μM In HepG2 Cells Research Articles

PH-responsive supramolecular nanoparticles constructed by Cationic Pillar[5]arenes were used for drug delivery to enhance antitumor activity

ABSTRACT Nano-drug delivery systems have been widely used in antitumor therapy due to their good biocompatibility and low toxicity. However, improving drug-carrying properties and drug release from carriers remains a challenge. In this study, we successfully constructed pH-responsive supramolecular drug-carrying spherical nanoparticles by self-assembling D-alanine-modified water-soluble cationic pillar[5]arene (DAP5) and sodium laurate (SL) to form complexes in aqueous solution. The results demonstrated that DAP5 spherical nanoparticles loaded with doxorubicin hydrochloride (DOX HCl) exhibited an encapsulation rate of 60.0% and a drug loading capacity of 10.5%. These nanoparticles continuously released the drug in a weakly acidic environment that simulates tumour cells. Furthermore, SL⊂DAP5 exhibited good biocompatibility with human normal liver cells (L-02) (IC50 >10 μmol/L), while DOX⊂SL⊂DAP5 demonstrated stronger cytotoxicity against four tumour cells (Hela, HepG2, MGC-803, T-24) compared to free DOX. Notably, DOX⊂SL⊂DAP5 showed an IC50 of only 1.04 μM for HepG2 cells, which was approximately 30.32% of that of DOX (3.43 μM) after 24 hours of incubation. These findings provide valuable insights for the future development of supramolecular drug delivery systems, aiming to enhance drug utilisation and reduce toxic side effects in tumour treatment.

A newly synthesized thiosemicarbazide derivative trigger apoptosis rather than necroptosis on HEPG2 cell line.

Thiosemicarbazide derivatives have been the focus of scientists owing to their broad biological activities such as anticancer, antimicrobial, and anti-inflammatory. Herein, we designed and synthesized a new thiosemicarbazide derivative (TS-1) and evaluated its antiproliferative potential against the human hepatocellular carcinoma cell line (HEPG2) and human umbilical vein endothelial cell line (ECV-304). Also, it was aimed to investigate the necroptotic and apoptotic cell death effects of TS-1 in HEPG2 cells, and these effects were supported by molecular docking. The new synthesized compound structure was characterized using various spectroscopic methods such as FT-IR, 1 H-NMR, 13 C-NMR, and elemental analysis. The cytotoxic activity of the tested compound was measured by the MTT assay. Apoptotic and necroptotic properties of the TS-1 were evaluated by indirect immunoperoxidase method using antibodies against Ki-67, Bax, Bcl-2, caspase-3, caspase-8, caspase-9, RIP3, and RIPK1. Apoptotic and necroptotic effects of TS-1 were supported by molecular docking. Compound TS-1 was synthesized as a pure compound with a high yield. The effective value of TS-1 was 10 μM in HEPG2 cells. TS-1 did not show any cytotoxic effect on ECV-304. Caspase-3 and RIPK1 immunoreactivities were significantly increased in HEPG2 cells after being treated with TS-1. As the results of the molecular docking studies, the molecular docking showed that the TS-1 exhibits H-bond interaction with various significant amino acid residues in the active site of both RIPK1. It could be concluded that TS-1 could be a promising novel therapeutic agent by inducing apoptosis rather than necroptosis in HEPG2 cells.

Bioactive mixed-ligand zinc(II) complexes with 1H-tetrazole-5-acetic acid and oligopyridine derivatives

1H-tetrazole-5-acetic acid is bifunctional ligand that was employed for the synthesis of zinc(II) complexes in the presence of secondary ligands such as oligopyridines (dmphen – 4,7-dimethyl-1,10-phenanthroline, phendione – 1,10-phenanthroline-5,6-dione, phen – 1,10-phenanthroline, dmbipy – 2,2′-bi-4-picoline, bipy – 2,2′-bipyridine). Five new mixed-ligand zinc(II) complexes [Zn(dmphen)L]·H2O (1), [Zn(phendione)(H2O)L]·2H2O (2), [Zn(phen)L]·0,5H2O (3), {[Zn(dmbipy)L]·H2O}n (4) and [Zn(bipy)L]·H2O (5) have been synthesized and characterized by elemental analysis, IR spectroscopy and powder X-ray diffraction. All complexes have shown to possess thermal stability up to 250°C by thermogravimetric analysis, except for complexes 2 and 5, which have been stable up to 200°C. Crystal structures of polymeric complexes {[Zn(dmphen)(H2O)2L]·2H2O}n (1a) and 4 have been determined by single-crystal X-ray diffraction analysis. The effect of the compounds on viability of HepG-2, MCF–7 and MRC-5 cell lines has been investigated. Complex 2 was found to be the most cytotoxic with IC50 values of 6.4 ± 0.9 µM for HepG-2 cells and 2.6 ± 1.1 µM for MCF-7 cells. The antimicrobial activity of the complexes and ligands has been investigated against E. coli, S. aureus, P. italicum and C. steinii.

