Interaction between lactic acid bacteria and Polygonatum sibiricum saponins and its application to microencapsulated co-delivery

This study aimed to investigate the interaction between L.casei and L.bulgaricus with Polygonatum sibiricum saponins (PSS) and to explore the co-microencapsulation to reduce their loss rate during storage and consumption. 1% PSS was added to the culture broth, and it was found that the growth and metabolism of the strains were accelerated, especially in the compound probiotic group, indicating that PSS has potential for prebiotics. LC-MS observed significant differences in the composition and content of saponins in PSS. The metabolomics results suggest that the addition of PSS resulted in significant changes in the metabolites of probiotics. In addition, it was found that the combination of probiotics and PSS may have stronger hypoglycemic ability (ɑ-glucosidase, HepG2). Finally, a co-microencapsulated delivery system was constructed using zein and isomaltooligosaccharide. This system can achieve more excellent resistance of probiotics and PSS in gastrointestinal fluids, effectively transporting both to the small intestine.

Analysis of gut microbiota metabolites of platycodin D and activity verification

As the main saponin component of Platycodon grandiflorum A.DC, Platycodin D has been reported to have an anti-obesity effect. Due to poor oral absorption, the intestinal microflora usually transforms saponins into potential bioactive substances. In this study, we profiled the metabolic changes of platycodin D by incubating it with intestinal microflora extracted from mice feces subjected to either a standard control diet or a high-fat diet. A UPLC-LTQ-Orbitrap-MS method was used for rapid analysis of the metabolic profile of platycodin D. A total of 10 compounds were identified 9 of which were assessed to be metabolized by intestinal microflora. Dehydroxylation and deglycosylation were the major metabolic process of platycodin D. The metabolic profile of platycodin D biotransformed by intestinal microflora was elucidated based on the metabolite information. Platycodin D and its metabolites had anti-inflammatory effects in LPS-stimulated RAW 264.7 cells. Only platycodin D could alleviate lipid accumulation in FFA-treated HepG2 cells.

[Uncovering the molecular mechanisms behind steroidal saponin accumulation in Liriope muscari (Decne.) Baily through transcriptome sequencing and bioinformatics analysis]

The leaves and roots of Liriope muscari (Decne.) Baily were subjected to high-throughput Illumina transcriptome sequencing. Bioinformatics analysis was used to investigate the enzyme genes and key transcription factors involved in regulating the accumulation of steroidal saponins, which are the main active ingredient in L. muscari. These analyses aimed to reveal the molecular mechanism behind steroidal saponin accumulation. The sequencing results of L. muscari revealed 31 enzymes, including AACT, CAS, DXS and DXR, that are involved in the synthesis of steroidal saponins. Among these enzymes, 16 were in the synthesis of terpenoid skeleton, 3 were involved in the synthesis of sesquiterpene and triterpene, and 12 were involved in the synthesis of steroidal compound. Differential gene expression identified 15 metabolic enzymes coded by 34 differentially expressed genes (DEGs) in the leaves and roots, which were associated with steroidal saponin synthesis. Further analysis using gene co-expression patterns showed that 14 metabolic enzymes coded by 31 DEGs were co-expressed. In addition, analysis using gene co-expression analysis and PlantTFDB's transcription factor analysis tool predicted the involvement of 8 transcription factors, including GAI, PIF4, PIL6, ERF8, SVP, LHCA4, NF-YB3 and DOF2.4, in regulating 6 metabolic enzymes such as DXS, DXR, HMGR, DHCR7, DHCR24, and CAS. These eight transcription factors were predicted to play important roles in regulating steroidal saponin accumulation in L. muscari. Promoter analysis of these transcription factors indicated that their main regulatory mechanisms involve processes such as abscisic acid response, drought-induction stress response and light response, especially abscisic acid responsive elements (ABRE) response and MYB binding site involved in drought-inducibility (MBS) response pathway. Furthermore, qRT-PCR analysis of these eight key transcription factors demonstrated their specific differences in the leaves and roots.

A new insight into material basis of rhizoma Paridis saponins in alleviating pain

ETHNOPHARMACOLOGICAL RELEVANCE

Paris polyphylla, as a traditional Chinese herbal medicine, was often used to relieve inflammation and pain. Rhizoma Paridis saponins (RPS) as the main active components of Paris polyphylla have excellent analgesic effects.

AIM OF THE STUDY

Determine the analgesic material basis of RPS.

MATERIALS AND METHODS

LC-MS/MS was used to analyze RPS, plasma after intravenous injection of RPS, and oral administration of RPS. H22 plantar pain model was established to explore the analgesic material basis of RPS. Moreover, correlation analysis, network pharmacology, RT-PCR and molecular docking were applied in this research.

RESULTS

RPS had dose-dependently analgesic effects in acetic acid- and formalin-induced pain models. LC-MS/MS detection indicated that diosgenin as the metabolite of RPS mainly distributed in brain tissues. The addition of antibiotics increased the anti-tumor effect of RPS, but reduced its analgesic effect. Network pharmacology, RT-PCR and molecular docking showed that diosgenin exerted its analgesic effect through SRC and Rap1 signaling pathway.

CONCLUSION

Diosgenin exhibited analgesic effects, while saponins had good anti-tumor effects in RPS. This discovery provided a better indication for the later application of RPS in anti-tumor and analgesic settings.

Trichoplusia ni Transcriptomic Responses to the Phytosaponin Aglycone Hederagenin: Sex-Related Differences

Many plant species, particularly legumes, protect themselves with saponins. Previously, a correlation was observed between levels of oleanolic acid-derived saponins, such as hederagenin-derived compounds, in the legume Medicago truncatula and caterpillar deterrence. Using concentrations that reflect the foliar levels of hederagenin-type saponins, the sapogenin hederagenin was not toxic to 4th instar caterpillars of the cabbage looper Trichoplusia ni nor did it act as a feeding deterrent. Female caterpillars consumed more diet than males, presumably to obtain the additional nutrients required for oogenesis, and are, thus, exposed to higher hederagenin levels. When fed the hederagenin diet, male caterpillars expressed genes encoding trypsin-like proteins (LOC113500509, LOC113501951, LOC113501953, LOC113501966, LOC113501965, LOC113499659, LOC113501950, LOC113501948, LOC113501957, LOC113501962, LOC113497819, LOC113501946, LOC113503910) as well as stress-responsive (LOC113503484, LOC113505107) proteins and cytochrome P450 6B2-like (LOC113493761) at higher levels than females. In comparison, female caterpillars expressed higher levels of cytochrome P450 6B7-like (LOC113492289). Bioinformatic tools predict that cytochrome P450s could catalyze the oxygenation of hederagenin which would increase the hydrophilicity of the compound. Expression of a Major Facilitator Subfamily (MFS) transporter (LOC113492899) showed a hederagenin dose-dependent increase in gene expression suggesting that this transporter may be involved in sapogenin efflux. These sex-related differences in feeding and detoxification should be taken into consideration in insecticide evaluations to minimize pesticide resistance.

Characterization and Applications of Permeabilized Hepatocytes in Drug Discovery

Hepatocytes are one of the most physiologically relevant in vitro liver systems for human translation of clearance and drug-drug interactions (DDI). However, the cell membranes of hepatocytes can limit the entry of certain compounds into the cells for metabolism and DDI. Passive permeability through hepatocytes can be different in vitro and in vivo, which complicates the human translation. Permeabilized hepatocytes offer a useful tool to probe mechanistic understanding of permeability-limited metabolism and DDI. Incubation with saponin of 0.01% at 0.5 million cells/mL and 0.05% at 5 million cells/mL for 5 min at 37°C completely permeabilized the plasma membrane of hepatocytes, while leaving the membranes of subcellular organelles intact. Permeabilized hepatocytes maintained similar enzymatic activity as intact unpermeabilized hepatocytes and can be stored at -80°C for at least 7 months. This approach reduces costs by preserving leftover hepatocytes. The relatively low levels of saponin in permeabilized hepatocytes had no significant impact on the enzymatic activity. As the cytosolic contents leak out from permeabilized hepatocytes, cofactors need to be added to enable metabolic reactions. Cytosolic enzymes will no longer be present if the media are removed after cells are permeabilized. Hence permeabilized hepatocytes with and without media removal may potentially enable reaction phenotyping of cytosolic enzymes. Although permeabilized hepatocytes work similarly as human liver microsomes and S9 fractions experimentally requiring addition of cofactors, they behave more like hepatocytes maintaining enzymatic activities for over 4 h. Permeabilized hepatocytes are a great addition to the drug metabolism toolbox to provide mechanistic insights.

Immunofluorescence analysis of human eosinophils

A prominent inflammatory cell type in allergic diseases is the eosinophil, a granulated white blood cell that releases pro-inflammatory cytokines. Eosinophil-derived cytokines, including interleukin-9 (IL-9) and interleukin-13 (IL-13), can skew the immune response towards an allergic phenotype. Unfortunately, it is challenging to immunolabel and collect quantifiable images of eosinophils given their innate autofluorescence and ability to nonspecifically bind to antibodies. Hence, it is important to optimize permeabilization, blocking, and imaging conditions for eosinophils. Here, we show enhanced protocols to ensure that measured immunofluorescence represents specific immunolabelling. To test this, eosinophils were purified from human blood, adhered to glass coverslips, stimulated with or without platelet-activating factor (PAF), fixed with paraformaldehyde, and then permeabilized with Triton X-100 or saponin. Cells were then blocked with goat serum or human serum and incubated with antibodies labelling cytokines (IL-9 and IL-13) and secretory organelles (CD63 for crystalloid granules and transferrin receptor [TfnRc] for recycling endosomes). Carefully selected isotype controls were used throughout, and cells were imaged using Deltavision super-resolution microscopy. Intensities of fluorescent probes were quantified using Volocity software. Our findings show that permeabilization with saponin, blockage with human serum, and using concentrations of antibodies up to 10 μg/ml allowed us to detect marked differences in fluorescence intensities between isotypes and test antibodies. With the achievement of sufficient qualitative and quantitative measures of increased test probe intensity compared to respective isotypes, these results indicate that our protocol allows for optimal immunolabelling of eosinophils. Using this protocol, future studies may provide further insights into trafficking mechanisms within this important inflammatory cell type.

Astragaloside IV mitigates hypoxia-induced cardiac hypertrophy through calpain-1-mediated mTOR activation

BACKGROUND

Astragaloside IV (AsIV), a key functioning element of Astragalus membranaceus, has been recognized for its potential cardiovascular protective properties. However, there is a need to elucidate the impacts of AsIV on myocardial hypertrophy under hypoxia conditions and its root mechanisms.

PURPOSE

This study scrutinized the influence of AsIV on cardiac injury under hypoxia, with particular emphasis on the role of calpain-1 (CAPN1) in mediating mTOR pathways.

