To determine the polyphenol compounds (phenolic and flavonoid compounds), antioxidant activity [1,1-diphenylpicryl-2-picrylhydrazyl (DPPH) radical scavenging activity] and DNA damage inhibitory effect of fermented local red brown rice. DNA nicking assay was employed to determine the antioxidant activity of the fermented rice extract. Phytochemical screening was completed using standard methods and DPPH radical assays were used to confirm the antioxidant properties of the extracts. After four days of fermentation, fermented red brown rice had more polyphenol compounds compared to unfermented counterpart. Fermented red brown rice showed greater antioxidant properties with EC50 value of DPPH radical scavenging of 43.00 mg extract/mL or 8 mg quercetin equivalent antioxidant activity. In addition, fermented rice extract showed DNA damage inhibitory effect to a certain extent. It protected DNA from reactive oxygen species; however, at high concentration it might induce reductive damage to DNA, whereas, unfermented red brown rice showed weak DNA damage inhibitory effect. Fermented red brown rice could protect DNA from oxidative damage but might induce reductive damage to DNA at high concentrations.
In this study, we hypothesized that different strains of Lactobacillus can alleviate hyperlipidemia and liver steatosis via activation of 5′ adenosine monophosphate-activated protein kinase (AMPK), an enzyme that is involved in cellular energy homeostasis, in aged rats. Male rats were fed with a high-fat diet (HFD) and injected with D-galactose daily over 12 weeks to induce aging. Treatments included (n = 6) (i) normal diet (ND), (ii) HFD, (iii) HFD-statin (lovastatin 2 mg/kg/day), (iv) HFD-Lactobacillus fermentum DR9 (10 log CFU/day), (v) HFD-Lactobacillus plantarum DR7 (10 log CFU/day), and (vi) HFD-Lactobacillus reuteri 8513d (10 log CFU/day). Rats administered with statin, DR9, and 8513d reduced serum total cholesterol levels after eight weeks (p < 0.05), while the administration of DR7 reduced serum triglycerides level after 12 weeks (p < 0.05) as compared to the HFD control. A more prominent effect was observed from the administration of DR7, where positive effects were observed, ranging from hepatic gene expressions to liver histology as compared to the control (p < 0.05); downregulation of hepatic lipid synthesis and β-oxidation gene stearoyl-CoA desaturase 1 (SCD1), upregulation of hepatic sterol excretion genes of ATP-binding cassette subfamily G member 5 and 8 (ABCG5 and ABCG8), lesser degree of liver steatosis, and upregulation of hepatic energy metabolisms genes AMPKα1 and AMPKα2. Taken altogether, this study illustrated that the administration of selected Lactobacillus strains led to improved lipid profiles via activation of energy and lipid metabolisms, suggesting the potentials of Lactobacillus as a promising natural intervention for alleviation of cardiovascular and liver diseases.
Skin aging, which affects all living organisms, is associated with oxidative stress. Probiotics exhibit antioxidant properties by producing reactive metabolites that counter oxidative stress. We hypothesized that Limosilactobacillus fermentum USM 4189 (LF 4189) has antioxidative properties and may prevent skin aging. In the present study, we used a D-galactose senescence-induced rat model to evaluate the potential antioxidative capability of LF 4189. The results indicated that rats administered LF 4189 exhibited increased plasma antioxidative activity (P=0.004), lipid peroxidation capacity (P=0.007), and skin elasticity compared with untreated aged rats (P=0.005). LF 4189 prevented telomere length shortening (P<0.05), indicating the potential to prevent senescence. A higher apoptotic activity was observed in old rats compared with young rats, whereas LF 4189 reduced the expression of four antioxidative enzyme genes that function as radical scavengers (all P<0.05), suggesting that the LF 4189 group had a reduced need to scavenge free radicals. Our findings indicate the potential of probiotics, such as LF 4189, as an anti-aging dietary intervention with antioxidant potential to improve skin health.