• Biomolecules & Therapeutics
• /
• 제29권3호
• /
• pp.249-262
• /
• 2021

The most effective way to control newly emerging infectious disease, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, is to strengthen preventative or therapeutic public health strategies before the infection spreads worldwide. However, global health systems remain at the early stages in anticipating effective therapeutics or vaccines to combat the SARS-CoV-2 pandemic. While maintaining social distance is the most crucial metric to avoid spreading the virus, symptomatic therapy given to patients on the clinical manifestations helps save lives. The molecular properties of SARS-CoV-2 infection have been quickly elucidated, paving the way to therapeutics, vaccine development, and other medical interventions. Despite this progress, the detailed biomolecular mechanism of SARS-CoV-2 infection remains elusive. Given virus invasion of cells is a determining factor for virulence, understanding the viral entry process can be a mainstay in controlling newly emerged viruses. Since viral entry is mediated by selective cellular proteases or proteins associated with receptors, identification and functional analysis of these proteins could provide a way to disrupt virus propagation. This review comprehensively discusses cellular machinery necessary for SARS-CoV-2 infection. Understanding multifactorial traits of the virus entry will provide a substantial guide to facilitate antiviral drug development.

• 한국군사과학기술학회지
• /
• 제24권3호
• /
• pp.348-355
• /
• 2021

Hantaan virus(HTNV) causes hemorrhagic fever with renal syndrome(HFRS) with a case fatality rate ranging from <1 to 15 % in human. Hantavax^Ⓡ is a vaccine against the Hantavirus, which has been conditionally approved by the Ministry of Food and Drug Safety(MFDS). However, only 50 % of volunteers had neutralizing antibodies 1 year following the boost. Effective antiviral treatments against HTNV infection are limited. Hantaviruses generally cause asymptomatic infection in adult mice. On the other hand, infection of suckling and newborn mice with hantaviruses causes lethal neurological diesease or persistant infection, which is different from the disease in humans. The development of vaccines and antiviral strategies for HTNV has been partly hampered by the lack of an efficient lethal mouse model to evaluate the efficacy of the candidate vaccines or antivirals. In this report, we established a lethal mouse model for HTNV, which may facilitate in vivo studies on the evaluation of candidate drugs against HTNV. The median lethal dose value of HTNV was calculated by probit analysis of deaths occurring within two weeks. Five groups of ten ICR mice were injected intracranially with serial 2-fold dilutions (from 50 to 3.125 PFU/head) of HTNV. Mice injected with HTNV began to die at 8 days post-infection. The lethal dose required to kill 50 % of the mice (LD₅₀) was calculated to be 2.365 PFU/head.

• Journal of Pharmaceutical Investigation
• /
• 제24권2호
• /
• pp.73-83
• /
• 1994

Applications of liposomes as a drug carrier for the oral delivery of poorly-absorbable macromolecular drugs have been limited, because of their instability in gastrointestinal environments including pH, bile salts, and digestive enzymes. Two polysaccharides, dextran(DX) and pullulan(PL), were introduced to the preformed liposomes in order to enhance the stability. Palmitoyl derivatives of polysaccharides, palmitoyldextran(PalDX) and palmitoylpullulan(PalPL), were synthesizd and introduced to the liposomes during preparation for the same purpose of stability. The effects of these polysaccharides coating were evaluated basically by physical properties of particle size distribution and optical microscopy, then compared with uncoated liposomes by the observations of both in vitro stability and in vovo absorption characteristics. The geometric mean diameters of polysaccharide-coated liposomes were greater than that of uncoated liposome, showing the outermost polysaccharide-coated layer under the optical microscopy. In vitro stabilities of uncoated or polysaccharides-coated liposomes were measured by turbidity changes in various pH buffer solutions containing sodium choleate as bile salts. While uncoated liposome was very sensitive to bile salts, polysaccharides-coated liposomes were stable in relatively higher concentrations of sodium choleate, giving the results of better stability of PalDX- and PalPL-coated liposomes than that of DX- and PL-coated liposomes. After liposomal encapsulation of acyclovir(ACV), an antiviral agent as a model drug, it has been administered orally to rats as dose of ACV 40 mg/kg. Plasma concentrations of ACV were assayed by HPLC and analyzed by model-independent pharmacokinetics. Pharmacokinetic parameters of Cmax, tmax, and [AUC] have been compared.

