Autophagic response to exercise in peripheral blood mononuclear cells from young men is intensity-dependent and is altered by exposure to environmental heat.

Autophagy is essential to maintaining cellular homeostasis in all eukaryotic cells and to tolerance of acute stressors such as starvation, heat, and recovery after exercise. Limited information exists regarding the exercise intensity-dependent autophagic response in humans, and it is unknown how environmental heat stress may modulate this response. Therefore, we evaluated autophagy and accompanying pathways of cellular stress [the heat-shock response (HSR), apoptosis, and acute inflammation] in peripheral blood mononuclear cells (PBMCs) from 10 young men (mean [SD]; 22 [2] years) before, immediately after and up to 6-h postexercise recovery from 30 min of low-, moderate-, and high-intensity semirecumbent cycling [40%, 55%, and 70% of maximal oxygen consumption (V̇o2max), respectively] in a temperate environment (25°C) and at 70% of V̇o2max in a hot environment (40°C). Changes in protein content were analyzed via Western blot. Each increase in exercise intensity was associated with elevations in mean body temperature. LC3-II increased after moderate-intensity exercise, with further increases after high-intensity exercise (P < 0.05). However, an increase in beclin-2 and ULK1, with a decrease in p62 was only observed after high-intensity exercise, which was paralleled by elevated TNF-α and cleaved-caspase-3, with the HSR peaking at 6 h after exercise (P < 0.05). When exercise was performed in the heat, greater LC3-II and cleaved-caspase-3 accumulation were observed; however, beclin-2 declined in recovery (P < 0.05). Therefore, our findings indicate that autophagy in PBMCs during exercise may be associated with greater heat strain exhibited during increasing exercise intensities, which is modulated by exposure to heat.

Temporal patterns of multi-morbidity in 570157 ischemic heart disease patients: a nationwide cohort study.

BACKGROUND: Patients diagnosed with ischemic heart disease (IHD) are becoming increasingly multi-morbid, and studies designed to analyze the full spectrum are few. METHODS: Disease trajectories, defined as time-ordered series of diagnoses, were used to study the temporality of multi-morbidity. The main data source was The Danish National Patient Register (NPR) comprising 7,179,538 individuals in the period 1994-2018. Patients with a diagnosis code for IHD were included. Relative risks were used to quantify the strength of the association between diagnostic co-occurrences comprised of two diagnoses that were overrepresented in the same patients. Multiple linear regression models were then fitted to test for temporal associations among the diagnostic co-occurrences, termed length two disease trajectories. Length two disease trajectories were then used as basis for constructing disease trajectories of three diagnoses. RESULTS: In a cohort of 570,157 IHD disease patients, we identified 1447 length two disease trajectories and 4729 significant length three disease trajectories. These included 459 distinct diagnoses. Disease trajectories were dominated by chronic diseases and not by common, acute diseases such as pneumonia. The temporal association of atrial fibrillation (AF) and IHD differed in different IHD subpopulations. We found an association between osteoarthritis (OA) and heart failure (HF) among patients diagnosed with OA, IHD, and then HF only. CONCLUSIONS: The sequence of diagnoses is important in characterization of multi-morbidity in IHD patients as the disease trajectories. The study provides evidence that the timing of AF in IHD marks distinct IHD subpopulations; and secondly that the association between osteoarthritis and heart failure is dependent on IHD.

Therapeutic benefits of proning to improve pulmonary gas exchange in severe respiratory failure: focus on fundamentals of physiology.

