Chrysanthemum coronarium L. Extract Attenuates Homocysteine-Induced Vascular Inflammation in Vascular Smooth Muscle Cells.

Hyperhomocysteinemia is a main risk factor for phenotypic modulation of vascular smooth muscle cells (VSMCs) and atherosclerosis. Phenotypic switching and proliferation of VSMCs are related to the progression of vascular inflammation. Chrysanthemum coronarium L. is a leafy vegetable with various biological functions, such as antioxidative, anti-inflammatory, and antiproliferative effects. In this study, we aimed to identify the mechanisms underlying the therapeutic and preventive effects of C. coronarium L. extract (CC) in regulating homocysteine (Hcy)-induced vascular inflammation in human aortic VSMCs. CC did not exhibit cytotoxicity and inhibited Hcy-stimulated VSMC proliferation and migration. In addition, CC promoted Hcy-induced expression of VSMC contractile phenotype proteins, including alpha-smooth muscle actin, calponin, and smooth muscle 22α. CC also decreased Hcy-induced accumulation of reactive oxygen species and expression of inflammatory markers nicotinamide adenine dinucleotide phosphate oxidase-4 and soluble epoxide hydrolase. These results showed that CC attenuates Hcy-induced inflammatory responses, highlighting its potential as a therapeutic or preventive target for Hcy-induced vascular inflammation.

Renoprotective Effect of Chrysanthemum coronarium L. Extract on Adenine-Induced Chronic Kidney Disease in Mice.

Chronic kidney disease (CKD) gradually leads to loss of renal function and is associated with inflammation and fibrosis. Chrysanthemum coronarium L., a leafy vegetable, possesses various beneficial properties, including anti-oxidative, anti-inflammatory, and antiproliferative effects. In this study, we investigated the renoprotective effect of Chrysanthemum coronarium L. extract (CC) on adenine (AD)-induced CKD in mice. CKD was induced by feeding mice with an AD diet (0.25% w/w) for 4 weeks. Changes in renal function, histopathology, inflammation, and renal interstitial fibrosis were analyzed. The adenine-fed mice were characterized by increased blood urea nitrogen, serum creatinine, and histological changes, including inflammation and fibrosis; however, these changes were significantly restored by treatment with CC. Additionally, CC inhibited the expression of the inflammatory markers, monocyte chemoattractant protein-1, interleukins-6 and -1ß, intercellular adhesion molecule-1, and cyclooxygenase 2. Moreover, CC suppressed the expression of the fibrotic markers, type IV collagen, and fibronectin. Furthermore, CC attenuated the expression of profibrotic genes (tumor growth factor-ß and α-smooth muscle actin) in AD-induced renal injury mice. Thus, our results suggest that CC has the potential to attenuate AD-induced renal injury and might offer a new option as a renoprotective agent or functional food supplement to manage CKD.

Effect of Menaquinone-4 on Receptor Activator of Nuclear Factor κB Ligand-Induced Osteoclast Differentiation and Ovariectomy-Induced Bone Loss.

Osteoporosis is a progressive metabolic disease characterized by decreased bone mineral density and increased fracture risk. Previous studies have shown that higher intake of vitamin K (VK) correlates with a reduced risk of osteoporosis. However, the effect of menaquinone-4 (MK-4), a specific form of VK, still remains obscure. Therefore, in this study, we investigated the effects of MK-4 on osteoclast differentiation by differentiating RAW 264.7 cells into osteoclasts with the help of receptor activator of nuclear factor-kappa B ligand (RANKL), assessed the mRNA expression of osteoclast-specific genes, and studied the effects of MK-4 in vivo in ovariectomized mice, a postmenopausal osteoporosis murine model. MK-4 inhibited osteoclast differentiation, decreased the mRNA expression of nuclear factor of activated T cells c1 (NFATc1), osteoclast-associated receptor (OSCAR), and cathepsin K (CTSK), and inhibited bone loss in ovariectomized mice. The findings strongly suggest that MK-4 is a therapeutic alternative for postmenopausal osteoporosis.

Chrysanthemum coronarium L. Protects against Premature Senescence in Human Endothelial Cells.

