Hydroxyapatite Nanoparticle (HAp NPs) is similar to the crystal structure of human bone. It has excellent properties such as biocompatibility, osteoconductivity, and biodegradable. Owing to these properties, it has been used in the field of drug delivery, dental applications, and bone tissue engineering. PEG (Polyethylene glycol) is a synthetic biodegradable polymer. It prevents the agglomeration of the nanoparticles, surface oxidation of the particles and thereby making it more biocompatible. Rose Bengal (RB) is a photo sensitiser which has the ability to generate singlet oxygen. In the present study, PEG/HAp nanocomposite has been synthesised and characterised using DLS and Zeta potential, TEM, and FTIR. The safety efficacy of the PEG/HAp nanocomposite was studied in wild type Drosophila larvae and adult flies after oral administration. Larval crawling assay, negative geotaxis assay, survival assay, biochemical assays—SOD activity, DPPH activity and GSH activity were performed. This study showed that the nanocomposite did not affect the development of the larva rather it enhanced the behavioural and antioxidant activity. In the adult flies, the climbing activity and the survivability patterns were greatly improved. Earlier studies with HAp NPs on the Drosophila model did not enhance behavioural and antioxidant activities whilst in the present study, PEG might help in improving these activities due to its non-immunogenic and non-antigenic properties.

Diet and Functional Foods in Treatment and Maintenance Therapy of Colon DisordersDinesh Kumar, Gurmeet Singh, Mankaran Singh, Deepak Sharma, Mahendra Singh Rathore

Acrylamide, a water-soluble vinyl polymer, is a common environmental toxin present in several industrial effluents and most importantly in high-temperature cooked foods like potato chips, meat, cookies, etc. Studies conducted over a decade have revealed acrylamide’s potency in eliciting detrimental effects in different physiological systems. Researchers have also noticed its presence in the biological samples collected from employees working in mining and ore industries and deemed it to be classified as an occupational hazardous chemical. In this case, we have reviewed acrylamide induced neurotoxicity in D. melanogaster model and prospective phytochemicals for its treatment. This study highlights acrylamide’s role in modulating cellular redox chains and divulges the probable mechanism for induced toxicity. The effect of acrylamide on its major target sites like the neuronal synapse and kinesin proteins are explored as the basis for acrylamide induced toxicity. We also focused our study at the cellular level and other model organisms to better understand acrylamide-induced neuronal apoptosis and mitochondrial depolarisation events. Furthermore, the neuroprotective effects of common phytoconstituents like curcumin and thymoquinone against acrylamide-induced neurotoxicity are discussed.

Bisphenol A (BPA) is an endocrine-disrupting chemical used commonly in the manufacture of plastic bottles, beverage cans, consumer products, and medical devices. It has a high risk of disrupting hormone-mediated processes which are critical for the growth and development of an infant. In the present study, the flies are exposed to different concentrations of BPA (0.05 and 0.5 mM), which represented the federally regulated LOAEL (50 mg/kg bw/day) and a higher dose of 1 mM, to study the change in cell death, nuclear instability oxidative stress, and behavioral anomalies leading to complex behavioral disorders like Autism. Effects of BPA doses (0.05, 0.5, 1 mM) were studied and the flies showed deficits in social interaction, locomotion, and enhanced oxidative stress that was found to be deteriorating among the flies. Automated tracking and robust MATLAB analysis of behavioral paradigms like position, movement, velocity, and courtship have given us an insight into a detrimental change in development and behavior when exposed to BPA. The flies were also co-treated with Cerium Oxide nanoparticles (CeO2 NP), well known for its antioxidant properties due to their antioxidant enzyme biomimetic nature, resulted in low oxidative stress, genotoxicity, and an improvement in behavior. In this work, we have tested our hypothesis of oxidative stress and nuclear instability as a potent cause for improper development in Drosophila when exposed to EDCs like BPA which is a potential hazard for both health and environment and might lead to various developmental disorders in children.

Alzheimer’s disease (AD) is one of the most common forms of dementia. Cognitive dysfunction and memory loss are the two main clinical symptoms of AD. Drosophila melanogaster models of AD, which are based on overexpression of human amyloid β (Aβ) or human tau (hTau) protein, have been used to study the mechanism underlying AD and to screen potential therapeutic compounds. Drugs that are currently available for AD provide only symptomatic relief. Huge unmet medical needs exists to slow, stop, or reverse the progression of AD. Thymoquinone (TQ) is an active ingredient isolated from Nigella sativa (NS) and possesses various pharmacological activities, and it is also a potential neuropharmacological agent. The current study was performed to investigate the effect of dietary administration of TQ at concentrations of 12.5 μM and 25 μM for 15 and 30 days on biochemical and behavioral parameters, gene, and protein expression of hTau, using Drosophila models of AD. Transgenic Drosophila models exhibiting pan-neuronal and eye-specific expression of hTau were generated using the GAL4/UAS system. Treatment with TQ at both concentrations resulted in a significant increase in behavioral activity, a significant reduction in the amount of reactive oxygen species (ROS), and restoration of depleted superoxide dismutase (SOD) and acetylcholine esterase (AChE) activities. A significant decrease in gene and protein expression of hTau was also observed at the molecular level for both concentrations of TQ. Therefore, TQ has the potential to be investigated as a potential therapeutic phytochemical for the treatment of AD in future studies. Graphical Abstract Abbreviations AChE: Acetyl choline esterase AChI: Acetylthiocholine iodide AD: Alzheimer’s disease APP: Amyloid precursor protein

Acrylamide, an environmental pollutant, is known to occur in food substances cooked at high temperatures. Studies on various models indicate acrylamide to cause several physiological conditions such as neuro- and reproductive toxicity, and carcinogenesis. In our study, exposure of Drosophila melanogaster (Oregon K strain) to acrylamide via their diet resulted in a concentration and time-dependent mortality, while the surviving flies exhibited significant locomotor deficits, most likely due to oxidative stress-induced neuronal damage. Also, Drosophila embryos exhibited signs of developmental toxicity as evidenced by the alteration in the migration of border cells and cluster cells during the developmental stages, concomitant to modulation in expression of gurken and oskar genes. Curcumin, a known antioxidant has been widely studied for its neuroprotective effects against acrylamide; however; very few studies focus on thymoquinone for its role against food toxicant. Our research focuses on the toxicity elicited by acrylamide and the ability of the antioxidants: thymoquinone, curcumin and combination of thereof, in reversing the same.

