Effects of Timing and Types of Protein Supplementation on Improving Muscle Mass, Strength, and Physical Performance in Adults Undergoing Resistance Training: A Network Meta-Analysis.

Precise protein supplementation strategies for muscle improvement are still lacking. The timing or type of protein supplementation has been debated as a window of opportunity to improve muscle mass, strength, and physical performance. We conducted a network meta-analysis of randomized controlled trials with protein supplements and resistance training. PubMed, Web of Science, Cochrane Library, and SPORTDiscus databases were searched until May 1, 2023. We included 116 eligible trials with 4,711 participants that reported on 11 timing and 14 types of protein supplementation. Compared with placebo, protein supplementation after exercise (mean difference [MD]: 0.54 kg [95% confidence intervals 0.10, 0.99] for fat-free mass, MD: 0.34 kg [95% confidence intervals 0.10, 0.58] for skeletal muscle mass) and at night (MD: 2.85 kg [0.49, 5.22] for handgrip strength, MD: 12.12 kg [3.26, 20.99] for leg press strength) was most effective in improving muscle mass and strength, respectively (moderate certainty). Milk proteins (milk, whey protein, yogurt, casein, and bovine colostrum), red meat, and mixed protein were effective for gains in both muscle mass and strength (moderate certainty). No timing or type of protein showed a significant enhancement in physical performance (timed up-to-go test, 6-min walk test, and gait speed). Pre/postexercise and Night are key recommended times of protein intake to increase muscle mass and strength, respectively. Milk proteins are the preferred types of protein supplements for improving muscle mass and strength. Future randomized controlled trials that directly compare the effects of protein timing or types are needed. This trial was registered at International Prospective Register of Systematic Reviews as CRD42022358766.

Effect of synbiotic supplementation on immune parameters and gut microbiota in healthy adults: a double-blind randomized controlled trial.

Synbiotics are increasingly used by the general population to boost immunity. However, there is limited evidence concerning the immunomodulatory effects of synbiotics in healthy individuals. Therefore, we conducted a double-blind, randomized, placebo-controlled study in 106 healthy adults. Participants were randomly assigned to receive either synbiotics (containing Bifidobacterium lactis HN019 1.5 × 108 CFU/d, Lactobacillus rhamnosus HN001 7.5 × 107 CFU/d, and fructooligosaccharide 500 mg/d) or placebo for 8 weeks. Immune parameters and gut microbiota composition were measured at baseline, mid, and end of the study. Compared to the placebo group, participants receiving synbiotic supplementation exhibited greater reductions in plasma C-reactive protein (P = 0.088) and interferon-gamma (P = 0.008), along with larger increases in plasma interleukin (IL)-10 (P = 0.008) and stool secretory IgA (sIgA) (P = 0.014). Additionally, synbiotic supplementation led to an enrichment of beneficial bacteria (Clostridium_sensu_stricto_1, Lactobacillus, Bifidobacterium, and Collinsella) and several functional pathways related to amino acids and short-chain fatty acids biosynthesis, whereas reduced potential pro-inflammatory Parabacteroides compared to baseline. Importantly, alternations in anti-inflammatory markers (IL-10 and sIgA) were significantly correlated with microbial variations triggered by synbiotic supplementation. Stratification of participants into two enterotypes based on pre-treatment Prevotella-to-Bacteroides (P/B) ratio revealed a more favorable effect of synbiotic supplements in individuals with a higher P/B ratio. In conclusion, this study suggested the beneficial effects of synbiotic supplementation on immune parameters, which were correlated with synbiotics-induced microbial changes and modified by microbial enterotypes. These findings provided direct evidence supporting the personalized supplementation of synbiotics for immunomodulation.

Current studies and potential future research directions on biological effects and related mechanisms of allicin.

Allicin, a thiosulfonate extract from freshly minced garlic, has been reported to have various biological effects on different organs and systems of animals and human. It can reduce oxidative stress, inhibit inflammatory response, resist pathogen infection and regulate intestinal flora. In addition, dozens of studies also demonstrated allicin could reduce blood glucose level, protect cardiovascular system and nervous system, and fight against cancers. Allicin was widely used in disease prevention and health care. However, more investigations on human cohort study are needed to verify the biological or clinical effects of allicin in the future. In this review, we summarized the biological effects of allicin from previous outstanding and valuable studies and provided useful information for future studies on the health effects of allicin.

