Niacin supplementation attenuates the regression of three-dimensional capillary architecture in unloaded female rat skeletal muscle.

Inactivity can lead to muscle atrophy and capillary regression in skeletal muscle. Niacin (NA), known for inducing hypermetabolism, may help prevent this capillary regression. In this study involving adult female Sprague-Dawley rats, the animals were randomly assigned to one of four groups: control (CON), hindlimb unloading (HU), NA, and HU with NA supplementation (HU + NA). For a period of 2 weeks, the rats in the HU and HU + NA groups underwent HU, while those in the NA and HU + NA groups received NA (750 mg/kg) twice daily through oral administration. The results demonstrated that HU lowered capillary number, luminal diameter, and capillary volume, as well as decreased succinate dehydrogenase activity, slow fiber composition, and PGC-1α expression within the soleus muscle. However, NA supplementation prevented these alterations in capillary structure due to unloading by stimulating PGC-1α factors and inhibiting mitochondrial dysfunction. Therefore, NA supplementation could serve as a potential therapeutic approach for preserving the capillary network and mitochondrial metabolism of muscle fibers during periods of inactivity.

Association of dietary niacin intake with the prevalence and incidence of chronic obstructive pulmonary disease.

Evidence regarding the association between dietary niacin intake and chronic obstructive pulmonary disease (COPD) is limited. Our study investigates the relationship between dietary niacin intake and the prevalance and incidence of COPD in the adult population of the United States, using data from the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2018. Data on niacin intake were extracted through dietary intake interviews. COPD diagnoses were based on lung function, medical history, and medication usage. We analyzed the association between niacin consumption and COPD using multiple logistic regression and restricted cubic spline models. The study included 7055 adult participants, divided into COPD (n = 243; 3.44%) and non-COPD (n = 6812; 96.56%) groups. Those with COPD had lower average niacin intake (21.39 ± 0.62 mg/day) compared to the non-COPD group (25.29 ± 0.23 mg/day, p < 0.001). In the adjusted multivariable model, the odds ratios (OR) and 95% confidence intervals (CI) for COPD in the highest versus lowest quartile of dietary niacin intake were 0.55 (0.33 to 0.89, P for trend = 0.009). Subgroup analysis, after adjustment for various variables, revealed no significant interaction effects. Dietary niacin intake was inversely associated with COPD prevalence in US adults. Participants with the highest dietary niacin intake demonstrated the lowest odds of COPD. The potential of dietary niacin supplementation as a strategy to mitigate COPD warrants further investigation.

Effects of niacin and omega-3 fatty acids on HDL-apolipoprotein A-I exchange in subjects with metabolic syndrome.

HDL-apolipoprotein A-I exchange (HAE) measures a functional property associated with HDL's ability to mediate reverse cholesterol transport. HAE has been used to examine HDL function in case-control studies but not in studies of therapeutics that alter HDL particle composition. This study investigates whether niacin and omega-3 fatty acids induce measurable changes in HAE using a cohort of fifty-six subjects with metabolic syndrome (MetS) who were previously recruited to a double-blind trial where they were randomized to 16 weeks of treatment with dual placebo, extended-release niacin (ERN, 2g/day), prescription omega-3 ethyl esters (P-OM3, 4g/day), or the combination. HAE was assessed at the beginning and end of the study. Compared to placebo, ERN and P-OM3 alone significantly increased HAE by 15.1% [8.2, 22.0] (P<0.0001) and 11.1% [4.5, 17.7] (P<0.0005), respectively, while in combination they increased HAE by 10.0% [2.5, 15.8] (P = 0.005). When HAE was evaluated per unit mass of apoA-I ERN increased apoA-I specific exchange activity by 20% (2, 41 CI, P = 0.02) and P-OM3 by 28% (9.6, 48 CI, P<0.0006). However the combination had no statistically significant effect, 10% (-9, 31 CI, P = 0.39). With regard to P-OM3 therapy in particular, the HAE assay detected an increase in this property in the absence of a concomitant rise in HDL-C and apoA-I levels, suggesting that the assay can detect functional changes in HDL that occur in the absence of traditional biomarkers.

