Association Between Hyperlactatemia, Perfusional Parameters, and Lymphocyte Mitochondrial Dysfunction in Septic Shock Patients.

INTRODUCTION: In septic shock, mitochondrial dysfunction, and hypoperfusion are the main triggers of multi-organ failure. Little is known about the crosstalk between mitochondrial dysfunction and hemodynamic alterations, especially in the post-resuscitation phase. Here, we assess whether hypoperfusion and lactate levels are associated with oxygen consumption linked to mitochondrial bioenergetic activity in lymphocytes of patients admitted with septic shock. PATIENTS AND METHODS: Prospective cohort study in patients with septic shock defined as the requirement of vasopressors to maintain a mean arterial pressure 65 mm Hg after initial fluid administration. Basal mitochondrial and Complex I respiration was measured to evaluate mitochondrial activity. Both variables and capillary refill time were compared with arterial lactate post-fluid resuscitation. We also compared mitochondrial activity measurements between patients with and without hypoperfusion status. RESULTS: A total of 90 patients were included in analysis. The median arterial lactate at the time of septic shock diagnosis was 2.0 mmol/Dl (IQR 1.3-3.0). Baseline respiration at the time of septic shock diagnosis was correlated with lactate (Spearman -0.388, 95% CI -0.4893 to -0.1021; P = 0.003), as well as Complex I respiration (Spearman -0.403, 95% CI -0.567 to -0.208; P < 0.001). Patients with hypoperfusion status had no difference in basal respiration when compared with patients who did not have hypoperfusion status (P = 0.22) nor in Complex I respiration (P = 0.09). CONCLUSION: Changes in lymphocytic mitochondrial metabolism are associated with post-resuscitation arterial lactate in septic shock; however, they are not associated with the presence of a hypoperfusional status. In this scenario, it is therefore suggested that systemic perfusion and mitochondrial metabolism have different courses.

Plasma Cellular Hypoxia, Mitochondrial Dysfunction, Disease Risk and Prognostic Factors in Type 2 Diabetic Patients in Saudi Arabia / Hipoxia celular plasmática, disfunción mitocondrial, riesgo de enfermedad y factores pronósticos en pacientes diabéticos tipo 2 en Arabia Saudita

ABSTRACT Objective: This cross-sectional study evaluated the association of plasma cytochrome c (CytoC) and hypoxia-inducible factor (HIF)-1α, as mitochondrial dysfunction and cellular hypoxia biomarkers, with disease risk factors and prognosis in Type 2 diabetic patients in Saudi Arabia. Methods: A total of 252 patients (94 males and 158 females) were eligible and were matched by socio-economic status, age and body mass index (BMI) with 106 healthy participants (71 males and 35 females). They were subgrouped according to BMI, disease duration and treatment. Lipid and glycaemic control indices were colorimetrically measured to calculate insulin resistance (IR) and atherogenic index of plasma (AIP). Haemoglobin A1c, C-reactive protein (CRP), CytoC and HIF-1α were measured using specific immunoassays. Results: Among the patients, 50% (38.64% of males and 52.53% of females), 40.48% (43.18% of males and 40.51% of females), 4.365% (6.82% of males and 3.80% of females), 2.381% (4.55% of males and 1.90% of females), and ~0.8% (males) suffered from peripheral neuropathy, ophthalmopathy, kidney disease, myocardial infarction and ketoacidosis, respectively. The majority of complicated cases had greater age, BMI, disease duration, plasma insulin and AIP, and were on insulin. The two investigated groups were non-significantly different considering CytoC, but highly significantly different considering lipid profile (as reflected on AIP) and glycaemic control parameters (as reflected on IR, plasma CRP and HIF-1α), with significant correlations among all of them in a group-specific pattern. Conclusion: Patients suffered a high rate of complications that correlated with age, BMI, disease duration, AIP, plasma insulin and insulin treatment due to poor disease control. Reduced HIF-1α and non-significant increased CytoC levels correlated negatively with bad prognostic indicators of the disease pointing to a pathogenetic implication.

