Impaired Ischemia-Reperfusion Responses in the Hearts of Aged Male and Female Offspring of Obese Rats.

Maternal obesity predisposes offspring (F1) to cardiovascular disease. To evaluate basal heart function and ischemia-reperfusion (IR) responses in F1 males and females of obese mothers, female Wistar rats (F0) were fed chow or an obesogenic (MO) diet from weaning through pregnancy and lactation. Non-sibling F1 males and females were weaned to chow at postnatal day (PND) 21 and euthanized at PND 550. Offspring of MO mothers (MOF1) rarely survive beyond PND 650. Hearts were immediately isolated from euthanized F1s and subjected to 30 min ischemia with 20 min reperfusion. Retroperitoneal fat, serum triglycerides, glucose, insulin, and insulin resistance were measured. Baseline left ventricular developed pressure (LVDP) was lower in male and female MOF1 than in controls. After global ischemia, LVDP in control (C) male and female F1 recovered 78 and 83%, respectively, while recovery in MO male and female F1 was significantly lower at 28 and 52%, respectively. Following the IR challenge, MO hearts showed a higher functional susceptibility to reperfusion injury, resulting in lower cardiac reserve than controls in both sexes. Female hearts were more resistant to IR. Retroperitoneal fat was increased in male MOF1 vs. CF1. Circulating triglycerides and insulin resistance were increased in male and female MOF1 vs. CF1. These data show that MO programming reduces F1 cardiac reserve associated with age-related insulin resistance in a sex-specific manner.

Anandamide and WIN 55212-2 Afford Protection in Rat Brain Mitochondria in a Toxic Model Induced by 3-Nitropropionic Acid: an In Vitro Study.

Mitochondrial dysfunction plays a key role in the development of neurodegenerative disorders. In contrast, the regulation of the endocannabinoid system has been shown to promote neuroprotection in different neurotoxic paradigms. The existence of an active form of the cannabinoid receptor 1 (CB1R) in mitochondrial membranes (mitCB1R), which might exert its effects through the same signaling mechanisms as the cell membrane CB1R, has been shown to regulate mitochondrial activity. Although there is evidence suggesting that some cannabinoids may induce protective effects on isolated mitochondria, substantial evidence on the role of cannabinoids in mitochondria remains to be explored. In this work, we developed a toxic model of mitochondrial dysfunction induced by exposure of brain mitochondria to the succinate dehydrogenase inhibitor 3-nitropropionic acid (3-NP). Mitochondria were also pre-incubated with the endogenous agonist anandamide (AEA) and the synthetic CB1R agonist WIN 55212-2 to evaluate their protective effects. Mitochondrial reduction capacity, reactive oxygen species (ROS) formation, and mitochondrial swelling were assessed as toxic markers. While 3-NP decreased the mitochondrial reduction capacity and augmented mitochondrial ROS formation and swelling, both AEA and WIN 55212-2 ameliorated these toxic effects. To explore the possible involvement of mitCB1R activation on the protective effects of AEA and WIN 55212-2, mitochondria were also pre-incubated in the presence of the selective CB1R antagonist AM281, which completely reverted the protective effects of the cannabinoids to levels similar to those evoked by 3-NP. These results show partial protective effects of cannabinoids, suggesting that mitCB1R activation may be involved in the recovery of compromised mitochondrial activity, related to reduction of ROS formation and further prevention of mitochondrial swelling.

Quercetin and dasatinib, two powerful senolytics in age-related cardiovascular disease.

Cellular senescence is characteristic of the development and progression of multiple age-associated diseases. Accumulation of senescent cells in the heart contributes to various age-related pathologies. Several compounds called senolytics have been designed to eliminate these cells within the tissues. In recent years, the use and study of senolytics increased, representing a promising field for finding accessible and safe therapies for cardiovascular disease (CVD) treatment. This mini-review discusses the changes in the aging heart and the participation of senescent cells in CVD, as well as the use of senolytics to prevent the progression of myocardial damage, mainly the effect of dasatinib and quercetin. In particular, the mechanisms and physiological effects of senolytics therapies in the aged heart are discussed.

NAC Pre-Administration Prevents Cardiac Mitochondrial Bioenergetics, Dynamics, Biogenesis, and Redox Alteration in Folic Acid-AKI-Induced Cardio-Renal Syndrome Type 3.

