Dr. Sagam Dinesh Reddy¹*, Dr. Sateesh Babu Kaki², Dr. Sarath Chandra Nibhanpudi³

¹MD (Physician), DFM (Family Medicine), DICMH/CCPMH (NIMHANS Bangalore), PGPN (Boston University USA), AFIH (RLI Kanpur / DGFASLI Govt of India),

Director, LMR Hospital, G Konduru, NTR District, Andhra Pradesh – 521229, India.

ORCID: [0000-0001-7659-9441] Email: dineshsagam143@gmail.com

²Assistant Professor, Department of Biochemistry, GSL Medical College and Hospital, Rajahmundry, Andhra Pradesh, India. ORCID: [0009-0000-2952-5538]

³Assistant Professor, Department of Pharmacology, Sri Venkateswara Institute of Medical Sciences (SVIMS), Tirupati, Andhra Pradesh, India. ORCID: [0009-0009-9671-5505]

Corresponding Author: Dr. Sagam Dinesh Reddy, LMR Hospital, G Konduru, NTR District, Andhra Pradesh, India, 521229, ORCID: [0000-0001-7659-9441].

Citation: Dr. Sagam Dinesh Reddy, Dr. Sateesh Babu Kaki, Dr. Sarath Chandra Nibhanpudi (2025) Systematic Review and Meta-Analysis of the Effects of Endocrine Disrupting Chemicals on Circadian Clock Gene Expression. Int J Fam Med Pub Health, 4(2);1-4.

Copyrights: © 2025, S. Dinesh Reddy, This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

Abstract:

Background: Endocrine-disrupting chemicals (EDCs) such as bisphenol A (BPA), PFOS, PCBs, DEHP, and dioxins are known to interfere with hormonal systems. Emerging evidence suggests that EDCs can also disrupt circadian rhythm by altering the expression of core clock genes like BMAL1, PER1, CRY1, and CLOCK. However, no prior meta-analysis has comprehensively quantified this impact across multiple biological models. Objective: To systematically review and meta-analyze the effects of EDC exposure on circadian clock gene expression across human, animal, and in vitro studies. Methods: This review followed a PROSPERO-registered protocol (CRD420251068975). Databases searched included PubMed, Scopus, GEO, and ToxNet from January 2000 to June 2025. Inclusion criteria encompassed in vivo, in vitro, or epidemiological studies reporting gene expression data for BMAL1, PER1, CRY1, and CLOCK after EDC exposure. Random-effects meta-analysis was performed using standardized mean differences (SMDs). Risk of bias was assessed using OHAT and the Newcastle–Ottawa Scale. Results: From 342 screened records, 19 studies met inclusion criteria, and 10 were eligible for meta-analysis. EDC exposure was associated with significant downregulation of circadian genes, particularly BMAL1 and PER1. The pooled effect size was SMD = –0.48 (95% CI: –0.59 to –0.37; p < 0.001), with moderate heterogeneity (I² = 41%). Funnel plots showed no substantial publication bias. Conclusion: This meta-analysis demonstrates consistent and statistically significant suppression of core circadian genes by chronic EDC exposure. These findings highlight the importance of including chronodisruption markers in toxicological and occupational health surveillance frameworks.