The inflammatory response to cell death

Mechanosensing dysregulation in the fibroblast: A hallmark of the aging heart

The myofibroblast is a specialized fibroblast that expresses α-smooth muscle actin (α-SMA) and participates in wound contraction and fibrosis. The fibroblast to myofibroblast transition depends on chemical and mechanical signals. A fibroblast senses the changes in the environment (extracellular matrix (ECM)) and transduces these changes to the cytoskeleton and the nucleus, resulting in activation or inhibition of α-SMA transcription in a process called mechanosensing. A stiff matrix greatly facilitates the transition from fibroblast to myofibroblast, and although the aging heart is much stiffer than the young one, the aging fibroblast has difficulties in transitioning into the contractile phenotype. This suggests that the events occurring downstream of the matrix, such as activation or changes in expression levels of various proteins participating in mechanotransduction can negatively alter the ability of the aging fibroblast to become a myofibroblast. In this review, we will discuss in detail the changes in ECM, receptors (integrin or non-integrin), focal adhesions, cytoskeleton, and transcription factors involved in mechanosensing that occur with aging.

Autologous thrombin preparations: Biocompatibility and growth factor release

Platelet-rich plasma (PRP) has been investigated to promote wound healing in a variety of tissues. Thrombin, another essential component of wound healing, is sometimes combined with PRP to generate a fibrin clot in order to retain the sample at the delivery site and to stimulate growth factor release. Using a fully autologous approach, autologous serum (AS) with thrombin activity can be prepared using a one-step procedure by supplementing with ethanol (E⁺ AS) to prolong room temperature stability or prepared ethanol free (E^- AS) by utilizing a two-step procedure to prolong stability. The objective of this study was to evaluate potential wound healing mechanisms of these two preparations using commercially available devices. A variety of tests were conducted to assess biocompatibility and growth factor release from PRP at various ratios. It was found that E^- AS contained greater leukocyte viability in the product (97.1 ± 2.0% compared to 41.8 ± 11.5%), supported greater bone marrow mesenchymal stem cell proliferation (3.7× vs 0.8× at a 1:4 ratio and 3.6× vs 1.6× at a 1:10 ratio), and stimulated release of growth factors and cytokines from PRP to a greater extent than E⁺ AS. Of the 36 growth factors and cytokines evaluated, release of 27 of them were significantly reduced by the presence of ethanol in at least one of the tested configurations. It is concluded that the high concentrations of ethanol needed to stabilize point of care autologous thrombin preparations could be detrimental to normal wound healing processes.

Treadmill exercise attenuates cerebral ischaemic injury in rats by protecting mitochondrial function via enhancement of caveolin-1

AIMS

Exercise training has a neuroprotective effect against ischaemic injury, but the underlying mechanism is not completely clear. This study explored the potential mechanisms underlying the protective effects of treadmill training and caveolin-1 regulation against mitochondrial dysfunction in cerebral ischaemic injury.

MAIN METHODS

After middle cerebral artery occlusion (MCAO) surgery, rats were subjected to treadmill training and received daidzein injections and combined therapy. A series of analyses, including neurological function scoring; body weight measurement; Nissl, haematoxylin and eosin staining; cerebral infarction volume assessment; mitochondrial morphology examination; caveolin-1, cytoplasmic and mitochondrial cytochrome C (CytC), and translocase of outer membrane 20 (TOM20) expression analysis; apoptosis index analysis; and transmission electron microscopy were conducted.

KEY FINDINGS

Treadmill training increased caveolin-1 expression, reduced neurobehavioral scores and cerebral infarction volumes, improved tissue morphology, reduced neuronal loss, inhibited mitochondrial outer membrane permeabilization (MOMP) through the caveolin-1 pathway, prevented excessive Cyt-C release from mitochondria, and reduced the degrees of apoptosis and mitochondrial damage. In addition, treadmill training increased the expression of TOM20 through the caveolin-1 pathway and maintained import signal function, thereby protecting mitochondrial integrity.

SIGNIFICANCE

Treadmill exercise protected mitochondrial integrity and inhibited the endogenous mitochondrial apoptosis pathway. The damage of cerebral ischaemia was alleviated in rats through enhancement of caveolin-1 by treadmill exercise.

Ionizing radiation-induced risks to the central nervous system and countermeasures in cellular and rodent models

PURPOSE

Harmful effects of ionizing radiation on the Central Nervous System (CNS) are a concerning outcome in the field of cancer radiotherapy and form a major risk for deep space exploration. Both acute and chronic CNS irradiation induce a complex network of molecular and cellular alterations including DNA damage, oxidative stress, cell death and systemic inflammation, leading to changes in neuronal structure and synaptic plasticity with behavioral and cognitive consequences in animal models. Due to this complexity, countermeasure or therapeutic approaches to reduce the harmful effects of ionizing radiation include a wide range of protective and mitigative strategies, which merit a thorough comparative analysis.

MATERIALS AND METHODS

We reviewed current approaches for developing countermeasures to both targeted and non-targeted effects of ionizing radiation on the CNS from the molecular and cellular to the behavioral level.

RESULTS

We focus on countermeasures that aim to mitigate the four main detrimental actions of radiation on CNS: DNA damage, free radical formation and oxidative stress, cell death, and harmful systemic responses including tissue death and neuroinflammation. We propose a comprehensive review of CNS radiation countermeasures reported for the full range of irradiation types (photons and particles, low and high linear energy transfer) and doses (from a fraction of gray to several tens of gray, fractionated and unfractionated), with a particular interest for exposure conditions relevant to deep-space environment and radiotherapy. Our review reveals the importance of combined strategies that increase DNA protection and repair, reduce free radical formation and increase their elimination, limit inflammation and improve cell viability, limit tissue damage and increase repair and plasticity.

CONCLUSIONS

The majority of therapeutic approaches to protect the CNS from ionizing radiation have been limited to acute high dose and high dose rate gamma irradiation, and few are translatable from animal models to potential human application due to harmful side effects and lack of blood-brain barrier permeability that precludes peripheral administration. Therefore, a promising research direction would be to focus on practical applicability and effectiveness in a wider range of irradiation paradigms, from fractionated therapeutic to deep space radiation. In addition to discovering novel therapeutics, it would be worth maximizing the benefits and reducing side effects of those that already exist. Finally, we suggest that novel cellular and tissue models for developing and testing countermeasures in the context of other impairments might also be applied to the field of CNS responses to ionizing radiation.

Electronic Nicotine Delivery System Aerosol-induced Cell Death and Dysfunction in Macrophages and Lung Epithelial Cells

Electronic nicotine delivery system (ENDS) use is outpacing our understanding of its potential harmful effects. Homeostasis of the lung is maintained through proper balance of cell death, efferocytic clearance, and phagocytosis of pathogens. To investigate whether ENDS use has the potential to alter this balance, we developed physiologically relevant ENDS exposure paradigms for lung epithelial cells and primary macrophages. In our studies, cells were exposed directly to aerosol made from carefully controlled components with and without nicotine. We found that ENDS aerosol exposure led to apoptosis, secondary necrosis, and necrosis in lung epithelial cell models. In contrast, macrophages died mostly by apoptosis and inflammatory caspase-mediated cell death when exposed to ENDS aerosol. The clearance of dead cells and pathogens by efferocytosis and phagocytosis, respectively, is an important process in maintaining a healthy lung. To investigate the impact of ENDS aerosol on macrophage function independent of general toxicity, we used an exposure time that did not induce cell death in primary macrophages. Exposure to ENDS aerosol containing nicotine inhibited nearly all phagocytic and greatly reduced the efferocytic abilities of primary macrophages. When challenged with a bacterial pathogen, there was decreased bacterial clearance. The presence of nicotine in the ENDS aerosol increased its toxicity and functional impact; however, nicotine exposure alone did not have any deleterious effects. These data demonstrate that ENDS aerosol exposure could lead to increased epithelial cell and macrophage death in the lung and impair important macrophage functions that are essential for maintenance of lung function.

