Derivatization of N-Acyl Glycines by 3-Nitrophenylhydrazine for Targeted Metabolomics Analysis and Their Application to the Study of Diabetes Progression in Mice.

N-Acyl glycines (NAGlys) are an important class of metabolites in the detoxification system of the human body. They have been used in the diagnosis of several metabolic diseases. Liquid chromatography-mass spectrometry (LC-MS) is the most frequently used NAGlys detection platform. Here, we describe a simple and sensitive method of NAGlys detection by LC-MS in plasma and urine samples. This approach is based on the use of a derivatization reagent, 3-nitrophenylhydrazine. The reaction is quick in aqueous solution, and no quenching step is needed. To expand the coverage of NAGlys when standards are not available, NAGlys were first identified based on high-resolution LC-MS. Quantification was subsequently carried out on triple quadrupole LC-MS. This approach allowed a much broader measurement of NAGlys (41 NAGlys in total), especially when authentic standards are unavailable. Comprehensive analysis of NAGlys with this new method was applied in plasma and urine samples of db/db diabetic and non-diabetic db/m+ control mice. The majority of detected NAGlys were altered with high differentiation ability in plasma and urine samples from diabetic and non-diabetic mice. These identified NAGlys hold the potential to be diagnostic biomarkers for type II diabetes and diabetic complications.

Mechanistic insights into hormesis induced by erythromycin in the marine alga Thalassiosira weissflogii.

Erythromycin (ERY) is a typical macrolide antibiotic with large production and extensive use on a global scale. Detection of ERY in both freshwaters and coaster seawaters, as well as relatively high ecotoxicity of ERY have been documented. Notably, hormesis has been reported on several freshwater algae under ERY stress, where growth was promoted at relatively lower exposures but inhibited at higher treatment levels. On the contrary, there is limited information of ERY toxicity in marine algae, hampering the risk assessment on ERY in the coaster waters. The presence of hormesis may challenge the current concept of dose-response adopted in chemical risk assessment. Whether and how exposure to ERY can induce dose-dependent toxicity in marine algae remain virtually unknown, especially at environmentally relevant concentrations. The present study used a model marine diatom Thalassiosira weissflogii (T. weissflogii) to reveal its toxicological responses to ERY at different biological levels and decipher the underlying mechanisms. Assessment of multiple apical endpoints shows an evident growth promotion following ERY exposure at an environmentally relevant concentration (1 µg/L), associated with increased contents reactive oxygen species (ROS) and chlorophyll-a (Chl-a), activated signaling pathways related to ribosome biosynthesis and translation, and production of total soluble protein. By contrast, growth inhibition in the 750 and 2500 µg/L treatments was attributed to reduced viability, increased ROS formation, reduced content of total soluble protein, inhibited photosynthesis, and perturbed signaling pathways involved in xenobiotic metabolism, ribosome, metabolism of amino acid, and nitrogen metabolism. Measurements of multiple apical endpoints coupled with de novo transcriptomics analysis applied in the present study, a systems biology approach, can generate detailed mechanistic information of chemical toxicity including dose-response and species sensitivity difference used in environmental risk assessment.

Transgenerational bone toxicity in F3 medaka (Oryzias latipes) induced by ancestral benzo[a]pyrene exposure: Cellular and transcriptomic insights.

Benzo[a]pyrene (BaP), a ubiquitous pollutant, raises environmental health concerns due to induction of bone toxicity in the unexposed offspring. Exposure of F0 ancestor medaka (Oryzias latipes) to 1 µg/L BaP for 21 days causes reduced vertebral bone thickness in the unexposed F3 male offspring. To reveal the inherited modifications, osteoblast (OB) abundance and molecular signaling pathways of transgenerational BaP-induced bone thinning were assessed. Histomorphometric analysis showed a reduction in OB abundance. Analyses of the miRNA and mRNA transcriptomes revealed the dysregulation of Wnt signaling (frzb/ola-miR-1-3p, sfrp5/ola-miR-96-5p/miR-455-5p) and bone morphogenetic protein (Bmp) signaling (bmp3/ola-miR-96-5p/miR-181b-5p/miR-199a-5p/miR-205-5p/miR-455-5p). Both pathways are major indicators of impaired bone formation, while the altered Rank signaling in osteoclasts (c-fos/miR-205-5p) suggests a potentially augmented bone resorption. Interestingly, a typical BaP-responsive pathway, the Nrf2-mediated oxidative stress response (gst/ola-miR-181b-5p/miR-199a-5p/miR-205), was also affected. Moreover, mRNA levels of epigenetic modification enzymes (e.g., hdac6, hdac7, kdm5b) were found dysregulated. The findings indicated that epigenetic factors (e.g., miRNAs, histone modifications) may directly regulate the expression of genes associated with transgenerational BaP bone toxicity and warrants further studies. The identified candidate genes and miRNAs may serve as potential biomarkers for BaP-induced bone disease and as indicators of historic exposures in wild fish for conservation purposes.

