RESUMO
Cutaneous bacterial wound infections typically involve gram-positive cocci such as Staphylococcus aureus (SA) and usually become biofilm infections. Bacteria in biofilms may be 100-1000-fold more resistant to an antibiotic than the clinical laboratory minimal inhibitory concentration (MIC) for that antibiotic, contributing to antimicrobial resistance (AMR). AMR is a growing global threat to humanity. One pathogen-antibiotic resistant combination, methicillin-resistant SA (MRSA) caused more deaths globally than any other such combination in a recent worldwide statistical review. Many wound infections are accessible to light. Antimicrobial phototherapy, and particularly antimicrobial blue light therapy (aBL) is an innovative non-antibiotic approach often overlooked as a possible alternative or adjunctive therapy to reduce antibiotic use. We therefore focused on aBL treatment of biofilm infections, especially MRSA, focusing on in vitro and ex vivo porcine skin models of bacterial biofilm infections. Since aBL is microbicidal through the generation of reactive oxygen species (ROS), we hypothesized that menadione (Vitamin K3), a multifunctional ROS generator, might enhance aBL. Our studies suggest that menadione can synergize with aBL to increase both ROS and microbicidal effects, acting as a photosensitizer as well as an ROS recycler in the treatment of biofilm infections. Vitamin K3/menadione has been given orally and intravenously worldwide to thousands of patients. We conclude that menadione/Vitamin K3 can be used as an adjunct to antimicrobial blue light therapy, increasing the effectiveness of this modality in the treatment of biofilm infections, thereby presenting a potential alternative to antibiotic therapy, to which biofilm infections are so resistant.
Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Infecção dos Ferimentos , Humanos , Vitamina K 3/farmacologia , Vitamina K 3/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Biofilmes , Infecções Estafilocócicas/tratamento farmacológico , Testes de Sensibilidade MicrobianaRESUMO
Rhythms in the pseudo-steady state (PSS) levels of reactive species (RS), particularly superoxide and hydroxyl radicals, exist in cancer cells. The RS rhythm characteristics, particularly frequency and amplitude, are entrained (reset) by the anticancer compounds/drugs. In this work, we show for the first time that the phase of the RS rhythm at which the drug is added is significantly important in determining the cytotoxicity of anticancer compounds/drugs such as menadione and curcumin, in two different cancer cell lines. Curcumin, the more effective of the two drugs (IC50 = 15 µM, SiHa; 6 µM, HCT116) induced reset of superoxide and hydroxyl rhythms from 15.4 h to 9 h, and 25 h to 11 h respectively, as well as caused increases in these radical levels. However, menadione (IC50 = 20 µM, SiHa; 17 µM, HCT116) affected only the superoxide levels. Drug treatment at different time points/phase of the RS rhythm resulted in a maximum of 27% increase in cytotoxicity, which is significant. Further, we report for the first time, an unexpected absence of a correlation between the intracellular PSS RS and antioxidant levels; thus, the practice of using antioxidant enzyme levels as surrogate markers of intracellular oxidative stress levels may need a re-consideration. Therefore, the RS rhythm could be a fundamental/generic target to manipulate for improved cancer therapy.
