Amplatzer Amulet Left Atrial Appendage Occluder Versus Watchman Device for Stroke Prophylaxis (Amulet IDE): A Randomized, Controlled Trial.

BACKGROUND: Percutaneous closure of the left atrial appendage (LAA) is an alternative to chronic oral anticoagulation to reduce stroke risk in patients with nonvalvular atrial fibrillation. The Amulet IDE trial (Amplatzer Amulet Left Atrial Appendage Occluder IDE Trial) was designed to evaluate the safety and effectiveness of the dual-seal mechanism of the Amulet LAA occluder compared with the Watchman device. METHODS: Patients with nonvalvular atrial fibrillation at increased risk of stroke were randomly assigned (1:1) to undergo percutaneous implantation of a LAA occluder with the Amulet occluder or Watchman device. The primary end points included safety (composite of procedure-related complications, all-cause death, or major bleeding at 12 months), effectiveness (composite of ischemic stroke or systemic embolism at 18 months), and the rate of LAA occlusion at 45 days. Prespecified secondary end points included a composite of all stroke, systemic embolism, or cardiovascular/unexplained death at 18 months, major bleeding at 18 months, and superiority test of the 3 primary end points. RESULTS: A total of 1878 patients were enrolled. The Amulet occluder was noninferior to the Watchman device for the primary safety end point (14.5% versus 14.7%; difference=-0.14 [95% CI, -3.42 to 3.13]; P<0.001 for noninferiority). Major bleeding and all-cause death were similar between groups (10.6% versus 10.0% and 3.9% versus 5.1%, respectively). Procedure-related complications were higher for the Amulet occluder (4.5% versus 2.5%), largely related to more frequent pericardial effusion and device embolization. The Amulet occluder was noninferior to the Watchman device for the primary effectiveness end point (2.8% versus 2.8%; difference=0.00 [95% CI, -1.55 to 1.55]; P<0.001 for noninferiority), and the composite of stroke, systemic embolism, or cardiovascular/unexplained death (5.6% versus 7.7%, difference=-2.12 [95% CI, -4.45 to 0.21]; P<0.001 for noninferiority). The rate of major bleeding was similar between groups (11.6% versus 12.3%; difference=-0.71 [95% CI, -3.72 to 2.31]; P=0.32 for superiority). LAA occlusion was higher for the Amulet occluder than for the Watchman device (98.9% versus 96.8%; difference=2.03 [95% CI, 0.41-3.66]; P<0.001 for noninferiority; P=0.003 for superiority). CONCLUSIONS: The Amulet occluder was noninferior for safety and effectiveness of stroke prevention for nonvalvular atrial fibrillation compared with the Watchman device and superior for LAA occlusion. Procedure-related complications were higher with the Amulet occluder and decreased with operator experience. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02879448.

Amplatzer Piccolo Occluder clinical trial for percutaneous closure of the patent ductus arteriosus in patients ≥700 grams.

OBJECTIVES: Characterize the safety and effectiveness of the Amplatzer Piccolo Occluder for patent ductus arteriosus (PDA) closure. BACKGROUND: The presence of a hemodynamically significant PDA has been associated with an increased risk of morbidity and mortality in children born premature. METHODS: This was a single arm, prospective, multicenter, non-randomized study to evaluate the Amplatzer Piccolo Occluder to treat PDA in patients ≥700 g. From June 2017 to February 2019, 200 patients were enrolled at nine centers, with 100 patients weighing ≤2 kg. Primary effectiveness endpoint was the rate of PDA closure at 6-month follow-up. Primary safety endpoint was the rate of major complications through 6 months. Secondary endpoint was rate of significant pulmonary or aortic obstruction through 6 months' follow-up. RESULTS: The implant success rate was 95.5% (191/200) overall and 99% in patients ≤2 kg (99/100). The primary effectiveness endpoint was achieved in 99.4% of implanted patients. Four patients experienced a primary safety endpoint event (2 transfusions, 1 hemolysis, and 1 aortic obstruction). There were no branch pulmonary artery obstructions. Five patients, all ≤2 kg, were noted to have worsening of tricuspid regurgitation (TR) after the procedure. None of the TR incidences manifested clinically. The Amplatzer Piccolo Occluder received FDA approval in January 2019 and became the first device approved for PDA closure in patients ≥700 g. CONCLUSIONS: This study supports the safety and effectiveness of the Amplatzer Piccolo Occluder, particularly in patients between 700 g and 2 kg where there is currently a significant unmet need in the United States. ClinicalTrials.gov identifier: NCT03055858.

