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1.
Adv Physiol Educ ; 48(4): 677-684, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38991037

RESUMEN

Artificial intelligence (AI) has gained massive interest with the public release of the conversational AI "ChatGPT," but it also has become a matter of concern for academia as it can easily be misused. We performed a quantitative evaluation of the performance of ChatGPT on a medical physiology university examination. Forty-one answers were obtained with ChatGPT and compared to the results of 24 students. The results of ChatGPT were significantly better than those of the students; the median (IQR) score was 75% (66-84%) for the AI compared to 56% (43-65%) for students (P < 0.001). The exam success rate was 100% for ChatGPT, whereas 29% (n = 7) of students failed. ChatGPT could promote plagiarism and intellectual laziness among students and could represent a new and easy way to cheat, especially when evaluations are performed online. Considering that these powerful AI tools are now freely available, scholars should take great care to construct assessments that really evaluate student reflection skills and prevent AI-assisted cheating.NEW & NOTEWORTHY The release of the conversational artificial intelligence (AI) ChatGPT has become a matter of concern for academia as it can easily be misused by students for cheating purposes. We performed a quantitative evaluation of the performance of ChatGPT on a medical physiology university examination and observed that ChatGPT outperforms medical students obtaining significantly better grades. Scholars should therefore take great care to construct assessments crafted to really evaluate the student reflection skills and prevent AI-assisted cheating.


Asunto(s)
Inteligencia Artificial , Evaluación Educacional , Estudiantes de Medicina , Humanos , Evaluación Educacional/métodos , Fisiología/educación , Universidades , Masculino , Femenino , Educación de Pregrado en Medicina/métodos
2.
Gynecol Obstet Invest ; 89(4): 284-294, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38373412

RESUMEN

BACKGROUND: d-Chiro-inositol is a natural molecule that, in association with its well-studied isomer myo-inositol, may play a role in treating various metabolic and gynecological disorders. OBJECTIVES: This perspective seeks to explore the mechanisms and functions of d-chiro-inositol, laying the foundations to discuss its use in clinical practice, across dysmetabolism, obesity, and hormonal dysregulation. METHODS: A narrative review of all the relevant papers known to the authors was conducted. OUTCOME: d-Chiro-inositol acts through a variety of mechanisms, acting as an insulin sensitizer, inhibiting the transcription of aromatase, in addition to modulating white adipose tissue/brown adipose tissue transdifferentiation. These different modes of action have potential applications in a variety of therapeutic fields, including PCOS, dysmetabolism, obesity, hypoestrogenic/hyperandrogenic disorders, and bone health. CONCLUSIONS: d-Chiro-inositol mode of action has been studied in detail in recent years, resulting in a clear differentiation between d-chiro-inositol and its isomer myo-inositol. The insulin-sensitizing activities of d-chiro-inositol are well understood; however, its potential applications in other fields, in particular obesity and hyperestrogenic/hypoandrogenic disorders in men and women, represent promising avenues of research that require further clinical study.


Asunto(s)
Inositol , Resistencia a la Insulina , Obesidad , Síndrome del Ovario Poliquístico , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Síndrome del Ovario Poliquístico/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Humanos , Inositol/uso terapéutico , Resistencia a la Insulina/fisiología , Andrógenos/deficiencia , Aromatasa , Estrógenos/deficiencia
4.
Biochimie ; 213: 22-29, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37142118

RESUMEN

Indoxyl sulfate (IS) is a uremic toxin produced by the gut microbiota that commonly accumulates in patients with chronic kidney disease (CKD) and can be harmful. Resveratrol is a polyphenol with properties that attenuate oxidative stress and inflammation. This study aims to evaluate the effect of resveratrol against the damage caused by IS in RAW 264.7 murine macrophages. Cells were treated with 0, 250, 500 and 1000 µmol/L of IS, in the presence of 50 µmol/L of resveratrol. The mRNA and protein expressions of erythroid-related nuclear factor 2 (Nrf2) and nuclear factor kappa-B (NF-κB) were measured using rt-PCR and Western blot analysis, respectively. Malondialdehyde (MDA) and reactive oxygen species (ROS) levels were also analyzed. As a result, it was demonstrated that resveratrol induces the activation of the Nrf2 pathway that enhances cytoprotective response. IS upregulated the NF-κB expression and downregulated the Nrf2 expression. In contrast, resveratrol treatment significantly reduced the MDA and ROS production and inhibited the IS-induced expression of NF-κB in macrophage-like RAW 264.7. In conclusion, resveratrol can mitigate inflammation and oxidative stress caused by uremic toxins produced by the gut microbiota, such as IS.


