[Preserve brain function...through physical exercice?]

Over the last few years, there has been an increasing interest in the relationship between brain function and physical exercise. Preliminary evidence from observational and interventional studies in humans suggests a positive and robust effect of chronic aerobic exercise on several brain functions across the entire lifespan. Physical activity and exercise might also serve to reduce the risk of age-associated neurological disorders such as Alzheimer's and Parkinson's diseases. The mechanisms underlying these beneficial effects remain poorly understood. More scientific work is needed before disseminating more specific recommendations to the general population.

Multiple molecular pathways are involved in the neuroprotection of GDNF against proteasome inhibitor induced dopamine neuron degeneration in vivo

The impairment of ubiquitin-proteasome system (UPS) is a cellular mechanism underlying the neurodegenerative process in Parkinson's disease (PD). Glial cell line-derived neurotrophic factor (GDNF) is one of the most potent neurotrophic factors promoting the growth and survival of mesencephalic dopamine (DA) neurons. To investigate whether GDNF has neuroprotective effects in a PD model induced by UPS impairment we administered GDNF by osmotic pump in C57BL/6 mice after nigrostriatal lesions with stereotactic injection of proteasome inhibitor lactacystin in the middle forebrain bundle. We found that lactacystin injection severely injured the nigral DA neurons and reduced the striatal levels of DA and its metabolites, while prolonged administration of GDNF at a sustained moderate dose for two weeks can significantly attenuate the lactacystin-induced loss of nigral DA neurons and striatal DA levels by 31% and 40%, respectively. We also investigated the molecular mechanisms for the neuroprotective effects of GDNF showing that lactacystin administration can cause the phosphorylation of extracellular signal-regulated kinase (ERK), p38MAPK (p38), and the c-Jun N-terminal kinase (JNK), whereas GDNF treatment can further enhance the phosphorylation of ERK and Akt but reduce the levels of JNK and p38. These results indicate that prolonged treatment with GDNF can protect the nigral DA neurons from the UPS impairment-induced degeneration. Several signaling path-ways including p38, JNK, Akt and ERK molecules seem to play an important role in this neuroprotection by GDNF.

Protection against Parkinson's disease progression: clinical experience

Treatments with potential neuroprotective capability for Parkinson's disease (PD) have been investigated in randomized, controlled, clinical trials and other studies since the mid-1980s. Although promising leads have arisen, no therapy has been proven to halt or slow disease progression. Several large-scale studies have highlighted progress in methodology, as well as the frustrations of translating laboratory science to practical applications. This review summarizes findings from clinical trials with several classes of compounds, including monoamine oxidase-B inhibitors (selegiline, lazabemide, rasagiline), dopaminergic drugs (ropinirole, pramipexole, levodopa), antioxidant strategies (alpha-tocopherol), mitochondrial energy enhancers (coenzyme Q(10), creatine), antiapoptotic agents (TCH346, minocycline, CEP-1347), and antiglutamatergic compounds (riluzole). Beyond small-molecule pharmacology, gene therapy approaches, such as delivering neurotrophic substances (e.g., neurturin) by viral vector, are the next generation of treatment options.

[Isolation and identification of Suavissimoside R1 from roots of Rubus parvifollus used for protecting dopaminergic neurons against MPP+ toxicity]

OBJECTIVE

Suavissimoside R1 was isolated and identified as an active ingredient from Roots of Rubus parvifollus L, which exhibited protective effect on dopaminergic neurons against MPP+ toxicity.

METHODS

The protective effects of crude extracts were investigated after mice were treated with 1-methyl4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). According to the protective effects of crude extracts, suavissimoside R1, one kind of triterpenoid saponin, was separated. It was investigated that whether Suavissimoside R1 can protect DA neurons from toxicity induced by MPP+ in rat mesencephalic cultures.

RESULTS

Suavissimoside R1 was isolated from Roots of Rubus parvifollus L. Moreover, Suavissimoside R1, in dose of 100 micromol/L, alleviated the death of DA neurons induced by MPP+ obviously.

