• YAKHAK HOEJI
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• v.57 no.6
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• pp.412-419
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• 2013

Drug discovery and development processes are time consuming and costly endeavors. It has been reported that on average it takes 10 to 15 years and costs more than $ 1billion to bring a molecule from discovery to market. Compounds fail for various reasons but one of the significant reasons that accounts for failures in clinical trials is poor prediction/understanding of pharmacokinetics and drug metabolism in human. In an effort to improve the number of compounds that exhibit optimal absorption, distribution, metabolism, elimination (ADME), and pharmacokinetic properties in human, drug metabolism, pharmacokinetic scientists have been continually developing new technologies and compound screening strategies. Over the last few years, accelerator mass spectrometry (AMS) and its applications to preclinical/clinical pharmacokinetics and ADME studies have significantly increased, particularly for new chemical/biological entities that are difficult to support with conventional radiolabel studies. In this review, the application of AMS for micro-dosing, micro-tracer absolute bioavailability, mass balance and metabolite profiling studies will be discussed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.4
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• pp.898-906
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• 2007

This study was to evaluate the effects of oral administration of Processed Sulphur on Hepatotoxicity. Processed Sulphur was administered orally to rats for 28 days. We measured the body and liver weight index, heamtological and biomedical parameters. We also observed the histopathological changes of liver in rats. No significant differences in body weight, liver weight index, heamtological and biomedical parameters and histopathological changes of hepatocyte between control and Processed Sulphur fed group were found. Our data indicate that hepatotoxicity was not caused by oral medication of Processed Sulphur up to 60mg/200g/day for 28 days in rats. Therefore, Processed Sulphur appears to be safe and non-toxic in these studies and a no-observed adverse effect level (NOAEL) in rats is established at 60mg/200g/day. The data could provide satisfactory preclinical evidence of safety to launch clinical trial on standardized formulation of mineral extracts.

• Journal of Pharmaceutical Investigation
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• v.27 no.2
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• pp.139-143
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• 1997

Epidermal growth factor (EGF) is a mitogen which activate the proliferation of basal cells in skin, which implicate the wound healing in severe skin damage such as burn. To carry out the preclinical test for the pharmacological action of EGF, EGF in transdermal delivery system must be stable. Since EGF is a protein susceptible to proteolysis and unstable in aqueous solution, in vitro stabilization of EGF is prerequisite for the formulation. In this study, effect of additives on the stability of EGF is investigated in vitro. The stability of EGF in aqueous solution was enhanced with the various water-soluble polysaccharides such as HPMC, sorbitol, mannitol and dextrin. EGF was successfully extracted from the ointment with 5% HPMC solution, and EGF in aqueous solution and ointment was also successfully stabilized with 5% HPMC. The ointments prepared with different amount of EGF were applied on the damaged dorsal skin of rats for the determination of optimal concentration of EGF. The ointment with EGF $(10\;{\mu}g/g)$ showed good wound healing action on the damaged skin of rats.

• Journal of Society of Preventive Korean Medicine
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• v.5 no.1
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• pp.57-75
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• 2001

This study was conducted to improve the current regulation guidelines for developing traditional Korean medicines with effectiveness and productivity, in order to cope with the upcoming ICH on specifications on oriental herbal drugs. Also, major purposes of this study are to motivate R&D and to pioneer foreign markets for domestic herbal drug companies. First, after examining concepts of traditional Korean medicines and comparing the numbers and differentiation of herbal drugs registered on Pharmacopeia among Korea, China, and Japan, the current new drug development requirements for traditional Korean medicines were reviewed in detail, followed by comparison of foreign regulation systems including USA, EU, China, and Japan. Second, empirical cases on failure of development for new traditional Korean medicines under the current regulation system in the domestic companies including Dong-A, Kwangdong, and Samchondang, were collected and analyzed. As a result, hanbangsaengyak, the new category for traditional Korean medicines was newly developed on the basis of scientification of data between saengyak and hanyak, from the perspectives of harmonization between oriental medicine and western medicine and of balance between food and drug, in terms of industrialization, publicity, modernization, and effectiveness of administration. In addition, the new regulation requirements for the new hanbangsaengyak preparations were discussed by establishing principles of reinforcing preclinical test and of simplifying clinical trials in Korea. Finally, the further researches to articulate the complete specifications for pre-clinical and clinical requirements for traditional Korean medicines were strongly suggested.