METHODS

Hypoxia-triggered cardiac hypertrophy was examined in vivo with CAPN1 knockout and wild-type C57BL/6 mice and in vitro with H9C2 cells. The impacts of AsIV, 3-methyladenine, and CAPN1 inhibition on hypertrophy, autophagy, apoptosis, [Ca2+]i, and CAPN1 and mTOR levels in cardiac tissues and H9C2 cells were investigated.

RESULTS

Both AsIV treatment and CAPN1 knockout mitigated hypoxia-induced cardiac hypertrophy, autophagy, and apoptosis in mice and H9C2 cells. Moreover, AsIV, 3-methyladenine, and CAPN1 inhibition augmented p-mTOR level but reduced [Ca2+]i and CAPN1 level. Additionally, lentivirus-mediated CAPN1 overexpression in H9C2 cells exacerbated myocardial hypertrophy, apoptosis, and p-mTOR inhibition under hypoxia. Specifically, AsIV treatment reversed the impacts of increased CAPN1 expression on cardiac injury and the inhibition of p-mTOR.

CONCLUSION

These findings suggest that AsIV may alleviate cardiac hypertrophy under hypoxia by attenuating apoptosis and autophagy through CAPN1-mediated mTOR activation.

[Total saponins of Panax japonicus alleviates CCl4-induced acute liver injury in rats by regulating the PI3K/AktNF-κB signaling pathway]

OBJECTIVE

To investigate the protective effect of total saponins of Panax japonicus (TSPJ) against CCl4-induced acute liver injury (ALI) in rats and explore the underlying pharmacological mechanisms.

METHODS

Male SD rat models of CCl4-induced ALI were given intraperitoneal injections of distilled water, 100 mg/kg biphenyl bisabololol, or 50, 100, and 200 mg/kg TSPJ during modeling (n=8). Liver functions (AST, ALT, TBil and ALP) of the rats were assessed and liver pathologies were observed with HE staining. Immunohistochemistry was used to detect the expressions of PI3K/Akt/NF-κB signaling pathway molecules in liver tissue; ELISA was used to determine the levels of T-SOD, GSH-Px, and MDA. Western blotting was performed to detect the expression levels of PI3K-Akt and SIRT6-NF-κB pathways in the liver tissue.

RESULTS

Network pharmacological analysis indicated that the key pathways including PI3K/Akt mediated the therapeutic effect of TSPJ on ALI. In the rat models of ALI, treatments with biphenyl bisabololol and TSPJ significantly ameliorated CCl4-induced increase of serum levels AST, ALT, ALP, TBil and MDA and decrease of T-SOD and GSH-Px levels (all P < 0.01). The rat models of ALI showed significantly increased expression of p-NF-κB (P < 0.01), decreased expressions of PI3K, p-Akt and SIRT6 proteins, and elevated expression levels of p-NF-κB, TNF-α and IL-6 proteins in the liver, which were all significantly improved in the treatment groups (P < 0.05 or 0.01).

CONCLUSION

TSPJ can effectively alleviate CCl4-induced ALI in rats by suppressing inflammatory responses and oxidative stress in the liver via regulating the PI3K/Akt and SIRT6/NF-κB pathways.

Exploration of the immuno-adjuvant effect and mechanism of Anemoside B4 through network pharmacology and experiment verification

BACKGROUND

Extensive investigation has been undertaken about the utilization of saponin adjuvants in vaccines intended for veterinary and human applications. AB4 is the main constituent of the traditional Chinese medicine, Pulsatilla chinensis (Bunge) Regel, and has immunomodulatory activity. However, there is a paucity of reports on AB4 as a potential adjuvant.

PURPOSE

The objective of this work was to clarify the adjuvant role of AB4 and the molecular mechanisms that underlie its immunomodulatory actions.

STUDY DESIGN AND METHODS

The immunomodulatory effects of AB4 were investigated using network pharmacological analyses. These effects were validated by evaluating the developmental status of the immune organs and by using the following techniques: ELISA for the quantification of serum-specific antibodies to determine immune-related cytokine levels; the MTS method for the assessment of proliferative activity of splenic lymphocytes; flow cytometry to analyze lymphocyte and dendritic cell activation status; and western blotting for mechanistic analysis at the protein level.

RESULTS

The network pharmacological analysis predicted a total of 52 targets and 12 pathways for AB4 to exert immunomodulatory effects. In a mouse model with immunity to OVA, the introduction of AB4 resulted in the enhancement of immunological organ growth and maturation, elevation of blood antibodies targeting OVA, and amplification of the production of cytokines associated with Th1 and Th2 immune responses. Additionally, the administration of AB4 resulted in a notable augmentation of lymphocyte proliferation and an elevation in the CD4+/CD8+ T lymphocyte ratios. Furthermore, the administration of AB4 enhanced the maturation process of DCs in the draining LNs and increased the production of co-stimulatory factors and MHC II molecules. AB4 induces the upregulation of TLR4 and IKK proteins, as well as the phosphorylation of NF-κB p65 protein within the TLR4/NF-κB signaling cascade, while concurrently suppressing the expression of IκBα protein.

CONCLUSION

The specific immunoadjuvant effects of AB4 have been demonstrated to modulate the growth and maturation of immune organs and enhance the secretion and cellular activity of pertinent immune molecules. The utilization of network pharmacology, combined within and in vivo vitro assays, clarified the adjuvant function of AB4, which potentially involves the regulation of the TLR4/NF-κB signaling pathway.

Application of fenugreek in ruminant feed: implications for methane emissions and productivity

Background

Human demand for meat and dairy products will increase as a result of economic development and population growth, and the farming of ruminants, such as cattle and sheep, will also increase. Methane (CH4) emission from the enteric fermentation of ruminant livestock is a major source of greenhouse gas emissions and a significant contributor to global warming. Meanwhile, growth performance is often limited and animals are more vulnerable to diseases in high-density, intensive farming, greatly reducing livestock productivity, so developing ways to reduce CH4 emissions and improve ruminant productivity has become a research hotspot. Studies have reported that fenugreek (Trigonella foenum-graecum L.) as feed additives have the potential to reduce ruminant methane and improve the productivity. However, systematic reviews of such studies are lacking.

Methodology

In this review, databases of Google Scholar, Web of Science, PubMed, Scopus and Science Direct were used for the literature search. The initial keywords search was fenugreek or Trigonella foenum-graecum L. For more focused search, we added terms such as methane, rumen fermentation, growth, milk production and antioxidants. All were done for ruminants. The literature that conforms to the theme of this article is selected, summarized, and finally completed this article.

Results

By regulating the rumen microbiome (suppressing protozoans, methanogenic bacteria, and fungi), fenugreek can lower CH4 emissions according to many in vitro anaerobic fermentation experiments. Fenugreek secondary metabolites (saponins and tannins) are responsible for this impact, but it is still unclear exactly how they work. Therefore, more long-term in vivo experiments are needed to verify its efficacy. Fenugreek is also rich in alkaloids, amino acids, flavonoids, saponins and phenolic acids. These compounds have been shown to have beneficial effects on ruminant growth, lactation, and total antioxidant capacity. Therefore, fenugreek has a great opportunity to develop into a new green feed additive.

Conclusions

This review provides a summary of the effect of fenugreek and its bioactive compounds on rumen fermentation, CH4 emissions and production performance by ruminants. In addition, based on the available data, the possible biochemical pathway of fenugreek to reduce CH4 emissions in ruminants was described. Overall, the livestock feed industry has the opportunity to develop natural, environmentally-friendly feed additives based on fenugreek.

Panax notoginseng saponins alleviate diabetic retinopathy by inhibiting retinal inflammation: Association with the NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetic retinopathy (DR) is a neurovascular disease that causes blindness in adults and is the most serious and common complication of diabetes mellitus. Retinal inflammation is an early stage of DR, and it is believed to play a crucial role in the development of DR. Panax notoginseng saponins (PNS) are the major active constituent in the main root of P. notoginseng, and they exhibit various biological activities, including anti-inflammatory, antioxidant, neuroprotective, and immunomodulatory functions. However, the protective effects and underlying mechanisms of PNS against DR remain unclear.

AIM OF THE STUDY

This study aimed to investigate the alleviation effects of PNS on DR and the mechanisms involved. Furthermore, it intended to explore the major components that exert efficacy in vivo.

MATERIALS AND METHODS

Streptozotocin (STZ) was administered intraperitoneally to Sprague Dawley rats, and PNS was administered orally for 1 month after 2 months of STZ injection. The morphological structure of the retina and retinal acellular capillaries were assessed via hematoxylin and eosin (H&E) staining assay. The disruption of the blood-retinal barrier (BRB) was detected through Evans blue dye leakage assay, and retinal leukocyte adhesion was achieved via fluorescein isothiocyanate-coupled concanavalin A lectin labeling assay. Immunofluorescence staining and Western blot assays were conducted to detect the expression of tight junction proteins, adhesion molecules, and the ionized calcium-binding adapter molecule-1 (Iba-1) in the retina. Enzyme-linked immunosorbent assay was performed to detect the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in serum. In addition, the protein expression levels of nuclear factor (NF)-κB p65, phosphorylated IκB kinase (p-IKK), phosphorylated NF-κB inhibitor (p-IκB), and phosphorylated NF-κB p65 (p-p65) were measured using Western blot assay. The ocular tissue distribution of PNS in normal and diabetic rats was determined through ultra-performance liquid chromatography-tandem mass spectrometry. The in vitro anti-inflammatory effects of PNS, notoginsenoside (NGR1), ginsenoside Rg1, Re, Rb1, and Rd (GRg1, GRe, GRb1, and GRd) were evaluated on human Müller (MIO-M1) cells.

RESULTS

PNS increased the reduction in retinal inner nuclear layer thickness, reduced the increase in retinal acellular capillaries, and attenuated elevated BRB disruption by upregulating the decrease in protein expression of claudin-1 and occludin. Furthermore, PNS significantly abrogated microglial cell activation and reversed the increase in leukocyte adhesion by downregulating the increase in the protein expression of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. Moreover, PNS reduced the elevated levels of TNF-α, IL-6, and IL-1β in serum and inhibited the increased protein expression of p-IKK, p-IκB, and p-p65, and the nuclear translocation of p65. The tissue distribution results revealed that NGR1, GRg1, GRe, GRb1, and GRd were detected in the ocular tissue, while GRg1 and GRb1 were found at the highest levels compared with the other components. The cellular results showed that PNS, NGR1, GRg1, GRe, GRb1, and GRd suppressed the development of cellular inflammatory responses by inhibiting the activation of the NF-κB signaling pathway in MIO-M1 cells and that their anti-inflammatory effects were comparable.

CONCLUSION

PNS suppressed retinal inflammation by inhibiting the activation of the NF-κB signaling pathway, alleviating DR. GRg1 and GRb1 may be the primary components that exert anti-inflammatory effects in vivo.