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.

Sulforaphane modifies mitochondrial-endoplasmic reticulum associations through reductive stress in cardiomyocytes.

Mitochondria-endoplasmic reticulum (ER) communication relies on platforms formed at the ER membrane with the mitochondrial outer membrane contact sites (MERCs). MERCs are involved in several processes including the unfolded protein response (UPR) and calcium (Ca2+) signaling. Therefore, as alterations in MERCs greatly impact cellular metabolism, pharmacological interventions to preserve productive mitochondrial-ER communication have been explored to maintain cellular homeostasis. In this regard, extensive information has documented the beneficial and potential effects of sulforaphane (SFN) in different pathological conditions; however, controversy has arisen regarding the effect of this compound on mitochondria-ER interaction. Therefore, in this study, we investigated whether SFN could induce changes in MERCs under normal culture conditions without damaging stimuli. Our results indicate that non-cytotoxic concentration of 2.5 µM SFN increased ER stress in cardiomyocytes in conjunction with a reductive stress environment, that diminishes ER-mitochondria association. Additionally, reductive stress promotes Ca2+ accumulation in the ER of cardiomyocytes. These data show an unexpected effect of SFN on cardiomyocytes grown under standard culture conditions, promoted by the cellular redox unbalance. Therefore, it is necessary to rationalize the use of compounds with antioxidant properties to avoid triggering cellular side effects.

Cardiosome-mediated protection in myocardial ischemia.

Cardiosomes, exosomes released in cardiospheres by cardiomyocytes and progenitor cells, communicate locally and at a distance from different tissues, promoting beneficial cellular changes. For example, miRNAs have emerged as regulators of intercellular communication via transport by extracellular vesicles in general and cardiosomes specifically. Although cardiosomes are considered biomarkers owing to their immense biomedical application in various clinical fields, their role in cardiovascular diseases remains unclear. This mini-review examines the experimental and clinical evidence for cardiosomes as non-invasive diagnostic, treatment and prognostic tools in acute myocardial infarction, the novelty of which is often lost in medical practice. In addition, we discuss the potential role of cardiosomes in physiologic mechanisms and cell signaling in cardiac conditioning strategies against reperfusion injury.

Osthole Prevents Heart Damage Induced by Diet-Induced Metabolic Syndrome: Role of Fructokinase (KHK).

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.

MicroRNA Dysregulation in Early Breast Cancer Diagnosis: A Systematic Review and Meta-Analysis.

Breast cancer continues to be the leading cause of death in women worldwide. Mammography, which is the current gold standard technique used to diagnose it, presents strong limitations in early ages where breast cancer is much more aggressive and fatal. MiRNAs present in numerous body fluids might represent a new line of research in breast cancer biomarkers, especially oncomiRNAs, known to play an important role in the suppression and development of neoplasms. The aim of this systematic review and meta-analysis was to evaluate dysregulated miRNA biomarkers and their diagnostic accuracy in breast cancer. Two independent researchers reviewed the included studies according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. A protocol for this review was registered in PROSPERO with the registration number "CRD42021256338". Observational case-control-based studies analyzing concentrations of microRNAs which have been published within the last 10 years were selected, and the concentrations of miRNAs in women with breast cancer and healthy controls were analyzed. Random-effects meta-analyses of miR-155 were performed on the studies which provided enough data to calculate diagnostic odds ratios. We determined that 34 microRNAs were substantially dysregulated and could be considered biomarkers of breast cancer. Individually, miR-155 provided better diagnostic results than mammography on average. However, when several miRNAs are used to screen, forming a panel, sensitivity and specificity rates improve, and they can be associated with classic biomarkers such us CA-125 or CEA. Based on the results of our meta-analysis, miR-155 might be a promising diagnostic biomarker for this patient population.