Cholestatic Drug-Induced Liver Injury in a Patient Taking High-Dose Niacin for Hyperlipidemia.

Niacin, an important component of a balanced diet, is central to lipid metabolism. Occasionally used to treat hyperlipidemia, niacin is widely available without a prescription, making its use often unknown to treating physicians. Severe hepatotoxicity has been reported with niacin use. In the following report, we describe a case of hospitalization for acute decompensated cirrhosis with cholestatic morphology in a patient taking self-initiated large quantities of extended-release niacin. Despite medical management and support, the patient unfortunately expired on day 16 of hospitalization. Given ease of access and unclear long-term benefit in hyperlipidemia, the current case serves to raise awareness of niacin's potential hepatotoxicity through highlighting a severe outcome. Although mode of liver injury remains unknown, the use of extended-release niacin formulations and prolonged high-dose supplementation is associated with enhanced hepatotoxicity. Careful review and counseling of commonly available supplements remains an important task of both hospital and primary care physicians.

Omega-3 supplementation improves depressive symptoms, cognitive function and niacin skin flushing response in adolescent depression: A randomized controlled clinical trial.

BACKGROUND: Depressive disorder in adolescents is a major health problem with inadequate treatment. Omega-3 (ω3) polyunsaturated fatty acids are a promising adjuvant therapy in adult depression. The primary objective of this study was to investigate the efficacy of adjuvant ω3 treatment on depressive symptoms in adolescent depression. Secondarily, we explored the effects of ω3 on cognitive function and memory and niacin skin flushing response (NSFR), as their robust associations with adolescent depression. METHODS: A total of 71 adolescents with depression (aged 13-24; 59.2 % female) were randomly assigned to receive ω3 plus Paxil (n = 34) or Paxil alone (n = 37) for 12 weeks. Primary outcome was depression severity according to scores on Montgomery-Asberg Depression Rating Scale (MADRS). Secondary outcomes were cognitive function and memory, and NSFR. RESULTS: Significant improvements in depressive symptoms over time (p = 0.00027 at week 12) were observed in the ω3 + Paxil group compared with Paxil group. Additionally, in the ω3 + Paxil group, significant improvements in memory over time, and greater cognitive function and NSFR were also observed compared with the Paxil group; the NSFR was negatively correlated with MADRS scores at baseline. LIMITATIONS: The trial was open label; thus, the outcome measures should be viewed as preliminary since inherent bias in outcomes due to the potential of a placebo effect. CONCLUSIONS: Our results demonstrate that adjuvant ω3 treatment is effective for reducing depressive symptoms as well as improving cognitive function, memory and the NSFR; these results suggest ω3 is a promising adjuvant treatment for adolescent depression.

The potential prophylactic and therapeutic impacts of niacin on ischemia/reperfusion injury of testis.

