PubMed Health⌕ Search

Biomedical subjects

Hyunsook Kim

Publications and source records attributed to Hyunsook Kim.

5 recordsLinked to original sources

Peroxisome proliferator-activated receptor-alpha agonist treatment in a transgenic model of type 2 diabetes reverses the lipotoxic state and improves glucose homeostasis.

Abnormalities in insulin action are the characteristics of type 2 diabetes. Dominant-negative muscle-specific IGF-I receptor (MKR) mice exhibit elevated lipid levels at an early age and eventually develop type 2 diabetes. To evaluate the role of elevated lipids in the progression of the diabetic state, MKR mice were treated with WY14,643, a peroxisome proliferator-activated receptor (PPAR)-alpha agonist. WY14,643 treatment markedly reduced serum fatty acid and triglyceride levels within a few days, as well as muscle triglyceride levels, and subsequently normalized glucose and insulin levels in MKR mice. Hyperinsulinemic-euglycemic clamp analysis showed that WY14,643 treatment enhanced muscle and adipose tissue glucose uptake by improving whole-body insulin sensitivity. Insulin suppression of endogenous glucose production by the liver of MKR mice was also improved. The expression of genes involved in fatty acid oxidation was increased in liver and skeletal muscle, whereas gene expression levels of hepatic gluconeogenic enzymes were decreased in WY14,643-treated MKR mice. WY14,643 treatment also improved the pattern of glucose-stimulated insulin secretion from the perfused pancreata of MKR mice and reduced the beta-cell mass. Taken together, these findings suggest that the reduction in circulating or intracellular lipids by activation of PPAR-alpha improved insulin sensitivity and the diabetic condition of MKR mice.

Animals↗

Silica-based artificial protease exploiting aldehyde groups as catalytic elements.

An artificial protease synthesized by covering the surface of silica gel with aldehyde and indole groups effectively hydrolyzed albumin and gamma-globulin. It is proposed that the aldehyde group is involved in both complexation of the protein substrate and the catalytic cleavage of the peptide bonds of the complexed proteins.

Aldehydes↗

Inactivation of muscle insulin and IGF-I receptors and insulin responsiveness.

PURPOSE OF REVIEW: This review will outline the recent advances in the area of insulin-stimulated skeletal muscle glucose uptake and its effect on whole body glucose homeostasis, using gene-deletion and transgenic mouse models. RECENT FINDINGS: Insulin resistance is often the first abnormality detected in cases of type 2 diabetes, and is seen at the level of the peripheral tissues especially muscle. Both the insulin receptor and the insulin-like growth factor I receptor are capable of stimulating glucose uptake into skeletal muscle. One model involves the gene deletion of muscle glucose transport protein 4, which leads to severe insulin resistance and hyperglycemia, and a second model using a transgenic approach abrogates the function of the insulin-like growth factor I receptor and the insulin receptor resulting in severe insulin resistance and progression to diabetes. Both models demonstrate that abrogation of the insulin-like growth factor I receptor and the insulin receptor or a common signalling pathway must be inhibited to cause sufficient insulin resistance to lead to type 2 diabetes; with either glucotoxicity or lipotoxicity being involved in the progression from severe to resistance to full-blown type 2 diabetes. SUMMARY: Thus, abrogation of insulin-stimulated glucose uptake in skeletal muscle, at least in mice, may lead to severe insulin resistance and diabetes.

Animals↗