Protective Effects of Long-Term Escitalopram Administration on Memory and Hippocampal BDNF and BCL-2 Gene Expressions in Rats Exposed to Predictable and Unpredictable Chronic Mild Stress

• Published in: Brain sciences Vol. 14; no. 5; p. 420
• Main Authors: Saedi Marghmaleki, Vajihe, Radahmadi, Maryam, Alaei, Hojjatallah, Khanahmad, Hossein
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 25.04.2024
• Subjects: Animal cognition; Apoptosis; BCL-2; Bcl-2 protein; BDNF; Brain-derived neurotrophic factor; Citalopram; Drug dosages; Employment; escitalopram; Gene expression; Hippocampus; Latency; Light; Medical research; Memory; Neurogenesis; predictable stress; Serotonin; Stress; unpredictable stress; Iran; BCL-2; escitalopram; predictable stress; unpredictable stress; memory; BDNF
• ISSN: 2076-3425; 2076-3425
• DOI: 10.3390/brainsci14050420

Stress and escitalopram (an anti-stress medication) can affect brain functions and related gene expression. This study investigated the protective effects of long-term escitalopram administration on memory, as well as on hippocampal BDNF and BCL-2 gene expressions in rats exposed to predictable and unpredictable chronic mild stress (PCMS and UCMS, respectively). Male rats were randomly assigned to different groups: control (Co), sham (Sh), predictable and unpredictable stress (PSt and USt, respectively; 2 h/day for 21 consecutive days), escitalopram (Esc; 10 mg/kg for 21 days), and predictable and unpredictable stress with escitalopram (PSt-Esc and USt-Esc, respectively). The passive avoidance test was used to assess behavioral variables. The expressions of the BDNF and BCL-2 genes were assessed using real-time quantitative PCR. Latency significantly decreased in the PSt and USt groups. Additionally, latency showed significant improvement in the PSt-Esc group compared to the PSt group. The expression of the BDNF gene significantly decreased only in the USt group. BDNF gene expression significantly increased in the PSt-Esc and USt-Esc groups compared to their respective stress-related groups, whereas the expression of the BCL-2 gene did not change significantly in both PSt-Esc and USt-Esc groups. PCMS and UCMS had devastating effects on memory. Escitalopram improved memory only under PCMS conditions. PCMS and UCMS exhibited fundamental differences in hippocampal BDNF and BCL-2 gene expressions. Furthermore, escitalopram increased hippocampal BDNF gene expression in the PCMS and UCMS subjects. Hence, neurogenesis occurred more significantly than anti-apoptosis under both PCMS and UCMS conditions with escitalopram.