Flavonoid Derivatives Research Articles

Pharmacognostic, characterization, physio-chemical scrutinizes, and biological attributes of <i>Goniothalamus wightii</i>

To evaluate the quality control parameters of <i>Goniothalamus wightii</i> leaves, which are used for traditional medicine. The leaves extracts were characterized and to evaluate the phytochemical composition, antibacterial, antibiofilm and antioxidant activities. The macroscopic studies of the leaves are simply arranged, green color and dicot plant. The physico-chemical values are the presence of foreign matter, loss on drying, moisture and tannin content, no swelling and foaming capacity. Total ash, acid-insoluble ash, water soluble ash, and sulphated ash are the ash values; extractive values are examined in various organic solvents with visualized UV to exhibit various color variations. The proximate compositions were fiber, soluble and insoluble fiber, carbohydrates, and lipid content presence at g/100g. The quantitative phytoconstituents presence of hexane, ethyl acetate and methanol extracts such as were resolved in sequential extraction with hexane, chloroform, ethyl acetate, and methanol bands were separated. The FT-IR spectrum resembles the aliphatic and aromatic amines, and the LC-MS were identified by phenolic and flavonoids derivatives, steroids, lignin’s. The compounds based the antioxidant activities were 50-80% inhibition against the free radicals and antibacterial, antibiofilm activities were strongly killed the pathogens (<i>E. coli</i>, <i>E. faecalis</i>). In concluded that the pharmacognostic standardization is the first report in these species. The extracts of <i>G. wightiii</i> have potential antioxidant, antibacterial and antibiofilm effects, which could lead to pharmaceutical and industrial applications.

Synthesis of new non-natural L-glycosidic flavonoid derivatives and their evaluation as inhibitors of Trypanosoma cruzi ecto-nucleoside triphosphate diphosphohydrolase 1 (TcNTPDase1).

Trypanosoma cruzi is the pathogen of Chagas disease, a neglected tropical disease that affects more than 6 million people worldwide. There are no vaccines to prevent infection, and the therapeutic arsenal is very minimal and toxic. The unique E-NTPDase of T. cruzi (TcNTPDase1) plays essential roles in adhesion and infection and is a virulence factor. Quercetin is a flavonoid with antimicrobial, antiviral, and antitumor activities. Its potential as a partial inhibitor of NTPDases has also been demonstrated. In this work, we synthesized the non-natural L-glycoside derivatives of quercetin and evaluated them as inhibitors of recombinant TcNTPDase1 (rTcNTPDase1). These compounds, and quercetin and miquelianin, a natural quercetin derivative, were also tested. Compound 16 showed the most significant inhibitory effect (94%). Quercetin, miquelianin, and compound 14 showed inhibition close to 50%. We thoroughly investigated the inhibitory effect of 16. Our data suggested a competitive inhibition with a Ki of 8.39 μM (± 0.90). To better understand the interaction of compound 16 and rTcNTPDase1, we performed molecular dynamics simulations of the enzyme and docking analyses with the compounds. Our predictions show that compound 16 binds to the enzyme's catalytic site and interacts with important residues for NTPDase activity. As an inhibitor of a critical T. cruzi enzyme, (16) could be helpful as a starting point in the developing of a future treatment for Chagas disease. Furthermore, the discovery of (16) as an inhibitor of TcNTPDase1 may open new avenues in the study and development of new inhibitors of E-NTPDases.

A sulfonamide chalcone inhibited dengue virus with a potential target at the SAM-binding site of viral methyltransferase.

Dengue infection is a global health problem as climate change facilitates the spread of mosquito vectors. Infected patients could progress to severe plasma leakage and hemorrhagic shock, where current standard treatment remains supportive. Previous reports suggested that several flavonoid derivatives inhibited mosquito-borne flaviviruses. This work aimed to explore sulfonamide chalcone derivatives as dengue inhibitors and to identify molecular targets. We initially screened 27 sulfonamide chalcones using cell-based antiviral and cytotoxic screenings. Two potential compounds, SC22 and SC27, were identified with DENV1-4 EC50s in the range of 0.71–0.94 and 3.15–4.46 μM, and CC50s at 14.63 and 31.02 μM, respectively. The compounds did not show any elevation in ALT or Cr in C57BL/6 mice on the 1st, 3rd, and 7th days after being administered intraperitoneally with 50 mg/kg SC22 or SC27 in a single dose. Moreover, the SAM-binding site of NS5 methyltransferase was a potential target of SC27 identified by computational and enzyme-based assays. The main target of SC22 was in a late stage of viral replication, but the exact target molecule had yet to be identified. In summary, a sulfonamide chalcone, SC27, was a potential DENV inhibitor that targeted viral methyltransferase. Further investigation should be the study of the structure-activity relationship of SC27 derivatives for higher potency and lower toxicity.

