Sulforaphane Mitigates High-Fat Diet-Induced Obesity by Enhancing Mitochondrial Biogenesis in Skeletal Muscle via the HDAC8-PGC1α Axis.

SCOPE: Histone deacetylases (HDACs) play a crucial role in the transcriptional regulation of various genes which can contribute to metabolic disorders. Although sulforaphane (SFN), a natural HDAC inhibitor, has been reported to alleviate obesity in humans and mice, the specific mechanisms and how HDACs contribute to SFN's anti-obesity effects remain unclear. METHODS AND RESULTS: Oral administration of SFN in mice fed high-fat diet increases peroxisome proliferator activating receptor γ coactivator (PGC1α)-induced mitochondrial biogenesis in skeletal muscle. Among HDACs, SFN specifically inhibits HDAC8 activity. SFN enhances mitochondrial DNA and adenosine triphosphate (ATP) production in C2C12 myotubes, similar to the action of PCI34051, a synthetic HDAC8-specific inhibitor. These effects are mediated by increased expression of PGC1α via upregulation of cAMP response element binding (CREB, Ser133 ) phosphorylation and p53 (Lys379 ) acetylation. These SFN-induced effects are not observed in cells with a genetic deletion of HDAC8, suggesting the existence of a regulatory loop between HDAC8 and PGC1α in SFN's action. CONCLUSION: SFN prevents obesity-related metabolic dysregulation by enhancing mitochondrial biogenesis and function via targeting the HDAC8-PGCα axis. These results suggest SFN as a beneficial anti-obesity agent providing new insight into the role of HDAC8 in the PGC1α-mediated mitochondrial biogenesis, which may be a novel and promising drug target for metabolic diseases.

Discovery and optimized extraction of the anti-osteoclastic agent epicatechin-7-O-ß-D-apiofuranoside from Ulmus macrocarpa Hance bark.

Ulmus macrocarpa Hance bark (UmHb) has been used as a traditional herbal medicine in East Asia for bone concern diseases for a long time. To find a suitable solvent, we, in this study, compared the efficacy of UmHb water extract and ethanol extract which can inhibit osteoclast differentiation. Compared with two ethanol extracts (70% and 100% respectively), hydrothermal extracts of UmHb more effectively inhibited receptor activators of nuclear factor κB ligand-induced osteoclast differentiation in murine bone marrow-derived macrophages. We identified for the first time that (2R,3R)-epicatechin-7-O-ß-D-apiofuranoside (E7A) is a specific active compound in UmHb hydrothermal extracts through using LC/MS, HPLC, and NMR techniques. In addition, we confirmed through TRAP assay, pit assay, and PCR assay that E7A is a key compound in inhibiting osteoclast differentiation. The optimized condition to obtain E7A-rich UmHb extract was 100 mL/g, 90 °C, pH 5, and 97 min. At this condition, the content of E7A was 26.05 ± 0.96 mg/g extract. Based on TRAP assay, pit assay, PCR, and western blot, the optimized extract of E7A-rich UmHb demonstrated a greater inhibition of osteoclast differentiation compared to unoptimized. These results suggest that E7A would be a good candidate for the prevention and treatment of osteoporosis-related diseases.

Enhancing stability and bioavailability of sulforaphene in radish seed extracts using nanoemulsion made with high oleic sunflower oil.

The effect of nanoemulsions on the stability and bioavailability of sulforaphene (SFEN) in radish seed extract (RSE) was investigated. Four types of oil were used as lipid ingredients of the nanoemulsions: soybean, high oleic acid sunflower, coconut, and hydrogenated palm oils. SFEN in RSE nanoemulsions showed greater stability to temperature, acid, and alkaline conditions than SFEN in RSE suspended in water (RSE-S). Particularly under alkaline conditions, the half-life of SFEN in the nanoemulsion with high oleic sunflower oil (RSE-HOSO) was 8 times longer than that of RSE-S. Furthermore, in the pharmacokinetics study, it was observed that AUC0-8 increased and oral clearance (CL/F) decreased significantly in rats orally administered RSE-HOSO compared with RSE-S (p < 0.05). This study indicates that the type of oil used in nanoemulsions affects the stability and bioavailability of SFEN in RSE. These results may provide a guideline for the development of functional foods containing RSE. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01304-2.

