Enhancement of Galloylation Efficacy of Stigmasterol and β-Sitosterol Followed by Evaluation of Cholesterol-Reducing Activity

Synthesis of novel nonsteroidal anti-inflammatory galloyl β-sitosterol-loaded lignin-capped Ag-based drug

Biocompatible anti-inflammatory lignin-capped Ag (LCAg) nanoparticles (NPs) were synthesized for the delivery of galloyl β-sitosterol (Galloyl-BS). β-Sitosterol (BS) is effective against inflammatory responses, like cancer-induced inflammations. BS was modified via gallic acid esterification to enhance its anti-inflammatory potential. LCAg NPs were synthesized by a green method and loaded with galloyl-BS. For comparison, pure BS was also loaded onto LCAg NPs in a separate assembly. The antioxidant potential of Galloyl-BS was greater (IC50 177 µM) than pure BS. Materials were characterized by FT-IR, SEM, XRD, and Zeta potential. Using UV-Vis spectroscopy, drug release experiments were performed by varying pH, time, concentration, and temperature. Maximum drug release was observed after 18 h at pH 6 and 40 °C. Galloyl-BS showed improved drug loading efficiency, release %age, and antioxidant activity compared to pure BS when loaded onto LCAg NPs. DLCAg exhibited excellent anti-inflammatory activity in rat models. These findings indicate that galloyl-BS (drug)-loaded LCAg (DLCAg) NPs have the potential as an anti-inflammatory agent without any prior release and scavenging in normal cells.

Advances and Challenges in Plant Sterol Research: Fundamentals, Analysis, Applications and Production

Plant sterols (PS) are cholesterol-like terpenoids widely spread in the kingdom Plantae. Being the target of extensive research for more than a century, PS have topped with evidence of having beneficial effects in healthy subjects and applications in food, cosmetic and pharmaceutical industries. However, many gaps in several fields of PS's research still hinder their widespread practical applications. In fact, many of the mechanisms associated with PS supplementation and their health benefits are still not fully elucidated. Furthermore, compared to cholesterol data, many complex PS chemical structures still need to be fully characterized, especially in oxidized PS. On the other hand, PS molecules have also been the focus of structural modifications for applications in diverse areas, including not only the above-mentioned but also in e.g., drug delivery systems or alternative matrixes for functional foods and fats. All the identified drawbacks are also superimposed by the need of new PS sources and technologies for their isolation and purification, taking into account increased environmental and sustainability concerns. Accordingly, current and future trends in PS research warrant discussion.

Impact of molecular interactions between hydrophilic phytosterol glycosyl derivatives and bile salts on the micellar solubility of cholesterol

Hydrophilic phytosterol glycosyl derivatives are synthetic phytosterol analogues by coupling with the glycosyl moiety to improve the water solubility and bioaccessibility of free phytosterols. The aim of this study is to clarify the molecular interaction of phytosterol glycosyl derivatives with bile salts and the consequent impact on cholesterol solubilization. Sharp nonlinear decrease in the micellar solubility of cholesterol and accompanying changes in particle size, zeta potential and microtopography of mixed micelles were observed when phytosterol glycosyl derivatives were introduced in cholesterol-loaded bile salt micelles. These results suggested that β-sitosterol glycosyl derivatives molecules indeed participated in the formation of mixed micelles. Further, nuclear magnetic resonance showed that the structural change of mixed micelles was caused by the insertion of β-sitosterol glycosyl derivatives via hydrogen bonds with sodium taurocholate, which resulted in the low cholesterol solubilization. Moreover, the hydrogen-bond interactions were apparently influenced by the glycosyl moiety of β-sitosterol glycosyl derivatives. These molecular mechanisms may contribute to the development of cholesterol-absorption inhibitors.

Investigation of the structure of gallate xylose polymers and their antioxidant properties for skin care products

Xylose is the second most abundant monosaccharide in nature, and gallic acid (GA) has properties of antioxidant, anti-inflammatory and anti-bacterial. Hence, the gallate xylose (GX) polymers were synthesized from d-xylose and gallic acid for skin care applications in this paper. Then, the structure, generation mechanisms and the antioxidant activity of the generated polymer were studied. It got the results that: The generated GX polymers have strong antioxidant properties, yielded in 80.1% of GA mass. The DPPH scavenging activity was over 80.0% under the polymer's solution over 0.2 mg/mL. Moreover, the reaction mechanisms of DPPH removal were explained in a new theory based on Mass spectral analysis. Therefore, it demonstrates that the GX polymers of is a potential antioxidant material for skin care products, and it does contribution to the theory of DPPH removal for application in the fields of chemistry, biology and medicine researches.

Development of Galloyl Antioxidant for Dispersed and Bulk Oils through Incorporation of Branched Phytol Chain

In this study, a novel galloyl phytol antioxidant was developed by incorporating the branched phytol chain with gallic acid through mild Steglich esterification. The evaluation of the radical scavenging activity, lipid oxidation in a liposomal model, and glycerol trioleate revealed its superior antioxidant activities in both dispersed and bulk oils. Then, the antioxidant capacity enhancement of galloyl phytol was further explored using thermal gravimetry/differential thermal analysis (TG/DTA), transmission electron microscopy (TEM), and molecular modeling. The EC50 values of GP, GPa, and GE were 0.256, 0.262, and 0.263 mM, respectively, which exhibited comparable DPPH scavenging activities. These investigations unveiled that the branched aliphatic chain enforced the coiled molecular conformation and the unsaturated double bond in the phytol portion further fixed the coiled conformation, which contributed to a diminished aggregation tendency and enhanced antioxidant activities in dispersed and bulk oils. The remarkable antioxidant performance of galloyl phytol suggested intriguing and non-toxic natural antioxidant applications in the food industry, such as effectively inhibiting the oxidation of oil and improvement of the quality and shelf life of the oil, which would contribute to the use of tea resources and extending the tea industry chain.

Synthesis, Physical Properties, and In Vitro-Simulated Gastrointestinal Digestion of Hydrophilic β-Sitosterol Sugar Esters

Hydrophilic β-sitosterol sugar esters were synthesized by a two-step biocatalytic approach using β-sitosterol vinyl adipate as an intermediate. The maximum conversion (above 90%) of β-sitosterol vinyl adipate was achieved using the saccharides glucose, sucrose, and raffinose. The chemical structure of the synthesized esters was confirmed by various techniques. The investigation of physical properties revealed that β-sitosterol sugar esters had enhanced water solubility (3.0-8.0 mM at 35 °C), reduced crystallinity, and high wettability. Their lyotropic liquid crystal properties were observed by polarized light microscopy. Furthermore, β-sitosterol sugar esters could be hydrolyzed into β-sitosterol adipate under simulated intestinal conditions at a low rate (2.83-18.14%). Most β-sitosterol sugar esters probably entered into intestinal bile salt micelles with ester bonds intact and showed up to 10-fold higher in vitro bioaccessibility than free β-sitosterol in non-fat systems. The excellent physical and functional characteristics of β-sitosterol sugar esters suggested their great potential application in the food industry.

The mechanism and active compounds of semen armeniacae amarum treating coronavirus disease 2019 based on network pharmacology and molecular docking

Background

Coronavirus disease 2019 (COVID-19) outbreak is progressing rapidly, and poses significant threats to public health. A number of clinical practice results showed that traditional Chinese medicine (TCM) plays a significant role for COVID-19 treatment.

Objective

To explore the active components and molecular mechanism of semen armeniacae amarum treating COVID-19 by network pharmacology and molecular docking technology.

Methods

The active components and potential targets of semen armeniacae amarum were retrieved from traditional Chinese medicine systems pharmacology (TCMSP) database. Coronavirus disease 2019-associated targets were collected in the GeneCards, TTD, OMIM and PubChem database. Compound target, compound-target pathway and medicine-ingredient-target disease networks were constructed by Cytoscape 3.8.0. Protein-protein interaction (PPI) networks were drawn using the STRING database and Cytoscape 3.8.0 software. David database was used for gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The main active components were verified by AutoDock Vina 1.1.2 software. A lipopolysaccharide (LPS)-induced lung inflammation model in Institute of Cancer Research (ICR) mice was constructed and treated with amygdalin to confirm effects of amygdalin on lung inflammation and its underlying mechanisms by western blot analyses and immunofluorescence.

Results

The network analysis revealed that nine key, active components regulated eight targets (Proto-oncogene tyrosine-protein kinase SRC (SRC), interleukin 6 (IL6), mitogen-activated protein kinase 1 (MAPK1), mitogen-activated protein kinase 3 (MAPK3), vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor (EGFR), HRAS proto-oncogene (HRAS), caspase-3 (CASP3)). Gene ontology and KEGG enrichment analysis suggested that semen armeniacae amarum plays a role in COVID-19 by modulating 94 biological processes, 13 molecular functions, 15 cellular components and 80 potential pathways. Molecular docking indicated that amygdalin had better binding activity to key targets such as IL6, SRC, MAPK3, SARS coronavirus-2 3C-like protease (SARS-CoV-2 3CLpro) and SARS-CoV-2 angiotensin converting enzyme II (ACE2). Experimental validation revealed that the lung pathological injury and inflammatory injury were significantly increased in the model group and were improved in the amygdalin group.

Conclusion

Amygdalin is a candidate compound for COVID-19 treatment by regulating IL6, SRC, MAPK1 EGFR and VEGFA to involve in PI3K-Akt signalling pathway, VEGF signalling pathway and MAPK signalling pathway. Meanwhile, amygdalin has a strong affinity for SARS-CoV-2 3CLpro and SARS-CoV-2 ACE2 and therefore prevents the virus transcription and dissemination.

Exploring the mechanism of Jianpi Qushi Huayu Formula in the treatment of chronic glomerulonephritis based on network pharmacology

This study was to explore the effective components, potential targets, and pathways of Jianpi Qushi Huayu Formula (JQHF) for the treatment of chronic glomerulonephritics (CGN). First, the Chinese Medicine System Pharmacology Database and Analysis Platform (TCMSP), GeneCards, and OMIM databases were used to collect the major active components of JQHF and potential therapeutic targets of CGN. Then, functional enrichment analysis was performed to clarify the mechanisms of the JQHF on CGN. Subsequently, molecular docking was simulated to assess the binding ability of key targets and major active components. Finally, quantitative real-time PCR and western blot were performed for experimental verification of cells in vitro. A total of 55 active ingredients contained and 220 putative identified targets were screened from JQHF, of which 112 overlapped with the targets of CGN and were considered potential therapeutic targets. Then, we found quercetin and kaempferol are two key ingredients of JQHF, which may act on the top 10 screened targets of PPI, affecting CGN through related signal transduction pathways. Subsequently, molecular docking predicted that quercetin and kaempferol bind firm with the top 10 core targets of PPI. Further experiment verified some results and showed that JQHF has protected glomerular mesangial cells from lipopolysaccharide-induced inflammation by inhibiting expressions of IL6, TNF-α, and AKT1, and activating expressions of VEGFA. Based on network pharmacology, we explored the multi-component, multi-target, and multi-pathway characteristics of JQHF in treating CGN, and found that JQHF could act on IL6, TNF-α, VEGFA, and AKT1 to exert the effect of anti-CGN, which provided new ideas and methods for further research on the mechanism of JQHF in treating CGN.

Evidence of TCM Theory in Treating the Same Disease with Different Methods: Treatment of Pneumonia with Ephedra sinica and Scutellariae Radix as an Example

Pneumonia is a serious global health problem and the leading cause of mortality in children. Antibiotics are the main treatment for bacterial pneumonia, but there are serious drug resistance problems. Traditional Chinese medicine (TCM) has been used to treat diseases for thousands of years and has a unique theory. This article takes the treatment of pneumonia with Ephedra sinica as a representative hot medicine and Scutellariae Radix as a representative cold medicine as an example. We explore and explain the theory of treating the same disease with different TCM treatments. Using transcriptomics and network pharmacology methods, GO, KEGG enrichment, and PPI network construction were carried out, demonstrating that Ephedra sinica plays a therapeutic role through the NF-κB and apoptosis signaling pathways targeting PLAU, CD40LG, BLC2L1, CASP7, and CXCL8. The targets of Scutellariae Radix through the IL-17 signaling pathway are MMP9, CXCL8, and MAPK14. Molecular docking technology was also used to verify the results. In short, our results provide evidence for the theory of treating the same disease with different treatments, and we also discuss future directions for traditional Chinese medicine.

Development of a Gemini Interfacial Antioxidant for Oil in Water Emulsion with Gallic Acid and Dodecyl Gemini Chains

In this study, development of the gemini gallate (GG) interfacial antioxidant for oil in water (O/W) emulsion was performed employing Steglich esterification with gallic acid and dodecyl gemini chains through a prepacked column and peristaltic pump-based purification system. The structural identity and purity of the prepared GG and monogallate (MG) were confirmed by NMR, Fourier transform infrared spectroscopy, and high-performance liquid chromatography-mass spectrometry. Further evaluation revealed that the GG possessed excellent radical scavenging activity and superior antioxidant activity in an O/W emulsion relative to the MG, especially under the condition of a reduced amount of the emulsifier. Microscopic investigation by a fluorescent probe and transmission electron microscopy (TEM) unveiled that the extraordinary antioxidant performance in the O/W emulsion was presumably attributed to preferable interfacial location because of the unique gemini molecular architecture. The superior antioxidant activity of the gemini antioxidant holds great promise for antioxidation in O/W emulsions.

Forecasting structure of natural products through color formation process by thin layer chromatography

With booming of computer technology, it is feasible to quantitatively extract valuable information from readily available image of objects, which dramatically reduces the cost and improves the efficiency. In this work, a structural classification method, based on data extracted from color formation process on thin layer chromatography (TLC) plates through computer processing, was established for natural products. Representative natural products exhibited good clustering and separation according to the extracted color feature, and structure of natural products can be classified by the distribution region in the color system. This method provides structural information for typical types of natural products directly from the formed color on TLC, which is very efficient and make portable device-based structure analysis of natural products possible. In addition, a general mechanism of color formation was proposed. This method is free from special instrument, high-throughput, and would facilitate large-scale screening of bioactives from natural sources.

Enhancement of Antioxidant Activity in O/W Emulsion and Cholesterol-Reducing Capacity of Epigallocatechin by Derivatization with Representative Phytosterols

In this study, derivatization of epigallocatechin (EGC) by representative phytosterols (stigmasterol and β-sitosterol) was performed employing Steglich esterification. The structural identity and purity of epigallocatechin β-sitosterol (ESi) and epigallocatechin stigmasterol (ESt) were confirmed by NMR, FT-IR, and HPLC-MS. Further evaluation of ESi and ESt revealed their extraordinary antioxidant activities in O/W emulsion. Two different radical sources in oil or aqueous phase were applied to explore the antioxidant behavior in O/W emulsion. The mechanism was further investigated by fluorescent microscopy and transmission electron microscopy (TEM). Furthermore, incorporation of EGC with stigmasterol and β-sitosterol notably enhanced the cholesterol-reducing activity. TEM studies suggested the hydrogen bonding of EGC strengthened the aggregation network of ESi and ESt in the bile salt micelle. The exceptional properties of ESi and ESt signified their intriguing utilization in the food industry.

Antioxidant and Cytoprotective effects of Pyrola decorata H. Andres and its five phenolic components

Background

Pyrola decorata H. Andres, is exclusively distributed in China and a source of traditional Chinese herbal medicine Luxiancao for more than 2000 years. Here, we evaluated the antioxidant and cytoprotective effects of P. decorata and its five phenolic components (protocatechuic acid, gallic acid, hyperoside, 2′′-O-galloylhyperin, and quercetin), and discussed their antioxidant chemistry.

Methods

A lyophilized aqueous extract of P. decorata (LAEP) was prepared and analyzed with high-performance liquid chromatography (HPLC). LAEP and its five phenolic components were comparatively investigated using five antioxidant assays, including ferric-reducing antioxidant power, cupric ion-reducing antioxidant capacity, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide radical (PTIO^•)-scavenging, 1,1-diphenyl-2-picryl-hydrazl radical (DPPH^•)-scavenging, and 2,2′-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) radical (ABTS^+•)-scavenging activities. The reaction products of the five phenolic components with 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl radical (4-methoxy-TEMPO^•) were determined with ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UPLC-ESI-Q-TOF-MS/MS) analysis. LAEP and its five phenolic components were incubated with bone marrow-derived mesenchymal stem cells (bmMSCs) subjected to oxidative stress to demonstrate their cytoprotective effects with a flow cytometry assay.

Results

In the five antioxidant assays, LAEP and its five phenolic components dose-dependently increased the radical-scavenging (or reducing power) activities. However, the IC₅₀ values of hyperoside were consistently higher than those of 2′′-O-galloylhyperin. UPLC-ESI-Q-TOF-MS/MS analysis results indicated that the five phenolics could yield dimer products in the presence of 4-methoxy-TEMPO^• via the radical adduct formation (RAF) pathway. Flow cytometry assay results confirmed the cytoprotective activity of LAEP and its five phenolic components toward stressed bmMSCs. In particular, 2′′-O-galloylhyperin could more effectively reduce the percentage of damaged bmMSCs than hyperoside.

Conclusion

LAEP and its five phenolic components may undergo redox-based pathways (such as electron transfer and H⁺ transfer) and covalent-based pathway (i.e., RAF) to exhibit antioxidant activity. One consequence of RAF is the generation of phenolic-phenolic dimer. In both organic and aqueous media, 2′′-O-galloylhyperin exhibited higher redox-based antioxidant levels (or cytoprotective levels) than those with hyperoside. The differences could be attributed to 2′′-O-galloylation reaction.