Spatial distribution and ecological risks of polychlorinated biphenyls in a river basin affected by traditional and emerging electronic waste recycling in South China.

With development of e-waste related legislation in China, formal recycling activities are designated in some areas while informal ones are illegally transferred to emerging areas to avoid supervision. However, the resulting environmental impact and ecological risks are not clear. Here, we investigated the discharge of polychlorinated biphenyls (PCBs) to soil and aquatic environments by e-waste recycling activities in the Lian River Basin, China. The study area included a designated industrial park in the traditional e-waste recycling area (Guiyu, known as the world's largest e-waste center), several emerging informal recycling zones, and their surrounding areas and coastal area. A total of 27 PCBs were analyzed, and the highest concentration was found in an emerging site for soil (354 ng g-1) and in a traditional site for sediment (1350 ng g--1) respectively. The pollution levels were significantly higher in both the traditional and emerging recycling areas than in their respective upstream countryside areas (p = 0.0356 and 0.0179, respectively). Source analysis revealed that the traditional and emerging areas had similar PCB sources mainly associated with three PCB technical mixtures manufactured in Japan (KC600) and the USA (Aroclor 1260 and Aroclor 1262). The PCB pollution in their downstream areas including the coastal area was evidently affected by the formal and informal recycling activities through river runoff. The ecological risk assessments showed that PCBs in soils and sediments in the Lian River Basin could cause adverse ecotoxicological consequences to humans and aquatic organisms.

Tris(2,4-di-tert-butylphenyl)phosphate: An Unexpected Abundant Toxic Pollutant Found in PM2.5.

A novel pollutant, tris(2,4-di-tert-butylphenyl)phosphate (I168O), was identified in urban fine particulate matter (PM2.5) samples in a nontargeted screening based on mass spectrometry for the first time. I168O was detected in all samples collected from two typical cities far away from each other in China. The concentrations of I168O reached up to 851 (median: 153) ng/m3, indicating that it was a widespread and abundant pollutant in the air. The antioxidant Irgafos 168 [I168, tris(2,4-di-tert-butylphenyl)phosphite] popularly added in plastics was the most suspected source for the detected I168O. Simulation studies indicated that heating, UV radiation, and water contact might significantly (p < 0.05) transform I168 to I168O. In particular, I168O might be magnificently evaporated into the air at high temperatures. The outdoor inhalation exposure of I168O may exert substantial health risks.

Multigenerational Impacts of Benzo[a]pyrene on Bone Modeling and Remodeling in Medaka (Oryzias latipes).

Ancestral benzo[a]pyrene (BaP) (1 µg/L, 21 days) exposure has previously been shown to cause skeletal deformities in medaka (Oryzias latipes) larvae in the F1-F3 generation. However, when and how this deformity is induced during bone development remain to be elucidated. The col10a1:nlGFP/osx:mCherry double transgenic medaka model was employed to determine the temporal and spatial changes of col10a1:nlGFP- positive osteochondral progenitor cells (OPCs) and osx:mCherry-positive premature osteoblasts (POBs) [8 days postfertilization (dpf)-31 dpf] in combination with changes in bone mineralization at the tissue level. Ancestral BaP exposure delayed the development of col10a1:nlGFP- and osx:mCherry-positive osteoblasts and reduced the abundance of col10a1:nlGFP-positive osteoblast progenitors and col10a1:nlGFP/osx:mCherry double-positive premature osteoblasts during critical windows of early vertebral bone formation, associated with reduced bone mineralization in embryos (14 dpf) and larvae (31 dpf), compressed vertebral segments in larvae (31 dpf), and reduced bone thickness in adult male medaka (6 months old) of the F1-F3 generations. Both Col10a1:nlGFP and osx:mCherry were identified as potential targets of epigenetic modifications underlying the transgenerational inheritance of BaP bone toxicity. The present study provides novel knowledge of the underlying mechanisms of transgenerational toxicity of BaP at the cellular level.