NEW FINDINGS: What is the topic of this review? The use of proning for improving pulmonary gas exchange in critically ill patients. What advances does it highlight? Proning places the lung in its 'natural' posture, and thus optimises the ventilation-perfusion distribution, which enables lung protective ventilation and the alleviation of potentially life-threatening hypoxaemia in COVID-19 and other types of critical illness with respiratory failure. ABSTRACT: The survival benefit of proning patients with acute respiratory distress syndrome (ARDS) is well established and has recently been found to improve pulmonary gas exchange in patients with COVID-19-associated ARDS (CARDS). This review outlines the physiological implications of transitioning from supine to prone on alveolar ventilation-perfusion ( V ̇ A -- Q ̇ ${\dot V_{\rm{A}}}\hbox{--}\dot Q$ ) relationships during spontaneous breathing and during general anaesthesia in the healthy state, as well as during invasive mechanical ventilation in patients with ARDS and CARDS. Spontaneously breathing, awake healthy individuals maintain a small vertical (ventral-to-dorsal) V ̇ A / Q ̇ ${\dot V_{\rm{A}}}/\dot Q$ ratio gradient in the supine position, which is largely neutralised in the prone position, mainly through redistribution of perfusion. In anaesthetised and mechanically ventilated healthy individuals, a vertical V ̇ A / Q ̇ ${\dot V_{\rm{A}}}/\dot Q$ ratio gradient is present in both postures, but with better V ̇ A -- Q ̇ ${\dot V_{\rm{A}}}\hbox{--}\dot Q$ matching in the prone position. In ARDS and CARDS, the vertical V ̇ A / Q ̇ ${\dot V_{\rm{A}}}/\dot Q$ ratio gradient in the supine position becomes larger, with intrapulmonary shunting in gravitationally dependent lung regions due to compression atelectasis of the dorsal lung. This is counteracted by proning, mainly through a more homogeneous distribution of ventilation combined with a largely unaffected high perfusion dorsally, and a consequent substantial improvement in arterial oxygenation. The data regarding proning as a therapy in patients with CARDS is still limited and whether the associated improvement in arterial oxygenation translates to a survival benefit remains unknown. Proning is nonetheless an attractive and lung protective manoeuvre with the potential benefit of improving life-threatening hypoxaemia in patients with ARDS and CARDS.

Reduced Hsp70 and Glutamine in Pediatric Severe Malaria Anemia: Role of Hemozoin in Suppressing Hsp70 and NF-κB activation.

Severe malarial anemia [SMA, hemoglobin (Hb) <5.0 g/dL] is a leading cause of global morbidity and mortality among children residing in Plasmodium falciparum transmission regions. Exploration of molecular pathways through global gene expression profiling revealed that SMA was characterized by decreased HSPA1A, a heat shock protein (Hsp) 70 coding gene. Hsp70 is a ubiquitous chaperone that regulates Nuclear Factor-kappa B (NF-κB) signaling and production of pro-inflammatory cytokines known to be important in malaria pathogenesis (e.g., IL-1ß, IL-6 and TNF-α). Since the role of host Hsp70 in malaria pathogenesis is unexplored, we investigated Hsp70 and molecular pathways in children with SMA. Validation experiments revealed that leukocytic HSP70 transcripts were reduced in SMA relative to non-severe malaria, and that intraleukocytic hemozoin (PfHz) was associated with lower HSP70. HSP70 was correlated with reticulocyte production and Hb. Since glutamine (Gln) up-regulates Hsp70, modulates NF-κB activation, and attenuates over-expression of pro-inflammatory cytokines, circulating Gln was measured in children with malaria. Reduced Gln was associated with increased risk of developing SMA. Treatment of cultured peripheral blood mononuclear cells (PBMCs) with PfHz caused a time-dependent decrease in Hsp70 transcripts/protein, and NF-κB activation. Gln treatment of PBMCs overcame PfHz-induced suppression of HSP70 transcripts/protein, reduced NF-κB activation, and suppressed over-expression of IL-1ß, IL-6 and TNF-α. Findings here demonstrate that SMA is characterized by reduced intraleukocytic HSP70 and circulating Gln, and that PfHz-induced suppression of HSP70 can be reversed by Gln. Thus, Gln supplementation may offer important immunotherapeutic options for futures studies in children with SMA.