CONCLUSION

These results suggest that suavissimoside R1 possesses potent neuroprotective activity and can be developed to be a potential anti-Parkinson's disease drug worthy for further study.

Differential effects of black versus green tea on risk of Parkinson's disease in the Singapore Chinese Health Study

Data from Asian populations on dietary and lifestyle factors associated with Parkinson's disease are sparse. In 1993-2005, the authors examined these factors in relation to Parkinson's disease in the Singapore Chinese Health Study, a prospective cohort of 63,257 Chinese men and women. Baseline data were collected through in-person interviews using structured questionnaires. All 157 incident Parkinson's disease cases were identified either through follow-up interviews or via linkage with hospital discharge databases and Parkinson's disease outpatient registries and were confirmed by review of medical records. Current versus never smokers exhibited a reduced risk of Parkinson's disease (relative risk = 0.29, 95% confidence interval: 0.16, 0.52). Total caffeine intake was inversely related to Parkinson's disease risk (p for trend = 0.002); the relative risk for the highest versus lowest quartile was 0.55 (95% confidence interval: 0.35, 0.88). Black tea, a caffeine-containing beverage, showed an inverse association with Parkinson's disease risk that was not confounded by total caffeine intake or tobacco smoking (p for trend = 0.0006; adjusted relative risk for the highest vs. lowest tertile of intake = 0.29, 95% confidence interval: 0.13, 0.67). Green tea drinking was unrelated to Parkinson's disease risk. Diet had no strong influence on risk. Ingredients of black tea other than caffeine appear to be responsible for the beverage's inverse association with Parkinson's disease.

Alzheimer's disease and other neurological disorders

Menopausal status and estrogen-containing hormone therapy may influence several neurological disorders, including Alzheimer's disease, epilepsy, migraine headache, multiple sclerosis, Parkinson's disease, sleep disorders, and stroke. For most of these illnesses, evidence on hormone therapy is insufficient to guide practice decisions. For stroke, clinical trial evidence indicates that hormone therapy increases risk of cerebral infarction. For women with Alzheimer's disease, estrogen treatment trials have tended to be small and of short duration. Most suggest that estrogen started after the onset of dementia symptoms does not meaningfully improve cognition or slow disease progression. Hormone therapy initiated after age 64 increased all-cause dementia in the Women's Health Initiative Memory Study. Many observational studies, however, report protective associations between hormone use and Alzheimer risk. Apparent risk reduction may represent a bias toward hormone therapy, since hormones are more often prescribed to healthier women. However, when compared to the Women's Health Initiative Memory Study, estrogen exposures in many observational studies reflect hormone initiation at a younger age, closer to the time of menopause. One intriguing hypothesis is that hormone therapy initiated or used during an early critical window may reduce later Alzheimer incidence. Public health implications of this hypothesis are important, but current data are inadequate to decide the issue.

Protective effects of green tea polyphenols in the 6-OHDA rat model of Parkinson's disease through inhibition of ROS-NO pathway

BACKGROUND

Nitric oxide (NO) and related pathways are thought to play an important role in the pathogenesis of Parkinson's disease (PD). Our in vitro experiments suggested that green tea polyphenols (GTP) might protect dopamine neurons through inhibition of NO and reactive oxygen species (ROS).

METHODS

Immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP Nick End Labeling assay, electron spin resonance spin trapping, enzyme linked immunosorbent assay, and molecular biological methods were used to investigate the effects of GTP in an unilateral 6-hydroxydopamine (6-OHDA)-treated rat model of PD.

RESULTS

GTP treatment dose-dependently protected dopaminergic neurons by preventing from midbrain and striatal 6-OHDA-induced increase in 1) both ROS and NO levels, 2) lipid peroxidation, 3) nitrite/nitrate content, 4) inducible nitric oxide synthase, and 5) protein-bound 3-nitro-tyrosine. Moreover, GTP treatment dose-dependently preserved the free radical scavenging capability of both the midbrain and the striatum.

