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Simple Summary: ALDH2, mitochondrial aldehyde dehydrogenase 2, is a critical enzyme involved in ethanol clearance in acetaldehyde metabolism. The prevalence of the ALDH2*2 variant is 45% in the Taiwanese population. ALDH2 reportedly has protective properties on myocardial damage, stroke, and diabetic retina damage. However, the effects of ALDH2 in modulation of metabolic syndromes remain unclear. The study evaluated the roles of ALDH2 in a high-fat-diet-induced metabolic syndrome in mice. We explored the effects of ALDH2 gene on NAFLD and potential association with gut microbiota. Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a critical enzyme involved in ethanol clearance in acetaldehyde metabolism and plays a key role in protecting the liver. The ALDH2*2 mutation causes a significant decrease in acetaldehyde scavenging capacity, leading to the accumulation of acetaldehyde after consuming alcohol. The prevalence of the ALDH2*2 variant is in 45% of Taiwanese individuals. ALDH2 reportedly has protective properties on myocardial damage, stroke, and diabetic retina damage. However, the effects of ALDH2 in the modulation of metabolic syndromes remain unclear. This study evaluates the roles of ALDH2 in a high-fat-diet-induced metabolic syndrome in mice. Male (M) and female (F) wild-type (WT) and ALDH2 knock-in C57BL/6J mice (4–5 weeks old) were fed a high-fat diet for 16 weeks. Results showed that the body and white-adipose-tissue weights were significantly increased in ALDH2-M compared to those in the other groups. We observed markedly elevated serum levels of alanine transaminase and glucose. Oral glucose-tolerance test and homeostasis-model assessment of insulin resistance (HOMA-IR) values were significantly higher in ALDH2-M mice than those in WT-M mice, with no observable differences in female mice. Abundant steatosis and inflammatory cells were observed in ALDH2-M, with significantly decreased expression of hepatic genes IRS2, GLUT4, and PGC-1α compared to that in WT-M. ALDH2 gene mutation also affected the β-diversity of gut microbiota in ALDH2-M resulting in the decreased abundance of Actinobacteria and an increase in Deferribacteres. Our results suggest that potential changes in gut microbiota may be associated with the defective ALDH2 exacerbation of high-fat-diet-induced liver diseases in male mice. However, female mice were not affected, and sex hormones may be an important factor that requires further investigation. [ABSTRACT FROM AUTHOR]

High fructose diet causes metabolic syndrome and induces host gut microbial dysbiosis and related obesity and nonalcoholic fatty liver disease (NAFLD). Several antibiotic treatments could prevent fatty liver. However, there are studies that have demonstrated that a high-fructose diet could influence the gut microbial dysbiosis and induce fatty liver. The purpose of this study was performed to partially modify the gut bacterial composition with a single cefotaxime treatment, which might affect the fructose-induced NAFLD severity. The C57BL/6JNarl male mice were divided into four groups including vehicle/chow diet (VE-CD), vehicle/high-fructose diet (VE-FD), antibiotic (cefotaxime (CF))/CD, and CF/FD. The results showed that body weight gain, moderate hepatic steatosis severity, epididymal white adipose tissue hypertrophy, and insulin resistance occurrence with NAFLD-related symptoms were observed only in the CF-FD group. The raised protein expression of hepatic lipogenesis was observed in the CF-FD group, but lipolysis protein expression was no difference. The diversity and composition of microbiota were significantly reduced in the CF-FD group. The Erysipelatoclostridium, Enterobacteriaceae, Lachnospiraceae, and Escherichia Shigella were in increased abundance in the feces of CF-FD group compared with VE-FD group. The novel model reveals that particular antibiotics such as cefotaxime co-treatment with high-fructose diet may affect the gut microbiota accelerating the NAFLD and obesity. [ABSTRACT FROM AUTHOR]

Beef extract (BE) is a nutritional supplement obtained by cooking beef meat. Compared with traditional chicken essence or clam extract, BE is cheaper to produce and may be used for wound healing, as a chemotherapy supplement, or to prevent fatigue. In this study, we evaluated the potential beneficial effects of BE on exercise performance and the related role of the gut microbiota. Pathogen-free male BALB/c mice were divided into three groups to receive vehicle or BE (0, 12.3, or 24.6 mL/kg) by oral gavage for 28 days. Exercise performance was evaluated using forelimb grip strength, swimming time to exhaustion, and physiological levels of fatigue-related biomarkers (serum lactate, blood urea nitrogen, and glucose levels) after physical challenges. BE supplementation elevated endurance and grip strength in a dose-dependent manner; significantly decreased lactate and blood urea nitrogen levels after physical challenge; and significantly increased muscle glycogen content. The germ-free mice supplemented with BE or an equal-calorie portion of albumin did not show significant differences from the other groups in exercise performance and levels of related biomarkers. Therefore, BE supplementation improved endurance and reduced fatigue, which might be related to BE composition, but had no correlation with the gut microbiota. [ABSTRACT FROM AUTHOR]

