Inactivation of ERK1/2-CREB Pathway Is Implicated in MK801-induced Cognitive Impairment

Investigating the therapeutic potential of naringin in MK-801-induced schizophrenia model: focus on cognitive impairment and miR-25-3p-regulated pathways

AIM

The aim of this study was to assess the ameliorative effects of naringin (NR) on cognitive impairment in schizophrenia(SZ) from multiple perspectives using behavioral, histopathological and molecular biological approaches.

MATERIALS AND METHODS

SZ models were established in rats via acute intraperitoneal injection of MK-801 in all groups except the control group, which received saline. Cognitive function was assessed using the Morris water maze test 21 days after prophylactic NR administration. Subsequently, Serum interleukin-6 (IL-6) and homocysteine (HCY) levels were quantified using enzyme-linked immunosorbent assay (ELISA), and hippocampal neuronal and synaptic structures were observed via microscopy. Molecular detection was performed using real-time reverse transcription polymerase chain reaction (RT-qPCR) and western blotting (WB) to assess the expression levels of molecules related to the microRNA-25-3p/salt inducible kinase 1/CREB regulated transcription coactivator 2/cAMP responsive element binding protein 1 (miR-25-3p/SIK1/CRTC2/CREB1) pathway, thereby elucidating the mechanism by which NR ameliorates cognitive impairment in SZ.

RESULTS

NR was found to mitigate cognitive decline in learning and memory induced by MK-801. It lowered serum levels of IL-6 and HCY, reduced neuronal damage in the CA1 region of the hippocampus, increased the thickness of postsynaptic dense material, decreased the distance between synaptic gaps, decreased the expression of SIK1, and elevated the expression of miR-25-3p, CRTC2 and CREB1 in the hippocampus.

CONCLUSION

NR may protect neurons in the CA1 region of the hippocampus and enhance synaptic plasticity by regulating the miR-25-3p/SIK1/CRTC2/CREB1 signaling pathway, thereby promoting cognitive improvement.

Progress in The Research of Lactate Metabolism Disruption And Astrocyte-Neuron Lactate Shuttle Impairment in Schizophrenia: A Comprehensive Review

Schizophrenia (SCZ) is a complex neuropsychiatric disorder widely recognized for its impaired bioenergy utilization. The astrocyte-neuron lactate shuttle (ANLS) plays a critical role in brain energy supply. Recent studies have revealed abnormal lactate metabolism in SCZ, which is associated with mitochondrial dysfunction, tissue hypoxia, gastric acid retention, oxidative stress, neuroinflammation, abnormal brain iron metabolism, cerebral white matter hypermetabolic activity, and genetic susceptibility. Furthermore, astrocytes, neurons, and glutamate abnormalities are prevalent in SCZ with abnormal lactate metabolism, which are essential components for maintaining ANLS in the brain. Therefore, an in-depth study of the pathophysiological mechanisms of ANLS in SCZ with abnormal lactate metabolism will contribute to a better understanding of the pathogenesis of SCZ and provide new ideas and approaches for the diagnosis and treatment of SCZ.