Fruticuline A, a chemically-defined diterpene, exerts antineoplastic effects in vitro and in vivo by multiple mechanisms

Natural products have been recognized as important bioactive compounds on the basis of their wide biological properties. Here we investigated the antitumor effect and molecular mechanisms of the diterpene Fruticuline A (fruti) from Salvia lachnostachys, in human cancer cell lineages and Solid Ehrlich Carcinoma in mice. Fruti reduced MCF-7 and HepG2 proliferation by the reduction of Cyclin D1 levels and decreased NF-κB gene levels in both cell types. Furthermore, fruti also induced apoptosis in HepG2 cells, reduced Bcl-2 gene expression and induced necroptosis by increasing Ripk in MCF-7 cells. In mice, fruti prevented tumor development and reduced Cyclin D1, Bcl-2 and Rela gene levels, and reduced the p-NF-κB/NF-κB ratio in tumor tissue. Furthermore, fruti induced necrosis and apoptosis, increased N-acetyl-β-D-glucosaminidase and TNF-α levels and reduced IL-10 and Vegf levels in tumor tissue. Collectively, fruti exerts antitumor effects through the inhibition of the NF-κB pathway, reducing Cyclin D1 and Bcl-2 levels. In vitro the apoptosis and necroptosis pathways are involved in the cellular death, whereas in vivo, cells undergo necrosis by increased tumor inflammation and reduction of angiogenesis. Thus, fruticuline A acts in tumor cells by multiple mechanisms and represents a promising molecule for drug development in cancer treatment.

Incorporation of Reversible Electroporation Into Electrolysis Accelerates Apoptosis for Rat Liver Tissue

Tissue electrolysis is an alternative modality that uses a low intensity direct electric current passing through at least 2 electrodes within the tissue and resulting electrochemical products including chlorine and hydrogen. These products induce changes in pH around electrodes and cause dehydration resulting from electroosmotic pressure, leading to changes in microenvironment and thus metabolism of the tissues, yielding apoptosis. The procedure requires adequate time for electrochemical reactions to yield products sufficient to induce apoptosis of the tissues. Incorporation of electroporation into electrolysis can decrease the treatment time and enhance the efficiency of electrolytic ablation. Electroporation causes permeabilization in the cell membrane allowing the efflux of potassium ions and extension of the electrochemical area, facilitating the electrolysis process. However, little is known about the combined effects on apoptosis in liver ablation. In this study, we performed an immunohistochemical evaluation of apoptosis for the incorporation of electroporation into electrolysis in liver tissues. To do so, the study was performed with microelectrodes for fixed treatment time while the applied voltage varied to increase the applied total energy for electrolysis. The apoptotic rate for electrolytic ablation increased with enhanced applied energy. The apoptotic rate was 4.31 ± 1.73 times that of control in the synergistic combination compared to 1.49 ± 0.33 times that of the control in electrolytic ablation alone. Additionally, tissue structure was better preserved in synergistic combination ablation compared to electrolysis with an increment of 3.8 mA. Thus, synergistic ablation may accelerate apoptosis and be a promising modality for the treatment of liver tumors.

Alumina Ceramic Exacerbates the Inflammatory Disease by Activation of Macrophages and T Cells

(1) Background: Aluminum oxide (Al₂O₃) ceramic is one of the materials used for artificial joints, and it has been known that their fine particles (FPs) are provided by the wear of the ceramic. Al₂O₃ FPs have been shown to induce macrophage activation in vitro; however, the inflammatory effect in vivo has not been studied. (2) Methods: We examined the in vivo effect of Al₂O₃ FPs on the innate and adaptive immune cells in the mice. (3) Results: Al₂O₃ FPs promoted the activation of spleen macrophages; however, conventional dendritic cells (cDCs), plasmacytoid DCs (pDCs), and natural killer (NK) cells were not activated. In addition, increases in the CD4 and CD8 T cells was induced in the spleens of the mice treated with Al₂O₃ FPs, which differentiated into interferon-gamma (IFN-γ)-producing helper T1 (Th1) and cytotoxic T1 (Tc1) cells. Finally, the injection of Al₂O₃ FPs exacerbated dextran sulfate sodium (DSS)-induced inflammation in the colon, mediated by activated and increased number of CD4 and CD8 T cells. (4) Conclusions: These data demonstrate that FPs of Al₂O₃ ceramic may contribute to the exacerbation of inflammatory diseases in the patients.

Halodule pinifolia (Seagrass) attenuated lipopolysaccharide-, carrageenan-, and crystal-induced secretion of pro-inflammatory cytokines: mechanism and chemistry

OBJECTIVES

The study aimed to explore the anti-inflammatory effect, underlying mechanism, and chemistry of Halodule pinifolia extract.

METHODS

The ethyl acetate (EHP) and methanol (MHP) extracts of Halodule pinifolia were screened for pro-inflammatory cytokine inhibition effect under various in vitro (LPSand crystal-induced inflammation) and in vivo models (LPS-induced endotoxaemia model, carrageenan-induced paw oedema model, and oxalate-induced renal nephropathy model of inflammation). The effect of EHP on the expression of inflammatory markers using western blot analysis (in vitro) was investigated. Chemical constituents of bioactive EHP were isolated through chromatography and characterised using NMR spectroscopy. Furthermore, EHP was standardised for rosmarinic acid, vanillic acid, and ethyl protocatechuate using HPLC. Also, total phytosterols, phenolic, and flavonoid content of EHP were determined by UV spectroscopy.

KEY FINDINGS

EHP was comparatively more effective than MHP in inhibiting cytokines secretions under LPS-induced in vitro models. Furthermore, EHP was screened under endotoxaemia in vivo model, EHP (250 mg/kg) reduced plasma IL-6, TNF-α, and IL-1β levels by 88.3%, 78.2%, and 74.5%, respectively. In the carrageenan-induced oedema model, EHP (200 mg/kg) reduced paw volume and release of TNF-α (69.3%) and IL-1β (43.1%). EHP (200 mg/kg) further controlled renal nephropathy by inhibiting plasma IL-1β and BUN levels. Also, a significant reduction of mRNA expressions of TNF-α and IL-1β and KIM-1 in renal tissues was observed. Through western blot, EHP was identified to regulate the expression of pro-form as well as mature-form of IL-1β and caspase-1. EHP constituted rosmarinic acid (RA), vanillic acid (VA), ethyl protocatechuate (EP), sitosterol, stigmasterol, campesterol, and dihydrobrassicasterol. It was determined that 4.6 mg/g of RA, 2.92 mg/g of VA, 0.76 mg/g of EP, 21.7 mg/g of total phenolics, 29.8 mg/g of total flavonoids, and 48.2 mg/g of total phytosterols were present in dry EHP. The presence of anti-inflammatory constituents such as RA, VA, and PE in EHP corroborated the in vitro and in vivo anti-inflammatory activity of EHP.

CONCLUSION

The anti-inflammatory property of EHP and its action through attenuation of pan-cytokines suggest that it can be developed into an oral pharmaceutical drug.

Immunometabolic function of the transcription cofactor VGLL3 provides an evolutionary rationale for sexual dimorphism in autoimmunity

Sexual dimorphism is exhibited remarkably in the female predominance of autoimmune diseases (e.g. systemic lupus erythematosus, female-to-male ratio 9 : 1). To understand the female bias in autoimmunity, we focused on vestigial-like family member 3 (VGLL3), a molecule with increased expression in females and known to promote autoimmunity. We report that VGLL3 mediates the cellular stress response by upregulating p53 and IL-17C. Energy stress allows VGLL3 to be induced by IFNα, which ultimately leads to p53-dependent, lupus-associated, inflammatory cell death. Our results suggest that female-biased expression of VGLL3 helps cells adapt to metabolic stress, which, intriguingly, is known as a significant challenge during the evolution of placental mammals due to the need to feed a developing embryo. The findings also uncover the importance of maintaining metabolic homeostasis in the prevention of autoimmunity.

Emerging connectivity of programmed cell death pathways and its physiological implications

The removal of functionally dispensable, infected or potentially neoplastic cells is driven by programmed cell death (PCD) pathways, highlighting their important roles in homeostasis, host defence against pathogens, cancer and a range of other pathologies. Several types of PCD pathways have been described, including apoptosis, necroptosis and pyroptosis; they employ distinct molecular and cellular processes and differ in their outcomes, such as the capacity to trigger inflammatory responses. Recent genetic and biochemical studies have revealed remarkable flexibility in the use of these PCD pathways and indicate a considerable degree of plasticity in their molecular regulation; for example, despite having a primary role in inducing pyroptosis, inflammatory caspases can also induce apoptosis, and conversely, apoptotic stimuli can trigger pyroptosis. Intriguingly, this flexibility is most pronounced in cellular responses to infection, while apoptosis is the dominant cell death process through which organisms prevent the development of cancer. In this Review, we summarize the mechanisms of the different types of PCD and describe the physiological and pathological processes that engage crosstalk between these pathways, focusing on infections and cancer. We discuss the intriguing notion that the different types of PCD could be seen as a single, coordinated cell death system, in which the individual pathways are highly interconnected and can flexibly compensate for one another.

