Прямые и косвенные методы изучения микробиоты человека

Цель публикации: рассмотреть основные методы исследования микробиоты желудочно-кишечного тракта.

Основные положения. В настоящее время молекулярно-генетические методы используются преимущественно для фундаментальных исследований и не имеют единого «протокола» анализа данных, что затрудняет их внедрение в клиническую практику. Исследование короткоцепочечных жирных кислот (КЦЖК) в плазме крови может служить косвенным маркером микробного состава толстой кишки, однако на сегодня нельзя с уверенностью связать количество и соотношение определяемых КЦЖК с определенной нозологической формой; изучение уровня ТМАО в плазме крови и моче также может отражать наличие в составе кишечной микробиоты особых кластеров бактерий, несущих гены Cut, CntA/CntB и YeaW/YeaX. Однако необходимы дальнейшие исследования по выявлению корреляционных связей между определенными заболеваниями, микробным составом ЖКТ, рационом и уровнем ТМАО. Газовые биомаркеры (водород, метан и сероводород) гораздо лучше изучены по сравнению с другими типами биомаркеров функции и состава микробиоты. Преимуществом газовых биомаркеров является возможность их неинвазивного, многократного измерения, что позволяет получать информацию о соотношении гидрогенных и гидрогенотрофных микроорганизмов.

Выводы. Объединение информации, полученной при исследованиях кишечной микробиоты на уровнях генома, транскриптома и метаболома, позволит произвести более глубокий анализ состава и функционирования микробиоты человека. Такой подход имеет несомненный потенциал для понимания патогенеза различных заболеваний и открывает возможности для разработки новых стратегий профилактики и лечения. 

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