Yumi Kim

Coix seed extract attenuates the high-fat induced mouse obesity via PPARγ and C/EBPα a downregulation

The seed of the Coix lacryma-jobi L. var. ma-yuen Stapf seed (CLMS) extract has been prescribed to alleviate obesity by practitioners of traditional Korean medicine. Here, we investigated the effect of CLMS extract on PPARγ2 and c/EBPα and obesity responses in C57BL/6J obese mice fed on a high fat diet. The mouse body index, blood profile, and fat accumulation levels in the liver were measured. The protein expression levels of PPARγ2 and c/EBPα in the mice livers were also measured to determine the molecular mode-of-action of the reducing effect of CLMS extract on mouse adipogenesis. The results showed that HFD-induced mouse obesity, fat accumulation, and serum cholesterol were alleviated by the CLMS extract addition. Moreover, PPARγ2 and C/EBPα, proteins, those are related to the adipogenesis, were downregulated by the CLMS extract intake considerably. This study indicates that as a food additive, CLMS extract has a reducing effect on the high-fat diet induced fat accumulation and on body weight through the downregulation of adipogenesis.

Ginkgolide A ameliorates non-alcoholic fatty liver diseases on high fat diet mice

Non-alcoholic fatty liver disease (NAFLD) is one of the most common diseases worldwide and has continuously increased. NAFLD refers to a spectrum of diseases ranging from fatty liver to steatohepatitis, cirrhosis, and even to hepatocyte carcinoma. Excessive fatty acid enters the cell and the mitochondria undergo stress and unremoved ROS can trigger a form of cell apoptosis known as lipoapoptosis. NASH arises from damaged liver hepatocytes due to lipotoxicity. NASH not only involves lipid accumulation and apoptosis but also inflammation. Ginkgo biloba has been tested clinical trials as a traditional medicine for asthma, bronchitis and cardiovascular disease. The effects of Ginkgolide A (GA), derived from the ginkgo biloba leaf, are still unknown in NAFLD. To determine the protective effects of GA in NAFLD, we examined the fatty liver disease condition in the non-esterified fatty acid (NEFA)-induced HepG2 cell line and in a high fat diet mouse model. The findings of this study suggest that GA is non-toxic at high concentrations in hepatocytes. Moreover, GA was found to inhibit cellular lipogenesis and lipid accumulation by causing mitochondrial oxidative stress. GA showed hepatoprotective efficacy by inducing cellular lipoapoptosis and by inhibiting cellular inflammation. The results demonstrated that GA may be feasible as a therapeutic agent for NAFLD patients.

GLP-1 secretion is stimulated by 1,10-phenanthroline via colocalized T2R5 signal transduction in human enteroendocrine L cell

Glucagon-like peptide-1 (GLP-1) hormone is known to regulate blood glucose by an insulinotropic effect and increases proliferation as and also prevents apoptosis of pancreatic β cells. We know that GLP-1 is secreted by nutrients such as fatty acids and sweet compounds but also bitter compounds via stimulation of G-protein coupled receptors (GPCRs) in the gut. Among these, bitter compounds are multiply-contained in phytochemicals or artificial materials and perceived as ligands of various bitter taste receptors. We hypothesized that GLP-1 hormone is secreted through stimulation of a single bitter taste receptor by 1,10-phenanthroline which is known agonist of taste receptor type 2 member 5 (T2R5). To prove this hypothesis, we used the representatively well-known 1,10-phenanthroline as ligand of single receptor and evaluated the existence of T2R5 by double-labeling immunofluorescence and then 1,10-phenanthroline is able to secrete GLP-1 hormone through stimulation of T2R5 in human enteroendocrine cells. Consequently, we verify that GLP-1 hormone is colocalized with T2R5 in the human duodenum and ileum tissue and is secreted by 1,10-phenanthroline via T2R5 signal transduction in differentiated human enteroendocrine L cells.

Anti-Inflammatory Effects of Ginsenoside Rg3 via NF-κB Pathway in A549 Cells and Human Asthmatic Lung Tissue

Objective. There is limited information of the anti-inflammatory effects of Rg3 on inflamed lung cells and tissues. Therefore, we confirmed the anti-inflammatory mechanism of ginsenoside Rg3 in inflamed human airway epithelial cells (A549) and tissues whether Rg3 regulates nuclear factor kappa B (NF-κB) activity. Methods. To induce the inflammation, IL-1β (10u2009ng/ml) was treated to A549 cells for 4u2009h. The effects of Rg3 on NF-κB activity and COX-2 expression were evaluated by western blotting analysis in both IL-1β-induced inflamed A549 cell and human asthmatic airway epithelial tissues. Using multiplex cytokines assay, the secretion levels of NF-κB-mediated cytokines/chemokines were measured. Result. Rg3 showed the significant inhibition of NF-κB activity thereby reduced COX-2 expression was determined in both IL-1β-induced inflamed A549 cell and human asthmatic airway epithelial tissues. In addition, among NF-κB-mediated cytokines, the secretion levels of IL-4, TNF-α, and eotaxin were significantly decreased by Rg3 in asthma tissues. Even though there was no significant difference, IL-6, IL-9, and IL-13 secretion showed a lower tendency compared to saline-treated human asthmatic airway epithelial tissues. Conclusion. The results from this study demonstrate the potential of Rg3 as an anti-inflammatory agent through regulating NF-κB activity and reducing the secretion of NF-κB-mediated cytokines/chemokines.

