Human Liver Carcinoma HepG2 Cells Research Articles

Cadmium Chloride Induces DNA Damage and Apoptosis of Human Liver Carcinoma Cells via Oxidative Stress.

Cadmium is a heavy metal that has been shown to cause its toxicity in humans and animals. Many documented studies have shown that cadmium produces various genotoxic effects such as DNA damage and chromosomal aberrations. Ailments such as bone disease, renal damage, and several forms of cancer are attributed to overexposure to cadmium. Although there have been numerous studies examining the effects of cadmium in animal models and a few case studies involving communities where cadmium contamination has occurred, its molecular mechanisms of action are not fully elucidated. In this research, we hypothesized that oxidative stress plays a key role in cadmium chloride-induced toxicity, DNA damage, and apoptosis of human liver carcinoma (HepG2) cells. To test our hypothesis, cell viability was determined by MTT assay. Lipid hydroperoxide content stress was estimated by lipid peroxidation assay. Genotoxic damage was tested by the means of alkaline single cell gel electrophoresis (Comet) assay. Cell apoptosis was measured by flow cytometry assessment (Annexin-V/PI assay). The result of MTT assay indicated that cadmium chloride induces toxicity to HepG2 cells in a concentration-dependent manner, showing a 48 hr-LD50 of 3.6 µg/mL. Data generated from lipid peroxidation assay resulted in a significant (p < 0.05) increase of hydroperoxide production, specifically at the highest concentration tested. Data obtained from the Comet assay indicated that cadmium chloride causes DNA damage in HepG2 cells in a concentration-dependent manner. A strong concentration-response relationship (p < 0.05) was recorded between annexin V positive cells and cadmium chloride exposure. In summary, these in vitro studies provide clear evidence that cadmium chloride induces oxidative stress, DNA damage, and programmed cell death in human liver carcinoma (HepG2) cells.

Polysaccharide from Pleurotus nebrodensis induces apoptosis via a mitochondrial pathway in HepG2 cells.

A novel alkali extractable polysaccharide (designated as PNA-2) was purified from Pleurotus nebrodensis and the effects of purified PNA-2 on the proliferation and apoptosis of human hepatic cancer cells (HepG2) were investigated in this study. The results of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay indicated that PNA-2 inhibited the proliferation of HepG2 cells by apoptosis induction, which was also characterized using scanning electron microscopy (SEM). Moreover, the expression of apoptosis-associated mRNA, proteins and the cell-cycle arrest at the G0/G1 phase was determined using RT-qPCR, Western blot and flow cytometry, respectively. A notable inhibition of the migration rate of PNA-2-treated HepG2 cells was observed using a cell scratch assay. DNA damage was observed using a comet assay and AO/EB staining in HepG2 cells, which were exposed to PNA-2. Induction of the mitochondria-mediated intrinsic apoptotic pathway by PNA-2 was indicated by the loss of mitochondrial membrane potential (ΔΨm), Bcl-2 dysregulation and cytochrome c release. All the results suggested that the mitochondria-mediated intrinsic apoptotic pathway could be involved in PNA-2-mediated apoptosis of human liver carcinoma cells HepG2. Finally, the results indicated that PNA-2 significantly suppressed tumor growth in HepG2 tumor-bearing mice, indicating that PNA-2 may be developed as a candidate drug or functional food factor to prevent or treat liver cancer.

Trehalose-Based Block Copolycations Promote Polyplex Stabilization for Lyophilization and in Vivo pDNA Delivery.

