1.Mitochondrial TFAM as a Signaling Regulator between Cellular Organelles: A Perspective on Metabolic Diseases
Jin-Ho KOH ; Yong-Woon KIM ; Dae-Yun SEO ; Tae-Seo SOHN
Diabetes & Metabolism Journal 2021;45(6):853-865
Tissues actively involved in energy metabolism are more likely to face metabolic challenges from bioenergetic substrates and are susceptible to mitochondrial dysfunction, leading to metabolic diseases. The mitochondria receive signals regarding the metabolic states in cells and transmit them to the nucleus or endoplasmic reticulum (ER) using calcium (Ca2+) for appropriate responses. Overflux of Ca2+ in the mitochondria or dysregulation of the signaling to the nucleus and ER could increase the incidence of metabolic diseases including insulin resistance and type 2 diabetes mellitus. Mitochondrial transcription factor A (Tfam) may regulate Ca2+ flux via changing the mitochondrial membrane potential and signals to other organelles such as the nucleus and ER. Since Tfam is involved in metabolic function in the mitochondria, here, we discuss the contribution of Tfam in coordinating mitochondria-ER activities for Ca2+ flux and describe the mechanisms by which Tfam affects mitochondrial Ca2+ flux in response to metabolic challenges.
2.Electrophysiologic and long-term effects of propafenone on paroxysmal supraventricular tachycardia.
Yun Shik CHOI ; Dae Won SOHN ; Myoung Mook LEE ; Young Bae PARK ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1993;23(3):440-447
BACKGROUND: Propafenone is a new class IC antiarrhythmic drug that has been found to be effective in both supraventricular and ventricular tachyarrhythmias. We studied the electrophysiologic and long-term effects of oral propafenone in the patients with paroxysmal supraventricular tachycardia(PSVT). METHODS: The electrophysiologic study was done in 15 patients with PSVT to assess the short-term efficacy of propafenone 450mg daily. For 10 patients with short-term efficacy, follow up study was done to assess the long-term efficacy of propafenone 450mg daily. RESULTS: The electrophysiologic mechanisms of PSVT were AV nodal reentry in 6 patients and AV reentry in 9 patients. During the electrophysiologic study, propafenone prolonged AH, HV and PR intervals significantly(p<0.05), but did not change the corrected SNRT, SACT, and the ERP of atrium, ventricle, AV node and accessory pathway(AP) significantly. The anterograde and retrograde 1:1 conduction capacity of AV node and AP seemed to decrease. Complete block of anterograde conduction over the AP was noted in 2 of 3 patients with manifest WPW syndrome and complete block of retrograde conduction was noted over the AV node in 1 patient with AV nodal reentry and over the AP in 1 patient with AV reentry. Propafenone was effective in 3 of 6 patients with AVNRT and 7 of 9 patients with AVRT. During long term administration for 3 to 11 months in 10 patients with short-term efficacy of propafenone, 7 patients did not report any episode of symptomatic tachycardia and 3 patients reported less frequent palpitation. There were no side effects during short-and long-term follow up except 2 patients with mild indigestion. CONCLUSIONS: Propafenone seems to be a safe, well tolerated and effective drug for short and long-term therapy of patients with PSVT, especially of orthodromic AV reentry.
Atrioventricular Node
;
Dyspepsia
;
Follow-Up Studies
;
Humans
;
Propafenone*
;
Tachycardia
;
Tachycardia, Supraventricular*
;
Wolff-Parkinson-White Syndrome
3.Clinical Observation on Antihypertensive Effect of Indapamide(Fludex(R)).
Dae Won SOHN ; Byung Hee OH ; Young Bae PARK ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1988;18(3):447-453
The antihypertensive effect of Indapamide(Fludex(R)) was studied in 31 patients of essential hypertension and following results were obtained. 1) Daily dosage was 1mg b.i.d. and total duration of medication was weeks. 2) Mean systolic and diastolic blood pressure declined by 23mmHg(14%) and 18mmHg(17%) respectively. 3) Good or fair controls were achieved in 78% of patients. 4) There was no significant change in heart rate during and after treatment. 5) There were no significant changes in fasting blood sugar, serum creatinine, K+, uric acid, ca++, transaminase and cholesterol levels before and after treatment. 6) In 5 patients transient side effects were observed which resolved spontaneously. In view of these results Indapamide appears to be effective agent for the treatment of mild to moderate hypertension and dose not cause significant change in blood chemistry.
Blood Glucose
;
Blood Pressure
;
Chemistry
;
Cholesterol
;
Creatinine
;
Fasting
;
Heart Rate
;
Humans
;
Hypertension
;
Indapamide
;
Uric Acid
4.Abnormal Left Ventricular Blood Flow Pattern with Apical Involvement in Experimental Myocardial Infarction.
