PubMed · 2026-03-18
A water extract of Dendrobium orchid (a traditional medicinal herb) significantly reduced chronic fatigue symptoms in rats by rebalancing the gut microbiome and restoring the body's tryptophan metabolism — the same chemical pathway that influences mood, energy, and immune function in humans.
Rats treated with Dendrobium water extract at 0.4 g/kg for 4 weeks showed measurably improved swimming endurance and reduced depression-like behavior compared to untreated fatigued rats.
The extract significantly increased levels of four tryptophan-derived indole metabolites (IDN, IAA, IPA, IAld) linked to gut-brain signaling and immune regulation.
Three key enzymes in the kynurenine metabolic pathway (TDO2, KMO, KAT1) were upregulated in the liver, restoring downstream metabolite production that chronic fatigue had suppressed.
