lrrk2-in1 and Disease-Models--Animal

When Zika virus emerged as a public health emergency there were no drugs or vaccines approved for its prevention or treatment. We used a high-throughput screen for Zika virus protease inhibitors to identify several inhibitors of Zika virus infection. We expressed the NS2B-NS3 Zika virus protease and conducted a biochemical screen for small-molecule inhibitors. A quantitative structure-activity relationship model was employed to virtually screen ∼138,000 compounds, which increased the identification of active compounds, while decreasing screening time and resources. Candidate inhibitors were validated in several viral infection assays. Small molecules with favorable clinical profiles, especially the five-lipoxygenase-activating protein inhibitor, MK-591, inhibited the Zika virus protease and infection in neural stem cells. Members of the tetracycline family of antibiotics were more potent inhibitors of Zika virus infection than the protease, suggesting they may have multiple mechanisms of action. The most potent tetracycline, methacycline, reduced the amount of Zika virus present in the brain and the severity of Zika virus-induced motor deficits in an immunocompetent mouse model. As Food and Drug Administration-approved drugs, the tetracyclines could be quickly translated to the clinic. The compounds identified through our screening paradigm have the potential to be used as prophylactics for patients traveling to endemic regions or for the treatment of the neurological complications of Zika virus infection.

Topics: Animals; Antiviral Agents; Artificial Intelligence; Chlorocebus aethiops; Disease Models, Animal; Drug Evaluation, Preclinical; High-Throughput Screening Assays; Immunocompetence; Inhibitory Concentration 50; Methacycline; Mice, Inbred C57BL; Protease Inhibitors; Quantitative Structure-Activity Relationship; Small Molecule Libraries; Vero Cells; Zika Virus; Zika Virus Infection

Overexposure to manganese (Mn) leads to manganism and neurotoxicity induced by Mn is the focus of recent research. Microglia play a vital role in Mn-induced neurotoxicity, and our previous studies firstly showed that Mn could stimulate activation of microglia, leading to the neuroinflammation, and inhibition of microglial inflammation effectively attenuated Mn-induced death of dopamine neurons. However, the detailed mechanism of manganese-induced neuroinflammation is still unclear. Leucine rich repeat kinase 2 (LRRK2) is a key molecule in the pathogenesis of many neurodegenerative disorders. Recent studies have indicated that LRRK2, which is highly expressed in microglia, plays a specific role in microglia and autophagy process. In this paper, we try to find the effect of LRRK2 on Mn-triggered neuroinflammation and its possible mechanism in vivo and in vitro. By establishing a Mn exposure animal model, our studies found that Mn exposure could induce dopaminergic neurons damage and activate microglia. Activated microglia triggered neuroinflammation by releasing multiple inflammatory cytokines, and the expression of LRRK2 was upregulated in vivo and in vitro. We also found that Mn exposure induced autophagy dysfunction in vivo and in vitro. Next, we used LRRK2 siRNA and LRRK2-IN-1 to inhibit the expression of LRRK2, and found that inhibition of LRRK2 could not only decrease the expression of inflammatory cytokines, but also recover autophagic function of microglia. Our investigation not only reveals the role of LRRK2 in Mn-induced neuroinflammation but also sheds light on the prevention and protection of manganism.

Topics: Animals; Autophagy; Benzodiazepinones; Disease Models, Animal; Inflammation; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Male; Manganese; Mice, Inbred C57BL; Microglia; Nervous System; Pyrimidines; RNA, Small Interfering; Up-Regulation

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most prevalent cause of familial and sporadic Parkinson's disease (PD). Because most pathogenic LRRK2 mutations result in enhanced kinase activity, it suggests that LRRK2 inhibitors may serve as a potential treatment for PD. To evaluate whether LRRK2 inhibitors are effective therapies for PD, it is crucial to know whether LRRK2 inhibitors will affect dopaminergic (DAergic) neurotransmission. However, to date, there is no study to investigate the impact of LRRK2 inhibitors on DAergic neurotransmission.. To address this gap in knowledge, we examined the effects of three types of LRRK2 inhibitors (LRRK2-IN-1, GSK2578215A, and GNE-7915) on dopamine (DA) release in the dorsal striatum using fast-scan cyclic voltammetry and DA neuron firing in the substantia nigra pars compacta (SNpc) using patch clamp in mouse brain slices.. We found that LRRK2-IN-1 at a concentration higher than 1 μM causes off-target effects and decreases DA release, whereas GSK2578215A and GNE-7915 do not. All three inhibitors at 1 μM have no effect on DA release and DA neuron firing rate. We have further assessed the effects of the inhibitors in two preclinical LRRK2 mouse models (i.e., BAC transgenic hG2019S and hR1441G) and demonstrated that GNE-7915 enhances DA release and synaptic vesicle mobilization/recycling.. GNE-7915 can be validated for further therapeutic development for PD.

Topics: Aminopyridines; Animals; Benzamides; Benzodiazepinones; Biophysical Phenomena; Corpus Striatum; Disease Models, Animal; Dopamine; Dose-Response Relationship, Drug; Electric Stimulation; In Vitro Techniques; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Male; Mice; Mice, Transgenic; Morpholines; Mutation; Parkinson Disease; Patch-Clamp Techniques; Pyrimidines; Substantia Nigra