Tracing the In Vivo Fate of Nanoparticles with a "Non-Self" Biological Identity

Nanoparticles can acquire a biomolecular corona with a species-specific biological identity. However, "non-self" incompatibility of recipient biological systems is often not considered, for example, when rodents are used as a model organism for preclinical studies of biomolecule-inspired nanomedicines. Using zebrafish embryos as an emerging model for nanobioimaging, here we unravel the in vivo fate of intravenously injected 70 nm SiO₂ nanoparticles with a protein corona preformed from fetal bovine serum (FBS), representing a non-self biological identity. Strikingly rapid sequestration and endolysosomal acidification of nanoparticles with the preformed FBS corona were observed in scavenger endothelial cells within minutes after injection. This led to loss of blood vessel integrity and to inflammatory activation of macrophages over the course of several hours. As unmodified nanoparticles or the equivalent dose of FBS proteins alone failed to induce the observed pathophysiology, this signifies how the corona enriched with a differential repertoire of proteins can determine the fate of the nanoparticles in vivo. Our findings thus reveal the adverse outcome triggered by incompatible protein coronas and indicate a potential pitfall in the use of mismatched species combinations during nanomedicine development.

Photodynamic therapy effect of morpholinium containing silicon (IV) phthalocyanine on HCT-116 cells

In this study, we investigated the in vitro potential of axially 1-morpholiniumpropan-2-ol disubstituted silicon (IV) phthalocyanine (SiPc) which was synthesized previously, on HCT-116 cells as a photodynamic therapy (PDT) agent. The singlet oxygen and photodegradation quantum yields of SiPc were calculated using UV-vis spectrophotometer. The cytotoxic and phototoxic effects of SiPc were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay. Annexin V-FITC/PI double staining kit, cell cycle kit, and mitochondria membrane potential (ΔΨm) assay kit with JC-1 were used to indicate the cell death pathway. Caspase-3 and β-catenin protein expressions were evaluated by western blotting. The singlet oxygen and photodegradation quantum yields of SiPc were calculated as 0.73 and 3.64 × 10^-4 in DMSO. The cell viability assays showed that IC₅₀ value of SiPc did not reach to 100 μM without irradiation. However, excellent phototoxicity was observed in the presence of SiPc upon light irradiation. The cells undergoing early/late apoptosis significantly increased in the presence SiPc at 5 μM upon light irradiation. Besides, the proportion of cells at S and G2/M phase increased. Moreover, mitochondria membrane potentials significantly decreased at 1 and 5 μM of SiPc with light irradiation. While caspase-3 expression increased, β-catenin expression significantly decreased on HCT-116 in the presence of SiPc (p < 0.01). The results indicated that the PDT could be related to apoptosis and Wnt/β-catenin signaling pathway. Based on our findings, SiPc exhibited a significant PDT effect on HCT-116 cells therefore, worthy of more detailed study.

Application of double network of gellan gum and pullulan for bone marrow stem cells differentiation towards chondrogenesis by controlling viscous substrates

Hydrogels have a large amount of water that provides a cartilage-like environment and is used in tissue engineering with biocompatibility and adequate degradation rates. In order to differentiate stem cells, it is necessary to adjust the characteristics of the matrix such as stiffness, stress-relaxing time, and microenvironment. Double network (DN) hydrogels provide differences in cellular biological behavior and have interpenetrating networks that combine the advantages of the components. In this study, by varying the viscous substrate of pullulan (PL), the DN hydrogels of gellan gum (GG) and PL were prepared to determine the cartilage differentiation of bone marrow stem cell (BMSC). The characteristics of GG/PL hydrogel were investigated by examining the swelling ratio, weight loss, sol fraction, compressive modulus, and gelation temperature. The viability, proliferation, and toxicity of BMSCs encapsulated in hydrogels were evaluated. Cartilage phenotype and cartilage differentiation were confirmed by morphology, GAG content, and cartilage-specific gene expression. Overall results demonstrate that GG/PL hydrogels can form cartilage differentiation of BMSCs and can be applied for tissue engineering purposes.

Formation of lamellar body-like structure may be an initiator of didecyldimethylammonium chloride-induced toxic response

Due to the pandemic of coronavirus disease 2019, the use of disinfectants is rapidly increasing worldwide. Didecyldimethylammonium chloride (DDAC) is an EPA-registered disinfectant, it was also a component in humidifier disinfectants that had caused idiopathic pulmonary diseases in Korea. In this study, we identified the possible pulmonary toxic response and mechanism using human bronchial epithelial (BEAS-2B) cells and mice. First, cell viability decreased sharply at a 4 μg/mL of concentration. The volume of intracellular organelles and the ROS level reduced, leading to the formation of apoptotic bodies and an increase of the LDH release. Secretion of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and matrix metalloproteinase-1 also significantly increased. More importantly, lamellar body-like structures were formed in both the cells and mice exposed to DDAC, and the expression of both the indicator proteins for lamellar body (ABCA3 and Rab11a) and surfactant proteins (A, B, and D) was clearly enhanced. In addition, chronic fibrotic pulmonary lesions were notably observed in mice instilled twice (weekly) with DDAC (500 μg), ultimately resulting in death. Taken together, we suggest that disruption of pulmonary surfactant homeostasis may contribute to DDAC-induced cell death and subsequent pathophysiology and that the formation of lamellar body-like structures may play a role as the trigger. In addition, we propose that the cause of sudden death of mice exposed to DDAC should be clearly elucidated for the safe application of DDAC.

Necroptosis in Immuno-Oncology and Cancer Immunotherapy

Immune-checkpoint blockers (ICBs) have revolutionized oncology and firmly established the subfield of immuno-oncology. Despite this renaissance, a subset of cancer patients remain unresponsive to ICBs due to widespread immuno-resistance. To "break" cancer cell-driven immuno-resistance, researchers have long floated the idea of therapeutically facilitating the immunogenicity of cancer cells by disrupting tumor-associated immuno-tolerance via conventional anticancer therapies. It is well appreciated that anticancer therapies causing immunogenic or inflammatory cell death are best positioned to productively activate anticancer immunity. A large proportion of studies have emphasized the importance of immunogenic apoptosis (i.e., immunogenic cell death or ICD); yet, it has also emerged that necroptosis, a programmed necrotic cell death pathway, can also be immunogenic. Emergence of a proficient immune profile for necroptosis has important implications for cancer because resistance to apoptosis is one of the major hallmarks of tumors. Putative immunogenic or inflammatory characteristics driven by necroptosis can be of great impact in immuno-oncology. However, as is typical for a highly complex and multi-factorial disease like cancer, a clear cause versus consensus relationship on the immunobiology of necroptosis in cancer cells has been tough to establish. In this review, we discuss the various aspects of necroptosis immunobiology with specific focus on immuno-oncology and cancer immunotherapy.

Tandem-Mass-Tag Based Proteomic Analysis Facilitates Analyzing Critical Factors of Porous Silicon Nanoparticles in Determining Their Biological Responses under Diseased Condition

The analysis of nanoparticles' biocompatibility and immunogenicity is mostly performed under a healthy condition. However, more clinically relevant evaluation conducted under pathological condition is less known. Here, the immunogenicity and bio-nano interactions of porous silicon nanoparticles (PSi NPs) are evaluated in an acute liver inflammation mice model. Interestingly, a new mechanism in which PSi NPs can remit the hepatocellular damage and inflammation activation in a surface dependent manner through protein corona formation, which perturbs the inflammation by capturing the pro-inflammatory signaling proteins that are inordinately excreted or exposed under pathological condition, is found. This signal sequestration further attenuates the nuclear factor κB pathway activation and cytokines production from macrophages. Hence, the study proposes a potential mechanism for elucidating the altered immunogenicity of nanomaterials under pathological conditions, which might further offer insights to establish harmonized standards for assessing the biosafety of biomaterials in a disease-specific or personalized manner.

Damage-associated molecular patterns in trauma

In 1994, the "danger model" argued that adaptive immune responses are driven rather by molecules released upon tissue damage than by the recognition of "strange" molecules. Thus, an alternative to the "self versus non-self recognition model" has been provided. The model, which suggests that the immune system discriminates dangerous from safe molecules, has established the basis for the future designation of damage-associated molecular patterns (DAMPs), a term that was coined by Walter G. Land, Seong, and Matzinger. The pathological importance of DAMPs is barely somewhere else evident as in the posttraumatic or post-surgical inflammation and regeneration. Since DAMPs have been identified to trigger specific immune responses and inflammation, which is not necessarily detrimental but also regenerative, it still remains difficult to describe their "friend or foe" role in the posttraumatic immunogenicity and healing process. DAMPs can be used as biomarkers to indicate and/or to monitor a disease or injury severity, but they also may serve as clinically applicable parameters for optimized indication of the timing for, i.e., secondary surgeries. While experimental studies allow the detection of these biomarkers on different levels including cellular, tissue, and circulatory milieu, this is not always easily transferable to the human situation. Thus, in this review, we focus on the recent literature dealing with the pathophysiological importance of DAMPs after traumatic injury. Since dysregulated inflammation in traumatized patients always implies disturbed resolution of inflammation, so-called model of suppressing/inhibiting inducible DAMPs (SAMPs) will be very briefly introduced. Thus, an update on this topic in the field of trauma will be provided.