Assuntos
Antineoplásicos/uso terapêutico , Curcumina/uso terapêutico , Neoplasias/tratamento farmacológico , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Vitamina K 3/uso terapêutico , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Células HCT116 , Humanos , Radical Hidroxila/metabolismo , Neoplasias/metabolismo , Superóxidos/metabolismoRESUMO
BACKGROUND: 1,4-naphthoquinones, especially juglone, are known for their anticancer activity. However, plumbagin, lawsone, and menadione have been less investigated for these properties. Therefore, we aimed to determine the effects of plumbagin, lawsone, and menadione on C6 glioblastoma cell viability, ROS production, and mitochondrial function. METHODS: Cell viability was assessed spectrophotometrically using metabolic activity method, and by fluorescent Hoechst/propidium iodide nuclear staining. ROS generation was measured fluorometrically using DCFH-DA. Oxygen uptake rates were recorded by the high-resolution respirometer Oxygraph-2k. RESULTS: Plumbagin and menadione displayed highly cytotoxic activity on C6 cells (IC50 is 7.7 ± 0.28 µM and 9.6 ± 0.75 µM, respectively) and caused cell death by necrosis. Additionally, they increased the amount of intracellular ROS in a concentration-dependent manner. Moreover, even at very small concentrations (1-3 µM), these compounds significantly uncoupled mitochondrial oxidation from phosphorylation impairing energy production in cells. Lawsone had significantly lower viability decreasing and mitochondria-uncoupling effect, and exerted strong antioxidant activity. CONCLUSIONS: Plumbagin and menadione exhibit strong prooxidant, mitochondrial oxidative phosphorylation uncoupling and cytotoxic activity. In contrast, lawsone demonstrates a moderate effect on C6 cell viability and mitochondrial functions, and possesses strong antioxidant properties.
Assuntos
Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Glioblastoma/metabolismo , Mitocôndrias/efeitos dos fármacos , Naftoquinonas/farmacologia , Oxidantes/farmacologia , Desacopladores/farmacologia , Animais , Antineoplásicos/uso terapêutico , Antioxidantes/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Glioblastoma/tratamento farmacológico , Mitocôndrias/metabolismo , Naftoquinonas/uso terapêutico , Oxidantes/uso terapêutico , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Espécies Reativas de Oxigênio/metabolismo , Desacopladores/uso terapêutico , Vitamina K 3/farmacologia , Vitamina K 3/uso terapêuticoRESUMO
INTRODUCTION: Smokers have a significantly decreased risk of pre-eclampsia (PE), possibly attributed to an increase in blood carbon monoxide (CO) concentrations. At physiological concentrations, CO has been demonstrated to have placental vasodilatory and anti-inflammatory properties. Increasing endogenous CO production may have therapeutic potential to either prevent or treat PE. Menadione (MD), synthetic vitamin K3, increases CO in rat microsomes. Our objective was to investigate MD's ability to increase endogenous CO concentrations in pregnancy. METHODS: Three experiments were completed. First, in vitro CO production was measured using isolated GD15 placentas. Second, non-pregnant normotensive mice received no, 1.5, 4.0 or 6.5â¯g/L MD for 7 days. Lastly, pregnant normotensive mice received either no or 6.5â¯g/L MD in water from GD10.5 to GD17.5. Consumption was measured as average daily water intake per gram of body weight. Maternal and fetal CO levels in the blood and tissue were quantified using headspace gas chromatography. RESULTS: MD significantly increased CO production in isolated GD15 placentas. In both pregnant and non-pregnant experiments, splenic CO, hepatic CO, and splenic mass were higher in treated mice compared to controls (all pâ¯<â¯0.05). Maternal %COHb and Hb in treated dams were not significantly different compared to controls. The fetal:placental mass ratio was significantly lower in the treatment group (pâ¯=â¯0.002). DISCUSSION: Placental CO production was observed in GD15 placentas after co-incubation with MD. MD administration increased CO in the liver and spleens of pregnant mice. Further investigation into different doses of MD is required to identify one without demonstrable fetal/placental effects.
