Stability of Extemporaneously Prepared Hydroxycarbamide Oral Suspensions.

Hydroxycarbamide, available as tablets, is a pharmacological agent for fetal hemoglobin induction such as sickle cell anemia. The need for alternative dosage form options for patients unable to take tablets led hospital pharmacies to prepare solutions and suspensions. The objective of this study was to determine the stability of hydroxycarbamide in Ora-Plus in combination with either Ora-Sweet or Ora-Sweet SF, Ora-Blend, or Ora-Blend SF suspending agents. The studied samples were compounded into 100-mg/mL suspensions and stored in 60-mL amber glass bottles at room (22°C to 25°C) or refrigerated (4°C to 8°C) temperature. Samples were assayed at each time point out to 120 days by a stability-indicating high-performance liquid chromatography method. The samples were examined for any change in color, odor, visual microbiology, and pH on initial and final day of analysis. At least 90% of hydroxycarbamide concentration remained in all suspensions at the end of the 120-day study period in both conditions. There was no appreciable change in color, odor, or taste. The pH values of suspensions stored at 25°C changed by at least 1 unit at the end of the study period. Based on the data collected, the beyond-use date of these suspensions is 120 days when stored in 60-mL amber glass bottles at both temperature storage conditions.

Stability study of oral pediatric idebenone suspensions.

Adapted forms for administration to infants are limited. The proposed study was performed to propose oral liquid formulations of idebenone in Ora-Plus and either Ora-Sweet or Ora-Sweet SF, Ora-Blend, Ora-Blend SF and Inorpha. Each formulation was stored in 30 ml amber glass bottle at 5 or 25 °C for 90 days. Idebenone contents in these suspensions, determined by a stability-indicating high-performance liquid chromatography method, remained stable at least 90 days in Inorpha when stored at the two temperatures. In Ora-Blend, the stability was estimated at 14 days and in other suspensions at 20 days at the two temperatures. After 90 days storage, the pH of Ora-Plus and Ora-Sweet or Ora-Sweet SF changed between -0.10 and -0.25 units. For others suspensions, the pH changes were not significant (< -0.09 unit). No change was observed in color, odor or visual microbiology. To conclude, we recommended the use of idebenone in Inorpha vehicle stable for at least 90 days at 25 °C.

Intestine-specific regulation of PPARalpha gene transcription by liver X receptors.

Liver X receptor-alpha (LXRalpha) and LXRbeta are ligand-activated transcription factors belonging to the nuclear receptor superfamily. They have been identified as key players in cholesterol homeostasis and lipid and glucose metabolism as well as immune and inflammatory responses. In the small intestine, LXRs have been shown not only to regulate cholesterol absorption and excretion but also to promote high-density lipoprotein biogenesis via the ATP-binding cassette A1 signaling pathway. Here, using gene expression assays, we identified PPARalpha as an intestine-specific LXR target gene. Chronic administration of LXR synthetic agonists led to a significant increase of PPARalpha mRNA levels in the small intestine but not in the liver. In addition, this specific PPARalpha gene up-regulation occurred in the duodenum, jejunum, and ileum in a dose-dependent manner and translated at the protein level as demonstrated by Western blot analysis. Furthermore, PPARalpha gene induction was completely abolished in LXR-deficient mice. Finally, the physiological relevance of LXR-mediated PPARalpha up-regulation in the small intestine was assessed in PPARalpha-deficient mice. Administration of a synthetic LXR agonist to wild-type mice led to the induction of several PPARalpha target genes including PDK4 and CPT1. Those effects were completely abolished in PPARalpha-deficient mice, demonstrating the biological relevance of this LXR-PPARalpha transcriptional cascade. Taken together, these results demonstrate that PPARalpha is an intestine-specific LXR target gene and suggest the existence of a transcriptional cross talk between those members of the nuclear receptor superfamily.