Estrogen exacerbates mammary involution through neutrophil-dependent and -independent mechanism

There is strong evidence that the pro-inflammatory microenvironment during post-partum mammary involution promotes parity-associated breast cancer. Estrogen exposure during mammary involution drives tumor growth through neutrophils’ activity. However, how estrogen and neutrophils influence mammary involution are unknown. Combined analysis of transcriptomic, protein, and immunohistochemical data in BALB/c mice showed that estrogen promotes involution by exacerbating inflammation, cell death and adipocytes repopulation. Remarkably, 88% of estrogen-regulated genes in mammary tissue were mediated through neutrophils, which were recruited through estrogen-induced CXCR2 signalling in an autocrine fashion. While neutrophils mediate estrogen-induced inflammation and adipocytes repopulation, estrogen-induced mammary cell death was via lysosome-mediated programmed cell death through upregulation of cathepsin B, Tnf and Bid in a neutrophil-independent manner. Notably, these multifaceted effects of estrogen are mostly mediated by ERα and unique to the phase of mammary involution. These findings are important for the development of intervention strategies for parity-associated breast cancer.

Mutations in COMP cause familial carpal tunnel syndrome

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome, affecting a large proportion of the general population. Genetic susceptibility has been implicated in CTS, but the causative genes remain elusive. Here, we report the identification of two mutations in cartilage oligomeric matrix protein (COMP) that segregate with CTS in two large families with or without multiple epiphyseal dysplasia (MED). Both mutations impair the secretion of COMP by tenocytes, but the mutation associated with MED also perturbs its secretion in chondrocytes. Further functional characterization of the CTS-specific mutation reveals similar histological and molecular changes of tendons/ligaments in patients’ biopsies and the mouse models. The mutant COMP fails to oligomerize properly and is trapped in the ER, resulting in ER stress-induced unfolded protein response and cell death, leading to inflammation, progressive fibrosis and cell composition change in tendons/ligaments. The extracellular matrix (ECM) organization is also altered. Our studies uncover a previously unrecognized mechanism in CTS pathogenesis.

Familial carpal tunnel syndrome (CTS) is common, but causal genes are not characterized. Here the authors report two CTS-related mutations in two large families that impair secretion of COMP in tenocytes, leading to ER stress-induced unfolded protein response, inflammation and fibrosis in patients and mouse models.

Targeting Bacterial Antioxidant Systems for Antibiotics Development

The emergence of multidrug-resistant bacteria has become an urgent issue in modern medicine which requires novel strategies to develop antibiotics. Recent studies have supported the hypothesis that antibiotic-induced bacterial cell death is mediated by Reactive Oxygen Species (ROS). The hypothesis also highlighted the importance of antioxidant systems, the defense mechanism which contributes to antibiotic resistance. Thioredoxin and glutathione systems are the two major thiol-dependent systems which not only provide antioxidant capacity but also participate in various biological events in bacteria, such as DNA synthesis and protein folding. The biological importance makes them promising targets for novel antibiotics development. Based on the idea, ebselen and auranofin, two bacterial thioredoxin reductase inhibitors, have been found to inhibit the growth of bacteria lacking the GSH efficiently. A recent study combining ebselen and silver exhibited a strong synergistic effect against Multidrug-Resistant (MDR) Gram-negative bacteria which possess both thioredoxin and glutathione systems. These drug-repurposing studies are promising for quick clinical usage due to their well-known profile.

Dysregulation of Cell Death in Human Chronic Inflammation

Inflammation is a fundamental biological process mediating host defense and wound healing during infections and tissue injury. Perpetuated and excessive inflammation may cause autoinflammation, autoimmunity, degenerative disorders, allergies, and malignancies. Multimodal signaling by tumor necrosis factor receptor 1 (TNFR1) plays a crucial role in determining the transition between inflammation, cell survival, and programmed cell death. Targeting TNF signaling has been proven as an effective therapeutic in several immune-related disorders. Mouse studies have provided critical mechanistic insights into TNFR1 signaling and its potential role in a broad spectrum of diseases. The characterization of patients with monogenic primary immunodeficiencies (PIDs) has highlighted the importance of TNFR1 signaling in human disease. In particular, patients with PIDs have revealed paradoxical connections between immunodeficiency, chronic inflammation, and dysregulated cell death. Importantly, studies on PIDs may help to predict beneficial effects and side-effects of therapeutic targeting of TNFR1 signaling.

Multi-Habitat Radiomics Unravels Distinct Phenotypic Subtypes of Glioblastoma with Clinical and Genomic Significance

We aimed to evaluate the potential of radiomics as an imaging biomarker for glioblastoma (GBM) patients and explore the molecular rationale behind radiomics using a radio-genomics approach. A total of 144 primary GBM patients were included in this study (training cohort). Using multi-parametric MR images, radiomics features were extracted from multi-habitats of the tumor. We applied Cox-LASSO algorithm to build a survival prediction model, which we validated using an independent validation cohort. GBM patients were consensus clustered to reveal inherent phenotypic subtypes. GBM patients were successfully stratified by the radiomics risk score, a weighted sum of radiomics features, corroborating the potential of radiomics as a prognostic biomarker. Using consensus clustering, we identified three distinct subtypes which significantly differed in the prognosis ("heterogenous enhancing", "rim-enhancing necrotic", and "cystic" subtypes). Transcriptomic traits enriched in individual subtypes were in accordance with imaging phenotypes summarized by radiomics. For example, rim-enhancing necrotic subtype was well described by radiomics profiling (T2 autocorrelation and flat shape) and highlighted by the inflammatory genomic signatures, which well correlated to its phenotypic peculiarity (necrosis). This study showed that imaging subtypes derived from radiomics successfully recapitulated the genomic underpinnings of GBMs and thereby confirmed the feasibility of radiomics as an imaging biomarker for GBM patients with comprehensible biologic annotation.

Modulation of inflammatory processes by thermal stimulating and RPE regenerative laser therapies in age related macular degeneration mouse models

Purpose

Inflammatory processes play a major role within the multifactorial pathogenesis of age-related macular degeneration (AMD). Neuroretina sparing laser therapies, thermal stimulation of the retina (TSR) and selective retina therapy (SRT), are known to reduce AMD-like pathology in vitro and in vivo. We investigated the effect of TSR and SRT on inflammatory processes in AMD mouse models.

Methods

One randomized eye of 8 months old apolipoprotein (Apo)E and 9 months old nuclear factor (erythroid-derived 2) -like 2 (NRF2) knock out mice were treated by TSR (10 ms, 532 nm, 50 µm² spot size, mean 4.5 W, ~200 spots) or SRT (~1.4 µs pulses, 532 nm, 50 µm spot size, 100 Hz over 300 ms, mean 2.5 µJ per pulse, ~200 spots). Fellow eyes, untreated knock out mice and wild-type BL/6J mice acted as controls. All mice were examined funduscopically and by optical coherence tomography (OCT) at the day of laser treatment. Mice were euthanized and enucleated either 1 day or 7 days after laser treatment and examined by gene expression analysis of 84 inflammatory genes.

Results

The inflammatory gene expression profile of both knock out models compared to healthy BL/6J mice suggests a regulation of pro- and anti-inflammatory processes especially concerning T-cell activity and immune cell recruitment. TSR resulted in downregulation of several pro-inflammatory cell-mediators both in ApoE -/- and NRF2-/- mice compared to treatment naïve litter mates one day after treatment. In contrast, SRT induced pro-inflammatory cell-mediators connected with necrosis one day after treatment as expected following laser-induced selective RPE cell death. Seven days after laser treatment, both findings were reversed.

Conclusions

Both TSR and SRT influence inflammatory processes in AMD mouse models. However, they act conversely. TSR leads to anti-inflammatory processes shortly after laser therapy and induces immune-cell recruitment one week after treatment. SRT leads to a quick inflammatory response to laser induced RPE necrotic processes. One week after SRT inflammation is inhibited. It remains unclear, if and to what extent this might play a role in a therapeutic or preventive approach of both laser modalities on AMD pathology.

