RESUMEN

Parkinson's disease (PD) poses a formidable challenge in neurology, marked by progressive neuronal loss in the substantia nigra. Despite extensive investigations, understanding PD's pathophysiology remains elusive, with no effective therapeutic intervention identified to alter its course. Oxyphylla A (OPA), a natural compound extracted from Alpinia oxyphylla, exhibits promise in experimental models of various neurodegenerative disorders (ND), notably through novel mechanisms like α-synuclein degradation. The purpose of this investigation was to explore the neuroprotective potential of OPA on 6-hydroxydopamine (6-OHDA)-induced neurotoxicity in PD models, with a focus on mitochondrial functions. Additionally, potential OPA targets for neuroprotection were explored. PC12 cells and C57BL/6 mice were lesioned with 6-OHDA as PD models. Impaired mitochondrial membrane potential (Δψm) was assessed using JC-1 staining. The oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were also detected to evaluate mitochondrial function and glucose metabolism in PC12 cells. Behavioral analysis and immunohistochemistry were performed to evaluate pathological lesions in the mouse brain. Moreover, bioinformatics tools predicted OPA targets. OPA restored cellular energy metabolism and mitochondrial biogenesis, preserving Δψm in 6-OHDA-induced neuronal damage. Pre-treatment mitigated loss of tyrosine hydroxylase (TH)-positive neurons in the substantia nigra and striatal dopaminergic fibers, restoring dopamine levels and ameliorating motor deficits in PD mice. Mechanistically, OPA may activate PKA/Akt/GSK-3ß and CREB/PGC-1α/NRF-1/TFAM signaling cascades. Bioinformatics analysis identified potential OPA targets, including CTNNB1, ESR1, MAPK1, MAPK14, and SRC. OPA, derived from Alpinia oxyphylla, exhibited promising neuroprotective activity against PD through addressing mitochondrial dysfunction, suggesting its potential as a multi-targeted therapeutic for PD.

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor symptoms like tremors and bradykinesia. PD's pathology involves the aggregation of α-synuclein and loss of dopaminergic neurons, leading to altered neural oscillations in the cortico-basal ganglia-thalamic network. Despite extensive research, the relationship between the motor symptoms of PD and transient changes in brain oscillations before and after motor tasks in different brain regions remain unclear. This study aimed to investigate neural oscillations in both healthy and PD model mice using local field potential (LFP) recordings from multiple brain regions during rest and locomotion. The histological evaluation confirmed the significant dopaminergic neuron loss in the injection side in 6-OHDA lesioned mice. Behavioral tests showed motor deficits in these mice, including impaired coordination and increased forelimb asymmetry. The LFP analysis revealed increased delta, theta, alpha, beta, and gamma band activity in 6-OHDA lesioned mice during movement, with significant increases in multiple brain regions, including the primary motor cortex (M1), caudate-putamen (CPu), subthalamic nucleus (STN), substantia nigra pars compacta (SNc), and pedunculopontine nucleus (PPN). Taken together, these results show that the motor symptoms of PD are accompanied by significant transient increases in brain oscillations, especially in the gamma band. This study provides potential biomarkers for early diagnosis and therapeutic evaluation by elucidating the relationship between specific neural oscillations and motor deficits in PD.

Asunto(s)

Modelos Animales de Enfermedad , Enfermedad de Parkinson , Animales , Ratones , Enfermedad de Parkinson/fisiopatología , Masculino , Oxidopamina , Ratones Endogámicos C57BL , Corteza Motora/fisiopatología , Corteza Motora/metabolismo , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Encéfalo/fisiopatología , Encéfalo/patología , Encéfalo/metabolismo , Ondas Encefálicas , Actividad Motora

RESUMEN

The pathogenesis of Parkinson's disease (PD) involves abnormalities in the metabolism of catecholamines. The enzyme quinone reductase 2 (NQO2) reduces quinone derivatives of catecholamines, which promotes the formation of reactive oxygen species (ROS), suggesting a role for NQO2 in the development of cellular damage typical of PD. In the present study, we investigated the relationship between 6-hydroxydophamine (6-OHDA) induced cellular damage and NQO2 activity and its levels in SH-SY5Y cell culture to establish an experimental model to evaluate the pharmacological properties of NQO2 inhibitors. Cellular damage was evaluated using the MTT and comet assays. It was shown that oxidative damage of SH-SY5Y cells upon incubation with 6-OHDA for 6, 12 and 24 h was accompanied by an increase in NQO2 activity. The increase in NQO2 protein level in SH-SY5Y cells was observed 24 h after incubation with 6-OHDA at concentrations of 50 and 100 µM. Oxidative damage of SH-SY5Y cells upon 1 h incubation with 6-OHDA is increased in the presence of the selective enzyme co-substrate 1-benzyl-1,4-dihydronicotinamide (BNAH), but is not accompanied by changes in NQO2 activity and protein levels. The data obtained demonstrate the contribution of NQO2 to the cytotoxic mechanism of 6-OHDA action.

