To provide a diagnosis of, in one aspect, physiopathological ageing, in particular premature ageing or accelerated ageing, or a progeroid syndrome, such as Cockayne syndrome (CS), or neurodegenerative disorders or associated symptoms, or to provide a better diagnosis of symptoms of treatment and treatment.SOLUTION: The invention relates to a method for in vitro investigating mitochondrial replication dysfunction in a biological sample removed from a subject susceptible of suffering from physiological ageing or physiopathological conditions related to physiological ageing, or physiopathological ageing or associated symptoms or conditions, in particular premature ageing or accelerated ageing, or of a progeroid syndrome, such as Cockayne syndrome (CS), or neurodegenerative disorders or symptoms thereof, in which levels of at least one species selected in a group of: POLG1 protein, POLG1 RNA, POLG2 protein, protease(s) which have POLG as a target, in particular serine protease(s) such as HTRA3 protein, HTRA2 protein, HTRA3 RNA or HTRA2 RNA, or any combination of these species, are investigated. The invention also relates to kits and uses thereof, a therapeutic method against progeroid-like syndromes or symptoms, and a screening method for identifying particular protease inhibitor(s) and/or nitroso-redox stress scavenger compound(s) having relevance for the symptoms discussed herein.SELECTED DRAWING: None
METHOD FOR IN VITRO INVESTIGATING MITOCHONDRIAL REPLICATION DYSFUNCTION IN BIOLOGICAL SAMPLE, KIT AND USE THEREOF, THERAPEUTIC METHOD AGAINST PROGEROID-LIKE SYNDROME OR SYMPTOMS, AND SCREENING METHOD FOR IDENTIFYING PARTICULAR PROTEASE INHIBITOR(S) AND/OR NITROSO-REDOX STRESS SCAVENGER COMPOUND(S)