An IQSEC2 Mutation Associated With Intellectual Disability and Autism Results in Decreased Surface AMPA Receptors

We have recently described an A350V mutation in IQSEC2 associated with intellectual disability, autism and epilepsy. We sought to understand the molecular pathophysiology of this mutation with the goal of developing targets for drug intervention. We demonstrate here that the A350V mutation results in interference with the binding of apocalmodulin to the IQ domain of IQSEC2. We further demonstrate that this mutation results in constitutive activation of the guanine nucleotide exchange factor (GEF) activity of IQSEC2 resulting in increased production of the active form of Arf6. In a CRISPR generated mouse model of the A350V IQSEC2 mutation, we demonstrate that the surface expression of GluA2 AMPA receptors in mouse hippocampal tissue was significantly reduced in A350V IQSEC2 mutant mice compared to wild type IQSEC2 mice and that there is a significant reduction in basal synaptic transmission in the hippocampus of A350V IQSEC2 mice compared to wild type IQSEC2 mice. Finally, the A350V IQSEC2 mice demonstrated increased activity, abnormal social behavior and learning as compared to wild type IQSEC2 mice. These findings suggest a model of how the A350V mutation in IQSEC2 may mediate disease with implications for targets for drug therapy. These studies provide a paradigm for a personalized approach to precision therapy for a disease that heretofore has no therapy

Monitoring recombinant factor VIIa treatment: efficacy depends on high levels of fibrinogen in a model of severe dilutional coagulopathy

OBJECTIVES: Recombinant activated factor VII (rFVIIa) is increasingly being given to treat massive bleeding. However, there is no clear guidance on which patients are suitable for treatment and how the effects of treatment should be monitored. The aim of this in vitro study was to assess the coagulation status of severely hemodiluted blood samples before and after treatment with therapeutic doses of rFVIIa and/or fibrinogen with 2 viscoelastic point-of-care coagulation analyzers: ROTEM (Pentapharm GmbH, Munich, Germany) and Sonoclot (Sienco Inc, Arvada, CO). DESIGN: Laboratory study. SETTING: Research coagulation laboratory. PARTICIPANTS: Ten healthy male volunteers without hereditary or acquired coagulation disorders. INTERVENTIONS: Blood samples were obtained. After severe hemodilution with albumin 5%, therapeutic doses of rFVIIa and/or fibrinogen were added, and the coagulation status was assessed with new 1:1,000 diluted tissue factor-activated tests from ROTEM and Sonoclot. MEASUREMENTS AND MAIN RESULTS: The administration of therapeutic doses of rFVIIa to hemodiluted samples shortened the initiation phase of coagulation only. Isolated fibrinogen administration to physiologic levels improved both the initiation of coagulation as well as clot formation and strength. Combined fibrinogen and rFVIIa administration further improved both effects. CONCLUSIONS: ROTEM and Sonoclot were able to monitor the effects of rFVIIa and fibrinogen administration with 1:1,000 diluted tissue factor-activated tests. The efficacy of rFVIIa was largely dependent on the presence of high levels of fibrinogen in reversing this severe dilutional coagulopathy

Restoration and reversible expansion of the osteoblastic hematopoietic stem cell niche after marrow radioablation

Adequate recovery of hematopoietic stem cell (HSC) niches after cytotoxic conditioning regimens is essential to successful bone marrow transplantation. Yet, very little is known about the mechanisms that drive the restoration of these niches after bone marrow injury. Here we describe a profound disruption of the marrow microenvironment after lethal total body irradiation of mice that leads to the generation of osteoblasts restoring the HSC niche, followed by a transient, reversible expansion of this niche. Within 48 hours after irradiation, surviving host megakaryocytes were observed close to the endosteal surface of trabecular bone rather than in their normal parasinusoidal site concomitant with an increased stromal-derived factor-1 level. A subsequent increase in 2 megakaryocyte-derived growth factors, platelet-derived growth factor-β and basic fibroblast growth factor, induces a 2-fold expansion of the population of N-cadherin-/osteopontin-positive osteoblasts, relative to the homeostatic osteoblast population, and hence, increases the number of potential niches for HSC engraftment. After donor cell engraftment, this expanded microenvironment reverts to its homeostatic state. Our results demonstrate the rapid recovery of osteoblastic stem cell niches after marrow radioablation, provide critical insights into the associated mechanisms, and suggest novel means to manipulate the bone marrow microenvironment to promote HSC engraftment