Cell Membrane-Based Biomimetic Nanoparticles and the Immune System: Immunomodulatory Interactions to Therapeutic Applications

Nanoparticle-based drug delivery systems have been synthesized from a wide array of materials. The therapeutic success of these platforms hinges upon their ability to favorably interact with the biological environment (both systemically and locally) and recognize the diseased target tissue. The immune system, composed of a highly coordinated organization of cells trained to recognize foreign bodies, represents a key mediator of these interactions. Although components of this system may act as a barrier to nanoparticle (NP) delivery, the immune system can also be exploited to target and trigger signaling cues that facilitate the therapeutic response stemming from systemic administration of NPs. The nano-bio interface represents the key facilitator of this communication exchange, where the surface properties of NPs govern their in vivo fate. Cell membrane-based biomimetic nanoparticles have emerged as one approach to achieve targeted drug delivery by actively engaging and communicating with the biological milieu. In this review, we will highlight the relationship between these biomimetic nanoparticles and the immune system, emphasizing the role of tuning the nano-bio interface in the immunomodulation of diseases. We will also discuss the therapeutic applications of this approach with biomimetic nanoparticles, focusing on specific diseases ranging from cancer to infectious diseases. Lastly, we will provide a critical evaluation on the current state of this field of cell membrane-based biomimetic nanoparticles and its future directions in immune-based therapy.

Methamphetamine induces GSDME-dependent cell death in hippocampal neuronal cells through the endoplasmic reticulum stress pathway

Methamphetamine (METH) is an illegal amphetamine-typed psychostimulant that is abused worldwide and causes serious public health problems. METH exposure induces apoptosis and autophagy in neuronal cells. However, the role of pyroptosis in METH-induced neurotoxicity is still unclear. Here, we investigate whether pyroptosis is involved in METH-induced hippocampal neurotoxicity and the potential mechanisms of Endoplasmic reticulum (ER) stress in hippocampal neuronal cells. For this purpose, the expression levels of pyroptosis-related proteins, GSDMD and GSDME, were analyzed by immunoblotting and immunohistochemistry in the hippocampal neuron cell line HT-22. Next, we explored METH-induced pyroptosis in HT-22 using immunoblotting, LDH assays and SYTOX green acid staining. Further, the relationship between pyroptosis and ER stress in METH-induced hippocampal neuron damage was studied in HT-22 cells using inhibitors including TUDCA, a specific inhibitor of ER stress, GSK-2656157, a PERK pathway inhibitor and STF-0803010, an inhibitor of IRE1α endoribonuclease activity. This relationship was also studied using siRNAs, including siTRAF2, an siRNA against IRE1α kinase activity and siATF6 against the ATF6 pathway, which were analyzed by immunoblotting, LDH assays and SYTOX green acid staining. GSDME but not GSDMD was found to be expressed in HT-22 cells. METH treatment induced the upregulation of cleaved GSDME-NT and LDH release, as well as the increase of SYTOX green positive cells in HT-22 cells, which was partly reversed by inhibitors and siRNAs, indicating that the ER stress signaling pathway was involved in GSDME-dependent cell death induced by METH. In summary, these results revealed that METH induced ER stress that mediated GSDME-dependent cell death in hippocampal neuronal cells. These findings provide novel insight into the mechanisms of METH-induced neurotoxicity.

Cell free DNA biology and its involvement in breast carcinogenesis

Liquid biopsy represents a procedure for minimally invasive analysis of non-solid tissue, blood and other body fluids. It comprises a set of analytes that includes circulating tumor cells (CTCs) and circulating free DNA (cfDNA), RNA, long noncoding RNA (lncRNA) and micro RNA (miRNA), as well as extracellular vesicles. These novel analytes represent an alternative tool to complement diagnosis and monitor and predict response to treatment of the tumoral process and may be used for other disease processes such viral and parasitic infection. This review focuses on the biologic and molecular characteristics of cfDNA in general and the molecular changes (mutational and epigenetic) proven useful in oncologic practice for diagnosis, monitoring and treatment of breast cancer specifically.

Size-Optimized Microspace Culture Facilitates Differentiation of Mouse Induced Pluripotent Stem Cells into Osteoid-Rich Bone Constructs

Microspace culture is promising for self-organization of induced pluripotent stem cells (iPSCs). However, the optimal size of microspaces for osteogenic differentiation is unclear. We hypothesized that a specific microspace size could facilitate self-organizing iPSC differentiation to form bone-like tissue in vitro. The objectives of this study were to investigate such effects of microspace size and to evaluate bone regeneration upon transplantation of the resulting osteogenic constructs. Dissociated mouse gingival fibroblast-derived iPSCs were plated in ultra-low-attachment microspace culture wells containing hundreds of U-bottom-shaped microwell spots per well to form cell aggregates in growth medium. The microwells had different aperture diameters/depths (400/560 μm (Elp400), 500/700 μm (Elp500), and 900/700 μm (Elp900)) (Kuraray; Elplasia). After 5 days of aggregation, cells were maintained in osteogenic induction medium for 35 days. Only cells in the Elp500 condition tightly aggregated and maintained high viability during osteogenic induction. After 10 days of induction, Elp500 cell constructs showed significantly higher gene expression of Runx2, Osterix, Collagen 1a1, Osteocalcin, Bone sialoprotein, and Osteopontin compared to constructs in Elp400 and Elp900. In methylene blue-counterstained von Kossa staining and Movat's pentachrome staining, only Elp500 constructs showed robust osteoid formation on day 35, with high expression of type I collagen (a major osteoid component) and osteocalcin proteins. Cell constructs were transplanted into rat calvarial bone defects, and micro-CT analysis after 3 weeks showed better bone repair with significantly higher bone mineral density in the Elp500 group compared to the Elp900 group. These results suggest that microspace size affects self-organized osteogenic differentiation of iPSCs. Elp500 microspace culture specifically induces mouse iPSCs into osteoid-rich bone-like tissue possessing high bone regeneration capacity.

Glioma stem cell (GSC)-derived autoschizis-like products confer GSC niche properties involving M1-like tumor-associated macrophages

Spontaneous necrosis is a defining feature of glioblastomas (GBMs), the most malignant glioma. Despite its strong correlations with poor prognosis, it remains unclear whether necrosis could be a possible cause or mere consequence of glioma progression. Here we isolated a particular fraction of necrotic products spontaneously arising from glioma cells, morphologically and biochemically defined as autoschizis-like products (ALPs). When administered to granulocyte macrophage colony-stimulating factor (GM-CSF)-primed bone marrow-derived macrophage/dendritic cells (Mφ/DCs), ALPs were found to be specifically engulfed by Mφs expressing a tumor-associated macrophage (TAM) marker CD204. ALPs from glioma stem cells (GSCs) had higher activity for the TAM development than those from non-GSCs. Of note, expression of the Il12b gene encoding a common subunit of IL-12/23 was upregulated in ALPs-educated Mφs. Furthermore, IL-12 protein evidently enhanced the sphere-forming activity of GBM patient-derived cells, although interestingly IL-12 is generally recognized as an antitumoral M1-Mφ marker. Finally, in silico analysis of The Cancer Genome Atlas (TCGA) transcriptome data of primary and recurrent GBMs revealed that higher expression of these IL-12 family genes was well correlated with more infiltration of M1-type TAMs and closely associated with poorer prognosis in recurrent GBMs. Our results highlight a role of necrosis in GSC-driven self-beneficial niche construction and glioma progression, providing important clues for developing new therapeutic strategies against gliomas.

