Zubeyde Akin Polat

In vitro evaluation of the amoebicidal activity of garlic (Allium sativum) extract on Acanthamoeba castellanii and its cytotoxic potential on corneal cells.

Free-living protozoa of the genus Acanthamoeba can cause one of the most severe, potentially sight-threatening infections of the eye, the so-called A. keratitis. A. keratitis is difficult to treat because, under adverse conditions, the amoeba encyst and medical therapy is often less effective against cysts than against trophozoites. The aim of this study was to investigate evaluate the in vitro effect of the nonpolar subfraction of the methanol extract of garlic (Allium sativum) on the growth of A. castellanii trophozoites and cysts and also its cytotoxicity on corneal cells in vitro. Extract was evaluated for its amoebicidal activity, using an inverted light microscope. The effect of the nonpolar extract with the concentrations, ranging from 0.78 to 62.5 mg/mL on the proliferation of A. castellanii trophozoites and cysts, were examined in vitro. For the determination of cytotoxicity of the extract on corneal cells, agar diffusion tests were performed. The present study demonstrates the in vitro effectiveness of the garlic against the A. castellanii growth curve. Evaluations revealed that garlic inhibits trophozoite growth in dose- and time-dependent ways. In the case of the cyctotoxic acitivities, it showed no cytotoxicity for the cornea cells in the concentration of 3.90 mg/mL. These findings indicate that nonpolar subfraction of the methanol extracts of garlic has amoebicidal, as well as its cysticidal, properties on Acanthamoeba trophozoites and cysts. Garlic alone, and in combination with other amoebicidal agents, may be used in clinical practices after further investigations.

Antitumoral effects of Melissa officinalis on breast cancer in vitro and in vivo.

BACKGROUND There is a long standing interest in the identification of medicinal plants and derived natural products for developing cancer therapeutics. Here we investigated the antiproliferative properties of Melissa officinalis (MO) from Turkey on breast cancer. METHODS MO extracts were studied for cytotoxicity against breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231). In vitro apoptosis studies were performed by annexin V staining and flow cytometry analyses. Immunohistochemistry for Ki-67 and caspase 7 in the tumoral tissue sections of DMBA-induced mammary tumors in rats was also performed, along with TUNEL assays to detect apoptotic cells. In vivo anticancer activity testing was carried out with reference to inhibition of growth of DMBA induced mammary tumors in rats. RESULTS MO showed cytotoxicity against three cancer cell lines, inducing increase in Annexin-positive cells. Expression of caspase-7 protein and TUNEL positive cells were much higher in rats treated by MO, compared with the untreated control group, while expression of Ki-67 was decreased. Furthermore, in vivo studies showed that mean tumor volume inhibition ratio in MO treated group was 40% compared with the untreated rats. CONCLUSION These results indicated that MO extrcts have antitumoral potential against breast cancer.

Antiangiogenic activities of bemiparin sodium, enoxaparin sodium, nadroparin calcium and tinzaparin sodium

INTRODUCTION The low-molecular-weight heparins have been demonstrated to have antiangiogenic effects in various assays. We aimed to demonstrate and compare the antiangiogenic effects of four types of commercially available low-molecular weight heparins in the chick embryo chorioallantoic membrane model. MATERIALS AND METHODS The antiangiogenic efficacies of bemiparin, enoxaparin, nadroparin, and tinzaparin were examined in vivo in the chick chorioallantoic membrane model. Drug solutions are prepared in three different concentrations (100 IU, 10 IU, or 1 IU/10 μl). For each set of experiment twenty fertilized eggs were used. The decrease of vessel formation is examined and scored according to previous literature. RESULTS Bemiparin, enoxaparin, nadroparin, and tinzaparin sodium all have antiangiogenic effects on chick chorioallantoic membrane at the concentration of 100 IU/10 μl. This effect was also observed in 10 IU/10 μl concentrations of nadroparin and tinzaparin. CONCLUSIONS The low molecular weight heparins studied have obvious antiangiogenic effects. There may be a difference in the potency of the drugs that could have a significant implication for further clinical research.

