쥐의 간세포에서의 콜레스테롤 생합성 조절에 대한 3H - desmosterol로 표지된 외부콜레스테롤의 영향

임자혜 ( Ja Hei Ihm ) 생화학분자생물학회 1986 BMB Reports Vol.19 No.1

Effect of exogenous non-esterified cholesterol on the regulation of hepatic cholesterogenesis is investigated using ³H-desmosterol as a metabolic tracer. Using this tracer, the conversion of ³H-desmosterol to ³H-cholesterol by the microsomes can be used to quantitate the transfer of exogenous non-esterified cholesterol to this site, since only the fraction of desmosterol which has reached the microsomes can be converted to cholesterol by the microsomal enzyme, desmosterol reductase. In the present study, the potential use of desmosterol as a tracer for determining metabolic transfer and for estimating the amount of exogenous cholesterol metabolized by the microsomes into bile acids, esterified cholesterol and VLDL is tested. In addition, the reciprocal correlation between HMG-CoA reductase activity and the fluxes of exogenous cholesterol through hepatic microsomes is also presented.

Regulation of Hepatic Cholesterogenesis by Exogenous Cholesterol Investigated with $^3H$-desmosterol Tracer

임자혜,Ihm, Ja-Hei 생화학분자생물학회 1986 한국생화학회지 Vol.19 No.1

쥐의 간세포에서의 콜레스테롤 생합성을 연구하는 데 있어서 외부 콜레스테롤에 대한 방사능 표지로 $^3H$-desmosterol을 사용하였다. 이 $^3H$-desmosterol은 외부 콜레스테롤에 대한 표지로 보통 사용되는 $^{3}H$-콜레스테롤이 갖지 못한 장점을 가지고 있다. 즉, desmosterol은 세포내에서 마이크로솜에만 존재하는 효소인 desmosterol 환원효소에 의해 콜레스테롤로 변환되기 때문에, 이 변환된 값으로부터 외부 콜레스테롤중 마이크로솜에 도달한 콜레스테롤의 양이 얼마인지 예측할 수 있다. 이 논문에서는 $^3H$-desmosterol을 방사능 표지로 이용하여, 외부에 가해진 콜레스테롤 중 마이크로솜에 도달한 양이 얼마인지 계산했으며, 또한 마이크로솜에 도달한 후 에스테르화되거나, VLDL, 또는 담즙산등으로 대사된 외부 콜레스테롤 양도 측정했다. 또한, 외부 콜레스테롤 중 마이크로솜에 도달한 콜레스테롤의 양과 콜레스테롤 생합성의 rate-limiting 효소인 HMG-CoA 환원효소의 활동도와의 관계도 알아 보았다. Effect of exogenous non-esterified cholesterol on the regulation of hepatic cholesterogenesis is investigated using $^3H$-desmosterol as a metabolic tracer. Using this tracer, the conversion of $^3H$-desmosterol to $^3H$-cholesterol by the microsomes can be used to quantitate the transfer of exogenous non-esterified cholesterol to this site, since only the fraction of desmosterol which has reached the microsomes can be converted to cholesterol by the microsomal enzyme, desmosterol reductase. In the present study, the potential use of desmosterol as a tracer for determining metabolic transfer and for estimating the amount of exogenous cholesterol metabolized by the microsomes into bile acids, esterified cholesterol and VLDL is tested. In addition, the reciprocal correlation between HMG-CoA reductase activity and the fluxes of exogenous cholesterol through hepatic microsomes is also presented.

당뇨병유발 백서에서 아미노구아니딘의 지질 과산화에 대한 효과

박성우,임자혜,유형준,임성희,이권엽 대한당뇨병학회 1997 Diabetes and Metabolism Journal Vol.21 No.4

최종당화산물이 혈관평활근세포 증식에 미치는 영향 및 그 기전

송진영,임성희,서지영,조영중,유형준,박성우,임자혜 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.26 No.2

