• Mass Spectrometry Letters
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• v.10 no.2
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• pp.61-65
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• 2019

Korean ginseng (Panax ginseng Meyer) is a traditional herb used across the world to treat various diseases. Although, red ginseng is this herb's most famous product and has demonstrated diverse pharmacological activities, white ginseng (WG) is another ginseng product that is made fresh and individually regulated in Eastern Asia. Red and white ginseng show different characteristics due to distinct processing steps despite originating from the same plant, and the drug interactions induced by WG have not been well documented. Selegiline is a selective monoamine oxidase (MAO) inhibitor used as an antidyskinetic and antiparkinsonian agent. Here we developed a quantification method for selegiline in mouse plasma using a C8 stationary phase in triple quadrupole-mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM). The validated LC-MS/MS method was successfully applied to determine the potential interaction with WG extract (0.1 g/kg/day) pre-administered for 4 weeks. The $AUC_{0-240min}$ of selegiline was altered due to a decrease in the absorption of selegiline with repeated administration of WG extract.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.397-415
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• 2002

This paper deals with a crucial mechanism for interaction of basic drugs and cardiac glycosides at the hepatic uptake level. Available literature data is provided and new material is presented to picture the differential transport inhibition of bulky (type2) cationic drugs by a number of cardiac glycosides in rat liver. It is shown that the so called organic anion transporting peptide 2 (oatp2) is the likely interaction site: differential inhibition patterns as observed in oocytes expressing oatp2, could be clearly identified also in isolated rat hepatocytes, isolated perfused rat liver and the rat in vivo. The anticipation of transport interactions at the hepatic clearance level should be based on data on the relative affinities of interacting substrates for the transport systems involved along with knowledge on the pharmacokinetics of these agents as well as the chosen dose regimen in the studied species. This review highlights the importance of multispecific tranporter systems such as OATP, accommodating a broad spectrum of organic compounds of various charge, implying potential transport interactions that can affect body distribution and organ clearance.

• Journal of Sasang Constitutional Medicine
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• v.24 no.4
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• pp.84-91
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• 2012

Objectives : The purpose of this study is to investigate the inhibitory or inductive potentials of Yuldahanso-tang (YDT) and Chungsimyonja-tang (CST), herbal formulas for Taeeumin, on cytochrome P450 (CYP450) drug metabolizing enzyme. The mechanisms for the herbal formula-drug interaction has not been well reported in spite of the chance for co-administration with conventional drugs. Methods : To evaluate the interaction potential of YDT-drug or CST-drug, the fluorescence-based enzyme assays on CYP450 isozymes including CYP3A4, CYP2C19, CYP2D6 and CYP2E1 were established in vitro. The inhibitory effects of herbal formulas were characterized with $IC_{50}$ values. Results : YDT showed inhibitory effects on CYP2D6 and CYP2E1-mediated metabolism, while it exhibited week inhibition on CYP3A4 and CYP2C19 relatively. CST exerted relatively weak inhibitory effects on the four CYP450 isozymes compared to that of YDT. Conclusions : These results suggest that the herbal formula-drug interaction could be occur when YDT are co-administered with drugs mediated by CYP2D6 or CYP2E1.

• Journal of Integrative Natural Science
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• v.5 no.1
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• pp.32-37
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• 2012

Chemokine receptor antagonists have potential applications in field of drug discovery. Although the chemokine receptors are G-protein-coupled receptors, their cognate ligands are small proteins (8 to 12 kDa), and so inhibiting the ligand/receptor interaction has been challenging. The application of structure-based in-silico methods to drug discovery is still considered a major challenge, especially when the x-ray structure of the target protein is unknown. Such is the case with human CCR2 and CCR5, the most important members of the chemokine receptor family and also a potential drug target. Herein, we review the success stories of combined receptor modeling/mutagenesis approach to probe the allosteric nature of chemokine receptor binding by small molecule antagonists for CCR2 and CCR5 using Rhodopsin as template. We also urged the importance of recently available ${\beta}2$-andrenergic receptor as an alternate template to guide mutagenesis. The results demonstrate the usefulness and robustness of in-silico 3D models. These models could also be useful for the design of novel and potent CCR2 and CCR5 antagonists using structure based drug design.

• Korean Journal of Community Nutrition
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• v.3 no.1
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• pp.76-93
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• 1998

Three hundred sixty-two(male 131, female 231) elderly aged over 65 in Chungb- uk area were interviewed to determine the disease states and drug usage patterns. The prebalence of disease was 78% and women reported more chronic diseases(83%) than men(71%). Elderly who live with spouse and have an occupation have a lower rate of disease. Average number of diseases of the elderly was $1.8\pm{1.1}$, and women$(2.1\pm{1.3)}$ have significantly higher average number of diseases than that of men$(1.4\pm{0.7)}$. Also the elderly in urban areas$(2.1\pm{1.4)}$ have significantly higher number of diseases than that of the elderly in rural areas$(1.6\pm{0.9)}$. Arthritis, hypertension, cardiovascular and gastric diseases were the most frequently listed chronic diseases in order for both men and women. Anemia and fracture of bone were relatively higher in women than in men. Particularly, the arthritis of the urban elderly have a rate of 1.5 times higher than that of the rural elderly. Fifty-two percent of the elderly were currently using drugs ; among drug users 71.2% used prescription drugs and 20.5% used nonprescription drugs. The average number taken per person was 2.1$\pm$1.4 and there was no sex or age difference. However, the elderly in rural areas $(2.7\pm{1.7)}$ consumed a significantly higher number of drugs than those in urban areas$(1.7\pm{0.7)}$. The average number of prescripti- on drugs taken was 2.0$\pm$1.4 while the average of nonprescription drugs taken was $(1.3\pm{0.6)}$. Analgesics and antihypertensive drugs were most commonly used. Vitamin and analgesics were the most frequently used self-prescribed drugs. It was noted that potential adverse drug interaction by concominant drug consumption for arthritis and antihypensive drug, abuse of digestants and antiacid without treatment of the underlying disease, and misuse of quick-acting bowel medications were problematic for the elderly. In addition drugs used for the elderly have some adverse effect on the digestive system. The types and composition of drugs used by the elderly were identified and presented. Medication compliance was poor and 13.5% reported adverse reactions such as edema, heartburn, nausea, and difficulty with eating. Seventeen percent of the elderly obtained drugs arranged by those other than medical staff. Also, even among those elderly who obtained drugs prescribed by a doctor, 69.1% of subjects had not receive instruction about potential adverse reactions. These results suggest that nutritional problems related to drug usage might exist and so dietitians, either individually or as members of health teams, need to have a better understanding of drug-nutrient interaction and closer supervision, and drug information/education service should therefore be provided to prevent or minimize adverse drug reaction in elderly users of medication.

