Association of Parkinson Disease Induction with Cardiac Upregulation of Apoptotic Mediators P53 and Active Caspase-3: An Immunohistochemistry Study

Total Glucosides of White Paeony Capsule ameliorates Parkinson's disease-like behavior in MPTP-induced mice model by regulating LRRK2/alpha-synuclein signaling

ETHNOPHARMACOLOGICAL RELEVANCE

The Total Glucosides of White Paeony Capsule (TGPC), one of the traditional Chinese patent medicines, has been used for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) in clinical practice. Besides, the components of TGPC are extracted from Radix Paeoniae Alba (RPA) and have displayed neuroprotective properties.

AIM OF THE STUDY

The present study was designed to evaluate the anti-PD-like effects of TGPC on a 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mice model and explore its potential molecular mechanisms.

MATERIALS AND METHODS

Behavioral tests, hematoxylin and eosin (HE) staining, Nissl staining, immunohistochemistry (IHC), western blotting (WB) and Enzyme-Linked Immunosorbent Assay (ELISA) were performed in this study.

RESULTS

It was observed that TGPC treatment (150, 300 mg/kg) significantly reversed MPTPinduced PD-like behaviors, such as reduced locomotive activity in the open field test, prolonged time to turn downward on the ball (T-turn) and to climb down the whole pole (T-descend) in the pole test, decreased movement scores in the traction test and extended the latency to fall in the hanging wire test. In addition, TGPC improved neurodegeneration, inhibited the excessive activation of microglia and suppressed the overproduction of proinflammatory cytokines induced by MPTP, partially by restoring leucine-rich repeat kinase 2 (LRRK2) activity and inhibiting alpha-synuclein (α-syn) mediated neuroinflammation signaling.

CONCLUSION

Taken together, TGPC exhibited neuroprotective effects on MPTP-induced mice model of PD, which was associated with the prevention of neuroinflammation and neurodegeneration modulated by LRRK2/α-syn pathway.

Autophagy and Its Association with Genetic Mutations in Parkinson Disease

Parkinson disease is the second most common neurodegenerative disorder, affecting 0.1-0.2% of the general population. It is a progressive debilitating disorder caused by degeneration of dopaminergic neurons in the substantia nigra pars compacta. It is characterized by motor and non-motor symptoms. Parkinson disease can be caused by mutations in genes that encode proteins involved in the autophagic process, resulting in impaired autophagy. Indeed, autophagy has been implicated in the pathogenesis of Parkinson disease, particularly because its impairment causes the buildup of proteins. Thus, this review aims to provide an overview of Parkinson disease-related genetic mutations and their association with autophagy impairment in Parkinson disease, which can be helpful in improving the understanding of the pathogenesis of Parkinson disease, illustrating the potential therapeutic implications of agents that can enhance autophagy in Parkinson disease. Additionally, we will highlight the essential need for the development of highly sensitive and specific assays for gene-based diagnostic biomarkers. Finally, we will provide an overview on the potential gene-based therapeutic approaches for Parkinson disease, which have been most advanced and are associated with the most common targets being alpha-synuclein (SNCA), leucine-rich repeat kinase-2 (LRRK2), and glucocerebrosidase (GBA).

Association of p53 with Neurodegeneration in Parkinson's Disease

p53 is a vital transcriptional protein implicated in regulating diverse cellular processes, including cell cycle arrest, DNA repair, mitochondrial metabolism, redox homeostasis, autophagy, senescence, and apoptosis. Recent studies have revealed that p53 levels and activity are substantially increased in affected neurons in cellular and animal models of Parkinson's disease (PD) as well as in the brains of PD patients. p53 activation in response to neurodegenerative stress is closely associated with the degeneration of dopaminergic neurons accompanied by mitochondrial dysfunction, reactive oxygen species (ROS) production, abnormal protein aggregation, and impairment of autophagy, and these pathogenic events have been implicated in the pathogenesis of PD. Pathogenic p53 integrates diverse cellular stresses and activate these downstream events to induce the degeneration of dopaminergic neurons; thus, it plays a crucial role in the pathogenesis of PD and appears to be a potential target for the treatment of the disease. We reviewed the current knowledge concerning p53-dependent neurodegeneration to better understand the underlying mechanisms and provide possible strategies for PD treatment by targeting p53.

