Migraine without Aura and Subclinical Atherosclerosis in Young Females: Is Gut Microbiota to Blame?

To analyze the relationship between gut microbiota, metabolites and migraine: a two-sample Mendelian randomization study

Background

It has been suggested in several observational studies that migraines are associated with the gut microbiota. It remains unclear, however, how the gut microbiota and migraines are causally related.

Methods

We performed a bidirectional two-sample mendelian randomization study. Genome-wide association study (GWAS) summary statistics for the gut microbiota were obtained from the MiBioGen consortium (n = 18,340) and the Dutch Microbiota Project (n = 7,738). Pooled GWAS data for plasma metabolites were obtained from four different human metabolomics studies. GWAS summary data for migraine (cases = 48,975; controls = 450,381) were sourced from the International Headache Genetics Consortium. We used inverse-variance weighting as the primary analysis. Multiple sensitivity analyses were performed to ensure the robustness of the estimated results. We also conducted reverse mendelian randomization when a causal relationship between exposure and migraine was found.

Results

LachnospiraceaeUCG001 (OR = 1.12, 95% CI: 1.05-1.20) was a risk factor for migraine. Blautia (OR = 0.93, 95% CI: 0.88-0.99), Eubacterium (nodatum group; OR = 0.94, 95% CI: 0.90-0.98), and Bacteroides fragilis (OR = 0.97, 95% CI: 0.94-1.00) may have a suggestive association with a lower migraine risk. Functional pathways of methionine synthesis (OR = 0.89, 95% CI: 0.83-0.95) associated with microbiota abundance and plasma hydrocinnamate (OR = 0.85, 95% CI: 0.73-1.00), which are downstream metabolites of Blautia and Bacteroides fragilis, respectively, may also be associated with lower migraine risk. No causal association between migraine and the gut microbiota or metabolites was found in reverse mendelian randomization analysis. Both significant horizontal pleiotropy and significant heterogeneity were not clearly identified.

Conclusion

This Mendelian randomization analysis showed that LachnospiraceaeUCG001 was associated with an increased risk of migraine, while some bacteria in the gut microbiota may reduce migraine risk. These findings provide a reference for a deeper comprehension of the role of the gut-brain axis in migraine as well as possible targets for treatment interventions.

Migraine and the microbiota. Can probiotics be beneficial in its prevention? - a narrative review

Migraine is a recurrent disease of the central nervous system that affects an increasing number of people worldwide causing a continuous increase in the costs of treatment. The mechanisms underlying migraine are still unclear but recent reports show that people with migraine may have an altered composition of the intestinal microbiota. It is well established that the gut-brain axis is involved in many neurological diseases, and probiotic supplementation may be an interesting treatment option for these conditions. This review collects data on the gastrointestinal and oral microbiota in people suffering from migraine and the use of probiotics as a novel therapeutic approach in its treatment.

NASH/NAFLD-Related Hepatocellular Carcinoma: An Added Burden

Hepatocellular carcinoma (HCC) is the most frequently found primary malignancy of the liver, showing an accelerated upward trend over the past few years and exhibiting an increasing relationship with metabolic syndrome, obesity, dyslipidemia and type 2 diabetes mellitus. The connection between these risk factors and the occurrence of HCC is represented by the occurrence of non-alcoholic fatty liver disease (NAFLD) which later, based on genetic predisposition and various triggers (including the presence of chronic inflammation and changes in the intestinal microbiome), may evolve into HCC. HCC in many cases is diagnosed at an advanced stage and can be an incidental finding. We present such a scenario in the case of a 41-year-old male patient who had mild obesity and mixed dyslipidemia, no family or personal records of digestive pathologies and who recently developed a history of progressive fatigue, dyspepsia and mild upper abdominal discomfort initially thought to be linked to post-COVID syndrome, as the patient had COVID-19 pneumonia a month prior. The abdominal ultrasound revealed a mild hepatomegaly with bright liver aspect of the right lobe (diffuse steatosis), a large zone of focal steatosis (segments IV, III and II) and a left lobe tumoral mass, highly suggestive of malignancy. Point shear wave elastography at the right lobe ruled out an end-stage chronic liver disease. Additional laboratory investigations, imaging studies (magnetic resonance imaging) and histopathological examination of liver fragments confirmed a highly aggressive HCC, with poorly differentiation-G3, (T4, N 1M 0) and stage IVA, associated with nonalcoholic steatohepatitis (NASH). A sorafenib course of treatment was attempted, but the patient discontinued it due to severe side effects. The subsequent evolution was extremely unfavorable, with rapid degradation, a few episodes of upper digestive bleeding, hepatic insufficiency and mortality in a couple of months. Conclusions: Diagnosis of NASH-related HCC is either an accidental finding or is diagnosed at an advanced stage. In order to earn time for a proper treatment, it becomes important to diagnose it at an early stage, for which regular check-ups should be performed in groups having the risk factors related to it. Patients suffering from obesity and mixed dyslipidemia should undergo periodic abdominal ultrasound examinations. This should be emphasized even more in the cases showing NASH. Complaints of any kind post-COVID-19 should be dealt with keenly as little is yet known about its virulence and its long-term side effects.

