Role of "Western diet" in inflammatory autoimmune diseases

Prolonged high-fat-diet feeding promotes non-alcoholic fatty liver disease and alters gut microbiota in mice

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) has become an epidemic largely due to the worldwide increase in obesity. While lifestyle modifications and pharmacotherapies have been used to alleviate NAFLD, successful treatment options are limited. One of the main barriers to finding safe and effective drugs for long-term use in NAFLD is the fast initiation and progression of disease in the available preclinical models. Therefore, we are in need of preclinical models that (1) mimic the human manifestation of NAFLD and (2) have a longer progression time to allow for the design of superior treatments.

AIM

To characterize a model of prolonged high-fat diet (HFD) feeding for investigation of the long-term progression of NAFLD.

METHODS

In this study, we utilized prolonged HFD feeding to examine NAFLD features in C57BL/6 male mice. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 80 wk to promote obesity (Old-HFD group, n = 18). A low-fat diet (LFD) (14% fat, 32% protein, and 54% carbohydrate) was administered for the same duration to age-matched mice (Old-LFD group, n = 15). An additional group of mice was maintained on the LFD (Young-LFD, n = 20) for a shorter duration (6 wk) to distinguish between age-dependent and age-independent effects. Liver, colon, adipose tissue, and feces were collected for histological and molecular assessments.

RESULTS

Prolonged HFD feeding led to obesity and insulin resistance. Histological analysis in the liver of HFD mice demonstrated steatosis, cell injury, portal and lobular inflammation and fibrosis. In addition, molecular analysis for markers of endoplasmic reticulum stress established that the liver tissue of HFD mice have increased phosphorylated Jnk and CHOP. Lastly, we evaluated the gut microbial composition of Old-LFD and Old-HFD. We observed that prolonged HFD feeding in mice increased the relative abundance of the Firmicutes phylum. At the genus level, we observed a significant increase in the abundance of Adercreutzia, Coprococcus, Dorea, and Ruminococcus and decreased relative abundance of Turicibacter and Anaeroplasma in HFD mice.

CONCLUSION

Overall, these data suggest that chronic HFD consumption in mice can mimic pathophysiological and some microbial events observed in NAFLD patients.

Diet-Microbe-Host Interactions That Affect Gut Mucosal Integrity and Infection Resistance

The gastrointestinal tract microbiome plays a critical role in regulating host innate and adaptive immune responses against pathogenic bacteria. Disease associated dysbiosis and environmental induced insults, such as antibiotic treatments can lead to increased susceptibility to infection, particularly in a hospital setting. Dietary intervention is the greatest tool available to modify the microbiome and support pathogen resistance. Some dietary components can maintain a healthy disease resistant microbiome, whereas others can contribute to an imbalanced microbial population, impairing intestinal barrier function and immunity. Characterizing the effects of dietary components through the host-microbe axis as it relates to gastrointestinal health is vital to provide evidence-based dietary interventions to mitigate infections. This review will cover the effect of dietary components (carbohydrates, fiber, proteins, fats, polyphenolic compounds, vitamins, and minerals) on intestinal integrity and highlight their ability to modulate host-microbe interactions as to improve pathogen resistance.

Role for diet in normal gut barrier function: developing guidance within the framework of food-labeling regulations

A reduction in intestinal barrier function is currently believed to play an important role in pathogenesis of many diseases, as it facilitates passage of injurious factors such as lipopolysaccharide, peptidoglycan, whole bacteria, and other toxins to traverse the barrier to damage the intestine or enter the portal circulation. Currently available evidence in animal models and in vitro systems has shown that certain dietary interventions can be used to reinforce the intestinal barrier to prevent the development of disease. The relevance of these studies to human health is unknown. Herein, we define the components of the intestinal barrier, review available modalities to assess its structure and function in humans, and review the available evidence in model systems or perturbations in humans that diet can be used to fortify intestinal barrier function. Acknowledging the technical challenges and the present gaps in knowledge, we provide a conceptual framework by which evidence could be developed to support the notion that diet can reinforce human intestinal barrier function to restore normal function and potentially reduce the risk for disease. Such evidence would provide information on the development of healthier diets and serve to provide a framework by which federal agencies such as the US Food and Drug Administration can evaluate evidence linking diet with normal human structure/function claims focused on reducing risk of disease in the general public.

The Gut Microbiome in Inflammatory Bowel Disease: Lessons Learned From Other Immune-Mediated Inflammatory Diseases

There is a growing appreciation for the role of the gut microbiome in human health and disease. Aided by advances in sequencing technologies and analytical methods, recent research has shown the healthy gut microbiome to possess considerable diversity and functional capacity. Dysbiosis of the gut microbiota is believed to be involved in the pathogenesis of not only diseases that primarily affect the gastrointestinal tract but also other less obvious diseases, including neurologic, rheumatologic, metabolic, hepatic, and other illnesses. Chronic immune-mediated inflammatory diseases (IMIDs) represent a group of diseases that share many underlying etiological factors including genetics, aberrant immunological responses, and environmental factors. Gut dysbiosis has been reported to be common to IMIDs as a whole, and much effort is currently being directed toward elucidating microbiome-mediated disease mechanisms and their implications for causality. In this review, we discuss gut microbiome studies in several IMIDs and show how these studies can inform our understanding of the role of the gut microbiome in inflammatory bowel disease.

The Case for a More Holistic Approach to Dry Eye Disease: Is It Time to Move beyond Antibiotics?

Dry eye disease (DED) is one of the most frequent presentations to optometrists with over 16 million US adults (6.8% of adult population) diagnosed as having this disorder. The majority of associated marketed products offer relief from symptomatology but do not address aetiology. DED harbours many distinguishing features of a chronic inflammatory disorder. The recent explosion in human microbiome research has sparked interest in the ocular microbiome and its role in the preservation and extension of ocular surface health and in the contribution of the gut microbiome to chronic systemic inflammation and associated "Western life-style" diseases. With a significant lack of success for many patients using currently available DED treatments, in this era of the microbiome, we are interested in exploring potential novel therapies that aim to reconstitute healthy bacterial communities both locally and distally (in the gut) as a treatment for DED. Although this direction of investigation is in its infancy, burgeoning interest makes such a review timely. This paper considers a number of studies into the use functional foods and associated products to ameliorate dry eye.

Nicotinamide as Independent Variable for Intelligence, Fertility, and Health: Origin of Human Creative Explosions?

Meat and nicotinamide acquisition was a defining force during the 2-million-year evolution of the big brains necessary for, anatomically modern, Homo sapiens to survive. Our next move was down the food chain during the Mesolithic 'broad spectrum', then horticultural, followed by the Neolithic agricultural revolutions and progressively lower average 'doses' of nicotinamide. We speculate that a fertility crisis and population bottleneck around 40 000 years ago, at the time of the Last Glacial Maximum, was overcome by Homo (but not the Neanderthals) by concerted dietary change plus profertility genes and intense sexual selection culminating in behaviourally modern Homo sapiens. Increased reliance on the 'de novo' synthesis of nicotinamide from tryptophan conditioned the immune system to welcome symbionts, such as TB (that excrete nicotinamide), and to increase tolerance of the foetus and thereby fertility. The trade-offs during the warmer Holocene were physical and mental stunting and more infectious diseases and population booms and busts. Higher nicotinamide exposure could be responsible for recent demographic and epidemiological transitions to lower fertility and higher longevity, but with more degenerative and auto-immune disease.

