naphthoquinones and Fibrosis

Scleroderma is an autoimmune disease caused by the abnormal regulation of extracellular matrix synthesis and is activated by non-regulated inflammatory cells and cytokines. Echinochrome A (EchA), a natural pigment isolated from sea urchins, has been demonstrated to have antioxidant activities and beneficial effects in various disease models. The present study demonstrates for the first time that EchA treatment alleviates bleomycin-induced scleroderma by normalizing dermal thickness and suppressing collagen deposition in vivo. EchA treatment reduces the number of activated myofibroblasts expressing α-SMA, vimentin, and phosphorylated Smad3 in bleomycin-induced scleroderma. In addition, it decreased the number of macrophages, including M1 and M2 types in the affected skin, suggesting the induction of an anti-inflammatory effect. Furthermore, EchA treatment markedly attenuated serum levels of inflammatory cytokines, such as tumor necrosis factor-α and interferon-γ, in a murine scleroderma model. Taken together, these results suggest that EchA is highly useful for the treatment of scleroderma, exerting anti-fibrosis and anti-inflammatory effects.

Topics: Actins; Animals; Anti-Inflammatory Agents; Bleomycin; Collagen; Cytokines; Disease Models, Animal; Fibrosis; Humans; Inflammation Mediators; Macrophages; Male; Mice; Mice, Inbred C57BL; Myofibroblasts; Naphthoquinones; Phosphorylation; RAW 264.7 Cells; Scleroderma, Systemic; Skin; Smad3 Protein; Vimentin

Renal interstitial fibrosis is a common pathological feature of chronic kidney disease that may involve changes of metabolism in kidney cells. In the present study, we first showed that blockade of glycolysis with either dichloroacetate (DCA) or shikonin to target different glycolytic enzymes reduced renal fibrosis in a mouse model of unilateral ureteral obstruction (UUO). Both inhibitors evidently suppressed the induction of fibronectin and collagen type I in obstructed kidneys, with DCA also showing inhibitory effects on collagen type IV and α-smooth muscle actin (α-SMA). Histological examination also confirmed less collagen deposition in DCA-treated kidneys. Both DCA and shikonin significantly inhibited renal tubular apoptosis but not interstitial apoptosis in UUO. Macrophage infiltration after UUO injury was also suppressed. Shikonin, but not DCA, caused obvious animal weight loss during UUO. To determine whether shikonin and DCA worked on tubular cells and/or fibroblasts, we tested their effects on cultured renal proximal tubular BUMPT cells and renal NRK-49F fibroblasts during hypoxia or transforming growth factor-β

Topics: Animals; Apoptosis; Cell Line; Dichloroacetic Acid; Disease Models, Animal; Enzyme Inhibitors; Epithelial Cells; Extracellular Matrix; Fibroblasts; Fibrosis; Glycolysis; Kidney Diseases; Kidney Tubules; Macrophages; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; Signal Transduction; Ureteral Obstruction

Shikonin, isolated from the roots of herbal plant Lithospermum erythrorhizon, is a naphthoquinone. It has been reported to exert beneficial anti-inflammatory effects and anti-oxidant properties in various diseases. Isoproterenol (ISO) has been widely used to establish cardiac injury in vivo and in vitro. However, shikonin function in ISO-induced cardiac injury remains uncertain. In our study, we attempted to investigate the efficiency and possible molecular mechanism of shikonin in cardiac injury treatment induced by ISO. In vivo, C57BL6 mice were subcutaneously injected with 5mg/kg ISO to induce heart failure. And mice were given a gavage of shikonin (2 or 4mg/kg/d, for four weeks). Cardiac function, fibrosis indices, inflammation response, apoptosis and endoplasmic reticulum (ER) stress were calculated. Pathological alterations, fibrosis-, inflammation-, apoptosis- and ER stress-related molecules were examined. In ISO-induced cardiac injury, shikonin significantly ameliorated heart function, decreased myocardial fibrosis, suppressed inflammation, attenuated apoptosis and ER stress through impeding collagen accumulation, Toll like receptor 4/nuclear transcription factor κB (TLR4/NF-κB), Caspase-3 and glucose-regulated protein 78 (GRP78) signaling pathways activity, relieving heart failure in vivo. Also, in vitro, shikonin attenuated ISO-induced cardiac muscle cells by reducing fibrosis, inflammation, apoptosis and ER stress. Our findings indicated that shikonin treatment attenuated ISO-induced heart injury, providing an effective therapeutic strategy for heart failure treatment for future.

