Human Hepatocellular Cell Line Research Articles

Selective apoptotic and genotoxic effects of pomegranate peel extract against human hepatocellular carcinoma HepG2 cell line

Selective apoptotic and genotoxic effects of pomegranate peel extract against human hepatocellular carcinoma HepG2 cell line

A multi-omics dataset of human transcriptome and proteome stable reference

The development of high-throughput omics technology has greatly promoted the development of biomedicine. However, the poor reproducibility of omics techniques limits their application. It is necessary to use standard reference materials of complex RNAs or proteins to test and calibrate the accuracy and reproducibility of omics workflows. The transcriptome and proteome of most cell lines shift during culturing, which limits their applicability as standard samples. In this study, we demonstrated that the human hepatocellular cell line MHCC97H has a very stable transcriptome (r = 0.983~0.997) and proteome (r = 0.966~0.988 for data-dependent acquisition, r = 0.970~0.994 for data-independent acquisition) after 9 subculturing generations, which allows this steady standard sample to be consistently produced on an industrial scale in long term. Moreover, this stability was maintained across labs and platforms. In sum, our study provides omics standard reference material and reference datasets for transcriptomic and proteomics research. This helps to further standardize the workflow and data quality of omics techniques and thus promotes the application of omics technology in precision medicine.

Small-molecular cyclic peptide exerts viability suppression effects on HepG2 cells via triggering p53 apoptotic pathways

Cyclic peptides have become an attractive modality for drug development due to their high specificity, metabolic stability and higher cell permeability. In an effort to explore novel antitumor compounds based on natural cyclopeptide from the phakellistatin family, we found an isoindolinone-containing analog (S-PK6) of phakellistatin 6 capable of suppressing the viability and proliferation of HepG2 cells. The aim of the present study is to shed light on the mechanism of action of this novel compound. We have detected differences in gene expression before and after treatment with S-PK6 in human hepatocellular carcinoma HepG2 cell line by transcriptome sequencing. To further investigate biological effects, we have also extensively investigated the tumor cell cycle, mitochondrial membrane potential, and intracellular Ca2+ concentration after S-PK6 treatment. Based on the finding that the apoptosis was associated with the p53 signaling pathway and MAPK signaling pathway, western blotting tests were used to assess the expression level of p53 protein and its degenerative regulator MDM2 protein, which showed that S-PK6 could increase p53 levels efficiently. In summary, our results demonstrate the mechanism of action of a small-molecule cyclopeptide, which could be very useful for examining of the possible mechanisms of natural cyclopeptides.

Phenelzine protects against acetaminophen induced apoptosis in HepG2 cells

Acetaminophen (APAP) overdosing is the most common cause of drug-induced liver failure. Despite extensive study, N-acetylcysteine is currently the only antidote utilized for treatment. The purpose of this study was to evaluate the effect and mechanisms of phenelzine, an FDA-approved antidepressant, on APAP-induced toxicity in HepG2 cells. The human liver hepatocellular cell line HepG2 was used to investigate APAP-induced cytotoxicity. The protective effects of phenelzine were determined by examining the cell viability, combination index calculation, Caspase 3/7 activation, Cytochrome c release, H2O2 levels, NO levels, GSH activity, PERK protein levels, and pathway enrichment analysis. Elevated H2O2 production and decreased glutathione (GSH) levels were indicators of APAP-induced oxidative stress. The combination index of 2.04 indicated that phenelzine had an antagonistic effect on APAP-induced toxicity. When compared to APAP alone, phenelzine treatment considerably reduced caspase 3/7 activation, cytochrome c release, and H2O2 generation. However, phenelzine had minimal effect on NO and GSH levels and did not alleviate ER stress. Pathway enrichment analysis revealed a potential connection between APAP toxicity and phenelzine metabolism. These findings suggested that phenelzine’s protective effect against APAP-induced cytotoxicity could be attributed to the drug’s capacity to reduce APAP-mediated apoptotic signaling.

Identification of human in vitro metabolites of the haemoglobin S polymerization inhibitor voxelotor for doping control purposes.

