Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0011881 (diabetic nephropathy)
 10,836 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oxidative stress has an important role in genesis of diabetic complications, especially diabetic nephropathy. The aim of the study was to assess correlations between increase of oxidative stress (OS) and the development of microalbuminuria (MA) in type 1 diabetic patients. We determined the oxidative status by measuring the level of superoxide dismutase (SOD-Minanui method), catalase (CAT-Aebi method), glutathione peroxidase (GPx-Fukuzawa method) and glutathione (GSH-Ellman method) in 87 type 1 diabetic patients (44 with normal urinary protein excretion-group A and 43 with MA-group B) and 38 nondiabetic matched controls, before and 24 hours after a test effort. The results of the study point out that a decreased in activity of SOD or in levels of GSH is associated with an increased MA in type 1 diabetic patients.
 ...
PMID:[Correlation between increase of oxidative stress and microalbuminuria in type-1 diabetic patients]. 1600 16

Hyperglycemia causes the autoxidation of glucose, glycation of proteins, and the activation of polyol metabolism. These changes accelerate generation of reactive oxygen species (ROS) and increases in oxidative chemical modification of lipids, DNA, and proteins in various tissues. Oxidative stress may play an important role in the development of complications in diabetes such as lens cataracts, nephropathy, and neuropathy. Glycation reactions, especially Maillard reactions, occur in vivo as well as in vitro and are associated with the chronic complications of diabetes mellitus and aging and age-related diseases by increases in oxidative chemical modification of lipids, DNA, and proteins. In particular, long-lived proteins such as lens crystallines, collagens, and hemoglobin may react with reducing sugars to form advanced glycation end products (AGEs). Recently, we found a novel type of AGE, named MRX, and we found that MRX is a good biomarker for detecting oxidative stress produced during Maillard reaction. We also examined in detail the role of lipid peroxidation reaction in hyperglycemia and found that hexanoyl modification formed by the reaction of oxidized lipids and proteins must be important for oxidative stress. Detailed analyses of the formation mechanism of hexanoyl lysine (HEL) moiety in proteins were conducted, and excretion of HEL into urine was quantified by using LC/MS/MS. Macrophages and neutrophils play an important role in oxidative stress during hyperglycemia, and we determined that oxidatively modified tyrosines are a good biomarker for formation of oxidative stress at an early stage. Immunochemical analyses by application of monoclonal antibodies specific to lipid hydroperoxide-modified proteins produced by polyunsaturated fatty acids including docosahexaenoic acid (DHA) in oxidative stress caused by hyperglycemia were conducted, and the relationship between glycation and lipid peroxidation reactions both by chemical and immunochemical approaches are discussed. Recently, we put much more focus on dietary antioxidants for prevention of diabetic complications. Curcuminoids, the main yellow pigments in Curcuma longa (turmeric), have been used widely and for a long time in the treatment of sprain and inflammation in indigenous medicine. Curcumin is the main component of turmeric, and two minor components are also present as the curcuminoids. Curcuminoids possess antioxidant activity. Protective effects of curcumin (U1) and one of its major metabolites, tetrahydrocurcumin (THU1), have been examined for development of diabetic cataract in 25% galactose-fed SD rats. Through detailed examination of protective mechanisms of THU1, it was found that THU1 showed that scavenger ROS not only formed during hyperglycemia, but also induced antioxidative enzymes including detoxification enzymes such as glutathine S-transferase. THU1 also showed significant increase of glutathione concentration in the cultured rat lens. Glutathione (gamma-glutamylcysteinyl glycine [GSH]) is thought to be an important factor in cellular function and defense against oxidative stress, and we found that dietary GSH suppresses oxidative stress in vivo in prevention of diabetic complications such as diabetic nephropathy and neuropathy.
 ...
PMID:Protective role of antioxidative food factors in oxidative stress caused by hyperglycemia. 1603 65

We have studied the effects of red wine on brain oxidative stress and nephropathy in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced in Wistar rats with a single intraperitonally injection of STZ (50 mg/kg). Two weeks before and four weeks after injection, red wine was given orally in both normal and diabetic rats. Blood samples were taken from the neck vascular trunk in order to determine the glucose, triglycerides, total cholesterol, HDL-cholesterol (HDL-c), atherogenic index (AI), total protein, blood urea nitrogen (BUN), creatinine, insulin, lipid peroxidation products, reduced glutathione (GSH) and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. As well, we estimated the lipid peroxidtion, GSH and SOD, GSH-Px and catalase activities in brain and renal homogenates, and the excretion of albumin, proteins and glucose in urine over 24 h period. The administration of STZ caused significant increases in levels of glycosuria, proteinuria, albuminuria, glycemia, total cholesterol and AI, as well as in lipid peroxidation products in the brain, plasma and kidney, whereas it decreased the GSH content and SOD, GSH-Px and catalase activities. Treatment with red wine significantly prevented the changes induced by STZ. These data suggested that red wine has a protective effect against brain oxidative stress, diabetic nephropathy and diabetes induced by STZ, as well as it protects against hypercholesterolemia and atherogenic risk.
 ...
PMID:Red wine prevents brain oxidative stress and nephropathy in streptozotocin-induced diabetic rats. 1620 32

