Paeoniflorin promotes PPARγ expression to suppress HSCs activation by inhibiting EZH2-mediated histone H3K27 trimethylation.

BACKGROUND: The alleviating effect of paeoniflorin (Pae) on liver fibrosis has been established; however, the molecular mechanism and specific target(s) underlying this effect remain elusive. PURPOSE: This study was to investigate the molecular mechanism underlying the regulatory effect of Pae on hepatic stellate cells (HSCs) activation in liver fibrosis, with a specific focus on the role of Pae in modulating histone methylation modifications. METHODS: The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl4)-induced mice and transforming growth factor ß1 (TGF-ß1)-induced LX-2 cells, respectively. Molecular docking, surface plasmon resonance (SPR), chromatin immunoprecipitation-quantitative real time PCR (ChIP-qPCR) and other molecular biological methods were used to clarify the molecular mechanism of Pae regulating HSCs activation. RESULTS: Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl4-induced mice and LX-2 cells. We demonstrated that the inhibitory effect of Pae on the activation of HSCs was dependent on peroxisome proliferator-activated receptor γ (PPARγ) expression and enhancer of zeste homolog 2 (EZH2). Mechanistically, Pae directly binded to EZH2 to effectively suppress its enzymatic activity. This attenuation leaded to the suppression of histone H3K27 trimethylation in the PPARγ promoter region, which induced upregulation of PPARγ expression. CONCLUSION: This investigative not only sheds new light on the precise targets that underlie the remission of hepatic fibrogenesis induced by Pae but also emphasizes the critical significance of EZH2-mediated H3K27 trimethylation in driving the pathogenesis of liver fibrosis.

Si-Ni-San inhibits hepatic Fasn expression and lipid accumulation in MAFLD mice through AMPK/p300/SREBP-1c axis.

BACKGROUND: Soothing the liver and regulating qi is one of the core ideas of traditional Chinese medicine (TCM) in the treatment of fatty liver. Si-Ni-San (SNS) is a well-known herbal formula in TCM for liver soothing and qi regulation in fatty liver treatment. However, its efficacy lacks modern scientific evidence. PURPOSE: This study was aimed to investigate the impact of SNS on metabolic associated fatty liver disease (MAFLD) in mice and explore the underlying molecular mechanisms, particularly its effects on lipid metabolism in hepatocytes. METHODS: The therapeutic effect of SNS was evaluated using in vivo and in vitro models of high-fat/high-cholesterol (HFHC) diet-induced mice and palmitic acid (PA)-induced hepatocytes, respectively. Molecular biological techniques such as RNA-sequencing (RNA-seq), co-immunoprecipitation (co-IP), and western blotting were employed to elucidate the molecular mechanism of SNS in regulating lipid metabolism in hepatocytes. RESULTS: Our findings revealed that SNS effectively reduced lipid accumulation in the livers of HFHC diet-induced mice and PA-induced hepatocytes. RNA-seq analysis demonstrated that SNS significantly down-regulated the expression of fatty acid synthase (Fasn) in the livers of HFHC-fed mice. Mechanistically, SNS inhibited Fasn expression and lipid accumulation by activating adenosine monophosphate (AMP)-activated protein kinase (AMPK). Activation of AMPK suppressed the activity of the transcriptional coactivator p300 and modulated the protein stability of sterol regulatory element-binding protein-1c (SREBP-1c). Importantly, p300 was required for the inhibition of Fasn expression and lipid accumulation by SNS. Furthermore, SNS activated AMPK by decreasing adenosine triphosphate (ATP) production in hepatocytes. CONCLUSION: This study provided novel evidence on the regulatory mechanisms underlying the effects of SNS on Fasn expression. Our findings demonstrate, for the first time, that SNS exerts suppressive effects on Fasn expression through modulation of the AMPK/p300/SREBP-1c axis. Consequently, this regulatory pathway mitigates excessive lipid accumulation and ameliorates MAFLD in mice.

[Research and application of intelligent hyperspectral analysis technology for Chinese materia medica].