The effect of insulin resistance and exercise on the percentage of CD16(+) monocyte subset in obese individuals.

UNLABELLED: Obesity is a low-grade chronic inflammation condition, and macrophages, and possibly monocytes, are involved in the pathological outcomes of obesity. Physical exercise is a low-cost strategy to prevent and treat obesity, probably because of its anti-inflammatory action. We evaluated the percentage of CD16(-) and CD16(+) monocyte subsets in obese insulin-resistant individuals and the effect of an exercise bout on the percentage of these cells. Twenty-seven volunteers were divided into three experimental groups: lean insulin sensitive, obese insulin sensitive and obese insulin resistant. Venous blood samples collected before and 1 h after an aerobic exercise session on a cycle ergometer were used for determination of monocyte subsets by flow cytometry. Insulin-resistant obese individuals have a higher percentage of CD16(+) monocytes (14.8 ± 2.4%) than the lean group (10.0 ± 1.3%). A positive correlation of the percentage of CD16(+) monocytes with body mass index and fasting plasma insulin levels was found. One bout of moderate exercise reduced the percentage of CD16(+) monocytes by 10% in all the groups evaluated. Also, the absolute monocyte count, as well as all other leukocyte populations, in lean and obese individuals, increased after exercise. This fact may partially account for the observed reduction in the percentage of CD16(+) cells in response to exercise. Insulin-resistant, but not insulin-sensitive obese individuals, have an increased percentage of CD16(+) monocytes that can be slightly modulated by a single bout of moderate aerobic exercise. These findings may be clinically relevant to the population studied, considering the involvement of CD16(+) monocytes in the pathophysiology of obesity. Copyright © 2016 John Wiley & Sons, Ltd. SIGNIFICANCE OF THE STUDY: Obesity is now considered to be an inflammatory condition associated with many pathological consequences, including insulin resistance. It is proposed that insulin resistance contributes to the aggravation of the inflammatory dysfunction in obesity. The effect of obesity on the percentage of monocytes was previously observed in class II and III obese individuals who presented other alterations in addition to insulin resistance. In this study we observed that insulin-resistant obese individuals, but not insulin-sensitive ones, had an increased percentage of CD14(+) CD16(+) monocytes. This fact shows that a dysfunction of the monocyte percentage in class I obese individuals is only seen when this condition is associated with insulin resistance.

Regulatory coordination between two major intracellular homeostatic systems: heat shock response and autophagy.

The eukaryotic cell depends on multitiered homeostatic systems ensuring maintenance of proteostasis, organellar integrity, function and turnover, and overall cellular viability. At the two opposite ends of the homeostatic system spectrum are heat shock response and autophagy. Here, we tested whether there are interactions between these homeostatic systems, one universally operational in all prokaryotic and eukaryotic cells, and the other one (autophagy) is limited to eukaryotes. We found that heat shock response regulates autophagy. The interaction between the two systems was demonstrated by testing the role of HSF-1, the central regulator of heat shock gene expression. Knockdown of HSF-1 increased the LC3 lipidation associated with formation of autophagosomal organelles, whereas depletion of HSF-1 potentiated both starvation- and rapamycin-induced autophagy. HSP70 expression but not expression of its ATPase mutant inhibited starvation or rapamycin-induced autophagy. We also show that exercise induces autophagy in humans. As predicted by our in vitro studies, glutamine supplementation as a conditioning stimulus prior to exercise significantly increased HSP70 protein expression and prevented the expected exercise induction of autophagy. Our data demonstrate for the first time that heat shock response, from the top of its regulatory cascade (HSF-1) down to the execution stages delivered by HSP70, controls autophagy thus connecting and coordinating the two extreme ends of the homeostatic systems in the eukaryotic cell.

Exercise regulation of intestinal tight junction proteins.

