Elucidating the toxicity mechanism of AFM2 and the protective role of quercetin in albino mice

Effect of formaldehyde exposure on phytochemical content and functional activity of Agaricus bisporus (Lge.) Sing

In this study, the effect of formaldehyde on phytochemical content and antioxidant activity of Agaricus bisporus was investigated. Synthetic compost based on wheat straw was prepared by fermentation and disinfection. After steam pasteurization, 5 g of A. bisporus mycelia were inoculated into 1 kg of compost. To determine the effects of formaldehyde, 2, 4, and 6% concentrations were added to the composts, while compost without formaldehyde was used for the control group. The harvesting period was set at 10 weeks. Total phenolic and flavonoid content, macro- and microelement profile, and phenolic content were analyzed in the harvested A. bisporus samples. Macro- and microelement content was determined by ICP-OES, and phenolic compound profile was determined by LC-MS/MS analysis. Formaldehyde levels in A. bisporus samples were determined by the acetylacetone spectrophotometry method. The antioxidant capacity of A. bisporus samples was determined by DPPH scavenging activity; antimutagenic effects of samples were determined by Allium test. Application of 2, 4, and 6% formaldehyde resulted in a 1.12-, 1.19-, and 2.07-fold reduction in total phenolic content, respectively. The total phenolic content was reduced between 34.4% and 71.8%. These changes were confirmed by LC-MS/MS analysis. Compounds such as protocatechuic acid, salicylic acid, ferulic acid, and 4-OH benzoic acid, which were detected in the control group, could not be detected in the samples treated with 6% formaldehyde, and it was found that the application of formaldehyde reduced the phenolic content. Similar changes were also observed in macro- and microelements, and significant changes in elemental contents were observed after formaldehyde application. While the presence of formaldehyde at a low level, which may be due to natural production, was detected in the control group, a residue of 11.41 ± 0.93 mg/kg was determined in the 6% FMD applied group. All these changes resulted in a decrease in the antioxidant activity of A. bisporus. The DPPH scavenging activity, which was determined in the range of 21.6-73.3% in the control samples, decreased to 12.3-56.7% in the samples treated with formaldehyde. These results indicate that the application of formaldehyde at different stages of A. bisporus cultivation leads to significant changes in the nutritional value and biological activity of A. bisporus.

Human CYP1A1-activated aneugenicity of aflatoxin B1 in mammalian cells and its combined effect with benzo(a)pyrene

Aflatoxin B1 (AFB1) is the most toxic mycotoxin and a proven human carcinogen that requires metabolic activation, known by cytochrome P450 (CYP) 1A2 and 3A4. Previous evidence showed that AFB1 is activated by human recombinant CYP1A1 expressed in budding yeast. Yet, the toxicity, in particular the genotoxicity of the reactive metabolites formed from AFB1 remains unclear. Humans could be exposed to both AFB1 and benzo(a)pyrene (BaP) simultaneously, thus we were interested in their combined genotoxic effects subsequent to metabolic activation by CYP1A1. In this study, molecular docking of AFB1 to human CYP1A1 indicated that AFB1 is valid as a substrate. In the incubations with AFB1 in human CYP1A1-expressed microsomes, AFM1 as a marking metabolite of AFB1 was detected. Moreover, AFB1 induced micronucleus formation in a Chinese hamster V79-derived cell line and in a human lung epithelial BEAS-2B cell line, both expressing recombinant human CYP1A1, V79-hCYP1A1 and 2B-hCYP1A1 cells, respectively. Immunofluorescence of centromere protein B stained micronuclei was dominant in AFB1-treated BEAS-2B cells exposed to AFB1, suggesting an aneugenic effect. Moreover, AFB1 elevated the levels of ROS, 8-OHdG, AFB1-DNA adduct, and DNA breaks in 2B-hCYP1A1 cells, compared with those in the parental BEAS-2B cells. Meanwhile, AFB1 increased CYP1A1, RAD51, and γ-H2AX protein levels in 2B-hCYP1A1 cells, which were attenuated by the CYP1A1 inhibitor bergamottin. Co-exposure of AFB1 with BaP increased 8-OHdG, RAD51, and γ-H2AX levels (indicating DNA damage). In conclusion, AFB1 could be activated by human CYP1A1 for potent aneugenicity, which may be further enhanced by co-exposure to BaP.