RESUMEN

Parkinson's disease (PD) is a chronic neurodegenerative case. As the disease progresses, the response time to doses of levodopa (L-Dopa) becomes shorter and the effects of the drug are severely limited by some undesirable side effects such as the 'on-off' phenomenon. In several diseases, including Parkinson's, nanoparticles can deliver antioxidant compounds that reduce oxidative stress. This study evaluates and compares the neuroprotective effects of L-Dopa-modified zinc nanoparticles (ZnNPs) in the 6-hydroxydopamine (6-OHDA)-induced PD rat model. For this purpose, the synthesis of NPs was carried out. Scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectrophotometer were used for characterization. The rats were randomized into 9 experimental groups: control, lesion group (6-OHDA), 6-OHDA + 5 mg/kg L-Dopa, 6-OHDA + 10 mg/kg L-Dopa, 6-OHDA + 20 mg/kg L-Dopa, 6-OHDA + 20 mg/kg ZnNPs, 6-OHDA + 40 mg/kg ZnNPs, 6-OHDA + 30 mg/kg ZnNPs + L-Dopa, and 6-OHDA + 60 mg/kg ZnNPs + L-Dopa. Behavioral tests were performed on all groups 14 days after treatment. Phosphatase and tensin homolog, Excitatory amino acid transporter 1/2, and Glutamine synthetase gene analyses were performed on brain samples taken immediately after the tests. In addition, histological and immunohistochemical methods were used to determine the general structure and properties of the tissues. We obtained important findings that L-Dopa-modified ZnNPs increased the activity of glutamate transporters. Our experiment showed that glutamate increases neuronal cell vitality and improves behavioral performance. Therefore, L-Dopa-modified ZnNPs can be used to prevent neurotoxicity. According to what we found, results show that L-Dopa-modified ZnNPs will lend to the effective avoidance and therapy of PD.

Asunto(s)

Modelos Animales de Enfermedad , Levodopa , Fármacos Neuroprotectores , Oxidopamina , Óxido de Zinc , Animales , Levodopa/farmacología , Ratas , Fármacos Neuroprotectores/farmacología , Óxido de Zinc/química , Óxido de Zinc/farmacología , Masculino , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Nanopartículas del Metal/química , Nanopartículas/química , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/tratamiento farmacológico , Enfermedad de Parkinson Secundaria/patología , Enfermedad de Parkinson Secundaria/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar

RESUMEN

Aim: This study is primarily designed to investigate the potential neuroprotective effects of polyphenol against 6-OHDAcaused neurotoxicity on SH-SY5Y cells. Materials and Methods: Cytotoxic effect of 6-OHDA and valuable role of quercetin, myricetin and kaempferol on SH-SY5Y cells were analyzed by MTT assay. Generation of 6-OHDA-stimulated reactive oxygen species (ROS) was measured using DCFDA fluorescence dye. Alteration of 6-OHDA-caused mitochondrial membrane potential and nuclear condensation was investigated with the help of rhodamine-123 and hoechest stain. Immunoblotting was performed to detect the expression level of 6-OHDA-caused alpha-synuclein (á-syn), Bcl-2 associated protein X (BAX), caspase 3, cleaved Poly ADP - ribose polymerase (PARP) and Bcell lymphoma 2 proteins (Bcl-2). Result: Through MTT assay, quercetin was selected over myricetin and kaempferol to counter 6-OHDA-caused cell death. The research delves into unraveling the intricate mechanisms underlying 6-OHDA-induced neurotoxicity, encompassing alterations in cellular morphology, escalation of oxidative stress, perturbation in mitochondrial membrane potential, and nuclear condensation. Exposure to 6-OHDA is implicated in the upregulation of á-syn protein, contributing to the aggravation of neurotoxicity. Concurrently, 6-OHDA orchestrates the apoptotic pathway by upregulating the expression of proapoptotic proteins such as BAX, caspase 3, and PARP, while down regulating the expression of the Bcl-2, affirming its role in apoptosis induction. Quercetin demonstrated ability to attenuate the expression of á-syn in the presence of 6-OHDA-caused injury in SH-SY5Y cells. Conclusion: Taken together, these findings collectively underscore the therapeutic potential of quercetin as a promising agent against neurotoxicity caused by 6-OHDA.

