Investigating the Relationship between Hippocampal BDNF Gene Expression and Spatial Memory in the Open Field Test in Offspring Born from Rats Treated with Ethanol

Subject Areas : Journal of Chemical Health Risks

Mousa Shaabani Ghahremanlo ¹ , Vida Hojati ² , Gholamhasan Vaezi ³ , Shahram Sharafi ⁴

1 - Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran
2 - Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran
3 - Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran
4 - Department of Biology, Damghan Branch, Islamic Azad University, Damghan, Iran

Received: 2023-06-15 Accepted : 2023-08-14 Published : 2024-03-01

Keywords: Learning, ethanol, Memory, Brain-Derived Neurotrophic Factor, Fetal alcohol syndrome,

Abstract :

Alcohol consumption during pregnancy causes damage to the mother and the developing fetus, especially the central nervous system. Exposure of pregnant mothers to ethanol activates cell death pathways and interferes in the expression of neurotrophic factors and spatial memory of children. The aim of this study is to investigate the relationship between hippocampal BDNF gene expression and spatial memory in the offspring of pregnant rats treated with ethanol, and which period of pregnancy the hippocampus suffers more damage from ethanol consumption. The pregnant rats were randomly divided into five groups (six in each group): the control group (received distilled water only) and four treatment groups that received ethanol (20%, 4.5 g kg^-1) by oral gavage, in the first 5 days, the first decade, the second decade and the entire period of pregnancy, respectively. The half of offspring was sacrificed on the 30th day after birth according to ethical principles, and their hippocampal brain tissue was extracted. The other half of the children, who were not victims, were subjected to a behavioral test of spatial memory and cognitive memory using the open field test, 24 hours later. BDNF gene expression was measured by RT-PCR method. The mixture of 1 microgram of RNA and 1 microliter of cDNA synthesis primer was incubated for 5 minutes at 70 degrees. Then 2 microliters of nucleotide mixture, 4 microliters of reverse transcriptase enzyme buffer, 1 microliter of reverse transcriptase enzyme, 1 microliter of RNase inhibitor protein were added and incubated for 10 minutes at 25 degrees, one hour at 42 degrees, and 10 minutes at 70 degrees. For data analysis, SPSS and Excel Softwares and one-way ANOVA and Tukey tests were used. The results showed that ethanol administration during pregnancy induced spatial memory disorder (p < 0.001). Alcohol consumption during rat pregnancy led to fetal growth and development disorders and disorders related to learning and spatial and cognitive memory in children, which had the most adverse effects in the treated groups in the second decade and the entire period of pregnancy. It can be concluded that this part of the nervous system during this period of pregnancy suffers more damage from alcohol consumption.

References:

1. Pierrefiche O., 2017. Long term depression in rat hippocampus and the effect of ethanol during fetal life. Brain Sciences. 7(12), 157.


2. Farhadi L., Hojati V., Khaksari M., Vaezi G., 2022. The effect of crocin on cognition and necrosis cell death in the hippocampus area in the model of fetal alcohol spectrum disorders in male rats. Journal of Animal Environment. 14(3), 103-110.


3. Jafari M., Hojati V., Khaksari M., Vaezi G., 2022. Effect of simvastatin on memory disorders and Hippocampal cell death in the model of the fetal alcoholic syndrome in male rats. Koomesh. 24(6), 826-834.


4. Heller M., Burd L., 2014. Review of ethanol dispersion, distribution, and elimination from the fetal compartment. Birth Defects Research Part A: Clinical and Molecular Teratology. 100(4), 277-283.


5. Popova S., Lange S., Probst C., Gmel G., Rehm J., 2018. Global prevalence of alcohol use and binge drinking during pregnancy, and fetal alcohol spectrum disorder. Biochemistry and Cell Biology. 96(2), 237-240.


6. Popova S., Dozet D., Shield K., Rehm J., Burd L., 2021. Alcohol's Impact on the Fetus. Nutrients. 13(10), 3452.


7. Burden M.J., Westerlund A., Muckle G., Dodge N., Dewailly E., Nelson C.A., 2011. The effects of maternal binge drinking during pregnancy on neural correlates of response inhibition and memory in childhood. Alcoholism: Clinical and Experimental Research. 35(1), 69-82.


8. Rasmussen C., Becker M., McLennan J., Urichuk L., Andrew G., 2011. An evaluation of social skills in children with and without prenatal alcohol exposure. Child; Care, Health and Development. 37(5), 711-718.


