Interleukin-17/interleukin-17 receptor axis elicits intestinal neutrophil migration, restrains gut dysbiosis and lipopolysaccharide translocation in high-fat diet-induced metabolic syndrome model.

Sound evidence supports a role for interleukin-17 (IL-17) -producing γδ T cells and IL-17-producing helper T (Th17) cells in intestinal homeostasis, especially in intestinal barrier integrity. In the present study, we aimed to evaluate the role of IL-17 cytokine in the regulation of intestinal immunity and obesity-induced metabolic syndrome (MetS) in an experimental murine model. C57BL/6 wild-type (WT) mice and mice lacking the IL-17 cytokine receptor (IL-17RA-/- ) were fed either a control diet (CD) or a high-fat diet (HFD) for 9 weeks. Our data demonstrate that IL-17RA-/- mice are protected against obesity, but develop hyperglycemia, hyperinsulinemia and insulin resistance. In parallel, HFD-fed IL-17RA-/- mice display intense inflammation in the ileum compared with WT mice on the HFD. IL-17RA-/- mice fed the HFD exhibit impaired neutrophil migration to the intestinal mucosa and reduced gene expression of the CXCL-1 chemokine and CXCR-2 receptor in the ileum. Interestingly, the populations of neutrophils (CD11b+  Ly6G+ ) and anti-inflammatory macrophages (CD11b+  CX3CR1+ ) are increased in the mesenteric lymph nodes of these mice. IL-17RA-/- mice on the HFD also display increased commensal bacterial translocation into the bloodstream and elevated lipopolysaccharide (LPS) levels in the visceral adipose tissue (VAT). Metagenomic analysis of bacterial 16S gene revealed increased Proteobacteria and Bacteroidetes phyla, the main representatives of Gram-negative bacteria, and reduced Akkermansia muciniphila in the fecal samples of IL-17RA-/- mice fed the HFD. Together, these data indicate that the IL-17/IL-17R axis drives intestinal neutrophil migration, limits gut dysbiosis and attenuates LPS translocation to VAT, resulting in protection to MetS.

Prostaglandins D2 and E2 have opposite effects on alveolar macrophages infected with Histoplasma capsulatum.

Prostaglandin E2 (PGE2) suppresses macrophage effector mechanisms; however, little is known about the function of PGD2 in infected alveolar macrophages (AMs). Using serum-opsonized Histoplasma capsulatum (Ops-H. capsulatum) in vitro, we demonstrated that AMs produced PGE2 and PGD2 in a time-dependent manner, with PGE2 levels exceeding those of PGD2 by 48 h postinfection. Comparison of the effects of both exogenous PGs on AMs revealed that PGD2 increased phagocytosis and killing through the chemoattractant receptor-homologous molecule expressed on Th2 lymphocytes receptor, whereas PGE2 had opposite effects, through E prostanoid (EP) receptor 2 (EP2)/EP4-dependent mechanisms. Moreover, PGD2 inhibited phospholipase C-γ (PLC-γ) phosphorylation, reduced IL-10 production, and increased leukotriene B4 receptor expression. In contrast, exogenous PGE2 treatment reduced PLC-γ phosphorylation, p38 and nuclear factor κB activation, TNF-α, H2O2, and leukotriene B4, but increased IL-1ß production. Using specific compounds to inhibit the synthesis of each PG in vitro and in vivo, we found that endogenous PGD2 contributed to fungicidal mechanisms and controlled inflammation, whereas endogenous PGE2 decreased phagocytosis and killing of the fungus and induced inflammation. These findings demonstrate that, although PGD2 acts as an immunostimulatory mediator to control H. capsulatum infection, PGE2 has immunosuppressive effects, and the balance between these two PGs may limit collateral immune damage at the expense of microbial containment.

Interleukin-23 promotes intestinal T helper type17 immunity and ameliorates obesity-associated metabolic syndrome in a murine high-fat diet model.

