Insulin acutely activates metabolism of primary human monocytes and promotes a proinflammatory phenotype.

Increased glycolysis is a metabolic trait of activated innate immune cells and supports functional changes including cytokine production. Insulin drives glycolysis in nonimmune cells, yet its metabolic effects on human innate immune cells remain unexplored. Potential effects of insulin on immune cell metabolism may occur acutely after a postprandial increase in plasma insulin levels or as a consequence of chronically elevated insulin levels as observed in obese insulin-resistant individuals and patients with diabetes.

PET imaging during hypoglycaemia to study adipose tissue metabolism.

Background: Disturbances in adipose tissue glucose uptake may play a role in the pathogenesis of type 2 diabetes, yet its examination by 2-deoxy-2-[ F]fluorodeoxyglucose ([ F]FDG) PET/CT is challenged by relatively low uptake kinetics. We tested the hypothesis that performing [ F]FDG PET/CT during a hypoglycaemic clamp would improve adipose tissue tracer uptake to allow specific comparison of adipose tissue glucose handling between people with or without type 2 diabetes.

Design: We enrolled participants with or without diabetes who were at least overweight, to undergo a hyperinsulinaemic hypoglycaemic clamp or a hyperinsulinaemic euglycaemic clamp (n = 5 per group).

and Effects of Lactate on Metabolism and Cytokine Production of Human Primary PBMCs and Monocytes.

Lactate, the end product of anaerobic glycolysis, is produced in high amounts by innate immune cells during inflammatory activation. Although immunomodulating effects of lactate have been reported, evidence from human studies is scarce. Here we show that expression of genes involved in lactate metabolism and transport is modulated in human immune cells during infection and upon inflammatory activation with TLR ligands , indicating an important role for lactate metabolism in inflammation.

Increased Adipocyte Size, Macrophage Infiltration, and Adverse Local Adipokine Profile in Perirenal Fat in Cushing's Syndrome.

Objective: To analyze changes in fat cell size, macrophage infiltration, and local adipose tissue adipokine profiles in different fat depots in patients with active Cushing's syndrome.

Methods: Subcutaneous (SC) and perirenal (PR) adipose tissue of 10 patients with Cushing's syndrome was compared to adipose tissue of 10 gender-, age-, and BMI-matched controls with regard to adipocyte size determined by digital image analysis on hematoxylin and eosin stainings, macrophage infiltration determined by digital image analysis on CD68 stainings, and adipose tissue leptin and adiponectin levels using fluorescent bead immunoassays and ELISA techniques.

Results: Compared to the controls, mean adipocyte size was larger in PR adipose tissue in patients.

Proinflammatory Effects of Hypoglycemia in Humans With or Without Diabetes.

Severe hypoglycemic events have been associated with increased cardiovascular mortality in patients with diabetes, which may be explained by hypoglycemia-induced inflammation. We used ex vivo stimulations of peripheral blood mononuclear cells (PBMCs) and monocytes obtained during hyperinsulinemic-euglycemic (5.0 mmol/L)-hypoglycemic (2.

Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies.

Hypoglycemia is the most frequent complication of insulin therapy in patients with type 1 diabetes. Since the brain is reliant on circulating glucose as its main source of energy, hypoglycemia poses a threat for normal brain function. Paradoxically, although hypoglycemia commonly induces immediate decline in cognitive function, long-lasting changes in brain structure and cognitive function are uncommon in patients with type 1 diabetes.