Protective effect of Growth Hormone-Releasing Hormone agonist in bacterial toxin-induced pulmonary barrier dysfunction

Growth hormone-releasing hormone antagonist MIA-602 inhibits inflammation induced by SARS-CoV-2 spike protein and bacterial lipopolysaccharide synergism in macrophages and human peripheral blood mononuclear cells

COVID-19 is characterized by an excessive inflammatory response and macrophage hyperactivation, leading, in severe cases, to alveolar epithelial injury and acute respiratory distress syndrome. Recent studies have reported that SARS-CoV-2 spike (S) protein interacts with bacterial lipopolysaccharide (LPS) to boost inflammatory responses in vitro, in macrophages and peripheral blood mononuclear cells (PBMCs), and in vivo. The hypothalamic hormone growth hormone-releasing hormone (GHRH), in addition to promoting pituitary GH release, exerts many peripheral functions, acting as a growth factor in both malignant and non-malignant cells. GHRH antagonists, in turn, display potent antitumor effects and antinflammatory activities in different cell types, including lung and endothelial cells. However, to date, the antinflammatory role of GHRH antagonists in COVID-19 remains unexplored. Here, we examined the ability of GHRH antagonist MIA-602 to reduce inflammation in human THP-1-derived macrophages and PBMCs stimulated with S protein and LPS combination. Western blot and immunofluorescence analysis revealed the presence of GHRH receptor and its splice variant SV1 in both THP-1 cells and PBMCs. Exposure of THP-1 cells to S protein and LPS combination increased the mRNA levels and protein secretion of TNF-α and IL-1β, as well as IL-8 and MCP-1 gene expression, an effect hampered by MIA-602. Similarly, MIA-602 hindered TNF-α and IL-1β secretion in PBMCs and reduced MCP-1 mRNA levels. Mechanistically, MIA-602 blunted the S protein and LPS-induced activation of inflammatory pathways in THP-1 cells, such as NF-κB, STAT3, MAPK ERK1/2 and JNK. MIA-602 also attenuated oxidative stress in PBMCs, by decreasing ROS production, iNOS and COX-2 protein levels, and MMP9 activity. Finally, MIA-602 prevented the effect of S protein and LPS synergism on NF-кB nuclear translocation and activity. Overall, these findings demonstrate a novel antinflammatory role for GHRH antagonists of MIA class and suggest their potential development for the treatment of inflammatory diseases, such as COVID-19 and related comorbidities.

GHRH agonist MR-409 protects β-cells from streptozotocin-induced diabetes

Patients with type 1 diabetes (T1D) suffer from insufficient functional β-cell mass, which results from infiltration of inflammatory cells and cytokine-mediated β-cell death. Previous studies demonstrated the beneficial effects of agonists of growth hormone-releasing hormone receptor (GHRH-R), such as MR-409 on preconditioning of islets in a transplantation model. However, the therapeutic potential and protective mechanisms of GHRH-R agonists on models of T1D diabetes have not been explored. Using in vitro and in vivo models of T1D, we assessed the protective propertie of the GHRH agonist, MR409 on β-cells. The treatment of insulinoma cell lines and rodent and human islets with MR-409 induces Akt signaling by induction of insulin receptor substrate 2 (IRS2), a master regulator of survival and growth in β-cells, in a PKA-dependent manner. The increase in cAMP/PKA/CREB/IRS2 axis by MR409 was associated with decrease in β-cell death and improved insulin secretory function in mouse and human islets exposed to proinflammatory cytokines. The assessment of the effects of GHRH agonist MR-409 in a model of T1D induced by low-dose streptozotocin showed that mice treated with MR-409 exhibited better glucose homeostasis, higher insulin levels, and preservation of β-cell mass. Increased IRS2 expression in β-cells in the group treated with MR-409 corroborated the in vitro data and provided evidence for the underlying mechanism responsible for beneficial effects of MR-409 in vivo. Collectively, our data show that MR-409 is a novel therapeutic agent for the prevention and treatment of β-cells death in T1D.