Organic pollutants in sedimentary microplastics from eastern Guangdong: Spatial distribution and source identification.

Microplastics have a strong affinity for potentially toxic organic pollutants such as polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs). Since 2005, the International Pellet Watch used plastic pellets to monitor hydrophobic organic contaminants in marine environments. We examined the spatial distribution and sources of 16 PAHs and eight OCPs on microplastics (pellets, fragments, and foam) collected from eastern Guangdong beaches with the goal of evaluating the feasibility of exclusively using pellets in global monitoring of hydrophobic organic contaminants. The ∑PAH and ∑OCP concentrations ranged from 11.2 to 7710 ng g-1 and 2.2-1970 ng g-1, respectively. Although inter-site and regional differences were insignificant in fragments and foam, regional differences were observed in ∑OCP concentrations on pellets samples collected at the estuary mouth and the distributary (p < 0.05). No regional difference in ∑PAH concentration on microplastics was observed, except between fragments from the remote beach and those from the distributary (p = 0.015) and the estuary mouth (p = 0.015). The compositional profiles of PAHs revealed that PAHs with 2-4 rings were more dominant than those with >4 rings. Considering low molecular weight PAHs are less hydrophobic and more toxic; the results suggest low molecular weight PAHs may pose a significant risk to marine organisms. This study shows that the International Pellet Watch could offer critical data on source and transport of microplastic-associated OCPs but may overlook critical vehicles of PAHs in coastal environments such as foam.

Residual effects of organochlorine pesticides (OCPs) in an e-waste recycling area compared with heavy metal pollution.

Disposal of e-waste is a global issue and has caused serious pollution in recycling areas. Most of these areas had once developed intensive agriculture and might incur organochlorine pesticides (OCPs) pollution. However, this used to be neglected. Here we discuss the joint effects via analyzing OCPs and heavy metals in a notorious e-waste recycling area. The OCPs showed higher (p = 0.005) pollution levels in soils from agricultural zone than in core e-waste recycling zone, which is opposite for heavy metals (p = 0.02). The OCPs and heavy metals showed the highest concentrations in the open burning site locating in the boundary between the e-waste and agricultural zones. Composition profiles further indicated that the land use changes from agriculture to e-waste industry might accelerate the release of buried OCPs. Worse still, the OCPs and heavy metals might pose carcinogenic and non-carcinogenic risks to local residents, respectively.

The health concern of polychlorinated biphenyls (PCBs) in a notorious e-waste recycling site.

Polychlorinated biphenyls (PCBs) remain a relatively high level in e-waste recycling regions 3 decades after ban on use. Illegal recycling activities cunningly moved under the environmental law enforcement. Here, we analyzed PCBs in soils and plants from Guiyu, China (one of the world's largest recycling areas) to understand the relationship between PCBs pollution and the transition of recycling activities (locations and techniques). High concentrations of PCBs were found in soil and plant samples from emerging recycling sites, up to 234 ng g-1 and 236 ng g-1 (dry weight), respectively. The recycling activities, specifically the open burning process, would obviously aggravate the PCB pollution levels in its environment. The calculated values of estimated daily intake and hazard ratios of PCBs in dietary routes showed that health risks should be taken seriously.

Determinants of exposure levels, metabolism, and health risks of phthalates among pregnant women in Wuhan, China.

