The Effects of Acute Bisphenol A Toxicity on the Hematological Parameters, Hematopoiesis, and Kidney Histology of Zebrafish (Danio rerio).

In this study, the results of evaluating the acute toxicity of Bisphenol A on Danio rerio are presented, encompassing peripheral blood parameters, the composition of hematopoietic cells of erythroid and myeloid lines in the head kidney, and data from histological studies. The LC50 values of Bisphenol A for adult zebrafish individuals for 12, 24, and 48-96 h were determined, which were 18.04, 7.55, and 6.22 mg/L, respectively. The study includes data on the morphology and quantitative frequency of specific cells in the hematopoietic tissue of the head kidney, along with the consideration of adaptive mechanisms in hematopoiesis under BPA exposure. The application of polynomial regression analysis to reveal the concentration-effect relationship for some hematological and histological parameters was demonstrated. Significant increases in the frequency of erythrocyte nuclear abnormalities were observed at BPA concentrations of 6 and 8 mg/L, which indicates a genotoxic effect. BPA's impact on fish peripheral blood parameters manifested as an increase in the number of erythrocytes (RBC) and immature erythrocytes, as well as a decrease in the number of lymphocytes. The most notable pathological changes in the head kidney's hematopoietic tissue included circulatory disturbances and the formation of inflammation/degradation foci, as confirmed by histopathologic indices. At BPA concentrations of 2 and 4 mg/L, the observed changes were compensated for by hematopoietic adaptation mechanisms; however, at concentrations of 6 and 8 mg/L, acute systemic toxicity was evident.

Ability of Lactobacillus brevis 47f to Alleviate the Toxic Effects of Imidacloprid Low Concentration on the Histological Parameters and Cytokine Profile of Zebrafish (Danio rerio).

In the present article, the possible mitigation of the toxic effect of imidacloprid low-concentration chronic exposure on Danio rerio by the probiotic strain Lactobacillus brevis 47f (1 × 108 CFU/g) was examined. It was found that even sublethal concentration (2500 µg/L) could lead to the death of some fish during the 60-day chronic experiment. However, the use of Lactobacillus brevis 47f partially reduced the toxic effects, resulting in an increased survival rate and a significant reduction of morphohistological lesions in the intestines and kidneys of Danio rerio. The kidneys were found to be the most susceptible organ to toxic exposure, showing significant disturbances. Calculation of the histopathological index, measurement of morphometric parameters, and analysis of principal components revealed the most significant parameters affected by the combined action of imidacloprid and Lactobacillus brevis 47f. This effect of imidacloprid and the probiotic strain had a multidirectional influence on various pro/anti-inflammatory cytokines (IL-1ß, TNF-α, IL-6, IL-8). Therefore, the results suggest the possibility of further studying the probiotic strain Lactobacillus brevis 47f as a strain that reduces the toxic effects of xenobiotics. Additionally, the study established the possibility of using imidacloprid as a model toxicant to assess the detoxification ability of probiotics on the kidney and gastrointestinal tract of fish.

Novel Extract from Beetle Ulomoides dermestoides: A Study of Composition and Antioxidant Activity.

A biologically active extract from the darkling beetle Ulomoides dermestoides was obtained using the electro-pulse plasma dynamic extraction method. The beetle water extract contained a complex of antioxidant substances such as antioxidant enzymes and nonprotein antioxidants, as well as a complex of heat shock antistress proteins. This determines the rather high antioxidant activity of the aqueous extract of the beetle, i.e., 1 mg of dry matter/mL of the extract has an equivalent antioxidant activity to 0.2 mM Trolox (a water-soluble analog of vitamin E). It was shown that the beetle extract can lead to a 25-30% increase in the average lifespan of nematode Caenorhabditiselegans, under normal conditions, and a 12-17% increase under conditions of oxidative stress (with paraquat), and significantly inhibits the fructosylation reaction of serum albumin. Therefore, the beetle aqueous extract shows promise as a biologically active complex exhibiting antioxidant activity.