Cannabidiol Limits T Cell-Mediated Chronic Autoimmune Myocarditis: Implications to Autoimmune Disorders and Organ Transplantation.

Myocarditis is a major cause of heart failure and sudden cardiac death in young adults and adolescents. Many cases of myocarditis are associated with autoimmune processes in which cardiac myosin is a major autoantigen. Conventional immunosuppressive therapies often provide unsatisfactory results and are associated with adverse toxicities during the treatment of autoimmune myocarditis. Cannabidiol (CBD) is a nonpsychoactive constituent of marijuana that exerts antiinflammatory effects independent of classical cannabinoid receptors. Recently, 80 clinical trials have investigated the effects of CBD in various diseases from inflammatory bowel disease to graft versus host disease. CBD-based formulations are used for the management of multiple sclerosis in numerous countries, and CBD also received U.S. Food and Drug Administration approval for the treatment of refractory childhood epilepsy and glioblastoma multiforme. Herein, using a well-established mouse model of experimental autoimmune myocarditis (EAM) induced by immunization with cardiac myosin emmulsified in adjuvant resulting in T cell-mediated inflammation, cardiomyocyte cell death, fibrosis and myocardial dysfunction, we studied the potential beneficial effects of CBD. EAM was characterized by marked myocardial T-cell infiltration, profound inflammatory response and fibrosis (measured by quantitative real-time polymerase chain reaction, histology and immunohistochemistry analyses) accompanied by marked attenuation of both systolic and diastolic cardiac functions measured with a pressure-volume conductance catheter technique. Chronic treatment with CBD largely attenuated the CD3 <sup>+</sup> and CD4 <sup>+</sup> T cell-mediated inflammatory response and injury, myocardial fibrosis and cardiac dysfunction in mice. In conclusion, CBD may represent a promising novel treatment for managing autoimmune myocarditis and possibly other autoimmune disorders and organ transplantation

Metabolic factors and blood cancers among 578,000 adults in the metabolic syndrome and cancer project (Me-Can)

We investigated associations between metabolic factors and blood cancer subtypes. Data on body mass index (BMI), blood pressure, blood glucose, total cholesterol, and triglycerides from seven prospective cohorts were pooled (n = 578,700; mean age = 44 years). Relative risks of blood cancers were calculated from Cox regression models. During mean follow-up of 12 years, 2,751 incident and 1,070 fatal cases of blood cancers occurred. Overall, higher BMI was associated with an increased blood cancer risk. In gender-specific subgroup analyses, BMI was positively associated with blood cancer risk (p = 0.002), lymphoid neoplasms (p = 0.01), and Hodgkin's lymphoma (p = 0.02) in women. Further associations with BMI were found for high-grade B-cell lymphoma (p = 0.02) and chronic lymphatic leukemia in men (p = 0.05) and women (p = 0.01). Higher cholesterol levels were inversely associated with myeloid neoplasms in women (p = 0.01), particularly acute myeloid leukemia (p = 0.003), and glucose was positively associated with chronic myeloid leukemia in women (p = 0.03). In men, glucose was positively associated with risk of high-grade B-cell lymphoma and multiple myeloma, while cholesterol was inversely associated with low-grade B-cell lymphoma. The metabolic syndrome score was related to 48 % increased risk of Hodgkin's lymphoma among women. BMI showed up as the most consistent risk factor, particularly in women. A clear pattern was not found for other metabolic factors