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Apoptosis, autophagy and necrosis are the three main types of programmed cell death. One or more of these types of programmed cell death may take place in neurons leading to their death in various neurodegenerative disorders in humans. Purkinje neurons (PNs) are among the most highly vulnerable population of neurons to cell death in response to intrinsic hereditary diseases or extrinsic toxic, hypoxic, ischemic, and traumatic injury. In this review, we will describe the three main types of programmed cell death, including the molecular mechanisms and the sequence of events in each of them, and thus illustrating the intracellular proteins that mediate and regulate each of these types. Then, we will discuss the role of Ca2+ in PN function and increased vulnerability to cell death. Additionally, PN death will be described in animal models, namely lurcher mutant mouse and shaker mutant rat, in order to illustrate the potential therapeutic implications of programmed cell death in PNs by reviewing the previous studies that were carried out to interfere with the programmed cell death in an attempt to rescue PNs from death., Competing Interests: The author declares no conflict of interest., (© 2022 The Author(s). Published by IMR Press.)

Objective: The aim of the study was to investigate radiomics models based on magnetic resonance imaging (MRI) for predicting early extrapancreatic necrosis (EXPN) in acute pancreatitis., Methods: Radiomics features were extracted from T2-weighted images of extrapancreatic collections and late arterial-phase images of the pancreatic parenchyma for 135 enrolled patients (94 in the primary cohort, including 47 EXPN patients and 41 in the validation cohort, including 20 EXPN patients). The optimal features after dimension reduction were used for radiomics modeling through a support vector machine. A clinical model, the MR severity index score, and extrapancreatic inflammation on MRI were evaluated., Results: Twelve optimal features from the extrapancreatic collection images and 10 from the pancreatic parenchyma images were selected for modeling. The pancreatic parenchyma-based and extrapancreatic collection-based radiomics models showed good predictive accuracy in both the training and validation cohorts. The areas under the curve of the extrapancreatic collection-based radiomics model (0.969 and 0.976) were consistent with those of the pancreatic parenchyma-based model (0.931 and 0.921) for both cohorts and better than those of the clinical model and imaging scores for both cohorts., Conclusions: The MRI-based radiomics models of both the extrapancreatic collections and the pancreatic parenchyma had excellent predictive performance for early EXPN., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

The death of endocrine cells is involved in type 1 diabetes mellitus, autoimmunity, adrenopause and hypogonadotropism. Insights from research on basic cell death have revealed that most pathophysiologically important cell death is necrotic in nature, whereas regular metabolism is maintained by apoptosis programmes. Necrosis is defined as cell death by plasma membrane rupture, which allows the release of damage-associated molecular patterns that trigger an immune response referred to as necroinflammation. Regulated necrosis comes in different forms, such as necroptosis, pyroptosis and ferroptosis. In this Perspective, with a focus on the endocrine environment, we introduce these cell death pathways and discuss the specific consequences of regulated necrosis. Given that clinical trials of necrostatins for the treatment of autoimmune conditions have already been initiated, we highlight the therapeutic potential of such novel therapeutic approaches that, in our opinion, should be tested in endocrine disorders in the future., (© 2021. Springer Nature Limited.)

Gliomas are primary brain tumors with a high invasive potential and infiltrative spread. Among them, glioblastoma multiforme (GBM) exhibits microvascular hyperplasia and pronounced necrosis triggered by hypoxia. Histological samples showing garland-like hypercellular structures (so-called pseudopalisades) centered around the occlusion site of a capillary are typical for GBM and hint on poor prognosis of patient survival. We propose a multiscale modeling approach in the kinetic theory of active particles framework and deduce by an upscaling process a reaction-diffusion model with repellent pH-taxis. We prove existence of a unique global bounded classical solution for a version of the obtained macroscopic system and investigate the asymptotic behavior of the solution. Moreover, we study two different types of scaling and compare the behavior of the obtained macroscopic PDEs by way of simulations. These show that patterns (not necessarily of Turing type), including pseudopalisades, can be formed for some parameter ranges, in accordance with the tumor grade. This is true when the PDEs are obtained via parabolic scaling (undirected tissue), while no such patterns are observed for the PDEs arising by a hyperbolic limit (directed tissue). This suggests that brain tissue might be undirected - at least as far as glioma migration is concerned. We also investigate two different ways of including cell level descriptions of response to hypoxia and the way they are related .

Heart failure (HF) represents one of the leading causes of cardiovascular diseases with high rates of hospitalization, morbidity and mortality worldwide. Ample evidence has consolidated a crucial role for mitochondrial injury in the progression of HF. It is well established that mitochondrial Ca 2+ participates in the regulation of a wide variety of biological processes, including oxidative phosphorylation, ATP synthesis, reactive oxygen species (ROS) generation, mitochondrial dynamics and mitophagy. Nonetheless, mitochondrial Ca 2+ overload stimulates mitochondrial permeability transition pore (mPTP) opening and mitochondrial swelling, resulting in mitochondrial injury, apoptosis, cardiac remodeling, and ultimately development of HF. Moreover, mitochondria possess a series of Ca 2+ transport influx and efflux channels, to buffer Ca 2+ in the cytoplasm. Interaction at mitochondria-associated endoplasmic reticulum membranes (MAMs) may also participate in the regulation of mitochondrial Ca 2+ homeostasis and plays an essential role in the progression of HF. Here, we provide an overview of regulation of mitochondrial Ca 2+ homeostasis in maintenance of cardiac function, in an effort to identify novel therapeutic strategies for the management of HF.

Early diagnosis of cantharidin-induced myocardial injury is the key to reduce the fatality rate in clinical practice. The purpose of the present study was to explore biomarkers that can be used for the prediction and diagnosis of cantharidin-induced myocardial injury. Of 65 male Sprague-Dawley rats weighing 200-230 g, 25 rats were divided into five groups according to the administration dose of cantharidin (0, 1.34, 2.67, 4 and 5.34 mg/kg; n = 5 per group) and the other 40 rats were treated with 2.67 mg/kg cantharidin and divided into nine groups according to the administration time (0, 1, 2, 4, 6, 8, 12, 24, 48 and 72 hours; n = 4 per group). Pathological changes of hypoxia, necrosis and inflammation were confirmed in heart samples that were exposed to cantharidin by hematoxylin-eosin staining and overall scores of pathological changes among heart samples in cantharidin exposure groups showed an increasing trend compared with in the control group. Coexpression of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α (HIF-1α) and caspase9 was shown in the myocardium by immunofluorescence staining. Western blotting results showed that expression of VEGF, HIF-1α and caspase9 in cantharidin-treated rat hearts showed an increasing trend compared with in the control group. Results of enzyme-linked immunosorbent assay suggested that plasma levels of troponin T (TN-T), VEGF and HIF-1α were elevated at different intervals after cantharidin administration, and VEGF and HIF-1α had a significant linear relationship with TN-T that was verified by multiple linear regression analysis. Preliminary results serve to illustrate that TN-T, VEGF and HIF-1α might be valuable molecular markers in cantharidin-induced myocardial injury and that diagnostic accuracy needs to be studied further., (© 2020 John Wiley & Sons, Ltd.)

