The potential importance of the built-environment microbiome and its impact on human health

There is increasing evidence that interactions between microbes and their hosts not only play a role in determining health and disease but also in emotions, thought, and behavior. Built environments greatly influence microbiome exposures because of their built-in highly specific microbiomes coproduced with myriad metaorganisms including humans, pets, plants, rodents, and insects. Seemingly static built structures host complex ecologies of microorganisms that are only starting to be mapped. These microbial ecologies of built environments are directly and interdependently affected by social, spatial, and technological norms. Advances in technology have made these organisms visible and forced the scientific community and architects to rethink gene-environment and microbe interactions respectively. Thus, built environment design must consider the microbiome, and research involving host-microbiome interaction must consider the built-environment. This paradigm shift becomes increasingly important as evidence grows that contemporary built environments are steadily reducing the microbial diversity essential for human health, well-being, and resilience while accelerating the symptoms of human chronic diseases including environmental allergies, and other more life-altering diseases. New models of design are required to balance maximizing exposure to microbial diversity while minimizing exposure to human-associated diseases. Sustained trans-disciplinary research across time (evolutionary, historical, and generational) and space (cultural and geographical) is needed to develop experimental design protocols that address multigenerational multispecies health and health equity in built environments.

Effects of intermittent fasting on periodontal inflammation and subgingival microbiota

BACKGROUND

Studies on the impact of intermittent fasting on periodontal health are still scarce. Thus, this study evaluated the effects of long-term intermittent fasting on periodontal health and the subgingival microbiota.

METHODS

This pilot study was part of a nonrandomized controlled trial. Overweight/obese participants (n = 14) entered an intermittent fasting program, specifically the 5:2 diet, in which they restricted caloric intake to about a quarter of the normal total daily caloric expenditure for two nonconsecutive days/week. Subjects underwent a thorough clinical and laboratory examination, including an assessment of their periodontal condition, at baseline and 6 months after starting the diet. Additionally, subgingival microbiota was assessed by 16S rRNA gene sequencing.

RESULTS

After 6 months of intermittent fasting, weight, body mass index, C-reactive protein, hemoglobin A1c (HbA1c), and the cholesterol profile improved significantly (p < 0.05). Moreover, significant reductions were observed in bleeding on probing (p = 0.01) and the presence of shallow periodontal pockets after fasting (p < 0.001), while no significant change was seen in plaque index (p = 0.14). While we did not observe significant changes in α- or β-diversity of the subgingival microbiota related to dietary intervention (p > 0.05), significant differences were seen in the abundances of several taxa among individuals exhibiting ≥60% reduction (good responders) in probing pocket depth of 4-5 mm compared to those with <60% reduction (bad responders).

CONCLUSION

Intermittent fasting decreased systemic and periodontal inflammation. Although the subgingival microbiota was unaltered by this intervention, apparent taxonomic variability was observed between good and bad responders.

Microbial Indoles: Key Regulators of Organ Growth and Metabolic Function

Gut microbes supporting body growth are known but the mechanisms are less well documented. Using the microbial tryptophan metabolite indole, known to regulate prokaryotic cell division and metabolic stress conditions, we mono-colonized germ-free (GF) mice with indole-producing wild-type Escherichia coli (E. coli) or tryptophanase-encoding tnaA knockout mutant indole-non-producing E. coli. Indole mutant E. coli mice showed multiorgan growth retardation and lower levels of glycogen, cholesterol, triglycerides, and glucose, resulting in an energy deficiency despite increased food intake. Detailed analysis revealed a malfunctioning intestine, enlarged cecum, and reduced numbers of enterochromaffin cells, correlating with a metabolic phenotype consisting of impaired gut motility, diminished digestion, and lower energy harvest. Furthermore, indole mutant mice displayed reduction in serum levels of tricarboxylic acid (TCA) cycle intermediates and lipids. In stark contrast, a massive increase in serum melatonin was observed-frequently associated with accelerated oxidative stress and mitochondrial dysfunction. This observational report discloses functional roles of microbe-derived indoles regulating multiple organ functions and extends our previous report of indole-linked regulation of adult neurogenesis. Since indoles decline by age, these results imply a correlation with age-linked organ decline and levels of indoles. Interestingly, increased levels of indole-3-acetic acid, a known indole metabolite, have been shown to correlate with younger biological age, further supporting a link between biological age and levels of microbe-derived indole metabolites. The results presented in this resource paper will be useful for the future design of food intervention studies to reduce accelerated age-linked organ decline.

Nuanced contribution of gut microbiome in the early brain development of mice

The complex symbiotic relationship between the mammalian body and gut microbiome plays a critical role in the health outcomes of offspring later in life. The gut microbiome modulates virtually all physiological functions through direct or indirect interactions to maintain physiological homeostasis. Previous studies indicate a link between maternal/early-life gut microbiome, brain development, and behavioral outcomes relating to social cognition. Here we present direct evidence of the role of the gut microbiome in brain development. Through magnetic resonance imaging (MRI), we investigated the impact of the gut microbiome on brain organization and structure using germ-free (GF) mice and conventionalized mice, with the gut microbiome reintroduced after weaning. We found broad changes in brain volume in GF mice that persist despite the reintroduction of gut microbes at weaning. These data suggest a direct link between the maternal gut or early-postnatal microbe and their impact on brain developmental programming.

A tryptophan metabolite made by a gut microbiome eukaryote induces pro-inflammatory T cells

The large intestine harbors microorganisms playing unique roles in host physiology. The beneficial or detrimental outcome of host-microbiome coexistence depends largely on the balance between regulators and responder intestinal CD4+ T cells. We found that ulcerative colitis-like changes in the large intestine after infection with the protist Blastocystis ST7 in a mouse model are associated with reduction of anti-inflammatory Treg cells and simultaneous expansion of pro-inflammatory Th17 responders. These alterations in CD4+ T cells depended on the tryptophan metabolite indole-3-acetaldehyde (I3AA) produced by this single-cell eukaryote. I3AA reduced the Treg subset in vivo and iTreg development in vitro by modifying their sensing of TGFβ, concomitantly affecting recognition of self-flora antigens by conventional CD4+ T cells. Parasite-derived I3AA also induces over-exuberant TCR signaling, manifested by increased CD69 expression and downregulation of co-inhibitor PD-1. We have thus identified a new mechanism dictating CD4+ fate decisions. The findings thus shine a new light on the ability of the protist microbiome and tryptophan metabolites, derived from them or other sources, to modulate the adaptive immune compartment, particularly in the context of gut inflammatory disorders.

Evaluation of an individually tailored smoking-cessation intervention for patients with rheumatoid arthritis in an outpatient clinic

OBJECTIVE

The aim of this study was to evaluate an individually tailored smoking-cessation intervention delivered in rheumatology care and compare the characteristics of patients who quit smoking with those who did not.

METHOD

This was an open single-group prospective intervention study over 24 months, with assessments at baseline and at 6, 12, 18, and 24 months. Current smokers with rheumatoid arthritis (RA) were invited to a smoking-cessation programme including behavioural change support, with or without pharmacotherapy. Data on disease activity, medical treatment, and patient-reported outcomes were retrieved from the Swedish Rheumatology Quality Register. The primary outcome was the proportion of patients at month 24 who reported having quit smoking with self-reported 7 day smoking abstinence.

RESULTS

In total, 99 patients participated in the study. Median age was 58 years (interquartile range 50-64); 69% were female and 88% rheumatoid factor and/or anti-cyclic citrullinated peptide positive. At 24 months, 21% of the patients had quit smoking. At 6, 12, and 18 months, 12%, 12%, and 14% of patients, respectively, had quit smoking. For patients still smoking at 24 months, the median number of cigarettes per day was significantly reduced from 12 to 6 (p ≤ 0.001). Among patients who had quit smoking at 24 months, a smaller proportion reported anxiety at baseline compared to those still smoking (28% vs 58%, p = 0.02).

CONCLUSION

A smoking-cessation intervention including behavioural change support with or without pharmacotherapy can be helpful for a substantial number of RA patients. Anxiety is associated with lower smoking-cessation success rates.

