Yoriko Heianza has completed her PhD from University of Tsukuba and has been conducting Post-doctoral studies in Tulane University School of Public Health and Tropical Medicine. She has published more than 30 papers in peer-reviewed medical journals.
Taurine metabolism disturbance is closely linked to obesity, insulin resistance and diabetes. Previous evidence suggested the preventative effects of taurine on diabetes might be through regulating the expression levels of diabetes related genes. In current study, we aimed to estimate whether blood taurine levels modify the overall genetic susceptibility to diabetes on improvement of insulin sensitivity in a randomized dietary trial. We analyzed data from 711 overweight or obese participants (80% Caucasians) who had genetic variants as well as blood taurine levels measured, from the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) trial, a 2-year weight-loss dietary intervention trial. We calculated a genetic risk score (GRS) based on 31 diabetes-associated variants, and estimated the long-term (2 years) improvements of glycemic control traits. We found that baseline plasma taurine levels significantly modified the effects of diabetes GRS on changes in fasting glucose, insulin, and homeostatic model assessment of insulin resistance (HOMA-IR) over 2-year diet interventions (P for interaction = 0.04, 0.01, 0.002, respectively), regardless of weight loss. High baseline taurine levels were associated with a less reduction in both fasting glucose and HOMA-IR among the participants with the lowest tertile of diabetes GRS (both P=0.02), and with a greater reduction in both insulin and HOMA-IR among those with the highest tertile of diabetes GRS (both P=0.04). Our data suggest that blood taurine levels might differentially modulate the genetic effects of diabetes on improvement of insulin sensitivity among overweight/obese patients on weight-loss diets.
Chihiro Mitsui was graduated from Hokkaido University in 2008. After completing initial Clinical Residency Program, she has working as a Research Fellow at Sagamihara National Hospital Clinical Research Center. She has published more than 10 papers in reputed journals.
Background: Aspirin exacerbated respiratory disease (AERD) is characterized by respiratory reactions upon ingestion of cyclooxygenase (COX)-1 inhibitors and cysteinyl leukotriene (cysLT) overproduction. This hypersensitivity reaction is induced by aspirin at low doses that irreversibly inhibit COX-1 in platelets but not COX-2 in endothelial cells and leukocytes. Method: First, platelet activation markers [the expression levels of P-selectin (CD62P), CD63, CD69, and GPIIb/IIIa (PAC-1) in peripheral platelets, the percentage of circulating platelet adherent leukocytes and the levels of plasma soluble P-selectin (sP-selectin) and soluble CD40 ligand (sCD40L)] were examined in stable patients with AERD (n=30), aspirin tolerant asthma (ATA; n=21) and idiopathic chronic eosinophilic pneumonia (CEP; n=10). Furthermore, the levels of plasma sP-selectin and sCD40L in AERD (n=24) and ATA patients (n=7) and surface markers on platelets in AERD patients (n=8) were also assessed during the aspirin challenge test. Results: In stable condition, the expression levels of all surface markers on platelets (P-selectin, P=0.022; CD63, P=0.001; CD69, P=0.029; and PAC-1, P=0.014), the percentage of platelet adherent eosinophils (P=0.025) and the levels of plasma sP-selectin (P=0.017) and sCD40L (P=0.013) were significantly higher in AERD patients than in ATA patients. The expression levels of CD63 and CD69 on platelets and the plasma sCD40L level in AERD patients were higher than those in CEP patients (P<0.001, P=0.008, and P=0.028, respectively). In contrast, there were no significant differences in the expression levels of these markers among ATA patients, CEP patients and controls. In the aspirin challenge test, the levels of platelet activation markers did not change both in AERD and ATA patients. P-selectin and CD63 expressions on platelets and plasma sP-selectin and sCD40L levels positively correlated with the percentage of platelet adherent eosinophils. Among these markers, p-selectin expression and plasma sP-selectin levels positively correlated with urinary leukotriene E4 concentration. Additionally, plasma sP-selectin and sCD40L levels negatively correlated with lung function. Conclusions: Peripheral platelets were activated to greater extent in stable AERD patients than in stable ATA patients, CEP patients and controls. Platelet activation was involved in cysLT overproductions and persistent airflow limitations in AERD in stable disease condition.