Ferroptosis is a newly discovered type of cell death triggered by intracellular phospholipid peroxidation that is morphologically, biologically and genetically distinct from other types of cell death. Ferroptosis is classified as regulated necrosis and is more immunogenic than apoptosis. To date, compelling evidence indicates that ferroptosis plays an important role in inflammation, and several antioxidants functioning as ferroptosis inhibitors have been shown to exert anti-inflammatory effects in experimental models of certain diseases. Our review provides an overview of the link between ferroptosis and inflammation; a better understanding of the mechanisms underlying ferroptosis and inflammation may hasten the development of promising therapeutic strategies involving ferroptosis inhibitors to address inflammation., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest., (Copyright © 2020 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Oxidative stress may result in different modes of cell death, such as necrosis, apoptosis and necroptosis. Currently, researchers are still striving to develop efficient tools/methods to distinguish the cell death modes in direct and label-free ways. In this study, we attempted to employ Raman micro-spectroscopy to observe the molecular changes in Candida utilis cells under oxidative stress induced by low-temperature plasma (LTP) and explore the spectroscopic biomarkers for the modes of cell death under oxidative stress. In this research, we confirmed that LTP could impose oxidative stress on the yeast cells, and recorded the changes of Raman signals of cytochrome c in the cells under LTP oxidative stress. Subsequently, we identified the biochemical and morphological characteristic features corresponding to different modes of cell death. Interestingly, we found that LTP under certain conditions could induce oxidative stress which caused the yeast cell death mainly by means of necroptosis, which was verified by Annexin V/PI, HMGB1 location assay and immunoprecipitation assay of the RIP1/RIP3 necrosome. Correspondingly, we also showed that the LTP induced necroptosis, associated with the increase of cytoplasmic Ca 2+ and mitochondrial ROS, the decrease of mitochondrial membrane potential, the release of oxidized cytochrome c from the mitochondrion to the cytoplasm, and the destruction of mitochondria in yeast cells. This work has therefore demonstrated that monitoring the redox state of cytochrome c using Raman micro-spectroscopy is very useful for distinguishing the modes of cell death and particularly may unveil the unique necroptosis process of cells under extrinsic oxidative stress.

Background: Levamisole is an immunomodulatory medication previously used to treat rheumatoid arthritis and some types of cancers; it was banned for use in humans in 2000 owing to its harmful side effects. Use of levamisole-laced cocaine is associated with a life-threatening syndrome characterized by a necrotizing purpuric rash leading to tissue destruction and necrotic wounds. This Clinical Challenges article summarizes our experience with the care of 2 adult women diagnosed with levamisole-related vasculitis., Case: Case 1 is a 46-year-old woman who presented with joint pain in her hands and legs, along with bilateral ear pain, swelling, and bleeding. She was initially diagnosed with vasculitis and possible systemic lupus erythematosus. She experienced multiple recurrences and exacerbation of her condition over a period of months. She was ultimately diagnosed with levamisole-related vasculitis from recurrent cocaine use resulting in bilateral above the knee amputations. The second case is a 50-year-old woman who presented to our emergency department with redness and swelling of her bilateral lower extremities. She developed blisters and pustules that rapidly evolved into abscesses and red lesions over the course of several months. Her wounds also deteriorated despite topical therapy that occurred in a context of recurring use of cocaine., Conclusions: Our experience with these cases suggests that WOC nurses should consider levamisole-induced vasculitis in all patients presenting with unexplained vasculitis-type lesions, and particularly when these lesions occur in the context of known or suspected use of illicit substances such as cocaine. Given the absence of clinical guidelines for this increasingly prevalent condition, we recommend wound care based on principles of moist wound healing, combined with judicious use of therapies with antimicrobial activity and nonadherent dressings to reduce pain. Finally, we strongly recommend that care of these patients occurs as one part of a multidisciplinary care approach that focuses on cessation of the use of cocaine and all other illicit substances.

Immune-mediated necrotising myopathy (IMNM) is a recently described entity. We describe a cohort of South Australian IMNM patients in order to define the spectrum of disease, characterise features that distinguish IMNM from other idiopathic inflammatory myopathy (IIM) subtypes and identify factors associated with clinically severe disease. Subjects were identified from the South Australian Myositis Database (SAMD), a histologically defined registry. Consecutive muscle sections from patients with IMNM (n = 62), other forms of IIM (n = 60) and histologically normal muscle (n = 17) were stained using immunohistochemistry and graded. Clinical information was collected from the SAMD and through retrospective chart review. IMNM patients displayed clinical and histological heterogeneity. While most (67%) were profoundly weak at presentation, 24% exhibited mild to moderate weakness and 9% had normal power. Histological myonecrosis ranged from minor to florid. The amount of myofibre complement deposition was closely associated with clinical severity. Patients of Aboriginal and Torres Strait Islander heritage and those with anti-SRP autoantibodies present with a severe phenotype. Despite intense immunotherapy, few IMNM patients recovered full power at one year follow up. The identification of clinical, serological and histological features which are associated with severe forms of the disease may have diagnostic and therapeutic utility., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Long-term or heavy use of glucocorticoids can cause severe necrosis of the femoral head, but the underlying mechanisms are still unclear. Recent studies have found that mitochondrial dynamics play an important role in femoral head necrosis. Here, we investigated the effect of dexamethasone on the mitochondrial function of mesenchymal stem cells. We observed that high concentrations of dexamethasone (10 -6  mol·L -1 ) decreased cell activity, promoted apoptosis, elevated levels of reactive oxygen species and disrupted mitochondrial dynamics. Furthermore, dexamethasone (10 -6  mol·L -1 ) inhibited osteogenesis of stem cells and promoted adipogenesis. These findings may facilitate greater understanding of the adverse effects of dexamethasone on the femoral head., (© 2019 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

Competing Interests: Dr. Thompson is a consultant for Boston Scientific, Olympus, Medtronic, Apollo Endosurgery, and USGI Medical.All other authors have no conflict of interest.