Ca2+-Permeable TRPV1 Receptor Mediates Neuroprotective Effects in a Mouse Model of Alzheimer's Disease via BDNF/CREB Signaling Pathway.

Transient receptor potential vanilloid 1 (TRPV1) protein is a Ca2+-permeable non-selective cation channel known for its pain modulation pathway. In a previous study, it was discovered that a triple-transgenic Alzheimer's disease (AD) mouse model (3xTg-AD+/+) has anti-AD effects. The expression of proteins in the brain-derived neurotrophic factor (BDNF)/cAMP response element binding protein (CREB) pathway in a 3xTg-AD/TRPV1 transgenic mice model was investigated to better understand the AD regulatory effect of TRPV1 deficiency. The results show that TRPV1 deficiency leads to CREB activation by increasing BDNF levels and promoting phosphorylation of tyrosine receptor kinase B (TrkB), extracellular signal-regulated kinase (ERK), protein kinase B (Akt), and CREB in the hippocampus. Additionally, TRPV1 deficiency-induced CREB activation increases the antiapoptotic factor B-cell lymphoma 2 (Bcl-2) gene, which consequently downregulates Bcl-2-associated X (Bax) expression and decreases cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP), which leads to the prevention of hippocampal apoptosis. In conclusion, TRPV1 deficiency exhibits neuroprotective effects by preventing apoptosis through the BDNF/CREB signal transduction pathway in the hippocampus of 3xTg-AD mice.

Glycine max Fermented by a Novel Probiotic, Bifidobacterium animalis subsp. lactis LDTM 8102, Increases Immuno-Modulatory Function.

Many probiotic species have been used as a fermentation starter for manufacturing functional food materials. We have isolated Bifidobacterium animalis subsp. lactis LDTM 8102 from the feces of infants as a novel strain for fermentation. While Glycine max has been known to display various bioactivities including anti-oxidant, anti-skin aging, and anti-cancer effects, the immune-modulatory effect of Glycine max has not been reported. In the current study, we have discovered that the extract of Glycine max fermented with B. animalis subsp. lactis LDTM 8102 (GFB 8102), could exert immuno-modulatory properties. GFB 8102 treatment increased the production of immune-stimulatory cytokines in RAW264.7 macrophages without any noticeable cytotoxicity. Analysis of the molecular mechanism revealed that GFB 8102 could upregulate MAPK2K and MAPK signaling pathways including ERK, p38, and JNK. GFB 8102 also increased the proliferation rate of splenocytes isolated from mice. In an animal study, administration of GFB 8102 partially recovered cyclophosphamide-mediated reduction in thymus and spleen weight. Moreover, splenocytes from the GFB 8102-treated group exhibited increased TNF-α, IL-6, and IL-1ß production. Based on these findings, GFB 8102 could be a promising functional food material for enhancing immune function.

Ethanol Extract of Yak-Kong Fermented by Lactic Acid Bacteria from a Korean Infant Markedly Reduces Matrix Metallopreteinase-1 Expression Induced by Solar Ultraviolet Irradiation in Human Keratinocytes and a 3D Skin Model.

