Alleviation of hepatic insulin resistance and steatosis with NMN via improving endoplasmic reticulum-Mitochondria miscommunication in the liver of HFD mice.

The interaction between endoplasmic reticulum (ER) and mitochondria has been shown to play a key role in hepatic steatosis during chronic obesity. ß-nicotinamide mononucleotide (NMN) has been reported to regulate obesity, however, its molecular mechanism at the subcellular level remains unclear. Here, NMN improved liver steatosis and insulin resistance in chronic high-fat diet (HFD) mice. RNA-seq showed that compared with the liver of HFD mice, NMN intervention enhanced fat digestion and absorption and stimulated the cholesterol metabolism signaling pathways, while impaired insulin resistance and the fatty acid biosynthesis signaling pathways. Mechanistically, NMN ameliorated mitochondrial dysfunction and ER oxidative stress in the liver of HFD mice by increasing hepatic nicotinamide adenine dinucleotide (NAD+) (P < 0.01) levels. This effect increased the contact sites (mitochondria-associated membranes [MAMs]) between ER and mitochondria, thereby promoting intracellular ATP (P < 0.05) production and mitigating lipid metabolic disturbances in the liver of HFD mice. Taken together, this study provided a theoretical basis for restoring metabolic dynamic equilibrium in the liver of HFD mice by increasing MAMs via the nutritional strategy of NMN supplementation.

Oleanolic acid alleviate intestinal inflammation by inhibiting Takeda G-coupled protein receptor (TGR) 5 mediated cell apoptosis.

Oleanolic acid (OA) is a bioactive compound present in plant-based foods known for its beneficial impact on gastrointestinal health, specifically in alleviating diarrhea. Nonetheless, the underlying mechanisms by which OA mitigates gut epithelial damage have yet to be elucidated. In this study, OA significantly markedly ameliorated adverse effects induced by Dextran Sulfate Sodium (DSS), including weight loss and epithelial morphological damage in a murine model. Remarkably, compared to normal mice, standalone administration of OA had no discernible impact on the animals. Concurrently, we identified a significant up-regulation in the expression levels of TGR5 and BAX in the intestines of DSS-exposed mice, coupled with a decline in Bcl2 expression. Correlation analyses revealed a robust association between TGR5 and BAX expression. Oral administration of OA efficaciously counteracted these alterations. To probe the role of TGR5 in cellular apoptosis, further, a lentivirus transfection approach was utilized to induce TGR5 overexpression in intestinal epithelial cells (IPEC-J2). RNA sequencing indicated that TGR5 overexpression significantly influenced biological processes, particularly in modulating cellular activation and intercellular adhesion, in contrast to the control group cells. Functional assays substantiated that TGR5 overexpression compromised cell viability and accelerated apoptosis. Notably, OA treatment in TGR5-overexpressed cells restored cell viability, suppressed TGR5 and BAX expression, and augmented Bcl2 expression. In sum, our data suggest that OA mitigates intestinal epithelial apoptosis and bolsters cellular proliferation by downregulating TGR5. This research provides valuable insights into the prospective utility of OA as a functional food supplement or adjunctive therapeutic agent for enhancing gastrointestinal health.

Bile Acid Metabolic Profiles and Their Correlation with Intestinal Epithelial Cell Proliferation and Barrier Integrity in Suckling Piglets.

Bile acids (BAs) are crucial for maintaining intestinal epithelial homeostasis. However, the metabolic changes in BAs and the communication between intestinal epithelial cells (IECs) in infants after birth remain unclear. This study aims to elucidate the BA profiles of newborn piglets (NPs) and suckling piglets (SPs), and to investigate their regulatory effects on IEC proliferation and barrier integrity, as well as the potential underlying mechanisms. In this study, compared with NPs, there were significant increases in serum triglycerides, total cholesterol, glucose, and albumin levels for SPs. The total serum BA content in SPs exhibited an obvious increase. Moreover, the expression of BA synthase cytochrome P450 27A1 (CYP27A1) was increased, and the ileal BA receptor Takeda G-coupled protein receptor 5 (TGR5) and proliferation marker Ki-67 were upregulated and showed a strong positive correlation through a Spearman correlation analysis, whereas the expression of farnesoid X receptor (FXR) and occludin was markedly downregulated in SPs and also revealed a strong positive correlation. These findings indicate that the increased synthesis and metabolism of BAs may upregulate TGR5 and downregulate FXR to promote IEC proliferation and influence barrier function; this offers a fresh perspective and evidence for the role of BAs and BA receptors in regulating intestinal development in neonatal pigs.