Traumatic brain injury (TBI) is defined as damage to the brain that consequently disrupts normal function. Neuronal death, a hallmark of TBI, has been related to the development of neurodegenerative disorders like Parkinson's disease (PD), where loss of dopaminergic neurons and dopaminergic dysfunction are observed. To date, no in vitro model exists in which the dopaminergic damage observed in TBI is replicated. In this study, we evaluated the effects of in vitro simulated TBI on human dopaminergic neurons. To simulate TBI, neurons were subjected to 0%, 5%, 10%, 15%, 25% and 50% deformation. 24 h after injury, cell viability and apoptosis were determined by lactate dehydrogenase (LDH) release and DNA fragmentation, as well as ethidium homodimer and caspase 3/7 staining. Dopamine (DA) levels were determined by ELISA. Levels of tyrosine hydroxylase (TH) and DA transporter (DAT) were determined by western blot. Only 50% stretch increased LDH release and ethidium homodimer staining, suggesting the induction of necrosis. On the contrary, 25% and 50% stretch increased DNA fragmentation while 15%, 25% and 50% increased caspase 3/7 staining, suggesting that moderate and severe TBI promote apoptosis. Levels of intracellular DA decreased in a stretch-dependent manner with 15%, 25% and 50% stretch, which were related with a decrease in TH expression. Extracellular DA levels increased only at 50%. Levels of DAT remained unchanged regardless of treatment. These data support the use of stretch as a model to simulate TBI in vitro in human dopaminergic neurons, replicating the acute effects of TBI in the dopaminergic system.

The receptor-interacting serine/threonine-protein kinases RIPK1 and RIPK3 play important roles in necroptosis that are closely linked to the inflammatory response. Although the activation of necroptosis is well characterized, the mechanism that tunes down necroptosis is largely unknown. Here we find that Parkin (also known as PARK2), an E3 ubiquitin ligase implicated in Parkinson's disease and as a tumour suppressor, regulates necroptosis and inflammation by regulating necrosome formation. Parkin prevents the formation of the RIPK1-RIPK3 complex by promoting polyubiquitination of RIPK3. Parkin is phosphorylated and activated by the cellular energy sensor AMP-activated protein kinase (AMPK). Parkin deficiency potentiates the RIPK1-RIPK3 interaction, RIPK3 phosphorylation and necroptosis. Parkin deficiency enhances inflammation and inflammation-associated tumorigenesis. These findings demonstrate that the AMPK-Parkin axis negatively regulates necroptosis by inhibiting RIPK1-RIPK3 complex formation; this regulation may serve as an important mechanism to fine-tune necroptosis and inflammation.

Objective: To observe the effects of prolonged exposure to high concentrations of PM 2.5 on the trachea and lungs of mice and to determine whether the damages to the trachea and lung are induced by necroptosis., Methods: Six- to eight-week-old female Balb/C mice of PM group were restrained in an animal restraining device using a nose-only "PM 2.5 online enrichment system" for 8 weeks, in Shijiazhuang, Hebei, China. Anti -Fas group was exposed to PM 2.5 inhalation and anti-Fas treatment via intranasal instillation. The mice in the control group inhaled filtered clean air. PM 2.5 sample was collected and analyzed. Airway Hyperresponsiveness (AHR) was tested. Lung tissue and bronchoalveolar lavage fluid (BALF) were analyzed for Hematoxylin and eosin (HE) staining, electron microscopy, cellular inflammation, cytokines, Tunel, Fas, RIPK3 and MLKL expression., Results: Compared to the other two groups, PM group displayed significantly increased AHR, neutrophils in BALF, significant bronchitis and alveolar epithelial hyperplasia and inflammation and necroptosis which were indicated by increased TUNEL, Fas, RIPK3 and MLKL measure., Conclusion: Our findings suggest that PM 2.5 can enhance AHR and these changes are induced by necroptosis-related inflammation., (Copyright © 2019 Elsevier B.V. All rights reserved.)

BACKGROUND Although originally described as a survival mechanism, it is unknown whether and to what extent autophagy is implicated in the terminal stages of heart failure. Here, we studied magnitude and evolution of autophagy in patients with intractable heart failure. MATERIAL AND METHODS Myocardial samples were obtained from 22 patients with ischemic cardiomyopathy and idiopathic dilated cardiomyopathy who were undergoing cardiac transplantation. Hearts from 11 patients who died from non-cardiac causes were used as control samples. Autophagy was evaluated by immunostaining with a monoclonal microtubule associated protein light chain 3 (LC3)-II antibody, while the relationship of autophagy with apoptosis and oncosis was assessed by double staining with TUNEL (terminal deoxynucleotidyl transferase - mediated deoxyuridine triphosphate nick end labeling) assay and complement 9 (C9) immunological staining, respectively. In addition, several necroptotic markers, including RIP1 and RIP3 (receptor interacting protein kinase 1 and 3), anti-C3 (cleaved-caspase-3), and anti-NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) were assessed by immunohistochemistry. RESULTS Anti-LC3-II staining was detected in 8.7±1.6% of the heart failure patient heart samples and in 1.2±0.3% of control patient heart samples. Vacuole formation started at one nuclear pole, before becoming bipolar and involving the cytosol. Subsequently, the autophagic process extended also to the nuclei, which underwent a progressive vacuolization and disintegration, assuming a peculiar "strawberry like appearance". Myocytes with extensive vacuole formation exhibited nuclear degeneration, which was associated with TUNEL, C3, C9, RIP1, and RIP3 positive staining. Conversely, myocytes with less extensive vacuole formation showed RIP1 and NF-κB positive staining, though not positivity for other cell death markers. CONCLUSIONS Autophagy was extensively detected in end-stage heart failure and its progression, resulted in secondary cell death, with occurrence of oncosis and necroptosis exceeding that of apoptosis. Conversely, activation of the RIP1/NF-κB pathway was associated with cell survival.

