Gut-derived IL-17A via STAT3/RORγt signaling mechanistically bridges sleep deprivation and neuroinflammation-induced depression, and Schisandrin B exerts antidepressant-like effects by coordinating modulation of the gut-brain-immune network through inhibition of STAT3 phosphorylation and RORγt expression.
Key Findings
Results
Patients with circadian rhythm disorder-related depression showed elevated plasma IL-17A and systemic inflammatory cytokines alongside metabolic dysregulation.
Clinical analyses integrated plasma cytokine measurements and metabolite profiling from patients with circadian rhythm disorder-related depression.
Elevated IL-17A was identified as a key pro-inflammatory cytokine primarily derived from intestinal Th17 cells in these patients.
Systemic inflammatory cytokines beyond IL-17A were also elevated, suggesting broad neuroimmune dysregulation.
Metabolic dysregulation accompanied the inflammatory profile in affected patients.
Results
Sleep-deprived mice developed depressive-like behaviors associated with intestinal barrier disruption and Th17/IL-17A pathway activation.
A mouse model of sleep-deprivation-induced depression was employed to investigate neuroimmune and microbial alterations.
Behavioral tests confirmed depressive-like phenotypes in sleep-deprived animals.
Intestinal barrier disruption was documented alongside activation of the Th17/IL-17A pathway.
Abnormal resting-state fMRI (RS-fMRI) activity was detected in mood-regulating brain regions of sleep-deprived mice.
Western blotting and ELISA were used to confirm pathway activation at the protein level.
Results
Schisandrin B treatment markedly reversed depressive-like behaviors, gut barrier disruption, and IL-17A-driven inflammation in sleep-deprived mice.
Schisandrin B is a lignan derived from Schisandra chinensis.
Treatment restored gut microbial balance as assessed by 16S rDNA sequencing.
Intestinal barrier integrity was enhanced following Schisandrin B administration.
IL-17A-driven inflammation was suppressed and neural function was normalized as measured by RS-fMRI.
The reversal of changes was described as 'marked,' indicating substantial effect sizes.
Results
Schisandrin B mechanistically inhibited STAT3 phosphorylation and RORγt expression, targeting MAPK1 and GSK3β as key regulatory nodes.
STAT3 phosphorylation inhibition was identified as a primary molecular mechanism of Schisandrin B action.
RORγt expression, a transcription factor critical for Th17 cell differentiation, was reduced by Schisandrin B.
Network pharmacology combined with molecular docking identified MAPK1 and GSK3β as key regulatory targets.
These findings were integrated with multi-omics data to establish a mechanistic framework.
Results
Gut-derived IL-17A–STAT3/RORγt signaling was identified as a mechanistic bridge between sleep deprivation and central neuroinflammation.
The study provides 'direct evidence for the immunological basis of circadian rhythm-related depression.'
The pathway connects gut immune imbalance (Th17 cell activation) to central nervous system dysfunction via IL-17A.
Multi-omics approaches including gut microbiota sequencing, cytokine profiling, and neuroimaging (RS-fMRI) were integrated to validate the mechanism.
The authors describe this as the first demonstration that Schisandrin B exerts antidepressant-like effects via coordinated modulation of the gut-brain-immune network.
Results
Resting-state fMRI revealed abnormal neural activity in mood-regulating brain regions in sleep-deprived mice that was normalized by Schisandrin B.
RS-fMRI was employed to assess functional brain changes in the mouse model.
Mood-regulating brain regions specifically showed abnormal activity patterns following sleep deprivation.
Schisandrin B treatment normalized these neural function changes.
This represents integration of neuroimaging validation within a preclinical pharmacological study.
What This Means
This research suggests that disrupted sleep and circadian rhythms can trigger depression by setting off a chain reaction in the gut-brain axis. Specifically, sleep deprivation appears to damage the gut's protective barrier and shift immune cells in the intestine toward an inflammatory state, causing cells called Th17 cells to produce a protein called IL-17A. This protein travels from the gut to the brain and activates inflammatory pathways (involving molecules called STAT3 and RORγt), ultimately disrupting mood-regulating brain regions. The researchers observed these same elevated inflammatory markers in human patients with circadian rhythm-related depression, suggesting the findings may be relevant to people, not just mice.
The study also tested whether a natural compound called Schisandrin B — extracted from the plant Schisandra chinensis — could interrupt this harmful process. In sleep-deprived mice, Schisandrin B treatment reversed depressive-like behaviors, repaired the gut barrier, rebalanced the gut microbiome, reduced gut-derived IL-17A inflammation, and restored normal activity in mood-relevant brain areas as measured by brain imaging. At the molecular level, it worked by blocking specific inflammatory signaling proteins (STAT3 phosphorylation and RORγt), with two other proteins — MAPK1 and GSK3β — identified as additional targets through computational drug-target analysis.
This research suggests that the gut immune system plays a more direct role in sleep-deprivation-related depression than previously understood, and that targeting the gut-brain immune connection — rather than the brain alone — may be a viable therapeutic strategy. Schisandrin B is highlighted as a natural compound that could potentially address this gut-brain inflammatory pathway, though the findings are primarily from mouse models and further clinical research would be needed to establish its safety and effectiveness in humans.
Xu H, Qu K, Zhang Z, Wang Y, Zhao H, Fu J, et al.. (2026). Gut-derived IL-17A via STAT3/RORγt signaling underlies sleep disruption-induced depression: Targeting effects of Schisandrin B therapy.. Phytomedicine : international journal of phytotherapy and phytopharmacology. https://doi.org/10.1016/j.phymed.2026.158127