Stepwise co-fermented traditional Chinese medicine byproducts improve antioxidant and anti-inflammatory effects in a piglet model.

BACKGROUND: Lianhua Qingwen capsule is a traditional Chinese medicine (TCM) formula having antiviral and anti-inflammatory activities. During capsule production, a large amount of byproducts will be yielded and disposed of as waste by burying. Resourceful utilization of these kinds of TCM byproducts as feed additives through stage-based co-fermentation using enzyme and probiotics could reduce environmental stress and resource shortage. The in vitro characterization and the supplementary effects of fermented TCM byproducts (FTCM) for weaned piglets (initial body weight: 7.23 ± 0.33 kg; dose: basal diet + 300 mg kg-1 FTCM) were investigated. RESULTS: Higher reducing sugar content, total flavonoid content, flavonoid compounds (e.g. tectoridin, tricetin, flavone, apigenin, naringenin) and total antioxidant activity were determined in the FTCM compared to spontaneously fermented and unfermented materials. Supplementation of the FTCM to piglets did not significantly affect the feed intake, body weight gain and feed/gain ratio, but significantly decreased a proinflammatory cytokine, IL-8, and increased intestinal total antioxidant activity (TAC) and superoxide dismutase (SOD) activity. Moreover, FTCM supplementation increased α-diversity of the colonic microbiota accompanied with increased abundance of Prevotella genus and Treponema berlinense species. Correlation analysis indicates that T. berlinense is responsible for the decreased IL-8 level and enhanced intestinal TAC and SOD activities which might be mediated by a homoserine lactone molecule (3-oxo-C14). CONCLUSION: Overall, the stepwise co-fermentation enriched bioactive compounds within the TCM byproducts and their dietary supplementation did not generate any side effect on growth performance but displayed beneficial effects on enrichment of potential probiotic T. berlinense and relevant functions. © 2023 Society of Chemical Industry.

Dietary Eucommia ulmoides leaf extract improves laying performance by altering serum metabolic profiles and gut bacteria in aged laying hens.

The leaves of Eucommia ulmoides are rich in bioactive constituents that have potential gastrointestinal benefits for animals. In aged laying hens, intestinal health issues contribute to a significant decline in egg-laying capacity during intermediate and later stages. It remains unclear whether E. ulmoides leaf extract (ELE) can improve intestinal health and enhance egg production in elderly laying hens, and the underlying mechanisms are yet to be elucidated. Therefore, we conducted a study with 480 laying hens (65 weeks old) randomly allocated into four groups: a control group fed with the basal diet, and three treatment groups supplemented with 500, 1,000, and 2,000 mg/kg of ELE, respectively. The primary active constituents of ELE include flavonoids, polysaccharides, terpenoids, and phenolic acids. Dietary supplementation with ELE at 1,000 mg/kg (ELE1000) significantly improved laying performance and egg quality compared to the other groups. ELE1000 stimulated the maturation of intestinal epithelial cells, increased villus height, and reduced crypt depth. It also influenced the levels of proteins associated with tight junctions (claudin-1 and claudin-2) and intestinal inflammatory factors (IL-6, IL-1ß, and IL-2) in different intestinal sections. Integrative analysis of serum metabolomics and gut microbiota revealed that ELE1000 improved nutrient metabolism by modulating amino acid and ubiquinone biosynthesis and influenced the abundance of intestinal microbiota by enriching pivotal genera such as Bacteroides and Rikenellaceae_RC9_gut_group. We identified 15 metabolites significantly correlated with both gut microbiota and laying performance, e.g., DL-methionine sulfoxide, THJ2201 N-valerate metabolite, tetracarbonic acid, etc. In conclusion, ELE1000 improved laying performance in elderly laying hens by affecting intestinal morphology, barrier function, microbiota, and serum metabolite profiles. These findings suggest that ELE can be a beneficial feed additive for extending the peak producing period in aged laying hens.

In vitro antibacterial effects of Broussonetia papyrifera leaf extract and its anti-colitis in DSS-treated mice.

