Publications by authors named "Young Mi Song"

Impairment in macroautophagy/autophagy flux and inflammasome activation are common characteristics of nonalcoholic steatohepatitis (NASH). Considering the lack of approved agents for treating NASH, drugs that can enhance autophagy and modulate inflammasome pathways may be beneficial. Here, we investigated the novel mechanism of ezetimibe, a widely prescribed drug for hypercholesterolemia, as a therapeutic option for ameliorating NASH.

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Betatrophin/angiopoietin-like protein 8 (ANGPTL8) is a liver-secreted protein recently identified as a potent stimulator of beta cell proliferation in mice. However, it is unclear how betatrophin is regulated in humans with non-alcoholic fatty liver disease (NAFLD). We investigated the role of betatrophin in mice and in humans with and without NAFLD.

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Metformin is known to alleviate hepatosteatosis by inducing 5' adenosine monophosphate (AMP)-kinase-independent, sirtuin 1 (SIRT1)-mediated autophagy. Dysfunctional mitophagy in response to glucolipotoxicities might play an important role in hepatosteatosis. Here, we investigated the mechanism by which metformin induces mitophagy through restoration of the suppressed Parkin-mediated mitophagy.

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Article Synopsis
  • Metformin activates both PRKA and SIRT1, leading to induction of autophagy via PRKA-MTOR-ULK1 or SIRT1-FOXO pathways.
  • In experiments with ob/ob mice, metformin and caloric restriction showed significant improvements in body weight, glucose regulation, and liver fat accumulation.
  • The study suggests that metformin alleviates liver fat buildup independently of PRKA, primarily through SIRT1's role in enhancing autophagy.
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Growing evidence suggests that advanced glycation end-products (AGEs) are cytotoxic to pancreatic β-cells. The aims of this study were to investigate whether glycated albumin (GA), an early precursor of AGEs, would induce dysfunction in pancreatic β-cells and to determine which kinds of cellular mechanisms are activated in GA-induced β-cell apoptosis. Decreased viability and increased apoptosis were induced in INS-1 cells treated with 2.

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Background: Inflammation plays an important role in coronary artery disease from the initiation of endothelial dysfunction to plaque formation to final rupture of the plaque. In this study, we investigated the potential pathophysiological and clinical relevance of novel cytokines secreted from various cells including adipocytes, endothelial cells, and inflammatory cells, in predicting coronary artery disease (CAD) in asymptomatic subjects with type 2 diabetes mellitus.

Methods: We enrolled a total of 70 asymptomatic type 2 diabetic patients without a documented history of cardiovascular disease, and determined serum levels of chemerin, omentin-1, YKL-40, and sCD26.

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Induction of autophagy is known not only to regulate cellular homeostasis but also to decrease triglyceride accumulation in hepatocytes. The aim of this study is to investigate whether DMSO (dimethyl sulfoxide) has a beneficial role in free fatty acid-induced hepatic fat accumulation. In HepG2 cells, treatment with 0.

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Neural stem cell (NSC) transplantation replaces damaged brain cells and provides disease-modifying effects in many neurological disorders. However, there has been no efficient way to obtain autologous NSCs in patients. Given that ectopic factors can reprogram somatic cells to be pluripotent, we attempted to generate human NSC-like cells by reprograming human fibroblasts.

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Cellular oxygen sensing is required for hypoxia-inducible factor-1alpha stabilization, which is important for tumor cell survival, proliferation, and angiogenesis. Here we find that terpestacin, a small molecule previously identified in a screen of microbial extracts, binds to the 13.4-kDa subunit (UQCRB) of mitochondrial Complex III, resulting in inhibition of hypoxia-induced reactive oxygen species generation.

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The function of eukaryotic histone deacetylase (HDAC) has been extensively studied for its critical role in transcriptional regulation and carcinogenesis. However that of the prokaryotic counterpart remains largely unknown. Recently, we cloned HDAC-like protein in Thermus caldophilus GK24 (Tca HDAC) from a genomic library of the microorganism based on homology analysis with human HDAC1.

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Histone deactylases (HDACs) are members of an ancient enzyme family found in eukaryotes as well as in prokaryotes such as archaebacteria and eubacteria. We here report a new histone deacetylase (Tca HDAC) that was cloned from the genomic library of Thermus caldophilus GK24 based on homology analysis with human histone deacetylase1 (HDAC1). The gene contains an open reading frame encoding 375 amino acids with a calculated molecular mass of 42,188 Da and the deduced amino acid sequence of Tca HDAC showed a 31% homology to human HDAC1.

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