Search

Wild-grown edible mushrooms are important in world diets and are also efficient metal accumulators. Yunnan, Southwest China, is the main producing region, with typically high levels of geochemical metals. The environmental factors, bioaccumulation, distribution and human health risks of metals were examined in paired soil and Tricholoma matsutake (n = 54). T. matsutake grows on acidified soils (pH = 3.95–6.56), and metals show a strong heterogeneity, with Fe, Mn, Zn and Cu in the ranges of 16–201, 0.046–8.58 g kg−1, and 22.6–215, 3.7–155 mg kg−1. High soil Fe content led to great accumulation in T. matsutake (0.24–18.8 g kg−1). However, though the soil Mn content was higher than that of Zn and Cu, their concentrations in T. matsutake were comparable (21.1–487 vs. 38.7–329 and 24.9–217 mg kg−1). This suggested that T. matsutake prefers to accumulate Zn and Cu compared to Mn, and this is supported by the bioaccumulation factors (BAFs = 0.32–17.1 vs. 0.006–1.69). Fe was mainly stored in stipes, while Mn, Zn and Cu were stored in caps, and the translocation factors (TFs) were 0.58 vs. 1.28–1.94. Therefore, stipe Fe showed the highest health risk index (HRI) at 1.28–26.9, followed by cap Cu (1.01–2.33), while 98–100% of the Mn and Zn were risk-free. The higher concentration and greater risk of Fe was attributed to the significant effect of soil Fe content (R = 0.34) and soil pH (R = −0.57). This study suggested that Fe, as an essential mineral, may exert toxic effects via the consumption of T. matsutake from high geochemical background areas. [ABSTRACT FROM AUTHOR]

The field of cholecystokinin (CC K) stimulation of exocrine pancreatic secretion has experienced major changes in the recent past. This review attempts to summarize the present status of the field. CCK production in the intestinal I cells, the molecular forms of CCK produced and subsequently circulated in the blood, the presence or absence of CCK receptors on the isolated pancreatic acinar cells and the associated signaling for acinar cell secretion, and the actual circuits and sites of action for CCK regulation of exocrine pancreatic secretion in vivo are reviewed in different animal species with an emphasis on birds, rodents, and humans. Clear differences in the relative importance of neural and direct modes of CCK action on pancreatic acinar cells were identified. Rodents seem to be endowed with both modes of action, whereas in humans the neural mode may predominate. In birds, such as duck, the direct mode needs further assistance from pituitary adenylate cyclase-activating peptide/VIP receptors. However, much further work needs to be directed to the neural mode to map out all sites of CCK action and details of the full circuits, and we foresee a major revival for this field of research in the near future. [ABSTRACT FROM AUTHOR]

Pteris vittata is the first reported arsenic (As) hyperaccumulator, which is also a calcium (Ca) indicator and adapts to calcareous environment. Therefore, it is hypothesized that Ca plays a role in As accumulation but detail effects and mechanisms are unclear. Typical Ca-compounds (CaCO 3 , Ca 3 (PO 4) 2 and CaSO 4) were added to hydroponics. CaCO 3 and Ca 3 (PO 4) 2 increased pH by 0.75 and 0.31, while CaSO 4 decreased it by 0.26. Besides, CaCO 3 increased As concentration in P. vittata frond by 25.8 % from 65.4 to 82.3 mg kg–1, while Ca 3 (PO 4) 2 and CaSO 4 decreased it by 15.1–38.2 % to 40.4–55.5 mg kg–1. So the effect of CaCO 3 on soil pH, As bioavailability and As-transformation bacterial community was further examined. In pots, CaCO 3 increased soil pH by 0.57 and increased bioavailable As concentration by 6.2 μg kg–1, thereby induced 27.3–28.5 % promotion in As plant accumulation. Rhizosphere bacterial community variance can be explained by soil pH and bioavailable As changes at 49–66 %. P. vittata frond As concentration was negatively correlated with rhizosphere As-transformation bacterial diversity (arrA and arsM) (R=-0.57 and -0.66), and positively correlated with the relative abundance of Geobacter (R=0.66) and Pseudomanas (R=0.48), which mediating As mobilization and transformation. This indicated that CaCO 3 can enhance As uptake by P. vittata via increasing soil pH, As bioavailability and mediating As-transformation bacterial community in the rhizosphere. The information helps to better understand how calcareous environment-adaptation benefits P. vittata to uptake and accumulate As. This helps to strategize more efficient processes for As-contaminated soils remediation using the hyperaccumulating plants. [Display omitted] • Ca 3 (PO 4) 2 and CaSO 4 decreased but CaCO 3 increased As uptake in P. vittat a in hydroponics. • CaCO 3 increased soil pH and As bioavailability. • CaCO 3 promoted As accumulation in P. vittata in pots. • Frond As was significantly correlated with rhizosphere As-transformation bacterial diversity (arrA and arsM). [ABSTRACT FROM AUTHOR]