LC-MS/MS, GC-MS and molecular docking analysis for phytochemical fingerprint and bioactivity of Beta vulgaris L

The plants that we consume in our daily diet and use as a risk preventer against many diseases have many biological and pharmacological activities. In this study, the phytochemical fingerprint and biological activities of Beta vulgaris L. leaf extract, which are widely consumed in the Black Sea region, were investigated. The leaf parts of the plant were dried in an oven at 35 °C and then ground into powder. The main constituents in B. vulgaris were identified by LC-MS/MS and GC-MS analyses. Phenolic content, betaxanthin and betacyanin levels were investigated in the extracts obtained using three different solvents. The biological activity of the extract was investigated by anti-microbial, anti-mutagenic, anti-proliferative and anti-diabetic activity tests. Anti-diabetic activity was investigated by in vitro enzyme inhibition and in-silico molecular docking was performed to confirm this activity. In the LC-MS analysis of B. vulgaris extract, a major proportion of p_coumaric acid, vannilin, protecatechuic aldehyde and sesamol were detected, while the major essential oils determined by GC-MS analysis were hexahydrofarnesyl acetone and phytol. Among the solvents used, the highest extraction efficiency of 2.4% was obtained in methanol extraction, and 36.2 mg of GAE/g phenolic substance, 5.1 mg/L betacyanin and 4.05 mg/L betaxanthin were determined in the methanol extract. Beta vulgaris, which exhibited broad-spectrum anti-microbial activity by forming a zone of inhibition against all tested bacteria, exhibited anti-mutagenic activity in the range of 35.9-61.8% against various chromosomal abnormalities. Beta vulgaris extract, which did not exhibit mutagenic, sub-lethal or lethal effects, exhibited anti-proliferative activity by reducing proliferation in Allium root tip cells by 21.7%. 50 mg/mL B. vulgaris extract caused 58.9% and 55.9% inhibition of α-amylase and α-glucosidase activity, respectively. The interactions of coumaric acid, vanniline, hexahydrofarnesyl acetone and phytol, which are major compounds in phytochemical content, with α-amylase and α-glucosidase were investigated by in silico molecular docking and interactions between molecules via various amino acids were determined. Binding energies between the tested compounds and α-amylase were obtained in the range of - 4.3 kcal/mol and - 6.1 kcal/mol, while for α-glucosidase it was obtained in the range of - 3.7 kcal/mol and - 5.7 kcal/mol. The biological activities of B. vulgaris are closely related to the active compounds it contains, and therefore studies investigating the phytochemical contents of plants are very important. Safe and non-toxic plant extracts can help reduce the risk of various diseases, such as diabetes, and serve as an alternative or complement to current pharmaceutical practices.

Therapeutic detoxification of quercetin for aflatoxin B1-related toxicity: Roles of oxidative stress, inflammation, and metabolic enzymes

Aflatoxins (AFTs), a type of mycotoxin mainly produced by Aspergillus parasiticus and Aspergillus flavus, could be detected in food, feed, Chinese herbal medicine, grain crops and poses a great threat to public health security. Among them, aflatoxin B1 (AFB1) is the most toxic one. Exposure to AFB1 poses various health risks to both humans and animals, including the development of chronic inflammatory diseases, cardiovascular diseases, neurodegenerative diseases, and cancer. The molecular mechanisms underlying these risks are intricate and dependent on specific contexts. This review primarily focuses on summarizing the protective effects of quercetin, a natural phenolic compound, in mitigating the toxic effects induced by AFB1 in both in vitro experiments and animal models. Additionally, the review explores the molecular mechanisms that underlie these protective effects. Quercetin has been demonstrated to not only have the direct inhibitory action on the production of AFTs from Aspergillus, both also possess potent ameliorative effects against AFB1-induced cytotoxicity, hepatotoxicity, and neurotoxicity. These effects are attributed to the inhibition of oxidative stress, mitochondrial dysfunction, mitochondrial apoptotic pathway, and inflammatory response. It could also directly target several metabolic enzymes (i.e., CYP3As and GSTA1) to reduce the production of toxic metabolites of AFB1 within cells, then reduce AFB1-induced cytotoxicity. In conclusion, this review highlights quercetin is a promising detoxification agent for AFB1. By advancing our understanding of the protective mechanisms offered by quercetin, we aim to contribute to the development of effective detoxification agents against AFB1, ultimately promoting better health outcomes.

