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The incidence of kidney disease is increasing worldwide. Acute kidney injury (AKI) can strongly favor cardio-renal syndrome (CRS) type 3 development. However, the mechanism involved in CRS development is not entirely understood. In this sense, mitochondrial impairment in both organs has become a central axis in CRS physiopathology. This study aimed to elucidate the molecular mechanisms associated with cardiac mitochondrial impairment and its role in CRS development in the folic acid-induced AKI (FA-AKI) model. Our results showed that 48 h after FA-AKI, the administration of N-acetyl-cysteine (NAC), a mitochondrial glutathione regulator, prevented the early increase in inflammatory and cell death markers and oxidative stress in the heart. This was associated with the ability of NAC to protect heart mitochondrial bioenergetics, principally oxidative phosphorylation (OXPHOS) and membrane potential, through complex I activity and the preservation of glutathione balance, thus preventing mitochondrial dynamics shifting to fission and the decreases in mitochondrial biogenesis and mass. Our data show, for the first time, that mitochondrial bioenergetics impairment plays a critical role in the mechanism that leads to heart damage. Furthermore, NAC heart mitochondrial preservation during an AKI event can be a valuable strategy to prevent CRS type 3 development.
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There is increasing evidence that either ingested or produced fructose may have a role in metabolic syndrome. While not commonly considered a criterion for metabolic syndrome, cardiac hypertrophy is often associated with metabolic syndrome, and its presence carries increased cardiovascular risk. Recently it has been shown that fructose and fructokinase C (KHK) can be induced in cardiac tissue. Here we tested whether diet-induced metabolic syndrome causes heart disease associated with increased fructose content and metabolism and whether it can be prevented with a fructokinase inhibitor (osthole). Male Wistar rats were provided a control diet (C) or high fat/sugar diet for 30 days (MS), with half of the latter group receiving osthol (MS+OT, 40 mg/kg/d). The Western diet increased fructose, uric acid, and triglyceride concentrations in cardiac tissue associated with cardiac hypertrophy, local hypoxia, oxidative stress, and increased activity and expression of KHK in cardiac tissue. Osthole reversed these effects. We conclude that the cardiac changes in metabolic syndrome involve increased fructose content and its metabolism and that blocking fructokinase can provide cardiac benefit through the inhibition of KHK with modulation of hypoxia, oxidative stress, hypertrophy, and fibrosis.
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Resumen Las enfermedades cardiovasculares (ECV) comprenden un grupo de enfermedades cuyo denominador común es la afectación de vasos sanguíneos, corazón y ritmo cardiaco. El tratamiento de las ECV representa costos muy altos para los sistemas de salud y está enfocado en el control de los factores de riesgo. A pesar de existir una gran variedad de fármacos para el tratamiento de las ECV, estas continúan siendo las principales causas de mortalidad, posiblemente debido a que su origen es multifactorial y por ello se requiere de más de un fármaco. En este contexto, la alicina, un compuesto derivado del ajo, ha mostrado regular la expresión de vías de señalización y factores de riesgo asociados a la progresión de las ECV. Por ello el objetivo del presente trabajo es revisar los mecanismos celulares y moleculares por medio de los cuales la alicina ejerce sus efectos terapéuticos y describir las evidencias científicas del porqué la alicina podría representar un potencial candidato para coadyuvar en el tratamiento de las ECV.
Abstract Cardiovascular diseases (CVD) include a group of diseases whose common denominator is the affection of the blood vessels, heart, and heart rate. The treatment of CVD represents high costs to the health systems and is focused on the control of risk factors. Despite the existence of a great variety of treatments of the CVD, these continue as the main cause of mortality mainly due to the multifactorial origin, and therefore more than one drug is required. In this context, allicin, a compound derived from garlic, has shown regulate the expression of signaling pathways and risk factors associated with the progression of CVD. Therefore, the objective of this work is to review the cellular and molecular mechanisms through which allicin exert its therapeutic effects and to describe the scientific evidences why allicin represents a potential candidate to assist in the treatment of CVD.
