Bridging gap in the treatment of Alzheimer's disease via postbiotics: Current practices and future prospects

Aging is an extremely significant risk associated with neurodegeneration. The most prevalent neurodegenerative disorders (NDs), such as Alzheimer's disease (AD) are distinguished by the prevalence of proteinopathy, aberrant glial cell activation, oxidative stress, neuroinflammation, defective autophagy, cellular senescence, mitochondrial dysfunction, epigenetic changes, neurogenesis suppression, increased blood-brain barrier permeability, and intestinal dysbiosis that is excessive for the patient's age. Substantial body studies have documented a close relationship between gut microbiota and AD, and restoring a healthy gut microbiota may reduce or even ameliorate AD symptoms and progression. Thus, control of the microbiota in the gut has become an innovative model for clinical management of AD, and rising emphasis is focused on finding new techniques for preventing and/or managing the disease. The etiopathogenesis of gut microbiota in driving AD progression and supplementing postbiotics as a preventive and therapeutic treatment for AD is discussed. The review additionally discusses the use of postbiotics in AD prophylaxis and therapy, portraying them as substances that address senescence-triggered dysfunctions and are worthy of translating from bench to biopharmaceutical market in response to "silver consumers" needs. The current review examines and evaluates the impact of postbiotics as whole and specific metabolites, such as short-chain fatty acids (SCFAs), lactate, polyamines, polyphenols, tryptophan metabolites, exopolysaccharides, and bacterial extracellular vesicles, on the aging-associated processes that reinforce AD. Moreover, it provides an overview of the most recent data from both clinical and preclinical research involving the use of postbiotics in AD.