The senescence of vascular endothelial cells (EC) leads to vascular dysfunction. However, the molecular mechanisms of EC senescence and its associated pathophysiological changes have not yet been clearly studied. This study sought to inspect the Chrysanthemum coronarium L. (CC) extract's mechanism in preventing premature senescence of EC. A senescent endothelial cell model was created in human umbilical vein endothelial cells (HUVECs) with 100 µmol/L H2O2 treatment for 24 h. The effect of CC on senescent HUVECs was elucidated by measuring the activity of ß-galactosidase (SA-ß-gal), which exhibits an aging-related phenotype. SA-ß-gal activity increased to 13.2 ± 2.85% in H2O2-treated HUVECs, whereas this activity was attenuated in the CC group. Immunoblot analyses revealed that p21, p53, and PAI-1 levels increased in the senescent HUVECs; however, the levels decreased in the HUVECs treated with various concentrations of CC (10, 20, and 50 µg/mL). The CC extract reduced the production of reactive oxygen species and reversed the decrease in NO production. Additionally, pretreatment with an Nω-nitro-l-arginine methyl ester (eNOS inhibitor) and nicotinamide (sirtuin 1 inhibitor) inhibited the anti-senescent effect of CC extract in HUVECs. Taken together, this study validated the novel endothelial protective effect of CC extract and its prevention of senescence in HUVECs through the mechanism regulated by eNOS and SIRT1 expression.

Soluble epoxide hydrolase inhibitor, TPPU, attenuates progression of atherosclerotic lesions and vascular smooth muscle cell phenotypic switching.

Atherosclerosis manifests as a chronic inflammation resulting from multiple interactions between circulating factors and various cell types in blood vessel walls. Growing evidence shows that phenotypic switching and proliferation of vascular smooth muscle cells (VSMCs) plays an important role in the progression of atherosclerosis. Soluble epoxide hydrolase (sEH)/epoxyeicosatrienoic acids are mediated by vascular inflammation. N-[1-(1-oxopropyl)-4-piperidinyl]-N'-[4-(trifluoromethoxy)phenyl]-urea (TPPU) is an sEH inhibitor. This study investigated the therapeutic effect of TPPU on atherosclerosis in vivo and homocysteine-induced vascular inflammation in vitro and explored their molecular mechanisms. We found that TPPU decreased WD-induced atherosclerotic plaque lesions, inflammation, expression of sEH, and nicotinamide adenine dinucleotide phosphate oxidase-4 (Nox4), and increased the expression of contractile phenotype marker of aortas in ApoE (-/-) mice. TPPU also inhibited homocysteine-stimulated VSMC proliferation, migration, and phenotypic switching, and reduced Nox4 in human-aorta-VSMC regulation. We conclude that TPPU has anti-atherosclerotic effects, potentially because of the suppression of VSMC phenotype switching. Thus, TPPU could be a potential therapeutic target for phenotypic switching attenuation in atherosclerosis.

Preventive Effects of Chrysanthemum coronarium L. Extract on Bone Metabolism In Vitro and In Vivo.

Osteoporosis is characterized by decreased bone mass and bone microarchitectural failure, leading to an enhanced risk of bone fractures. Chrysanthemum coronarium L. (CC) is a natural plant with powerful antioxidant activity. This study investigated the antiosteoporotic effects of CC extracts in in vitro cell cultures and in vivo bone loss animal models. CC stimulated osteoblast differentiation and mineralized bone formation by osteoblasts by increasing the expression of bone formation markers (alkaline phosphatase, osteoprotegerin, and osteoprotegerin/receptor activator nuclear factor-κB ligand ratio) in the murine preosteoblastic cell line MC3T3-E1. Additionally, CC was found to inhibit osteoclast differentiation by downregulating bone resorption markers (tartrate-resistant acid phosphatase, cathepsin K, dendritic cell-specific transmembrane protein, and calcitonin receptor) in the murine macrophage-like cell line RAW264.7. CC prevented ovariectomy-induced bone loss, preserved trabecular microarchitecture, and improved serum bone turnover markers in an osteoporotic mouse model. These findings suggest that CC extract may be considered as a natural therapeutic or preventive agent for osteoporotic bone loss.

The Effect of Artemisinin on Inflammation-Associated Lymphangiogenesis in Experimental Acute Colitis.

