title: Ramadan fasting in Saudi Arabia is associated with altered expression of CLOCK, DUSP and IL-1alpha genes, as well as changes in cardiometabolic risk factors.
abstract: BACKGROUND
  During the fasting month of Ramadan, practicing Saudis develop severe disturbances in sleeping and feeding patterns. Concomitantly, cortisol circadian rhythm is abolished, diurnal cortisol levels are elevated and circulating levels of several adipokines are altered favouring insulin resistance.
  
  
  OBJECTIVE
  To examine changes in the expression of CLOCK and glucocorticoid-controlled genes, such as DUSP1 and IL-1α in Saudi adults before and during Ramadan, and to investigate possible associations with selected cardiometabolic risk factors.
  
  
  METHODS
  Healthy young volunteers (5 females, 18 males; mean age +SEM = 23.2 +1.2 years) were evaluated before Ramadan and two weeks into it. Blood samples were collected at 9 am (±1 hour) and twelve hours later for determination of serum lipid profile, high sensitivity CRP (hsCRP), and adiponectin. The expression of CLOCK, DUSP1 and IL-1α was evaluated in circulating leukocytes.
  
  
  RESULTS
  Mean levels of GGT and morning adiponectin decreased, while those of LDL-c/ HDL-c and atherogenic index (AI) increased significantly in Ramadan compared to Shabaan. There was no significant difference between morning and evening adiponectin during Ramadan, while the diurnal rhythm of hsCRP was lost. CLOCK gene expression mean was significantly higher in morning than in evening during Shabaan. Mean morning and evening DUSP1 mRNA levels showed significant increase during Ramadan compared to Shabaan, however, its diurnal rhythm was maintained. Morning IL-1α mRNA expression remained significantly higher than in the evening during Ramadan, but was markedly decreased compared to Shabaan.
  
  
  CONCLUSIONS
  Ramadan fasting in Saudi Arabia is associated with improvements in some cardiometabolic risk factors, such as circulating GGT and hsCRP and leukocyte expression of IL-1α mRNA, suggesting that intermittent fasting might have a beneficial component. These benefits may be offset by the previously reported dysregulation in the circadian rhythm, excess glucocorticoid levels and action, and insulin resistance, explaining increased prevalence of cardiometabolic disorders and type 2 diabetes mellitus.
authors.affiliation: Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.|Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Ghada M A
authors.initials: GM
authors.lastname: Ajabnoor
authors.affiliation: Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.|Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Suhad
authors.identifier: http://orcid.org/0000-0001-6674-5409
authors.initials: S
authors.lastname: Bahijri
authors.affiliation: Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.|Princess Al-Jawhara Al-Brahim Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Noor Ahmad
authors.initials: NA
authors.lastname: Shaik
authors.affiliation: Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.|King Abdullah International Medical Research Center (KAIMRC), College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Jeddah, Saudi Arabia.
authors.forename: Anwar
authors.initials: A
authors.lastname: Borai
authors.affiliation: Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.|Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Aliaa A
authors.initials: AA
authors.lastname: Alamoudi
authors.affiliation: Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.|Department of Genetic Medicine, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia.|Princess Al-Jawhara Al-Brahim Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Jumana Y
authors.initials: JY
authors.lastname: Al-Aama
authors.affiliation: Saudi Diabetes Study Research Group, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia.|First Department of Pediatrics, University of Athens Medical School,''Aghia Sophia" Children's Hospital, Athens, Greece.
authors.forename: George P
authors.initials: GP
authors.lastname: Chrousos
mesh_terms: D056926:CLOCK Proteins / Q000378:metabolism*; D002319:Cardiovascular System / Q000378:metabolism*; D054637:Dual-Specificity Phosphatases / Q000378:metabolism*; D005215:Fasting; D006801:Humans; D053582:Interleukin-1alpha / Q000378:metabolism*; D007514:Islam; D054639:Mitogen-Activated Protein Kinase Phosphatases / Q000378:metabolism*; D012529:Saudi Arabia
chemical_list: D053582:Interleukin-1alpha; D056926:CLOCK Proteins; C538943:CLOCK protein, human; D054639:Mitogen-Activated Protein Kinase Phosphatases; D054637:Dual-Specificity Phosphatases