"GC-MS profiling, sub-acute toxicity study and total phenolic and flavonoid content analysis of methanolic leaf extract of Schima wallichii (D.C.) Korth-a traditional antidiabetic medicinal plant".

ETHNOPHARMACOLOGICAL RELEVANCE: Schima wallichii (D.C.) Korth is traditionally used in Manipur, India for treatment of diabetes and hypertension. However, there is no data reported regarding safety profile of this medicinal plant upon repeated per oral administration over a period of time. AIM OF THE STUDY: In the current study phytochemical profile, toxicological profile and total phenolic and flavonoid compound content of Schima wallichii leaves extract were evaluated. MATERIALS AND METHODS: Gas chromatography coupled to mass spectrometry was performed for chemical profiling by using Gas Chromatography-Mass Spectrometry/Mass Spectrometry (GC-MS/MS), Shimadzu, TQ8040 system. A 28 days sub-acute toxicity study was carried out using albino Wistar rats by administering 3 different doses (200, 400 and 800 mg/kg body weight per oral) of methanol leaves extract. Changes in body weights were recorded weekly. Serum biochemical parameters were estimated as well as blood-cell count was done to check the effect of extract on haematopoietic system. Histopathology of vital organs viz. kidney, heart, brain, liver was performed to find any pathological indications. Since, liver is main the site for xenobiotic metabolism, estimation of the level of glutathione, catalase and lipid peroxidation were done. Further, total phenolic and flavonoid compound content estimation was performed for the leaves extract. RESULTS: GC-MS revealed 14 major compounds with area percentage >1% of which quinic acid, n-Hexadecanoic acid, 9,12,15-Octadecatrienoic acid, (Z,Z,Z)-, Octatriacontyl trifluoroacetate, are three major compounds. No mortality was observed after the treatment with extract. Blood-cell count and biochemical parameters didn't show significant deviation as compared to control group. Histopathology study of vital organs viz. (liver, kidney, heart and brain) showed normal cellular construction comparing to control group. There was no sign of membrane lipid peroxidation, depletion of catalase level and glutathione level in liver. The result demonstrates that NOAEL (no-observed-adverse-effect levels) in the sub-acute toxicity was above 800 mg/kg. The leaves extract showed significant total phenol and flavonoid content. CONCLUSION: The present study revealed that Schima wallichii possessed important bioactive compounds with therapeutic values. The plant was safe for consumption after repeated high doses administration in rats and possesses significant amount of total phenol and flavonoid content.

Bavachin induces liver injury and cell apoptosis by targeting Wnt/ß-catenin/DRP1 signaling pathway mediated mitochondrial dysfunction.

Psraleae Fructus (PF) is a well-known traditional Chinese medicine in China. While numerous liver injury reports caused by PF limits its clinical application. Bavachin, a flavonoid compound isolated from the fruits of Psoralea corylifolia L., has been validated to induce direct apoptosis in hepatocytes and liver tissues in our previous studies. However, the subcellular mechanisms of bavachin induced liver injury is still elusive. Here, utilizing 6-week-old C57BL/6 J mice and human embryonic hepatocytes (L02 cells), we report that bavachin activates dynamic-related protein 1 (DRP1) mediated excess mitochondrial fission and endoplasmic reticulum (ER) stress related apoptosis via Wnt/ß-catenin signaling pathway. Notably, DRP1 knockdown or XAV-939 induced Wnt/ß-catenin inhibition decreased bavachin-induced ER stress and cell apoptosis in L02 cells. In addition, bavachin impaired mitochondrial structural and function in the mice liver tissues. Mdivi-1, a mitochondrial fission inhibitor targeting DRP1, prevented bavachin-induced mitochondrial and ER structural damage, ER stress, and liver injury. Our results demonstrated that bavachin induced mitochondrial fission plays a crucial role in bavachin induced ER stress related liver injury, via the mechanism that involved activation of Wnt/ß-catenin signaling pathway.

An integrated strategy combining network toxicology and feature-based molecular networking for exploring hepatotoxic constituents and mechanism of Epimedii Folium-induced hepatotoxicity in vitro.

