Tannin extract from maritime pine bark exhibits anticancer properties by targeting the epigenetic UHRF1/DNMT1 tandem leading to the re-expression of TP73.

Maritime pine bark is a rich source of polyphenolic compounds and is commonly employed as a herbal supplement worldwide. This study was designed to check the potential of maritime pine tannin extract (MPTE) in anticancer therapy and to determine the underlying mechanism of action. Our results showed that MPTE, containing procyanidin oligomers and lanostane type terpenoids, has an inhibitory effect on cancer cell proliferation through cell cycle arrest in the G2/M phase. Treatment with MPTE also induced apoptosis in a concentration-dependent manner in human cancer cell lines (HeLa and U2OS), as evidenced by the enhanced activation of caspase 3 and the cleavage of PARP along with the downregulation of the antiapoptotic protein Bcl-2. Interestingly, human non-cancerous fibroblasts are much less sensitive to MPTE, suggesting that it preferentially targets cancer cells. MPTE played a pro-oxidant role in cancer cells and promoted the expression of the p73 tumor suppressor gene in p53-deficient cells. It also downregulated the protooncogenic proteins UHRF1 and DNMT1, mediators of the DNA methylation machinery, and reduced the global methylation levels in HeLa cells. Overall, our results show that maritime pine tannin extract can play a favorable role in cancer treatment, and can be further explored by the pharmaceutical industry.

Evaluation of Anticancer Potential of Flavones from Rhamnus alaternus against B16F10 Melanoma Cells.

Melanoma has become an important health problem and new treatment have become an imperative medical need. Therefore, the finding and identification of natural product with less toxic effects, capable of promoting melanoma cell death have become an important goal of research in oncotherapy. In this study, we want to investigate the anticancer activity of an enriched total oligomers flavonoids (TOF) extract of R. alaternus in melanoma cells. First, TOF was exhibited to be rich in flavones. We revealed that this extract reduced proliferation and increased of sub-G1 and S phase cells built-up in B16-F10 cells in a dose-related manner. Moreover, In Vivo, TOF reduced tumor volume and weight with percentages of inhibition of 92.4% and 92.9%, respectively. R. alaternus was also found to be effective in reducing the level of pro-inflammatory cytokine IL-6 during metastasis. Level of TH1 cytokine, such as IL-2, was significantly enhanced by TOF treatment. Indeed, the histological examination of the tumor revealed the absence of mitoses and the presence of numerous melanin pigmented macrophage cells in the R. alaternus extract-treated group that could be explained by the induction of macrophage activation and by the arrest of the cell cycle in the Sub-G1 and S phases.

Assessment of Rhamnus alaternus Leaves Extract: Phytochemical Characterization and Antimelanoma Activity.

Rhamnus alaternus (Rhamnaceae) has been used as a laxative, purgative, diuretic, antihypertensive, and depurative. However, few scientific research studies on its antimelanoma activity have been reported. This study aimed to investigate the in vitro antimelanoma effect of an enriched total oligomer flavonoid (TOF) extract, from R. alaternus, and to identify its phytochemical compounds. The chemical composition of TOF extract was assessed by HPLC-electrospray ionization tandem mass spectrometry (HPLC/ESI-MS2) analysis. Antimelanoma activity was determined on cultured tumor cell B16F10 by the crystal violet assay, the alkaline comet assay, acridine orange/ethidium bromide (AO/EB), annexin V-fluorescein isothiocyanate/ propidium iodide (V-FITC/PI) staining, the cell cycle distribution, and the wound healing assay. Regarding chemical composition, a mixture of quercetin diglucoside, quercetin-3-O-neohesperidoside, kaempferol-3-O-(2G-α-L-rhamnosyl)-rutinoside, rhamnetin hexoside, kaempferol-3-O-rutinoside, rhamnocitrin hexoside, pilosin hexoside, apigenin glucoside, and kaempferol-3-O-glucoside was identified as major phytochemical compounds of the extracts. TOF extract inhibits melanoma B16F10 cell proliferation in dose-dependent manner. The induction of apoptosis was confirmed by comet assay, AO/EB, and annexin V-FITC/PI test. TOF extract could also induce S phase cell cycle, inhibit, and delay the cell migration of B16F10 cells. The findings showed that TOF extract from R. alaternus could be a potentially good candidate for future use in alternative antimelanoma treatments.

