사람 洋水의 Adenosine Diphosphoribose Pyrophosphohyrolase

黃炳斗 충남대학교 대학원 1976 論文集 Vol.6 No.-

Adenosine diphosphoribose pyrophosphohydrolase (ADPR-PPase) which catalyzes the hydrolysis at the pyrophosphate linkage of adenosine diphosphoribose (ADP-ribose) has been obtained from human amniotic fluid and partially purified, and it's properties have been investigated. This enzyme shows optimal pH around 9.5 and is heat-labile, being completely inactivated by heat-treatment at 65° for 10 minutes. In contrast to erythrocyte ADPR-PPase of rabbit, the enzyme does not require Mg^(2+), but requires inorganic phosphate for the activity, maximal activity being atained at 20 mM phosphate. The apparent Michaelis constant for ADP-ribose is 1.4 mM. Oxidized and reduced NAD, and pHMB are not inhibitory The enzyme is inhibited markedly by adenine nucleotides which act as a competitive inhibitor, although CMP and GMP are also inhibitory yet lesser in magnitude. These results indicate that the enzyme is controled by related compounds as well as reatcion product.

사람 胎盤組織 膜 結合 Adenosine Deaminase의 性狀에 關한 硏究

황병두,홍승원 충남대학교 의과대학 지역사회의학연구소 1982 충남의대잡지 Vol.9 No.1

The properties of plasma membrane bound adenosine deaminase(ADase) from human placenta have been investigated. The enzyme exhibits a broad pH optimum from pH 6 to 8 and is heat labile, being completely inactivated by heat treatment at 70℃ for 10 minutes. The enzyme is not effected at pH 7 by 2 mM. Li^+, Mg^2+, Ca^2+, Mn^2+, Co^2+, Fe^2+ and Zn^2+, while the enzyme is activated by 2 mM Ca^2+ and Co^2+ at pH 8 and inhibited by 2 mM Cu^2+ independent of pH. The enzyme activity is completely recovered by EDTA (4 mM) only in case of adding Cue+ after preincubation of enzyme with substrate. The apparent Michaelis constant of the enzyme for adenosine is 58 μM. From the above result, it is suggested that the enzyme is different from ADase of soluble fraction of human placenta.

胎盤組織 Cytidine Deaminase에 關한 硏究 (Ⅰ) : Purification & Characterization

황병두,곽상태,임규,이재흔,백문기 충남대학교 의과대학 지역사회의학연구소 1984 충남의대잡지 Vol.11 No.2

Cytidine deaminase has been partially purified from human term placenta approximately 26-fold by combination of ammoninm sulfate saturation, sephacryl S-300, DEAE-cellulose and hydroxyapatite chromatography, and then its properties have been investigated. The enzyme shows a broad optimum pH from 5 to 9 and is heat-stable being, almost remained its activity by heat treatment at 70℃ for 8 minutes. The enzyme activity is inhibited to 23% and 77% by 2 mM of Cu^2+ and Co^2+, respectively, but, other cations do not affect the enzyme activity. The apparant Michaelis constant for cytidine and deoxycytidine are 74 uM and 69 uM, respectively. Kinetic analysis of cytidine deminase in presence of 0.25 mM Cu^2+ shows that the nature of the inhibition to cytidine deaminase is competitive, considering that Vmax is independent while km value is increased. The enzyme activity is completely inhibited by 0. 5 mM of p-hydroxymecuribenzoicacid(PHMB)but all of the activity is recovered in adding mercaptoethanol. The enzyme activity is decreased about 50% in prescence of 5 mM of polyamines. The enzyme activity is mainly located in the nuclei (80%) and cytosol(16%) fractions. he molecular weight of the enzyme is about 770, 000.

初期 胎盤組織의 Adenosine Deaminase

황병두,변해공,임규,이재흔,백문기 충남대학교 의과대학 지역사회의학연구소 1983 충남의대잡지 Vol.10 No.2

Two forms of adenosine deaminase (ADase) having molecular weights of 1,500,000 & 800,000 in the soluble fraction of the early placenta and plasma membrane bound ADase of the placenta were demonstrated respectively. Their properties and activity changes with gestational age have been investigated. ADases exhibit a broad pH optimum from 6 to 9 and heat labile, being completely inactivated by heat treatment at 70℃ for 10 min. Soluble fraction ADases and plasma membrane bound ADase are inhibited about 100% and 80% by s mM Cu^2+. The apparent Michaelis constant of pADase-cytotrophoblast(pADase-C) for adenosine is 110μM, and for deoxyadenosine 21μM, that of pADase-syncytiotrophoblast(pADase-S) is 80μM and 35μM, and that of plasma membrane bound ADase is 31μM and 26μM, respectively. Kinetic analysis of pADase-C and pADase-S in the presence of 10μM Cu^2+ show that the nature of the inhibition to pADase-C and pADase-S are noncompetitive and uncompetitive, respectively. The pADases (pADase-C + pADase-S) activity decreased with gestational age, the activity at term being about one-tenth that of the early placenta, while plasma membrane bound ADase increased with gestational age by about 2-fold. From above results it is discussed that pADase-C is related to cytotrophoblast, pADase-S to syncytiotrophoblast and plasma membrane bound ADase to cellular differentiation of placenta, and suggested that soluble fraction ADases of human placenta is different from plasma membrane bound ADase in their biological roles.