We addressed the role of interleukin-23 (IL-23) in driving the intestinal T helper type 17 (Th17) response during obesity and metabolic syndrome progression induced by a high-fat diet (HFD). Diet-induced obese and lean mice received HFD or control diet (CTD), respectively, for 20 weeks. The nutritional, metabolic and immune parameters were examined at weeks 9 and 20. Gene and protein IL-23p19 and IL-23 receptor expression was increased in the ileum of obese wild-type mice (WT) fed the HFD for 9 weeks. Mice lacking IL-23 and fed the HFD exhibited greater weight gain, higher fat accumulation, adipocyte hypertrophy and hepatic steatosis. Notably, these mice had more glucose intolerance, insulin resistance and associated metabolic alterations, such as hyperinsulinaemia and hyperlipidaemia. IL-23 deficiency also significantly reduced protein levels of IL-17, CCL20 and neutrophil elastase in the ileum and reduced Th17 cell expansion in the mesenteric lymph nodes of the HFD mice. Of importance, IL-23-deficient mice exhibited increased gut permeability and blood bacterial translocation compared with WT mice fed HFD. Finally, metagenomics analysis of gut microbiota revealed a dramatic outgrowth of Bacteroidetes over Firmicutes phylum with the prevalence of Bacteroides genera in the faeces of IL-23-deficient mice after HFD. In summary, IL-23 appears to maintain the Th17 response and neutrophil migration into the intestinal mucosa, minimizing the gut dysbiosis and protecting against obesity and metabolic disease development in mice.

Oral administration of Saccharomyces cerevisiae UFMG A-905 prevents allergic asthma in mice.

BACKGROUND AND OBJECTIVE: The prevalence of asthma has increased in communities that adopt a Western lifestyle and become more urbanized. Probiotics may be effective in the prevention of allergic diseases, such as asthma. The aim of the current study was to examine the effects of Saccharomyces cerevisiae UFMG A-905 in an allergic model of asthma. METHODS: Balb/c mice were sensitized twice with ovalbumin (OVA) intraperitoneally, 1 week apart and challenged with OVA intranasally for 3 days. Mice were daily treated with S. cerevisiae UFMG A-905 via gavaging needle 10 days before OVA sensitization and during challenges. After challenge, in vivo lung function was measured, and bronchoalveolar lavage (BAL) and lung inflammation were assessed. RESULTS: Oral treatment with S. cerevisiae UFMG A-905 significantly decreased airway hyperresponsiveness, total cell number and the influx of eosinophils to the airway, inflammatory cell in the lung, mucus expression in epithelial cells and the levels of IL-4, IL-5 and IL-13. Additionally, S. cerevisiae UFMG A-905 restored the levels of IL-10 and interferon (IFN)-gamma, and increased the levels of IL-17A. CONCLUSION: Oral administration of S. cerevisiae UFMG A-905 prevented the development of major asthma-like characteristics in a mouse model.

Increased Atrial ß-Adrenergic Receptors and GRK-2 Gene Expression Can Play a Fundamental Role in Heart Failure After Repair of Congenital Heart Disease with Cardiopulmonary Bypass.

Surgeries to correct congenital heart diseases are increasing in Brazil and worldwide. However, even with the advances in surgical techniques and perfusion, some cases, especially the more complex ones, can develop heart failure and death. A retrospective study of patients who underwent surgery for correction of congenital heart diseases with cardiopulmonary bypass (CPB) in a university tertiary-care hospital that died, showed infarction in different stages of evolution and scattered microcalcifications in the myocardium, even without coronary obstruction. CPB is a process routinely used during cardiac surgery for congenital heart disease. However, CPB has been related to increased endogenous catecholamines that can lead to major injuries in cardiomyocytes. The mechanisms involved are not completely understood. The aim of this study was to evaluate the alterations induced in the ß-adrenergic receptors and GRK-2 present in atrial cardiomyocytes of infants with congenital heart disease undergoing surgical repair with CPB and correlate the alterations with functional and biochemical markers of ischemia/myocardial injury. The study consisted of right atrial biopsies of infants undergoing surgical correction in HC-FMRPUSP. Thirty-three cases were selected. Atrial biopsies were obtained at the beginning of CPB (group G1) and at the end of CPB (group G2). Real-time PCR, Western blotting, and immunofluorescence analysis were conducted to evaluate the expression of ß1, ß2-adrenergic receptors, and GRK-2 in atrial myocardium. Cardiac function was evaluated by echocardiography and biochemical analysis (N-terminal pro-brain natriuretic peptide (NT-ProBNP), lactate, and cardiac troponin I). We observed an increase in serum lactate, NT-proBNP, and troponin I at the end of CPB indicating tissue hypoxia/ischemia. Even without major clinical consequences in cardiac function, these alterations were followed by a significant increase in gene expression of ß1 and ß2 receptors and GRK-2, suggesting that this is one of the mechanisms responsible for the exacerbated response of cardiomyocytes to circulating catecholamines. These alterations could explain the irreversible myocardial damage and lipid peroxidation of membranes classically attributed to catecholamine excess, observed in some infants who develop heart failure and postoperative death. Although other factors may be involved, this study confirms that CPB acts as a potent inducer of increased gene expression of ß- adrenergic receptors and GRK-2, making the myocardium of these infants more susceptible to the effects of circulating endogenous catecholamines, which may contribute to the development of irreversible myocardial damage and death.