Stress is deeply rooted in the modern society due to limited resources and large competition to achieve the desired goal. Women are more frequently exposed to several stressors during their reproductive age that trigger generation of reactive oxygen species (ROS). Accumulation of ROS in the body causes oxidative stress (OS) and adversely affects ovarian functions. The increased OS triggers various cell death pathways in the ovary. Beside apoptosis and autophagy, OS trigger necroptosis in granulosa cell as well as in follicular oocyte. The OS could activate receptor interacting protein kinase-1(RIPK1), receptor interacting protein kinase-3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL) to trigger necroptosis in mammalian ovary. The granulosa cell necroptosis may deprive follicular oocyte from nutrients, growth factors and survival factors. Under these conditions, oocyte becomes more susceptible towards OS-mediated necroptosis in the follicular oocytes. Induction of necroptosis in encircling granulosa cell and oocyte may lead to follicular atresia. Indeed, follicular atresia is one of the major events responsible for the elimination of majority of germ cells from cohort of ovary. Thus, the inhibition of necroptosis could prevent precautious germ cell depletion from ovary that may cause reproductive senescence and early menopause in several mammalian species including human.

Current clinical diagnosis is typically based on a combination of approaches including clinical examination of the patient, clinical experience, physiologic and/or genetic parameters, high-tech diagnostic medical imaging, and an extended list of laboratory values mostly determined in biofluids such as blood and urine. One could consider this as precision medicine v1.0. However, recent advances in technology and better understanding of molecular mechanisms underlying disease will allow us to better characterize patients in the future. These improvements will enable us to distinguish patients who have similar clinical presentations but different cellular and molecular responses. Treatments will be able to be chosen more "precisely", resulting in more appropriate therapy, precision medicine v2.0. In this review, we will reflect on the potential added value of recent advances in technology and a better molecular understanding of necrosis and inflammation for improving diagnosis and treatment of critically ill patients. We give a brief overview on the mutual interplay between necrosis and inflammation, which are two crucial detrimental factors in organ and/or systemic dysfunction. One of the challenges for the future will thus be the cellular and molecular profiling of necroinflammation in biofluids. The huge amount of data generated by profiling biomolecules and single cells through, for example, different omic-approaches is needed for data mining methods to allow patient-clustering and identify novel biomarkers. The real-time monitoring of biomarkers will allow continuous (re)evaluation of treatment strategies using machine learning models. Ultimately, we may be able to offer precision therapies specifically designed to target the molecular set-up of an individual patient, as has begun to be done in cancer therapeutics.

In the field of stem cell therapy, research on the application of mesenchymal stem cells (MSCs) has flourished because of the various functions. On the other hand, research on the method of cell transplantation has developed from the administration of cell suspensions to cell-sheet engineering and 3D technology. In the trend, a cell transplantation platform named CellSaic, which is a combination of xeno-free recombinant scaffolds in a cell aggregate-like shape, was developed. CellSaic is the cell transplantation platform that can prevent the central necrosis within cell aggregates by arranging the cells and petaloid pieces of recombinant peptide (RCP) in a mosaic. The prevention of central necrosis is the most significant advantage over other 3D culture systems. This review details the unique characteristics of CellSaic including safety examination results and describes its future application for MSC transplantation. Particularly, in the application of MSCs, it has been reported that the MSC CellSaics increased the effect on improving various symptoms compared with MSCs only in the application of the therapy to inflammatory bowel disease (IBD), cerebral infarction, bone cartilage regeneration in joints, and islet transplantation. In accordance with the "One Health" concept, it is anticipated that this technology is expected to contribute to companion animal therapy and human therapy in the future., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: To analyze the effectiveness of complex therapy of necrotizing infection using the original method of stimulation of angiogenesis in patients with chronic arterial insufficiency of the lower extremities., Material and Methods: In 53 patients, operations were performed using the proposed technologies for stimulation of angiogenesis. A control group consisting of 56 patients was formed to compare the results of treatment. They had standard vascular therapy for the correction of ischemia. Morphological studies of the muscles of the lower extremities included assessment of capillary bed density and spatial orientation of the capillaries before and after treatment. Computed angiography of the lower extremities followed by calculation of perfusion index was performed to assess changes in the microvasculature. Clinical evaluation of the results was carried out using R. Rutherford scale., Results: Revascularization resulted significant augmentation of capillary bed density and the number of functioning capillaries in muscular tissue. This was accompanied by increased perfusion index and TcPO 2 values. The effect of treatment is observed in 12-14 days after surgery and persists for a long time. The best outcomes are found in patients with ischemia grade IIb-III. Incidence of lower limb amputations was more than 2 times lower in the main group compared with the control group., Conclusion: Combined stimulation of angiogenesis including mechanical tunneling of the muscles of the affected limb and administration of platelet rich plasma is effective procedure. This method does not require complex equipment and may be used in the treatment of patients with complications of chronic lower limb ischemia and contraindicated direct arterial reconstruction.

Apoptosis is a prototype of regulated cell death and plays a crucial role in the development of various organs and maintaining tissue homeostasis. Recent studies have revealed that new types of regulated cell death, including necroptosis, ferroptosis, and pyroptosis are molecularly identified. In this review, we discuss the molecular mechanisms and the functions of new types of regulated cell death.

The RIPoptosome, composed of RIP1 and caspase-8, plays an important role in the regulation of apoptosis and necroptosis; however, the mechanism of complex formation by oligomerization and how the caspase-activating process and necroptosis are mediated by the formation of the RIPoptosome is not well-understood. This study revealed that the assembly mechanism of the RIPoptosome core is dependent on salt concentration and not on pH and time. In addition, we demonstrated that three RIP1 mutations, E626K, M637K, and S657K, have dominant negative effects. These dominant negative mutations in RIP1 may have potential applications in therapeutic intervention.

Necroptosis is a regulated form of necrosis that depends on receptor-interacting protein kinase (RIPK)3 and mixed lineage kinase domain-like (MLKL). While danger-associated molecular pattern (DAMP)s are involved in various pathological conditions and released from dead cells, the underlying mechanisms are not fully understood. Here we develop a fluorescence resonance energy transfer (FRET) biosensor, termed SMART (a sensor for MLKL activation by RIPK3 based on FRET). SMART is composed of a fragment of MLKL and monitors necroptosis, but not apoptosis or necrosis. Mechanistically, SMART monitors plasma membrane translocation of oligomerized MLKL, which is induced by RIPK3 or mutational activation. SMART in combination with imaging of the release of nuclear DAMPs and Live-Cell Imaging for Secretion activity (LCI-S) reveals two different modes of the release of High Mobility Group Box 1 from necroptotic cells. Thus, SMART and LCI-S uncover novel regulation of the release of DAMPs during necroptosis.