Yak-Kong is a type of black soybean that is colloquially referred to as the "medicinal bean" and it elicits several beneficial effects that are relevant to human health, including attenuating the formation of skin wrinkles. It has previously been shown that soybean extracts elicit additional bioactivity that is fermented by lactic acid bacteria. In this study of lactic acid bacteria strains that were isolated from the stools of breast-feeding infants (<100 days old), we selected Bifidobacterium animalis subsp. Lactis LDTM 8102 (LDTM 8102) as the lead strain for the fermentation of Yak-Kong. We investigated the effects of LDTM 8102-fermented Yak-Kong on solar-ultraviolet irradiation (sUV)-induced wrinkle formation. In HaCaT cells, the ethanol extract of LDTM 8102-fermented Yak-Kong (EFY) effectively reduced sUV-induced matrix metalloproteinase-1 (MMP-1) secretion. The effect of EFY was superior to that of unfermented (UFY)- and Lactis KCTC 5854 (another Bifidobacterium animalis species)-fermented Yak-Kong. Additionally, EFY reduced sUV-induced MMP-1 mRNA expression and promoter activity, as well as the transactivation of AP-1 and phosphorylation of ERK1/2 and JNK1/2. Furthermore, EFY alleviated sUV-induced MMP-1 secretion, the destruction of the epidermis, and degradation of collagen in a three-dimensional (3D) skin culture model. EFY had a higher total polyphenol content and anti-oxidative activity than UFY. Twelve metabolites were significantly (≥2-fold) increased in Yak-Kong extract after fermentation by LDTM 8102. Among them, the metabolites of major isoflavones, such as 6,7,4'-trihydroxyisoflavone (THIF), exerted the reducing effect of MMP-1, which indicated that the isoflavone metabolites contributed to the effect of EFY on MMP-1 expression as active compounds. These findings suggest that EFY is a potent natural material that can potentially prevent sUV-induced wrinkle formation.

Orobol, A Derivative of Genistein, Inhibits Heat-Killed Propionibacterium acnes-Induced Inflammation in HaCaT Keratinocytes.

Acne is a chronic skin disease that typically occurs in the teens and twenties, and its symptoms vary according to age, sex, diet, and lifestyle. The condition is characterized by hyperproliferation of keratinocytes in the epidermis, sebum overproduction, excessive growth of Propionibacterium acnes, and P. acnes-induced skin inflammation. Interleukin (IL)-1α and IL-6 are predominant in the inflammatory lesions of acne vulgaris. These cytokines induce an inflammatory reaction in the skin in the presence of pathogens or stresses. Moreover, IL-1α accelerates the production of keratin 16, which is typically expressed in wounded or aberrant skin, leading to abnormalities in architecture and hyperkeratinization. Orobol (3',4',5,7-tetrahydroxyisoflavone) is a metabolite of genistein that inhibited the P. acnes-induced increases in IL-6 and IL-1α levels in human keratinocytes (HaCaTs) more effectively compared with salicylic acid. In addition, orobol decreased the IL-1α and IL-6 mRNA levels and inhibited the phosphorylation of inhibitor of kappa-B kinase, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha, and mitogen-activated protein kinase induced by P. acnes. Finally, the expression of Ki67 was decreased by orobol. Thus, orobol ameliorated the inflammation and hyperkeratinization induced by heat-killed P. acnes and thus has potential for use in functional foods and cosmetics.

A major daidzin metabolite 7,8,4'-trihydroxyisoflavone found in the plasma of soybean extract-fed rats attenuates monocyte-endothelial cell adhesion.

Among many functional foods and their phytochemicals, ingestion of soybean (Glycine max) is highly correlated to reduced risk of cardiovascular diseases. Validation of potential health benefits of functional foods requires information about the bioavailability and metabolism of bioactive compounds. In this context, several phase I and II metabolites of isoflavones were target-analyzed in the plasma of rats acutely supplemented with soybean embryo extract. A daidzein metabolite, 7,8,4'-trihydroxyisoflavone (7,8,4'-THI), was found to have the highest average area under curve value (574.3±112.8). Therefore, its potential prevention effect on atherosclerosis was investigated using monocyte-endothelial cell adhesion assay. Different from its precursor daidzein or daidzin, 7,8,4'-THI attenuated adhesion of THP-1 monocytes to tumor necrosis factor-alpha (TNF-α) stimulated human umbilical vein endothelial cells (HUVECs). In addition, 7,8,4'-THI significantly downregulated TNF-α stimulated the expression of vascular cell adhesion molecule-1 and monocyte chemotactic protein-1 and phosphorylation of IκB kinase and IκBα involved in the initiation of atherosclerosis in HUVECs. Therefore, 7,8,4'-THI, a highly bioavailable hydroxylated isoflavone metabolite, has potential anti-atherosclerotic effect via inhibiting monocyte-endothelial adhesion.

