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1.
Luminescence ; 39(4): e4735, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38565323

RESUMO

In this work, a near-infrared emissive photosensitizer of 3,3-dimethyl-N,N-diphenyl-2-(thiophen-2-yl)-3H-indol-6-amine functionlized benzothiazolium (DPITT) was developed. DPITT exhibited aggregation-induced emission effect and potent type I and II reactive oxygen species generation capacities after white light irradiation. Taking advantage of the cationic feature, DPITT penetrated the cell membrane and selectively accumulated in the mitochondria in living cells. Upon white light irradiation, the photosensitized DPITT was able to induce mitochondrial dysfunction, leading to cell death. Photosensitized DPITT was further applied to disrupt the multicellular tumour spheroids, demonstrating its potential application in inhibiting hypoxic solid tumours.


Assuntos
Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Luz , Mitocôndrias/patologia , Mitocôndrias/efeitos da radiação
2.
Breast Cancer ; 31(3): 426-439, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38472737

RESUMO

Enhancing radiotherapy sensitivity is crucial for improving treatment outcomes in triple-negative breast cancer (TNBC) patients. In this study, we investigated the potential of targeting Elongin B (ELOB) to enhance radiotherapy efficacy in TNBC. Analysis of TNBC patient cohorts revealed a significant association between high ELOB expression and poor prognosis in patients who received radiation therapy. Mechanistically, we found that ELOB plays a pivotal role in regulating mitochondrial function via modulating mitochondrial DNA expression and activities of respiratory chain complexes. Targeting ELOB effectively modulated mitochondrial function, leading to enhanced radiosensitivity in TNBC cells. Our findings highlight the importance of ELOB as a potential therapeutic target for improving radiotherapy outcomes in TNBC. Further exploration of ELOB's role in enhancing radiotherapy efficacy may provide valuable insights for developing novel treatment strategies for TNBC patients.


Assuntos
Tolerância a Radiação , Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/patologia , Feminino , Linhagem Celular Tumoral , Mitocôndrias/efeitos da radiação , Mitocôndrias/metabolismo , Prognóstico , Fatores de Transcrição/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Animais , DNA Mitocondrial/genética
3.
Radiat Environ Biophys ; 62(2): 213-220, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36941405

RESUMO

Vascular endothelial growth factor (VEGF) is closely related to angiogenesis. Anticancer therapy by inhibiting VEGF signaling is well established. However, the role of VEGF in cell-cell communication during the response to ionizing radiation is not well understood. Here, we examined the role of VEGF on radiosensitivity of cells. The addition of recombinant VEGF (rVEGF) on cultured rat C6 glioma cells showed a radioprotective effects on X-ray irradiation and reduced oxidative stress. These effects were also observed by endogenous VEGF in supernatant of C6 glioma cells. Reduction of oxidative stress by VEGF is suggested to underlie the radioprotective effects. The mechanism of VEGF-induced reduction of oxidative stress was indicated by a decreased oxygen consumption rate (OCR) in mitochondria. However, the number of DNA double-strand breaks (DSB) immediately after irradiation was not reduced by the treatment with VEGF. These results suggest that VEGF plays a role in cell survival after irradiation by controlling the oxidative condition through mitochondrial function that is independent of the efficiency of DSB induction.


Assuntos
Glioma , Fator A de Crescimento do Endotélio Vascular , Ratos , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/farmacologia , Glioma/radioterapia , Glioma/metabolismo , Mitocôndrias/efeitos da radiação
4.
J Photochem Photobiol B ; 239: 112643, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36610350

