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Left ventricular hypertrophy is an independent risk factor in diabetic patients. TGR5 is shown to express in hearts, but its functional role in diabetes-induced cardiac hypertrophy remained unclear. The current study investigated the role of TGR5 on high glucose-induced hypertrophy of H9C2 cells. After incubation with a high level of glucose, H9C2 cells showed hypertrophic responses. Activation of TGR5 by lithocholic acid (LCA) ameliorated cell hypertrophy and enhanced SERCA2a and phosphorylated phospholamban (PLN) expression in H9C2 cells. Triamterene inhibited these effects at an effective dose to block TGR5. However, LCA failed to modify the free radical elevation induced by high-glucose in the H9c2 cells. Moreover, PKA inhibitors, but not an Epac blocker, markedly improved hyperglycemia-induced hypertrophy and attenuated the increased SERCA2a expression by LCA; it also attenuated the phosphorylated PLN and SERCA2a protein expression levels in high glucose-treated H9C2 cells. In conclusion, TGR5 activation stimulated protein kinase A (PKA) to enhance PLN phosphorylation, which activated SERCA2a to remove Ca2+ from cytosol to sarcoplasmic reticulum in addition to the reduction of calcineurin/NFAT pathway signaling to ameliorate the hyperglycemia-induced cardiac hypertrophy shown in cardiomyocytes. TGR5 may service as a new target in the control of diabetic cardiomyopathy.

Two rare N-β-D-glucopyranosyl-1H-indole-3-acetic acid conjugates, N-[2-(1-β-D-glucopyranosyl)-1H-indol-3-yl)acetyl]-L-glutamic acid (1) and N-[2-(1-β-D-glucopyranosyl)-1H-indol-3-yl)acetyl]-L-aspartic acid (2) were isolated from Ginkgo biloba. The structures were elucidated by analyses of HRMS and NMR spectroscopic data. In addition, a simplified and efficient synthetic route for compounds 1 and 2 is also disclosed to determine the absolute configurations of them. This concise syntheses of compounds 1 and 2 may facilitate studies of the biology of this type alkaloids. Compounds 1 and 2 were also tested for their cytotoxic and anti-inflammatory activities. The biological evaluation showed that compounds 1 and 2 led to the decrease of interleukin (IL)-6, nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 at mRNA level in lipopolysaccharide (LPS)-stimulated murine macrophage RAW264.7 cells.

Metastasis-associated recurrence is the main cause for the poor prognosis of hepatocellular carcinoma (HCC). However, the detailed molecular mechanisms underlying HCC metastasis remain elusive. Though some data indicated the oncogenic role of Sorcin in tumors, the prognostic value and biological role of Sorcin in HCC is still unknown. In this study, it demonstrated that Sorcin expression levels were significantly upregulated in HCC tumor tissues compared with matched adjacent nontumorous liver tissues and normal liver tissues, and such expression level correlated with HCC metastasis. High Sorcin expression was significantly correlated with aggressive clinicopathological characteristics such as multiple tumor nodules, high Edmondson-Steiner grade, microvascular invasion, advanced TNM stage and advanced BCLC stage (all P

Proteins, covalently modified by catechol estrogens (CEs), were identified recently from the blood serum of diabetic patients and referred to as estrogenized proteins. Estrogenization of circulating insulin may occur and affect its molecular functioning. Here, the chemical reactivity of CEs towards specific amino acid residues of proteins and the structural and functional changes induced by the estrogenization of insulin were studied using cyclic voltammetry, liquid chromatography-mass spectrometry, circular dichroism spectroscopy, molecular modeling, and bioassays. Our results indicate that CEs, namely, 2- and 4-hydroxyl estrogens, were thermodynamically and kinetically more reactive than the catechol moiety. Upon co-incubation, intact insulin formed a substantial number of adducts with one or multiple CEs via covalent conjugation at its Cys 7 in the A or B chain, as well as at His10 or Lys29 in the B chain. Such conjugation was coupled with the cleavage of inter-chain disulfide linkages. Estrogenization on these sites may block the receptor-binding pockets of insulin. Insulin signaling and glucose uptake levels were lower in MCF-7 cells treated with modified insulin than in cells treated with native insulin. Taken together, our findings demonstrate that insulin molecules are susceptible to active estrogenization, and that such modification may alter the action of insulin.