Asunto(s)
Indicán , FN-kappa B , Humanos , Ratones , Animales , Resveratrol/farmacología , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Indicán/toxicidad , Tóxinas Urémicas , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Inflamación/tratamiento farmacológico , Macrófagos/metabolismo
5.
Life Sci ; 322: 121664, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37023957

RESUMEN

AIMS: Sulforaphane (SFN), a naturally occurring isothiocyanate found in cruciferous vegetables, has received extensive attention as a natural activator of the Nrf2/Keap1 cytoprotective pathway. In this review, a meta-analysis and systematic review of the renoprotective effects of SFN were performed in various preclinical models of kidney diseases. MAIN METHODS: The primary outcome was the impact of SFN on renal function biomarkers (uremia, creatininemia, proteinuria or creatinine clearance) and secondary outcomes were kidney lesion histological indices/kidney injury molecular biomarkers. The effects of SFN were evaluated according to the standardized mean differences (SMDs). A random-effects model was applied to estimate the overall summary effect. KEY FINDINGS: Twenty-five articles (out of 209 studies) were selected from the literature. SFN administration significantly increased creatinine clearance (SMD +1.88 95 % CI: [1.09; 2.68], P < 0.0001, I2 = 0 %) and decreased the plasma creatinine (SMD -1.24, [-1.59; -0.88], P < 0.0001, I2 = 36.0 %) and urea (SMD -3.22 [-4.42, -2.01], P < 0.0001, I2 = 72.4 %) levels. SFN administration (median dose: 2.5 mg/kg, median duration: 3 weeks) significantly decreased urinary protein excretion (SMD -2.20 [-2.68; -1.73], P < 0.0001, I2 = 34.1 %). It further improved two kidney lesion histological indices namely kidney fibrosis (SMD -3.08 [-4.53; -1.63], P < 0.0001, I2 = 73.7 %) and glomerulosclerosis (SMD -2.24 [-2.96; -1.53], P < 0.0001, I2 = 9.7 %) and decreased kidney injury molecular biomarkers (SMD -1.51 [-2.00; -1.02], P < 0.0001, I2 = 0 %). SIGNIFICANCE: These findings provide new insights concerning preclinical strategies for treating kidney disease or kidney failure with SFN supplements and should stimulate interest in clinical evaluations of SFN in patients with kidney disease.


Asunto(s)
Enfermedades Renales , Factor 2 Relacionado con NF-E2 , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Creatinina , Factor 2 Relacionado con NF-E2/metabolismo , Enfermedades Renales/tratamiento farmacológico , Isotiocianatos/farmacología , Isotiocianatos/uso terapéutico , Biomarcadores/metabolismo
7.
Kidney Int ; 102(4): 728-739, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35870642

RESUMEN

Chronic kidney diseasehas been associated with changes in the function and composition of the gut microbiota. The ecosystem of the human gut consists of trillions of microorganisms forming an authentic metabolically active organ that is fueled by nutrients to produce bioactive compounds. These microbiota-derived metabolites may be protective for kidney function (e.g., short-chain fatty acids from fermentation of dietary fibers) or deleterious (e.g., gut-derived uremic toxins such as trimethylamine N-oxide, p-cresyl sulfate, and indoxyl sulfate from fermentation of amino acids). Although diet is the cornerstone of the management of the patient with chronic kidney disease, it remains a relatively underused component of the clinician's armamentarium. In this review, we describe the latest advances in understanding the diet-microbiota crosstalk in the uremic context and how this communication might contribute to chronic kidney disease progression and complications. We then discuss how this knowledge could be harnessed for personalized nutrition strategies to prevent patients with chronic kidney disease progressing tokidney failureand its detrimental consequences.


