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Euonymus hamiltonianus Wall. is considered a medicinal plant and is used to treat pain, cough, dysuria, and cancer, but a clear phytochemical investigation of its biological activities has yet to be performed. Investigation of chemical constituents of the leaves of Euonymus hamiltonianus Wall. led to the isolation of three new compounds by chromatography techniques, euonymusins A–C (1, 10, and 11), and the acquisition of new spectroscopic data for euonymusin D (2), along with the identification of ten known compounds. The chemical structures of the compounds were established using extensive spectroscopic techniques, including NMR, MS, and hydrolysis, and compared with the published data. These compounds were tested in vitro for their inhibitory effects on beta amyloid production (Aβ42). Compounds 13 and 14 displayed weak inhibition, with IC50 values ranging from 53.15 to 65.43 µM. Moreover, these compounds were also assessed for their inhibitory effects on nitric oxide production. Of these compounds, 3, 4, and 14 displayed inhibitory effects on NO production, with IC50 values ranging from 14.38 to 17.44 µM. Compounds 3, 4, and 14 also suppressed LPS-induced expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein. [ABSTRACT FROM AUTHOR]

Eighteen scalarane sesterterpenoids (1–18), including eight new derivatives (1–8), were isolated from the sponge Hyrtios erectus (family Thorectidae), the extract of which showed cytotoxicity against the HeLa and MCF-7 cell lines. Of the new derivatives, six compounds (1–6) were found to contain a γ-hydroxybutenolide moiety capable of reversible stereoinversion at the hydroxylated carbon center. Under the influence of other adjacent functional groups, each derivative exhibited a different stereochemical behavior, which was fully deduced by ROESY experiments. All the isolated compounds were examined for their cytotoxicity by MTS assay using staurosporine as a positive control (IC50 0.18 and 0.13 μΜ against HeLa and MCF-7 cells, respectively), and they were found to show weak growth inhibitory activities against HeLa and MCF-7 cells, with a minimal IC50 value of 20.0 μΜ. The compounds containing a γ-hydroxybutenolide moiety (1–3, 10, 12) showed cytotoxicity, with IC50 values ranging from 24.3 to 29.9 μΜ, and the most potent derivative was heteronemin (16). Although the cytotoxicities of isolated compounds were insufficient to discuss the structure–activity relationship, this research could contribute to expanding the structural diversity of scalaranes and understanding the stereochemical behavior of γ-hydroxybutenolides. [ABSTRACT FROM AUTHOR]

Five new compounds, 10-oxomornigrol F ( 1 ), (7″ R )-(−)-6-(7″-hydroxy-3″,8″-dimethyl-2″,8″-octadien-1″-yl)apigenin ( 2 ), ramumorin A ( 3 ), ramumorin B ( 4 ), and (4 S ,7 S ,8 R )-trihydroxyoctadeca-5 Z -enoic acid ( 5 ), together with 31 known compounds ( 6–36 ), were isolated from the twigs of Morus alba (Moraceae). The chemical structures of these compounds were established using spectroscopic analyses, 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and Mosher's methods. The anti-inflammatory activities of the compounds were evaluated by investigating their ability to inhibit lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW 264.7 cells. Compounds 1 , 2 , 13 , 17 , 19 , 25 – 28 , and 32 showed inhibitory effects with IC 50 values ranging from 2.2 to 5.3 μg/mL. Compounds 1 , 2 , 17 , 25 , and 32 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression in a concentration-dependent manner. In addition, pretreating the cells with compound 1 , 17 , and 32 significantly suppressed LPS-induced expression of cyclooxygenase-2 (COX-2) protein. [ABSTRACT FROM AUTHOR]

Sponges are prolific sources of various natural products that have provided the chemical scaffolds for new drugs. The sponges of the genus Petrosia inhabit various regions and contain a variety of biologically active natural products such as polyacetylenes, sterols, meroterpenoids, and alkaloids. This review aims to provide a comprehensive summary of the chemical structures and biological activities of Petrosia metabolites covering a period of more than four decades (between 1978 and 2020). It is also described in this review that the major groups of metabolites from members of the genus Petrosia differed with latitude. The polyacetylenes were identified to be the most predominant metabolites in Petrosia sponges in temperate regions, while tropical Petrosia species were sources of a greater variety of metabolites, such as meroterpenoids, sterols, polyacetylenes, and alkaloids. [ABSTRACT FROM AUTHOR]