With the development of imaging technology and artificial intelligence, hyperspectral imaging technology provides a fast, non-destructive, intelligent, and precise new method for the analysis of Chinese materia medica(CMM). This paper summarized the methods and applications of hyperspectral imaging technology combined with intelligent analysis technology in the field of CMM in recent years, focusing on the acquisition and preprocessing of hyperspectral data, intelligent analysis methods of hyperspectral data, and practical cases of these technologies in the field of CMM. Hyperspectral data of CMM can provide spectral information with nanometer-level resolution and rich spatial texture information simultaneously. This paper summarized the acquisition process, including black-and-white board calibration and region-of-interest extraction, and preprocessing methods including smoothing, differentiation, scale-space, and scattering correction. The feature extraction methods in terms of spectral, spatial, color, and texture were briefly described, and common modeling methods were summarized. Finally, this paper reviewed the research cases of the application of the above methods to the fields of CMM, such as authenticity identification, origin tracing, variety recognition, year identification, sulfur fumigation degree determination, and quantitative measurement.

The antihyperlipidemic equivalent combinatorial components from peel of Citrus reticulata 'Chachi'.

Since the combinatorial components responsible for the antihyperlipidemic activity of Citrus reticulata 'Chachi' (CRC) peels remains unclear, we herein developed a bioactive equivalence oriented feedback screening method to discover the bioactive equivalent combinatorial components (BECCs) from CRC peels. Using palmitic acid (PA)-stimulated hepatocyte model, a combination of 5 polymethoxyflavones (PMFs) including tangeretin, sinensetin, nobiletin, 5,7,8,4'-tetramethoxyflavone and 3,5,6,7,8,3',4'-heptamethoxyflavone was identified to be responsible for the antihyperlipidemic effect of CRC peels. Via evaluation of combination effect by combination index (CI), these 5 PMFs were found to take effect via a synergistic mode. Our data indicated that the antihyperlipidemic mechanism of PMF combination was associated with the inhibition of fatty acid and cholesterol synthesis, and inflammation. Also, the PMF combination exhibited robust antihyperlipidemic effects in HFD-fed rats in vivo. Our study offers evidence-based data to uncover the pharmacological effect of CRC peels.

α-Glucosidase Inhibitory Activities and the Interaction Mechanism of Novel Spiro-Flavoalkaloids from YingDe Green Tea.

Flavoalkaloids are a unique class of compounds in tea, most of which have an N-ethyl-2-pyrrolidinone moiety substituted at the A ring of a catechin skeleton. 1-Ethyl-5-hydroxy-pyrrolidone, a decomposed product of theanine, was supposed to be the key intermediate to form tea flavoalkaloids. However, we have also detected another possible theanine intermediate, 1-ethyl-5-oxopyrrolidine-2-carboxylic acid, and speculated if there are related conjugated catechins. Herein, four novel spiro-flavoalkaloids with a spiro-γ-lactone structural moiety were isolated from Yingde green tea (Camellia sinensis var. assamica) in our continuing exploration of new chemical constituents from tea. The structures of the new compounds, spiro-flavoalkaloids A-D (1-4), were further elucidated by extensive nuclear magnetic resonance (NMR) spectroscopy together with the calculated 13C NMR, IR, UV-vis, high-resolution mass, optical rotation, experimental, and calculated circular dichroism spectra. We also provided an alternative pathway to produce these novel spiro-flavoalkaloids. Additionally, their α-glucosidase inhibitory activities were determined with IC50 values of 3.34 (1), 5.47 (2), 22.50 (3), and 15.38 (4) µM. Docking results revealed that compounds 1 and 2 mainly interacted with residues ASP-215, ARG-442, ASP-352, GLU-411, HIS-280, ARG-315, and ASN-415 of α-glucosidase through hydrogen bonds. The fluorescence intensity of α-glucosidase could be quenched by compounds 1 and 2 in a static style.

Discovery of Camellia sinensis catechins as SARS-CoV-2 3CL protease inhibitors through molecular docking, intra and extra cellular assays.

