Flavonoids: old and new aspects of a class of natural therapeutic drugs

Wikstroemiaganpi Extract Improved Atopic Dermatitis-Like Skin Lesions via Suppression of Interleukin-4 in 2,4-Dinitrochlorobenzene-Induced SKH-1 Hairless Mice

Plants of the genus Wikstroemia are used in Chinese traditional medicine to treat inflammatory diseases, such as arthritis, bronchitis, and pneumonia. The present study was designed to determine whether Wikstroemia ganpi (Siebold and Zucc.) Maxim. offers a potential means of treating 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Symptoms such as redness, edema, and keratinization in AD mice induced by DNCB were alleviated by the co-application of an ethanolic extract of W. ganpi for 2 weeks. The severity of skin barrier function damage was evaluated by measuring TEWL (transepidermal water loss). TEWLs of DNCB sensitized mouse dorsal skin were reduced by the application of a W. ganpi ethanolic extract, and skin hydration was increased. In addition, the infiltration of inflammatory cells into the dermis was significantly reduced, as were blood levels of IgE and IL-4, which play an important role in the expression of AD. The results of this experiment suggest that W. ganpi is a potential therapeutic agent for AD.

Preparation of hydroxy genkwanin nanosuspensions and their enhanced antitumor efficacy against breast cancer

Hydroxy genkwanin (HGK), a flavonoid compound from natural resources, showed good inhibition against the growth of breast tumor cells. However, the poor solubility restricted the further study and the in vivo drug delivery of HGK. We prepared HGK nanosuspensions by antisolvent precipitation method and investigated their characterization, stability, hemolysis probability, release behavior in vitro, antitumor activity in vitro and in vivo, and preliminary safety through acute toxicity experiments. The resultant HGK nanosuspensions (HGK-NSps) showed an average diameter of (261.1 ± 4.8 nm), a narrow particle size distribution (PDI of 0.12 ± 0.01), spherical morphology, high drug-loading content (39.9 ± 2.3%, w/w), and good stability in various physiological media. HGK-NSps was safe for intravenous injection at low concentration and HGK was slowly released from the obtained nanosuspensions. HGK-NSps showed stronger cytotoxicity than free HGK against many tumor cells in vitro. Especially against MCF-7 cells, the IC₅₀ value was decreased to 1.0 μg/mL, 5-fold lower than the HGK solution. In the in vivo antitumor activity study HGK-NSps (40 mg/kg) displayed a similar therapeutic effect to that of the paclitaxel injection (8 mg/kg). The preliminary acute toxicity test showed that even at the highest dose of 360 mg/kg (iv), HGK-NSps had 100% of mice survival and all the mice were in a good state, suggesting a maximum tolerated dose more than 360 mg/kg. The effective antitumor effect and good tolerance showed HGK-NSps were likely to become a safe and effective antitumor drug for the treatment of breast cancer in the future.

Chalcones and Bis-Chalcones Analogs as DPPH and ABTS Radical Scavengers

Background:

A number of synthetic scaffolds, along with natural products, have been identified as potent antioxidants. The present study deals with the evaluation of varyingly substituted, medicinally distinct class of compounds “chalcones and bis-chalcones” for their antioxidant potential.

Methods:

In vitro radical scavenging activities were performed on a series of synthetic chalcones 1- 13 and bis-chalcones 14-18.

Results:

All molecules 1-18 revealed a pronounced 2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2ʹ- azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals scavenging potential in the ranges of IC50s = 0.58 ± 0.14 - 1.72 ± 0.03 and 0.49 ± 0.3 - 1.48 ± 0.06 μM, respectively. Ascorbic acid (IC50s = 0.5 ± 0.1 and 0.46 ± 0.17 μM for DPPH and ABTS, respectively) was used as a standard radical scavenger.

Conclusion:

Structure-activity relationship (SAR) revealed an active participation of various groups, including -SMe and -OMe in scavenging activity.

Analytical determinations of luteolin

Plants, through the photosynthesis process, produce the substances necessary for all the life cycles of nature, which are called "primary metabolites." Moreover, there are some plants that synthesize, in addition to these, other substances with more specific functions, which are known as "secondary metabolites." It is inside this group that flavonoids are located, whose main function is to protect organisms from damage caused by different oxidizing agents. Luteolin (3,4,5,7-tetrahydroxy-flavone) belongs to the sub-class of flavonoids known as flavones and is one of 10,000 flavonoids currently known, being one of the most bio-active flavonoids. Its various beneficial properties for health, together with the increasing reduction in the use of synthetic antioxidants, make the study of luteolin a very active field. Within this, the quantification of this molecule has become a subject of very special interest given that it is transversal to all fields. In this review article, we aim to give the reader a broad and deep vision of this topic, focusing on the events reported in the last 5 years and covering all possible techniques related to analytical determinations. We will discuss in terms of advantages and disadvantages between techniques, selectivity, sensitivity, costs, time consumption, and reagents as well as in the complexity of operations.

The Therapeutic Potential of Quercetin in Parkinson's Disease: Insights into its Molecular and Cellular Regulation

Parkinson's disease (PD) is a chronic and progressive neurodegenerative disorder characterized by the progressive death of dopaminergic neurons in the substantia nigra pars compacta (SNc). PD is a multifactorial disorder, with several different factors being suggested to play a synergistic pathophysiological role, including oxidative stress, autophagy, underlying pro-inflammatory events and neurotransmitters abnormalities. Overall, PD can be viewed as the product of a complex interaction of environmental factors acting on a given genetic background. The importance of this subject has gained more attention to discover novel therapies to prevent as well as treat PD. According to previous research, drugs used to treat PD have indicated significant limitations. Therefore, the role of flavonoids has been extensively studied in PD treatment. Quercetin, a plant flavonol from the flavonoid group, has been considered as a supplemental therapy for PD. Quercetin has pharmacological functions in PD by controlling different molecular pathways. Although few studies intended to evaluate the basis for the use of quercetin in the context of PD have been conducted so far, at present, there is very little evidence available addressing the underlying mechanisms of action. Various principal aspects of these treatment procedures remain unknown. Here, currently existing knowledge supporting the use of quercetin for the clinical management of PD has been reviewed.

Evaluation of Hepatoprotective Activity of Caralluma europaea Stem Extract against CCl4-Induced Hepatic Damage in Wistar Rats

The present study aims to evaluate the hepatoprotective activity of stem aqueous extract of Caralluma europaea (AECe) on carbon tetrachloride- (CCl₄-) induced hepatic damage in Wistar rats. The animals were daily treated with the aqueous extract of C. europaea at a dose of 250 mg/kg body weight for 14 days. CCl₄ was injected (1 ml/kg, i.p.) two times, on the 7^th and 14^th days. At the end of the experimental period, all rats were anesthetized to collect blood for the assessment of biochemical parameters and then sacrificed to collect the liver for weighing. Hepatotoxicity was evaluated by measuring the serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin (total and direct), malondialdehyde (MDA), total protein (TP), triglycerides (TG), total cholesterol, very low-density lipoprotein (VLDL-c ), low-density lipoprotein (LDL-c), high-density lipoprotein (HDL-c), urea, creatinine, and uric acid. Based on the results obtained in this study, the administration of C. europaea before exposure to the administration of CCl₄ conferred favorable hepatoprotective effect in rats. The treatment with AECe (250 mg/kg) exhibits a significant hepatoprotective effect by ameliorating CCl₄-induced alterations of these biochemical parameters. Hence, C. europaea could be a potential medicinal herb that can be used in the future to prevent liver intoxication.