INTRODUCTION: The testicular ischemia-reperfusion (I/R) injury is characterized by the excessive aggregation of un-scavenged reactive oxygen species, leading to the heightened levels of oxidative stress. This phenomenon plays a pivotal role in the pathophysiology of testicular torsion damage. OBJECTIVE: The current study aimed to detect the prophylactic and therapeutic effects of niacin on testicular I/R injury. STUDY DESIGN: Twenty-four healthy adult male Sprague Dawley rats were randomly allocated into three groups as follows: (1) sham group, (2) torsion/detorsion (T/D) group, and (3) treatment group which received 200 mg/kg niacin along with testicular T/D. Torsion/detorsion was induced by 2 h of torsion followed by 10 days of reperfusion period. In the treatment group, niacin was injected 30 min before the reperfusion period intraperitoneally and continued for 10 days by oral gavage. RESULTS: T/D was associated with marked decreases in terms of sperm count, viability, and kinematic parameters versus the sham group (P < 0.05), which niacin significantly reverted the kinematic parameters (P < 0.05). I/R injury caused a significant increase in the number of abnormal epididymal sperms compared to the sham group (P < 0.05). Niacin decreased the epididymal sperm abnormality significantly compared to the T/D group (P < 0.05). Tissue abnormalities in T/D group, such as edema, hyperemia, inflammation, and necrosis were completely visible histopathologically, while the histological changes in the niacin-treated group were better than those in the T/D group. Regarding the pathological parametric evaluations, I/R injury significantly reduced the mean testicular biopsy score (MTBS), germinal epithelial cell thickness (GECT), and mean seminiferous tubular diameter (MSTD), and increased the tubular hypoplasia/atrophy (THA) compared to the sham group (P < 0.05), which niacin treatment significantly improved the MTBS and GECT compared to the T/D group (P < 0.05). T/D significantly increased the oxidative stress index (OSI) and lipid peroxidation (MDA) (P < 0.05). Niacin significantly reduced the OSI and MDA levels compared to the T/D group (P < 0.05). DISCUSSION: The current study found that niacin has preventive/therapeutic effects against the elevation of oxidative stress markers and depletion of antioxidants during I/R injury. Following administration of niacin, a reduction in histologic injury was observed in rats. In our study, we showed the antioxidant properties of niacin and its capacity to protect against I/R damage. CONCLUSION: The findings of the present investigation revealed that niacin, as an antioxidant agent, can suppress the oxidative stress induced by testicular I/R injury, and can be used as a supplementary agent in the treatment of those undergoing testicular torsion surgery.

Association between dietary vitamin intake and mortality in US adults with diabetes: A prospective cohort study.

AIMS: To explore the association of dietary vitamin intake from food and/or supplement with mortality in US adults with diabetes. MATERIALS AND METHODS: This prospective cohort study was conducted on 5418 US adults with diabetes from the National Health and Nutrition Examination Survey 1999-2018. Vitamin intake from food and supplements was estimated via dietary recall. Sufficient intake from food or food + supplement was defined as ≥ estimated average requirement (EAR) and ≤ tolerable upper intake level (UL), insufficient intake, < EAR; and excess intake, > UL. Medium supplementary intake was classified as > median level and ≤75th percentile; low intake, ≤ median level; and high intake, >75th percentile, as reported by supplement users. RESULTS: A total of 1601 deaths occurred among the participants over a median follow-up of 11.0 years. Cox regression analysis of the single-vitamin model demonstrated that sufficient vitamin A and folate intake from food and food + supplement and medium vitamin A and folate intake from supplement; sufficient riboflavin, niacin, and vitamin B6 intake from food and food + supplement; and sufficient thiamin and vitamin E intake from food + supplement were significantly associated with reduced all-cause mortality (all p < 0.05). In the multivitamin model, sufficient vitamin A and folate intake from food and food + supplement, medium vitamin A and folate intake from the supplement, and sufficient niacin intake from food and food + supplement were inversely associated with mortality (all p < 0.05). CONCLUSIONS: Vitamin A and folate intake from food or supplement and niacin intake from food were significantly associated with reduced mortality in US adults with diabetes.

Immunological strip sensor for the rapid determination of niacin in dietary supplements and foods.

Herein, four haptens of niacin (Vitamin B3, VB3) were designed, and after a series of experiments, it was concluded that hapten D had the best immune effect. To avoid false positives in the detection of real samples, a monoclonal antibody (mAb) against VB3 was prepared by a matrix effect-enhanced mAb screening method. The concentration of the inhibition rate reaching 50% (IC50) was 603.41 ng mL-1 and the limit of detection (LOD) using an indirect enzyme-linked immunosorbent assay (ic-ELISA) was 54.89 ng mL-1. A lateral flow immunochromatographic assay (LFIA) based on gold nanoparticles was established to detect the concentration of VB3 in compound vitamin B tablets and infant formulas, with a visual LOD of 5 µg mL-1. Using a handheld reader, the quantitative LOD was calculated to be 0.60 µg mL-1. The contents of the compound vitamin B tablets and infant formulas were also verified by liquid chromatography. Therefore, the LFIA developed in this study can be applied to the specific identification and rapid detection of niacin in nutritional dietary supplements, thus meeting the market's demand for efficient niacin detection methods.

