Niacin and its metabolites as master regulators of macrophage activation

Effects of rumen-protected niacin on inflammatory response to repeated intramammary lipopolysaccharide challenges

Nutritional strategies that improve an animal's resilience to various challenges may improve animal health and welfare. One such nutrient is niacin which has reduced inflammation in mice, humans, and swine; however, niacin's anti-inflammatory effects have not been investigated in cattle. Our objective was to determine whether rumen-protected niacin (RPN) alters lactating dairy cows' inflammatory response to intramammary lipopolysaccharide (LPS) challenges, whether RPN resulted in any carry-over effects, and whether repeated LPS challenges result in signs of immune tolerance or innate immune training. Twenty healthy, late-lactation Holstein cows (232 ± 65 d in milk; 39 ± 5.8 kg/d of milk) were enrolled in a randomized complete block experiment which lasted 70 d. Cows received 26 g/d of RPN or no top-dress (CON) for the first 42 d of the experiment. During the final milking of d 27 and 55, cows were challenged in their rear-right mammary gland (RR) with 100 µg of LPS suspended in 5 mL of phosphate buffered saline. Milk yield, milk conductivity, and feed intake were measured daily. Milk composition was measured on d 14, 23, 24, 30, 37, 45, and 52. Blood samples were collected at 0, 8, 12, 24, 48, 72, 96, and 120 h after each LPS challenge, whereas RR quarter milk samples were collected at 0, 8, 16, 24, 48, 72, 96, 120, 144, and 168 h after each LPS challenge. Body temperature was measured continuously during each challenge with an intravaginal thermometer. Linear mixed models with repeated measures were used to analyze the results. Before LPS challenge, RPN did not affect feed intake or milk production, but it reduced SCS (1.24 ± 0.41 vs. 0.05 ± 0.45). After challenge, RPN did not affect feed intake, milk production, milk composition, SCS, body temperature, plasma glucose, or plasma insulin concentrations. Our results suggest RPN reduced peak plasma haptoglobin and lipopolysaccharide binding protein (LBP) during the 1st LPS challenge. Plasma haptoglobin tended to be less after the 2nd challenge for cows previously supplemented RPN while LBP was similar for each treatment group after the 2nd challenge. The 2nd LPS challenge resulted in decreased plasma haptoglobin compared with the 1st LPS challenge, suggestive of tolerance but it also induced a greater peak SCS than the 1st LPS challenge. Our results suggest that repeated LPS challenges promote a systemic tolerance but heightened local response to LPS-induced mastitis. Feeding RPN reduced SCS before challenge and reduced plasma acute phase proteins after challenge suggesting that RPN may reduce systemic inflammation without altering the local inflammatory responses.

The use of omics technologies in creating LBP and postbiotics based on the Limosilactobacillus fermentum U-21

In recent years, there has been an increasing tendency to create drugs based on certain commensal bacteria of the human microbiota and their ingredients, primarily focusing on live biotherapeutics (LBPs) and postbiotics. The creation of such drugs, termed pharmacobiotics, necessitates an understanding of their mechanisms of action and the identification of pharmacologically active ingredients that determine their target properties. Typically, these are complexes of biologically active substances synthesized by specific strains, promoted as LBPs or postbiotics (including vesicles): proteins, enzymes, low molecular weight metabolites, small RNAs, etc. This study employs omics technologies, including genomics, proteomics, and metabolomics, to explore the potential of Limosilactobacillus fermentum U-21 for innovative LBP and postbiotic formulations targeting neuroinflammatory processes. Proteomic techniques identified and quantified proteins expressed by L. fermentum U-21, highlighting their functional attributes and potential applications. Key identified proteins include ATP-dependent Clp protease (ClpL), chaperone protein DnaK, protein GrpE, thioredoxin reductase, LysM peptidoglycan-binding domain-containing protein, and NlpC/P60 domain-containing protein, which have roles in disaggregase, antioxidant, and immunomodulatory activities. Metabolomic analysis provided insights into small-molecule metabolites produced during fermentation, revealing compounds with anti-neuroinflammatory activity. Significant metabolites produced by L. fermentum U-21 include GABA (γ-aminobutyric acid), niacin, aucubin, and scyllo-inositol. GABA was found to stabilize neuronal activity, potentially counteracting neurodegenerative processes. Niacin, essential for optimal nervous system function, was detected in vesicles and culture fluid, and it modulates cytokine production, maintaining immune homeostasis. Aucubin, an iridoid glycoside usually secreted by plants, was identified as having antioxidant properties, addressing issues of bioavailability for therapeutic use. Scyllo-inositol, identified in vesicles, acts as a chemical chaperone, reducing abnormal protein clumps linked to neurodegenerative diseases. These findings demonstrate the capability of L. fermentum U-21 to produce bioactive substances that could be harnessed in the development of pharmacobiotics for neurodegenerative diseases, contributing to their immunomodulatory, anti-neuroinflammatory, and neuromodulatory activities. Data of the HPLC-MS/MS analysis are available via ProteomeXchange with identifier PXD050857.