Self-assembly of maltose-albumin nanoparticles for efficient targeting delivery and therapy in liver cancer

The effective delivery and targeted release of drugs within tumor cells are critical factors in determining the therapeutic efficacy of nanomedicine. To achieve this objective, a conjugate of maltose (Mal) and bovine serum albumin (BSA) was synthesized by the Maillard reaction and self-assembled into nanoparticles with active-targeting capabilities upon pH/heating induction. This nanoparticle could be effectively loaded with doxorubicin (DOX) to form stable nanodrugs (Mal-BSA/DOX) that were sensitive to low pH or high glutathione (GSH), thereby achieving a rapid drug release (96.82 % within 24 h). In vitro cell experiments indicated that maltose-modified BSA particles efficiently enhance cellular internalization via glucose transporters (GLUT)-mediated endocytosis, resulting in increased intracellular DOX levels and heightened expression of γ-H2AX. Consequently, these results ultimately lead to selective tumor cells death, as evidenced by an IC50 value of 3.83 μg/mL in HepG2 cells compared to 5.87 μg/mL in 293t cells. The efficacy of Mal-BSA/DOX in tumor targeting therapy has been further confirmed by in vivo studies, as it effectively delivered a higher concentration of DOX to tumor tissue. This targeted delivery approach not only reduces the systemic toxicity of DOX but also effectively inhibits tumor growth (TGI, 75.95 %). These findings contribute valuable insights into the advancement of targeting-albumin nanomedicine and further support its potential in tumor treatment.

Evaluation of the influence of N-acetylcysteine and broccoli extract on systemic paraquat poisoning: Implications for biochemical, physiological, and histopathological parameters in rats

Objectives

Paraquat (PQ), a potent environmental herbicide, is recognized for inducing irreparable toxic damage to biological systems. This study aimed to evaluate the effectiveness of N-acetylcysteine (NAC) and broccoli extract, individually and in combination, in alleviating PQ poisoning in rats, leveraging the exceptional anti-oxidant, anti-inflammatory, and anti-apoptotic properties of broccoli.

Materials and Methods

Seventy Wistar rats were categorized into seven groups: C (control, vehicle), PQ (paraquat at 40 mg/kg), BC (broccoli extract at 300 mg/kg), NC (N-acetylcysteine at the same dose of 300 mg/kg), and combined groups PQ+BC, PQ+NC, and NC+PQ+BC, all administered equivalent doses. After 42 days, blood samples were collected to evaluate liver and kidney parameters, proinflammatory biomarkers, caspase-3, and caspase-9. Lung tissues were excised, with one part preserved for hydroxyproline and oxidative stress parameter measurement and another sectioned and stained for histopathological analysis.

Results

The PQ group exhibited the highest lung-to-body weight (LW/BW) ratio, while the PQ+BC+NC group demonstrated the lowest ratio. Results indicated an elevated lung hydroxyproline concentration and a significant reduction in anti-oxidant enzymes (catalase, glutathione peroxidase, superoxide dismutase, and total anti-oxidant capacity) (P<0.001). The PQ+BC group showed modified malondialdehyde levels, reaching a peak in the PQ group. Additionally, a significant decrease in tumor necrosis factor, interleukin-1, caspase-3, and caspase-9 was observed in the PQ+BC+NC group (P<0.01). Pulmonary edema, hyperemia, and severe hemorrhage observed in the PQ group were notably reduced in the PQ+BC+NC group.

