Onset and mortality of Parkinson's disease in relation to type II diabetes

Impact of diabetes mellitus type two on incidence and progression of Parkinson's disease: a systematic review of longitudinal patient cohorts

Parkinson's disease (PD) is a chronic neurodegenerative disease of the elderly. Patients suffer from progressive motor and non-motor symptoms. Further, PD patients often present geriatric features like multimorbidity and polypharmacotherapy. A frequent comorbidity of PD patients is diabetes mellitus type two (T2DM). In the last decade growing evidence emerged on the impact of T2DM on PD. Of the present review was to analyze the impact of T2DM on PD incidence and progression in patient cohorts. A systematic review of the literature was performed via PubMed and Google Scholar. Studies on longitudinal PD patient cohorts with at least 10 patients per group were included. The diabetic state of the patient had to be determined. In total, 15 studies were analyzed for this review. According to most of the included studies T2DM increases the risk of developing PD significantly. Disease progression is augmented by T2DM both for motor and cognitive impairments. Some studies also point out a correlation of motor worsening and diabetic status measured by the serum HbA1c level. In relation to biomarkers, PD patients with diabetes have higher neurofilament light chain and Tau level but lower Amyloid beta level. T2DM seems to be a risk factor for the development and progression of PD. PD patients should be screened for T2DM and treatment should be initiated promptly. There is still a lack of knowledge about the molecular mechanisms leading to interactions of these diseases.

Adrenergic blockers, statins, and non-steroidal anti-inflammatory drugs are associated with later age at onset in Parkinson's disease

BACKGROUND

Several factors have been shown to modify the risk of developing Parkinson's disease (PD), including commonly prescribed medications. However, there is little data describing their correlation with age at onset (AAO) of clinical symptoms. The objective of this study was to evaluate the association of treatment with anti-hypertensives, non-steroidal anti-inflammatories (NSAIDs), statins, as well as smoking and family history of PD with AAO in a large clinical cohort.

METHODS

A retrospective review of 1201 initial encounters collected information on known risk-modulating factors for PD, including smoking status and family history, anti-hypertensives, statins, NSAIDs, anti-diabetic medications, and beta-agonists. In addition to general exposure, we determined whether medications of interest were started before or after onset of symptoms. Mean AAO was calculated for each set of variables. T-test and multiple regression analyses were used to evaluate association with AAO.

RESULTS

Exposure to all studied medications showed a strong correlation with older PD AAO, except for smoking and family history, which correlated with younger AAO. Multiple regression analysis identified exposure to adrenergic blockers (AB) (β = 5.7), statins (β = 5.6), and NSAIDs (β = 4.1) as the strongest independent predictors of older PD AAO (p < 0.001). Patients who were started on AB prior to onset of PD symptoms showed the largest average delay of PD AAO (at 72.3 ± 10.1 years), almost 10 years later as compared with those not on AB (62.7 ± 10.7 years) or those who started taking AB after onset of symptoms (63.0 ± 10.6 years).

CONCLUSIONS

Multiple common medications are associated with a considerable delay of PD onset.

Parkinson's disease and glucose metabolism impairment

Parkinson's disease (PD) is the second most common neurodegenerative disorder. PD patients exhibit varying degrees of abnormal glucose metabolism throughout disease stages. Abnormal glucose metabolism is closely linked to the PD pathogenesis and progression. Key glucose metabolism processes involved in PD include glucose transport, glycolysis, the tricarboxylic acid cycle, oxidative phosphorylation, the pentose phosphate pathway, and gluconeogenesis. Recent studies suggest that glucose metabolism is a potential therapeutic target for PD. In this review, we explore the connection between PD and abnormal glucose metabolism, focusing on the underlying pathophysiological mechanisms. We also summarize potential therapeutic drugs related to glucose metabolism based on results from current cellular and animal model studies.

Exploring the therapeutic potential of Chinese herbs on comorbid type 2 diabetes mellitus and Parkinson's disease: A mechanistic study

ETHNOPHARMACOLOGICAL RELEVANCE

Type 2 diabetes mellitus (T2DM) and Parkinson's disease (PD) are chronic conditions that affect the aging population, with increasing prevalence globally. The rising prevalence of comorbidity between these conditions, driven by demographic shifts, severely impacts the quality of life of patients, posing a significant burden on healthcare resources. Chinese herbal medicine has been used to treat T2DM and PD for millennia. Pharmacological studies have demonstrated that medicinal herbs effectively lower blood glucose levels and exert neuroprotective effects, suggesting their potential as adjunctive therapy for concurrent management of T2DM and PD.

AIM OF THE STUDY

To elucidate the shared mechanisms underlying T2DM and PD, particularly focusing on the potential mechanisms by which medicinal herbs (including herbal formulas, single herbs, and active compounds) may treat these diseases, to provide valuable insights for developing therapeutics targeting comorbid T2DM and PD.

MATERIALS AND METHODS

Studies exploring the mechanisms underlying T2DM and PD, as well as the treatment of these conditions with medicinal herbs, were extracted from several electronic databases, including PubMed, Web of Science, Google Scholar, and China National Knowledge Infrastructure (CNKI).