5-(3',4'-Dihydroxyphenyl-γ-valerolactone), a Major Microbial Metabolite of Proanthocyanidin, Attenuates THP-1 Monocyte-Endothelial Adhesion.

Several metabolomics of polymeric flavan-3-ols have reported that proanthocyanidins are extensively metabolized by gut microbiota. 5-(3',4'-dihydroxyphenyl)-γ-valerolactone (DHPV) has been reported to be the major microbial metabolite of proanthocyanidins. We demonstrated that DHPV has stronger prevention effect on tumor necrosis factor (TNF)-α-stimulated adhesion of THP-1 human monocytic cells to human umbilical vein endothelial cells compared to its potential precursors such as procyanidin A1, A2, B1 and B2, (+)catechin, (-)epicatechin and its microbial metabolites such as 3-(3,4-dihydroxyphenyl)propionic acid and 2-(3,4-dihydroxyphenyl)acetic acid. Mechanism study showed that DHPV prevents THP-1 monocyte-endothelial cell adhesion by downregulating TNF-α-stimulated expressions of the two biomarkers of atherosclerosis such as vascular cell adhesion molecule-1 and monocyte chemotactic protein-1, activation of nuclear factor kappa B transcription and phosphorylation of I kappa-B kinase and IκBα. We suggested that DHPV has higher potentiality in prevention of atherosclerosis among the proanthocyanidin metabolites.

3,3'-Diindolylmethane suppresses high-fat diet-induced obesity through inhibiting adipogenesis of pre-adipocytes by targeting USP2 activity.

SCOPE: Indole-3-carbinol (I3C), a derivative abundant in cruciferous vegetables such as cabbage, is well known for its various health benefits such as chemo-preventive and anti-obesity effects. I3C is easily metabolized to 3,3'-diindolylmethane (DIM), a more stable form, in acidic conditions of the stomach. However, the anti-obesity effect of DIM has not been investigated clearly. We sought to investigate the effect of DIM on diet-induced obesity and to elucidate its underlying mechanisms. METHODS AND RESULTS: High-fat diet (HFD)-fed obese mouse and MDI-induced 3T3-L1 adipogenesis models were used to study the effect of DIM. We observed that the administration of DIM (50 mg/kg BW) significantly suppressed HFD-induced obesity, associated with a decrease in adipose tissue. Additionally, we observed that DIM treatment (40 and 60 µM), but not I3C treatment, significantly inhibited MDI-induced adipogenesis by reducing the levels of several adipogenic proteins such as PPAR-γ and C/EBPα. DIM, but not I3C, suppressed cell cycle progression in the G1 phase, which occurred in the early stage of adipogenesis, inducing post-translational degradation of cyclin D1 by inhibiting ubiquitin specific peptidase 2 (USP2) activities. CONCLUSION: Our findings indicate that cruciferous vegetables, which can produce DIM as a metabolite, have the potential to prevent or treat chronic obesity.

Absence of 4-1BB reduces obesity-induced atrophic response in skeletal muscle.

Obesity-induced inflammation causes skeletal muscle atrophy accompanied by disruption of oxidative metabolism and is implicated in metabolic complications such as insulin resistance and type 2 diabetes. We previously reported that 4-1BB, a member of the tumor necrosis factor receptor superfamily, participated in obesity-induced skeletal muscle inflammation. Here, we show that the absence of 4-1BB in obese mice fed a high-fat diet led to a decrease in expression of atrophic factors (MuRF1 and Atrogin-1) with suppression of NF-κB activity, and that this was accompanied by increases in mitochondrial oxidative metabolic genes/proteins (e.g., PGC-1α, CPT1ß, etc.) expression and oxidative muscle fibers marker genes/proteins in the skeletal muscle. These findings suggest that 4-1BB-mediated inflammatory signaling could be a potential target for combating obesity-related muscle atrophy and metabolic derangement in skeletal muscle.