Inflammatory bowel disease (IBD) is characterized by inflammation, angiogenesis, and lymphangiogenesis. Artemisinin (Art), a chemical compound isolated from Artemisia annua L. (sweet wormwood), has several biochemical properties including antibacterial, anticancer, anti-inflammation, and anti-angiogenesis effects. We investigated the effects of Art on inflammation-induced lymphangiogenesis in a dextran sulfate sodium (DSS)-induced mouse acute colitis model. The mice were orally administered Art for 7 days before being evaluated using the disease activity index (DAI) and documenting colonic inflammatory changes, colon edema, microvessel density, lymphatic vessel density (LVD), proinflammatory cytokine levels, and vascular endothelial growth factor (VEGF)-C and VEGF-D/VEGF receptor (VEGFR)-3 mRNA expression levels in colon tissue. Art reduced DSS-induced lymphatic vessel endothelial hyaluronan receptor-1-positive LVD. Art also reduced the symptoms of colitis, improved tissue histology, and relieved inflammatory edema in mice affected by colitis. In addition, Art decreased the infiltration of immunomodulatory cells and inflammatory cytokines, which involved reduction of VEGF-C, -D, and VEGFR-3 expression. Taken together, our findings suggest that Art ameliorates inflammation-driven lymphangiogenesis in an experimental colitis mouse model via the VEGF-C/VEGFR-3 signaling pathway, implicating this pathway as a potential target for the treatment of IBD.

Amaranthus mangostanus Inhibits the Differentiation of Osteoclasts and Prevents Ovariectomy-Induced Bone Loss.

Bone homeostasis is dynamically balanced between bone forming osteoblasts and bone resorbing osteoclasts. Osteoclasts play an important role in bone destruction and osteoporosis, and they are derived from monocyte/macrophages in response to macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor κB (NF-κB) ligand (RANKL). Amaranthus mangostanus L. (AM) is a plant with powerful antioxidant and other biological activities including anti-inflammatory, antidiabetic, and antihyperlipidemic effects. However, its effects on bone health are unknown. In this study, we explored whether AM could affect RANK-mediated osteoclastogenesis. AM significantly suppressed RANKL-induced osteoclast differentiation and expression of osteoclast-specific genes, TRAP, cathepsin K, NF-activated T-cells (NFATc1), and Dc-stamp in RAW 264.7 cells. Moreover, AM significantly inhibited extracellular signal-regulated kinase (ERK), Akt, and NF-κB signaling pathways in RAW 264.7 cells. In addition, AM preserved ovariectomy-induced bone loss in mice. Taken together, our results suggest that AM might be a potential candidate for the treatment of postmenopausal osteoporosis.

Peanut shell extract inhibits the development of dextran sulfate sodium (DSS)-induced colitis.

Inflammatory bowel diseases (IBD) induce inflammation in the colon and small intestine. IBD include ulcerative colitis and Crohn's disease, with such common symptoms as severe diarrhea, fever, and blood in the stool. In the current study, we explored the ability of peanut shell extract (PSE) to alleviate IBD in an experimental colonic inflammation model. Colitis was induced by orally administered dextran sulfate sodium (DSS) in mice. Peanut shell extract was prepared using a method of aqueous ethanol. DSS treatment reduced the colon length and mouse body weight, and aggravated disease condition compared with untreated control mice. Oral administration of 400 mg/kg PSE alleviated colon shortening, body weight loss, DAI, and colon injury score in DSS-induced colitis. These physiological improvements were validated by reduced levels of proinflammatory cytokines and infiltrating macrophage accumulation in the inflamed colon in the PSE administered group. These observations suggest that PSE may be developed as an alternative natural extract for the prevention or treatment of IBD.

COMP-angiopoietin-1 ameliorates inflammation-induced lymphangiogenesis in dextran sulfate sodium (DSS)-induced colitis model.

