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Ovarian cancer presents a significant challenge due to its high rate of chemoresistance, which complicates the effectiveness of drug-response therapy. This study provides a comprehensive metabolomic analysis of ovarian cancer cell lines OVCAR-3 and SK-OV-3, characterizing their distinct metabolic landscapes. Metabolomics coupled with chemometric analysis enabled us to discriminate between the metabolic profiles of these two cell lines. The OVCAR-3 cells, which are sensitive to doxorubicin (DOX), exhibited a preference for biosynthetic pathways associated with cell proliferation. Conversely, DOX-resistant SK-OV-3 cells favored fatty acid oxidation for energy maintenance. Notably, a marked difference in glutathione (GSH) metabolism was observed between these cell lines. Our investigations further revealed that GSH depletion led to a profound change in drug sensitivity, inducing a shift from a cytostatic to a cytotoxic response. The results derived from this comprehensive metabolomic analysis offer potential targets for novel therapeutic strategies to overcome drug resistance. Our study suggests that targeting the GSH pathway could potentially enhance chemotherapy's efficacy in treating ovarian cancer.
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Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Resistencia a Antineoplásicos , Apoptosis , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Glutatión/metabolismoRESUMEN
Introduction: Severe acute respiratory syndrome virus 2 (SARS-CoV-2) has caused over million deaths worldwide, with more than 61,000 deaths in Chile. The Chilean government has implemented a vaccination program against SARS-CoV-2, with over 17.7 million people receiving a complete vaccination scheme. The final target is 18 million individuals. The most common vaccines used in Chile are CoronaVac (Sinovac) and BNT162b2 (Pfizer-Biotech). Given the global need for vaccine boosters to combat the impact of emerging virus variants, studying the immune response to SARS-CoV-2 is crucial. In this study, we characterize the humoral immune response in inoculated volunteers from Chile who received vaccination schemes consisting of two doses of CoronaVac [CoronaVac (2x)], two doses of CoronaVac plus one dose of BNT162b2 [CoronaVac (2x) + BNT162b2 (1x)], and three doses of BNT162b2 [BNT162b2 (3x)]. Methods: We recruited 469 participants from Clínica Dávila in Santiago and the Health Center Víctor Manuel Fernández in the city of Concepción, Chile. Additionally, we included participants who had recovered from COVID-19 but were not vaccinated (RCN). We analyzed antibodies, including anti-N, anti-S1-RBD, and neutralizing antibodies against SARS-CoV-2. Results: We found that antibodies against the SARS-CoV-2 nucleoprotein were significantly higher in the CoronaVac (2x) and RCN groups compared to the CoronaVac (2x) + BNT162b2 (1x) or BNT162b2 (3x) groups. However, the CoronaVac (2x) + BNT162b2 (1x) and BNT162b2 (3x) groups exhibited a higher concentration of S1-RBD antibodies than the CoronaVac (2x) group and RCN group. There were no significant differences in S1-RBD antibody titers between the CoronaVac (2x) + BNT162b2 (1x) and BNT162b2 (3x) groups. Finally, the group immunized with BNT162b2 (3x) had higher levels of neutralizing antibodies compared to the RCN group, as well as the CoronaVac (2x) and CoronaVac (2x) + BNT162b2 (1x) groups. Discussion: These findings suggest that vaccination induces the secretion of antibodies against SARS-CoV-2, and a booster dose of BNT162b2 is necessary to generate a protective immune response. In the current state of the pandemic, these data support the Ministry of Health of the Government of Chile's decision to promote heterologous vaccination as they indicate that a significant portion of the Chilean population has neutralizing antibodies against SARS-CoV-2.
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COVID-19 , Vacunas , Humanos , Inmunidad Humoral , SARS-CoV-2 , Vacuna BNT162 , Chile , COVID-19/prevención & control , Vacunación , Anticuerpos NeutralizantesRESUMEN
Cancer is a leading cause of death worldwide and involves an oxidative stress mechanism. The transcription factor Nrf2 has a crucial role in cytoprotective response against oxidative stress, including cancer growth and progression and therapy resistance. For this reason, inhibitors of Nrf2 are new targets to be studied. Traditional plant-based remedies rich in phytochemicals have been used against human cancers and phenolic compounds are known for their chemopreventive properties. This comprehensive review offers an updated review of the role of phenolic compounds as anticancer agents due to their action on Nrf2 inhibition. In addition, the role of naturally-occurring bioactive anticancer agents are covered in the clinical applications of polyphenols as Nrf2 inhibitors. Video Abstract.