Assuntos
Monóxido de Carbono/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/prevenção & controle , Vitamina K 3/uso terapêutico , Vitaminas/uso terapêutico , Animais , Avaliação Pré-Clínica de Medicamentos , Feminino , Camundongos , Placenta/efeitos dos fármacos , Gravidez , Resultado da Gravidez , Vitamina K 3/farmacologia , Vitaminas/farmacologiaRESUMO
OBJECTIVE: To determine if injection of vitamin K3 in an acupuncture point is optimal for the treatment of primary dysmenorrhoea, when compared with 2 other injection treatments. SETTING: A Menstrual Disorder Centre at a public hospital in Shanghai, China. PARTICIPANTS: Chinese women aged 14-25 years with severe primary dysmenorrhoea for at least 6 months not relieved by any other treatment were recruited. Exclusion criteria were the use of oral contraceptives, intrauterine devices or anticoagulant drugs, pregnancy, history of abdominal surgery, participation in other therapies for pain and diagnosis of secondary dysmenorrhoea. Eighty patients with primary dysmenorrhoea, as defined on a 4-grade scale, completed the study. Two patients withdrew after randomisation. INTERVENTIONS: A double-blind, double-dummy, randomised controlled trial compared vitamin K3 acupuncture point injection to saline acupuncture point injection and vitamin K3 deep muscle injection. Patients in each group received 3 injections at a single treatment visit. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the difference in subjective perception of pain as measured by an 11 unit Numeric Rating Scale (NRS). Secondary measurements were Cox Pain Intensity and Duration scales and the consumption of analgesic tablets before and after treatment and during 6 following cycles. RESULTS: Patients in all 3 groups experienced pain relief from the injection treatments. Differences in NRS measured mean pain scores between the 2 active control groups were less than 1 unit (-0.71, CI -1.37 to -0.05) and not significant, but the differences in average scores between the treatment hypothesised to be optimal and both active control groups (1.11, CI 0.45 to 1.78) and (1.82, CI 1.45 to 2.49) were statistically significant in adjusted mixed-effects models. Menstrual distress and use of analgesics were diminished for 6 months post-treatment. CONCLUSIONS: Acupuncture point injection of vitamin K3 relieves menstrual pain rapidly and is a useful treatment in an urban outpatient clinic. TRIAL REGISTRATION NUMBER: NCT00104546; Results.
Assuntos
Pontos de Acupuntura , Terapia por Acupuntura/métodos , Dismenorreia/terapia , Manejo da Dor , Dor/tratamento farmacológico , Vitamina K 3/uso terapêutico , Vitaminas/uso terapêutico , Adolescente , Adulto , China , Método Duplo-Cego , Dismenorreia/tratamento farmacológico , Feminino , Humanos , Injeções , Gravidez , Vitamina K 3/administração & dosagem , Vitaminas/administração & dosagem , Adulto JovemRESUMO
OBJECTIVE: Bipolar disorder places a significant burden on individuals, caregivers and family, and the broader community. Current treatments are believed to be more effective against manic symptoms, leaving a shortfall in recovery during the depressive phase of the illness. The current study draws on recent evidence suggesting that, in addition to increased oxidative load, alterations in mitochondrial function occur in bipolar disorder. METHODS: This 16-week study aims to explore the potential benefits of N-acetylcysteine (NAC) alone or in combination (CT) with selected nutraceuticals believed to enhance mitochondrial function. The study includes adults diagnosed with bipolar disorder currently experiencing an episode of depression. Participants are asked to take NAC, CT, or placebo in addition to any usual treatments. A post-discontinuation visit is conducted 4 weeks following the treatment phase. RESULTS: The primary outcome of the study will be mean change on the Montgomery-Asberg Depression Rating Scale. Secondary outcomes include functioning, substance use, mania ratings, and quality of life. Blood samples will be collected at baseline and week 16 to explore biochemical alterations following treatment. CONCLUSION: This study may provide a novel adjunctive treatment for bipolar depression. Analysis of biological samples may assist in understanding the therapeutic benefits and the underlying etiology of bipolar depression. TRIAL REGISTRATION: Australian and New Zealand Clinical Trial Registry ACTRN12612000830897.