Scavenging of reactive oxygen species can adjust the differentiation of tendon stem cells and progenitor cells and prevent ectopic calcification in tendinopathy

Tendinopathy is a common disorder that leads to pain and impaired quality of life. Recent studies revealed that osteogenic differentiation of tendon stem/progenitor cells (TSPCs) played an important role in the pathogenesis of tendon calcification and tendinopathy. In this study, we found that the growth hormone-releasing hormone agonist (GA) can prevent matrix degradation and osteogenic differentiation in TSPCs. As oxidative stress is a key factor in the osteogenic differentiation of TSPCs, we used bovine serum albumin/heparin nanoparticles (BHNPs), which have biocompatibility and drug loading capacity, to scavenge reactive oxygen species (ROS) and achieve sustained release of GA at the site of inflammation. The newly developed BHNPs@GA had a synergetic effect on reducing ROS production in TSPCs. In addition, BHNPs@GA effectively inhibited tendon calcification and promoted collagen formation in a rat model of tendinopathy. Focusing on the ROS underlying the differentiation and dedifferentiation of TSPCs, this work demonstrated that sustained release of GA targeting ROS and ectopic ossification is a practical therapeutic strategy for treating tendinopathy. STATEMENT OF SIGNIFICANCE: Osteogenic differentiation of tendon stem/progenitor cells (TSPCs) plays an important role in the pathogenesis of ectopic calcification in tendinopathy. In this study, we found that growth hormone-releasing hormone agonist (GA) can reduce reactive oxygen species (ROS) production and adjust TSPCs differentiation. Bovine serum albumin/heparin nanoparticles (BHNPs) were developed to encapsulate GA and achieve sustained release of GA at the site of inflammation. The developed compound, BHNPs@GA, with a synergistic effect of inhibiting ROS and thus, can effectively adjust TSPCs differentiation, inhibit tendon calcification, and promote collagen formation in tendinopathy. This study highlighted the role of ROS underlying the differentiation and dedifferentiation of TSPCs in tendinopathy, and findings may help to identify new therapeutic targets and develop novel strategy for treating tendinopathy.

A thermosensitive, reactive oxygen species-responsive, MR409-encapsulated hydrogel ameliorates disc degeneration in rats by inhibiting the secretory autophagy pathway

Lumbar disc degeneration is a common cause of chronic low back pain and an important contributor to various degenerative lumbar spinal disorders. However, currently there is currently no effective therapeutic strategy for treating disc degeneration. The pro-inflammatory cytokine interleukin-1β (IL-1β) mediates disc degeneration by inducing apoptotic death of nucleus pulposus (NP) cells and degradation of the NP extracellular matrix. Here, we confirmed that extracellular secretion of IL-1β via secretory autophagy contributes to disc degeneration, and demonstrate that a thermosensitive reactive oxygen species (ROS)-responsive hydrogel loaded with a synthetic growth hormone-releasing hormone analog (MR409) can protect against needle puncture-induced disc degeneration in rats.

Methods: The expression levels of proteins related to secretory autophagy such as tripartite motif-containing 16 (TRIM16) and microtubule-associated protein light chain 3B (LC3B) were examined in human and rat disc tissues by histology and immunofluorescence. The effects of TRIM16 expression level on IL-1β secretion were examined in THP-1 cells transfected with TRIM16 plasmid or siRNA using ELISA, immunofluorescence, and immunoblotting. The in vitro effects of MR409 on IL-1β were examined in THP-1 cells and primary rat NP cells using ELISA, immunofluorescence, immunoblotting, and qRT-PCR. Further, MR409 was subcutaneously administered to aged mice to test its efficacy against disc degeneration using immunofluorescence, X-ray, micro-CT, and histology. To achieve controllable MR409 release for intradiscal use, MR409 was encapsulated in an injectable ROS-responsive thermosensitive hydrogel. Viscosity, rheological properties, release profile, and biocompatibility were evaluated. Thereafter, therapeutic efficacy was assessed in a needle puncture-induced rat model of disc degeneration at 8 and 12 weeks post-operation using X-ray, magnetic resonance (MR) imaging, histological analysis, and immunofluorescence.

