Hülya GÜLTEKİN, Serkan ŞAHİN, Nurten BUDAK

BESLENME DAVRANIŞI: FARMAKOLOJİK HEDEF MOLEKÜLLER

Şişmanlık veya zayıflık; enerji harcanması ve besin alımı arasındaki dengenin bozulması sonucunda gelişmektedir. Kalp ve damar hastalıkları ve tip II diyabetin etyolojisinde yer alan obezitenin ve kansere bağlı olarak gelişen ölümlerin en sık nedeni olan anoreksi-kaşeksinin başarılı bir şekilde tedavisi ve enerji dengesinin nasıl düzenlendiğinin iyi bir şekilde bilinmesiyle mümkündür. Enerji dengesinin sürdürülmesi, karşılıklı olarak etkileşen karmaşık ve dinamik bir süreçle sağlanmaktadır. Sindirim sistemi ve yağ dokusu gibi periferal dokulardan ve santral sinir sisteminin çeşitli bölgelerinden gelen uyarıların koordinasyonu ve uygun cevabın oluşturulmasında hipotalamus anahtar rol oynamaktadır. Hipotalamusa gelen uyarılara aracılık eden, dolayısıyla beslenme davranışının oluşmasına katılımı olan leptin, nöropeptid Y, oreksinler, proopiomelanokortin deriveleri, agouti-ilişkili protein (AgRP), kokain ve amfetamin regulated transkript, kolesistokinin, serotonin, noradrenalin, insülin, glukagon, kortikotropin salıverici faktör ve kortikosteroidler, girelin, galanin, galanin benzeri peptid, bombesin ve insandaki homoloğu gastrin salgılatıcı peptit, opiyatlar, kannabinoidler, nörotensin, nitrik oksid gibi çok sayıda nöromedyatör ve hormon ve TNF-α, IL1, IL6, silyar nörotrofik faktör gibi çok çeşitli sitokin tanımlanmıştır. Bu öğelerden her biri iştahın ve/veya enerji metabolizmasının belirleyici molekülleridir. Bu moleküllerin beslenme dışında rol oynadıkları diğer işlevlerin de bilinmesi, bu molekülleri hedef alan yeni ilaçların yan tesir profillerinin öngörülebilmesi açısından ayrıca önem taşımaktadır

Anahtar Kelimeler:

İştah, ilaç, şişmanlık, zayıflık, leptin, nöropeptid Y, sitokin

Feeding Behaviour: Pharmacological Target Molecules

Obesity and leanness are the results of the imbalance between energy intake and expenditure. Obesity has important roles in the etiology of tip II diabetes mellitus and cardiovascular diseases. On the other hand, anorexia-cachexia is the most frequent cause of cancer related deaths. So, it is important to know how energy balance is regulated so that these preventing or treating diseases can be prevented or treated. Energy homeostasis is maintained by complex and dynamic processes interacting with each other. Hypothalamus plays a key role in coordination and integration of stimuli from peripheral tissuses such as gastrointestinal system and fat tissue and from several regions of central nervous system. It also has important roles in appropriate adaptive response. Many neuromediator and hormons such as leptin, neuropeptide Y, orexins, derivates of proopiomelanocortin, agouti-related protein, cocaine and amphetamine-regulated transcript, cholecystokinin, serotonin, noradrenalin, insulin, glucagon and glucagon like peptide, corticotrophin releasing factor and corticosteroids, ghrelin, galanin and galanin like peptide, bombesin and its homolouge as gastrin releasing peptide in human, opioids, cannabinoids, neurotensin, nitric oxide and several cytokines such as TNF-α, IL1, IL6, ciliary neurotrophic factor mediate stimuli terminating in hypothalamus. So they contribute to feeding behaviour. It is also important to know the other actions of these molecules apart from their roles in feeding when predicting the side effect profiles of new drugs targeting these molecules

Keywords:

Appetite, obesity, leanness, leptin, neuropeptide Y, cytokine,

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