A causal effects of gut microbiota in the development of migraine

BACKGROUND

The causal association between the gut microbiome and the development of migraine and its subtypes remains unclear.

METHODS

The single nucleotide polymorphisms concerning gut microbiome were retrieved from the gene-wide association study (GWAS) of the MiBioGen consortium. The summary statistics datasets of migraine, migraine with aura (MA), and migraine without aura (MO) were obtained from the GWAS meta-analysis of the International Headache Genetics Consortium (IHGC) and FinnGen consortium. Inverse variance weighting (IVW) was used as the primary method, complemented by sensitivity analyses for pleiotropy and increasing robustness.

RESULTS

In IHGC datasets, ten, five, and nine bacterial taxa were found to have a causal association with migraine, MA, and MO, respectively, (IVW, all P < 0.05). Genus.Coprococcus3 and genus.Anaerotruncus were validated in FinnGen datasets. Nine, twelve, and seven bacterial entities were identified for migraine, MA, and MO, respectively. The causal association still exists in family.Bifidobacteriaceae and order.Bifidobacteriales for migraine and MO after FDR correction. The heterogeneity and pleiotropy analyses confirmed the robustness of IVW results.

CONCLUSION

Our study demonstrates that gut microbiomes may exert causal effects on migraine, MA, and MO. We provide novel evidence for the dysfunction of the gut-brain axis on migraine. Future study is required to verify the relationship between gut microbiome and the risk of migraine and its subtypes and illustrate the underlying mechanism between them.

Gallstone Disease and Bacterial Metabolic Performance of Gut Microbiota in Middle-Aged and Older Patients

Background

Gallstone disease (GSD) is more commonly presented in aged people.

Purpose

The purpose of the study was to explore the insights of metabolic performance of bacterial species from gut microbiota as well as the clinical background in middle-aged and elderly patients with GSD.

Patients and Methods

This is an observational study concerning 120 research participants. Of those, 90 patients with symptomatic GSD addressed for cholecystectomy, average age 59.83 ± 15.32 years: 45 with cholesterol rich gallstones (CGSs), 45 with pigment gallstones (PGSs) and 30 healthy controls joined this observational study. Clinical examination, lab work-ups, upper and lower digestive video-endoscopies, abdominal ultrasound/CT and gallbladder motility assessment by Dodd’s method were performed. Overall stool dysbiosis (DB) was assessed as 1 = minor, 2 = mild, 3 = severe, species being identified by matrix-assisted laser desorption ionization method. Stool samples from dysbiotic patients were analyzed by a next generation sequencing method with operational taxonomic unit identification.

Results

Patients with GSD presented with a significant high range of overall gut DB (p < 0.0001) when compared with controls. Those with CGSs compared with those having PGSs displayed significant clinical differences related to elderly age, lifestyle and diet particularities, obesity, dyslipidemia, nonalcoholic fatty liver disease, hypertension, type 2 diabetes mellitus or impaired glucose tolerance, as well as motility disturbances of gallbladder with a decrease of the ejection fraction. Significant increase of overall DB range and alterations of several functional bacterial species with a decrease of butyrate, lactate, acetate/propionate and methane producers, mucin degrading bacteria, biodiversity index of microbiota, as well as an increase of lipopolysaccharide positive bacteria were significantly present in patients with CGSs.

Conclusion

Middle-aged and elderly patients with GSD and a clinical background characterized by particular lifestyle, metabolic and gallbladder motility issues displayed significant modifications of biodiversity, overall gut DB and alterations of several functional bacterial species, with a decrease of their metabolic performance.

Dyspepsia and Gut Microbiota in Female Patients with Postcholecystectomy Syndrome

BACKGROUND

Gallstone disease (GSD) represents one of the most frequent digestive disorders, highly reported in female gender. The purpose of the study was to explore the clinical and gut microbiota particularities of female patients with postcholecystectomy syndrome (PCS) and the possible relationship between gut dysbiosis (DB) and abdominal complaints.

PATIENTS AND METHODS

In total, 129 female participants: 104 outpatients divided into two equal groups, 52 PCS (+), 52 PCS (-) and 25 healthy controls were consecutively enrolled in this observational study. Patients underwent clinical examination with assessment of pain, bloating, transit disturbances, abdominal ultrasound/computer tomography/magnetic resonance imaging/endoscopic retrograde cholangiopancreatography, upper and lower digestive endoscopies. Laboratory work-ups and stool microbiology assessments were performed for all study participants (patients and controls). Stool microorganisms were identified by matrix-assisted laser desorption ionization - time-of-flight- mass spectrometry and in patients with DB also by next-generation sequencing.

