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1.
J Ethnopharmacol ; 322: 117571, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38103847

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Scoparia dulcis has been identified as a significant ethnopharmacological substance in the Li, Zhuang, and Dai ethnic groups of China. Traditional medicine use S. dulcis to treat numerous illnesses, most notably diabetes. The considerable antidiabetic properties of this herbal remedy have been established by several clinical investigations and animal experiments. The islet is the intended target of S. dulcis, although the cause of its activity and mechanism for diabetes treatment is unclear. The diterpenoids from S. dulcis have been shown in the literature to have significant hypoglycemic efficacy and to protect islet cells in vitro. Diterpenoids may be the components of this herbal remedy that preserve islets, but further research is needed. AIM OF THE STUDY: This study was projected to investigate the new diterpenoid scoparicol E from S. dulcis and examined its islet-protective effect and the potential mechanism both in vitro and in vivo. METHODS: The structure of the novel diterpenoid scoparicol E was clarified by employing a wide range of spectroscopic methods. Using CCK-8 tests, cytotoxicity and antiapoptotic activity of scoparicol E were detected. Serum biochemical analysis and pathologic examination were performed to study the protective effect of scoparicol E against islet damage. The specific mechanism of action of scoparicol E was investigated through the mitochondrial membrane potential, Annexin V-FITC flow cytometry, and western blotting. RESULTS: Scoparicol E reduced MLD-STZ-induced hyperglycemia in mice and increased insulin and islet apoptosis. Scoparicol E effectively suppressed the Bax/Bcl-2/Caspase-3 pathway, according to the in vivo western blot investigation. Scoparicol E showed significant antiapoptotic action in vitro. We also showed that scoparicol E might prevent islet cells from dying by inhibiting the Bax/Bcl-2/Caspase-3 pathway. The Annexin V-FITC flow cytometry results revealed that MIN6 cell apoptosis was considerably decreased following scoparicol E intervention, showing anti-islet cell apoptosis action. Furthermore, the Caspase-3-mediated apoptosis pathway depends on cytochrome c and the potential of the mitochondrial membrane. Scoparicol E prevented the release of cytochrome c, restored the mitochondrial membrane potential, and prevented MIN6 cell apoptosis. CONCLUSION: We demonstrated the new diterpenoid scoparicol E could protect islet cells apoptosis by modulating the Bax/Bcl-2/Caspase-3 pathway.


Assuntos
Diabetes Mellitus , Diterpenos , Ilhotas Pancreáticas , Scoparia , Camundongos , Animais , Caspase 3/metabolismo , Proteína X Associada a bcl-2/metabolismo , Scoparia/metabolismo , Citocromos c/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Apoptose , Diabetes Mellitus/metabolismo , Diterpenos/farmacologia , Diterpenos/metabolismo
2.
Medicina (Kaunas) ; 59(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38138165

RESUMO

Background and Objectives: Cancer is the second-most-important deadly disease in the world, leading to severe socioeconomic consequences and posing a public threat. Consequently, breast and colorectal cancers are significant cancer types that affect women and men more commonly, respectively. Treatment failure or recurrent diseases frequently occur due to resistance, in addition to the side effects of the currently available anticancer agents. Therefore, in this study, herbal melanin anticancer activity was investigated against human breast adenocarcinoma (MDA-MB-231) and human colorectal (HCT 116) cell proliferation and the expression of downregulated anti-apoptotic proteins and upregulated pro-apoptotic p53. Materials and Methods: MDA-MB-231 and HCT 116 cells were monitored for their real-time proliferation properties using Xcelligence. Herbal melanin of various concentrations significantly inhibited MDA-MB-231 and HCT 116 cell proliferation. Then, the expression of proapoptotic and anti-apoptotic proteins such as p53, Bcl-2 and Bcl-xl was studied using Western blotting. Results: The Bcl-2 and Bcl-xl expressions were downregulated, while the p53 expression was upregulated after treatment with herbal melanin. Similarly, the expression of apoptotic proteins such as Bcl-2, Bcl-xl, XIAP, Survivin, Bid, Bax, p53, Cytochrome C, PARP genes and mRNA was studied after herbal melanin treatment using real-time PCR, which revealed the downregulation of Bcl-2, Bcl-xl, XIAP and Survivin and the upregulation of Bid, Bax, p53, Cytochrome C and PARP apoptotic protein expression. Also, caspase 3 and 9 expressions were monitored after the treatment with herbal melanin, which revealed the upregulation of both the MDA-MB-231 and HCT 116 cell types. Conclusions: Overall, herbal melanin can be used as an alternative anticancer agent against the MDA-MB-231 and HCT 116 cell types.


Assuntos
Antineoplásicos , Neoplasias da Mama , Feminino , Humanos , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Proteínas Reguladoras de Apoptose/uso terapêutico , Células HCT116 , Proteína Supressora de Tumor p53/genética , Survivina/metabolismo , Survivina/farmacologia , Survivina/uso terapêutico , Melaninas/metabolismo , Melaninas/farmacologia , Melaninas/uso terapêutico , Apoptose , Proteína X Associada a bcl-2/genética , Citocromos c/metabolismo , Citocromos c/farmacologia , Citocromos c/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proliferação de Células , Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Linhagem Celular Tumoral
3.
Cells ; 12(10)2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37408275

RESUMO

Photobiomodulation (PBM) therapy is a relatively new modality for the combined treatment of cancer. Pre-treatment of certain types of cancer cells with PBM potentiates the treatment efficacy of photodynamic therapy (PDT). The mechanism of action of this synergetic effect is not yet fully understood. In the present study, we focused on protein kinase Cδ (PKCδ) as a proapoptotic agent that is highly expressed in U87MG cells. The distribution of PKCδ in the cytoplasm was changed and its concentration was increased by PBM using radiation at 808 nm (15 mW/cm2, 120 s). This process was accompanied by the organelle specific phosphorylation of PKCδ amino acids (serine/tyrosine). Enhanced phosphorylation of serine 645 in the catalytic domain of PKCδ was found in the cytoplasm, whereas the phosphorylation of tyrosine 311 was mainly localized in the mitochondria. Despite a local increase in the level of oxidative stress, only a small amount of cytochrome c was released from the mitochondria to cytosol. Although a partial inhibition of mitochondrial metabolic activity was induced in PBM-exposed cells, apoptosis was not observed. We hypothesized that PBM-induced photodamage of organelles was neutralized by autophagy maintained in these cells. However, photodynamic therapy may effectively exploit this behaviour to generate apoptosis in cancer treatment, which may increase the treatment efficacy and open up prospects for further applications.


