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Persistent fatigue following SARS-CoV-2 infection is common and independent of severity of initial infection.
Townsend, L, Dyer, AH, Jones, K, Dunne, J, Mooney, A, Gaffney, F, O'Connor, L, Leavy, D, O'Brien, K, Dowds, J, et al
PloS one. 2020;15(11):e0240784
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Tiredness is a common symptom of Covid-19; however, it is unknown if this fatigue persists once recovered. This observational study of 128 recovered Covid-19 patients aimed to determine if fatigue persisted after recovery and whether severity of disease could predict fatigue. The results showed that post Covid-19 fatigue was reported in more than half of the participants and was particularly pronounced in females and in those with depression. Severity of disease did not predict fatigue. It was concluded that fatigue appears to outlast infection and fatigue was independent of disease severity. This study could be used by health care practitioners to understand that fatigue is common even after recovery from Covid-19 infection and women and sufferers of depression are the most susceptible.
Abstract
Fatigue is a common symptom in those presenting with symptomatic COVID-19 infection. However, it is unknown if COVID-19 results in persistent fatigue in those recovered from acute infection. We examined the prevalence of fatigue in individuals recovered from the acute phase of COVID-19 illness using the Chalder Fatigue Score (CFQ-11). We further examined potential predictors of fatigue following COVID-19 infection, evaluating indicators of COVID-19 severity, markers of peripheral immune activation and circulating pro-inflammatory cytokines. Of 128 participants (49.5 ± 15 years; 54% female), more than half reported persistent fatigue (67/128; 52.3%) at median of 10 weeks after initial COVID-19 symptoms. There was no association between COVID-19 severity (need for inpatient admission, supplemental oxygen or critical care) and fatigue following COVID-19. Additionally, there was no association between routine laboratory markers of inflammation and cell turnover (leukocyte, neutrophil or lymphocyte counts, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, C-reactive protein) or pro-inflammatory molecules (IL-6 or sCD25) and fatigue post COVID-19. Female gender and those with a pre-existing diagnosis of depression/anxiety were over-represented in those with fatigue. Our findings demonstrate a significant burden of post-viral fatigue in individuals with previous SARS-CoV-2 infection after the acute phase of COVID-19 illness. This study highlights the importance of assessing those recovering from COVID-19 for symptoms of severe fatigue, irrespective of severity of initial illness, and may identify a group worthy of further study and early intervention.
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Harnessing the immune system to overcome cytokine storm and reduce viral load in COVID-19: a review of the phases of illness and therapeutic agents.
Khadke, S, Ahmed, N, Ahmed, N, Ratts, R, Raju, S, Gallogly, M, de Lima, M, Sohail, MR
Virology journal. 2020;17(1):154
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Severe manifestations of COVID-19 infection and mortality are associated with a cytokine storm. This is an excessive inflammatory response to the infection leading to an overproduction of pro-inflammatory signalling molecules, which consequently contributes to tissue and organ damage. This literature review summarised current knowledge, as of June 2020, about virus-associated cytokine storm, virus-host interactions and immunological mechanism, to gain a better understanding of the phenomena observed in COVID-19 infections and devise better treatment strategies. The review briefly outlines the epidemiology of COVID-19, predictors of severity of disease, mode of transmission, testing, viral structure, mechanism of invasion of the host cell, replication and immune invasion and the progression of the four stages of the cytokine storm. The second part of the review discusses antiviral therapeutics of interest with a table summarising drugs, mechanism and available data. This article may be of interest to those who like to delve further into the mechanisms and immune components involved in a cytokine storm and gain an oversight of the pathways targeted by allopathic agents that have been put forward as treatment options.
