Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 136
Filtrar
1.
Biochim Biophys Acta Gen Subj ; 1868(10): 130684, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39084330

RESUMEN

It is well-established that dysfunction of megalin-mediated albumin endocytosis by proximal tubule epithelial cells (PTECs) and the activation of the Renin-Angiotensin System (RAS) play significant roles in the development of Diabetic Kidney Disease (DKD). However, the precise correlation between these factors still requires further investigation. In this study, we aimed to elucidate the potential role of angiotensin II (Ang II), a known effector of RAS, as the mediator of albumin endocytosis dysfunction induced by high glucose (HG) in PTECs. To achieve this, we utilized LLC-PK1 and HK-2 cells, which are well-established in vitro models of PTECs. Using albumin-FITC or DQ-albumin as tracers, we observed that incubation of LLC-PK1 and HK-2 cells with HG (25 mM for 48 h) significantly reduced canonical receptor-mediated albumin endocytosis, primarily due to the decrease in megalin expression. HG increased the concentration of Ang II in the LLC-PK1 cell supernatant, a phenomenon associated with an increase in angiotensin-converting enzyme (ACE) expression and a decrease in prolyl carboxypeptidase (PRCP) expression. ACE type 2 (ACE2) expression remained unchanged. To investigate the potential impact of Ang II on HG effects, the cells were co-incubated with angiotensin receptor inhibitors. Only co-incubation with 10-7 M losartan (an antagonist for type 1 angiotensin receptor, AT1R) attenuated the inhibitory effect of HG on albumin endocytosis, as well as megalin expression. Our findings contribute to understanding the genesis of tubular albuminuria observed in the early stages of DKD, which involves the activation of the Ang II/AT1R axis by HG.


Asunto(s)
Albúminas , Angiotensina II , Endocitosis , Células Epiteliales , Glucosa , Túbulos Renales Proximales , Receptor de Angiotensina Tipo 1 , Endocitosis/efectos de los fármacos , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Túbulos Renales Proximales/efectos de los fármacos , Angiotensina II/farmacología , Glucosa/metabolismo , Glucosa/farmacología , Receptor de Angiotensina Tipo 1/metabolismo , Animales , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Humanos , Albúminas/metabolismo , Porcinos , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Sistema Renina-Angiotensina/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Línea Celular , Losartán/farmacología
2.
Nat Commun ; 15(1): 5833, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992033

RESUMEN

Arthropod-borne viruses represent a crucial public health threat. Current arboviral serology assays are either labor intensive or incapable of distinguishing closely related viruses, and many zoonotic arboviruses that may transition to humans lack any serologic assays. In this study, we present a programmable phage display platform, ArboScan, that evaluates antibody binding to overlapping peptides that represent the proteomes of 691 human and zoonotic arboviruses. We confirm that ArboScan provides detailed antibody binding information from animal sera, human sera, and an arthropod blood meal. ArboScan identifies distinguishing features of antibody responses based on exposure history in a Colombian cohort of Zika patients. Finally, ArboScan details epitope level information that rapidly identifies candidate epitopes with potential protective significance. ArboScan thus represents a resource for characterizing human and animal arbovirus antibody responses at cohort scale.


Asunto(s)
Anticuerpos Antivirales , Arbovirus , Humanos , Arbovirus/inmunología , Arbovirus/aislamiento & purificación , Animales , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Péptidos/inmunología , Péptidos/química , Infección por el Virus Zika/virología , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/sangre , Virus Zika/inmunología , Epítopos/inmunología , Pruebas Serológicas/métodos , Infecciones por Arbovirus/virología , Infecciones por Arbovirus/inmunología , Proteoma , Colombia , Femenino , Biblioteca de Péptidos , Técnicas de Visualización de Superficie Celular , Masculino
3.
J Pediatr ; 271: 114042, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38570031

RESUMEN

OBJECTIVE: The objective of this study was to examine the association of cardiorespiratory events, including apnea, periodic breathing, intermittent hypoxemia (IH), and bradycardia, with late-onset sepsis for extremely preterm infants (<29 weeks of gestational age) on vs off invasive mechanical ventilation. STUDY DESIGN: This is a retrospective analysis of data from infants enrolled in Pre-Vent (ClinicalTrials.gov identifier NCT03174301), an observational study in 5 level IV neonatal intensive care units. Clinical data were analyzed for 737 infants (mean gestational age: 26.4 weeks, SD 1.71). Monitoring data were available and analyzed for 719 infants (47 512 patient-days); of whom, 109 had 123 sepsis events. Using continuous monitoring data, we quantified apnea, periodic breathing, bradycardia, and IH. We analyzed the relationships between these daily measures and late-onset sepsis (positive blood culture >72 hours after birth and ≥5-day antibiotics). RESULTS: For infants not on a ventilator, apnea, periodic breathing, and bradycardia increased before sepsis diagnosis. During times on a ventilator, increased sepsis risk was associated with longer events with oxygen saturation <80% (IH80) and more bradycardia events before sepsis. IH events were associated with higher sepsis risk but did not dynamically increase before sepsis, regardless of ventilator status. A multivariable model including postmenstrual age, cardiorespiratory variables (apnea, periodic breathing, IH80, and bradycardia), and ventilator status predicted sepsis with an area under the receiver operator characteristic curve of 0.783. CONCLUSION: We identified cardiorespiratory signatures of late-onset sepsis. Longer IH events were associated with increased sepsis risk but did not change temporally near diagnosis. Increases in bradycardia, apnea, and periodic breathing preceded the clinical diagnosis of sepsis.


