Effects of sustained release growth hormone treatment during the rehabilitation of adult severe burn survivors

C188-9, a specific inhibitor of STAT3 signaling, prevents thermal burn-induced skeletal muscle wasting in mice

Burn injury is the leading cause of death and disability worldwide and places a tremendous economic burden on society. Systemic inflammatory responses induced by thermal burn injury can cause muscle wasting, a severe involuntary loss of skeletal muscle that adversely affects the survival and functional outcomes of these patients. Currently, no pharmacological interventions are available for the treatment of thermal burn-induced skeletal muscle wasting. Elevated levels of inflammatory cytokines, such as interleukin-6 (IL-6), are important hallmarks of severe burn injury. The levels of signal transducer and activator of transcription 3 (STAT3)-a downstream component of IL-6 inflammatory signaling-are elevated with muscle wasting in various pro-catabolic conditions, and STAT3 has been implicated in the regulation of skeletal muscle atrophy. Here, we tested the effects of the STAT3-specific signaling inhibitor C188-9 on thermal burn injury-induced skeletal muscle wasting in vivo and on C2C12 myotube atrophy in vitro after the administration of plasma from burn model mice. In mice, thermal burn injury severity dependently increased IL-6 in the plasma and tibialis anterior muscles and activated the STAT3 (increased ratio of phospho-STAT3/STAT3) and ubiquitin-proteasome proteolytic pathways (increased Atrogin-1/MAFbx and MuRF1). These effects resulted in skeletal muscle atrophy and reduced grip strength. In murine C2C12 myotubes, plasma from burn mice activated the same inflammatory and proteolytic pathways, leading to myotube atrophy. In mice with burn injury, the intraperitoneal injection of C188-9 (50 mg/kg) reduced activation of the STAT3 and ubiquitin-proteasome proteolytic pathways, reversed skeletal muscle atrophy, and increased grip strength. Similarly, pretreatment of murine C2C12 myotubes with C188-9 (10 µM) reduced activation of the same inflammatory and proteolytic pathways, and ameliorated myotube atrophy induced by plasma taken from burn model mice. Collectively, these results indicate that pharmacological inhibition of STAT3 signaling may be a novel therapeutic strategy for thermal burn-induced skeletal muscle wasting.

Clinically established biodegradable long acting injectables: An industry perspective

Long acting injectable formulations have been developed to sustain the action of drugs in the body over desired periods of time. These delivery platforms have been utilized for both systemic and local drug delivery applications. This review gives an overview of long acting injectable systems that are currently in clinical use. These products are categorized in three different groups: biodegradable polymeric systems, including microparticles and implants; micro and nanocrystal suspensions and oil-based formulations. Furthermore, the applications of these drug delivery platforms for the management of various chronic diseases are summarized. Finally, this review addresses industrial challenges regarding the development of long acting injectable formulations.

Association between sarcopenia and levels of growth hormone and insulin-like growth factor-1 in the elderly

Background

Age-related sarcopenia is a serious global health issue in elderly individuals and for the community as it induces disability and significant economic burden. The purpose of the study is to understand the factors associated with sarcopenia and the role of growth hormone (GH) and insulin-like growth factor (IGF-1) in the occurrence of sarcopenia.

Methods

Elderly patients (n = 3276) were included in this cross-sectional study. Survey and measurement of body composition (bioelectrical impedance), grip strength, and step speed were performed according to the Asian Working Group on Sarcopenia (AWGS) diagnostic criteria. Hematological and hormonal indicators were compared between patients with and without sarcopenia in order to identify the associated factors.

Results

There were significant differences in the demographic parameters between the sarcopenia and non-sarcopenia groups (all P < 0.05). There were significant differences between the two groups regarding the blood levels of GH, IGF-1, testosterone (T), and mechanical growth factor (MGF) (all P < 0.001). Correlation analyses showed that the appendicular skeletal muscle mass (ASMI) was positively associated with gender and BMI, and with GH, T, IGF-1, MGF, BUN, Cr, and Hb levels, but negatively associated with HDL-C (all P < 0.05). Logistic multivariable regression analysis showed that IGF-1, MGF, BMI, and gender were independently associated with appendicular skeletal muscle mass (ASMI) (all P < 0.05).

Conclusions

GH and IGF-1 are associated with sarcopenia in the elderly. IGF-1 and MGF are independently associated with the reduction of skeletal muscle mass, along with BMI and gender.

