Metabolomic profiling analysis reveals the benefits of ginseng berry intake on mitochondrial function and glucose metabolism in the liver of obese mice.

INTRODUCTION: Ginseng berry (GB) has previously been demonstrated to improve systemic insulin resistance and regulate hepatic glucose metabolism and steatosis in mice with diet-induced obesity (DIO). OBJECTIVES: In this study, the role of GB in metabolism was assessed using metabolomics analysis on the total liver metabolites of DIO mice. METHODS: Metabolomic profiling was performed using capillary electrophoresis time-of-flight mass spectrometry (CE-TOF/MS) of liver tissue from mice on a 12-wk normal chow diet (NC), high-fat diet (HFD), and HFD supplemented with 0.1% GB (HFD + GB). The detected metabolites, its pathways, and functions were analyzed through partial least square discriminant analysis (PLS-DA), the small molecular pathway database (SMPDB), and MetaboAnalyst 5.0. RESULTS: The liver metabolite profiles of NC, HFD, and GB-fed mice (HFD + GB) were highly compartmentalized. Metabolites involved in major liver functions, such as mitochondrial function, gluconeogenesis/glycolysis, fatty acid metabolism, and primary bile acid biosynthesis, showed differences after GB intake. The metabolites that showed significant correlations with fasting blood glucose (FBG), insulin, and homeostatic model assessment for insulin resistance (HOMA-IR) were highly associated with mitochondrial membrane function, energy homeostasis, and glucose metabolism. Ginseng berry intake increased the levels of metabolites involved in mitochondrial membrane function, decreased the levels of metabolites related to glucose metabolism, and was highly correlated with metabolic phenotypes. CONCLUSION: This study demonstrated that long-term intake of GB changed the metabolite of hepatosteatotic livers in DIO mice, normalizing global liver metabolites involved in mitochondrial function and glucose metabolism and indicating the potential mechanism of GB in ameliorating hyperglycemia in DIO mice.

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.

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.

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.

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.

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.

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.

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.

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.

Granulocyte colony-stimulating factor induces in vitro lymphangiogenesis.

Granulocyte-colony stimulating factor (G-CSF) is reported to induce differentiation in cells of the monocyte lineage and angiogenesis in vascular endothelial cells, but its effects on lymphangiogenesis is uncertain. Here we examined the effects and the mechanisms of G-CSF-induced lymphangiogenesis using human lymphatic endothelial cells (hLECs). Our results showed that G-CSF induced capillary-like tube formation, migration and proliferation of hLECs in a dose- and time-dependent manner and enhanced sprouting of thoracic duct. G-CSF increased phosphorylation of Akt and ERK1/2 in hLECs. Supporting the observations, specific inhibitors of phosphatidylinositol 3'-kinase and MAPK suppressed the G-CSF-induced in vitro lymphangiogenesis and sprouting. Intraperitoneal administration of G-CSF to mice also stimulated peritoneal lymphangiogenesis. These findings suggest that G-CSF is a lymphangiogenic factor.

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.

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.

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.

The effects of designed angiopoietin-1 variant on lipid droplet diameter, vascular endothelial cell density and metabolic parameters in diabetic db/db mice.

Metabolic syndrome consists of metabolic abnormality with central obesity, hypertriglyceridemia, insulin resistance and hypertension. Adipose tissue has been known as a primary site of insulin resistance and its adipocyte size may be correlated with the degree of insulin resistance. A designed angiopoietin-1, COMP-Angiopoietin-1 (COMP-Ang1), mitigated high-fat diet-induced insulin resistance in skeletal muscle. In this study, we examined effects of COMP-Ang1 on adipocyte droplet size, vascular endothelial cell density in adipose tissue and metabolic parameters in db/db mice by administering COMP-Ang1 or LacZ (as a control) adenovirus. Administration of COMP-Ang1 decreased fat droplet diameter in epididymal and abdominal visceral adipocyte and visceral fat content in db/db mice. The density of vascular endothelial cell in adipose tissue was increased in db/db mice after treatment with COMP-Ang1. Serum resistin and tumor necrosis factor-α level was lower after treatment with COMP-Ang1 in db/db mice. COMP-Ang1 caused a restoration of fasting glycemic control in db/db mice and decreased serum insulin level and insulin resistance measured by HOMA index. These findings indicate that COMP-Ang1 regulates adipocyte fat droplet diameter, vascular endothelial cell density and metabolic parameters in db/db mice.

SIRT1 overexpression decreases cisplatin-induced acetylation of NF-κB p65 subunit and cytotoxicity in renal proximal tubule cells.

