Association between dietary carotenoid intake and breast cancer risk: a case-control study among Korean women.

The association between dietary carotenoids and breast cancer (BC) risks were inconsistent. Therefore, this study investigated the association between dietary carotenoid and BC risks among Korean women. We recruited participants from the National Cancer Centre of Korea. Odds ratios and 95% confidence intervals were calculated with a logistic regression model. There was an inverse association between dietary carotenoid subclasses and BC risks; in particular, a higher intake of ß-carotene and lutein/zeaxanthin was associated with reduced BC risks. After subgroup analysis with estrogen receptor (ER)/progesterone receptor (PR) status, there was similar trend among ER-/PR- women. We further investigated which foods contribute to the carotenoid intake. A higher intake of radish leaves, kale, and bracken was associated with lowered BC risks. Accordingly, dietary carotenoid, particularly ß-carotene and lutein/zeaxanthin, appears to be associated with a lower risk of BC among Korean women.

Cirsium Setidens Water Extracts Containing Linarin Block Estrogen Deprivation-Induced Bone Loss in Mice.

Osteoporosis is evident in postmenopausal women and is an osteolytic disease characterized by bone loss that further increases the susceptibility to bone fractures and frailty. The use of complementary therapies to alleviate postmenopausal osteoporosis is fairly widespread among women. Edible Cirsium setidens contains various polyphenols of linarin, pectolinarin, and apigenin with antioxidant and hepatoprotective effects. This study aimed to determine whether Cirsium setidens water extracts (CSEs), the component linarin, and its aglycone acacetin blocked ovariectomy (OVX)-induced bone loss. This study employed OVX C57BL/6 female mice as a model for postmenopausal osteoporosis. CSEs, acacetin, or linarin was orally administrated to OVX mice at a dose of 20 mg/kg for 8 weeks. Surgical estrogen loss in mice for 8 weeks reduced bone mineral density (BMD) of mouse femur and serum 17ß-estradiol level and enhanced the serum receptor activator of NF-κB ligand/osteoprotegerin ratio with uterine atrophy. CSEs and linarin reversed such adverse effects and enhanced femoral BMD in OVX mice. Oral administration of CSEs and linarin attenuated tartrate-resistant acid phosphate activity and the induction of αvß3 integrins and proton suppliers in resorption lacunae in femoral bone tissue of OVX mice. In addition, CSEs and linarin curtailed the bone levels of cathepsin K and matrix metalloproteinase-9 responsible for osteoclastic bone resorption. On the other hand, CSEs and linarin enhanced the formation of trabecular bones in estrogen-deficient femur with increased induction of osteocalcin and osteopontin. Further, treatment with CSEs and linarin enhanced the collagen formation-responsive propeptide levels in the circulation along with the increase in the tissue non-specific alkaline phosphatase level in bone exposed to OVX. Supplementing CSEs, acacetin, or linarin to OVX mice elevated the formation of collagen fibers in OVX trabecular bone, evidenced using Picrosirius red staining. Accordingly, CSEs and linarin were effective in retarding osteoclastic bone resorption and promoting osteoblastic bone matrix mineralization under OVX conditions. Therefore, linarin, which is abundant in CSEs, may be a natural compound for targeting postmenopausal osteoporosis and pathological osteoresorptive disorders.

Aesculetin Accelerates Osteoblast Differentiation and Matrix-Vesicle-Mediated Mineralization.

The imbalance between bone resorption and bone formation in favor of resorption results in bone loss and deterioration of bone architecture. Osteoblast differentiation is a sequential event accompanying biogenesis of matrix vesicles and mineralization of collagen matrix with hydroxyapatite crystals. Considerable efforts have been made in developing naturally-occurring plant compounds, preventing bone pathologies, or enhancing bone regeneration. Coumarin aesculetin inhibits osteoporosis through hampering the ruffled border formation of mature osteoclasts. However, little is known regarding the effects of aesculetin on the impairment of matrix vesicle biogenesis. MC3T3-E1 cells were cultured in differentiation media with 1-10 µM aesculetin for up to 21 days. Aesculetin boosted the bone morphogenetic protein-2 expression, and alkaline phosphatase activation of differentiating MC3T3-E1 cells. The presence of aesculetin strengthened the expression of collagen type 1 and osteoprotegerin and transcription of Runt-related transcription factor 2 in differentiating osteoblasts for 9 days. When ≥1-5 µM aesculetin was added to differentiating cells for 15-18 days, the induction of non-collagenous proteins of bone sialoprotein II, osteopontin, osteocalcin, and osteonectin was markedly enhanced, facilitating the formation of hydroxyapatite crystals and mineralized collagen matrix. The induction of annexin V and PHOSPHO 1 was further augmented in ≥5 µM aesculetin-treated differentiating osteoblasts for 21 days. In addition, the levels of tissue-nonspecific alkaline phosphatase and collagen type 1 were further enhanced within the extracellular space and on matrix vesicles of mature osteoblasts treated with aesculetin, indicating matrix vesicle-mediated bone mineralization. Finally, aesculetin markedly accelerated the production of thrombospondin-1 and tenascin C in mature osteoblasts, leading to their adhesion to preformed collagen matrix. Therefore, aesculetin enhanced osteoblast differentiation, and matrix vesicle biogenesis and mineralization. These findings suggest that aesculetin may be a potential osteo-inductive agent preventing bone pathologies or enhancing bone regeneration.

