1.Development and Validation of an HPLC-DAD Method for Simultaneous Quantitation of Steppogenin and Flavonoids from the Stems of Morus alba
Nguyen Viet PHONG ; You Mie LEE ; Byung Sun MIN ; Jeong Ah KIM
Natural Product Sciences 2024;30(2):65-71
Morus alba L. is well-known for its medicinal and economic value, particularly in Asian countries. Among the isolated compounds from this plant, steppogenin is exhibited as a flavonoid with promising pharmacological properties. This study focused on isolating bioactive compounds, notably steppogenin, from the ethyl acetate extract of M. alba. Additionally, a high-performance liquid chromatography-diode array detector (HPLC-DAD) method for the simultaneous quantification of steppogenin and isolated compounds was developed and validated. The calibration curve showed excellent linearity, with a correlation coefficient (R 2 ) value greater than 0.9957. The limit of detection (LOD) ranged from 0.006 to 0.018 μg/mL, whereas the limit of quantification (LOQ) ranged from 0.020 to 0.061 μg/mL. In precision tests conducted intra-day and inter-day, the accuracy was between 97.32% and 106.39%, with relative standard deviations (RSD) less than 2.27% and 1.65%, respectively. The presence of steppogenin and other flavonoids was confirmed by the study, contributing to the understanding of the chemical composition of M. alba. This validated analytical method offers a reliable means of quantifying steppogenin and aiding future research into its therapeutic potential.
2.Retinal Thickness and Its Interocular Asymmetry Between Parkinson’s Disease and Drug-Induced Parkinsonism
Wool SUH ; Sung Uk BAEK ; Jungsu S. OH ; Seung Yeon SEO ; Jae Seung KIM ; You Mie HAN ; Min Seung KIM ; Suk Yun KANG
Journal of Korean Medical Science 2023;38(11):e86-
Background:
Drug-induced parkinsonism (DIP) is common, but diagnosis is challenging.Although dopamine transporter imaging is useful, the cost and inconvenience are problematic, and an easily accessible screening technique is needed. We aimed to determine whether optical coherence tomography (OCT) findings could differentiate DIP from Parkinson’s disease (PD).
Methods:
We investigated 97 de novo PD patients and 27 DIP patients using OCT and [ 18 F] N-(3-fluoropropyl)-2b-carbon ethoxy-3b-(4-iodophenyl) nortropane (FP-CIT) positron emission tomography. We compared peripapillary retinal nerve fiber layer thickness (pRNFLT) and macular retinal thickness (mRT) between PD and DIP patients as well as interocular differences in the pRNFLT and the mRT. Asymmetric index (%) for retinal thickness (AIRT) was calculated to measure the interocular differences between pRNFLT and mRT. The correlation between AIRT and total striatal specificon-specific binding ratio asymmetry index (SNBRAI) was investigated in PD and DIP patients.
Results:
No significant differences in pRNFLT and mRT values were observed between PD and DIP patients (all Pvalues > 0.090). The mean SNBRAI was significantly higher in PD than in DIP (P = 0.008) patients; however, AIRT did not differ between PD and DIP patients in pRNFLT and mRT (all P values > 0.100). SNBRAI did not correlate with AIRT of pRNFL or mRT in PD and DIP patients (all P values > 0.060).
Conclusion
Our study showed no benefit of retinal thickness and interocular asymmetry measurements using OCT for distinguishing PD from DIP in the early stages. Additional investigations are needed for confirmation.
3.Inhibition of α-Glucosidase by Abietane-Type Diterpenoids Isolated from Roots of Salvia miltiorrhiza
Nguyen Viet PHONG ; Le Thi THANH ; Mi Jeong KWON ; You Mie LEE ; Byung Sun MIN ; Jeong Ah KIM
Natural Product Sciences 2023;29(4):349-356
Salvia miltiorrhiza is a traditional medicinal plant used in Asian medicine for various therapeutic purposes. This plant contains numerous bioactive secondary metabolites, particularly abietane-type diterpenoids. In this study, 16 abietane-type diterpenoids were isolated from S. miltiorrhiza root extracts and structurally identified through advanced spectroscopic techniques. Among them, tanshinone IIA (6) and 15,16-dihydrotanshinone I (11) exhibited potent α-glucosidase inhibition, with IC 50 values of 48.38 ± 0.57 and 48.02 ± 0.47 µM, respectively. Enzyme kinetic studies revealed that these compounds served as non-competitive inhibitors of α-glucosidase. Our findings indicate that natural compounds from S. miltiorrhiza show promise as safe and effective α-glucosidase inhibitors, providing an alternative approach to diabetes treatment. This study contributes to the growing interest in utilizing natural sources for α-glucosidase inhibition and their potential application in healthcare and disease management.
