Gut Microbiota in the Treatment of Migraine with Acupuncture: A Review

This comprehensive review examines an emerging and fascinating field of medicine: how acupuncture treats migraine through modulation of the gut microbiota and the microbiota-gut-brain axis (MGBA). Migraine, which affects approximately 14.4% of the world's population and is the second most common neurological disorder, has traditionally been viewed as a purely neurological condition. However, growing evidence reveals a complex connection between gut health and migraine attacks.

Research shows that patients with migraine display a consistent pattern of gut microbiota imbalance, characterized by decreased microbial diversity, reduced beneficial bacteria such as Faecalibacterium (a producer of anti-inflammatory short-chain fatty acids), and increased pro-inflammatory bacteria such as Veillonella. This imbalance triggers a cascade of pathological events: harmful bacteria produce lipopolysaccharides (LPS) that damage the intestinal barrier, allowing toxins to enter the bloodstream. These toxins then activate the immune system, generating pro-inflammatory cytokines such as IL-6 and TNF-alpha, which can cross the blood-brain barrier and activate the trigeminovascular system, triggering migraine attacks.

The enteric nervous system also plays a crucial role, with microbiota imbalance leading to abnormal neurotransmitter production. Reduced GABA synthesis (due to a decrease in Lactobacillus and Bifidobacterium) impairs neural inhibitory function, while alterations in tryptophan metabolism affect serotonin levels and may generate neurotoxic substances that increase neuronal excitability.

Acupuncture emerges as a multidimensional therapeutic intervention that acts through several interconnected mechanisms. First, studies show that acupuncture at specific points such as Zusanli (ST-36), Sanyinjiao (SP-6), and Baihui (GV-20) significantly increases alpha diversity of the microbiota, restoring intestinal ecological balance. The technique promotes the growth of beneficial short-chain fatty acid-producing bacteria while reducing the abundance of LPS-producing pathogenic species such as Proteobacteria and Escherichia coli-Shigella.

Second, acupuncture strengthens intestinal barrier integrity through upregulation of tight junction proteins, including ZO-1, occludin, and claudin-1. This restoration of the physical barrier prevents translocation of endotoxins and pro-inflammatory factors into the systemic circulation, interrupting the inflammatory cascade that contributes to migraine attacks.

Third, acupuncture modulates the hypothalamic-pituitary-adrenal (HPA) axis, reducing levels of cortisol and corticotropin-releasing hormone, which decreases oxidative stress and the systemic inflammatory response. This modulation also reduces emotional triggers of migraine, such as anxiety and stress.

Fourth, through regulation of the microbiota, acupuncture optimizes the production of neuroprotective metabolites. Increased production of short-chain fatty acids not only protects the intestinal barrier but also exerts direct anti-inflammatory effects on the central nervous system, promotes neurogenesis, and increases brain-derived neurotrophic factor (BDNF) production.

The clinical implications are significant. This research suggests that acupuncture offers a holistic approach to treating migraine, addressing not only neurological symptoms but also the underlying causes related to gut health. Unlike conventional medications, which often have side effects and dependence potential, acupuncture offers a safe, multitarget alternative.

For patients with migraine who also present with gastrointestinal symptoms—a common comorbidity—acupuncture may offer dual benefits, improving both intestinal function and reducing the frequency and intensity of migraine attacks.

Limitations include the need for more large-scale randomized clinical trials and studies on standardized treatment protocols. Future research should explore combinations of acupuncture with probiotics/prebiotics and investigate differences in response across migraine subtypes.