Modulating the Gut-Brain Axis With Low-Level Laser Therapy (Pt. 2)

The Spleen and Stomach: The Epicenter of Postnatal Qi and Cognitive Stability

In TCM, the spleen and stomach constitute the foundation of postnatal qi production, orchestrating the transformation and transportation of nutrients essential for generating blood and qi. The spleen’s function of governing transportation and transformation directly influences cognitive acuity, with disruptions in spleen qi manifesting as diminished focus, memory impairment, and susceptibility to anxiety.

Pathological dampness, often a consequence of spleen qi deficiency or excess consumption of damp-producing foods, is traditionally described as “misting the mind,” a phenomenon analogous to contemporary descriptions of neuroinflammation arising from gut dysbiosis. Therapeutic interventions aimed at fortifying the spleen include acupuncture, herbal formulations such as Shen Ling Bai Zhu San, dietary modifications, and low-level laser therapy (LLLT).

The Liver: The Regulatory Mechanism of Qi Dynamics

The liver governs qi dynamics and emotional stability. Hepatic qi stagnation, frequently exacerbated by stress, parallels biomedical correlates of visceral hypersensitivity and IBS pathophysiology.

This pathology aligns with biomedical findings wherein stress-induced dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis alters gut microbiota composition and increases intestinal permeability. Interventions such as Xiao Yao San and acupuncture points including LR 3 (Taichong) and GB 34 (Yanglingquan) have been shown to mitigate the impact of liver qi stagnation on digestive and cognitive function.

The Heart: The Shen-Gut Connection

The heart houses the shen, governing mental clarity, cognition, and emotional stability. The heart-small intestine relationship, reflected in the fire element, underscores the bidirectional influence between emotional well-being and gut health. When heart qi or blood becomes deficient, patients may exhibit symptoms of insomnia, palpitations, anxiety, and digestive irregularities, particularly malabsorption syndromes linked to small intestine dysfunction.

Current research validates this connection by highlighting the influence of gut microbiota-derived neurotransmitters, such as serotonin and gamma-aminobutyric acid (GABA), on mental health. Acupuncture points like HT 7 (Shenmen) and PC 6 (Neiguan), combined with herbal formulas such as Tian Wang Bu Xin Dan, facilitate heart qi balance and harmonize the gut-brain axis.

The Kidneys: The Source of Essence and Neural Resilience

The kidneys, as the repository of jing (essence), play a pivotal role in neuroendocrine function and digestive vitality. Kidney essence depletion is often correlated with neurodegenerative conditions, cognitive decline, and chronic gastrointestinal disorders. The marrow generated by kidney essence nourishes the brain, aligning with biomedical perspectives on the role of adrenal function in sustaining cognitive and digestive resilience.

Kidney yin or yang deficiency can manifest as autonomic dysfunction, with symptoms such as constipation, fatigue, and impaired stress adaptation, paralleling contemporary understandings of dysautonomia and gut-brain axis dysfunction. Replenishing kidney qi through formulas such as Liu Wei Di Huang Wan, acupuncture, and adjunctive LLLT can significantly enhance both neurological and gastrointestinal integrity.

Many recent studies have examined TCM and the microbiota-gut-brain axis via metabolic, neuro-endocrine, autonomic nervous, and immune pathways.^7-9

Integrating LLLT Into TCM Practice for GBA Balance

LLLT can be seamlessly incorporated into acupuncture treatments to address imbalances along the gut-brain axis. By targeting specific acupuncture points, practitioners can enhance vagal tone, modulate inflammation and support organ function.

Auricular Stimulation: Vagal Modulation and Shen Regulation

• Shen Men: A key auricular point for regulating emotional balance, reducing stress and calming the shen, thereby mitigating gut dysregulation linked to stress-related disorders.
• Vagus Nerve Points: Situated in the cymba concha, these points provide direct access to vagal fibers, facilitating autonomic regulation, reducing systemic inflammation, and promoting parasympathetic dominance.

Abdominal Acupuncture: Gastrointestinal Regulation and Microbiome Support

• Ren 12 (Zhongwan): Strengthens spleen and stomach function, enhances digestive efficiency, and optimizes microbiome stability.
• Stomach 25 (Tianshu): Regulates intestinal motility, reduces inflammatory burden, and supports gut barrier integrity, essential for maintaining optimal gut-brain signaling.

Back-Shu Correspondences: Organ-Specific Modulation

• Bladder 20 (Spleen Shu): Augments digestive assimilation, fortifies mental clarity and modulates gut-derived neurotransmitter synthesis.
• Bladder 23 (Kidney Shu): Regulates adrenal function, mitigates HPA axis dysregulation and enhances stress resilience – key factors in gut-brain axis stability.

