Exploring the Potential of Oleanolic Acid Dimers-Cytostatic and Antioxidant Activities, Molecular Docking, and ADMETox Profile.

The presented work aimed to explore the potential of oleanolic acid dimers (OADs): their cytostatic and antioxidant activities, molecular docking, pharmacokinetics, and ADMETox profile. The cytostatic properties of oleanolic acid (1) and its 14 synthesised dimers (2a-2n) were evaluated against 10 tumour types and expressed as IC50 values. Molecular docking was performed with the CB-Dock2 server. Antioxidant properties were evaluated with the CUPRAC method. ADMETox properties were evaluated with the ADMETlab Manual (2.0) database. The results indicate that the obtained OADs can be effective cytostatic agents, for which the IC50 not exceeded 10.00 for many tested cancer cell lines. All OADs were much more active against all cell lines than the mother compound (1). All dimers can inhibit the interaction between the 1MP8 protein and cellular proteins with the best results for compounds 2f and 2g with unsaturated bonds within the linker. An additional advantage of the tested OADs was a high level of antioxidant activity, with Trolox equivalent for OADs 2c, 2d, 2g-2j, 2l, and 2m of approximately 0.04 mg/mL, and beneficial pharmacokinetics and ADMETox properties. The differences in the DPPH and CUPRAC assay results obtained for OADs may indicate that these compounds may be effective antioxidants against different radicals.

Biological Properties of Oleanolic Acid Derivatives Bearing Functionalized Side Chains at C-3.

Triterpene acids are a class of pentacyclic natural carboxylic compounds endowed with a variety of biological activities including antitumor, antimicrobial, and hepatoprotective effects. In this work, several oleanolic acid derivatives were synthesized by structurally modifying them on the C-3 position. All synthesized derivatives were evaluated for possible antibacterial and antiviral activity, and among all the epimers, 6 and 7 demonstrated the best biological activities. Zone-of-inhibition analyses were conducted against two strains, E. coli as a Gram-negative and S. aureus as a Gram-positive model. Subsequently, experiments were performed using the microdilution method to determine the minimum inhibitory concentration (MIC). The results showed that only the derivative with reduced hydrogen bonding ability on ring A possesses remarkable activity toward E. coli. The conversion from acid to methyl ester implies a loss of activity, probably due to a reduced affinity with the bacterial membrane. Before the antiviral activity, the cytotoxicity of triterpenes was evaluated through a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Samples 6 and 7 showed less than 50% cytotoxicity at 0.625 and 1 mg/mL, respectively. The antiviral activity against SARS-CoV-2 and PV-1 did not indicate that triterpene acids had any inhibitory capacity in the sub-toxic concentration range.

Principal Bioactive Properties of Oleanolic Acid, Its Derivatives, and Analogues.

Natural products have always played an important role in pharmacotherapy, helping to control pathophysiological processes associated with human disease. Thus, natural products such as oleanolic acid (OA), a pentacyclic triterpene that has demonstrated important activities in several disease models, are in high demand. The relevant properties of this compound have motivated re-searchers to search for new analogues and derivatives using the OA as a scaffold to which new functional groups have been added or modifications have been realized. OA and its derivatives have been shown to be effective in the treatment of inflammatory processes, triggered by chronic diseases or bacterial and viral infections. OA and its derivatives have also been found to be effective in diabetic disorders, a group of common endocrine diseases characterized by hyperglycemia that can affect several organs, including the liver and brain. This group of compounds has been reported to exhibit significant bioactivity against cancer processes in vitro and in vivo. In this review, we summarize the bioactive properties of OA and its derivatives as anti-inflammatory, anti-bacterial, antiviral, anti-diabetic, hepatoprotective, neuroprotective, and anticancer agents.

Oleanolic acid alleviating ischemia-reperfusion injury in rat severe steatotic liver via KEAP1/NRF2/ARE.