4.Expression of ICAM-1 in Blood Vascular Endothelium and Tissues in Human Premalignant Lesion and Gastric/Hepatocellular Carcinomas
Li KANG ; Moonsik KIM ; You Mie LEE
The Korean Journal of Gastroenterology 2022;79(4):170-176
Background/Aims:
Angiogenesis is essential for the outgrowth and metastasis of tumors. The structure and characteristics of tumor vasculature differ from those of normal vessels. We compared the characteristics of differentially expressed genes in endothelial cells (ECs) isolated from gastric and normal cells.
Methods:
Previously, we had isolated pure tumor ECs (TECs) and normal ECs (NECs) from advanced gastric cancer (AGC) lesions and normal mucosal tissues, respectively. Using the oligomer chip platform of the Affymetrix GeneChip technology, genes that were expressed more than three-fold with a significance of p≤0.001 were measured. The intercellular adhesion molecule 1 (ICAM-1) was found to be overexpressed in the TECs compared to the normal gastric ECs. In this study, the upregulation of ICAM-1 was confirmed in cultured TECs by immunofluorescence.
Results:
The expression of ICAM-1 was upregulated in the ECs, as well as in the stromal and immune cells, in early human gastric preneoplastic and hepatic fibrotic tissues. Upregulation of ICAM-1 was observed in the TECs, immune cells, and cancer epithelial cells in AGC and hepatocellular carcinoma (HCC). These results suggest that increased ICAM-1 expression in the ECs of the tissue microenvironment progressively contributes to the recruitment of immune cells to promote inflammation, leading to fibrosis and tumorigenesis.
Conclusions
Therefore, upregulated ICAM-1 in the tissues in premalignant gastric diseases or hepatic fibrosis and their malignant cancers could be a promising target for disease prevention and treatment.
5.Protective effect of butylated hydroxylanisole against hydrogen peroxide-induced apoptosis in primary cultured mouse hepatocytes.
Geun Hye HWANG ; Yu Jin JEON ; Ho Jae HAN ; Soo Hyun PARK ; Kyoung Min BAEK ; Woochul CHANG ; Joong Sun KIM ; Lark Kyun KIM ; You Mie LEE ; Sangkyu LEE ; Jong Sup BAE ; Jun Goo JEE ; Min Young LEE
Journal of Veterinary Science 2015;16(1):17-23
Butylated hydroxyanisole (BHA) is a synthetic phenolic compound consisting of a mixture of two isomeric organic compounds: 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. We examined the effect of BHA against hydrogen peroxide (H2O2)-induced apoptosis in primary cultured mouse hepatocytes. Cell viability was significantly decreased by H2O2 in a dose-dependent manner. Additionally, H2O2 treatment increased Bax, decreased Bcl-2, and promoted PARP-1 cleavage in a dose-dependent manner. Pretreatment with BHA before exposure to H2O2 significantly attenuated the H2O2-induced decrease of cell viability. H2O2 exposure resulted in an increase of intracellular reactive oxygen species (ROS) generation that was significantly inhibited by pretreatment with BHA or N-acetyl-cysteine (NAC, an ROS scavenger). H2O2-induced decrease of cell viability was also attenuated by pretreatment with BHA and NAC. Furthermore, H2O2-induced increase of Bax, decrease of Bcl-2, and PARP-1 cleavage was also inhibited by BHA. Taken together, results of this investigation demonstrated that BHA protects primary cultured mouse hepatocytes against H2O2-induced apoptosis by inhibiting ROS generation.
