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We propose a simple mechanism for the self-replication of protocells. Our main hypothesis is that the amphiphilic molecules composing the membrane bilayer are synthesized inside the protocell through exothermic chemical reactions. The slow increase of the inner temperature forces the hottest molecules to move from the inner leaflet to the outer leaflet of the bilayer. Because of this outward translocation flow, the outer leaflet grows faster than the inner leaflet. This differential growth increases the mean curvature and amplifies any local shrinking of the protocell until it splits in two. The proposed model, based on mere laws of physics, is a step in the study of the origin of life, as well as a clue for a better understanding of cell proliferation in cancer.
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Células Artificiales , MembranasRESUMEN
Hyperosmotic conditions are associated to several pathological states. In this article, we evaluate the consequence of hyperosmotic medium on cellular energy metabolism. We demonstrate that exposure of cells to hyperosmotic conditions immediately reduces the mitochondrial oxidative phosphorylation rate. This causes an increase in glycolysis, which represses further respiration. This is known as the Warburg or Crabtree effect. In addition to aerobic glycolysis, we observed two other cellular responses that would help to preserve cellular ATP level and viability: A reduction in the cellular ATP turnover rate and a partial mitochondrial uncoupling which is expected to enhance ATP production by Krebs cycle. The latter is likely to constitute another metabolic adaptation to compensate for deficient oxidative phosphorylation that, importantly, is not dependent on glucose.
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Neuroblastoma/metabolismo , Consumo de Oxígeno/fisiología , Animales , Células CHO , Línea Celular Tumoral , Supervivencia Celular , Cricetinae , Cricetulus , Metabolismo Energético , Células HEK293 , Humanos , Masculino , Mitocondrias/metabolismo , Ratas , Ratas WistarRESUMEN
COVID-19, a pandemic disease caused by a viral infection, is associated with a high mortality rate. Most of the signs and symptoms, e.g. cytokine storm, electrolytes imbalances, thromboembolism, etc., are related to mitochondrial dysfunction. Therefore, targeting mitochondrion will represent a more rational treatment of COVID-19. The current work outlines how COVID-19's signs and symptoms are related to the mitochondrion. Proper understanding of the underlying causes might enhance the opportunity to treat COVID-19.
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Tratamiento Farmacológico de COVID-19 , COVID-19/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Antivirales/química , Antivirales/farmacología , COVID-19/metabolismo , Humanos , Mitocondrias/metabolismo , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/patogenicidadRESUMEN
A hyper-specialization characterizes modern medicine with the consequence of classifying the various diseases of the body into unrelated categories. Such a broad diversification of medicine goes in the opposite direction of physics, which eagerly looks for unification. We argue that unification should also apply to medicine. In accordance with the second principle of thermodynamics, the cell must release its entropy either in the form of heat (catabolism) or biomass (anabolism). There is a decreased flow of entropy outside the body due to an age-related reduction in mitochondrial entropy yield resulting in increased release of entropy in the form of biomass. This shift toward anabolism has been known in oncology as Warburg-effect. The shift toward anabolism has been reported in most diseases. This quest for a single framework is reinforced by the fact that inflammation (also called the immune response) is involved in nearly every disease. This strongly suggests that despite their apparent disparity, there is an underlying unity in the diseases. This also offers guidelines for the repurposing of old drugs.
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Inmunidad/fisiología , Medicina/clasificación , Metabolismo/fisiología , Especialización/normas , Reposicionamiento de Medicamentos , Entropía , Guías como Asunto , HumanosRESUMEN
Alzheimer's disease (AD) and cancer have much in common than previously recognized. These pathologies share common risk factors (inflammation and aging), with similar epidemiological and biochemical features such as impaired mitochondria. Metabolic reprogramming occurs during aging and inflammation. We assume that inflammation is directly responsible of the Warburg effect in cancer cells, with a decreased oxidative phosphorylation and a compensatory highthroughput glycolysis (HTG). Similarly, the Warburg effect in cancer is thought to support an alkaline intracellular pH (pHi), a key component of unrelenting cell growth. In the brain, inflammation results in increased secretion of lactate by astrocytes. The increased uptake of lactic acid by neurons results in the inverse Warburg effect, such as seen in AD. The neuronal activity is dampened by a fall of pHi. Pronounced cytosol acidification results in decreased mitochondrial energy yield as well as apoptotic cell death. The link between AD and cancer is reinforced by the fact that treatment aiming at restoring the mitochondrial activity have been experimentally shown to be effective in both diseases. Low carb diet, lipoic acid, and/or methylene blue could then appear promising in both sets of these clinically diverse diseases.