[Effects of Oxidative Stress on Mitochondrial Functions and Intervertebral Disc Cells]

Intervertebral disc degeneration is widely recognized as one of the main causes of lower back pain. Intervertebral disc cells are the primary cellular components of the discs, responsible for synthesizing and secreting collagen and proteoglycans to maintain the structural and functional stability of the discs. Additionally, intervertebral disc cells are involved in maintaining the nutritional and metabolic balance, as well as exerting antioxidant and anti-inflammatory effects within the intervertebral discs. Consequently, intervertebral disc cells play a crucial role in the process of disc degeneration. When these cells are exposed to oxidative stress, mitochondria can be damaged, which may disrupt normal cellular function and accelerate degenerative changes. Mitochondria serve as the powerhouse of cells, being the primary energy-producing organelles that control a number of vital processes, such as cell death. On the other hand, mitochondrial dysfunction may be associated with various degenerative pathophysiological conditions. Moreover, mitochondria are the key site for oxidation-reduction reactions. Excessive oxidative stress and reactive oxygen species can negatively impact on mitochondrial function, potentially leading to mitochondrial damage and impaired functionality. These factors, in turn, triggers inflammatory responses, mitochondrial DNA damage, and cell apoptosis, playing a significant role in the pathological processes of intervertebral disc cell degeneration. This review is focused on exploring the impact of oxidative stress and reactive oxygen species on mitochondria and the crucial roles played by oxidative stress and reactive oxygen species in the pathological processes of intervertebral disc cells. In addition, we discussed current cutting-edge treatments and introduced the use of mitochondrial antioxidants and protectants as a potential method to slow down oxidative stress in the treatment of disc degeneration.

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.

Association between niacin intake and knee osteoarthritis pain and function: a longitudinal cohort study

BACKGROUND

This research investigates the relationship between niacin intake and knee osteoarthritis (OA) severity, focusing on pain and functional ability due to niacin's role as a NAD(P)+ precursor, promoting cellular energy, and offering anti-inflammatory, analgesic, and antioxidant effects.

METHODS

The population-based Osteoarthritis Initiative (OAI) cohort with radiographically confirmed knee OA was analyzed through a Food Frequency Questionnaire determining niacin intake and scores from the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), using generalized additive mixed models.

RESULTS

A significant correlation was pinpointed in 2375 OA patients (1001 men and 1374 women; 55.96% aged between 45 and 65 and 44.04% aged ≥65) between niacin intake and reduced knee pain and functional degrees after a 48-month follow-up, evident in improved KOOS and WOMAC scores (P < 0.05). The fully adjusted models estimated a decrease of 0.26 points for every additional 1 unit of Ln-niacin intake of daily niacin intake on the WOMAC pain subscale, 0.83 points on the WOMAC function subscale, and an increase of 1.71 and 1.58 on the KOOS pain and quality of life score. Strikingly, subgroups including middle-aged individuals, women, white race, obese individuals, and those with specific dietary habits showed a more substantial improvement with increased niacin.

CONCLUSION

The association between increased niacin intake and reduced pain and function scores, as well improved quality of life in knee OA patients, is significant. Certain cohorts, according to a stratified analysis, could see more considerable benefits with increased niacin consumption.

HIGHLIGHTS

• Increased niacin intake is linked to reduced knee pain and better function in OA patients. • Specific subgroups, such as middle-aged individuals, women, and those with certain dietary habits, benefit more from increased niacin consumption. • Niacin shows promise for enhancing the quality of life in knee OA patients by reducing pain and improving function.

In Vitro Targeted Delivery of Simvastatin and Niacin to Macrophages Using Mannan-Grafted Magnetite Nanoparticles

Atherosclerosis, a leading cause of mortality worldwide, involves various subsets of macrophages that contribute to its initiation and progression. Current treatment approaches focus on systemic, long-term administration of cholesterol-lowering antioxidants such as statins and certain vitamins, which unfortunately come with prolonged side effects. To overcome these drawbacks, a mannose-containing magnetic nanoparticle (NP) is introduced as a drug delivery system to specifically target macrophages in vitro using simvastatin or niacin and a combinational therapy approach that reduces local inflammation while avoiding unwanted side effects. The synthesized NPs exhibited superparamagnetic behavior, neutrally charged thin coating with a hydrodynamic size of 77.23 ± 13.90 nm, and a metallic core ranging from 15 to 25 nm. Efficient loading of niacin (87.21%) and simvastatin (75.36%) on the NPs was achieved at respective weights of 20.13 and 5.03 (w/w). In the presence of a mannan hydrolyzing enzyme, 79.51% of simvastatin and 67.23% of niacin were released from the NPs within 90 min, with a leakage rate below 19.22%. Additionally, the coated NPs showed no destructive effect on J774A macrophages up to a concentration of 200 μg/mL. Simvastatin-loaded NPs exhibited a minimal increase in IL-6 expression. The low dosage of simvastatin decreased both IL-6 and ARG1 expressions, while niacin and combined simvastatin/niacin increased the level of ARG1 expression significantly. Toxicity evaluations on human umbilical vein endothelial cells and murine liver cells revealed that free simvastatin administration caused significant toxicity, whereas the encapsulated forms of simvastatin, niacin, and a combination of simvastatin/niacin at equivalent concentrations exhibited no significant toxicity. Hence, the controlled release of the encapsulated form of simvastatin and niacin resulted in the effective modulation of macrophage polarization. The delivery system showed suitability for targeting macrophages to atherosclerotic plaque.

The impact of three carbapenems at a single-day dose on intestinal colonization resistance against carbapenem-resistant Klebsiella pneumoniae

IMPORTANCE

The intestinal colonization of carbapenem-resistant Klebsiella pneumoniae (CRKP) is an important source of clinical infection. Our research showed that even single-day dose use of carbapenems caused CRKP colonization and continuous bacterial shedding, which reminds clinical doctors to prescribe carbapenems cautiously. Whenever possible, ertapenem should be the preferred choice over other carbapenems especially when the identified or highly suspected pathogens can be effectively targeted by ertapenem.

Management of a Patient With Premenstrual Syndrome Using Acupuncture, Supplements, and Meditation: A Case Report

Objective

The purpose of this case report was to describe a multimodal approach for the treatment of premenstrual syndrome (PMS).