Results: Secretory autophagy-related proteins TRIM16 and LC3B were robustly upregulated in degenerated discs of both human and rat. Moreover, while upregulation of TRIM16 facilitated, and knockdown of TRIM16 suppressed, secretory autophagy-mediated IL-1β secretion from THP-1 cells under oxidative stress, MR409 inhibited ROS-induced secretory autophagy and IL-1β secretion by THP-1 cells as well as IL-1β-induced pro-inflammatory and pro-catabolic effects in rat NP cells. Daily subcutaneous injection of MR409 inhibited secretory autophagy and ameliorated age-related disc degeneration in mice. The newly developed ROS-responsive MR409-encapsulated hydrogel provided a reliable delivery system for controlled MR409 release, and intradiscal application effectively suppressed secretory autophagy and needle puncture-induced disc degeneration in rats.

Conclusion: Secretory autophagy and associated IL-1β secretion contribute to the pathogenesis of disc degeneration, and MR409 can effectively inhibit this pathway. The ROS-responsive thermosensitive hydrogel encapsulated with MR409 is a potentially efficacious treatment for disc degeneration.

Effect of Intratracheal Instillation of ZnO Nanoparticles on Acute Lung Inflammation Induced by Lipopolysaccharides in Mice

Although studies have shown toxic effects of zinc oxide (ZnO) particles following inhalation, additional effects on injured lungs, which are characterized by dysfunction of the alveolar-capillary barriers, remain uncharacterized. To explore these additional effects, nano-sized ZnO (nZnO) and bulk-sized ZnO were applied to lipopolysaccharide (LPS)-challenged mouse lungs, which were used as a disease model of acute lung inflammation. An elevated Zn2+ concentration was detected in lung tissue after LPS plus nZnO exposure. Exposure to nZnO in LPS-challenged mice resulted in higher total cell number, proportion of neutrophils, and total protein level in bronchoalveolar lavage fluid. Intratracheal instillation of nZnO intensively aggravated LPS-induced lung inflammation that was accompanied by enhanced expression of interleukin-1β, interleukin-6, monocyte chemotactic protein-1α, and granulocyte-macrophage colony stimulating factor. Catalase, glutathione, and total superoxide dismutase levels were significantly decreased, and the malondialdehyde level was obviously increased in the LPS plus nZnO group. 8-Hydroxyguanosine, a marker for DNA damage, was highly concentrated in the lungs from the LPS plus nZnO group. Furthermore, nZnO increased lung apoptosis in an acute lung inflammation model. Taken together, this evidence indicates that nZnO aggravates lung inflammation related to LPS. This enhancement effect may be mediated via oxidative stress, which can lead to DNA damage and apoptosis. This work is important because of the ever-increasing exposure of people to ZnO nanoparticles in industry. The identification of the toxic effects of nZnO and possible mechanisms revealed in this study provide valuable information for future studies.

Biomechanical Forces and Oxidative Stress: Implications for Pulmonary Vascular Disease

Significance: Oxidative stress in the cell is characterized by excessive generation of reactive oxygen species (ROS). Superoxide (O₂^-) and hydrogen peroxide (H₂O₂) are the main ROS involved in the regulation of cellular metabolism. As our fundamental understanding of the underlying causes of lung disease has increased it has become evident that oxidative stress plays a critical role. Recent Advances: A number of cells in the lung both produce, and respond to, ROS. These include vascular endothelial and smooth muscle cells, fibroblasts, and epithelial cells as well as the cells involved in the inflammatory response, including macrophages, neutrophils, eosinophils. The redox system is involved in multiple aspects of cell metabolism and cell homeostasis. Critical Issues: Dysregulation of the cellular redox system has consequential effects on cell signaling pathways that are intimately involved in disease progression. The lung is exposed to biomechanical forces (fluid shear stress, cyclic stretch, and pressure) due to the passage of blood through the pulmonary vessels and the distension of the lungs during the breathing cycle. Cells within the lung respond to these forces by activating signal transduction pathways that alter their redox state with both physiologic and pathologic consequences. Future Directions: Here, we will discuss the intimate relationship between biomechanical forces and redox signaling and its role in the development of pulmonary disease. An understanding of the molecular mechanisms induced by biomechanical forces in the pulmonary vasculature is necessary for the development of new therapeutic strategies.