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Enfermedad de Alzheimer , Enfermedades Metabólicas , Neoplasias , Glucólisis , Humanos , Concentración de Iones de Hidrógeno , Fosforilación OxidativaRESUMEN
As stated by Otto Warburg nearly a century ago, cancer is a metabolic disease, a fermentation caused by malfunctioning mitochondria, resulting in increased anabolism and decreased catabolism. Treatment should, therefore, aim at restoring the energy yield. To decrease anabolism, glucose uptake should be reduced (ketogenic diet). To increase catabolism, the oxidative phosphorylation should be restored. Treatment with a combination of α-lipoic acid and hydroxycitrate has been shown to be effective in multiple animal models. This treatment, in combination with conventional chemotherapy, has yielded extremely encouraging results in glioblastoma, brain metastasis and lung cancer. Randomized trials are necessary to confirm these preliminary data. The major limitation is the fact that the combination of α-lipoic acid and hydroxycitrate can only be effective if the mitochondria are still present and/or functional. That may not be the case in the most aggressive tumors. The increased intracellular alkalosis is a strong mitogenic signal, which bypasses most inhibitory signals. Concomitant correction of this alkalosis may be a very effective treatment in case of mitochondrial failure.
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Neoplasias/terapia , Oxígeno/metabolismo , Animales , Citratos/administración & dosificación , Humanos , Concentración de Iones de Hidrógeno , Neoplasias/metabolismo , Fosforilación Oxidativa , Ácido Tióctico/administración & dosificaciónRESUMEN
Currently, the predominant hypothesis explains cellular differentiation and behaviour as an essentially genetically driven intracellular process, suggesting a gene-centrism paradigm. However, although many living species genetic has now been described, there is still a large gap between the genetic information interpretation and cell behaviour prediction. Indeed, the physical mechanisms underlying the cell differentiation and proliferation, which are now known or suspected to guide such as the flow of energy through cells and tissues, have been often overlooked. We thus here propose a complementary conceptual framework towards the development of an energy-oriented classification of cell properties, that is, a mitochondria-centrism hypothesis based on physical forces-driven principles. A literature review on the physical-biological interactions in a number of various biological processes is analysed from the point of view of the fluid and solid mechanics, electricity and thermodynamics. There is consistent evidence that physical forces control cell proliferation and differentiation. We propose that physical forces interfere with the cell metabolism mostly at the level of the mitochondria, which in turn control gene expression. The present perspective points towards a paradigm shift complement in biology.
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Fenómenos Biofísicos , Diferenciación Celular , Animales , Proliferación Celular , Campos Electromagnéticos , Humanos , Mitocondrias/metabolismo , ÓsmosisRESUMEN
INTRODUCTION: Exposure to traumatic brain injury is a core risk factor that predisposes an individual to sporadic neurodegenerative diseases. We provide evidence that mechanical stress increases brain levels of hallmark proteins associated with neurodegeneration. METHODS: Wild-type mice were exposed to multiple regimens of repetitive mild traumatic brain injury, generating a range of combinations of impact energies, frequencies, and durations of exposure. Brain concentrations of amyloid ß 1-42 (Aß1-42), total tau, and α-synuclein were measured by sandwich enzyme-linked immunosorbent assay. RESULTS: There was a highly significant main effect of impact energy, frequency, and duration of exposure on Aß1-42, tau, and α-synuclein levels (P < .001), and a significant interaction between impact energy and duration of exposure for Aß1-42 and tau (P < .001), but not for α-synuclein. DISCUSSION: Dose-dependent and cumulative influence of repetitive mild traumatic brain injury-induced mechanical stress may trigger and/or accelerate neurodegeneration by pushing protein concentration over the disease threshold.
