Question 1

What is the Meaning of 17β-HSD?

Accepted Answer

17-beta-hydroxysteroid dehydrogenase (17β-HSD) is a family of enzymes crucial for the interconversion of various steroid hormones. These enzymes catalyze the oxidation or reduction at the C17 position of the steroid nucleus, fundamentally regulating the biological activity of sex steroids. They are essential gatekeepers in the final steps of steroidogenesis, determining the potency of circulating hormones. The different isozymes within this family exhibit distinct substrate specificities and tissue distributions. Understanding their function is vital for managing conditions related to estrogen and androgen excess or deficiency.

Question 2

What is the Origin of 17β-HSD?

Accepted Answer

The name is derived from the enzyme's function: "hydroxysteroid dehydrogenase" describes its role in adding or removing hydrogen (dehydrogenation) on a steroid molecule that possesses a hydroxyl group, specifically at the "17-beta" position on the steroid ring structure. This enzymatic activity was identified and characterized as part of the broader study of steroid hormone metabolism in the mid-20th century. The systematic nomenclature reflects its chemical action and location on the hormone backbone. Its discovery stemmed from the need to understand how precursor steroids like androstenedione are converted into potent androgens like testosterone.

Question 3

What is the Mechanism of 17β-HSD?

Accepted Answer

The enzyme operates by transferring a hydride ion between the C17 position of a steroid and a nicotinamide adenine dinucleotide (NAD+/NADH or NADP+/NADPH) cofactor. For example, the 17β-HSD type 1 enzyme converts the less potent estrone into the highly potent estradiol (E2). Conversely, the type 2 enzyme often catalyzes the reverse reaction, inactivating potent hormones into weaker forms. This bidirectional control allows tissues to precisely modulate the local concentration of active sex hormones, providing a mechanism for paracrine regulation. The balance of these interconversions significantly influences hormone-sensitive tissues such as the endometrium and prostate.

17β-HSD

Meaning

Origin

Mechanism

Can Resistance Training Improve DHEA Production in Aging Individuals?

Provided by the clinical team
at 4Ever Young Miami Dadeland

-15% ∞ HRTIO15

Your protocol begins with a conversation.

Visit

Schedule Appointment

About

Med & Wellness

4Ever Young Miami Dadeland

Communication

+1 786-529-6686

Email Us

Opening Hours