Deep tissue injuries (DTIs) are the manifestation of multiple layers of tissue necrosis and are often secondary to chronic mechanical stress to an area of bony prominence. The prevalence of these injuries among the chronically ill and patients in long-term care require a strong understanding of their etiology and a highly sensitive identification algorithm. Although the National Pressure Ulcer Advisory Panel (NPUAP) has released new guidelines with accurate descriptions as to how these injuries present, there is a significant segment of patients that present atypically and, as such, the treatment plan and prognosis are difficult to predict based on physical presentation, which can lead to either delays in necessarily aggressive care or conversely an overzealous treatment plan in hopes of addressing a pathology that may be self-limiting. Three cases of patients with a DTI, in which the initial presentation was not typical (ie, as described by the current NPUAP staging system) and not an accurate diagnostic predictor of prognosis, are presented. These differences, their course of treatment, and a more comprehensive diagnostic approach will be discussed in the hopes of more accurately identifying these injuries with a focus on prediction of disease trajectory.

The study investigated the ultrastructural characteristics of tubular gland and duct cells, as well as luminal gland cells in the isthmus region of the oviduct of laying and natural moulting hens. Tubular glands in laying birds were composed of type 1 and 2 cells. Based on the preponderance of each cell type, in relation to the location of a developing egg in the oviduct of the domestic fowl, these gland cells may represent different functional states of the same cell. The findings of the study on natural moulting birds suggest that autophagy is a process confined to the early stages of degeneration, while necrosis occurs in the terminal stages., (© 2018 Blackwell Verlag GmbH.)

Periodontal tissues are constantly exposed to microbial stimuli. The equilibrium between microbes and host defense system helps maintain the homeostasis in the periodontal microenvironment. Growth of pathogenic bacteria in dental biofilms may induce proinflammatory cytokine production to recruit sentinel cells, mainly neutrophils and monocytes into the gingival sulcus or the periodontal pocket. Moreover, dysbiosis with overgrowth of anaerobic pathogens, such as Porphyromonas gingivalis and Tannerella forsythia, may induce death of both immune cells and host resident cells. Necroptosis is one newly characterized programmed cell death mediated by receptor-interacting protein kinase (RIPK)-1, RIPK3, and mixed lineage kinase like (MLKL). With its release of death-associated molecular patterns (DAMPs) into extracellular environment, necroptosis may help transmit the danger signal and amplify the inflammatory responses. In this review, we present recent advances on how necroptosis influences bacterial infection progression and what a role necroptosis plays in maintaining the homeostasis in the periodontal niche. Until we fully decipher the signals emanated from dying cells, we cannot completely understand the mechanism of disease progression., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

Introduction: Resulting mostly from major injury or infection, severe acute wounds are often accompanied by septic shock or multiple organ failure and associated with high disability and mortality rates. In managing Chinese patients with wound-derived acute severe illnesses, salvage treatment in the emergency department has traditionally prioritized life support and protection of vital organs before wound repair., Objective: This retrospective review evaluated the outcomes of patients with wound-derived acute severe illness who were treated with a new salvage protocol that combined proactive wound care with simultaneous life-support measures., Materials and Methods: Records from 2011 to 2013 at Peking Union Medical College Hospital (PUMCH) in Beijing, China, were reviewed to identify patients with wound-derived acute severe illness treated with the new protocol. The plastic surgery department, emergency department, and intensive care unit developed the protocol, which included proactive wound treatment with negative pressure wound therapy (NPWT), interdepartmental cooperation, and comprehensive patient treatment., Results: Fifty-six patients were managed with the new protocol. At presentation, all patients were in septic shock and 29 of 56 (51.8%) required mechanical ventilation. Of the treated patients, 21 (37.5%) fully recovered and 29 (51.8%) improved sufficiently enough for transfer to a general ward. Six patients (10.7%) died of causes unrelated to NPWT., Conclusions: At PUMCH, the new collaborative salvage protocol with proactive use of NPWT with simultaneous life- support methods resulted in greater therapeutic effects than traditional salvage treatment could offer.

Background Immune-mediated necrotising myopathies are characterised clinically by the subacute onset of proximal limb weakness, accompanied by elevated creatinine kinase levels. They are distinguished from other myopathies by the absence of prominent infiltration of the muscle with inflammatory cells in the biopsies. Case presentation A 44-year-old man presented with upper extremity weakness and dysphagia. Laboratory tests included a creatinine kinase level of 4362 U/L (normal: 52-336 U/L). Rheumatological markers were all negative. A muscle biopsy showed multiple necrotic fibres with minimal inflammatory infiltration. One gram of methylprednisolone (IV) was given, followed by 1 mg/kg of methylprednisolone daily by the oral route. Intravenous immunoglobulin (0.4 mg/kg/day) was given for five days. Muscle weakness regressed and dysphagia disappeared with treatment. The patient remains well in the 23rd month of treatment, taking 5 mg/day prednisolone and monthly intravenous immunoglobulin. Conclusion Treatment of immune-mediated necrotising myopathy can be challenging as evidence-based therapeutic options are limited. It is generally accepted that early and extensive immunosuppression, including glucocorticoids as first-line agents, may be required.

Uropathogenic Escherichia coli (UPEC) is the most common cause of urinary tract infections. In this study, UPEC strains harboring hemolysin A (HlyA) did not induce programmed cell death pathways by the activation of caspases. Instead, the UPEC pore-forming toxin HlyA triggered an increase in mitochondrial Ca 2+ levels and manipulated mitochondrial dynamics by causing fragmentation of the mitochondrial network. Alterations in mitochondrial dynamics resulted in severe impairment of mitochondrial functions by loss of membrane potential, increase in reactive oxygen species production, and ATP depletion. Moreover, HlyA caused disruption of plasma membrane integrity that was accompanied by extracellular release of the danger-associated molecules high-mobility group box 1 (HMGB1) and histone 3 (H3). Our results indicate that UPEC induced programmed cell necrosis by irreversibly impairing mitochondrial function. This finding suggests a strategy devised by UPEC at the onset of infection to escape early innate immune response and silently propagate inside host cells.-Lu, Y., Rafiq, A., Zhang, Z., Aslani, F., Fijak, M., Lei, T., Wang, M., Kumar, S., Klug, J., Bergmann, M., Chakraborty, T., Meinhardt, A., Bhushan, S. Uropathogenic Escherichia coli virulence factor hemolysin A causes programmed cell necrosis by altering mitochondrial dynamics.