RESUMEN

Background: Parkinson's disease (PD) is typified by inflammation of dopaminergic neurons leading to the release of various inflammatory mediators. These mediators activate the transcription factor NF-κB, which in turn activates inducible nitric oxide synthase (iNOS), leading to increased inflammation. Purpose: This study was intended to study the effect of combination of mangiferin, a specific inhibitor of NF-κB with low-dose nitric oxide (NO) modulators. Methods: A total of eight Wistar rats weighing 200-250 g were used in each group. Stereotactic surgery was performed to induce 6-hydroxydopamine (6-OHDA) lesions. The treatment period extended from day 14 to day 42, during which time behavioral tests were performed to evaluate the effects of mangiferin and its combination with NO modulators. On day 42, the brains of the rats were removed for biochemical and molecular analyzes. Results: Mangiferin significantly improved locomotor activity and decreased inflammatory chemokines levels in rats with 6-OHDA lesions. Mangiferin therapy decreased myeloperoxidase (MPO) levels and reduced oxidative stress. In particular, caspase-3, caspase-9 and COX-2 activities were significantly reduced after the mangiferin treatment. A combination of 45-µg mangiferin and 10-mg/kg L-NAME showed the greatest improvement in locomotor, behavioral, biochemical, and molecular parameters impaired by 6-OHDA. Conclusion: In this study, mangiferin was found to protect rats with 6-OHDA lesions by inhibiting inflammation causing chemokines such as TNF-α and IL-6. Besides, the grouping of iNOS inhibitor L-NAME at a dose of 10 mg/kg with 45-µg mangiferin enhanced the anti-inflammatory and anti-Parkinsonian activity of mangiferin. Consequently, the combination therapy of mangiferin and L-NAME is promising for the treatment of PD. However, clinical trials will be required to evaluate the efficacy of this combination therapy in humans.

RESUMEN

Depression and anxiety are prevalent neuropsychiatric conditions among patients with Parkinson's disease (PD), which may manifest prior to motor symptoms. As levodopa, a prominent treatment for PD motor symptoms, provides few benefits for mood-related abnormalities, tackling non-motor symptoms is particularly important. AdipoRon (Ad), an adiponectin agonist, has demonstrated neuroprotective effects by suppressing neuroinflammatory responses and activating the AMPK/Sirt-1 signaling pathway. This study looked at the potential advantages and underlying mechanisms of intranasal Ad in a rat model of PD induced by 6-hydroxydopamine (6-OHDA). We found that Ad at doses of 1 and 10 µg for 21 days exhibited anxiolytic- and antidepressant effects in the open field (OF) test, elevated plus maze (EPM), sucrose splash test, and forced swimming test in a PD model caused by a unilateral 6-OHDA injection into the medial forebrain bundle (MFB). The Ad also lowered the levels of corticosterone in the blood, decreased inflammasome components (NLRP3, caspase 1, and IL-1ß), and increased Sirt-1 protein levels in the prefrontal cortex (PFC) of PD rats. We conclude that Ad ameliorates anxious and depressive-like behaviors in the PD rat model through stimulating the AMPK/Sirt-1 signaling and blocking the NLRP3 inflammasome pathways in the PFC.

RESUMEN

Dopamine replacement therapy (DRT) of Parkinson's disease (PD) may trigger non-motor complications, some of which affect hedonic homeostatic regulation. Management of iatrogenic alterations in the affective state in PD is unsatisfactory, partly because of the limitations in the experimental models that are used in the preclinical investigation of the neurobiology and therapy of these alterations. In this connection, we recently employed a new experimental approach consisting in measuring the emission of 50-kHz ultrasonic vocalizations (USVs), a marker of positive affect, in hemiparkinsonian rats treated with drugs used in the DRT of PD. To further strengthen our approach, we here evaluated how the acute and repeated (× 5, on alternate days) administration of apomorphine (2 mg/kg, i.p.) or L-3,4-dihydroxyphenilalanine (L-DOPA, 12 mg/kg, i.p.) modified the immunoreactivity for Zif-268, a marker of neuronal activation, in the nucleus accumbens (NAc), caudate-putamen (CPu) and medial prefrontal cortex (mPFC), which are brain regions that regulate emotional states and drugs' affective properties. Acute and repeated treatment with either apomorphine or L-DOPA stimulated the emission of 50-kHz USVs in hemiparkinsonian rats, and this effect was paired with increased Zif-268 immunoreactivity in the NAc and CPu, but not mPFC. These findings indicate that subcortical and cortical regions may differently regulate the emission of 50-kHz USVs in hemiparkinsonian rats treated with dopaminergic drugs used in the DRT of PD. Moreover, they provide further evidence that measuring 50-kHz USV emissions in hemiparkinsonian rats may be a relevant approach to investigate at the preclinical level the affective properties of antiparkinsonian drugs.