High Salt Inhibits Tumor Growth by Enhancing Anti-tumor Immunity

Excess salt intake could affect the immune system by shifting the immune cell balance toward a pro-inflammatory state. Since this shift of the immune balance is thought to be beneficial in anti-cancer immunity, we tested the impact of high salt diets on tumor growth in mice. Here we show that high salt significantly inhibited tumor growth in two independent murine tumor transplantation models. Although high salt fed tumor-bearing mice showed alterations in T cell populations, the effect seemed to be largely independent of adaptive immune cells. In contrast, depletion of myeloid-derived suppressor cells (MDSCs) significantly reverted the inhibitory effect on tumor growth. In line with this, high salt conditions almost completely blocked murine MDSC function in vitro. Importantly, similar effects were observed in human MDSCs isolated from cancer patients. Thus, high salt conditions seem to inhibit tumor growth by enabling more pronounced anti-tumor immunity through the functional modulation of MDSCs. Our findings might have critical relevance for cancer immunotherapy.

Relationship between the Intake of n-3 Polyunsaturated Fatty Acids and Depressive Symptoms in Elderly Japanese People: Differences According to Sex and Weight Status

n-3 polyunsaturated fatty acids (PUFAs) have been shown to have preventive effects against depression. In this study, we aimed to investigate the associations between the intake of n-3 PUFAs and depression among people according to sex and weight status. We utilized cross-sectional data from the Shika study in Japan. The study was conducted between 2013 and 2016. Data were collected from adults older than 65 years. Invitation letters were distributed to 2677 individuals, 2470 of whom participated in the study (92.3%). We assessed depressive states using the Japanese short version of the Geriatric Depression Scale (GDS-15). We assessed the intake of n-3 PUFAs using the validated food frequency questionnaire. One thousand six hundred thirty-three participants provided data, among which 327 (20.0%) exhibited depressive symptoms. When we performed the stratified analysis by sex and weight status, there were significant inverse relationships between total n-3 PUFAs, individual n-3 PUFAs, and n-3/n-6 PUFAs ratio and depressive symptoms in overweight/obese females. No correlations were observed between n-3 PUFAs intake and depressive states in males. The results demonstrated a relationship between n-3 PUFAs deficiencies and depressive states, particularly in overweight/obese females. Dietary modifications may help to prevent depressive symptoms in overweight/obese females.

Sodium in the microenvironment regulates immune responses and tissue homeostasis

During tissue inflammation, immune cells infiltrate the interstitial space of target organs, where they sense and adapt to local environmental stimuli. Such stimuli include not only pathogens but also local factors such as the levels of oxygenation, nutrients and electrolytes. An important electrolyte in this regard is sodium (Na+). Recent in vivo findings have shown a role of Na+ storage in the skin for electrolyte homeostasis. Thereby, Na+ intake may influence the activation status of the immune system through direct effects on T helper cell subsets and innate immune cells in tissues such as the skin and other target organs. Furthermore, high Na+ intake has been shown to alter the composition of the intestinal microbiota, with indirect effects on immune cells. The results suggest regulatory roles for Na+ in cardiovascular disease, inflammation, infection and autoimmunity.

Interplay of Na+ Balance and Immunobiology of Dendritic Cells

Local Na⁺ balance emerges as an important factor of tissue microenvironment. On the one hand, immune cells impact on local Na⁺ levels. On the other hand, Na⁺ availability is able to influence immune responses. In contrast to macrophages, our knowledge of dendritic cells (DCs) in this state of affair is rather limited. Current evidence suggests that the impact of increased Na⁺ on DCs is context dependent. Moreover, it is conceivable that DC immunobiology might also be influenced by Na⁺-rich-diet-induced changes of the gut microbiome.

The Impact of Intermittent Fasting (Ramadan Fasting) on Psoriatic Arthritis Disease Activity, Enthesitis, and Dactylitis: A Multicentre Study

Intermittent circadian fasting, namely Ramadan, is a common worldwide practice. Such fasting has a positive impact on psoriasis, but no data exist on its role in psoriatic arthritis (PsA)-a disease that is clearly linked to body mass index. We enrolled 37 patients (23 females and 14 males) with a mean age 43.32 ± 7.81 and they fasted for 17 h for one month in 2016. The baseline PsA characteristics were collected and 12 (32.4%) patients had peripheral arthritis, 13 (35.1%) had axial involvement, 24 (64.9%) had enthesitis, and 13 (35.1%) had dactylitis. Three patients (8.1%) were treated with methotrexate, 28 (75.7%) with TNF-α blockers, and 6 (16.2%) with IL-17 blockers. After a month of intermittent fasting, C-reactive protein (CRP) levels decreased from 14.08 ± 4.65 to 12.16 ± 4.46 (p < 0.0001), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) decreased from 2.83 ± 1.03 to 2.08 ± 0.67 (p = 0.0078), Psoriasis Area Severity Index (PASI) decreased from 7.46 ± 2.43 to 5.86 ± 2.37 (p < 0.0001), and Disease Activity index for PSoriatic Arthritis (DAPSA) decreased from 28.11 ± 4.51 to 25.76 ± 4.48 (p < 0.0001). Similarly, enthesitis improved after fasting, with Leeds Enthesitis Index (LEI) decreasing from 2.25 ± 1.11 to 1.71 ± 0.86 (p < 0.0001) and dactylitis severity score (DSS) decreasing from 9.92 ± 2.93 to 8.54 ± 2.79 (p = 0.0001). Fasting was found to be a predictor of a decrease in PsA disease activity scores (DAPSA, BASDAI, LEI, DSS) even after adjustment for weight loss. IL-17 therapy was found to be an independent predictor of decreases in LEI after fasting. These preliminary data may support the use of chronomedicine in the context of rheumatic diseases, namely PsA. Further studies are needed to support our findings.

Lactobacillus rhamnosus GG strain mitigated the development of obstructive sleep apnea-induced hypertension in a high salt diet via regulating TMAO level and CD4+ T cell induced-type I inflammation

Obstructive sleep apnea (OSA) and high salt content in modern diet has been particularly implicated in systemic hypertension, leading to increased morbidity and mortality. Gut dysbiosis, associated with increased risk of systemic immunological imbalance, plays a causal role in the development of cardiovascular diseases. Here, we investigated the effect of Lactobacillus rhamnosus GG strain (LGG) on the development of hypertension induced by OSA and high salt diet. In this study, hypertension was modeled in rats by feeding a high salt diet (HSD) for 6 wk and exposuring to chronic intermittent hypoxia (CIH) during the sleep cycle. We found that OSA combined with HSD increased the severity of hypertension through increasing level of blood Trimethylamine-Oxide (TMAO), release of Th1-related cytokine (IFN-γ) and inhibition of anti-inflammatory cytokine (TGF-β1), and affected the gut microbiome in rats, particularly by depleting Lactobacillus. In addition, expression of PERK1/2, PAkt and PmTOR increased in the aorta from rats with a CIH exposure and HSD. Consequently, treatment of model rats with LGG prevented aggravation of hypertension by reducing blood TMAO levels, modulating Th1/Th2 cytokine imbalance and suppressing phosphorylation levels of ERK1/2, Akt and mTOR. In line with these findings, our results connect high salt diet to the gut-immune axis and highlight the gut microbiome as a potential therapeutic target to counteract the development of OSA-induced hypertension basing on a high salt diet.