In vitro Antioxidant and Cytotoxic Activities of Extracts of Endemic Tanacetum erzincanense Together with Phenolic Content by LC-ESI-QTOF-MS

In this study, phenolic composition, and in vitro biological activities of ethyl acetate (EAE) and methanol (ME) extracts obtained from the aerial parts of endemic Tanacetum erzincanense were investigated. Total phenolic and flavonoid content of the extracts were determined by Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. Antioxidant capacity of the extracts was evaluated over radical scavenging (DPPH and ABTS) and metal ion reducing power (FRAP and CUPRAC) tests. Individual phenolic compounds in ME was analyzed by high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS). Cell inhibitory potential of the extracts was tested against colorectal adenocarcinoma (HT-29), breast adenocarcinoma (MCF-7), and hepatocarcinoma (HepG2) cells by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. The results showed that ME contains higher TPC (64.4 mg GAE/g) and TFC (62.2 mg QE/g) than those of EAE (41.5 mg GAE/g and 40.0 mg QE/g). LC-ESI-QTOF/MS analysis revealed that ME is rich in phenolic compounds, namely, chlorogenic acid, apigenin, quercetin, luteolin, and diosmetin. Antioxidant assay results indicated that ME possess stronger activity than EAE and a power that competes with synthetic antioxidants. XTT assay results demonstrated that although both extracts displayed a considerable cytotoxicity against the tested cancer cell lines in a time and dose-dependent manner, ME expressed its selective inhibitory action towards MCF-7 cells with an IC₅₀ value of 20.4 μg/mL for 72 h. These results may serve as a basis for further in vivo studies to examine the potential applications of T. erzincanense in food and pharmaceutical industries.

ZnCl2 catalyzed new coumarinyl-chalcones as cytotoxic agents

A new series of coumarin-yl-chalcone derivatives (3a-m) had been designed and synthesized through different reactions such as aromatic addition, cyclization and Claisen-Schmidt reactions in good yields (54–78%). 5-acetyl-4-(2-hydroxyphenyl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (1) has been synthesized by multi-component one pot reaction of salicylaldehyde, methyl acetoacetate and urea, which was further reacted with malonic acid employing ZnCl₂ catalyst to yield 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H) -one (2). The title compounds (3a-m) were synthesised by reacting 5-acetyl-4-(4-hydroxy-2-oxo-2H-chromen-8-yl) -6-methyl-3, 4-dihydropyrimidin-2(1H)-one (2) with different aromatic aldehydes in the presence of potassium hydroxide. In silico studies, a preliminary screening method for predicting the anti-cancer activity was performed for the synthesized compounds (3a-m) against Src, Alb tyrosine kinase and homology model protein (PDB ID: 4csv). The derivatives 3h and 3m showed moderate binding energies. The in vitro cytotoxic activity was evaluated for the compounds 3h and 3m by using human cancer cell-line morphology and MTT assay against three human cell-lines A549 (Lung), Jurkat (Leukemia) and MCF-7 (Breast). The results indicate that the derivatives 3h and 3m display significant anti-cancer activity, however it was found to be less cytotoxic when compared to the standard used i.e. Imatinib.

Anti-inflammatory activity of Jatropha curcas L. in brain glial cells primary cultures

ETHNOPHARMACOLOGICAL RELEVANCE

Jatropha curcas L. (Euphorbiaceae), a medicinal plant known in Brazil as "Pinhão Manso", is highly adaptable, being cultivated in different tropical and subtropical regions of the world. Antimicrobial, antioxidant and antiinflammatory activities have been attributed to different parts of the plant. In the central nervous sytem (CNS), neuroinflammation is mediated by glial cells, mainly by astrocytes and microglia, a process that plays an important role in neurodegenerative diseases and other CNS disorders. In this study, we investigated the anti-inflammatory activity of the methanolic extract obtained from the leaves of J. curcas L. (MEJc) in primary cultures of glial cells submited to inflammatory stimulus.

MATERIALS AND METHODS

Primary cultures of glial cells obtained from the cerebral cortex of neonate Wistar rats were treated with MEJc (0.1-50,000 μg mL^-1) and its fractions (F_nJc) (0.1 μg mL^-1) with or without lipopolysaccharide of Escherichia coli (LPS) (1 μg mL^-1). Cell viability was determined with MTT test. Modifications in glial cell morphology were investigated by means of phase contrast microscopy and May-Grünwald staining. The reactivity of astrocytes and microglia were investigated with immunocytochemistry for GFAP, Iba1 and transcription factor NF-kB, as well as with Greiss reaction to determine the nitric oxide (NO) production.

RESULTS

MEJc at 0.1-1000 μg mL^-1 was non-toxic to glial cells and the DE₅₀ was 10.794 μg mL^-1. The treatment with LPS induced the activation of astrocytes and microglia marked by morphological modifications and changes in the expression of GFAP and Iba1, as well as the increase in NF-kB expression and NO production. Treatment with MEJc inhibited the morphological modifications, changes in GFAP and Iba1 expression, and the increase in NF-kB and NO production induced by LPS.

CONCLUSION

This study demonstrates that the MEJc and its fractions modulate inflammatory response of astrocytes and microglia to LPS and may be considered as a potential therapeutic strategy for neuroinflammation-related diseases.

Pharmacological Properties of Allium cepa, Preclinical and Clinical Evidences; A Review

Onion or Allium cepa (A. cepa) is one of the most important condiment plants grown and consumed all over the world. This plant has various therapeutic effects attributed to its constituents, such as quercetin, thiosulphinates and phenolic acids. In the present article, various pharmacological and therapeutic effects of A. cepa were reviewed. Different online databases using keywords such as onion, A. cepa, therapeutic effects, and pharmacological effects until the end of December 2019 were searched for this purpose. Onion has been suggested to be effective in treating a broad range of disorders, including asthma, inflammatory disorders, dysentery, wounds, scars, keloids and pain. In addition, different studies have demonstrated that onion possesses numerous pharmacological properties, including anti-cancer, anti-diabetic and anti-platelet properties as well as the effect on bone, cardiovascular, gastrointestinal, nervous, respiratory, and urogenital systems effects such as anti-osteoporosis, anti-hypertensive, antispasmodic, anti-diarrheal, neuro-protective, anti-asthmatic and diuretic effects. The present review provides detailed the various pharmacological properties of onion and its constituents and possible underlying mechanisms. The results of multiple studies suggested the therapeutic effect of onion on a wide range of disorders.

An exploratory analysis on the toxicity & safety profile of Polyherbal combination of curcumin, quercetin and rutin

Background

Curcumin, quercetin and rutin are flavonoids having strong antioxidant potential, individually used in treatment of numerous ailments. The safety assessment of each of them is already established but no toxicological assessment has been done that would guarantee the safe use of these three flavonoids when used as a polyherbal combination (PHC). The aim of this study to evaluate the possible toxicological effect of polyherbal combination of these three flavonoids in female Swiss albino mice.

Methods

In acute toxicity study, the oral dose of poly herbal combination was administered to four groups stepwise in single dose and general behaviour, adverse effects and mortality were determined up to 14 days and compared to normal group. In sub-acute study, the tested poly herbal combination was administered orally for 28 days to the four experimental groups and their body weight was measured each alternate day from the first day of dosing. On 29th day the final body weight was recorded and euthanized by using thiopentone sodium, blood was collected and later haematological, lipid profile, biochemical parameter was evaluated and compared to normal group.

Result

In acute toxicity study, no abnormal general behaviour, adverse effects were reported. No significant changes were reported in body weight, haematological, lipid profile, biochemical parameter in sub-acute toxicity study. No mortality was reported in both the study. Histopathological examination revealed no alterations in clinical signs or organ weight at any dose.