Voxelotor (GBT440) is a haemoglobin S polymerization inhibitor used to treat anaemia in sickle cell disease. Due to an increase of arterial oxygen saturation as well as serum erythropoietin and haemoglobin, the World Anti-Doping Agency included voxelotor in the list of prohibited substances and methods in 2023. The objective of the present study was to identify and characterize metabolites of voxelotor to detect a potential misuse by athletes. The biotransformation was studied in vitro using the human hepatocellular cell line HepG2 and pooled human liver microsomes. The metabolites were analysed using high-performance liquid chromatography (high-resolution) mass spectrometry. In total, three phase I metabolites and six phase II metabolites (resulting from glucuro-conjugation and O-methylation) were formed by the HepG2 cells in a time-dependent manner, and two phase I metabolites were generated by the liver microsomes, among them one also found in the HepG2 incubations. A reduced metabolite and the glucuro-conjugate of a reduced metabolite were the most abundant formed by HepG2 cells. In addition, metabolites resulting from mono-hydroxylation, reduction and O-methylation in different combinations were identified. Voxelotor was also found as glucuro-conjugate with a low abundance. With the spectrometric behaviour of voxelotor and its in vitro metabolites described herein, an implementation in doping control screening and, consequently, a detection of an abuse in an athlete urine sample might be possible.

Investigation of the toxicity of a glyphosate-based herbicide in a human liver cell line: Assessing the involvement of Nrf2 pathway and protective effects of vitamin E and α-lipoic acid

Glyphosate-based herbicides (GBHs) are the most widely used herbicides all over the world and has gained more attention in recent years because of health safety concerns. In this study, Roundup, one of the most popular glyphosate formulations, was used to evaluate cytotoxic, oxidative stress and apoptosis inducing effects of GBHs in a human hepatocellular cell line (HepG2). Roundup was shown to significantly increase cellular reactive oxygen species (ROS) levels, which lead to activation of the nuclear factor-erythroid-2-related factor 2 (Nrf2) antioxidant defense pathway including reduced levels of heme oxygenase 1 (HO-1). Furthermore, Roundup was found to induce apoptosis and further analysis confirmed involvement of a mitochondrial-dependent pathway verified by increased Bax/Bcl-2 ratios. Investigation of the protective effects of antioxidants vitamin E (Vit E) and α-lipoic acid (LA) against Roundup toxicity showed that both antioxidants significantly reduced the cytotoxicity, ROS formation, HO-1 downregulation, and apoptosis and that Vit E did so more efficiently than LA. In conclusion, our findings highlight the ROS producing and apoptosis inducing effects associated with GBHs, the activation of Nrf2 pathway as a defense mechanism and the protective effects of Vit E and LA against GBH toxicity.

“Disruption of the molecular clock severely affects lipid metabolism in a hepatocellular carcinoma cell model”

Involved in triglyceride (TG) and glycerophospholipid metabolism, the liver plays a crucial physiological role in the human body both as a major metabolic integrator and a central hub for lipid and energy homeostasis. Metabolic disorders can be caused by various factors that promote abnormal lipid accumulation in storage organelles called lipid droplets (LDs), as in hepatic steatosis, a metabolic syndrome manifestation that can progress to a hepatocellular carcinoma, the most common primary liver malignancy worldwide. Modern life involves conditions that disrupt the biological clock, causing metabolic disorders and higher cancer risk. A circadian clock is present in the liver and in immortalized cell lines and temporally regulates physiological processes by driving transcriptional and metabolic rhythms. Here we investigated metabolic rhythms in HepG2 cells, a human hepatocellular carcinoma-derived cell line, and the link between these rhythms and the circadian clock in control (Bmal1-wildtype) and Bmal1-disrupted (B-D) cells having their molecular clock impaired. Rhythms in the expression of lipid-synthesizing enzymes ChoKα, Pcyt2, and Lipin1, in the metabolism of particular glycerophospholipids such as phosphatidylcholine (PC) and phosphatidylethanolamine, and in the phosphatidylcholine/phosphatidylethanolamine ratio and TG and LD content were observed in Bmal1-wildtype cells. By contrast, in the B-D model, the whole hepatic metabolism was severely altered with a significant reduction in the TG and LD content as well as in ChoKα and other related lipid enzymes. Together, our results suggest a very strong crosstalk between the molecular clock and lipid metabolism, which exhibits an exacerbated pathological condition in B-D cells.

