Preventive Effect of Apple Polyphenol Extract on High-Fat Diet-Induced Hepatic Steatosis in Mice through Alleviating Endoplasmic Reticulum Stress

Development of active film based on collagen and hydroxypropyl methylcellulose incorporating apple polyphenol for food packaging

Collagen (COL)-hydroxypropyl methylcellulose (HPMC) blended films with apple polyphenol (AP) as cross-linking agent and antioxidant compound were developed to produce biodegradable active packaging film. The effects of AP content on the rheological behavior of the blended solution, the structure, physicochemical and functional properties of the blended film were systematically investigated. The incorporation of AP increased the viscosity and reduced the fluidity of COL-HPMC solution. The results of rheological tests and FTIR analysis manifested the formation of hydrogen bonding interactions between collagen, HPMC and AP, which made the structures of COL-HP-AP films more compact. The mechanical strength, UV-blocking ability, water-resistance performance and thermostability were gradually enhanced as increasing AP content. DPPH free radical scavenging experiment showed that a small amount of AP could efficiently improve the antioxidant activity of COL-HP film, and with increasing AP content to 5 wt%, the scavenging rate was as high as 94.23 %. Active film containing 5 wt% AP showed obvious antibacterial effect on E. coli and S. aureus, and it could effectively prevent the oxidation of vitamin C and reduce the accumulation of MDA on green pepper during the storage. COL-HP-AP films have great potential in food packaging field for extending the shelf life of food.

Thinned young apple powder prevents obesity-induced neuronal apoptosis via improving mitochondrial function of cerebral cortex in mice

Mitochondrial dysfunction is one of the triggers for obesity-induced neuron apoptosis. Thinned young apple is getting more attention on account of the extensive biological activities because of rich polyphenols and polysaccharides. However, the neuroprotective effect of thinned young apple powder (YAP) is still unclear. The aim of the present study was to investigate the preventive effect of YAP on obesity-induced neuronal apoptosis. C57BL/6J male mice were divided into 5 groups, control (CON), high fat diet (HFD), HFD + orlistat (ORL), HFD + low-dose young apple powder (LYAP) and HFD + high-dose young apple powder (HYAP) groups and intervened for 12 weeks. It was found that the YAP effectively reduced body weight gain. Importantly, the levels of pro-apoptosis protein were lower in LYAP and HYAP groups than the HFD group, such as Bak/Bcl2 and cleaved caspase3/caspase3. Pathway analysis based on untargeted metabolomics suggested that YAP alleviated obesity-induced neuronal apoptosis by three main metabolic pathway including arginine metabolism, citrate cycle (TCA cycle) and glutathione metabolism. Meanwhile, YAP improved the protein expression of mitochondrial respiratory chain complex, maintained the homeostasis of TCA cycle intermediates, protected the balance of mitochondrial dynamics and alleviated lipid accumulation. In addition, the levels of several antioxidants in cerebral cortex were higher in HYAP group than the HFD group like superoxide dismutase (SOD) and catalase (CAT). In summary, YAP supplementation suppressed neuronal apoptosis in the cerebral cortex of HFD-induced obesity mice by improving mitochondrial function and inhibiting oxidative stress.

Gut microbiota-metabolic axis insight into the hyperlipidemic effect of lotus seed resistant starch in hyperlipidemic mice

We investigated the hyperlipidemic effect of different doses of lotus seed resistant starch (low-, medium and high-dose LRS, named as LLRS, MLRS and HLRS, respectively) in hyperlipidemic mice using gut microbiota-metabolic axis compared to high-fat diet mice (model control group, MC). Allobaculum was significantly decreased in LRS groups compared to MC group, while MLRS promoted the abundance of norank_f_Muribaculaceae and norank_f_Erysipelotrichaceae. Moreover, supplementation of LRS promoted cholic acid (CA) production and inhibited deoxycholic acid compared to MC group. Among, LLRS promoted formic acid, MLRS inhibited 20-Carboxy-leukotriene B4, while HLRS promoted 3, 4-Methyleneazelaic acid and inhibited Oleic acid and Malic acid. Finally, MLRS regulate microbiota composition, and this promoted cholesterol catabolism to form CA, which inhibited serum lipid index by gut microbiota-metabolic axis. In conclusion, MLRS can promote CA and inhibit medium chain fatty acids, so as to play the best role in lowering blood lipids in hyperlipidemia mice.

