Inhibitory Effects of Vernonia amygdalina Leaf Extracts on Free Radical Scavenging, Tyrosinase, and Amylase Activities.

Cytotoxicity and instability are the limitations when using bioactive compounds in cosmetic and pharmacology products. This study assesses Vernonia amygdalina leaf extracts for their antityrosinase, antiamylase, and antioxidant activities. Group A extracts were obtained using an aqueous solvent system [70% (v/v) of methanol (BTL70ME), ethanol (BTL70ET), and acetone (BTL70AC)]. Group B extracts were obtained using organic solvents of varying polarities. The results displayed that all extracts exhibited antityrosinase, antiamylase, and antioxidant activities in vitro. The most potent antityrosinase activity was observed in BTL70AC, with a half-maximal inhibitory concentration (IC50) value of 20 µg/mL. BTL_Ethyl acetate and BTL70AC showed potential antiamylase activity. BTL_Isopropanol and BTL_Ethanol exhibited potential antioxidant activity, with IC50 values of 4.0 µg/mL. The total phenolic content of BTL70ME, BTL70ET, and BTL70AC was 72.29±14.14, 65.98±11.91, and 69.37±7.72 mg gallic acid/g extract, respectively. The total flavonoid content was 53.04±5.22, 44.35±13.17, and 61.74±13.17 mg quercetin/g extract, respectively. Group A extracts contained polyphenols, flavonoids, saponins, terpenoids, steroids, and cardiac glycosides. These biological properties can potentially be attributed to the types and quantities of phytochemicals present. Bioactive compounds in the extracts may exert synergistic effects in vitro by interfering with the conformational changes of tyrosinase during substrate binding. Both groups of extracts have the potential to suppress biomolecule degradation, promote antiaging and antimelasma effects, and their phytochemicals can help lower blood glucose levels in diabetes.

Physiological Effects of Neonicotinoid Insecticides on Non-Target Aquatic Animals-An Updated Review.

In this paper, we review the effects of large-scale neonicotinoid contaminations in the aquatic environment on non-target aquatic invertebrate and vertebrate species. These aquatic species are the fauna widely exposed to environmental changes and chemical accumulation in bodies of water. Neonicotinoids are insecticides that target the nicotinic type acetylcholine receptors (nAChRs) in the central nervous systems (CNS) and are considered selective neurotoxins for insects. However, studies on their physiologic impacts and interactions with non-target species are limited. In researches dedicated to exploring physiologic and toxic outcomes of neonicotinoids, studies relating to the effects on vertebrate species represent a minority case compared to invertebrate species. For aquatic species, the known effects of neonicotinoids are described in the level of organismal, behavioral, genetic and physiologic toxicities. Toxicological studies were reported based on the environment of bodies of water, temperature, salinity and several other factors. There exists a knowledge gap on the relationship between toxicity outcomes to regulatory risk valuation. It has been a general observation among studies that neonicotinoid insecticides demonstrate significant toxicity to an extensive variety of invertebrates. Comprehensive analysis of data points to a generalization that field-realistic and laboratory exposures could result in different or non-comparable results in some cases. Aquatic invertebrates perform important roles in balancing a healthy ecosystem, thus rapid screening strategies are necessary to verify physiologic and toxicological impacts. So far, much of the studies describing field tests on non-target species are inadequate and in many cases, obsolete. Considering the current literature, this review addresses important information gaps relating to the impacts of neonicotinoids on the environment and spring forward policies, avoiding adverse biological and ecological effects on a range of non-target aquatic species which might further impair the whole of the aquatic ecological web.

Co-Treatment of Copper Oxide Nanoparticle and Carbofuran Enhances Cardiotoxicity in Zebrafish Embryos.

The use of chemicals to boost food production increases as human consumption also increases. The insectidal, nematicidal and acaricidal chemical carbofuran (CAF), is among the highly toxic carbamate pesticide used today. Alongside, copper oxide nanoparticles (CuO) are also used as pesticides due to their broad-spectrum antimicrobial activity. The overuse of these pesticides may lead to leaching into the aquatic environments and could potentially cause adverse effects to aquatic animals. The aim of this study is to assess the effects of carbofuran and copper oxide nanoparticles into the cardiovascular system of zebrafish and unveil the mechanism behind them. We found that a combination of copper oxide nanoparticle and carbofuran increases cardiac edema in zebrafish larvae and disturbs cardiac rhythm of zebrafish. Furthermore, molecular docking data show that carbofuran inhibits acetylcholinesterase (AChE) activity in silico, thus leading to impair cardiac rhythms. Overall, our data suggest that copper oxide nanoparticle and carbofuran combinations work synergistically to enhance toxicity on the cardiovascular performance of zebrafish larvae.

Antidepressant Screening Demonstrated Non-Monotonic Responses to Amitriptyline, Amoxapine and Sertraline in Locomotor Activity Assay in Larval Zebrafish.