Assuntos
Citocromos c , Terapia com Luz de Baixa Intensidade , Proteína Quinase C-delta , Citocromos c/metabolismo , Mitocôndrias/metabolismo , Proteína Quinase C-delta/metabolismo , Serina/metabolismo , Tirosina/metabolismo , Humanos
4.
Molecules ; 28(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298779

RESUMO

Doxorubicin (DOX) has been extensively utilized in cancer treatment. However, DOX administration has adverse effects, such as cardiac injury. This study intends to analyze the expression of TGF, cytochrome c, and apoptosis on the cardiac histology of rats induced with doxorubicin, since the prevalence of cardiotoxicity remains an unpreventable problem due to a lack of understanding of the mechanism underlying the cardiotoxicity result. Vernonia amygdalina ethanol extract (VAEE) was produced by soaking dried Vernonia amygdalina leaves in ethanol. Rats were randomly divided into seven groups: K- (only given doxorubicin 15 mg/kgbw), KN (water saline), P100, P200, P400, P4600, and P800 (DOX 15 mg/kgbw + 100, 200, 400, 600, and 800 mg/kgbw extract); at the end of the study, rats were scarified, and blood was taken directly from the heart; the heart was then removed. TGF, cytochrome c, and apoptosis were stained using immunohistochemistry, whereas SOD, MDA, and GR concentration were evaluated using an ELISA kit. In conclusion, ethanol extract might protect the cardiotoxicity produced by doxorubicin by significantly reducing the expression of TGF, cytochrome c, and apoptosis in P600 and P800 compared to untreated control K- (p < 0.001). These findings suggest that Vernonia amygdalina may protect cardiac rats by reducing the apoptosis, TGF, and cytochrome c expression while not producing the doxorubicinol as doxorubicin metabolite. In the future, Vernonia amygdalina could be used as herbal preventive therapy for patient administered doxorubicin to reduce the incidence of cardiotoxicity.


Assuntos
Cardiotoxicidade , Vernonia , Ratos , Animais , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Citocromos c/metabolismo , Etanol/efeitos adversos , Fator de Crescimento Transformador beta/metabolismo , Doxorrubicina/efeitos adversos , Apoptose , Extratos Vegetais/farmacologia , Estresse Oxidativo
5.
Chin J Nat Med ; 21(4): 279-291, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37120246

RESUMO

Oxidative stress plays a crucial role in cadmium (Cd)-induced myocardial injury. Mitsugumin 53 (MG53) and its mediated reperfusion injury salvage kinase (RISK) pathway have been demonstrated to be closely related to myocardial oxidative damage. Potentilla anserina L. polysaccharide (PAP) is a polysaccharide with antioxidant capacity, which exerts protective effect on Cd-induced damage. However, it remains unknown whether PAP can prevent and treat Cd-induced cardiomyocyte damages. The present study was desgined to explore the effect of PAP on Cd-induced damage in H9c2 cells based on MG53 and the mediated RISK pathway. For in vitro evaluation, cell viability and apoptosis rate were analyzed by CCK-8 assay and flow cytometry, respectively. Furthermore, oxidative stress was assessed by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining and using superoxide dismutase (SOD), catalase (CAT), and glutathione/oxidized glutathione (GSH/GSSG) kits. The mitochondrial function was measured by JC-10 staining and ATP detection assay. Western blot was performed to detect the expression of proteins related to MG53, the RISK pathway, and apoptosis. The results indicated that Cd increased the levels of reactive oxygen species (ROS) in H9c2 cells. Cd decreased the activities of SOD and CAT and the ratio of GSH/GSSG, resulting in decreases in cell viability and increases in apoptosis. Interestingly, PAP reversed Cd-induced oxidative stress and cell apoptosis. Meanwhile, Cd reduced the expression of MG53 in H9c2 cells and inhibited the RISK pathway, which was mediated by decreasing the ratio of p-AktSer473/Akt, p-GSK3ßSer9/GSK3ß and p-ERK1/2/ERK1/2. In addition, Cd impaired mitochondrial function, which involved a reduction in ATP content and mitochondrial membrane potential (MMP), and an increase in the ratio of Bax/Bcl-2, cytoplasmic cytochrome c/mitochondrial cytochrome c, and Cleaved-Caspase 3/Pro-Caspase 3. Importantly, PAP alleviated Cd-induced MG53 reduction, activated the RISK pathway, and reduced mitochondrial damage. Interestingly, knockdown of MG53 or inhibition of the RISK pathway attenuated the protective effect of PAP in Cd-induced H9c2 cells. In sum, PAP reduces Cd-induced damage in H9c2 cells, which is mediated by increasing MG53 expression and activating the RISK pathway.