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Antineoplásicos , Neoplasias , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Estrés Oxidativo , Antioxidantes/metabolismo , Fenoles/farmacología , Fenoles/uso terapéuticoRESUMEN
Endothelial progenitor cells (EPCs) are stem cells mainly derived from bone marrow; from where they migrate to repair and regenerate damaged tissues. eEPCs have been classified into two sub-populations, early (eEPC) and late EPCs (lEPC), depending on maturation stages in vitro. In addition, eEPC release endocrine mediators, including small extracellular vesicles (sEVs), which in turn may enhance the eEPC-mediated wound healing properties. Nevertheless, adenosine contributes to angiogenesis by recruiting eEPC at the injury site. However, whether ARs may enhance the secretome of eEPC, including sEVs, is unknown. Therefore, we aimed to investigate whether AR activation increase the release of sEVs in eEPC, which in turn has paracrine effects on recipient endothelial cells. Results shown that 5'-N-ethylcarboxamidoadenosine (NECA), a non-selective agonist, increase both the protein levels of the vascular endothelial growth factor (VEGF), and the number of sEVs released to the conditioned medium (CM) in primary culture of eEPC. Importantly, CM and EVs harvested from NECA-stimulated eEPC promote in vitro angiogenesis, without changes in cell proliferation, in recipient ECV-304 endothelial cells. This constitutes the first evidence showing that adenosine enhances sEVs release from eEPC, which has pro-angiogenic capacity on recipient endothelial cells.
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Células Progenitoras Endoteliales , Humanos , Células Progenitoras Endoteliales/metabolismo , Adenosina/farmacología , Adenosina/metabolismo , Adenosina-5'-(N-etilcarboxamida)/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Células Madre/metabolismo , Medios de Cultivo Condicionados/metabolismoRESUMEN
Objective: To determine the association between Obstructive Sleep Apnea (OSA) with long-term symptoms and inflammatory cytokines, exploring the changes between 4-months and 1-year after COVID-19 infection. Methods: We conducted an observational, prospective cohort study, including patients ≥18 years old with confirmed diagnosis of COVID-19 between April to July 2020. All participants underwent two clinical follow-up visits, the first at 4-months (Visit 1) and the second at 1 year, after SARS-CoV-2 infection (Visit 2). Plasma glucose, total cholesterol, HDL, and triglycerides. Regarding pulmonary function, spirometry and lung diffusion capacity tests were assessed. For mental and neurocognitive evaluation, a short-form (SF-12), Beck depression and Hospital-Anxiety depression questionnaires were conducted at both time-points, whereas the Montreal Cognitive assessment was conducted during the second follow-up. Regarding to sleep evaluation, Epworth Sleepiness Scale, Insomnia Severity index and STOP-BANG questionnaire were conducted. Additionally, a home sleep apnea test and 7-day wrist actigraphy were performed in all participants. Inflammatory cytokines were measured using an inflammatory cytokine bead array kit. p-values < 0.05 were considered statistically significant and statistical analyses were performed using R software. Results: A total of 60 patients were included in the first follow-up, from which 57 completed the second follow-up. The mean age was 46.4 years-old (SD ± 13.1) and 53.3% were male. 30% of cases reported mild COVID-19 infection, 28.3% with moderate illness, and 41.6% with severe illness. Moreover, 56.6% of them were admitted to the ICU. Regarding to metabolic values, the OSA group showed higher values of insulin resistance (IR) (27%), systolic blood pressure (SBP) 135.2 (±19.1), dyslipidemia (67.5%), total cholesterol 202.1 (±60.5), triglycerides 176.1 (±119.0) and HOMA-IR 9.0 (±18.8) in comparison with the non-OSA group. 1 year after COVID-19 infection, DLCO test remains abnormal in OSA patients (25% OSA vs. 3.6% non-OSA, p = 0.02). Finally, those participants with OSA who develop ARDS reported an adjusted OR 20.4 (95%-CI, 1.04-504) risk of neurocognitive impairment. Discussion: Among patients with previous COVID-19, OSA impact the development of incident glycemic, neurocognitive impairment, and abnormal functional pulmonary changes that persist up to 1 year since acute phase.