RESUMO

Low-level laser therapy, or photobiomodulation, utilizes red or near-infrared light for the treatment of pathological conditions due to the presence of intracellular photoacceptors, such as mitochondrial cytochrome c oxidase, that serve as intermediates for the therapeutic effects. We present an in-detail analysis of the effect of low-intensity LED red light irradiation on the respiratory chain of brain mitochondria. We tested whether low-level laser therapy at 650 nm could alleviate the brain mitochondrial dysfunction in the model of acute hypobaric hypoxia in mice. The irradiation of the mitochondrial fraction of the left cerebral cortex with low-intensity LED red light rescued Complex I-supported respiration during oxidative phosphorylation, normalized the initial polarization of the inner mitochondrial membrane, but has not shown any significant effect on the activity of Complex IV. In comparison, the postponed effect (in 24 h) of the similar transcranial irradiation following hypoxic exposure led to a less pronounced improvement of the mitochondrial functional state, but normalized respiration related to ATP production and membrane polarization. In contrast, the similar irradiation of the mitochondria isolated from control healthy animals exerted an inhibitory effect on CI-supported respiration. The obtained results provide significant insight that can be beneficial for the development of non-invasive phototherapy.


Assuntos
Encéfalo , Hipóxia , Terapia com Luz de Baixa Intensidade , Mitocôndrias , Animais , Camundongos , Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hipóxia/complicações , Hipóxia/metabolismo , Hipóxia/radioterapia , Raios Infravermelhos/uso terapêutico , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Pressão/efeitos adversos , Respiração Celular/efeitos da radiação
5.
J Biol Chem ; 299(2): 102825, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36567017

RESUMO

Long noncoding RNAs (lncRNAs) are emerging as essential players in multiple biological processes. Mitochondrial dynamics, comprising the continuous cycle of fission and fusion, are required for healthy mitochondria that function properly. Despite long-term recognition of its significance in cell-fate control, the mechanism underlying mitochondrial fusion is not completely understood, particularly regarding the involvement of lncRNAs. Here, we show that the lncRNA HITT (HIF-1α inhibitor at translation level) can specifically localize in mitochondria. Cells expressing higher levels of HITT contain fragmented mitochondria. Conversely, we show that HITT knockdown cells have more tubular mitochondria than is present in control cells. Mechanistically, we demonstrate HITT directly binds mitofusin-2 (MFN2), a core component that mediates mitochondrial outer membrane fusion, by the in vitro RNA pull-down and UV-cross-linking RNA-IP assays. In doing so, we found HITT disturbs MFN2 homotypic or heterotypic complex formation, attenuating mitochondrial fusion. Under stress conditions, such as ultraviolet radiation, we in addition show HITT stability increases as a consequence of MiR-205 downregulation, inhibiting MFN2-mediated fusion and leading to apoptosis. Overall, our data provide significant insights into the roles of organelle (mitochondria)-specific resident lncRNAs in regulating mitochondrial fusion and also reveal how such a mechanism controls cellular sensitivity to UV radiation-induced apoptosis.


Assuntos
GTP Fosfo-Hidrolases , Mitocôndrias , Dinâmica Mitocondrial , Proteínas Mitocondriais , Complexos Multiproteicos , RNA Longo não Codificante , GTP Fosfo-Hidrolases/química , GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Dinâmica Mitocondrial/efeitos da radiação , Proteínas Mitocondriais/química , Proteínas Mitocondriais/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Raios Ultravioleta , MicroRNAs/metabolismo , Apoptose/efeitos da radiação , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Membranas Mitocondriais/metabolismo
6.
Sci Rep ; 12(1): 1310, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079059

RESUMO

Epigallocatechin gallate (EGCG) has the effect to protect skin from ultraviolet B (UVB) induced damages, but it is unstable under ambient conditions, being susceptible to become brown in color. Gallocatechin gallate (GCG), an epimer counterpart of EGCG, is more stable chemically than EGCG. The potential effects of GCG against UVB-induced skin damages has not been available. The objective of this study was to investigate the protective effects of GCG against UVB-induced skin photodamages. GCG was topically applied on the skin of hairless mice at three dosage levels (LL, 12.5 mg/mL; ML 25 mg/mL; HL, 50 mg/mL), with EGCG and a commercially available baby sunscreen lotion SPF50 PA+++ as control. The mice were then irradiated by UVB (fluence rate 1.7 µmol/m2 s) for 45 min. The treatments were carried out once a day for 6 consecutive days. Skin measurements and histological studies were performed at the end of experiment. The results show that GCG treatments at ML and HL levels inhibited the increase in levels of skin oil and pigmentation induced by UVB irradiation, and improved the skin elasticity and collagen fibers. GCG at ML and HL levels inhibited the formation of melanosomes and aberrations in mitochondria of UVB-irradiated skin in hairless mice. It is concluded that GCG protected skin from UVB-induced photodamages by improving skin elasticity and collagen fibers, and inhibiting aberrations in mitochondria and formation of melanosomes.


