Export of Human Proinsulin in E.coli

Yup Kang(강엽) 한국생물공학회 1996 KSBB Journal Vol.11 No.2

방선균에서 유래한 YHB-2017 (Genistein)의 인슐린 분비 촉진 작용 기전

곽원재(Won Jae Kwag),박유희(You Hoi Park),박준철(Jun Chul Park),이병규(Byung Kyu Lee),강엽(Yup Kang),최태부(Tae Boo Choe) 한국생물공학회 2006 KSBB Journal Vol.21 No.6

기관지천식과 관련된 기도상피세포 자가항원의 단백체 분석: 세포배양 분획을 활용한 표적단백질의 규명 방법

이혜아 ( Hye Ah Lee ),이연정 ( Yeon Jeong Lee ),권별 ( Byul Kwon ),최길순 ( Gil Soon Choi ),박한정 ( Han Jung Park ),예영민 ( Young Min Ye ),박해심 ( Hae Sim Park ),강엽 ( Yup Kang ),남동호 ( Dong Ho Nahm ) 대한천식알레르기학회 2008 천식 및 알레르기 Vol.28 No.3

Background: Involvement of the autoimmune mechanism has been suggested for the pathogenesis of bronchial asthma and several autoantigens which are associated with bronchial asthma have been identified. Objective: To identify novel asthma-associated autoantigens by proteomic analysis of proteins which are extracted by the cultured cell fractionation method according to the physical affinity of airway epithelial cells(A549) to the culture matrix. Method: Autoantigens were screened with serum samples from patients with severe asthma and the target autoantigens were identified by mass spectrometry. Result: Cultured A549 cells were differentially fractionated into easily detachable floating cell fraction and firmly attached cell fraction. Easily detachable cell fraction containing senescent cell and necrotic cell debris had many detectable asthma-related autoantigens when screened by immunoblot analysis using IgG antibodies from patients with severe asthma. In mass spectrometry analysis of 95-kDa autoantigen, ailpha-actin 4 was identified as a new airway epithelial autoantigen which was recognized by IgG autoantibody from a patient with severe asthma. This was reconfirmed by using specific antibody. Conclusion: Proteomic analysis of the airway epithelial cells using the differential fractionation method according to the physical characteristics of cultured airway epithelial cells may be a novel method for the identification of additional asthma- related autoantigens. (Korean J Asthma Allergy Clin Immunol 2008;28:192-198)

TRIP-16 화합물의 베타세포 당지질독성 해독 기전 분석

박선미(Sun mi Park),정대연(Dae youn Jeong),구진모(Jin mo Ku),황윤정(Yoon Jung Hwang),최성이(Sung E Choi),강엽(Yup Kang),정귀완(Kwi wan Jeong) 대한약학회 2016 약학회지 Vol.60 No.6

Gradual deterioration of pancreatic beta cells is a conundrum still to be resolved in the diabetes field. The toxicity manifested by high level of glucose and saturated fatty acid (SFA), which is collectively termed as glucolipotoxicity, has been accepted as a predominant factor of beta cell dysfunction or failure. In this study, we examined the effect of TRIP (Triazolo[ 3,4-a]phthalazine)-16, a compound derivatized from TRIP which had been identified in a high throughput screening to discover chemicals protecting INS-1 cells from glucolipotoxicity. We also investigated its mode of action to reduce glucolipotoxicity, especially regarding modulation of lipid metabolism. From a series of cell-based experiments, we observed that TRIP-16 reduced fatty acid-induced triglyceride (TG) accumulation, whereas it increased oxidation rate of glucose or palmitate. The compound also reduced reactive oxygen species generated by palmitate and upregulated expression levels of carnitine palmitoyltransferase-1a (CPT-1a), peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC- 1α) and uncoupling protein 2 (UCP-2), implicating that it can facilitate mitochondrial energy metabolism to oxidize palmitate. In terms of beta cell functioning, TRIP-16 augmented glucose-stimulated insulin secretion (GSIS) per se. Taken together, our data strongly suggest that TRIP-16 can be a potential drug candidate for prevention of type 2 diabetes through beta cell protection.

