Unraveling potential neuroprotective mechanisms of herbal medicine for Alzheimer's diseases through comprehensive molecular docking analyses

Alzheimer's disease (AD) continues to be a worldwide health concern, demanding innovative therapeutic approaches. This study investigates the neuroprotective potential of herbal compounds by scrutinizing their interactions with Beta-Secretase-1 (BACE1). Through comprehensive molecular docking analyses, three compounds, Masticadienonic acid (ΔG: -9.6 kcal/mol), Hederagenin (ΔG: -9.3 kcal/mol), and Anthocyanins (ΔG: -8.1 kcal/mol), emerge as promising BACE1 ligands, displaying low binding energies and strong affinities. ADME parameter predictions, drug-likeness assessments, and toxicity analyses reveal favorable pharmacokinetic profiles for these compounds. Notably, Masticadienonic Acid exhibits optimal drug-likeness (-3.3736) and negligible toxicity concerns. Hederagenin (drug-likeness: -5.3272) and Anthocyanins (drug-likeness: -6.2041) also demonstrate promising safety profiles. Furthermore, pharmacophore modeling elucidates the compounds' unique interaction landscapes within BACE1's active site. Masticadienonic acid showcases seven hydrophobic interactions and a hydrogen bond acceptor interaction with Thr232. Hederagenin exhibits a specific hydrogen bond acceptor interaction with Trp76, emphasizing its selective binding. Anthocyanins reveal a multifaceted engagement, combining hydrophobic contacts and hydrogen bond interactions with key residues. In conclusion, Masticadienonic acid, Hederagenin, and Anthocyanins stand out as promising candidates for further experimental validation, presenting a synergistic balance of efficacy and safety in combating AD through BACE1 inhibition.

Hederagenin protects against myocardial ischemia-reperfusion injury via attenuating ALOX5-mediated ferroptosis

Hederagenin (HDG), a medical herb, is known for its beneficial activities against diverse diseases. The cardioprotective effect of HDG has been preliminarily disclosed, but the efficacy and underlying mechanism by which HDG protects against myocardial ischemia-reperfusion (MI/R) injury have not been elucidated yet. To simulate MI/R injury, the left anterior descending artery was occluded for 30 min and then reperfusion for 120 min in a rat model, and the cellular model of hypoxia-reoxygenation (H/R) injury was constructed in H9c2 cardiomyocytes. Hematoxylin-eosin, Prussian blue, and 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining were conducted to assess the histological injury, iron deposition, and myocardial infarction. Myocardial enzymes and oxidative stress-related factors were detected using their commercial kits. Lipid peroxidation was measured using BODIPY581/591 probe, and iron content was detected. Cell counting kit (CCK)-8, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), and flow cytometry assays were performed to assess cell viability and apoptosis. Protein levels were investigated by western blot. The interaction between HDG and 5-lipoxygenase (ALOX5) was verified using molecular docking. Our findings indicated that HDG significantly attenuated myocardial dysfunction by reducing infarction and myocardial injury. HDG significantly attenuated myocardial apoptosis in vitro and in vivo, as well as alleviating oxidative stress via reducing reactive oxygen species (ROS) and maintaining the balance between antioxidant and oxidant enzymes. Meanwhile, HDG inhibited I/R-induced ferroptosis in myocardium and cardiomyocytes, including reducing lipid peroxidation and iron level. Moreover, the binding relationship between HDG and ALOX5 was verified, and HDG could concentration dependently downregulate ALOX5. Furthermore, ALOX5 overexpression eliminated the inhibition of HDG on H/R-induced apoptosis, oxidative stress, and ferroptosis in H9c2 cardiomyocytes. HDG ameliorated myocardial dysfunction and cardiomyocyte injury by reducing apoptosis, oxidative stress, and ferroptosis through inhibiting ALOX5, providing a new perspective on the prevention and treatment of MI/R injury.

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.

Hederagenin suppresses ovarian cancer via targeting mitochondrial fission through dynamin-related protein 1