Hand and Foot Meridian Points: Systemic Integration and Immune Modulation

• Large Intestine 4 (Hegu): Influences gut-associated lymphoid tissue (GALT), modulates inflammatory responses and enhances intestinal immune function.
• Stomach 36 (Zusanli): Potentiates mitochondrial bioenergetics, supports digestive motility and bolsters systemic vitality, reinforcing gut-brain homeostasis.

Scalp Acupuncture System: Neurovascular Regulation and Cognitive Resilience

Transcranial LLLT research reveals its capacity to modulate neural plasticity, enhance cerebrovascular circulation, and attenuate neuroinflammation. By influencing key cortical and subcortical networks, scalp-point stimulation can optimize gut-brain connectivity and mitigate neurodegenerative progression.³

By strategically targeting these acupuncture points, LLLT synergizes with traditional interventions to amplify therapeutic outcomes, fostering an integrative approach to gut-brain axis regulation. This fusion of classical TCM principles with modern photobiomodulation techniques offers a powerful modality for addressing complex neurogastrointestinal disorders.

Research & Clinical Evidence

Emerging research underscores the efficacy of LLLT in modulating the GBA:

Gut Health: LLLT has been shown to reduce intestinal permeability (“leaky gut”), a condition linked to systemic inflammation and poor vagal tone.⁴

Mood Disorders: Clinical trials have demonstrated LLLT’s ability to alleviate depression and anxiety by stimulating the prefrontal cortex and vagus nerve.^1,5

Inflammatory Conditions: Studies highlight LLLT’s role in reducing pro-inflammatory cytokines, such as TNF-alpha and IL-6, which play a critical role in GBA dysfunction.⁶

Bridging Ancient Wisdom and Modern Science

The gut-brain axis embodies a sophisticated network of organ interrelations, each playing a crucial role in maintaining physiological equilibrium. By integrating classical diagnostics with modern therapeutic modalities such as low-level laser therapy, acupuncture, and targeted herbal formulations, practitioners can optimize gut-brain homeostasis, fostering enhanced cognitive function, emotional resilience and digestive health.

Notably, low-level laser therapy (LLLT) can provide a synergistic response, augmenting the efficacy of acupuncture and herbal interventions by enhancing cellular function, reducing inflammation and accelerating tissue repair.

This holistic approach underscores the enduring relevance of TCM in addressing complex, multifaceted conditions affecting both neurological and gastrointestinal systems.

For patients with chronic conditions such as IBS, anxiety or autoimmune disorders, this integrative approach provides a powerful framework for healing. Future research and collaboration will undoubtedly expand the applications of LLLT in clinical practice, reinforcing the timeless principles of TCM while embracing cutting-edge science.

Editor’s Note: Part 1 of this article appeared in the May 2025 issue.

References

1. Sancho-Balsells A, Borràs-Pernas S, Flotta F, et al. Brain-gut photobiomodulation restores cognitive alterations in chronically stressed mice through the regulation of Sirt1 and neuroinflammation. J Affect Disord, 2024;354:574-588.
2. Eberhardt A, Sammons T. Exploring a novel approach using red and violet laser therapy for carotid artery stenosis – a case series. Recent Adv Clin Trials, 2024;4(2):1-6.
3. Lin H, Li D, Zhu J, et al. Transcranial photobiomodulation for brain diseases: review of animal and human studies including mechanisms and emerging trends. Neurophotonics, 2024;11(1):010601.
4. Bicknell B, Liebert A, McLachlan CS, Kiat H. Microbiome changes in humans with Parkinson’s disease after photobiomodulation therapy: a retrospective study. J Personalized Med, 2022;12(1):49.
5. Shahdadian S, Wang X, Liu H. Directed physiological networks in the human prefrontal cortex at rest and post transcranial photobiomodulation. Scientific Rep, 2024;14(1):10242
6. Sammons T, Shanks S. Efficacy of red low-level laser for postoperative pain management: a review of literature. J Perioperative Pract, 2023;33(11):350-357.
7. Yaklai K, Pattanakuhar S, Chattipakorn N, Chattipakorn SC. The role of acupuncture on the gut-brain-microbiota axis in irritable bowel syndrome. Am J Chinese Med, 2021;49(2):285-314.
8. Lv Z, Liu R, Su K, et al. Acupuncture ameliorates breast cancer-related fatigue by regulating the gut microbiota-gut-brain axis. Front Endocrinol, 2022;13:921119.
9. Guo J, Guo J, Rao X, et al. Exploring the pathogenesis of insomnia and acupuncture intervention strategies based on the microbiota-gut-brain axis. Front Microbiol, 2024;15:1456848.