22 Mayo 2017 11:25
Prevent the sperm from reaching the egg. That's been the goal of contraceptive medicine for centuries. And since the time of the ancient Egyptians, the king of contraception has been the simple elongated sheath we all know as the condom.
Scientists at the University of Berkeley have discovered a universal method of contraception, which is 10 times more effective than other methods of contraception, works for both genders, presents no hormonal side effects and is acceptable even to anti-abortion activists. Sounds almost too good to be true, doesn't it?
In an article recently published in PNAS, the team of American researchers has presented its latest discovery: the molecular condom.
Traditionally, the aim of contraception has been to prevent sperm from reaching the egg. But what if the most effective solution lies in stopping the sperm actually entering the egg?
That is how the so-called molecular condom works.
When a spermatozoid tries to reach the egg, it must travel 24,000 times the length of its body. At the end of this epic journey, it still has one more challenge to overcome: it must penetrate the membrane of the female cell.
To achieve the force needed to enter the ovum, an ion channel called CatSper inside the sperm's tail activates to let calcium in which, in turn, produces the rapid propellor-like action of the tail, corkscrewing the head forward through the dense outer layers of the ovum.
This phenomenon – known to scientists as the 'power kick' – occurs thanks to the progesterone released by the corpus luteum that works as an activator in the process.
And that is where this new method of contraception enters the picture.
Researchers discovered a series of chemical compounds that have the capacity to sabotage this chemical reaction in the tail of sperm cells. Lupeol – which can be found in aloe, grapes, olives and cabbage – and pristimerin, which comes from a vine plant with the rather complicated scientific name Tripterygium wilfordii – otherwise known as the thunder god vine.
Lupeol and pristimerin inhibit the sperm cell's response to the progesterona, therefore preventing it from carrying out the 'power pick'.
Scientists at the University of Berkeley have discovered a universal method of contraception, which is 10 times more effective than other birth-control methods, works for both genders, presents no hormonal side effects and is acceptable even to anti-abortion activists.
One of the positive aspects of this method of contraception is the fact that anti-abortion advocates, who believe life starts at conception, can't object, as there is no embryo at any point. 'This method is not only 10 times more effective than anything currently on the market, but it clearly prevents fertilization,' explained study leader and biophysicist Polina Lishko.
Trials on primates are already underway and the first results are expected later this year. If all goes well, human trials could be given the go ahead within a few years.