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Di-(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in polyvinyl chloride products. DEHP exposure in humans is of great concern due to its endocrine-disrupting properties. In this study, we characterized the agonistic activities of DEHP and its five metabolites, mono-(2-ethylhexyl) phthalate (MEHP), 5OH-MEHP, 5oxo-MEHP, 5cx-MEPP and 2cx-MMHP against human nuclear receptors, peroxisome proliferator-activated receptor α (PPARα), pregnane X receptor (PXR), and constitutive androstane receptor (CAR) using transactivation assays. In the PPARα assay, the order of the agonistic activity was MEHP >> 5cx-MEPP >5OH-MEHP, 5oxo-MEHP >2cx-MMHP > DEHP, with DEHP significantly inhibiting MEHP-induced PPARα agonistic activity. This finding was compared to the results from in silico docking simulation. In the PXR assay, DEHP showed PXR agonistic activity more potent than that of MEHP, whereas the other metabolites showed little activity. In the CAR assay, none of the tested compounds showed agonistic activity. Moreover, the expression levels of PPARα-, PXR-, and CAR-target genes in HepaRG cells exposed to DEHP or MEHP were investigated using qRT-PCR analysis. As a result, exposure to these compounds significantly upregulated PXR/CAR target genes (CYP3A4 and CYP2B6), but not PPARα target genes (CYP4A11, etc.) in HepaRG cells. Taken together, these results suggest that direct PXR and/or indirect CAR activation by several DEHP metabolites may be involved in the endocrine disruption by altering hormone metabolism., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Hiroyuki Kojima reports financial support was provided by Japan Society for the Promotion of Science. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Inflammatory bowel disease (IBD) is characterized by chronic intestinal inflammation and its treatment varies widely; however, when inflammation is high, a complete nutrient containing pre-digested elemental diet (ED) is used to preserve the intestinal tract. In this study, we investigated the mechanisms underlying the effectiveness of EDs for IBD using mice. C57BL/6 mice were orally treated with the ED (5 mL/day) and its ingredient L-tryptophan (Trp) (1-100 mg/kg), respectively. Flow cytometry analysis revealed that treatment with the ED and Trp (10 and 100 mg/kg) significantly increased the percentage of splenic CD4+-/CD25+-/Foxp3+ regulatory T cells (Tregs). In the 2% DSS-induced colitis-mouse model, Trp administration (100 mg/kg) led to a significant decrease in TNF-α and increase in IL-10 in the serum as well as a significant decrease in the inflammation score. Furthermore, the aryl hydrocarbon receptor (AhR) agonistic activity, which is a key function of Treg induction, of Trp and 15 Trp metabolites was characterized using a highly sensitive DR-EcoScreen cell assay. Five Trp metabolites, including L-kynurenine, acted as AhR agonists, while Trp did not. Taken together, these results suggest that the ED treatment has a Trp-dependent immunoregulatory effect, and several Trp metabolites that activate the AhR might contribute to induction of remission in patients with IBD.

Perfluorooctanoic acid (PFOA), a synthetic perfluorinated eight-carbon organic chemical, induces hepatotoxicity in rodents, indicated increased liver weight, hepatocellular hypertrophy, necrosis, and peroxisome proliferation. Epidemiological studies have demonstrated the association between serum PFOA levels and various adverse effects. In this study, we investigated the gene expression profiles of human HepaRG cells exposed to 10 and 100 μM PFOA for 24 h. Treatment with 10 and 100 μM PFOA significantly modulated the expression of 190 and 996 genes, respectively. Genes upregulated or downregulated by 100 µM PFOA included peroxisome proliferator-activated receptor (PPAR) signaling genes related to lipid metabolism, adipocyte differentiation, and gluconeogenesis. Moreover, we identified the "Nuclear receptors-meta pathways" following the activation of other nuclear receptors: constitutive androstane receptor (CAR), pregnane X receptor (PXR) and farnesoid X receptor (FXR), as well as the transcription factor nuclear factor E2-related factor 2 (Nrf2). The expression levels of some target genes (CYP4A11, CYP2B6, CYP3A4, CYP7A1, and GPX2) of these nuclear receptors and Nrf2 were confirmed using quantitative reverse transcription polymerase chain reaction. Next, we performed transactivation assays using COS-7 and HEK293 cells to investigate whether these signaling-pathways were activated by the direct effects of PFOA on human PPARα, CAR, PXR, FXR and Nrf2. PFOA concentration-dependently activated PPARα, but not CAR, PXR, FXR, or Nrf2. Taken together, these results suggest that PFOA affects the hepatic transcriptomic responses of HepaRG cells through the direct activation of PPARα and indirect activation of CAR, PXR, FXR, and Nrf2. Our finding indicates that PPARα activation in the "Nuclear receptors-meta pathways" functions as a molecular initiating event for PFOA, and indirect activation of alternative nuclear receptors and Nrf2 also induce important molecular mechanisms in PFOA-induced human hepatotoxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Fucoxanthin (Fx) is a critical pigment required for photosynthesis in brown algae and microalgae. Fx is also a dietary marine carotenoid that with potent anticancer activity in vitro and in vivo. Some popular light meals for increased satiety, such as biscuits, cereals, and crackers, are frequently fortified with micronutrients for human health benefits. However, data on the anticancer potential of Fx-supplemented light meals in humans and animal models remain limited. In the present study, we investigated the anticancer effects of a Fx-supplemented biscuit using a carcinogenic murine azoxymethane/dextran sodium sulfate (AOM/DSS) model. We observed that periodic administration of biscuits containing 0.3% Fx (Fx-biscuit) at an interval of 3 days (each 15 h) per week for 15 weeks significantly inhibited colorectal carcinogenesis in AOM/DSS mice. Comprehensive gene analysis demonstrated that the Fx-biscuit significantly altered the expression of 138 genes in the colorectal mucosal tissue of the mice. In particular, the expression of heat shock protein 70 (HSP70) genes, Hspa1b (-35.7 - fold) and Hspa1a (-34.9 - fold), was markedly downregulated. HSP70 is a polyfunctional chaperone protein that is involved in cancer development. Compared to the control-biscuit group, the number of cells with markedly high fluorescence for HSP70 protein (HSP70 high ) in colorectal mucosal crypts and adenocarcinomas significantly reduced by 0.3- and 0.2-fold, respectively, in the Fx-biscuit group. Our results suggested that Fx-biscuit possesses chemopreventive potential in the colorectal cancer of AOM/DSS mice via the downregulation of HSP70.

