Publications by authors named "Hyun-Ju Jang"

The present study was performed to determine the effect of dietary supplementation with processed sulfur on the quality and stability of vacuum packaged pork during aging time. All groups were designated into two groups; NP, a group fed basal diet and SP, a group fed basal diet and processed sulfur, 3 g/kg feed. Following vacuum packaging, muscles were vacuum-packaged and stored under refrigerated condition (1-2℃) for 21 d.

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Impairment of vasodilator action of insulin is associated with endothelial dysfunction and insulin resistance. Activation of Toll-like receptor 4 (TLR4) induces proinflammatory response and endoplasmic reticulum (ER) stress. Saturated fatty acids (SFA) activate TLR4, which induces ER stress and endothelial dysfunction.

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Insulin resistance, a hallmark of metabolic disorders, is a risk factor for diabetes and cardiovascular disease. Impairment of insulin responsiveness in vascular endothelium contributes to insulin resistance. The reciprocal relationship between insulin resistance and endothelial dysfunction augments the pathophysiology of metabolism and cardiovascular functions.

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Epigallocatechin gallate (EGCG) is a major polyphenol in green tea that has beneficial effects in the prevention of cardiovascular disease. Autophagy is a cellular process that protects cells from stressful conditions. To determine whether the beneficial effect of EGCG is mediated by a mechanism involving autophagy, the roles of the EGCG-stimulated autophagy in the context of ectopic lipid accumulation were investigated.

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Obesity is characterized by a chronic proinflammatory state that leads to endothelial dysfunction. Saturated fatty acids (SFA) stimulate Toll-like receptors (TLR) that promote metabolic insulin resistance. However, it is not known whether TLR2 mediates impairment of vascular actions of insulin in response to high-fat diet (HFD) to cause endothelial dysfunction.

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Elevated tissue levels of angiotensin II (ANG II) are associated with impairment of insulin actions in metabolic and cardiovascular tissues. ANG II-stimulated activation of mammalian target of rapamycin (mTOR)/p70 S6 kinase (p70S6K) in cardiovascular tissues is implicated in cardiac hypertrophy and vascular remodeling. However, the role of ANG II-stimulated mTOR/p70S6K in vascular endothelium is poorly understood.

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Pneumatosis cystoides intestinalis (PCI), characterized by presence of intramural gas cyst in the intestinal wall is associated with various medical condition. Polymyosistis, however, is rarely associated with PCI. Few cases are reported in the world, and none has not been reported previously in Korea.

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Endothelial cell dysfunction may play an important role in the development of various vascular diseases, including atherosclerosis. Here we investigated whether lithium chloride (LiCl), an inhibitor of glycogen synthase kinase-3β (GSK-3β), could counteract atherosclerosis induced by a high-fat diet in ApoE⁻/⁻ mice. Ten-week-old male mice were randomly divided into four groups: normal chow diet, high-fat diet (i.

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Background And Aim: To investigate the role of insulin signaling defects in impaired glucose tolerance (IGT), we assessed the functionality of the insulin signaling cascade before and after insulin stimulation in both IGT group and control group.

Methods: Ten IGT subjects and 15 control subjects were recruited for this study. Whole-body insulin-mediated glucose uptake was determined using a euglycemic hyperinsulinemic clamp test.

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Free fatty acids (FFAs) are believed to be a stimulus to elicit beta cell dysfunction. The present study was undertaken to determine whether endoplasmic reticulum (ER) stress was involved in palmitate-induced inhibition of glucose-stimulated insulin secretion (GSIS) and whether reduction of ER stress using a chemical chaperone restored the GSIS-inhibition. Treatment of INS-1 cells with 300 microM palmitate for 24h elicited ER stress, showing increased levels of phospho-eIF2alpha, Bip and spliced XBP, and also induced GSIS-inhibition without reduction of cell viability.

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The extracellular Ca(2+) chelator EGTA and L-type Ca(2+) channel blockers, such as, nifedipine and nimodipine were found to have a protective effect on palmitate-induced MIN6N8a beta cell apoptosis, whereas the Ca(2+) channel opener, Bay K8644, enhanced the apoptotic process. Moreover, the phospho-form of Bad, in conjunction with phospho-Akt, was reduced in response to palmitate and the palmitate-induced dephosphorylations of Akt and Bad were dependent on Ca(2+) influx. The transient expression of catalytically active Akt prevented MIN6N8a cells from palmitate-induced apoptosis.

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Background/aims: The death of endothelial cells may play a critical role in the development of various vascular diseases, including atherosclerosis. While free fatty acids (FFAs) may stimulate endothelial apoptosis, the molecular and cellular mechanisms of this effect have not been studied intensively. To elucidate the mechanisms involved in FFA-induced endothelial cell apoptosis, we investigated the effect of different pharmacological inhibitors on palmitate-induced apoptosis in human umbilical vein endothelial cells (HUVECs).

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EGb 761, a standardized form of Ginkgo biloba L. (Ginkgoaceae) leaf extract, was recently reported to increase pancreatic beta-cell function. To determine whether EGb 761 elicits insulin secretion directly, we treated INS-1 rat beta cells with EGb 761 and then measured insulin release.

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Iron is essential for neoplastic cell growth, and iron chelators have been tested for potential anti-proliferative and anti-cancer effects, but the effects of iron chelators on oral cancer have not been clearly elucidated. To determine the mechanism of cell death induced by iron chelators, we explored the pathways of the three structurally related mitogen-activated protein (MAP) kinase subfamilies during iron chelator-induced apoptosis and differentiation of immortalized human oral keratinocytes (IHOK) and oral cancer cells (HN4). The iron chelator deferoxamine (DFO) exerted potent time- and dose-dependent inhibitory effects on the growth and apoptosis of IHOK and HN4 cells.

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