Recently, the hybrid Broussonetia papyrifera (BP) has been extensively cultivated and predominantly utilized in ruminants because of its high protein and bioactive compound content. In the present study, the effects of an ethanolic extract of BP leaves (BPE, 200 mg/kg) on mitigating 2% dextran sodium sulfate (DSS)-induced intestinal inflammation in mice were evaluated. BPE is rich in flavonoids, polyphenols, and polysaccharides, and displays potent antioxidant and antibacterial activities against pathogenic strains such as Clostridium perfringens, Salmonella Typhimurium, and Salmonella enterica subsp. enterica in vitro. In a mouse study, oral administration of DSS resulted in weight loss, incidence of diarrhea, enlargement of the liver and spleen, impaired colonic morphology, downregulation of both gene and protein expression related to intestinal antioxidant (Nrf2) and barrier function (ZO-1), decreased diversity of colonic microbiota, and 218 differentially altered colonic metabolites; however, co-treatment with BPE did not restore these modified aspects except for the liver index and colonic bacterial diversity. The singular treatment with BPE did not manifest evident side effects in normal mice but induced a mild occurrence of diarrhea and a notable alteration in the colonic metabolite profile. Moreover, a single BPE administration augmented the abundance of the commensal beneficial bacteria Faecalibaculum and Akkermansia genera. Overall, the extract of BP leaves did not demonstrate the anticipated effectiveness in alleviating DSS-induced intestinal inflammation.

Metagenomic characterization of the cecal microbiota community and functions in finishing pigs fed fermented Boehmeria nivea.

Ramie (Boehmeria nivea, BN) is used as livestock forage through suitable silage fermentation owing to its nutritional value. To date, relatively few studies have investigated the effects of dietary fermented BN (FBN) on gut health in finishing pigs. The aim of the present study was to investigate the effects of dietary supplementation with 20% FBN on intestinal morphology, gene expression, and the functional response of the gut microbiota in finishing pigs. We found that FBN did not significantly affect serum antioxidant enzyme activities, ileal morphology, or the expression of genes encoding antioxidant enzymes, inflammatory cytokines, or tight junction proteins in the liver of the pigs. However, the gene expression levels of aryl hydrocarbon receptor (AHR) and interleukin 6 (IL6) were significantly downregulated in the ileum. A metagenomic analysis demonstrated that, compared with that seen in the control group, the cecal microbiota of pigs in the FBN treatment group was more closely clustered and contained a greater number of unique microbes. Bacteria were the predominant kingdom in the cecal microbiota, while Firmicutes, Bacteroidetes, and Proteobacteria were the dominant phyla, and Streptococcus, Lactobacillus, and Prevotella were the dominant genera. Dietary FBN significantly increased the abundance of the probiotic bacterium Roseburia inulinivorans (p < 0.05). Functional analysis of the cecal microbiota showed that ABC transporter levels and glycolysis/gluconeogenesis-associated functions were diminished in FBN-fed pigs. Meanwhile, CAZyme analysis revealed that dietary FBN significantly downregulated the contents of carbohydrate-active enzymes, such as GT2, GH1, GH25, and GH13_31. In addition, cytochrome P450 analysis revealed that the abundance of CYP51 and CYP512 decreased with FBN treatment. An assessment of antibiotic resistance based on the Comprehensive Antibiotic Resistance Database (CARD) annotation indicated that the cecal microbes from pigs in the FBN treatment group had increased resistance to lincosamide, streptogramin, and chloramphenicol and reduced resistance to amikacin, isepamicin, neomycin, lividomycin, gentamicin, paromomycin, ribostamycin, and butirosin. Finally, virulence factor-related analysis showed that putative hemolysin-associated functions were decreased, whereas fibronectin-binding protein, flagella, and alginate-associated functions were increased. Taken together, our data showed that FBN supplementation exerted only minor effects on intestinal morphology and microbial community composition, suggesting that it is potentially safe for use as a supplement in the diets of finishing pigs. However, more studies are needed to validate its functionality.

Taurochenodeoxycholic acid inhibits intestinal epithelial cell proliferation and induces apoptosis independent of the farnesoid X receptor.

