Assess reversibility of HGPS upon systemic progerin suppression in progeroid mice

WORK PACKAGES 3
WP3Assess reversibility of HGPS upon systemic progerin suppression in progeroid mice Objective: Assess whether HGPS progression can be prevented or delayed by ubiquitously suppressing progerin expression early in life, and how late in HGPS lifespan can progerin be suppressed to still achieve therapeutic benefit. Participants:

All partners
Leader: Vicente Andrés
(P1, SPAIN)
Deliverable: Determination of the degree of reversibility of progerin-induced-damage at different times in the lifespan of LmnaHGPSrev mice.

Mouse model: LmnaHGPSrev/HGPSrev-Ubc-CreER(T2)tg/+ mice are generated by breeding progeroid LmnaHGPSrev mice with Ubc-CreER(T2)tg/+ mice expressing Cre-recombinase ubiquitously upon tamoxifen induction. Progeroid LmnaHGPSrev mice, recently generated by P1, is engineered with loxP sequences to allow inducible suppression of progerin expression by Cre-recombinase activity.

TASK 3.1: Assess reversibility of HGPS phenotype upon suppression of progerin expression ubiquitously early in life when symptoms are barely detectable. Progerin suppression will be achieved by intraperitoneal tamoxifen injection. The follow-up of mice will include:
1) Body weight measurements;
2) Blood extraction for hematology and biochemistry;
3) Western blot and qPCR to quantify lamin A/C and progerin lelves in tissue biopsies and blood cells;
4) Hematoxylin & Eosin staining and -galactoside activity in tissue biopsies to assess morphology and cell senescence;
5) Magnetic Resonance Imaging for accurate anatomical and functional evaluation of the ventricles and quantification of muscle and fat mass ratios;
6) Positron Emission Tomography/Computer Tomography (PET/CT) to obtain information on myocardial glucose metabolism and calcium in atherosclerotic plaques and aortic valves;
7) Echocardiography to assess heart function;
8) Electrocardiography (activities 1 to 8 will be performed by P1 and P2);
9) X-ray and CT-Scan to analyse bone dysplasia focusing on mandible deformity, tooth malocclusion, cranial suture incomplete closure, osteoporosis, kyphosis (by P5);
10) Skin and adipose tissue analysis, focusing on thickness of the epidermis, hair follicle morphology and quality of the connective tissue (by P4);
11) Motor function by grip test and openfield test (by P5);
12) Progerin-expressing and progerin-suppressed skin primary cells will be analysed byP3, P4 and P5 as in WP1 and WP2.

TASK 3.2: Assess reversibility of HGPS phenotype at advanced stages of the disease (body weight loss around 15%). Follow-up of mice will be as described in Task 3.1.

Expected Results:

Assess if HGPS progression can be reverted by suppressing progrerin once an overt phenotype is already present, or, conversely, if progerin expression should be suppressed very early in life to avoid irreversible damage. This information will help define the optimal time of intervention for future curative therapies based on preventing progerin expression.

TREAT-HGPS

Exploring new therapeutic strategies in Hutchinson-Gilford progeria syndrome preclinical models