Acute Insult Research Articles

Circular RNA circBNC2 inhibits epithelial cell G2-M arrest to prevent fibrotic maladaptive repair

The mechanisms underlying fibrogenic responses after injury are not well understood. Epithelial cell cycle arrest in G2/M after injury is a key checkpoint for determining wound-healing leading to either normal cell proliferation or fibrosis. Here, we identify a kidney- and liver-enriched circular RNA, circBNC2, which is abundantly expressed in normal renal tubular cells and hepatocytes but significantly downregulated after acute ischemic or toxic insult. Loss of circBNC2 is at least partially mediated by upregulation of DHX9. Gain- and loss-of-function studies, both in vitro and in vivo, demonstrate that circBNC2 acts as a negative regulator of cell G2/M arrest by encoding a protein that promotes formation of CDK1/cyclin B1 complexes. Restoring circBNC2 in experimentally-induced male mouse models of fibrotic kidney and liver, decreases G2/M arrested cell numbers with secretion of fibrotic factors, thereby mitigating extracellular matrix deposition and fibrosis. Decreased expression of circBNC2 and increased G2/M arrest of epithelial cells are recapitulated in human ischemic reperfusion injury (IRI)-induced chronic kidney disease and inflammation-induced liver fibrosis, highlighting the clinical relevance. These findings suggest that restoring circBNC2 might represent a potential strategy for therapeutic intervention in epithelial organ fibrosis.

Transport of the Proinflammatory Chemokines C-C Motif Chemokine Ligand 2 (MCP-1) and C-C Motif Chemokine Ligand 5 (RANTES) across the Intact Mouse Blood-Brain Barrier Is Inhibited by Heparin and Eprodisate and Increased with Systemic Inflammation.

One important function of the vascular blood-brain barrier (BBB) is to facilitate neuroimmune communication. The BBB fulfills this function, in part, through its ability to transport cytokines and chemokines. C-C motif chemokine receptor 2 (CCL2) (MCP-1) and C-C motif chemokine receptor 5 (CCL5) (RANTES) are proinflammatory chemokines that mediate neuroimmune responses to acute insults and aspects of brain injury and neurodegenerative diseases; however, a blood-to-brain transport system has not been evaluated for either chemokine in vivo. Therefore, we determined whether CCL2 and CCL5 in blood can cross the intact BBB and enter the brain. Using CD-1 mice, we found that 125I-labeled CCL2 and CCL5 crossed the BBB and entered the brain parenchyma. We next aimed to identify the mechanisms of 125I-CCL2 and 125I-CCL5 transport in an in situ brain perfusion model. We found that both heparin and eprodisate inhibited brain uptake of 125I-CCL2 and 125I-CCL5 in situ, whereas antagonists of their receptors, CCR2 or CCR5, respectively, did not, suggesting that heparan sulfates at the endothelial surface mediate BBB transport. Finally, we showed that CCL2 and CCL5 transport across the BBB increased following a single injection of 0.3 mg/kg lipopolysaccharide. These data demonstrate that CCL2 and CCL5 in the brain can derive, in part, from the circulation, especially during systemic inflammation. Further, binding to the BBB-associated heparan sulfate is a mechanism by which both chemokines can cross the intact BBB, highlighting a novel therapeutic target for treating neuroinflammation. SIGNIFICANCE STATEMENT: Our work demonstrates that C-C motif chemokine ligand 2 (CCL2) and C-C motif chemokine ligand 5 (CCL5) can cross the intact blood-brain barrier and that transport is robustly increased during inflammation. These data suggest that circulating CCL2 and CCL5 can contribute to brain levels of each chemokine. We further show that the transport of both chemokines is inhibited by heparin and eprodisate, suggesting that CCL2/CCL5-heparan sulfate interactions could be therapeutically targeted to limit accumulation of these chemokines in the brain.

Radiation-Induced Acute Cardiotoxicity in Women with Left Sided Breast Cancer: Results from a Phase II Prospective Clinical Trial

