Molecular Nutrition & Food Research

Vast and complex intestinal communities are regulated and balanced through interactions with their host organisms, and disruption of gut microbial balance can cause a variety of diseases. Studying the mechanisms of pathogenic intestinal flora in the host and early detection of bacterial translocation and colonization can guide clinical diagnosis, provide targeted treatments, and improve patient prognosis. The use of in vivo imaging techniques to track microorganisms in the intestine, and study structural and functional changes of both cells and proteins, may clarify the governing equilibrium between the flora and host...

Alzheimer's disease (AD) is the most prevailing form of dementia, with long-term high-fat diet (HFD) consumption being a pivotal contributor to AD pathogenesis. As microglial dysfunction is a crucial factor in the AD onset, it becomes imperative to explore the effects of HFD on microglial function and AD pathogenesis. In the present study, 3xTg-AD model mice at the age of 9-month are subjected to random allocation, with one group receiving a standard diet (ND) and the other an HFD for 3 months. Subsequently, transcriptomic profiling of microglia unveils that HFD alters fatty acid metabolism and mediates T cell infiltration...

SCOPE: This study examines whether coingestion of γ-aminobutyric acid (GABA) and malic acid (MA) before meals enhances glucagon-like peptide-1 (GLP-1) secretion, and which affects subsequent insulin and glycemic responses in humans. METHODS AND RESULTS: Initially, a murine enteroendocrine STC-1 cell line is used to verify coadministration of GABA and MA synergistically induces GLP-1 secretion. Next, 22 healthy adults are given water (50 mL) containing 400 mg GABA and 400 mg MA (Test), or only 400 mg citric acid (CA) (Placebo) 20 min before meal tolerance test (MTT)...

Alzheimer's disease (AD) and Parkinson's diseases (PD) are the two most common progressive neurodegenerative diseases with limited knowledge on their cause and, presently, have no cure. There is an existence of multiple treatment methods that target only the symptoms temporarily and do not stop the progression or prevent the onset of disease. Neurodegeneration is primarily attributed to the natural process of aging and the deleterious effects of heightened oxidative stress within the brain, whether via direct or indirect mechanisms...

SCOPE: Consumption of inulin could affect the intestinal microbiota composition. Hereby, it is aimed to investigate the intestinal microbial community restoration process when the inulin supplementation is terminated (i.e., the secondary effect). METHODS AND RESULTS: The current study investigates the response and restoration of intestinal microbiota to/after high (Inulin-H) and low (Inulin-L) dosage of inulin supplementation or sequential antibiotics and inulin (Anti-Inulin-L) supplementation, based on analysis of 16S rRNA gene sequences in C57BL/6 mice...

SCOPE: Gut microbiota (GM) dysbiosis and dysregulated bile acids (BAs) metabolism have been linked to ulcerative colitis (UC) pathogenesis. The possibility of utilizing live probiotics with a defined BAs-metabolizing capability to modify the composition BAs for UC treatment remains unexplored. METHODS AND RESULTS: In this study, Strain GR-4 is sourced from traditional Chinese fermented food, "Jiangshui," and demonstrated the ability to deconjugate two common conjugated BAs by over 69% and 98...

SCOPE: Urolithin A (UA), a gut-microbiota-derived metabolite of ellagic acid, presents various benefits to intestinal microecology. The presence of "gut-muscle axis" regulating the onset and progression of exercise-related physical frailty and sarcopenia has been recently hypothesized. This study aims to explore the underlying mechanism of gut-muscle axis by which UA enhances muscle strength and fatigue resistance of sleep-deprived (SD) mice. METHODS AND RESULTS: UA is gavaged to C57BL/6 mice (50 mg kg-1  bw) before 48-h SD...

SCOPE: Gut microbiota can convert a variety of alkaloids and TMAO into TMA, which is then transported by the blood to the liver, and converted into TMAO. In recent years, TMAO has attracted wide attention as a metabolic risk factor in cardiovascular disease, diabetes, and other diseases. However, it is still unclear about the role of gut microbial metabolite TMA in the adverse health impacts of TMAO. METHODS AND RESULTS: Male C57BL/6J is treated with intraperitoneal (i...

SCOPE: Endocannabinoid signaling regulates energy homeostasis, and is tightly associated with nonalcoholic fatty liver disease (NAFLD). The study previously finds that supplementation of docosahexaenoic acid (DHA) has superior function to ameliorate NAFLD compared with eicosapentaenoic acid (EPA), however, the underlying mechanism remains elusive. The present study aims to investigate whether DHA intervention alleviates NAFLD via endocannabinoid system. METHODS AND RESULTS: In a case-control study, the serum endocannabinoid ligands in 60 NAFLD and 60 healthy subjects are measured...

SCOPE: Dietary proteins and essential amino acids (EAAs) are the major nutritional supplements that support the growth and activity of gut microbes contributing to the wellbeing of their host. This study hypothesizes that daily supplementation of the diet with either EAAs or whey protein for 12 weeks would improve the gut microbiome of older adults. METHODS AND RESULTS: The stool samples are processed and subjected to Illumina-based 16S ribosomal ribonucleic acid (rRNA) gene amplicon sequencing...

