Activity of the enzymes of the antioxidative system in cadmium-treated Oxya chinensis (Orthoptera Acridoidae)

One purpose in this research was to determine the toxic effects of Cd on antioxidant enzymes of Oxya chinensis (Orthoptera: Acridoidae). Changes in the activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and guaiacol peroxidase (GPx) were measured in O. chinensis insects injected with Cd²⁺. Fifth-nymphs of O. chinensis insects were injected with Cd²⁺ at different concentrations (0, 0.55 × 10⁻⁴, 1.10 × 10⁻⁴, 1.65 × 10⁻⁴, 2.20 × 10⁻⁴, and 2.75 × 10⁻⁴ g g⁻¹). An increase in SOD activity in O. chinensis was observed at 1.10 × 10⁻⁴ to 2.75 × 10⁻⁴ g g⁻¹ Cd²⁺. The SOD activity was lower at 2.20 × 10⁻⁴and 2.75 × 10⁻⁴ g g⁻¹ than that at 1.10 × 10⁻⁴ and 1.65 × 10⁻⁴ g g⁻¹. It appears that SOD had a positive protective effect at low Cd²⁺ concentrations, and that this effect disappeared at high Cd²⁺ concentrations. CAT activity was accelerated to varying degrees at 1.10 × 10⁻⁴ to 2.75 × 10⁻⁴ g g⁻¹ for males and at 1.10 × 10⁻⁴, 2.20 × 10⁻⁴, and 2.75 × 10⁻⁴g g⁻¹ for females. CAT showed a strong detoxification effect with all treatments. GPx activity decreased with increasing Cd²⁺ concentration with all treatments for males and at 2.20 × 10⁻⁴ and 2.65 × 10⁻⁴g g⁻¹ for females. We showed that GPx activity had a weak detoxification function with all treatments for males and at high Cd²⁺ for females. Thus, CAT had a strong detoxification effect, whereas SOD had a medium and GPx had a weak detoxification effect. Among the three enzymes, CAT played an important role in the damaging mechanisms of reactive oxygen species in O. chinensis insects. Alterations of the antioxidant enzyme level under environmental stresses are suggested as indicators of biotic and abiotic stress.     

Silver nanoparticle induced toxicity to human sperm by increasing ROS(reactive oxygen species) production and DNA damage

Silver nanoparticles (AgNPs) have been used in medical products and industrial coatings, due to their antimicrobial properties. Excessive use of AgNPs can have adverse effects on the human body, however, their toxicity characteristics to human sperm and the potential mechanisms are not entirely clear. In this study, we exposed human sperm to different doses of AgNPs (0, 50 μg ml⁻¹, 100 μg ml⁻¹, 200 μg ml⁻¹ or 400 μg ml⁻¹) for various times (15 min, 30 min, or 60 min), followed by analyses of the sperm viability, motility and the ratio of abnormal to normal sperm.Then, transmission electron microscopy(TEM) was used to explore the sperm ultrastructural characteristics. Reactive oxygen species production and DNA fragmentation were tested using standard kits and the sperm chromatin dispersion method, respectively. The results showed a dose- and time-dependent decline in sperm viability and motility and an increased ratio of abnormal to normal sperm after 30 min and 60 min of exposure to AgNPs at 200 μg ml⁻¹ and 400 μg ml⁻¹. The most common abnormalities were sperm heads with disrupted chromatin or absent acrosomes, bent tails, and curved mid-pieces. The ultrastructural characteristics of AgNP-treated sperm included disrupted, swollen, granular and vacuolar defects of the chromatin. In addition, ROS(reactive oxygen species)production and DNA fragmentation were markedly increased after 60 min of exposure to AgNPs at 200 μg ml⁻¹ and 400 μg ml⁻¹. Our results indicated that AgNPs caused detrimental changes in human sperm characteristics, and the excessive use of AgNPs should be carried out with caution.     

