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Greece’s natural treasure in its bounty of medicinal plants

Greece’s biodiversity is one of the most highly developed in the world, providing valuable raw materials for many new medications. The pharmacology research laboratory at Athens University’s School of Pharmacy has been undertaking an important project involving the analysis of a number of Greek flora and pinpointing useful molecules that could comprise the basis for new mediations. «For a variety of reasons (defense, propagation), plants produce a number of substances that we call secondary metabolites, of which there are millions in nature, made in a way that no chemist could ever be able to imagine in the laboratory,» said Professor Leandros Skaltsounis, director of the laboratory. Skaltsounis’s research group is attempting to open up new pharmaceutical pathways by studying Greek flora. He has already amassed a collection of 500 plants, mostly from Crete, the Peloponnese, Epirus and central Greece. About 30-40 of these have been studied in depth, providing important information. For example, molecules with anti-epilepsy action have been isolated from the roots of the genus Paeonia. One of the reasons this particular plant was chosen was a reference in Dioscurides’ «On Materia Medica,» written in the first century AD. According to Dioscurides, the seed of the peony crushed in red wine stops menstruation and provides relief from crises of hysteria and pains in the uterus. The current study confirms these observations; it is not the only instance in which the laboratory has confirmed traditional evaluations of the properties of plants. «Nature does not make cures for cancer, but [it does make] molecules useful in defending plants from external factors. We isolate them, determine their structure and then see how we can improve them to make useful medications,» said Skaltsounis. Molecules of pharmacological interest are discovered by means of the following process. During the first stage, the biological action of plant extracts for various purposes (cancer, diabetes, diseases of the central nervous system, infections, osteoporosis or other diseases) is investigated. Then the extracts that have shown positive effect in a pharmacological test are studied in depth for the purpose of isolating the active molecules. The biological experiments are repeated on the pure molecules both in vitro and in vivo. At the same time, the active molecules are studied to find the active mechanism at cellular level. Laboratory results have been particularly encouraging. Of the plants endemic to Crete, Hypericum jovis and Verbascum spinosum, substances with a powerful anti-oxidant action, have been isolated at cellular level. Another very interesting category is the Leguminosae family (Onobruchis Ebenus, Trifolium) from which molecules have been isolated that imitate the action of estrogens, also known as phyto-estrogens, and which could be an interesting alternative to hormonal replacement therapy. Molecules with considerable biological action have also been isolated from cultivated plants and trees that produce many foods in the traditional Greek diet, such as olives and olive oil, many of which have molecules that can help protect cellular DNA. A process used for the first time in the laboratory has isolated substances with a powerful anti-microbe and healing action from Chios mastic gum. Mountain tea, of the genus Sideritis, contains molecules with a powerful anti-oxidant and anti-inflammatory action. We consume these substances by drinking the tea, but as Skaltsounis said: «Any molecule with an anti-oxidant action has positive results in many areas, from cardiovascular disease to cancer and stress.» The laboratory has shown a particular interest in the plants of Crete. «There is a high life expectancy in Crete, the result of the famous Cretan diet,» said Skaltsounis. «The biodiversity of Crete is truly impressive. There are about 1,820 species of higher plants, about 33 percent of Greece’s flora. At the same time, the fact that so many plants are found in the daily diet of Cretans is a unique phenomenon. We studied a number of plants such as Cichorium spinosum (stamnagathi, in Greek), Lathyrus ochrus (papoules) and Scrozonera cretica (skoulo). The biological action of the substances isolated clearly confirms the beneficial effects on the human organism.» Skaltsounis underlines the importance of a proper diet. «If one’s diet is good, many medications do not provide many benefits. Of course, one should not underestimate the need to create effective medications, nor should it give free rein to charlatans selling plant preparations for every kind of disease,» he warned. One of the laboratory’s most recent achievements has been the discovery of a substance derived from shells, the marine gastropods of the Muricidae family, which permits the propagation of stem cells, the archetypal human cells that are considered medicine’s great hope for the future, since they could be converted into any type of tissue desired, helping to repair it. This discovery has already been patented in cooperation with the Rockefeller Institute.