Calenduloside E ameliorates non-alcoholic fatty liver disease via modulating a pyroptosis-dependent pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Non-alcoholic fatty liver disease (NAFLD) is a prevalent chronic liver condition that can have multiple underlying causes. There are no satisfactory chemical or biological drugs for the treatment of NAFLD. Longyasongmu, the bark and root of Aralia elata (Miq.) Seem, is used extensively in traditional Chinese medicine (TCM) and has been used in treating diverse liver diseases including NAFLD. Based on Aralia elata (Miq.) Seem as the main ingredient, Longya Gantai Capsules have been approved for use in China for the treatment of acute hepatitis and chronic hepatitis. Calenduloside E (CE), a natural pentacyclic triterpenoid saponin, is a significant component of saponin isolated from the bark and root of Aralia elata (Miq.) Seem. However, the role and mechanism of anti-NAFLD effects of CE is still unclear.

AIM OF THE STUDY

The objective of this study was to examine the potential mechanisms underlying the protective effect of CE on NAFLD.

MATERIALS AND METHODS

In this study, an NAFLD model was established by Western diet in apoE-/- mice, followed by treatment with various doses of CE (5 mg/kg, 10 mg/kg). The anti-NAFLD effect of CE was assessed by the liver injury, lipid accumulation, inflammation, and pro-fibrotic phenotype. The mechanism of CE in ameliorating NAFLD was studied through transcriptome sequencing (RNA-seq). In vitro, the mouse hepatocytes (AML-12) were stimulated in lipid mixtures with CE and performed the exploration and validation of the relevant pathways using Western blot, immunofluorescence, etc. RESULTS: The findings revealed a significant improvement in liver injury, lipid accumulation, inflammation, and pro-fibrotic phenotype upon CE administration. Furthermore, RNAseq analysis indicated that the primary pathway through which CE alleviates NAFLD involves pyroptosis-related inflammatory cascade pathways. Furthermore, it was observed that CE effectively suppressed inflammasome-mediated pyroptosis both in vivo and in vitro. Remarkably, the functional enrichment analysis of RNA-seq data revealed that the PI3K-Akt signaling pathway is the primarily Signaling transduction pathway modulated by CE treatment. Subsequent experimental outcomes provided further validation of CE's ability to hinder inflammasome-mediated pyroptosis through the inhibition of PI3K/AKT/NF-κB signaling pathway.

CONCLUSIONS

These findings present a novel pharmacological role of CE in exerting anti-NAFLD effects by inhibiting pyroptosis signaling pathways.

Panax notoginseng saponins inhibits oxidative stress- induced human nucleus pulposus cell apoptosis and delays disc degeneration in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Panax notoginseng (Burk) F. H. Chen has been a popular traditional Chinese medicine with a long history of treating low back pain. Its main active ingredient, Panax notoginseng saponins (PNS), can be found in several Chinese patent medicines that are frequently used to treat blood stasis type low back pain. Intervertebral disc degeneration (IDD) is the most common cause of back pain, and the injection of PNS has been used to relieve IDD-induced back pain in clinical practice. Despite its effectiveness, the exact mechanisms of action for PNS injections remain unclear.

AIM OF THE STUDY

IDD as a consequence of aging involves apoptosis of nucleus pulposus (NP) cells and imbalanced degradation of extracellular matrix (ECM) induced by several factors including oxidative stress. We hypothesized that PNS may have a therapeutic effect on IDD via inhibiting apoptosis of NP cells and degradation of ECM under oxidative stress.

MATERIALS AND METHODS

In this study, network pharmacology was initially employed to predict the targets of PNS against IDD. Subsequently, commercial PNS was analyzed by high-performance liquid chromatography to confirm the ingredients for in vitro and in vivo experiments. In vitro experiments were conducted on human nucleus pulposus (HNP) cells, including CCK-8, RT-PCR, Western blot, immunofluorescence staining, autophagic flux detection, and TUNEL assay. In vivo experiments were also performed on rats with IDD of tail discs induced by annular fibrosus needle puncture, which involved MRI, HE staining, and immunohistochemistry.

RESULTS

Our study demonstrated the theoretical targets of PNS against IDD, including Caspase 3, MMP13, Akt, and autophagy, based on network pharmacology. Subsequently, in vitro experiments revealed that PNS attenuated cellular apoptosis of NP by suppressing the expression of cleaved-caspase 3 and the ratio of Bax/Bcl-2 under H2O2 stimulation. Autophagy was also inhibited by PNS treatment, and the protective effect was abolished with rapamycin, an autophagy inducer, indicating that autophagy inhibition was involved in the protective effect of PNS on IDD. Furthermore, Akt/mTOR pathway activation was observed in HNP cells responding to H2O2 with PNS treatment, which played a role in autophagy downregulation. PNS was also shown to promote the expression of anabolic genes such as COL2A1 and ACAN while inhibiting the expression of catabolic gene MMP13 in HNP cells. In addition, the in vivo study revealed that PNS treatment could ameliorate IDD in a puncture-induced rat tail model. The development of IDD was significantly reduced, and there was decreased MMP13 expression, as well as increased COL2A1 protein expression in NP tissues.

CONCLUSION

Our study showed that PNS could protect HNP cells against apoptosis via autophagy inhibition and ameliorate disc degeneration in vivo, indicating its potential to be a therapeutic agent for IDD.

Hepatoprotective efficacy and interventional mechanism of the panaxadiol saponin component in high-fat diet-induced NAFLD mice

Dietary administration is a promising strategy for intervention in non-alcoholic fatty liver disease (NAFLD). Our research team has identified a biologically active component, the panaxadiol saponin component (PDS-C) isolated from total saponins of panax ginseng, which has various pharmacological and therapeutic functions. However, the efficacy and mechanism of PDS-C in NAFLD were unclear. This study aimed to elucidate the hepatoprotective effects and underlying action mechanism of PDS-C in NAFLD. Mice were fed a high-fat diet (HFD) for 8 weeks to induce NAFLD and treated with PDS-C and metformin as the positive control for 12 weeks. PDS-C significantly alleviated liver function, hepatic steatosis and blood lipid levels, reduced oxidative stress and inflammation in NAFLD mice. In vitro, PDS-C has been shown to reduce lipotoxicity and ROS levels while enhancing the antioxidant and anti-inflammatory capabilities in HepG2 cells induced by palmitic acid. PDS-C induced AMPK phosphorylation, leading to upregulation of the Nrf2/HO1 pathway expression and downregulation of the NFκB protein level. Furthermore, our observations indicate that PDS-C supplementation improves insulin resistance and glucose homeostasis in NAFLD mice, although its efficacy is not as pronounced as metformin. In conclusion, these results demonstrate the hepatoprotective efficacy of PDS-C in NAFLD and provide potential opportunities for developing functional products containing PDS-C.

Unraveling the mechanisms of Fenugreek seed for managing different gynecological disorders: steroidal saponins and isoflavones revealed as key bioactive metabolites

This study employed network pharmacology-based analysis and reverse molecular docking to investigate the molecular targets and pathways associated with gynecological disorders, particularly those related to steroidal hormones and their receptors, and the potential therapeutic effects of fenugreek (Trigonella foenum-graecum L.) constituents. The STITCH 5.0 database was utilized to identify potential molecular targets, and a compound-target network was constructed. The main targets associated with gynecological disorders included estrogen receptor beta (ESR2), estrogen-related receptor gamma (GPER1), oxytocin receptor (OXTR), progesterone receptor (PGR), prolactin receptor (PRLR), and several enzymes involved in sex hormone biosynthesis. Additionally, network topological analysis revealed that specific compounds, such as quercetin, luteolin, genistein, and vitexin, had significant interactions with the identified targets. Reverse molecular docking analysis confirmed the interactions between the identified compounds and target proteins where quercetin, luteolin, genistein, 4'-methylgenistein, trigoneoside IIB, diosgenin, and vitexin possessed the highest combined docking scores, indicating their multi-target nature. The results highlighted the potential of steroidal saponins, isoflavones, and flavones as active constituents of fenugreek with implications for lactation, reproductive processes, and estrogenic activity. The chemical profiling of saponin-enriched and flavonoid-enriched fractions using UPLC/MS/MS further supported the presence of these bioactive compounds. In an animal model study, the steroidal saponins-enriched fraction of fenugreek seed exhibited a significant increase in the body weight of lactating female rats and serum prolactin levels while the flavonoids-enriched fraction showed an increase in serum estradiol levels and improved the histological structure of ovaries.

Astragalus saponins protect against extrahepatic and intrahepatic cholestatic liver fibrosis models by activation of farnesoid X receptor

ETHNOPHARMACOLOGICAL RELEVANCE

Cholestatic Liver Fibrosis (CLF) is a hepatobiliary disease that typically arises as a late-stage complication of cholestasis, which can have multiple underlying causes. There are no satisfactory chemical or biological drugs for CLF. Total Astragalus saponins (TAS) are considered to be the main active constituents of the traditional Chinese herb Astragali Radix (AR), which has the obvious improvement effects for treating CLF. However, the mechanism of anti-CLF effects of TAS is still unclear.

AIM OF THE STUDY

The present study was undertaken to investigate the therapeutic effects of TAS against bile duct ligation (BDL) and 3, 5-diethoxycarbonyl-1,4-dihydroxychollidine (DDC) -induced CLF models and to reveal the potential mechanism to support its clinic use with scientific evidence.

MATERIALS AND METHODS

In this study, BDL-induced CLF rats were treated with TAS (20 mg/kg, 40 mg/kg) and DDC-induced CLF mice were treated with 56 mg/kg TAS. The therapeutic effects of TAS on extrahepatic and intrahepatic CLF models were evaluated by serum biochemical analysis, liver histopathology and hydroxyproline (Hyp). Thirty-nine individual bile acids (BAs) in serum and liver were quantified by using UHPLC-Q-Exactive Orbitrap HRMS. qRT-PCR, Western blot and immunohistochemistry analysis were used to measure the expression of liver fibrosis and ductular reaction markers, inflammatory factors and BAs related metabolic transporters, along with nuclear receptor farnesoid X receptor (FXR).

RESULTS

The serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBiL), direct bilirubin (DBiL) and contents of liver Hyp were dose-dependently improved after treatment for TAS in BDL and DDC- induced CLF models. And the increased levels of ALT and AST were significantly improved by total extract from Astragali radix (ASE) in BDL model. The liver fibrosis and ductular reaction markers, α-smooth muscle actin (α-SMA) and cytokeratin 19 (CK19), were significantly ameliorated in TAS group. And the liver expression of inflammatory factors: interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β) were significantly decreased after TAS treatment. In addition, TAS significantly ameliorated taurine-conjugated BAs (tau-BAs) levels, particularly α-TMCA, β-TMCA and TCA contents in serum and liver, which correlated with induced expressions of hepatic FXR and BAs secretion transporters. Furthermore, TAS significantly improved short heterodimer partner (SHP), cholesterol 7α-hydroxylase (Cyp7a1), Na+ taurocholate cotransport peptide (NTCP) and bile-salt export pump (BSEP) mRNA and protein expression.

CONCLUSIONS

TAS exerted a hepatoprotective effect against CLF by ameliorating liver injury, inflammation and restoring the altered tau-BAs metabolism to produce a positive regulatory effect on FXR-related receptors and transporters.