Mitochondrial health and muscle plasticity after spinal cord injury.

Mitochondria are responsible for aerobic respiration and large-scale ATP production in almost all cells of the body. Their function is decreased in many neurodegenerative and cardiovascular disease states, in metabolic disorders such as type II diabetes and obesity, and as a normal component of aging. Disuse of skeletal muscle from immobilization or unloading triggers alterations of mitochondrial density and activity. Resultant mitochondrial dysfunction after paralysis, which precedes muscle atrophy, may augment subsequent release of reactive oxygen species leading to protein ubiquitination and degradation. Spinal cord injury is a unique form of disuse atrophy as there is a complete or partial disruption in tonic communication between the central nervous system (CNS) and skeletal muscle. Paralysis, unloading and disruption of CNS communication result in a rapid decline in skeletal muscle function and metabolic status with disruption in activity of peroxisome-proliferator-activated receptor-gamma co-activator 1 alpha and calcineurin, key regulators of mitochondrial health and function. External interventions, both acute and chronical with training using body-weight-assisted treadmill training or electrical stimulation have consistently demonstrated adaptations in skeletal muscle mitochondria, and expression of the genes and proteins required for mitochondrial oxidation of fats and carbohydrates to ATP, water, and carbon dioxide. The purpose of this mini-review is to highlight our current understanding as to how paralysis mechanistically triggers downstream regulation in mitochondrial density and activity and to discuss how mitochondrial dysfunction may contribute to skeletal muscle atrophy.

Plasma adiponectin levels are correlated with body composition, metabolic profiles, and mitochondrial markers in individuals with chronic spinal cord injury.

STUDY DESIGN: Cross-sectional design. OBJECTIVES: This study examined the relationships between circulating adiponectin levels, body composition, metabolic profile, and measures of skeletal muscle mitochondrial enzyme activity and biogenesis. SETTINGS: Clinical Research in a Medical Center. METHODS: Plasma adiponectin was quantified in 19 individuals with chronic spinal cord injury (SCI). Body composition was evaluated by dual x-ray absorptiometry and magnetic resonance imaging. Metabolic profile was assessed by basal metabolic rate (BMR), oxygen uptake (VO2), and intravenous glucose tolerance testing. Mitochondrial enzyme activity of skeletal muscle was obtained by spectrophotometric assays and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and 5' AMP-activated protein kinase (AMPK) protein expression was assessed by Western blots. RESULTS: Adiponectin was negatively related to both total and regional fat mass and positively related to lean mass and muscle mass. Furthermore, there were positive relationships between adiponectin and BMR (r = 0.52, P = 0.02) and VO2 (r = 0.73, P = 0.01). Furthermore, adiponectin was positively related to citrate synthase (r = 0.68, P = 0.002) and complex III activity (r = 0.57, P = 0.02). The relationships between adiponectin and body composition remained significant after accounting for age. The relationships between adiponectin, metabolic profile, and markers of mitochondria mass and activity were influenced by age. CONCLUSIONS: The study demonstrated that adiponectin is closely related to body composition and metabolic profile in persons with SCI and further supports mechanistic studies suggesting that adiponectin may stimulate mitochondrial biogenesis.

Skeletal muscle mitochondrial mass is linked to lipid and metabolic profile in individuals with spinal cord injury.

PURPOSE: Changes in metabolism and body composition after spinal cord injury (SCI) predispose individuals to obesity, type II diabetes, and cardiovascular disease. A link between lean mass and skeletal muscle mitochondrial mass has been reported but it is unknown how skeletal muscle mitochondrial mass and activity impact metabolic health. This study examined the relationship between skeletal muscle mitochondrial mass, activity and metabolic profile in individuals with chronic SCI. METHODS: Twenty-two men with motor complete SCI participated in the study. Citrate synthase (CS) and complex III (CIII) activity was measured in vastus lateralis biopsies. Metabolic profile was assessed by intravenous glucose tolerance test, basal metabolic rate (BMR), maximum oxygen uptake (VO2 peak) and blood lipid profile. RESULTS: Skeletal muscle CS activity was negatively related to the cholesterol:high density lipoprotein cholesterol (HDL-C) ratio and triglycerides (r = -0.60, p = 0.009; r = -0.64, p = 0.004, respectively). CS activity was positively related to insulin sensitivity and BMR (r = 0.67, p = 0.006; r = 0.64, p = 0.005, respectively). Similar relationships were found for CIII and metabolic profile, but not CIII normalized to CS. Many of the relationships between CS and metabolism remained significant when age, level of injury, or time since injury were accounted for. They also remained significant when CS activity was normalized to total lean mass. CONCLUSIONS: These results suggest that an increase in skeletal muscle mitochondrial mass is associated with improved metabolic health independent of age, level of injury, or time since injury in individuals with chronic SCI. This highlights the importance of maintaining and improving mitochondrial health in individuals with SCI.