Short-Term Mediterranean Diet Improves Endurance Exercise Performance: A Randomized-Sequence Crossover Trial

Objective: Healthful dietary patterns have constituents that are known to improve exercise performance, such as antioxidants, nitrates, and alkalizing effects. However, ergogenic effects of such diets have not been evaluated. We hypothesized that a short-term Mediterranean diet results in better exercise performance, as compared to a typical Western diet. Methods: Eleven recreationally active women (n = 7) and men (n = 4) (body mass index, 24.6 ± 3.2 kg/m²; age 28 ± 3 years) were studied in a randomized-sequence crossover study, in which they underwent exercise performance testing on one occasion after 4 days of a Mediterranean diet and on another occasion after 4 days of a Western diet. A 9- to 16-day washout period separated the two trials. Endurance exercise performance was evaluated with a 5-km treadmill time trial. Anaerobic exercise performance tests included a Wingate cycle test, a vertical jump test, and hand grip dynamometry. Results: Five-kilometer run time was 6% ± 3% shorter (faster) in the Mediterranean diet trial than in the Western diet trial (27.09 ± 3.55 vs 28.59 ± 3.21 minutes; p = 0.030) despite similar heart rates (160 ± 5 vs 160 ± 4 beats/min; p = 0.941) and ratings of perceived exertion (14.6 ± 0.5 vs 15.0 ± 0.5; p = 0.356). No differences between the diet conditions were observed for anaerobic exercise tests, including peak and mean power from the Wingate test (both p ≥ 0.05), the vertical jump test (p = 0.19), and the hand grip strength test (p = 0.69). Conclusions: Our findings extend existing evidence of the health benefits of the Mediterranean diet by showing that this diet is also effective for improving endurance exercise performance in as little as 4 days. Further studies are warranted to determine whether a longer-term Mediterranean diet provides greater benefits and whether it might also be beneficial for anaerobic exercise performance and muscle strength and power.

Western diet regulates immune status and the response to LPS-driven sepsis independent of diet-associated microbiome

Sepsis is a deleterious immune response to infection that leads to organ failure and is the 11th most common cause of death worldwide. Despite plaguing humanity for thousands of years, the host factors that regulate this immunological response and subsequent sepsis severity and outcome are not fully understood. Here we describe how the Western diet (WD), a diet high in fat and sucrose and low in fiber, found rampant in industrialized countries, leads to worse disease and poorer outcomes in an LPS-driven sepsis model in WD-fed mice compared with mice fed standard fiber-rich chow (SC). We find that WD-fed mice have higher baseline inflammation (metaflammation) and signs of sepsis-associated immunoparalysis compared with SC-fed mice. WD mice also have an increased frequency of neutrophils, some with an "aged" phenotype, in the blood during sepsis compared with SC mice. Importantly, we found that the WD-dependent increase in sepsis severity and higher mortality is independent of the microbiome, suggesting that the diet may be directly regulating the innate immune system through an unknown mechanism. Strikingly, we could predict LPS-driven sepsis outcome by tracking specific WD-dependent disease factors (e.g., hypothermia and frequency of neutrophils in the blood) during disease progression and recovery. We conclude that the WD is reprogramming the basal immune status and acute response to LPS-driven sepsis and that this correlates with alternative disease paths that lead to more severe disease and poorer outcomes.

Investigating the aetiology of adverse events following HPV vaccination with systems vaccinology

In contrast to the insidious and poorly immunogenic human papillomavirus (HPV) infections, vaccination with the HPV virus-like particles (vlps) is non-infectious and stimulates a strong neutralizing-antibody response that protects HPV-naïve vaccinees from viral infection and associated cancers. However, controversy about alleged adverse events following immunization (AEFI) with the vlps have led to extensive reductions in vaccine acceptance, with countries like Japan dropping it altogether. The AEFIs are grouped into chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). In this review, we present a hypothesis that the AEFIs might arise from malfunctions within the immune system when confronted with the unusual antigen. In addition, we outline how the pathophysiology of the AEFIs can be cost-effectively investigated with the holistic principles of systems vaccinology in a two-step process. First, comprehensive immunological profiles of HPV vaccinees exhibiting the AEFIs are generated by integrating the data derived from serological profiling for prominent HPV antibodies and serum cytokines, with data from serum metabolomics, peripheral white blood cells transcriptomics and gut microbiome profiling. Next, the immunological profiles are compared with corresponding profiles generated for matched (a) HPV vaccinees without AEFIs; (b) non-HPV-vaccinated individuals with CFS/ME-like symptoms; and (c) non-HPV-vaccinated individuals without CFS/ME. In these comparisons, any causal links between HPV vaccine and the AEFIs, as well as the underlying molecular basis for the links will be revealed. Such a study should provide an objective basis for evaluating HPV vaccine safety and for identifying biomarkers for individuals at risk of developing AEFI with HPV vaccination.

Pediatric Obesity and the Immune System

Obesity has reached pandemic proportion and represents a major risk for several comorbidities. In addition to metabolic and cardiovascular obesity-related diseases, recent evidence suggested that obesity might affect immune system function. Adipose tissue is considered an endocrine organ that actively secretes cytokines also referred to as "adipokines." Adipokines play an important role in the control of human metabolism. The dysfunctional adipose tissue in obese individuals is characterized by an altered cytokine secretion pattern that promotes chronic low-grade inflammation. Epidemiological evidence highlights the association between obesity and allergic and immune-mediated diseases, such as asthma, allergic rhinitis, rheumatic arthritis, and psoriasis. Less is known about underlying pathogenic mechanisms. However, several recent in vivo and in vitro studies have reported that adipokines are involved in inflammatory and autoimmune disorders by influencing both innate and acquired immune responses. In addition, obesity has been associated with reduced immune surveillance and increased risk of cancer. This paper reviews the evidence regarding the role of adipokines in immune system regulation, with particular emphasis on autoimmune, allergic, and inflammatory disorders. Understanding how obesity affects immune system functions may enable researchers to find new potential therapeutic targets in the management of allergic and autoimmune diseases.

You are what you eat: diet, health and the gut microbiota

Since the renaissance of microbiome research in the past decade, much insight has accumulated in comprehending forces shaping the architecture and functionality of resident microorganisms in the human gut. Of the multiple host-endogenous and host-exogenous factors involved, diet emerges as a pivotal determinant of gut microbiota community structure and function. By introducing dietary signals into the nexus between the host and its microbiota, nutrition sustains homeostasis or contributes to disease susceptibility. Herein, we summarize major concepts related to the effect of dietary constituents on the gut microbiota, highlighting chief principles in the diet-microbiota crosstalk. We then discuss the health benefits and detrimental consequences that the interactions between dietary and microbial factors elicit in the host. Finally, we present the promises and challenges that arise when seeking to incorporate microbiome data in dietary planning and portray the anticipated revolution that the field of nutrition is facing upon adopting these novel concepts.