Gingerenone A, a polyphenol present in ginger, suppresses obesity and adipose tissue inflammation in high-fat diet-fed mice.

SCOPE: Ginger exerts protective effects on obesity and its complications. Our objectives here are to identify bioactive compounds that inhibit adipogenesis and lipid accumulation in vitro, elucidate the anti-obesity effect of gingerenone A (GA) in diet-induced obesity (DIO), and investigate whether GA affects adipose tissue inflammation (ATI). METHODS AND RESULTS: Oil red O staining showed that GA had the most potent inhibitory effect on adipogenesis and lipid accumulation in 3T3-L1 cells among ginger components tested at a single concentration (40 µM). Consistent with in vitro data, GA attenuates DIO by reducing fat mass in mice. This was accompanied by a modulation of fatty acid metabolism via activation of AMP-activated protein kinase (AMPK) in vitro and in vivo. Additionally, GA suppressed ATI by inhibiting macrophage recruitment and downregulating pro-inflammatory cytokines. CONCLUSION: These results suggest that GA may be used as a potential therapeutic candidate for the treatment of obesity and its complications by suppressing adipose expansion and inflammation.

Dietary oleuropein inhibits tumor angiogenesis and lymphangiogenesis in the B16F10 melanoma allograft model: a mechanism for the suppression of high-fat diet-induced solid tumor growth and lymph node metastasis.

Previously, we reported that high-fat-diet (HFD)-induced obesity stimulates melanoma progression in the B16F10 allograft model. In this study, we examined whether oleuropein (OL), the most abundant phenolic compound in olives, inhibits HFD-induced melanoma progression. Four-week-old male C57BL/6N mice were fed a HFD-diet with or without OL. After 16 weeks of feeding, B16F10-luc cells were subcutaneously injected and the primary tumor was resected 3 weeks later. OL suppressed HFD-induced solid tumor growth. In the tumor tissues, OL reduced HFD-induced expression of angiogenesis (CD31, VE-cadherin, VEGF-A, and VEGFR2), lymphangiogenesis (LYVE-1, VEGF-C, VEGF-D, and VEGFR3), and hypoxia (HIF-1α and GLUT-1) markers as well as HFD-induced increases in lipid vacuoles and M2 macrophages (MΦs). All animals were euthanized 2.5 weeks after tumor resection. OL suppressed HFD-induced increases in lymph node (LN) metastasis; expression of VEGF-A, VEGF-C, and VEGF-D in the LN; and M2-MΦs and the size of adipocytes in adipose tissues surrounding LNs. Co-culture results revealed that the crosstalk between B16F10s, M2-MΦs, and differentiated 3T3-L1 cells under hypoxic conditions increased the secretion of VEGF-A and -D, which stimulated tube formation and migration of endothelial cells (HUVECs) and lymphatic endothelial cells (LEC), respectively. Additionally, OL directly inhibited the differentiation of 3T3-L1 preadipocytes and tube formation by HUVECs and LECs. The overall results indicated that dietary OL inhibits lipid and M2-MΦ accumulation in HFD-fed mice, which contributes to decreases in VEGF secretion, thereby leading to inhibition of angiogenesis and lymphangiogenesis.

A Combination of Soybean and Haematococcus Extract Alleviates Ultraviolet B-Induced Photoaging.

