Potential new therapies against a toxic relationship: neuroinflammation and Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder classically associated with motor symptoms, but several nonmotor disturbances appear decades before the clinical diagnosis of the disease. A variety of hypotheses exist to explain the onset of PD, and neuroinflammation is one of the most investigated processes. In fact, strong evidence suggests that PD begins with an inflammatory process; currently, however, no anti-inflammatory therapy is clinically employed to alleviate the typical motor and the prodromal disturbances such as olfactory loss, cognitive impairments, depression and anxiety, sleep disturbances, and autonomic disorders. In fact, the classical dopaminergic therapies are not effective in alleviating these symptoms and there is no other specific therapy for these outcomes. Therefore, in this review, we will discuss novel potential pharmacological therapeutic strategies focusing on cannabinoids, caffeine, melatonin, and dietary compounds, which could act as adjuvants to regular PD therapy. These described chemicals have been extensively investigated as anti-inflammatory agents possibly promoting beneficial effects on nonmotor symptoms of PD. The investigation of the inflammatory process at different stages of PD progression should give us a better view of the therapeutic scenario and could improve our understanding of the mechanisms of this disease.

Immune system responses in Parkinson's disease: Early and dynamic.

The neuropathological hallmarks of Parkinson's disease (PD) are the degeneration and death of dopamine-producing neurons in the ventral midbrain, the widespread intraneuronal aggregation of alpha-synuclein (α) in Lewy bodies and neurites, neuroinflammation, and gliosis. Signs of microglia activation in the PD brain postmortem as well as during disease development revealed by neuroimaging, implicate immune responses in the pathophysiology of the disease. Intensive research during the last two decades has advanced our understanding of the role of these responses in the disease process, yet many questions remain unanswered. A transformative finding in the field has been the confirmation that in vivo microglia are able to respond directly to pathological a-syn aggregates but also to neuronal dysfunction due to intraneuronal a-syn toxicity well in advance of neuronal death. In addition, clinical research and disease models have revealed the involvement of both the innate and adaptive immune systems. Indeed, the data suggest that PD leads not only to a microglia response, but also to a cellular and humoral peripheral immune response. Together, these findings compel us to consider a more holistic view of the immunological processes associated with the disease. Central and peripheral immune responses aimed at maintaining neuronal health will ultimately have consequences on neuronal survival. We will review here the most significant findings that have contributed to the current understanding of the immune response in PD, which is proposed to occur early, involve peripheral and brain immune cells, evolve as neuronal dysfunction progresses, and is likely to influence disease progression.

Niacin modulates macrophage polarization in Parkinson's disease.

Neuroinflammation remains a central piece in Parkinson's disease (PD) pathophysiology. However, mechanisms by which PD links to the neuroinflammation remain elusive. Here, for the first time, we report that lower dose of niacin in PD patients may affect macrophage polarization from M1 (pro-inflammatory) to M2 (counter-inflammatory) profile through the niacin receptor GPR109A. Skew in the peripheral macrophages were accompanied by improved quality of life assessments in patients. Low dose niacin supplementation may be beneficial in PD, boosting anti-inflammatory processes and suppressing inflammation. Varied niacin dosages for longer durations may further reveal the potential role of anti-inflammatory interventions in PD progression.

Neuroprotective strategies to prevent and treat Parkinson's disease based on its pathophysiological mechanism.

Parkinson's disease (PD) is the second most common progressive neurodegenerative disease after Alzheimer's disease. PD exhibits clinical symptoms that include tremors, rigidity, and bradykinesia. Many drugs are available to treat PD, such as, L-dopa, COMT inhibitor, MAO-B inhibitor, and dopamine agonists, but these drugs simply compensate for dopamine loss in PD, and therefore, cannot completely suppress its symptoms or progression. Although the causes of PD are not clearly understood, common pathophysiological pathways, such as, oxidative stress, mitochondrial dysfunction, and neuroinflammation are considered to be etiological factors, and thus, many treatments and interventions have been developed to target these pathophysiological factors. This review describes the neuroprotective strategies devised based on current understanding of the pathophysiological mechanisms of PD.

The implication of neuronimmunoendocrine (NIE) modulatory network in the pathophysiologic process of Parkinson's disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder implicitly marked by the substantia nigra dopaminergic neuron degeneration and explicitly characterized by the motor and non-motor symptom complexes. Apart from the nigrostriatal dopamine depletion, the immune and endocrine study findings are also frequently reported, which, in fact, have helped to broaden the symptom spectrum and better explain the pathogenesis and progression of PD. Nevertheless, based on the neural, immune, and endocrine findings presented above, it is still difficult to fully recapitulate the pathophysiologic process of PD. Therefore, here, in this review, we have proposed the neuroimmunoendocrine (NIE) modulatory network in PD, aiming to achieve a more comprehensive interpretation of the pathogenesis and progression of this disease. As a matter of fact, in addition to the classical motor symptoms, NIE modulatory network can also underlie the non-motor symptoms such as gastrointestinal, neuropsychiatric, circadian rhythm, and sleep disorders in PD. Moreover, the dopamine (DA)-melatonin imbalance in the retino-diencephalic/mesencephalic-pineal axis also provides an alternative explanation for the motor complications in the process of DA replacement therapy. In conclusion, the NIE network can be expected to deepen our understanding and facilitate the multi-dimensional management and therapy of PD in future clinical practice.

Immunopathogenesis of neurodegenerative diseases: current therapeutic models of neuroprotection with special reference to natural products.

