Search

Objectives: In this study, it is aimed to examine the protective effect of magnolia extract (ME), a herbal material obtained from Magnolia Officinalis, which is claimed to have an important role in anti-inflammation, antioxidative stress and antiapoptosis, with increased reactive oxygen species (ROS) production due to aging and depolarized mitochondrial membrane potential (MMP) in cardiomyocytes and its suppressive effect on apoptosis and endoplasmic reticulum (ER) stress at the molecular level. Materials and Methods: In the study, an in vitro aging model was created using rat left ventricular cell line H9c2. H9c2 cells treated with D-galactose (D-Gal; 50 mg/mL) for 48 hours were incubated with 5 µM ME for 24 hours and their effects on ROS production and MMP depolarization in aged cardiomyocytes were examined. ROS and MMP measurements were performed under confocal microscopy using fluorescent dyes dichlorofluorescin diacetate (DCFDA) and carbonyl cyanide-p-trifluoromethoxyphenylhydrazone (FCCP). With the ER- stress markers Calregulin and glucose-regulated protein 78, qRT-PCR measurements of the change in expression of the apoptosis marker equilibrative nucleoside transporter 1 after ME treatment were analyzed. Results: Incubation of aging-modeled cardiomyocytes with ME provides significant suppression of aging-related ROS production and regulation of depolarized MMP. In addition, we observed that ER-stress and apoptosis developed by mitochondrial dysfunction were suppressed by ME treatment, by examining the expressions of stress and apoptosis marker genes. Conclusion: Our findings show that Magnolia officinalis extract, known for its cardioprotective effects, can be applied as a new treatment approach in aging-related heart failure by regulating mitochondrion dysfunction that develops uncontrollably with cardiac aging at the functional and molecular level. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to investigate in vitro effects of an antihelminthic drug niclosamide on human ovarian carcinoma cell line OVCAR-3. Methods: MTT assay was applied to investigate the cytotoxic effects of niclosamide on the cells. β-catenin levels in the cells were analyzed by immunocytochemistry, in order to assess the potency of niclosamide on Wnt/β-catenin signaling pathway that function in cell proliferation. The effects of the drug on apoptosis were detected by TUNEL method. All the assays were also performed for chemotherapy agent 5-fluorouracil (5-FU) and anticancer effects of these two drugs were compared. Results: It was found that niclosamide at 1 μM and 2 μM concentrations reduced cell viability, whereas 5-FU showed its significant proliferation inhibitory effect at higher concentrations. Niclosamide led to an increase in apoptosis while this effect was weaker compared with 5-FU. Niclosamide treatment decreased β-catenin staining in the cells significantly but 5-FU did not affect β-catenin levels. Conclusion: The results indicate that niclosamide induces apoptosis and suppresses cell proliferation by inhibiting Wnt/β-catenin signaling pathway in OVCAR-3 cells. In conclusion, these findings warrant further evaluation of niclosamide as a promising therapy for ovarian cancer. [ABSTRACT FROM AUTHOR]

Despite present-day clinical achievements which can extend the overall survival period, prostate cancer (PCa) related mortality remains a major problem. Resistance against apoptosis which consequently leads to disease prognosis is one of the most important characteristics of metastatic cancer cells which display a high level of genetic and clinical heterogeneity. Therefore, achievements in the local treatment of PCa have not been matched in the treatment of the metastatic disease. Although androgen deprivation therapy is the standard treatment due to the androgen receptor (AR) signaling pathway which has primary importance in metastatic cases, successful treatment remains difficult because of the genetic aberrations of ARs. Majority of the PCa patients develop resistance against androgen ablation within an average of 12-36 month-period and despite the castrate levels of testosterone, androgen-dependent and independent signals cause an increase in the cancer cells. While effective survival advantages displayed by the new generation agents like abiraterone and enzalutamide is promising in the treatment of metastatic castration resistant PCa how to best manage the primary and secondary resistance to treatment remains a challenge. The apoptotic effect enhancing pro-survival effectors and apoptotic regulators within the cytoprotective chaperone networks become more and more important every day for overcoming treatment resistance. Recent scientific research on apoptotic pathway inducing mechanisms focuses on the importance of developing synergistic treatment strategies. Molecules with lower side-effect profiles which are capable of inducing physiological mechanisms like apoptosis are expected to replace chemotherapeutic agents in the future. [ABSTRACT FROM AUTHOR]

