Indol 3-carbinol

Este o substanta produsa de plante din familia Crucifere, in special de catre cele din genul Brassica (varza, broccoli, conopida, varza de Brussel, etc.). In organismul nostru indol 3-carbinolul (prescurtat I3C) este transformat intr-o serie de compusi  responsabili pentru efectele sale biologice. De interes pentru noi sunt efectele antitumorale, pe care le vom descrie in continuare.

S-a demonstrat prin studii de laborator si pe animale ca I3C inhiba proliferarea mai multor tipuri de celule canceroase: de prostata, san, endometriale, de colon.

Prin studiile sale Hong si echipa sa au aratat ca I3C inhiba sinteza de ADN si proliferarea atat a celulelor ER (estrogen receptor) pozitive cat si a celor negative din cancerul de san. In cadrul acestor experimente s-a observat condensarea cromatinei celulelor canceroase, fragmentarea ADN-ului si externalizarea fosfatidilserinelor, ceea ce constituie semne pentru apoptoza celulelor respective. Mai mult, s-a observat ca I3C a scazut cantitatea de proteina antiapoptotica Bcl-2. Aceste date  dovedesc faptul ca I3C induce apoptoza celulelor tumorale din cancerul de san independent de statusul receptorilor de estrogen.

In acelasi timp, in cazul cancerului endometrial Leong a dovedit ca inhibitia proliferarii celulelor canceroase se datoreaza unui mecanism in care sunt implicati si receptorii pentru estrogeni, mecanism care duce la cresterea expresiei TGF-alfa (transforming growth factor).

In cazul celulelor colonice, Bonnesen a descoperit ca I3C induce apoptoza celulelor tumorale dar confera protectie ADN-ului celulelor sanatoase.

Mai multe studii au aratat ca I3C duce la blocarea celulelor tumorale in faza G1 a ciclului celular, ceea ce duce la stoparea dezvoltarii acelor celule. Experimentele au fost facute pe celule canceroase prostatice si de san, atat ER pozitive cat si negative, rezultatele fiind asemanatoare.

Un alt efect benefic al indol 3-carbinol-ului este acela de a inlatura rezistenta pe care o dezvolta unele tipuri de celule canceroase fata de chemoterapice. De aceasta rezistenta este responsabila glicoproteina P, codificata de gena mdr si care functioneaza ca transportor multimedicament. Prin cercetarile sale, Arora a aratat ca I3C reuseste sa moduleze expresia glicoproteinei P in celulele leucemice rezistente la diverse chimioterapice facandu-le sensibile la acele medicamente.

Bibliografie:

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