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Péptidos beta-Amiloides/metabolismo , Conmoción Encefálica/metabolismo , Encéfalo/metabolismo , Fragmentos de Péptidos/metabolismo , alfa-Sinucleína/metabolismo , Proteínas tau/metabolismo , Animales , Fenómenos Biomecánicos , Modelos Animales de Enfermedad , Masculino , Ratones Endogámicos BALB C , Distribución Aleatoria , Estrés MecánicoRESUMEN
INTRODUCTION: Extracellular accumulation of amyloid-ß protein and intracellular accumulation of tau in brain tissues have been described in animal models of Alzheimer's disease (AD) and mechanical stress-based diseases of different mechanisms, such as traumatic brain injury (TBI), arterial hypertension (HTN), and normal pressure hydrocephalus (NPH). METHODS: We provide a brief overview of experimental models of TBI, HTN, and NPH showing features of tau-amyloid pathology, neuroinflammation, and neuronal loss. RESULTS: "Alzheimer-like" hallmarks found in these mechanical stress-based models were compared with AD features found in transgenic models. DISCUSSION: The goal of this review is, therefore, to build on current concepts of onset and progression of AD lesions. We point to the importance of accumulated mechanical stress in brain as an environmental and endogenous factor that pushes protein deposition and neuronal injury over the disease threshold. We further encourage the development of preventing strategies and drug screening based on mechanical stress models.
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Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/fisiopatología , Encéfalo/patología , Estrés Mecánico , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Animales , Animales Modificados Genéticamente , Modelos Animales de Enfermedad , Humanos , Proteínas tau/genética , Proteínas tau/metabolismoRESUMEN
INTRODUCTION: The effects related to endogenous mechanical energy in Alzheimer's disease (AD) pathology have been widely overlooked. With the support of available data from literature and mathematical arguments, we hypothesize that brain atrophy in AD could be co-driven by the cumulative impact of the pressure within brain tissues. METHODS: Brain volumetric and physical data in AD and normal aging (NA) were extracted from the literature. Average brain shrinkage and axial deformations were evaluated mathematically. Mechanical stress equivalents related to brain shrinkage were calculated using a conservation law derived from fluid and solid mechanics. RESULTS: Pressure equivalents of 5.92 and 3.43 mm Hg were estimated in AD and in NA, respectively. DISCUSSION: The calculated increments of brain mechanical stress in AD, which could be impacted by marked dampening of arterial pulse waves, may point to the need to expand the focus on the mechanical processes underpinning pathologic aging of the brain.
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Enfermedad de Alzheimer/patología , Encéfalo/patología , Estrés Mecánico , Adulto , Anciano , Envejecimiento/patología , Algoritmos , Atrofia/patología , Encéfalo/fisiopatología , Humanos , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Tamaño de los Órganos , Presión , Adulto JovenRESUMEN
Cancer cells cooperate with stromal cells and use their environment to promote tumor growth. Energy production depends on nutrient availability and O2 concentration. Well-oxygenated cells are highly proliferative and reorient the glucose metabolism towards biosynthesis, whereas glutamine oxidation replenishes the TCA cycle coupled with OXPHOS-ATP production. Glucose, glutamine and alanine transformations sustain nucleotide and fatty acid synthesis. In contrast, hypoxic cells slow down their proliferation, enhance glycolysis to produce ATP and reject lactate which is recycled as fuel by normoxic cells. Thus, glucose is spared for biosynthesis and/or for hypoxic cell function. Environmental cells, such as fibroblasts and adipocytes, serve as food donors for cancer cells, which reject waste products (CO2 , Hâº, ammoniac, polyamines ) promoting EMT, invasion, angiogenesis and proliferation. This metabolic-coupling can be considered as a form of commensalism whereby non-malignant cells support the growth of cancer cells. Understanding these cellular cooperations within tumors may be a source of inspiration to develop new anti-cancer agents.
