• Journal of Life Science
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• v.26 no.10
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• pp.1153-1162
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• 2016

Termitomyces albuminosus (Berk.) Heim is a well-known wild edible mushroom in the southern region of China. Novel cerebrosides, termed termitomycesphins, isolated from EtOH extract of T. albuminosus have shown significant neuritogenic activity. Neurotrophic factors have been targeted as potential therapeutic drugs for the treatment of neurodegenerative disorders. However, before expanding their applications to include food or therapeutic agents in Korea, a safety evaluation of T. albuminosus is needed. Herein, in a repeated-dose 90-day oral toxicity study, rats were exposed to a basal diet of powder ground from dried T. albuminosus at dose levels of 5%, 2.5%, 1.25%, and 0%. The following endpoints were evaluated: clinical observation, body weight, gross and microscopic pathology, clinical chemistry, and hematology. Significant dose-dependent increases in the weight of the left kidney were observed, possibly due to the test substance. Based on toxicity-decision criteria for minor compound-related changes (no observed adverse effect level [NOAEL] and no observed effect level [NOEL]), NOAEL was observed in male rats at a dose of 5% of dried T. albuminosus powder, and NOEl was observed in female rats at the same dose. The results point to the safety and potential use of T. albuminosus as a nontoxic neurotrophic factor.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.7
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• pp.1135-1141
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• 1999

A large number of investigations have shown that changes in nutritional condition affect endocrine status in avian species. Herein, recent findings including novel peptides discovered by the development of the techniques in the field of molecular biology have been reviewed. The insulin-like growth factors (IGF-I and IGF-II) found in chickens have been characterized and shown to be 70 and 66 amino acid polypeptides, respectively. Plasma IGF-I level is very responsive to nutrition, Le. varying dietary proteins and energy intakes, and food restriction. Plasma IGF-II concentration is altered by nutritional deprivation to a much smaller extent than plasma IGF-I concentration. Almost all of the serum and tissue IGFs are found in a complex composed of IGF and IGF-binding protein (IGFBP). In the chicken plasma, the major IGFBP differs from that in mammalian plasma. The proglucagon mRNA encodes glucagon and two glucagon-like peptides (GLP-I and GLP-2). The intracerebroventricular administration of GLP-l strongly decreased food intake of chicks, and it was indicated that the inhibition of food intake by GLP-l was associated with neuropeptide Y, which is one of the neurotransmitters reported to enhance food intake.

• Biomolecules & Therapeutics
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• v.26 no.2
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• pp.201-209
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• 2018

G protein-coupled receptor 119 (GPR119) is expressed in the pancreas and gastrointestinal tract, and its activation promotes insulin secretion in the beta cells of the pancreatic islets as well as the secretion of glucagon-like peptide-1 (GLP-1) in intestinal L cells, consequently improving glucose-stimulated insulin secretion. Due to this dual mechanism of action, the development of small-molecule GPR119 agonists has received significant interest for the treatment of type 2 diabetes. We newly synthesized 1,2,4-triazolone derivatives of GPR119 agonists, which demonstrated excellent outcomes in a cyclic adenosine monophosphate (cAMP) assay. Among the synthesized derivatives, YH18968 showed cAMP=2.8 nM; in GLUTag cell, GLP-1secretion=2.3 fold; in the HIT-T15 cell, and insulin secretion=1.9 fold. Single oral administration of YH18968 improved glucose tolerance and combined treatment with a dipeptidyl peptidase 4 (DPP-4) inhibitor augmented the glucose lowering effect as well as the plasma level of active GLP-1 in normal mice. Single oral administration of YH18968 improved glucose tolerance in a diet induced obese mice model. This effect was maintained after repeated dosing for 4 weeks. The results indicate that YH18968 combined with a DPP-4 inhibitor may be an effective therapeutic candidate for the treatment of type 2 diabetes.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.298.2-298.2
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• 2003

The insulinotropic hormone, glucagons-like peptide-1 (GLP-1), which has been proposed as a new potential therapeutics for type-II diabetes, but this is metabolized extremely rapidly by the ubiquitous enzyme, dipeptidyl peptidase IV (DPP IV), forming a metabolite, which acts as an antagonist at the GLP-1 receptor. (omitted)

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2471-2474
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• 2009

• Journal of Pharmacopuncture
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• v.17 no.3
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• pp.40-49
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• 2014

Objectives: The gastric ulcer is a common disorder of the stomach and duodenum. The basic physiopathology of a gastric ulcer results from an imbalance between some endogenous aggressive and cytoprotective factors. This study examined whether Ganoderma lucidum pharmacopuncture (GLP) would provide protection against acute gastric ulcers in rats. Methods: Sprague-Dawley rats were divided randomly into 4 groups of 8 rats each: normal, control, normal saline (NP) and GLP groups. The experimental acute gastric ulcer was induced by using an EtOH/HCl solution and the normal group received the same amount of normal saline instead of ethanol. The NP and the GLP groups were treated once with injections of saline and GLP, respectively. Two local acupoints were used: CV12 (中脘) which is the alarm point of the Stomach Meridian, and ST36 (足三里), which is the sea point of the Stomach Meridian. The stomachs from the rats in each group were collected and analyzed for gross appearance and histology. Also, immunohistochemistry staining for BAX, Bcl-2 and TGF-${\beta}1$ was performed. Results: Histological observations of the gastric lesions in the control group showed comparatively extensive damage of the gastric mucosa and necrotic lesions had penetrated deeply into the mucosa. The lesions were long, hemorrhagic, and confined to the glandular portions. The lesions were measured microscopically by using the clear depth of penetration into the gastric mucosal surface. The length and the width of the ulcer were measured and the inhibition percentage was calculated. Wound healing of the acute gastric ulcer was promoted by using GLP, and significant alterations of indices in gastric mucosa were observed. Such protection was shown by gross appearance, histology and immunohistochemistry staining for BAX, Bcl-2 and TGF-${\beta}1$. Conclusion: These results suggest that GLP administered at CV12 and ST36 can provide significant protection to the gastric mucosa against an ethanol-induced acute gastric ulcer.