Bile acids, such as taurochenodeoxycholic acid (TCDCA), are considered as functional small molecules involved in nutrition regulation or acting with adjuvant therapeutic effects against metabolic or immune diseases. The homeostasis of the intestinal epithelium depends on the conventional cellular proliferation and apoptosis of cells. Herein, mice and normal intestinal epithelial cells (IPEC-J2, a widely used normal intestinal epithelial cell line derived from porcine) were used as models to explore the regulatory effect of TCDCA on the proliferation of intestinal epithelial cells (IECs). In the mouse study, the oral gavage of TCDCA led to a significant reduction in weight gain, small intestinal weight, and the villus height of the intestinal epithelium while inhibiting the gene expression of Ki-67 in the intestinal epithelial crypts of mice (P < 0.05). TCDCA significantly downregulated the expression of the farnesoid X receptor (FXR) and upregulated the expression of caspase-9 in the jejunum (P < 0.05). The results of real-time quantitative PCR (RT-qPCR) suggested that TCDCA significantly inhibited the expression of tight junction proteins zonula occludens (ZO)-1, occludin, claudin-1, and mucin-2 (P < 0.05). In terms of apoptosis-related genes, TCDCA significantly inhibited the expression of Bcl2 and increased the expression of caspase-9 (P < 0.05). At the protein level, TCDCA decreased the expression of Ki-67 and PCNA, as well as FXR (P < 0.05). Caspase inhibitor Q-VD-OPh and guggulsterone, an FXR antagonist, significantly improved the inhibition of TCDCA-induced cell proliferation. Moreover, guggulsterone enhanced TCDCA-induced cell late apoptosis through flow cytometry and significantly lowered the TCDCA-induced up-regulated gene expression of caspase 9, despite both TCDCA and guggulsterone down-regulating the expression of FXR (P < 0.05). Overall, the effect of TCDCA on the induction of apoptosis is not dependent on FXR, whereas it would function via the activation of the caspase system. This provides a new perspective for the application of TCDCA or bile acid as functional small molecules in food, additives, and medicine.

Evaluating the Effects of Polyphosphoric Acid (PPA) on the Anti-Ultraviolet Aging Properties of SBR-Modified Asphalt.

The ultraviolet (UV) aging of asphalt is an important factor affecting the long-term performance of asphalt pavement, especially in high altitude cold regions. The current studies have reported that styrene butadiene rubber-modified asphalt (SBRMA) has a good cracking resistance at low temperatures. In addition, polyphosphoric acid (PPA) is an effective modifier that can enhance the anti-UV aging properties of asphalt. However, the understanding of the improvement mechanism of PPA on the anti-aging of SBRMA remains unclear. Therefore, this study aimed to evaluate the effect of PPA on the UV aging resistance of SBRMA. The rheological properties of PEN90 asphalt(90#A), SBRMA, and PPA/SBR modified (PPA/SBR-MA) before and after UV aging were evaluated by dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests. The molecular weight and chemical structure of 90#A, SBRMA, and PPA/SBR-MA were determined by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC), and the interaction and modification mechanism of the modifiers were analyzed. The rheological analysis shows that the high and low temperature performances of SBRMA are improved by adding PPA, and PPA also significantly reduces the sensitivity of SBRMA to UV aging. The microscopic test results show that PPA has a complex chemical reaction with SBRMA, which results in changes in its molecular structure. This condition enhances SBRMA with a more stable dispersion system, inhibits the degradation of the polymer macromolecules of the SBR modifier, and slows down the aging process of base asphalt. In general, PPA can significantly improve the anti-UV aging performance of SBRMA. The Pearson correlations between the aging indexes of the macro and micro properties are also significant. In summary, PPA/SBRMA material is more suitable for high altitude cold regions than SBRMA, which provides a reference for selecting and designing asphalt pavement materials in high altitude cold regions.

Impact of fermented Broussonetia papyrifera on laying performance, egg quality, lipid metabolism, and follicular development of laying hens.

Hybrid Broussonetia papyrifera (BP) has been widely planted and commonly used as ruminant forage source after fermentation in China. Very less information is available to know the impact of fermented BP on laying hens, thus, we have investigated effects of dietary supplementation of Lactobacillus plantarum-fermented B. papyrifera (LfBP) on laying performance, egg quality, serum biochemical parameters, lipid metabolism, and follicular development of laying hens. A total of 288 HY-Line Brown hens (age, 23 wk) were randomly assigned into 3 treatment groups: control group (Con, a basal diet), LfBP1 and LfBP5 group (a basal diet supplemented with 1% or 5% LfBP). Each group has 8 replicates of twelve birds each. The results demonstrated that dietary supplementation of LfBP increased average daily feed intake (linear, P < 0.05), feed conversion ratio (linear, P < 0.05), and average egg weight (linear, P < 0.05) during the entire experimental period. In addition, dietary inclusion of LfBP enhanced the egg yolk color (linear, P < 0.01) but decreased the eggshell weight (quadratic, P < 0.05) and eggshell thickness (linear, P < 0.01). In serum, the LfBP supplementation linearly decreased the content of total triglyceride (linear, P < 0.01) but increased the content of high density lipoprotein-cholesterol (linear, P < 0.05). The gene expression related to hepatic lipid metabolism including acetyl-CoA carboxylase, fatty acid synthase, and peroxisome proliferator-activated receptor (PPARα) was down-regulated whereas liver X receptor was up-regulated in LfBP1 group. Moreover, LfBP1 supplementation remarkably reduced the F1 follicle number and ovarian gene expression of reproductive hormone receptors including estrogen receptor, follicle stimulating hormone receptor, luteinizing hormone receptor, progesterone receptor, prolactin receptor, and B cell lymphoma-2. In conclusion, dietary inclusion of LfBP could improve feed intake, egg yolk color, and lipid metabolism, but may cause a decline in eggshell quality with higher inclusion level, herein, 1% is suggested.

