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Crocin mitigated cognitive impairment and brain molecular alterations induced by different intensities of prenatal hypoxia in neonatal rats.

ABSTRACT:

Introduction

Brain hypoxia has important role to the onset and progression of sporadic form of Alzheimer disease via expression of hypoxia-inducible factor-1 (HIF-1). Crocin by anti-amyloidogenic property inhibits β-amyloid formation. However, the molecular mechanism associated with anti-amyloidogenic activity of crocin is unknown. So, the present study was designed to investigate the effect of crocin on cognitive behavior and expression of HIF-1α and β-secretase (BACE1) genes in the brain of neonate rats following different intensities of hypoxia during pregnancy.

Material and methods

Pregnant female rats were divided into six groups including sham, control crocin treated (CC), hypoxia with three different intensities (H1-H3), and most intense of hypoxic group treated with crocin (H3C) (30 mg/kg; i.p) at P14. Hypoxia induced on the 20th day of pregnancy. Animals in sham and CC were put in hypoxia chamber at the same time of hypoxia group without any hypoxia induction. Morris water maze (MWM) and qRT-PCR were used to evaluate the cognitive behavior and mRNA levels of BACE1 and HIF-1α genes in the brain tissues.

Results

Animal under 7% O₂ + 93% N₂ condition for 3 hr showed the highest cognitive behavior impairment and upregulated HIF-1α and BACE1 mRNA in brains of offspring (p < .001). Crocin treatment improved memory impairment and attenuated the gene expression of HIF-1α and BACE1 in the brains of neonate rat.

Conclusions

It was concluded that crocin has beneficial effects on the brain of neonate rats under gestational hypoxia by improvement of memory impairment and molecular alteration related to hypoxia.

SUBMITTER: Ghotbeddin Z

PROVIDER: S-EPMC8035433 | biostudies-literature |

REPOSITORIES: biostudies-literature

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