Alterations in the intestinal lymphatic network are pathological processes as related to inflammatory bowel disease (IBD). In this study, we demonstrated that reduction in inflammation-induced lymphangiogenesis ameliorates experimental acute colitis. A soluble and stable angiopoietin-1 (Ang1) variant, COMP-Ang1, possesses anti-inflammatory and angiogenic effects. We investigated the effects of COMP-Ang1 on an experimental colonic inflammation model. Experimental colitis was induced in mice by administering 3% dextran sulfate sodium (DSS) via drinking water. We determined body weight, disease activity indices, histopathological scores, lymphatic density, anti-ER-HR3 staining, and the expression of members of the vascular endothelial growth factor (VEGF) family and various inflammatory cytokines in the mice. The density of lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) and VEGFR-3-positive lymphatic vessels increased in mice with DSS-induced colitis. We observed that COMP-Ang1-treated mice showed less weight loss, fewer clinical signs of colitis, and longer colons than Ade-DSS-treated mice. COMP-Ang1 also significantly reduced the density of LYVE-1-positive lymphatic vessels and the disruption of colonic architecture that is normally associated with colitis and repressed the immunoregulatory response. Further, COMP-Ang1 treatment reduced both M1 and M2 macrophage infiltration into the inflamed colon, which involved inhibition of VEGF-C and D expression. Thus, COMP-Ang1, which acts by reducing inflammation-induced lymphangiogenesis, may be used as a novel therapeutic for the treatment of IBD and other inflammatory diseases. KEY MESSAGES: COMP-Ang1 decreases inflammatory-induced lymphangiogenesis in experimental acute colitis. COMP-Ang1 improves the symptom of DSS-induced inflammatory response. COMP-Ang1 reduces the expression of pro-inflammatory cytokines in inflamed colon. COMP-Ang1 reduces the expression of VEGFs in inflamed colon. COMP-Ang1 prevents infiltration of macrophages in a DSS-induced colitis model.

Honokiol Improves Liver Steatosis in Ovariectomized Mice.

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease, and is associated with the development of metabolic syndrome. Postmenopausal women with estrogen deficiency are at a higher risk of progression to NAFLD. Estrogen has a protective effect against the progression of the disease. Currently, there are no safe and effective treatments for these liver diseases in postmenopausal women. Honokiol (Ho), a bioactive natural product derived from Magnolia spp, has anti-inflammatory, anti-angiogenic, and anti-oxidative properties. In our study, we investigated the beneficial effects of Ho on NAFLD in ovariectomized (OVX) mice. We divided the mice into four groups, as follows: SHAM, OVX, OVX+ß-estradiol (0.4 mg/kg of bodyweight), and OVX+Ho (50 mg/kg of diet). Mice were fed diets with/without Ho for 12 weeks. The bodyweight, epidermal fat, and weights of liver tissue were lower in the OVX group than in the other groups. Ho improved hepatic steatosis and reduced proinflammatory cytokine levels. Moreover, Ho markedly downregulated plasma lipid levels. Our results indicate that Ho ameliorated OVX-induced fatty liver and inflammation, as well as associated lipid metabolism. These findings suggest that Ho may be hepatoprotective against NAFLD in postmenopausal women.

Melandrii Herba Extract Attenuates H2O2-Induced Neurotoxicity in Human Neuroblastoma SH-SY5Y Cells and Scopolamine-Induced Memory Impairment in Mice.

Oxidative stress plays a significant role in the etiology of a variety of neurodegenerative diseases. In this study, we found that Melandrii Herba extract (ME) attenuated oxidative-induced damage in cells. Mechanistically, ME exhibited protection from H2O2-induced neurotoxicity via caspase-3 inactivation, Bcl-2 downregulation, Bax upregulation, and MAPK activation (ERK 1/2, JNK 1/2, and p38 MAPK) in vitro. Moreover, our in vivo data showed that ME was able to attenuate scopolamine-induced cognitive impairment. These results provide in vitro and in vivo evidence that ME exhibits neuroprotective properties against oxidative stress, which suggests that ME is worthy of further investigation as a complementary, or even as an alternative, product for preventing and treating neurodegenerative disorders.

Protective Effect of Allium tuberosum Extract on Vascular Inflammation in Tumor Necrosis Factor-α-induced Human Vascular Endothelial Cells.