Abstract
BACKGROUND Coronavirus disease 2019 (COVID-19) is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2, previously named 2019-nCov), a novel coronavirus that emerged in China in December 2019 and was declared a global pandemic by World Health Organization by March 11th, 2020. Severe manifestations of COVID-19 are caused by a combination of direct tissue injury by viral replication and associated cytokine storm resulting in progressive organ damage. DISCUSSION We reviewed published literature between January 1st, 2000 and June 30th, 2020, excluding articles focusing on pediatric or obstetric population, with a focus on virus-host interactions and immunological mechanisms responsible for virus associated cytokine release syndrome (CRS). COVID-19 illness encompasses three main phases. In phase 1, SARS-CoV-2 binds with angiotensin converting enzyme (ACE)2 receptor on alveolar macrophages and epithelial cells, triggering toll like receptor (TLR) mediated nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ƙB) signaling. It effectively blunts an early (IFN) response allowing unchecked viral replication. Phase 2 is characterized by hypoxia and innate immunity mediated pneumocyte damage as well as capillary leak. Some patients further progress to phase 3 characterized by cytokine storm with worsening respiratory symptoms, persistent fever, and hemodynamic instability. Important cytokines involved in this phase are interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α. This is typically followed by a recovery phase with production of antibodies against the virus. We summarize published data regarding virus-host interactions, key immunological mechanisms responsible for virus-associated CRS, and potential opportunities for therapeutic interventions. CONCLUSION Evidence regarding SARS-CoV-2 epidemiology and pathogenesis is rapidly evolving. A better understanding of the pathophysiology and immune system dysregulation associated with CRS and acute respiratory distress syndrome in severe COVID-19 is imperative to identify novel drug targets and other therapeutic interventions.
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Brown Adipose Crosstalk in Tissue Plasticity and Human Metabolism.
Scheele, C, Wolfrum, C
Endocrine reviews. 2020;41(1)
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Brown adipose tissue (BAT) is an important contributor to the regulation of metabolism via cellular communication with organs such as liver, muscle, gut and central nervous system. BAT is important for heat generation and is at high levels in human infants. Levels of activation of BAT decline as we age and it has been shown that the amount of BAT is smaller and its activity reduced in those with obesity and type 2 diabetes. To date, there is no answer to efficiently restore functional BAT in aging and obese subjects. This review looks at experiments done on the factors secreted from active BAT (batokines). The review aims to provide a structure for the processes and cell types involved in BAT and the recent findings of BAT whole-body communication are discussed. Altogether, these findings demonstrate that BAT has an adaptive capacity. Studying batokines, offers an alternative approach to identify novel drug targets for metabolic regulation.
Abstract
Infants rely on brown adipose tissue (BAT) as a primary source of thermogenesis. In some adult humans, residuals of brown adipose tissue are adjacent to the central nervous system and acute activation increases metabolic rate. Brown adipose tissue (BAT) recruitment occurs during cold acclimation and includes secretion of factors, known as batokines, which target several different cell types within BAT, and promote adipogenesis, angiogenesis, immune cell interactions, and neurite outgrowth. All these processes seem to act in concert to promote an adapted BAT. Recent studies have also provided exciting data on whole body metabolic regulation with a broad spectrum of mechanisms involving BAT crosstalk with liver, skeletal muscle, and gut as well as the central nervous system. These widespread interactions might reflect the property of BAT of switching between an active thermogenic state where energy is highly consumed and drained from the circulation, and the passive thermoneutral state, where energy consumption is turned off. (Endocrine Reviews 41: XXX - XXX, 2020).
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COVID-19 infection: the perspectives on immune responses.
Shi, Y, Wang, Y, Shao, C, Huang, J, Gan, J, Huang, X, Bucci, E, Piacentini, M, Ippolito, G, Melino, G
Cell death and differentiation. 2020;27(5):1451-1454
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The SARS-CoV-2 infection triggers an immune response which varies greatly from one person to another. It can be roughly divided into three stages: stage I, an asymptomatic incubation period with or without detectable virus; stage II, non-severe symptomatic period with the presence of virus; stage III, severe respiratory symptomatic stage with high viral load. Currently around 15% of people infected end up in severe stage III. There appears to be a two-phase immune response; an early protective phase and a second inflammation-driven damaging phase. In phase one the adaptive immune system responds to the virus. Being in good general health is important in this phase to limiting the progression of the disease to a more severe stage. In phase two the innate immune system response to tissue damage caused by the virus could lead to widespread inflammation of the lungs and acute respiratory distress syndrome or respiratory failure. Therapeutically this raises the question of whether the immune response should be boosted in phase one and suppressed in phase two. There also appears to be an element of viral relapse in some patients discharged from hospital indicating that a virus-eliminating immune response may be difficult to achieve naturally. These same patients may also not respond to vaccines. Overall, it is still unclear why some people develop severe disease, whilst others do not. Overall immunity alone does not explain the differences in disease presentation.
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'The long tail of Covid-19' - The detection of a prolonged inflammatory response after a SARS-CoV-2 infection in asymptomatic and mildly affected patients.