Quantitative alterations in bovine milk proteome from healthy, subclinical and clinical mastitis during S. aureus infection

Bovine mastitis, caused by Staphylococcus aureus, is a major impediment to milk production and lacks markers to indicate disease progression in cows and buffaloes. Thus, the focus of this study was to identify proteins marking the transition from subclinical to clinical mastitis. Whey proteins were isolated from 6 group's i.e. healthy, subclinical and clinical mastitis of Holstein Friesian cow and Murrah buffalo. Mass spectrometry and statistical analysis (ANOVA and t-tests) were performed on 12 biological samples each from cow and buffalo (4 per healthy, subclinical and clinical mastitis) resulting in a total of 24 proteome datasets. Collectively, 1479 proteins were identified of which significant proteins were shortlisted by a combination of fold change (≤ 0.5 or ≥ 2) and q < 0.05. Of these proteins, 128 and 163 indicated disease progression in cow and buffalo, respectively. Change in expression of haptoglobin and fibronectin from Holstein Friesian while spermadhesin and osteopontin from Murrah correlated with disease progression. Similarly, angiogenin and cofilin-1 were upregulated while ubiquitin family members were downregulated during disease transition. Subsequently, selected proteins (e.g. osteopontin and fibrinogen-α) were validated by Western blots. The results of this study provide deeper insights into whey proteome dynamics and signature patterns indicative of disease progression. BIOLOGICAL SIGNIFICANCE: Bovine mastitis is the most lethal infectious disease causing a huge economic loss in the dairy industry. In an attempt, to understand the dynamics of whey proteome in response to S. aureus infection, whey protein collected from healthy, subclinical and clinical mastitic HF and Mu were investigated. A total of 1479 proteins were identified, of which 128 and 163 had signature pattern in each stage indicative of the progression of the disease. The results of the present study provide a foundation to better understand the complexity of mastitis that will ultimately help facilitate early therapeutic and husbandry-based intervention to improve animal health and milk quality.

Cinnamaldehyde Enhanced Functional Recovery after Sciatic Nerve Crush Injury in Rats

Peripheral nerve injury is a common clinical issue induced by trauma, tumor, and damage caused by treatment. Such factors create chemical and inflammatory alterations at the injury site, which increase nerve deterioration. Thus, minimizing these modifications can lead to nerve protection after injury. The present study sought to evaluate the possible improvement in nerve regeneration and enhancement of functional outcomes by cinnamaldehyde (Cin) administration following sciatic nerve crush in a rat model. Rats (n = 48) were distributed into 6 groups, including sham, injury, DMSO (vehicle group), and Cin groups (10, 30, and 90 mg/kg/day). Using small hemostatic forceps, crush injury was induced in the left sciatic nerve. Thereafter, Cin was administered for 28 successive days. Weekly records were taken for sciatic functional index (SFI) measurements. Further assessments including electrophysiological and histomorphometric evaluations, gastrocnemius muscle wet weight measurements, and estimation of the serum total oxidant status were performed. According to the results, Cin could accelerate sciatic nerve recovery after crush injury, and the dose of 30 mg/kg/day of Cin had better impacts on SFI recovery, muscle mass ratio, and myelin content. The current research demonstrated that Cin positively affects peripheral nerve restoration. Therefore, Cin therapy could be considered as a potential treatment method for peripheral nerve regeneration and its functional recovery. However, more investigations are required to further validate the study results and evaluate the optimal dose of Cin.

Tramadol: a Potential Neurotoxic Agent Affecting Prefrontal Cortices in Adult Male Rats and PC-12 Cell Line

Tramadol is a synthetic analogue of codeine that is often prescribed for the treatment of mild to moderate pains. It has a number of side effects including emotional instability and anxiety. In this study, we focus on the structural and functional changes of prefrontal cortex under chronic exposure to tramadol. At the cellular level, the amounts of ROS and annexin V in PC12 cells were evidently increased upon exposure to tramadol (at a concentration of 600 μM for 48 h). To this end, the rats were daily treated with tramadol at doses of 50 mg/kg for 3 weeks. Our findings reveal that tramadol provokes atrophy and apoptosis by the induction of apoptotic markers such as Caspase 3 and 8, pro-inflammatory markers, and downregulation of GDNF. Moreover, it triggers microgliosis and astrogliosis along with neuronal death in the prefrontal cortex. Behavioral disturbance and cognitive impairment are other side effects of tramadol. Overall, our results indicate tramadol-induced neurodegeneration in the prefrontal cortex mainly through activation of neuroinflammatory response.

Tracking tumor radiotherapy response in vivo with Cherenkov-excited luminescence ink imaging

This study demonstrates remote imaging for in vivo detection of radiation-induced tumor microstructural changes by tracking the diffusive spread of injected intratumor UV excited tattoo ink using Cherenkov-excited luminescence imaging (CELI). Micro-liter quantities of luminescent tattoo ink with UV absorption and visible emission were injected at a depth of 2 mm into mouse tumors prior to receiving a high dose treatment of radiation. X-rays from a clinical linear accelerator were used to excite phosphorescent compounds within the tattoo ink through Cherenkov emission. The in vivo phosphorescence was detected using a time-gated intensified CMOS camera immediately after injection, and then again at varying time points after the ink had broken down with the apoptotic tumor cells. Ex vivo tumors were imaged post-mortem using hyperspectral cryo-fluorescence imaging to quantify necrosis and compared to Cherenkov-excited light imaging of diffusive ink spread measured in vivo. Imaging of untreated control mice showed that ink distributions remained constant after four days with less than 3% diffusive spread measured using full width at 20% max. For all mice, in vivo CELI measurements matched within 12% of the values estimated by the high-resolution ex vivo sliced luminescence imaging of the tumors. The tattoo ink spread in treated mice was found to correlate well with the nonperfusion necrotic core volume (R2 = 0.92) but not well with total tumor volume changes (R2 = 0.34). In vivo and ex vivo findings indicate that the diffusive spread of the injected tattoo ink can be related to radiation-induced necrosis, independent of total tumor volume change. Tracking the diffusive spread of the ink allows for distinguishing between an increase in tumor size due to new cellular growth and an increase in tumor size due to edema. Furthermore, the imaging resolution of CELI allows for in vivo tracking of subtle microenvironmental changes which occur earlier than tumor shrinkage and this offers the potential for novel, minimally invasive radiotherapy response assay without interrupting a singular clinical workflow.

Understanding resolution of inflammation in periodontal diseases: Is chronic inflammatory periodontitis a failure to resolve?

Periodontitis is an infectious-inflammatory disease that results from loss of balance between the commensal microbiome and the host response. The hyper-inflammatory, uncontrolled inflammatory immune lesion promotes tissue damage and impedes effective bacterial clearance. In this review, the relationship between the microbiome and the inflammatory/immune response is explored in the context of a bi-directional pathogenesis; bacteria induce inflammation and inflammation modifies the growth environment causing shifts in the composition of the microbiome. Resolution of inflammation is an active, receptor-mediated process induced by specialized pro-resolving lipid mediators. Inflammatory disease may, therefore, be the result of failure of resolution. Failure to resolve inflammation coupled with resultant microbiome changes is hypothesized to drive development of periodontitis. Re-establishment of microbiome/host homeostasis by specialized pro-resolving lipid mediator therapy suggests that microbiome dysbiosis, the host hyperinflammatory phenotype, and periodontitis can be reversed.

Chemerin: A Potential Regulator of Inflammation and Metabolism for Chronic Obstructive Pulmonary Disease and Pulmonary Rehabilitation

Chronic obstructive pulmonary disease (COPD) features chronic inflammatory reactions of both intra- and extrapulmonary nature. Moreover, COPD is associated with abnormal glucose and lipid metabolism in patients, which influences the prognosis and chronicity of this disease. Abnormal glucose and lipid metabolism are also closely related to inflammation processes. Further insights into the interactions of inflammation and glucose and lipid metabolism might therefore inspire novel therapeutic interventions to promote lung rehabilitation. Chemerin, as a recently discovered adipokine, has been shown to play a role in inflammatory response and glucose and lipid metabolism in many diseases (including COPD). Chemerin recruits inflammatory cells to sites of inflammation during the early stages of COPD, leading to endothelial barrier dysfunction, early vascular remodeling, and angiogenesis. Moreover, it supports the recruitment of antigen-presenting cells that guide immune cells as part of the body's inflammatory responses. Chemerin also regulates metabolism via activation of its cognate receptors. Glucose homeostasis is affected via effects on insulin secretion and sensitivity, and lipid metabolism is changed by increased transformation of preadipocytes to mature adipocytes through chemerin-binding receptors. Controlling chemerin signaling may be a promising approach to improve various aspects of COPD-related dysfunction. Importantly, several studies indicate that chemerin expression in vivo is influenced by exercise. Although available evidence is still limited, therapeutic alterations of chemerin activity may be a promising target of therapeutic approaches aimed at the rehabilitation of COPD patients based on exercises. In conclusion, chemerin plays an essential role in COPD, especially in the inflammatory responses and metabolism, and has a potential to become a target for, and a biomarker of, curative mechanisms underlying exercise-mediated lung rehabilitation.

