UNDERSTANDING THE GUT MICROBIOME'S ROLE IN ROSACEA
Is Rosacea A Gut Issue?
Rosacea, a chronic skin condition characterized by facial redness, visible blood vessels, and sometimes pimples or bumps, affects millions worldwide. While its exact cause remains unclear, emerging research points towards a potential link between rosacea and the gut microbiome. Understanding this connection could offer new insights into managing this condition.
Rosacea treatment usually depends on topical antibiotics and avoids several factors that can trigger inflammation, such as heat, sunlight, spicy foods, alcohol, and histamine-rich foods, which can alter the skin’s epidermal barrier function or disrupt immune function. However, the gut microbiota affects the skin more directly. In the case of an impaired intestinal barrier, intestinal bacteria and their metabolites can enter the bloodstream, accumulate in the skin, and disrupt the skin microbiome. Healing the gut has the potential to heal rosacea.
The Link Between Gut Health and Rosacea
The gut microbiome, a complex ecosystem of trillions of bacteria, viruses, fungi, and other microorganisms residing in our gastrointestinal tract, plays a fundamental role in maintaining overall health. Its influence extends beyond digestion, including the immune system, hormones, and mental health. Research studies have shown a relationship between gut dysbiosis – an imbalance in gut microbes – and various aspects of health, including inflammatory skin conditions like rosacea. Imbalances in the gut microbiota can stimulate systemic inflammation and compromise the body's immune response, potentially contributing to the onset and severity of rosacea flare-ups.
Although the exact pathophysiology of rosacea is debated, present theories implicate dysregulation of innate and adaptive immunity, aberrant neurovascular signaling, chronic inflammation, and the overgrowth of commensal skin organisms.1 The generation of reactive oxygen species (ROS) due to an altered innate immune response appears to be a component of rosacea’s mechanism of disease, as studies have demonstrated higher levels of ROS in patients with this condition.1
Understanding the Mechanisms: How Gut Microbes Affect Rosacea
Inflammation: Imbalances in gut bacteria, known as dysbiosis, can lead to increased intestinal permeability, allowing harmful substances to leak into the bloodstream, known as "leaky gut." This triggers an inflammatory response that might contribute to the skin inflammation characteristic of rosacea.
Immune System Dysregulation: The gut microbiome plays a pivotal role in regulating the immune system. Imbalances can disrupt immune function, potentially leading to increased sensitivity and reactivity in the skin, contributing to rosacea symptoms.
Triggers and Flare-Ups: Certain foods or environmental factors can influence gut health and trigger rosacea flare-ups. For instance, food sensitivities or allergies may exacerbate gut dysbiosis, subsequently impacting the skin.
Microbial Metabolites: Gut microbes produce metabolites that can influence various physiological processes, including skin health. Short-chain fatty acids produced by gut bacteria may affect skin function and inflammation.
Helicobacter pylori infection (HPI): HPI has been associated with rosacea. Helicobacter pylori is a bacteria that infects the stomach and can damage the tissue in the stomach and the first part of the small intestine (the duodenum). This causes gastric mucosal inflammation by increasing reactive oxygen species (ROS), specifically nitric oxide. Nitric oxide causes inflammation of the gut mucosa and alters the skin’s physiological processes, such as vasodilation, inflammation, and immune regulation.2 Another mechanism justifying the role of H. pylori in rosacea development is the production of a cytotoxin, which induces the production of pro-inflammatory cytokines such as TNF-α and IL-8.3 As a result of these inflammatory cytokine releases, inflammation of gastric mucosa and clinical manifestation of rosacea are seen.3 H. pylori can be diagnosed with noninvasive urea breath tests, stool antigen tests, and serum/urine antibody tests. The urea breath test, in particular, has a high reported sensitivity and specificity.4
SIBO: The prevalence of small intestinal bacterial overgrowth (SIBO) is increased in rosacea patients.5 Circulating cytokines, particularly TNF-α, may play a role in the increased prevalence of rosacea. One study showed that treating SIBO with antibiotics in 40 patients led to remission of rosacea in all cases.4 The remission persisted in the majority of patients at the three-year follow-up.4 SIBO has also been linked to decreased gut motility. In one case study, a high-fiber intervention improved rosacea.4 SIBO can be detected using a lactulose and glucose H2/CH4 breath test.
Gut Health for Rosacea Management
Probiotics: These beneficial bacteria supplements may help restore microbial balance in the gut and alleviate inflammation, potentially reducing rosacea symptoms. Strains like lactobacillus and bifidobacterium have shown promise in some studies. A combination of topical and oral probiotic treatment may be the most effective.2 Treatment with probiotics may improve skin barrier function, reduce inflammation, and reduce the dysregulation of the skin microbiome by restoring a healthy balance of cytokines.2 For example, toll-like receptor 2 (TLR2) may be upregulated in rosacea and could be a probiotic target.2 Bacillus subtilis-3 is effective against H. pylori, allowing spore colonization of the gastrointestinal system and altering the mucosal barrier microbiome, thereby eradicating H. pylori to reduce rosacea symptoms and associated gastrointestinal problems.3
Diet and Lifestyle Modifications: Adopting a balanced diet rich in fiber, antioxidants, and fermented foods, such as yogurt, kefir, miso, kimchi, and sauerkraut can support a healthy gut microbiome. Avoiding potential trigger foods, such as alcohol, and managing stress levels may also positively impact both gut health and rosacea symptoms.
Personalized Approaches: Each individual’s experience with rosacea is unique. Tailoring treatments based on an individual's gut microbiome composition could be the future of rosacea management. Analyzing an individual's gut flora and customizing therapies may lead to more effective and personalized interventions.
The Road Ahead
As research on the gut-skin axis continues to evolve, the potential for harnessing gut health interventions in managing rosacea is promising. However, it's crucial to acknowledge that more extensive, well-designed studies are needed to fully understand the complexities of this relationship and its practical implications for rosacea treatment.
REFERENCES
1.Daou H, Paradiso M, Hennessy K, Seminario-Vidal L. Rosacea and the Microbiome: A Systematic Review. Dermatol Ther (Heidelb). 2021;11(1):1-12. doi:10.1007/s13555-020-00460-1. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7859152/.
2.Zhu W, Hamblin MR, Wen X. Role of the skin microbiota and intestinal microbiome in rosacea. Front Microbiol. 2023;14:1108661. Published 2023 Feb 10. doi:10.3389/fmicb.2023.1108661. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9950749/#:~:text=In%20rosacea%20patients'%20intestinal%20bacterial,Nakatsuji%20and%20Gallo%2C%202012).
3.Mahmud MR, Akter S, Tamanna SK, et al. Impact of gut microbiome on skin health: gut-skin axis observed through the lenses of therapeutics and skin diseases. Gut Microbes. 2022;14(1):2096995. doi:10.1080/19490976.2022.2096995. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9311318/.
4.Weiss E, Katta R. Diet and rosacea: the role of dietary change in the management of rosacea. Dermatol Pract Concept. 2017;7(4):31-37. Published 2017 Oct 31. doi:10.5826/dpc.0704a08. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5718124/.
5.De Pessemier B, Grine L, Debaere M, Maes A, Paetzold B, Callewaert C. Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions. Microorganisms. 2021;9(2):353. Published 2021 Feb 11. doi:10.3390/microorganisms9020353. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7916842/#:~:text=Gut%20and%20skin%20dysbiosis%20are,whereas%20crosstalk%20can%20be%20bidirectional