Poster Topical Area: Dietary Bioactive Components
Location: Hall D
Poster Board Number: 306
Objectives: Prolonged hyperglycemia in diabetic nephropathy causes glomerular podocyte damage that can lead to podocyte loss and foot process effacement. Eucalyptol (1,8-cineole) is a natural organic essential oil which is a monoterpenoid present in eucalyptus oil with anti-inflammatory and antioxidant properties. This study investigated the renoprotective effects of eucalyptol on podocyte slit junctions and foot process effacement under diabetic ambience.
Methods: Immotalized mouse podocytes were incubated in media containing 33 mM glucose or 100 µg/ml AGE for 4 d in the presence of 1-20 μM eucalyptol. Antibodies of nephrin, podocin, integrin β1, α-actinin-4, CD2AP, advanced glycation end products (AGEs) and receptor for AGEs (RAGE) were used for Western blot. The in vivo animal model was orally administrated with 10 mg/kg of eucalyptol. Extracts of tissues cut down in 5 µM thickness were Western-blotted or immunohistochemistry. Kidney tissue sections were observed with transmission electron microscopy (TEM).
Results: Eucalyptol enhanced expression of the podocyte slit diaphragm proteins of nephrin, podocin and integrin β1 down-regulated by glucose stimulation. In addition, eucalyptol restored the expression of CD2AP, FAT1 and α-actinin-4. The RAGE induction was elevated by exposure of podocytes to high glucose and AGEs, which was reduced by eucalyptol in a dose-dependent manner. TEM revealed that podocyte foot process effacement occurred in diabetic mouse glomeruli. However, oral administration of eucalyptol improved foot process effacement of diabetic podocytes through inhibiting loss of glomerular slit junction proteins of CD2AP and α-actinin-4. Increased induction of AGEs and histological alterations in diabetic kidneys tissue declined in the eucalyptol-treated mice, evidenced by immunohistostaining and PAS staining.
Conclusions: These results demonstrated that eucalyptol maintained normal structures of podocyte foot process and slit diaphragm.Therefore, eucalyptol may be a potent renoprotective agent combating diabetes-associated podocyte dysfunction and maintaining glomerular filtration barrier.
This work was supported by the National Research Foundation of Korea grant funded by the Korea government (NRF-2017R1A6A3A04011473).
Dong Yeon Kim
master course student
Chuncheon-si, Kangwon-do, Republic of Korea