Cytotoxic cycloartane triterpenoid saponins from Actaea vaginata and their mechanism of action

A further phytochemical investigation of the whole plants of Actaea vaginata afforded two new cycloartane triterpenoid saponins, (20S*,24R*)-15α,16β-diacetoxy-20,24-epoxy-9,19-cyclolanostane-3β,25-diol-3-O-β-d-xylopyranoside (1) and (20S)-15β,16β -diacetoxy-18,20-epoxy-3β,25-diol-24-oxo-9,19-cyclolanostan-3-O-β-D-xylo-pyrano-syl-25-O-β-d-glucopyranoside (2), together with four known compounds (3–6). Their structures were established on the basis of extensive analysis of NMR and HRESIMS data as well as by comparison with the reported data in the literature. All the isolates were evaluated for their cytotoxic activities against human hepatocellular carcinoma HepG2 cell line. Compounds 1 and 2 exhibited weak cytotoxicity with IC50 values of 36.10 and 27.39 μM, respectively. In addition, beesioside I (6) was found to significantly inhibit proliferation and induce apoptosis in HepG2 cells. A closer examination of underlying mechanism revealed that beesioside I could increase the levels of ROS and caspase-3 and promote phosphorylation of JNK in the JNK signaling pathway. Molecular modeling studies also shed further light on how beesioside I interacted with the key protein kinase.

The Efficacy of Combined Therapy of Regorafenib with Detoxicating and Stasis Softening Chinese Herbal Spleen Tonics in Mid-/Late-Stage Hepatocellular Carcinoma.

Objective To explore the efficacy of combined therapy of Regorafenib with detoxicating and stasis softening Chinese herbal spleen tonics (DSS-splenic tonics) in mid-/late-stage hepatocellular carcinoma. Methods Retrospective observational data of 120 patients were obtained, 60 of which received combined therapy of DSS-splenic tonics and regorafenib. Adverse event, overall survival (OS), and time-to-progress (TTP) were analyzed. Synergistic effect of DSS-spleen tonics was found and validated in human hepatocellular carcinoma HCCLM3 cell line and xenograft mouse models. Results Combination of regorafenib and DSS-splenic tonics also slightly extended the TTP and OS compared with treatment of regorafenib alone, suggesting DSS-splenic tonics has synergistic effect with regorafenib. Both Regorafenib and DSS-spleen tonics exerted inhibitory effect on cell viability and invasion capability of HCCLM3 cells, and combining both could enhance the antitumor effect. At molecular level, we found that VEGF, HIF-1α, MVD, and VEGF2 were all suppressed by regorafenib and DSS-splenic tonics. These results suggest that DSS-spleen tonics function synergistically with regorafenib in HCC by enhancing the regulation of regorafenib on VEGF, MMP-2, HIF-1α, and MVD, and may diminish angiogenesis during HCC progression. Conclusion DSS-spleen tonics could exert synergistic antitumor effect with regorafenib via targeting VEGF.

In vitro antioxidant and cytotoxicity activities of selected indigenous South African medicinal plants

Background: Medicinal plants are regarded as a large source of phytochemicals that may have anticancer properties. This could lead to the development of innovative drugs or alternative therapy against cancer.
 Objective: This study was designed to determine the antioxidant and cytotoxicity effect of 5 selected indigenous South African medicinal plants namely; Bulbine frutescens, Bulbine natalensis, Chlorophytum comosum, Kniphofia uvaria, and Tulbaghia violacea.
 Method: Phytochemical extracts namely; methanol, 50%, 100% ethanol, and water extracts were prepared from the root and shoot of the plants. The antioxidant effect of methanol extracts of the plant materials was performed using a DPPH assay. A preliminary cytotoxicity screening of the phytochemical extracts in the human colon (Caco-2), cervical (HeLa), and hepatocellular (HepG2) cell lines were determined followed by the half-maximal inhibitory concentration (IC50) using MTT assay.
 Result: The methanol root extract of B. natalensis and B. frutescens (33.20% and 26.33% respectively) and shoot extract of K. uvaria (17.10%) showed the highest antioxidant. Out of the 5 plants, only 100% ethanol extract of C. comosum, K. uvaria, and T. violacea caused more than 80% cytotoxicity in HepG2 and Caco-2 cell lines. The shoot of B. frutescens (10.43 μg/ml), K. uvaria (23.0 μg/ml), and root of C. comosum (23.77 μg/ml) were the most active with the highest cytotoxicity.
 Conclusion: C. comosum, K. uvaria, and T. violacea possess significant cytotoxicity that is promising in developing alternative drugs against colon and liver cancers. Our results provided new pieces of evidence for antioxidant and cytotoxic activities of these plants which could be useful for developing new anticancer therapies.
 Keywords: In vitro antioxidant; cytotoxicity activities; South African medicinal plants; C. comosum, K. uvaria, T. violacea.