Clinical Features

A 36-year-old nulliparous woman presented to a free clinic for veterans and their spouses. She received a PMS diagnosis at age 18. She was previously prescribed hormonal birth control and nonsteroidal anti-inflammatory drugs, which minimally affected her condition. She stopped using conventional medicine therapies at age 27. Laboratory results showed that her progesterone was below 0.5 ng/mL. Her symptom score was 50 out of 60 on the Treatment Strategies for PMS assessment tool. During her menses, she experienced low back pain and stiffness, bloating, swelling, weight gain, breast tenderness, swelling, and pain, and she felt overwhelmed and stressed.

Intervention and Outcome

Traditional Chinese medicine acupuncture was administered in conjunction with 100 mg of coenzyme Q10 (ubiquinol) and a B-100 complex once a day and 400 mg of magnesium citrate, 1000 mg of flaxseed oil (Linum usitatissimum), and 1000 mg of turmeric (Curcuma longa) twice a day. Five days before the onset of her menstrual period, she was to ingest a B-100 complex twice a day and 400 mg of magnesium citrate, 1000 mg of flaxseed oil, and 1000 mg of turmeric 3 times a day. Mindfulness meditation was encouraged twice a day for 10 minutes to reduce stress. After 12 treatments over 3 months, her symptom score decreased to 18 out of 60 and remained below 20 for an additional 32 weeks.

Conclusion

This patient with PMS symptoms positively responded to a multimodal approach using traditional Chinese medicine-style acupuncture, dietary supplements, and mindfulness meditation.

Association of the Oxidative Balance Score and Cognitive Function and the Mediating Role of Oxidative Stress: Evidence from the National Health and Nutrition Examination Survey (NHANES) 2011-2014

BACKGROUND

Oxidative stress is possibly related to cognitive function decline. The oxidative balance score (OBS) that combines pro- and antioxidant components from diet and lifestyle has been reported to be associated with age-related diseases.

OBJECTIVES

We aimed to investigate the association between OBS and cognitive function in older adults and explore whether oxidative stress mediated this relationship.

METHODS

A total of 1745 adults aged ≥60 y were included in the National Health and Nutrition Examination Survey (NHANES) 2011-2014. Cognitive function was measured using 4 tests: the immediate recall test, delayed recall test, animal fluency test (AFT), and digital symbol substitution test (DSST). Weighted multivariate linear regression and restricted cubic splines (RCS) analyses were used to evaluate the association between OBS and cognitive function, and mediation analysis was used to test the indirect effect of oxidative stress indicators on the association.

RESULTS

The OBS was positively associated with AFT, DSST, and global cognitive function in older adults, and the beta estimates (95% CI) were 0.015 (0.008, 0.034), 0.009 (0.002, 0.025), and 0.030 (0.024, 0.074), moreover, RCS results suggested an approximately linear dose-response relationship between the OBS and these 3 tests. The highest quartiles of these 3 tests were also significantly correlated with OBS. Albumin, uric acid, and serum 25(OH)D concentrations were significant mediators of the relationship between OBS and cognitive function, and the overall mediation effect proportion was 36% when included in 1 model.

CONCLUSIONS

OBS was positively correlated with cognitive function in older adults, and albumin, uric acid, and serum 25(OH)D concentrations could be the driving mediators of the association. The findings emphasize the importance of a healthy, antioxidant diet and lifestyle that contribute to cognitive function. J Nutr 20xx;x:xx.

Hemp Protein Hydrolysates Modulate Inflammasome-Related Genes in Microglial Cells

A prolonged inflammatory response can lead to the development of neurodegenerative diseases such as Alzheimer's disease. Enzymatic hydrolysis is a sustainable way to increase the value of protein sources by obtaining peptides that can exert bioactivity. Hemp (Cannabis sativa L.) protein hydrolysates have been proven to exert anti-inflammatory activity. In this study, two hemp protein hydrolysate (HPHs), obtained with Alcalase as sole catalyst, or with Alcalase followed by Flavourzyme, were evaluated as inflammatory mediators (TNFα, IL-1β, IL-6, and IL-10), microglial polarization markers (Ccr7, iNos, Arg1, and Ym1), and genes related to inflammasome activation (Nlrp3, Asc, Casp1, and Il18), employing the lipopolysaccharide (LPS)-induced neuroinflammation model in murine BV-2 microglial cells. A significant decrease of the expression of proinflammatory genes (e.g., Tnfα, Ccr7, inos, and Nlrp3, among others) and increase of the expression anti-inflammatory cytokines in microglial cells was observed after treatment with the test HPHs. This result in the cell model suggests a polarization toward an anti-inflammatory M2 phenotype. Our results show that the evaluated HPHs show potential neuroprotective activity in microglial cells via the inflammasome.

HClO-triggered interventional probe enabled early detection and intervention of atherosclerosis

Foam cell formation and further accumulation in the subendothelial space of the vascular wall is a hallmark of early atherosclerosis (AS). Targeting foam cell formation can be a promising approach for the early detection and prevention of AS. However, only a few studies have actually examined foam cells in vivo, and most methods combined nanotechnology with angiography, which is complex and could cause further damage to the endothelium. Herein, based on methylene blue, a biosafe NIR dye approved by the FDA, an interventional probe (HMB-NA@Mp) triggered by hypochlorous acid (HClO) was designed for imaging foam cells easily, safely, and effectively in the early stage of AS. Here, encapsulation of the probe by foam cells targeted platelet membrane (Mp) increased probe targeting and reduced toxicity. Cell and animal experimental results showed that the probe could accumulate at the lesion site and significantly enhance fluorescence in the early AS model group. Remarkably, at the same time, it could also release the metabolite niacin, which played a role in inhibiting atherosclerosis. Thus, HMB-NA@Mp is expected to be a powerful means for the early detection and timely intervention of early AS in the absence of clinical symptoms.