Fucoxanthin (Fx) is a marine carotenoid with anti-inflammatory and anti-cancer properties in various animal models of carcinogenesis. However, there is currently no information on the effects of Fx in animal models of pancreatic cancer. We investigated the chemopreventive effects of Fx in C57BL/6J mice that received allogenic and orthotopic transplantations of cancer cells (KMPC44) derived from a pancreatic cancer murine model ( Ptf1a Cre/+ ; LSL - kras G12D/+ ). Using microarray, immunofluorescence, western blot, and siRNA analyses, alterations in cancer-related genes and protein expression were evaluated in pancreatic tumors of Fx-administered mice. Fx administration prevented the adenocarcinoma (ADC) development of pancreatic and parietal peritoneum tissues in a pancreatic cancer murine model, but not the incidence of ADC. Gene and protein expressions showed that the suppression of chemokine (C-C motif) ligand 21 (CCL21)/chemokine receptor 7 (CCR7) axis, its downstream of Rho A, B- and T-lymphocyte attenuator (BTLA), N-cadherin, αSMA, pFAK(Tyr 397 ), and pPaxillin(Tyr 31 ) were significantly suppressed in the pancreatic tumors of mice treated with Fx. In addition, Ccr7 knockdown significantly attenuated the growth of KMPC44 cells. These results suggest that Fx is a promising candidate for pancreatic cancer chemoprevention that mediates the suppression of the CCL21/CCR7 axis, BTLA, tumor microenvironment, epithelial mesenchymal transition, and adhesion.

Background/aim: Fucoxanthinol (FxOH) is a marine carotenoid metabolite with potent anti-cancer activity. However, little is known about the efficacy of FxOH in pancreatic cancer. In the present study, we investigated the inhibitory effect of FxOH on six types of cells cloned from N-nitrosobis(2-oxopropyl)amine (BOP)-induced hamster pancreatic cancer (HaPC) cells., Materials and Methods: FxOH action and its molecular mechanisms were investigated in HaPC cells using flow-cytometry, comprehensive gene array, and western blotting analyses., Results: FxOH (5.0 μM) significantly suppressed the growth of four out of six types of HaPC cells. Moreover, FxOH significantly suppressed cell cycle, chemokine, integrin, actin polymerization, microtubule organization and PI3K/AKT and TGF-β signals, and activated caspase-3 followed by apoptosis and anoikis induction in HaPC-5 cells., Conclusion: FxOH may have a high potential as a cancer chemopreventive agent in a hamster pancreatic carcinogenesis model., (Copyright© 2021, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Fucoxanthinol (FxOH), a predominant metabolite from fucoxanthin (Fx), can exert potential anti-cancer effects in various cancers. However, limited data are available on the effect of FxOH or Fx on pancreatic cancer. The present study investigated the effect of FxOH on a cell line derived from pancreatic cancer tissue developed in Ptf1a Cre/+ ; LSL-k-ras G12D/+ mice., Materials and Methods: Using flow-cytometric, microarrays, and western blotting analyses, alterations in FxOH-induced apoptosis-related gene expression and protein levels were evaluated in a mice pancreatic cancer cell line, KMPC44., Results: FxOH significantly arrested the cells at S phase along with suppression of many gene sets, such as cytokine- cytokine receptor interaction and cell adhesion molecule CAMS. Moreover, attenuated protein levels for cytokine receptors, adhesion, phosphatidylinositol-3 kinase/protein kinase B, and mitogen-activated protein kinase were observed., Conclusion: FxOH may prevent pancreatic cancer development in a murine cancer model., (Copyright© 2021, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Finding eigenvectors of a sequence of real images has usually been considered to require too much computation to be practical. Our spatial temporal adaptive (STA) method reduces the computational complexity of the approximate partial eigenvalue decomposition based on image encoding. Spatial temporal encoding is used to reduce storage and computation, and then, singular value decomposition (SVD) is applied. After the adaptive discrete cosine transform (DCT) encoding, blocks that are similar in consecutive images are consolidated. The computational economy of our method was verified by tests on different large sets of images. The results show that this method is 6 to 10 times faster than the traditional SVD method for several kinds of real images. The economy of this algorithm increases with increasing correlation within the image and with increasing correlation between consecutive images within a set. This algorithm is useful for pattern recognition using eigenvectors, which is a research field that has been active recently.