• Title/Summary/Keyword: Cell hypoxia

Search Result 307, Processing Time 0.024 seconds

Effects of Polygoni Multiflori Radix on Cerebral Ischemia of Hyperlipidemic Rats. (하수오가 고지혈증 흰쥐의 허혈성 뇌손상에 미치는 영향)

  • Lee Young-Hyo;Lee Won-Chul
    • The Journal of Korean Medicine
    • /
    • v.26 no.3 s.63
    • /
    • pp.146-161
    • /
    • 2005
  • Objectives : This study investigated neuroprotective effects of Polygoni Multiflori Radix on cerebral ischemia of hyperlipidemic rats. Methods : Effects of Polygoni Multiflori Radix were evaluated with changes of infarct size after He focal cerebral ischemia induced by the middle cerebral artery occlusion, changes of pyramidal neurons and expressions of Bax and Bcl-2 apoptosis regulating factors after global cerebral ischemia, and changes of serum lipid revels after cerebral ischemia. Results & Conclusions : Results obtained were as follows; 1. Polygoni Multiflori Radix did net reduce the focal cerebral infarct size induced by the middle cerebral artery occlusion under both hyperlipidemic and normal-lipid conditions. 2. Polygoni Multiflori Radix significantly reduced the increase of neuronal cell death in CAl region of hippocampus induced by the global cerebral ischemia under both hyperlipidemic and normal-lipid conditions. 3. Polygoni Multiflori Radix significantly reduced the increase of Bax expression in the CAl region of the hippocampus induced by global cerebral ischemia under both hyperlipidemic and normal-lipid conditions. 4. Polygoni Multiflori Radix significantly increased Bc1-2 expression in the CA1 region of the hippocampus after global cerebral ischemia under normal-lipid condition, but was not effective on that under hyperlipidemic condition. 5. Polygoni Multiflori Radix was not effective on serum total-cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride levels under normal-lipid conditions, irrespective of focal cerebral infarct or global cerebral ischemia. 6. Polygoni Multiflori Radix significantly reduced the increase of serum total-cholesterol and triglyceride levels, and increased serum LDL-cholesterol level under hyperlipidemic conditions, irrespective of foc31 cerebral infarct or global cerebral ischemia.

  • PDF

Neuroprotective effects of L-carnitine against oxygen-glucose deprivation in rat primary cortical neurons

  • Kim, Yu-Jin;Kim, Soo-Yoon;Sung, Dong-Kyung;Chang, Yun-Sil;Park, Won-Soon
    • Clinical and Experimental Pediatrics
    • /
    • v.55 no.7
    • /
    • pp.238-248
    • /
    • 2012
  • Purpose: Hypoxic-ischemic encephalopathy is an important cause of neonatal mortality, as this brain injury disrupts normal mitochondrial respiratory activity. Carnitine plays an essential role in mitochondrial fatty acid transport and modulates excess acyl coenzyme A levels. In this study, we investigated whether treatment of primary cultures of rat cortical neurons with L-carnitine was able to prevent neurotoxicity resulting from oxygen-glucose deprivation (OGD). Methods: Cortical neurons were prepared from Sprague-Dawley rat embryos. L-Carnitine was applied to cultures just prior to OGD and subsequent reoxygenation. The numbers of cells that stained with acridine orange (AO) and propidium iodide (PI) were counted, and lactate dehydrogenase (LDH) activity and reactive oxygen species (ROS) levels were measured. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and the terminal uridine deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay were performed to evaluate the effect of L-carnitine (1 ${\mu}M$, 10 ${\mu}M$, and 100 ${\mu}M$) on OGD-induced neurotoxicity. Results: Treatment of primary cultures of rat cortical neurons with L-carnitine significantly reduced cell necrosis and prevented apoptosis after OGD. L-Carnitine application significantly reduced the number of cells that died, as assessed by the PI/AO ratio, and also reduced ROS release in the OGD groups treated with 10 ${\mu}M$ and 100 ${\mu}M$ of L-carnitine compared with the untreated OGD group (P<0.05). The application of L-carnitine at 100 ${\mu}M$ significantly decreased cytotoxicity, LDH release, and inhibited apoptosis compared to the untreated OGD group (P<0.05). Conclusion: L-Carnitine has neuroprotective benefits against OGD in rat primary cortical neurons in vitro.