Mast cells control insulitis and increase Treg cells to confer protection against STZ-induced type 1 diabetes in mice.

Quantitative alterations in mast cell numbers in pancreatic lymph nodes (PLNs) have been reported to be associated with type 1 diabetes (T1D) progression, but their potential role during T1D remains unclear. In this study, we evaluated the role of mast cells in T1D induced by multiple low-dose streptozotocin (MLD-STZ) treatments, using two strains of mast cell-deficient mice (W/W(v) or Wsh/Wsh) and the adoptive transfer of mast cells. Mast cell deficient mice developed severe insulitis and accelerated hyperglycemia, with 100% of mice becoming diabetic compared to their littermates. In parallel, these diabetic mice had decreased numbers of T regulatory (Treg) cells in the PLNs. Additionally, mast cell deficiency caused a significant reduction in IL-10, TGF-ß, and IL-6 expression in the pancreatic tissue. Interestingly, IL-6-deficient mice are more susceptible to T1D associated with reduced Treg-cell numbers in the PLNs, but mast cell transfer from wild-type mice induced protection to T1D in these mice. Finally, mast cell adoptive transfer prior to MLD-STZ administration conferred resistance to T1D, promoted increased Treg cells, and decreased IL-17-producing T cells in the PLNs. Taken together, our results indicate that mast cells are implicated in resistance to STZ-induced T1D via an immunological tolerance mechanism mediated by Treg cells.

Reduced expression of adherens and gap junction proteins can have a fundamental role in the development of heart failure following cardiac hypertrophy in rats.

Hypertension causes cardiac hypertrophy, cardiac dysfunction and heart failure (HF). The mechanisms implicated in the transition from compensated to decompensated cardiac hypertrophy are not fully understood. This study was aimed to investigate whether alterations in the expression of intercalated disk proteins could contribute to the transition of compensated cardiac hypertrophy to dilated heart development that culminates in HF. Male rats were submitted to abdominal aortic constriction and at 90 days post surgery (dps), three groups were observed: sham-operated animals (controls), animals with hypertrophic hearts (HH) and animals with hypertrophic + dilated hearts (HD). Blood pressure was evaluated. The hearts were collected and Western blot and immunofluorescence were performed to desmoglein-2, desmocollin-2, N-cadherin, plakoglobin, Bcatenin, and connexin-43. Cardiac systolic function was evaluated using the Vevo 2100 ultrasound system. Data were considered significant when p b 0.05. Seventy percent of the animals presented with HH and 30% were HD at 90 dps. The blood pressure increased in both groups. The amount of desmoglein-2 and desmocollin-2 expression was increased in both groups and no difference was observed in either group. The expression of N-cadherin, plakoglobin and B-catenin increased in the HHgroup and decreased in the HDgroup; and connexin-43 decreased only in theHDgroup. Therewas no difference between the ejection fraction and fractional shortening at 30 and 60 dps; however, they were decreased in the HD group at 90 dps. We found that while some proteins have increased expression accompanied by the increase in the cell volume associated with preserved systolic cardiac function in theHHgroup, these same proteins had decreased expression evenwithout significant reduction in the cell volume associated with decreased systolic cardiac function in HD group. The increased expression of desmoglein-2 and desmocollin-2 in both the HH and HD groups could work as a protective compensatory mechanism, helping tomaintain the dilated heart.We can hypothesize that inappropriate intercellular mechanical and electrical coupling associated with necrosis and/or apoptosis are important factors contributing to the transition to HF.

Synergy of chemotherapy and immunotherapy revealed by a genome-scale analysis of murine tuberculosis.

