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A new route for the synthesis of fatty alcohol derivatives of hydroxytyrosol and other olive oil phenolic compounds was developed to allow the preparation of unsaturated derivatives. The biological activity of synthesized compounds was evaluated. Most of the compounds presented a significant antioxidant activity on low-density lipoprotein (LDL) particles. The activity of the tested products was significantly influenced by the number and position of unsaturations as well as modifications on the polar head of the synthesized compounds. Some of them presented modulation of food intake in rats and, due to their molecular similarity with CB(1) endogenous ligands, the endocannabinoid system and PPAR-α were also evaluated as potential targets. The pharmacodynamics could not be totally explained by CB(1) and PPAR-α receptor interactions because only two of the four compounds with biological activity showed a CB(1) activity and all of them presented low PPAR-α affinity, not justifying its whole in vivo activity. The hydroxytyrosol linoleylether (7) increased LDL resistance to oxidation with a capacity similar to that of hydroxytyrosol and was the most active in vivo compound with a hypophagic effect comparable to that of oleoylethanolamine. We consider that this compound could be a good lead compound for future drug development in obesity treatments.

Trans-urocanic acid is a major chromophore for ultraviolet (UV) radiation in human epidermis. The UV induces photoisomerization of trans-urocanic acid (tUCA) form to cis-urocanic acid (cUCA) and has been reported as an important mediator in the immunosuppression induced by UV. This immunomodulation has been recognized as an important factor related to skin cancer development. This is the first time that UCA isomers have been measured in epidermis of skin biopsies from patients with squamous cell carcinoma (SCC) and with basal cell carcinoma (BCC) and compared with the tumor periphery and biopsies of healthy photoexposed and non-photoexposed skin as controls. The UCA isomers were separated and quantified by high performance liquid chromatography. Analysis of UCA in healthy skin showed significant increase in total UCA content in non-photoexposed body sites compared with highly exposed skins. In contrast, the percentage of cUCA was higher in photoexposed body sites. Maximal levels of cUCA were found in cheek, forehead and forearm and lower levels in abdomen and thigh. No differences were found in total UCA concentration between the tumor samples and healthy photoexposed skin. However, differences were found in relation between isomers. Higher levels of cUCA were detected in SCC biopsies (44% of total UCA) compared with samples of BCC and that of healthy photoexposed skin (30%). These results suggest that the UV radiation exposure, a main factor in development of SCC can be mediated, apart from direct effect to cells (DNA damage), by immunosuppression pathways mediated by high production of cUCA.

A basic principle of molecular and clinical medicine states that the function of the organs and the cells they are made up of is determined by the overall set of specific proteins. Therefore, the function of each organ depends on the molecules present in each cell, and hence it comes as no surprise to find that when tissue function is altered, different changes have taken place in the proteins. In the nervous system there are numerous examples of changes in proteins that correlate with functional alterations, either during normal or pathological development.In order to understand these relations, and to establish models in which to study the aetiopathogenesis of the disease, it is necessary to direct steady synthesis or to suppress synthesis in the brain of the protein that is potentially involved in the development of the disease. In consequence, it is possible to determine whether the presence or the absence of the protein is the direct or indirect cause of the effects; this is one of the main goals that must be achieved in order to enable researchers to define potential therapeutic targets in hereditary diseases. In order to manipulate the specific protein causing a pathology, we use experimental animal models as essential research tools, since they enable us to determine which mechanisms are altered and how the function of a particular protein affects the mechanisms being studied.Suppressing a gene or its over-expression in models using genetically modified mice will provide us with a means of modifying the genome and, eventually, the protein in the different tissues as well as in the nervous system in an attempt to imitate the genetic pathology that involves mental retardation. By controlling or suppressing the expression of a protein in the brain it becomes possible to remodel the functional profile of the tissue and study the consequences of molecular genetic manipulation, together with the biochemical, cytological and physiological processes, under normal basal conditions and under specific stimuli or conditions such as stress.