CONCLUSIONS

These results support the in vivo protection of GTP against 6-OHDA and suggest that GTP treatment might represent a neuroprotective treatment of PD.

Short-term supplementation with plant extracts rich in flavonoids protect nigrostriatal dopaminergic neurons in a rat model of Parkinson's disease

OBJECTIVE

Antioxidants from plants were known to reduce the oxidative stress by scavenging free radicals, chelating metal ions and reducing inflammation. As increased oxidative stress was implicated in the nigrostriatal dopaminergic neuronal loss in Parkinson's disease (PD), we have assessed whether the plant extracts protects the nigrostriatal dopaminergic neurons in the animal model of PD.

METHODS

Male adult Sprague-Dawley rats were treated orally between 10 am-11 am each day with the extracts from tangerine peel, grape seeds, cocoa and red clover for four days. One hour after the final dosing, the left medial forebrain bundle was lesioned by infusing the dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA; 12 microg) under anaesthesia. Seven days post-lesion, the number of dopaminergic cells in the substantia nigra pars compacta and the levels of dopamine and its metabolites 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the striata were quantified and compared with the vehicle-treated groups.

RESULTS

Compared to the unlesioned side, 6-OHDA lesions significantly reduced the number of dopaminergic cells and the levels of dopamine and its metabolites DOPAC and HVA in the vehicle-treated animals. Pretreatment of animals with extracts of tangerine peel (rich in polymethoxylated flavones; 35 mg/kg/day), cocoa-2 (rich in procyanidins; 100 mg/kg/day) and red clover (rich in isoflavones; 200 mg/kg/day) significantly attenuated the 6-OHDA-induced dopaminergic loss. However, no significant protection was seen in animals supplemented with red and white grape seeds (rich in catechins; 100 mg/kg/day), and cocoa-1 (rich in catechins; 100 mg/kg/day).

CONCLUSIONS

Pre-treatment of plant extracts rich in polymethoxylated flavones, procyanidins and isoflavones but not catechins protected the nigrostriatal dopaminergic neurons in the rat model of PD.

Calcium, ageing, and neuronal vulnerability in Parkinson's disease

Parkinson's disease is a common neurodegenerative disorder of unknown cause. There is no cure or proven strategy for slowing the progression of the disease. Although there are signs of pathology in many brain regions, the core symptoms of Parkinson's disease are attributable to the selective degeneration of dopaminergic neurons in the substantia nigra pars compacta. A potential clue to the vulnerability of these neurons is their increasing reliance on Ca(2+) channels to maintain autonomous activity with age. This reliance could pose a sustained metabolic stress on mitochondria, accelerating cellular ageing and death. The Ca(2+) channels underlying autonomous activity in dopaminergic neurons are closely related to the L-type channels found in the heart and smooth muscle. Systemic administration of isradipine, a dihydropyridine blocker of L-type channels, forces dopaminergic neurons in rodents to revert to a juvenile, Ca(2+)-independent mechanism to generate autonomous activity. More importantly, reversion confers protection against toxins that produce experimental parkinsonism, pointing to a potential neuroprotective strategy for Parkinson's disease with a drug class that has been used safely in human beings for decades. These studies also suggest that, although genetic and environmental factors can hasten its onset, Parkinson's disease stems from a distinctive neuronal design common to all human beings, making its appearance simply a matter of time.

Protection of dopaminergic neurons by electroconvulsive shock in an animal model of Parkinson’s disease

Electroconvulsive shock (ECS) improves motor function in Parkinson's disease. In rats, ECS stimulates the expression of various factors some of which have been proposed to exert neuroprotective actions. We have investigated the effects of ECS on 6-hydroxydopamine (6-OHDA)-injected rats. Three weeks after a unilateral administration of 6-OHDA, 85-95% nigral dopaminergic neurons are lost. Chronic ECS prevented this cell loss, protect the nigrostriatal pathway (assessed by FloroGold retrograde labeling) and reduce motor impairment in 6-OHDA-treated animals. Injection of 6-OHDA caused loss of expression of glial cell-line derived neurotrophic factor (GDNF) in the substantia nigra. Chronic ECS completely prevented this loss of GDNF expression in 6-OHDA-treated animals. We also found that protected dopaminergic neurons co-express GDNF receptor proteins. These results strongly suggest that endogenous changes in GDNF expression may participate in the neuroprotective mechanism of ECS against 6-OHDA induced toxicity.