The development and thorough characterization of nonviral delivery agents for nucleic acid and genome editing therapies are of high interest to the field of nanomedicine. Indeed, this vehicle class offers the ability to tune chemical architecture/biological activity and readily package nucleic acids of various sizes and morphologies for a variety of applications. Herein, we present the synthesis and characterization of a class of trehalose-based block copolycations designed to stabilize polyplex formulations for lyophilization and in vivo administration. A 6-methacrylamido-6-deoxy trehalose (MAT) monomer was synthesized from trehalose and polymerized via reversible addition–fragmentation chain transfer (RAFT) polymerization to yield pMAT43. The pMAT43 macro-chain transfer agent was then chain-extended with aminoethylmethacrylamide (AEMA) to yield three different pMAT-b-AEMA cationic-block copolymers, pMAT-b-AEMA-1 (21 AEMA repeats), -2 (44 AEMA repeats), and -3 (57 AEMA repeats). These polymers along with a series of controls were used to form polyplexes with plasmids encoding firefly luciferase behind a strong ubiquitous promoter. The trehalose-coated polyplexes were characterized in detail and found to be resistant to colloidal aggregation in culture media containing salt and serum. The trehalose-polyplexes also retained colloidal stability and promoted high gene expression following lyophilization and reconstitution. Cytotoxicity, cellular uptake, and transfection ability were assessed in vitro using both human glioblastoma (U87) and human liver carcinoma (HepG2) cell lines wherein pMAT-b-AEMA-2 was found to have the optimal combination of high gene expression and low toxicity. pMAT-b-AEMA-2 polyplexes were evaluated in mice via slow tail vein infusion. The vehicle displayed minimal toxicity and discouraged nonspecific internalization in the liver, kidney, spleen, and lungs as determined by quantitative polymerase chain reaction (qPCR) and fluorescence imaging experiments. Hydrodynamic infusion of the polyplexes, however, led to very specific localization of the polyplexes to the mouse liver and promoted excellent gene expression in vivo.

Theoretical investigation, biological evaluation and VEGFR2 kinase studies of metal(II) complexes derived from hydrotris(methimazolyl)borate

The reaction of soft tripodal scorpionate ligand, sodium hydrotris(methimazolyl)borate with M(ClO4)2·6H2O [MMn(II), Ni(II), Cu(II) or Zn(II)] in methanol leads to the cleavage of B–N bond followed by the formation of complexes of the type [M(MeimzH)4](ClO4)2·H2O (1–4), where MeimzH=methimazole. All the complexes were fully characterized by spectro-analytical techniques. The molecular structure of the zinc(II) complex (4) was determined by X-ray crystallography, which supports the observed deboronation reaction in the scorpionate ligand with tetrahedral geometry around zinc(II) ion. The electronic spectra of complexes suggested tetrahedral geometry for manganese(II) and nickel(II) complexes, and square-planar geometry for copper(II) complex. Frontier molecular orbital analysis (HOMO–LUMO) was carried out by B3LYP/6-31G(d) to understand the charge transfer occurring in the molecules. All the complexes exhibit significant antimicrobial activity against Gram (−ve) and Gram (+ve) bacterial as well as fungal strains, which are quite comparable to standard drugs streptomycin and clotrimazole. The copper(II) complex (3) showed excellent free radical scavenging activity against DPPH in all concentration with IC50 value of 30μg/mL, when compared to the other complexes. In the molecular docking studies, all the complexes showed hydrophobic, π-π and hydrogen bonding interactions with BSA. The cytotoxic activity of the complexes against human hepatocellular liver carcinoma (HepG2) cells was assessed by MTT assay, which showed exponential responses toward increasing concentration of complexes.

Novel glycol chitosan-based polymeric gene carrier synthesized by a Michael addition reaction with low molecular weight polyethylenimine

A glycol chitosan-based polymer that spontaneously assembles with plasmid DNA into nanorods was evaluated as a non-viral vector for gene delivery. Glycol chitosan–methyl acrylate-polyethylenimine (GMP) was synthesized by grafting polyethylenimine onto glycol chitosan via amidation after Michael addition using methyl acrylate. Gel retardation and PicoGreen assay experiments showed complete complex formation with plasmid DNA. GMP/pDNA complexes were characterized using biophysical techniques and were found to be positively charged rod-shape structures with widths in the nanometer scale and lengths in the micrometer scale. Transfection efficiency and cytotoxicity of GMP polymer was evaluated in human epithelial ovary carcinoma (HeLa) cells, human embryonic kidney 293 (HEK293) cells, and human hepatocellular liver carcinoma (HepG2) cells, in comparison to high molecular weight polyethylenimine, a commonly used transfection reagent. Intracellular polymer uptake was compared and confirmed by confocal microscopy. The results demonstrate that GMP, a hybrid polymer of glycol chitosan grafted with branched polyethylenimine, may serve as a promising vehicle for efficient gene delivery.