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Cardiovascular diseases (CVDs) are a group of diseases in which the common denominator is the affection of blood vessels, heart tissue, and heart rhythm. The genesis of CVD is complex and multifactorial; therefore, approaches are often based on multidisciplinary management and more than one drug is used to achieve the optimal control of risk factors (dyslipidemia, hypertension, hypertrophy, oxidative stress, endothelial dysfunction, inflammation). In this context, allicin, a sulfur compound naturally derived from garlic, has shown beneficial effects on several cardiovascular risk factors through the modulation of cellular mechanisms and signaling pathways. Effective pharmacological treatments for CVD or its risk factors have not been developed or are unknown in clinical practice. Thus, this work aimed to review the cellular mechanisms through which allicin exerts its therapeutic effects and to show why it could be a therapeutic option for the prevention or treatment of CVD and its risk factors.
Assuntos
Doenças Cardiovasculares , Alho , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/prevenção & controle , Dissulfetos/uso terapêutico , Humanos , Ácidos Sulfínicos/farmacologia , Ácidos Sulfínicos/uso terapêuticoRESUMO
Las enfermedades cardiovasculares (ECV) comprenden un grupo de enfermedades cuyo denominador común es la afectación de vasos sanguíneos, corazón y ritmo cardiaco. El tratamiento de las ECV representa costos muy altos para los sistemas de salud y está enfocado en el control de los factores de riesgo. A pesar de existir una gran variedad de fármacos para el tratamiento de las ECV, estas continúan siendo las principales causas de mortalidad, posiblemente debido a que su origen es multifactorial y por ello se requiere de más de un fármaco. En este contexto, la alicina, un compuesto derivado del ajo, ha mostrado regular la expresión de vías de señalización y factores de riesgo asociados a la progresión de las ECV. Por ello el objetivo del presente trabajo es revisar los mecanismos celulares y moleculares por medio de los cuales la alicina ejerce sus efectos terapéuticos y describir las evidencias científicas del porqué la alicina podría representar un potencial candidato para coadyuvar en el tratamiento de las ECV.Cardiovascular diseases (CVD) include a group of diseases whose common denominator is the affection of the blood vessels, heart, and heart rate. The treatment of CVD represents high costs to the health systems and is focused on the control of risk factors. Despite the existence of a great variety of treatments of the CVD, these continue as the main cause of mortality mainly due to the multifactorial origin, and therefore more than one drug is required. In this context, allicin, a compound derived from garlic, has shown regulate the expression of signaling pathways and risk factors associated with the progression of CVD. Therefore, the objective of this work is to review the cellular and molecular mechanisms through which allicin exert its therapeutic effects and to describe the scientific evidences why allicin represents a potential candidate to assist in the treatment of CVD.
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Doenças Cardiovasculares , Doenças Cardiovasculares/epidemiologia , Humanos , Estudos Retrospectivos , Fatores de RiscoRESUMO
Fructose metabolism and hyperuricemia have been shown to drive insulin resistance, metabolic syndrome, hepatic steatosis, hypertension, inflammation, and innate immune reactivity in experimental studies. We suggest that these adverse effects are at least in part the result of suppressed activity of sirtuins, particularly Sirtuin1. Deficiency of sirtuin deacetylations is a consequence of reduced bioavailability of its cofactor nicotinamide adenine dinucleotide (NAD+). Uric acid-induced inflammation and oxidative stress consume NAD+ and activation of the polyol pathway of fructose and uric acid synthesis also reduces the NAD+-to-NADH ratio. Variability in the compensatory regeneration of NAD+ could result in variable recovery of sirtuin activity that may explain the inconsistent benefits of treatments directed to reduce uric acid in clinical trials. Here, we review the pathogenesis of the metabolic dysregulation driven by hyperuricemia and their potential relationship with sirtuin deficiency. In addition, we discuss therapeutic options directed to increase NAD+ and sirtuins activity that may improve the adverse effects resulting from fructose and uric acid synthesis.
