3 Minute 3Rs podcast: April 2022 transcript

[NC3Rs]

It’s the third Thursday of April, and you’re listening to 3 Minute 3Rs, your monthly recap of efforts to replace, reduce and refine the use of animals in research. This month, we’re starting with a paper exploring how you and your facility’s environment could be affecting the reproducibility of studies.

[NA3RsC]

Measuring mouse behavior is of key interest to researchers, especially in the fields of neuroscience and genetics. However, even when test protocols are rigorously standardized, outcomes of these tests can differ widely between laboratories. There is a pressing need to understand this variability, especially the influence of the experimenter and the environment.

Martina Nigri and colleagues evaluated 4 commonly used behavioral tests in 2 mouse strains performed by 2 experimenters in 2 diverse laboratory environments. Their findings confirmed that the direction of strain effects was highly reproducible within and between tests. However, the experimenter and environment do impact the strain effect size without altering the direction of conclusions. Importantly the study emphasizes that agreement is reached by converging evidence from multiple measures that address the same trait. To learn more, click on the link in the description.

[NC3Rs]

Next, let’s look at an ex vivo system developed to study human energy regulation at the molecular level, which may have implications for the treatment of obesity.

There are two main types of adipose or fat tissue in the human body: brown and white. Typically, the more brown adipose tissue a person has, the less likely they are to be obese. Brown adipose tissue is mainly made up of beige adipocytes, which can dissipate energy, whereas white adipocytes store energy long-term. We know that beige adipocytes can transition into white adipocytes, but this has previously not been studied in primary human cells and much of our understanding comes from rodent studies.

Attila Vámos and colleagues investigated this molecular process in human-derived cells, translating previously obtained rodent data to their ex vivo system. Using this more human-relevant approach to understand how adipocytes transition and differentiate could offer new opportunities to exploit these processes for health benefits, such as improving energy metabolism and combatting obesity, while reducing reliance on rodent models. To learn more, click the link in the description.

And finally, work towards reaching a consensus on environmental enrichment for rodents.

[LabAnimal]

Many studies have investigated using environmental enrichment as a way to improve laboratory rodent welfare however definitions and applications of enrichment tend to vary between these studies, making it difficult to draw definitive conclusions.

In a new article, Anna Ratuski and Daniel Weary conducted a meta-review of 29 publications to better understand the definitions and goals of enrichment in the literature. Definitions greatly varied between studies and were mainly focused on what enrichment should achieve, and not on what it should look like. The authors suggest that going forward, studies on enrichment should explicitly describe what elements of the environment are modified and how they are believed to affect rodent welfare.

Clarifying how environmental enrichment is conceptualized and applied may help researchers and animal care staff identify the protocols that can best benefit laboratory rodents. And, given that many review articles support providing rodents with social housing, nesting material, shelters or opportunities for foraging, the authors suggest these should now be considered as basic housing components, and not enriched conditions.

To learn more about this study, read the full paper in Animals.

[NC3Rs]

That’s it for this month’s episode. 3 Minute 3Rs is brought to you each month by Lab Animal, the North American 3Rs Collaborative, and the NC3Rs. If you’re enjoying the show, why not rate and review it wherever you’re listening? It helps more people find the show and discover new ways to put the 3Rs into practice. Thanks for tuning in, we’ll see you next month for more 3Rs research.