Severe steatosis in donor livers is contraindicated for transplantation due to the high risk of ischemia-reperfusion injury (IRI). Although Ho-1 gene-modified bone marrow mesenchymal stem cells (HO-1/BMMSCs) can mitigate IRI, the role of gut microbiota and metabolites in this protection remains unclear. This study aimed to explore how gut microbiota and metabolites contribute to HO-1/BMMSCs-mediated protection against IRI in severe steatotic livers. Using rat models and cellular models (IAR20 and THLE-2 cells) of steatotic liver IRI, this study revealed that ischemia-reperfusion led to significant liver and intestinal damage, heightened immune responses, impaired liver function, and altered gut microbiota and metabolite profiles in rats with severe steatosis, which were partially reversed by HO-1/BMMSCs transplantation. Integrated microbiome and metabolome analyses identified gut microbial metabolite oleanolic acid as a potential protective agent against IRI. Experimental validation showed that oleanolic acid administration alone alleviated IRI and inhibited ferroptosis in both rat and cellular models. Network pharmacology and molecular docking implicated KEAP1/NRF2 pathway as a potential target of oleanolic acid. Indeed, OA experimentally upregulated NRF2 activity, which underlies its inhibition of ferroptosis and protection against IRI. The gut microbial metabolite OA protects against IRI in severe steatotic liver by promoting NRF2 expression and activity, thereby inhibiting ferroptosis.

Oleanolic Acid Dimers with Potential Application in Medicine-Design, Synthesis, Physico-Chemical Characteristics, Cytotoxic and Antioxidant Activity.

The present work aimed to obtain a set of oleanolic acid derivatives with a high level of cytotoxic and antioxidant activities and a low level of toxicity by applying an economical method. Oleanolic acid was alkylated with α,ω-dihalogenoalkane/α,ω-dihalogenoalkene to obtain 14 derivatives of dimer structure. All of the newly obtained compounds were subjected to QSAR computational analysis to evaluate the probability of the occurrence of different types of pharmacological activities depending on the structure of the analysed compound. All dimers were tested for cytotoxicity activity and antioxidant potential. The cytotoxicity was tested on the SKBR-3, SKOV-3, PC-3, and U-87 cancer cell lines with the application of the MTT assay. The HDF cell line was applied to evaluate the tested compounds' Selectivity Index. The antioxidant test was performed with a DPPH assay. Almost all triterpene dimers showed a high level of cytotoxic activity towards selected cancer cell lines, with an IC50 value below 10 µM. The synthesised derivatives of oleanolic acid exhibited varying degrees of antioxidant activity, surpassing that of the natural compound in several instances. Employing the DPPH assay, compounds 2a, 2b, and 2f emerged as promising candidates, demonstrating significantly higher Trolox equivalents and highlighting their potential for pharmaceutical and nutraceutical applications. Joining two oleanolic acid residues through their C-17 carboxyl group using α,ω-dihalogenoalkanes/α,ω-dihalogenoalkenes resulted in the synthesis of highly potent cytotoxic agents with favourable SIs and high levels of antioxidant activity.

Oleanolic acid conjugated chitosan nanocomplex exerts anti-tumor effects by inhibiting autophagy in lung cancer cells through the signal transducers and activators of transcription 3/B cell lymphoma-2 signaling pathway.

The current study reveals the anticancer potential of oleanolic acid conjugated chitosan nanocomplex (OAC) in lung cancer (LC). Cell counting kit-8 (CCK-8) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay were used to detect cell viability, 5-ethynyl-2'-deoxyuridine (EdU) assay to detect cell proliferation, flow cytometry and TUNEL assay to detect cell apoptosis in A549 (ATCC®CCL-185™) and NCIH460 cells. Transwell evaluated cell migration and invasion ability, transmission electron microscopy and immunofluorescence observed autophagy, and Western blotting detected apoptosis- and autophagy-associated proteins. OAC inhibited LC cell viability, migration, and invasion, and induced apoptosis and autophagy depending on the concentration. The phosphorylation of signal transducers and activators of transcription 3 (STAT3) in cells was weakened after OAC treatment. STAT3 activation restored the inhibition of cell viability and induction of apoptosis by OAC. We conclude that OAC induces apoptosis and inhibits cell viability, which may be related to the STAT inactivation. Therefore, OAC is a promising compound for LC therapy.

Advances in the anti-tumor mechanisms of saikosaponin D.

Saikosaponin D, a saponin compound, is extracted from Bupleurum and is a principal active component of the plant. It boasts a variety of pharmacologic effects including anti-inflammatory, antioxidant, immunomodulatory, metabolic, and anti-tumor properties, drawing significant attention in anti-tumor research in recent years. Research indicates that saikosaponin D inhibits the proliferation of numerous tumor cells, curbing the progression of cancers such as liver, pancreatic, lung, glioma, ovarian, thyroid, stomach, and breast cancer. Its anti-tumor mechanisms largely involve inhibiting tumor cell proliferation, promoting tumor cell apoptosis, thwarting tumor-cell invasion, and modulating tumor cell autophagy. Moreover, saikosaponin D enhances the sensitivity to anti-tumor drugs and augments body immunity. Given its multi-faceted anti-tumor roles, saikosaponin D offers promising potential in anti-tumor therapy. This paper reviews recent studies on its anti-tumor effects, aiming to furnish new theoretical insights for clinical cancer treatments.