Effects of Anionic Emulsifiers and Emulsified Asphalt on Hydration and Microstructure of Cement.

Cement-emulsified asphalt (CEA) has been widely used in slab ballastless track and asphalt pavement cold recycling projects because of its high stiffness and toughness. In CEA material, emulsifiers and asphalt affect the cement's hydration process and microstructure. Thus, to further investigate the effects of anionic emulsifiers (AEs) and anionic emulsified asphalt (AEA) with different demulsification rates on the hydration process and microstructure of cement, two types of AE (rapid-setting and slow-setting) and their corresponding AEA were used to prepare modified cement pastes. First, it was confirmed that the AEs and AEA delayed cement hydration by measuring the setting time, X-ray diffraction (XRD) patterns, and electrical resistivity of the cement paste. Then, the microstructure of the cement paste was determined with mercury intrusion porosimetry (MIP) and a scanning electron microscope (SEM), and it was found that AEs and AEA have varying degrees of inhibitory effects on the formation of the cement paste microstructure. Finally, based on the energy dispersive spectrometer (EDS) element content of the cement paste and Fourier transform infrared spectroscopy (FTIR) on the two AEs, the inhibition mechanism of AE and AEA with different demulsifier rates on the cement hydration process was analyzed. The experimental results showed that both AEs and AEA delayed the hydration process of cement to varying degrees and altered the microstructure of cement, and slow setting anionic emulsified asphalt (SAEA) had the greatest impact on the hydration process and microstructure of cement. Compared to pure cement paste, the initial setting time of cement paste mixed with SAEA was delayed by 73.9%, and the final setting time was delayed by 66.7%. After adding SAEA, the most probable aperture of the cement paste increased from 62.50 nm to 71.19 nm after one day of hydration. Due to the fact that there were more carboxyl groups with negative charges, more -COO- was adsorbed onto the surface of cement particles in the slow-cracking anionic emulsifier (SAE); compared with the rapid-setting anionic emulsifier (RAE) and the rapid-setting anionic emulsified asphalt (RAEA), the SAE and the SAEA had a stronger delaying effect on the hydration reaction of cement.

Effects of Ambient Humidity on Water Migration and Hydrate Change in Early-Age Hardened Cement Paste.

Ultra-low humidity environments will lead to changes in the microstructure of C-S-H, which will reduce the mechanical properties and service life of cement-based concrete. Thus, to further explore the mechanism on the microscale, this paper studied the water migration and the changes in the hydration products in white cement that was cured for 7 days at 20 °C and at different ambient relative humidities (RHs). The migration and transformation of different types of water in cement paste were studied by low-field nuclear magnetic resonance (NMR). At the same time, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to analyze semi-quantitatively the crystal phase in the hydration products. The results showed that in the first 7 days of the curing process, the content of the different types of water and the hydration products in the cement samples were influenced by the ambient RH. The total water content of the samples will decrease with the decrease in the RH; when the RH decreases to 54% or below, the chemically bound water in the samples will increase with the decline in the RH. Additionally, when the ambient RH is lower than 54%, the grossular will gradually transform into hydrogrossular crystals with the decrease in the RH, and the hibschite with less chemically bound water will transform into katoite with more chemically bound water. In future research, the water migration and hydrate changes under different curing ages, drying processes, and coupling effects should be explored.

Nicotinamide mononucleotide supplementation protects the intestinal function in aging mice and D-galactose induced senescent cells.

