HMGB1 inhibitor glycyrrhizin attenuates intracerebral hemorrhage-induced injury in rats.

Thrombin activates immunocompetent microglia and increases release of inflammatory cytokines under intracerebral hemorrhage (ICH) insults. Also, thrombin injection into the striatum evokes acute necrosis and delayed apoptosis of neurons. A nucleoprotein high-mobility group box 1 (HMGB1) that is released from necrotic cells has been suggested to behave like a cytokine and cause over-facilitation of immune functions. Here we examined the effect of glycyrrhizin, known as an inhibitor of HMGB1, on thrombin-induced injury in rat cortico-striatal slice cultures and in vivo rat ICH model. In slice cultures, thrombin-induced a drastic increase in propidium iodide fluorescence indicating necrotic cell death in the cortical region, and robust shrinkage of the striatal tissue. Glycyrrhizin (10-100 μM) attenuated thrombin-induced cortical injury in a concentration-dependent manner. The protective effect of glycyrrhizin was not mediated by glucocorticoid receptors or modulation of nitric oxide production, but was reversed by exogenous HMGB1 application. The injury induced by a high concentration of HMGB1 was suppressed by glycyrrhizin. In vivo, unilateral injection of type IV collagenase into rat striatum induced ICH associated with brain edema formation, contralateral paralysis and neuron death. Once daily intraperitoneal administration of glycyrrhizin attenuated ICH-induced edema in both the cortex and the basal ganglia, and improved behavioral performance of rats in forelimb placing. Moreover, glycyrrhizin partially but significantly ameliorated ICH-induced neuron loss inside hematoma. These findings suggest that an HMGB1 inhibitor glycyrrhizin is a potential candidate for a remedy for ICH.Thrombin activates immunocompetent microglia and increases release of inflammatory cytokines under intracerebral hemorrhage (ICH) insults. Also, thrombin injection into the striatum evokes acute necrosis and delayed apoptosis of neurons. A nucleoprotein high-mobility group box 1 (HMGB1) that is released from necrotic cells has been suggested to behave like a cytokine and cause over-facilitation of immune functions. Here we examined the effect of glycyrrhizin, known as an inhibitor of HMGB1, on thrombin-induced injury in rat cortico-striatal slice cultures and in vivo rat ICH model. In slice cultures, thrombin-induced a drastic increase in propidium iodide fluorescence indicating necrotic cell death in the cortical region, and robust shrinkage of the striatal tissue. Glycyrrhizin (10-100 μM) attenuated thrombin-induced cortical injury in a concentration-dependent manner. The protective effect of glycyrrhizin was not mediated by glucocorticoid receptors or modulation of nitric oxide production, but was reversed by exogenous HMGB1 application. The injury induced by a high concentration of HMGB1 was suppressed by glycyrrhizin. In vivo, unilateral injection of type IV collagenase into rat striatum induced ICH associated with brain edema formation, contralateral paralysis and neuron death. Once daily intraperitoneal administration of glycyrrhizin attenuated ICH-induced edema in both the cortex and the basal ganglia, and improved behavioral performance of rats in forelimb placing. Moreover, glycyrrhizin partially but significantly ameliorated ICH-induced neuron loss inside hematoma. These findings suggest that an HMGB1 inhibitor glycyrrhizin is a potential candidate for a remedy for ICH

Identification of asthma cases in Japan using health insurance claims data: Positive and negative predictive values of proposed discrimination criteria: A single-center study

Background: Asthma cases have been increasingly investigated using claims data. However, the validity of defining asthma cases using health insurance claims in Japan is unclear. This study aims to assess the positive and negative predictive values of our proposed discrimination criteria for asthma. Methods: We developed discrimination criteria for asthma based on both the International Statistical Classification of Diseases and Related Health Problems (ICD)-10 disease codes for asthma and health insurance claims data for prescriptions and the treatment of asthma. Inclusion criteria were patients aged ≥16 years with at least one health insurance claim from April 2018 to March 2019 in all departments of our hospital. Physician-diagnosed asthma documented in the charts was used as the reference standard. Positive and negative predictive values of the discrimination criteria for physician-diagnosed asthma were estimated and compared with those estimated from discrimination criteria based solely on ICD-10 codes. Results: The new discrimination criteria had a high positive predictive value (PPV) of 86.0%, which was significantly higher than the PPV for the criteria defined solely by the ICD-10 codes (61.5%) (P < 0.01). The negative predictive values for both criteria were 100%. Allergic rhinitis and chronic cough were frequently misclassified as asthma using the discrimination criteria based solely on ICD-10 codes but were more likely to be appropriately classified using our proposed criteria. Conclusions: Our proposed criteria adequately identified asthma subjects using health insurance claims data in Japan with a high PPV. Further studies are needed for external validation of these criteria