Change in gut microbiota for eczema: Implications for novel therapeutic strategies

Multikingdom and functional gut microbiota markers for autism spectrum disorder

Associations between the gut microbiome and autism spectrum disorder (ASD) have been investigated although most studies have focused on the bacterial component of the microbiome. Whether gut archaea, fungi and viruses, or function of the gut microbiome, is altered in ASD is unclear. Here we performed metagenomic sequencing on faecal samples from 1,627 children (aged 1-13 years, 24.4% female) with or without ASD, with extensive phenotype data. Integrated analyses revealed that 14 archaea, 51 bacteria, 7 fungi, 18 viruses, 27 microbial genes and 12 metabolic pathways were altered in children with ASD. Machine learning using single-kingdom panels showed area under the curve (AUC) of 0.68 to 0.87 in differentiating children with ASD from those that are neurotypical. A panel of 31 multikingdom and functional markers showed a superior diagnostic accuracy with an AUC of 0.91, with comparable performance for males and females. Accuracy of the model was predominantly driven by the biosynthesis pathways of ubiquinol-7 or thiamine diphosphate, which were less abundant in children with ASD. Collectively, our findings highlight the potential application of multikingdom and functional gut microbiota markers as non-invasive diagnostic tools in ASD.

Efficacy and safety of purslane (Portulaca oleracea) for mild to moderate chronic hand eczema; A randomized, double-blind, placebo-controlled clinical trial

INTRODUCTION

Chronic hand eczema (CHE) is a common skin inflammation with a complex pathophysiology. Due to its anti-inflammatory properties, Portulaca oleracea L. (purslane) is traditionally used in Persian medicine for skin ailments. This study aimed to evaluate the safety and efficacy of a standardized purslane extract (based on traditional Persian medicine) for adults with mild or moderately severe CHE.

METHODS

A randomized, double-blind, placebo-controlled clinical trial was conducted at Razi Hospital in Iran from January to June 2022. Participants were randomly allocated to receive an oral purslane or placebo syrup plus topical Vaseline for four weeks. Seventy participants were randomly allocated into the intervention (n = 35) and placebo (n = 35) groups. The primary outcomes were the extent and severity of CHE symptoms over the four weeks after adjusting for age, gender and baseline score. Secondary outcomes were quality of life, symptom recurrence, treatment satisfaction, and adverse events.

RESULTS

After 4 weeks of treatment, compared to the placebo group (n = 31), the purslane group (n = 31) had significantly lower physician-reported fissure scores (adjusted mean difference (adjMD): -0.50, 95 %CI -3.93 to -0.34, p = 0.043), participant-reported itching (adjMD -0.51, 95 %CI -2.32 to -0.31, p = 0.041), dryness (adjMD -1.46, 95 %CI -2.89 to -0.03, p = 0.045), and total itching, dryness and thickness (adjMD -2.36, 95 %CI -6.23 to -1.51, p = 0.023) scores. Fourteen participants (purslane n = 10; placebo n = 4, p = 0.068) experienced adverse events of mild to moderate severity.

CONCLUSION

Purslane has some promising effects for reducing the extent and severity of CHE symptoms, and no direct comparisons have been made with commonly used treatments. Future multicenter trials and mechanistic studies are warranted to establish the safety and effectiveness of purslane as a potential therapeutic agent for CHE.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (IRCT20200707048040N1).

The Gut Microbiome and Acute Leukemia: Implications for Early Diagnostic and New Therapies

Acute leukemia (AL), one of the hematological malignancies, shows high heterogeneity. Tremendous progresses are achieved in treating AL with novel targeted drugs and allogeneic hematopoietic stem cell transplantation, there are numerous issues including pathogenesis, early diagnosis, and therapeutic efficacy of AL to be solved. In recent years, an increasing number of studies regarding microbiome have shed more lights on the role of gut microbiota in promoting AL progression. Mechanisms related to the role of gut microbiota in enhancing AL genesis are summarized in the present work, especially on critical pathways like leaky gut, bacterial dysbiosis, microorganism-related molecular patterns, and bacterial metabolites, resulting in AL development. Additionally, the potential of gut microbiota as the biomarker for early AL diagnosis is discussed. It also outlooks therapies targeting gut microbiota for preventing AL development.

A Placebo-controlled double-blinded test of the biodiversity hypothesis of immune-mediated diseases: Environmental microbial diversity elicits changes in cytokines and increase in T regulatory cells in young children

BACKGROUND

According to the biodiversity hypothesis of immune-mediated diseases, lack of microbiological diversity in the everyday living environment is a core reason for dysregulation of immune tolerance and - eventually - the epidemic of immune-mediated diseases in western urban populations. Despite years of intense research, the hypothesis was never tested in a double-blinded and placebo-controlled intervention trial.

OBJECTIVE

We aimed to perform the first placebo-controlled double-blinded test that investigates the effect of biodiversity on immune tolerance.

METHODS

In the intervention group, children aged 3-5 years were exposed to playground sand enriched with microbially diverse soil, or in the placebo group, visually similar, but microbially poor sand colored with peat (13 participants per treatment group). Children played twice a day for 20 min in the sandbox for 14 days. Sand, skin and gut bacterial, and blood samples were taken at baseline and after 14 days. Bacterial changes were followed for 28 days. Sand, skin and gut metagenome was determined by high throughput sequencing of bacterial 16 S rRNA gene. Cytokines were measured from plasma and the frequency of blood regulatory T cells was defined as a percentage of total CD3 +CD4 + T cells.