Doykov, I, Hällqvist, J, Gilmour, KC, Grandjean, L, Mills, K, Heywood, WE
F1000Research. 2020;9:1349
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‘Long COVID’ or the persistence of symptoms after SARS-CoV-2 infection, such as fatigue, is becoming increasingly common. As the emergence of the virus is still relatively recent in research terms, little is known about the long-term impact of the viruses infection. This study sought to generate further insights into the management and diagnostic of long COVID, by assessing a range of inflammatory markers from blood serum samples. Examined were 10 samples of health care workers with previous asymptomatic or moderate SARS-CoV-2 infections, compared to 10 samples of SARS-CoV-2 naive health care workers. The serum was analyzed by mass spectrometry using a customized panel of the 96 immune response associated proteins. Despite being mild to moderate cases, the results showed that even 40-60 days after infection, significant disturbance in the immune systems inflammatory response could be observed. Particularly markers that reflect anti-inflammatory pathways and mitochondrial stress. The study highlighted six of the most noteworthy proteins and included a brief description of their role. The authors suggest that analysing proteins by using targeted proteomic technology, could serve as a cost-effective strategy to further investigate the changes in inflammatory responses post SARS-CoV-2 infection. Which could help to aid the identification of potential treatment targets in the future. Relevant findings from this small study for clinical practice are that even mild to moderate SARS-CoV-2 infection can alter the inflammatory responses for months afterwards.
Abstract
'Long Covid', or medical complications associated with post SARS-CoV-2 infection, is a significant post-viral complication that is being more and more commonly reported in patients. Therefore, there is an increasing need to understand the disease mechanisms, identify drug targets and inflammatory processes associated with a SARS-CoV-2 infection. To address this need, we created a targeted mass spectrometry based multiplexed panel of 96 immune response associated proteins. We applied the multiplex assay to a cohort of serum samples from asymptomatic and moderately affected patients. All patients had tested positive for a SARS-CoV-2 infection by PCR and were determined to be subsequently positive for antibodies. Even 40-60 days post-viral infection, we observed a significant remaining inflammatory response in all patients. Proteins that were still affected were associated with the anti-inflammatory response and mitochondrial stress. This indicates that biochemical and inflammatory pathways within the body can remain perturbed long after SARS-CoV-2 infections have subsided even in asymptomatic and moderately affected patients.
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Borrelia burgdorferi peptidoglycan is a persistent antigen in patients with Lyme arthritis.
Jutras, BL, Lochhead, RB, Kloos, ZA, Biboy, J, Strle, K, Booth, CJ, Govers, SK, Gray, J, Schumann, P, Vollmer, W, et al
Proceedings of the National Academy of Sciences of the United States of America. 2019;116(27):13498-13507
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Lyme disease is a varied, multisystem disorder caused by the spiral-shaped bacteria Borrelia burgdorferi (Bb). Advanced stages of the disease can present with oligoarthritis, most commonly involving the knee joints. Peptidoglycan (PG) is a compound that makes up the cell envelope of Bb and other bacteria. It acts as a microbe-associated molecular pattern, which can trigger the immune system and induces pro-inflammatory responses. This article summarises a series of cell, human, and animal studies supporting the theory that PG is a contributor to persistent Lyme’s arthritis (LA) far beyond the eradication of the pathogen. Significantly elevated inflammatory markers as well as antibodies to PG and Bb itself have been found in patients with LA before and after antibiotic therapy. The inflammatory response to Bb PG seems to be particularly high when compared to other bacteria. In summary, the authors suggest that PG accumulation in the joints and subsequent persistent inflammation contribute to LA and that targeting the specific inflammatory pathways involved may yield potential therapeutic interventions. This article could be of interest to those looking to understand more about the mechanisms and specific inflammatory responses involved in LA.