Three new sesquilignans, zijusesquilignans A-C (1 – 3), together with fifteen known compounds (4 – 18), were isolated from fruits of Ziziphus jujuba var. inermis Rehder (Rhamnaceae). Their chemical structures were established using spectroscopic analyses including 1D- and 2D-NMR, HR-EIMS, and ECD spectra. These compounds were assessed for their inhibitory effects on nitric oxide (NO) production. Of these compounds, 1 – 3 and 17 displayed inhibitory effects on NO production, with IC 50 values ranging from 18.1 to 66.4 μM. Pretreatment with 1 and 17 significantly suppressed LPS-induced expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein in cells. Moreover, compounds 1 – 3 , 7 , 9 , and 17 exhibited cytotoxic activities against three human tumor cell lines, with IC 50 values ranging from 8.4 to 44.9 μM. Unlabelled Image [ABSTRACT FROM AUTHOR]

The flower buds of Cleistocalyx operculatus are used as an important ingredient in herbal tea and herbal products in several tropical countries. However, their protective effects and underlying mechanisms on lipopolysaccharide (LPS)-induced endotoxic shock remain unclear. The aim of this study was to investigate the anti-inflammatory effects of ethanol extract of C. operculatus flower buds (ECO) and its major constituent 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone (DMC) in macrophages and in an experimental LPS-induced sepsis mouse model. ECO inhibited the LPS-induced production and expression of pro-inflammatory mediators in macrophages. In an endotoxic shock mouse model, the oral administration of ECO rescued LPS-induced mortality, and attenuated LPS-induced increases in the serum levels of pro-inflammatory mediators, and damage of the lung and liver tissues. ECO increased the nuclear translocation of the nuclear factor erythroid 2-related factor 2 (Nrf2), as well as the expression of Nrf2 target genes, including heme oxygenase-1 (HO-1), in macrophages. Similar to the effects of ECO, DMC also inhibited the LPS-induced inflammatory response in macrophages and endotoxic shock in mice, and activated the Nrf2/HO-1 pathway. In conclusion, our findings suggested that ECO and its major constituent, DMC, attenuated LPS-induced endotoxic shock by activating the Nrf2/HO-1 pathway. Image 1 • The flower buds of Cleistocalyx operculatus are used as an ingredient in herbal products in several tropical countries. • The anti-inflammatory effects of C. operculatus flower buds (ECO) and its major constituent DMC are demonstrated. • ECO and DMC attenuates lipopolysaccharide-induced inflammatory response in macrophages and endotoxic shock in mice. • The Nrf2/HO-1 pathway is attributable to the anti-inflammatory properties of ECO and DMC in macrophages. • The mechanism explains the anti-inflammatory effects of ECO and DMC. [ABSTRACT FROM AUTHOR]

As part of our continuous program to identify new potential candidates for controlling osteolytic bone diseases from natural products, the alkaloid fraction of barley ( Hordeum vulgare var. hexastichon ) grass (HVA) significantly inhibited RANKL-induced osteoclast formation and protected mice from LPS-induced bone loss. A phytochemical investigation of HVA afforded nine indole alkaloids, including one new compound [hordeumin A ( 1 )] and eight known analogues ( 2 - 9 ). Of them, four ( 1 , 2 , 4 , and 5 ) were anti-osteoclastogenic compounds. Of these four, compound 5 significantly suppressed RANKL-induced osteoclast formation, actin ring formation, and bone resorption in a concentration-dependent manner. It also suppressed the RANKL-induced NF-κB and MAPK signaling pathways and the activation of c-Fos and NFATc1. Compound 5 also reduced the expression levels of osteoclast-specific marker genes, including TRAP, CtsK, DC-STAMP, OSCAR, and MMP9. Our findings suggest that HVA and its alkaloid constituents could be valuable candidates for the prevention and treatment of osteolytic bone diseases.

Insulin resistance causes type 2 diabetes; therefore, increasing insulin sensitivity is a therapeutic approach against type 2 diabetes. Activating AMP-activated protein kinase (AMPK) is an effective approach for treating diabetes, and reduced insulin receptor substrate-1 (IRS-1) protein levels have been suggested as a molecular mechanism causing insulin resistance. Thus, dual targeting of AMPK and IRS-1 might provide an ideal way to treat diabetes. We found that 15,16-dihydrotanshinone I (DHTS), as a C1-Ten protein tyrosine phosphatase inhibitor, increased IRS-1 stability, improved glucose tolerance and reduced muscle atrophy. Identification of DHTS as a C1-Ten inhibitor revealed a new function of C1-Ten in AMPK inhibition, possibly through regulation of IRS-1. These findings suggest that C1-Ten inhibition by DHTS could provide a novel therapeutic strategy for insulin resistance-associated metabolic syndrome through dual targeting of IRS-1 and AMPK.