Colloguia : Mechanisms that mediate distribution of sodium channels at nodes of Ranvier

Eun Hye Joe 한국생화학분자생물학회 (구 한국생화학회) 1992 추계학술대회집 Vol.- No.-

Effect of Phosphorylation on the Interaction between Sodium Channels and Ankyrin

Joe, Eun-Hye,Angelides, K. J. 아주대학교 의과학연구소 1996 아주의학 Vol.1 No.1

Voltage-dependent sodium channels(NaChs) are distributed at the nodes of Ranvier in myelinated axons which are critical for generation and propagation of neural signal'. The nodal distribution of NaChs is partly maintained by linkage between NaChs and axolemmal cytoskeletal protein, ankyrin. To study how this linkage is regulated, we tested the effect of phosphorylation on their interaction because phosphorylation has been known to modulate interaction between proteins. NaChs and ankyrin were purified from rat brain and human red blood cells, respectively. Ankyrin was iodinated and both NaChs and iodinated ankyrin were phosphorylated by cAMP-dependent protein kinase. The radioactivity of iodinated ankyrin bound to NaChs was measured. Phosphorylation of each protein decreased the interaction, and particularly, phosphorylation of ankyrin had a greater effect than that of NaChs. Phosphorylation of both proteins had an additive effect. These results suggest that phosphorylation may be involved in regulation of the interaction between NaChs and ankyrin.

2000 ANNUAL MEETING OF THE KOREAN SOCIETY OF APPLIED PHARMACOLOGY & SYMPOSIUM : Trends in New Drug Development for Brain Diseases ; Activation Mechanisms and Endogenous Activators of Microglia

(Eun Hye Joe) 서울시립대학교 산업기술연구소 2000 국제학술SYMPOSIUM논문집 Vol.8 No.1

Poster Session 2 : Immunology Tumor Biology ; Rac1 contributes to maximal activation of STAT1 and STAT3 in IFN-γ-stimulated rat astrocytes

( Eun Jung Park ),( Kyung Ae Ji ),( Sae Bom Jeon ),( Woo Hyuck Choi ),( Inn Oc Han ),( Hae Jin Yoo ),( Jae Hong Kim ),( Ilo Jou ),( Eun Hye Joe ) 한국생화학분자생물학회 (구 한국생화학회) 2004 생화학분자생물학회 춘계학술발표논문집 Vol.2004 No.-

Overexpression of $AMPK{\alpha}1$ Ameliorates Fatty Liver in Hyperlipidemic Diabetic Rats

Seo, Eun-Hui,Park, Eun-Jin,Joe, Yeon-Soo,Kang, Soo-Jeong,Kim, Mi-Sun,Hong, Sook-Hee,Park, Mi-Kyoung,Kim, Duk-Kyu,Koh, Hyong-Jong,Lee, Hye-Jeong The Korean Society of Pharmacology 2009 The Korean Journal of Physiology & Pharmacology Vol.13 No.6

5'-AMP-activated protein kinase (AMPK) is a heterotrimeric complex consisting of a catalytic ($\alpha$) and two regulatory ($\beta$ and $\gamma$) subunits. Two isoforms are known for catalytic subunit (${\alpha}1$, ${\alpha}2$) and are encoded by different genes. To assess the metabolic effects of $AMPK{\alpha}1$, we examined the effects of overexpression of adenoviral-mediated $AMPK{\alpha}1$ in hyperlipidemic type 2 diabetic rats. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is an established animal model of type 2 diabetes that exhibits chronic and slowly progressive hyperglycemia and hyperlipidemia. Thirty five-week-old overt type 2 diabetic rats (n=10) were administered intravenously with Ad.$AMPK{\alpha}1$. AMPK activity was measured by phosphorylation of acetyl CoA carboxlyase (ACC). To investigate the changes of gene expression related glucose and lipid metabolism, quantitative real-time PCR was performed with liver tissues. Overexpression of $AMPK{\alpha}1$ showed that blood glucose concentration was decreased but that glucose tolerance was not completely recovered on 7th day after treatment. Plasma triglyceride concentration was decreased slightly, and hepatic triglyceride content was markedly reduced by decreasing expression of hepatic lipogenic genes. Overexpression of $AMPK{\alpha}1$ markedly improved hepatic steatosis and it may have effective role for improving hepatic lipid metabolism in hyperlipidemic state.