When dysbiosis meets dystrophy: an unwanted gut-muscle connection

Duchenne muscular dystrophy (DMD) is a devastating neuromuscular degenerative disease with no known cure to date. In recent years, the hypothesis of a "gut-muscle axis" has emerged suggesting that bidirectional communication between the gut microbiota and the muscular system regulates the muscular function and may be perturbed in several muscular disorders. In addition, the excessive consumption of sugar and of lipid-rich processed food products are factors that further aggravate the phenotype for such diseases and accelerate biological aging. However, these unhealthy microbiota profiles can be reversed by individualized dietary changes to not only alter the microbiota composition but also to reset the production of microbial metabolites known to trigger beneficial effects typically associated with prolonged health span. Two recent studies (in this issue of EMBO Mol Med) highlight the interesting potential of microbiota-informed next-generation dietary intervention programs to be considered in genetically linked muscle disorders like DMD.

The link between neuroinflammation and the neurovascular unit in synucleinopathies

The neurovascular unit (NVU) is composed of vascular cells, glial cells, and neurons. As a fundamental functional module in the central nervous system, the NVU maintains homeostasis in the microenvironment and the integrity of the blood-brain barrier. Disruption of the NVU and interactions among its components are involved in the pathophysiology of synucleinopathies, which are characterized by the pathological accumulation of α-synuclein. Neuroinflammation contributes to the pathophysiology of synucleinopathies, including Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies. This review aims to summarize the neuroinflammatory response of glial cells and vascular cells in the NVU. We also review neuroinflammation in the context of the cross-talk between glial cells and vascular cells, between glial cells and pericytes, and between microglia and astroglia. Last, we discuss how α-synuclein affects neuroinflammation and how neuroinflammation influences the aggregation and spread of α-synuclein and analyze different properties of α-synuclein in synucleinopathies.

Gut microbiome profiling in systemic sclerosis: a metagenomic approach

OBJECTIVES

The early gastrointestinal (GI) manifestation of systemic sclerosis (SSc) suggests a possible GI microbiota engagement in the pathophysiology and/or progression of SSc. Previous studies have revealed dysbiosis among Caucasian SSc patients. This study extends these findings in Asian SSc patients.

METHODS

Adult SSc patients, stratified according to 1) on immunosuppressive (On-IS) drugs or 2) no immunosuppressive drugs (No-IS), and age-and-sex-matched healthy controls (HC) were recruited. Metagenomic sequencing of stool DNA was compared between SSc patients and HC, and between SSc (On-IS) and (No-IS) patients. Alpha and beta-diversity, taxonomic and functional profiling were evaluated.

RESULTS

Twenty-three female SSc patients (12 On-IS; 11 No-IS; 5 diffuse and 18 limited SSc subtype) and 19 female HC, with median age of 54 years and 56 years, respectively, were recruited. Median SSc disease duration was 3.3 years. Alpha diversity was significantly higher in SSc versus HC (p=0.014) and in SSc (No-IS) versus HC (p=0.006). There was no significant difference in beta diversity between SSc and HC (p=0.307). At the phyla level, there were significantly increased abundance of Firmicutes and Actinobacteria in SSc versus HC, and reduced abundance of Bacteroidetes (all p<0.001). At the species level, there were significantly increased abundance of several Lactobacillus, Bifidobacterium, and Coprococcus species in SSc, and increased abundance of Odoribacter, Bacteroides and Prevotella species in HC. KEGG pathway analysis demonstrated distinct differences between SSc vs HC, and between SSc (No-IS) and SSc (On-IS).

CONCLUSIONS

Using metagenomic sequencing, our study further underlines distinct alterations in microbiota profiling among Asian SScpatients.

Implicit satiety goals and food-related expectations predict portion size in older adults: Findings from the BAMMBE cohort

Portion size selection is an indicator of appetite and within younger adults, is predicted by factors such as expected satiety, liking and motivations to achieve an ideal sensation of fullness (i.e., implicit satiety goals). Currently, there is limited research available on the determinants of portion size selection within older adults. Therefore, the current study aimed to examine the relationship between individual differences in implicit satiety goals, food-related expectations, and portion size selection in older adults. Free-living older adult Singaporeans (N = 115; Nmales = 62; age: M = 66.21 years, SD = 4.78, range = 60-83 years) participated as part of the Brain, Ageing, Microbiome, Muscle, Bone, and Exercise Study (BAMMBE). Participants completed questionnaires on their subjective requirements for experiencing different states of satiety and food-related expectations (i.e., liking, how filling) as well as a computerised portion size selection task. Using a multiple regression, we found that goals to feel comfortably full (B = 3.08, SE = 1.04, t = 2.96, p = .004) and to stop hunger (B = -2.25, SE = 0.82, t = -2.75, p = .007) significantly predicted larger portion size selection (R2 = 0.24, F(4,87) = 6.74, p < .001). Larger portion sizes (R2 = 0.53, F(5,90) = 20.58, p < .001) were also predicted by greater expected satiety (B = 0.47, SE = 0.09, t = 5.15, p < .001) and lower perceptions of how filling foods are (B = -2.92, SE = 0.77, t = -3.79, p < .001) but not liking (B = -0.09, SE = 0.91, t = -0.10, p = .925) or frequency (B = -18.42, SE = 16.91, t = -1.09, p = .279) of consumption of target foods. Comparing our findings to results of studies conducted with younger adults suggests the influence of factors such as satiety related goals on portion size selection may change with ageing while the influence of other factors (e.g., expected satiety/fullness delivered by foods) may remain consistent. These findings may inform future strategies to increase/decrease portion size accordingly to ensure older adults maintain an appropriate healthy weight.

Diet-Associated Variability in the Elderly Gut Microbiome

Objectives

The gut microbiome adapts to diet variations, which contribute to interindividual variability in human host metabolism and environmental factors. Microbe-diet studies have largely focused on specific diets (e.g., high-fat Western, Mediterranean-style) in American and European populations, with limited studies on compositionally-different diets in Asian populations. This study aimed to understand how diet composition modulates the gut microbiome in a Singapore multi-ethnic population.

Methods

We performed metagenomic sequencing of faecal samples from 118 healthy individuals (66 ± 5 years old), and estimated their food and nutrient intakes from 3-day food records (IRB-2018–01-011). Multivariate associations between microbial composition (species) and functional potentials (pathways, enzymes) with diet variables were analysed using linear mixed models with Benjamin-Hochberg correction, and adjusted for age, sex, BMI, physical activity, energy intake and medications. Permutational multivariate analysis of variance, based on Bray-Curtis dissimilarity metric, was applied to quantify variance within the microbiome that is explained by diet variables.

Results

We found gut microbes (5 phyla, >100 species) significantly associated with one of four observed dietary patterns (P < 0.05), various food groups and nutrients (q < 0.1). The microbiome was driven by intake and diversity of plant-based foods. Parabacteroides and Blautia species, and microbial metabolism of energy, carbohydrate and glycan were associated with increased intakes of white rice and noodles. Prevotella species were associated with increased intakes of legumes, wholegrains and plant protein. Lachnospira, Clostridiumand Fournierella species, and microbial lipid metabolism were associated with energy-dense diet. Lastly, Firmicutes, Eubacterium, Ruminococcus and Roseburia species as well as microbial regulation of amino acid metabolism were associated with high-fibre diet.

Conclusions

This study provides new insights into gut microbial variations by distinct Asian dietary composition, supporting the feasibility of intervening habitual diets to reshape the gut microbiome for better health.

Funding Sources

This project was funded by LKC, CONIC and ARISE, NTU, and NTU-CSIRO Precision Health and Technologies Seed Fund.

POS1522-HPR COMPARISON OF EDUCATIONAL NEEDS AMONG PATIENTS WITH ANCA ASSOCIATED VASCULITIS AND SYSTEMIC LUPUS ERYTHEMATOSUS – A PILOT STUDY USING THE EDUCATIONAL NEEDS ASSESSMENT TOOL

Background

Patients with chronic disease need to learn and adapt to symptoms, treatment, and the impact of disease. Knowledge about the specific disease is one way to empower the patients to cope. We previously reported that disease duration and sex, rather than disease characteristics associate with an increased need of educational support in ANCA associated vasculitis (AAV) (1). Data on how specific educational needs vary between different inflammatory rheumatic diseases are lacking.

Objectives

The aim of the study was to compare educational needs among two chronic systemic inflammatory diseases, AAV and Systemic lupus erythematosus (SLE) using the Educational Needs Assessment Tool (ENAT).