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Neoplasias/metabolismo , Neoplasias/patología , Células del Estroma/metabolismo , Microambiente Tumoral/fisiología , Adipocitos/fisiología , Animales , Proliferación Celular , Humanos , Inmunidad Celular , Neoplasias/inmunología , Oxígeno/metabolismoAsunto(s)
Acetilcoenzima A/metabolismo , Antineoplásicos/farmacología , Coenzima A Transferasas/antagonistas & inhibidores , Dieta Cetogénica , Neoplasias/terapia , Antineoplásicos/uso terapéutico , Coenzima A Transferasas/metabolismo , Terapia Combinada/métodos , Humanos , Hígado/citología , Hígado/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias/metabolismo , Efecto Warburg en Oncología/efectos de los fármacosRESUMEN
The different phases of the eukaryotic cell cycle are exceptionally well-preserved phenomena. DNA decompaction, RNA and protein synthesis (in late G1 phase) followed by DNA replication (in S phase) and lipid synthesis (in G2 phase) occur after resting cells (in G0) are committed to proliferate. The G1 phase of the cell cycle is characterized by an increase in the glycolytic metabolism, sustained by high NAD+/NADH ratio. A transient cytosolic acidification occurs, probably due to lactic acid synthesis or ATP hydrolysis, followed by cytosolic alkalinization. A hyperpolarized transmembrane potential is also observed, as result of sodium/potassium pump (NaK-ATPase) activity. During progression of the cell cycle, the Pentose Phosphate Pathway (PPP) is activated by increased NADP+/NADPH ratio, converting glucose 6-phosphate to nucleotide precursors. Then, nucleic acid synthesis and DNA replication occur in S phase. Along with S phase, unpublished results show a cytosolic acidification, probably the result of glutaminolysis occurring during this phase. In G2 phase there is a decrease in NADPH concentration (used for membrane lipid synthesis) and a cytoplasmic alkalinization occurs. Mitochondria hyperfusion matches the cytosolic acidification at late G1/S transition and then triggers ATP synthesis by oxidative phosphorylation. We hypothesize here that the cytosolic pH may coordinate mitochondrial activity and thus the different redox cycles, which in turn control the cell metabolism.
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Ciclo Celular , Adenosina Difosfato/metabolismo , Adenosina Trifosfato/metabolismo , Carbono/metabolismo , Concentración de Iones de Hidrógeno , Espacio Intracelular/metabolismo , Mitocondrias/metabolismo , Oxidación-ReducciónRESUMEN
Ovarian cancer remains a significant challenge, especially in platinum-resistant cases where treatment options are limited. In this study, we investigated the potential of methylene blue (MB) as a metabolic therapy and complementary treatment approach for ovarian cancer. Our findings demonstrated a significant in vivo reduction in the proliferation of TOV112D-based ovarian-cell-line xenografts. In this preclinical study, which used a carboplatin-resistant ovarian cancer tumor model implanted into mice, MB-mediated metabolic therapy exhibited superior tumor slowdown compared to carboplatin treatment alone. This indicates, for the first time, MB's potential as an alternative or adjuvant treatment, especially for resistant cases. Our in vitro study on TOV112D and ARPE-19 sheds light on the impact of such an MB-based metabolic therapy on mitochondrial energetics (respiration and membrane potential). MB showed a modulatory role in the oxygen consumption rate and the mitochondrial membrane potential. These results revealed, for the first time, that MB specifically targets TOV112D mitochondria and probably induces cell apoptosis. The differential response of normal (ARPE-19) and cancer (TOV112D) cells to the MB treatment suggests potential alterations in cancer cell mitochondria, opening avenues for therapeutic approaches that target the mitochondria. Overall, our findings suggest the efficacy of MB as a possible treatment for ovarian cancer and provide valuable insights into the mechanisms underlying the efficacy of methylene blue metabolic therapy in ovarian cancer treatment.
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Cellular metabolic alterations are now well described as implicated in cancer and some strategies are currently developed to target these different pathways. In previous papers, we demonstrated that a combination of molecules (namely alpha-lipoic acid and hydroxycitrate, i.e. Metabloc™) targeting the cancer metabolism markedly decreased tumor cell growth in mice. In this work, we demonstrate that the addition of capsaicin further delays tumor growth in mice in a dose dependant manner. This is true for the three animal model tested: lung (LLC) cancer, bladder cancer (MBT-2) and melanoma B16F10. There was no apparent side effect of this ternary combination. The addition of a fourth drug (octreotide) is even more effective resulting in tumor regression in mice bearing LLC cancer. These four compounds are all known to target the cellular metabolism not its DNA. The efficacy, the apparent lack of toxicity, the long clinical track records of these medications in human medicine, all points toward the need for a clinical trial. The dramatic efficacy of treatment suggests that cancer may simply be a disease of dysregulated cellular metabolism.
