Aggregated forms of α-synuclein play a crucial role in the pathogenesis of synucleinopathies such as Parkinson’s disease (PD). However, the molecular mechanisms underlying the pathogenic effects of α-synuclein are not completely understood. Here we show that asparagine endopeptidase (AEP) cleaves human α-synuclein, triggers its aggregation and escalates its neurotoxicity, thus leading to dopaminergic neuronal loss and motor impairments in a mouse model. AEP is activated and cleaves human α-synuclein at N103 in an age-dependent manner. AEP is highly activated in human brains with PD, and it fragments α-synuclein, which is found aggregated in Lewy bodies. Overexpression of the AEP-cleaved α-synuclein1–103 fragment in the substantia nigra induces both dopaminergic neuronal loss and movement defects in mice. In contrast, inhibition of AEP-mediated cleavage of α-synuclein (wild type and A53T mutant) diminishes α-synuclein’s pathologic effects. Together, these findings support AEP’s role as a key mediator of α-synuclein-related etiopathological effects in PD.

This multimodal exercise training could improve motion function and benefit balance function in patients with Parkinson disease. The multimodal exercise training is easy to learn and practice.

Trigeminal neuralgia is a common disorder caused mainly by compression of the trigeminal nerve root by an overlying blood vessel. Pharmacotherapy and surgery are ineffective or unsuitable in many patients. Therefore, other therapeutic modalities have been tried, including injection of botulinum toxin type A (BTX-A). This study aims to systematically review the therapeutic efficacy and safety of BTX-A in trigeminal neuralgia. PubMed, EMBASE, Cochrane Library Clinical Trials and Web of Science from January 1966 to March 2013 were searched with the terms of “botulinum toxin” AND “trigeminal neuralgia”, and references of related articles were traced. Data on the efficacy and safety of BTX-A in this disorder were extracted and analyzed by at least 2 reviewers. Data for individual studies were reported, and pooled data were analyzed if appropriate. Five prospective studies and one double-blind, randomized, placebo-controlled study were identified. Response was achieved in approximately 70-100% of patients, and the mean pain intensity and frequency were reduced by approximately 60-100% at 4 weeks after treatment in most studies. Major adverse events were not reported. Available studies show BTX-A may be effective in treatment of trigeminal neuralgia. However, well-designed randomized, controlled, double-blinded trial is still lacking. Future BTX-A treatment studies on optimal dose, duration of the therapeutic efficacy, common AEs, and the time and indications for repeat injection would be promising.

Raynaud's phenomenon (RP), an episodic vasospasm of the peripheral arteries, is quite common in general population. The current therapies of RP are limited by efficacy, side effects, and polypharmacy concerns. Botulinum toxin type A (BTX-A) local injections have been reported for the treatment of RP, but the injection sites, concentration and dose of BTX-A were different from each other in previous trials. In addition, so far, there have been no reports concerning local injection of BTX-A in Asian RP patients. Ten patients with RP in China were included in this retrospective study. All the patients had intractable pain and were non-responsive to conservative and/or medical therapy. A patterned BTX-A injection was performed in RP patients, guided by ultrasonography. BTX-A was injected as 20 u/ml devoid of preservatives. Outcomes were measured by ultrasonography, surface temperature, visual analog scale (VAS) for clinical symptoms (pain, numbness, stiffness and swelling), and changes in ulcers or gangrene. Overall, a great improvement in artery flow velocity (P < 0.01), surface temperature (P < 0.01), ulcer and VAS for clinical symptoms, was observed after BTX-A local injection. Complications were very rarely found, and no patients complained of hand weakness and bruise. BTX-A patterned injection guided by ultrasonography might be a useful therapeutic tool in the management of intractable RP.

