Cow’s milk could one day be a solution for millions of people with diabetes. This is the hope of the authors of the study published this month in the Biotechnology Journalwhich used the same principle used in the production of injectable insulin to create a genetically modified cow, capable of producing milk with proteins necessary for the production of human insulin.
The discovery of insulin and its role in diabetes occurred in 1921. For many years diabetics were treated with insulin from the pancreas of cattle and pigs, but in 1978 the first human insulin was produced using proteins from the genetically modified E. Coli bacteria. modified which, together with similar processes that use yeast instead of bacteria, constitute the main source of medical insulin to date.
Thus, the use of cows to provide human insulin is not new, but the study now published comes for the first time to prove that the production of “human” insulin is possible through a genetically modified bovine.
Insulin production: “The cow basically carried out this process on its own”
The team led by researcher Matt Wheeler, from the University of Illinois Urbana-Champaign, inserted a specific segment of human DNA that encodes proinsulin (a protein that is converted into insulin) into the cell nuclei of 10 cow embryos, which were then inserted in the uterus of normal cows.
Of these 10 genetically modified embryos, only one of these developed into a pregnancy and generated a transgenic calf. When it reached maturity, the team made several attempts to fertilize the genetically modified cow, but were unsuccessful.
Finally, they managed to get the cow to produce milk through hormonal induction, using a method attributed to animal reproduction specialist Pietro Baruselli, from the University of São Paulo. The little milk she produced over a month was examined for specific proteins.
The researchers discovered molecular masses similar to proinsulin and human insulin, which were not present in the milk of non-GMO cows. The research results suggest that enzymes in cow’s milk may have converted “human” proinsulin into insulin.
“Our goal was to produce proinsulin, purify it into insulin and go from there, but the cow basically did that process on its own. The cow produces about three to one biologically active insulin to proinsulin,” explained Wheeler, in a statement.
“Mother Nature designed the mammary gland as a factory to produce protein in a really efficient way. We can take advantage of this system and produce a protein capable of helping hundreds of millions of people around the world”says the researcher from the University of Illinois.
Canva
Solution to guarantee the global supply of insulin?
A typical unit of insulin is 0.0347 milligrams, so if, as Wheeler suggests, each cow could produce one gram of insulin per liter of milk, the result would be more than 28,800 units of insulin.
“Specialized, high-health facilities would be needed for livestock production, but it is nothing out of the ordinary for the well-established dairy industry.”says Wheeler.
Given these results, the North American researcher foresees “a future where a herd of 100 heads could produce all the insulin needed for the country” and goes even further, admitting that “a larger herd could produce the entire world’s supply in a year.”