Assuntos
Catequina/análogos & derivados , Pele/efeitos dos fármacos , Pele/efeitos da radiação , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos , Administração Cutânea , Animais , Catequina/administração & dosagem , Feminino , Masculino , Melanossomas/efeitos dos fármacos , Melanossomas/efeitos da radiação , Camundongos , Camundongos Pelados , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Vaselina/administração & dosagem , Doses de Radiação
7.
Int J Mol Sci ; 23(2)2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35054859

RESUMO

The damaging effects of ionizing radiation (IR) on bone mass are well-documented in mice and humans and are most likely due to increased osteoclast number and function. However, the mechanisms leading to inappropriate increases in osteoclastic bone resorption are only partially understood. Here, we show that exposure to multiple fractions of low-doses (10 fractions of 0.4 Gy total body irradiation [TBI]/week, i.e., fractionated exposure) and/or a single exposure to the same total dose of 4 Gy TBI causes a decrease in trabecular, but not cortical, bone mass in young adult male mice. This damaging effect was associated with highly activated bone resorption. Both osteoclast differentiation and maturation increased in cultures of bone marrow-derived macrophages from mice exposed to either fractionated or singular TBI. IR also increased the expression and enzymatic activity of mitochondrial deacetylase Sirtuin-3 (Sirt3)-an essential protein for osteoclast mitochondrial activity and bone resorption in the development of osteoporosis. Osteoclast progenitors lacking Sirt3 exposed to IR exhibited impaired resorptive activity. Taken together, targeting impairment of osteoclast mitochondrial activity could be a novel therapeutic strategy for IR-induced bone loss, and Sirt3 is likely a major mediator of this effect.


Assuntos
Reabsorção Óssea/patologia , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Osteoclastos/metabolismo , Osteoclastos/efeitos da radiação , Radiação Ionizante , Animais , Osso Esponjoso/patologia , Osso Esponjoso/efeitos da radiação , Respiração Celular/efeitos da radiação , Fracionamento da Dose de Radiação , Masculino , Camundongos Endogâmicos C57BL , Sirtuína 3/metabolismo
8.
Biochem Biophys Res Commun ; 595: 7-13, 2022 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-35091109

RESUMO

The intestinal tract is an essential component of the body's immune system, and is extremely sensitive to exposure of ionizing radiation. While ionizing radiation can effectively induce multiple forms of cell death, whether it can also promote ferroptosis in intestinal cells and the possible interrelationship between ferroptosis and intestinal immune function has not been reported so far. Here, we found that radiation-induced major ultrastructural changes in mitochondria of small intestinal epithelial cells and the changes induced in iron content and MDA levels in the small intestine were consistent with that observed during cellular ferroptosis, thus suggesting occurrence of ferroptosis in radiation-induced intestinal damage. Moreover, radiation caused a substantial increase in the expression of ferroptosis-related factors such as LPCAT3 and ALOX15 mRNA, augmented the levels of immune-related factors INF-γ and TGF-ß mRNA, and decreased the levels of IL-17 mRNA thereby indicating that ionizing radiation induced ferroptosis and impairment of intestinal immune function. Liproxstatin-1 is a ferroptosis inhibitor that was found to ameliorate radiation-induced ferroptosis and promote the recovery from immune imbalances. These findings supported the role of ferroptosis in radiation-induced intestinal immune injury and provide novel strategies for protection against radiation injury through regulation of the ferroptosis pathway.