Soybean-derived isoflavones have been investigated for their preventative effects against UV-induced symptoms of skin damage including wrinkle formation and inflammation. Haematococcus pluvialis is a freshwater species of Chlorophyta that contains high concentrations of the natural carotenoid pigment astaxanthin. Astaxanthin is known to be involved in retinoic acid receptor (RAR) signaling and previously been associated with the inhibition of activator protein (AP)-1 dependent transcription. Based on previous studies, we hypothesized that a combination of soy extract (SE) and Haematococcus extract (HE) may prevent UVB-induced photoaging through specific signaling pathways, as measured by UVB-induced wrinkling on hairless mice skin and expression changes in human dermal fibroblasts (HDFs). The 1:2 ratio of SE and HE mixture (SHM) showed the optimal benefit in vivo. SHM was found to inhibit wrinkle formation via the downregulation of matrix metalloproteinase (MMP)-1 mRNA and protein expression. SHM also inhibited mitogen-activated protein kinase (MAPK) phosphorylation and the transactivation of AP-1 which plays an important role in regulating MMP expression. These results highlight the potential for SHM to be developed as a therapeutic agent to prevent UVB-induced skin wrinkling.

Methionine deprivation suppresses triple-negative breast cancer metastasis in vitro and in vivo.

Nutrient deprivation strategies have been proposed as an adjuvant therapy for cancer cells due to their increased metabolic demand. We examined the specific inhibitory effects of amino acid deprivation on the metastatic phenotypes of the human triple-negative breast cancer (TNBC) cell lines MDA-MB-231 and Hs 578T, as well as the orthotopic 4T1 mouse TNBC tumor model. Among the 10 essential amino acids tested, methionine deprivation elicited the strongest inhibitory effects on the migration and invasion of these cancer cells. Methionine deprivation reduced the phosphorylation of focal adhesion kinase, as well as the activity and mRNA expression of matrix metalloproteinases MMP-2 and MMP-9, two major markers of metastasis, while increasing the mRNA expression of tissue inhibitor of metalloproteinase 1 in MDA-MB-231 cells. Furthermore, methionine restriction downregulated the metastasis-related factor urokinase plasminogen activatior and upregulated plasminogen activator inhibitor 1 mRNA expression. Animals on the methionine-deprived diet showed lower lung metastasis rates compared to mice on the control diet. Taken together, these results suggest that methionine restriction could provide a potential nutritional strategy for more effective cancer therapy.

Licoricidin, an Active Compound in the Hexane/Ethanol Extract of Glycyrrhiza uralensis, Inhibits Lung Metastasis of 4T1 Murine Mammary Carcinoma Cells.

Licorice extracts containing glycyrrhizin exhibit anti-carcinogenic properties. Because glycyrrhizin induces severe hypokalemia and hypertension, we prepared a hexane/ethanol extract of Glycyrrhiza uralensis (HEGU) that lacks glycyrrhizin, and showed that HEGU induces apoptosis and G1 cell cycle arrest and inhibits migration of DU145 human prostate cancer cells. Our previous in vitro studies identified two active components in HEGU: isoangustone A, which induces apoptosis and G1 cycle arrest, and licoricidin, which inhibits metastasis. This study examined whether HEGU and licoricidin inhibit metastasis using the 4T1 mammary cancer model. Both HEGU and licoricidin treatment reduced pulmonary metastasis and the expression of CD45, CD31, HIF-1α, iNOS, COX-2, and VEGF-A in tumor tissues. Additionally, a decrease in protein expression of VEGF-R2, VEGF-C, VEGF-R3, and LYVE-1 was noted in tumor tissues of licoricidin-treated mice. Furthermore, the blood concentrations of MMP-9, ICAM-1, VCAM-1, and VEGF-A were decreased in HEGU-treated mice. In vitro 4T1 cell culture results showed that both HEGU and licoricidin inhibited cell migration, MMP-9 secretion, and VCAM expression. The present study demonstrates that the licoricidin in HEGU inhibits lung metastasis of 4T1 mammary carcinoma cells, which may be mediated via inhibition of cancer cell migration, tumor angiogenesis, and lymphangiogenesis.

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.

Resveratrol Suppresses Cytokine Production Linked to FcεRI-MAPK Activation in IgE-Antigen Complex-Exposed Basophilic Mast Cells and Mice.