Human health risk assessment and dietary intake of organochlorine pesticides through air,soil and food crops (wheat and rice) along two tributaries of river Chenab,Pakistan

To assess the organochlorine pesticides (OCPs) contamination and their probable hazardous effects on human health; cereal crops (wheat and rice; n = 28) agricultural soil (n = 28) and air (n = 6) samples were collected from Gujranwala division, Punjab Province, Pakistan. ∑OCPs concentration ranged between 123 and 635 pg m⁻³, 31 and 365 ng g⁻¹ (dw), 2.72 and 36.6 ng g⁻¹ (dw), 0.55 and 15.2 ng g⁻¹ (dw) for air, soil, rice and wheat samples, respectively. DDTs were the predominant over other OCPSs detected from screened samples while the source apportionment analysis suggested the new inputs of DDTs in the study area. EDI (estimated daily intake) of ∑OCPs through rice and wheat was found 39 and 40 ng kg⁻¹ day⁻¹, respectively. Hazard ratios (HRs) on the basis 95th percentile concentrations were exceeding the integrity for most of the investigated OCP in rice and wheat. The results revealed that there is a severe risk to the human population of the study area through consumption of contaminated cereal crops.     

In vivo effects of deoxynivalenol (DON) on innate immune responses of carp (Cyprinus carpio L.)

Deoxynivalenol (DON) is one of the most important members of Fusarium toxins since it often can be found in relevant concentrations in animal feeds. The effects of this group of toxins on fish are mostly unknown. The present study shows results from a feeding trial with carp (Cyprinus carpio L.) using three different concentrations of DON (352 μg kg⁻¹, 619 μg kg⁻¹, and 953 μg kg⁻¹ final feed, respectively) which are comparable to levels found in commercial fish feeds. Effects on growth and mass of fish were not observed during this 6 weeks lasting experiment. Only marginal DON concentrations were found in muscle and plasma samples. Blood parameters were not influenced although smaller erythrocytes occurred in fish treated with 352 μg kg⁻¹ DON. Analysis of antioxidative enzymes in erythrocytes showed increased superoxid dismutase and catalase activities in fish fed the low-dose feed. Immunosuppressive effects of DON were confirmed whereby cytotoxic effects on immune cells only partly explained the impairment of innate immune responses. Exact polarization of the immune system into pro-inflammatory or anti-inflammatory responses due to DON exposure should be clarified in further experiments, especially since the current results raise concern about impaired immune function in fish raised in aquaculture.     

Toxicological effects of clofibric acid and diclofenac on plasma thyroid hormones of an Indian major carp,Cirrhinus mrigala during short and long-term exposures

In the present investigation, the toxicity of most commonly detected pharmaceuticals in the aquatic environment namely clofibric acid (CA) and diclofenac (DCF) was investigated in an Indian major carp Cirrhinus mrigala. Fingerlings of C. mrigala were exposed to different concentrations (1, 10 and 100 μg L⁻¹) of CA and DCF for a period of 96 h (short term) and 35 days (long term). The toxic effects of CA and DCF on thyroid hormones (THs) such as thyroid stimulating hormone (TSH), thyroxine (T₄) and triiodothyronine (T₃) levels were evaluated. During the short and long-term exposure period TSH level was found to be decreased at all concentrations of CA (except at the end of 14^th day in 1 and 10 μg L^−l and 21^st day in 1 μg L^−l) whereas in DCF exposed fish TSH level was found to be increased when compared to control groups. T₄ level was found to be decreased at 1 and 100 μg L^−l of CA exposure at the end of 96 h. However, T₄ level was decreased at all concentrations of CA and DCF during long-term (35 days) exposure period. Fish exposed to all concentrations of CA and DCF had lower level of T₃ in both the treatments. These results suggest that both CA and DCF drugs induced significant changes (P < 0.01 and P < 0.05) on thyroid hormonal levels of C. mrigala. The alterations of these hormonal levels can be used as potential biomarkers in monitoring of pharmaceutical drugs in aquatic organisms.     

Urinary analysis reveals high deoxynivalenol exposure in pregnant women from Croatia

In this pilot survey the levels of various mycotoxin biomarkers were determined in third trimester pregnant women from eastern Croatia. First void urine samples were collected and analysed using a “dilute and shoot” LC–ESI–MS/MS multi biomarker method. Deoxynivalenol (DON) and its metabolites: deoxynivalenol-15-glucuronide and deoxynivalenol-3-glucuronide were detected in 97.5% of the studied samples, partly at exceptionally high levels, while ochratoxin A was found in 10% of the samples. DON exposure was primarily reflected by the presence of deoxynivalenol-15-glucuronide with a mean concentration of 120 μg L⁻¹, while free DON was detected with a mean concentration of 18.3 μg L⁻¹. Several highly contaminated urine samples contained a third DON conjugate, tentatively identified as deoxynivalenol-7-glucuronide by MS/MS scans. The levels of urinary DON and its metabolites measured in this study are the highest ever reported, and 48% of subjects were estimated to exceed the provisional maximum tolerable daily intake (1 μg kg⁻¹ b.w.).     