Assuntos
Ferroptose/fisiologia , Intestinos/patologia , Quinoxalinas/farmacologia , Lesões Experimentais por Radiação/prevenção & controle , Radiação Ionizante , Compostos de Espiro/farmacologia , 1-Acilglicerofosfocolina O-Aciltransferase/genética , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Animais , Araquidonato 12-Lipoxigenase/genética , Araquidonato 12-Lipoxigenase/metabolismo , Araquidonato 15-Lipoxigenase/genética , Araquidonato 15-Lipoxigenase/metabolismo , Ferroptose/efeitos dos fármacos , Ferroptose/efeitos da radiação , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/efeitos da radiação , Glutationa/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Intestino Delgado/efeitos da radiação , Intestinos/efeitos dos fármacos , Intestinos/efeitos da radiação , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Mitocôndrias/ultraestrutura , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/metabolismo
9.
Mol Med Rep ; 25(3)2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35039875

RESUMO

The aim of the present study was to explore the mechanism underlying the ultraviolet B (UVB) irradiation­induced apoptosis of human lens epithelial cells (HLECs), and to investigate the protective effect of epigallocatechin gallate (EGCG) against the UVB­induced apoptosis of HLECs. HLECs were exposed to different concentrations of EGCG plus UVB (30 mJ/cm2). Cell viability was determined using the MTT assay. Furthermore, mitochondrial membrane potential (Δψm) and apoptosis were assessed by flow cytometry with JC­1 and Annexin V/PI staining, respectively. Moreover, the activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH­Px), as well as the levels of GSH, hydrogen peroxide (H2O2) and hydroxyl free radicals were determined using biochemical assay techniques. Reverse transcription­quantitative PCR and western blotting were used to detect the mRNA and protein expression levels of Bcl­2, Bax, cytochrome c, caspase­9 and caspase­3, respectively. The results revealed that UVB irradiation reduced the Δψm of HLECs and induced apoptosis. Notably, EGCG significantly attenuated the generation of H2O2 and hydroxyl free radicals caused by UVB irradiation in HLECs, and significantly increased CAT, SOD and GSH­Px activities, however, the GSH levels were not significantly increased. EGCG also reduced UVB­stimulated Bax, cytochrome c, caspase­9 and caspase­3 expression, and elevated Bcl­2 expression, suggesting that EGCG may possess free radical­scavenging properties, thus increasing cell viability. In conclusion, EGCG may be able to protect against UVB­induced HLECs apoptosis through the mitochondria­mediated apoptotic signaling pathway, indicating its potential application in clinical practice.


Assuntos
Catequina/análogos & derivados , Células Epiteliais/efeitos dos fármacos , Cristalino/citologia , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/efeitos da radiação , Western Blotting , Caspases/genética , Caspases/metabolismo , Catalase/metabolismo , Catequina/química , Catequina/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Células Epiteliais/metabolismo , Células Epiteliais/efeitos da radiação , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/efeitos da radiação , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transdução de Sinais/efeitos da radiação , Superóxido Dismutase/metabolismo
10.
Radiat Environ Biophys ; 61(1): 29-36, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34331120

RESUMO

Ionizing radiation has been shown to cause induced genomic instability (IGI), which is defined as a persistently increased rate of genomic damage in the progeny of the exposed cells. In this study, IGI was investigated by exposing human SH-SY5Y neuroblastoma cells to hydroxyurea and zeocin, two chemicals mimicking different DNA-damaging effects of ionizing radiation. The aim was to explore whether IGI was associated with persistent mitochondrial dysfunction. Changes to mitochondrial function were assessed by analyzing mitochondrial superoxide production, mitochondrial membrane potential, and mitochondrial activity. The formation of micronuclei was used to determine immediate genetic damage and IGI. Measurements were performed either immediately, 8 days, or 15 days following exposure. Both hydroxyurea and zeocin increased mitochondrial superoxide production and affected mitochondrial activity immediately after exposure, and mitochondrial membrane potential was affected by zeocin, but no persistent changes in mitochondrial function were observed. IGI became manifested 15 days after exposure in hydroxyurea-exposed cells. In conclusion, immediate responses in mitochondrial function did not cause persistent dysfunction of mitochondria, and this dysfunction was not required for IGI in human neuroblastoma cells.