Shape Effect on Particle-Lipid Bilayer Membrane Association, Cellular Uptake, and Cytotoxicity.

Although computer simulation and cell culture experiments have shown that elongated spherical particles can be taken up into cells more efficiently than spherical particles, experimental investigation on effects of these different shapes over the particle-membrane association has never been reported. Therefore, whether the higher cellular uptake of an elongated spherical particles is a result of a better particle-membrane association as suggested by some calculation works or a consequence of its influence on other cellular trans-membrane components involved in particle translocation process, cannot be concluded. Here, we study the effect of particle shape on the particle-membrane interaction by monitoring the association between particles of various shapes and lipid bilayer membrane of artificial cell-sized liposomes. Among the three shaped lanthanide-doped NaYF4 particles, all with high shape purity and uniformity, similar crystal phase, and surface chemistry, the elongated spherical particle shows the highest level of membrane association, followed by the spherical particle with a similar radius, and the hexagonal prism-shaped particle, respectively. The free energy of membrane curvature calculated based on a membrane indentation induced by a particle association indicates that among the three particle shapes, the elongated spherical particle give the most stable membrane curvature. The elongated spherical particles show the highest cellular uptake into cytosol of human melanoma (A-375) and human liver carcinoma (HepG2) cells when observed through a confocal laser scanning fluorescence microscope. Quantitative study using flow cytometry also gives the same result. The elongated spherical particles also possess the highest cytotoxicity in A-375 and normal skin (WI-38) cell lines, comparing to the other two shaped particles.

Thermosensitive Hydrogel Co-loaded with Gold Nanoparticles and Doxorubicin for Effective Chemoradiotherapy.

Chemoradiotherapy, as a well-established paradigm to treat various cancers, still calls for novel strategies. Recently, gold nanoparticles (AuNPs) have been shown to play an important role as a radiosensitizer in cancer radiotherapy. The aim of this study was to evaluate the combination of polyethylene glycol (PEG) modified AuNPs and doxorubicin (DOX) to improve cancer chemoradiotherapy, in which the AuNPs was the radiosensitizer and the DOX was the model chemotherapeutic. A Pluronic® F127-based thermosensitive hydrogel (Au-DOX-Gel) loading AuNPs and DOX was developed by "cold method" for intratumoral injection. The formulation was optimized at a F127 concentration of 22% for Au-DOX-Gel. The release profiles compared to a control group were assessed in vitro and in vivo. Au-DOX-Gel showed sustained release of AuNPs and DOX. The cell viability and surviving fraction of mouse melanoma (B16) and Human hepatocellular liver carcinoma (HepG2) cells were significantly inhibited by the combination treatment of DOX and AuNPs under radiation. Tumor sizes of mice were significantly decreased by Au-DOX-Gel compared to controls. Interestingly, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and Ki-67 staining results showed that tumor cell growth and proliferation were inhibited by AuNPs combined with DOX under radiation, suggesting that the radiosensitization activity and combination effects might be caused by inhibition of tumor cell growth and proliferation. Furthermore, the results of skin safety tests, histological observation of organs, and the body weight changes indicated in vivo safety of Au-DOX-Gel. In conclusion, the Au-DOX-Gel developed in this study could represent a promising strategy for improved cancer chemoradiotherapy.

Polyamidoamine (PAMAM) dendrimers modified with short oligopeptides for early endosomal escape and enhanced gene delivery

Recently, non-viral vectors have become a popular research topic in the field of gene therapy. In this study, we conjugated short oligopeptides to polyamidoamine-generation 4 (PAMAM G4) to achieve higher transfection efficiency. Previous reports have shown that the PAMAM G4-histidine (H)-arginine (R) dendrimer enhances gene delivery by improving cell penetration and internalization mechanisms. Therefore, we synthesized PAMAM G4-H phenylalanine (F) R, PAMAM G4-FHR and PAMAM G4-FR derivatives to determine the best gene carrier with the lowest toxicity. Physicochemical studies were performed to determine mean diameters and surface charge of PAMAM derivatives/pDNA polyplexes. DNA condensation was confirmed using a gel retardation assay. Cytotoxicity and transfection efficiency were analyzed using human cervical carcinoma (HeLa) and human liver carcinoma (HepG2) cells. Similar levels of transfection were achieved in both cell lines by using gold standard transfection reagent PEI 25kD. Therefore, our results show that these carriers are promising and may help achieve higher transfection with negligible cytotoxicity.