OBJECTIVES: Although TB immunotherapy improves the results of conventional drug treatment, the effects of combining chemotherapy and immunotherapy have never been systematically evaluated. We used a comprehensive lung transcriptome analysis to directly compare the activity of combined chemotherapy and immunotherapy with that of single treatments in a mouse model of TB. METHODS: Mycobacterium tuberculosis-infected mice in the chronic phase of the disease (day 30) received: (i) isoniazid and rifampicin (drugs) daily for 30 days; (ii) DNA immunotherapy (DNA), consisting of four 100 µg injections at 10 day intervals; (iii) both therapies (DNA + drugs); or (iv) saline. The effects were evaluated 10 days after the end of treatment (day 70 post-infection). RESULTS: In all groups a systemic reduction in the load of bacilli was observed, bacilli became undetectable in the drugs and DNA + drugs groups, but the whole lung transcriptome analysis showed 867 genes exclusively modulated by the DNA + drugs combination. Gene enrichment analysis indicated that DNA + drugs treatment provided synergistic effects, including the down-regulation of proinflammatory cytokines and mediators of fibrosis, as confirmed by real-time PCR, ELISA, histopathology and hydroxyproline assay. CONCLUSIONS: Our results provide a molecular basis for the advantages of TB treatment using combined chemotherapy and DNA immunotherapy and demonstrate the synergistic effects obtained with this strategy.

Autopsy for Medical Diagnostics: Finding the Cause of Sudden Unexpected Death through Investigation of the Cardiac Conduction System by Serial Sections.

Sudden unexpected death (SUD) is a fatal event that occurs in an apparently healthy subject in a way that such an abrupt outcome could have not been predicted. SUD-including sudden intrauterine unexplained death (SIUD), sudden neonatal unexpected death (SNUD), sudden infant death syndrome (SIDS), sudden unexpected death of the young (SUDY), and sudden unexpected death in the adult (SUDA)-occurs as the first manifestation of an unknown underlying disease or within a few hours of the presentation of a disease. SUD is a major unsolved, shocking form of death that occurs frequently and can happen at any time without warning. For each case of SUD, a review of clinical history data and performance of a complete autopsy, particularly focused on the study of the cardiac conduction system, were carried out according to the necropsy protocol devised by the Lino Rossi Research Center, Università degli Studi di Milano, Italy. Research cases collected and selected for this study were represented by 75 SUD victims that were subdivided into 15 SIUD, 15 SNUD, 15 SUDY, and 15 SUDA victims. After a routine autopsy and clinical history analysis, death remained unexplained, and hence a diagnosis of SUD was assigned to 75 subjects, which included 45 females (60%) and 30 (40%) males ranging in age from 27 gestational weeks to 76 years. Serial sections of the cardiac conduction system disclosed frequent congenital alterations of the cardiac conduction system in fetuses and infants. An age-related significant difference in distribution among the five age-related groups was detected for the following anomalies of the conduction system: central fibrous body (CFB) islands of conduction tissue, fetal dispersion, resorptive degeneration, Mahaim fiber, CFB cartilaginous meta-hyperplasia, His bundle septation, sino-atrial node (SAN) artery fibromuscular thickening, atrio-ventricular junction hypoplasia, intramural right bundle branch, and SAN hypoplasia. The results are useful for understanding the cause of death for all SUD cases that were unexpected and would have otherwise remained unexplained, so as to motivate medical examiners and pathologists to perform more in-depth studies.

Modulation of the mTOR Pathway by Curcumin in the Heart of Septic Mice.

mTOR is a signaling pathway involved in cell survival, cell stress response, and protein synthesis that may be a key point in sepsis-induced cardiac dysfunction. Curcumin has been reported in vitro as an mTOR inhibitor compound; however, there are no studies demonstrating this effect in experimental sepsis. Thus, this study aimed to evaluate the action of curcumin on the mTOR pathway in the heart of septic mice. Free curcumin (FC) and nanocurcumin (NC) were used, and samples were obtained at 24 and 120 h after sepsis. Histopathological and ultrastructural analysis showed that treatments with FC and NC reduced cardiac lesions caused by sepsis. Our main results demonstrated that curcumin reduced mTORC1 and Raptor mRNA at 24 and 120 h compared with the septic group; in contrast, mTORC2 mRNA increased at 24 h. Additionally, the total mTOR mRNA expression was reduced at 24 h compared with the septic group. Our results indicate that treatment with curcumin and nanocurcumin promoted a cardioprotective response that could be related to the modulation of the mTOR pathway.

Promotion of neutralizing antibody-independent immunity to wild-type and SARS-CoV-2 variants of concern using an RBD-Nucleocapsid fusion protein.

