Poison arrows of ancient warriors can be a new male contraceptive

There is no shortage of scientific studies trying to find an effective and safe male version of pills against unwanted pregnancy. However, it is unlikely that some other candidate for this role has the same deadly prehistory.

Scientists have proposed the use of a very unusual chemical substance that may be suitable for creating a male contraceptive. It was found in a plant extract that African warriors and hunters commonly used as a poison to stop the heart. They rubbed arrowheads.

A research team from the universities of Minnesota and Kansas discovered that Ouabain, a toxic substance derived from two types of African plants, could serve as the basis for a "male contraceptive."

In its original form, Ouabain is found in the roots, stems, leaves and seeds of plants of the species Acokanthera schimperi and Strophanthus gratus. They grow in eastern Africa. Their Ethiopian warriors used more than two thousand years ago.

Like their Kenyan, Tanzanian, Rwandan and Somali “colleagues,” Ethiopian hunters and warriors extracted toxic substance by boiling the plant on fire, and then dipped arrowheads into the resulting liquid.

Fast forward to a couple of hundred years ago: 18th century European scientists found that the extract acts as a cardiac glycoside. This is a group of herbal medicines that have cardiotonic and antiarrhythmic effects in therapeutic doses, but in large doses, these substances are heart poisons.

Because of these properties, Ouabain in very small doses was previously used to treat diseases such as hypotension and arrhythmia. Although it is still considered a hazardous substance today, for example, in the USA Ouabain cannot be used in medical practice.

Nevertheless, this dangerous poison can wait for reincarnation: at least in a new and safe role. Scientists say that the extract can potentially affect male fertility (the ability to produce offspring).

Previous studies have shown that Ouabain can "subordinate to his will" the fertility of men, but because of the ability to interfere with the work of the human heart, it was recognized as dangerous for use as a contraceptive.

©Depositphotos / Ouabain chemical compound

Now, scientists conducted a series of experiments with male rats to show: after changing the structure of molecules, the modified analogue of Ouabain is still able to curb animal fertility. In this case, the substance is more non-toxic: it does not affect the heart and other systems.

When removing a group of sugars from the molecule of this compound and replacing its lactone group with a triazole group, the resulting Ouabain derivative targets spermatozoa in the rat and then reduces their mobility. In fact, this leads to male infertility.

A promising result (scientists investigated the molecular subtleties of the process) could lead to the creation of new male contraceptives. It is important that the effect of the substance is reversible, the authors note.

However, while the use (and even testing) of a modified substance in humans is not even planned. However, if this happens, the new pill will take its beginning in the poisonous arrowheads from the past.

The illustrations are used in agreement with the Depositphotos photobank