Asunto(s)

Antiparkinsonianos , Apomorfina , Levodopa , Vocalización Animal , Animales , Ratas , Vocalización Animal/efectos de los fármacos , Masculino , Antiparkinsonianos/farmacología , Apomorfina/farmacología , Levodopa/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/inducido químicamente , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Neuronas/efectos de los fármacos , Ratas Wistar , Afecto/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Oxidopamina/toxicidad , Agonistas de Dopamina/farmacología

RESUMEN

Dopamine-modified hyaluronic acid (DA-HA) has been initially developed as an efficient coating and adhesion material for industrial uses. However, the biological activity and safety of DA-HA in the brain have not been explored yet. Here, we report a series of evidence that DA-HA exhibits similar functionality as dopamine (DA), but with much lower toxicity arising from autoxidation. DA-HA shows very little autoxidation even after 48-h incubation. This is profoundly different from DA and its derivatives including l-DOPA, which all induce severe neuronal death after pre-autoxidation, indicating that autoxidation is the cause of neuronal death. Furthermore, in vivo injection of DA-HA induces significantly lower toxicity compared to 6-OHDA, a well-known oxidized and toxic form of DA, and alleviates the apomorphine-induced rotational behavior in the 6-OHDA animal model of Parkinson's disease. Our study proposes that DA-HA with DA-like functionalities and minimal toxicity has a great potential to treat DA-related disease.

RESUMEN

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by selective dopaminergic loss. Non dopaminergic neurotransmitters such as glutamate are also involved in PD progression. NMDA receptor/postsynaptic density protein 95 (PSD-95)/neuronal nitric oxide synthase (nNOS) activation is involved in neuronal excitability in PD. Here, we are focusing on the evaluating these post-synaptic protein levels in the 6-OHDA model of PD. Adult male C57BL/6 mice subjected to unilateral striatal injury with 6-OHDA were assessed at 1-, 2-, or 4-weeks post-lesion. Animals were subjected to an apomorphine-induced rotation test followed by the analysis of protein content, synaptic structure, and NOx production. All biochemical analysis was performed comparing the control versus lesioned sides of the same animal. 6-OHDA mice exhibited contralateral rotation activity, difficulties in coordinating movements, and changes in Iba-1 and glial fibrillary acidic protein (GFAP) expression during the whole period. At one week of survival, the mice showed a shift in NMDA composition, favoring the GluN2A subunit and increased PSD95 and nNOS expression and NOx formation. After two-weeks, a decrease in the total number of synapses was observed in the lesioned side. However, the number of excitatory synapses was increased with a higher content of GluN1 subunit and PSD95. After four weeks, NMDA receptor subunits restored to control levels. Interestingly, NOx formation in the serum increased. This study reveals, for the first time, the temporal course of behavioral deficits and glutamatergic synaptic plasticity through NMDAr subunit shift. Together, these data demonstrate that dopamine depletion leads to a fine adaptive response over time, which can be used for further studies of therapeutic management adjustments with the progression of PD.

RESUMEN

Parkinson's disease (PD) results from the degeneration of dopaminergic neurons in substantia nigra pars compacta (SNpc). Adenosine A2AR acting through the striato-pallidal pathway has emerged as a non-dopaminergic target in the therapy of PD. In the present work, the anti-parkinsonian potential of (4E)-4-(4-bromobenzylideneamino)-3-phenyl-2,3-dihydro-2-thioxo- thiazole-5-carbonitrile (BBPT) was explored. BBPT exhibited significant antioxidant activity in situ. In the MTT assay, the BBPT treatment showed insignificant toxicity to the primary midbrain neuronal (PMDN) cells. 6-OHDA induced PMDN cells, 3 h post-treated with BBPT showed 80-85 % survival of the cells and restoration of dopamine and TNF-α levels. The acute and sub-acute toxicity test for BBPT was performed with Sprague Dawley (SD) rats. In toxicity assay, any significant physical, hematological, or biochemical changes in the rats were not observed. To evaluate the effect of BBPT in vivo, a 6-OHDA-induced unilaterally lesioned SD rat model of PD was established. We observed that the BBPT treatment improved the behavioral symptoms in 6-OHDA-induced unilaterally lesioned rats. The proteins of 6-OHDA-induced BBPT-treated rats were isolated from the brain tissue to assess the antioxidant effect (GSH, catalase, SOD, lipid-peroxidation, nitrite), dopamine levels, and the restoration in the apoptosis and inflammation. Our results demonstrated that BBPT increased the anti-oxidant enzyme levels, restored the caspase-3/Bcl-2 levels to arrest apoptosis, and attenuated the TNF-α/IL-6 levels, thus restoring the neuronal damage in unilaterally lesioned 6-OHDA-induced SD rats. Precisely, the findings suggested that BBPT possessed significant anti-parkinsonian activity and has the potential to prevent dopaminergic neurodegeneration.

