Tissue specific expression of genes encoding cholesterol transporters ABCA1 and ABCG1 as well as genes encoding the most important transcriptional regulators of adipogenesis - LXRa, LXRb, PPARg and RORa has been investigated in intraabdominal adipose tissue (IAT) samples.A direct correlation between the content of ABCA1 and ABCG1 proteins with RORa protein level (r=0.480, p<0.05; r=0.435, p<0.05, respectively) suggests the role of the transcription factor RORa in the regulation of IAT ABCA1 and ABCG1 protein levels. ABCA1 and ABCG1 gene expression positively correlated with obesity indicators such as body mass index (BMI) (r=0.522, p=0.004; r=0.594, p=0.001, respectively) and waist circumference (r=0.403, p=0.033; r=0.474, p=0.013, respectively). The development of obesity is associated with decreased IAT levels of RORa and LXRb mRNA (p=0.016 and p=0.002, respectively). These data suggest that the nuclear factor RORa can play a significant role in the regulation of cholesterol metabolism and control IAT expression of ABCA1 and ABCG1, while the level of IAT LXRb gene expression may be an important factor associated with the development of obesity.
Izuchena tkanespetsifichnaia ékspressiia genov transporterov kholesterina ABCA1 i ABCG1, a takzhe genov, kodiruiushchikh naibolee vazhnye transkriptsionnye reguliatory adipogeneza – LXRa, LXRb, PPARg i RORa, v intraabdominal'noĭ zhirovoĭ tkani (IZhT) u lits bez izbytochnogo vesa i lits s ozhireniem. Pokazana priamaia korreliatsiia soderzhaniia belkov ABCA1 i ABCG1 v IZhT s urovnem belka RORa (r=0,480, p<0,05; r=0,435, p<0,05 sootvetstvenno), chto pozvoliaet predpolozhit' uchastie transkriptsionnogo faktora RORa v reguliatsii urovnia belkov ABCA1 i ABCG1 v IZhT. Pri étom ékspressiia genov ABCA1 i ABCG1 polozhitel'no korreliruet s takimi pokazateliami, kak indeks massy tela (IMT) (r=0,522, p=0,004; r=0,594, p=0,001 sootvetstvenno) i obkhvat talii (OT) (r=0,403, p=0,033; r=0,474, p=0,013 sootvetstvenno). Razvitie ozhireniia takzhe assotsiirovano so snizheniem urovnia mRNK RORa i LXRb (p=0,016 i p=0,002 sootvetstvenno) v IZhT. Predpolagaetsia, chto iadernyĭ faktor RORa mozhet igrat' znachimuiu rol' v reguliatsii obmena kholesterina i kontrole ékspressii genov ABCA1 i ABCG1 v IZhT, a uroven' ékspressii gena LXRb v IZhT mozhet byt' vazhnym faktorom, assotsiirovannym s razvitiem ozhireniia.
Keywords: ABCA1 and ABCG1 transporters; gene expression; intraabdominal adipose tissue; transcriptional regulators.