---
title: "Pregnancy Alters Maternal Sleep and Modulates Kynurenine Pathway Effects in Female Rats"
id: "biorxiv-13-pregnancy-impacts-maternal-sleep-focus-on-kynurenine-pathway-activation-in"
canonical_url: "https://medichelpline.com/clinical-feed/biorxiv-13-pregnancy-impacts-maternal-sleep-focus-on-kynurenine-pathway-activation-in"
content_type: "clinical_feed_article"
specialty: "Pharmacology"
source_name: "bioRxiv (Biomedical Preprints)"
source_url: "https://www.biorxiv.org/content/10.64898/2026.09.14.751544v1?rss=1"
published_at: "2026-09-21T12:00:00.000Z"
evidence_level: "Verified Feed"
license: "CC-BY-NC-4.0 / Informational Use"
---
# Pregnancy Alters Maternal Sleep and Modulates Kynurenine Pathway Effects in Female Rats
## Provenance & Clinical Metadata
- **Canonical URL:** https://medichelpline.com/clinical-feed/biorxiv-13-pregnancy-impacts-maternal-sleep-focus-on-kynurenine-pathway-activation-in
- **Specialty:** [Pharmacology](https://medichelpline.com/clinical-feed/pharmacology.md)
- **Primary Source:** bioRxiv (Biomedical Preprints)
- **Source URL:** [Original Journal Publication](https://www.biorxiv.org/content/10.64898/2026.09.14.751544v1?rss=1)
- **Published At:** 2026-09-21T12:00:00.000Z
- **Evidence Rating:** Verified Feed
## Executive GIST (TL;DR)
- Study used an embryonic kynurenine (EKyn) dietary model to amplify **kynurenine** pathway (KP) metabolism by supplementing maternal diet with kynurenine during the final gestational week. - Within-subject design compared sleep-wake architecture in the same female rats when pregnant and when non-pregnant, and evaluated brain and salivary levels of **kynurenic acid (KYNA)**. - In control-fed pregnant dams (ECon), **pregnancy** increased dark-phase NREM and REM sleep relative to non-pregnant baseline. - EKyn dams largely maintained the pregnancy-associated increases in dark-phase NREM and REM, but exhibited a specific reduction in light-phase REM sleep near parturition that was not seen in ECon dams. - In non-pregnant females, dietary kynurenine produced a more consistent phenotype: it reduced light-phase REM sleep across treatment days. - During pregnancy, kynurenine-related sleep effects were less apparent and were detectable primarily when compared to the animals' own non-pregnant baseline rather than against pregnant controls. - Salivary KYNA levels differentiated kynurenine-fed females from matched controls and correlated with brain KYNA, suggesting saliva as a potential peripheral marker of central KP activation. - Authors conclude that **pregnancy** reshapes sleep-wake architecture and attenuates but does not eliminate KP-associated REM sleep disruption, implicating elevated brain **KYNA** in maternal sleep regulation. - This work is a preprint and has not been peer reviewed; funding sources include NIH grants and the American Academy of Sleep Medicine Foundation.