Methods

This pilot study included cross-sectional data from two separate cohorts, AVV and SLE, from the Rheumatology clinic at Karolinska University Hospital in Sweden during 2009-2022. Inclusion criteria were minimum age of 18 years and literate in Swedish. Exclusion criterion was cognitive impairment interfering with literate capabilities.

Educational needs were captured by patients’ answers to the questionnaire ENAT. The ENAT consists of 39 questions, presented as total ENAT and seven domains (managing pain, movement, feelings, disease process, treatment, self-management and, support systems) each containing 4-7 items (from ’not at all important’ = 0, to ‘extremely important’ = 3). The participants’ responses were presented as “mean % of the domain score”, from 0 interpreted as no educational need to 100 as highest educational need. Participants with AAV and SLE respectively were individually matched for disease duration, sex, and education. For comparisons paired samples t-test were used.

Results

Twenty-two matched pairs (86% female), mean (SD) disease duration 5.7 (8) years, were included. The mean age were 43 (14.0) years for AAV 61 and (14.7) years for SLE (p=0.001). Educational length was reported as mean 14 (3.6) years among SLE patients and 13 (2.9) years among AAV patients (p=0.111).

In all patients, the mean total ENAT was 60.4% (range 23-100%) and did not differ between the two cohorts (p=0.2) (Table 1). In the pooled group the highest educational need was found in the domains ‘Disease process’ (mean 78.3%) and ‘Self-management’ (mean 75.9%). Lowest educational need was found in the domains ‘Movement’ (mean 46.7%) and ‘Managing pain’ (mean 51.6%).

Table 1.

Comparison of ENAT scores (mean % of max) (SD) between patient with SLE and AAV

ENAT domainAll n=44SLE n=22AAV n=22pManaging pain51.6 (29.8)50.8 (28.7)52.4 (32.2)0.867Movement46.7 (35.1)41.9 (34.2)49.2 (35.7)0.500Feelings63.1 (31.0)54.6 (30.6)70.4 (30.3)0.087Disease process78.3 (22.1)73.9 (23.0)83.4 (20.9)0.130Treatments60.7 (35.1)46.4 (36.0)74.2 (30.4)0.021Self-management75.9 (21.1)75.8 (18.8)76.9 (24.3)0.886Support systems54.0 (30.2)49.2 (31.4)58.7 (28.8)0.302Total ENAT60.4 (24.0)55.7 (22.8)65.0 (24.8)0.216

Patients with AAV report a higher educational need in total ENAT as well as in all individual domains, compared to SLE (Table 1), but only significantly in the domain ‘Treatments’ where the educational need among AAV was mean 74.2% (30.4) and for SLE mean 46.4% (SD 36.0) (p = 0.02).

Conclusion

In this pilot study with SLE and AAV, we found educational needs regarding ‘Treatments’ to be substantially increased among the participants with AAV, compared to SLE, despite that the participants were matched for disease duration and sex, two variables previously found to be indicators of increased educational needs. AAV patients with higher educational needs were older, this result needs to be further explored in a larger sample.

References

[1]Brolin S, Lövström B, et al. POS1476-HPR The need for information among patients with anca associated vasculitis differs between groups. Annals of the Rheumatic Diseases. 2021;80(Suppl 1):1023.

Acknowledgements

We are grateful to the participating patients, and colleagues assisting in the data collection.

Disclosure of Interests

None declared

Irritable bowel syndrome and risk of glaucoma: An analysis of two independent population-based cohort studies

OBJECTIVE

Irritable bowel syndrome (IBS) is a chronic disorder associated with an abnormal gastrointestinal microbiome. Microbiome-host interactions are known to influence organ function including in the central nervous system; thus, we sought to identify whether IBS may be a risk factor for the development of glaucoma.

DESIGN

Two prospective cohort studies.

SUBJECTS

The 1958 United Kingdom Birth Cohort (UKBC; 9091 individuals) and the Danish National Registry of Patients (DNRP; 62,541 individuals with IBS and 625,410 matched general population cohort members).

METHODS

In the UKBC, participants were surveyed throughout life (including at ages 42 and 50). The DNRP contains records of hospital-based contacts and prescription data from the national prescription database.

MAIN OUTCOME MEASURE

The main outcome measure was incidence of glaucoma. In the UKBC, incident glaucoma at age 50 (n = 48) was determined through comparison of survey responses at ages 42 and 50 years. In the DNRP, glaucoma was assessed by hospital diagnosis (n = 1510), glaucoma surgery (n = 582) and initiation of glaucoma medications (n = 1674).

RESULTS

In the UKBC, the odds ratio (OR) of developing glaucoma between ages 42 and 50 in persons with a chronic IBS diagnosis was increased [OR: 5.84, 95% confidence interval (CI): 2.26-15.13]. People with an IBS diagnosis in the DNRP had a hazard ratio (HR) of 1.35 for developing physician-diagnosed glaucoma (95% CI: 1.16-1.56), an HR of 1.35 for undergoing glaucoma surgery (95% CI: 1.06-1.70) and an HR of 1.19 for initiating glaucoma medication (95% CI: 1.03-1.38).

CONCLUSIONS

In two large European cohort studies, IBS is a risk factor for glaucoma.

Tryptophan-metabolizing gut microbes regulate adult neurogenesis via the aryl hydrocarbon receptor

While modulatory effects of gut microbes on neurological phenotypes have been reported, the mechanisms remain largely unknown. Here, we demonstrate that indole, a tryptophan metabolite produced by tryptophanase-expressing gut microbes, elicits neurogenic effects in the adult mouse hippocampus. Neurogenesis is reduced in germ-free (GF) mice and in GF mice monocolonized with a single-gene tnaA knockout (KO) mutant Escherichia coli unable to produce indole. External administration of systemic indole increases adult neurogenesis in the dentate gyrus in these mouse models and in specific pathogen-free (SPF) control mice. Indole-treated mice display elevated synaptic markers postsynaptic density protein 95 and synaptophysin, suggesting synaptic maturation effects in vivo. By contrast, neurogenesis is not induced by indole in aryl hydrocarbon receptor KO (AhR-/-) mice or in ex vivo neurospheres derived from them. Neural progenitor cells exposed to indole exit the cell cycle, terminally differentiate, and mature into neurons that display longer and more branched neurites. These effects are not observed with kynurenine, another AhR ligand. The indole-AhR-mediated signaling pathway elevated the expression of β-catenin, Neurog2, and VEGF-α genes, thus identifying a molecular pathway connecting gut microbiota composition and their metabolic function to neurogenesis in the adult hippocampus. Our data have implications for the understanding of mechanisms of brain aging and for potential next-generation therapeutic opportunities.

Incomplete Systemic Recovery and Metabolic Phenoreversion in Post-Acute-Phase Nonhospitalized COVID-19 Patients: Implications for Assessment of Post-Acute COVID-19 Syndrome

We present a multivariate metabotyping approach to assess the functional recovery of nonhospitalized COVID-19 patients and the possible biochemical sequelae of "Post-Acute COVID-19 Syndrome", colloquially known as long-COVID. Blood samples were taken from patients ca. 3 months after acute COVID-19 infection with further assessment of symptoms at 6 months. Some 57% of the patients had one or more persistent symptoms including respiratory-related symptoms like cough, dyspnea, and rhinorrhea or other nonrespiratory symptoms including chronic fatigue, anosmia, myalgia, or joint pain. Plasma samples were quantitatively analyzed for lipoproteins, glycoproteins, amino acids, biogenic amines, and tryptophan pathway intermediates using Nuclear Magnetic Resonance (NMR) spectroscopy and mass spectrometry. Metabolic data for the follow-up patients (n = 27) were compared with controls (n = 41) and hospitalized severe acute respiratory syndrome SARS-CoV-2 positive patients (n = 18, with multiple time-points). Univariate and multivariate statistics revealed variable patterns of functional recovery with many patients exhibiting residual COVID-19 biomarker signatures. Several parameters were persistently perturbed, e.g., elevated taurine (p = 3.6 × 10-3 versus controls) and reduced glutamine/glutamate ratio (p = 6.95 × 10-8 versus controls), indicative of possible liver and muscle damage and a high energy demand linked to more generalized tissue repair or immune function. Some parameters showed near-complete normalization, e.g., the plasma apolipoprotein B100/A1 ratio was similar to that of healthy controls but significantly lower (p = 4.2 × 10-3) than post-acute COVID-19 patients, reflecting partial reversion of the metabolic phenotype (phenoreversion) toward the healthy metabolic state. Plasma neopterin was normalized in all follow-up patients, indicative of a reduction in the adaptive immune activity that has been previously detected in active SARS-CoV-2 infection. Other systemic inflammatory biomarkers such as GlycA and the kynurenine/tryptophan ratio remained elevated in some, but not all, patients. Correlation analysis, principal component analysis (PCA), and orthogonal-partial least-squares discriminant analysis (O-PLS-DA) showed that the follow-up patients were, as a group, metabolically distinct from controls and partially comapped with the acute-phase patients. Significant systematic metabolic differences between asymptomatic and symptomatic follow-up patients were also observed for multiple metabolites. The overall metabolic variance of the symptomatic patients was significantly greater than that of nonsymptomatic patients for multiple parameters (χ2p = 0.014). Thus, asymptomatic follow-up patients including those with post-acute COVID-19 Syndrome displayed a spectrum of multiple persistent biochemical pathophysiology, suggesting that the metabolic phenotyping approach may be deployed for multisystem functional assessment of individual post-acute COVID-19 patients.