Proteins derived from Prunus armeniaca kernel are possible to cause Immunoglobulin E reactivity in human sera

Allergic diseases are always caused by protein molecules and in most cases arise in individuals with documented immunologic reactions to foods, pollen, or plant IgE. However, proteins derived from herbal medicine which act as an allergen have not been widely studied. Here, we aim to confirm if the herbal medicine Prunus armeniaca kernel at the proteomic level triggers IgE immunoreactivity. If it does, we can hypothesize what components of protein molecules in the herbal medicine Prunus armeniaca kernel react with and bind to IgE. To test this hypothesis, we utilized proteomic tools and SDS-PAGE stained with Coomassie blue and identified proteins using LC-MS/MS. We also assessed the degree of plasma IgE reactivity in an isolated protein of Prunus armeniaca kernel using western blots of human IgE and an enzyme immunoassay panel, the Allergy-Q test, in 400 human sera. As a result, we found three sera which were positive candidates as Prunus armeniaca kernel IgE binding proteins. The results imply that Prunus armeniaca kernel can act as an allergen given the identification of IgE binding proteins among the isolated proteins of Prunus armeniaca kernel.

Activation of intestinal olfactory receptor stimulates glucagon-like peptide-1 secretion in enteroendocrine cells and attenuates hyperglycemia in type 2 diabetic mice

Odorants are non-nutrients. However, they exist abundantly in foods, wines, and teas, and thus can be ingested along with the other nutrients during a meal. Here, we have focused on the chemical-recognition ability of these ORs and hypothesized that the odorants ingested during a meal may play a physiological role by activating the gut-expressed ORs. Using a human-derived enteroendocrine L cell line, we discovered the geraniol- and citronellal-mediated stimulation of glucagon-like peptide-1 (GLP-1) secretion and elucidated the corresponding cellular downstream signaling pathways. The geraniol-stimulated GLP-1 secretion event in the enteroendocrine cell line was mediated by the olfactory-type G protein, the activation of adenylyl cyclase, increased intracellular cAMP levels, and extracellular calcium influx. TaqMan qPCR demonstrated that two ORs corresponding to geraniol and citronellal were expressed in the human enteroendocrine cell line and in mouse intestinal specimen. In a type 2 diabetes mellitus mouse model (db/db), oral administration of geraniol improved glucose homeostasis by increasing plasma GLP-1 and insulin levels. This insulinotropic action of geraniol was GLP-1 receptor-mediated, and also was glucose-dependent. This study demonstrates that odor compounds can be recognized by gut-expressed ORs during meal ingestion and therefore, participate in the glucose homeostasis by inducing the secretion of gut-peptides.

The therapeutic effects of Yongdamsagan-tang on autoimmune hepatitis models

Autoimmune hepatitis (AIH) is an immunity disorder that is the result of antibodies in the liver tissue of the patient that are attacked by activated immune cells due to an unknown cause. In this study, we aimed to investigate the anti-inflammatory effect of Yongdamsagan-tang (YST) extracts and confirm effects on autoimmune hepatitis models as the therapeutic agent using the YST extracted by various solvents. YST, a mixture of 11 herbal extracts, is known in traditional Korean medicine as a widely used treatment for inflammatory diseases. We proposed the AIH-condition in vitro model by the addition of recombinant IL-17A and then observed several markers linked to AIH symptoms, including an increase of IL-6 expression, lipid accumulation, and fibrosis. In AIH-condition hepatic cell model, YST reduced IL-6 expression and lipid accumulation caused by treatment of IL-17 combination in hepatocyte cells. Also, YST blocked several activated fibrosis factors including transforming growth factor-β (TGF- β1), collagen type 1 (Col-α1(I)), and α-smooth muscle actin (α-SMA) in liver stellate cells. Furthermore, pretreatment with YST protected hepatic damage and reduces histological injury by suppressing apoptosis mediator and inflammatory cytokines expression in concanavalin A (Con A)-induced autoimmune hepatitis mice model. The findings here improve our understanding of YST extracted by 80% ethanol, suggesting that YST can be used as a therapeutic treatment for AIH.