Direct factor Xa inhibition attenuates acute lung injury progression via modulation of the PAR-2/NF-κB signaling pathway

The role of coagulation in acute lung injury (ALI) remains unclear. As factor Xa-dependent protease-activated receptor 2 (PAR-2) is reported to be an important target in blood coagulation and other processes, an inhibitor of factor Xa, rivaroxaban, was tested in vivo in C57BL/6 mice with ALI induced by intratracheal injections of lipopolysaccharide (LPS) and in vitro in LPS-stimulated human umbilical vein endothelial cells. Plasma concentrations and coagulation indices were measured in mice fed normal chow or chow containing rivaroxaban (0.2 or 0.4 mg/g) for 10 days. The rivaroxaban-treated mice had significantly reduced neutrophil sequestration with preservation of the lung tissue architecture compared with that in the untreated controls. The levels of tumor necrosis factor alpha, interleukin 1 beta, and interleukin 6, as well as total protein and Evans blue concentrations, were all significantly reduced in bronchoalveolar lavage fluid from mice treated with rivaroxaban. Rivaroxaban treatment also ameliorated the LPS-induced PAR-2 increase and nuclear factor kappa B (NF-κB) activation. In vitro, cells treated with rivaroxaban had higher cell viability with an attenuation of LPS-induced increases in membrane permeability and proinflammatory cytokine levels, as well as reduced apoptosis. Furthermore, rivaroxaban inhibited the phosphorylation of TAK1 and p65. These data show that rivaroxaban attenuates ALI and inflammation by inhibiting the PAR-2/NF-κB signaling pathway.

Regulation of Vascular Calcification by Growth Hormone-Releasing Hormone and Its Agonists

RATIONALE

Vascular calcification (VC) is a marker of the severity of atherosclerotic disease. Hormones play important roles in regulating calcification; estrogen and parathyroid hormones exert opposing effects, the former alleviating VC and the latter exacerbating it. To date no treatment strategies have been developed to regulate clinical VC.

OBJECTIVE

The objective of this study was to investigate the effect of growth hormone-releasing hormone (GHRH) and its agonist (GHRH-A) on the blocking of VC in a mouse model.

METHODS AND RESULTS

Young adult osteoprotegerin-deficient mice were given daily subcutaneous injections of GHRH-A (MR409) for 4 weeks. Significant reductions in calcification of the aortas of MR409-treated mice were paralleled by markedly lower alkaline phosphatase activity and a dramatic reduction in the expression of transcription factors, including the osteogenic marker gene Runx2 and its downstream factors, osteonectin and osteocalcin. The mechanism of action of GHRH-A was dissected in smooth muscle cells isolated from human and mouse aortas. Calcification of smooth muscle cells induced by osteogenic medium was inhibited in the presence of GHRH or MR409, as evidenced by reduced alkaline phosphatase activity and Runx2 expression. Inhibition of calcification by MR409 was partially reversed by MIA602, a GHRH antagonist, or a GHRH receptor-selective small interfering RNA. Treatment with MR409 induced elevated cytosolic cAMP and its target, protein kinase A which in turn blocked nicotinamide adenine dinucleotide phosphate oxidase activity and reduced production of reactive oxygen species, thus blocking the phosphorylation of nuclear factor κB (p65), a key intermediate in the ligand of receptor activator for nuclear factor-κ B-Runx2/alkaline phosphatase osteogenesis program. A protein kinase A-selective small interfering RNA or the chemical inhibitor H89 abolished these beneficial effects of MR409.

CONCLUSIONS

GHRH-A controls osteogenesis in smooth muscle cells by targeting cross talk between protein kinase A and nuclear factor κB (p65) and through the suppression of reactive oxygen species production that induces the Runx2 gene and alkaline phosphatase. Inflammation-mediated osteogenesis is thereby blocked. GHRH-A may represent a new pharmacological strategy to regulate VC.

Endothelial Cdc42 deficiency impairs endothelial regeneration and vascular repair after inflammatory vascular injury

Background

Endothelial cell (EC) regeneration is essential for inflammation resolution and vascular integrity recovery after inflammatory vascular injury. Cdc42 is a central regulator of cell survival and vessel formation in EC development. However, it is unknown that whether Cdc42 could be a regulating role of EC repair following the inflammatory injury in the lung. The study sought to test the hypothesis that Cdc42 is required for endothelial regeneration and vascular integrity recovery after LPS-induced inflammatory injury.

