GRN and Intervertebral disk degeneration: Progranulin is a 593 amino acid autocrine growth factor that plays a critical role in many pathological and physiological processes, such as inflammation, host defence, wound healing and intervertebral disc degeneration [13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25].