Gold-Catalyzed Cycloisomerization and Diels-Alder Reaction of 1,4,9-Dienyne Esters to 3 a,6-Methanoisoindole Esters with Pro-Inflammatory Cytokine Antagonist Activity.

A synthetic method to prepare 3a,6-methanoisoindole esters efficiently by gold(I)-catalyzed tandem 1,2-acyloxy migration/Nazarov cyclization followed by Diels-Alder reaction of 1,4,9-dienyne esters is described. We also report the ability of one example to inhibit binding of tumor necrosis factor-α (TNF-α) to the tumor necrosis factor receptor 1 (TNFR1) site and TNF-α-induced nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation in cell at a half-maximal inhibitory concentration (IC50 ) value of 6.6 μM. Along with this is a study showing the isoindolyl derivative to exhibit low toxicity toward human hepatocellular liver carcinoma (HepG2) cells and its possible mode of activity based on molecular modeling analysis.

Synthesis of selenazolopyridine derivatives with capability to induce apoptosis in human breast carcinoma MCF-7 cells through scavenge of intracellular ROS

A series of selenazolopyridine derivatives have been synthesized and characterized by X-ray diffraction, high resolution NMR and Mass spectrum. The in vitro anticancer activities of the synthetic compounds were screened against a panel of human cancer cell lines, human breast carcinoma MCF-7 cells, human liver carcinoma HepG2 cells and L02 normal cell line by MTT assay. By analyzing the structure–activity relationship among the synthetic compounds, it was found that 2-(phenylamino) selenazolo [5,4-b] pyridine, (PSeD, 7) had higher growth inhibitory effect on MCF-7 cells. The intracellular mechanism of cell death was evaluated by flow cytometric analysis and ROS assay, which revealed that PSeD could induce MCF-7 cells apoptosis by scavenging intracellular ROS. Taken together, we regard PSeD as an antioxidant which could inhibit cancer cell growth through induction of apoptosis.

Cytotoxic, caspase-3 induction and in vivo hepatoprotective effects of phyllanthin, a major constituent of Phyllanthus niruri

The antiproliferative activity of phyllanthin (the major constituent in the decoction of Phyllanthus niruri L.) against human liver carcinoma HepG2 cells, the mechanism of cell death and the protective effect against carbon tetrachloride (CCl4)-induced hepatotoxicity in mice were investigated. Phyllanthin showed dose- and time-dependent growth inhibitions of HepG2 cells with the lowest EC50 value (10.16 ± 0.21 µg/ml) at 72 hours of treatment. Acute exposure to this compound exerted a significant caspase-3 expression that reached its peak after 8 hours of treatment (P < 0.001). Oral pre-treatment of phyllanthin at a dose of 120 mg/kg prior to CCl4-treatment effectively prevented the hepatic damage by reducing alanine aminotransferase (ALT) and aspartate aminotransferase (AST). These are the indications that phyllanthin is able to act independently to inhibit HepG2 cell proliferation via apoptotic cell death and to protect from hepatic injuries. Therefore, the effects of P. niruri extracts in the treatment of liver diseases can be related to the presence of phyllanthin.

Mechanical stress promotes cisplatin-induced hepatocellular carcinoma cell death.

Cisplatin (CisPt) is a commonly used platinum-based chemotherapeutic agent. Its efficacy is limited due to drug resistance and multiple side effects, thereby warranting a new approach to improving the pharmacological effect of CisPt. A newly developed mathematical hypothesis suggested that mechanical loading, when coupled with a chemotherapeutic drug such as CisPt and immune cells, would boost tumor cell death. The current study investigated the aforementioned mathematical hypothesis by exposing human hepatocellular liver carcinoma (HepG2) cells to CisPt, peripheral blood mononuclear cells, and mechanical stress individually and in combination. HepG2 cells were also treated with a mixture of CisPt and carnosine with and without mechanical stress to examine one possible mechanism employed by mechanical stress to enhance CisPt effects. Carnosine is a dipeptide that reportedly sequesters platinum-based drugs away from their pharmacological target-site. Mechanical stress was achieved using an orbital shaker that produced 300 rpm with a horizontal circular motion. Our results demonstrated that mechanical stress promoted CisPt-induced death of HepG2 cells (~35% more cell death). Moreover, results showed that CisPt-induced death was compromised when CisPt was left to mix with carnosine 24 hours preceding treatment. Mechanical stress, however, ameliorated cell death (20% more cell death).

