Cupuaçu extract protects the kidneys of diabetic rats by modulating Nrf2/NF-κB p65 and iNOS.

Diabetes is characterized by increased levels of oxidative stress. Its suggested that extract of cupuaçu could improve the antioxidant system in diabetes. The aim was to evaluate the effect of EC on Nrf2/NF-κB p65 in normal and diabetic rats. Male, adult Wistar rats (9-week-old) were distributed in 4 groups: control (CTL) and diabetic (DM) who received water; CTLEC and DMEC who received 1 mL/day of EC (1 g/mL), via gavage for 8 consecutive weeks. The diabetes was inducted with a single intravenous dose of 45 mg/kg streptozotocin. Glycemia and body weight were measured at the beginning and end of the protocol, and the renal tissue was analyzed by Western blot for SOD-1, SOD-2, CAT, GSSG, Nrf2, NF-κB p65, iNOS and 3-NT. Glycemia was reduced in DMEC vs. DM after 8 weeks of EC treatment. There was no difference in body weight of DMEC vs. DM; however, DMEC vs. DM presented increased levels of CAT and Nrf2, with a significant reduction of NF-κB p65, iNOS and 3-NT. Therefore, we suggest that EC could be utilized as a complementary therapy to ameliorate the antioxidant profile via Nrf2 and to delay the evolution of diabetic complications in renal tissue by inflammatory pathway inhibition.

Effect of Preloading With High Dose of Rosuvastatin on Serum Levels of Inflammatory Markers After Percutaneous Coronary Intervention.

OBJECTIVES: We sought to assess the effects of a high loading dose of rosuvastatin (40 mg) on acute inflammatory response after coronary stenting. METHODS: Patients with stable coronary disease without statin use (≥7 days) and undergoing elective percutaneous coronary intervention (PCI) in a native coronary artery were randomized to receive a loading dose of rosuvastatin (n = 64) or not (n = 61). Blood samples were obtained before statin intake (time point A), 3 hours after medication (time point B), and 3 hours after PCI (time point C). The primary goal was the comparison in the variation of the serum inflammatory markers and their gene expression at the different time points between the two groups. RESULTS: Baseline clinical, angiographic, and procedural characteristics did not significantly differ between the groups, except for the more frequent use of postdilation in the control group (73.4% vs 90.2%; P=.02). Patients pretreated with statin showed a reduction in the serum levels of interleukin (IL)-1ß (Δ = -0.491 pg/mL; Pinteraction<.001), IL-6 (Δ = -0.209 pg/mL; Pinteraction<.001), and plasminogen activator inhibitor 1 (Δ = -1.573 pg/mL; Pinteraction<.001) as well as in their genetic expression, which was not observed in the control group. Regarding high-sensitivity c-reactive protein, there was no significant variation in its value from time point A to C in patients pretreated with statin (P=.58) while it significantly increased in the control group (P=.04). CONCLUSIONS: Among patients with stable coronary artery disease undergoing PCI with stents, pretreatment with high dose of rosuvastatin resulted in significant reduction in the serum levels of important inflammatory markers and their genetic expression.

Cupuaçu extract reduces nitrosative stress and modulates inflammatory mediators in the kidneys of experimental diabetes.

BACKGROUND & AIMS: We have previously reported an increased nitrosative stress in the kidneys of diabetic animals, which was reduced by an antioxidant probiotic. The present study evaluated whether the extract of cupuaçu (EC), an antioxidant compound rich in polyphenols and theograndins, when administered at a dose that can be reasonably obtained through daily consumption, could delay the onset of diabetic complications in the kidney. METHODS: Mouse immortalized mesangial cells (MiMC) were placed in medium normal glucose (NG) or high glucose (HG), with or without EC (500, 100, 50 or 10 µg/mL) during 24, 48 or 72 h for analysis of viability, proliferation, nitric oxide (NO) levels and reactive oxygen species or nitrogen (ROS/RNS). Male, adult Wistar rats were distributed in 4 groups: control (CTL) and diabetic (DM) who received water; CTLEC and DMEC who received 1 mL/day of EC (1 g/mL), via gavage for 8 consecutive weeks. After, metabolic profile and renal function were evaluated and, kidneys were collected for analysis of NO, ROS, 3-nitrotyrosine (3-NT), endothelial nitric oxide synthase (eNOS), IL-6, IL-10, TNF-α and NF-κB p65. RESULTS: The MiMC showed normal viability in all groups, demonstrating that EC had no cytotoxic effect at doses on 24, 48 or 72 h. MiMC under HG presented significant increase in proliferation, NO and ROS vs. NG; these parameters were significantly reduced after 72 h of EC treatment (P < 0.05). DMEC showed a significant reduction of feed intake, ROS and NO, 3-NT, IL-6 and eNOS vs. DM (P < 0.05). Supplementation with EC at a dose consumed daily could improve control of nitrosative stress, combined with reduction of inflammatory factors, suggesting the importance of bioactive compounds as non-pharmacological adjuvant therapy to delay kidney complications in diabetic patients.

N-acetylcysteine protects against diabetic nephropathy through control of oxidative and nitrosative stress by recovery of nitric oxide in rats.