A triterpenoid isolated from the plant Hedera helix, hederagenin was discovered to have anti-cancer, anti-inflammatory, anti-depressant and anti-fibrosis properties both in vivo and in vitro. In this study, the relationship between mitochondrial fission and hederagenin-induced apoptosis in ovarian cancer (OC) was investigated and the underlying mechanisms were deciphered. Hederagenin's cytotoxicity on OC cells was analyzed using colony formation and CCK-8 assays. The effect of hederagenin on OC cells was also verified by a mouse xenograft tumor model. Flow cytometric analysis was conducted to examine hederagenin's effects on mitochondrial membrane potential, apoptosis, and cell cycle OC cells. MitoTracker Red (CMXRos) staining was performed to observe the mitochondrial morphology. The protein levels of Bak, Bcl-2, Caspase 3, Caspase 9, Cyclin D1 and Bax were measured by Western blot. This study found that hederagenin could suppress the in vivo and in vitro SKOV3 and A2780 cell proliferation in an effective manner. Besides, hederagenin altered the mitochondrial membrane potential, induced S-phase and G0/G1-phase arrest, mitochondrial morphology changes, and apoptosis in OC cells. Additionally, our findings further demonstrated that hederagenin changed the mitochondrial morphology by suppressing dynamin-related protein 1 (Drp1), a crucial mitochondrial division factor. Moreover, Drp1 overexpression could reverse hederagenin-induced apoptosis, whereas the Drp1 knockdown had the opposite effect. Furthermore, hederagenin may trigger BAX mitochondrial translocation and apoptosis in OC cells. These results provided a novel perspective on the relationship between the modulation of mitochondrial morphology and the suppression of ovarian cancer by hederagenin.

Molecular Mechanism Analysis of the Effect of Hederagenin Combined with L-OHP on Chemosensitivity of AGS/L-OHP Based on Network Pharmacology

AIMS AND OBJECTIVES

This study aimed to evaluate the pharmacological mechanism of Hederagenin (HD) combined with oxaliplatin (L-OHP) in treating gastric cancer (GC) through network pharmacology combined with experimental verification.

MATERIAL AND METHODS

Network pharmacology methods were used to screen potential targets for HD, L-OHP, and GC-related targets from public databases, and the intersection of the three gene sets was taken. Cross genes were analyzed through protein-protein interaction (PPI) networks to predict core targets, and related pathways were predicted through GO and KEGG enrichment analysis. The experimental results were verified by the in vitro experiments. HD was applied on AGS/L-OHP cells, and then cellular chemosensitivity and the expressions of P-gp, Survivin, Bcl-2, p-Akt, and p-PI3K genes were detected. Wound assay and Transwell Chamber assay were employed to detect the effect of HD on AGS/L-OHP cells. Nude mice xenograft models transfected using AGS/L-OHP cells were also treated with HD in order to verify the results. The size and weight of the tumor, as well as the expressions of P-gp, Survivin, Bcl-2, p- Akt and p-PI3K genes, were also measured.

RESULTS

KEGG analysis showed that the anti-gastric cancer effect of HD was mediated mainly by PI3K-Akt signaling pathways. The PI3K-Akt signaling pathway containing more enriched genes may play a greater role in anti-gastric cancer. It was observed that for AGS/L-OHP cells jointly treated with HD and L-OHP, their activity, migration and invasion were significantly lower than those treated only using HD or L-OHP group. Moreover, expressions of p-Akt, p- PI3K, Bcl-2, P-gp, and Survivin for the HD+L-OHP group decreased significantly. Results of the in vivo experiments showed that the sizes and weights of tumors in the HD+L-OHP group were the lowest compared to the HD group and L-OHP group.

CONCLUSION

Our findings suggest that HD may reduce the resistance of AGS/L-OHP cells to LOHP by regulating the PI3K/Akt signaling pathway.

Hederagenin Upregulates PTPN1 Expression in Aβ-Stimulated Neuronal Cells, Exerting Anti-Oxidative Stress and Anti-Apoptotic Activities

Alzheimer's disease (AD) is a prevalently neurodegenerative disease characterized by neuronal damage which is associated with amyloid-β (Aβ) accumulation. Hederagenin is a triterpenoid saponin, exerting anti-apoptotic, anti-oxidative, anti-inflammatory, anti-tumoral, and neuroprotective activities. However, its role in AD progression is still obscure. The aim of this study was to explore the influences of hederagenin on Aβ-caused neuronal injury in vitro. Neuronal cells were treated with Aβ25-35 (Aβ) to establish a cellular model of AD. Cell viability was assessed using cell counting kit-8 (CCK-8). Oxidative stress was evaluated by detecting reactive oxygen species (ROS) generation and superoxide dismutase (SOD) activity. Apoptosis was investigated using TUNEL staining and caspase-3 activity assays. Protein tyrosine phosphatase nonreceptor type 1 (PTPN1) was screened by bioinformatics analysis. Protein levels of PTPN1 and protein kinase B (Akt) were measured by western blotting. Hederagenin (2.5, 5, and 10 μM) alone did not affect viability of neuronal cells, but relieved Aβ-induced viability reduction. Hederagenin mitigated Aβ-induced increase in ROS accumulation and decrease in SOD activity. Hederagenin attenuated Aβ-induced increase in apoptotic rate and caspase-3 activity. PTPN1 was screened as a target of hederagenin against AD by bioinformatics analysis. Hederagenin treatment resisted Aβ-induced decrease in PTPN1 mRNA and protein levels in neuronal cells. PTPN1 silencing attenuated the suppressive functions of hederagenin in Aβ-stimulated oxidative stress and apoptosis. Hederagenin mitigated Aβ-induced Akt signaling inactivation by upregulating PTPN1 expression. In conclusion, hederagenin attenuates oxidative stress and apoptosis in neuronal cells stimulated with Aβ by promoting PTPN1/Akt signaling activation.

