Association of circulating TNF-alpha and IL-6 with ageing and parkinsonism

An in-depth understanding of the role and mechanisms of T cells in immune organ aging and age-related diseases

T cells play a critical and irreplaceable role in maintaining overall health. However, their functions undergo alterations as individuals age. It is of utmost importance to comprehend the specific characteristics of T-cell aging, as this knowledge is crucial for gaining deeper insights into the pathogenesis of aging-related diseases and developing effective therapeutic strategies. In this review, we have thoroughly examined the existing studies on the characteristics of immune organ aging. Furthermore, we elucidated the changes and potential mechanisms that occur in T cells during the aging process. Additionally, we have discussed the latest research advancements pertaining to T-cell aging-related diseases. These findings provide a fresh perspective for the study of T cells in the context of aging.

A pilot randomized clinical trial examining the effects of Qigong on inflammatory status and sleep quality in people with Parkinson's disease

BACKGROUND

Neuroinflammation contributes to degeneration of neurons in people with Parkinson's disease (PD). The concentrations of inflammatory cytokines, IL-1β, IL-6, and TNF-α, are often increased in people with PD and are associated with various non-motor symptoms. Qigong exercise is a mind-body practice which has been used as a rehabilitation intervention for people with PD. A previous study showed a strong association between sleep quality and inflammatory status. This study investigated the effect of Qigong on inflammatory status in people with PD and explored potential relationships between inflammatory status and sleep quality in this population.

METHODS

The study was a randomized controlled trial. A total of 17 participants completed the 12-week intervention (Qigong (n = 8), sham Qigong (n = 9)). Questionnaires were utilized to assess non-motor symptoms, including sleep quality. Inflammatory cytokines were measured by a high sensitivity antibody-based multiplex assay.

RESULTS

After the 12-week intervention, a decreasing trend in the concentrations of IL-1β and IL-6 was found in the Qigong group. Moderate to strong correlations were found between changes in IL-1β concentrations and sleep quality.

CONCLUSION

Inflammation is an important aspect of PD. This study explored the inflammatory status after a mind-body exercise. Further studies need to extend our findings to confirm the effect of Qigong in people with PD.

The regulation of NFKB1 on CD200R1 expression and their potential roles in Parkinson's disease

BACKGROUND

Overactivated microglia are a key contributor to Parkinson's disease (PD) by inducing neuroinflammation. CD200R1, a membrane glycoprotein mainly found on microglia, is crucial for maintaining quiescence with its dysregulation linked to microglia's abnormal activation. We and other groups have reported a decline in CD200R1 levels in several neurological disorders including PD. However, the mechanism regulating CD200R1 expression and the specific reasons for its reduction in PD remain largely unexplored. Given the pivotal role of transcription factors in gene expression, this study aimed to elucidate the transcriptional regulation of CD200R1 and its implications in PD.

METHODS

The CD200R1 promoter core region was identified via luciferase assays. Potential transcription factors were predicted using the UCSC ChIP-seq database and JASPAR. NFKB1 binding to the CD200R1 core promoter was substantiated through electrophoretic mobility shift and chromatin immunoprecipitation assays. Knocking-down or overexpressing NFKB1 validated its regulatory effect on CD200R1. Correlation between decreased CD200R1 and deficient NFKB1 was studied using Genotype-Tissue Expression database. The clinical samples of the peripheral blood mononuclear cells were acquired from 44 PD patients (mean age 64.13 ± 9.78, 43.2% male, median Hoehn-Yahr stage 1.77) and 45 controls (mean age 64.70 ± 9.41, 52.1% male). NFKB1 knockout mice were utilized to study the impact of NFKB1 on CD200R1 expression and to assess their roles in PD pathophysiology.

RESULTS

The study identified the CD200R1 core promoter region, located 482 to 146 bp upstream of its translation initiation site, was directly regulated by NFKB1. Significant correlation between NFKB1 and CD200R1 expression was observed in human PMBCs. Both NFKB1 and CD200R1 were significantly decreased in PD patient samples. Furthermore, NFKB1-/- mice exhibited exacerbated microglia activation and dopaminergic neuron loss after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment.

CONCLUSION

Our study identified that NFKB1 served as a direct regulator of CD200R1. Reduced NFKB1 played a critical role in CD200R1 dysregulation and subsequent microglia overactivation in PD. These findings provide evidence that targeting the NFKB1-CD200R1 axis would be a novel therapeutic strategy for PD.

Targeting Microglia in Neuroinflammation: H3 Receptor Antagonists as a Novel Therapeutic Approach for Alzheimer's Disease, Parkinson's Disease, and Autism Spectrum Disorder

Histamine performs dual roles as an immune regulator and a neurotransmitter in the mammalian brain. The histaminergic system plays a vital role in the regulation of wakefulness, cognition, neuroinflammation, and neurogenesis that are substantially disrupted in various neurodegenerative and neurodevelopmental disorders. Histamine H3 receptor (H3R) antagonists and inverse agonists potentiate the endogenous release of brain histamine and have been shown to enhance cognitive abilities in animal models of several brain disorders. Microglial activation and subsequent neuroinflammation are implicated in impacting embryonic and adult neurogenesis, contributing to the development of Alzheimer's disease (AD), Parkinson's disease (PD), and autism spectrum disorder (ASD). Acknowledging the importance of microglia in both neuroinflammation and neurodevelopment, as well as their regulation by histamine, offers an intriguing therapeutic target for these disorders. The inhibition of brain H3Rs has been found to facilitate a shift from a proinflammatory M1 state to an anti-inflammatory M2 state, leading to a reduction in the activity of microglial cells. Also, pharmacological studies have demonstrated that H3R antagonists showed positive effects by reducing the proinflammatory biomarkers, suggesting their potential role in simultaneously modulating crucial brain neurotransmissions and signaling cascades such as the PI3K/AKT/GSK-3β pathway. In this review, we highlight the potential therapeutic role of the H3R antagonists in addressing the pathology and cognitive decline in brain disorders, e.g., AD, PD, and ASD, with an inflammatory component.

Safety and efficacy of nivolumab in elderly patients with metastatic clear cell renal cell carcinoma: Analysis of the NIVOREN GETUG-AFU 26 study

INTRODUCTION

Immune checkpoint inhibitors are standard of care in metastatic renal cell carcinoma but their activity and safety in elderly patients is insufficiently explored. We evaluated outcomes of elderly patients with mRCC treated with nivolumab in the GETUG-AFU 26 NIVOREN phase 2 trial (NCT03013335) and conducted exploratory circulating biomarker analyses.

METHODS

Patients with mRCC were treated with nivolumab after at least one antiangiogenic therapy. The main endpoint of this analysis was safety in patients ≥ 70 years old (y.o), as per the rate of treatment-related grade 3-5 events (TRAE). Secondary endpoints included overall response rate (ORR), progression-free survival (PFS), overall survival. Exploration of candidate biomarkers associated with aging included baseline circulating cytokines involved in inflammation, adhesion, immune checkpoints, angiogenesis (IL6, IL7, IL8, BAFF, CXCL13, VCAM-1, 4-1BB, VEGF).

RESULTS

Of 720 patients, 515 were < 70 y.o and 205 ≥ 70 y.o. Patients ≥ 70 y.o exhibited numerically less IMDC poor risk disease (21.0% vs 26.9%), sarcomatoid component (4.9% vs 9.8%) or brain metastases (5.9% vs. 14.7%), but more previous treatment lines (≥ 2 in 54.1% vs 48.5%). TRAE were higher in patients ≥ 70 y.o (24.9% vs. 17.9%, p = 0.033). Respective ORR (19.2% vs. 22.1%) and median PFS (4.5 versus 3.0 months, HR 0.97 [95%CI 0.81-1.15]) were similar. Overall survival was shorter in patients ≥ 70 y.o (19.3 versus 26.9 months, HR 1.26 [95%CI 1.04-1.51]), but not significantly in a competitive risk model. Only V-CAM1 and 4-1BB were found to be increased in patients ≥ 70 y.o.

CONCLUSIONS

Nivolumab displayed higher grade 3/4 TRAE but manageable toxicity in elderly patients, with sustained activity. Elderly patients did not display specific inflammatory or angiogenic circulating profiles.

Gardenin A treatment attenuates inflammatory markers, synuclein pathology and deficits in tyrosine hydroxylase expression and improves cognitive and motor function in A53T-α-syn mice

Oxidative stress and neuroinflammation are widespread in the Parkinson's disease (PD) brain and contribute to the synaptic degradation and dopaminergic cell loss that result in cognitive impairment and motor dysfunction. The polymethoxyflavone Gardenin A (GA) has been shown to activate the NRF2-regulated antioxidant pathway and inhibit the NFkB-dependent pro-inflammatory pathway in a Drosophila model of PD. Here, we evaluate the effects of GA on A53T alpha-synuclein overexpressing (A53TSyn) mice. A53TSyn mice were treated orally for 4 weeks with 0, 25, or 100 mg/kg GA. In the fourth week, mice underwent behavioral testing and tissue was harvested for immunohistochemical analysis of tyrosine hydroxylase (TH) and phosphorylated alpha synuclein (pSyn) expression, and quantification of synaptic, antioxidant and inflammatory gene expression. Results were compared to vehicle-treated C57BL6J mice. Treatment with 100 mg/kg GA improved associative memory and decreased abnormalities in mobility and gait in A53TSyn mice. GA treatment also reduced pSyn levels in both the cortex and hippocampus and attenuated the reduction in TH expression in the striatum seen in A53Tsyn mice. Additionally, GA increased cortical expression of NRF2-regulated antioxidant genes and decreased expression of NFkB-dependent pro-inflammatory genes. GA was readily detectable in the brains of treated mice and modulated the lipid profile in the deep gray brain tissue of those animals. While the beneficial effects of GA on cognitive deficits, motor dysfunction and PD pathology are promising, future studies are needed to further fully elucidate the mechanism of action of GA, optimizing dosing and confirm these effects in other PD models.