자가면역 당뇨모델인 NOD mouse의 ontogeny에 따른 GAD 유전자의 특이한 발현양상

고인영,강엽 대한당뇨병학회 1997 Diabetes and Metabolism Journal Vol.21 No.3

Background: Glutamic acid decarboxylase(GAD; EC 4.1.1.15), one of the major B-cell autoantigens in IDDM, is an enzyme which catalyzes the synthesis of major inhibitory neurotransmitter, r-aminobutyric acid (GARA), in the mammalian brain, pancreas and other organs. Two isoforms of GAD, GAD65 and GAD67, have been identified which differ in their intracellular localization. Autoantibodies to GAD have been detected several years before the clinical onset of IDDM, implicating GAD as a leading autoantigen which somehow correlated with the pathogenesis of IDDM. We have determined the characteristics of GAD isoform expression in the pancreas of NOD mouse, an animal model extensively employed in IDDM study, using RT-PCR and Southern blot methods. Methods: Pancreas was obtained from female NOD mouse(neonate, 4, 8, 12, 16, 20 week-old) and age-matched female ICR mouse. Total cellular RNA was I.solated by acid guanidinium thiocyanate method and employed in the RT-PCR amplification using GAD65- and GAD67-specific primer designed in our laboratory. The PCR product was blotted onto the nylon membrane and subjected to Southern analysis using 32P-ATP labelled hybridization probe. Results: In NOD pancreas, GAD67 was expressed six times higher than GAD65 at neonatal stage. Then, the expression was dramatically decreased from 4 weeks when the pancreatic insulitis begins to occur. After 12 weeks of age, both GAD67 and GAD65 expression was almost undetectable. However, in control ICR mouse, there were no significant differenees between GAD65 and GAD67 expression throughout the ages. And, the expression of both GAD65 and OAD67 was not decreased with ages in contrast to NOD mouse. Conclusion: In this experiment, we found that the expression of GAD isoforms in NOD mouse shows distinct pattern in comparison to that of control ICR mouse. The expression of GAD67 was significantly higher than GAD65 in neonatal NOD mouse while, in control ICR mouse, same level of GAD isoforrns expression was observed. This finding clearly sug- gested the possibility that the expression of GAD isoforms in diabetic NOD mouse is quite distinct and may somehow play a role in the pathogenesis of diabetes although the precise mechanism remains to be unveiled. In addition, our data also supported the hypothesis that expressional pattern, and, if possible, ' the etiophysiological function of GAD isoforms in NOD mouse pancreas may be quite different from that in human pancreas.

레트로바이러스의 표면단백질 : 인슐린의존형 당뇨병의 동물모델인 NOD 쥐의 혈청과 반응하는 새로운 자가항원 A New Autoantigen Reactive with Non Obese Diabetic (NOD) Mice Sera

김경수,김기환,김현만,윤지원,강엽 아주대학교 1997 아주의학 Vol.2 No.2

IDDM (Insulin dependent diabetes mellitus) is believed to be an autoimmune disease and characterized by the immune activation against insulin-producing pancreatic beta cell. The identification and characterization of new autoantigens reactive with an activated immune System would heip to elucidate the pathogenic mechanism of this disease. Several autoantigens are trying to apply for diagnosis and prevention of IDDM. The NOD (non obese diabetic) mice have been the best model for studying the pathogenesis of human IDDM. To identify new autoantigens reactive with activated humoral immunity of NOD mice, the lambda gt11 cDNA library was constructed from NOD-derived pancreatic beta cell (MIN6N8a: mouse insulinoma cell) and screened with prediabetic NOD sera. Mine positive dones were selected from 2x10^(5) phage plaques. The 5'-end sequencing and homology searching showed that six clones from nine clones had over 98% sequence homolgy with the retroviral envelope gene. Full sequendng reveated that the cloned gene was a fragment of ecotropic retrovirus (emv-3) envelope gene. To confirm the immunoreactivity of doned retroviral envelope protein, the cloned gene fragment was expressed in an E.coli expression vector System. Western blotting showed that the recombinant envelope protein fragment also reacted with prediabetic NOD sera.

성장호르몬이 결핍된 흰쥐에서 성장호르몬 투여가 체조성 및 당대사에 미치는 영향

김현만,허갑범,이현철,이관우,정윤석,강엽,박덕배,양승오 대한내분비학회 1997 Endocrinology and metabolism Vol.12 No.1

Background: It is well known that growth hormone(GH) stimulates animal growth, but studies on metabolic effects of growth hormone have recently been increasing. The purpose of this study was to clarify the effects of growth hormone treatment on body composition and glucose metabolism in hypophysectomized growth hormone-deficient rats. Methods: The 20-week-old rnale Sprague-Dawley rats were hypophysectomized and replaced with cortisol and thyroxine for 8 weeks, then administered with recombinant human growth hormone for 2 weeks. Group 1 consisted of intact controls(n 15), while group 2 consisted of hypophysectomized controls(n 12), and group three consisted of those with GH treatment(n 13). The body weights, body composition, blood glucose levels, plasma insulin-like growth factor-I (IGF-I) levels, euglycemic hyperinsulinemic clamp test, and glycogen synthase activities in gastrocnemius muscle were measured before and after growth hormone treatment. Results: Plasma IGF-I levels in GH-treated group increased to intact control group levels after 2 weeks of GH treatment. There were significant changes in body composition after the treatment (fat mass significantly decreased and lean body mass significantly increased). There were no changes in glucose metabolism in peripheral tissue after 2 weeks of GH treatment. Condusion: Human GH treatment(4 IU/kg/day) in adult hypophysectomized GH-deficient rats changed the body composition, but did not alter the glucose metabolism in peripheral tissue. (J Kor Soc Endocrinol 12:53-60, 1997)