Structurally diverse lignans from <i>Solanum lyratum</i>: chemical evidence for their acetylcholinease inhibitory activity

A chemical investigation of Solanum lyratum Thumb. (Solanace) afforded two new lignans (1b and 3) and eleven known lignan analogues (1a, 2a/2b and 4–11). Compounds 1a/1b and 2a/2b were separated as two pairs of enantiomers by chiral high-performance liquid chromatography (HPLC). Their structures were elucidated by detailed spectroscopic and comparative literature data analysis. The absolute configurations of compounds 1a/1b and 2a/2b were determined by comparing the experimental ECD data with the calculated values. All compounds were evaluated for their acetylcholinesterase (AChE) inhibitory activity. Notably, compared to the positive control, compounds 4 and 9 showed obvious AChE inhibition with their IC50 values of 1.30 ± 0.25 and 0.89 ± 0.04 μM, respectively. In addition, the possible interaction between acetylcholinesterase and the active compounds was also investigated by molecular docking.</p

Triterpenes from the fruit of <i>Camptotheca acuminata</i> suppress human hepatocellular carcinoma cell proliferation through apoptosis induction

<p>The fruit of <i>Camptotheca acuminata</i>, a kind of mainly medicinal plant, possesses good antitumor properties. In order to explore the bioactive compounds for the treatment of hepatocellular carcinoma, the study focused on the isolation of cytotoxic compounds from the fruit of <i>Camptotheca acuminata</i>, which led to the discovery of fourteen compounds, including one new triterpene, 3<i>β</i>,20-dihydroxy-30<i>α</i>-methyl,17(29)-<i>β</i>-epoxy-28-norlupane (<b>1</b>), together with thirteen known compounds (<b>2</b>–<b>14</b>). The structures of isolated compounds were demonstrated by spectroscopic methods including 1D and 2D NMR spectroscopy. Moreover, all triterpenes were evaluated for antiproliferative activities against two human hepatocellular carcinoma cell lines, HepG2 and Hep3B. Compound <b>3</b> showed the strongest cytotoxic activity against the HepG2 with IC₅₀ value at 29.6 μM. Further study demonstrated that compound <b>3</b> exhibited cytotoxic activity through the induction of apoptosis.</p

Antioxidant phenolic acids from the leaves of <i>Armeniaca sibirica</i>

<p>Phytochemical investigation of the leaves of <i>Armeniaca sibirica</i> (L.) Lam. led to the isolation of two new phenolic acids (<b>1</b>–<b>2</b>), together with eight known compounds (<b>3</b>–<b>10</b>) from the ethanol extracts of this plant. Structures of these compounds were elucidated through detailed spectroscopic analyses, using 1D-NMR and 2D-NMR in combination with HR-EI-MS techniques. All the compounds were evaluated for their antioxidant capabilities <i>in vitro</i> using 2, 2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), 1, 1′-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assays, and ferric-reducing antioxidant power (FRAP) methods.</p

Expanded Application of Piper nigrum: Guided Isolation of Alkaloids with Inhibitory Activities of AChE/BuChE and Aβ Aggregation

Piper nigrum is a popular crop that can be used as seasoning or as an additive but its active ingredients also have an effect on the nervous system. Nineteen new amide alkaloids (1a/1b, 2–5, 6a/6b, 7, 8a/8b, 9, 10a/10b, 11a–11b, 12–14) were isolated from P. nigrum, guided by inhibitory activity of AChE and LC–MS/MS based on GNPS. The configurations were determined by extensive spectral analysis, Bulkiness rule, and NMR calculations. The inhibitory activities of AChE/BuChE and Aβ aggregation were tested, and the results showed compounds 2, 7, and 12 had significant inhibitory activities. These components were identified in the crude fraction and their relative quantities were tested, which suggested that compound 2 was the index component in the active site from P. nigrum

An Anti-Inflammatory PPAR‑γ Agonist from the Jellyfish-Derived Fungus <i>Penicillium chrysogenum</i> J08NF‑4

An investigation of the jellyfish-derived fungus <i>Penicillium chrysogenum</i> J08NF-4 led to the isolation of two new meroterpene derivatives, chrysogenester (<b>1</b>) and 5-farnesyl-2-methyl-1-<i>O</i>-methylhydroquinone (<b>2</b>), and four known farnesyl meroterpenes. Docking analysis of <b>1</b> showed that it binds to PPAR-γ in the same manner as the natural PPAR-γ agonist amorfrutin B (<b>7</b>). Compound <b>1</b> activated PPAR-γ in murine Ac2F liver cells and increased nuclear PPAR-γ protein levels in murine RAW 264.7 macrophages. Because one of the main biological functions of PPAR-γ agonists is to suppress inflammatory response, an <i>in vitro</i> study was performed to explore the anti-inflammatory potency of <b>1</b> and the mechanism involved. In RAW 264.7 macrophages, <b>1</b> inhibited phosphorylation of the NF-κB p65 subunit and suppressed the expression of the pro-inflammatory mediators iNOS, NO, COX-2, TNF-α, IL-1β, and IL-6. We propose <b>1</b> suppresses inflammatory responses by activating PPAR-γ and subsequently downregulating the NF-κB signaling pathway, thus reducing the expressions of pro-inflammatory mediators

Two new sesquineolignans from the seeds of <i>Crataegus pinnatifida</i> and their <i>β</i>-amyloid aggregation inhibitory activitiy

