• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.12a
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• pp.16-44
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• 2020

Cancer is the second leading cause of death in the world. According to the 2018 reports, one in six people worldwide is reported to die as a result of cancer. The discovery of anticancer drugs has been utilized extensively, but there has been no report on excellent selective activity in cancer cells. The discovery of bioactive substances from marine sponges has been the limelight in the pharmaceutical field over the past decade owing to the production of many bioactive compounds from the sponges to protect themselves against the environment. On top of that, marine sponges also produced cytotoxic compounds such as terpenoids, alkaloids, steroids, and peptides which suggests that marine sponges have high potential in the development of anticancer drugs. Thus, this study aimed to obtain new cytotoxic compounds from S. siphonella in Egypt and Arenoscelra sp. and Gelliodes sp. in Vietnam, and further investigation of the extract from these marine sponges led to isolation of ten new compounds and 21 known compounds. Chapter 1 will discuss about the isolation and structure elucidation of eight new polyacetylene derivatives from S. siphonella and their cytotoxic activities. The isolation and structural elucidation of one new polybrominated iododiphenyl ether from Arenosoclea sp. as well as cytotoxic activities of the isolated compounds will be reported in chapter 2. Finally, isolation and structure elucidation of new compounds from the marine sponge Gelliodes sp. and their cytotoxic activities will be discussed in chapter 3.

• Journal of Microbiology and Biotechnology
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• v.16 no.5
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• pp.651-660
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• 2006

Natural products are a rich source of biologically active small molecules and a fertile area for lead discovery of new drugs [10, 52]. For instance, 5% of the 1,031 new chemical entities approved as drugs by the US Food and Drug Administration (FDA) were natural products between 1981 and 2002, and another 23% were natural product-derived molecules [53]. These molecules have evolved through millions of years of natural selection to interact with biomolecules in the cells or organisms and offer unrivaled chemical and structural diversity [14, 37]. Nonetheless, a large percentage of nature remains unexplored, in particular, in the marine and microbial environments. Therefore, natural products are still major valuable sources of innovative therapeutic agents for human diseases. However, even when a natural product is found to exhibit biological activity, the cellular target and mode of action of the compound are mostly mysterious. This is also true of many natural products that are currently under clinical trials or have already been approved as clinical drugs [11]. The lack of information on a definitive cellular target for a biologically active natural product prevents the rational design and development of more potent therapeutics. Therefore, there is a great need for new techniques to expedite the rapid identification and validation of cellular targets for biologically active natural products. Chemical genomics is a new integrated research engine toward functional studies of genome and drug discovery [40, 69]. The identification and validation of cellular receptors of biologically active small molecules is one of the key goals of the discipline. This eventually facilitates subsequent rational drug design, and provides valuable information on the receptors in cellular processes. Indeed, several biologically crucial proteins have already been identified as targets for natural products using chemical genomics approach (Table 1). Herein, the representative case studies of chemical genomics using natural products derived from microbes, marine sources, and plants will be introduced.

• Korean Journal of Biological Psychiatry
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• v.1 no.1
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• pp.7-16
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• 1994

I will try to serve as the basis for the development of a clinical therapeutic guideline of antipsychotic drugs. Knowing that many patients fail standard treatment recommendations, either because of insufficient efficacy or intolerance to adverse effects, led us to emphasize the importance of the guideline. The clinicians continually assimilate new information about recent advances, including : novel agents targeted to impact specific components of various neurotransmitter systems ; combination strategies ; alternative uses of existing agents ; and specialized requirements of a growing number of identified diagnostic subtypes. The cost to benefit ratio must always be considered when developing a therapeutic guideline.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.105-110
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• 1999

In our continuing search for new antineoplastic agents from natural products, one hundred and thirty-five herbal drugs were extracted with petroleum ether/ether (1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3(human ovary adenocarcinoma) cell lines. Among them, fifteen kinds of ether extracts, eighteen kinds of ethyl acetate extracts and seven kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml,$ while ten kinds of ether extracts, thirteen kinds of ethyl acetate extracts and six kinds of methanol extracts demonstrated significant cytotoxic activities against SK-OV-3 cell lines at the above same concentration.

