Spinneret - Weaving the chemical web one molecule at a time...

The BBC reports today that malaria has started to evolve resistance to the artemesinin family of drugs that are used as the world’s front-line defense against the most prevalent and deadly form of the disease.

Artemesinin emerged from a Chinese herbal medicine, Qinghaosu, where it was used as a fever treatment for generations. I remember writing about the earliest research in my New Scientist days and have watched the drug discovery process bring us to the point where a potent pharmaceutical could, it seemed, defeat the disease…

…no more. In Cambodia, at least, resistant strains of malaria have been spotted by two teams of scientists, working on separate clinical trials who reported disturbing evidence of reduced drug efficacy.

The BBC says researchers are blaming a weak public health system and poorly controlled drug use, as well as fake drugs, produced by international criminals, for the problem. But, the problem is not really socioeconomic at all - it’s natural selection in action. We present the disease with a changing environment and it evolves to fill the niche.

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N-Acetyl-L-tyrosine is showing up in spam emails and on twitter so I had to take a look to find out what claims are being made for it. I suspected that marketers might be calling it a panacea, and I was right. At least one website (which mentions, hilariously, FDA censorship on this) lists several diseases, disorders and conditions, that the compound (a metabolic precursor of tyrosine) might help with. Although they don’t say specifically that it’s the N-acetyl-L-tyrosine functioning medically but allude to its putative activity on the basis that tyrosine itself supposedly has these activities.

They claim that the compound is a precursor for the neurotransmitters dopamine and norepinephrine, a precursor for the pigment compounds melanins, and for the thyroid hormones (e.g. thyroxin). Lifelink, for instance, makes the bold statement:

Most of the medical research relating to tyrosine supplementation has been conducted using L-tyrosine itself, not acetyl-L-tyrosine. It is logical to assume, however, that the conclusions reached will apply to acetyl-L-tyrosine as well, since the latter is converted to L-tyrosine in the body. The following discussion therefore draws from studies of L-tyrosine.

By implication then N-acetyl-L-tyrosine can purportedly be used in treating mood problems and depression, hair and skin colour, blood pressure, and Parkinson’s disease!

If you were offered a drug by your physician to improve your hair colour but the doc then pointed out that it might affect your brain and your blood pressure, wouldn’t you be worried? Indeed, the pharmaceutical industry spends billions of dollars trying to eliminate side effects and focus the specificity of its products to avoid such issues as multiple activities of any given drug.

Several of the references given to support the use of N-acetyl-L-tyrosine are nothing more than Wikipedia entries. I don’t want wiki entries when I’m assessing a medical effect, it’s not that Wiki is not credible, but how can the lay reader be sure that what they’re reading on there is valid, it may have been edited to promote the compound by someone with a vested interest or a conflict of interest.

Give me large-scale, randomized, double-blind, placebo-controlled, clinical trials every time and you’ll convince me. Spurious musings on possible benefits are not medical evidence.

Also of note are the physical properties of N-acetyl-L-tyrosine listed by ChemSpider:

CAUTION: May irritate eyes, skin, and respiratory tract

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According to an AP investigation, US pharma companies have released at least 1000 tonnes of pharmaceuticals into American waterways. This putative contamination of the drinking water supply has been consistently overlooked by the Federal government, their report says.

Interestingly, this drugs in the water supply is a topic I discussed at least a decade ago in the original ChemWeb Catalyst column (now available on Sciencebase.com) and one that was also in the news in India not too long ago: Indian Stream A Cocktail Of Drugs. The exact same news was also discussed back in January on the thdblog: Pharmaceutical Waste Dumped at Record Levels.

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