Chemical constituents of the stem of Marsypopetalum modestum and their bioactivities

Phytochemical investigation of Marsypopetalum modestum (Annonaceae) led to the isolation of a new phenylpropanoid glycoside, lyciumphenylpropanoid B (10), along with nine known compounds (1-9) from an aqueous methanolic extract of the stem. Most compounds are reported from this genus for the first time. The structures of the isolated compounds were elucidated using spectroscopic methods including NMR spectroscopy, high-resolution mass spectrometry, and quantum chemical electronic circular dichroism (ECD) calculations. Cytotoxic and antitubercular activities of several isolated compounds were evaluated. Dipyrithione (1) displayed anti-mycobacterial (MIC = 0.23 μM) and cytotoxic (IC50 = 0.8 μM in Hep G2 cells; 4.1 μM in HCT 116 cells) activities. Kelampayoside A (8) showed moderate cytotoxic activity against cancer cells.

Biotin-tagged cis-dichlorido-oxidovanadium(IV) complex for DNA crosslinking and photo-induced apoptotic cytotoxicity

Cis-dichlorido-oxidovanadium(IV) complexes [VO(dpa/L1)Cl2] (1, 2) of dipicolylamine (dpa, 1 as control species) and 5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoic acid (biotin)-appended dpa (L1, 2 as active species) were prepared and their anticancer activity studied. Single crystal X-ray diffraction analysis of complex 1 revealed a cis arrangement of two chloride ligands in a distorted octahedral geometry with VIVON3Cl2. The dpa ligand displayed a facial mode of coordination. The complexes were 1:1 electrolytic in an aqueous medium and showed a significant enhancement of conductivity on irradiation with visible light. Complex 2 having the biotin moiety showed cytotoxicity in visible light of 400–700 nm giving IC50 value of 15.0(±0.2) µM in HeLa cells and 5.0(±1.2) μM in HepG2 cells. The complex did not show any apparent generation of reactive oxygen species (ROS) in dichlorofluorescein diacetate (DCFDA) assay. The complex displayed apoptotic photo-induced cytotoxicity following DNA crosslinking pathway as ascertained from the comet assay.

Synthesis and Antiviral Evaluation of (1,4-Disubstituted-1,2,3-Triazol)-(E)-2-Methyl-but-2-Enyl Nucleoside Phosphonate Prodrugs.

A series of hitherto unknown (1,4-disubstituted-1,2,3-triazol)-(E)-2-methyl-but-2-enyl nucleosides phosphonate prodrugs bearing 4-substituted-1,2,3-triazoles were prepared in a straight approach through an olefin acyclic cross metathesis as the key synthetic step. All novel compounds were evaluated for their antiviral activities against HBV, HIV and SARS-CoV-2. Among these molecules, only compound 15j, a hexadecyloxypropyl (HDP)/(isopropyloxycarbonyl-oxymethyl)-ester (POC) prodrug, showed activity against HBV in Huh7 cell cultures with 62% inhibition at 10 μM, without significant cytotoxicity (IC50 = 66.4 μM in HepG2 cells, IC50 = 43.1 μM in HepG2 cells) at 10 μM.

Ferritinophagy-Mediated ROS Production Contributed to Proliferation Inhibition, Apoptosis, and Ferroptosis Induction in Action of Mechanism of 2-Pyridylhydrazone Dithiocarbamate Acetate.

