM2Tg mice) driven by the podocin promoter. Analysis of the glomeruli from these mice showed 1.5-fold increases in mRNA and protein levels without changes in PKM1, compared to wild type (WT) littermates (p<0.05). Pyruvate kinase (PK) activity in the glomeruli of the PPKM2Tg mice was increased by 40% compared to those in WT mice (p<0.05). Diabetes was induced in eight-week-old WT and PPKM2Tg mice by streptozotocin (STZ) and maintained with sustained glucose levels >400mg/dL for 7 months. Diabetic PPKM2Tg mice showed significantly lower urinary albumin-creatinine ratio (ACR) and kidney weight-body weight ratios (p<0.05) compared to diabetic WT mice even with similar hyperglycemia. PK activity was lowered in the glomeruli of diabetic WT mice by 30%, whereas levels in diabetic PPKM2Tg mice were comparable to nondiabetic WT mice. For renal pathology, diabetic PPKM2Tg mice exhibited smaller glomeruli compared to diabetic WT mice. Similarly, expressions of inflammatory genes including TNFα and MCP-1, and fibrotic genes including fibronectin and TGF-β1 were downregulated in the glomeruli of diabetic PPKM2Tg mice compared to diabetic WT mice. In contrast, mitochondrial genes such as PGC-1α, Opa1, and cytochrome b in the glomeruli of diabetic PPKM2Tg mice were significantly upregulated as compared to diabetic WT mice. These findings strongly suggest that upregulation or activation of PKM2 and glycolysis may improve mitochondrial function in podocytes and prevent the progression of diabetic nephropathy. Disclosure T. Shinjo: None. R. St-Louis: None. J. Fu: None. K. Park: None. Q. Li: None. H. Yokomizo: None. M. Yu: None. H. Wang: None. A. Kannt: Employee; Self; Sanofi. T. Sadowski: Employee; Self; Sanofi-Aventis Deutschland GmbH. G.L. King: Research Support; Self; Sanofi. Funding National Institutes of Health; Sanofi

Adiponectin improves diabetic nephropathy by inhibiting necrotic apoptosis.

IntroductionThis study aimed to investigate the effect of adiponectin (Apn) on necrotic apoptosis (Nec) in vitro and in vivo to clarify the possible role of Apn in the pathogenesis of diabetic nephropathy (DN).Material and methodsRat glomerular endothelial (RGE) cells were treated with high glucose (HG, 30 mmol/l) for 24 h and the effects of Apn on cell viability, RIP1 and RIP3 expression and p-p38MAPK activation were assayed by CCK-8, immunofluorescence and western blot. Then a streptozotocin (STZ)-induced DN rat model was established. The body weight, left kidney weight, left kidney weight/body weight (KW/BW), creatinine clearance rate (Ccr), 24 h urine protein and blood glucose were recorded. The expression of RIP1, RIP3 and p-p38MAPK in renal tissues was examined by immunohistochemistry and western blot.ResultsTreatment of RGE cells with HG induced significant cytotoxicity and increased expression levels of RIP1, RIP3 and p-p38MAPK, which were abrogated by Apn in a concentration-dependent manner. In vivo, compared with the control group, the Ccr, 24 h urine protein and the blood glucose level of the rats in the model group were significantly increased, effects which were abrogated by Apn intervention. Moreover, the expression levels of RIP1, PIP3 and p-p38MAPK were also significantly increased in the model group, effects which were canceled by Apn intervention.ConclusionsApn can alleviate the inflammatory response and damage of DN by inhibiting Nec via p-p38MAPK signaling.

Protective effects of tacrolimus on podocytes in early diabetic nephropathy in rats.