Epimedii Folium (EF), a commonly used herbal medicine to treat osteoporosis, has caused serious concern due to potential hepatotoxicity. Until now, its intrinsic hepatotoxic mechanism and hepatotoxic ingredients remain unclear. Here, a novel high-throughput approach was designed to investigate the intrinsic hepatotoxic of EF. High-content screen imaging (HCS) and biochemical tests were first performed to obtain the cytotoxicity parameter matrix of 17 batch EF samples. EF-treated alpha mouse liver 12 (AML12) cells showed increased reactive oxygen species (ROS), reduced glutathione (GSH) and mitochondrial membrane potential (MMP), and apoptosis and cholestasis were further observed. Network toxicology predicted that EF-triggered hepatotoxiciy was involved in transcription factor (TF) activity. The FXR expression, screened by a TF PCR array, exhibited down-regulation following EF extract administration. Moreover, EF inhibited bile acid (BA) metabolism pathway in an FXR-dependent manner. Pearson correlation between the cytotoxicity parameter matrix and quantification feature table obtained from UHPLC-QTOF data of EF suggested 7 prenylated flavonoids possessed potent hepatotoxicities and their cytotoxicity order was further summarized. The transcriptional repression effects of them on FXR were also verified. Collectively, our findings indicate that FXR is probably responsible for EF-induced hepatotoxicity and prenylated flavonoids may be a major class of hepatotoxic constituents in EF.

Glycoalkaloid Composition and Flavonoid Content as Driving Forces of Phytotoxicity in Diploid Potato.

Despite their advantages, biotechnological and omic techniques have not been applied often to characterize phytotoxicity in depth. Here, we show the distribution of phytotoxicity and glycoalkaloid content in a diploid potato population and try to clarify the source of variability of phytotoxicity among plants whose leaf extracts have a high glycoalkaloid content against the test plant species, mustard. Six glycoalkaloids were recognized in the potato leaf extracts: solasonine, solamargine, α-solanine, α-chaconine, leptinine I, and leptine II. The glycoalkaloid profiles of the progeny of the group with high phytotoxicity differed from those of the progeny of the group with low phytotoxicity, which stimulated mustard growth. RNA sequencing analysis revealed that the upregulated flavonol synthase/flavonone 3-hydroxylase-like gene was expressed in the progeny of the low phytotoxicity group, stimulating plant growth. We concluded that the metabolic shift among potato progeny may be a source of different physiological responses in mustard. The composition of glycoalkaloids, rather than the total glycoalkaloid content itself, in potato leaf extracts, may be a driving force of phytotoxicity. We suggest that, in addition to glycoalkaloids, other metabolites may shape phytotoxicity, and we assume that these metabolites may be flavonoids.

Acute and 13 weeks subchronic toxicological evaluation of the flavonoid-rich extract of Sophora flavescens.

The roots of Sophora flavescens have a long history of use in Chinese medicine for the treatment of various medical conditions. Flavonoids from the ethyl acetate extract of S. flavescens have shown anti-inflammatory, anticancer, and antidiabetic properties. The objective of this study was to evaluate the toxicological profile of a flavonoid-rich extract of S. flavescens (SFEA). We conducted acute and sub-chronic oral toxicity studies of SFEA in Kunming (KM) mice and Sprague-Dawley (SD) rats. Acute oral administration of 9.0 g/kg SFEA did not result in mortality, clinical signs of toxicity, or abnormal changes in the body weight or food consumption patterns. No significant changes in hematological, blood biochemical, or histopathological parameters were observed. A 13-week sub-chronic toxicity study was conducted in SD rats; the rats were orally administrated with various doses of SFEA (in mg/kg): 0 (control), 40, 80, 400, 800, and 1200. Mortality, clinical signs, or treatment-related changes in body weight, food consumption, hematological parameters, blood biochemical parameters, organ weights, or histopathological parameters were not observed. We found that SFEA is practically nontoxic to KM mice at a dose of 9.0 g/kg and that the no-observed-adverse-effect-level (NOAEL) of SFEA in SD rats is greater than 1200 mg/kg.

Ninety-day oral toxicological profiling of Kolaviron (an extract of Garcinia kola) in male and female rats.