BACKGROUND: Endothelial adhesion molecule expression induced by pro-inflammatory cytokine plays an important role in vascular endothelial cell injury, leading to vascular disease. Allium tuberosum (AT), which is used as a functional food, has a thrombolytic effect. It contains vitamin A, vitamin C, carbohydrate, calcium, iron, and phosphorus. There are many carotenes that turn into vitamin A in the body. Also, it helps blood circulation and stimulates metabolism. The purpose of the this study was to estimate the anti-inflammatory effects of the AT extract. METHODS: Human vascular endothelial cells were pre-treated with 100 µg/mL AT extract for 30 minutes and subsequently co-treated with TNF-α (10 ng/mL) and AT extract (100 µg/mL) for 1, 4, and 6 hours. After treatment, the cells were lysed and used for quantitative reverse transcription PCR, Western blot analysis, and monocyte adhesion assay. RESULTS: We examined the effect of the AT extract on inflammatory gene expression in TNF-α-induced human umbilical vein endothelial cells (HUVECs). The extract reduced the expression levels of mRNA and protein of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 in TNF-α-stimulated HUVECs. It also inhibited the TNF-α-induced phosphorylation of the NF-κB p65 subunit and degradation of IκBα. Furthermore, the AT extract prevented the increased adhesion capacity of monocyte to TNF-α-stimulated vascular endothelial cells by reducing ICAM-1 and VCAM-1 expression. CONCLUSIONS: The AT extract has preventive and anti-inflammatory effect against vascular disease and has potential for supporting prevention against the early process of atherosclerosis.

Effect of Oral Administration of 3,3'-Diindolylmethane on Dextran Sodium Sulfate-Induced Acute Colitis in Mice.

In patients with inflammatory bowel disease (IBD), inflammation is induced and maintained by lymphangiogenesis and angiogenesis. 3,3'-Diindolylmethane (DIM) is a natural product formed in acidic conditions from indole-3-carbinol in cruciferous vegetables, and it is known for its chemotherapeutic activity. This study evaluated DIM's effects on angiogenesis, lymphangiogenesis, and inflammation in a mouse colitis model. Experimental colitis was induced in mice by administering 3% dextran sulfate sodium (DSS) via drinking water. DIM remarkably attenuated the clinical signs and histological characteristics in mice with DSS-induced colitis. DIM suppressed neutrophil infiltration and pro-inflammatory cytokines. Moreover, it significantly suppressed the expression of vascular endothelial growth factor (VEGF)-A and VEGF receptor (VEGFR)-2, indicating that the mechanism may be related to the repression of pro-angiogenesis activity. DIM also remarkably suppressed the expression of VEGF-C, VEGF-D, VEGFR-3, and angiopoietin-2; thus, the mechanism may also be related to the suppression of lymphangiogenesis. Therefore, DIM is a possible treatment option for inflammation of the intestine and associated angiogenesis and lymphangiogenesis.

Paricalcitol attenuates lipopolysaccharide-induced myocardial inflammation by regulating the NF-κB signaling pathway.

Vitamin D deficiency is associated with an increased risk of cardiovascular disease, diabetes, colon and breast cancer, infectious diseases and allergies. Vascular alterations are an important pathophysiological mechanism of sepsis. Experimental data suggest that paricalcitol, a vitamin D2 analogue, exerts beneficial effects on renal inflammation and fibrosis. In the present study, we aimed to investigate the effects of paricalcitol on lipopolysaccharide (LPS)-induced myocardial inflammation and to elucidate the underlying mechanisms. We used primary cultured human umbilical vein endothelial cells for in vitro experiments, in which stimulation with tumor necrosis factor (TNF)-α was used to induce endothelial cell inflammation. For in vivo experiments, myocardial inflammation was induced by an intraperitoneal injection of 15 mg/kg LPS into C57BL6 mice pre-treated with or without 0.2 µg/kg paricalcitol. Treatment with paricalcitol suppressed the TNF-α-induced increase in the protein expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and fractalkine in endothelial cells. Treatment with paricalcitol also decreased the TNF-α-induced nuclear factor (NF)-κB binding activity. In a mouse model of LPS-induced myocardial inflammation, pre-treatment with paricalcitol prevented the LPS-induced increase in the expression of myocardial ICAM-1, phosphorylated p65 and myocardial TNF-α. Pre-treatment with paricalcitol also alleviated endotoxemia­induced microvascular leakage in the myocardium. The findings of our study suggest that paricalcitol exerts a protective effect against LPS-induced myocardial inflammation by regulating the expression of cell adhesion molecules and TNF-α, and by improving myocardial permeability.