Semisynthesis and biological evaluation of (+)-sclerotiorin derivatives as antitumor agents for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma is one of the most common primary hepatic malignancy. Herein, a series of semisynthesized derivatives (2–30) of the natural product (+)-sclerotiorin (1) was prepared and evaluated the cytotoxic activities against six cancer cell lines. Among them, 3 and 5 were the most effective compounds against human hepatocellular carcinoma Bel-7402 cell line with IC50 values of 1.45 and 1.15 μM, respectively. Molecular mechanism study showed that 5 disrupted the mitochondrial membrane potential and induced apoptosis in a caspase-dependent manner. In addition, 5 affected AKT and ERK signaling pathways and induced AKT and ERK proteins degradation through ubiquitin-proteasome system. Furthermore, 5 displayed significant in vivo anticancer effects in the xenograft models with decreasing the tumor mass by 52.5%. The safety evaluation was confirmed by acute toxicity subchronic toxicity tests, paraffin sections of mice organ and blood routine examination. Taken together, 5 can be developed as a potential therapeutic agent for hepatocellular carcinoma.

Anticancer property of Selaginella bryopteris (L.) Bak. against hepatocellular carcinoma in vitro and in vivo

BackgroundHepatocellular carcinoma (HCC) is the most common and leading cause of cancer-related mortality worldwide. It has limited therapeutic options and side effects caused by current treatment methods. Selaginella bryopteris is used traditionally in the treatment of several health-related problems but mostly remains to be scientific validation. PurposeThis study investigated the effect of Selaginella bryopteris on a hepatic cancer cell line in vitro and in the NDEA-induced HCC rat model in vivo. MethodThe anticancer effect of S. bryopteris was evaluated in vitro using a human hepatocellular carcinoma HepG2 cell line. Gas chromatography-mass spectrometry (GC–MS) was carried out to analyze the phytoconstituents of S. bryopteris extract. Different techniques were used in this in vitro anticancer study to evaluate cell viability, alteration in nuclear morphology, mitochondrial membrane potential, and generation of reactive oxygen species (ROS). For an in vivo study, Sprague Dawley (SD) rats were induced with N- nitrosodiethylamine (200 mg/kg b.w. once, i.p.) and carbon tetrachloride (3 mL/kg/week b.w., s.c.) up to six weeks. The induced animals were treated with S. bryopteris extract (100 and 200 mg/kg) and silymarin (100 mg/kg) for 28 days. The level of liver function parameters and antioxidant enzymes were assessed. A reverse transcriptase-polymerase chain reaction was used to evaluate the gene expression patterns of p53, Bax, caspase-3, caspase-9, and Bcl-2 mRNAs. ResultsIn a liver cancer cell line (HepG2), Selaginella bryopteris extract (SBE) induced apoptosis through altering mitochondrial membrane potential, nuclear condensation, and the production of reactive oxygen species. The elevated level of ALT, AST, GGT, and TBL in HCC-induced rats were declined significantly by SBE administration. SBE enhanced antioxidant activity (GST, Catalase, SOD, GPX), antioxidant molecule (GSH), and reduced the level of stress marker (MDA) in NDEA induced animals. The effects of SBE against HCC were also demonstrated by the up-regulated expression of pro-apoptotic genes (p53, caspase-3, caspase-9, Bax) and the down-regulated expression of anti-apoptotic (Bcl-2) gene by qRT-PCR analysis in liver tissue. Histological analysis revealed that the extract improved the liver architecture. The major bioactive compounds detected by GC–MS analysis were imidazole, amentoflavone, gallic acid, catechine, palmitic acid, lupeol, l-Fucitol, and myo-inositol. SBE was found to be safe in an acute toxicity test. As a result, our findings indicate that S. bryopteris extract may have anti-HCC potential. ConclusionsIn vitro and in vivo, Selaginella bryopteris extract has significant antiproliferative action against HCC. S. bryopteris extract can be used as a safe and natural potential drug candidate against hepatocellular carcinoma.

