Explore the vast range of titles available.

Diet-related obesity is associated with increased intestinal hyperpermeability. High dietary fat intake causes an increase in colonic bile acids (BAs), particularly deoxycholic acid (DCA). We hypothesize that DCA modulates the gene expression of multiple cell junction pathways and increases intestinal permeability. With a human Caco-2 cell intestinal model, we used cell proliferation, PCR array, biochemical, and immunofluorescent assays to examine the impact of DCA on the integrity of the intestinal barrier and gene expression. The Caco-2 cells were grown in monolayers and challenged with DCA at physiological, sub-mM, concentrations. DCA increased transcellular and paracellular permeability (>20%). Similarly, DCA increased intracellular reactive oxidative species production (>100%) and accompanied a decrease (>40%) in extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathways. Moreover, the mRNA levels of 23 genes related to the epithelial barrier (tight junction, focal adhesion, gap junction, and adherens junction pathways) were decreased (>40%) in (0.25 mM) DCA-treated Caco-2 cells compared to untreated cells. Finally, we demonstrated that DCA decreased (>58%) the protein content of occludin present at the cellular tight junctions and the nucleus of epithelial cells. Collectively, DCA decreases the gene expression of multiple pathways related to cell junctions and increases permeability in a human intestinal barrier model.

Diosgenin, a steroidal saponin obtained from fenugreek (Trigonella foenum graecum), was found to exert anti-carcinogenic properties, such as inhibiting proliferation and inducing apoptosis in a variety of tumor cells. However, the effect of diosgenin on cancer metastasis remains unclear. The aim of the study is to examine the effect of diosgenin on migration and invasion in human prostate cancer PC-3 cells. Diosgenin inhibited proliferation of PC-3 cells in a dose-dependent manner. When treated with non-toxic doses of diosgenin, cell migration and invasion were markedly suppressed by in vitro wound healing assay and Boyden chamber invasion assay, respectively. Furthermore, diosgenin reduced the activities of matrix metalloproteinase-2 (MMP-2) and MMP-9 by gelatin zymography assay. The mRNA level of MMP-2, -9, -7 and extracellular inducer of matrix metalloproteinase (EMMPRIN) were also suppressed while tissue inhibitor of metalloproteinase-2 (TIMP-2) was increased by diosgenin. In addition, diosgenin abolished the expression of vascular endothelial growth factor (VEGF) in PC-3 cells and tube formation of endothelial cells. Our immunoblotting assays indicated that diosgenin potently suppressed the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt, extracellular signal regulating kinase (ERK) and c-Jun N-terminal kinase (JNK). In addition, diosgenin significantly decreased the nuclear level of nuclear factor kappa B (NF-κB), suggesting that diosgenin inhibited NF-κB activity. The results suggested that diosgenin inhibited migration and invasion of PC-3 cells by reducing MMPs expression. It also inhibited ERK, JNK and PI3K/Akt signaling pathways as well as NF-κB activity. These findings reveal new therapeutic potential for diosgenin in anti-metastatic therapy.

Background/Objectives: Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, exhibits anti-inflammatory effects and attenuates the process of colon carcinogenesis. Certain healthy diets increase colonic UDCA concentrations, but its anticancer mechanistic actions remain largely unknown. We hypothesize that UDCA preferentially inhibits cancerous colon cell proliferation with a minimal effect on noncancerous colon cells. Methods: With human noncancerous NCM460 colon cell and cancerous HCT116 colon cell culture models, we performed biochemical, western blotting, PCR array, cell cycle, apoptosis, and immunofluorescent assays to determine the effects of UDCA treatment on colon cell proliferation and the underlying molecular mechanisms. Results: The inhibitory potential of UDCA against cell proliferation (via cell cycle arrest and apoptosis) was 90% greater in cancerous HCT116 cells than noncancerous NCM460 cells when treated with UDCA (0 to 0.4 mM) for 48 h. In UDCA-treated HCT116 cells, we identified 18 genes with ≥80% change (compared to untreated cells) in mRNA levels out of 93 apoptotic genes which were involved in caspase, death receptor, and NFκB pathways. At the molecular level, 0.4 mM UDCA reduced the protein level of the proto-oncogenic c-Myc gene but increased the putative tumor suppressor p21 gene (≥100%) via the ERK1/2/c-Myc/p21 pathway, which regulates cell cycle and apoptosis. These data are consistent with lower c-Myc but higher p21 expression in normal colon tissues compared to cancerous colon tissues. Conclusions: Collectively, UDCA inhibits cancerous HCT116 colon cells to a higher degree than in noncancerous NCM460 colon cells through cell cycle and apoptosis involving ERK1/2/c-Myc/p21 signaling.

