A new bioluminescent imaging technology for studying oxidative stress in the testis and its impacts on fertility

A quantitative weight-of-evidence review of preclinical studies examining the potential developmental and reproductive toxicity of acetaminophen

We previously developed a quantitative weight-of-evidence (QWoE) framework using prespecified scoring criteria for preclinical acetaminophen data to characterize potential developmental neurotoxicity outcomes with considerations for biological relevance of the response to adverse outcomes and the strength of methods and study design. The current analysis uses this framework to characterize potential developmental and reproductive toxicity (DART) outcomes following exposure to acetaminophen. Two-hundred forty-two QWoE entries were documented from in vivo rodent studies identified in 110 publications across five categories: DART endpoints in the context of (1) periadolescent/adulthood (nonpregnancy) exposures; (2) pregnant female exposures; and, for in utero or other developmental exposures, (3) anatomical abnormalities, (4) reproductive development, and (5) other physical development. A mean outcome score and methods score were calculated for 242 QWoE entries. Data analyzed in our framework were of moderate quality showing no consistent evidence of DART in male and female rodents following exposure to acetaminophen at therapeutic and/or non-systemically toxic doses. Similar results were found for the individual context- and outcome-related endpoint analyses and as segregated by sex. Overall, this QWoE analysis on the in vivo rodent data demonstrated no consistent evidence of adverse effects following exposure to therapeutic and/or non-systemically toxic acetaminophen on development or on the structure and function of the reproductive system.

The oxygen puzzle in FLASH radiotherapy: A comprehensive review and experimental outlook

FLASH radiotherapy is attracting increasing interest because it maintains tumor control while inflicting less damage to normal tissues compared to conventional radiotherapy. This sparing effect, the so-called FLASH effect, is achieved when radiation is delivered at ultra-high dose rates (≥40 Gy/s). Although the FLASH effect has already been demonstrated in several preclinical models, a complete mechanistic description explaining why tumors and normal tissues respond differently is still missing. None of the current hypotheses fully explains the experimental evidence. A common point between many of these is the role of oxygen, which is described as a major factor, either through transient hypoxia in the form of dissolved molecules, or reactive oxygen species (ROS). Therefore, this review focuses on both forms of this molecule, retracing old and more recent theories, while proposing new mechanisms that could provide a complete description of the FLASH effect based on preclinical and experimental evidence. In addition, this manuscript describes a set of experiments designed to provide the FLASH community with new tools for exploring the post-irradiation fate of ROS and their potential biological implications.

Ameliorative Effect of Crocin on Sperm Parameters and In Vitro Fertilization in Mice under Oxidative Stress Induced by Paraquat

Background

Paraquat (PQ) is an herbicide that is genotoxic and cytotoxic for male germ cells. In this study, we investigated the protective role of crocin (Cr) against the destructive effects of PQ on sperm quality and in vitro fertilization (IVF) outcomes.

Materials and Methods

In this experimental study, a total of 28 male mice (20-25 g) were divided into four groups: control, which received intraperitoneal (IP) injections of 0.1 ml normal saline per day; PQ group received IP injections of PQ (5 mg/kg/day); experimental (PQ+Cr group) received PQ along with IP injections of Cr (200 mg/kg/day); and positive control (Cr) received IP injections of Cr (200 mg/kg/day). In the last two weeks of the treatment period (35 days of treatment), 16 non-pregnant mice were stimulated to receive adult oocytes. At the end of the treatment period, after euthanizing the mice, the sperms were extracted from the epididymis of each mouse and prepared for evaluation of sperm parameters and IVF.

Results

In the PQ+Cr group, Cr caused a significant increase in the average number of sperms and the mean percent- age of motile and viable sperms. There was a significant decrease in the mean number of immature and DNA-damaged sperms compared to the PQ group (P<0.001). IVF evaluation in the PQ+Cr group showed that the mean percentage of fertilization, two- and four-cell embryos, blastocysts, and hatched embryos significantly increased. Cr caused a significant decrease in the mean percentage of the arrested embryos compared to the PQ group (P<0.001). However, the Cr group did not have any toxic effects on sperm quality or IVF results.

Conclusion

The findings of this study showed that Cr, due to its effective and potent antioxidant properties, could reduce or suppress the destructive effects on sperm parameters and IVF caused by PQ.

Non-invasive Bioluminescence Monitoring of Hepatocellular Carcinoma Therapy in an HCR Mouse Model

Animal models play crucial roles in the development of anticancer therapeutics. The ability to quickly assess the localized primary hepatocellular carcinoma (HCC) status in a non-invasive manner would significantly improve the effectiveness of anti-HCC therapeutic studies. However, to date, animal models with this advantage are extremely scarce. In this study, we developed a novel animal model for the fast assessment of drug efficacy against primary HCC in vivo. HCC was induced in immunocompetent hepatocarcinogenesis reporter (HCR) mice by diethylnitrosamine (DEN) injection and confirmed by histopathological staining. Using the bioluminescence imaging (BLI) technique, HCC progression was longitudinally visualized and monitored in a non-invasive way. Tests of two clinical drugs showed that both sorafenib and oxaliplatin significantly inhibited the BLI signal in mouse liver in a dose-dependent manner. The in vivo intensity of BLI signals was highly consistent with the final tumor burden status in mouse liver after drug treatment. The inhibitory effect of anti-HCC drugs was accurately evaluated through in vivo BLI intensity detection. Our study successfully established a bioluminescence mouse model for non-invasive real-time monitoring of HCC therapy, and this HCR mouse model would be a useful tool for potential anti-HCC drug screening and new therapeutic strategy development.