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Capsaicina/uso terapéutico , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Citratos/uso terapéutico , Melanoma Experimental/tratamiento farmacológico , Ácido Tióctico/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Animales , Antioxidantes/uso terapéutico , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patología , Humanos , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Fármacos del Sistema Sensorial/uso terapéutico , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
We previously demonstrated that most diseases display a form of anabolism due to mitochondrial impairment: in cancer, a daughter cell is formed; in Alzheimer's disease, amyloid plaques; in inflammation cytokines and lymphokines. The infection by Covid-19 follows a similar pattern. Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction. This unrelenting anabolism leads to the cytokine storm, chronic fatigue, chronic inflammation or neurodegenerative diseases. Drugs such as Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism. Similarly, coMeBining Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism.
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COVID-19 , Ácido Tióctico , Humanos , Ácido Tióctico/metabolismo , Azul de Metileno , Glicoproteína de la Espiga del Coronavirus/metabolismo , Oxidación-Reducción , InflamaciónRESUMEN
Recent epidemiological studies have suggested a link between cancer and pathophysiological conditions associated with hyperinsulinemia. In this report, we address the possible role of insulin exposure in melanocyte transformation. To this aim, normal melanocytes were exposed to chronic insulin and glucose supplementation (twice the standard medium concentration) for at least 3 wk. After 3-wk treatment, melanocytes increased proliferation (doubling time: 2.7 vs. 5.6 days, P < 0.01). After 3-wk treatment or after 3-wk treatment followed by 4-wk reculture in standard medium, melanocytes were able to grow in soft agar colonies. Treated melanocytes had increased DNA content (+8%, P < 0.05), chromosomal aberrations, and modified oncoprotein profile: p-Akt expression increased (+32%, P < 0.01), Akt decreased, and c-Myc increased (+40%, P < 0.05). PP2A protein expression increased (+42, P < 0.05), while PP2A methylation decreased (-42%, P < 0.05), and PP2A activity was reduced (-27%, P < 0.05). PP2A transcription level was increased (ppp2r1a, PP2A subunit A, +44%, P < 0.05). Also, transcriptomic data revealed modifications in insr (insulin receptors, +10%, P < 0.05) and Il8 (inflammation protein, +99%, P < 0.01). Glycolysis was modified with increased transcription of Pgk1 and Hif1a (P < 0.05), decreased transcription of Pfkfb3 (P < 0.05), decreased activity of pyruvate kinase (P < 0.01), and decreased pyruvate cell content as assessed by (1)H-NMR spectroscopy. In addition, methyl group metabolism was altered with decreased global DNA methylation (-51%, P < 0.01), increased cytosolic protein methylation (+18%, P < 0.05), and consistent changes in methylated species on (1)H-NMR spectra. In conclusion, exposure to chronic insulin and glucose supplementation induces oncogenic changes and methyl group metabolism redistribution, which may be a biomarker of transformation.
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Transformación Celular Neoplásica/efectos de los fármacos , Glucosa/farmacología , Hipoglucemiantes/farmacología , Insulina/farmacología , Melanocitos/efectos de los fármacos , Proteína Fosfatasa 2/metabolismo , Western Blotting , Ciclo Celular/efectos de los fármacos , Fraccionamiento Celular , Niño , Preescolar , Medios de Cultivo , ADN/metabolismo , Relación Dosis-Respuesta a Droga , Glucólisis/efectos de los fármacos , Humanos , Marcaje Isotópico , Cariotipificación , Espectroscopía de Resonancia Magnética , Masculino , Metilación , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/patología , Piruvato Quinasa/metabolismo , Transducción de Señal/efectos de los fármacos , Células MadreRESUMEN
Alterations in metabolic pathways are known to characterize cancer. In order to suppress cancer growth, however, multiple proteins involved in these pathways have to be targeted simultaneously. We have developed a screening method to assess the best drug combination for cancer treatment based on targeting several factors implicated in tumor specific metabolism. Following a review of the literature, we identified those enzymes known to be deregulated in cancer and established a list of sixty-two drugs targeting them. These molecules are used routinely in clinical settings for diseases other than cancer. We screened a first library in vitro against four cell lines and then evaluated the most promising binary combinations in vivo against three murine syngeneic cancer models, (LL/2, Lewis lung carcinoma; B16-F10, melanoma; and MBT-2, bladder cancer). The optimum result was obtained using a combination of α-lipoic acid and hydroxycitrate (METABLOC(TM)). In this study, a third agent was added by in vivo evaluation of a large number of combinations. The addition of octreotide strongly reduced tumor development (T/C% value of 30.2 to 34.5%; P < 0.001) in the same models and prolonged animal survival (P < 0.001) as compared to cisplatin. These results were confirmed in a different laboratory setting using a human xenograft model (NCI-H69, small cell lung cancer). None of these three molecules are known to target DNA. The effectiveness of this combination in several animal models, as well as the low toxicity of these inexpensive drugs, emphasizes the necessity of rapidly setting up a clinical trial.
