ObjectiveTo investigate host and gut-microbiota related Tryptophan metabolism in hand osteoarthritis (HOA).MethodsThe baseline serum concentration of 20 Tryptophan metabolites was measured in 416... Show moreObjectiveTo investigate host and gut-microbiota related Tryptophan metabolism in hand osteoarthritis (HOA).MethodsThe baseline serum concentration of 20 Tryptophan metabolites was measured in 416 HOA patients in a cross-sectional analysis of the DIGICOD cohort. Tryptophan metabolites levels, metabolite-ratios and metabolism pathway activation were compared between erosive (N = 141) and non-erosive HOA (N = 275) by multiple logistic regressions adjusted on age, BMI and sex. The association between Tryptophan metabolite levels and HOA symptoms was investigated by a Spearman's rank correlation analysis.ResultsFour serum Tryptophan metabolites, eight metabolite ratios and one metabolism pathway were associated with erosive HOA. Erosive HOA was negatively associated with Tryptophan (odds ratio (OR) = 0.41, 95% confidence interval [0.24–0.70]), indole-3-aldehyde (OR = 0.67 [0.51–0.90]) and 3-OH-anthranilic acid (OR = 1.32 [1.13–1.54]) and positively with 5-OH-Tryptophan levels (OR = 1.41 [1.13–1.77]). The pro-inflammatory kynurenine–indoleamine 2,3-dioxygenase pathway was upregulated in erosive HOA (OR = 1.60 [1.11–2.29]). Eleven metabolites were correlated with HOA symptoms and were mostly pain-related. Serotonin and N-acetyl serotonin levels were negatively correlated with number of tender joints. Indole-3-aldehyde level was negatively correlated and 3-OH-anthranilic acid, 3-OH-kynurenine and 5-OH-Tryptophan levels were positively correlated with number of patients-reported painful joints. Quinolinic acid and 3-OH-kynurenine levels correlated positively with AUSCAN pain.ConclusionsTryptophan metabolites disturbance is associated with erosive HOA and pain and emphasize the role of low-grade inflammation and gut dysbiosis in HOA. Show less
BackgroundThe causal association between the gut microbiome and the development of migraine and its subtypes remains unclear.MethodsThe single nucleotide polymorphisms concerning gut microbiome... Show moreBackgroundThe causal association between the gut microbiome and the development of migraine and its subtypes remains unclear.MethodsThe 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.ResultsIn 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.ConclusionOur 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. Show less
Background: The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune... Show moreBackground: The gut microbiome plays an important role in immune modulation. Specifically, presence or absence of certain gut bacterial taxa has been associated with better antitumor immune responses. Furthermore, in trials using fecal microbiota transplantation (FMT) to treat melanoma patients unresponsive to immune checkpoint inhibitors (ICI), complete responses (CR), partial responses (PR), and durable stable disease (SD) have been observed. However, the underlying mechanism determining which patients will or will not respond and what the optimal FMT composition is, has not been fully elucidated, and a discrepancy in microbial taxa associated with clinical response has been observed between studies. Furthermore, it is unknown whether a change in the microbiome itself, irrespective of its origin, or FMT from ICI responding donors, is required for reversion of ICI-unresponsiveness. To address this, we will transfer microbiota of either ICI responder or nonresponder metastatic melanoma patients via FMT. Methods: In this randomized, double-blinded phase Ib/IIa trial, 24 anti-PD1-refractory patients with advanced stage cutaneous melanoma will receive an FMT from either an ICI responding or nonresponding donor, while continuing anti-PD-1 treatment. Donors will be selected from patients with metastatic melanoma treated with anti-PD-1 therapy. Two patients with a good response (& GE; 30% decrease according to RECIST 1.1 within the past 24 months) and two patients with progression (& GE; 20% increase according to RECIST 1.1 within the past 3 months) will be selected as ICI responding or nonresponding donors, respectively. The primary endpoint is clinical benefit (SD, PR or CR) at 12 weeks, confirmed on a CT scan at 16 weeks. The secondary endpoint is safety, defined as the occurrence of grade & GE; 3 toxicity. Exploratory endpoints are progression-free survival and changes in the gut microbiome, metabolome, and immune cells. Discussion: Transplanting fecal microbiota to restore the patients' perturbed microbiome has proven successful in several indications. However, less is known about the potential role of FMT to improve antitumor immune response. In this trial, we aim to investigate whether administration of FMT can reverse resistance to anti-PD-1 treatment in patients with advanced stage melanoma, and whether the ICI-responsiveness of the feces donor is associated with its effectiveness. Show less