Dietary Collagen Hydrolysates Ameliorate Furrowed and Parched Skin Caused by Photoaging in Hairless Mice.

Collagen hydrolysates have been suggested as a favorable antiaging modality in skin photoaged by persistent exposure to ultraviolet radiation (UV). The current study evaluated the beneficial effect of collagen hydrolysates (fsCH) extracted from Pangasius hypophthalmus fish skin on wrinkle formation and moisture preservation in dorsal skin of hairless mice challenged with UV-B. Inter-comparative experiments were conducted for anti-photoaging among fsCH, retinoic acid (RA), N-acetyl-D-glucosamine (NAG), and glycine-proline-hydroxyproline (GPH). Treating human HaCaT keratinocytes with 100-200 µg/mL fsCH reciprocally ameliorated the expression of aquaporin 3 (AQP3) and CD44 deranged by UV-B. The UV-B-induced deep furrows and skin thickening were improved in parched dorsal skin of mice supplemented with 206-412 mg/kg fsCH as well as RA and GPH. The UV-B irradiation enhanced collagen fiber loss in the dorsal dermis, which was attenuated by fsCH through enhancing procollagen conversion to collagen. The matrix metalloproteinase expression by UV-B in dorsal skin was diminished by fsCH, similar to RA and GPH, via blockade of collagen degradation. Supplementing fsCH to UV-B-irradiated mice decreased transepidermal water loss in dorsal skin with reduced AQP3 level and restored keratinocyte expression of filaggrin. The expression of hyaluronic acid synthase 2 and hyaluronidase 1 by UV-B was remarkably ameliorated with increased production of hyaluronic acid by treating fsCH to photoaged mice. Taken together, fsCH attenuated photoaging typical of deep wrinkles, epidermal thickening, and skin water loss, like NAG, RA, or GPH, through inhibiting collagen destruction and epidermal barrier impairment.

Astragalin Inhibits Cigarette Smoke-Induced Pulmonary Thrombosis and Alveolar Inflammation and Disrupts PAR Activation and Oxidative Stress-Responsive MAPK-Signaling.

Epidemiological evidence shows that smoking causes a thrombophilic milieu that may play a role in the pathophysiology of chronic obstructive pulmonary disease (COPD) as well as pulmonary thromboembolism. The increased nicotine level induces a prothrombotic status and abnormal blood coagulation in smokers. Since several anticoagulants increase bleeding risk, alternative therapies need to be identified to protect against thrombosis without affecting hemostasis. Astragalin is a flavonoid present in persimmon leaves and green tea seeds and exhibits diverse activities of antioxidant and anti-inflammation. The current study investigated that astragalin attenuated smoking-induced pulmonary thrombosis and alveolar inflammation. In addition, it was explored that molecular links between thrombosis and inflammation entailed protease-activated receptor (PAR) activation and oxidative stress-responsive mitogen-activated protein kinase (MAPK)-signaling. BALB/c mice were orally administrated with 10-20 mg/kg astragalin and exposed to cigarette smoke for 8 weeks. For the in vitro study, 10 U/mL thrombin was added to alveolar epithelial A549 cells in the presence of 1-20 µM astragalin. The cigarette smoking-induced the expression of PAR-1 and PAR-2 in lung tissues, which was attenuated by the administration of ≥10 mg/kg astragalin. The oral supplementation of ≥10 mg/kg astragalin to cigarette smoke-challenged mice attenuated the protein induction of urokinase plasminogen activator, plasminogen activator inhibitor-1and tissue factor, and instead enhanced the induction of tissue plasminogen activator in lung tissues. The astragalin treatment alleviated cigarette smoke-induced lung emphysema and pulmonary thrombosis. Astragalin caused lymphocytosis and neutrophilia in bronchoalveolar lavage fluid due to cigarette smoke but curtailed infiltration of neutrophils and macrophages in airways. Furthermore, this compound retarded thrombin-induced activation of PAR proteins and expression of inflammatory mediators in alveolar cells. Treating astragalin interrupted PAR proteins-activated reactive oxygen species production and MAPK signaling leading to alveolar inflammation. Accordingly, astragalin may interrupt the smoking-induced oxidative stress-MAPK signaling-inflammation axis via disconnection between alveolar PAR activation and pulmonary thromboembolism.

Tangeretin Ameliorates Glucose-Induced Podocyte Injury through Blocking Epithelial to Mesenchymal Transition Caused by Oxidative Stress and Hypoxia.

