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1.
J Transl Med ; 11: 191, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23947403

RESUMEN

BACKGROUND: Ascorbic acid (vitamin C, ascorbate) is a key water soluble antioxidant that, when administered in doses well above its recommended dietary allowance, may have preventative and therapeutic value against a number of pathologies. The intravenous administration of high dose ascorbate (IVC) has increased in popularity among complementary and alternative medicine practitioners: thousands of patients received IVC, at an average dose of 0.5 g/kg, without significant side effects. While IVC may have a variety of possible applications, it has generated the most interest for its potential use in treating cancer. METHODS: Medical records of patients with cancer treated with IVC at the Riordan Clinic were retrospectively reviewed. Cancer patients, for whom plasma ascorbate concentration data before and after treatment were available, along with C-reactive protein (CRP) measurements, were chosen for analysis. RESULTS: The results of the analysis can be summarized as follows. IVC produces peak plasma ascorbate concentrations on the order of ten millimolars with lower peak plasma concentrations obtained in cancer patients as compared to healthy subjects. Cancer patients who are deficient in vitamin C prior to therapy tend to achieve lower plasma levels post infusion. High inflammation or tumor burdens, as measured by CRP or tumor antigen levels, tend to lower peak plasma ascorbate levels after IVC. When compared to patients with localized tumors, patients with metastatic tumors tend to achieve lower post infusion plasma ascorbate concentrations. CONCLUSIONS: The data indicate that, while potentially therapeutic plasma ascorbate concentrations can be achieved with IVC, levels attained will vary based on tumor burden and degree of inflammation (among other factors). Evidence suggests that IVC may be able to modulate inflammation, which in turn might improve outcomes for cancer patients. IVC may serve as a safe, adjunctive therapy in clinical cancer care.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/uso terapéutico , Inflamación/sangre , Inflamación/tratamiento farmacológico , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Administración Intravenosa , Adulto , Anciano , Anciano de 80 o más Años , Ácido Ascórbico/sangre , Biomarcadores de Tumor/metabolismo , Proteína C-Reactiva/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
2.
J Transl Med ; 10: 189, 2012 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-22963460

RESUMEN

BACKGROUND: An inflammatory component is present in the microenvironment of most neoplastic tissues. Inflammation and elevated C-reactive protein (CRP) are associated with poor prognosis and decreased survival in many types of cancer.Vitamin C has been suggested as having both a preventative and therapeutic role in a number of pathologies when administered at much higher-than-recommended dietary allowance levels.Since in vitro studies demonstrated inhibition of pro-inflammatory pathways by millimolar concentrations of vitamin C, we decided to analyze the effects of high dose IVC therapy in suppression of inflammation in cancer patients. METHODS: 45 patients with prostate cancer, breast cancer, bladder cancer, pancreatic cancer, lung cancer, thyroid cancer, skin cancer and B-cell lymphoma were treated at the Riordan Clinic by high doses of vitamin C (7.5 g -50 g) after standard treatments by conventional methods.CRP and tumor markers were measured in serum or heparin-plasma as a routine analysis. In addition, serum samples were collected before and after the IVCs for the cytokine kit tests. RESULTS: According to our data positive response to treatment, which was demonstrated by measurements of C- reactive protein, was found in 75% of patients and progression of the inflammation in 25% of patients. IVC treatments on all aggressive stage cancer patients showed the poor response of treatment.There was correlation between tumor markers (PSA, CEA, CA27.29 and CA15-3) and changes in the levels of C-reactive protein.Our test of the effect of IVC on pro-inflammatory cytokines demonstrated that inflammation cytokines IL-1α, IL-2, IL-8, TNF-α, chemokine eotaxin and CRP were reduced significantly after treatments. CONCLUSIONS: The high dose intravenous ascorbic acid therapy affects C-reactive protein levels and pro-inflammation cytokines in cancer patients. In our study, we found that modulation of inflammation by IVC correlated with decreases in tumor marker levels.In summary, our data support the hypothesis that high dose intravenous ascorbate treatments may reduce inflammation in cancer patients. Our results suggest that further investigations into the use of IVC to reduce inflammation in diseases where inflammation is relevant are warranted.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Inflamación/tratamiento farmacológico , Neoplasias/complicaciones , Relación Dosis-Respuesta a Droga , Humanos , Inflamación/complicaciones
3.
Altern Ther Health Med ; 18(1): 36-40, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22516851