Intensity-effects of strengthening exercise on thigh muscle volume, pro- or anti-inflammatory cytokines, and immunocytes in the older adults: A randomized controlled trial

BACKGROUND

This study investigated the intensity-effects of strength training on thigh muscle mass, cytokines, and immunocytes in the older adults.

MATERIALS AND METHODS

A total of 81 participated in this study. Participants were assigned randomly to four groups: control group (CON), low- (LSE), moderate- (MSE), and high-intensity strength exercise (HSE) groups. Three exercise groups worked out for 50 min/day, 3 days/week for 12 weeks.

RESULTS

In the thigh volume analyzed by computed tomography, the exercise groups showed a significant increase in the muscle mass, with a clear pattern of change observed in the groups who exercised with moderate to high intensity. The lowest levels of interleukin (IL)-6 in the MSE group (-20.94%) and tumor necrosis factor-α in the HSE group (-28.75%) were observed. Notably, IL-10 showed a significant increase (35.72%) only in the MSE group. In the CON group, natural killer (NK) cells showed a decrease, while in the exercise groups, their levels increased. The highest levels of NK cells were observed in the HSE group. Similar patterns of change were observed in CD4 T cells and CD19 B cells. CD3 and CD8 T cells exhibited significant increases in the MSE and HSE groups.

CONCLUSIONS

This study presents evidence that engaging in moderate to high-intensity exercise may have a positive impact on cytokines and immunocytes by increasing muscle mass in older adults who may have sarcopenia.

SIMPLE SUMMARY

Engaging in strength training exercises is considered crucial for maintaining the health of older individuals who are susceptible to sarcopenia. When resistance exercises are performed at a moderate to strenuous intensity, it is anticipated that positive changes can occur in cytokines and immunocytes. These changes can be observed through improvements in thigh muscle volumes as measured by computed tomography.

Cytokine activity in Parkinson's disease

The contribution of the immune system to the pathophysiology of neurodegenerative Parkinson's disease (PD) is increasingly being recognised, with alterations in the innate and adaptive arms of the immune system underlying central and peripheral inflammation in PD. As chief modulators of the immune response, cytokines have been intensely studied in the field of PD both in terms of trying to understand their contribution to disease pathogenesis, and if they may comprise much needed therapeutic targets for a disease with no current modifying therapy. This review summarises current knowledge on key cytokines implicated in PD (TNFα, IL-6, IL-1β, IL-10, IL-4 and IL-1RA) that can modulate both pro-inflammatory and anti-inflammatory effects. Cytokine activity in PD is clearly a complicated process mediated by substantial cross-talk of signalling pathways and the need to balance pro- and anti-inflammatory effects. However, understanding cytokine activity may hold promise for unlocking new insight into PD and how it may be halted.

Oral administration of sophoricoside (SOP) inhibits neuronal damage and neuroinflammation to curb neurodegeneration in Parkinson's disease

Neuronal apoptosis and neuroinflammation are key factors involved in the pathological changes of Parkinson's disease (PD). Sophoricoside (SOP) has shown anti-inflammatory and anti-apoptosis effects in various diseases. However, the role of SOP in PD has not been reported. In this experiment, we found that oral administration of SOP alleviated weight loss and motor symptoms in 1-Methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-injected mice. Further studies revealed that SOP inhibited inflammatory responses and neuronal apoptosis in the midbrain region of MPTP-injected mice. In vitro mechanistic study, we found that SOP exerts neuroprotective effects through a two-sided action. On the one hand, SOP inhibits Lipopolysaccharide (LPS)-induced inflammatory responses in microglia by inhibiting the Nuclear factor kappa-B(NF-κB) pathway. On the other hand, SOP inhibits 1-methyl-4-phenylpyridinium (MPP+)-induced neuronal apoptosis by regulating the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway. Thus SOP is expected to be a potential therapeutic agent for PD by targeting neuroinflammation and neuronal apoptosis.

Vitamin B₁₂ deficiency and Parkinson’s disease

Parkinson’s disease (PD) is a progressive neurodegenerative disease with various clinical manifestations, its origin not always can be explained only by dopamine deficiency. Long-term treatment with levodopa (especially its intraduodenal administration), as well as clinical manifestations of polyneuropathy, cognitive deficits, postural disorders with freezing of gate, REM sleep behavioral disorders, are more often associated with vitamin B12 deficiency. Several reasons for this association and mechanisms of their development are discussed. Early detection of cobalamin deficiency in PD, especially in patients from high-risk groups, makes it possible to stop this pathological condition timely and prevent irreversible changes. Modern data on the use of high-dose (1000 μ g) oral vitamin B12 are presented, it has comparable clinical efficacy and significant advantages, compared with the parenteral form, in terms of the ease of use and the ability to avoid undesirable postinjection reactions.

Efficacy of a paper-based interleukin-6 test strip combined with a spectrum-based optical reader for sequential monitoring and early recognition of respiratory failure in elderly pneumonia-a pilot study

Introduction: Community-acquired pneumonia (CAP) is lethal in elderly individuals who are more vulnerable to respiratory failure and require more emergency ventilation support than younger individuals. Interleukin-6 (IL-6) plays a crucial role and has predictive value in CAP; high serum IL-6 concentrations in adults are associated with high respiratory failure and mortality rates. Early detection of IL-6 concentrations can facilitate the timely stratification of patients at risk of acute respiratory failure. However, conventional enzyme-linked immunosorbent assay (ELISA) IL-6 measurement is laborious and time-consuming. Methods: The IL-6 rapid diagnostic system combined with a lateral flow immunoassay-based (LFA-based) IL-6 test strip and a spectrum-based optical reader is a novel tool developed for rapid and sequential bedside measurements of serum IL-6 concentrations. Here, we evaluated the correlation between the IL-6 rapid diagnostic system and the ELISA and the efficacy of the system in stratifying high-risk elderly patients with CAP. Thirty-six elderly patients (median age: 86.5 years; range: 65-97 years) with CAP were enrolled. CAP diagnosis was established based on the Infectious Diseases Society of America (IDSA) criteria. The severity of pneumonia was assessed using the CURB-65 score and Pneumonia Severity Index (PSI). IL-6 concentration was measured twice within 24 h of admission. Results: The primary endpoint variable was respiratory failure requiring invasive mechanical or non-invasive ventilation support after admission. IL-6 rapid diagnostic readouts correlated with ELISA results (p < 0.0001) for 30 samples. Patients were predominantly male and bedridden (69.4%). Ten patients (27.7%) experienced respiratory failure during admission, and five (13.9%) died of pneumonia. Respiratory failure was associated with a higher mortality rate (p = 0.015). Decreased serum IL-6 concentration within 24 h after admission indicated a lower risk of developing respiratory failure in the later admission course (Receiver Operating Characteristic [ROC] curve = 0.696). Conclusion: Sequential IL-6 measurements with the IL-6 rapid diagnostic system might be useful in early clinical risk assessment and severity stratification of elderly patients with pneumonia. This system is a potential point-of-care diagnostic device for sequential serum IL-6 measurements that can be applied in variable healthcare systems.

Lewy bodies, iron, inflammation and neuromelanin: pathological aspects underlying Parkinson's disease

Since the description of some peculiar symptoms by James Parkinson in 1817, attempts have been made to define its cause or at least to enlighten the pathology of "Parkinson's disease (PD)." The vast majority of PD subtypes and most cases of sporadic PD share Lewy bodies (LBs) as a characteristic pathological hallmark. However, the processes underlying LBs generation and its causal triggers are still unknown. ɑ-Synuclein (ɑ-syn, encoded by the SNCA gene) is a major component of LBs, and SNCA missense mutations or duplications/triplications are causal for rare hereditary forms of PD. Thus, it is imperative to study ɑ-syn protein and its pathology, including oligomerization, fibril formation, aggregation, and spreading mechanisms. Furthermore, there are synergistic effects in the underlying pathogenic mechanisms of PD, and multiple factors-contributing with different ratios-appear to be causal pathological triggers and progression factors. For example, oxidative stress, reduced antioxidative capacity, mitochondrial dysfunction, and proteasomal disturbances have each been suggested to be causal for ɑ-syn fibril formation and aggregation and to contribute to neuroinflammation and neural cell death. Aging is also a major risk factor for PD. Iron, as well as neuromelanin (NM), show age-dependent increases, and iron is significantly increased in the Parkinsonian substantia nigra (SN). Iron-induced pathological mechanisms include changes of the molecular structure of ɑ-syn. However, more recent PD research demonstrates that (i) LBs are detected not only in dopaminergic neurons and glia but in various neurotransmitter systems, (ii) sympathetic nerve fibres degenerate first, and (iii) at least in "brain-first" cases dopaminergic deficiency is evident before pathology induced by iron and NM. These recent findings support that the ɑ-syn/LBs pathology as well as iron- and NM-induced pathology in "brain-first" cases are important facts of PD pathology and via their interaction potentiate the disease process in the SN. As such, multifactorial toxic processes posted on a personal genetic risk are assumed to be causal for the neurodegenerative processes underlying PD. Differences in ratios of multiple factors and their spatiotemporal development, and the fact that common triggers of PD are hard to identify, imply the existence of several phenotypical subtypes, which is supported by arguments from both the "bottom-up/dual-hit" and "brain-first" models. Therapeutic strategies are necessary to avoid single initiation triggers leading to PD.

