It also implicates the importance of axonal transport dysfunction in the process of neurodegeneration. These results may have relevance for understanding patho-physiological mechanisms involved in pseudotumor cerebri, syringomyelia, hydrocephalus and glaucoma diseases characterised by fluctuating pressure changes. (C) 2011 Elsevier B.V. All rights reserved.”
“Aims/hypothesis Endoplasmic reticulum (ER) stress and the unfolded
protein response (UPR) can regulate insulin secretion, insulin action and in vitro hepatocyte glucose release. The aims of this study were to determine whether chemical agents that induce ER stress regulate glucose production in vivo and to identify a physiological setting in which this may be important.\n\nMethods A pancreatic clamp test was performed GSK923295 Selleck JQ1 in anaesthetised rats, and insulin and glucagon were replaced at basal levels. [6,6-(2)H(2)]Glucose was infused in the absence (CON, n=10) or presence of ER stress-inducing agents, namely, tunicamycin (Tun, n=10) or thapsigargin (Thap, n=10).\n\nResults Arterial insulin, glucagon, corticosterone and NEFA concentrations were constant throughout experiments and not different among groups. After 1 h, the
glucose concentration was significantly increased in Tun and Thap rats (1.5 +/- 0.2 and 2.1 +/- 0.3 mmol/l, respectively; mean +/- SD), but did not change in CON rats. Glucose production increased (p < 0.05) by 11.0 +/- 1.6 and 13.2 +/- 2.2 mu mol kg(-1) min(-1) in Tun and Thap rats, respectively, but did not change in CON rats. When glucose was infused in a fourth group (HYPER) to match the increase in glucose observed in the Tun and Thap rats, glucose production decreased by similar to 22 mu mol kg(-1) min(-1). Liver phosphorylase activity was increased and glycogen decreased IWR-1-endo in the Tun and Thap groups
compared with the CON and HYPER groups. Given that glucose deprivation induces ER stress in cells, we hypothesised that hypoglycaemia, a condition that elicits increased glucose production, would activate the UPR in the liver. Three hour hyperinsulinaemic (5 mU kg(-1) min(-1)) -euglycaemic (EUG, similar to 7.2 mmol/l, n=6) or -hypoglycaemic (HYPO, similar to 2.8 mmol/l, n=6) clamps were performed in conscious rats. Several biochemical markers of the UPR were significantly increased in the liver, but not in kidney or pancreas, in HYPO vs EUG rats.\n\nConclusions/interpretation Based on our findings that the chemical induction of the UPR increased glucose production and that prolonged hypoglycaemia activated the UPR in the liver, we propose that the UPR in the liver may contribute to the regulation of glucose production during prolonged hypoglycaemia.”
“The aim was to study the COX-1 inhibiting efficacy in context with hydroxyl radical scavenging properties of compounds bearing a carboxylic acid and ester function, respectively.