Miltefosine and polyhexamethylene biguanide: a new drug combination for the treatment of Acanthamoeba keratitis

In this study, a series of compounds – miltefosine, polyhexamethylene biguanide, chlorhexidine and propamidine isethionate – and combinations of the latter three agents with miltefosine were prepared and used in a rat model for the topical treatment of Acanthamoeba keratitis.

In Vitro Amoebicidal Activity of Salvia staminea and Salvia caespitosa on Acanthamoeba castellanii and Their Cytotoxic Potentials on Corneal Cells

BACKGROUND/AIMS Amoebic keratitis is difficult to treat with total efficacy in some patients because of cysts, which are less susceptible than trophozoites to the usual treatments. We investigated the in vitro effectiveness of methanolic extract of Salvia staminea and Salvia caespitosa against Acanthamoeba castellanii, as well as their cytotoxicity on corneal cells in vitro. METHODS Extracts were evaluated for their amoebicidal activities using an inverted light microscope. The effect of Savia species, with concentrations ranging between 1.0 and 32.0 mg/mL, on the proliferation of A. castellanii trophozoites and cysts were examined in vitro. For determining the cytotoxicity of Salvia species on corneal cells, agar diffusion tests were performed. RESULTS According to the results obtained from these tests, S. staminea showed remarkable amoebicidal effect on A. castellanii. In the case of the cytotoxic activity, methanolic extract of S. staminea showed no cytotoxicity on corneal cells with a concentration of 16 mg/mL. CONCLUSIONS Methanolic extract of S. staminea could be considered a new natural agent against Acanthamoeba. However, further evaluation by in vivo testing is needed to confirm the efficiency of its biological effect.

Sequential determination of serum viral titers, virus-specific IgG antibodies, and TNF-α, IL-6, IL-10, and IFN-γ levels in patients with Crimean-Congo hemorrhagic fever

BackgroundAlthough there have been a number of studies on the pathogenesis of Crimean-Congo hemorrhagic fever (CCHF) recently, knowledge on this topic is still insufficient. This study aims to reveal the kinetics of serum CCHF virus (CCHFV) titers, serum levels of anti-CCHFV immunoglobulin (Ig)G, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and interferon (IFN)-γ in CCHF patients.MethodsIn total, 31 CCHF cases (11 fatal) were studied. Serum samples were obtained daily from all patients from the time of admission and continued for a 7-day hospitalization period for serologic (ELISA), virologic (real-time PCR), and cytokine (ELISA) analysis.ResultsThe mean serum CCHFV titer at admission was 5.5E + 09 copies/mL in fatal cases and 5.7E + 08 copies/mL in survivors (p < 0.001). Compared to survivors, both the mean serum levels of IL-6 and TNF-α at admission were found to be significantly increased in fatal cases. The serum levels of IL-6, TNF-α and serum CCHFV titer at admission were significantly and positively correlated with disseminated intravascular coagulation (DIC) scores (r = 0.626, p = 0.0002; r = 0.461, p = 0.009; and r = 0.625, p = 0.003, respectively). When the data obtained from the sequential determination of CCHFV titer and levels of anti-CCHFV IgG, IL-6, TNF-α, IL-10 and IFN-γ were grouped according to the days of illness, the initial serum CCHFV titer of a fatal patient was 5.5E + 09 (copies/mL) and it was 6.1E + 09 (copies/mL) in a survivor on the 2 day of illness. While significant alterations were observed in all cytokines during the monitoring period, IL-6 levels remained consistently higher in fatal cases and TNF-α levels increased in both in fatal and non-fatal CCHF cases.ConclusionsThe increased CCHFV load and higher concentrations of IL-6 and TNF-α, the presence of DIC, and the absence of CCHFV specific immunity are strongly associated with death in CCHF.

