Gut Microbiota Signatures in Graves’ Disease: Key Associations and Biomarker Potential Original paper
Researched by:
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Giorgos Aristotelous
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Giorgos Aristotelous
Read MoreGiorgos — BSc, MSc. Giorgos is an exercise scientist whose training and professional practice sit at the intersection of human performance, clinical health, and emerging microbiome science. He holds a BSc in Sports Science & Physical Education from Aristotle University (2012) and an MSc in Exercise & Health from Democritus University (2016), where his graduate work explored physiological adaptations to training across the lifespan. Now in his 15th year of practice, Giorgos pairs evidence-based coaching (ACSM-CPT, NSCA, USA Weightlifting) with a research-driven interest in how physical activity, body composition, and musculoskeletal integrity shape—and are shaped by—host–microbiome dynamics.
Fact-checked by:
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Karen Pendergrass
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Karen Pendergrass
Read MoreKaren Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease—four years before the first published case study.
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Autoimmune Diseases
Autoimmune Diseases
Autoimmune disease is when the immune system mistakenly attacks the body's tissues, often linked to imbalances in the microbiome, which can disrupt immune regulation and contribute to disease development.
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Graves Disease
Graves Disease
OverviewGraves’ Disease (GD) affects approximately 0.5% of the population, predominantly women. First-line treatment options—antithyroid medications, radioactive iodine, and surgery— often result in significant side effects, incomplete remissions, and frequent relapses. Further, current first-line treatment options focus on symptoms management, and reflect an inadequate understanding of the etiology of the condition. However, recent research reveals a […]
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Giorgos Aristotelous
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Researched by:
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Giorgos Aristotelous
ID
Giorgos Aristotelous
Read More
Fact-checked by:
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Karen Pendergrass
ID
Karen Pendergrass
Read More
Microbiome Signatures identifies and validates condition-specific microbiome shifts and interventions to accelerate clinical translation. Our multidisciplinary team supports clinicians, researchers, and innovators in turning microbiome science into actionable medicine.
Giorgos Aristotelous
Location
China
Sample Site
Feces
Species
Homo sapiens
What was studied?
The study investigated the associations between gut microbiota composition and thyroidal function status in Chinese patients with Graves’ disease (GD), focusing on how gut microbial profiles relate to clinical characteristics and thyroid autoantibody levels, particularly thyrotropin receptor antibody (TRAb). Using 16S rDNA high-throughput sequencing, the researchers compared the gut microbiota of untreated primary GD patients with healthy controls and further analyzed changes in microbiota after anti-thyroid drug therapy (Methimazole). The study aimed to identify specific microbial signatures linked to GD and the restoration of thyroid function following treatment, and to explore correlations between gut microbial taxa and thyroid autoimmunity markers.
Who was studied?
The study enrolled 15 adult patients (7 males, 8 females) with newly diagnosed, untreated primary GD from Jinling Hospital, Southeast University, Nanjing, China. Fourteen healthy adult volunteers (6 males, 8 females) served as controls. All participants were between 18 and 65 years old, from the same geographic region (Jiangsu Province), and had similar dietary backgrounds. Exclusion criteria included a history of autoimmune, metabolic, gastrointestinal, or genetic diseases, recent antibiotic/probiotic use, special diets, pregnancy, or major organ dysfunction. For the treatment group analysis, 13 GD patients were re-sampled after 3–5 months of Methimazole treatment, once their thyroid function had largely normalized.
Most important findings
The study found that patients with untreated GD exhibited significantly reduced gut microbiota alpha diversity (lower observed OTUs, Shannon, and Simpson indices) compared to healthy controls. The most notable microbial shifts at the genus level included significant increases in Lactobacillus, Veillonella, and Streptococcus in GD patients, with Blautia and Ruminococcus also elevated. Conversely, beneficial genera such as Phascolarctobacterium and Synergistetes were depleted in GD patients. After Methimazole treatment and restoration of thyroid function, gut microbial diversity improved, and the abundance of Blautia, Corynebacterium, Ruminococcus, and Streptococcus decreased, while Phascolarctobacterium increased.
Correlational analysis revealed that TRAb levels were positively associated with the abundance of Lactobacillus and Ruminococcus, and negatively associated with Synergistetes and Phascolarctobacterium. Synergistetes abundance was also negatively correlated with other thyroid autoantibodies (TGAb, TPOAb), suggesting a possibly protective role. Notably, changes in Ruminococcus and Phascolarctobacterium closely tracked changes in TRAb levels before and after treatment. The findings suggest that Ruminococcus and Lactobacillus may serve as novel microbial biomarkers for GD, while Synergistetes and Phascolarctobacterium may exert protective effects against thyroid autoimmunity.
Key implications
This study underscores a strong association between GD and gut microbiota dysbiosis, with specific microbial signatures correlating with disease activity and immune status. The depletion of potentially protective genera (Synergistetes, Phascolarctobacterium) and enrichment of taxa like Ruminococcus and Lactobacillus in GD patients are particularly relevant for microbiome signature databases. Importantly, restoration of euthyroid status partially normalizes the gut microbiota, implying that thyroid function and the gut microbiome are dynamically linked. These findings highlight the potential of targeting the gut microbiota for novel GD biomarkers or therapeutic interventions, though causality remains to be established. Further research with larger cohorts and mechanistic studies is warranted to clarify the role of gut microbes in GD pathogenesis and management.