Folate and Cobalamin Serum Levels in Healthy Children and Adolescents and Their Association with Age,Sex, BMI and Socioeconomic Status

This study proposes age- and sex-specific percentiles for serum cobalamin and folate, and analyzes the effects of sex, age, body mass index (BMI), and socioeconomic status (SES) on cobalamin and folate concentrations in healthy children and adolescents. In total, 4478 serum samples provided by healthy participants (2 months–18.0 years) in the LIFE (Leipzig Research Centre for Civilization Diseases) Child population-based cohort study between 2011 and 2015 were analyzed by electrochemiluminescence immunoassay (ECLIA). Continuous age-and sex-related percentiles (2.5th, 10th, 50th, 90th, 97.5th) were estimated, applying Cole’s LMS method. In both sexes, folate concentrations decreased continuously with age, whereas cobalamin concentration peaked between three and seven years of age and declined thereafter. Female sex was associated with higher concentrations of both vitamins in 13- to 18-year-olds and with higher folate levels in one- to five-year-olds. BMI was inversely correlated with concentrations of both vitamins, whilst SES positively affected folate but not cobalamin concentrations. To conclude, in the assessment of cobalamin and folate status, the age- and sex-dependent dynamic of the respective serum concentrations must be considered. While BMI is a determinant of both vitamin concentrations, SES is only associated with folate concentrations.     

Skeletal muscle ischemia–reperfusion injury and cyclosporine A in the aging rat

Old patients exhibit muscle impairments and increased perioperative risk during vascular surgery procedures. Although aging generally impairs protective mechanisms, data are lacking concerning skeletal muscle in elderly. We tested whether cyclosporine A (CsA), which protects skeletal muscle from ischemia–reperfusion (IR) in young rats, might reduce skeletal muscle mitochondrial dysfunction and oxidative stress in aging rats submitted to hindlimb IR. Wistar rats aged 71–73 weeks were randomized to IR (3 h unilateral tourniquet application and 2 h reperfusion) or IR + CsA (10 mg/kg cyclosporine IV before reperfusion). Maximal oxidative capacity (V_Max), acceptor control ratio (ACR), and relative contribution of the mitochondrial respiratory chain complexes II, III, IV (V_Succ), and IV (V_TMPD/Asc), together with calcium retention capacity (CRC) a marker of apoptosis, and tissue reactive oxygen species (ROS) production were determined in gastrocnemius muscles from both hindlimbs. Compared to the nonischemic hindlimb, IR significantly reduced mitochondrial coupling, V_Max (from 7.34 ± 1.50 to 2.87 ± 1.22 μMO₂/min/g; P < 0.05; ?70%), and V_Succ (from 6.14 ± 1.07 to 3.82 ± 0.83 μMO₂/min/g; P < 0.05; ?42%) but not V_TMPD/_Asc. IR also decreased the CRC from 15.58 ± 3.85 to 6.19 ± 0.86 μMCa²⁺/min/g; P < 0.05; ?42%). These alterations were not corrected by CsA (?77%, ?49%, and ?32% after IR for V_Max, V_Succ, and CRC, respectively). Further, CsA significantly increased ROS production in both hindlimbs (P < 0.05; +73%). In old rats, hindlimb IR impairs skeletal muscle mitochondrial function and increases oxidative stress. Cyclosporine A did not show protective effects.