BACKGROUND AND PURPOSE: Previous studies suggest that major Camellia sinensis (tea) catechins can inhibit 3-chymotrypsin-like cysteine protease (3CLpro), inspiring us to study 3CLpro inhibition of the recently discovered catechins from tea by our group. METHODS: Autodock was used to dock 3CLpro and 16 tea catechins. Further, a 3CLpro activity detection system was used to test their intra and extra cellular 3CLpro inhibitory activity. Surface plasmon resonance (SPR) was used to analyze the dissociation constant (KD) between the catechins and 3CLpro. RESULTS: Docking data suggested that 3CLpro interacted with the selected 16 catechins with low binding energy through the key amino acid residues Thr24, Thr26, Asn142, Gly143, His163, and Gln189. The selected catechins other than zijuanin D (3) and (-)-8-(5''R)-N-ethyl-2-pyrrolidinone-3-O-cinnamoylepicatechin (11) can inhibit 3CLpro intracellularly. The extracellular 3CLpro IC50 values of (-)-epicatechin 3-O-caffeoate (EC-C, 1), zijuanin C (2), etc-pyrrolidinone C and D (6), etc-pyrrolidinone A (9), (+)-gallocatechin gallate (GCG), and (-)-epicatechin gallate (ECG) are 1.58 ± 0.21, 41.2 ± 3.56, 0.90 ± 0.03, 46.71 ± 10.50, 3.38 ± 0.48, and 71.78 ± 8.36 µM, respectively. The KD values of 1, 6, and GCG are 4.29, 3.46, and 3.36 µM, respectively. CONCLUSION: Together, EC-C (1), etc-pyrrolidinone C and D (6), and GCG are strong 3CLpro inhibitors. Our results suggest that structural modification of catechins could be conducted by esterificating the 3-OH as well as changing the configuration of C-3, C-3''' or C-5''' to discover strong SARS-CoV-2 inhibitors.

N-ethyl-2-pyrrolidinone substitution enhances binding affinity between tea flavoalkaloids and human serum albumin: Greatly influenced by esterization.

Formation of catechins-human serum albumin (HSA) complex contributes to stably transporting catechins and regulating their bioavailability. Recently, a new class of catechins namely flavoalkaloids have been reported from tea. The unique structural modification with an N-ethyl-2-pyrrolidinone ring at catechins from these flavoalkaloids has raised our interest in their HSA binding affinity. Thus, we investigated the interaction between HSA and flavoalkaloids by molecular docking, UV-Vis spectroscopy (UV), fluorescence quenching approaches, and surface plasmon resonance (SPR). Thermodynamic parameters suggest that electrostatic forces contribute greatly to the interaction. The binding ability is affected by different ester group (galloyl or cinnamoyl) at 3-OH, N-ethyl-2-pyrrolidinone substituted position (C-6 or C-8), C-2, C-3 and C-5''' configurations, and hydroxyl group numbers at B ring, among which the 3-O-cinnamoyl substitution and 5'''-R configuration present the strongest contributions. UV showed slight changes in the conformation and microenvironment of HSA during the binding process. The quenching and binding constants suggest that the quenching is a static type. The small KD values (1-20 µM) detected by SPR confirmed the strong binding affinities between HSA and flavoalkaloids. Present study will help us to understand the interaction mechanism between flavoalkaloids and HSA, shedding light on structural modification of common catechins to enhance the stability, bioavailability and bioactivities.

Network pharmacology analysis and experimental validation to explore the mechanism of sea buckthorn flavonoids on hyperlipidemia.

ETHNOPHARMACOLOGICAL RELEVANCE: Sea buckthorn is popularly used as a herbal medicine and food additive in the world. Sea buckthorn flavonoids (SF) is reported to have an ameliorative effect on obesity and hyperlipidemia (HLP). AIM: To identify the major bioactive compounds and the lipid-lowering mechanism of SF. METHODS: We used network pharmacology analysis and in vitro experiments to identify the major bioactive compounds and the lipid-lowering mechanism of SF. RESULTS: A total of 12 bioactive compounds, 60 targets related to SF and HLP were identified, and a component-target-disease network was constructed. The KEGG analysis revealed that SF regulated cholesterol metabolism, fat digestion and absorption, and PPAR signaling pathways in HLP. The experimental validation indicated that sea buckthorn flavonoids extract (SFE) and 4 bioactive compounds reduced lipid droplet accumulation, up-regulated the mRNA expression of PPAR-γ, PPAR-α, ABCA1 and CPT1A, etc, down-regulated SREBP-2 and its target gene LDLR, which are closely related to cholesterol conversion into bile acids, de novo synthesis and fatty acids oxidation. The major bioactive flavonoid isorhamnetin (ISOR) also increased the protein expression of PPAR-γ, LXRα and CYP7A1. CONCLUSION: SF might promote cholesterol transformation into bile acids and cholesterol efflux, inhibit cholesterol de novo synthesis and accelerate fatty acids oxidation for ameliorating HLP.

[Effect of compound Longmaining decoction with different combinations on intestinal absorption of puerarin].

To study the effects of compound Longmaining(FFLMN) with different combinations on the intestinal absorption of puerarin. The rat single pass intestinal perfusion model was adopted, and the concentration of puerarin in intestinal samples was determined by HPLC. The effects of different combination groups on the absorption of puerarin in duodenum, jejunum, ileum and colon were investigated. The combined drugs were GG(Puerariae Lobatae Radix), GG-CSL (Puerariae Lobatae Radix compared with Dioscoreae Nipponicae Rhizoma), GG-CX(Puerariae Lobatae Radix compared with Chuanxiong Rhizoma) and FFLMN (compound Longmaining). We found that the absorption rate constant(Ka) and the apparent coefficient(Papp) of puerarin had no significant difference between GG-CSL and FFLMN groups, but significantly higher in GG and GG-CX groups(P<0.05) in the duodenum and ileum. In jejunum and colon, Ka and Papp of puerarin showed significant differences between GG and other groups(P<0.05). At the same time, FFLMN also had significant differences with GG-CSL and GG-CX groups(P<0.05). The results showed that in the whole intestine of rats, FFLMN could significantly promote the absorption of puerarin. In the duodenum and ileum, Dioscoreae Nipponicae Rhizoma played a significant role in promoting absorption of puerarin. In jejunum and colon, Dioscoreae Nipponicae Rhizoma and Chuanxiong Rhizoma have a synergistic effect in promoting absorption of puerarin.

Immunomodulatory Activity of Ganoderma atrum Polysaccharide on Purified T Lymphocytes through Ca2+/CaN and Mitogen-Activated Protein Kinase Pathway Based on RNA Sequencing.

Our previous study has demonstrated that Ganoderma atrum polysaccharide (PSG-1) has immunomodulatory activity on spleen lymphocytes. However, how PSG-1 exerts its effect on purified lymphocytes is still obscure. Thus, this study aimed to investigate the immunomodulatory activity of PSG-1 on purified T lymphocytes and further elucidate the underlying mechanism based on RNA sequencing (RNA-seq). Our results showed that PSG-1 promoted T lymphocytes proliferation and increased the production of IL-2, IFN-γ, and IL-12. Meanwhile, RNA-seq analysis found 394 differentially expressed genes. KEGG pathway analysis identified 20 significant canonical pathways and seven biological functions. Furthermore, PSG-1 elevated intracellular Ca2+ concentration and calcineurin (CaN) activity and raised the p-ERK, p-JNK, and p-p38 expression levels. T lymphocytes proliferation and the production of IL-2, IFN-γ, and IL-12 were decreased by the inhibitors of calcium channel and mitogen-activated protein kinases (MAPKs). These results indicated that PSG-1 possesses immunomodulatory activity on purified T lymphocytes, in which Ca2+/CaN and MAPK pathways play essential roles.

[Effect of puerarin in Longmaining formula on pharmacokinetics-pharmacodynamics correlation in rats with myocardial ischemia].

To study the pharmacokinetics of puerarin in compound Longmaining(FFLMN) in normal rats and myocardial ischemia rats, and investigate its correlation with anti-myocardial ischemia effect of FFLMN. Models of myocardial ischemia rats were produced by subcutaneous injection of isoproterenol(ISO), then FFLMN extract solution was administered by gavage. Orbital sinus blood sampling was collected at different time points after gavage. HPLC-UV method was applied to determine the concentration of puerarin in plasma, and compare the difference in pharmacokinetics between normal rats and model rats after application of same dose of FFLMN. Meanwhile, microplate reader was used to determine IL-6 and SOD activities in plasma of different time points, and draw dose-effect curve. The results indicated that the pharmacokinetics of puerarin conformed to the two-compartment model in both normal group and myocardial ischemia model group. In the comparison of main pharmacokinetic parameters between two groups: AUC0-∞=(11.451±3.228) mg•h•L⁻¹,AUC0-t=(14.047±3.765) mg•h•L⁻¹, Cmax=(5.623±1.40) mg•L⁻¹ in normal group; AUC0-∞=(68.849±50.396 9) mg•h•L⁻¹, AUC0-t= (58.312±45.802) mg•h•L⁻¹,Cmax=(18.456±7.517) mg•L⁻¹ in treatment group. The SOD level was significantly increased and IL-6 concentration was significantly decreased in plasma, indicating that as compared with the normal group, puerarin in FFLMN had a higher plasma concentration, slower elimination rate and higher bioavailability. Therefore, puerarin concentration in plasma has correlation with the anti-myocardial ischemia effect of FFLMN, which could increase SOD level and inhibit the release of IL-6.