Vitamin D status, genetic factors, and risks of cardiovascular disease among individuals with type 2 diabetes: a prospective study.

BACKGROUND: The presence of a threshold effect has been proposed, suggesting that beneficial effects from vitamin D supplementation may only be present when the vitamin D concentration is below a particular threshold. OBJECTIVES: We investigated the associations of serum 25-hydroxyvitamin D [25(OH)D] concentrations and genetic factors with risks of total and subtypes of cardiovascular disease (CVD) in individuals with type 2 diabetes (T2D), among whom vitamin D deficiency or insufficiency is particularly common. METHODS: This prospective study included 15,103 individuals with T2D who were initially free of CVD and had serum 25(OH)D measurements in the UK Biobank. Incidences of total and subtypes of CVD, including ischemic heart disease (IHD) and stroke, were ascertained via electronic health records. Weighted genetic risk scores (GRSs) were constructed for IHD and stroke. RESULTS: The mean serum 25(OH)D concentration was 43.4 nmol/L (SD: 20.4 nmol/L), and 65.7% of participants had a vitamin D concentration below 50 nmol/L. During a median of 11.2 years of follow-up, 3534 incident CVD events were documented. Compared with individuals with 25(OH)D concentrations <25 nmol/L, participants with 25(OH)D concentrations ≥75 nmol/L had HRs (95% CIs) of 0.75 (0.64, 0.88) for CVD, 0.69 (0.56, 0.84) for IHD, and 0.74 (0.52, 1.06) for stroke. Participants with 25(OH)D concentrations ≥50 nmol/L and low GRSs, as compared with individuals with 25(OH)D concentrations <25 nmol/L and high GRSs, had a 50% (39%, 65%) lower risk of IHD. No significant interactions were demonstrated between serum 25(OH)D concentrations and the GRSs and genetic variants in vitamin D receptors (VDR). CONCLUSIONS: Higher serum 25(OH)D concentrations were significantly associated with lower risks of total CVD and IHD among patients with T2D, regardless of their genetic susceptibility and the genetic variants in VDR. Risk reductions tended to plateau at serum 25(OH)D levels around 50 nmol/L. These findings suggest that maintaining an adequate vitamin D status and avoiding deficiency may help to prevent CVD complications among patients with T2D.

Effect of Plant-Derived n-3 Polyunsaturated Fatty Acids on Blood Lipids and Gut Microbiota: A Double-Blind Randomized Controlled Trial.

BACKGROUND: Several cardioprotective mechanisms attributed to n-3 polyunsaturated fatty acids (PUFAs) have been widely documented. Significant interest has recently focused on the role of human gut microbiota in metabolic disorders. However, the role of plant-derived n-3 PUFAs on blood lipid profiles is controversial and the effect on gut microbiota is still unclear. OBJECTIVES: We aimed to perform a double-blind randomized controlled trial to test the effect of plant-derived n-3 PUFAs on the blood lipids and gut microbiota of patients with marginal hyperlipidemia. METHODS: According to the inclusion and exclusion criteria, 75 participants with marginal hyperlipidemia were randomly assigned to the intervention group (supplied with n-3 PUFA-enriched plant oil) or control group (supplied with corn oil), respectively, for a 3-month treatment. Participants and assessors were blinded to the allocation. The primary outcomes of the trial were the changes in serum lipid levels. Secondary outcomes were changes in gut microbiota and metabolites. For the primary outcomes, we conducted both an intent-to-treat (ITT) analysis and a per protocol (PP) analysis. For the secondary outcomes, we only conducted the PP analysis among the participants who provided fecal sample. RESULTS: Fifty-one participants completed the trial. Relative to the control group, the n-3 PUFA supplementation resulted in significant reduction in total cholesterol (TC) levels (-0.43 mmol/L, 95% CI-0.84 to-0.01 mmol/L, P < 0.05). The n-3 PUFA supplementation was also associated with significantly increased relative abundance of Bacteroidetes in phylum level (P < 0.01; false discovery rate (FDR) corrected p = 0.11), and decreased the ratio between Firmicutes and Bacteroidetes (P < 0.05; FDR corrected p = 0.16). At genus level, the intervention of plant derived n-3 PUFAs resulted in a significant decrease in relative abundance of Phascolarctobacterium (P < 0.01; FDR corrected p = 0.18) and Veillonella (P < 0.01; FDR corrected p = 0.18) after the intervention. CONCLUSIONS: Our results demonstrated that plant-derived n-3 PUFAs beneficially affected the serum levels of TC and decreased the ratio between Firmicutes and Bacteroidetes during the 12-week intervention period, which might confer advantageous consequences for lipid metabolism and intestinal health.