<p>Two new sesquineolignans, hawthornsesquinins K and L (<b>1</b> and <b>2</b>), were isolated from the seeds of <i>Crataegus pinnatifida</i>. Their structures were determined by spectroscopic analyses, including 1D, 2D NMR and HRESIMS data. All isolated compounds were tested for their <i>β</i>-amyloid aggregation inhibitory activity and neuroprotective effects against H₂O₂-induced damage in SH-SY5Y cells. The results indicated that compound <b>1</b> showed prominent inhibition of A<i>β</i>_1–42 aggregation and significant neuroprotective effect on H₂O₂-induced cellular damage in SH-SY5Y cells.</p

Neuroprotective Effects of 1,2-Diarylpropane Type Phenylpropanoid Enantiomers from Red Raspberry against H₂O₂‑Induced Oxidative Stress in Human Neuroblastoma SH-SY5Y Cells

Red raspberry (<i>Rubus idaeus</i> L.) is an edible fruit-producing species belonging to the Rosaceae family. In our search for the health-promoting constituents from this fruit, four pairs of enantiomeric phenylpropanoids (<b>1a</b>/<b>1b</b>–<b>4a</b>/<b>4b</b>), including three new compounds (<b>1a</b> and <b>2a</b>/<b>2b</b>), were isolated from red raspberry. Their structures were elucidated by a combination of the extensive NMR spectroscopic data analyses, high-resolution electrospray ionization mass spectrometry and comparison between the experimental measurements of electronic circular dichroism (ECD) and calculated ECD spectra by time-dependent density functional theory (TDDFT). In addition, their neuroprotective effects against H₂O₂-induced oxidative stress in human neuroblastoma SH-SY5Y cells were investigated, and the results showed enantioselectivity, in which that <b>3a</b> exhibited noticeable neuroprotective activity, while its enatiomer <b>3b</b> exhibited no obvious protective effect. Further study demonstrated that <b>3a</b> could selectively inhibit the apoptosis induction and reactive oxygen species (ROS) accumulation by enhancing the activity of catalase (CAT) in H₂O₂-treated human neuroblastoma SH-SY5Y cells. These findings shed much light on a better understanding of the neuroprotective effects of these enantiomers and provide new insights into developing better treatment of neurodegenerative diseases in the future

Food Byproducts as a New and Cheap Source of Bioactive Compounds: Lignans with Antioxidant and Anti-inflammatory Properties from Crataegus pinnatifida Seeds

During the process of manufacturing hawthorn (Crataegus pinnatifida) juice and jam, a significant quantity of byproducts (leaves, seeds) is generated. The antioxidant and anti-inflammatory bioassay-guided fractionation of the extract of hawthorn seeds has led to the isolation of eight new lignans, hawthornnins A–H (<b>1</b>–<b>8</b>), and seven known analogues (<b>9</b>–<b>15</b>). Their structures were elucidated by spectroscopic techniques, including 1D and 2D NMR and CD spectra. The radical-scavenging effects of all isolated compounds were investigated. <b>1</b>–<b>6</b> and <b>8</b> showed moderate activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), whereas <b>1</b>–<b>6</b> and <b>14</b> displayed good 2,2′-azinobis­(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radical-scavenging activities that were even more potent than that of trolox. In addition, all isolates were evaluated for their anti-inflammatory activities by detecting the nitric oxide (NO) and tumor necrosis factor α (TNF-α) production by the LPS-induced murine macrophage cell line RAW264.7, and compounds <b>1</b>–<b>7</b>, <b>13</b>, and <b>14</b> exhibited potent inhibition of NO and TNF-α production. The structure–activity relationships of isolated lignans were also examined, and the results obtained show that <i>C. pinnatifida</i> seeds can be regarded as a potential new and cheap source of antioxidants and inflammation inhibitors

<i>ent</i>-Kaurane Diterpenoids with Neuroprotective Properties from Corn Silk (<i>Zea mays</i>)

Thirteen new <i>ent</i>-kaurane diterpenoids, stigmaydenes A–M (<b>1</b>-<b>13</b>), together with two known compounds (<b>14</b>, <b>15</b>), were isolated from the crude extract of corn silk (<i>Zea mays</i>). The structures of the compounds were confirmed by comprehensive spectroscopic analyses. The absolute configuration of compound <b>1</b> was defined by single-crystal X-ray diffraction. The absolute configurations of the compounds were also confirmed by comparison of experimental and calculated specific rotations. The compounds were evaluated for their neuroprotective effects against H₂O₂-induced SH-SY5Y cell injury, and compound <b>8</b> was active at 100 μM, as determined by flow cytometry (annexin V-FITC/PI staining) and Hoechst 33258 staining. The results suggested that compound <b>8</b> could protect neuronal cells from H₂O₂-induced injury by inhibiting apoptosis in SH-SY5Y cells

A new coumarin from <i>Juglans mandshurica</i> Maxim induce apoptosis in hepatocarcinoma cells

<p>In this study, a new coumarin, juglansoside C (<b>1</b>) was isolated from the bark of <i>Juglans mandshurica</i>. Its chemical structure was identified by comprehensive spectroscopic analyses. The <i>in vitro</i> cytotoxicity assay showed that <b>1</b> exhibited moderate cytotoxicity against human hepatocellular carcinoma Hep3B cells with an IC₅₀ value of 70.9 μM. Furthermore, Annexin V-FITC/PI staining assay indicated that <b>1</b> markedly induced apoptosis in Hep3B cells.</p