SBA-15- and SBA-16-Functionalized Silicas as New Carriers of Niacinamide.

Amorphous silica as a food additive (E 551) is used in food materials (e.g., sweeteners, dairy products) for its anti-caking properties. The physicochemical properties of SiO2 also make it suitable to serve as a carrier of active substances in functional foods, dietary supplements, and drugs. Deficiency of niacinamide (vitamin B3, niacin) leads to several pathologies in the nervous system and causes one of the nutritional diseases called pellagra. The present study focuses on the use of hybrid ordered mesoporous silicas (SBA-15/SBA-16) functionalized with amino groups introduced through grafting or co-condensation with (N-vinylbenzyl)aminoethylaminopropyltrimethoxysilane (Z-6032) as novel carriers of niacinamide. They combine the characteristics of a relatively stable and chemically inert amorphous silica matrix with well-defined structural/textural parameters and organic functional groups that give specific chemical properties. The highest degree of carrier loading with niacinamide (16 wt.%) was recorded for the unmodified SBA-15. On the other hand, the highest degree of niacinamide release characterizes the functionalized SBA-15 sample (60% after 24 h), indicating that the presence of amino groups affects the release profile of niacinamide from the structure of the mesoporous silica.

Immunomodulatory Effects of Combined Nicotinic Acid and Prednisolone in Adjuvant-induced Arthritis.

BACKGROUND: The combination of two drugs may lead to better results while reducing the need for each medication. OBJECTIVE: This study aimed to explore the synergistic benefits of combination therapy by suboptimal dose of niacin (Nic.) and prednisolone (Pred.) in an experimental model of Rheumatoid arthritis (RA). METHODS: About 50 male Wistar rats (weighing 150 - 160 grams) were randomly divided into five groups of ten, including healthy and RA groups treated with Nic. (80 mg/kg-orally), or Pred. (2 mg/kg-orally), and/or co-administration of Nic. and Pred. (half doses with each one-orally). RA was induced by the injection of complete Freund's adjuvant into the hind paw of each rat. All treatments were initiated on the fifth day following the induction and continued until day 30 post-induction. RESULTS: The combined Nic. and Pred. at half doses promoted a significant regression in the severity of the established RA, which is more pronounced than full doses of either drug alone. Combination therapy promoted a reduction in some hematological and biochemical RA parameters, like neutral red uptake by phagocytic cells, myeloperoxidase, nitric oxide, and C-reactive protein, more profound than each drug alone. Combined treatment caused a greater decrease in IFN-γ expression than other treatments in the area of plantar joints. All treatments were effective in increasing the expression of the IL-10 in the area of plantar joints. Prednisolone was less effective in reducing the expression of the TNF-α in the area of plantar joints than the other group. CONCLUSION: This combination may be a useful approach to controlling RA.

Lipid-lowering therapies for cardiovascular disease prevention and management in primary care: PEER umbrella systematic review of systematic reviews.