Methods and results

The role of Cdc42 for the regulation of pulmonary vascular endothelial repair was tested in vitro and in vivo. In LPS-induced acute lung injury (ALI) mouse models, knockout of the Cdc42 gene in ECs increased inflammatory cell infiltration and pulmonary vascular leakage and inhibited vascular EC proliferation, which eventually resulted in more severe inflammatory lung injury. In addition, siRNA-mediated knockdown of Cdc42 protein on ECs disrupted cell proliferation and migration and tube formation, which are necessary processes for recovery after inflammatory vascular injury, resulting in inflammatory vascular injury recovery defects.

Conclusion

We found that Cdc42 deficiency impairs EC function and regeneration, which are crucial in the post-inflammatory vascular injury repair process. These findings indicate that Cdc42 is a potential target for novel treatments designed to facilitate endothelial regeneration and vascular repair in inflammatory pulmonary vascular diseases, such as ALI/ARDS.

Electronic supplementary material

The online version of this article (10.1186/s12931-018-0729-8) contains supplementary material, which is available to authorized users.

Proteinase-Activated Receptor-2 Modulates Ve-Cadherin Expression to Affect Human Vascular Endothelial Barrier Function

Published data indicate that the protease-activated receptor (PAR) 2 is involved in the pathogenesis of some cardiovascular diseases; the underlying mechanism is to be further investigated. Ve-cadherin is a critical molecule in maintaining the endothelial barrier integrity. This study aims to investigate the role of PAR2 activation in compromising the cardiac endothelial barrier function. In this study, human umbilical vein endothelial cells (Huvec cells) were cultured into monolayers using as an in vitro model of barrier function. The transepithelial electric resistance (TER) and permeability to dextran were assessed as indicators of barrier function. The expression of Ve-cadherin in Huvec cells was assessed by real-time RT-PCR, Western blotting, and chromatin immunoprecipitation. The results showed that exposure to tryptase in the culture, the barrier function of the Huvec monolayers, was markedly compromised; the levels of Ve-cadherin, one of the tight junction proteins, were suppressed as well. This was mimicked by exposing Huvec monolayers to the active PAR2 peptides (PAR2AP). After exposing to PAR2AP, the levels of histone deacetylase (HDAC)11 were increased in the Huvec cells. HDAC11 formed a complex with the transcription factor of Ve-cadherin to attenuate the Erg gene transcription activities and suppressed the expression of Ve-cadherin. In conclusion, activation of PAR2 compromises the vascular endothelial barrier function by suppressing the expression of Ve-cadherin. J. Cell. Biochem. 118: 4587-4593, 2017. © 2017 Wiley Periodicals, Inc.

Method for the Culture of Mouse Pulmonary Microvascular Endothelial Cells

Pulmonary microvascular endothelial cells (ECs) are integral to the alveoli-capillary barrier of the lung. The EC barrier integrity is known to be disrupted in severe lung diseases such as acute respiratory distress syndrome (ARDS), pneumonia and pulmonary edema. Mice are commonly used to model these diseases, dictating an increasingly high demand for murine ECs isolation and culture. Despite the significant number of protocols for the culture of various types of murine cells, the isolation of microvascular endothelial cells remains a challenging procedure. In our manuscript we developed adetailed step-by-step refined method for isolation murine pulmonary microvascular ECs for in vitro studies. We separated cells using platelet endothelial cell adhesion molecule antibody and characterized ECs with antibodies against intercellular adhesion molecule-1, acetylated-low density lipoprotein, and vascular endothelial (VE)-cadherin. Further, we confirmed microvascular origin of these cells using Griffonia simplicifolia and Helix pomatia (negative control) staining. Barrier properties of EC monolayer were characterized by conducting electric cell-substrate impedance sensing experiments with the edemagenic agents, lipopolysaccharide and nocodazole, and known barrier-protective agents, adenosine and sphingosine-1-phosphate. The described complete protocol provided consistent and reproducible results.