Adventitious root culture of Lessertia frutescens for the production of triterpenoid saponins and polysaccharides

Lessertia frutescens is a perennial shrub of commercial importance in South Africa, but the scarcity of plant resources has limited current product production. In this study, to provide an alternative approach for obtaining L. frutescens material, adventitious roots (ARs) were induced from sterilized seedlings and cultured in a suspension culture system. During this process, selection tests were conducted to find a suitable auxin and its concentration for AR induction and a suitable basal medium for AR growth and metabolite accumulation; a kinetic study was then performed to constructure kinetic models. The results showed that compared to other auxins and concentrations, indole-3-butyric acid at 3 mg/L was suitable for increasing the number and length of ARs during AR induction. In AR suspension culture, Schenk and Hildebrandt (SH) was better than other basal media, and the maximum AR fresh (86.9 g/L) or dry weight (5.5 g/L), total triterpenoid saponin (92.6 mg/g DW), and polysaccharide (114.7 mg/g DW) contents were determined in the 1.5×SH medium. In addition, AR biomass and metabolite contents reached the maximum on day 42. The kinetic models for AR growth and triterpenoid and polysaccharide production were constructed, providing the basis for further optimization of culture conditions and large-scale culture.

Total saponins from Panax japonicus attenuate acute alcoholic liver oxidative stress and hepatosteatosis by p62-related Nrf2 pathway and AMPK-ACC/PPARα axis in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Panax japonicus (T. Nees) C.A. Mey. (PJ) has been used as a tonic traditional Chinese medicine (TCM) for years. Based on its meridian tropism in liver, spleen, and lung, PJ was popularly used to enhance the function of these organs. It is originally recorded with detoxicant effect on binge drink in Ben Cao Gang Mu Shi Yi, a persuasive Chinese materia medica. And binge dink has a close relationship with alcoholic liver disease (ALD). Hence, it's meaningful to investigate whether PJ exerts liver protection against binge drink toxicity.

AIM OF THE STUDY

This investigation was carried out not only to emphasize the right recognition of total saponins from PJ (SPJ), but also to study on its sober-up effectiveness and defensive mechanism against acute alcoholic liver injury in vivo and in vitro.

MATERIALS AND METHODS

SPJ constituents were verified by HPLC-UV analysis. In vivo, acute alcoholic liver oxidative stress and hepatosteatosis were established by continuous ethanol gavage to C57BL/6 mice for 3 days. SPJ was pre-administered for 7 days to investigate its protective efficacy. Loss of righting reflex (LORR) assay was employed to assess anti-inebriation effect of SPJ. Transaminases levels and hematoxylin and eosin (H&E) staining were measured to indicate the alcoholic liver injury. Antioxidant enzymes were measured to evaluate the oxidative stress degree in liver. Measurement of hepatic lipid accumulation was based on Oil Red O staining. Levels of inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA). In vitro, HepG2 cells were treated with ethanol for 24 h, and SPJ was pre-administered for 2 h. 2,7-dichlorofluorescein diacetate (DCFH-DA) was used as a probe to indicate reactive oxygen species (ROS) generation. Nrf2 activation was verified by the favor of specific inhibitor, ML385. The nuclear translocation of Nrf2 was indicated with immunofluorescence analysis. Proteins expressions of related pathways were determined by Western blotting.

RESULTS

Oleanane-type saponins are the most abundant constituents of SPJ. In this acute model, SPJ released inebriation of mice in a dose dependent manner. It decreased levels of serum ALT and AST, and hepatic TG. Besides, SPJ inhibited CYP2E1 expression and reduced MDA level in liver, with upregulations of antioxidant enzymes GSH, SOD and CAT. p62-related Nrf2 pathway was activated by SPJ with downstream upregulations of GCLC and NQO1 in liver. AMPK-ACC/PPARα axis was upregulated by SPJ to alleviate hepatic lipidosis. Hepatic IL-6 and TNF-α levels were downregulated by SPJ, which indicated a regressive lipid peroxidation in liver. In HepG2 cells, SPJ reduced ethanol-exposed ROS generation. Activated p62-related Nrf2 pathway was verified to contribute to the alleviation of alcohol-induced oxidative stress in hepatic cells.

CONCLUSION

This attenuation of hepatic oxidative stress and steatosis suggested the therapeutic value of SPJ for ALD.

Saponin of Aralia taibaiensis promotes angiogenesis through VEGF/VEGFR2 signaling pathway in cerebral ischemic mice

ETHNOPHARMACOLOGICAL RELEVANCE

Aralia taibaiensis is known for its ability to promote blood circulation and dispel blood stasis, activate meridians and remove arthralgia. The saponins of Aralia taibaiensis (sAT) are the main active components that are often used to treat cardiovascular and cerebrovascular diseases. However, it has not been reported whether sAT can improve ischemic stroke (IS) by promoting angiogenesis.

AIM OF THE STUDY

In this study, we investigated the potential of sAT to promote post-ischemic angiogenesis in mice and determined the underlying mechanism through in vitro experiments.

METHODS

To establish the middle cerebral artery occlusion (MCAO) mice model in vivo. First of all, we examined the neurological function, brain infarct volume, and degree of brain swelling in MCAO mice. We also observed pathological changes in brain tissue, ultrastructural changes in blood vessels and neurons, and the degree of vascular neovascularization. Additionally, we established the oxygen-glucose deprivation/reoxygenation (OGD/R) -human umbilical vein endothelial cells (HUVECs) model in vitro to detect the survival, proliferation, migration and tube formation of OGD/R HUVECs. Finally, we verified the regulatory mechanism of Src and PLCγ1 siRNA on sAT promoting angiogenesis by cell transfection technique.

RESULTS

In the cerebral ischemia-reperfusion mice, sAT distinctly improved the cerebral infarct volume, brain swelling degree, neurological dysfunction, and brain histopathological morphology due to cerebral ischemia/reperfusion injury. It also increased the double positive expression of BrdU and CD31 in brain tissue, promoted the release of VEGF and NO and decreased the release of NSE and LDH. In the OGD/R HUVECs, sAT significantly improved cell survival, proliferation, migration and tube formation, promoted the release of VEGF and NO, and increased the expression of VEGF, VEGFR2, PLCγ1, ERK1/2, Src and eNOS. Surprisingly, the effect of sAT on angiogenesis was inhibited by Src siRNA and PLCγ1 siRNA in OGD/R HUVECs.

CONCLUSION

The results proved that sAT promotes angiogenesis in cerebral ischemia-reperfusion mice and its mechanism is to regulate VEGF/VEGFR2 and then regulate Src/eNOS and PLCγ1/ERK1/2.

LPS-induced macrophage exosomes promote the activation of hepatic stellate cells and the intervention study of total astragalus saponins combined with glycyrrhizic acid

Huangqi decoction, also known as Huangqi Liuyi decoction, was first recorded in the prescriptions of the Bureau of Taiping People's Welfare Pharmacy. It comprises astragalus and licorice, which is a commonly used prescription in traditional Chinese medicine for the clinical treatment of chronic liver disease, especially liver cirrhosis. Total astragalus saponins (AST) is the main component of astragalus, and glycyrrhizic acid (GA) is the main component of licorice. In this study, normal macrophage exosomes were extracted, and the exosomes incubated with lipopolysaccharides (LPS) and those incubated with LPS + AST + GA were co-cultured with JS1 cells (hepatic stellate cell line). The survival rate and the activation of key signaling pathways of JS1 cells in each group were detected and compared. We found that the co-culture of LPS-induced macrophage exosomes with JS1 cells could significantly increase the expression levels of Collagen-1 (Col-1) and Alpha smooth muscle actin (α-SMA)in JS1 cells. However, a significant reversal effect was observed after pretreatment with AST combined with GA. Further evaluation found that the expression levels of phospho (p)-Smad2 and p-Smad3 in the JS1 cells were significantly increased after macrophages were induced with LPS, whereas pretreatment with AST + GA could significantly decrease the expression levels of p-Smad2 and p-Smad3. Preliminary results of this study indicated that LPS-induced macrophage exosomes can promote the activation of hepatic stellate cells, and the pretreatment of AST combined with GA can exert a significant intervention effect. In this study, the new mechanism of anti-hepatic fibrosis effect of traditional Chinese medicine components of Huangqi Decoction was analyzed from the perspective of exosomes.

Jujuboside B post-treatment attenuates PM2.5-induced lung injury in mice

Fine particulate matter (PM2.5) is an air pollutant that causes severe lung injury. We investigated the effects of Jujuboside B (JB), a component of Zizyphi Spinosi Semen, on lung toxicity caused by PM2.5, and we identified the mechanism of its protective effect. Lung injury in an animal model was induced by intratracheal administration of a PM2.5 suspension. After 2 days of PM2.5 pretreatment, mice were administered JB via the tail vein three times over a 2-day period. JB significantly reduced the histological lung damage as well as the lung wet/dry weight ratio. JB also considerably reduced PM2.5-induced autophagy dysfunction, apoptosis, inflammatory cytokine levels, and the number of PM2.5-induced lymphocytes in the bronchial alveolar fluid. We conclude that by regulating TLR2, 4-MyD88, and mTOR-autophagy pathways, JB exerts a protective effect on lung injury. Thus, JB can be used as a potential therapeutic agent for PM2.5-induced lung damage.

Asperosaponin VI protects alcohol-induced hepatic steatosis and injury via regulating lipid metabolism and ER stress

BACKGROUND

Asperosaponin VI (AVI) is a natural triterpenoid saponin isolated from Dipsacus asper Wall with documented anti-inflammatory and bone protective effects. Our previous work reported that AVI protects the liver of septic mice from acute inflammatory damage. In this paper, we further explored the protective effect and the potential mechanisms of AVI in alcoholic fatty liver disease (AFLD).

METHODS

The Lieber-Decarli model was constructed to evaluate the effect of AVI on AFLD in C57BL/6 J mice. Additional in vitro work was performed to investigate HepG2 cells exposed to alcohol, then analyzed the degree of liver injury by detecting the ALT and AST levels both in the liver and serum. H&E staining and Sirius red staining were used to evaluate the histopathology variations in the liver. Further, observe lipid droplets in the cytoplasm by Oil Red O staining. We detected the expression of inflammatory cytokines with qualitative PCR; ROS, MDA, SOD, and GSH-px levels were analyzed to observe oxidative stress. Finally, exploring the activation of AMPK signaling pathway by real-time PCR and Western blotting.

RESULTS

Histological examination of liver tissue combined with serum ALT and AST levels showed a significant protective effect of AVI against alcoholic liver injury in AFLD mice. Compared with the model group, AVI evidently improved antioxidant capacity, reduced inflammatory response and lipid accumulation both in vitro and in vivo. For mechanically, it was found that AVI up-regulated phosphorylation level of AMP-activated protein kinase (AMPK) and inhibited the endoplasmic reticulum stress (ER) pathway in AFLD.

