Methanol extract of Myelophycus caespitosus ameliorates oxidative stress‑induced cytotoxicity in C2C12 murine myoblasts via activation of heme oxygenase-1

Cheol Park,Hyun Hwangbo,Han Min Ho,Jin-Woo Jeong,조승목,김기영,황혜진,Yung Hyun Choi 한국수산과학회 2023 Fisheries and Aquatic Sciences Vol.26 No.1

Myelophycus caespitosus, a brown alga belonging to genus Myelophycus, has been traditionally used as a food and medicinal resource in Northeastern Asia. However, few studies have been conducted on its pharmacological activity. In this study, we evaluated whether methanol extract of M. caespitosus (MEMC) could protect against oxidative damage caused by hydrogen peroxide (H2O2) in C2C12 murine myoblasts. Our results revealed that MEMC could suppress H2O2-induced growth inhibition and DNA damage while blocking the production of reactive oxygen species. In H2O2-treated cells, cell cycle progression was halted at the G2/M phase, accompanied by changes in expression of key cell cycle regulators. However, these effects were attenuated by MEMC. In addition, we found that MEMC protected cells from induction of apoptosis associated with mitochondrial impairment caused by H2O2 treatment. Furthermore, MEMC enhanced the phosphorylation of nuclear factor-erythroid-2 related factor 2 (Nrf2) and expression and activity of heme oxygenase-1 (HO-1) in H2O2-treaetd C2C12 myoblasts. However, such anti-apoptotic and cytoprotective effects of MEMC were greatly abolished by HO-1 inhibitor, suggesting that MEMC could increase Nrf2-mediated activity of HO-1 to protect C2C12 myoblasts from oxidative stress.

Morin exerts cytoprotective effects against oxidative stress in C2C12 myoblasts via the upregulation of Nrf2-dependent HO-1 expression and the activation of the ERK pathway

Lee, Moon Hee,Han, Min Ho,Lee, Dae-Sung,Park, Cheol,Hong, Su-Hyun,Kim, Gi-Young,Hong, Sang Hoon,Song, Kyoung Seob,Choi, Il-Whan,Cha, Hee-Jae,Choi, Yung Hyun UNKNOWN 2017 INTERNATIONAL JOURNAL OF MOLECULAR MEDICINE Vol.39 No.2

<P>In the present study, we investigated the cytoprotective efficacy of morin, a natural flavonoid, against oxidative stress and elucidated the underlying mechanisms in C2C12 myoblasts. Our results indicated that morin treatment prior to hydrogen peroxide (H2O2) exposure significantly increased cell viability and prevented the generation of reactive oxygen species. H2O2-induced comet-like DNA formation and gamma H2AX phosphorylation were also markedly suppressed by morin with a parallel inhibition of apoptosis in C2C12 myoblasts, suggesting that morin prevented H2O2-induced cellular DNA damage. Furthermore, morin markedly enhanced the expression of heme oxygenase-1 (HO-1) associated with the induction and phosphorylation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and the inhibition of Kelch-like ECH-associated protein 1 (Keapl) expression. Notably, these events were eliminated by transient transfection with Nrf2-specific small interfering RNA. Additional experiments demonstrated that the activation of the Nrf2/HO-1 pathway by morin was mediated by the extracellular signal-regulated kinase (ERK) signaling cascade. This phenomenon was confirmed with suppressed Nrf2 phosphorylation and consequently diminished HO-1 expression in cells treated with a pharmacological inhibitor of ERK. Collectively, these results demonstrated that morin augments the cellular antioxidant defense capacity through the activation of Nrf2/HO-1 signaling, which involves the activation of the ERK pathway, thereby protecting C2C12 myoblasts from H2O2,-induced oxidative cytotoxicity.</P>

Ethanol Extract of Ganoderma lucidum Augments Cellular Anti-oxidant Defense through Activation of Nrf2/HO-1

Lee, Yoo-hwan,Kim, Jung-hee,Song, Choon-ho,Jang, Kyung-jeon,kim, Cheol-hong,Kang, Ji-Sook,Choi, Yung-hyun,Yoon, Hyun-Min KOREAN PHARMACOPUNCTURE INSTITUTE 2016 Journal of pharmacopuncture Vol.19 No.1