Podocyte injury inevitably results in leakage of proteins from the glomerular filter and is vital in the pathogenesis of diabetic nephropathy (DN). The underlying mechanisms of podocyte injury facilitate finding of new therapeutic targets for DN treatment and prevention. Tangeretin is an O-polymethoxylated flavone present in citrus peels with anti-inflammatory and antioxidant properties. This study investigated the renoprotective effects of tangeretin on epithelial-to-mesenchymal transition-mediated podocyte injury and fibrosis through oxidative stress and hypoxia caused by hyperglycemia. Mouse podocytes were incubated in media containing 33 mM glucose in the absence and presence of 1-20 µM tangeretin for up to 6 days. The in vivo animal model employed db/db mice orally administrated with 10 mg/kg tangeretin for 8 weeks. Non-toxic tangeretin inhibited glucose-induced expression of the mesenchymal markers of N-cadherin and α-smooth muscle actin in podocytes. However, the reduced induction of the epithelial markers of E-cadherin and P-cadherin was restored by tangeretin in diabetic podocytes. Further, tangeretin enhanced the expression of the podocyte slit diaphragm proteins of nephrin and podocin down-regulated by glucose stimulation. The transmission electron microscopic images revealed that foot process effacement and loss of podocytes occurred in diabetic mouse glomeruli. However, oral administration of 10 mg/kg tangeretin reduced urine albumin excretion and improved foot process effacement of diabetic podocytes through inhibiting loss of slit junction and adherenes junction proteins. Glucose enhanced ROS production and HIF-1α induction in podocytes, leading to induction of oxidative stress and hypoxia. Similarly, in diabetic glomeruli reactive oxygen species (ROS) production and HIF-1α induction were observed. Furthermore, hypoxia-evoking cobalt chloride induced epithelial-to-mesenchymal transition (EMT) process and loss of slit diaphragm proteins and junction proteins in podocytes, which was inhibited by treating submicromolar tangeretin. Collectively, these results demonstrate that tangeretin inhibited podocyte injury and fibrosis through blocking podocyte EMT caused by glucose-induced oxidative stress and hypoxia.

Aesculetin Attenuates Alveolar Injury and Fibrosis Induced by Close Contact of Alveolar Epithelial Cells with Blood-Derived Macrophages via IL-8 Signaling.

Pulmonary fibrosis is a disease in which lung tissues become fibrous and thereby causes severe respiratory disturbances. Various stimuli induce infiltration of macrophages to the respiratory tract, secreting inflammatory cytokines, which subsequently leads to the development of pulmonary fibrosis. Aesculetin, a major component of the sancho tree and chicory, is known to biologically have antioxidant and anti-inflammatory effects. Human alveolar epithelial A549 cells were cultured for 24 h in conditioned media of THP-1 monocyte-derived macrophages (mCM) with 1-20 µM aesculetin. Micromolar aesculetin attenuated the cytotoxicity of mCM containing inflammatory tumor necrosis factor-α (TNF)-α and interleukin (IL)-8 as major cytokines. Aesculetin inhibited alveolar epithelial induction of the mesenchymal markers in mCM-exposed/IL-8-loaded A549 cells (≈47-51% inhibition), while epithelial markers were induced in aesculetin-treated cells subject to mCM/IL-8 (≈1.5-2.3-fold induction). Aesculetin added to mCM-stimulated A549 cells abrogated the collagen production and alveolar epithelial CXC-chemokine receptor 2 (CXCR2) induction. The production of matrix metalloproteinase (MMP) proteins in mCM-loaded A549 cells was reduced by aesculetin (≈52% reduction), in parallel with its increase in tissue inhibitor of metalloproteinases (TIMP) proteins (≈1.8-fold increase). In addition, aesculetin enhanced epithelial induction of tight junction proteins in mCM-/IL-8-exposed cells (≈2.3-2.5-fold induction). The inhalation of polyhexamethylene guanidine (PHMG) in mice accompanied neutrophil predominance in bronchoalveolar lavage fluid (BALF) and macrophage infiltration in alveoli, which was inhibited by orally administrating aesculetin to mice. Treating aesculetin to mice alleviated PHMG-induced IL-8-mediated subepithelial fibrosis and airway barrier disruption. Taken together, aesculetin may antagonize pulmonary fibrosis and alveolar epithelial barrier disruption stimulated by the infiltration of monocyte-derived macrophages, which is typical of PHMG toxicity, involving interaction of IL-8 and CXCR2. Aesculetin maybe a promising agent counteracting macrophage-mediated inflammation-associated pulmonary disorders.

Aesculetin Inhibits Osteoclastic Bone Resorption through Blocking Ruffled Border Formation and Lysosomal Trafficking.