Advances in the anti-tumor potential of hederagenin and its analogs

Hederagenin is a pentacyclic triterpenoid that is widely distributed as the main pharmaceutical ingredient in various medicinal plants. Similarly as other pentacyclic triterpenoids, hederagenin has various pharmacological effects such as anti-tumor, anti-inflammatory, anti-depressant, and anti-viral activities. In particular, the anti-tumor activity of hederagenin indicates its potential for development into highly effective chemotherapeutic agents. Studies revealed that hederagenin effectively suppresses the growth of various tumor cell lines in vitro and interacts with several molecular targets that play essential roles in various cellular signaling pathways. The compound suppresses transformation, inhibits proliferation, and induces apoptosis in tumor cells. In this review, we highlight research progress on the source, pharmacokinetics, pharmacological activity, and mechanism of action of hederagenin and the anti-tumor activity of its analogs by integrating and analyzing relevant domestic and international studies and providing a basis for their further development and application.

Hederagenin Induces Apoptosis of Human Hepatoma HepG2 Cells via the Mitochondrial Pathway

OBJECTIVE

The objective of this study is to assess the antitumor effects of hederagenin (HDG) in liver cancer (LC) cells and explore the related mechanisms.

METHODS AND MATERIALS

HepG2 cells were treated with HDG and cisplatin, respectively. The CCK8 assay was used to detect cell activity, DAPI staining was used to detect the proportion of living cells, TUNEL assay to detect the proportion of apoptotic cells, flow cytometry to detect the membrane potential, fluoroscopic electron microscopy to detect microstructural changes to the mitochondrial, and western blot analysis and high-content screening to detect apoptosisrelated proteins.

RESULTS

Treatment with HDG inhibited the growth of HepG2 cells, decreased the proportion of viable cells, increased the proportion of apoptotic cells, and significantly increased the proportion of cells in the G1 phase. Fluorescence staining showed that HDG damaged the mitochondria of HepG2 cells and significantly decreased the number of mitochondria. Flow cytometry showed that HDG decreased the mitochondrial membrane potential of HepG2 cells. Observations by electron microscopy showed that HDG caused swelling and vacuole formation of the mitochondria of HepG2 cells. HDG significantly reduced the average fluorescence intensity of Bcl-2 in HepG2 cells and significantly increased that of the pro-apoptosis proteins Bax, Cytochrome-c, and Caspase-3.

CONCLUSION

HDG induced apoptosis of HepG2 cells via the mitochondrial pathway.

Proteomics identifies differentially expressed proteins in glioblastoma U87 cells treated with hederagenin

OBJECTIVE

We investigated differentially expressed proteins (DEPs) in human glioblastoma U87 cells after treatment with hederagenin as a therapeutic screening mechanism and provided a theoretical basis for hederagenin in treating glioblastoma.

METHODS

The Cell Counting Kit 8 assay was used to analyze the inhibitory effect of hederagenin on the proliferation of U87 cells. Protein was identified by tandem mass tags and LC-MS/MS analysis techniques. Annotation of DEPs, Gene Ontology enrichment and function, and Kyoto Encyclopedia of Genes and Genomes pathways and domains were all examined by bioinformatics. According to the TMT results, hub protein was selected from DEPs for WB verification.

RESULTS

Protein quantitative analysis found 6522 proteins in total. Compared with the control group, 43 DEPs (P < 0.05) were involved in the highly enriched signaling pathway in the hederagenin group, among which 20 proteins were upregulated, and 23 proteins were downregulated. These different proteins are mainly involved in the longness regulating pathway-WORM, the hedgehog signaling pathway, Staphylococcus aureus infection, complement, coagulation cascades, and mineral absorption. KIF7 and ATAD2B expression were significantly down-regulated and PHEX and TIMM9 expression were significantly upregulated, according to WB analysis, supporting the TMT findings.