Objectives: The mushroom Ganoderma lucidum has been widely used as a traditional herbal medicine for many years. Although several studies have focused on the anti-oxidative activity of this mushroom, the molecular mechanisms underlying its activity have not yet been clearly established. The present study investigated the cytoprotective effect of ethanol extract of Ganoderma lucidum (EGL) against oxidative stress (hydrogen peroxide, $H_2O_2$) and elucidated the underlying mechanisms in a C2C12 myoblast cell line. Methods: Oxidative stress markers were determined by using the comet assay to measure reactive oxygen species (ROS) generation and deoxyribonucleic acid (DNA) damage. Cell viability and Western blotting analyses were employed to evaluate the cellular response to EGL and $H_2O_2$ in C2C12 cells. Transfection with nuclear factor erythroid 2-related factor 2 (Nrf2)-specific small interfering ribonucleic acid (siRNA) was conducted to understand the relationship between Nrf2 expression and $H_2O_2$-induced growth inhibition. Results: The results showed that EGL effectively inhibited $H_2O_2$-induced growth and the generation of ROS. EGL markedly suppressed $H_2O_2$-induced comet-like DNA formation and phosphorylation of histone H2AX at serine 139 ($p-{\gamma}H2AX$), a widely used marker of DNA damage, suggesting that EGL prevented $H_2O_2$-induced DNA damage. Furthermore, the EGL treatment effectively induced the expression of Nrf2, as well as heme oxygenase-1 (HO-1), with parallel phosphorylation and nuclear translocation of Nrf2 in the C2C12 myoblasts. However, zinc protoporphyrin IX, a HO-1 inhibitor, significantly abolished the protective effects of EGL against $H_2O_2$-induced accumulation of ROS and reduced cell growth. Notably, transient transfection with Nrf2-specific siRNA attenuated the cytoprotective effects and HO-1 induction by EGL, indicating that EGL induced the expression of HO-1 in an Nrf2-dependent manner. Conclusion: Collectively, these results demonstrate that EGL augments the cellular anti-oxidant defense capacity through activation of Nrf2/HO-1, thereby protecting C2C12 myoblasts from $H_2O_2$-induced oxidative cytotoxicity.

Antioxidant and cytoprotective effects of morin against hydrogen peroxide-induced oxidative stress are associated with the induction of Nrf-2-mediated HO-1 expression in V79-4 Chinese hamster lung fibroblasts

Lee, Moon Hee,Cha, Hee-Jae,Choi, Eun Ok,Han, Min Ho,Kim, Sung Ok,Kim, Gi-Young,Hong, Su Hyun,Park, Cheol,Moon, Sung-Kwon,Jeong, Soon-Jeong,Jeong, Moon-Jin,Kim, Wun-Jae,Choi, Yung Hyun Spandidos Publications 2017 International journal of molecular medicine Vol.39 No.3

<P>Natural phytochemicals of plant origin, including flavonoids, have been found to be potent antioxidants providing beneficial effects against oxidative stress-related diseases. The present study was carried out to investigate the antioxidant properties of morin, a flavonoid originally isolated from the flowering plants of the Moraceae family. Superoxide dismutase (SOD)-like activity and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(center dot+)) radical scavenging activity were determined. We also investigated the cytoprotective effects of morin against hydrogen peroxide (H2O2)-induced DNA damage and apoptosis in V79-4 Chinese hamster lung fibroblasts. Our results demonstrated that morin had strong scavenging effects against ABTS' radicals with enhanced SOD activity, which varied in a dose-dependent manner. Morin was found to reduce H2O2-induced intracellular reactive oxygen species generation and nuclear DNA damage, and it recovered cell viability damaged by H2O2 via inhibition of mitochondrial dysfunction-mediated apoptosis. Notably, the treatment of V79-4 cells with morin markedly enhanced the expression of heme oxygenase-1 (HO-1) but not quinone oxidoreductase-1, which was associated with the increased expression and phosphorylation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and the downregulation of Kelch-like ECH-associated protein 1 expression. Based on our findings, we conclude that morin effectively ameliorated oxidative stress-induced DNA damage through intrinsic free radical scavenging activity and activation of the Nrf2/HO-1 pathway.</P>

진피 메탄올 추출물의 활성산소종 생성을 통한 인체 백혈병 세포의 apoptosis 유발

김가희(Ga Hee Kim),이문희(Moon Hee Lee),한민호(Min Ho Han),박철(Cheol Park),홍수현(Su Hyun Hong),최영현(Yung Hyun Choi) 한국생명과학회 2013 생명과학회지 Vol.23 No.8