For the optimal resorption of mineralized bone matrix, osteoclasts require the generation of the ruffled border and acidic resorption lacuna through lysosomal trafficking and exocytosis. Coumarin-type aesculetin is a naturally occurring compound with anti-inflammatory and antibacterial effects. However, the direct effects of aesculetin on osteoclastogenesis remain to be elucidated. This study found that aesculetin inhibited osteoclast activation and bone resorption through blocking formation and exocytosis of lysosomes. Raw 264.7 cells were differentiated in the presence of 50 ng/mL receptor activator of nuclear factor-κB ligand (RANKL) and treated with 1-10 µM aesculetin. Differentiation, bone resorption, and lysosome biogenesis of osteoclasts were determined by tartrate-resistance acid phosphatase (TRAP) staining, bone resorption assay, Western blotting, immunocytochemical analysis, and LysoTracker staining. Aesculetin inhibited RANKL-induced formation of multinucleated osteoclasts with a reduction of TRAP activity. Micromolar aesculetin deterred the actin ring formation through inhibition of induction of αvß3 integrin and Cdc42 but not cluster of differentiation 44 (CD44) in RANKL-exposed osteoclasts. Administering aesculetin to RANKL-exposed osteoclasts attenuated the induction of autophagy-related proteins, microtubule-associated protein light chain 3, and small GTPase Rab7, hampering the lysosomal trafficking onto ruffled border crucial for bone resorption. In addition, aesculetin curtailed cellular induction of Pleckstrin homology domain-containing protein family member 1 and lissencephaly-1 involved in lysosome positioning to microtubules involved in the lysosomal transport within mature osteoclasts. These results demonstrate that aesculetin retarded osteoclast differentiation and impaired lysosomal trafficking and exocytosis for the formation of the putative ruffled border. Therefore, aesculetin may be a potential osteoprotective agent targeting RANKL-induced osteoclastic born resorption for medicinal use.

Involvement of synovial matrix degradation and angiogenesis in oxidative stress-exposed degenerative rotator cuff tears with osteoarthritis.

BACKGROUND: Shoulder osteoarthritis is a gradual wearing of the articular cartilage concomitant with degenerative rotator cuff tears (RCTs). This pathologic disorder is related to inflammation, oxidative stress, and angiogenesis. Degenerative alterations may prompt production of cytokines and angiogenesis-related proteins, evoking rotator cuff diseases. This study tested the hypothesis that oxidative stress-responsive mediators can influence joint inflammation of patients with RCT. METHODS: Twelve healthy RCT patients not suffering shoulder osteoarthritis were categorized as the control group, and 24 patients were allocated to 2 RCT groups (RCTP1 and RCTP2), according to severity of RCT and glenohumeral arthritis. Cytokines, growth factors, and angiogenic biomarkers in synovial fluids, blood, platelet-rich plasma (PRP), and tendon tissues were analyzed with enzyme-linked immunosorbent assay, immunoblotting, and collagen zymography. RESULTS: Induction of interleukin 8, tumor necrosis factor α, and interleukin 1ß was considerably elevated in synovial fluids of RCTP groups (P = .0398, P = .0428, P = .0828, respectively). The joint inflammation highly enhanced insulin-like growth factor 1 and transforming growth factor ß1 (TGF-ß1) in the synovial fluids and serum. Angiogenesis-related angiopoietin (Ang) 1 and 2, Tie-2, and hypoxia-inducible factor 1α were upregulated in reactive oxygen species-exposed RCTP synovium (P < .05). The production of matrix metalloproteinase 1 markedly increased in synovial fluids of the RCTP group (P = .043), whereas tissue collagen type I expression diminished with reduction of connective tissue growth factor expression (P = .032). Although the secretion of platelet-derived growth factor AB and vascular endothelial growth factor was marginal in the circulation (P = .714, P = .335), platelet-derived growth factor AB, TGF-ß1, Ang-1, and matrix metalloproteinase 1 were enriched in PRP of the RCTP group (P < .001, P = .002, P = .0389, respectively). CONCLUSIONS: Synovial matrix degradation and oxidative stress-triggered angiogenesis may be involved in inducing RCT with joint inflammation. TGF-ß1, Ang-1, and Ang-2 are the major components to repair RCT and to alleviate joint inflammation in PRP therapy.

Chrysin ameliorates podocyte injury and slit diaphragm protein loss via inhibition of the PERK-eIF2α-ATF-CHOP pathway in diabetic mice.

