In situ continuous Dopa supply by responsive artificial enzyme for the treatment of Parkinson's disease

Enzyme-Programmed Self-Assembly of Nanoparticles

Nanoparticles are a hot topic in the field of nanomaterial research due to their excellent physical and chemical properties. In recent years, DNA-directed nanoparticle self-assembly technology has been widely applied to the development of numerous complex nanoparticle superstructures. Due to the inherent stability and surface electric repulsion of nanoparticles, it is difficult to make nanoparticle superstructures respond to molecular signals in the external environment. In fact, enzyme-programmed molecular systems are developed to allow diverse functions, including logical operations, signal amplification, and dynamic assembly control. Therefore, combining enzyme-controlled DNA systems may endow nanoparticle assembly systems with more flexibility in program design, allowing them to respond to a variety of external signals. In this review, we summarize the basic principles of enzyme-controlled DNA/nanoparticle self-assembly and introduce its applications in heavy metal detection, gene expression, proteins inside living cells, cancer cell therapy, and drug delivery. With the continuous development of new nanoparticle materials and the increasing functionality of enzyme DNA circuits, enzyme-directed DNA/nanoparticle self-assembled probe technology is expected to see significant future development.

Tapered cross-linked ZnO nanowire bundle arrays on three-dimensional graphene foam for highly sensitive electrochemical detection of levodopa

It is crucial to accurately and rapidly monitor the levodopa (LD) concentration for accurate classification and treatment of dyskinesia in Parkinson's disease. In this paper, 3D graphene foam (GF) with a highly conductive network is obtained by chemical vapor deposition. 3D GF serves as the substrate for hydrothermal in situ growth of tapered cross-linked ZnO nanowire bundle arrays (ZnO NWBAs), enabling the development of a highly sensitive detection platform for LD. The formation mechanism of a tapered cross-linked ZnO nanowire bundle arrays on 3D GF is put forward. The integration of 3D GF and ZnO NWBAs can accelerate the electron transfer rate and increase the contact area with biomolecules, resulting in high electrochemical properties. The electrode composed of ZnO NWBAs on 3D GF exhibits significant sensitivity (1.66 µA·µM-1·cm-2) for LD detection in the concentration range 0-60 µM. The electrode is able to rapidly and specifically determine LD in mixed AA or UA solution. The selectivity mechanism of the electrode is also explained by the bandgap model. Furthermore, the successful detection of LD in serum demonstrates the practicality of the electrode and its great potential for clinical application.

Quantum-level machine learning calculations of Levodopa

Many drug molecules contain functional groups, resulting in a torsional barrier corresponding to rotation around the bond linking the fragments. In medicinal chemistry and pharmaceutical sciences, inclusive of drug design studies, the exact calculation of the potential energy surface (PES) of these molecular torsions is extremely important and precious. Machine learning (ML), including deep learning (DL), is currently one of the most rapidly evolving tools in computer-aided drug discovery and molecular simulations. In this work, we used ANI-1x neural network potential as a quantum-level ML to predict the PESs of the L-3,4-dihydroxyphenylalanine (Levodopa) antiparkinsonian drug molecule. The electronic energies and structural parameters calculated by density functional theory (DFT) using the wB97X method and all possible Pople's basis sets indicated the 6-31G(d) basis set, when used with the wB97X functional, exhibits behavior similar to that of the ANI-1x model. The vibrational frequencies investigation showed a linear correlation between DFT and ML data. All ANI-1x calculations were completed quickly in a very short computing time. From this perspective, we expect the ANI-1x dataset applied in this work to be appreciably efficient and effective in computational structure-based drug design studies.

Metastable FeSe2 nanosheets as a one-for-all platform for stepwise synergistic tumor therapy

The urgent need to curb the rampant rise in cancer has impelled the rapid development of nanomedicine. Under the above issue, transition metal compounds have received special attention considering their physicochemical and biochemical properties. However, how to take full advantage of the valuable characteristics of nanomaterials based on their spatial structures and chemical components for synergistic tumor therapy is a worthwhile exploration. In this work, a tailored two-dimensional (2D) FeSe2 nanosheet (NS) platform is proposed, which integrates enzyme activity and drug efficacy through the regulation of itsstability. Specifically, metastable FeSe2 NSs can serve as dual nanozymes in an intact state, depleting GSH and increasing ROS to induce oxidative stress in the tumor microenvironment (TME). With the gradual degradation of the FeSe2 in TME, its degraded products can amplify the Fenton reaction and GSH consumption, enhance the expression of inflammatory factors, and achieve effective near-infrared (NIR)-light irradiation-enhanced synergistic photothermal therapy (PTT) and chemodynamic therapy (CDT). Our exploration further confirmed such a strategy that may integrate carrier activity and drug action into a metastable nanoplatform for tumor synergistic therapy. These results prompt the consideration of the rational design of a one-for-all carrier that can exhibit multifunctional properties and nanomedicine efficacy for versatile therapeutic applications in the future.