Hyaluronan-induced VEGF-C promotes fibrosis-induced lymphangiogenesis via Toll-like receptor 4-dependent signal pathway.

Hyaluronan (HA), a component of the extracellular matrix, modulates cellular behavior including angiogenesis. However, little is known about the effect of HA on lymphangiogenesis in fibrosis model. In this study, we investigated the roles of HA in lymphangiogenesis of unilateral ureteral obstruction (UUO). We found that HA cooperated synergistically with vascular endothelial cell growth factor-C to stimulate capillary-like tube formation and increase migration of cells in a haptotaxis assay. Accumulation of HA in the cortical interstitial space was positively correlated with the number of lymphatic vessels after UUO. Depletion of macrophages with clodronate decreased UUO-induced HA accumulation and lymphangiogenesis. Additionally, hyaluronan synthase (HAS) mRNA expression and HA production were increased in bone marrow-derived macrophages upon stimulation with TGF-ß1. Transfer of mHAS2 and mHAS3 knock-down CD11b-positive macrophages to SCID mice resulted in a partial decrease in UUO-induced lymphangiogenesis. HA increased expression of vascular endothelial cell growth factor-C in macrophages. Vascular endothelial cell growth factor-C expression and LYVE-1-positive lymphatic area was significantly lower in the UUO-kidney from TLR4 null mice than that from TLR4 wild-type mice. Collectively, these results suggest that HA increases lymphangiogenesis in renal fibrosis model and also stimulates vascular endothelial cell growth factor-C production from macrophages through Toll-like receptor 4-dependent signal pathway.

Expression of human olfactory receptor 10J5 in heart aorta, coronary artery, and endothelial cells and its functional role in angiogenesis.

ORs are ectopically expressed in non-chemosensory tissues including muscle, kidney, and keratinocytes; however, their physiological roles are largely unknown. We found that human olfactory receptor 10J5 (OR10J5) is expressed in the human aorta, coronary artery, and umbilical vein endothelial cells (HUVEC). Lyral induces Ca(2+) and phosphorylation of AKT in HUVEC. A knockdown study showed the inhibition of the lyral-induced Ca(2+) and the phosphorylation AKT and implied that these processes are mediated by OR10J5. In addition, lyral enhanced migration of HUVEC, which were also inhibited by RNAi in a migration assay. In addition, matrigel plug assay showed that lyral enhanced angiogenesis in vivo. Together these data demonstrate the physiological role of OR10J5 in angiogenesis and represent roles of ORs in HUVEC cells.

SIRT2 Regulates LPS-Induced Renal Tubular CXCL2 and CCL2 Expression.

Sirtuin 2 (SIRT2), a NAD(+)-dependent histone deacetylase, is involved in carcinogenesis and genomic instability and modulates proinflammatory immune responses. However, its role in renal inflammatory injury has not been demonstrated. In this study, we explored the expression patterns of CXCL2 and CCL2 in kidney tissue from Sirt2(-/-) and Sirt2(+/+) mice and in mouse proximal tubular epithelial (MPT) cells. CXCL2 and CCL2 were significantly downregulated at both the mRNA and the protein levels in kidneys of LPS-treated Sirt2(-/-) mice compared with those of LPS-treated Sirt2(+/+) mice. Furthermore, SIRT2 deficiency ameliorated LPS-induced infiltration of neutrophils and macrophages, acute tubular injury, and decrease of renal function. Supporting these observations, CXCL2 and CCL2 expression levels were lower in MPT cells treated with SIRT2-siRNA than in cells treated with control-siRNA, and adenovirus-mediated overexpression of SIRT2 in MPT cells significantly increased the LPS-induced expression of CXCL2 and CCL2 at the mRNA and protein levels. In addition, SIRT2 interacted with mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1), and SIRT2-knockdown increased the acetylation of MKP-1 and suppressed the phosphorylation of p38 MAPK and c-Jun N-terminal kinase in LPS-treated MPT cells. SIRT2 also regulated p65 binding to the promoters of CXCL2 and CCL2. Taken together, these findings indicate that SIRT2 is associated with expression of renal CXCL2 and CCL2 and that regulation of SIRT2 might be an important therapeutic target for renal inflammatory injury.

