Toxicity Attenuation Mechanism on Processing Method for Aconiti Lateralis Radix Praeparata in Guilingji Based on Urine Metabolomics / 中国实验方剂学杂志

ObjectiveMetabolomics was used to reveal the mechanism of Aconiti Lateralis Radix Praeparata（ALRP） in attenuating toxicity by processing from the aspects of amino acid metabolism， oxidative stress and energy metabolism by analyzing multiple metabolic pathways. MethodTwenty-four rats were randomly divided into control group， raw group and processed group， 8 rats in each group. The raw and processed group were given with 0.64 g·kg-1 of raw ALRP and processed ALRP respectively every day， the control group was given with an equal amount of normal saline once a day. After continuous administration for 7 days， the urine， serum and heart tissue of rats were collected. Pathological examination of the heart was carried out using hematoxylin-eosin（HE） staining， and the activities of lactate dehydrogenase（LDH） and creatine kinase-MB（CK-MB） in serum and cardiac tissues were detected by microplate assay and immunoinhibition assay. The effects of ALRP on rat heart before and after processing were compared and analyzed. Ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry（UPLC-Q-TOF-MS） was used to perform urine metabolomics analysis， and multivariate statistical analysis was used to screen for differential metabolites related to ALRP in attenuating toxicity by processing， and pathway enrichment analysis was carried out to explore the processing mechanism. ResultHE staining showed that no obvious pathological changes were observed in the heart tissue of the control group， while obvious infiltration of inflammatory cells such as plasma cells and granulocytes was observed in the heart tissue of the raw group， indicating that the raw ALRP had strong cardiotoxicity. There was no significant difference in HE staining of heart tissue between the processed group and the control group， indicating that the toxicity of ALRP was significantly reduced after processing. Compared with the control group， the activities of LDH and CK-MB were significantly increased in serum and heart tissue of the raw group， and those were significantly decreased in serum and heart tissue of the processed group， suggesting that the myocardial toxicity of processed ALRP was reduced. A total of 108 endogenous differential metabolites associated with the raw ALRP were screened using multivariate statistical analysis in positive and negative modes， of which 51 differential metabolites were back-regulated by the processed ALRP. Biological analysis of the key regulatory pathways and associated network changes showed that the pathways related to toxicity of ALRP mainly included tryptophan metabolism， arginine and proline metabolism， phenylalanine metabolism， aminoacyl-tRNA biosynthesis， alanine， aspartate and glutamate metabolism， etc. The metabolic pathways related to the attenuation of processed ALRP mainly included aminoacyl-tRNA biosynthesis， tryptophan metabolism， phenylalanine， tyrosine and tryptophan biosynthesis， phenylalanine metabolism and caffeine metabolism. ConclusionThe processing technology of ALRP in Guilingji can significantly attenuate the cardiotoxicity of raw products， the mechanism mainly involves amino acid metabolism， oxidative stress and energy metabolism， which can provide experimental bases for the research related to the mechanism of toxicity reduction of ALRP by processing and its clinical safety applications.

Nicotine and Cytisine Embryotoxicity in the Experimental Zebrafish Model.

Tobacco smoking is one of the most serious health problems. Potentially lethal effects of nicotine for adults can occur with as little as 30 to 60 mg, although severe symptoms can arise with lower doses. Furthermore, the route of administration also influences the toxicity. Cytisine is one of the most popular medications in nicotinism treatment. Like nicotine, cytisine is a plant alkaloid, signaling through nicotinic acetylcholine receptors. Our study evaluated the effects of cytisine in nicotine-induced embryotoxic effects using zebrafish larvae. We examined the teratogenicity of nicotine and cytisine alone or in combination. Nicotine increased mortality and delayed hatching of zebrafish larvae in a dose-dependent manner. Cytisine did not affect mortality in a wide range of concentrations, and hatching delay was observed only at the highest concentrations, above 2 mM. Administering compounds together partially reduced the adverse teratogenic effect induced by nicotine alone. The protective effect of cytisine against the nicotine effect, observed in zebrafish, will contribute to future studies or treatments related to nicotine addiction or prenatal nicotine exposure in humans.

[Toxicity attenuation processing technology and mechanism of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction].

