Histological and Immunohistochemical Insights into the Neuroprotective Effects of Ibresartan on Lipopolysaccharide-Induced Neuroinflammation

Abstract

Neuroinflammation is a key contributor to the development of various neurological and psychiatric disorders. Irbesartan (IRB), a selective angiotensin receptor blocker, has demonstrated protective properties in multiple organ systems. This study investigates the potential neuroprotective effect of IRB against lipopolysaccharide (LPS)-induced neuroinflammation. Twenty-four male Wistar Albino rats were randomly assigned into three groups: control, LPS-treated (5 mg/kg), and LPS+IRB-treated (IRB 3 mg/kg). All drugs were given intraperitoneally. One hour after the LPS injection, the IRB group received the treatment. Six hours post-LPS administration, animals were sacrificed, and tissues were gathered for hematoxylin-eosin and immunostaining assessments. Caspase-3 and tumor necrosis factor-alpha levels were analyzed. LPS exposure led to notable pathological changes, including vascular congestion, edema, infiltration of neutrophils, micro hemorrhages, and neuronal degeneration in the examined brain regions. Immunohistochemistry revealed a marked elevation in apoptotic and inflammatory marker expression levels in the LPS group. Treatment with IRB significantly reduced both the histopathological damage and the expression of these inflammatory and apoptotic markers. IRB alleviated the detrimental effects of LPS-induced neuroinflammation in the rat brain, supporting its potential as a neuroprotective agent. Further studies are required to determine its efficacy across varying dosages and administration protocols.

Keywords

• Apoptosis
• Angiotensin receptor blocker
• Endotoxin
• Neuroinflammation
• Tissue protection

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