Both T cells and B cells have been shown to be generated after infection with SARS-CoV-2 yet protocols or experimental models to study one or the other are less common. Here, we generate a chimeric protein (SpiN) that comprises the receptor binding domain (RBD) from Spike (S) and the nucleocapsid (N) antigens from SARS-CoV-2. Memory CD4+ and CD8+ T cells specific for SpiN could be detected in the blood of both individuals vaccinated with Coronavac SARS-CoV-2 vaccine and COVID-19 convalescent donors. In mice, SpiN elicited a strong IFN-γ response by T cells and high levels of antibodies to the inactivated virus, but not detectable neutralizing antibodies (nAbs). Importantly, immunization of Syrian hamsters and the human Angiotensin Convertase Enzyme-2-transgenic (K18-ACE-2) mice with Poly ICLC-adjuvanted SpiN promotes robust resistance to the wild type SARS-CoV-2, as indicated by viral load, lung inflammation, clinical outcome and reduction of lethality. The protection induced by SpiN was ablated by depletion of CD4+ and CD8+ T cells and not transferred by antibodies from vaccinated mice. Finally, vaccination with SpiN also protects the K18-ACE-2 mice against infection with Delta and Omicron SARS-CoV-2 isolates. Hence, vaccine formulations that elicit effector T cells specific for the N and RBD proteins may be used to improve COVID-19 vaccines and potentially circumvent the immune escape by variants of concern.

IFN-γ-mediated efficacy of allergen-free immunotherapy using mycobacterial antigens and CpG-ODN.

Epidemiological and experimental evidence supports the notion that microbial infections that are known to induce Th1-type immune responses can suppress Th2 immune responses, which are characteristics of allergic disorders. However, live microbial immunization might not be feasible for human immunotherapy. Here, we evaluated whether induction of Th1 immunity by the immunostimulatory sequences of CpG-oligodeoxynucleotides (CpG-ODN), with or without culture filtrate proteins (CFP), from Mycobacterium tuberculosis would suppress ongoing allergic lung disease. Presensitized and ovalbumin (OVA)-challenged mice were treated subcutaneously with CpG, or CpG in combination with CFP (CpG/CFP). After 15 days of treatment, airway inflammation and specific T- and B-cell responses were determined. Cell transfer experiments were also performed. CpG treatment attenuated airway allergic disease; however, the combination CpG/CFP treatment was significantly more effective in decreasing airway hyperresponsiveness, eosinophilia and Th2 response. When an additional intranasal dose of CFP was given, allergy was even more attenuated. The CpG/CFP therapy also reduced allergen-specific IgG1 and IgE antibodies and increased IgG2a. Transfer of spleen cells from mice immunized with CpG/CFP also reduced allergic lung inflammation. CpG/CFP treatment induced CFP-specific production of IFN-γ and IL-10 by spleen cells and increased production of IFN-γ in response to OVA. The essential role of IFN-γ for the therapeutic effect of CpG/CFP was evidenced in IFN-γ knockout mice. These results show that CpG/CFP treatment reverses established Th2 allergic responses by an IFN-γ-dependent mechanism that seems to act both locally in the lung and systemically to decrease allergen-specific Th2 responses.

Combining two potential causes of metalloproteinase secretion causes abdominal aortic aneurysms in rats: a new experimental model.

Progress in understanding the pathophysiology of abdominal aortic aneurysms (AAA) is dependent in part on the development and application of effective animal models that recapitulate key aspects of the disease. The objective was to produce an experimental model of AAA in rats by combining two potential causes of metalloproteinase (MMP) secretion: inflammation and turbulent blood flow. Male Wistar rats were randomly divided in four groups: Injury, Stenosis, Aneurysm and Control (40/group). The Injury group received a traumatic injury to the external aortic wall. The Stenosis group received an extrinsic stenosis at a corresponding location. The Aneurysm group received both the injury and stenosis simultaneously, and the Control group received a sham operation. Animals were euthanized at days 1, 3, 7 and 15. Aorta and/or aneurysms were collected and the fragments were fixed for morphologic, immunohistochemistry and morphometric analyses or frozen for MMP assays. AAAs had developed by day 3 in 60-70% of the animals, reaching an aortic dilatation ratio of more than 300%, exhibiting intense wall remodelling initiated at the adventitia and characterized by an obvious inflammatory infiltrate, mesenchymal proliferation, neoangiogenesis, elastin degradation and collagen deposition. Immunohistochemistry and zymography studies displayed significantly increased expressions of MMP-2 and MMP-9 in aneurysm walls compared to other groups. The haemo-dynamic alterations caused by the stenosis may have provided additional contribution to the MMPs liberation. This new model illustrated that AAA can be multifactorial and confirmed the key roles of MMP-2 and MMP-9 in this dynamic remodelling process.