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Oxidized low-density lipoprotein (ox-LDL) is the most harmful form of cholesterol associated with vascular atherosclerosis and hepatic injury, mainly due to inflammatory cell infiltration and subsequent severe tissue injury. Lox-1 is the central ox-LDL receptor expressed in endothelial and immune cells, its activation regulating inflammatory cytokines and chemotactic factor secretion. Recently, a Lox-1 truncated protein isoform lacking the ox-LDL binding domain named LOXIN has been described. We have previously shown that LOXIN overexpression blocked Lox-1-mediated ox-LDL internalization in human endothelial progenitor cells in vitro. However, the functional role of LOXIN in targeting inflammation or tissue injury in vivo remains unknown. In this study, we investigate whether LOXIN modulated the expression of Lox-1 and reduced the inflammatory response in a high-fat-diet mice model. Results indicate that human LOXIN blocks Lox-1 mediated uptake of ox-LDL in H4-II-E-C3 cells. Furthermore, in vivo experiments showed that overexpression of LOXIN reduced both fatty streak lesions in the aorta and inflammation and fibrosis in the liver. These findings were associated with the down-regulation of Lox-1 in endothelial cells. Then, LOXIN prevents hepatic and aortic tissue damage in vivo associated with reduced Lox-1 expression in endothelial cells. We encourage future research to understand better the underlying molecular mechanisms and potential therapeutic use of LOXIN.
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Aterosclerosis , Células Progenitoras Endoteliales , Ftalazinas , Animales , Aorta/metabolismo , Aorta/patología , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/etiología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Células Cultivadas , Dieta Alta en Grasa/efectos adversos , Células Progenitoras Endoteliales/efectos de los fármacos , Células Progenitoras Endoteliales/metabolismo , Células Progenitoras Endoteliales/patología , Inflamación/tratamiento farmacológico , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Lipoproteínas LDL/metabolismo , Hígado/metabolismo , Ratones , Ftalazinas/farmacología , Receptores Depuradores de Clase E/genética , Receptores Depuradores de Clase E/metabolismoRESUMEN
Tissue regeneration is often impaired in patients with metabolic disorders such as diabetes mellitus and obesity, exhibiting reduced wound repair and limited regeneration capacity. We and others have demonstrated that wound healing under normal metabolic conditions is potentiated by the secretome of human endothelial cell-differentiated mesenchymal stem cells (hMSC-EC). However, it is unknown whether this effect is sustained under hyperglycemic conditions. In this study, the wound healing effect of secretomes from undifferentiated human mesenchymal stem cells (hMSC) and hMSC-EC in a type-2 diabetes mouse model was analyzed. hMSC were isolated from human Wharton's jelly and differentiated into hMSC-EC. hMSC and hMSC-EC secretomes were analyzed and their wound healing capacity in C57Bl/6J mice fed with control (CD) or high fat diet (HFD) was evaluated. Our results showed that hMSC-EC secretome enhanced endothelial cell proliferation and wound healing in vivo when compared with hMSC secretome. Five soluble proteins (angiopoietin-1, angiopoietin-2, Factor de crecimiento fibroblástico, Matrix metallopeptidase 9, and Vascular Endothelial Growth Factor) were enriched in hMSC-EC secretome in comparison to hMSC secretome. Thus, the five recombinant proteins were mixed, and their pro-healing property was evaluated in vitro and in vivo. Functional analysis demonstrated that a cocktail of these proteins enhanced the wound healing process similar to hMSC-EC secretome in HFD mice. Overall, our results show that hMSC-EC secretome or a combination of specific proteins enriched in the hMSC-EC secretome enhanced wound healing process under hyperglycemic conditions.