Antitumor Effect of Bryonia dioïca Methanol Extract: In Vitro and In Vivo Study.

Aim: A large number of plant-derived products have been approved for the treatment of numerous types of cancer, and these products have also shown to reduce the effects of metastatic cancer. The aim of this study is to evaluate the anticancer effects of a methanolic extract of Bryonia dioïca root (M extract) against B16F10 melanoma cancer cells in vitro as well as in vivo.Results: It was shown to induce apoptosis, in vitro, and to inhibit cell growth by arresting cell cycle progression in SubG1 phase. Mice bearing the melanoma cells were used to confirm any in vivo effectiveness of the M extract as an antitumor promoting agent. In mice dosed with 50 mg M/kg/d (for 28 days), tumor weight was inhibited by 65.03% compared to that in mice that did not receive the product. Our results demonstrate on the one hand, that this inhibition was accompanied by a drastic decrease regulation of complex FAK, Src, ERK, p130Cas and paxillin. On the other hand, it was marked by a measurable decrease of the metastatic descent in the lungs.Conclusions: These effects could be ascribed to the presence of bryoniosides and cucurbitacins such as cucurbitacin A and cucurbitacin G in M extract.

Immunomodulatory and cellular anti-oxidant activities of caffeic, ferulic, and p-coumaric phenolic acids: a structure-activity relationship study.

Many studies have been performed to assess the potential utility of natural products as immunomodulatory agents to enhance host responses and to reduce damage to the human body. To determine whether phenolic compounds (caffeic, ferulic, and p-coumaric acids) have immunomodulatory effects and clarify which types of immune effector cells are stimulated in vitro, we evaluated their effect on splenocyte proliferation and lysosomal enzyme activity. We also investigated the activity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL). In addition, induction of the cellular antioxidant activity in splenocytes, macrophages, and red blood cells was determined by measuring the fluorescence of the DCF product. The study first results indicated that caffeic, ferulic, and p-coumaric acids significantly promote LPS-stimulated splenocyte proliferation, suggesting a potential activation of B cells, and enhanced humoral immune response in hosts treated by the tested natural products. Phenolic acids significantly enhanced the killing activity of isolated NK and CTL cells but had negligible effects on mitogen-induced proliferation of splenic T cells. We showed that caffeic acid enhances lysosomal enzyme activity in murine peritoneal macrophages, suggesting a potential role in activating such cells. Immunomodulatory activity was concomitant with the cellular antioxidant effect in macrophages and splenocytes of caffeic and ferulic acids. We conclude from this study that caffeic, ferulic, and p-coumaric acids exhibited an immunomodulatory effect which could be ascribed, in part, to their cytoprotective effect via their antioxidant capacity. Furthermore, these results suggest that these natural products could be potentially used to modulate immune cell functions in physiological and pathological conditions.

In Vitro and In Vivo Anti-Melanoma Effects of Pituranthos tortuosus Essential Oil Via Inhibition of FAK and Src Activities.

A large number of plants used in traditional medicines have been shown to possess antitumor activities. The aims of this study were to evaluate any anticancer effect of the essential oil (EO) extracted from P. tortuosus against B16F10 melanoma cancer cells in vitro as well as in vivo. In vitro, EO was shown to induce apoptosis and to inhibit migration and invasion processes. Further investigation revealed that EO decreased focal adhesion and invadopodia formation which was accompanied by a drastic downregulation of FAK, Src, ERK, p130Cas and paxillin. Moreover, EO treatment decreased the expression level of p190RhoGAP, and Grb2, which impair cell migration and actin assembly. Mice bearing the melanoma cells were used to confirm any in vivo effectiveness of the EO as an anti-tumor promoting agent. In mice dosed with 100 mg EO/kg/d (for 27 days), tumor weight was inhibited by 98% compared to that in mice that did not receive the product. In conclusion, these data suggested to us that an EO of P. tortuosus could evolve to be a potential medicinal resource for use in the treatment of cancers.

