Prof. Chrousos has been at the forefront of stress research for more than 40 years and he is internationally recognized for his research on the glucocorticoid signaling system of the cell, on the diseases of the HPA axis, and on the physiologic, pathophysiologic and molecular mechanisms of stress and stress-related disorders.
Prof. Chrousos’ research program has focused on stress and glucocorticoid physiology. Adaptations to stressful changes in exogenous/endogenous states and conditions represent perhaps the most central feature of life. Glucocorticoids, the end-hormones of the hypothalamic-pituitary-adrenal (HPA) axis, are central to this process, given their key roles in behavioral and physical/energetic adaptations, acting on more elements of the genome than any other biological ligand, while they also affect the epigenome and regulate mitochondrial function. Prof. Chrousos is internationally recognized for his research on the glucocorticoid signaling system of the cell, on the diseases of the HPA axis, and on the physiologic, pathophysiologic and molecular mechanisms of stress and stress-related disorders. Prof. Chrousos described the syndrome of glucocorticoid resistance that carries his name (Chrousos syndrome) as a disease of the glucocorticoid receptor and subsequently reported the majority of the kindreds with this disorder in the world.
He started his research with the molecular elucidation, diagnosis and treatment of the primary glucocorticoid resistance syndrome in man and described the “pan-steroid” resistance of nonhuman New World primates. He continued with extensive basic work on the glucocorticoid signaling system and its involvement in cellular function, physiology and pathophysiology. He proceeded further with studying and expounding the regulation of the key hypothalamic neuropeptide CRH and its involvement in major functions of the organism, such as dealing with stress or immune challenges, regulating behavior, affect, appetite and sleep. He associated excessive or deficient CRH secretion with disease. Prof. Chrousos demonstrated that CRH is secreted peripherally (“immune CRH”) and participates directly in the inflammatory reaction as a potent degranulator of mast cells, mediating stress-triggered states such as asthma and migraine headaches. He demonstrated sexual dimorphism in the CRH and stress system response, with female predominance, and developed a clinically useful CRH test employed in the differential diagnosis of Cushing syndrome and pseudo-Cushing states and adrenal insufficiency. He employed this test as a research tool in the study of complex human disorders.
He delineated the key pathophysiology of a number of human states characterized by high or low CRH secretion, such as, respectively, melancholic depression, anorexia nervosa, idiopathic insomnia and obligate athleticism or atypical and seasonal depression, postpartum blues/depression and the chronic fatigue and fibromyalgia syndromes. He extended this work to other common human states, such as obesity/metabolic syndrome, sleep disorders, autoimmune diseases and the post-traumatic stress disorder. He synthesized seemingly disparate mechanisms and disorders into a logical heuristic model that has been accepted and referred to by thousands of investigators..
Prof. Chrousos has performed biomedical research from the basic molecular/ cellular level all the way to the diagnosis, treatment and management of disease and then to public health. His work has opened new horizons in our understanding of a spectrum of human complex disorders, including melancholic, atypical and postpartum depression, the eating disorders, the metabolic syndrome, the psychosomatic and sleep disorders, and inflammatory autoimmune and allergic diseases. His contributions span a range of medical disciplines, including Pediatrics, Reproductive Medicine, Internal Medicine, Endocrinology, Psychiatry and Psychology, Epidemiology, Rheumatology/ Immunology, Allergy, Sleep Medicine, Psychosomatic Medicine, Surgery and Oncology.