POS1476-HPR THE NEED FOR INFORMATION AMONG PATIENTS WITH ANCA ASSOCIATED VASCULITIS DIFFERS BETWEEN GROUPS

Background:

Being diagnosed with ANCA associated vasculitis (AAV) can be a frightening experience and means facing changes that involves adapting to new situations1. Patients that are provided adequate information are better equipped to make well informed decisions regarding their care and stay compliant to the treatment plan. In order to provide adequate patient-centered information at the appropriate time and to identify those who may need extra support, the information needs must be explored2. There have been several studies on the information needs of rheumatological patients, although very few studies for patients with AAV.

Objectives:

The aim of this study was to explore what information patients with AAV need from their rheumatological team and how it differs between groups (gender, disease duration).

Methods:

Men and women over 18 years were included through a consecutive sample from a Rheumatology or Nephrology Clinic at Karolinska University Hospital in Sweden during 2008-2019. Patients with all forms of AAV (GPA, MPA and EGPA), that had the Rheumatology clinic as primary contact, were included.

The participants were given Educational Needs Assessment Tool (ENAT) that measures the patient’s information needs3. The initial question, ‘Do you need information right now about something that can help you with your rheumatic disease?’ is answered yes/no. ENAT then includes 7 domains (Managing pain, Movement, Feelings, Disease process, Treatments, Self-help measures and Support systems) each containing 4-7 items (4-point Likert scale, ’not at all important = 0’ to ‘extremely important = 3’). The total sum is divided by the maximum score and gives the percentage response of maximum score (0-100%), 0% meaning no information need and 100% highest information need. The responses are presented as “mean % of the domain score”. Independent-sample t-test was used to compare the mean between groups. One way ANOVA was used to compare the mean domain score between the different diagnoses and age groups.

Results:

178 individuals completed the questionnaire, equally divided by gender. Age ranged from 18-85, median 61. 33,7% had been diagnosed within 2 years.

The mean total score was 56,8 % of the highest possible score (0-100%). The highest information need was found in the domains ‘Disease process’ (78,1%), ‘Self-help measures’ (68,5%) and ‘Treatments’ (63,6%) whereas lesser need for information was found in the domains ‘Managing pain’ (47,5%), ‘Support systems’ (46,5%) and ‘Movement’ (41,1%). The domain ‘Feelings’ was scored as moderate (55,5%).

Those who acknowledge a present information need also scored significantly higher overall in all the domains. Disease duration and gender showed significantly affect the information need. Highest scores were found among women with a disease duration < 2 years with significant difference in 3/7 domains. Age, disease activity, diagnosis and social status did not affect the ENAT scores.

Conclusion:

Even though only 38% of participants stated a current need for information, the results indicate that there are certain areas that patients with AAV consider important to receive more information about. Special consideration needs to be taken to women with short disease duration since they were shown to have a significantly higher need for information.

References:

[1]Mooney, J., et al. (2013). ‘In one ear and out the other - it’s a lot to take in’: a qualitative study exploring the informational needs of patients with ANCA-associated vasculitis. Musculoskeletal Care, 11(1)

[2]Ntatsaki, E., et al. (2014). BSR and BHPR guideline for the management of adults with ANCA-associated vasculitis. Rheumatology (Oxford), 53(12)

[3]Hardware, B., et al. (2004). Towards the development of a tool to assess educational needs in patients with arthritis. Clinical Effectiveness in Nursing, 8(2)

Disclosure of Interests:

None declared

OP0156-HPR THE EFFECT OF A PERSON-CENTERED SMOKING CESSATION PROGRAM IN RHEUMATOID ARTHRITIS PATIENTS IN A RHEUMATOLOGY OUTPATIENT CLINIC SETTING – RESULTS OF AN INTERVENTIONAL FEASIBILITY STUDY

Background:

Smoking is associated with worse treatment response1 and higher mortality2 in rheumatoid arthritis (RA).

Objectives:

To assess the effect of a smoking cessation intervention in a rheumatology setting.

Methods:

We designed a smoking cessation interventional feasibility study. RA patients who were active smokers were asked to participate. A nurse-delivered program consisting of behavioural changes techniques and voluntary pharmacotherapy was executed. The intervention was at baseline and at several time points during a 24 month period, based on the individual patient’s needs. Smoking status was collected at baseline, 6, 12, 18 and 24 months. Smoking cessation was verified by 7-days abstinence and carbon monoxide in expiratory air. The main outcome was the proportion of patients who quit smoking (QS) at 24 months.

Results:

A total of 99 patients were included in the study between 2011-2020. Median (IQR) age of patients was 58 (50 - 64), 69 % were female and 82% were RF and/or ACPA positive. 59% of patients had a newly diagnosed RA, (included from the early RA-track), with a median (IQR) symptom duration of 5 (2-9,5) months. Patients with established RA 41% (included from regular rheumatology department) had a median disease duration of 4 (2-8) years. After 24 months 21% quit smoking (QS) (Table 1). At months 6, 12, 18 and 24 the proportion of QS patients was 12, 13, 15 and 21, respectively. The proportion of QS patients at month 12 and continued being in the QS group throughout the study period was 10%. In the subgroup of patients who continued smoking (CS) the median number of cigarettes per day was significantly reduced at all follow-up time points (Table 1). No significant differences were observed at baseline between CS at 24 months and QS, apart from the proportion of patients who reported anxiety (extracted from EQ-5D and defined as absent or present), which was significantly fewer in the QS group (Table). In the QS group at month 24, the proportion of females was numerically lower compared to CS (52% vs. 73%, p=0.07).

Table 1.

Baseline demographical, clinical characteristics and number of cigarettes at specific time-points for patients who were non-smokers (QS) and smokers (CS) at month 24.

QSN=21 (21%)CSN=78 (79%)Difference between QS and CS(p-value)Age*(median, IQR)60 (53-62)57 (50-64)0.94Symptom duration in early RA patients (months) (median, IQR)6 (2-12)4.5 (2-8.5)0.49Disease duration of patients with established RA (years) (median, IQR)8 (3.5-16.5)3 (2-6)0.12% females52730.07% RF and/or ACPA positive85810.70DAS28* (median, IQR)4.24 (3.13-5.72)4.11 (2.88-5.36)0.69HAQ* (median, IQR)0.75 (0.25 -1.38)0.88 (0.38-1.25)0.74VAS pain* (median, IQR)46.0 (11-60)34.5 (12-70)0.90% of patients with reported anxiety* (part of EQ5D)28580.02Smoking duration (years)(median, IQR)40 (30-50)40 (34-49)0.92Median number of cigarettes per day-at baseline10 (7-15)12 (10-20)0.22-at 6 months0 (0-3)6 (3-10)0.006-at 12 months0 (0-5)6 (3-10)0.0003-at 18 months0 (0-0)6 (2-10)0.00-at 24 months0 (0-0)6 (3-10)0.00

*=measured at baseline

Conclusion:

Smoking cessation intervention in a rheumatology clinic setting may facilitate reduced smoking or complete cessation in patients with RA. Patient who did not report anxiety were more likely to quit smoking.

References:

[1]Saevarsdottir, S., et al (2011). Patients with early rheumatoid arthritis who smoke are less likely to respond to treatment with methotrexate and tumor necrosis factor inhibitors: observations from the Epidemiological Investigation of Rheumatoid Arthritis and the Swedish Rheumatology Register cohorts. Arthritis Rheum, 63(1), 26-36.