<h3>Purpose/Objective(s)</h3> Women with left sided breast cancer (BC) who receive adjuvant radiotherapy (RT) have increased risk of subsequent cardiac events, which may be mitigated by maintaining mean heart dose (MHD) below a threshold of 3 Gy. We hypothesized that early MRI evaluation of cardiac functional changes can identify acute cardiac insult and predict for the risk of long-term cardiac complications. Here we report the findings of a phase II prospective clinical trial evaluating RT-related LV structure and function using cardiac MRI in women with left sided BC treated with adjuvant RT. <h3>Materials/Methods</h3> Patients with left sided BC were enrolled into a single institutional phase II study. After informed consent, patients were allocated for breast RT with free breathing (FB) or with deep inspiratory breath hold (DIBH) delivery, if the predicted MHD was ≤3 Gy (≤ 5 Gy, if also regional nodal RT) or > 3 Gy (> 5 Gy, if regional nodal RT), respectively, on initial FB planning. Cardiac MRI was performed at baseline (pre-RT), and at 16 and 52 weeks. Cardiac toxicity was defined as change in the indexed LV end diastolic volume (LVEDVi), LV ejection fraction (LVEF), indexed LV end systolic volume (LVESVi) and indexed LV mass (LV MASSi). Estimation of multiple serum cardiac biomarkers were also done at the three time points. Continuous variables were expressed as mean ± standard deviation, and ANOVA analysis was used to identify correlation between changes in cardiac parameters from baseline to 16 and 52 weeks, when compared to cardiac radiation dosimetric data. <h3>Results</h3> Of the 69 participants, 25 received RT with FB technique. 44 received RT with DIBH, of which 23 also had received adjuvant chemotherapy (CT) prior to RT. For the FB, DIBH (no CT), and DIBH (with CT) cohorts, MHD was 1.70 ± 0.93 Gy, 1.93 ± 1.30 Gy, and 2.26 ± 1.15 Gy and mean LV dose was 2.47 ± 1.48 Gy, 3.18 ± 1.93 Gy, and 3.23 ± 1.82 Gy, respectively. Evaluation of LVEDVi, LVEF, LVESVi, and LV MASSi showed no statistical difference between the 3 treatment arms. No statistical correlation was noted between LVEF changes (≥ 5% and ≥ 10% from baseline) and the cardiac dosimetric data; all p values > 0.1. Prior CT did not measurably impact cardiac function. <h3>Conclusion</h3> In this prospective study, no significant post-RT cardiac events were demonstrable by functional imaging. This supports the significance of maintaining MHD ≤ 3 Gy to minimize or prevent RT related cardiac toxicity in women with left sided BC. Our observation warrants further investigation in a large prospective setting to evaluate late cardiac events. Analysis of serum cardiac biomarkers is currently ongoing.

Dental Pulp-Derived Stem Cells Preserve Astrocyte Health During Induced Gliosis by Modulating Mitochondrial Activity and Functions.

Astrocytes have been implicated in the onset and complication of various central nervous system (CNS) injuries and disorders. Uncontrolled astrogliosis (gliosis), while a necessary process for recovery after CNS trauma, also causes impairments in CNS performance and functions. The ability to preserve astrocyte health and better regulate the gliosis process could play a major role in controlling damage in the aftermath of acute insults and during chronic dysfunction. Here in, we demonstrate the ability of dental pulp-derived stem cells (DPSCs) in protecting the health of astrocytes during induced gliosis. First of all, we have characterized the expression of genes in primary astrocytes that are relevant to the pathological conditions of CNS by inducing gliosis. Subsequently, we found that astrocytes co-cultured with DPSCs reduced ROS production, NRF2 and GCLM expressions, mitochondrial membrane potential, and mitochondrial functions compared to the astrocytes that were not co-cultured with DPSCs in gliosis condition. In addition, hyperactive autophagy was also decreased in astrocytes that were co-cultured with DPSCs compared to the astrocytes that were not co-cultured with DPSCs during gliosis. This reversal and mitigation of gliosis in astrocytes were partly due to induction of neurogenesis in DPSCs through enhanced expressions of the neuronal genes like GFAP, NeuN, and Synapsin in DPSCs and by secretion of higher amounts of neurotropic factors, such as BDNF, GDNF, and TIMP-2. Protein-Protein docking analysis suggested that BDNF and GDNF can bind with CSPG4 and block the downstream signaling. Together these findings demonstrate novel functions of DPSCs to preserve astrocyte health during gliosis.

