The JAK1/2 inhibitor ruxolitinib delays premature aging phenotypes

Area of Science:

• Cellular and Molecular Biology
• Genetics and Disease
• Pharmacology

Background:

• Hutchinson-Gilford progeria syndrome (HGPS) stems from an LMNA mutation producing toxic progerin protein.
• Progerin causes premature aging phenotypes and reduced lifespan in affected children.
• Previous research indicated PLA2R1 targeting can mitigate progeria phenotypes by modulating JAK/STAT signaling.

Purpose of the Study:

• To investigate whether direct targeting of the JAK/STAT pathway influences cellular and in vivo progeria phenotypes.
• To evaluate the efficacy of JAK1/2 inhibition using ruxolitinib in a progeria model.

Main Methods:

• Utilized human normal fibroblasts expressing progerin to assess ruxolitinib's effects on cellular senescence and nuclear morphology.
• Administered ruxolitinib to a mouse model of progeria to evaluate its impact on premature aging phenotypes.
• Monitored cellular phenotypes including cell cycle arrest and senescence.
• Assessed in vivo phenotypes such as bone health, grip strength, and survival rates.

Main Results:

• Ruxolitinib effectively rescued progerin-induced cell cycle arrest, cellular senescence, and misshapen nuclei in human fibroblasts.
• In the mouse model, ruxolitinib treatment reduced bone fractures and improved bone mineral content and grip strength.
• A trend towards increased survival was observed in ruxolitinib-treated progeria mice.

Conclusions:

• JAK1/2 inhibition with ruxolitinib demonstrates significant therapeutic potential for HGPS.
• Ruxolitinib ameliorates key cellular and organismal aging phenotypes associated with progeria.
• Further evaluation of ruxolitinib as an HGPS therapeutic is warranted, given its FDA approval status.