Asunto(s)
Microbioma Gastrointestinal , Insuficiencia Renal Crónica , Aminoácidos , Dieta/efectos adversos , Fibras de la Dieta , Ingestión de Alimentos , Ecosistema , Ácidos Grasos Volátiles , Humanos , Indicán , Nutrientes , Sulfatos
8.
Nephrol Dial Transplant ; 37(10): 1951-1961, 2022 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-35234930

RESUMEN

BACKGROUND: Chronic kidney disease is an important contributor to morbidity and mortality. 3-methylhistidine (3-MH) is the by-product of actin and myosin degradation reflecting skeletal muscle turnover. Markedly elevated 3-MH levels have been documented in uraemic patients, but the interpretation of high 3-MH concentration in maintenance haemodialysis (MHD) patients remains unclear. Indeed, it is not known whether elevated serum 3-MH levels are a marker of excessive muscle catabolism or a better lean tissue mass. Here, we evaluated the association between serum 3-MH levels and clinical outcomes in these patients. METHODS: Serum 3-MH concentration was measured by reverse-phase liquid chromatography/tandem mass spectrometry in a cohort of MHD patients. We analysed the relationships between various clinical/laboratory indices, lean tissue mass measured by bioimpedance spectroscopy, mortality and cardiovascular (CV) events. RESULTS: Serum 3-MH concentration was positively correlated with serum albumin, normalized protein catabolic rate (nPCR), simplified creatinine index (SCI) and lean tissue mass. Of 291 MHD patients, during a mean follow-up of 847 days, 91 patients died and 101 patients experienced a CV event. Survival was significantly better in patients with high 3-MH concentrations (P = .002). A higher level of 3-MH was also associated with a lower CV mortality and lower incidence of CV events (P = .015 and P < .001, respectively). Low serum 3-MH levels remained significantly associated with CV events but not with mortality after adjustment for demographic, metabolic and CV risk factors. CONCLUSION: Elevated serum 3-MH concentration appears to be a marker of better lean tissue mass and nutritional status. Low serum 3-MH is a robust and independent predictor of CV events in the MHD population.


Asunto(s)
Actinas , Fallo Renal Crónico , Metilhistidinas , Diálisis Renal , Actinas/metabolismo , Biomarcadores/análisis , Biomarcadores/metabolismo , Creatinina , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/terapia , Metilhistidinas/sangre , Metilhistidinas/metabolismo , Albúmina Sérica/análisis , Albúmina Sérica/metabolismo
9.
J Ren Nutr ; 32(2): 234-242, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33888408

RESUMEN

OBJECTIVE: Imbalance between anabolism and catabolism is linked to cachexia and protein-energy wasting (PEW), especially in frail populations such as patients with chronic kidney disease. PEW is responsible of poor outcomes with increased morbidity and mortality. Several causes are involved in PEW such as insulin resistance, acidosis, or hyperparathyroidism. Natriuretic peptides (NPs) have recently been described as activators of resting energy expenditure through the induction of browning of white adipose tissue in rodents with chronic kidney disease. The present study was therefore implemented to investigate whether NPs could be associated with PEW criteria and predict clinical outcomes. METHODS: We quantified serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) in a prospective cohort of 231 patients undergoing maintenance hemodialysis and atrial natriuretic peptide in a subgroup of 35 patients. Body composition parameters were measured with bioimpedance spectroscopy. RESULTS: NT-proBNP was inversely associated with serum albumin, prealbumin, and body mass index and, conversely, positively associated with age and C-reactive protein. NT-proBNP as well as atrial natriuretic peptide were significantly higher in patients with PEW criteria. NT-proBNP was negatively associated with body fat mass. In multiple linear regression, NT-proBNP remained associated with body mass index. Kaplan-Meier analysis revealed a significant correlation between serum NT-proBNP concentrations and all-cause mortality and cardiovascular events. This association remained significant after multivariable Cox regression models adjusted for demographic factors and cardiovascular risk factors. CONCLUSION: Accumulation of NPs seems to be associated with poor nutritional status and reduced survival among hemodialysis patients. Further studies are needed to confirm this association using resting energy expenditure measurement and adipose tissue biopsy.