Endurance exercise training suppresses myostatin upregulation and nuclear factor-kappa B activation in a mouse model of Parkinson's disease

Background and Aim:

Muscle atrophy is common in Parkinson’s disease (PD). Although myostatin has been implicated in muscle atrophy, its expression in PD skeletal muscle has not been investigated. Therefore, this study aimed to elucidate the influence of PD induction and exercise training on myostatin expression in the gastrocnemius skeletal muscle.

Materials and Methods:

Thirty albino mice were randomly selected and separated into three groups of 10 mice each: Sedentary control, sedentary PD (SPD), and exercised PD (EPD). 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine and probenecid were used to induce chronic parkinsonism in the PD groups. Immunohistochemistry was used to investigate the expression of myostatin and nuclear factor kappa B (NF-kB) in gastrocnemius muscles of all three groups.

Results:

Myostatin expression and NF-kB nuclear localization, indicative of its activation, were significantly (p<0.01) higher in gastrocnemius skeletal muscle in the SPD group than in the control and EPD groups. Concomitantly, the average cross-sectional area of gastrocnemius muscle fibers in the SPD albino mice was significantly smaller (p<0.01) than in the control and EPD groups, indicating muscle atrophy.

Conclusion:

The present data are the first to indicate a correlation between PD induction and myostatin overexpression and NF-kB activation in the gastrocnemius muscle, potentially promoting the muscle atrophy commonly seen in PD. Additionally, the current data are the first to indicate the beneficial effects of exercise training on PD-associated myostatin overexpression, NF-κB activation, and muscle atrophy. Thus, our data are the first to suggest that myostatin and NF-κB might be regarded as potential therapeutic targets in an attempt to ameliorate skeletal muscle abnormalities commonly observed in PD.

Autophagy and apoptosis cascade: which is more prominent in neuronal death?

Autophagy and apoptosis are two crucial self-destructive processes that maintain cellular homeostasis, which are characterized by their morphology and regulated through signal transduction mechanisms. These pathways determine the fate of cellular organelle and protein involved in human health and disease such as neurodegeneration, cancer, and cardiovascular disease. Cell death pathways share common molecular mechanisms, such as mitochondrial dysfunction, oxidative stress, calcium ion concentration, reactive oxygen species, and endoplasmic reticulum stress. Some key signaling molecules such as p53 and VEGF mediated angiogenic pathway exhibit cellular and molecular responses resulting in the triggering of apoptotic and autophagic pathways. Herein, based on previous studies, we describe the intricate relation between cell death pathways through their common genes and the role of various stress-causing agents. Further, extensive research on autophagy and apoptotic machinery excavates the implementation of selective biomarkers, for instance, mTOR, Bcl-2, BH3 family members, caspases, AMPK, PI3K/Akt/GSK3β, and p38/JNK/MAPK, in the pathogenesis and progression of neurodegenerative diseases. This molecular phenomenon will lead to the discovery of possible therapeutic biomolecules as a pharmacological intervention that are involved in the modulation of apoptosis and autophagy pathways. Moreover, we describe the potential role of micro-RNAs, long non-coding RNAs, and biomolecules as therapeutic agents that regulate cell death machinery to treat neurodegenerative diseases. Mounting evidence demonstrated that under stress conditions, such as calcium efflux, endoplasmic reticulum stress, the ubiquitin-proteasome system, and oxidative stress intermediate molecules, namely p53 and VEGF, activate and cause cell death. Further, activation of p53 and VEGF cause alteration in gene expression and dysregulated signaling pathways through the involvement of signaling molecules, namely mTOR, Bcl-2, BH3, AMPK, MAPK, JNK, and PI3K/Akt, and caspases. Alteration in gene expression and signaling cascades cause neurotoxicity and misfolded protein aggregates, which are characteristics features of neurodegenerative diseases. Excessive neurotoxicity and misfolded protein aggregates lead to neuronal cell death by activating death pathways like autophagy and apoptosis. However, autophagy has a dual role in the apoptosis pathways, i.e., activation and inhibition of the apoptosis signaling. Further, micro-RNAs and LncRNAs act as pharmacological regulators of autophagy and apoptosis cascade, whereas, natural compounds and chemical compounds act as pharmacological inhibitors that rescue neuronal cell death through inhibition of apoptosis and autophagic cell death.

