Post-translational modifications of Parkinson's disease-related proteins: Phosphorylation, SUMOylation and Ubiquitination.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons in the nigrostriatal pathway. The etiology of PD remains unclear and most cases are sporadic, however genetic mutations in more than 20 proteins have been shown to cause inherited forms of PD. Many of these proteins are linked to mitochondrial function, defects in which are a central characteristic of PD. Post-translational modifications (PTMs) allow rapid and reversible control over protein function. Largely focussing on mitochondrial dysfunction in PD, here we review findings on the PTMs phosphorylation, SUMOylation and ubiquitination that have been shown to affect PD-related proteins.

Pramipexole, a Dopamine D2/D3 Receptor-Preferring Agonist, Prevents Experimental Autoimmune Encephalomyelitis Development in Mice.

Experimental autoimmune encephalomyelitis (EAE) is the most used animal model of multiple sclerosis (MS) for the development of new therapies. Dopamine receptors can modulate EAE and MS development, thus highlighting the potential use of dopaminergic agonists in the treatment of MS, which has been poorly explored. Herein, we hypothesized that pramipexole (PPX), a dopamine D2/D3 receptor-preferring agonist commonly used to treat Parkinson's disease (PD), would be a suitable therapeutic drug for EAE. Thus, we report the effects and the underlying mechanisms of action of PPX in the prevention of EAE. PPX (0.1 and 1 mg/kg) was administered intraperitoneally (i.p.) from day 0 to 40 post-immunization (p.i.). Our results showed that PPX 1 mg/kg prevented EAE development, abolishing EAE signs by blocking neuroinflammatory response, demyelination, and astroglial activation in spinal cord. Moreover, PPX inhibited the production of inflammatory cytokines, such as IL-17, IL-1ß, and TNF-α in peripheral lymphoid tissue. PPX was also able to restore basal levels of a number of EAE-induced effects in spinal cord and striatum, such as reactive oxygen species, glutathione peroxidase, parkin, and α-synuclein (α-syn). Thus, our findings highlight the usefulness of PPX in preventing EAE-induced motor symptoms, possibly by modulating immune cell responses, such as those found in MS and other T helper cell-mediated inflammatory diseases.

Physical Exercise Attenuates Experimental Autoimmune Encephalomyelitis by Inhibiting Peripheral Immune Response and Blood-Brain Barrier Disruption.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) caused by demyelination, immune cell infiltration, and axonal damage. Herein, we sought to investigate the influence of physical exercise on mice experimental autoimmune encephalomyelitis (EAE), a reported MS model. Data show that both strength and endurance training protocols consistently prevented clinical signs of EAE and decreased oxidative stress, an effect which was likely due to improving genomic antioxidant defense-nuclear factor erythroid 2-related factor (Nrf2)/antioxidant response elements (ARE) pathway-in the CNS. In addition, physical exercise inhibited the production of pro-inflammatory cytokines interferon (IFN)-γ, interleukin (IL)-17, and IL-1ß in the spinal cord of mice with EAE. Of note, spleen cells obtained from strength training group incubated with MOG35-55 showed a significant upregulation of CD25 and IL-10 levels, with a decrease of IL-6, MCP-1, and tumor necrosis factor (TNF)-α production, mainly, during acute and chronic phase of EAE. Moreover, these immunomodulatory effects of exercise were associated with reduced expression of adhesion molecules, especially of platelet and endothelial cell adhesion molecule 1 (PECAM-1). Finally, physical exercise also restored the expression of tight junctions in spinal cord. Together, these results demonstrate that mild/moderate physical exercise, when performed regularly in mice, consistently attenuates the progression and pathological hallmarks of EAE, thereby representing an important non-pharmacological intervention for the improvement of immune-mediated diseases such as MS. Graphical Abstract Schematic diagram illustrating the beneficial effects of physical exercise during experimental model of MS. Physical exercise, especially strength (ST) and endurance (ET) training protocols, inhibits the development and progression of disease, measured by the mean maximal clinical score (1.5 and 1.0, respectively), with inhibition of 30 % and 50 %, respectively, based on the AUC, compared with EAEuntreated group. In addition, ST and ET decreased oxidative stress, possibly, through genomic antioxidant defense, Nrf2-Keap1 signaling pathway, in the CNS. Physical exercise inhibited the production of inflammatory cytokines, such as IFN-γ, IL-17 and IL-1ß in the spinal cord after EAE induction, as well as spleen cells obtained from ST group showed a significant upregulation of regulatory T cell markers, such as CD25 and IL-10 levels, and blocked IL-6, MCP-1 and TNF-α production, mainly, during acute and chronic phase of EAE. Finally, these immunomodulatory effects of exercise were associated with inhibition of adhesion molecules and reestablishment of tight junctions expression in spinal cord tissue, thereby limiting BBB permeability and transmigration of autoreactive T cells to the CNS. NO, nitric oxide; GPx, glutathione peroxidase, GSH, glutathione; Nrf2, nuclear factor (erythroid-derived 2)-like 2; CNS, central nervous system; BBB, blood-brain barrier; IFN-g, interferon-gamma; IL-17, interleukin 17; IL-1b, interleukin-1beta.

Pharmacological evidence favouring the traditional use of the root bark of Condalia buxifolia Reissek in the relief of pain and inflammation in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: The Condalia buxifolia root bark infusion is used in traditional medicine in Brazil as antipyretic, anti-inflammatory and against dysentery. This study was designed to investigate whether the methanolic extract of the root bark of Condalia buxifolia (MECb) exhibits antinociceptive and anti-inflammatory effects in mice. Furthermore, also was investigated the involvement of glutamatergic and opioidergic system in the antinociceptive effect induced by MECb. MATERIALS AND METHODS: The antinociceptive and anti-inflammatory effects of intra-gastric gavage (i.g.) administered MECb (10-300 mg/kg) were evaluated in mice subjected to chemical (formalin, acetic-acid, glutamate) or thermal (hot plate) models of pain. The involvement of opioid system in the antinociceptive effect of the MECb was investigated in formalin test. Furthermore, a nonspecific effect of MECb was evaluated by measuring locomotor activity and exploratory behavior in open field test. Finally, was performed a phytochemical analysis of MECb. RESULTS: The phytochemical analysis of MECb was performed through HPLC analysis showing that the alkaloid Condaline-A is the main constituent. The intragastric administration of MECb (100-300 mg/kg) significantly inhibited the nociception caused by acetic acid (48 ± 2%), inflammatory phase (49 ± 3%) and paw edema (32 ± 6) caused by formalin, and MECb (100mg/kg, i.g.) also inhibited nociception caused by glutamate (41 ± 7%). In addition, MECb (100-300 mg/kg, i.g.) increased the paw withdrawal latency in hot-plate test, without affecting the locomotor activity and exploratory behavior in open field test. Finally, the antinociceptive effects of MECb (100mg/kg, i.g.) were significantly reversed by naloxone (1mg/kg, i.p.) in the formalin test. CONCLUSION: These data show, for the first time, that MECb has significant antinociceptive and anti-inflammatory effects, which appear to be related to the inhibition of the glutamatergic system and the activation of opioid mechanism, besides present central effects. These results support the use of Condalia buxifolia in traditional medicine and demonstrate that this plant has therapeutic potential for the development of phytomedicines with antinociceptive and anti-inflammatory properties.