1.Suppressive effects of acetone extract from the stem bark of three Acacia species on nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells
Sowndhararajan KANDHASAMY ; Santhanam RAMESHKUMAR ; Hong SUNGHYUN ; Jhoo JINWOO ; Kim SONGMUN
Asian Pacific Journal of Tropical Biomedicine 2016;6(8):658-664
Objective: To compare the inhibitory effects of acetone extracts from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) on nitric oxide production. Methods: The lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells were used to investigate the regulatory effect of acetone extracts of three Acacia stem barks on nitric oxide production and the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α. Further, the phenolic profile of acetone extracts from the Acacia barks was determined by liquid chromatography-mass spec-trometry/mass spectrometry analysis. Results: All the three extracts significantly decreased LPS-induced NO production as well as the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α in a concentration dependent manner (25, 50 and 75 μg/mL). In the liquid chromatography-mass spectrometry/mass spectrometry analysis, acetone extract of Acacia ferruginea bark revealed the presence of 12 different phenolic components including quercetin, catechin, ellagic acid and rosmanol. However, Acacia dealbata and Acacia leucophloea barks each contained 6 different phenolic components. Conclusions: The acetone extracts of three Acacia species effectively inhibited the NO production in LPS-stimulated RAW 264.7 cells and the presence of different phenolic components in the bark extracts might be responsible for reducing the NO level in cells.
2.Analysis of Postoperative Outcomes in Patients with Intermittent Exotropia According to Preoperative Change of Angle of Deviation
Suji HONG ; Sukgyu HA ; Youngwoo SEO ; Sunghyun KIM
Korean Journal of Ophthalmology 2021;35(2):130-135
Purpose:
The correlation between the existence of the preoperative condition of ≥10 prism diopters (PD) in patients with basic type of intermittent exotropia (IXT) and postoperative outcomes was analyzed.
Methods:
The medical records of patients that underwent surgery for IXT were analyzed retrospectively. The analysis was conducted by dividing the patients into a group with change of <10 PD (group 1) and ≥10 PD (group 2) before the time of the surgery. Patients who received at least 6 months of follow-up after surgery were included. The age, sex, angle of deviation and stereoacuity of the patients were studied. Surgical success was defined as exodeviation of <10 PD or esodeviation of <4 PD at the final visit after the surgery. The correlation between clinical factors and surgical success rate was analyzed by using correlative analysis.
Results:
A total of 129 patients participated in the study. There were 108 (83.7%) and 21 (16.3%) patients in groups 1 and 2, respectively. There were 89 (82.4%) and 17 (80.1%) patients with surgical successes in groups 1 and 2, respectively (p = 0.18). Moreover, 13 (12.0%) patients in group 1 and three (14.3%) patients in group 2 required reoperation, showing no significant difference (p = 0.12). There was no statistically significant correlation between surgical success and preoperative change of angle of deviation <10 PD (odds ratio, 1.78; p = 0.17).
Conclusions
Among the patients with basic type of IXT subjected to the analysis, 16.3% had a change of ≥10 PD before surgery, and there was no significant correlation between surgical success and preoperative change of angle of deviation.
3.Analysis of Postoperative Outcomes in Patients with Intermittent Exotropia According to Preoperative Change of Angle of Deviation
Suji HONG ; Sukgyu HA ; Youngwoo SEO ; Sunghyun KIM
Korean Journal of Ophthalmology 2021;35(2):130-135
Purpose:
The correlation between the existence of the preoperative condition of ≥10 prism diopters (PD) in patients with basic type of intermittent exotropia (IXT) and postoperative outcomes was analyzed.
Methods:
The medical records of patients that underwent surgery for IXT were analyzed retrospectively. The analysis was conducted by dividing the patients into a group with change of <10 PD (group 1) and ≥10 PD (group 2) before the time of the surgery. Patients who received at least 6 months of follow-up after surgery were included. The age, sex, angle of deviation and stereoacuity of the patients were studied. Surgical success was defined as exodeviation of <10 PD or esodeviation of <4 PD at the final visit after the surgery. The correlation between clinical factors and surgical success rate was analyzed by using correlative analysis.
Results:
A total of 129 patients participated in the study. There were 108 (83.7%) and 21 (16.3%) patients in groups 1 and 2, respectively. There were 89 (82.4%) and 17 (80.1%) patients with surgical successes in groups 1 and 2, respectively (p = 0.18). Moreover, 13 (12.0%) patients in group 1 and three (14.3%) patients in group 2 required reoperation, showing no significant difference (p = 0.12). There was no statistically significant correlation between surgical success and preoperative change of angle of deviation <10 PD (odds ratio, 1.78; p = 0.17).
Conclusions
Among the patients with basic type of IXT subjected to the analysis, 16.3% had a change of ≥10 PD before surgery, and there was no significant correlation between surgical success and preoperative change of angle of deviation.
