Liver Studies in Dogs

The liver is an important organ in the body that helps regulate metabolism, detoxification, and many other functions necessary for survival. Age and diet influence liver function and as the body ages, liver function declines. Older dogs share many of the liver diseases that older humans have. An aged liver weighs less, and has a decline in blood flow, regeneration rate, and detoxification. In the paper that I am reviewing, liver tissue samples were collected from six senior and 6 young adult female beagles. All of these dogs were fed either a meat protein-based diet or a plant protein-based diet for a year. RNA was extracted from the liver tissue of each dog and was studied through canine microarrays to determine the expression of genes in the liver. Depending on the age of the dog, the diet altered nutrient digestibility, blood chemistry, gastrointestinal morphology, and microbial fermentation. The liver contains 13,778 genes and it was discovered that 234 of those genes were altered by age, and 137 genes were altered by diet. Alterations in the genes for an aged liver included cellular development, nutrient metabolism, and signal transduction. The gene expressions that were observed indicated that older dogs had an increased chance of liver disease and liver dysfunction, which have also been seen in older humans and mice. In the aged liver, inflammation, oxidative stress, and glycolysis genes were up-regulated while regeneration and cholesterol related genes were down-regulated. Diet affected gene expression more in the young adult dogs than in the older dogs. Young adults had thirty-three genes affected while older dogs had only three genes affected. Age and diet interactions appeared to be present because changes in the age related gene expression in the liver were more common in dogs fed the meat protein-based food (thirty-eight genes) than for dogs fed the plant protein-based food (twenty-one genes). These results provide insight into the molecular aspects of the liver and also predisposition to disease and irregularities in the liver. These results may help in a future study to determine if diet is a way to decrease age related liver dysfunction and disease.
I found this to be an interesting article because the liver is an organ that is necessary for all living beings to survive. The liver needs to be taken care of as much as possible and this article was researching how age and diet could affect the functionality of the liver. If we know what can damage the liver, then we can avoid foods and other things that could make the liver irreparable. Although age is not something that we can stop, we could help take care of our liver by watching what we ingest and what we do to our bodies that may affect liver function.

Erika