Theoretical Explanation for Reduced Body Mass Index and Obesity Rates in Cannabis Users

Introduction: Obesity is treatment-resistant, and is linked with a number of serious, chronic diseases. Adult obesity rates in the United States have tripled since the early 1960s. Recent reviews show that an increased ratio of omega-6 to omega-3 fatty acids contributes to obesity rates by increasing levels of the endocannabinoid signals AEA and 2-AG, overstimulating CB₁R and leading to increased caloric intake, reduced metabolic rates, and weight gain. Cannabis, or THC, also stimulates CB₁R and increases caloric intake during acute exposures. Goals: To establish the relationship between Cannabis use and body mass index, and to provide a theoretical explanation for this relationship. Results: The present meta-analysis reveals significantly reduced body mass index and rates of obesity in Cannabis users, in conjunction with increased caloric intake. Theoretical explanation: We provide for the first time a causative explanation for this paradox, in which rapid and long-lasting downregulation of CB₁R following acute Cannabis consumption reduces energy storage and increases metabolic rates, thus reversing the impact on body mass index of elevated dietary omega-6/omega-3 ratios.

Microbial transglutaminase: A new potential player in celiac disease

Microbial transglutaminase is heavily used in the food processing industries to improve food qualities. Being a protein's glue, by cross-linking it creates neoepitope complexes that are immunogenic and potentially pathogenic in celiac disease. Despite low sequence identity, it imitates functionally its family member, the endogenous tissue transglutaminase, which is the autoantigen of celiac disease. The present comprehensive review highlights the enzyme characteristics, endogenous and exogenous intestinal sources, its cross-talks with gluten and gliadin, its immunogenicity and potential pathogenicity and risks for the gluten induced conditions. If substantiated, it might represent a new environmental inducer of celiac disease. The present findings might affect nutritional product labeling, processed food additive policies and consumer health education.

Effect of dietary additives on intestinal permeability in both Drosophila and a human cell co-culture

Increased intestinal barrier permeability has been correlated with aging and disease, including type 2 diabetes, Crohn's disease, celiac disease, multiple sclerosis and irritable bowel syndrome. The prevalence of these ailments has risen together with an increase in industrial food processing and food additive consumption. Additives, including sugar, metal oxide nanoparticles, surfactants and sodium chloride, have all been suggested to increase intestinal permeability. We used two complementary model systems to examine the effects of food additives on gut barrier function: a Drosophila in vivo model and an in vitro human cell co-culture model. Of the additives tested, intestinal permeability was increased most dramatically by high sugar. High sugar also increased feeding but reduced gut and overall animal size. We also examined how food additives affected the activity of a gut mucosal defense factor, intestinal alkaline phosphatase (IAP), which fluctuates with bacterial load and affects intestinal permeability. We found that high sugar reduced IAP activity in both models. Artificial manipulation of the microbiome influenced gut permeability in both models, revealing a complex relationship between the two. This study extends previous work in flies and humans showing that diet can play a role in the health of the gut barrier. Moreover, simple models can be used to study mechanisms underlying the effects of diet on gut permeability and function.This article has an associated First Person interview with the first author of the paper.

Nonhuman Primates and Translational Research-Cardiovascular Disease

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in the United States. Human epidemiological studies provide challenges for understanding mechanisms that regulate initiation and progression of CVD due to variation in lifestyle, diet, and other environmental factors. Studies describing metabolic and physiologic aspects of CVD, and those investigating genetic and epigenetic mechanisms influencing CVD initiation and progression, have been conducted in multiple Old World nonhuman primate (NHP) species. Major advantages of NHPs as models for understanding CVD are their genetic, metabolic, and physiologic similarities with humans, and the ability to control diet, environment, and breeding. These NHP species are also genetically and phenotypically heterogeneous, providing opportunities to study gene by environment interactions that are not feasible in inbred animal models. Each Old World NHP species included in this review brings unique strengths as models to better understand human CVD. All develop CVD without genetic manipulation providing multiple models to discover genetic variants that influence CVD risk. In addition, as each of these NHP species age, their age-related comorbidities such as dyslipidemia and diabetes are accelerated proportionally 3 to 4 times faster than in humans.In this review, we discuss current CVD-related research in NHPs focusing on selected aspects of CVD for which nonprimate model organism studies have left gaps in our understanding of human disease. We include studies on current knowledge of genetics, epigenetics, calorie restriction, maternal calorie restriction and offspring health, maternal obesity and offspring health, nonalcoholic steatohepatitis and steatosis, Chagas disease, microbiome, stem cells, and prevention of CVD.

In the absence of specific advice, what do patients eat and avoid? Results from a community based diet study in patients suffering from rheumatoid arthritis (RA) with a focus on potassium

Rheumatoid arthritis (RA) is a painful disabling difficult to treat disease. Clinicians and guidelines invariably focus on drugs. Diet is important but lacks robust data. We carried out a comprehensive analytical study in Indian (Asian) patients.

METHODS

141 consenting symptomatic chronic RA patients [mean age 46 years) center and 165 unrelated healthy control subjects (mean age 36 years) completed a a-priori validated food frequency questionnaire in a cross-sectional non-random design study under the supervision of a nutritionist. All patients were under standard rheumatology care. A 3 day retrospective recall record captured dietary data for all subjects. National Indian guidelines were adopted for diet analytics. Standard statistical analysis was carried out; significant p < 0.05.

RESULTS

Daily diet was found to be significantly deficient in calories and consumption of proteins, calcium and potassium when compared to healthy subjects. It was also inadequate for several nutrients when compacted to recommended daily allowance. The proportion of carbohydrates (65%), proteins (15%) and fat (25%) in daily diet was consistent with Indian standards (healthy). Women patients reported higher deficiency. 44% patients consumed vegetarian diet and showed lesser pain and better function compared to non-vegetarians (not significant). 44% patients reported dietary restriction; higher swollen joint counts in patients following any dietary restriction (p = 0.01) or Ayurveda (ancient Indian medicinal system) advise (p = 0.01) or consuming night shade vegetables (p = 0.002).

CONCLUSION

Dietary inadequacy and in particular for protein and potassium was identified in patients of RA. Any form of dietary restriction did not seem to improve RA. Specific dietary needs of RA patients and in particular impact of potassium deficiency needs further research.

Precision Medicine: The Role of the MSIDS Model in Defining, Diagnosing, and Treating Chronic Lyme Disease/Post Treatment Lyme Disease Syndrome and Other Chronic Illness: Part 2

We present a precision medical perspective to assist in the definition, diagnosis, and management of Post Treatment Lyme Disease Syndrome (PTLDS)/chronic Lyme disease. PTLDS represents a small subset of patients treated for an erythema migrans (EM) rash with persistent or recurrent symptoms and functional decline. The larger population with chronic Lyme disease is less understood and well defined. Multiple Systemic Infectious Disease Syndrome (MSIDS) is a multifactorial model for treating chronic disease(s), which identifies up to 16 overlapping sources of inflammation and their downstream effects. A patient symptom survey and a retrospective chart review of 200 patients was therefore performed on those patients with chronic Lyme disease/PTLDS to identify those variables on the MSIDS model with the greatest potential effect on regaining health. Results indicate that dapsone combination therapy decreased the severity of eight major Lyme symptoms, and multiple sources of inflammation (other infections, immune dysfunction, autoimmunity, food allergies/sensitivities, leaky gut, mineral deficiencies, environmental toxins with detoxification problems, and sleep disorders) along with downstream effects of inflammation may all affect chronic symptomatology. In part two of our observational study and review paper, we postulate that the use of this model can represent an important and needed paradigm shift in the diagnosis and treatment of chronic disease.

