Diabetes has become a pandemic, with hundreds of new cases being diagnosed daily. Diabetes is caused by the lack of insulin produced by beta cells (type 2 diabetes) or total absence of insulin (type 1 diabetes). Uncontrolled diabetes can lead to various complications and untimely death of patients.
A recent study has linked vitamin A with diabetes, which suggests that vitamin A can enhance the functioning of beta cells.
Vitamin A and diabetes
There are about 220 different receptors present on the surface of beta cells, but the purpose of these receptors has long been unknown. Amongst these receptors, large reserves of vitamin A cell surface receptors have been identified . Every cell surface receptor has specific functions. This study aimed to discover the function of the vitamin receptors present on beta cells.
To determine the role of vitamin A in diabetes, insulin cells from various sources like mice, non-diabetic and type 2 diabetic human donors were examined . During the study, researchers partially blocked the vitamin A receptor and then exposed the cells to sugar. When challenged with sugar, it was observed that the cell’s ability to secrete insulin reduced to about 30%. 
Similar inferences were made when insulin cells from type 2 diabetic donors were studied. Furthermore, it was seen that cells from type 2 diabetes patients secreted less amount of insulin in comparison to cells from healthy individuals.
This study also showed that in the absence of vitamin A the resistance power of beta cells to inflammation also reduces, and in the complete absence of this vitamin, the cells perish.  This finding is important in the case of type 1 diabetes, wherein beta cells are destroyed during the early stages of life. Thus, it can be inferred that vitamin A is vital for the development of beta-cells during the early stages of life and is needed for the proper functioning in later life, especially during inflammatory conditions. 
Experiments on animals like mice have shown that vitamin A is needed for the healthy development of beta cells. Thus, the same may be the case in humans, i.e., children must obtain the satisfactory quantity of vitamin A from their diet for the normal development of the beta cells.
Source of Vitamin A
Meat and dairy products are the main sources of vitamin A, hence for vegans and vegetarians, the options of rich natural sources of vitamin A are limited. Various dairy products enriched with vitamin A are available in the market along with other dietary supplements.
However, it is important to remember that increased intake of vitamin A from artificial sources can be harmful and lead to osteoporosis. Thus, excessive intake of vitamin A by the diabetic patient would not be advisable as it can have other harmful side effects. Thus, if researchers succeed in finding a new substance like small molecules or peptides which are analogous to vitamin A and have the capability of stimulating these receptors found on the cell surface than diabetes can be managed without the harmful effects of vitamin A overdose. 
Credit: Dr. Neha on behalf of Borderless Access
Copyright © 2017 BorderlessAccess
- Stefan Amisten, Israa Mohammad Al-Amily, Arvind Soni, Ross Hawkes, Patricio Atanes, Shanta Jean Persaud, Patrik Rorsman, Albert Salehi. Anti-diabetic action of all-trans retinoic acid and the orphan G protein coupled receptor GPRC5C in pancreatic β-cells. Endocrine Journal, 2017