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Medios de Cultivo Condicionados/farmacología , Diabetes Mellitus Tipo 2/metabolismo , Células Madre Mesenquimatosas/citología , Proteínas Recombinantes/farmacología , Cicatrización de Heridas/efectos de los fármacos , Angiopoyetina 1/metabolismo , Angiopoyetina 1/farmacología , Angiopoyetina 2/metabolismo , Angiopoyetina 2/farmacología , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Medios de Cultivo Condicionados/química , Diabetes Mellitus Tipo 2/inducido químicamente , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Humanos , Metaloproteinasa 9 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/farmacología , Células Madre Mesenquimatosas/metabolismo , Ratones , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/farmacología , Gelatina de Wharton/citología , Gelatina de Wharton/metabolismoRESUMEN
INTRODUCTION: Patients with severe COVID-19 develops an acute respiratory distress syndrome (ARDS), requiring admission to the intensive care unit. COVID-19 also reports an increased prevalence of comorbidities, similar to patients with Sleep disorder breathing (SDB). OBJECTIVES: To evaluate the association between undiagnosed SDB and the risk of ARDS and pulmonary abnormalities in a cohort of patients' survivors of COVID-19 between 3 and 6 months after diagnosis. METHODS: Prospective cohort study of patients who developed ARDS during hospitalization due to COVID-19 compared with a control group of patients who had COVID-19 with mild to moderate symptoms. All patients were evaluated between the 12th and 24th week after SARS-CoV-2 infection. The evaluation includes persistent symptoms, lung diffusing capacity of carbon monoxide (DLCO), chest CT scan and home sleep apnea test. SDB was diagnosed by the respiratory disturbance index ≥5 ev/h. The association between SDB and ARDS, the hazards of lung impairment and the hazard ratios (HR) were analyzed. RESULTS: A total of 60 patients were included (ARDS: 34 patients, Control: 26 patients). The mean follow-up was 16 weeks (range 12-24). ARDS reported a high prevalence of SDB (79% vs. 38% in control group). A total of 35% reported DLCO impairment, and 67.6% abnormal chest CT. SDB was independently associated to ARDS, OR 6.72 (CI, 1.56-28.93), p < 0.01, and abnormal Chest CT, HR 17.2 (CI, 1.68-177.4, p = 0.01). Besides, ARDS, days in mechanical ventilation, male gender were also associated with an increased risk of abnormal chest CT. CONCLUSION: Undiagnosed SDB is prevalent and independently associated with ARDS. In addition, undiagnosed SDB increased the hazard of abnormal Chest CT in the midterm. STUDY REGISTER: ISRCTN16865246.
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COVID-19 , Síndrome de Dificultad Respiratoria , Síndromes de la Apnea del Sueño , COVID-19/complicaciones , COVID-19/epidemiología , Estudios de Seguimiento , Humanos , Pulmón/diagnóstico por imagen , Masculino , Estudios Prospectivos , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/epidemiología , Síndrome de Dificultad Respiratoria/etiología , Factores de Riesgo , SARS-CoV-2 , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/epidemiologíaRESUMEN
BACKGROUND: Coronavirus disease 2019 (COVID-19) ranges from asymptomatic disease to respiratory failure and requires invasive mechanical ventilation (IMV). Data about the sequelae after infection are scarce. The study aims to describe the prevalence of symptoms, pulmonary function tests (PFTs), and radiological changes after four months of follow-up. METHODS: A prospective, cross-sectional, multicentre study was performed. Patients with different illness severities were consecutively included (mild; moderate: hospitalized without IMV; severe: hospitalized with IMV). Clinical variables, health-related quality of life (HRQoL), PFT (spirometry, diffusing capacity of the lungs for carbon monoxide (DLCO)), and (CT) scans of the chest were obtained. The association between the risk of sequelae (DLCO <80%) and altered CT was analysed using logistic regression adjusted for confounding variables. RESULTS: 60 patients (18 mild, 17 moderate, and 25 severe) were included. Fatigue was found in 11% of the mild, 47% of the moderate and 36% of the severe group. Altered DLCO (mild: 5.5%, moderate: 41%, severe: 28%, p < .05) and change in HRQoL (mild: 50%, moderate: 94%, severe: 60%), while the severe group showed a higher prevalence of altered CT (88% vs. 64%). Awake prone position (APP) and high-flow nasal cannula (HFNC) was independently associated with altered DLCO, Odds ratio (OR) 7.28 (CI, 1.10-47.81; p < .05), and altered CT, OR 9.50 (CI, 1.26-71.5; p < .05). Besides, prolonged time in IMV was associated with altered CT, OR 1.24 (CI, 1.05-1.46; p < .05). DISCUSSION: It is common to find sequelae in symptoms, radiology, and PFT. In our series, the use of APP+HFNC and days on IMV were associated with an increased risk of sequelae.
