Epigenetic drug ameliorated type 1 diabetes via decreased generation of Th1 and Th17 subsets and restoration of self-tolerance in CD4+ T cells.

Female NOD mice develop autoimmune diabetes spontaneously without extrinsic manipulation. Previously, we have shown that weekly administration of the prediabetic female NOD mice with the histone modifier Trichostatin A (TSA) prevented diabetes onset. Herein we show that T lymphocytes from diabetic mice transferred diabetes into immunodeficient NOD.scid recipients while those isolated from drug-treated mice displayed reduced disease-causing ability. Drug treatment also repressed T cell receptor-mediated IFN-γ transcription. Splenic CD4+ T-cells purified from prediabetic mice could be polarized into IFN-γ -producing Th1 and IL-17A-expressing Th17 subsets ex vivo. Adoptive transfer of these cells into immunocompromised NOD.scid mice caused diabetes comparably. Polarized Th1 cells were devoid of IL-17A-producing cells and did not transdifferentiate into Th17 cells in the spleen of immunodeficient recipients. However, polarized Th17 cell preparation had a few contaminant Th1 cells. Adoptive transfer of polarized Th17 cells into NOD.scid recipients led to IFN-γ transcription in recipient splenocytes. Notably, TSA treatment of prediabetic mice abolished the ability of CD4+ T-cells to differentiate into diabetogenic Th1 and Th17 cells ex vivo. This was accompanied by the absence of Ifng and Il17a transcription in the spleen of NOD.scid recipients receiving cells, respectively cultured under Th1 and Th17 polarizing conditions. Significantly, the histone modifier restored the ability of CD4+ but not CD8+ T-cells to undergo CD3-mediated apoptosis ex vivo in a caspase-dependent manner. These results indicate that the histone modifier bestowed protection against type 1 diabetes via negative regulation of signature lymphokines and restitution of self-tolerance in CD4+ T cells.

Human glycocalyx shedding: Systematic review and critical appraisal.

BACKGROUND: The number of studies measuring breakdown products of the glycocalyx in plasma has increased rapidly during the past decade. The purpose of the present systematic review was to assess the current knowledge concerning the association between plasma concentrations of glycocalyx components and structural assessment of the endothelium. METHODS: We performed a literature review of Pubmed to determine which glycocalyx components change in a wide variety of human diseases and conditions. We also searched for evidence of a relationship between plasma concentrations and the thickness of the endothelial glycocalyx layer as obtained by imaging methods. RESULTS: Out of 3,454 publications, we identified 228 that met our inclusion criteria. The vast majority demonstrate an increase in plasma glycocalyx products. Sepsis and trauma are most frequently studied, and comprise approximately 40 publications. They usually report 3-4-foldt increased levels of glycocalyx degradation products, most commonly of syndecan-1. Surgery shows a variable picture. Cardiac surgery and transplantations are most likely to involve elevations of glycocalyx degradation products. Structural assessment using imaging methods show thinning of the endothelial glycocalyx layer in cardiovascular conditions and during major surgery, but thinning does not always correlate with the plasma concentrations of glycocalyx products. The few structural assessments performed do not currently support that capillary permeability is increased when the plasma levels of glycocalyx fragments in plasma are increased. CONCLUSIONS: Shedding of glycocalyx components is a ubiquitous process that occurs during both acute and chronic inflammation with no sensitivity or specificity for a specific disease or condition.

Atypical Takotsubo Cardiomyopathy with Hypokinetic Left Mid-ventricle and Apical Wall Sparing: A Case Report and Literature Review.

BACKGROUND: Takotsubo Cardiomyopathy (TTC) is an uncommon cause of acute reversible ventricular systolic dysfunction in the absence of obstructive Coronary Artery Disease (CAD). Typically manifesting as apical wall ballooning, TTC can rarely present atypically with apical wall sparing. CASE REPORT: A 62-year-old female presented with complaints of chest pain and features mimicking acute coronary syndrome. Coronary angiogram revealed no obstructive CAD and left ventriculogram showed reduced ejection fraction, normal left ventricular apex and hypokinetic mid-ventricles consistent with atypical TTC. The patient was discharged home on heart failure medications and a follow-up transthoracic echocardiogram demonstrated improved left ventricular function with no wall motion abnormality. CONCLUSION: This case report provides an insight into the diagnosis and management of TTC in the absence of pathognomic features.

Implications of Left Bundle Branch Block in Takotsubo Cardiomyopathy: Propensity Match Analysis from the National Inpatient Sample.

INTRODUCTION: Takotsubo cardiomyopathy (TTC), also called stress cardiomyopathy, is a transient reversible left ventricular dysfunction mimicking acute coronary syndrome (ACS). Studies have shown similar rates of in-hospital complications in TTC and myocardial infarction (MI). Left bundle branch block (LBBB) is associated with increased mortality in patients with MI; however, similar studies comparing outcomes of TTC in the presence of LBBB are lacking. METHODS: The 2016 National Inpatient Sample (NIS) database was queried to identify all admissions with a primary discharge diagnosis of TTC. Diagnosis-specific codes were used to stratify patients based on the presence or absence of LBBB. Both population sets were paired using 1:10 propensity score matching. Multivariate logistic regression analysis was performed to compare various in-hospital outcomes among both groups. RESULTS: Amongst 7270 admissions for TTC, 226 patients had concomitant LBBB. After performing 1:10 propensity matching, 130 patients with LBBB were compared to 1275 patients without LBBB. The presence of LBBB was associated with increased odds of cardiogenic shock (AOR = 2.2, 95% CI 1.21-3.99, p = 0.0097); ventricular arrhythmia (AOR 1.99, 95% CI 1.11-3.57, p = 0.02), acute congestive heart failure (AOR = 1.49, 95% CI 1.01-2.2, p = 0.04), and sudden cardiac arrest (AOR = 3.37, 95% CI 1.59-7.13, p = 0.0001). There was no statistical difference in all-cause in-hospital mortality, however a trend towards worsening was noted. CONCLUSIONS: The incidence of arrhythmia and shock in patients with TTC does not correlate with the extent of myocardium involvement. The presence of LBBB in such cases can help recognize at-risk populations, and with timely intervention, life-threatening complications can be avoided. Despite limitations of the dataset and inability to establish causality, prospective studies with longer follow-up are warranted.