The comprehensive studies done on resveratrol (RES) support that this polyphenol has multiple bioactivities and is widely accepted for dietary supplementation. Furthermore, regular exercise is known to have benefits on health and is considered as a form of preventive medicine. Although the vast majority of prior studies emphasize the efficacy of aerobic exercise in promoting physiological adaptions, other types of exercise, such as resistance exercise and high-intensity interval training (HIIT), may achieve similar or different physiological outcomes. Few studies have looked into the effectiveness of a combinational, synergistic approach to exercise using a weight-loading ladder climbing animal platform. In this study, ICR mice were allocated randomly to the RES and training groups using a two-way ANOVA (RES × Training) design. Exercise capacities, including grip strength, aerobic performance, and anaerobic performance, were assessed and the physiological adaptions were evaluated using fatigue-associated indexes that were implemented immediately after the exercise intervention. In addition, glycogen levels, muscular characteristics, and safety issues, including body composition, histopathology, and biochemistry, were further elucidated. Synergistic effects were observed on grip strength, anaerobic capacities, and exercise lactate, with significant interaction effects. Moreover, the training or RES may have contributed significantly to elevating aerobic capacity, tissue glycogen, and muscle hypertrophy. Toxic and other deleterious effects were also considered to evaluate the safety of the intervention. Resistance exercise in combination with resveratrol supplementation may be applied in the general population to achieve better physiological benefits, promote overall health, and promote participation in regular physical activities. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa exotoxin A (PEA) causes severe hepatotoxicity in experimental animals and is useful in investigations of immune-mediated liver injury. However, strain differences in the sensitivity to PEA-induced hepatotoxicity in rats remains be elucidated. In this study, we determined the severity of PEA-induced hepatotoxicity in six genetically different rat strains. Male LE (Long Evans), Wistar, F344, WKY, BN/SsN and LEW rats were administered a single intravenous injection of PEA (20 μg/kg). Significantly elevated serum ALT and AST levels, massive necrosis and hemorrhage, and numerous TUNEL-positive hepatocytes were observed in BN/SsN rats. In contrast, low levels of ALT and AST as well as mild changes in liver histopathology were observed in Wistar and F344 rats. Moderate levels of hepatic injuries were observed in LE, WKY, and LEW rats. Pro-inflammatory cytokines including TNF-α, IL-2 and IL-6 serum levels were markedly increased in BN/SsN rats compared to Wistar and F344 rats. However, the hepatic levels of low density lipoprotein receptor-related protein (LRP), which functions as the PEA receptor, were not significantly different in each strain. Taken together, we suggest that BN/SsN is the most sensitive rat strain, whereas Wistar and F344 were the most resistant rat strains to PEA-induced liver damage. The different genetic background of rat strains plays an important role in the susceptibility to PEA-induced epatotoxicity that may depend on immune-regulation but not LRP receptor levels., Competing Interests: The authors declare no conflict of interest.

Panax quinquefolium L. (American Ginseng, AG) is one of the most popular herbal medicines in the World. We aimed to investigate whether chronic (28-day) supplementation with AG could protect against ethanol-induced ulcer in gastric tissue. Furthermore, we investigated the possible molecular mechanisms leading to AG-mediated gastric mucosal protection. We randomized 32 male Wistar rats into four groups for treatment (n=8 per group): supplementation with water (vehicle) and low-dose (AG-1X), medium-dose (AG-2X) and high-dose (AG-5X) AG at 0, 250, 500, and 1250 mg/kg, respectively. In the first experiment, animals were fed vehicle or AG treatments for 4 weeks. At day 29, 75% ethanol was given orally to each animal at 10 mL/kg to induce gastric ulceration for 2 h. In a second experiment, animals were pretreated orally with each treatment for 1 hr before a single oral administration of ethanol (70%, 10 mL/kg). Trend analysis revealed that AG treatments inhibited ethanol-induced gastric mucosal damage. AG supplementation dose-dependently decreased the pro-inflammatory levels of interleukin 1β and cyclooxygenase 2 and the expression of pro-apoptotic proteins tBid, cytochrome C, and caspases-9 and -3 and increased the levels of anti-apoptotic proteins Bcl-2, Bcl-xL and p-Bad. AG could have pharmacological potential for treating gastric ulcer.