胎盤組織 S-Adenosyl-L-Methionine : Protein-Carboxyl-O-Methyltransferase에 關한 硏究 Protein-Carboxyl-O-Methyltransferase from Human Placenta

黃炳斗,白汶基 충남대학교 의과대학 지역사회의학연구소 1983 충남의대잡지 Vol.10 No.2

S-Adenosy-L-methionine: protein-carboxyl O-methyltransferase (protein methylase Ⅱ) has been purified from human term placenta approximately 8,700-fold with a 14% yield. the enzyme shows a sharp pH optimum around pH 5.8. The enzyme is easily inactivated by heat treatment for 5 minutes at 60℃, and when stored at -20℃ even in the presence of 10% glycerol, approximately 70% of activity has been lost in 8 weeks. Copper ion (Cu^2+) is a potent inhibitor, the activity being completely inhibited at 2 mM and 86% of the activity is recovered by addition of 4mM EDTA. The other divalent cations are almost without effect. Human chorionic gonadotropin, immunoglobulin A, and histone ⅡA are good substrates for this enzyme with preference for HCG. The Km value for S-adenosyl-L-methionine and Ki value for S-adenosyl-L-homocysteine are 2.08 × 10 exp (-6) M and 5.8 × 10 exp (-7) M, respectively. The methylated membrane protein from human placenta are analyzed by dodecyl sulfatepolyacrylamide gel electrophoresis. The bands 9 and 17 of the membrane protein are identified as two major classes of methyl acceptors, but in the presence of epinephrine, methylation of the band 9 is decreased and the bands 13, 14, 16 and 17 become major methyl-acceptors. Especially methylation of the band 17 is increased about 3-fold compared with that of the band 17 in the absence of epinephrine. The nuclear membrane proteins are found to be a good methyl-acceptor protein. The enzyme activity with nuclear fraction as substrate is increased about 17% when 39,000 x g supernatant and prednisolone are added together to reaction mixture. Methylated histone prefers to bind methylated nucleus rather than nonmethylated nucleus. The enzyme activity is changed with gestational age, the activity at first and second trimester being about 2 times higher than that of term placenta. From the above results, the possible roles of this enzyme, such as a regulation of hormone action, transport of histone and steroid hormone into the nucleus and signal transmission, are discussed.

胎盤 組織의 Protein Methylase II

황병두,이재흔,백문기 충남대학교 의과대학 지역사회의학연구소 1982 충남의대잡지 Vol.9 No.2

Protein methylase Ⅱ has been purified from human term placenta approximately 8,760 folds with a 14.5% yield. The enzyme shows sharp pH optimum around pH 5.8. The enzyme is easily inactivated by heat treatment for 5 minutes at 60℃, and when stored at -20℃ even in the presence of 10% glycerol, approximately 70% of activity has been lost for 8 weeks The enzyme doesn't require any divalent cations and Cu^2+ is a potent inhibitor, the activity being completely inhibited at 2 mM and 86% of the activity is recovered by addition of 4 mM EDTA. Histone IIA and myelin. basic protein arc good substrate for this enzyme. Km for S-adenosyl-L-methicnine and Ki for S-adenosyl-L-homocysteine are 2.03 x 10 exp(-6) M and 5. 8 x 10 exp(-7) M respectively. The methylated membrane protein from human placenta were analyzed by dodecyl sulfate/polyacrylamide gel electrophoresis. Band 1, 2, 4, 15, 17 are identified as 5 major classes of methyl-acceptor protein for protein methylase Ⅱ. The role of placental membrane prctein methylation is discussed with regard to placental function.