Dicarbonyl and oxidative stress may play important roles in the development of diabetes complications, and their response to hyperglycemia could determine individual susceptibility to diabetic nephropathy. This study examines the relationship of methylglyoxal, 3-deoxyglucosone (3DG), and oxidative stress levels to diabetic nephropathy risk in three populations with diabetes. All subjects in the Overt Nephropathy Progressor/Nonprogressor (ONPN) cohort (n = 14), the Natural History of Diabetic Nephropathy study (NHS) cohort (n = 110), and the Pima Indian cohort (n = 45) were evaluated for clinical nephropathy, while renal structural measures of fractional mesangial volume [Vv(Mes/glom)] and glomerular basement membrane (GBM) width were determined by electron microscopy morphometry in the NHS and Pima Indian cohorts. Methylglyoxal and 3DG levels reflected dicarbonyl stress, while reduced glutathione (GSH) and urine 8-isoprostane (8-IP) measured oxidative stress. Cross-sectional measures of methylglyoxal production by red blood cells incubated in 30 mmol/l glucose were increased in nephropathy progressors relative to nonprogressors in the ONPN (P = 0.027) and also reflected 5-year GBM thickening in the NHS cohort (P = 0.04). As nephropathy progressed in the NHS cohort, in vivo levels of methylglyoxal (P = 0.036), 3DG (P = 0.004), and oxidative stress (8-IP, P = 0.007 and GSH, P = 0.005) were seen, while increased methylglyoxal levels occurred as nephropathy progressed (P = 0.0016) in the type 2 Pima Indian cohort. Decreased glyceraldehyde-3-phosphate dehydrogenase activity also correlated with increased methylglyoxal levels (P = 0.003) in the NHS cohort. In conclusion, progression of diabetic nephropathy is significantly related to elevated dicarbonyl stress and possibly related to oxidative stress in three separate populations, suggesting that these factors play a role in determining individual susceptibility.
 ...
PMID:Susceptibility to diabetic nephropathy is related to dicarbonyl and oxidative stress. 1624 55

1. Increased oxidative stress has an important role in the pathogenesis of diabetic nephropathy. The aim of the present study was to evaluate diabetic nephropathy by determining markers of oxidative stress and the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), albumin and to investigate the possible protective effects of in vivo melatonin on renal tubular oxidative damage in diabetic rats. 2. Twenty-six rats were randomly divided into three groups: (i) group I, control, non-diabetic rats (n = 9); (ii) group II, untreated diabetic rats (n = 8); and (iii) group III, melatonin-treated diabetic rats (n = 9). In groups II and III, diabetes developed 3 days after administration of a single dose of streptozotocin (35 mg/kg, i.p.). Thereafter, whereas the rats in group II received no treatment, rats in group III began to receive 10 mg/kg per day, i.p., melatonin for 8 weeks. Malondialdehyde (MDA), an index of lipid peroxidation, NAG and microalbumin in the urine, markers of renal tubular damage, were the parameters used for oxidative stress-induced renal injury. Superoxide dismutase (SOD), xanthine oxidase (XO) and glutathione peroxidase (GSH-Px) activities were determined to evaluate changes in the anti-oxidant status of kidney tissue. 3. In untreated diabetic rats, urinary NAG, albumin and renal MDA levels were markedly increased compared with control rats (P < 0.0001). However, these parameters were reduced in diabetic rats by melatonin treatment (P < 0.0001). Urinary excretion of NAG was positively correlated with the microalbuminuria and renal MDA levels (r = 0.8; P < 0.0001). The SOD and XO activities in the untreated diabetic group were found to be significantly higher than those of the control group (P < 0.0001). Superoxide dismutase and XO activities decreased in melatonin-treated rats compared with untreated diabetic rats (P < 0.002 and P < 0.023, respectively). However, the decrease did reach levels seen in control rats. There were no significant differences in GSH-Px activity between the three groups. 4. Therefore, on the basis of these data, we suggest that urinary NAG, albumin excretion, XO activity and MDA levels are more valuable parameters showing the degree of renal tubular injury than classical markers of oxidative stress, including SOD and GSH-Px, in diabetic rat kidneys. Melatonin has an ameliorating effect on oxidative stress-induced renal tubular damage via its anti-oxidant properties. Thus, it may be suggested that urinary NAG excretion and microalbuminuria may be important markers showing the degree of renal changes and the success of long-term treatment of renal impairment with melatonin.
 ...
PMID:Melatonin reduces urinary excretion of N-acetyl-beta-D-glucosaminidase, albumin and renal oxidative markers in diabetic rats. 1644 6