RESUMEN Objetivo: Este estudio transversal evaluó la asociación del citocromo C del plasma (CitoC) y el factor inducible por hipoxia (HIF)-1α, como la disfunción mitocondrial y los biomarcadores de la hipoxia celular, con los factores de riesgo y pronóstico de enfermedad en pacientes diabéticos de tipo 2 en Arabia Saudita. Métodos: Un total de 252 pacientes (94 varones y 158 mujeres) fueron elegidos y apareados por estado socioeconómico, edad e índice de masa corporal (IMC) con 106 participantes sanos (71 varones y 35 hembras). Se dividieron entonces en subgrupos de acuerdo con el IMC, la duración de la enfermedad y el tratamiento. Se midieron los índices de lípidos y control glucémico para calcular la resistencia a la insulina (RI) y el índice aterogénico de plasma (IAP). la hemoglobina A1C, la proteína C-reactiva (PCR), CitoC y HIF-α fueron medidos usando inmunoensayos específicos. Resultados: Entre los pacientes, el 50% (38.64% de los varones y el 52.53% de las mujeres), 40.48% (43.18% de los varones y 40.51% de las mujeres), 4.365% (6.82% de los varones y 3.80% de las mujeres), 2.381% (4.55% de los varones y 1.90% de las mujeres), y ~ 0.8% (varones) padecían de neuropatía periférica, oftalmopatía, enfermedad renal, infarto de miocardio y cetoacidosis, respectivamente. la mayor parte de los casos complicados tenían mayor edad, IMC, duración de la enfermedad, insulina plasmática e IAP, y recibían tratamiento de insulina. Los dos grupos investigados no fueron significativamente diferentes considerando la CitoC, pero fueron muy significativamente diferentes en cuanto a su perfil lipídico (como se refleja en el IAP) y los parámetros de control glicémico (como se refleja en la RI, el plasma y el HIF-α), con importantes correlaciones entre todos ellos en un patrón específico de grupo. Conclusión: Los pacientes tuvieron un alto índice de complicaciones que se correlacionaron con la edad, el IMC, la duración de la enfermedad, el IAP, la insulina plasmática y el tratamiento de la insulina debido al pobre control de la enfermedad. La reducción del HIF-α y el aumento no significativo de los niveles de CitoC se correlacionaron negativamente con los indicadores de mal pronóstico de la enfermedad, que apuntaban a una implicación patogénica.

A Selection of Important Genes and Their Correlated Behavior in Alzheimer's Disease.

In 2017, approximately 5 million Americans were living with Alzheimer's disease (AD), and it is estimated that by 2050 this number could increase to 16 million. In this study, we apply mathematical optimization to approach microarray analysis to detect differentially expressed genes and determine the most correlated structure among their expression changes. The analysis of GSE4757 microarray dataset, which compares expression between AD neurons without neurofibrillary tangles (controls) and with neurofibrillary tangles (cases), was casted as a multiple criteria optimization (MCO) problem. Through the analysis it was possible to determine a series of Pareto efficient frontiers to find the most differentially expressed genes, which are here proposed as potential AD biomarkers. The Traveling Sales Problem (TSP) model was used to find the cyclical path of maximal correlation between the expression changes among the genes deemed important from the previous stage. This leads to a structure capable of guiding biological exploration with enhanced precision and repeatability. Ten genes were selected (FTL, GFAP, HNRNPA3, COX1, ND2, ND3, ND4, NUCKS1, RPL41, and RPS10) and their most correlated cyclic structure was found in our analyses. The biological functions of their products were found to be linked to inflammation and neurodegenerative diseases and some of them had not been reported for AD before. The TSP path connects genes coding for mitochondrial electron transfer proteins. Some of these proteins are closely related to other electron transport proteins already reported as important for AD.

[Molecular Mechanisms of Insulin Resistance: An Update]. / Mecanismos Moleculares de la Resistencia a la Insulina: Una Actualización.

The biological actions of insulin are initiated by activating its membrane receptor, which triggers multiple signaling pathways to mediate their biological actions. Due to the importance of metabolic regulation and promoting functions of cell growth and proliferation, insulin actions are highly regulated to promote proper metabolic functioning and energy balance. If these mechanisms are altered, this can lead to a condition known as insulin resistance, which is the consequence of a deficient insulin signaling caused by mutations or post-translational modifications of the receptor or effector molecules located downstream. Insulin resistance is one of the main characteristics of pathological manifestations associated with type 2 diabetes mellitus, one of the leading causes of death in Mexico and worldwide. In recent years, it has been found that conditions such as inflammation, endoplasmic reticulum stress, and mitochondrial dysfunction promote insulin resistance. The aim of this review is to elucidate the molecular aspects of insulin resistance and the mechanisms involved in regulating its effects, with particular emphasis on the role of inflammation, endoplasmic reticulum stress, and mitochondrial dysfunction.