There remains an insufficiency of data on the long-term toxicological profile of Garcinia kola Heckel and its extract, Kolaviron (KV), despite several studies on its pharmacological effects. This research was designed to investigate the long-term histopathological, hematological, biochemical, hormonal, reproductive, and oxidative effects of 90 days administration of KV to male and female rats, as well as additional 30 days reversibility study to assess the potential for reversal of induced effects. Fifty-six male and female Wistar rats divided into four groups were treated orally with distilled water/propylene glycol, 20 mg/kg KV, 100 mg/kg KV, and 500 mg/kg KV for 90 days. At the end of 90 days and 30 additional days of reversibility study, 5 ml blood was collected from animals for relevant analyses. Vital organs were harvested for histopathological assessments. In this study, KV did not elicit any adverse effect on histopathological presentations of vital organs which were generally non-abnormal. There was significant increase (p < 0.05) in LEU, MON, EOS%, BAS%, HCT (male animals) and LYM%, EOS%, BAS%, RBC, hemoglobin and MCH (female animals). There was significant diminution (p < 0.05) in cholesterol, triglycerides, LDL, and VLDL levels, with significant increase (p < 0.05) in HDL level in both male and female animals. KV elicited a non-significant increase in sperm count accompanied by a significant increase (p < 0.05) in levels of Follicle stimulating hormone (FSH) and testosterone in male rats. Furthermore, KV elicited significant (p < 0.001-0.05) elevation in the levels of GSH, SOD and CAT, and diminution in the level of MDA. The findings in this study suggest that long-term administration of KV is considerably safe with some variations in response between male and female animals. The possible sustenance of observed effects after cessation of KV administration, lipid lowering, erythropoiesis inducing, and immune system boosting activities of KV were confirmed in this study.

Safety assessment of marigold flavonoids from marigold inflorescence residue.

ETHNOPHARMACOLOGICAL RELEVANCE: Marigold flavonoids, extracted from marigold (Tagetes erecta L.) inflorescence residues, have attracted significant attention with respect to antioxidant, anti-inflammatory and chelating properties. However, the toxicity of marigold flavonoids have not yet been fully investigated. AIM OF THE STUDY: The main purpose of this study was to assess the safety of marigold flavonoids extracted from Marigold (Tagetes erecta L.) in order to provide information on its nonclinical safety. Thus, the acute oral toxicity, in vitro Ames test, sperm aberration study, bone marrow micronucleus test, subchronic oral toxicity test, and teratogenic potential were carried out in rats or mice. MATERIALS AND METHODS: For an acute oral toxicity test, SD rats and ICR mice (male and female, n = 5) orally received a single dose of 5000 mg/kg marigold flavonoids. Evaluation of marigold flavonoids genotoxic potential with a battery of tests, including an in vitro bacterial reverse mutation test using four mutant strains of Salmonella typhimurium (TA97、TA98、TA100、TA102), an sperm aberration test and an in vivo micronucleus test using bone marrow cells ICR mice that were orally administered marigold flavonoids, an subchronic oral toxicity study and teratogenic test employing male and female SD rats that were orally administered marigold flavonoids. All animals tests were completed in accordance with GB 15193 for toxicity tests. RESULTS: In the acute oral toxicity test, marigold flavonoids given at the dose of 5000 mg/kg body weight for 14 days didn't produce any abnormal clinical symptoms or mortality in SD rats and ICR mice (both sex, n = 5). There was no evidence of genotoxicity of marigold flavonoids based on the results of the in vitro bacterial reverse mutation test (up to 1250 µg/plate), the sperm aberration test (up to 5000 mg/kg body weight), the in vivo micronucleus test (up to 5000 mg/kg body weight), the subchronic oral toxicity study (up to 10 g/kg feed dose) and the teratogenic test (up to 1250 mg/kg body weight). CONCLUSIONS: We found that marigold flavonoids are safe with regard to acute toxicity in rats or mice as well as genotoxicity such as mutagenesis or clastogenesis under the present experimental conditions. These results might support the safety of marigold flavonoids as a potential therapeutic material for the traditional use of herbal medicines and for the further development of novel antioxidant.

A flavonoid-rich fraction of Monolluma quadrangula inhibits xanthine oxidase and ameliorates potassium oxonate-induced hyperuricemia in rats.