사람 洋水의 Adenosine Diphosphoribose Pyrophosphohydrolase

黃炳斗,白汶基 충남대학교 의과대학 지역사회의학연구소 1975 충남의대잡지 Vol.2 No.2

Adenosine diphosphoribose pyrophosphohydrolase (ADPR-PPase) which catalyzes the hydrolysis at the pyrophosphate linkage of adenosine diphosphoribose (ADP-ribose) formed from nicotinamide adenine dinucleotide (NAD) by NAD nucleosidase has been partially purified from human amniotic fluid, and its properties have been investigated. This enzyme shows optimal pH around 9.5 and is heat-labile, being completely inactivated by heat treament at 65˚ for 10 minutes. In contrast to erythrocyte ADPR-PPase of rabbit, the enzyme does not require Mg^2+, but requires inoragnic phosphate for the activity, maximal activity being attained at 20mM phosphate. The apparent Michaelis constant for ADP-ribose is 1.4 mM. The enzyme is inhibited markedly by adenine nucleotides which act as a competitive inhibitor, although CMP and GMP are also inhibitory, yet lesser in magnitude, whereas oxidized and reduced NAD and pHMB are not inhibitory. These results indicate that the enzyme is controled by related compounds as well as reaction product.

胎盤組織의 Adenosine Deaminase

황병두,이재흔,백문기 충남대학교 의과대학 지역사회의학연구소 1981 충남의대잡지 Vol.8 No.2

Adenosine deaminase(ADase) has been partially purified approximately 800-fold from human placenta, and its properties have been investigated. The enzyme exhibits a broad pH optimum from pH 6 to 8 and is heat-labile, being completely inactivated by heat treatment at 70℃ for 10 minutes. In contrast to other tissue ADase, the enzyme is inhibited by 2mM of Cu^2+ and Fe^2+ at pH 7, and by 2 mM of Cu^2+, Fe^2+, Co^2+ and Mn^2+ at pH 8. The inhibitory effect of Cu^2+ on the enzyme is so strong that the enzyme is completely inactivated by 20 μM of Cu^2+. The enzyme activity is easily recovered by EDTA(4 mM) in case of adding Cu^2+ after preincubation of enzyme with substrate, while the recovery is about 50% by treating Cu^2+ prior to addition of substrate. Thus substrate binding to enzyme seems to prohibit the Cu^2+ from binding to the enzyme. The apparant Michaelis constant for adenosine is 77μM, and the kinetic analysis in the presence of 2 μM Cu^2+ shows that Km is independent while Vmax is decreased. The molecular weight of the enzyme is about 800,000 and the apparant activity of the other type of ADase is not detected. From the above results it is suggested that the enzyme is different from other tissue ADase in its nature of protein and possibly biologic role.

6-Hydroxydopamine이 Sabstance P의 昇壓作用에 미치는 影響

黃炳斗 충남대학교 의과대학 지역사회의학연구소 1983 충남의대잡지 Vol.10 No.1

In this study we investigated whether the effects of intracranioventricular substance P involve central catecholaminergic system. Intracranioventricular substance P (10 ng/㎏) increased blood pressure but heart rate was changed variably. The central pressor responseof substance P is markedly attenuated by intracranioventricular pretreatment with 6-hydroxydopamine (500 ㎍/㎏). From the above results, it is suggested that the central pressor response of substance P involve central catecholaminergic system.

Peanut Sprout Extracts Cultivated with Fermented Sawdust Medium Inhibits Benign Prostatic Hyperplasia In Vitro and In Vivo

송준휘,황병두,정현주,문보경,김진욱,고기성,김배환,김원룡,김운재,명순철,문성권 대한남성과학회 2020 The World Journal of Men's Health Vol.38 No.3

Purpose: In this study, we tested whether the resveratrol-enriched peanut sprout extracts cultivated with fermented sawdust medium (PSEFS) could suppress benign prostatic hyperplasia (BPH) in vitro and in vivo. Materials and Methods: The mode of action of PSEFS was estimated by employing high-performance liquid chromatography analysis, MTT assay, cell counting, cell cycle analysis, immunoblots, and immunoprecipitation and electrophoretic mobility shift assay. In vivo efficacy of PSEFS was analyzed in BPH animal model via immunostaining and enzyme-linked immunosorbent assay. Results: We selected the Yesan peanut sprout variety, which contains the highest level of resveratrol. The resveratrol levels in PSEFS were higher than those obtained with hydroponic technology. PSEFS treatment induced cell cycle arrest at the G1- phase by downregulating CDK4 and cyclin D1 via p21WAF1 induction in the RWPE-1 and WPMY prostate cells, thereby decreasing their proliferation. Treatment with PSEFS decreased ERK1/2 phosphorylation and increased JNK phosphorylation. The levels of DNA-bound transcription factors associated with proliferation (nuclear factor-κB, Sp-1, and AP-1) decreased upon PSEFS treatment in both prostate cells. Additionally, the levels of the molecular markers of BPH development (5α-reductase, androgen receptor, fibroblast growth factor, Bcl-2, and Bax) also changed by the addition of PSEFS. Finally, in a testosterone propionate-induced BPH model in rats, PSEFS administration attenuated the size, weight, and thickness of prostate tissues with no signs of death. Conclusions: These results showed that PSEFS inhibited BPH both in vitro and in vivo and might be useful in the development of a potential BPH therapy.