Circ_0003611 acts as a miR-885-5p sponge to aggravate the amyloid-β-induced neuronal injury in Alzheimer's disease.

Alzheimer's disease (AD) is a chronic degenerative disease in the central nervous system and circular RNAs (circRNAs) are identified as essential regulators in AD. The current research was designed for exploration of circ_0003611 in AD. Circ_0003611 was overexpressed in AD patients and Aβ-treated SK-N-SH cells. Aβ-induced apoptotic, inflammatory and oxidative damages were relieved after knockdown of circ_0003611. MiR-885-5p was validated as a miRNA target of circ_0003611. The protective function of circ_0003611 downregulation was achieved by releasing miR-885-5p in Aβ-treated SK-N-SH cells. KREMEN1 was a downstream gene of miR-885-5p. Overexpression of miR-885-5p attenuated the Aβ-triggered cell injury by reducing the KREMEN1 expression. KREMEN1 was regulated by circ_0003611 via sponging miR-885-5p in Aβ-treated SK-N-SH cells. These experimental data demonstrated that circ_0003611 enhanced the Aβ-induced neuronal cell injury in AD by serving as the miR-885-5p sponge to regulate the level of KREMEN1.