Antioxidant and Immunomodulatory Properties of Chia Protein Hydrolysates in Primary Human Monocyte-Macrophage Plasticity

Chia (Salvia hispanica L.) seed has high potential in the development of functional food due to its protein content with a special amino acid profile. Among the hematopoietic-derived cells, monocytes are endowed with high plasticity, responsible for their pro- and anti-inflammatory function in M1 and M2 phenotype polarization, respectively. Indeed, monocytes are involved in several oxidative- and inflammatory-associated disorders such as cancer, obesity, and cardiovascular and neurodegenerative diseases. This study was designed to investigate the role of chia protein hydrolysates (CPHs) in primary human monocyte–macrophage plasticity response using biochemical, RT-qPCR, and ELISA assays. Our results showed that CPHs reduce ROS and nitrite output, as pro-inflammatory cytokine secretion, and enhance the expression and release of anti-inflammatory cytokines. In addition, CPHs reverse LPS-associated M1 polarization into M2. These findings open new opportunities for developing nutritional strategies with chia as a dietary source of biopeptides to prevent the development and progression of oxidative- and inflammatory-related diseases.

Metabonomic identification of serum biomarkers related to heat stress tolerance of sheep

Heat stress is considered as a limiting factor for sheep production; it is necessary to screen for sheep breeds with heat tolerance. This study was to compare the serum metabolomes of Hu sheep and Dorper sheep and identify potential biomarkers related to heat stress. The results revealed that the respiratory rate, heart rate, and rectal temperature of Dorper sheep were significantly higher than those of Hu sheep. Compared to Dorper sheep, the serum activities of total antioxidant capacity and glutathione peroxidase in Hu sheep were significantly higher, while the concentration of malondialdehyde was lower. Metabolomics analysis identified 107 differential serum metabolites. The pathways enriched from the altered serum metabolites between the two breeds were mainly involved in protein metabolism, carbohydrate metabolism, and lipid metabolism. The levels of antioxidant- and energy-related metabolites were higher in the serum of Hu sheep than that of Dorper sheep; however, the levels of lipid catabolism- and inflammation-related were higher in the serum of Dorper sheep. The results indicate that Hu sheep had better heat stress resistance capability than Dorper sheep. Moreover, high levels of metabolites in the serum of Hu sheep are potential biomarkers for heat stress tolerance, including l-methionine, s-adenosylmethionine, and nicotinuric acid.

Metabolite G-Protein Coupled Receptors in Cardio-Metabolic Diseases

G protein-coupled receptors (GPCRs) have originally been described as a family of receptors activated by hormones, neurotransmitters, and other mediators. However, in recent years GPCRs have shown to bind endogenous metabolites, which serve functions other than as signaling mediators. These receptors respond to fatty acids, mono- and disaccharides, amino acids, or various intermediates and products of metabolism, including ketone bodies, lactate, succinate, or bile acids. Given that many of these metabolic processes are dysregulated under pathological conditions, including diabetes, dyslipidemia, and obesity, receptors of endogenous metabolites have also been recognized as potential drug targets to prevent and/or treat metabolic and cardiovascular diseases. This review describes G protein-coupled receptors activated by endogenous metabolites and summarizes their physiological, pathophysiological, and potential pharmacological roles.

What We Know So Far about the Metabolite-Mediated Microbiota-Intestinal Immunity Dialogue and How to Hear the Sound of This Crosstalk

Trillions of microorganisms, termed the "microbiota", reside in the mammalian gastrointestinal tract, and collectively participate in regulating the host phenotype. It is now clear that the gut microbiota, metabolites, and intestinal immune function are correlated, and that alterations of the complex and dynamic host-microbiota interactions can have deep consequences for host health. However, the mechanisms by which the immune system regulates the microbiota and by which the microbiota shapes host immunity are still not fully understood. This article discusses the contribution of metabolites in the crosstalk between gut microbiota and immune cells. The identification of key metabolites having a causal effect on immune responses and of the mechanisms involved can contribute to a deeper insight into host-microorganism relationships. This will allow a better understanding of the correlation between dysbiosis, microbial-based dysmetabolism, and pathogenesis, thus creating opportunities to develop microbiota-based therapeutics to improve human health. In particular, we systematically review the role of soluble and membrane-bound microbial metabolites in modulating host immunity in the gut, and of immune cells-derived metabolites affecting the microbiota, while discussing evidence of the bidirectional impact of this crosstalk. Furthermore, we discuss the potential strategies to hear the sound of such metabolite-mediated crosstalk.

Expanding the drug discovery space with predicted metabolite-target interactions

Metabolites produced in the human gut are known modulators of host immunity. However, large-scale identification of metabolite-host receptor interactions remains a daunting challenge. Here, we employed computational approaches to identify 983 potential metabolite-target interactions using the Inflammatory Bowel Disease (IBD) cohort dataset of the Human Microbiome Project 2 (HMP2). Using a consensus of multiple machine learning methods, we ranked metabolites based on importance to IBD, followed by virtual ligand-based screening to identify possible human targets and adding evidence from compound assay, differential gene expression, pathway enrichment, and genome-wide association studies. We confirmed known metabolite-target pairs such as nicotinic acid-GPR109a or linoleoyl ethanolamide-GPR119 and inferred interactions of interest including oleanolic acid-GABRG2 and alpha-CEHC-THRB. Eleven metabolites were tested for bioactivity in vitro using human primary cell-types. By expanding the universe of possible microbial metabolite-host protein interactions, we provide multiple drug targets for potential immune-therapies.