Assuntos
Neuroblastoma , Superóxidos , Linhagem Celular Tumoral , Instabilidade Genômica , Humanos , Hidroxiureia/farmacologia , Mitocôndrias/efeitos da radiação , Espécies Reativas de Oxigênio , Superóxidos/farmacologia
11.
Meat Sci ; 183: 108646, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34392092

RESUMO

The objective of this study was to investigate if ultrasonication of bovine longissimus thoracis et lumborum (LTL) steaks increases calpain-1 and caspase-3 activities, and if so, to explore the underlying mechanisms that trigger their activation. Post-rigor bovine LTL steaks were subjected to ultrasonication at 40 kHz and 12 W/cm2 for 40 min and subsequently aged for 14 d at 4 °C. Ultrasonication improved beef tenderness (P < 0.05) without negatively impacting pH, color, or cook loss (P > 0.05). Improved tenderness in the ultrasonicated steaks was associated with greater degradation of titin, desmin, troponin-T, and calpastatin and increased calpain-1 autolysis and caspase-3 activity (P < 0.05). In addition, ultrasonicated steaks had greater levels of cytosolic calcium and reactive oxygen species and lower mitochondrial oxygen consumption rate (P < 0.05). These data indicate that improved beef tenderness following ultrasonication is, in part, a function of increased calpain-1 and caspase-3 activities, potentially by elevating cytosolic calcium and inducing mitochondrial dysfunction, respectively.


Assuntos
Calpaína/metabolismo , Caspase 3/metabolismo , Carne Vermelha/análise , Ondas Ultrassônicas , Animais , Cálcio/metabolismo , Bovinos , Masculino , Mitocôndrias/efeitos da radiação , Resistência ao Cisalhamento
12.
PLoS One ; 16(12): e0260968, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34860856

RESUMO

Diabetic retinopathy (DR), the most common complication of diabetes mellitus, is associated with oxidative stress, nuclear factor-κB (NFκB) activation, and excess production of vascular endothelial growth factor (VEGF) and intracellular adhesion molecule-1 (ICAM-1). Muller glial cells, spanning the entirety of the retina, are involved in DR inflammation. Mitigation of DR pathology currently occurs via invasive, frequently ineffective therapies which can cause adverse effects. The application of far-red to near-infrared (NIR) light (630-1000nm) reduces oxidative stress and inflammation in vitro and in vivo. Thus, we hypothesize that 670nm light treatment will diminish oxidative stress preventing downstream inflammatory mechanisms associated with DR initiated by Muller cells. In this study, we used an in vitro model system of rat Müller glial cells grown under normal (5 mM) or high (25 mM) glucose conditions and treated with a 670 nm light emitting diode array (LED) (4.5 J/cm2) or no light (sham) daily. We report that a single 670 nm light treatment diminished reactive oxygen species (ROS) production and preserved mitochondrial integrity in this in vitro model of early DR. Furthermore, treatment for 3 days in culture reduced NFκB activity to levels observed in normal glucose and prevented the subsequent increase in ICAM-1. The ability of 670nm light treatment to prevent early molecular changes in this in vitro high glucose model system suggests light treatment could mitigate early deleterious effects modulating inflammatory signaling and diminishing oxidative stress.


Assuntos
Metabolismo Energético , Células Ependimogliais/efeitos da radiação , Glucose/toxicidade , Raios Infravermelhos , Mitocôndrias/efeitos da radiação , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Células Ependimogliais/efeitos dos fármacos , Células Ependimogliais/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Ratos , Edulcorantes/toxicidade
13.
Cells ; 10(12)2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34944078

RESUMO

Population aging is occurring rapidly worldwide, challenging the global economy and healthcare services. Brain aging is a significant contributor to various age-related neurological and neuropsychological disorders, including Alzheimer's disease and Parkinson's disease. Several extrinsic factors, such as exposure to ionizing radiation, can accelerate senescence. Multiple human and animal studies have reported that exposure to ionizing radiation can have varied effects on organ aging and lead to the prolongation or shortening of life span depending on the radiation dose or dose rate. This paper reviews the effects of radiation on the aging of different types of brain cells, including neurons, microglia, astrocytes, and cerebral endothelial cells. Further, the relevant molecular mechanisms are discussed. Overall, this review highlights how radiation-induced senescence in different cell types may lead to brain aging, which could result in the development of various neurological and neuropsychological disorders. Therefore, treatment targeting radiation-induced oxidative stress and neuroinflammation may prevent radiation-induced brain aging and the neurological and neuropsychological disorders it may cause.