연구배경:혈관평활근세포의 증식은 죽상경화증의 주된 변화로 당뇨병과 동반된 죽상경화증에서도 관찰된다. 최종당화산물(AGE)은 NO와 결합함으로써 이의 혈관평활근세포 증식 억제 작용을 차단한다고 알려져 있으나. 혈관평활근세포에도 최종당솨산물에 대한 수용체가 발견되었음에도 불구하고 최종당화산물이 혈관평활근세포의 증식에 직접 미치는 영향 및 기전에 대하여는 잘 알려져 있지 않다. 본 연구에서는 최종당화산물이 백서 대동맥에서 분리 배양한 혈관평활근세포 증식에 미치는 영향 및 그 기전을 알아 보고자 하였다. 방법:혈관평활근세포는 male Sprague­Dawley 백서의 대동맥에서 분리하여 10% FBS­DMEM 내에서 배양하였고, 세포 증식 실험은 24­well plate에 well당 1×10⁴세포를 0.1% FBS­DMEM(with or without AGE­BSA, anti­AGE antibody, MAP kinase inhibitor, antioxidants)내에서 배양하여 48시간후 MTT assay로 세포 증식을 측정하였다. 결과:AGE­BSA를 2.5, 5.0㎍/mL 농도로 첨가한 경우 혈과평활근세포 수는 AGE­BSA를 가하지 않은 대조군에 비해 1.5, 1.6배 증가되었다. 이러한 AGE­BSA에 의한 혈관평활근세포 증식 촉진 효과는 anti­AGE antibody(100㎍/mL), MAP kinase 억제제인 PD98509(50μM)및 항산화제인 N­acetylcysteine(1μM)이나 butylated hydroxyanisole(10μM)에 의해 차단되었다. 결론:이러한 결과는 AGE가 혈관평활근세포에서 산화 스트레스의 변화를 초래하고 MAP kinase 경로를 통해 혈관평활근세포의 증식 및 죽상경화증의 발생에 기여할 가능성을 뒷받침한다. Background : Diabetes mellitus is an epidemiologically proven risk factor for atherosclerosis. Advanced glycation end products (AGE) have been implicated in the pathogenesis of many diabetic vascular complications. AGE not only change the physicochemical properties of proteins, but also AGE on the vascular smooth muscle cells (VSMCs) have not been fully explained despite of presence of an AGE-receptor on the VSMCs. Methods : In order to test whether AGE promotes atherosclerosis by stimulation of the growth promoting signal transduction pathways in the VSMCs, the proliferation of rat aortic VSMCs cultured in the presence of AGE-BSA with/without anti-AGE antibodies, the MAP kinase inhibitor and antioxidants was measured. The VSMCs (1x10^4 cells in 24-well plates) isolated from the aorta of Sprague-Dawley rats were incubated for 48 hours and the proliferation was assessed by a MTT assay. Results : AGE-BSA increased the proliferation of rat aortic VSMCs by 1.5~1.6 fold at the ㎍/mL level. The stimulatory effect of AGE-BSA (5㎍/mL) was blocked by the anti-AGE antibodies (100 ㎍/mL). PD98059 at 50? inhibited the AGE-BSA-induced VSMC proliferative response of the VSMCs to AGE. AGE-BSA-induced VSMC proliferation was also attenuated by N-acetylcysteine (1?) and butylated hydroxyanisole (10?), implying that increased intracellular oxidative stress might be also involved in the proliferative response to AGE. Conclusion : These results suggest AGE play a role in diabetic atherosclerosis by stimulating of the growth promoting signal transduction pathways in the VSMCs (J Kor Diabetes 26:91~99, 2002).

Session H : Nucleic Acid Biochemistry : HIGHER ORDER STRUCTURE OF 5S rRNA FROM XANTHOMONAS PALARGONII

Bong Rae Cho,Ja Hei Ihm,In Won Park 생화학분자생물학회(구 한국생화학분자생물학회) 1993 추계학술대회집 Vol.- No.-

5S rRNA 의 일차구조에 기초하여 연역한 Pseudomonase 와 Xanthomonas 종들 사이의 계통발생학적 유연관계

조봉래,고문주,임자혜,박인원 ( Bong Rae Cho,Moon Joo Koh,Ja Hei Ihm,In Won Park ) 생화학분자생물학회 1991 BMB Reports Vol.24 No.3

Based on K_(nuc) values calculated from the homology of sequences of thirteen 5S rRNAs from the Pseudomonas and Xanthomonas species, a phylogenic tree was reconstructed using UPGMA method. We have found that K_(nuc) values, rates of nucleotide substitution, are important indices for the evolutionary relationship between the species of Pseudomonas and Xanthomonas. Furthermore, the phylogenic tree reconstructed enables us to suggest that it is reasonable to classify Xanthomonas maltophilia to the genus Xanthomonas instead of Pseudomonas.