• Korean Journal of Pharmacognosy
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• v.29 no.4
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• pp.323-330
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• 1998

For the search of new antineoplastic agents from natural resources, two hudred and one kinds of oriental medicinal drugs were extracted with petroleum ether/ether(1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3 (human ovary adenocarcinoma) cell lines. Among them, thirty kinds of ether extracts, forty-one kinds of ethyl acetate extracts and nine kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml$. And also, twenty-four kinds of ether extracts, thirty-one kinds of ethyl acetate extracts and six kinds of methanol extracts showed significant cytotoxic activities against SK-OV-3 cell lines at the same concentration.

• Interdisciplinary Bio Central
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• v.2 no.2
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• pp.3.1-3.4
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• 2010

In the present research, we assessed the utility of the structural information of drugs for predicting human in vivo intrinsic clearance from in vitro intrinsic clearance data obtained by human hepatic microsome experiment. To compare with the observed intrinsic clearance, human intrinsic clearance values for 51 drugs were estimated by the classical methods using in vivo-in vitro scale-up and by the new methods using the in vitro experimental data and selected molecular descriptors of drugs by the forward selection technique together. The results showed that taking consideration of molecular descriptors into prediction from in vitro experimental data could improve the prediction accuracy. The in vitro experiment is very useful when the data can estimate in vivo data accurately since it can reduce the cost of drug development. Improvement of prediction accuracy in the present approach can enhance the utility of in vitro data.

• Korean Journal of Biological Psychiatry
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• v.4 no.2
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• pp.155-161
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• 1997

Serotonin has been implicated in the etiology of many disease states and may be particularly important mental illness, such as depression, anxiety, schizophrenia, sleep disorders, suicide, eating disorders, obsessive compulsive disorders, migraine and others. Many currently used treatments of these disorders are thought to act by modulating serotonergic function. The identification of many serotonin subtypes, most of which have been shown to have functional activity and differential distribution, has stimulated considerable effort into synthesizing selective ligands(drugs) to help understand their significance. This should understand the role of serotonin in mental disorders and these new drugs can be studied alone and in combination with other treatments in order to clarify the parameters of drug use for the clinical effect.

• Toxicological Research
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• v.17
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• pp.211-216
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• 2001

Drugs can have various adverse effects on the immune system including unintended immun-osuppression, induction of both drug-specific immune responses (including drug allergies) and non-specific immunostimulation (including autoimmune reactions), and direct activation of effector mechanisms (such as histamine release). As a practical matter, the Center for Drug Evaluation (CDER) relies on standard non-clinical toxicology studies to detect unintended immunosuppression. Specific assays using guinea pigs and mice are available to identify drugs that can induce immune-mediated dermal hypersensitivity reactions. Respiratory and systemic hypersensitivity and autoimmune reactions are more difficult to model in non-clinical studies. Unintended nonspecific immunstimulation can be detected in animal studies. CDER is currently developing specific guidance for evaluating potential drug immunotoxicity.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.1
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• pp.1-9
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• 2012

Because the average human life span has recently increased, the number of patients who are diagnosed with neurodegenerative diseases has escalated. Recent advances in stem cell research have given us access to unlimited numbers of multi-potent or pluripotent cells for screening for new drugs for neurodegenerative diseases. Neural stem cells (NSCs) are a good model with which to screen effective drugs that increase neurogenesis. Recent technologies for human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) can provide human cells that harbour specific neurodegenerative disease. This article discusses the use of NSCs, ESCs and iPSCs for neurodegenerative drug screening and toxicity evaluation. In addition, we introduce drugs or natural products that are recently identified to affect the stem cell fate to generate neurons or glia.

• Korean Deer Journal
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• no.14
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• pp.12-21
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• 1991

Several experiments were carried for the purpose of establishing the basis for the quality evaluation of deer horn. Deer horn originated from China, New Zealand, Soviet and Alaska were used as objectives and some constituents involved in deer horn were as