Cytotoxicity and apoptosis response of hexagonal zinc oxide nanorods against human hepatocellular liver carcinoma cell line

Hexagonal zinc oxide nanorods (ZnO-NRs) were prepared via solution process using zinc nitrate hexahydrate (Zn(NO3)2·6H2O, 0.25 M), hexamethylenetetramine (HMT) and sodium hydroxide at low concentration (4 × 10-3 M in 100 ml of distilled water) and refluxed at 100 °C for an hour. The HMT was used because its act as a template for the nucleation and growth of zinc oxide nanorods. The X-ray diffraction patterns (XRD) clearly reveal that the grown product is pure zinc oxide. The diameters and lengths of the synthesized nanorods lie between 200 and 250 nm and 2–3 μm respectively as observed from the field emission scanning electron microscopy (FESEM). The chemical functional properties was analyzed by Fourier Transform infra-red (FTIR) spectroscopy. This study was designed to show the possible effect of ZnO-NRs in human liver cancer (HepG2) cells. It induces cytotoxicity via reactive oxygen species (ROS), mitochondrial membrane potential. For gene expression analysis, it induces apoptotic gene marker P53, Bax, caspase3, Bcl2 genes. Based on analysis and observations, it concludes that the ZnO-NRs were utilized for toxicity at dose dependent via ROS generation against human hepato cellular liver carcinoma cell line.

Effect of 5'-fluoro-2'-deoxycytidine and sodium butyrate on the genes of the intrinsic apoptotic pathway, p21, p53, cell viability, and apoptosis in human hepatocellular carcinoma cell lines

Backgrounds: Epigenetic regulation such as DNA methylation plays a major role in chromatin organization and gene transcription. Additionally, histone modification is an epigenetic regulator of chromatin structure and influences chromatin organization and gene expression. The relationship between DNA methyltransferase (DNMTs) expression and promoter methylation of the tumor suppressor genes (TSGs) has been reported in various cancers. Previously, the effect of 5-aza-2'-deoxycytidine (5-AZA-CdR), trichostatin A (TSA), and valproic acid (VPA) was shown on various cancers. This study aimed to investigate the effect of 5'-fluoro-2'-deoxycytidine (FdCyd) and sodium butyrate on the genes of the intrinsic apoptotic pathway, p21, p53, cell viability, and apoptosis in human hepatocellular carcinoma SNU449, SNU475, and SNU368 cell lines. 
 Materials and Methods: In this lab trial study, the SNU449, SNU475, and SNU368 cells were cultured and treated with 5'-fluoro-2'-deoxycytidine and sodium butyrate. To determine cell viability, cell apoptosis, and the relative gene expression level, MTT assay, flow cytometry assay, and qRT-PCR were done respectively.
 Results: 5'-fluoro-2'-deoxycytidine and sodium butyrate changed the expression level of the BAX, BAK, APAF1, Bcl-2, Bcl-xL, p21, and p53 gene (P<0.0001) by which induced cell apoptosis and inhibit cell growth in all three cell lines, SNU449, SNU475, and SNU368. 
 Conclusion: Both compounds played their roles through the intrinsic apoptotic pathway to induce cell apoptosis.

Iso-suillin-induced DNA damage leading to cell cycle arrest and apoptosis arised from p53 phosphorylation in A549 cells

Extensive investigations have revealed that iso-suillin, a secondary metabolite isolated from Suillus flavus, could induce cell cycle arrest and apoptosis in human chronic myeloid leukemia K562 cells, human hepatocellular carcinoma SMMC-7721 cell line, and human small cell lung cancer H446 cell line in vitro.In the present study, human lung cancer A549 cells were used to reveal the mechanism of iso-suillin's effects on lung adenocarcinoma, which were detected both in vitro and in vivo.Results showed that iso-suillin potently inhibited A549 cell proliferation through an early G1 arrest. Iso-suillin also induced A549 cell apoptosis in vitro. Phosphorylation of p53 at serines 15 and 20 may be one of the pivotal factors for cell cycle arrest and apoptosis after treatment of iso-suillin in A549 cells.Moreover, in an A549 xenograft model, tumor growth and progression could be inhibited by iso-suillin. Body weight change and some vital organs toxicity was also roughly examined, no significant toxic effects of iso-suillin were shown (at a dose of 5 mg/kg for each administration).The in vitro and in vivo anti-tumor effects implied that iso-suillin may act as a tumor growth inhibitor, and its induction of p53 phosphorylation is pivotal for cell cycle arrest and apoptosis in A549 cells.

