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Prenatal MAM Exposure Raises Kynurenic Acid Levels in the Prefrontal Cortex of Adult Rats

Overview
Journal Pharmacol Rep
Specialty Pharmacology
Date 2024 May 24
PMID 38789891
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Abstract

Background: Elevated brain levels of kynurenic acid (KYNA), a metabolite in the kynurenine pathway, are associated with cognitive dysfunctions, which are nowadays often considered as fundamental characteristics of several psychopathologies; however, the role of KYNA in mental illnesses, such as schizophrenia, is not fully elucidated. This study aimed to assess KYNA levels in the prefrontal cortex (PFC) of rats prenatally treated with methylazoxymethanol (MAM) acetate, i.e., a well-validated neurodevelopmental animal model of schizophrenia. The effects of an early pharmacological modulation of the endogenous cannabinoid system were also evaluated.

Methods: Pregnant Sprague-Dawley rats were treated with MAM (22 mg/kg, ip) or its vehicle at gestational day 17. Male offspring were treated with the cannabinoid CB1 receptor antagonist/inverse agonist AM251 (0.5 mg/kg/day, ip) or with the typical antipsychotic haloperidol (0.6 mg/kg/day, ip) from postnatal day (PND) 19 to PND39. The locomotor activity and cognitive performance were assessed in the novel object recognition test and the open field test in adulthood. KYNA levels in the PFC of prenatally MAM-treated rats were also assessed.

Results: A significant cognitive impairment was observed in prenatally MAM-treated rats (p < 0.01), which was associated with enhanced PFC KYNA levels (p < 0.05). The peripubertal AM251, but not haloperidol, treatment ameliorated the cognitive deficit (p < 0.05), by normalizing the PFC KYNA content in MAM rats.

Conclusions: The present findings suggest that the cognitive deficit observed in MAM rats may be related to enhanced PFC KYNA levels which could be, in turn, mediated by the activation of cannabinoid CB1 receptor. These results further support the modulation of brain KYNA levels as a potential therapeutic strategy to ameliorate the cognitive dysfunctions in schizophrenia.

References
1.
Ferraro L, Tomasini M, Beggiato S, Gaetani S, Cassano T, Cuomo V . Short- and long-term consequences of prenatal exposure to the cannabinoid agonist WIN55,212-2 on rat glutamate transmission and cognitive functions. J Neural Transm (Vienna). 2009; 116(8):1017-27. DOI: 10.1007/s00702-009-0230-0. View

2.
Higuera-Matas A, Ucha M, Ambrosio E . Long-term consequences of perinatal and adolescent cannabinoid exposure on neural and psychological processes. Neurosci Biobehav Rev. 2015; 55:119-46. DOI: 10.1016/j.neubiorev.2015.04.020. View

3.
Drazanova E, Ruda-Kucerova J, Kratka L, Stark T, Kuchar M, Maryska M . Different effects of prenatal MAM vs. perinatal THC exposure on regional cerebral blood perfusion detected by Arterial Spin Labelling MRI in rats. Sci Rep. 2019; 9(1):6062. PMC: 6465353. DOI: 10.1038/s41598-019-42532-z. View

4.
Hurd Y, Manzoni O, Pletnikov M, Lee F, Bhattacharyya S, Melis M . Cannabis and the Developing Brain: Insights into Its Long-Lasting Effects. J Neurosci. 2019; 39(42):8250-8258. PMC: 6794936. DOI: 10.1523/JNEUROSCI.1165-19.2019. View

5.
Bara A, Ferland J, Rompala G, Szutorisz H, Hurd Y . Cannabis and synaptic reprogramming of the developing brain. Nat Rev Neurosci. 2021; 22(7):423-438. PMC: 8445589. DOI: 10.1038/s41583-021-00465-5. View