IL-10 provides cardioprotection in diabetic myocardial infarction via upregulation of Heme clearance pathways
JCI INSIGHT
Authors: Gupta, Rajesh; Liu, Lijun; Zhang, Xiaolu; Fan, Xiaoming; Krishnamurthy, Prasanna; Verma, Suresh; Tongers, Joern; Misener, Sol; Ashcherkin, Nikita; Sun, Hongliu; Tian, Jiang; Kishore, Raj
Abstract
Diabetes is a risk factor for myocardial infarction, and outcomes after myocardial infarction are worse among diabetics compared with nondiabetics. Diabetes is associated with impaired Heme clearance. Here, we determined whether heme toxicity and impaired heme clearance contribute to diabetic myocardial infarction injury and assessed IL-10 as a therapeutic agent for diabetic myocardial infarction. Plasma-free hemoglobin was significantly elevated in diabetic mice compared with nondiabetic mice after myocardial infarction. Infarct size had strong correlation to the level of plasma-free hemoglobin. Hemoglobin and reactive iron deposition within the infarct zone were also demonstrated in diabetic MI. IL-10 significantly reduced infarct size and improved cardiac function in diabetic mice. Moreover, IL-10 improved capillary density, reduced apoptosis, and decreased inflammation in the border zone of the infarcted hearts, findings that were partially inhibited by Tin protoporphyrin (a heme oxygenase-1 inhibitor). IL-10 upregulated CD163, the hemoglobin:haptoglobin scavenger receptor, and heme oxygenase-1 in THP-1-derived and primary human CD14(+) macrophages. IL-10 significantly protected against ischemic injury when HL-1 cardiomyocytes were cotreated with hemoglobin. Together, our findings indicate that IL-10 is cardioprotective in diabetic myocardial infarction via upregulation of heme clearance pathways. These findings implicate heme clearance as a potentially novel therapeutic direction for diabetic myocardial infarction.
Shikonin Inhibits Der p 2-Induced Cytokine and Chemokine Expression in Dendritic Cells in Patients with Atopic Dermatitis
EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE
Authors: Yen, Chung-Yang; Chiang, Wen-Dee; Liu, Shang-Yong; Yu, Sheng-Jie; Hsieh, Ching-Liang
Abstract
Atopic dermatitis (AD) is a common inflammatory skin disorder. Shikonin, the active component of Lithospermum erythrorhizon extract, exhibits anti-inflammatory effects. The objective of the present study was to investigate the effect of shikonin on proinflammatory cytokines and chemokine in patients with AD. Ten patients with AD who were allergic to house dust mite (HDM) and seven healthy controls were recruited in this study. Peripheral blood mononuclear cells were isolated, and CD14(+) cells were further selected and differentiated to dendritic cells. Dendritic cells stimulated using Der p 2, the major HDM allergen, were cotreated with shikonin for 24 hours, and dexamethasone was used as a control. Culture supernatants were collected, and proinflammatory cytokine and chemokine concentrations were analyzed using a multiplex assay system. Shikonin significantly inhibited Der p 2-induced expression of interleukin (IL)-6, IL-9, and IL-17A; monocyte chemoattractant protein (MCP)-1; macrophage inflammatory protein (MIP)-1 alpha; MIP-1 beta; and Chemokine (C-C motif) ligand 5 (RANTES). The inhibitory effects of shikonin on IL-9, MIP-1 beta, and RANTES expression were stronger than those of dexamethasone. Therefore, Shikonin can be considered a promising drug for AD treatment because it inhibits different inflammatory cytokines expression.