Immunomodulatory and cellular antioxidant activities of pure compounds from Teucrium ramosissimum Desf.

Evaluation of the immunomodulatory activity of plant compounds is an interesting and growing area of research. Teucrium ramosissimum Desf. is a native and endemic medicinal plant from the South of Tunisia traditionally used for the treatment of many diseases. The anti-inflammatory activity of apigenin-7-glucoside, genkwanin, and naringenin isolated from T. ramosissimum were assayed. The phagocytic activities of macrophage and lymphocyte proliferation were investigated in the absence and presence of mitogens (lipopolysaccharide [LPS] or lectin). Depending on the concentrations, the compounds affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide (NO) release. The tested compounds enhance significantly splenocyte proliferation, either with or without mitogen stimulation. In studies to assess any potential effects of apigenin-7-glucoside, genkwanin, and naringenin on innate immunity, the results showed that these compounds significantly enhanced the killing activity of natural killer (NK) cells and cytotoxic activity of the T lymphocyte (CTL) isolated from splenocytes. These results suggest that T. ramosissimum compounds such as apigenin-7-glucoside, genkwanin, and naringenin may be potentially useful for modulating immune cell functions in physiological and pathological conditions.

In vitro and in vivo anti-melanoma effects of Daphne gnidium aqueous extract via activation of the immune system.

The purpose of this study was to assess the antitumor and immunomodulatory effects of the aqueous extract from Daphne gnidium in mice-bearing melanoma tumor. Balb/C mice were subcutaneously implanted with B16-F10 cells and treated intraperitoneally with the aqueous extract at 200 mg/Kg b.w for 21 days. After euthanization on day 22, the tumors were weighed; lymphocyte proliferation, cytotoxic T lymphocyte (CTL), and natural killer (NK) cell activities were evaluated using the MTT assay. Macrophage phagocytosis was studied by measuring the lysosomal activity. In addition to its potential to inhibit the growth of the transplantable tumor, the aqueous extract remarkably induced splenocyte proliferation and both NK and CTL activities in tumor-bearing mice. The aqueous extract was also seen to have promoted lysosomal activity of host macrophages.

Limoniastrum guyonianum methanol extract induces immunomodulatory and anti-inflammatory effects by activating cellular anti-oxidant activity.

Evaluation of the immunomodulatory activity of plant extracts is an interesting and growing area of research. In this study, effects of a methanolic extract of Limoniastrum guyonianum stems (M extract) on mice immune cell function in vitro were investigated. These studies showed that mitogen-induced lymphocyte proliferation was dose-dependently inhibited by the extract. Further, the lectin-induced response appeared to be more sensitive to the suppressive effects of the extract than were LPS-stimulated responses. In studies to assess any potential effects of extract on innate immunity, the results showed that the extract significantly enhanced the killing activity of isolated NK cells. In addition, studies here demonstrated that the extract could enhance lysosomal enzyme activity and inhibit nitrite oxide (NO) production by murine peritoneal macrophages ex vivo, suggesting a potential anti-inflammatory effect in situ. The anti-inflammatory activity was concomitant with the cellular anti-oxidant effect in macrophages and splenocytes.

In vitro antileukaemic activity of extracts from Daphne gnidium leaves against sensitive and multidrug resistant K562/R7 cells.

