Influences of periodontitis on hippocampal inflammation, oxidative stress, and apoptosis in rats.

BACKGROUND AND AIM: The hippocampus, which has a central role in cognitive and behavioral activities, is one of the most sensitive parts of the brain to systemic inflammatory diseases. This animal study aims to comprehensively investigate the possible inflammatory, oxidative, and apoptotic effects of periodontitis on the hippocampus. METHODS: Sixteen male Sprague-Dawley rats were randomly assigned to two groups: control and experimental periodontitis (Ep). In the Ep group, periodontitis was induced by placing 3.0 sutures sub-paramarginally around the necks of right and left mandibular first molars and maintaining the ligatures in place for 5 weeks. Following the euthanasia, mandibula and hippocampus samples were collected bilaterally. Alveolar bone loss was measured histomorphometrically and radiologically on the right and left mandibles. On the right hippocampal sections histological (Caspase-3, TNF-α, and 8-OHdG) and the left hippocampal sections, biochemical (IL-1ß, Aß1-42 , MDA, GSH, and TAS levels) evaluations were performed. RESULTS: Histopathological changes associated with periodontitis were limited (p > .05). A slight increase in caspase-3 positive neuron density in EP rats showed that apoptotic changes were also limited (p > .05). 8-OHdG activity, on the other hand, was significantly higher compared to controls (p < .05). In biochemical analysis, there was a significant increase in IL-1ß levels and oxidative membrane damage (MDA) (p < .05) whereas Aß1-42 and antioxidant marker (GSH and TAS) levels were slightly increased (p > .05). CONCLUSION: Periodontitis causes marked increases in IL-1ß levels and oxidative stress in the hippocampus, but limited degenerative and apoptotic changes.

Determination of modifications in rat liver due to phthalate uptake by SAM, RS, and ICP-OES.

The use of phthalates as plasticizers has been omnipresent, especially in cosmetics and food packaging, despite the proven effects on some organs of humans and animals. Therefore, alterations in living organisms due to phthalate exposure attract the attention of many scientists. Here, we demonstrate a mechanical and chemical investigation of the mentioned effects of di(2-ethylhexyl)phthalate (DEHP) and dibutyl phthalate (DBP) on rat liver by utilizing scanning acoustic microscopy (SAM), Raman spectroscopy (RS) and inductively coupled plasma optical emission spectrometry (ICP-OES) for the first time in the literature, as far as we know. The combined analysis gives insights into the degree of modification in the tissue components and which chemicals lead to these modifications. Our study shows that the acoustic impedance values of tissues of DEHP and DBP delivered mother rats are higher than those of tissues of the control mother rat, while the acoustic impedance values of tissues of offspring rats of DEHP and DBP delivered mother rats do not differ significantly from those of tissues of the control offspring rats of the control mother rat. Besides, RS analysis shows how the incorporation of DEHP into liver tissues changes the configuration and conformation of lipids and fatty acids. ICP-OES results show increased element levels within the tissues of DEHP and DBP delivered rats. Therefore, we can say that phthalates cause modifications within the liver. This study is a preliminary effort to investigate tissues with a mechano-chemical probe.

Melatonin improves periodontitis-induced kidney damage by decreasing inflammatory stress and apoptosis in rats.