진피(Citri Pericarpium)의 항암작용 기전 해석을 위하여 U937 백혈병 세포의 apoptosis 유발에 미치는 메탄올추출물(EMCP)의 영향을 조사하였으며, apoptosis 조절에 중요한 몇 가지 유전자들의 발현 및 활성 변화, ROS의 생성 변화를 조사하였다. EMCP 처리에 의한 U937 세포의 증식 억제는 apoptosis 유도와 연관성이 있음을 DAPI 염색을 통한 apoptotic body 출현의 증가 및 Flow cytometry 분석에 의한 Sub-G1기 세포 빈도의 증가로 확인하였다. EMCP 처리에 의한 apoptosis 유도에서 Bax 발현 증가, caspases의 활성 및 PARP의 단편화 등이 동반되었으며, ROS 생성의 증가와 연관성이 있었다. 산화적 손상에 대해 세포나 조직을 보호하는 역할을 하는 것으로 알려진 세포 내 항산화 효소인 HO-1의 발현이 EMCP의 처리에 의해 증가되었으나 ROS 생성 억제제인 NAC의 전처리에 의해 감소된 HO-1의 발현은 전사인자인 Nrf2의 핵으로의 이동 억제와 관련되어 있었다. 이상의 결과에서 EMCP 처리에 의한 U937 세포의 apoptosis 유발에는 ROS 생성의 증가와 pNrf2에 의해 조절되는 HO-1의 발현 증가가 중요한 기전으로 작용한다는 것을 알 수 있었다. 이러한 자료는 진피의 항암기전 해석을 이해하는데 중요한 기초자료로서 활용될 수 있을 것으로 생각된다. Citri Pericarpium is one of the most commonly used traditional herbal medicines in Korea, China, and Japan. Its extracts have many properties including the treatment of indigestion and inflammatory respiratory syndromes such as bronchitis and asthma. However, the underlying molecular mechanisms of anti-cancer activity and molecular targets are not fully understood. In this work, we investigated the anti-proliferative activity of Citri Pericapium (EMCP) methanol extract on reactive oxygen species (ROS) production and the association of these effects with apoptotic cell death using U937 human leukemia cells in vitro. EMCP treatment decreased cell proliferation in a dose-dependent manner following an increase of the sub-G1 phase, the down-regulation of Bax proteins, the activation of caspases, the degradation of poly (ADP-ribose) polymerase proteins (PARP), and the induction of ROS generation. However, the quenching of ROS generation by N-acetyl-L-cysteine administration, a scavenger of ROS, reversed the EMCP-induced apoptosis effects. In addition, heme oxygenase-1 expression also recovered by inhibiting the nuclear translocation of phosphorylated NF-E2-related factor 2. Taken together, our data indicate that ROS are involved as key mediators in the early molecular events in the EMCP-induced apoptotic pathway.

제브라피쉬에서 장신경계에 의한 장운동 조절

이명호,문현이,권영숙,맹학영,김철희 충남대학교 생물공학연구소 2011 생물공학연구지 Vol.17 No.-

평면형 Bi-Sb 다중접합 열전변환기의 특성

이현철,유호종,김진섭,함성호,신장규,이종현,이정희,권성원,박세일 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

A planar Bi-Sb multijunction thermal converter for the precise measurements of ac voltage and current has been fabricated and its characteristics was discussed. In order to convert ac power into heat, a bifilar thin film Pt-heater, which could cancel its Thomson and Peltier effects, was prepared on the Si_(3)N_(4)/SiO_(2)/Si_(3)N_(4) diaphragm for the thermal isolation between heater and silicon substrate. To convert the temperature or the heat generated by the heater into dc voltage and current, hot and cold junctions of the Bi-Sb thermopile, which has a large difference in Seebeck coefficients, were formed on the dielectric diaphragm and the silicon substrate, respectively. The respective thermal sensitivity of the thermal converter with a bifilar heater was about 10.1 mV/mW and 14.8 mV/mW in the air and vacuum, which is about eight times higher than that of commercial 3-dimensional thermal converter. In the case of ac 2 V-input voltage, the ac-dc voltage transfer difference was about ±2.0 ppm, and in the case of ac 10 mA-input current, the ac-dc current transfer difference was about ± 0.6 ppm, in the frequency range from 10 Hz to 10 kHz.

