Loss of protein homeostasis is a hallmark of cellular senescence, and ribosome pausing plays a crucial role in the collapse of proteostasis. However, our understanding of ribosome pausing in senescent cells remains limited. In this study, we utilized ribosome profiling and G-quadruplex RNA immunoprecipitation sequencing techniques to explore the impact of RNA G-quadruplex (rG4) on the translation efficiency in senescent cells. Our results revealed a reduction in the translation efficiency of rG4-rich genes in senescent cells and demonstrated that rG4 structures within coding sequence can impede translation both in vivo and in vitro. Moreover, we observed a significant increase in the abundance of rG4 structures in senescent cells, and the stabilization of the rG4 structures further exacerbated cellular senescence. Mechanistically, the RNA helicase DHX9 functions as a key regulator of rG4 abundance, and its reduced expression in senescent cells contributing to increased ribosome pausing. Additionally, we also observed an increased abundance of rG4, an imbalance in protein homeostasis, and reduced DHX9 expression in aged mice. In summary, our findings reveal a novel biological role for rG4 and DHX9 in the regulation of translation and proteostasis, which may have implications for delaying cellular senescence and the aging process.
G-Quadruplexes ; Cellular Senescence ; Ribosomes/genetics* ; Humans ; Animals ; Mice ; DEAD-box RNA Helicases/genetics* ; Protein Biosynthesis ; RNA/chemistry* ; Neoplasm Proteins

Eight butyl-phthalides, senkyunolide K(1), senkyunolide N(2), butylphthalide(3), senkyunolide I(4), senkyunolide H(5),(Z)-butylidenephthalide(6),(Z)-ligustilide(7), and 3-butylidene-7-hydroxyphthalide(8) were isolated from the aerial part of Ligusticum sinense by column chromatography on silica gel column, ODS, Sephadex LH-20 and semi-preparative HPLC. Their structures were elucidated on the basis of spectroscopic and chemical data, especially NMR and MS. Compound 1 was a new butyl-phthalide and compounds 2-8 were isolated from the aerial part of L. sinense for the first time. Furthermore, the inhibitory activities of compounds 1-8 against the nitric oxide(NO) production induced by lipopolysaccharide(LPS) in mouse RAW264.7 macrophages in vitro were evaluated. The results showed that compounds 1-8 exerted inhibitory activities on NO production with IC_(50) of 19.34-42.16 μmol·L~(-1).
Animals ; Mice ; Nitric Oxide/biosynthesis* ; Ligusticum/chemistry* ; Benzofurans/isolation & purification* ; Drugs, Chinese Herbal/isolation & purification* ; Macrophages/immunology* ; RAW 264.7 Cells ; Molecular Structure

This study investigated the secondary metabolites in the product of rice fermentation with Alternaria alternata and their activity of down-regulating thymosin beta 10(TMSB10) protein expression. The secondary metabolites of A. alternata were separated and purified by various chromatographic separation techniques, including silica gel column chromatography, Sephadex LH-20 column chromatography, and semi-preparative high-performance liquid chromatography. Their structures were identified by spectral techniques such as nuclear magnetic resonance spectroscopy(NMR), infrared spectroscopy(IR), and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS) and comparison with literature data. A total of 10 compounds were isolated and identified, including two new compounds(1S,3S)-2,3-dihydro-3,6-dihydroxy-8-methoxy-1-methylcyclopenta[c][2]benzopyran-5(1H)-one(1), 3,3a, 6-trihydroxy-8-methoxy-1-methyl-2,3,3a, 9b-tetrahydrocyclopenta[c]isochromen-5(1H)-one(2), and the eight known compounds are alternariol 9-methyl ether(3), 1-deoxyrubralactone(4),(3aR)-3,3a-dihydro-1,6-dihydroxy-8-methoxy-3a-methylcyclopenta[c][2]benzopyran-2,5-dione(5), altechromone A(6), alternariol(7), altenuene(8), altenusin(9), and 3'-hydroxyalternariol 5-O-methyl ether(10). The effects of these compounds on TMSB10 expression were tested. Compound 7 showed a significant down-regulation effect on TMSB10 expression with an inhibition rate of 40.5%. The results showed that benzopyrone compounds of A. alternata have the activity of down-regulating the expression of TMSB10 protein, providing theoretical basis and research value for the study of non-small cell lung cancer.
Alternaria/metabolism* ; Down-Regulation/drug effects* ; Humans ; Molecular Structure