Assuntos
Encéfalo/patologia , Senescência Celular/efeitos da radiação , Radiação Ionizante , Animais , Autofagia/efeitos da radiação , Humanos , Mitocôndrias/patologia , Mitocôndrias/efeitos da radiação , Estresse Oxidativo/efeitos da radiação
14.
Nat Commun ; 12(1): 6399, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34737274

RESUMO

Targeting subcellular organelle with multilevel damage has shown great promise for antitumor therapy. Here, we report a core-shell type of nanoagent with iron (III) carboxylate metal-organic frameworks (MOFs) as shell while upconversion nanoparticles (UCNPs) as core, which enables near-infrared (NIR) light-triggered synergistically reinforced oxidative stress and calcium overload to mitochondria. The folate decoration on MOFs shells enables efficient cellular uptake of nanoagents. Based on the upconversion ability of UCNPs, NIR light mediates Fe3+-to-Fe2+ reduction and simultaneously activates the photoacid generator (pHP) encapsulated in MOFs cavities, which enables release of free Fe2+ and acidification of intracellular microenvironment, respectively. The overexpressed H2O2 in mitochondria, highly reactive Fe2+ and acidic milieu synergistically reinforce Fenton reactions for producing lethal hydroxyl radicals (•OH) while plasma photoacidification inducing calcium influx, leading to mitochondria calcium overload. The dual-mitochondria-damage-based therapeutic potency of the nanoagent has been unequivocally confirmed in cell- and patient-derived tumor xenograft models in vivo.


Assuntos
Cálcio/metabolismo , Estruturas Metalorgânicas/farmacologia , Mitocôndrias/metabolismo , Células HeLa , Humanos , Radical Hidroxila/metabolismo , Raios Infravermelhos , Estruturas Metalorgânicas/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Nanoestruturas/química , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação
15.
Sci Rep ; 11(1): 22872, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34819619

RESUMO

Mitochondrial decline in ageing robs cells of ATP. However, animal studies show that long wavelength exposure (650-900 nm) over weeks partially restores ATP and improves function. The likely mechanism is via long wavelengths reducing nanoscopic interfacial water viscosity around ATP rota pumps, improving their efficiency. Recently, repeated 670 nm exposures have been used on the aged human retina, which has high-energy demands and significant mitochondrial and functional decline, to improve vision. We show here that single 3 min 670 nm exposures, at much lower energies than previously used, are sufficient to significantly improve for 1 week cone mediated colour contrast thresholds (detection) in ageing populations (37-70 years) to levels associated with younger subjects. But light needs to be delivered at specific times. In environments with artificial lighting humans are rarely dark-adapted, hence cone function becomes critical. This intervention, demonstrated to improve aged mitochondrial function can be applied to enhance colour vision in old age.


Assuntos
Trifosfato de Adenosina/metabolismo , Envelhecimento , Percepção de Cores , Visão de Cores , Luz , Mitocôndrias/efeitos da radiação , Células Fotorreceptoras Retinianas Cones/efeitos da radiação , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Estimulação Luminosa , Células Fotorreceptoras Retinianas Cones/metabolismo , Limiar Sensorial , Fatores de Tempo
16.
Exp Cell Res ; 409(2): 112934, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34801561