The aim of the present study was to investigate the protective effect of tacrolimus on early podocyte damage in rats with diabetic nephropathy (DN). A total of 38 normal male Sprague‑Dawley rats were randomly divided into four groups: Normal control group (group N; n=8), DN group (n=10), tacrolimus (FK506) treatment group (group F; n=10), benazepril (Lotensin) treatment group (group L; n=10). The rats in groups DN, F and L were administered with streptozotocin (STZ; 60mg/kg) by intraperitoneal injection to establish the diabetic rat model. After 4weeks, the diabetic rat model was established, and rats in the different groups were administered intragrastically with the respective drugs. Blood glucose (BS), body weight (BW) and 24‑h urine protein were detected every 4weeks, serum creatinine (SCr), blood urea nitrogen (BUN) and kidney weight/body weight (KW/BW) were measured at the end of the 8weeks of drug treatment. Renal pathological changes were observed under a light microscope and electron microscope. Expression of nephrin, which is a podocyte‑specific marker, was detected using western blot analysis. The results showed that the levels of SCr, BUN, KW/BW and 24‑h urine protein in groups D, F and L were significantly higher, compared with those in group N (P<0.05). No significant differences were found between groups F and L for the above indicators, with the exception of BS. However, all indices were significantly lower, compared with those in group DN (P<0.05). Renal pathological expression was normal in group N under light microscopy. There were significant increases in the glomerular volume, proliferative mesangial cells, width of the mesangial area and thickness of the basement membrane in group DN, however, all the above pathological characteristics were reduced in groups F and L, compared with group DN (P<0.05). No significant difference was found between groups F and L. A widened glomerular basement membrane, and disorder, widening and fusion of podocyte processes were observed under the electron microscope in group DN, however, these were reduced in groups F and L, compared with group DN (P<0.05). The results of the western blot analysis showed that the expression of nephrin decreased by 60.1% in group DN, compared with group N, and significant recovery in the expression of nephrin was observed in groups F and L (P<0.05). Tacrolimus reduced urinary protein and slowed the progression of DN, partially by recovering the protein expression of nephrin in the renal tissue of diabetic rats, and maintaining the integrity of the structure and function of podocytes.

Therapeutic evaluation of rutin in two-kidney one-clip model of renovascular hypertension in rat

AimThe current investigation, designed to investigate the role of rutin in two-kidney one-clip (2K1C) induced renovascular dysfunction associated with hypertension in rat. Main methodsThe renovascular hypertension was developed by the application of vascular clip on left renal artery in rats; the right kidney was kept as such throughout the experimental protocol. The rutin (200 and 300mg/kg; p.o.) and aliskiren (50mg/kg; p.o.) were administered for 9 consecutive days. The battery of pathophysiological tests i.e., systolic pressure, diastolic pressure and heart rate were performed to assess the anti-hypertensive effect of rutin. In addition, changes of kidney weight/body weight (KW/BW) ratio along with plasma renin content and renal tissue biomarkers i.e., thiobarbituric acid reactive substance (TBAR) and reduced glutathione (GSH) levels were estimated. Key findingsThe administration of rutin significantly (P<0.05) attenuated the 2K1C of left kidney induced elevated systolic and diastolic pressure in a dose dependent manner. In addition, it also reduces the ratio of KW/BW along with a decrease in plasma renin content, tissue TBARS and increase the GSH levels. There were no significant changes observed in heart rate. Similar results were observed in aliskiren treated group. SignificanceThe anti-hypertensive effect of rutin may be a useful herbal medicine for the management of hypertension due to its potential free radical scavenging, inhibition of lipid peroxidation and plasma renin inhibitory action.

Benefical therapeutic effect of Chinese Herbal Xinji'erkang formula on hypertension-induced renal injury in the 2-kidney-1-clip hypertensive rats.

