Hypoglycemic and Hypolipogenic Action of Acetic Acid and Monascus-Fermented Grain Vinegar: A Comparative Study.

Acetic acid has been proposed to improve lifestyle-related diseases, including hyperlipidemia and hyperglycemia. This study compared the hypoglycemic and hypolipogenic effects of acetic acid vinegar (AV, contains only 4% acetic acid) and Monascus-fermented grain vinegar (MV) containing various bioactive compounds in 3T3L1 cells and C57BL/KsJ-db/db mice (DB). The DB were divided randomly into three treatment groups containing nine mice each; DB-, AV-, and MV-groups were orally administered 1 mL/kg/day of distilled water, acetic acid vinegar, and Monascus vinegar, respectively, for 8 weeks. Exposure to AV and MV inhibited the adipogenic differentiation of 3T3L1 preadipocytes and lipid accumulation during differentiation. Oral administration of AV or MV to the mice resulted in a marked reduction in the body weight, liver weight, and hepatic triglyceride content compared to the control DB-group. Moreover, treatment with AV and MV clearly increased the expression of cyclic adenosine monophosphate (cAMP) and AMP-activated protein kinase (AMPK) and suppressed the expression of fatty acid synthetase in liver tissues of DB. Significantly, lower levels of fasting blood glucose, insulin, leptin, and the glycosylated hemoglobin (HbA1c) as well as higher levels of the skeletal muscle GLUT4 expression were obtained in the AV- or MV-groups than levels determined in the control DB-group (P < .05). Although MV has the potential to be a natural alternative treatment for obesity-associated type 2 diabetes, this study suggests that acetic acid is the central ingredient in MV responsible for the hypoglycemic and hypolipogenic effects in the DB mice.

Vitamin C alleviates alcoholic liver injury by suppressing neutrophil infiltration in senescence marker protein 30-knockout mice irrespective of its antioxidant effects.

AIMS: Alcoholic liver disease (ALD) comprises an important component in chronic liver diseases, and its clinical significance has increased due to the high consumption of alcohol worldwide. Vitamin C is a potent antioxidant, and several previous studies have suggested that its therapeutic role in ALD is derived from its antioxidant role. However, its anti-inflammatory role in ALD remains to be elucidated. Especially, the relationship between vitamin C and infiltration of neutrophils in ALD has not been discussed to date. For the reason, the present study investigated the precise role of vitamin C in neutrophil infiltration in ALD. MAIN METHODS: In the present study, wild-type C57BL/6 and vitamin C-deficient senescence marker protein 30-knockout mice were pair-fed with a Lieber-DeCarli control or ethanol diet. Ethanol-fed groups were fed with increasing concentrations of EtOH (Lieber-DeCarli control diet for 5 days, 3% EtOH diet for a week, and 5% diet for 2 weeks) with or without vitamin C supplementation. KEY FINDINGS: Vitamin C dramatically attenuated the ethanol-mediated liver disease in the vitamin C-deficient ethanol-fed mice group by suppressing the infiltration of neutrophils accompanied by less CD68-positive cell infiltration. This attenuating role of vitamin C in neutrophil infiltration in the liver is associated with its protective effect for the ethanol-mediated intestinal damage in vitamin C-deficient ethanol-fed mice. SIGNIFICANCE: This study provides a novel possibility of vitamin C to be used as an anti-inflammatory therapeutic agent associated with neutrophil infiltration in ALD, thereby helping to establish strategies for attenuating ALD.

Effects of losartan and l-serine in a mouse liver fibrosis model.

Hepatic fibrosis is a common liver disease caused by excessive collagen deposition in the liver. Since liver transplantation is the only current treatment for cirrhosis with worsened fibrosis, a new strategy to develop anti-fibrosis drugs with no adverse effects is necessary. In recent studies, amino acids have been applied as a type of therapy in various fields. l-serine plays a major role in antioxidant production via the maintenance of nicotinamide adenine dinucleotide phosphate hydride production in the mitochondria. l-serine may reduce fibrotic lesions in a mouse model of chronic liver injury. This study used 27 six-week-old C57BL/6 mice and injected them three times a week for eight weeks with carbon tetrachloride (CCl4) (1.5 mg/kg, 10% v/v CCl4 in olive oil) to create a hepatic fibrosis mouse model. The mice, which weighed approximately 20-30 g, were randomly classified into four groups: 1) the olive oil group, which received intraperitoneal injection of olive oil (1.5 mg/kg, 3 times per week for 8 weeks); 2) the CCl4-only group; 3) the CCl4 + losartan (10 mg/kg, PO, 5 days on, weekend off for 8 weeks) group; and 4) the CCl4 + l-serine (100 g/L, free access for 8 weeks) group. Hematoxylin and eosin staining and Masson's trichrome staining showed reduced inflammatory cell deposition and collagen deposition in the liver tissue in the l-serine supplemented group. l-serine was found to reduce the spread of hepatic fibrosis and has potential use in clinical settings. Based on these histopathological observations, l-serine is a potential anti-fibrosis drug.