Phenolic-rich smoothie consumption ameliorates non-alcoholic fatty liver disease in obesity mice by increasing antioxidant response

Strawberry, Blueberry, and Strawberry-Blueberry Blend Beverages Prevent Hepatic Steatosis in Obese Rats by Modulating Key Genes Involved in Lipid Metabolism

There is an increasing interest in developing natural herb-infused functional beverages with health benefits; therefore, in this study, we aimed to evaluate the effect of strawberry, blueberry, and strawberry-blueberry blend decoction-based functional beverages on obesity-related metabolic alterations in high-fat and high-fructose diet-fed rats. The administration of the three berry-based beverages for eighteen weeks prevented the development of hypertriglyceridemia in obese rats (1.29-1.78-fold) and hepatic triglyceride accumulation (1.38-1.61-fold), preventing the development of hepatic steatosis. Furthermore, all beverages significantly down-regulated Fasn hepatic expression, whereas the strawberry beverage showed the greatest down-regulation of Acaca, involved in fatty acid de novo synthesis. Moreover, the strawberry beverage showed the most significant up-regulation of hepatic Cpt1 and Acadm (fatty acid β-oxidation). In contrast, the blueberry beverage showed the most significant down-regulation of hepatic Fatp5 and Cd36 (fatty acid intracellular transport). Nevertheless, no beneficial effect was observed on biometric measurements, adipose tissue composition, and insulin resistance. On the other hand, several urolithins and their derivatives, and other urinary polyphenol metabolites were identified after the strawberry-based beverages supplementation. In contrast, enterolactone was found significantly increase after the intake of blueberry-based beverages. These results demonstrate that functional beverages elaborated with berry fruits prevent diet-induced hypertriglyceridemia and hepatic steatosis by modulating critical genes involved in fatty acid hepatic metabolism.

Rosmarinic acid exerts anti-inflammatory effect and relieves oxidative stress via Nrf2 activation in carbon tetrachloride-induced liver damage

Background

Rosmarinic acid (RA) has biological and pharmaceutical properties and shows hepatoprotective potential. However, the hepatoprotective mechanism of RA needs to be further elucidated in vivo and in vitro.

Objective

This study was aimed to evaluate the protective effect of RA on carbon tetrachloride (CCl₄)-induced liver injury and elucidate the hepatoprotective mechanism of RA in vivo and in vitro.

Design

In vivo, the mice were orally administrated with RA (10, 20, and 40 mg/kg bw) daily for 28 consecutive days, and 1% CCl₄ (5 mL/kg bw, dissolved in peanut oil) was used to induce liver injury. In vitro, the big rat liver (BRL) hepatocytes were pretreated with RA (0.2, 0.4, and 0.8 mg/mL) for 3 h, and then the hepatocytes were treated with CC1₄ (final concentration, 14 mM) for 3 h to induce cell injury. The related indexes, including hepatic function, oxidative stress, protein expression of nuclear-factor erythroid 2-related factor 2 (Nrf2) pathway, inflammation, histopathological change, hepatocyte apoptosis, and mitochondrial membrane potential, were evaluated.

Results

Oral administration of RA to mice considerably decreased the CCl₄-induced elevation of serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), triacylglycerols (TG), total cholesterol (TC), total bilirubin (TBIL), hepatic reactive oxygen species (ROS), malondialdehyde (MDA), nitric oxide (NO), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8). RA also increased the levels of hepatic glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) and the protein expressions of Nrf2, quinine oxidoreductase (NQO1), and heme oxygenease-1 (HO-1). Histopathological examinations indicated that RA (20 and 40 mg/kg bw) alleviated the liver tissue injury induced by CCl₄. Moreover, RA inhibited the hepatocyte apoptosis caused by CCl₄ based on TUNEL assay. In vitro, RA pretreatment remarkably recovered the cell viability and reduced the CCl₄-induced elevation of AST, ALT, lactate dehydrogenase (LDH), ROS, and 8-OHdG. Immunohistochemistry staining demonstrated that pretreatment with RA markedly inhibited the expression of IL-6, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and Caspase-3 in CCl₄-treated hepatocytes. Additionally, RA pretreatment significantly decreased the elevation of mitochondrial membrane potential in CCl₄-treated hepatocytes.