Asunto(s)
Apnea , Bradicardia , Hipoxia , Recien Nacido Extremadamente Prematuro , Sepsis , Humanos , Bradicardia/epidemiología , Bradicardia/etiología , Apnea/epidemiología , Estudios Retrospectivos , Recién Nacido , Hipoxia/complicaciones , Femenino , Masculino , Sepsis/complicaciones , Sepsis/epidemiología , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/diagnóstico , Respiración Artificial , Unidades de Cuidado Intensivo Neonatal , Edad Gestacional
4.
Biochim Biophys Acta Mol Basis Dis ; 1870(5): 167155, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38579939

RESUMEN

Tubular proteinuria is a common feature in COVID-19 patients, even in the absence of established acute kidney injury. SARS-CoV-2 spike protein (S protein) was shown to inhibit megalin-mediated albumin endocytosis in proximal tubule epithelial cells (PTECs). Angiotensin-converting enzyme type 2 (ACE2) was not directly involved. Since Toll-like receptor 4 (TLR4) mediates S protein effects in various cell types, we hypothesized that TLR4 could be participating in the inhibition of PTECs albumin endocytosis elicited by S protein. Two different models of PTECs were used: porcine proximal tubule cells (LLC-PK1) and human embryonic kidney cells (HEK-293). S protein reduced Akt activity by specifically inhibiting of threonine 308 (Thr308) phosphorylation, a process mediated by phosphoinositide-dependent kinase 1 (PDK1). GSK2334470, a PDK1 inhibitor, decreased albumin endocytosis and megalin expression mimicking S protein effect. S protein did not change total TLR4 expression but decreased its surface expression. LPS-RS, a TLR4 antagonist, also counteracted the effects of the S protein on Akt phosphorylation at Thr308, albumin endocytosis, and megalin expression. Conversely, these effects of the S protein were replicated by LPS, an agonist of TLR4. Incubation of PTECs with a pseudovirus containing S protein inhibited albumin endocytosis. Null or VSV-G pseudovirus, used as control, had no effect. LPS-RS prevented the inhibitory impact of pseudovirus containing the S protein on albumin endocytosis but had no influence on virus internalization. Our findings demonstrate that the inhibitory effect of the S protein on albumin endocytosis in PTECs is mediated through TLR4, resulting from a reduction in megalin expression.


Asunto(s)
Endocitosis , Túbulos Renales Proximales , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Receptor Toll-Like 4 , Receptor Toll-Like 4/metabolismo , Endocitosis/efectos de los fármacos , Humanos , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/virología , Animales , Glicoproteína de la Espiga del Coronavirus/metabolismo , SARS-CoV-2/metabolismo , Células HEK293 , Porcinos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosforilación , COVID-19/metabolismo , COVID-19/virología , COVID-19/patología , Albúminas/metabolismo , Células LLC-PK1 , Células Epiteliales/metabolismo , Células Epiteliales/virología
5.
Food Res Int ; 176: 113831, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38163729

RESUMEN

Artisanal cheese from Serra Geral, Minas Gerais, Brazil, stands out for its cultural asset and socio-economic relevance. However, standards of identity and quality and the peculiar terroir associated with the edaphoclimatic conditions have not been established. Therefore, the production flow diagram and the physico-chemical and microbiological quality of the raw milk, pingo (natural starter culture), production benches, water and fresh cheese were investigated for the first time. In addition, lactic acid bacteria (LAB) from cheese and its production environment were identified by MALDI-TOF. For that, 12 cheese making facilities were selected. The raw milk and pingo showed adequate physico-chemical characteristics for cheesemaking; however, high microbial counts were found. In the water, total and thermotolerant coliforms were also identified. The fresh cheeses were classified as 'high moisture and fat' and 'soft mass'. Most physico-chemical parameters were satisfactory; however, there were high counts of total coliforms, Staphylococcus spp. and coagulase-positive staphylococci. There were high counts of LAB in the raw milk, pingo, bench surface and fresh cheese. A total of 84 microbial biotypes from MRS agar were isolated. Lactococcus lactis was the predominant LAB, followed by Lactococcus garvieae. Leuconostoc mesenteroides (benches), Leuconostoc pseudomesenteroides (fresh cheese), and Enterococcus faecium (pingo) were identified sporadically. These results indicate the risks to public health associated with the consumption of the fresh cheese, and measures to improve its safety are needed.