Assessment of MMP-9, TIMP-1, and COX-2 in normal tissue and in advanced symptomatic and asymptomatic carotid plaques.

BACKGROUND: Mature carotid plaques are complex structures, and their histological classification is challenging. The carotid plaques of asymptomatic and symptomatic patients could exhibit identical histological components. OBJECTIVES: To investigate whether matrix metalloproteinase 9 (MMP-9), tissue inhibitor of MMP (TIMP), and cyclooxygenase-2 (COX-2) have different expression levels in advanced symptomatic carotid plaques, asymptomatic carotid plaques, and normal tissue. METHODS: Thirty patients admitted for carotid endarterectomy were selected. Each patient was assigned preoperatively to one of two groups: group I consisted of symptomatic patients (n = 16, 12 males, mean age 66.7 ± 6.8 years), and group II consisted of asymptomatic patients (n = 14, 8 males, mean age 67.6 ± 6.81 years). Nine normal carotid arteries were used as control. Tissue specimens were analyzed for fibromuscular, lipid and calcium contents. The expressions of MMP-9, TIMP-1 and COX-2 in each plaque were quantified. RESULTS: Fifty-eight percent of all carotid plaques were classified as Type VI according to the American Heart Association Committee on Vascular Lesions. The control carotid arteries all were classified as Type III. The median percentage of fibromuscular tissue was significantly greater in group II compared to group I (p < 0.05). The median percentage of lipid tissue had a tendency to be greater in group I than in group II (p = 0.057). The percentages of calcification were similar among the two groups. MMP-9 protein expression levels were significantly higher in group II and in the control group when compared with group I (p < 0.001). TIMP-1 expression levels were significantly higher in the control group and in group II when compared to group I, with statistical difference between control group and group I (p = 0.010). COX-2 expression levels did not differ among groups. There was no statistical correlation between MMP-9, COX-2, and TIMP-1 levels and fibrous tissue. CONCLUSIONS: MMP-9 and TIMP-1 are present in all stages of atherosclerotic plaque progression, from normal tissue to advanced lesions. When sections of a plaque are analyzed without preselection, MMP-9 concentration is higher in normal tissues and asymptomatic surgical specimens than in symptomatic specimens, and TIMP-1 concentration is higher in normal tissue than in symptomatic specimens.

Videodensitometric analysis of advanced carotid plaque: correlation with MMP-9 and TIMP-1 expression.

BACKGROUND: Matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of MMP (TIMP) promote derangement of the extracellular matrix, which is ultimately reflected in plaque images seen on ultrasound. Videodensitometry can identify structural disturbances in plaques. OBJECTIVES: To establish the correlations between values determined using videodensitometry in B-mode ultrasound images of advanced carotid plaques and the total expression of MMP-9 and TIMP-1 in these removed plaques. METHODS: Thirty patients underwent ultrasonic tissue characterization of carotid plaques before surgery, using mean gray level (MGL), energy, entropy and homogeneity. Each patient was assigned preoperatively to one of 2 groups: group I, symptomatic patients (n = 16; 12 males; mean age 66.7 ± 6.8 years), and group II, asymptomatic patients (n = 14; 8 males; mean age 67.6 ± 6.81 years). Tissue specimens were analyzed for MMP-9 and TIMP-1 expression. Nine carotid arteries were used as normal tissue controls. RESULTS: MMP-9 expression levels were elevated in group II and in normal tissues compared to group I (p < 0.001). TIMP-1 levels were higher in group II than in group I, and significantly higher in normal tissues than in group I (p = 0.039). The MGL was higher in group II compared to group I (p = 0.038). Energy had greater values in group II compared to group I (p = 0.02). There were no differences between patient groups in homogeneity and entropy. Energy positively correlated with MMP-9 and TIMP-1 expression (p = 0.012 and p = 0.031 respectively). Homogeneity positively correlated with MMP-9 and TIMP-1 expression (p = 0.034 and p = 0.047 respectively). There were no correlations between protein expression and MGL or entropy. CONCLUSIONS: Videodensitometric computer analysis of ultrasound scanning images can be used to identify stable carotid plaques, which have higher total expression levels of MMP-9 and TIMP-1 than unstable plaques.