Investigating Therapeutic Effects of Indole Derivatives Targeting Inflammation and Oxidative Stress in Neurotoxin-Induced Cell and Mouse Models of Parkinson's Disease

Neuroinflammation and oxidative stress have been emerging as important pathways contributing to Parkinson's disease (PD) pathogenesis. In PD brains, the activated microglia release inflammatory factors such as interleukin (IL)-β, IL-6, tumor necrosis factor (TNF)-α, and nitric oxide (NO), which increase oxidative stress and mediate neurodegeneration. Using 1-methyl-4-phenylpyridinium (MPP⁺)-activated human microglial HMC3 cells and the sub-chronic 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD, we found the potential of indole derivative NC009-1 against neuroinflammation, oxidative stress, and neurodegeneration for PD. In vitro, NC009-1 alleviated MPP⁺-induced cytotoxicity, reduced NO, IL-1β, IL-6, and TNF-α production, and suppressed NLR family pyrin domain containing 3 (NLRP3) inflammasome activation in MPP⁺-activated HMC3 cells. In vivo, NC009-1 ameliorated motor deficits and non-motor depression, increased dopamine and dopamine transporter levels in the striatum, and reduced oxidative stress as well as microglia and astrocyte reactivity in the ventral midbrain of MPTP-treated mice. These protective effects were achieved by down-regulating NLRP3, CASP1, iNOS, IL-1β, IL-6, and TNF-α, and up-regulating SOD2, NRF2, and NQO1. These results strengthen the involvement of neuroinflammation and oxidative stress in PD pathogenic mechanism, and indicate NC009-1 as a potential drug candidate for PD treatment.

Faecal metabolite deficit, gut inflammation and diet in Parkinson's disease: Integrative analysis indicates inflammatory response syndrome

BACKGROUND

Gut-brain axis is widely implicated in the pathophysiology of Parkinson's disease (PD). We take an integrated approach to considering the gut as a target for disease-modifying intervention, using continuous measurements of disease facets irrespective of diagnostic divide.

METHODS

We characterised 77 participants with diagnosed-PD, 113 without, by dietary/exogenous substance intake, faecal metabolome, intestinal inflammation, serum cytokines/chemokines, clinical phenotype including colonic transit time. Complete-linkage hierarchical cluster analysis of metabolites discriminant for PD-status was performed.

RESULTS

Longer colonic transit was linked to deficits in faecal short-chain-fatty acids outside PD, to a 'tryptophan-containing metabolite cluster' overall. Phenotypic cluster analysis aggregated colonic transit with brady/hypokinesia, tremor, sleep disorder and dysosmia, each individually associated with tryptophan-cluster deficit. Overall, a faster pulse was associated with deficits in a metabolite cluster including benzoic acid and an imidazole-ring compound (anti-fungals) and vitamin B3 (anti-inflammatory) and with higher serum CCL20 (chemotactic for lymphocytes/dendritic cells towards mucosal epithelium). The faster pulse in PD was irrespective of postural hypotension. The benzoic acid-cluster deficit was linked to (well-recognised) lower caffeine and alcohol intakes, tryptophan-cluster deficit to higher maltose intake. Free-sugar intake was increased in PD, maltose intake being 63% higher (p = .001). Faecal calprotectin was 44% (95% CI 5%, 98%) greater in PD [p = .001, adjusted for proton-pump inhibitors (p = .001)], with 16% of PD-probands exceeding a cut-point for clinically significant inflammation compatible with inflammatory bowel disease. Higher maltose intake was associated with exceeding this calprotectin cut-point.

CONCLUSIONS

Emerging picture is of (i) clinical phenotype being described by deficits in microbial metabolites essential to gut health; (ii) intestinal inflammation; (iii) a systemic inflammatory response syndrome.

Serum inflammatory cytokines levels and the correlation analyses in Parkinson's disease

Objective: To investigate the serum levels of inflammatory cytokines and the correlations with Parkinson's disease (PD) clinical symptoms. Methods: Serum levels of the cytokines, including IL-6, IL-8, and TNF-α, were measured in 273 PD patients and 91 healthy controls (HCs). The clinical manifestations of PD were assessed with nine different scales to evaluate the cognitive function, non-motor symptoms, motor symptoms, and disease severity. The differences in these inflammatory indicators were examined between PD patients and HCs, and the correlations of these inflammatory indicators with clinical variables were analyzed in PD patients. Results: Serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in PD patients were higher than those in HCs, but serum interleukin-8 (IL-8) level was not significantly different from that in HCs. In PD patients, serum IL-6 level was positively correlated with age of onset, the Hamilton Depression Scale (HAMD), and the Non-Motor Symptom Scale (NMSS), UPDRS part I, part II, and part III, but it was inversely correlated with the Frontal Assessment Battery (FAB) and the Montreal Cognitive Assessment (MoCA) scores. Serum TNF-α level was positively correlated with age of onset and H&Y stage in PD patients (p = .037), but negatively correlated with FAB scores in PD patients (p = .010). However, no associations were found between all the clinical variables and the serum IL-8 level. The forward binary logistic regression model revealed that serum IL-6 level was associated with MoCA (p = .023) and UPDRS I scores (p = .023), but no associations was found with the remaining factors. The ROC curve of TNF-α for the diagnosis of PD showed the area under the curve (AUC) was .719 (p < .05, 95% CI: .655-.784), and the critical value of TNF-α was 5.380 pg/ml, with a diagnostic sensitivity of 76.0% and a specificity of 59.3%. Conclusion: Our results suggest increased serum levels of IL-6 and TNF-α in PD, we further found that IL-6 level was associated with non-motor symptoms and cognitive dysfunction, and IL-6 may play a role in the pathophysiology of non-motor symptoms in PD. At the same time, we also propose that TNF-α has a good diagnostic value for PD despite its irrelevance to clinical symptoms.

Neuroprotective Effect of Swertiamarin in a Rotenone Model of Parkinson's Disease: Role of Neuroinflammation and Alpha-Synuclein Accumulation

Parkinson's disease (PD) is a progressive neurodegenerative disease with no permanent cure affecting around 1% of the population over 65. There is an urgency to search for a disease-modifying agent with fewer untoward effects. PD pathology involves the accumulation of toxic alpha-synuclein (α-syn) and neuronal inflammation leading to the degeneration of dopaminergic (DAergic) neurons. Swertiamarin (SWE), a well-studied natural product, possesses a strong anti-inflammatory effect. It is a secoiridoid glycoside isolated from Enicostemma littorale Blume. SWE showed a reversal effect on the α-syn accumulation in the 6-hydroxydopamine (6-OHDA)-induced Caenorhabditis elegans model of PD. However, there are no reports in the literature citing the effect of SWE as a neuroprotective agent in rodents. The present study aimed to evaluate the anti-inflammatory activity of SWE against lipopolysaccharide (LPS)-induced C6 glial cell activation and its neuroprotective effect in the intrastriatal rotenone mouse PD model. SWE treatment showed a significant reduction in interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) levels in LPS-induced C6 glial cell activation. Further, our studies demonstrated the suppression of microglial and astroglial activation in substantia nigra (SN) after administration of SWE (100 mg/kg, intraperitoneally) in a rotenone mouse model. Moreover, SWE alleviated the rotenone-induced α-syn overexpression in the striatum and SN. SWE ameliorated the motor impairment against rotenone-induced neurotoxicity and mitigated the loss of DAergic neurons in the nigrostriatal pathway. Therefore, SWE has the potential to develop as an adjunct therapy for PD, but it warrants further mechanistic studies.

Pathogenesis of α-Synuclein in Parkinson's Disease: From a Neuron-Glia Crosstalk Perspective

Parkinson's disease (PD) is a progressive neurodegenerative disorder. The classical behavioral defects of PD patients involve motor symptoms such as bradykinesia, tremor, and rigidity, as well as non-motor symptoms such as anosmia, depression, and cognitive impairment. Pathologically, the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN) and the accumulation of α-synuclein (α-syn)-composed Lewy bodies (LBs) and Lewy neurites (LNs) are key hallmarks. Glia are more than mere bystanders that simply support neurons, they actively contribute to almost every aspect of neuronal development and function; glial dysregulation has been implicated in a series of neurodegenerative diseases including PD. Importantly, amounting evidence has added glial activation and neuroinflammation as new features of PD onset and progression. Thus, gaining a better understanding of glia, especially neuron-glia crosstalk, will not only provide insight into brain physiology events but also advance our knowledge of PD pathologies. This review addresses the current understanding of α-syn pathogenesis in PD, with a focus on neuron-glia crosstalk. Particularly, the transmission of α-syn between neurons and glia, α-syn-induced glial activation, and feedbacks of glial activation on DA neuron degeneration are thoroughly discussed. In addition, α-syn aggregation, iron deposition, and glial activation in regulating DA neuron ferroptosis in PD are covered. Lastly, we summarize the preclinical and clinical therapies, especially targeting glia, in PD treatments.

