Magnesium isoglycyrrhizinate alleviates fructose-induced liver oxidative stress and inflammatory injury through suppressing NOXs.

Excessive fructose intake is a risk factor for liver oxidative stress injury. Magnesium isoglycyrrhizinate as a hepatoprotective agent is used to treat liver diseases in clinic. However, its antioxidant effects and the underlying potential mechanisms are still not clearly understood. In this study, magnesium isoglycyrrhizinate was found to alleviate liver oxidative stress and inflammatory injury in fructose-fed rats. Magnesium isoglycyrrhizinate suppressed hepatic reactive oxygen species overproduction (0.97 ± 0.04 a.u. versus 1.34 ± 0.07 a.u.) in fructose-fed rats by down-regulating mRNA and protein levels of nicotinamide adenine dinucleotide phosphate oxidase (NOX) 1, NOX2 and NOX4, resulting in reduction of interleukin-1ß (IL-1ß) levels (1.13 ± 0.09 a.u. versus 1.97 ± 0.12 a.u.). Similarly, magnesium isoglycyrrhizinate reduced reactive oxygen species overproduction (1.07 ± 0.02 a.u. versus 1.35 ± 0.06 a.u.) and IL-1ß levels (1.14 ± 0.09 a.u. versus 1.66 ± 0.07 a.u.) in fructose-exposed HepG2 cells. Furthermore, data from treatment of reactive oxygen species inhibitor N-acetyl-L-cysteine or NOXs inhibitor diphenyleneiodonium in fructose-exposed HepG2 cells showed that fructose enhanced NOX1, NOX2 and NOX4 expression to increase reactive oxygen species generation, causing oxidative stress and inflammation, more importantly, these disturbances were significantly attenuated by magnesium isoglycyrrhizinate. The molecular mechanisms underpinning these effects suggest that magnesium isoglycyrrhizinate may inhibit NOX1, NOX2 and NOX4 expression to reduce reactive oxygen species generation, subsequently prevent liver oxidative stress injury under high fructose condition. Thus, the blockade of NOX1, NOX2 and NOX4 expression by magnesium isoglycyrrhizinate may be the potential therapeutic approach for improving fructose-induced liver injury in clinic.

Magnesium isoglycyrrhizinate ameliorates fructose-induced podocyte apoptosis through downregulation of miR-193a to increase WT1.

High fructose intake is a risk of glomerular podocyte dysfunction. Podocyte apoptosis has emerged as a major cause of podocyte loss, exacerbating proteinuria. Magnesium isoglycyrrhizinate (MgIG) is usually used as a hepatoprotective agent in clinic. Liver and kidney injury often occurs in human diseases. Recent report shows that MgIG improves kidney function. In this study, we found that MgIG significantly alleviated kidney dysfunction, proteinuria and podocyte injury in fructose-fed rats. It also restored fructose-induced podocyte apoptosis in rat glomeruli and cultured differentiated podocytes. Of note, high-expression of miR-193a, downregulation of Wilms' tumor protein (WT1) and RelA, as well as upregulation of C-Maf inducing protein (C-mip) were observed in these animal and cell models. The data from the transfection of miR-193a mimic, miR-193a inhibitor, WT1 siRNA or LV5-WT1 in cultured differentiated podocytes showed that fructose increased miR-193a to down-regulate WT1, and subsequently activated C-mip to suppress RelA, causing podocyte apoptosis. These disturbances were significantly attenuated by MgIG. Taken together, these results provide the first evidence that MgIG restrains fructose-induced podocyte apoptosis at least partly through inhibiting miR-193a to upregulate WT1, supporting the application of MgIG with a novel mechanism-of-action against podocyte apoptosis associated with fructose-induced kidney dysfunction.

Magnesium isoglycyrrhizinate ameliorates high fructose-induced liver fibrosis in rat by increasing miR-375-3p to suppress JAK2/STAT3 pathway and TGF-ß1/Smad signaling.