Assuntos
Potentilla , Traumatismo por Reperfusão , Cádmio/toxicidade , Cádmio/metabolismo , Caspase 3/metabolismo , Potentilla/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicogênio Sintase Quinase 3 beta/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Citocromos c/metabolismo , Dissulfeto de Glutationa/metabolismo , Dissulfeto de Glutationa/farmacologia , Estresse Oxidativo , Miócitos Cardíacos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Apoptose , Polissacarídeos/farmacologia , Trifosfato de Adenosina/metabolismo
6.
Water Res ; 233: 119778, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36871383

RESUMO

Zerovalent iron [Fe(0)] can donate electron for bioprocess, but microbial uranium (VI) [U(VI)] reduction driven by Fe(0) is still poorly understood. In this study, Fe(0) supported U(VI) bio-reduction was steadily achieved in the 160-d continuous-flow biological column. The maximum removal efficiency and capacity of U(VI) were 100% and 46.4 ± 0.52 g/(m3·d) respectively, and the longevity of Fe(0) increased by 3.09 times. U(VI) was reduced to solid UO2, while Fe(0) was finally oxidized to Fe(III). Autotrophic Thiobacillus achieved U(VI) reduction coupled to Fe(0) oxidation, verified by pure culture. H2 produced from Fe(0) corrosion was consumed by autotrophic Clostridium for U(VI) reduction. The detected residual organic intermediates were biosynthesized with energy released from Fe(0) oxidation and utilized by heterotrophic Desulfomicrobium, Bacillus and Pseudomonas to reduce U(VI). Metagenomic analysis found the upregulated genes for U(VI) reduction (e.g., dsrA and dsrB) and Fe(II) oxidation (e.g., CYC1 and mtrA). These functional genes were also transcriptionally expressed. Cytochrome c and glutathione responsible for electron transfer also contributed to U(VI) reduction. This study reveals the independent and synergistic pathways for Fe(0)-dependent U(VI) bio-reduction, providing promising remediation strategy for U(VI)-polluted aquifers.


Assuntos
Ferro , Urânio , Ferro/metabolismo , Oxirredução , Transporte de Elétrons , Citocromos c/metabolismo
7.
Vet Comp Oncol ; 21(2): 315-326, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36809669

RESUMO

Toosendanin (TSN) is an active compound from the fruit of Melia toosendan Sieb et Zucc. TSN has been shown to have broad-spectrum anti-tumour activities in human cancers. However, there are still many gaps in the knowledge of TSN on canine mammary tumours (CMT). CMT-U27 cells were used to select the optimal acting time and best concentration of TSN to initiate apoptosis. Cell proliferation, cell colony formation, cell migration and cell invasion were analysed. The expression of apoptosis-related genes and proteins were also detected to explore the mechanism of action of TSN. A murine tumour model was established to detect the effect of TSN treatments. The results showed that TSN decreased cell viability of migration and invasion, altered CMT-U27 cell morphology, and inhibited DNA synthesis. TSN-induced cell apoptosis by upregulating BAX, cleaved caspase-3, cleaved caspase-9, p53 and cytochrome C (cytosolic) protein expression, and downregulating Bcl-2 and cytochrome C (mitochondrial) expression. In addition, TSN increased the mRNA transcription levels of cytochrome C, p53 and BAX, and decreased the mRNA expression of Bcl-2. Furthermore, TSN inhibited the growth of CMT xenografts by regulating the expression of genes and proteins activated by the mitochondrial apoptotic pathway. In conclusion, TSN effectively inhibited cell proliferation, migration and invasion activity, as well as induced CMT-U27 cell apoptosis. The study provides a molecular basis for the development of clinical drugs and other therapeutic options.


Assuntos
Doenças do Cão , Medicamentos de Ervas Chinesas , Neoplasias , Humanos , Animais , Cães , Camundongos , Proteína X Associada a bcl-2/metabolismo , Citocromos c/metabolismo , Citocromos c/farmacologia , Proteína Supressora de Tumor p53 , Doenças do Cão/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Apoptose , Neoplasias/tratamento farmacológico , Neoplasias/veterinária , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro , Linhagem Celular Tumoral
8.
Bioorg Chem ; 134: 106341, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36842321

RESUMO

Matrine is a clinically used adjuvant anticancer drug, yet its mild potency limited its application. To improve the anticancer activity of matrine, a total of 31 indole-matrine hybrids were constructed in four rounds of SAR-guided iterative structural optimization process. All of the synthesized compounds were evaluated for their antiproliferative activities against a panel of four human cancer cell lines (Hela, MCF-7, SGC-7901, HepG2) and two normal cell lines (GES-1, LO2). The most active hybrid 8g exhibited the anticancer IC50 values of 0.9 to 1.2 µM, which was 3-magnitude of orders more potent than matrine. 8g also showed better selectivity towards cancer cells with the selectivity index value raised from 1.5 to 6.2. Mechanistic studies demonstrated a mitochondrial distribution for 8g by intracellular click chemistry approaches, which led to the discovery that 8g strongly induced mitochondrial stress, as evidenced by impaired energy metabolism, depolarized mitochondrial membrane potential, overload of mitochondrial calcium and escalated ROS production. 8g-induced mitochondrial stress further led to the release of cytochrome c and subsequent activation of caspase 3, which significantly promoted cellular death and inhibited colony formation.


Assuntos
Antineoplásicos , Caspases , Humanos , Caspases/metabolismo , Citocromos c/metabolismo , Matrinas , Caspase 3/metabolismo , Linhagem Celular Tumoral , Apoptose , Transdução de Sinais , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células , Potencial da Membrana Mitocondrial
9.
Phytomedicine ; 108: 154528, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36343549