Reactive oxygen species (ROS) production is involved in the mechanism of action of a number of drugs, but the biological effects of ROS remain to be clarified. Furthermore, ferroptosis involves iron-dependent ROS production that may be derived from ferritinophagy; however, the association between ferroptosis and ferritinophagy has not been fully established. The present study demonstrated that dithiocarbamate derivatives (iron chelators) exhibited antineoplastic properties involving ferritinophagy induction, but whether the underlying mechanisms involved ferroptosis was unknown. To gain insight into the underlying mechanism, a dithiocarbamate derivative, 2-pyridylhydrazone dithiocarbamate s-acetic acid (PdtaA), was prepared. An MTT assay demonstrated that PdtaA inhibited proliferation involving ROS production (IC50 = 23.0 ± 1.5 μM for HepG2 cells). A preliminary mechanistic study revealed that PdtaA induced both apoptosis and cell cycle arrest. Notably, PdtaA also induced ferroptosis via downregulation of GPx4 and xCT, which was first reported for a dithiocarbamate derivative. Moreover, these cellular events were associated with ROS production. To explore the origin of ROS, expression of the ferritinophagy-related genes, ferritin, and nuclear receptor coactivator (NCOA4) were measured. Immunofluorescence and western blotting analysis indicated that PdtaA-induced ferritinophagy may contribute to ROS production. To investigate the role of ferritinophagy, autophagy inhibitor 3-methyladenin or genetic knockdown of NCOA4 was employed to inhibit ferritinophagy, which significantly neutralized the action of PdtaA in both apoptosis and ferroptosis. Taken together, PdtaA-induced cell cycle arrest, apoptosis, and ferroptosis were associated with ferritinophagy.

Interaction of curcumin on cisplatin cytotoxicity in HeLa and HepG2 carcinoma cells

Background and Aims: Our study aimed to evaluate how curcumin affect cisplatin cytotoxicity in human cervical carcinoma (HeLa), human hepatocellular carcinoma (HepG2), and Chinese hamster lung fibroblast (V79) cells. Methods: The cytotoxicity was evaluated by MTT assay. Results: The IC50 values of curcumin were 404 μM and 320 μM in HeLa cells; 236 μM and 98.3 μM in HepG2 cells; 877 μM and 119 μM in V79 cells; for 24 h and 48 h, respectively. The IC50 values of cisplatin were 22.4 μM and 12.3 μM in HeLa cells; 25.5 μM and 7.7 μM in HepG2 cells; 15.4 μM and 4.9 μM in V79 cells; for 24 h and 48 h, respectively. Curcumin significantly decreased cisplatin cytotoxicity at 500 μM in HeLa cells and above 250 μM and 125 μM in HepG2 cells, for 24 h and 48 h, respectively. In V79 cells, curcumin significantly decreased the IC50 values of cisplatin above 500 μM and 125 μM for 24 h and 48 h. Conclusion: The results might contribute to the anticancer effect of the curcumin-cisplatin combination in cervical and hepatocellular carcinoma, but in order to support this result and determine its interactions with antineoplastic drugs, further studies are needed.

A spirostanol glycoside from wild yam (Diosccorea villosa) extract and its cytostatic activity on three cancer cells

A spirostanol glycoside, (25R)-spirost-5-en-3β-ol 3-O-α-L-rhamnopyranosyl -(1→2)-O-[β-D-glucopyranosyl -(1→4)]-β-D-glucopyranoside, was isolated from wild yam (Dioscorea villosa) extract with reversed-phase preparative HPLC. This was the first time found in yams (Dioscorea species). The structure was identified by LC-MS, 1H- and 13C-NMR. Cytostatic activities of the isolated saponin on Hep G2, HEK293 and MCF7 cells were estimated. Growth of these cells was inhibited as higher concentration of the compound was used. The IC50 values of the isolated spirostanol glycoside and its aglycon, diosgenin, were 9.02 and 23.91 μM for Hep G2 cells, 13.21 and 27.31 μM for HEK293 cells, and 16.74 and 35.38 μM for MCF7 cells, respectively. The isolated compound had significantly higher active intensity than diosgenin.

Synthesis, in vitro ADME profiling and in vivo pharmacological evaluation of novel glycogen phosphorylase inhibitors

A small set of indole-2-carboxamide derivatives identified from a high-throughput screening campaign has been described as a novel, potent, and glucose-sensitive inhibitors of glycogen phosphorylase a (GPa). Among this series of compounds, compound 2 exhibited moderate GP inhibitory activity (IC50 = 0.29 μM), good cellular efficacy (IC50 = 3.24 μM for HepG2 cells and IC50 = 7.15 μM for isolated rat hepatocytes), together with good absorption, distribution, metabolism, and elimination (ADME) profiles. The in vivo animal study revealed that compound 2 significantly inhibited an increase of fasting blood glucose level in adrenaline-induced diabetic mice.