Abstract
Lyme disease is a multisystem disorder caused by the spirochete Borrelia burgdorferi A common late-stage complication of this disease is oligoarticular arthritis, often involving the knee. In ∼10% of cases, arthritis persists after appropriate antibiotic treatment, leading to a proliferative synovitis typical of chronic inflammatory arthritides. Here, we provide evidence that peptidoglycan (PG), a major component of the B. burgdorferi cell envelope, may contribute to the development and persistence of Lyme arthritis (LA). We show that B. burgdorferi has a chemically atypical PG (PGBb) that is not recycled during cell-wall turnover. Instead, this pathogen sheds PGBb fragments into its environment during growth. Patients with LA mount a specific immunoglobulin G response against PGBb, which is significantly higher in the synovial fluid than in the serum of the same patient. We also detect PGBb in 94% of synovial fluid samples (32 of 34) from patients with LA, many of whom had undergone oral and intravenous antibiotic treatment. These same synovial fluid samples contain proinflammatory cytokines, similar to those produced by human peripheral blood mononuclear cells stimulated with PGBb In addition, systemic administration of PGBb in BALB/c mice elicits acute arthritis. Altogether, our study identifies PGBb as a likely contributor to inflammatory responses in LA. Persistence of this antigen in the joint may contribute to synovitis after antibiotics eradicate the pathogen. Furthermore, our finding that B. burgdorferi sheds immunogenic PGBb fragments during growth suggests a potential role for PGBb in the immunopathogenesis of other Lyme disease manifestations.
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Impact of Vitamin D Supplementation on Influenza Vaccine Response and Immune Functions in Deficient Elderly Persons: A Randomized Placebo-Controlled Trial.
Goncalves-Mendes, N, Talvas, J, Dualé, C, Guttmann, A, Corbin, V, Marceau, G, Sapin, V, Brachet, P, Evrard, B, Laurichesse, H, et al
Frontiers in immunology. 2019;10:65
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This randomized placebo-controlled double-blind trial investigated whether Vit-D supplementation in a sample of 38 deficient elderly persons, over 65-year olds, could improve influenza seroprotection and immune response. Vitamin D is known to both potentiate the innate immune response and inhibit the adaptive system, and so potentially modulate vaccination response. The participants were randomised into two arms: vitamin D supplementation group (D) and placebo group (P). The D group received 100,000 IU/15 days of cholecalciferol over a 3-month period after which both groups were given the influenza vaccine, and their blood was evaluated 28 days later. Several immune biomarkers were analysed including plasma cytokine profiles, phagocyte ROS production, and lymphocyte cells phenotyping to determine if Vitamin D enhanced immune response to the vaccination. No differences were found in serum ROS and antibody markers. However, Vitamin D supplementation did promote a higher TGFβ plasma level in response to influenza vaccination. Taken together, these results suggest that vitamin D supplementation is not an effective way to improve antibody response to influenza vaccine in deficient elderly people.
Abstract
Background: Immunosenescence contributes to reduced vaccine response in elderly persons, and is worsened by deficiencies in nutrients such as Vitamin (Vit-D). The immune system is a well-known target of Vit-D, which can both potentiate the innate immune response and inhibit the adaptive system, and so modulate vaccination response. Objective: This randomized placebo-controlled double-blind trial investigated whether Vit-D supplementation in deficient elderly persons could improve influenza seroprotection and immune response. Design: Deficient volunteers (Vit-D serum <30 ng/mL) were assigned (V1) to receive either 100,000 IU/15 days of cholecalciferol (D, n = 19), or a placebo (P, n = 19), over a 3 month period. Influenza vaccination was performed at the end of this period (V2), and the vaccine response was evaluated 28 days later (V3). At each visit, serum cathelicidin, immune response to vaccination, plasma cytokines, lymphocyte phenotyping, and phagocyte ROS production were assessed. Results: Levels of serum 25-(OH)D increased after supplementation (D group, V1 vs. V2: 20.7 ± 5.7 vs. 44.3 ± 8.6 ng/mL, p < 0.001). No difference was observed for serum cathelicidin levels, antibody titers, and ROS production in D vs. P groups at V3. Lower plasma levels of TNFα (p = 0.040) and IL-6 (p = 0.046), and higher ones for TFGβ (p = 0.0028) were observed at V3. The Th1/Th2 ratio was lower in the D group at V2 (D: 0.12 ± 0.05 vs. P: 0.18 ± 0.05, p = 0.039). Conclusions: Vit-D supplementation promotes a higher TGFβ plasma level in response to influenza vaccination without improving antibody production. This supplementation seems to direct the lymphocyte polarization toward a tolerogenic immune response. A deeper characterization of metabolic and molecular pathways of these observations will aid in the understanding of Vit-D's effects on cell-mediated immunity in aging. This clinical trial was registered at clinicaltrials.gov as NCT01893385.