Transcriptome analysis of epigenetically modulated genome indicates signature genes in manifestation of type 1 diabetes and its prevention in NOD mice.

Classic genetic studies implicated several genes including immune response genes in the risk of developing type 1 diabetes in humans. However, recent evidence including discordant diabetes incidence among monozygotic twins suggested a role for epigenetics in disease manifestation. NOD mice spontaneously develop type 1 diabetes like humans and serve as an excellent model system to study the mechanisms of type 1 diabetes as well as the efficacy of maneuvers to manipulate the disease. Using this preclinical model, we have recently demonstrated that pharmacological inhibition of histone deacetylases can lead to histone hyperacetylation, selective up-regulation of interferon-γ and its transactivator Tbx21/Tbet, and amelioration of autoimmune diabetes. In the current study, we show that chromatin remodeling can render splenocytes incapable of transferring diabetes into immunodeficient NOD.scid mice. To elucidate the underlying mechanisms of drug-mediated protection against type 1 diabetes, we performed global gene expression profiling of splenocytes using high throughput microarray technology. This unbiased transcriptome analysis unraveled the exaggerated expression of a novel set of closely related inflammatory genes in splenocytes of acutely diabetic mice and their repression in mice cured of diabetes by chromatin remodeling. Analysis of gene expression by qRT-PCR using RNA derived from spleens and pancreata of cured mice validated the suppression of most of these genes, indicating an inverse correlation between the high levels of these inflammatory genes and protection against diabetes in NOD mice. In addition, higher-level expression of genes involved in insulin sensitivity, erythropoiesis, hemangioblast generation, and cellular redox control was evident in spleens of cured mice, indicating their possible contribution to protection against type 1 diabetes. Taken together, these results are consistent with the involvement of epistatic mechanisms in the manifestation of autoimmune diabetes and further indicate the utility of chromatin remodeling in curing this complex autoimmune disorder.

Chromatin remodeling resets the immune system to protect against autoimmune diabetes in mice.

Epigenetic alteration of the genome has been shown to provide palliative effects in mouse models of certain human autoimmune diseases. We have investigated whether chromatin remodeling could provide protection against autoimmune diabetes in NOD mice. Treatment of female mice during the transition from prediabetic to diabetic stage (18-24 weeks of age) with the well-characterized histone deacetylase inhibitor, trichostatin A effectively reduced the incidence of diabetes. However, similar treatment of overtly diabetic mice during the same time period failed to reverse the disease. Protection against diabetes was accompanied by histone hyperacetylation in pancreas and spleen, enhanced frequency of CD4(+) CD62L(+) cells in the spleen, reduction in cellular infiltration of islets, restoration of normoglycemia and glucose-induced insulin release by beta cells. Activation of splenic T lymphocytes derived from protected mice in vitro with pharmacological agents that bypass the antigen receptor or immobilized anti-CD3 antibody resulted in enhanced expression of Ifng mRNA and protein without altering the expression of Il4, Il17, Il18, Inos and Tnfa genes nor the secretion of IL-2, IL-4, IL-17 and TNF-α proteins. Consistently, expression of the transcription factor involved in Ifng transcription, Tbet/Tbx21 but not Gata3 and Rorgt, respectively, required for the transcription of Il4 and Il17, was upregulated in activated splenocytes of protected mice. These results indicate that chromatin remodeling can lead to amelioration of diabetes by using multiple mechanisms including differential gene transcription. Thus, epigenetic modulation could be a novel therapeutic approach to block the transition from benign to frank diabetes.

Transfusion of nonobese diabetic mice with allogeneic newborn blood ameliorates autoimmune diabetes and modifies the expression of selected immune response genes.

Although allogeneic bone marrow transplantation has been shown to prevent autoimmune diabetes in heavily irradiated nonobese diabetic (NOD) mice, a similar procedure is not suitable for the treatment of patients with type 1 diabetes because of associated severe side effects. Therefore, we evaluated whether mouse newborn blood (NBB), equivalent to human umbilical cord blood, could be used for diabetes prevention without recipient preconditioning. To test this hypothesis, unconditioned, prediabetic female NOD mice were given a single injection of whole NBB derived from the allogeneic diabetes-resistant mouse strain C57BL/6. Transfusion of allogeneic NBB but not adult blood prevented diabetes incidence in a majority of treated mice for a prolonged period of time. This was accompanied by the release of insulin in response to a challenge with glucose. Invasive cellular infiltration of islets was also substantially reduced in these mice. Although NBB transfusion induced a low level of hematopoietic microchimerism, it did not strictly correlate with amelioration of diabetes. Induction of genes implicated in diabetes, such as Il18, Tnfa, and Inos but not Il4, Il17 or Ifng, was repressed in splenocytes derived from protected mice. Notably, expression of the transcription factor Tbet/Tbx21 but not Gata3 or Rorgt was upregulated in protected mice. These data indicate that allogeneic NBB transfusion can prevent diabetes in NOD mice associated with modulation of selected cytokine genes implicated in diabetes manifestation. The data presented in this study provide the proof of principle for the utility of allogeneic umbilical cord blood transfusion to treat patients with autoimmune diabetes.