RESUMO

BACKGROUND: Anaplastic thyroid cancer (ATC) is one of the fatal cancers and has not effective treatments. Alantolactone (ATL), a terpenoid extracted from traditional Chinese medicinal herb Inula helenium L., confers significant anti-inflammatory, antibacterial and antitumor activity. However, the activity and mechanisms of ATL in ATC remain unclear. PURPOSE: To investigate the potential anti-ATC effects in vitro and in vivo and the mechanisms involved. METHODS: The anti-proliferative activity of Alantolactone (ATL) against ATC cells was analyzed through CCK-8 and colony formation assays. Flow cytometry assay was performed to assess the cell cycle, cell apoptosis, ROS, and mitochondrial membrane potential (ΔΨm), whereas the cellular localization of cytochrome c and calreticulin were determined using cellular immunofluorescence assays. The lactate dehydrogenase (LDH) enzyme activity in the cell culture medium was measured using a commercial LDH kit, whereas ELISA was conducted to assess the secretory function of IL-1ß. Western blot assays were conducted to determine the expression or regulation of proteins associated with apoptosis and pyroptosis. Subcutaneous tumor model of nude mice was established to evaluate the anticancer activity of ATL in vivo. The expression of Ki67, cyclin B1, cleaved-PARP, cleaved-caspase 3, and IL-1ß in the animal tumor tissues was profiled using immunohistochemistry analyses. RESULTS: Our data showed that ATL significantly inhibited the proliferation and colony formation activity of ATC cells. ATL induced ATC cell cycle arrest at G2/M phase, and downregulated the expression of cyclin B1 and CDC2. Furthermore, ATL induced concurrent apoptosis and pyroptosis in the ATC cells, and the cleavage of PARP and GSDME. It also significantly increased the release of LDH and IL-1ß. Mechanically, ATL-mediated increase in ROS suppressed the Bcl-2/Bax ratio, downregulated the mitochondrial membrane potential and increased the release of cytochrome c, leading to caspase 9 and caspase 3 cleavage. We also found that ATL induced the translocation of an immunogenic cell death marker (calreticulin) to the cell membrane. In addition, it inhibited the growth of the ATC subcutaneous xenograft model, and activated proteins associated with apoptosis and pyroptosis, with a high safety profile. CONCLUSION: Taken together, these results firstly demonstrated that ATL exerted an anti-ATC activity by inducing concurrent apoptosis and GSDME-dependent pyroptosis through ROS-mediated mitochondria-dependent caspase activation. Meanwhile, these cell deaths exhibited obvious characteristics of immunogenic cell death, which may synergistically increase the potential of cancer immunotherapy in ATC. Further studies are needed to explore deeper mechanisms for the anti- ATC activity of ATL.


Assuntos
Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Camundongos , Animais , Humanos , Caspase 3/metabolismo , Piroptose , Caspases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Ciclina B1/metabolismo , Calreticulina/metabolismo , Calreticulina/farmacologia , Citocromos c/metabolismo , Camundongos Nus , Carcinoma Anaplásico da Tireoide/tratamento farmacológico , Carcinoma Anaplásico da Tireoide/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Apoptose , Mitocôndrias , Neoplasias da Glândula Tireoide/tratamento farmacológico , Neoplasias da Glândula Tireoide/metabolismo , Linhagem Celular Tumoral
10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 51(5): 563-572, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36581582

RESUMO

OBJECTIVE: To investigate the effect and mechanism of Pinus massoniana needle extracts (PNE) on oxidative stress injury in cerebral ischemia reperfusion rats. METHODS: The SD male rats were randomly divided into sham group, model control group, Edaravone (3 mg/kg) group, PNE low-dose (200 mg/kg), medium-dose (400 mg/kg) and high-dose (800 mg/kg) groups. PNE was administered by gavage for 7 d before modeling and 6 h after modeling in PNE treatment groups; Edaravone was given by intraperitoneal injection 7 d before modeling and 6 h after reperfusion. The rat model of cerebral ischemia reperfusion injury was established by middle cerebral artery occlusion method. After 24 h of reperfusion, the neurological deficit score, brain water content and cerebral infarction volume of rats were measured. The pathological changes of cerebral cortex and hippocampus were observed by HE staining, and the number of normal nerve cells was counted. The apoptosis rate of neurons in cerebral cortex was detected by TUNEL method. The content of nitric oxide (NO), malondialdehyde (MDA) and superoxide dismutase (SOD) activity in ischemic brain tissue were detected. The protein expression of c-Jun N-terminal kinase (JNK) 3, phosphorylated JNK3 (p-JNK3), B-cell lymphoma protein(Bcl) -2, Bcl-2 associated X (Bax), cytochrome C and caspase-3 in cerebral cortex were detected by Western blotting method. RESULTS: Compared with the model control group, the behavioral score, brain water content and cerebral infarction volume in PNE groups were significantly reduced (all P<0.05), the pathological damage of cerebral cortex and hippocampal CA1 area was significantly alleviated, and the number of normal nerve cells in ischemic cortex and hippocampal CA1 area was increased (all P<0.05). The medium-dose PNE group had the best effect. Compared with the model control group, the apoptosis rate of cortical neurons, the content of NO and MDA in cerebral cortex, the ratio of p-JNK3/JNK3, the expression level of cytochrome C and caspase-3 protein in PNE medium-dose group were significantly reduced , and the activity of SOD, the Bcl-2/Bax ratio were significantly improved (all P<0.05). CONCLUSION: PNE ameliorates brain injury after cerebral ischemia reperfusion in rats, which may be related to scavenging NO and MDA, inhibiting oxidative stress-mediated JNK3/caspase-3 signsal transduction to inhibit neuronal apoptosis.


Assuntos
Isquemia Encefálica , Estresse Oxidativo , Extratos Vegetais , Traumatismo por Reperfusão , Animais , Masculino , Ratos , Apoptose , Proteína X Associada a bcl-2/metabolismo , Proteína X Associada a bcl-2/farmacologia , Proteína X Associada a bcl-2/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Caspase 3/metabolismo , Caspase 3/farmacologia , Citocromos c/metabolismo , Citocromos c/farmacologia , Citocromos c/uso terapêutico , Edaravone/farmacologia , Edaravone/uso terapêutico , Infarto da Artéria Cerebral Média , Ratos Sprague-Dawley , Reperfusão , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais , Superóxido Dismutase , Extratos Vegetais/farmacologia , Pinus/química
11.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5564-5573, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36471974