Design and synthesis of unique indole-benzosulfonamide oleanolic acid derivatives as potent antibacterial agents against MRSA.

The rapid emergence of antibiotic resistance and the scarcity of novel antibacterial agents have necessitated an urgent pursuit for the discovery and development of novel antibacterial agents against multidrug-resistant bacteria. This study involved the design and synthesis of series of novel indole-benzosulfonamide oleanolic acid (OA) derivatives, in which the indole and benzosulfonamide pharmacophores were introduced into the OA skeleton semisynthetically. These target OA derivatives show antibacterial activity against Staphylococcus strains in vitro and in vivo. Among them, derivative c17 was the most promising antibacterial agent while compared with the positive control of norfloxacin, especially against methicillin-resistant Staphylococcus aureus (MRSA) in vitro. In addition, derivative c17 also showed remarkable efficacy against MRSA-infected murine skin model, leading to a significant reduction of bacterial counts during this in vivo study. Furthermore, some preliminary studies indicated that derivative c17 could effectively inhibit and eradicate the biofilm formation, disrupt the integrity of the bacterial cell membrane. Moreover, derivative c17 showed low hemolytic activity and low toxicity to mammalian cells of NIH 3T3 and HEK 293T. These aforementioned findings strongly support the potential of novel indole-benzosulfonamide OA derivatives as anti-MRSA agents.

Millettia dubia De Wild. (Fabaceae): Structural analysis of the oleanane-type glycosides and stimulation of the sweet taste receptors TAS1R2/TAS1R3.

From the root barks of a Central African tree Millettia dubia De Wild. (Fabaceae), ten previously undescribed oleanane-type glycosides were isolated by various chromatographic protocols. Their structures were elucidated by spectroscopic methods, mainly 2D NMR experiments and mass spectrometry, as mono- and bidesmosidic glycosides of mesembryanthemoidigenic acid, hederagenin and oleanolic acid. The stimulation of the sweet taste receptor TAS1R2/TAS1R3 by these glycosides was evaluated, and structure/activity relationships were proposed. Two of them showed an agonist effect on TAS1R2/TAS1R3.

Recent advances in the chemistry and biology of oleanolic acid and its derivatives.

The pentacyclic triterpenes represent a significant class of plant bioactives with a variety of structures and a wide array of biological activities. These are biosynthetically produced via the mevalonate pathway although occasionally mixed pathways may also occur to introduce structural divergence. Oleanolic acid is one of the most explored bioactive from this class of compounds and possesses a broad spectrum of pharmacological and biological activities including liver protection, anti-cancer, atherosclerosis, anti-inflammation, antibacterial, anti-HIV, anti-oxidative, anti-diabetic etc. This review provides an overview of the latest research findings, highlighting the versatile medicinal and biological potential of oleanolic and its future prospects.

Chikusetsu Saponin IVa liposomes modified with a retro-enantio peptide penetrating the blood-brain barrier to suppress pyroptosis in acute ischemic stroke rats.

BACKGROUND: The therapeutic strategies for acute ischemic stroke were faced with substantial constraints, emphasizing the necessity to safeguard neuronal cells during cerebral ischemia to reduce neurological impairments and enhance recovery outcomes. Despite its potential as a neuroprotective agent in stroke treatment, Chikusetsu saponin IVa encounters numerous challenges in clinical application. RESULT: Brain-targeted liposomes modified with THRre peptides showed substantial uptake by bEnd. 3 and PC-12 cells and demonstrated the ability to cross an in vitro blood-brain barrier model, subsequently accumulating in PC-12 cells. In vivo, they could significantly accumulate in rat brain. Treatment with C-IVa-LPs-THRre notably reduced the expression of proteins in the P2RX7/NLRP3/Caspase-1 pathway and inflammatory factors. This was evidenced by decreased cerebral infarct size and improved neurological function in MCAO rats. CONCLUSION: The findings indicate that C-IVa-LPs-THRre could serve as a promising strategy for targeting cerebral ischemia. This approach enhances drug concentration in the brain, mitigates pyroptosis, and improves the neuroinflammatory response associated with stroke.

Saikosaponin A Ameliorates Metabolic Inflammation and Intestinal Barrier Damage in DIO Mice through the Nrf2/ARE Pathway.