Gastrointestinal distress, such as diarrhoea, cramping, vomiting, nausea and gastric pain are common among athletes during training and competition. The mechanisms that cause these symptoms are not fully understood. The stress of heat and oxidative damage during exercise causes disruption to intestinal epithelial cell tight junction proteins resulting in increased permeability to luminal endotoxins. The endotoxin moves into the blood stream leading to a systemic immune response. Tight junction integrity is altered by the phosphoylation state of the proteins occludin and claudins, and may be regulated by the type of exercise performed. Prolonged exercise and high-intensity exercise lead to an increase in key phosphorylation enzymes that ultimately cause tight junction dysfunction, but the mechanisms are different. The purpose of this review is to (1) explain the function and physiology of tight junction regulation, (2) discuss the effects of prolonged and high-intensity exercise on tight junction permeability leading to gastrointestinal distress and (3) review agents that may increase or decrease tight junction integrity during exercise.

Thermotolerance and heat acclimation may share a common mechanism in humans.

Thermotolerance and heat acclimation are key adaptation processes that have been hitherto viewed as separate phenomena. Here, we provide evidence that these processes may share a common basis, as both may potentially be governed by the heat shock response. We evaluated the effects of a heat shock response-inhibitor (quercetin; 2,000 mg/day) on established markers of thermotolerance [gastrointestinal barrier permeability, plasma TNF-α, IL-6, and IL-10 concentrations, and leukocyte heat shock protein 70 (HSP70) content]. Heat acclimation reduced body temperatures, heart rate, and physiological strain during exercise/heat stress) in male subjects (n = 8) completing a 7-day heat acclimation protocol. These same subjects completed an identical protocol under placebo supplementation (placebo). Gastrointestinal barrier permeability and TNF-α were increased on the 1st day of exercise/heat stress in quercetin; no differences in these variables were reported in placebo. Exercise HSP70 responses were increased, and plasma cytokines (IL-6, IL-10) were decreased on the 7th day of heat acclimation in placebo; with concomitant reductions in exercise body temperatures, heart rate, and physiological strain. In contrast, gastrointestinal barrier permeability remained elevated, HSP70 was not increased, and IL-6, IL-10, and exercise body temperatures were not reduced on the 7th day of heat acclimation in quercetin. While exercise heart rate and physiological strain were reduced in quercetin, this occurred later in exercise than with placebo. Consistent with the concept that thermotolerance and heat acclimation are related through the heat shock response, repeated exercise/heat stress increases cytoprotective HSP70 and reduces circulating cytokines, contributing to reductions in cellular and systemic markers of heat strain. Exercising under a heat shock response-inhibitor prevents both cellular and systemic heat adaptations.

A review of sex differences in immune function after aerobic exercise.

When menstrual phase and oral contraceptives are controlled for, males and females display marked differences in immune response to an exercise stress. In highly controlled research studies, sex differences in immune cell changes, cytokine alterations, along with morbidity and mortality after inoculation are apparent. Exercise has been hypothesized to serve as a model of various clinical stresses by inducing similar hormonal and immunological alterations. Thus, a greater understanding of sex differences in post exercise non-specific immune function may provide insight into more effective clinical approaches and treatments. This paper reviews the recent evidence supporting sex differences in post exercise immune response and highlights the need for greater control when comparing the post exercise immune response between sexes.

Effects of whole-body heat acclimation on cell injury and cytokine responses in peripheral blood mononuclear cells.