DA5-CH and Semaglutide Protect against Neurodegeneration and Reduce α-Synuclein Levels in the 6-OHDA Parkinson's Disease Rat Model

Insulin desensitization has been observed in the brains of patients with Parkinson's disease (PD), which is a progressive neurodegenerative disorder for which there is no cure. Semaglutide is a novel long-actingglucagon-likepeptide-1 (GLP-1) receptor agonist that is on the market as a treatment for type 2 diabetes. It is in a phase II clinical trial in patients with PD. Two previous phase II trials in PD patients showed good effects with the older GLP-1 receptor agonists, exendin-4 and liraglutide. We have developed a dual GLP-1/GIP receptor agonist (DA5-CH) that can cross the blood-brain barrier (BBB) at a higher rate than semaglutide. We tested semaglutide and DA5-CH in the 6-OHDA-lesion rat model of PD. Treatment was semaglutide or DA5-CH (25 nmol/kg, i.p.) daily for 30 days postlesion. Both drugs reduced the apomorphine-induced rotational behavior and alleviated dopamine depletion and the inflammation response in the lesioned striatum as shown in reduced IL-1β and TNF-α levels, with DA5-CH being more effective. In addition, both drugs protected dopaminergic neurons and increased TH expression in the substantia nigra. Furthermore, the level of monomer and aggregated α-synuclein was reduced by the drugs, and insulin resistance as shown in reduced pIRS-1ser312 phosphorylation was also attenuated after drug treatment, with DA5-CH being more effective. Therefore, while semaglutide showed good effects in this PD model, DA5-CH was superior and may be a better therapeutic drug for neurodegenerative disorders such as PD than GLP-1 receptor agonists that do not easily cross the BBB.

Genome integrity and inflammation in the nervous system

Preservation of genomic integrity is crucial for nervous system development and function. DNA repair deficiency results in several human diseases that are characterized by both neurodegeneration and neuroinflammation. Recent research has highlighted a role for compromised genomic integrity as a key factor driving neuropathology and triggering innate immune signaling to cause inflammation. Here we review the mechanisms by which DNA damage engages innate immune signaling and how this may promote neurological disease. We also consider the contributions of different neural cell types towards DNA damage-driven neuroinflammation. A deeper knowledge of genome maintenance mechanisms that prevent aberrant immune activation in neural cells will guide future therapies to ameliorate neurological disease.

Increased risk of sleep-related movement disorder in patients with Helicobacter pylori infection: A nationwide population-based study

Background and purpose

Evidence increasingly suggests that Helicobacter pylori infection (HPI) is associated with movement disorders such as Parkinson's disease (PD). However, the relationship between HPI and sleep-related movement disorders (SRMD) remains unknown. This nationwide population-based study tried to demonstrate whether patients with HPI have a higher risk of developing SRMD in a general adult population.

Methods

The study cohort enrolled 9,393 patients who were initially diagnosed with HPI between 2000 and 2013. Notably, 37,572 age- and sex-matched controls without prior HPI were selected as the reference. A Cox proportional hazard regression analysis was performed for multivariate adjustment.

Results

Patients with HPI had a higher risk of developing SRMD (adjusted hazard ratio [HR] = 2.18, 95% confidence interval [CI] = 1.26–3.82, p < 0.01). Patients with HPI aged ≥65 years exhibited the highest risk (HR = 3.01, 95% CI = 1.90–5.30, p < 0.001), followed by patients aged 45–64 years (HR = 1.69, 95% CI = 1.26–2.90, p <0.01) and <45 years (HR = 1.49, 95% CI = 1.12–2.49, p < 0.01). Patients were most likely to develop SRMD 5 years or more after diagnosis of HPI (HR = 3.33, 95% CI = 1.97–5.89, p < 0.001). The increased risk of SRMD in male patients with HPI (HR = 2.73, 95% CI = 1.53–4.79, p < 0.001) was greater than in female patients (HR = 1.14, 95% CI = 1.04–1.65, p < 0.05).

Conclusion

Patients with HPI were associated with an increased risk for SRMD, with a higher risk in men, aged ≥65 years, and diagnosed for more than 5 years.

The role of the adaptive immune system and T cell dysfunction in neurodegenerative diseases

The adaptive immune system and associated inflammation are vital in surveillance and host protection against internal and external threats, but can secondarily damage host tissues. The central nervous system is immune-privileged and largely protected from the circulating inflammatory pathways. However, T cell involvement and the disruption of the blood-brain barriers have been linked to several neurodegenerative diseases including Parkinson's disease, Alzheimer's disease, and multiple sclerosis. Under normal physiological conditions, regulatory T cells (Treg cells) dampen the inflammatory response of effector T cells. In the pathological states of many neurodegenerative disorders, the ability of Treg cells to mitigate inflammation is reduced, and a pro-inflammatory environment persists. This perspective review provides current knowledge on the roles of T cell subsets (e.g., effector T cells, Treg cells) in neurodegenerative and ocular diseases, including uveitis, diabetic retinopathy, age-related macular degeneration, and glaucoma. Many neurodegenerative and ocular diseases have been linked to immune dysregulation, but the cellular events and molecular mechanisms involved in such processes remain largely unknown. Moreover, the role of T cells in ocular pathologies remains poorly defined and limited literature is available in this area of research. Adoptive transfer of Treg cells appears to be a vital immunological approach to control ocular pathologies. Similarities in T cell dysfunction seen among non-ocular neurodegenerative diseases suggest that this area of research has a great potential to develop better therapeutic agents for ocular diseases and warrants further studies. Overall, this perspective review article provides significant information on the roles of T cells in numerous ocular and non-ocular neurodegenerative diseases.

Neuroinflammation and Parkinson's Disease-From Neurodegeneration to Therapeutic Opportunities

Parkinson’s disease (PD) is the second most prevalent neurodegenerative disorder worldwide. Clinically, it is characterized by a progressive degeneration of dopaminergic neurons (DAn), resulting in severe motor complications. Preclinical and clinical studies have indicated that neuroinflammation can play a role in PD pathophysiology, being associated with its onset and progression. Nevertheless, several key points concerning the neuroinflammatory process in PD remain to be answered. Bearing this in mind, in the present review, we cover the impact of neuroinflammation on PD by exploring the role of inflammatory cells (i.e., microglia and astrocytes) and the interconnections between the brain and the peripheral system. Furthermore, we discuss both the innate and adaptive immune responses regarding PD pathology and explore the gut–brain axis communication and its influence on the progression of the disease.

Management of Helicobacter pylori infection: the Maastricht VI/Florence consensus report

Helicobacter pyloriInfection is formally recognised as an infectious disease, an entity that is now included in the International Classification of Diseases 11th Revision. This in principle leads to the recommendation that all infected patients should receive treatment. In the context of the wide clinical spectrum associated with Helicobacter pylori gastritis, specific issues persist and require regular updates for optimised management.The identification of distinct clinical scenarios, proper testing and adoption of effective strategies for prevention of gastric cancer and other complications are addressed. H. pylori treatment is challenged by the continuously rising antibiotic resistance and demands for susceptibility testing with consideration of novel molecular technologies and careful selection of first line and rescue therapies. The role of H. pylori and antibiotic therapies and their impact on the gut microbiota are also considered.Progress made in the management of H. pylori infection is covered in the present sixth edition of the Maastricht/Florence 2021 Consensus Report, key aspects related to the clinical role of H. pylori infection were re-evaluated and updated. Forty-one experts from 29 countries representing a global community, examined the new data related to H. pylori infection in five working groups: (1) indications/associations, (2) diagnosis, (3) treatment, (4) prevention/gastric cancer and (5) H. pylori and the gut microbiota. The results of the individual working groups were presented for a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in various clinical fields.

Peripheral inflammatory cytokines and motor symptoms in persons with Parkinson's disease

Background

Many of the motor symptoms of Parkinson's disease (PD) impact quality of life and are not fully ameliorated by current pharmacological and surgical treatments. A better understanding of the pathophysiology underlying these symptoms is needed. Previous research has suggested that inflammation may play a significant role in PD pathophysiology and progression, but there is limited research exploring how inflammation directly relates to motor symptoms in PD. Thus, the purpose of this study was to evaluate associations between peripheral immune inflammatory markers and motor symptoms of PD, specifically, tremor, bradykinesia, and postural and gait instability. We hypothesized that peripheral inflammatory cytokines would predict the severity of motor symptoms in persons with PD, and that there will be higher levels of peripheral inflammatory cytokine markers in persons with PD when compared to age-matched healthy older adults.

Methods

Twenty-six participants with PD and fourteen healthy older adults completed the study. For participants with PD, the motor section of the Unified Parkinson's Disease Rating Scale (UPDRS) was recorded and scored by two Movement Disorders Neurologists masked to the study. A blood sample was collected from both participants with PD and the healthy older adults. Through the MILLIPLEX® map High Sensitivity Human Cytokine Kit, key inflammation-related markers were analyzed (TNF-α, IFN-γ, IL-1β, IL-8, IL-2, IL-7, IL-5, IL-13, IL, 4, IL-10 IL-12p70, GM-CSF, and IL-6).