Assessment of Biochemical and Densitometric Markers of Calcium-Phosphate Metabolism in the Groups of Patients with Multiple Sclerosis Selected due to the Serum Level of Vitamin D3

Background

In addition to the widely known effect of vitamin D₃ (vitD₃) on the skeleton, its role in the regulation of the immune response was also confirmed.

Aim

The assessment of biochemical and densitometric markers of calcium-phosphate metabolism in the groups of patients with relapsing-remitting multiple sclerosis (RRMS) selected due to the serum level of vitamin D₃.

Methods

The concentrations of biochemical markers and indices of lumbar spine bone densitometry (DXA) were determined in 82 patients divided into vitamin D₃ deficiency (VitDd), insufficiency (VitDi), and normal vitamin D₃ level (VitDn) subgroups.

Results

The highest level of the parathyroid hormone (PTH) and the highest prevalence of hypophosphatemia and osteopenia were demonstrated in VitDd group compared to VitDi and VitDn. However, in VitDd, VitDi, and VitDn subgroups no significant differences were observed in the levels of alkaline phosphatase (ALP) and ionized calcium (Ca²⁺) and in DXA indices. A negative correlation was observed between the level of vitamin D₃ and the Expanded Disability Status Scale (EDSS) in the whole MS group. The subgroups were significantly different with respect to the EDSS scores and the frequency of complaints related to walking according to the EQ-5D.

Conclusions

It is necessary to assess calcium-phosphate metabolism and supplementation of vitamin D₃ in RRMS patients. The higher the clinical stage of the disease assessed with the EDSS, the lower the level of vitamin D₃ in blood serum. Subjectively reported complaints related to difficulties with walking were reflected in the EDSS in VitDd patients.

Are we really what we eat? Nutrition and its role in the onset of rheumatoid arthritis

Accumulating research evidence suggests that individual dietary factors and dietary patterns might be implicated in the risk of development of rheumatoid arthritis (RA). This narrative review aims to present this evidence and provide nutritional recommendations for reducing RA risk in susceptible individuals. Overall, a 'Western' type diet rich in energy intake, total and saturated fat, an unbalanced ratio of n-3 to n-6 fatty acids, high in refined carbohydrates and sugar and low in fiber and antioxidants might increase the risk of RA both directly through increasing inflammation and indirectly through increasing insulin resistance and obesity, with the latter being a known risk factor for RA. On the contrary, consumption of long-chain omega-3 polyunsaturated fatty acids, derived from fish and fish oil, is associated with a reduced risk of RA probably due to their anti-inflammatory properties. The Mediterranean diet (MD), rich in plant-based foods such as wholegrains, legumes, fruit, vegetables, extra-virgin olive oil and low in red meat consumption, might have the potential to reduce the risk of RA. Based on current research evidence, it is suggested that adherence to the MD enhanced with an increased consumption of fatty fish, reduced consumption of sugar-sweetened drinks and maintenance of a normal body weight, contributes to reducing the risk of RA. Further research on RA susceptibility will allow for more specific dietary recommendations to be made.

Deregulation of SGK1 in Ulcerative Colitis: A Paradoxical Relationship Between Immune Cells and Colonic Epithelial Cells

BACKGROUND

Inflammatory bowel disease (IBD) is due to the interaction of genetic and environmental factors that trigger an unbalanced immune response ultimately resulting in the peculiar inflammatory reaction. Experimental models of IBD point to a role of T-cell-derived cytokines (Th17) and to SGK1 as mediator of the Th17 switch. We hypothesize that SGK1, a salt inducible kinase, directs lymphocytic behavior and tissue damage.

METHODS

Eleven controls and 32 ulcerative colitis (UC) patients were randomized according to endoscopic Mayo score. Mucosal biopsies from different intestinal tracts were analyzed by immunohistochemistry and quantitative real-time polymerase chain reaction to check the expression of disease markers including SGK1. Peripheral blood mononuclear cells (PBMCs) from patients and controls were analyzed by fluorescence-activated cell sorting. Finally, an in vitro cell model was developed to test the hypothesis.

RESULTS

SGK1 mRNA and protein expression in lesional areas of UC patients were lower than in normal peri-lesional areas of the same patients and in normal tissues of healthy controls. SGK1 expression was increased in PBMCs from UC patients, particularly in the CD4+ cell population, enriched in Th17 cells. IL17/IL13 was increased in patients and correlated with SGK1 expression. Genetically engineered Jurkat cells confirmed the effect of SGK1 overexpression on viability of RKO cells.

CONCLUSIONS

These observations suggest a pathogenic mechanism whereby SGK1 overexpression in CD4+ T cells induces the secretion of the inflammatory cytokines IL17 and IL13, which downregulate the expression of SGK1 in target tissues. Our data suggest a novel hypothesis in the pathogenesis of UC, integrating colonic epithelial cells and lymphocytes.

Empirically derived dietary patterns and serum inflammatory markers in Iranian female teachers: A cross-sectional study

AIM

To examine the relationship between dietary patterns and inflammatory markers including serum high sensitivity C-reactive protein (hs-CRP) and interleukin 17A (IL-17A) in females.

METHODS

In the present cross-sectional study in female teachers living in Yazd, central Iran, data on anthropometric measurements and general information were gathered. A food frequency questionnaire was completed by participants and then, subjects were invited to give blood samples. Major dietary patterns were derived using principal component analysis and serum inflammatory markers were compared according to quintiles of dietary patterns scores.

RESULTS

In total, 320 subjects aged 40.38 ± 8.08 years were included. Three dietary patterns were derived: (i) 'traditional' with a high intake of poultry, salt, eggs, other vegetables and red meat; (ii) 'vegetables and fruits' with a higher intake of tomatoes, yoghurt drinks, green leafy vegetables, dried fruits, fruits, other vegetables and organ meats and (iii) 'dairy and saturated fat' with a high loading of high-fat dairy products, butter, low-fat dairy, margarine, eggs, other vegetables and green leafy vegetables. Participants in the highest quintile of the 'vegetables and fruits' dietary pattern had significantly lower serum hs-CRP levels compared to those in the lowest quintile (3.6 ± 0.4 mg/L vs 2.6 ± 0.4 mg/L, respectively; P < 0.05). None of the dietary patterns were associated with circulating IL-17 levels.

CONCLUSIONS

Higher consumption of fruits and vegetables is inversely associated with serum hs-CRP but not IL-17 levels. Studies investigating the dietary patterns in association with IL-17 in other populations are recommended.