CONCLUSION

AVI protects mice from alcohol-induced hepatic steatosis and liver injury through activating AMPK signaling and repress ER stress, suggesting that it might be a potential therapeutic agent for AFLD.

Multi-omics analysis reveals the mechanism of action of ophiopogonin D against pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive lung disease with limited therapeutic strategies. Therefore, there is an urgent need to search for safe and effective drugs to treat this condition. Ophiopogonin D (OP-D), a steroidal saponin compound extracted from ophiopogon, possesses various pharmacological properties, including anti-inflammatory, antioxidant, and antitumor effects. However, the potential pharmacological effect of OP-D on pulmonary fibrosis remains unknown.

PURPOSE

The aim of this study was to investigate whether OP-D can improve pulmonary fibrosis and to explore its mechanism of action.

METHODS

The effect of OP-D on pulmonary fibrosis was investigated in vitro and in vivo using a mouse model of IPF induced by bleomycin and an in vitro model of human embryonic lung fibroblasts induced by transforming growth factor-β1 (TGF-β1). The mechanism of action of OP-D was determined using multi-omics techniques and bioinformatics.

RESULTS

OP-D attenuated epithelial-mesenchymal transition and excessive deposition of extracellular matrix in the lungs, promoted the apoptosis of lung fibroblasts, and blocked the differentiation of lung fibroblasts into myofibroblasts. The multi-omics techniques and bioinformatics analysis revealed that OP-D blocked the AKT/GSK3β pathway, and the combination of a PI3K/AKT inhibitor and OP-D was effective in alleviating pulmonary fibrosis.

CONCLUSION

This study demonstrated for the first time that OP-D can reduce lung inflammation and fibrosis. OP-D is thus a potential new drug for the prevention and treatment of pulmonary fibrosis.

Total Astragalus saponins can reverse type 2 diabetes mellitus-related intestinal dysbiosis and hepatic insulin resistance in vivo

Objective

Intestinal flora homeostasis in rats with type 2 diabetes mellitus (T2DM) was evaluated to explore the effects of total Astragalus saponins (TAS) on hepatic insulin resistance (IR).

Methods

Six-week-old male Sprague-Dawley rats were fed high-fat and high-sugar diet for 4 weeks and intraperitoneally injected with streptozotocin to induce T2DM, and they were then randomly divided into control, model, metformin, and TAS groups. Stool, serum, colon, and liver samples were collected after 8 weeks of drug administration for relevant analyses.

Results

TAS reduced fasting blood glucose, 2-hour postprandial blood glucose, area under the curve of oral glucose tolerance test, glycated serum protein, homeostasis model assessment of insulin resistance, total cholesterol, triglyceride, and low-density lipoprotein cholesterol levels in T2DM rats but increased insulin, C-peptide, and high-density lipoprotein cholesterol levels. Moreover, TAS improved the morphology and structure of liver and colon tissues and improved the composition of the intestinal microbiome and bacterial community structure at different taxonomic levels. In addition, TAS increased the protein expression of hepatic IRS-1, PI3K, PDK1, and p-AKT and decreased the protein expression of p-GSK-3β. Meanwhile, TAS increased the mRNA expression of liver PDK1, PI3K, and GS and decreased the mRNA expression of GSK-3β.

Conclusion

TAS can ameliorate T2DM-related abnormal glucose and blood lipid metabolism, intestinal dysbiosis, and IR.

Astragaloside IV reduces lung injury in lethal sepsis via promoting treg cells expansion and inhibiting inflammatory responses

Sepsis is a systemic inflammatory response syndrome caused by an infection progressing to sepsis-associated organ failure (such as lung injury). Our previous review revealed that Astragaloside IV (ASI-IV), one of the primary bioactive ingredients in Astragalus membranaceus (Fisch) Bge (Huang-Qi), had been shown to exert anti-inflammatory and immunomodulatory effects. Nevertheless, it is still unclear whether ASI-IV could attenuate septic lung injury via activating regulatory T-cells (Tregs). This study was designed to evaluate the therapeutic potential of ASI-IV on sepsis-induced lung injury and to further explore its underlying mechanism. In the murine models of cecal ligation and puncture (CLP) and lipopolysaccharide (LPS) induced sepsis, ASI-IV can markedly improve the survival rate and reduce inflammatory lung injury, protect mice against exacerbated inflammatory responses by decreasing myeloid cell infiltration and down-regulating IL-6 and TNF-α in lung tissue. Meanwhile, Treg cell-related gene expression, including Foxp3 and IL-10, significantly increased after ASI-IV treatment. Furthermore, ASI-IV notably promoted the differentiation of naïve CD4+ T cells into T regulatory cells without obviously affecting Th1 and Th17 differentiation. Our results indicated that ASI-IV could attenuate septic lung injury by promoting Treg cell expansion and inhibiting inflammatory responses. It represents a promising agent for the treatment of sepsis.

Tomato root-associated Sphingobium harbors genes for catabolizing toxic steroidal glycoalkaloids

IMPORTANCE

Saponins are a group of plant specialized metabolites with various bioactive properties, both for human health and soil microorganisms. Our previous works demonstrated that Sphingobium is enriched in both soils treated with a steroid-type saponin, such as tomatine, and in the tomato rhizosphere. Despite the importance of saponins in plant-microbe interactions in the rhizosphere, the genes involved in the catabolism of saponins and their aglycones (sapogenins) remain largely unknown. Here we identified several enzymes that catalyzed the degradation of steroid-type saponins in a Sphingobium isolate from tomato roots, RC1. A comparative genomic analysis of Sphingobium revealed the limited distribution of genes for saponin degradation in our saponin-degrading isolates and several other isolates, suggesting the possible involvement of the saponin degradation pathway in the root colonization of Sphingobium spp. The genes that participate in the catabolism of sapogenins could be applied to the development of new industrially valuable sapogenin molecules.

Hemolysis by Saponin Is Accelerated at Hypertonic Conditions

Saponins are a large group of organic amphiphilic substances (surfactants) mainly extracted from herbs with biological activity, considered as one of the main ingredients in numerous remedies used in traditional medicine since ancient times. Anti-inflammatory, antifungal, antibacterial, antiviral, antiparasitic, antitumor, antioxidant and many other properties have been confirmed for some. There is increasing interest in the elucidation of the mechanisms behind the effects of saponins on different cell types at the molecular level. In this regard, erythrocytes are a very welcome model, having very simple structures with no organelles. They react to changing external conditions and substances by changing shape or volume, with damage to their membrane ultimately leading to hemolysis. Hemolysis can be followed spectrophotometrically and provides valuable information about the type and extent of membrane damage. We investigated hemolysis of erythrocytes induced by various saponin concentrations in hypotonic, isotonic and hypertonic media using measurements of real time and end-point hemolysis. The osmotic pressure was adjusted by different concentrations of NaCl, manitol or a NaCl/manitol mixture. Unexpectedly, at a fixed saponin concentration, hemolysis was accelerated at hypertonic conditions, but was much faster in NaCl compared to mannitol solutions at the same osmotic pressure. These findings confirm the colloid-osmotic mechanism behind saponin hemolysis with pore formation with increasing size in the membrane.

Saikosaponin D attenuates inflammatory response and cell apoptosis of lipopolysaccharide-induced lung epithelial cells

BACKGROUND

Acute lung injury (ALI) is a prevalent complication of sepsis with high mortality rate. Saikosaponin D (SSD) is a triterpenoid saponin that has been reported to alleviate sepsis-triggered renal injury in mice. Nonetheless, the therapeutic effect of SSD on sepsis-evoked ALI is unclarified.

METHODS

Lipopolysaccharide (LPS) from Escherichia coli 055:B5 was utilized to stimulate lung epithelial cell line MLE-12. A mouse model of sepsis was established. CCK-8 assay was employed for determining cytotoxicity. ELISA was utilized for determining proinflammatory cytokine production. Flow cytometry and western blotting were implemented for evaluating cell apoptosis. Hematoxylin-eosin staining was conducted for histologic analysis of murine lung tissues.

RESULTS

SSD alleviated LPS-triggered inflammation and cell apoptosis of MLE-12 cells. SSD treatment ameliorated the pathological damages, inflammatory response, and cell apoptosis in the lungs of septic mice.

CONCLUSION

SSD protects against sepsis-triggered ALI by inhibiting inflammation and cell apoptosis in MLE-12 cells and septic mouse mice.

Evolutionary roles of polyploidization-derived structural variations in the phenotypic diversification of Panax species

Genomic structural variations (SVs) are widespread in plant and animal genomes and play important roles in phenotypic novelty and species adaptation. Frequent whole genome duplications followed by (re)diploidizations have resulted in high diversity of genome architecture among extant species. In this study, we identified abundant genomic SVs in the Panax genus that are hypothesized to have occurred through during the repeated polyploidizations/(re)diploidizations. Our genome-wide comparisons demonstrated that although these polyploidization-derived SVs have evolved at distinct evolutionary stages, a large number of SV-intersecting genes showed enrichment in functionally important pathways related to secondary metabolites, photosynthesis and basic cellular activities. In line with these observations, our metabolic analyses of these Panax species revealed high diversity of primary and secondary metabolites both at the tissue and interspecific levels. In particular, genomic SVs identified at ginsenoside biosynthesis genes, including copy number variation and large fragment deletion, appear to have played important roles in the evolution and diversification of ginsenosides. A further herbivore deterrence experiment demonstrated that, as major triterpenoidal saponins found exclusively in Panax, ginsenosides provide protection against insect herbivores. Our study provides new insights on how polyploidization-derived SVs have contributed to phenotypic novelty and plant adaptation.

The NAC Transcription Factor PgNAC41-2 Gene Involved in the Regulation of Ginsenoside Biosynthesis in Panax ginseng

Ginseng (Panax ginseng C.A. Meyer) is a perennial herb of the Araliaceae family, a traditional and valuable Chinese herb in China. The main active component of ginseng is ginsenoside. The NAC transcription factors belong to a large family of plant-specific transcription factors, which are involved in growth and development, stress response and secondary metabolism. In this study, we mapped the NAC gene family on 24 pairs of ginseng chromosomes and found numerous gene replications in the genome. The NAC gene PgNAC41-2, found to be highly related to ginsenoside synthesis, was specifically screened. The phylogeny and expression pattern of the PgNAC41-2 gene were analyzed, along with the derived protein sequence, and a structure model was generated. Furthermore, the PgNAC41-2 gene was cloned and overexpressed by a Rhizobium rhizogenes mediated method, using ginseng petioles as receptor material. The saponin content of the transformed material was analyzed to verify the function of the NAC transcription factor in ginseng. Our results indicate that the PgNAC41-2 gene positively regulates the biosynthesis of saponins.