Selected flavonoids exhibit antibiofilm and antibacterial effects against Vibrio by disrupting membrane integrity, virulence and metabolic activities

Vibrio parahaemolyticus is a high-risk foodborne pathogen associated with raw or undercooked seafoods and its biofilm forming potential has become a threat to food safety and economic values. Hence, this study aims to examine the antibacterial and antibiofilm activities as well as virulence inhibitory effects of selected flavonoids against V. parahaemolyticus. Out of the sixteen flavonoid derivatives, 6-aminoflavone (6-AF), 3,2-dihydroxyflavone (3,2-DHF) and 2,2-dihydroxy-4-methoxybenzophenone (DHMB) were found as active biofilm inhibitors. 3,2-DHF and DHMB had minimum inhibitory concentrations of 20 and 50 μg/mL respectively against Vibrio planktonic cells and displayed superior antibacterial activities to standard controls. Also, they disrupted preformed biofilms and suppressed virulence properties including motilities, cell hydrophobicity and aggregation. They impaired iron acquisition mechanism and hemolysin production at sub-MICs as supported by transcriptomic studies. Interestingly, the flavonoids interfered with the metabolic activity, cell division and membrane permeability to exert antibiofilm and antibacterial activities. 6-AF and 3,2-DHF were non-toxic in the C. elegans model and showed excellent capacity to protect shrimps from biodeterioration. Furthermore, the flavonoids inhibited biofilm formation by V. harveyi, Staphylococcus aureus and Salmonella typhimurium and the mixed-species biofilm with Vibrio. This study discovered flavonoid derivatives, especially 3,2-DHF as potential bioactive compounds capable of offering protection from risks associated with biofilm formation by V. parahaemolyticus and other food pathogens.

A Novel Natural Derivative GL-V9 Inducing Mitotic Catastrophe and Displaying a Synergistic Anti-Tumor Effect with EZH2 Inhibitor in Acute Myeloid Leukemia

Background GL-V9 is a flavonoid derivative from the natural product wogonin with elegant anti-tumor activity, while the effect of GL-V9 in acute leukemia has no report. Enhancer of zeste homolog 2 (EZH2) catalyzes trimethylation on the K27 residue of histone H3 (H3K27Me3), which facilitates non-homologous DNA end joining (NHEJ). EZH2 inhibitor could induce chromatin decondensation and promote the sensitivity of tumor cells towards DNA damage drugs. In the present study, we evaluated the anti-leukemia activity of GL-V9 and its synergy with EZH2 inhibitor DZNeP in acute myeloid leukemia (AML). Methods Cell proliferation and cytotoxicity were measured by Cell Counting Kit-8(CCK-8) in U937, THP-1, and MV4-11 AML cells. RNA-seq was performed in U937 cells treated with 2μM DZNeP, MV4-11 cells treated with 4μM GL-V9, and vehicle for 48 hours. The clone formation rate was measured by a plate clone formation assay. Cell cycle and apoptosis were measured by flow cytometry analysis. Morphology examination was conducted with Fluorescence (IF) microscopy . Expression of target genes was detected by western blot and RT-qPCR. Results GL-V9 had a dose-/time-dependent effect on cell viability with IC50 at 3-4μM in U937 and THP-1 cells (Fig.1A); it also significantly induced the G2/M arrest and apoptosis of the cells (Fig.1B, C). IF staining showed GL-V9 triggers micro-, multi-nucleation, and cytoskeleton abnormalities, the feature of mitotic catastrophe in U937 cells 4hrs after the treatment (Fig1.D). These data indicated that GL-V9 exerts the anti-leukemia effect by inducing mitotic catastrophe. We further analyzed the whole genome transcriptome upon GL-V9 treatment in U937 cells, and GSEA analysis of the differentially expressed genes (DEGs) showed that GL-V9 treatment negatively correlated with genes involved in sister chromatid separation, microtubule cytoskeleton organization, DNA double-strand break repair, mismatch repair, and cell cycle checkpoint signaling (Fig1.E). These data revealed that GL-V9 may induce DNA damage-mediated mitotic catastrophe in the AML cells. H3K27me3 and EZH2 play an important role in the early DNA damage response. We thus carried out the combination therapy of EZH2 inhibitor DZNeP with GL-V9. Results showed that co-treatment of GL-V9 with DZNeP exerted synergistic effects on reduced cell viability and clone formation versus single-drug in U937 and MV4-11 cells (Fig2.AB). DZNeP induced G0/G1 arrest; and GL-V9 induced G2/M arrest; whereas the combination significantly decreased the number of cells in the S-phase (Fig2.C). Also, the percentage of the apoptotic cells significantly increased upon the GL-V9+DZNeP treatment versus the controls in the cells (Fig2.D) as well as in ASXL1 mutant AML-M5 and AML-M2 primary cells (Fig2.E). Consistently, the combination significantly induced the expression changes of cell cycle regulator CCNE2 and p21, and dramatically up-regulated apoptotic effectors PARP, Caspase-3, and DNA damage marker γH2AX versus single-drug (Fig2.F). Furthermore, the overlapped DEGs were identified with 242 genes regulated in homo-direction but 25 regulated in the opposite treated with GL-V9 or DZNeP, these genes mainly influenced DNA replication, chromatin structures, and DNA damage response (Fig2.G). GL-V9 and/or DZNeP down-regulated the EZH2 expression, induced the decrease of p-AKT and c-Myc, and the increase of p53 in U937 cells (Fig. 2H). These data indicate that GL-V9+DZNeP may exert the anti-leukemia effect by inducing DNA damage via targeting EZH2/ PI3K/AKT signaling and the p53-c-Myc axis in the cells. EZH2 inhibition modifies the chromatin structure and decondensed the H3K27me3-marked chromatin, making AML cells more accessible to the nuclear-attacked agent GL-V9. The mechanism model is depicted in Fig. 2I. Conclusions GL-V9 is an effective novel nature compound against AML and exhibited strong synergistic effects with the epigenomic drug EZH2 inhibitor DZNeP potentially by inducing DNA damage-mediated mitotic catastrophe through targeting EZH2/ PI3K/AKT signaling and p53-cMyc axis. Our results provide pre-clinical evidence for the new combination as a promising clinical option for AML patients.