• Biomolecules & Therapeutics
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• v.7 no.3
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• pp.292-299
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• 1999

SKI 2053 R, cis-Malonato [(4R, 5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane] platinum(II), is a newly developed antitumor platinum complex derived from cisplatin. Preclinical studies suggest that it may have greater antitumor activity and lower toxicity than cisplatin. Effects of test agent on general toxicity of does and embryonic development of Fl fetuses were investigated in rabbits. Sixty eight New Zealand white rabbits were distributed among three treated groups and a control group. SKI 2053R was administered intravenously to pregnant rabbits from days 6 to 18 of gestation at dose levels of 0, 0.67, 2.0, or 6.0 mg/kg/day. The pregnant does were subjected to the caesarean section on day 28 of gestation. No treatment-related changes in clinical signs, body weight, food consumption, and necropsy findings were observed in all groups. Fl fetuses showed no changes related to the treatment of SKI 2053R, except that an increase in the incidence of skeletal variations were observed at 6.0 mg/kg. There were no signs of material toxicity or embryotoxicity at 0.67 and 2.0 mg/kg. The results show that the administration of 6.0 mg/kg SKI 2053R induces skeletal variations in fetuses and that the no observed adverse effect levels(NOAELS) of SKI 2053R are considered to be over 6.0 mg/kg for does and 2.0 mg/kg for Fl fetuses in rabbits.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.6
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• pp.427-448
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• 2019

Nociceptin/orphanin FQ (N/OFQ) and its receptor, nociceptin opioid peptide (NOP) receptor, are localized in brain areas implicated in depression including the amygdala, bed nucleus of the stria terminalis, habenula, and monoaminergic nuclei in the brain stem. N/OFQ inhibits neuronal excitability of monoaminergic neurons and monoamine release from their terminals by activation of G protein-coupled inwardly rectifying $K^+$ channels and inhibition of voltage sensitive calcium channels, respectively. Therefore, NOP receptor antagonists have been proposed as a potential antidepressant. Indeed, mounting evidence shows that NOP receptor antagonists have antidepressant-like effects in various preclinical animal models of depression, and recent clinical studies again confirmed the idea that blockade of NOP receptor signaling could provide a novel strategy for the treatment of depression. In this review, we describe the pharmacological effects of N/OFQ in relation to depression and explore the possible mechanism of NOP receptor antagonists as potential antidepressants.

• Journal of Microbiology and Biotechnology
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• v.31 no.9
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• pp.1281-1287
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• 2021

Clinical and preclinical studies have reported that Lactobacillus gasseri BNR17, a probiotic bacterial strain isolated from human breast milk, reduces body weight and white adipose tissue volume. In order to further explore the actions of L. gasseri BNR17, we investigated the anti-menopausal effects of L. gasseri BNR17 in an ovariectomized (OVX) rat model. The serum alanine aminotransferase levels of the rats in the OVX-BNR17 group were lower than those of the rats in the OVX-vehicle only (OVX-Veh) group. Upon administration of L. gasseri BNR17 after ovariectomy, calcitonin and Serotonin 2A levels increased significantly, whereas serum osteocalcin levels showed a decreasing tendency. Compared to the rats in the OVX-Veh group, those in the OVX-BNR17 group showed lower urine deoxypyridinoline levels, lower pain sensitivity, and improved vaginal cornification. Furthermore, L. gasseri BNR17 administration increased bone mineral density in the rats with OVX-induced femoral bone loss. These results suggest that L. gasseri BNR17 administration could alleviate menopausal symptoms, indicating that this bacterium could be a good functional probiotic for managing the health of older women.

