Table 1.
Comparison of literature on uninjured mice subjected to Hypoxia
| Category | Nakada et al. Research Paper | Johnson et al. Research Paper | |
|---|---|---|---|
| Methods | Sex | Males only | Males and Females |
| Hypoxia | Experimental: 7% O2, Tested: 10% O2 | Experimental: 7% O2, Tested: 5% O2 | |
| Analysis | LV and RV analyzed together | LV and RV analyzed separately | |
| Cardiac Morphology | Heart size (HW/BW) | Increased (5 mg/g Normoxia vs. 8 mg/g Hypoxia*) | Increased (4.3 mg/g Normoxia vs. 6.8 mg/g Hypoxia*) |
| CM Cross Sectional Area | Decreased in LV*; Increased in RV* | No change in LV; Increased in RV* | |
| Isolated Cardiomyocyte Size | Not measured | Increased L and SA in LV*; Increased L, W, and SA in RV* | |
| Isolated Myocyte Number | Increased in Ventricles* | No change in LV; No change in RV | |
| CM Nucleation | Increased mononucleated CM* and Decreased binucleated CM* | No change in Nucleation but Increased mononucleated EdU+ isolated CM | |
| Cardiac Myocyte Proliferation | DNA Synthesis-drug given continuously | Increased (0.1% BrdU+ CMs*) | Increased (0.1% EdU+ CMs in LV; 0.1% EdU+ CMs in RV*) |
| DNA Synthesis at Terminal | Not measured | Increased (0.01% Ki67+ CM in LV; 0.02% Ki67+ CM in RV*) | |
| Mitosis at Terminal | Increased (0.06% pH3+ CMs*) | No change (0.002% pH3+ CM in LV; 0% pH3+ CM in RV) | |
| Cytokinesis | Increased (0.0028% Aurora B+ CM*) at Terminal | Increased (MADM mice showed 0.1-0.3% GFP/RFP+ CM in LV and RV*); tamoxifen given during 2 weeks at 7% Oxygen | |
| Cardiac Remodeling | Angiogenesis | No change in Capillary Density; Increased Capillary size* | Increased Capillary density in RV; Increased Capillary Size in LV and RV |
| Fibrosis | Not measured in uninjured mice | Increased in Ventricles* | |
| Apoptosis | Not measured in uninjured mice | Increased in LV*; No change in RV | |
| Cell Proliferation | Global Proliferation of cardiac cells | Not measured | Increased in LV* and RV* (shown as EdU+, Ki67+, and pH3+ cells) |
| Endothelial Cells | Images shown but no Quantification | Increased EdU+ endothelial cells in LV and RV | |
| RNA Sequencing Analysis | Mitochondrial Metabolism | Decreased in LV | Decreased in both ventricles |
| Cell Cycle Regulation | Increased in LV | Increased in both ventricles; Dysregulated G1 to S phase transition | |
| Angiogenesis | Increased in LV | Increased in both ventricles |
Numbers above reflect the estimated averages seen from figures in each paper.
(*)
represents significantly different between normoxia and hypoxia mice. CM, cardiomyocytes; L, length; W, width; SA, surface area.