1.Stress Accelerates Depressive-Like Behaviors through Increase of Notch2 Expression in N141I Mutation Presenilin-2 Transgenic Mice
Seung Sik YOO ; Sun Mi GU ; Kyung Tak NAM ; Jeong Soon CHOI ; Yong Sun LEE ; In Jun YEO ; Ji Eun YU ; Sanghyeon KIM ; Dong Won LEE ; Hyeon Joo HAM ; Ju Young CHANG ; Jaesuk YUN ; Dong Ju SON ; Sang-Bae HAN ; Jin Tae HONG
Biomolecules & Therapeutics 2026;34(3):544-555
Alzheimer’s disease (AD) is characterized by progressive cognitive deterioration and significant depression. However, the mechanisms linking depression to AD pathology remain unclear. Here, we investigated whether Notch2 signaling mediates depressionlike behaviors in presenilin-2 (PS2) N141I mutant mice, an early-onset AD model. PS2 wild-type (WT) and mutant (MT) mice aged 12-15 months were subjected to unpredictable chronic mild stress (UCMS) for 4 weeks, followed by sucrose preference, tail-hanging, and forced swimming tests. Behavioral assessments showed that UCMS exacerbated anhedonia and immobility only in PS2 MT mice. Molecular analysis revealed concomitant increases in plasma corticosterone, hippocampal γ-secretase activity, and Notch2 expression, and elevated total and phosphorylated glucocorticoid receptor levels in PS2 MT-UCMS mice. Gene expression profiling of human hippocampal datasets confirmed upregulation of NOTCH2 in Alzheimer’s disease and depression.Pharmacological inhibition of γ-secretase and Notch signaling with DAPT normalizes depressive behavior, reduces corticosterone release, attenuates GR phosphorylation, and inhibits Notch2 signaling in PS2 MT mice. These findings identify Notch2 as a pivotal mediator linking chronic stress to molecular changes associated with depression and AD, and suggest that targeting Notch2 signaling may provide therapeutic benefits for comorbid mood and neurodegenerative disorders.
2.Unexpected Cancellation of Radioactive Iodine Treatment after Thyroid Hormone Withdrawal: Lessons from a Case Series
Hye-Seon OH ; Won Gu KIM ; Won Bae KIM ; Jin-Sook RYU ; Min Ji JEON ; Tae Yong KIM
Endocrinology and Metabolism 2026;41(2):300-307
Background:
Radioactive iodine treatment (RAIT) is an essential therapy for differentiated thyroid cancer. However, unforeseen complications arising during thyroid hormone withdrawal (THW) can lead to Cancellation of the scheduled treatment. This study aimed to identify cases in which THW-RAIT was discontinued due to THW-related complications and to explore potentially preventable causes to improve patient management.
Methods:
Among 4,174 patients who underwent THW-RAIT between 2012 and 2024, 39 did not complete the planned treatment. After excluding Cancellations unrelated to THW, 11 (0.26%) patients with unexpected THW-related medical issues were analyzed.
Results:
The median age of the included patients was 61 years (range, 23 to 70), and 10 were male. The reasons for THW-RAIT Cancellation were hyponatremia (n=1), abnormal liver function (n=1), renal dysfunction (n=3), and combined liver and renal dysfunction (n=6). The patient with hyponatremia was taking a thiazide diuretic. Most cases of liver dysfunction were associated with prior use of herbal medications, whereas renal dysfunction was linked to diuretic or nonsteroidal anti-inflammatory drug use, pre-existing conditions such as single kidney or diabetic nephropathy, or inadequate oral intake during low-iodine preparation. Two cases of concurrent liver and renal dysfunction were attributed to rhabdomyolysis following intense exercise or heavy physical labor.
Conclusion
Enhanced patient education, comprehensive pre-treatment assessment, and careful avoidance of high-risk medications are essential to prevent THW-related complications and minimize disruptions in RAIT.