The diabetes mellitus (DM) induces several changes, with substantial increase of reactive oxygen species (ROS). The ROS cause damage to systemic and renal microvasculature, which could be one of the mechanisms involved in the development of diabetic nephropathy (DN). The ROS modulate other substances like the nitric oxide (NO), a vasodilator with important role in the renal function. N-acetylcysteine (NAC) is an antioxidant that acts replenishing intracellular cysteine levels, which is essential for glutathione formation. The aim of this study was to evaluate the effect of early or late NAC treatment on oxidative/nitrosative stress in DN progression. All rats were submitted to unilateral nephrectomy and diabetes was induced with streptozotocin. The animals were allocated into six groups: controls that received water (CTL) or NAC (CTL + NAC); diabetic groups that received early or late, water (DM-E; DM-L) or NAC (DM + NAC-E; DM + NAC-L), started on 5th day (early) or 4th week (late) after diabetes induction, during 8 weeks. After NAC treatment, the rats were placed in individual metabolic cages to obtain urine and blood samples for analysis of metabolic profile, renal function, thiobarbituric acid reactive substances (TBARS) and NO. At the end of the protocol, the renal cortex was removed for TBARS, NOS evaluation, antioxidants markers and histology. The DM-E group compared to CTL showed a significant increase in glycemia and proteinuria and impaired renal function; there was a significant increase of TBARS in plasma, urine and renal tissue, and also a significant decrease in plasma NO, which were reverted after early NAC treatment. The eNOS was decreased and iNOS was increased in DM-E vs. CTL, p < 0.05. The early NAC treatment in DM rats reduced proteinuria, creatinine, urea, TBARS and iNOS and, increased creatinine clearance, NO and eNOS, increasing significantly the antioxidant defenses, promoting elevated catalase and glutathione compared to DM-E group, all p < 0.05. The late NAC treatment in diabetic rats vs.DM-E showed reduced proteinuria and TBARS excretion and higher values of creatinine clearance and NO, all statistically significant. Histological analysis of the animals in DM-E or DM-L showed significant tubular changes with degeneration and vacuolization in tubular cells, dilated tubular lumen, intense glycosidic degeneration, and discreet mesangial expansion with interstitial fibrosis area. The DM + NAC-E group showed moderate glycosidic degeneration, however, did not present tubular degeneration or fibrosis. The DM + NAC-L group showed severe glycosidic degeneration, moderate tubular cell degeneration, light and focal dilatation of the tubules, with no fibrosis. Our study showed that NAC protected the diabetic rats against renal injury, probably due to the control of oxidative stress via recovery of the NO bioavailability, showing that early NAC was more effective than late treatment. All these data suggest that NAC may be useful in the adjuvant treatment in a safe way, in the early phase of the disease. Eventually, prolonged treatment, even if it is started later, could change the natural history of the disease, delaying the complications of diabetes in renal tissue.

P2X(7) receptor in the kidneys of diabetic rats submitted to aerobic training or to N-acetylcysteine supplementation [corrected].

Previous studies in our laboratory showed that N-acetylcysteine supplementation or aerobic training reduced oxidative stress and the progression of diabetic nephropathy in rats. The P2X(7 receptor is up-regulated in pathological conditions, such as diabetes mellitus. This up-regulation is related to oxidative stress and induces tissue apoptosis or necrosis. The aim of the present study is to assess the role of P2X(7) receptor in the kidneys of diabetic rats submitted to aerobic training or N-acetylcysteine supplementation. Diabetes was induced in male Wistar rats by streptozotocin (60 mg/kg, i.v.) and the training was done on a treadmill; N-acetylcysteine was given in the drinking water (600 mg/L). By confocal microscopy, as compared to control, the kidneys of diabetic rats showed increased P2 × 7 receptor expression and a higher activation in response to 2'(3')-O-(4-benzoylbenzoyl) adenosine5'-triphosphate (specific agonist) and adenosine triphosphate (nonspecific agonist) (all p<0.05). All these alterations were reduced in diabetic rats treated with N-acetylcysteine, exercise or both. We also observed measured proteinuria and albuminuria (early marker of diabetic nephropathy) in DM groups. Lipoperoxidation was strongly correlated with P2X(7) receptor expression, which was also correlated to NO•, thus associating this receptor to oxidative stress and kidney lesion. We suggest that P2X(7) receptor inhibition associated with the maintenance of redox homeostasis could be useful as coadjuvant treatment to delay the progression of diabetic nephropathy.

Electroacupuncture and moxibustion decrease renal sympathetic nerve activity and retard progression of renal disease in rats.

BACKGROUND/AIM: Chronic kidney disease (CKD) is an increasing major public health problem worldwide. The sympathetic nervous system and nitric oxide play an important role in the pathogenesis of CKD. Traditional Chinese medicine has accumulated thousands of years of therapeutic experiences. Electroacupuncture (EA) and moxibustion (MO) are two such therapeutic strategies. The aim of this study was to investigate the renal and hemodynamic effects of EA-MO in an experimental model of a CKD. METHODS: Male Wistar rats submitted to 5/6th nephrectomy (5/6 NX) were studied for 8 weeks. There were four groups: (1) control, normal rats; (2) NX, 5/6 NX only; (3) NX-AS, 5/6 NX and EA-MO session using sham points, and (4) NX-AM, 5/6 NX and EA-MO session using real acupoints. Biochemical and blood pressure studies, renal sympathetic nerve activity measurements, nitric oxide levels and the histopathological indices were assessed. RESULTS: The EA- and MO-treated group presented significant improvement in all measured functional and histopathological parameters. CONCLUSION: These findings suggest that EA-MO had beneficial effects on CKD. This effect was probably achieved by the modulation of the renal sympathetic nerve activity and nitric oxide levels, leading to decreased blood pressure, which is associated with less proteinuria.