RESUMO

This study observed the effects of ethanol extract of Gastrodiae Rhizoma(GE) on multiple aspects of mitochondrial dysfunction by investigating the mitochondria isolated from rat brains subjected to focal middle cerebral artery occlusion/reperfusion(MCAO/R). SD rats were randomly divided into a sham operation group(Sham), a model group(MCAO/R), low-and high-dose ethanol extract of GE groups(262.3 and 524.6 mg·kg~(-1)), and a nimodipine group(Nim, 15 mg·kg~(-1)). After continuous intragastric administration for 7 days, the MCAO/R model was induced in rats by the suture method. The neurological function and percentage of cerebral infarction volume were measured 24 h after reperfusion, and mitochondrial ultrastructure was observed under an electron microscope. Mitochondria were separated by gradient centrifugation and detected for reactive oxygen species(ROS), malondialdehyde(MDA), respiratory chain enzyme complex Ⅰ-Ⅳ activity, mitochondrial permeability transition pore(mPTP), mitochondrial membrane potential(MMP), and mitochondrial adenosine triphosphate(ATP) content. Enzyme-linked immunosorbent assay(ELISA) was used to detect the expression of cytochrome C(Cyt C) in different sites. TUNEL staining was used to observe the apoptosis of brain tissues in each group, and Western blot was used to detect the expression of B-cell lymphoma 2(Bcl-2) and Bcl-2-associated X protein(Bax) in brain tissues. The experimental results revealed that compared with the Sham group, the MCAO/R group showed evident neurological dysfunction and cerebral infarction(P<0.01) accompanied by mitochondrial swelling and crest disappearance, increased ROS level and MDA content, inhibited activity of respiratory chain enzyme complex Ⅰ-Ⅳ, abnormal opening of mPTP, and reduced MMP and mitochondrial ATP(P<0.01). Besides, many Cyt C was released from mitochondria into the cytoplasm to induce apoptosis(P<0.01). The ethanol extract of GE positively affected the behavior deficit and mitochondrial health of MCAO/R rats, with the manifestations of decreased production of ROS and MDA(P<0.01), potentiated activity of mitochondrial respiratory chain enzyme complex Ⅰ-Ⅳ, and restored the level of mPTP(P<0.05). In addition, the ethanol extract of GE reduced the loss of MMP and the escape of Cyt C to the cytoplasm(P<0.05), reduced the number of TUNEL positive cells(P<0.01) accompanied by the decrease in Bax and the up-regulation of Bcl-2(P<0.01), and increased the level of ATP(P<0.01). In conclusion, GE ethanol extract has a protective effect against MCAO/R-induced mitochondrial dysfunction, and the mechanism may be related to the regulation of oxidative stress, maintenance of functional morphology of mitochondria, and inhibition of endogenous apoptosis.


Assuntos
Fármacos Neuroprotetores , Traumatismo por Reperfusão , Animais , Ratos , Trifosfato de Adenosina/farmacologia , Apoptose , Proteína X Associada a bcl-2/metabolismo , Citocromos c/metabolismo , Etanol , Infarto da Artéria Cerebral Média , Mitocôndrias , Fármacos Neuroprotetores/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Poro de Transição de Permeabilidade Mitocondrial
12.
Molecules ; 27(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36296460

RESUMO

Rubus fairholmianus (RF) has widely been used to treat various ailments, including pain, diabetes, and cancer. Zinc oxide nanoparticles (ZnO NPs) have drawn attention in modern healthcare applications. Hence, we designed this study to synthesize zinc oxide (ZnO) nanoparticles using R. fairholmianus root extract to investigate its synergistic cytotoxic effect on MCF-7 cells and explore the possible cell death mechanism. ZnO NPs were synthesized via green synthesis using R. fairholmianus root extract, and the effect on MCF-7 cells was determined by looking at cellular morphology, proliferation, cytotoxicity, apoptosis, and reactive oxygen species (ROS). The results showed that cellular proliferation was reduced following treatment with R. fairholmianus capped zinc oxide nanoparticles (RFZnO NPs), while cytotoxicity and ROS were increased. There was also an increase in apoptosis as indicated by the significant increase in cytoplasmic cytochrome c and caspase 3/7 (markers of apoptosis), as well as increased levels of pro-apoptotic proteins (p53, Bax) and decreased levels of anti-apoptotic protein (Bcl-2). In conclusion, these results showed that RFZnO NPs induce apoptosis in breast cancer cells via a mitochondria-mediated caspase-dependent apoptotic pathway and suggest the use of acetone root extract of R. fairholmianus for the treatment of cancer-related ailments.


Assuntos
Neoplasias da Mama , Nanopartículas Metálicas , Nanopartículas , Rubus , Óxido de Zinco , Humanos , Feminino , Óxido de Zinco/farmacologia , Óxido de Zinco/metabolismo , Células MCF-7 , Rubus/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Caspase 3/metabolismo , Neoplasias da Mama/tratamento farmacológico , Citocromos c/metabolismo , Proteína X Associada a bcl-2/metabolismo , Proteína Supressora de Tumor p53 , Acetona , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Extratos Vegetais/farmacologia
13.
Toxicol Appl Pharmacol ; 454: 116215, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36067808

RESUMO

Breast cancer is a fatal cancer with the highest mortality in female. New strategies for anti-breast cancer are still urgently needed. Catalpol, an iridoid glycoside extracted from the traditional Chinese medicinal plant Rehmannia glutinosa, has shown anticancer efficacy in various cancer cells. However, its effect on breast cancer remains unclear. In this study, we aim to investigate the anti-breast cancer activity of catalpol and elucidate its underlying mechanism. Cell counting kit-8 (CCK-8) and morphology change showed that catalpol could inhibit the proliferation and viability of MCF-7 cells. Catalpol administration reduced the tumor volume in xenograft model. Catalpol induced apoptosis in MCF-7 cells confirmed by Hoechst 33342 staining and Annexin V-FITC/PI double staining. In vivo, catalpol also induced apoptosis as seen from the increased level of terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) in tumor. According to JC-1 and Dichlorodi-hydrofluorescein Diacetate (DCFH-DA) staining, loss of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) generation was found in MCF-7 cells treated with catalpol. Furthermore, catalpol also increased the level of cytoplasmic cytochrome c and activity of caspase-3 in MCF-7 cells. Likewise, histopathological and immunohistochemical (IHC) assay also found that catalpol enhanced the levels of cytochrome c and caspase-3 in breast cancer tissues. Ultimately, acetylation, 2-hydroxyisobutyrylation and lactylation were dramatically increased, whereas succinylation, malonylation and phosphorylation were markedly decreased in the breast cancer tumor treated with catalpol. Taken together, catalpol inhibited breast cancer in vitro and in vivo through induction of apoptosis via mitochondria apoptosis pathway and regulation of protein post-translational modifications (PTMs). Thus, it can be considered as an excellent candidate compound for treatment of breast cancer.