Brain cancer is a kind of tough carcinoma because the blood-brain barrier (BBB) remains a formidable obstacle in medicine. Curcumin (Cur) was determined to have anticancer potency on several kinds of carcinoma. However, its medical application was limited because of its poor bioavailability, unsatisfying dispersity and rapid metabolism in vivo. In this study, Cur was delivered by nanostructured lipid carriers (NLCs) for brain cancer treatment. The physiochemical characters of NLC-Cur were detected by using high-performance liquid chromatography, Transmission electron microscopy and photon correlation spectrum analyses. The cellular uptake and the anticancer efficiency were determined both in vitro and in vivo by flow cytometry detection, MTT assay, AO/EB, Annexin-V/PI, DCFDA and tumor-bearing mice. NLC-Cur was synthesized by using sol-gel method and with the size around 100 nm. After loaded in NLC, the IC 50 of NLC-Cur was 20 mg/mL, only one-fourth of the plain drug. The plasmid concentration of Cur was highly increased (6.4-folds) in mice via intraperitoneally after loaded with NLC. Furthermore, NLC-Cur enhanced the targeting effect of Cur to brain and tumor, which finally increased the inhibition efficiency of Cur from 19.5% to 82.3%. The FITC analysis confirmed that the inhibition effect mostly came from apoptosis, but not necrosis. The time depending cellular uptake, reactive oxygen species production, markedly increased bio-availability and tumor targeting effect played an important role in the efficacy of NLC-Cur. Our work indicated the medical application of NLC-Cur on brain cancer treatment, and also provided a novel method for new anticancer agents' development.

Background Glioblastoma (GBM) is a universally lethal tumor with frequently overexpressed or mutated epidermal growth factor receptor (EGFR). NADPH quinone oxidoreductase 1 (NQO1) and glutathione-S-transferase Pi 1 (GSTP1) are commonly upregulated in GBM. NQO1 and GSTP1 decrease the formation of reactive oxygen species (ROS), which mediates the oxidative stress and promotes GBM cell proliferation. Methods High-throughput screen was used for agents selectively active against GBM cells with EGFRvIII mutations. Co-crystal structures were revealed molecular details of target recognition. Pharmacological and gene knockdown/overexpression approaches were used to investigate the oxidative stress in vitro and in vivo. Results We identified a small molecular inhibitor, “MNPC,” that binds to both NQO1 and GSTP1 with high affinity and selectivity. MNPC inhibits NQO1 and GSTP1 enzymes and induces apoptosis in GBM, specifically inhibiting the growth of cell lines and primary GBM bearing the EGFRvIII mutation. Co-crystal structures between MNPC and NQO1, and molecular docking of MNPC with GSTP1 reveal that it binds the active sites and acts as a potent dual inhibitor. Inactivation of both NQO1 and GSTP1 with siRNA or MNPC results in imbalanced redox homeostasis, leading to apoptosis and mitigated cancer proliferation in vitro and in vivo. Conclusions Thus, MNPC, a dual inhibitor for both NQO1 and GSTP1, provides a novel lead compound for treating GBM via the exploitation of specific vulnerabilities created by mutant EGFR.

The main pathological feature of Parkinson's disease (PD) is the loss of dopaminergic neurons in the substantia nigra. In this study, we investigated the role of cannabinoid receptor 2 (CB2R) agonist AM1241 on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in a mouse model of PD. Upon treatment with AM1241, the decreased CB2R level in the PD mouse brain was reversed and the behavior score markedly elevated, accompanied with a dose-dependent increase of dopamine and serotonin. In addition, western blot assay and immunostaining results suggested that AM1241 significantly activated PI3K/Akt/MEK phosphorylation and increased the expression of Parkin and PINK1, both in the substantia nigra and hippocampus. The mRNA expression analysis further demonstrated that AM1241 increased expression of the CB2R and activated Parkin/PINK1 signaling pathways. Furthermore, the increased number of TH-positive cells in the substantia nigra indicated that AM1241 regenerated DA neurons in PD mice, and could therefore be a potential candidate for PD treatment. The clear co-localization of CB2R and DA neurons suggested that AM1241 targeted CB2R, thus also identifying a novel target for PD treatment. In conclusion, the selective CB2 agonist AM1241 has a significant therapeutic effect on PD mice and resulted in regeneration of DA neurons following MPTP-induced neurotoxicity. The possible mechanisms underlying the neurogenesis effect of AM1241 might be the induction of CB2R expression and an increase in phosphorylation of the PI3K/AKT signaling pathway.

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