The high morbidity of metabolic dysfunction diseases has heightened interest in seeking natural and safe compounds to maintain optimal health. γ-Oryzanol (OZ), the ferulic acid (FA) ester with phytosterols, mainly present in rice bran has been shown to improve markers of metabolic syndrome. This study investigates the effects of FA and OZ on alleviating high-fat and high-fructose diet (HFFD)-induced metabolic syndrome parameters. Male SD rats were fed with a regular rodent diet, HFFD, or HFFD supplemented with 0.05% FA or 0.16% OZ (equimolar concentrations) for 13 weeks. Food intake, organ indices, serum lipid profiles, glucose metabolism, insulin resistance (IR) index and cytokine levels were analyzed. The mechanisms were further investigated in oleic acid-stimulated HepG2 cells by analyzing triglyceride (TG) content and lipogenesis-related gene expressions. In the in vivo study, FA and OZ exhibited similar effects in alleviating HFFD-induced obesity, hyperlipidemia, hyperglycemia, and IR. However, only OZ treatment significantly decreased liver index and hepatic TG content, lowered serum levels of C-reactive protein and IL-6, and increased serum concentration of adiponectin. In the in vitro assay, only OZ administration significantly inhibited intracellular TG accumulation and down-regulated expression of stearoyl coenzyme-A desaturase-1, which might facilitate OZ to enhance its hepatoprotective effect. OZ is more effective than FA in inhibiting hepatic fat accumulation and inflammation. Thus, FA and OZ could be used as dietary supplements to alleviate the deleterious effects of HFFD.
19 September 2016 in Journal of Agricultural and Food Chemistry
Alcoholic liver disease (ALD) has become one of the major global health problems, with augmented morbidity and mortality. Evidence indicates that flavonoids can reduce the risk of ALD owing to their biological properties. However, the effect of structurally different flavonoid subclasses on alleviating alcohol-induced liver damage in a same model has never been studied. In this study, mice were supplemented with five kinds of flavonoid subgroups, apigenin (flavone), quercetin (flavonol), naringenin (flavanone), (-)-epigallocatechin gallate (flavanol), and genistein (isoflavone), in the same dose (0.3 mmol kg−1 body weight) and then given 50% alcohol by gastric perfusion for five consecutive weeks. The results demonstrated that genistein and naringenin had greater benefits in terms of mitigating fibrosis and apoptosis, respectively, in the liver. Lipid deposition, partial inflammatory-related factors (nuclear factor kappa B p65, cyclooxygenase-2, and interleukin-6 levels), and hepatic histopathological alterations were similarly attenuated by five kinds of flavonoids. All the flavonoids also showed different degrees of influence on protecting against alcoholic liver injury on other aspects, such as serum biochemistry makers, hepatic lipid accumulation, lipid peroxidation, antioxidant capacities, and inflammation.
Excessive visible light exposure can induce damage to retinal cells and contribute to the development or progression of age-related macular degeneration. In this study we created a model of phototoxicity in pigmented rabbits. Furthermore, we investigated the protective effect of bilberry anthocyanin extract (BAE, Table A1) and explored the possible mechanisms of action in this model. The model of light-induced retinal damage was established by the pigmented rabbits exposed to light at 18,000 lx for 2 h, and they were sacrificed on day 7. After administration of BAE at dosages of 250 and 500 mg/kg/day, retinal dysfunction was significantly inhibited in terms of electroretinograms, and the decreased thicknesses of retinal outer nuclear layer and lengths of the outer segments of the photoreceptor cells were suppressed in rabbits with retinal degeneration. BAE attenuated the changes caused by light to certain apoptotic proteins (Bax, Bcl-2, and caspase-3). The extract increased the levels of superoxide dismutase, glutathione peroxidase, and catalase, as well as the total antioxidant capacity, but decreased the malondialdehyde level in the retinal cells. BAE inhibited the light-induced elevation in the levels of proinflammatory cytokines and angiogenic parameters (IL-1β and VEGF). Results showed that visible light-induced retinal degeneration model in pigmented rabbits was successfully established and BAE exhibited protective effects by increasing the antioxidant defense mechanisms, suppressing lipid peroxidation and proinflammatory cytokines, and inhibiting retinal cells apoptosis.