• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.526-534
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• 2013

This study was conducted to examine the effects of Opuntia ficus-indica complex (OF) on the lipid metabolism, bile acid in feces, alanine aminotransferase (ALT) activity, aspatate aminotransferase (AST) activity, composition of urine and expression of cholesterol related mRNA in streptozotocin (STZ)-induced diabetic rats. Thirty two male Sprague-Dawley rats were randomly divided into non-diabetic control (NC), diabetic control (DC), diabetic OF of 2% (OF-2) and diabetic OF of 5% (OF-5), then each group was fed for 3 weeks. Plasma total cholesterol, non-esterified fatty acids (NEFA), total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL) were decreased significantly (p<0.05) in OF-5 group compared to DC, but high density lipoprotein (HDL) was not changed. AST and ALT were also reduced and bile acid excretion was improved. Composition of urine in OF-5 was almost same in NC. The expression of cholesterol $7{\alpha}$-hydroxylase (CYP7A1), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMG-CoA-R), Low density lipoprotein receptor (LDL-R) mRNA indicated that feeding OF have the effects of cholesterol decreation in plasma by synthesis of bile acid from cholesterol. These results provide experimental evidence about improved lipid metabolism of the OF feeding in the STZ-induced diabetic rats.

• YAKHAK HOEJI
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• v.57 no.6
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• pp.388-393
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• 2013

Previously, we have reported that lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, increased melanin synthesis through intracellular $Ca^{2+}$ release in B16 cells. In this study we investigated the possible involvement of nitric oxide (NO) in the mechanism of lovastatin-induced melanogenesis. Lovastatin elevated NO formation in a dose-dependent manner. Treatment with mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), precursors of cholesterol, did not significantly alter the lovastatin-induced NO production, suggesting that inhibition of cholesterol metabolism may not be involved in the mechanism of this action of lovastatin. Both NO formation and melanogenesis induced by lovastatin was significantly suppressed by treatment with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylinidazoline-1-oxyl-3-oxide (cPTIO), an inhibitor of NO synthase and a NO scavenger, respectively. The lovastatin-induced NO production was significantly affected not by EGTA, an extracellular $Ca^{2+}$ chelator, but by an intracellular $Ca^{2+}$ chelator (BAPTA/AM) and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8). Taken together, these results suggest that lovastatin may induce melanogenesis through NO formation mediated by intracellular $Ca^{2+}$ release in B16 cells. These results further suggest that lovastatin may be a good candidate for the therapeutic application of various hypopigmentation disorders.

• Korean Journal of Clinical Pharmacy
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• v.30 no.1
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• pp.31-35
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• 2020

Objective: The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are frequently prescribed medications worldwide for the treatment of hypercholesterolemia. Statins are considered to be well tolerated; however, they have a potential for myotoxicity. Concomitant drugs that inhibit cytochrome P450 3A4 can increase the concentration of statins and thus the risk of developing myotoxicity. The purpose of this study was to evaluate risk factors associated with potential drug-drug interactions in patients receiving statins. Methods: The subjects of this study were patients aged more than 18 years who received at least one prescription of statins in a general hospital located in Chuncheon-si, Korea, between January 1, 2018, and March 31, 2018. Data regarding statin use and baseline characteristics was collected from the computerized hospital database. Logistic regression analysis was used to identify risk factors associated with potential drug-drug interactions. Results: A total of 1061 patients were finally included in the study. The incidence of potential drug-drug interactions was 45% in all subjects. According to the results of the multivariate logistic regression analysis, myocardial infarction as the indication of statin, arrhythmia or heart failure as a comorbidity, and aspartate aminotransferase levels higher than 40 IU/L were significant risk factors for potential drug-drug interactions in study subjects. Diltiazem was the most commonly co-prescribed drug that caused potential drug-drug interactions with statins. Conclusion: There was a considerable rate of potential drug-drug interactions in patients receiving statins. Health care professionals should attempt to reduce potential drug-drug interactions during statin administration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.826-833
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• 2002