HDAC Inhibitor Synergizes with GL-V9, a Derivative of Wogonin, to Suppress Acute Myeloid Leukemia By Downregulating ESPL1 and PLK4

Background Developing more effective non-chemotherapy options is emerging needed for acute myeloid leukemia (AML). GL-V9, a newly synthetic flavonoid derivative, exhibits anticancer activities with low toxicity as its nature features, however, the anti-leukemia effect and molecular mechanism against AML remain elusive. HDACs inhibitors are promising effective therapies for cancers. Chidamide (CS055/HBI-8000) is a benzamide histone deacetylase (HDAC) inhibitor that induces growth inhibition, cell cycle arrest, and apoptosis in MDS and AML. Here, we sought to determine the potential synergistic anti-leukemia effect of Chidamide combined with GL-V9 in AML. Methods Cell proliferation assays were measured by Cell Counting Kit-8(CCK-8) in AML cells; CalcuSyn was used for synergy analysis. Cell cycle and apoptosis were measured by flow cytometry analysis. Transcriptome was analyzed by RNA-seq in U937 cells treated with 10μM Chidamide and in MV4-11 treated with 4μM GL-V9. qPCR was utilized for gene expression; R2 genomics analysis and visualization application were used for comparison of the expression difference and the Kaplan-Meier overall survival analysis was conducted by the Gene Expression Profiling Interactive Analysis (GEPIA) platform. Results GL-V9 had a dose-dependent effect on cell proliferation arrest in U937 and MV4-11 cells. Chidamide significantly sensitized this effect of GL-V9 versus single-drug controls, and CalcuSyn analysis showed the synergistic effect of the combination (Fig.1A). The combination also significantly increased the % of apoptotic cells versus single-drug controls (p<0.0001) (Fig1.B). Chidamide induced G0/G1-phase arrest and GL-V9 induced G2/M arrest, whereas the combination significantly decreased the % of S-phase cells (Fig.1C). These data indicate that Chidamide+GL-V9 combination results in the synergistic effect on cell growth inhibition, apoptosis and cell cycle arrest in AML. Next, the drug-induced change of the global transcriptome was analyzed. The significantly different expression genes (DEGs) were identified upon GL-V9 treatment and Chidamide treatment versus vehicle control. 1663 DEGs are identified upon GL-V9 treatment and 3756 DEGs upon Chidamide, in which 1405 were intersected regulated (1231 genes changed in the same direction but 174 changed in the opposite (Fig.2AB). The overlapped DEGs are mainly enriched in cell cycle regulation, DNA repair, chromosome segregation, spindle organization, DNA damage, etc. (Fig2.C). ESPL1 and PLK4 are at the top of the overlapped down-regulated DEGs; and qPCR results confirmed their mRNA levels are significantly downregulated by GL-V9+Chidamide, GL-V9, and Chidamide versus the vehicle control (p<0.0001) (Fig. 2D). ESPL1 encoded protein, Separase is an enzyme resolving sister chromatid cohesion, and plays a pivotal role in cell division and oncogenesis. PLK4 (polo-like kinase 4) is a key regulator of centrosome duplication and the substrate of histone acetyltransferases, and PLK4 overexpression leads to centrosome amplification in human cancer and contributes to multipolar spindle assembly. Our results not only indicated that the combination exerts its anti-tumor effect through down-regulation of ESPL1 and PLK4 expression but also reveal their oncogenic roles in AML. Indeed, the mRNA levels of ESPL1 and PLK4 are significantly high expressed in AML patients versus normal BM controls, and ESPL1 high expression is correlated with poor prognosis (Log-rank p=0.0039) (Fig2.E). In addition, our data showed that the expression of the anti-apoptosis genes BCL2 and BCL2L1 are significantly decreased, and the early apoptosis indicators, Caspase-3 and Casepase-9 increased by the combination versus the single-drug controls in U937 cells (Fig2.F). The proposed mechanism model is summarized in Fig. 2G. Conclusion Our data indicate that HDAC inhibitor Chidamide significantly synergizes GL-V9-induced cell growth inhibition, apoptosis, and cell cycle arrest in AML, and the underlying mechanism by suppressing the expression of ESPL1 and PLK4, the key regulators of cell division and proliferation. Our results also provide a potential chemotherapy-free option for AML patients.

