Effect of cabergoline alginate nanocomposite on the transgenic Drosophila melanogaster model of Parkinson's disease.

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra of the midbrain. Dopamine agonists help the patients with PD by reversing the dopamine depletion and related motor deficits. In the present work, cabergoline, a potent ergot dopamine agonist, was given in the form of cabergoline alginate nanocomposite (CANC) to the PD model flies to study its effects on climbing ability, activity pattern, life span, lipid peroxidation, glutathione (GSH) content, glutathione-S-transferase (GST) activity, dopamine content, protein carbonyl content, mean gray-scale values, and caspase-3 and caspase-9 activities. Cabergoline alginate nanocomposite was synthesized by adding the cabergoline solution in the warm aqueous solution of sodium alginate; The synthesized CANC was characterized using fourier transform (FTIR) infrared spectroscopy, transmission electron microscopy (TEM), and UV-Visible spectroscopic techniques. The synthesized CANC having the final doses of 1, 2, and 3 µM was supplemented with diet and the flies were allowed to feed on it for 24 days. Cabergoline alginate nanocomposite significantly increases climbing ability, reduces lipid peroxidation, GST activity, protein carbonyl content, caspase 3/9 activity, mean gray-scale values, and increases the GSH as well as dopamine content in a dose-dependent manner. The results of this study suggest that CANC is potent in delaying and reducing the symptoms of PD.

Dopamine: Agonists and Neurodegenerative Disorders.

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative disease characterized by the loss of dopaminergic neurons within the substantia nigra pars compacta (SNpc). Despite many researches, there is still no cure for this disease. Levodopa is the first line treatment of PD, but the long term use of it leads to motor impairments and dyskinesias. The dopamine agonists are the preferred choice for the treatment of PD. They are neuroprotective in nature but have side effects. OBJECTIVE: Our aim was to review the work that has been carried out on dopamine agonists and the future possibilities to reduce their side effects. CONCLUSION: In this review, we highlighted the metabolism of dopamine, different types of dopamine agonists with their properties and possible side effects.

Protective effect of capsaicin against methyl methanesulphonate induced toxicity in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg9.

Capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) is the main component in hot peppers, including red chili peppers, jalapenos, and habanero, belonging to the genus Capsicum. Capsaicin is a potent antioxidant that interferes with free radical activities. In the present study, the possible protective effect of capsaicin was studied against methyl methanesulphonate (MMS) induced toxicity in third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg9. The third instar was allowed to feed on the diet having different doses of capsaicin and MMS separately and in combination. The results suggested that the exposure of third instar larvae to the diet having MMS alone showed significant hsp70 expression as well as tissue DNA and oxidative damage, whereas the larvae feed on the diet having MMS and capsaicin showed a decrease in the toxic effects for 48-h of exposure. In conclusion, capsaicin showed a dose-dependent decrease in the toxic effects induced by MMS in the third instar larvae of transgenic Drosophila melanogaster.

Protective effect of tangeritin in transgenic Drosophila model of Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder caused due to the loss of dopaminergic neurons in substantia nigra region of midbrain. The disease is characterized by the accumulation of alpha-synuclein into depositions known as lewy bodies. Till date there is no cure for PD but the limited number of medications may provide temporary relief from the PD symptoms. Flavonoids are a group of polyphenols found in plants. The health benefits of flavonoids have been universally accepted. Tangeritin is a pentamethoxy flavone found in the peels of Mandarin oranges (Citrus reticulata). The present study was conducted to study the effect of tangeritin on the symptoms of PD exhibited by the PD model transgenic flies (Drosophila melanogaster). Tangeritin at a final concentration of 5, 10 and 20 microM was added to the diet and the flies were allowed to feed on it for 24 days. At the same time other set of PD flies were allowed to feed on a diet having 10-3 M of L-Dopa. The effect of tangeritin was studied on the activity pattern, climbing ability, dopamine content, oxidative stress markers (lipid peroxidation, reduced glutathione, glutathione-S-transferase, protein carbonyl content and monoamine oxidase activity) and on the histopathology of the brain of PD model flies. The study showed that the exposure of PD flies to different doses of tangeritin showed a marked delay in the loss of climbing ability and increase in the dopamine content. Tangeritin also showed a reduction in various oxidative stress markers. Hence it is concluded that tangeritin showed a marked reduction in the PD symptoms and thus could be of great importance for further research in treating PD.