Assuntos
Neoplasias da Mama , Citocromos c , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Caspase 3/metabolismo , Citocromos c/metabolismo , Feminino , Humanos , Glucosídeos Iridoides/farmacologia , Glucosídeos Iridoides/uso terapêutico , Mitocôndrias , Processamento de Proteína Pós-Traducional , Espécies Reativas de Oxigênio/metabolismo
14.
Ecotoxicol Environ Saf ; 244: 114081, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36113268

RESUMO

Excessive use of hard-to-degrade pesticides threatens the ecological health of aquatic systems. This study aimed to investigate difenoconazole (DFZ) residues in the environment induced neurotoxicity in carp and the underlying mechanisms. A total of thirty-six carps were divided into three groups and exposed to 0, 0.5, and 2.0 mg/L DFZ for 96 h, respectively. The alterations in behavior and blood-brain barrier (BBB) were examined, and potential mechanisms were explored using immunological assays and biochemical methods. The results showed that DFZ exposure caused behavioral freezing, reduced feeding, and neuronal necrosis in carp. Mechanistically, DFZ triggered ROS accumulation and destroyed the balance between oxidation and antioxidation with increased lipid peroxidation product MDA contents and reduced antioxidant enzymes SOD and CAT activities in the carp brain by inhibiting the NF-E2-related factor 2 (Nrf2) pathway. The activation of oxidative stress further reduced tight junction proteins and MMP levels, thereby destroying BBB and leading to DFZ leakage into the brain. Increased BBB permeability additionally led to DFZ activation of nuclear factor kappa-B signaling-mediated inflammatory cytokine storm, exacerbating neuroinflammation. Meanwhile, DFZ exposure activated mitochondria-associated apoptosis in the carp's brain by up-regulating Bcl-2 associated X protein, cleaved-caspase3, and cytochrome C and decreasing B-cell lymphoma-2 levels. Interestingly, the carp's brain initiated a protective autophagic response via the PI3K/AKT/TOR pathway intending to counteract the neurotoxicity of DFZ. Overall, we concluded that accumulation of DFZ at high concentrations in the aquatic systems disrupted the BBB and resulted in neurotoxicity in carp through inhibition of Nrf2 pathway-mediated ROS accumulation. This study provides a reference for monitoring DFZ residues in the environment and a new target for the treatment of DFZ-induced neurotoxicity in carp.


Assuntos
Carpas , Praguicidas , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Barreira Hematoencefálica/metabolismo , Carpas/metabolismo , Citocromos c/metabolismo , Dieta , Suplementos Nutricionais/análise , Dioxolanos , Proteínas de Peixes/metabolismo , Imunidade Inata , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo , Proteínas de Junções Íntimas/metabolismo , Triazóis
15.
Poult Sci ; 101(10): 102072, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055020

RESUMO

The main objective of this study was to explore the effects of dietary selenium yeast and jujube powder on mitochondrial oxidative damage and cell apoptosis of broilers during postmortem aging, chicken breasts of broilers fed diets supplemented with different concentrations of selenium yeast and jujube powder were used as research subjects. With the prolongation of postmortem aging time, the levels of reactive oxygen species (ROS), carbonyl content, mitochondrial permeability transition pore (MPTP) openness, and mitochondrial membrane permeability increased significantly (P < 0.05). The contents of the sulfhydryl, mitochondrial membrane potential, shear force, and cytochrome C (Cyt-c) reduction level decreased significantly (P < 0.05). The activity of Caspase-3 and Caspase-9 increased from 0 to 24 h postmortem but fell from 24 to 72 h postmortem. Compared with the control group, dietary selenium yeast and jujube powder significantly reduced mitochondrial oxidative damage. They greatly increased the shear force, mitochondrial membrane potential, and Cyt-c reduction levels (P < 0.05). Among them, the combination group of high-dose selenium yeast and jujube powder had more significant effects on ROS scavenging, reducing cell membrane permeability, protecting cell membrane integrity, and increasing Cyt-c reduction level (P < 0.05). In conclusion, cell apoptosis intensifies during the chicken breast's aging time, and muscle tenderness continues. Still, different doses of dietary selenium yeast and jujube powder can inhibit mitochondrial oxidation to various degrees. The combined group of selenium yeast and jujube powder with 0.6 mg·kg-1 has the best effect. This study is of great significance for applying natural antioxidant ingredients such as selenium yeast and jujube powder in the development and utilization of poultry feed.


