이성준 교수

Obesity is caused by an imbalance between caloric intake and energy expenditure and accumulation of excess lipids in adipose tissues. Recent studies have demonstrated that green tea and its processed products (e.g., oolong and black tea) are introduced to exert beneficial effects on lipid metabolism. Here, we propose that fermented green tea (FGT) extract, as a novel processed green tea, exhibits antiobesity effects. FGT reduced body weight gain and fat mass without modifying food intake. mRNA e

The phytochemical composition of carotenoids, tocopherols, free sugars, organic acids, L-ascorbic acid, capsaicinoids, and flavonoids in green and red paprika (GP and RP), and paprika leaves (PL) cultivated in Korea were analyzed. The ethanolic extracts of GP, RP, and PL were obtained with 80% ethanol, and their antioxidative activities were determined by measuring their ABTS and DPPH radical scavenging activities. RP showed the highest contents of capsanthin (58.33 ± 3.91 mg/100 g dry weight) a

SCOPE: This study investigated metabolic effects of ursolic acid (UA), a peroxisome proliferation-activated receptor (PPAR)-α activator, in vivo. METHODS AND RESULTS: High-fat diet (HFD)-fed C57BL/6J mice were orally administered UA (50 or 200 mg/kg body weight) for 8 wk. UA reduced liver and adipose tissue mass, adipocyte size, and plasma leptin concentrations, plasma triglyceride and low-density-lipoprotein cholesterol concentrations, while it elevated the high-density-lipoprotein cholesterol

SCOPE: Taurine, which is abundant in seafood, has antiatherogenic activities in both animals and humans; however, its molecular target has been elusive. We examined whether taurine could activate liver X receptor-α (LXR-α), a critical transcription factor in the regulation of reverse cholesterol transport in macrophages. METHODS AND RESULTS: Taurine bound directly to LXR-α in a reporter gene assay, time-resolved fluorescence resonance energy transfer analysis, and limited protease digestion expe

Olfactory receptors are ectopically expressed in extra-nasal tissues. The gut is constantly exposed to high levels of odorants where ectopic olfactory receptors may play critical roles. Activation of ectopic olfactory receptor 544 (Olfr544) by azelaic acid (AzA), an Olfr544 ligand, reduces adiposity in mice fed a high-fat diet (HFD) by regulating fuel preference to fats. Herein, we investigated the novel function of Olfr544 in the gut. In GLUTag cells, AzA induces the cAMP-PKA-CREB signaling axi

Abstract The microbiota is indispensable for human health and the regulation of various body functions, including energy metabolism. The harmonic crosstalk between the microbiota and the intestinal epithelial barrier determines gut homeostasis and health status in the healthy subject. Obesity and type 2 diabetes risk are, to some extent, explained by alterations in the microbiota. Since recent data indicate that the population of gut microorganisms can influence nutrient absorption and energy st

Cyanidin-3-O-glucoside (C3G) is a natural anthocyanin abundant in fruits and vegetables that interacts and possibly modulates energy metabolism and oxidative stress. This study investigated the effect of C3G on gluconeogenesis and cancer cell senescence. C3G activates adenosine monophosphate-activated protein kinase (AMPK), a cellular energy sensor involved in metabolism and the aging process. C3G suppressed hepatic gluconeogenesis by reducing the expression of gluconeogenic genes through the ph

Dietary flavonoids have various biological functions. However, their cellular transport mechanisms are largely unknown. We have determined that the multidrug and toxic compound extrusion transporter-1 (MATE1) is a membrane transporter for flavonoids and has a high affinity for quercetin. HEK293T cells overexpressing MATE1 exhibited increased intracellular quercetin accumulation. This effect disappeared in the presence of a MATE1 inhibitor and after MATE1 gene knockdown. HepG2 cells expressed MAT

We investigated the acute metabolic effects of isoflavones from Pueraria lobata (Willd.) Ohwi (IPL) in ovariectomized (OVX) mice. After 4 weeks of IPL feeding at 500 mg/day/kg body weight (OVX500), plasma 17β-estradiol concentrations were significantly higher (+25%, p < 0.05), whereas plasma triglyceride levels were significantly lower in OVX mice (-15%, p < 0.05) compared with controls. Abdominal adipose tissue weight was marginally reduced in IPL-fed groups compared with OVX controls and the p

Abstract A branched oligosaccharides (BOS) mixture was produced from liquefied starch solution using a maltogenic amylase of Bacillus licheniformis (BLMA). The BOS mixture was produced by both α‐1,4‐bond hydrolyzing and α‐1,6‐transglycosylation activities of BLMA, and it contained 58.3% of various branched oligosaccharides. Small branched oligosaccharides such as isomaltose, isopanose, and panose were identified in the mixture by various analyses including high performance ion‐chromatography (HP

The prevalence of two major types of skin cancer, melanoma and non-melanoma skin cancer, has been increasing worldwide. Skin cancer incidence is estimated to rise continuously over the next 20 years due to ozone depletion and an increased life expectancy. Chemotherapeutic agents could affect healthy cells, and thus may be toxic to them and cause numerous side effects or drug resistance. Phytochemicals that are naturally occurring in fruits, plants, and herbs are known to possess various bioactiv

Olfactory receptors (ORs) are the largest protein superfamily in mammals. Certain ORs are ectopically expressed in extranasal tissues and regulate cell type-specific signal transduction pathways. OR2AT4 is ectopically expressed in skin cells and promotes wound healing and hair growth. As the capacities of wound healing and hair growth decline with aging, we investigated the role of OR2AT4 in the aging and senescence of human keratinocytes. OR2AT4 was functionally expressed in human keratinocytes

SCOPE: Enzymatically modified rice starch (ERS) synthesized with 4-α-glucanotransferase has a longer structure than rice starch, which could delay digestion, similar to dietary fiber. We investigated the effects of ERS on glucose and lipid metabolism with mice fed a high-fat diet containing ERS (HFD-ERS). METHOD AND RESULTS: Four weeks of ERS feeding showed hypoglycemic effects with a significant reduction in fasting glucose (46%), insulin (57%), and leptin (83%) levels; improved glucose toleran

OBJECTIVES: Postmenopausal obesity is a paramount health concern among older women. Black rice is a well-known pigmented rice variety with a higher anthocyanin content. Both in vitro and in vivo studies have demonstrated the effects of black rice on obesity. The present study aimed to investigate the effects of black rice extract (BRE) on obesity among obese postmenopausal women from Korea. METHODS: This was a 12-week, randomized, double-blind, placebo-controlled preliminary clinical trial. The