Although most cellular glutathione (GSH) is in the cytoplasm, a distinctly regulated pool is present in mitochondria. Inasmuch as GSH synthesis is primarily restricted to the cytoplasm, the mitochondrial pool must derive from transport of cytoplasmic GSH across the mitochondrial inner membrane. Early studies in liver mitochondria primarily focused on the relationship between GSH status and membrane permeability and energetics. Because GSH is an anion at physiological pH, this suggested that some of the organic anion carriers present in the inner membrane could function in GSH transport. Indeed, studies by Lash and colleagues in isolated mitochondria from rat kidney showed that most of the transport (>80%) in that tissue could be accounted for by function of the dicarboxylate carrier (DIC, Slc25a10) and the oxoglutarate carrier (OGC, Slc25a11), which mediate electroneutral exchange of dicarboxylates for inorganic phosphate and 2-oxoglutarate for other dicarboxylates, respectively. The identity and function of specific carrier proteins in other tissues is less certain, although the OGC is expressed in heart, liver, and brain and the DIC is expressed in liver and kidney. An additional carrier that transports 2-oxoglutarate, the oxodicarboxylate or oxoadipate carrier (ODC; Slc25a21), has been described in rat and human liver and its expression has a wide tissue distribution, although its potential function in GSH transport has not been investigated. Overexpression of the cDNA for the DIC and OGC in a renal proximal tubule-derived cell line, NRK-52E cells, showed that enhanced carrier expression and activity protects against oxidative stress and chemically induced apoptosis. This has implications for development of novel therapeutic approaches for treatment of human diseases and pathological states. Several conditions, such as alcoholic liver disease, cirrhosis or other chronic biliary obstructive diseases, and diabetic nephropathy, are associated with depletion or oxidation of the mitochondrial GSH pool in liver or kidney.
 ...
PMID:Mitochondrial glutathione transport: physiological, pathological and toxicological implications. 1660 Jan 97

The therapeutic potential of lipoic acid (LA) in diabetes and diabetic nephropathy treatment was elucidated. Alloxan diabetic rabbits were treated daily for three weeks with either 10 or 50 mg of LA per kg body weight (i.p.). The following parameters were measured: 1) serum glucose, urea, creatinine and hydroxyl free radical (HFR) levels; 2) blood glutathione redox state; 3) urine albumin concentration; 4) hepatic and renal HFR levels, GSH/GSSG ratios, cysteine contents and the activities of the enzymes of glutathione metabolism; and 5) the activity of renal NADPH oxidase. Histological studies of kidneys were also performed. The treatment of diabetic rabbits with 50 mg of LA resulted in lethal hypoglycaemia in 50% of animals studied. Although the low dose of LA did not change serum glucose concentration, it decreased serum urea and creatinine concentrations, attenuated diabetes-induced decline in GSH/GSSG ratio and abolished hydroxyl free radicals accumulation in serum, liver and kidney cortex. LA did not change the activities of the enzymes of glutathione metabolism, but it elevated hepatic content of cysteine, which limits the rate of glutathione biosynthesis. Moreover, LA lowered urine albumin concentration and attenuated glomerulopathy characteristic of diabetes. However, it did not affect diabetes-stimulated activity of renal NADPH oxidase. In view of these data, it is concluded that low doses of LA might be useful for the therapy of diabetes and diabetic nephropathy. Beneficial action of LA seems to result mainly from direct scavenging of HFR and restoring glutathione redox state due to elevation of intracellular cysteine levels.
 ...
PMID:Lipoic acid ameliorates oxidative stress and renal injury in alloxan diabetic rabbits. 1815 51