RESUMEN

Background: Parkinson's disease (PD) affects more than 6 million people worldwide. Along with motor impairments, patients and animal models exhibiting PD symptoms also experience cognitive impairment, fatigue, anxiety, and depression. Currently, there are no drugs available for PD that alter the progression of the disease. A body of evidence suggests that increased GABA levels contribute to the reduced expression of tyrosine hydroxylase (TH) and accompanying behavioral deficits. TH expression may be restored by blocking GABAA receptors. We hypothesized that golexanolone (GR3027), a well-tolerated GABAA receptor-modulating steroid antagonist (GAMSA), may improve Parkinson's symptoms in a rat model of PD. Objectives: The aims of this study were to assess whether golexanolone can ameliorate motor and non-motor symptoms in a rat model of PD and to identify some underlying mechanisms. Methods: We used the unilateral 6-OHDA rat model of PD. The golexanolone treatment started 4 weeks after surgery. Motor symptoms were assessed using Motorater and CatWalk tests. We also analyzed fatigue (using a treadmill test), anhedonia (via the sucrose preference test), anxiety (with an open field test), and short-term memory (using a Y maze). Glial activation and key proteins involved in PD pathogenesis were analyzed using immunohistochemistry and Western blot. Results: Rats with PD showed motor incoordination and impaired locomotor gait, increased fatigue, anxiety, depression, and impaired short-term memory. Golexanolone treatment led to improvements in motor incoordination, certain aspects of locomotor gait, fatigue, anxiety, depression, and short-term memory. Notably, golexanolone reduced the activation of microglia and astrocytes, mitigated TH loss at 5 weeks after surgery, and prevented the increase of α-synuclein levels at 10 weeks. Conclusions: Golexanolone may be useful in improving both motor and non-motor symptoms that adversely affect the quality of life in PD patients, such as anxiety, depression, fatigue, motor coordination, locomotor gait, and certain cognitive alterations.

RESUMEN

Parkinson's disease (PD) is a neurodegenerative disorder which affects dopaminergic neurons of the midbrain. Accumulation of α-synuclein or exposure to neurotoxins like 6-hydroxydopamine (6-OHDA) induces endoplasmic reticulum (ER) stress along with the unfolded protein response (UPR), which executes apoptosis via activation of PERK/CHOP or IRE1/JNK signaling. The present study aimed to determine which of these pathways is a major contributor to neurodegeneration in an 6-OHDA-induced in vitro model of PD. For this purpose, we have applied pharmacological PERK and JNK inhibitors (AMG44 and JNK V) in differentiated SH-SY5Y cells exposed to 6-OHDA. Inhibition of PERK and JNK significantly decreased genotoxicity and improved mitochondrial respiration, but only JNK inhibition significantly increased cell viability. Gene expression analysis revealed that the effect of JNK inhibition was dependent on a decrease in MAPK10 and XBP1 mRNA levels, whereas inhibition of either PERK or JNK significantly reduced the expression of DDIT3 mRNA. Western blot has shown that JNK inhibition strongly induced the XBP1s protein, and inhibition of each pathway attenuated the phosphorylation of eIF2α and JNK, as well as the expression of CHOP. Collectively, our data suggests that targeting the IRE1/JNK pathway of the UPR is a more effective option for PD treatment as it simultaneously affects more than one pro-apoptotic pathway.