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COVID-19 , Radiología , Estudios Transversales , Humanos , Pulmón/diagnóstico por imagen , Estudios Prospectivos , Calidad de Vida , SARS-CoV-2RESUMEN
Myrtenal is a natural monoterpene isolated from essential oils of several plants and their derivates have shown to have several biological properties including cytotoxicity. The cytotoxic activity of these derivates are being investigated for their antitumor effect leading to the development of potential anticancer agents. In this study, novels Myrtenyl grafted pseudo-peptides were designed, synthesized and functionally characterized as possible therapeutic agents for cancer treatment. Thirteen novel Myrtenyl grafted pseudo-peptides were prepared in high atom economy and efficiency by a classic Ugi-4CR and sequential post-modification. Their structures were confirmed by NMR, and ESI-MS, and its cytotoxic activity was evaluated in three cancer cell lines and primary CD4+ T cells at different proliferative cycles. Our results revealed that some of these compounds showed significant cytotoxicity against human gastric, breast and colon adenocarcinoma cells lines, but not against human dermal fibroblast cell line. Moreover, from the thirteen novel myrtenyl synthesized the compound (1R,5S)-N-{[1-(3-chlorophenyl)-1H-1,2,3-triazol-4-yl]methyl}-N-[2-(cyclohexylamino)-2-oxoethyl]-6,6-dimethylbicyclo[3.1.1]hept-2-ene-2-carboxamide (3b) proved to be the best candidate in terms of acceptable EC50, and Emax values in cancer cell lines and at inducing cytotoxicity in CD4+ T cells undergoing active proliferation, without affecting non-proliferating T cells. Overall, the synthesis and characterization of our Myrtenyl derivates revealed novel potential anticancer candidates with selective cytotoxic activity.
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Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Técnicas de Química Sintética , Péptidos/síntesis química , Péptidos/farmacología , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Péptidos/química , Relación Estructura-ActividadRESUMEN
For many years, cardiovascular disease (CVD) has been the leading cause of death around the world. Often associated with CVD are comorbidities such as obesity, abnormal lipid profiles and insulin resistance. Insulin is a key hormone that functions as a regulator of cellular metabolism in many tissues in the human body. Insulin resistance is defined as a decrease in tissue response to insulin stimulation thus insulin resistance is characterized by defects in uptake and oxidation of glucose, a decrease in glycogen synthesis, and, to a lesser extent, the ability to suppress lipid oxidation. Literature widely suggests that free fatty acids are the predominant substrate used in the adult myocardium for ATP production, however, the cardiac metabolic network is highly flexible and can use other substrates, such as glucose, lactate or amino acids. During insulin resistance, several metabolic alterations induce the development of cardiovascular disease. For instance, insulin resistance can induce an imbalance in glucose metabolism that generates chronic hyperglycemia, which in turn triggers oxidative stress and causes an inflammatory response that leads to cell damage. Insulin resistance can also alter systemic lipid metabolism which then leads to the development of dyslipidemia and the well-known lipid triad: (1) high levels of plasma triglycerides, (2) low levels of high-density lipoprotein, and (3) the appearance of small dense low-density lipoproteins. This triad, along with endothelial dysfunction, which can also be induced by aberrant insulin signaling, contribute to atherosclerotic plaque formation. Regarding the systemic consequences associated with insulin resistance and the metabolic cardiac alterations, it can be concluded that insulin resistance in the myocardium generates damage by at least three different mechanisms: (1) signal transduction alteration, (2) impaired regulation of substrate metabolism, and (3) altered delivery of substrates to the myocardium. The aim of this review is to discuss the mechanisms associated with insulin resistance and the development of CVD. New therapies focused on decreasing insulin resistance may contribute to a decrease in both CVD and atherosclerotic plaque generation.
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Glucemia/metabolismo , Enfermedades Cardiovasculares/sangre , Endotelio Vascular/metabolismo , Trastornos del Metabolismo de la Glucosa/sangre , Resistencia a la Insulina , Insulina/sangre , Animales , Biomarcadores/sangre , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Comorbilidad , Dislipidemias/sangre , Dislipidemias/epidemiología , Dislipidemias/fisiopatología , Endotelio Vascular/fisiopatología , Trastornos del Metabolismo de la Glucosa/epidemiología , Trastornos del Metabolismo de la Glucosa/fisiopatología , Humanos , Inflamación/sangre , Inflamación/epidemiología , Inflamación/fisiopatología , Mediadores de Inflamación/sangre , Lípidos/sangre , Pronóstico , Factores de Riesgo , Transducción de SeñalRESUMEN
Background: It is known that some nutrients play an important role in the development of cholelithiasis. Cholesterol is carried by micelles and vesicles in the bile. During the first stage of gallstone formation, cholesterol crystals derive from thermodynamically unstable vesicles. Aim: To determine the effect of a high fat diet on blood lipids and bile composition, and its implication in the formation of gallstones. Material and Methods: Two groups of 15 BALB/c mice each, coming from the same litter, were treated with a control or with a high-fat diet (64% fat and 0.14% cholesterol). After two months, the animals were sacrificed, blood and bile samples were obtained. Serum glucose and the corresponding lipid profiles were measured. In bile samples, cholesterol and phospholipid levels were analyzed, and cholesterol transporters (vesicles and micelles) were separated by gel filtration chromatography. Results: Treated animals showed an 87% increase in serum total cholesterol (p < 0.01), a 97% increase in HDL-cholesterol (p < 0.05) and a 140% increase in LDL-cholesterol (p < 0.05). No changes in serum triglycerides or glucose were observed. In bile, a 13% increase in biliary cholesterol (p < 0.05) was observed but no change in biliary phospholipids. Also, an increase in biliary vesicular transporters and an increase of cholesterol/phospholipid ratio in vesicular transporters were observed. Conclusions: A high fat diet may contribute to the formation of gallstones in our experimental model.