To test the hypothesis that whole-body heat acclimation (HA) would increase peripheral blood mononuclear cells' (PBMC) tolerance to heat shock (HS) and/or alter the release of cytokines (IL-1ß, IL-6, IL-10 and TNF-α) to bacterial lipopolysaccharide (LPS), we heat acclimated nine subjects by exercising them for 100 min in a hot environment for 10 days. The subjects' PBMC were separated and cultured on days 1 and 10 of HA pre- and post-exercise. Pre-exercise PBMC were allocated to three treatments: control (PRE, 37°C), HS (42.5°C for 2 h), or LPS (1 ng mL(-1) for 24 h). Post-exercise samples were incubated at 37°C. PBMC lactate dehydrogenase release increased (p < 0.05) after HS but it was not different (p > 0.05) between days 1 and 10 (0.100 ± 0.012 and 0.102 ± 0.16 abs., respectively). LPS treatment induced an increased (p < 0.05) release of cytokines but HA did not alter this response (p > 0.05). Pre-exercise intracellular heat shock protein 72 (Hsp72) was higher (p < 0.05) on day 10 compared to day 1 of HA (13 ± 5 and 8 ± 5 ng mL(-1), respectively). HS treatment caused a greater increase (p < 0.05) in Hsp72 than the exercise sessions on HA days 1 and 10. In addition, after HA, the Hsp72 response to HS was reduced (day 1, 129 ± 46; day 10, 80 ± 32 ng mL(-1), p < 0.05). In conclusion, HA increases PBMC Hsp72 but it does not reduce cellular damage to HS or alter cytokine response to LPS. We speculate that the stress applied during HA is not sufficient to modify the PBMC response.

Autophagy and heat: a potential role for heat therapy to improve autophagic function in health and disease.

Autophagy is a crucial cell survival mechanism that involves the degradation and recycling of old or damaged organelles and proteins to maintain cellular homeostasis. Impairments in autophagy are central to the pathogenesis of many conditions including metabolic and neurodegenerative disorders, cardiovascular and pulmonary diseases, diabetes, and aging. Although various pharmacological agents may be able to stimulate autophagic function, to our knowledge, few interventions exist that have been deemed safe and effective in humans. An emerging body of evidence suggests that targeting the autophagic pathway via passive heating (heat therapy) may stimulate autophagic function. Therefore, the primary focus of the present review is to analyze the mechanisms in which passive heating induces autophagy as defined by in vitro and in vivo (animal and human) models. Our secondary focus is to examine the implications of utilizing passive heating to restore dysfunctional autophagy in chronic disease and aging. Finally, we discuss potential therapeutic strategies to implement passive heating to stimulate autophagic function in humans.

Optimizing drug selection from a prescription trajectory of one patient.

It is unknown how sequential drug patterns convey information on a patient's health status and treatment guidelines rarely account for this. Drug-agnostic longitudinal analyses of prescription trajectories in a population-wide setting are needed. In this cohort study, we used 24 years of data (1.1 billion prescriptions) from the Danish prescription registry to model the risk of sequentially redeeming a drug after another. Drug pairs were used to build multistep longitudinal prescription trajectories. These were subsequently used to stratify patients and calculate survival hazard ratios between the stratified groups. The similarity between prescription histories was used to determine individuals' best treatment option. Over the course of 122 million person-years of observation, we identified 9 million common prescription trajectories and demonstrated their predictive power using hypertension as a case. Among patients treated with agents acting on the renin-angiotensin system we identified four groups: patients prescribed angiotensin converting enzyme (ACE) inhibitor without change, angiotensin receptor blockers (ARBs) without change, ACE with posterior change to ARB, and ARB posteriorly changed to ACE. In an adjusted time-to-event analysis, individuals treated with ACE compared to those treated with ARB had lower survival probability (hazard ratio, 0.73 [95% CI, 0.64-0.82]; P < 1 × 10-16). Replication in UK Biobank data showed the same trends. Prescription trajectories can provide novel insights into how individuals' drug use change over time, identify suboptimal or futile prescriptions and suggest initial treatments different from first line therapies. Observations of this kind may also be important when updating treatment guidelines.

Activation of caspase-3 in the skeletal muscle during haemodialysis.