Conclusion

The result concludes that the oral administration of Polyherbal combination did not produce any significant toxic effect in swiss albino mice. Hence, the Polyherbal combination can be utilized safely for therapeutic use.

The genomic architecture of the sex-determining region and sex-related metabolic variation in Ginkgobiloba

Sex differences and evolutionary differences are critical biological issues. Ginkgo is an ancient lineage of dioecious gymnosperms with special value for studying the mechanism of sex determination in plants. However, the major genetic basic underlying sex chromosomes remains to be uncovered. In this study, we identify the sex-determining region of Ginkgo and locate it to the area from megabases 48 to 75 on chromosome 2. We find that the male sex-determining region of Ginkgo contains more than 200 genes, including four MADS-box genes, demonstrating that the Ginkgo sex determination system is of the XY type. We also find that genetic sex differences result in specialized flavonoid metabolism and regulation in each sex. These findings establish a foundation for revealing the molecular mechanism of sexual dimorphism and promoting the development of the Ginkgo industry.

2', 4'-dihydroxy-3, 4-methylenedioxychalcone Activate Mitochondrial Apoptosis of Ehrlich Ascites Carcinoma Cells

Background:

Development of effective cancer-chemotherapy is the most challenging field due to the toxicity of chemo-agents.

Objective:

As chalcone has been known to have pharmacological applications, here the aim is to synthesized three chalcone derivatives, 2',4'-dihydroxy-3,4-methylenedioxychalcone (C1), 2'-hydroxy- 2,4, 6-trimethoxychalcone (C2) and 2'-hydroxy-4-methylchalcone (C3) and investigate their anti-cancer properties against Ehrlich Ascites Carcinoma (EAC) cell.

Method:

Anticancer properties against EAC cells were studied by examining growth inhibition, MTT assays, tumour-bearing mice survival, tumour weight measurement and haematological profiles. Moreover, apoptosis of EAC cells was investigated by fluorescence microscopy, flowcytometry and DNA fragmentation assays. Expression of apoptosis related genes were studied by reverse transcriptase-PCR (RT-PCR).

Results:

Among the compounds, C1 exhibited highest cell growth inhibition at 200 mg/kg/day (81.71%; P < 0.01). C1 treatment also increased the life span of EAC-bearing mice (82.60%, P < 0.05) with the reduction of tumour burden (<) compared to untreated EAC-bearing mice. In vitro study indicated that C1 killed EAC-cells in a dose-dependent manner and induced mitochondria-mediated apoptotic pathways. In addition, C1 treated cells exhibited increased apoptotic features such as membrane blebbing, chromatin condensation, and nuclear fragmentation after Hoechst 33342 staining. Increased fragmentation of DNA in gel electrophoresis followed by C1 treatment further confirmed apoptosis of EAC cells. EAC cells treated with C1 showed reduced Bcl-2 expression in contrast to notable upregulation of p53 and Bax expression. It implied that C1 could reinstate the expression of pro-apoptotic tumour suppressor and inhibit anti-apoptotic genes.

Conclusions:

Thus, C1 showed significant growth inhibitory properties and induced apoptosis of EAC cells.

Natural Antioxidant and Anti-Inflammatory Compounds in Foodstuff or Medicinal Herbs Inducing Heme Oxygenase-1 Expression

Heme oxygenase-1 (HO-1) is an inducible antioxidant enzyme that catalyzes heme group degradation. Decreased level of HO-1 is correlated with disease progression, and HO-1 induction suppresses development of metabolic and neurological disorders. Natural compounds with antioxidant activities have emerged as a rich source of HO-1 inducers with marginal toxicity. Here we discuss the therapeutic role of HO-1 in obesity, hypertension, atherosclerosis, Parkinson's disease and hepatic fibrosis, and present important signaling pathway components that lead to HO-1 expression. We provide an updated, comprehensive list of natural HO-1 inducers in foodstuff and medicinal herbs categorized by their chemical structures. Based on the continued research in HO-1 signaling pathways and rapid development of their natural inducers, HO-1 may serve as a preventive and therapeutic target for metabolic and neurological disorders.

A Comprehensive Review of Aminochalcones

Chalcones, members of the flavonoid family, display a plethora of interesting biological activities including but not limited to antioxidant, anticancer, antimicrobial, anti-inflammatory, and antiprotozoal activities. The literature cites the synthesis and activity of a range of natural, semisynthetic, and synthetic chalcones. The current review comprehensively covers the literature on amino-substituted chalcones and includes chalcones with amino-groups at various positions on the aromatic rings as well as those with amino-groups containing mono alkylation, dialkylation, alkenylation, acylation, and sulfonylation. The aminochalcones are categorized according to their structure, and the corresponding biological activities are discussed as well. Some compounds showed high potency against cancer cells, microbes, and malaria, whereas others did not. The purpose of this review is to serve as a one-stop location for information on the aminochalcones reported in the literature in recent years.

Physico-Chemical and Phytochemical Characterization of Moroccan Wild Jujube "Zizyphus lotus (L.)" Fruit Crude Extract and Fractions

Wild jujube “Ziziphus lotus (L.) Desf.” belongs to the Rhamnaceae family and is a traditionally herbaceous medicinal plant. It is very common in arid and semi-arid regions and is currently used for its antidiabetic, sedative, analgesic, anti-inflammatory and hypoglycemic activities. The aim of the present work was to characterize the physico-chemical properties and the phytochemical profile of wild jujube sample collected from the Guercif region, in order to determine the polyphenolic compounds and the antioxidant ability Analyses were carried out directly after the harvest for the determination of pH, refractive index, total soluble solid (°Brix), dry matter, sugar/acidity, total sugars, reducing sugars, as well as lipid and protein content. Results showed that the investigated fruit is acidic (pH 4.9 ± 0.23) and rich in sugars (80.2 g/100 g ± 3.81). The GC-MS analysis of the fruit revealed a number of volatile compounds, as many as 97, belonging to different chemical classes. The HPLC-DAD-ESI/MS analysis showed the presence of a total of 20 polyphenolic compounds in both EtOAc and MeOH-water extracts. Among them, p-Hydroxybenzoic acid was the most abundant in the EtOAc extract (185.68 µg/100 mg ± 0.5) whereas Quercetin 3-O-rhamnoside-7-O-glucoside was found in higher amounts in the MeOH-water extract (25.40 µg/100 mg ± 0.5). These components have medical interest, notably for human nutrition, as well as health benefits and therapeutic effects. Therefore, Moroccan jujube “Zizyphus lotus (L.)” fruit may have potential industrial applications for food formulations.

Enzymatic acylation of cyanidin-3-glucoside with fatty acid methyl esters improves stability and antioxidant activity

Cyanidin-3-glucoside is a major anthocyanin in legumes, black rice, and purple potato, and has anti-inflammatory and antioxidant properties. In the present study, the effect of acylation on cyanidin-3-glucoside lipophilicity, stability, and antioxidant capacity was investigated. Cyanidin-3-glucoside was enzymatically acylated through transesterification with fatty acid esters to produce three monoacylated cyanidin-3-glucoside esters, cyanidin-3-(6″-n-octanoyl)-glucoside, cyanidin-3-(6″-lauroyl)-glucoside, and cyanidin-3-(6″-myristoyl)-glucoside. Cyanidin-3-(6″-n-octanoyl)-glucoside had the highest thermostability and photostability of the three cyanidin-3-glucoside esters. While the in vitro antioxidant activity of cyanidin-3-(6″-n-octanoyl)-glucoside was 7.5%-14.3% lower than that of cyanidin-3-glucoside (p < 0.05), its cellular antioxidant activity increased by 33.3% (p < 0.05). Further, while cyanidin-3-(6″-lauroyl)-glucoside had lower stability and in vitro antioxidant activity than that of cyanidin-3-(6″-n-octanoyl)-glucoside, its cellular antioxidant capacity was 125.9% and 69.4% higher than cyanidin-3-glucoside and cyanidin-3-(6″-n-octanoyl)-glucoside, respectively (p < 0.05). This study demonstrated that transesterification can be used to improve the stability and in vivo antioxidant activity of cyanidin-3-glucoside.