Anomalous aortic origin of the left coronary artery / Origen aórtico anómalo de la arteria coronaria izquierda

Abstract We present an unusual case of an anomalous left coronary artery arising from the contralateral sinus of Valsalva: a 63-year-old male patient who consulted to our emergency department with 1-week history of progressive dyspnea on exertion with clinical signs of heart failure, associated with lung congestion on the chest X ray and elevated NT-proBNP levels (2000 pg/ml; normal value <150). Doppler echocardiography showed severe dilation of both left atrium and left ventricle, with severe deterioration of LV systolic function (Ejection fraction of 26%), global hypokinesia and a moderate mitral regurgitation with central jet. A cardiac cath eterization was performed, which evidenced an anomalous origin of the left main coronary artery from the right coronary sinus with a proximal lesion of nearly 50%. A coronary computed tomographic angiography confirmed the diagnosis of an anomalous origin with an intramyocardial path at the level of the interventricular septum, as sociated with moderate extrinsic compression. To determine the degree of functional ischemia presented by the left main coronary artery lesion we performed a fractional flow reserve evaluation, resulting in 0.75, which was ranked as significant. An angioplasty with implantation of a drug-eluting stent (with Everolimus) was performed successfully to the target lesion. The patient evolved favorably during hospitalization and was discharged from the medical center to continue outpatient follow-up. Patient remained asymptomatic at 1-month and 6 months, during clinical evaluation, without evidence of ischemia on noninvasive functional assessment.

Resumen Presentamos un raro caso de nacimiento anómalo de arteria coronaria izquierda en el seno de Valsalva contralateral. Se trata de un hombre de 63 años que consultó al servicio de emergencias de nuestro centro por disnea progresiva de una semana de evolución, con signos clínicos de insuficiencia cardíaca, aso ciado a signos de congestión en la radiografía de tórax, y valores de NT-proBNP elevados (2000 pg/ml; valor normal <150). El ecocardiograma Doppler evidenció dilatación grave de la aurícula y del ventrículo izquierdo, con deterioro grave de la función sistólica (fracción de eyección de 26%), hipoquinesia global e insuficiencia mitral moderada con jet central. Se realizó una cinecoronariografía que evidenció el nacimiento anómalo del tronco de arteria coronaria izquierda desde el seno coronario derecho, con una lesión cercana al 50%. Una angiotomografía coronaria confirmó el origen anómalo del vaso coronario, con trayecto intramiocárdico a nivel del septum interventricular asociado a compresión extrínseca moderada. Para determinar el grado de isquemia funcional que presentaba la lesión del tronco coronario izquierdo se evaluó la reserva de flujo fraccional, que arrojó un resultado de 0.75 el cual se consideró significativo, prosiguiendo a angioplastia con implante de stent liberador de droga (con Everolimus) a dicha lesión. El paciente evolucionó favorablemente durante la internación en el hospital, egresando de la institución para continuar seguimiento ambulatorio. Persistió asintomático en los controles realizados al mes y a los 6 meses, sin evidencia de isquemia en la evaluación funcional no invasiva.

Actin-Cytoskeleton Drives Caveolae Signaling to Mitochondria during Postconditioning.

Caveolae-associated signaling toward mitochondria contributes to the cardioprotective mechanisms against ischemia-reperfusion (I/R) injury induced by ischemic postconditioning. In this work, we evaluated the role that the actin-cytoskeleton network exerts on caveolae-mitochondria communication during postconditioning. Isolated rat hearts subjected to I/R and to postconditioning were treated with latrunculin A, a cytoskeleton disruptor. Cardiac function was compared between these hearts and those exposed only to I/R and to the cardioprotective maneuver. Caveolae and mitochondria structures were determined by electron microscopy and maintenance of the actin-cytoskeleton was evaluated by phalloidin staining. Caveolin-3 and other putative caveolae-conforming proteins were detected by immunoblot analysis. Co-expression of caveolin-3 and actin was evaluated both in lipid raft fractions and in heart tissue from the different groups. Mitochondrial function was assessed by respirometry and correlated with cholesterol levels. Treatment with latrunculin A abolishes the cardioprotective postconditioning effect, inducing morphological and structural changes in cardiac tissue, reducing F-actin staining and diminishing caveolae formation. Latrunculin A administration to post-conditioned hearts decreases the interaction between caveolae-forming proteins, the co-localization of caveolin with actin and inhibits oxygen consumption rates in both subsarcolemmal and interfibrillar mitochondria. We conclude that actin-cytoskeleton drives caveolae signaling to mitochondria during postconditioning, supporting their functional integrity and contributing to cardiac adaption against reperfusion injury.

Anomalous aortic origin of the left coronary artery.