RESUMEN

CONTEXT: Chronic fatigue syndrome (CFS) is a debilitating fatigue illness that has unknown etiology and lacks an objective diagnostic marker. OBJECTIVE: To examine the metabolic component of CFS to determine if practitioners can use serum NAD(P)H concentration measurements to monitor metabolism and fatigue status in patients with CFS. DESIGN: The research team conducted a case-control study, comparing a group of patients who were diagnosed with CFS with a control group of healthy subjects. The team obtained venous blood samples from fasting patients to examine the serum NAD(P)H concentrations. SETTING: The study occurred at the Riordan Clinic in Witchita, Kansas. PARTICIPANTS: The study included 44 CFS patients at the Riordan Clinic and 30 healthy control participants. The CFS patients presented a spectrum of symptoms that had existed for at least 6 months: new, unexplained, persistent, or relapsing chronic fatigue that bed rest did not resolve and that was severe enough to reduce daily activity significantly by 50% in conjunction with headache, muscle pain, pain in multiple joints, and unrefreshing sleep. In the control group, the research team enrolled subjects without diagnosis of disease or injury. OUTCOME MEASURES: The research team determined levels of serum reduced nicotinamide adenine dinucleotides (NADH and NAD[P]H) by measuring serum fluorescence emission at 450 nm. The team then conducted sensitivity and specificity analyses. Results NAD(P)H concentrations in serum of CFS participants averaged 8.0 ± 1.4 (standard deviation [SD]) nmol/mL, while those in the healthy controls averaged 10.8 ± 0.8 (SD) nmol/mL, a statistically significant difference. Using a cut-off concentration of 9.5 nmol/mL, the research team attained a sensitivity of 0.73 and a specificity of 1.0. An analysis of receiver-operator characteristics yielded an area under the curve of 0.9. The research team compared serum NAD(P)H to several endocrine and metabolic lab parameters. Serum NAD(P)H was directly correlated with serum CoQ10 levels and inversely correlated with urine hydroxyhemopyrrolin-2-one levels. CONCLUSIONS: Based on these findings, the research team proposed using serum NAD(P)H, measured as an intrinsic serum-fluorescence emission, to monitor metabolism and fatigue status in patients with CFS. Following patients NAD(P)H levels over time may aid in selecting therapeutic strategies and monitoring treatment outcomes.


Asunto(s)
Metabolismo Energético , Síndrome de Fatiga Crónica/diagnóstico , NADP/sangre , Estudios de Casos y Controles , Síndrome de Fatiga Crónica/sangre , Síndrome de Fatiga Crónica/patología , Síndrome de Fatiga Crónica/orina , Fluorescencia , Humanos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Ubiquinona/análogos & derivados , Ubiquinona/sangre
4.
Int J Med Sci ; 8(6): 445-52, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21850193

RESUMEN

Being overweight or obese is associated with an increased risk for the development of non-insulin-dependent diabetes mellitus, hypertension, and cardiovascular disease. Dyslipidemia of obesity is characterized by elevated fasting triglycerides and decreased high-density lipoprotein-cholesterol concentrations. Endothelial damage and dysfunction is considered to be a major underlying mechanism for the elevated cardiovascular risk associated with increased adiposity. Alterations in endothelial cells and stem/endothelial progenitor cell function associated with overweight and obesity predispose to atherosclerosis and thrombosis. In our study, we analyzed the effect of a low calorie diet in combination with oral supplementation by vitamins, minerals, probiotics and human chorionic gonadotropin (hCG, 125-180 IUs) on the body composition, lipid profile and CD34-positive cells in circulation. During this dieting program, the following parameters were assessed weekly for all participants: fat free mass, body fat, BMI, extracellular/intracellular water, total body water and basal metabolic rate. For part of participants blood chemistry parameters and circulating CD34-positive cells were determined before and after dieting. The data indicated that the treatments not only reduced body fat mass and total mass but also improved the lipid profile. The changes in body composition correlated with the level of lipoproteins responsible for the increased cardiovascular risk factors. These changes in body composition and lipid profile parameters coincided with the improvement of circulatory progenitor cell numbers. As the result of our study, we concluded that the improvement of body composition affects the number of stem/progenitor cells in circulation.