This study was conducted to investigate the effects of YK-209 mulberry leaves on HMG-CoA reductase activity and lipid composition of liver in streptozotocin-induced diabetic rats. Sprague-Dawley male rats weighing 100 $\pm$ 10 B were randomly assigned as a normal group and four STZ-induced diabetic groups according to the level of dietary mulberry leaves supplement. The experimental diets were fed ad libidum, so that diabetes was experimentally induced by intravenous injection of STZ 55 mg/kg of body weight after feeding for 3 weeks. Animals were sacrificed on the 9th day of diabetic states. The levels of serum triglyceride, total-cholesterol and LDL-cholesterol in DM group were higher than mulberry leaves supplemented groups and normal group, but those of the mulberry leaves supplemented groups were significantly decreased to normal level. In contrast, the leavels of serum HDL-cholesterol in DM group was significantly reduced than that of normal group, but mulberry leaves supplemented groups were increased to normal level. Atherogenic index in DM group was higher about 3 fold than the normal group but the DM-0.1Y and DM-0.2Y groups were maintained the normal level. Contents of total lipid and triglyceride of liver in DM group were significantly lower than that of normal group, but the mulberry Leaves supplemented groups increased than that of DM group. The contents of hepatic cholesterol in DM group was 160% higher than that of normal group, but the mulberry leaves supplementation groups maintained the normal level. The activity of hepatic 3-hydroxy -3-methylglutaryl Coenzyme A (HMG-CoA) reductase in DM group was 43% lower than that of normal group, but had no significant difference between DM-0.1Y, DM-0.2Y and normal groups. In conclusion, YK-209 mulberry loaves has improving effect of the lipid metabolism in STZ-induced diabetic rats through hepatic HMG-CoA reductase activity, and the change of lipids contents in serum and liver.

• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.13-18
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• 2003

In experiment 1, rats (n＝6) fed diet containing 10 g/kg cholesterol for 4 wk (control) with either no amaranth (control), amaranth grain (300 g/kg, AG) or amaranth oil (90 g/kg, AO). Both the AG and AO groups had lower concentration of serum and hepatic cholesterol and triglyceride than the controls (p < 0.05). Fecal excretions of cholesterol and bile acid in AO group increased about 4 fold and 2 fold, respectively, while AG affected only bile acid excretion (p < 0.05). In experiment 2, rats (n＝6) were fed the cholesterol diet for 4 wk and injected intraperitoneally with saline (control) or amaranth squalene (AS) for 7d. The hypolipidemic effect of AS was evident in both serum and liver. Fecal excretions of cholesterol and bile acid were greater (p < 0.05) in AS than control. HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase activity was reduced in AS group (11.6%, p=0.13). This study suggests that the cholesterol-lowering effect of AS is mediated by greater fecal elimination of steroids through interference with cholesterol absorption.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.107-112
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• 1998

Lovastatin is a lipid lowering agent for the treatment of hypercholesterolemia and belongs to a new class of pharmacologic compounds called the 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors. By competitively inhibiting HMG CoA reductase, lovastatin disrupts the biosynthesis of cholesterol in hepatic and peripheral cells and increases the synthesis of high-density-lipoprotein HDL) receptors. Following oral administration, the lactone ring of lovastatin is hydrolysed to the active inhibitor of HMG CoA reductase, lovastatin acid. Lovastatin is known to have poor oral absorption and wide individual variation. In this study, bioequivalence test of two lovastatin formulations, the test drug ($Lovaload^{TM}$, Chong Kun Dang Pharmaceutical Co.) and the reference drug ($Mevacor^{TM}$, Chung Wae Pharmaceutical Co.) were conducted according to the guidelines of Korea Food and Drug Administration (KFDA). A total of 18 healthy male volunteers, $31.90\pm3.60$ years old and $72.17\;7.88$ kg of body weight in average, were evaluated in a randomized crossover manner with a 2-week washout period. Concentrations of lovastatin acid in plasma were measured upto 12 hours following a single oral administration of eight tablets (20 mg of lovastatin per tablet) by high-performance liquid chromatography with UV detection at 238 nm. The area under the concentration-vs-time curve from 0 to 12 hours $(AUC_{0-12h})$ was calculated by the trapezoidal summation method. The statistical analysis showed that there are no significant differences in $AUC_{0-12h),\;C_{max}\;and\;T_{max}$ between the two formulations ($6.72\%,\;1.52\%,\;and\;0.88\$, respectively). The least significant differences between the formulations at $\alpha$=0.05 were less than $20\%\;(11.65\%,\;19.73\%,\;and\;14.81\%\;for\;AUC_{0-12h},\;C_{max}\;and\;T_{max}$, respectively). The $90\%$ confidence intervals for these parameters were also within $\pm20\%\;(-1.50{\leq}{\delta}{\leq}15.00$, $-12.50{\leq}{\delta}{\leq}15.50,\;and\;-9.64{\leq}{\delta]{\leq}11.40{\leq}\;for\;\;AUC_{0-12h}$ ,$C_{max}\;and\;T_{max}$, respectively). In conclusion, the new generic product $Lovaload^{TM}$ was proven to be bioequivalent with the reference drug.