A complicated interplay between resident mast cells and other recruited inflammatory cells contributes to the development and progression of allergic inflammation entailing the promotion of T helper 2 (Th2) cytokine responses. The current study examined whether resveratrol suppressed the production of inflammatory Th2 cytokines in cultured rat basophilic leukemia RBL-2H3 cells. Cells pre-treated with resveratrol nontoxic at 1­25 µM were sensitized with anti-dinitrophenyl (anti-DNP), and subsequently stimulated by dinitrophenyl-human serum albumin (DNP­HSA) antigen. Resveratrol dose-dependently diminished the secretion of interleukin (IL)-3, IL-4, IL-13 as well as tumor necrosis factor (TNF)-α by the antigen stimulation from sensitized cells. It was found that resveratrol mitigated the phosphorylation of p38 MAPK, ERK, and JNK elevated in mast cells exposed to Fc epsilon receptor I (FcεRI)-mediated immunoglobulin E (IgE)-antigen complex. The FcεRI aggregation was highly enhanced on the surface of mast cells following the HSA stimulation, which was retarded by treatment with 1­25 µM resveratrol. The IgE-receptor engagement rapidly induced tyrosine phosphorylation of c-Src-related focal adhesion protein paxillin involved in the cytoskeleton rearrangement. The FcεRI-mediated rapid activation of c-Src and paxillin was attenuated in a dose-dependent manner. In addition, the paxillin activation entailed p38 MAPK and ERK-responsive signaling, but the JNK activation was less involved. Consistently, oral administration of resveratrol reduced the tissue level of phosphorylated paxillin in the dorsal skin of DNP­HSA-challenged mice. The other tyrosine kinase Tyk2-STAT1 signaling was activated in the dorsal epidermis of antigen-exposed mice, which was associated with allergic inflammation. These results showed that resveratrol inhibited Th2 cytokines- and paxillin-linked allergic responses dependent upon MAPK signaling. Therefore, resveratrol may possess the therapeutic potential of targeting mast cells in preventing the development of allergic inflammation.

Estrogen deprivation and excess energy supply accelerate 7,12-dimethylbenz(a)anthracene-induced mammary tumor growth in C3H/HeN mice.

BACKGROUND/OBJECTIVES: Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS: Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS: Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS: These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice.

Inhibition of tumor progression by oral piceatannol in mouse 4T1 mammary cancer is associated with decreased angiogenesis and macrophage infiltration.

Piceatannol, a polyphenol which exhibits anticancer activities, is found in grapes, red wine and berries. It has been shown to inhibit several transcription factor pathways. The present study was conducted to determine whether oral administration of piceatannol inhibits mammary tumor progression. 4T1 mammary carcinoma cells were injected into the mammary fat pad of syngeneic female BALB/c mice. Starting 1 day later, piceatannol (10- or 20-mg/kg body weight/day) was administered by oral gavage for 30 days. Piceatannol treatment reduced tumor growth. In tumor tissues, piceatannol treatment reduced the expression of transcription factors P-NFκB p65, P-STAT3 and HIF-1α and multiple proteins involved in regulation of cell cycle progression (Ki67, cyclin D1, cyclin A, CDK2, CDK4), angiogenesis (VEGF-A, VEGFR-2, VE-cadherin, CD31) and lymphangiogenesis (VEGF-C, LYVE-1), as well as macrophage infiltration. Piceatannol significantly increased apoptotic cells and expression of both Bax and cleaved caspase-3 but reduced Bcl-2 expression in tumor tissues. In addition, piceatannol reduced the number and volume of pulmonary tumor nodules and expression of MMP-9 in both lung and tumor. It also reduced tissue levels of cytokines/chemokines, including M-CSF and MCP-1. In vitro results revealed that piceatannol inhibited migration of 4T1 cells and monocytes, as well as secretion of MCP-1 and M-CSF by 4T1 cells. 4T1 cell-conditioned medium stimulated monocyte migration, which was suppressed by a CCR2 antibody. These results indicate that alteration in tumor microenvironment (macrophages, transcription factors, etc.) is an important mechanism by which piceatannol inhibits tumor proliferation, angiogenesis and lymphangiogenesis, leading to suppression of mammary tumor growth and metastasis.