Increase in evidence shows that the role of kidney injury in hypertension is important. Xinji'erkang (XJEK), a Chinese herbal formula, has been identified as an effective preparation in the treatment of coronary heart disease and myocarditis. We have previously demonstrated that XJEK attenuate oxidative stress and hypertension target organ damage. The aim of this study was to assess the renal protective function of XJEK. Two Kidney One Clip (2K1C) model was adopted to induce hypertension in rats. We submitted male Sprague Dawley (150-180) g rats to either renal artery clipping or sham operation. Renal hypertension was established after four weeks of surgery. Rats were randomized divided into the four groups: sham-operated group (Sh-Op) (n=10), two-kidney, one-clip hypertension group (2K1C) (n=10), Xinji'erkang treatment group (XJEK) (n=10) and Fosinopril (n=10) treatment group. Drugs were administered orally daily for four weeks. Systolic pressures were measured every week using the tail-cuff apparatus. 24h before death, urine samples were collected for detect of urinary proteins. The kidney weight (KW) index was expressed as kidney weight/body weight (KW/BW). The histological changes were investigated by hematoxylin and eosin and Van Gieson staining. Immunohistochemical assay was employed to observe the intra-renal transforming growth factor-β1 (TGF-β1) protein expression. Serum creatinine (SCR) and blood urea nitrogen (BUN) were assayed by automatic biochemical analyzer. ELISA kit was used to assay Angiotensin II (Ang II) and TGF-β1 content in serum. Administration of XJEK markedly alleviated the rise in blood pressure and declined LKW/BW ratio. Histo-pathological injuries including hypertrophic glomerular, glomerular sclerosis, glomerular and interstitial fibrosis were attenuated. XJEK also decreased SCR, BUN, urinary proteins in 24h urine, serum Ang II and TGF-β1 concentrations and the intra-renal TGF-β1 protein expression. XJEK therapy in the 2K1C hypertensive rats affects the rise in blood pressure and ameliorates the severity of kidney injury. The protective effect is most likely due to the ability of XJEK to affect the Renin-Angiotensin-Aldosterone System (RAAS) and the TGF-β systems.

Effects of angiotensin-II receptor blockers on β-catenin expression in a rat model of experimental streptozotocin-induced early-stage of diabetic nephropathy

ObjectiveDiabetic nephropathy (DN) is one of the most common causes of end-stage renal failure. The pathogenesis of progressive renal injury is multifactorial and the mechanism by which hyperglycemia causes microangiopathy is still poorly understood. The WNT pathway is activated in DN and regulating β-catenin protein levels is referred to as the canonical Wnt/β-catenin pathway. Because the renin angiotensin system has been reported to be an important contributory factor in the pathophysiology of DN, exogenous administration of angiotensin II receptor antagonist may be beneficial in counteracting some biochemical or functional changes of DN. The aim of the study was to determine the β-catenin expression and the possible protective effects of irbesartan, an angiotensin II type 1 receptor blocker (ARB) in a rat model of streptozotocin(STZ)-induced diabetic nephropathy. MethodsSTZ-induced DN in rats was assessed biochemically by measuring urine volume, protein and creatinine clearance as well as Kidney weight/body weight (KW/BW) and the index of mesangial expansion. Three groups of male Sprague-dawley rats were used. The first group consisted of non-diabetic control rats (control). The second group was the untreated diabetic rats(STZ+vehicle). The third group consisted of diabeti rats treated with irbesartan, 50 mg/kg for 12 weeks (STZ+irbesartan). Immunohistochemical stainings and real time PCR for β-catenin were performed in renal cortex of rat modals. ResultsMarked hyperglycemia, polyuria, proteinuria, renal hypertrophy, mesangial matrix expansion and glomerular hyperfiltration were observed in STZ diabetic rats. The levels of microalbuminuria and KW/BW in the STZ+irbesartan group were lower than those in the STZ+vehicle group (P<0.05). The up-regulated immunostaining and mRNA expression of β-catenin were decreased in renal cortic of the Irbesartan-treated diabetic group, but there was no significant difference compared to the untreated diabetic group. ConclusionThe data suggest that irbesartan ameliorates proteinuria and renal hypertrophy, charactered damages of STZ-induced early-stage DN in rats, but its effective drug target is not to inhibit the up-regulated expressions of β-catenin.

