Human Hazard Assessment Using Drosophila Wing Spot Test as an Alternative In Vivo Model for Genotoxicity Testing—A Review

Genomic instability, one of cancer’s hallmarks, is induced by genotoxins from endogenous and exogenous sources, including reactive oxygen species (ROS), diet, and environmental pollutants. A sensitive in vivo genotoxicity test is required for the identification of human hazards to reduce the potential health risk. The somatic mutation and recombination test (SMART) or wing spot test is a genotoxicity assay involving Drosophila melanogaster (fruit fly) as a classical, alternative human model. This review describes the principle of the SMART assay in conjunction with its advantages and disadvantages and discusses applications of the assay covering all segments of health-related industries, including food, dietary supplements, drug industries, pesticides, and herbicides, as well as nanoparticles. Chemopreventive strategies are outlined as a global health trend for the anti-genotoxicity of interesting herbal extract compounds determined by SMART assay. The successful application of Drosophila for high-throughput screening of mutagens is also discussed as a future perspective

Analysis of Phytonutrients, Anti-Mutagenic and Chemopreventive Effects of Tropical Fruit Extracts

Thailand is located in the tropics and a wide variety of fruits are grown commercially. However, studies regarding the phytonutrients, anti-mutagenic and chemopreventive effects of these fruits are limited. Thus, phytochemical profiles and inhibition of key enzymes involved in obesity and diabetes, together with anti-mutagenic and chemopreventive properties of eight tropical fruit extracts cultivated in Thailand, including Psidium guajava ‘Kimju’, Psidium guajava ‘Keenok’, Ananas comosus ‘Pattavia’, Ananas comosus ‘Phulae’, Durio zibethinus ‘Chanee’, Durio zibethinus ‘Monthong’, Carica papaya ‘Khaekdum’ and Mangifera indica ‘Namdokmai’ were investigated. Different cultivars were also compared. Results showed that M. indica ‘Namdokmai’ was the most antioxidant-rich extract containing abundant 4-hydroxybenzoic acid and its derivative, gallic acid, as the main phenolics. M. indica ‘Namdokmai’ also exhibited high inhibitory capacities (>60% inhibition under studied conditions) against lipase, α-amylase and α-glucosidase, key enzymes as drug targets for controlling obesity and type 2 diabetes. Interestingly, all fruit extracts suppressed food mutagen-induced DNA mutations assayed by the Ames test, especially M. indica ‘Namdokmai’ and C. papaya ‘Khaekdum’ (>50% inhibition at 200 µg/plate). The M. indica ‘Namdokmai’ was also the most potent extract for suppression of cancer promotion (>90% inhibition at 200 µg/mL) followed by P. guajava ‘Kimju’, P. guajava ‘Keenok’ and C. papaya ‘Khaekdum’. Results potentially indicated that fruit intake after overcooked meat consumption might supplement nutrients and fiber and also reduce DNA mutation sources

Enhancing Therapeutic Efficacy of Donepezil, an Alzheimer’s Disease Drug, by <i>Diplazium esculentum</i> (Retz.) Sw. and Its Phytochemicals

Alzheimer’s disease (AD) is the most common type of dementia and a significant concern to global public health due to the prevalence of aging populations. Donepezil is one of only a few medications approved for use as an anti-AD agent but all have adverse side effects. Reducing the dosage of AD drugs with plant extracts (phytotherapy) while maintaining efficacy is one strategy to minimize adverse side effects. We previously reported the anti-AD properties of an edible fern, Diplazium esculentum (Retz.) Sw. (DE), which inhibited key enzymes involved in AD pathogenesis including acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase 1 (BACE-1). This study aimed to determine whether DE exhibited a synergistic effect with donepezil. The enzyme inhibitory assay showed that DE extract and its bioactive compounds, kaempferol, and quercetin, slightly impeded AChE inhibition with donepezil, while DE extract and quercetin showed synergistic or additive effects with donepezil against BChE and BACE-1, respectively. DE extract combined with donepezil also improved eye phenotypes in a Drosophila model of AD by preventing ommatidia atrophia and bristle breakages. Furthermore, the DE extract exhibited no genotoxic activities, as determined by the Ames test. Our data revealed that DE extract showed promise when combined with donepezil during AD treatment by targeting BChE and BACE-1

