Meral Sarper

Antimicrobial activity against periodontopathogenic bacteria, antioxidant and cytotoxic effects of various extracts from endemic Thermopsis turcica

OBJECTIVE To investigate the in vitro antimicrobial potential of Thermopsis turcica Kit Tan, Vural & Küçüködük against periodontopathogenic bacteria, its antioxidant activity and cytotoxic effect on various cancer cell lines. METHODS In vitro antimicrobial activities of ethanol, methanol, ethyl acetate (EtAc), n-hexane and water extracts of Thermopsis turcica herb against periodontopathogenic bacteria, Aggregatibacter actinomycetemcomitans ATCC 29523 and Porphyromonas gingivalis ATCC 33277 were tested by agar well diffusion, minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Antioxidant properties of the extracts were evaluated by 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity and β-carotene bleaching methods. Amounts of phenolic contents of the extracts were also analysed by using the Folin-Ciocalteu reagent. Additionally, cytotoxic activity of the extracts on androgen-insensitive prostate cancer, androgen-sensitive prostate cancer, chronic myelogenous leukemia and acute promyelocytic leukemia human cancer cell lines were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Human gingival fibroblast cells were used as a control. RESULTS Our data showed that EtAc extract had the highest antimicrobial effect on Aggregatibacter actinomycetemcomitans (MIC: 1.562 mg/mL, MBC: 3.124 mg/mL) and Porphyromonas gingivalis (MIC: 0.781 mg/mL, MBC: 1.562 mg/mL). In antioxidant assays, EtAc extract exhibited also the highest radical scavenging activity [IC50=(30.0±0.3) µg/mL] and the highest inhibition [(74.35±0.30)%] against lineloic acide oxidation. The amount of phenolic content of it was also the highest [(162.5±1.2) µg/mg gallic acid]. In cytotoxic assay, only ethanol [IC50=(80.00±1.21) µg/mL] and EtAc extract [IC50=(70.0±0.9) µg/mL] were toxic on acute promyelocytic leukemia cells at 20-100 µg/mL (P<0.05). However, no toxic effect was observed on human gingival fibroblast cells. CONCLUSIONS According to our findings, owing to its antioxidant and cytotoxic potential, EtAc extract might include anticancer agents for acute promyelocytic leukemia.

Effects of "iRoot BP" and "white mineral trioxide aggregate" on cell viability and the expression of genes associated with mineralization

AIM To evaluate the cytotoxicity and mineralization effects of iRoot BP in human dental pulp cells (hDPCs) and to compare them with those of white mineral trioxide aggregate (WMTA). METHODOLOGY hDPCs were exposed to prepared dilutions (1 : 1-1 : 10) of the test materials. Cell viability was evaluated using the XTT assay after incubation periods of 24, 48 or 72 h. The expression of mineralization-related genes (bone morphogenic protein, osteonectin, bone sialoprotein, osteopontin, dentine sialophosphoprotein and collagen type 1) and heme oxygenase 1 was measured by quantitative real-time polymerase chain reaction (qRT-PCR) at 24 and 72 h. Statistical differences between test materials were analysed with the Mann-Whitney test. RESULTS The 1 : 1 and 1 : 2 dilutions of iRoot BP were associated with higher cell viability after 24 h (P < 0.05). Only the 1 : 1 dilution of iRoot BP had higher cell viability after 48 h (P < 0.05), and there was no difference between iRoot BP and WMTA after 72 h (P > 0.05). Although somewhat variable, according to the gene expression results, iRoot BP had a mineralization potential similar to that of WMTA. WMTA revealed a higher heme oxygenase 1 (HO-1) mRNA level than iRoot BP (P < 0.001). CONCLUSIONS iRoot BP and WMTA were biocompatible and facilitated odontoblastic differentiation of hDPCs.