Combined Analysis of Transcriptome and Metabolome Reveals the Potential Mechanism of Coloration and Fruit Quality in Yellow and Purple Passiflora edulis Sims

Passion fruit (Passiflora edulis Sims) can be divided into yellow and purple varieties. However, information about coloration and fruit quality between the two varieties is limited. To reveal the underlying mechanism of color formation in this fruit, a combined analysis of the metabolome and transcriptome was conducted in this study. The results showed that most of the evaluated flavonols, anthocyanins, and flavanols were significantly upregulated in purple fruit compared to their levels in yellow fruit. Flavonoid and flavonoid carbonoside accumulation was markedly higher in yellow fruit than in purple fruit. The accumulation of organic acids, phenolic acids, lipids, sugars, and lignans was significantly different in the yellow and purple varieties. These results were consistent with the results from the RNA-Seq profile. This study will enable us to identify genes for targeted genetic engineering to improve the nutritional and market value of passion fruit. In addition, the peel and pulp of passion fruit contained certain health-promoting compounds, highlighting the potential application of passion fruit as a functional food and providing direction for future breeding programs and production.

Crotalaria verrucosa Leaf Extract Mediated Synthesis of Zinc Oxide Nanoparticles: Assessment of Antimicrobial and Anticancer Activity

In this work, we present an ecofriendly, non-hazardous, green synthesis of zinc oxide nanoparticles (ZnO NPs) by leaf extract of Crotalaria verrucosa (C. verrucosa). Total phenolic content, total flavonoid and total protein contents of C. verrucosa were determined. Further, synthesized ZnO NPs was characterized by UV-visible spectroscopy (UV-vis), X-ray diffractometer (XRD), Fourier transform infra-red (FTIR) Spectra, transmission electron microscope (TEM), and Dynamic light scattering (DLS) analysis. UV-vis shows peak at 375 nm which is unique to ZnO NPs. XRD analysis demonstrates the hexagonal phase structures of ZnO NPs. FTIR spectra demonstrates the molecules and bondings associated with the synthesized ZnO NPs and assures the role of phytochemical compounds of C. verrucosa in reduction and capping of ZnO NPs. TEM image exhibits that the prepared ZnO NPs is hexagonal shaped and in size ranged between 16 to 38 nm which is confirmed by DLS. Thermo-gravimetric analysis (TGA) was performed to determine the thermal stability of biosynthesized nanoparticles during calcination. The prepared ZnO NPs showed significant antibacterial potentiality against Gram-positive (S. aureus) and Gram-negative (Proteus vulgaris, Klebsiella pneumoniae, and Escherichia coli) pathogenic bacteria and SEM image shows the generalized mechanism of action in bacterial cell after NPs internalization. In addition, NPs are also found to be effective against the studied cancer cell lines for which cytotoxicity was assessed using MTT assay and results demonstrate highest growth of inhibition at the concentration of 100 µg/mL with IC50 value at 7.07 µg/mL for HeLa and 6.30 µg/mL for DU145 cell lines, in contrast to positive control (C. verrucosa leaf extract) with IC50 of 22.30 µg/mL on HeLa cells and 15.72 µg/mL on DU145 cells. Also, DAPI staining was performed in order to determine the effect on nuclear material due to ZnO NPs treatment in the studied cell lines taking leaf extract as positive control and untreated negative control for comparison. Cell migration assay was evaluated to determine the direct influence of NPs on metastasis that is potential suppression capacity of NPs to tumor cell migration. Outcome of the synthesized ZnO NPs using C. verrucosa shows antimicrobial activity against studied microbes, also cytotoxicity, apoptotic mediated DNA damage and antiproliferative potentiality in the studied carcinoma cells and hence, can be further used in biomedical, pharmaceutical and food processing industries as an effective antimicrobial and anti-cancerous agent.

Pomegranate: Nutraceutical with Promising Benefits on Human Health

Pomegranate is an old plant made up by flowers, roots, fruits and leaves, native to Central Asia and principally cultivated in the Mediterranean and California (although now widespread almost all over the globe). The current use of this precious plant regards not only the exteriority of the fruit (employed also for ornamental purpose) but especially the nutritional and, still potential, health benefits that come out from the various parts composing this one (carpellary membranes, arils, seeds and bark). Indeed, the phytochemical composition of the fruit abounds in compounds (flavonoids, ellagitannins, proanthocyanidins, mineral salts, vitamins, lipids, organic acids) presenting a significant biological and nutraceutical value. For these reasons, pomegranate interest is increased over the years as the object of study for many research groups, particularly in the pharmaceutical sector. Specifically, in-depth studies of its biological and functional properties and the research of new formulations could be applied to a wide spectrum of diseases including neoplastic, cardiovascular, viral, inflammatory, metabolic, microbial, intestinal, reproductive and skin diseases. In this review, considering the increasing scientific and commercial interest of nutraceuticals, we reported an update of the investigations concerning the health-promoting properties of pomegranate and its bioactive compounds against principal human pathologies.

Chalcone Methoxy Derivatives Exhibit Antiproliferative and Proapoptotic Activity on Canine Lymphoma and Leukemia Cells

Chalcones are interesting candidates for anti-cancer drugs due to the ease of their synthesis and their extensive biological activity. The study presents antitumor activity of newly synthesized chalcone analogues with a methoxy group on a panel of canine lymphoma and leukemia cell lines. The antiproliferative effect of the 2'-hydroxychalcone and its methoxylated derivatives was evaluated in MTT assay after 48 h of treatment in different concentrations. The proapoptotic activity was studied by cytometric analysis of cells stained with Annexin V/FITC and propidium iodide and by measure caspases 3/7 and 8 activation. The DNA damage was evaluated by Western blot analysis of phosphorylated histone H2AX. The new compounds had selective antiproliferative activity against the studied cell lines, the most effective were the 2'-hydroxy-2″,5″-dimethoxychalcone and 2'-hydroxy-4',6'-dimethoxychalcone. 2'-Hydroxychalcone and the two most active derivatives induced apoptosis and caspases participation, but some percentage of necrotic cells was also observed. Comparing phosphatidylserine externalization after treatment with the different compounds it was noted that the addition of two methoxy groups increased the proapoptotic potential. The most active compounds triggered DNA damage even in the cell lines resistant to chalcone-induced apoptosis. The results confirmed that the analogues could have anticancer potential in the treatment of canine lymphoma or leukemia.