[2]Joseph, R´., et al (2016) Smoking-Related Mortality in Patients With Early Rheumatoid Arthritis: A Retrospective Cohort Study Using the Clinical Practice Research Datalink Arthritis Care Res (Hoboken) 68 (11) 1598-1606

Acknowledgements:

This study was partly funded by grants from Swedish Reumatism Association.

Disclosure of Interests:

Marie-Louise Karlsson Speakers bureau: MLK has recivied fee form Novartis Sverige AB, Grant/research support from: MLK had recivied finical grants from Novartis Sverige. Abbvie has fincial support brochure wich was used in the study, Katarina Hertzberg-Nyquist: None declared, Saedis Saevarsdottir Employee of: S is a part-time employee of deCODE genetics Inc., unrelated to this work., Ingrid E. Lundberg Consultant of: I Lundberg har recieved consulting fees from Corbus Pharmaceutical, EMD Serono Research & Development Institute, Octapharma AG, Orphazyme, Janssen, Kezar Life Sciences Inc., Ingrid Demmelmaie: None declared, Susanne Pettersson: None declared, Katerina Chatzidionysiou Consultant of: KC has received consultancy fees from Eli Lilly, AbbVie and Pfizer.

Systemic Perturbations in Amine and Kynurenine Metabolism Associated with Acute SARS-CoV-2 Infection and Inflammatory Cytokine Responses

We performed quantitative metabolic phenotyping of blood plasma in parallel with cytokine/chemokine analysis from participants who were either SARS-CoV-2 (+) (n = 10) or SARS-CoV-2 (-) (n = 49). SARS-CoV-2 positivity was associated with a unique metabolic phenotype and demonstrated a complex systemic response to infection, including severe perturbations in amino acid and kynurenine metabolic pathways. Nine metabolites were elevated in plasma and strongly associated with infection (quinolinic acid, glutamic acid, nicotinic acid, aspartic acid, neopterin, kynurenine, phenylalanine, 3-hydroxykynurenine, and taurine; p < 0.05), while four metabolites were lower in infection (tryptophan, histidine, indole-3-acetic acid, and citrulline; p < 0.05). This signature supports a systemic metabolic phenoconversion following infection, indicating possible neurotoxicity and neurological disruption (elevations of 3-hydroxykynurenine and quinolinic acid) and liver dysfunction (reduction in Fischer's ratio and elevation of taurine). Finally, we report correlations between the key metabolite changes observed in the disease with concentrations of proinflammatory cytokines and chemokines showing strong immunometabolic disorder in response to SARS-CoV-2 infection.

Regional Diets Targeting Gut Microbial Dynamics to Support Prolonged Healthspan

In the last 150 years, we have seen a significant increase in average life expectancy, associated with a shift from infectious to non-communicable diseases. The rising incidence of these diseases, for which age is often the largest risk factor, highlights the need for contemporary societies to improve healthy ageing for their growing silver generations. As ageing is an inevitable, non-reversing and highly individualised process, we need to better understand how non-genetic factors like diet choices and commensal gut microbes can modulate the biology of ageing. In this review, we discuss how geographical and ethnic variations influence habitual dietary patterns, nutrient structure, and gut microbial profiles with potential impact on the human healthspan. Several gut microbial genera have been associated with healthy elderly populations but are highly variable across populations. It seems unlikely that a universal pro-longevity gut microbiome exists. Rather, the optimal microbiome appears to be conditional on the microbial functionality acting on regional- and ethnicity-specific trends driven by cultural food context. We also highlight dietary and microbial factors that have been observed to elicit individual and clustered biological responses. Finally, we identify next generation avenues to modify otherwise fixed host functions and the individual ageing trajectory by manipulating the malleable gut microbiome with regionally adapted, personalised food intervention regimens targeted at prolonging human healthspan.

The role of gut dysbiosis in Parkinson's disease: mechanistic insights andtherapeutic options

Parkinson's disease is a common neurodegenerative disease in which gastrointestinal symptoms may appear prior to motor symptoms. The gut microbiota of patients with Parkinson's disease shows unique changes, which may be used as early biomarkers of disease. Alteration in gut microbiota composition may be related to the cause or effect of motor or non-motor symptoms, but the specific pathogenic mechanisms are unclear. The gut microbiota and its metabolites have been suggested to be involved in the pathogenesis of Parkinson's disease by regulating neuroinflammation, barrier function and neurotransmitter activity. There is bidirectional communication between the enteric nervous system and the central nervous system, and the microbiota-gut-brain axis may provide a pathway for the transmission of α-synuclein. We highlight recent discoveries and alterations of the gut microbiota in Parkinson's disease, and highlight current mechanistic insights on the microbiota-gut-brain axis in disease pathophysiology. We discuss the interactions between production and transmission of α-synuclein and gut inflammation and neuroinflammation. In addition, we also draw attention to diet modification, use of probiotics and prebiotics and fecal microbiota transplantation as potential therapeutic approaches that may lead to a new treatment paradigm for Parkinson's disease.

The hygiene hypothesis, the COVID pandemic, and consequences for the human microbiome

The COVID-19 pandemic has the potential to affect the human microbiome in infected and uninfected individuals, having a substantial impact on human health over the long term. This pandemic intersects with a decades-long decline in microbial diversity and ancestral microbes due to hygiene, antibiotics, and urban living (the hygiene hypothesis). High-risk groups succumbing to COVID-19 include those with preexisting conditions, such as diabetes and obesity, which are also associated with microbiome abnormalities. Current pandemic control measures and practices will have broad, uneven, and potentially long-term effects for the human microbiome across the planet, given the implementation of physical separation, extensive hygiene, travel barriers, and other measures that influence overall microbial loss and inability for reinoculation. Although much remains uncertain or unknown about the virus and its consequences, implementing pandemic control practices could significantly affect the microbiome. In this Perspective, we explore many facets of COVID-19-induced societal changes and their possible effects on the microbiome, and discuss current and future challenges regarding the interplay between this pandemic and the microbiome. Recent recognition of the microbiome's influence on human health makes it critical to consider both how the microbiome, shaped by biosocial processes, affects susceptibility to the coronavirus and, conversely, how COVID-19 disease and prevention measures may affect the microbiome. This knowledge may prove key in prevention and treatment, and long-term biological and social outcomes of this pandemic.

The gut microbiota influences skeletal muscle mass and function in mice

The functional interactions between the gut microbiota and the host are important for host physiology, homeostasis, and sustained health. We compared the skeletal muscle of germ-free mice that lacked a gut microbiota to the skeletal muscle of pathogen-free mice that had a gut microbiota. Compared to pathogen-free mouse skeletal muscle, germ-free mouse skeletal muscle showed atrophy, decreased expression of insulin-like growth factor 1, and reduced transcription of genes associated with skeletal muscle growth and mitochondrial function. Nuclear magnetic resonance spectrometry analysis of skeletal muscle, liver, and serum from germ-free mice revealed multiple changes in the amounts of amino acids, including glycine and alanine, compared to pathogen-free mice. Germ-free mice also showed reduced serum choline, the precursor of acetylcholine, the key neurotransmitter that signals between muscle and nerve at neuromuscular junctions. Reduced expression of genes encoding Rapsyn and Lrp4, two proteins important for neuromuscular junction assembly and function, was also observed in skeletal muscle from germ-free mice compared to pathogen-free mice. Transplanting the gut microbiota from pathogen-free mice into germ-free mice resulted in an increase in skeletal muscle mass, a reduction in muscle atrophy markers, improved oxidative metabolic capacity of the muscle, and elevated expression of the neuromuscular junction assembly genes Rapsyn and Lrp4 Treating germ-free mice with short-chain fatty acids (microbial metabolites) partly reversed skeletal muscle impairments. Our results suggest a role for the gut microbiota in regulating skeletal muscle mass and function in mice.

FRI0168 ASSOCIATION OF OVERWEIGHT/OBESITY WITH IMPAIRED HEALTH-RELATED QUALITY OF LIFE IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Patients with systemic lupus erythematosus (SLE) experience a considerably impaired health-related quality of life (HRQoL) compared with the general population. Previous literature has implied an association between high body mass index (BMI) and HRQoL diminutions. However, data are scarce and further exploration in large study populations and, importantly, with regard to the clinical significance of this association is needed.

