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1.
Food Sci Nutr ; 12(4): 2346-2363, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38628176

ABSTRACT

A safety evaluation was performed of Symbiota®, which is made by a proprietary anaerobic fermentation process of soybean with multistrains of probiotics and a yeast. The battery of genotoxicity studies showed that Symbiota® has no genotoxic effects. Safety and tolerability were further assessed by acute or repeated dose 28- and 90-day rodent studies, and no alterations in clinical observations, ophthalmological examination, blood chemistry, urinalysis, or hematology were observed between the control group and the different dosing groups (1.5, 5, and 15 mL/kg/day). There were no adverse effects on specific tissues or organs in terms of weight and histopathology. Importantly, the Symbiota® treatment did not perturb hormones and other endocrine-related endpoints. Of note, the No-Observed-Adverse-Effect-Level was determined to be 15 mL/kg/day in rats. Moreover, a randomized, double-blind, placebo-controlled clinical trial was recently conducted with healthy volunteers who consumed 8 mL/day of placebo or Symbiota® for 8 weeks. Only mild adverse events were reported in both groups, and the blood chemistry and blood cell profiles were also similar between the two groups. In summary, this study concluded that the oral consumption of Symbiota® at 8 mL/day by the general population does not pose any human health concerns.

2.
Nat Commun ; 5: 3472, 2014 Mar 25.
Article in English | MEDLINE | ID: mdl-24668028

ABSTRACT

Cancer stem cells (CSCs) are a promising target for treating cancer, yet how CSC plasticity is maintained in vivo is unclear and is difficult to study in vitro. Here we establish a sustainable primary culture of Oct3/4(+)/Nanog(+) lung CSCs fed with CD90(+) cancer-associated fibroblasts (CAFs) to further advance our knowledge of preserving stem cells in the tumour microenvironment. Using transcriptomics we identify the paracrine network by which CAFs enrich CSCs through de-differentiation and reacquisition of stem cell-like properties. Specifically, we find that IGF1R signalling activation in cancer cells in the presence of CAFs expressing IGF-II can induce Nanog expression and promote stemness. Moreover, this paracrine signalling predicts overall and relapse-free survival in stage I non-small cell lung cancer (NSCLC) patients. IGF-II/IGF1R signalling blockade inhibits Nanog expression and attenuates cancer stem cell features. Our data demonstrate that CAFs constitute a supporting niche for cancer stemness, and targeting this paracrine signalling may present a new therapeutic strategy for NSCLC.


Subject(s)
Adenocarcinoma/genetics , Carcinoma, Squamous Cell/genetics , Fibroblasts/metabolism , Lung Neoplasms/genetics , Neoplastic Stem Cells/metabolism , Paracrine Communication , Small Cell Lung Carcinoma/genetics , Adenocarcinoma/metabolism , Aged , Aged, 80 and over , Animals , Carcinoma, Squamous Cell/metabolism , Cells, Cultured , Female , Gene Expression Profiling , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Humans , Insulin-Like Growth Factor II/genetics , Insulin-Like Growth Factor II/metabolism , Lung Neoplasms/metabolism , Male , Mice , Middle Aged , Nanog Homeobox Protein , Neoplasm Transplantation , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , Receptor, IGF Type 1 , Receptors, Somatomedin/genetics , Receptors, Somatomedin/metabolism , Small Cell Lung Carcinoma/metabolism , Thy-1 Antigens/metabolism , Tumor Microenvironment
3.
J Magn Reson Imaging ; 36(5): 1179-85, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22791565

ABSTRACT

PURPOSE: To evaluate the vasodilatory response of normal human brain and meningiomas under repeated breathholding challenges using vascular space occupancy (VASO) MRI at 3 Tesla (T). MATERIALS AND METHODS: Five normal volunteers and five patients with meningiomas were recruited for this study. For the normal group, VASO MRI during repeated breathholds of different duration (5 to 30 s) was acquired. Patients performed a 15-s breathhold paradigm for VASO MRI. The maximum signal change and full-width at half-maximum (FWHM) were determined by curve fitting. RESULTS: Significant VASO signal decreases in the gray matter could be detected for a breathhold period as short as 5 s. The fractional activation volume vs. breathhold duration reached a plateau around 34.21 ± 3.39% at 15 s. In the patient group, there were significant VASO signal decreases in normal gray matters and also in small areas of three large-sized meningiomas. CONCLUSION: The 3T VASO MRI detected significant signal decreases in the gray matter, but not in the white matter, during short periods of breathholding. The fractional activation volume reached the plateau at 15-s breathhold, which is recommended for clinical application.


