• The Korean Journal of Pharmacology
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• v.21 no.2
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• pp.79-89
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• 1985

Mechanism of calcium transport inhibition of cardiac sarcoplasmic reticulum (SR) by oxygen free radicals was examined. Effects of oxygen free radicals generated by xanthine/xanthine oxidase (X/XO) system on isolated porcine ventricle SR were studied with respect to its calcium binding, lipid peroxidation, SH-group content and alteration of membrane protein components. The results are as follows. 1) Calcium binding of isolated SR was markedly inhibited by X/XO. 2) During the incubation of sarcoplasmic reticulum with xanthine/xanthine oxidase, there were marked inclose in lipid peroxidation and reduction of SH-group content. 3) An antioxidant, p-phenylenediamine effectively prevented the lipid peroxidation but partially prevented the calcium binding inhibition of X/XO treated SR. 4) The reduction of SH-group content of SR treated with X/XO was partially prevented by p-phenylendiamine. 5) When modifying SH-group of SR by treatment with DTNB, the inhibition of calcium binding activity was partially prevented. 6) On gel-permeation chromatography of X/XO-treated sarcoplasmic reticulum, there was an increase of small molecular weight products, probably protein degradation products. 7) Semicarbazide, which prevents the cross-linking reaction of protein components, did not affect the calcium binding inhibition of X/XO-treated SR. From these results, it is suggested that the inhibition of calcium binding of SR by oxygen free radicals results from the consequence of multiple changes of SR components, which are lipid peroxidation, SH-group oxidation and degradation of protein components.

• Environmental Engineering Research
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• v.20 no.2
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• pp.163-169
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• 2015

In this study, we attempted to solubilize protein in slaughter blood (SB) using ultrasonic technology. The application of ultrasonic technology can make enzymatic degradation of SB more effective, which has no comparable alternative for treatment. The SB was homogenized by grinding it for 10 minutes at 10,000 rpm as a pretreatment for preventing its clotting, and then ultrasonic treatment was attempted to solubilize protein in SB. To maximize the efficiency of ultrasonic treatment for SB, the optimum condition of ultrasonic frequency (UF) was determined to be 20 kHz. To optimize the operation conditions of ultrasonification with 20 kHz of frequency, we used response surface methodology (RSM) based on ultrasonic density (UD) and ultrasonification time (UT). The solubilization rate (SR) of protein (%) was calculated to be $101.304-19.4205X_1+0.0398X_2+7.9411X_1{^2}+0.0001X_2{^2}+0.0455X_1X_2$. From the results of the RSM study, the optimum conditions of UD and UT were determined at 0.5 W/mL and 22 minutes, respectively, and SB treated under these conditions was estimated to have a 95% SR. Also, experimentally, a 95.53% SR was observed under same conditions, accurately reflecting the theoretical prediction of 95%.

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.219-226
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• 2005

Sanguisorbae radix (SR) from Sanguisorba officinalis L. (Losaceae) is widely used in Korea and China due to its various pharmacological activity. The present study aims to investigate the effect of the methanol extract of SR on amyloid ${\beta}$ Protein(25-35) $(A{\beta}\;(25-35))$, a synthetic 25-35 amyloid peptide, -induced neurotoxicity using cultured rat cortical neurons. SR, over a concentration range of $10-50\;{\mu}g/ml$, inhibited the $A{\beta}$ (25-35) $(10\;{\mu}M)-induced$ neuronal cell death, as assessed by a 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and the number of apoptotic nuclei, evidenced by Hoechst 33342 staining. Pretreatment of SR $(50\;{\mu}g/ml)$ inhibited $10\;{\mu}M\;A{\beta}$ (25-35)-induced} elevation of cytosolic calcium concentration $([Ca^{2+}]c)$, which was measured by a fluorescent dye, fluo-4 AM. SR $(10\;and\;50\;{\mu}g/ml)$ inhibited glutamate release into medium induced by $10\;{\mu}M\;A{\beta}(25-35)$, which was measured by HPLC, and generation of reactive oxygen species. These results suggest that SR prevents $A{\beta}$ (25-35)-induced neuronal cell damage in vitro.