OBJECTIVE: To assess the benefits and harms of lipid-lowering therapies used to prevent or manage cardiovascular disease including bile acid sequestrants (BAS), ezetimibe, fibrates, niacin, omega-3 supplements, proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors, and statins. DATA SOURCES: MEDLINE, the Cochrane Database of Systematic Reviews, and a grey literature search. STUDY SELECTION: Systematic reviews of randomized controlled trials published between January 2017 and March 2022 looking at statins, ezetimibe, PCSK9 inhibitors, fibrates, BAS, niacin, and omega-3 supplements for preventing cardiovascular outcomes were selected. Outcomes of interest included major adverse cardiovascular events (MACE), cardiovascular mortality, all-cause mortality, and adverse events. SYNTHESIS: A total of 76 systematic reviews were included. Four randomized controlled trials were also included for BAS because no efficacy systematic review was identified. Statins significantly reduced MACE (6 systematic reviews; median risk ratio [RR]=0.74; interquartile range [IQR]=0.71 to 0.76), cardiovascular mortality (7 systematic reviews; median RR=0.85, IQR=0.83 to 0.86), and all-cause mortality (8 systematic reviews; median RR=0.91, IQR=0.88 to 0.92). Major adverse cardiovascular events were also significantly reduced by ezetimibe (3 systematic reviews; median RR=0.93, IQR=0.93 to 0.94), PCSK9 inhibitors (14 systematic reviews; median RR=0.84, IQR=0.83 to 0.87), and fibrates (2 systematic reviews; mean RR=0.86), but these interventions had no effect on cardiovascular or all-cause mortality. Fibrates had no effect on any cardiovascular outcomes when added to a statin. Omega-3 combination supplements had no effect on MACE or all-cause mortality but significantly reduced cardiovascular mortality (5 systematic reviews; median RR=0.93, IQR=0.93 to 0.94). Eicosapentaenoic acid ethyl ester alone significantly reduced MACE (1 systematic review, RR=0.78) and cardiovascular mortality (2 systematic reviews; RRs of 0.82 and 0.82). In primary cardiovascular prevention, only statins showed consistent benefits on MACE (6 systematic reviews; median RR=0.75, IQR=0.73 to 0.78), cardiovascularall-cause mortality (7 systematic reviews, median RR=0.83, IQR=0.81 to 0.90), and all-cause mortality (8 systematic reviews; median RR=0.91, IQR=0.87 to 0.91). CONCLUSION: Statins have the most consistent evidence for the prevention of cardiovascular complications with a relative risk reduction of about 25% for MACE and 10% to 15% for mortality. The addition of ezetimibe, a PCSK9 inhibitor, or eicosapentaenoic acid ethyl ester to a statin provides additional MACE risk reduction but has no effect on all-cause mortality.

Effects of niacin supplementation during in vitro culture on the developmental competence of porcine embryos.

Niacin is a water-soluble vitamin belonging to the vitamin B complex. It has been found to possess various biological activities, including antioxidant and lipid modification capacities. This study aimed to elucidate the effects of niacin treatment in porcine in vitro culture (IVC) medium on embryo developmental competence after parthenogenetic activation. IVC medium was supplemented with different concentrations of niacin (0 [control], 300, 600 and 900 µM). The results showed that embryos cultured in an IVC medium supplemented with 300 and 600 µM niacin had an increased cleavage rate (p < .05). In addition, 300 µM niacin treatment resulted in a higher blastocyst formation rate than the control and other niacin-treated groups. However, the total cell number did not differ significantly among the experimental groups. Niacin supplementation at 600 µM decreased reactive oxygen species, whereas treatment with 300, 600 and 900 µM increased glutathione levels in day two embryos. On day seven, 300 µM niacin exhibited improved fatty acid levels and fewer lipid droplets than the control group. Furthermore, gene expression at the mRNA level was performed on day two and day seven embryos, treated with or without 300 µM niacin. The expression of anti-apoptotic BCL2 and lipid metabolism PLIN2-related genes were upregulated, whereas the pro-apoptotic BAX and CASPASE3 were downregulated with niacin supplementation compared with the control group. However, SIRT1, a gene related to energy and the oxidative state, was up-regulated in niacin-treated day two embryos (p < .05). Overall, the results indicate that niacin has a beneficial effect on pre-implantation embryo development by modulating lipid metabolism and reducing oxidative stress and apoptosis. The expression patterns of PLIN2 and SIRT1 reported here suggest that these transcripts may be involved in the mechanism by which niacin affects the developmental capacity of IVC embryos.

Increased Dietary Niacin Intake Improves Muscle Strength, Quality, and Glucose Homeostasis in Adults over 40 Years of Age.