Intermittent living; the use of ancient challenges as a vaccine against the deleterious effects of modern life - A hypothesis

Chronic non-communicable diseases (CNCD) are the leading cause of mortality in developed countries. They ensue from the sum of modern anthropogenic risk factors, including high calorie nutrition, malnutrition, sedentary lifestyle, social stress, environmental toxins, politics and economic factors. Many of these factors are beyond the span of control of individuals, suggesting that CNCD are inevitable. However, various studies, ours included, show that the use of intermittent challenges with hormetic effects improve subjective and objective wellbeing of individuals with CNCD, while having favourable effects on immunological, metabolic and behavioural indices. Intermittent cold, heat, fasting and hypoxia, together with phytochemicals in multiple food products, have widespread influence on many pathways related with overall health. Until recently, most of the employed challenges with hormetic effects belonged to the usual transient live experiences of our ancestors. Our hypothesis; we conclude that, whereas the total inflammatory load of multi-metabolic and psychological risk factors causes low grade inflammation and aging, the use of intermittent challenges, united in a 7-10 days lasting hormetic intervention, might serve as a vaccine against the deleterious effects of chronic low grade inflammation and it's metabolic and (premature) aging consequences.

Unravelling the Roles of Susceptibility Loci for Autoimmune Diseases in the Post-GWAS Era

Although genome-wide association studies (GWAS) have identified several hundred loci associated with autoimmune diseases, their mechanistic insights are still poorly understood. The human genome is more complex than single nucleotide polymorphisms (SNPs) that are interrogated by GWAS arrays. Apart from SNPs, it also comprises genetic variations such as insertions-deletions, copy number variations, and somatic mosaicism. Although previous studies suggest that common copy number variations do not play a major role in autoimmune disease risk, it is possible that certain rare genetic variations with large effect sizes are relevant to autoimmunity. In addition, other layers of regulations such as gene-gene interactions, epigenetic-determinants, gene and environmental interactions also contribute to the heritability of autoimmune diseases. This review focuses on discussing why studying these elements may allow us to gain a more comprehensive understanding of the aetiology of complex autoimmune traits.

Long-term reprogramming of the innate immune system

During the last few years, a growing body of evidence has shown that immunological memory is not an exclusive trait of lymphocytes, as many inflammatory insults can alter the functionality and the responsiveness of the innate immune system in the long term. Innate immune cells, such as monocytes, macrophages, dendritic cells, and NK cells can be influenced by the encounters with inflammatory stimuli, undergoing functional reprogramming and developing changed responses to subsequent chellenges. The long-term reprogramming depends on the rewiring of cell metabolism and epigenetic processes, and they stay at the basis of induction of both innate immune memory (also termed trained immunity) and innate immune tolerance. Here, we review the central role that the effects of this long-term reprogramming of innate immune cells plays in a number of clinically relevant conditions such as vaccination, atherosclerosis, sepsis, and cancer.

Effect of prenatal EPA and DHA on maternal and umbilical cord blood cytokines

Background

Investigators have hypothesized that omega-3 fatty acid supplementation may modulate the immune response. However, available evidence is conflicting. We performed this study to investigate the effect of prenatal eicosapentaenoic acid (EPA)- and docosahexaenoic acid (DHA)-rich fish oil supplementation on maternal and fetal cytokine production.

Methods

This study is a secondary analysis of a randomized controlled trial designed to assess whether prenatal EPA- or DHA-rich fish oil supplementation would prevent perinatal depressive symptoms among women at risk. Enrolled participants received EPA-rich fish oil (1060 mg EPA plus 274 mg DHA), DHA-rich fish oil (900 mg DHA plus 180 mg EPA) or soy oil placebo. Maternal venous blood was collected at enrollment (12–20 weeks gestation) and after supplementation (34–36 weeks gestation). Umbilical cord blood was collected at delivery. We analyzed stored plasma specimens for 16 human cytokines using multiplex immunoassays. Maternal and cord blood cytokine levels were compared among the treatment groups. Associations of serum DHA and EPA with maternal and cord blood cytokines were explored via regression analysis.

Results

We enrolled 126 women, of whom 118 completed the trial. Prenatal supplementation with EPA-rich fish oil significantly lowered maternal IL6, IL15, and TNFα concentrations. However, supplementation with DHA-rich fish oil had no significant effect on maternal cytokine profiles. Maternal serum DHA fraction was significantly associated with IL1α, and maternal serum DHA and EPA fractions were significantly associated with IL 10 concentrations after supplementation. Compared with placebo, supplementation with EPA- or DHA-rich fish oils had no significant effect on cord blood cytokine concentrations.

Conclusions

Prenatal supplementation with EPA-rich fish oil significantly reduced levels of several inflammatory cytokines in maternal plasma, while prenatal DHA-rich fish oil had no significant effect on cytokine concentrations. Supplementation with EPA- and DHA- rich fish oil had no significant effect on umbilical cord blood cytokine concentrations.

Trial registration

Clinical Trial Registration: registration number NCT00711971 7/7/2008.

Salt, inflammation, IL-17 and hypertension

Traditionally, arterial hypertension and subsequent end-organ damage have been attributed to haemodynamic factors, but increasing evidence indicates that inflammation also contributes to the deleterious consequences of this disease. The immune system has evolved to prevent invasion of foreign microorganisms and to promote tissue healing after injury. However, this beneficial activity comes at a cost of collateral damage when the immune system overreacts to internal injury, such as prehypertension. Over the past few years, important findings have revolutionized hypertension research. Firstly, in 2007, a seminal paper showed that adaptive immunity is involved in the pathogenesis of hypertension. Secondly, salt storage in the skin and its consequences for cardiovascular physiology were discovered. Thirdly, after the discovery that salt promotes the differentiation of CD4⁺ T cells into T_H 17 cells, it was demonstrated that salt directly changes several cells of the innate and adaptive immune system and aggravates autoimmune disease but may improve antimicrobial defence. Herein, we will review pathways of activation of immune cells by salt in hypertension as the framework for understanding the multiple roles of salt and immunity in arterial hypertension and autoimmune disease. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.

Alopecia areata and the gut-the link opens up for novel therapeutic interventions

INTRODUCTION

This review aims to raise the potential of the modern society's impact on gut integrity often leading to increased intestinal permeability, as a cause or driver of Alopecia Areata (AA) in genetically susceptible people. With the increasing rate of T cell-driven autoimmunity, we hypothesize that there is a common root cause of these diseases that originates from chronic inflammation, and that the gut is the most commonly exposed area with our modern lifestyle. Areas covered: We will discuss the complexity in the induction of AA and its potential link to increased intestinal permeability. Our main focus will be on the gut microbiome and mechanisms involved in the interplay with the immune system that may lead to local and/or peripheral inflammation and finally, tissue destruction. Expert opinion: We have seen a link between AA and a dysfunctional gastrointestinal system which raised the hypothesis that an underlying intestinal inflammation drives the priming and dysregulation of immune cells that lead to hair follicle destruction. While it is still important to resolve local inflammation and restore the IP around the hair follicles, we believe that the root cause needs to be eradicated by long-term interventions to extinguish the fire driving the disease.

Intermittent Fasting Confers Protection in CNS Autoimmunity by Altering the Gut Microbiota

Multiple sclerosis (MS) is more common in western countries with diet being a potential contributing factor. Here we show that intermittent fasting (IF) ameliorated clinical course and pathology of the MS model, experimental autoimmune encephalomyelitis (EAE). IF led to increased gut bacteria richness, enrichment of the Lactobacillaceae, Bacteroidaceae, and Prevotellaceae families and enhanced antioxidative microbial metabolic pathways. IF altered T cells in the gut with a reduction of IL-17 producing T cells and an increase in regulatory T cells. Fecal microbiome transplantation from mice on IF ameliorated EAE in immunized recipient mice on a normal diet, suggesting that IF effects are at least partially mediated by the gut flora. In a pilot clinical trial in MS patients, intermittent energy restriction altered blood adipokines and the gut flora resembling protective changes observed in mice. In conclusion, IF has potent immunomodulatory effects that are at least partially mediated by the gut microbiome.