Nutritional Components in Western Diet Versus Mediterranean Diet at the Gut Microbiota-Immune System Interplay. Implications for Health and Disease

The most prevalent diseases of our time, non-communicable diseases (NCDs) (including obesity, type 2 diabetes, cardiovascular diseases and some types of cancer) are rising worldwide. All of them share the condition of an “inflammatory disorder”, with impaired immune functions frequently caused or accompanied by alterations in gut microbiota. These multifactorial maladies also have in common malnutrition related to physiopathology. In this context, diet is the greatest modulator of immune system–microbiota crosstalk, and much interest, and new challenges, are arising in the area of precision nutrition as a way towards treatment and prevention. It is a fact that the westernized diet (WD) is partly responsible for the increased prevalence of NCDs, negatively affecting both gut microbiota and the immune system. Conversely, other nutritional approaches, such as Mediterranean diet (MD), positively influence immune system and gut microbiota, and is proposed not only as a potential tool in the clinical management of different disease conditions, but also for prevention and health promotion globally. Thus, the purpose of this review is to determine the regulatory role of nutritional components of WD and MD in the gut microbiota and immune system interplay, in order to understand, and create awareness of, the influence of diet over both key components.

M. tuberculosis curli pili (MTP) is associated with alterations in carbon, fatty acid and amino acid metabolism in a THP-1 macrophage infection model

The initial host-pathogen interaction is crucial for the establishment of infection. An improved understanding of the pathophysiology of Mycobacterium tuberculosis (M. tuberculosis) during macrophage infection can aid the development of intervention therapeutics against tuberculosis. M. tuberculosis curli pili (MTP) is a surface located adhesin, involved in the first point-of-contact between pathogen and host. This study aimed to better understand the role of MTP in modulating the intertwined metabolic pathways of M. tuberculosis and its THP-1 macrophage host. Metabolites were extracted from pelleted wet cell mass of THP-1 macrophages infected with M. tuberculosis wild-type V9124 (WT), Δmtp-deletion mutant and the mtp-complemented strains, respectively, via a whole metabolome extraction method using a 1:3:1 ratio of chloroform:methanol:water. Metabolites were detected by two-dimensional gas chromatography time-of-flight mass spectrometry. Significant metabolites were determined through univariate and multivariate statistical tests and online pathway databases. Relative to the WT, a total of nine and ten metabolites were significantly different in the Δmtp and complement strains, respectively. All nine significant metabolites were found in elevated levels in the Δmtp relative to the WT. Additionally, of the ten significant metabolites, eight were detected in lower levels and two were detected in higher levels in the complement relative to the WT. The absence of the MTP adhesin resulted in reduced virulence of M. tuberculosis leading to alterations in metabolites involved in carbon, fatty acid and amino acid metabolism during macrophage infection, suggesting that MTP plays an important role in the modulation of host metabolic activity. These findings support the prominent role of the MTP adhesin as a virulence factor as well as a promising biomarker for possible diagnostic and therapeutic intervention.

Modulatory Effect of Nicotinic Acid on the Metabolism of Caco-2 Cells Exposed to IL-1β and LPS

Inflammatory bowel diseases (IBD) are the most common gastrointestinal inflammatory pathologies. Previous work evidenced a lower content of nicotinic acid (NA) in feces of IBD patients compared to healthy subjects. In the present study, we aimed to understand the effects of NA on intestinal inflammation, as several studies reported its possible beneficial effect, and investigate its influence on inflammation-driven metabolism. NA was tested on a Caco-2 in-vitro model in which inflammation was induced with interleukin-1β (IL-1β) and lipopolysaccharide (LPS), two mayor proinflammatory compounds produced in IBD, that stimulate the production of cytokines, such as interleukin 8. A metabolomics approach, with gas chromatography–mass spectrometry (GC-MS) and nuclear proton magnetic resonance (¹H-NMR), was applied to study the metabolic changes. The results showed that NA significantly reduced the level of IL-8 produced in both LPS and IL-1β stimulated cells, confirming the anti-inflammatory effect of NA also on intestinal inflammation. Moreover, it was demonstrated that NA treatment had a restoring effect on several metabolites whose levels were modified by treatments with IL-1β or LPS. This study points out a possible use of NA as anti-inflammatory compound and might be considered as a promising starting point in understanding the beneficial effect of NA in IBD.

Neuroprotective protein hydrolysates from hemp (Cannabis sativa L.) seeds

Hemp (Cannabis sativa L.) seeds are well known for their potential use as a source of nutrients, fiber, and bioactive compounds. A hemp protein isolate, prepared from defatted hemp flour, was hydrolyzed by alcalase and flavourzyme under specific conditions. The resulting hydrolysates were evaluated for the selection of potentially bioactive hemp protein hydrolysates (HPHs) owing to their DPPH scavenging and ferric reducing antioxidant power activity. In vitro cell-free experiments led to the identification of two bioactive HPHs, HPH20A and HPH60A + 15AF, which were used at 50 and 100 μg mL-1 on BV-2 microglial cells in order to evaluate the anti-neuroinflammatory activities. Our results showed that HPH20A and HPH60A + 15AF down-regulated TNF-α, IL-1β, and IL-6 mRNA transcriptional levels in LPS-stimulated BV-2 microglial cells. In addition, HPH20A and HPH60A + 15AF up-regulated the gene expression of anti-inflammatory cytokine IL-10. This study suggests for the first time that HPHs may improve the neuroinflammatory and inflammatory states, supporting the nutraceutical value of hemp seeds.

Silk based scaffolds with immunomodulatory capacity: anti-inflammatory effects of nicotinic acid

Here we show that 3D silk scaffolds loaded with nicotinic acid have great potential for tissue engineering due to their excellent cytocompatibility and ability to decrease the expression of proinflammatory markers in a concentration dependent manner.