BACKGROUND AND AIMS: Age-related loss of skeletal muscle mass and strength begins at 40 years of age, and limited evidence suggests that niacin supplementation increases levels of nicotinamide adenine dinucleotide in mouse muscle tissue. In addition, skeletal muscle has a key role in the body's processing of glucose. Therefore, this study aimed to investigate the relationship between dietary niacin and skeletal muscle mass, strength, and glucose homeostasis in people aged 40 years and older. METHODS: This study was an American population-based cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES). Considering that some outcomes are only measured in specific survey cycles and subsamples, we established three data sets: a grip strength dataset (2011-2014, n=3772), a body mass components dataset (2011-2018, n=3279), and a glucose homeostasis dataset (1999-2018, n=9189). Dietary niacin and covariates were measured in all survey cycles. Linear regression or logistic regression models that adjusted for several main covariates, such as physical activity and diet, was used to evaluate the relationship between dietary niacin and grip strength, total lean mass, appendicular lean mass, total fat, trunk fat, total bone mineral content, homeostasis model assessment of insulin resistance (HOMA-IR), fasting blood glycose, fasting insulin and sarcopenia risk. Subgroup analyses, a trend test, an interaction test, and a restricted cubic spline were used for further exploration. RESULTS: Higher dietary niacin intake was significantly correlated with higher grip strength (ß 0.275, 95% confidence intervals [CI] 0.192-0.357), higher total lean mass (ß 0.060, 95% CI 0.045-0.074), higher appendicular lean mass (ß 0.025, 95% CI 0.018-0.033), and higher total bone mineral content (ß 0.005, 95% CI 0.004-0.007). By contrast, higher dietary niacin intake was significantly associated with lower total fat (ß -0.061, 95% CI -0.076 to -0.046), lower trunk fat (ß -0.041, 95% CI -0.050 to -0.032) and lower sarcopenia risk (OR 0.460, 95% CI 0.233 to 0.907). In addition, dietary niacin significantly reduced HOMA-IR, fasting blood glucose (in participants without diabetes), and fasting insulin (p <0.05). CONCLUSION: Niacin is associated with improved body composition (characterized by increased muscle mass and decreased fat content) and improved glucose homeostasis in dietary doses. Dietary niacin supplementation is a feasible way to alleviate age-related muscular loss.

Association of niacin intake with constipation in adult: result from the National Health and Nutrition Examination.

BACKGROUND: Although dietary intake is believed to be associated with constipation, there is currently a lack of research exploring the relationship between niacin intake and constipation. Therefore, the aim of this study is to investigate the association between niacin intake in adults and constipation using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: This study included 5170 participants (aged ≥ 20 years) from the NHANES survey conducted between 2009 and 2010. Participants who reported experiencing constipation "always", "most of the time", or "sometimes" in the past 12 months were defined as constipation cases. The daily niacin intake was obtained from dietary recall and dietary supplement recalls of the patients. Weighted multivariate logistic regression analysis, restricted cubic spline regression, subgroup analysis, and interaction analysis were used to assess the correlation between niacin intake and constipation. RESULTS: After adjustment for covariates, the multivariate logistic regression model showed that low niacin intake was associated with a higher risk of constipation (Model 1: OR: 0.917, 95% CI 0.854-0.985, P = 0.023; Model 2: OR: 0.871, 95% CI 0.794-0.955, P = 0.01). After dividing niacin intake into four groups, a daily intake of 0-18 mg niacin was associated with a higher risk of constipation (Model 1: OR: 1.059, 95% CI 1.012-1.106, P = 0.019; Model 2: OR: 1.073, 95% CI 1.025-1.123, P = 0.013). The restricted cubic spline regression analysis also showed a non-linear relationship between niacin intake and the risk of constipation. CONCLUSION: The findings of this study suggested that daily intake of 0-18 mg of niacin was associated with a higher risk of constipation compared to a daily intake of 18-27 mg of niacin.

Dietary micronutrient adequacies and adherence to the Mediterranean diet in a population of older adults with type 2 diabetes: A cross-sectional study.