• Molecules and Cells
• /
• 제44권9호
• /
• pp.688-695
• /
• 2021

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a global health concern. Various SARS-CoV-2 vaccines have been developed and are being used for vaccination worldwide. However, no therapeutic agents against coronavirus disease 2019 (COVID-19) have been developed so far; therefore, new therapeutic agents are urgently needed. In the present study, we evaluated several hepatitis C virus direct-acting antivirals as potential candidates for drug repurposing against COVID-19. Theses include asunaprevir (a protease inhibitor), daclatasvir (an NS5A inhibitor), and sofosbuvir (an RNA polymerase inhibitor). We found that asunaprevir, but not sofosbuvir and daclatasvir, markedly inhibited SARS-CoV-2-induced cytopathic effects in Vero E6 cells. Both RNA and protein levels of SARS-CoV-2 were significantly decreased by treatment with asunaprevir. Moreover, asunaprevir profoundly decreased virion release from SARS-CoV-2-infected cells. A pseudoparticle entry assay revealed that asunaprevir blocked SARS-CoV-2 infection at the binding step of the viral life cycle. Furthermore, asunaprevir inhibited SARS-CoV-2 propagation in human lung Calu-3 cells. Collectively, we found that asunaprevir displays broad-spectrum antiviral activity and therefore might be worth developing as a new drug repurposing candidate for COVID-19.

• 한국임상약학회지
• /
• 제29권1호
• /
• pp.56-60
• /
• 2019

Oseltamivir is an antiviral medication prescribed to prevent and treat influenza A and B. A case from a community pharmacy in Korea was reported for an adverse event associated with oseltamivir administration. A 20-month-old boy had psychiatric symptoms after receiving 2 doses of oseltamivir. Therefore, an evaluation of whether the psychiatric symptoms were caused by oseltamivir was required. To determine whether the adverse event resulted from the administrated medication or other factors, three tools were used: the Naranjo scale, the Korean causality assessment algorithm (Ver.2), and the World Health Organization-Uppsala Monitoring Center (WHO-UMC) criteria. The psychiatric symptoms occurred after oseltamivir administration, and were attenuated after oseltamivir termination. A possible cause of the psychiatric symptoms is high fever, but information on the body temperature of the patient was not sufficient. Therefore, it was unclear whether there were other nonpharmacological causes of adverse drug reaction. For these reasons, in terms of causality, the results evaluated by the three tools represented, "possible", "probable", and "probable/likely", respectively.

• 생명과학회지
• /
• 제34권6호
• /
• pp.408-417
• /
• 2024

원화(Daphne genkwa (Siebold & Zucc))의 50% 에탄올 추출물인 PB-81이 소 로타바이러스 설사병 환축에서 설사병의 치료효과와 바이러스 증식 억제 효과가 나타나는가를 확인하였다. PB-81에 의해 상피세포주인 A549 세포와 혈액세포주인 NK92 세포에서 각각 IFN-β와 IFN-γ가 유도되는 것을 확인하였다. PB-81의 바이러스의 증식억제 효과를 확인하기 위해 PB-81을 MBDK 세포에 바이러스의 감염 전, 동시, 감염 후에 투여하는 세 가지 경우에서 바이러스 억제효과를 확인한 결과 PB-81을 투여한 모든 경우에서 바이러스가 억제되었으며, 바이러스 감염 전에서 투여하는 경우에서 가장 좋은 바이러스 억제효과가 나타났다. 마우스에서의 독성검사에서는 투여최대용량인 20 mg/mL에서도 독성에 따른 부작용이 나타나지 않았다. 소 로타바이러스 설사병 환축 16두와 대조군 4두를 대상으로 한 치료효과 검증에는 20 mg/5 mL 용량의 PB-81을 투여한 결과, PB-81을 투여한 모든 소 로타바이러스 설사병 환축이 완치되었으며 PB-81의 투여 후에 완치까지 소요된 기간은 PB-81투여군이 평균 2.25일이었고, PB-81을 투여하지 않은 대조군이 6.5일로 PB-81의 투여에 의한 소 로타바이러스 설사병의 치료효과가 나타나는 것을 확인하였으며 PB-81을 투여한 모든 환축에서 부작용이 검출되지 않았다.