S1396 Response-Guided Ascites Mobilization in Patients of Acute on Chronic Liver Failure (ACLF) With Acute Kidney Injury Treated With Slow Albumin, Furosemide and Vasoconstrictor Therapy (SAFI+T) versus Standard Treatment

Introduction: Acute-on-chronic liver failure (ACLF) with increasing organ failure is associated with poor outcome. Severely deranged systemic hemodynamic and decreased effective arterial blood volume contributes to tissue damage and organ failure. Response guided therapy with albumin, vasoconstrictors and furosemide may help overcome effective hypovolemia improve diuresis and impact survival. Methods: In observation cohort, 56 patients with ACLF (CANONIC criteria) complicated with AKI ( S.Cr ³ 1.5, >50% increased S.cr from baseline), ascites (≥ Grade II) were enrolled. 30 patients (GROUP I) received response guided(Urine sodium >80mmol/day) slow albumin-furosemide infusion ± terlipressin (SAFI±T), while 26 patients (GROUP II) received standard medical therapy. 28-day survival, ascites mobilization (nil or grade 1), reversal of AKI and adverse events were noted. Laboratory evidences for improvement in various pathophysiological alterations; endotoxemia, cytokine storm, neutrophil dysfunction and secondary infections, following SAFI±T were evaluated. Results: Alcohol and sepsis were the commonest etiologies for chronic and acute insult respectively. Ascites was completely mobilized in 18/30 (60%) patients in Group I (SAFI±T) and 7/26 (26.9%) in Group II (p< 0.05). At 28 days the survival analysis showed, Group I 23/30 (76.4%) and Group II 14/26 (53.8%) (P=< 0.05). There was a lower incidence of hospital acquired infection in Group I of 6.7% vs 38.4% in Group II (p=0.05) and the same was reflected in serum endotoxin and pro-inflammatory cytokine levels; IL-6 and IL-1b showed significant reduction in Group I. Serum endotoxin and TNF-a level increased in Group II despite SMT while it showed significant fall in SAFI+T arm post treatment. Renal artery resistive index was significantly lower after SAFI(T) therapy (0.84 to 0.72) (p< 0.05) as similar trend emulated in UNa level. Conclusion: Patients with ACLF treated with SAFI+T protocol had higher natriuresis, enhanced urine output, complete ascites removal, and improved renal function with a faster mean duration of treatment and better 28-day survival. An in-hospital infection rate was lower. Ascites mobilization was associated with improvement in gut permeability, endotoxemia, pro-inflammatory cytokines, and NETosis in the SAFI+T cohort, showing an association between ascites mobilization and improved pathophysiologic dysfunctions.

Longitudinal lung function in urban firefighters: A group-based multi-trajectory modelling approach.

Urban firefighters are routinely exposed to both physical and chemical hazards that can negatively impact lung health, but it is unclear if firefighters experience accelerated decline in spirometry parameters due to chronic exposure and acute insults. This study aimed to describe sub-groups of firefighters with differing spirometry trajectories and examine the relationship between the identified trajectories and demographic, lifestyle and occupational characteristics. Data from six waves of the Respiratory Function Measurement and Surveillance for South Australian Metropolitan Fire Service Study (2007-2019) were used to identify spirometry parameter z-score trajectories, using group-based multi-trajectory modelling (GBMTM). Analysis of variance and chi-square statistics were used to assess trajectory group differences in baseline self-reported demographic, lifestyle and occupational characteristics. In the 669 included firefighters, we identified five trajectories for the combination of Forced Expiratory Volume in the first second z-score (FEV1 z), Forced Vital Capacity z-score (FVCz) and the ratio of FEV1 and FVC z-score (FEV1 /FVCz). There were three stable trajectories of low, average and very high lung function and two declining trajectories of average and high lung function. Analysis of subgroup characteristics revealed no significant differences between expected and actual group proportions for the occupational characteristics of years of service and respiratory protection use. Significant differences were seen in respiratory health and body mass index. GBMTM defined distinct, plausible spirometry trajectory sub-groups. Firefighter longitudinal spirometry trajectory group membership was associated with BMI and respiratory disease or symptoms but not with self-reported smoking history or occupational factors.

Electrochemically induced in vitro focal hypoxia in human neurons.