Vitamin E and neurodegenerative diseases

Vitamin E is essential for neurological function. This fact, together with a growing body of evidence indicating that neurodegenerative processes are associated with oxidative stress, lead to the convincing idea that several neurological disorders may be prevented and/or cured by the antioxidant properties of vitamin E. In this review, some aspects related to the role of vitamin E against Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and ataxia with vitamin E deficiency will be presented.

Angiotensin II protects against alpha-synuclein toxicity and reduces protein aggregation in vitro

In this study, we examined the effects of angiotensin II (AngII) in a genetic in vitro PD model produced by alpha-synuclein (alpha-syn) overexpression in the human neuroglioma H4 cell line. We observed a maximal decrease in alpha-syn-induced toxicity of 85% and reduction in inclusion formation by 19% when cultures were treated with AngII in the presence of the angiotensin type 1 (AT1) receptor antagonist losartan and AT2 receptor antagonist PD123319. When compared to AngII, the AT4 receptor agonist AngIV was moderately effective in protecting H4 cells against alpha-syn toxicity and did not significantly reduce inclusion formation. Here we show that AngII is protective against genetic, as well as neurotoxic models of PD. These data support the view that agents acting on the renin-angiotensin-system (RAS) may be useful in the prevention and/or treatment of Parkinson's disease.

Nonsteroidal anti-inflammatory drugs and the risk of Parkinson disease

BACKGROUND

Several lines of evidence suggest a role of inflammatory processes in Parkinson disease, although it is still unclear whether inflammation is a cause or rather a consequence of neurodegeneration.

METHODS

In a prospective population-based cohort study among 6,512 participants aged >or=55 years, with repeated in-person examination, we evaluated the association between cumulative use of nonsteroidal anti-inflammatory drugs (NSAIDs) and the risk of Parkinson disease. Complete information on filled prescriptions was available from automated pharmacy records. Data were analyzed by means of Cox proportional hazards regression analysis, adjusted for age, sex, smoking habits and coffee consumption.

RESULTS

After an average 9.4 years of follow-up, 88 new cases of Parkinson disease were detected. No association was found between use of NSAIDs and the risk of Parkinson disease (adjusted hazard ratio for any NSAID use, 1.50; 95% confidence interval, 0.95-2.37).

CONCLUSION

Our findings do not support the hypothesis that NSAIDs might decrease the risk of Parkinson disease.

Simvastatin is associated with a reduced incidence of dementia and Parkinson's disease

BACKGROUND

Statins are a class of medications that reduce cholesterol by inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A reductase. Whether statins can benefit patients with dementia remains unclear because of conflicting results. We hypothesized that some of the confusion in the literature might arise from differences in efficacy of different statins. We used a large database to compare the action of several different statins to investigate whether some statins might be differentially associated with a reduction in the incidence of dementia and Parkinson's disease.

METHODS

We analyzed data from the decision support system of the US Veterans Affairs database, which contains diagnostic, medication and demographic information on 4.5 million subjects. The association of lovastatin, simvastatin and atorvastatin with dementia was examined with Cox proportional hazard models for subjects taking statins compared with subjects taking cardiovascular medications other than statins, after adjusting for covariates associated with dementia or Parkinson's disease.