The nicotinamide adenine dinucleotide (NAD+) level shows a temporal decrease during the aging process, which has been deemed as an aging hallmark. Nicotinamide mononucleotide (NMN), a key NAD+ precursor, shows the potential to retard the age-associated functional decline in organs. In the current study, to explore whether NMN has an impact on the intestine during the aging process, the effects of NMN supplementation on the intestinal morphology, microbiota, and NAD+ content, as well as its anti-inflammatory, anti-oxidative and barrier functions were investigated in aging mice and D-galactose (D-gal) induced senescent IPEC-J2 cells. The results showed that 4 months of NMN administration had little impact on the colonic microbiota and NAD+ content in aging mice, while it significantly increased the jejunal NAD+ content and improved the jejunal structure including increasing the villus length and shortening the crypt. Moreover, NMN supplementation significantly up-regulated the mRNA expression of SIRT3, SIRT6, nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), the catalytic subunit of glutamate-cysteine ligase (GCLC), superoxide dismutase 2 (SOD2), occludin, and claudin-1, but down-regulated the mRNA expression of tumor necrosis factor alpha (TNF-α). Specifically, in the D-gal induced senescent IPEC-J2 cells, 500 µM NMN restored the increased mRNA expression of interleukin 6 (IL6ST), IL-1A, nuclear factor (NF-κB1), and claudin-1 to normal levels to some extent. Furthermore, NMN treatment significantly affected the mRNA expression of antioxidant enzymes including NQO1, GCLC, SOD 2 and 3, and GSH-PX1, 3 and 4. In addition, 200 µM NMN enhanced the cell viability and total antioxidant capacity and lowered the reactive oxygen species level of senescent IPEC-J2 cells. Notably, NMN restored the down-regulated protein expression of occludin and claudin-1 induced by D-gal. The above data demonstrated the potential of NMN in ameliorating the structural and functional decline in the intestine during aging.

Effect of Metakaolin on the Microstructural and Chloride Ion Transport Properties of Concrete in Ocean Wave Splashing Zones.

In order to address the problem of the durability deficiency of concrete in wave splash zones in a harsh marine environment, this paper investigates the effects of coupled carbonation, sulfate, and chloride salts on the strength, capillary water absorption, and ion migration properties of cement concrete incorporated with metakaolin, and characterizes the pore structural changes with the mercury-pressure method and AC impedance technique. The results show that, compared with a single chloride salt environment, the improvement in mortar strength and impermeability with carbonation coupling is almost positively correlated with the calcium content in the specimen, and renders its pore structure more refined and denser. In contrast, the presence of sulfate reduces mortar strength and increases the ion migration coefficient. When the three factors of sulfate, carbonation, and chloride salt were coupled, damage to the strength and pore structure of the specimens was the most significant, but the specimen incorporated with 30% metakaolin had its strength improved compared with the blank group specimen; from the perspective of pore structural parameters and transport coefficient, the microstructure was denser, and the impermeability was significantly improved.

The Impacts of Short-Term NMN Supplementation on Serum Metabolism, Fecal Microbiota, and Telomere Length in Pre-Aging Phase.

Aging is a natural process with concomitant changes in the gut microbiota and associate metabolomes. Beta-nicotinamide mononucleotide, an important NAD+ intermediate, has drawn increasing attention to retard the aging process. We probed the changes in the fecal microbiota and metabolomes of pre-aging male mice (C57BL/6, age: 16 months) following the oral short-term administration of nicotinamide mononucleotide (NMN). Considering the telomere length as a molecular gauge for aging, we measured this in the peripheral blood mononuclear cells (PBMC) of pre-aging mice and human volunteers (age: 45-60 years old). Notably, the NMN administration did not influence the body weight and feed intake significantly during the 40 days in pre-aging mice. Metabolomics suggested 266 upregulated and 58 downregulated serum metabolites. We identified 34 potential biomarkers linked with the nicotinamide, purine, and proline metabolism pathways. Nicotinamide mononucleotide significantly reduced the fecal bacterial diversity (p < 0.05) with the increased abundance of Helicobacter, Mucispirillum, and Faecalibacterium, and lowered Akkermansia abundance associated with nicotinamide metabolism. We propose that this reshaped microbiota considerably lowered the predicated functions of aging with improved immune and cofactors/vitamin metabolism. Most notably, the telomere length of PBMC was significantly elongated in the NMN-administered mice and humans. Taken together, these findings suggest that oral NMN supplementation in the pre-aging stage might be an effective strategy to retard aging. We recommend further studies to unravel the underlying molecular mechanisms and comprehensive clinical trials to validate the effects of NMN on aging.

Policosanol alleviates hepatic lipid accumulation by regulating bile acids metabolism in C57BL6/mice through AMPK-FXR-TGR5 cross-talk.