## Clinical Analysis & Structured Key Points
Pregnancy Impacts Maternal Sleep: Focus on Kynurenine Pathway Activation in Female Rats | bioRxiv Skip to main content New Results Pregnancy Impacts Maternal Sleep: Focus on Kynurenine Pathway Activation in Female Rats Courtney J Wright , Maria V Piroli , J Hunter Cox , Homayoun Valafar , Norma Frizzell , View ORCID Profile Ana Pocivavsek doi: https://doi.org/10.64898/2026.09.14.751544 Courtney J Wright 1 Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina Floyd School of Medicine, Columbia, SC 29209, USA; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Maria V Piroli 1 Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina Floyd School of Medicine, Columbia, SC 29209, USA; Find this author on Google Scholar Find this author on PubMed Search for this author on this site J Hunter Cox 1 Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina Floyd School of Medicine, Columbia, SC 29209, USA; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Homayoun Valafar 2 Department of Computer Science and Engineering, University of South Carolina Molinaroli College of Engineering and Computing, Columbia, SC 29201, USA Find this author on Google Scholar Find this author on PubMed Search for this author on this site Norma Frizzell 1 Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina Floyd School of Medicine, Columbia, SC 29209, USA; Find this author on Google Scholar Find this author on PubMed Search for this author on this site Ana Pocivavsek 1 Department of Pharmacology, Physiology, and Neuroscience, University of South Carolina Floyd School of Medicine, Columbia, SC 29209, USA; Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Ana Pocivavsek For correspondence: ana.pocivavsek{at}uscmed.sc.edu Abstract Info/History Metrics Supplementary material Preview PDF Abstract Study Objectives: Poor maternal sleep is associated with adverse health outcomes for women and their offspring, and perturbations to tryptophan metabolism through the kynurenine pathway (KP) may contribute. Kynurenic acid (KYNA), a neuroactive KP metabolite and endogenous modulator of glutamatergic and cholinergic neurotransmission, is of particular interest because elevated KYNA has been linked to altered sleep-wake behavior and neurodevelopmental outcomes. Because sleep patterns and KP metabolism change during pregnancy, we tested whether pregnancy modifies the effects of kynurenine supplementation on sleep-wake architecture. Methods: To model enhanced KP metabolism, we used the embryonic kynurenine (EKyn) model, in which the maternal diet is supplemented with kynurenine, the initial KP metabolite, during the last week of gestation. Using a within-subject design, we evaluated sleep-wake parameters in pregnant and non-pregnant female rats and assessed KYNA in brain and saliva. Results: Pregnancy increased dark phase NREM and REM sleep in control-fed (ECon) dams, a pattern largely maintained in EKyn dams. However, near parturition, EKyn dams exhibited reduced light phase REM sleep that was not observed in controls. In non-pregnant females, kynurenine supplementation produced a stronger phenotype, consistently reducing light phase REM sleep across treatment days. During pregnancy, kynurenine-associated sleep effects were detectable only when compared to within-subject non-pregnant baseline. Salivary KYNA distinguished kynurenine-fed females from matched controls and correlated with brain KYNA levels. Conclusion: These findings show that pregnancy reshapes sleep-wake architecture and attenuates, but does not eliminate, kynurenine-associated REM sleep disruption, implicating KP metabolism and potentially elevated brain KYNA in maternal sleep regulation. Competing Interest Statement The authors have declared no competing interest. Funder Information Declared National Institutes of Health, https://ror.org/01cwqze88 , R01 HL174802 , P20GM103499 American Academy of Sleep Medicine Foundation, https://ror.org/057zq8s17 , 301-BS-23 Copyright The copyright holder for this preprint is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. Back to top Previous Next Posted September 21, 2026. Download PDF Supplementary Material Email Thank you for your interest in spreading the word about bioRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. 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Share Pregnancy Impacts Maternal Sleep: Focus on Kynurenine Pathway Activation in Female Rats Courtney J Wright , Maria V Piroli , J Hunter Cox , Homayoun Valafar , Norma Frizzell , Ana Pocivavsek bioRxiv 2026.09.14.751544; doi: https://doi.org/10.64898/2026.09.14.751544 Share This Article: Copy Citation Tools Pregnancy Impacts Maternal Sleep: Focus on Kynurenine Pathway Activation in Female Rats Courtney J Wright , Maria V Piroli , J Hunter Cox , Homayoun Valafar , Norma Frizzell , Ana Pocivavsek bioRxiv 2026.09.14.751544; doi: https://doi.org/10.64898/2026.09.14.751544 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Areas All Articles Animal Behavior and Cognition (8015) Biochemistry (18744) Bioengineering (14890) Bioinformatics (44453) Biophysics (22610) Cancer Biology (19728) Cell Biology (26906) Clinical Trials (138) Developmental Biology (13970) Ecology (21008) Epidemiology (2067) Evolutionary Biology (25457) Genetics (16171) Genomics (23513) Immunology (18717) Microbiology (42520) Molecular Biology (18064) Neuroscience (93479) Paleontology (700) Pathology (2982) Pharmacology and Toxicology (5100) Physiology (8116) Plant Biology (16000) Scientific Communication and Education (2095) Synthetic Biology (4560) Systems Biology (10237) Zoology (2391)
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