Tenuifolin in the prevention of Alzheimer's disease-like phenotypes: Investigation of the mechanisms from the perspectives of calpain system, ferroptosis, and apoptosis

Polygala tenuifolia was documented to calm the mind and promote wisdom. However, its underlying mechanisms are still unclear. This study aimed to investigate the mechanisms underlying the effects of tenuifolin (Ten) on Alzheimer's disease (AD)-like phenotypes. We first applied bioinformatics methods to screen the mechanisms of P. tenuifolia in the treatment of AD. Thereafter, the d-galactose combined with Aβ1-42 (GCA) was applied to model AD-like behaviors and investigate the action mechanisms of Ten, one active component of P. tenuifolia. The data showed that P. tenuifolia actioned through multi-targets and multi-pathways, including regulation of synaptic plasticity, apoptosis, and calcium signaling, and so forth. Furthermore, in vitro experiments demonstrated that Ten prevented intracellular calcium overload, abnormal calpain system, and down-regulation of BDNF/TrkB signaling induced by GCA. Moreover, Ten suppressed oxidative stress and ferroptosis in HT-22 cells induced by GCA. Calpeptin and ferroptosis inhibitor prevented the decrease of cell viability induced by GCA. Interestingly, calpeptin did not interrupt GCA-induced ferroptosis in HT-22 cells but blocked the apoptosis. Animal experiments further demonstrated that Ten prevented GCA-induced memory impairment in mice and increased synaptic protein expression while reducing m-calpain expression. Ten prevents AD-like phenotypes through multiple signaling by inhibiting oxidative stress and ferroptosis, maintaining the stability of calpain system, and suppressing neuronal apoptosis.

Characterization and protein engineering of glycosyltransferases for the biosynthesis of diverse hepatoprotective cycloartane-type saponins in Astragalus membranaceus

Although plant secondary metabolites are important source of new drugs, obtaining these compounds is challenging due to their high structural diversity and low abundance. The roots of Astragalus membranaceus are a popular herbal medicine worldwide. It contains a series of cycloartane-type saponins (astragalosides) as hepatoprotective and antivirus components. However, astragalosides exhibit complex sugar substitution patterns which hindered their purification and bioactivity investigation. In this work, glycosyltransferases (GT) from A. membranaceus were studied to synthesize structurally diverse astragalosides. Three new GTs, AmGT1/5 and AmGT9, were characterized as 3-O-glycosyltransferase and 25-O-glycosyltransferase of cycloastragenol respectively. AmGT1_G146V/I variants were obtained as specific 3-O-xylosyltransferases by sequence alignment, molecular modelling and site-directed mutagenesis. A combinatorial synthesis system was established using AmGT1/5/9, AmGT1_G146V/S and the reported AmGT8 and AmGT8_A394F . The system allowed the synthesis of 13 astragalosides in Astragalus root with conversion rates from 22.6% to 98.7%, covering most of the sugar-substitution patterns for astragalosides. In addition, AmGT1 exhibited remarkable sugar donor promiscuity to use 10 different donors, and was used to synthesize three novel astragalosides and ginsenosides. Glycosylation remarkably improved the hepatoprotective and SARS-CoV-2 inhibition activities for triterpenoids. This is one of the first attempts to produce a series of herbal constituents via combinatorial synthesis. The results provided new biocatalytic tools for saponin biosynthesis.

Toxicological effects of Saponin on the free larval stages of Schistosoma mansoni, infection rate, some biochemical and molecular parameters of Biomphalaria alexandrina snails

Saponins have been used as biopesticides. The objective of the present study is to investigate the toxic effects of Saponin against Biomphalaria alexandrina snails. Results showed that Saponin exhibited a molluscicidal activity against adult B. alexandrina snails at LC₅₀ (70.05 mg/l) and had a larvicidal effect on the free larval stages of Schistosoma mansoni. To evaluate the lethal effects, snails were exposed to either LC₁₀ (51.8 mg/l) or LC₂₅ (60.4 mg/l) concentrations of Saponin. The survival, the infection rates, protein, albumin, and total fat levels were decreased, while glucose levels were increased in exposed snails compared to control snails. Also, these concentrations significantly raised Malondialdehyde (MDA) and Glutathione S Transferase (GST) levels, whereas reduced Superoxide dismutase (SOD) activity and the total antioxidant capacity (TAC) in exposed snails. Furthermore, these concentrations resulted in endocrine disruptions where it caused a significant increase in testosterone (T) level; while a significant decrease in Estradiol (E2) levels were noticed. As for Estrogen (E) level, it was increased after exposure to LC₁₀ Saponin concentration while after exposure to LC₂₅ concentration, it was decreased. Also, LC₁₀ and LC₂₅ concentrations of Saponin caused a genotoxic effect and down-regulation of metabolic cycles in the snails. In conclusion, Saponins caused deleterious effects on the intermediate host of schistosomiasis mansoni. Therefore, B. alexandrina snails could be used as models to screen the toxic effects of Saponins in the aquatic environment and if it was used as a molluscicide, it should be used cautiously and under controlled circumstances.

Achyranthoside D attenuates chondrocyte loss and inflammation in osteoarthritis via targeted regulation of Wnt3a

BACKGROUND

Achyranthes bidentata Blume (A. bidentata) is a common Chinese herb used to treat osteoarthritis (OA). Achyranthoside D (Ach-D) is a glucuronide saponin isolated from A. bidentata.

PURPOSE

To assess the mechanisms of action of Ach-D and its effects on OA.

METHODS

The effects of Ach-D were evaluated in rats underwent anterior cruciate ligament transection (ACLT) with medial meniscectomy (MMx) and in interleukin (IL)-1β-induced chondrocytes. Histological changes in rat cartilage tissues were detected using Safranin O-Fast green and haematoxylin-eosin staining. Immunohistochemical staining, qRT-PCR, ELISA, immunoblotting, and immunofluorescence were conducted to examine cartilage degeneration-related and inflammation-related factor expression. CCK-8, LDH assay, and EdU staining were performed to detect chondrocyte death.

RESULTS

Ach-D dose-dependently reduced the Osteoarthritis Research Society International (OARSI) scores, alleviated cartilage injury, and decreased the serum concentrations of CTX-II and COMP in ACLT-MMx models. Ach-D increased the expression levels of collagen II and aggrecan and decreased the levels of cartilage degeneration-related proteins, ADAMTS-5, MMP13, and MMP3, in rat cartilage tissues. Additionally, nod-like receptor protein 3 (NLRP3)-related inflammation was reduced by Ach-D, as shown by the significantly inhibited expression levels of NLRP3, ASC, GSDMD, IL-6, TNF-α, IL-1β, and IL-18 in rat cartilage tissues. In primary rat chondrocytes, Ach-D protected against IL-1β-induced viability loss and LDH release. Wnt3a is the target protein of Ach-D. Mechanistically, Ach-D alleviated OA by inhibiting Wnt signalling.

CONCLUSION

ACH-D may reduce inflammation and cartilage degeneration by inhibiting the Wnt signalling pathway, thereby reducing OA.

Advances in the Biosynthesis and Molecular Evolution of Steroidal Saponins in Plants

Steroidal saponins are an important type of plant-specific metabolite that are essential for plants' responses to biotic and abiotic stresses. Because of their extensive pharmacological activities, steroidal saponins are also important industrial raw materials for the production of steroidal drugs. In recent years, more and more studies have explored the biosynthesis of steroidal saponins in plants, but most of them only focused on the biosynthesis of their molecular skeleton, diosgenin, and their subsequent glycosylation modification mechanism needs to be further studied. In addition, the biosynthetic regulation mechanism of steroidal saponins, their distribution pattern, and their molecular evolution in plants remain unclear. In this review, we summarized and discussed recent studies on the biosynthesis, molecular regulation, and function of steroidal saponins. Finally, we also reviewed the distribution and molecular evolution of steroidal saponins in plants. The elucidation of the biosynthesis, regulation, and molecular evolutionary mechanisms of steroidal saponins is crucial to provide new insights and references for studying their distribution, diversity, and evolutionary history in plants. Furthermore, a deeper understanding of steroidal saponin biosynthesis will contribute to their industrial production and pharmacological applications.

Specific Enriched Acinetobacter in Camellia Weevil Gut Facilitate the Degradation of Tea Saponin: Inferred from Bacterial Genomic and Transcriptomic Analyses

Beneficial gut bacteria can enhance herbivorous arthropod adaptation to plant secondary compounds (PSMs), and specialist herbivores provide excellent examples of this. Tea saponin (TS) of Camellia oleifera is triterpenoids toxic to seed-feeding weevil pest, Curculio chinensis (CW). Previous studies disclosed that Acinetobacter, which was specific enriched in the CW's gut, was involved in helping CW evade TS toxicity of C. oleifera. However, it is still not clear whether Acinetobacter is associated with other anti-insect compounds, and the molecular mechanism of Acinetobacter degradation of TS has not been clarified. To address these questions, we explored the relationship between host plant toxin content and Acinetobacter of CW gut bacteria. Results demonstrated that TS content significantly affected the CW gut microbiome structure and enriched bacteria functional for TS degradation. We further isolated Acinetobacter strain and conducted its genome and transcriptome analyses for bacterial characterization and investigation on its role in TS degradation. Biological tests were carried out to verify the ability of the functional bacterium within CW larvae to detoxify TS. Our results showed that TS-degrading bacteria strain (Acinetobacter sp. AS23) genome contains 47 genes relating to triterpenoids degradation. The AS23 strain improved the survival rate of CW larvae, and the steroid degradation pathway could be the key one for AS23 to degrade TS. This study provides the direct evidence that gut bacteria mediate adaptation of herbivorous insects to phytochemical resistance. IMPORTANCE Microorganism is directly exposed to the plant toxin environment and play a crucial third party in herbivores gut. Although previous studies have proved the existence of gut bacteria that help CWs degrade TS, the specific core flora and its function have not been explored. In this study, we investigated the correlation between the larva gut microbiome and plant secondary metabolites. Acinetobacter genus was the target flora related to TS degradation. There were many terpenoids genes in Acinetobacter sp. AS23 genome. Results of transcriptome analysis and biological tests suggested that steroid degradation pathway be the key pathway of AS23 to degrade TS. This study not only provides direct evidence that gut microbes mediate the rapid adaptation of herbivorous insects to phytochemical resistance, but also provides a theoretical basis for further research on the molecular mechanism of intestinal bacteria cooperating with pests to adapt to plant toxins.

Ginseng total saponins and Fuzi total alkaloids exert antidepressant-like effects in ovariectomized mice through BDNF-mTORC1, autophagy and peripheral metabolic pathways

BACKGROUND

Shenfu decoction (SFD) is a classic Chinese medicine prescription that has a strong cardiotonic effect. The combination of ginseng (the dried root of Panax ginseng C. A. Meyer) and Fuzi (processed product of sub-root of Aconitum carmichaeli Debx), the main constituents of SFD, has been reported to improve the pharmacological effect of each other. Moreover, research has shown that the main active components of SFD, ginseng total saponins (GTS) and Fuzi total alkaloids (FTA), have antidepressant activity. However, the effects of these ingredients on depressive-like behavior induced by ovariectomy, a model of menopausal depression, have not been studied.