Protective effects of Lactobacillus fermentum U-21 against paraquat-induced oxidative stress in Caenorhabditis elegans and mouse models.

The aims of this work were to identify in vivo manifestations of antioxidant activity of Lactobacillus strains isolated from healthy human biotopes and to show the possibility of protective action of the selected strain on the model of oxidative stress induced by paraquat in the model of early Parkinson's disease (PD) in mice. We studied the protective effects of 14 Lactobacillus strains belonging to five species on the lifespan of the soil nematode Caenorhabditis elegans experiencing oxidative stress induced by paraquat. The Lactobacillus strains used in this study were selected previously based on their ability to reduce oxidative stress in vitro. One of the strains that showed promising results on C. elegans was tested in a mouse model of PD in which C57/BL6 mice were injected regularly with paraquat. We assessed the state of their internal organs, the preservation of dopaminergic neurons in the substantia nigra as well as their motor coordination. The positive impact of Lactobacillus fermentum U-21 strain supplementation on paraquat treated animals was observed. L. fermentum U-21 strain reduced the toxicity of paraquat in C. elegans model: the lifespan of the soil nematode C. elegans was extended by 25%. L. fermentum U-21 protected the mice against anatomical and behavioral changes typical of PD: there were no changes in the coordination of movement and the preservation of dopaminergic neurons in the brain. Life span of the nematode C. elegans pre-grown on a lawn of E. coli OP50 + Lactobacillus under oxidative stress conditions; the concentration of the oxidizing agent paraquat in the S medium was 50 mmol l-1.

The Lactobacillus brevis 47 f Strain Protects the Murine Intestine from Enteropathy Induced by 5-Fluorouracil.

We report that the results of our study indicate that Lactobacillus brevis 47 f strain isolated from the faeces of a healthy individual prevents the manifestations of experimental mucositis induced by treatment of Balb/c mice with the anticancer drug 5-fluorouracil (5 FU; 100 mg/kg i.p. × 3 days). The presence of damage to the intestine and the colon was determined by a morphometric analysis of specimens including the height of villi, the amount of goblet cells and infiltrating mononuclear cells, and the expression of the proliferative Ki-67 antigen. Changes in the lipid peroxidation in the blood and the intestine were determined by severalfold increase of the concentration of malonic dialdehyde. Oral administration of L.brevis 47 f strain prior to 5 FU decreased the drug-induced morphological and biochemical changes to their respective physiological levels; the ability of intestinal epitheliocytes to express Ki-67 was partially restored. These effects of L.brevis 47 f strain were more pronounced or similar to those of the reference compound Rebamipid, a quinoline derivative known to protect the gut from drug-induced toxicity. Thus, the new lactobacilli strain attenuates the severity of 5 FU-induced enteropathy.

A bioluminescent test system reveals valuable antioxidant properties of lactobacillus strains from human microbiota.

Oxidative stress cause serious damages in human organism resulting in multiple diseases. Antioxidant therapy includes diet, the use of chemical agents or commensal bacteria such as lactobacilli. This study aims to evaluate the antioxidant (AO) activity of cell-free culture supernatants of lactobacilli, isolated from different parts of the human body. A test system based on Escherichia coli MG1655 strains carrying plasmids encoding luminescent biosensors pSoxS-lux and pKatG-lux inducible by superoxide anion and hydrogen peroxide, respectively, was used to analyze cell-free culture supernatants of lactobacilli. Bioluminescent detection systems are suitable for quick screening of AO activity of lactobacilli. The majority of strains (51 out of 81) belonging to six different species demonstrated various levels of antioxidant activity. This activity was confirmed using the trolox equivalent method. The genome of one of the strains showing high AO activity was sequenced, and the genes putatively involved in AO capacity were determined. Potencies of standard AO and CFS from the most active Lactobacillus strains. Percentages of decrease in the detected luminescence (IAO%) in the presence of AO or CFS are presented. L. br.-L. brevis, L. pl. -L. plantarum, L. rh.-L. rhamnosus.