Azacitidine Combined with Novel Flavonoid Derivative GL-V9 Demonstrated Synergistic Anti-Leukemia Effect in Acute Myeloid Leukemia By Targeting DDIT4/mTOR Signaling

Background Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy characterized by the clonal expansion of malignant progenitor cells and impaired cell differentiation. GL-V9, a nature compound derived from wogonin, has shown superior anti-tumor potential by inhibiting cancer cell growth. Azacitidine (AZA), a DNA hypomethylation agent, has demonstrated therapeutic efficacy against AML. In this study, we investigated the anti-leukemia effect and potential mechanism of AZA combined with GL-V9 in AML cells, aiming to provide evidence for future clinical treatment. Methods We employed Cell Counting Kit-8 (CCK-8) to assess cell viability, Annexin-V/PI staining followed by flow cytometry analysis to measure apoptosis. CalcuSyn analysis was used to evaluate the synergistic effect. RNA-seq was performed in U937 cells and differentially expressed genes (DEGs) were identified and subjected to KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis. RT-qPCR and Western Blot were used to examine gene expression. Results Our results demonstrated significant cell proliferation arrest in U937 and MV4-11 cells treated with the combination of AZA and GL-V9, compared to the single drug ( Fig. 1A&B). CalcuSyn analysis showed a strong synergistic effect for the combination ( Fig. 1A&B). Similar results were also found in primary AML cells derived from 2 AML patients [patient 1 exhibited t(6;11) (q27;q23) chromosomal translocation, while Patient 2 presented with secondary AML, transformed from CMML (Chronic Myelomonocytic Leukemia) and featured ASXL1 and SRSF2 mutations] ( Fig. 1C&D). Moreover, AZA plus GL-V9 induced a substantial increase in cell apoptosis in U937 and MV4-11 cells compared to the single drug ( Fig. 1E&F). Consistently, the AZA+GL-V9 combination led to a notable increase in the protein level of Bax, BAD, BIM, and a decrease in BCL2 ( Fig. 1G). These data indicated the combination of AZA with GL-V9 has synergistic anti-leukemia effects in AML. To understand the underlying mechanisms of this synergy, we performed RNA-seq analysis in U937 cells, identifying 1385 and 586 DEGs (|log 2FC|≥2.0, P<0.05) upon AZA or GL-V9 treatment, respectively ( Fig. 2A). The mTOR signaling pathway exhibits prominent enrichment in the KEGG analysis of the overlapping DEGs between AZA and GL-V9 ( Fig. 2B). DDIT4, a negative regulator of mTOR emerged as one of the top DEGs in response to both AZA and GL-V9 treatment. Importantly, the AZA+GL-V9 treatment exhibited a higher expression level of DDIT4 compared to either drug alone and suppressed the phosphorylation of mTOR ( Fig. 2C). Additionally, the DDIT4 expression level was significantly decreased in AML patients, which derived from a public database (TCGA-AML, GSE13159)] ( Fig. 2D) and Zhongda Hospital (Nanjing, China) compared to the healthy controls ( Fig. 2E). To be noticed, high DDIT4 expression was associated with extended overall survival (P=0.021) ( Fig. 2F) and relapse-free survival (P=0.015) ( Fig. 2G), indicating DDIT4 may act as a tumor suppressor in AML. These findings suggested that the combination may exert the anti-leukemia effect by targeting the DDIT4/mTOR signaling pathway, as summarized in Fig. 2H. Conclusions Our study provides novel evidence of the synergistic effect on cell growth arrest and apoptosis treated with a new nature compound derived from wogonin combined with AZA in AML. Furthermore, we identified the mechanism underlying the synergy through targeting of DDIT4/mTOR signaling. These results offer preliminary support for the potential application of this combination therapy in treating AML patients.

Chalcones: The flavonoid derivatives synthesis, characterization, their antioxidant and in vitro/in vivo antidiabetic potentials

Chalcones (designated JA1, JA2 and JA3) were prepared from aromatic aldehyde and acetophenone which were then characterized using various spectroscopic techniques. The antioxidant potential of synthesized compounds was evaluated against DPPH free radical whereas the antidiabetic potential was determined against alpha glucosidase. Further the antidiabetic potential of the synthesized compounds was evaluated in rat model which were given orally experimental animals in doses 10 and 20 mg/kg body weight. The blood biochemical parameters like total cholesterol, triglycerides, alanine phosphatase, serum glutamic pyruvic transaminase, serum glutamic oxaloacetic transaminase, serum creatinine, HDL, and LDL levels were determined using commercially available kits. The antioxidant potential was found high for JA3 followed by JA2 with IC50 value of 64.02 ± 1.47 μg/ml whereas against alpha glucosidase again the same compound with IC50 of 63.04 μg/ml exhibited highest inhibitory potential. The blood glucose level was brought to almost normal level (126.88 and 119.13 mg/dl at 10 and 20 mg/kg body weight) in diabetic rats (induced by STZ) by compound JA3 at the tested doses in comparison to acarbose at day 28th. The blood biochemical parameters were normalized in diabetic rats by compound JA3 compared with diabetic control group. Based on the results JA3 should be considered as effective antioxidant and antidiabetic drug candidate.