Growth inhibition of human liver carcinoma HepG2 cells and α-glucosidase inhibitory activity of Murdannia bracteata (C.B. Clarke) Kuntze ex J.K. Morton extracts

Ethnopharmacological relevanceThe juice of the entire fresh herb and infusion of dried sample of Murdannia bracteata are consumed to treat liver cancer and diabetes in Malaysia. However, no scientific evidence of these bioactivities has been reported. Materials and methodsTo verify the therapeutic potentials of sequential extracts and infusion of this plant by determining its cytotoxicity against human liver carcinoma HepG2 cells and α-glucosidase inhibitory activity. The cytotoxic activities of the extracts against HepG2 were determined using a methylene blue assay, and an α-glucosidase inhibitory assay was used to assess anti-diabetic activity. The molecular basis of the anti-hepatocellular carcinoma activity of the most active extract was determined using RT-PCR. Chemical profiling of the most active extract was performed using GC–MS and UPLC analyses. ResultsThe results obtained from the cytotoxic screening revealed the dose-dependent growth inhibition of the HepG2 cells by only the hexane extract, with an EC50 value of 37.17±1.00µg/ml. The HepG2 cell death was found to be apoptotic in nature and based on the significant biphasic induction of caspase-3, suggesting that the extract inhibited cell growth through a caspase-3-dependent pathway. The hexane extract also displayed α-glucosidase inhibitory activity, with an EC50 of 117.04±2.34µg/ml. GC–MS analysis revealed that α-tocopherol was the major volatile compound in the hexane extract, and two phenolics (apigenin and caffeic acid derivatives) were detected using UPLC. ConclusionsBased on various published reports, it could be suggested that α-tocopherol and apigenin derivatives might be involved in the apoptosis-based cytotoxicity of the active extract of this plant against HepG2 carcinoma cells. The effects of this plant in the treatment of diabetes can be related to the presence of α-glucosidase inhibitors, such as the caffeic acid derivative identified in the active extract.

Glycosaminoglycan-targeted iron oxide nanoparticles for magnetic resonance imaging of liver carcinoma

To develop an efficient probe for targeted magnetic resonance (MR) imaging of liver carcinoma, the surface modification of superparamagnetic iron oxide nanoparticles (SPIONs) was carried out by conjugating a naturally-occurring glycosaminoglycan with specific biological recognition to human hepatocellular liver carcinoma (HepG2) cells. These modified SPIOs have good water dispersibility, superparamagnetic property, cytocompatibility and high magnetic relaxivity for MR imaging. When incubated with HepG2 cells, they demonstrated significant cellular uptake and specific accumulation, as confirmed by Prussian blue staining and confocal microscopy. The in vitro MR imaging of HepG2 cells and in vivo MR imaging of HepG2 tumors confirmed their effectiveness for targeted MR imaging of liver carcinoma.

Mixed-ligand copper(II) phenolate complexes: Synthesis, spectral characterization, phosphate-hydrolysis, antioxidant, DNA interaction and cytotoxic studies

