Dopamine Released from TiO₂ Semicrystalline Lattice Implants Attenuates Motor Symptoms in Rats Treated with 6-Hydroxydopamine

Abstract

The motor dysfunction featured by patients aggrieved by Parkinson’s disease (PD) results from the reduction of dopamine (DA) availability in the caudate nucleus (CN). Restituting CN DA levels is therefore essential to ameliorate PD motor deficits. In this regard, nanotechnology may offer solutions to restore CN DA availability. DA, however, can be rapidly oxidized into toxic compounds if made available in situ, unprotected. Then, we tested whether a semicrystalline TiO 2 lattice, implanted into the CN of 6-hydroxydopamine (6-OHDA)-lesioned, hemiparkinsonian rats, was able to release DA during a time window sufficient to attenuate motor symptoms while protecting it from the ongoing oxidation. Accordingly, implanted semicrystalline TiO 2 lattices released incremental amounts of DA into the CN of lesioned rats. Motor symptoms were already attenuated by the 1st month and significantly reduced 2 months after implantation. These effects were specific since TiO 2 lattices alone did not modify motor symptoms in lesioned rats. DA-unloaded or -loaded TiO 2 lattices did not produce obvious symptoms of systemic or neurological toxicity nor significantly increased CN lipid peroxidation in implanted, lesioned rats at the time of sacrifice. Our results thus support that loaded TiO 2 lattices are capable of releasing DA while protecting it from the ongoing oxidation when implanted into the brain. Their implantation does not cause noticeable systemic or local toxicity. On the contrary, they attenuated motor symptoms in hemiparkinsonian rats.

Mediating the Fate of Cancer Cell Uptake: Dual-Targeted Magnetic Nanovectors with Biotin and Folate Surface Ligands

“…In comparison to free dopamine molecules, the dopa–Fe 3 O 4 conjugates showed a dominant shift in all peaks (Figure S2), confirming the attachment of dopamine on the surface of NPs. The pure dopamine (Figure S2) showed bands due to C–O (1175 cm –1 ), C–H 2 (1175 cm –1 ), C–N (1320, 1340 cm –1 ), CO (1578 cm –1 ) N–H (1616 cm –1 ), O–H, and N–H (2936–3336 cm –1 ) . The FTIR spectrum of pure folic acid showed −OH stretching vibrations at the 3543, 3420, and 3317 cm –1 regions (Figure A, red) .…”

Nanomedicine in the Face of Parkinson’s Disease: From Drug Delivery Systems to Nanozymes

“…In this study, TiO 2 -DA complexes synthesized by the sol-gel method were implanted on the caudate nucleus of unilaterally lesioned rats, significantly recovering motor crossing and rearing behaviours. Subsequent studies identified that the oxidation process of DA was delayed for up to 30 days [ 158 , 159 , 160 ]; similarly, DA release from the device in vivo was corroborated up to 360 days post-implantation [ 161 ]. Other DA stabilization approaches on TiO 2 have opted for the design of nanohybrid organic-inorganic composites, in which CS-DA composites were coated with titania [ 162 ].…”

Gold-Modified Molecularly Imprinted N-Methacryloyl-(l)-phenylalanine-containing Electrodes for Electrochemical Detection of Dopamine

“…Molecularly imprinted polymer (MIP) electrodes indicate one of the main sensors used to detect many biochemical compounds in a highly sensitive and selective approach, which has various applications in many criteria in voltametric detection research [17]. MIP electrodes demonstrated that they might be investigated for their ability to detect DA with high accuracy despite existing biological compound interferences [18].…”