Conclusions

RA exerted a protective effect against CCl₄-induced liver injury in mice through activating Nrf2 signaling pathway, reducing antioxidant damage, suppressing inflammatory response, and inhibiting hepatocyte apoptosis. RA could attenuate BRL hepatocyte ROS production, DNA oxidative damage, inflammatory response, and apoptosis induced by CCl₄ exposure.

Açaí seed extract (ASE) rich in proanthocyanidins improves cardiovascular remodeling by increasing antioxidant response in obese high-fat diet-fed mice

Obesity is recognized as an independent risk factor for cardiovascular diseases and is an important contributor to cardiac mortality. Açaí seed extract (ASE), rich in proanthocyanidins, has been shown to have potential anti-obesity effects. This study aimed to investigate the therapeutic effect of ASE in cardiovascular remodeling associated with obesity and compare it with that of rosuvastatin. Male C57BL/6 mice were fed a high-fat diet or a standard diet for 12 weeks. The ASE (300 mg/kg/day) and rosuvastatin (20 mg/kg/day) treatments started in the 8th week until the 12th week, totaling 4 weeks of treatment. Our data showed that treatment with ASE and rosuvastatin reduced body weight, ameliorated lipid profile, and improved cardiovascular remodeling. Treatment with ASE but not rosuvastatin reduced hyperglycemia and oxidative stress by reducing immunostaining of 8-isoprostane and increasing SOD-1 and GPx expression in HFD mice. ASE and rosuvastatin reduced NOX4 expression, increased SIRT-1 and Nrf2 expression and catalase and GPx activities, and improved vascular and cardiac remodeling in HFD mice. The therapeutic effect of ASE was similar to that of rosuvastatin in reducing dyslipidemia and cardiovascular remodeling but was superior in reducing oxidative damage and hyperglycemia, suggesting that ASE was a promising natural product for the treatment of cardiovascular alterations associated with obesity.

Pineapple fruit improves vascular endothelial dysfunction, hepatic steatosis, and cholesterol metabolism in rats fed a high-cholesterol diet

Hypercholesterolaemia is a significant risk factor for developing vascular disease and fatty liver. Pineapple (Ananas comosus), a tropical fruit widely cultivated in Asia, is reported to exhibit antioxidant and cholesterol-lowering...

Flavonoids from Rosa davurica Pall. fruits prevent high-fat diet-induced obesity and liver injury via modulation of the gut microbiota in mice

Rosa davurica Pall. (RDP) fruits are popularly consumed as beverages and healthy food in China because of their various beneficial activities. In particular, flavonoids are one of the major active ingredients of RDP fruits with predominant pharmacological effects. However, the anti-obesity activities of flavonoids from RDP fruits and their regulation effect on the gut microbiota have not been determined. In the present study, the flavonoid-rich extracts (RDPF) were isolated from RDP fruits and their anti-obesity effects were investigated using a high-fat diet (HFD)-induced obese mouse model. The results showed that RDPF intervention significantly inhibited the body weight, liver weight, kidney weight and epididymal adipose tissue weight of HFD-fed mice without affecting the calorie intake. Plasma lipid levels were also significantly lowered by RDPF treatment. Histological examination showed that RDPF supplementation partially recovered HFD-induced hepatic steatosis in the liver. RDPF also prevented oxidative injury of the liver, as evidenced by the altered superoxide dismutase (SOD), catalase (CAT) and malondialdehyde (MDA) levels. The expression levels of CCAAT/enhancer binding protein α (C/EBPα), sterol regulatory element binding protein-1C (SREBP-1C), fatty acid synthase (FAS), acyl-coenzyme A oxidase 1 (ACOX1), peroxisome proliferator-activated receptor (PPARα) and CAT mRNA in the livers of mice were also regulated by RDPF administration. 16S rRNA gene sequence data further indicated that RDPF addition increased the microbial diversity and reshaped the community composition. Intriguingly, RDPF intervention did not exhibit inhibitory tendency toward the ratio of Firmicutes to Bacteroidetes, but markedly decreased the relative abundance of Erysipelotrichaceae. This study provided novel insights into the application of RDPF in the food industry.