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Resistência à Insulina , Sirtuínas , Frutose/efeitos adversos , Frutose/metabolismo , Humanos , NAD/metabolismo , Sirtuínas/metabolismo , Ácido ÚricoRESUMO
The five-sixth nephrectomy (5/6Nx) model is widely used to study the mechanisms involved in chronic kidney disease (CKD) progression. Mitochondrial impairment is a critical mechanism that favors CKD progression. However, until now, there are no temporal studies of the change in mitochondrial biogenesis and dynamics that allow determining the role of these processes in mitochondrial impairment and renal damage progression in the 5/6Nx model. In this work, we determined the changes in mitochondrial biogenesis and dynamics markers in remnant renal mass from days 2 to 28 after 5/6Nx. Our results show a progressive reduction in mitochondrial biogenesis triggered by reducing two principal regulators of mitochondrial protein expression, the peroxisome proliferator-activated receptor-gamma coactivator 1-alpha and the peroxisome proliferator-activated receptor alpha. Furthermore, the reduction in mitochondrial biogenesis proteins strongly correlates with the increase in renal damage markers. Additionally, we found a slow and gradual change in mitochondrial dynamics from fusion to fission, favoring mitochondrial fragmentation at later stages after 5/6Nx. Together, our results suggest that 5/6Nx induces the progressive reduction in mitochondrial mass over time via the decrease in mitochondrial biogenesis factors and a slow shift from mitochondrial fission to fusion; both mechanisms favor CKD progression in the remnant renal mass.
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Excessive intake of fructose results in metabolic syndrome (MS) and kidney damage, partly mediated by its metabolism by fructokinase-C or ketohexokinase-C (KHK-C). Osthol has antioxidant properties, is capable of regulating adipogenesis, and inhibits KHK-C activity. Here, we examined the potential protective role of osthol in the development of kidney disease induced by a Western (high-fat/high-sugar) diet. Control rats fed with a high-fat/high-sugar diet were compared with two groups that also received two different doses of osthol (30 mg/kg/d or 40 mg/kg/d body weight BW). A fourth group served as a normal control and received regular chow. At the end of the follow-up, kidney function, metabolic markers, oxidative stress, and lipogenic enzymes were evaluated. The Western diet induced MS (hypertension, hyperglycemia, hypertriglyceridemia, obesity, hyperuricemia), a fall in the glomerular filtration rate, renal tubular damage, and increased oxidative stress in the kidney cortex, with increased expression of lipogenic enzymes and increased kidney KHK expression. Osthol treatment prevented the development of MS and ameliorated kidney damage by inhibiting KHK activity, preventing oxidative stress via nuclear factor erythroid 2-related factor (Nrf2) activation, and reducing renal lipotoxicity. These data suggest that the nutraceutical osthol might be an ancillary therapy to slow the progression of MS and kidney damage induced by a Western diet.
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Cumarínicos/farmacologia , Dieta Ocidental/efeitos adversos , Frutoquinases/antagonistas & inibidores , Nefropatias/prevenção & controle , Síndrome Metabólica/prevenção & controle , Animais , Cumarínicos/uso terapêutico , Dieta da Carga de Carboidratos/efeitos adversos , Dieta Hiperlipídica/efeitos adversos , Frutoquinases/metabolismo , Frutose/metabolismo , Nefropatias/etiologia , Nefropatias/metabolismo , Masculino , Síndrome Metabólica/etiologia , Síndrome Metabólica/metabolismo , Fator 2 Relacionado a NF-E2 , Estresse Oxidativo , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Ratos , Ratos WistarRESUMO
Currently, there is the paradox of low water intake but increased intake of sugar-sweetened beverages (SB) in several populations; those habits are associated with an increased prevalence of metabolic derangements and greater chronic disease mortality. Persistent heat dehydration and increased SB intake stimulate the continued release of vasopressin and overactivation of the polyol-fructokinase pathway, synergizing each other, an effect partially mediated by oxidative stress. The objective of the present study was to evaluate whether water restriction concurrent with SB hydration can cause renal damage by stimulating similar pathways as heat dehydration. Three groups of male Wistar rats (n = 6) were fluid restricted; from 10 am to 12 pm animals could rehydrate with tap water (W), or sweetened beverages, one prepared with 11% of a fructose-glucose combination (SB), or with the noncaloric edulcorant stevia (ST). A normal control group of healthy rats was also studied. The animals were followed for 4 weeks. Markers of dehydration and renal damage were evaluated at the end of the study. Fluid restriction and water hydration mildly increased urine osmolality and induced a 15% fall in CrCl while increased the markers of tubular damage by NAG and KIM-1. Such changes were in association with a mild overexpression of V1a and V2 renal receptors, polyol fructokinase pathway overactivation, and increased renal oxidative stress with reduced expression of antioxidant enzymes. Hydration with SB significantly amplified those alterations, while in stevia hydrated rats, the changes were similar to the ones observed in water hydrated rats. These data suggest that current habits of hydration could be a risk factor in developing kidney damage.