BACKGROUND AND OBJECTIVE: Muscle atrophy in end-stage renal disease (ESRD) may be due to the activation of apoptotic and proteolytic pathways. We hypothesized that activation of caspase-3 in the skeletal muscle mediates apoptosis and proteolysis during haemodialysis (HD). MATERIALS AND METHODS: Eight ESRD patients were studied before (pre-HD) and during HD and the findings were compared with those from six healthy volunteers. Protein kinetics was determined by primed constant infusion of L-(ring (13)C(6) ) Phenylalanine. RESULTS: Caspase-3 activity in the skeletal muscle was higher in ESRD patients pre-HD than in controls (24966·0 ± 4023·9 vs. 15293·3 ± 2120·0 units, P<0·01) and increased further during HD (end-HD) (37666·6 ± 4208·3 units) (P<0·001). Actin fragments (14 kDa) generated by caspase-3 mediated cleavage of actomyosin was higher in the skeletal muscle pre-HD (68%) and during HD (164%) compared with controls. The abundance of ubiquitinized carboxy-terminal actin fragment was also significantly increased during HD. Skeletal muscle biopsies obtained at the end of HD exhibited augmented apoptosis, which was higher than that observed in pre-HD and control samples (P<0·001). IL-6 content in the soluble fraction of the muscle skeletal muscle was increased significantly during HD. Protein kinetic studies showed that catabolism was higher in ESRD patients during HD compared with pre-HD and control subjects. Muscle protein catabolism was positively associated with caspase-3 activity and skeletal muscle IL-6 content. CONCLUSION: Muscle atrophy in ESRD may be due to IL-6 induced activation of caspase-3 resulting in apoptosis as well as muscle proteolysis during HD.

Sucrose co-administration reduces the toxic effect of lectin on gut permeability and intestinal bacterial colonization.

INTRODUCTION: Legume lectins can have toxic effects when consumed without adequate cooking, occasionally leading to an acute gastroenteritis. Lectins are sugar binging proteins and may use this property to execute their toxic effects; these toxic effects may be secondary to increased gut bacteria and intestinal permeability. However, whether or not sucrose rescues these toxic effects by decreasing gut bacterial concentration and intestinal permeability is unknown. AIM: Our aim was to test the hypothesis that sucrose may reduce toxic effects of legume lectins by protecting barrier function, bacterial overgrowth and bacterial translocation. METHODS: Twenty-four rats were randomized to an ad libitum diet of either standard rat chow, a chow containing 26% crude red kidney beans or a chow containing 26% crude red kidney beans supplemented with 1 mM sucrose in drinking water for 24 h. After 12-h fast, rats were gavaged with sugar probes; breath gas and urine were collected for 5 h. Intestine and liver tissues were then collected. Mucosa-associated total bacterial count were measured by targeting the 16s rRNA gene. Four groups of in vitro Caco-2 cell lines were treated with PBS, 200 µg/ml phytohemagglutinin (PHA), 1 mM sucrose and both 200 µg/ml PHA and 1 mM sucrose, respectively, and trans-epithelial resistance was measured. RESULTS: Rats fed crude red kidney beans for 24 h showed significant weight loss when compared to controls (P < 0.05), as well as increased intestinal permeability (P < 0.05), increased bacterial load (P < 0.05) and increased bacterial translocation to the liver (P < 0.05). Sucrose rescues the drop in trans-epithelial resistance due to PHA in CaCO2-cells (P < 0.05). CONCLUSIONS: Sucrose reduced crude red kidney beans induced increase in intestinal permeability, bacterial load and translocation. Since red kidney beans are an important source of dietary protein in the world, their potential toxicity when inadequately cooked may be rescued by a suitable complementary diet.

Association is not prediction: A landscape of confused reporting in diabetes - A systematic review.