Dae Won SOHN ; Ki Hoon HAN ; Dae Gyun PARK ; Young Seok CHO ; Tae Jin YEUN ; Kyung Kuk HWANG ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1997;27(1):86-93
No abstract available.
Echocardiography
;
Myocardial Infarction*
5.Concurrent treatment with ursolic acid and low-intensity treadmill exercise improves muscle atrophy and related outcomes in rats.
Jae Cheol KIM ; Yun Seok KANG ; Eun Bi NOH ; Baek Woon SEO ; Dae Yun SEO ; Gi Duck PARK ; Sang Hyun KIM
The Korean Journal of Physiology and Pharmacology 2018;22(4):427-436
The objective of this study was to analyze the concurrent treatment effects of ursolic acid (UA) and low-intensity treadmill exercise and to confirm the effectiveness of UA as an exercise mimetic to safely improve muscle atrophy-related diseases using Sprague-Dawley (SD) rats with skeletal muscle atrophy. Significant muscle atrophy was induced in male SD rats through hind limb immobilization using casting for 10 days. The muscle atrophy-induced SD rats were group into four: SED, sedentary; UA, daily intraperitoneal UA injection, 5 mg/kg; EX, low-intensity (10–12 m/min, 0° grade) treadmill exercise; and UEX, daily intraperitoneal UA injection, 5 mg/kg, and low-intensity (10–12 m/min, 0° grade) treadmill exercise. After 8 weeks of treatment, endurance capacity was analyzed using a treadmill, and tissues were extracted for analysis of visceral fat mass, body weight, muscle mass, expression of muscle atrophy- and hypertrophy-related genes, and endurance capacity. Although the effects of body weight gain control, muscle mass increase, and endurance capacity improvement were inadequate in the UA group, significant results were confirmed in the UEX group. The UEX group had significantly reduced body weight and visceral fat, significantly improved mass of tibialis anterior and gastrocnemius muscles, and significantly decreased atrophy-related gene expression of MuRF1 and atrogin-1, but did not have significant change in hypertrophy-related gene expression of Akt and mTOR. The endurance capacity was significantly improved in the EX and UEX groups. These data suggest that concurrent treatment with low-intensity exercise and UA is effective for atrophy-related physical dysfunctions.
Aging
;
Animals
;
Atrophy
;
Body Weight
;
Extremities
;
Gene Expression
;
Humans
;
Immobilization
;
Intra-Abdominal Fat
;
Male
;
Muscle, Skeletal
;
Muscles
;
Muscular Atrophy*
;
Rats*
;
Rats, Sprague-Dawley
6.Value of P Wave in Determining the Site of Accessory Pathway during Orthodromic Atrioventricular Reentry Tachycardia.
Chee Jeong KIM ; Young Dae KIM ; Dong Jin OH ; Byung Hee OH ; Myoung Mook LEE ; Young Bae PARK ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1990;20(1):121-127
The P wave during orthodromic atrioventricular reentry tachycardial were analysed in 19 patients to evaluate the usefulness in identifying the location of accessory pathways. The results were as follows; 1) Definitely inverted and upright P waves in lead I represented the left-sided and right-sided pathways respectively, but the converse is not necessarily true. 2) Dome and Dart appearance in lead VI(4 cases), upright P wave in inferior leads(3 cases), and negative P wave in aVL(3 cases) suggested the left-sided pathway and deeply inverted P waves in inferior leads suggested the posteroseptal or right-sided one. 3) In 17 cases(79%), inverted P wave appeared on more than one lead among the inferior leads, which were helpful to identify the position on P wave and mechanism of supraventricular tachycardia. Although the number of cases especially with right-sided pathway was small to conclude, P wave was useful for determining the location of accessory pathway noninvasively.
Humans
;
Tachycardia*
;
Tachycardia, Supraventricular
7.Classification of the Site of Ventricular Septal Defect with 2-Dimensional Doppler Echocardiography.