This study explored toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction for the first time, and further explored its detoxification mechanism. Nine processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction were prepared by orthogonal experiment with three factors and three levels. Based on the decrease in the content of the main hepatotoxic component diosbulbin B before and after processing of Rhizoma Dioscoreae Bulbiferae by high-performance liquid chromatography, the toxicity attenuation technology was preliminarily screened out. On this basis, the raw and representative processed products of Rhizoma Dioscoreae Bulbiferae were given to mice by gavage with 2 g·kg~(-1)(equival to clinical equivalent dose) for 21 d. The serum and liver tissues were collected after the last administration for 24 h. The serum biochemical indexes reflecting liver function and liver histopathology were combined to further screen out and verify the proces-sing technology. Then, the lipid peroxidation and antioxidant indexes of liver tissue were detected by kit method, and the expressions of NADPH quinone oxidoreductase 1(NQO1) and glutamate-cysteine ligase(GCLM) in mice liver were detected by Western blot to further explore detoxification mechanism. The results showed that the processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reduced the content of diosbulbin B and improved the liver injury induced by Rhizoma Dioscoreae Bul-biferae to varying degrees, and the processing technology of A_2B_2C_3 reduced the excessive levels of alanine transaminase(ALT) and aspartate transaminase(AST) induced by raw Rhizoma Dioscoreae Bulbiferae by 50.2% and 42.4%, respectively(P<0.01, P<0.01). The processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reversed the decrease protein expression levels of NQO1 and GCLM in the liver of mice induced by raw Rhizoma Dioscoreae Bulbiferae to varying degrees(P<0.05 or P<0.01), and it also reversed the increasing level of malondialdehyde(MDA) and the decreasing levels of glutathione(GSH), glutathione peroxidase(GPX), and glutathione S-transferase(GST) in the liver of mice(P<0.05 or P<0.01). In summary, this study shows that the optimal toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction is A_2B_2C_3, that is, 10% of Paeoniae Radix Alba decoction is used for moistening Rhizoma Dioscoreae Bulbiferae and processed at 130 ℃ for 11 min. The detoxification mechanism involves enhancing the expression levels of NQO1 and GCLM antio-xidant proteins and related antioxidant enzymes in the liver.

Sorting and Elaborating on the Combination Theory of Herb Pairs / 中医杂志

As the smallest combination unit of Chinese medicinals， herbal pairs serve as the bridge between medicinals and formulas， whose combination theory reflects the basic characteristics of Chinese medicinals combination and the core essence of prescription composition. Simultaneously， as a key combination of medicinals in clinical treatment of diseases， syndromes， and symptoms， herbal pairs are the main form of clinical medication in traditional Chinese medicine （TCM） as well as the characteristic advantage of treating diseases. This article summarized that “mutual complement of medicinals of same or antagonism flavor and nature” theory is the theoretical origin， and efficacy-enhancement and toxicity-attenuation is the core purpose of the combination of herbal pairs. The property theory of Chinese medicinals and the thought of differentiation and treatment are the main basis of the combination of herbal pairs， and pertinence and flexibility are the key points in clinical application. All mentioned above are expected to provide theoretical guidance for the clinical use and modern research of herbal pairs.

Toxicity attenuation processing technology and mechanism of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction / 中国中药杂志