Enhanced 400-m sprint performance in moderately trained participants by a 4-day alkalizing diet: a counterbalanced, randomized controlled trial

Background

Sodium bicarbonate (NaHCO₃) is an alkalizing agent and its ingestion is used to improve anaerobic performance. However, the influence of alkalizing nutrients on anaerobic exercise performance remains unclear. Therefore, the present study investigated the influence of an alkalizing versus acidizing diet on 400-m sprint performance, blood lactate, blood gas parameters, and urinary pH in moderately trained adults.

Methods

In a randomized crossover design, eleven recreationally active participants (8 men, 3 women) aged 26.0 ± 1.7 years performed one trial under each individual’s unmodified diet and subsequently two trials following either 4 days of an alkalizing (BASE) or acidizing (ACID) diet. Trials consisted of 400-m runs at intervals of 1 week on a tartan track in a randomized order.

Results

We found a significantly lower 400-m performance time for the BASE trial (65.8 ± 7.2 s) compared with the ACID trial (67.3 ± 7.1 s; p = 0.026). In addition, responses were significantly higher following the BASE diet for blood lactate (BASE: 16.3 ± 2.7; ACID: 14.4 ± 2.1 mmol/L; p = 0.32) and urinary pH (BASE: 7.0 ± 0.7; ACID: 5.5 ± 0.7; p = 0.001).

Conclusions

We conclude that a short-term alkalizing diet may improve 400-m performance time in moderately trained participants. Additionally, we found higher blood lactate concentrations under the alkalizing diet, suggesting an enhanced blood or muscle buffer capacity. Thus, an alkalizing diet may be an easy and natural way to enhance 400-m sprint performance for athletes without the necessity of taking artificial dietary supplements.

Inflammatory bowel disease and immunonutrition: novel therapeutic approaches through modulation of diet and the gut microbiome

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract, thought to at least in part reflect an aberrant immune response to gut bacteria. IBD is increasing in incidence, particularly in populations that have recently immigrated to western countries. This suggests that environmental factors are involved in its pathogenesis. We hypothesize that the increase in IBD rates might reflect the consumption of an unhealthy Western diet, containing excess calories and lacking in key nutritional factors, such as fibre and vitamin D. Several recent studies have determined that dietary factors can dramatically influence the activation of immune cells and the mediators they release through a process called immunonutrition. Moreover, dietary changes can profoundly affect the balance of beneficial versus pathogenic bacteria in the gut. This microbial imbalance can alter levels of microbiota-derived metabolites that in turn can influence innate and adaptive intestinal immune responses. If the diet-gut microbiome disease axis does indeed underpin much of the 'western' influence on the onset and progression of IBD, then tremendous opportunity exists for therapeutic changes in lifestyle, to modulate the gut microbiome and to correct immune imbalances in individuals with IBD. This review highlights four such therapeutic strategies - probiotics, prebiotics, vitamin D and caloric restriction - that have the potential to improve and add to current IBD treatment regimens.

Harnessing the Power of Microbiome Assessment Tools as Part of Neuroprotective Nutrition and Lifestyle Medicine Interventions

An extensive body of evidence documents the importance of the gut microbiome both in health and in a variety of human diseases. Cell and animal studies describing this relationship abound, whilst clinical studies exploring the associations between changes in gut microbiota and the corresponding metabolites with neurodegeneration in the human brain have only begun to emerge more recently. Further, the findings of such studies are often difficult to translate into simple clinical applications that result in measurable health outcomes. The purpose of this paper is to appraise the literature on a select set of faecal biomarkers from a clinician’s perspective. This practical review aims to examine key physiological processes that influence both gastrointestinal, as well as brain health, and to discuss how tools such as the characterisation of commensal bacteria, the identification of potential opportunistic, pathogenic and parasitic organisms and the quantification of gut microbiome biomarkers and metabolites can help inform clinical decisions of nutrition and lifestyle medicine practitioners.

High Salt Cross-Protects Escherichia coli from Antibiotic Treatment through Increasing Efflux Pump Expression

Environmental stresses often co-occur when bacteria confront antibiotic treatment. We provide a clear example that a natural stress condition (high salt) can cross-protect bacteria from antibiotic treatment by triggering the bacterial stress response program (elevated AcrAB-TolC efflux pump expression). Our study highlights the importance of taking the co-occurrence of bacterial environmental stresses into consideration when investigating antibiotic susceptibility and applying antimicrobial treatment.

Environmental stresses often co-occur when bacteria encounter antibiotic treatment inside the human body. The cellular response to environmental stressors can alter the global gene expression pattern of bacteria. However, the relationship between the cellular stress response and antibiotic susceptibility remains poorly understood. Here we studied the effect of high salt, an important environmental stress condition inside the human body, on bacterial susceptibility to antibiotics. We found that high salt reduces the susceptibility of Escherichia coli to tetracycline and chloramphenicol, leading to a cross-protection effect. The cross-protection effect originates from the increased AcrAB-TolC efflux pump expression level under high-salt conditions. Our study demonstrates that stress-induced gene expression alterations can cross-protect bacteria from antibiotic treatment and should thus be considered when investigating antibiotic susceptibility and applying antimicrobial treatment.

IMPORTANCE Environmental stresses often co-occur when bacteria confront antibiotic treatment. We provide a clear example that a natural stress condition (high salt) can cross-protect bacteria from antibiotic treatment by triggering the bacterial stress response program (elevated AcrAB-TolC efflux pump expression). Our study highlights the importance of taking the co-occurrence of bacterial environmental stresses into consideration when investigating antibiotic susceptibility and applying antimicrobial treatment.

Potential Interplay between Hyperosmolarity and Inflammation on Retinal Pigmented Epithelium in Pathogenesis of Diabetic Retinopathy

Diabetic retinopathy is a frequent eyesight threatening complication of type 1 and type 2 diabetes. Under physiological conditions, the inner and the outer blood-retinal barriers protect the retina by regulating ion, protein, and water flux into and out of the retina. During diabetic retinopathy, many factors, including inflammation, contribute to the rupture of the inner and/or the outer blood-retinal barrier. This rupture leads the development of macular edema, a foremost cause of sight loss among diabetic patients. Under these conditions, it has been speculated that retinal pigmented epithelial cells, that constitute the outer blood-retinal barrier, may be subjected to hyperosmolar stress resulting from different mechanisms. Herein, we review the possible origins and consequences of hyperosmolar stress on retinal pigmented epithelial cells during diabetic retinopathy, with a special focus on the intimate interplay between inflammation and hyperosmolar stress, as well as the current and forthcoming new pharmacotherapies for the treatment of such condition.

