The Brain-Gut-Microbiome Axis.

Preclinical and clinical studies have shown bidirectional interactions within the brain-gut-microbiome axis. Gut microbes communicate to the central nervous system through at least 3 parallel and interacting channels involving nervous, endocrine, and immune signaling mechanisms. The brain can affect the community structure and function of the gut microbiota through the autonomic nervous system, by modulating regional gut motility, intestinal transit and secretion, and gut permeability, and potentially through the luminal secretion of hormones that directly modulate microbial gene expression. A systems biological model is proposed that posits circular communication loops amid the brain, gut, and gut microbiome, and in which perturbation at any level can propagate dysregulation throughout the circuit. A series of largely preclinical observations implicates alterations in brain-gut-microbiome communication in the pathogenesis and pathophysiology of irritable bowel syndrome, obesity, and several psychiatric and neurologic disorders. Continued research holds the promise of identifying novel therapeutic targets and developing treatment strategies to address some of the most debilitating, costly, and poorly understood diseases

The association between chronic disease and work productivity among public health staff in Kota Bharu district

Work productivity of public health staff is as much as crucial as other production labor force to ensure the empowerment of healthy nation, healthy human capitals thus contribute to high economic growth of our country since they are involved in promotion of healthy lifestyle, control and prevention of communicable and noncommunicable diseases. The objective of this study was to determine the proportion of chronic diseases and its association with work productivity among public health staff in Kota Bharu District. This is a cross sectional study done among 363 public health staffs using pro forma checklist which consist of socio-demographic data, status of chronic diseases, annual and medical leaves data and measuring presenteeism level using Stanford Presenteeism Scale questionnaire. The study showed the prevalence of dyslipidemia was 19.3%, hypertension 16.0%, asthma 12.7%, diabetes mellitus 11.6% and arthritis 5.0%. About 70% of staffs reported to have low work productivity for the past one year. There were 89% of staffs reported with high presenteeism, 62.5% absenteeism, and 1.4% with high sickness absence. Multiple logistic regression analysis showed that dyslipidemia (AOR 11.86, 95% CI: 2.76, 50.50; p = 0.001), hypertension (AOR 3.43, 95% CI: 1.13, 10.35; p = 0.029) and diabetes mellitus (AOR 5.40, 95% CI: 1.54, 18.99; p = 0.009) were significantly associated with low work productivity. However, there was no significant association was found between asthma, arthritis and other chronic diseases with low work productivity. This study demonstrated that chronic diseases can contribute to low work productivity affecting the quality of public health program

Chronic Early-life Stress in Rat Pups Alters Basal Corticosterone, Intestinal Permeability, and Fecal Microbiota at Weaning: Influence of Sex.

Background/aimsWistar rat dams exposed to limited nesting stress (LNS) from post-natal days (PND) 2 to 10 display erratic maternal behavior, and their pups show delayed maturation of the hypothalamic-pituitary-adrenal axis and impaired epithelial barrier at PND10 and a visceral hypersensitivity at adulthood. Little is known about the impact of early life stress on the offspring before adulthood and the influence of sex. We investigated whether male and female rats previously exposed to LNS displays at weaning altered corticosterone, intestinal permeability, and microbiota.MethodsWistar rat dams and litters were maintained from PND2 to 10 with limited nesting/bedding materials and thereafter reverted to normal housing up to weaning (PND21). Control litters had normal housing. At weaning, we monitored body weight, corticosterone plasma levels (enzyme immunoassay), in vivo intestinal to colon permeability (fluorescein isothiocyanate-dextran 4 kDa) and fecal microbiota (DNA extraction and amplification of the V4 region of the 16S ribosomal RNA gene).ResultsAt weaning, LNS pups had hypercorticosteronemia and enhanced intestinal permeability with females > males while body weights were similar. LNS decreased fecal microbial diversity and induced a distinct composition characterized by increased abundance of Gram positive cocci and reduction of fiber-degrading, butyrate-producing, and mucus-resident microbes.ConclusionsThese data indicate that chronic exposure to LNS during the first week post-natally has sustained effects monitored at weaning including hypercorticosteronemia, a leaky gut, and dysbiosis. These alterations may impact on the susceptibility to develop visceral hypersensitivity in adult rats and have relevance to the development of irritable bowel syndrome in childhood

Functional Somatic Syndromes: Emerging Biomedical Models and Traditional Chinese Medicine

The so-called functional somatic syndromes comprise a group of disorders that are primarily symptom-based, multisystemic in presentation and probably involve alterations in mind-brain-body interactions. The emerging neurobiological models of allostasis/allostatic load and of the emotional motor system show striking similarities with concepts used by Traditional Chinese Medicine (TCM) to understand the functional somatic disorders and their underlying pathogenesis. These models incorporate a macroscopic perspective, accounting for the toll of acute and chronic traumas, physical and emotional stressors and the complex interactions between the mind, brain and body. The convergence of these biomedical models with the ancient paradigm of TCM may provide a new insight into scientifically verifiable diagnostic and therapeutic approaches for these common disorders

Do upper leg compression garments aid performance and reduce exercise-induced muscle damage in recreational marathon runners?