Objectives:

The aim of this study was to determine whether overweight and/or obesity were associated with impaired physical and/or mental HRQoL aspects in the SLE population of two large clinical trials.

Methods:

We utilised pooled baseline data from the BLISS-52 (NCT00424476) and BLISS-76 (NCT00410384) clinical trials of belimumab (N=1684). Access to data was granted by GlaxoSmithKline. The patients were stratified into four groups based on their body mass index (BMI), according to WHO guidelines. We conducted comparisons between non-overweight versus overweight, and non-obese versus obese SLE patients. HRQoL was self-reported using the Medical Outcomes Study (MOS) short form 36 (SF-36) health survey, the functional assessment of chronic illness therapy (FACIT)-Fatigue scale and the three-level EuroQol- 5 Dimension (EQ-5D) questionnaire. We explored whether the differences in scores were clinically meaningful using previously determined thresholds for minimal clinically important differences (MCIDs). The non-parametric Mann-Whitney U test was used for comparisons between different BMI groups. Linear regression analysis was next applied to test independence in multivariable models, adjusting for age, sex, ethnicity, disease duration, disease activity, organ damage and standard of care treatment.

Results:

Forty-four per cent (44%) of the patients had a BMI score over the normal range, and 18% were obese. The overweight group performed worse than the non-overweight with regard to FACIT-Fatigue scores (mean ± standard deviation: 27.7 ± 12.1 vs 32.0 ± 11.3; P<0.001), EQ-5D score (0.70 ± 0.19 vs 0.76 ± 0.18; P<0.001) and all SF-36 subscales and component summaries. The differences were greater than the MCIDs for physical component summary (PCS) scores (36.9 ± 9.3 vs 40.8 ± 9.6; P<0.001), physical functioning (53.3 ± 25.1 vs 63.6 ± 25-1; P<0.001), role physical (48.0 ± 27.1 vs 55.6 ± 26.9; P<0.001), bodily pain (43.8 ± 22.4 vs 52.5 ± 25.1; P<0.001), vitality (39.6 ± 21.7 vs 46.6 ± 21.3; P<0.001), and social functioning scores (55.8 ± 25.2 vs 62.6 ± 25.2; P<0.001). Likewise, obese patients reported worse FACIT-Fatigue scores (25.7 ± 11.9 vs 31.1 ± 11.6; P<0.001), EQ-5D scores (0.68 ± 0.20 vs 0.75 ± 0.18; P<0.001) and clinically important diminutions of HRQoL in all SF-36 items, except for the mental component summary (MCS), role emotional and mental health.

In multivariable linear regression analysis, the overweight and obese group showed worse PCS scores (standardised coefficient: β=-0.09; P<0.001 and β=-0.13; P<0.001, respectively) and FACIT-Fatigue scores (β=-0.11; P<0.001 and β=-0.10; P<0.001, respectively), and overweight patients had significantly impaired MCS scores (β=-0.05; P=0.039), irrespective of other factors. High disease activity and organ damage were associated with impaired HRQoL in all aspects, while Asian patients reported better PCS scores (and β=0.29; P=0.007) and FACIT-Fatigue scores (β=0.33; P=0.002).

Conclusion:

BMI above normal was highly associated with HRQoL impairment, especially in physical aspects. Further survey to examine causality is warranted to support structured weight control strategies as an intervention towards a more favourable HRQoL.

Disclosure of Interests:

None declared

Microbial Metabolites and Intestinal Stem Cells Tune Intestinal Homeostasis

Microorganisms that colonize the gastrointestinal tract, collectively known as the gut microbiota, are known to produce small molecules and metabolites that significantly contribute to host intestinal development, functions, and homeostasis. Emerging insights from microbiome research reveal that gut microbiota-derived signals and molecules influence another key player maintaining intestinal homeostasis-the intestinal stem cell niche, which regulates epithelial self-renewal. In this review, the literature on gut microbiota-host crosstalk is surveyed, highlighting the effects of gut microbial metabolites on intestinal stem cells. The production of various classes of metabolites, their actions on intestinal stem cells are discussed and, finally, how the production and function of metabolites are modulated by aging and dietary intake is commented upon.

Reprint of: Manipulation of microbiota reveals altered callosal myelination and white matter plasticity in a model of Huntington disease

Structural and molecular myelination deficits represent early pathological features of Huntington disease (HD). Recent evidence from germ-free (GF) animals suggests a role for microbiota-gut-brain bidirectional communication in the regulation of myelination. In this study, we aimed to investigate the impact of microbiota on myelin plasticity and oligodendroglial population dynamics in the mixed-sex BACHD mouse model of HD. Ultrastructural analysis of myelin in the corpus callosum revealed alterations of myelin thickness in BACHD GF compared to specific-pathogen free (SPF) mice, whereas no differences were observed between wild-type (WT) groups. In contrast, myelin compaction was altered in all groups when compared to WT SPF animals. Levels of myelin-related proteins were generally reduced, and the number of mature oligodendrocytes was decreased in the prefrontal cortex under GF compared to SPF conditions, regardless of genotype. Minor differences in commensal bacteria at the family and genera levels were found in the gut microbiota of BACHD and WT animals housed in standard living conditions. Our findings indicate complex effects of a germ-free status on myelin-related characteristics, and highlight the adaptive properties of myelination as a result of environmental manipulation.

Neurogenesis and prolongevity signaling in young germ-free mice transplanted with the gut microbiota of old mice

The gut microbiota evolves as the host ages, yet the effects of these microbial changes on host physiology and energy homeostasis are poorly understood. To investigate these potential effects, we transplanted the gut microbiota of old or young mice into young germ-free recipient mice. Both groups showed similar weight gain and skeletal muscle mass, but germ-free mice receiving a gut microbiota transplant from old donor mice unexpectedly showed increased neurogenesis in the hippocampus of the brain and increased intestinal growth. Metagenomic analysis revealed age-sensitive enrichment in butyrate-producing microbes in young germ-free mice transplanted with the gut microbiota of old donor mice. The higher concentration of gut microbiota–derived butyrate in these young transplanted mice was associated with an increase in the pleiotropic and prolongevity hormone fibroblast growth factor 21 (FGF21). An increase in FGF21 correlated with increased AMPK and SIRT-1 activation and reduced mTOR signaling. Young germ-free mice treated with exogenous sodium butyrate recapitulated the prolongevity phenotype observed in young germ-free mice receiving a gut microbiota transplant from old donor mice. These results suggest that gut microbiota transplants from aged hosts conferred beneficial effects in responsive young recipients.

Persistent changes in liver methylation and microbiome composition following reversal of diet-induced non-alcoholic-fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a metabolic liver disease that is thought to be reversible by changing the diet. To examine the impact of dietary changes on progression and cure of NAFLD, we fed mice a high-fat diet (HFD) or high-fructose diet (HFrD) for 9 weeks, followed by an additional 9 weeks, where mice were given normal chow diet. As predicted, the diet-induced NAFLD elicited changes in glucose tolerance, serum cholesterol, and triglyceride levels in both diet groups. Moreover, the diet-induced NAFLD phenotype was reversed, as measured by the recovery of glucose intolerance and high cholesterol levels when mice were given normal chow diet. However, surprisingly, the elevated serum triglyceride levels persisted. Metagenomic analysis revealed dietary-induced changes of microbiome composition, some of which remained altered even after reversing the diet to normal chow, as illustrated by species of the Odoribacter genus. Genome-wide DNA methylation analysis revealed a "priming effect" through changes in DNA methylation in key liver genes. For example, the lipid-regulating gene Apoa4 remained hypomethylated in both groups even after introduction to normal chow diet. Our results support that dietary change, in part, reverses the NAFLD phenotype. However, some diet-induced effects remain, such as changes in microbiome composition, elevated serum triglyceride levels, and hypomethylation of key liver genes. While the results are correlative in nature, it is tempting to speculate that the dietary-induced changes in microbiome composition may in part contribute to the persistent epigenetic modifications in the liver.

Gut microbes, ageing & organ function: a chameleon in modern biology?