BACKGROUND: Two main aims of this animal study were to inspect the possible effects of periodontitis on the structure and functions of the kidneys and the therapeutic effectiveness of melatonin. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups: control, experimental periodontitis (Ep), and Ep-melatonin (Ep-Mel). Periodontitis was induced by placing 3.0-silk sutures sub-paramarginally around the cervix of right-left mandibular first molars and maintaining the sutures for 5 weeks. Then melatonin (10 mg/kg body weight/day, 14 days), and the vehicle was administered intraperitonally. Mandibular and kidney tissue samples were obtained following the euthanasia. Periodontal bone loss was measured via histological and microcomputed tomographic slices. On right kidney histopathological and immunohistochemical, and on the left kidney biochemical (malonyl-aldehyde [MDA], glutathione, oxidative stress [OSI], tumor necrosis factor [TNF]-α, interleukin [IL]-1ß, matrix metalloproteinase [MMP]-8, MMP-9, and cathepsin D levels) evaluations were performed. Renal functional status was analyzed by levels of serum creatinine, urea, cystatin-C, and urea creatinine. RESULTS: Melatonin significantly restricted ligature-induced periodontal bone loss (P <0 .01) and suppressed the levels of proinflammatory cytokines (TNF-α and IL-1ß), oxidative stress (MDA and OSI), and proteases (MMP-8, MMP-9, and CtD) that was significantly higher in the kidneys of the rats with periodontitis (P <0.05). In addition, periodontitis-related histological damages and apoptotic activity were also significantly lower in the Ep-Mel group (P <0.05). However, the markers of renal function of the Ep group were detected slightly impaired in comparison with the control group (P >0.05); and the therapeutic activity of melatonin was limited (P >0.05). CONCLUSION: Melatonin restricts the periodontitis-induced inflammatory stress, apoptosis, and structural but not functional impairments.

Melatonin ameliorates periodontitis-related inflammatory stress at cardiac left ventricular tissues in rats.

BACKGROUND: The aim of this experimental rat study was to investigate the potential inflammatory effects of periodontitis on cardiac left ventricular tissue and the therapeutic activity of melatonin on these effects. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups: control, experimental periodontitis (Ep), and Ep-melatonin (Ep-Mel). Experimental periodontitis was induced by placing and maintaining 3.0 silk ligatures at a peri marginal position on the left and right mandibular first molars for 5 weeks. Afterward, following the removal of ligatures, melatonin (10 mg/body weight) to Ep-Mel group, and vehicle (saline) to Ep and control groups were administered intraperitoneally for 14 days. On the first day of the eighth week, mandibular and cardiac left ventricular tissue samples were obtained following the euthanasia of the rats in all groups. Alveolar bone loss measurements were made on histological and microcomputed tomographic slices. Cardiac tissue levels of malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), matrix metalloproteinase-9 (MMP-9), and cardiac Troponin-T (cTnT) were evaluated by appropriate biochemical methods. RESULTS: Measurements made on the histological and microcomputed tomographic slices showed that melatonin significantly limits the ligature-induced periodontal tissue destruction (P <0.01). In addition, melatonin was detected to cause a significant decrease of MDA, MMP-9, and cTnT levels which were found to be significantly higher on rats with Ep (P <0.05) while having no significant effect on antioxidant levels (GSH, SOD, and CAT) (P >0.05). CONCLUSION: Melatonin might be regarded as an important supportive therapeutic agent to reduce the early degenerative changes and possible hypertrophic remodeling at cardiac left ventricular tissues provoked by periodontitis-related bacteria and/or periodontal inflammation.

Nicotine reduces effectiveness of doxorubicin chemotherapy and promotes CD44+CD24- cancer stem cells in MCF-7 cell populations.

Breast cancer is the most common type of cancer in females and the second most common cause of cancer mortality after lung cancer. Cancer stem cells represent a novel approach to target cancer and reduce cancer recurrence and metastasis. Many patients with breast cancer continue to smoke after receiving their diagnosis. Nicotine is a key factor in tobacco addiction and also changes some cellular functions, such as activation of mitogenic pathways, angiogenesis and cell proliferation. In the present study, the impact of nicotine was assessed in a population of MCF-7 human breast cancer cells. Cluster of differentiation (CD)44+CD24- cancer stem cell population of MCF-7 cells were evaluated using flow cytometry and scanning electron microscopy. Chemoresistance effects of nicotine were demonstrated in these cells. These findings demonstrated harmful effects of nicotine following metastasis of cancer, owing to the chemoresistance produced through uninterrupted smoking, which may impact the effectiveness of treatment.

iCELLigence real-time cell analysis system for examining the cytotoxicity of drugs to cancer cell lines.