Background: Despite the lack of scientific knowledge on the physiological and biomechanical effects of wearing compression garments (CGs), there has been an increase in the use of compression garments (CG) amongst endurance runners. Objectives: To compare marathon race performance, post-race pain, and mid-thigh circumference in marathon runners using upper leg CGs, with runners who did not use CGs in the same marathon race. Methods: The study was conducted on healthy, long-distance runners (n=18) participating in the Winelands Marathon race, Cape Town, South Africa. The CG group (n=10) participated in the race wearing upper leg CGs, while the control group (n=8) did not. Participants were tested on three occasions for various subjective markers of exercise-induced muscle damage (Visual analogue scale (VAS) pain rating score, and Likert scale for muscle pain), mid-thigh circumference for muscle swelling, and running performance (race pace). Results: VAS pain ratings for hamstring (p=0.04), knee flexion (p=0.02) and hip extension (p=0.04) were significantly lower than the ratings of the control group immediately post-race and two days post-race. No statistically significant differences were detected in race performance, mid-thigh circumferences or Likert scale for determination of muscle soreness. Discussion: Wearing of upper leg CGs while running a marathon race improved VAS pain ratings immediately post race through to two days post-race. However, due to no placebo control, this beneficial effect may be psychological as opposed to a physiological effect of the CGs on muscle pain. Conclusion: The use of upper leg CGs reduced subjective muscle pain in runners in the first 48 hours post-race.

Alterations in prefrontal-limbic functional activation and connectivity in chronic stress-induced visceral hyperalgesia.

Repeated water avoidance stress (WAS) induces sustained visceral hyperalgesia (VH) in rats measured as enhanced visceromotor response to colorectal distension (CRD). This model incorporates two characteristic features of human irritable bowel syndrome (IBS), VH and a prominent role of stress in the onset and exacerbation of IBS symptoms. Little is known regarding central mechanisms underlying the stress-induced VH. Here, we applied an autoradiographic perfusion method to map regional and network-level neural correlates of VH. Adult male rats were exposed to WAS or sham treatment for 1 hour/day for 10 days. The visceromotor response was measured before and after the treatment. Cerebral blood flow (CBF) mapping was performed by intravenous injection of radiotracer ([(14)C]-iodoantipyrine) while the rat was receiving a 60-mmHg CRD or no distension. Regional CBF-related tissue radioactivity was quantified in autoradiographic images of brain slices and analyzed in 3-dimensionally reconstructed brains with statistical parametric mapping. Compared to sham rats, stressed rats showed VH in association with greater CRD-evoked activation in the insular cortex, amygdala, and hypothalamus, but reduced activation in the prelimbic area (PrL) of prefrontal cortex. We constrained results of seed correlation analysis by known structural connectivity of the PrL to generate structurally linked functional connectivity (SLFC) of the PrL. Dramatic differences in the SLFC of PrL were noted between stressed and sham rats under distension. In particular, sham rats showed negative correlation between the PrL and amygdala, which was absent in stressed rats. The altered pattern of functional brain activation is in general agreement with that observed in IBS patients in human brain imaging studies, providing further support for the face and construct validity of the WAS model for IBS. The absence of prefrontal cortex-amygdala anticorrelation in stressed rats is consistent with the notion that impaired corticolimbic modulation acts as a central mechanism underlying stress-induced VH

Changes in training activity post COVID-19 infection in recreational runners and cyclists

Background: Anecdotal evidence suggests that athletes struggle to return to exercise post COVID-19 infection. However, studies evaluating the effect of COVID-19 on athletes’ exercise activity are limited. Objectives: The objectives of this study were: (i) to describe the perceptions of recreational runners and cyclists recovering from COVID-19 on their training activity and general wellbeing, (ii) to compare device-measured training data in runners and cyclists pre- and post COVID-19, with noninfected controls that had a training interruption. Methods: Participants who were recruited via social media completed an online questionnaire (n=61), including demographic, health and COVID-19 descriptive data. In a sub-sample, device-measured training data (heart rate, time, distance and speed, n=27) were obtained from GPS devices for four weeks before infection and on resumption of training. Similar data were collected for the control group (n=9) whose training had been interrupted but by factors excluding COVID-19. Results: Most participants experienced a mild to moderate illness (91%) that was associated with a training interruption time of two-four weeks. Decreases in heart rate, relative exercise intensity, speed, time and distance were observed during the first week of returning to training for both groups, followed by an increase from Week two onwards. Discussion: Results failed to support a ‘COVID-19 effect’ on exercise activity as reductions in training variables occurred in both the COVID-19 and control groups. A possible explanation for the reductions observed is a deliberate gradual return to training by athletes post-COVID-19. Conclusion: More research is needed using device-measured training data prior to and post COVID-19 infection to better understand the impact of the SARS-CoV-2 virus on the exercise activity of athletes.

Role of brain imaging in disorders of brain-gut interaction: a Rome Working Team Report.

Imaging of the living human brain is a powerful tool to probe the interactions between brain, gut and microbiome in health and in disorders of brain-gut interactions, in particular IBS. While altered signals from the viscera contribute to clinical symptoms, the brain integrates these interoceptive signals with emotional, cognitive and memory related inputs in a non-linear fashion to produce symptoms. Tremendous progress has occurred in the development of new imaging techniques that look at structural, functional and metabolic properties of brain regions and networks. Standardisation in image acquisition and advances in computational approaches has made it possible to study large data sets of imaging studies, identify network properties and integrate them with non-imaging data. These approaches are beginning to generate brain signatures in IBS that share some features with those obtained in other often overlapping chronic pain disorders such as urological pelvic pain syndromes and vulvodynia, suggesting shared mechanisms. Despite this progress, the identification of preclinical vulnerability factors and outcome predictors has been slow. To overcome current obstacles, the creation of consortia and the generation of standardised multisite repositories for brain imaging and metadata from multisite studies are required