BACKGROUND AND AIMS: There are few data on micronutrient intake in older adults with type 2 diabetes (T2D) and their adherence to the Mediterranean diet, a dietary pattern rich in micronutrients. In this cross-sectional study, we evaluated the prevalence of adequacy in micronutrient intake according to the recommendations, and the adherence to the Mediterranean diet in older adults with T2D. METHODS: One hundred thirty-eight patients (47 women and 91 men) with T2D aged over 65 years were included. Dietary habits were assessed by three 24-h dietary recalls. The micronutrient intake, expressed as mean daily intake, and adequacy were compared with the dietary recommendations proposed by the Italian Society of Human Nutrition (LARN) and the European Food Safety Agency (EFSA). Adherence to the Mediterranean diet was evaluated by the MEDI-quest score. RESULTS: An extremely low proportion of participants (∼1%) adhered to the recommendations for potassium and vitamin D intake. A low proportion of participants adhered to the recommendations for calcium (∼23%), magnesium (∼16%), selenium (∼17%), vitamin E (∼14%), riboflavin (∼28%), vitamin B6 (∼29%), folate (∼25%), and niacin (∼27%) intake. More than 60% of the population adhered to the recommendations for iron, copper, vitamin A and B12 intake. Only 53% of the population showed high adherence to the Mediterranean diet. CONCLUSIONS: Our data indicate that a very low proportion of older adults with T2D meet the recommendations for ten micronutrients (calcium, potassium, magnesium, selenium, vitamin D, vitamin E, riboflavin, vitamin B6, folate, and niacin) with an unsatisfactory adherence to the Mediterranean diet. Nutritional approaches aimed at favoring adherence to dietary recommendations and increasing the consumption of foods rich in micronutrients should be implemented in older adults.

Immediate-release niacin and a monounsaturated fatty acid-rich meal on postprandial inflammation and monocyte characteristics in men with metabolic syndrome.

BACKGROUND & AIM: When considered separately, long-term immediate-release niacin and fatty meals enriched in monounsaturated fatty acids (MUFA) decrease postprandial triglycerides, but their effects on postprandial inflammation, which is common in individuals with metabolic syndrome, are less known. Moreover, successful combination is lacking and its impact on acute disorders of the innate immune cells in the metabolic syndrome remains unclear. Here, we aimed to establish the effects from combination with niacin of different fats [butter, enriched in saturated fatty acids (SFA), olive oil, enriched in MUFA, and olive oil supplemented with eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids] on plasma inflammatory markers and circulating monocyte subsets, activation and priming at the postprandial period in individuals with metabolic syndrome. METHODS: A random-order within-subject crossover experiment was performed, in which 16 individuals with metabolic syndrome and 16 age-matched healthy volunteers took 2 g immediate-release niacin together with the corresponding fatty meal or a meal with no fat as control. In total, 128 postprandial curves were analysed. We sampled hourly over 6 h for plasma concentrations of soluble inflammatory markers and triglycerides. Circulating monocyte subsets (CD14/CD16 balance), activation (CCL2/CCR2 axis) and priming (M1/M2-like phenotype) at the time of postprandial hypertriglyceridemic peak were also addressed. RESULTS: Dietary SFA (combined with niacin) promote postprandial excursions of circulating IL-6, IL-1ß, TNF-α and CD14/CCR2-rich monocytes with a pro-inflammatory M1-like phenotype, particularly in individuals with metabolic syndrome. In contrast, dietary MUFA (combined with niacin) postprandially increased circulating CD16-rich monocytes with an anti-inflammatory M2-like phenotype. Omega-3 PUFA did not add to the effects of MUFA. CONCLUSION: The co-administration of a single-dose of immediate-release niacin with a fatty meal rich in MUFA, in contrast to SFA, suppresses postprandial inflammation at the levels of both secretory profile and monocyte response in individuals with metabolic syndrome. These findings highlight a potential role of combining niacin and dietary MUFA for the homeostatic control of inflammation and the innate immune system, identifying a new search direction for the management of disorders associated with the metabolic syndrome.

Role of Vitamins in Cardiovascular Health: Know Your Facts - Part 1.

