Effects of developmental exposures to Bisphenol-A and Bisphenol-S on hepatocellular function in male Long-Evans rats

Derivation of the oral reference dose (RfD) for bisphenol S and bisphenol F based on epidemiological and experimental studies

With bisphenol A (BPA) restricted, its analogs are appearing frequently in the environment, raising health concerns. However, no reasonable threshold of toxicity has been established at the current international level for BPA analogs. The aim of this study was to derive oral reference doses (RfD) for two BPA substitutes, bisphenol S (BPS) and bisphenol F (BPF). A systematic search was conducted to screen epidemiologic and experimental rodent studies. Based on a thorough evaluation of those data, this study performed accurate model fitting using the Benchmark Dose Software (BMDS) to determine the recommended lower limit of the benchmark dose (BMDL) for BPS and BPF. Based on the dose-effect curves of the recommended models from BMDS, and incorporating the decline in male semen quality in epidemiologic studies as a critical effect, the present study further determined the departure point (POD) of BPS and BPF. After integrating uncertainty analysis, the RfD values of BPS and BPF were 0.37 and 8.09 ng/kg-bw/day, respectively, which were lower than the RfD value of BPA, but greater than the established minimum international toxicity thresholds of the tolerable daily intake of BPA. This study provides critical scientific evidence and important references for international environmental health regulatory agencies to improve their toxicity threshold settings, while emphasizing their increased attention to BPA alternatives.

Liver and Pancreatic Toxicity of Endocrine-Disruptive Chemicals: Focus on Mitochondrial Dysfunction and Oxidative Stress

In recent years, the worldwide epidemic of metabolic diseases, namely obesity, metabolic syndrome, diabetes and metabolic-associated fatty liver disease (MAFLD) has been strongly associated with constant exposure to endocrine-disruptive chemicals (EDCs), in particular, the ones able to disrupt various metabolic pathways. EDCs have a negative impact on several human tissues/systems, including metabolically active organs, such as the liver and pancreas. Among their deleterious effects, EDCs induce mitochondrial dysfunction and oxidative stress, which are also the major pathophysiological mechanisms underlying metabolic diseases. In this narrative review, we delve into the current literature on EDC toxicity effects on the liver and pancreatic tissues in terms of impaired mitochondrial function and redox homeostasis.

Effects of Cannabidiol, ∆9-Tetrahydrocannabinol, and WIN 55-212-22 on the Viability of Canine and Human Non-Hodgkin Lymphoma Cell Lines

In our previous study, we demonstrated the impact of overexpression of CB1 and CB2 cannabinoid receptors and the inhibitory effect of endocannabinoids (2-arachidonoylglycerol (2-AG) and Anandamide (AEA)) on canine (Canis lupus familiaris) and human (Homo sapiens) non-Hodgkin lymphoma (NHL) cell lines' viability compared to cells treated with a vehicle. The purpose of this study was to demonstrate the anti-cancer effects of the phytocannabinoids, cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC), and the synthetic cannabinoid WIN 55-212-22 (WIN) in canine and human lymphoma cell lines and to compare their inhibitory effect to that of endocannabinoids. We used malignant canine B-cell lymphoma (BCL) (1771 and CLB-L1) and T-cell lymphoma (TCL) (CL-1) cell lines, and human BCL cell line (RAMOS). Our cell viability assay results demonstrated, compared to the controls, a biphasic effect (concentration range from 0.5 μM to 50 μM) with a significant reduction in cancer viability for both phytocannabinoids and the synthetic cannabinoid. However, the decrease in cell viability in the TCL CL-1 line was limited to CBD. The results of the biochemical analysis using the 1771 BCL cell line revealed a significant increase in markers of oxidative stress, inflammation, and apoptosis, and a decrease in markers of mitochondrial function in cells treated with the exogenous cannabinoids compared to the control. Based on the IC50 values, CBD was the most potent phytocannabinoid in reducing lymphoma cell viability in 1771, Ramos, and CL-1. Previously, we demonstrated the endocannabinoid AEA to be more potent than 2-AG. Our study suggests that future studies should use CBD and AEA for further cannabinoid testing as they might reduce tumor burden in malignant NHL of canines and humans.