<i>Mangifera indica</i> ‘Namdokmai’ Prevents Neuronal Cells from Amyloid Peptide Toxicity and Inhibits BACE-1 Activities in a <i>Drosophila</i> Model of Alzheimer’s Amyloidosis

Alzheimer’s disease (AD) is a progressive neurological illness with few effective treatments. Thus, ameliorating the effects of AD using natural products has attracted global attention with promising efficacy and safety. In this study, ten tropical fruits including Ananas comosus ‘Phulae’, Ananas comosus ‘Pattavia’, Carica papaya ‘Khaekdum’, Carica papaya ‘Khaeknuan’, Durio zibethinus ‘Monthong’, Durio zibethinus ‘Chanee’, Psidium guajava ‘Kimju’, Psidium guajava ‘Keenok’, Mangifera indica ‘Kaew’ and Mangifera indica ‘Namdokmai’ were screened for their inhibitory activities against the key enzymes, cholinesterases and β-secretase (BACE-1), involved in AD pathogenesis. The top three fruit extracts with promising in vitro anti-AD activities were further investigated using rat pheochromocytoma PC-12 neuronal cell line and Drosophila AD model. Data showed that M. indica ‘Kaew’, M. indica ‘Namdokmai’ and P. guajava ‘Kimju’ reduced Aβ1–42-mediated neurotoxicity by promoting glutathione-dependent enzymes, while M. indica ‘Namdokmai’ limited Aβ1–42 peptide formation via BACE-1 inhibition and amended locomotory behavior of the Drosophila AD model. Results indicated the potential anti-AD properties of tropical fruits, particularly M. indica ‘Namdokmai’ in the prevention of Aβ1–42-mediated neurotoxicity and as a BACE-1 blocker

High Pectin Recovery from Cocoa Husks Using an Autoclave Approach: An Analysis of Its Physicochemical, Structural, and Genotoxicity Properties

Pectin was extracted from cocoa husks, a food-processing biowaste, using an autoclave approach. A Box–Behnken design (BBD) and response surface methodology (RSM) were used to optimize pectin extraction. Three factors including extraction time (5–40 min), temperature (105–135 °C), and solid to liquid ratios (SLRs) (10–30 w/v) were employed. Results showed that the optimal conditions for high cocoa-husk-pectin (CHP) yield of 26.22% was 105 °C for 5 min with an SLR at 20 w/v. The physicochemical characteristics of CHP were compared with commercial high-methoxyl pectin (CHMP) and commercial low-methoxyl pectin (CLMP). CHP was classified as low-methoxyl pectin, with a degree of esterification at 34.74% and methoxyl content of 5.08%. The galacturonic acid content of CHP was 32.71% which was lower than CHMP (72.69%) and CLMP (41.24%). The intrinsic viscosity and viscosity–average molecular weight was similar to CLMP but higher than CHMP. No significant differences in water-holding capacity were found among samples. CHP showed higher oil-holding capacity but lower solubility compared with commercial pectin. CHP solutions showed pseudoplastic behavior. The viscosities of CHP solutions improved at increasing concentrations and decreasing pH. The CHP solution viscosities were lower than CLMP at the same condition. The viscoelastic properties of CHP solutions increased at higher concentrations, with the optimal value at pH 3. CHP showed no genotoxicity when assayed using the Ames test. Autoclave extraction as an accessible fast method showed potential for high pectin yield recovery from cocoa husks

Evaluation of Mutagenicity and Anti-Mutagenicity of Various Bean Milks Using Drosophila with High Bioactivation