Engineered adeno-associated virus 3 vector with reduced reactivity to serum antibodies

The natural serotypes of adeno-associated virus (AAV) or their variants, such as AAV8 and AAV5, are commonly used as vectors in the clinical programs for liver-targeted gene therapy. While AAV8 vectors are not highly efficient at targeting primary human hepatocytes, AAV3 vectors have recently demonstrated remarkable efficiency at targeting both human and non-human primate hepatocytes. However, the presence of high levels of neutralizing antibodies (NAbs) impedes transduction into hepatocytes, representing a major obstacle to the clinical application of AAV3 vectors. Herein, we engineered the viral capsid to reduce its reactivity with pre-existing NAbs, thereby enhancing the transduction efficiency. By introducing three substitutions (S472A, S587A, and N706A) on the surface loop of AAV3B capsid protein, we generated a triple mutant AAV3 (AAV.GT5) vector with less reactivity to anti-AAV capsid NAbs. While the transduction efficiency of AAV.GT5 into human hepatocellular cell lines was similar to those of parental AAV3B, it was 50-fold higher for hepatocytes derived from humanized mice compared to AAV8 vectors. Moreover, the AAV.GT5 vector yield was similar to those of the AAV2 and AAV3B vectors. Thus, high resistance to pre-existing NAbs makes AAV.GT5 a promising candidate for future liver-targeted gene therapy clinical trials.

Functional roles of GRP78 in hepatitis B virus infectivity and antigen secretion.

Viruses utilize cellular proteins to mediate their life cycle. However, the hepatitis B virus (HBV) life cycle is still mysterious and remains to be elucidated. Here, GRP78/BiP/HSPA5, a 78 kDa glucose-regulated protein, was identified as a preS2 interacting protein. Pulldown assay showed the interaction of glucose-regulated protein 78 (GRP78) with both the preS2 domain-containing large S and middle S proteins expressed in a human hepatocellular cell line. The immunofluorescence studies revealed that the preS2 colocalized with GRP78. Interestingly, it was found that preS2 specifically bound to the ATPase domain of GRP78. To understand how GRP78 plays a role in HBV infection, stably GRP78-expressing cells were established, which promoted HBV infectivity and replication. In contrast, knockdown of GRP78 changed the HBV antigen secretion but not the viral DNA amplification. Taken together, these results suggest that GRP78 should interact with preS2 via the ATPase domain and modulate both the HBV infectivity and HBV antigen secretion.

Cytotoxic and Genotoxic Effects of Cyanobacterial and Algal Extracts-Microcystin and Retinoic Acid Content.

In the last decade, it has become evident that complex mixtures of cyanobacterial bioactive substances, simultaneously present in blooms, often exert adverse effects that are different from those of pure cyanotoxins, and awareness has been raised on the importance of studying complex mixtures and chemical interactions. We aimed to investigate cytotoxic and genotoxic effects of complex extracts from laboratory cultures of cyanobacterial species from different orders (Cylindrospermopsis raciborskii, Aphanizomenon gracile, Microcystis aeruginosa, M. viridis, M. ichtyoblabe, Planktothrix agardhii, Limnothrix redekei) and algae (Desmodesmus quadricauda), and examine possible relationships between the observed effects and toxin and retinoic acid (RA) content in the extracts. The cytotoxic and genotoxic effects of the extracts were studied in the human hepatocellular carcinoma HepG2 cell line, using the MTT assay, and the comet and cytokinesis-block micronucleus (cytome) assays, respectively. Liquid chromatography electrospray ionization mass spectrometry (LC/ESI-MS) was used to detect toxins (microcystins (MC-LR, MC-RR, MC-YR) and cylindrospermopsin) and RAs (ATRA and 9cis-RA) in the extracts. Six out of eight extracts were cytotoxic (0.04–2 mgDM/mL), and five induced DNA strand breaks at non-cytotoxic concentrations (0.2–2 mgDM/mL). The extracts with genotoxic activity also had the highest content of RAs and there was a linear association between RA content and genotoxicity, indicating their possible involvement; however further research is needed to identify and confirm the compounds involved and to elucidate possible genotoxic effects of RAs.