BACKGROUND: Obesity is linked to impaired intestinal barrier function and inflammation. Saikosaponin A (SSA), a triterpene saponin from Bupleurum chinense, has shown beneficial effects on intestinal colitis in mice. However, the mechanisms underlying SSA's protective effects against obesity are not fully understood. OBJECTIVE: To investigate the effects of SSA on body weight, metabolic disturbances, and intestinal health in diet-induced obese (DIO) mice, and to elucidate the potential mechanisms involved. METHODS: In the in vivo study, DIO mice were supplemented with SSA. Body weight, fasting blood glucose, and metabolic parameters were measured. Intestinal barrier function and inflammation were assessed. In the in vitro study, intestinal epithelial cells were treated with palmitic acid and lipopolysaccharide to induce inflammation. SSA was then administered to evaluate its effects on cell barrier integrity and inflammatory responses. The role of the nuclear factor-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway was investigated by silencing Nrf2. RESULTS: SSA supplementation significantly (p < 0.05) decreased body weight and fasting blood glucose levels in DIO mice, and markedly improved metabolic disturbances. This treatment also enhanced intestinal barrier function and reduced metabolic inflammation, likely through increased antioxidant capacity of intestinal epithelial cells via activation of the Nrf2/ARE signaling pathway. In vitro, SSA maintained cell barrier integrity and reduced inflammatory responses by activating the Nrf2/ARE signaling pathway, decreasing intracellular reactive oxygen species content, and increasing transepithelial electrical resistance. However, silencing Nrf2 abolished SSA's protective effects. CONCLUSION: SSA enhances the antioxidant capacity of intestinal epithelial cells, maintains intestinal barrier integrity, and reduces intestinal inflammation in DIO mice through the activation of the Nrf2/ARE signaling pathway. These findings offer new insights into the protective role of SSA in obesity and metabolic diseases.

SZC010 suppresses breast cancer development by regulating the PI3K/Akt/NF-κB signaling pathway.

BACKGROUND: Breast cancer has become one of the leading causes of cancer deaths and is the most frequently diagnosed cancer among females worldwide. Despite advances in breast cancer therapy, metastatic disease in most patients will eventually progress due to the development of de novo or secondary resistance. Thus, it is extremely important to seek novel drugs with high effectiveness and low toxicity for systematic therapy. METHODS: We applied a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in this study to analyze and evaluate the cytotoxic activity of oleanolic acid (OA) and its derivatives in three types of breast cancer cell lines (MDA-MB-231, MCF-7, and MDA-MB-453). A flow cytometry assay was performed to access the mechanisms of apoptosis and cell cycle analysis in SZC010 in MDA-MB-453 cells. Apoptosis- and cyclin-related proteins were evaluated by western blot. The key proteins of the NF-κB and PI3K-Akt-mTOR signaling pathway were also evaluated by western blot. RESULTS: Our results revealed that all OA derivatives were more effective than OA in three types of breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-453). Among these seven OA derivatives, SZC010 exhibited the most potent cytotoxicity in MDA-MB-453 cells. Additionally, we observed that SZC010 treatment induced dose-and time-dependent growth inhibition in MDA-MB-453 cells. Furthermore, we demonstrated that SZC010 induced growth arrest in the G2/M phase and apoptosis by inhibition of NF-κB activation via the PI3K/Akt/mTOR signaling pathway. CONCLUSIONS: Our data indicate that the novel OA derivative, SZC010, has great potential in breast cancer therapy.

Symplosaponins A-D: New acylated oleanane-type triterpene saponins from Symplocos cochinchinensis and their hepatoprotective effect.

Four new acylated oleanane-type triterpene saponins, symplosaponins A-D (1-4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5-9), 2-methoxy-4-prop-1-enylphenyl-1-O-ß-D-apiofuranosyl-(1 â†’ 6)-ß-D-glucopyranoside (5), and 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-ß-d-xylopyranosyl-(1 â†’ 6)-O-ß-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (-)-secoisolariciresinol-O-ß-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner.

Oleanolic acid-3-glucoside, a synthetic oleanane-type saponin, ameliorates methylmercury-induced dysfunction of synaptic transmission in mice.