Sudden Unexpected Death Associated with Arrhythmogenic Cardiomyopathy: Study of the Cardiac Conduction System.

A retrospective study was conducted on pathologically diagnosed arrhythmogenic cardiomyopathy (ACM) from consecutive cases over the past 34 years (n = 1109). The anatomo-pathological analyses were performed on 23 hearts diagnosed as ACM (2.07%) from a series of 1109 suspected cases, while histopathological data of cardiac conduction system (CCS) were available for 15 out of 23 cases. The CCS was removed in two blocks, containing the following structures: Sino-atrial node (SAN), atrio-ventricular junction (AVJ) including the atrio-ventricular node (AVN), the His bundle (HB), the bifurcation (BIF), the left bundle branch (LBB) and the right bundle branch (RBB). The ACM cases consisted of 20 (86.96%) sudden unexpected cardiac death (SUCD) and 3 (13.04%) native explanted hearts; 16 (69.56%) were males and 7 (30.44%) were females, ranging in age from 5 to 65 (mean age ± SD, 36.13 ± 16.06) years. The following anomalies of the CCS, displayed as percentages of the 15 ACM SUCD cases in which the CCS has been fully analyzed, have been detected: Hypoplasia of SAN (80%) and/or AVJ (86.67%) due to fatty-fibrous involvement, AVJ dispersion and/or septation (46.67%), central fibrous body (CFB) hypoplasia (33.33%), fibromuscular dysplasia of SAN (20%) and/or AVN (26.67%) arteries, hemorrhage and infarct-like lesions of CCS (13.33%), islands of conduction tissue in CFB (13.33%), Mahaim fibers (13.33%), LBB block by fibrosis (13.33%), AVN tongue (13.33%), HB duplicity (6.67%%), CFB cartilaginous meta-hyperplasia (6.67%), and right sided HB (6.67%). Arrhythmias are the hallmark of ACM, not only from the fatty-fibrous disruption of the ventricular myocardium that accounts for reentrant ventricular tachycardia, but also from the fatty-fibrous involvement of CCS itself. Future research should focus on application of these knowledge on CCS anomalies to be added to diagnostic criteria or at least to be useful to detect the patients with higher sudden death risks.

Curcumin as a Potential Treatment for COVID-19.

Coronavirus disease 2019 (COVID-19) is an infectious disease that rapidly spread throughout the world leading to high mortality rates. Despite the knowledge of previous diseases caused by viruses of the same family, such as MERS and SARS-CoV, management and treatment of patients with COVID-19 is a challenge. One of the best strategies around the world to help combat the COVID-19 has been directed to drug repositioning; however, these drugs are not specific to this new virus. Additionally, the pathophysiology of COVID-19 is highly heterogeneous, and the way of SARS-CoV-2 modulates the different systems in the host remains unidentified, despite recent discoveries. This complex and multifactorial response requires a comprehensive therapeutic approach, enabling the integration and refinement of therapeutic responses of a given single compound that has several action potentials. In this context, natural compounds, such as Curcumin, have shown beneficial effects on the progression of inflammatory diseases due to its numerous action mechanisms: antiviral, anti-inflammatory, anticoagulant, antiplatelet, and cytoprotective. These and many other effects of curcumin make it a promising target in the adjuvant treatment of COVID-19. Hence, the purpose of this review is to specifically point out how curcumin could interfere at different times/points during the infection caused by SARS-CoV-2, providing a substantial contribution of curcumin as a new adjuvant therapy for the treatment of COVID-19.

Effect of Verapamil, an L-Type Calcium Channel Inhibitor, on Caveolin-3 Expression in Septic Mouse Hearts.