3.Exercise improves muscle mitochondrial dysfunction-associated lipid profile under circadian rhythm disturbance
Yu GU ; Dong-Hun SEONG ; Wenduo LIU ; Zilin WANG ; Yong Whi JEONG ; Jae-Cheol KIM ; Dae Ryong KANG ; Rose Ji Eun LEE ; Jin-Ho KOH ; Sang Hyun KIM
The Korean Journal of Physiology and Pharmacology 2024;28(6):515-526
We investigated whether endurance exercise training (EXT) ameliorates circadian rhythm (CR)-induced risk factors by improving skeletal muscle (SKM) mitochondrial biogenesis, reducing oxidative stress, and modulating apoptotic protein expression. We distinguished between regular and shift workers using the National Health and Nutrition Examination Survey (NHANES) and investigated the health problems caused by shift work (CR disturbance) and the potential therapeutic effects of exercise. In our animal study, 36 rats underwent 12 weeks of CR disturbance, divided into regular and irregular CR groups. These groups were further split into EXT (n = 12) and sedentary (n = 12) for an additional 8 weeks. We analyzed SKM tissue to understand the molecular changes induced by CR and EXT. NHANES data were analyzed using SAS 9.4 and Prism 8 software, while experimental animal data were analyzed using Prism 8 software. The statistical procedures used in each experiment are indicated in the figure legends. Our studies showed that CR disturbance increases dyslipidemia, alters circadian clock proteins (BMAL1, PER2), raises apoptotic protein levels, and reduces mitochondrial biogenesis in SKM. EXT improved LDL-C and HDLC levels without affecting muscle BMAL1 expression. It also enhanced mitochondrial biogenesis (AMPK, PGC-1α, Tfam, NADH-UO, COX-I), antioxidant levels (Catalase, SOD1, SOD2), and apoptotic protein (p53, Bax/Bcl2) expression or activity in SKM. We demonstrated that shift work-induced CR disturbance leads to dyslipidemia, diminished mitochondrial biogenesis, and reduced antioxidant capacity in SKM. However, EXT can counteract dyslipidemia under CR disturbance, potentially lowering the risk of cardiovascular disorders.
4.Effects of Short-term Repeated Sprint Exercise Training and Moderate Intensity Continuous Exercise Training on Vascular Function in Healthy Young Adults
Hye Rim HONG ; Ye Ji CHOI ; Tae Gu CHOI ; Jae Yeop KIM ; Yun Wook KIM ; Yong Joon JUNG ; Min Jeong CHO ; Hyun Jeong KIM ; Sae Young JAE
The Korean Journal of Sports Medicine 2024;42(2):136-144
Purpose:
Moderate-intensity continuous training (MICT) improves exercise capacity with vascular benefits, but time constraints hinder consistent adherence. High-intensity interval training (HIIT) has emerged as a time-efficient alternative, with repeated sprint training (RST) being the shortest format. We hypothesized that RST would be as effective as MICT in improving vascular function and exercise capacity in young adults.
Methods:
Twenty-three adults (mean age, 26.2±3.8 years) were randomly assigned to either RST or MICT. RST involved 20 sets of 4-second cycling sprints followed by 30-second active recovery, totaling 11 minutes. MICT consisted of 30-minute cycling at 50% to 60% of heart rate reserve. Vascular function evaluated via brachial artery flow-mediated dilation. Exercise capacity (maximum oxygen uptake, total exercise load test time) and anaerobic capacity (maximum power, anaerobic threshold) were measured using maximum exercise tests. These variables were measured befre and after a 6-week training.
Results:
Both groups showed comparable improvements in flow-mediated dilation (p< 0.05). Maximum oxygen intake slightly improved, while total exercise time significantly increased for both (p< 0.05). Anaerobic threshold unchanged, while maximum power improved (p< 0.05).
Conclusion
These findings underscore that RST is a time-efficient exercise strategy, which improves vascular function and exercise capacity as effectively as MICT in young adults.
