PURPOSE: The aim of this study was to examine the effects of all-trans retinoic acid (ATRA) on diabetic nephropathy. MATERIALS AND METHODS: We measured amounts of urinary albumin excretion (UAE) after administrating ATRA to Otsuka Long-Evans Tokushima Fatty (OLETF) rats. In order to understand the mechanism of action for ATRA, we administrated ATRA to examine its inhibitory action on the production of transforming growth factor-beta1 (TGF-beta1), protein kinase C (PKC), and reactive oxidative stress (ROS) in cultured rat mesangial cells (RMCs). RESULTS: After 16 weeks of treatment, UAE was lower in the ATRA-treated OLETF rats than in the non-treated OLETF rats (0.07+/-0.03 mg/mgCr vs. 0.17+/-0.15 mg/mgCr, p<0.01). After incubation of RMCs in media containing 30 or 5 mM of glucose, treatment with ATRA showed time- and dose-dependent decreases in TGF-beta1 levels and ROS. Moreover, ATRA treatment showed a dose-dependent decrease in PKC expression. CONCLUSION: ATRA treatment suppressed UAE and TGF-beta1 synthesis, which was mediated by significant reductions in PKC activity and ROS production. Our results suggest that ATRA has a potential therapeutic role for diabetic nephropathy.
Animals ; Diabetes Mellitus, Type 2/*complications ; Diabetic Nephropathies/*complications/*drug therapy/pathology ; Mesangial Cells/*metabolism ; Oxidative Stress/drug effects ; Rats ; Rats, Inbred OLETF ; Reactive Oxygen Species/metabolism ; Transforming Growth Factor beta1/analysis/pharmacology ; Tretinoin/*pharmacology/therapeutic use

OBJECTIVETo explore the effects and underlying mechanisms of Panax notoginoside (PNS) on the nephropathy in rats with type 1 diabetes.

METHODSA murine model of diabetic nephropathy was set up by an intravenous injection of streptozotocin (STZ). Wistar rats were randomly divided into 5 groups: the control group, the diabetic group (DM), the group treated with low-dosage PNS (PNS-L), the group treated with high-dosage PNS (PNS-H) and the group treated with catopril. Rats in the PNS-L and PNS-H groups were given different dosages of PNS while rats in the catopril group were given catopril through gastrogavage every day for the next four consecutive weeks. Serum creatinine (Cr) levels, endogenous creatinine clearance rate (CCr), and 24-h urinary microalbumin (UAlb) were examined and calculated. Meanwhile, immunohistochemistry was applied to determine the expression of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-7 (BMP-7) in the kidney tissue.

RESULTSThe levels of Cr, Ccr, and UAlb were all elevated significantly in the DM group (P<0.01). The expression of VEGF protein was increased but BMP-7 protein was decreased in the kidney tissue (P<0.01). However, the above items decreased in the PNS-L, PNS-H and catopril groups compared with the DM group (P<0.05, P<0.01). In the PNS-L, PNS-H and catopril groups, the expression of VEGF protein was decreased but BMP-7 protein was increased in the kidney tissue (P<0.05, P<0.01).

CONCLUSIONPNS shows protective effects on the kidney in type 1 diabetic rats at the early stage. The protective mechanism might be closely related to its role of inhibiting the expression of VEGF protein and enhancing the expression of BMP-7 protein in the kidney.

Animals ; Body Weight ; drug effects ; Bone Morphogenetic Protein 7 ; metabolism ; Diabetes Mellitus, Type 1 ; complications ; drug therapy ; pathology ; physiopathology ; Diabetic Nephropathies ; complications ; drug therapy ; pathology ; physiopathology ; Hypertrophy ; Immunohistochemistry ; Kidney ; drug effects ; metabolism ; pathology ; Kidney Function Tests ; Male ; Panax ; chemistry ; Phytotherapy ; Plant Extracts ; pharmacology ; therapeutic use ; Proteinuria ; complications ; drug therapy ; pathology ; physiopathology ; Rats ; Rats, Wistar ; Vascular Endothelial Growth Factor A ; metabolism