Focalised hypoxia is widely prevalent in diseases such as stroke, cardiac arrest, and dementia. While in some cases hypoxia improves cellular functions, it mostly induces or exacerbates pathological changes. The lack of methodologies that can simulate focal acute hypoxia, in either animal or cell culture, impedes our understanding of the cellular consequences of hypoxia. To address this gap, an electrochemical localised oxygen scavenging system (eLOS), is reported, providing an innovative platform for spatiotemporal in vitro hypoxia modulation. The electrochemical system is modelled showing O2 flux patterns and localised O2 scavenging and hypoxia regions, as a function of distance from the electrode and surrounding flux barriers, allowing an effective focal hypoxia tool to be designed for in vitro cell culture study. O2 concentration is reduced in an electrochemically defined targeted area from normoxia to hypoxia in about 6 min depending on the O2-flux boundaries. As a result, a cell culture-well was designed, where localised O2 scavenging could be induced. The impact of localised hypoxia was demonstrated on human neural progenitor cells (hNPCs) and it was shown that miniature focal hypoxic insults can be induced, that evoke time-dependent HIF-1α transcription factor accumulation. This transcription is “patterned” across the culture according to the electrochemically induced spatiotemporal hypoxia gradient. A basic lacunar infarct model was also developed through the application of eLOS in a purpose designed microfluidic device. Miniature focal hypoxic insults were induced in cellular processes of fully oxygenated cell bodies, such as the axons of human cortical neurons. The results demonstrate experimentally that localised axonal hypoxic stress can lead to significant increase of neuronal death, despite the neurons remaining at normoxia. This suggests that focal hypoxic insult to axons alone is sufficient to impact surrounding neurons and may provide an in vitro model to study the impact of microinfarcts occurring in the deep cerebral white matter, as well as providing a promising tool for wider understanding of acute hypoxic insults with potential to uncover its pathophysiology in multiple diseases.

Development and in vivo validation of small interfering RNAs targeting NOX3 to prevent sensorineural hearing loss.

The reactive oxygen species (ROS)-generating enzyme NOX3 has recently been implicated in the pathophysiology of several acquired forms of sensorineural hearing loss, including cisplatin-, noise- and age-related hearing loss. NOX3 is highly and specifically expressed in the inner ear and therefore represents an attractive target for specific intervention aiming at otoprotection. Despite the strong rationale to inhibit NOX3, there is currently no specific pharmacological inhibitor available. Molecular therapy may represent a powerful alternative. In this study, we developed and tested a collection of small interfering (si) RNA constructs to establish a proof of concept of NOX3 inhibition through local delivery in the mouse inner ear. The inhibitory potential of 10 different siRNA constructs was first assessed in three different cells lines expressing the NOX3 complex. Efficacy of the most promising siRNA construct to knock-down NOX3 was then further assessed in vivo, comparing middle ear delivery and direct intracochlear delivery through the posterior semi-circular canal. While hearing was completely preserved through the intervention, a significant downregulation of NOX3 expression in the mouse inner ear and particularly in the spiral ganglion area at clinically relevant levels (>60%) was observed 48 h after treatment. In contrast to successful intracochlear delivery, middle ear administration of siRNA failed to significantly inhibit Nox3 mRNA expression. In conclusion, intracochlear delivery of NOX3-siRNAs induces a robust temporal NOX3 downregulation, which could be of relevance to prevent predictable acute insults such as cisplatin chemotherapy-mediated ototoxicity and other forms of acquired hearing loss, including post-prevention of noise-induced hearing loss immediately after trauma. Successful translation of our concept into an eventual clinical use in humans will depend on the development of atraumatic and efficient delivery routes into the cochlea without a risk to induce hearing loss through the intervention.

Time and age dependent regulation of neuroinflammation in a rat model of mesial temporal lobe epilepsy: Correlation with human data.

Acute brain insults trigger diverse cellular and signaling responses and often precipitate epilepsy. The cellular, molecular and signaling events relevant to the emergence of the epileptic brain, however, remain poorly understood. These multiplex structural and functional alterations tend also to be opposing - some homeostatic and reparative while others disruptive; some associated with growth and proliferation while others, with cell death. To differentiate pathological from protective consequences, we compared seizure-induced changes in gene expression hours and days following kainic acid (KA)-induced status epilepticus (SE) in postnatal day (P) 30 and P15 rats by capitalizing on age-dependent differential physiologic responses to KA-SE; only mature rats, not immature rats, have been shown to develop spontaneous recurrent seizures after KA-SE. To correlate gene expression profiles in epileptic rats with epilepsy patients and demonstrate the clinical relevance of our findings, we performed gene analysis on four patient samples obtained from temporal lobectomy and compared to four control brains from NICHD Brain Bank. Pro-inflammatory gene expressions were at higher magnitudes and more sustained in P30. The inflammatory response was driven by the cytokines IL-1β, IL-6, and IL-18 in the acute period up to 72 h and by IL-18 in the subacute period through the 10-day time point. In addition, a panoply of other immune system genes was upregulated, including chemokines, glia markers and adhesion molecules. Genes associated with the mitogen activated protein kinase (MAPK) pathways comprised the largest functional group identified. Through the integration of multiple ontological databases, we analyzed genes belonging to 13 separate pathways linked to Classical MAPK ERK, as well as stress activated protein kinases (SAPKs) p38 and JNK. Interestingly, genes belonging to the Classical MAPK pathways were mostly transiently activated within the first 24 h, while genes in the SAPK pathways had divergent time courses of expression, showing sustained activation only in P30. Genes in P30 also had different regulatory functions than in P15: P30 animals showed marked increases in positive regulators of transcription, of signaling pathways as well as of MAPKKK cascades. Many of the same inflammation-related genes as in epileptic rats were significantly upregulated in human hippocampus, higher than in lateral temporal neocortex. They included glia-associated genes, cytokines, chemokines and adhesion molecules and MAPK pathway genes. Uniquely expressed in human hippocampus were adaptive immune system genes including immune receptors CDs and MHC II HLAs. In the brain, many immune molecules have additional roles in synaptic plasticity and the promotion of neurite outgrowth. We propose that persistent changes in inflammatory gene expression after SE leads not only to structural damage but also to aberrant synaptogenesis that may lead to epileptogenesis. Furthermore, the sustained pattern of inflammatory genes upregulated in the epileptic mature brain was distinct from that of the immature brain that show transient changes and are resistant to cell death and neuropathologic changes. Our data suggest that the epileptogenic process may be a result of failed cellular signaling mechanisms, where insults overwhelm the system beyond a homeostatic threshold.