This study explored toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction for the first time, and further explored its detoxification mechanism. Nine processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction were prepared by orthogonal experiment with three factors and three levels. Based on the decrease in the content of the main hepatotoxic component diosbulbin B before and after processing of Rhizoma Dioscoreae Bulbiferae by high-performance liquid chromatography, the toxicity attenuation technology was preliminarily screened out. On this basis, the raw and representative processed products of Rhizoma Dioscoreae Bulbiferae were given to mice by gavage with 2 g·kg~(-1)(equival to clinical equivalent dose) for 21 d. The serum and liver tissues were collected after the last administration for 24 h. The serum biochemical indexes reflecting liver function and liver histopathology were combined to further screen out and verify the proces-sing technology. Then, the lipid peroxidation and antioxidant indexes of liver tissue were detected by kit method, and the expressions of NADPH quinone oxidoreductase 1(NQO1) and glutamate-cysteine ligase(GCLM) in mice liver were detected by Western blot to further explore detoxification mechanism. The results showed that the processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reduced the content of diosbulbin B and improved the liver injury induced by Rhizoma Dioscoreae Bul-biferae to varying degrees, and the processing technology of A_2B_2C_3 reduced the excessive levels of alanine transaminase(ALT) and aspartate transaminase(AST) induced by raw Rhizoma Dioscoreae Bulbiferae by 50.2% and 42.4%, respectively(P<0.01, P<0.01). The processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reversed the decrease protein expression levels of NQO1 and GCLM in the liver of mice induced by raw Rhizoma Dioscoreae Bulbiferae to varying degrees(P<0.05 or P<0.01), and it also reversed the increasing level of malondialdehyde(MDA) and the decreasing levels of glutathione(GSH), glutathione peroxidase(GPX), and glutathione S-transferase(GST) in the liver of mice(P<0.05 or P<0.01). In summary, this study shows that the optimal toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction is A_2B_2C_3, that is, 10% of Paeoniae Radix Alba decoction is used for moistening Rhizoma Dioscoreae Bulbiferae and processed at 130 ℃ for 11 min. The detoxification mechanism involves enhancing the expression levels of NQO1 and GCLM antio-xidant proteins and related antioxidant enzymes in the liver.

Sorting and Elaborating on the Combination Theory of Herb Pairs / 中医杂志

@#As the smallest combination unit of Chinese medicinals， herbal pairs serve as the bridge between medicinals and formulas， whose combination theory reflects the basic characteristics of Chinese medicinals combination and the core essence of prescription composition. Simultaneously， as a key combination of medicinals in clinical treatment of diseases， syndromes， and symptoms， herbal pairs are the main form of clinical medication in traditional Chinese medicine （TCM） as well as the characteristic advantage of treating diseases. This article summarized that “mutual complement of medicinals of same or antagonism flavor and nature” theory is the theoretical origin， and efficacy-enhancement and toxicity-attenuation is the core purpose of the combination of herbal pairs. The property theory of Chinese medicinals and the thought of differentiation and treatment are the main basis of the combination of herbal pairs， and pertinence and flexibility are the key points in clinical application. All mentioned above are expected to provide theoretical guidance for the clinical use and modern research of herbal pairs.

[Compatibility for toxicity attenuation of toxic traditional Chinese medicine: a review and strategies].

Toxicity-attenuating compatibility is an effective measure to ensure the safety of Chinese medicine. Involving the origin, processing method, compatibility mode, and dosage, it faces multiple challenges, such as the uncertainty of toxic substances, toxicity latency, indefinite safe dose, complex toxicity-efficacy relationship, and individual difference. As a result, research on clinical safety of Chinese medicine is limited by the consistency at "molecular-cellular-organ-overall" levels, unclear interaction of multiple medicinals and multiple substances, the "toxicity-efficacy-compatibility-syndrome" correlation, and the "dosage-time-toxicity-efficacy" conversion law. Therefore, following the principle of "starting from the clinical practice, verifying via the theoretical basis, and finally applying in clinical practice", we verified the toxicity at "molecular-cellular-organ-overall" levels, revealed the interaction of multiple medicinals and substances, collected evidence at multiple levels, clarified the "dosage-time-toxicity-efficacy" relationship, and tested the consistency between basic and clinical biomarkers. On this basis, we studied the toxicity-alleviating and efficacy-enhancing(preserving) compatibility characteristics, the fate of one medicinal and multiple medicinals in vivo, the molecular mechanism of toxicity, the "dosage-time-toxicity-efficacy" conversion law, and the clinical characteristics of toxic traditional Chinese medicine based on disease and syndrome. The three mechanisms of toxicity-attenuating compatibility reflect the seven-reaction theory in Chinese medicine compatibility. Finally, the strategies for safe use of Chinese medicine were proposed.

Unveiling Dynamic Changes of Chemical Constituents in Raw and Processed Fuzi With Different Steaming Time Points Using Desorption Electrospray Ionization Mass Spectrometry Imaging Combined With Metabolomics.