Common Inflammatory Mechanisms in COVID-19 and Parkinson's Diseases: The Role of Microbiome, Pharmabiotics and Postbiotics in Their Prevention

In the last decade, metagenomic studies have shown the key role of the gut microbiome in maintaining immune and neuroendocrine systems. Malfunction of the gut microbiome can induce inflammatory processes, oxidative stress, and cytokine storm. Dysfunction of the gut microbiome can be caused by short-term (virus infection and other infectious diseases) or long-term (environment, nutrition, and stress) factors. Here, we reviewed the inflammation and oxidative stress in neurodegenerative diseases and coronavirus infection (COVID-19). Here, we reviewed the renin-angiotensin-aldosterone system (RAAS) involved in the processes of formation of oxidative stress and inflammation in viral and neurodegenerative diseases. Moreover, the coronavirus uses ACE2 receptors of the RAAS to penetrate human cells. The coronavirus infection can be the trigger for neurodegenerative diseases by dysfunction of the RAAS. Pharmabiotics, postbiotics, and next-generation probiotics, are considered as a means to prevent oxidative stress, inflammatory processes, neurodegenerative and viral diseases through gut microbiome regulation.

Endurance exercise training suppresses Parkinson disease-induced overexpression of apoptotic mediators in the heart

BACKGROUNDWe have shown elevated levels of p53 and active caspase-3 in the heart with Parkinson disease (PD). The main aim of this study is to examine the effect of treadmill training on the cardiac expression of p53 and active caspase-3 in the mouse with induced Parkinsonism.

METHODS

Thirty randomly selected normal albino mice were equally divided into the following 3 groups: sedentary control (SC), sedentary Parkinson diseased (SPD), and exercised Parkinson diseased (EPD). 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and probenecid (MPTP/p) were used to induce chronic Parkinson disease in the SPD and EPD animals. The expression of p53 and active caspase-3 was investigated, using immunohistochemistry, in the heart in each animal group.

RESULTS

Both p53 and active caspase-3 expression was significantly (p value < 0.05) reduced in the PD heart following endurance exercise training.

CONCLUSION

Our present data suggest that chronic exercise training reduced PD-induced upregulation of p53 and active caspase-3 in the heart. Thus, our study suggests that inhibiting p53 and/or active caspase-3 may be considered as a therapeutic approach to ameliorate PD cardiomyopathy.

COVID-19 and Parkinson's Disease: Shared Inflammatory Pathways Under Oxidative Stress

The current coronavirus pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in a serious global health crisis. It is a major concern for individuals living with chronic disorders such as Parkinson’s disease (PD). Increasing evidence suggests an involvement of oxidative stress and contribution of NFκB in the development of both COVID-19 and PD. Although, it is early to identify if SARS-CoV-2 led infection enhances PD complications, it is likely that oxidative stress may exacerbate PD progression in COVID-19 affected individuals and/or vice versa. In the current study, we sought to investigate whether NFκB-associated inflammatory pathways following oxidative stress in SARS-CoV-2 and PD patients are correlated. Toward this goal, we have integrated bioinformatics analysis obtained from Basic Local Alignment Search Tool of Protein Database (BLASTP) search for similarities of SARS-CoV-2 proteins against human proteome, literature review, and laboratory data obtained in a human cell model of PD. A Parkinson’s like state was created in 6-hydroxydopamine (6OHDA)-induced differentiated dopamine-containing neurons (dDCNs) obtained from an immortalized human neural progenitor cell line derived from the ventral mesencephalon region of the brain (ReNVM). The results indicated that SARS-CoV-2 infection and 6OHDA-induced toxicity triggered stimulation of caspases-2, -3 and -8 via the NFκB pathway resulting in the death of dDCNs. Furthermore, specific inhibitors for NFκB and studied caspases reduced the death of stressed dDCNs. The findings suggest that knowledge of the selective inhibition of caspases and NFκB activation may contribute to the development of potential therapeutic approaches for the treatment of COVID-19 and PD.

