36 research outputs found
Translocation and metabolism of tricresyl phosphate in rice and microbiome system: Isomer-specific processes and overlooked metabolites.
Tricresyl phosphate (TCP) is extensively used organophosphorus flame retardants and plasticizers that posed risks to organisms and human beings. In this study, the translocation and biotransformation behavior of isomers tri-p-cresyl phosphate (TpCP), tri-m-cresyl phosphate (TmCP), and tri-o-cresyl phosphate (ToCP) in rice and rhizosphere microbiome was explored by hydroponic exposure. TpCP and TmCP were found more liable to be translocated acropetally, compared with ToCP, although they have same molecular weight and similar Kow. Rhizosphere microbiome named microbial consortium GY could reduce the uptake of TpCP, TmCP, and ToCP in rice tissues, and promote rice growth. New metabolites were successfully identified in rice and microbiome, including hydrolysis, hydroxylated, methylated, demethylated, methoxylated, and glucuronide- products. The methylation, demethylation, methoxylation, and glycosylation pathways of TCP isomers were observed for the first time in organisms. What is more important is that the demethylation of TCPs could be an important and overlooked source of triphenyl phosphate (TPHP), which broke the traditional understanding of the only man- made source of toxic TPHP in the environment. Active members of the microbial consortium GY during degradation were revealed and metagenomic analysis indicated that most of active populations contained TCP- degrading genes. It is noteworthy that the strains and function genes in microbial consortium GY that responsible for TCP isomers’ transformation were different. These results can improve our understanding of the translocation and transformation of organic pollutant isomers in plants and rhizosphere microbiome
Dexmedetomidine provides renoprotection against ischemia-reperfusion injury in mice
Abstract Introduction Acute kidney injury following surgery incurs significant mortality with no proven preventative therapy. We investigated whether the α2 adrenoceptor agonist dexmedetomidine (Dex) provides protection against ischemia-reperfusion induced kidney injury in vitro and in vivo. Methods In vitro, a stabilised cell line of human kidney proximal tubular cells (HK2) was exposed to culture medium deprived of oxygen and glucose. Dex decreased HK2 cell death in a dose-dependent manner, an effect attenuated by the α2 adrenoceptor antagonist atipamezole, and likely transduced by phosphatidylinositol 3-kinase (PI3K-Akt) signaling. In vivo C57BL/6J mice received Dex (25 μg/kg, intraperitoneal (i.p.)) 30 minutes before or after either bilateral renal pedicle clamping for 25 minutes or right renal pedicle clamping for 40 minutes and left nephrectomy. Results Pre- or post-treatment with Dex provided cytoprotection, improved tubular architecture and function following renal ischemia. Consistent with this cytoprotection, dexmedetomidine reduced plasma high-mobility group protein B1 (HMGB-1) elevation when given prior to or after kidney ischemia-reperfusion; pretreatment also decreased toll-like receptor 4 (TLR4) expression in tubular cells. Dex treatment provided long-term functional renoprotection, and even increased survival following nephrectomy. Conclusions Our data suggest that Dex likely activates cell survival signal pAKT via α2 adrenoceptors to reduce cell death and HMGB1 release and subsequently inhibits TLR4 signaling to provide reno-protection
Transcriptional regulation of macrophages in heart failure
Adverse cardiac remodeling after acute myocardial infarction is the most important pathological mechanism of heart failure and remains a major problem in clinical practice. Cardiac macrophages, derived from tissue resident macrophages and circulating monocyte, undergo significant phenotypic and functional changes following cardiac injury and play crucial roles in inflammatory response and tissue repair response. Currently, numerous studies indicate that epigenetic regulatory factors and transcription factors can regulate the transcription of inflammatory and reparative genes and timely conversion of inflammatory macrophages into reparative macrophages and then alleviate cardiac remodeling. Accordingly, targeting transcriptional regulation of macrophages may be a promising option for heart failure treatment. In this review, we not only summarize the origin and function of cardiac macrophages, but more importantly, describe the transcriptional regulation of macrophages in heart failure, aiming to provide a potential therapeutic target for heart failure
Macrophage Polarization, Metabolic Reprogramming, and Inflammatory Effects in Ischemic Heart Disease