Asunto(s)
Factor Natriurético Atrial , Insuficiencia Renal Crónica , Caquexia , Femenino , Humanos , Masculino , Péptidos Natriuréticos , Estudios Prospectivos , Diálisis Renal , Insuficiencia Renal Crónica/terapia
11.
Int J Mol Sci ; 22(19)2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34638926

RESUMEN

Myo-inositol (myo-Ins) and D-chiro-inositol (D-chiro-Ins) are natural compounds involved in many biological pathways. Since the discovery of their involvement in endocrine signal transduction, myo-Ins and D-chiro-Ins supplementation has contributed to clinical approaches in ameliorating many gynecological and endocrinological diseases. Currently both myo-Ins and D-chiro-Ins are well-tolerated, effective alternative candidates to the classical insulin sensitizers, and are useful treatments in preventing and treating metabolic and reproductive disorders such as polycystic ovary syndrome (PCOS), gestational diabetes mellitus (GDM), and male fertility disturbances, like sperm abnormalities. Moreover, besides metabolic activity, myo-Ins and D-chiro-Ins deeply influence steroidogenesis, regulating the pools of androgens and estrogens, likely in opposite ways. Given the complexity of inositol-related mechanisms of action, many of their beneficial effects are still under scrutiny. Therefore, continuing research aims to discover new emerging roles and mechanisms that can allow clinicians to tailor inositol therapy and to use it in other medical areas, hitherto unexplored. The present paper outlines the established evidence on inositols and updates on recent research, namely concerning D-chiro-Ins involvement into steroidogenesis. In particular, D-chiro-Ins mediates insulin-induced testosterone biosynthesis from ovarian thecal cells and directly affects synthesis of estrogens by modulating the expression of the aromatase enzyme. Ovaries, as well as other organs and tissues, are characterized by a specific ratio of myo-Ins to D-chiro-Ins, which ensures their healthy state and proper functionality. Altered inositol ratios may account for pathological conditions, causing an imbalance in sex hormones. Such situations usually occur in association with medical conditions, such as PCOS, or as a consequence of some pharmacological treatments. Based on the physiological role of inositols and the pathological implications of altered myo-Ins to D-chiro-Ins ratios, inositol therapy may be designed with two different aims: (1) restoring the inositol physiological ratio; (2) altering the ratio in a controlled way to achieve specific effects.


Asunto(s)
Diabetes Gestacional/tratamiento farmacológico , Inositol/farmacología , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Testosterona/metabolismo , Células Tecales/efectos de los fármacos , Diabetes Gestacional/metabolismo , Femenino , Humanos , Inositol/química , Inositol/metabolismo , Estructura Molecular , Síndrome del Ovario Poliquístico/metabolismo , Embarazo , Transducción de Señal/efectos de los fármacos , Células Tecales/metabolismo
12.
Nephrol Dial Transplant ; 37(1): 1-4, 2021 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-34519782

Asunto(s)
Urea , Uremia , Humanos
13.
Sci Rep ; 11(1): 19184, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34584168

RESUMEN

Despite decades of use of low protein diets (LPD) in the management of chronic kidney disease (CKD), their mechanisms of action are unclear. A reduced production of uremic toxins could contribute to the benefits of LPDs. Aromatic amino-acids (AA) are precursors of major uremic toxins such as p-cresyl sulfate (PCS) and indoxyl sulfate (IS). We hypothesize that a low aromatic amino acid diet (LA-AAD, namely a low intake of tyrosine, tryptophan and phenylalanine) while being normoproteic, could be as effective as a LPD, through the decreased production of uremic toxins. Kidney failure was chemically induced in mice with a diet containing 0.25% (w/w) of adenine. Mice received three different diets for six weeks: normoproteic diet (NPD: 14.7% proteins, aromatic AAs 0.019%), LPD (5% proteins, aromatic AAs 0.007%) and LA-AAD (14% proteins, aromatic AAs 0.007%). Both LPD and LA-AAD significantly reduced proteinuria, kidney fibrosis and inflammation. While LPD only slightly decreased plasma free PCS and free IS compared to NPD; free fractions of both compounds were significantly decreased by LA-AAD. These results suggest that a LA-AAD confers similar benefits of a LPD in delaying the progression of CKD through a reduction in some key uremic toxins production (such as PCS and IS), with a lower risk of malnutrition.