Cardiac Noradrenaline Turnover and Heat Shock Protein 27 Phosphorylation in Dyskinetic Monkeys

BACKGROUND

Autonomic dysfunction is a well-known dominant symptom in the advanced stages of Parkinson's disease. However, the role of cardiac sympathetic nerves still needs to be elucidated.

OBJECTIVES

To evaluate cardiac sympathetic response in Parkinsonian and dyskinetic monkeys.

METHODS

Adult male monkeys were divided into 1 of the following 3 groups: controls, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated monkeys, and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine+levodopa-treated animals. Noradrenaline, its metabolite normetanephrine, and phospho-Heat shock proten 27 (p-Hsp27) at serine 82 levels were analyzed in the left and right ventricles of the heart. Tyrosine hydroxylase immunohistochemistry was performed in the ventral mesencephalon.

RESULTS

The results were the following: (1) 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxication significantly increased normetanephrine levels and decreased noradrenaline turnover in the right ventricle without changes in the left ventricle; however, (2) levodopa treatment decreased noradrenaline levels and enhanced the normetanephrine/noradrenaline ratio in parallel with a very significant increase of Hsp27 activity in both ventricles.

CONCLUSIONS

Levodopa treatment could induce protective cardiac effects through the increased Hsp27 activity. © 2019 International Parkinson and Movement Disorder Society.

The Protective Effect of Korean Red Ginseng Against Rotenone-Induced Parkinson's Disease in Rat Model: Modulation of Nuclear Factor-κβ and Caspase-3

OBJECTIVE

Korean red ginseng was reported to have many biological effects like the antioxidant and the anti-inflammatory activities. Oxidative stress and neuro-inflammation play major roles in the pathogenesis of Parkinson's disease (PD). The current study aimed to investigate the protective effects of ginseng on rotenone-induced PD in rats.

METHODS

Rats were randomly allocated into 4 groups: normal rats, rotenone control, ginseng+rotenone and ginseng only treated rats. The severity of PD was evaluated through locomotor activity perceived in the open field test, histological examination and immunohistochemical detection of amyloid-β in brain tissues, in addition to the biochemical assessment of tyrosine hydroxylase activity in brain tissues. Moreover, the following parameters were investigated for studying the possible mechanisms of ginseng neuroprotective effect: nuclear factor-κβ (NF-κβ), tumor necrosis factor-alpha (TNF-α), caspase- 3, lipid peroxides and reduced glutathione (GSH).

RESULTS

Ginseng exhibited potent neuroprotective effect that was reflected upon the histopathological examination, marked improvement in the locomotor activity and through its ability to suppress the amyloid- β deposition in the cortex and striatum along with significant increase in the tyrosine hydroxylase activity. Ginseng successfully inhibited the NF-κβ inflammatory pathway in brain tissues beside the inhibition of other oxidative stress and inflammatory mediators. Furthermore, it exhibited antiapoptotic effect via the inhibition of caspase-3 expression.

CONCLUSION

Ginseng could be a promising treatment in PD. It can suppress dopaminergic neuron degeneration through variable mechanisms mainly via inhibition of NF-κβ pathway in addition to inhibition of oxidative stress and apoptosis.

Cerebellar Upregulation of Cell Surface Death Receptor-Mediated Apoptotic Factors in Harmaline-Induced Tremor: An Immunohistochemistry Study

Active caspase-3-mediated apoptosis has been implicated in the pathogenesis of harmaline-induced tremor. The aim of this study is to illustrate the impact of tremor induction on the expression of factors mediating the cell surface death receptor–dependent apoptosis. A total of 20 normal Wistar rats were randomly selected and equally divided into control and experimental groups. Tremor was induced in the experimental group by injecting the rats with a single dose of harmaline (50 mg/kg). After that, cerebellar tissues were evaluated by immunohistochemistry to examine the expression of tumor necrosis factor α (TNF-α) and active caspase-8 in the 2 groups of animals. TNF-α and active caspase-8 expression was significantly higher in cerebella from experimental rats compared with that in those from the control rats (P value < .01). Thus, our present data suggest the association of tremor induction with the cerebellar overexpression of TNF-α and active caspase-8, correlative with Purkinje cell (PC) loss indicated by loss of calbindin immunoreactivity, indicating the induction of the cell surface death receptor–mediated apoptosis.