CONCLUSION

Hederagenin inhibition of GBM U87 cells may be related to KIF7, which is mainly involved in the hedgehog signaling pathway. Our findings lay a foundation for additional study of the therapeutic mechanism of hederagenin.

Hederagenin ameliorates renal fibrosis in chronic kidney disease through blocking ISG15 regulated JAK/STAT signaling

Interstitial fibrosis is the key pathological characteristics of chronic kidney diseases (CKD). In this study, we reported that hederagenin (HDG) can effectively improve the renal interstitial fibrosis and its mechanism. We constructed CKD animal models of ischemia reperfusion injury (IRI) and unilateral ureteral obstruction (UUO) respectively to observe the improvement effect of HDG on CKD. The results showed that HDG can effectively improve the pathological structure of kidney and the renal fibrosis in CKD mice. Meanwhile, HDG can also significantly reduce the expression of α-SMA and FN induced by TGF-β in Transformed C3H Mouse Kidney-1 (TCMK1) cells. Mechanistically, we performed transcriptome sequencing on UUO kidneys treated with HDG. By real time PCR screening of the sequencing results, we determined that ISG15 plays an important role in the intervention of HDG in CKD. Subsequently, we knocked-down ISG15 in TCMK1 and found that ISG15 knock-down significantly inhibited TGF-β-induced fibrotic protein expression and JAK/STAT activation. Finally, we performed electrotransfection and used liposomes to transfect ISG15 overexpression plasmids to up-regulate ISG15 in kidney and cells, respectively. We found that ISG15 can aggravate renal tubular cell fibrosis and abolish the protection of HDG on CKD. These results indicated that HDG significantly improves renal fibrosis in CKD by inhibiting ISG15 and its downstream JAK/STAT signaling pathway, which provides a new drug and research target for the subsequent treatment of CKD.

Hederagenin improves Alzheimer's disease through PPARα/TFEB-mediated autophagy

BACKGROUND

Autophagic flux is coordinated by a network of master regulatory genes, which centered on transcription factor EB (TFEB). The disorders of autophagic flux are closely associated with Alzheimer's disease (AD), and thus restoring autophagic flux to degrade pathogenic proteins has become a hot therapeutic strategy. Hederagenin (HD), a triterpene compound, isolated from a variety food such as Matoa (Pometia pinnata) Fruit, Medicago sativa, Medicago polymorpha L. Previous studies have shown that HD has the neuroprotective effect. However, the effect of HD on AD and underlying mechanisms are unclear.

PURPOSE

To determine the effect of HD on AD and whether it promotes autophagy to reduce AD symptoms.

STUDY DESIGN

BV2 cells, C. elegans and APP/PS1 transgenic mice were used to explore the alleviative effect of HD on AD and the molecular mechanism in vivo and in vitro.

METHODS

The APP/PS1 transgenic mice at 10 months were randomized into 5 groups (n = 10 in each group) and orally administrated with either vehicle (0.5% CMCNa), WY14643 (10 mg/kg/d), low-dose of HD (25 mg/kg/d), high-dose of HD (50 mg/kg/d) or MK-886 (10 mg/kg/d) + HD (50 mg/kg/d) for consecutive 2 months. The behavioral experiments including morris water maze test, object recognition test and Y maze test were performed. The effects of HD on Aβ deposition and alleviates Aβ pathology in transgenic C. elegans were operated using paralysis assay and fluorescence staining assay. The roles of HD in promoting PPARα/TFEB-dependent autophagy were investigated using the BV2 cells via western blot analysis, real-time quantitative PCR (RT-qPCR), molecular docking, molecular dynamic (MD) simulation, electron microscope assay and immunofluorescence.

RESULTS

In this study, we found that HD upregulated mRNA and protein level of TFEB and increased the distribution of TFEB in the nucleus, and the expressions of its target genes. HD also promoted the expressions of LC3BII/LC3BI, LAMP2, etc., and promoted autophagy and the degradation of Aβ. HD reduced Aβ deposition in the head area of C. elegans and Aβ-induced paralysis. HD improved cognitive impairment and pathological changes in APP/PS1 mice by promoting autophagy and activating TFEB. And our results also showed that HD could strongly target PPARα. More importantly, these effects were reversed by treatment of MK-886, a selective PPARα antagonist.

CONCLUSION

Our present findings demonstrated that HD attenuated the pathology of AD through inducing autophagy and the underlying mechanism associated with PPARα/TFEB pathway.