Non-coding RNAs-associated ceRNA networks involved in the amelioration of skeletal muscle aging after whey protein supplementation.

Whey protein has been reported to be an impactful dietary supplement to ameliorate skeletal muscle aging for a long time. However, whether whey protein could contribute to muscle aging amelioration by post-transcriptional modulation remains unclear. In this study, 19-month-old mice orally received whey protein supplementation (1.0 g/kg/bw/d, whey protein group) or deionized water (the control group) for 3 months. Differentially expressed ncRNAs and mRNAs in quadriceps were identified by RNA-seq. Construction of non-coding RNAs (ncRNAs)-associated competing endogenous RNA (ceRNA) networks as well as GO and KEGG enrichment analyses were also carried out subsequently. Meanwhile, ultrasound measurement, H&E staining, myofiber cross-sectional area measurement, western blotting and RT-qPCR were performed in the quadriceps to evaluate muscle status and verify the RNA-seq data. Whey protein supplementation for 3 months increased quadriceps-body weight ratio and improved the histological as well as ultrasonographic characteristics of aging in muscle. Moreover, the protein expression levels of Myog, Myf4, Myf5 and MyoD1 were all significantly elevated in quadriceps. The expression of 90 lncRNAs, 334 mRNAs, six circRNAs and 52 miRNAs were significantly up or down-regulated in quadriceps after whey protein supplementation. Furthermore, ncRNAs-associated networks and GO and KEGG enrichment analyses revealed whey protein may influence muscle aging process through selected ncRNAs-associated ceRNA networks. Therefore, post-transcriptional modulation could be a potential crucial way to ameliorate skeletal muscle aging after whey protein supplementation. The selected ncRNAs-associated ceRNA networks may provide new insight for the underlying mechanism and profound therapeutic target for skeletal muscle aging.

Serum selenium concentrations and risk of all-cause and heart disease mortality among individuals with type 2 diabetes.

BACKGROUND: The impact of selenium status on the long-term health of people with type 2 diabetes (T2D) remains unclear. OBJECTIVES: To prospectively examine the association of serum selenium concentrations with all-cause and heart disease mortality among individuals with T2D. METHODS: This analysis included 3199 adults with T2D from the third NHANES (NHANES III) and NHANES (2003-2004, 2011-2014). Mortality from heart disease and all causes was linked to National Death Index mortality data. Cox proportional hazard models were used to estimate HRs and 95% CIs. RESULTS: The median (IQR) concentration of serum selenium was 127.0 (115.0, 139.1) µg/L. During an average 12.6-y follow-up, 1693 deaths were documented, including 425 heart disease deaths. Compared with participants in the lowest quartile of selenium, the multivariate-adjusted HRs (95% CIs) for participants in the highest quartile were 0.69 (0.54, 0.89) for all-cause mortality (P-trend = 0.002) and 0.66 (0.45, 0.99) for heart disease mortality (P-trend = 0.03). In addition, a linear dose-response relation between serum selenium (range: 89-182 µg/L) and mortality was observed. For per-unit increment in natural log-transformed serum selenium, there was a 64% lower risk of all-cause mortality and a 66% lower risk of heart disease mortality (both P < 0.05). Similar results were observed when stratifying by age, sex, race, smoking status, BMI, physical activity, diabetes duration, and HbA1c concentrations. CONCLUSIONS: Our study suggested that higher selenium concentration was associated with lower all-cause and heart disease mortality among individuals with T2D. More studies are needed to confirm these findings.

Lutein attenuates excessive lipid accumulation in differentiated 3T3-L1 cells and abdominal adipose tissue of rats by the SIRT1-mediated pathway.

