Parkinson’s disease (PD) is a severely debilitating neurodegenerative disease, affecting the motor system, leading to resting tremor, cogwheel rigidity, bradykinesia, walking and gait difficulties, and postural instability. The severe loss of dopaminergic neurons in the substantia nigra pars compacta causes striatal dopamine deficiency and the presence of Lewy bodies indicates a pathological hallmark of PD. Although the current treatment of PD aims to preserve dopaminergic neurons or to replace dopamine depletion in the brain, it is notable that complete recovery from the disease is yet to be achieved. Given the complexity and multisystem effects of PD, the underlying mechanisms of PD pathogenesis are yet to be elucidated. The advancement of medical technologies has given some insights in understanding the mechanism and potential treatment of PD with a special interest in the role of microRNAs (miRNAs) to unravel the pathophysiology of PD. In PD patients, it was found that striatal brain tissue and dopaminergic neurons from the substantia nigra demonstrated dysregulated miRNAs expression profiles. Hence, dysregulation of miRNAs may contribute to the pathogenesis of PD through modulation of PD-associated gene and protein expression. This review will discuss recent findings on PD-associated miRNAs dysregulation, from the regulation of PD-associated genes, dopaminergic neuron survival, α-synuclein-induced inflammation and circulating miRNAs. The next section of this review also provides an update on the potential uses of miRNAs as diagnostic biomarkers and therapeutic tools for PD.

Background and Objective: Parkinson disease (PD) is one of the commonest neurodegenerative disorders that affects the motor system, and includes cardinal motor symptoms such as resting tremor, cogwheel rigidity, bradykinesia and postural instability. Its prevalence is increasing worldwide due to increase in life span. Although, two centuries since the first description of the disease, no proper cure with regard to treatment strategies and control of symptoms could be reached. One of the major challenges faced by the researchers is to have a suitable research model. Results: Rodents are the most common PD models used but no single model can replicate the true nature of PD. In this review, we aim to discuss another animal model, the zebrafish (Danio rerio) which is gaining popularity. Zebrafish brain has all the major structures found in the mammalian brain, complete with neurotransmitters systems, and possesses a functional blood-brain barrier similar to humans. From the perspective of PD research, the zebrafish possesses the ventral diencephalon which is thought to be homologous to the mammalian substantia nigra. We summarize the various zebrafish models available to study PD, namely chemical-induced and genetic models. Conclusion: The zebrafish can complement to the use of other animal models for the mechanistic study of PD and help in the screening of new potential therapeutic compounds.

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