A growing body of evidence suggests that food insecurity is associated with adverse mental health outcomes such as depression and anxiety. In this study, the relationship between food insecurity and depression was examined using data from the 2005–2016 National Health and Nutrition Examination Survey (NHANES). Food insecurity was assessed with the 18-item United States Food Security Survey Module with zero affirmative responses indicating high food security, 1 or 2 affirmative responses indicating marginal food security, and ≥3 affirmative responses indicating food insecurity. Depression was assessed with the Patient Health Questionnaire-9 with scores ≥10 indicating depression. Data were analyzed from 28,448 adult participants aged 20 or older. Food insecurity was present in 19.2% of the sample population (n = 5452). Food security status was significantly associated with gender, race, education level, marital status, smoking status, and BMI (Rao-Scott chi-square, p < 0.05). Fully food secure and very low food security adults experienced depression at a rate of 5.1% and 25.8%, respectively (Rao-Scott chi-square, p < 0.0001). Participants with very low food security had a significantly greater odds of depression than food secure adults, OR = 3.50 (95% CI: 2.98, 4.12). These findings suggest that food insecurity is a significant risk factors for depression in US adults over 20 years of age. To address this issue in our citizenry, police initiatives and public health interventions addressing both food access and mental health should be prioritized.

Targeting ferritin via autophagy (ferritinophagy) to induce ferroptosis, an iron- and reactive oxygen species (ROS)-dependent cell death, provides novel strategies for cancer therapy. Using a ferroptosis-specific inhibitor and iron chelator, the vulnerability of triple-negative breast cancer (TNBC) MDA-MB-231 cells to ferroptosis was identified and compared to that of luminal A MCF-7 cells. Saponin formosanin C (FC) was revealed as a potent ferroptosis inducer characterized by superior induction in cytosolic and lipid ROS formation as well as GPX4 depletion in MDA-MB-231 cells. The FC-induced ferroptosis was paralleled by downregulation of ferroportin and xCT expressions. Immunoprecipitation and electron microscopy demonstrated the involvement of ferritinophagy in FC-treated MDA-MB-231 cells. The association of FC with ferroptosis was strengthened by the results that observed an enriched pathway with differentially expressed genes from FC-treated cells. FC sensitized cisplatin-induced ferroptosis in MDA-MB-231 cells. Through integrated analysis of differentially expressed genes and pathways using the METABRIC patients’ database, we confirmed that autophagy and ferroptosis were discrepant between TNBC and luminal A and that TNBC was hypersensitive to ferroptosis. Our data suggest a therapeutic strategy by ferroptosis against TNBC, an aggressive subtype with a poor prognosis.

ABSTRACT Previous studies have shown that dietary selenium (Se) deficiency in mice reshapes gut microbiota, exacerbates healthspan deterioration (e.g., type 2 diabetes), and paradoxically activates beneficial longevity pathways. This study demonstrated that dietary Se deficiency accelerated many age‐related gut microbial changes in aged telomere‐humanized C57BL/6J diabetic mice in a sexually dimorphic manner, with Akkermansia muciniphila showing the greatest enrichment in males. However, dietary Se deficiency did not enrich A. muciniphila in mature or middle‐aged male C57BL/6J wild‐type mice. Oral gavage of A. muciniphila alleviated Se deficiency‐induced type 2 diabetes‐like symptoms, reversed mucosal barrier dysfunction and gut inflammation, and resulted in a trend of symbiotic and competitive suppression changes in certain gut bacteria in mature wild‐type mice under conventional conditions. The beneficial effects of A. muciniphila appeared to be independent of selenoproteins sensitive to dietary Se deficiency, such as GPX1, SELENOH, and SELENOW, in the liver and muscle. Altogether, these results show that dietary Se deficiency accelerates age‐related A. muciniphila enrichment specifically in aged male mice with severe insulin resistance and pancreatic senescence, indicating a potential hormetic response to Se deficiency through reshaped gut microbiota, which alleviates hyperglycemia and partially compensates for healthspan decline. Gut Akkermansia muciniphila is enriched by dietary selenium deficiency in aged telomere‐humanized mice and counteracts dietary selenium deficiency‐induced type 2 diabetes.