Concerns on minimizing health risks of phthalates have been raised due to their widespread exposure and well-documented endocrine disrupting properties, but the determinants of levels, metabolism, and health risks of phthalate exposures have not been thoroughly characterized among the Chinese population, particularly pregnant women. The metabolites of five phthalates were analyzed: diethyl (DEP), diisobutyl (DiBP), di-n-butyl (DnBP), di-(2-ethylhexyl) (DEHP), and benzyl butyl phthalate (BBzP) were analyzed in urine samples collected from 946 mothers in Wuhan during 2014-2015. We applied linear mixed models to investigate the relationships between biomarkers (e.g., urinary concentrations of phthalate metabolites, phthalates, and ratios of metabolites) and factors including sampling seasons and epidemiological characteristics. We calculated estimated daily intake (EDI) using average phthalate concentrations over three trimesters and hazard index (HI) by dividing EDI by tolerance daily intake. About 24.9% of participants were at health risks with HI > 1. The largest health risks were driven by one specific phthalate (DnBP or DEHP). We observed lower urinary levels of phthalate metabolites in winter. Elevated levels were found in mothers with higher education levels or those employed. Mothers who got pregnant on purpose had lower phthalate concentrations than those got pregnant by accident. More recent exposure to phthalates was observed among groups of mothers giving birth to girls, or those who got excessive gestational weight gain. Younger mothers were more susceptible to phthalate exposure. This repeated measurement study suggests that the intervention should be taken to limit application and production of DnBP and DEHP, and highlights that typical demographic factors should be taken into account in demographic studies.

Health risks of polycyclic aromatic hydrocarbons via fish consumption in Haimen bay (China), downstream of an e-waste recycling site (Guiyu).

Guiyu, China has been one of the largest e-waste recycling sites of the world for more than 20 years. Abundant data show that local dwellers there suffered from severe health risks from e-waste contaminants. In this study, polycyclic aromatic hydrocarbons (PAHs) were used as candidates to test the contamination levels and their possible adverse effects on residents in Haimen Bay, the estuary of Lian River (less than 30km from Guiyu), which has been totally neglected. The concentrations of 16PAHs were determined in collected marine fish with a median ΣPAH concentration of 1478ng/g (wet weight), and the contamination may be mainly influenced by Lian River runoff, specifically from Guiyu. The lifetime excess cancer risk for local dwellers was much higher than the serious risk level (10(-4)). More seriously, outflows of PAHs from the e-waste recycling site (Guiyu) seemed to exert health risks of a much larger scale of population downstream.

One-step enrichment of phenolics from Chaenomeles speciosa (Sweet) Nakai fruit using macroporous resin: Adsorption/desorption characteristics, process optimization and UPLC-QqQ-MS/MS-based quantification.

Chaenomeles speciosa (Sweet) Nakai fruit is a good source of phenolics with many health benefits. In this work, the enrichment of C. speciosa fruit total phenolics (CSFTP) using macroporous resins was studied. NKA-Ⅱ resin was selected for enriching CSFTP due to its highest adsorption/desorption quantity. Adsorption characteristics of CSFTP on NKA-Ⅱ resin exhibited a good fit with the Langmuir isotherm model and pseudo-second order kinetics model. This adsorption was spontaneous, exothermic, and entropy-decreasing through a physisorption mechanism. The breakthrough-elution curves were studied to optimize CSFTP enrichment conditions. One-step enrichment increased CSFTP content in the extracts from 26.51 % to 78.63 %, with a recovery of 81.03 %. A UPLC-QqQ-MS/MS method in multiple reaction monitoring (MRM) mode was established and validated for the simultaneous quantification of seven phenolic compounds. This study demonstrates the feasibility of industrial enrichment of CSFTP using NKA-Ⅱ resin and proposes a reliable method for quality control of CSFTP-rich products.

Integrated metabolomics and serum-feces pharmacochemistry-based network pharmacology to reveal the mechanisms of an herbal prescription against ulcerative colitis.