Ellagic Acid Prevents Particulate Matter-Induced Pulmonary Inflammation and Hyperactivity in Mice: A Pilot Study

The inhalation of fine particulate matter (PM) is a significant health-related environmental issue. Previously, we demonstrated that repeated PM exposure causes hyperlocomotive activity in mice, as well as inflammatory and hypoxic responses in their lungs. In this study, we evaluated the potential efficacy of ellagic acid (EA), a natural polyphenolic compound, against PM-induced pulmonary and behavioral abnormalities in mice. Four treatment groups were assigned in this study (n = 8): control (CON), particulate-matter-instilled (PMI), low-dose EA with PMI (EL + PMI), and high-dose EA with PMI (EH + PMI). EA (20 and 100 mg/kg body weight for low dose and high dose, respectively) was orally administered for 14 days in C57BL/6 mice, and after the eighth day, PM (5 mg/kg) was intratracheally instilled for 7 consecutive days. PM exposure induced inflammatory cell infiltration in the lungs following EA pretreatment. Moreover, PM exposure induced inflammatory protein expression in the bronchoalveolar lavage fluid and the expression of inflammatory (tumor necrosis factor alpha (Tnfα), interleukin (Il)-1b, and Il-6) and hypoxic (vascular endothelial growth factor alpha (Vegfα), ankyrin repeat domain 37 (Ankrd37)) response genes. However, EA pretreatment markedly prevented the induction of expression of inflammatory and hypoxic response genes in the lungs. Furthermore, PM exposure significantly triggered hyperactivity by increasing the total moving distance with an increase in moving speed in the open field test. On the contrary, EA pretreatment significantly prevented PM-induced hyperactivity. In conclusion, dietary intervention with EA may be a potential strategy to prevent PM-induced pathology and activity.

Folic Acid Protects against Hyperuricemia in C57BL/6J Mice via Ameliorating Gut-Kidney Axis Dysfunction

Emerging lines of research evidence point to a vital role of gut-kidney axis in the development of hyperuricemia (HUA), which has been identified as an increasing burden worldwide due to the high prevalence. The involved crosstalk which links the metabolic and immune-related pathways is mainly responsible for maintaining the axial homeostasis of uric acid (UA) metabolism. Nowadays, the urate-lowering drugs only aim to treat acute gouty arthritis as a result of their controversial clinical application in HUA. In this study, we established the HUA model of C57BL/6J mice to evaluate the effectiveness of folic acid on UA metabolism and further explored the underlying mechanisms. Folic acid attenuated the kidney tissue injury and excretion dysfunction, as well as the typical fibrosis in HUA mice. Molecular docking results also revealed the structure-activity relationship of the folic acid metabolic unit and the UA transporters GLUT9 and URAT1, implying the potential interaction. Also, folic acid alleviated HUA-induced Th17/Treg imbalance and intestinal tissue damage and inhibited the active state of the TLR4/NF-κB signaling pathway, which is closely associated with the circulating LPS level caused by the impaired intestinal permeability. Furthermore, the changes of intestinal microecology induced by HUA were restored by folic acid, including the alteration in the structure and species composition of the gut microbiome community, and metabolite short-chain fatty acids. Collectively, this study revealed that folic acid intervention exerted improving effects on HUA by ameliorating gut-kidney axis dysfunction.