Results

Results revealed significantly higher levels of IL-6 in persons with PD when compared to healthy older adults (p ​= ​0.005). Moreover, results revealed that higher levels of IL-4 (p ​= ​0.011) and lower levels of IFNγ (p ​= ​0.003) significantly predicted more severe tremor in persons with PD. No other associations between the peripheral inflammation markers and other motor symptoms were observed.

Conclusions

Overall, these results are consistent with a growing body of literature that implicates inflammatory cytokines in the PD, and further suggests that inflammatory cytokines, or lack thereof, may be associated with tremor in persons with PD.

Biomarker of Neuroinflammation in Parkinson's Disease

Parkinson's disease (PD) is caused by abnormal accumulation of α-synuclein in dopaminergic neurons of the substantia nigra, which subsequently causes motor symptoms. Neuroinflammation plays a vital role in the pathogenesis of neurodegeneration in PD. This neuroinflammatory neurodegeneration involves the activation of microglia, upregulation of proinflammatory factors, and gut microbiota. In this review, we summarized the recent findings on detection of PD by using inflammatory biomarkers, such as interleukin (IL)-1β, IL-2, IL-6, IL-10, tumor necrosis factor (TNF)-α; regulated upon activation, normal T cell expressed and presumably secreted (RANTES) and high-sensitivity c-reactive protein (hsCRP); and radiotracers such as [11C]PK11195 and [18F]-FEPPA, as well as by monitoring disease progression and the treatment response. Many PD-causing mutations in SNCA, LRRK2, PRKN, PINK1, and DJ-1 are also associated with neuroinflammation. Several anti-inflammatory medications, including nonsteroidal anti-inflammatory drugs (NSAID), inhibitors of TNF-α and NLR family pyrin domain containing 3 (NLRP3), agonists of nuclear factor erythroid 2-related factor 2 (NRF2), peroxisome proliferator-activated receptor gamma (PPAR-γ), and steroids, have demonstrated neuroprotective effects in in vivo or in vitro PD models. Clinical trials applying objective biomarkers are required to investigate the therapeutic potential of anti-inflammatory medications for PD.

Neuroinflammation Upregulated Neuronal Toll-Like Receptors 2 and 4 to Drive Synucleinopathy in Neurodegeneration

Background: Parkinson’s disease (PD) is characterized by intraneuronal α-synuclein aggregation called Lewy bodies and progressive dopaminergic neurodegeneration. Toll-like receptor (TLR) signaling is a major pathway mediating inflammation. The molecular link on how neuroinflammation upregulates neuronal TLRs and induces accumulation of α-synuclein aggregates to drive synucleinopathy remains to be determined.

Objective: Despite conditioned medium from microglia and TLR agonists were utilized to study their effects on neuronal cells, a Transwell coculture system, comprising lipopolysaccharide-activated microglia on top and retinoic acid-differentiated SH-SY5Y cells at the bottom more mimicking in vivo neuroinflammation, was employed to elucidate the mechanism of activated microglia on neuronal cells.

Methods: Genetic variants of TLRs in PD patients were genotyped and the multiplex cytokines, sRAGE, and HMGB1were assessed. A coculture system was employed to measure α-synuclein aggregates and neurite shortening by confocal microscope. The expression of TLR2/4 and autophagy flux was detected by western blot and immunofluorescence.

Results: PD patients showed higher plasma levels of proinflammatory cytokines and genetic TLR4 variant, c.896 A > G (p. D299G). Elevated proinflammatory cytokines in coculture medium was also seen. Phosphorylation and aggregation of α-synuclein, shortening of neurite, upregulation of TLR2/4 expression, activation of downstream p38 and JNK, and dampening of autophagic flux were seen in SH-SY5Y cells cocultured with activated microglia. Those were prevented by inhibiting TLR2/4 and p38/JNK signaling.

Conclusion: Activated microglia-derived neuroinflammation induced neuronal TLR2/4-p38/JNK activation to perturb autophagy, causing accumulation of α-synuclein aggregates and neurite shortening. Targeting neuronal TLR2/4 pathway might be a mechanistic-based therapy for neurodegenerative disease, such as PD.

Amelioration of oxidative stress utilizing nanoemulsion loaded with bromocriptine and glutathione for the management of Parkinson's disease

Parkinson's disease (PD) is triggered by the formation of free radicals in dopaminergic neurons, which results in oxidative stress-induced neurodegeneration. The objective of the work was to relieve oxidative stress by employing intranasal delivery of Bromocriptine Mesylate (BRM) and Glutathione (GSH) loaded nanoemulsion for the better management of PD. The depth of permeation of the nanoemulsion was assessed through confocal laser scanning microscopy (CLSM) which revealed higher nanoemulsion permeation in contrast to suspension. Biocompatibility of nanoemulsion was confirmed by nasal cilio toxicity study. The DPPH study showed that the nanoemulsion had significant antioxidant activity. Biochemical estimation studies in Wistar rats were carried out in order to determine the effect of nanoemulsion on oxidative stress. The levels of GSH, superoxide dismutase (SOD), and catalase (CAT) were significantly enhanced; and the level of thiobarbituric acid reactive substances (TBARS) was significantly reduced after the intranasal administration of nanoemulsion in the haloperidol-induced model of PD. Furthermore, the levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were also determined which reduced significantly after the administration of nanoemulsion. The oxidative stress levels were lowered with nanoemulsion, showing the combined antioxidant capability of BRM and GSH. The neuroprotective effect of the prepared nanoemulsion was confirmed by histopathological studies. Pharmacokinetic study revealed a higher concentration of BRM and GSH in the brain of Wistar rats after intranasal administration of nanoemulsion with a higher Brain/Plasma ratio. A higher value of AUC_(0-8) of nanoemulsion in the brain after intranasal administration revealed that BRM and GSH remained in the brain for a longer period due to sustained release from nanoemulsion. According to the findings, BRM and GSH loaded nanoemulsion has the potential to provide a combined and synergistic anti-oxidant effect for efficient management of PD.

Is the Use of Glyphosate in Modern Agriculture Resulting in Increased Neuropsychiatric Conditions Through Modulation of the Gut-brain-microbiome Axis?

Environmental exposure to glyphosate and glyphosate-based herbicides has the potential to negatively influence neurodevelopment and behavior across generations indirectly through the gut-brain-microbiome axis. Potential mechanisms by which glyphosate may elicit these effects are through the disruption of the normally symbiotic relationship of the host and the gut microbiome. Given glyphosate can kill commensal members of the microbiome like Lactobacillus spp., Ruminococaeae and Butyricoccus spp., resulting in reductions in key microbial metabolites that act through the gut-brain-microbiome axis including indoles, L-glutamate and SCFAs. Glyphosate- resistant microbes in the gut have the potential to increase the production of pro-inflammatory cytokines and reactive oxygen species which may result in increased HPA activation, resulting in increased production of glucocorticoids which have implications on neurodevelopment. In addition, maternal transfer of the gut microbiome can affect immune and neurodevelopment, across generations. This perspective article weighs the evidence for chronic glyphosate exposure on the gut microbiome and the potential consequences on the gut-brain axis correlated with increased incidence of neuropsychiatric conditions.

Role of Mitochondrial Nucleic Acid Sensing Pathways in Health and Patho-Physiology

Mitochondria, in symbiosis with the host cell, carry out a wide variety of functions from generating energy, regulating the metabolic processes, cell death to inflammation. The most prominent function of mitochondria relies on the oxidative phosphorylation (OXPHOS) system. OXPHOS heavily influences the mitochondrial-nuclear communication through a plethora of interconnected signaling pathways. Additionally, owing to the bacterial ancestry, mitochondria also harbor a large number of Damage Associated Molecular Patterns (DAMPs). These molecules relay the information about the state of the mitochondrial health and dysfunction to the innate immune system. Consequently, depending on the intracellular or extracellular nature of detection, different inflammatory pathways are elicited. One group of DAMPs, the mitochondrial nucleic acids, hijack the antiviral DNA or RNA sensing mechanisms such as the cGAS/STING and RIG-1/MAVS pathways. A pro-inflammatory response is invoked by these signals predominantly through type I interferon (T1-IFN) cytokines. This affects a wide range of organ systems which exhibit clinical presentations of auto-immune disorders. Interestingly, tumor cells too, have devised ingenious ways to use the mitochondrial DNA mediated cGAS-STING-IRF3 response to promote neoplastic transformations and develop tumor micro-environments. Thus, mitochondrial nucleic acid-sensing pathways are fundamental in understanding the source and nature of disease initiation and development. Apart from the pathological interest, recent studies also attempt to delineate the structural considerations for the release of nucleic acids across the mitochondrial membranes. Hence, this review presents a comprehensive overview of the different aspects of mitochondrial nucleic acid-sensing. It attempts to summarize the nature of the molecular patterns involved, their release and recognition in the cytoplasm and signaling. Finally, a major emphasis is given to elaborate the resulting patho-physiologies.

T cells, α-synuclein and Parkinson disease

The notion that autoimmune responses to α-synuclein may be involved in the pathogenesis of this disorder stems from reports that mutations in α-synuclein or certain alleles of the major histocompatibility complex (MHC) are associated with the disease and that dopaminergic and norepinephrinergic neurons in the midbrain can present antigenic epitopes. Here, we discuss recent evidence that a defined set of peptides derived from α-synuclein act as antigenic epitopes displayed by specific MHC alleles and drive helper and cytotoxic T cell responses in patients with PD. Moreover, phosphorylated α-synuclein may activate T cell responses in a less restricted manner in PD. While the roles for the acquired immune system in disease pathogenesis remain unknown, preclinical animal models and in vitro studies indicate that T cells may interact with neurons and exert effects related to neuronal death and neuroprotection. These findings suggest that therapeutics that target T cells and ameliorate the incidence or disease severity of inflammatory bowel disorders or CNS autoimmune diseases such as multiple sclerosis may be useful in PD.

