Targeting JAK2/STAT3-Dependent Macrophage Polarization by Chlorogenic Acid Attenuates Hepatic Inflammation in Chronic Stress

Chronic stress adversely affects and compromises physiological well-being in humans, inducing hepatic injury, with its pathogenesis mechanistically linked to alterations in macrophage polarization and the regulation of the inflammatory microenvironment. Chlorogenic acid (CGA), a principal active component of <i>Lonicera japonica</i> (honeysuckle), has been shown to have therapeutic effects on various liver diseases. However, the specific mechanism by which CGA confers hepatoprotective effects through the modulation of macrophage polarization and inflammatory responses remains unclear. In this study, rats were subjected to 6 h of daily restraint stress for 21 consecutive days, with the experimental group receiving concurrent administration of CGA (100 mg/kg, via gavage). The results demonstrated that CGA intervention effectively mitigated chronic stress-induced impairments in growth performance and hepatic structural and functional integrity. CGA significantly inhibited M1 macrophage polarization and the expression of pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α), while simultaneously promoting M2 polarization and the expression of the anti-inflammatory cytokine IL-10. Furthermore, the administration of CGA was found to inhibit the activation of the JAK2/STAT3 signaling pathway. Additionally, the use of the JAK2/STAT3 signaling pathway inhibitor, S3I-201, demonstrated effects similar to those observed with CGA treatment. In summary, CGA modulates macrophage polarization and the inflammatory response through the regulation of the JAK2/STAT3 signaling pathway, thereby mitigating the liver injury induced by chronic stress.