Extraction of Phospholipids from Human Erythrocyte Membranes by Hemoglobin Oxidation Products.

This investigation examines oxidation conditions under which hemoglobin extracts membrane phospholipid from erythrocytes and model membranes. In erythrocytes made echinocytic with exogenous phospholipid, addition of hemoglobin oxidized with hydrogen peroxide (H2O2) or Vitamin C (conditions that result in the formation of significant quantities of choleglobin), but not ferricyanide (which produces predominantly methemoglobin), induced dose-dependent shape reversion to less echinocytic forms, consistent with extraction of phospholipids from the exofacial side of the membrane. Erythrocytes preloaded with radiolabeled phosphatidylcholine or NBD-labeled phosphatidylcholine, phosphatidylglycerol or phosphatidic acid, exhibited greatest extraction of radiolabel or fluorescence signal with exogenous hemoglobin oxidized via H2O2 or Vitamin C, but not ferricyanide. However, with NBD-phosphatidylserine (a preferential inner monolayer intercalator), significantly less extraction of labeled lipid occurred with oxidized hemoglobin prepared under all three oxidizing conditions. In dimyristoylphosphatidylcholine liposomes containing radiolabeled phosphatidylcholine, phosphatidylserine or phosphatidylethanolamine, subsequent addition of hemoglobin oxidized with H2O2 or Vitamin C extracted radiolabeled lipid with significantly greater efficiency than ferricyanide-treated hemoglobin, with enhanced extraction detectable at levels approaching physiological plasma oxidant concentrations. Radiolabeled lipid extraction was comparable for phospholipids containing saturated acyl chains between 12 and 18 carbons but diminished significantly for oleoyl-containing phospholipids. Hemoglobin dimerization occurred at very low levels with H2O2 treatment, and even lower levels with Vitamin C treatment, and thus did not correlate to the high efficiency and consistent levels of lipid extraction observed with these treatments. These findings indicate that choleglobin extracts lipids from cell membranes regardless of headgroup or acyl chain length, through a process of direct hydrophobic interaction with the membrane surface.

Interleukin-18 as a therapeutic target in acute myocardial infarction and heart failure.

Interleukin 18 (IL-18) is a proinflammatory cytokine in the IL-1 family that has been implicated in a number of disease states. In animal models of acute myocardial infarction (AMI), pressure overload, and LPS-induced dysfunction, IL-18 regulates cardiomyocyte hypertrophy and induces cardiac contractile dysfunction and extracellular matrix remodeling. In patients, high IL-18 levels correlate with increased risk of developing cardiovascular disease (CVD) and with a worse prognosis in patients with established CVD. Two strategies have been used to counter the effects of IL-18:IL-18 binding protein (IL-18BP), a naturally occurring protein, and a neutralizing IL-18 antibody. Recombinant human IL-18BP (r-hIL-18BP) has been investigated in animal studies and in phase I/II clinical trials for psoriasis and rheumatoid arthritis. A phase II clinical trial using a humanized monoclonal IL-18 antibody for type 2 diabetes is ongoing. Here we review the literature regarding the role of IL-18 in AMI and heart failure and the evidence and challenges of using IL-18BP and blocking IL-18 antibodies as a therapeutic strategy in patients with heart disease.

Interleukin-18 mediates interleukin-1-induced cardiac dysfunction.

Patients with heart failure (HF) have enhanced systemic IL-1 activity, and, in the experimental mouse model, IL-1 induces left ventricular (LV) systolic dysfunction. Whether the effects of IL-1 are direct or mediated by an inducible cytokine, such as IL-18, is unknown. Recombinant human IL-18-binding protein (IL-18BP) or an IL-18-blocking antibody (IL-18AB) was used to neutralize endogenous IL-18 after challenge with the plasma of patients with HF or with recombinant murine IL-1ß in adult male mice. Plasma levels of IL-18 and IL-6 (a key mediator of IL-1-induced systemic effects) and LV fractional shortening were measured in mice sedated with pentobarbital sodium (30-50 mg/kg). Mice with genetic deletion of IL-18 or IL-18 receptors were compared with matching wild-type mice. A group of mice received murine IL-18 to evaluate the effects on LV fractional shortening. Plasma from HF patients and IL-1ß induced LV systolic dysfunction that was prevented by pretreatment with IL-18AB or IL-18BP. IL-1ß failed to induce LV systolic dysfunction in mice with genetic deletion of IL-18 signaling. IL-1ß induced a significant increase in plasma IL-18 and IL-6 levels. Genetic or pharmacological inhibition of IL-18 signaling failed to block the induction of IL-6 by IL-1ß. In conclusion, IL-1 induces a release of active IL-18 in the mouse that mediates the LV systolic dysfunction but not the induction of IL-6. IL-18 blockade may therefore represent a novel and more targeted therapeutic approach to treat HF.

