Synthesis and Neurobehavioral Evaluation of a Potent Multitargeted Inhibitor for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) poses a significant health challenge worldwide, affecting millions of individuals, and projected to increase further as the global population ages. Current pharmacological interventions primarily target acetylcholine deficiency and amyloid plaque formation, but offer limited efficacy and are often associated with adverse effects. Given the multifactorial nature of AD, there is a critical need for novel therapeutic approaches that simultaneously target multiple pathological pathways. Targeting key enzymes involved in AD pathophysiology, such as acetylcholinesterase, butyrylcholinesterase, beta-site APP cleaving enzyme 1 (BACE1), and gamma-secretase, is a potential strategy to mitigate disease progression. To this end, our research group has conducted comprehensive in silico screening to identify some lead compounds, including IQ6 (SSZ), capable of simultaneously inhibiting the enzymes mentioned above. Building upon this foundation, we synthesized SSZ, a novel multitargeted ligand/inhibitor to address various pathological mechanisms underlying AD. Chemically, SSZ exhibits pharmacological properties conducive to AD treatment, featuring pyrrolopyridine and N-cyclohexyl groups. Preclinical experimental evaluation of SSZ in AD rat model showed promising results, with notable improvements in behavioral and cognitive parameters. Specifically, SSZ treatment enhanced locomotor activity, ameliorated gait abnormalities, and improved cognitive function compared to untreated AD rats. Furthermore, brain morphological analysis demonstrated the neuroprotective effects of SSZ, attenuating A beta-induced neuronal damage and preserving brain morphology. Combined treatment of SSZ and conventional drugs (DON and MEM) showed synergistic effects, suggesting a potential therapeutic strategy for AD management. Overall, our study highlights the efficacy of multitargeted ligands like SSZ in combating AD by addressing the complex etiology of the disease. Further research is needed to elucidate the full therapeutic potential of SSZ and the exploration of similar compounds in clinical settings, offering hope for an effective AD treatment in the future.