Fuzi is a famous toxic traditional herbal medicine, which has long been used for the treatment of various diseases in China and many other Asian countries because of its extraordinary pharmacological activities and high toxicity. Different processing methods to attenuate the toxicity of Fuzi are important for its safe clinical use. In this study, desorption electrospray ionization mass spectrometry imaging (DESI-MSI) with a metabolomics-combined multivariate statistical analysis approach was applied to investigate a series of Aconitum alkaloids and explore potential metabolic markers to understand the differences between raw and processed Fuzi with different steaming time points. Moreover, the selected metabolic markers were visualized by DESI-MSI, and six index alkaloids' contents were determined through HPLC. The results indicated visible differences among raw and processed Fuzi with different steaming times, and 4.0 h is the proper time for toxicity attenuation and efficacy reservation. A total of 42 metabolic markers were identified to discriminate raw Fuzi and those steamed for 4.0 and 8.0 h, which were clearly visualized in DESI-MSI. The transformation from diester-diterpenoid alkaloids to monoester-diterpenoid alkaloids and then to non-esterified diterpene alkaloids through hydrolysis is the major toxicity attenuation process during steaming. DESI-MSI combined with metabolomics provides an efficient method to visualize the changeable rules and screen the metabolic markers of Aconitum alkaloids during steaming. The wide application of this technique could help identify markers and reveal the possible chemical transition mechanism in the "Paozhi" processes of Fuzi. It also provides an efficient and easy way to quality control and ensures the safety of Fuzi and other toxic traditional Chinese medicine.

[Twenty years in the 21st century: research hotspots and frontier analysis on Chinese medicine processing mechanism].

The research on the processing mechanism of Chinese medicine is the key and core foundation to improve processing technologies of Chinese medicine, formulate the quality standards of Chinese medicinal pieces, enhance the clinical efficacy of Chinese medicine, enrich Chinese medicine processing theories, and promote the development of Chinese medicine processing. Many researc-hers have conducted in-depth exploration on the processing mechanism of Chinese medicine in the 20 years in the 21 st century. Significant progress has been made in the transformation of chemical components during the processing, the change of active components in the body, the law of toxicity attenuation in the processing of toxic Chinese medicine, the mechanism of efficacy enhancement and toxicity attenuation of processing with auxiliary materials, and the application of new biomedical technologies. At present, the processing mechanism of multiple Chinese medicines has been preliminarily clarified, which has greatly promoted the development of Chinese me-dicine processing. The development of the processing mechanism of Chinese medicine reveals that the in vitro transformation of chemical components is combined with the in vivo absorption, transport, and metabolism, and the macroscopic biological effects of the organism are combined with the cells, molecules, targets, and pathways in the study of the processing mechanism of Chinese medicine. More attention has been paid to exploring the processing mechanism from the overall level, and a modern systematic research system on the processing mechanism of Chinese medicine has been initially formed. To further promote the scientific development of Chinese me-dicine processing, the present study proposed that the research on the processing mechanism of Chinese medicine should take Chinese medicine properties into account, focus on the influence of disease condition on the mode of action and effect strength of the drugs, comply with the characteristics of clinical compound compatibility of Chinese medicine, use the holistic view research strategies of systems bio-logy, and deeply explore the processing mechanism of Chinese medicine from traditional Chinese medicine theories and the characteristics of clinical medication of Chinese medicine.

Toxicity of Tetradium ruticarpum: Subacute Toxicity Assessment and Metabolomic Identification of Relevant Biomarkers.

Tetradium ruticarpum (TR) is widely used in Asia to treat gastrointestinal disorders and pain. Stir-frying with licorice aqueous extract is a traditional processing procedure of TR formed in a long-term practice and performed before clinical application, and believed to reduce TR's toxicity. However, its toxicity and possible toxicity attenuation approach are yet to be well investigated. Subacute toxicity and metabolomics studies were conducted to help understand the toxicity of TR. The subacute toxicity assessment indicated that 3 fold of the recommended therapeutic dose of TR did not show obvious subacute toxicity in rats. Although an extremely high dose (i.e., 60 fold of the recommended dose) may cause toxicity in rats, it reversed to normal after 2 weeks of recovery. Hepatocellular injury was the major toxic phenotype of TR-induced liver damage, indicating as aspartate aminotransferase (AST) and liver index increasing, with histopathologic findings as local hepatocyte necrosis, focal inflammatory cell infiltration, slightly bile duct hyperplasia, and partial hepatocyte vacuolation. Moreover, we evaluated the impact of processing in toxicity. TR processed with licorice could effectively reduce drug-induced toxicity, which is a valuable step in TR pretreatment before clinical application. Metabolomics profiling revealed that primary bile acid biosynthesis, steroid biosynthesis, and arachidonic acid metabolism were mainly involved in profiling the toxicity metabolic regulatory network. The processing procedure could back-regulate these three pathways, and may be in an Aryl hydrocarbon Receptor (AhR) dependent manner to alleviate the metabolic perturbations induced by TR. 7α-hydroxycholesterol, calcitriol, and taurocholic acid were screened and validated as the toxicity biomarkers of TR for potential clinical translation. Overall, the extensive subacute toxicity evaluation and metabolomic analysis would not only expand knowledge of the toxicity mechanisms of TR, but also provide scientific insight of traditional processing theory, and support clinical rational use of TR.