Animals
;
Apoptosis/*drug effects
;
Butylated Hydroxyanisole/chemistry/*pharmacology
;
Cell Survival/drug effects
;
Cells, Cultured
;
Hepatocytes/*drug effects
;
Hydrogen Peroxide/*toxicity
;
Male
;
Mice
;
Mice, Inbred ICR
;
Molecular Structure
6.Glycogen Synthase Kinase 3 Inactivation Induces Cell Senescence through Sterol Regulatory Element Binding Protein 1-Mediated Lipogenesis in Chang Cells.
You Mie KIM ; Insun SONG ; Yong Hak SEO ; Gyesoon YOON
Endocrinology and Metabolism 2013;28(4):297-308
BACKGROUND: Enhanced lipogenesis plays a critical role in cell senescence via induction of expression of the mature form of sterol regulatory element binding protein 1 (SREBP1), which contributes to an increase in organellar mass, one of the indicators of senescence. We investigated the molecular mechanisms by which signaling molecules control SREBP1-mediated lipogenesis and senescence. METHODS: We developed cellular models for stress-induced senescence, by exposing Chang cells, which are immortalized human liver cells, to subcytotoxic concentrations (200 microM) of deferoxamine (DFO) and H2O2. RESULTS: In this model of stress-induced cell senescence using DFO and H2O2, the phosphorylation profile of glycogen synthase kinase 3alpha (GSK3alpha) and beta corresponded closely to the expression profile of the mature form of SREBP-1 protein. Inhibition of GSK3 with a subcytotoxic concentration of the selective GSK3 inhibitor SB415286 significantly increased mature SREBP1 expression, as well as lipogenesis and organellar mass. In addition, GSK3 inhibition was sufficient to induce senescence in Chang cells. Suppression of GSK3 expression with siRNAs specific to GSK3alpha and beta also increased mature SREBP1 expression and induced senescence. Finally, blocking lipogenesis with fatty acid synthase inhibitors (cerulenin and C75) and siRNA-mediated silencing of SREBP1 and ATP citrate lyase (ACL) significantly attenuated GSK3 inhibition-induced senescence. CONCLUSION: GSK3 inactivation is an important upstream event that induces SREBP1-mediated lipogenesis and consequent cell senescence.
Aging*
;
Aminophenols
;
ATP Citrate (pro-S)-Lyase
;
Carrier Proteins*
;
Cell Aging
;
Deferoxamine
;
Fatty Acid Synthetase Complex
;
Glycogen Synthase Kinase 3*
;
Glycogen Synthase Kinases*
;
Glycogen Synthase*
;
Glycogen*
;
Humans
;
Lipogenesis*
;
Liver
;
Maleimides
;
Multienzyme Complexes
;
Oxo-Acid-Lyases
;
Phosphorylation
;
RNA, Small Interfering
;
Sterol Regulatory Element Binding Protein 1
7.Glycogen Synthase Kinase 3 Inactivation Induces Cell Senescence through Sterol Regulatory Element Binding Protein 1-Mediated Lipogenesis in Chang Cells.
You Mie KIM ; Insun SONG ; Yong Hak SEO ; Gyesoon YOON
Endocrinology and Metabolism 2013;28(4):297-308
BACKGROUND: Enhanced lipogenesis plays a critical role in cell senescence via induction of expression of the mature form of sterol regulatory element binding protein 1 (SREBP1), which contributes to an increase in organellar mass, one of the indicators of senescence. We investigated the molecular mechanisms by which signaling molecules control SREBP1-mediated lipogenesis and senescence. METHODS: We developed cellular models for stress-induced senescence, by exposing Chang cells, which are immortalized human liver cells, to subcytotoxic concentrations (200 microM) of deferoxamine (DFO) and H2O2. RESULTS: In this model of stress-induced cell senescence using DFO and H2O2, the phosphorylation profile of glycogen synthase kinase 3alpha (GSK3alpha) and beta corresponded closely to the expression profile of the mature form of SREBP-1 protein. Inhibition of GSK3 with a subcytotoxic concentration of the selective GSK3 inhibitor SB415286 significantly increased mature SREBP1 expression, as well as lipogenesis and organellar mass. In addition, GSK3 inhibition was sufficient to induce senescence in Chang cells. Suppression of GSK3 expression with siRNAs specific to GSK3alpha and beta also increased mature SREBP1 expression and induced senescence. Finally, blocking lipogenesis with fatty acid synthase inhibitors (cerulenin and C75) and siRNA-mediated silencing of SREBP1 and ATP citrate lyase (ACL) significantly attenuated GSK3 inhibition-induced senescence. CONCLUSION: GSK3 inactivation is an important upstream event that induces SREBP1-mediated lipogenesis and consequent cell senescence.