Subject(s)
Brain Neoplasms/pathology , Breath Holding , Cerebral Arteries/pathology , Image Enhancement/methods , Meningeal Neoplasms/pathology , Meningioma/pathology , Adult , Aged , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity , Young Adult
4.
Acta Radiol ; 53(2): 192-6, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22184677

ABSTRACT

BACKGROUND: In the Taiwanese military, flatfoot is indicated by a calcaneal-fifth metatarsal angle (arch angle) ≥165°. However, the arch angle is not always easily defined. PURPOSE: To assess correlations between the arch angle and other radiographic measures and thus identify an alternative radiographic measure for diagnosing flatfoot. MATERIAL AND METHODS: Eighty-seven male Taiwanese military recruits were studied (median age 22 years, interquartile range 20-23 years). Lateral, weight-bearing radiographs were taken. Five radiographic measurements, including the calcaneal-fifth metatarsal angle (arch angle), medial arch angle (MAA), calcaneal pitch angle (CP), talus angle (TA), and talar-first metatarsal angle (TFM) were made. Correlations between the arch angle and all other measures were determined. A cut-off value for predicting flatfoot (arch angle ≥165°) was determined for each measure using the Youden index and receiver-operating characteristic (ROC) curves were generated for each measure to assess diagnostic accuracy. RESULTS: All measures were significantly correlated with arch angle (P < 0.05); however, the strongest correlation was for CP (ρ = -0.905, P < 0.001). CP was associated with the highest area under the ROC (0.988 vs. 0.711-0.912 for the other measures). Further, CP (cut-off <12.3°) had the highest sensitivity (92.0%), positive predictive value (76.7%), and negative predictive value (96.5%). TFM (>9.5°) had the highest specificity (90.3% vs. 88.75 for CP <12.3°). CONCLUSION: CP is inversely correlated with arch angle in Taiwanese male military recruits. CP < 12.3° is a significant predictor of flatfoot. Assessment of CP may be used as an alternative means of diagnosing flatfoot when the arch angle is not easily defined.


Subject(s)
Flatfoot/diagnostic imaging , Adult , Calcaneus/diagnostic imaging , Foot/diagnostic imaging , Humans , Male , Metatarsal Bones/diagnostic imaging , Predictive Value of Tests , ROC Curve , Radiography , Sensitivity and Specificity , Taiwan , Talus , Young Adult
5.
Toxicol Lett ; 192(2): 252-60, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-19896525

ABSTRACT

1,10-phenanthroline (phen), flufenamic acid, and indomethacin are inhibitors of aldo-keto reductases 1C1 (AKR1C1), but only phen decreased the benzo[a]pyrene (BaP)-induced cytochrome P450 1a1 (Cyp1a1) protein level. Therefore the decrease in the BaP-induced Cyp1a1 protein level was not due to inhibition of Akr1c1, but to phen itself. Phen decreased the BaP-induced Cyp1a1 promoter activity and protein expression, and in contrast, it increased Cyp1a1 mRNA, resulting from an increase in mRNA stability. Phen is also known as a transition metal ion-chelator. Along with the phen study, we also found that Zn(2+), Fe(2+) and Cu(2+) increased Cyp1a1 mRNA and protein stability. Our results show that phen stabilized the mRNA of Cyp1a1, although it decreased cell viability. In addition, Zn(2+) and Fe(2+) highly neutralized phen's suppression of Cyp1a1 protein expression, but they only slightly neutralized phen's promotion of mRNA stability and suppression of cell viability, and had no effect on phen's suppression of promoter activity. Phen's effect on Cyp1a1 expression was reversible, which indicates that phen is non-covalently linked to its target. This report elucidates a new role for phen of stabilizing Cyp1a1 mRNA, and provides information for further studies on mRNA stabilization.


Subject(s)
Cytochrome P-450 CYP1A1/genetics , Phenanthrolines/pharmacology , RNA Stability/drug effects , RNA, Messenger/metabolism , Xenobiotics/pharmacology , Benzo(a)pyrene/pharmacology , Cations, Divalent/pharmacology , Cell Survival/drug effects , Copper/pharmacology , Cytochrome P-450 CYP1A1/metabolism , Gene Expression Regulation, Enzymologic/drug effects , Iron/pharmacology , Transcription, Genetic/drug effects , Zinc/pharmacology
6.
Chem Res Toxicol ; 22(12): 1938-47, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19961161