Galectin-3 critically mediates the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting pyroptosis but not necroptosis signalling

We previously documented that M2-like macrophages exert a hepatoprotective effect in acute-on-chronic liver failure (ACLF) by inhibiting necroptosis signalling. Nevertheless, the molecular mechanism behind this hepatoprotection still needs to be further dissected. Galectin-3 (GAL3) has been reported to be critically involved in the pathogenesis of multiple liver diseases, whereas the potential role of GAL3 in ACLF remains to be explored. Herein, we hypothesised that GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting necroptosis. To test this hypothesis, we first assessed the expression of GAL3 in control and fibrotic mice with or without acute insult. Second, loss- and gain-of-function experiments of GAL3 were performed. Third, the correlation between GAL3 and M2-like macrophage activation was analysed, and the potential role of GAL3 in M2-like macrophage-conferred hepatoprotection was confirmed. Finally, the molecular mechanism underlying GAL3-mediated hepatoprotection was dissected. GAL3 was found to be obviously upregulated in fibrotic mice with or without acute insult but not in acutely injured mice. Depletion of GAL3 aggravated hepatic damage in fibrotic mice upon insult. Conversely, adoptive transfer of GAL3 provided normal mice enhanced resistance against acute insult. The expression of GAL3 is closely correlated with M2-like macrophage activation. Through adoptive transfer and depletion experiments, M2-like macrophages were verified to act as a major source of GAL3. Importantly, GAL3 was confirmed to hold a pivotal place in the hepatoprotection conferred by M2-like macrophages through loss- and gain-of-function experiments. Unexpectedly, the depletion and adoptive transfer of GAL3 resulted in significant differences in the expression levels of pyroptosis but not necroptosis signalling molecules. Taken together, GAL3 plays a pivotal role in the hepatoprotection conferred by M2-like macrophages in ACLF by inhibiting pyroptosis but not necroptosis signalling. Our findings provide novel insights into the pathogenesis and therapy of ACLF.

Region-Specific Vulnerability of the Amygdala to Injury-Induced Spreading Depolarization.

Spreading depolarization (SD), a self-propagated wave of transient depolarization, regularly occurs in the cortex after acute brain insults and is now referred as an important diagnostic and therapeutic target in patients with acute brain injury. Here, we show that the amygdala, the limbic structure responsible for post-injury neuropsychological symptoms, exhibits strong regional heterogeneity in vulnerability to SD with high susceptibility of its basolateral (BLA) region and resilience of its centromedial (CMA) region to triggering SD by acute focal damage. The BLA micro-injury elicited SD twice as often compared with identical injury of the CMA region (71% vs. 33%). Spatiotemporal features of SDs triggered in the amygdala indicated diverse patterns of the SD propagation to the cortex. Our results suggest that even relatively small cerebral structures can exhibit regional gradients in their susceptibility to SD and the heterogeneity may contribute to the generation of complex SD patterns in the injured brain.

Acute Methylglyoxal-Induced Damage in Blood-Brain Barrier and Hippocampal Tissue.