The clearance of dead cells by efferocytosis

Multiple modes of cell death have been identified, each with a unique function and each induced in a setting-dependent manner. As billions of cells die during mammalian embryogenesis and daily in adult organisms, clearing dead cells and associated cellular debris is important in physiology. In this Review, we present an overview of the phagocytosis of dead and dying cells, a process known as efferocytosis. Efferocytosis is performed by macrophages and to a lesser extent by other 'professional' phagocytes (such as monocytes and dendritic cells) and 'non-professional' phagocytes, such as epithelial cells. Recent discoveries have shed light on this process and how it functions to maintain tissue homeostasis, tissue repair and organismal health. Here, we outline the mechanisms of efferocytosis, from the recognition of dying cells through to phagocytic engulfment and homeostatic resolution, and highlight the pathophysiological consequences that can arise when this process is abrogated.

Ranunculus bulumei Methanol Extract Exerts Anti-Inflammatory Activity by Targeting Src/Syk in NF-κB Signaling

(1) Background: Ranunculus bulumei is a flowering plant that belongs to the Ranunculus species. Several Ranunculus species, such as R. aquatilis and R. muricatus, have traditionally been used to treat fever and rheumatism throughout Asia, suggesting that plants belonging to the Ranunculus species may have anti-inflammatory effects. To our knowledge, the pharmacological activity of R. bulumei has not been reported. Therefore, in this study, we aim to assess the anti-inflammatory activity of a methanol extract that was derived from R. bulumei (Rb-ME) in macrophage-mediated inflammatory responses and to identify the molecular mechanism that underlies any anti-inflammatory action. (2) Methods: The anti-inflammatory efficacy of Rb-ME was evaluated while using in vitro and in vivo experiments. The RAW264.7 cells and peritoneal macrophages were stimulated by lipopolysaccharide (LPS). In addition, LPS-induced peritonitis and HCl/EtOH-triggered gastritis models were produced. A nitric oxide (NO) assay, real-time PCR, luciferase reporter gene assay, western blot analysis, plasmid overexpression strategy, and in vitro kinase assay were used to determine the molecular mechanisms and target molecules of Rb-ME. The phytochemical active ingredients of Rb-ME were also identified by high performance liquid chromatograph (HPLC). (3) Results: Rb-ME reduced the production of NO and mRNA expression of iNOS, COX-2, IL-1β, and IL-6 without cytotoxicity. The protein secretion of TNF-α and IL-6 was also decreased by Rb-ME. HPLC analysis indicates that quercetin, luteolin, and kaempferol are the main active ingredients in the anti-inflammatory efficacy of Rb-ME. Rb-ME also blocked MyD88-induced NF-κB promoter activity and nuclear translocation of NF-κB subunits (p65 and p50). Moreover, Rb-ME reduced the phosphorylation of IκBα, Akt, p85, Src, and Syk, which are NF-κB upstream signaling molecules in LPS-activated RAW264.7 cells. According to the in vitro kinase assay, Rb-ME directly inhibits Syk kinase activity. The oral administration of Rb-ME alleviated inflammatory responses and the levels of p-IκBα in mice with LPS-induced peritonitis and HCl/EtOH-induced gastritis. (4) Conclusions Rb-ME has anti-inflammatory capacity by suppressing NF-κB signaling and it has been found to target Src and Syk in the NF-κB pathway. Based on this efficacy, Rb-ME could be developed as an anti-inflammatory herbal medicine.

Integrative Radiogenomics Approach for Risk Assessment of Post-Operative Metastasis in Pathological T1 Renal Cell Carcinoma: A Pilot Retrospective Cohort Study

Despite the increasing incidence of pathological stage T1 renal cell carcinoma (pT1 RCC), postoperative distant metastases develop in many surgically treated patients, causing death in certain cases. Therefore, this study aimed to create a radiomics model using imaging features from multiphase computed tomography (CT) to more accurately predict the postoperative metastasis of pT1 RCC and further investigate the possible link between radiomics parameters and gene expression profiles generated by whole transcriptome sequencing (WTS). Four radiomic features, including the minimum value of a histogram feature from inner regions of interest (ROIs) (INNER_Min_hist), the histogram of the energy feature from outer ROIs (OUTER_Energy_Hist), the maximum probability of gray-level co-occurrence matrix (GLCM) feature from inner ROIs (INNER_MaxProb_GLCM), and the ratio of voxels under 80 Hounsfield units (Hus) in the nephrographic phase of postcontrast CT (Under80HURatio), were detected to predict the postsurgical metastasis of patients with pathological stage T1 RCC, and the clinical outcomes of patients could be successfully stratified based on their radiomic risk scores. Furthermore, we identified heterogenous-trait-associated gene signatures correlated with these four radiomic features, which captured clinically relevant molecular pathways, tumor immune microenvironment, and potential treatment strategies. Our results of accurate surrogates using radiogenomics could lead to additional benefit from adjuvant therapy or postsurgical metastases in pT1 RCC.

Dietary supplementation with free methionine or methionine dipeptide improves environment intestinal of broilers challenged with Eimeria spp

This study examined the influence of a diet enriched with free methionine (dl-Met) or methionine dipeptide (dl-MMet) on the intestinal health of Eimeria-challenged (EC) and unchallenged (UC) broilers. A non-supplemented, methionine-deficient diet (NS) was used as control. Treatments were arranged in a 2 × 3 factorial completely randomized design with eight replications. Broilers in the EC group were infected with sporulated oocysts of Eimeria spp. (E. acervulina, E. maxima, E. praecox, and E. mitis) at 14 d of age. Performance analysis, light and electron microscopy of the jejunum, analysis of genes related to apoptosis and cell proliferation in the jejunum, and blood tests were performed at 6 days post-inoculation (dpi). EC broilers had poorer performance than UC broilers, regardless of diet (P < 0.001). Broilers fed the dl-Met diet had greater weight gain (P = 0.004) and lower feed conversion ratio (P = 0.019) than broilers fed other diets. Jejunal sections from EC broilers fed the NS diet showed short (P = 0.001) and wide villi (P < 0.001) with increased crypt depth (P < 0.001) and reduced villus / crypt ratio (P = 0.001), jejunal absorptive surface area (P < 0.001), number of neutral goblet cells (Eimeria challenge: P = 0.048; diet P = 0.016), and mucin 2 (MUC2) gene expression (P = 0.018). EC birds fed the dl-MMet diet had higher enterocyte height (P < 0.001). Birds fed the dl-MMet diet had low lamina propria width (P = 0.009). UC broilers fed the dl-Met diet had the highest number of acidic goblet cells (P = 0.005), whereas EC broilers assigned the dl-MMet diet showed the highest number of intraepithelial lymphocytes (P = 0.033). Reduced expression of caspase-3 (CASP3) (P = 0.005), B-cell lymphoma 2 (BCL2) (P < 0.001), mechanistic target of rapamycin (MTOR) (P < 0.001), and ribosomal protein S6 kinase B1 (RPS6KB1) (P < 0.001) genes was observed in EC animals. MTOR expression levels were highest in birds fed the dl-MMet diet (P = 0.004). Plasma activities of aspartate aminotransferase (AST) was influenced by both diet (P = 0.002) and Eimeria challenge (P = 0.005), with EC broilers assigned the NS diet showing the highest levels. EC broilers fed the NS diet had higher creatine kinase (CK) activity (P = 0.049). EC broilers had lower plasma uric acid (P = 0.004) and higher serum mucoproteins level (P < 0.001). These results indicate that methionine dipeptide supplementation is able to mitigate the harmful intestinal effects of Eimeria spp. in broilers.

Ammonia Scavenging Prevents Progression of Fibrosis in Experimental Nonalcoholic Fatty Liver Disease

BACKGROUND AND AIMS

In nonalcoholic fatty liver disease (NAFLD), fibrosis is the most important factor contributing to NAFLD-associated morbidity and mortality. Prevention of progression and reduction in fibrosis are the main aims of treatment. Even in early stages of NAFLD, hepatic and systemic hyperammonemia is evident. This is due to reduced urea synthesis; and as ammonia is known to activate hepatic stellate cells, we hypothesized that ammonia may be involved in the progression of fibrosis in NAFLD.

APPROACH AND RESULTS

In a high-fat, high-cholesterol diet-induced rodent model of NAFLD, we observed a progressive stepwise reduction in the expression and activity of urea cycle enzymes resulting in hyperammonemia, evidence of hepatic stellate cell activation, and progressive fibrosis. In primary, cultured hepatocytes and precision-cut liver slices we demonstrated increased gene expression of profibrogenic markers after lipid and/or ammonia exposure. Lowering of ammonia with the ammonia scavenger ornithine phenylacetate prevented hepatocyte cell death and significantly reduced the development of fibrosis both in vitro in the liver slices and in vivo in a rodent model. The prevention of fibrosis in the rodent model was associated with restoration of urea cycle enzyme activity and function, reduced hepatic ammonia, and markers of inflammation.