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Nefropatias , Rim/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Bebidas Adoçadas com Açúcar/efeitos adversos , Animais , Desidratação/metabolismo , Desidratação/patologia , Frutoquinases/metabolismo , Frutose/efeitos adversos , Frutose/farmacologia , Glucose/efeitos adversos , Glucose/farmacologia , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Ratos , Ratos Wistar , Receptores de Vasopressinas/metabolismoRESUMO
We aimed to investigate the effects of chronic fluid restriction and hydration with a sweetened beverage (SB) in rats from weaning until adolescence, in a posterior acute kidney injury (AKI) event induced by ischemia-reperfusion (I/R). We followed 5 groups of weaning rats: control group (C); two groups with 22 h/day fluid restriction, a group hydrated for two hours with water (-W) and a group hydrated with SB; one group receiving SB ad libitum all day (+SB); and one group in which water consumption was increased using a gel diet. The rats that reached adolescence were submitted to I/R. Fluid restriction and/or SB hydration induced mild renal alterations that were significantly accentuated in the -SB group and resulted in worse outcomes after I/R-induced AKI that resulted in a catastrophic fall in creatinine clearance and diffuse acute tubular necrosis. In summary, low tap water intakes, as well as SB intake in infancy, prompt kidney worse outcomes in a later event of AKI during adolescence and both insults magnify kidney damage. Studies on hydration habits in children are recommended to disclose the potentially harmful effects that those behavioral patterns might carry to future renal health.
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Injúria Renal Aguda/etiologia , Ingestão de Líquidos , Frutose/farmacologia , Animais , Bebidas Adoçadas Artificialmente , Frutoquinases/metabolismo , Frutose/efeitos adversos , Rim/metabolismo , Rim/patologia , Testes de Função Renal , Peroxidação de Lipídeos , Lipocalina-2/metabolismo , Masculino , Estado de Hidratação do Organismo , Ratos Wistar , Receptor Tipo 1 de Angiotensina/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/etiologiaRESUMO
This study aimed to assess the impact of allicin on the course of diabetic nephropathy. Study groups included control, diabetes, and diabetes-treated rats. Allicin treatment (16 mg/kg day/p.o.) started after 1 month of diabetes onset and was administered for 30 days. In the diabetes group, the systolic blood pressure (SBP) increased, also, the oxidative stress and hypoxia in the kidney cortex were evidenced by alterations in the total antioxidant capacity as well as the expression of nuclear factor (erythroid-derived 2)-like 2/Kelch ECH associating protein 1 (Nrf2/Keap1), hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF), erythropoietin (Epo) and its receptor (Epo-R). Moreover, diabetes increased nephrin, and kidney injury molecule-1 (KIM-1) expression that correlated with mesangial matrix, the fibrosis index and with the expression of connective tissue growth factor (CTGF), transforming growth factor-ß1 (TGF-ß1), and α-smooth muscle actin (α-SMA). The insulin levels and glucose transporter protein type-4 (GLUT4) expression were decreased; otherwise, insulin receptor substrates 1 and 2 (IRS-1 and IRS-2) expression was increased. Allicin increased Nrf2 expression and decreased SBP, Keap1, HIF-1α, and VEGF expression. Concurrently, nephrin, KIM-1, the mesangial matrix, fibrosis index, and the fibrotic proteins were decreased. Additionally, allicin decreased hyperglycemia, improved insulin levels, and prevented changes in (GLUT4) and IRSs expression induced by diabetes. In conclusion, our results demonstrate that allicin has the potential to help in the treatment of diabetic nephropathy. The cellular mechanisms underlying its effects mainly rely on the regulation of antioxidant, antifibrotic, and antidiabetic mechanisms, which can contribute towards delay in the progression of renal disease.