Regulation of HIF-1α stability by lysine methylation

  • Baek, Sung Hee;Kim, Keun Il
    • BMB Reports
    • /
    • v.49 no.5
    • /
    • pp.245-246
    • /
    • 2016
  • The level and activity of critical regulatory proteins in cells are tightly controlled by several tiers of post-translational modifications. HIF-1α is maintained at low levels under normoxia conditions by the collaboration between PHD proteins and the VHL-containing E3 ubiquitin ligase complex. We recently identified a new physiologically relevant mechanism that regulates HIF-1α stability in the nucleus in response to cellular oxygen levels. This mechanism is based on the collaboration between the SET7/9 methyltransferase and the LSD1 demethylase. SET7/9 adds a methyl group to HIF-1α, which triggers degradation of the protein by the ubiquitin-proteasome system, whereas LSD1 removes the methyl group, leading to stabilization of HIF-1α under hypoxia conditions. In cells from knock-in mice with a mutation preventing HIF-1α methylation (Hif1αKA/KA), HIF-1α levels were increased in both normoxic and hypoxic conditions. Hif1αKA/KA knock-in mice displayed increased hematological parameters, such as red blood cell count and hemoglobin concentration. They also displayed pathological phenotypes; retinal and tumor-associated angiogenesis as well as tumor growth were increased in Hif1αKA/KA knock-in mice. Certain human cancer cells exhibit mutations that cause defects in HIF-1α methylation. In summary, this newly identified methylation-based regulation of HIF-1α stability constitutes another layer of regulation that is independent of previously identified mechanisms.

Extracts from Rhizopus oryzae KSD-815 of Korean Traditional Nuruk Confer the Potential to Inhibit Hypertension, Platelet Aggregation, and Cancer Metastasis in vitro

  • Lee, Sang-Jin;Bae, Hyun-Jin;Ryu, Ji-Yeon;Lee, Dae-Young;Kim, Gye-Won;Baek, Na-Min;Kwon, Moo-Sik;Hong, Sung-Youl
    • Food Science and Biotechnology
    • /
    • v.18 no.6
    • /
    • pp.1423-1429
    • /
    • 2009
  • Rhizopus oryzae KSD-815 was isolated from nuruk that has been used to make Korean traditional wines. This study was performed to investigate the effect of cultures of R. oryzae KSD-815 on cardiovascular disorders and cancer metastasis. Firstly, these cultures were sequentially fractionationed with n-hexane (TAHe), ethylacetate (TAE), n-butanol (TAB), and $H_2O$ (TAW). The TAE inhibited the activity of angiotensin-converting enzyme (ACE) and TAB suppressed platelet aggregation in vitro. TAE and TAB inhibited cell motility of human breast cancer cells. Furthermore, TAW interrupted the formation of neovasculature and tube-like structure, and down-regulated the expression of angiogenic factors, basic fibroblast growth factor (bFGF), tumor necrosis factor-$\alpha$ (TNF-$\alpha$), and hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$) in breast cancer cells. These results indicated that cultures of R. oryzae KSD-815 display the inhibitory activities on hypertension, platelet aggregation, and metastasis, and suggest that these cultures might be further probed for the purposes as therapeutic agents or dietary supplements.

Microarray Analysis of Alteration in Gene Expression by Acori graminei rhizoma (AGR) Water-Extract in a Hypoxic Model of Cultured Rat Cortical Cells (흰쥐 대뇌세포의 저산소증 모델에서 석창포(石菖浦 Acori graminei rhizoma. AGR)에 의한 유전자 표현 변화의 microarray 분석)

  • Park, Dong-Jun;Jung, Seung-Hyun;Moon, Il-Soo;Lee, Won-Chol;Shin, Gil-Jo
    • Journal of Life Science
    • /
    • v.17 no.1 s.81
    • /
    • pp.150-161
    • /
    • 2007
  • Acori graminei Rhizomn (AGR) is a perennial herb which has been used clinically as a traditional oriental medicine against stroke, Alzheimer's disease, and vascular dementia. We investigated the effect of AGR on the modulation of gene expression profile in a hypoxic model of cultured rat cortical cells. Rat cerebrocortical cells were grown in Neurobasal medium. On DIV12, cells were treated with AGR $(10ug/m\ell)$, given a hypoxic shock (2% $O_2$, 3 hr) on DIV14, and total RNAs were prepared one day after shock. Microarray analyses indicated that the expression levels of most genes were altered within the global M values +0.5 and -0.5, i.e., 40% increase or decrease. There were 750 genes which were upregulated by < global M +0,2, while 700 genes were downregulated by > global M -0.2. The overall profile of gene expression suggests that AGR suppresses apoptosis (upregulation of anti-apopotic genes such as TEGT, TIEG, Dad, p53, and downregulation of pro-apopotic genes such as DAPK, caspase 2, pdcd8), ROS (upregulation of RARa, AhR), and that AGR has neurotrophic effects (upregulation of Aktl, Akt2). These results provide a platform for investigation of the molecular mechanism of the effect of AGR in neuroprotection.