Background and aims: Choline has been shown to exert atherogenic effects in Apoe- /- and Ldlr- /-mice, related to its conversion by gut bacteria into trimethylamine (TMA) that is converted by the... Show moreBackground and aims: Choline has been shown to exert atherogenic effects in Apoe- /- and Ldlr- /-mice, related to its conversion by gut bacteria into trimethylamine (TMA) that is converted by the liver into the proinflammatory metabolite trimethylamine-N-oxide (TMAO). Since butyrate beneficially modulates the gut microbiota and has anti-inflammatory and antiatherogenic properties, the aim of the present study was to investigate whether butyrate can alleviate choline-induced atherosclerosis. To this end, we used APOE*3-Leiden.CETP mice, a well-established atherosclerosis-prone model with human-like lipoprotein metabolism. Methods: Female APOE*3-Leiden.CETP mice were fed an atherogenic diet alone or supplemented with choline, butyrate or their combination for 16 weeks. Results: Interestingly, choline protected against fat mass gain, increased the abundance of anti-inflammatory gut microbes, and increased the expression of gut microbial genes involved in TMA and TMAO degradation. Butyrate similarly attenuated fat mass gain and beneficially modulated the gut microbiome, as shown by increased abundance of anti-inflammatory and short chain fatty acid-producing microbes, and inhibited expression of gut microbial genes involved in lipopolysaccharide synthesis. Both choline and butyrate upregulated hepatic expression of flavin-containing monooxygenases, and their combination resulted in highest circulating TMAO levels. Nonetheless, choline, butyrate and their combination did not influence atherosclerosis development, and TMAO levels were not associated with atherosclerotic lesion size. Conclusions: While choline and butyrate have been reported to oppositely modulate atherosclerosis development in Apoe-/-and Ldlr-/-mice as related to changes in the gut microbiota, both dietary constituents did not affect atherosclerosis development while beneficially modulating the gut microbiome in APOE*3-Leiden.CETP mice. Show less
Background and aimsCholine has been shown to exert atherogenic effects in Apoe−/− and Ldlr−/− mice, related to its conversion by gut bacteria into trimethylamine (TMA) that is converted by the... Show moreBackground and aimsCholine has been shown to exert atherogenic effects in Apoe−/− and Ldlr−/− mice, related to its conversion by gut bacteria into trimethylamine (TMA) that is converted by the liver into the proinflammatory metabolite trimethylamine-N-oxide (TMAO). Since butyrate beneficially modulates the gut microbiota and has anti-inflammatory and antiatherogenic properties, the aim of the present study was to investigate whether butyrate can alleviate choline-induced atherosclerosis. To this end, we used APOE*3-Leiden.CETP mice, a well-established atherosclerosis-prone model with human-like lipoprotein metabolism.MethodsFemale APOE*3-Leiden.CETP mice were fed an atherogenic diet alone or supplemented with choline, butyrate or their combination for 16 weeks.ResultsInterestingly, choline protected against fat mass gain, increased the abundance of anti-inflammatory gut microbes, and increased the expression of gut microbial genes involved in TMA and TMAO degradation. Butyrate similarly attenuated fat mass gain and beneficially modulated the gut microbiome, as shown by increased abundance of anti-inflammatory and short chain fatty acid-producing microbes, and inhibited expression of gut microbial genes involved in lipopolysaccharide synthesis. Both choline and butyrate upregulated hepatic expression of flavin-containing monooxygenases, and their combination resulted in highest circulating TMAO levels. Nonetheless, choline, butyrate and their combination did not influence atherosclerosis development, and TMAO levels were not associated with atherosclerotic lesion size.ConclusionsWhile choline and butyrate have been reported to oppositely modulate atherosclerosis development in Apoe−/− and Ldlr−/− mice as related to changes in the gut microbiota, both dietary constituents did not affect atherosclerosis development while beneficially modulating the gut microbiome in APOE*3-Leiden.CETP mice. Show less
Li, R.; Boer, C.G.; Oei, L.; Medina-Gomez, C. 2021
Purpose of the review The human gut harbors a complex community of microbes that influence many processes regulating musculoskeletal development and homeostasis. This review gives an update on the... Show morePurpose of the review The human gut harbors a complex community of microbes that influence many processes regulating musculoskeletal development and homeostasis. This review gives an update on the current knowledge surrounding the impact of the gut microbiota on musculoskeletal health, with an emphasis on research conducted over the last three years. Recent findings The gut microbiota and their metabolites are associated with sarcopenia, osteoporosis, osteoarthritis, and rheumatoid arthritis. The field is moving fast from describing simple correlations to pursue establishing causation through clinical trials. The gut microbiota and their microbial-synthesized metabolites hold promise for offering new potential alternatives for the prevention and treatment of musculoskeletal diseases given its malleability and response to environmental stimuli. Show less
