The Effect of Progesterone Dose on Gene Expression after Traumatic Brain Injury

Abstract

Microarray-based transcriptional profiling was used to determine the effect of progesterone in the cortical contusion (CCI) model. Gene ontology (GO) analysis then evaluated the effect of dose on relevant biological pathways. Treatment (vehicle, progesterone 10 mg/kg or 20 mg/kg given i.p.) was started 4 h post-injury and administered every 12 h post-injury for up to 72 h, with the last injection 12 hr prior to death for the 24 h and 72 h groups. In the CCI-injured vehicle group compared to non-injured animals, expression of 1,114, 4,229, and 291 distinct genes changed > 1.5-fold ( p < 0.05) at 24 h, 72 h, and 7 days, respectively. At 24 h, the effect of low-dose progesterone on differentially expressed genes was < 20% the effect of higher dose compared to vehicle. GO analysis identified a significant effect of low-and high-dose progesterone treatment compared to vehicle on DNA damage response. At 72 h, high-dose progesterone treatment compared to vehicle affected expression of almost twice as many genes as did low-dose progesterone. Both low-and high-dose progesterone resulted in expression of genes regulating inflammatory response and apoptosis. At 7 days, there was only a modest difference in high-dose progesterone compared to vehicle, with only 14 differentially expressed genes. In contrast, low-dose progesterone resulted in 551 differentially expressed genes compared to vehicle. GO analysis identified genes for the low-dose treatment involved in positive regulation of cell proliferation, innate immune response, positive regulation of anti-apoptosis, and blood vessel remodeling.

Gestational Age-Dependent Changes in Gene Expression of Metabolic Enzymes and Transporters in Pregnant Mice

“…Processing of the RNA samples was carried out according to the AffymetrixGeneChip Whole Transcript Sense Target labeling protocol (http://www.affymetrix.com/index. affx) as reported previously (Anderson et al, 2011). The arrays were scanned with an AffymetrixGeneChip 3000 scanner.…”

“…These genes were selected because they either demonstrated large changes in the microarray data or are important for xenobiotic metabolism and transport. Fluorogenic 59 nuclease-based assays were employed as previously described (Anderson et al, 2011;Cole et al, 2011;Stamper et al, 2011). Actb (b-actin) amplification plots derived from serial dilutions of an established reference sample were used to create a linear regression formula to calculate expression levels.…”

A Comparison of the Effects of Nicotinamide and Progesterone on Functional Recovery of Cognitive Behavior following Cortical Contusion Injury in the Rat

“…Initial pharmacokinetic studies were employed to determine the optimal dosing of nicotinamide 30 and progesterone. 23 Specifically, the dosing regimen in the present study aimed to compare nicotinamide (75 mg/kg, i.p. loading dose, followed by continuous infusion 12 mg/kg/h, s.c. over 72 h) with progesterone (10 mg/kg, i.p.…”

“…12 The progesterone samples were analyzed using an enzyme linked immunoassays (ELISA) (R&D Systems Inc, Minneapolis, MN, and VWR International, West Chester, PA). 23 …”

“…Therefore, the main object of this study was to compare clinically relevant doses of nicotinamide and progesterone (both low and high) to each other following unilateral CCI, utilizing a 72 h dosing regimen. The dosing regimens of progesterone that were examined in the present study were selected based on our previous pharmacokinetic study 23 and are similar to some in the published literature. 19,22 Drug concentrations were confirmed by serum analysis 72 h post-TBI, and the animals were tested with a battery of behavioral tests and then assessed for tissue loss.…”