OBJECTIVE: Obesity is now a worldwide disease and is mainly attributable to increased body fat deposition. In a growing number of epidemiological studies, lutein has been revealed to have different degrees of anti-obesity properties, but the potential underlying mechanisms that have been reported are limited. Therefore, we aimed to clarify the protective effects of lutein against excessive lipid accumulation, and we explored the role of SIRT1 and SIRT1-mediated pathways both in abdominal adipose tissue and mature 3T3-L1 cells during lutein administration. METHODS: In our design, male Sprague-Dawley rats were fed either control or high-fat diets with or without 25 mg/kg·bw/day lutein for 5 weeks. Additionally, differentiated 3T3-L1 cells were incubated with 40 µM lutein or 10 µM Ex527 for 24 h. RESULTS: Lutein supplementation decreased the body weight, abdominal fat index ratio, frequency and mean area of larger adipocytes in HE staining induced by the high-fat diet and then activated the expression of SIRT1 and thus upregulated FoxO1, ATGL, and HSL expression and downregulated SREBP-1, FAS, and ACC expression both in abdominal adipose tissue and differentiated 3T3-L1 cells. However, coincubation with Ex527 and lutein suppressed the activation of SIRT1 and reversed the expression of FoxO1, ATGL, HSL, SREBP-1, FAS, and ACC in comparison to those in the Lut group. CONCLUSIONS: Overall, we suggest that the effects of lutein on attenuating excessive lipid accumulation are dependent on the SIRT1-mediated pathway in vivo and in vitro, which indicates that lutein administration may be a potential strategy for preventing excessive lipid accumulation and obesity.

Diverse Associations of Plasma Selenium Concentrations and SELENOP Gene Polymorphism with Metabolic Syndrome and Its Components.

The relationship between selenium and metabolic syndrome (MetS) has been discussed controversially, and limited studies have examined the associations of single nucleotide polymorphisms in selenoproteins genes with MetS. Hence, to examine the associations of plasma selenium concentrations and selenoprotein P rs7579 polymorphism with MetS, a case-control study of 1279 MetS cases and 1279 sex- and age- (±2 years) matched controls was conducted based on the baseline data of the Tongji-Ezhou Cohort study. Plasma selenium concentrations were measured by inductively coupled plasma mass spectrometry. MetS was defined using the definition of the Joint Interim Statement, adjusted for the Chinese population. In addition, the rs7579 polymorphism was genotyped by the Agena MassARRAY System. Plasma selenium concentrations in the MetS group were higher than in the control group (93.88 µg/L (83.17-107.41) vs. 92.66 µg/L (82.36-103.53), P < 0.05). Compared with quartile 4 (≥103.53 µg/L), the multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) associated with MetS were 0.79 (0.59-1.06) for quartile 1 (<82.36 µg/L), 0.75 (0.56-1.01) for quartile 2 (82.37-92.66 µg/L), and 0.61 (0.45-0.83) for quartile 3 (92.67-103.52 µg/L). The cubic spline analyses revealed a U-shaped association between plasma selenium and MetS, with the lowest risk at around 93.69 µg/L. Moreover, in cubic spline analyses, plasma selenium showed U-shaped associations with central obesity and high blood pressure, positive associations with hypertriglyceridemia and hyperglycemia, and a negative association with low high-density lipoprotein cholesterol. Additionally, both the GA and GA+AA genotype carriers were associated with increased ORs of MetS comparing with the GG genotype carriers. Our findings suggested a U-shaped association between plasma selenium and MetS and diverse associations between plasma selenium and components of MetS. Furthermore, our study found that the A allele of rs7579 was associated with higher odds of MetS. Further studies are needed to confirm our findings and elucidate the underlying mechanisms.

Effects of fish oil supplementation on glucose control and lipid levels among patients with type 2 diabetes mellitus: a Meta-analysis of randomized controlled trials.