The antiproliferative potential of extracts of Daphne gnidium L. (Thymelaeaceae) on K562 cells was assessed, and the capacity of these extracts to disturb the cell cycle of K562 cells and to inhibit human P-glycoprotein was evaluated. The antiproliferative activity was evaluated using the MTT assay. The cell cycle analysis and the inhibition of P-glycoprotein were tested by flow cytometry. All the tested extracts exhibited significant anti-proliferative effects. Ethyl acetate extract has the strongest cytotoxic effect with an IC50 of 18.5 µg/ml. Furthermore, cell cycle analysis revealed that cells treated with chloroform, butanol and aqueous extracts were arrested predominantly in G2-M phase. Butanol extract was the most active extract. Percentage of cells arrested in G2-M was 34 %, 36.67 % and 42.63 % respectively, after treatment with 25, 75 and 100 µg/ml of the extract, versus 19 % in the cells treated with the vehicle solvent. In addition, chloroform extract had the ability to inhibit human P-glycoprotein-mediated daunorubicin in K562/R7 leukaemic cells in a dose-dependent manner compared to the positive control, cyclosporin A. These findings demonstrate that extracts from D. gnidium leaves have antileukaemic activity by perturbing the cell cycle of K562 and inhibiting human P-glycoprotein in K562/R7 cell line.

Limoniastrum guyonianum aqueous gall extract induces apoptosis in colorectal cancer cells by inhibiting calpain activity.

Several studies have reported that plant-derived natural products have cancer chemopreventive and chemotherapeutic properties. The aim of the present study was to determine the antiproliferative and pro-apoptotic potential of Limoniastrum guyonianum aqueous gall extract (G extract) on human colorectal cancer BE cell line and, if so, to characterize the mechanism involved. The G extract-induced growth inhibitory effect was associated with an arrest of cell cycle progression in G2/M phase as shown by the cell phase distribution. In addition, G extract promoted in a concentration-dependent manner these cells towards apoptosis as indicated by the presence of cleaved poly(ADP-ribose) polymerase (PARP). In order to characterize the mechanism involved in the antiproliferative and pro-apoptotic signaling pathway activated by G extract, calpain activity and the expression of the cell cycle inhibitor p16(INK4A) were determined. The present findings indicated that G extract exhibited significant inhibitory activity against calpain and caused a marked and concentration-dependent upregulation of p16(INK4A). These effects could be ascribed to the presence of condensed tannins and polyphenols such as epicatechin and epigallocatechin gallate in G extract.

An aqueous extract of Limoniastrum guyonianum gall induces anti-tumor effects in melanoma-injected mice via modulation of the immune response.

The objectives of this study were to evaluate the in vitro and in vivo anti-tumor potential of the aqueous gall extract (G extract) from Limoniastrum guyonianum and to elucidate its immunological mechanisms, in part, by assessing its effects on the growth of transplanted tumors and the immune response in these tumor-bearing mice. Here, mice were inoculated with B16F10 mouse tumor cells and then treated intraperitoneally with G extract at 25 or 50 mg extract/kg BW for 7, 14, or 21 days. At each timepoint, effects of the extract on the tumor growth, splenocytes proliferation, NK cell activity, and CTL activity among splenocytes isolated from the mice were measured. G extract-induced tumor growth inhibition was associated with characteristic apoptotic changes in the tumor cells, like nuclear condensation. In addition, the extract inhibited melanin synthesis and tyrosinase activity among melanoma cells in a concentration-related manner. G extract did not only significantly inhibit the growth of the transplantable tumor, but also remarkably increased splenocytes proliferation and both NK and CTL activities in tumor-bearing mice. The extract was also seen to have promoted lysosomal activity of host macrophages and gave rise to enhanced cellular anti-oxidant activity in several cell types in mice.

Antioxidant, mutagenic and antimutagenic activities of an aqueous extract of Limoniastrum guyonianum gall.