As the increased acetylation of p65 is linked to nuclear factor-κB (NF-κB) activation, the regulation of p65 acetylation can be a potential target for the treatment of inflammatory injury. Cisplatin-induced nephrotoxicity is an important issue in chemotherapy of cancer patients. SIRT1, nicotinamide adenine dinucleotide (NAD(+))-dependent protein deacetylase, has been implicated in a variety of cellular processes such as inflammatory injury and the control of multidrug resistance in cancer. However, there is no report on the effect of SIRT1 overexpression on cisplatin-induced acetylation of p65 subunit of NF-κB and cell injury. To investigate the effect of SIRT1 in on cisplatin-induced acetylation of p65 subunit of NF-κB and cell injury, HK2 cells were exposed with SIRT1 overexpression, LacZ adenovirus or dominant negative adenovirus after treatment with cisplatin. While protein expression of SIRT1 was decreased by cisplatin treatment compared with control buffer treatment, acetylation of NF-κB p65 subunit was significantly increased after treatment with cisplatin. Overexpression of SIRT1 ameliorated the increased acetylation of p65 of NF-κB during cisplatin treatment and cisplatin-induced cytotoxicity. Further, treatment of cisplatin-treated HK2 cells with resveratrol, a SIRT1 activator, also decreased acetylation of NF-κB p65 subunit and cisplatin-induced increase of the cell viability in HK2 cells. Our findings suggests that the regulation of acetylation of p65 of NF-κB through SIRT1 can be a possible target to attenuate cisplatin-induced renal cell damage.

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.

SIRT1 activation by resveratrol ameliorates cisplatin-induced renal injury through deacetylation of p53.

Nephrotoxicity is one of the important dose-limiting factors during cisplatin treatment. There is a growing body of evidence that activation of p53 has a critical role in cisplatin-induced renal apoptotic injury. The nicotinamide adenine dinucleotide-dependent protein deacetylase SIRT1 decreases apoptosis through deacetylating of p53, and resveratrol is known as an activator of SIRT1. To study the role of SIRT1 in cisplatin-induced renal injury through interaction with p53, mouse proximal tubular cells (MPT) were treated with cisplatin and examined the expression level of SIRT1, acetylation of p53, PUMA-α, Bax, the cytosolic/mitochondrial cytochrome c ratio, and active caspase-3. The expression of SIRT1 was decreased by cisplatin. Resveratrol, a SIRT1 activator, ameliorated cisplatin-induced acetylation of p53, apoptosis, and cytotoxicity in MPT cells. In addition, resveratrol remarkably blocked cisplatin-induced decrease of Bcl-xL in MPT cells. Further specific SIRT1 inhibition with EX 527 or small interference RNA specific to SIRT1 reversed the effect of resveratrol on cisplatin-induced toxicity. Inhibition of p53 by pifithrin-α reversed the effect of EX527 in protein expression of PUMA-α, Bcl-xL, and caspase-3 and cytotoxicity in MPT cells. SIRT1 protein expression after cisplatin treatment was significantly decreased in the kidney. SIRT1 activation by resveratrol decreased cisplatin-induced apoptosis while improving the glomerular filtration rate. Taken together, our findings suggest that the modulation of p53 by SIRT1 could be a possible target to attenuate cisplatin-induced kidney injury.

Luteolin ameliorates cisplatin-induced acute kidney injury in mice by regulation of p53-dependent renal tubular apoptosis.

BACKGROUND: Cisplatin chemotherapy often causes acute kidney injury in cancer patients. The causative mechanisms of cisplatin-induced acute kidney injury include renal inflammation, activation of p53 tumour suppressor protein and tubular apoptosis. Luteolin, a flavone found in medicinal herbs and plants, has been reported to exhibit anti-inflammatory, antioxidant and anticarcinogenic activities. The purpose of this study was to investigate the anti-apoptotic effect of luteolin on cisplatin-induced acute kidney injury and the molecular mechanism. METHODS: C57BL/6 mice were treated with cisplatin (20 mg/kg) with or without treatment with luteolin (50 mg/kg for 3 days). Renal function, histological changes, degree of oxidative stress and tubular apoptosis were examined. The effects of luteolin on cisplatin-induced expression of renal p53, PUMA-α and Bcl-2 family proteins were evaluated. RESULTS: Treatment of mice with cisplatin resulted in renal damage, showing an increase in blood urea nitrogen and creatinine levels, tubular damage, oxidative stress and apoptosis. Treatment of cisplatin-treated mice with luteolin significantly improved renal dysfunction, reducing tubular cell damage, oxidative stress and apoptosis. Examination of molecules involving apoptosis of the kidney revealed that treatment of cisplatin increased the levels of p53 and its phosphorylation, PUMA-α, Bax and caspase-3 activity that were significantly decreased by treatment with luteolin. CONCLUSION: These results indicate that cisplatin induces acute kidney injury by regulation of p53-dependent renal tubular apoptosis and that luteolin ameliorates the cisplatin-mediated nephrotoxicity through down-regulation of p53-dependent apoptotic pathway in the kidney.

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.