Methylmercury (MeHg) is widely distributed in nature and is known to cause neurotoxic effects. This study aimed to examine the anti-MeHg activity of oleanolic acid-3-glucoside (OA3Glu), a synthetic oleanane-type saponin derivative, by evaluating its effects on motor function, pathology, and electrophysiological properties in a mouse model of MeHg poisoning. Mice were orally administered 2 or 4 mg·kg-1·d-1 MeHg with or without 100 µg·kg-1·d-1 OA3Glu 5x/week for four weeks. Motor function was evaluated using beam-walking and dynamic weight-bearing (DWB) tests. High-dose MeHg exposure significantly increased the frequency of stepping off the hind leg while crossing the beam in the beam-walking test, and increased weight on forelegs when moving freely in the DWB test. OA3Glu treatment alleviated motor abnormality caused by high-dose MeHg exposure in both motor function tests. Additionally, OA3Glu treatment reduced the number of contracted Purkinje cells frequently observed in the cerebellum of MeHg-treated groups, although cerebrum histology was similar in all experimental groups. The synaptic potential amplitude in the cerebellum decreased as MeHg exposure increased, which was restored by OA3Glu treatment. Even in the cerebrum, where the effects of MeHg were not observed, the amplitude of the field potential was suppressed with increasing MeHg exposure but was restored with OA3Glu treatment. Taken together, the study findings suggest that OA3Glu improves neurotransmission and movement disorders associated with MeHg exposure via protection of Purkinje cells in the cerebellum while ameliorating pre/post-synaptic deficits in the cerebral cortex in which no changes were observed at the tissue level, potentially providing a treatment to mitigate MeHg toxicity.

Alpha-Hederin induces incomplete autophagic injury in non-small cell lung cancer by interfering with the lysosomal acidification.

Lung cancer is the most common oncological disease worldwide, with non-small cell lung cancer accounting for approximately 85% of lung cancer cases. α-Hederin is a monodesmosidic triterpenoid saponin isolated from the leaves of Hedera helix L. or Nigella sativa and has been extensively studied for its antitumor activity against a variety of tumor cells. It has been suggested that α-Hederin is a potential regulator of autophagy and has high promise for application. However, the specific mechanism and characteristics of α-Hederin in regulating autophagy are not well understood. In this study, we confirmed the potential of α-Hederin application in lung cancer treatment and comprehensively explored the mechanism and characteristics of α-Hederin in regulating autophagy in lung cancer cells. Our results suggest that α-Hederin is an incomplete autophagy inducer that targets mTOR to activate the classical autophagic pathway, inhibits lysosomal acidification without significantly affecting the processes of autophagosome transport, lysosome biogenesis, autophagosome and lysosome fusion, and finally leads to impaired autophagic flux and triggers autophagic damage in NSCLC.

A multifunctional nanoplatform for chemotherapy and nanocatalytic synergistic cancer therapy achieved by amplified lipid peroxidation.

Traditional cancer chemotherapy suffers from low efficacy and severe side effects, limiting its use as a first-line treatment. To address this issue, we investigated a novel way to induce lipid peroxidation (LPO), which plays an essential role in ferroptosis and may be useful against cancer cells and tumors. In this study, a pH-responsive synergistic cancer therapy nanoplatform was prepared using CaCO3 co-loaded with oleanolic acid (OA) and lipoxygenase (LOX), resulting in the formation OLCaP NP. This nanoplatform exhibited good drug release properties in an acidic tumor environment owing to the presence of CaCO3. As a result of acidic stimulation at tumor sites, the OLCaP NP released OA and LOX. OA, a chemotherapeutic drug with anticancer activity, is already known to promote the apoptosis of cancer cells, and LOX is a natural enzyme that catalyzes the oxidation of polyunsaturated fatty acids, leading to the accumulation of lipid peroxides and promoting the apoptosis of cancer cells. More importantly, OA upregulated the expression of acyl-coenzyme A synthetase long-chain family member 4 (ACSL4), which promoted enzyme-mediated LPO. Based on our combined chemotherapy and nanocatalytic therapy, the OLCaP NP not only had remarkable antitumor ability but also upregulated ACSL4 expression, allowing further amplification of LPO to inhibit tumor growth. These findings demonstrate the potential of this nanoplatform to enhance the therapeutic efficacy against tumors by inducing oxidative stress and disrupting lipid metabolism, highlighting its clinical potential for improved cancer treatment. STATEMENT OF SIGNIFICANCE: This study presents a novel nanoplatform that combines oleanolic acid (OA), a chemotherapeutic drug, and lipoxygenase (LOX), which oxidizes polyunsaturated fatty acids to trigger apoptosis, for targeted cancer therapy. Unlike traditional treatments, our nanoplatform exhibits pH-responsive drug release, specifically in acidic tumor environments. This innovation enhances the therapeutic effects of OA and LOX, upregulating acyl-CoA synthetase long-chain family member 4 expression and amplifying lipid peroxidation to promote tumor cell apoptosis. Our findings significantly advance the existing literature by demonstrating a synergistic approach that combines chemotherapy and nanocatalytic therapy. The scientific impact of this work lies in its potential to improve cancer treatment efficacy and specificity, offering a promising strategy for clinical applications and future research in cancer therapy.