An aqueous extract of Limoniastrum guyonianum gall (G extract) was tested on Salmonella typhimurium to assess its mutagenic and antimutagenic effects. This extract showed no mutagenicity when tested with S. typhimurium strain TA104 either with or without exogenous metabolic activation mixture (S9), whereas our findings revealed that the aqueous gall extract induced a mutagenic effect in S. typhimurium TA1538 when tested in the presence, as well as in the absence, of S9 activation mixture at the concentration of 500 µg/mL. Thus, the same concentration produced a mutagenic effect, when incubated with S. typhimurium TA100 in the presence of metabolic activation mixture. In contrast, our results showed a weak antimutagenic potential of the same extract against sodium azide in the presence of S. typhimurium TA100 and S. typhimurium TA1538 without metabolic activation (S9), whereas, in the presence of S. typhimurium TA104, we obtained a significant inhibition percentage (76.39%) toward 3.25 µg/plate of methylmethanesulfonate. Antimutagenicity against aflatoxin B1, 4-nitro-o-phenylene-diamine and 2-aminoanthracène was significant, with an inhibition percentage of, respectively, 70.63, 99.3 and 63.37% in the presence of, respectively, S. typhimurium TA100, S. typhimurium TA1538 and S. typhimurium TA104 strains at a concentration of 250 µg/plate after metabolic activation (S9). Antioxidant capacity of the tested extract was evaluated using the enzymatic (xanthine/xanthine oxidase assay) and the nonenzymatic (2,2-diphenyl-1-picrylhydrazyl) system. G extract exhibited high antioxidant activity.

Evaluation of in vitro antioxidant and apoptotic activities of Cyperus rotundus

OBJECTIVE@#To evaluate in vitro antioxidant and apoptotic activities of Cyperus rotundus (C. rotundus).@*METHODS@#The phytochemical study and the antioxidant activities of both methanol and aqueous extracts from C. rotundus aerial part were determined. In addition, these extracts were also investigated for their cytotoxic and apoptotic activities. The major compound of the methanol extract was isolated. Both methanol and aqueous extracts (300, 150, and 50 μg/mL) were evaluated for their antioxidant activity by the xanthine/xanthine oxidase assay system. However, 16, 8, and 4 mg/mL of each extract were tested to investigate their OH. formation scavenging potential. Aqueous extract (800, 400, and 200 μg/mL) and methanol extract (350, 175, and 88 μg/mL) were tested against lipid peroxidation, induced by 75 μM H2O2. The cytotoxicity (by MTT assay) and cell DNA fragmentation of both extracts were evaluated towards K562 and L1210 cell lines. The major compound was obtained from the butanol fraction of methanol extract and its structure was determined by RMN spectroscopic analysis.@*RESULTS@#The methanol and aqueous extracts showed respectively, 88% and 19% inhibition of xanthine oxidase activity. Yet, the same extracts inhibited lipid peroxidation by 61.5% and 42.0%, respectively. Both extracts inhibited OH. formation by 27.1% and 25.3%, respectively. Only methanol extract induced DNA degradation. Orientin was determined as the major compound isolated from the butanol fraction of methanol extract.@*CONCLUSIONS@#It appears that C. rotundus extracts exhibit a potential use as a natural antioxidant and an apoptosis inducer.

Immunomodulatory and cellular anti-oxidant activities of an aqueous extract of Limoniastrum guyonianum gall.