Topics: Animals; Apoptosis; Cardiomyopathies; Caspase 3; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Fibrosis; Gene Expression Regulation; Heart; Heart Failure; HSP70 Heat-Shock Proteins; Inflammation; Isoproterenol; Male; Membrane Proteins; Mice; Mice, Inbred C57BL; Myocardium; Myocytes, Cardiac; Naphthoquinones; NF-kappa B

Chronic kidney diseases generally lead to renal fibrosis. Despite great progress having been made in identifying molecular mediators of fibrosis, the mechanism that governs renal fibrosis remains unclear, and so far no effective therapeutic antifibrosis strategy is available. Here we demonstrated that a switch of metabolism from oxidative phosphorylation to aerobic glycolysis (Warburg effect) in renal fibroblasts was the primary feature of fibroblast activation during renal fibrosis and that suppressing renal fibroblast aerobic glycolysis could significantly reduce renal fibrosis. Both gene and protein assay showed that the expression of glycolysis enzymes was upregulated in mouse kidneys with unilateral ureter obstruction (UUO) surgery or in transforming growth factor-β1 (TGF-β1)-treated renal interstitial fibroblasts. Aerobic glycolysis flux, indicated by glucose uptake and lactate production, was increased in mouse kidney with UUO nephropathy or TGF-β1-treated renal interstitial fibroblasts and positively correlated with fibrosis process. In line with this, we found that increasing aerobic glycolysis can remarkably induce myofibroblast activation while aerobic glycolysis inhibitors shikonin and 2-deoxyglucose attenuate UUO-induced mouse renal fibrosis and TGF-β1-stimulated myofibroblast activation. Furthermore, mechanistic study indicated that shikonin inhibits renal aerobic glycolysis via reducing phosphorylation of pyruvate kinase type M2, a rate-limiting glycolytic enzyme associated with cell reliance on aerobic glycolysis. In conclusion, our findings demonstrate the critical role of aerobic glycolysis in renal fibrosis and support treatment with aerobic glycolysis inhibitors as a potential antifibrotic strategy.

Topics: Animals; Carrier Proteins; Cell Line; Deoxyglucose; Disease Models, Animal; Fibrosis; Glycolysis; Kidney; Male; Membrane Proteins; Mice; Myofibroblasts; Naphthoquinones; Phosphorylation; Pyruvate Kinase; Rats; Renal Insufficiency, Chronic; Thyroid Hormone-Binding Proteins; Thyroid Hormones; Time Factors; Transforming Growth Factor beta1; Ureteral Obstruction

Therapeutic management of diabetic myocardial fibrosis remains an unsolved clinical problem. Pin1, a peptidyl-prolyl isomerase, impacts diverse cellular processes and plays a pivotal role in regulating cardiac pathophysiology. Here we investigate the potential mechanism of action of Pin1 and its role in diabetes-induced myocardial fibrosis and dysfunction in mice. Cardiac Pin1, transforming growth factor β1 (TGF-β1), α-smooth muscle actin (α-SMA) and extracellular matrix deposits (collagen I and III) are found to be increased in diabetic mice, which are effectively prevented by Pin1 inhibition by juglone. Pin1 inhibition alleviates cardiac fibrosis and dysfunction. In vitro, high glucose increases Pin1 expression with an accompanying increase in phospho-Akt (Ser 473), p-Smad2, p-Smad3, TGF-β1, and α-SMA in cardiac fibroblasts (CFs). These increases are effectively prevented by the inhibition of Pin1 by juglone. Furthermore, Pin1 inhibition inhibits HG-induced CF proliferation and migration. Our results indicate that Pin1 inhibition attenuates cardiac extracellular matrix deposition by regulating the phosphorylation of Akt, TGF-β1/Smads, MMP activities, and α-SMA expression in diabetic mice.

Topics: Actins; Animals; Animals, Newborn; Blotting, Western; Cell Movement; Cell Proliferation; Cells, Cultured; Collagen Type I; Collagen Type III; Diabetes Mellitus, Experimental; Enzyme Inhibitors; Fibroblasts; Fibrosis; Glucose; Male; Mice, Inbred C57BL; Microscopy, Confocal; Myocardium; Naphthoquinones; NIMA-Interacting Peptidylprolyl Isomerase; Phosphorylation; Proto-Oncogene Proteins c-akt; Reverse Transcriptase Polymerase Chain Reaction; Smad Proteins, Receptor-Regulated; Transforming Growth Factor beta1

Lipotoxic cardiomyopathy is caused by myocardial lipid accumulation and often occurs in patients with diabetes and obesity. This study investigated the effects of β-lapachone (β-lap), a natural compound that activates Sirt1 through elevation of the intracellular NAD+ level, on acyl CoA synthase (ACS) transgenic (Tg) mice, which have lipotoxic cardiomyopathy. Oral administration of β-lap to ACS Tg mice significantly attenuated heart failure and inhibited myocardial accumulation of triacylglycerol. Electron microscopy and measurement of mitochondrial complex II protein and mitochondrial DNA revealed that administration of β-lap restored mitochondrial integrity and biogenesis in ACS Tg hearts. Accordingly, β-lap administration significantly increased the expression of genes associated with mitochondrial biogenesis and fatty acid metabolism that were down-regulated in ACS Tg hearts. β-lap also restored the activities of Sirt1 and AMP-activated protein kinase (AMPK), the two key regulators of metabolism, which were suppressed in ACS Tg hearts. In H9C2 cells, β-lap-mediated elevation of AMPK activity was retarded when the level of Sirt1 was reduced by transfection of siRNA against Sirt1. Taken together, these results indicate that β-lap exerts cardioprotective effects against cardiac lipotoxicity through the activation of Sirt1 and AMPK. β-lap may be a novel therapeutic agent for the treatment of lipotoxic cardiomyopathy.