A comparative study of Ghanaian propolis extracts: Chemometric analysis of the chromatographic profile, antioxidant, and hypoglycemic potential and identification of active constituents

Diabetes is a disease characterized by high post-prandial glucose levels, which lead to other complications such as peripheral end organ damage. The use of enzyme inhibitors in the management of Type-2 diabetes ensure the control of blood glucose levels via the control of carbohydrate metabolism. The use of standard agents such as acarbose is associated with unwanted side effects hence the need to investigate other sources of antihyperglycemic agents. Propolis, a natural substance from bees, possesses diverse biological activities including antioxidant, antimicrobial and antidiabetic properties. However, the phytochemical content of propolis and its extracts may vary depending on the geographical area, the solvent of extraction and type of bees. This study represents the first attempt to compare different extracts of propolis from the same source in sub-Saharan Africa. In this study, the effect of solvent and source of Ghanaian propolis on parameters such as the total phenolic and flavonoid contents, chromatographic profile, antioxidant and α-amylase inhibitory effects were investigated with the aim of identifying and characterizing the most promising extract, which could be of direct or indirect benefit in the management of Type-2 diabetes.Combinations of water, ethanol-water and ethanol extracts were prepared from propolis from three regions. Phytochemical screening was performed on the extracts after which the Folin Ciocalteu method and aluminum chloride colorimetric assay were used to estimate the total phenolic and flavonoid contents respectively. Antioxidant potential of extracts was estimated using DPPH and phosphomolybdenum assays. In-vitro α-amylase inhibition assay was used to investigate hypoglycemic effect of the extracts. Statistical tools such as ANOVA, principal component analysis, hierarchical cluster analysis employed to determine sources of variations within the data obtained, to classify the extracts based on activity and to predict the most effective extract. This extract was then subjected to UHPLC-Q-TOF MS/MS and GC–MS techniques to characterize the constituents.Chemometric analysis of the data obtained showed that the variations in the data could be explained by both propolis source and extraction solvent. Though ethanol extracts generally contained more constituents, the more notable activities were in the ethanol-water extracts. The ethanol-water extract of Bono East propolis (EWBE) was the most potent DPPH radical scavenger (IC50 of 149.37 ± 2.90 µg/mL as compared to 116.60 ± 0.93 µg/mL GAE standard). It was also one of the three extracts which were more potent than acarbose (369.89 µg/mL) in the α-amylase inhibition assay. The predominant constituents from the LC-MS dereplication of EWBE were caffeic acid and flavonoid derivatives whilst 5,5-dimethyl-1-oxa-5 silacyclononanone-9 was the most significant active constituent identified through the GC–MS analysis. The identified constituents are known to have strong antioxidant and antidiabetic properties.The effects of source and solvent of extraction on the biological and physicochemical properties of propolis in Ghana have been quantified using statistical tools. The combined biological effects of propolis suggest a possible role in their usage in the management of type-2-diabetes and its related complications. Ethanol-water extracts were the most promising with EWBE showing the strongest antihyperglycemic activity. Such extracts represent leads towards further research into toxicity and formulation in order to develop safe and useful products for the management of type-2 diabetes.

Corylus avellana "Nocciola Piemonte": metabolomics focused on polar lipids and phenolic compounds in fresh and roasted hazelnuts.

The common hazel plant (Corylus avellana L., Betulaceae) is one of the most popular tree nuts widespread in Europe and Asia. In Italy, there are different cultivars among which the cultivar affording the valuable hazelnut "Tonda Gentile Trilobata," also known as "Tonda Gentile delle Langhe," covered by the Protected Geographical Indication (PGI) label "Nocciola Piemonte" (NP), known for its sweetness, cooked-bread aroma, and the low intensity of the burnt aroma. In order to obtain a detailed and in-depth characterization of the polar fraction of fresh (NPF) and roasted (NPR) kernels of NP the analysis of the n-butanol extracts by liquid chromatography coupled to electrospray ionization and high-resolution mass spectrometry (LC-ESI/HRMS) was carried out. Moreover, to evaluate the quantitative distribution of the most representative polar lipids in NPF and NPR, the analysis by liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) was performed. To unambiguously identify the phenolic compounds highlighted by the LC-ESI/HRMS profiles, they were isolated from the n-butanol extract and characterized by Nuclear Magnetic Resonance (NMR) experiments. Finally, the ability of the isolated compounds to exert radical scavenging activity and to inhibit the lipid peroxidation induced by H2O2 or H2O2/Fe2+ was tested by Trolox Equivalent Antioxidant Capacity (TEAC) and thiobarbituric acid reactive substances (TBARS) assays, respectively. The LC-ESI/HRMS allowed to ascertain the presence of phenolic compounds and multiple classes of polar lipids including phospholipids, glycolipids, sphingolipids, and oxylipins. The quantitative analysis highlighted in NPR fraction a lipid content three times higher than in NPF, evidencing lyso-phospholipids and phospholipids as the most represented lipid classes in both NPF and NPR, together accounting for 94 and 97% of the considered lipids, respectively. Furthermore, phytochemical analysis permitted to identify flavonoid and diarylheptanoid derivatives. In particular, quercetin 3-O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranoside and myricetin-3-O-α-L-rhamnopyranoside showed the highest antioxidant activity, exhibiting TEAC values similar to that of quercetin, used as reference compound (2.00 ± 0.03 and 2.06 ± 0.03 mM vs 2.03 ± 0.03 mM, respectively). Moreover, most of the tested compounds were found to reduce lipid peroxidation induced by H2O2 and H2O2/Fe2+ more than curcumin used as positive control, with myricetin-3-O-α-L-rhamnopyranoside determining 44.4 % and 34.1 % inhibition percentage, respectively.