Policosanol exhibits a lipid accumulation alleviating effect, but the underlying mechanisms remains unclear. Bile acids are a significant factor in regulating cholesterol and lipid metabolism homeostasis in mammals. This study was aimed to elucidate the alleviating effect and underlying mechanisms of policosanol on hepatic lipid accumulation through bile acid (BA) metabolism. Policosanol supplementation significantly reduced hepatic triglycerides (19.29%), cholesterol (30.38%) in high fat diet (HFD) induced obese mice (P < 0.05). Furthermore, compared with the control group, HFD decreased the levels of total BAs (TBAs, 37.67%) and cholic acid (CA, 62.74%) in the serum of mice (P < 0.05). Meanwhile, compared to HFD group, policosanol also increased the level of secondary BAs (SBAs) and muricholic acids (MCAs, P < 0.05). qRT-PCR combined with protein level analysis revealed that policosanol significantly decreased sterol regulatory element-binding protein (SREBP-1c) and CD36, and increased the expression level of cytochrome P450 family 7 subfamily A member 1 (CYP7A1) and cytochrome P450 Family 27 Subfamily A Member 1 (CYP27A1, P < 0.05). Additionally, in the liver, policosanol was found downregulated the expression of farnesoid X receptor (FXR)-small heterodimer partner (SHP), and activate the Takeda G-coupled protein receptor 5 (TGR5)-adenosine-monophosphate-activated protein kinase (APMK) signaling pathway (P < 0.05). Peroxisome proliferator activated receptor (PPAR)-α, hormone sensitive lipase (HSL), and carnitine palmitoyltransferase (CPT)-1α also significantly increased in HP group (P < 0.05). The aforementioned results reveal that the potential mechanism of policosanol in alleviating liver lipid accumulation is to promote BA synthesis and lipolysis through regulating the cross-talk of the AMPK-FXR-TGR5. New insight for the application of policosanol as an anti-fatty liver functional food ingredient or supplement is also provided. PRACTICAL APPLICATION: Policosanol is an important active component of cereals and insect waxes (15-80%). However, almost no policosanol in refined foods such as clear corn germ oil and wheat flour. This study showed that oral administration of policosanol can significantly reduce triglyceride and cholesterol levels in the liver through affecting AMPK-TGR5-FXR cross-talk, whereas no significant toxicological effect is reported in human and mouse models. This study may provide theoretical support for the theory of dietary structure and the development of dietary supplements to improve lipid metabolism targeting the "bile acid-AMPK-TGR5" pathway.

Extraction Techniques, Biological Activities and Health Benefits of Marine Algae Enteromorpha prolifera Polysaccharide.

There is increasing interest in the use of marine algae as functional food additives for improving human health. Enteromorpha (Ulva) prolifera (E. prolifera) is a seaweed green alga (Chlorophyta) that contains many bioactive compounds, of which polysaccharide is the main component. With the advancement of technology in the methods of extraction and analysis, recent studies in in vitro and animals model showed that polysaccharides derived from E. prolifera exert various biological activities, such as gut microbiota modulation, immunomodulation, antioxidant, antidiabetic, antimicrobial, and hypolipidemic. Research evidence has shown that methods of extraction and molecular modification, such as degradation, carboxymethylation, and sulfonation could alter the biological activities of polysaccharides. Therefore, in this review, we discussed the different extraction techniques, structural-activity relationship, and health benefits of sulfated polysaccharides derived from E. prolifera, and suggested future research avenues. This review helps to advance the extraction techniques and promote the application of marine algae polysaccharides as functional food and therapeutic agent.

Integrated Metagenomics and Metabolomics to Reveal the Effects of Policosanol on Modulating the Gut Microbiota and Lipid Metabolism in Hyperlipidemic C57BL/6 Mice.

The aim of the study was to investigate the regulatory effects of policosanol on hyperlipidemia, gut microbiota and metabolic status in a C57BL/6 mouse model. A total of 35 C57BL/6 mice were assigned to 3 groups, chow (n=12), high fat diet (HFD, n=12) and HFD+policosanol (n=11), then treated for 18 weeks. Policosanol supplementation significantly reduced serum triglycerides and total cholesterol, as well as the weight of brown adipose tissue (BAT) (p<0.05), without affecting body weight in HFD-fed mice (p>0.05). Combined 16S rRNA gene sequencing and untargeted metabolomic analysis demonstrated that policosanol had regulatory effects on gut microbiota and serum metabolism in mice. In obese mice, policosanol increased the proportion of Bacteroides, decreased the proportion of Firmicutes, and increased the ratio of Bacteroides to Firmicutes (p<0.05). Policosanol promoted lipolysis and thermogenesis process, including tricarboxylic acid (TCA) cycle and pyruvate cycle, correlated with the increasing level of Bacteroides, Parasutterella, and decreasing level of Lactobacillus and Candidatus_Saccharimonas. Moreover, policosanol decreased fatty acid synthase (FAS) in the iWAT of obese mice. Policosanol also increased peroxisome proliferators-activated receptor-γ (PPARγ), uncoupling Protein-1 (UCP-1), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) and PR domain containing 16 (PRDM16) in brown adipose tissue (BAT) obese mice (p<0.05). This study presents the new insight that policosanol may inhibit the synthesis of fatty acids, and promote lipolysis, thermogenesis related gene expression and regulate gut microbiota constituents, which provides potential for policosanol as an antihyperlipidemia functional food additive and provide new evidence for whole grain food to replace refined food.