Optimum Extraction Condition of Clitorea ternatea Flower on Antioxidant Activities, Total Phenolic, Total Flavonoid and Total Anthocyanin Contents

Clitoria ternatea is a herbaceous plant with many health benefits. Extraction is crucial to obtain its bioactive components which contribute to its antioxidant properties. Therefore, this study was conducted to find an optimum extraction condition of C. ternatea flower on total phenolic content (TPC) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging activity) as well as to determine its total flavonoid content (TFC) and anthocyanin content based on the optimum extraction condition generated by Response Surface Methodology (RSM)-Design Expert 7.1.5. TPC, TFC and total anthocyanin of C. ternatea were conducted by Folin Ciocalteu (FC), calorimetric assay and pH differential method, respectively. The ranges of selected independent variables were ethanol concentration (30°C–90% v/v), time (60–120 min) and temperature (30°C–70°C). The optimum extraction condition was obtained at 39.62% v/v ethanol concentration, 90 min and 44.24°C. However, these values were slightly adjusted according to the convenience of equipment to operate in which ethanol concentration was adjusted to 37% v/v, time remain at 90 min and temperature at 45°C. The predicted values of TPC and DPPH radical scavenging activity were 41.60 mg GAE/g dry samples and 68.12% inhibition and were experimentally verified to be 41.17 ± 0.5 mg GAE/g dry samples and 63.53 ± 0.95% inhibition of TPC and DPPH radical scavenging activity respectively. This result has showed RSM can optimise TPC and radical scavenging activity of C. ternatea. Upon the optimum condition, the TFC determined was 187.05 ± 3.18 mg quercetin/g dried sample which was higher than TPC and the total anthocyanin content was 28.60 ± 0.04 mg/L. Hence, the extractable phenolic, flavonoid and anthocyanin compounds indicated that C. ternatea is a good source of natural antioxidant.

Polyphenol-Mediated Autophagy in Cancer: Evidence of In Vitro and In Vivo Studies

One of the hallmarks of cellular transformation is the altered mechanism of cell death. There are three main types of cell death, characterized by different morphological and biochemical features, namely apoptosis (type I), autophagic cell death (type II) and necrosis (type III). Autophagy, or self-eating, is a tightly regulated process involved in stress responses, and it is a lysosomal degradation process. The role of autophagy in cancer is controversial and has been associated with both the induction and the inhibition of tumor growth. Autophagy can exert tumor suppression through the degradation of oncogenic proteins, suppression of inflammation, chronic tissue damage and ultimately by preventing mutations and genetic instability. On the other hand, tumor cells activate autophagy for survival in cellular stress conditions. Thus, autophagy modulation could represent a promising therapeutic strategy for cancer. Several studies have shown that polyphenols, natural compounds found in foods and beverages of plant origin, can efficiently modulate autophagy in several types of cancer. In this review, we summarize the current knowledge on the effects of polyphenols on autophagy, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of polyphenols for envisioning future therapies employing polyphenols as chemoadjuvants.

Flavonoid-sensitized photolysis of chlorothalonil in water

BACKGROUND

Chlorothalonil is a conventional chloroaromatic fungicide and is toxic to many aquatic species. This study was designed to investigate the effects of six flavonoids on the photolysis of chlorothalonil under sunlight and artificial light.

RESULTS

Flavonoids sensitized the photolysis of chlorothalonil under sunlight and artificial light by 6.7-18.3 and 2.4-7.5 times, respectively, in comparison with a flavonoid-free control. Photosensitization effect of each of the six flavonoids was greater under sunlight irradiation than under high-pressure mercury lamp irradiation. Cyanidin showed greater photosensitization effects than luteolin, galangin, quercetin, morin and kaempferol. Chlorothalonil underwent photo-reductive dechlorination and no hydrolysis product was formed in the presence of flavonoids. Hydroxyl and hydrogen radicals were detected in the absence and presence of cyanidin, respectively, under light irradiation.

CONCLUSION

The photosensitization effect of flavonoids on chlorothalonil photolysis is apparently related to flavonoid structure and might be due to their hydrogen donation capacity. These results highlight benefit of using flavonoids to manage aquatic pollution and reduce aquatic toxicity, and have great relevance in predicting the degradation kinetics and biological impacts of chlorothalonil in surface water. © 2020 Society of Chemical Industry.

Coumarin-chalcone hybrids targeting insulin receptor: Design, synthesis, anti-diabetic activity, and molecular docking

Four series of thirteen new coumarin-chalcone hybrids (DPCU 1-13, DPCT 1-13, DCCU 1-13 and DCCT 1-13) were designed and synthesized using Biginelli synthesis, Pechmann condensation, Acetylation, and Claisen-Schmidt reactions. Synthesized compounds were tested for insulin receptor in silico docking studies (PDB ID: 1IR3); DCCU 13 and DCCT 13 derivatives received the lowest docking score; Streptozocin (STZ) and Nicotinamide (NA) induced type II diabetes was tested for their anti-diabetic activity in rats. In vivo tests suggested that fasting blood glucose levels of animals treated with DCCU 13 (30 mg/kg body weight) and DCCT 13 (30 mg/kg body weight) were significantly and moderately suppressed, respectively, relative to fasting blood glucose levels of diabetic control animals. Similarly, therapy with DCCU 13 and DCCT 13 attenuated oxidative stress parameters such as lipid peroxidation (MDA), superoxide dismutase (SOD) and increased the glutathione (GSH) in the liver and pancreas in a dose-dependent manner. In comparison, therapy with DCCU 13 (30 mg/kg body weight) mitigated alterations in the histological architecture of the liver and pancreatic tissue. These results indicated that the hybrids DUUC 13 and DCCT 13 at 30 mg/kg had an anti-hyperglycemic and antioxidant impact on STZ + NA mediated type II diabetes in rats. Further detailed work could be required to determine the precise mode of action of the anti-diabetic behavior of hybrids.

Isorhamnetin induces the paraptotic cell death through ROS and the ERK/MAPK pathway in OSCC cells

OBJECTIVE

There were rarely investigations on the effects and molecular mechanisms of oral squamous cell carcinoma (OSCC) cells when treated with isorhamnetin. This article assesses the anti-cancer effect of isorhamnetin.

METHODS AND MATERIALS

Oral squamous cell carcinoma cells were treated with or without isorhamnetin. Cell proliferation, cell cycle arrest, cell migration, cell death, and the related signaling pathways were evaluated.

RESULTS

The results revealed that cell proliferation was inhibited in a dose- and time-dependent manner, which was confirmed by diminished cell viability and revealed by decreased in the number of cell colonies. In addition, the cell cycle arrested in the G2/M phase, and the protein levels of cyclin B1 and CDC2 were suppressed. Moreover, the cell migration was inhibited, and the protein levels of related proteins were modulated. Furthermore, it could be observed that abundant cytoplasmic vacuoles existed which that were derived from mitochondria and the endoplasmic reticulum. It was confirmed that cell death did not result from apoptosis and may have which may be apt to paraptosis. Isorhamnetin was observed to upregulate phosphorylated ERK cascades and increase intracellular reactive oxygen species levels.

CONCLUSIONS

Our study suggested that the anti-cancer effect of isorhamnetin might trigger paraptosis, which may indicate a new therapeutic approach to OSCC.

3D-QSAR Study of the Chalcone Derivatives as Anticancer Agents

For their biological properties and particularly for their anticancer activities, chalcones are widely studied. In this work, we have submitted diverse sets of chalcone derivatives to the 3D-QSAR (3-dimensional quantitative structural-activity relationship) to study their anticancer activities against HTC116 (human colon cancer), relying on the 3-dimensional descriptors: steric and electrostatic descriptors for the CoMFA (comparative molecular field analysis) method and steric, electrostatic, hydrophobic, H-bond donor, and H-bond acceptor descriptors for the CoMSIA method. CoMFA as well as the CoMSIA model have encouraging values of the cross-validation coefficient (Q2) of 0.608 and 0.806 and conventional correlation coefficient (R2) of 0.960 and 0.934, respectively. Furthermore, values of R2test have been obtained as 0.75 and 0.90, respectively. Besides, y-randomization test was also performed to validate our 3D-QSAR models. Based on these satisfactory results, ten new compounds have been designed and predicted by in silico ADMET method. This study could expand the understanding of chalcone derivatives as anticancer agents and would be of great help in lead optimization for early drug discovery of highly potent anticancer activity.