RESULTS

We observed that simvastatin is associated with a significant reduction in the incidence of dementia in subjects > or =65 years, using any of three models. The first model incorporated adjustment for age, the second model included adjusted for three known risk factors for dementia, hypertension, cardiovascular disease or diabetes, and the third model incorporated adjustment for the Charlson index, which is an index that provides a broad assessment of chronic disease. Data were obtained for over 700,000 subjects taking simvastatin and over 50,000 subjects taking atorvastatin who were aged >64 years. Using model 3, the hazard ratio for incident dementia for simvastatin and atorvastatin are 0.46 (CI 0.44-0.48, p < 0.0001) and 0.91 (CI 0.80-1.02, p = 0.11), respectively. Lovastatin was not associated with a reduction in the incidence of dementia. Simvastatin also exhibited a reduced hazard ratio for newly acquired Parkinson's disease (HR 0.51, CI 0.4-0.55, p < 0.0001).

CONCLUSION

Simvastatin is associated with a strong reduction in the incidence of dementia and Parkinson's disease, whereas atorvastatin is associated with a modest reduction in incident dementia and Parkinson's disease, which shows only a trend towards significance.

Neuroprotective effect of nicotine on dopaminergic neurons by anti-inflammatory action

Epidemiological studies have reported that smoking is associated with a lower incidence of Parkinson's disease (PD), leading to theories that smoking in general and nicotine in particular might be neuroprotective. Recent studies suggested cholinergic anti-inflammatory pathway-regulating microglial activation through alpha7 nicotinic receptors. In the present study, we used lipopolysaccharide (LPS)-induced in vitro and in vivo inflammation models to investigate whether nicotine has a protective effect on the dopaminergic system through an anti-inflammatory mechanism. Nicotine pretreatment considerably decreased microglial activation with significant reduction of tumour necrosis factor (TNF)-alpha mRNA expression and TNF-alpha release induced by LPS stimulation. In co-cultures of microglia and mesencephalic neurons, nicotine pretreatment significantly decreased the loss of tyrosine hydroxylase-immunopositive (TH-ip) cells, approximately twice more than the LPS-only treatment. alpha-Bungarotoxin, an alpha7 nicotinic acetylcholine receptor subunit-selective blocker, considerably blocked the inhibitory effects of nicotine on microglial activation and TH-ip neuronal loss. Chronic nicotine pretreatment in rats showed that TH-ip neuronal loss induced by LPS stimulation in the substantia nigra was dramatically decreased, which was clearly accompanied by a reduction in the formation of TNF-alpha. The present study demonstrated that nicotine has a neuroprotective effect on dopaminergic neurons via an anti-inflammatory mechanism mediated by the modulation of microglial activation. Along with various neuroprotective effects of nicotine, the anti-inflammatory mechanism of nicotine could have a major therapeutic implication in the preventive treatment of PD.

Antioxidative and anti-inflammatory effects of four cysteine-containing agents in striatum of MPTP-treated mice

OBJECTIVES

Mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used to examine the neuroprotective effects of n-acetyl cysteine (NAC), s-ethyl cysteine (SEC), s-methyl cysteine (SMC), and s-propyl cysteine (SPC).

METHODS

Each agent at 1 g/L was directly added to the drinking water for 3 wk. Mice were treated by subcutaneous injection of MPTP (24 mg/kg body weight) for 6 consecutive days. The brain from each mouse was quickly removed and the striatum was collected for analyses.

RESULTS

The MPTP treatment significantly depleted striatal glutathione content, reduced the activity of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase, increased malondialdehyde level, and elevated interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) levels in striatum (P < 0.05). The pre-intake of NAC, SEC, SMC, and SPC significantly attenuated MPTP-induced glutathione loss, retained the activity of GPX and SOD, diminished oxidative stress, and suppressed MPTP-induced elevation of IL-6 and TNF-alpha (P < 0.05). MPTP treatment significantly suppressed GPX mRNA expression and enhanced TNF-alpha mRNA expression (P < 0.05). Compared with MPTP treatment alone, the pre-intake of NAC, SEC, SMC, and SPC significantly elevated GPX mRNA expression and diminished TNF-alpha mRNA expression (P < 0.05), in which SPC showed the greatest suppressive effect against MPTP-induced TNF-alpha mRNA expression (P < 0.05). Dopamine and 3,4-dihydroxyphenylacetic acid contents in the striatum were significantly decreased by MPTP treatment (P < 0.05). The pre-intake of four test agents significantly improved MPTP-induced dopamine depletion and increased dopamine/3,4-dihydroxyphenylacetic acid content (P < 0.05).