Investigation of the Potential Targets behind the Promising and Highly Selective Antileishmanial Action of Synthetic Flavonoid Derivatives.

Leishmaniases are among the neglected tropical diseases that still cause devastating health, social, and economic consequences to more than 350 million people worldwide. Despite efforts to combat these vector-borne diseases, their incidence does not decrease. Meanwhile, current antileishmanial drugs are old and highly toxic, and safer presentations are unaffordable to the most severely affected human populations. In a previous study by our research group, we synthesized 17 flavonoid derivatives that demonstrated impressive inhibition capacity against rCPB2.8, rCPB3, and rH84Y. These cysteine proteases are highly expressed in the amastigote stage, the target form of the parasite. However, although these compounds have been already described in the literature, until now, the amastigote effect of any of these molecules has not been proven. In this work, we aimed to deeply analyze the antileishmanial action of this set of synthetic flavonoid derivatives by correlating their ability to inhibit cysteine proteases with the action against the parasite. Among all the synthesized flavonoid derivatives, 11 of them showed high activity against amastigotes of Leishmania amazonensis, also providing safety to mammalian host cells. Furthermore, the high production of nitric oxide by infected cells treated with the most active cysteine protease B (CPB) inhibitors confirms a potential immunomodulatory response of macrophages. Besides, considering flavonoids as multitarget drugs, we also investigated other potential antileishmanial mechanisms. The most active compounds were selected to investigate another potential biological pathway behind their antileishmanial action using flow cytometry analysis. The results confirmed an oxidative stress after 48 h of treatment. These data represent an important step toward the validation of CPB as an antileishmanial target, as well as aiding in new drug discovery studies based on this protease.

Development and In silico ADMET Analysis of Novel Flavonoids Derivatives as Potent, Non-Competitive and Selective PTP1B Inhibitors

Diabetes mellitus is a serious disease that threatens human health. The most prevalent type of diabetes mellitus is type 2 (T2DM) which is characterized by the lack of insulin secretion and resistance to insulin in target tissues. Protein Tyrosine Phosphatase 1B (PTP1B) plays an important role in the dephosphorylation of phospho-tyrosine residues from the insulin receptor and its substrate. Studies have shown that overexpression of PTP1B protein and its increased activation have been associated with insulin resistance and thus it is a promising therapeutic target for type 2 diabetes. The discovery of selective and effective inhibitors on the active target site present a great challenge due to the site charge and the high degree of conserved active site. Therefore, the identified allosteric site of enzyme PTP1B was chosen to design and evaluate ligands based on effectiveness and selectivity, then filter the compounds based on their ADMET properties in silico to identify the potential inhibitors of the PTP1B enzyme. Among the designed molecules, 14 compounds were obtained with better affinity and selectivity for PTP1B. Some of these compounds showed acceptable pharmacokinetic properties of ADMET and were expected to be non-mutagenic. Thus, they can be considered as promising PTP1B inhibitors.

Antiviral activity of Taurisolo® during bovine alphaherpesvirus 1 infection

Bovine alphaherpesvirus 1 (BoAHV-1), the pathogen causing Infectious Bovine Rhinotracheitis (IBR) and predisposing to polymicrobial infections in cattle, provokes farm economic losses and trading restrictions in the world. However, nontoxic antiviral agents for BoAHV-1 infection are still unavailable, but plant extracts, such as flavonoid derivatives possess activity against BoAHV-1. Taurisolo®, a nutraceutical produced by Aglianico grape pomace, has recently shown promising antiviral activity. Herein, the potential activity of Taurisolo® during BoAHV-1 infection in Madin Darby bovine kidney (MDBK) cells was tested. Taurisolo® enhanced cell viability and reduced morphological death signs in BoAHV-1-infected cells. Moreover, Taurisolo® influenced the expression of bICP0, the key regulatory protein of BoAHV-1, and it strongly diminished virus yield. These effects were associated with an up-regulation of aryl hydrocarbon receptor (AhR), a transcription factor involved in microbial metabolism and immune response.In conclusion, our findings indicate that Taurisolo® may represent a potential antiviral agent against BoAHV-1 infection. Noteworthy, AhR could be involved in the observed effects and become a new target in antiviral therapy.