The Long-Term Impact of Severe Burn Trauma on Musculoskeletal Health

Severe burn injury causes a profound stress response that leads to muscle and bone cachexia. Evidence suggests that these deficits persist for several months or even years after injury and are associated with growth delay, increased incidence of fractures, and increased hospital admissions for musculoskeletal disorders. Thus, there is an overwhelming need to determine the optimal acute and rehabilitative strategies to mitigate these deficits and improve quality of life for burn survivors. To date, there is limited research on the long-term impact of cachexia on functional performance and overall health, as well as on the lasting impact of pharmacological, nutritional, and exercise interventions. The aim of this review is to emphasize the long-term consequences of musculoskeletal cachexia and determine the best evidence-based strategies to attenuate it. We also underline important knowledge gaps that need to be addressed in order to improve care of burn survivors.

Relation Between Low Pulmonary Function and Skeletal Muscle Index in Burn Patients with Major Burn Injury and Smoke Inhalation: A Retrospective Study

This report is to evaluate the relation between pulmonary function, respiratory muscle strength, and skeletal muscle index (SMI) in patients with major burn injury and smoke inhalation. A total of 54 inhalation burn patients were analyzed. Appendicular skeletal muscle mass (ASM) is a sum of the muscle mass of both arms and legs. SMI is adjusting for body size using body mass index (ASM/BMI). Spirometry was performed to evaluate pulmonary function. Pulmonary function tests included peak cough flow (PCF), forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), forced expiratory flow rate between 25 and 75% of the FVC (FEF 25–75), FEV1/FVC ratio expressed as a percentage (FEV1/FVC %), peak expiratory flow (PEF), and maximum voluntary ventilation. Expiratory and inspiratory muscle strengths were measured. The relations between pulmonary function, respiratory muscle strength, and SMI were investigated. SMI showed significant correlations with PCF (r = 0.34 and P = 0.02), FVC (r = 0.55 and P &lt; 0.001), FEV1 (r = 0.45 and P = 0.001), and PEF (r = 0.35 and P = 0.01). In multiple regression analysis including age, TBSA, duration of mechanical ventilation, and postburn days studied, SMI was significantly related to FVC, PCF, FEV1, FEV1/FVC, and PEF (P &lt; 0.001, P = 0.02, P = 0.001, P = 0.04, and P = 0.03). Pulmonary function tests are significantly related to SMI in patients with major burn injury and smoke inhalation. Intensive treatment on muscle wasting in patients with burn injury has been proven to be important for improving pulmonary functions.

Anabolic and anticatabolic agents used in burn care: What is known and what is yet to be learned

Major thermal injury induces profound metabolic derangements secondary to an inflammatory "stress-induced" hormonal environment. Several pharmacological interventions have been tested in an effort to halt the hypermetabolic response to severe burns. Insulin, insulin growth factor 1, insulin growth factor binding protein 3, metformin, human growth hormone, thyroid hormones, testosterone, oxandrolone, and propranolol, among others, have been proposed to have anabolic or anticatabolic effects. The aim of this broad analysis of pharmacological interventions was to raise awareness of treatment options and to help establishing directions for future clinical research efforts. A PubMed search was conducted on the anabolic and anticatabolic agents used in burn care. One hundred and thirty-five human studies published between 1999 and 2017 were included in this review. The pharmacological properties, rationale for the treatments, efficacy considerations and side effect profiles are summarized in the article. Many of the drugs tested for investigational purposes in the severely thermally injured are not yet gold-standard therapies in spite of their potential benefit. Propranolol and oxandrolone have shown great promise but further evidence is still needed to clarify their potential use for anabolic and anticatabolic purposes.

Systematic review of clinical outcome reporting in randomised controlled trials of burn care

INTRODUCTION

Systematic reviews collate trial data to provide evidence to support clinical decision-making. For effective synthesis, there must be consistency in outcome reporting. There is no agreed set of outcomes for reporting the effect of burn care interventions. Issues with outcome reporting have been identified, although not systematically investigated. This study gathers empirical evidence on any variation in outcome reporting and assesses the need for a core outcome set for burn care research.

METHODS

Electronic searches of four search engines were undertaken from January 2012 to December 2016 for randomised controlled trials (RCTs), using medical subject headings and free text terms including 'burn', 'scald' 'thermal injury' and 'RCT'. Two authors independently screened papers, extracted outcomes verbatim and recorded the timing of outcome measurement. Duplicate outcomes (exact wording ± different spelling), similar outcomes (albumin in blood, serum albumin) and identical outcomes measured at different times were removed. Variation in outcome reporting was determined by assessing the number of unique outcomes reported across all included trials. Outcomes were classified into domains. Bias was reduced using five researchers and a patient working independently and together.

RESULTS

147 trials were included, of which 127 (86.4%) were RCTs, 13 (8.8%) pilot studies and 7 (4.8%) RCT protocols. 1494 verbatim clinical outcomes were reported; 955 were unique. 76.8% of outcomes were measured within 6 months of injury. Commonly reported outcomes were defined differently. Numbers of unique outcomes per trial varied from one to 37 (median 9; IQR 5,13). No single outcome was reported across all studies demonstrating inconsistency of reporting. Outcomes were classified into 54 domains. Numbers of outcomes per domain ranged from 1 to 166 (median 11; IQR 3,24).