CONCLUSIONS

The results of this study suggest that hepatic steatosis results in hyperammonemia, which is associated with progression of hepatic fibrosis. Reduction of ammonia levels prevented progression of fibrosis, providing a potential treatment for NAFLD.

Dihydrotanshinone I Alleviates Spinal Cord Injury via Suppressing Inflammatory Response, Oxidative Stress and Apoptosis in Rats

Background

Spinal cord injury (SCI) is a serious nervous system injury, causing extremely low quality of life and immensurable economic losses. However, there is few therapies that can effectively cure the injury. The goal of the present study was to explore the potential therapeutic effects of dihydrotanshinone I (DI) for SCI and the involving mechanism.

Material/Methods

A SCI rat model was structured to investigate the effects of DI on recovery of SCI. Tarlov’s scale was employed to assess the neuronal function and histopathological examination was carried out by hematoxylin and eosin staining. In addition, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, inducible nitric oxide synthase (iNOS), total oxidant status (TOS) and total antioxidant status (TAS) levels were detected. Tunel assay and western blot analysis were performed to evaluate cell apoptosis. Furthermore, western blot assay was used to measure the protein expressions.

Results

The results demonstrated that the treatment of DI alleviated the pathological damage induced by SCI and promoted the neuronal functional recovery. DI suppressed TNF-α, IL-1β, IL-6, iNOS, and TOS levels while improved the TAS level. Moreover, increased cell apoptosis in SCI rats was inhibited by administration of DI. Most importantly, DI reserved the soaring of TLR4, MyD88, HMGB1, and NOX4 level after induction of SCI. Thus, the observation revealed that the HMGB1/TLR4/NOX4 pathway may be involved in the protective effects of DI on SCI.

Conclusions

In conclusion, the findings suggest that DI alleviates SCI by restraining secretion of inflammatory factors, and occurrence of oxidative stress and apoptosis in vivo. DI may be developed into an effective alternative therapy for SCI in clinic.

Caspase-11 promotes allergic airway inflammation

Activated caspase-1 and caspase-11 induce inflammatory cell death in a process termed pyroptosis. Here we show that Prostaglandin E₂ (PGE₂) inhibits caspase-11-dependent pyroptosis in murine and human macrophages. PGE₂ suppreses caspase-11 expression in murine and human macrophages and in the airways of mice with allergic inflammation. Remarkably, caspase-11-deficient mice are strongly resistant to developing experimental allergic airway inflammation, where PGE₂ is known to be protective. Expression of caspase-11 is elevated in the lung of wild type mice with allergic airway inflammation. Blocking PGE₂ production with indomethacin enhances, whereas the prostaglandin E₁ analog misoprostol inhibits lung caspase-11 expression. Finally, alveolar macrophages from asthma patients exhibit increased expression of caspase-4, a human homologue of caspase-11. Our findings identify PGE₂ as a negative regulator of caspase-11-driven pyroptosis and implicate caspase-4/11 as a critical contributor to allergic airway inflammation, with implications for pathophysiology of asthma.

Caspase 11 activation involves transcriptional upregulation and proteolytic cleavage. Here the authors show that prostaglandin E₂ prevents caspase-11-mediated pyroptosis, blocking caspase-11 mRNA and protein upregulation in macrophages and in vivo, and that mice lacking caspase-11 are strongly protected from allergic airway inflammation.

Inflammation-dependent downregulation of miR-532-3p mediates apoptotic signaling in human sarcopenia through targeting BAK1

Inflammation and apoptosis are considered as two major pathological causes of human sarcopenia. The current understanding based on different models recognizes that apoptosis does not trigger inflammation, while emerging evidence indicates that inflammation can induce apoptosis. Here, we provide solid evidence to suggest that the inflammation-dependent downregulation of miR-532 causes apoptosis through targeting a proapoptotic gene BAK1 (BCL2 antagonist/killer 1). To identify miRNAs and genes that are aberrantly expressed in the muscle tissues of sarcopenia patients, we conducted two independent microarray analyses. In total, we identified 53 miRNAs and 69 genes with differential expression levels. Of these aberrantly expressed miRNAs, miR-532-3p showed the most obvious changes in sarcopenia tissues, and more importantly, it can be repressed by the well-known inflammatory inducer lipopolysaccharide (LPS) in vitro. According to gene-based microarray results and the predicted targets of miR-532-3p, we presumed that BAK1 was a putative target of miR-532-3p. Further in vitro and in vivo analyses verified that miR-532-3p could directly bind to the three prime untranslated region (3'-UTR) of BAK1 through the seed sequence CUCCCAC. In addition, we found that NFKB1 (also known as p50), a subunit of the transcription factor NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells), could specifically bind to the promoter region of miR-532-3p and repress its expression. Further analysis revealed that the activation of TLR4 (Toll-like receptor 4) signaling led to the translocation of p50 from the cytoplasm to the nucleus, where it repressed miR-532-3p expression and thus led to an increase of BAK1. The accumulated BAK1 activated its downstream apoptotic signaling pathways and resulted in apoptosis, eventually causing the pathogenesis underlying sarcopenia. Overall, our results uncovered a new mechanism by which the inflammation-dependent downregulation of miR-532-3p contributed to the pathogenesis of sarcopenia through mediating BAK1 expression.

Telomere length and cardiovascular disease risk

PURPOSE OF REVIEW

Telomere length has been hypothesized as a putative biomarker for cardiovascular disease. However, the findings are mixed and shared confounding factors may explain these associations. The current review aims to summarize the recent literature on the role of telomere length in cardiovascular disease and give directions for future potential as a predictive biomarker.

RECENT FINDINGS

In this review, we outline the biology of telomeres as a biomarker of aging through its shortening capacity across the life course. Recent epidemiological evidence for its associations with cardiovascular risk factors and disease is discussed. Then we highlight the possible causal role of telomeres in coronary heart disease and summarize the potential biological mechanisms and pathways known.

SUMMARY

The current research and results presented on telomere length may implicate that short telomeres are causal risk factors for cardiovascular disease, partially through insulin-mediated pathways. Nevertheless, further studies with refined quantification methods and larger populations are needed to clarify the added role of telomere length in predicting future risks of cardiovascular disease on top of existing risk biomarkers, and whether it may be amenable for intervention.

Time-resolved proteomic profile of Amblyomma americanum tick saliva during feeding

Amblyomma americanum ticks transmit more than a third of human tick-borne disease (TBD) agents in the United States. Tick saliva proteins are critical to success of ticks as vectors of TBD agents, and thus might serve as targets in tick antigen-based vaccines to prevent TBD infections. We describe a systems biology approach to identify, by LC-MS/MS, saliva proteins (tick = 1182, rabbit = 335) that A. americanum ticks likely inject into the host every 24 h during the first 8 days of feeding, and towards the end of feeding. Searching against entries in GenBank grouped tick and rabbit proteins into 27 and 25 functional categories. Aside from housekeeping-like proteins, majority of tick saliva proteins belong to the tick-specific (no homology to non-tick organisms: 32%), protease inhibitors (13%), proteases (8%), glycine-rich proteins (6%) and lipocalins (4%) categories. Global secretion dynamics analysis suggests that majority (74%) of proteins in this study are associated with regulating initial tick feeding functions and transmission of pathogens as they are secreted within 24–48 h of tick attachment. Comparative analysis of the A. americanum tick saliva proteome to five other tick saliva proteomes identified 284 conserved tick saliva proteins: we speculate that these regulate critical tick feeding functions and might serve as tick vaccine antigens. We discuss our findings in the context of understanding A. americanum tick feeding physiology as a means through which we can find effective targets for a vaccine against tick feeding.

The lone star tick, Amblyomma americanum, is a medically important species in US that transmits 5 of the 16 reported tick-borne disease agents. Most recently, bites of this tick were associated with red meat allergies in humans. Vaccination of animals against tick feeding has been shown to be a sustainable and an effective alternative to current acaricide based tick control method which has several limitations. The pre-requisite to tick vaccine development is to understand the molecular basis of tick feeding physiology. Toward this goal, this study has identified proteins that A. americanum ticks inject into the host at different phases of its feeding cycle. This data set has identified proteins that A. americanum inject into the host within 24–48 h of feeding before it starts to transmit pathogens. Of high importance, we identified 284 proteins that are present in saliva of other tick species, which we suspect regulate important role(s) in tick feeding success and might represent rich source target antigens for a tick vaccine. Overall, this study provides a foundation to understand the molecular mechanisms regulating tick feeding physiology.