Hyperuricemia represents a risk factor for the progression of chronic kidney disease. Oxidative stress and inflammation are implicated in the mechanisms underlying hyperuricemia-mediated kidney injury. Monolluma quadrangula possesses several beneficial effects; however, its effect on hyperuricemia has not been investigated. This study evaluated the renoprotective and xanthine oxidase (XO) inhibitory activity of M. quadrangula in hyperuricemic rats. Phytochemical investigation revealed the presence of six known flavonoid isolated for the first time from this species. The rats received M. quadrangula extract (MQE) and potassium oxonate (PO) for 7 days. In vitro assays showed the radical scavenging and XO inhibitory activities of MQE, and in silico molecular docking revealed the inhibitory activity of the isolated flavonoids towards XO. Hyperuricemic rats showed elevated serum uric acid, creatinine, urea, and XO activity, and renal pro-inflammatory cytokines, MDA and NO, and decreased GSH, SOD, and catalase. MQE ameliorated serum uric acid, urea, creatinine, and XO activity, and renal pro-inflammatory cytokines. In addition, MQE attenuated renal oxidative stress, enhanced antioxidants, downregulated URAT-1, and GLUT-9 and upregulated OAT-1 in PO-induced rats. In conclusion, M. quadrangula attenuated hyperuricemia and kidney impairment by suppressing XO activity, oxidative stress and inflammation, and modulating urate transporters.

Standardization, in-silico and in-vivo safety assessment of methanol extract of Ziziphus mauritiana Lam leaves.

Ziziphus mauritana Lam leaves were used to treat asthma, diabetes, pain, and inflammation in the Indian traditional system of medicine. The leaves of the Ziziphus mauritiana Lam were consumed as a vegetable in Indonesia and India. The present study aims to predict the pharmacokinetic properties of flavonoids identified & quantified through U(H)PLC and to evaluate the safety of methanol extract of Ziziphus mauritana Lam leaves (MEZ) in rats. A U(H)PLC-ESI-QTOF-MS/MS was performed to identify flavonoids present in MEZ and quantified using U(H)PLC method. The in-silico ADME properties of the flavonoids were analyzed using Schrodinger Maestro software. The acute oral toxicity study was performed by administering a single dose of MEZ (5000 mg/kg) in female rats and observed for 14 days. The sub-chronic studies were carried out by oral administration of MEZ at 500, 750, and 1000 mg/kg daily for 90 days. The changes in hematological parameters, clinical biochemistry, and histopathology were observed after the treatment period. Eight flavonoids rutin, kaempferol, luteolin, myricetin, catechin, and apigenin were identified from were identified in UPLC-QTOF-MS/MS analysis. These results showed the highest amount of luteolin (5.41 µg/ml) and kaempferol (4.02 µg/ml) present in MEZ. No signs of toxicity or mortality were observed in acute toxicity studies. In the sub-chronic studies, data showed that MEZ does not produce any changes in hematological and clinical biochemical parameters compared to control rats. MEZ (1000 mg/kg) significantly (p < 0.05) reduced total cholesterol, triglycerides, in male rats, which was more prominent on day 90. The histopathological analysis also revealed no changes in the vital organs. These results conclude that MEZ was considered safe and well-tolerated in rats.

The chemical composition of different leaf extracts of Lantana fucata Lindl. influences its cytotoxic potential: A study using the Allium cepa model.

ETHNOPHARMACOLOGICAL RELEVANCE: One of the most popular plants used to treat diseases in Brazil is Lantana fucata. Like most herbal medicines, its consumption is based on popular knowledge, which, despite being considered effective, may cause side effects. AIM OF THE STUDY: Since the scientific data on the pharmacological properties of L. fucata are still incipient, this research aimed to evaluate the cytotoxic and genotoxic potential of different types of extracts (infusion, aqueous and hydroalcoholic), characterizing them chemically. MATERIALS AND METHODS: The cytotoxicity assay was performed by the A. cepa model. The cytotoxicity parameters studied were number of dividing cells and percentage mitotic index (%MI). RESULTS: The result of the A. cepa assay showed that there was a decrease in the number of dividing cells and the percentage mitotic index as concentrations increased, for all extracts, indicating cytotoxicity. However, the hydroalcoholic extract was the most cytotoxic. Chromatography analysis allowed the characterization of secondary metabolites in the extracts, which were very similar. However, a greater abundance of flavonoids and triterpenoids was observed in the hydroalcoholic extract, suggesting that these compounds are responsible for its greater toxicity. CONCLUSIONS: Since the highest doses of extracts showed to have a cytotoxic effect, it is suggested that the ingestion of this species occurs in a moderate way.