CONCLUSION

These results suggest that these cysteine-containing compounds could provide antioxidative and anti-inflammatory protection for the striatum against the development of Parkinson's disease.

Is Parkinson's disease an autoimmune disorder of endogenous vasoactive neuropeptides?

Parkinson's disease (PD) is a motor disease including disorders of mobility, fine tremor, rigidity and posture caused by a relentless deterioration of dopaminergic cells in the substantia nigra (SN). Disorders of affect and a range of other symptoms including fatigue, cognitive dysfunction and mental confusion, sleep disorder and addictions are also seen as other CNS sites are also affected. Idiopathic and genetic causes together with inflammatory and degenerative disorders of ageing have been postulated as contributing to PD. Autoimmunity affecting certain vasoactive neuropeptides (VNs) has been postulated as contributing to certain fatigue-related conditions in humans and may be consistent with compromise of receptors associated with VNs and including receptors for vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP). Pro-inflammatory responses are seen in PD patients consistent with apoptotic neurodegeneration. Involvement of the Th1 directed cytokine interferon-gamma has been demonstrated and Th2 directed cytokines such as IL-10 protect against inflammation-mediated degeneration of dopaminergic neurons in the SN. Nitric-oxide dysregulation is also postulated in PD by fostering dopamine depletion via nitric-oxide synthase (iNOS). Both PACAP and VIP have neuroprotective effects in PD models by inhibiting the production of inflammatory mediators. PACAP specifically protects against the neurotoxicity induced by rotenone as well as protecting against oxidative stress-induced apoptosis. These findings suggest that a defect in VN function may act adversely on SN cells and hence contribute to a clinical presentation consistent with PD. The conclusion drawn from these findings is that PD may be an autoimmune disorder of VNs, specifically PACAP and VIP. Possibly unusual or anatomically specific receptors for these VNs may be involved. If proven, this hypothesis would have significant implications for immunological and pharmacological treatment and prevention of PD.

‘Rejuvenation’ protects neurons in mouse models of Parkinson’s disease

Why dopamine-containing neurons of the brain's substantia nigra pars compacta die in Parkinson's disease has been an enduring mystery. Our studies suggest that the unusual reliance of these neurons on L-type Ca(v)1.3 Ca2+ channels to drive their maintained, rhythmic pacemaking renders them vulnerable to stressors thought to contribute to disease progression. The reliance on these channels increases with age, as juvenile dopamine-containing neurons in the substantia nigra pars compacta use pacemaking mechanisms common to neurons not affected in Parkinson's disease. These mechanisms remain latent in adulthood, and blocking Ca(v)1.3 Ca2+ channels in adult neurons induces a reversion to the juvenile form of pacemaking. Such blocking ('rejuvenation') protects these neurons in both in vitro and in vivo models of Parkinson's disease, pointing to a new strategy that could slow or stop the progression of the disease.

An orally active catalytic metalloporphyrin protects against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxicity in vivo