Influence of the method of production of eggs on the daily intake of polycyclic aromatic hydrocarbons and organochlorine contaminants: An independent study in the Canary Islands (Spain)

Analysis of 16 polycyclic aromatic hydrocarbons (PAHs), 20 organochlorine pesticides (OCPs) and 18 polychlorinated biphenyls (PCBs) were performed on eggs from three different production types (conventional, free-run and organic) collected from the markets of the Canary Islands (Spain). Unlike other studies we did not found differences in the content of PCBs or OCPs of eggs in relation to its production type. Median ∑OCPs content was 3.87 ng g⁻¹ fat, being dieldrin, dicofol, hexachlorobenzene, p,p′-DDE and p,p′-DDT the most frequently detected. Median ∑PCBs value was 3.93 ng g⁻¹ fat, with 79.9% of this amount coming from the marker PCBs. Two samples, one free-run and one organic, greatly exceeded the current European Commission (EC) limit of 2.5 pg TEQ_PCDD/F g⁻¹ lipid, but the rest were well below of this limit. The concentrations of PAHs in conventionally produced eggs were almost 4 times higher than in free-run or organic eggs. Mean dietary intake estimates of the organochlorine contaminants based on consumption of eggs, regardless of the type chosen, is negligible for the Canary Islands’ population. However, the median dietary intake estimates of PAHs greatly depend on the type of eggs chosen, being much lower when free-run and organic eggs are consumed.     

CYP-450 isoenzymes catalyze the generation of hazardous aromatic amines after reaction with the azo dye Sudan III

This work describes the mutagenic response of Sudan III, an adulterant food dye, using Salmonella typhimurium assay and the generation of hazardous aromatic amines after different oxidation methods of this azo dye. For that, we used metabolic activation by S9, catalytic oxidation by ironporphyrin and electrochemistry oxidation in order to simulate endogenous oxidation conditions. The oxidation reactions promoted discoloration from 65% to 95% of Sudan III at 1 × 10⁻⁴ mol L⁻¹ and generation of 7.6 × 10⁻⁷ mol L⁻¹ to 0.31 × 10⁻⁴ mol L⁻¹ of aniline, o-anisidine, 2-methoxi-5-methylaniline, 4-aminobiphenyl, 4,4′-oxydianiline; 4,4′-diaminodiphenylmethane and 2,6-dimethylaniline. The results were confirmed by LC–MS–MS experiments. We also correlate the mutagenic effects of Sudan III using S. typhimurium with the strain TA1535 in the presence of exogenous metabolic activation (S9) with the metabolization products of this compound. Our findings clearly indicate that aromatic amines are formed due to oxidative reactions that can be promoted by hepatic cells, after the ingestion of Sudan III. Considering that, the use of azo compounds as food dyestuffs should be carefully controlled.     

Oxidative stress responses in zebrafish Danio rerio after subchronic exposure to atrazine

Atrazine is one of the most used pesticides all over the world and it is frequently detected in surface water. The aim of this study was to investigate if zebrafish exposure to atrazine could induce oxidative stress and changes in detoxifying system. Juvenile fish were exposed to sublethal concentrations of 0.3, 3, 30, or 90 μg L⁻¹ for 28 days. The level of oxidized lipids increased in experimental groups exposed to atrazine at 30 and 90 μg L⁻¹ compared to control. Activity of glutathione S-transferase decreased in group with the highest concentration compared to control. A significant decline was observed in catalase activity in all experimental groups compared to control. Activity of superoxide dismutase increased only in experimental group exposed to atrazine at 30 μg L⁻¹ compared to control. Activity of glutathione peroxidase and reductase (GR) increased in experimental groups exposed to atrazine at 0.3 (only for GR activity) and 90 μg L⁻¹ compared to control. Our results showed that atrazine exposure had profound influence on the oxidative stress markers and detoxifying enzyme of the exposed zebrafish. The changes in antioxidant enzyme activities could be an adaptive response to protect the fish from the atrazine-induced toxicity.     