Triptolide improves myocardial fibrosis in rats through inhibition of nuclear factor kappa B and NLR family pyrin domain containing 3 inflammasome pathway

  • Shen, Jianyao;Ma, Hailiang;Wang, Chaoquan
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.25 no.6
    • /
    • pp.533-543
    • /
    • 2021
  • Myocardial fibrosis (MF) is the result of persistent and repeated aggravation of myocardial ischemia and hypoxia, leading to the gradual development of heart failure of chronic ischemic heart disease. Triptolide (TPL) is identified to be involved in the treatment for MF. This study aims to explore the mechanism of TPL in the treatment of MF. The MF rat model was established, subcutaneously injected with isoproterenol and treated by subcutaneous injection of TPL. The cardiac function of each group was evaluated, including LVEF, LVFS, LVES, and LVED. The expressions of ANP, BNP, inflammatory related factors (IL-1β, IL-18, TNF-α, MCP-1, VCAM1), NLRP3 inflammasome factors (NLRP3, ASC) and fibrosis related factors (TGF-β1, COL1, and COL3) in rats were dete cted. H&E staining and Masson staining were used to observe myocardial cell inflammation and fibrosis of rats. Western blot was used to detect the p-P65 and t-P65 levels in nucleoprotein of rat myocardial tissues. LVED and LVES of MF group were significantly upregulated, LVEF and LVFS were significantly downregulated, while TPL treatment reversed these trends; TPL treatment downregulated the tissue injury and improved the pathological damage of MF rats. TPL treatment downregulated the levels of inflammatory factors and fibrosis factors, and inhibited the activation of NLRP3 inflammasome. Activation of NLRP3 inflammasome or NF-κB pathway reversed the effect of TPL on MF. Collectively, TPL inhibited the activation of NLRP3 inflammasome by inhibiting NF-κB pathway, and improved MF in MF rats.

6-sialyllactose ameliorates dihydrotestosterone-induced benign prostatic hyperplasia through suppressing VEGF-mediated angiogenesis

  • Kim, Eun-Yeong;Jin, Bo-Ram;Chung, Tae-Wook;Bae, Sung-Jin;Park, Hyerin;Ryu, Dongryeol;Jin, Ling;An, Hyo-Jin;Ha, Ki-Tae
    • BMB Reports
    • /
    • v.52 no.9
    • /
    • pp.560-565
    • /
    • 2019
  • Benign prostatic hyperplasia (BPH), a common disease in elderly males, is accompanied by non-malignant growth of prostate tissues, subsequently causing hypoxia and angiogenesis. Although VEGF-related angiogenesis is one of the therapeutic targets of prostate cancer, there is no previous study targeting angiogenesis for treatment of BPH. Dihydrotestosterone (DHT)-induced expressions of vascular endothelial growth factor (VEGF) in prostate epithelial RWPE-1 cells and human umbilical vascular endothelial cells (HUVECs). Conditioned media (CM) from DHT-treated RWPE-1 cells were transferred to HUVECs. Then, 6SL inhibited proliferation, VEGFR-2 activation, and tube formation of HUVECs transferred with CM from DHT-treated RWPE-1 cells. In the rat BPH model, 6SL reduced prostate weight, size, and thickness of the prostate tissue. Formation of vessels in prostatic tissues were also reduced with 6SL treatment. We found that 6SL has an ameliorative effect on in vitro and in vivo the BPH model via inhibition of VEGFR-2 activation and subsequent angiogenesis. These results suggest that 6SL might be a candidate for development of novel BPH drugs.

Recent progress (2015-2020) in the investigation of the pharmacological effects and mechanisms of ginsenoside Rb1, a main active ingredient in Panax ginseng Meyer

  • Lin, Zuan;Xie, Rongfang;Zhong, Chenhui;Huang, Jianyong;Shi, Peiying;Yao Hong
    • Journal of Ginseng Research
    • /
    • v.46 no.1
    • /
    • pp.39-53
    • /
    • 2022
  • Ginsenoside Rb1 (Rb1), one of the most important ingredients in Panax ginseng Meyer, has been confirmed to have favorable activities, including reducing antioxidative stress, inhibiting inflammation, regulating cell autophagy and apoptosis, affecting sugar and lipid metabolism, and regulating various cytokines. This study reviewed the recent progress on the pharmacological effects and mechanisms of Rb1 against cardiovascular and nervous system diseases, diabetes, and their complications, especially those related to neurodegenerative diseases, myocardial ischemia, hypoxia injury, and traumatic brain injury. This review retrieved articles from PubMed and Web of Science that were published from 2015 to 2020. The molecular targets or pathways of the effects of Rb1 on these diseases are referring to HMGB1, GLUT4, 11β-HSD1, ERK, Akt, Notch, NF-κB, MAPK, PPAR-γ, TGF-β1/Smad pathway, PI3K/mTOR pathway, Nrf2/HO-1 pathway, Nrf2/ARE pathway, and MAPK/NF-κB pathway. The potential effects of Rb1 and its possible mechanisms against diseases were further predicted via Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and disease ontology semantic and enrichment (DOSE) analyses with the reported targets. This study provides insights into the therapeutic effects of Rb1 and its mechanisms against diseases, which is expected to help in promoting the drug development of Rb1 and its clinical applications.

