# Modulation of the lncRNA TCONS_00265853-miR-421-5p-CLOCK axis by Ziyin Buyang Formula in polycystic ovarian syndrome with circadian rhythm disruption: an integrated bioinformatics and experimental approach

## TL;DR

This study shows how a traditional Chinese medicine formula helps treat PCOS by restoring disrupted circadian rhythms through a specific molecular pathway.

## Contribution

The study identifies a novel lncRNA-miRNA-CLOCK axis modulated by Ziyin Buyang Formula in PCOS with circadian disruption.

## Key findings

- Circadian disruption in PCOS downregulates TCONS_00265853 and CLOCK while upregulating miR-421-5p.
- ZYBYF treatment restores the lncRNA-miR-421-5p-CLOCK axis and suppresses MAPK activation in PCOS rats.
- ZYBYF improves hormonal profiles and ovarian morphology by modulating circadian-related pathways.

## Abstract

Polycystic ovarian syndrome (PCOS), a common endocrine disorder in reproductive-aged women, is linked to circadian rhythm disruption, but the molecular mechanisms remain unclear. Dysregulation of the lncRNA TCONS_00265853-miR-421-5p-CLOCK axis may play an important role. Ziyin Buyang Formula (ZYBYF), a Traditional Chinese Medicine (TCM) targeting kidney Yin-Yang balance, shows therapeutic potential, though its mechanism is unclear. This study explores ZYBYF’s role in modulating this axis to improve circadian-disrupted PCOS.

Network pharmacology identified ZYBYF’s bioactive components and targets, integrated with PCOS-associated genes and circadian disruption-related differentially expressed genes (DEGs) from ovarian tissues. A continuous light-induced PCOS rat model (10-week 24-h light exposure) was employed to validate ZYBYF’s effects. Interventions included ZYBYF treatment.

Bioinformatics identified 25 intersection targets, with MAPK signaling as the central pathway. In vivo, circadian disruption downregulated lncRNA TCONS_00265853 and CLOCK, elevated miR-421-5p, and hyperactivated MAPK (p-p38, p-ERK1/2, p-JNK), exacerbating ovarian apoptosis (↑BAX, ↓Bcl-2, p < 0.001). ZYBYF restored circadian axis components (↑TCONS_00265853, CLOCK; ↓miR-421-5p), suppressed MAPK activation, and normalized ovarian morphology and hormonal profiles (↓LH, T, ACTH; ↑E2, FSH, p < 0.001). PRKCA expression, a MAPK regulator, was rescued by ZYBYF, counteracting dysregulation of IL1B, VEGFA, and TGFB1.

Circadian disruption exacerbates PCOS via the TCONS_00265853-miR-421-5p-CLOCK axis, driving MAPK hyperactivation and ovarian apoptosis. ZYBYF reverses these effects, restoring hormonal balance and follicular dynamics. This study provides mechanistic validation of ZYBYF’s efficacy, positioning it as a promising therapeutic strategy for circadian-disrupted PCOS. These findings suggest that ZYBYF may modulate circadian rhythm–related pathways in PCOS via the lncRNA–miRNA–CLOCK axis, warranting further mechanistic validation.