The chemical constituents of Commiphora myrrha was investigated by column chromatography on silica gel, ODS, Sephadex LH-20, and semi-preparative HPLC. Their structures were elucidated by comprehensive spectroscopic methods including UV, IR, MS, NMR, as well as ECD calculation. Seven compounds were isolated from the dichloromethane-soluble fraction of C. myrrha and their structures were identified as(1S,2R,4S,5R,8S)-guaiane-2-hydroxy-7(11),10(15)-dien-6-oxo-12,8-olide(1), commipholide E(2), myrrhterpenoid H(3), myrrhterpenoid I(4), myrrhterpenoid E(5), 2α-methoxy-8α-hydroxy-6-oxogermacra-1(10),7(11)-dien-8,12-olide(6), 8,12-epoxy-1α,9α-hydroxy-eudesma-7,11-diene-6-dione(7). Compound 1 was a new compound and named myrrhterpenoid P. Compound 7 was isolated from Commiphora genus for the first time. Compounds 2, 5, and 6 significantly inhibited nitric oxide(NO) production in LPS-stimulated RAW264.7 cells, with IC_(50) values of(49.67±4.16),(40.80±1.27),(47.22±0.87) μmol·L~(-1), respectively [indomethacin as the positive control, with IC_(50) value of(63.92±2.60) μmol·L~(-1)].
Commiphora/chemistry* ; Animals ; Mice ; Resins, Plant/chemistry* ; Sesquiterpenes/isolation & purification* ; Molecular Structure ; Nitric Oxide ; Macrophages/metabolism* ; RAW 264.7 Cells ; Drugs, Chinese Herbal/pharmacology*

Eleven sesquiterpenoids were isolated from the petroleum ether and ethyl acetate extracted fraction of 95% ethanol extract of fresh Centipeda minima by using modern chromatographic separation techniques such as silica gel, MCI, gel, and semi-preparative liquid chromatography. Their structures were identified using spectroscopy and nuclear magnetic resonance(NMR) calculation as minimin A(1), brevilin A(2), minimolide L(3), minimolide A(4), minimolide B(5), arnicolide D(6), microhelenin C(7), 2β-hydroxyl-2,3-dihydrogen-6-O-angeloylplenolin(8), 11α,13-dihydroarnifolin(9),(1S,2R,5R,6S,7S,8S,10R)-6-hydroxy-2-ethoxy-4-oxopseudoguai-11(13)-en-12,8-olide(10), and pulchellin-2-O-isovalerate(11), among which compound 1 was a new compound, and compounds 9-11 were isolated from Centipeda for the first time. The evaluation results of in vitro anti-inflammatory activity showed that compounds 1-11 possessed significant anti-inflammatory activity, with IC_(50) values ranging from(0.13±0.03) to(13.11±0.17) μmol·L~(-1).
Sesquiterpenes/pharmacology* ; Animals ; Asteraceae/chemistry* ; Mice ; Drugs, Chinese Herbal/pharmacology* ; Molecular Structure ; Magnetic Resonance Spectroscopy ; Macrophages/immunology*

Various chromatographic methods were comprehensively applied to study the chemical composition of the ethyl acetate extract from Aucklandiae Radix. The structures of all compounds were identified by analyzing their physicochemical properties and using spectroscopic methods. Two new sesquiterpenoids, named auclappsines A and B(1 and 2) were isolated and identified. Through in vitro high content screening and with the use of a guggulsterone-induced L02 cells, the effects of 1 and 2 on farnesoid X receptor(FXR) protein expression were investigated. The results showed that 1 had a significant FXR activation effect, providing a scientific basis for the development of drugs for the treatment of liver and gallbladder diseases.
Receptors, Cytoplasmic and Nuclear/genetics* ; Humans ; Sesquiterpenes/isolation & purification* ; Drugs, Chinese Herbal/isolation & purification* ; Cell Line ; Molecular Structure

The chemical constituents of the petroleum ether extract derived from the 90% ethanol extract of Elephantopus scaber were investigated. By silica gel column chromatography, C_(18), MCI column chromatography and semi-preparative high performance liquid chromatography, ten compounds were isolated. Their structures were identified as 3β-hydroxy-6β,7β-epoxytaraxeran-14-ene(1), 3β-hydroxyolean-12-en-28-oic acid(2), D-friedoolean-14-ene-3β,7α-diol(3), 3β-hydroxy-11α-methoxyolean-12-ene(4), 3β-hydroxyolean-11,13(18)-diene(5), 11α-hydroxy-β-amyrin(6), betulinic acid(7), 3β-hydroxy-30-norlupan-20-one(8), 6-acetonylchelerythrine(9), and 4',5'-dehydrodiodictyonema A(10) by analysis of the 1D NMR, 2D NMR, MS, and IR spectral data. Among them, compound 1 was a new triterpene and other compounds except compounds 2 and 7 were isolated from this plant for the first time.
Triterpenes/isolation & purification* ; Drugs, Chinese Herbal/isolation & purification* ; Molecular Structure ; Asteraceae/chemistry* ; Chromatography, High Pressure Liquid ; Magnetic Resonance Spectroscopy