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A pilot, open labelled, randomised controlled trial of hypertonic saline nasal irrigation and gargling for the common cold.
Ramalingam, S, Graham, C, Dove, J, Morrice, L, Sheikh, A
Scientific reports. 2019;9(1):1015
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The common cold is a viral upper respiratory tract infection which affects adults and children worldwide, often multiple times a year. A large number of viruses cause these infections, making targeted antiviral treatment impractical. This small, randomised, controlled pilot trial (not blinded) of 68 adults aimed to assess the impact of salt-water nasal washing and throat gargling as many times as required (on average 3 times a day for 5 days) within 48 hours of symptom on-set on study recruitment and retention, as well as acceptability, symptom duration and viral shedding. The researchers found that nasal irrigation and gargling with a saline solution was acceptable to study participants. Illness duration was shortened by 1.9 days in the intervention arm, with significant reductions in the duration of runny nose, blocked nose, sneezing, cough and hoarseness of voice. The average quality of life score was also higher in the intervention arm, although this failed to reach significance. Viral shedding was higher in the intervention arm, with over the counter medication use 36% lower. There was also a lower rate of infection spread within households for the intervention arm. The authors call for a larger, placebo controlled trial to confirm these findings. Nutrition Practitioners supporting immunity in relation to the common cold virus may want to discuss the use of saline nasal irrigation with their clients as a simple measure to reduce symptoms and spread.
Abstract
There are no antivirals to treat viral upper respiratory tract infection (URTI). Since numerous viruses cause URTI, antiviral therapy is impractical. As we have evidence of chloride-ion dependent innate antiviral response in epithelial cells, we conducted a pilot, non-blinded, randomised controlled trial of hypertonic saline nasal irrigation and gargling (HSNIG) vs standard care on healthy adults within 48 hours of URTI onset to assess recruitment (primary outcome). Acceptability, symptom duration and viral shedding were secondary outcomes. Participants maintained a symptom diary until well for two days or a maximum of 14 days and collected 5 sequential mid-turbinate swabs to measure viral shedding. The intervention arm prepared hypertonic saline and performed HSNIG. We recruited 68 participants (2.6 participants/week; November 2014-March 2015). A participant declined after randomisation. Another was on antibiotics and hence removed (Intervention:32, Control:34). Follow up data was available from 61 (Intervention:30, Control:31). 87% found HSNIG acceptable, 93% thought HSNIG made a difference to their symptoms. In the intervention arm, duration of illness was lower by 1.9 days (p = 0.01), over-the-counter medications (OTCM) use by 36% (p = 0.004), transmission within household contacts by 35% (p = 0.006) and viral shedding by ≥0.5 log10/day (p = 0.04). We hence need a larger trial to confirm our findings.
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Longitudinal Study of the Psoriasis-Associated Skin Microbiome during Therapy with Ustekinumab in a Randomized Phase 3b Clinical Trial.
Loesche, MA, Farahi, K, Capone, K, Fakharzadeh, S, Blauvelt, A, Duffin, KC, DePrimo, SE, Muñoz-Elías, EJ, Brodmerkel, C, Dasgupta, B, et al
The Journal of investigative dermatology. 2018;138(9):1973-1981
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Chronic plaque psoriasis is an immune-mediated disease of the skin and joints. A growing appreciation of the role of the innate immune system in psoriasis pathogenesis stems from the prominent role of inflammatory cytokines and cells associated with innate immunity in the disease and associations observed between psoriasis and genetic variations involved in innate immunity. The aim of this study was to assess changes of the skin microbiome in the setting of a longitudinal phase 3b study of patients receiving up to 2 years of ustekinumab therapy. Results show that prior to treatment, there were minor, body-site specific differences in microbial diversity and composition when comparing lesional with non-lesional skin. Microbial heterogeneity was greater in lesional skin than non-lesional skin. During ustekinumab treatment, the composition of microbiota diverged further between lesional and non-lesional skin across body sites. The divergence observed between lesional and non-lesional skin during ustekinumab treatment varied by body site. Authors conclude that their findings may help inform future study design and it may also have medically relevant implications for diagnostics and therapeutics involving the skin microbiome.