Antidepressants are well-known drugs to treat depression and major depressive disorder for humans. However, the misuse and abuse of antidepressants keep increasing with several side effects reported. The aim of this study was to assess the potential adverse effects of 18 antidepressants by monitoring zebrafish larval locomotor activity performance based on the total distance traveled, burst movement count, and total rotation count at four dark-light intercalated phases. In general, zebrafish larvae displayed sedative effects after antidepressant exposure by showing a significant reduction in all of the locomotor activity-related endpoints. However, three antidepressants i.e., amitriptyline, amoxapine, and sertraline were able to trigger a significantly high locomotor activity in zebrafish larvae during the light cycle. These differences might be due to the pharmacologic differences among the antidepressants. In addition, since each antidepressant possesses a different dosage range from the other, overdoses of these antidepressants might also be the causes of these differences. Furthermore, based on these results, a further study was conducted to observe the effect of these three antidepressants in lower concentrations. From the results, biphasic effects in terms of zebrafish larval locomotor activity were demonstrated by these drugs. Even though further studies are still required to validate the mechanism, these findings indicate that these antidepressants might share a common mechanism responsible for their effects on zebrafish larval locomotor activity although there were some differences in potency of these effects.

Multiple Screening of Pesticides Toxicity in Zebrafish and Daphnia Based on Locomotor Activity Alterations.

Pesticides are widely used to eradicate insects, weed species, and fungi in agriculture. The half-lives of some pesticides are relatively long and may have the dire potential to induce adverse effects when released into the soil, terrestrial and aquatic systems. To assess the potential adverse effects of pesticide pollution in the aquatic environment, zebrafish (Danio rerio) and Daphnia magna are two excellent animal models because of their transparent bodies, relatively short development processes, and well-established genetic information. Moreover, they are also suitable for performing high-throughput toxicity assays. In this study, we used both zebrafish larvae and water flea daphnia neonates as a model system to explore and compare the potential toxicity by monitoring locomotor activity. Tested animals were exposed to 12 various types of pesticides (three fungicides and 9 insecticides) for 24 h and their corresponding locomotor activities, in terms of distance traveled, burst movement, and rotation were quantified. By adapting principal component analysis (PCA) and hierarchical clustering analysis, we were able to minimize data complexity and compare pesticide toxicity based on locomotor activity for zebrafish and daphnia. Results showed distinct locomotor activity alteration patterns between zebrafish and daphnia towards pesticide exposure. The majority of pesticides tested in this study induced locomotor hypo-activity in daphnia neonates but triggered locomotor hyper-activity in zebrafish larvae. According to our PCA and clustering results, the toxicity for 12 pesticides was grouped into two major groups based on all locomotor activity endpoints collected from both zebrafish and daphnia. In conclusion, all pesticides resulted in swimming alterations in both animal models by either producing hypo-activity, hyperactivity, or other changes in swimming patterns. In addition, zebrafish and daphnia displayed distinct sensitivity and response against different pesticides, and the combinational analysis approach by using a phenomic approach to combine data collected from zebrafish and daphnia provided better resolution for toxicological assessment.

Review of Copper and Copper Nanoparticle Toxicity in Fish.

This review summarizes the present knowledge on the toxicity of copper and copper nanoparticles (CuNPs) to various fish species. In previous decades, the excessive usage of metal and metallic nanoparticles has increased significantly, increasing the probability of the accumulation and discharge of metals in various trophic levels of the environment. Due to these concerns, it is important to understand the toxicity mechanisms of metals and metallic nanoparticles before they lead to unhealthy effects on human health. In this review paper, we specifically focus on the effect of metal copper and CuNPs on different fish organs under different physiochemical parameters of various water bodies. Nowadays, different forms of copper have distinctive and specific usages, e.g., copper sulfate is a well-established pesticide which is used to control the growth of algae in lakes and ponds. Deactivating the fungi enzymes prevents fungal spores from germinating. This process of deactivation is achieved via the free cupric ions, which are established as the most toxic forms of copper. Complexes of copper with other ligands may or may not be bioavailable for use in aquatic organisms. On the other hand, CuNPs have shown cost-effectiveness and numerous promising uses, but the toxicity and availability of copper in a nanoparticle form is largely unknown, Additionally, physiochemical factors such as the hardness of the water, alkalinity, presence of inorganic and organic ligands, levels of pH, and temperature in various different water bodies affect the toxicity caused by copper and CuNPs. However, comprehensive knowledge and data regarding the pattern of toxicity for copper metal ions and CuNPs in marine organisms is still limited. In this review, we carry out a critical analysis of the availability of the toxicological profiles of copper metal ions and CuNPs for different fishes in order to understand the toxicity mechanisms of copper and CuNPs. We believe that this review will provide valuable information on the toxicological profile of copper, which will further help in devising safe guidelines for the usage of copper and CuNPs in a sustainable manner.