Protective Role of Curcumin against N-Nitrosodiethylamine (NDEA)-Induced Toxicity in Rats.

The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.

Protective effect of Geraniol on the transgenic Drosophila model of Parkinson's disease.

The role of Geraniol was studied on the transgenic Drosophila model flies expressing normal human alpha synuclein (h-αS) in the neurons. Geraniol at final concentration of 10, 20 and 40µM were mixed in the diet and the flies were allowed to feed on it for 24 days. The effect of geraniol was studied on the climbing ability, activity pattern, lipid peroxidation, protein carbonyl, glutathione, dopamine content, and glutathione-S-transferase activity in the brains of transgenic Drosophila. The exposure of PD model flies to 10, 20 and 40µM of geraniol results in a significant delay in the loss of climbing ability (p<0.05), improved activity pattern reduced the oxidative stress (p<0.05) in the brains of transgenic Drosophila as compared to unexposed PD model flies. The results suggest that geraniol is potent in reducing the PD symptoms in transgenic Drosophila model of Parkinson's disease.

Effect of bromocriptine alginate nanocomposite (BANC) on a transgenic Drosophila model of Parkinson's disease.

The effect of bromocriptine, a dopamine agonist, administered in the form of bromocriptine alginate nanocomposite (BANC) was studied on Parkinson's disease (PD) model flies. The synthesized BANC was subject to characterization and, at a final concentration of 0.5, 1.0 and 1.5 µM, was mixed in diet. The PD flies were allowed to feed on it for 24 days. A significant dose-dependent delay in the loss of climbing activity and activity pattern was observed in PD flies exposed to 0.5, 1.0 and 1.5 µM BANC. The PD flies exposed to BANC also showed a significant reduction in lipid peroxidation and glutathione-S-transferase activity, and an increase in glutathione content. However, no gross morphological changes were observed in the brains of PD flies compared with controls. The results suggest that BANC is effective in reducing the PD symptoms in these transgenic flies.

Evaluation of the toxic potential of calcium carbide in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9).

In the present study the toxic potential of calcium carbide (CaC2) was studied on the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9). The third instar larvae were exposed to 2, 4, 8, 16 and 32×10(-3)g/ml of CaC2 in diet for 24h. The results reveal that the dose 2×10(-3)g/ml was not toxic but the remaining doses showed a dose dependent significant increase in the hsp70 expression, ß-galactosidase activity, tissue damage, oxidative stress markers (lipid peroxidation and protein carbonyl content), glutathione-S-transferase activity, expression of Caspase 3 and 9, apoptotic index and DNA damage (midgut cells). A significant reduction as compared to control group in total protein, glutathione content and acetylcholinesterase activity was also observed. The Inductively Coupled Plasma Atomic Emission Spectroscopy analysis (ICPAES) reveals the presence of copper, iron, sodium, aluminium, manganese, calcium, nickel and mercury. The toxic effects of CaC2 in the present study may be attributed to the impurities present in it.

Toxic potential of copper-doped ZnO nanoparticles in Drosophila melanogaster (Oregon R).