Design, Synthesis, and Biological Application of Novel Photoaffinity Probes of Dihydropyridine Derivatives, BAY R3401.

To explore the molecular mechanisms of BAY R3401, four types of novel photoaffinity probes bearing different secondary tags were synthesized. Their potency for glycogenolysis was evaluated in primary human liver HL-7702 cells and HepG2 cells. Probe 2d showed the best activity in primary human liver HL-7702 cells and HepG2 cells, with IC50 values of 4.45 μM and 28.49 μM, respectively. Likewise, probe 5d showed IC50 values of 6.46 μM in primary human liver HL-7702 cells and 15.29 μM in HepG2 cells, respectively. Photoaffinity labeling experiments were also performed and protein bands larger than 170 kDa were specifically tagged by probe 2d. The results suggest that the synthesized probe 2d might be a very promising tool for the isolation of the target proteins of BAY R3401.

Elucidation of interaction mechanism of ellagic acid to the integrin linked kinase

Integrin-linked kinase (ILK) is a member of Ser/Thr kinase which interacts to the cytoplasmic domain of β-integrins, and thereby induces apoptosis. ILK is considered as potential drug target because it's direct involvement in the tumor progression. Here, we have performed molecular docking followed by 100 ns MD simulation to understand the mechanism of interaction of ILK with the ellagic acid (EA). EA is well known for its antiproliferative and antioxidant properties in cancer cell lines and animal models. We have observed that EA binds to the active site cavity of ILK and causes conformational changes in the ILK structure. The orientation of EA in the active pocket of ILK showed to have least RMSD values and stable. The average binding energy ILK-EA complex calculated during MMPBSA was −191.267 kJ/mol, indicating a relatively strong binding affinity. The actual binding affinity of EA to ILK was measured by fluorescence spectroscopy and Kb and n values were 9.28 μM and 1.9264 (~2), respectively. The IC50 values for EA were 26.22 ± 0.12 μM for MCF-7 and 38.45 ± 2.42 μM for HepG2 cells, estimated by MTT assay. Our findings are helpful to design EA-based novel inhibitors of ILK which have potential to attenuate tumor progression.

Curative effect of arjunolic acid from Terminalia arjuna in non-alcoholic fatty liver disease models

The prevalence of Non Alcoholic Fatty Liver Disease (NAFLD) is increasing globally. Terminalia arjuna W. & Arn. (Combretaceae) is an endemic tree found in India and Sri Lanka and used traditionally for its cardioprotective and hepatoprotective effects. Arjunolic acid (AA) is an oleanane triterpenoid found mainly in the heartwood of T. arjuna. This study was aimed to evaluate the hepatoprotective effect of AA using cellular and rodent models of NAFLD. AA was isolated from the ethyl acetate extract of the heartwood of T. arjuna. The structure of AA was confirmed by physical and spectroscopic data. Steatosis was induced in HepG2 cells using palmitate-oleate mixture and the effects of AA on triglyceride accumulation and lipotoxicity were assessed. In vivo effect of AA on NAFLD was assessed using HFD fed rats. The treatment with AA did not affect the cell viability upto 100 μM and showed GI25 value of 379.9 μM in HepG2 cells. The treatment with AA significantly lowered the ORO concentration by 35.98% and triglyceride accumulation by 66.36% at 50 μM concentration (P < 0.005) compared to the vehicle treated group. The treatment with AA also reduced the leakage of ALT and AST by 61.11 and 48.29% in a significant manner (P < 0.005). The in vivo findings clearly demonstrated that the animals treated with AA at 25 and 50 mg/kg concentrations showed a significant decrease in the levels of transaminases, phosphatase and GGT (P < 0.005). In the liver, the expression of PPARα and FXRα expressions were upregulated, while PPARγ expression was downregulated by the treatment with AA. The liver histology of the animals showed reduction in steatosis and MNC infiltration. These preliminary evidences suggested that AA might be a promising lead to treat NAFLD. Future robust scientific studies on AA will lead to tailoring it for the treatment of NAFLD.

High Concentrations of Rosiglitazone Reduce mRNA and Protein Levels of LRP1 in HepG2 Cells.