ABSTRACT

Cytochrome P450 1a1 (Cyp1a1) is a phase I xenobiotic-metabolizing enzyme, the expression of which is mainly driven by the aryl hydrocarbon receptor (AhR). Cyp1a1 messenger (m)RNA is labile. Our study indicates that 1-nitropyrene (1-NP) highly induced Cyp1a1 protein expression, although its induction of AhR transactivation activity was negligible. The fact that the nuclear receptors, CAR, FXR LXR, or PXR, did not induce Cyp1a1 expression indicates that they do not mediate 1-NP's action. When the AhR transcript was degraded by small hairpin (sh)RNA-AhR, 1-NP-induced Cyp1a1 expression largely decreased. In addition, 1-NP did not induce Cyp1a1 in AhR pathway-deficient mutant cells, which indicates that the AhR is essential for 1-NP's action. When Cyp1a1's turnover was examined, 1-NP was able to stabilize the 1-NP- and benzo[a]pyrene (BaP)-induced Cyp1a1 mRNA, but not protein. 1-NP-induced Cyp1a1 mRNA stabilization was mediated by Akt, but not by p38 MAPK, MEK1/2, or JNK. Among aryl hydrocarbons with four annealed phenyl rings, including pyrene, 1-NP, fluoranthene, 3-nitrofluoranthene, chrysene, and 6-nitrochrysene, only 1-NP was able to stabilize Cyp1a1 mRNA. 1-NP's action was gene specific. In conclusion, stabilizing Cyp1a1 mRNA greatly contributed to 1-NP-induced Cyp1a1 expression, which provides new insight into gene regulation by the AhR ligand and mRNA stabilization.


Subject(s)
Cytochrome P-450 CYP1A1/metabolism , Mutagens/toxicity , Proto-Oncogene Proteins c-akt/metabolism , Pyrenes/toxicity , RNA, Messenger/metabolism , Animals , Benzo(a)pyrene/chemistry , Benzo(a)pyrene/pharmacology , Cell Line, Tumor , Cytochrome P-450 CYP1A1/genetics , Mice , Mutagens/chemistry , Pyrenes/chemistry , RNA Interference , RNA Stability , Receptors, Aryl Hydrocarbon/genetics , Receptors, Aryl Hydrocarbon/metabolism
7.
Toxicology ; 244(2-3): 257-70, 2008 Feb 28.
Article in English | MEDLINE | ID: mdl-18207300

ABSTRACT

It is reported that diesel exhaust particles contain more 1-nitropyrene (1-NP) than benzo[a]pyrene (B[a]P), both of which are potent carcinogenic compounds. In this study, we show that 1-NP is more potent in reducing cell viability than B[a]P, pyrene, nitrobenzene, and nitromethane. Aldo-keto reductases (AKRs) are enzymes which metabolize polycyclic aromatic hydrocarbons into active metabolites that form PAH-DNA-adducts causing mutagenesis of DNA. We found that the AKR1C2 inhibitor, ursodeoxycholic acid (UA), inhibited 1-NP-induced, but not B[a]P-induced, phosphorylation of p53 and cleavage of poly (ADP-ribose) polymerase (PARP). 1-NP-induced apoptosis was also suppressed by UA, as detected by Hoechst 33342 staining, flow cytometric analysis of subG0/G1 phase and annexin V binding to phosphatidylserine. The AKR1C1 and 1C4 inhibitor, 1,10-phenanthroline (Phen), inhibited the toxic effects of both 1-NP and B[a]P. In contrast, the AKR7A1 and 7A5 inhibitors, succinate and citrate, did not influence the toxic effects of 1-NP or B[a]P. In addition, several metabolic and signaling pathways were analyzed, these were used to compare the results of the toxic effect of AKRs on 1-NP and B[a]P. Through the application of kinase inhibitors, results indicated that p38-MAPK, but not ERK1/2 or JNK, was essential for mediating both 1-NP's and B[a]P's induction of the phosphorylation of p53 and cleavage of PARP. Neither ellipticine, a CYP1A1 inhibitor, nor 2,6-diisopropylphenol, a CYP1A2 and 2B1 inhibitor, blocked the toxic effects of 1-NP and B[a]P, which indicates that neither CYP1A1, 1A2, nor 2B1 is essential for the transformation of 1-NP and B[a], into toxic metabolites. AKR1C2 was constitutively expressed in HepG2 cells and was not regulated by 1-NP or B[a]P. In conclusion, this is the first report on AKRs' actions toward nitro-PAH in cells. The metabolic and signaling pathways for the toxic effects of both 1-NP and B[a]P are similar except that AKR1C2 plays differential role between them. The results provide valuable information for further investigations on AKRs.


Subject(s)
Alcohol Oxidoreductases/metabolism , Apoptosis/drug effects , Benzo(a)pyrene/toxicity , Mutagens/toxicity , Pyrenes/toxicity , Tumor Suppressor Protein p53/metabolism , Aldehyde Reductase , Aldo-Keto Reductases , Benzimidazoles , Benzo(a)pyrene/metabolism , Blotting, Western , Cell Line, Tumor , Cell Survival/drug effects , Flow Cytometry , Fluorescent Dyes , Humans , Isoenzymes/metabolism , Luciferases/metabolism , Mutagens/metabolism , Phosphorylation/drug effects , Plasmids/drug effects , Plasmids/genetics , Polycyclic Aromatic Hydrocarbons/metabolism , Pyrenes/metabolism , Signal Transduction/drug effects , Tetrazolium Salts , Thiazoles
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