Assuntos
Acetilcisteína/uso terapêutico , Transtorno Bipolar/terapia , Transtorno Depressivo/terapia , Suplementos Nutricionais , Sequestradores de Radicais Livres/uso terapêutico , Doenças Mitocondriais/terapia , Adulto , Antidepressivos/uso terapêutico , Antioxidantes/uso terapêutico , Terapia Combinada/métodos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Placebos/uso terapêutico , Escalas de Graduação Psiquiátrica , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do Tratamento , Ubiquinona/análogos & derivados , Ubiquinona/uso terapêutico , Vitamina K 3/uso terapêutico , Vitaminas/uso terapêuticoRESUMO
PURPOSE: Because of a dismal prognosis for advanced renal-cell carcinoma (RCC), an alternative therapeutic approach, using vitamin K3 (VK3) and D-fraction (DF) was investigated. VK3 is a synthetic VK derivative and DF is a bioactive mushroom extract, and they have been shown to have antitumor activity. We examined if the combination of VK3 and DF would exhibit the improved anticancer effect on RCC in vitro. MATERIALS AND METHODS: Human RCC, ACHN cell line, were treated with varying concentrations of VK3, DF, or a combination of the two. Cell viability was assessed at 72 hours by MTT assay. To explore the possible anticancer mechanism, studies on cell cycle, chromatin modifications, and apoptosis were conducted. RESULTS: VK3 alone led to a ~20% reduction in cell viability at 4 µM, while DF alone induced a 20% to 45% viability reduction at ≥ 500 µg/mL. A combination of VK3 (4 µM) and DF (300 µg/mL) led to a drastic >90% viability reduction, however. Cell cycle analysis indicated that VK3/DF treatment induced a G1 cell cycle arrest, accompanied by the up-regulation of p21(WAF1) and p27(Kip1). Histone deacetylase (HDAC) was also significantly (~60%) inactivated, indicating chromatin modifications. In addition, Western blot analysis revealed that the up-regulation of Bax and activation of poly-(ADP-ribose)-polymerase (PARP) were seen in VK3/DF-treated cells, indicating induction of apoptosis. CONCLUSIONS: The combination of VK3 and DF can lead to a profound reduction in ACHN cell viability, through a p21(WAF1)-mediated G1 cell cycle arrest, and ultimately induces apoptosis. Therefore, the combination of VK3/DF may have clinical implications as an alternative, improved therapeutic modality for advanced RCC.
Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/patologia , Grifola/química , Neoplasias Renais/patologia , Vitamina K 3/uso terapêutico , Western Blotting , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Citometria de Fluxo , Humanos , Neoplasias Renais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Vitaminas/uso terapêuticoRESUMO
Many cancers are deficient in catalase activity, and maintain a moderate level of oxidative stress to aid their proliferation and survival. It may prove feasible to achieve substantial selective tumor kill with a three-pronged strategy for acutely exacerbating oxidative stress in cancer cells: inducing increased production of oxidants in tumors with sustained high-dose infusions of sodium ascorbate and menadione, while concurrently undercutting the antioxidant defenses of cancer cells by imposing glucose deprivation - as with 2-deoxyglucose administration or a hypoglycemic insulin clamp - and by suppressing hypoxia-inducible factor-1 activity with available agents such as salicylate, rapamycin, and irinotecan. Inhibition of pyruvate dehydrogenase-1 with dichloroacetate may also promote oxidative stress in hypoxic cancer cells. Cell culture studies could be employed to devise effective protocols that could be tested in xenografted rodents and, ultimately, in exploratory clinical trials.
Assuntos
Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/uso terapêutico , Catalase/metabolismo , Glucose/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Modelos Biológicos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piruvato Desidrogenase Quinase de Transferência de Acetil , Vitamina K 3/uso terapêuticoRESUMO
Vitamin K is a family of fat-soluble compounds including phylloquinone (vitamin K1), menaquinone (vitamin K2) and menadione (vitamin K3). Recently, it was reported that vitamin K, especially vitamins K1 and K2, exerts a variety of biological effects, and these compounds are expected to be candidates for therapeutic agents against various diseases. In this study, we investigated the anti-inflammatory effects of vitamin K3 in in vitro cultured cell experiments and in vivo animal experiments. In human embryonic kidney (HEK)293 cells, vitamin K3 inhibited the tumour necrosis factor (TNF)-alpha-evoked translocation of nuclear factor (NF)-kappaB into the nucleus, although vitamins K1 and K2 did not. Vitamin K3 also suppressed the lipopolysaccharide (LPS)-induced nuclear translocation of NF-kappaB and production of TNF-alpha in mouse macrophage RAW264.7 cells. Moreover, the addition of vitamin K3 before and after LPS administration attenuated the severity of lung injury in an animal model of acute lung injury/acute respiratory distress syndrome (ARDS), which occurs in the setting of acute severe illness complicated by systemic inflammation. In the ARDS model, vitamin K3 also suppressed the LPS-induced increase in the serum TNF-alpha level and inhibited the LPS-evoked nuclear translocation of NF-kappaB in lung tissue. Despite marked efforts, little therapeutic progress has been made, and the mortality rate of ARDS remains high. Vitamin K3 may be an effective therapeutic strategy against acute lung injury including ARDS.
Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios não Esteroides/uso terapêutico , Lipopolissacarídeos/toxicidade , NF-kappa B/antagonistas & inibidores , Vitamina K 3/uso terapêutico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Líquido da Lavagem Broncoalveolar/citologia , Células Cultivadas/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Rim , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neutrófilos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/metabolismo , Vitamina K 1/farmacologia , Vitamina K 1/uso terapêutico , Vitamina K 2/farmacologia , Vitamina K 2/uso terapêutico , Vitamina K 3/farmacologiaRESUMO
BACKGROUND AND OBJECTIVE: Cystic fibrosis (CF) patients suffer from malabsorption of fat-soluble vitamins (A, D, E and K). These vitamins are available as water-dispersible (A, D(3) and E) or water-soluble grades (K(3)), which is favoured in CF patients as they fail to absorb oil-based products. The objective of this study was to determine stability of these raw materials after opening the original package and to develop a compounded formulation of acceptable quality, stability and taste, allowing flexible dose adaptation and being appropriate for administration to children and elderly people. METHODS: The raw materials were stored after opening their original package for 8 months at 8 degrees C and room temperature (RT). Stability was assessed using a validated HPLC method after extraction of the vitamin from the cold water-soluble matrix (vitamin A acetate, D(3) and E) or using a spectrophotometrical method (vitamin K(3)). These materials were mixed with an appropriate lactose grade (lactose 80 m for vitamins A and D(3); lactose 90 m for vitamin E, lactose very fine powder for vitamin K(3)) and filled in hard gelatin capsules. Mass and content uniformity were determined and stability of the vitamins in the capsules was assessed after 2 months storage at 8 degrees C and RT. RESULTS: All raw materials showed good stability during storage in the opened original package for 8 months storage at 8 degrees C as well as RT (>95% of the initial content). The compounded formulations complied with the requirements of the European Pharmacopoeia for mass and content uniformity and can be stored for 2 months at 8 degrees C or RT while maintaining the vitamin content between 90% and 110%. CONCLUSIONS: As these fat-soluble vitamins are not commercially available on the Belgian market, compounded formulations are a valuable alternative for prophylactic administration of these vitamins to CF patients, i.e. a stable formulation, having an acceptable taste, allowing flexible dose adaptation and being appropriate for administration to children and elderly people.