We present an unusual case of an anomalous left coronary artery arising from the contralateral sinus of Valsalva: a 63-year-old male patient who consulted to our emergency department with 1-week history of progressive dyspnea on exertion with clinical signs of heart failure, associated with lung congestion on the chest X ray and elevated NT-proBNP levels (2000 pg/ml; normal value <150). Doppler echocardiography showed severe dilation of both left atrium and left ventricle, with severe deterioration of LV systolic function (Ejection fraction of 26%), global hypokinesia and a moderate mitral regurgitation with central jet. A cardiac catheterization was performed, which evidenced an anomalous origin of the left main coronary artery from the right coronary sinus with a proximal lesion of nearly 50%. A coronary computed tomographic angiography confirmed the diagnosis of an anomalous origin with an intramyocardial path at the level of the interventricular septum, associated with moderate extrinsic compression. To determine the degree of functional ischemia presented by the left main coronary artery lesion we performed a fractional flow reserve evaluation, resulting in 0.75, which was ranked as significant. An angioplasty with implantation of a drug-eluting stent (with Everolimus) was performed successfully to the target lesion. The patient evolved favorably during hospitalization and was discharged from the medical center to continue outpatient follow-up. Patient remained asymptomatic at 1-month and 6 months, during clinical evaluation, without evidence of ischemia on noninvasive functional assessment.

Presentamos un raro caso de nacimiento anómalo de arteria coronaria izquierda en el seno de Valsalva contralateral. Se trata de un hombre de 63 años que consultó al servicio de emergencias de nuestro centro por disnea progresiva de una semana de evolución, con signos clínicos de insuficiencia cardíaca, asociado a signos de congestión en la radiografía de tórax, y valores de NT-proBNP elevados (2000 pg/ml; valor normal <150). El ecocardiograma Doppler evidenció dilatación grave de la aurícula y del ventrículo izquierdo, con deterioro grave de la función sistólica (fracción de eyección de 26%), hipoquinesia global e insuficiencia mitral moderada con jet central. Se realizó una cinecoronariografía que evidenció el nacimiento anómalo del tronco de arteria coronaria izquierda desde el seno coronario derecho, con una lesión cercana al 50%. Una angiotomografía coronaria confirmó el origen anómalo del vaso coronario, con trayecto intramiocárdico a nivel del septum interventricular asociado a compresión extrínseca moderada. Para determinar el grado de isquemia funcional que presentaba la lesión del tronco coronario izquierdo se evaluó la reserva de flujo fraccional, que arrojó un resultado de 0.75 el cual se consideró significativo, prosiguiendo a angioplastia con implante de stent liberador de droga (con Everolimus) a dicha lesión. El paciente evolucionó favorablemente durante la internación en el hospital, egresando de la institución para continuar seguimiento ambulatorio. Persistió asintomático en los controles realizados al mes y a los 6 meses, sin evidencia de isquemia en la evaluación funcional no invasiva.

A Phase 2, Randomized, Multicenter, Placebo-Controlled, Proof-of-Concept Trial of Oral Fexinidazole in Adults With Chronic Indeterminate Chagas Disease.

BACKGROUND: Chagas disease (CD) has significant global health impact, but safe, effective treatments remain elusive. The nitroimidazole fexinidazole is a potential treatment. METHODS: This double-blind, randomized, placebo-controlled, dose-finding, proof-of-concept study was conducted in Bolivia. Adults with serologically confirmed chronic indeterminate CD and positive PCR were randomly assigned to 1 of 6 fexinidazole regimens (1200 or 1800 mg/day for 2, 4, or 8 weeks) or placebo. Target recruitment was 20 patients/arm. The primary endpoint was sustained parasitological clearance by serial negative qPCR from end of treatment (EOT) until 6 months follow-up in the intention-to-treat (ITT) population. Follow-up was extended to 12 months. RESULTS: Enrollment was interrupted after 4/47 patients presented with transient asymptomatic grade 3 and 4 neutropenia. Treatment of ongoing patients was stopped in all patients administered >2 weeks. A total of 40 patients received treatment with fexinidazole from 3 days to 8 weeks. Delayed-onset neutropenia (n = 8) and increased liver enzymes (n = 8) were found in fexinidazole patients vs none in the placebo arm. In the ITT analysis, sustained parasitological clearance from EOT to 12 months follow-up varied between 66.7% (1200 mg-2 week) and 100.0% (1800 mg-2 week). Rapid, sustained clearance of parasitemia was observed in all treated patients with available data, but not in any patients in the placebo group, at 12 months (P = .0056). Further exploratory exposure-response analysis suggested low dosages of fexinidazole may be safe and effective. CONCLUSIONS: Further evaluation is needed to establish fexinidazole's minimum effective dosage and risk-benefit relationship. Results suggest potential for effective treatment regimens <10 days. CLINICAL TRIALS REGISTRATION: NCT02498782.