Asunto(s)

Estrés del Retículo Endoplásmico , Endorribonucleasas , Oxidopamina , Proteínas Serina-Treonina Quinasas , Factor de Transcripción CHOP , Respuesta de Proteína Desplegada , eIF-2 Quinasa , Humanos , Apoptosis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , eIF-2 Quinasa/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Endorribonucleasas/metabolismo , Endorribonucleasas/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 10 Activada por Mitógenos/metabolismo , Proteína Quinasa 10 Activada por Mitógenos/genética , Oxidopamina/farmacología , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Transducción de Señal/efectos de los fármacos , Factor de Transcripción CHOP/metabolismo , Factor de Transcripción CHOP/genética , Respuesta de Proteína Desplegada/efectos de los fármacos , Proteína 1 de Unión a la X-Box/metabolismo , Proteína 1 de Unión a la X-Box/genética

RESUMEN

Astrocytes specifically synthesize and release endozepines, a family of regulatory peptides including octadecaneuropeptide (ODN). We have previously reported that ODN rescues neurons and astrocytes from 6-OHDA-induced oxidative stress and cell death. The purpose of this study was to examine the potential implication of miR-34b, miR-29a, and miR-21 in the protective activity of ODN on 6-OHDA-induced oxidative stress and cell death in cultured rat astrocytes. Flow cytometry analysis showed that 6-OHDA increased the number of early apoptotic and apoptotic dead cells while treatment with the subnanomolar dose of ODN significantly reduced the number of apoptotic cells induced by 6-OHDA. 6-OHDA-treated astrocytes exhibited the over-expression of miR-21 (+118%) associated with a knockdown of miR-34b (-61%) and miR-29a (-49%). Co-treatment of astrocytes with ODN blocked the 6-OHDA-stimulated production of ROS and NO and stimulation of Bax and caspase-3 gene transcription. Concomitantly, ODN down-regulated the expression of miR-34b and miR-29a and rescued the 6-OHDA-associated reduced expression of miR21, indicating that ODN regulates their expression during cell death. Transfection with miR-21-3p inhibitor prevented the effect of 6-OHDA against cell death. In conclusion, our study indicated that (i) the expression of miRNAs miR-34b, miR-29a, and miR-21 is modified in astrocytes under 6-OHDA injury and (ii) that ODN prevents this deregulation to induce its neuroprotective action. The present study identified miR-21 as an emerging candidate and as a promising pharmacological target that opens new neuroprotective therapeutic strategies in neurodegenerative diseases, especially in Parkinson's disease.

Asunto(s)

Apoptosis , Astrocitos , Supervivencia Celular , MicroARNs , Estrés Oxidativo , Oxidopamina , MicroARNs/genética , MicroARNs/metabolismo , Animales , Astrocitos/metabolismo , Astrocitos/efectos de los fármacos , Apoptosis/efectos de los fármacos , Apoptosis/genética , Estrés Oxidativo/efectos de los fármacos , Oxidopamina/farmacología , Ratas , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Inhibidor de la Unión a Diazepam/metabolismo , Inhibidor de la Unión a Diazepam/genética , Especies Reactivas de Oxígeno/metabolismo , Neuropéptidos/metabolismo , Neuropéptidos/genética , Fragmentos de Péptidos , Ratas Wistar

RESUMEN

Calcium dyshomeostasis, oxidative stress, autophagy and apoptosis are the pathogenesis of selective dopaminergic neuronal loss in Parkinson's disease (PD). Earlier, we reported that A2A R modulates IP3-dependent intracellular Ca2+ signalling via PKA. Moreover, A2A R antagonist has been reported to reduce oxidative stress and apoptosis in PD models, however intracellular Ca2+ ([Ca2+]i) dependent autophagy regulation in the 6-OHDA model of PD has not been explored. In the present study, we investigated the A2A R antagonists mediated neuroprotective effects in 6-OHDA-induced primary midbrain neuronal (PMN) cells and unilateral lesioned rat model of PD. 6-OHDA-induced oxidative stress (ROS and superoxide) and [Ca2+]i was measured using Fluo4AM, DCFDA and DHE dye respectively. Furthermore, autophagy was assessed by Western blot of p-m-TOR/mTOR, p-AMPK/AMPK, LC3I/II, Beclin and ß-actin. Apoptosis was measured by Annexin V-APC-PI detection and Western blot of Bcl2, Bax, caspase3 and ß-actin. Dopamine levels were measured by Dopamine ELISA kit and Western blot of tyrosine hydroxylase. Our results suggest that 6-OHDA-induced PMN cell death occurred due to the interruption of [Ca2+]i homeostasis, accompanied by activation of autophagy and apoptosis. A2A R antagonists prevented 6-OHDA-induced neuronal cell death by decreasing [Ca2+]i overload and oxidative stress. In addition, we found that A2A R antagonists upregulated mTOR phosphorylation and downregulated AMPK phosphorylation thereby reducing autophagy and apoptosis both in 6-OHDA induced PMN cells and 6-OHDA unilateral lesioned rat model. In conclusion, A2A R antagonists alleviated 6-OHDA toxicity by modulating [Ca2+]i signalling to inhibit autophagy mediated by the AMPK/mTOR pathway.