Increasing evidence has demonstrated that excessive fructose intake induces liver fibrosis. Epithelial-mesenchymal transition (EMT) driven by transforming growth factor-ß1 (TGF-ß1)/mothers against decapentaplegic homolog (Smad) signaling activation promotes the occurrence and development of liver fibrosis. Magnesium isoglycyrrhizinate is clinically used as a hepatoprotective agent to treat liver fibrosis, but its underlying molecular mechanism has not been identified. Using a rat model, we found that high fructose intake reduced microRNA (miR)-375-3p expression and activated the janus-activating kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) cascade and TGF-ß1/Smad signaling, which is consistent with the EMT and liver fibrosis. To further verify these observations, BRL-3A cells and/or primary rat hepatocytes were exposed to high fructose and/or transfected with a miR-375-3p mimic or inhibitor or treated with a JAK2 inhibitor, and we found that the low expression of miR-375-3p could induce the JAK2/STAT3 pathway to activate TGF-ß1/Smad signaling and promote the EMT. Magnesium isoglycyrrhizinate was found to ameliorate high fructose-induced EMT and liver fibrosis in rats. More importantly, magnesium isoglycyrrhizinate increased miR-375-3p expression to suppress the JAK2/STAT3 pathway and TGF-ß1/Smad signaling in these animal and cell models. This study provides evidence showing that magnesium isoglycyrrhizinate attenuates liver fibrosis associated with a high fructose diet.

Dataset on assessment of magnesium isoglycyrrhizinate injection for dairy diet and body weight in fructose-induced metabolic syndrome of rats.

The data presented herein are related to the research article entitled "Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder" (Zhao et al., 2017) [1]. This article describes the effects of magnesium isoglycyrrhizinate on 24-h food or water intake in fructose-fed rats at 15-week. In addition, this article expands the effect of magnesium isoglycyrrhizinate on the animal body weight change during 1-17 week. The field dataset is made publicly available to enable critical or extended analyzes.

Synthesis of tigogenin MeON-Neoglycosides and their antitumor activity.

To discover new potent cytotoxic steroidal saponins, a series of tigogenin neoglycosides were synthesized via oxyamine neoglycosylation for the first time. The preliminary bioassays for their in vitro antitumor activities against five human cancer cell lines (A375, A-549, HCT-116, HepG2 and MCF-7) were conducted. The results revealed a sugar-dependent activity profile of their cytotoxicity, the glycoconjugation converted the non-active tigogenin to the most potential product Tg29 ((3R)-N-methoxyamino-tigogenin-ß-2-deoxy-d-galactoside) with IC50 value of 2.7µM and 4.6µM against HepG2 and MCF-7 cells respectively. And the 3R-tigogenin neoglycosides exhibited enhanced antitumor activity while the 3S-tigogenin almost showed no activity. Among the five cell lines, HepG2 and MCF-7 cells showed more sensitive cytotoxic responses to the products. Therefore, the neoglycosylation could be a promising strategy for the synthesis of antitumor steroidal saponins and it also proved the essential role of carbohydrate moiety of steroidal saponins in the biological activity.

Magnesium isoglycyrrhizinate blocks fructose-induced hepatic NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder.