Comparative study of the genotoxic activity of Artemisia vulgaris L. and Artemisia alba Turra extracts in vitro.

In this study, the genotoxic activity of acetone and aqueous extracts of two species of genus Artemisia (Artemisia vulgaris L. and Artemisia alba Turra), and possible role of their polyphenolic composition in the observed activities were investigated. Polyphenolic contents were evaluated by high-performance liquid chromatography (HPLC-PDA), while the genotoxic activity was tested using cytokinesis block micronucleus (CBMN) assay on human peripheral blood lymphocytes (PBLs) in vitro. HPLC-PDA showed that both A. alba extracts were richer in polyphenolic contents than A. vulgaris extracts. The acetone A. alba extract was the richest of polyphenolic content where we detected six phenolic acids and two flavonoids. CBMN assay showed that aqueous extract of A. vulgaris significantly increased micronucleus (MN) frequency in the PBLs treated with all tested concentrations (10, 50, 100, and 250 µg/mL), while A. alba did not significantly affect the mean MN frequency. Further, both acetone extracts were genotoxic in all tested concentrations, except the lowest tested (10 µg/mL) of A. alba. All tested extracts affected the nuclear division index (NDI) except the aqueous A. alba extract (p < 0.05). Based on our results, we can conclude that both acetone and aqueous A. vulgaris extracts and A. alba acetone extract were genotoxic in PBLs in vitro. A. alba aqueous extract was not genotoxic and cytotoxic in tested concentrations. We suggest that the aqueous extract of A. alba can be used in treatment, which has been confirmed by traditional medicine, but with a high dose of caution and not in high concentrations.

Glabrol impurity exacerbates glabridin toxicity in zebrafish embryos by increasing myofibril disorganization.

ETHNOPHARMACOLOGICAL RELEVANCE: Glabridin, extracted from Glycyrrhiza glabra L., is widely used for the treatment of hyperpigmentation because of its anti-inflammatory and antioxidant activities and its ability to inhibit melanin synthesis. This led to the strict regulation of its quality and safety. However, traditional quality control methods used for plant extracts cannot reflect the product quality owing to multiple unknown impurities, which necessitates the further analysis of impurities. AIM OF THE STUDY: The study identified the toxic impurities of glabridin and their toxicological mechanism. MATERIALS AND METHODS: In total, 10 glabridin samples from different sources were quantified using high-performance liquid chromatography. Sample toxicities were evaluated using zebrafish and cell models. To identify impurities, samples with different toxicity were analyzed by ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry. The toxicity of related impurities was verified in the zebrafish model. Phalloidin stain was used to evaluate subtle changes in myofibril alignment. RESULTS: Although glabridin content in the samples was similar, there were significant differences in toxicity. The results were verified using four different mammalian cell lines. Higher contents of glabrone and glabrol were identified in the sample with the highest toxicity. In the zebrafish model, the addition of glabrol reduced the LC50 of glabridin to 9.224, 6.229, and 5.370 µM at 48, 72, and 96 h post-fertilization, respectively, whereas glabrone did not have any toxic effect. Phalloidin staining indicated that a glabrol impurity exacerbates the myotoxicity of glabridin in zebrafish embryos. CONCLUSION: Glabrol, but not glabrone, was identified as a key impurity that increased glabridin toxicity. This finding indicates that controlling glabrol content is necessary during glabridin product production.

Polyphenols as anticancer agents: Toxicological concern to healthy cells.