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Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Animales , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Citratos/farmacología , Citratos/uso terapéutico , Modelos Animales de Enfermedad , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Ratones Endogámicos C57BL , Neoplasias/patología , Octreótido/farmacología , Octreótido/uso terapéutico , Reproducibilidad de los Resultados , Ácido Tióctico/farmacología , Ácido Tióctico/uso terapéutico , Resultado del TratamientoRESUMEN
Altered metabolism of cancer first highlighted by Otto Warburg has a long history. Although ignored for a considerable amount of time, it is now receiving substantial attention. We recently published results obtained with a combination of two drugs, lipoic acid and hydroxycitrate, targeting metabolic enzymes particularly affected in cancer: ATP citrate lyase and pyruvate dehydrogenase kinase. This treatment was as efficient as chemotherapy in the three mouse cancer models that were tested. In this work, we asked if our drug combination could be used in conjunction with standard cytotoxic chemotherapy, in particular cisplatin, to improve basic protocol efficacy. A combination of lipoic acid and hydroxycitrate was administered to mice implanted with syngeneic cancer cells, LL/2 lung carcinoma and MBT-2 bladder carcinoma, concommitantly with classical chemotherapy (cisplatin or methotrexate). We demonstrate that the triple combination lipoic acid + hydroxycitrate + cisplatin or methotrexate is more efficient than cisplatin or methotrexate used individually or the combination of lipoic acid and hydroxycitrate administered alone. Of particular note are the results obtained in the treatment of an 80 year-old female who presented with ductal adenocarcinoma of the pancreas accompanied by liver metastases. A treatment course using gemcitabine plus α-lipoic acid and hydroxycitrate gave highly promising results. The in vivo data, coupled with the case study results, suggest a possible advantage in using a treatment targeted at cancer metabolism in association with classical chemotherapy.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Metabolismo Energético/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Anciano de 80 o más Años , Animales , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patología , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundario , Línea Celular Tumoral , Cisplatino/administración & dosificación , Citratos/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Humanos , Metotrexato/administración & dosificación , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Ácido Tióctico/administración & dosificación , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología , GemcitabinaRESUMEN
1- Oncogenes express proteins of "Tyrosine kinase receptor pathways", a receptor family including insulin or IGF-Growth Hormone receptors. Other oncogenes alter the PP2A phosphatase brake over these kinases. 2- Experiments on pancreatectomized animals; treated with pure insulin or total pancreatic extracts, showed that choline in the extract, preserved them from hepatomas. Since choline is a methyle donor, and since methylation regulates PP2A, the choline protection may result from PP2A methylation, which then attenuates kinases. 3- Moreover, kinases activated by the boosted signaling pathway inactivate pyruvate kinase and pyruvate dehydrogenase. In addition, demethylated PP2A would no longer dephosphorylate these enzymes. A "bottleneck" between glycolysis and the oxidative-citrate cycle interrupts the glycolytic pyruvate supply now provided via proteolysis and alanine transamination. This pyruvate forms lactate (Warburg effect) and NAD+ for glycolysis. Lipolysis and fatty acids provide acetyl CoA; the citrate condensation increases, unusual oxaloacetate sources are available. ATP citrate lyase follows, supporting aberrant transaminations with glutaminolysis and tumor lipogenesis. Truncated urea cycles, increased polyamine synthesis, consume the methyl donor SAM favoring carcinogenesis. 4- The decrease of butyrate, a histone deacetylase inhibitor, elicits epigenic changes (PETEN, P53, IGFBP decrease; hexokinase, fetal-genes-M2, increase). 5- IGFBP stops binding the IGF - IGFR complex, it is perhaps no longer inherited by a single mitotic daughter cell; leading to two daughter cells with a mitotic capability. 6- An excess of IGF induces a decrease of the major histocompatibility complex MHC1, Natural killer lymphocytes should eliminate such cells that start the tumor, unless the fever prostaglandin PGE2 or inflammation, inhibit them...