Approaches to Design an Efficient, Predictable Global Post-approval Change Management System that Facilitates Continual Improvement and Drug Product Availability.

The complexity and inter-connectedness of operating in a global world for drug product supply has become an undeniable reality, further underscored by the COVID-19 pandemic. For Post-Approval Changes (PACs) that are an inevitable part of a product's commercial life, the impact of the growing global regulatory complexity and related drug shortages has brought the Global PAC Management System to an inflection point in particular for companies that have their products marketed in many countries.This paper illustrates through data analyzed for the first time from 145,000 + PACs for 156 countries, collected by 18 global pharma companies over a 3-year period (2019-2021), how severe the problem of global regulatory complexity is. Only PACs requiring national regulatory agency (NRA) approval prior to implementation were included in the data set. 1 of the 156 country NRAs approved all submitted PACs within a period of 6 months. The 6-month timeline was chosen because it is the recommended review timeline for major changes in the WHO guidance for vaccines and biotherapeutic products. 10 out of the 156 (6%) countries had no more than 10% of the PACs reviewed and approved in > 6 months. In 33 (22%) countries more than half of the PACs took > 6 months for approval. It is rare that the same PAC is approved globally within 6 months as individual NRAs take from a few months to years (in some cases > 5 years) for their review.The global PAC management complexity has steadily grown over the past 20 years. Attempts thus far to solve this problem have not made any meaningful difference. Senior leaders and decision-makers across the interdependent components of the complex Global PAC Management System (industry and regulators) must come together and collaboratively manage the problem holistically with the objective of ensuring global drug product availability instead of continuing with distinct stakeholder or country-focused solutions, which can tend to worsen the problem.In this paper, the Chief Quality Officers (CQOs) from 18 of the largest innovator pharma companies (see Acknowledgements) are speaking with One-Voice-of-Quality for PACs (1VQ for PACs Initiative). They are recommending a set of 8 approaches to activate a holistic transformation of the Global PAC Management System. This article presents their view on the problem of global regulatory complexity for managing PACs, it's impact on continual improvement and the risk to drug product supply, as well as approaches that can help alleviate the problem.

Effects of nicotine on olfactogustatory incentives: preference, palatability, and operant choice tests.

INTRODUCTION: The use of additives in tobacco may capitalize on the incentive motivational properties of tastes and scents such as mint (menthol), vanilla, and strawberry. These incentives are intended to increase tobacco experimentation, but their salience may also be enhanced by the incentive amplifying effects of nicotine (NIC). The goal of the present studies was to investigate the potential interaction between the incentive amplifying effects of NIC and gustatory incentives. METHODS: One of two discriminable tastes (grape or cherry Kool-Aid®; 0.05% wt/vol; unsweetened) was paired with sucrose (20% wt/vol; conditioned stimulus [CS+]) in deionized water, whereas the other taste (CS-) was presented in deionized water. Experiment 1 investigated the effects of NIC pretreatment on preference for the CS+ versus CS- in 2-bottle choice tests. Experiment 2 investigated the effects of NIC on palatability of the CS+ and CS- using orofacial taste reactions. Experiment 3 investigated the effects of NIC on reinforcement by the CS+ and CS- using a concurrent choice operant task. RESULTS: NIC pretreatment robustly increased operant responding for the CS+ but did not alter responding for the CS- in the operant choice task (Experiment 3). However, NIC pretreatment did not alter intake or palatability of the CS+ or CS- (Experiments 1 and 2). CONCLUSIONS: NIC increases the reinforcing effects of gustatory incentive stimuli, even though these stimuli were not paired with NIC administration. The findings suggest that adding taste incentives to tobacco products may increase the attractiveness of these products to consumers and the probability of repeated use.