Polyphenols are a group of diverse chemical compounds present in a wide range of plants. Various biological properties such as antiallergic, antiviral, antibacterial, anticarcinogenic, antiinflammatory, antithrombotic, vasodilatory, and hepatoprotective effect of different polyphenols have been reported in the scientific literature. The major classes of polyphenols are flavonoids, stilbenoids, lignans, and polyphenolic acids. Flavonoids are a large class of food constituents comprising flavones, isoflavanones, flavanones, flavonols, catechins, and anthocyanins sub-classes. Even with seemingly broad biological activities, their use is minimal clinically. Among the other concurrent problems such as limited bioavailability, rapid metabolism, untargeted delivery, the toxicity associated with these polyphenols has been a topic of concern lately. These polyphenols have been reported to result in different forms of toxicity that include organ toxicity, genotoxicity, mutagenicity, cytotoxicity, etc. In the present article, we have tried to unravel the toxicological aspect of these polyphenols to healthy cells. Further high-quality studies are needed to establish the clinical efficacy and toxicology concern leading to further exploration of these polyphenols.

Evaluation of in vitro cytotoxicity and in vivo potential toxicity of the extract from in vitro cultivated Anoectochilus roxburghii Lindl.

Anoectochilus roxburghii Lind. (A. roxburghii) has promising anti-oxidant, hyperglycemic, hepatoprotective, and immunomodulatory activities as well as anti-tumor effects. However, the pharmacological actions of in vitro cultured plants remain to be determined. Therefore, the objective of the study was to assess in vitro cytotoxicity and in vivo potential toxicity of an extract derived from in vitro cultivated A. roxburghii, termed as iARE. The total flavonoid content and predominant flavonoid compounds of extract were identified and quantitatively analyzed. The in vitro cytotoxicity of iARE was examined using several cancer and normal cell lines. The apoptotic activity and expression of apoptosis-associated genes were also examined in MCF7 cells to determine the underlying mechanisms related to anti-proliferative effects. In vivo potential toxicity of iARE was assessed following acute and subchronic oral administration in Sprague Dawley rats. Quercetin, kaempferol, and isorhamnetin were three flavonoid components identified in iARE. The extract exerted cytotoxic effects on various cancer cells but not normal fibroblasts. Apoptosis in MCF7 cells was induced by iARE in a concentration-dependent manner associated with increased Bax/Bcl-2 ratio and reduced mitochondrial membrane potential ΔΨm, leading to release of cytochrome c, activation of caspase-3/7 and caspase-9, and cleavage of PARP. In the acute oral toxicity study, no mortality or toxicological signs were observed in rats at 1000 or 5000 mg/kg. In a subchronic oral toxicity study, iARE at a dosage of up to 1000 mg/kg produced no mortality or treatment-related adverse effects on general behavior, food intake, body weight, relative organ weights. No apparent marked changes in the histopathology of the liver and kidney were detected. Data demonstrated that iARE induced in vitro cytotoxic effects in cancer cells are associated with lackof invivo toxicity. Thus, iARE was suggested to be considered as apotential therapeutic candidate for cancer treatment.

Comprehensive evaluation of two Astragalus species (A. campylosema and A. hirsutus) based on biological, toxicological properties and chemical profiling.

Astragalus L. (Fabaceae) is an important genus with numerous species having various traditional medicinal uses making them of interest for scientific investigations to ascertain their therapeutic benefits. In the present study, the quantitative polyphenolic profiles of methanolic extracts from different parts (leaves, flowers, and roots) of two endemic Astragalus species growing in Turkey, i.e. A. campylosema Boiss. and A. hirsutus Vahl were determined, along with their antioxidant and enzyme inhibitory properties. A. campylosema and A. hirsutus extracts showed varying total phenolic (25.80-40.60 and18.59-29.46 mg GAE/g, respectively) and total flavonoid (11.21-105.91 and 16.06-131.91 mg RE/g, respectively) contents. HPLC-MS/MS revealed rutin to be the predominant phenolic compound in all the extracts of A. campylosema and leaf extract of A. hirsutus (133.53-752.42 µg g-1), while hyperoside was the major one in the flower and root extracts of A. hirsutus (2014.07 and 123.13 µg g-1, respectively). In DPPH and ABTS assays, radical scavenging capacity was demonstrated by all extracts of A. campylosema (47.13-48.10 and 87.03-115.36 mg TE/g, respectively) and A. hirsutus (17.82-38.67 and 47.84-57.29 mg TE/g, respectively). Reducing activity was also displayed by the extracts in CUPRAC and FRAP assays (A. campylosema: 83.06-135.20 and 59.15-90.19 mg TE/g, respectively; A. hirsutus: 53.02-83.42 and 31.25-43.25 mg TE/g, respectively). All extracts were also found to act as metal chelators (12.32-21.45 mg EDTAE/g) and exhibited total antioxidant capacity ranging from 1.16 to 1.60 mmol TE/g, in phosphomolybdenum assay. Acetyl- and butyryl-cholinesterase inhibitory effects were observed by all the extracts of the two species (1.56-4.99 mg GALAE/g). Anti-hyperpigmentation potential by inhibiting tyrosinase (54.55-67.35 mg KAE/g) was reported as well. Carbohydrate hydrolyzing enzymes, amylase and glucosidase were also inhibited (0.22-1.03 mmol ACAE/g). Overall, A. campylosema extracts showed relatively better antioxidant and enzyme inhibitory potentials compared to A. hirsutus extracts. Strikingly, A. hirsutus extracts was found to have higher AGE inhibition activity than A. campylosema. Although the cytotoxic effect of three different organs obtained from A. campylosema and A. hirsutus increased depending on the dose (from 10 to 200 µg/mL), it was found that both plant extracts did not show a genotoxic effect at the highest concentration of 200 µg/mL. Indeed, data amassed from this current scientific work showed the two selected Astragalus species to be rich in bioactive polyphenols that could be responsible for the various pharmacological activities and hence demands to be further explored for their possible applications as natural health promoting agents.

