A diet high in fructose (HFr) induces insulin resistance in animals. Free radicals are involved in the pathogenesis of HFr-induced insulin resistance. Carnosine (CAR) is a dipeptide with antioxidant properties. We investigated the effect of CAR alone or in combination with α-tocopherol (CAR + TOC) on HFr-induced insulin-resistant rats. Rats fed with HFr containing 60% fructose received CAR (2 g/L in drinking water) with/without TOC (200 mg/kg, i.m. twice a week) for 8 weeks. Insulin resistance, serum lipids, inflammation markers, hepatic lipids, lipid peroxides, and glutathione (GSH) levels together with glutathione peroxidase (GSH-Px) and superoxide dismutase 1 (CuZnSOD; SOD1) activities and their protein expressions were measured. Hepatic histopathological examinations were performed. HFr was observed to cause insulin resistance, inflammation and hypertriglyceridemia, and increased triglyceride and lipid peroxide levels in the liver. GSH-Px activity and expression decreased, but GSH levels and SOD1 activity and expression did not alter in HFr rats. Hepatic marker enzyme activities in serum increased and marked macro- and microvesicular steatosis were seen in the liver. CAR treatment did not alter insulin resistance and hypertriglyceridemia, but it decreased steatosis and lipid peroxidation without any change in the antioxidant system of the liver. However, CAR + TOC treatment decreased insulin resistance, inflammation, hepatic steatosis, and lipid peroxidation and increased GSH-Px activity and expression in the liver. Our results may indicate that CAR + TOC treatment is more effective to decrease HFr-induced insulin resistance, inflammation, hepatic steatosis, and dysfunction and pro-oxidant status in rats than CAR alone.

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The etiopathogenesis of thyroid cancer has not been clearly elucidated although the role of chronical inflammation and the imbalance between pro- and anti-inflammatory cytokines may play a role in the etiology. The aim of the present study was to investigate whether cytokine gene polymorphisms are associated with papillary thyroid cancer (PTC), and to evaluate the relationship between genotypes and clinical/laboratory manifestation of PTC. Tumor necrosis factorα (TNFα) G-308A (rs 1800629), interleukin-6 (IL-6) G-174C (rs 1800795) and IL-10 A-1082G (rs 1800896) single nucleotide polymorphisms in DNA from peripheral blood leukocytes of 190 patients with thyroid cancer and 216 healthy controls were investigated by real-time PCR combined with melting curve analysis. There was no notable risk for PTC afflicted by TNFα-308 and IL-6-174 alone. However, IL-10-1082 G allele frequency were higher among PTC patients than healthy controls (p=0.009). The patients with IL-10-1082 GG geotype have twofold increased risk of developing thyroid cancer according to AA genotype (OR 2.07, 95% CI 1.21-3.55). In addition, the concomitant presence of IL-10-1082 G allele (GG+AG genotypes) together with IL-6 -174 GG genotype has a nearly twofold increased risk for thyroid cancer (OR 1.75 with 95% CI 1.00-3.05, p=0.049). We suggest that IL-10-1082 G allele is associated with an increased risk of PTC. The polymorphism of IL-10 gene can improve our knowledge about the pathogenesis of PTC, and could provide to estimate people at the increased risk for PTC.

Objective: Oxidative stress plays an important role in doxorubicin (DOX)-induced toxicity. Carnosine (CAR) is a dipeptide with antioxidant properties. The aim of this study was to evaluate the decreasing or preventive effect of CAR alone or combination with vitamin E (CAR + Vit E) on DOX-induced toxicity in heart, liver, and brain of rats. Methods: Rats were treated with CAR (250 mg kg−1 day−1; intraperitoneally (i.p.)) or CAR + Vit E (equals 200 mg kg−1 α-tocopherol; once every 3 days; intramuscularly) for 12 consecutive days. On the 8th day of treatment, rats were injected with a single dose of DOX (30 mg kg−1, i.p.). Serum cardiac troponin I (cTnI), urea, and creatinine levels; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities; and oxidative stress parameters in tissues were measured. We also determined thiobarbituric acid reactive substances, diene conjugate, protein carbonyl (PC), and glutathione levels and antioxidant enzyme activities. Results: DOX resulted in increased serum cTnI, ALT, AST, urea, and creatinine levels and increased lipid peroxide and PC levels in tissues. CAR or CAR + Vit E treatments led to decreases in serum cTnI levels and ALT and AST activities. These treatments reduced prooxidant status and ameloriated histopathologic findings in the examined tissues. Conclusion: Our results may indicate that CAR alone, especially in combination with Vit E, protect against DOX-induced toxicity in heart, liver, and kidney tissues of rats. This was evidenced by improved cardiac, hepatic, and renal markers and restoration of the prooxidant state and amelioration of histopathologic changes.

Although there was no difference between survivors and non-survivors regarding the studied endocrine parameters, there were associations between cortisol, ACTH, IL-6 and IGFBP-3 and risk assessment scores, and, given that these scores correlated with mortality, these parameters might be useful as prognostic factors.