Effects of Oligomeric Grape Seed Proanthocyanidins on Heart, Aorta, Kidney in DOCA‐Salt Mice: Role of Oxidative Stress

Growing experimental and clinical data highlights the important roles of increased reactive oxygen species production in cardiovascular remodeling (CR). Oligomeric grape seed proanthocyanidins (GSPs) have been shown to be potent antioxidants and free radical scavengers. Mice were treated with DOCA-salt to induce CR and were given distilled water or oligomeric GSPs for 4 weeks. The heart weight (HW) index and kidney weight (KW) index were expressed as heart weight/body weight (HW/BW) and kidney weight/body weight (KW/BW); the histological changes were investigated by hematoxylin and eosin and Van Gieson staining.The endothelial-dependent vasodilation function induced by acetylcholine was investigated in isolated thoracic aorta ring. Colorimetric analysis was used to assay superoxide dismutase (SOD) activity, malondialdehyde (MDA) content and nitric oxide (NO) content in serum and hydroxyproline content in cardiac tissue. Administration of GSPs markedly alleviated the elevation of HW/BW ratio, KW/BW ratio and cross-sectional area of cardiomyocytes, decreased collagen deposition in heart and attenuated histopathology injury, and improves endothelial-dependent aorta ring relaxation in vitro accompany by increasing of NO content in serum. Meanwhile, treatment with GSPs significantly ameliorated oxidative stress via increasing SOD activities and decreasing MDA formation. These findings suggest that administration of GSPs has the potential to attenuate DOCA-salt induced CR and KH and preserve NO activity and endothelial function, which mechanism may contribute to its antioxidant characteristic, at least in part.

Toxic effect of TiO&lt;SUB&gt;2&lt;/SUB&gt; nanoparticles against human lung cancer cell line A549

Objective To investigate the protective effect of compound Xueshuantong capsule against damage of diabetic nephropathy in rat diabetic model.Methods Male SD rats were given intraperitoneal injection of streptozotocin(STZ)at 60mg/kg, and diabetic rat model was deemed successfully induced when the blood glucose level≥16.7mmol/L 3days after injection.Thirty model rats were randomly divided into the following 3groups equally:diabetic model group(DM),compound Xueshuantongcapsule group(XST),andα-lipoic acid treatment group(ALA).Another 10normal rats served as normal control group(NG).The body weight,blood glucose,blood fat,kidney weight/body weight(KW/BW),24h-urinary protein excretion,urea nitrogen,and serum creatinine were observed and compared between different groups after 12weeks’treatment.The ultrastructure changes of kidney were observed by electron microscopy and light microscope.Results Compared with NG group,rats in DM group had a higher 24h-urinary protein excretion(P0.05),and those in XST group and ALA group had a significantly lower one compared with the DM group(P0.05).Compared with NG group,rats in the other 3groups had a higher KW/BW,with significant difference found between DM group and XST group(P0.05).Electron microscopic results showed uneven glomerular basement membrane thickening, foot process integration,and mesangial cell proliferation in the model group;all the above changes were improved in the XST and ALA groups.Conclusion Compound Xueshuantongcapsule can lower the 24h-urinary protein secretion,decrease KW/BW,and improve the structure of glomerular basement membrane,thus exerting renal protective effect in diabetic rats.

Effect of berberine on expression of transforming growth factor-β1 and type Ⅳ collagen proteins in mesangial cells of diabetic rats with nephropathy

To explore the effect and mechanism of berberine on diabetic nephropathy in experimental rats. The rat model of diabetic nephropathy was induced by injection of streptozocin (STZ). The rats were divided into 6 groups: control group, model group, 3 berberine treatment groups and Xiaoke Wan (XKW) treatment group. The fasting blood glucose (FBG), kidney weight/body weight (KW/BW), blood urea nitrogen (BUN), creatinine (Cr) and urinary protein (Upro) were tested 8 weeks later. The expression of transforming growth factor-beta1 (TGF-beta1) and type IV collagen (IV-C) proteins in renal tissue of diabetic rats with nephropathy were observed by optical micrography. Berberine could reduce the levels of FBG, KW/BW, BUN, Cr, Upro and the expression of TGF-beta1 and IV-C proteins in renal tissue of diabetic rats with nephropathy. Berberine may protect renal function and slow down the progression of diabetic nephropathy in rats by suppressing the expression of TGF-beta1 and IV-C proteins in renal tissue.