All species, including humans, are cohabited by a myriad of microbial species, which massively influences body function in a diet‐, exercise‐ and age‐dependent manner. The microbiome composition differs between individuals, partly due to the polymorphic immune system, as well as the environment, making the microbe–host interplay unique in each one of us. Ageing is a gradual loss of function in part due to reduced repair mechanisms and accumulation of tissue damage through mechanisms largely unknown. Accumulating evidence suggests that our indigenous microbes, a known major regulator of human physiology, are also connected to regulate the ageing process through signalling pathways and metabolites though the biological mechanisms are unknown. At an ageing meeting in Singapore in 2018, investigators discussed the current understanding of microbe regulation and its impact on healthy ageing. This review summarizes the highlights from the meeting and conveys some of the new ideas that emerged around gut microbes and the biology of ageing. While highly speculative, an idea emerged in which gut microbes constantly respond and evolve to environmental cues, as part of an ageing process, thus serving as a second messenger to support and attenuate organ decline in a diet‐, gender‐ and age‐dependent manner.

ILSI Southeast Asia Region conference proceedings: The gut, its microbes and health: relevance for Asia

BACKGROUND AND OBJECTIVES

The human being is a complex entity, involving interaction between microbes and the human host. Evidence shows that the nutritional value of food is influenced in part by the structure and operations of an individual's gut microbial community, and food in turn shapes the individual's microbiome. A conference was held to promote understanding of the intestinal microbiome and its implications for health and disease, particularly among Asian populations.

METHODS AND STUDY DESIGN

Papers describing 1) the intestinal ecosystem in Asian populations, 2) changes in intestinal microbiota through life and its effects, 3) the Asian gut microbiota in disease conditions, 4) indigenous probiotics to maintain a healthy gut microbiota, 5) probiotic regulation in an Asian country, and 6) the results of a panel discussion are included in this report.

CONCLUSIONS

The gut microbial inhabitants of Asian people differ from those of Europe and North America. Geographic location, diet, and ethnic background influence intestinal microbial composition. Urbanization and economic development have brought changes in traditional Asian diets, which in turn affected the gut microbiome, contributing to a shift in the region's health burden from infectious diseases to non-communicable chronic diseases. Novel probiotic strains of Indonesian origin demonstrated significant enhancement of humoral immune response in human studies. Knowledge gaps and implications for research to further understand the Asian gut microbiome were discussed.

The Microbiome Mediates Environmental Effects on Aging

Humans' indigenous microbes strongly influence organ functions in an age- and diet-dependent manner, adding an important dimension to aging biology that remains poorly understood. Although age-related differences in the gut microbiota composition correlate with age-related loss of organ function and diseases, including inflammation and frailty, variation exists among the elderly, especially centenarians and people living in areas of extreme longevity. Studies using short-lived as well as nonsenescent model organisms provide surprising functional insights into factors affecting aging and implicate attenuating effects of microbes as well as a crucial role for certain transcription factors like forkhead box O. The unexpected beneficial effects of microbes on aged animals imply an even more complex interplay between the gut microbiome and the host. The microbiome constitutes the major interface between humans and the environment, is influenced by biosocial stressors and behaviors, and mediates effects on health and aging processes, while being moderated by sex and developmental stages.

A double-blind randomized placebo-controlled trial of probiotics in systemic sclerosis associated gastrointestinal disease

OBJECTIVE

Assess whether treatment with probiotics improve gastrointestinal symptoms in patients with systemic sclerosis (SSc).

METHODS

In this double-blind randomized placebo-controlled parallel-group phase II trial, SSc subjects with total score ≥ 0.1 on a validated SSc-specific gastrointestinal tract (GIT) questionnaire were randomized (1:1) to receive 60 days of high dose multi-strain probiotics (Vivomixx® 1800 billion units/day) or identical placebo, followed by an additional 60 days of probiotics in both groups. Between group differences in GIT score change were assessed after 60 days (primary outcome, time-point T1) and 120 days (secondary outcome, time-point, T2) by an intention-to-treat approach. Stool samples at three time-points were subjected to 16S next generation sequencing.

RESULTS

Forty subjects were randomized to placebo-probiotics (n = 21) or probiotics-probiotics (n = 19). At T1, no significant improvement was observed between the two groups, reported as mean ± SE for total GIT score (placebo 0.14 ± 0.06 versus probiotics 0.13 ± 0.07; p = 0.85) or its subdomains. At T2, whilst there was no significant improvement in total GIT score (placebo-probiotics -0.05±0.06; probiotics-probiotics -0.18 ± 0.07; p = 0.14), there was significant improvement of GIT-reflux in the probiotic group (-0.22 ± 0.05 versus placebo-probiotics 0.05 ± 0.07; p = 0.004). Subjects on probiotics exhibited increasing stool microbiota alpha diversity compared to the placebo-probiotics group. Adverse events (AEs) were mild, with similar proportion of subjects with AEs and serious AEs in both groups.

CONCLUSION

Whilst there was no clear improvement in overall GI symptoms after 60 days, we observed significantly improved GI reflux after 120 days of probiotics. The trial confirmed safety of multi-strain probiotics in SSc patients.

TRIAL REGISTRATION

Clinicaltrials.gov; NCT01804959.

Constitutive and inducible in vivo protein-DNA interactions at the tumor necrosis factor-alpha promoter in primary human T lymphocytes

Tumor necrosis factor-alpha (TNF-alpha) is a key cytokine of lymphocytes with major regulatory functions in immunomodulation, chronic inflammation, and septic shock. However, only limited information on TNF promoter regulation in vivo in primary lymphocytes is available. To determine and compare protein-DNA interactions at the native TNF locus in primary lymphocytes, we analyzed the human TNF-alpha promoter by ligation-mediated polymerase chain reaction (LM-PCR) techniques. Accordingly, primary CD4+ T lymphocytes from peripheral blood were cultured in the presence of various stimuli and analyzed by LM-PCR. Inducible in vivo protein-DNA interactions at the TNF promoter were detected between -120 and -70 bp of the human TNF promoter relative to the transcriptional start site. This area includes binding sites for transcription factors such as ETS-1, NFAT, ATF-2/c-jun, SP-1/Egr-1, and NF-kappaB. In contrast, no protein-DNA interactions were observed at various binding sites with reported regulatory function in tumor cell lines such as the k2 element, the NFAT site at -160, the AP1 site at -50, and the SP1 site at -65. Additional mutagenesis and transfection studies demonstrated that NF-kappaB and CREB/AP-1 are important regulators of inducible TNF promoter activity in primary human T lymphocytes. These results provide novel insights into the complex regulation of TNF gene transcription in primary T lymphocytes in vivo by constitutive and inducible protein-DNA interactions that appear to be at least partially different compared to previously characterized tumor cell lines.

Our Gut Microbiome: The Evolving Inner Self

The "holobiont" concept, defined as the collective contribution of the eukaryotic and prokaryotic counterparts to the multicellular organism, introduces a complex definition of individuality enabling a new comprehensive view of human evolution and personalized characteristics. Here, we provide snapshots of the evolving microbial-host associations and relations during distinct milestones across the lifespan of a human being. We discuss the current knowledge of biological symbiosis between the microbiome and its host and portray the challenges in understanding these interactions and their potential effects on human physiology, including microbiome-nervous system inter-relationship and its relevance to human variation and individuality.

Microbiome Influences Prenatal and Adult Microglia in a Sex-Specific Manner

Microglia are embryonically seeded macrophages that contribute to brain development, homeostasis, and pathologies. It is thus essential to decipher how microglial properties are temporally regulated by intrinsic and extrinsic factors, such as sexual identity and the microbiome. Here, we found that microglia undergo differentiation phases, discernable by transcriptomic signatures and chromatin accessibility landscapes, which can diverge in adult males and females. Remarkably, the absence of microbiome in germ-free mice had a time and sexually dimorphic impact both prenatally and postnatally: microglia were more profoundly perturbed in male embryos and female adults. Antibiotic treatment of adult mice triggered sexually biased microglial responses revealing both acute and long-term effects of microbiota depletion. Finally, human fetal microglia exhibited significant overlap with the murine transcriptomic signature. Our study shows that microglia respond to environmental challenges in a sex- and time-dependent manner from prenatal stages, with major implications for our understanding of microglial contributions to health and disease.