Virucidal activity of oriental hornet Vespa orientalis venom against hepatitis C virus.

BackgroundHepatitis C virus (HCV) infection is a major worldwide health problem that can cause liver fibrosis and hepatocellular carcinoma (HCC). The clinical treatment of HCV infection mainly relies on the use of direct-acting antivirals (DAAs) that are usually expensive and have side effects. Therefore, achieving the discovery of more successful agents is always urgent. In this context, antiviral compounds that inhibit viral infections and disease progression with important therapeutic activities have been identified in animal venoms including arthropod toxins. This indicates that arthropod venoms represent a good natural source of promising candidates for new antivirals. MethodsThe antiviral activity of the wasp venom (WV), isolated from the Oriental hornet (Vespa orientalis), was assessed using cell culture technique with human hepatocellular carcinoma-derived cell line (Huh7it-1) and the recombinant strain of HCV genotype 2a (JFH1). ResultsThe results revealed that WV inhibited HCV infectivity with 50% inhibitory concentration (IC50) of 10 ng/mL, while the 50% cytotoxic concentration (CC50) was 11,000 ng/mL. Time of addition experiment showed that the WV blocked HCV attachment/entry to the cells probably through virucidal effect. On the other hand, the venom showed no inhibitory effect on HCV replication. ConclusionWV can inhibit the entry stage of HCV infection at non-cytotoxic concentrations. Therefore, it could be considered a potential candidate for characterization of natural anti-HCV agents targeting the entry step.

Phytochemical Biological and Cytotoxic Activities of Calothamnus quadrifidus Leaves Cultivated in Egypt

The hydro distilled essential oil obtained from Calothamnus quadrifidus leaves was analyzed by gas liquid chromatography-mass spectroscopy. Quantification of the oil constituents was carried out using the gas liquid chromatography-flame ionization detection device where 1,8-cineole was quantified as 525.62 μg/ml. The oil showed potential antioxidant activity when tested by 1,1-diphenyl-2-picrylhydrazine radical scavenging assay where the concentration required to scavenge 1,1-diphenyl-2-picrylhydrazine by 50 %=37.3 μg. The cytotoxic activity of the essential oil was evaluated using 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide assay compared with 1,8-cineole and doxorubicin. Calothamnus quadrifidus leaves essential oil cytotoxic activity was significant against human lung cell line A-549 (2.37 μg), human colon cell line HCT-116 (2.39 μg), human hepato-cellular cell line HepG-2 (2.55 μg) and intestinal epithelium carcinoma Caco-2 (5.80 μg) cell lines, respectively. The oil cytotoxicity exceeded 1,8-cineole except for intestinal epithelium carcinoma Caco-2. Additionally, the antimicrobial activity was evaluated using agar disc diffusion and minimum inhibitory concentration where the oil exhibited the best activity against Penicillium italicum and Geotrichum candidum with minimum inhibitory concentration=0.49 and 0.98 μg, respectively. Structure elucidation of the pure compounds isolated from Calothamnus quadrifidus leaves was done according to their chromatographic behavior, chemical and spectroscopic data. These compounds were isolated for the first time from Calothamnus quadrifidus leaves and identified as gallic acid, gallic acid methyl ester, 7,4`-dimethoxy-apigenin, 6,7-dimethoxy-apigenin, (Bis[3(2-methyl propan-1- one)-2, 6 dihydroxy-4- methoxy phenyl] methane, quercetin 3-O-beta-D-arbinopyranoside and quercetin 3-O-beta-D-4C1-xylopyranoside. In addition to the molecular docking of novel compound 3 was done in peroxiredoxins and the binding mode was found. Conformation 2 was found to be the most stable and may be responsible for the antioxidant effect as it showed the best free binding energy and affinity when compared to conformations.