PURPOSE

Our research aims to elucidate the antidepressant-like effects of GTS and FTA compatibility (GF) in ovariectomized mice and the potential mechanisms.

METHODS

To elucidate the antidepressant-like effects of GF in mice in ovariectomy condition, behavioral tests were performed after 7 days of intragastric administration of different doses of GF. Underlying molecular mechanisms of CREB-BDNF, BDNF-mTORC1 and autophagy signaling were detected by western blotting, serum metabolites were examined by UPLC-QE plus-MS and dendritic spine density was determined by Golgi-Cox staining.

RESULTS

GF remarkably decreased the immobility time in the forced swim test. GF also increased levels of pCREB/CREB, BDNF, Akt, mTORC1 and p62 in the prefrontal cortex and hippocampus, as well as decreased LC3-II/LC3-I in the prefrontal cortex and hippocampus of ovariectomized mice. Furthermore, 15 serum differential metabolites (9 of which are lipids and lipid molecules) were identified by metabonomics. Next, the antidepressant-like effects of GF was blocked by rapamycin, an inhibitor of mTORC1. The antidepressant actions of GF on levels of pCREB, mTORC1, LC3-Ⅱ/LC3-Ⅰ and p62 in the prefrontal cortex and the levels of BDNF, Akt, mTORC1 and p62 in the hippocampus were inhibited by rapamycin, and the dendritic spines density was also regulated.

CONCLUSION

GF has antidepressant effects in ovariectomized mice, and like other antidepressants, these effects involve activation of BDNF-mTORC1, autophagy regulation and consequent effects on hippocampal synaptic plasticity. Moreover, metabolomic results suggest that GF also has effects on peripheral lipid profiles that may provide potential biomarkers for these antidepressant-like effects. These results indicate that GF is worthy of further exploration as a promising pharmaceutical treatment for depression. This study provides a new direction for the development of new indications for traditional Chinese medicine compounds.

Changes in immune responses, gene expression, and life table parameters of Helicoverpa armigera Hübner fed on a diet containing the saponin of tea plant, Camellia sinensis

Saponins cause mortality in insects by reducing food absorption and movement in the gut, which may be used to exploit the control of insect pests. In the current study, tea seed saponin (TSS) was extracted and then added to the artificial diets of Helicoverpa armigera. Pre-ovipositional period of the TSS-treated individuals increased while longevity and fecundity decreased compared to control. There was a significant reduction of the treated individuals in the life table parameters of TSS-treated Individuals including net reproduction rate (R₀ ), intrinsic rate of population increase (r), finite rate of increase (λ), and gross reproduction rate (GRR). Also, we found that saponin suppressed the immune system by reducing the total hemocyte count, immune-related gene expression, and phenoloxidase activity. Our results demonstrated a lower expression of cecropin gene in the treated larvae with TSS while no significant differences were observed in attacin gene. Our results clearly showed that feeding of H. armigera larvae in the diet containing TSS significantly reduced demographic parameters, forced insects to obtain more time to complete one generation, and caused vulnerabilities against pathogens. These discrepancies alleviated nutrient uptake of the larvae and disrupted their feeding and growth. Hence, a proper formulation with a desirable concentration would be prepared and applied in the fields suffering H. armigera damage to monitor insecticidal efficiency of TSS.

Astragaloside IV ameliorates diet-induced hepatic steatosis in obese mice by inhibiting intestinal FXR via intestinal flora remodeling

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a major clinical and public health burden worldwide with no established pharmacological therapy. Changes in the intestinal flora and associated metabolite bile acids (BAs) have been described in NAFLD. Astragaloside IV (AS-IV) is a low drug permeability saponin with protective effects against multiple diseases. However, the specific mechanism underlying the involvement of AS-IV in the regulation of NAFLD is yet to be clarified.

PURPOSE

This study aimed to investigate the effect of AS-IV on NAFLD and explore whether intestinal flora was involved.

METHODS

The effect of AS-IV was evaluated on high-fat diet-fed mice. Real-time PCR, immunohistochemistry, immunofluorescence, and biochemical analyses were performed. 16S rRNA gene sequencing and UPLC-TQMS were used to determine the alterations in the intestinal flora and concentration of BAs. Fecal microbiota transplantation (FMT) and intestine-specific farnesoid X receptor (FXR) knockout were also performed.

RESULTS

AS-IV treatment alleviated diet-induced metabolic impairments, particularly hepatic steatosis. These changes occurred in the setting of decreased intestinal bile salt hydrolase (BSH)-expressing flora. Further analysis showed that the reduced BSH activity increased intestinal tauro-β-muricholic acid levels, an inhibitor of intestinal FXR. Inhibition of intestinal FXR signaling by AS-IV was accompanied by decreased expression of intestinal fibroblast growth factor 15 and subsequent hepatic FXR activation as well as increased glucagon-like peptide-1 and decreased ceramide production, all of which contribute to the inhibition of sterol regulatory element-binding protein-1c-mediated hepatic steatosis. Furthermore, intestine-specific Fxr knockout and FMT further demonstrated an FXR- and intestinal flora-dependent preventive effect of AS-IV on hepatic steatosis.

CONCLUSION

These results show that the changes in intestinal flora and BAs serve an essential role in the remission of hepatic steatosis by AS-IV, thereby suggesting that AS-IV may be used as a prebiotic agent to provide viable treatment for NAFLD.

Protective Effects of Protopanaxatriol Saponins on Ulcerative Colitis in Mouse Based on UPLC-Q/TOF-MS Serum and Colon Metabolomics

Ulcerative colitis (UC) is a chronic, nonspecific inflammation of the bowel that mainly affects the mucosa and submucosa of the rectum and colon. Ginsenosides are the main active ingredients in ginseng and show many therapeutic effects in anti-inflammatory diseases, cancer, and nervous system regulation. Protopanaxatriol saponin (PTS) is an important part of saponins, and there is no research on its pharmacological effects on colitis. In this study, a model of ulcerative colitis in mice was induced by having mice freely drink 3.5% dextran sodium sulfate (DSS) solution, and UPLC-Q-TOF-MS-based metabolomics methods were applied to explore the therapeutic effect and protective mechanism of PTS for treating UC. The results showed that PTS could significantly prevent colon shortening and pathological damage and alleviate abnormal changes in UC mouse physiological and biochemical parameters. Moreover, PTS intervention regulated proinflammatory cytokines such as TNF-α, IL-6, and IL-1 in serum, and MPO and NO in colon. Interestingly, PTS could significantly inhibit UC mouse metabolic dysfunction by reversing abnormal changes in 29 metabolites and regulating eleven metabolic pathways. PTS has potential application in the treatment of UC and could alleviate UC in mice by affecting riboflavin metabolism, arachidonic acid metabolism, glycerophospholipid metabolism, retinol metabolism, and steroid hormone biosynthesis and by regulating pentose and glucuronate conversion, linoleic acid metabolism, phenylalanine metabolism, ether lipid metabolism, sphingolipid metabolism, and tyrosine metabolism, which points at a direction for further research and for the development of PTS as a novel natural agent.

Molecular Analysis of the Melanogenesis Inhibitory Effect of Saponins-Rich Fraction of Argania spinosa Leaves Extract

Plant saponins are abundant and diverse natural products with a great potential for use in drug-discovery research. Here, we evaluated extracts of saponins-rich fractions of argan leaves and argan oil extraction byproducts (shell, pulp, press cake) for their effect on melanogenesis. Results show that from among the samples tested, only the saponins-rich fraction from leaves (ALS) inhibited melanin production in B16 murine melanoma (B16) cells. The mechanism of the melanogenesis inhibition was elucidated by determining the protein and mRNA expression of melanogenesis-associated enzymes tyrosinase (TYR), tyrosinase-related protein 1 (TRP1), and dopachrome tautomerase (DCT), and microphthalmia-associated transcription factor (MITF), and performing DNA microarray analysis. Results showed that 10 µg/mL ALS significantly inhibited melanogenesis in B16 cells and human epidermal melanocytes by 59% and 48%, respectively, without cytotoxicity. The effect of ALS on melanogenesis can be attributed to the decrease in TYR, TRP1, and MITF expression at the protein and mRNA levels. MITF inhibition naturally led to the downregulation of the expression of Tyr and Trp1 genes. Results of the DNA microarray analysis revealed the effect on melanogenesis-associated cAMP and Wnt signaling pathways' genes. The results of this study suggest that ALS may be used in cosmeceuticals preparations for hyperpigmentation treatment.

A saponin from astragalus promotes pancreatic ductal organoids differentiation into insulin-producing cells

BACKGROUND

Islet transplantation is an effective treatment for the type 1 and severe type 2 diabetes, but it is restricted by the severe lack of pancreas donors. In vitro differentiation of pancreatic progenitors into insulin-secreting cells is one of the hopeful strategies in the cell transplantation therapy of diabetes. Isoastragaloside I is one of the saponin molecules found in Astragalus membranaceus, which has been demonstrated to alleviate insulin resistance and glucose intolerance in obese mice.

STUDY DESIGN

We established mouse pancreatic ductal organoids (mPDOs) with progenitor characteristics and an insulin promoter-driven EGFP reporter system to screen astragalus saponin components for monomers that can promote insulin-producing cell differentiation.

METHODS

mPDOs treated with or without astragalus saponin monomers were investigated by the insulin promoter-driven EGFP reporter, quantitative PCR, immunofluorescence and flow cytometry to evaluate the expression of endocrine progenitor and β-cell markers.

RESULTS

Isoastragaloside I significantly promoted the expression of β-cell differentiation genes, which was demonstrated by the activation of the insulin promoter-driven EGFP reporter, as well as the significant increase of mRNA levels of the endocrine progenitor marker Ngn3 and the β-cell markers insulin1 and insulin2. Immunostaining studies indicated that the β-cell-specific C-peptide was upregulated in isoastragaloside I-treated mPDOs. FACS analysis revealed that the ratio of C-peptide-secreting cells in isoastragaloside I-treated mPDOs was over 40%. Glucose tolerance tests demonstrated that the differentiated mPDOs could secrete C-peptide in response to glucose stimulation.

CONCLUSIONS

We discover a novel strategy of inducing pancreatic ductal progenitors to differentiate into insulin-producing cells using isoastragaloside I. This approach can be potentially applied to β-cell transplantation in diabetes therapies.