Metabolic Profiling of Liver Tissue in Diabetic Mice Treated with Artemisia Capillaris and Alisma Rhizome Using LC-MS and CE-MS.

Artemisia Capillaris (AC) and Alisma Rhizome (AR) are natural products for the treatment of liver disorders in oriental medicine clinics. Here, we report metabolomic changes in the evaluation of the treatment effects of AC and AR on fatty livers in diabetic mice, along with a proposition of the underlying metabolic pathway. Hydrophobic and hydrophilic metabolites extracted from mouse livers were analyzed using HPLC-QTOF and CE-QTOF, respectively, to generate metabolic profiles. Statistical analysis of the metabolites by PLS-DA and OPLA-DA fairly discriminated between the diabetic, and the AC- and AR-treated mice groups. Various PEs mostly contributed to the discrimination of the diabetic mice from the normal mice, and besides, DG (18:1/16:0), TG (16:1/16:1/20:1), PE (21:0/20:5), and PA (18:0/21:0) were also associated with discrimination by s-plot. Nevertheless, the effects of AC and AR treatment were indistinct with respect to lipid metabolites. Of the 97 polar metabolites extracted from the CE-MS data, 40 compounds related to amino acid, central carbon, lipid, purine, and pyrimidine metabolism, with [Formula: see text] values less than 0.05, were shown to contribute to liver dysregulation. Following treatment with AC and AR, the metabolites belonging to purine metabolism preferentially recovered to the metabolic state of the normal mice. The AMP/ATP ratio of cellular energy homeostasis in AR-treated mice was more apparently increased ([Formula: see text]) than that of AC-treated mice. On the other hand, amino acids, which showed the main alterations in diabetic mice, did not return to the normal levels upon treatment with AR or AC. In terms of metabolomics, AR was a more effective natural product in the treatment of liver dysfunction than AC. These results may provide putative biomarkers for the prognosis of fatty liver disorder following treatment with AC and AR extracts.

Antihyperglycemic and Antiobesity Effects of JAL2 on db/db Mice

Lonicera japonica Thunb. (LJT) and Rehmannia glutinosa Libosch. (RGL) have been used traditionally as a herbal medicine in Korean medicine. Using LC/Q-TOF was performed to profile the two herbal medicines and the mixture of LJR and RGL (JAL2, ratio 1u2009:u20091). We performed oral glucose tolerance test (OGTT) and plasma GLP-1 and insulin secretion by multiplex assays to investigate antidiabetic effects of LJT, RGL, and JAL2 in db/db mice, the mice model of type 2 diabetes mellitus (T2DM). Also, the antiobesity-related factors such as plasma peptide YY (PYY), triglyceride, total cholesterol, HDL, LDL, and weight of liver, epididymal, and retroperitoneal fat tissue were investigated. Through the multiplex assay, it was found that JAL2 treatment more efficiently attenuated high levels of blood glucose by stimulating GLP-1 secretion and reduced LDL concentration and weight of liver and retroperitoneal fat tissue compared to LJT or RGL treated separately. These results suggest that the JAL2 has antidiabetes and antiobesity effects in T2DM mice model.

Anti-lipoapoptotic effects of Alisma orientalis extract on non-esterified fatty acid-induced HepG2 cells

BackgroundLiver steatosis was caused by lipid accumulation in the liver. Alisma orientale (AO) is recognized as a promising candidate with therapeutic efficacy for the treatment of nonalcoholic fatty liver disease (NAFLD). HepG2 hepatocyte cell line is commonly used for liver disease cell model.MethodThe HepG2 cells were cultured with the NEFAs mixture (oleic and palmitic acids, 2:1 ratio) for 24xa0h to induce hepatic steatosis. Then different doses of Alisma orientale extract (AOE) was treated to HepG2 for 24xa0h. Incubated cells were used for further experiments.ResultsThe AOE showed inhibitory effects on lipid accumulation in the Oil Red O staining and Nile red staining tests with no cytotoxicity at a concentration of 300xa0μg/mL. Fatty acid synthase (FASN) and acetyl-CoA carboxylase 1 (ACC1) mRNA and protein expression level were down-regulated after AOE treatment. Bcl-2 associated X protein (Bax) and c-Jun N-terminal kinase (JNK) mRNA expression level were decreased as well as p-JNK (activated form of JNK), Bax, cleaved caspase-9, caspase-3 protein expression level. Anti-apopototic B-cell lymphoma 2 (Bcl-2) protein level increased after AOE treatment. In addition, inflammatory protein expression including p-p65, p65, COX-2 and iNOS were inhibited by AOE treatment.ConclusionThe results suggest that AOE has anti-steatosis effects that involve lipogenesis, anti-lipoapoptosis, and anti-inflammation in the NEFA-induced NAFLD pathological cell model.