Low-density lipoprotein receptor-related protein 1 (LRP1) is an endocytic receptor involved in the uptake of a variety of molecules, such as apoE, α2-macroglobulin, and the amyloid β peptide (Aβ), for either transcellular transport, protein trafficking or lysosomal degradation. The LRP1 gene can be transcribed upon activation of peroxisome proliferator receptor activated-γ (PPARγ) by the potent PPARγ agonist, rosiglitazone (RGZ). In previous studies, RGZ was shown to upregulate LRP1 levels in concentrations between 0.1 and 5 μM in HepG2 cells. In this study, we sought to replicate previous studies and to investigate the molecular mechanism by which high concentrations of RGZ reduce LRP1 levels in HepG2 cells. Our data confirmed that transcriptional activation of LRP1 occurred in response to RGZ at 3 and 10 μM, in agreement with the study reported by Moon et al. (2012a). On the other hand, we found that high concentrations of RGZ decreased both mRNA and protein levels of LRP1. Mechanistically, transcriptional dysregulation of LRP1 was affected by the downregulation of PPARγ in a time- and concentration-dependent manner. However, downregulation of PPARγ was responsible for only 40% of the LRP1 reduction and thereby the remaining loss of LRP1 (60%) was found to be through degradation in the lysosomal system. In conclusion, our findings demonstrate the mechanisms by which high concentrations of RGZ caused LRP1 levels to be reduced in HepG2 cells. Taken together, this data will be helpful to better explain the pharmacological modulation of this pivotal membrane receptor by PPARγ agonists.

Hepatotoxicity of Eupatorium adenophorum extracts and the identification of major hepatotoxic components

Eupatorium adenophorum can induce liver toxicity in animals. For the safe utilisation of the weed, the hepatotoxic components need to be discovered. In this study, in vitro hepatotoxicity of different extracts from E. adenophorum were determined on human hepatocyte cell line L02 and hepatocellular carcinoma cell line HepG2. The results showed that water extracts of E. adenophorum exhibited no hepatotoxicity in vitro while high concentrations of the organic solvent extracts had obvious hepatotoxicity. Sesquiterpenes may contribute to the toxicity based on the comparison of composition analysis. Three cadinene sesquiterpenes were purified and identified as 9-oxo-10,11-dehydroageraphorone, 10Hα-9-oxo-ageraphorone and 10Hβ-9-oxo-ageraphorone. In vitro hepatotoxic effects of these components were investigated, the IC50 of the three compounds were 122.53, 87.52, and 108.80 μM in L02 cells and 151.92, 104.48, and 138.08 μM in HepG2 cells by Cell Counting Kit-8 (CCK-8) assay. The three components were confirmed to be, at least partial, hepatotoxic components.

In vitro evaluation of ruthenium complexes for photodynamic therapy

BackgroundPhotodynamic therapy (PDT) is a promising anti-tumor treatment strategy. Photosensitizer is one of the most important components of PDT. In this work, the anticancer activities of PDT mediated by six new ruthenium porphyrin complexes were screened. The mechanisms of the most efficacious candidate were investigated. MethodsPhotocytotoxicity of the six porphyrins was tested. The most promising complex, Rup-03, was further investigated using Geimsa staining, which indirectly detects reactive oxygen species (ROS) and subcellular localization. Mitochondrial membrane potential (MMP), cell apoptosis, DNA fragmentation, c-Myc gene expression, and telomerase activities were also assayed. ResultsRup-03 and Rup-04 had the lowest IC50 values. Rup-03 had an IC50 value of 29.5±2.3μM in HepG2 cells and 59.0±6.1μM in RAW264.7 cells, while Rup-04 had an IC50 value of 40.0±3.8μM in SGC-7901 cells. The complexes also induced cellular morphological changes and impaired cellular ability to scavenge ROS, and accumulated preferentially in mitochondria and endoplasmic reticulum. Rup-03 reduced MMP levels, induced apoptosis, and repressed both c-Myc mRNA expression and telomerase activity in HepG2 cells. ConclusionsAmong six candidates, Rup-03-mediated PDT is most effective against HepG2 and RAW264.7, with a similar efficacy as that of Rup-04-mediated PDT against SGC-7901 cells. Repression of ROS scavenging activities and c-Myc expression, which mediated DNA damage-induced cell apoptosis and repression of telomerase activity, respectively, were found to be involved in the anticancer mechanisms of Rup-03.

