DOI: 10.5061/dryad.c59zw3rfr
title: Data from: Compromised femoral and lumbovertebral bone in the Dp(16)1Yey Down syndrome mouse model

description: Down syndrome (DS), affecting ~1 in 800 live births, is caused by the
 triplication of human chromosome 21 (Hsa21). Individuals with DS have
 skeletal features including craniofacial abnormalities and decreased bone
 mineral density (BMD). Lowered BMD can lead to increased fracture risk,
 with common fracture points at the femoral neck and lumbar spine. While
 the femur has been studied in DS mouse models, there is little research
 done on the vertebrae despite evidence that humans with DS have affected
 vertebrae. Additionally, it is important to establish when skeletal
 deficits occur to find times of potential intervention. The Dp(16)1Yey DS
 mouse model has all genes triplicated on mouse chromosome 16 orthologous
 to Hsa21 and displayed deficits in long bone, including trabecular and
 cortical deficits in male but not female mice, at 12 weeks. We
 hypothesized that the long bone and lumbovertebral microarchitecture would
 exhibit deficits in Dp(16)1Yey mice compared to control mice, long bone
 strength would be diminished in Dp(16)1Yey mice, and  there would
 be a sexual dimorphism in these parameters at 6 weeks. The trabecular
 region of the 4th lumbar (L4) vertebra and the trabecular and cortical
 regions of the femur were analyzed via micro-computed tomography and
 3-point bending in 6-week-old male and female Dp(16)1Yey and littermate
 control mice. Trabecular and cortical deficits were observed in femurs
 from male Dp(16)1Yey mice, and cortical deficits were seen in femurs of
 male and female Dp(16)1Yey mice. Additionally, the L4 of male and female
 Dp(16)1Yey mice show trabecular deficits, which have not been previously
 reported in a DS mouse model. Our results indicate that skeletal deficits
 associated with DS occur early in skeletal development, are dependent on
 skeletal compartment and site, are sex dependent, and potential
 interventions should likely begin early in skeletal development of DS
 mouse models.
description: # Data from: Compromised femoral and lumbovertebral bone in the Dp(16)1Yey
 Down syndrome mouse model The following data was utilized in the following
 manuscript: (citation information) Femoral length and mechanical
 parameters could not be completed for Yey58 and Yey66 due to being broken
 after uCT scanning. Trabecular parameters (BMD, BV/TV, Tb.Th, Tb.Sp, Tb.N)
 were reported for right femurs (Fem.)and 4th lumbar vertebra (Vert.)
 Cortical parameters (Tt.Ar, Ma.Ar, Ct.Ar, Ct.Ar/Tt.Ar, Ct.Th, Ps.Pm,
 Ec.Pm, Ct.TMD) were reported for right femurs. Mechanical parameters
 (remaining) were reported based on 3-point bend for right femurs. Three
 femurs (Yey55,Yey68,Yey77) did not reach a failure point (break), so
 failure points may be overestimated (they are reported for creation of the
 Force-Displacement and Stress-Strain curves). Columns are as follows:
 Sample ID Age of animal at dissection in weeks Sex where M = male and F =
 female Genotype Body weight (Bod.Weight) in grams Femoral length
 (Fem.Length) in millimeters Femoral bone mineral density (Fem.BMD) in
 g/cm^3 Femoral bone volume fraction (Fem.BV/TV) in % Femoral trabecular
 thickness (Fem.Tb.Th) in mm Femoral trabecular separation (Fem.Tb.Sp) in
 mm Femoral trabecular number (Fem.Tb.N) in 1/mm Total cortical
 cross-sectional area (Tt.Ar) in mm^2 Marrow area (Ma.Ar) in mm^2 Cortical
 bone area (Ct.Ar) in mm^2 Cortical area fraction (Ct.Ar/Tt.Ar) in %
 Cortical bone thickness (Ct.Th) in mm Periosteal bone perimeter (Ps.Pm) in
 mm Endocortical bone perimeter (Ec.Pm) in mm Cortical tissue mineral
 density (Ct.TMD) in hydroxyaptite(HA)g/cm^3 Vertebral bone mineral density
 (Vert.BMD) in g/cm^3 Vertebral bone volume fraction (Vert.BV/TV) in %
 Vertebral trabecular thickness (Vert.Tb.Th) in mm Vertebral trabecular
 separation (Vert.Tb.Sp) in mm Vertebral trabecular number (Vert.Tb.N) in
 1/mm Yield force (force at yield point) in N Ultimate force (force at
 ultimate point) in N Failure force (force at failure point) in N
 Displacement to yield [point] in um (micrometers) Ultimate displacement
 (displacement to ultimate point) in um Total displacement (displacement to
 failure point) in um Stiffness (slope of linear section of
 Force-Displacement curve [prior to yield point]) in N/mm Work to yield
 (area under the Force-Displacement curve prior to yield point) in mJ Yield
 stress (stress to yield point) in MPa Ultimate stress (stress to ultimate
 point) in MPa Failure stress (stress to failure point) in MPa Strain to
 yield [point] in ue (microstrain) Ultimate strain (strain to ultimate
 point) in ue Total strain (strain to failure point) in ue Modulus (slope
 of linear section of Stress-Strain curve [prior to yield point]) in GPa
 Resilience (area under the Stress-Strain curve prior to yield point) in
 MPa