Hederagenin ameliorates cisplatin-induced acute kidney injury via inhibiting long non-coding RNA A330074k22Rik/Axin2/β-catenin signalling pathway

BACKGROUND

Acute kidney injury (AKI), a kidney disease with high morbidity and mortality, is characterized by a dramatic decline in renal function. Hederagenin (HDG), a pentacyclic triterpenoid saponin isolated from astragalus membranaceus, has been shown to have significant anti-inflammatory effects on various diseases. However, the effects of HDG on renal injury and inflammation in AKI has not been elucidated.

METHODS

In this research, mice model of AKI was established by intraperitoneal injection of cisplatin in vivo, the inflammatory model of renal tubular epithelial cells was established by LPS stimulation in vitro, and HDG was used to intervene in vitro and in vivo models. Transcriptome sequencing was used to analyze the alterations of LncRNA and mRNA expression in AKI model and LncRNA-A330074k22Rik (A33) knockdown cells, respectively. Renal in situ electrotransfer knockdown plasmid was used to establish mice model of AKI with low expression of A33 in kidney.

RESULTS

The results showed that HDG effectively alleviate cisplatin-induced kidney injury and inflammation in mice. Transcriptome sequencing results showed that multiple LncRNAs in kidney of AKI model exhibited significant changes, among which LncRNA-A33 had the most obvious change trend. Subsequent results showed that A33 was highly expressed in kidney of AKI mice and LPS-induced renal tubular cells. After in situ renal electroporation knockdown plasmid down-regulated A33 in kidney of AKI mice, it was found that inhibition of A33 could significantly relieve cisplatin-induced kidney injury and inflammation of AKI, while HDG could effectively suppress the expression of A33 in vitro and in vivo, respectively. Subsequently, transcriptome sequencing was again used to analyze the changes in mRNA expression of renal tubular cells after A33 knockdown by siRNA. The results showed that a large number of inflammation-related signaling pathways were down-regulated, Axin2 and its downstream β-catenin signal were significantly inhibited. Cell recovery test showed that HDG inhibited Axin2/β-catenin signal by down-regulating A33, and improved kidney injury and inflammation of AKI.

CONCLUSION

Taken together, HDG significantly ameliorated cisplatin-induced kidney injury through LncRNA-A330074k22Rik/Axin2/β-catenin signal axis, which providing a potential therapeutic approach for the treatment of AKI.

The protective effect of hederagenin on renal fibrosis by targeting muscarinic acetylcholine receptor

Hederagenin (HE) plays a protective role by inhibiting cell proliferation and ameliorating fibrosis. The current therapy for Chronic kidney disease (CKD) often result in the risks of side effects. The present study aimed to explore whether it can protect against renal fibrosis and unveil the underlying mechanism. Transforming growth factor (TGF)-β was used to induce the fibroblasts NRK-49 F for the simulation of renal fibrosis. The cell viability and expression of fibrosis-related proteins in TGF-β-treated NRK-49 F cells was, respectively, measured by Cell Counting Kit-8 (CCK-8) and western blot. After predicting the target genes of HE, M3 receptor was measured in NRK-49 F cells treated with TGF-β alone or in combination with HE. Then, M3 receptor was silenced in TGF-β-treated NRK-49 F cells for the detection of its role in proliferation and fibrosis. Muscarinic acetylcholine receptor M3 (M3 receptor) agonist pilocarpine was further added to determine the role of M3 receptor involved. HE inhibited the proliferation and fibrosis of TGF-β-treated NRK-49 F cells. M3 receptor was predicted to be a target of HE. Moreover, interference of M3 receptor improved the proliferation and fibrosis of TGF-β-treated NRK-49 F cells. Further addition of pilocarpine reversed the inhibitory effect of HE on proliferation and fibrosis of TGF-β-treated NRK-49 F cells. HE protects against renal fibrosis in NRK-49 F cells by targeting Muscarinic acetylcholine receptor, which will provide theoretical basis for the clinical use of HE for kidney-related disease treatment.