Parkinson disease (PD) and Alzheimer disease (AD) are neurodegenerative processes whose frequency is dramatically increasing in the western world. Both diseases share a common pathogenic denominator characterized by an exaggerated activation of the systemic and cerebral immune system, respectively. For instance, lipopolysaccharides in PD and amyloid beta in AD trigger microglia and astrocytes to release reactive oxygen species (ROS) and proinflammatory cytokines. Infiltrating peripheral T cells once activated in the central nervous system also contribute to the neurodegenerative process. Besides innovative biotherapy, nutraceuticals or functional foods are currently investigated for their neuroprotective activities. Especially, vitamin D and polyphenols, seem to be promising therapeutic tools for inhibiting ROS formation and arresting cytokine-mediated neuroinflammation in PD and AD.

[Mechanism of traditional Chinese medicine on animal model of Parkinson's disease].

Parkinson's disease (PD) is a common degenerative disease of the central nervous system, but no drug has been found to be surely able to protect neurons so far, delay onset or slow progression of the disease. Currently there are a variety of Chinese formulas, single herb medicines, active fractions and monomers showed prophylactic and therapeutic effect on PD animal models. The mechanisms include protection of substantia nigra cells, improvement of neurotransmitter content, anti-oxidation, immune regulation, enhancement of Western medicine efficacy, reduction of side effects, etc. All these mechanisms may play integrated effect and slow disease progression. In particular, Chinese medicine compound may have some advantages in neuroprotective treatment of PD, because a variety of active ingredients can exert multi-links, multi-levels and multi-targets integrated regulation effect on human body. However, the level and standard of Chinese medicine studies on PD animal still need to be improved.

The immunoregulatory role of dopamine: an update.

The neurotransmitter dopamine (DA) is an important molecule bridging the nervous and immune systems. DA through autocrine/paracrine manner modulates the functions of immune effector cells by acting through its receptors present in these cells. DA also has unique and opposite effects on T cell functions. Although DA activates naïve or resting T cells, but it inhibits activated T cells. In addition, changes in the expression of DA receptors and their signaling pathways especially in T cells are associated with altered immune functions in disorders like schizophrenia and Parkinson's disease. These results suggest an immunoregulatory role of DA. Therefore, targeting DA receptors and their signaling pathways in these cells by using DA receptor agonists and antagonists may be useful for the treatment of diseases where DA induced altered immunity play a pathogenic role.

Inflammation in Parkinson's disease: an update.

Parkinson's disease (PD) is a degenerative neurological disorder characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) of the brain. The loss of the dopaminergic projection from the SNpc deprives the striatum of dopamine and results in a myriad of motor signs, including tremor, rigidity and ataxia. Although the stimulus for the initiation of the degenerative process is not understood, 80% of the dopaminergic neurons in the SNpc must be lost before the clinical symptoms of the disease are observed. This suggests that the degenerative process is initiated many years before clinical presentation of the disease. The neurodegeneration observed in PD is accompanied by inflammatory processes, and it has been suggested that anti-inflammatory drugs may be useful in slowing disease progression once the clinical signs of PD have been observed. This review summarizes and evaluates the progress that has been made in this area of research since 2006.

[Biochemical and immunological induces of the blood in Parkinson's disease and their correction with the help of laser therapy]. / Biokhimicheskie i immunologicheskie pokazateli krovi pri bolezni Parkinsona i vozmozhnosti ikh korrektsii s pomoshch''iu lazernoi terapii.

The influence of laser therapy on the course of Parkinson's disease (PD) was studied in 70 patients. This influence appeared adaptogenic both in the group with elevated and low MAO B and Cu/Zn SOD activity. Laser therapy resulted in reduction of neurological deficit, normalization of the activity of MAO B, Cu/Zn-SOD and immune indices. There was a correlation between humoral immunity and activity of the antioxidant enzymes (SOD, catalase). This justifies pathogenetically the use of laser therapy in PD.

The hypothalamus in Parkinson disease.

It is currently believed that Parkinson disease (PD) is due to a degenerative process that independently damages multiple areas of the central and peripheral nervous system. Loss of nigrostriatal dopamine is now widely recognized as being directly related to the motor symptoms in Parkinson's disease. Parkinsonian patients also exhibit symptoms and signs suggestive of hypothalamic dysfunction (e.g. dysautonomia, impaired heat tolerance). The latter clinical features are supported by pathological, biochemical and endocrinological findings. Lewy body formation has been demonstrated in every nucleus of the hypothalamus, specifically the tuberomamillary and posterior hypothalamic. Preferential involvement of the hypothalamus was also noted in patients after post-encephalitic parkinsonism. Loss of dopamine (30-40%) in the hypothalamus of affected patients has been shown in recent studies, and is compatible with the reported abnormalities of growth hormone release in response to L-dopa administration, elevated plasma levels of MSH, and reduced CSF levels of somatostatin and beta-endorphins in these patients. Deranged immunological mechanisms have been found in PD patients including the presence of autoantibodies against sympathetic ganglia neurons, adrenal medulla and caudate nucleus. On the evidence of on pathological studies demonstrating the early vulnerability of the hypothalamus in aging and PD, and the known role of the hypothalamus in immune modulation, we expect that it will be shown that primary damage of the hypothalamus leads to subsequent secondary degeneration of structures receiving direct projections from the hypothalamus. Within this framework, the dopaminergic systems may be damaged, since striatal dopamine synthesis and receptor sensitivity have been shown to be regulated by ACTH and alpha-MSH through direct arcuate nucleus-striatal projections.(ABSTRACT TRUNCATED AT 250 WORDS)