Folic acid supplementation rescues anomalies associated with knockdown of parkin in dopaminergic and serotonergic neurons in Drosophila model of Parkinson's disease.

parkin loss associated early-onset of Parkinson's disease, involves mitochondrial dysfunction and oxidative stress as the plausible decisive molecular mechanisms in disease pathogenesis. Mitochondrial dysfunction involves several up/down regulation of gene products, one of which being p53 is found to be elevated. Elevated p53 is involved in mitochondrial mediated apoptosis of neuronal cells in Parkinson's patients who are folate deficient as well. The present study therefore attempts to examine the effect of Folic acid (FA) supplementation in alleviation of anomalies associated with parkin knockdown using RNAi approach, specific to Dopaminergic (DA) neurons in Drosophila model system. Here we show that FA supplementation provide protection against parkin RNAi associated discrepancies, thereby improves locomotor ability, reduces mortality and oxidative stress, and partially improves Zn levels. Further, metabolic active cell status and ATP levels were also found to be improved thereby indicating improved mitochondrial function. To corroborate FA supplementation in mitochondrial functioning further, status of p53 and spargel was checked by qRT-PCR. Here we show that folic acid supplementation enrich mitochondrial functioning as depicted from improved spargel level and lowered p53 level, which was originally vice versa in parkin knockdown flies cultured in standard media. Our data thus support the potential of folic acid in alleviating the behavioural defects, oxidative stress, augmentation of zinc and ATP levels in parkin knock down flies. Further, folic acid role in repressing mitochondrial dysfunction is encouraging to further explore its possible mechanistic role to be utilized as potential therapeutics for Parkinson's disease.

Folic Acid Supplementation Ameliorates Oxidative Stress, Metabolic Functions and Developmental Anomalies in a Novel Fly Model of Parkinson's Disease.

Mutations in parkin cause early-onset Parkinson's disease. Studies involving Drosophila model have emphasised mitochondrial dysfunction as a critical event in disease pathogenesis. In this context, we employed a novel recessive allele of parkin, park (c00062) , for the current study. The piggyBac insertion at 3rd intron of parkin in park (c00062) was confirmed by PCR. Homozygous park (c00062) has diminished levels of truncated parkin transcript with no detectable protein as confirmed by qRT-PCR and western blot analysis, respectively. The homozygous park (c00062) displayed severe developmental anomalies involving reduced body size, ~45 % pupal lethality, high mortality with locomotory defect, elevated oxidative stress, low metabolic active cell status with low mitochondrial respiration as reflected from reduced ATP levels. Further, folic acid therapeutic potential was analysed in park (c00062) . Here we show that dietary folic acid provided protection against disparities involving pupal lethality, high mortality, locomotory defect, elevated oxidative stress and low metabolic active cell status associated with park (c00062) . Further mitochondrial respiration was enhanced as reflected from improved ATP levels in folate supplemented park (c00062) . To corroborate mitochondrial functioning further our analysis regarding transcript status of p53 and spargel by qRT-PCR, revealed down regulation of p53 and up regulation of spargel in folate supplemented park (c00062) , which was originally vice a versa. Our data thus support the potential of FA in alleviating the disparities associated with parkin loss of function in fly model. Further, FA role in alleviating mitochondrial dysfunction is encouraging to further explore FA mechanistic role to be utilized as potential therapeutics for parkin mediated neurodegenerative diseases.

scribble (scrib) knockdown induces tumorigenesis by modulating Drp1-Parkin mediated mitochondrial dynamics in the wing imaginal tissues of Drosophila.

scrib loss of function is associated with various human-cancers. Most of the human-cancers have been characterized by mitochondrial dysfunction with elevated oxidative stress. However, the role of scrib to mitochondrial dysfunction in cancer has not been investigated earlier. Here, we have shown that scrib knockdown leads to mitochondrial depolarization, fragmentation and perinuclear-clustering along with disruption of the redox homeostasis. Moreover, the scrib abrogated tumor showed the elevation of Drp-1 and reduced expression of Marf, which suggests enhanced mitochondrial-fission. Further, the reduced expression of Parkin and HtrA2 interpret defective mitophagy leading to clustering of fragmented mitochondria and apoptotic inhibition in scrib knockdown tumors. Also, Parkin immunostaining depicted its reduced expression and mislocalization in the tumor cells in comparison to wild type. Moreover, the genetic study revealed the epistatic interactions of parkin and scrib. Thus, for the first time our results suggested that scrib loss induced mitochondrial-dysfunction modulates cancer progression by altering the mitochondrial dynamics regulators.