Magnesium isoglycyrrhizinate as a hepatoprotective agent possesses immune modulation and anti-inflammation, and treats liver diseases. But its effects on immunological-inflammatory and metabolic profiles for metabolic syndrome with liver injury and underlying potential mechanisms are not fully understood. In this study, magnesium isoglycyrrhizinate alleviated liver inflammation and lipid accumulation in fructose-fed rats with metabolic syndrome. It also suppressed hepatic inflammatory signaling activation by reducing protein levels of phosphorylation of nuclear factor-kappa B p65 (p-NF-κB p65), inhibitor of nuclear factor kappa-B kinase α/ß (p-IKKα/ß) and inhibitor of NF-κB α (p-IκBα) as well as nucleotide-binding domain (NOD)-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein (ASC) and Caspase-1 in rats, being consistent with its reduction of interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and IL-6 levels. Furthermore, magnesium isoglycyrrhizinate modulated lipid metabolism-related genes characterized by up-regulating peroxisome proliferator-activated receptor-α (PPAR-α) and carnitine palmitoyl transferase-1 (CPT-1), and down-regulating sensor for fatty acids to control-1 (SREBP-1) and stearoyl-CoA desaturase 1 (SCD-1) in the liver of fructose-fed rats, resulting in the reduction of triglyceride and total cholesterol levels. These effective actions were further confirmed in fructose-exposed BRL-3A and HepG2 cells. The molecular mechanisms underpinning these observations suggest that magnesium isoglycyrrhizinate may inhibit NF-κB/NLRP3 inflammasome activation to reduce immunological-inflammatory response, which in turn may prevent liver lipid metabolic disorder and accumulation under high fructose condition. Thus, blockade of NF-κB/NLRP3 inflammasome activation and lipid metabolism disorder by magnesium isoglycyrrhizinate may be the potential therapeutic approach for improving fructose-induced liver injury with metabolic syndrome in clinic.

Emodin prevents intima thickness via Wnt4/Dvl-1/beta-catenin signaling pathway mediated by miR-126 in balloon-injured carotid artery rats

Neointimal proliferation after vascular injury is a key mechanism of restenosis, a major cause of percutaneous transluminal angioplasty failure and artery bypass occlusion. Emodin, an anthraquinone with multiple physiological activities, has been reported to inhibit proliferation of vascular smooth muscle cells (VSMCs) that might cause intimal arterial thickening. Thus, in this study, we established a rat model of balloon-injured carotid artery and investigated the therapeutic effect of emodin and its underlying mechanism. Intimal thickness was analyzed by hematoxylin and eosin staining. Expression of Wnt4, dvl-1, beta-catenin and collagen was determined by immunohistochemistry and/or western blotting. The proliferation of VSMC was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and electron microscopy. MicroRNA levels were quantified by real-time quantitative PCR. Emodin relieved injury-induced artery intimal thickness. Results of western blots and immunohistochemistry showed that emodin suppressed expression of signaling molecules Wnt4/Dvl-1/beta-catenin as well as collagen protein in the injured artery. In addition, emodin enhanced expression of an artery injury-related microRNA, miR-126. In vitro, MTT assay showed that emodin suppressed angiotensin II (AngII)-induced proliferation of VSMCs. Emodin reversed AngII-induced activation of Wnt4/Dvl-1/beta-catenin signaling by increasing expression of miR-126 that was strongly supported by transfection of mimic or inhibitor for miR-126. Emodin prevents intimal thickening via Wnt4/Dvl-1/beta-catenin signaling pathway mediated by miR-126 in balloon-injured carotid artery of rats.

Discovery of potent dipeptidyl peptidase IV inhibitors through pharmacophore hybridization and hit-to-lead optimization.

A novel dipeptidyl peptidase IV inhibitor hit (5, IC50=0.86 µM) was structurally derived from our recently disclosed preclinical candidate 4 by replacing the cyanobenzyl with a butynyl based on pharmacophore hybridization. A hit-to-lead optimization effort was then initiated to improve its potency. Most N-substituted analogs exhibited good in vitro activity, and compound 18o (IC50=1.55 nM) was identified to be a potent dipeptidyl peptidase IV inhibitor with a significantly improved pharmacokinetic properties (bioavailablity: 41% vs 82.9%; T1/2: 2h vs 4.9h).

Synthesis of theophylline molecular imprinted polymer microspheres and their properties / 中草药

Objective: To snythesize theophylline molecular imprinted polymer (MIP) microspheres. The influences of reaction conditions, including the category of solvent, reaction time, and the ratio of template to the cross-linking agent on the morphology and adsorption properties of MIP microspheres were studied. Methods: Theophylline MIP microspheres were prepared by precipitation polymerization with theophylline as template and ethyleneglycol dimethacrylate (EGDMA) as cross-linker. The microspheres were characterized by static adsorption and scanning electron microscopy (SEM). Results: The ratio of template to the cross-linking agent was 1:16, reaction time was 24 h, and acetontrile was the solvent. The theophylline MIP microspheres were regular microspheres. The MIP microspheres showed the high adsorption capacity and the partition coefficient of the microspheres adsorbing theophylline was 1.74. Conclusion: Theophylline MIP microspheres have the specific adsorption and recognition capabilities to the theophylline molecules.