Assuntos
Selênio , Ziziphus , Animais , Antioxidantes/metabolismo , Apoptose , Caspase 3/metabolismo , Caspase 9/metabolismo , Caspase 9/farmacologia , Galinhas , Citocromos c/metabolismo , Citocromos c/farmacologia , Suplementos Nutricionais , Poro de Transição de Permeabilidade Mitocondrial , Estresse Oxidativo , Pós/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/metabolismo , Selênio/metabolismo , Selênio/farmacologia , Ziziphus/metabolismo
16.
Aging (Albany NY) ; 14(17): 7109-7125, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36098742

RESUMO

Acute promyelocytic leukemia (APL) is a specific subtype of acute myelogenous leukemia (AML) characterized by the proliferation of abnormal promyelocytes. Realgar, a Chinese medicine containing arsenic, can be taken orally. Traditional Chinese medicine physicians have employed realgar to treat APL for over a thousand years. Therefore, realgar may be a promising candidate for the treatment of APL. Nevertheless, the underlying mechanism behind realgar therapy is largely unclear. The present study aimed to investigate the effect of realgar on cell death in the APL cell line (NB4) in vitro and to elucidate the underlying mechanism. In this study, after APL cells were treated with different concentrations of realgar, the cell survival rate, apoptotic assay, morphological changes, ATP levels and cell cycle arrest were assessed. The expression of Bcl-2, Bax, Cytochrome C (Cyt-C) and apoptosis-inducing factor (AIF) at the mRNA and protein levels were also measured by immunofluorescence, quantitative PCR (qPCR) and Western blotting. We found that realgar could significantly inhibit APL cell proliferation and cell death in a time- and dose-dependent manner. Realgar effectively decreased the ATP levels in APL cells. Realgar also induced APL cell cycle arrest at the S and G2/M phases. Following realgar treatment, the mRNA and protein levels of Bcl-2 were significantly downregulated, whereas the levels of Bax, Cyt-C, and AIF were significantly upregulated. In summary, realgar can induce APL cell death via the Bcl-2/Bax/Cyt-C/AIF signaling pathway, suggesting that realgar may be an effective therapeutic for APL.


Assuntos
Arsênio , Leucemia Promielocítica Aguda , Trifosfato de Adenosina , Apoptose , Fator de Indução de Apoptose/metabolismo , Arsênio/metabolismo , Arsênio/farmacologia , Arsênio/uso terapêutico , Arsenicais , Morte Celular , Linhagem Celular Tumoral , Citocromos c/metabolismo , Citocromos c/farmacologia , Citocromos c/uso terapêutico , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Medicina Tradicional Chinesa , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro , Transdução de Sinais , Sulfetos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
17.
Osteoarthritis Cartilage ; 30(12): 1606-1615, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096467

RESUMO

OBJECTIVE: To explore the association between oxidative stress (OS) and Kashin-Beck disease (KBD). METHODS: Terms associated with "KBD" and "OS" were searched in the six different databases up to October 2021. Stata 14.0 was used to pool the means and standard deviations using random-effect or fixed-effect model. The differentially expressed genes in the articular chondrocytes of KBD were identified, the OS related genes were identified by blasting with the GeneCards. The KEGG pathway and gene ontology enrichment analysis was conducted using STRING. RESULTS: The pooled SMD and 95% CI showed hair selenium (-4.59; -6.99, -2.19), blood selenium (-1.65; -2.86, -0.44) and glutathione peroxidases (-4.15; -6.97, -1.33) levels were decreased in KBD, whereas the malondialdehyde (1.12; 0.60, 1.64), nitric oxide (2.29; 1.31, 3.27), nitric oxide synthase (1.07; 0.81, 1.33) and inducible nitric oxide synthase (1.69; 0.62, 2.77) were increased compared with external controls. Meanwhile, hair selenium (-2.71; -5.32, -0.10) and glutathione peroxidases (-1.00; -1.78, -0.22) in KBD were decreased, whereas the malondialdehyde (1.42; 1.04, 1.80), nitric oxide (3.08; 1.93, 4.22) and inducible nitric oxide synthase (0.81; 0.00, 1.61) were elevated compared with internal controls. Enrichment analysis revealed apoptosis was significantly correlated with KBD. The significant biological processes revealed OS induced the release of cytochrome c from mitochondria. The cellular component of OS located in the mitochondrial outer membrane. CONCLUSIONS: The OS levels in KBD were significantly increased because of selenium deficiency, OS mainly occurred in mitochondrial outer membrane, released of cytochrome c from mitochondria, and induced apoptotic signaling pathway.


Assuntos
Doença de Kashin-Bek , Selênio , Humanos , Doença de Kashin-Bek/genética , Doença de Kashin-Bek/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Selênio/metabolismo , Biologia Computacional , Óxido Nítrico/metabolismo , Citocromos c/metabolismo , Citocromos c/farmacologia , Estresse Oxidativo , Malondialdeído/farmacologia , Glutationa/metabolismo , Glutationa/farmacologia , Peroxidases/metabolismo , Peroxidases/farmacologia
18.
J Ethnopharmacol ; 299: 115621, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-35987413

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lignosus rhinocerus, also known as Tiger Milk Mushroom has been used traditionally to treat a variety of human conditions, including asthma, diabetes, respiratory disease, skin allergy, and food poisoning. The reported activities of Lignosus rhinocerus extracts include anti-inflammatory, anti-oxidant, anti-asthmatic, anti-microbial, anti-cancer, neuroprotection, and immune modulation effects. However, its effect on human skin is not well documented, including human skin exposed to ultraviolet light (UV). Exposure to UV can trigger various cellular responses, including inflammation, oxidative stress, DNA damage, cell death, and cellular aging. AIM OF THE STUDY: The study aims to investigate the effects of methanolic extract prepared from cultured Lignosus rhinocerus (herein referred to as TM02 and its methanol extract as TM02-ME) on UV-irradiated human keratinocytes. MATERIALS AND METHODS: Powdered stock of TM02 was dissolved and sequentially extracted with different solvents to prepare the extracts and the methanol extract was subsequently characterized based on its bio-activities on HaCaT human keratinocytes. The keratinocytes were pre-treated with the methanol extract followed by UV-irradiation. Cellular responses of the HaCaT cells such as cell viability, DNA damage, as well as gene and protein expressions that were responsive to the treatments, were characterized by using bio-assays, including reverse-transcription based PCR, Western blot, cell viability, and mitochondrial Cytochrome C release assays. RESULTS: TM02-ME protected HaCaT cells from UV-induced DNA damage and cell death in a dose-dependent manner. Pre-treatment of HaCaT cells with TM02-ME led to a 39% reduction of cyclobutane pyrimidine dimers (CPD) and up-regulated the gene expression of REV1 and SPINK5 in UVB-irradiated HaCaT cells when compared to the control. In addition, TM-02-ME treated HaCaT cells increased the expression of BCL-XL and BCL-2 proteins which coincided with the down-regulation of mitochondrial Cyt. C release in the UV-B irradiated HaCaT cells. The results were further supported by data that showed the stable clones of HaCaT cells stably expressed BCL-XL were resistant to UVB-induced cell death. CONCLUSIONS: __The results showed that TM02-ME confers photoprotective activities to UVB-irradiated HaCaT cells, leading to a reduction in DNA damage and cell death as well as up-regulated the expression of REV1 and SPINK5 which are involved in DNA repair and skin barrier function, respectively. The up-regulation of pro-survival members of the BCL-2 family by TM02-ME confers protection against UVB-induced cell death.