Asunto(s)
Aminoácidos Aromáticos/efectos adversos , Dieta con Restricción de Proteínas/métodos , Riñón/patología , Desnutrición/prevención & control , Insuficiencia Renal Crónica/dietoterapia , Animales , Dieta con Restricción de Proteínas/efectos adversos , Modelos Animales de Enfermedad , Fibrosis , Humanos , Masculino , Desnutrición/etiología , Ratones , Insuficiencia Renal Crónica/patología , Tóxinas Urémicas/metabolismo
14.
Biochimie ; 189: 137-143, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34217821

RESUMEN

Patients with chronic kidney disease (CKD) often exhibit increased level of oxidative stress that contribute to the deterioration of renal function and uremic complications. White adipose tissue (WAT) has been recognized as a major site of production of radical oxygen species (ROS) in the context of metabolic diseases. This study was designed to decipher whether the protein bound uremic toxin p-cresyl-sulfate (p-CS) could contribute to ROS production in WAT and promote oxidative stress. Mouse 3T3-L1 adipocytes were incubated for 2 h in culture medium containing 212 µM p-CS, a concentration chosen to mimic levels encountered in end stage renal disease patients or KCl as a control and intracellular ROS production was measured using the fluorescent probe 5-6-carboxy-2',7'-dichlorodihydrofluorescein diacetate. Oxidative insult was estimated by the measurement of malondialdehyde (MDA) content and glutathione content. The effects of probenecid (1 mM) a potent inhibitor of organic anion transporter, apocynin (1 mM) an inhibitor of NADPH oxidase or common antioxidants such as α-tocopherol (2.5 µM), ascorbate (200 µM), and N-acetylcysteine (500 µM) were further evaluated. p-CS triggered a striking increase in ROS production (+228%, p < 0.01), in MDA content (+214%, p < 0.005) and a decrease in glutathione (-47%, P < 0.01). Pre-treatment of cells with probenecid, apocynin or antioxidants prevented the p-CS induced ROS production and oxidative insults. These results suggest that in uremic state, the intracellular accumulation of p-CS in adipose cells could contribute, through an activation of NADPH oxidase, to the redox imbalance often reported in CKD patients.


Asunto(s)
Adipocitos/metabolismo , Cresoles/farmacología , Peroxidación de Lípido/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Insuficiencia Renal Crónica/metabolismo , Ésteres del Ácido Sulfúrico/farmacología , Células 3T3-L1 , Animales , Ratones
15.
Perit Dial Int ; 41(4): 423-426, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32873148

RESUMEN

Glucose absorption during peritoneal dialysis (PD) is suspected to promote visceral fat accretion and weight gain in PD patients. The current study was designed to test the impact of glucose-based PD fluids on adipose cell lipolysis and glycogen content. Rat adipose cells, isolated from epididymal fat pad, were exposed to a 30 vol./70 vol. mixture of glucose-based dialysis solutions (containing 1.36% and 3.86% glucose, Physioneal 35®; Baxter) or Krebs-Henseleit buffer for 4 h. Adipose cells were further incubated with laboratory-made solutions containing 1.36% and 3.86% glucose or mannitol as an osmotic control. Baseline and noradrenaline-stimulated lipolysis was measured, and glycogen content assayed. The glucose-based commercial PD fluids as well as the laboratory-manufactured high glucose solutions exacerbated lipolysis in baseline and noradrenaline conditions and increased glycogen stores in adipose cells. Mannitol solutions (1.36% and 3.86%) used as an osmotic control did not produce such effects. This study provides the first evidence that glucose-based dialysis solutions increase basal as well as stimulated lipolysis in adipocytes, an effect that is directly attributable to high concentrations of glucose per se.


Asunto(s)
Diálisis Peritoneal , Adipocitos/metabolismo , Animales , Soluciones para Diálisis/efectos adversos , Glucosa , Glucógeno/metabolismo , Humanos , Lipólisis , Diálisis Peritoneal/efectos adversos , Ratas
16.
Toxins (Basel) ; 12(12)2020 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-33255454

