Does Vitamin A play A Role In Testosterone Regulation?

Vitamin A occurs naturally in a variety of foods in a special precursor form that is known as beta-carotenoid. The carotenoids obtained from the dietary sources are converted into Vitamin A with the help of special enzyme that is known as Bco1.

Research conducted by researchers at the University of Illinois suggested that the Bco1 enzyme also plays a major role in the regulation of serum testosterone levels. In addition, Bco1 also regulates prostatic growth. Researchers at the University of Illinois discovered these findings while studying the effects of missing Bco1 gene on the laboratory mice.

Bco1 enzyme and it’s functions within the human body:

Bco1 enzyme exert its actions in the human body by converting one Beta – Carotene molecule obtained from dietary sources into two vitamin A molecules that serves a variety of functions in the human body.

Research conducted in laboratory mice models suggested that hereditary deficiency or dysfunction of this enzyme can affect the metabolism of beta carotenes in the body and along with various biological functions, can also affect the regulation of testosterone levels.

The lead author of the paper, Joshua W. Smith suggested that even genetic variations in the genes of Bco1 gene that may affect the biological activity of enzyme can impact the testosterone metabolism and regulation in the human body.

Relationship between the Testosterone Regulation in the human body and Bco1 gene:

Research team at the University of Illinois conducted a study on laboratory mice – test group had no Bco1 activity due to lack of enzyme, whereas the control group had normal activity of Bco1 enzyme. Both groups of mice were fed Beta-carotene rich diet along with ample quantities of Vitamin A to maintain normal biological functions.

The research team discovered that:

• Mice with no biological activity of Bco1 gene had lower serum levels of testosterone, whereas the serum levels were unaffected in the control group.
• The prostate gland and seminal vesicles were also found to be shrunken among test subjects because testosterone plays a key role in the growth of prostate gland as well as other key male reproductive organs
• The Leydig cell concentration in testosterone was found to be 44% lower than the control sample among mice with no Bco1 activity
• A significant reduction in the serum levels of Hsd17b3 was also reported in mice with no Bco1 enzyme – which plays a key role in the synthesis of testosterone

It is imperative to mention that lack of Hsd17b3 at young age/ birth can present with femininized external genitalia in male babies and low testosterone.

Scientists also discovered that 13 of 200 genes that plays a key role in the prostate metabolism are altered in study samples with no or low Bco1 activity as often observed in genetic variations/ alterations of Bco1. It is believed that lack of Bco1 activity can disrupt the activity at androgen receptors that is vital to prostate growth and testosterone regulation. Needless to say that similar mechanisms can also aggravate the risk of developing prostate cancer in such subjects.