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.

Evaluation of the relationship between serum apelin levels and vitamin D and mean platelet volume in diabetic patients.

OBJECTIVES: It was reported that Vitamin D deficiency was associated with a greater risk of cardiometabolic diseases, obesity, impaired glucose tolerance and diabetes mellitus type 2, arterial hypertension, and dyslipidemia. Apelin is an adipocytokine suspected to have a role in skeletal muscle glucose utilization and glycemic regulation which may be a promising treatment modality for diabetes. It was recently reported that increased mean platelet volume (MPV) was emerging as an independent risk factor for thromboembolism, stroke, and myocardial infarction. In patients with diabetes, MPV was higher compared with the normal glycemic controls; in addition, it has been proposed that an increase in MPV may play a role in the micro- and macro-vascular complications related to diabetes. We postulated that deficiency in Vitamin D levels might be associated with higher MPV and lower serum apelin levels leading a further increase in insulin resistance in diabetic patients. So, we aimed to investigate Vitamin D levels, MPV and serum apelin levels in diabetic patients and their correlations between each other. MATERIALS AND METHOD: This is a cross-sectional study design. Seventy-eight patients with Diabetes Mellitus type 2, admitted to our outpatient clinic of internal medicine department at Bezmialem Vakif University, were included in our study. Forty-one patients were female; 37 patients were male. Serum apelin levels, fasting glucose levels, urea, creatinine, triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting serum insulin level, HbA1c, free T3, free T4, TSH, vitamin D (25-OH Vitamin D) and complete blood counts were analyzed in all subjects. RESULTS: Each sex was analyzed separately. We found that a positive correlation existed between serum apelin levels and BMI in female patients. (r: 0.380, P: 0.014) There was also a significant positive correlation between MPV and HbA1c and fasting glucose levels and a negative correlation between MPV and PLT. (r: 0.377, P: 0.021; r: 0.395, P: 0.014; r: -0.401, P: 0.011; respectively) We failed to show a significant relationship between serum vitamin D levels, serum apelin levels and MPV in patients with diabetes mellitus type 2. CONCLUSION: We failed to show an association between vitamin D, apelin and MPV higher volumes of which may have a role in cardiovascular complications related to diabetes by increasing platelet activation.

Assessment of serum apelin and lipocalin-2 levels in patients with subclinical hypothyroidism.

OBJECTIVES: Subclinical hypothyroidism is the precursor to hypothyroidism because it has a tendency to transform into hypothyroidism. Subclinical hypothyroidism is considered one of the risk factors causing metabolic syndrome. Metabolic syndrome can be characterized by plasma levels of apelin and lipocalin-2, both released from adipocytes. In the present study, we aimed to measure serum apelin and lipocalin-2 levels of patients with subclinical hypothyroidism and compare them with serum apelin and lipocalin-2 levels from healthy individuals. METHODS: This was a cross-sectional study. A total of 80 subjects were enrolled in the study and divided into two groups: Group A included 39 patients (females, n=34) diagnosed with subclinical hypothyroidism, and Group B (the control group) comprised 41 healthy volunteers (females, n=38). Serum samples were obtained from each participant for the measurement of apelin and lipocalin-2. These were then stored at minus 80°C until the time of analysis, when serum apelin and lipocalin-2 levels of the two groups were compared. RESULTS: Patients with subclinical hypothyroidism (Group A and Group B subjects [healthy controls]) were comparable with respect to gender, age, and body mass index (BMI) (P=0.412, P=0.863, and P=0.269, respectively), nor was there a statistically significant difference between groups in terms of apelin and lipocalin-2 levels (P=0.87, and P=0.67, respectively). Apelin levels showed a positive and significant correlation with BMI (P=0.034). Serum lipocalin-2 levels showed significant positive correlations with BMI and creatinine levels (P=0.002, and P=0.025, respectively). CONCLUSION: In the present study, no significant difference of serum apelin and lipocalin-2 levels was observed between patients with subclinical hypothyroidism and healthy control subjects. Positive correlations were found, however, between serum apelin level and BMI as well as between serum lipocalin-2 and BMI and creatinine levels.