Ecotoxicity of veterinary enrofloxacin and ciprofloxacin antibiotics on anuran amphibian larvae

The ecological risks posed by two β-diketone antibiotics (DKAs, enrofloxacin, ENR and ciprofloxacin, CPX), characterized by their long persistence in aqueous environments and known deleterious effect on model organisms such as zebrafish were analysed using Rhinella arenarum larvae. Sublethal tests were conducted using environmentally relevant concentrations of both ENR and CPX (1–1000 μg L⁻¹) under standard laboratory conditions for 96 h. Biological endpoints and biomarkers evaluated were body size, shape, development and growth rates, and antioxidant enzymes (glutathione-S-transferase, GST; Catalase, CAT). Risk assessment was analysed based on ration quotients (RQ). The size and shape measurements of the larvae exposed to concentrations greater than 10 μg L⁻¹ of CPX were lower compared to controls (Dunnett post hoc p < 0.05) and presented signs of emaciation. Concentrations of 1000 μg L⁻¹of CPX induced GST activity, in contrast with inhibited GST and CAT of larvae exposed to ENR. Risk assessments indicated that concentrations greater than or equal to10 μg L⁻¹ of CPX and ENR are ecotoxic for development, growth, detoxifying, and oxidative stress enzymes. It is suggested that additional risk assessments may provide evidence of bioaccumulation of CPX and ENR in tissues or organs of amphibian larvae by mesocosm sediment test conditions. Finally, intestinal microbiome studies should be considered to establish the mechanisms of action of both antibiotics.     

Sustainable succinic acid production from rice husks

In this study, an investigation was carried out into the production of succinic acid by Actinobacillus succinogenes using the residual biomass rice husks as a sustainable carbon source. The rice husks were submitted to acid hydrolysis in autoclave and in a pressurized polytetrafluorethylene vessel. The hydrolysis conditions were optimized with the aid of a factorial design. The best results were obtained with a pressurized reactor using HCl 2.2% (v v^?1), at a temperature of 174 °C (59 bar), 46 min reaction time, and producing 19.0 g L^?1 glucose and 3.01 g L^?1 xylose. The hydrolysate was detoxified through a combination of pH regulation and adsorption on active carbon; it was subsequently, fermented in anaerobic medium at 37 °C; the nutrient concentration and the agitation speed were also optimized by factorial design. After 54 h static fermentation of the rice husks hydrolysate, supplemented with 8.40 g L^?1 yeast extract and 1.40 g L^?1 NaHCO₃, an amount of 12.5 g succinic acid L^?1 was produced, which corresponds to a yield of 59.9%. This confirms that, rice husks can definitely be used as substrate to produce succinic acid and other priority chemicals     

An analysis method for flavan-3-ols using high performance liquid chromatography coupled with a fluorescence detector

Procyanidins belong to a family of flavan-3-ols, which consist of monomers, (+)-catechin and (−)-epicatechin, and their oligomers and polymers, and are distributed in many plant-derived foods. Procyanidins are reported to have many beneficial physiological activities, such as antihypertensive and anticancer effects. However, the bioavailability of procyanidins is not well understood owing to a lack of convenient and high-sensitive analysis methods. The aim of this study was to develop an improved method for determining procyanidin content in both food materials and biological samples. High performance liquid chromatography (HPLC) coupled with a fluorescence detector was used in this study. The limits of detection (LODs) of (+)-catechin, (−)-epicatechin, procyanidin B2, procyanidin C1, and cinnamtannin A2 were 3.0 × 10⁻³ ng, 4.0 × 10⁻³ ng, 14.0 × 10⁻³ ng, 18.5 × 10⁻³ ng, and 23.0 × 10⁻³ ng, respectively; the limits of quantification (LOQs) were 10.0 × 10⁻³ ng, 29.0 × 10⁻³ ng, 28.5 × 10⁻³ ng, 54.1 × 10⁻³ ng, and 115.0 × 10⁻³ ng, respectively. The LOD and LOQ values indicated that the sensitivity of the fluorescence detector method was around 1000 times higher than that of conventional HPLC coupled with a UV-detector. We applied the developed method to measure procyanidins in black soybean seed coat extract (BE) prepared from soybeans grown under three different fertilization conditions, namely, conventional farming, basal manure application, and intertillage. The amount of flavan-3-ols in these BEs decreased in the order intertillage > basal manure application > conventional farming. Commercially available BE was orally administered to mice at a dose of 250 mg/kg body weight, and we measured the blood flavan-3-ol content. Data from plasma analysis indicated that up to the tetramer oligomerization, procyanidins were detectable and flavan-3-ols mainly existed in conjugated forms in the plasma. In conclusion, we developed a highly sensitive and convenient analytical method for the analysis of flavan-3-ols, and applied this technique to investigate the bioavailability of flavan-3-ols in biological samples and to measure flavan-3-ol content in food material and plants.     