Synthesis and biological evaluation of novel hydrogen sulfide releasing glycyrrhetic acid derivatives

A series of hybrids, which are composed of glycyrrhetic acid (GA) and slowly hydrogen sulfide-releasing donor ADT-OH, were designed and synthesized to develop anticancer and anti-inflammatory agents. Most of the compounds, whose inhibitory rates were comparable to or higher than those of GA and aspirin, respectively, significantly inhibited xylene-induced ear edema in mice. Especially, compound V4 exhibited the most potent inhibitory rate of 60.7%. Furthermore, preliminary structure–activity relationship studies demonstrated that 3-substituted GA derivatives had stronger anti-inflammatory activities than the corresponding 3-unsubstituted GA derivatives. In addition, anti-proliferative activities of compounds V1−9 were evaluated in three different human cancer cell lines. Compound V4 showed the most high potency against all three tumor cell lines with IC50 values ranging from 10.01 μM in Hep G2 cells to 17.8 μM in MDA-MB-231 cells, which were superior to positive GA.

Indirubin 3'-(O-oxiran-2-ylmethyl)oxime: a novel anticancer agent.

Indirubin is a potent inhibitor of cell cycle-related protein kinases by binding to the ATP-binding site and thus is a promising compound for development as an antitumor drug. We prepared indirubin 3'-(O-oxiran-2-ylmethyl)oxime (Epox/Ind), in which the ATP-binding site orientated part was attached by non-specific alkylating group. The IC50 value of Epox/Ind at 1.7 μM in HepG2 cells is comparable to that of cisplatin (4.0 μM). Furthermore, Epox/Ind was shown to be metabolized by a HepG2 cell lysate into indirubin 3'-(O-2,3-dihydroxypropyl)oxime (E804), the sole extractable metabolite. The lower toxicity of this metabolite may explain the lack of cytotoxicity of 1 μM Epox/Ind observed in HepG2 cells beyond an initial loss of viability in the first 24h of treatment.

Guttiferone F from the fruit of Garcinia multiflora and its anti-hepatocellular carcinoma activity

Garcinia multiflora is an evergreen arbor, which belongs to the family of Guttiferae. It grows mainly at the lower altitudes of the mountains in the Hengchun Peninsula, which is in southern Taiwan. In this study, bioactivity-guided screening was conducted to evaluate the anti-hepatocellular carcinoma bioactivity of the fruit's methanol extract of G. multiflora. The methanol extract residue was partitioned with various solvents. It was then separated and purified using flash chromatography. The active component was confirmed to be guttiferone F. In our present study, cytotoxicity assay revealed that the IC50 of guttiferone F was 14.15±2.36μM in PLC/PRF/5 cells, 10.17±0.51μM in HepG2 cells and 9.71±1.28μM in Hep3B cells. In the in vitro anticancer study, we found guttiferone F induced apoptosis by up-regulating cleaved pro-caspase-3 and PARP expressions in PLC/PRF/5 cells. The antitumor potency is similar to sorafenib, a therapeutic drug for liver cancer. Further in vivo study showed that guttiferone F inhibits minor tumor growth on s.c. xenograft tumor of human liver cancer cell line in female SCID mice. Although antitumor efficiency of guttiferone F is not superior to sorafenib, the dose (i.p., 25mg/kg×5days) is proved safe to animal. According to our studies, guttiferone F can be a promising lead for liver cancer therapy and become a new liberator for liver cancer patients after modification of the drug.

Synthesis, characterization and biological studies of diosgenyl analogues

A series of optical amino acid diosgenyl esters and diosgenyl salicylate conjugates were designed and synthesized to develop new anticancer and anti-inflammatory agents. The analogue 9c that contains an 6-aminohexanoic acid residue at C-3 of diosgenin exhibits higher potency against all three tumor cell lines with IC50 values ranging from 4.7μM in C26 cells to 14.6μM in Hep G2 cells. In addition, seven of newly synthesized compounds significantly inhibit xylene-induced ear edema and exhibit comparable or better anti-inflammatory activities than those of diosgenin and aspirin. Furthermore, preliminary structure–activity relationship studies demonstrate that diosgenyl salicylate conjugates have stronger anti-inflammatory activities than amino acid diosgenyl esters.