GPETAFLR, an octapeptide isolated from Lupinus angustifolius L. protein hydrolysate, promotes the skewing to the M2 phenotype in human primary monocytes

The present study aimed to test the mechanisms by which GPETAFLR, released from the enzymatic hydrolysis of lupine protein, may modulate the inflammatory response and plasticity in human primary monocytes. Human circulating monocytes and mature macrophages were used to analyze the effects of GPETAFLR on plasticity and inflammatory response using biochemical, flow cytometry, quantitative real-time PCR, and ELISA assays. GPETAFLR skewed the monocyte plasticity towards the anti-inflammatory non-classical CD14+CD16++ monocyte subset and reduced the inflammatory competence of LPS-treated human monocytes diminishing IL-1β, IL-6, and TNF-α and increasing IL-10 production and gene expression. Results showed that GPETAFLR decreased the frequency of the LPS-induced activated monocyte population (CD14++CD16-), diminished monocyte activation involved down-regulation of CCR2 mRNA expression and protein expression, and decreased gene expression of the LPS-induced chemoattractant mediator CCL2. Our findings imply a new understanding of the mechanisms by which GPETAFLR favor a continuous and gradual plasticity process in the human monocyte/macrophage system and offer novel benefits derived from the consumption of Lupinus angustifolius L. in the prevention of inflammatory-related diseases.

Monounsaturated Fatty Acids in a High-Fat Diet and Niacin Protect from White Fat Dysfunction in the Metabolic Syndrome

SCOPE

Obesity is a principal causative factor of metabolic syndrome. Niacin potently regulates lipid metabolism. Replacement of saturated fatty acids by MUFAs or inclusion of omega-3 long-chain PUFAs in the diet improves plasma lipid levels. However, the potential benefits of niacin in combination with MUFAs or omega-3 long-chain PUFAs against white adipose tissue (WAT) dysfunction in the high fat diet (HFD)-induced metabolic syndrome are unknown.

METHODS AND RESULTS

Male Lep^ob/ob LDLR^-/- mice are fed a chow diet or HFDs based on milk cream (21% kcal), olive oil (21% kcal), or olive oil (20% kcal) plus 1% kcal from eicosapentaenoic and docosahexaenoic acids, including immediate-release niacin (1% w/v) in drinking water, for 8 weeks. Mice are then phenotyped. Dietary MUFAs are identified as positive regulators of adipose NAD⁺ signaling pathways by triggering NAD⁺ biosynthesis via the salvage pathway. This coexists with overexpression of genes involved in recognition of NAD⁺ and fatty acids, a surrounding lipid environment dominated by exogenous oleic acid and an alternatively activated macrophage profile, which culminate in a healthy expansion of WAT and improvement of several hallmarks that typify the metabolic syndrome.

CONCLUSION

Niacin in combination with dietary MUFAs can favor WAT homeostasis in the development of HFD-induced obesity and metabolic syndrome.

GPETAFLR, a biopeptide from Lupinus angustifolius L., protects against oxidative and inflammatory damage in retinal pigment epithelium cells

GPETAFLR, an octapeptide released from the enzymatic hydrolysis of lupine (Lupinus angustifolius L.) protein, has demonstrated anti-inflammatory effect in myeloid lineage. This work aims to evaluate in retinal pigment epithelium (RPE) cells the protective role of GPETAFLR on both oxidative and inflammatory markers known to be involved in age-related macular degeneration (AMD). In comparison with stimulated control cells, GPETAFLR increased glutathione production and diminished the secretion and gene expression of VEFG, IL-1β, IL-6, IFNγ, and TNF-α, as well as reactive oxygen species, and nitrite output. Our findings reveal that GPETAFLR, a novel plant peptide, is able to protect against RPE oxidative stress and inflammation. Taken together, these results strongly support innovative nutritional strategies considering Lupinus angustifolius L. as source of proteins to prevent the onset and progression of AMD. PRACTICAL APPLICATIONS: We reveal a novel nutraceutical impact of GPETAFLR peptide in human RPE cells to prevent oxidative and inflammatory mediators. Our results support that the intake of Lupine angustifolius L., proposed to be a reservoir of GPETAFLR, could lessen the functional decay of RPE cells, leading therefore to a slowdown of the progress of AMD during age. Not only this work, but also future simple clinical studies should raise new nutritional strategies focused on understanding the etiological role of the foods, nutrition, and metabolism in the pathogenesis of ocular disorders.

Nicotinic acid suppresses sebaceous lipogenesis of human sebocytes via activating hydroxycarboxylic acid receptor 2 (HCA2 )

Nicotinic acid (NA) activates hydroxycarboxylic acid receptor 2 (HCA₂), and it is widely used in treating dyslipidaemias. Since its side effects include skin dryness, whereas its deficiency can be accompanied by dyssebacia, characterized by sebaceous gland enlargement, we asked if HCA₂ is expressed on human sebocytes, and if NA influences sebocyte functions. By using human immortalized SZ95 sebocytes, we found that non‐cytotoxic (≤100 μmol/L; MTT‐assay) concentrations of NA had no effect on the homeostatic sebaceous lipogenesis (SLG; Nile Red), but normalized excessive, acne‐mimicking SLG induced by several lipogenic agents (arachidonic acid, anandamide, linoleic acid + testosterone; Nile Red; 48‐hr treatments). Moreover, it exerted significant anti‐proliferative actions (CyQUANT‐assay), and increased [Ca²⁺]_IC (Fluo‐4 AM‐based Ca²⁺‐measurement). Although NA did not prevent the lipopolysaccharide‐induced pro‐inflammatory response (up‐regulation [Q‐PCR] and release [ELISA] of several pro‐inflammatory cytokines) of the sebocytes, collectively, these data support the concept that NA may be effective in suppressing sebum production in vivo. While exploring the mechanism of the sebostatic actions, we found that sebocytes express HCA₂ (Q‐PCR, immunofluorescent labelling), siRNA‐mediated silencing of which prevented the NA‐induced Ca²⁺‐signal and the lipostatic action. Collectively, our data introduce NA, and HCA₂ activators in general, as novel, potent and most likely safe sebostatic agents, with possible anti‐acne potential.