Aging*
;
Aminophenols
;
ATP Citrate (pro-S)-Lyase
;
Carrier Proteins*
;
Cell Aging
;
Deferoxamine
;
Fatty Acid Synthetase Complex
;
Glycogen Synthase Kinase 3*
;
Glycogen Synthase Kinases*
;
Glycogen Synthase*
;
Glycogen*
;
Humans
;
Lipogenesis*
;
Liver
;
Maleimides
;
Multienzyme Complexes
;
Oxo-Acid-Lyases
;
Phosphorylation
;
RNA, Small Interfering
;
Sterol Regulatory Element Binding Protein 1
8.Induction of Remission is Difficult due to Frequent Relapse during Tapering Steroids in Korean Patients with Polymyalgia Rheumatica.
Hyoun Ah KIM ; Jisoo LEE ; You Jung HA ; Sang Hyon KIM ; Chan Hee LEE ; Hyo Jin CHOI ; Han Joo BAEK ; Mie Jin LIM ; Won PARK ; Sungiae CHOI ; Yeon Sik HONG ; Yoo Hyun LEE ; Bo Ram KOH ; Chang Hee SUH
Journal of Korean Medical Science 2012;27(1):22-26
Polymyalgia rheumatica is an inflammatory disease affecting elderly and involving the shoulder and pelvic girdles. No epidemiological study of polymyalgia rheumatica was conducted in Korea. We retrospectively evaluated patients with polymyalgia rheumatica followed up at the rheumatology clinics of 10 tertiary hospitals. In total 51 patients, 36 patients (70.6%) were female. Age at disease onset was 67.4 yr. Twenty-three patients (45.1%) developed polymyalgia rheumatica in winter. Shoulder girdle ache was observed in 45 patients (90%) and elevated erythrocyte sedimentation rate (> 40 mm/h) in 49 patients (96.1%). Initial steroid dose was 23.3 mg/d prednisolone equivalent. Time to normal erythrocyte sedimentation rate was 4.1 months. Only 8 patients (15.7%) achieved remission. Among 41 patients followed up, 28 patients (68.3%) had flare at least once. Number of flares was 1.5 +/- 1.6. The frequency of flare was significantly lower in patients with remission (P = 0.02). In Korea, polymyalgia rheumatica commonly develops during winter. Initial response to steroid is fairly good, but the prognosis is not benign because remission is rare with frequent relapse requiring long-term steroid treatment.
Aged
;
Aged, 80 and over
;
Anti-Inflammatory Agents/administration & dosage/*therapeutic use
;
Blood Sedimentation
;
Cohort Studies
;
Female
;
Humans
;
Male
;
Middle Aged
;
Polymyalgia Rheumatica/*drug therapy/epidemiology
;
Prognosis
;
Recurrence
;
Republic of Korea/epidemiology
;
Retrospective Studies
;
Seasons
;
Steroids/administration & dosage/*therapeutic use
9.Usefulness of Stent Implantation for Treatment of Intracranial Atherosclerotic Stenoses.