Mechanically magnified chitosan-based hydrogel as tissue adhesive and antimicrobial candidate.

The present article reports the development of chitosan (CS) based hydrogel series by varying the concentration of cross-linking agent i.e. N,N'-methylenebisacrylamide (MBA) (0.8-1.4 wt%) via free-radical polymerization in aqueous medium. SEM image analysis confirmed the presence of porous 3D-network in the hydrogel. Prepared hydrogel series exhibited good tissue adhesive property along with antimicrobial activity against E. coli, K. pneumonia, S. aureus, C. albicans &M. gypseum bacteria with the good MIC (4-20 mm). The adhesive strength of hydrogel was found 14 kPa, which seems to be quite efficient in tissue adhesiveness applications, which was also validated and tested on Drosophila (Oregon-R) tissues, results were promising. Magnified mechanical strength i.e. storage modulus (G') and loss modulus (G″) were found 106 Pa and 104 Pa, respectively, which makes the hydrogel a potential candidate in the biomedical field. Moreover, CS hydrogel showed good swelling ratio in aqueous medium up to 390% at room temperature.

Knockdown of APPL mimics transgenic Aß induced neurodegenerative phenotypes in Drosophila.

A variety of Drosophila mutant lines have been established as potential disease-models to study various disease mechanisms including human neurodegenerative diseases like Alzheimer's disease (AD), Huntington's disease (HD) and Parkinson's disease (PD). The evolutionary conservation of APP (Amyloid Precursor Protein) and APPL (Amyloid Precursor Protein-Like) and the comparable detrimental effects caused by their metabolic products strongly implies the conservation of their normal physiological functions. In view of this milieu, a comparative analysis on the pattern of neurodegenerative phenotypes between Drosophila APPL-RNAi line and transgenic Drosophila line expressing eye tissue specific human Aß (Amyloid beta) was undertaken. Our results clearly show that Drosophila APPL-RNAi largely mimics transgenic Aß in various phenotypes which include eye degeneration, reduced longevity and motor neuron deficit functions, etc. The ultra-structural morphological pattern of eye degeneration was confirmed by scanning electron microscopy. Further, a comparative study on longevity and motor behaviour between Aß expressing and APPL knockdown lines revealed similar kind of behavioural deficit and longevity phenotypes. Therefore, it is suggested that APPL-knockdown approach can be used as an alternative approach to study neurodegenerative diseases in the fly model. To the best of our knowledge this is the first report showing comparable phenotypes between APPL and Aß in AD model of Drosophila.

Cancer Drug Development Using Drosophila as an in vivo Tool: From Bedside to Bench and Back.

The fruit fly Drosophila melanogaster has been used for modeling cancer and as an in vivo tool for the validation and/or development of cancer therapeutics. The impetus for the use of Drosophila in cancer research stems from the high conservation of its signaling pathways, lower genetic redundancy, short life cycle, genetic amenability, and ease of maintenance. Several cell signaling pathways in Drosophila have been used for cancer drug development. The efficacy of combination therapy and uptake/bioavailability of drugs have also been studied. Drosophila has been validated using several FDA-approved drugs, suggesting a potential application of this model in drug repurposing. The model is emerging as a powerful tool for high-throughput screening and should significantly reduce the cost and time associated with drug development. In this review we discuss the applications of Drosophila in cancer drug development. The advantages and limitations of the model are discussed.

Overview of Alzheimer's Disease and Some Therapeutic Approaches Targeting Aß by Using Several Synthetic and Herbal Compounds.

Alzheimer's disease (AD) is a complex age-related neurodegenerative disease. In this review, we carefully detail amyloid-ß metabolism and its role in AD. We also consider the various genetic animal models used to evaluate therapeutics. Finally, we consider the role of synthetic and plant-based compounds in therapeutics.