Asunto(s)
Queso , Lactobacillales , Lactococcus lactis , Animales , Queso/análisis , Leche/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Brasil , Microbiología de Alimentos , Agua
6.
Pediatr Crit Care Med ; 25(1): e41-e46, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37462429

RESUMEN

OBJECTIVE: To determine the association of venovenous extracorporeal membrane oxygenation (VV-ECMO) initiation with changes in vasoactive-inotropic scores (VISs) in children with pediatric acute respiratory distress syndrome (PARDS) and cardiovascular instability. DESIGN: Retrospective cohort study. SETTING: Single academic pediatric ECMO center. PATIENTS: Children (1 mo to 18 yr) treated with VV-ECMO (2009-2019) for PARDS with need for vasopressor or inotropic support at ECMO initiation. MEASUREMENTS AND MAIN RESULTS: Arterial blood gas values, VIS, mean airway pressure (mPaw), and oxygen saturation (Sp o2 ) values were recorded hourly relative to the start of ECMO flow for 24 hours pre-VV-ECMO and post-VV-ECMO cannulation. A sharp kink discontinuity regression analysis clustered by patient tested the difference in VISs and regression line slopes immediately surrounding cannulation. Thirty-two patients met inclusion criteria: median age 6.6 years (interquartile range [IQR] 1.5-11.7), 22% immunocompromised, and 75% had pneumonia or sepsis as the cause of PARDS. Pre-ECMO characteristics included: median oxygenation index 45 (IQR 35-58), mPaw 32 cm H 2o (IQR 30-34), 97% on inhaled nitric oxide, and 81% on an advanced mode of ventilation. Median VIS immediately before VV-ECMO cannulation was 13 (IQR 8-25) with an overall increasing VIS trajectory over the hours before cannulation. VISs decreased and the slope of the regression line reversed immediately surrounding the time of cannulation (robust p < 0.0001). There were pre-ECMO to post-ECMO cannulation decreases in mPaw (32 vs 20 cm H 2o , p < 0.001) and arterial P co2 (64.1 vs 50.1 mm Hg, p = 0.007) and increases in arterial pH (7.26 vs 7.38, p = 0.001), arterial base excess (2.5 vs 5.2, p = 0.013), and SpO 2 (91% vs 95%, p = 0.013). CONCLUSIONS: Initiation of VV-ECMO was associated with an immediate and sustained reduction in VIS in PARDS patients with cardiovascular instability. This VIS reduction was associated with decreased mPaw and reduced respiratory and/or metabolic acidosis as well as improved oxygenation.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Insuficiencia Respiratoria , Humanos , Niño , Estudios Retrospectivos , Síndrome de Dificultad Respiratoria/terapia , Insuficiencia Respiratoria/terapia , Arterias
7.
Transplantation ; 108(3): 713-723, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37635282

RESUMEN

BACKGROUND: Outcomes after living-donor liver transplantation (LDLT) at high Model for End-stage Liver Disease (MELD) scores are not well characterized in the United States. METHODS: This was a retrospective cohort study using Organ Procurement and Transplantation Network data in adults listed for their first liver transplant alone between 2002 and 2021. Cox proportional hazards models evaluated the association of MELD score (<20, 20-24, 25-29, and ≥30) and patient/graft survival after LDLT and the association of donor type (living versus deceased) on outcomes stratified by MELD. RESULTS: There were 4495 LDLTs included with 5.9% at MELD 25-29 and 1.9% at MELD ≥30. LDLTs at MELD 25-29 and ≥30 LDLT have substantially increased since 2010 and 2015, respectively. Patient survival at MELD ≥30 was not different versus MELD <20: adjusted hazard ratio 1.67 (95% confidence interval, 0.96-2.88). However, graft survival was worse: adjusted hazard ratio (aHR) 1.69 (95% confidence interval, 1.07-2.68). Compared with deceased-donor liver transplant, LDLT led to superior patient survival at MELD <20 (aHR 0.92; P = 0.024) and 20-24 (aHR 0.70; P < 0.001), equivalent patient survival at MELD 25-29 (aHR 0.97; P = 0.843), but worse graft survival at MELD ≥30 (aHR 1.68, P = 0.009). CONCLUSIONS: Although patient survival remains acceptable, the benefits of LDLT may be lost at MELD ≥30.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Adulto , Humanos , Estados Unidos , Donadores Vivos , Trasplante de Hígado/efectos adversos , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Supervivencia de Injerto , Resultado del Tratamiento
8.
Protoplasma ; 261(2): 227-243, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37665420

RESUMEN

Monoterpenes are the main component in essential oils of Lippia alba. In this species, the chemical composition of essential oils varies with genome size: citral (geraniol and neral) is dominant in diploids and tetraploids, and linalool in triploids. Because environmental stress impacts various metabolic pathways, we hypothesized that stress responses in L. alba could alter the relationship between genome size and essential oil composition. Water stress affects the flowering, production, and reproduction of plants. Here, we evaluated the effect of water stress on morphophysiology, essential oil production, and the expression of genes related to monoterpene synthesis in diploid, triploid, and tetraploid accessions of L. alba cultivated in vitro for 40 days. First, using transcriptome data, we performed de novo gene assembly and identified orthologous genes using phylogenetic and clustering-based approaches. The expression of candidate genes related to terpene biosynthesis was estimated by real-time quantitative PCR. Next, we assessed the expression of these genes under water stress conditions, whereby 1% PEG-4000 was added to MS medium. Water stress modulated L. alba morphophysiology at all ploidal levels. Gene expression and essential oil production were affected in triploid accessions. Polyploid accessions showed greater growth and metabolic tolerance under stress compared to diploids. These results confirm the complex regulation of metabolic pathways such as the production of essential oils in polyploid genomes. In addition, they highlight aspects of genotype and environment interactions, which may be important for the conservation of tropical biodiversity.