ETHNOPHARMACOLOGICAL RELEVANCE: Many studies have been performed to assess the potential utility of natural products as immunomodulatory agents to enhance host responses to disease/infection/etc. or to ameliorate immune based pathologies (i.e., inflammation, autoimmune associated diseases, etc.). In this particular study, the immunomodulatory potential of gall aqueous extract from Limoniastrum guyonianum Boiss. (Zita) was assessed in vitro. MATERIALS AND METHODS: The effect of G extract on splenocytes proliferation and NK activity were assessed by MTT test. The induction of NO production and the phagocytic activity of macrophages were evaluated in vitro. Activation of the cellular anti-oxidant activity in splenocytes was determined by measuring the fluorescence of the DCF product. RESULTS: The studies first demonstrated that the extract could enhance lysosomal enzyme activity and nitrite oxide production in murine peritoneal macrophages, suggesting a potential role in activation of these cells. In studies to assess potential effects on humoral immunity, the results indicated that the extract could significantly promote LPS-stimulated splenocyte proliferation implying a potential activation of B-cells and enhanced humoral immune responses in hosts given this natural product. In studies to assess any effects of extract on cellular immunity, the results showed that the extract significantly enhanced the killing activity of isolated NK cells but had negligible effects on mitogen-induced proliferation of splenic T-cells. Considerable effects were also observed on the cellular anti-oxidant activity. CONCLUSION: We conclude from these studies that aqueous extract from L. guyonianum gall exhibited an immunomodulator effect which could be ascribed, in part, to its cytoprotective effect via its anti-oxidant capacity. Furthermore, these results suggest that L. guyonianum gall extract contains potent components such as flavonoids which should be potentially used to modulate immune cell functions in physiological and pathological conditions.

In vitro and in vivo immunomodulatory and anti-ulcerogenic activities of Teucrium ramosissimum extracts.

Teucrium ramosissimum (Lamiaceae), a native and endemic plant from South Tunisia, has traditionally been used as a treatment for inflammation and for ulcers. Though the plant and its products are widely used, very few studies have analyzed the pharmacological/toxicological properties of this plant. Thus, the aim of these studies was to evaluate the anti-inflammatory/anti-ulcerogenic activities of various extracts (i.e., methanolic, aqueous, and total oligomer flavonoid [TOF]-enriched) from leaves of T. ramosissimum. In vitro, the effects from each extract on lysosomal enzyme activity and proliferation of, respectively, freshly isolated peritoneal macrophages and splenic lymphocytes were assessed. The extracts alone clearly affected macrophage function, as evidenced by a significant modulation of cell lysosomal enzyme activity and ability to form and/or release nitric oxide. These extracts were also found to be able to significantly modify the proliferation of splenocytes, even when lipopolysaccharide or lectin mitogens were absent. With respect to the anti-ulcerogenic activity of the extracts, these studies found that the leaf extracts were able to exert significant protective effects against ethanol-induced ulcers in a rat model; at some doses, the extract effects were even greater than that obtained using a cytoprotective histamine H2-antagonist, cimetidine. Based on these studies, we conclude that the extracts from T. ramosissimum appear to be potentially potent modulators of innate immunity and that their efficacy against ulcer formation may be due, in part, to a cytoprotective effect. Further, these results fortify the ethnopharmacological importance of the use of T. ramosissimum products as anti-inflammatory and anti-ulcer agents. Nevertheless, ongoing/further studies are needed to clarify more precisely mechanisms underlying effects against ulcers and on lymphocyte and macrophage functionality, as well as the causative agents.

Anti-inflammatory and antiulcerogenic activities of leaf extracts and sesquiterpene from Teucrium ramosissimum (Lamiaceae).

Teucrium ramosissimum (Lamiaceae) is a native and endemic medicinal plant from South of Tunisia traditionally used for the treatment of many diseases. The anti-inflammatory and antiulcerogenic activities of sesquiterpene (ß-eudesmol), chloroform, and ethyl acetate leaf extracts from T. ramosissimum were assayed. Macrophage phagocytic activity and lymphocyte proliferation in the absence and presence of mitogens (lipopolysaccharide [LPS] or lectin) were investigated. Depending on the concentrations, the extracts affect macrophage functions by modulating their lysosomal enzyme activity and nitric oxide (NO) release. For lymphocyte proliferation assay, tested extracts enhance significantly cell proliferation either with or without mitogen stimulation. These results suggest that leaf extracts from T. ramosissimum contain potent components such as flavonoids that may be potentially useful for modulating immune cell functions in physiological and pathological conditions. Antiulcerogenic activity was examined on rat ethanol-induced ulcerogenic model. Compared with control (cimetidine), leaf extracts from T. ramosissimum exert different protective effects against ethanol-induced ulcerogenesis.