Compatibility for toxicity attenuation of toxic traditional Chinese medicine: a review and strategies / 中国中药杂志

Toxicity-attenuating compatibility is an effective measure to ensure the safety of Chinese medicine. Involving the origin, processing method, compatibility mode, and dosage, it faces multiple challenges, such as the uncertainty of toxic substances, toxicity latency, indefinite safe dose, complex toxicity-efficacy relationship, and individual difference. As a result, research on clinical safety of Chinese medicine is limited by the consistency at "molecular-cellular-organ-overall" levels, unclear interaction of multiple medicinals and multiple substances, the "toxicity-efficacy-compatibility-syndrome" correlation, and the "dosage-time-toxicity-efficacy" conversion law. Therefore, following the principle of "starting from the clinical practice, verifying via the theoretical basis, and finally applying in clinical practice", we verified the toxicity at "molecular-cellular-organ-overall" levels, revealed the interaction of multiple medicinals and substances, collected evidence at multiple levels, clarified the "dosage-time-toxicity-efficacy" relationship, and tested the consistency between basic and clinical biomarkers. On this basis, we studied the toxicity-alleviating and efficacy-enhancing(preserving) compatibility characteristics, the fate of one medicinal and multiple medicinals in vivo, the molecular mechanism of toxicity, the "dosage-time-toxicity-efficacy" conversion law, and the clinical characteristics of toxic traditional Chinese medicine based on disease and syndrome. The three mechanisms of toxicity-attenuating compatibility reflect the seven-reaction theory in Chinese medicine compatibility. Finally, the strategies for safe use of Chinese medicine were proposed.

Twenty years in the 21st century: research hotspots and frontier analysis on Chinese medicine processing mechanism / 中国中药杂志

The research on the processing mechanism of Chinese medicine is the key and core foundation to improve processing technologies of Chinese medicine, formulate the quality standards of Chinese medicinal pieces, enhance the clinical efficacy of Chinese medicine, enrich Chinese medicine processing theories, and promote the development of Chinese medicine processing. Many researc-hers have conducted in-depth exploration on the processing mechanism of Chinese medicine in the 20 years in the 21 st century. Significant progress has been made in the transformation of chemical components during the processing, the change of active components in the body, the law of toxicity attenuation in the processing of toxic Chinese medicine, the mechanism of efficacy enhancement and toxicity attenuation of processing with auxiliary materials, and the application of new biomedical technologies. At present, the processing mechanism of multiple Chinese medicines has been preliminarily clarified, which has greatly promoted the development of Chinese me-dicine processing. The development of the processing mechanism of Chinese medicine reveals that the in vitro transformation of chemical components is combined with the in vivo absorption, transport, and metabolism, and the macroscopic biological effects of the organism are combined with the cells, molecules, targets, and pathways in the study of the processing mechanism of Chinese medicine. More attention has been paid to exploring the processing mechanism from the overall level, and a modern systematic research system on the processing mechanism of Chinese medicine has been initially formed. To further promote the scientific development of Chinese me-dicine processing, the present study proposed that the research on the processing mechanism of Chinese medicine should take Chinese medicine properties into account, focus on the influence of disease condition on the mode of action and effect strength of the drugs, comply with the characteristics of clinical compound compatibility of Chinese medicine, use the holistic view research strategies of systems bio-logy, and deeply explore the processing mechanism of Chinese medicine from traditional Chinese medicine theories and the characteristics of clinical medication of Chinese medicine.