Switchgrass Metabolomics Reveals Striking Genotypic and Developmental Differences in Specialized Metabolic Phenotypes

Switchgrass (Panicum virgatum L.) is a bioenergy crop that grows productively on lands not suitable for food production and is an excellent target for low-pesticide input biomass production. We hypothesize that resistance to insect pests and microbial pathogens is influenced by low-molecular-weight compounds known as specialized metabolites. We employed untargeted liquid chromatography-mass spectrometry, quantitative gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance spectroscopy to identify differences in switchgrass ecotype metabolomes. This analysis revealed striking differences between upland and lowland switchgrass metabolomes as well as distinct developmental profiles. Terpenoid- and polyphenol-derived specialized metabolites were identified, including steroidal saponins, di- and sesqui-terpenoids, and flavonoids. The saponins are particularly abundant in switchgrass extracts and have diverse aglycone cores and sugar moieties. We report seven structurally distinct steroidal saponin classes with unique steroidal cores and glycosylated at one or two positions. Quantitative GC-MS revealed differences in total saponin concentrations in the leaf blade, leaf sheath, stem, rhizome, and root (2.3 ± 0.10, 0.5 ± 0.01, 2.5 ± 0.5, 3.0 ± 0.7, and 0.3 ± 0.01 μg/mg of dw, respectively). The quantitative data also demonstrated that saponin concentrations are higher in roots of lowland (ranging from 3.0 to 6.6 μg/mg of dw) than in upland (from 0.9 to 1.9 μg/mg of dw) ecotype plants, suggesting ecotypic-specific biosynthesis and/or biological functions. These results enable future testing of these specialized metabolites on biotic and abiotic stress tolerance and can provide information on the development of low-input bioenergy crops.

Switchgrass Metabolomics Reveals Striking Genotypic and Developmental Differences in Specialized Metabolic Phenotypes

Switchgrass (Panicum virgatum L.) is a bioenergy crop that grows productively on lands not suitable for food production and is an excellent target for low-pesticide input biomass production. We hypothesize that resistance to insect pests and microbial pathogens is influenced by low-molecular-weight compounds known as specialized metabolites. We employed untargeted liquid chromatography-mass spectrometry, quantitative gas chromatography-mass spectrometry (GC-MS), and nuclear magnetic resonance spectroscopy to identify differences in switchgrass ecotype metabolomes. This analysis revealed striking differences between upland and lowland switchgrass metabolomes as well as distinct developmental profiles. Terpenoid- and polyphenol-derived specialized metabolites were identified, including steroidal saponins, di- and sesqui-terpenoids, and flavonoids. The saponins are particularly abundant in switchgrass extracts and have diverse aglycone cores and sugar moieties. We report seven structurally distinct steroidal saponin classes with unique steroidal cores and glycosylated at one or two positions. Quantitative GC-MS revealed differences in total saponin concentrations in the leaf blade, leaf sheath, stem, rhizome, and root (2.3 ± 0.10, 0.5 ± 0.01, 2.5 ± 0.5, 3.0 ± 0.7, and 0.3 ± 0.01 μg/mg of dw, respectively). The quantitative data also demonstrated that saponin concentrations are higher in roots of lowland (ranging from 3.0 to 6.6 μg/mg of dw) than in upland (from 0.9 to 1.9 μg/mg of dw) ecotype plants, suggesting ecotypic-specific biosynthesis and/or biological functions. These results enable future testing of these specialized metabolites on biotic and abiotic stress tolerance and can provide information on the development of low-input bioenergy crops.

Quinoa Reduces High-Fat Diet-Induced Obesity in Mice via Potential Microbiota-Gut-Brain-Liver Interaction Mechanisms

The gut microbiota is important in the occurrence and development of obesity. It can not only via its metabolites, but also through microbiota-gut-brain-liver interactions, directly or indirectly, influence obesity. Quinoa, known as one kind of pseudocereals and weight loss food supplements, has been high-profile for its high nutritional value and broad applications. In this context, we produced high-fat diet-induced (HFD) obese mouse models and assessed the efficacy of quinoa with saponin and quinoa without saponin on obesity. We explored the potential therapeutic mechanisms of quinoa using methods such as 16S rRNA, Western blotting, Immunohistochemical (IHC). Our results indicated that quinoa can improve the obese symptoms significantly on HFD mice, as well as aberrant glucose and lipid metabolism. Further analyses suggest that quinoa can regulate microbiota in the colon and have predominantly regulation on Bacteroidetes, Actinobacteria and Desulfovibrio, meanwhile can decrease the F/B ratio and the abundance of Blautia. Contemporaneously, quinoa can upregulate the expression of TGR5 in the colon and brain, as well as GLP-1 in the colon, liver and brain. while downregulate the expression of TLR4 in the colon and liver, as well as markers of ER stress and oxidative stress in livers and serums. Beyond this, tight junctional proteins in colons and brains are also increased in response to quinoa. Therefore, quinoa can effectively reduce obesity and may possibly exert through microbiota-gut-brain-liver interaction mechanisms. IMPORTANCE Gut microbiota has been investigated extensively, as a driver of obesity as well as a therapeutic target. Studies of its mechanisms are predominantly microbiota-gut-brain axis or microbiota-gut-liver axis. Recent studies have shown that there is an important correlation between the gut-brain-liver axis and the energy balance of the body. Our research focus on microbiota-gut-brain-liver axis, as well as influences of quinoa in intestinal microbiota. We extend this study to the interaction between microbiota and brains, and the result shows obvious differences in the composition of the microbiome between the HFD group and others. These observations infer that besides the neurotransmitter and related receptors, microbiota itself may be a mediator for regulating bidirectional communication, along the gut-brain-liver axis. Taken together, these results also provide strong evidence for widening the domain of applicability of quinoa.

Whole-Genome Identification and Analysis of Multiple Gene Families Reveal Candidate Genes for Theasaponin Biosynthesis in Camellia oleifera

Camellia oleifera is an economically important oilseed tree. Seed meals of C. oleifera have a long history of use as biocontrol agents in shrimp farming and as cleaning agents in peoples’ daily lives due to the presence of theasaponins, the triterpene saponins from the genus Camellia. To characterize the biosynthetic pathway of theasaponins in C. oleifera, members of gene families involved in triterpenoid biosynthetic pathways were identified and subjected to phylogenetic analysis with corresponding members in Arabidopsis thaliana, Camellia sinensis, Actinidia chinensis, Panax ginseng, and Medicago truncatula. In total, 143 triterpenoid backbone biosynthetic genes, 1169 CYP450s, and 1019 UGTs were identified in C. oleifera. The expression profiles of triterpenoid backbone biosynthetic genes were analyzed in different tissue and seed developmental stages of C. oleifera. The results suggested that MVA is the main pathway for triterpenoid backbone biosynthesis. Moreover, the candidate genes for theasaponin biosynthesis were identified by WGCNA and qRT-PCR analysis; these included 11 CYP450s, 14 UGTs, and eight transcription factors. Our results provide valuable information for further research investigating the biosynthetic and regulatory network of theasaponins.

Anti-inflammatory, anti-angiogenetic and antiviral activities of dammarane-type triterpenoid saponins from the roots of Panax notoginseng

Panax notoginseng has been used both as a traditional medicine and as a functional food for hundreds of years in Asia. However, the active constituents from P. notoginseng and their pharmacologic properties still need to be further explored. In this study, one new dammarane-type triterpenoid saponin (1), along with fourteen known analogs (2-15) were isolated and identified from the roots of P. notoginseng. The anti-inflammatory, anti-angiogenetic and anti-dengue virus effects of these isolated compounds were further evaluated. Compounds 1, 3, 5-7 and 10-12 exerted anti-inflammatory effects in two different zebrafish inflammatory models. Among them, 11, with the most significant activities, alleviated the inflammatory response by blocking the MyD88/NF-κB and STAT3 pathways. Moreover, compound 15 showed anti-angiogenetic activities in Tg(fli1:EGFP) and Tg(flk1:GFP) zebrafish, while 3 and 5 only inhibited angiogenesis in Tg(fli1:EGFP) zebrafish. Additionally, compounds 1, 3, 6, 8, 9 and 12 suppressed the replication of dengue virus either at the viral adsorption and entry stages or at the intracellular replication step. In conclusion, these findings enrich knowledge of the diversity of saponins in P. notoginseng and suggest that the dammarane-type triterpenoid saponins from P. notoginseng may be developed as potential functional foods to treat inflammation, angiogenesis or dengue-related diseases.

Caspase-1-Dependent Pyroptosis Mediates Adjuvant Activity of Platycodin D as an Adjuvant for Intramuscular Vaccines

Platycodin D (PD) is a potent adjuvant with dual Th1 and Th2 potentiating activity, but its mechanisms of action remain unclear. Here, the C2C12 myoblast cell line and mice were used as in vitro and in vivo models to identify potential signaling pathways involved in the adjuvant activity of PD. PD induced a transient cytotoxicity and inflammatory response in the C2C12 cells and in mouse quadricep muscles. A comparative analysis of microarray data revealed that PD induced similar gene expression profiles in the C2C12 cells and in the quadricep muscles, and triggered rapid regulation of death, immune, and inflammation-related genes, both in vivo and in vitro. It was further demonstrated that caspase-1-dependent pyroptosis was involved in the PD-induced cytotoxicity and inflammatory response in the C2C12 cells via the Ca²⁺–c-jun N-terminal kinase (JNK)/p38 mitogen-activated protein kinase (MAPK)–NLR family pyrin domain containing 3 (NLRP3) inflammasome signaling pathway. Consistently, the in vivo analysis revealed that a local blockage of NLRP3 and caspase-1 inhibited PD-induced cytokine production and immune cell recruitment at the injection site, and impaired the adjuvant activity of PD on antigen-specific immune responses to model antigen ovalbumin (OVA) in mice. These findings identified the caspase-1-dependent adjuvanticity of PD and expanded the current knowledge on the mechanisms of action of saponin-based adjuvants.

Saikosaponin-d alleviates hepatic fibrosis through regulating GPER1/autophagy signaling

BACKGROUND

Hepatic fibrosis is the final pathway of chronic liver disease characterized by excessive accumulation of extracellular matrix (ECM), which eventually develop into cirrhosis and liver cancer. Emerging studies demonstrated that Saikosaponin-d (SSd) exhibits a protective role in liver fibrosis. However, the mechanism underlying anti-liver fibrosis of SSd in vivo and in vitro remains unclear.

METHODS AND RESULTS

Transforming growth factor (TGF)-β and carbon tetrachloride (CCl₄) were used for creating liver fibrosis model in vitro and in vivo, respectively. The role of SSd in regulating liver fibrosis was assessed through Sirius red and Masson staining, and IHC assay. We found that SSd attenuated remarkably CCl₄-induced liver fibrosis as evidenced by decreased collagen level, and decreased expression of fibrotic markers Col 1 and α-SMA. Meanwhile, SSd repressed autophagy activation as suggested by decreased BECN1 expression and increased p62 expression. Compared with HSCs from CCl₄-treated group, the primary HSCs from SSd-treated mice exhibited a marked inactivation of autophagy. Mechanistically, SSd treatment enhanced the expression of GPER1 in primary HSCs and in TGF-β-treated LX-2 cells. GPER1 agonist G1 repressed autophagy activation, whereas GPER1 antagonist G15 activated autophagy and G15 also damaged the function of SSd on suppressing autophagy, leading to subsequent increased levels of fibrotic marker level in LX-2 cells.

CONCLUSIONS

Our findings highlight that SSd alleviates hepatic fibrosis by regulating GPER1/autophagy pathway.