Table 4. Bone (femur) gene expression (mRNA) as measured by quantitative RT/PCR (qRT-PCR) for wild type and HYP mice infused with vehicle or SPR4-peptide (see also Figure 4 ).
| Bone | ||||||
| mRNA | WT versus HYP | Vehicle versus SPR4 | ||||
| Vehicle | WT | HYP | ||||
| Mean | Std Error | Mean | Std Error | Mean | Std Error | |
| FGF23 | 107.7* | ±30.39 | 1.6* | ±0.25 | NS | ― |
| MEPE | 6.2* | ±1.41 | −3.5* | ±1.01 | NS | ― |
| DMP1 | 5.2* | ±1.61 | NS | ― | −4.4* | ±0.65 |
| SOST | 6.1* | ±1.80 | −3.6* | ±0.96 | −11.6* | ±2.33 |
| VEGF | NS | ― | NS | ― | NS | ― |
| GAPDH | −6.2* | ±1.72 | 5.6* | ±1.02 | 59.7* | ±17.91 |
| Osteocalcin | NS | ― | −3.6* | ±0.76 | NS | ― |
| Cyclophilin | NS | ― | NS | ― | NS | ― |
| Plin-2 | −2.1* | ±0.33 | −1.8* | ±0.25 | 1.8* | ±0.22 |
| ESP | 2.7* | ±0.81 | −1.9* | ±0.17 | NS | ― |
| FAM20C | 2.9* | ±0.30 | −3.0* | ±0.68 | −2.9* | ±0.59 |
| ENPP1 | 2.3* | ±0.36 | −2.0* | ±0.18 | −1.9* | ±0.20 |
Column headings represent; WT = wild type mice, HYP = X-linked hypophosphatemic rickets mice, SPR4 = infused SPR4-peptide and Vehicle = Saline infused. For gene analysis mice were sacrificed on day 28 and mRNA prepared from bone marrow stromal cell depleted femurs as detailed in methods (N = 6). For qRT-PCR gene analysis fold differences in expression calculated by the Pfaffl method [163] were statistically analyzed for significance using the One Sample t-test and the Wilcoxon Signed rank-test with theoretical means set to 1. Results for all tests were considered to be significantly different at p<0.05 and are denoted with an asterisk (*) superscript. The fold changes in expression and standard error of the means (SEM) of WT-VE versus HYP-VE, WT-VE versus WT-SPR4 and HYP-VE versus HYP-SPR4 are shown in columns 1, 2 and 3 as indicated in the headings. ND = Not done, NS = Not Significant. Index : FGF23 = Fibroblast Growth Factor 23; MEPE = Matrix Extracellular Phosphoglycoprotein with ASARM -motif; DMP1 = Dentin Matrix Protein 1; SOST = Sclerostin; VEGF = Vascular Endothelial Growth factor; GAPDH = Glyceraldehyde 3-phosphate dehydrogenase; PHEX = Phosphate-regulating gene with Homologies to Endopeptidases on the X chromosome; Osteocalcin = Bone gamma-carboxyglutamate (gla) protein; Cyclophilin = peptidylprolyl isomerase A (cyclophilin A); Plin-2 = Perlipin-2; ESP = Osteotesticular protein tyrosine phosphatase (OST-PTP); FAM20C = Family with sequence similarity 20, member C Kinase also known as DMP4; ENPP1 = Ectonucleotide Pyrophosphatase Phosphodiesterase 1.