• Journal of Integrative Natural Science
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• v.6 no.3
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• pp.138-142
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• 2013

The HIV-1 envelope glycoprotein gp120 plays a vital role in the entry of the virus into the host cells. The crucial role of the glycoprotein suggests gp120 as potential drug target for the future antiviral therapies. Identification of the binding mode of small drug like compounds has been an important goal in drug design. In the current study we attempt to propose binding mode of indole derivatives in the binding pocket of gp120. These derivatives are reported to inhibit HIV-1 by acting as attachment inhibitors that bind to gp120 and prevent the gp120-CD4 interaction and thus inhibit the infectivity of HIV-1. To elucidate the molecular basis of the small molecules interactions to inhibit the glycoprotein function we employed the molecular docking simulation approach. This study provides insights to elucidate the binding pattern of indole-based gp120 inhibitors and may help in the rational design of novel HIV-1 inhibitors with improved potency.

• YAKHAK HOEJI
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• v.57 no.3
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• pp.194-198
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• 2013

In the present study we evaluated drug-drug interaction potential of ambroxol and cetirizine mediated by inhibition of CYP isoforms including CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4 using pooled human liver microsomes (HLMs). As measured by liquid chromatography-electrospray ionization tandem mass spectrometry, cetirizine and ambroxol inhibited significantly CYP2E1 but the maximal inhibition was approximately 36% at 10 ${\mu}M$ cetirizine and 28% at 3 ${\mu}M$ ambroxol. In addition, CYP2D6 activity was decreased to approximately 83% of control activity in pooled HLM incubated with 3 ${\mu}M$ ambroxol. Activities of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, and CYP3A4 were not significantly inhibited by cetirizine and ambroxol. Considering their maximal plasma concentration in human ($C_{max}$ of cetirizine is approximately 0.67 ${\mu}M$ and $C_{max}$ of ambroxol is 0.044 ${\mu}M$), these two drugs have very low possibility in drug-drug interaction by CYP inhibition in clinical situations.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2008.04a
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• pp.89-99
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• 2008

GPCRs are large families of cell surface receptors that transmit signals through conformational changes upon ligand activation and an interaction with the heterotrimeric G-proteins. GPCRs regulate the cell-signaling pathways and participate in the regulation of physiological processes through the G-proteins defined by their ${\alpha}$ subunits. A family of 20 G protein-coupled receptors (GPCRs) that provide a large class of tractable drug targets for new anti-inflammatory drugs and, in certain instances, for the treatment of the inflammatory indications such as atherosclerosis, rhinitis, asthma, pulmonary disease and arthritis. In view of the important findings showing that $G{\alpha}_{12}/G{\alpha}_{13}$ regulate the various cellular processes such as actin-stress fiber formation, neurite retraction, platelet aggregation, gene induction, and apoptosis, we became interested in whether, after coupling to the activated GPCRs, the G-proteins and their downstream molecules might be involved in the pathologic processes of chronic inflammatory diseases (e.g., liver fibrosis). In this symposium, the possible link of the G-proteins with the pathophysiology will be discussed with the aim of finding potential new drug targets.

• Journal of Pharmaceutical Investigation
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• v.40 no.spc
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• pp.19-31
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• 2010

Orally administrated drugs permeate the biological membrane by various transport mechanisms. The oral absorption potential is closely related to the physicochemical properties of the drug and interaction with the physiological factors surrounding the site of absorption. Assessment of the drug membrane permeability is an integral part of the early stage drug developmental process. Appropriate selection of the permeability screening method at the right stage of drug development process is important in achieving successful developmental outcomes. This review aims at introducing currently available in vitro and in vivo screening methods for the membrane permeability assessment.

• BMB Reports
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• v.49 no.1
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• pp.18-25
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• 2016

Recent evidence has indicated that nano-sized vesicles called "exosomes" mediate the interaction between cancer cells and their microenvironment and play a critical role in the development of cancers. Exosomes contain cargo consisting of proteins, lipids, mRNAs, and microRNAs that can be delivered to different types of cells in nascent as well as distant locations. Cancer cell-derived exosomes (CCEs) have been identified in body fluids such as urine, plasma, and saliva from patients with cancer. Although their content depends on tumor type and stage, CCEs merit consideration as prognostic and diagnostic markers, as vehicles for drug delivery, and as potential therapeutic targets because they could transport various oncogenic elements. In this review, we summarize recent advances regarding the role of CCEs in cancer invasion and metastasis, as well as its potential clinical applications. [BMB Reports 2016; 49(1): 18-25]