Glomerular epithelial podocytes are highly specialized cells that play a crucial role in maintaining normal function of the glomerular filtration barrier via their foot processes. Chrysin (5,7-dihydroxyflavone) is a natural flavonoid found in propolis and mushrooms that has anti-inflammatory, antioxidant and anticancer properties. This study aimed to evaluate the renoprotective effects of chrysin on podocyte apoptotic loss and slit diaphragm protein deficiency in high glucose-exposed podocytes and in db/db mouse kidneys. Exposure to high glucose (33 mmol/L) caused glomerular podocyte apoptosis in vitro, which was dose-dependently attenuated by nontoxic chrysin (1-20 µmol/L) through reduction of DNA fragmentation. Chrysin treatment dose-dependently restored the increased Bax/Bcl-2 ratio, and suppressed Apaf-1 induction and the elevated cytochrome c release in high glucose-exposed renal podocytes. In diabetic db/db mice, oral administration of chrysin (10 mg·kg-1·d-1, for 10 weeks) significantly attenuated proteinuria, and alleviated the abnormal alterations in glomerular ultrastructure, characterized by apoptotic podocytes and foot process effacement. In addition, this compound improved the induction of slit diaphragm proteins podocin/nephrin in the diabetic glomeruli. Exposure to high glucose elevated the unfolded protein response (UPR) to ER stress in renal podocytes, evidenced by up-regulation of PERK-eIF2α-ATF4-CHOP. Chrysin treatment blocked such ER stress responses pertinent to podocyte apoptosis and reduced synthesis of slit diaphragm proteins in vitro and in vivo. These observations demonstrate that targeting ER stress is an underlying mechanism of chrysin-mediated amelioration of diabetes-associated podocyte injury and dysfunction.

Rapid High Performance Liquid Chromatography Determination and Optimization of Extraction Parameters of the α-Asarone Isolated from Perilla frutescens L.

Response surface methodology (RSM), based on a central composite design, was used to determine the best liquid-to-raw material ratio (10:3-15 mL/g), extraction time (1-3 h), and ethanol concentration (50%-100%) for maximum content of α-asarone from Perilla frutescens (PF) extract. Experimental values of α-asarone were 9.51-46.36 mg/g; the results fitted a second-order quadratic polynomial model and correlated with the proposed model (R2 > 0.9354). The best conditions were obtained with extraction time of 1.76 h, liquid-to-raw material ratio of 10:13.5 mL/g, and ethanol concentration of 90.37%. Under these conditions, the model predicted extraction content of 40.56 mg/g, while experimental PF content of α-asarone was 43.84 mg/g dried plant. Optimized conditions determined for maximum content of α-asarone were similar to the experimental range. Experimental values agreed with those predicted, thus validating and indicating suitability of both the model and the RSM approach for optimizing extraction conditions. In addition, a reliable, reproducible and accurate method for the quantitative determination of α-asarone by High Performance Liquid Chromatography (HPLC) analysis was developed with limit of detection (LOD), limit of quantitation (LOQ) values of 0.10 and 0.29 µg/mL and excellent linearity (R2 > 0.9999).

Optimization of extraction parameters of PTP1ß (protein tyrosine phosphatase 1ß), inhibitory polyphenols, and anthocyanins from Zea mays L. using response surface methodology (RSM).

BACKGROUND: Protein tyrosine phosphatase expressed in insulin-sensitive tissues (such as liver, muscle, and adipose tissue) has a key role in the regulation of insulin signaling and pathway activation, making protein tyrosine phosphatase a promising target for the treatment of type 2 diabetes mellitus and obesity and response surface methodology (RSM) is an effective statistical technique for optimizing complex processes using a multi-variant approach. METHODS: In this study, Zea mays L. (Purple corn kernel, PCK) and its constituents were investigated for protein tyrosine phosphatase 1ß (PTP1ß) inhibitory activity including enzyme kinetic study and to improve total yields of anthocyanins and polyphenols, four extraction parameters, including temperature, time, solid-liquid ratio, and solvent volume, were optimized by RSM. RESULTS: Isolation of seven polyphenols and five anthocyanins was achieved by PTP1ß assay. Among them, cyanidin-3-(6"malonylglucoside) and 3'-methoxyhirsutrin showed the highest PTP1ß inhibition with IC50 values of 54.06 and 64.04 µM, respectively and 4.52 mg gallic acid equivalent/g (GAE/g) of total polyphenol content (TPC) and 43.02 mg cyanidin-3-glucoside equivalent/100 g (C3GE/100g) of total anthocyanin content (TAC) were extracted at 40 °C for 8 h with a 33 % solid-liquid ratio and a 1:15 solvent volume. Yields were similar to predictions of 4.58 mg GAE/g of TPC and 42.28 mg C3GE/100 g of TAC. CONCLUSION: These results indicated that PCK and 3'-methoxyhirsutrin and cyanidin-3-(6"malonylglucoside) might be active natural compounds and could be apply by optimizing of extraction process using response surface methodology.

Benzyl Isothiocyanate Inhibits Prostate Cancer Development in the Transgenic Adenocarcinoma Mouse Prostate (TRAMP) Model, Which Is Associated with the Induction of Cell Cycle G1 Arrest.