BACKGROUND: Previous studies have yielded inconsistent findings on the role of fish oil in type 2 diabetes mellitus (T2DM). We systematically summarized the available evidence from randomized controlled trials (RCT) and aimed to investigate the effects of fish oil supplementation on glucose control and lipid levels among patients with T2DM. METHODS: A comprehensive literature search was performed in electronic databases (PubMed, ProQuest, Cochrane Library, CNKI, VIP, and Wanfang) to identify all relevant RCTs which were published up to May 31st, 2019. We used Modified Jadad Score system to evaluate the quality of each included RCT. The pooled effects were estimated using random-effects model and presented as standardized mean differences with 95% confidence intervals. RESULTS: A total of 12 RCTs were included in this meta-analysis. There was no significant difference in glucose control outcomes comparing fish oil supplementation to placebo. The effect size of fasting plasma glucose (FPG) was 0.13 (95% CI: - 0.03 to 0.28, p > 0.05). No marked change was observed in fasting insulin (FINS), glycosylated hemoglobin (HbA1c), and HOMA of insulin resistance (HOMA-IR) levels. Fish oil supplementation was associated with a decrease of triglyceride (TG) level by - 0.40 (95%CI: - 0.53 to - 0.28, p < 0.05), and an increase of high density lipoprotein (HDL) cholesterol level by 0.21 (95%CI: 0.05 to 0.37, p < 0.05). In subgroup analysis, HDL cholesterol level was higher among Asian and low-dose(< 2 g/d n-3 PUFA) subgroups compared to their counterparts (p < 0.05). TG level was lower in mid and long duration groups, along with an inconspicuous difference in short duration group. CONCLUSIONS: This meta-analysis shows that among patients with T2DM, fish oil supplementation leads to a favorable blood lipids profile but does not improve glucose control.

Procyanidins Extracted from Lotus Seedpod Ameliorate Amyloid-ß-Induced Toxicity in Rat Pheochromocytoma Cells.

Alzheimer's disease (AD) is a progressive neurodegenerative disease, which is characterized by extracellular senile plaque deposits, intracellular neurofibrillary tangles, and neuronal apoptosis. Amyloid-ß (Aß) plays a critical role in AD that may cause oxidative stress and downregulation of CREB/BDNF signaling. Anti-Aß effect has been discussed as a potential therapeutic strategy for AD. This study aimed to identify the amelioration of procyanidins extracted from lotus seedpod (LSPC) on Aß-induced damage with associated pathways for AD treatment. Rat pheochromocytoma (PC12) cells incubated with Aß 25-35 serve as an Aß damage model to evaluate the effect of LSPC in vitro. Our findings illustrated that LSPC maintained the cellular morphology from deformation and reduced apoptosis rates of cells induced by Aß 25-35. The mechanisms of LSPC to protect cells from Aß-induced damage were based on its regulation of oxidation index and activation of CREB/BDNF signaling, including brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP-responsive element-binding (CREB), protein kinase B (also known as AKT), and the extracellular signal-regulated kinase (ERK). Of note, by high-performance liquid chromatography-tandem mass spectroscopy (LC-MS/MS), several metabolites were detected to accumulate in vivo, part of which could take primary responsibility for the amelioration of Aß-induced damage on PC12 cells. Taken together, our research elucidated the effect of LSPC on neuroprotection through anti-Aß, indicating it as a potential pretreatment for Alzheimer's disease.

Flaxseed Oil Attenuates Hepatic Steatosis and Insulin Resistance in Mice by Rescuing the Adaption to ER Stress.

Increasing evidence has demonstrated the benefits of α-linolenic acid-rich flaxseed oil (ALA-FO) against lipid metabolism abnormality in both rodent models and humans. However, the metabolic response of FO to insulin resistance and type 2 diabetes is still inconsistent. This study aimed to explore the effect of FO on chronic high fat diet (HFD)-induced hepatic steatosis, insulin resistance, and inflammation, mainly focusing on hepatic n-3 fatty acid remodeling and endoplasmic reticulum (ER) unfolded protein response. The results showed that lard-based HFD feeding for 16 weeks (60% fat-derived calories) induced whole-body insulin resistance, lipid profile abnormality, and inflammation in mice, which was alleviated by FO in a dose-dependent manner. Moreover, FO effectively improved hepatic steatosis and insulin resistance in mice by modulating the specific location of ALA and its long-chain n-3 fatty acids across hepatic lipid fractions and enhancing insulin-stimulated phosphorylation of hepatic insulin receptor subtract-1 (IRS-1) tyrosine 632 and protein kinase B (AKT) ( p < 0.05). Importantly, the differential depositions of ALA and its long-chain n-3 fatty acids in plasma and ER membranes were observed, concomitant with the rescued ER unfolded protein response and Jun N-terminal kinase (JNK) signaling in mice liver.