The recently developed iCELLigence™ real-time cell analyzer (RTCA) can be used for the label-free real-time monitoring of cancer cell proliferation, viability, invasion and cytotoxicity. The RTCA system uses 16-well microtiter plates with a gold microelectrode biosensor array that measures impedance when cells adhere to the microelectrodes causing an alternating current. By measuring the electric field generated in this process, the RTCA system can be used for the analysis of cell proliferation, viability, morphology and migration. The present review aimed to summarize the working method of the RTCA system, in addition to discussing the research performed using the system for various applications, including cancer drug discovery via measuring cytotoxicity.

Isolation of hematopoietic stem cells and the effect of CD38 expression during the early erythroid progenitor cell development process.

The aim of this study was to investigate changes in primitive hematopoietic cells through CD38 expression, identify the stage at which erythrocyte differentiation CD38 gains activity and the effects of serum factors on this expression by establishing a hematopoietic stem cell system in the erythroid development process. Using an immunomagnetic labeling and separation technique, CD34(+) cells were selected from cord blood. The CD34(+) cells were cultured in a 2 mM L-glutamine-enriched medium containing erythropoietin (Epo), penicillin-streptomycin and stem cell factor (SCF), and were incubated in 5% CO(2) at 37°C. In erythroid development pathways following CD38 expression, primitive/progenitor human hematopoietic cells obtained from cord blood were assessed through the erythroid development process in a serum-free medium in the presence of proper SCF and Epo. At the end of the 26-day process, using staining with a Megacult-c staining kit, it was determined that progenitor cells nucleate and differentiate into erythroid cell lines of 8-10 µm. During the course of this process, we analyzed increases over time in NAD glycohydrolase activity rates using the supernatant liquid samples. Results of co-culture experiments in cell culture studies showed that the stimulating effects of CD38 expression originate from specific serum factors. CD38 expression has been shown to occur at hematopoietic cell sources as well as at a number of differentiation levels. In the proliferation process the possible induction of CD38 through specific serum factors leads us to conclude that it may be involved in proliferation with a physiological task or that it may be involved in an event, such as an apoptotic process.

CD38 expression as response of hematopoietic system to cancer.

Erythrocyte and lymphocyte NAD(+) glycohydrolase levels were previously found to be elevated in cancer patients. These results were confirmed in an animal model. The administration of live Ehrlich ascites tumor cells to BALB/c mice led to increases in erythrocyte and lymphocyte NAD(+) glycohydrolase, along with tumor development. Serum samples, ascites fluid from mice with developed tumors, serum samples from cancer patients and Ehrlich cell supernatants had a similar stimulatory effect when administered to mice or when incubated with peripheric lymphocytes in culture. These increases were accompanied by the appearance of an anti-CD38 reactive band of 45 kDa in SDS-PAGE/Western blot analyses of erythrocyte ghost and lymphocyte membrane proteins. The results, supported by flow cytometry data, support previous clinical findings that an enhancement in CD38 expression occurs in the hematopoietic system during proliferative processes. Moreover, they suggest that CD38 expression is triggered at least in part by a certain cytokine(s) secreted by cancer cells. Finally, the results emphasize the prospective use of CD38 expression as a marker of tumor development and progression.

Erythrocyte CD38 as a prognostic marker in cancer.

BACKGROUND: Surface antigen CD38 which is a multifunctional protein with enzymatic and receptorial properties is involved in many processes of cell proliferation and activation. It is widely expressed within the hematopoetic system, and its expression is stimulated by proinflammatory cytokines. CD38-associated enzymatic activities in erythrocytes from cancer patients were investigated in this context. METHODS: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities in normal individuals and cancer patients were compared and correlation of these activities to CEA values and anemia were determined. Changes in CD38-expression were followed by SDS-PAGE and Western blot analysis of erythrocyte membrane proteins. RESULTS: Erythrocyte NAD glycohydrolase and ADP-ribosyl cyclase activities were significantly increased in cancer, in parallel to enhancement of CD38 expression and in correlation with CEA values and anemia. CONCLUSIONS: An increased expression of CD38 which may be due to action of proinflammatory cytokines produced in tumor-host reactions appears to account for the elevations in erythrocyte CD38-associated enzyme activities in cancer patients. The changes in these enzyme activities may provide a prognostic outlook in view of their apparently close correlation to tumor progressions.