RESUMEN

BACKGROUND: Chronic kidney disease (CKD) is a renal disorder characterized by the accumulation of uremic toxins with limited strategies to reduce their concentrations. A large amount of data supports the pivotal role of intestinal microbiota in CKD complications and as a major source of uremic toxins production. Here, we explored whether fecal microbiota transplantation (FMT) could be attenuated in metabolic complication and uremic toxin accumulation in mice with CKD. METHODS: Kidney failure was chemically induced by a diet containing 0.25% (w/w) of adenine for four weeks. Mice were randomized into three groups: control, CKD and CKD + FMT groups. After four weeks, CKD mice underwent fecal microbiota transplantation (FMT) from healthy mice or phosphate buffered saline as control. The gut microbiota structure, uremic toxins plasmatic concentrations, and metabolic profiles were explored three weeks after transplantation. RESULTS: Associated with the increase of alpha diversity, we observed a noticeable improvement of gut microbiota disturbance, after FMT treatment. FMT further decreased p-cresyl sulfate accumulation and improved glucose tolerance. There was no change in kidney function. CONCLUSIONS: These data indicate that FMT limited the accumulation of uremic toxins issued from intestinal cresol pathway by a beneficial effect on gut microbiota diversity. Further studies are needed to investigate the FMT efficiency, the timing and feces amount for the transplantation before, to become a therapeutic option in CKD patients.


Asunto(s)
Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/terapia , Uremia/terapia , Animales , Biomarcadores/metabolismo , ADN Bacteriano , Modelos Animales de Enfermedad , Heces/microbiología , Intolerancia a la Glucosa/complicaciones , Intolerancia a la Glucosa/terapia , Riñón/metabolismo , Masculino , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/terapia , Metaboloma , Ratones , Ratones Endogámicos C57BL , ARN Ribosómico 16S , Orina/química
17.
Toxins (Basel) ; 12(9)2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32899405

RESUMEN

Lipid aldehydes originating from the peroxidation of n-3 and n-6 polyunsaturated fatty acids are increased in hemodialysis (HD) patients, a process already known to promote oxidative stress. However, data are lacking for patients with chronic kidney disease (CKD) before the initiation of HD. We prospectively evaluated the changes of plasma concentrations of two major lipid aldehydes, 4-HHE and 4-HNE, according to the decrease of glomerular filtration rate (GFR) in 40 CKD and 13 non-CKD participants. GFR was measured by inulin or iohexol clearance. Thus, 4-hydroxy-2-nonenal (4-HNE) and 4-hydroxy-2-hexenal (4-HHE) were quantitated in plasma by gas chromatography coupled with mass spectrometry and their covalent adducts on proteins were quantified by immunoblotting. On the one hand, 4-HHE plasma concentration increased from CKD stage I-II to CKD stage IV-V compared to non-CKD patients (4.5-fold higher in CKD IV-V, p < 0.005). On the other hand, 4-HNE concentration only increased in CKD stage IV-V patients (6.2-fold, p < 0.005). The amount of covalent adducts of 4-HHE on plasma protein was 9.5-fold higher in CKD patients than in controls (p < 0.005), while no difference was observed for 4-HNE protein adducts. Plasma concentrations of 4-HNE and 4-HHE are increased in CKD IV-V patients before the initiation of hemodialysis.


Asunto(s)
Aldehídos/sangre , Biomarcadores/sangre , Peroxidación de Lípido , Estrés Oxidativo , Insuficiencia Renal Crónica/sangre , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Cromatografía de Gases y Espectrometría de Masas , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/fisiopatología , Regulación hacia Arriba
18.
Kidney Int ; 98(3): 663-672, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32739210

RESUMEN

Protein energy wasting is a common feature of patients with chronic kidney disease (CKD) and is associated with poor outcomes. Protein energy wasting and cachexia, a severe form of protein energy wasting, are characterized by increased resting energy expenditure but the underlying mechanisms are unclear. Browning corresponds to the activation of inducible brown adipocytes in white adipose tissue and occurs in states of cachexia associated with hypermetabolic disease such as cancer. Here we tested the hypothesis that CKD-associated protein energy wasting could result from browning activation as a direct effect of the uremic environment on adipocytes. In a murine model of CKD (5/6 nephrectomy), there was increased resting energy expenditure, expression of uncoupling protein 1 (a thermogenic protein uncoupling oxidative phosphorylation in mitochondria) and citrate synthase activity (a proxy of mitochondrial density in white adipose tissue). Mice with CKD also exhibited increased levels of atrial natriuretic peptide, a well known activator of browning. The incubation of primary adipose cells with plasma from patients receiving dialysis treatment and having signs of protein energy wasting led to an increased synthesis of uncoupling protein 1. Similarly, primary adipose cells exposed to atrial natriuretic peptide at concentrations relevant of CKD led to a significant increase of uncoupling protein 1 content. Thus, accumulation of cardiac natriuretic peptides during CKD could contribute to the browning of white adipose tissue and protein energy wasting.