Benzyl isothiocyanate (BITC) is a hydrolysis product of glucotropaeolin, a compound found in cruciferous vegetables, and has been shown to have anti-tumor properties. In the present study, we investigated whether BITC inhibits the development of prostate cancer in the transgenic adenocarcinoma mouse prostate (TRAMP) mice. Five-week old, male TRAMP mice and their nontransgenic littermates were gavage-fed with 0, 5, or 10 mg/kg of BITC every day for 19 weeks. The weight of the genitourinary tract increased markedly in TRAMP mice and this increase was suppressed significantly by BITC feeding. H and E staining of the dorsolateral lobes of the prostate demonstrated that well-differentiated carcinoma (WDC) was a predominant feature in the TRAMP mice. The number of lobes with WDC was reduced by BITC feeding while that of lobes with prostatic intraepithelial neoplasia was increased. BITC feeding reduced the number of cells expressing Ki67 (a proliferation marker), cyclin A, cyclin D1, and cyclin-dependent kinase (CDK)2 in the prostatic tissue. In vitro cell culture results revealed that BITC decreased DNA synthesis, as well as CDK2 and CDK4 activity in TRAMP-C2 mouse prostate cancer cells. These results indicate that inhibition of cell cycle progression contributes to the inhibition of prostate cancer development in TRAMP mice treated with BITC.

Benzyl isothiocyanate suppresses high-fat diet-stimulated mammary tumor progression via the alteration of tumor microenvironments in obesity-resistant BALB/c mice.

We previously reported that a high-fat diet (HFD) and M2-macrophages induce changes in tumor microenvironments and stimulate tumor growth and metastasis of 4T1 mammary cancer cells in BALB/c mice. In this study, we attempted to determine whether benzyl isothiocyanate (BITC) inhibits HFD-induced changes in tumor progression and in tumor microenvironments. Four groups of female BALB/c mice (4-week-old) were fed on a control diet (CD, 10 kcal% fat) and HFD (60 kcal% fat) containing BITC (0, 25, or 100 mg/kg diet) for 20 weeks. Following 16 weeks of feeding, 4T1 cells (5×10(4) cells) were injected into the mammary fat pads, and animals were killed 30 d after the injection. HFD feeding increased solid tumor growth and the number of tumor nodules in the lung and liver, as compared to the CD group, and these increases were inhibited by BITC supplementation. The number of lipid vacuoles, CD45+ leukocytes and CD206+ M2-macrophages, expression of Ki67, levels of cytokines/chemokines, including macrophage-colony stimulating factor (M-CSF) and monocyte chemoattractant protein-1, and mRNA levels of F4/80, CD86, Ym1, CD163, CCR2, and M-CSF receptor were increased in the tumor tissues of HFD-fed mice, and these increases were inhibited by BITC supplementation. In vitro culture results demonstrated that BITC inhibited macrophage migration as well as lipid droplet accumulation in 3T3-L1 cells. These results suggest that suppression of lipid accumulation and macrophage infiltration in tumor tissues may be one of the mechanisms by which BITC suppresses tumor progression in HFD-fed mice.

Astragalin inhibits autophagy-associated airway epithelial fibrosis.

BACKGROUND: Fibrotic remodeling of airway and lung parenchymal compartments is attributed to pulmonary dysfunction with an involvement of reactive oxygen species (ROS) in chronic lung diseases such as idiopathic pulmonary fibrosis and asthma. METHODS: The in vitro study elucidated inhibitory effects of astragalin, kaempferol-3-O-glucoside from leaves of persimmon and green tea seeds, on oxidative stress-induced airway fibrosis. The in vivo study explored the demoting effects of astragalin on epithelial to mesenchymal transition in BALB/c mice sensitized with ovalbumin (OVA). RESULTS: The exposure of 20 µM H2O2 for 72 h accelerated E-cadherin loss and vimentin induction in airway epithelial BEAS-2B cells, which was reversed by non-toxic astragalin at 1-20 µM. Astragalin allayed the airway tissue levels of ROS and vimentin enhanced by OVA challenge. Collagen type 1 production increased in H2O2-exposed epithelial cells and collagen fiber deposition was observed in OVA-challenged mouse airways. This study further investigated that the oxidative stress-triggered autophagic regulation was responsible for inducing airway fibrosis. H2O2 highly enhanced the expression induction of the autophagy-related beclin-1 and light chains 3A/B (LC3A/B) within 4 h and astragalin blocked such induction by H2O2. This compound deterred the ROS-promoted autophagosome formation in BEAS-2B cells. Consistently, in OVA-sensitized mice the expression of beclin-1 and LC3A/B was highly induced, and oral administration of astragalin suppressed the autophagosome formation with inhibiting the induction of these proteins in OVA-challenged airway subepithelium. Induction of autophagy by spermidine influenced the epithelial induction of E-cadherin and vimentin that was blocked by treating astragalin. CONCLUSION: These results demonstrate that astragalin can be effective in allaying ROS-promoted bronchial fibrosis through inhibiting autophagosome formation in airways.

Dietary Compound Kaempferol Inhibits Airway Thickening Induced by Allergic Reaction in a Bovine Serum Albumin-Induced Model of Asthma.

