IL21 and hypertensive disorder: They are characterized by the secretion of IL-9, as well as IL-10 and IL-21, and are described to play a proinflammatory role in allergic reactions; however, they also exert protection against parasitic helminth infections and are endowed with robust anticancer capacity.52 Yet, the link between Th9 and hypertension remains undiscovered.46 Similarly, this is the first report disclosing an induction of Th9 upon butyrate intake.