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Animales , Masculino , Grasas de la Dieta/metabolismo , Cálculos Biliares/etiología , Cálculos Biliares/metabolismo , Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Fosfolípidos/metabolismo , Bilis/química , Transporte Biológico , Grasas de la Dieta/análisis , Colesterol/análisis , Estudios Prospectivos , Resultado del Tratamiento , Modelos Animales , Vesícula Biliar/metabolismo , Ratones Endogámicos BALB CRESUMEN
BACKGROUND: It is known that some nutrients play an important role in the development of cholelithiasis. Cholesterol is carried by micelles and vesicles in the bile. During the first stage of gallstone formation, cholesterol crystals derive from thermodynamically unstable vesicles. AIM: To determine the effect of a high fat diet on blood lipids and bile composition, and its implication in the formation of gallstones. MATERIAL AND METHODS: Two groups of 15 BALB/c mice each, coming from the same litter, were treated with a control or with a high-fat diet (64% fat and 0.14% cholesterol). After two months, the animals were sacrificed, blood and bile samples were obtained. Serum glucose and the corresponding lipid profiles were measured. In bile samples, cholesterol and phospholipid levels were analyzed, and cholesterol transporters (vesicles and micelles) were separated by gel filtration chromatography. RESULTS: Treated animals showed an 87% increase in serum total cholesterol (p < 0.01), a 97% increase in HDL-cholesterol (p < 0.05) and a 140% increase in LDL-cholesterol (p < 0.05). No changes in serum triglycerides or glucose were observed. In bile, a 13% increase in biliary cholesterol (p < 0.05) was observed but no change in biliary phospholipids. Also, an increase in biliary vesicular transporters and an increase of cholesterol/phospholipid ratio in vesicular transporters were observed. CONCLUSIONS: A high fat diet may contribute to the formation of gallstones in our experimental model.
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Colesterol/metabolismo , Dieta Alta en Grasa/efectos adversos , Grasas de la Dieta/metabolismo , Cálculos Biliares/etiología , Cálculos Biliares/metabolismo , Animales , Bilis/química , Transporte Biológico , Colesterol/análisis , Grasas de la Dieta/análisis , Vesícula Biliar/metabolismo , Masculino , Ratones Endogámicos BALB C , Modelos Animales , Fosfolípidos/metabolismo , Estudios Prospectivos , Resultado del TratamientoRESUMEN
Mesenchymal stem cells (MSCs) are adult multipotent stem cells that are able to differentiate into multiple specialized cell types including osteocytes, adipocytes, and chondrocytes. MSCs exert different functions in the body and have recently been predicted to have a major clinical/therapeutic potential. However, the mechanisms of self-renewal and tissue regeneration are not completely understood. It has been shown that the biological effect depends mainly on its paracrine action. Furthermore, it has been reported that the secretion of soluble factors and the release of extracellular vesicles, such as exosomes, could mediate the cellular communication to induce cell-differentiation/self-renewal. This review provides an overview of MSC-derived exosomes in promoting angiogenicity and of the clinical relevance in a therapeutic approach.
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The bioavailability of nitric oxide (NO) represents a key marker in vascular health. A decrease in NO induces a pathological condition denominated endothelial dysfunction, syndrome observed in different pathologies, such as obesity, diabetes, kidney disease, cardiovascular disease, and preeclampsia (PE). PE is one of the major risks for maternal death and fetal loss. Recent studies suggest that the placenta of pregnant women with PE express high levels of lectin-like oxidized LDL receptor-1 (LOX-1), which induces endothelial dysfunction by increasing reactive oxygen species (ROS) and decreasing intracellular NO. Besides LOX-1 activation induces changes in migration and apoptosis of syncytiotrophoblast cells. However, the role of this receptor in placental tissue is still unknown. In this review we will describes the physiological roles of LOX-1 in normal placenta development and the potential involvement of this receptor in the pathophysiology of PE.