Tris(1,3-dichloro-2-propyl) phosphate (TDCPP), a widely used organophosphorus flame retardant, has been frequently detected in the environment including indoor dust. Long-term exposure to TDCPP-containing dust may adversely affect human skin, however, little is known about its potential cytotoxicity. In this study, human skin keratinocytes (HaCaT) were employed to study TDCPP-induced cytotoxicity and associated mechanisms. The effects of TDCPP on cell morphology, viability, apoptosis, and cycle, and the mRNA levels of apoptosis (Bcl-2 , Bax and Caspase-3) and cell cycle (cyclin D1 , CDK2 , CDK4 and CDK6) regulatory genes were investigated. The results showed that TDCPP caused a concentration-dependent decrease in cell viability after exposing to TDCPP ≥100 μg/mL for 48 h, with a median lethal concentration of 163 μg/mL (LC 50). In addition, TDCPP induced cell apoptosis and arrested cell cycle in the G0/G1 phase at 16 and 160 μg/mL by enhancing Bax and Caspase-3 expression besides inhibiting cyclin D1 , CDK2 , CDK6 and Bcl-2 expression. Our results showed that TDCPP-induced toxicity in HaCaT cells was probably through cell apoptosis and cell cycle arrest. This study provides information on the toxicity of TDCPP to human skin cells, which may help to reduce its toxicity to human skin. Unlabelled Image • Human skin is exposed to TDCPP-containing dust on a daily basis; • We examined effects of TDCPP on normal human skin keratinocytes (HaCaT); • TDCPP decreased cell viability, and induced cell cycle arrest and apoptosis; • TDCPP enhanced the expression of apoptosis related genes Bax and Caspase3 ; • TDCPP decreased the expression of cell cycle related genes cyclin D1 , CDK2 , and CDK6. [ABSTRACT FROM AUTHOR]

Nickel (Ni) is ubiquitous in the environment and evidence has suggested that Ni can cause ocular surface inflammation, especially in fine particulate matter and personal products. Continuous daily exposure to Ni-containing dust may adversely impact the human cornea, whereas the underlying mechanism of this phenomenon remains not fully understood. Here, human corneal epithelial cells (HCEC) were employed to analyze the toxicity of Ni via detections of cell morphology, cell viability, reactive oxygen species production, cell apoptosis rate, and apoptotic gene expression levels after exposure for 24 h to uncover the damage of Ni to the cornea. A concentration-dependent inhibition of HCECs' viability and growth was observed. In particular, Ni at 100 μM significantly decreased cell viability to 76%, and many cells displayed an abnormal shape and even induced oxidative damage of HCEC by increasing ROS to 1.2 times, and further led to higher apoptosis (24%), evidenced by up-regulation of apoptotic genes Caspase-8, Caspase-9, NF-κB, IL-1β, and Caspase-3, posing a risk of dry eye. Our study suggested that Ni induces apoptosis of HCEC through oxidative damage. Therefore, Ni pollution should be comprehensively considered in health risks or toxic effects on the ocular surface. [ABSTRACT FROM AUTHOR]