RESULTS

Bacterial richness (P < 0.001) and diversity (P < 0.05) were higher in the intervention than placebo sand. Skin bacterial community, including Gammaproteobacteria, shifted only in the intervention treatment to resemble the bacterial community in the enriched sand (P < 0.01). Mean change in plasma interleukin-10 (IL-10) concentration and IL-10 to IL-17A ratio supported immunoregulation in the intervention treatment compared to the placebo treatment (P = 0.02). IL-10 levels (P = 0.001) and IL-10 to IL-17A ratio (P = 0.02) were associated with Gammaproteobacterial community on the skin. The change in T_reg frequencies was associated with the relative abundance of skin Thermoactinomycetaceae 1 (P = 0.002) and unclassified Alphaproteobacteria (P < 0.001). After 28 days, skin bacterial community still differed in the intervention treatment compared to baseline (P < 0.02).

CONCLUSIONS

This is the first double-blinded placebo-controlled study to show that daily exposure to microbial biodiversity is associated with immune modulation in humans. The findings support the biodiversity hypothesis of immune-mediated diseases. We conclude that environmental microbiota may contribute to child health, and that adding microbiological diversity to everyday living environment may support immunoregulation.

The Gut Microbiome and Hepatocellular Carcinoma: Implications for Early Diagnostic Biomarkers and Novel Therapies

Hepatocellular carcinoma (HCC) ranks the third place among all causes inducing cancer-associated mortality, worldwide. HCC nearly exclusively occurs in cases suffering from chronic liver disease (CLD), which results from the vicious cycle of liver damage, inflammation, and regeneration possibly lasting for dozens of years. Recently, more and more investigation on microbiome-gut-liver axis enhances our understanding toward how gut microbiota promotes liver disease and even HCC development. In this review, we summarize the mechanisms underlying the effect of gut microbiota on promoting HCC occurrence, with the focus on key pathways such as bacterial dysbiosis, leaky gut, bacterial metabolites, and microorganism-related molecular patterns, which promote liver inflammation, genotoxicity, and fibrosis that finally lead to cancer occurrence. Furthermore, we discuss gut microbiota's important potential to be the early diagnostic biomarker for HCC. Gut microbiota may be the candidate targets to simultaneously prevent CLD and HCC occurrence among advanced liver disease cases. We outlook the gut microbiota-targeting treatments in detail to prevent CLD and HCC progression.

Probiotics in the Management of Atopic Dermatitis for Children: A Case-Based Review

Background

Atopic dermatitis or eczema is one of the most common dermatologic problems, especially in children. Several studies have hypothesized that alteration of gut-colonizing microbes might have induced and conditioned the development of the disease. Thus, modulation of microbial diversity and abundance might help alleviate symptoms and conditions for patients. Given the ability of commensal and symbiotic microorganisms in modulating the immune system, probiotics administration has been studied in previous research in the management of eczema. However, until today, there are conflicting results between studies making inconclusive recommendations towards probiotics supplementation in the management of atopic dermatitis. This case-based review was done to assess and evaluate the therapeutic efficacy of probiotics supplementation in the management of eczema in children.

Method

An electronic database search was conducted in PubMed-NCBI, Cochrane, EBSCO, ProQuest, and SCOPUS in March 2020. Individual studies and reviews were then gathered for screening using predetermined inclusion and exclusion criteria. The included studies were then critically appraised for their validity and importance.

Result

A total of 5 studies, all of which were RCTs, were included in this review. Out of all the studies included, 4 showed no clinically significant improvements in using probiotics in the management of eczema in children as they did not pass the minimal clinically important difference (MCID) of eczema severity as determined by SCORAD (SCORing Atopic Dermatitis).

Conclusion

Supplementation of probiotics in the management of eczema in children does not show a clinically relevant difference vs. standard treatment in reducing eczema severity.

Whole exome sequencing detects novel variants in Saudi children diagnosed with eczema

BACKGROUND

Eczema is also known as atopic dermatitis is well-known for the skin disease globally. In Saudi Arabia, exome sequencing studies have not been documented. The purpose of this study was to scrutinize the disease causing mutations in children affected with eczema with exome sequencing in the Saudi population.

METHODS

We recruited randomly three sporadic cases of children diagnosed with eczema and simultaneously, three more cases were adopted for control samples. Exome sequencing was carried out by applying a pipeline that captures all the variants of concern related to the samples by using the Ion torrent.

RESULTS

In this study, we have documented 49 variants, among which 37 variants were confirmed through eczema children and remaining 30 variants through control children. However, from the analysis of the 6 samples, we have identified rs10192157 (1646C>T; Thr549Ile), rs2899642 (27C>G; Asn9Lys), chr1:152127950 (1625G>A; Gly542Asp) and chr1:152128041 (1534C>G; Gly512Arg) variants which are rarely linked to the disease eczema. In the rs10192157, we have documented these mutations in all three eczema children and one in the control; the rs2899642 mutation appeared in only a couple of eczema children, whereas the mutation in the chr1:152127950 regions appeared in only one eczema patient. However, the chr1:152128041 mutations appeared in only one case of eczema and also in two control children.

CONCLUSION

Our study revealed four mutations which had not previously been connected with eczema within the database. However, the rs10192157 and rs2899642 mutations were documented with asthma disease. The remaining mutations such as chr1:152127950 and chr1:152128041 have not been reported anywhere else. This study recommends screening these 4 mutations in eczema cases and their relevant controls to confirm the prevalence in the Saudi population. It is recommended that future studies examine the 4 mutations in detail.