Protective Role of <i>Juniperus phoenicea</i> L. Leaves Extract against Gamma-irradiation-induced Oxidative Stress

BACKGROUND AND OBJECTIVE

Radiation exposure can cause several harmful effects in biological systems due to free radical production. Several antioxidants have been tested as potential hepatoprotective agents against ionizing radiation as they lower oxidative stress in normal cells induced by Reactive Oxygen Species (ROS). The present study was conducted to evaluate the possible ameliorative effects of Juniperus phoenicea L.

MATERIALS AND METHODS

Aqueous leaves extract on different biochemical and histopathological parameters against whole body gamma-irradiation-induced oxidative stress, organ dysfunction and metabolic disturbances in experimental Swiss Albino rats. After a single dose of gamma-radiation (6 Gy), there was a significant reduction in albumin, total protein and globulin levels and a significant increase in the liver enzymes (ALT, AST, ALP and GGT) and lipid profile parameters (cholesterol, triglyceride, HDL-cholesterol and LDL-cholesterol) in gamma-irradiated rats unlike in normal controls.

RESULTS

The gamma-irradiated rats pre-treated with J. phoenicea leaf extracts, however, showed a significant increase in albumin, total protein and globulin levels and a significant reduction in liver enzymes and lipid profile parameters as opposed to the untreated ones. The gamma-irradiated rats showed toxic changes in the liver, whereas, the rats pre-treated with J. phoenicea leaves extract demonstrated a protective effect. Additionally, gamma- irradiation caused myocardial degenerative changes, interstitial edema between muscle fibers, necrosis and inflammatory cells infiltration and fibrotic and cellular damages to the heart, but J. phoenicea leaves extract were found to ameliorate the gamma-irradiation-induced changes in the heart.

CONCLUSION

The results suggested that treatment with J. phoenicea leaves extract is possibly safe and can ameliorate gamma-irradiation-induced oxidative damage and tissue injury in rats. The leaves of J. phoenicea could serve as a potential source of therapeutic antioxidants.

A small library of chalcones induce liver cancer cell death through Akt phosphorylation inhibition

Hepatocellular carcinoma (HCC) ranks as the fifth most common and the second deadliest cancer worldwide. HCC is extremely resistant to the conventional chemotherapeutics. Hence, it is vital to develop new treatment options. Chalcones were previously shown to have anticancer activities in other cancer types. In this study, 11 chalcones along with quercetin, papaverin, catechin, Sorafenib and 5FU were analyzed for their bioactivities on 6 HCC cell lines and on dental pulp stem cells (DPSC) which differentiates into hepatocytes, and is used as a model for untransformed control cells. 3 of the chalcones (1, 9 and 11) were selected for further investigation due to their high cytotoxicity against liver cancer cells and compared to the other clinically established compounds. Chalcones did not show significant bioactivity (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\hbox {IC}_{50}>20\upmu \hbox {M}$$\end{document}IC50>20μM) on dental pulp stem cells. Cell cycle analysis revealed that these 3 chalcone-molecules induced SubG1/G1 arrest. Akt protein phosphorylation was inhibited by these molecules in PTEN deficient, drug resistant, mesenchymal like Mahlavu cells leading to the activation of p21 and the inhibition of NF\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \kappa $$\end{document}κB-p65 transcription factor. Hence the chalcones induced apoptotic cell death pathway through NF\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \kappa $$\end{document}κB-p65 inhibition. On the other hand, these molecules triggered p21 dependent activation of Rb protein and thereby inhibition of cell cycle and cell growth in liver cancer cells. Involvement of PI3K/Akt pathway hyperactivation was previously described in survival of liver cancer cells as carcinogenic event. Therefore, our results indicated that these chalcones can be considered as candidates for liver cancer therapeutics particularly when PI3K/Akt pathway involved in tumor development.

Quercitrin, the Main Compound in Wikstroemia indica, Mitigates Skin Lesions in a Mouse Model of 2,4-Dinitrochlorobenzene-Induced Contact Hypersensitivity

Hapten-induced contact hypersensitivity (CHS) is widely utilized to induce immune activation in animal models of allergic contact dermatitis. Our previous findings suggested that the 95% EtOH extract of Wikstroemia indica (L.) C. A. Mey. has antiallergic and anti-inflammatory effects in DNCB-treated CHS SKH-1 hairless mice. The aim of this study was to evaluate the protective effects of compounds isolated from the EtOAc fraction of W. indica in RBL-2H3 cells and 2,4-dinitrochlorobenzene- (DNCB-) induced CHS mice. Of eight compounds in W. indica, that is, umbelliferone, daphnoretin, wikstrocoumarin, (+)-syringaresinol, tricin, (+)-lariciresinol, erythro-guaiacylglycerol-β-coniferyl ether, and quercitrin, quercitrin exhibited the most antiallergic activity against antigen-induced β-hexosaminidase release and IL-4 mRNA expression, which are markers of degranulation in RBL-2H3 cells. After a 7-sensitizing period, 14 days of DNCB treatment with or without topical pimecrolimus (1%) or quercitrin (0.5%) treatment, quercitrin was found to suppress DNCB-induced increases in serum IL-4 and IgE concentrations and transepidermal water loss. These results indicate that quercitrin has therapeutic potential for treatment of allergies and allergy-related contact dermatitis.

Leptin and Nutrition in Gestational Diabetes

Leptin is highly expressed in the placenta, mainly by trophoblastic cells, where it has an important autocrine trophic effect. Moreover, increased leptin levels are found in the most frequent pathology of pregnancy: gestational diabetes, where leptin may mediate the increased size of the placenta and the fetus, which becomes macrosomic. In fact, leptin mediates the increased protein synthesis, as observed in trophoblasts from gestational diabetic subjects. In addition, leptin seems to facilitate nutrients transport to the fetus in gestational diabetes by increasing the expression of the glycerol transporter aquaporin-9. The high plasma leptin levels found in gestational diabetes may be potentiated by leptin resistance at a central level, and obesity-associated inflammation plays a role in this leptin resistance. Therefore, the importance of anti-inflammatory nutrients to modify the pathology of pregnancy is clear. In fact, nutritional intervention is the first-line approach for the treatment of gestational diabetes mellitus. However, more nutritional intervention studies with nutraceuticals, such as polyphenols or polyunsaturated fatty acids, or nutritional supplementation with micronutrients or probiotics in pregnant women, are needed in order to achieve a high level of evidence. In this context, the Mediterranean diet has been recently found to reduce the risk of gestational diabetes in a multicenter randomized trial. This review will focus on the impact of maternal obesity on placental inflammation and nutrients transport, considering the mechanisms by which leptin may influence maternal and fetal health in this setting, as well as its role in pregnancy pathologies.

Synthesis and Anti-Saprolegnia Activity of New 2',4'-Dihydroxydihydrochalcone Derivatives

In the present study, seven 2',4'-dihydroxydihydrochalcone derivatives (compounds 3-9) were synthesized and their capacity as anti-Saprolegnia agents were evaluated against Saprolegnia parasitica, S. australis, S. diclina. Derivative 9 showed the best activity against the different strains, with minimum inhibitory concentration (MIC) and minimum oomyceticidal concentration (MOC) values between 100-175 μg/mL and 100-200 μg/mL, respectively, compared with bronopol and fluconazole as positive controls. In addition, compound 9 caused damage and disintegration cell membrane of all Saprolegnia strains over the action of commercial controls.