AIMS: Appropriate analysis of big data is fundamental to precision medicine. While statistical analyses often uncover numerous associations, associations themselves do not convey predictive value. Confusion between association and prediction harms clinicians, scientists, and ultimately, the patients. We analyzed published papers in the field of diabetes that refer to "prediction" in their titles. We assessed whether these articles report metrics relevant to prediction. METHODS: A systematic search was undertaken using NCBI PubMed. Articles with the terms "diabetes" and "prediction" were selected. All abstracts of original research articles, within the field of diabetes epidemiology, were searched for metrics pertaining to predictive statistics. Simulated data was generated to visually convey the differences between association and prediction. RESULTS: The search-term yielded 2,182 results. After discarding non-relevant articles, 1,910 abstracts were evaluated. Of these, 39% (n = 745) reported metrics of predictive statistics, while 61% (n = 1,165) did not. The top reported metrics of prediction were ROC AUC, sensitivity and specificity. Using the simulated data, we demonstrated that biomarkers with large effect sizes and low P values can still offer poor discriminative utility. CONCLUSIONS: We demonstrate a landscape of confused reporting within the field of diabetes epidemiology where the term "prediction" is often incorrectly used to refer to association statistics. We propose guidelines for future reporting, and two major routes forward in terms of main analytic procedures and research goals: the explanatory route, which contributes to precision medicine, and the prediction route which contributes to personalized medicine.

Mitochondrial DNA deletion and sarcopenia.

PURPOSE: Accumulation of mitochondrial DNA deletions and the resultant impaired oxidative phosphorylation may play a pathogenic role in the mediation of age-related sarcopenia. METHODS: Twenty four participants of the New Mexico Aging Process Study were classified as normal lean (n = 15) or sarcopenic (n = 9) based on body composition determined by Dual Energy x-ray Absorptiometry. Complex I and Complex IV activities were measured in the skeletal muscle samples obtained from gastrocnemius muscle. A two-stage nested polymerase chain reaction strategy was used to identify the mitochondrial DNA deletions in the entire mitochondrial genome in the skeletal muscle samples. RESULTS: Although Complex I activity was not significantly different (5.5 +/- 0.9 vs. 4.6 +/- 0.7 mU/mg protein, P > 0.05), Complex IV activity was higher in sarcopenic subjects (1.4 +/- 0.3 vs. 1.0 +/- 0.1 mU/mg protein, P < 0.05). Mitochondrial DNA deletions were mostly located in the region of Complex I and spanned from nicotinamide adenine dinucleotide dehydrogenase 1 to nicotinamide adenine dinucleotide dehydrogenase 6. Deletions in the 8,577-10,407 bp and 10,233-11,249 bp regions were associated with a significant decrease in Complex I activity (P < 0.05 and P = 0.02, respectively). Total cumulative deletion, defined as the sum of individual length of deletions in a subject, was comparable in subjects with and without sarcopenia (1760 +/- 726 vs. 1782 +/- 888 bp, P > 0.05). The magnitude of mitochondrial DNA deletion, however, correlated positively with lean body mass (r = 0.43, P < 0.05). CONCLUSION: Thus, mitochondrial DNA deletions are common in elderly subjects and are negatively related to Complex I activity. The positive association between mitochondrial DNA deletions and lean body mass needs to be confirmed by studies in a larger study population.

Soluble CD14 levels, interleukin 6, and mortality among prevalent hemodialysis patients.