Asunto(s)
Antígenos CD34/metabolismo , Enfermedades Cardiovasculares/prevención & control , Pérdida de Peso/fisiología , Composición Corporal/efectos de los fármacos , Índice de Masa Corporal , Restricción Calórica , Enfermedades Cardiovasculares/metabolismo , Gonadotropina Coriónica/uso terapéutico , Femenino , Humanos , Masculino , Factores de Riesgo , Células Madre/citología , Células Madre/metabolismo , Pérdida de Peso/efectos de los fármacos
5.
J Angiogenes Res ; 2: 2, 2010 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-20150992

RESUMEN

BACKGROUND: Angiogenesis is critical to tumor growth and is therefore a potential target for cancer therapy. As many current inhibitors of angiogenesis exhibit host toxicity, natural alternatives are needed. At millimolar concentrations, ascorbate (vitamin C) inhibits migration and tubule formation by mature endothelial cells and endothelial progenitors. In the present study, we examined the effects of ascorbate, at levels relevant during intravenous infusion therapy, on angiogenesis using an ex vivo an in vivo assay. METHODS: Two assays were used to evaluate effect of high-doses ascorbic acid on angiogenesis: ex vivo rat aortic ring explant assay in Matrigel matrices and in vivo Matrigel plug assay. In aortic rings, we quantified microvessel growth, branching and vessel regression under different treatment conditions. In murine angiogenesis assay, male C57 mice 6-8 weeks old were treated by high-dose ascorbic acid and the number of microvessels was analyzed by histological method. To characterize the population of cells that formed capillary network and microvessels, the sections were stained by CD34 and CD31 antibodies. RESULTS: Results show that sprouting of endothelial tubules from aortic rings was reduced in a concentration-dependent fashion by ascorbate: while controls roughly tripled sprout densities during the study, ascorbate (1 mg/mL, 5.5 mM) actually reduced sprout density. In vivo, the ability of mice to vascularize subcutaneously implanted Matrigel plug was diminished if the mice were treated with 430 mg/kg vitamin C: numbers of vessels, and vessel densities, in plugs from treated mice were roughly 30% less than those in plugs from untreated mice. CONCLUSIONS: We conclude that the inhibition of angiogenesis by ascorbate suggested in vitro is confirmed in vivo, and that angiogenesis inhibition may be one mechanism by which intravenous ascorbate therapy shows efficacy in animal experiments and clinical case studies.

6.
P R Health Sci J ; 24(2): 145-50, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16116933

RESUMEN

Sodium ascorbate is preferentially toxic to tumor cells at high concentrations. It has not been established, however, whether sufficient intra-tumor ascorbate concentrations are safely achievable in vivo. We administered sodium ascorbate subcutaneously or orally for eighteen days to Sewall-Wright strain-2 guinea pigs bearing intradermal L-10 hepatocarcinoma tumors. Tumor masses and intra-tumor ascorbate concentrations were determined at necropsy. L-10 cells formed tumors that metastasized to the lymph nodes, with tumor burdens reaching nearly 50 grams in untreated animals. Subcutaneous injections of ascorbate (500 mg/kg/day) inhibited tumor growth by as much as sixty-five percent, with oral supplementation reducing it by roughly fifty percent. Tumor growth correlated inversely with intra-tumor ascorbate concentration, the latter exceeding 2 mM in some cases. Ascorbate concentrations sufficient to kill tumor cells can be safely achieved in solid tumors in vivo, suggesting a possible role for high dose intravenous ascorbate in treating cancer.


Asunto(s)
Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Línea Celular Tumoral/efectos de los fármacos , Animales , Antioxidantes/análisis , Ácido Ascórbico/análisis , Procesos de Crecimiento Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Cobayas , Neoplasias Hepáticas Experimentales/tratamiento farmacológico
7.
Integr Cancer Ther ; 4(1): 32-44, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15695476

RESUMEN

The effect of ascorbic acid on cancer has been a subject of great controversy. This is a follow-up review of the 1979 article by Cameron, Pauling, and Leibovitz published in Cancer Research. In this updated version, the authors address general aspects of ascorbic acid and cancer that have been presented before, while reviewing, analyzing, and updating new existing literature on the subject. In addition, they present and discuss their own mechanistic hypothesis on the effect of ascorbic acid on the cancer cell. The objective of this review is to provide an updated scientific basis for the use of ascorbic acid, especially intravenously as adjuvant treatment in pharmacological nutritional oncology.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Ácido Ascórbico/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/prevención & control , Ácido Ascórbico/administración & dosificación , Ensayos Clínicos como Asunto , Terapia Combinada , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos , Humanos , Infusiones Intravenosas , Dolor/tratamiento farmacológico , Dolor/etiología , Cuidados Paliativos
8.
P R Health Sci J ; 22(3): 287-90, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14619456