RESULTS

Older age, complicated gallstones disease, associated conditions like diabetes mellitus/impaired glucose tolerance and irritable bowel syndrome were significantly present in PCS (+) group, as well as sedentary lifestyle and diets characterized by a low fiber intake (p<0.0001). PCS (+) patients displayed significant differences related to the incidence and severity of overall gut microbiota DB, decreased H index of biodiversity and the unbalanced Firmicutes/Bacteroidetes (F/B) ratios by comparison to the PCS (-) group (p<0.0001). Strong positive correlations of the severity of overall DB with bloating and the intestinal habit disorders, as well as of F/B ratios to all abdominal symptoms were noted.

CONCLUSION

PCS in female patients was associated with older age, sedentary lifestyle, specific dietary habits, history of complicated gallstone disease, diabetes mellitus/impaired glucose tolerance and irritable bowel syndrome, as well as gut microbiota particularities. Overall DB and unbalanced F/B ratios were strongly correlated to abdominal complaints.

Role of herbal medicine for prevention and treatment of migraine

Migraine is a disabling neurovascular disease with unilateral or bilateral pulsatile headache, which intensively affects human health and quality of life due to high morbidity worldwide. Migraine is commonly accompanied by abnormal pain sensitization, neuroinflammatory response, and vasomotor dysfunction. Owing to the management dilemmas of migraine, there is an urgent need to develop effective and low-cost therapies. In recent years, herbal medicines as a promising strategy with analgesic activity and minor side effect, have been proposed for the prevention and treatment of migraine. Considering the lack of a review integrating experimental studies regarding the herbal treatment of migraine, this review systematically summarizes the important potential applications of herbal medicines in ameliorating migraine via multiple therapeutic targets and pathways, as well as provides a reference for further development of novel antimigraine drugs.

Kynurenine Pathway of Tryptophan Metabolism in Migraine and Functional Gastrointestinal Disorders

Migraine, the leading cause of disability in the population aged below 50, is associated with functional gastrointestinal (GI) disorders (FGIDs) such as functional nausea, cyclic vomiting syndrome, and irritable bowel syndrome (IBS). Conversely, changes in intestinal GI transit may cause diarrhea or constipation and are a component of the autonomic symptoms associated with pre- and post-dorsal phases of migraine attack. These mutual relationships provoke a question on a common trigger in migraine and FGIDs. The kynurenine (l-kyn) pathway (KP) is the major route for l-tryptophan (l-Trp) metabolism and transforms l-Trp into several neuroactive compounds. Changes in KP were reported in both migraine and FGIDs. Migraine was largely untreatable, but several drugs approved lately by the FDA, including monoclonal antibodies for calcitonin gene-related peptide (CGRP) and its receptor, create a hope for a breakthrough in migraine treatment. Derivatives of l-kyn were efficient in pain relief with a mechanism including CGRP inhibition. KP products are important ligands to the aryl hydrocarbon receptor (AhR), whose activation is implicated in the pathogenesis of GI and migraine. Toll-like receptors (TLRs) may play a role in migraine and IBS pathogeneses, and KP metabolites detected downstream of TLR activation may be an IBS marker. The TLR4 signaling was observed in initiating and maintaining migraine-like behavior through myeloid differentiation primary response gene 88 (MyD88) in the mouse. The aim of this review is to justify the view that KP modulation may provide common triggers for migraine and FGIDs with the involvement of TLR, AhR, and MyD88 activation.

The role of microbiota-gut-brain axis in neuropsychiatric and neurological disorders

Emerging evidence indicates that the gut microbiota play a crucial role in the bidirectional communication between the gut and the brain suggesting that the gut microbes may shape neural development, modulate neurotransmission and affect behavior, and thereby contribute to the pathogenesis and/or progression of many neurodevelopmental, neuropsychiatric, and neurological conditions. This review summarizes recent data on the role of microbiota-gut-brain axis in the pathophysiology of neuropsychiatric and neurological disorders including depression, anxiety, schizophrenia, autism spectrum disorders, Parkinson's disease, migraine, and epilepsy. Also, the involvement of microbiota in gut disorders co-existing with neuropsychiatric conditions is highlighted. We discuss data from both in vivo preclinical experiments and clinical reports including: (1) studies in germ-free animals, (2) studies exploring the gut microbiota composition in animal models of diseases or in humans, (3) studies evaluating the effects of probiotic, prebiotic or antibiotic treatment as well as (4) the effects of fecal microbiota transplantation.