Effect of tetramethylpyrazine on the proliferation and collagen synthesis of vascular smooth muscle cells / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the action mechanism of tetramethylpyrazine (TMP) on the proliferation of vascular smooth muscle cells (VSMCs), thus providing experimental evidence for Chinese medicine to effectively prevent restenosis.</p><p><b>METHODS</b>Rats' thoracic aorta VSMCs in vitro cultured (cell line A7r5) were divided into five groups, i.e., the negative control group, the angiotensin II (Ang II, 10(-6) mol/L) group, the low dose TMP (20 micromol/L) plus Ang II group, the middle dose TMP (40 micromol/L) plus Ang II group, the high dose TMP (80 micromol/L) plus Ang II group. The proliferation ratio was detected by MTT. Gene and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, and collagen I and III were detected with real-time fluorescent quantitative PCR and Western blot respectively.</p><p><b>RESULTS</b>Compared with the negative control group, the proliferation ratio of VSMCs obviously increased in the Ang II group (P < 0.05). Compared with the Ang II group, the proliferation ratio of VSMCs obviously decreased in the middle dose TMP plus Ang II group and the high dose TMP plus Ang II group (P < 0.05). Compared with the negative control group, gene and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, Col I, and Col III were obviously up-regulated in the Ang II group (P < 0.05). Compared with the Ang II group, mRNA and protein expressions of Wnt4, Dvl-1, beta-catenin, CyclinD1, Col I, and Col III were obviously down-regulated in the middle dose TMP plus Ang II group and the high dose TMP plus Ang II group (P < 0.05). The aforesaid indices were dose-dependent in the low, middle, and high dose TMP plus Ang II groups.</p><p><b>CONCLUSION</b>TMP inhibited Ang II induced proliferation and collagen secretion of VSMCs through down-regulating Wnt signal pathway.</p>

Relationship between endothelial-to-mesenchymal transition and cardiac fibrosis in acute viral myocarditis / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the relationship between endothelial-to-mesenchymal transition (EndMT) and myocardial fibrosis in acute viral myocarditis (VMC).</p><p><b>METHODS</b>Twenty-eight Balb/c mice were randomized into 3 groups: control group (n=8), VMC group(n=10) and intervention group(n=10). Mice in VMC and intervention groups were injected intraperitoneally(i.p) with single dose of coxsackievirus B3, mice in control group were injected with equal amount of viral-free vehicle. In the following day, mice in control and VMC groups were injected i.p with 0.1 ml of saline and intervention group with 0.1 ml of recombinant human bone morphogenetic protein 7(rh-BMP7) at a concentration of 300 μg/kg. The mice hearts were harvested after 7 d, cardiac collagen volume fraction (CVF) was calculated on picrosirius red-stained sections. mRNA and protein expression of TGF-β1, CD31, VE-cadherin, fibroblast special protein 1 (FSP-1) and α-smooth muscle actin (α-SMA) and collagen 1α1 in myocardiac tissues were detected by real-time RT-PCR and Western blot analysis, respectively.</p><p><b>RESULTS</b>Compared to controls, overt fibrosis was presented in necrotic area of myocardium in VMC group. Meanwhile, marked increase of TGF-β1 expression accompanied with EndMT characterized by loss of endothelial phenotype (decreased expression of CD31 and VE-cadherin), gain of mesenchymal proteins (overexpression of FSP-1 and α-SMA) and increased synthesis of collagen was also demonstrated. Both EndMT and cardiac fibrosis were simultaneously reversed by TGF-β1 inhibition.</p><p><b>CONCLUSION</b>EndMT is involved in cardiac fibrosis in acute viral myocarditis, TGF-β1 might be a main mediator.</p>