P-Glycoprotein: A Focus on Characterizing Variability in Cardiovascular Pharmacotherapeutics

Repurposing colchicine's journey in view of drug-to-drug interactions. A review

Colchicine's medical evolution is historically bound to the Mediterranean basin, since remarkable researchers from this region underscored its valuable properties. With the passing of years colchicine became an essential pharmaceutical substance for the treatment of rheumatologic and cardiovascular diseases. In light of recent findings, the therapeutic value of colchicine has grown. In clinical practice, colchicine remains underutilized in view of its proven efficacy and safety. Its complex pharmacokinetics and multifaceted anti-inflammatory role remain under investigation. The current review addresses the safe administration of colchicine in view of key drug to drug interactions. Finally, we are briefly presenting colchicine's future potential applications.

Replacing the eleven native tryptophans by directed evolution produces an active P-glycoprotein with site-specific, non-conservative substitutions

P-glycoprotein (Pgp) pumps an array of hydrophobic compounds out of cells, and has major roles in drug pharmacokinetics and cancer multidrug resistance. Yet, polyspecific drug binding and ATP hydrolysis-driven drug export in Pgp are poorly understood. Fluorescence spectroscopy using tryptophans (Trp) inserted at strategic positions is an important tool to study ligand binding. In Pgp, this method will require removal of 11 endogenous Trps, including highly conserved Trps that may be important for function, protein-lipid interactions, and/or protein stability. Here, we developed a directed evolutionary approach to first replace all eight transmembrane Trps and select for transport-active mutants in Saccharomyces cerevisiae. Surprisingly, many Trp positions contained non-conservative substitutions that supported in vivo activity, and were preferred over aromatic amino acids. The most active construct, W(3Cyto), served for directed evolution of the three cytoplasmic Trps, where two positions revealed strong functional bias towards tyrosine. W(3Cyto) and Trp-less Pgp retained wild-type-like protein expression, localization and transport function, and purified proteins retained drug stimulation of ATP hydrolysis and drug binding affinities. The data indicate preferred Trp substitutions specific to the local context, often dictated by protein structural requirements and/or membrane lipid interactions, and these new insights will offer guidance for membrane protein engineering.

Telehealth electronic monitoring to reduce postdischarge complications and surgical site infections after arterial revascularization with groin incision

It is intuitive that postdischarge surgical complications are associated with increased patient dissatisfaction, and are directly associated with an increase in medical expenditures. It is also easy to make the connection that many post-hospital discharge surgical complications, including surgical site infections (SSIs), could be influenced or exacerbated by patient comorbidities. The authors of a recent study reported that female gender, obesity, diabetes, smoking, hypertension, coronary artery disease, critical limb ischemia, chronic obstructive pulmonary disease, dyspnea, and neurologic disease were significant predictors of SSIs after vascular reconstruction was performed. The main concern for optimal patient care, especially in geographically isolated areas of West Virginia, is to have early, expeditious, and prompt diagnosis of complications and SSI. This adjunct to existing approaches could lead to improved outcomes and patient satisfaction, minimizing third-party interventions and decreasing the total cost of care. It seems reasonable to believe that monitoring using telehealth technology and managing the general health care of patients after a hospital vascular intervention will improve overall health and reduce 30-day readmissions and SSIs.

Herb-Drug Interactions of Commonly Used Chinese Medicinal Herbs

With more and more popular use of traditional herbal medicines, in particular Chinese herbal medicines, herb-drug interactions have become a more and more important safety issue in the clinical applications of the conventional drugs. Researches in this area are increasing very rapidly. Herb-drug interactions are complicated due to the fact that multiple chemical components are involved, and these compounds may possess diverse pharmacological activities. Interactions can be in both pharmacokinetics and pharmacodynamics. Abundant studies focused on pharmacokinetic interactions of herbs and drugs. Herbs may affect the behavior of the concomitantly used drugs by changing their absorption, distribution, metabolism, and excretion. Studies on pharmacodynamics interactions of herbs and drugs are still very limited. Herb-drug interactions are potentially causing changes in drug levels and drug activities and leading to either therapeutic failure or toxicities. Sometime it can be fatal. The exposures to drugs, lacking of knowledge in the potential adverse herb-drug interactions, will put big risk to patients' safety in medical services. On the contrary, some interactions may be therapeutically beneficial. It may be used to help develop new therapeutic strategies in the future. This chapter is trying to review the development in the area of herb-drug interactions based on the recently published research findings. Information on the potential interactions among the commonly used Chinese medicinal herbs and conventional drugs is summarized in this chapter.