Folic acid ameliorates alcohol-induced liver injury via gut–liver axis homeostasis

The gut–liver axis (GLA) plays an important role in the development of alcohol-induced liver injury. Alcohol consumption is typically associated with folic acid deficiency. However, no clear evidence has confirmed the effect of folic acid supplementation on alcohol-induced liver injury via GLA homeostasis. In this study, male C57BL/6J mice were given 56% (v/v) ethanol and 5.0 mg/kg folic acid daily by gavage for 10 weeks to investigate potential protective mechanisms of folic acid in alcohol-induced liver injury via GLA homeostasis. Histopathological and biochemical analyses showed that folic acid improved lipid deposition and inflammation in the liver caused by alcohol consumption and decreased the level of ALT, AST, TG, and LPS in serum. Folic acid inhibited the expression of the TLR4 signaling pathway and its downstream inflammatory mediators in the liver and upregulated the expression of ZO-1, claudin 1, and occludin in the intestine. But compared with the CON group, folic acid did not completely eliminate alcohol-induced intestine and liver injury. Furthermore, folic acid regulated alcohol-induced alterations in gut microbiota. In alcohol-exposed mice, the relative abundance of Bacteroidota was significantly increased, and the relative abundance of unclassified_Lachnospiraceae was significantly decreased. Folic acid supplementation significantly increased the relative abundance of Verrucomicrobia, Lachnospiraceae_NK4A136_group and Akkermansia, and decreased the relative abundance of Proteobacteria. The results of Spearman’s correlation analysis showed that serum parameters and hepatic inflammatory cytokines were significantly correlated with several bacteria, mainly including Bacteroidota, Firmicutes, and unclassified_Lachnospiraceae. In conclusion, folic acid could ameliorate alcohol-induced liver injury in mice via GLA homeostasis to some extent, providing a new idea and method for prevention of alcohol-induced liver injury.

Garlic oil alleviates high triglyceride levels in alcohol-exposed rats by inhibiting liver oxidative stress and regulating the intestinal barrier and intestinal flora

Garlic oil (GO) is a kind of natural extract extracted from garlic, which has strong antioxidant activity. This study elucidates the protective mechanism of GO against alcohol-induced high triglyceride levels. Sixty male Sprague Dawley rats were assigned to five groups, including a control group (CON), a model group (MOD) treated with alcohol 56% v/v at 8 ml kg-1 day-1 for 2 weeks then 10 ml kg-1 day-1 for 8 weeks, a low-dose GO group (GO-L) given GO at 20 mg kg-1 day-1, a high-dose GO group (GO-H) given GO at 40 mg kg-1 day-1, and a positive group (POS) given diammonium glycyrrhizinate at 200 mg kg-1 day-1. The results showed that GO could significantly reduce the serum and liver triglyceride levels caused by alcohol exposure (p < .05). The GO-H group significantly reduced MDA level, increased SOD and GSH-Px levels in serum, liver, and colon (p < .05), significantly increased the levels of Sirt1 and PGC-1α proteins and reduced FoxO1 protein level in liver (p < .05), and significantly increased the levels of ZO-1 and Claudin1 proteins in the colon compared to the MOD group (p < .05). The 16S rRNA sequencing showed that the intestinal flora of the GO-H group was significantly changed compared with the MOD group. In summary, GO has the potential to improve high triglyceride levels in serum and liver induced by alcohol exposure, which may be related to the inhibition of oxidative stress regulation of Sirt1 and its downstream proteins, and to the restoration of the intestinal barrier and intestinal flora.

Protective effects of apple polyphenols on bone loss in mice with high fat diet-induced obesity

Obesity-induced inflammation can lead to an imbalance in bone formation and resorption. Our previous studies have demonstrated that apple polyphenols (AP) can reduce body weight and inflammation. But its effect...

Nicotinamide riboside ameliorates high-fructose-induced lipid metabolism disorder in mice via improving FGF21 resistance in the liver and white adipose tissue

NR supplementation could ameliorate high-fructose-induced lipid metabolism disorder by improving FGF21 resistance in the liver and WAT, which may be related to the inflammation state mediated by SIRT1/NF-κB signaling pathway.