Dopamine synthesis and transport: current and novel therapeutics for parkinsonisms

Parkinsonism is the primary type of movement disorder in adults, encompassing a set of clinical symptoms, including rigidity, tremors, dystonia, bradykinesia, and postural instability. These symptoms are primarily caused by a deficiency in dopamine (DA), an essential neurotransmitter in the brain. Currently, the DA precursor levodopa (synthetic L-DOPA) is the standard medication to treat DA deficiency, but it only addresses symptoms rather than provides a cure. In this review, we provide an overview of disorders associated with DA dysregulation and deficiency, particularly Parkinson's disease and rare inherited disorders leading predominantly to dystonia and/or parkinsonism, even in childhood. Although levodopa is relatively effective for the management of motor dysfunctions, it is less effective for severe forms of parkinsonism and is also associated with side effects and a loss of efficacy over time. We present ongoing efforts to reinforce the effect of levodopa and to develop innovative therapies that target the underlying pathogenic mechanisms affecting DA synthesis and transport, increasing neurotransmission through disease-modifying approaches, such as cell-based therapies, nucleic acid- and protein-based biologics, and small molecules.

Improving Magnetic Resonance Imaging and Chemodynamic Therapy Properties via Tuning the Fe(II)/Fe(III) Ratio in Hydrophilic Single-Atom Nanobowls

We developed an intrinsic hydrophilic single-atom iron nanobowl (Fe-SANB) for magnetic resonance imaging (MRI)-guided tumor microenvironment-triggered cancer therapy. Benefiting from the sufficient exposure of Fe single atoms and the intrinsic hydrophilicity of the bowl-shaped structure, the Fe-SANBs exhibited a superior performance for T1-weighted MRI with an r1 value of 11.48 mM-1 s-1, which is 3-fold higher than that of the commercial Gd-DTPA (r1 = 3.72 mM-1 s-1). After further coembedding Gd single atoms in the nanobowls, the r1 value can be greatly improved to 19.54 mM-1 s-1. In tumor microenvironment (TME), the Fe-SANBs can trigger pH-induced Fenton-like activity to generate highly toxic hydroxyl radicals for high-efficiency chemodynamic therapy (CDT). Both the MRI and CDT efficiency of these nanobowls can be optimized by tuning the ratio of Fe(II)/Fe(III) in the Fe-SANBs via controlling the calcination temperature. Furthermore, the generation of •OH at the tumor site can be accelerated via the photothermal effect of Fe-SANBs, thus promoting CDT efficacy. Both in vitro and in vivo results confirmed that our nanoplatform exhibited high T1-weighted MRI contrast, robust biocompatibility, and satisfactory tumor treatment, providing a potential nanoplatform for MRI-guided TME-triggered precise cancer therapy.

Enhancing Neuroprotection in Mouse Model of Parkinson's Disease through Protein Nanosystem Conjugation with ApoE Peptide for miR-124 Delivery

Parkinson's disease (PD) affects millions of people's lives worldwide. The main pathogenesis of PD is dopaminergic neuron necrosis and neuroinflammation mediated by activated microglia cells. In recent years, the anti-inflammatory ability and neuroprotective effects of miR-124 in PD models were well proved, but the in vivo delivery of miR-124 remains challenging. Herein, we report a protein nanosystem modified with a brain-targeting peptide ApoE that could efficiently deliver miR-124 across the blood-brain barrier (BBB). This nanosystem showed good cell viability on brain endothelial cells and microglia cells, and administration of this nanosystem significantly decreased the neuroinflammation and dopaminergic neuron loss, as well as recovered parts of neurobehavioral deficits. This ApoE peptide-based protein nanosystem holds great promise for the delivery of RNA therapeutics to the brain and for realizing neuron protection in PD treatment.