Macrophages are highly plastic cells, and the polarization-activating actions that represent their functional focus are closely related to metabolic reprogramming. The metabolic reprogramming of macrophages manifests itself as a bias toward energy utilization, transforming their inflammatory phenotype by changing how they use energy. Metabolic reprogramming effects crosstalk with the biological processes of inflammatory action and are key to the inflammatory function of macrophages. In ischemic heart disease, phenotypic polarization and metabolic shifts in circulating recruitment and tissue-resident macrophages can influence the balance of inflammatory effects in the heart and determine disease regression and prognosis. In this review, we present the intrinsic link between macrophage polarization and metabolic reprogramming, discussing the factors that regulate macrophages in the inflammatory effects of ischemic heart disease. Our aim is to estabilsh reliable regulatory pathways that will allow us to better target the macrophage metabolic reprogramming process and improve the symptoms of ischemic heart disease
Organophosphate Pesticides and Pyrethroids in Farmland of the Pearl River Delta, China: Regional Residue, Distributions and Risks
A regional-scale survey was conducted to assess the occurrence, distribution, and risk of two extensively used pesticides (organophosphate pesticides and pyrethroids) in agricultural soils from the Pearl River Delta (PRD), South China. All target organophosphate pesticides (OPPs) and pyrethroids (PYs) were detected in the soil samples and both with a detection rate of 100%. The residues of the sum of six OPPs and the sum of four PYs were in the range of LOD–991 ng/g and 8.76–2810 ng/g, respectively. Dimethoate was the dominant OPPs, and fenpropathrin was the predominant PYs in the soils of the PRD region. With intensive agricultural activities, higher residues of OPPs and PYs in soils were detected closer to the seaside, among which Zhuhai city and Huizhou city suffered more serious combined pesticide pollution. The vertical compositional profiles showed that dimethoate could be detected through each soil layer in the PRD region’s nine cities. The human exposure estimation of OPPs showed insignificant risks to the local population. In contrast, cypermethrin and fenpropathrin showed a potential ecological risk of 2.5% and 3.75% of the sampling sites, respectively. These results can facilitate those commonly used pesticide controls and promote sustainable soil management
Research Note: Relationships between texture and water property measurements in raw intact broiler breast fillets with the wooden breast condition
ABSTRACT: Relationships between texture measurements and meat water properties were investigated in raw intact broiler breast fillets with the wooden breast (WB) condition. Texture measurements included subjective WB scores and blunt Meullenet-Owens Razor Shear (BMORS). Water properties were determined with low-field nuclear magnetic resonance (LF-NMR). Spearman correlation was used to estimate relationships between WB scores and water properties, while Pearson correlation was used for relationships between BMORS force and water properties. LF-NMR measurements exhibited 3 water components: protein-associated or hydration water T2b, intra-myofibrillar water or immobilized water T21, and extra-myofibrillar water or free water T22 in chicken breast meat. Significant and strong Spearman correlations were found between the WB scores and T21 time constant, the abundance (normalized areas) of T22, and the proportion of T21 and T22 (rs > 0.60, P < 0.001). Strong Pearson correlations (r = 0.72) were noted only between the T21 time constant and BMORS force. These results demonstrate that water may contribute to the specific texture characteristics measured with subjective WB scoring (palpable hardness and rigidity) and BMORS (hardness and share force) in raw broiler breast fillets with the WB condition
Geochemical Contamination, Speciation, and Bioaccessibility of Trace Metals in Road Dust of a Megacity (Guangzhou) in Southern China: Implications for Human Health