Asunto(s)
Monoterpenos Acíclicos , Lippia , Aceites Volátiles , Verbenaceae , Lippia/genética , Lippia/química , Triploidía , Deshidratación , Filogenia , Aceites Volátiles/química
9.
Brain Res ; 1822: 148669, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37951562

RESUMEN

Cerebral malaria (CM) pathogenesis is described as a multistep mechanism. In this context, monocytes have been implicated in CM pathogenesis by increasing the sequestration of infected red blood cells to the brain microvasculature. In disease, endothelial activation is followed by reduced monocyte rolling and increased adhesion. Nowadays, an important challenge is to identify potential pro-inflammatory stimuli that can modulate monocytes behavior. Our group have demonstrated that bradykinin (BK), a pro-inflammatory peptide involved in CM, is generated during the erythrocytic cycle of P. falciparum and is detected in culture supernatant (conditioned medium). Herein we investigated the role of BK in the adhesion of monocytes to endothelial cells of blood brain barrier (BBB). To address this issue human monocytic cell line (THP-1) and human brain microvascular endothelial cells (hBMECs) were used. It was observed that 20% conditioned medium from P. falciparum infected erythrocytes (Pf-iRBC sup) increased the adhesion of THP-1 cells to hBMECs. This effect was mediated by BK through the activation of B2 and B1 receptors and involves the increase in ICAM-1 expression in THP-1 cells. Additionally, it was observed that angiotensin-converting enzyme (ACE) inhibitor, captopril, enhanced the effect of both BK and Pf-iRBC sup on THP-1 adhesion. Together these data show that BK, generated during the erythrocytic cycle of P. falciparum, could play an important role in adhesion of monocytes in endothelial cells lining the BBB.


Asunto(s)
Barrera Hematoencefálica , Bradiquinina , Adhesión Celular , Malaria Cerebral , Malaria Falciparum , Plasmodium falciparum , Humanos , Bradiquinina/metabolismo , Adhesión Celular/fisiología , Medios de Cultivo Condicionados/farmacología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/fisiología , Eritrocitos/parasitología , Malaria Cerebral/metabolismo , Malaria Cerebral/parasitología , Malaria Falciparum/metabolismo , Malaria Falciparum/parasitología , Monocitos/fisiología , Plasmodium falciparum/fisiología , Barrera Hematoencefálica/fisiopatología
10.
Sci Adv ; 9(46): eadj1022, 2023 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-37967173

RESUMEN

Although originating from a common Gondwanan flora, the diversity and composition of the floras of Africa and South America have greatly diverged since continental breakup of Africa from South America now having much higher plant species richness. However, the phylogenetic diversity of the floras and what this tells us about their evolution remained unexplored. We show that for a given species richness and considering land surface area, topography, and present-day climate, angiosperm phylogenetic diversity in South America is higher than in Africa. This relationship holds regardless of whether all climatically matched areas or only matched areas in tropical climates are considered. Phylogenetic diversity is high relative to species richness in refugial areas in Africa and in northwestern South America, once the gateway for immigration from the north. While species richness is strongly influenced by massive plant radiations in South America, we detect a pervasive influence of historical processes on the phylogenetic diversity of both the South American and African floras.


Asunto(s)
Magnoliopsida , Filogenia , Magnoliopsida/genética , América del Sur , África , Clima Tropical , Biodiversidad
11.
Biochim Biophys Acta Gen Subj ; 1867(11): 130466, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37742874

RESUMEN

BACKGROUND: Diabetic kidney disease (DKD) is a severe complication of diabetes mellitus (DM). It has been proposed that modifications in the function of proximal tubule epithelial cells (PTECs) precede glomerular damage during the onset of DKD. This study aimed to identify modifications in renal sodium handling in the early stage of DM and its molecular mechanism. METHODS: Streptozotocin (STZ)-induced diabetic BALB/c mice (STZ group) and LLC-PK1 cells, a model of PTECs, were used. All parameters were assessed in the 4th week after an initial injection of STZ. RESULTS: Early stage of DKD was characterized by hyperfiltration and PTEC dysfunction. STZ group exhibited increased urinary sodium excretion due to impairment of tubular sodium reabsorption. This was correlated to a decrease in cortical (Na++K+)ATPase (NKA) α1 subunit expression and enzyme activity and an increase in O-GlcNAcylation. RNAseq analysis of patients with DKD revealed an increase in expression of the glutamine-fructose aminotransferase (GFAT) gene, a rate-limiting step of hexosamine biosynthetic pathway, and a decrease in NKA expression. Incubation of LLC-PK1 cells with 10 µM thiamet G, an inhibitor of O-GlcNAcase, reduced the expression and activity of NKA and increased O-GlcNAcylation. Furthermore, 6-diazo-5-oxo-L-norleucine (DON), a GFAT inhibitor, or dapagliflozin, an SGLT2 inhibitor, avoided the inhibitory effect of HG on expression and activity of NKA associated with the decrease in O-GlcNAcylation. CONCLUSION: Our results show that the impairment of tubular sodium reabsorption, in the early stage of DM, is due to SGLT2-mediated HG influx in PTECs, increase in O-GlcNAcylation and reduction in NKA expression and activity.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Ratones , Porcinos , Animales , Humanos , Túbulos Renales Proximales/metabolismo , Riñón/metabolismo , Nefropatías Diabéticas/metabolismo , Sodio/metabolismo , Adenosina Trifosfatasas/metabolismo , Diabetes Mellitus/metabolismo
12.
Front Pharmacol ; 14: 1194816, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37484026