Antinociceptive and anti-inflammatory effect of Poincianella pyramidalis (Tul.) L.P. Queiroz

ETHNOPHARMACOLOGY RELEVANCE

Poncianella pyramidalis (Leguminosae) is a Caatinga plant used in folk medicine because of its pharmacological properties, which include anti-inflammatory action. However, chemical compounds responsible for this effect have not yet been identified.

AIM OF THE STUDY

This study aimed to evaluate the antioxidant, antinociceptive and anti-inflammatory effects of the ethyl acetate fraction from the inner bark of P. pyramidalis.

MATERIAL AND METHODS

Total phenol content (TP) was estimated using the Folin-Ciocalteu reagent, while in vitro antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay. Chemical identification was done using LC-PDA/MS and LC-ESI/MS/MS. In vivo antinociceptive and anti-inflammatory properties were investigated using formalin, mechanical hypernociception and carrageenan-induced pleurisy assays in mice.

RESULTS

TP was 525.08 ± 17.49 μg mg^-1 gallic acid equivalent. The ethyl acetate fraction (EAF) inhibited 87.76% of the DPPH radical with an EC₅₀ of 22.94 μg mL^-1 and Antioxidant Activity Index of 1.74. LC-PDA/MS and LC-ESI/MS/MS identified 15 compounds that are mostly derived from gallic and ellagic acids. Regarding in vivo antinociceptive and anti-inflammatory activity, EAF (100 mg kg-1) significantly reduced the nociceptive response in the second phase of the formalin assay by 50% (p < 0.01) compared with the control group. In the hypernociception test, a significant (p < 0.001) anti-hyperalgesic effect of EAF (100 mg kg-1) was observed up to the third hour of evaluation (p < 0.001). In the carrageenan assay, EAF (100 mg kg-1) was shown to inhibit protein extravasation, increase total leukocytes and neutrophils, and inhibit mononuclear cells.

CONCLUSION

These results demonstrate EAF from the inner bark of P. pyramidalis has strong in vitro antioxidant effect as well as in vivo antinociceptive and anti-inflammatory activities, which may be attributed to the bark being rich in phenolic compounds derived from gallic acid.

Molecular Docking, Synthesis and anti-HIV-1 Protease Activity of Novel Chalcones

Background:

Since the beginning of the HIV/AIDS epidemic, 75 million people have been infected with the HIV and about 32 million people have died of AIDS. Investigation of the molecular mechanisms critical to the HIV replication cycle led to the identification of potential drug targets for AIDS therapy. One of the most important discoveries is HIV-1 protease, an enzyme that plays an essential role in the replication cycle of HIV.

Objective:

The aim of the present study is to synthesize and investigate anti-HIV-1 protease activity of some chalcone derivatives with the hope of discovering new lead structure devoid drug resistance.

Methods:

20 structurally similar chalcone derivatives were synthesized and their physico-chemical characterization was performed. Binding of chalcones to HIV-1 protease was investigated by fluorimetric assay. Molecular docking studies were conducted to understand the interactions.

Results:

The obtained results revealed that all compounds showed anti-HIV-1 protease activity. Compound C1 showed the highest inhibitory activity with an IC50 value of 0.001 μM, which is comparable with commercial product Darunavir.

Conclusion:

It is difficult to provide general principles of inhibitor design. Structural properties of the compounds are not the only consideration; ease of chemical synthesis, low molecular weight, bioavailability, and stability are also of crucial importance. Compared to commercial products the main advantage of compound C1 is the ease of chemical synthesis and low molecular weight. Furthermore, compound C1 has a structure that is different to peptidomimetics, which could contribute to its stability and bioavailability.

Screening of chalcone analogs with anti-depressant, anti-inflammatory, analgesic, and COX-2-inhibiting effects

A group of 2-methyl-4-phenylquinoline-chalcone analogs (2a-2x) was synthesized and investigated for anti-depressant, anti-inflammatory, and analgesic effects as cyclooxygenase-2 inhibitors. Pharmacological experiments identified 24 analogs that exhibited anti-depressant, anti-inflammatory, and analgesic activities. In particular, compounds 2c, 2k, and 2w markedly shortened immobility times and exhibited the most anti-depressant activity. In addition, the mechanisms of action of the analogs 2c, 2k, and 2w were likely related to increased serotonin levels in the central nervous system. Compounds 2c, 2k, and 2w displayed reasonable cyclooxygenase-2 inhibitory effects (IC₅₀ values from 0.21 to 0.29 µmol/L) similar to celecoxib (IC₅₀: 0.19 µmol/L) in vitro. A molecular docking study of compound 2k also was conducted.

Gastroprotective effects of Erythrina speciosa (Fabaceae) leaves cultivated in Egypt against ethanol-induced gastric ulcer in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Members of the genus Erythrina have been traditionally used in the treatment of various ailments such as inflammation and gastrointestinal disorders. Erythrina speciosa (Fabaceae) is a spiny, deciduous shrub or small tree native to Southern America in Brazil. It is cultivated in Africa and Asia. The traditional usage of E. speciosa indicated its antibacterial, analgesic, and anti-inflammatory activities.

AIM OF THE STUDY

Evaluation of the phytochemical constituents, gastroprotective effects and possible mechanism of action of the ethyl acetate fraction obtained from the methanol extract of E. speciosa leaves (ESLE).

MATERIALS AND METHODS

Chemical characterization of ESLE was done using high performance liquid chromatography coupled to mass spectrometry (HPLC-MS). The gastroprotective activity of ESLE was evaluated using ethanol-induced gastric-ulcer model in rats. Rats were pre-treated with ESLE 25, 50 and 100 mg/kg 1 h before the administration of absolute ethanol. Histological analysis, mucin content, and total acidity were evaluated. The possible mechanism of action of ESLE was studied through the examination of oxidative stress and inflammatory markers, PGE2, and NF-κB, iNOS, COX-2, and HSP-70 immunoexpression. In vitro, anti-Helicobacter pylori activity of ESLE was also studied using micro-well dilution method.

RESULTS

Fourteen compounds were tentatively identified including alkaloids, flavonoids, and saponins. ESLE exerted a powerful gastroprotective effect. The pre-treatment with ESLE at different doses resulted in a significant reduction in gastric lesions and significant elevation in the mucin production. These effects could be partially mediated by the potent anti-inflammatory activity of ESLE as evidenced by the significant reduction in the immunoexpression of NF-κB, COX-2, iNOS and the reduction in the pro-inflammatory marker, TNF-α. ESLE counteracted the ethanol-induced oxidative stress by increasing the levels of depleted GSH and catalase as well as significantly attenuating the ethanol-induced lipid peroxidation tissue levels. In addition, ESLE exhibited in vitro antibacterial activity against H. pylori.

CONCLUSIONS

The chemical constituents of ESLE strongly support its potent gastroprotective effect suggesting its future potential application in the management of gastric ulcer by eliminating its symptoms and causes including H. pylori.

Ex vivo efficacy of selective chalcone derivatives on reference strains and field isolates of Plasmodium falciparum

The extension of Plasmodium falciparum resistance to existing antimalarial drugs is worrying. Faced with this problem, the search for new and effective molecules is necessary. In this context, six chalcone derivatives (B1, B11, B14, B17, SCA02 and SCA03) were tested on field isolates and then reference strains to evaluate their antiplasmodial activity by using the Rieckmann semi-microtest, recommended by WHO, for in vitro and ex vivo activity tests. Compounds B14 and B17 exhibited promising antiplasmodial activities (IC_50s: 14.41-16.40 μM) regardless of the type of isolate. Compounds B1, B11, SCA02 and SCA03 showed a moderate inhibition of field isolates (IC_50S: 25.63-48.29 μM) and very good activity against reference strains (IC50s: 3.82-10.03 μM). Therefore, more structural modulations should improve their efficiency and make these molecules very good candidates for future effective antimalarial drugs.