Impaired insulin signaling upon loss of ovarian function is associated with a reduction of tristetraprolin and an increased stabilization of chemokine in adipose tissue

Choi, Eun-Kyung,Rajasekaran, Monisha,Sul, Ok-Joo,Joe, Yeonsoo,Chung, Hyun-Taeg,Yu, Rina,Choi, Hye-Seon North-Holland 2018 Molecular and cellular endocrinology Vol.461 No.-

<P><B>Abstract</B></P> <P>Loss of ovarian function can activate inflammation and lead to insulin resistance (IR). IR is also a core feature of obesity and obesity-associated metabolic dysfunction. Tristetraprolin/zinc finger protein 36 (TTP) interferes with TNF-α production by destabilizing TNF-α mRNA, and mice deficient in TTP develop a complex syndrome of inflammatory disease (Carballo et al., 1998; Taylor et al., 1999). We hypothesized that ovariectomy (OVX) might also prime inflammation by reducing tristetraprolin/zinc finger protein 36 (TTP) levels. We used a mouse OVX model to study impaired insulin signaling due to loss of ovarian function by evaluating Akt activity upon insulin stimulus. Impaired insulin signaling was initially detected in adipose tissue (AT) at 4 weeks after OVX, and then spread to liver and muscle, finally resulting in systemic IR at 12 weeks after OVX. OVX decreased TTP protein levels and increased adipocyte size, oxidative stress, chemokine expression and fat mass in AT by 4 weeks after surgery. TTP deficiency due to TTP gene deletion induced aberrant insulin signaling and increased chemokine expression and macrophage numbers in AT but did not increase adipocyte size, oxidative stress, or fat mass, suggesting that it promotes insulin signaling by decreasing AT inflammation independent of oxidative stress and adiposity. OVX, like TTP deficiency, increased the stability of chemokine transcripts as assessed from their half-lives. Our data indicate that the impaired insulin signaling resulting from OVX is due to an OVX-induced reduction of TTP and the resulting stabilization of inflammatory chemokines.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A reduction in TTP upon OVX is responsible partly for the impaired insulin signaling induced by OVX in adipose tissue. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Systemic LPS administration induces brain inflammation but not dopaminergic neuronal death in the substantia nigra

정혜경,주일로,Eun-hye Joe 생화학분자생물학회 2010 Experimental and molecular medicine Vol.42 No.12

It has been suggested that brain inflammation is important in aggravation of brain damage and/or that inflammation causes neurodegenerative diseases including Parkinson’s disease (PD). Recently, systemic inflammation has also emerged as a risk factor for PD. In the present study, we evaluated how systemic inflammation induced by intravenous (iv) lipopolysaccharides (LPS) injection affected brain inflammation and neuronal damage in the rat. Interestingly,almost all brain inflammatory responses, including morphological activation of microglia, neutrophil infiltration,and mRNA/protein expression of inflammatory mediators, appeared within 4-8 h, and subsided within 1-3 days, in the substantia nigra (SN), where dopaminergic neurons are located. More importantly, however,dopaminergic neuronal loss was not detectable for up to 8 d after iv LPS injection. Together, these results indicate that acute induction of systemic inflammation causes brain inflammation, but this is not sufficiently toxic to induce neuronal injury.

Overexpression of AMPKՁ1 Ameliorates Fatty Liver in Hyperlipidemic Diabetic Rats

Eunhui Seo,Eun-Jin Park,Yeonsoo Joe,Soojeong Kang,Mi-Sun Kim,Sook-Hee Hong,Mi-Kyoung Park,Duk Kyu Kim,Hyongjong Koh,Hye-Jeong Lee 대한생리학회-대한약리학회 2009 The Korean Journal of Physiology & Pharmacology Vol.13 No.6

5 -AMP-activated protein kinase (AMPK) is a heterotrimeric complex consisting of a catalytic (Ձ) and two regulatory (Ղ and Ճ) subunits. Two isoforms are known for catalytic subunit (Ձ1, Ձ2) and are encoded by different genes. To assess the metabolic effects of AMPKՁ1, we examined the effects of overexpression of adenoviral-mediated AMPKՁ1 in hyperlipidemic type 2 diabetic rats. The Otsuka Long-Evans Tokushima Fatty (OLETF) rat is an established animal model of type 2 diabetes that exhibits chronic and slowly progressive hyperglycemia and hyperlipidemia. Thirty five-week-old overt type 2 diabetic rats (n=10) were administered intravenously with Ad.AMPKՁ1. AMPK activity was measured by phosphorylation of acetyl CoA carboxlyase (ACC). To investigate the changes of gene expression related glucose and lipid metabolism, quantitative real-time PCR was performed with liver tissues. Overexpression of AMPKՁ1 showed that blood glucose concentration was decreased but that glucose tolerance was not completely recovered on 7th day after treatment. Plasma triglyceride concentration was decreased slightly, and hepatic triglyceride content was markedly reduced by decreasing expression of hepatic lipogenic genes. Overexpression of AMPKՁ1 markedly improved hepatic steatosis and it may have effective role for improving hepatic lipid metabolism in hyperlipidemic state.