Minor compounds from virgin olive oil attenuate LPS-induced inflammation via visfatin-related gene modulation on primary human monocytes

We have analyzed the effects of minor compounds found in the unsaponifiable fraction (UF) and in the phenolic fraction (PF) of virgin olive oil (VOO) on LPS-induced inflammatory response via visfatin modulation in human monocytes. For this purpose, monocytes were incubated with UF and PF at different concentrations and the pro-inflammatory stimulus LPS for 24 hr; squalene (SQ) and hydroxytyrosol (HTyr), the main components in UF and PF, respectively, were also used. The relative expression of both pro-inflammatory and anti-inflammatory genes, as well as other genes related to the NAD+-biosynthetic pathway was evaluated by RT-qPCR; and the secretion of some of these markers was assessed by ELISA procedures. We found that UF, SQ, PF, and HTyr prevented from LPS-induced dysfunctional gene expression and secretion via visfatin-related gene modulation in human monocytes. These findings unveil a potential beneficial role for minor compounds of VOO in the prevention of inflammatory-disorders. PRACTICAL APPLICATION: In this project, potential health benefits of VOO micronutrients (unsaponifiable and phenolic compounds) were confirmed through anti-inflammatory assays. Our results reveal new interesting researching goals concerning nutrition by considering the role of bioactive VOO compounds in the prevention and progress of diseases related to inflammation.

NAD metabolites interfere with proliferation and functional properties of THP-1 cells

Over the past few years the NAD-related compounds nicotinamide (NAM), nicotinamide riboside (NR) and 1-methylnicotinamide (MNA) have been established as important molecules in signalling pathways that contribute to metabolic functions of many cells, including those of the immune system. Among immune cells, monocytes/macrophages, which are the major players of inflammatory processes, are especially susceptible to the anti-inflammatory action of NAM. Here we asked whether NAM and the two other compounds have the potential to regulate differentiation and LPS-induced biological answers of the monocytic cell line THP-1. We show that treatment of THP-1 cells with NAM, NR and MNA resulted in growth retardation accompanied by enrichment of cells in the G0/G1-phase independent of p21 and p53. NAM and NR caused an increase in intracellular NAD concentrations and SIRT1 and PARP1 mRNA expression was found to be enhanced. The compounds failed to up-regulate the expression of the cell surface differentiation markers CD38, CD11b and CD14. They modulated the reactive oxygen species production and primed the cells to respond less effectively to the LPS induced TNF-α production. Our data show that the NAD metabolites interfere with early events associated with differentiation of THP-1 cells along the monocytic path and that they affect LPS-induced biological responses of the cell line.

Nicotinamide alleviates kidney injury and pregnancy outcomes in lupus-prone MRL/lpr mice treated with lipopolysaccharide

Systemic lupus erythematosus (SLE) increases the risk of preterm birth and preeclampsia (PE). The flares of SLE during pregnancy or after delivery are also problematic. We have previously demonstrated that nicotinamide (NAM), a non-teratogenic amide of vitamin B3, reduces inflammation and oxidative stress and improves PE-like phenotype and pregnancy outcomes in the mouse models of PE. The present study aimed to establish a model to investigate the pregnancy outcomes and flares of SLE in pregnant mice with SLE and to examine whether NAM is beneficial to pregnant mice with SLE. We used pregnant and non-pregnant lupus-prone MRL/lpr mice treated with or without a Toll-like receptor (TLR) ligand lipopolysaccharide (LPS) because TLR4 signaling reportedly exacerbates SLE and pregnancy; MRL/+ mice were used as controls. Blood pressure (BP) and urinary albumin excretion were increased only in the pregnant MRL/lpr-LPS mice. LPS together with pregnancy exacerbated glomerulonephritis, and the most severe inflammation was observed in the kidneys of the pregnant MRL/lpr-LPS mice. The shortening of pregnancy periods, increase in fetal demise percentage, and reduction in fetal weight were observed only in the pregnant MRL/lpr-LPS mice. NAM improved BP and kidney injury, prolonged pregnancy periods, and improved fetal growth in the pregnant MRL/lpr-LPS mice. The results suggest that SLE patients are prone to develop poor pregnancy outcome, and likely develop severe nephropathy and kidney inflammation. NAM may be a novel therapeutic option that improves kidney injury and pregnancy outcomes, thereby benefiting pregnant patients with SLE.

Strong binding active constituents of phytochemical to BMPR1A promote bone regeneration: In vitro, in silico docking, and in vivo studies

Two of the most problematic orthopedic and neurosurgeon visits are associated with spine and craniofacial fractures. Therefore, more attention needs to be paid to finding a medicine to repair these fractures. Amongst the most mysterious herbs, Aloe vera stands out. In the present study, the ameliorating function of A. vera on osteogenesis was studied in vitro and in vivo. Osteoblast-like cells were exposed to A. vera, followed by analysis of cell viability, lactate dehydrogenase release, and intracellular reactive oxygen species (ROS) production. The results showed an enhanced cell biocompatibility in a dose-dependent manner due to attenuated intracellular ROS production. Furthermore, a docking study indicated that the strong affinity of A. vera constituents to type I bone morphogenic protein receptor (BMPR1A) without the involvement of the BMPR1A chain B. The induction of osteogenesis prompts extracellular calcium deposition by osteoblasts, which affirms successful in vitro bone regeneration. However, injection of A. vera in rats with critical size calvarial defects induced Runx2, alkaline phosphatase (ALP), OCN, and BMP2 genes overexpression, which led to the formation of victorious bone with enhanced bone density and ALP activity. It is worthy to note that Aloin has the highest affinity to BMPR1A, whereas there are no reports regarding the impact of Aloenin, Aloesin, and γ-sitosterol on osteogenesis. Furthermore, some of them have antitumor potency, and it might be proposed that they are considered as a bone substitute in the osteotomy site of osteosarcoma with the aim of bone recovery and suppression of osteosarcoma. The whole consequences of this investigation manifests the plausibility of using A. vera as an antioxidant and osteoconductive substitute.