Oxidative stress and mitochondrial dysfunction-linked neurodegenerative disorders.

Reactive species play an important role in physiological functions. Overproduction of reactive species, notably reactive oxygen (ROS) and nitrogen (RNS) species along with the failure of balance by the body's antioxidant enzyme systems results in destruction of cellular structures, lipids, proteins, and genetic materials such as DNA and RNA. Moreover, the effects of reactive species on mitochondria and their metabolic processes eventually cause a rise in ROS/RNS levels, leading to oxidation of mitochondrial proteins, lipids, and DNA. Oxidative stress has been considered to be linked to the etiology of many diseases, including neurodegenerative diseases (NDDs) such as Alzheimer diseases, Amyotrophic lateral sclerosis, Friedreich's ataxia, Huntington's disease, Multiple sclerosis, and Parkinson's diseases. In addition, oxidative stress causing protein misfold may turn to other NDDs include Creutzfeldt-Jakob disease, Bovine Spongiform Encephalopathy, Kuru, Gerstmann-Straussler-Scheinker syndrome, and Fatal Familial Insomnia. An overview of the oxidative stress and mitochondrial dysfunction-linked NDDs has been summarized in this review.

Regulation of Mitochondrial Function and Glutamatergic System Are the Target of Guanosine Effect in Traumatic Brain Injury.

Traumatic brain injury (TBI) is a highly complex multi-factorial disorder. Experimental trauma involves primary and secondary injury cascades that underlie delayed neuronal dysfunction and death. Mitochondrial dysfunction and glutamatergic excitotoxicity are the hallmark mechanisms of damage. Accordingly, a successful pharmacological intervention requires a multi-faceted approach. Guanosine (GUO) is known for its neuromodulator effects in various models of brain pathology, specifically those that involve the glutamatergic system. The aim of the study was to investigate the GUO effects against mitochondrial damage in hippocampus and cortex of rats subjected to TBI, as well as the relationship of this effect with the glutamatergic system. Adult male Wistar rats were subjected to a unilateral moderate fluid percussion brain injury (FPI) and treated 15 min later with GUO (7.5 mg/kg) or vehicle (saline 0.9%). Analyses were performed in hippocampus and cortex 3 h post-trauma and revealed significant mitochondrial dysfunction, characterized by a disrupted membrane potential, unbalanced redox system, decreased mitochondrial viability, and complex I inhibition. Further, disruption of Ca2+ homeostasis and increased mitochondrial swelling was also noted. Our results showed that mitochondrial dysfunction contributed to decreased glutamate uptake and levels of glial glutamate transporters (glutamate transporter 1 and glutamate aspartate transporter), which leads to excitotoxicity. GUO treatment ameliorated mitochondrial damage and glutamatergic dyshomeostasis. Thus, GUO might provide a new efficacious strategy for the treatment acute physiological alterations secondary to TBI.

Actualización sobre el tema de enfermedades mitocondriales / Updating on the Topic of Mitochondrial Diseases

Las enfermedades mitocondriales son un grupo de patologías multisistémicas heterogéneas en las cuales la presentación clínica; genética, bioquímica, e histopatológica muestran una disfunción mitocondrial. Las alteraciones pueden depender del ADN mitocondrial, de alteraciones del ADN nuclear o de alteraciones en la comunicación de los genomas mitocondriales y nucleares. Su diagnóstico requiere del reconocimiento previo de la presentación clínica y se apoya fundamentalmente en la biopsia de músculo y los estudios moleculares para buscar las mutaciones en el ADN mitocondrial. Las enfermedades mitocondriales constituyen un reto para los médicos. Las mitocondrias poseen su propio ADN y al producirse un daño de este, se originan las enfermedades mitocondriales, relacionadas con la génesis del Alzheimer, el Parkinson y la diabetes mellitus. Un conocimiento actualizado sobre estas afecciones posibilita un mejor diagnóstico y manejo de estos pacientes, por ello se realizó una revisión del estado actual del tema en la literatura mundial.(AU)

Mitochondrial diseases are a group of heterogeneous multisystem diseases in which the clinical presentation; genetic, biochemical, and histopathological show mitochondrial dysfunction. The disorders may depend on the proper mitochondrial DNA, nuclear DNA disorders or changes in communication mitochondrial and nuclear genomes. Its diagnosis requires the prior recognition of the clinical presentation and relies primarily on muscle biopsy and molecular studies to look for mutations in mitochondrial DNA. Mitochondrial diseases are a challenge for physicians. Mitochondria have their own DNA and damage this occurs, mitochondrial diseases related to the genesis of Alzheimer's, Parkinson's and diabetes mellitus. An updated knowledge of these diseases allows better diagnosis and management of these patients that is why a literature review of the current status of the topic was performed.(AU)

Hyperoxic preconditioning in partial liver ischemia.