Suppression of NOD-like receptor protein 3 inflammasome activation and macrophage M1 polarization by hederagenin contributes to attenuation of sepsis-induced acute lung injury in rats

Acute lung injury (ALI) is a major leading cause of death in sepsis patients. Hederagenin (HG), derived from Hedera helix Linné, has anti-inflammatory effects, while its role in sepsis-induced ALI has not been elucidated. In vivo, rats were subjected to cecal ligation and puncture to induce ALI and then treated with HG (12.5, 25, or 50 mg/kg) by gavage. Administration of HG raised survival rate, ameliorated lung injury, and decreased lung wet/dry ratio and inflammatory cell accumulation in bronchoalveloar lavage fluid (BALF) of ALI rats. HG inhibited macrophage polarization toward the M1 phenotype as evidenced by decreased CD86 expression in rat lung tissues. Moreover, HG decreased the secretion of TNF-α, IL-6 and monocyte chemoattractant protein-1 (MCP-1) in BALF and the levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lung tissues. In vitro, phorbol-12-myristate-13-acetate (PMA)-differentiated THP-1 macrophages were stimulated with 100 ng/mL lipopolysaccharide. HG treatment inhibited M1 macrophage polarization and the production of M1-related pro-inflammatory mediators (IL-6, MCP-1, iNOS, and COX-2). Mechanistically, HG inhibited NLRP3 inflammasome activation and subsequent release of IL-18 and IL-1β, and suppressed NF-κB signaling pathway both in vivo and in vitro. Notably, HG treatment further emphasized the inhibitory effect of NF-κB inhibitor BAY11-7082 on NLRP3 inflammasome activation and macrophage M1 polarization. Taken together, HG exerts a protective effect against sepsis-induced ALI by reducing the inflammatory response and macrophage M1 polarization, which may involve NF-κB pathway-modulated NLRP3 inflammasome activation.

Immunomodulatory and anti-inflammatory efficacy of hederagenin-coated maghemite (γ-Fe2O3) nanoparticles in an atopic dermatitis model

We investigated the immunomodulatory and anti-inflammatory efficacy of hederagenin coating on maghemite (γ-Fe₂O₃) nanoparticles (HM) in atopic dermatitis (AD), as well as the physical and optical properties of maghemite nanoparticles (MP) using SEM, XRD spectroscopy, UV-vis spectra, Raman spectra, and FTIR spectroscopy. Dose-dependent treatment with HM (10, 50, 100, 200 μg/mL) inhibited the expression of Interleukin-2 (IL-2) and Tumor necrosis factor- α (TNF-α) in inflammatory induced HaCaT and Jurkat cells with inflammation caused by TNF/IFN-γ and PMA/A23187. AD model was induced by performing topical application of 2,4-dinitrochlorobenzene (DNCB) and dermatophagoides farinae extract (DFE) for a 31-day period on 8-week-old BALB/c mice. The HM treatments efficiently diminished the AD-like cutaneous lesion induced by DNCB-DFE sensitization in mice. Compared to the AD-only groups, HM treatment considerably attenuated mast cell infiltration and lowered epidermal, and dermal thickness of mice ears skin. In addition, HM treatment prominently alleviated the enlarged size and weight of lymph nodes. Furthermore, HM treatment resulted in a notable reduction in the mRNA expression of Th1 cytokines (TNF-α and IFN-γ), Th2 cytokines (IL-4 and IL-6), Th17 (IL-17), and TSLP. Our data showed that HM provides better AD attenuation compared to MP. Additionally, HM had synergistic effect and act as anti-inflammatory and immunomodulatory agent. Thus, HM shows great potential in AD medication and as a substitution of non-steroid-based medication.

Inhibitory effect of hederagenin on Streptococcus pneumoniae pneumolysin in vitro

Streptococcus pneumoniae is an important pathogen that causes otitis media, pneumonia, meningitis and bacteremia. As an important virulence factors of S. pneumoniae, pneumolysin (PLY) can penetrate cell membranes and lead to cell lysis and inflammation, which is one of the main causes of infection and damage of S. pneumoniae. Therefore, using pneumolysin as a target to study its inhibitors can provide a new treatment strategy for pneumococcal disease. This study analyzed the inhibitory effect of the natural compound hederagenin on PLY in vitro. The results show that hederagenin has great potential as a new strategy for the treatment of pneumococcal diseases.

Design, synthesis, and biological evaluation of hederagenin derivatives with improved aqueous solubility and tumor resistance reversal activity