Ameliorating effect of nitrate on nitrite inhibition for denitrifying P-accumulating organisms.

Lowered air supply and organic carbon need are the key factors to reduce wastewater treatment costs and thereby, avoid eutrophication. Denitrifying PO43-- removal (DPR) process using nitrate instead of oxygen for PO43- uptake was started up in the sequencing batch reactor (SBR) at a nitrate dosing rate of 20-25 mg N L-1 d-1. Operation with a real municipal wastewater supplied with CH3COONa, K2HPO4 and KNO3 succeeded in the cultivation of biomass containing denitrifying polyphosphate accumulating organisms (DPAOs). The durations of SBR process anaerobic/anoxic/oxic cycles were 1.5 h, 3.5 h and 1 h, respectively. SBR operation resulted in a maximum PO43--P uptake of 17 mg PO43--P g-1 MLSS. The highest TN and PO43- removal efficiencies were observed during the first half of reactor operation at 77 (±10) % and 71 (±5) %, respectively. An average COD removal rate of 172 (±98) mg g-1 MLSS and a high average removal efficiency of 89 (±4) % were achieved. Nitrite effect with/without nitrate as DPR electron acceptor was investigated in batch-scale to show possibilities to use high nitrite and nitrate contents simultaneously as electron acceptors for the anoxic phosphate uptake. Nitrate attenuation against nitrite toxicity can be economically justified in full-scale treatment applications in which wastewater has a high nitrogen content. Nitrate attenuated nitrite toxicity (caused by nitrite content at 5-100 mg NO2--N L-1) when using supplemental additions of nitrate (at concentrations of 45-200 mg NO3--N L-1) in batch tests. Illumina sequencing emphasized that during biomass adaption microbial community changed by lowered aerobic cycle length and by lowered nitrate dosing towards representation of key DPAO/PAO- organisms, such as Candidatus Accumulibacter, Xanthomonadaceae, Comomonadaceae, Saprospiraceae and Rhodocyclaceae. This study showed that DPAO biomass adaption to nitrate maintained an efficient COD, nitrogen and phosphorus removal and the biomass can be applied for treatment of wastewater containing high nitrite and nitrate content.

Strategies and relative mechanisms to attenuate the bioaccumulation and biotoxicity of ceria nanoparticles in wastewater biofilms.

Inhibitory effects of ceria nanoparticles (CeO2 NPs) on biofilm were investigated individually and in combination with phosphate (P), ethylene diamine tetraacetic acid (EDTA), humic acid (HA) and citrate (CA) to further explore the toxicity alleviating solutions. Exposure to 20 mg/L CeO2 NPs significantly decreased the performance of biofilm in nutrients removal. Distribution experiments suggested >98% of the CeO2 NPs retained in microbial aggregates, leading to 51.26 µg/L Ce ions dissolution. The dissolved CeIV and its further being reduced to CeIII stimulated the formation of O2- and OH, which increased lipid peroxidation level to 130.93% in biofilms. However, P/EDTA/CA captured or precipitated Ce ions, whereas EDTA/HA/CA shielded NPs-bacteria direct contacts, both disturbing the NPs adsorption, intercepting the redox transition between CeIV and CeIII, reducing the generation of O2- and OH, thus mitigating the toxicity of CeO2 NPs. These results illustrate the main drivers of CeO2 NPs biotoxicity and provide safer-by-design strategies.

Humic acid attenuation of silver nanoparticle toxicity by ion complexation and the formation of a Ag3+ coating.

The use of silver nanoparticles (AgNPs) result in an inevitable contact with aquatic environments. Here we study the behavior of AgNPs and the developmental toxicity in zebrafish embryos exposed to these nanoparticles (0-10 mg/L) with and without the presence of HA (20 mg/L), using zebrafish facility water (ZFW) and zebrafish growing media (ZGM). The presence of cations and HA gave rise to a decrease in Ag ion release and ζ-potential, an increase in the hydrodynamic diameter and oxidation of the AgNP surface. The results show that the presence of HA and cations in the media, as well as the silver speciation, i.e., the unusual presence of Ag3+, decreases the toxicity of AgNPs (LC50AgNPs: 1.19 mg/L; LC50AgNPs + HA: 3.56 mg/L), as well as silver bioavailability and toxicity in zebrafish embryos. Developmental alterations and the LC50 (1.19 mg/L) of AgNPs in ZFW were more relevant (p ≤ 0.05) than for AgNPs in ZGM (LC50 ˃ 10 mg/L). It was demonstrated that the bioaccumulation and toxicity of AgNPs depends on several factors including AgNPs concentration, nanoparticle aggregation, dissolved silver ions, speciation of silver ions, the amount of salt in the environment, the presence of humic substances and others, and different combinations of all of these factors.