In vitro anti-oxidant, cytotoxic and pro-apoptotic effects of Achillea teretifolia Willd extracts on human prostate cancer cell lines

Background: The majority of Achillea species are the most important native economic plants of Anatolia. They include highly bioactive compounds, so they have therapeutic applications. Objective: In the present study, the aim was to investigate in vitro anti-oxidant, cytotoxic and pro-apoptotic effects of Achillea teretifolia Willd extracts (Turkish name: Beyaz civanperÇemi). Materials and Methods: The anti-oxidant potential of the extracts was analyzed by the free radical 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and total phenolic content methods. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to detect cytotoxicity of the extracts onhuman prostate cancer cell lines (DU145 and PC-3) and human gingival fibroblast (HGF) cells. mRNA expression levels of pro-apoptotic (bax, caspase-3) and anti-apoptotic (bcl-2) genes were measured by quantitative real-time polymerase chain reaction. Results: The results showed that extracts exhibited a remarkable DPPH scavenging activity, and total phenolic content of the methanol extract was higher than that of the water extract. As time and concentration were increased, the methanol extract exhibited a more powerful cytotoxic effect on prostate cancer cells. In prostate cancer cells, the levels of mRNA expression of the bax and caspase-3 genes were significantly up-regulated (P < 0.05), whereas the expression of bcl-2 was down-regulated (P < 0.05). In HGF cells, there were no cytotoxic effect and apoptosis induction triggered by the extracts. Conclusion: The methanol extract had more powerful anti-oxidant, cytotoxic and pro-apoptotic effects than the water extract. The extracts could be good anti-oxidant sources, and they might include anti-cancer compounds triggering the cytotoxicity and the apoptosis on prostate cancer cells.

Hypoxia inhibits mineralization ability of human dental pulp cells treated with TEGDMA but increases cell survival in accordance with the culture time.

OBJECTIVE To evaluate the cytotoxicity and mineralization effects of TEGDMA in human dental pulp cells (hDPCs) under hypoxic and normoxic culture conditions. DESIGN Cell viability was evaluated using XTT assay after incubation periods of 24, 48, or 72h. The expression of mineralization-related genes (osteonectin, osteopontin, dentin sialophosphoprotein, collagen type 1) and heme oxygenase 1 (HO-1) was assessed by quantitative real-time polymerase chain reaction at 24 and 72h. RESULTS In XTT assay, viability was higher in 0.3, 1, 2, 4, and 5mM groups in the presence of 21% O2 after 24h (p<0.05). Additionally, while 0.3, 1, 2mM groups had higher cell viability in the presence of 21% O2 after 48h (p<0.05), in 3mM groups cell viability was higher under 3% O2 than 21% O2 after both 24 and 48h (p<0.05). 1-3mM groups had higher cell viability under 3% O2 after 72h (p<0.05). There was no difference between 4 and 5mM groups with regards to cell viability after 48 or 72h (p>0.05). In the gene expression study, TEGDMA-treated hDPCs showed lower mineralization potential in the presence of 3% than with 21% O2 (p<0.05). hDPCs revealed higher HO 1 expression in 0.3 and 1mM groups under hypoxic than under normoxic conditions after a 72-h time period (p<0.001). CONCLUSIONS Hypoxic conditions increased cell survival in accordance with the culture period but inhibited the odontoblastic differentiation of hDPCs treated with TEGDMA.

The -137G/C Polymorphism in Interleukin-18 Gene Promoter Contributes to Chronic Lymphocytic and Chronic Myelogenous Leukemia Risk in Turkish Patients.

Objective: Interleukin-18 (IL-18) is a cytokine that belongs to the IL-1 superfamily and is secreted by various immune and nonimmune cells. Evidence has shown that IL-18 has both anticancer and procancer effects. The aim of this study was to evaluate the relationship between IL-18 gene polymorphisms and susceptibility to chronic lymphocytic leukemias (CLL) and chronic myelogenous leukemias (CML) in Turkish patients. Materials and Methods: The frequencies of polymorphisms (rs61667799(G/T), rs5744227(C/G), rs5744228(A/G), and rs187238(G/C)) were studied in 20 CLL patients, 30 CML patients, and 30 healthy individuals. The genotyping was performed by polymerase chain reaction and DNA sequencing analysis. Results: Significant associations were detected between the IL-18 rs187238(G/C) polymorphism and chronic leukemia. A higher prevalence of the C allele was found in CML cases with respect to controls. The GC heterozygous and CC homozygous genotypes were associated with risk of CML when compared with controls. However, prevalence of the C allele was not significantly high in CLL cases with respect to controls. There was only a significant difference between the homozygous CC genotype of CLL patients and the control group; thus, it can be concluded that the CC genotype may be associated with the risk of CLL. Based on our data, there were no significant associations between the IL-18 rs61667799(G/T), rs5744227(C/G), or rs5744228(A/G) polymorphisms and CLL or CML. Conclusions: IL-18 gene promoter rs187238(G/C) polymorphism is associated with chronic leukemia in the Turkish population. However, due to the limited number of studied patients, these are preliminary results that show the association between -137G/C polymorphism and patients (CLL and CML). Further large-scale studies combined with haplotype and expression analysis are required to validate the current findings.

