ABSTRACT
Adipose tissue macrophages (ATMs) influence obesity-associated metabolic dysfunction, but the mechanisms by which they do so are not well understood. We show that miR-6236 is a bona fide miRNA that is secreted by ATMs during obesity. Global or myeloid cell-specific deletion of miR-6236 aggravates obesity-associated adipose tissue insulin resistance, hyperglycemia, hyperinsulinemia, and hyperlipidemia. miR-6236 augments adipocyte insulin sensitivity by inhibiting translation of negative regulators of insulin signaling, including PTEN. The human genome harbors a miR-6236 homolog that is highly expressed in the serum and adipose tissue of obese people. hsa-MIR-6236 expression negatively correlates with hyperglycemia and glucose intolerance, and positively correlates with insulin sensitivity. Together, our findings establish miR-6236 as an ATM-secreted miRNA that potentiates adipocyte insulin signaling and protects against metabolic dysfunction during obesity.
Subject(s)
Adipocytes , Hyperglycemia , Insulin Resistance , Insulin , MicroRNAs , Obesity , PTEN Phosphohydrolase , Signal Transduction , MicroRNAs/metabolism , MicroRNAs/genetics , Obesity/metabolism , Obesity/genetics , Animals , Adipocytes/metabolism , Hyperglycemia/metabolism , Hyperglycemia/genetics , Humans , Insulin/metabolism , Insulin Resistance/genetics , Mice , Male , PTEN Phosphohydrolase/metabolism , PTEN Phosphohydrolase/genetics , Mice, Inbred C57BL , Macrophages/metabolism , Adipose Tissue/metabolism , Myeloid Cells/metabolism , Mice, Knockout , Hyperinsulinism/metabolism , Hyperinsulinism/geneticsABSTRACT
This study investigated reading comprehension, reading speed, and the quality of eye movements while reading on an iPad, as compared to printed text. 31 visually-normal subjects were enrolled. Two of the passages were read from the Visagraph standardized text on iPad and Print. Eye movement characteristics and comprehension were evaluated. Mean (SD) fixation duration was significantly longer with the iPad at 270 ms (40) compared to the printed text (p=0.04) at 260 ms (40). Subjects' mean reading rates were significantly lower on the iPad at 294 words per minute (wpm) than the printed text at 318 wpm (p=0.03). The mean (SD) overall reading duration was significantly (p=0.02) slower on the iPad that took 31 s (9.3) than the printed text at 28 s (8.0). Overall reading performance is lower with an iPad than printed text in normal individuals. These findings might be more consequential in children and adult slower readers when they read using iPads.
