Zależność między składem mikrobioty jelitowej a patogenezą choroby Alzheimera

The pathology associated with dementia is compounded by a number of associated condi-tions. These include inappropriate eating habits leading to the development of obesity and asso-ciated conditions of hyperglycaemia, hypercholesterolaemia and hypertension. Advanced age,inadequate nutritional status including excessive body weight, but also malnutrition with coex-isting metabolic abnormalities are fundamental factors predisposing to an abnormal proportionof microbes inhabiting the human gastrointestinal tract.Significant differences have been demonstrated in the composition of the gut microbiota ofpeople with Alzheimer’s disease compared to those without cognitive impairment. These differ-ences include conversion of microorganisms, towards species that promote inflammatory proc-esses and activate the amyloid cascade. These primarily include Escherichia coli, Salmonella typhimurium, Pseudomonas fluoroscens, Staphylococcus aureus, Bacillus subtilis, Salmonella enterica, Mycobacterium tuberculosis. Chronic inflammation within the intestines can correlatewith neuroinflammatory processes. This is due to the fact that a two-way communication isobserved between these centres, which involves the interaction of the intestinal microbiota viachemical and hormonal signals.The condition of intestinal dysbiosis disrupts the integrity of the gut-brain axis, which mani-fests itself in the unrestricted distribution of substances that show negative effects on centralnervous system functions via the blood-brain barrier. These are primarily lipopolysaccharideand trimethylamine oxide. These substances may correlate with a number of dysfunctions thatappear to exacerbate inflammatory responses and thus trigger the pathomechanistic pathway ofdementia.The most important determinant that can effectively alter the composition of the microbiota isadherence to a balanced diet rich in dietary fibre, omega-3 polyunsaturated fatty acids and phe-nolic compounds. Adherence to a Mediterranean diet significantly delays processes associatedwith neurodegeneration and promotes the diversity of the probiotic microbiota.