VOLUMETRIJSKA ANALIZA LIPIDNIH KAPI U LIMFOCITIMA BOLESNIKA SA TIP 2 DIJABETES MELITUSOM I HIPERLIPIDEMIJOM
Sažetak
Uvod: Tip 2 dijabetes melitus (T2DM) je hronični metabolički poremećaj kojeg karakteriše neadekvatna homeostaza glukoze. Jedna od uobičajenih pojava kod T2DM je dijabetska dislipidemija. Lipidne kapi imaju ulogu u skladištenju lipida u ćeliji, te se kao takve nalaze u centru homeostaze lipida i energije. Lipolizozomi predstavljaju ćelijske organele koje imaju strukturu lipidnih kapi okruženih membranom. Lipofagija je jedan od selektivnih oblika autofagije u kome dolazi do razgradnje lipidnih kapi, što predstavlja značajan mehanizam regulacije homeostaze lipidnih kapi.
Cilj rada: Ciljevi našeg istraživanja bili su analiza zapreminskog udela lipidnih kapi, autofagijskih vezikula sa lipidnim kapima (lipofaga), kao i lipolizozoma u limfocitima bolesnika sa T2DM i hiperlipidemijom.
Materijal i metode: Iz krvi dobijene od bolesnika sa T2DM i hiperlipidemijom i od zdravih osoba izolovane su mononuklearne ćelije koje su potom fiksirane u glutaraldehidu i postfiksirane u 1% rastvoru osmijum tetroksida. Nakon kontrastiranja u 4,7% rastvoru uranilacetata, uzorci su kalupljeni u epoksi smolama, a potom sečeni na ultramikrotomu. Dobijeni ultratanki isečci su ponovo kontrastirani i zatim analizirani na transmisionom elektronskom mikroskopu. Zapreminski udeo lipidnih kapi, lipofaga i lipolizozoma je određivan primenom dvostruke „coherent point“ mrežice sa tačkama u dve različite gustine.
Rezultati: Zapreminski udeo lipidnih kapi i lipofaga nije se značajno razlikovao u limfocitima bolesnika sa T2DM i hiperlipidemijom i zdravih ispitanika, dok je zapreminski udeo lipolizozoma bio statistički značajno veći u limfocitima bolesnika u odnosu na zdrave ispitanike (p < 0,05).
Zaključak: Povećan zapreminski udeo lipolizozoma otkriven u limfocitima bolesnika sa T2DM i hiperlipidemijom može govoriti u prilog pojačanoj aktivnosti ovih organela, a samim tim i povećanog lipidnog metabolizma u ćelijama kod ovih bolesnika.
Reference
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