The Gut Microbiota-Bile Acids-TGR5 Axis Mediates Eucommia ulmoides Leaf Extract Alleviation of Injury to Colonic Epithelium Integrity.

Eucommia ulmoides leaves (EL) are rich in phenolic acids and flavonoids, showing enhancing intestinal health effects. The intestinal microbiota-bile acid axis plays important roles in the occurrence and recovery of inflammatory bowel disease (IBD). However, whether EL extract (ELE) has regulatory effects on the intestinal microbiota, bile acid metabolism, and IBD is still unclear. To fill this gap, 2% dextran sulfate sodium (DSS)-induced mild IBD in a C57BL/6J mouse model that was treated with 200 or 400 mg/kg (intake dose/body weight) ELE was used. Oral ELE supplementation alleviated DSS-induced shortening of colon and colonic epithelial injury. Compared with the DSS group, ELE supplementation significantly decreased Toll-like receptor 4 (TLR4) and interlukin-6 (IL-6) and increased occludin and claudin-1 mRNA expression level in the colon (p < 0.05). Combined 16S rRNA gene sequencing and targeted metabolomic analyses demonstrated that ELE significantly improved the diversity and richness of the intestinal microbiota, decreased the abundance of Bacteroidaceae, and increased Akkermansiaceae and Ruminococcaceae abundance (p < 0.05) compared with DSS-induced IBD mice. Moreover, ELE significantly increased the serum contents of deoxycholic acid (DCA) and tauroursodeoxycholic acid (TUDCA), which were highly positively correlated with Akkermansia and unidentified_Ruminococccaceae relative to the DSS group. We then found that ELE increased Takeda G-protein coupled receptor 5 (TGR5), claudin-1, and occludin mRNA expression levels in the colon. In the Caco-2 cell model, we confirmed that activation of TGR5 improved the reduction in transepithelial electoral resistance (TEER) and decreased the permeability of FITC-dextran on monolayer cells induced by LPS (p < 0.05). siRNA interference assays showed that the decrease in TGR5 expression led to the decrease in TEER, an increase in FITC-dextran permeability, and a decrease in claudin-1 protein expression in Caco-2 cells. In summary, ELE alleviated IBD by influencing the intestinal microbiota structure and composition of bile acids, which in turn activated the colonic TGR5 gene expression in the colon and promoted the expression of tight junction proteins. These findings provide new insight for using ELE as a functional food with adjuvant therapeutic effects in IBD.

Enteromorpha polysaccharide-zinc replacing prophylactic antibiotics contributes to improving gut health of weaned piglets.

This research aimed to study whether Enteromorpha polysaccharide-zinc (EP-Zn) can act as an alternative to antibiotics in weaned piglet feeds. Two hundred and twenty-four weaned piglets from 14 pens were randomly assigned into 1 of 2 groups according to their body weight and litter size (7 pens/group). The piglets in the antibiotics group were fed with olaquindox at 400 mg/kg and enduracidin at 800 mg/kg basal diet, and piglets in the EP-Zn group were fed with EP-Zn at 800 mg/kg basal diet. One piglet per pen was selected to collect samples after 14 d of feeding. Results showed that EP-Zn supplementation significantly increased the plasma anti-oxidants level compared with the antibiotics group. However, a nonsignificant difference was observed in growth performance between treatment groups. Additionally, the intestinal tight junction (TJ) protein expression and the histopathologic evaluation data showed that EP-Zn contributed to improving intestinal development. Further, piglets in the EP-Zn group had a lower level of intestinal inflammation-related cytokines including IL-6 (P < 0.001), IL-8 (P < 0.05), IL-12 (P < 0.05) and tumor necrosis factor-α (TNF-α) (P < 0.001), and showed an inhibition of the phosphorylation nuclear transcription factor-kappa B (p-NF-κB) (P < 0.05) and total NF-κB (P < 0.001) level in the jejunal mucosa. Taken together, it is supposed that EP-Zn, to some extent, would be a potent alternative to prophylactic antibiotics in improving the health status of weaned piglets.