In vitro anti-Acanthamoeba activity of flavonoid glycosides isolated from Delphinium gracile, D. staphisagria, Consolida oliveriana and Aconitum napellus.

Acanthamoeba spp. are widely distributed in the environment and cause serious infections in humans. Treatment of Acanthamoeba infections is very challenging and not always effective which requires the development of more efficient drugs against Acanthamoeba spp. The purpose of the present study was to test medicinal plants that may be useful in the treatment of Acanthamoeba spp. Here we evaluated the trophozoital and cysticidal activity of 13 flavonoid glycosides isolated from Delphinium gracile, D. staphisagria, Consolida oliveriana and from Aconitum napellus subsp. Lusitanicum against the amoeba Acanthamoeba castellanii. AlamarBlue Assay Reagent® was used to determine the activity against trophozoites of A. castellanii, and cytotoxic using Vero cells. Cysticidal activity was assessed on treated cysts by light microscopy using a Neubauer chamber to quantify cysts and trophozoites. Flavonoids 1, 2, 3 and 4 showed higher trophozoital activity and selectivity indexes than the reference drug chlorhexidine digluconate. In addition, flavonoid 2 showed 100% cysticidal activity at a concentration of 50 µm, lower than those of the reference drug and flavonoid 3 (100 µm). These results suggest that flavonoids 2 and 3 might be used for the development of novel therapeutic approaches against Acanthamoeba infections after satisfactory in vivo evaluations.

Screening of hepatotoxic compounds in Psoralea corylifolia L., a traditional Chinese herbal and dietary supplement, using high-resolution mass spectrometry and high-content imaging.

Owing to the complexity of the composition of herbal and dietary supplements, it is a challenging problem to efficiently screen and identify active or toxic compounds. Psoralea corylifolia L. (PCL) was selected as the subbject to establish a methodology for rapid screening and identification of hepatotoxic compounds. High-content imaging, ultra-performance liquid chromatography and high-resolution mass spectrometry were used in this study to detect the hepatotoxicity and identify unknown compounds in PCL samples. Then, putative toxic compounds which are highly related to hepatotoxicity were screened by spectrum-toxicity correlation analysis, and the toxicity intensity verified by high-content imaging. The maximum nontoxic dose of processed samples with good detoxification effect reduced more than 9 times compared with unprocessed raw medicinal materials. Spectrum-toxicity correlation analysis showed that bavachinin A, bavachin, isobavachalcone and neobavaisoflavone had high correlation with the hepatotoxicity of PCL, and psoralen and isopsoralen had low correlation with hepatotoxicity. This study verified the hepatotoxicity of these six putative compound monomers, proving the results of spectrum-toxicity correlation analysis. Based on the correlation analysis of high-resolution mass spectrometry of detection compounds and high-content imaging of hepatocyte toxicity data, the potential toxic compound of herbal and dietary supplement products can be quickly and accurately screened.

