INS and hyperinsulinism: An increase in FSH was accompanied by a decrease in follistatin and an increase in activin A.29An in vitro study discovered that activin A played anti‐inflammatory and antioxidant roles in endothelial cells and insulin sensitization and anti‐inflammatory roles in human islet cells, which demonstrated that activin A could prevent hyperglycemia, hyperinsulinemia, and inflammation.28, 30