SCOPE: Oxidative stress caused by iron overload tends to result in intestinal mucosal barrier dysfunction and intestinal microbiota imbalance. As a neutral and nonprotein amino acid, L-Citrulline (L-cit) has been implicated in antioxidant and mitochondrial amelioration properties. This study investigates whether L-cit can alleviate iron overload-induced intestinal injury and explores the underlying mechanisms. METHODS AND RESULTS: C57BL/6J mice are intraperitoneally injected with iron dextran, then gavaged with different dose of L-cit for 2 weeks...

As an important nutritional component, vitamin C (Vc) shows good antitumor activity in a variety of cancer, but there are few studies in pulmonary metastasis. In order to verify its anticancer and antimetastatic effect, the study sets up H22 pulmonary metastasis mouse model. The results show that intraperitoneal injection of Vc inhibits pulmonary metastasis through up-regulating the expression of Nrf2, HO-1, cleaved caspases 3 and 9, and causing DNA damage and apoptosis which is similar to the pro-oxidant effect of Vc in p53 null cells (H1299 cells)...

The discovery of metabolically active brown adipose tissue (BAT) in human adults and the worldwide increase in obesity and obesity-related chronic noncommunicable diseases (NCDs) has made BAT a therapeutic target in the last two decades. The potential of BAT to oxidize fatty acids rapidly and increase energy expenditure inversely correlates with adiposity, insulin and glucose resistance, and cardiovascular and metabolic diseases. Currently, BAT is recognized by a new molecular signature; several BAT-derived molecules that act positively on target tissues have been identified and collectively called batokines...

To investigate the efficacy of anserine on antiobesity, C57BL/6 mice are orally administered with a high-fat diet (HFD) and different doses of anserine (60, 120, and 240 mg/kg/day) for 16 weeks. Body weight, lipid, and epididymal fat content in mice are measured, and their liver damage is observed. The results display that the body weight, epididymal fat content, and low-density lipoprotein cholesterol (LDL-C) content in anserine groups are decreased by 4.36-18.71%, 7.57-35.12%, and 24.32-44.40%, respectively...

SCOPE: N-3 polyunsaturated fatty acids (n-3 PUFAs) play important roles in cognitive functions. However, there is a lack of knowledge on the metabolic impact of regio- and stereo-specific positioning of n-3 PUFAs in dietary triacylglycerols. METHODS AND RESULTS: Rats in a state of mild n-3 PUFA deficiency are fed daily with 360 mg triacylglycerols containing DHA (docosahexaenoic acid) at sn (stereospecific numbering)-1, 2, or 3 positions and 18:0 at remaining positions, or an equal amount of tristearin for 5 days...

SCOPE: The disturbance of the hypothalamic-pituitary-gonadal (HPG) axis, gut microbiota (GM) community, and short-chain fatty acids (SCFAs) is a triggering factor for pubertal onset. The study investigates the effects of the long-term intake of aspartame on puberty and GM in animals and humans. METHODS AND RESULTS: Aspartame-fed female offspring rats result in vaginal opening time prolongation, serum estrogen reduction, and serum luteinizing hormone elevation. , 60 mg kg-1 aspartame treatment decreases the mRNA levels of gonadotropin-releasing hormone (GnRH), Kiss1, and G protein-coupled receptor 54 (GPR54), increases the mRNA level of RFamide-related peptide-3 (RFRP-3), and decreases the expression of GnRH neurons in the hypothalamus...

SCOPE: Potato tubers represent an essential food component all over the world and an important supplier of carbohydrates, fiber, and valuable proteins. However, besides their health promoting effects, potatoes contain α-solanine and α-chaconine, which are toxic steroidal glycoalkaloids (SGAs). Other solanaceous plants like eggplants and tomatoes produce SGAs as well, different in their chemical structure. This study aims to investigate toxic effects (cholinesterase inhibition, membrane, and barrier disruption), permeability, metabolism, and structure-activity relationships of SGAs...

To explore the potential mechanism of action of Tegillarca granosa polysaccharide (TGP) in treating nonalcoholic fatty liver disease (NAFLD), the study conducts in vivo experiments using male C57BL/6 mice fed a high-fat diet while administering TGP for 16 weeks. The study measures body weight, liver weight, serum biochemical markers, pathological histology, liver lipid accumulation, oxidative stress and inflammation-related factors, lipid synthesis and metabolism-related gene and protein expression, and the composition and abundance of intestinal flora...

SCOPE: Diet and exercise are significant players in obesity and metabolic diseases. Time-restricted feeding (tRF) has been shown to improve metabolic responses by regulating circadian clocks but whether it acts synergically with exercise remains unknown. It is hypothesized that forced exercise alone or combined with tRF alleviates obesity and its metabolic complications. METHODS AND RESULTS: Male C57bl6 mice are fed with high-fat or a control diet for 12 weeks either ad libitum or tRF for 10 h during their active period...

SCOPE: To investigate the underlying mechanism of Astragaloside IV (AS-IV) in ameliorating diabetic nephropathy (DN) by regulating intestinal microbiota ecology and intestinal mucosal barrier. METHODS AND RESULTS: Genetically db/db mice are used to establish DN mouse model to monitor the therapeutic effects of AS-IV and fecal microbiota transplantation (FMT) against DN. Supplementation with AS-IV dramatically attenuates several clinical indicators of DN in db/db mice...