RESULTS

Numerous studies have shown that inflammation, oxidative stress, insulin resistance, impaired autophagy, gut microbiota dysbiosis, and ferroptosis are shared mechanisms underlying T2DM and PD mediated through the NLRP3 inflammasome, NF-κB, MAPK, Keap1/Nrf2/ARE, PI3K/AKT, AMPK/SIRT1, and System XC--GSH-GPX4 signaling pathways. Thirty-four medicinal herbs, including 2 herbal formulas, 4 single herbs, and 28 active compounds, have been reported to potentially exert anti-T2DM and anti-PD effects by targeting these shared mechanisms.

CONCLUSIONS

Traditional Chinese medicine effectively combats T2DM and PD through shared pathological mechanisms, highlighting their potential for application in treating these comorbid conditions.

Dihydromyricetin Improves High Glucose-Induced Dopaminergic Neuronal Damage by Activating AMPK-Autophagy Signaling Pathway

INTRODUCTION

In recent years, a growing number of clinical and biological studies have shown that patients with type 2 diabetes mellitus (T2DM) are at increased risk of developing Parkinson's disease (PD). Prolonged exposure to hyperglycemia results in abnormal glucose metabolism, which in turn causes pathological changes similar to PD, leading to selective loss of dopaminergic neurons in the compact part of the substantia nigra. Dihydromyricetin (DHM) is a naturally occurring flavonoid with various biological activities including antioxidant and hepatoprotective properties. In this study, the effect of DHM on high glucose-induced dopaminergic neuronal damage was investigated.

METHODS

The potential modulatory effects of DHM on high glucose-induced dopaminergic neuronal damage and its mechanism were studied.

RESULTS

DHM ameliorated high glucose-induced dopaminergic neuronal damage and autophagy injury. Inhibition of autophagy by 3-methyladenine abrogated the beneficial effects of DHM on high glucose-induced dopaminergic neuronal damage. In addition, DHM increased levels of p-AMP-activated protein kinase (AMPK) and phosphorylated UNC51-like kinase 1. The AMPK inhibitor compound C eliminated DHM-induced autophagy and subsequently inhibited the ameliorative effects of DHM on high glucose-induced dopaminergic neuronal damage.

DISCUSSION

DHM ameliorates high glucose-induced dopaminergic neuronal damage by activating the AMPK-autophagy pathway.

Trends in parkinson's disease mortality in China from 2004 to 2021: a joinpoint analysis

BACKGROUND

This study aimed to analyze the trends of Parkinson's disease (PD) mortality rates among Chinese residents from 2004 to 2021, provide evidence for the formulation of PD prevention and control strategies to improve the quality of life among PD residents.

METHODS

Demographic and sociological data such as gender, urban or rural residency and age were obtained from the National Cause of Death Surveillance Dataset from 2004 to 2021. We then analyzed the trends of PD mortality rates by Joinpoint regression.

RESULTS

The PD mortality and standardized mortality rates in China showed an overall increasing trend during 2004-2021 (average annual percentage change [AAPC] = 7.14%, AAPCASMR=3.21%, P < 0.001). The mortality and standardized mortality rate in male (AAPC = 7.65%, AAPCASMR=3.18%, P < 0.001) were higher than that of female (AAPC = 7.03%, AAPCASMR=3.09%, P < 0.001). The PD standardized mortality rates of urban (AAPC = 5.13%, AAPCASMR=1.76%, P < 0.001) and rural (AAPC = 8.40%, AAPCASMR=4.29%, P < 0.001) residents both increased gradually. In the age analysis, the mortality rate increased with age. And the mortality rates of those aged > 85 years was the highest. Considering gender, female aged > 85 years had the fastest mortality trend (annual percentage change [APC] = 5.69%, P < 0.001). Considering urban/rural, rural aged 80-84 years had the fastest mortality trend (APC = 6.68%, P < 0.001).

CONCLUSIONS

The mortality rate of PD among Chinese residents increased from 2004 to 2021. Male sex, urban residence and age > 85 years were risk factors for PD-related death and should be the primary focus for PD prevention.

The Contribution of Type 2 Diabetes to Parkinson's Disease Aetiology

Type 2 diabetes (T2D) and Parkinson's disease (PD) are chronic disorders that have a significant health impact on a global scale. Epidemiological, preclinical, and clinical research underpins the assumption that insulin resistance and chronic inflammation contribute to the overlapping aetiologies of T2D and PD. This narrative review summarises the recent evidence on the contribution of T2D to the initiation and progression of PD brain pathology. It also briefly discusses the rationale and potential of alternative pharmacological interventions for PD treatment.

Diabetes: a tipping point in neurodegenerative diseases

Diabetes is associated with an increased risk and progression of Alzheimer's (AD) and Parkinson's (PD) diseases. Conversely, diabetes may confer neuroprotection against amyotrophic lateral sclerosis (ALS). It has been posited that perturbations in glucose and insulin regulation, cholesterol metabolism, and mitochondrial bioenergetics defects may underlie the molecular underpinnings of diabetes effects on the brain. Nevertheless, the precise molecular mechanisms remain elusive. Here, we discuss the evidence from molecular, epidemiological, and clinical studies investigating the impact of diabetes on neurodegeneration and highlight shared dysregulated pathways between these complex comorbidities. We also discuss promising antidiabetic drugs, molecular diagnostics currently in clinical trials, and outstanding questions and challenges for future pursuit.