Procyanidins extracted from the litchi pericarp attenuate atherosclerosis and hyperlipidemia associated with consumption of a high fat diet in apolipoprotein-E knockout mice.

The beneficial effects of red wine against cardiovascular disease are associated with the abundant antioxidant polyphenols such as procyanidins. Recently, procyanidins extracted from the litchi pericarp (LPPC), a new source of procyanidins showed strong antioxidant activities in vitro, have been isolated and identified in our laboratory. The aim of present study was to investigate the anti-atherosclerotic effects of LPPC on atherosclerosis and hyperlipidemia in apolipoprotein E knockout (ApoE KO) mice fed a high fat diet (HFD, 21% fat, 0.15% cholesterol) for 24 weeks. The results showed that LPPC intervention alleviated atherosclerosis, fat accumulation and hyperlipidemia in ApoE KO mice. Furthermore, real-time RT-PCR results showed that LPPC can regulate several key genes involved in hepatic lipid homeostasis, such as increasing mRNA levels of farnesoid X receptor (FXR) and small heterodimer partner (SHP) which emerge as key regulators of lipid homeostasis at the transcriptional level, decreasing mRNA levels of 3-hydroxy-3-Methylglutaryl (HMG)-CoA reductase which mediates cholestrol biosynthesis, and up-regulating the mRNA expressions of ATP-binding cassette transporter-1 (ABCA1) which modulates cholesterol efflux. Thus, these results elucidated that LPPC could alleviate the lipid disorder especially hypercholesteromia and ameliorate atherosclerosis in ApoE-KO mice fed a WTD via regulating gene expression involved in hepatic lipid homeostasis effectively.

Flaxseed Oil Alleviates Chronic HFD-Induced Insulin Resistance through Remodeling Lipid Homeostasis in Obese Adipose Tissue.

Emerging evidence suggests that higher circulating long-chain n-3 polyunsaturated fatty acids (n-3PUFA) levels were intimately associated with lower prevalence of obesity and insulin resistance. However, the understanding of bioactivity and potential mechanism of α-linolenic acid-rich flaxseed oil (ALA-FO) against insulin resistance was still limited. This study evaluated the effect of FO on high-fat diet (HFD)-induced insulin resistance in C57BL/6J mice focused on adipose tissue lipolysis. Mice after HFD feeding for 16 weeks (60% fat-derived calories) exhibited systemic insulin resistance, which was greatly attenuated by medium dose of FO (M-FO), paralleling with differential accumulation of ALA and its n-3 derivatives across serum lipid fractions. Moreover, M-FO was sufficient to effectively block the metabolic activation of adipose tissue macrophages (ATMs), thereby improving adipose tissue insulin signaling. Importantly, suppression of hypoxia-inducible factors HIF-1α and HIF-2α were involved in FO-mediated modulation of adipose tissue lipolysis, accompanied by specific reconstitution of n-3PUFA within adipose tissue lipid fractions.

Procyanidins extracted from the litchi pericarp ameliorate atherosclerosis in ApoE knockout mice: their effects on nitric oxide bioavailability and oxidative stress.

Epidemiological studies strongly support the role of procyanidin-rich beverages and fruit in the prevention of cardiovascular diseases. Procyanidins extracted from the litchi pericarp (LPPC), a new source of procyanidins, were isolated and identified in our laboratory and have been proven to possess strong antioxidant activity in vitro. In the present study, we investigated the anti-atherosclerotic effects of LPPC in apolipoprotein E knockout (ApoE KO) mice fed a high fat diet for 24 weeks. LPPC (100 mg kg-1 body mass daily) significantly reduced the atherosclerotic lesion size (P < 0.01 versus ApoE KO mice), excess NO production and iNOS expression. Moreover, the mRNA and protein expressions of eNOS in the aortas of ApoE KO mice were increased by LPPC which further explains the endothelial protective action of LPPC. LPPC also showed profound antioxidant effects in ApoE KO mice. Plasma TBARS contents and the mRNA expression for NADPH oxidase (p47phox, p67phox, NOX-2/gp91phox and NOX-4) in the aortas of ApoE KO mice were significantly reduced, whereas plasma SOD activity was markedly elevated by LPPC. These results elucidated that LPPC could ameliorate atherosclerosis in ApoE-KO mice by improving NO bioavailability and reducing oxidative stress through NADPH oxidase-dependent mechanisms.