The 95% ethanol extract of Stephania hernandifolia was isolated and purified by column chromatography on silica gel and Sephadex LH-20, RP-18 medium-pressure liquid chromatography, and semi-preparative high performance liquid chromatography. The chemical structures of the compounds were identified by NMR and high-resolution mass spectrometry. Four alkaloids were isolated and identified as(-)-8-oxo-2,3,4,10,11-pentamethoxyberberine(1),(-)-8-oxo-11-hydroxy-2,3,4,10-tetramethoxyberberine(2), N-trans-feruloyl tyramine(3), and N-cis-feruloyl tyramine(4). Compounds 1 and 2 were new protoberberine alkaloids, while compounds 3 and 4 were amide alkaloids. All the four compounds were separated from this plant for the first time. The inhibitory activities of compounds 1, 3, and 4 against α-glycosidase were measured by the enzymatic reaction in vitro with 4-nitrophenyl-α-D-glucopyranoside(PNPG) as the substrate. Compounds 3 and 4 showed inhibitory activities against α-glucosidase, with median inhibition concentration(IC_(50)) values of(7.09±0.42) and(31.25±1.14) μmol·L~(-1), respectively.
Berberine Alkaloids/isolation & purification* ; Stephania/chemistry* ; Drugs, Chinese Herbal/isolation & purification* ; Molecular Structure ; alpha-Glucosidases/metabolism* ; Chromatography, High Pressure Liquid ; Alkaloids/isolation & purification*

The seed kernel of Momordica cochinchinensis, i.e., Momordicae Semen, is used for medicinal purposes, but to date, no research has been reported on its chemical constituents. In this study, the chemical constituents of Momordicae Semen were investigated for the first time using silica gel column chromatography, semi-preparative HPLC, HR-MS, and NMR. As a result, eight compounds were isolated and identified as: p-hydroxybenzoic acid-7-O-trehaloside(mubeside A, 1), 2,6-dimethoxyphenol-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside B, 2), 1-O-p-methoxybenzoyl-1,4-benzenediol-4-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside C, 3), 1-O-p-hydroxybenzoyl-1,4-benzenediol-4-O-β-D-apiosyl-(1→2)-β-D-glucoside(mubeside D, 4), gypsogenin-3-O-β-D-galactosyl-(1→2)-β-D-glucuronoside(5), quillaic acid-3-O-β-D-galactosyl-(1→2)-β-D-glucuronoside(6), violanthin(7), and kaempferitrin(8). Compounds 1-4 are new compounds, while compounds 5-8 were isolated from Momordicae Semen for the first time.
Glycosides/isolation & purification* ; Drugs, Chinese Herbal/isolation & purification* ; Molecular Structure ; Magnetic Resonance Spectroscopy ; Chromatography, High Pressure Liquid

The chemical constituents were systematically separated from the roots of Berberis polyantha by various chromatographic methods, including silica gel column chromatography, HP20 column chromatography, polyamide column chromatography, reversed-phase C_(18) column chromatography, and preparative high-performance liquid chromatography. The structures of the compounds were identified by physicochemical properties and spectroscopic techniques(1D NMR, 2D NMR, UV, MS, and CD). Four phenylpropanoids were isolated from the methanol extract of the roots of B. polyantha, and they were identified as(2R)-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone-O-β-D-glucopyranoside(1), methyl 4-hydroxy-3,5-dimethoxybenzoate(2),(+)-syringaresinol(3), and syringaresinol-4-O-β-D-glucopyranoside(4). Compound 1 was a new compound, and other compounds were isolated from this plant for the first time. The anti-inflammatory activity of these compounds was evaluated based on the release of nitric oxide(NO) in the culture of lipopolysaccharide(LPS)-induced RAW264.7 macrophages. At a concentration of 10 μmol·L~(-1), all the four compounds inhibited the LPS-induced release of NO in RAW264.7 cells, demonstrating potential anti-inflammatory properties.
Plant Roots/chemistry* ; Animals ; Mice ; Berberis/chemistry* ; RAW 264.7 Cells ; Macrophages/immunology* ; Drugs, Chinese Herbal/isolation & purification* ; Nitric Oxide/metabolism* ; Molecular Structure ; Anti-Inflammatory Agents/isolation & purification*