Pachymic Acid Promotes ILC2 Migration to the Brain via Dynein Axonemal Heavy Chain 9 Upregulation.

Researchers investigating traditional Chinese herbal medicine have discovered how Pachymic Acid (PA), a compound derived from Poria cocos (Fu Ling), may protect the brain after stroke. Using mouse models of stroke, scientists found that PA works through a fascinating gut-brain connection involving special immune cells called ILC2s.

The study showed that after a stroke, PA helps restore the intestinal barrier, which normally becomes damaged during brain injury. This intestinal protection reduces harmful inflammation throughout the body. More remarkably, PA促进 promotes the migration of beneficial ILC2 immune cells from the intestine to the injured brain tissue, where they help reduce inflammation and prevent brain cell death.

The research team discovered that PA works by increasing production of a protein called DNAH9, which appears essential for directing these protective immune cells to travel from the gut to the brain. Mice treated with PA before and after induced strokes showed significantly less brain damage, reduced inflammation, and better preservation of brain tissue compared to untreated animals.

This research provides scientific support for the traditional use of Poria cocos in treating neurological conditions and suggests potential new therapeutic approaches for stroke patients. The gut-brain axis—the communication pathway between intestinal and brain health—appears central to PA's protective effects. While this study was conducted in animals and human trials are needed, it offers promising evidence for herbal medicine's role in stroke recovery and highlights mechanisms that may be enhanced through acupuncture and integrated treatment approaches. Patients interested in exploring these therapies should consult with a qualified, licensed acupuncturist experienced in treating neurological conditions.

This preclinical study investigated Pachymic Acid's neuroprotective mechanisms in C57BL/6 mice subjected to Middle Cerebral Artery Occlusion/Reperfusion (MCAO/R). PA treatment pre- and post-injury significantly reduced cerebral inflammation and neuronal apoptosis while restoring intestinal barrier integrity and reducing systemic LPS levels. Critically, PA facilitated migration of intestinal type 2 innate lymphoid cells (ILC2s) to brain tissue, with peak accumulation at 6 hours post-MCAO/R following IL-33 activation. Transcriptomic analysis revealed PA reversed 24% of MCAO/R-induced aberrant gene expression. The mechanism involves upregulation of Dynein Axonemal Heavy Chain 9 (DNAH9); DNAH9 overexpression attenuated tissue damage, while knockdown abolished PA's protective effects. This research validates traditional applications of Poria cocos (Fu Ling) for cerebral ischemia and elucidates a novel gut-brain axis mechanism involving ILC2 trafficking. Findings support integrating PA-containing formulas in acute stroke protocols and suggest potential synergy with acupuncture's known effects on gut-brain signaling and neuroinflammation modulation.