What are the challenges associated with evaluating and predicting the validity of animal models of type 1 and type 2 diabetes as tools for preclinical assessment and the discovery of new drugs and therapeutic agents for use in humans?

 

Re-written summaries by: Anuva Gajjar

Date Published: 2/20/2022

Original research links:

https://pubmed.ncbi.nlm.nih.gov/27595114/

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Introduction:

Diabetes mellitus is a chronic metabolic disorder that affects how the body processes sugar. When someone has diabetes, their body either doesn't make enough insulin (a hormone that helps control blood sugar levels) or doesn't use insulin properly. Insulin helps to regulate blood sugar levels by allowing sugar to be taken up by cells and used for energy. If there isn't enough insulin or the body can't use it properly, sugar builds up in the blood instead of being used by the body's cells. This can lead to a number of health problems, including heart disease, nerve damage, and kidney damage.

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To study diabetes and try to find ways to treat it, researchers use animals that have been made to have diabetes. These animals are called "animal models." Animal models can be used to study the causes of diabetes, the ways in which it develops and progresses, and the potential ways to prevent or treat it. There are several different types of animal models of diabetes, each with its own strengths and limitations. Choosing the right animal model depends on the specific research question being addressed.

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Methods:

The researchers in this study conducted a review of the literature on animal models of diabetes mellitus. They looked at a variety of sources, including scientific journals, textbooks, and online databases, and focused on studies published in English between 2005 and 2015. They analyzed the available research to summarize the current knowledge on the different types of animal models that are used to study diabetes, and how well these models reflect the human disease.

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Results:

The researchers found that there are several different animal models of diabetes mellitus. Some of these models are "spontaneous" models, meaning that they naturally develop diabetes. For example, non-obese diabetic mice are a type of spontaneous animal model that develops diabetes due to a mutation in their genes. Other animal models are "chemically induced" models, meaning that they are given a chemical that causes them to develop diabetes. For example, streptozotocin is a chemical that can be given to rats to cause diabetes. Finally, there are "genetically engineered" models, in which the animal's genes are modified to cause diabetes. For example, leptin-deficient mice are a type of genetically engineered animal model that develops diabetes due to a mutation in the leptin gene, which plays a role in the regulation of blood sugar levels.

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Each type of animal model has its own strengths and limitations. Spontaneous models may more closely mimic the natural course of human diabetes, but they may also be more difficult to study due to the variability in the timing and severity of the disease. Chemically induced models are easier to study because the timing and severity of the disease can be more easily controlled, but they may not accurately reflect the natural course of human diabetes. Genetically engineered models offer the advantage of being able to study specific genes or pathways involved in the development of diabetes, but they may not fully replicate the complex genetic and environmental factors that contribute to the disease in humans.

 

Conclusion:

Animal models are important tools for studying diabetes mellitus and trying to find new treatments. They allow researchers to investigate the underlying causes of the disease, the ways in which it develops and progresses, and the potential ways to prevent or treat it. However, it is important to carefully consider the strengths and limitations of each type of animal model when choosing the appropriate model for a specific research question. Further research is needed to fully understand the mechanisms underlying the development and progression of diabetes and to identify potential therapeutic targets.