참나무 群落地의 植物群集構造分析 : Ⅰ. 白雲山의 植物群集構造分析 Ⅰ. Plant Distribution and vegetation structure in Mt. Bakwoon

趙顯瑞,李喆浩 진주산업대학교 1998 論文集 Vol.37 No.-

백운산 내회지역과 지리산 대원계곡의 삼림군집구조를 파악하여 우량종 육성에 필요한 자료를 분석한 결과는 다음과 같다. 1. 백운산지역 95개 조사지를 TWINSPAN에 의하여 classification을 분석한 결과, 남사면에서는 양수인 소나무 군집으로 구분되었으며, 북사면에서는 활엽수흔효군집으로 구분되었다. 2. 백운산지역 조사지는 DCA에 의하여 1, 2축에 우측에서 좌측으로 소나무군집, 굴참무군집, 졸참나무-굴참나무군집, 졸참나무군집, 서어나무군집으로 분리되었고, 상, 하로 신갈나무군집, 활엽수흔효군집, 고로쇠나무군집 등의 8개 군집으로 분리되어 TWINSPAN보다 DCA방법이 효과적이었다. 3. 백운산 지역 군집간의 유사도지수를 분석한 결과, 소나군집과 졸참나무군집, 소나무군집과 서어나무군집, 소나무군집과 고로쇠나무군집, 신갈나무군집과 고로쇠나무군집의 유사도지수가 20%미만을 나타내어 이질적인 군집임을 알 수 있었고, 졸참나무-굴참나무군집과 굴참나무군집, 졸참나무군집, 활엽수흔효군집 그리고 굴참나무군집과 활엽수흔효군집간에는 55% 이상의 높은 값을 나타내었다. 4. 백운산지역 토양 환경인자의 DCA분석에서 토양산도를 제외하고 모든 인자의 A군집(소나무군집)에서 E군집(서어나무군집)으로 갈수록 증가하는 경향이었다. 5. 백운산지역 토양산도, 수분함량, 유기물함량 및 K^+, Ca^++, Mg^++ 등 토양환경요인을 DCA기법을 적용한 결과, 대부분의 요인에서 소나무, 신갈나무군집은 낮은 계급을 나타내었고, 서어나무군집, 활엽수흔효군집, 고로쇠나무군집 등에서는 높은 계급에 위치하고 있었다. This paper aims at analyzing the plant community in Mt. Bakwoon area. The plant community in Mt. Bakwoon was divided into 95 plots by clumped sampling method. According to DCA ordination, Mt. Bakwoon is composed of Pinus densiflora, Quercus variabilis, and Q. serrata communities. The similarity index between Quercus variabilis and mixed stands of broad leaved trees was more than 55%.

한국 성인에서 색도플러 초음파를 이용한 척추동맥 혈류량의 정상치

홍현숙,차장규,박성진,조준희,박재성,김대호,이혜경,안현철 대한초음파의학회 2003 ULTRASONOGRAPHY Vol.22 No.3

막성 및 연골성 탈회골기질에 의한 골유도와 재생에 관한 연구

김호철,정현대 전남대학교 치과대학 1995 전남치대논문집 Vol.7 No.1

Since bone matrix is konwn to contain osteoinductive substance to form bone by endochondral ossification, there are much clinical interests concerning it. But there are still controversies about clinical effects, the methods of osteoinduction and preparations of bone matrix. About 700㎛ demineralized endochondral and intramembranous bone matrix particles, which have different origin in development were made from long bone and calvaria of rabbit respectively. They were allografted into the artificial defects of medial surface of tibia. The mode of bone formation and regeneration are stuided by microscopic and fluorescent observation. 1. A lot of fibrin network formed among the demineralized bone particles after 3 days of graft. 2. Lots of spindle shaped cells appeared around the particles and begin to bone formation 7 days after graft. Bone formation was mainly taking place from the host bone in control group. 3. Active bone induction by endochondral and intramembranous bone formation from both kinds of the matrix particles, which were being resorbed by multinucleated cells, was noted. 4. More rapid bone regeneration and maturity were seen in demineralized bone grafted groups than in control in grinding preparations and fluorescent microscopy. 5. There is no considerable difference of osteoinductivity between the membranous and endochondral bone matrices. These results suggest that endochondral bone formation is not critical in osteoinduction by demineralized bone matrices and both types of matrices can be applicated clinically in bone graft.