Investigation of Solid Dosage Form Components Interaction Using Orthogonal Techniques- Discovery of New Forms of Sodium Stearyl Fumarate.

Physical or chemical interactions between drug product (DP) components can occur during manufacturing and/or upon storage; and may alter DP shelf life and performance. In this work a new Powder X-ray Diffraction (PXRD) peak was observed in DP under accelerated storage conditions. Due to the complex drug product matrix (including API, polymer, fillers, super disintegrant and lubricant), it was challenging to pinpoint the component(s) responsible for the new peak. In addition to PXRD, other orthogonal techniques including Differential Scanning Calorimetry (DSC), thermogravimetric analysis (TGA), dynamic vapor sorption (DVS), Solid State Nuclear Magnetic Resonance (SSNMR) and Infrared (IR) spectroscopy were employed in this investigation to understand the root cause mechanistically. Specifically, multi nuclei SSNMR (1H, 23Na, 13C) was instrumental in delineating the components of the matrix. We identified the root cause to be an acid base reaction occurring in the DP, whereby sodium ion in sodium stearyl fumarate (SSF) is replaced by proton leading to SSF form conversion. We also identified commercially available SSF to be a hydrate that can dehydrate to an anhydrous form upon heating. In general, the same techniques can be used to investigate interactions of any multi component solid dosage forms.

The effects of social defeat on behavior and dopaminergic markers in mice.

The present study investigated the effects of chronic social defeat stress on several behavioral parameters, and the expression of dopaminergic markers, i.e., dopamine D1 receptors (D1Rs), dopamine D2 receptors (D2Rs), and dopamine and cyclic adenosine 3',5'-monophosphate-regulated phosphoprotein-32 (DARPP-32), in the prefrontal cortex (PFC), amygdala (AMY), and hippocampus (HIP) of mouse brains. After 10days of social defeat stress, the defeated mice were divided into two groups: one group underwent a series of behavioral tests. The other group was sacrificed on the 11th day and tissue samples were collected for Western blotting. The behavioral tests comprised tests of locomotion, light/dark preference, social interaction, as well as the novel object recognition test (NORT), Morris water maze, and forced swimming test (FST). We measured the expression of D1Rs, D2Rs, total DARPP-32, phospho-Thr34 or Thr75-DARPP-32 using Western blotting. The defeated mice showed increased anxiety- and depression-like behaviors, and impaired cognition. No significant differences in D1Rs and D2Rs expression were shown between defeated and control mice in any area studied. A significantly increased expression in total DARPP-32, and phospho-DARPP-32 was observed in the PFC or AMY of defeated mice. These data suggest that alterations in dopaminergic markers may be involved in anxiety- and depression-like behaviors, and cognitive impairment induced by social defeat stress.

Effects of chronic mild stress in female bax inhibitor-1-gene knockout mice.

OBJECTIVE: The anti-apoptotic protein Bax inhibitor-1 (BI-1) is a regulator of apoptosis linked to endoplasmic reticulum (ER) stress, and BI-1(-/-) mice exhibit increased sensitivity to tissue damage. The purpose of this study was to investigate the role of BI-1 in the pathogenesis of chronic mild stress (CMS)-induced depression-like behaviors in BI-1(-/-) mice. METHODS: We delivered CMS for 2 or 6 weeks in BI-1-knockout and wild-type mice. Control groups of BI-1-knockout and wild-type mice were left undisturbed. The measured parameters were sucrose consumption at weeks 1, 2, 3, 4, 5, and 6, spontaneous locomotion, and a forced swimming test (FST) at weeks 2 and 6. RESULTS: Significant decreases in sucrose consumption and increases in immobility time in the FST were observed in both stress groups compared with the non-stress groups. Interestingly, at week 2, but not at week 6, BI-1(-/-)-stress mice showed less sucrose intake and greater immobility time than did BI-1(+/+)-stress mice. CONCLUSION: These results suggest that BI-1 may play role in protecting against the depressogenic effects of CMS in the short term, but not in the long term. Further study is required to deepen understanding of the role of BI-1 in protecting against depression.

Effects of Chronic Mild Stress in Female Bax Inhibitor-1-Gene Knockout Mice

OBJECTIVE: The anti-apoptotic protein Bax inhibitor-1 (BI-1) is a regulator of apoptosis linked to endoplasmic reticulum (ER) stress, and BI-1-/- mice exhibit increased sensitivity to tissue damage. The purpose of this study was to investigate the role of BI-1 in the pathogenesis of chronic mild stress (CMS)-induced depression-like behaviors in BI-1-/- mice. METHODS: We delivered CMS for 2 or 6 weeks in BI-1-knockout and wild-type mice. Control groups of BI-1-knockout and wild-type mice were left undisturbed. The measured parameters were sucrose consumption at weeks 1, 2, 3, 4, 5, and 6, spontaneous locomotion, and a forced swimming test (FST) at weeks 2 and 6. RESULTS: Significant decreases in sucrose consumption and increases in immobility time in the FST were observed in both stress groups compared with the non-stress groups. Interestingly, at week 2, but not at week 6, BI-1-/--stress mice showed less sucrose intake and greater immobility time than did BI-1+/+-stress mice. CONCLUSION: These results suggest that BI-1 may play role in protecting against the depressogenic effects of CMS in the short term, but not in the long term. Further study is required to deepen understanding of the role of BI-1 in protecting against depression.