Assuntos
Colecalciferol/química , Fibrose Cística/tratamento farmacológico , Vitamina A/química , Vitamina E/química , Vitamina K 3/química , Vitaminas/química , Cápsulas , Colecalciferol/administração & dosagem , Colecalciferol/uso terapêutico , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Humanos , Espectrofotometria , Paladar , Vitamina A/administração & dosagem , Vitamina A/uso terapêutico , Vitamina E/administração & dosagem , Vitamina E/uso terapêutico , Vitamina K 3/administração & dosagem , Vitamina K 3/uso terapêutico , Vitaminas/administração & dosagem , Vitaminas/uso terapêuticoRESUMO
BACKGROUND AND AIM: The survival of patients with unresectable advanced hepatocellular carcinoma (HCC) with portal vein thrombosis is dismal. Current therapeutic options have limited efficacy. Vitamin K has been shown to have antitumor effect on HCC cells both in cell lines and patients with advanced HCC. The aim of this study was to assess the clinical efficacy of high dose vitamin K3 in the treatment of advanced HCC with portal vein thrombosis. METHODS: Forty-two consecutive patients with advanced HCC (Stage C according to BCLC staging system) with portal vein thrombosis were randomized into two groups: (i) high dose vitamin K3 (n = 23); and (ii) placebo (n = 19). The vitamin K3 was administered by i.v. infusion of 50 mg/day with daily increase of dose by 50 mg for 6 days, followed by 20 mg i.m. twice daily for 2 weeks. RESULTS: Of the 23 patients treated with vitamin K, one (4.3%) achieved complete response and three (13%) partial response, for a total of four (17.4%) objective responders overall. The overall mean survival was 8.9 +/- 8.8 months (median: 6; range 1-37 months) in the vitamin K group and 6.8 +/- 5.3 months (median: 5; range 1.5-21 months) in the placebo group (P = 0.552). The mean duration of survival was longer in patients in the vitamin K group who achieved objective response (22.5 +/- 12.2; median: 21; range 11-37 months) as compared to patients not achieving objective response (6.1 +/- 4.6; median: 5; range 1-16 months) (P = 0.0.002). Portal vein thrombosis resolved with complete patency in one (4.35%) patient. CONCLUSIONS: Treatment with high dose vitamin K produces objective response in 17% patients with improved survival in patients achieving objective response; however, it does not affect the overall survival.
Assuntos
Antifibrinolíticos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Vitamina K 3/uso terapêutico , Adulto , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Placebos , Veia Porta/patologia , Taxa de Sobrevida , Resultado do Tratamento , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologiaRESUMO
Vitamin K, an essential nutrient often associated with the clotting cascade, has been the focus of considerable research demonstrating an anticancer potential. Much of this research has focused on vitamin K3, although vitamins K2 and K1 have also been shown to have anticancer effects. Early studies of vitamin K3 employed an oxidative model to explain the anticancer effects seen in both in vitro and in vivo studies; however, this model does not adequately address the action of vitamins K1 and K2. Recent research has demonstrated the anticancer action of vitamin K may act at the level of tyrosine kinases and phosphatases, modulating various transcription factors such as Myc and Fos. Tyrosine kinases associated with cyclins have also been shown to be affected by vitamin K, which can lead to cell cycle arrest and cell death.
Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias/prevenção & controle , Vitamina K/uso terapêutico , Animais , Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos , Ratos , Fatores de Transcrição/efeitos dos fármacos , Vitamina K/fisiologia , Vitamina K 1/uso terapêutico , Vitamina K 2/uso terapêutico , Vitamina K 3/uso terapêuticoRESUMO
The decision of stressed cells to die or to survive is made by integrating signals at different levels through multiple check points. However, initiation and continued progression toward cell death by apoptosis in cancer cells may be blocked by mutation of the tumor suppressor p53 or overexpression of members of the bcl-2 family of proteins. The existence of such mechanisms indicates that cancer cells lose the controls regulating their cell cycle. Therefore, the activation of their programmed cell death appears as a major therapeutic target. Oxidative stress can stimulate growth, trigger apoptosis, or cause necrosis depending upon the dose and the exposure time of the oxidizing agent. A large body of evidence supports the idea that oxidative stress induced by redox cycling of vitamins C and K(3) in association surpasses cancer cellular defense systems and results in cell death. The molecular mechanisms underlying such a process are, however, still unknown. Indeed, several types of cell death may be produced, namely autoschizis, apoptosis and necrosis. Combined vitamin C and K(3) administration in vitro and in vivo produced tumor growth inhibition and increased the life-span of tumor-bearing mice. CK(3)-treatment selectively potentiated tumor chemotherapy, produced sensitization of tumors resistant to some drugs, potentiated cancer radiotherapy and caused inhibition of the development of cancer metastases without inducing toxicity in the host. We propose the association of vitamins C and K(3) as an adjuvant cancer therapy which may be introduced into human cancer therapy without any change in the classical anticancer protocols, and without any supplementary risk for patients.