Asthma is characterized by aberrant airways including epithelial thickening, goblet cell hyperplasia, and smooth muscle hypertrophy within the airway wall. The current study examined whether kaempferol inhibited mast cell degranulation and prostaglandin (PG) release leading to the development of aberrant airways, using an in vitro model of dinitrophenylated bovine serum albumin (DNP-BSA)-sensitized rat basophilic leukemia (RBL-2H3) mast cells and an in vivo model of BSA-challenged asthmatic mice. Nontoxic kaempferol at 10-20 µM suppressed ß-hexosaminidase release and cyclooxygenase 2 (COX2)-mediated production of prostaglandin D2 (PGD2) and prostaglandin F2α (PGF2α) in sensitized mast cells. Oral administration of ≤20 mg/kg kaempferol blocked bovine serum albumin (BSA) inhalation-induced epithelial cell excrescence and smooth muscle hypertrophy by attenuating the induction of COX2 and the formation of PGD2 and PGF2α, together with reducing the anti-α-smooth muscle actin (α-SMA) expression in mouse airways. Kaempferol deterred the antigen-induced mast cell activation of cytosolic phospholipase A2 (cPLA2) responsive to protein kinase Cµ (PKCµ) and extracellular signal-regulated kinase (ERK). Furthermore, the antigen-challenged activation of Syk-phospholipase Cγ (PLCγ) pathway was dampened in kaempferol-supplemented mast cells. These results demonstrated that kaempferol inhibited airway wall thickening through disturbing Syk-PLCγ signaling and PKCµ-ERK-cPLA2-COX2 signaling in antigen-exposed mast cells. Thus, kaempferol may be a potent anti-allergic compound targeting allergic asthma typical of airway hyperplasia and hypertrophy.

Inhibition of airway epithelial-to-mesenchymal transition and fibrosis by kaempferol in endotoxin-induced epithelial cells and ovalbumin-sensitized mice.

Chronic airway remodeling is characterized by structural changes within the airway wall, including smooth muscle hypertrophy, submucosal fibrosis and epithelial shedding. Epithelial-to-mesenchymal transition (EMT) is a fundamental mechanism of organ fibrosis, which can be induced by TGF-ß. In the in vitro study, we investigated whether 1-20 µM kaempferol inhibited lipopolysaccharide (LPS)-induced bronchial EMT in BEAS-2B cells. The in vivo study explored demoting effects of 10-20 mg/kg kaempferol on airway fibrosis in BALB/c mice sensitized with ovalbumin (OVA). LPS induced airway epithelial TGF-ß1 signaling that promoted EMT with concurrent loss of E-cadherin and induction of α-smooth muscle actin (α-SMA). Nontoxic kaempferol significantly inhibited TGF-ß-induced EMT process through reversing E-cadherin expression and retarding the induction of N-cadherin and α-SMA. Consistently, OVA inhalation resulted in a striking loss of epithelial morphology by displaying myofibroblast appearance, which led to bronchial fibrosis with submucosal accumulation of collagen fibers. Oral administration of kaempferol suppressed collagen deposition, epithelial excrescency and goblet hyperplasia observed in the lung of OVA-challenged mice. The specific inhibition of TGF-ß entailed epithelial protease-activated receptor-1 (PAR-1) as with 20 µM kaempferol. The epithelial PAR-1 inhibition by SCH-79797 restored E-cadherin induction and deterred α-SMA induction, indicating that epithelial PAR-1 localization was responsible for resulting in airway EMT. These results demonstrate that dietary kaempferol alleviated fibrotic airway remodeling via bronchial EMT by modulating PAR1 activation. Therefore, kaempferol may be a potential therapeutic agent targeting asthmatic airway constriction.

Tnfaip8 l1/Oxi-ß binds to FBXW5, increasing autophagy through activation of TSC2 in a Parkinson's disease model.

