A cactus-derived toxin-like cystine knot Peptide with selective antimicrobial activity.

Naturally occurring cystine knot peptides show a wide range of biological activity, and as they have inherent stability they represent potential scaffolds for peptide-based drug design and biomolecular engineering. Here we report the discovery, sequencing, chemical synthesis, three-dimensional solution structure determination and bioactivity of the first cystine knot peptide from Cactaceae (cactus) family: Ep-AMP1 from Echinopsis pachanoi. The structure of Ep-AMP1 (35 amino acids) conforms to that of the inhibitor cystine knot (or knottin) family but represents a novel diverse sequence; its activity was more than 500 times higher against bacterial than against eukaryotic cells. Rapid bactericidal action and liposome leakage implicate membrane permeabilisation as the mechanism of action. Sequence homology places Ec-AMP1 in the plant C6-type of antimicrobial peptides, but the three dimensional structure is highly similar to that of a spider neurotoxin.

Ethnopharmacology - A journal, a definition and a society.

ETHNOPHARMACOLOGICAL RELEVANCE: Historical development of the Journal of Ethnopharmacology, the International Society of Ethnopharmacology, and the first definition of ethnopharmacology. AIM OF THE STUDY: To present the background to, and the people involved, in the foundation of the journal and the society. MATERIALS AND METHODS: Personal recollections, archival documents and photographs. RESULTS: A concise review of the early years of the JEP and the ISE, and the development of the first definition of ethnopharmacology. CONCLUSIONS: The definition of ethnopharmacology as an interdisciplinary science, and its establishment as a journal and a society was timely, filled a need, and opened up publication and meeting possibilities for scientists from various academic fields. Most important has been, and continues to be, the bridges created between people from all cultures and all countries.

Ecstasy analogues found in cacti.

Human interest in psychoactive phenethylamines is known from the use of mescaline-containing cacti and designer drugs such as Ecstasy. From the alkaloid composition of cacti we hypothesized that substances resembling Ecstasy might occur naturally. In this article we show that lophophine, homopiperonylamine and lobivine are new minor constituents of two cactus species, Lophophora williamsii (peyote) and Trichocereus pachanoi (San Pedro). This is the first report of putatively psychoactive phenethylamines besides mescaline in these cacti. A search for further biosynthetic analogues may provide new insights into the structure-activity relationships of mescaline. An intriguing question is whether the new natural compounds can be called "designer drugs."

Food for thought.

Do certain kinds of food contain pharmacologically active substances in concentrations that are high enough to have druglike effects when consumed? Are biologically active compounds in food indicative of therapeutic value? Is traditional drug development suitable for testing the merits of food? Is it ethical to test food as a drug on patients? Will dietary disease management remain a pipedream? Is it a fact or fantasy that the Mediterranean diet is beneficial to health? Is a vegetarian diet an elimination therapy, or one of supplementation? What can be learned from animals? Are humans losing the capability of listening to their bodies? In this review, we will address these questions--providing food for thought.

Prehistoric peyote use: alkaloid analysis and radiocarbon dating of archaeological specimens of Lophophora from Texas.

Two archaeological specimens of peyote buttons, i.e. dried tops of the cactus Lophophora williamsii (Lem.) Coulter, from the collection of the Witte Museum in San Antonio, was subjected to radiocarbon dating and alkaloid analysis. The samples were presumably found in Shumla Cave No. 5 on the Rio Grande, Texas. Radiocarbon dating shows that the calibrated 14C age of the weighted mean of the two individual dated samples corresponds to the calendric time interval 3780-3660 BC (one sigma significance). Alkaloid extraction yielded approximately 2% of alkaloids. Analysis with thin-layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS) led to the identification of mescaline in both samples. No other peyote alkaloids could be identified. The two peyote samples appear to be the oldest plant drug ever to yield a major bioactive compound upon chemical analysis. The identification of mescaline strengthens the evidence that native North Americans recognized the psychotropic properties of peyote as long as 5700 years ago.