RESUMEN

High dose intravenous(i.v.) ascorbic acid (AA) has been used as therapy for infectious disease from bacterial and viral origin and adjuvant therapy for cancer. In this publication we describe a clinical protocol that has been developed over the past twenty years utilizing high dose i.v. AA as therapy for cancer. This includes principles of treatment, rationale, baseline workup, infusion protocol, precautions and side effects.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Antiinfecciosos/administración & dosificación , Antiinfecciosos/efectos adversos , Antiinfecciosos/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ácido Ascórbico/efectos adversos , Ácido Ascórbico/farmacología , Ácido Ascórbico/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Protocolos Clínicos , Relación Dosis-Respuesta a Droga , Humanos , Infusiones Intravenosas , Neoplasias/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Virosis/tratamiento farmacológico
9.
P R Health Sci J ; 21(1): 39-41, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12013679

RESUMEN

The effect of vitamin C in cancer has been a subject of great controversy; mainly because of the inconsistent results obtained by oral intakes of ascorbate when used as an anticancer agent. We believe the intravenous application of ascorbate will provide more consistent results in cancer patients since Vitamin C blood levels attained are substantially higher in a range proven cytotoxic to malignant cells. In this article we will present and discuss our proposed mechanism on the chemotherapeutic activity exhibited by ascorbate.


Asunto(s)
Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Neoplasias/tratamiento farmacológico , Terapia Ortomolecular , Humanos , Inyecciones Intravenosas
10.
P. R. health sci. j ; 21(1): 39-41, Mar. 2002.
Artículo en Inglés | LILACS | ID: lil-334020

RESUMEN

The effect of vitamin C in cancer has been a subject of great controversy; mainly because of the inconsistent results obtained by oral intakes of ascorbate when used as an anticancer agent. We believe the intravenous application of ascorbate will provide more consistent results in cancer patients since Vitamin C blood levels attained are substantially higher in a range proven cytotoxic to malignant cells. In this article we will present and discuss our proposed mechanism on the chemotherapeutic activity exhibited by ascorbate.


Asunto(s)
Humanos , Ácido Ascórbico/administración & dosificación , Antioxidantes , Neoplasias , Terapia Ortomolecular , Inyecciones Intravenosas
11.
P R Health Sci J ; 21(4): 323-8, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12572240

RESUMEN

BACKGROUND: Plant materials represent promising sources of anti-cancer agents. We developed and tested a novel extract from the ubiquitous plant Convolvulus arvensis. MATERIALS AND METHODS: Convolvulus arvensis components were extracted in boiling water, and small molecules were removed by high-pressure filtration. The extract's biological activity was assessed by measuring its effects on S-180 fibrosarcoma growth in Kun Ming mice and on heparin-induced angiogenesis in chick embryos. We also examined the extract's effects on lymphocytes ex vivo and tumor cell growth in vitro. RESULTS: The extract (primarily proteins and polysaccharides) inhibited tumor growth in a dose-dependent fashion when administered orally. At the highest dose tested, 200 mg/kg/day, tumor growth was inhibited by roughly seventy percent. Subcutaneous or intraperitoneal administration at 50 mg/kg/day also inhibited tumor growth by over seventy percent. The extract's acute LD50 in Kun Ming mice was 500 mg/kg/day when injected, indicating that tumor growth inhibition occurred at non-toxic doses. It inhibited angiogenesis in chick embryos, improved lymphocyte survival ex vivo, and enhanced yeast phagocytosis, but did not kill tumor cells in culture. CONCLUSION: High molecular mass extract deserves further study as an anti-cancer agent.


Asunto(s)
Convolvulus , Neoplasias/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Fitoterapia , Preparaciones de Plantas/uso terapéutico , Animales , Células Cultivadas , Humanos , Linfocitos/efectos de los fármacos , Ratones , Peso Molecular , Neoplasias/patología
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