Comparison of the contents of total polyphenol, total flavonoid, and flavonoid derivatives in unfermented and fermented barley sprouts

Comparison of the contents of total polyphenol, total flavonoid, and flavonoid derivatives in unfermented and fermented barley sprouts

Discovery of novel flavonoid-based CDK9 degraders for prostate cancer treatment via a PROTAC strategy

CDK9 plays a vital role in regulating RNA transcription and significantly impacts the expression of short-lived proteins such as Mcl-1 and c-Myc. Thus, targeting CDK9 holds great promise for the development of antitumor drugs. Natural flavonoid derivatives have recently gained considerable attention in the field of antitumor drug research due to their broad bioactivity and low toxicity. In this study, the PROTAC strategy was used to perform structural modifications of the flavonoid derivative LWT-111 to design a series of flavonoid-based CDK9 degraders. Notably, compound CP-07 emerged as a potent CDK9 degrader, effectively suppressing the proliferation and colony formation of 22RV1 cells by downregulating Mcl-1 and c-Myc. Moreover, CP-07 exhibited significant tumor growth inhibition with a TGI of 75.1% when administered at a dose of 20 mg/kg in the 22RV1 xenograft tumor model. These findings demonstrated the potential of CP-07 as a powerful flavonoid-based CDK9 degrader for prostate cancer therapy.

Chemical characterization, antioxidant and antidiabetic activities of a novel polyherbal formulation comprising of Hordeum vulgare, Elettaria cardamomum and Cicer arietinum extracts

Diabetes mellitus (DM) is the most prevalent endocrine disorder. Numerous individual herbs possess anti-diabetic activity. The seeds of Hordeum vulgare, Elettaria cardamomum and Cicer arietinum are traditionally used to manage DM. The ambition of this work was to formulate the poly-herbal granules (PHGs) comprising of these three functional foods and evaluate their in-vitro antioxidant and antidiabetic potential. The dried seed extracts of Hordeum vulgare, Elettaria cardamomum and Cicer arietinum were used in a ratio of 2.5:1:1 to formulate PHGs by wet granulation method. The ratio of extracts was selected on the basis of traditional phytotherapies popularly used by local Hakeems of Pakistan to achieve glycemic control in diabetic patients resistant to traditional allopathic regime of medicine. The flow properties of developed PHGs were evaluated. The UV–Visible spectroscopic, Fourier Transform Infrared (FTIR) and HPLC-DAD of all seed extracts and PHGs were performed. The in-vitro antioxidant DPPH, FRAP, total antioxidant capacity (TAC) and Nitric Oxide (NO) scavenging assays were carried out on PHGs. The in-vitro antidiabetic activity of PHGs was investigated by alpha-amylase and alpha-glucosidase enzyme inhibition activity. The developed PHGs exhibited excellent flow properties. The UV–Vis spectra of all seed extracts and PHGs demonstrated peak at 278 nm showing the presence of flavonoids and phenols. The FTIR spectra confirmed the existence of flavonoids, and phenols along with amines in seed extracts as well as PHGs. The HPLC-DAD test revealed the existence of gallic acid, ascorbic acid, Quercetin-3-(caffeoyldiglucoside)-7-glucoside, Rosmarinic acid, delphinidin-3,5-diglucosides, Kaempferol-3-feruloylsophoroside-7-glucoside and Phloroglucinol in PHGs. The PHGs exhibited IC50 of 51.23, 58.57, 55.41 and 53.13 μg/mL in DPPH assay, FRAP assay, TAC, Nitric oxide scavenging assays respectively. The PHGs also demonstrated IC50 of 49.97 and 36.16 μg/mL in alpha-amylase and in alpha-glucosidase inhibition assays respectively in dose dependent manner. The developed PHGs exhibited an excellent flow property. These exhibit significant in-vitro antioxidant and antidiabetic profile by virtue of flavonoid and phenolic acid derivatives.

Metabolomics targets tissue-specific responses in alleviating the negative effects of salinity in tef (Eragrostis tef) during germination

Main conclusionSalinity induced metabolite responses resulted in differential accumulation of flavonoids and antioxidant metabolites in shoots and roots suggesting improved antioxidant capacity in providing salt-adaptive phenotype of tef seedling.Tef [(Eragrostis tef) (Zucc.) Trotter] is an important ‘cash crop’ of Ethiopia grown mainly for human food, and development of elite tef cultivars with better performance is vital to Ethiopian farmers and breeders. Soil salinity is one of the key constraints that affects tef yield in the Ethiopian lowlands and Rift valley where cultivation of tef is limited. Being a minor crop, the responses of tef towards salinity is unknown. Salinity involves physiological and metabolite reprogramming that can have major impact on germination and seedling establishment. Here we evaluate the in vitro effect of NaCl on tef germination and associate this with metabolomic approaches to suggest salt tolerance mechanisms. In this study, 19 tef varieties were screened for NaCl tolerance and were investigated using untargeted metabolomics. Screened tef varieties showed differential germination rates with NaCl treatment varying from < 20 to 100%. Viable seedlings exposed to NaCl exhibited purple-red pigment accumulation in the roots except for Beten and Tullu nasy varieties. Metabolite comparisons between shoots and roots showed significant differences and, in particular, roots of salt tolerant tef varieties accumulated flavonoid derivatives as well as sugars and cell wall associated metabolites. These metabolic changes were correlated with patterns of antioxidant capacities and total flavonoid content in shoots and roots and suggested a mitigating response by tef to salinity. Our study highlights the role of flavonoid accumulation following salt stress on tef seedlings and further these findings could be used as targets for selective tef breeding.