4.A Small Pancreatic Neuroendocrine Tumor with Marked Pancreatic Duct Dilatation and Parenchymal Atrophy.
Sunghyun WON ; Seung Mo HONG ; Myung Hwan KIM ; Sangwoo PARK ; Yunsik CHOI ; Il Young JANG ; Hyoung Jung KIM
Korean Journal of Medicine 2014;86(5):598-602
Pancreatic ductal adenocarcinomas often cause marked pancreatic duct dilatation and associated parenchymal atrophy. We present the case of a small pancreatic neuroendocrine tumor with upstream pancreatic duct dilatation and severe parenchymal atrophy. A small enhancing tumor was observed at the head of the pancreas on computed tomography (CT). Endoscopic ultrasonography-guided fine-needle aspiration was negative for malignancy. We performed a pylorus-preserving pancreatoduodenectomy since we could not exclude the presence of pancreatic ductal adenocarcinoma. The pathological and immunohistochemical examination revealed a serotonin-positive neuroendocrine tumor, measured 1.0 x 0.5 cm. The pathological specimen was remarkable for the marked stromal fibrosis in the area of the tumor, which resulted in narrowing of the main pancreatic duct. Here, we report a rare small pancreatic neuroendocrine tumor, the CT image of which resembled that of pancreatic ductal adenocarcinoma, in which the expression of serotonin and associated fibrosis might be a possible mechanism for the marked main pancreatic duct dilatation.
Adenocarcinoma
;
Atrophy*
;
Biopsy, Fine-Needle
;
Dilatation*
;
Fibrosis
;
Head
;
Neuroendocrine Tumors*
;
Pancreas
;
Pancreatic Ducts*
;
Pancreaticoduodenectomy
;
Serotonin
5.Combinatorial Effect of Mesenchymal Stem Cells and Extracellular Vesicles in a Hydrogel on Cartilage Regeneration
Woong Jin CHO ; Jinsung AHN ; Minju LEE ; Hyejong CHOI ; Sunghyun PARK ; Kyung-Yup CHA ; SunJun LEE ; Yoshie ARAI ; Soo-Hong LEE
Tissue Engineering and Regenerative Medicine 2023;20(1):143-154
BACKGROUND:
Mesenchymal stem cells (MSCs) are used for tissue regeneration due to their wide differentiation capacity and anti-inflammatory effects. Extracellular vesicles (EVs) derived from MSCs are also known for their regenerative effects as they contain nucleic acids, proteins, lipids, and cytokines similar to those of parental cells. There are several studies on the use of MSCs or EVs for tissue regeneration. However, the combinatorial effect of human MSCs (hMSCs) and EVs is not clear. In this study, we investigated the combinatorial effect of hMSCs and EVs on cartilage regeneration via co-encapsulation in a hyaluronic-acid (HA)-based hydrogel.
METHODS:
A methacrylic-acid-based HA hydrogel was prepared to encapsulate hMSCs and EVs in hydrogels. Through in vitro and in vivo analyses, we investigated the chondrogenic potential of the HA hydrogel-encapsulated with hMSCs and EVs.
RESULTS:
Co-encapsulation of hMSCs with EVs in the HA hydrogel increased the chondrogenic differentiation of hMSCs and regeneration of damaged cartilage tissue compared with that of the HA hydrogel loaded with hMSCs only.
CONCLUSION
Co-encapsulation of hMSCs and EVs in the HA hydrogel effectively enhances cartilage tissue regeneration due to the combinatorial therapeutic effect of hMSCs and EVs. Thus, in addition to cartilage tissue regeneration for the treatment of osteoarthritis, this approach would be a useful strategy to improve other types of tissue regeneration.
6. Suppressive effects of acetone extract from the stem bark of three Acacia species on nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells
Kandhasamy SOWNDHARARAJAN ; Songmun KIM ; Rameshkumar SANTHANAM ; Sunghyun HONG ; Jin-Woo JHOO
Asian Pacific Journal of Tropical Biomedicine 2016;6(8):658-664
Objective To compare the inhibitory effects of acetone extracts from the stem bark of three Acacia species (Acacia dealbata, Acacia ferruginea and Acacia leucophloea) on nitric oxide production. Methods The lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells were used to investigate the regulatory effect of acetone extracts of three Acacia stem barks on nitric oxide production and the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α. Further, the phenolic profile of acetone extracts from the Acacia barks was determined by liquid chromatography-mass spectrometry/mass spectrometry analysis. Results All the three extracts significantly decreased LPS-induced NO production as well as the expression of inducible nitric oxide synthase, cyclooxygenase-2 and tumor necrosis factor-α in a concentration dependent manner (25, 50 and 75 μg/mL). In the liquid chromatography-mass spectrometry/mass spectrometry analysis, acetone extract of Acacia ferruginea bark revealed the presence of 12 different phenolic components including quercetin, catechin, ellagic acid and rosmanol. However, Acacia dealbata and Acacia leucophloea barks each contained 6 different phenolic components. Conclusions The acetone extracts of three Acacia species effectively inhibited the NO production in LPS-stimulated RAW 264.7 cells and the presence of different phenolic components in the bark extracts might be responsible for reducing the NO level in cells.