Multidrug resistance (MDR) has become a major obstacle to malignancies treatment by chemotherapeutic drugs, therefore, it is important to develop MDR reversal agents with high activity. We have previously found that the hederagenin (HD) derivative HBQ showed good tumor MDR reversal activity in vitro and in vivo but had poor solubility. In this study, to enhance the aqueous solubility and tumor MDR reversal activity of HBQ, three series of HD derivatives were designed and synthesized. Nitrogen-containing heterocyclic-substituted, PEGylated, and ring-A substituted derivatives significantly reversed the MDR phenotype of KBV (multidrug-resistant oral epidermoid carcinoma) cells toward paclitaxel at a concentration of 10 μM in MTT assays. The PEGylated derivatives 10c-10e had increased aqueous solubility compared with HBQ by 18-657 fold, while maintaining tumor MDR reversal activity. The most in vitro active compound 10c possessed good chemical stability to an esterase over 24 h and enhanced the sensitivity of KBV cells to paclitaxel and vincristine with IC₅₀ values of 4.58 and 0.79 nM, respectively. Mechanism studies indicated that compound 10c increased the accumulation of P-glycoprotein (P-gp) substrates rhodamine 123 and Flutax1 in KBV cells and MCF-7T (paclitaxel-resistant breast carcinoma) cells, that is to say, compound 10c exerted the reversal effect of tumor MDR by inhibiting the efflux function of P-gp. Finally, the structure-activity relationships were further investigated by analyzing the relationship between structure and tumor MDR reversal activity of HD derivatives. This study highlights the potential of PEGylated HD derivatives such as compound 10c for the development of tumor MDR reversal agents and provides information for the further improvement of the aqueous solubility and tumor MDR reversal activity of HD derivatives in the future.

The protective effect of Hederagenin on pulmonary fibrosis by regulating the Ras/JNK/NFAT4 axis in rats

As a respiratory disease with high morbidity and mortality, pulmonary fibrosis (PF) has been a serious threat to people's health. Hederagenin (HDG) is a pentacyclic triterpenoid saponin widely distributed in various plants. This study explored the role of HDG in Bleomycin (BLM)-induced PF and the molecular mechanism. The results showed that HDG reduced BLM-induced pulmonary dysfunction, pathological damage in a dose-dependent manner. Besides, HDG reduced BLM-induced collagen deposition by decreasing the levels of α-SMA, Collagen I and hydroxproline. Furthermore, HDG reduced the levels of inflammatory cytokines (TNF-α and IL-6), TGF-β1 and connective tissue growth factor (CTGF) in bronchoalveolar lavage fluid (BALF) or serum. Further mechanism analysis indicated that HDG inhibited the expression of Ras and phosphorylation of JNK and NFAT4 in a dose-dependent manner. However, the JNK pathway activator Anisomycin reversed this inhibitory effect. In conclusion, these findings suggest that HDG may be a potential target drug for PF therapy.

Hederagenin protects mice against ovariectomy-induced bone loss by inhibiting RANKL-induced osteoclastogenesis and bone resorption

AIMS

Postmenopausal osteoporosis and other osteolytic bone diseases are often caused by the elevation in osteoclastogenesis and/or increased osteoclastic bone resorption, leading to excessive bone loss. Hederagenin (Hed) is a pentacyclic triterpenoid saponin extracted from various natural medicinal plants and exhibits numerous biological activities and may offer benefits against bone-related conditions. We evaluated the effects of Hed on osteoclast formation and bone resorption in vitro and the in vivo therapeutic benefits in the mouse model of ovariectomy (OVX)-induced bone loss.

MAIN METHODS

In vitro, osteoclast formation were determined by TRAcp staining; bone resorption were examined using Hydroxyapatite resorption assay and Podosomal actin belt formation assay; Related molecular mechanisms were determined by western blot assay. Construction of OVX mice by bilateral oophorectomy to simulate bone loss in vivo.

KEY FINDINGS

In vitro cellular assays showed that Hed inhibited RANKL-induced osteoclast formation and osteoclast bone (hydroxyapatite) resorption as well as marker gene expression from BMM culture. Mechanistically, Hed attenuated RANKL-induced intracellular reactive oxygen species (ROS) production, and MAPK signaling pathway (ERK and p38) activation which curbed the downstream induction of c-Fos and NFATc1. Consistent with the in vitro findings, Hed administration effectively protected OVX mice from bone loss by reducing osteoclast number and activity on bone surface.

SIGNIFICANCE

Our data provided promising evidence for the potential use of Hederagenin in the treatment of osteoclast-mediated osteolytic bone diseases such as postmenopausal osteoporosis.

Hederagenin glycosides from the fruits of Blighia unijugata

A phytochemical investigation of Blighia unijugata led to the isolation of eleven hederagenin glycosides. Among these compounds, six are previously undescribed, two are described in their native forms for the first time and three are known whereas firstly isolated from Blighia unijugata. The structure of the undescribed compounds was elucidated on the basis of 2D NMR and mass spectrometry analyses as 3-O-β-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-3-O-acetyl-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-glucopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-3-O-acetyl-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl ester, 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl ester and 3-O-β-D-xylopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl ester. These results revealed the existence of several conserved structural features that could be used as chemotaxonomic markers for the Blighia genus such as the glycosidic sequence 3-O-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyl, the occurrence of 3-O-acetylated β-D-glucopyranosyl units and the systematic presence of hederagenin as aglycone.