CONCLUSIONS

This review has demonstrated heterogeneity in outcome reporting in burn care research which will hinder amalgamation of study data. We recommend the development of a Core Outcome Set.

PROSPERO REGISTRATION NUMBER

CRD42017060908.

CDPBC: A Software Application for Estimation of Concentration Dependent Plasma Binding Capacity of Small Molecule

Drug-plasma binding (DPB) is an important aspect during pharmacokinetics (PK) studies. DPB of small molecule cannot be evaluated through computational means. Here we present CDPBC; a standalone application for evaluation of small molecule for its capacity (concentration dependent) of binding with plasma proteins. This application is freely available at URL (https://github.com/undwive di/CDPBC.git). The application is enriched with evaluation of five major proteins of plasma. Input for application is a docked complex against the suggested PDBs of plasma proteins. As part of the analysis, software compares interaction of query compound with control compound. Main output comes as plot as well as table displaying percentage of binding in reference of concentration gradient of small molecule used in docking. The application is an advanced add-on component to ADME analysis of small molecules as well as lead optimization.

Resistance training for rehabilitation after burn injury: A systematic literature review & meta-analysis

BACKGROUND/AIM

Resistance training is beneficial for rehabilitation in many clinical conditions, though this has not been systematically reviewed in burns. The objective was to determine the effectiveness of resistance training on muscle strength, lean mass, function, quality of life and pain, in children and adults after burn injury.

METHODS

Medline & EMBASE, PubMed, CINAHL and CENTRAL were searched from inception to October 2016. Studies were identified that implemented resistance training in rehabilitation. Data were combined and included in meta-analyses for muscle strength and lean mass. Otherwise, narrative analysis was completed. The quality of evidence for each outcome was summarised and rated using the GRADE framework.

RESULTS

Eleven studies matched our inclusion criteria. Primary analysis did not demonstrate significant improvements for increasing muscle strength (SMD 0.74, 95% CI -0.02 to 1.50, p=0.06). Sensitivity analysis to correct an apparent anomaly in published data suggested a positive effect (SMD 0.37, 95% CI 0.08-0.65, p=0.01). Psychological quality of life demonstrated benefit from training (MD=25.3, 95% CI 3.94-49.7). All studies were rated as having high risk of bias. The quality of the evidence was rated as low or very low.

CONCLUSION

Further research with robust methodology is recommended to assess the potential benefit suggested in this review.

Nutrition and metabolism in burn patients

Severe burn causes significant metabolic derangements that make nutritional support uniquely important and challenging for burned patients. Burn injury causes a persistent and prolonged hypermetabolic state and increased catabolism that results in increased muscle wasting and cachexia. Metabolic rates of burn patients can surpass twice normal, and failure to fulfill these energy requirements causes impaired wound healing, organ dysfunction, and susceptibility to infection. Adequate assessment and provision of nutritional needs is imperative to care for these patients. There is no consensus regarding the optimal timing, route, amount, and composition of nutritional support for burn patients, but most clinicians advocate for early enteral nutrition with high-carbohydrate formulas.

Nutritional support must be individualized, monitored, and adjusted throughout recovery. Further investigation is needed regarding optimal nutritional support and accurate nutritional endpoints and goals.

Nutrition and metabolism in burn patients

Severe burn causes significant metabolic derangements that make nutritional support uniquely important and challenging for burned patients. Burn injury causes a persistent and prolonged hypermetabolic state and increased catabolism that results in increased muscle wasting and cachexia. Metabolic rates of burn patients can surpass twice normal, and failure to fulfill these energy requirements causes impaired wound healing, organ dysfunction, and susceptibility to infection. Adequate assessment and provision of nutritional needs is imperative to care for these patients. There is no consensus regarding the optimal timing, route, amount, and composition of nutritional support for burn patients, but most clinicians advocate for early enteral nutrition with high-carbohydrate formulas. Nutritional support must be individualized, monitored, and adjusted throughout recovery. Further investigation is needed regarding optimal nutritional support and accurate nutritional endpoints and goals.

The metabolic stress response to burn trauma: current understanding and therapies

Major burns provoke a profound stress response, which is unrivalled in terms of its magnitude and duration. Evidence suggests that the pathophysiological stress response to severe burn trauma persists for several years after injury. Thus, there is a pressing need for novel strategies that mitigate this response and restore normal metabolic function in patients with burns. This is the first in a Series of three papers about the care of people with burns. In this paper, we review the current knowledge of the stress response to burn trauma, with a focus on hypermetabolism, muscle wasting, and stress-induced diabetes. We highlight recent developments and important knowledge gaps that need to be pursued to develop novel therapeutic strategies to improve outcomes in burn survivors.