Conclusion

The combination of active compounds from broccoli and NAC demonstrated significant systemic and pulmonary effects in mitigating PQ-induced toxicity.

Preventive effects of quercetin against inflammation and apoptosis in cyclophosphamide-induced testicular damage

Objectives

We aimed to investigate the effects of quercetin (QRC) against cyclophosphamide (CP)-induced testicular damage and how it interacts with apoptotic and inflammatory signaling pathways.

Materials and Methods

Forty male Wistar rats were randomly divided into four groups, 10 in each group; Control group (corn oil, intragastrically, 14 days), QRC group (100 mg/kg QRC, dissolved in corn oil, 14 days), CP group (200 mg/kg CP, intraperitoneally, single dose on the 7th day), and CP+QRC group (100 mg/kg QRC, intragastrically, 14 days and 200 mg/kg CP, intraperitoneally, single dose on the 7th day). Animals were sacrificed one day after the last QRC application and the effects of quercetin were evaluated by histological, morphometrical, and hormonal parameters. Also, nuclear factor kappa B (NFkB), nuclear factor erythroid 2 related factor 2 (Nrf2), Bcl-2 associated X protein (Bax), and B-cell lymphoma-2 (Bcl-2) immunoreactivities were evaluated immunohistochemically.

Results

CP increased the testicular weight/body weight ratio, significantly decreasing body weights and testicular weights. All hormone levels were also reduced significantly. Morphometrically, seminiferous tubules diameter and germinal epithelial thickness decreased, while a significant increase was determined in interstitial field width in addition to histological damage. Furthermore, immunohistochemical findings also indicated that NFkB and Bax immunoreactivity were increased in the CP group, whereas significant decrease was seen in Nrf2 and Bcl-2 immunoreactivity. Apoptotic cell and tubule index were reduced in CP. QRC ensured improvement in all findings.

Conclusion

Data showed us, that QRC may have preventive effects in CP-induced testicular damage by acting on NFkB, Nrf2, Bax, and Bcl-2 pathways.

Potential toxicity assessment of mycotoxin fusaric acid with the spectral shift profile on DNA

In this study, the multiple toxicities induced by three different doses (1, 5, and 10 μM) of fusaric acid (FA), a mycotoxin, was investigated with Allium test. Physiological (percent germination, root number, root length, and weight gain), cytogenetic (micronucleus = MN, chromosomal abnormalities = CAs, and mitotic index = MI), biochemical (proline level, malondialdehyde = MDA level, catalase = CAT activity, and superoxide dismutase = SOD activity), and anatomical parameters were used as indicators of toxicity. Allium cepa L. bulbs were divided into four groups as one control and three applications. The bulbs in the control group were germinated with tap water for 7 days, and the bulbs in the treatment groups were germinated with three different doses of FA for 7 days. As a result, FA exposure caused a decrease in all physiological parameters examined at all three doses. Besides, all FA doses caused a decrease in MI and an increase in the frequency of MN and the number of CAs. FA promoted CAs such as nucleus with vacuoles, nucleus buds, irregular mitosis, bridge, and misdirection in root meristem cells. DNA and FA interactions, which are the possible causes of genotoxic effects, were examined by spectral analysis, and FA could interact with DNA through intercalation, causing bathochromic and hypochromic shifts in the spectrum. FA also causes toxicity by inducing oxidative stress in cells, confirming this; dose-related increases in root MDA and proline levels were measured as a result of FA exposure. In the root SOD and CAT enzyme activities, increases up to 5 μM doses and decreases at 10 μM doses were measured. FA exposure induced anatomical damage such as necrosis, epidermis cell damage, flattened cell nucleus, thickening of the cortex cell wall, and unclear vascular tissue in root tip meristem cells. As a result, FA caused a comprehensive toxicity by showing an inhibitory effect in A. cepa test material, and the Allium test was a very useful test in determining this toxicity.