Neuroprotective Effects of Acorus gramineus Soland. on Oxygen-Glucose Deprivation/Reoxygenation-Induced β-amyloid Production in SH-SY5Y Neuroblastoma Cells (허혈-재관류 유도 SH-SY5Y 모델에서 베타아밀로이드 생성에 미치는 석창포 추출물에 대한 뇌 신경보호 효과)

  • Su Young Shin;Jin-Woo Jeong;Chul Hwan Kim;Eun Jung Ahn;Seung Young Lee;Chang-Min Lee;Kyung-Min Choi
    • Proceedings of the Plant Resources Society of Korea Conference
    • /
    • 2021.04a
    • /
    • pp.58-58
    • /
    • 2021
  • Although hypoxic/ischemic injury is thought to contribute to the incidence of Alzheimer disease (AD), the molecular mechanism that determines the relationship between hypoxia-induced β-amyloid (Aβ) generation and development of AD is not yet known. In this study, we investigated the protective effects of Acorus gramineus Soland. (AGS) on oxygen-glucose deprivation/reoxygenation (OGD/R)-induced A β production in SH-SY5Y human neuroblastoma cells. Pretreatment of these cells with AGS significantly attenuated OGD/R-induced production of reactive oxygen species (ROS) and elevation of levels of malondialdehyde, nitrite (NO), prostaglandin E2 (PGE2), cytokines (TNF-α, IL-1β and IL-6) and glutathione, as well as superoxide dismutase activity. AGS also reduced OGD/R-induced expression of the apoptotic protein caspase-3, the apoptosis regulator Bcl-2, and the autophagy protein becn-1. Finally, AGS reduced OGD/R-induced Aβ production and cleavage of amyloid precursor protein, by inhibiting secretase activity and suppressing the autophagic pathway. Although supporting data from in vivo studies are required, our results indicate that AGS may prevent neuronal cell damage from OGD/R-induced toxicity.

  • PDF

Implication of High Mobility Group Box 1 (HMGB1) in Multicellular Tumor Spheroid (MTS) Culture-induced Epithelial-mesenchymal Transition (Multicellular tumor spheroid (MTS) 배양에 의한 EMT에서 HMGB1의 역할)

  • Lee, Su Yeon;Ju, Min Kyung;Jeon, Hyun Min;Kim, Cho Hee;Park, Hye Gyeong;Kang, Ho Sung
    • Journal of Life Science
    • /
    • v.29 no.1
    • /
    • pp.9-17
    • /
    • 2019
  • As tumors develop, they encounter microenvironmental stress, such as hypoxia and glucose depletion, due to poor vascular function, thereby leading to necrosis, which is observed in solid tumors. Necrotic cells are known to release cellular cytoplasmic contents, such as high mobility group box 1 (HMGB1), into the extracellular space. The release of HMGB1, a proinflammatory and tumor-promoting cytokine, plays an important role in promoting inflammation and metabolism during tumor development. Recently, HMGB1 was shown to induce the epithelial-mesenchymal transition (EMT) and metastasis. However, the underlying mechanism of the HMGB1-induced EMT, invasion, and metastasis is unclear. In this study, we showed that noninvasive breast cancer cells MCF-7 formed tightly packed, rounded spheroids and that the cells in the inner regions of a multicellular tumor spheroid (MTS), an in vitro model of a solid tumor, led to necrosis due to an insufficient supply of O2 and glucose. In addition, after 7 d of MTS culture, the EMT was induced via the transcription factor Snail. We also showed that HMGB1 receptors, including RAGE, TLR2, and TLR4, were induced by MTS culture. RAGE, TLR2, and TLR4 shRNA inhibited MTS growth, supporting the idea that RAGE/TLR2/TLR4 play critical roles in MTS growth. They also prevented MTS culture-induced Snail expression, pointing to RAGE/TLR2/TLR4-dependent Snail expression. RAGE, TLR2, and TLR4 shRNA suppressed the MTS-induced EMT. In human cancer tissues, high levels of RAGE, TLR2, and TLR4 were detected. These findings demonstrated that the HMGB-RAGE/TLR2/TLR4-Snail axis played a crucial role in the growth of the MTS and MTS culture-induced EMT.