The consumption of a nutritious diet including phytochemicals can minimize mutations as the primary cause of carcinogenesis. Bean consumption supplies calories, minerals and phytochemicals but their anti-mutagenic properties in vivo remain little understood. Hence, the present study aimed to study the mutagenicity and anti-mutagenic properties of five bean milks using the somatic mutation and recombination test (SMART) involving Drosophila with high bioactivation. Milk derived from five bean varieties, namely black bean (Phaseolus vulgaris), red kidney bean (Phaseolus vulgaris), mung bean (Phaseolus aureus), peanut (Arachis hypogaea) and soybean (Glycine max) did not induce DNA mutations in Drosophila with high bioactivation, indicating their genome-safe properties. All bean milks showed anti-mutagenicity against the food-derived mutagen, urethane, in vivo with different degrees of inhibition. In the co-administration study, larvae were treated with each bean milk together with urethane. Soybean milk showed the highest anti-mutagenicity at 27.75%; peanut milk exhibited the lowest at 7.51%. In the pre-feeding study, the larvae received each bean milk followed by urethane. Soybean milk exhibited the highest anti-mutagenic potential, followed by red kidney bean and black bean milks. Total phenolic and antioxidant data revealed that the anti-mutagenicity of both red kidney bean milk and black bean milk might be derived from their phenolic or antioxidant properties; other phytochemicals may contribute to the high anti-mutagenicity observed in soybean milk. Further investigations on the anti-mutagenicity of bean milks against other dietary mutagens are required to develop bean-based products with potent anti-mutagenic properties

Exploration of the nutritional and carotenoids profiles of vegetables in Thai cuisine as potential nutritious ingredients

Missing information on plant origin control and nutritional data on herbs, spices and vegetables could lead to sample quality deficit and misusage of the plant database. In this study, twenty vegetables that were collected and managed based on the recommendations of the Department of Agriculture, Ministry of Agriculture and Cooperatives, Thailand, were investigated regarding their proximate mineral, vitamin and carotenoid contents using the standard procedures of the Association of Official Analytical Chemists (AOAC). The results showed that these plants (100 g dry weight) exhibited similar energy levels (337.11–420.48 kcal), which were mainly distributed from high carbohydrate content (21.01–88.17 g), while protein (3.14–66.07 g) and fat (0.00–10.33 g) levels were quite low. As a form of carbohydrate, dietary fiber was found to be high in Cymbopogon citratus (DC.) Stapf (Cy. citratus) and Solanum torvum Sw. (So. torvum) (57.00–59.54 g). Interestingly, Senegalia pennata subsp. insuavis (Lace) Maslin, Seigler &amp; Ebinger (S. pennata) exhibited exceptionally high protein content, which was between 2.3 and 3.1 times higher than its carbohydrates. High mineral contents were detected in S. pennata, Ocimum africanum Lour. (O. africanum), Ocimum basilicum L. (O. basilicum), Ocimum gratissimum L. var. macrophyllum Briq. (O. gratissimum) and Coriandrum sativum L. (Co. sativum), while Mentha cordifolia Opiz ex Fresen (M. cordifolia) was observed to be a good source of vitamin C (381.36–547.47 mg). High carotenoids were mostly found in Eryngium foetidum L. (E. foetidum), O. gratissimum, Co. sativum and O. basilicum (75.23–119.96 mg). Interestingly, the location of sample collection seemed to have minimal effect on the nutritional and carotenoid compositions. The results of this study provide reliable information concerning the nutritional and carotenoid contents in plant sources with control of origin, which could be used in the future for food development with specific nutritional requirements

Liraglutide Suppresses Tau Hyperphosphorylation, Amyloid Beta Accumulation through Regulating Neuronal Insulin Signaling and BACE-1 Activity