Road dust has been severely contaminated by trace metals and has become a major health risk to urban residents. However, there is a lack of information on bioaccessible trace metals in road dust, which is necessary for an accurate health risk assessment. In this study, we collected road dust samples from industrial areas, traffic intersections, and agricultural fields from a megacity (Guangzhou), China, and conducted a geochemical enrichment, speciation, and bioaccessibility-based health risk assessment of trace metals. In comparison with local soil background values, the results revealed a significant accumulation of trace metals, including Zn, Cd, Cu, and Pb in the road dust, which is considered moderate to heavy pollution. Sequential extraction indicated that most trace metals in the road dust were primarily composed of a Fe/Mn oxide-bound fraction, carbonate-bound fraction, and residual fraction, while the dominant fraction was the organic matter-bound fraction of Cu, and the residual fractions of As, Cr, and Ni. The in vitro gastrointestinal (IVG) method revealed that high percentages of Zn, Cd, Cu, and As were bioaccessible, suggesting the possible dissolution of trace metals from adsorbed and carbonate-associated fractions in road dust exposed to the biological fluid matrix. The IVG bioaccessibility-based concentration largely decreased the noncarcinogenic health risk to a negligible level. Nevertheless, the entire population is still exposed to the cumulative probability of a carcinogenic risk, which is primarily contributed to by As, Cd, Cr, and Pb. Future identification of the exact sources of these toxic metals would be helpful for the appropriate management of urban road dust contamination
Levels, Distribution and Health Risk Assessment of Organochlorine Pesticides in Agricultural Soils from the Pearl River Delta of China
To reveal the pollution status of agricultural soils along with rapid urbanization and economic growth, a large regional survey of organochlorine pesticides (OCPs) in agricultural soils was conducted in the Pearl River Delta (PRD) of China. The results showed that the total residues of 23 OCPs were in the range of ND-946 ng/g dry weight. OCP residues showed distinct spatial distribution characteristics within the PRD. OCPs were mainly found in areas with high agricultural production and industrial activities. Higher OCP concentrations were observed in the top layer of soil, while the concentration decreases to marginal levels when the soil depth is greater than 50 cm. OCPs are mainly derived from historical use. Hexachlorocyclohexanes (HCHs) in the top soil of the study area are mainly from the use of lindane. Soil pH was negatively and significantly correlated with total OCP concentration. The human health risk assessment showed no health risk for children, while for adults, there is a non-carcinogenic risk, which needs to be noticed. Agricultural activities and industrial production have made the region a pollution hotspot and should arouse more stringent regulation to protect the environment and food safety
Polycyclic Aromatic Hydrocarbons Pollution Characteristics in Agricultural Soils of the Pearl River Delta Region, China
In order to investigate the pollution status of polycyclic aromatic hydrocarbons (PAHs) in the agricultural soil, 240 agricultural soil topsoil samples were collected from nine Pearl River Delta cities from June to September 2019. In addition, 72 samples were collected for vertical soil profiles, which soil profiles were excavated to a depth of 80 cm. After sample preparation, GC-MS was used for the separation of compounds on a HP-5MS quartz capillary column. ArcGIS software was used to map the spatial distribution. Health risk assessment was conducted using USEPA standard. The results showed that the total concentration of 16 PAHs ranged from 43.4 to 5630 ng/g, with an average of 219 ng/g. The spatial distribution showed that most of the seriously polluted areas were in the coastal area, near the port, and there was point source pollution in the Gaoming of Foshan. Vertically distributed display Zhuhai, Jiangmen, Zhaoqing, Shenzhen and Dongguan increased and then decreased from bottom to bottom, showing a low-high-low pattern, the concentration of PAHs in Zhongshan and Foshan decreased with the soil depth, while the concentration of PAHs in Guangzhou and Huizhou was enriched with human activities. The PAHs components in soil samples were mainly medium and high rings (4–6 rings). The analysis of the origin of PAH in soil samples showed that the mixture of incomplete combustion sources of fossil fuels such as coal and biomass and traffic emission sources were the main sources of soil PAHs. A small amount can be attributed to oil sources such as oil spills. The human health risk assessment showed no cancer risk for children, while for adults, may cause a potential risk of cancer, which needs to be noticed. Spearman correlation analysis showed that PAH content was significantly correlated with SOC (p < 0.01) and pH (p < 0.05). Port transport, road emissions and industrial production make the area a pollution hot topic, and supervision should be strengthened to protect the environment and food safety