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Chronic vasopressin secretion induced by recurrent mild heat stress exposure is significantly enhanced by limited rehydration with a fructose-containing beverage both in rodents and in humans. Moreover, this effect has been associated with upregulation of the polyol-fructokinase pathway and increased renal oxidative stress. Previously, we have shown that pharmacological inhibition of both V1a and V2 vasopressin receptors with conivaptan improved such renal alterations. The aim of this study was to evaluate the independent contributions of V1a and V2 receptors to the renal damage caused by mild heat stress and limited rehydration with a fructose-containing beverage. Osmotic minipumps were used to deliver either relcovaptan (0.64 mg/day) or tolvaptan (0.25 mg/day) in male Wistar rats for two weeks. Corresponding dilution vehicles were used as controls. To induce dehydration, rats were exposed to mild heat stress (37 °C for 1 h, Monday to Friday). All groups received a 10% fructose solution as a rehydration fluid for 2 h after mild heat stress. For the remainder of the day and on weekends, rats received tap water. The independent blockade of either the V1a or the V2 receptor prevented renal damage, reduced oxidative stress, and decreased plasma cortisol and systemic inflammation. However, the beneficial effects were regulated by different mechanisms. Tolvaptan inhibited polyol-fructokinase pathway overactivation, while relcovaptan prevented upregulation of the renin-angiotensin system and SGK1 expression. These data suggest that both V1a and V2 receptors participate in renal damage caused by heat stress-induced dehydration when fructose-containing beverages are used as rehydration fluids.
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Bebidas/análise , Frutose/metabolismo , Resposta ao Choque Térmico , Receptores de Vasopressinas/metabolismo , Animais , Hidratação , Resposta ao Choque Térmico/efeitos dos fármacos , Hidrocortisona/sangue , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Indóis/farmacologia , Córtex Renal/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Pirrolidinas/farmacologia , Ratos , Ratos Wistar , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Temperatura , Tolvaptan/farmacologia , Regulação para Cima/efeitos dos fármacosRESUMO
We investigated whether short term high fructose intake may induce early hepatic dysfunction in rats and to test whether allopurinol treatment may have beneficial effects. Twenty male Sprague-Dawley rats received 20% fructose in drinking water (10 treated with allopurinol and 10 received vehicle) and 10 control rats received tap water. After 14 days, the hepatic response to an acute fructose load was evaluated, and in fasted animals, respirometry studies in freshly isolated mitochondria were performed. In fasting rats, we did not find differences in systemic or hepatic uric acid and triglyceride concentrations among the groups, but mitochondrial respiratory control rate was significantly decreased by high fructose feeding and correlated with a reduced expression of Complex I, as well as decreased aconitase-2 activity. On the other hand, in fructose fed rats, an acute fructose load increased systemic and hepatic uric acid, triglycerides and oxidative stress. Fructose feeding was also associated with fructokinase and xanthine oxidase overexpression and increased liver de novo lipogenesis program (fatty acid synthase (FAS) and cell death-inducing DFFA-like effector C (CIDEC) overexpression, ATP citrate lyase (ACL) and acetyl coA carboxylase (ACC) overactivity and decreased AMP-activated protein kinase (AMPk) and endothelial nitric oxide synthase (eNOS) activation). Allopurinol treatment prevented hepatic and systemic alterations. These data suggest that early treatment with xanthine oxidase inhibitors might provide a therapeutic advantage by delaying or even halting the progression of non-alcoholic fatty liver disease (NAFLD).