Cytotoxicity Analysis of Strontium Ranelate on Cultured Human Periodontal Ligament Fibroblasts: A Preliminary Report

BACKGROUND/PURPOSE The aim of this study was to analyze the cytotoxicity of strontium ranelate (SR) on human periodontal ligament fibroblasts (PDL cells) in vitro. METHODS PDL cells were obtained from healthy human third molars and cultured in Dulbeccos Modified Eagles Medium. The experimental groups were: G1, cultures treated with fresh medium (control); and G2, G3, G4 and G5: treated with SR at 20, 10, 5 and 2.5 mg/mL, respectively. The experimental times were 1, 6, 12 and 24 hours (short-term) for viability, and 2, 4, 6 and 8 days (long-term) for cell survival. The cells were counted using a hemocytometer. Data were then analyzed by one-way ANOVA and Tukeys tests (p < 0.05). RESULTS Cultures treated with the highest SR concentrations (G2 and G3) had significantly lower cell viability and cell numbers (p < 0.05) than those in G1, G4 and G5. SR at 2.5 mg/mL was non-cytotoxic to PDL cells. CONCLUSION SR was non-toxic at appropriate concentrations. Preclinical tests are needed to further assess its safety and effectiveness for tooth resorption prior to clinical use.

In Vitro Amoebicidal Activity of a Ceragenin, Cationic Steroid Antibiotic-13, Against Acanthamoeba castellanii and Its Cytotoxic Potential

Acanthamoeba is a free-living amoeba causing a potentially blinding infection of the cornea. Acanthamoeba keratitis is difficult to treat, without total efficacy in some patients because of cysts that are less susceptible than trophozoites to the usual treatments. Contact lens wearers are most at risk and account for some 95% of cases. Cationic steroid antibiotic (CSA)-13 is a small molecule aminosterol that has been shown to mimic the activity of endogenous antimicrobial peptides and has bactericidal activity based on membrane disruption. We investigated here the in vitro effectiveness of CSA-13 with a concentration of 100, 75, 50, and 25  mg/mL on proliferation of Acanthamoeba castellanii trophozoites and cysts and cytotoxic potential. CSA-13 was evaluated for its amoebicidal activity using an inverted light microscope at 1, 2, 4, 8, 12, and 24  h. For the determination of cytotoxicity of the CSA-13 on L929 cells, agar diffusion tests were performed. CSA-13 inhibited trophozoite growth in dose- and time-dependent ways. At 1  h, no viable trophozoites were observed in the presence of CSA-13 solution in a concentration 100  mg/mL in phosphate-buffered saline. Results of cytotoxicity experiments demonstrated that CSA-13 solution had mild toxicity at 100  mg/mL concentration on cells, whereas it had no toxicity at 75  mg/mL concentration. The findings of this experiment as in vitro ameboebicidal activity for Acanthamoeba suggest that CSA-13 has a potential to be used as a new agent in lens solutions to prevent Acanthamoeba growth and infections.

The effect of propolis in experimental Acanthamoeba keratitis

Purpose:  To examine the effect of propolis in a rat model of Acanthamoeba keratitis and to determine its in vitro cytotoxicity in cultured corneal epithelial cells.

Comparison of the antiangiogenic effects of heparin sodium, enoxaparin sodium, and tinzaparin sodium by using chorioallantoic membrane assay.

Unfractionated heparin (UFH) and low molecular weight heparins have been used as anticoagulation agents in cardiovascular clinics for decades. However, these molecules also have potent antiangiogenic effects. Whereas, angiogenesis may be the most crucial determinant of the prognosis of cardiovascular diseases, and except some special situation, antiangiogenic effect is not desirable in the most of the cardiovascular disease. In this study, we aimed to compare the antiangiogenic potency of UFH, enoxaparin, and tinzaparin. The antiangiogenic efficacies of UFH, enoxaparin, and tinzaparin were examined in vivo by using the chick chorioallantoic membrane (CAM) model. Twenty fertilized eggs were used for each studied drug. Drug solutions were prepared in 10 and 1 IU/10 &mgr;l concentrations. Decreases in the density of the capillaries were assessed and scored. All three drugs showed antiangiogenic effects on the chick CAM at the 10 IU/10 &mgr;l concentration. However, the antiangiogenic score of the UFH was significantly higher than that of enoxaparin and tinzaparin at 1 and 10 IU/10 &mgr;l concentrations. UFH had stronger and antiangiogenic potential than enoxaparin and tinzaparin. However, tinzaparin showed dose-dependent antiangiogenic effects. We think that an anticoagulant molecule with a less and dose-dependent antiangiogenic effect, as in the case of tinzaparin, may be more desirable in case of cardiovascular disease related with insufficient angiogenesis.