Baicalein's neuroprotective effects in a lansoprazole-induced Alzheimer's model in Wistar rats

Abstract

Introduction and aim. Alzheimer's disease (AD) is a devastating neurodegenerative disorder and the most frequently diagnosed type of dementia. Baicalein, a flavonoid found in the roots of Scutellaria baicalensis, was useful in preventing neuronal injury in various neurodegenerative models. The present study was designed to determine the neuroprotective effect of baicalein in lansoprazole-induced AD in Wistar rats. Material and methods. We used male Wistar rats randomly divided into six groups: control, vehicle, lansoprazole-induced, and baicalein+lansoprazole or baicalein treated. The lowest dose, lansoprazole (30 mg/kg), was administered orally for 28 weeks to induce AD-like pathology. Baicalein (10 mg/kg) was coadministered with lansoprazole in the treatment group. Cognitive functions were evaluated using a Morris water maze (MWM) and a novel object recognition test. Acetylcholinesterase (AChE) activity, determination of oxidative stress, including malondialdehyde, superoxide dismutas, and reduced glutathione levels, and inflammation-related cytokines such as tumor necrosis factor α were biochemically analyzed. We collected hippocampal sections to assess amyloid beta deposition and neuronal integrity histochemically. Results. Lansoprazole-induced rats showed marked cognitive decline accompanied by enhanced AChE activity, increased oxidative stress, and levels of pro-inflammatory cytokines compared to controls (p<0.01). Co-administration of Baicalein significantly improved cognitive performance, AChE activity was reduced to control levels, oxidative stress markers decreased to near-normal values in the brain and blood, and inflammatory cytokines were significantly lower compared to rats treated with the lansoprazole-treated rats (p<0.01). Baicalein treatment attenuated plaque deposition and neuronal injury, as revealed by histopathological analysis in vivo. Conclusion. Baicalein has a protective effect on lansoprazole-induced AD in Wistar rats. These appear to be due to the flavonoid's antioxidative, anti-inflammatory, and enzyme-inhibiting activities on AChE. These results propose baicalein as a potential therapeutic agent for further study with respect to prevention and treatment, especially in patients under long-term administration of proton pump inhibitors.