Topics: Acyl Coenzyme A; Acyltransferases; AMP-Activated Protein Kinases; Animals; Cardiomyopathies; Fibrosis; Gene Knockdown Techniques; Lipids; Mice, Transgenic; Mitochondria, Heart; Myocardium; Naphthoquinones; Signal Transduction; Sirtuin 1; Triglycerides; Ultrasonography; Ventricular Remodeling

NADPH oxidase (NOX) is a predominant source of reactive oxygen species (ROS), and the activity of NOX, which uses NADPH as a common rate-limiting substrate, is upregulated by prolonged dietary salt intake. β-Lapachone (βL), a well-known substrate of NAD(P)H:quinone oxidoreductase 1 (NQO1), decreases the cellular NAD(P)H/NAD(P)(+) ratio via activation of NQO1. In this study, we evaluated whether NQO1 activation by βL modulates salt-induced renal injury associated with NOX-derived ROS regulation in an animal model. Dahl salt-sensitive (DS) rats fed a high-salt (HS) diet were used to investigate the renoprotective effect of NQO1 activation. βL treatment significantly lowered the cellular NAD(P)H:NAD(P)(+) ratio and dramatically reduced NOX activity in the kidneys of HS diet-fed DS rats. In accordance with this, total ROS production and expression of oxidative adducts also decreased in the βL-treated group. Furthermore, HS diet-induced proteinuria and glomerular damage were markedly suppressed, and inflammation, fibrosis, and apoptotic cell death were significantly diminished by βL treatment. This study is the first to demonstrate that activation of NQO1 has a renoprotective effect that is mediated by NOX activity via modulation of the cellular NAD(P)H:NAD(P)(+) ratio. These results provide strong evidence that NQO1 might be a new therapeutic target for the prevention of salt-induced renal injury.

Topics: Acute Kidney Injury; Animals; Apoptosis; Enzyme Activation; Enzyme Activators; Fibrosis; Inflammation; Kidney Glomerulus; Male; NAD(P)H Dehydrogenase (Quinone); NADP; NADPH Oxidases; Naphthoquinones; Oxidation-Reduction; Oxidative Stress; Rats; Rats, Inbred Dahl; Reactive Oxygen Species; Sodium Chloride

Systemic sclerosis (SSc) is a connective tissue disorder characterized by skin and visceral fibrosis, microvascular damage, and autoimmunity. HOCl-induced mouse SSc is a murine model that mimics the main features of the human disease, especially the activation and hyperproliferation rate of skin fibroblasts. We demonstrate here the efficiency of a tellurium-based catalyst 2,3-bis(phenyltellanyl)naphthoquinone ((PHTE)(2)NQ) in the treatment of murine SSc, through its selective cytotoxic effects on activated SSc skin fibroblasts. SSc mice treated with (PHTE)(2)NQ displayed a significant decrease in lung and skin fibrosis and in alpha-smooth muscle actin (α-SMA) expression in the skin compared with untreated mouse SSc animals. Serum concentrations of advanced oxidation protein products, nitrate, and anti-DNA topoisomerase I autoantibodies were increased in SSc mice, but were significantly reduced in SSc mice treated with (PHTE)(2)NQ. To assess the mechanism of action of (PHTE)(2)NQ, the cytotoxic effect of (PHTE)(2)NQ was compared in normal fibroblasts and in mouse SSc skin fibroblasts. ROS production is higher in mouse SSc fibroblasts than in normal fibroblasts, and was still increased by (PHTE)(2)NQ to reach a lethal threshold and kill mouse SSc fibroblasts. Therefore, the effectiveness of (PHTE)(2)NQ in the treatment of mouse SSc seems to be linked to the selective pro-oxidative and cytotoxic effects of (PHTE)(2)NQ on hyperproliferative fibroblasts.

Topics: Actins; Animals; Autoantibodies; Cells, Cultured; Disease Models, Animal; DNA Topoisomerases, Type I; Female; Fibroblasts; Fibrosis; Glutathione; Hydrogen Peroxide; Hypochlorous Acid; In Vitro Techniques; Mice; Mice, Inbred BALB C; Naphthoquinones; Nitric Oxide; Organometallic Compounds; Reactive Oxygen Species; Scleroderma, Systemic; Skin; Tellurium