• Food Science and Industry
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• v.51 no.4
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• pp.302-312
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• 2018

Bioactive peptides generated from milk proteins play an important role in the prevention and alleviation of diabetes. Whey proteins possess direct insulinotropic effect by amino acids (especially branch chain amino acids) produced through its gastrointestinal digestion. Additionally, blood glucose level can be lowered by gut hormone which called incretin [glucose dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1)]. However, physiological effects of incretin readily disappeared by dipeptidyl peptidase-4 (DPP-4) causing degradation of GLP-1. Several DPP-4 inhibitors are currently used as therapeutic medicines for the treatment of type II diabetes. More than 60 natural peptide (2-14 amino acids) DPP-4 inhibitors were identified in milk proteins. Peptide DPP-4 inhibitors act as substrate inhibitor and delay breakdown of GLP-1 both in vitro and in vivo. This review summarizes nutritional quality of milk proteins, absorption and mode of action of bioactive peptides, and finally up-to-dated knowledge on DPP-4 inhibitory peptides derived from milk proteins.

• Toxicological Research
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• v.22 no.2
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• pp.109-116
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• 2006

Safety pharmacology studies are conducted to investigated the potential undesirable pharmacodynamic effects of a substance on physiological functions in relation to exposure in the therapeutic range and above. In the International Conference on Harmonisation (ICH), the guideline 'S7A: Safety Pharmacology Studies for Human Pharmaceuticals' has been developed and reached Step 5 of the ICH process in 2001. Now the Korea Food and Drug Administration (KFDA) are going to transfer 'The Guideline for General Pharmacology' into 'The Guideline for Safety Pharmacology'. Safety pharmacology studies should be performed in compliance with Good Laboratory Practice (GLP). Thus, the present paper reviews the Japanese GLP guidelines for pharmaceuticals to help the conduct and inspection of safety pharmacology studies in compliance with GLP. We also reviewed the ICH guidelines 'S7B revised : The Nonclinical Evaluation of the Potential for Delayed Ventricular Repolarization (QT Interval Prolongation) by Human Pharmaceuticals' and 'E14 : The Clinical Evaluation of QT/QTc Interval Prolongation and Proarrhythmic Potential for Non-antiarrhythmic Drugs' to apply our drug approval systems.

• Toxicological Research
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• v.34 no.3
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• pp.259-266
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• 2018

Glycomacropeptide (GMP), a whey protein of milk, has functions including differentiation and development of nervous system, and anticancer and antiviral effects. To develop new functions, N-acetylneuraminic acid (NANA) containing 7% sialic acid was separated from GMP to produce G-7%NANA. N-glycolylneuraminic acid (Neu5Gc) is another type of sialic acid separated from GMP, which has been linked to immune disorders and chronic inflammation-mediated diseases. Therefore, safety was a concern in the use of G-7%NANA in functional foods. To ensure safety, in this study, three genetic toxicity tests on G-7%NANA were conducted. In the reverse mutation test using Salmonella typhimurium TA98, TA100, TA1535, TA1537, and Escherichia coli WP2uvrA, and in the chromosome aberration test using CHO-K1 cells, no significant differences from negative control were found at all dose levels. Similarly, no dose-related differences were evident compared to negative control in the micronucleus test using ICR mice. There was no evidence of G-7%NANA-related genetic toxicity.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.8
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• pp.1160-1166
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• 2009

This study was conducted according to the single-factor design principle to investigate in vitro the effects of different glucagon-like peptide-2 (GLP-2) concentrations (0, $1{\times}10^{-11}$, $1{\times}10^{-10}$, $1{\times}10^{-9}$, $1{\times}10^{-8}$ and $1{\times}10^{-7}$ mol/L) on the morphology, proliferation and enzyme activity of intestinal enterocyte cells of 28-d-old weaned piglets. These cells were primary cultured in 4 pieces of 24-well cell culture plate. After having been grown for 48 h in culture media with hGLP-2, the ileal enterocyte cells of 28-d-old weaned piglets exhibited the typical characteristics of simple columnar epithelium. Compared with the control groups, the quantities of treated cells significantly increased (p<0.05) and their corresponding absorption values in 540 nm (MTT OD) also significantly increased (p<0.01). Likewise, lactic acid concentration, total protein content and protein retention significantly increased (p<0.05). $Na^{+}$, $K^{+}$-ATP enzyme activity was more active (p<0.05), although the activity of alkaline phosphatase, lactic acid dehydrogenase and creatine phosphokinase in culture media significantly decreased (p<0.01). To summarize, the results indicated that GLP-2 in vitro is capable of promoting the proliferation of intestinal enterocyte cells of 28-d weaned piglets, restraining their apoptosis and maintaining the integrity of their morphology.