• 한국균학회지
• /
• 제27권3호통권90호
• /
• pp.237-241
• /
• 1999

잔나비걸상 Elfvingia applananta 자실체의 수용성성분 EA의 varicella zoster virus(Oka strain; VZV/oka)에 대한 항바이러스효과를 plaque reduction assay에 따라 실험한 결과 EA는 용량의존적으로 plaque 형성을 억제하였으며 $EC_{50}$는 $464.14\;{\mu}g/ml$이었다. EA와 단백질성 항바이러스제인 interferon(IFN) alpha 및 IFN gamma와의 병용시험 결과, 단독처리시와 병용처리시에 m(slope) value가 서로 유사한 값을 보였으므로 이들은 상호 배타적인 약물(mutually exclusive drug)임을 알 수 있었고, IFN alpha와의 병용시 combination index(CI)는 f(a)가 0.50에서 0.90인 유효농도 범위내에서 $0.83{\sim}1.09$의 값을 나타내어 부분적 상승 또는 상가효과를 보였으며, IFN gamma와의 병용시에는 $1.20{\sim}1.24$를 나타내어 길항효과를 보였으므로, IFN alpha와의 병용이 IFN gamma와의 병용보다 더 우수한 병용효과를 나타내었다.

• 한국응용약물학회:학술대회논문집
• /
• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
• /
• pp.176-176
• /
• 1994

Moraceae comprise a large family of sixty genera and neary 1,400 specieses, including important groups such as Artocarpus, Morus, and Ficus. In particular, Morus(mulberry) is a small genus of tree and shrubs found in temperate and subtropical regions of the Northern hemishere and has been widely cultivated in China and Korea, In addition, the root bark of mulberry tree have been used as an antiphlogic, diuretic, and expectorant in white medicine, and the crude drug is known as "Sangbaikpi" in Korea. Recently, some papers have been published reporting the hypotensive effect, antiviral effect, antifungal effect, inhibitory effect of cAMP-phosphodiesterase, and anticancer effect of this extract. Little is known about that Cortex mori could have been an antiallergic effect. The purpose of this study was the development of an antiallergic agent with an antiallergic effect from Cortex mori. For this, several in vivo and in vitro experimental models were used. Results are 1) Cortex mori inhibited the compound 48/80-induced degranu-lation, histamine release and calcium uptake of rat peritoneal mast cells, 2) compound 48/80-induced anaphylactic shock and cutaneous reaction were significantly inhibited by pretreatment of Cortex mori, and 3) Cortex mori inhibited the ovalbumin-induced late astmatic reaction. From the above results it is suggested that Cortex mori has some substances with an antiallergic activity. Our final purpose of this study is to develope the new drug with an antiallergic activity from Cortex mori

• Biomolecules & Therapeutics
• /
• 제28권4호
• /
• pp.311-319
• /
• 2020

Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a newly emerging viral disease with fatal outcomes. However, no MERS-CoV-specific treatment is commercially available. Given the absence of previous structure-based drug discovery studies targeting MERS-CoV fusion proteins, this set of compounds is considered the first generation of MERS-CoV small molecule fusion inhibitors. After a virtual screening campaign of 1.56 million compounds followed by cell-cell fusion assay and MERS-CoV plaques inhibition assay, three new compounds were identified. Compound numbers 22, 73, and 74 showed IC₅₀ values of 12.6, 21.8, and 11.12 µM, respectively, and were most effective at the onset of spike-receptor interactions. The compounds exhibited safe profiles against Human embryonic kidney cells 293 at a concentration of 20 µM with no observed toxicity in Vero cells at 10 µM. The experimental results are accompanied with predicted favorable pharmacokinetic descriptors and drug-likeness parameters. In conclusion, this study provides the first generation of MERS-CoV fusion inhibitors with potencies in the low micromolar range.

• Journal of Pharmaceutical Investigation
• /
• 제34권3호
• /
• pp.169-176
• /
• 2004

Acyclovir(ACV) is an important antiviral drug used extensively against infections caused by herpes viruses, especially herpes simplex and varicella zoster. Because of high crystallinity and large particle size, solubility of intact ACV is very low in water(1.3 mg/ml). The goal of this work is to enhance the solubility of ACV. To make solid dispersion, Polyethyleneglycol, Hydroxyprophylmethylcelluose and Polyvinylpyrrolidone were used as polymer carriers in this work. Polymer carriers and drug were dissolved in acetic acid. And then spray drying method and freeze drying method were used as solvent extraction. Morphology, crystallization and functional group were characterized using SEM, XRD and FT-IR. The result of in vitro test showed the sample using PVP as polymer carrier had higher dissolution rate(up to 466%) than intact ACV.