Prenatal Buprenorphine/Naloxone or Methadone Use on Neonatal Outcomes in Michigan.

Background Maternal opioid exposure during pregnancy has various effects on neonatal health. Buprenorphine/naloxone and methadone are examples of medications for opioid use disorder (MOUD) used for the treatment of opioid use disorder (OUD). Research comparing the impacts of these MOUD modalities on neonatal outcomes when used to treat pregnant people with OUD remains limited. We evaluated the differences in outcomes between neonates with in-utero exposure to buprenorphine/naloxone versus methadone. Methodology We performed a retrospective cohort chart review between October 15, 2008, and October 15, 2019, evaluating mother/neonate dyads at two medical centers in Michigan. The charts of female patients, aged 18+, with OUD and buprenorphine/naloxone or methadone treatment, were examined. The charts of the corresponding neonates were also examined. Multiple regression analysis was performed. Results In total, 343 mother/infant dyads were included: 99 patients were treated with buprenorphine/naloxone and 232 patients were treated with methadone. The buprenorphine/naloxone group had significant differences in maternal age, hepatitis status, asthma, gestational age in weeks, neonatal intensive care unit (NICU) length of stay (LOS), neonatal opioid withdrawal syndrome (NOWS) peak score, birth head circumference, and birth weight compared to the methadone group at baseline. Adjusted multivariable regression analysis demonstrated neonates with exposure to buprenorphine/naloxone had a NOWS peak score 3.079 points less (95% confidence interval (CI): -4.525, 1.633; p = 0.001) and NICU LOS 8.955 days less (95% CI: -14.399, -3.511; p = 0.001) than neonates exposed to methadone. Conclusions Neonates with in-utero exposure to buprenorphine/naloxone had significantly lower NOWS scores and shorter NICU LOS compared to neonates with in-utero exposure to methadone. These findings demonstrate that buprenorphine/naloxone is potentially a more favorable treatment for the reduction in metrics representing adverse neonatal outcomes in pregnant people with OUD than methadone.

Quantification of trunk and android lean mass using dual energy x-ray absorptiometry compared to magnetic resonance imaging after spinal cord injury.

OBJECTIVE: To determine whether dual energy x-ray absorptiometry (DXA) compared to magnetic resonance imaging (MRI) may accurately quantify trunk lean mass (LM) after chronic spinal cord injury (SCI) and to investigate the relationships between trunk LM, visceral adiposity, trunk fat mass and basal metabolic rate (BMR). DESIGN: Cross-sectional design and correlational analysis. SETTING: Research setting in a medical center. PARTICIPANTS: Twenty-two men with motor complete paraplegia (n = 14; T4-T11) and tetraplegia (n = 8; C5-C7) were recruited as part of a clinical trial. INTERVENTIONS: Not applicable. OUTCOME MEASURES: Trunk and android LM were measured using DXA. The volume of six trunk muscle groups were then measured using MRI to quantify trunk LM-MRI. Subcutaneous and visceral adipose tissue (VAT) cross-sectional areas were also measured using MRI. After overnight fast, BMR was evaluated using indirect calorimetry. RESULTS: Trunk LM-DXA (24 ± 3.3 kg) and android LM-DXA (3.6 ± 0.7 kg) overestimated (P < 0.0001) trunk LM-MRI (1.7 ± 0.5 kg). Trunk LM-MRI = 0.088* log (trunk LM-DXA)-0.415; r2=0.29, SEE= 0.44 kg, P = 0.007. Trunk LM-MRI = 1.53* android LM-DXA + 0.126; r2=0.26, SEE= 0.21 kg, P = 0.018. Percentage trunk LM-MRI was inversely related to VAT (r=-0.79, P < 0.0001) and trunk fat mass (r=-0.83, P < 0.001). Only trunk LM-DXA was related to BMR (r = 0.61, P = 0.002). Persons with tetraplegia have 13% smaller trunk muscle cross-sectional areas (P = 0.036) compared to those with paraplegia. CONCLUSIONS: Trunk LM-DXA and android LM-DXA overestimated trunk LM-MRI. Percentage trunk LM-MRI, but not LM-DXA, was inversely related to trunk central adiposity. The findings highlight the importance of exercising trunk LM to attenuate cardio-metabolic disorders after SCI.

Validation of a portable hearing assessment tool: Agilis Health Mobile Audiogram.