BACKGROUND: CDD-2103 is an herbal prescription used to treat ulcerative colitis (UC). This study aimed to uncover its mechanism by integrating metabolomics and serum-feces pharmacochemistry-based network pharmacology. METHODS: A DSS-induced chronic colitis mice model was used to evaluate the anti-colitis effect of CDD-2103. Serum and feces metabolomics were conducted to identify differential metabolites and pathways. In the serum-feces pharmacochemistry study, biological samples were collected from rats treated with CDD-2103. Then, network pharmacology was utilized to predict the targets of the identified compounds. Critical genes were extracted through the above-integrated analysis. The interactions between targets, CDD-2103, and its compounds were validated through molecular docking, immunoblotting, and enzyme activity assays. RESULTS: CDD-2103 alleviated ulcerous symptoms and colonic injuries in colitis mice. Metabolomics study identified differential metabolites associated with tryptophan, glycerophospholipid, and linoleic acid metabolisms. The serum-feces pharmacochemistry study revealed twenty-three compounds, which were subjected to network pharmacology analysis. Integration of these results identified three key targets (AHR, PLA2, and PTGS2). Molecular docking showed strong affinities between the compounds and targets. PTGS2 was identified as a hub gene targeted by most CDD-2103 compounds. Immunoblotting and enzyme activity assays provided further evidence that CDD-2103 alleviates UC, potentially through its inhibitory effect on cyclooxygenase-2 (COX-2, encoded by PTGS2), with alkaloids and curcuminoids speculated as crucial anti-inflammatory compounds. CONCLUSION: This integrated strategy reveals the mechanism of CDD-2103 and provides insights for developing herbal medicine-based therapies for UC.

OCPs and PCBs in marine edible fish and human health risk assessment in the eastern Guangdong, China.

Marine edible fish samples were collected from two important nearshore fishing sites in the eastern Guangdong Province, China: Shantou Harbor and Haimen Bay. In the mixed edible muscle tissues of marine fish samples, the concentrations of polychlorinated biphenyls, dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), chlordanes, and hexachlorobenzene ranged from 1.12 to 53.87, ND (not detected) to 84.01, 0.22 to 7.09, ND to 4.74, and ND to 1.49 ng/g wet weight (ww) in Haimen Bay, respectively, and from ND to 70.35, ND to 164.83, ND to 8.68, ND to 25.61, and ND to 1.76 ng/g ww in Shantou Harbor, respectively. The concentrations of PCBs, DDTs, and HCHs in all samples did not exceed maximum residue limits (China and United States Food and Drug Administration). However, a few fish samples exceed the maximum levels established by the European Union. Daily fish consumption from this region can be of serious concern, and lifetime cancer risk remains a possibility in the studied area.

Cumulative health risks for bisphenols using the maximum cumulative ratio among Chinese pregnant women.

Bisphenol A and its alternatives are frequently detected in environmental and human samples, but studies associated with the pattern of combined health hazards from the exposure to the bisphenol mixtures are lacking, particularly for pregnant women. Here, we recruited 941 pregnant women with a full set of urine samples in the three trimesters collected under a cohort study project in Wuhan, China, between 2014 and 2015. We measured the concentrations of 8 bisphenols in 2823 urine samples, and calculated the average concentrations of bisphenols, which were detected in over 50% of samples, once during each trimester of pregnancy. We calculated the maximum cumulative ratio (MCR) on basis of estimated daily intake (EDI), hazard quotient (HQ), hazard index (HI) of three major bisphenols, including bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS), to find which one or mixtures drive risks. Participants were categorized into four groups according to their maximum HQ, HI and MCR values. We found negative relationships between log(MCR-1) and log(HI) with the slope (-0.6431). Percentage of HQ of BPA in HI ranged from 37.1% (<25th percentiles of HI) to 75.5% (>95th percentiles of HI) indicating the upward trend of dominance by BPA at increasing HI ranges. The cumulative health risks of bisphenol exposures largely originated from the health hazards of BPA and BPS, particularly BPA. The intervention for regulation on the production and application of BPA and its alternatives are urgent, and China should consider national regulation on these chemicals based on its risk to human health.

Toxicological effects benzotriazole to the marine scallop Chlamys nobilis: a 2-month exposure study.

