Metformin decreases progerin expression and alleviates pathological defects of Hutchinson–Gilford progeria syndrome cells

Abstract

Hutchinson–Gilford progeria syndrome (HGPS) is a rare genetic disorder that causes systemic accelerated aging in children. This syndrome is due to a mutation in the LMNA gene that leads to the production of a truncated and toxic form of lamin A called progerin. Because the balance between the A-type lamins is controlled by the RNA-binding protein SRSF1, we have hypothesized that its inhibition may have therapeutic effects for HGPS. For this purpose, we evaluated the antidiabetic drug metformin and demonstrated that 48 h treatment with 5 mmol/l metformin decreases SRSF1 and progerin expression in mesenchymal stem cells derived from HGPS induced pluripotent stem cells (HGPS MSCs). The effect of metformin on progerin was then confirmed in several in vitro models of HGPS, i.e., human primary HGPS fibroblasts, LmnaG609G/G609G mouse fibroblasts and healthy MSCs previously treated with a PMO (phosphorodiamidate morpholino oligonucleotide) that induces progerin. This was accompanied by an improvement in two in vitro phenotypes associated with the disease: nuclear shape abnormalities and premature osteoblastic differentiation of HGPS MSCs. Overall, these results suggest a novel approach towards therapeutics for HGPS that can be added to the currently assayed treatments that target other molecular defects associated with the disease. A diabetes drug with a proven track record in the clinic may also offer an alternative treatment for a rare ''premature aging'' disorder. A genetic mutation in patients with Hutchinson-Gilford progeria syndrome (HGPS) produces a defective protein called progerin, which causes children to develop skeletal, cardiovascular and other symptoms normally seen in the elderly. Researchers led by Xavier Nissan at I-Stem in France have demonstrated that metformin triggers a biochemical ''switch'' that causes cells to decrease their production of progerin, and instead generate an alternative, non-toxic protein. Relative to untreated cells, metformin-treated cells were less prone to develop structural abnormalities or undergo premature maturation. Importantly, doctors have used metformin for over 20 years, suggesting that such a treatment approach should be safe for HGPS patients.