Indoor dust often contains organic contaminants, which adversely impacts human health. In this study, the organic contaminants in the indoor dust from commercial offices and residential houses in Nanjing, China were extracted and their effects on human breast cancer cells (MCF-7) were investigated. Both dust extracts promoted proliferation of MCF-7 cells at ≤24 μg/100 μL, with cell viability being decreased with increasing dust concentrations. Based on LC 50 , house dust was less toxic than office dust. At 8 μg/100 μL, both extracts caused more MCF-7 cells into active cycling (G2/M + S) and increased intracellular Ca2+ influx, with house dust inducing stronger effects than office dust. Further, the expression of estrogen-responsive genes for TFF1 and EGR3 was enhanced by 3-9 and 4-9 folds, while the expression of cell cycle regulatory genes for cyclin D was enhanced by 2-5 folds. The results suggested that organic dust extract influenced cell viability, altered cell cycle, increased intracellular Ca2+ levels, and activated cell cycle regulatory and estrogen-responsive gene expressions, with house dust showing lower cytotoxicity but higher estrogenic potential on MCF-7 cells. The results indicate the importance of reducing organic contaminants in indoor dust to mitigate their adverse impacts on human health. Unlabelled Image • Effects of organic dust extract on human breast cancer cells (MCF-7) were examined. • Both extracts stimulated proliferation of MCF-7 cells at ≤24 μg/100 μL. • Extracts reduced cell viability, altered cell cycle and enhanced intracellular Ca2+. • Extracts increased expression of estrogen-responsive & cell cycle regulatory genes. • House dust induced lower toxicity but higher estrogenic potential on MCF-7 cells. [ABSTRACT FROM AUTHOR]

Arsenic (As) is a carcinogen and it is ubiquitous in the environment. Its accumulation in plants can enter the food chain, thereby causing adverse impacts on human health. Based on studies using Xenopus oocytes, engineered microbes, and model plants, aquaporins play key roles in arsenite (AsIII) passage across the cell membrane. Herein, we summarized the roles of aquaporins in AsIII uptake, transport, and accumulation. The coupling action between polar-localized aquaporins and positive transporters probably explains the efficient As transport mediated by bi-directional channels. The expression of aquaporins is regulated at both transcriptional and post-transcriptional levels via microRNAs. However, in response to As, the proteins can be modified through phosphorylation and be degraded via the ubiquitin 26S proteasome system. Further, a proposed model comprising reactive oxygen species, Ca, Ca-dependent kinases, and transcriptional factors is constructed to reveal the signaling pathways and aquaporins' responses to As in model plants. We also provided strategies to identify and investigate putative aquaporins in plants. Identification and modification of aquaporins' residues critical for their substrate selectivity, and optimization of their expression pattern by employing appropriate promoters can be employed to reduce As accumulation in crops. Based on the characteristics of their functions and expression patterns, it is promising to employ aquaporins for genetic-engineering of crops to reduce As content and increase food safety. [ABSTRACT FROM AUTHOR]

Tris(2-chloroisopropyl) phosphate (TCPP) and Tris(2-chloroethyl) phosphate (TCEP) are the widely used organophosphorus flame retardants indoors and easily accessible to the eyes as the common adhesive components of dust and particle matter, however, hardly any evidence has demonstrated their corneal toxicity. In this study, the adverse effects of TCPP, TCEP, and TCPP + TCEP exposure on human corneal epithelial cells (HCECs) were investigated. The cell viability and morphology, intracellular reactive oxygen species (ROS), cell cycle, and the expressions of cell cycle and pyroptosis-related genes were assessed to explain the underlying mechanisms. Compared to individual exposure, co-exposure to TCPP 20 +TCEP 20 showed higher cytotoxicity with a sharp decrease of >30% in viability and more serious oxidative damage by increasing ROS production to 110.92% compared to the control group. Furthermore, the cell cycle arrested at the S phase (36.20%) was observed after combined treatment, evidenced by the upregulation of cyclin D1 , CDK2 , CDK4 , CDK6 , p21, and p27. Interestingly, pyroptosis-related genes GSDMD , Caspase-1 , NLRP3 , IL-1β , IL-18 , NLRP1, and NLRC4 expressions were promoted with cell swelling and glowing morphology. Oxidative stress and cell cycle arrest probably acted as a key role in TCPP 20 +TCEP 20 -induced cytotoxicity and pyroptosis in HCECs. Our results suggested that TCPP 20 +TCEP 20 co-exposure induced severer corneal damage, further illustrating its significance in estimating indoor health hazards to humans. [Display omitted] • Effects of TCPP and TCEP on human corneal epithelial cells were originally investigated. • The corneal cytotoxicity of co-exposure to TCPP and TCEP was higher than individual exposure. • TCPP + TCEP posed a potential risk of inducing cell cycle arrest and pyroptosis via oxidate damage. • TCPP + TCEP enhanced the expressions of NLRP1 , NLRC4 , NLRP3 , Caspase-1 , IL-1β , IL-18 and GSDMD. [ABSTRACT FROM AUTHOR]