Duk Kyung KIM ; Young Dae KIM ; Dong Jin OH ; Chee Jeong KIM ; Myoung Mook LEE ; Young Bae PARK ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1990;20(1):19-28
Seventeen cases of apical hypertrophic cardiomyopthy were reviewed to clarify whether there is any racial difference in phenotypic expression of apical hypertrophic cardiomopathy and to study whether there is any clinical or morphological difference between apical hypertrophic cardiomyopathy of Japanese type (J-APH) and apical hypertrophic cardiomyophthy of non-Japanese type (NJ-APH). The diagnosis was made by cardiac catheterization, left ventriculography and echocardiography. Seventeen patients were divided into 9 (53%) patients with J-APH and 8 (47%) patients with NJ-APH. Mean ages of patients with J-APH and NJ-APH were 55 years and 57 years, respectively. The most common clinical symptoms were chest pain(100%), dyspnea(59%) and palpitation(35%). Mean values of S1+R5 and T wave depth were 58+/-16mm and 16+/-6mm in J-APH and 42+/-11mm and 7+/-3mm in NJ-APH(p<0.05, respectively). Seven patients experienced transient or permanent atrial fibrillation without significant symptoms. Seven patients showed progression or regression of T wave depth greater than 5mm during the period of follow-ups. On echocardiography IVS/LVPW thickness(mm) at the base were 11+/-2/10+/-2 in J-APH and 17+/-7/11+/-2 in NJ-APH, and IVS/LVPW thickness(mm) at the apex were 25+/-7/24+/-5 in J-APH and 26+/-3/26+/-2 in NJ-APH. Three patients with NJ-APH showed asymmetrical septal hypertrophy, cardiac catheterization disclosed elevated left ventricular end diastolic pressure in 11 out of 19 patients. Dye entrapment at the apex during systole was noted in 5 out of 18 patients. In conclusion, our study showed high prevalence rate expression of J-APH in contrast to the Western countries, there may be racial difference in phenotype of apical hypertrophic cardiomyopathy. Considering progression or regression of T-wave depth, NJ-APH may be a forme fruste or regressed form of J-APH.
Asian Continental Ancestry Group
;
Atrial Fibrillation
;
Blood Pressure
;
Cardiac Catheterization
;
Cardiac Catheters
;
Cardiomyopathy, Hypertrophic
;
Classification*
;
Diagnosis
;
Echocardiography
;
Echocardiography, Doppler*
;
Follow-Up Studies
;
Heart Septal Defects, Ventricular*
;
Humans
;
Hypertrophy
;
Phenotype
;
Prevalence
;
Systole
;
Thorax
8.The Effects of Intravenous Adenosine on Reperfusion Injury after Experimental Acute Myocardial Infarction in Open Chest Anesthetized Dogs.
Byung Hee OH ; Duk Kyung KIM ; Dae Won SOHN ; Myoung Mook LEE ; Young Bae PARK ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1994;24(1):105-117
BACKGROUND: Since reperfusion early after acute myocardial infarction has been demonstrated to reduce the infarct size and mortality, many drugs and interventions to reduce the reperfusion injury have been tried with limited success. Adenosine, a potent coronary vasodilator, has been reported to counteract a few mechanisms implicated with reperfusion injury, however, its effects and exact mechanisms to reduce the reperfusion injury have not been clearly elucidated. METHODS AND RESULTS: Effects of adenosine upon infarct size reduction and upon postulated mechanisms involved in the reperfusion injury such as no reflow phenomenon and neutrophil infiltration were evaluated in anesthetized open chest dog model where acute myocardial infarction was induced by 90 minute left anterior descending coronary artery occlusion followed by 240 minute reperfusion. Adenosine(3.75 mg/min) was administered intravenously for total 90 minutes from 30 minutes before reperfusion. Compared to control group(n=6), infarct area/risk area ratio was significantly lower in adenosine group(n=6)(34+12% vs. 22+/-11, p=0.04), although risk area/total left ventricular area ratio were similar in both groups. Myocardial blood flows(MBF), measured by radiolabelled microspheres, of the infarcted regions during coronary occlusion were similar in both groups, however, both subepicardial MBF(0.63+/-0.15ml/min/g vs. 0.95+/-0.31, p=0.02) and subendocardial MBF(0.45+/-0.08 ml/min/g vs. 0.69+/-0.27, p=0.02) were higher in daenosine group. Neutrophil infiltration, semiquantitatively measured under light microscope, were less severe in daenosine group,compared to control group. CONCLUSION: Intravenous adenosine administered before coronary reperfusion appears to reduce infarct size by limiting reperfusion injury through improving no reflow phenomenon and preventing neutrophil infiltration to the ischemic myocardium during reperfusion.
Adenosine*
;
Animals
;
Coronary Occlusion
;
Coronary Vessels
;
Dogs*
;
Microspheres
;
Mortality
;
Myocardial Infarction*
;
Myocardial Reperfusion
;
Myocardium
;
Neutrophil Infiltration
;
No-Reflow Phenomenon
;
Reperfusion Injury*
;
Reperfusion*
;
Thorax*
9.Adjacent Segment Instability after Posterior Lumbar Fusion: Comparison Between Subtotal Laminectomy and Total Laminectomy.