Asunto(s)
Caquexia , Insuficiencia Renal Crónica , Tejido Adiposo Blanco/metabolismo , Animales , Caquexia/metabolismo , Metabolismo Energético , Humanos , Ratones , Péptidos Natriuréticos/metabolismo , Insuficiencia Renal Crónica/metabolismo , Proteína Desacopladora 1/metabolismo
19.
J Am Soc Nephrol ; 31(7): 1462-1477, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32518085

RESUMEN

BACKGROUND: CKD is associated with increased oxidative stress that correlates with occurrence of cardiovascular events. Modifications induced by increased oxidative stress particularly affect circulating lipoproteins such as HDL that exhibit antiatheromatous and antithrombotic properties in vitro. METHODS: To explore the specific role of oxidative modifications of HDL in CKD and their effect on the platelet-targeting antiaggregant properties of HDL, we used a CKD (5/6 nephrectomy) rabbit model. For ex vivo assessment of the antiaggregant properties of HDL, we collected blood samples from 15 healthy volunteers, 25 patients on hemodialysis, and 20 on peritoneal dialysis. We analyzed malondialdehyde, 4-hydroxynonenal (HNE), and 4-hydroxy-2-hexenal protein adduct levels. Platelet aggregation and activation were assessed by aggregometry, thromboxane B2 assay, or FACS. We modified HDL from controls by incubating it overnight at 37°C with 100 µM of HNE. RESULTS: HDL from CKD rabbits and patients on hemodialysis had HNE adducts. The percentage of platelet aggregation or activation induced by collagen was significantly higher when platelets were incubated with HDL from CKD rabbit and hemodialysis groups than with HDL from the control group. In both rabbits and humans, platelet aggregation and activation were significantly higher in the presence of HNE-modified HDL than with HDL from their respective controls. Incubation of platelets with a blocking antibody directed against CD36 or with a pharmacologic inhibitor of SRC kinases restored the antiaggregative phenotype in the presence of HDL from CKD rabbits, patients on hemodialysis and peritoneal dialysis, and HNE-modified HDL. CONCLUSIONS: HDL from CKD rabbits and patients on hemodialysis exhibited an impaired ability to inhibit platelet aggregation, suggesting that altered HDL properties may contribute to the increased cardiovascular risk in this population.


Asunto(s)
Aldehídos/sangre , Lipoproteínas HDL/sangre , Lipoproteínas HDL/farmacología , Estrés Oxidativo , Agregación Plaquetaria/efectos de los fármacos , Insuficiencia Renal Crónica/sangre , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos/farmacología , Plaquetas , Antígenos CD36/inmunología , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Oxidación-Reducción , Diálisis Peritoneal , Fosforilación , Carbonilación Proteica , Inhibidores de Proteínas Quinasas/farmacología , Conejos , Insuficiencia Renal Crónica/terapia , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismo
20.
Trends Endocrinol Metab ; 31(6): 435-447, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32396844

RESUMEN

This review details the physiologic roles of two insulin sensitizers, myo-inositol (MI) and d-chiro-inositol (DCI). In the human ovary, MI is a second messenger of follicle-stimulating hormone (FSH) and DCI is an aromatase inhibitor. These activities allow a treatment for polycystic ovary syndrome (PCOS) to be defined based on the combined administration of MI and DCI, where the best MI:DCI ratio is 40:1. Moreover, MI enhances the effect of metformin and clomiphene on the fertility of PCOS women seeking pregnancy. As impaired intestinal transport may lead to unsuccessful inositol treatment, we also discuss new data on the use of alpha-lactalbumin to boost inositol absorption. Overall, the physiological activities of MI and DCI dictate the dosages and timing of inositol supplementation in the treatment of PCOS.


Asunto(s)
Inositol/farmacología , Inositol/fisiología , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Complejo Vitamínico B/farmacología , Animales , Femenino , Humanos , Inositol/administración & dosificación , Complejo Vitamínico B/administración & dosificación
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