Abnormal autophagy may contribute to neurodegeneration in Parkinson's disease (PD). However, it is largely unknown how autophagy is dysregulated by oxidative stress (OS), one of major pathogenic causes of PD. We recently discovered the potential autophagy regulator gene family including Tnfaip8/Oxi-α, which is a mammalian target of rapamycin (mTOR) activator down-regulated by OS in dopaminergic neurons (J. Neurochem., 112, 2010, 366). Here, we demonstrate that the OS-induced Tnfaip8 l1/Oxi-ß could increase autophagy by a unique mechanism that increases the stability of tuberous sclerosis complex 2 (TSC2), a critical negative regulator of mTOR. Tnfaip8 l1/Oxi-ß and Tnfaip8/Oxi-α are the novel regulators of mTOR acting in opposition in dopaminergic (DA) neurons. Specifically, 6-hydroxydopamine (6-OHDA) treatment up-regulated Tnfaip8 l1/Oxi-ß in DA neurons, thus inducing autophagy, while knockdown of Tnfaip8 l1/Oxi-ß prevented significantly activation of autophagic markers by 6-OHDA. FBXW5 was identified as a novel binding protein for Tnfaip8 l1/Oxi-ß. FBXW5 is a TSC2 binding receptor within CUL4 E3 ligase complex, and it promotes proteasomal degradation of TSC2. Thus, Tnfaip8 l1/Oxi-ß competes with TSC2 to bind FBXW5, increasing TSC2 stability by preventing its ubiquitination. Our data show that the OS-induced Tnfaip8 l1/Oxi-ß stabilizes TSC2 protein, decreases mTOR phosphorylation, and enhances autophagy. Therefore, altered regulation of Tnfaip8 l1/Oxi-ß may contribute significantly to dysregulated autophagy observed in dopaminergic neurons under pathogenic OS condition. Dysfunctional autophagy is frequently observed in post-mortem brains of patients and animal models of Parkinson's disease. In dopaminergic neurons of the 6-hydroxydopamine (6-OHDA) model, oxidative stress induces Tnfaip8 l1/Oxi-ß, which results in increased autophagy by its exclusive binding with FBXW5 to stabilize TSC2. Thus, altered regulation of Tnfaip8 l1/Oxi-ß may contribute to dysregulated autophagy in dopaminergic neurons under pathogenic oxidative stress, implicating both Oxi-ß and FBXW5 as potential intervention targets for dysfunctional autophagy in dopaminergic neurons under oxidative stress.

Astragalin inhibits airway eotaxin-1 induction and epithelial apoptosis through modulating oxidative stress-responsive MAPK signaling.

BACKGROUND: Eotaxin proteins are a potential therapeutic target in treating the peribronchial eosinophilia associated with allergic airway diseases. Since inflammation is often associated with an increased generation of reactive oxygen species (ROS), oxidative stress is a mechanistically imperative factor in asthma. Astragalin (kaempferol-3-O-glucoside) is a flavonoid with anti-inflammatory activity and newly found in persimmon leaves and green tea seeds. This study elucidated that astragalin inhibited endotoxin-induced oxidative stress leading to eosinophilia and epithelial apoptosis in airways. METHODS: Airway epithelial BEAS-2B cells were exposed to lipopolysaccharide (LPS) in the absence and presence of 1-20 µM astragalin. Western blot and immunocytochemical analyses were conducted to determine induction of target proteins. Cell and nuclear staining was also performed for ROS production and epithelial apoptosis. RESULTS: When airway epithelial cells were exposed to 2 µg/ml LPS, astragalin nontoxic at ≤ 20 µM suppressed cellular induction of Toll-like receptor 4 (TLR4) and ROS production enhanced by LPS. Both LPS and H2O2 induced epithelial eotaxin-1 expression, which was blocked by astragalin. LPS activated and induced PLCγ1, PKCß2, and NADPH oxidase subunits of p22phox and p47phox in epithelial cells and such activation and induction were demoted by astragalin or TLR4 inhibition antagonizing eotaxin-1 induction. H2O2-upregulated phosphorylation of JNK and p38 MAPK was dampened by adding astragalin to epithelial cells, while this compound enhanced epithelial activation of Akt and ERK. H2O2 and LPS promoted epithelial apoptosis concomitant with nuclear condensation or caspase-3 activation, which was blunted by astragalin. CONCLUSIONS: Astragalin ameliorated oxidative stress-associated epithelial eosinophilia and apoptosis through disturbing TLR4-PKCß2-NADPH oxidase-responsive signaling. Therefore, astragalin may be a potent agent antagonizing endotoxin-induced oxidative stress leading to airway dysfunction and inflammation.

Berteroin present in cruciferous vegetables exerts potent anti-inflammatory properties in murine macrophages and mouse skin.

Berteroin (5-methylthiopentyl isothiocyanate) is a sulforaphane analog present in cruciferous vegetables, including Chinese cabbage, rucola salad leaves, and mustard oil. We examined whether berteroin exerts anti-inflammatory activities using lipopolysaccharide (LPS)-stimulated Raw 264.7 macrophages and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin inflammation models. Berteroin decreased LPS-induced release of inflammatory mediators and pro-inflammatory cytokines in Raw 264.7 macrophages. Berteroin inhibited LPS-induced degradation of inhibitor of κBα (IκBα) and nuclear factor-κB p65 translocation to the nucleus and DNA binding activity. Furthermore, berteroin suppressed degradation of IL-1 receptor-associated kinase and phosphorylation of transforming growth factor ß activated kinase-1. Berteroin also inhibited LPS-induced phosphorylation of p38 MAPK, ERK1/2, and AKT. In the mouse ear, berteroin effectively suppressed TPA-induced edema formation and down-regulated iNOS and COX-2 expression as well as phosphorylation of AKT and ERK1/2. These results demonstrate that berteroin exhibits potent anti-inflammatory properties and suggest that berteroin can be developed as a skin anti-inflammatory agent.