Sepsis-induced myocardial dysfunction considerably increases mortality risk in patients with sepsis. Previous studies from our group have shown that sepsis alters the expression of structural proteins in cardiac cells, resulting in cardiomyocyte degeneration and impaired communication between cardiac cells. Caveolin-3 (CAV3) is a structural protein present in caveolae, located in the membrane of cardiac muscle cells, which regulates physiological processes such as calcium homeostasis. In sepsis, there is a disruption of calcium homeostasis, which increases the concentration of intracellular calcium, which can lead to the activation of potent cellular enzymes/proteases which cause severe cellular injury and death. The purpose of the present study was to test the hypotheses that sepsis induces CAV3 overexpression in the heart, and the regulation of L-type calcium channels directly relates to the regulation of CAV3 expression. Severe sepsis increases the expression of CAV3 in the heart, as immunostaining in our study showed CAV3 presence in the cardiomyocyte membrane and cytoplasm, in comparison with our control groups (without sepsis) that showed CAV3 presence predominantly in the plasma membrane. The administration of verapamil, an L-type calcium channel inhibitor, resulted in a decrease in mortality rates of septic mice. This effect was accompanied by a reduction in the expression of CAV3 and attenuation of cardiac lesions in septic mice treated with verapamil. Our results indicate that CAV3 has a vital role in cardiac dysfunction development in sepsis and that the regulation of L-type calcium channels may be related to its expression.

Disruption of sarcolemmal dystrophin and beta-dystroglycan may be a potential mechanism for myocardial dysfunction in severe sepsis.

Evidence from our laboratory has shown alterations in myocardial structure in severe sepsis/septic shock. The morphological alterations are heralded by sarcolemmal damage, characterized by increased plasma membrane permeability caused by oxidative damage to lipids and proteins. The critical importance of the dystrophin-glycoprotein complex (DGC) in maintaining sarcolemmal stability led us to hypothesize that loss of dystrophin and associated glycoproteins could be involved in early increased sarcolemmal permeability in experimentally induced septic cardiomyopathy. Male C57Bl/6 mice were subjected to sham operation and moderate (MSI) or severe (SSI) septic injury induced by cecal ligation and puncture (CLP). Using western blot and immunofluorescence, a downregulation of dystrophin and beta-dystroglycan expression in both severe and moderate injury could be observed in septic hearts. The immunofluorescent and protein amount expressions of laminin-alpha2 were similar in SSI and sham-operated hearts. Consonantly, the evaluation of plasma membrane permeability by intracellular albumin staining provided evidence of severe injury of the sarcolemma in SSI hearts, whereas antioxidant treatment significantly attenuated the loss of sarcolemmal dystrophin expression and the increased membrane permeability. This study offers novel and mechanistic data to clarify subcellular events in the pathogenesis of cardiac dysfunction in severe sepsis. The main finding was that severe sepsis leads to a marked reduction in membrane localization of dystrophin and beta-dystroglycan in septic cardiomyocytes, a process that may constitute a structural basis of sepsis-induced cardiac depression. In addition, increased sarcolemmal permeability suggests functional impairment of the DGC complex in cardiac myofibers. In vivo observation that antioxidant treatment significantly abrogated the loss of dystrophin expression and plasma membrane increased permeability supports the hypothesis that oxidative damage may mediate the loss of dystrophin and beta-dystroglycan in septic mice. These abnormal parameters emerge as therapeutic targets and their modulation may provide beneficial effects on future cardiovascular outcomes and mortality in sepsis.

Interleukin-1 Receptor-Induced Nitric Oxide Production in the Pancreas Controls Hyperglycemia Caused by Scorpion Envenomation.

Tityus serrulatus causes numerous scorpion envenomation accidents and deaths worldwide. The symptoms vary from local to systemic manifestations, culminating in pulmonary edema and cardiogenic shock. Among these events, transitory hyperglycemia is a severe manifestation that influences pulmonary edema, hemodynamic alterations, and cardiac disturbances. However, the molecular mechanism that leads to increased glucose levels after T. serrulatus envenomation remains unknown. This study aimed to investigate our hypothesis that hyperglycemia due to scorpion envenomation involves inflammatory signaling in the pancreas. The present study showed that T. serrulatus venom induces the production of IL-1α and IL-1ß in the pancreas, which signal via IL-1R and provoke nitric oxide (NO) production as well as edema in ß-cells in islets. Il1r1-/- mice were protected from transitory hyperglycemia and did not present disturbances in insulin levels in the serum. These results suggest that the pathway driven by IL-1α/IL-1ß-IL-1R-NO inhibits insulin release by ß-cells, which increases systemic glucose concentration during severe scorpion envenomation. A supportive therapy that inhibits NO production, combined with antiserum, may help to prevent fatal outcomes of scorpion envenomation. Our findings provide novel insights into the design of supportive therapy with NO inhibitors combined with antiscorpion venom serum to overcome fatal outcomes of scorpion envenomation.