In-silico and in-vitro studies revealed alpha-amyrin as a potent pnhibitor of TLR2 for the therapeutics of bacterial infection and sepsis.

This study employed a multifaceted approach to investigate the inhibitory potential of alpha-amyrin against TLR2, a key player in bacterial infection and sepsis. A high-resolution TLR2 model was constructed using Swiss-MODEL, exhibiting excellent quality with 100% sequence identity and coverage. Cavity detection revealed five significant cavities on TLR2. Molecular docking identifies alpha-amyrin as a potent inhibitor, displaying a strong binding affinity of -8.6 kcal/mol. Comprehensive analyses, including ADMET predictions, PASS analysis, and SwissTargetPrediction, affirm alpha-amyrin's drug-like properties and diverse biological activities. Cytotoxicity assays on HEK-293 cells confirm its safety, and fluorescence-based inhibition assays provide empirical evidence of its inhibitory potency on TLR2 enzymatic activity. Further validations in HUVECs show a significant decrease in TLR2 mRNA expression (p<0.01) and activity (p<0.05) upon alpha-amyrin treatment. In conclusion, this integrative study positions alpha-amyrin as a promising therapeutic candidate for TLR2 inhibition, emphasizing its potential in combating bacterial infections with safety and efficacy.

Structure-Activity Relationship of Oleanane-Type Pentacyclic Triterpenoids on Nuclear Factor κB Activation and Intracellular Trafficking and N-Linked Glycosylation of Intercellular Adhesion Molecule-1.

In our previous study, two oleanane-type pentacyclic triterpenoids (oleanolic acid and maslinic acid) were reported to affect the N-glycosylation and intracellular trafficking of intercellular adhesion molecule-1 (ICAM-1). The present study was aimed at investigating the structure-activity relationship of 13 oleanane-type natural triterpenoids with respect to the nuclear factor κB (NF-κB) signaling pathway and the expression, intracellular trafficking, and N-glycosylation of the ICAM-1 protein in human lung adenocarcinoma A549 cells. Hederagenin, echinocystic acid, erythrodiol, and maslinic acid, which all possess two hydroxyl groups, decreased the viability of A549 cells. Celastrol and pristimerin, both of which possess an α,ß-unsaturated carbonyl group, decreased cell viability but more strongly inhibited the interleukin-1α-induced NF-κB signaling pathway. Oleanolic acid, moronic acid, and glycyrrhetinic acid interfered with N-glycosylation without affecting the cell surface expression of the ICAM-1 protein. In contrast, α-boswellic acid and maslinic acid interfered with the N-glycosylation of the ICAM-1 protein, which resulted in the accumulation of high-mannose-type N-glycans. Among the oleanane-type triterpenoids tested, α-boswellic acid and maslinic acid uniquely interfered with the intracellular trafficking and N-glycosylation of glycoproteins.

Saikosaponin D Inhibits Lung Metastasis of Colorectal Cancer Cells by Inducing Autophagy and Apoptosis.

Saikosaponin D (SSD), derived from Bupleurum falcatum L., has various pharmacological properties, including immunoregulatory, anti-inflammatory, and anti-allergic effects. Several studies have investigated the anti-tumor effects of SSD on cancer in multiple organs. However, its role in colorectal cancer (CRC) remains unclear. Therefore, this study aimed to elucidate the suppressive effects of SSD on CRC cell survival and metastasis. SSD reduced the survival and colony formation ability of CRC cells. SSD-induced autophagy and apoptosis in CRC cells were measured using flow cytometry. SSD treatment increased LC3B and p62 autophagic factor levels in CRC cells. Moreover, SSD-induced apoptosis occurred through the cleavage of caspase-9, caspase-3, and PARP, along with the downregulation of the Bcl-2 family. In the in vivo experiment, a reduction in the number of metastatic tumor nodules in the lungs was observed after the oral administration of SSD. Based on these results, SSD inhibits the metastasis of CRC cells to the lungs by inducing autophagy and apoptosis. In conclusion, SSD suppressed the proliferation and metastasis of CRC cells, suggesting its potential as a novel substance for the metastatic CRC treatment.