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Feto/irrigación sanguínea , Feto/fisiopatología , Lectinas/metabolismo , Lipoproteínas LDL/metabolismo , Placenta/irrigación sanguínea , Placenta/fisiopatología , Preeclampsia/fisiopatología , Femenino , Humanos , Óxido Nítrico/metabolismo , EmbarazoRESUMEN
Although there is in vivo evidence suggesting a role for glutathione in the metabolism and tissue distribution of vitamin C, no connection with the vitamin C transport systems has been reported. We show here that disruption of glutathione metabolism with buthionine-(S,R)-sulfoximine (BSO) produced a sustained blockade of ascorbic acid transport in rat hepatocytes and rat hepatoma cells. Rat hepatocytes expressed the Na(+)-coupled ascorbic acid transporter-1 (SVCT1), while hepatoma cells expressed the transporters SVCT1 and SVCT2. BSO-treated rat hepatoma cells showed a two order of magnitude decrease in SVCT1 and SVCT2 mRNA levels, undetectable SVCT1 and SVCT2 protein expression, and lacked the capacity to transport ascorbic acid, effects that were fully reversible on glutathione repletion. Interestingly, although SVCT1 mRNA levels remained unchanged in rat hepatocytes made glutathione deficient by in vivo BSO treatment, SVCT1 protein was absent from the plasma membrane and the cells lacked the capacity to transport ascorbic acid. The specificity of the BSO treatment was indicated by the finding that transport of oxidized vitamin C (dehydroascorbic acid) and glucose transporter expression were unaffected by BSO treatment. Moreover, glutathione depletion failed to affect ascorbic acid transport, and SVCT1 and SVCT2 expression in human hepatoma cells. Therefore, our data indicate an essential role for glutathione in controlling vitamin C metabolism in rat hepatocytes and rat hepatoma cells, two cell types capable of synthesizing ascorbic acid, by regulating the expression and subcellular localization of the transporters involved in the acquisition of ascorbic acid from extracellular sources, an effect not observed in human cells incapable of synthesizing ascorbic acid.
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Carcinoma Hepatocelular/metabolismo , Glutatión/metabolismo , Hepatocitos/metabolismo , Neoplasias Hepáticas/metabolismo , Transportadores de Sodio Acoplados a la Vitamina C/metabolismo , Animales , Ácido Ascórbico/administración & dosificación , Secuencia de Bases , Butionina Sulfoximina/farmacología , Carcinoma Hepatocelular/patología , Cartilla de ADN , Glutatión/antagonistas & inhibidores , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/patología , Ratas , Ratas Sprague-DawleyRESUMEN
We studied the acquisition of dehydroascorbic acid by rat hepatocytes, H4IIE rat hepatoma cells and Xenopus laevis oocytes. Transport kinetics and competition and inhibition studies revealed that rat hepatocytes transport oxidized dehydroascorbic acid through a single functional component possessing the functional and kinetic properties expected for the glucose transporter GLUT2. On the other hand, rat hepatoma cells showed expression of at least two dehydroascorbic acid transporters with the expected functional and kinetic properties expected for GLUT1 and GLUT2. Expression studies of GLUT2 in X. laevis oocytes followed by transport kinetics and competition and inhibition studies revealed that GLUT2 is a low affinity dehydroascorbic transporter whose kinetic and functional properties match those observed for the endogenous GLUT2 transporter in rat hepatocytes and rat hepatoma cells. Therefore, GLUT2, a transporter known as a low affinity transporter of glucose and fructose and a high affinity transporter of glucosamine is also a low affinity dehydroascorbic acid transporter.
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Ácido Deshidroascórbico/metabolismo , Transportador de Glucosa de Tipo 2/metabolismo , Hepatocitos/metabolismo , Animales , Línea Celular Tumoral , Transportador de Glucosa de Tipo 2/genética , Oocitos , Ratas , Xenopus laevisRESUMEN
Subunit vaccines are a suitable alternative for the control of classical swine fever. However, such vaccines have as the main drawback the relatively long period of time required to induce a protective response, which hampers their use under outbreak conditions. In this work, type I interferon is used as an immunostimulating molecule in order to increase the immunogenicity of a vaccine candidate based on the E2-CSFV antigen produced in goat milk. Pigs vaccinated with E2-CSFV antigen co-formulated with recombinant human alpha interferon were protected against clinical signs and viremia as early as 7 days post-vaccination. It was also demonstrated that interferon stimulates a response of specific anti-CSFV neutralizing antibodies. The present work constitutes the first report of a subunit vaccine able to confer complete protection by the end of the first week after vaccination. These results suggest that the E2-CSFV antigen combined with type I interferons could be potentially used under outbreak conditions to stop CSFV spread and for eradication programs in CSF enzootic areas.