Gene expression changes in bioceramic paste-treated human dental pulp cells

We evaluated the gene expression profiles of human dental pulp cells exposed to iRoot BP using microarray after 24 and 72 h. The results were verified using quantitative reverse transcriptase PCR analysis. Of the 36,000 transcripts arrayed, 21 were up-regulated and 15 were down-regulated by more than two fold. The largest group of up-regulated genes included those involved in nucleobase-containing compound metabolic processes, cell communication, protein metabolic processes, developmental processes, and biological regulation. The largest groups of down-regulated genes were those involved in cell communication, development, and biological regulation processes. In conclusion, iRoot BP affects the expression of genes involved in different biological processes in human dental pulp cells. (J Oral Sci 58, 307-315, 2016).

Microarray analysis of the gene expression profile in triethylene glycol dimethacrylate-treated human dental pulp cells

Objective: Triethylene glycol dimethacrylate (TEGDMA) is an important resin monomer commonly used in the structure of dental restorative materials. Recent studies have shown that unpolymerized resin monomers may be released into the oral environment and cause harmful biological effects. We investigated changes in the gene expression profiles of TEGDMA-treated human dental pulp cells (hDPCs) following short- (1-day) and long-term (7-days) exposure. Materials and Methods: HDPCs were exposed to a noncytotoxic concentration of TEGDMA, and gene expression profiles were evaluated by microarray analysis. The results were confirmed by quantitative reverse-transcriptase PCR (qRT PCR). Results: In total, 1282 and 1319 genes (up- or down-regulated) were differentially expressed compared with control group after the 1- and 7-day incubation periods, respectively. Biological ontology-based analyses revealed that metabolic, cellular, and developmental processes constituted the largest groups of biological functional processes. qRT-PCR analysis on bone morphogenetic protein-2 (BMP-2), BMP-4, secreted protein, acidic, cysteine-rich, collagen type I alpha 1, oxidative stress-induced growth inhibitor 1, MMP3, interleukin-6, and heme oxygenase-1 genes confirmed the changes in expression observed in the microarray analysis. Conclusions: Our results suggest that TEGDMA can change the many functions of hDPCs through large changes in gene expression levels and complex interactions with different signaling pathways.

Improvement of a liposomal formulation with a native molecule: calcitriol

Many studies have been conducted to improve liposomes potency towards cancer treatment. Recently, modifications of liposomal formulations turned towards either dual loading of anticancer agents to minimize the dose of each agent or the use of targeting moieties to target them to or near cancer cells for minimizing side effects with maximum treatment. In this study, a natural molecule, calcitriol, was used to improve the effectiveness of doxorubicin loaded liposomes by co-loading approach. Calcitriol treatment alone was reported to create an anti-proliferative effect on several carcinoma cell lines. However, to create an antiproliferative effect, a high dose of calcitriol needs to be used which might result in hypercalcemia. Therefore, co-loading calcitriol into liposomes will improve its efficiency on cells besides increasing hydrophobic calcitriols chemical stability in circulation. At first, possible doxorubicin cytotoxicity improvement against Namalwa cells by calcitriol pretreatment was investigated. The enhancing effect created was over 40% after 72 hours of calcitriol pretreatment. Upon co-loading into liposomes, enhanced and early cytotoxicity was observed even after 24 hours. Hence, the synergistic effect of calcitriol and doxorubicin on Namalwa cells was shown both in free and liposomal forms for the first time. A confocal study confirmed that early cytotoxicity was related with cell internalization. This potency ended when liposomes targeted non-internalizing antigen, CD20. Liposome co-loading of calcitriol and doxorubicin increases the effectiveness of their synergistic activity by creating a dual delivery system. Liposomal co-loaded calcitriol delivery would overcome calcitriol dose limitation problems and decrease possible side effects of both therapeutic agents.