Benzotriazole and its associated derivatives (BTs) are widely used as ultraviolet stabilizers and corrosion inhibitors. They have been extensively found in marine environments and are bioaccumulative through the food chain. However, the toxicities of BTs to marine organisms are seldom identified and no assessment has been conducted for filter-feeding bivalves. In this study, a marine scallop Chlamys nobilis was exposed to 0, 0.01, 0.1, and 1.0 mg/L of BT for 60 days. Effects of BT on endocrine system, cytochrome P450 activity, antioxidant activity, and neural activity of C. nobilis were examined. The results showed that BT exerted significant estrogenic effects on both male and female scallops and inhibited EROD activities of C. nobilis even at 0.01 mg/L level. BT at ≥ 0.01 mg/L levels also caused significant oxidative stress on C. nobilis. Moreover, most of the adverse effects of BT to C. nobilis were found from day 35 and 0.01 mg/L was the lowest concentration with observed effects, showing the long-term toxic effects of BT to C. nobilis. Thus, the adverse effects of BT and its derivatives to marine benthic communities deserve more attention in future research.

Integrated assessment of heavy metal pollution using transplanted mussels in eastern Guangdong, China.

Heavy metal contamination has been widely studied in coastal areas around the world. However, integrative studies of heavy metals pollution by monitoring and characterizing sediments, organisms, and biomarkers as well as their holistic interactions are rare. Here, we selected a developed coastal area in eastern Guangdong, China as the study field. Heavy metal analysis (both in sediment and mussel) and biomarker tests, including neutral red retention time test (NRRT) and micronuclei (MN) test, were employed in the current research. Anthropogenic activities influenced the heavy metal levels in sediments. Significant relationships (p < 0.05) were observed in the concentrations of Cd, Cu, and Zn between sediments and transplanted mussel, and significant relationships (p < 0.05) were also observed in between the concentrations of Cd, Cu, and Zn in sediments and the NRRT of mussel. The potential ecological risk index (RI) of sediments significantly correlated with NRRT (R = -0.991, p < 0.05). In Hao River, where the highest RI of sediments was found, the highest MN frequency and the lowest NRRT in mussels were detected simultaneously. The results indicated that the heavy metal pollution might cause subcellular toxic and genotoxic effects on mussels, especially for those from polluted areas (i.e., Hao River). The present study suggests that the transplanted green-lipped mussels are suitable for assessing heavy metal pollution, especially for Cd, Cu, and Zn.

Polychlorinated biphenyls and organochlorine pesticides in surface sediments from Shantou Bay, China: Sources, seasonal variations and inventories.

Sediments from Shantou Bay, China, were analyzed for polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) for the first time. The concentrations of PCBs and OCPs were 0.54-55.5ngg-1 and 2.19-16.9ngg-1 (dry weight), respectively. Source identification showed that tri-CBs and penta-CBs were manufactured and used in the last century, while usage of antifouling paint might still serve as a significant source of sediment DDT. Concentrations of PCBs and HCHs significantly (p<0.05) increased after wet season, suggesting that atmospheric deposition and surface runoff played an important role in distribution of historical pollutants. Additionally, the adverse biological effects could occasionally occur for DDT in sediments. The mass inventories were preliminarily calculated for PCBs (90.1ngcm-2 and 0.09tons) and OCPs (61.8ngcm-2 and 0.062tons) in Shantou Bay, while as part of the "reservoir" of organochlorine compounds to the global ocean, its role cannot be neglected.

Evaluation of organochlorine contamination in Indo-Pacific humpback dolphins (Sousa chinensis) from the Pearl River Estuary, China.

Organochlorine compounds, including polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane (DDTs), hexachlorocyclohexane (HCHs), chlordanes (CHLs) and hexachlorobenzene (HCB) were analyzed in blubber samples collected from fifteen Indo-Pacific humpback dolphins (Sousa chinensis) stranded in the Pearl River Delta during the period from 2004 to 2009. In general, the magnitude of the mean concentrations is: ∑DDTs>∑PCBs>∑HCHs>∑CHLs>HCB. DDT levels found in this study were very high, with the ΣDDT ranging from 845 to 179,000 ng/g wet weight. Of particular importance is the fact that new inputs from diverse sources still exist in the Pearl River Delta. ∑PCBs ranged from 123 to 10,200 ng/g wet weight. More studies are necessary for a better understanding of these organochlorine contaminants and their impact on the conservation of humpback dolphins residing in the Pearl River Estuary waters.