Problems associated with glucose toxicity: Role of hyperglycemia-induced oxidative stress

Abstract

Glucose homeostasis deficiency leads to a chronic increase in blood glucose concentration. In contrast to physiological glucose concentration, chronic superphysiological glucose concentration negatively affects a large number of organs and tissues. Glucose toxicity means a decrease in insulin secretion and an increase in insulin resistance due to chronic hyperglycemia. It is now generally accepted that glucose toxicity is involved in the worsening of diabetes by affecting the secretion of beta-cells. Several mechanisms have been proposed to explain the adverse effects of hyperglycemia. It was found that persistent hyperglycemia caused the functional decline of neutrophils. Infection is thus the main problem resulting from glucose toxicity in the acute phase. In other words, continued hyperglycemia is a life-threatening risk factor, not only in the chronic but also the acute phase, and it becomes a risk factor for infection, particularly in the perioperative period.

Flight is the key to postprandial blood glucose balance in the fruit batsEonycteris spelaeaandCynopterus sphinx

“…Some researchers have pointed that high blood glucose typically increases the formation of unhealthful products in body, and one of typical is glucated hemoglobin (HbA1c), a toxic advanced glycogen end‐products (AGE) (Kilpatrick, 2000; Nathan et al., 2008). The extent of hemoglobin glycation correlates strongly with the level of ambient glycemia during several weeks and HbA1c plays a crucial role in cardiovascular disease and diabetes (Brownlee, 2001; Brunner, Schvartz, Priego‐Capote, Couté, & Sanchez, 2009; Ceriello, 2003; Kawahito, Kitahata, & Oshita, 2009; Nathan, 1996; Suh et al., 2007). However, Kelm's test for HbA1c clarified further that high blood glucose levels in fruit bats do not last very long (Kelm et al., 2011).…”

“…High levels of blood glucose and abnormal blood glucose fluctuations may also increase the number of reactive oxygen species (ROS) (Brownlee, 2001; Buffenstein, Edrey, Yang, & Mele, 2008; Choi, Benzie, Ma, Strain, & Hannigan, 2008; Kawahito et al., 2009). In general, when the level of ROS exceed the normal, it may damage proteins and lipids, even DNA, and it also affects the animal aging and leads to metabolic syndrome and diabetes because of ROS‐induced oxidative stress (Barja, 2002; Brunet‐Rossinni & Austad, 2004; Buffenstein et al., 2008).…”

“…In general, when the level of ROS exceed the normal, it may damage proteins and lipids, even DNA, and it also affects the animal aging and leads to metabolic syndrome and diabetes because of ROS‐induced oxidative stress (Barja, 2002; Brunet‐Rossinni & Austad, 2004; Buffenstein et al., 2008). ROS can also lead to pancreatic β‐cell dysfunction, tissues insulin resistance, and declining insulin production (Brownlee, 2001; Brunner et al., 2009; Kawahito et al., 2009; Vincent, Russell, Low, & Feldman, 2004). Follow this point, fruit bats must have the ability to prevent excess production of ROS or reduce oxidative stress raised by a huge fluctuation of blood glucose (Brunner et al., 2009; Buffenstein et al., 2008; Kawahito et al., 2009; Munshi‐South & Wilkinson, 2010; Vincent et al., 2004).…”

“…ROS can also lead to pancreatic β‐cell dysfunction, tissues insulin resistance, and declining insulin production (Brownlee, 2001; Brunner et al., 2009; Kawahito et al., 2009; Vincent, Russell, Low, & Feldman, 2004). Follow this point, fruit bats must have the ability to prevent excess production of ROS or reduce oxidative stress raised by a huge fluctuation of blood glucose (Brunner et al., 2009; Buffenstein et al., 2008; Kawahito et al., 2009; Munshi‐South & Wilkinson, 2010; Vincent et al., 2004). However, other researchers hold different opinions.…”

Pyrrolidine dithiocarbamate enhances hepatic glycogen synthesis and reduces FoxO1-mediated gene transcription in type 2 diabetic rats

“…Hyperglycemia is the main consequence of this disease. Persistent high level of blood glucose is considered to be a key factor in the development of several chronic complications, such as renal failure, microvasculopathy, and peripheral neuropathy, that contribute to the high morbidity and mortality observed in diabetes (15). A better control of blood glucose reduces diabetic complications sharply (5).…”