A Comprehensive Review on the Role of the Gut Microbiome in Human Neurological Disorders

The human body is full of an extensive number of commensal microbes, consisting of bacteria, viruses, and fungi, collectively termed the human microbiome. The initial acquisition of microbiota occurs from both the external and maternal environments, and the vast majority of them colonize the gastrointestinal tract (GIT). These microbial communities play a central role in the maturation and development of the immune system, the central nervous system, and the GIT system and are also responsible for essential metabolic pathways. Various factors, including host genetic predisposition, environmental factors, lifestyle, diet, antibiotic or nonantibiotic drug use, etc., affect the composition of the gut microbiota. Recent publications have highlighted that an imbalance in the gut microflora, known as dysbiosis, is associated with the onset and progression of neurological disorders. Moreover, characterization of the microbiome-host cross talk pathways provides insight into novel therapeutic strategies. Novel preclinical and clinical research on interventions related to the gut microbiome for treating neurological conditions, including autism spectrum disorders, Parkinson's disease, schizophrenia, multiple sclerosis, Alzheimer's disease, epilepsy, and stroke, hold significant promise. This review aims to present a comprehensive overview of the potential involvement of the human gut microbiome in the pathogenesis of neurological disorders, with a particular emphasis on the potential of microbe-based therapies and/or diagnostic microbial biomarkers. This review also discusses the potential health benefits of the administration of probiotics, prebiotics, postbiotics, and synbiotics and fecal microbiota transplantation in neurological disorders.

The effect of exercise on cytokines: implications for musculoskeletal health: a narrative review

The physiological effects of physical exercise are ubiquitously reported as beneficial to the cardiovascular and musculoskeletal systems. Exercise is widely promoted by medical professionals to aid both physical and emotional wellbeing; however, mechanisms through which this is achieved are less well understood. Despite numerous beneficial attributes, certain types of exercise can inflict significant significant physiological stress. Several studies document a key relationship between exercise and immune activation. Activation of the innate immune system occurs in response to exercise and it is proposed this is largely mediated by cytokine signalling. Cytokines are typically classified according to their inflammatory properties and evidence has shown that cytokines expressed in response to exercise are diverse and may act to propagate, modulate or mitigate inflammation in musculoskeletal health. The review summarizes the existing literature on the relationship between exercise and the immune system with emphasis on how exercise-induced cytokine expression modulates inflammation and the immune response.

Dopaminergic neuronal death in the substantia nigra associates with change in serum levels of TNF-α and IL-1β; evidence from early experimental model of Parkinson's disease

PURPOSE

Studies have shown that inflammation plays a key role in etiology of Parkinson's disease (PD). However, human studies which have evaluated association between PD and serum levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) have reported conflicting results. In this study, serum and striatum levels of these cytokines were evaluated in 6-hydroxydopamine (6-OHDA) animal model of PD.

METHOD

The neurotoxin of 6-OHDA was injected into medial forebrain bundle of right hemisphere and behavioral tests were carried out to eight weeks thereafter to evaluate severity of PD and its progress. Blood was collected before the toxin and in second and eight weeks after that. Survival of dopaminergic (DAergic) neurons in substantia nigra was assessed by immunohistochemistry. TNF-α and IL-1β levels were determined using ELISA kits.

RESULT

Severity of behavioral symptoms was gradually increased in 6-OHDA-treated rats. They showed a decrease in serum TNF-α level in the eight week and increase in IL-1β both in the second and eight weeks. They were divided into two subgroups, symptomatic and asymptomatic with severe and moderate degrees in DAergic neuronal death. Significant decrease in serum TNF-α was only observed in the symptomatic subgroup but IL-1β increased in both subgroups. Also, striatal levels of both cytokines were higher in the lesioned hemisphere.

CONCLUSION

Increase in serum IL-1β level can reflect moderate degree of lesion in substantia nigra and thereby is used for prognosis of PD before its clinical symptoms are appeared. On the other hand, an increase in serum TNF-α is appeared in advanced stage of PD.

Multi-omic insights into Parkinson's Disease: From genetic associations to functional mechanisms

Genome-Wide Association Studies (GWAS) have elucidated the genetic components of Parkinson's Disease (PD). However, because the vast majority of GWAS association signals fall within non-coding regions, translating these results into an interpretable, mechanistic understanding of the disease etiology remains a major challenge in the field. In this review, we provide an overview of the approaches to prioritize putative causal variants and genes as well as summarise the primary findings of previous studies. We then discuss recent efforts to integrate multi-omics data to identify likely pathogenic cell types and biological pathways implicated in PD pathogenesis. We have compiled full summary statistics of cell-type, tissue, and phentoype enrichment analyses from multiple studies of PD GWAS and provided them in a standardized format as a resource for the research community (https://github.com/RajLabMSSM/PD_omics_review). Finally, we discuss the experimental, computational, and conceptual advances that will be necessary to fully elucidate the effects of functional variants and genes on cellular dysregulation and disease risk.

Mitochondrial dysfunction in adult midbrain dopamine neurons triggers an early immune response

Dopamine (DA) neurons of the midbrain are at risk to become affected by mitochondrial damage over time and mitochondrial defects have been frequently reported in Parkinson’s disease (PD) patients. However, the causal contribution of adult-onset mitochondrial dysfunction to PD remains uncertain. Here, we developed a mouse model lacking Mitofusin 2 (MFN2), a key regulator of mitochondrial network homeostasis, in adult midbrain DA neurons. The knockout mice develop severe and progressive DA neuron-specific mitochondrial dysfunction resulting in neurodegeneration and parkinsonism. To gain further insights into pathophysiological events, we performed transcriptomic analyses of isolated DA neurons and found that mitochondrial dysfunction triggers an early onset immune response, which precedes mitochondrial swelling, mtDNA depletion, respiratory chain deficiency and cell death. Our experiments show that the immune response is an early pathological event when mitochondrial dysfunction is induced in adult midbrain DA neurons and that neuronal death may be promoted non-cell autonomously by the cross-talk and activation of surrounding glial cells.

Parkinson’s disease (PD) is a common neurodegenerative disorder characterized by progressive loss of dopamine (DA)-producing neurons and strongly compromised motor performance. Multiple observations suggest that DA neurons are particularly prone to acquire mitochondrial damage in adult life. This acquired mitochondrial dysfunction likely impairs DA neuron function and contributes to cell death. To study the consequences of adult-onset mitochondrial dysfunction in DA neurons, we generated a conditional activatable knockout mouse model lacking Mitofusin 2, a key regulator of mitochondrial homeostasis. This animal model allows the induction of mitochondrial dysfunction selectively in adult DA neurons and leads to motor defects and the typical pattern of neurodegeneration seen in PD. By studying gene expression in isolated DA neurons at early disease stages and by using in situ approaches on brain sections, we report an early onset of an inflammatory response. Inflammation is present already when the mutant DA neurons display the first signs of mitochondrial fragmentation and precedes the onset of respiratory chain dysfunction and neurodegeneration. The inflammatory response in DA neurons and activation of surrounding glia thus likely exacerbates or drives the neurodegenerative process in this animal model of adult-onset PD.

Age, sex, and inflammatory markers predict chronic conditions, cardiac disease, and mortality among captive western lowland gorillas (Gorilla gorilla gorilla)

In humans, inflammatory markers predict health risks. As great apes experience many similar conditions, measuring inflammation may provide valuable health information. We examined four serum inflammatory markers in zoo-housed gorillas (n = 48): albumin, CRP, IL-6, and TNF-α. We first analyzed age- and sex-associated patterns, then used multimodel inference to evaluate models with age, sex, and inflammatory markers as predictors of all-cause morbidity, cardiac disease, and mortality. Older gorillas had lower albumin and higher IL-6, and males had higher albumin, lower CRP, and lower TNF-α. All-cause morbidity was best predicted by age, sex, and TNF-α, but the second model containing only age and sex was equivalent. Cardiac disease was best predicted by TNF-α alongside age and sex, with lower levels associated with increased risk. When outliers were removed, the model with TNF-α was second to the model containing only age and sex. Finally, mortality risk was best predicted by the model with only age and sex. Other models containing individual inflammatory markers were within top model sets for each health outcome. Our results indicate that age and sex are robust for predicting all-cause morbidity and mortality risk in gorillas; while models which include individual inflammatory markers also predict risk, they may not improve predictions over age and sex alone. However, given the prevalence of cardiac disease in great apes, these results suggest that TNF-α warrants further investigation. With their potential to provide valuable health information, data on inflammatory markers may contribute to the care and management of gorillas in human care.