Elemental copper nanoparticle toxicity to anaerobic ammonium oxidation and the influence of ethylene diamine-tetra acetic acid (EDTA) on copper toxicity.

Soluble ions released by elemental copper nanoparticles (Cu0 NP) are toxic to key microorganisms of wastewater treatment processes. However, their toxicity to anaerobic ammonium oxidation (anammox) has not yet been studied. Chelating agents occurring in wastewater may decrease copper ions (Cu2+) concentration and consequently, decrease copper toxicity. This study evaluated Cu0 NP and CuCl2 toxicity to anammox and the influence of ethylene diamine-tetra acetic acid (EDTA) on copper toxicity. Bioassays were supplemented with Cu0 NP or CuCl2 with and without EDTA. Anammox activities were used to calculate inhibition constants (Ki). Results showed that Cu0 NP are toxic to anammox. Ki constants with respect to added copper were 1.8- and 2.81-fold larger (less toxic) in EDTA-containing assays for Cu0 NP and CuCl2, respectively, compared to EDTA-free assays. Additionally, Ki constants calculated in EDTA-free assays with respect the measured dissolved copper concentration were 0.023 mM Cu0 NP and 0.014 mM CuCl2. The similarity of these Ki constants indicates that Cu0 NP toxicity to anammox is caused by the release of Cu2+. Finally, severe toxicity caused by 0.315 mM and Cu0 NP 0.118 mM CuCl2 was attenuated by 88-100% when 0.14 mM EDTA was supplied. Toxicity attenuation likely occurred because EDTA complexed Cu2+ ions, thus, decreasing their bioavailability. Overall, this study indicates that Cu0 NP and CuCl2 are toxic to anammox, and furthermore, that EDTA attenuates Cu0 NP and CuCl2 toxicity to anammox by complexing Cu2+ ions.

Metabolic transformation and attenuation characteristics of endogenous alkaloid toxic components of Tibetan medicinal herbs:a review / 中国药理学与毒理学杂志

The active ingredients in some Tibetan medicinal herbs are toxic components as well,and we need to have a clear understanding of their mechanism and metabolic pathways in use. The endogenous toxic components of highly toxic Tibetan herbal medicines are mainly alkaloids, such as aconitum alkaloids, methyllycaconitine, tropane alkaloids, brucine, strychnine, papaverine and swainso-nine. The majority of endogenous toxic alkaloids in Tibetan medicine herbs exist in roots, fruits and seeds of plants, exerting neurotoxicity or cardiotoxicity as highly toxic inherent chemicals. Most alka-loids are metabolized in phaseⅠvia de-alkylation, hydroxylation, hydrolysis and other reactions, as well as in phaseⅡvia glucuronic acid and sulfonic acid conjugation. They form various metabolites with high polarities and reduced toxicities so as to be easily excreted. The closeness between the therapeutic dose and toxic dose of alkaloids components in Tibetan medicinal herbs leads to their attenuated prep-aration via frying, dairy, highland barley wine soaking, or in combination with Terminalia Chebula to decrease toxicity, as is cited classic books on in Tebitan medicine. Focused on twelve alkaloids of five classes including aconitine, tropane and brucine, we have reviewed the characteristics of their metabo-lism and transformation, as well as their toxicity attenuation and safety evaluation.

Iron sulfide attenuates the methanogenic toxicity of elemental copper and zinc oxide nanoparticles and their soluble metal ion analogs.

