Animal Experimentation and Research Commons^™

A Two Compartment Pharmacokinetic Model Describes The Intra‐Articular Delivery And Retention Of Rhprg4 Following Acl Transection In The Yucatan Mini Pig, Mark Hurtig, Iman Zaghoul, Heather Sheardown, Tannin A. Schmidt, Lina Liu, Ling Zhang, Khaled A. Elsaid, Gregory D. Jay

Pharmacy Faculty Articles and Research

Treatment of the injured joint with rhPRG4 is based on recent observations that inflammation diminishes expression of native PRG4. Re‐establishing lubrication between pressurized and sliding cartilage surfaces during locomotion promotes the nascent expression of PRG4 and thus intra‐articular (IA) treatment strategies should be supported by pharmacokinetic evidence establishing the residence time of rhPRG4. A total of 21 Yucatan minipigs weighing ∼55 Kg each received 4 mg of 131I‐rhPRG4 delivered by IA injection 5 days following surgical ACL transection. Animals were sequentially euthanized following IA rhPRG4 at 10 mins (time zero), 24, 72 hrs, 6, 13 and 20 days later. The …

Brain Endothelial Erythrophagocytosis And Hemoglobin Transmigration Across Brain Endothelium: Implications For Pathogenesis Of Cerebral Microbleeds, Rudy Chang, Juan Castillo, Alexander C. Zambon, Tatiana B. Krasieva, Mark J. Fisher, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Peripheral endothelial cells are capable of erythrophagocytosis, but data on brain endothelial erythrophagocytosis are limited. We studied the relationship between brain endothelial erythrophagocytosis and cerebral microhemorrhage, the pathological substrate of MRI-demonstrable cerebral microbleeds. To demonstrate the erythrophagocytic capability of the brain endothelium, we studied the interactions between brain endothelial cells and red blood cells exposed to oxidative stress in vitro, and developed a new in vitro cerebral microbleeds model to study the subsequent passage of hemoglobin across the brain endothelial monolayer. Using multiple approaches, our results show marked brain endothelial erythrophagocytosis of red blood cells exposed to oxidative stress compared …

Uplc-Ms/Ms Analysis Of Dextromethorphan-O-Demethylation Kinetics In Rat Brain Microsomes, Barent N. Dubois, Reza Mehvar

Pharmacy Faculty Articles and Research

Formation of dextrorphan (DXT) from dextromethorphan (DXM) has been widely used to assess cytochrome P450 2D (CYP2D) activity. Additionally, the kinetics of CYP2D activity have been well characterized in the liver microsomes. However, studies in brain microsomes are limited due to the lower microsomal content and abundance of CYP2D in the brain relative to the liver. In the present study, we developed a micro-scale enzymatic incubation method, coupled with a sensitive UPLC-MS/MS assay for the quantitation of the rate of DXT formation from DXM in brain microsomes. Rat brain microsomes were incubated with different concentrations of DXM for various times. …

Aging Exacerbates Development Of Cerebral Microbleeds In A Mouse Model, Rachita K. Sumbria, Mher Mahoney Grigoryan, Vitaly Vasilevko, Annlia Paganini-Hill, Kelley Kilday, Ronald Kim, David H. Cribbs, Mark J. Fisher

Pharmacy Faculty Articles and Research

Background: Cerebral microhemorrhages (CMH) are commonly found in the aging brain. CMH are also the neuropathological substrate of cerebral microbleeds (CMB), demonstrated on brain MRI. Recent studies demonstrate the importance of systemic inflammation in CMH development, but the relationships among inflammation, aging, and CMH development are not well-defined. In the current study, we hypothesized that the pathogenesis of inflammation-induced CMH in mice differs by age.

Methods: We studied young (3 months, n = 20) and old (18 months, n = 25) C57BL/6 mice injected with low-dose lipopolysaccharide (LPS; 1 mg/kg, i.p.) or saline at 0, 6, and 24 …