9. Barr H.M., Bookstein F.L., O'Malley K.D., Connor P.D., Huggins J.E., Streissguth A.P., 2006. Binge drinking during pregnancy as a predictor of psychiatric disorders on the Structured Clinical Interview for DSM-IV in young adult offspring. American Journal of Psychiatry. 163(6), 1061-1065.


10. Davis K.M., Wu J.Y. 2001. Role of glutamatergic and GABAergic systems in alcoholism. Journal of Biomedical Science. 8(1), 7-19.


11. Cook R.T., 1998. Alcohol abuse, alcoholism, and damage to the immune system-a review. Alcoholism: Clinical and Experimental Research. 22(9), 1927-1942.


12. Lizardi-Cervera J., Almeda P., Guevara L., Uribe M., 2003. Hepatic encephalopathy: a review. Annals of Hepatology. 2(3), 122-130.


13. Farhadi L., Hojati V., Khaksari M., Vaezi G., 2022. Neuroprotective effects of crocin against ethanol neurotoxicity in the animal model of fetal alcohol spectrum disorders. Neurochemical Research. 47, 1001-1011.


14. Jafari M., Hojati V., Khaksari M., Vaezi G., 2021. Simvastatin attenuates spatial memory impairment via inhibiting microgliosis and apoptotic cell death against ethanol induced neurotoxicity in the developing rat hippocampus. Brain Research.1758, 1-9.


15. Lee Y.J., Kim J.Y., Lee D.Y, Park KJ, Kim G.H., Kim J.E., Roh G.S., Lim J.Y., Koo S., Lim N.K., Park H..Y, Kim W.H., 2020. Alcohol consumption before pregnancy causes detrimental fetal development and maternal metabolic disorders. Scientific Reprorts. 10(1), 10054.


16. Brolese G., Lunardi P., Broetto N., Engelke D.S., Lirio F., Batassini C., Tramontina A.C., Goncalves C., 2014. Moderate prenatal alcohol exposure alters behavior and neuroglial parameters in adolescent rats. Behavioural Brain Research. 269, 175-184.


17. Waltman R., Iniquez E.S., 1972. Placental transfer of ethanol and its elimination at term. Obstetrics and 40(2), 180-185.


18. Brien J.F., Loomis C.W., Tranmer J., McGrath M., 1983. Disposition of ethanol in human maternal venous blood and amniotic fluid. American Journal of Obstetrics and Gynecology. 146(2), 181-186.


19. Climent E., Pascual M., Renau‐Piqueras J., Guerri C., 2002. Ethanol exposure enhances cell death in the developing cerebral cortex: role of brain‐derived neurotrophic factor and its signaling pathways. Journal of Neuroscience Research. 68(2), 213-225.


20. Feng M.J., Yan S.E., Yan Q.S., 2005. Effects of prenatal alcohol exposure on brain-derived neurotrophic factor and its receptor tyrosine kinase B in offspring. Brain Research. 1042(2), 125-132.


21. Boschen K., Klintsova A., 2017. Neurotrophins in the brain: interaction with alcohol exposure during development.  Vitamins and Hormones. 104, 197-242.


22. Heaton M.B., Mitchell J.J., Paiva M., Walker D.W., 2000. Ethanol-induced alterations in the expression of neurotrophic factors in the developing rat central nervous system. Developmental Brain Research. 121(1), 97-107.


23. Stragier E., Massart R., Salery M., Hamon M., Geny D., Martin V., 2015. Ethanol-induced epigenetic regulations at the BDNF gene in C57BL/6J mice. Molecular Psychiatry. 20(3), 405-412.


24. Isari N., Goudarzi I., Lashkarbolouki T., Elahdadi Salmani M., 2022. Effects of maternal ethanol exposure during pregnancy and lactation periods on anxiety- like behaviors and hippocampal brain-derived neurotrophic factor in rat offspring. Kurdistan University of Medical Sciences. 27(1), 1-12.


25. Carlezon W.A., Duman R.S., Nestler E.J., 2005. The many faces of CREB. Trends in Neurosciences. 28(8), 436-445.


26. Wu A., Ying Z., Gomez-Pinilla F., 2004. The interplay between oxidative stress and brain derived neurotrophic factor modulates the outcome of a saturated fat diet on synaptic plasticity and cognition. European Journal of Neuroscience. 19(7), 1699-1707.