Olive oil and postprandial hyperlipidemia: implications for atherosclerosis and metabolic syndrome

Olive oil is the primary source of fat in the Mediterranean diet, which is associated with a significant improvement in health status, as measured by reduced mortality from several chronic diseases. The current pandemic of obesity, metabolic syndrome, and type 2 diabetes is intimately associated with an atherogenic dyslipidemic phenotype. The core components of the dyslipidemia of the metabolic syndrome, which most likely initiate atherosclerosis, are the "lipid triad" consisting of high plasma triglycerides, low levels of high-density lipoproteins, and a preponderance of small, dense low-density lipoproteins at fasting. However, postprandial (non-fasting) TGs (postprandial hyperlipidemia) are also recognized as an important component for atherosclerosis. Herein, the purpose of this review was to provide an update on the effects and mechanisms related to olive oil on postprandial hyperlipidemia and its implications for the onset and progression of atherosclerosis and metabolic syndrome.

Nicotinamide metabolism regulates glioblastoma stem cell maintenance

Metabolic dysregulation promotes cancer growth through not only energy production, but also epigenetic reprogramming. Here, we report that a critical node in methyl donor metabolism, nicotinamide N-methyltransferase (NNMT), ranked among the most consistently overexpressed metabolism genes in glioblastoma relative to normal brain. NNMT was preferentially expressed by mesenchymal glioblastoma stem cells (GSCs). NNMT depletes S-adenosyl methionine (SAM), a methyl donor generated from methionine. GSCs contained lower levels of methionine, SAM, and nicotinamide, but they contained higher levels of oxidized nicotinamide adenine dinucleotide (NAD+) than differentiated tumor cells. In concordance with the poor prognosis associated with DNA hypomethylation in glioblastoma, depletion of methionine, a key upstream methyl group donor, shifted tumors toward a mesenchymal phenotype and accelerated tumor growth. Targeting NNMT expression reduced cellular proliferation, self-renewal, and in vivo tumor growth of mesenchymal GSCs. Supporting a mechanistic link between NNMT and DNA methylation, targeting NNMT reduced methyl donor availability, methionine levels, and unmethylated cytosine, with increased levels of DNA methyltransferases, DNMT1 and DNMT3A. Supporting the clinical significance of these findings, NNMT portended poor prognosis for glioblastoma patients. Collectively, our findings support NNMT as a GSC-specific therapeutic target in glioblastoma by disrupting oncogenic DNA hypomethylation.

Meat Intake and the Dose of Vitamin B3 - Nicotinamide: Cause of the Causes of Disease Transitions, Health Divides, and Health Futures?

Meat and vitamin B3 - nicotinamide - intake was high during hunter-gatherer times. Intake then fell and variances increased during and after the Neolithic agricultural revolution. Health, height, and IQ deteriorated. Low dietary doses are buffered by 'welcoming' gut symbionts and tuberculosis that can supply nicotinamide, but this co-evolved homeostatic metagenomic strategy risks dysbioses and impaired resistance to pathogens. Vitamin B3 deficiency may now be common among the poor billions on a low-meat diet. Disease transitions to non-communicable inflammatory disorders (but longer lives) may be driven by positive 'meat transitions'. High doses of nicotinamide lead to reduced regulatory T cells and immune intolerance. Loss of no longer needed symbiotic 'old friends' compounds immunological over-reactivity to cause allergic and auto-immune diseases. Inhibition of nicotinamide adenine dinucleotide consumers and loss of methyl groups or production of toxins may cause cancers, metabolic toxicity, or neurodegeneration. An optimal dosage of vitamin B3 could lead to better health, but such a preventive approach needs more equitable meat distribution. Some people may require personalised doses depending on genetic make-up or, temporarily, when under stress.

Meat and Nicotinamide: A Causal Role in Human Evolution, History, and Demographics

Hunting for meat was a critical step in all animal and human evolution. A key brain-trophic element in meat is vitamin B3 / nicotinamide. The supply of meat and nicotinamide steadily increased from the Cambrian origin of animal predators ratcheting ever larger brains. This culminated in the 3-million-year evolution of Homo sapiens and our overall demographic success. We view human evolution, recent history, and agricultural and demographic transitions in the light of meat and nicotinamide intake. A biochemical and immunological switch is highlighted that affects fertility in the 'de novo' tryptophan-to-kynurenine-nicotinamide 'immune tolerance' pathway. Longevity relates to nicotinamide adenine dinucleotide consumer pathways. High meat intake correlates with moderate fertility, high intelligence, good health, and longevity with consequent population stability, whereas low meat/high cereal intake (short of starvation) correlates with high fertility, disease, and population booms and busts. Too high a meat intake and fertility falls below replacement levels. Reducing variances in meat consumption might help stabilise population growth and improve human capital.

Dietary fatty acids on aortic root calcification in mice with metabolic syndrome

Metabolic syndrome (MetS) is associated with obesity, dyslipidemia, type 2 diabetes, and chronic low-grade inflammation.