AIMS: In the present study, copper-doped ZnO nanoparticles (doped ZnO NPs Cu) were synthesized, characterized and evaluated for their possible toxic effects in Drosophila melanogaster (Oregon R). METHODS AND RESULTS: X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectrometry confirm the formation of doped ZnO NPs Cu. Doped ZnO NPs Cu (3%) were mixed in the diet at final concentrations of 1, 2, 4 and 8 µg/µl. The starved male flies were allowed to feed on it for 4 days. After completion of the desired duration, climbing ability, activity pattern, activity of acetylcholinesterase (AChE), glutathione (GSH), glutathione-S-transferase (GST), lipid peroxidation (LPO), total protein content and caspases were studied. SDS-PAGE was also performed for whole fly homogenate of control as well as treated flies. No loss in the climbing and activity pattern was observed at the selected doses of doped ZnO NPs Cu. No significant change in the levels of AChE, GSH, GST, LPO, caspase 9/3 and total protein content was observed. The brain sections showed no gross changes in the structure and SDS-PAGE patterns also revealed no change in the protein expression. CONCLUSIONS: The results suggest that doped ZnO NPs Cu are non-toxic at 1, 2, 4 and 8 µg/µl of concentration in D. melanogaster.

Detection of aneugenicity and clastogenicity in buccal epithelial cells of pan masala and gutkha users by pan-centromeric FISH analysis.

Chewing of betel quid, smoking and alcohol consumption are all associated with higher incidences of oral cancer. Genetic damage can be detected by fluorescent in situ hybridization (FISH) using human centromeric probes. In the present study FISH was performed on buccal epithelial cells of pan masala and gutkha chewers alone with and without additional tobacco smoking and/or alcohol consumption. The study comprised of 1500 male individuals. The present study found the highest frequency of micronuclei without a centromeric region (MN(-)) among gutkha users who also smoked and drank (P < 0.05). A significant increase in cells having micronuclei with a centromeric region (MN(+)) was observed among pan masala users who also smoked (P < 0.05). The study reveals that the clastogenic effects of pan masala/gutkha increase with smoking and alcohol consumption, but aneugenic effects were also observed among the pan masala chewers who smoked.

Effect of Centella asiatica Leaf Extract on the Dietary Supplementation in Transgenic Drosophila Model of Parkinson's Disease.

The role of Centella asiatica L. leaf extract was studied on the transgenic Drosophila model flies expressing normal human alpha synuclein (h-αS) in the neurons. The leaf extract was prepared in acetone and was subjected to GC-MS analysis. C. asiatica extract at final concentration of 0.25, 0.50, and 1.0 µL/mL was mixed with the diet and the flies were allowed feeding on it for 24 days. The effect of extract was studied on the climbing ability, activity pattern, lipid peroxidation, protein carbonyl content, glutathione content, and glutathione-S-transferase activity in the brains of transgenic Drosophila. The exposure of extract to PD model flies results in a significant delay in the loss of climbing ability and activity pattern and reduced the oxidative stress (P < 0.05) in the brains of PD flies as compared to untreated PD flies. The results suggest that C. asiatica leaf extract is potent in reducing the PD symptoms in transgenic Drosophila model of Parkinson's disease.

Toxic potential of synthesized graphene zinc oxide nanocomposite in the third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg9.

In the present study the graphene zinc oxide nanocomposite (GZNC) was synthesized, characterized, and evaluated for its toxic potential on third instar larvae of transgenic Drosophila melanogaster (hsp70-lacZ)Bg(9). The synthesized GZNC was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The GZNC in 0.1% dimethyl sulphoxide (DMSO) was sonicated for 10 minutes and the final concentrations 0.033, 0.099, 0.199, and 3.996 µg/µL of diet were established. The third instar larvae were allowed to feed on it separately for 24 and 48 hr. The hsp70 expression was measured by o-nitrophenyl-ß-D-galactopyranoside assay, tissue damage was measured by trypan blue exclusion test, and ß-galactosidase activity was monitored by in situ histochemical ß-galactosidase staining. Oxidative stress was monitored by performing lipid peroxidation assay and total protein estimation. Ethidium bromide/acridine orange staining was performed on midgut cells for apoptotic index and the comet assay was performed for the DNA damage. The results of the present study showed that the exposure of 0.199 and 3.996 µg/µL of GZNC was toxic for both 24 hr and 48 hr of exposure. The doses of 0.033 µg/µL and 0.099 of GZNC showed no toxic effects on its exposure to the third instar larvae for 24 hr as well as 48 hr of duration.