Methylglyoxal (MG) is a reactive dicarbonyl compound formed mostly via the glycolytic pathway. Elevated blood glucose levels can cause MG accumulation in plasma and cerebrospinal fluid in patients with diabetes mellitus and Alzheimer's disease. Under these disease conditions, the high reactivity of MG leads to modification of proteins and other biomolecules, generating advanced glycation end products (AGEs), which are considered mediators in neurodegenerative diseases. We investigated the integrity of the blood-brain barrier (BBB) and astrocyte response in the hippocampus to acute insult induced by MG when it was intracerebroventricularly administered to rats. Seventy-two hours later, BBB integrity was lost, as assessed by the entry of Evans dye into the brain tissue and albumin in the cerebrospinal fluid, and a decrease in aquaporin-4 and connexin-43 in the hippocampal tissue. MG did not induce changes in the hippocampal contents of RAGE in this short interval, but decreased the expression of S100B, an astrocyte-secreted protein that binds RAGE. The expression of two important transcription factors of the antioxidant response, NF-κB and Nrf2, was unchanged. However, hemeoxigenase-1 was upregulated in the MG-treated group. These data corroborate the idea that hippocampal cells are targets of MG toxicity and that BBB dysfunction and specific glial alterations induced by this compound may contribute to the behavioral and cognitive alterations observed in these animals.

Microglia subtypes show substrate- and time-dependent phagocytosis preferences and phenotype plasticity.

Microglia are phagocytosis-competent CNS cells comprising a spectrum of subtypes with beneficial and/or detrimental functions in acute and chronic neurodegenerative disorders. The heterogeneity of microglia suggests differences in phagocytic activity and phenotype plasticity between microglia subtypes. To study these issues, primary murine glial cultures were cultivated in the presence of serum, different growth factors and cytokines to obtain M0-like, M1-like, and M2-like microglia as confirmed by morphology, M1/M2 gene marker expression, and nitric oxide assay. Single-cell analysis after 3 hours of phagocytosis of E.coli particles or IgG-opsonized beads showed equal internalization by M0-like microglia, whereas M1-like microglia preferably internalized E.coli particles and M2-like microglia preferably internalized IgG beads, suggesting subtype-specific preferences for different phagocytosis substrates. Time-lapse live-cells imaging over 16 hours revealed further differences between microglia subtypes in phagocytosis preference and internalization dynamics. M0- and, more efficiently, M1-like microglia continuously internalized E.coli particles for 16 hours, whereas M2-like microglia discontinued internalization after approximately 8 hours. IgG beads were continuously internalized by M0- and M1-like microglia but strikingly less by M2-like microglia. M2-like microglia initially showed continuous internalization similar to M0-like microglia but again discontinuation of internalization after 8 hours suggesting that the time of substrate exposure differently affect microglia subtypes. After prolonged exposure to E.coli particles or IgG beads for 5 days all microglia subtypes showed increased internalization of E.coli particles compared to IgG beads, increased nitric oxide release and up-regulation of M1 gene markers, irrespectively of the phagocytosis substrate, suggesting phenotype plasticity. In summary, microglia subtypes show substrate- and time-dependent phagocytosis preferences and phenotype plasticity. The results suggest that prolonged phagocytosis substrate exposure enhances M1-like profiles and M2-M1 repolarization of microglia. Similar processes may also take place in conditions of acute and chronic brain insults when microglia encounter different types of phagocytic substrates.

Exendin-4 Exacerbates Burn-Induced Mortality in Mice by Switching to Th2 Response

IntroductionTo determine if Exendin-4 could be a therapeutic agent for burn-induced hyperglycemia. Materials and methodsMale Balb/c mice received a bolus of Exendin-4 intraperitoneally immediately after 15% total body surface area scald injury. Tail glucose levels were recorded and T-cell functions were analyzed at 4 h and 24 h postburn (pb). Pancreatic pathology was observed consecutively. The secretions of cytokines were detected in serum, spleen, and lung. Apoptosis of splenic CD3+ T-cells was examined by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling and flow cytometry. ResultsAlthough Exendin-4 could attenuate burn-induced hyperglycemia in mice at 4 h pb, it accelerated their survival dose dependently with progressive depletion of splenocyte number. T-cell function underwent two-phasic changes following Exendin-4 treatment. Compared to placebo mice, T-cell from Exendin-4–treated mice was manifested with increased proliferation, while decreased IL-2 secretion and lower ratio of IL-4/IFN-γ at 4 h pb. However, at 24 h pb, it showed decreased proliferation, while increased IL-2 secretion and higher ratio of IL-4/IFN-γ. Exendin-4 could elicit higher circulating IL-6 and IL-10 levels at 4 h pb, which were pronounced in the lung at 24 h pb. In the meanwhile, severe inflammation could be found in the pancreas. At 24 h pb, the numbers of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling or caspase-3 positive cells and the apoptosis of CD3+ T-cells were significantly increased in the spleens of Exendin-4 mice relative to placebo mice. ConclusionsThese data support a pathogenic role of Exendin-4 signaling during thermal injury, warning against its clinical application in acute insults.