Molecular Communication Between Neuronal Networks and Intestinal Epithelial Cells in Gut Inflammation and Parkinson's Disease

Intestinal symptoms, such as nausea, vomiting, and constipation, are common in Parkinson's disease patients. These clinical signs normally appear years before the diagnosis of the neurodegenerative disease, preceding the occurrence of motor manifestations. Moreover, it is postulated that Parkinson's disease might originate in the gut, due to a response against the intestinal microbiota leading to alterations in alpha-synuclein in the intestinal autonomic nervous system. Transmission of this protein to the central nervous system is mediated potentially via the vagus nerve. Thus, deposition of aggregated alpha-synuclein in the gastrointestinal tract has been suggested as a potential prodromal diagnostic marker for Parkinson's disease. Interestingly, hallmarks of chronic intestinal inflammation in inflammatory bowel disease, such as dysbiosis and increased intestinal permeability, are also observed in Parkinson's disease patients. Additionally, alpha-synuclein accumulations were detected in the gut of Crohn's disease patients. Despite a solid association between neurodegenerative diseases and gut inflammation, it is not clear whether intestinal alterations represent cause or consequence of neuroinflammation in the central nervous system. In this review, we summarize the bidirectional communication between the brain and the gut in the context of Parkinson's disease and intestinal dysfunction/inflammation as present in inflammatory bowel disease. Further, we focus on the contribution of intestinal epithelium, the communication between intestinal epithelial cells, microbiota, immune and neuronal cells, as well as mechanisms causing alterations of epithelial integrity.

Mitochondrial DNA Heteroplasmy as an Informational Reservoir Dynamically Linked to Metabolic and Immunological Processes Associated with COVID-19 Neurological Disorders

Mitochondrial DNA (mtDNA) heteroplasmy is the dynamically determined co-expression of wild type (WT) inherited polymorphisms and collective time-dependent somatic mutations within individual mtDNA genomes. The temporal expression and distribution of cell-specific and tissue-specific mtDNA heteroplasmy in healthy individuals may be functionally associated with intracellular mitochondrial signaling pathways and nuclear DNA gene expression. The maintenance of endogenously regulated tissue-specific copy numbers of heteroplasmic mtDNA may represent a sensitive biomarker of homeostasis of mitochondrial dynamics, metabolic integrity, and immune competence. Myeloid cells, monocytes, macrophages, and antigen-presenting dendritic cells undergo programmed changes in mitochondrial metabolism according to innate and adaptive immunological processes. In the central nervous system (CNS), the polarization of activated microglial cells is dependent on strategically programmed changes in mitochondrial function. Therefore, variations in heteroplasmic mtDNA copy numbers may have functional consequences in metabolically competent mitochondria in innate and adaptive immune processes involving the CNS. Recently, altered mitochondrial function has been demonstrated in the progression of coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Accordingly, our review is organized to present convergent lines of empirical evidence that potentially link expression of mtDNA heteroplasmy by functionally interactive CNS cell types to the extent and severity of acute and chronic post-COVID-19 neurological disorders.

High Inflammatory Tendency Induced by Malignant Stimulation Through Imbalance of CD28 and CTLA-4/PD-1 Contributes to Dopamine Neuron Injury

Background

Parkinson’s disease is a common neurodegenerative disease in the elderly. The incidence of various cancers in Parkinson’s disease patients is significantly lower than in healthy people. Parkinson’s disease patients are individuals with a high tendency for inflammation, whose peripheral immune system is represented in an activated state. We hypothesized that the hyperinflammatory predisposition of Parkinson’s disease patients is pathogenic.

Methods

DBA/1 mice were used to simulate “highly inflammatory individuals”, and the carcinogen DEN was used to induce malignancy. Hematoxylin & eosin (H&E) staining was used to observe the formation of lung tumors. Apoptosis of neurons was observed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Immunohistochemistry and flow cytometry were used to observe CD4, CD28, major histocompatibility complex II (MHCII), cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), and programmed death 1 (PD-1). The ionized calcium binding adaptor molecule-1 (IBA-1) + inducible nitric oxide synthase (iNOS) was used to label M1 microglia, and IBA-1 + arginase 1 (Arg1) was used to label M2 microglia by immunofluorescence. The expression of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and anti-inflammatory cytokines IL-10 and IL-4 was detected by ELISA.

Results

DBA/1 mice with high inflammatory tendency showed a continuous increase of peripheral inflammation, promoting intracranial inflammation, decreasing the tumor incidence and increasing the neurodegeneration under induction of malignant change. CD28 and CTLA-4/PD-1 reduced the T-cell-dominated inflammatory response, reduced the intracerebral inflammatory response, protected from neurodegeneration, and increased the incidence of tumor. Combination of CTLA-4 and PD-1 blocker can overactivate T cells, worsen peripheral and intracranial inflammation, reduce the incidence of tumor, cause damage to dopamine neurons, and promote the occurrence of neurodegeneration.

Conclusion

High inflammatory tendency induced by malignant stimulation through the imbalance of CD28 and CTLA-4/PD-1 leads to dopamine neuron injury.

Polymorphisms of Interleukin-6 and Interleukin-8 Are Not Associated with Parkinson's Disease in Taiwan

Background: Studies have suggested that cytokines are crucial mediators in the pathogenesis of Parkinson’s disease (PD). The multifunctional cytokine interleukin (IL)-6 and its single nucleotide polymorphisms (SNPs) were found to have an impact on the development of PD. However, different studies in associations of IL-6 genetic variants with PD showed inconsistent results and it has never been explored in a Taiwanese population. Both IL-1α and IL-8 contribute to the same inflammation pathway. IL-1α genetic polymorphism has an effect on late-onset PD in Taiwan, whereas the associations of IL-8 genetic variants with PD in Taiwan remain to be investigated. Methods: This study examined the frequencies of polymorphisms within the critical promoter areas of the proinflammatory cytokine genes: IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) in Taiwanese PD patients compared with age-and gender-matched healthy subjects. Comparisons were also made in genotype and allele frequencies of IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) among different populations in previous studies. Results: In total, 1120 subjects, including 509 PD patients (female/male: 259/250) and 511 control subjects (female/male: 252/259), were recruited. We found no statistically significant differences in IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) genotypic and allelic distribution between PD and controls, even after being stratified by age at onset and gender. Conclusions: The results did not demonstrate any association of IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) with PD in a Taiwanese population. Despite the negative results, this is the first study in associations of IL-6 G-174C (rs1800795) and IL-8 A-251T (rs4073) with PD in Taiwan. The relevance of genetic variants of IL-6 G-174C (rs1800795) or IL-8 A-251T (rs4073) on PD susceptibility warrants further investigation.

"Janus-Faced" α-Synuclein: Role in Parkinson's Disease

Parkinson's disease (PD) is a pathological condition characterized by the aggregation and the resultant presence of intraneuronal inclusions termed Lewy bodies (LBs) and Lewy neurites which are mainly composed of fibrillar α-synuclein (α-syn) protein. Pathogenic aggregation of α-syn is identified as the major cause of LBs deposition. Several mutations in α-syn showing varied aggregation kinetics in comparison to the wild type (WT) α-syn are reported in PD (A30P, E46K, H 50Q, G51D, A53E, and A53T). Also, the cell-to-cell spread of pathological α-syn plays a significant role in PD development. Interestingly, it has also been suggested that the pathology of PD may begin in the gastrointestinal tract and spread via the vagus nerve (VN) to brain proposing the gut-brain axis of α-syn pathology in PD. Despite multiple efforts, the behavior and functions of this protein in normal and pathological states (specifically in PD) is far from understood. Furthermore, the etiological factors responsible for triggering aggregation of this protein remain elusive. This review is an attempt to collate and present latest information on α-syn in relation to its structure, biochemistry and biophysics of aggregation in PD. Current advances in therapeutic efforts toward clearing the pathogenic α-syn via autophagy/lysosomal flux are also reviewed and reported.

Mechanistic insights and perspectives involved in neuroprotective action of quercetin

Neurodegenerative diseases (NDDs) are the primary cause of disabilities in the elderly people. Growing evidence indicates that oxidative stress, mitochondrial dysfunction, neuroinflammation and apoptosis are associated with aging and the basis of most neurodegenerative disorders. Quercetin is a flavonoid with significant pharmacological effects and promising therapeutic potential. It is widely distributed among plants and typically found in daily diets mainly in fruits and vegetables. It shows a number of biological properties connected to its antioxidant activity. Neuroprotection by quercetin has been reported in many in vitro as well as in in vivo studies. However, the exact mechanism of action is still mystery and similarly there are a number of hypothesis exploring the mechanism of neuroprotection. Quercetin enhances neuronal longevity and neurogenesis by modulating and inhibiting wide number of pathways. This review assesses the food sources of quercetin, its pharmacokinetic profile, structure activity relationship and its pathophysiological role in various NDDs and it also provides a synopsis of the literature exploring the relationship between quercetin and various downstream signalling pathways modulated by quercetin for neuroprotection for eg. nuclear factor erythroid 2-related factor 2 (Nrf2), Paraoxonase-2 (PON2), c-Jun N-terminal kinase (JNK), Tumour Necrosis Factor alpha (TNF-α), Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha (PGC-1α), Sirtuins, Mitogen-activated protein kinases (MAPKs) signalling cascades, CREB (Cyclic AMP response element binding protein) and Phosphoinositide 3- kinase(PI3K/Akt). Therefore, the aim of the present review was to elaborate on the cellular and molecular mechanisms of the quercetin involved in the protection against NDDs.