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Alopurinol/farmacologia , Frutose/antagonistas & inibidores , Lipogênese/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Administração Oral , Alopurinol/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Frutose/administração & dosagem , Frutose/farmacologia , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Ratos Sprague-DawleyRESUMO
Recently repeated heat stress and dehydration have been reported to cause oxidative stress and kidney damage that is enhanced by rehydrating with fructose solutions. We hypothesized that antioxidants might provide a novel way to prevent kidney damage. To test this hypothesis, mild heat stress was induced by exposing rats to 37 °C during 1 h in a closed chamber. The supplementation with water-soluble antioxidants (Antiox), ascorbic acid 1% plus N-acetyl cysteine 600 mg/L was done either in the 10% fructose 2 h rehydration fluid immediately after heat stress (Fructose 10% + Antiox), and/or in the tap water (Water + Antiox) for the remainder of the day, or in both fluids. After 4 weeks, control rats exposed to heat with fructose rehydration developed impaired renal function, tubular injury, intrarenal oxidative stress, a reduction in Nrf2-Keap1 antioxidant pathway, stimulation of vasopressin and the intrarenal polyol-fructokinase pathway. In contrast, dosing the antioxidants in the tap water (i.e., before the heat exposure and rehydration with fructose) preserved renal function, prevented renal tubule dysfunction and avoided the increase in systemic blood pressure. These effects were likely due to the amplification of the antioxidant defenses through increased Nrf2 nuclear translocation stimulated by the antioxidants and by the prevention of polyol fructokinase pathway overactivation. More studies to understand the mechanisms implicated in this pathology are warranted as there is recent evidence that they may be operating in humans as well.
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Antioxidantes/farmacologia , Bebidas , Frutose/efeitos adversos , Resposta ao Choque Térmico , Nefropatias/metabolismo , Transporte Ativo do Núcleo Celular , Aldeído Redutase/metabolismo , Animais , Antioxidantes/administração & dosagem , Pressão Sanguínea , Núcleo Celular/metabolismo , Desidratação , Hidratação , Frutoquinases/metabolismo , Glutationa/metabolismo , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Polímeros/metabolismo , Transporte Proteico , Ratos , Ratos WistarRESUMO
Hyperuricemia is highly prevalent and especially common in subjects with metabolic, cardiovascular and renal diseases. In chronic kidney disease, hyperuricemia is extremely common, and uric acid (UA) excretion relies on gut uricolysis by gut microbiota. Current therapy for lowering serum UA includes drugs that may produce undesired secondary effects. Therefore, this pilot study was designed to evaluate the potential of two probiotic supplements to reduce systemic uric acid concentrations. Secondary objectives were to assess whether the hypouricemic effect related to a therapeutic benefit on the hyperuricemia-induced renal damage and hypertension. Analysis of fecal microbiota was also performed. Groups of 6 rats each were followed for 5 weeks and allocated in the following treatment groups: C = Control; HU-ND = Oxonic acid-induced hyperuricemia (HU) +regular diet; HU-P = HU+placebo; HU-F1 = HU+ probiotics formula 1 and HU-F2 = HU+ probiotics formula 2. We confirmed that oxonic acid-induced hyperuricemia produced hypertension and renal functional and structural changes, along with modest changes in the overall composition of fecal microbiota. Both probiotic-containing diets prevented HU, elevated UA urinary excretion and intrarenal UA accumulation induced by oxonic acid. The hypouricemic effect conferred by probiotic supplementation also prevented the renal changes and hypertension caused by hyperuricemia. However, probiotic treatment did not restore the fecal microbiota. In conclusion, we demonstrated for the first time the ability of probiotics containing uricolytic bacteria to lower serum uric acid in hyperuricemic animals with beneficial consequences on blood pressure and renal disease. As probiotics supplements are innocuous for human health, we recommend clinical studies to test if probiotic supplements could benefit hyperuricemic individuals.