• Journal of Pharmaceutical Investigation
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• v.41 no.4
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• pp.239-247
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• 2011

Simvastatin is an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, which catalyzes the conversion of HMG-CoA to mevalonate, an early and rate-limiting step in the biosynthesis of cholesterol. Simvastatin has good permeability, but it also has low solubility (BCS class II), which reduces its bioavailability. To overcome this problem, a solid dispersion is formed using a spray-dryer with polymeric material carrier to potentially enhance the dissolution rate and extend drug absorption. As carriers for solid dispersion, Gelucire$^{(R)}$44/14 and Gelucire$^{(R)}$ 50/13 are semisolid excipients that greatly improve the bioavailability of poorly-soluble drugs. To avoid any toxic effects of an organic solvent, we used aqueous medium to melt Tween$^{(R)}$ 80 and distilled water. The structural behaviors of the raw materials and the solid dispersion were analyzed by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The DSC and PXRD data indicated that the crystalline structure of simvastatin was transformed to an amorphous structure through solid dispersion. Then, solid dispersion-based tablets containing 20 mg simvastatin were prepared with excipients. Dissolution tests were performed in distilled water and artificial intestinal fluid using the USP paddle II method. Compared with that of the commercial tablet (Zocor$^{(R)}$ 20 mg), the release of simvastatin from solid dispersion based-tablet was more efficient. Although the stability study is not complete, this solid dispersion system is expected to deliver poorly water-soluble drugs with enhanced bioavailability and less toxicity.

• Development and Reproduction
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• v.11 no.2
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• pp.59-66
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• 2007

Understanding molecular mechanisms that control embryonic stem cell (ESC) self-renewal and differentiation is important for the development of ESC-based therapies. Statins, inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase), potently reduce cholesterol level. As well as inhibiting cholesterol synthesis, statins inhibit other intermediates in the mevalonate pathway such as farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), major substrates for protein isoprenylation. Studies showed that pleiotropic effects of statins beyond cholesterol lowering property arise from inhibition of protein isoprenylation that is involved in various cellular functions including proliferation and differentiation. It has been determined that statins have inhibitory effect on ESC self-renewal and stimulatory effect on ESC differentiation into adipogenic/osteogenic lineages. Importantly, statins mediate downregulation of ESC self-renewal by inhibiting RhoA-dependent signaling, independently of their choresterol-lowering properties. Understanding statin's actions on ESCs may provide important insights into the molecular mechanisms that regulate self-renewal or differentiation of ESCs.

• Journal of Life Science
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• v.26 no.4
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• pp.398-405
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• 2016

Statins, the inhibitors of 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase, are widely used in treatments of hypercholesterolemia and newly known as anti-cancer effect of various cancer cells. Recently, several studies suggested that reactive oxygen species (ROS) play a critical role on cell death signaling. However, mechanism of ROS by rosuvastatin is currently unclear. This study aimed to explore the molecular mechanism of apoptosis by rosuvastatin in human prostate cancer PC-3 cells. Cell viability and apoptosis-related protein expression were measured by MTT assay and western blotting, respectively. In addition, the levels of apoptosis and ROS were analyzed. The results showed that rosuvastatin dramatically reduced cell viability in a dose- and time-dependent manner. We confirmed that rosuvastatin induced apoptosis through reduction of procaspase-3 and cleavage of poly (ADP-ribose) polymerase (PARP) in PC-3 cells. In addition, rosuvastatin stimulated ROS production in a dose-dependent manner and pre-treatment with N-acetylcysteine (NAC), a ROS scavenger, significantly recovered rosuvastatin-induced ROS and apoptosis. Thus, we concluded that rosuvastain induces apoptosis through generation of ROS in human prostate cancer PC-3 cells and provides a promising approach to improve the efficacy of cancer therapy.

• The Journal of Internal Korean Medicine
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• v.29 no.2
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• pp.432-442
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• 2008

Objective : Ssanggang-tang(SGT) is noted as an effective method to treat hyperlipidemia in China. The main purpose of this study was analysis of the effects of Ssanggang-tang(SGT) on rats induced with caused hyperlipidemia. Methods : We observed 3 experimental groups: normal, control, and SGT. Rats were provided a normal diet in the normal group, and the other groups were provided a hyperlipidemic diet to induce hyperlipidemia. After 2 weeks, SGT was treated in the SGT group. For 6 weeks, values related to hyperlipidemia were observed in the 3 experimental groups. Results : SGT decreased some values related to hyperlipidemia like total cholesterol, low density lipoprotein cholesterol(LDL cholesterol), triglyceride, acetocoenzyme A acetyltransferase(ACAT), and 3-hydroxy-3-methylglutaryl coenzyme A reductase(HMG-CoA reductase). However, it showed no effect on weight change or high density lipoprotein cholesterol(HDL cholesterol). Conclusion : These results suggest that SGT might be effective in treatment and prevention of hyperlipidemia.