Leishmanicidal and cytotoxic activity of hederagenin-bistriazolyl derivatives

Aiming to obtain new potent leishmanicidal and cytotoxic compounds from natural sources, the triterpene hederagenin was converted into several new 1,2,3-triazolyl derivatives tethered at C-23 and C-28. For this work hederagenin was isolated from fruits of Sapindus saponaria and reacted with propargyl bromide to afford as a major product bis-propargylic derivative 1 in 74%. Submitting this compound to Huisgen 1,3-dipolar cycloaddition reactions with several azides afforded the derivatives 2-19 with yields in the range of 40-87%. All compounds have been screened for in vitro cytotoxic activity in a panel of five human cancer cell lines by a SRB assay. The bioassays showed that compound 19 was the most cytotoxic against all human cancer cell lines with EC₅₀ = 7.4-12.1 μM. Moreover, leishmanicidal activity was evaluated through the in vitro effect in the growth of Leishmania infantum, and derivatives 1, 2, 5 and 17 were highly effective preventing proliferation of intracellular amastigote forms of L. infantum (IC₅₀ = 28.8, 25.9, 5.6 and 7.4 μM, respectively). All these compounds showed a higher selectivity index and low toxicity against two strains of kidney BGM and liver HepG2 cells. Compound 5 has higher selectivity (1780 times) in comparison with the commercial antimony drug and is around 8 times more selective than the most active compound previously reported hederagenin derivative. Such high activity associated with low toxicities make the new bis-traiazolyl derivatives promising candidates for the treatment of leishmaniasis. In addition, hederagenin and some derivatives (2, 5 and 17) showed interaction in the binding site of the enzyme CYP51_Li.

Oleanolic acid and hederagenin glycosides from Weigela stelzneri

Four previously undescribed and one known oleanolic acid glycosides were isolated from the roots of Weigela stelzneri, and one previously undescribed and three known hederagenin glycosides were isolated from the leaves. Their structures were elucidated mainly by 2D NMR spectroscopic analysis and mass spectrometry as 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyloleanolic acid, 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranosyloleanolic acid, 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-glucopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranosyloleanolic acid, 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyloleanolic acid 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glucopyranosyl ester, and 3-O-β-D-glucopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin 28-O-β-D-xylopyranosyl-(1 → 6)-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl ester. The majority of the isolated compounds were evaluated for their cytotoxicity against two tumor cell lines (SW480 and EMT-6), and for their anti-inflammatory activity. The compounds 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosyloleanolic acid and 3-O-β-D-glucopyranosyl-(1 → 2)-[β-D-xylopyranosyl-(1 → 4)]-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-β-D-xylopyranosyloleanolic acid exhibited the strongest cytotoxicity on both cancer cell lines. They revealed a 50% significant inhibitory effect of the IL-1β production by PBMCs stimulated with LPS at a concentration inducing a very low toxicity of 23% and 28%, respectively.

Hederagenin, a major component of Clematis mandshurica Ruprecht root, attenuates inflammatory responses in RAW 264.7 cells and in mice

Clematis mandshurica Ruprecht root has been used in Asia as a traditional anti-inflammatory, analgesic, and antitumor agent. Its main active component is hederagenin, a naturally occurring triterpene, and in this study, we examined the anti-inflammatory effects of hederagenin in lipopolysaccharide-stimulated RAW 264.7 cells using an enzyme-linked immunosorbent assay, Western blot, and RT-PCR. In addition, its effects on acute inflammation in vivo were observed using a carrageenan-induced mouse hind paw edema assay. Furthermore, the changes on the histopathology and histomorphometry of hind paw skins were examined using carrageenan-treated mice. Treatment with hederagenin (10, 30 and 100μM) resulted in inhibited levels of protein expression of lipopolysaccharide-stimulated iNOS, COX-2, and NF-κB as well as production of NO, PGE2, TNF-α, IL-1β, and IL-6 induced by lipopolysaccharide. Consistent with these results, hederagenin also dose-dependently reduced the lipopolysaccharide-induced mRNA levels of iNOS and COX-2, and of the above-mentioned cytokines. Interestingly, results of the carrageenan-induced mouse hind paw edema assay showed an anti-edema effect of hederagenin. Furthermore, hederagenin (30mg/kg) inhibited the carrageenan-induced increases in skin thicknesses, infiltrated inflammatory cells, and mast cell degranulation. These results suggest that hederagenin may possess anti-inflammatory activities.