Responsible Science and Research Animal Use

Perspectives of FTIR as Promising Tool for Pathogen Diagnosis, Sanitary and Welfare Monitoring in Animal Experimentation Models: A Review Based on Pertinent Literature

Currently, there is a wide application in the literature of the use of the Fourier Transform Infrared Spectroscopy (FTIR) technique. This basic tool has also proven to be efficient for detecting molecules associated with hosts and pathogens in infections, as well as other molecules present in humans and animals' biological samples. However, there is a crisis in science data reproducibility. This crisis can also be observed in data from experimental animal models (EAMs). When it comes to rodents, a major challenge is to carry out sanitary monitoring, which is currently expensive and requires a large volume of biological samples, generating ethical, legal, and psychological conflicts for professionals and researchers. We carried out a survey of data from the relevant literature on the use of this technique in different diagnostic protocols and combined the data with the aim of presenting the technique as a promising tool for use in EAM. Since FTIR can detect molecules associated with different diseases and has advantages such as the low volume of samples required, low cost, sustainability, and provides diagnostic tests with high specificity and sensitivity, we believe that the technique is highly promising for the sanitary and stress and the detection of molecules of interest of infectious or non-infectious origin.

Glioblastoma Multiforme: Probing Solutions to Systemic Toxicity towards High-Dose Chemotherapy and Inflammatory Influence in Resistance against Temozolomide

Temozolomide (TMZ), the first-line chemotherapeutic drug against glioblastoma multiforme (GBM), often fails to provide the desired clinical outcomes due to inflammation-induced resistance amid inefficient drug delivery across the blood-brain barrier (BBB). The current study utilized solid lipid nanoparticles (SLNPs) for targeted delivery of TMZ against GBM. After successful formulation and characterization of SLNPs and conjugation with TMZ (SLNP-TMZ), their in-vitro anti-cancer efficacy and effect on the migratory potential of cancer cells were evaluated using temozolomide-sensitive (U87-S) as well as TMZ-resistant (U87-R) glioma cell lines. Elevated cytotoxicity and reduction in cell migration in both cell lines were observed with SLNP-TMZ as compared to the free drug (p < 0.05). Similar results were obtained in-vivo using an orthotopic xenograft mouse model (XM-S and XM-R), where a reduction in tumor size was observed with SLNP-TMZ treatment compared to TMZ. Concomitantly, higher concentrations of the drug were found in brain tissue resections of mice treated with SLNP-TMZ as compared to other vital organs than mice treated with free TMZ. Expression of inflammatory markers (Interleukin-1β, Interleukin-6 and Tumor Necrosis factor-α) in a resistant cell line (U87-R) and its respective mouse model (XM-R) were also found to be significantly elevated as compared to the sensitive U87-S cell line and its respective mouse model (XM-S). Thus, the in-vitro and in-vivo results of the study strongly support the potential application of SLNP-TMZ for TMZ-sensitive and resistant GBM therapy, indicatively through inflammatory mechanisms, and thus merit further detailed insights.

Use of animals in dental research: Trends and ethical reflections

This study aimed to survey and analyze the profile of experimental dental research in animals, verifying its trends. We evaluated studies developed with the use of animals in vivo, published in 10 dental journals with high impact factors, from 2015 to 2020. From 1652 studies retrieved, 594 involved in vivo experimentation on animals and were analyzed further. Rats were the species most used and with the highest mean of animals per study. Ferrets, although presenting the lowest rate of publications, had the second highest mean of animals per study. Periodontics was the dental specialty with the highest number of publications, while oral rehabilitation had the lowest number. The data on the institution responsible for reviewing animal research protocols approval, sample size, anesthesia and analgesia were provided in 93.10%, 83%, 70.54% and 23.74% of studies, respectively. In 53% of studies, euthanasia was specified and anesthetic overdose was the method most used. Over the period analyzed, there was a reduction in animal studies in vivo, and periodontics was the specialty that most used this experimental model. Although most studies mentioned approval by an ethics committee, some publications neglected to mention sample size, anesthesia and euthanasia. The omission of essential information may raise scientific and ethical concerns.

Improving preclinical studies through replications

The purpose of preclinical research is to inform the development of novel diagnostics or therapeutics, and the results of experiments on animal models of disease often inform the decision to conduct studies in humans. However, a substantial number of clinical trials fail, even when preclinical studies have apparently demonstrated the efficacy of a given intervention. A number of large-scale replication studies are currently trying to identify the factors that influence the robustness of preclinical research. Here, we discuss replications in the context of preclinical research trajectories, and argue that increasing validity should be a priority when selecting experiments to replicate and when performing the replication. We conclude that systematically improving three domains of validity - internal, external and translational - will result in a more efficient allocation of resources, will be more ethical, and will ultimately increase the chances of successful translation.