Researchers Found Perfect Contraceptives In Traditional Chinese Medicine (inverse.com)

hackingbear writes: Researchers at U.C. Berkeley found a birth control that was hormone-free, 100 percent natural, resulted in no side effects, didn't harm either eggs nor sperm, could be used in the long-term or short-term, and -- perhaps the best part of all -- could be used either before or after conception, from ancient Chinese folk medicine... "Because these two plant compounds block fertilization at very, very low concentrations -- about 10 times lower than levels of levonorgestrel in Plan B -- they could be a new generation of emergency contraceptive we nicknamed 'molecular condoms,'" team leader Polina Lishko.

Comments

Re:At least some B's in there

[ShanghaiBill]

The actual paper is paywalled, but the abstract says nothing about working "the morning after", so the journalist who wrote TFA may have just made that up.

Not a contraceptive and far from perfect

[pesho]

This is another PR statement that inflates the actual findings so much that they become unrecognizable. For those interested in the details, the original article is here (it is paywalled). The TL;DR version of the original article is as follows:

1. 1. There is a protein (ABHD2) that controls sperm motility.
2. 2. ABHD2 activated progesterone and is blocked by other steroid hormones.
3. 3. After ovulation progesterone is released by the cumulus cells that surround the egg. This release of progesterone activates nearby sperm to move faster.
4. 4. There is a class of compounds produced by plants that are called triterpenoids. Some of these compounds mimic steroid hormones.
5. 5. By virtue of their ability to mimic steroid hormones two triterpenoids (pristimerin and lupeol) can bind to ABHD2 and block it in the same way steroid hormones do.

These were the finding of the papers. Now look at the claims in the PR statement:

1. 1. Traditional Chinese medicine. There is hardly a plant or organic matter that is not used for one purpose or other in traditional Chinese medicine (Traditional Chinese medicine is akin to internet porn - if something exists there is a traditional Chinese medicine made from it). Plants make insane diversity of chemical compounds. Anyone will be hard pressed to find a naturally occurring plant compound that does not exist in at least one plant used by traditional Chinese medicine. While this claim may technically be true, it is completely meaningless.
2. 2. Contraceptive activity of the compounds. The compounds had marginal inhibitory effect (6-10%) on sperm motility when the sperm was activated with progesterone, and no effect on the motility of sperm not activated by progesterone. Will this prevent fertilization? The study did not report the results of experiments that will directly test the contraceptive effect of the compounds. This claims is obviously false.
3. 3. The compounds are not hormonal. Technically speaking, they are not steroid hormones. In reality, they act as steroid hormones, otherwise they would not have been able to block ABHD2. This claims seems patently false to me.
4. 4. "Perfect contraceptives". If you scan the research literature with the names of the compounds you will find that they exhibit all kinds of completely unrelated activities when applied to human cells. This means that one or more of the following are true; (i) these are "sticky" compounds that hit multiple targets; (ii) The compounds are not pure and is impossible to tell if what you observe is the activity of the compound or of the impurities (this happens very often when isolating compounds from plants); (iii) The compounds hit target that is important for many cell types in the body. Regardless of what the explanation is, these compounds are no "magic bullets". "Carpet bombing" seems to be more suitable analogy.