The purpose of the present study was to investigate the effects of garlic (Allium sativum L.) on the diabetic nephropathy and oxidative stress induced by STZ (streptozotocin) in rats. Diabetes was induced in Male Sprague-Dawley rats by administering a single intraperitoneal injection of STZ (60 mg/kg of body weight). Administration of garlic, prepared as FGH (fresh garlic homogenate) significantly attenuated STZ-induced diabetic nephropathy as evaluated by assessment of serum glucose, insulin, total TAG (triacylglycerol), TC (total cholesterol) and Ccr (creatinine clearance) in control and STZ-induced diabetic rats. Urinary excretions of albumin and NAG (N-acetyl-beta-D-glucosaminidase) were also reduced following the treatment with FGH. In addition, significant inhibition of TBARSs (thiobarbituric acid-reacting substances) with a marked improvement of GSH content in the kidney homogenates was also observed. Moreover, renal tissue content and urinary excretion of nitrites were markedly decreased in this model, and virtually enhanced to the same levels as in the non-diabetic kidney following FGH supplementation. These data revealed that FGH has the ability to ameliorate STZ-induced diabetic nephropathy possibly through participation in the inhibition of oxidative damage to kidney and/or increased kidney nitric oxide bioavailability.
 ...
PMID:Renal oxidative stress and nitric oxide production in streptozotocin-induced diabetic nephropathy in rats: the possible modulatory effects of garlic (Allium sativum L.). 1858 10

Oxidative stress is a key cause in the development of diabetic nephropathy (DN). As a main receptor of oxidized low-density lipoprotein (oxLDL), LOX-1 plays an important role in the induction of leukocyte adhesion molecules, such as intercellular cell adhesion molecule-1 (ICAM-1). Taurine (TAU), a potent endogenous antioxidant, showed renoprotective effects in several model animals. This study was designed to determine the renoprotective effect and possible mechanism involved LOX-1 and ICAM-1 expression of taurine in early DN. Six-week-old male Wistar rats were divided into three groups: normal control (NC), diabetes mellitus (DM), and taurine-treated DM (DM+TAU). Diabetes was induced by streptozotocin (STZ, 60 mg/kg, i.p.). After the onset of diabetes, drinking water containing 1% taurine was given to rats in the DM+TAU group. After six weeks of treatment, blood glucose (BG), serum levels of creatinine (sCr) and BUN, and LOX-1 and ICAM-1 expression (protein and gene) in kidney cortices were estimated. Meanwhile, renal malondialdehyde (MDA) levels and glutathione peroxidase (GSH-Px) activities were examined as parameters of oxidative stress in diabetic rats. For DM+TAU rats, when compared with DM rats, the levels of serum BUN, sCr, and renal MDA were reduced, and the activities of renal GSH-Px were increased, but the BG levels were not influenced. Simultaneously, taurine attenuated histopathologic evidence of renal damages and reduced the overexpression of LOX-1 and ICAM-1 in kidney cortices of diabetic rats. In conclusion, taurine showed protective effects against early renal injury in diabetic rats. These renoprotective effects may be partly caused by suppression of oxLDL/LOX-1 system and subsequently ICAM-1 overexpression on renal cortex via its antioxidative property.
 ...
PMID:The protective effects of taurine against early renal injury in STZ-induced diabetic rats, correlated with inhibition of renal LOX-1-mediated ICAM-1 expression. 1879 49

The therapeutic potential of taurine was investigated under diabetic conditions. Alloxan diabetic rabbits were treated daily for three weeks with 1% taurine in drinking water. The following parameters were measured: 1) serum glucose, urea, creatinine and hydroxyl free radical (HFR) levels; 2) blood glutathione redox state; 3) urine albumin concentration; 4) hepatic and renal HFR levels, GSH/GSSG ratios and the activities of catalase, superoxide dismutase and the enzymes of glutathione metabolism; 5) renal NADPH oxidase activity; 6) the rates of renal and hepatic gluconeogenesis. Histological studies of kidneys were also performed. Taurine administration to diabetic rabbits resulted in 30% decrease in serum glucose level and the normalisation of diabetes-elevated rate of renal gluconeogenesis. It also decreased serum urea and creatinine concentrations, attenuated diabetes-evoked decline in GSH/GSSG ratio and abolished hydroxyl free radicals accumulation in serum, liver and kidney cortex. Animals treated with taurine exhibited elevated activities of hepatic gamma-glutamylcysteine syntetase and renal glutathione reductase and catalase. Moreover, taurine treatment evoked the normalisation of diabetes-stimulated activity of renal NADPH oxidase and attenuated both albuminuria and glomerulopathy characteristic of diabetes. In view of these data, it is concluded that: 1) diminished rate of renal gluconeogenesis seems to contribute to hypoglycaemic effect of taurine; 2) taurine-induced increase in the activities of catalase and the enzymes of glutathione metabolism is of importance for antioxidative action of this amino acid and 3) taurine nephroprotective properties might result from diminished renal NADPH oxidase activity. Thus, taurine seems to be beneficial for the therapy of both diabetes and diabetic nephropathy.
 ...
PMID:Hypoglycaemic, antioxidative and nephroprotective effects of taurine in alloxan diabetic rabbits. 1895 17


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>