New therapeutic approach to heart failure due to myocardial infarction based on targeting growth hormone-releasing hormone receptor

Background

We previously showed that growth hormone-releasing hormone (GHRH) agonists are cardioprotective following myocardial infarction (MI). Here, our aim was to evaluate the in vitro and in vivo activities of highly potent new GHRH agonists, and elucidate their mechanisms of action in promoting cardiac repair.

Methods and Results

H9c2 cells were cultured in serum-free medium, mimicking nutritional deprivation. GHRH agonists decreased calcium influx and significantly improved cell survival. Rats with cardiac infarction were treated with GHRH agonists or placebo for four weeks. MI size was reduced by selected GHRH agonists (JI-38, MR-356, MR-409); this accompanied an increased number of cardiac c-kit⁺ cells, cellular mitotic divisions, and vascular density. One week post-MI, MR-409 significantly reduced plasma levels of IL-2, IL-6, IL-10 and TNF-α compared to placebo. Gene expression studies revealed favorable outcomes of MR-409 treatment partially result from inhibitory activity on pro-apoptotic molecules and pro-fibrotic systems, and by elevation of bone morphogenetic proteins.

Conclusions

Treatment with GHRH agonists appears to reduce the inflammatory responses post-MI and may consequently improve mechanisms of healing and cardiac remod eling by regulating pathways involved in fibrosis, apoptosis and cardiac repair. Patients with cardiac dysfunction could benefit from treatment with novel GHRH agonists.

Beneficial effects of growth hormone-releasing hormone agonists on rat INS-1 cells and on streptozotocin-induced NOD/SCID mice

Agonists of growth hormone-releasing hormone (GHRH) have been previously reported to promote growth, function, and engraftment of islet cells following transplantation. Here we evaluated recently synthesized GHRH agonists on the proliferation and biological functions of rat pancreatic β-cell line (INS-1) and islets. In vitro treatment of INS-1 cells with GHRH agonists increased cell proliferation, the expression of cellular insulin, insulin-like growth factor-1 (IGF1), and GHRH receptor, and also stimulated insulin secretion in response to glucose challenge. Exposure of INS-1 cells to GHRH agonists, MR-356 and MR-409, induced activation of ERK and AKT pathways. Agonist MR-409 also significantly increased the levels of cellular cAMP and the phosphorylation of cAMP response element binding protein (CREB) in INS-1 cells. Treatment of rat islets with agonist, MR-409 significantly increased cell proliferation, islet size, and the expression of insulin. In vivo daily s.c. administration of 10 μg MR-409 for 3 wk dramatically reduced the severity of streptozotocin (STZ)-induced diabetes in nonobese diabetic severe combined immunodeficiency (NOD/SCID) mice. The maximal therapeutic benefits with respect to the efficiency of engraftment, ability to reach normoglycemia, gain in body weight, response to high glucose challenge, and induction of higher levels of serum insulin and IGF1 were observed when diabetic mice were transplanted with rat islets preconditioned with GHRH agonist, MR-409, and received additional treatment with MR-409 posttransplantation. This study provides an improved approach to the therapeutic use of GHRH agonists in the treatment of diabetes mellitus.

The Acute Respiratory Distress Syndrome: Mechanisms and Perspective Therapeutic Approaches

Acute Respiratory Distress Syndrome (ARDS) is a severe lung inflammatory disorder with a 30-50% mortality. Sepsis and pneumonia are the leading causes of ARDS. On the cellular level there is pulmonary capillary endothelial cell permeability and fluid leakage into the pulmonary parenchyma, followed by neutrophils, cytokines and an acute inflammatory response. When fluid increases in the interstitium then the outward movement continues and protein rich fluid floods the alveolar spaces through the tight junctions of the epithelial cells. Neutrophils play an important role in the development of pulmonary edema associated with acute lung injury or ARDS. Animal studies have shown that endothelial injury appears within minutes to hours after Acute Lung Injury (ALI) initiation with resulting intercellular gaps of the endothelial cells. The Endothelial Cell (EC) gaps allow for permeability of fluid, neutrophils and cytokines into the pulmonary parenchymal space. The neutrophils that infiltrate the lungs and migrate into the airways express pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and contribute to both the endothelial and epithelial integrity disruption of the barriers. Pharmacological treatments have been ineffective. The ARDS Network trial identified low tidal volume mechanical ventilation, positive end expiratory pressure and fluid management guidelines that have improved outcomes for patients with ARDS. Extracorporeal membrane oxygenation is used in specialized centers for severe cases. Prone positioning has recently proven to have significantly decreased ventilator days and days in the intensive care unit. Current investigation includes administration of mesenchymal stem cell therapy, partial fluid ventilation, TIP peptide nebulized administration and the continued examination of pharmacologic drugs.

