mortality/aging
• fourth to sixth generation (G4-G6) mutants have shorter median survival times than Terc homozygotes (24 weeks vs. 78 weeks)
• however, first and second generation (G1-G2) mutants have normal appearance, weight gain and lifespan
|
• 12- to 16-week old fourth to sixth generation (G4-G6) mutants have clinical features of premature aging
|
growth/size/body
• fourth to sixth generation (G4-G6) mutants have lower body weights, with a 20% reduction at 4 weeks of age and a 30% reduction at 32 weeks of age
|
cellular
• MEFs from G5 mutants exhibit an increase in chromosomal structural aberrations
• bone marrow metaphases derived from prematurely aged G4-G6 mutants show marked genomic instability, manifesting as more chromosomal p-p, p-q, and q-q arm fusions, and nonreciprocal translocations
|
• prematurely aged G4-G6 mutants exhibit accelerated loss of telomere length in primary bone marrow
|
homeostasis/metabolism
hyperglycemia
(
J:91715
)
• 10 of 12 prematurely aged 20-week old G4-G6 mutants develop type II diabetes based on elevated fasting blood glucose levels, abnormal glucose tolerance tests and increased endogenous insulin levels
|
• prematurely aged 20-week old G4-G6 mutants show incresed endogenous insulin levels
|
• prematurely aged 20-week old G4-G6 mutants show abnormal glucose tolerance tests
|
• 24-week old prematurely aged fifth generation mutants show delayed wound closure
|
• 24-week old prematurely aged fifth generation mutants show impaired healing of acute wounds, with delayed wound closure and fewer proliferating cells at the sites of wound re-epithelialization
|
skeleton
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have femoral bones with decreased cortical thickness and trabecular mass
|
• G1-G3 mutants routinely succumb to osteosarcomas and soft tissue sarcomas at around 63 weeks of age
|
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have hunched spines
|
• increase in bone marrow fat content in young and aged mice
|
• 47.6% and 69.8% decrease in femur bone volume at 3 months of age and in aged mice, respectively
|
• 19% and 60.1% increase in cortical porosity in young and aged mice, respectively
|
• cortical bone area decreases with age, with a 29.7% decrease in aged mice
|
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have femoral bones with decreased cortical thickness
(J:91715)
• decrease in cortical thickness in both young and aged mice
(J:213181)
|
• young femurs show a more rod-like trabecular structure
|
• increase in trabecular separation
|
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have femoral bones with decreased trabecular mass
|
• decrease in trabecular thickness that begins in young age and progresses with age
|
• a proportion of G4-G6 mutants develop early-onset osteoporosis
(J:91715)
• accelerated bone aging with characteristic features of human senile osteoporosis
(J:213181)
|
• osteoid significantly decreases with age
|
• bone shows mechanical alterations including an increase in structure model index, a decrease in anisotropy and a decrease in the moment of inertia
|
• mineralized surface, mineral apposition rate, and bone formation rate dramatically decline with age
|
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have bone fractures
|
vision/eye
reproductive system
small gonad
(
J:91715
)
• 12- to 16-week old G4-G6 mutants show severe hypogonadism
|
small testis
(
J:91715
)
• 20-week old G4-G6 mutants have small testes
|
neoplasm
• although prematurely aged G4-G6 mutants are not prominently cancer-prone (as they die prematurely), G1-G3 mutants routinely succumb to osteosarcomas and soft tissue sarcomas at around 63 weeks of age
|
• G1-G3 mutants routinely succumb to osteosarcomas and soft tissue sarcomas at around 63 weeks of age
|
digestive/alimentary system
• late-generation mutants have an increase in intestinal crypt cell apoptosis compared to Terc homozygotes
|
endocrine/exocrine glands
• late-generation mutants have an increase in intestinal crypt cell apoptosis compared to Terc homozygotes
|
small testis
(
J:91715
)
• 20-week old G4-G6 mutants have small testes
|
limbs/digits/tail
• by 32 weeks of age, all G4-G6 mutants showing signs of premature aging have femoral bones with decreased cortical thickness and trabecular mass
|
adipose tissue
• G4-G6 mutants exhibit a 43% reduction in subcutaneous adipose tissue at 4 months of age
|
• increase in bone marrow fat content in young and aged mice
|
integument
• G4-G6 mutants exhibit a 43% reduction in subcutaneous adipose tissue at 4 months of age
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
osteoporosis | DOID:11476 |
OMIM:166710 |
J:213181 | |
Werner syndrome | DOID:5688 |
OMIM:277700 |
J:91715 |