OBJECTIVES: To examine if the tablet-based Agilis Health Mobile Audiogram (Agilis Audiogram) is an effective and valid measure of hearing thresholds compared to a pure-tone audiogram in an adult and pediatric population. METHODS: Participants underwent an otologic exam, conventional audiometric evaluation and the self-administered Agilis Audiogram. We examined whether the difference of pure-tone average (PTA) between the two measurement techniques fell within the equivalence range of ±8 dB. The Agilis Audiogram was administered twice for each subject to assess test-retest reliability of the application. RESULTS: A total of 54 ears from 27 participants were evaluated. The average time to complete the self-administered Agilis Audiogram was 10 min. Among participants with normal hearing, the average PTA from conventional audiometric evaluation was 8.9 dB (±3.8) and the average PTA from the Agilis Audiogram was 8.5 dB (±4.5), with mean difference of 0.4 dB (±4.2; 95% CI -1.0 to 1.7 dB) falling within the equivalence range (-8 to 8 dB). Among participants with confirmed hearing loss, the average PTA was 22.5 dB (±17.1) from conventional audiometric evaluation and 24.3 dB (±16.6) from the Agilis Audiogram, with mean difference of -1.8 dB (±5.4; 95% CI -4.9 to 1.3 dB), falling within the equivalence range. Overall, there was a significant correlation between conventional audiometric evaluation and the Agilis Audiogram (Pearson correlation = 0.93; p < 0.001). CONCLUSION: Thresholds obtained by the Agilis Audiogram were found to be a valid measure of hearing among adults with normal hearing and children with hearing loss in the mild-moderate range.

Murine de novo methyltransferase Dnmt3a demonstrates strand asymmetry and site preference in the methylation of DNA in vitro.

CpG methylation is involved in a wide range of biological processes in vertebrates as well as in plants and fungi. To date, three enzymes, Dnmt1, Dnmt3a, and Dnmt3b, are known to have DNA methyltransferase activity in mouse and human. It has been proposed that de novo methylation observed in early embryos is predominantly carried out by the Dnmt3a and Dnmt3b methyltransferases, while Dntm1 is believed to be responsible for maintaining the established methylation patterns upon replication. Analysis of the sites methylated in vivo using the bisulfite genomic sequencing method confirms the previous finding that some regions of the plasmid are much more methylated by Dnmt3a than other regions on the same plasmid. However, the preferred targets of the enzyme cannot be determined due to the presence of other methylases, DNA binding proteins, and chromatin structure. To discern the DNA targets of Dnmt3a without these compounding factors, sites methylated by Dnmt3a in vitro were analyzed. These analyses revealed that the two cDNA strands have distinctly different methylation patterns. Dnmt3a prefers CpG sites on a strand in which it is flanked by pyrimidines over CpG sites flanked by purines in vitro. These findings indicate that, unlike Dnmt1, Dnmt3a most likely methylates one strand of DNA without concurrent methylation of the CpG site on the complementary strand. These findings also indicate that Dnmt3a may methylate some CpG sites more frequently than others, depending on the sequence context. Methylation of each DNA strand independently and with possible sequence preference is a novel feature among the known DNA methyltransferases.

Liver Adiposity and Metabolic Profile in Individuals with Chronic Spinal Cord Injury.

PURPOSE: To quantify liver adiposity using magnetic resonance imaging (MRI) and to determine its association with metabolic profile in men with spinal cord injury (SCI). MATERIALS AND METHODS: MRI analysis of liver adiposity by fat signal fraction (FSF) and visceral adipose tissue (VAT) was completed on twenty participants. Intravenous glucose tolerance test was conducted to measure glucose effectiveness (Sg) and insulin sensitivity (Si). Lipid panel, fasting glucose, glycated hemoglobin (HbA1c), and inflammatory cytokines were also analyzed. RESULTS: Average hepatic FSF was 3.7% ± 2.1. FSF was positively related to TG, non-HDL-C, fasting glucose, HbA1c, VAT, and tumor necrosis factor alpha (TNF-α). FSF was negatively related to Si and testosterone. FSF was positively related to VAT (r = 0.48, p = 0.032) and TNF-α (r = 0.51, p = 0.016) independent of age, level of injury (LOI), and time since injury (TSI). The associations between FSF and metabolic profile were independent of VAT. CONCLUSIONS: MRI noninvasively estimated hepatic adiposity in men with chronic SCI. FSF was associated with dysfunction in metabolic profile, central adiposity, and inflammation. Importantly, liver adiposity influenced metabolic profile independently of VAT. These findings highlight the significance of quantifying liver adiposity after SCI to attenuate the development of metabolic disorders.

Mitochondrial mass and activity as a function of body composition in individuals with spinal cord injury.