5.Effects of Isometric Handgrip Exercise on Carotid Arterial Function and Cardiovascular Vasoreactivity Response to Sympathetic Stress in Young Adults
Yun Wook KIM ; Joon Youp SEONG ; Ho Jeong MIN ; Tae Gu CHOI ; Yong Joon JUNG ; Min Jeong CHO ; Hyun Jeong KIM ; Sae Young JAE
The Korean Journal of Sports Medicine 2024;42(1):38-45
Purpose:
Isometric handgrip exercise (IHE) has a favorable cardiovascular effect and improves hemodynamic responses. Whether IHE attenuates stress-related hemodynamic reactivity assessed during a sympathetic challenge remains unexplored. We tested the hypothesis that an acute bout of IHE would improve carotid arterial function and attenuate cardiovascular vasoreactivity response to sympathetic stress in healthy adults.
Methods:
In a randomized cross-over design, sixteen healthy adults (aged 21.8±3.1 years) were enrolled. Participants completed two testing sessions, separated by 1 week. Trials were either a control trial or performed IHE for two sets of 2 minutes at 30% of maximal voluntary contraction for each hand. The participant’s hand was immersed in an ice water bath (4 ℃ ) up to the wrist for 2 minutes. Carotid artery diameter, β-stiffness index, and compliance using ultrasound machine and brachial blood pressure (BP), heart rate (HR) were measured as indices of vasoreactivity at baseline, during, and recovery from cold pressor testing (CPT).
Results:
The BP, HR, carotid artery diameter, and β-stiffness index increased similarly during CPT in both trials (p< 0.001), without any interaction effect. Compared with the IHE trial, arterial compliance decreased in the control groups at 120 seconds during recovery with a significant interaction effect (p=0.02).
Conclusion
These findings suggest that an acute IHE did not attenuate BP, HR, carotid artery diameter and β-stiffness index vasoreactivity, but improved carotid artery compliance to sympathetic activation in healthy young adults.
6.Correlation Analysis between Hypogonadal Symptoms and Changes in Body Composition and Physical Fitness after Testosterone Treatment in Men with Testosterone Deficiency
Tae Yong PARK ; Moon Young CHOI ; Dong Soo KIM ; Jeong Kyun YEO ; Mahadevan RAJASEKARAN ; Min Gu PARK
The World Journal of Men's Health 2024;42(1):178-187
Purpose:
This study analyzed changes in body composition and physical fitness in men with testosterone deficiency (TD) after testosterone treatment (TT) and examined the correlations of body composition and physical fitness with serum testosterone levels and hypogonadal symptoms.
Materials and Methods:
Seventy patients with TD were divided into control (group I, n=23) and experimental (group II, n=47) groups. Patients in the experimental group were administered intramuscular testosterone enanthate (250 mg) for six months. The aging males symptom scale (AMS) score, international prostate symptom score (IPSS), body mass index, waist circumference, and serum laboratory values were measured at baseline and at the end of the study. Bioelectrical impedance analysis was used to assess the patients’ body composition. Seven types of basic exercise tests were used to evaluate the patients’ physical fitness.
Results:
After six months, there were no significant differences in group I, while group II had significantly improved IPSS and AMS scores; increased hemoglobin, hematocrit, prostate-specific antigen, and testosterone levels and skeletal muscle mass; and waist circumference, and body fat mass. All elements of the physical fitness test were significantly improved in group II, with the exceptions of flexibility and endurance. Decreased waist circumference was correlated with changes in testosterone levels in group II, and the IPSS, cardiorespiratory fitness, and agility were correlated with improved hypogonadal symptoms.
Conclusions
TT improved the hypogonadal and lower urinary tract symptoms in patients with TD and improved body composition, physical fitness, and metabolic syndrome parameters. Increased testosterone and improved hypogonadal symptoms were correlated with a decrease in waist circumference and an improvement in cardiorespiratory fitness and agility. As such, when implementing TT, we should consider whether these areas may be improved, as this can help to predict the effect.