7.Detection of Mitochondrial ATP-Sensitive Potassium Channels in Rat Cardiomyocytes.
Dang Van CUONG ; Nari KIM ; Euiyong KIM ; Youngsuk LEE ; Hyunju KIM ; Sunghyun KANG ; Dae Young HUR ; Hyun JOO ; Young Shik PARK ; Yong Geun HONG ; Sangkyung LEE ; Joonyong CHUNG ; Daehyun SEOG ; Jin HAN
The Korean Journal of Physiology and Pharmacology 2004;8(4):201-206
Mitochondrial ATP-sensitive potassium (mitoKATP) channels play a role in early and late ischemic preconditioning. Nevertheless, the subunit composition of mitoKATP channels remains unclear. In this study, we investigated the subunit composition of mitoKATP channels in mitochondria isolated from rat cardiac myocytes. Mitochondria were visualized using the red fluorescence probe, Mitrotracker Red, while mitoKATP channels were visualized using the green fluorescence probe, glibenclamide-BODIPY. The immunofluorescence confocal microscopy revealed the presence of Kir6.1, Kir6.2 and SUR2 present in the cardiac mitochondria. Western blot analysis was carried to further investigate the nature of mitoKATP channels. For SUR proteins, a 140-kDa immunoreactive band that corresponded to SUR2, but no SUR1 was detected. For Kir6.2, three bands (~4, ~6, and ~0 kDa) were detected, and a specific ~6-kDa immunoreactive band corresponding to Kir6.1 was also observed. These observations suggest that the subunits of mitoKATP channels in rat myocytes include Kir6.1, Kir6.2, and a SUR2-related sulfonylurea-binding protein.
Animals
;
Blotting, Western
;
Fluorescence
;
Fluorescent Antibody Technique
;
Ischemic Preconditioning
;
KATP Channels*
;
Microscopy, Confocal
;
Mitochondria
;
Muscle Cells
;
Myocytes, Cardiac*
;
Potassium
;
Rats*
8.Therapeutic Extracellular Vesicles from Tonsil-Derived Mesenchymal Stem Cells for the Treatment of Retinal Degenerative Disease
Seung Woo CHOI ; Sooin SEO ; Hye Kyoung HONG ; So Jung YOON ; Minah KIM ; Sunghyun MOON ; Joo Yong LEE ; Jaeseung LIM ; Jong Bum LEE ; Se Joon WOO
Tissue Engineering and Regenerative Medicine 2023;20(6):951-964
BACKGROUND:
Retinal degenerative disease (RDD), one of the most common causes of blindness, is predominantly caused by the gradual death of retinal pigment epithelial cells (RPEs) and photoreceptors due to various causes. Cell-based therapies, such as stem cell implantation, have been developed for the treatment of RDD, but potential risks, including teratogenicity and immune reactions, have hampered their clinical application. Stem cell-derived extracellular vesicles (EVs) have recently emerged as a cell-free alternative therapeutic strategy; however, additional invasiveness and low yield of the stem cell extraction process is problematic.
METHODS:
To overcome these limitations, we developed therapeutic EVs for the treatment of RDD which were extracted from tonsil-derived mesenchymal stem cells obtained from human tonsil tissue discarded as medical waste following tonsillectomy (T-MSC EVs). To verify the biocompatibility and cytoprotective effect of T-MSC EVs, we measured cell viability by co-culture with human RPE without or with toxic all-trans-retinal. To elucidate the cytoprotective mechanism of T-MSC EVs, we performed transcriptome sequencing using RNA extracted from RPEs. The in vivo protective effect of T-MSC EVs was evaluated using Pde6b gene knockout rats as an animal model of retinitis pigmentosa.
RESULTS:
T-MSC EVs showed high biocompatibility and the human pigment epithelial cells were significantly protected in the presence of T-MSC EVs from the toxic effect of all-trans-retinal. In addition, T-MSC EVs showed a dosedependent cell death-delaying effect in real-time quantification of cell death. Transcriptome sequencing analysis revealed that the efficient ability of T-MSC EVs to regulate intracellular oxidative stress may be one of the reasons explaining their excellent cytoprotective effect. Additionally, intravitreally injected T-MSC EVs had an inhibitory effect on the destruction of the outer nuclear layer in the Pde6b gene knockout rat.
CONCLUSIONS
Together, the results of this study indicate the preventive and therapeutic effects of T-MSC EVs during the initiation and development of retinal degeneration, which may be a beneficial alternative for the treatment of RDD.