Current and prospective sights in mechanism of deoxynivalenol-induced emesis for future scientific study and clinical treatment.

Deoxynivalenol (DON), one of trichothecene mycotoxins produced by the fungus Fusarium, is commonly detected in cereal foods and in secondary food production across the world. Lower concentrations of DON induce a dose-related feed refusal (anorexia), whereas it acts as a potent emetic agent at higher levels. DON-induced emesis in humans and livestock can be observed and recorded in both undeveloped and developed regions such as Lixian, Guide and Huangzhong in China and Illinois in the USA. Some studies with different animal models (pigs and minks) suggested that DON could change expressions of 5-hydroxytryptamine, peptide YY, neuropeptide Y2 receptor and nucleobindin-2/nesfatin-1 in plasma and different areas of the brain. Some selective antagonist of 5-hydroxytryptamine 3 receptors can inhibit DON-induced emetic response. Otherwise, the Ca2+ homeostasis and MAPK pathway could be potential directions in future studies. Dolasetron, dantrolene and JNJ-31020028 can be used in clinical treatment but they have potential toxic effects. (-)Epicatechin, ginger phytochemicals and isoflavone can be tested in in vitro and in vivo for their usage as food additives for reducing the emesis. The present review summarizes and discusses some information from previous and recent prominent publications with the aim to provide some comprehensive and helpful data for understanding the mechanism of DON-induced emesis. Copyright © 2017 John Wiley & Sons, Ltd.

Iron-Mediated Lysosomal Membrane Permeabilization in Ethanol-Induced Hepatic Oxidative Damage and Apoptosis: Protective Effects of Quercetin.

Iron, in its free ferrous states, can catalyze Fenton reaction to produce OH∙, which is recognized as a crucial role in the pathogenesis of alcoholic liver diseases (ALD). As a result of continuous decomposition of iron-containing compounds, lysosomes contain a pool of redox-active iron. To investigate the important role of intralysosomal iron in alcoholic liver injury and the potential protection of quercetin, male C57BL/6J mice fed by Lieber De Carli diets containing ethanol (30% of total calories) were cotreated by quercetin or deferoxamine (DFO) for 15 weeks and ethanol-incubated mice primary hepatocytes were pretreated with FeCl3, DFO, and bafilomycin A1 at their optimal concentrations and exposure times. Chronic ethanol consumption caused an evident increase in lysosomal redox-active iron accompanying sustained oxidative damage. Iron-mediated ROS could trigger lysosomal membrane permeabilization (LMP) and subsequent mitochondria apoptosis. The hepatotoxicity was attenuated by reducing lysosomal iron while being exacerbated by escalating lysosomal iron. Quercetin substantially alleviated the alcoholic liver oxidative damage and apoptosis by decreasing lysosome iron and ameliorating iron-mediated LMP, which provided a new prospective of the use of quercetin against ALD.

Long-Term Dietary Alpha-Linolenic Acid Supplement Alleviates Cognitive Impairment Correlate with Activating Hippocampal CREB Signaling in Natural Aging Rats.

Alpha-linolenic acid (ALA) is a major precursor of the essential n-3 polyunsaturated fatty acid (PUFA), whose deficiency alters the structure and function of membranes and induces cerebral dysfunctions. The major purpose of this study was to investigate the protective effect of prolonged ALA intake on cognitive function during natural aging. Female Sprague-Dawley rats aged 6 months were chronically treated with ALA and/or lard per day for 12 months. Regular diet-treated rats, both young and old (4 and 18 months old, respectively) served as controls. Rats fed on regular diet during aging showed memory deficits in Morris water maze, which were further exacerbated by lard intake. However, supplementation with ALA for 12 months dose-dependently improved the performance in spatial working memory tasks. Memory performance correlated well with the activation of cAMP response element-binding protein (CREB) and increases in both levels of brain-derived neurotrophic factor (BDNF) and its specific receptor tyrosine kinase B (TrkB) phosphorylation in the hippocampus. Further study identified that hippocampal extracellular signal-related kinase (ERK) and Akt rather than calcium calmodulin kinase IV (CaMKIV) and protein kinase A (PKA), the upstream signalings of CREB, were also activated by ALA supplement. Moreover, memory improvement was accompanied with alterations of hippocampal synaptic structure and number, suggestive of enhancement in synaptic plasticity. Together, these results suggest that long-term dietary intake of ALA enhances CREB/BDNF/TrkB pathway through the activation of ERK and Akt signalings in hippocampus, which contributes to its ameliorative effects on cognitive deficits in natural aging.