7.Effect of Gelatin Content on Degradation Behavior of PLLA/ Gelatin Hybrid Membranes
Yunyoung JANG ; Juwoong JANG ; Bae-Yeon KIM ; Yo-Seung SONG ; Deuk Yong LEE
Tissue Engineering and Regenerative Medicine 2024;21(4):557-569
BACKGROUND:
Poly(L-lactic acid) (PLLA) is a biodegradable polymer (BP) that replaces conventional petroleumbased polymers. The hydrophobicity of biodegradable PLLA periodontal barrier membrane in wet state can be solved by alloying it with natural polymers. Alloying PLLA with gelatin imparts wet mechanical properties, hydrophilicity, shrinkage, degradability and biocompatibility to the polymeric matrix.
METHODS:
To investigate membrane performance in the wet state, PLLA/gelatin membranes were synthesized by varying the gelatin concentration from 0 to 80 wt%. The membrane was prepared by electrospinning.
RESULTS:
At the macroscopic scale, PLLA containing gelatin can tune the wet mechanical properties, hydrophilicity, water uptake capacity (WUC), degradability and biocompatibility of PLLA/gelatin membranes. As the gelatin content increased from 0 to 80 wt%, the dry tensile strength of the membranes increased from 6.4 to 38.9 MPa and the dry strain at break decreased from 1.7 to 0.19. PLLA/gelatin membranes with a gelatin content exceeding 40% showed excellent biocompatibility and hydrophilicity. However, dimensional change (37.5% after 7 days of soaking), poor tensile stress in wet state (3.48 MPa) and rapid degradation rate (73.7%) were observed. The highest WUC, hydrophilicity, porosity, suitable mechanical properties and biocompatibility were observed for the PLLA/40% gelatin membrane.
CONCLUSION
PLLA/gelatin membranes with gelatin content less than 40% are suitable as barrier membranes for absorbable periodontal tissue regeneration due to their tunable wet mechanical properties, degradability, biocompatibility and lack of dimensional changes.
8.Innovative use of a commercial product (Biomagic) for odor reduction, harmful bacteria inhibition, and immune enhancement in pig farm
Abdul Wahab AKRAM ; Hae-Yeon CHO ; Evelyn SABA ; Ga-Yeong LEE ; Seung-Chun PARK ; Sung Dae KIM ; Yong Gu HAN ; Man Hee RHEE
Korean Journal of Veterinary Research 2024;64(4):e32-
The global increase in livestock production has correspondingly intensified farm odors due to harmful bacteria, reduced immunity, and disease progression. In this study, we treated feces with Biomagic-Enzyme complex for 4 months to understand the relationship between farm odor, immunity against common viral diseases, immune cytokines, and changes in the microbiota. A gas meter (MultiRAE) was used to measure ammonia (NH3) and hydrogen sulfide (H2S) while odor intensity and offensiveness were characterized by the non-objective scaling method. A complete blood count was performed and plasma was obtained after blood centrifugation at 3,000 rpm for 20 minutes. The cytokine profile was evaluated using commercial kits. Microbial DNA was extracted and purified from fecal samples to analyze the microbiota. Microbial DNA and viral RNA/DNA were obtained from fecal samples and amplified to determine the expression of transmissible gastroenteritis virus (TGEV), porcine reproductive and respiratory syndrome (PRRS), and porcine circovirus type 2 (PCV2). Our results indicated that Biomagic reduced odor nuisance by decreasing ammonia levels, resulting in faint and fairly offensive odor intensity. After the enzyme treatment, Escherichia coli populations significantly reduced across all 3 farms. In contrast, beneficial Lactobacillus spp. levels remained stable, indicating the enzyme selectively targeted harmful bacteria while preserving beneficial ones. The beneficial Lachnospiraceae, Spirochaetaceae, and Bacteroidaceae were found to be higher in the third month of treatment. TGEV was not detected, while PRRS and non-pathogenic PCV2 showed a positive infection rate. In conclusion, Biomagic reduced ammonia, prevented viral infection from pig farms, and improved gut-beneficial bacteria and microbiota.
