Diabetes Mellitus and Parkinson's Disease: Shared Pathophysiological Links and Possible Therapeutic Implications.

Abdallah Hassan,Jeevan Gautam,Rohi Mishra,Nusrat Jahan,Rajan Sharma Kandel,Amer Alaref

doi:10.7759/cureus.9853

Abstract

Diabetes mellitus (DM) is the most common chronic metabolic disease. Parkinson's disease (PD) is considered one of the most common neurodegenerative diseases. There are many similarities between both conditions. Both disorders are chronic diseases. Both diseases result from a decrease in a specific substance: dopamine in PD, and insulin in DM. Besides, both disorders arise due to the destruction of particular cells, dopaminergic cells in PD, and pancreatic beta-cell in DM. Recently, many epidemiological and experimental studies showed a connection between DM and PD. There are common underlying mechanisms in the pathophysiology of both diseases. These underlying mechanisms include mitochondrial dysfunction, oxidative stress, hyperglycemia, and inflammation. Insulin resistance is indeed the hallmark of DM, especially type 2 diabetes mellitus (T2DM), which plays a significant role in these pathophysiological and molecular mechanisms. Besides, many studies revealed that anti-diabetic drugs have a beneficial effect on PD.In this current literature review, we aim to explore the standard pathophysiological and molecular linkages between these two disorders as well as how DM could affect the incidence and progression of PD. We also review how anti-diabetic drugs impact PD. In the future, further experimental and expanded clinical studies are needed to fully understand the exact pathophysiological connections between the two disorders and the efficacy of insulin and other anti-diabetic drugs in the treatment of PD in diabetic patients. Fully understanding and targeting these pathophysiological and molecular links could result in de novo curative therapy for PD and DM.

Highlights

BackgroundParkinson's disease (PD) is a chronic, gradually progressive neurodegenerative disease
We found out how Diabetes mellitus (DM) increases the risk of PD
We have found that many studies revealed that DM increases the risk of PD

Summary

Introduction

Parkinson's disease (PD) is a chronic, gradually progressive neurodegenerative disease. In 1917, James Parkinson wrote the first clear medical description of the PD. 1% of people aged over 65 years are affected, which increases to 4-5% among people above 85 years [1]. PD is known to have both motor and non-motor clinical signs. Non-motor symptoms include dementia, depression, social phobia, anxiety, loss of smell, fear, and autonomic symptoms [3]. The motor symptoms are related to the destruction of the pigmented neuronal cells in the substantia nigra (SN) in the brain; these are dopamine secreting cells. Dopamine is a major neurotransmitter that plays an essential role in transmitting the motor signals from the brain to the motor center. Dopamine decreases in PD, which leads to the different symptoms of the PD [2]

Objectives

Results

Discussion

Conclusion