Altered DNA methylation and Dnmt expression in obese uterus may cause implantation failure.

Obesity is defined by increased adipose tissue volume and has become a major risk factor for reproduction. Recent studies have revealed a substantial link between obesity and epigenetics. The epigenome is dynamically regulated mainly by DNA methylation. DNA methylation, which is controlled by DNA methyltransferases (Dnmts), has been widely studied because it is essential for imprinting and regulation of gene expression. In our previous study, we showed that the levels of Dnmt1, Dnmt3a and global DNA methylation was dramatically altered in the testis and ovary of high-fat diet (HFD)-induced obese mice. However, the effect of HFD on Dnmts and global DNA methylation in mouse uterus has not yet been demonstrated. Therefore, in the present study, we aimed to evaluate the effect of HFD on the level of Dnmt1, Dnmt3a, Dnmt3b, Dnmt3l and global DNA methylation in uterus. Our results showed that HFD significantly altered the levels of Dnmts and global DNA methylation in the uterus. The total expression of Dnmt1, Dnmt3a and Dnmt3b was significantly upregulated, while level of Dnmt3l and global DNA methylation were dramatically decreased (p < 0.05). Furthermore, we observed that the expression of Dnmt3b and Dnmt3l was significantly increased in endometrium including gland and epithelium (p < 0.05). Although Dnmt3b was the only protein whose expression significantly increased, the level of global DNA methylation and Dnmt3l significantly decreased in stroma and myometrium (p < 0.05). In conclusion, our results show for the first time that obesity dramatically alters global DNA methylation and expression of Dnmts, and decreased DNA methylation and Dnmt expression may cause abnormal gene expression, especially in the endometrium.

Dual action of exosomes derived from in vitro Aß toxicity model: The role of age for pathological response.

Exosomes released from different cell types of the central nervous system play an essential role in the pathogenesis of Alzheimer's disease (AD). In this study, we aimed to create an animal model by injecting exosomes that carry AD markers into the brain to shed light on the mechanism behind Alzheimer's pathology. Exosomes obtained from mouse Neuro2A, to which Aß toxicity model applied, were used as a mediator to build an AD phenotype. For this purpose, exosomes were administered into hippocampal CA3 region of mice with different ages. Firstly, the possible role of exosomes on brain volume was analyzed. Then, neurons and astrocytes were evaluated for survival. In addition, the progenitor cells' differentiation capacity was investigated via BrdU staining. AKT signaling pathway components were examined to detect the molecular mechanisms behind the exosomal function. We found different responses in different age groups. Expression of APP upregulated only in young animals upon delivery of Aß-exosomes. Interestingly, young animals represented increased numbers of neurons in the hippocampus, and neurogenesis was found to be restricted after Aß-Ex injections. However, in relation to exosome administration, the glial intensity increased in aged animals. Lastly, phosphorylation of survival kinase AKT was downregulated due to the presence of Aß in both young and old animals. The findings reveal that the exosomes from an in vitro Aß toxicity model may induce different responses in an age-dependent manner. This study is the first to report the relationship between exosomal function and aging by evaluating the key molecules.

Two boron-containing compounds affect the cellular viability of SH-SY5Y cells in an in vitro amyloid-beta toxicity model.

Boron is a naturally occurring trace element found in organic and inorganic complexes. Boron-containing compounds are required for living organisms for diverse metabolic functions, including nitrogen fixation in microorganisms, cell wall stability in plants, and bone and carbohydrate metabolism in animals. The number of studies about the effect of boron in biological model systems is very limited; so far, there has been no study on the correlation between boron and amyloid-beta toxicity. Here, we investigated the possible effects of 2 boron-containing compounds-sodium borate decahydrate and boric acid-against amyloid-beta toxicity. In our in vitro amyloid-beta toxicity model, we showed that these 2 compounds increase the survival of the SH-SY5Y cells. Furthermore, boron in these 2 forms increases the expression of Sirt1, which has protective functions against cellular stress. The compounds also change the expressions of GSK-3α/ß; by doing so, boron may contribute to the stimulation of intracellular prosurvival pathways. This is the first experimental study indicating the prosurvival effect of boron in an amyloid-beta toxicity model.

Neuroprotective effects of hemicraniectomy in malignant middle cerebral artery infarctions: experimental study.