Spinal cord injury (SCI) is accompanied by deterioration in body composition and severe muscle atrophy. These changes put individuals at risk for insulin resistance, type II diabetes, and cardiovascular disease. To determine the relationships between skeletal muscle mitochondrial mass, activity, and body composition, 22 men with motor complete SCI were studied. Body composition assessment was performed using dual-energy X-ray absorptiometry and magnetic resonance imaging. Skeletal muscle biopsies were obtained from the vastus lateralis muscle to measure citrate synthase (CS) and complex III (CIII) activity. CS activity was inversely related to %body fat (r = -0.57, P = 0.013), %leg fat (r = -0.52, P = 0.027), %trunk fat (r = -0.54, P = 0.020), and %android fat (r = -0.54, P = 0.017). CIII activity was negatively related to %body fat (r = -0.58, P = 0.022) and %leg fat (r = -0.54, P = 0.037). Increased visceral adipose tissue was associated with decreased CS and CIII activity (r = -0.66, P = 0.004; r = -0.60, P = 0.022). Thigh intramuscular fat was also inversely related to both CS and CIII activity (r = -0.56, P = 0.026; r = -0.60, P = 0.024). Conversely, lean mass (r = 0.75, P = 0.0003; r = 0.65, P = 0.008) and thigh muscle cross-sectional area (CSA; r = 0.82, P = 0.0001; r = 0.84; P = 0.0001) were positively related to mitochondrial parameters. When normalized to thigh muscle CSA, many body composition measurements remained related to CS and CIII activity, suggesting that %fat and lean mass may predict mitochondrial mass and activity independent of muscle size. Finally, individuals with SCI over age 40 had decreased CS and CIII activity (P = 0.009; P = 0.004), suggesting a decrease in mitochondrial health with advanced age. Collectively, these findings suggest that an increase in adipose tissue and decrease in lean mass results in decreased skeletal muscle mitochondrial activity in individuals with chronic SCI.

Effects of Testosterone and Evoked Resistance Exercise after Spinal Cord Injury (TEREX-SCI): study protocol for a randomised controlled trial.

INTRODUCTION: Individuals with spinal cord injury (SCI) are at a lifelong risk of obesity and chronic metabolic disorders including insulin resistance and dyslipidemia. Within a few weeks of injury, there is a significant decline in whole body fat-free mass, particularly lower extremity skeletal muscle mass, and subsequent increase in fat mass (FM). This is accompanied by a decrease in anabolic hormones including testosterone. Testosterone replacement therapy (TRT) has been shown to increase skeletal muscle mass and improve metabolic profile. Additionally, resistance training (RT) has been shown to increase lean mass and reduce metabolic disturbances in SCI and other clinical populations. METHODS AND ANALYSIS: 26 individuals with chronic, motor complete SCI between 18 and 50 years old were randomly assigned to a RT+TRT group (n=13) or a TRT group (n=13). 22 participants completed the initial 16-week training phase of the study and 4 participants withdrew. 12 participants of the 22 completed 16 weeks of detraining. The TRT was provided via transdermal testosterone patches (4-6 mg/day). The RT+TRT group had 16 weeks of supervised unilateral progressive RT using surface neuromuscular electrical stimulation with ankle weights. This study will investigate the effects of evoked RT+TRT or TRT alone on body composition (muscle cross-sectional area, visceral adipose tissue, %FM) and metabolic profile (glucose and lipid metabolism) in individuals with motor complete SCI. Findings from this study may help in designing exercise therapies to alleviate the deterioration in body composition after SCI and decrease the incidence of metabolic disorders in this clinical population. ETHICS AND DISSEMINATION: The study is currently approved by the McGuire VA Medical Center and Virginia Commonwealth University. All participants read and signed approved consent forms. Results will be submitted to peer-reviewed journals and presented at national and international conferences. TRIAL REGISTRATION NUMBER: Pre-result, NCT01652040.

Skeletal muscle mitochondrial health and spinal cord injury.

