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Imipramine reverses depressive-like parameters in pneumococcal meningitis survivor rats
Tatiana Barichello1, Graziele Milioli, Jaqueline S Generoso
1Laboratório de Microbiologia Experimental e Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, 88806-000 Criciúma, SC, Brazil. tba@unesc.net
Abstract:
Pneumococcal meningitis is a severe infectious disease of the central nervous system, associated with acute inflammation and might cause damage to the host, such as deafness, blindness, seizure, and learning deficits. However, infectious diseases can play a significant role in the etiology of neuropsychiatric disturbances. In this context, we evaluated depressive-like parameters; corticosterone and ACTH levels in pneumococcal meningitis surviving rats. Wistar rats underwent a magna cistern tap receiving either 10 μL sterile saline or a Streptococcus pneumoniae suspension at the concentration of 5 × 10(9) cfu/mL. After 3 days of meningitis induction procedure, the animals were treated with imipramine at 10 mg/kg or saline for 14 days (3rd-17th day). The consumption of sweet food was measured for 7 days (10th-17th day). The meningitis group decreased the sucrose intake and increased the levels of corticosterone and ACTH levels in the serum and TNF-α in the cortex; however, the treatment with imipramine reverted the reduction of sweet food consumption, normalized hormonal levels and TNF-α in the cortex. Our results supported the hypothesis that the pneumococcal meningitis surviving rats showed depressive-like behavior and alterations in the hypothalamus-pituitary-adrenal axis.
Insights
Pneumococcal meningitis survivors exhibit depressive-like behaviors and hormonal imbalances. The antidepressant imipramine effectively reversed these effects in rats, suggesting a link between meningitis and neuropsychiatric disturbances.
Area of Science:
- Neuroscience
- Infectious Diseases
- Psychiatry
Background:
- Pneumococcal meningitis is a severe central nervous system infection causing inflammation and potential long-term damage.
- Infectious diseases, including meningitis, are implicated in the development of neuropsychiatric disorders.
Purpose of the Study:
- To investigate depressive-like behaviors and hypothalamic-pituitary-adrenal (HPA) axis alterations in rats surviving pneumococcal meningitis.
- To evaluate the therapeutic potential of imipramine in mitigating these post-meningitis effects.
Main Methods:
- Wistar rats were induced with pneumococcal meningitis or saline control via magna cistern tap.
- Animals received imipramine or saline treatment for 14 days post-induction.
- Depressive-like behavior (sucrose intake), serum corticosterone, ACTH, and cortical TNF-α levels were assessed.
Main Results:
- Meningitis survivors showed reduced sucrose intake, elevated corticosterone and ACTH, and increased cortical TNF-α.
- Imipramine treatment normalized sucrose intake, hormonal levels, and TNF-α in meningitis survivors.
- These findings indicate meningitis-induced depressive-like behavior and HPA axis dysregulation.
Conclusions:
- Pneumococcal meningitis survivors exhibit significant depressive-like behaviors and HPA axis disturbances.
- Imipramine demonstrates efficacy in reversing these neurological and hormonal alterations.
- This study supports the role of infectious diseases in neuropsychiatric conditions and highlights potential therapeutic targets.