Elemental copper (Cu(0)) and zinc oxide (ZnO) nanoparticle (NP) toxicity to methanogens has been attributed to the release of soluble metal ions. Iron sulfide (FeS) partially controls the soluble concentration of heavy metals and their toxicity in aquatic environments. Heavy metals displace the Fe from FeS forming poorly soluble metal sulfides in the FeS matrix. Therefore, FeS may be expected to attenuate the NP toxicity. This work assessed FeS as an attenuator of the methanogenic toxicity of Cu(0) and ZnO NPs and their soluble salt analogs. The toxicity attenuation capacity of fine (25-75µm) and coarse (500 to 1200µm) preparations of FeS (FeS-f and FeS-c respectively) was tested in the presence of highly inhibitory concentrations of CuCl2, ZnCl2 Cu(0) and ZnO NPs. FeS-f attenuated methanogenic toxicity better than FeS-c. The results revealed that 2.5× less FeS-f than FeS-c was required to recover the methanogenic activity to 50% (activity normalized to uninhibited controls). The results also indicated that a molar FeS-f/Cu(0) NP, FeS-f/ZnO NP, FeS-f/ZnCl2, and FeS-f/CuCl2 ratio of 2.14, 2.14, 4.28, and 8.56 respectively, was necessary to recover the methanogenic activity to >75%. Displacement experiments demonstrated that CuCl2 and ZnCl2 partially displaced Fe from FeS. As a whole, the results indicate that not all the sulfide in FeS was readily available to react with the soluble Cu and Zn ions which may explain the need for a large stoichiometric excess of FeS to highly attenuate Cu and Zn toxicity. Overall, this study provides evidence that FeS attenuates the toxicity caused by Cu(0) and ZnO NPs and their soluble ion analogs to methanogens.

[¹H-NMR-based metabonomics on chemical component groups with toxicity alleviation effect to Realgar in Niuhuang Jiedu tablet].

To study the chemical component groups with toxicity alleviation effect to Realgar in Niuhuang Jiedu tablet based on ¹H-NMR metabonomics. Twenty-four male Wistar rats were divided into four groups： control group, R group (treated with Realgar), RRSPG group (treated with Realgar, the root and rhizoma of Rheum palmatum, the root of Scutellaria baicalensis, the root of Platycodon grandiflorum and the root and rhizoma of Glycyrrhiza uralensis) and RC group (treated with total anthraquinones from the root and rhizoma of R. palmatum, total flavonoids from the root of S. baicalensis, total saponins from the root of P. grandiflorum, total flavonoids and saponins from the root and rhizoma of G. uralensis). Based on ¹H-NMR spectra of urine and serum from rats, PLS-DA was performed to identify different metabolic profiles.The metabolic profiles of R group were different from that of control group, while the metabolic profiles of RC group were almost similar to control group.Total anthraquinones from the root and rhizoma of R. palmatum, total flavonoids from the root of S. baicalensis, total saponins from the root of P. grandiflorum, total flavonoids and saponins from the root and rhizoma of G. uralensis regulated energy, choline and amino acid metabolism and gut flora disorder affected by realgar's toxicity.

¹H-NMR-based metabonomics on chemical component groups with toxicity alleviation effect to Realgar in Niuhuang Jiedu tablet / 中国中药杂志

To study the chemical component groups with toxicity alleviation effect to Realgar in Niuhuang Jiedu tablet based on ¹H-NMR metabonomics. Twenty-four male Wistar rats were divided into four groups： control group, R group (treated with Realgar), RRSPG group (treated with Realgar, the root and rhizoma of Rheum palmatum, the root of Scutellaria baicalensis, the root of Platycodon grandiflorum and the root and rhizoma of Glycyrrhiza uralensis) and RC group (treated with total anthraquinones from the root and rhizoma of R. palmatum, total flavonoids from the root of S. baicalensis, total saponins from the root of P. grandiflorum, total flavonoids and saponins from the root and rhizoma of G. uralensis). Based on ¹H-NMR spectra of urine and serum from rats, PLS-DA was performed to identify different metabolic profiles.The metabolic profiles of R group were different from that of control group, while the metabolic profiles of RC group were almost similar to control group.Total anthraquinones from the root and rhizoma of R. palmatum, total flavonoids from the root of S. baicalensis, total saponins from the root of P. grandiflorum, total flavonoids and saponins from the root and rhizoma of G. uralensis regulated energy, choline and amino acid metabolism and gut flora disorder affected by realgar's toxicity.