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Suplementos Nutricionais , Hiperuricemia/induzido quimicamente , Hiperuricemia/prevenção & controle , Rim/efeitos dos fármacos , Rim/lesões , Ácido Oxônico/efeitos adversos , Probióticos/farmacologia , Animais , Citoproteção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hiperuricemia/metabolismo , Hiperuricemia/patologia , Rim/metabolismo , Rim/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Projetos Piloto , Ratos , Ratos Wistar , Ácido Úrico/metabolismoRESUMO
The potential cause-effect relationship between uric acid plasma concentrations and HDL functionality remains elusive. Therefore, this study aimed to explore the effect of oxonic acid (OA)-induced hyperuricemia on the HDL size distribution, lipid content of HDL subclasses, and apo AI turnover, as well as HDL functionality in New Zealand white rabbits. Experimental animals received OA 750 mg/kg/day by oral gavage during 21 days. The HDL-apo AI fractional catabolic rate (FCR) was determined by exogenous labeling with 125I, and HDL subclasses were determined by sequential ultracentrifugation and PAGE. Paraoxonase-1 activity (PON-1) and the effect of HDL on relaxation of aorta rings in vitro were determined as an indication of HDL functionality. Oxonic acid induced a sixfold increase of uricemia (0.84 ± 0.06 vs. 5.24 ± 0.12 mg/dL, P < 0.001), and significant decreases of triglycerides and phospholipids of HDL subclasses, whereas HDL size distribution and HDL-cholesterol remained unchanged. In addition, HDL-apo AI FCR was significantly higher in hyperuricemic rabbits than in the control group (0.03697 ± 0.0038 vs. 0.02605 ± 0.0017 h-1 respectively, P < 0.05). Such structural and metabolic changes were associated with lower levels of PON-1 activities and deleterious effects of HDL particles on endothelium-mediated vasodilation. In conclusion, hyperuricemia is associated with structural and metabolic modifications of HDL that result in impaired functionality of these lipoproteins. Our data strongly suggest that uric acid per se exerts deleterious effects on HDL that contribute to increase the risk of atherosclerosis.
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Apolipoproteína A-I/metabolismo , Hiperuricemia/sangue , Lipoproteínas HDL/sangue , Ácido Oxônico/efeitos adversos , Animais , Arildialquilfosfatase/metabolismo , Modelos Animais de Doenças , Humanos , Hiperuricemia/induzido quimicamente , Lipoproteínas HDL/química , CoelhosRESUMO
Cisplatin is widely used as chemotherapeutic agent for treatment of diverse types of cancer, however, acute kidney injury (AKI) is an important side effect of this treatment. Diverse mechanisms have been involved in cisplatin-induced AKI, such as oxidative stress, apoptosis and mitochondrial damage. On the other hand, curcumin is a polyphenol extracted from the rhizome of Curcuma longa L. Previous studies have shown that curcumin protects against the cisplatin-induced AKI; however, it is unknown whether curcumin can reduce alterations in mitochondrial bioenergetics and dynamic in this model. It was found that curcumin prevents cisplatin-induced: (a) AKI and (b) alterations in the following mitochondrial parameters: bioenergetics, ultrastructure, hydrogen peroxide production and dynamic. In fact, curcumin prevented the increase of mitochondrial fission 1 protein (FIS1), the decrease of optic atrophy 1 protein (OPA1) and the decrease of NAD+-dependent deacetylase sirtuin-3 (SIRT3), a mitochondrial dynamic regulator as well as the increase in the mitophagy associated proteins parkin and phosphatase and tensin homologue (PTEN)-induced putative kinase protein 1 (PINK1). In conclusion, the protective effect of curcumin in cisplatin-induced AKI was associated with the prevention of the alterations in mitochondrial bioenergetics, ultrastructure, redox balance, dynamic, and SIRT3 levels.