Objective: Andrographis paniculata is widely used in Asia for various medicinal purposes. The plant has a major bioactive chemical constituent Andrographolide, which exhibits various essential pharmacological properties. Recently, to enhance immunity against viral fevers especially dengue viral fever during monsoon season, Tamil Nadu state government has advised rural health centres to provide a tea or kashayam made from a mixture containing this plant leaf along with selected plant roots and leaves. However, there is concern among the general public population that this plant extract may have a negative impact on potency. This study is being done to investigate the toxic effects of Andrographis paniculata on fecundity and physiological properties of Drosophila melanogaster. Methods: The flies were treated and mated in pure and mixed form of Andrographis paniculata separately. Results: The results were obtained in the form of egg count, which was compared to control and the conclusion was obtained that Andrographis paniculata might affect the fecundity and at the same time, it was observed that the developmental span from an egg to an adult fly increased upon treatment in successive generations. More importantly, the effect of pure form plant on the fecundity was found to be significant, while that of the mixed form was not. On mating a treated male with an untreated female and an untreated male with a treated female when the treatment is being discontinued, it can be very well seen that there is no effect on the fecundity of the flies. Conclusion: Since the continuity of the treatment played a major role on the effect of fecundity, highlighting the importance of the period of treatment and the exposure time of the compound on the fly system, therefore this research suggests that the conception of tea or kashayam extracted from mixed plant content could not have the same effect as the similar concentration of pure Andrographis paniculata and it does not have any acute effect on the fecundity when being consumed over a short period of time in Drosophila melanogaster model.

Hydroxyapatite (HAp), a compound similar in composition to human hard tissues such as bone and teeth, has widespread applications in bulk as well as nanoparticle form in numerous fields due to excellent biocompatibility and stability. The increased use of this nanoparticle thus warrants the study of its toxic potential in in vivo models. In this study, the toxicity induced by HAp NPs administered via the oral route using Drosophila as an in vivo model was investigated. Biochemical assays such as lipid peroxidation and nitro blue tetrazolium assay did not reveal toxicity at lowest (10 mu g/ml) as well as highest (1000 mu g/ml) doses. The HAp nanoparticle-treated flies and larvae did not exhibit signs of behavioral change as evidenced from the negative geotaxis assay and larvae crawling assay, respectively. Survival assay to assess the chronic toxicity of HAp nanoparticles also did not reveal any signs of toxicity at both lowest and highest doses. This demonstrates that hydroxyapatite nanoparticles do not elicit significant in vivo toxicity. Considering the paucity of studies available to support the non-toxic effect of HAp nanoparticles, further investigations are warranted in Drosophila and other in vivo models. Moreover, such HAp nanoparticles can also serve as reliable carrier for drug delivery system.

Cerium oxide nanoparticles (nCeO(2)) were synthesized via the hydroxide mediated approach using cerium nitrate hexahydrate and sodium hydroxide as precursors. The nanoparticle was characterized using TEM, XRD and FTIR analysis. Its toxicity at 0.1 mM and 1 mM doses was investigated using wild-type third instar larvae and adult male flies (Oregon K strain) exposed to nCeO(2) along with food for one month. Ascorbic acid (17 mM) was used as a positive control. Results from the survival assay revealed that when compared to control, both 0.1 mM and 1 mM doses were non-toxic for a period of one month, after which the 1 mM dose was more toxic than the 0.1 mM dose. Dietary administration of nCeO(2) at both the doses did not cause developmental and behavioral defects. Important biochemical parameters such as ROS generation, superoxide dismutase activity, carbohydrate and protein levels, and acetylcholinesterase activity were not significantly altered at both the doses of the nanoparticle, when compared to control. The mRNA expression of antioxidant enzymes such as catalase and superoxide dismutase also was not significantly altered in the third instar larvae that fed on nanoparticle-containing food. The results from the above studies suggest that nCeO(2) at 0.1 mM and 1 mM doses did not elicit any significant toxicity in third instar larvae and adult flies when administered for a period of one month. This study also suggests that nCeO(2) can be used as a potential anti-oxidant compound and a beneficial drug carrier in Drosophila disease models in future studies.

The use of TiO2 nanoparticles (NPs) in a wide range of products (specially biomedical applications) in day-to-day life and the notable fact that it is photoactive and generates reactive oxygen species (ROS) create curiousness among researchers to study their effects on different biological systems. Heme-enzymes are known to operate redox reactions in living system in tandem with ROS. Horseradish peroxidase (HRP) being a model heme-enzyme from the peroxidase family was systematically studied for enzymatic changes after interaction with TiO2 NPs under physiologically relevant pH and irradiation conditions. This study gives us an extensive idea of the changes in enzyme kinetics, intrinsic fluorescence, interaction efficiency, and stability of the protein–nanoparticle complex formed. The effect of ROS generated by TiO2 NPs under different irradiation conditions was substantially considered as one of the major factors that influenced the enzyme kinetics apart from protein adsorption on the surface of nanoparticles. The impact of excessive use of TiO2 NPs on the activity of HRP can be discerned from the current study.