Parkinson's disease (PD) is an age-related neurodegenerative disease in which the role of reactive oxygen species (ROS) is strongly implicated. The presence of oxidative stress has been detected in human and experimental PD using both direct and indirect indices. Scavenging ROS is, therefore, an important therapeutic avenue for the treatment of PD. Manganic porphyrins are catalytic antioxidants that scavenge a wide range of ROS. In this study, we tested the therapeutic effects of a compound [5,15-bis(methoxycarbonyl)-10,20-bis-trifluoromethyl-porphyrinato manganese (III) chloride (AEOL11207)] belonging to a new generation of lipophilic manganic porphyrins for neuroprotection and oral bioavailability in the mouse 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of parkinsonism. Groups of adult C57BL/6 mice were administered MPTP with varying subcutaneous or oral dosing regimens of AEOL11207. Neurotoxicity was assessed by measurement of striatal dopamine levels and quantification of tyrosine hydroxylase-positive neurons in the substantial nigra pars compacta one week after the first dose of MPTP. Glutathione depletion, lipid peroxidation, and 3-nitrotyrosine (3-NT) formation were measured as indicators of oxidative stress in the ventral midbrain in vivo. AEOL11207 administered either by subcutaneous or oral routes protected against MPTP-induced dopamine depletion in the striatum as well as dopaminergic neuronal loss, glutathione depletion, lipid peroxidation, and 3-NT formation in the ventral midbrain. Neuroprotection correlated with brain metalloporphyrin concentrations. This is the first demonstration of neuroprotection by an orally active catalytic antioxidant in the MPTP mouse model and suggests its potential clinical utility for the treatment of chronic neurodegenerative diseases such as PD.

Pathological gambling in Parkinson's disease

Patients often are in substantial debt before the problem is recognised

Nicotine neuroprotection against nigrostriatal damage: importance of the animal model

Parkinson's disease is a neurodegenerative movement disorder that is characterized by a loss of nigrostriatal dopamine-containing neurons. Unexpectedly, there is a reduced incidence of Parkinson's disease in tobacco users. This finding is important because the identification of the component(s) responsible for this effect could lead to therapeutic strategies to slow down or halt the progression of Parkinson's disease. Results from cell culture models consistently show that nicotine protects against neurotoxicity. However, data from animal models of nigrostriatal damage are conflicting, thus raising questions about a neuroprotective role of nicotine. Accumulating evidence indicates that discrepancies are observed primarily in mouse models of the disease. By contrast, reproducible protection occurs in rat models and in a nonhuman primate parkinsonian model that closely resembles the human disease. These findings highlight the need to use the appropriate animal model and treatment conditions when testing putative neuroprotective agents.

Mitochondrial complex I inhibition in Parkinson's disease: how can curcumin protect mitochondria?

Selective damage of mitochondrial complex I within the dopaminergic neurons of the substantia nigra is the central event during Parkinson disease. Peroxynitrite is one of the important free radicals probably mediating complex I damage. Peroxynitrite inhibits brain complex I mainly by 3-nitrotyrosine and nitrosothiol formation, but how these modifications alter the structure-function relation of complex I is unclear. Curcumin pretreatment protects brain mitochondria against peroxynitrite in vitro by direct detoxification and prevention of 3-nitrotyrosine formation and in vivo by elevation of total cellular glutathione levels. These results suggest a potential therapeutic role for curcumin against nitrosative stress in neurological disorders.

Patient education in Parkinson's disease: Formative evaluation of a standardized programme in seven European countries

OBJECTIVE

To evaluate a newly developed education programme for Parkinson's disease (PD) patients.

METHODS

The programme consisted of eight sessions and aimed at improving knowledge and skills related to self-monitoring, health promotion, stress management, depression, anxiety, social competence, and social support, all with special reference to PD. The programme was formatively evaluated in seven European countries (Spain, Finland, Italy, The Netherlands, United Kingdom, Estonia, Germany) with 151 patients diagnosed with idiopathic PD. The evaluation included patients' ratings of the comprehensibility and feasibility of the programme as well as mood ratings before and after each session. Patients also completed questionnaires at the beginning and end of the programme to explore possible changes in disease-related psychosocial problems, quality of life, and depression.

RESULTS

The programme was feasible to run, and patients were able to understand its elements. Patients reported mood elevations following individual sessions and reduced disease-related psychosocial problems after completing the programme. There were no substantial differences in results between cultures.

CONCLUSION

Patient education appears to have potential as a useful and feasible intervention, complementing medical treatment in PD.

PRACTICE IMPLICATIONS

The present programme will soon be available in seven European languages and can be tested in different health care systems.