Understanding Pathophysiology of Sporadic Parkinson\u27s Disease in Drosophila Model: Potential Opportunities and Notable Limitations

Parkinson’s disease (PD) is the second most common neurodegenerative disorder affecting approximately 1% of the population over age 50. PD is widely accepted as a multifactorial disease with both genetic and environmental contributions. Despite extensive research conducted in the area the precise etiological factors responsible remain elusive. In about 95% Parkinsonism is considered to have a sporadic component. There are currently no established curative, preventative, or disease-modifying interventions, stemming from a poor understanding of the molecular mechanisms of pathogenesis. Here lies the importance of animal models. Pharmacological insults cause Parkinsonian like phenotypes in Drosophila, thereby modelling sporadic PD. The pesticides paraquat and rotenone induced oxidative damage causing cluster specific DA neuron loss together with motor deficits. Studies in fly PD model have deciphered that signaling pathways such as phosphatidylinositol 3-kinase (PI3K/Akt and target of rapamycin (TOR), c-Jun N-terminal kinase (JNK) have been defective. Further, these studies have demonstrated that fruit fly can be a potential model to screen chemical compounds for their neuroprotective efficacy

Parkinson’s Disease: Insights from Drosophila Model

Parkinson’s disease (PD) is a medical condition that has been known since ancient times. It is the second most common neurodegenerative disorder affecting approximately 1% of the population over 50 years. It is characterized by both motor and non-motor symptoms. Most of PD cases are sporadic while 5–10% cases are familial. Environment factors such as exposure to pesticides, herbicides and other heavy metals are expected to be the main cause of sporadic form of the disease. Mutation of the susceptible genes such as SNCA, PINK1, PARKIN, DJ1, and others are considered to be the main cause of the familial form of disease. Drosophila offers many advantages for studying human neurodegenerative diseases and their underlying molecular and cellular pathology. Shorter life span; large number of progeny; conserved molecular mechanism(s) among fly, mice and human; availability of many techniques, and tools to manipulate gene expression makes drosophila a potential model system to understand the pathology associated with PD and to unravel underlying molecular mechanism(s) responsible for dopaminergic neurodegeneration in PD—understanding of which will be of potential assistance to develop therapeutic strategies to PD. In the present review, we made an effort to discuss the contribution of fly model to understand pathophysiology of PD, in understanding the biological functions of genes implicated in PD; to understand the gene-environment interaction in PD; and validation of clues that are generated through genome-wide association studies (GWAS) in human through fly; further to screen and develop potential therapeutic molecules for PD. In nutshell, fly has been a great model system which has immensely contributed to the biomedical research relating to understand and addressing the pathology of human neurological diseases in general and PD in particular

Pattern of salivary gland tumors in Manipur, India: A 10 year study

Background: Salivary gland lesions, especially the neoplastic lesions constitute a highly heterogeneous histopathologic group. Several studies have reported a significant difference in the global distribution of salivary gland tumors, but no formal study has been carried out in this part of the globe. Objectives: To document the pattern of various salivary gland tumors in Manipur, a state in North Eastern India. Materials and Methods: This is a 10 years (2002-2011) retrospective study of all salivary gland specimens received at our referral teaching hospital in Manipur, India. All the histopathology slides of salivary gland specimens during the study period were reviewed and clinical details were obtained from the archives. Restaining of slides and fresh sections of tissue blocks were performed whenever required. Data thus collected were analyzed. Results: A total of 104 cases of salivary gland lesions were studied during the study period. Age ranged from 5 years to 78 years with an overall slight female preponderance (M:F = 1:1.08). Parotid (56.65%) was the commonest gland involved followed by submandibular gland (31.73%).Neoplastic lesions comprised of 78 (75%) cases and non-neoplastic lesions constituted 25% (26 cases). Among the neoplastic lesions, benign lesions (53.85%) predominated over malignant lesions (21.15%). Pleomorphic adenoma was the commonest benign neoplastic lesion and mucoepidermoid carcinoma was the commonest malignant tumor. Chronic sialadenitis was the predominant lesion in the non-neoplastic group. Conclusion: The principal site for salivary gland tumors was the parotid gland and pleomorphic adenoma outnumbered all the other tumors. Females are more affected in the malignant group