Tamoxifen ameliorates renal tubulointerstitial fibrosis by modulation of estrogen receptor α-mediated transforming growth factor-ß1/Smad signaling pathway.

BACKGROUND: After insult to the kidney, a renal fibrotic process is initiated with sustained inflammation, fibroblast activation and accumulation of extracellular matrix (ECM). Tamoxifen has been used as an anti-estrogen for the prevention and treatment of breast cancer. In this study, we investigated the protective effects of tamoxifen on unilateral ureteral obstruction (UUO)-induced renal tubulointerstitial fibrosis and its molecular mechanism. METHODS: Renal fibrosis was induced by UUO in 7-week-old C57BL/6 mice. Tamoxifen (50 mg/kg) was given by oral gavage for 5 days before induction of renal fibrosis. Tamoxifen treatment was continued for 14 days after UUO operation. Histologic changes were examined by periodic acid-Schiff stain and Masson's trichrome stain. Expression of α-smooth muscle actin, vimentin, type I collagen, fibronectin and cell adhesion molecules were evaluated by immunohistochemistry and western blot analysis. We also evaluated the effect of tamoxifen on estrogen receptor (ER)-α-mediated transforming growth factor (TGF)-ß1/Smad signaling pathway in vitro. RESULTS: Renal tubular injury and fibrosis were increased after UUO. Tamoxifen treatment significantly decreased UUO-induced renal tubular injury and fibrosis. Renal fibroblast activation, ECM deposition and inflammation were significantly increased after ureteral ligation. However, tamoxifen treatment significantly decreased UUO-induced renal fibroblast activation, ECM deposition and inflammation by suppression of TGF-ß1/Smad signaling pathway in vivo. Tamoxifen decreased TGF-ß1-induced fibroblast proliferation and cell migration by modulating ERα-mediated TGF-ß1/Smad signaling pathway in vitro. CONCLUSION: These findings indicate that tamoxifen has a beneficial effect on UUO-induced tubulointerstitial fibrosis by suppression of renal fibroblast activation via modulation of ERα-mediated renal TGF-ß1/Smad signaling pathway.

SIRT2 ameliorates lipopolysaccharide-induced inflammation in macrophages.

INTRODUCTION: SIRT2 is a NAD(+)-dependent deacetylases and associated with numerous processes such as infection, carcinogenesis, DNA damage and cell cycle regulation. However, the role of SIRT2 in inflammatory process in macrophage remains unclear. MATERIALS AND METHODS: In the present study, we have evaluated the regulatory effects of SIRT2 in lipopolysaccharide (LPS)-stimulated macrophages isolated from SIRT2 knockout (KO) and wild type (WT) mice or Raw264.7 macrophage cells. As inflammatory parameters, expression of inducible nitric oxide synthase (iNOS), the productions of nitric oxide, reactive oxygen species (ROS) and M1-macrophage-related factors were evaluated. We also examined the effects of SIRT2 on activation of nuclear factor-kappaB (NFκB) signaling. RESULTS: SIRT2 deficiency inhibits LPS-induced iNOS mRNA and protein expression in bone marrow derived macrophages. SIRT2-siRNA transfection also suppressed LPS-induced iNOS expression in Raw264.7 macrophage cells. Bone marrow derived macrophages isolated from SIRT2 KO mice produced lower nitric oxide and expressed lower levels of M1-macrophage related markers including iNOS and CD86 in response to LPS than WT mice. Decrease of SIRT2 reduced the LPS-induced reactive oxygen species production. Deficiency of SIRT2 resulted in inhibition of NFκB activation through reducing the phosphorylation and degradation of IκBα. The phosphorylation and nuclear translocation of p65 was significantly decreased in SIRT2-deficient macrophages after LPS stimulation. DISCUSSION: Our data suggested that deficiency of SIRT2 ameliorates iNOS, NO expression and reactive oxygen species production with suppressing LPS-induced activation of NFκB in macrophages.