Effect of pinocembrin isolated from Alpinia zerumbet on osteoblast differentiation

Cytotechnology - Bone mass is regulated by osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Osteoporosis is a bone metabolism disorder in which bone mass decreases due to...     

In silico analyses of major active constituents of fingerroot (Boesenbergia rotunda) unveils inhibitory activities against SARS-CoV-2 main protease enzyme

Boesenbergia rotunda (L.) Mansf., commonly known as fingerroot is a perennial herb in the Zingiberaceae family with anticancer, anti-leptospiral, anti-inflammatory, antioxidant, antiulcer, and anti-herpes viral activities. While the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inhibitory activity of B. rotunda extract has been recently found, the active compounds contributing to this activity are yet unknown. The main protease (M^pro) enzyme is one of the most well established therapeutic targets among coronaviruses which plays a vital role in the maturation and cleavage of polyproteins during viral replication. The current work aims to identify active phytochemical substances from B. rotunda extract that can inhibit the replication of SARS-CoV-2 by using a combined molecular docking and dynamic simulation approaches. The virtual screening experiment revealed that fifteen molecules out of twenty-three major active compounds in the plant extract have acceptable drug-like characteristics. Alpinetin, Pinocembrin, and Pinostrobin have binding energies of ?7.51 kcal/mol, ?7.21 kcal/mol, and ?7.18 kcal/mol, respectively, and can suppress M^pro activity. The stability of the simulated complexes of the lead compounds with the drug-receptor is demonstrated by 100-ns MD simulations. The binding free energies study utilizing molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) and molecular mechanics generalized Born surface area (MM-GBSA) show that the compounds and M^pro enzyme have favourable thermodynamic interactions, which are majorly driven by van der Waals forces. Thus, the selected bioactive phytochemicals from B. rotunda might be used as anti-SARS-CoV-2 candidates that target the M^pro enzyme.     

Flavonoid glycosides from Centaurea pseudoscabiosa subsp. pseudoscabiosa from Turkey

Three flavonoid glycosides were isolated and characterized, together with a further 13 substances belonging to various classes of compounds, in particular two phenolic acids, a coumarin, a sugar and nine flavonoids from the flowered aerial parts of Centaurea pseudoscabiosa subsp. pseudoscabiosa Boiss. et Buhse (Asteraceae). Some considerations about their evolutionary meaning are provided.     

Phytotoxicity of Secondary Metabolites Isolated from Flourensia oolepis S.F.Blake

The aim of this study was to isolate the active principles of Flourensia oolepis S.F.Blake (Asteraceae), which completely inhibited the germination of Raphanus sativus seeds at 10 mg/ml. Flavanone pinocembrin and sesquiterpene ilicol, were isolated by bioassay‐guided fractionation. They were active both against monocot and dicot seeds. Pinocembrin was the most active compound, with an IC₅₀(germination) value of 0.24, 3.40, 3.28, and 3.55 mM against Panicum miliaceum, Avena sativa, Lactuca sativa, and R. sativus, respectively; ilicol, however, exhibited IC₅₀(germination) values of 0.67, 2.73, 5.25, and 9.66 mM for the same species, respectively. Pinocembrin and ilicol inhibited root growth and showed IC₅₀(root growth) values of 0.199, 14.68, 8.05, 7.69 mM , and 1.22, 2.90, 7.35, 8.07 mM , against P. miliaceum, A. sativa, L. sativa, and R. sativus, respectively. Pinocembrin and ilicol reduced Allium cepa cell division without chromosome aberrations.     

Pinocembrin, a major flavonoid in propolis, improves the biological functions of EPCs derived from rat bone marrow through the PI3K-eNOS-NO signaling pathway

The number and quality of endothelial progenitor cells (EPCs) are damaged to varying degrees in patients at risk for developing atherosclerosis. The improvement of the quantity and functions of EPCs can enhance repair of injured endothelial monolayer resulting in inhibiting atherosclerosis. The purpose of this study was to investigate the effect of pinocembrin (PIN), a major flavonoid in propolis on the differentiation and biological functions of EPCs and the potential mechanisms of these effects. Flow cytometry analysis revealed that PIN treatment increased the number of CD34⁺, CD133⁺, FLK-1⁺, CD133⁺/FLK-1⁺ and CD34⁺/FLK-1⁺ mononuclear cells (MNCs) in the peripheral blood of apoE^−/− mice compared to untreated control mice. In vitro PIN treatment significantly increased the number of CD34⁺, CD133⁺, FLK-1⁺ and CD133⁺/FLK-1⁺ MNCs derived from SD bone marrow compared to untreated controls by 42.1, 84.6, 165.9 and 23.1 %, respectively. Additionally, PIN can improve biological functions of EPCs, such as proliferation, migration, adhesion, and in vitro tube formation and NO release. All of these improvements were inhibited by {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002, while L-NAME only inhibited the PIN-induced increase in EPC proliferation and adhesion. We conclude that PIN can both promote the differentiation of EPCs in vitro and ex vivo and improve the biological functions of EPCs. The PI3K-eNOS-NO signaling pathway may be involved in the PIN-induced increase in the proliferation and adhesion of EPCs.     

Antifeedant activity of ethanolic extract from Flourensia oolepis and isolation of pinocembrin as its active principle compound

The ethanolic extract from Flourensia oolepis aerial parts showed strong antifeedant activity against the pest larvae, Epilachna paenulata, with an antifeedant index (AI%) of 99.1% at 100 μg/cm². Based on chromatographic fractionation of the extract, guided by bioassays on E. paenulata, the flavanone pinocembrin (1) was isolated as the most active principle. In a choice assay, compound 1 showed strong antifeedant activity against E. paenulata, Xanthogaleruca luteola and Spodoptera frugiperda with an AI% of 90, 94 and 91% (p < 0.01) respectively, at 50 μg/cm². The dosages necessary for 50% feeding inhibition of the insects (ED₅₀) were 7.98, 6.13 and 8.86 μg/cm², respectively. The feeding inhibitory activity of 1 against E. paenulata was compared with the activity of other structurally related flavonoids like naringenin, which was inactive up to 100 μg/cm², catechin which was nearly 6 times less active than 1, and quercetin which was equally active as 1. The effect of these on the feeding behavior of E. paenulata was also studied.