PURPOSE: Diabetic nephropathy is a serious complication of type 2 diabetes mellitus, and delaying the development of diabetic nephropathy in patients with diabetes mellitus is very important. In this study, we investigated inflammation, oxidative stress, and lipid metabolism to assess whether curcumin ameliorates diabetic nephropathy. MATERIALS AND METHODS: Animals were divided into three groups: Long-Evans-Tokushima-Otsuka rats for normal controls, Otsuka-Long-Evans-Tokushima Fatty (OLETF) rats for the diabetic group, and curcumin-treated (100 mg/kg/day) OLETF rats. We measured body and epididymal fat weights, and examined plasma glucose, adiponectin, and lipid profiles at 45 weeks. To confirm renal damage, we measured albumin-creatinine ratio, superoxide dismutase (SOD), and malondialdehyde (MDA) in urine samples. Glomerular basement membrane thickness and slit pore density were evaluated in the renal cortex tissue of rats. Furthermore, we conducted adenosine monophosphate-activated protein kinase (AMPK) signaling and oxidative stress-related nuclear factor (erythroid-derived 2)-like 2 (Nrf2) signaling to investigate mechanisms of lipotoxicity in kidneys. RESULTS: Curcumin ameliorated albuminuria, pathophysiologic changes on the glomerulus, urinary MDA, and urinary SOD related with elevated Nrf2 signaling, as well as serum lipid-related index and ectopic lipid accumulation through activation of AMPK signaling. CONCLUSION: Collectively, these findings indicate that curcumin exerts renoprotective effects by inhibiting renal lipid accumulation and oxidative stress through AMPK and Nrf2 signaling pathway.
Albuminuria ; Animals ; Anti-Inflammatory Agents, Non-Steroidal/*therapeutic use ; Curcumin/*pharmacology ; Diabetes Mellitus, Type 2/*metabolism/urine ; Diabetic Nephropathies/complications/*drug therapy/metabolism/pathology ; Gene Expression/drug effects ; Inflammation ; Kidney/drug effects/metabolism/physiopathology ; Kidney Glomerulus/metabolism/physiopathology ; Lipid Metabolism/*drug effects ; Male ; Malondialdehyde/metabolism/urine ; Oxidative Stress/*drug effects ; Rats ; Rats, Inbred OLETF ; Rats, Long-Evans ; Superoxide Dismutase/metabolism

Diabetic nephropathy is the most serious complication in diabetes mellitus. It is known that oxidative stress and inflammation play a central role in the development of diabetic nephropathy. In this study, we investigated that ferulic acid (FA) known as anti-oxidative agent could effect on diabetic nephropathy by anti-oxidative and anti-inflammatory mechanism. We examined the effects of FA in obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and non-diabetic control Long-Evans Tokushima Otsuka (LETO) rats. We treated FA to experimental rats from 26 to 45 weeks of age. We evaluated ACR, MDA and MCP-1 in 24 h urine and examined renal histopathology and morphologic change in extracted kidneys from rats. Also, we evaluated the ROS production and MCP-1 levels in cultured podocyte after FA treatment. In the FA-treated OLETF rats, blood glucose was significantly decreased and serum adiponectin levels were increased. Urinary ACR was significantly reduced in FA-treated OLETF rats compared with diabetic OLETF rats. In renal histopathology, FA-treated OLETF rats showed decreased glomerular basement membrane thickness, glomerular volume, and mesangial matrix expansion. FA treatment decreased oxidative stress markers and MCP-1 levels in 24 h urine of rats and supernatants of cultured podocyte. In conclusion, it was suggested that FA have protective and therapeutic effects on diabetic nephropathy by reducing oxidative stress and inflammation.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/*therapeutic use ; Antioxidants/*therapeutic use ; Cells, Cultured ; Chemokine CCL2/genetics/urine ; Collagen/analysis ; Coumaric Acids/*therapeutic use ; Diabetes Mellitus, Type 2/*complications ; Diabetic Nephropathies/*complications/*drug therapy/pathology ; Gene Expression/drug effects ; Kidney/drug effects/pathology ; Malondialdehyde/urine ; Podocytes/drug effects/metabolism ; Rats ; Rats, Inbred OLETF ; Reactive Oxygen Species/metabolism ; Transforming Growth Factor beta1/analysis

OBJECTIVETo evaluate the renal protective effect of Tangshenkang Granule () in a rat model of diabetic nephropathy (DN).

METHODSForty male Sprague-Dawley rats were randomly divided into control, DN, Tangshenkang and benazepril groups. DN model was established in the rats of DN, Tangshenkang and benazepril groups. Tangshenkang Granule solution and benazepril hydrochloride solution were intragastrically administered daily to the rats in the Tangshenkang and benazepril groups for 8 weeks, respectively. Urinary albumin and creatinine were detected. The albumin/creatinine (ACR) was calculated in addition to 24 h urinary protein (24-h UPr), serum creatinine (Scr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and creatinine clearance rate (Ccr). Right kidneys were harvested for pathological observation using periodic acid-silver methenamine-Masson staining. The average glomerular diameter (DG), average glomerular (AG) and mesangial areas (AM) were measured. The thickness of glomerular basement membrane (TGBM) was detected using transmission electron microscope.

