Alzheimer’s disease (AD), the primary cause of dementia accounting for 60% to 70% of cases globally, results in a gradual decline in cognitive abilities, affecting memory, executive function, and daily activities. Recent research highlights the essential involvement of the microbiota-gut-brain axis in AD pathogenesis, characterized by complex bidirectional signaling that modulates neuroinflammation, neurogenesis, neurotransmission, and immune functions. This manuscript extends the discussion beyond the gut alone by emphasizing the significance of the oral-gut microbiota axis as a dynamic and relatively under-investigated factor in AD progression. Microbial populations in both the oral cavity and gastrointestinal tract produce key neurotransmitters, such as gamma-aminobutyric acid, noradrenaline, and dopamine, as well as neuroactive metabolites like short-chain fatty acids, which together impact brain physiology. Disturbances in gut and oral microbial balance can compromise barrier integrity, promoting systemic inflammation and neuroinflammation, and facilitating amyloid-β plaque formation and tau-related changes typical of AD. This review introduces a novel probiotic, prebiotics, synbiotics, and postbiotics (PPSP) therapeutic model designed to modulate both oral and gut microbiota, aiming to restore homeostasis, regulate neuroimmune interactions, and counteract cognitive impairment.We comprehensively assess emerging clinical and translational findings supporting the effectiveness of microbiota-targeted therapies in the scope of this dual-axis framework, addressing both their potential to alter disease course and recognized limitations.By underscoring the importance of the integrated oral-gut microbiota axis alongside targeted PPSP interventions, this manuscript puts forth a paradigm-shifting conceptual strategy that may redefine approaches to AD management and improve cognitive outcomes.

OBJECTIVES: The emergence of resistant bacteria is being increasingly reported around the world, potentially threatening millions of lives. Amongst resistant bacteria, methicillin-resistant Staphylococcus aureus (MRSA) is the most challenging to treat. This is due to emergent MRSA strains and less effective traditional antibiotic therapies to Staphylococcal infections. The use of bacteriophages (phages) against MRSA is a new, potential alternate therapy. In this study, morphology, genetic and protein structure of lytic phages against MRSA have been analysed. METHODS: Isolation of livestock and sewage bacteriophages were performed using 0.4 μm membrane filters. Plaque assays were used to determine phage quantification by double layer agar method. Pure plaques were then amplified for further characterization. Sulfate-polyacrylamide gel electrophoresis and random amplification of polymorphic DNA were run for protein evaluation, and genotyping respectively. Transmission electron microscope was also used to detect the structure and taxonomic classification of phage visually. RESULTS: Head and tail morphology of bacteriophages against MRSA were identified by transmission electron microscopy and assigned to the Siphoviridae family and the Caudovirales order. CONCLUSION: Bacteriophages are the most abundant microorganism on Earth and coexist with the bacterial population. They can destroy bacterial cells successfully and effectively. They cannot enter mammalian cells which saves the eukaryotic cells from lytic phage activity. In conclusion, phage therapy may have many potential applications in microbiology and human medicine with no side effect on eukaryotic cells.
Agar ; Bacteria ; Bacteriophages ; Caudovirales ; Classification ; DNA ; Electrophoresis ; Eukaryotic Cells ; Head ; Humans ; Livestock ; Membranes ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Methods ; Microscopy, Electron, Scanning Transmission ; Microscopy, Electron, Transmission ; Sewage ; Siphoviridae ; Staphylococcal Infections ; Tail