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Context:Allium sativum L. (Liliaceae) (garlic) is a medicinal plant that is widely used in herbal medicine. Nephropathy is a complication of diabetes that is induced by long-term hyperglycaemia.Objective: The effects of aqueous extract of garlic (AGE) on the expression of tumour necrosis factor-alpha (TNF-α) and oxidative stress status were studied in the kidneys of rats with streptozotocin (STZ) + nicotinamide-induced diabetes.Materials and methods: Twenty-four Wistar rats were divided into four groups: control rats, rats with STZ + nicotinamide-induced diabetes that received a single dose of STZ (65 mg/kg) and nicotinamide (110 mg/kg) intraperitoneally, diabetic rats that were treated with garlic (2 g/kg/d, gavage), and normal rats that received garlic (2 g/kg/d, gavage). The glucose level was determined in the start of study, 7 d after induction of diabetes and 33 d after treatment with garlic. At the end of the treatment period, urea, uric acid and creatinine levels were estimated in sera. Malondialdehyde (MDA), total oxidant status (TOS), nitric oxide (NO) levels and TNF-α gene and protein expression were measured in the renal tissues of the rats.Results: The glucose, uric acid, and urea levels increased in the serum of diabetic rats compared with control rats, and decreased in garlic-treated diabetic rats compared with diabetic rats (p < 0.05). MDA, TOS and NO increased (p < 0.001) in diabetic rats compared with the control group, and decreased in garlic-treated diabetic rats compared with diabetic rats (p < 0.01). The level of TNF-α mRNA did not differ between groups but the TNF-α protein level in diabetic rats was higher than in the control rats (p < 0.01), whereas after treatment with garlic, it was close to the normal level (p < 0.01).Discussion and conclusion: These results indicate that garlic extract has hypoglycaemic, antioxidant and anti-inflammatory properties; therefore, it can be useful for the alleviation of diabetic complications.

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This paper describes the production, purification, and immobilization of l-asparaginase II (ASNase II) in chitosan nanoparticles (CSNPs). ASNase II is an effective antineoplastic agent, used in the acute lymphoblastic leukemia chemotherapy. Cloned ASNase II gene (ansB) in pAED4 plasmid was transformed into Escherichia coli BL21pLysS (DE3) competent cells and expressed under optimal conditions. The lyophilized enzyme was loaded into CSNPs by ionotropic gelation method. In order to get optimal entrapment efficiency, CSNP preparation, chitosan/tripolyphosphate (CS/TPP) ratio, and protein loading were investigated. ASNase II loading into CSNPs was confirmed by Fourier transform infrared (FTIR) spectroscopy, and morphological observation was carried out by transmission electron microscopy. Three absolute CS/TPP ratios were studied. Entrapment efficiency and loading capacity increased with increasing CS and TPP concentration. The best ratio was applied for obtaining optimal ASNase II-loaded CSNPs with the highest entrapment efficiency. Size, zeta potential, entrapment efficiency, and loading capacity of the optimal ASNase II-CSNPs were 340 ± 12 nm, 21.2 ± 3 mV, 76.2% and 47.6%, respectively. The immobilized enzyme showed an increased in vitro half-life in comparison with the free enzyme. The pH and thermostability of the immobilized enzyme was comparable with the free enzyme. This study leads to a better understanding of how to prepare CSNPs, how to achieve high encapsulation efficiency for a high molecular weight protein, and how to prolong the release of protein from CSNPs. A conceptual understanding of biological responses to ASNase II-loaded CSNPs is needed for the development of novel methods of drug delivery.

One of the most important complications of diabetes is nephropathy. This study investigates the effects of aqueous garlic extract on inflammation and oxidative stress status in the kidneys of diabetic rats. Male rats were divided into four groups- control rats, diabetic rats, garlic extract-treated diabetic rats, garlic extract-treated normal rats. The glucose, urea, uric acid, and creatinine levels were measured in sera using colorimetric methods. To determine the oxidative stress condition in the kidney tissues, total antioxidant capacity (TAC), malondialdehyde (MDA), and total oxidant status (TOS) were measured using colorimetric methods. Inflammation status was evaluated by the determination of tumor necrosis factor-alpha (TNF-α) gene and protein expression using qRT-PCR and ELISA respectively, while nitric oxide (NO) level in these tissues was measured using the Griess method. Histological examination of Kidneys was carried out by H&E staining. The levels of glucose, urea, and uric acid were found to increase in the serum of diabetic rats and decrease in that of diabetic rats after treatment with garlic. Measurement of MDA, TOS, and TAC revealed oxidative stress in diabetic rats, which improved after receiving the extract. The NO and TNF-α protein levels in diabetic rats were higher than those in control rats. After treatment with garlic, the levels of TNF-α protein and NO became close to the normal levels. Histological results confirmed certain other data as well. Garlic has antioxidant properties; therefore, it can reduce oxidative stress, which plays an important role in the development of diabetic nephropathy. Reduction in oxidative stress has beneficial effects on inflammation because it leads to a decrease in the level of TNF-α.