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Microglia undergo sequential phases of differentiation during development

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The maternal microbiome influences microglial properties during prenatal stages

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The absence of the microbiome has a sex- and time-specific impact on microglia

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Microbiome depletions have acute and long-term effects on microglial properties

Quantum changes in Helicobacter pylori gene expression accompany host-adaptation

Helicobacter pylori is a highly successful gastric pathogen. High genomic plasticity allows its adaptation to changing host environments. Complete genomes of H. pylori clinical isolate UM032 and its mice-adapted serial derivatives 298 and 299, generated using both PacBio RS and Illumina MiSeq sequencing technologies, were compared to identify novel elements responsible for host-adaptation. The acquisition of a jhp0562-like allele, which encodes for a galactosyltransferase, was identified in the mice-adapted strains. Our analysis implies a new β-1,4-galactosyltransferase role for this enzyme, essential for Le^y antigen expression. Intragenomic recombination between babA and babB genes was also observed. Further, we expanded on the list of candidate genes whose expression patterns have been mediated by upstream homopolymer-length alterations to facilitate host adaption. Importantly, greater than four-fold reduction of mRNA levels was demonstrated in five genes. Among the down-regulated genes, three encode for outer membrane proteins, including BabA, BabB and HopD. As expected, a substantial reduction in BabA protein abundance was detected in mice-adapted strains 298 and 299 via Western analysis. Our results suggest that the expression of Le^y antigen and reduced outer membrane protein expressions may facilitate H. pylori colonisation of mouse gastric epithelium.

A comparison of patients' and physicians' assessments of disease activity using the Swedish version of the Systemic Lupus Activity Questionnaire

OBJECTIVES

We compared patients' assessments of systemic lupus erythematosus (SLE) disease activity by a Swedish version of the Systemic Lupus Activity Questionnaire (SLAQ) with physicians' assessments by the Systemic Lupus Activity Measure (SLAM) and Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2K). We also explored the performance of the SLAQ in patients with short (< 1 year) versus long (≥ 1 year) disease duration.

METHOD

Patients filled out the SLAQ before physicians' assessments. Correlations between SLAQ total, subscales (Symptom score, Flares, Patients global) and SLAM and SLEDAI-2K, as well as between the corresponding items in SLAQ and SLAM, were evaluated using Spearman's ρ. Comparisons between patients with different disease durations were performed with Mann-Whitney U or chi-squared tests.

RESULTS

We included 203 patients (79% women), with a median age of 45 years [interquartile range (IQR) 33-57 years] and disease duration of 5 years (IQR 0-14 years). Correlations between physicians' SLAM without laboratory items (SLAM-nolab) and patients' assessments were: SLAQ total, ρ = 0.685, Symptom score, ρ = 0.651, Flares, ρ = 0.547, and Patients global, ρ = 0.600. Of the symptom items, fatigue (ρ = 0.640), seizures (ρ = 0.635), and headache (ρ = 0.604) correlated most closely. Neurology/stroke syndrome, skin, and lymphadenopathy correlated less well (ρ < 0.24). Patients' and physicians' assessments were notably more discordant for patients with short disease durations.

CONCLUSION

We confirm that the SLAQ can be used to monitor disease activity. However, the discrepancy between patients' and physicians' assessments was greater for patients with short versus long disease duration. We encourage further use of the SLAQ, but would like to develop a shorter version which would be valuable in modern, partly web-based, clinical care.

Host-microbiome interactions: the aryl hydrocarbon receptor and the central nervous system

The microbiome located within a given host and its organs forms a holobiont, an intimate functional entity with evolutionarily designed interactions to support nutritional intake and reproduction. Thus, all organs in a holobiont respond to changes within the microbiome. The development and function of the central nervous system and its homeostatic mechanisms are no exception and are also subject to regulation by the gut microbiome. In order for the holobiont to function effectively, the microbiome and host must communicate. The aryl hydrocarbon receptor is an evolutionarily conserved receptor recognizing environmental compounds, including a number of ligands produced directly and indirectly by the microbiome. This review focuses on the microbiome-gut-brain axis in regard to the aryl hydrocarbon receptor signaling pathway and its impact on underlying mechanisms in neurodegeneration.

Computed Tomography after Percutaneous Renal Stone Extraction

Eighty patients were examined with computed tomography (CT) of the kidney and the retroperitoneal space after percutaneous stone extraction. Most examinations were done within a week after the operation. The morphologic changes were usually small or none. In 7 patients minor renal or perirenal fluid collections were found. Their operations had been complicated by bleeding or leakage. In 66 patients CT was compared with conventional radiographs. Residual stones were more often detected by CT. They were usually small. Percutaneous renal stone extraction is considered a safe and efficient method.

Physical therapists' assessments, analyses and use of behavior change techniques in initial consultations on musculoskeletal pain: direct observations in primary health care

Background

Behavioral medicine (BM) treatment is recommended to be implemented for pain management in physical therapy. Its implementation requires physical therapists (PTs), who are skilled at performing functional behavioral analyses based on physical, psychological and behavioral assessments. The purpose of the current study was to explore and describe PTs’ assessments, analyses and their use of behavioral change techniques (BCTs) in initial consultations with patients who seek primary health care due to musculoskeletal pain.

Methods

A descriptive and explorative research design was applied, using data from video recordings of 12 primary health care PTs. A deductive analysis was performed, based on a specific protocol with definitions of PTs’ assessment of physical and psychological prognostic factors (red and yellow flags, respectively), analysis of the clinical problem, and use of BCTs. An additional inductive analysis was performed to identify and describe the variation in the PTs’ clinical practice.

Results

Red and yellow flags were assessed in a majority of the cases. Analyses were mainly based on biomedical assessments and none of the PTs performed functional behavioral analyses. All of the PTs used BCTs, mainly instruction and information, to facilitate physical activity and improved posture. The four most clinically relevant cases were selected to illustrate the variation in the PTs’ clinical practice. The results are based on 12 experienced primary health care PTs in Sweden, limiting the generalizability to similar populations and settings.

Conclusion

Red and yellow flags were assessed by PTs in the current study, but their interpretation and integration of the findings in analyses and treatment were incomplete, indicating a need of further strategies to implement behavioral medicine in Swedish primary health care physical therapy.

Helicobacter pylori and gut microbiota modulate energy homeostasis prior to inducing histopathological changes in mice

Helicobacter pylori have been shown to influence physiological regulation of metabolic hormones involved in food intake, energy expenditure and body mass. It has been proposed that inducing H. pylori-induced gastric atrophy damages hormone-producing endocrine cells localized in gastric mucosal layers and therefore alter their concentrations. In a recent study, we provided additional proof in mice under controlled conditions that H. pylori and gut microbiota indeed affects circulating metabolic gut hormones and energy homeostasis. In this addendum, we presented data from follow-up investigations that demonstrated H. pylori and gut microbiota-associated modulation of metabolic gut hormones was independent and precedes H. pylori-induced histopathological changes in the gut of H. pylori-infected mice. Thus, H. pylori-associated argumentation of energy homeostasis is not caused by injury to endocrine cells in gastric mucosa.

The gut microbiota keeps enteric glial cells on the move; prospective roles of the gut epithelium and immune system

The enteric nervous system (ENS) coordinates the major functions of the gastrointestinal tract. Its development takes place within a constantly changing environment which, after birth, culminates in the establishment of a complex gut microbiota. How such changes affect ENS development and its subsequent function throughout life is an emerging field of study that holds great interest but which is inadequately explored thus far. In this addendum, we discuss our recent findings showing that a component of the ENS, the enteric glial cell network that resides in the gut lamina propria, develops after birth and parallels the evolution of the gut microbiota. Importantly, this network was found to be malleable throughout life by incorporating new cells that arrive from the area of the gut wall in a process of directional movement which was controlled by the lumen gut microbiota. Finally, we postulate on the roles of the intestinal epithelium and the immune system as potential intermediaries between gut microbiota and ENS responses.

The gut microbiota influences blood-brain barrier permeability in mice

Pivotal to brain development and function is an intact blood-brain barrier (BBB), which acts as a gatekeeper to control the passage and exchange of molecules and nutrients between the circulatory system and the brain parenchyma. The BBB also ensures homeostasis of the central nervous system (CNS). We report that germ-free mice, beginning with intrauterine life, displayed increased BBB permeability compared to pathogen-free mice with a normal gut flora. The increased BBB permeability was maintained in germ-free mice after birth and during adulthood and was associated with reduced expression of the tight junction proteins occludin and claudin-5, which are known to regulate barrier function in endothelial tissues. Exposure of germ-free adult mice to a pathogen-free gut microbiota decreased BBB permeability and up-regulated the expression of tight junction proteins. Our results suggest that gut microbiota-BBB communication is initiated during gestation and propagated throughout life.