RESUMEN

Introduction: Rapamycin is an immunosuppressor that acts by inhibiting the serine/threonine kinase mechanistic target of rapamycin complex 1. Therapeutic use of rapamycin is limited by its adverse effects. Proteinuria is an important marker of kidney damage and a risk factor for kidney diseases progression and has been reported in patients and animal models treated with rapamycin. However, the mechanism underlying proteinuria induced by rapamycin is still an open matter. In this work, we investigated the effects of rapamycin on parameters of renal function and structure and on protein handling by proximal tubule epithelial cells (PTECs). Methods: Healthy BALB/c mice were treated with 1.5 mg/kg rapamycin by oral gavage for 1, 3, or 7 days. At the end of each treatment, the animals were kept in metabolic cages and renal function and structural parameters were analyzed. LLC-PK1 cell line was used as a model of PTECs to test specific effect of rapamycin. Results: Rapamycin treatment did not change parameters of glomerular structure and function. Conversely, there was a transient increase in 24-h proteinuria, urinary protein to creatinine ratio (UPCr), and albuminuria in the groups treated with rapamycin. In accordance with these findings, rapamycin treatment decreased albumin-fluorescein isothiocyanate uptake in the renal cortex. This effect was associated with reduced brush border expression and impaired subcellular distribution of megalin in PTECs. The effect of rapamycin seems to be specific for albumin endocytosis machinery because it did not modify renal sodium handling or (Na++K+)ATPase activity in BALB/c mice and in the LLC-PK1 cell line. A positive Pearson correlation was found between megalin expression and albumin uptake while an inverse correlation was shown between albumin uptake and UPCr or 24-h proteinuria. Despite its effect on albumin handling in PTECs, rapamycin treatment did not induce tubular injury measured by interstitial space and collagen deposition. Conclusion: These findings suggest that proteinuria induced by rapamycin could have a tubular rather than a glomerular origin. This effect involves a specific change in protein endocytosis machinery. Our results open new perspectives on understanding the undesired effect of proteinuria generated by rapamycin.

13.
Biochim Biophys Acta Gen Subj ; 1867(4): 130314, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36693453

RESUMEN

Subclinical acute kidney injury (subAKI) is characterized by tubule-interstitial injury without significant changes in glomerular function. SubAKI is associated with the pathogenesis and progression of acute and chronic kidney diseases. Currently, therapeutic strategies to treat subAKI are limited. The use of gold nanoparticles (AuNPs) has shown promising benefits in different models of diseases. However, their possible effects on subAKI are still unknown. Here, we investigated the effects of AuNPs on a mouse model of subAKI. Animals with subAKI showed increased functional and histopathologic markers of tubular injury. There were no changes in glomerular function and structure. The animals with subAKI also presented an inflammatory profile demonstrated by activation of Th1 and Th17 cells in the renal cortex. This phenotype was associated with decreased megalin-mediated albumin endocytosis and expression of proximal tubular megalin. AuNP treatment prevented tubule-interstitial injury induced by subAKI. This effect was associated with a shift to an anti-inflammatory Th2 response. Furthermore, AuNP treatment preserved megalin-mediated albumin endocytosis in vivo and in vitro. AuNPs were not nephrotoxic in healthy mice. These results suggest that AuNPs have a protective effect in the tubule-interstitial injury observed in subAKI, highlighting a promising strategy as a future antiproteinuric treatment.


Asunto(s)
Lesión Renal Aguda , Nanopartículas del Metal , Ratones , Animales , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Oro/farmacología , Túbulos Renales Proximales , Modelos Animales de Enfermedad , Proteinuria/metabolismo , Proteinuria/patología , Albúminas/metabolismo , Lesión Renal Aguda/metabolismo
14.
Transplantation ; 107(7): 1524-1534, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36695564

RESUMEN

BACKGROUND: Prior studies are inconsistent regarding the impact of antibody induction therapy on outcomes after liver transplantation (LT) for hepatocellular carcinoma (HCC). METHODS: Adults transplanted with HCC exception priority were identified from February 27, 2002, to March 31, 2019, using the United Network for Organ Sharing database. Time-to-event analyses evaluated the association of antibody induction therapy (none, nondepleting induction [NDI], depleting induction [DI]) with overall post-LT patient survival and HCC recurrence. Separate multivariable models adjusted for tumor characteristics on either last exception or on explant. The interaction of induction and maintenance regimen at LT discharge was investigated. RESULTS: Among 22 535 LTs for HCC, 17 688 (78.48%) received no antibody induction, 2984 (13.24%) NDI, and 1863 (8.27%) DI. Minimal differences in patient and tumor characteristics were noted between induction groups, and there was significant center variability in practices. NDI was associated with improved survival, particularly when combined with a calcineurin inhibitor (CNI) and antimetabolite (hazard ratio [HR] 0.73 versus no induction plus 3-drug therapy in the last exception model [ P < 0.001]; HR 0.64 in the explant model [ P = 0.011]). The combination of DI with CNI alone was also protective (HR 0.43; P = 0.003). Neither NDI nor DI was associated with tumor recurrence (all P > 0.1). However, increased HCC recurrence was observed with no induction plus CNI monotherapy (HR 1.47, P = 0.019; versus no induction plus 3-drug therapy). CONCLUSIONS: In conclusion, induction immunosuppression was not associated with worse post-LT outcomes in patients transplanted with HCC exception priority. An improvement in survival was possibly observed with NDI.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trasplante de Hígado , Adulto , Humanos , Trasplante de Hígado/efectos adversos , Recurrencia Local de Neoplasia/patología , Terapia de Inmunosupresión , Inhibidores de la Calcineurina , Estudios Retrospectivos
15.
Eur J Pharmacol ; 942: 175521, 2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36681317