Abstract
Plaque psoriasis, a chronic inflammatory disease primarily affecting the skin, is thought to have a multifactorial etiology, including innate immune system dysregulation, environmental triggers, and genetic susceptibility. We sought to further understand the role of skin microbiota in psoriasis pathogenesis, as well as their response to therapy. We systematically analyzed dynamic microbiota colonizing psoriasis lesions and adjacent nonlesional skin in 114 patients prior to and during ustekinumab treatment in a phase 3b clinical trial. By sequencing the bacterial 16S ribosomal RNA gene from skin swab samples obtained at six anatomical sites, we identified minor, site-specific differences in microbial diversity and composition between pretreatment lesional and nonlesional skin. During therapy, microbial communities within lesional and nonlesional skin diverged, and body-site dispersion increased, reflecting microbial skin site-specificity. Microbiota demonstrated greater pretreatment heterogeneity in psoriatic lesions than in nonlesional skin, and variance increased as treatment progressed. Microbiota colonizing recurrent lesions did not overlap with pretreatment lesional microbiota, suggesting colonization patterns varied between initial and recurrent psoriatic lesions. While plaque psoriasis does not appear to be associated with specific microbes and/or microbial diversity, this large dataset provides insight into microbial variation associated with (i) disease in different body locations, (ii) initial versus recurrent lesions, and (iii) anti-IL12/23 therapy.
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Crying Time and RORγ/FOXP3 Expression in Lactobacillus reuteri DSM17938-Treated Infants with Colic: A Randomized Trial.
Savino, F, Garro, M, Montanari, P, Galliano, I, Bergallo, M
The Journal of pediatrics. 2018;192:171-177.e1
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The causes of infant colic are unknown, but growing evidence shows a possible link with the gut microbiome. Increased inflammation has also been found in infants with colic, and this could be linked to dysbiosis. This double-blind, placebo-controlled clinical trial investigated whether supplementation with the probiotic Lactobacillus reuteri (L reuteri) DSM 17938 could reduce the crying time and modify inflammation in a group of infants with colic. Infants enrolled in the trial were less than 12 weeks old, with a healthy birth weight and predominantly breastfed. Infants with colic were given either 5 million colony-forming units (CFU) of L reuteri DSM 17938 or a placebo daily for 1 month. Crying times were significantly shortened among infants with colic given the probiotic, whilst the concentration of transcription factors for cells that help to regulate the immune system increased significantly. Infants treated with the probiotic showed an increase in the percentage of Lactobacillus and a decrease in the inflammatory marker faecal calprotectin. The authors concluded that their findings support the hypothesis that dysbiosis and inflammation may contribute to the onset of infant colic.
Abstract
OBJECTIVES To evaluate crying time, retinoid-related orphan receptor-γ (RORγ) and forkhead box P3 (FOXP3) messenger RNA levels (transcription factors that can modulate T cell responses to gut microbes), and to investigate gut microbiota and fecal calprotectin in infants treated with Lactobacillus reuteri for infantile colic. STUDY DESIGN A double-blind, placebo-controlled randomized trial was conducted in primary care in Torino from August 1, 2015 to September 30, 2016. Patients suffering from infantile colic were randomly assigned to receive daily oral L reuteri (1 × 108 colony forming unit) or placebo for 1 month. Daily crying times were recorded in a structured diary. FOXP3 and RORγ messenger RNA in the peripheral blood was assessed with real-time TaqMan reverse transcription polymerase chain reaction. Gut microbiota and fecal calprotectin were evaluated. RESULTS After infants with colic were supplemented with L reuteri DSM 17938 for 30 days, crying times were significantly shorter among infants with colic in the probiotic group compared with infants in the placebo group (74.67 ± 25.04 [IQR = 79] minutes /day vs 147.85 [IQR = 135] minutes /day [P = .001]). The FOXP3 concentration increased significantly (P = .009), resulting in decreased RORγ/FOXP3 ratios: 0.61 (IQR = 0.60) at day 0 and 0.48 (IQR = 0.28) at day 30 (P = .028). Furthermore, the probiotic increased the percentage of Lactobacillus (P = .049) and decreased fecal calprotectin (P = .0001). CONCLUSIONS Infants with colic treated with L reuteri for 30 days had a significantly decreased crying time and an increased FOXP3 concentration, resulting in a decreased RORγ/FOXP3 ratio. The treatment reduced fecal calprotectin. TRIAL REGISTRATION ClinicalTrials.gov: NCT00893711.