BACKGROUND Periodontal ligament stem cells (PDLSCs) possess characteristics of multi-potential differentiation and immuno-modulation, and PDLSCs-mediated periodontal tissue regeneration is regarded as a hopeful method for periodontitis treatment. Recent studies demonstrated that RIP3 and caspase8 regulate bacteria-induced innate immune response and programmed necrosis, which is also called necroptosis. This study aimed to determine the role of the RIP3/Caspase8 signal pathway on necroptosis of PDLSCs under the inflammatory microenvironment, both [i]in vitro[/i] and [i]in vivo[/i]. MATERIAL AND METHODS PDLSCs were cultured, and transmission electron microscopy and flow cytometry were used to detect necroptosis. PCR, ALP, and Alizarin Red S staining were used to assess the effect of necroptosis on osteogenesis differentiation of PDLSCs [i]in vitro[/i], while HE and Masson staining were taken after the nude mouse subcutaneous transplant experiment. RESULTS Our research indicates that RIP3/caspase8 can regulate the immune response of PDLSCs, and blockade of RIP3/caspase8 can protect the biological characteristics of the PDLSCs, effectively promoting periodontal tissue regeneration in the inflammatory microenvironment. CONCLUSIONS Inhibiting RIP3/caspase8 can effectively promote periodontal tissue regeneration in the inflammatory microenvironment.

Necroptosis is the best-described form of regulated necrosis at present, which is widely recognized as a component of caspase-independent cell death mediated by the concerted action of receptor-interacting protein kinase 1 (RIPK1) and receptor-interacting protein kinase 3 (RIPK3). Mixed-lineage kinase domain-like (MLKL) was phosphorylated by RIPK3 at the threonine 357 and serine 358 residues and then formed tetramers and translocated onto the plasma membrane, which destabilizes plasma membrane integrity leading to cell swelling and membrane rupture. Necroptosis is downstream of the tumor necrosis factor (TNF) receptor family, and also interaction with NOD-like receptor pyrin 3 (NLRP3) induced inflammasome activation. Multiple inhibitors of RIPK1 and MLKL have been developed to block the cascade of signal pathways for procedural necrosis and represent potential leads for drug development. In this review, we highlight recent progress in the study of roles for necroptosis in cerebral ischemic disease and discuss how these modifications delicately control necroptosis.

Necroptosis, a form of regulated necrotic cell death, is governed by RIP1/RIP3-mediated activation of MLKL. However, the signaling process leading to necroptotic death remains to be elucidated. In this study, we found that PUMA , a proapoptotic BH3-only Bcl-2 family member, is transcriptionally activated in an RIP3/MLKL-dependent manner following induction of necroptosis. The induction of PUMA, which is mediated by autocrine TNF-α and enhanced NF-κB activity, contributes to necroptotic death in RIP3-expressing cells with caspases inhibited. On induction, PUMA promotes the cytosolic release of mitochondrial DNA and activation of the DNA sensors DAI/Zbp1 and STING, leading to enhanced RIP3 and MLKL phosphorylation in a positive feedback loop. Furthermore, deletion of PUMA partially rescues necroptosis-mediated developmental defects in FADD -deficient embryos. Collectively, our results reveal a signal amplification mechanism mediated by PUMA and cytosolic DNA sensors that is involved in TNF-driven necroptotic death in vitro and in vivo., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)

Background: Prolonged sun exposure in high ambient temperatures has been recognized as a cause of thermal burns on the dorsal skin of dogs, termed dorsal thermal necrosis (DTN)., Hypotheses/objectives: To characterize the clinical presentation, histopathology and outcomes of 16 dogs diagnosed with DTN and to identify associated risk factors., Animals: Sixteen dogs diagnosed with DTN., Methods: Medical records from 2009 to 2016 were reviewed retrospectively. Inclusion criteria included: (i) historical solar exposure; (ii) dorsal burn injuries and (iii) histopathological findings consistent with DTN., Results: The majority of cases (15 of 16) occurred during warmer months (May-September) in the southwestern USA. Affected dogs had predominantly dark, short hair coats, whereas four of 16 dogs had lighter coat colours. Five dogs had naturally longer hair, but two hair coats had been recently clipped. Signs consistent with heat exhaustion or heatstroke were reported prior to the development of cutaneous lesions in four of 16 dogs. The most common skin lesions were alopecia, erythema, ulcerations, eschars/necrosis and crusts. Histological findings were consistent with other types of partial and full-thickness thermal burns, and included coagulation necrosis in the majority of cases. Most dogs were treated supportively with analgesics and antimicrobial therapies. The majority of DTN wounds healed via second intention, although surgery was performed on two dogs., Conclusions and Clinical Importance: Dorsal thermal necrosis should be considered as a differential diagnosis for dogs with dorsal cutaneous burns and a history of sun exposure in high external temperatures. Dogs with dark, short hair coats may be at an increased risk., (© 2018 ESVD and ACVD.)