Seong Dae AN ; Tai Hyoung CHO ; Yun Kwan PARK ; Se Hoon KIM ; Jung Yul PARK ; Jung Keun SEO
Korean Journal of Spine 2010;7(3):150-154
OBJECTIVE: Whereas fusion with pedicle screw fixation has shown satisfactory clinical results, solid fusion has been reported to accelerate degenerative changes in adjacent unfused levels. The purpose of this study was to evaluate the effect of bone/ligament/bone integrity after subtotal or total laminectomies on the development of adjacent segment instability (ASI). The hypothesis that total laminectomy would increase ASI more than would subtotal laminectomy was analyzed. Material and METHODS: This is a retrospective study of 316 patients who were treated with posterior fusion and pedicle screw fixation between 1996 and 2001. After attempts to review all 316 patients and radiologic files, 36 patients who were diagnosed with ASI were carefully reviewed, including follow-up periods of 2-8 years. The medical records were carefully reviewed for recurrence of low back pain or neurologic symptoms after a period of postoperative relief, and the radiologic files were evaluated to determine instability. All patients had undergone single-level or multilevel instrumented posterior lumbar interbody fusion for intractable pain related to degenerative conditions of the spine. RESULTS: Patients over the age of 60 were at a higher risk of developing clinical ASI however,fusion length, level and gender were not associated with ASI. The ASI was noted to occur most commonly in the cranial segment prior to fusion. CONCLUSIONS: This study revealed more frequent ASI after total laminectomy than after subtotal laminectomy, especially in elderly patients. The ideal procedure will be one combining maximal canal and foraminal decompressions with minimal resection of bony structures and supporting ligaments.
Aged
;
Follow-Up Studies
;
Humans
;
Laminectomy
;
Ligaments
;
Low Back Pain
;
Medical Records
;
Neurologic Manifestations
;
Pain, Intractable
;
Recurrence
;
Retrospective Studies
;
Spine
10.Exogenous Nitric Oxide-Induced Apoptosis in Cultured Rat Vascular Smooth Muscle Cells.
In Ho CHAE ; Hyo Soo KIM ; Dae Won SOHN ; Byung Hee OH ; Myoung Mook LEE ; Young Bae PARK ; Yun Shik CHOI ; Jung Don SEO ; Young Woo LEE
Korean Circulation Journal 1997;27(11):1199-1210
BACKGROUND: Atherosclerosis is the most important disease that may cause ischemic syndrome in many organs including heart. It is supposed that apoptosis of vascular smooth muscle cells(VSMCs) is closely related to the progression and rupture of atheromatous plaque. Recent studies have documented evidence for elevated level of nitric oxide(NO) within advanced human atheroma and evidence of regression of atheroma by NO. So this study is designed to evaluate whether exogenous NO from NO donors can induce apoptosis of cultured rat VSMCs and which proapoptotic gene(s) is involved in this type of apoptosis. METHODS: Rat VSMCs were cultured and used for experiment at passage 5 through 7. For NO donor, sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine(SNAP) of 0.5, 1, 2, 4mM were exposed to subconfluent VSMCs. The cells were harvested at 6, 12, 24, 48, 72hours after exposure of NO donors. Apoptosis was to be identified by 4, 6-diamidino-2-phenylindole dihydrochloride(DAPI) staining of nuclei and in-situ nick end labeling(TUNEL). The amount of fragmented DNA was analyzed semiquantitatively by diphenylamine(DPA) assay. Immunocytochemical(ICC) staining and western bolt analyses were designed to detect apoptosisrelated gene products, such as Bax-a, Fas and Bcl-2. RESULTS: 1) Decreased mitotic activity was shown after 12 hours exposure of exogenous NO donors, and condensation and margination of chromatin was identified agter 24 hours exposure, by DAPI staining. 2) Percent DNA fragmentation assessed by DPA method was 0,2,9,48,45% at 0,6,12,24,48 hours after exposure of 2mM of NO donors respectively. 3) The expression of Bax-a and Bcl-2 proteins was demonstrated in apoptotic cells by ICC staining. 4) The expression of Bax-a protein in cells under 24 hours exposure of NO donors was elevated by more than 18% of control level on densitometric analysis of western blot. The level of Bcl-2 was suppressed by 26% of control. So, Bax-a/Bcl-2 ratio in cells under exposure of NO donors was elevated to 2.0 from 1.2 of control level. CONCLUSIONS: Exogenous NO from NO donors can induce apoptosis of cultured rat VSMCs, and it is considered that bax-a and bcl-2 genes are involved in this type of apoptosis.
Animals
;
Apoptosis*
;
Atherosclerosis
;
Blotting, Western
;
Chromatin
;
DNA
;
DNA Fragmentation
;
Genes, bcl-2
;
Heart
;
Humans
;
Muscle, Smooth, Vascular*
;
Nitric Oxide
;
Nitroprusside
;
Plaque, Atherosclerotic
;
Rats*
;
Rupture
;
Tissue Donors