The Contribution of Microglia to Neuroinflammation in Parkinson's Disease

With the world's population ageing, the incidence of Parkinson's disease (PD) is on the rise. In recent years, inflammatory processes have emerged as prominent contributors to the pathology of PD. There is great evidence that microglia have a significant neuroprotective role, and that impaired and over activated microglial phenotypes are present in brains of PD patients. Thereby, PD progression is potentially driven by a vicious cycle between dying neurons and microglia through the instigation of oxidative stress, mitophagy and autophagy dysfunctions, a-synuclein accumulation, and pro-inflammatory cytokine release. Hence, investigating the involvement of microglia is of great importance for future research and treatment of PD. The purpose of this review is to highlight recent findings concerning the microglia-neuronal interplay in PD with a focus on human postmortem immunohistochemistry and single-cell studies, their relation to animal and iPSC-derived models, newly emerging technologies, and the resulting potential of new anti-inflammatory therapies for PD.

The CD200R1 microglial inhibitory receptor as a therapeutic target in the MPTP model of Parkinson's disease

Background

It is suggested that neuroinflammation, in which activated microglial cells play a relevant role, contributes to the development of Parkinson’s disease (PD). Consequently, the modulation of microglial activation is a potential therapeutic target to be taken into account to act against the dopaminergic neurodegeneration occurring in this neurological disorder. Several soluble and membrane-associated inhibitory mechanisms contribute to maintaining microglial cells in a quiescent/surveillant phenotype in physiological conditions. However, the presence of activated microglial cells in the brain in PD patients suggests that these mechanisms have been somehow overloaded. We focused our interest on one of the membrane-associated mechanisms, the CD200-CD200R1 ligand-receptor pair.

Methods

The acute MPTP experimental mouse model of PD was used to study the temporal pattern of mRNA expression of CD200 and CD200R1 in the context of MPTP-induced dopaminergic neurodegeneration and neuroinflammation. Dopaminergic damage was assessed by tyrosine hydroxylase (TH) immunoreactivity, and neuroinflammation was evaluated by the mRNA expression of inflammatory markers and IBA1 and GFAP immunohistochemistry. The effect of the modulation of the CD200-CD200R1 system on MPTP-induced damage was determined by using a CD200R1 agonist or CD200 KO mice.

Results

MPTP administration resulted in a progressive decrease in TH-positive fibres in the striatum and TH-positive neurons in the substantia nigra pars compacta, which were accompanied by transient astrogliosis, microgliosis and expression of pro- and anti-inflammatory markers. CD200 mRNA levels rapidly decreased in the ventral midbrain after MPTP treatment, while a transient decrease of CD200R1 mRNA expression was repeatedly observed in this brain area at earlier and later phases. By contrast, a transient increase in CD200R1 expression was observed in striatum. The administration of a CD200R1 agonist resulted in the inhibition of MPTP-induced dopaminergic neurodegeneration, while microglial cells showed signs of earlier activation in CD200-deficient mice.

Conclusions

Collectively, these findings provide evidence for a correlation between CD200-CD200R1 alterations, glial activation and neuronal loss. CD200R1 stimulation reduces MPTP-induced loss of dopaminergic neurons, and CD200 deficiency results in earlier microglial activation, suggesting that the potentiation of CD200R1 signalling is a possible approach to controlling neuroinflammation and neuronal death in PD.

Mechanisms of Neurodegeneration in Various Forms of Parkinsonism-Similarities and Differences

Parkinson's disease (PD), dementia with Lewy body (DLB), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and multiple system atrophy (MSA) belong to a group of neurodegenerative diseases called parkinsonian syndromes. They share several clinical, neuropathological and genetic features. Neurodegenerative diseases are characterized by the progressive dysfunction of specific populations of neurons, determining clinical presentation. Neuronal loss is associated with extra- and intracellular accumulation of misfolded proteins. The parkinsonian diseases affect distinct areas of the brain. PD and MSA belong to a group of synucleinopathies that are characterized by the presence of fibrillary aggregates of α-synuclein protein in the cytoplasm of selected populations of neurons and glial cells. PSP is a tauopathy associated with the pathological aggregation of the microtubule associated tau protein. Although PD is common in the world's aging population and has been extensively studied, the exact mechanisms of the neurodegeneration are still not fully understood. Growing evidence indicates that parkinsonian disorders to some extent share a genetic background, with two key components identified so far: the microtubule associated tau protein gene (MAPT) and the α-synuclein gene (SNCA). The main pathways of parkinsonian neurodegeneration described in the literature are the protein and mitochondrial pathways. The factors that lead to neurodegeneration are primarily environmental toxins, inflammatory factors, oxidative stress and traumatic brain injury.

Helicobacter pylori infection is associated with a poor response to levodopa in patients with Parkinson's disease: a systematic review and meta-analysis

BACKGROUND

Helicobacter pylori (HP) infection has been reported to be associated with increased severity of Parkinson's disease (PD) and have negative effects on drug response in patients. We aimed to investigate the influence of HP infection on patients with PD using a systematic review and meta-analysis approach.

METHODS

PubMed and EMBASE databases for relevant articles published before October 2020 were searched. Two authors independently screened records, extracted data, and evaluated the quality of the included studies. The odds ratios (ORs) or standardized mean differences (SMDs) with their corresponding 95% confidence intervals (CIs) were used to calculate the pooled results by employing a random or fixed-effects model. Sensitivity analyses were conducted, and potential publication bias was assessed.

RESULTS

A total of 13 studies were included in our meta-analysis. Overall, PD patients with HP infection had significantly higher levodopa equivalent daily dose (UPDRS) motor scores (SMD = 0.266; 95% CI 0.065-0.467; P = 0.009) and more units of levodopa equivalent daily dose (LEDD) (SMD = 0.178; 95% CI 0.004-0.353; P = 0.046) than those of patients without HP infection. Additionally, the time to achieve 'ON' state was significantly longer (SMD = 0.778; 95% CI 0.337-1.220; P = 0.001) and the duration of 'ON' state was significantly shorter (SMD = -0.539; 95% CI = -0.801 to  -0.227; P = 0.001) in patients with HP infection than in those without HP infection.

CONCLUSION

Our pooled results of this meta-analysis demonstrated that HP infection was associated with worse motor symptoms, higher LEDD, and worse response to drugs in patients with PD. This evidence emphasizes the importance of considering subsequent eradication of HP infection in patients with PD.

Early low-dose ghrelin intervention via miniosmotic pumps could protect against the progressive dopaminergic neuron loss in Parkinson's disease mice

Ghrelin has been identified as a multifunctional peptide that has a potential application for treating Parkinson's disease (PD). The objective of this study was to assess the effects of subcutaneous administration of low-dose ghrelin via miniosmotic pumps on PD progression. The decreased levels of total and active ghrelin in plasma were rescued by ghrelin administration in PD mice. Interestingly, ghrelin did not affect weight gain in wild-type mice but improved weight loss in PD mice. We observed the attenuation of dopaminergic neuron loss in substantia nigra and a low level of dopamine content in the striatum in PD mice with ghrelin treatment. Ghrelin administration could improve the microenvironment of dopaminergic neurons by inhibiting microglial proliferation and proinflammatory cytokine expression and could enhance cell survival by upregulating Bcl-2/Bax ratio and superoxide dismutase1 protein level in the substantia nigra of PD mice. Subcutaneous administration of low-dose ghrelin could prevent the onset of the progression of PD and also provide a possible method for ghrelin application to cure PD.

Glial activation precedes alpha-synuclein pathology in a mouse model of Parkinson's disease

Neuroinflammation is increasingly recognized as an important feature in the pathogenesis of Parkinson's disease (PD). However, it remains unclear whether neuroinflammation contributes to nigral degeneration in PD or is merely a secondary marker of neurodegeneration. We aimed to investigate the temporal relationship between synucleopathy, neuroinflammation and nigrostriatal degeneration in a mouse model of PD. Mice received unilateral intrastriatal injection of alpha-synuclein pre-formed fibrils, alpha-synuclein monomer or vehicle and were sacrificed at 15, 30 and 90 days post-injection. Intrastriatal inoculation of alpha-synuclein fibrils led to significant alpha-synuclein aggregation in the substantia nigra peaking at 30 days after injection while the significant increase in Iba-1 cells, GFAP cells and IL-1β expression peaked earlier at 15 days. At 90 days, the striatal dopaminergic denervation was associated with astroglial activation. Alpha-synuclein monomer did not result in long-term glia activation or increase in inflammatory markers. The spread of alpha-synuclein aggregates into the cortex was not associated with any changes to neuroinflammatory markers. Our results demonstrate that in the substantia nigra glial activation is an early event that precedes alpha-synuclein inclusion formation, suggesting neuroinflammation could play an important early role in the pathogenesis of PD.

Extra-Gastric Manifestations of Helicobacter pylori Infection

Helicobacter Pylori (H. pylori) is a Gram-negative flagellated microorganism that has been extensively studied since its first isolation due to its widespread diffusion and association with numerous diseases. While the bacterium is proved to be a causative factor for a number of gastric diseases such as gastritis, gastric adenocarcinoma, and MALT-lymphoma, its role at other gastrointestinal levels and in other systems is being thoroughly studied. In this article, we reviewed the latest published clinical and laboratory studies that investigated associations of H. pylori with hematologic diseases such as Vitamin B12- and iron-deficiency anemia, primary immune thrombocytopenia, and with a number of dermatologic and ophthalmic diseases. In addition, the putative role of the bacterium in inflammatory bowel diseases, esophageal disorders, metabolic, diseases, neurologic diseases and allergy were outlined.