Neuronal insulin resistance is a significant feature of Alzheimer&rsquo;s disease (AD). Accumulated evidence has revealed the possible neuroprotective mechanisms of antidiabetic drugs in AD. Liraglutide, a glucagon-like peptide-1 (GLP-1) analog and an antidiabetic agent, has a benefit in improving a peripheral insulin resistance. However, the neuronal effect of liraglutide on the model of neuronal insulin resistance with Alzheimer&rsquo;s formation has not been thoroughly investigated. The present study discovered that liraglutide alleviated neuronal insulin resistance and reduced beta-amyloid formation and tau hyperphosphorylation in a human neuroblostoma cell line, SH-SY5Y. Liraglutide could effectively reverse deleterious effects of insulin overstimulation. In particular, the drug reversed the phosphorylation status of insulin receptors and its major downstream signaling molecules including insulin receptor substrate 1 (IRS-1), protein kinase B (AKT), and glycogen synthase kinase 3 beta (GSK-3&beta;). Moreover, liraglutide reduced the activity of beta secretase 1 (BACE-1) enzyme, which then decreased the formation of beta-amyloid in insulin-resistant cells. This indicated that liraglutide can reverse the defect of phosphorylation status of insulin signal transduction but also inhibit the formation of pathogenic Alzheimer&rsquo;s proteins like A&beta; in neuronal cells. We herein provided the possibility that the liraglutide-based therapy may be able to reduce such deleterious effects caused by insulin resistance. In view of the beneficial effects of liraglutide administration, these findings suggest that the use of liraglutide may be a promising therapy for AD with insulin-resistant condition

Optimized Conditions for the Extraction of Phenolic Compounds from <i>Aeginetia indica</i> L. and Its Potential Biological Applications

Aeginetia indica L., a parasitic root in the Orobanchaceae family, is used as a food colorant in traditional Thai desserts. However, scant information is available on its food applications as well as medicinal properties, while overharvesting by the local people has severely depleted wild plant populations. This research, thus, aimed to extract optimized total phenolic content (TPC) in varying extraction conditions using response surface methodology (RSM) and the Box–Behnken design (BBD). Results indicated that an extraction temperature of 90 °C, 80% (v/v) aqueous ethanol, and 0.5% (w/v) solid-to-liquid ratio yielded the highest TPC at 129.39 mg gallic acid equivalent (GAE)/g dry weight (DW). Liquid chromatography–electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) identified the predominant phenolics as apigenin (109.06 mg/100 g extract) and luteolin (35.32 mg/100 g extract) with trace amounts of naringenin and rutin. Under the optimal extraction condition, the plant extract exhibited antioxidant activities of 5620.58 and 641.52 µmol Trolox equivalent (TE)/g DW determined by oxygen radical absorbance capacity (ORAC) and ferric ion reducing antioxidant power (FRAP) assay, while the scavenging capacity of total radicals at 50% (SC50) was determined to be 135.50 µg/mL using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The plant extract also exhibited inhibitory activities against the key enzymes relevant to type II diabetes, obesity, and Alzheimer’s disease, suggesting the potential for medicinal applications

Multi-Endpoint Toxicological Assessment of Chrysin Loaded Oil-in-Water Emulsion System in Different Biological Models

Chrysin is hypothesized to possess the ability to prevent different illnesses, such as diabetes, cancer, and neurodegenerative disorders. Nonetheless, chrysin has a low solubility under physiological conditions, resulting in limited bioavailability. In a previous study, we utilized an oil-in-water emulsion system (chrysin-ES or chrysin-NE) to encapsulate chrysin, thereby increasing its bioaccessibility and preserving its antioxidant and anti-Alzheimer’s properties. To promote the chrysin-ES as a supplementary and functional food, it was obligatory to carry out a safety assessment. Cytotoxicity testing showed that chrysin-ES was harmless, with no killing effect on 3T3-L1 (adipocytes), RAW 264.7 (macrophages), HEK293 (kidney cells), and LX-2 (hepatic stellate cells). The acute toxicity evaluation demonstrated that the 50% lethal dose (LD50) for chrysin-ES was greater than 2000 mg/kg BW. Genotoxicity assessments found that chrysin-ES did not induce DNA mutations in vitro or in vivo. Furthermore, chrysin and chrysin-ES exhibited anti-mutagenic properties against PhIP-induced and IQ-induced mutagenesis in the Ames test, while they inhibited urethane-, ethyl methanesulfonate-, mitomycin C-, and N-nitrosomethylurea-mediated mutations in Drosophila. The present study illustrates the safety and anti-genotoxicity properties of chrysin-ES, allowing for the further development of chrysin-based food supplements and nutraceuticals