PURPOSE: To evaluate the effect of the hyperbaric oxygen (HBO) treatment as a pre-conditioning for I/R effects in the liver ischemia. METHODS: Fifty-seven male Wistar rats (260-300g) were submitted to the following procedures: SHAM; I/R, rats submitted to I/R, consisting of partial ischemia of 70% of the liver for 90 minutes followed by 15 minutes of reperfusion; HBO I/R 1 ATA, 30 minutes of HBO treatment at the pressure of 1 absolute atmosphere (ATA) during the ischemia time. HBO I/R 2 ATA, 30 minutes of HBO (2 ATA) during the ischemia time. Pre HBO I/R 30', rats submitted to 30 minutes of HBO (2 ATA) immediately before the I/R time. Pre HBO I/R 90', rats submitted to 90 minutes of HBO (2 ATA) immediately before the I/R time. RESULTS: There was a significant worsening of all the parameters of mitochondrial energy production (state 3, 4, RCR and Swelling) in the I/R group, when compared to the Sham group (I/R

Hyperoxic preconditioning in partial liver ischemia

PURPOSE: To evaluate the effect of the hyperbaric oxygen (HBO) treatment as a pre-conditioning for I/R effects in the liver ischemia. METHODS: Fifty-seven male Wistar rats (260-300g) were submitted to the following procedures: SHAM; I/R, rats submitted to I/R, consisting of partial ischemia of 70% of the liver for 90 minutes followed by 15 minutes of reperfusion; HBO I/R 1 ATA, 30 minutes of HBO treatment at the pressure of 1 absolute atmosphere (ATA) during the ischemia time. HBO I/R 2 ATA, 30 minutes of HBO (2 ATA) during the ischemia time. Pre HBO I/R 30', rats submitted to 30 minutes of HBO (2 ATA) immediately before the I/R time. Pre HBO I/R 90', rats submitted to 90 minutes of HBO (2 ATA) immediately before the I/R time. RESULTS: There was a significant worsening of all the parameters of mitochondrial energy production (state 3, 4, RCR and Swelling) in the I/R group, when compared to the Sham group (I/R <Sham, p<0.05). There was also a significant worsening in state 4, RCR and mitochondrial edema in the Pre HBO I/R 90' group compared to the I/R group. Hepatic enzyme concentrations were significantly higher in the I/R group. CONCLUSION: The use of hyperbaric oxygen before and during I/R did not improve the production of hepatocellular energy reduced by I/R, nor did it prevent the installation of mitochondrial edema induced by Iischemia/reperfusion. .

Mitochondrial dysfunction during sepsis.

Sepsis and multiple organ failure remain leading causes of death in intensive care patients. Recent advances in our understanding of the pathophysiology of these syndromes include a likely prominent role for mitochondria. Patient studies have shown that the degree of mitochondrial dysfunction is related to the eventual outcome. Associated mechanisms include damage to mitochondria or inhibition of the electron transport chain enzymes by nitric oxide and other reactive oxygen species (the effects of which are amplified by co-existing tissue hypoxia), hormonal influences that decrease mitochondrial activity, and downregulation of mitochondrial protein expression. Notably, despite these findings, there is minimal cell death seen in most affected organs, and these organs generally regain reasonably normal function should the patient survive. It is thus plausible that multiple organ failure following sepsis may actually represent an adaptive state whereby the organs temporarily 'shut down' their normal metabolic functions in order to protect themselves from an overwhelming and prolonged insult. A decrease in energy supply due to mitochondrial inhibition or injury may trigger this hibernation/estivation-like state. Likewise, organ recovery may depend on restoration of normal mitochondrial respiration. Data from animal studies show histological recovery of mitochondria after a septic insult that precedes clinical improvement. Stimulation of mitochondrial biogenesis could offer a new therapeutic approach for patients in multi-organ failure. This review will cover basic aspects of mitochondrial function, mechanisms of mitochondrial dysfunction in sepsis, and approaches to prevent, mitigate or speed recovery from mitochondrial injury.