Asunto(s)

Autofagia , Calcio , Oxidopamina , Serina-Treonina Quinasas TOR , Animales , Masculino , Ratas , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia/efectos de los fármacos , Autofagia/fisiología , Calcio/metabolismo , Células Cultivadas , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Oxidopamina/toxicidad , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Serina-Treonina Quinasas TOR/metabolismo

RESUMEN

BACKGROUND: Parkinson's disease is a neurological disorder caused by the loss of dopaminergic neurons in the midbrain. Various mechanisms are involved in the incidence of the disease including oxidative stress. Several herbs and natural products may interfere with the oxidative-stress pathway due to their antioxidant effects. OBJECTIVE: Herein, we aimed to investigate the neuroprotective role of F. vaillantii extract on Parkinson's in vitro and in vivo model owing to the presence of the bioactive agents with antioxidant properties. METHODS: In vitro experments showed that 6-hydroxydopamine could induce toxicity in PC12 cells. The impact of F. vaillantii extract on cell viability was measured by using MTT assay. Nuclear morphological changes were qualitatively evaluated employing Hoechst staining. The antioxidant activity of the extract was determined by ROS and lipid peroxidation assays. Tyrosine hydroxylase protein expression was measured by western blotting in PC12 cells. For in vivo study, movement parameters were evaluated. RESULTS: The results indicated that 75 µΜ of 6-OHDA induced 50% toxicity in PC12 cells for 24 h. Following post-treatment with F. vaillantii extract (0.1 mg/ml) for 72 h, we observed that the extract effectively prevented cell toxicity induced by 6-OHDA and reduced the apoptotic cell population. Furthermore, the extract attenuated the ROS level, lipid peroxidation and increased protein expression of TH after 72 h of treatment. In addition, oral administration of 300 mg/kg of F. vaillantii extract for 14 days improved locomotor activity, catalepsy, bradykinesia, motor coordination and reduced the apomorphine-caused rotation in 6-OHDA- induced Parkinson's disease-like symptoms in male rats. CONCLUSION: The present study suggests a protective role for the extract of F. vaillantii against oxidative stress-induced cell damage in the PC12 cells exposed to neurotoxin 6-OHDA which was verified in in vivo model by reducing the motor defects induced by 6-OHDA. This extract could be a promising therapeutic agent for the prevention of PD progression.

Asunto(s)

Antioxidantes , Supervivencia Celular , Fármacos Neuroprotectores , Estrés Oxidativo , Oxidopamina , Extractos Vegetales , Animales , Células PC12 , Ratas , Extractos Vegetales/farmacología , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Peroxidación de Lípido/efectos de los fármacos , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Masculino , Tirosina 3-Monooxigenasa/metabolismo

RESUMEN

Cell death involving oxidative stress and mitochondrial dysfunction is a major cause of dopaminergic neuronal loss in the substantia nigra (SN) of Parkinson's disease patients. Ergothioneine (ET), a natural dietary compound, has been shown to have cytoprotective functions, but neuroprotective actions against PD have not been well established. 6-Hydroxydopamine (6-OHDA) is a widely used neurotoxin to simulate the degeneration of dopaminergic (DA) neurons in Parkinson's disease. In this study, we investigated the protective effect of ET on 6-OHDA treated iPSC-derived dopaminergic neurons (iDAs) and further confirmed the protective effects in 6-OHDA-treated human neuroblastoma SH-SY5Y cells. In 6-OHDA-treated cells, decreased mitochondrial membrane potential (ΔΨm), increased mitochondrial reactive oxygen species (mROS), reduced cellular ATP levels, and increased total protein carbonylation levels were observed. 6-OHDA treatment also significantly decreased tyrosine hydroxylase levels. These effects were significantly decreased when ET was present. Verapamil hydrochloride (VHCL), a non-specific inhibitor of the ET transporter OCTN1 abrogated ET's cytoprotective effects, indicative of an intracellular action. These results suggest that ET could be a potential therapeutic for Parkinson's disease.