The role of inflammation in hematopoiesis and bone marrow failure: What can we learn from mouse models?

Hematopoiesis is a remarkable system that plays an important role in not only immune cell function, but also in nutrient transport, hemostasis and wound healing among other functions. Under inflammatory conditions, steady-state hematopoiesis switches to emergency myelopoiesis to give rise to the effector cell types necessary to fight the acute insult. Sustained or aberrant exposure to inflammatory signals has detrimental effects on the hematopoietic system, leading to increased proliferation, DNA damage, different forms of cell death (i.e., apoptosis, pyroptosis and necroptosis) and bone marrow microenvironment modifications. Together, all these changes can cause premature loss of hematopoiesis function. Especially in individuals with inherited bone marrow failure syndromes or immune-mediated aplastic anemia, chronic inflammatory signals may thus aggravate cytopenias and accelerate disease progression. However, the understanding of the inflammation roles in bone marrow failure remains limited. In this review, we summarize the different mechanisms found in mouse models regarding to inflammatory bone marrow failure and discuss implications for future research and clinical practice.

Reversibility of acute-on-chronic liver failure syndrome in hepatitis B virus-infected patients with and without prior decompensation.

Acute-on-chronic liver failure (ACLF) is a severe clinical syndrome associated with high short-term mortality and reversibility. This study aimed to compare the characteristics of survival and reversibility in hepatitis B virus (HBV)-related ACLF (HBV-ACLF) patients with and without previous decompensation. Overall, 1044 patients who fulfilled the acute hepatic insult criteria of the APASL-ACLF Research Consortium (AARC) definition were enrolled from a prospectively established cohort of HBV-related liver failure patients. These patients were divided into the AARC ACLF group and the non-AARC ACLF group according to prior decompensation. Mortality, reversibility of ACLF syndrome, and predicted factors associated with reversibility were evaluated. Liver transplantation-free mortality of the AARC ACLF group was significantly lower than that of the non-AARC ACLF group (28 days: 28.2% vs. 40.3%, p=.012; 90 days: 41.7% vs. 65.4%, p &lt; .001). The 5-year cumulative reversal rates of ACLF syndrome were 88.0% (374/425) and 66.0% (31/47) in the AARC and non-AARC ACLF groups, respectively, (p=.039). Following reversibility of ACLF syndrome, 340/374 (90.9%) and 21/31 (67.7%) patients in the AARC and non-AARC ACLF groups, respectively, maintained a stable status within 5 years. Although prior decompensation indicated poor reversibility of ACLF syndrome, HBV-infected patients with prior decompensation who fulfilled the acute hepatic insult criteria of the AARC definition showed favourable reversibility and maintained a stable status after receiving nucleoside analogues. The AARC ACLF definition identified HBV-ACLF as a distinct syndrome with good reversibility. HBV-infected patients with prior decompensation could be included in the AARC ACLF management.

Cardiovascular risk factors in a healthy population in the Croatian centre for cardiac rehabilitation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction According to the statistics of the WHO, cardiovascular diseases (CVD) are the leading cause of death. The problem of CVD is the fact that they do not give the right symptoms, and often lead to personal or public health problems. The first signs of CVD may be an acute myocardial infarction (AMI) or cerebrovascular insult (CVI) and it is important that the cause of them is a combination of risk factors (RF) that we can influence. High cardiovascular risk, due to the presence of one or more RF, requires early intervention with the aim of timely prevention of possible new complications. Purpose The aim of the retrospective study was to determine the prevalence of cardiovascular RF in persons who underwent preventive examinations at our Clinic for Treatment, Prevention and Rehabilitation of CVD. Methods The study included 100 respondents aged between 30 and 60y. When collecting and presenting data, the privacy and identity of the respondents are protected. For the purposes of the research, the data of medical documentation were used. The parameters used for the study were age, sex, height, weight, body mass index, abdominal thickness, arterial pressure values, blood sugar, ergometric and spirometry findings. For each respondent, daily life habits such as alcohol and smoking consumption, and levels of physical activity were recorded. Microsoft Excel and Statistics are used for data processing. Results According to the analysis of the obtained data, an equal number of men and women participated in the research (average age 47y). Anthropometric testing yielded a mean BMI for men and women which tells us that 44% of respondents are overweight and 21% are obese. Prior to the examination, 20% of respondents were diagnosed with arterial hypertension (AH), arrhythmia, hyperlipoproteinemia and diabetes. Only 2% of the subjects had elevated blood glucose values. Spirometric findings in all subjects were correct, while ergometric testing showed a decrease in values in as many as 75% of subjects. The control of daily living habits determined the enjoyment of tobacco products in 32% and alcohol in 10% of respondents. A worrying fact is that only 5% of respondents engage in some physical activity. In addition, new diagnoses are hyperlipoproteinemia IIa (40%), hyperlipoproteinemia IIb (16%), AH (13%), hyperlipidemia (6%), arrhythmia (4%), diabetes (2%), triglyceridemia (2%), ischemic heart disease (1%), carotid artery stenosis (1%). Conclusions The study found an increased incidence of cardiovascular RF in people who are not older. New diagnoses suggest a change in life habits towards eliminating the present cardiovascular RF in order to prevent possible cardiovascular incidents. It is through this organized, systematic and regular prevention that cardiovascular diseases are reduced to a significant level.