• The Korean Journal of Physiology and Pharmacology
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• v.3 no.2
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• pp.223-230
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• 1999

Alterations of cardiovascular function associated with various thyroid states have been studied. In hyperthyroidism left ventricular contractility and relaxation velocity were increased, whereas these parameters were decreased in hypothyroidism. The mechanisms for these changes have been suggested to include alterations in the expression and/or activity levels of various proteins; ${\alpha}-myosin$ heavy chain, ${\beta}-myosin$ heavy chain, ${\beta}-receptors,$ the guanine nucleotide-binding regulatory protein, and the sarcolemmal $Ca^{2+}-ATPase.$ All these cellular alterations may be associated with changes in the intracellular $Ca^{2+}$ concentration. The most important regulator of intracellular $Ca^{2+}$ concentration is the sarcoplasmic reticulum (SR), which serves as a $Ca^{2+}$ sink during relaxation and as a $Ca^{2+}$ source during contraction. The $Ca^{2+}-ATPase$ and phospholamban are the most important proteins in the SR membrane for muscle relaxation. The dephosphorylated phospholamban inhibits the SR $Ca^{2+}-ATPase$ through a direct interaction, and phosphorylation of phospholamban relieves the inhibition. In the present study, quantitative changes of $Ca^{2+}-ATPase$ and phospholamban expression and the functional consequences of these changes in various thyroid states were investigated. The effects of thyroid hormones on (1) SR $Ca^{2+}$ uptake, (2) phosphorylation levels of phospholamban, (3) SR $Ca^{2+}-ATPase$ and phospholamban protein levels, (4) phospholamban mRNA levels were examined. Our findings indicate that hyperthyroidism is associated with increases in $Ca^{2+}-ATPase$ and decreases in phospholamban levels whereas opposite changes in these proteins occur in hypothyroidism.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.4
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• pp.377-384
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• 1997

To investigate the properties of ryanodine binding sites of the bird skeletal SR vesicles, SDS PAGE, purification of RyR, and $[^3H]ryanodine$ binding study were carried out in the SR vesicles prepared from the chicken pectoral muscle. The chicken SR vesicles have two high molecular weight (HMW) protein bands as in eel SR vesicles on SDS PAGE. The HMW bands on SDS PAGE were found in the $[^3H]ryanodine$ peak fraction $(Fr_{3-5})$ obtained from the purification step of the ryanodine receptor protein. Bmax and KD of the chicken $[^3H]ryanodine$ binding sites were 12.52 pmol/mg protein and 14.53 nM, respectively. Specific $[^3H]ryanodine$ binding was almost maximal at $50{\sim}100$ ${\mu}M$ $Ca^{2+}$, but was not increased by 5 mM AMP and not inhibited by high $Ca^{2+}$. Binding was significantly inhibited by $20{\sim}100$ ${\mu}M$ ruthenium red and 1 mM tetracaine, but slightly inhibited by $Mg^{2+}$. From the above results, it is suggested that chicken SR vesicles have the ryanodine binding sites to which the binding of ryanodine is almost maximal at $50{\sim}10$ ${\mu}M$ $Ca^{2+}$, is significantly inhibited by ruthenium red and tetracaine, slightly inhibited by $Mg^{2+}$, but not affected by AMP and not inhibited by high $Ca^{2+}$.

• Journal of Radiation Protection and Research
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• v.15 no.2
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• pp.41-49
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• 1990

$^{88}SrCl_2$ was injected to the tail vein of Wistar rats and investigated its distribution and clearance in the tissues and blood. We also measured the changes in Sr binding to the blood plasma protein by administrating chelating agents and organic acids. For the blood, 60% of the Sr occurred in the plasma and 40% on the cell membrane. Fifty percent of Sr in the blood plasma was bound to plasma protein. Sr on the cell membrane seemed to be bound loosely. The binding in the lymphocyte was higher than in the erythrocyte .and granulocyte. Within one hour Sr was quickly disappeared from the blood stream, to be accumulated in the bone. Twenty four hours after the injection, Sr decreased rapidly in the organs of soft tissue, but slowly in the bone. The binding of Sr to plasma protien decreased from 57% of the control to 27-33% in the group treated with chelating agents, EDTA, EGTA and DTPA and to 19% and 40% in the groups treated with organic acids, citrate and oxalate, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3561-3568
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• 2012

The calcium sensing receptor (CaSR) is a member of the largest family of cell surface receptors, the G protein-coupled receptors involved in calcium homeostasis. The role of the CaSR in neoplasia appears to be homeostatic; loss of normal CaSR-induced response to extracellular calcium is observed in cancers of the colon and ovary, while increased release of PTHrP is observed in cancers of the breast, prostate and Leydig cells. Currently CaSR can be considered as a molecule that can either promote or prevent tumor growth depending on the type of cancer. Therefore, recognition of the multifaceted role of CaSR in gliomas and other malignant tumors in general is fundamental to elucidating the mechanisms of tumor progression and the development of novel therapeutic agents. Emphasis should be placed on development of drug-targeting methods to modulate CaSR activity in cancer cells.

