1.Development of High-performance Thin-layer Chromatography (HPTLC) Method for Quality Control of Actinidiae Fructus Vermicultus
Kyung Ho LEE ; Geonha PARK ; Sangjae LEE ; Yung Gyo LEE ; Minsik CHOI ; Roun LEE ; Young Pyo JANG
Natural Product Sciences 2023;29(3):152-161
In this study, we have successfully established a high-performance thin-layer chromatography (HPTLC) method for the quality assessment of Actinidiae Fructus Vermicultus, known as Mokcheonryo(ja) in Korea. This is the dried vermiculate fruit of Actinidia polygama and A. kolomikta, as stipulated by the Korean Herbal Pharmacopoeia (KHP). However, the Korean herbal market often witnesses the inclusion and distribution of ‘Mihudo’, an alternative herbal product sourced from the dried fruits of A. arguta, belonging to the same botanical genus. This confluence has raised substantial apprehensions concerning the veracity of quality. In response to this concern, we have meticulously developed an HPTLC analytical methodology capable of differentiation between Mokcheonryo and Mihudo by exploiting their distinct chemical profiles. We identified umbelliferone as a key marker compound for Mokcheonryo and quantified the content of umbelliferone in each sample using a TLC scanner. Throughout this study, we confirmed distinct fingerprints for Mokcheonryo and Mihudo, providing a reliable means to differentiate between these two herbal medicines. Furthermore, the presence of umbelliferone in Mokcheonryo serves as an indicator compound for quality assessment. The proposed HPTLC method offers a practical and effective tool for ensuring the quality and authenticity of Mokcheonryo in the herbal market.
3.Carbon monoxide prevents TNF-α-induced eNOS downregulation by inhibiting NF-κB-responsive miR-155-5p biogenesis.
Seunghwan CHOI ; Joohwan KIM ; Ji Hee KIM ; Dong Keon LEE ; Wonjin PARK ; Minsik PARK ; Suji KIM ; Jong Yun HWANG ; Moo Ho WON ; Yoon Kyung CHOI ; Sungwoo RYOO ; Kwon Soo HA ; Young Guen KWON ; Young Myeong KIM
Experimental & Molecular Medicine 2017;49(11):e403-
Heme oxygenase-1-derived carbon monoxide prevents inflammatory vascular disorders. To date, there is no clear evidence that HO-1/CO prevents endothelial dysfunction associated with the downregulation of endothelial NO synthesis in human endothelial cells stimulated with TNF-α. Here, we found that the CO-releasing compound CORM-2 prevented TNF-α-mediated decreases in eNOS expression and NO/cGMP production, without affecting eNOS promoter activity, by maintaining the functional activity of the eNOS mRNA 3′-untranslated region. By contrast, CORM-2 inhibited MIR155HG expression and miR-155-5p biogenesis in TNF-α-stimulated endothelial cells, resulting in recovery of the 3′-UTR activity of eNOS mRNA, a target of miR-155-5p. The beneficial effect of CORM-2 was blocked by an NF-κB inhibitor, a miR-155-5p mimic, a HO-1 inhibitor and siRNA against HO-1, indicating that CO rescues TNF-α-induced eNOS downregulation through NF-κB-responsive miR-155-5p expression via HO-1 induction; similar protective effects of ectopic HO-1 expression and bilirubin were observed in endothelial cells treated with TNF-α. Moreover, heme degradation products, except iron and N-acetylcysteine prevented H₂O₂-mediated miR-155-5p biogenesis and eNOS downregulation. These data demonstrate that CO prevents TNF-α-mediated eNOS downregulation by inhibiting redox-sensitive miR-155-5p biogenesis through a positive forward circuit between CO and HO-1 induction. This circuit may play an important preventive role in inflammatory endothelial dysfunction associated with human vascular diseases.
Acetylcysteine
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Bilirubin
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Carbon Monoxide*
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Carbon*
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Down-Regulation*
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Endothelial Cells
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Heme
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Humans
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Iron
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RNA, Messenger
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RNA, Small Interfering
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Vascular Diseases
4.Arg-Leu-Tyr-Glu Suppresses Retinal Endothelial Permeability and Choroidal Neovascularization by Inhibiting the VEGF Receptor 2 Signaling Pathway
Wonjin PARK ; Yi Yong BAEK ; Joohwan KIM ; Dong Hyun JO ; Seunghwan CHOI ; Jin Hyoung KIM ; Taesam KIM ; Suji KIM ; Minsik PARK ; Ji Yoon KIM ; Moo Ho WON ; Kwon Soo HA ; Jeong Hun KIM ; Young Guen KWON ; Young Myeong KIM
Biomolecules & Therapeutics 2019;27(5):474-483
Vascular endothelial growth factor (VEGF) plays a pivotal role in pathologic ocular neovascularization and vascular leakage via activation of VEGF receptor 2 (VEGFR2). This study was undertaken to evaluate the therapeutic mechanisms and effects of the tetrapeptide Arg-Leu-Tyr-Glu (RLYE), a VEGFR2 inhibitor, in the development of vascular permeability and choroidal neovascularization (CNV). In cultured human retinal microvascular endothelial cells (HRMECs), treatment with RLYE blocked VEGF-A-induced phosphorylation of VEGFR2, Akt, ERK, and endothelial nitric oxide synthase (eNOS), leading to suppression of VEGF-A-mediated hyper-production of NO. Treatment with RLYE also inhibited VEGF-A-stimulated angiogenic processes (migration, proliferation, and tube formation) and the hyperpermeability of HRMECs, in addition to attenuating VEGF-A-induced angiogenesis and vascular permeability in mice. The anti-vascular permeability activity of RLYE was correlated with enhanced stability and positioning of the junction proteins VE-cadherin, β-catenin, claudin-5, and ZO-1, critical components of the cortical actin ring structure and retinal endothelial barrier, at the boundary between HRMECs stimulated with VEGF-A. Furthermore, intravitreally injected RLYE bound to retinal microvascular endothelium and inhibited laser-induced CNV in mice. These findings suggest that RLYE has potential as a therapeutic drug for the treatment of CNV by preventing VEGFR2-mediated vascular leakage and angiogenesis.
Actins
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Animals
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Capillary Permeability
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Choroid
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Choroidal Neovascularization
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Claudin-5
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Endothelial Cells
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Endothelium
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Humans
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Macular Degeneration
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Mice
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Nitric Oxide Synthase Type III
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Permeability
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Phosphorylation
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Receptors, Vascular Endothelial Growth Factor
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Retinaldehyde
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Vascular Endothelial Growth Factor A