Kuk Seon KIM ; Dae Hyun HWANG ; Young Hwan KO ; Ik Won KANG ; Eil Seong LEE ; You Mie HAN ; Sun Jung MIN ; In Soo KIM ; Choon Woong HUR ; Shiyi LUI ; Tong LIN ; Tongfu YOU ; Haibin SHI ; Linsun LI
Neurointervention 2012;7(1):27-33
PURPOSE: We evaluated the usefulness of intracranial stent implantation for treating patients with atherosclerotic stenosis and with recurrent, ischemic, neurological symptoms despite having undergone medical therapy. MATERIALS AND METHODS: Between March 2004 and April 2010, we attempted intracranial, stent-assisted angioplasty in 77 patients with 85 lesions (anterior circulation 73 cases, posterior circulation 12 cases) and who had ischemic neurological symptoms with more than 50% major cerebral artery stenosis. We analyzed the results regarding the technical success rate, complication rate, and restenosis rate during the mean 29.4 month follow-up period. RESULTS: Intracranial stent implantation was successfully performed in 74 cases (87.1%). In nine cases among the 11, failed cases, stent implantation failure was due to the tortuosity of the target vessel. One patient experienced middle cerebral artery rupture during the procedure, and we embolized the vessel using a microcoil. Five patients developed cerebral infarction in three weeks after the procedure, three of whom improved using conservative management, although the other, two patients expired. The mean number of residual stenoses decreased from 72.3% to 14.7%. Three patients demonstrated significant in-stent restenosis, i.e. more than 50%, during the follow-up period. CONCLUSION: As stent-assisted angioplasty in intracranial, atherosclerotic stenosis is effective and relatively safe, it can be considered as an alternative treatment for patients with recurrent, ischemic, neurologic symptoms despite having undergone medical therapy.
Angioplasty
;
Cerebral Arteries
;
Cerebral Infarction
;
Constriction, Pathologic
;
Follow-Up Studies
;
Glycosaminoglycans
;
Humans
;
Intracranial Arteriosclerosis
;
Middle Cerebral Artery
;
Neurologic Manifestations
;
Rupture
;
Stents
10.Analysis of Patients with Positive Acid-fast Bacilli Culture and Negative T-SPOT.TB Results.
You Mie HAN ; Hyun Soo KIM ; Cheol Hong KIM ; Hee Jung KANG ; Kyu Man LEE
The Korean Journal of Laboratory Medicine 2010;30(4):414-419
BACKGROUND: T-SPOT.TB is a sensitive test that detects interferon-gamma producing T-cells in tuberculosis patients following stimulation with tuberculosis-specific antigens. Our study was aimed to investigate the possible causes of false negative results of the test by analyzing the patients with positive acid-fast bacilli (AFB) culture and negative T-SPOT.TB results. METHODS: We investigated 138 patients with positive AFB culture results reported between January 2009 and April 2010. Medical records of these patients were reviewed for the results of T-SPOT.TB test, AFB culture, PCR for Mycobacterium tuberculosis (TB-PCR), chest X-ray, drug treatment, etc. Diagnosis of tuberculosis was confirmed by positive TB-PCR or identification of Mycobacterium tuberculosis (MTB). Sensitivity of T-SPOT.TB test was calculated and the possible causes of AFB culture positive and T-SPOT.TB negative results were analyzed. RESULTS: T-SPOT.TB test was performed in 63 of the 138 patients with AFB culture positive results. Fifty-six (88.9%) were positive and 7 patients (11.1%) were negative on T-SPOT.TB test. Of these 7 negative cases, 4 were confirmed as nontuberculous mycobacteria (NTM), 2 were suspected as NTM and diagnosis could not be confirmed in 1. Six of these 7 patients were over 70 yr old and 6 patients had lymphocytopenia. T-SPOT.TB negative results were not observed in any of the 44 patients confirmed to have active tuberculosis (sensitivity 100%). CONCLUSIONS: Our results suggest that T-SPOT.TB test is very sensitive for diagnosing active tuberculosis. NTM may be the main cause of AFB culture positive and T-SPOT.TB negative results, but MTB infection in immunocompromised patients also has to be considered.
Adult
;
Aged
;
Aged, 80 and over
;
Bacillus/*isolation & purification
;
Culture Media
;
Female
;
Humans
;
Lymphocyte Count
;
Lymphopenia/diagnosis/microbiology
;
Male
;
Polymerase Chain Reaction
;
Reagent Kits, Diagnostic
;
Sensitivity and Specificity
;
Tuberculosis/*diagnosis/microbiology/radiography

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