RESUMEN

Diabetic kidney disease (DKD) is characterized by progressive impairment of kidney function. It has been postulated that tubule-interstitial injury, associated with tubular albuminuria, precedes glomerular damage in the early stage of DKD. Here, we wanted to determine if the development of tubule-interstitial injury at the early stage of DKD implies modulation of megalin-mediated protein reabsorption in proximal tubule epithelial cells (PTECs) by SGLT2-dependent high glucose influx. Rats with streptozotocin (STZ)-induced diabetes were treated or not with dapagliflozin (DAPA) for 8 weeks. Four experimental groups were generated: (1) CONT, control; (2) DAPA, rats treated with DAPA; (3) STZ, diabetic rats; (4) STZ + DAPA, diabetic rats treated with DAPA. No changes in glomerular structure and function were observed. The STZ group presented proteinuria and albuminuria associated with an increase in the fractional excretion of proteins. A positive correlation between glycemia and proteinuria was found. These phenomena were linked to a decrease in luminal and total megalin expression and, consequently, in albumin reabsorption in PTECs. We also observed tubule-interstitial injury characterized by an increase in urinary tubular injury biomarkers and changes in tubular histomorphometry parameters. In addition, inverse correlations were found between cortical albumin uptake and tubule-interstitial injury or glycemia. All these modifications were attenuated in the STZ + DAPA group. These results suggest that SGLT2-dependent high glucose influx into PTECs promotes a harmful effect on the PTECs, leading to the development of tubular albuminuria and tubule-interstitial injury preceding glomerular damage. These results expand current knowledge on the renoprotective effects of gliflozins.


Asunto(s)
Diabetes Mellitus Experimental , Nefropatías Diabéticas , Ratas , Animales , Nefropatías Diabéticas/metabolismo , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , Albuminuria , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/inducido químicamente , Transportador 2 de Sodio-Glucosa/metabolismo , Proteínas/metabolismo , Albúminas/metabolismo , Glucosa/efectos adversos
16.
Rev. chil. endocrinol. diabetes ; 16(3): 80-86, 2023. ilus, tab
Artículo en Español | LILACS | ID: biblio-1451971

RESUMEN

OBJETIVO: Evaluar el tiempo en rango de glucosa y su asociación con otras medidas del control glicémico establecidas por el consenso internacional del tiempo en rango en usuarios de vida real del sistema flash de monitorización de glucosa FreeStyle LibreTM en Chile. MÉTODOS: Se analizaron los datos provenientes de la base de datos Freestyle Libre™ entre diciembre de 2014 y enero de 2022. Las lecturas se dividieron en 10 grupos (deciles) del mismo tamaño (cada decil contenía aproximadamente 498 usuarios) en función del tiempo en rango. Para cada decil se calculó la media de determinaciones diarias, el promedio de glucosa, la HbA1c, la desviación estándar de glucosa, el coeficiente de variación de la glucosa, el tiempo en rango, el tiempo de glucosa (porcentaje) por encima de 250 mg/dL (TA250), el tiempo de glucosa (porcentaje) por encima de 180 mg/dL (TA180), el tiempo por debajo (porcentaje) de 70 mg/dL (TB70) y el tiempo por debajo (porcentaje) de 54 mg/dL (TB54). RESULTADOS: Desde diciembre de 2014 hasta enero de 2022 hubo 4984 lectores. El grupo con el mayor tiempo en rango mostró significativamente una menor glucosa promedio que el grupo con el tiempo en rango más bajo (decil 1: media 248,3 mg/dL, decil 10: media 113,2 mg/L, diferencia ­135,1 mg/dL, p<0.05). Asimismo, el mayor tiempo en rango se asoció con una menor desviación estándar (decil 1: media 93,7mg/dL, decil 10: media 26,7mg/L, diferencia: -67,0 mg/ dL, p<0,05), menor coeficiente de variación (decil 1: media 37,8%, decil 10: media 23,3%, diferencia: -14,5%, p<0,05), menor TA250 (decil 1: media 46,5%, decil 10: media 0,2%, diferencia: -46,3%, p<0.05), menor TA180 (decil 1: media 73,9%, decil 10: media 3,8%, diferencia: -70,1%, p<0.05), menor TB70 (decil 5: mediana 6,13%, decil 10: mediana 1,70%, diferencia: -4,43%, p<0.05) y menor TB54 (decil 5: mediana 1,79%, decil 10: mediana 0,12%, diferencia: -1,67%, p<0.05). El mayor tiempo en rango se asoció también significativamente con más determinaciones diarias (decil 1: media 11,4, decil 10: media 16,6, diferencia: 5,2, p<0,05). La frecuencia media de las determinaciones entre todos los lectores fue de 14,7 determinaciones diarias. CONCLUSIONES: En los pacientes con diabetes en Chile, el empleo del sistema flash de monitorización demuestra la asociación entre el mayor tiempo en rango, la reducción de la variabilidad de la glucosa y un menor riesgo de hiperglucemias e hipoglicemias y también con un mayor compromiso.