Molecular docking analysis of flavonoid compounds with HIV-1 Reverse transcriptase for the identification of potential effective inhibitors

It is of interest to elucidate the binding mode analysis of 18 sulphonated flavones in the non nucleoside inhibitory binding pocket of the HIV-1 reverse transcriptase (PDB ID: 1RTD). We further compared them with the known Non Nucleosidic Reverse Transcriptase Inhibitors (NNRTI) drug molecules such as delaviridine, nevirapine and etravirine. Molecular docking studies of sulphonated flavones were performed in the binding pocket of reverse transcriptase using the PatchDock server. The flavones have different binding energies with RT and the atomic contact energy (ACE) value of sulfonated flavones range from-389 to-231 Kcal/mol while docking of the commercialized NNRTI showed the ACE value range from -486 to -224 Kcal/mol. This shows that most sulfonated flavones have ACE similar to the known NNRTI. Thus, seven compounds (FS-6, FS-7, FS-8, FS-9, FS-14, FS-15, FS-17) were reported as potent, selective, orally bio available, and nontoxic lead based on ADMET screening and effective binding analysis in the active site of the reverse transcriptase (PDB ID: 1RTD) for further consideration. We further document that compounds (FS-1, FS-10, FS-4 and FS-12) have unfavorable binding features to be considered as leads.

2-Arylidene-1-indandiones as Pleiotropic Agents with Antioxidant and Inhibitory Enzymes Activities

Indandiones are a relatively new group of compounds presenting a wide range of biological activities. The synthesis of these compounds was performed via a Knoevenagel reaction between an aldehyde and 1,3-indandione and were obtained with a yield up to 54%. IR, 1H-Nucleic Magnetic Resonance (NMR), 13C-NMR, LC/MS ESI+ and elemental analysis were used for the confirmation of the structures of the novel derivatives. Lipophilicity values of compounds were calculated theoretically and experimentally by reversed chromatography method as values RM. The novel derivatives were studied through in vitro and in vivo experiments for their activity as anti-inflammatory and antioxidant agents and as inhibitors of lipoxygenase, trypsin, and thrombin. The inhibition of the carrageenin-induced paw edema (CPE) was also determined for representative structures. In the above series of experiments, we find that all the compounds showed moderate to satisfying interaction with the stable DPPH free radical in relation to the concentration and the time 2-arylidene-1-indandione (10) was the strongest. We observed moderate or very low antioxidant activities for selected compounds in the decolorization assay with ABTS+•. Most of the compounds showed high anti-lipid peroxidation of linoleic acid induced by AAPH.2-arylidene-1-indandione (7) showed a strongly inhibited soybean LOX. Only 2-arylidene-1-indandione (3) showed moderate scavenging activity of superoxide anion, whereas 2-arylidene-1-indandione (8) and 2-arylidene-1-indandione (9) showed very strong inhibition on proteolysis. 2-arylidene-1-indandione (8) highly inhibited serine protease thrombin. 2-arylidene-1-indandiones (7, 8 and 9) can be used as lead multifunctional molecules. The compounds were active for the inhibition of the CPE (30-57%) with 2-arylidene-1-indandione (1) being the most potent (57%). According to the predicted results a great number of the derivatives can cross the Blood-Brain Barrier (BBB), act in CNS and easily transported, diffused, and absorbed. Efforts are conducted a) to correlate quantitatively the in vitro/in vivo results with the most important physicochemical properties of the structural components of the molecules and b) to clarify the correlation of actions among them to propose a possible mechanism of action. Hydration energy as EHYDR and highest occupied molecular orbital (HOMO) better describe their antioxidant profile whereas the lipophilicity as RM values governs the in vivo anti-inflammatory activity. Docking studies are performed and showed that soybean LOX oxidation was prevented by blocking into the hydrophobic domain the substrates to the active site.

The detection of the precursors of the photorearranged products of 3-hydroxyflavones in selected solvents from UV-visible spectra in situ

Mechanistic studies relating to the photochemistry of 3-hydroxy-2-phenyl-4H-chromen-4-one (3HF) and 6-chloro-3-hydroxy-2-phenyl-4H-chromen-4-one (Cl-3HF) have been reinvestigated in selected solvents. The UV-visible spectra of the photoproduct(s) of 3HF and Cl-3HF have been computed in situ via subtracting the spectra of unreacted substrates, with acetonitrile (ACN) and methanol (MeOH) as solvents. These spectra turn out to be different from the spectra of the corresponding isolated photoproducts: 3-hydroxy-3-phenyl-indan-1,2-dione and 6-chloro-3-hydroxy-3-phenyl-indan-1,2-dione (referred to as dione ). Analyses of the photoproduct(s) via GC-MS show the formation of a single detectable product, i.e., the corresponding dione. On the basis of some experimental observations, it is proposed that the primary photoproduct in situ is 2,3-epoxy-2-hydroxy-1-indanone (referred to as epoxide) instead of dione as reported in previous years. Earlier, epoxide has been proposed to be the intermediate in the mechanism for the formation of dione. This is the first report where the formation of epoxide has been directly detected in the selected solvents. On the other hand, both dione and epoxide (2 : 1) are shown to be formed with MeOH as solvent. The second important finding is that epoxide and dione interconvert in the dark, depending upon the environment. With ACN as solvent, pure dione in the dark is kinetically and partially converted to epoxide. With MeOH as solvent, epoxide is instantly and partially converted to dione until both are in equilibrium. However, a solution of dione in MeOH remains stable in the dark. The photoformation of epoxide is quantitative with ACN as solvent and it is sufficiently stable. It has been further observed that epoxide solutions of 3HF and Cl-3HF in ACN are quantitatively converted into 3-phenylisobenzofuran-1(3H)-one and 6-chloro-3-phenylisobenzofuran-1(3H)-one, i.e., the corresponding phthalides, through the loss of CO when kept in the dark for some days. A mechanism has been proposed where epoxide has been shown to give dione and/or phthalide via selective C-O or C-C bond cleavage in the oxiranyl ring, respectively. The selection of this cleavage depends mainly on the solvent system and the substituents in the parent flavones.

Proximate composition, phytochemicals, minerals and antioxidant activities of Vigna mungo L.seed coat

Vigna mungo L. seed coat is an agro by-product, available in substantial quantity, with no clear evidence to prove its economic importance. In the present study, the phytochemicals, proximate content, minerals and in vitro antioxidant activities of aqueous (AE), ethanol (EE) and 80% ethanolic extract (80% EE) of Vigna mungo L. seed coat were determined. The total carbohydrate, total protein, crude fibre, ash and moisture content of the seed coat were found to be 27.52±2.71%, 10.07±0.92%, 48.67±1.96%, 4.87±0.29% and 11.03±0.49% respectively. The content of total phenolics and flavonoids were significantly higher in 80% EE than other extracts. The mineral composition showed that seed coat was rich in calcium, sodium, potassium, magnesium, iron, copper, zinc and manganese. The higher antioxidant potential was shown by 80% EE in DPPH and SOD assay whereas AE shows more scavenging activity in H2O2 assay. So it can be used as neutraceuticals in food supplements.