Severe nerve injury such as axotomy induces neuron degeneration and death of surrounding glial cells. Using a crayfish stretch receptor that consists of a single mechanoreceptor neuron enveloped by satellite glia, we showed that axotomy not only mechanically injures glial cells at the transection location, but also induces necrosis or apoptosis of satellite glial cells remote from the transection site. We studied Ca 2+ role in spontaneous or axotomy-induced death of remote glial cells. Stretch receptors were isolated using the original technique that kept the neuron connected to the ventral cord ganglion (control preparations). Using Ca 2+ -sensitive fluorescence probe fluo-4, we showed Ca 2+ accumulation in neuronal perikarion and glial envelope. Ca 2+ gradually accumulated in glial cells after axotomy. In saline with triple Ca 2+ concentration the axotomy-induced apoptosis of glial cells increased, but spontaneous or axotomy-induced necrosis was unexpectedly reduced. Saline with 1/3[Ca 2+ ], oppositely, enhanced glial necrosis. Application of ionomycin, CdCl 2 , thapsigargin, and ryanodine showed the involvement of Ca 2+ influx through ionic channels in the plasma membrane, inhibition of endoplasmic reticulum Ca 2+ -ATPase, and Ca 2+ release from endoplasmic reticulum through ryanodine receptors in axotomy-induced glial necrosis. Apoptosis of glial cells surrounding axotomized neurons was promoted by ionomycin and thapsigargin. Possibly, other Ca 2+ sources such as penetration through the plasma membrane contributed to axotomy-induced apoptosis and necrosis of remote glial cells. Thus, modulating different pathways that maintain calcium homeostasis, one can modulate axotomy-induced death of glial cells remote from the transection site., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The osmotic demyelination syndrome (ODS) is a non-primary inflammatory disorder of the central nervous system myelin that is often associated with a precipitous rise of serum sodium concentration. To investigate the physiopathology of ODS in vivo, we generated a novel murine model based on the abrupt correction of chronic hyponatremia. Accordingly, ODS mice developed impairments in brainstem auditory evoked potentials and in grip strength. At 24 hr post-correction, oligodendrocyte markers (APC and Cx47) were downregulated, prior to any detectable demyelination. Oligodendrocytopathy was temporally and spatially correlated with the loss of astrocyte markers (ALDH1L1 and Cx43), and both with the brain areas that will develop demyelination. Oligodendrocytopathy and astrocytopathy were confirmed at the ultrastructural level and culminated with necroptotic cell death, as demonstrated by pMLKL immunoreactivity. At 48 hr post-correction, ODS brains contained pathognomonic demyelinating lesions in the pons, mesencephalon, thalamus and cortical regions. These damages were accompanied by blood-brain barrier (BBB) leakages. Expression levels of IL-1β, FasL, TNFRSF6 and LIF factors were significantly upregulated in the ODS lesions. Quiescent microglial cells type A acquired an activated type B morphology within 24 hr post-correction, and reached type D at 48 hr. In conclusion, this murine model of ODS reproduces the CNS demyelination observed in human pathology and indicates ambiguous causes that is regional vulnerability of oligodendrocytes and astrocytes, while it discards BBB disruption as a primary cause of demyelination. This study also raises new queries about the glial heterogeneity in susceptible brain regions as well as about the early microglial activation associated with ODS., (© 2017 Wiley Periodicals, Inc.)

The term acute tubular necrosis was thought to represent a misnomer derived from morphological studies of human necropsies and necrosis was thought to represent an unregulated passive form of cell death which was not amenable to therapeutic manipulation. Recent advances have improved our understanding of cell death in acute kidney injury. First, apoptosis results in cell loss, but does not trigger an inflammatory response. However, clumsy attempts at interfering with apoptosis (e.g. certain caspase inhibitors) may trigger necrosis and, thus, inflammation-mediated kidney injury. Second, and most revolutionary, the concept of regulated necrosis emerged. Several modalities of regulated necrosis were described, such as necroptosis, ferroptosis, pyroptosis and mitochondria permeability transition regulated necrosis. Similar to apoptosis, regulated necrosis is modulated by specific molecules that behave as therapeutic targets. Contrary to apoptosis, regulated necrosis may be extremely pro-inflammatory and, importantly for kidney transplantation, immunogenic. Furthermore, regulated necrosis may trigger synchronized necrosis, in which all cells within a given tubule die in a synchronized manner. We now review the different modalities of regulated necrosis, the evidence for a role in diverse forms of kidney injury and the new opportunities for therapeutic intervention., (Copyright © 2017 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: Reactive oxygen species (ROS) has a key role in the pathogenesis of sepsis. We wanted to evaluate ROS-associated lymphocyte necrosis and apoptosis., Materials and Methods: A total of 51 patients were included in the study, 29 in the patient group and 22 in the control group. Blood samples were taken from patients in the patient group during severe sepsis or septic shock, then again once they had recovered. Oxidative DNA damage was evaluated by 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels. Peripheral blood lymphocytes from patients were evaluated with a microscope immediately. The rate of apoptosis and necrosis of lymphocytes were evaluated according to the number of cells in the peripheral., Results: The level of 8-OHdG increased with severe sepsis or septic shock. There were significant differences between the pre- and post-treatment values for apoptotic cell frequency (4.21±3.15 vs. 3.82±3.07, P<0.05) and necrotic cell frequency (4.75±3.61 vs. 4.09±3.37, P<0.05). Apoptosis and necrosis was increased during severe sepsis and septic shock, and apoptosis increase also continued after recovery, but necrosis decreased following disease recovery. CONCLUSıONS: In patients with severe sepsis or septic shock, apoptosis and necrosis were increased along with increased 8-OHdG level., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Receptor interacting proteins (RIPs) are a group of threonine/serine protein kinases, which have relatively conserved kinase domains and different non-kinase domains, and are involved in physiological and pathological processes including innate immune response and inflammation. In recent years, many studies have shown that RIPs mediate cell necroptosis and triggers inflammatory responses by participating in the formation of necrotic complexes, and RIP1 and RIP3 are particularly closely related to cell necrosis. Cell necroptosis is a well-regulated way of cell death. The death signal that transmit through the TNF signaling pathway and the Toll-like receptor signaling pathway can recruit and phosphorylate mixed lineage kinase domain-like protein (MLKL), and eventually leading to disintegration and death of cells, and the release of cells intercellular material after cell disintegration can trigger an inflammatory reaction. This review mainly focuses on the major signaling pathways and molecular mechanisms that are involved in the mediation of necrosis and inflammation by RIPs. It also highlights the importance of RIPs in the development of inflammatory diseases and their potentials as therapeutic targets for inflammatory diseases.

Self-adherent elastic wrap dressings are a convenient option to manage pediatric hand and finger injuries. However, when improperly applied, they have the potential to cause devastating complications. We detail in this report 5 cases of dressing-induced ischemic injury to the hand in pediatric patients with a review of the literature. All patients were treated by the senior author between 2007 and 2015 and were retrospectively reviewed for initial injury, frequency of dressing changes, presence of pain, time to evaluation by the orthopedic hand team, treatment, and outcome. Patients' families were contacted for clinical updates and to obtain current photographs. Age at injury ranged from 11 months to 3 years with 2 girls and 3 boys. Only 1 of 5 patients complained of pain or discomfort during the onset of their ischemic injury. Treatment of the ischemic injury included local wound care without surgery in 3 cases (including sympathetic block in 1) and surgical intervention with partial or complete digital amputation in 2 cases. At final follow-up, 2 of the 5 patients reported currently being bothered by the appearance of the injured hand; however, none had persistent pain or difficulty using the hand. Through these examples, health care professionals can be educated on the potentially disastrous complications of improper dressing application in the pediatric population and can be encouraged to share this information with patients' families., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose., (Copyright © 2018 by the American Academy of Pediatrics.)