The nutrition-gut microbiome-physiology axis and allergic diseases

Dietary and bacterial metabolites influence immune responses. This raises the question whether the increased incidence of allergies, asthma, some autoimmune diseases, cardiovascular disease, and others might relate to intake of unhealthy foods, and the decreased intake of dietary fiber. In recent years, new knowledge on the molecular mechanisms underpinning a 'diet-gut microbiota-physiology axis' has emerged to substantiate this idea. Fiber is fermented to short chain fatty acids (SCFAs), particularly acetate, butyrate, and propionate. These metabolites bind 'metabolite-sensing' G-protein-coupled receptors such as GPR43, GPR41, and GPR109A. These receptors play fundamental roles in the promotion of gut homeostasis and the regulation of inflammatory responses. For instance, these receptors and their metabolites influence Treg biology, epithelial integrity, gut homeostasis, DC biology, and IgA antibody responses. The SCFAs also influence gene transcription in many cells and tissues, through their inhibition of histone deacetylase expression or function. Contained in this mix is the gut microbiome, as commensal bacteria in the gut have the necessary enzymes to digest dietary fiber to SCFAs, and dysbiosis in the gut may affect the production of SCFAs and their distribution to tissues throughout the body. SCFAs can epigenetically modify DNA, and so may be one mechanism to account for diseases with a 'developmental origin', whereby in utero or post-natal exposure to environmental factors (such as nutrition of the mother) may account for disease later in life. If the nutrition-gut microbiome-physiology axis does underpin at least some of the Western lifestyle influence on asthma and allergies, then there is tremendous scope to correct this with healthy foodstuffs, probiotics, and prebiotics.

Increased salt exposure affects both lymphoid and myeloid effector functions, influencing innate-associated disease but not T-cell-associated autoimmunity

High salt consumption has since long been associated with elevated blood pressure and cardiovascular disease. Recently, mouse studies suggested that a high dietary salt intake exacerbates the clinical manifestations of autoimmunity. Using naïve cells ex vivo after pre-exposure of mice to high salt intake, we showed that increased salt exposure affects the viability and effector functions of immune cells. CD4+ T-cells evidenced a pro-inflammatory phenotype characterized by increased secretion of IFNγ and IL-17A, when exposed to high salt concentrations in vitro. Interestingly, this phenotype was associated with osmotic pressure, as replacing salt for d-mannitol resulted in similar observations. However, high salt intake did not alter the development of T-cell-dependent autoimmunity. Instead, recruitment of peritoneal macrophages was increased in mice pre-exposed to high salt concentrations. These cells had an increased production of both TNFα and IL-10, suggesting that salt stimulates expansion and differentiation of different subsets of macrophages. Moreover, mice pre-exposed to high salt intake developed exacerbated symptoms of colitis, when induced by dextran sulphate sodium. The aggravated colitis in salt-exposed animals was associated with a higher frequency of CD4+ T-cells and CD11b+ CD64+ macrophages producing TNFα. These phenotypes correlated with elevated titres of faecal IgA and higher lymphocytic cellularity in the colon, mesenteric lymph nodes and spleen. In conclusion, we report here that high salt intake affects both lymphoid and myeloid cells ex vivo. However, the effects of high salt intake in vivo seem less pronounced in terms of CD4+ T-cell responses, whereas macrophage-dependent pathologies are significantly influenced.

Interrelation of Diet, Gut Microbiome, and Autoantibody Production

B cells possess a predominant role in adaptive immune responses via antibody-dependent and -independent functions. The microbiome of the gastrointestinal tract is currently being intensively investigated due to its profound impact on various immune responses, including B cell maturation, activation, and IgA antibody responses. Recent findings have demonstrated the interplay between dietary components, gut microbiome, and autoantibody production. "Western" dietary patterns, such as high fat and high salt diets, can induce alterations in the gut microbiome that in turn affects IgA responses and the production of autoantibodies. This could contribute to multiple pathologies including autoimmune and inflammatory diseases. Here, we summarize current knowledge on the influence of various dietary components on B cell function and (auto)antibody production in relation to the gut microbiota, with a particular focus on the gut-brain axis in the pathogenesis of multiple sclerosis.

The role of the lipidome in obesity-mediated colon cancer risk

Obesity is a state of chronic inflammation influenced by lipids such as fatty acids and their secondary oxygenated metabolites deemed oxylipids. Many such lipid mediators serve as potent signaling molecules of inflammation, which can further alter lipid metabolism and lead to carcinogenesis. For example, sphingosine-1-phosphate activates cyclooxygenase-2 in endothelial cells resulting in the conversion of arachidonic acid (AA) to prostaglandin E₂ (PGE₂). PGE₂ promotes colon cancer cell growth. In contrast, the less studied path of AA oxygenation via cytochrome p450 enzymes produces epoxyeicosatetraenoic acids (EETs), whose anti-inflammatory properties cause shrinking of enlarged adipocytes, a characteristic of obesity, through the liberation of fatty acids. It is now thought that EET depletion occurs in obesity and may contribute to colon cell carcinogenesis. Meanwhile, gangliosides, a type of sphingolipid, are cell surface signaling molecules that contribute to the apoptosis of colon tumor cells. Many of these discoveries have been made recently and the mechanisms are still not fully understood, leading to an exciting new chapter of lipidomic research. In this review, mechanisms behind obesity-associated colon cancer are discussed with a focus on the role of small lipid signaling molecules in the process. Specifically, changes in lipid metabolite levels during obesity and the development of colon cancer, as well as novel biomarkers and targets for therapy, are discussed.

Symptom Management and Lifestyle Modifications in Multiple Sclerosis

PURPOSE OF REVIEW

This article reviews the rationale and approach to symptom management and lifestyle modifications in multiple sclerosis (MS).

RECENT FINDINGS

MS symptoms are important to treat because they affect quality of life and daily activity. Appreciation of cluster symptoms (where one symptom contributes to another), changes over time, and multimodality therapeutic approaches are guiding optimized symptom management. Equally important are lifestyle modifications that enhance central nervous system reserve and function. These modifications are the foundation for a health maintenance, wellness, and vascular risk factor control program.

SUMMARY

Symptom management and lifestyle modifications are important therapeutic targets to improve the lives of patients with MS.

From Infections to Anthropogenic Inflicted Pathologies: Involvement of Immune Balance

A temporal trend can be seen in recent human history where the dominant causes of death have shifted from infectious to chronic diseases in industrialized societies. Human influences in the current "Anthropocene" epoch are exponentially impacting the environment and consequentially health. Changing ecological niches are suggested to have created health transitions expressed as modifications of immune balance from infections inflicting pathologies in the Holocene epoch (12,000 years ago) to human behaviors inflicting pathologies beginning in the Anthropocene epoch (300 years ago). A review of human immune health and adaptations responding to environmental (biological, chemical, physical, and psychological) stresses, which are influenced by social conditions, emphasize the involvement of fluctuations in immune cell subsets affecting influential gene-environment interactions. The literature from a variety of fields (anthropological, immunological, and environmental) is incorporated to present an expanded perspective on shifts in diseases within the context of immune balance and function and environmental immunology. The influences between historical and contemporary human ecology are examined in relation to human immunity. Several examples of shifts in human physiology and immunity support the premise that increased incidences of chronic diseases are a consequence of human modification of environment and lifestyle. Although the development of better health care and a broader understanding of human health have helped with better life quality and expectancy, the transition of morbidity and mortality rates from infections to chronic diseases is a cause for concern. Combinations of environmental stressors/pollutants and human behaviors and conditions are modulating the immune-neuroendocrine network, which compromises health benefits.