RESULTSCompared with rats in the control group, rats in the DN group showed significantly decreased body weight, increased hypertrophy index, 24-h urinary volume, 24-h UPr, ACR, Scr, BUN, Ccr, blood lipids as well as renal pathological indices including DG, AG, AM, AM/AG and TGBM (P <0.05). Compared with the DN group, the weights of rats in the Tangshenkang and benazepril groups were significantly increased, and the renal hypertrophy indices were significantly decreased (P <0.05). The 24-h urinary volumes, ACR, 24-h UPr, Scr, BUN, Ccr, LDL, DG, AG, AM and TGBM were obviously decreased (P <0.05). Compared with the benazepril group, the Tangshenkang group showed significantly decreased levels of ACR, 24-h UPr, AG and AM (P <0.05).

CONCLUSIONSTangshenkang Granule decreased the urinary protein, attenuated the high glomerular filtration rate and improved lipid metabolism in DN rats, and prevented further injury induced by diabetic nephropathy.

Albuminuria ; complications ; Animals ; Basement Membrane ; drug effects ; metabolism ; Blood Urea Nitrogen ; Body Weight ; drug effects ; Creatinine ; blood ; urine ; Diabetic Nephropathies ; blood ; drug therapy ; physiopathology ; urine ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Hypertrophy ; Kidney Function Tests ; Kidney Glomerulus ; drug effects ; pathology ; physiopathology ; Lipid Metabolism ; drug effects ; Lipids ; blood ; Male ; Rats, Sprague-Dawley

AIMTo assess the effects of the alpha-glucosidase inhibitor Sangzhi (Ramulus mori, SZ) on the relief of diabetic symptoms of hyperglycemia and the prevention of its late complications in alloxan diabetic rats with high-calorie chow.

METHODSThe aqueous extract of Sangzhi was given orally to alloxan diabetic rats for 15 days. The hyperglycemic symptoms were observed. The blood glucose, lipid levels and the nephrotic representations were measured.

RESULTSWhen alloxan diabetic rats on high-calorie chow were treated with SZ, the hyperglycemic symptoms were improved, the blood lipid levels were improved, the ratio of kidney over body weight and the blood N-acetyl-beta-D-glucosaminidase (NAG) activity were lowered. The degree of renal pathological changes was significantly reduced.

CONCLUSIONSZ may be useful for treating diabetes and its complications.

Acetylglucosaminidase ; blood ; Animals ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; complications ; drug therapy ; metabolism ; Diabetic Nephropathies ; etiology ; metabolism ; prevention & control ; Disease Models, Animal ; Enzyme Inhibitors ; therapeutic use ; Glycoside Hydrolase Inhibitors ; Hypoglycemic Agents ; isolation & purification ; pharmacology ; therapeutic use ; Kidney ; pathology ; Male ; Morus ; chemistry ; Plants, Medicinal ; chemistry ; Rats ; Rats, Wistar ; Triglycerides ; blood ; alpha-Glucosidases ; isolation & purification

We aimed to elucidate the effect of bilirubin on dyslipidemia and nephropathy in a diabetes mellitus (DM) type I animal model. Sprague-Dawley rats were separated into control, DM, and bilirubin-treated DM (Bil) groups. The Bil group was injected intraperitoneally with 60 mg/kg bilirubin 3 times per week and hepatoma cells were cultured with bilirubin at a concentration of 0.3 mg/dL. The Bil group showed lower serum creatinine levels 5 weeks after diabetes onset. Bilirubin treatment also decreased the amount of mesangial matrix, lowered the expression of renal collagen IV and transforming growth factor (TGF)-beta1, and reduced the level of apoptosis in the kidney, compared to the DM group. These changes were accompanied by decreased tissue levels of hydrogen superoxide and NADPH oxidase subunit proteins. Bilirubin decreased serum total cholesterol, high-density lipoprotein cholesterol (HDL-C), free fatty acids, and triglycerides (TGs), as well as the TG content in the liver tissues. Bilirubin suppressed protein expression of LXRalpha, SREBP-1, SCD-1, and FAS, factors involved in TG synthesis that were elevated in the livers of DM rats and hepatoma cells under high-glucose conditions. In conclusion, bilirubin attenuates renal dysfunction and dyslipidemia in diabetes by suppressing LXRalpha and SREBP-1 expression and oxidative stress.
Animals ; Bilirubin/pharmacology/*therapeutic use ; Cell Line, Tumor ; Creatine/blood ; Diabetes Mellitus, Experimental/chemically induced/complications/*pathology ; Diabetic Nephropathies/*drug therapy/etiology ; Disease Models, Animal ; Kidney/pathology ; Lipoproteins, HDL/blood ; Liver/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; NADPH Oxidase/metabolism ; Orphan Nuclear Receptors/antagonists & inhibitors/genetics/metabolism ; Oxidative Stress/drug effects ; Rats ; Rats, Sprague-Dawley ; Reactive Oxygen Species/metabolism ; Streptozocin/toxicity ; Triglycerides/analysis/*biosynthesis/blood