Effect of Tongluo recipe on oxidative stress in kidneys of diabetic rats

Objective:To study the effect of two types of Tongluo recipe(ultrafine type and fine type) on the level of oxidative stress in kidneys of diabetic Sprague-Dawley rats.Methods: Experimental diabetes was induced by intraperitoneal injection of streptozotocin(60 mg/kg) in male Sprague-Dawley rats.One week after streptozotocin injection rats with blood glucose higher than 16.7 mmol/L were taken as diabetics.The study included the following 4 groups: normal control(NC),diabetes mellitus control(DMC),diabetics treated with ultrafine Tongluo recipe(DM+UT,1 g·kg-1·d-1),and diabetics treated with fine Tongluo recipe(DM+FT,1 g·kg-1·d-1).Four weeks after treatment,24 h urinary protein(24 h UP) and kidney weight/body weight(KW/BW) were detected as renal function indices;malondialdehyde(MDA) and antioxidant enzymes was examined with colorimetry;and NADPH oxidase subunits p47phox and p22phox mRNA were studied with real-time PCR.Results: Compared with the NC group,DMC group had significantly higher MDA,24 h UP,KW/BW,and glutathione peroxidase(GSH-Px) activity,and had significantly lower activity of total superoxide dismutase(TSOD).No significant difference was found in catalase(CAT) activity between the NC group and DMC group.Compared with the 2 Tongluo Recipe groups,the DMC group had significantly lower 24 h UP,KW/BW and MDA,and significantly higher activities of TSOD and GSH-Px,and no significant difference was found in their CAT activities.The effect of ultrafine type on 24 h UP,KW/BW,MDA,TSOD and GSH-Px was significantly greater than the fine type did.The expression of p47phox mRNA of NADPH oxidase in renal cortex group was significantly lower than that in the DMC group,and the latter was significantly higher than the 2 Tongluo of the NC recipe groups,and there was no significant difference between the 2 Tongluo recipe groups.There was no significant difference in p22phox mRNA expression between all the 4 groups.Conclusion: Tongluo recipe may improve the activities of antioxidant enzymes(including TSOD and GSH-Px),decrease p47phox expression,and therefore inhibit the oxidative stress in renal cortex of diabetic rats,reducing the early kidney injury.

Effect of activin A on tubulointerstitial fibrosis in diabetic nephropathy

The effect of activin A on tubulointerstitial fibrosis in diabetic nephropathy (DN) using streptozotocin (STZ)-induced diabetic rats and high glucose-cultured HK-2 cells was investigated. Male Wistar rats were randomized into a normal control group (NC) and diabetes mellitus group (DM). Diabetes was induced by i.p. injection of STZ. Six rats were respectively killed 4, 8, 12 and 16 weeks after model establishment in each group. The changes of kidney weight/bodyweight (KW/BW), urine albumin excretion rate (AER) and creatinine clearance rate (Ccr) were determined. The morphology of tubulointerstitium was observed by light microscopy. Further biochemical analysis was provided using immunohistochemistry and real-time polymerase chain reaction. The different parameters in high glucose-cultured HK-2 cells were monitored by western blotting or enzyme-linked immunosorbent assay (ELISA) and the intervention of rh-follistatin on them was investigated. Compared with the NC group, there was marked enlargement in the levels of KW/BW, AER, Ccr and interstitial fibrosis index, and the production of P-Smad2/3 and fibronectin in the DM group from 8 to 16 weeks. Activin betaA, mainly located in tubular epithelial cells, was significantly higher in the DM group than that in the NC group throughout the study periods. Follistatin was abundant in the NC group, but was diminished gradually in the DM group. High glucose may facilitate the synthesis of activin betaA, transforming growth factor (TGF)-beta, P-Smad2/3 and fibronectin in HK-2 cells while rh-follistatin inhibited them except TGF-beta. Activin A is involved in tubulointerstitial fibrosis in DN by inducing the production of fibronectin through Smad signal pathway.