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Injúria Renal Aguda/tratamento farmacológico , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Curcumina/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Curcuma/química , Metabolismo Energético/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitofagia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas/genética , Proteínas/metabolismo , Ratos , Ratos Wistar , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
PURPOSE OF REVIEW: Mesoamerican nephropathy (MeN) is an emerging pathophysiological entity of Chronic kidney desease (CKD) not related to traditional risk factors (diabetes and hypertension) that have caused thousands of deaths in Central America, mainly in sugarcane workers. The focus of this review is to discuss the risk factors and probable mechanisms involved in the initiation and progression of this devastating disease. RECENT FINDINGS: Frequent episodes of subclinical Acute kidney injury caused by repetitive heat stress, dehydration, and strenuous work have been regarded as the main risk factors for MeN. The combination of them chronically activates vasopressin, renin angiotensin aldosterone system, and polyol-fructokinase pathway in the kidney. Also, subclinical rhabdomyolysis compound the framework of the disease by exacerbating systemic inflammation and inducing uricosuria. Exposure to nephrotoxins, high fructose intake, and use of NSAIDs could also contribute to further accelerating the progression of the disease. SUMMARY: The evidence supports the notion that recurrent cycles of heat stress, dehydration, and strenuous work may cause CKD. The chronic activation of such mechanisms likely occurs in other conditions of reduced water intake and probably explains why the current management of CKD has not been effective to revert or halt the progression to end-stage CKD.
Assuntos
Injúria Renal Aguda/fisiopatologia , Doenças dos Trabalhadores Agrícolas/fisiopatologia , Rim/fisiopatologia , Insuficiência Renal Crônica/fisiopatologia , Saccharum , Injúria Renal Aguda/etiologia , Doenças dos Trabalhadores Agrícolas/etiologia , Doenças dos Trabalhadores Agrícolas/mortalidade , América Central , Desidratação , Progressão da Doença , Transtornos de Estresse por Calor/etiologia , Transtornos de Estresse por Calor/mortalidade , Transtornos de Estresse por Calor/fisiopatologia , Humanos , Recidiva , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/mortalidade , Fatores de RiscoRESUMO
Five-sixths nephrectomy (5/6NX) is a widely used model to study the mechanisms leading to renal damage in chronic kidney disease (CKD). However, early alterations on renal function, mitochondrial dynamics, and oxidative stress have not been explored yet. Curcumin is an antioxidant that has shown nephroprotection in 5/6NX-induced renal damage. The aim of this study was to explore the effect of curcumin on early mitochondrial alterations induced by 5/6NX in rats. In isolated mitochondria, 5/6NX-induced hydrogen peroxide production was associated with decreased activity of complexes I and V, decreased activity of antioxidant enzymes, alterations in oxygen consumption and increased MDA-protein adducts. In addition, it was found that 5/6NX shifted mitochondrial dynamics to fusion, which was evidenced by increased optic atrophy 1 and mitofusin 1 (Mfn1) and decreased fission 1 and dynamin-related protein 1 expressions. These data were confirmed by morphological analysis and immunoelectron microscopy of Mfn-1. All the above-described mechanisms were prevented by curcumin. Also, it was found that curcumin prevented renal dysfunction by improving renal blood flow and the total antioxidant capacity induced by 5/6NX. Moreover, in glomeruli and proximal tubules 5/6NX-induced superoxide anion production by uncoupled nitric oxide synthase (NOS) and nicotinamide adenine dinucleotide phosphate oxidase (NOX) dependent way, this latter was associated with increased phosphorylation of serine 304 of p47phox subunit of NOX. In conclusion, this study shows that curcumin pretreatment decreases early 5/6NX-induced altered mitochondrial dynamics, bioenergetics, and oxidative stress, which may be associated with the preservation of renal function. © 2016 BioFactors, 43(2):293-310, 2017.