Asunto(s)
Antígenos Virales/inmunología , Peste Porcina Clásica/prevención & control , Interferón-alfa/inmunología , Proteínas del Envoltorio Viral/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Línea Celular , Virus de la Fiebre Porcina Clásica/inmunología , Cabras , Humanos , Masculino , Leche/inmunología , Leche/virología , Proteínas Recombinantes/inmunología , Porcinos/inmunología , Vacunas de Subunidad/inmunologíaRESUMEN
Na(+)-coupled ascorbic acid transporter-2 (SVCT2) activity is impaired at acid pH, but little is known about the molecular determinants that define the transporter pH sensitivity. SVCT2 contains six histidine residues in its primary sequence, three of which are exofacial in the transporter secondary structure model. We used site-directed mutagenesis and treatment with diethylpyrocarbonate to identify histidine residues responsible for SVCT2 pH sensitivity. We conclude that five histidine residues, His(109), His(203), His(206), His(269), and His(413), are central regulators of SVCT2 function, participating to different degrees in modulating pH sensitivity, transporter kinetics, Na(+) cooperativity, conformational stability, and subcellular localization. Our results are compatible with a model in which (i) a single exofacial histidine residue, His(413), localized in the exofacial loop IV that connects transmembrane helices VII-VIII defines the pH sensitivity of SVCT2 through a mechanism involving a marked attenuation of the activation by Na(+) and loss of Na(+) cooperativity, which leads to a decreased V(max) without altering the transport K(m); (ii) exofacial histidine residues His(203), His(206), and His(413) may be involved in maintaining a functional interaction between exofacial loops II and IV and influence the general folding of the transporter; (iii) histidines 203, 206, 269, and 413 affect the transporter kinetics by modulating the apparent transport K(m); and (iv) histidine 109, localized at the center of transmembrane helix I, might be fundamental for the interaction of SVCT2 with the transported substrate ascorbic acid. Thus, histidine residues are central regulators of SVCT2 function.
Asunto(s)
Histidina/metabolismo , Riñón/metabolismo , Melanoma/metabolismo , Proteínas de la Membrana/metabolismo , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Sodio/metabolismo , Simportadores/metabolismo , Ácido Ascórbico/metabolismo , Transporte Biológico , Biotinilación , Membrana Celular/metabolismo , Histidina/química , Histidina/genética , Humanos , Concentración de Iones de Hidrógeno , Riñón/citología , Cinética , Mutagénesis Sitio-Dirigida , Transportadores de Anión Orgánico Sodio-Dependiente/genética , Conformación Proteica , Transportadores de Sodio Acoplados a la Vitamina C , Fracciones Subcelulares , Simportadores/genéticaRESUMEN
We characterized the human Na(+)-ascorbic acid transporter SVCT2 and developed a basic model for the transport cycle that challenges the current view that it functions as a Na(+)-dependent transporter. The properties of SVCT2 are modulated by Ca(2+)/Mg(2+) and a reciprocal functional interaction between Na(+) and ascorbic acid that defines the substrate binding order and the transport stoichiometry. Na(+) increased the ascorbic acid transport rate in a cooperative manner, decreasing the transport K(m) without affecting the V(max), thus converting a low affinity form of the transporter into a high affinity transporter. Inversely, ascorbic acid affected in a bimodal and concentration-dependent manner the Na(+) cooperativity, with absence of cooperativity at low and high ascorbic acid concentrations. Our data are consistent with a transport cycle characterized by a Na(+):ascorbic acid stoichiometry of 2:1 and a substrate binding order of the type Na(+):ascorbic acid:Na(+). However, SVCT2 is not electrogenic. SVCT2 showed an absolute requirement for Ca(2+)/Mg(2+) for function, with both cations switching the transporter from an inactive into an active conformation by increasing the transport V(max) without affecting the transport K(m) or the Na(+) cooperativity. Our data indicate that SVCT2 may switch between a number of states with characteristic properties, including an inactive conformation in the absence of Ca(2+)/Mg(2+). At least three active states can be envisioned, including a low affinity conformation at Na(+) concentrations below 20 mM and two high affinity conformations at elevated Na(+) concentrations whose Na(+) cooperativity is modulated by ascorbic acid. Thus, SVCT2 is a Ca(2+)/Mg(2+)-dependent transporter.