Chronic alpha-linolenic acid treatment alleviates age-associated neuropathology: Roles of PERK/eIF2α signaling pathway.

Aging is a principal risk factor for neurodegenerative diseases and especially shares similar pathologic mechanisms to Alzheimer's disease (AD). Amyloid-ß (Aß) plaques deposition and neurofibrillary tangles (NFTs) are the prominent age-dependent pathologies implicated in the cognitive deficits. Accumulation of mis-folded proteins in the endoplasmic reticulum triggers a cellular stress response called the unfolded protein response (UPR), the activation of which is increased in AD patients. However, the UPR relates to the pathological hallmarks of aging is still elusive. In this study, we report that long-term supplement of α-linolenic acid (ALA), starting before the onset of disease symptoms (6month-old), prevents the age-related memory deficits during natural aging. The amelioration of the memory impairment is associated with a decrease in UPR related markers [glucose regulated protein 78 (GRP78), protein kinase RNA-like endoplasmic reticulum kinase (PERK), eukaryotic Initiation Factor 2α (eIF2α)]. ALA suppressed the PERK/eIF2α signaling, which may be responsible for multifaceted memory-deteriorating and neurodegenerative mechanisms, including inhibition of Aß production by suppressing ß-site APP-cleaving enzyme 1 (BACE1) expression, enhancement of cAMP response element binding protein (CREB) function via down-regulating activating transcription factor 4 (ATF4), and suppression of Tau phosphorylation by inhibiting glycogen synthase kinase 3ß (GSK-3ß) pathway. Taken together, our findings provide new insights into the link between ALA and PERK/eIF2α signaling, which could contribute to a better understanding of an ALA-mediated protective effect in aging-associated neuropathology.

Ameliorative effects of lutein on non-alcoholic fatty liver disease in rats.

AIM: To investigate the therapeutic effects of lutein against non-alcoholic fatty liver disease (NAFLD) and the related underlying mechanism. METHODS: After 9 d of acclimation to a constant temperature-controlled room (20 °C-22 °C) under 12 h light/dark cycles, male Sprague-Darley rats were randomly divided into two groups and fed a standard commercial diet (n = 8) or a high-fat diet (HFD) (n = 32) for 10 d. Animals receiving HFD were then randomly divided into 4 groups and administered with 0, 12.5, 25, or 50 mg/kg (body weight) per day of lutein for the next 45 d. At the end of the experiment, the perinephric and abdominal adipose tissues of the rats were isolated and weighed. Additionally, serum and liver lipid metabolic condition parameters were measured, and liver function and insulin resistance state indexes were assessed. Liver samples were collected and stained with hematoxylin eosin and Oil Red O, and the expression of the key factors related to insulin signaling and lipid metabolism in the liver were detected using Western blot and real-time polymerase chain reaction analyses. RESULTS: Our data showed that after being fed a high-fat diet for 10 d, the rats showed a significant gain in body weight, energy efficiency, and serum total cholesterol (TC) and triglyceride (TG) levels. Lutein supplementation induced fat loss in rats fed a high-fat diet, without influencing body weight or energy efficiency, and decreased serum TC and hepatic TC and TG levels. Moreover, lutein supplementation decreased hepatic levels of lipid accumulation and glutamic pyruvic transaminase content, and also improved insulin sensitivity. Lutein administration also increased the expression of key factors in hepatic insulin signaling, such as insulin receptor substrate-2, phosphatidylinositol 3-kinase, and glucose transporter-2 at the gene and protein levels. Furthermore, high-dose lutein increased the expression of peroxisome proliferators activated receptor-α and sirtuin 1, which are associated with lipid metabolism and insulin signaling. CONCLUSION: These results demonstrate that lutein has positive effects on NAFLD via the modulation of hepatic lipid accumulation and insulin resistance.