In the recent years, the accelerating global demographic shift toward population aging has been accompanied by a marked increase in the prevalence of neurodegenerative disorders, notably Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and multiple sclerosis. Among emerging approaches, dietary interventions targeting the gut–brain axis have garnered considerable attention, owing to their potential to modulate key pathogenic pathways underlying neurodegenerative processes. This review synthesizes current concepts in precision nutrition and elucidates neurohumoral, immune, and metabolic regulatory mechanisms mediated by the gut microbiota, including the roles of the vagus nerve, cytokines, short-chain fatty acids, vitamins, polyphenols, and microbial metabolites. Emerging evidence underscores that dysbiotic alterations contribute to compromised barrier integrity, the initiation and perpetuation of neuroinflammatory responses, pathological protein aggregations, and the progressive course of neurodegenerative diseases. Collectively, these insights highlight the gut microbiota as a pivotal target for the development of precision-based dietary strategies in the prevention and mitigation of neurodegenerative disorders. Particular attention is devoted to key bioactive components such as prebiotics, probiotics, psychobiotics, dietary fiber, omega-3 fatty acids, and polyphenols that critically participate in regulating the gut–brain axis. Contemporary evidence on the contribution of the gut microbiota to the pathogenesis of Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis is systematically summarized. The review further discusses the prospects of applying nutrigenomics, chrononutrition, and metagenomic analysis to the development of personalized dietary strategies. The presented findings underscore the potential of integrating precision nutrition with targeted modulation of the gut–brain axis as a multifaceted approach to reducing the risk of neurodegenerative diseases and preserving cognitive health.

Актуальность. Статья содержит аналитические данные и теоретические расчеты о распространенности в Казахстане деменций, по разным факторам возникновения, на основе полученной статистики от МЗ РК. Проведен сравнительный анализ распространенности деменций в Казахстане и в мире. На сегодня количество пациентов в стране составляет около 10 000 человек, что в 14 раз меньше предварительного расчетного количества, антидементную терапию получают лишь 10% зарегистрированных больных. Проблема деменций является гораздо более широкой, но на данный момент геронтологическая служба страны игнорирует данную проблему. Указаны основные понятия и термины для диагностики, наблюдения и лечения деменций. Дано различие понятий «деменция» и «болезнь Альцгеймера». Перечислены основные законодательные акты, на основе которых можно диагностировать деменции и болезнь Альцгеймера с указанием лекарственного обеспечения, льгот. Предлагается дальнейшее изменение законодательства для улучшения выявления когнитивного снижения. Цель: теоретическое прогнозирование деменций и демонстрация актуальности темы когнитивного снижения медицинскому сообществу Республики Казахстан, анализ литературных источников по распространенности и факторам риска деменций. Стратегия поиска: Поиск источников проводили в следующих базах: Reports& resources of Alzheimer's Disease International, Nature Portfolio Collections, EClinicalMedicine, The Lancet Public Health, CyberLeninka, PubMed, Medscape и имеющаяся печатная литература. Глубина поиска составила 10 лет: с 2011 по 2021 годы. Критериями включения являлись: мета-анализы и систематические обзоры; статьи на английском и русском языках, популяционные когортные исследования по теме деменций. Исключались публикации низкого методологического качества, повторяющиеся публикации, клинические случаи. Поиск осуществлялся ручным способом по ключевым словам: деменция, болезнь Альцгеймера. Всего проанализировано 115 публикаций, из них 74 включены в данную работу. Работа инициативная, выполнена с целью привлечения внимания медицинской общественности к проблеме деменций. Результаты: Обзор литературы показал, что за последние десятилетия распространенность деменций растет и к 2050 году составит 132 млн человек по всему миру. Прогнозируемая распространенность деменций в Казахстане может оказаться около 150 000 человек. Выводы:распространенность деменций в Казахстане является актуальной и требующей дальнейшего выявления пациентов, изучения проблемы, создания эффективной законодательной базы и социальной защиты. Relevance:The article contains analytical data and theoretical calculations on the prevalence of dementia in Kazakhstan by various factors of occurrence, based on statistics obtained from the Kazakhstans Ministry of Health. A comparative analysis of the prevalence of dementia in Kazakhstan and in the world has been carried out. At present, the number of patients in the country is about 10,000, which is 14 times less than the preliminary estimated number; only 10% of registered patients receive antidemently therapy. The problem of dementia is much broader, but at the moment the country's gerontological service ignores this problem. The basic concepts and terms for the diagnosis, monitoring and treatment of dementia are indicated. The difference between the concepts of "dementia" and "Alzheimer's disease" is given. The main legislative acts are listed, but on the basis of which it is possible to diagnose dementia and Alzheimer's disease with an indication of drug provision, benefits. Further legislative changes are proposed to improve the detection of cognitive decline. Objective: to demonstrate the relevance of the topic of cognitive decline to the medical community, review the literature on the prevalence and risk factors of dementia. Search strategy: The search for sources was carried out in the following databases: Reports & resources of Alzheimer's Disease International , Nature Portfolio Collections, EClinicalMedicine, The Lancet...

The gut microbiome has been proposed as a contributor to Alzheimer’s disease (AD) pathogenesis via the microbiota–gut–brain axis, but findings across cohorts are inconsistent and scarce data exist from Central Asian populations. We used shotgun metagenomic sequencing to compare the gut microbiome of AD patients and cognitively healthy controls from Kazakhstan. In a cross-sectional case–control study (35 AD, 39 Control), we profiled taxonomic and functional (HUMAnN pathway) composition, and compared alpha/beta diversity, individual taxa and pathways, and their association with clinical and demographic variables (Mann–Whitney U test, PERMANOVA/PERMDISP, OLS regression, all BH-FDR corrected, sensitivity analysis using ANCOM-BC2), with sensitivity analyses adjusting for age and BMI and applying Bonferroni correction. Within the AD group, circulating adiponectin—measured only in this group—was examined for associations with microbiome features in an exploratory analysis. Alpha diversity was lower in AD (q < 0.05). Community composition also separated by group on PERMANOVA (R² = 8.6%, p = 0.001), and this separation held after adjusting for age and BMI. A total of 178 taxa differed significantly between groups (BH-FDR; 37 were also Bonferroni-significant), most prominently depletion of Faecalibacterium and enrichment of Eisenbergiella and Desulfovibrio in AD; 100 pathways differed significantly (20 Bonferroni-significant). Three clinical/demographic variables (total bilirubin, atherogenic index, BMI) were associated with specific taxa or pathways. Within the AD group, adiponectin correlated negatively with the pathway assimilatory sulfate reduction IV (rho = −0.60, q = 0.015). AD in this Central Asian cohort was associated with a less diverse, compositionally distinct gut microbiome, with depletion of butyrate-producing Firmicutes and enrichment of sulfate-reducing taxa, alongside other taxa whose direction of association differed from prior reports.