• BMB Reports
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• v.30 no.5
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• pp.370-377
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• 1997

A novel assay method is described for rapid quantitation of reaction rate of sterol ${\Delta}^7$-reductase (${\Delta}^7$-SR) which catalyzes reduction of the ${\Delta}^7$-double bond of sterols. Of six different organ tissues-liver, small intestine, brain, lung, kidney, and testis-. ${\Delta}^7$-SR activity was detected only in liver (2.30 nmol/min/mg protein) and testis (0.11 nmol/min/mg protein). Using a newly developed method which employs diet-induced enzyme proteins and ergosterol as substrate, we assessed both kinetics ($K_m=210\;{\mu}M$, $V_{max}=1.93\;nmol/min/mg$) and inhibition of the rat hepatic ${\Delta}^7$-SR against well-studied cholesterol lowering agents such as triparanol ($IC_{50}=16\;{\mu}M$). 3-$\beta$-[2-(diethylamino)ethoxy]androst-5-en-17-one (U18666A) ($IC_{50}=5.2\;{\mu}M$), and trans-1.4-bis(2-chlorobenzylaminomethyl)cyclohexane dihydrochloride (AY-9944) ($IC_{50}=0.25\;{\mu}M$). Of the three well-known AY-9944-sensitive cholesterogenic enzymes (i.e., ${\Delta}^7$-SR, sterol ${\Delta}^8$-isomerase, and sterol ${\Delta}^14$-reductase). ${\Delta}^7$-SR was found to be the most sensitive enzyme with a noncompetitive inhibition of this compound ($K_i=0.109\;{\mu}M$). Substrate specificity studies of the microsomal ${\Delta}^7$-SR indicate that the relative reaction rate for 7-dehydrocholesterol and ergosterol are 5.6-fold and 1.6-fold higher than that for lathosterol. ${\Delta}^7$-SR activity was also modulated by feeding rats a diet supplemented with 0.5% ergosterol (>2.6-fold) in addition to 5.0% cholestyramine plus 0.1% lovastatin ($\simeq$5.0-fold). Finally, microsomal ${\Delta}^7$-SR was solubilized by 1.5% 3-[3-(cholamidopropyl)-dimethylammonio]-1-propanesulfonate (CHAPS) and enriched on PEG (0~10%) precipitation, which should be suitable for further purification of the enzyme.

• The Journal of Korean Obstetrics and Gynecology
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• v.22 no.3
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• pp.117-134
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• 2009

Purpose: In the theory of traditional medicine, Scutellariae Radix (SR) can clear away heat and remove dampness, purge the sthenic fire and remove toxic materials, cool blood and stop bleeding to prevent miscarriage. Recently, SR is known to have anti-cancer activity. For this reason, the present author designed to investigate the effect of SR on proliferation rates of cervical cancer cell line, then effects on genetic profile by SR. Methods: The genetic profile for the effect of SR on human derived cervical cancer cell line, SNU-703, was measured using microarray technique, and the functional analysis on these genes was conducted. Results: Total 519 genes were up-regulated and 606 genes down-regulated in cells treated with SR. Genes induced or suppressed by SR were all mainly concerned with metabolic process, regulation of biological process and protein binding. The network of total protein interactions was measured using cytoscape program, and some key molecules, such as TNFRSF1A, AKT1, MAPK3, and STAT3 that can be used for elucidation of therapeutical mechanism of medicine in future were identified. Conclusion: These results suggest possibility of SR as anti-cancer drug and also suggest that related mechanisms are involved in TNFRSF1A, AKT1, MAPK3, and STAT3 related signalling pathways.

• BMB Reports
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• v.49 no.11
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• pp.612-616
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• 2016

CD44 pre-mRNA includes 20 exons, of which exons 1-5 ($C_1-C_5$) and exons 16-20 ($C_6-C_{10}$) are constant exons, whereas exons 6-15 ($V_1-V_{10}$) are variant exons. $V_6$-exon-containing isoforms have been known to be implicated in tumor cell invasion and metastasis. In the present study, we performed a SR protein screen for CD44 $V_6$ splicing using overexpression and lentivirus-mediated shRNA treatment. Using a CD44 $V_6$ minigene, we demonstrate that increased SRSF3 and SRSF4 expression do not affect $V_6$ splicing, but increased expression of SRSF1, SRSF6 and SRSF9 significantly inhibit $V_6$ splicing. In addition, using a constitutive exon-specific primer set, we could not detect alterations of CD44 splicing after SR protein-targeting shRNA treatment. However, using a $V_6$ specific primer, we identified that reduced SRSF2 expression significantly reduced the $V_6$ isoform, but increased $V_{6-10}$ and $V_{6,8-10}$ isoforms. Our results indicate that SR proteins are important regulatory proteins for CD44 $V_6$ splicing.