Mechanical power measurement during mechanical ventilation of SARS-CoV-2 critically ill patients. A cohort study / Medición del poder mecánico durante ventilación mecánica en pacientes críticamente enfermos con SARS-CoV-2, Estudio de cohorte

Abstract Introduction: The ventilator-induced lung injury (VILI) depends on the amount of energy per minute transferred by the ventilator to the lung measured in Joules, which is called mechanical power. Mechanical power is a development variable probably associated with outcomes in ventilated patients. Objective: To describe the value of mechanical power in patients with SARS-CoV-2 infection and ventilated for other causes and its relationship between days of mechanical ventilation, length of stay in the intensive care unit (ICU), and mortality. Methods: A multicenter, analytical, observational cohort study was conducted in patients with SARS-CoV-2 infection who required invasive mechanical ventilation and patients ventilated for other causes for more than 24 hours. Results: The cohort included 91 patients on mechanical ventilation in three tertiary care centers in the city of Pereira, Colombia. The average value of the mechanical power found was 22.7 ± 1 Joules/ min. In the subgroup of patients with SARS-CoV-2 infection, the value of mechanical power was higher 26.8 ± 9 than in the subgroup of patients without a diagnosis of SARS-CoV-2 infection 18.2 ± 1 (p <0.001). Conclusions: Mechanical power is an important variable to consider during the monitoring of mechanical ventilation. This study found an average value of mechanical power of 22.7 ± 1 Joules/min, being higher in patients with SARS-CoV-2 infection related to longer days of mechanical ventilation and a longer stay in the ICU.

Resumen Introducción: La lesión pulmonar inducida por la ventilación mecánica (LPIVM) depende, entre otras variables, de la cantidad de energía -medida en Joules- por unidad de tiempo transferida desde el ventilador al paciente, también llamada poder mecánico. El poder mecánico es una variable de desarrollo, posiblemente asociada a los desenlaces en pacientes sometidos a ventilación. Objetivo: Describir el valor del poder mecánico en pacientes con infección por SARS-CoV-2 y ventilados por otras causas y la relación entre días de ventilación mecánica, estancia en la UCI y mortalidad. Métodos: Estudio multicéntrico, analítico y observacional de cohorte realizado en pacientes con diagnóstico de infección por SARS-CoV-2 que requirieron soporte ventilatorio mecánico invasivo y pacientes ventilados por otras causas, durante más de 24 horas. Resultados: La cohorte incluyó 91 pacientes que recibieron ventilación mecánica en 3 centros de tercer nivel de la ciudad de Pereira, Colombia. El valor promedio del poder mecánico obtenido fue 22,7 ± 1 Joules/min. En el grupo de pacientes con infección por SARS-CoV-2 el valor obtenido fue mayor (26,8 ± 9), comparado con el grupo de pacientes sin infección por SARS-CoV-2 (18,2 ± 1) (p <0,001). Conclusiones: El poder mecánico es una variable importante a tener en cuenta en el monitoreo de la ventilación mecánica. El presente estudio encontró un valor promedio de poder mecánico de 22,7±1 Joules/min, siendo mayor en los pacientes con infección por SARS-CoV-2 en relación con más días de ventilación mecánica y estancia en UCI más prolongada.

Citicoline Modifies the Expression of Specific miRNAs Related to Cardioprotection in Patients with ST-Segment Elevation Myocardial Infarction Subjected to Coronary Angioplasty.