Industrial release of fluoroquinolones (FQs) in the waste water bodies with their associated ecological risk in Pakistan

The unchecked production and use of fluoroquinolones (FQs) for the treatment of infections in human and livestock has increased in Pakistan, which resulted in large amount of antibiotics in water bodies. In the current study, the prevalence and associated ecological risk of three FQs were investigated in waste-water bodies and sludge samples of Kahuta and Hattar industrial zones. The average concentrations of ciprofloxacin (CIP), enrofloxacin (ENR) and levofloxacin (LEV) in the waste-water samples were slightly higher in Kahuta (i.e. 58, 32.9, and 36.7 μg L⁻¹ respectively), than those in Hattar sites (i.e. 42.1, 41.2, and 48.9 μg L⁻¹ respectively). However, the concentrations of CIP, ENR and LEV in the sludge samples were significantly higher (i.e. 159; 153 and 164 μg kg⁻¹ respectively) in Hattar sites, compared to those in Kahuta sites (i.e. 129, 58 and 91 μg kg⁻¹ respectively). The uses of FQs in the health sector resulted in water pollution and poses the ecological risk to aquatic organisms. The individual risk associated with CIP was highest in Kahuta industrial sites for green algae ranging (2900–9100) followed by M. aeruginosa (5800–18200), cyanobacteria (580–18204) and invertebrates (24.2–75.8). These values suggested that the prevalence of antibiotics in the waste-disposal sites could be potential risk for the aquatic ecosystem, and harmful to biodiversity.     

Influence of experimentally induced fever on the disposition of cefpirome in buffalo calves

The influence of Escherichia coli endotoxin-induced fever on the disposition of cefpirome was investigated in five male buffalo calves following a single intravenous dose of 10 mg kg⁻¹. Blood samples were collected from 1 min to 24 h of drug administration. The drug concentration in plasma was estimated by microbiological assay using E. coli as a test organism. The disposition of cefpirome followed two-compartment open model and the drug was detected above the minimum inhibitory concentration in plasma up to 12 h. The Vd_area and AUC were 0.75 ± 0.01 L kg⁻¹ and 35.1 ± 0.46 μg ml⁻¹ h, respectively. The elimination half-life of 1.81 ± 0.009 h and Cl_B of 0.29 ± 0.004 L kg⁻¹ h⁻¹ reflected rapid elimination and body clearance of cefpirome in febrile buffalo calves. Based on the results, a satisfactory dosage regimen of cefpirome in febrile buffalo calves was calculated to be 6 mg kg⁻¹ to be repeated at 8 h intervals.     

Protective effect of cinnamon polyphenols against STZ-diabetic mice fed high-sugar,high-fat diet and its underlying mechanism

This study was designed to investigate the potential effects of 14 days’ intragastrically given of cinnamon polyphenols (CPS) in treating diabetic mice induced by intraperitoneal injection of streptozotocin (150 mg kg⁻¹) and fed high-sugar, high-fat diet. The diabetic mice model was successfully established through determining on fasting blood-glucose (FBG) test. As revealed by glucose oxidase (GOD) and radioimmunoassay (RIA), both dimethyldiguanide (DC, 0.6 g kg⁻¹ d⁻¹) and CPS (0.3, 0.6, 1.2 g kg⁻¹ d⁻¹) treatments significantly resulted in down-regulation of blood glucose and insulin levels in serum, while the levels of oxidative stress markers were markedly lowered through ELISA assay. Meanwhile, the pathological damage in islet with pancreatic beta cells was ameliorated by treatment of CPS at different doses, as shown in HE stain. At the same time, the treatments also caused notable reduction of iNOS, NF-κB expressions showing in Western blot analysis. These findings demonstrate that cinnamon polyphenols can exert the hypoglycemic and hypolipidemic effects through the mechanisms that may be associated with repairing pancreatic beta cells in diabetic mice and improving its anti-oxidative capacity, as well as attenuating cytotoxicity via inhibition of iNOS, NF-κB activation.     