Selective extraction of plant bioactive compounds with deep eutectic solvents: Iris sibirica L. as example.

Deep eutectic solvents (DESs) are promising extractants with tuneable properties. However, there is a lack of reports about the influence of the nature of the original DES on obtaining the metabolomic profile of a plant. The aim of this study is to investigate the possibility of obtaining Iris sibirica L. chromatographical profiles with DESs based on various hydrogen bond donors and acceptors as extraction solvents. DESs were prepared by mixing choline chloride or tetrabutylammonium bromide with various hydrogen bond donors and investigated for the extraction of bioactive substances from biotechnological raw materials of I. sibirica L. The obtained extracts were analysed by HPLC with diode array detector (DAD) and Q-MS. Chromatographic profiles for I. sibirica L. extracts by eight choline chloride DESs and six tetrabutylammonium DESs have been obtained. It has been found that selective recovery of bioactive substances can be achieved by varying the composition of DESs. Eleven phenolic compounds were identified in I. sibirica L. using HPLC-MS. Phase separation was observed with acetonitrile for four DESs. New flavonoid derivatives have been found in DES extracts compared with methanol extracts. The results showed the possibility of DES usage for extraction without water addition. Selectivity of DESs varies depending on the chemical composition of hydrogen bond donors and acceptors. Choline chloride is a more suitable hydrogen bond acceptor for the flavonoid extraction. Choline chloride-lactic acid (1:1) DES has demonstrated a metabolic profile that was the closest to the methanol one and enhanced the extraction up to 2.6-fold.

A New Flavonoid Derivative and Inhibitory Effects on Xanthine Oxidase and α-glucosidase from Glinus oppositifolius

Abstract: In previous studies on bioactivities, some extracts from Glinus oppositifolius possessed antimicrobial, antifungal, antiplasmodial, anti-inflammatory, anti-diarrhoeic, antihyperlipidemic, and hepatoprotective. However, information on the xanthine oxidase inhibitors’ properties of G. oppositifolius is still limited. For the purpose of discovering new leads with potential α-glucosidase inhibition, the less explored plant G. oppositifolius has been investigated. A new apigenin flavone glucoside, named apigenin-5-O-β-D-glucopyranosyl-8-C-β-Dglucopyranoside (7), together with seven known compounds (spergulacin (1), glinoside C (2), spergulacin A (3), spergulin B (4), spergulin A (5), vitexin (6), vicenin 2 (8)) were identified from Glinus oppositifolius (L.) Aug. DC. aerial parts. The identification of their structures involved a comprehensive analysis utilizing extensive 1D and 2D NMR techniques, mass spectrometry, and in comparison with those from references. Compound 7 (IC50 =257.90 ± 1.00 μM) showed better inhibition of α- glucosidase than acarbose (IC50 = 1021.47 ± 10.79 μM). Compound 8 (IC50 = 56.82 ± 1.95 μM) indicated a good XO inhibitory effect.

LCMS/MS Phytochemical Profiling, Molecular, Pathological, and Immune-Histochemical Studies on the Anticancer Properties of Annona muricata.

Annona muricate is a tropical plant that is well-known for its edible fruit of therapeutic interest. LCMS/MS analyses were applied to identify phytoconstituents of the ethanolic extract of the whole fruits and the aqueous extract of the edible fruit part, in addition to the investigation of their anticancer properties against Ehrlich ascites carcinoma (EAC) in male albino mice. LCMS/MS analyses resulted in the identification of 388 components, representing a wide array of classes of compounds, including acetogenins as the major constituents, alkaloids, flavonoids, and phenolics. Among them, four compounds were tentatively characterized as new compounds (1-4), including an acid derivative, protocatechuic-coumaroyl-quinic acid (1), and three flavonoid derivatives, dihydromyricetin galloyl hexoside (2), apigenin gallate (3), and dihydromyricetin hexouronic acid hexoside (4). Induction with EAC cells resulted in abnormalities in the gene expression of pro-apoptotic genes (Bax and caspase-3) and anti-apoptotic gene (Bcl-2) in the tumor mass. Moreover, microscopic, histopathological, and immune-histochemical examinations of the tumor mass and liver tissues exhibited extensive growth of malignant Ehrlich carcinoma cells and marked hydropic degeneration of hepatocytes and infiltration by tumor cells to liver tissue with marked inflammatory reaction. These abnormalities were markedly ameliorated aftertreatment of EAC mice with A. muricata extracts.