발아초기 대두씨의 Ascorbate 생합성에 관한 연구

조은혜,주충노 ( Eun Hye Joe,Chung No Joo ) 생화학분자생물학회 1987 BMB Reports Vol.20 No.1

The biosynthetic pathway of ascorbate from glucose was studied at the early phase of germinating soybean seeds (Glycine max). The homogenate of germinating soybean seeds (2nd day) and (U-^(14)C]-glucose were incubated for 3 hours at 37℃ and the several intermediates (galactose, L-galactono γ-lactone, L-gulono γ-lactone, UDP-glucose. D-glucuronate, ascorbate, myo-inositol) were separated by paper chromatography. Radioactivity distribution of the above intermediates indicated that ascorbate was synthesized from glucose predominantly via galactose and L-galactono γ-lactone route rather than L-gulono γ-lactone route. This suggested that glucose is epimerized first to galactose by the UDP-galactose 4-epimerase (EC 5.1.3.2) in this germinating soybean seeds. From the homogenate of germinating soybean seeds (2nd day), UDP-galactose 4-epimerase was purified over 150 folds by MnCl₂ treatment, ammonium sulfate precipitation, Sephadex G-150 gel filtration, Sephadex G-200 gel filtration and finally calcium phosphate gel adsorption. Km values for UDP-glucose and UDP-galactose, optimum pH were determined and the NAD ^+-enzyme was investigated. Km for UDP-glucose and UDP-galactose of UDP-galactose 4-epimerase were 1.1 × 10^(-4) M and 8 × 10^(-5) M respectively. pH optimum was pH 9.0 and NAD+ seemed to be bound to the enzyme relatively strongly. From the above experimental results. it was concluded that the biosynthesis of ascorbate form glucose in germinating soybean seeds seemed to be made predominently via galactose and L-galactono γ-lactone route as other plants.

발아초기 대두씨의 Ascorbate 생합성에 관한 연구

조은혜,주충노,Joe, Eun-Hye,Joo, Chung-No 생화학분자생물학회 1987 한국생화학회지 Vol.20 No.1

[U-$^{14}C$]-glucose를 사용한 발아 초기 대두씨(Glycine max)에서의 ascorbate 합성 중간물질들을 paper chromatography로 분리하여 그 방사능 분포를 조사한 결과 glucose는 galactose로 전환된 후 L-galactono $\gamma$-lactone 중간체를 거쳐 ascorbate 가 되는 것으로 알게되었으며 UDP-galactose 4-epimerase [EC 5.1.3.2] 작용에 의한 glucose의 galactose로의 전환이 확인되었다. UDP-galactose 4-epimerase를 발아 2일째의 대두 추출물로 부터 약 150배 정제한 후 특성을 조사한 결과 UDP-glucose와 UDP-galactose에 대한 Km은 각각 $1.1{\times}10^{-4}M$, $8{\times}10^{-5}M$ 이었고, 적정 pH는 9.0, 보조효소인 $NAD^+$와는 비교적 견고하게 결합되어 있는 것으로 판명되었다. 한편 ascorbate 합성단계의 최종 효소로 알려진 L-galactono $\gamma$-lactone dehydrogenase [EC 1.3.2.3]의 활성을 조사한 결과 L-galactono $\gamma$-lactone에 특이적으로 작용하며 L-gulono $\gamma$-lactone과는 거의 반응하지 않았다. 따라서 대두씨에서의 glucose로 부터의 ascorbate의 합성은 주로 glucose가 ralactose로 전환된 후 L-galactono $\gamma$-lactone을 거쳐 합성되는 것으로 생각된다. The biosynthetic pathway of ascorbate from glucose was studied at the early phase of germinating soybean seeds (Glycine max). The homogenate of germinating soybean seeds (2nd day) and [U-$^{14}C$]-glucose were incubated for 3 hours at $37^{\circ}C$ and the several intermediates (galactose, L-galactono $\gamma$-lactone, L-gulono $\gamma$-lactone, UDP-glucose. D-glucuronate. ascorbate, myo-inositol) were separated by paper chromatography. Radioactivity distribution of the above intermediates indicated that ascorbate was synthesized from glucose predominantly via galactose and L-galactono $\gamma$-lactone route rather than L-gulono $\gamma$-lactone route. This suggested that glucose is epimerized first to galactose by the UDP-galactose 4-epimerase (EC 5.1.3.2) in this germinating soybean seeds. From the homogenate of germinating soybean seeds (2nd day), UDP-galactose 4-epimerase was purified over 150 folds by $MnCl_2$ treatment. ammonium sulfate precipitation, Sephadex G-150 gel filtration, Sephadex G-200 gel filtration and finally calcium phosphate gel adsorption. Km values for UDP-glucose and UDP-galactose, optimum pH were determined and the $NAD^{+}-enzyme$ was investigated. Km for UDP-glucose and UDP-galactose of UDP-galactose 4-epimerase were $1.1{\times}10^{-4}\;M$ and $8{\times}10^{-5}\;M$respectively. pH optimum was pH 9.0 and $NAD^+$ seemed to be bound to the enzyme relatively strongly. From the above experimental results. it was concluded that the biosynthesis of ascorbate form glucose in germinating soybean seeds seemed to be made predominently via galactose and L-galactono $\gamma$-lactone route as other plants.