• Toxicological Research
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• v.35 no.1
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• pp.65-74
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• 2019

Tetrahydrocurcumin (THC) is a major metabolite of curcumin, which is obtained from Curcuma longa. THC has various benefits and overcomes the bioavailability issue of curcumin. To establish it as a pharmacologically active molecule, its safety profile has to be determined. Thus, the present study aimed to determine the preclinical safety profile of THC in a 90-day subchronic and reproductive/developmental toxicity study in Wistar rats. THC at oral doses of 100, 200, and 400 mg/kg was administered daily for 90 days. Rats in the recovery group were kept for 14 days after treatment termination. The animals were observed for treatment-related morbidity, mortality, and changes in clinical signs, clinical pathology, and histopathology. In the reproductive/developmental toxicity study, THC at 100, 200, and 400 mg/kg was administered orally to rats and the reproductive/developmental parameters in adult male and female rats and pups were observed. THC at up to 400 mg/kg/day of did not have any significant effect on all parameters in male and female rats in both toxicity studies. Thus, 400 mg/kg/day can be considered as the no-observed-adverse-effect-level of THC in rats.

• Journal of Gastric Cancer
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• v.19 no.3
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• pp.235-253
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• 2019

Gastric cancer (GC) is one of the deadliest malignancies in the world. Currently, clinical treatment decisions are mostly made based on the extent of the tumor and its anatomy, such as tumor-node-metastasis staging. Recent advances in genome-wide molecular technology have enabled delineation of the molecular characteristics of GC. Based on this, efforts have been made to classify GC into molecular subtypes with distinct prognosis and therapeutic response. Simplified algorithms based on protein and RNA expressions have been proposed to reproduce the GC classification in the clinical field. Furthermore, a recent study established a single patient classifier (SPC) predicting the prognosis and chemotherapy response of resectable GC patients based on a 4-gene real-time polymerase chain reaction assay. GC patient stratification according to SPC will enable personalized therapeutic strategies in adjuvant settings. At the same time, patient-derived xenografts and patient-derived organoids are now emerging as novel preclinical models for the treatment of GC. These models recapitulate the complex features of the primary tumor, which is expected to facilitate both drug development and clinical therapeutic decision making. An integrated approach applying molecular patient stratification and patient-derived models in the clinical realm is considered a turning point in precision medicine in GC.

• Psychiatry investigation
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• v.15 no.12
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• pp.1130-1134
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• 2018

Objective Trichotillomania is a relatively common illness whose neurobiology is poorly understood. One treatment for adult trichotillomania, n-acetyl cysteine (NAC), has antioxidative properties, as well as effects on central glutamatergic transmission. Preclinical models suggest that excessive oxidative stress may be involved in its pathophysiology. Methods Adults with trichotillomania provided a blood sample for analysis of compounds that may be influenced by oxidative stress [glutathione, angiotensin II, ferritin, iron, glucose, insulin and insulin growth factor 1 (IGF1), and hepcidin]. Participants were examined on symptom severity, disability, and impulsivity. The number of participants with out-of-reference range oxidative stress measures were compared against the null distribution. Correlations between oxidative stress markers and clinical measures were examined. Results Of 14 participants (mean age 31.2 years; 92.9% female), 35.7% (n=5) had total glutathione levels below the reference range (p=0.041). Other oxidative stress measures did not have significant proportions outside the reference ranges. Lower levels of glutathione correlated significantly with higher motor impulsiveness (Barratt Impulsiveness Scale sub-score) (r=0.97, p=0.001). Conclusion A third of patients with trichotillomania had low levels of glutathione, and lower levels of glutathione correlated significantly with higher motor impulsiveness. Because NAC is a precursor for cysteine, and cysteine is a rate limiting step for glutathione production, these results may shed light on the mechanisms through which NAC can have beneficial effects for impulsive symptoms. Confirmation of these results requires a suitable larger follow-up study, including an internal normative control group.