Role of duplex-guided infragenicular angioplasty in saving limbs

Background/aim Critical limb ischemia (CLI) is known as ischemic rest pain at rest or tissue loss with peripheral arterial disease. Endovascular intervention has many advantages than surgical bypasses and it is used frequently with fragile patients, at the same time, it has many adverse effects for both surgeon and patient such as radiation effect for both and renal-induced nephropathy for the patient. Worldwide duplex-guided infragenicular angioplasty is a new method that has been started to emerge and to be a common technique in such patients, That is why the present study aims to assess the feasibility and efficacy of duplex-guided infragenicular angioplasty to save limbs and to detect if it is applicable or not. Patients and methods Twenty CLI patients were admitted to the vascular unit from 2015 to 2017 in Al-Zahraa University Hospital, Al-Azhar University, Cairo, Egypt. We included patients with good femoral pulse and significant infragenicular lesions. We excluded those with proximal outflow lesions and with acute embolic or thrombotic insults. Percutanous transluminal angioplasty was done to all the patients through ipsilateral femoral access by using 0.014 and 0.018 wires 4 F catheters and low-profile balloons, then we followed them clinically and with duplex ultrasound at 1, 3, 6, and 12 months with calculating the hemodynamic studies. Results The present study enrolled 20 patients, six (30%) of them are females and 14 (70%) males, with mean age of 59.2. The clinical history of smokers, cardiac, diabetics, renal, and hypertensive were 65, 60, 50, 85, and 80%, respectively. Technical success was 90%. Groin hematoma, distal thrombosis, and vessel perforation were technical complications, with 5% for each. Optimal procedural success was achieved in 70%, of suboptimal in 20%, and then we failed in 10%. Rest paint completely disappeared from 75% of patients. Sixteen limbs were saved postintervention, Kaplan–Meier curve showed 70% survival rate at 6 months, while at 9 months, the drop occurred to be 28%, which was still to be the percent at 12 months. Conclusion Modern duplex ultrasound can be used to map the arterial disease and to show guide wires, sheaths, balloons, and stents for the treatment of infragenicular arterial lesions. Also, it seems to be safe, easy and effective technique, a bedside procedure, and cost-effective as well. It has a crucial role in saving limbs for CLI patients.

Neutrophil Respiratory Burst: an immunological indicator of post stroke infection

Stroke is long known to be followed by a series of immunosuppressive events, and infections might be a cause of death after an acute insult of stroke. The aim of our work was to assess the percentage of neutrophils showing spontaneous oxidative burst in patients with acute ischemic stroke. The study included 30 patients with acute cerebral infarction subjected to the following: magnetic resonance imaging of the brain immediately on admission, and blood sampling on day one of admission (baseline) and after 3 days of admission. Blood samples were used for the assessment of: differential leucocyte count and percentage of neutrophils showing spontaneous oxidative burst, performed by flow cytometry. Thirty age and gender matched controls were also recruited. Neutrophil respiratory burst percentage was significantly lower in stroke patients in comparison to controls (P < 0.001), and stroke patients had significantly lower neutrophil respiratory burst percent on day 3 of admission compared to the baseline (P < 0.001). Stroke-induced immune alterations including impairment of the first-line defense performed by neutrophils against bacteria. The hypothesis that these changes enhance susceptibility to acquired infections is supported by our observation that oxidative burst in neutrophils was more impaired in patients with stroke who exhibited subsequent stroke-associated infections.

Marine-derived n-3 fatty acids therapy for stroke.

Marine-derived n-3 fatty acids therapy for stroke.