9.Observation of neutrophil extracellular traps in the development of diabetic nephropathy using diabetic murine models
You Hyun JEON ; Se-Hyun OH ; Soo-Jung JUNG ; Eun-Joo OH ; Jeong-Hoon LIM ; Hee-Yeon JUNG ; Ji-Young CHOI ; Sun-Hee PARK ; Chan-Duck KIM ; Yong-Lim KIM ; Chang-Won HONG ; Jang-Hee CHO
Laboratory Animal Research 2024;40(4):424-434
Background:
Diabetic nephropathy (DN) is a progressive complication among patients with diabetes and the most common cause of end-stage kidney disease. Neutrophil extracellular traps (NETs) are known to play a role in kidney disease, thus this study aimed to determine their role in the development of diabetic kidney disease using diabetic murine models.
Results:
Protein and histological analyses revealed that db/db mice and streptozotocin DN models expressed no significant NET-related proteins, myeloperoxidase, citrullinated histone H3 (citH3), neutrophil elastase, and lymphocyte antigen 6 complex locus G6D (Ly6G). However, the inflamed individuals in the DN model showed that citH3 and Ly6G were highly deposited in the renal system based on immunohistochemistry images. In vitro, NET treatment did not induce apoptosis in glomerular endothelial and renal tubular epithelial cells. NET inhibition by DNase administration demonstrated no significant changes in cell apoptosis.
Conclusions
NET-related proteins were only expressed in the DN model with tubulointerstitial inflammation. Our study revealed that NETs are only induced in mice with hyperglycemia-induced inflammation.
10.Exercise improves muscle mitochondrial dysfunction-associated lipid profile under circadian rhythm disturbance
Yu GU ; Dong-Hun SEONG ; Wenduo LIU ; Zilin WANG ; Yong Whi JEONG ; Jae-Cheol KIM ; Dae Ryong KANG ; Rose Ji Eun LEE ; Jin-Ho KOH ; Sang Hyun KIM
The Korean Journal of Physiology and Pharmacology 2024;28(6):515-526
We investigated whether endurance exercise training (EXT) ameliorates circadian rhythm (CR)-induced risk factors by improving skeletal muscle (SKM) mitochondrial biogenesis, reducing oxidative stress, and modulating apoptotic protein expression. We distinguished between regular and shift workers using the National Health and Nutrition Examination Survey (NHANES) and investigated the health problems caused by shift work (CR disturbance) and the potential therapeutic effects of exercise. In our animal study, 36 rats underwent 12 weeks of CR disturbance, divided into regular and irregular CR groups. These groups were further split into EXT (n = 12) and sedentary (n = 12) for an additional 8 weeks. We analyzed SKM tissue to understand the molecular changes induced by CR and EXT. NHANES data were analyzed using SAS 9.4 and Prism 8 software, while experimental animal data were analyzed using Prism 8 software. The statistical procedures used in each experiment are indicated in the figure legends. Our studies showed that CR disturbance increases dyslipidemia, alters circadian clock proteins (BMAL1, PER2), raises apoptotic protein levels, and reduces mitochondrial biogenesis in SKM. EXT improved LDL-C and HDLC levels without affecting muscle BMAL1 expression. It also enhanced mitochondrial biogenesis (AMPK, PGC-1α, Tfam, NADH-UO, COX-I), antioxidant levels (Catalase, SOD1, SOD2), and apoptotic protein (p53, Bax/Bcl2) expression or activity in SKM. We demonstrated that shift work-induced CR disturbance leads to dyslipidemia, diminished mitochondrial biogenesis, and reduced antioxidant capacity in SKM. However, EXT can counteract dyslipidemia under CR disturbance, potentially lowering the risk of cardiovascular disorders.

Result Analysis
Print
Save
E-mail