Oat Protects against Diabetic Nephropathy in Rats via Attenuating Advanced Glycation End Products and Nuclear Factor Kappa B

Abstract

Oat, a rich source of soluble fiber, was considered to have a possible preventive effect on the progression of diabetic nephropathy. The present study aimed to assess this preventive activity in a rat model of diabetic nephropathy. Adult Wister rats were injected by streptozotocin (65 mg/kg). Animals were fed with normal diet or with a diet containing 20% oat (W/W) for 21 weeks. At the end of 21 weeks, all the kidney tissues were collected for various examinations. Our results suggested that oat could decrease the Scr and glucose level in blood of diabetic rats significantly (P < 0.05), and increase the creatinine clearance (P < 0.01). In histopathological examination, oat-fed rats showed a significant decrease in glomerulus segmented sclerosis and incidence of tubule vacuolar degeneration. By ELISA, we reported that oat feeding resulted in decreasing the levels of IL-6 and AGE in serum and kidney homogenate. In addition, the levels of oxidative stress markers were markedly improved as a result of oat feeding. Furthermore, using EMSA, we showed that oat attenuated the activation of NF-κB. Using RT-PCR, we found that oat could downregulate the TGF-β1 and RAGE expression at mRNA levels. This study suggests that oat can suppress diabetic nephropathy in rats effectively and may slow down the renal fibrosis by the disruption of the detrimental AGE-RAGE-NFκB axis.

Natural antioxidants in the treatment and prevention of diabetic nephropathy; a potential approach that warrants clinical trials

“…Oats are a source of several natural antioxidants [260]. Oat downregulates the TGF-β1 and receptors for AGE expression at mRNA levels and it can suppress DN in rats and may slow down renal fibrosis by the disruption of the detrimental receptors for AGE-NFκB axis [261]. After 12 weeks of diabetes in rats, oat treatment reduced BGL, HbA1c, and OS markers, and normalized NFκB activation and TNF-α expression.…”

Advanced glycation end product accumulation

“…Although primitive, increasing dietary fiber content attenuates the increase in AGEs and slows the progression of CKD. For instance, consumption of a high-fiber diet, such as oats, in rats slowed the progression of diabetic nephropathy with a concurrent reduction in RAGE and NF-κB levels [51]. Sevelamer carbonate, a nonabsorbed phosphate-binding polymer, is frequently used in CKD patients to decrease serum phosphate levels [52,53].…”

Ameliorative and Antioxidative Potential of Lactobacillus plantarum-Fermented Oat (Avena sativa) and Fermented Oat Supplemented with Sidr Honey against Streptozotocin-Induced Type 2 Diabetes in Rats

“…In hyperglycemia, various mechanisms generate free radicals, leading to the oxidation of lipids, proteins, and DNA, resulting in a significant state of oxidative stress [ 69 ]. The increase in free radicals reduces the production of biological antioxidative enzymes such as CAT, SOD, and GSH [ 70 ], making the tissues more vulnerable to oxidative stress [ 71 ]. The intervention of all fermented oat extracts in the present study recovered the altered activity of antioxidant enzymes in diabetic rats.…”

“…Consistently, we found that HFOE2 was more effective than the other subjected extracts and even more effective than Metformin treatment at preventing oxidative stress. These effects are strongly related to a decrease in lipid peroxidation [ 71 ], which could be attributed to the combination of the antioxidant activities of oats, honey, and L. plantarum metabolites [ 58 , 66 , 71 ]. Therefore, our results support the hypothesis that a good-quality cereal-based symbiotic product possesses potent antidiabetic activities with antioxidative stress potential.…”