RESUMO

Hematopoietic stem cells (HSCs) are sensitive to ionizing radiation (IR) damage, and its injury is the primary cause of bone marrow (BM) hematopoietic failure and even death after exposure to a certain dose of IR. However, the underlying mechanisms remain incompletely understood. Here we show that mitochondrial oxidative damage, which is characterized by mitochondrial reactive oxygen species overproduction, mitochondrial membrane potential reduction and mitochondrial permeability transition pore opening, is rapidly induced in both human and mouse HSCs and directly accelerates HSC apoptosis after IR exposure. Mechanistically, 5-lipoxygenase (5-LOX) is induced by IR exposure and contributes to IR-induced mitochondrial oxidative damage through inducing lipid peroxidation. Intriguingly, a natural antioxidant, caffeic acid (CA), can attenuate IR-induced HSC apoptosis through suppressing 5-LOX-mediated mitochondrial oxidative damage, thus protecting against BM hematopoietic failure after IR exposure. These findings uncover a critical role for mitochondria in IR-induced HSC injury and highlight the therapeutic potential of CA in BM hematopoietic failure induced by IR.


Assuntos
Antioxidantes/farmacologia , Araquidonato 5-Lipoxigenase/química , Ácidos Cafeicos/farmacologia , Radioisótopos de Cobalto/toxicidade , Células-Tronco Hematopoéticas/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Dano ao DNA , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Células-Tronco Hematopoéticas/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitocôndrias/efeitos da radiação
17.
Int J Mol Sci ; 22(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34769141

RESUMO

Space is a high-stress environment. One major risk factor for the astronauts when they leave the Earth's magnetic field is exposure to ionizing radiation from galactic cosmic rays (GCR). Several adverse changes occur in mammalian anatomy and physiology in space, including bone loss. In this study, we assessed the effects of simplified GCR exposure on skeletal health in vivo. Three months following exposure to 0.5 Gy total body simulated GCR, blood, bone marrow and tissue were collected from 9 months old male mice. The key findings from our cell and tissue analysis are (1) GCR induced femoral trabecular bone loss in adult mice but had no effect on spinal trabecular bone. (2) GCR increased circulating osteoclast differentiation markers and osteoclast formation but did not alter new bone formation or osteoblast differentiation. (3) Steady-state levels of mitochondrial reactive oxygen species, mitochondrial and non-mitochondrial respiration were increased without any changes in mitochondrial mass in pre-osteoclasts after GCR exposure. (4) Alterations in substrate utilization following GCR exposure in pre-osteoclasts suggested a metabolic rewiring of mitochondria. Taken together, targeting radiation-mediated mitochondrial metabolic reprogramming of osteoclasts could be speculated as a viable therapeutic strategy for space travel induced bone loss.


Assuntos
Osso Esponjoso/efeitos da radiação , Radiação Cósmica/efeitos adversos , Mitocôndrias/efeitos da radiação , Osteoclastos/efeitos da radiação , Osteogênese/efeitos da radiação , Animais , Masculino , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo
18.
Mol Med Rep ; 24(6)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34633055

RESUMO

Thoracic radiotherapy increases the risk of radiation­induced heart damage (RIHD); however, the molecular mechanisms underlying these changes are not fully understood. The aim of the present study was to investigate the effects of radiation on the mouse heart using high­throughput proteomics. Male C57BL/6J mice were used to establish a model of RIHD by exposing the entire heart to 16 Gy high­energy X­rays, and cardiac injuries were verified using a cardiac echocardiogram, as well as by measuring serum brain natriuretic peptide levels and conducting H&E and Masson staining 5 months after irradiation. Proteomics experiments were performed using the heart apex of 5­month irradiated mice and control mice that underwent sham­irradiation. The most significantly differentially expressed proteins were enriched in 'cardiac fibrosis' and 'energy metabolism'. Next, the cardiac fibrosis and changes to energy metabolism were confirmed using immunohistochemistry staining and western blotting. Extracellular matrix proteins, such as collagen type 1 α 1 chain, collagen type III α 1 chain, vimentin and CCCTC­binding factor, along with metabolism­related proteins, such as fatty acid synthase and solute carrier family 25 member 1, exhibited upregulated expression following exposure to ionizing radiation. Additionally, the myocardial mitochondria inner membranes were injured, along with a decrease in ATP levels and the accumulation of lactic acid in the irradiated heart tissues. These results suggest that the high doses of ionizing radiation used lead to structural remodeling, functional injury and fibrotic alterations in the mouse heart. Radiation­induced mitochondrial damage and metabolic alterations of the cardiac tissue may thus be a pathogenic mechanism of RIHD.