Severe Ebola virus disease with vascular leakage and multiorgan failure: treatment of a patient in intensive care

BACKGROUND

In the current epidemic of Ebola virus disease in western Africa, many aid workers have become infected. Some of these aid workers have been transferred to specialised hospitals in Europe and the USA for intensified treatment, providing the potential for unique insight into the clinical course of Ebola virus disease under optimised supportive measures in isolation units.

METHODS

A 38-year-old male doctor who had contracted an Ebola virus infection in Sierra Leone was airlifted to University Hospital Frankfurt, Germany, on day 5 after disease onset. Within 72 h of admission to the hospital's high-level isolation unit, the patient developed signs of severe multiorgan failure, including lungs, kidneys, and gastrointestinal tract. In addition to clinical parameters, the diagnostic work-up included radiography, ultrasound, pulse contour cardiac output technology, and microbiological and clinical chemistry analyses. Respiratory failure with pulmonary oedema and biophysical evidence of vascular leak syndrome needed mechanical ventilation. The patient received a 3 day treatment course with FX06 (MChE-F4Pharma, Vienna, Austria), a fibrin-derived peptide under clinical development for vascular leak syndrome. After FX06 administration and concurrent detection of Ebola-virus-specific antibodies and a fall in viral load, vascular leak syndrome and respiratory parameters substantially improved. We gave broad-spectrum empiric antimicrobial therapy and the patient needed intermittent renal replacement therapy. The patient fully recovered.

FINDINGS

This case report shows the feasibility of delivery of successful intensive care therapy to patients with Ebola virus disease under biosafety level 4 conditions.

INTERPRETATION

The effective treatment of vascular leakage and multiorgan failure by combination of ventilatory support, antibiotic treatment, and renal replacement therapy can sustain a patient with severe Ebola virus disease until virological remission. FX06 could potentially be a valuable agent in contribution to supportive therapy.

FUNDING

University Hospital of Frankfurt.

Antagonistic analogs of growth hormone-releasing hormone increase the efficacy of treatment of triple negative breast cancer in nude mice with doxorubicin; A preclinical study

Introduction

This study evaluated the effects of an antagonistic analog of growth hormone-releasing hormone, MIA-602, on tumor growth, response to doxorubicin, expression of drug resistance genes, and efflux pump function in human triple negative breast cancers.

Methods

HCC1806 (doxorubicin-sensitive) and MX-1 (doxorubicin-resistant), cell lines were xenografted into nude mice and treated with MIA-602, doxorubicin, or their combination. Tumors were evaluated for changes in volume and the expression of the drug resistance genes MDR1 and NANOG. In-vitro cell culture assays were used to analyze the effect of MIA-602 on efflux pump function.

Results

Therapy with MIA-602 significantly reduced tumor growth and enhanced the efficacy of doxorubicin in both cell lines. Control HCC1806 tumors grew by 435%, while the volume of tumors treated with MIA-602 enlarged by 172.2% and with doxorubicin by 201.6%. Treatment with the combination of MIA-602 and doxorubicin resulted in an increase in volume of only 76.2%. Control MX-1 tumors grew by 907%, while tumors treated with MIA-602 enlarged by 434.8% and with doxorubicin by 815%. The combination of MIA-602 and doxorubicin reduced the increase in tumor volume to 256%. Treatment with MIA-602 lowered the level of growth hormone-releasing hormone and growth hormone-releasing hormone receptors and significantly reduced the expression of multidrug resistance (MDR1) gene and the drug resistance regulator NANOG. MIA-602 also suppressed efflux pump function in both cell lines.

Conclusions

We conclude that treatment of triple negative breast cancers with growth hormone-releasing hormone antagonists reduces tumor growth and potentiates the effects of cytotoxic therapy by nullifying drug resistance.