title: Evaluation of the relationship between serum apelin levels and vitamin D and mean platelet volume in diabetic patients.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: dr_kiskac@mynet.com.
authors.forename: Muharrem
authors.initials: M
authors.lastname: Kiskac
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: drmehmetzorlu@mynet.com.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Zorlu
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: drcakirca@yahoo.de.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Cakirca
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: ckaratoprak@hotmail.com.
authors.forename: Cumali
authors.initials: C
authors.lastname: Karatoprak
authors.affiliation: Department of Biochemisty, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: sdkakesgin@gmail.com.
authors.forename: Sıdıka
authors.initials: S
authors.lastname: Kesgin
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: bbuyukaydin@hotmail.com.
authors.forename: Banu
authors.initials: B
authors.lastname: Büyükaydın
authors.affiliation: Family Care Center Rize, Turkey. Electronic address: erdincyavuz@gmail.com.
authors.forename: Erdinc
authors.initials: E
authors.lastname: Yavuz
authors.affiliation: Family Care Center Rize, Turkey. Electronic address: drcuneytardic@hotmail.com.
authors.forename: Cuneyt
authors.initials: C
authors.lastname: Ardic
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: adilcamli@gmail.com.
authors.forename: Ahmet Adil
authors.initials: AA
authors.lastname: Camli
authors.affiliation: Internal Medicine Clinic, Bezmialem Vakif University, Faculty of Medicine, 34093 Fatih, Istanbul, Turkey. Electronic address: malicikrikcioglu@yahoo.com.
authors.forename: Mehmet Ali
authors.initials: MA
authors.lastname: Cikrikcioglu
mesh_terms: D000886:Anthropometry; D000073861:Apelin; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D006801:Humans; D006887:Hydroxycholecalciferols / Q000097:blood; D007333:Insulin Resistance; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008297:Male; D024821:Metabolic Syndrome / Q000378:metabolism; D008875:Middle Aged; D010976:Platelet Count; D014807:Vitamin D / Q000097:blood*
chemical_list: C115436:APLN protein, human; D000073861:Apelin; D006887:Hydroxycholecalciferols; D036341:Intercellular Signaling Peptides and Proteins; D014807:Vitamin D
keywords: Apelin; Apéline; Diabetes mellitus; Diabète sucré; MPV; VMP; Vitamin D; Vitamine D