OBJECTIVE: To evaluate glucose time in range and its association with other metrics of glucose control established by the International Consensus on TIR amongst real-life patients using the Flash Glucose Monitoring system FreeStyle LibreTM in Chile. METHODS: Data from the Freestyle Libre™ database between December 2014 and January 2022 were analyzed. Readers were divided into 10 groups (deciles) of the same size (each decile had approximately 498 users) according to time in range. For each decile of time in range, the mean of daily scans, average glucose, estimated HbA1c, glucose standard deviation, glucose coefficient of variation, time in range, glucose time (percentage) above 250 mg/dL (TA250), and glucose time (percentage) above 180 mg/dL (TA180), and the median of glucose time (percentage) below 70 mg/dL (TB70) and glucose time (percentage) below 54 mg/dL (TB54), were calculated. RESULTS: From December 2014 to January 2022, there were 4984 readers. The group with the highest TIR showed significantly lower average glucose than the group with the lowest TIR (decile 1: mean 248.3 mg/dL, decile 10: mean 113.2 mg/L, difference: ­135.1 mg/dL, p<0.05). In addition, more time in range was associated with a lower glucose standard deviation (decile 1: mean 93.7 mg/dL, decile 10: mean 26.7 mg/L, difference: -67.0 mg/dL, p<0.05), lower glucose coefficient of variation (decile 1: mean 37.8%, decile 10: mean 23.3%, difference: -14.5%, p<0.05), lower TA250 (decile 1: mean 46.5%, decile 10: mean 0.2%, difference: -46.3%, p<0.05),lower TA180 (decile 1: mean 73.9%, decile 10: mean 3.8%, difference: -70.1%, p<0.05), lower TB70 (decile 5: median 6.13%, decile 10: median 1.70%, difference: -4.43%, p<0.05) and lower TB54 (decile 5: median 1.79%, decile 10: median 0.12%, difference: -1.67%, p<0.05). Greater TIR was also associated with significantly more daily scans (decile 1: mean 11.4, decile 10: mean 16.6, difference: 5.2, p<0.05). Mean scan frequency amongst all readers was 14.7 daily scans. CONCLUSIONS: In patients with diabetes from Chile, the use of the flash glucose monitoring system demonstrates the association between greater TIR, reduced glucose variability, and reduced risk of hyperglycemia and hypoglycemia, and also its association with greater engagement.


Asunto(s)
Humanos , Automonitorización de la Glucosa Sanguínea/métodos , Diabetes Mellitus , Control Glucémico/métodos , Factores de Tiempo , Glucemia , Chile , Cooperación del Paciente , Líquido Extracelular , Exactitud de los Datos
17.
Int J Mol Sci ; 23(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36430671

RESUMEN

Since the outbreak of COVID-19 disease, a bidirectional interaction between kidney disease and the progression of COVID-19 has been demonstrated. Kidney disease is an independent risk factor for mortality of patients with COVID-19 as well as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leading to the development of acute kidney injury (AKI) and chronic kidney disease (CKD) in patients with COVID-19. However, the detection of kidney damage in patients with COVID-19 may not occur until an advanced stage based on the current clinical blood and urinary examinations. Some studies have pointed out the development of subclinical acute kidney injury (subAKI) syndrome with COVID-19. This syndrome is characterized by significant tubule interstitial injury without changes in the estimated glomerular filtration rate. Despite the complexity of the mechanism(s) underlying the development of subAKI, the involvement of changes in the protein endocytosis machinery in proximal tubule (PT) epithelial cells (PTECs) has been proposed. This paper focuses on the data relating to subAKI and COVID-19 and the role of PTECs and their protein endocytosis machinery in its pathogenesis.


Asunto(s)
Lesión Renal Aguda , COVID-19 , Insuficiencia Renal Crónica , Humanos , COVID-19/complicaciones , SARS-CoV-2 , Lesión Renal Aguda/metabolismo , Insuficiencia Renal Crónica/metabolismo , Túbulos Renales Proximales/metabolismo
18.
Brachytherapy ; 21(6): 823-832, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36192312

RESUMEN

PURPOSE: We report the feasibility, experience, and early outcomes of the combined intracavitary and interstitial dedicated applicator using the Kelowna GYN template (Varian, Palo Alto, CA). METHODS AND MATERIALS: The Kelowna GYN template is CT compatible and used for the treatment of gynecologic cancers. In cases with patients that have an intact uterus, a modified applicator system using the Kelowna GYN template and a 3D printed adapter piece allows for compatibility with an intrautaerine tandem. RESULTS: We reviewed the treatment course of 23 patients comprising of 86 fractions of HDR treatment. Median D90 for cervical tumors (n = 7) was 82.4 Gy (range 77.7-92.6); for postoperative cervical tumors (n = 2) was 73.9 Gy (range 72.0-5.8); for vaginal tumors (n = 4) was 85.8 Gy (range 79.8-88.1); for recurrent endometrial (n = 10) was 86.9 Gy (range 74.8-103.2). Median EQD2 D2cc for bladder was 72.4 Gy (range 47.7-99.4), for rectum was 61.2 Gy (range 52.4-80.6), and for sigmoid colon of 50.5 Gy (44.3-66.9). At a median follow-up of 12 months, 2 patients had a local recurrence. Two patients had distant recurrence: one with carcinomatosis at 6 months, and one with pulmonary metastases at 3 months. No patients had late grade three toxicities. CONCLUSIONS: Our single institutional experience supports the use of the Kelowna template as a robust system as a combined IC-IS applicator resulting in versatile and reproducible implants for a variety of gynecologic malignancies.