BACKGROUND: Despite optimal medical therapy the mortality rate approaches 50% in MCA infarctions. Although recent studies have been showed life-saving effect of hemicraniectomy; there are a few data available in regard to neuroprotection effect of decompressive craniectomy (DC). We induced a malignant cerebral ischemia model by intraluminal permanent middle cerebral artery occlusion (MCAo) in male rats for defining the neuroprotective effects of early DC on brain-blood barrier (BBB) molecular changes, infarct size and cerebral edema. METHODS: A total of 48 male Spraque-Dawley rats were allocated to 4 groups; sham (N.=9), control (N.=9), experiment 1 (N.=15), experiment 2 (N.=15). DC was performed by creating a bone flap, after MCAo at 4 and 24 hours. After 28 hours of survival, all animals were sacrificed. Infarction volumes were calculated from TTC (2,3,5-triphenyl-2H-tetrazolium chloride)-stained brain sections. In all groups, cerebral edema was quantified as a change in the percentage of brain water content. Western Blot was used to analyze the expression of tight junction protein claudin-5 and occludin. RESULTS: Brain water content was calculated 75.18±0.75% in the early DC group and 77.76±0.71% in the late DC group. No significant difference was found between experiment groups (P=0.178). In the early DC group; occludin and claudin-5 were significantly expressed at higher levels compared to late DC group (occluding, P=0.013; claudin-5, P=0.034). At early DC group (73.38±23.11 mm3) the final infarct volumes were significantly smaller than in the late DC group (377.18±39.23 mm3) (P=0.013). CONCLUSIONS: The study results supported the neuroprotective effects of early DC in malignant MCA infarcts.

Neuroprotective Effects of Chronic Fenofibrate Treatment via Modulating the Immunoreactivity of Cleaved Caspase-3 in Stroke Induced by Transient Middle Cerebral Artery Occlusion Rat Model.

AIM: Current stroke therapies include lipid-lowering drugs, which reduce inflammation and serve to stabilize the atherosclerotic plaque to demonstrate better outcome and neuroprotection. Peroxisome proliferator activated receptors (PPAR) ? regulates lipid homeostasis and is a target of fibrates, which have a neuroprotective function by various mechanisms. In this study, we aimed to evaluate the role of the PPAR? agonist, fenofibrate, in the modulation of cleaved caspase-3 immunoreactivity and at the final infarct volume in an experimental ischemia/reperfusion rat model by induced transient proximal middle cerebral artery occlusion. MATERIAL AND METHODS: A total of 65 male Sprague Dawley rats were allocated into 4 groups; sham (n =5), experiment 1 (n=20), experiment 2 (n=20), experiment 3 (n=20). All experiment groups were divided to 3 subgroups in order to evaluate the final infarct volume at 24th hour (n=5) and the immunoreactivity of cleaved caspase -3 at different time periods [at first hour (n=5), at 6th hour (n=5), at 24th hour (n=5)] after transient middle cerebral artery occlusion (MCAo). At the study, the experiment groups (Experiment 1 and Experiment 2) were received the fenofibrate-diet during 14 days before ischemia procedure. All animals were sacrificed at 24th hours after MCAo. Infarction volumes were calculated from 2,3,5,triphenyltetrozolium chloride (TTC)- stained brain sections. RESULTS: We found that fenofibrate-therapy reduced significantly more body weight than the other experiment groups (p < 0.05). At the time intervals, a decrease of immunoreactivity of cleaved caspase-3 was significantly observed with fenofibrate therapy after MCAo (p < 0.05). Chronic fenofibrate treatment before cerebral ischemia significantly reduced the infarction size after MCAo compared with the other groups (respectively; p = 0.011 and p < 0.000). CONCLUSION: Fenofibrate treatment has neuroprotective effects on middle cerebral artery infarcts.

The relationship of platelet-to-lymphocyte ratio with clinical outcome and final infarct core in acute ischemic stroke patients who have undergone endovascular therapy.

OBJECTIVES: Of all strokes, 85% are ischemic and intracranial artery occlusion accounts for 80% of these ischemic strokes. Endovascular therapy for acute ischemic stroke was a new modality aiming at resolution of clots in occluded cerebral arteries. The platelet-to-lymphocyte ratio (PLR) was introduced as a potential marker to determine increased inflammation, which is a result of releasing many mediators from the platelets. In this study we aimed to evaluate whether the PLR had a prognostic role in stroke patients undergoing thrombectomy and attempted to determine the effect that this ratio had on their survival. METHODS: Over a three-year period, demographic, clinical, and angiographic findings of 57 consecutive patients with acute ischemic stroke who underwent mechanical thrombectomy were evaluated. RESULTS: The patients were divided into two groups on the basis of a PLR level cut-off value of 145 based on receiver operating characteristic (ROC) curve. Successful revascularization (mTICI 2b and 3) was achieved in 42 of 57 (73.7%) patients; a mTICI 3 state was observed in 21 of 23 patients with low-PLR values (p = .015). Patients with higher PLR values had significantly a score of less than six on the ASPECT scale compared to patients with lower PLR values (p = .005). The patients with low-PLR values had better functional outcomes (mRS ≤ 2) compared with the patients with high-PLR values [respectively, p = .004 (at first month) and p = .014 (at third month)]. DISCUSSION: The platelet-to-lymphocyte ratio could represent pro-thrombotic inflammatory state in acute ischemic stroke patients because having a high-PLR values increased the poor prognosis, the rate of insufficient recanalization, and the size of infarcted area.