Assuntos
Metabolismo Energético/efeitos da radiação , Fibrose/metabolismo , Coração/efeitos da radiação , Animais , Colágeno Tipo III/metabolismo , Fibrose/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Miocárdio/patologia , Proteômica , Raios X/efeitos adversos
19.
Life Sci ; 286: 120051, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34666039

RESUMO

AIMS: To overcome radioresistant cancer cells, clinically relevant radioresistant (CRR) cells were established. To maintain their radioresistance, CRR cells were exposed 2 Gy/day of X-rays daily (maintenance irradiation: MI). To understand whether the radioresistance induced by X-rays was reversible or irreversible, the difference between CRR cells and those without MI for a year (CRR-NoIR cells) was investigated by the mitochondrial function as an index. MAIN METHODS: Radiation sensitivity was determined by modified high density survival assay. Mitochondrial membrane potential (Δψm) was determined by 5,5',6,6'-tetrachloro-1,1', tetraethylbenzimidazolocarbo-cyanine iodide (JC-1) staining. Rapid Glucose-Galactose assay was performed to determine the shift in their energy metabolism from aerobic glycolysis to oxidative phosphorylation in CRR cells. Involvement of prohibitin-1 (PHB1) in Δψm was evaluated by knockdown of PHB1 gene followed by real-time PCR. KEY FINDINGS: CRR cells that exhibited resistant to 2 Gy/day X-ray lost their radioresistance after more than one year of culture without MI for a year. In addition, CRR cells lost their radioresistance when the mitochondria were activated by galactose. Furthermore, Δψm were increased and PHB1 expression was down-regulated, in the process of losing their radioresistance. SIGNIFICANCE: Our finding reveled that tune regulation of mitochondrial function is implicated in radioresistance phenotype of cancer cells. Moreover, as our findings indicate, though further studies are required to clarify the precise mechanisms underlying cancer cell radioresistance, radioresistant cells induced by irradiation and cancer stem cells that are originally radioresistant should be considered separately, the radioresistance of CRR cells is reversible.


Assuntos
Potencial da Membrana Mitocondrial/fisiologia , Membranas Mitocondriais/metabolismo , Tolerância a Radiação/fisiologia , Biomarcadores Farmacológicos , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação , Membranas Mitocondriais/fisiologia , Neoplasias/metabolismo , Células-Tronco Neoplásicas , Tolerância a Radiação/efeitos da radiação , Raios X/efeitos adversos
20.
Int J Mol Sci ; 22(20)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34681703

RESUMO

Until recently, radiation effects have been considered to be mainly due to nuclear DNA damage and their management by repair mechanisms. However, molecular biology studies reveal that the outcomes of exposures to ionizing radiation (IR) highly depend on activation and regulation through other molecular components of organelles that determine cell survival and proliferation capacities. As typical epigenetic-regulated organelles and central power stations of cells, mitochondria play an important pivotal role in those responses. They direct cellular metabolism, energy supply and homeostasis as well as radiation-induced signaling, cell death, and immunological responses. This review is focused on how energy, dose and quality of IR affect mitochondria-dependent epigenetic and functional control at the cellular and tissue level. Low-dose radiation effects on mitochondria appear to be associated with epigenetic and non-targeted effects involved in genomic instability and adaptive responses, whereas high-dose radiation effects (>1 Gy) concern therapeutic effects of radiation and long-term outcomes involving mitochondria-mediated innate and adaptive immune responses. Both effects depend on radiation quality. For example, the increased efficacy of high linear energy transfer particle radiotherapy, e.g., C-ion radiotherapy, relies on the reduction of anastasis, enhanced mitochondria-mediated apoptosis and immunogenic (antitumor) responses.


Assuntos
Epigênese Genética/efeitos da radiação , Mitocôndrias/metabolismo , Radiação Ionizante , Transdução de Sinais/efeitos da radiação , Transição Epitelial-Mesenquimal/efeitos da radiação , Instabilidade Genômica/efeitos da radiação , Humanos , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Dinâmica Mitocondrial/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
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