Assuntos
Antiasmáticos , Raios Ultravioleta , Antiasmáticos/farmacologia , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Citocromos c/metabolismo , Humanos , Queratinócitos , Metanol/farmacologia , Polyporaceae , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Dímeros de Pirimidina/metabolismo , Dímeros de Pirimidina/farmacologia , Solventes/farmacologia , Raios Ultravioleta/efeitos adversos
19.
Metab Syndr Relat Disord ; 20(8): 473-479, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35796694

RESUMO

Background: Hyperuricemia (HU) is a metabolic disease characterized by high uric acid levels in the blood. HU is a risk factor for diabetes, cardiovascular complications, metabolic syndrome, and chronic kidney disease. Purpose: The present study was performed to determine the effect of experimental HU on xanthine oxidase (XO), tumor necrosis factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), interleukin-17 (IL-17), cytochrome C, glutathione peroxidase (GPx), caspase-3, and 8-hydroxydeoxyguanosine (8-OHdG) levels in liver tissues of rats. Study Design: Thirty-five, male, Wistar albino-type rats were used for this study. Experimental groups were formed as follows: Group 1: control group; Group 2: potassium oxonate (PO) group; group 3: PO+NAR (naringenin; 2 weeks) group; and Group 4: PO (2 weeks)+NAR (2 weeks) group (total of 4 weeks). Methods: The first group was not given anything other than normal rat food and drinking water. In the second group, a 250 mg/kg intraperitoneal dose of PO was administered for 2 weeks. In the third group, 250 mg/kg intraperitoneal PO (application for 2 weeks) and 100 mg/kg NAR intraperitoneally 1 hr after each application were administered. In the fourth group, intraperitoneal PO administration was applied for 2 weeks, followed by intraperitoneal administration of NAR for 2 weeks (4 weeks in total). At the end of the experimental period, XO, TNF-α, NF-κB, IL-17, cytochrome C, GPx, caspase-3, and 8-OHdG levels were determined in liver tissues. Results: HU increased XO, TNF-α, NF-κB, IL-17, cytochrome C, caspase-3, and 8-OHdG levels in liver tissues. However, both 2 and 4 weeks of NAR supplementation decreased these values, and also NAR supplementation led to an increase in GPx levels in tissues. Conclusions: The results of the study show that increased inflammation, apoptosis, and DNA damage in experimental HU can be prevented by administration of NAR due to inhibition of cytochrome C, NF-κB, caspase-3, and 8-OHdG.


Assuntos
Água Potável , Hiperuricemia , Masculino , Ratos , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , NF-kappa B/farmacologia , Caspase 3/genética , Caspase 3/metabolismo , Caspase 3/farmacologia , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Citocromos c/genética , Citocromos c/metabolismo , Citocromos c/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Xantina Oxidase/genética , Xantina Oxidase/metabolismo , Xantina Oxidase/farmacologia , Ácido Úrico , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/farmacologia , Água Potável/efeitos adversos , Água Potável/metabolismo , Ratos Wistar , Apoptose , Inflamação/metabolismo , Fígado/metabolismo , Dano ao DNA
20.
Arch Biochem Biophys ; 726: 109232, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35660297

RESUMO

Much evidence indicates that superoxide is generated from O2 in a cyanide-sensitive reaction involving a reduced component of complex III of the mitochondrial respiratory chain, particularly when antimycin A is present. Although it is generally believed that ubisemiquinone is the electron donor to O2, little experimental evidence supporting this view has been reported. Experiments with succinate as electron donor in the presence of antimycin A in intact rat heart mitochondria, which contain much superoxide dismutase but little catalase, showed that myxothiazol, which inhibits reduction of the Rieske iron-sulfur center, prevented formation of hydrogen peroxide, determined spectrophotometrically as the H2O2-peroxidase complex. Similarly, depletion of the mitochondria of their cytochrome c also inhibited formation of H2O2, which was restored by addition of cytochrome c. These observations indicate that factors preventing the formation of ubisemiquinone also prevent H2O2 formation. They also exclude ubiquinol, which remains reduced under these conditions, as the reductant of O2. Since cytochrome b also remains fully reduced when myxothiazol is added to succinate- and antimycin A-supplemented mitochondria, reduced cytochrome b may also be excluded as the reductant of O2. These observations, which are consistent with the Q-cycle reactions, by exclusion of other possibilities leave ubisemiquinone as the only reduced electron carrier in complex III capable of reducing O2 to O2-.


Assuntos
Mitocôndrias Cardíacas , Superóxidos , Animais , Antimicina A/metabolismo , Antimicina A/farmacologia , Citocromos b/metabolismo , Citocromos c/metabolismo , Transporte de Elétrons , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Elétrons , Peróxido de Hidrogênio/metabolismo , Mitocôndrias Cardíacas/metabolismo , Oxirredução , Ratos , Substâncias Redutoras/metabolismo , Succinatos/metabolismo , Succinatos/farmacologia , Ácido Succínico , Superóxidos/metabolismo , Ubiquinona/análogos & derivados
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