Title:	The impact of melatonin on cellular dynamics and gene expression of bovine embryos cultured under low and high oxygen tension.
Authors:	OLIVEIRA, I. R. dos S. MARTINS, C. F. RODRIGUES, F. L. MELLO, V. C. RODRIGUES, M. T. de O. FARIA, L. C. de AMARAL, H. B. S. ANDRADE, R. V. de FONSECA, M. J. P. DODE, M. A. N. BÁO, S. N.
Affiliation:	ISABELLA RODRIGUES DOS SANTOS OLIVEIRA, UNIVERSIDADE DE BRASÍLIA; CARLOS FREDERICO MARTINS, CPAC; FABIANA LIMA RODRIGUES, CENTRO UNIVERSITÁRIO ICESP; VICTOR CARLOS MELLO, UNIVERSIDADE DE BRASÍLIA; MARIA TEREZA DE OLIVEIRA RODRIGUES, UNIVERSIDADE DE BRASÍLIA; LUCAS COSTA DE FARIA, UNIVERSIDADE DE BRASÍLIA; HALLYA BEATRIZ SOUSA AMARAL, UNIVERSIDADE CATÓLICA DE BRASÍLIA; ROSÂNGELA VIEIRA DE ANDRADE, UNIVERSIDADE CATÓLICA DE BRASÍLIA; MARCIO JOSÉ POÇAS FONSECA, UNIVERSIDADE DE BRASÍLIA; MARGOT ALVES NUNES DODE, CENARGEN; SÔNIA NAIR BÁO, UNIVERSIDADE DE BRASÍLIA.
Date Issued:	2026
Citation:	Molecular Reproduction and Development, v. 93, n. 4, e70102, 2026.
Description:	This study investigated the effects of melatonin supplementation in the culture medium on the development, cellular dynamics and gene expression of bovine embryos produced in vitro under low (5%) or high (20%) oxygen tension. Zygotes were cultured without melatonin or with (10−9 M), and cleavage, blastocyst rates, blastomere number, apoptosis, mitochondrial activity, lipid accumulation, and expression of genes related to metabolism, oxidative stress and embryo quality were evaluated. Under high O₂ tension, melatonin increased blastocyst rate (39.8% vs. 34.0%), raised blastomere number, reduced apoptosis, and decreased lipid accumulation. It also upregulated SOD2, KRT8, IFN-τ, and PLAC8. Under low O₂ tension, melatonin increased cleavage rate and mitochondrial activity but did not affect blastocyst rate; only SOD2 was upregulated. Embryos cultured without melatonin under low O₂ showed higher IFN-τ and PLAC8 expression. In conclusion, melatonin improves embryo quality and viability mainly under high oxygen tension, acting as an antioxidant, gene modulator and apoptosis inhibitor. Its effects are more limited under low O2, likely because this environment is closer to physiological conditions and requires fewer responses to oxidative stress.
Thesagro:	Bovino Embrião Animal
NAL Thesaurus:	Apoptosis Cattle Embryo (animal) Gene expression Melatonin Oxidative stress
Keywords:	Melatonina Expressão gênica
DOI:	https://doi.org/10.1002/mrd.70102
Type of Material:	Artigo de periódico
Access:	openAccess
Appears in Collections:	Artigo em periódico indexado (CPAC)