Flavonoids and hERG channels: Friends or foes?

The cardiac action potential is regulated by several ion channels. Drugs capable to block these channels, in particular the human ether-à-go-go-related gene (hERG) channel, also known as KV11.1 channel, may lead to a potentially lethal ventricular tachyarrhythmia called "Torsades de Pointes". Thus, evaluation of the hERG channel off-target activity of novel chemical entities is nowadays required to safeguard patients as well as to avoid attrition in drug development. Flavonoids, a large class of natural compounds abundantly present in food, beverages, herbal medicines, and dietary food supplements, generally escape this assessment, though consumed in consistent amounts. Continuously growing evidence indicates that these compounds may interact with the hERG channel and block it. The present review, by examining numerous studies, summarizes the state-of-the-art in this field, describing the most significant examples of direct and indirect inhibition of the hERG channel current operated by flavonoids. A description of the molecular interactions between a few of these natural molecules and the Rattus norvegicus channel protein, achieved by an in silico approach, is also presented.

Neurotoxic Effect of Flavonol Myricetin in the Presence of Excess Copper.

Oxidative stress (OS) induced by the disturbed homeostasis of metal ions is one of the pivotal factors contributing to neurodegeneration. The aim of the present study was to investigate the effects of flavonoid myricetin on copper-induced toxicity in neuroblastoma SH-SY5Y cells. As determined by the MTT method, trypan blue exclusion assay and measurement of ATP production, myricetin heightened the toxic effects of copper and exacerbated cell death. It also increased copper-induced generation of reactive oxygen species, indicating the prooxidative nature of its action. Furthermore, myricetin provoked chromatin condensation and loss of membrane integrity without caspase-3 activation, suggesting the activation of both caspase-independent programmed cell death and necrosis. At the protein level, myricetin-induced upregulation of PARP-1 and decreased expression of Bcl-2, whereas copper-induced changes in the expression of p53, p73, Bax and NME1 were not further affected by myricetin. Inhibitors of ERK1/2 and JNK kinases, protein kinase A and L-type calcium channels exacerbated the toxic effects of myricetin, indicating the involvement of intracellular signaling pathways in cell death. We also employed atomic force microscopy (AFM) to evaluate the morphological and mechanical properties of SH-SY5Y cells at the nanoscale. Consistent with the cellular and molecular methods, this biophysical approach also revealed a myricetin-induced increase in cell surface roughness and reduced elasticity. Taken together, we demonstrated the adverse effects of myricetin, pointing out that caution is required when considering powerful antioxidants for adjuvant therapy in copper-related neurodegeneration.

Hepatotoxic Effect of Lafoensia pacari A. St. Hil. (Lythraceae) on a Diet-Induced Obese Mice Model.

BACKGROUND: Brazilian flora is rich in plants with medicinal properties, which though popular, has contributed to the development of a range of phytotherapic products that use plants to treat and cure diseases. However, studies that use Brazilian plants in the treatment of metabolic disorders are still scarce in the literature. OBJECTIVE: The aim of this study was to analyze the effect of hepatotoxicity Lafoensia pacari on the metabolism of mice with obesity induced by a high-fat diet and to verify the phytochemical difference between the Lafoensia pacari bark of the trunk, leaves, and branches. METHODS: The plant material was collected from April to May in the municipality of Bonito de Minas, MG, Brazil. Qualitative tests for the presence of secondary metabolite classes were performed for leaves, branches and bark of the trunk. Through histological analysis, we evaluated hepatocytes and cell lesions in the liver. RESULTS: The comparative phytochemical analysis of the plant did not reveal alterations between the different plant parts. The phytochemical test showed that is preferable to use the leaves to make the extract to be applied, aiming to reduce the plant aggression. After treatment, greater changes were observed in the animals that received the high-fat diet and the hydroethanolic extract; the levels of AST, ALT, albumin and creatinine that were increased, thus demonstrating a possible toxicity. There were no significant differences in body weight. In the histological analysis, the animals without plant treatment displayed decreased liver weight and reduction in the inflammatory infiltrate. CONCLUSION: We conclude that Lafoensia pacari should be better evaluated for oral consumption and may cause liver damage.