Correction: Topical Application of Ochratoxin A Causes DNA Damage and Tumor Initiation in Mouse Skin

tBHQ Induces a Hormetic Response That Protects L6 Myoblasts against the Toxic Effect of Palmitate

Nutritional status, in particular overweight and obesity, as well as sedentarism and high-fat diet consumption, are important risk factors to develop chronic diseases, which have a higher impact on the elderly's health. Therefore, these nutritional problems have become a concern to human healthspan and longevity. The fatty acids obtained thru the diet or due to fatty acid synthesis during obesity accumulate within the body generating toxicity and cell death. Fat is not only stored in adipose tissue, but it can also be stored in skeletal muscle. Palmitic acid (PA) has been reported as one of the most important saturated free fatty acids; it is associated to chronic oxidative stress and increased mitochondrial ROS production causing cell death by apoptosis. In skeletal muscle, palmitate has been associated with various pathophysiological consequences, which lead to muscle deterioration during aging and obesity. Since molecules that modify redox state have been proven to prevent cellular damage by inducing a hormetic response, the aim of this study was to evaluate if tert-butylhydroquinone (tBHQ) could activate an antioxidant hormetic response that would be able to protect L6 myoblasts from palmitate toxic effect. Our results provide evidence that tBHQ is able to protect L6 myoblasts against the toxicity induced by sodium palmitate due to a synergistic activation of different signaling pathways such as Nrf2 and NF-κB.

Selenium Yeast Alleviates Ochratoxin A-Induced Apoptosis and Oxidative Stress via Modulation of the PI3K/AKT and Nrf2/Keap1 Signaling Pathways in the Kidneys of Chickens

The purpose of this study was to investigate the protective effect and mechanism of yeast selenium (Se-Y) on ochratoxin- (OTA-) induced nephrotoxicity of chickens. A total of 80 one-day-old healthy chickens were randomly divided into 4 equal groups: control, OTA (50 μg/kg OTA), Se-Y (0.4 mg/kg Se-Y), and OTA+Se-Y (50 μg/kg OTA+0.4 mg/kg Se-Y). In the OTA chickens, differences in body weight, kidney coefficient, biochemical histological analysis, antioxidant capability, and the expression levels of the PI3K/AKT and Nrf2/Keap1 signaling pathway-related genes were observed. The levels of total superoxide dismutase (T-SOD), antioxidant capacity (T-AOC), catalase (CAT), and glutathione (T-GSH) significantly decreased, but the malondialdehyde (MDA) level of the kidneys significantly increased in the OTA treatment group. More importantly, treatment with Se-Y improved the antioxidant enzyme activities within the kidneys of chickens exposed to OTA. In addition, administration of OTA resulted in apoptosis and was associated with decreased expression of AKT, PI3K, and Bcl-2, which in turn enhanced expression of Caspase3, Bax, and P53. However, Se-Y improved the antioxidant defense system through activation of the Nrf2/Keap1 signaling pathway. Gene expression of Nrf2 and its target genes (HO-1, GSH-px, GLRX2, MnSOD, and CAT) was downregulated following OTA exposure. Conversely, Se-Y treatment resulted in a significant upregulation of the same genes. Besides, significant downregulations of protein expression of HO-1, CAT, MnSOD, Nrf2, and Bcl-2 and a significant upregulation of Caspase3 and Bax levels were observed after contaminated with OTA. Notably, OTA-induced apoptosis and oxidative damage in the kidney of chickens were reverted back to normal level in the OTA+Se-Y group. Taken together, the data suggest that Se-Y alleviates OTA-induced nephrotoxicity in chickens, possibly through the activation of the PI3K/AKT and Nrf2/Keap1 signaling pathways.