Effects on type 2 diabetes risk among non-deficient subjects have been mixed; no effects were observed among adult subjects of the Selenium and Vitamin E Cancer Prevention Trial (SELECT)(4) and among younger adult subjects of the Selenium Trial with selenised yeast(5), but there was an increased risk among older adults in both the Selenium Trial(5) and the Nutritional Prevention of Cancer (NPC) trial(6). On the basis of changes in several metabolic and cardiovascular parameters (e.g. decreased insulin, LDL-cholesterol and C-reactive protein concentrations; increased HDL-cholesterol, total antioxidant capacity and glutathione concentrations), the authors concluded that Se supplementation benefited the treatment group, suggesting a protective role of Se supplementation in alleviation of the metabolic syndrome in patients with congestive heart failure. [...]at adequate and greater intakes, Se is increasingly incorporated non-specifically into all proteins by replacement of methionine with selenomethionine residues(16). [...]as we have pointed out, this question must be addressed in reference not only to health status but also to subject Se status, as both can affect the metabolic utilisation of this essential nutrient. [...]trials must be careful to characterise subject baseline Se status, as well as the specific identity of the intervention and control agents.

Butyrate, an intestinal microbiota metabolite of dietary fiber, exhibits chemoprevention effects on colon cancer development. However, the mechanistic action of butyrate remains to be determined. We hypothesize that butyrate inhibits cancerous cell proliferation but to a lesser extent in noncancerous cells through regulating apoptosis and cellular-signaling pathways. We tested this hypothesis by exposing cancerous HCT116 or non-cancerous NCM460 colon cells to physiologically relevant doses of butyrate. Cellular responses to butyrate were characterized by Western analysis, fluorescent microscopy, acetylation, and DNA fragmentation analyses. Butyrate inhibited cell proliferation, and led to an induction of apoptosis, genomic DNA fragmentation in HCT116 cells, but to a lesser extent in NCM460 cells. Although butyrate increased H3 histone deacetylation and p21 tumor suppressor expression in both cell types, p21 protein level was greater with intense expression around the nuclei in HCT116 cells when compared with that in NCM460 cells. Furthermore, butyrate treatment increased the phosphorylation of extracellular-regulated kinase 1/2 (p-ERK1/2), a survival signal, in NCM460 cells while it decreased p-ERK1/2 in HCT116 cells. Taken together, the activation of survival signaling in NCM460 cells and apoptotic potential in HCT116 cells may confer the increased sensitivity of cancerous colon cells to butyrate in comparison with noncancerous colon cells.

Oral squamous cell carcinoma (OSCC) is the predominant histological type of the head and neck squamous cell carcinoma (HNSCC). By comparing the differentially expressed genes (DEGs) in OSCC-TCGA patients with copy number variations (CNVs) that we identify in OSCC-OncoScan dataset, we herein identified 37 dysregulated candidate genes. Among these potential candidate genes, 26 have been previously reported as dysregulated proteins or genes in HNSCC. Among 11 novel candidates, the overall survival analysis revealed that melanotransferrin (MFI2) is the most significant prognostic molecular in OSCC-TCGA patients. Another independent Taiwanese cohort confirmed that higher MFI2 transcript levels were significantly associated with poor prognosis. Mechanistically, we found that knockdown of MFI2 reduced cell viability, migration and invasion via modulating EGF/FAK signaling in OSCC cells. Collectively, our results support a mechanistic understanding of a novel role for MFI2 in promoting cell invasiveness in OSCC.

The thioredoxin-like (Rdx) family proteins contain four selenoproteins (selenoprotein H, SELENOH; selenoprotein T, SELENOT; selenoprotein V, SELENOV; selenoprotein W, SELENOW) and a nonselenoprotein Rdx12. They share a CxxU or a CxxC (C, cysteine; x, any amino acid; U, selenocysteine) motif and a stretch of eGxFEI(V) sequence. From the evolutionary perspective, SELENOW and SELENOV are clustered together and SELENOH and SELENOT are in another branch. Selenoproteins in the Rdx family exhibit tissue- and organelle-specific distribution and are differentially influenced in response to selenium deficiency. While SELENOH is nucleus-exclusive, SELENOT resides mainly in endoplasmic reticulum and SELENOW in cytosol. SELENOV is expressed essentially only in the testes with unknown cellular localization. SELENOH and SELENOW are more sensitive than SELENOT and SELENOV to selenium deficiency. While physiological functions of the Rdx family of selenoproteins are not fully understand, results from animal models demonstrated that (1) brain-specific SELENOT knockout mice are susceptible to 1-methyl-4-phenylpyridinium-induced Parkinson’s disease in association with redox imbalance and (2) adult zebrafishes with heterozygous SELENOH knockout are prone to dimethylbenzanthracene-induced tumorigenesis together with increased DNA damage and oxidative stress. Further animal and human studies are needed to fully understand physiological roles of the Rdx family of selenoproteins in redox regulation, genome maintenance, aging, and age-related degeneration.