Mitochondria are the main source of cellular energy production and are dynamic organelles that undergo biogenesis, remodeling, and degradation. Mitochondrial dysfunction is observed in a number of disease states including acute and chronic central or peripheral nervous system injury by traumatic brain injury, spinal cord injury (SCI), and neurodegenerative disease as well as in metabolic disturbances such as insulin resistance, type II diabetes and obesity. Mitochondrial dysfunction is most commonly observed in high energy requiring tissues like the brain and skeletal muscle. In persons with chronic SCI, changes to skeletal muscle may include remarkable atrophy and conversion of muscle fiber type from oxidative to fast glycolytic, combined with increased infiltration of intramuscular adipose tissue. These changes contribute to a proinflammatory environment, glucose intolerance and insulin resistance. The loss of metabolically active muscle combined with inactivity predisposes individuals with SCI to type II diabetes and obesity. The contribution of skeletal muscle mitochondrial density and electron transport chain activity to the development of the aforementioned comorbidities following SCI is unclear. A better understanding of the mechanisms involved in skeletal muscle mitochondrial dynamics is imperative to designing and testing effective treatments for this growing population. The current editorial will review ways to study mitochondrial function and the importance of improving skeletal muscle mitochondrial health in clinical populations with a special focus on chronic SCI.

Pharmacological properties of microneurotrophin drugs developed for treatment of amyotrophic lateral sclerosis.

Microneurotrophins (MNT's) are small molecule derivatives of dehydroepiandrosterone (DHEA) and do not have significant interactions with sex steroid receptors. MNT's retain high-affinity binding to protein tyrosine kinase (Trk) receptors and can mimic many pleiotropic actions of neurotrophin (NT) proteins on neurons. MNT's offer therapeutic potential for diseases such as amyotrophic lateral sclerosis (ALS) where motor neurons (MN) degenerate. MNT's cross artificial membranes mimicking the blood-brain barrier, are not major substrates for ABC (ATP-binding cassette) transporters and are metabolized rapidly by mouse but more slowly by human hepatocytes. A lead MNT (BNN27) and its mono-oxidation metabolites enter mouse brain rapidly. RNA-sequencing measured gene expression profiles of human H9eSC-(embryonic stem cell)-derived or CTL (control) subject iPSC-(induced pluripotential stem cell)-derived MN's exposed to NT proteins or MNT molecules. Expression ratios (relative to DMSO (dimethylsulfoxide) vehicle) were calculated, and the resulting top 500 gene lists were analyzed for Gene Ontology (GO) grouping using DAVID (Database for Annotation, Visualization and Integrated Discovery). The MNT's BNN20, BNN23, and BNN27 showed overlap of GO terms with NGF (nerve growth factor) and BDNF (brain-derived neurotrophic factor) in the H9eSC-derived MN's. In the iPSC-derived MN's two (BNN20, BNN27) showed overlap of GO terms with NGF or BDNF. Each NT protein had GO terms that did not overlap with any MNT in the MN cell lines.

RNAseq Analyses Identify Tumor Necrosis Factor-Mediated Inflammation as a Major Abnormality in ALS Spinal Cord.

ALS is a rapidly progressive, devastating neurodegenerative illness of adults that produces disabling weakness and spasticity arising from death of lower and upper motor neurons. No meaningful therapies exist to slow ALS progression, and molecular insights into pathogenesis and progression are sorely needed. In that context, we used high-depth, next generation RNA sequencing (RNAseq, Illumina) to define gene network abnormalities in RNA samples depleted of rRNA and isolated from cervical spinal cord sections of 7 ALS and 8 CTL samples. We aligned >50 million 2X150 bp paired-end sequences/sample to the hg19 human genome and applied three different algorithms (Cuffdiff2, DEseq2, EdgeR) for identification of differentially expressed genes (DEG's). Ingenuity Pathways Analysis (IPA) and Weighted Gene Co-expression Network Analysis (WGCNA) identified inflammatory processes as significantly elevated in our ALS samples, with tumor necrosis factor (TNF) found to be a major pathway regulator (IPA) and TNFα-induced protein 2 (TNFAIP2) as a major network "hub" gene (WGCNA). Using the oPOSSUM algorithm, we analyzed transcription factors (TF) controlling expression of the nine DEG/hub genes in the ALS samples and identified TF's involved in inflammation (NFkB, REL, NFkB1) and macrophage function (NR1H2::RXRA heterodimer). Transient expression in human iPSC-derived motor neurons of TNFAIP2 (also a DEG identified by all three algorithms) reduced cell viability and induced caspase 3/7 activation. Using high-density RNAseq, multiple algorithms for DEG identification, and an unsupervised gene co-expression network approach, we identified significant elevation of inflammatory processes in ALS spinal cord with TNF as a major regulatory molecule. Overexpression of the DEG TNFAIP2 in human motor neurons, the population most vulnerable to die in ALS, increased cell death and caspase 3/7 activation. We propose that therapies targeted to reduce inflammatory TNFα signaling may be helpful in ALS patients.