Extracellular vesicles are recognized as signaling mediators between cells both in physiological and pathological communication. In this work, we explored the potential effect of citicoline to modify relevant proteins or miRNAs for cardioprotection in the smallest population of such microvesicles; i.e., in exosomes from patients diagnosed with ST-segment elevation myocardial infarction (STEMI) undergoing coronary angioplasty. The plasma-exosome-enriched fraction from these patients was characterized. Their cellular origin was assessed by flow cytometry and Western blot, whereas miRNA expression was evaluated by real-time polymerase chain reaction (qRT-PCR). The content of caveolin-1, caveolin-3, and hnRNPA2B1, which play a relevant role in selective transport of miRNAs into microvesicles, along with the effect on cell viability of the exosomes obtained from citicoline-treated and untreated groups were also analyzed. Our results showed that hypoxic stress increases exosome release into the circulation. Moreover, we found that CD146+ increased in exosomes from citicoline-treated patients, while CD142+ decreased in these patients compared to the placebo group. No changes were detected in the protein levels of caveolin-1, caveolin-3, and hnRNPA2B1. Citicoline administration modified the expression of miR233-3p, miR92, and miR21-5p in exosomes. Cell viability decreased in the presence of exosomes from infarcted patients, while incubation of H9c2 cells with exosomes from patients reperfused with citicoline did not affect cell viability. In conclusion, citicoline administration modifies the expression of specific miRNAs related to cardioprotection in exosomes.

A ketogenic diet attenuates acute and chronic ischemic kidney injury and reduces markers of oxidative stress and inflammation.

BACKGROUND: Ischemic kidney injury is a common clinical condition resulting from transient interruption of the kidney's normal blood flow, leading to oxidative stress, inflammation, and kidney dysfunction. The ketogenic diet (KD), a low-carbohydrate, high-fat diet that stimulates endogenous ketone body production, has potent antioxidant and anti-inflammatory effects in distinct tissues and might thus protect the kidney against ischemia and reperfusion (IR) injury. MAIN METHODS: Male Wistar rats were fed a KD or a control diet (CD) for three days before analyzing metabolic parameters or testing nephroprotection. We used two different models of kidney IR injury and conducted biochemical, histological, and Western blot analyses at 24 h and two weeks after surgery. KEY FINDINGS: Acute KD feeding caused protein acetylation, liver AMPK activation, and increased resistance to IR-induced kidney injury. At 24 h after IR, rats on KD presented reduced tubular damage and improved kidney functioning compared to rats fed with a CD. KD attenuated oxidative damage (protein nitration, 4-HNE adducts, and 8-OHdG), increased antioxidant defenses (GPx and SOD activity), and reduced inflammatory intermediates (IL6, TNFα, MCP1), p50 NF-κB expression, and cellular infiltration. Also, KD prevented interstitial fibrosis development at two weeks, up-regulation of HSP70, and chronic Klotho deficiency. SIGNIFICANCE: Our findings demonstrate for the first time that short-term KD increases tolerance to experimental kidney ischemia, opening the opportunity for future therapeutic exploration of a dietary preconditioning strategy to convey kidney protection in the clinic.

Senescence in Primary Rat Astrocytes Induces Loss of the Mitochondrial Membrane Potential and Alters Mitochondrial Dynamics in Cortical Neurons.

The decline in brain function during aging is one of the most critical health problems nowadays. Although senescent astrocytes have been found in old-age brains and neurodegenerative diseases, their impact on the function of other cerebral cell types is unknown. The aim of this study was to evaluate the effect of senescent astrocytes on the mitochondrial function of a neuron. In order to evaluate neuronal susceptibility to a long and constant senescence-associated secretory phenotype (SASP) exposure, we developed a model by using cellular cocultures in transwell plates. Rat primary cortical astrocytes were seeded in transwell inserts and induced to premature senescence with hydrogen peroxide [stress-induced premature senescence (SIPS)]. Independently, primary rat cortical neurons were seeded at the bottom of transwells. After neuronal 6 days in vitro (DIV), the inserts with SIPS-astrocytes were placed in the chamber and cocultured with neurons for 6 more days. The neuronal viability, the redox state [reduced glutathione/oxidized glutathione (GSH/GSSG)], the mitochondrial morphology, and the proteins and membrane potential were determined. Our results showed that the neuronal mitochondria functionality was altered after being cocultured with senescent astrocytes. In vivo, we found that old animals had diminished mitochondrial oxidative phosphorylation (OXPHOS) proteins, redox state, and senescence markers as compared to young rats, suggesting effects of the senescent astrocytes similar to the ones we observed in vitro. Overall, these results indicate that the microenvironment generated by senescent astrocytes can affect neuronal mitochondria and physiology.