Cardiovascular (CV) disease (CVD) is a major cause of morbidity and mortality world-wide, thus it is important to adopt preventive interventions. Observational data demonstrating CV benefits of vitamin supplements, advanced by self-proclaimed experts have resulted in ~50% of Americans reporting the use of multivitamins for health promotion; this practice has led to a multi-billion-dollar business of the multivitamin-industry. However, the data on the extensive use of multivitamins show no consistent benefit for CVD prevention or all-cause mortality, while the use of certain vitamins might prove harmful. Thus, the focus of this two-part review is on the attributes or concerns about specific vitamins on CVD. In Part 1, the CV effects of specific vitamins are discussed, indicating the need for further supportive evidence of potential benefits. Vitamin A preserves CV homeostasis as it participates in many biologic functions, including atherosclerosis. However, supplementation could potentially be harmful. Betacarotene, a pro-vitamin A, conveys pro-oxidant actions that may mitigate any other benefits. Folic acid alone and certain B-vitamins (e.g., B1/B2/B6/B12) may reduce CVD, heart failure, and/or stroke, while niacin might increase mortality. Vitamin C has antioxidant and cardioprotective effects. Vitamin D may confer CV protection, but all the data are not in agreement. Combined vitamin E and C have antiatherogenic effects but clinical evidence is inconsistent. Vitamin K seems neutral. Thus, there are individual vitamin actions with favorable CV impact (certain B-vitamins and vitamins C and D), but other vitamins (ß-carotene, niacin) may potentially have deleterious effects, which also holds true for high doses of fat-soluble vitamins (A/D/E/K).

Nicotinic acid attenuates experimental non-alcoholic steatohepatitis by inhibiting the NLRP3 inflammasome/pyroptosis pathway.

Non-alcoholic steatohepatitis (NASH) is a global public health concern that may progress into fibrosis, cirrhosis, and liver cancer, with limited curative treatment options. While the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is closely linked to NASH progression, nicotinic acid (NA), a vitamin used for the treatment of dyslipidemia, is an emerging pharmaceutical treatment for hepatic steatosis and fibrosis. Here, we investigated pharmacological effects of NA on experimental NASH and whether NLRP3 inflammasome/pyroptosis inhibition is an associated mechanism of action. Rats were fed a high-fat sucrose diet supplemented with cholesterol and a low dose of CCl4. NA significantly reduced inflammation by decreasing the protein levels of tumor necrosis factor-alpha and nuclear factor kappa B. Moreover, NA inhibited the formation of NLRP3- apoptosis-associated speck-like protein containing caspase recruitment domain-Caspase-1, decreasing interleukin-1beta, interleukin-18, and gasdermin D protein. In addition, NA reduced tumor growth factor-beta, alpha-smooth muscle actin, and hepatic levels of collagen-1, consequently decreasing extracellular matrix synthesis. Our results indicate that NA can inhibit NASH progression and encourage further basic and clinical studies on the use of NA for the treatment of human NASH.

Hepatic transcript profiling in beef cattle: Effects of rumen-protected niacin supplementation.

The objective of our study was to assess the effect of rumen-protected niacin supplementation on the transcriptome of liver tissue in growing Angus × Simmental steers and heifers through RNA-seq analysis. Consequently, we wanted to assess the known role of niacin in the physiological processes of vasodilation, detoxification, and immune function in beef hepatic tissue. Normal weaned calves (~8 months old) were provided either a control diet or a diet supplemented with rumen-protected niacin (6 g/hd/d) for a 30-day period, followed by a liver biopsy. We observed a significant list of changes at the transcriptome level due to rumen-protected niacin supplementation. Several metabolic pathways revealed potential positive effects to the animal's liver metabolism due to administration of rumen-protected niacin; for example, a decrease in lipolysis, apoptosis, inflammatory responses, atherosclerosis, oxidative stress, fibrosis, and vasodilation-related pathways. Therefore, results from our study showed that the liver transcriptional machinery switched several metabolic pathways to a condition that could potentially benefit the health status of animals supplemented with rumen-protected niacin. In conclusion, based on the results of our study, we can suggest the utilization of rumen-protected niacin supplementation as a nutritional strategy could improve the health status of growing beef cattle in different beef production stages, such as backgrounding operations or new arrivals to a feedlot.