염주말에 있어서의 rRNA 유전자들의 배열

정태능,김동수,임자혜,박인원 ( Tae Neung Johng,Dong Soo Kim,Ja Hei Ihm,In Won Park ) 생화학분자생물학회 1992 BMB Reports Vol.25 No.1

Using fragments of appropriate sizes of 5.8S, 17S, and 25S rRNAs as probes, the arrangement of rRNA genes of cytoplasmic rDNA of Chaetomorpha moniligera has been determined, and also the restriction map of the rDNA has been analyzed. The length of the repeating unit of rDNA is approximately 17 kb long and its organization is as follows: (17S rDNA)-ITS 1-(5.8S rDNA)-ITS 2-(25S rDNA). It has been found that 5S rDNA is not present within 17 kb repeating unit. Interestingly, the presence of an intron of about 0.5 kb has been found within the region of 25S rDNA.

Xanthomonas maltophilia의 58 rRNA의 구조 결정

조봉래,고문주,임자혜,박인원,Cho, Bong-Rae,Koh, Moon-Joo,Ihm, Ja-Hei,Park, In-Won 생화학분자생물학회 1991 한국생화학회지 Vol.24 No.1

Xanthomonas maltophilia의 5S rRNA를 분리, 정제하여 효소적 방법과 화학적 방법으로 그 일차구조와 이차구조를 결정하였다. 이 5S rRNA는 119개의 누클레오티드로 구성되어 있으며 변형된 염기를 함유하지 않는다. 그리고 이 5S rRNA는 다른 것들과 달라서 5' 말단에 과외의 우리딘 잔기를 하나 더 가지고 있다. 결정한 X. maltophilia의 5S rRNA의 이차구조는 다른 원핵세포의 것들에 대해서 제안된 일반 모형들(De Wachter 등, 1982 ; Wolters와 Erdmann, 1988 ; 고문주, 1989)과 매우 유사하며, 5개의 이중나선 줄기와 5개의 단일가닥 고리 그리고 2개의 내밀린 구조를 가진다. 66번 위치에 아데노신 잔기를 내밀린 구조로 가지는 대부분의 원핵세포의 5S rRNA들과는 달리, 이 5S rRNA는 이 위치에 우리딘 잔기를 가진다. The primary and secondary structures of the 5S rRNA isolated from Xanthomonas maltophilia were determined by enzymatic and chemical degradation methods. It consists of 119 nucleotides and contains no modified nucleosides. In contrast with other 5S rRNA's, it contains an additional uridine residue on the 5' terminus. The secondary structure of the 5S rRNA from X. maltophilia was very similar to the generalized models proposed by other workers/De Wachter et al., 1982; Wolters and Erdmann, 1988; Koh,1989) The secondary structure of 5S rRNA from X. maltophilia consists of five helices, five loops and two bulges. In contrast with the most of the prokaryotic 5S rRNA's that have adenosine residues at position 66 as a bulge, this 5S rRNA has uridine at this position.

Xanthomonas maltophilia 의 5S rRNA 의 구조 결정

조봉래,고문주,임자혜,박인원 ( Bong Rae Cho,Moon Joo Koh,Ja Hei Ihm,In Won Park ) 생화학분자생물학회 1991 BMB Reports Vol.24 No.1

The primary and secondary structures of the 5S rRNA isolated from Xanthomonas maltophilia were determined by enzymatic and chemical degradation methods. It consists of 119 nucleotides and contains no modified nucleosides. In contrast with other 5S rRNA`s, it contains an additional uridine residue on the 5` terminus. The secondary structure of the 5S rRNA from X. maltophilia was very similar to the generalized models proposed by other workers(De Wachter et al., 1982; Wolters and Erdmann, 1988; Koh, 1989) The secondary structure of 5S rRNA from X. maltophilia consists of five helices, five loops and two bulges. In contrast with the most of the prokaryotic 5S rRNA`s that have adenosine residues at position 66 as a bulge, this 5S rRNA has uridine at this position.