Occurrence and exposure to polycyclic aromatic hydrocarbons in kindling-free-charcoal grilled meat products in Taiwan

This study aimed to determine the contents of 16 PAHs in kindling-free-charcoal grilled meat and seafood products by GC–MS coupled with a QuEChERS method, and estimate the potential risk associated with consumption of those products in Taiwan. Results showed that the total PAHs contents ranged from 6.3 ± 0.9 to 238.8 ± 8.3 ng/g in poultry meat, 0.1 ± 0.0–547.5 ± 12.2 ng/g in red meat, and 6.6 ± 1.4–249.7 ± 6.4 ng/g in seafood products. Among various PAHs, the highly carcinogenic benzo[a]pyrene was detected in chicken breast grilled at 84 °C (30 min), chicken heart at 100 °C (26 min), chicken drumstick at 74 °C (20 min), duck drumstick at 85 °C (40 min), and lamb steak at 88 °C (12 min), with its level amounting to 1.3 ± 0.0, 2.4 ± 0.1, 4.0 ± 1.3, 3.1 ± 0.0, and 5.8 ± 0.5 ng/g, respectively. The generation of PAHs was associated with grilling time, temperature and fat content. Risk assessment of dietary exposure to PAHs revealed toxicity equivalent to range from ND – 6.174 ± 0.505 μg/g and margin of exposure was >10,000, which agreed with the EFSA’s definition of low public health concern. The lifelong average daily PAHs intake was higher for adults than for elderly people in Taiwan, however, consumption of kindling-free-charcoal grilled meat should not be a public health concern based on cancer risk potency.     

A higher frequency of CD4+ CXCR5+ T follicular helper cells in patients with newly diagnosed Henoch–Schönlein purpura nephritis

T follicular helper (TFH) cells play an important role in the humoral immune responses. The aim of this study was to examine the frequency of different subsets of CD4⁺ CXCR5⁺ TFH cells and B cells in patients with new-onset Henoch–Schönlein purpura nephritis (HSPN). The numbers of different subsets of CD4⁺ CXCR5⁺ TFH cells, B cells and the constituents of serum cytokines were detected in a total of 25 patients with newly diagnosed HSPN before and after treatment, and in 14 healthy controls (HC). The potential connection of these cells with the clinical characteristics in HSPN patients was analyzed. The numbers of circulating CD4⁺ CXCR5⁺, CD4⁺ CXCR5⁺ ICOS⁺ and CD4⁺ CXCR5⁺ PD-1⁺ TFH cells, CD86⁺ CD19⁺, CD38⁺ CD19⁺ B cells and serum IL-2, IL-4, IL-17A, IL-21 and IFN-γ were significantly higher in HSPN patients (p < 0.05) than in HC. Before and after treatment the numbers of CD4⁺ CXCR5⁺ TFH cells were negatively correlated with the values of eGFR (r = − 0.7162, p < 0.05; r = − 0.732, p < 0.05, respectively). Similarly the numbers of CD4⁺ CXCR5⁺ PD-1⁺ TFH cells were negatively correlated with 24-h urinary proteins (r = − 0.4013, p < 0.05; r = − 0.7857, p < 0.05, respectively), and the numbers of CD4⁺ CXCR5⁺ ICOS⁺ TFH cells were positively correlated with the levels of serum IL-21 (r = 0.5186, p < 0.05; r = 0.8503, p < 0.05, respectively) and 24-h urinary protein (r = 0.6045, p < 0.05; r = 0.833, p < 0.05, respectively) in these patients, regardless of treatment. Following treatment the numbers of CD4⁺ CXCR5⁺, CD4⁺ CXCR5⁺ PD-1⁺, and CD4⁺ CXCR5⁺ ICOS⁺ TFH cells, as well as serum levels of IL-21 were significantly reduced, however IL-4 levels were noticeably increased (p < 0.05). A higher frequency of circulating CD4⁺ CXCR5⁺ TFH cells existed in patients with HSPN and may be a viable therapeutic target.     