Objective: STI571, a selective tyrosine kinase inhibitor is used in CML chemotherapy. It has limited effects in some cases due to drug resistance and intoxication as other chemotherapeutic agents. Thus, many cancer patients use dietary supplements and herbal extracts for increasing the effectiveness of chemotherapeutic agents. Theobromine, a metabolite of cacao has prooxidant effects and regulates intercellular signaling pathways. The aim of the study is to determine the potential apoptotic effects of STI571 and theobromine on K562 cells, when used alone and in combination. Methods: Inhibitory concentrations of STI571 and theobromine were determined by MTT method. Both agents were applied to the cells at 48 h time period alone and in combination. Caspase activities were assessed colorimetrically. Apoptosis and necrosis were evaluated by using acridine orange/ethidium bromide staining. p<0.05 was considered as statistically significant. Results: Caspase activities increased when both agents administrated alone. Theobromine increased effects of STI571 on caspase activities in time and type dependent manner (p<0.05). Apoptotic cell rates also increased when two agents applied in combination (p<0.05) in time dependent manner. Theobromine also reduced necrotic cell rates. Conclusion: Although there are limited data about the intracellular effects of theobromine, we showed that theobromine has effects on the caspase pathway related apoptotic response carried out by STI571. We believe that this in vitro study will shed light for further researches. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the apoptotic effects of intravitreal bevacizumab on rat retinal cells. Material and Method: Thirty-six male adult Swiss albino rats were randomly divided into two groups. The first group was applied 0.25 mg bevacizumab in 0.01 ml saline, and the second group received the same amount of saline intravitreally. Each group was divided into 3 subgroups. The animals were sacrificed and their globes were enucleated at the 3rd, 24th, and 72nd hours of the experiment. Enucleated eyes were preserved for histological analysis, immunohistochemical analysis of caspase-3, caspase-8, caspase-9, Fas/Fas L, VEGF and VEGF receptors (Flt-1, Flk-1), and TUNEL staining. Results: Histological evaluation showed no sign of retinal toxicity in both groups. In TUNEL staining, TUNEL(+) cells were detected in all subgroups, but the number of positive cells was relatively lower in bevacizumab treatment group that reached statistically significant level at 24 and 72 hours of treatment (p<0.001). Immunohistochemical analysis revealed that in saline-treated subgroups, immunoreactivity was more pronounced for all apoptosis-inducing proteins compared to bevacizumab-treated group. Also immunoreactivity of VEGF was prominent in saline treated group. For VEGF receptors, staining was only positive for Flt-1 at the 3rd hour in the control group. Discussion: Bevacizumab did not have apoptosis-inducing potential compared to saline solution in short term, which was documented with TUNEL and immunohistochemical staining. [ABSTRACT FROM AUTHOR]

Background and Design: Abnormal differentiation and hyperproliferation of keratinocytes are the hallmarks of psoriasis vulgaris. Although psoriasis vulgaris is generally accepted as a disease of decreased keratinocyte apoptosis, the results are contradictory. The aim of the current study is to investigate whether decreased keratinocyte apoptosis contributes to the formation of a thickened epidermis as increased keratinocyte proliferation. Material and Method: Forty-three untreated psoriasis vulgaris patients and 20 healthy control subjects were included into the study. Biopsy specimens taken from the enrollee were evaluated by immunohistochemical staining for Ki-67 expressions to show the proliferation of keratinocytes and by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nickend labeling (TUNEL) method to show the apoptotic keratinocytes. Results: Apoptotic index (percentage of the TUNEL positive cells) was significantly lower in psoriatic epidermis (0.33±0.64) than in normal epidermis (0.75±0.85); whereas Ki-67 index (percentage of positively staining cells for Ki-67) was significantly higher in psoriatic epidermis (30.86±10.49) than in normal epidermis (11.65±2.98), (p=0.021 and p=0.00; respectively). Conclusion: Decreased keratinocyte apoptosis also contribute to increased epidermal thickness in psoriasis as well as increased keratinocyte proliferation. [ABSTRACT FROM AUTHOR]

Objective: Tubal sterilization, is a common birth control method which the complication rates change according to the performed technique and methods. The aim of this study was to evaluate the effects of tubal sterilization techniques, Pomeroy and bilateral bipolar cautherization, on the apoptosis in the ovarian and endometrial tissue atrophy in rats. Materials and Methods: Thirty female Wistar Albino rats were enrolled in the study and divided into three groups (n=10). In the first group, rats underwent bilateral uterine horn ligation with Pomeroy method, in the second group, bilateral bipolar cauterization was applied, and only laparotomy was performed in the control group. Two months later, uterine horns and ovaries of the rats in all groups were excised. After genomic DNA isolation, DNA samples were run in agarose gel and the Scion Images were compared with the DNA marker and control. Results: There was no apoptosis in the ovarian and endometrial tissues in all groups detected by agarose gel electrophoresis and Scion Image technique. In Pomeroy group, there were both necrosis and intact DNA in ovarian and endometrial tissues, while in cauterization group, there were only necrosis. Discussion: In our study, there was no role of apoptosis in the atrophy of ovarian and endometrial tissues after tubal ligation by Pomeroy technique or bipolar cauterization in female rats. In Pomeroy technique, however, higher proportion of intact tissue was detected compared with bipolar cauterization. Further randomized controlled studies are needed to study the expression of atrophy and apoptosis. [ABSTRACT FROM AUTHOR]

Objective: Prostate cancer is one of the most common cancers in men and is the second leading cause of male cancer deaths after lung cancer. Activation of apoptosis is an important process to overcome prostate cancer. In this study, we investigated the synergistic anti-proliferative and apoptotic effects of metformin and dichloroacetate (DCA) in human prostate cancer cell line PC-3. Methods: PC-3 cells were cultured in plate before being exposed to different concentrations of unaccompanied metformin and DCA as well as metformin and DCA combination. Cell proliferation and viability were investigated with WST-1 assay. After the protein isolation from control and treated cells, whole cell lysate was used for determining caspase-3, -8 and -9 activation by western blotting method. Results: Our results demonstrated that both drugs were found effective for inhibiting cell proliferation. This inhibition effect was markedly enhanced with a low-dose 30mM DCA plus metformin (2.5mM) combination treatment. Our western blot results showed that caspase-3 and -9 were activated after the combination treatment, but caspase-8 was not activated, which suggests that intrinsic apoptosis pathway was activated by DCA and metformin in PC-3 cells. Conclusion: Metformin and DCA combinations demonstrated growth inhibiting effects on PC-3 prostate cancer cells with inhibition of cell proliferation and increased apoptosis by caspase activation. By the application of combined doses of these drugs, inhibition of viability and proliferation occurred at lower doses in cells. Further research work should be performed in order to further investigate these promising agents as therapeutics and adjuvant substances for prostate cancer. [ABSTRACT FROM AUTHOR]