A series of phenol-based mixed-ligand copper(II) complexes of the type [CuL1–4(diimine)] (1–8), where L1–4=N1,N2-bis(5-substituted-2-hydroxybenzylidene)-1,2-ethylene/phenylenediimine and diimine=2,2′-bipyridyl (bpy) or 1,10-phenanthroline (phen), have been isolated and fully characterized by analytical and spectral techniques. Electronic spectra of complexes suggest Cu(II) cation has a d9 electronic configuration, adopting distorted octahedral geometry with axial elongation, due to Jahn–Teller effect. Electrochemical studies of complexes evidenced one-electron irreversible reduction wave in the cathodic region. The observed rate constant (k) values for the hydrolysis of 4-nitrophenylphosphate (4-NPP) are in the range of 0.25–3.82×10−2min−1. The obtained room temperature magnetic moment values (1.79–1.90BM) lies within the range observed for octahedral copper(II) complexes. Antioxidant studies revealed that these complexes possess considerable radical scavenging potency against DPPH. The binding studies of complexes with calf thymus DNA (CT-DNA) revealed intercalation with minor-groove binding, and the complex 4 exhibits highest binding activity than the other complexes. The cleavage activity on supercoiled pBR322 DNA revealed the involvement of hydroxyl radical and singlet-oxygen as reactive oxygen species, and complexes encourage binding to minor-groove. Further, the cytotoxicity of complex 4 on human hepatocellular liver carcinoma HepG2 cell line implies the cell death through apoptosis.

Synthesis and antiproliferative activity of some new thieno[2,3-d]pyrimidin-4(3H)-ones containing 1,2,4-triazole and 1,3,4-thiadiazole moiety

Some new thieno[2,3-d]pyrimidin-4(3H)-ones containing 1,2,4-triazole and 1,3,4-thiadiazole moiety were synthesized using thieno[2,3-d]pyrimidin-3(4H)-yl)acetohydrazides as precursors in order to determine their cytotoxicity. Compounds 5, 7–8 and 10–18 were evaluated for their cytotoxical effect on four cancer cell lines: human colorectal cancer cell line HT-29, breast cancer cells MDA-MB-231, cervical cancer cells HeLa, human liver carcinoma HepG2 and human normal diploid cell line Lep3. Exclusively high cytotoxic activity of compounds 8, 16 and 17 against MDA-MB-231 cells was ascertained and the calculated IC50 values were 3.91·10−2, 1.2·10−3 and 3.74·10−2 μM respectively. Thienopyrimidinones 10, 15 and 17 exhibited high cytotoxicity against HT-29 cell and the IC50 values were in the range 1.56·10−3 μM– 0.13 μM. To HeLa cell lines cytotoxicity demonstrated compounds 8, 10, 11, 13 and 15–18 but the substance 13 was the most toxic with IC50 – 9.5·10−4 μM. Distinctly high antiproliferative activity of derivatives 10, 14–15 and 17–18 was estimated against Hep G2, compound 15 showed IC50 – 0.21 μM. Proliferative effects to Lep 3 demonstrated compounds 5, 7–8, 11–14, 16, 18 whose EC50 values were from 0.12 to 2.21 μM. The biological data highlighted that the nature and the position of the substituents influence both the cytotoxicity to the cancer cells and the proliferation properties to Lep3 of the tested compounds.

A small molecule peptidomimetic that binds to c-KIT1 G-quadruplex and exhibits antiproliferative properties in cancer cells

A modular synthesis of l-proline derived peptidomimetics has been developed using the CuI catalyzed Huisgen cycloaddition between an azido prolinamide with pyridine and benzene dicarboxamide containing dialkynes. Förster Resonance Energy Transfer (FRET) melting assay provided an initial indication that the pyridyl analogue can stabilize the c-KIT1 quadruplex DNA. A competitive FRET-melting assay and Fluorescent Intercalator Displacement (FID) assay suggest that the pyridyl ligand shows excellent selectivity for c-KIT1 quadruplex over duplex DNA and other investigated G-quadruplexes. Molecular docking studies indicate that the pyridyl ligand can adopt unique conformations upon binding to c-KIT1 quadruplex due to the presence of intramolecular hydrogen bonds. The pyridyl ligand can perturb cell cycle progression and induce necrotic cell death of human hepatocellular liver carcinoma HepG2 cells.

Synthesis of novel lipophilic N-substituted norcantharimide derivatives and evaluation of their anticancer activities.