Toxicity of cylindrospermopsin in human lymphocytes: Proliferation,viability and cell cycle studies

The global expansion of cylindrospermopsin (CYN) producing cyanobacteria in surface freshwater increases the risk of human exposure and poisoning. Following ingestion, CYN is transported with blood in general circulation to the liver and kidneys, and can potentially interact with immune system cells. In the present study, we investigated whether CYN (0.01–1.0 μg ml⁻¹) can alter the function of human peripheral blood lymphocytes isolated from healthy donors. It was found that CYN demonstrates significant antiproliferative activity in lymphocytes during different phases of their activation. The most remarkable effects (decrease by > 90%) were observed in lymphocytes exposed to 1 μg ml⁻¹ CYN at the beginning of activation. Further analyses revealed a cell-cycle arrest at G0/G1 and prolonged S phase in lymphocytes undergoing activation and significant apoptosis inducement in activated cells. Reduced abilities to fight pathogenic microorganisms or malignant cells should be taken into consideration in CYN exposure and risk assessments.     

Down-regulation of carboxylesterases 1 and 2 plays an important role in prodrug metabolism in immunological liver injury rats

Liver plays a central role in xenobiotics metabolism, thus affecting the in vivo disposition and therapeutic effects of drugs. Carboxylesterases (CESs), with the main isoforms CES1 and CES2, are important in the metabolism of ester-type prodrugs. However, influences of immunological liver injury on the activity of CES remain undefined. In the present study, we demonstrated treatment with lipopolysaccharide (LPS) suppressed the activities of CES1 and CES2. The decreased activities of CES1 and CES2 were preliminarily assessed by the hydrolysis assay for their common substrate p-nitrophenyl acetate (PNPA) with rat hepatic microsomal enzyme. Subsequently, RT-PCR results showed that the levels of CES1 mRNA and mRNA of CES2 (AB010635) and CES2 (AY034877) in the model group were significantly lower than those of the normal control group (P < 0.05). Western blot results showed that the expressions of CES1 and CES2 proteins were decreased (P < 0.05). To further clarify the effects of LPS on the metabolic activities of CESs, pharmacokinetic studies were performed in rats by utilizing imidapril and irinotecan (CPT-11) as the specific substrates for CES1 and CES2, respectively. After treatment with LPS, AUC_0 -∞ and C_max of imidaprilat were decreased from 2084.86 ± 340.66 ng · h^− 1 · mL^− 1 and 234.66 ± 68.85 ng · mL^− 1 to 983.87 ± 315.34 ng · h^− 1 · mL^− 1 and 113.1 ± 19.69 ng · mL^− 1 (P < 0.05), respectively. Moreover, AUC_0 -∞ and C_max of SN-38 were decreased from 8100 ± 918.6 ng · h^− 1 · mL^− 1 and 144.67 ± 20.28 ng · mL^− 1 to 3270 ± 500.5 ng · h^− 1 · mL^− 1 and 56.19 ± 10.38 ng · mL^− 1 (P < 0.05), respectively. In summary, immunological liver injury remarkably attenuated the expressions and metabolic activities of CES1 and CES2, which may be associated with the regulatory effects of cytokines under inflammation.     

Evaluation of estrogenic activity in animal diets using in vitro assay

A yeast estrogen bioassay (RIKILT REA) was in-house validated for feed on the 5 μg 17β-estradiol-equivalents per kg level according to EC Decision 2002/657/EC. All the performance characteristics met the criteria as defined in the Decision and the REA is able to detect 17β-estradiol in animal feed at a low level of 1.15–2 μg kg⁻¹. Subsequently, the developed and validated procedure was applied to determine the estrogenic activity in 24 feed samples intended for food producing animals, pets and laboratory animals. Two batches of rodent diet Murigran and one dog feed have been presented as a suspect, i.e. gave responses above the determined decision limit (CCα) and detection capability (CCβ). In assessing the performance of the estrogenic activity in these diets evaluated by comparison with the 17β-estradiol calibration curve, 17β-estradiol-equivalence levels of 7.07 μg EEQ kg⁻¹ and 9.54 μg EEQ kg⁻¹ in two batches of rodent diet and 5.3 μg EEQ kg⁻¹ in dog feed have been established. The activities observed in the rodent feed could be explained by chemical analysis, revealing high amounts of genistein, daidzein and trace amounts of zearalenone. In addition, the estrogenic activity in one of rodent feed was above the established CCα, but below the CCβ values established and all other samples showed no estrogenic activity with responses below the CCα value, which corresponds to levels below 2 μg EEQ kg⁻¹.