Asunto(s)
Braquiterapia , Neoplasias de los Genitales Femeninos , Neoplasias del Cuello Uterino , Femenino , Humanos , Braquiterapia/métodos , Neoplasias de los Genitales Femeninos/radioterapia , Dosificación Radioterapéutica , Neoplasias del Cuello Uterino/radioterapia , Neoplasias del Cuello Uterino/patología , Resultado del Tratamiento , Planificación de la Radioterapia Asistida por Computador/métodos
19.
Biochim Biophys Acta Mol Basis Dis ; 1868(12): 166496, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-35863591

RESUMEN

Patients with COVID-19 have high prevalence of albuminuria which is used as a marker of progression of renal disease and is associated with severe COVID-19. We hypothesized that SARS-CoV-2 spike protein (S protein) could modulate albumin handling in proximal tubule epithelial cells (PTECs) and, consequently contribute to the albuminuria observed in patients with COVID-19. In this context, the possible effect of S protein on albumin endocytosis in PTECs was investigated. Two PTEC lines were used: HEK-293A and LLC-PK1. Incubation of both cell types with S protein for 16 h inhibited albumin uptake at the same magnitude. This effect was associated with canonical megalin-mediated albumin endocytosis because: (1) DQ-albumin uptake, a marker of the lysosomal degradation pathway, was reduced at a similar level compared with fluorescein isothiocyanate (FITC)-albumin uptake; (2) dextran-FITC uptake, a marker of fluid-phase endocytosis, was not changed; (3) cell viability and proliferation were not changed. The inhibitory effect of S protein on albumin uptake was only observed when it was added at the luminal membrane, and it did not involve the ACE2/Ang II/AT1R axis. Although both cells uptake S protein, it does not seem to be required for modulation of albumin endocytosis. The mechanism underlying the inhibition of albumin uptake by S protein encompasses a decrease in megalin expression without changes in megalin trafficking and stability. These results reveal a possible mechanism to explain the albuminuria observed in patients with COVID-19.


Asunto(s)
COVID-19 , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad , Albúminas/metabolismo , Albúminas/farmacología , Albuminuria/metabolismo , Enzima Convertidora de Angiotensina 2 , Células Cultivadas , Dextranos/farmacología , Endocitosis/fisiología , Células Epiteliales/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Fluoresceína-5-Isotiocianato/farmacología , Humanos , Proteína 2 Relacionada con Receptor de Lipoproteína de Baja Densidad/metabolismo , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus
20.
PLoS One ; 17(5): e0268347, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35550638

RESUMEN

1,8-Cineole is a naturally occurring compound found in essential oils of different plants and has well-known anti-inflammatory and antimicrobial activities. In the present work, we aimed to investigate its potential antimalarial effect, using the following experimental models: (1) the erythrocytic cycle of Plasmodium falciparum; (2) an adhesion assay using brain microvascular endothelial cells; and (3) an experimental cerebral malaria animal model induced by Plasmodium berghei ANKA infection in susceptible mice. Using the erythrocytic cycle of Plasmodium falciparum, we characterized the schizonticidal effect of 1,8-cineole. This compound decreased parasitemia in a dose-dependent manner with a half maximal inhibitory concentration of 1045.53 ± 63.30 µM. The inhibitory effect of 972 µM 1,8-cineole was irreversible and independent of parasitemia. Moreover, 1,8-cineole reduced the progression of intracellular development of the parasite over 2 cycles, inducing important morphological changes. Ultrastructure analysis revealed a massive loss of integrity of endomembranes and hemozoin crystals in infected erythrocytes treated with 1,8-cineole. The monoterpene reduced the adhesion index of infected erythrocytes to brain microvascular endothelial cells by 60%. Using the experimental cerebral malaria model, treatment of infected mice for 6 consecutive days with 100 mg/kg/day 1,8-cineole reduced cerebral edema with a 50% reduction in parasitemia. Our data suggest a potential antimalarial effect of 1,8-cineole with an impact on the parasite erythrocytic cycle and severe disease.


Asunto(s)
Antimaláricos , Edema Encefálico , Malaria Cerebral , Animales , Antimaláricos/química , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Modelos Animales de Enfermedad , Células Endoteliales , Eucaliptol/farmacología , Malaria Cerebral/tratamiento farmacológico , Malaria Cerebral/parasitología , Malaria Cerebral/prevención & control , Ratones , Ratones Endogámicos C57BL , Monoterpenos/farmacología , Monoterpenos/uso terapéutico , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , Plasmodium berghei , Plasmodium falciparum
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA