Aucubin as a natural potential anti-acute hepatitis candidate: Inhibitory potency and hepatoprotective mechanism

Preparation techniques, structural features, and bioactivities of Eucommia ulmoides polysaccharides: A review

Eucommia ulmoides Oliv. (tu-chung), as a famous nature medical and edible plant, has the effect of tonifying liver and kidney, strengthening the function of the muscles and bones, and miscarriage prevention. Accumulating evidence has demonstrated that the polysaccharides from Eucommia ulmoides Oliv. (EUPs) are a kind of vital and representative biologically active macromolecules and have various health-promoting biological activities in vivo and in vitro, such as antioxidant activity, immunomodulatory activity, hypolipidemic and hypoglycemic activities, anti-inflammatory activities, anti-tumor activity, and among others. The review aims to comprehensively and systematically collate the recent research progress on extraction and purification methods, structural characteristics, biological activities, mechanism of action, structural modification, and toxicity of EUPs to support their therapeutic potential and health-care functions. New valuable insights for future research with EUPs were also proposed in the areas of structural characterization and pharmacological activities to promoting the development of therapeutic agents and functional foods.

Phlorizin from Lithocarpus litseifolius [Hance] Chun ameliorates FFA-induced insulin resistance by regulating AMPK/PI3K/AKT signaling pathway

BACKGROUND

Insulin resistance (IR) is the central pathophysiological feature in the pathogenesis of metabolic syndrome, obesity, type 2 diabetes mellitus (T2DM), hypertension, and dyslipidemia. As the main active ingredient in Lithocarpus litseifolius [Hance] Chun, previous studies have shown that phlorizin (PHZ) can reduce insulin resistance in the liver. However, the effect of phlorizin on attenuating hepatic insulin resistance has not been fully investigated, and whether this effect is related to AMPK remains unclear.

PURPOSE

The present study aimed to further investigate the effect of phlorizin on attenuating insulin resistance and the potential action mechanism.

METHODS

Free fatty acids (FFA) were used to induce insulin resistance in HepG2 cells. The effects of phlorizin and FFA on cell viability were detected by MTT analysis. Glucose consumption, glycogen synthesis, intracellular malondialdehyde (MDA), superoxide dismutase (SOD), total cholesterol (TC), and triglyceride (TG) contents were quantified after phlorizin treatment. Glucose uptake and reactive oxygen species (ROS) levels in HepG2 cells were assayed by flow cytometry. Potential targets and signaling pathways for attenuating insulin resistance by phlorizin were predicted by network pharmacological analysis. Moreover, the expression levels of proteins related to the AMPK/PI3K/AKT signaling pathway were detected by western blot.

RESULTS

Insulin resistance was successfully induced in HepG2 cells by co-treatment of 1 mM sodium oleate (OA) and 0.5 mM sodium palmitate (PA) for 24 h. Treatment with phlorizin promoted glucose consumption, glucose uptake, and glycogen synthesis and inhibited gluconeogenesis in IR-HepG2 cells. In addition, phlorizin inhibited oxidative stress and lipid accumulation in IR-HepG2 cells. Network pharmacological analysis showed that AKT1 was the active target of phlorizin, and the PI3K/AKT signaling pathway may be the potential action mechanism of phlorizin. Furthermore, western blot results showed that phlorizin ameliorated FFA-induced insulin resistance by activating the AMPK/PI3K/AKT signaling pathway.

CONCLUSION

Phlorizin inhibited oxidative stress and lipid accumulation in IR-HepG2 cells and ameliorated hepatic insulin resistance by activating the AMPK/PI3K/AKT signaling pathway. Our study proved that phlorizin played a role in alleviating hepatic insulin resistance by activating AMPK, which provided experimental evidence for the use of phlorizin as a potential drug to improve insulin resistance.

Liensinine alleviates sepsis-induced acute liver injury by inhibiting the NF-κB and MAPK pathways in an Nrf2-dependent manner

Sepsis remains a serious public health issue that needs to be addressed globally. Severe liver injury caused by sepsis increases the risk of death in patients with sepsis. Liensinine (Lie) is one of the primary active components in Plumula nelumbinis and has anti-inflammatory and antioxidant effects. Nevertheless, the effects of Lie on septic liver injury are unclear. This research investigated the protective effect of Lie (10, 20 and 40 mg/kg) on liver damage via intraperitoneal administration of LPS (10 mg/kg) to C57BL/6 mice. Lie was given through intraperitoneal injection once a day for five days. Mice were treated with LPS intraperitoneally for 6 h at 1 h after Lie administration on the last day. The results suggested that Lie could decrease AST and ALT levels in serum, ameliorate histopathological changes and inhibit cell apoptosis in mice with LPS-induced septic liver injury. In addition, Lie inhibited increases in the mRNA levels of TNF-α, IL-1β, iNOS and IL-6. Lie also increased the mRNA level of IL-10. Lie reduced the content of MDA, a marker of lipid peroxidation, and increased the activity of the antioxidant enzymes GSH-Px, CAT and SOD. Our results also showed that Lie could suppress the LPS-activated MAPK and NF-κB pathways and trigger the Nrf2 signaling pathway both in vitro and in vivo. Additionally, an Nrf2 inhibitor (ML385) weakened the suppressive effect of Lie on the MAPK and NF-κB pathways. Our results demonstrated that the suppressive effect of Lie on the MAPK and NF-κB pathways was partially reliant on activation of the Nrf2 pathway. In summary, these results indicate that Lie can improve inflammation and oxidative stress by activating Nrf2, which is a prospective therapeutic drug for alleviating septic liver injury.

Development of machine learning models using multi-source data for geographical traceability and content prediction of Eucommia ulmoides leaves

Rapid and scientific quality evaluation is a hot topic in the research of food and medicinal plants. With the increasing popularity of derivative products from Eucommia ulmoides leaves, quality and safety have attracted public attention. The present study utilized multi-source data and traditional machine learning to conduct geographical traceability and content prediction research on Eucommia ulmoides leaves. Explored the impact of different preprocessing methods and low-level data fusion strategy on the performance of classification and regression models. The classification analysis results indicated that the partial least squares discriminant analysis (PLS-DA) established by low-level fusion of two infrared spectroscopy techniques based on first derivative (FD) preprocessing was most suitable for geographical traceability of Eucommia ulmoides leaves, with an accuracy rate of up to 100 %. Through regression analysis, it was found that the preprocessing methods and data blocks applicable to the four chemical components were inconsistent. The optimal partial least squares regression (PLSR) model based on aucubin (AU), geniposidic acid (GPA), and chlorogenic acid (CA) had a residual predictive deviation (RPD) value higher than 2.0, achieving satisfactory predictive performance. However, the PLSR model based on quercetin (QU) had poor performance (RPD = 1.541) and needed further improvement. Overall, the present study proposed a strategy that can effectively evaluate the quality of Eucommia ulmoides leaves, while also providing new ideas for the quality evaluation of food and medicinal plants.

Aucubin protects against myocardial ischemia-reperfusion injury by regulating STAT3/NF-κB/HMGB-1 pathway

The main characteristics of the myocardial ischemia/reperfusion injury (MI/RI) are oxidative stress, apoptosis, and an inflammatory response. Aucubin (AU) is an iridoid glycoside that possesses various biological properties and has been discovered to demonstrate antioxidant and anti-inflammatory impacts in pathological processes, such as ischemia-reperfusion. The objective of this research was to investigate if AU treatment could mitigate myocardial inflammation and apoptosis caused by ischemia/reperfusion (I/R) in both laboratory and animal models, and to elucidate its underlying mechanism. By ligating the coronary artery on the left anterior descending side, a successful MI/RI rat model was created. Additionally, H9C2 cells were subjected to hypoxia/reoxygenation (H/R) in order to imitate the injury caused by ischemia/reperfusion (I/R). Furthermore, various concentrations of AU were administered to H9C2 cells or rats before H/R stimulation or myocardial I/R surgery, respectively. In vitro, the assessment was conducted on cardiac function, inflammatory markers, and myocardial pathology. In vivo, we examined the viability of cells, as well as factors related to apoptosis and oxidative stress. Furthermore, the presence of proteins belonging to the STAT3/NF-κB/HMGB1 signaling pathway was observed both in vivo and in vitro. AU effectively improved cardiomyocyte injury caused by H/R and myocardial injury caused by I/R. Furthermore, AU suppressed the production of reactive oxygen species and inflammatory molecules (TNF-alpha, IL-1β, and IL-6) and proteins associated with cell death (caspase-3 and Bax), while enhancing the levels of anti-inflammatory agents (IL-10) and the anti-apoptotic protein Bcl-2.AU mechanistically affected the phosphorylation of STAT3 at the Ser727 site and Tyr705 following H/R by modulating the signaling pathway involving signal transducer and activator of transcription 3 (STAT3)/nuclear factor-κB (NF-κB)/high mobility group box 1 (HMGB1), while also suppressing the nuclear translocation of NF-κB p65 and HMGB1 exonucleation. In conclusion, the use of AU treatment might offer protection against myocardial infarction and injury by reducing oxidative stress, suppressing apoptosis, and mitigating inflammation. The regulation of the STAT3/NF-κB/HMGB-1 pathway may contribute to this phenomenon by affecting STAT3 phosphorylation and controlling NF-κB and HMGB-1 translocation. Contributes to identifying possible objectives for myocardial ischemia/reperfusion damage.

The water-soluble subfraction from Artemisia argyi alleviates LPS-induced inflammatory responses via multiple pathways and targets in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

As a traditional Chinese medicine, Artemisia argyi has been used medicinally and eaten for more than 2000 years in China. It is widely reported in treating inflammatory diseases such as eczema, dermatitis, arthritis, allergic asthma and colitis. Although several studies claim that its volatile oil and organic reagent extracts have certain anti-inflammatory effects, the water-soluble fractions and molecular mechanisms have not been studied.

AIM OF THE STUDY

To evaluate the therapeutic effect of A. argyi water extract (AAWE) on lipopolysaccharide (LPS)-induced inflammatory responses and to identify the most effective water-soluble subfractions. Moreover, the relevant pharmacological and molecular mechanisms by which the active subfraction mitigates inflammation were further investigated.

MATERIALS AND METHODS

Firstly, RAW 264.7 cells stimulated with LPS were treated with AAWE (50, 100, and 200 μg/mL) or the water-soluble subfractions separated by D101 macroporous resin (AAWE1-AAWE4, 100 μg/mL), and NO production and mRNA levels of inflammatory genes were evaluated to determine the most effective water-soluble subfractions. Secondly, the chemical components of the active subfraction (AAWE4) were analyzed by UPLC-QTOF-MS. Thirdly, transcriptome and network pharmacology analysis, RT-qPCR and Western blotting assays were conducted to explore the underlying anti-inflammatory mechanism and active compounds of AAWE4. Subsequently, the binding ability of the potential active components in AAWE4 to the core targets was further determined by molecular docking. Eventually, the in vivo anti-inflammatory activity of AAWE4 (1.17, 2.34 and 4.68 g/kg, administered per day for 7 d) was evaluated in mice with LPS-induced systemic inflammation.

RESULTS

In this study, AAWE showed excellent anti-inflammatory effects, and its water-soluble subfraction AAWE4 exhibited the strongest inhibitory effect on NO concentration and inflammatory gene mRNA expression after LPS stimulation, indicating that it was the most effective subfraction. Thereafter, four main compounds in AAWE4 were confirmed or tentatively identified by UPLC-QTOF-MS, including three flavonoid glycosides and one phenolic acid. Furthermore, the transcriptome and network pharmacology analysis showed that AAWE4 inhibited inflammation via multiple pathways and multiple targets. Based on the RT-qPCR and Western blotting results, AAWE4 downregulated not only the p38, PI3K, CCL5, MMP9, AP-1, and BCL3 mRNA expression levels activated by LPS but also their upstream and downstream protein expression levels and protein phosphorylation (p-AKT/AKT, p-p38/p38, p-ERK/ERK, p-JNK/JNK). Moreover, four identified compounds (isochlorogenic acid A, vicenin-2, schaftoside and isoschaftoside) could significantly inhibit NO content and the overexpression of inflammatory factors TNF-α, IL-1β, iNOS and COX-2 mRNA induced by LPS, and the molecular docking confirmed the high binding activity of four active compounds with selected core targets (p38, AKT1, MMP9, and CCL5). In addition, the mRNA expression and immunohistochemical analysis showed that AAWE44 could inhibit lung inflammation via multiple pathways and multiple targets in vivo.

CONCLUSIONS

The findings of this study suggest that the water-soluble subfraction AAWE4 from A. argyi ameliorated the inflammation caused by LPS through multiple pathways and multiple targets in vitro and in vivo, providing scientific support for the medicinal use of A. argyi. Importantly, it shows that the A. argyi subfraction AAWE4 can be developed as an anti-inflammatory drug.

Extraction and Purification of Aucubin from Eucommia ulmoides Seed Draff in Natural Deep Eutectic Solvents Using Macroporous Resins

Aucubin (AU) is an active ingredient that exerts strong antioxidant and anti-inflammatory effects in the treatment of several diseases. In order to improve the efficiency of resource utilization of traditional biomass waste, Eucommia ulmoides seed-draff (EUSD) waste biomass was used as the raw material, and a series of deep eutectic solvents were selected to evaluate the extraction efficiency of aucubin from EUSD. A response surface experiment was designed based on a single-factor experiment to optimize the extract conditions. The results showed that the best conditions for aucubin extraction were an HBD-HBA ratio of 2.18, a liquid-solid ratio of 46.92 mL/g, a water percentage of 37.95%, a temperature of 321.03 K, and an extraction time of 59.55 min. The maximum amount of aucubin was 156.4 mg/g, which was consistent with the theoretical value (156.8 mg/g). Then, the performance of 12 resins for adsorption and desorption was contrasted. The results revealed that HPD950 resin exhibited the best performance, with an adsorption capacity of 95.2% and a desorption capacity of 94.3%. Additionally, the pseudo-second-order model provided the best match to the kinetics data, the Langmuir model provided the best fit to the isotherm data, and adsorption was a beneficial, spontaneous, exothermic, and physical process. In the recyclability test, the HPD950 resin had great potential and excellent sustainability in aucubin recovery. In the antioxidant activity study, the aucubin extract exerted a strong antioxidant ability with scavenging capabilities for four free radicals. Furthermore, the antifungal activity study found that the aucubin extract exhibited a good antifungal effect against 5 tested pathogens. The research results can provide a theoretical basis for the extraction of high-value components from waste biomass by deep eutectic solvent and a certain application value for the development and utilization of natural aucubin products.