BACKGROUND: CD14 is a pattern-recognition receptor that has a central immunomodulatory role in proinflammatory signaling in response to a variety of ligands, including endotoxin. CD14 protein is present in 2 forms: soluble (sCD14) and membrane bound. Here, we studied the implications of increased sCD14 levels in hemodialysis patients. We hypothesized that sCD14 level increase may link to cytokine activation and protein-energy wasting, predisposing to increased mortality risk. STUDY DESIGN: Prospective observational study of prevalent hemodialysis patients. SETTING & PARTICIPANTS: 211 prevalent hemodialysis patients, median age of 65 years, with 29 months of vintage dialysis time followed up for mortality for a median of 31 months. PREDICTORS: Tertiles of baseline circulating sCD14 levels corresponding to less than 2.84, 2.85 to 3.62, and greater than 3.63 microg/mL. OUTCOME: The major outcome of interest was all-cause mortality. MEASUREMENTS: sCD14 and endotoxin, together with other markers of inflammation and protein-energy wasting. RESULTS: Median sCD14 level was 3.2 microg/mL (25th to 75th percentile, 2.7 to 3.9). sCD14 level correlated positively with C-reactive protein, interleukin 6, endotoxin, and pentraxin 3 levels and negatively with serum albumin level, muscle mass, and handgrip strength. Patients with increased sCD14 levels had lower body mass index and increased prevalence of muscle atrophy. Patients within the highest sCD14 tertile had a crude morality hazard ratio of 1.94 (95% confidence interval, 1.13 to 3.32) that persisted after adjustment for multiple confounders (hazard ratio, 3.11; 95% confidence interval, 1.49 to 6.46). In patients with persistent inflammation, the presence of a concurrent sCD14 level increase gradually increased mortality risk, but this effect was less than multiplicative and failed to show a statistical interaction. LIMITATIONS: Those inherent to an observational study. CONCLUSIONS: sCD14 level is associated with inflammation and protein-energy wasting in hemodialysis patients. It is a strong and independent predictor of mortality that warrants further assessment in the clinical setting regarding its usefulness as a complementary prognosticator to other general inflammatory markers.

The effect of glutamine infusion on the inflammatory response and HSP70 during human experimental endotoxaemia.

INTRODUCTION: Glutamine supplementation has beneficial effects on morbidity and mortality in critically ill patients, possibly in part through an attenuation of the proinflammatory cytokine response and a stimulation of heat shock protein (HSP)70. We infused either alanine-glutamine or saline during endotoxin challenge and measured plasma cytokines and HSP70 protein expression. METHODS: This crossover study, conducted in eight healthy young men, was double-blind, randomized and placebo-controlled. It was performed on 2 trial days, separated by a 4-week washout period. The volunteers received an infusion of alanine-glutamine at a rate of 0.025 g/(kg body weight x hour) or saline for 10 hours. After 2 hours, an intravenous bolus of Escherichia coli endotoxin (0.3 ng/kg) was administered. Blood samples were collected hourly for the following 8 hours. HSP70 protein content in isolated blood mononuclear cells (BMNCs) was measured by Western blotting. RESULTS: Plasma glutamine increased during alanine-glutamine infusion. Endotoxin reduced plasma glutamine during both trials, but plasma glutamine levels remained above baseline with alanine-glutamine supplementation. Endotoxin injection was associated with alterations in white blood cell and differential counts, tumour necrosis factor-alpha, IL-6, temperature and heart rate, but glutamine affected neither the endotoxin-induced change in these variables nor the expression of HSP70 in BMNCs. CONCLUSIONS: Endotoxin reduced plasma glutamine independently of alanine-glutamine infusion, but supplementation allows plasma levels to be maintained above baseline. Glutamine alters neither endotoxin-induced systemic inflammation nor early expression of HSP70 in BMNCs. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT 00780520.

Population-wide analysis of differences in disease progression patterns in men and women.

Sex-stratified medicine is a fundamentally important, yet understudied, facet of modern medical care. A data-driven model for how to systematically analyze population-wide, longitudinal differences in hospital admissions between men and women is needed. Here, we demonstrate a systematic analysis of all diseases and disease co-occurrences in the complete Danish population using the ICD-10 and Global Burden of Disease terminologies. Incidence rates of single diagnoses are different for men and women in most cases. The age at first diagnosis is typically lower for men, compared to women. Men and women share many disease co-occurrences. However, many sex-associated incongruities not linked directly to anatomical or genomic differences are also found. Analysis of multi-step trajectories uncover differences in longitudinal patterns, for example concerning injuries and substance abuse, cancer, and osteoporosis. The results point towards the need for an increased focus on sex-stratified medicine to elucidate the origins of the socio-economic and ethological differences.