Is Oxygen Deficiency Always Harmful? Abstract. The role of the cardiovascular circulation is to supply tissue with oxygen and nutrients. Oxygen deficiency (hypoxia) is considered life-threatening, since cells die, either through apoptotic or necrotic processes. Tissue tries to counteract this by means of evolutionary signalling pathways, such as the nuclear hypoxia-inducible factor, which protects the tissue by promoting cell survival strategies and simultaneously intervening in angiogenesis, haematogenesis and metabolic processes. Recent findings indicate that these conserved signalling pathways can also function as therapeutic approaches in wound healing of bones and skin, as well as in the regeneration of tissues, e.g. in the liver, and in the hematopoietic system.

Case: A 47-year-old Caucasian woman spontaneously developed an isolated anterior compartment pressure of >100 mm Hg in the left leg. Despite fasciotomies, the musculature was nonviable and required debridement. Following Achilles tendon lengthening, a posterior tibial tendon (PTT) to anterior tibial tendon (ATT) transfer was supplemented with a flexor digitorum longus tendon transfer to the remaining PTT in order to prevent a flatfoot deformity while restoring active dorsiflexion., Conclusion: Preservation of the tendinous portion of the ATT during debridement allowed for transfer of the PTT to the ATT using a modified Pulvertaft transfer. This technique allowed early ambulation and restoration of active dorsiflexion, obviating the ongoing use of an ankle-foot orthosis.

Advances in neuroimaging have enabled the mapping of white matter connections across the entire brain, allowing for a more thorough examination of the extent of white matter disconnection after stroke. To assess how cortical disconnection contributes to motor impairments, we examined the relationship between structural brain connectivity and upper and lower extremity motor function in individuals with chronic stroke. Forty-three participants [mean age: 59.7 (±11.2) years; time poststroke: 64.4 (±58.8) months] underwent clinical motor assessments and MRI scanning. Nonparametric correlation analyses were performed to examine the relationship between structural connectivity amid a subsection of the motor network and upper/lower extremity motor function. Standard multiple linear regression analyses were performed to examine the relationship between cortical necrosis and disconnection of three main cortical areas of motor control [primary motor cortex (M1), premotor cortex (PMC), and supplementary motor area (SMA)] and motor function. Anatomical connectivity between ipsilesional M1/SMA and the (1) cerebral peduncle, (2) thalamus, and (3) red nucleus were significantly correlated with upper and lower extremity motor performance (P ≤ 0.003). M1-M1 interhemispheric connectivity was also significantly correlated with gross manual dexterity of the affected upper extremity (P = 0.001). Regression models with M1 lesion load and M1 disconnection (adjusted for time poststroke) explained a significant amount of variance in upper extremity motor performance (R 2  = 0.36-0.46) and gait speed (R 2  = 0.46), with M1 disconnection an independent predictor of motor performance. Cortical disconnection, especially of ipsilesional M1, could significantly contribute to variability seen in locomotor and upper extremity motor function and recovery in chronic stroke. Hum Brain Mapp 39:120-132, 2018. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

BACKGROUND The purpose of this study was to explore changes in cartilage matrix in early-stage femoral head necrosis (FHN). MATERIAL AND METHODS Femoral head samples of patients with early FHN were collected during total hip arthroplasty (THA), high-field 7.0T MRI scans were performed in vitro, and the average T2 values were calculated. Cartilage samples were obtained from the weight-bearing area (FHN group) and non-weight-bearing area (Control group), divided into 3 equal parts and used for biochemical analysis, histopathological staining, and gene expression analysis. RESULTS T2 mapping of the femoral head specimens showed that the density distribution of cartilage surface was not uniform, and the average T2 value increased unevenly. Histological staining demonstrated that the number of chondrocytes was significantly decreased and they were irregularly arranged, SO staining was lost, and collagen fiber arrangement was slightly more irregular on the cartilage surface in the FHN group. The biochemical results in the FHN group showed that the water content increased significantly and the DNA content decreased significantly, while no significant changes in GAG and total collagen contents were detected. Gene expression analysis in the FHN group showed that SOX9 expression was significantly down-regulated, while COL10A1 and RUNX2 expressions were significantly up-regulated. The expression of ACAN and COL2A1 were decreased and COL1A1 was increased, but there was no significant difference compared with the Control group. CONCLUSIONS Taken together, the results of this study suggest that patients with early-stage FHN tend to have cartilage matrix degeneration, which provides new ideas for studying the pathogenesis of FHN and selecting treatment strategies.

Fowl cholera resulting from infection with Pasteurella multocida causes huge economic losses in the poultry industry. Necrotic hepatitis is reported to be a significant lesion associated with fowl cholera in chickens. Clarifying the underlying molecular mechanism of hepatic injury caused by P. multocida infection is needed to develop new strategies to control fowl cholera. Pasteurella multocida Q (the standard reference strain) and P. multocida 1G1 (a clinical strain) were used to infect healthy laying hens. Clinical signs were observed and gross lesions in livers were observed postmortem. Histologic lesions and the localization and expression of protein molecules associated with necroptosis, apoptosis, and inflammation in hepatic tissues were examined by hematoxylin and eosin staining and immunohistochemistry. Western blot analysis was used to determine the expression of liver injury-related genes. Necroptotic molecules such as RIPK1 (receptor interaction protein kinases 1), RIPK3 (receptor interaction protein kinases 3), and MLKL (mixed lineage kinase domain-like protein) were observed by immunostaining primarily in the cytoplasm of hepatocytes within or around necrotic foci, and inflammatory mediators HMGB1 (high-mobility group box 1) and IL-6 (interleukin-6) were found in the cytoplasm of heterophils, monocytes/macrophages, and hepatic sinusoids. In addition, MMP9 (matrix metalloproteinase 9) and TIMP1 (tissue inhibitor of metalloproteinase 1) were observed in hepatic parenchymal cells, inflammatory cells, and interstitial spaces, whereas the apoptotic effector molecule caspase-3 (cysteine-containing aspartic proteolytic enzymes 3) was mainly found in hepatocytes. The expression of RIPK1, RIPK3, and MLKL was significantly higher in the infected chickens than in the controls. HMGB1 and IL-6 protein levels were also increased in infected chickens relative to those in controls. Both MMP9 and TIMP1 were highly expressed in infected chickens. In addition, caspase-3 protein levels were significantly elevated in infected chickens. Necroptosis, apoptosis, and inflammation played a significant role in hepatic injury caused by P. multocida.