This research attempted to study the effect of lipophilicity on the anticancer activity of N-substituted norcantharimide derivatives. Twenty-three compounds were synthesized and their cytotoxicities against five human cancer cell lines studied. The lipophilicity of each derivative was altered by its substituent, an alkyl, alkyloxy, terpenyl or terpenyloxy group at the N-position of norcantharimide. Further, among all synthesized derivatives studied, the compounds N-farnesyloxy-7-oxabicyclo[2.2.1]heptane-2,3-dicarboximide (9), and N-farnesyl-7-oxabicyclo[2.2.1]heptane-2,3-dicarboximide (18), have shown the highest cytotoxicity, anti-proliferative and apoptotic effect against human liver carcinoma HepG2 cell lines, yet displayed no significant cytotoxic effect on normal murine embryonic liver BNL CL.2 cells. Their overall performance led us to believe that these two compounds might be potential candidates for anticancer drugs development.

Effects of Annurca apple polyphenols on lipid metabolism in HepG2 cell lines: A source of nutraceuticals potentially indicated for the metabolic syndrome

The influence of polyphenolic extracts from Annurca apple peel and flesh on lipid metabolism in human hepatocellular liver carcinoma (HepG2) cell lines was evaluated, and compared with those of other conventional cultivars, such as Red Delicious (RD), Pink Lady (PL), Fuji (F) and Golden Delicious (GD). Annurca flesh revealed the best inhibition capacity against lipase activity, and triglyceride levels in the cell medium increased by almost 20 times above control levels. Incubation with Annurca flesh polyphenols enhanced low-density lipoproteins (LDL) receptor binding activity by 40% and led to an increase in Apolipoprotein A1 (ApoA1) cell expression of 33.3% above control levels. Experimental data would indicate for Annurca flesh polyphenols a significant hypolipidemic potential in comparison with other more common apple cultivars, thus leading to hypothesise a helpful role in the prevention and care of diseases in subjects affected by metabolic syndrome and to propose the possibility of formulating therapeutically useful nutraceutical products. Undoubtedly, further in vivo and clinical studies are needed to confirm such healthy effects through diet.

Evaluation of 147 Kampo prescriptions as novel protein tyrosine phosphatase 1B (PTP1B) inhibitory agents

BackgroundProtein tyrosine phosphatase (PTP) 1B, a negative regulator of the insulin and leptin signaling pathways, is currently considered a promising target for the development of novel therapeutic approaches used to treat insulin-resistant type 2 diabetes mellitus (IR-T2DM). In this study, we examined the PTP1B inhibitory activity of 147 Japanese prescription Kampo formulations to evaluate their potential for clinical application in IR-T2DM treatment.MethodsWe specifically defined the prescribed daily dose as 1 Unit (U), and 147 Japanese prescription Kampo formulations were screened for PTP1B inhibitory activity at a final concentration of 0.1 mU/mL. We investigated the dependence of the inhibitory activity on the concentration of the Kampo formulations that exhibited high PTP1B inhibitory activity. Their inhibition mode by kinetic analysis, inhibitory selectivities against four homologous PTPs (TCPTP, VHR, SHP-1 and SHP-2) and cellular activity in the insulin-signaling pathway by increasing the insulin-stimulated Akt phosphorylation level in human hepatocellular liver carcinoma HepG2 cells, were also investigated. The statistical partial least squares regression method was used to identify the crude drugs with the greatest contribution to the PTP1B inhibitory activity of the Kampo formulations.ResultsDaiokanzoto, Masiningan, Tokakujokito, Keimakakuhanto and Choijokito exhibited high PTP1B inhibitory activity, which was concentration-dependent. Daiokanzoto, Masiningan and Tokakujokito inhibited PTP1B by mixed inhibition modes and exhibited different inhibitory selectivities against four homologous PTPs. Masiningan also exhibited cellular activity. Statistical analyses indicated that the constituent crude drug Rhei Rhizoma provided the greatest contribution to the PTP1B inhibitory activity of these Kampo formulations.ConclusionsHigh PTP1B inhibitory activity was predominantly associated with formulations that were classified as Jyokito in Kampo medicine and with a modern clinical indication of constipation. Currently, there is no clinical treatment for IR-T2DM that uses a mechanism of action based on PTP1B inhibition. Thus, we propose the Kampo formulations identified in this study as strong PTP1B inhibitors, which could be developed as clinical therapeutic agents to treat IR-T2DM.