Rats' testicular toxicity induced by bisphenol A is lessened by crocin via an antiapoptotic mechanism and bumped P-glycoprotein expression

Bisphenol A (BPA) engenders testicular toxicity via hydroxyl free radical genesis in rat striatum and depletion of the endogenous antioxidants in the epididymal sperms. The multi-drug resistance efflux carrier; P-glycoprotein (P-gp) expel the BPA from the testis and is responsible for the testicular protection through the deactivation of numerous xenobiotics. In our study, we investigated whether the BPA-induced testicular toxicity could be circumvented through administration of an antioxidant; crocin (Cr). Implication of P-gp expression was also investigated. Rats administered BPA (10 mg/kg b.w. orally for 14 days), dropped the body weight, testes/body weight ratio, total protein content, testosterone, follicle stimulating hormone, luteinizing hormone, and sperm motility & count, total antioxidant status, glutathione content and antioxidant enzymes (superoxide dismutase and catalase), concomitant with the elevation of the percentage abnormal sperm morphology, as well as testicular lipid peroxides and nitrite/nitrate levels. Histopathological examination showed spermatogenesis disorders after the BPA rats exposure. The immunohistochemical study showed up-regulation of the P-gp as evident by increasing immunoreactivity in interstitial cells, with positive localization in some spermatogonia cells. The BPA-treated rats showed positive immunoreactivity against caspase-3. The co-intake of Cr (200 mg/kg b.w./day, i.p. 14 days) along with the BPA, significantly ameliorated all the mentioned parameters, boosted histopathological image, fell the caspase-3 up-regulation, and perched the P-gp expression. We showed that, Cr promotes P-gp as an approach to nurture the testicles against the BPA toxicity. In conclusion; Cr lessens the oxidative stress conditions to safeguard rats from the BPA-induced testicular toxicity and sex hormones abnormalities, reducing apoptosis and up-regulating P-gp.

Evaluate the in vitro effect of anthracycline and alkylating cytophosphane chemotherapeutics on dopaminergic neurons

BACKGROUND

Iatrogenesis is an inevitable global threat to healthcare that drastically increases morbidity and mortality. Cancer is a fatal pathological condition that affects people of different ages, sexes, and races around the world. In addition to the detrimental cancer pathology, one of the most common contraindications and challenges observed in cancer patients is severe adverse drug effects and hypersensitivity reactions induced by chemotherapy. Chemotherapy-induced cognitive neurotoxicity is clinically referred to as Chemotherapy-induced cognitive impairment (CICI), chemobrain, or chemofog. In addition to CICI, chemotherapy also causes neuropsychiatric issues, mental disorders, hyperarousal states, and movement disorders. A synergistic chemotherapy regimen of Doxorubicin (Anthracycline-DOX) and Cyclophosphamide (Alkylating Cytophosphane-CPS) is indicated for the management of various cancers (breast cancer, lymphoma, and leukemia). Nevertheless, there are limited research studies on Doxorubicin and Cyclophosphamide's pharmacodynamic and toxicological effects on dopaminergic neuronal function.

AIM

This study evaluated the dopaminergic neurotoxic effects of Doxorubicin and Cyclophosphamide.

METHODS AND RESULTS

Doxorubicin and Cyclophosphamide were incubated with dopaminergic (N27) neurons. Neuronal viability was assessed using an MTT assay. The effect of Doxorubicin and Cyclophosphamide on various prooxidants, antioxidants, mitochondrial Complex-I & IV activities, and BAX expression were evaluated by Spectroscopic, Fluorometric, and RT-PCR methods, respectively. Prism-V software (La Jolla, CA, USA) was used for statistical analysis. Chemotherapeutics dose-dependently inhibited the proliferation of the dopaminergic neurons. The dopaminergic neurotoxic mechanism of Doxorubicin and Cyclophosphamide was attributed to a significant increase in prooxidants, a decrease in antioxidants, and augmented apoptosis without affecting mitochondrial function.

CONCLUSION

This is one of the first reports that reveal Doxorubicin and Cyclophosphamide induce significant dopaminergic neurotoxicity. Thus, Chemotherapy-induced adverse drug reaction issues substantially persist during and after treatment and sometimes never be completely resolved clinically. Consequently, failure to adopt adequate patient care measures for cancer patients treated with certain chemotherapeutics might substantially raise the incidence of numerous movement disorders.