RESUMEN

Parkinson's disease (PD) caused by SNCA gene triplication (3XSNCA) leads to early onset, rapid progression, and often dementia. Understanding the impact of 3XSNCA and its absence is crucial. This study investigates the differentiation of human induced pluripotent stem cell (hiPSC)-derived floor-plate progenitors into dopaminergic neurons. Three different genotypes were evaluated in this study: patient-derived hiPSCs with 3XSNCA, a gene-edited isogenic line with a frame-shift mutation on all SNCA alleles (SNCA 4KO), and a normal wild-type control. Our aim was to assess how the substantia nigra pars compacta (SNpc) microenvironment, damaged by 6-hydroxydopamine (6-OHDA), influences tyrosine hydroxylase-positive (Th+) neuron differentiation in these genetic variations. This study confirms successful in vitro differentiation into neuronal lineage in all cell lines. However, the SNCA 4KO line showed unusual LIM homeobox transcription factor 1 alpha (Lmx1a) extranuclear distribution. Crucially, both 3XSNCA and SNCA 4KO lines had reduced Th+ neuron expression, despite initial successful neuronal differentiation after two months post-transplantation. This indicates that while the SNpc environment supports early neuronal survival, SNCA gene alterations-either amplification or knock-out-negatively impact Th+ dopaminergic neuron maturation. These findings highlight SNCA's critical role in PD and underscore the value of hiPSC models in studying neurodegenerative diseases.

RESUMEN

Controlled nigrostriatal dopamine release supports effective limb use during locomotion coordination that becomes compromised after this pathway deteriorates in Parkinson's Disease (PD). How dopamine release relates to active ongoing behavior control remains unknown. Restoring proper release strategy appears important to successful PD treatment with transplanted dopamine-producing stem cells. This is suggested by apparently distinct behavioral support from tonic or phasic release and corresponding requirements of requisite afferent control exhibited by intact nigrostriatal neurons. Our laboratory previously demonstrated that transplanted dopaminergic cells can elicit skilled movement recovery known to depend on phasic dopamine release. However, efforts to measure this movement-related dopamine release yielded seemingly paradoxical, incongruent results. In response, here we explored whether those previous observations derived from rapid reuptake transport into either transplanted cells or residual, lesion-surviving terminals. We confirmed this using minimal reuptake blockade during intrastriatal microdialysis. After unilateral dopamine depletion, rats received transplants and were subjected to our swimming protocol. Among dopamine-depleted and transplanted rats, treatment supported restoration of limb movement symmetry. Interestingly, subsequent reuptake-restricted microdialysis confirmed distinct swimming-induced dopamine increases clearly occurred among these lesioned/transplanted subjects. Thus, phasic firing control appears to contribute to transplant-derived recovery in Parkinsonian animals.

Asunto(s)

Modelos Animales de Enfermedad , Dopamina , Microdiálisis , Animales , Dopamina/metabolismo , Masculino , Ratas , Mesencéfalo/metabolismo , Oxidopamina/farmacología , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/fisiología , Cuerpo Estriado/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/fisiopatología , Trastornos Parkinsonianos/metabolismo , Trastornos Parkinsonianos/fisiopatología , Extremidades , Sustancia Negra/metabolismo , Ratas Sprague-Dawley

RESUMEN

OBJECTIVE: To investigate the effects of cannabidiol (CBD) on emotional and cognitive symptoms in rats with intra-nigral 6-hydroxydopamine (6-OHDA) lesions. METHODS: Adult male Wistar rats received bilateral intranigral 6-OHDA infusions and were tested in a battery of behavioural paradigms to evaluate non-motor symptoms. The brains were obtained to evaluate the effects of CBD on hippocampal neurogenesis. RESULTS: 6-OHDA-lesioned rats exhibited memory impairments and despair-like behaviour in the novelty-suppressed feeding test and forced swim test, respectively. The animals also exhibited dopaminergic neuronal loss in the substantia nigra pars compacta (SNpc), striatum, and ventral tegmental area and a reduction of hippocampal neurogenesis. CBD decreased dopaminergic neuronal loss in the SNpc, reduced the mortality rate and decreased neuroinflammation in 6-OHDA-lesioned rats. In parallel, CBD prevented memory impairments and attenuated despair-like behaviour that were induced by bilateral intranigral 6-OHDA lesions. Repeated treatment with CBD favoured the neuronal maturation of newborn neurons in the hippocampus in Parkinsonian rats. CONCLUSION: The present findings suggest a potential beneficial effect of CBD on non-motor symptoms induced by intra-nigral 6-OHDA infusion in rats.