Diet and Lifestyle Role in Homocysteine Metabolism in Turner Syndrome.

OBJECTIVE: Patients with Turner syndrome (TS) have an unfavorable cardiometabolic profile. Hyperhomocysteinemia is a potential cardiovascular risk factor influenced by genetic and environmental factors, therapies, unbalanced diets and other lifestyle factors. We retrospectively studied the relationship between total plasma homocysteine (Hcy), serum vitamin B12 (B12) and folate concentration in TS patients, taking into account the genetic profile, diet, smoking habits, hormonal therapies and dietary supplements of the subjects. PATIENTS AND METHODS: We evaluated 50 TS patients (31.5 ± 12.5 years). Medication, including vitamin supplementation, was obtained. Eating habits, cigarette smoking, alcohol and coffee consumption were investigated using phone interviews. Levels of Hcy metabolism parameters were classified by using the relevant cutoff value for an adult population and compared with a reference sample drawn from the general population. RESULTS: Inadequate Hcy and B12 levels were noted, despite vitamin supplementation. Holotranscobalamin (HoloTC) was above the relevant cutoff in the population, and supplemented subjects showed mean levels lower than nonsupplemented subjects (p = 0.005). Dietary supplementation (p = 0.038), lifestyle (coffee consumption, p = 0.01) and hormonal replacement therapy (p = 0.02) are important factors for Hcy metabolism. No genetic influence on Hcy levels was noted. Multivariable regression analysis identified vitamin supplementation (p = 0.045) as the only independent predictor of increased Hcy levels. CONCLUSION: Cardiovascular risk in TS can be reduced using educational approaches to a healthy lifestyle with dietary guidelines. Besides this, we also recommend measuring HoloTC for the prompt detection of B12 deficiency and to consider hormone replacement therapy in the biochemical assessment of homocysteine in TS.

MKRN3 and KISS1R mutations in precocious and early puberty.

BACKGROUND: Pubertal timing is known to be influenced by interactions among various genetic, nutritional, environmental and socio-economic factors, although the ultimate mechanisms underlying the increase in pulsatile GnRH secretion at puberty have yet to be fully elucidated. The aim of our research was to verify the role of KISSR1 (previously named GPR54) and MKRN3 genes on pubertal timing. METHODS: We analyzed the DNA sequence of these genes in 13 girls affected by central precocious puberty (CPP) who showed onset of puberty before 8 years of age, and in 6 girls affected by early puberty (EP) between 8 and 10 years of age. RESULTS: Direct sequencing of the KISS1R (GPR54) gene revealed two SNPs. One SNP is a missense variant (rs 350,132) that has been previously reported in connection to CPP in Korean girls. The other variant that we found in the GPR54 gene (rs764046557) was a missense SNP located in exon 5 at position 209 of the aminoacid. We identified this variant in only one CPP patient. Automatic sequencing of MKRN3 in all patients revealed three variants in eight subjects. In 6 out of 19 (31.5%) patients (3/13 CPP patients and 3/6 EP patients) we found the synonymous variant c.663C > T (rs2239669). Another synonymous variant (rs140467331) was found in one of our CPP patients, as well as one missense variant (rs760981395) in another CPP patient. CONCLUSION: In conclusion, we identified sequence variations of the KISS1R and MKRN3 genes, two of the most frequent genetic causes of ICPP. Our results suggest that these variants might be inducible factors in the pathogenesis of CPP.

Rapid progressive central precocious puberty: diagnostic and predictive value of basal sex hormone levels and pelvic ultrasound.

Objectives Data on the predictive values of parameters included in the diagnostic work-up for precocious puberty (PP) remain limited. We detected the diagnostic value of basal sex hormone levels, pelvic ultrasound parameters and bone age assessment for activation of the hypothalamic-pituitary-gonadal axis in girls with PP, in order to help in the decision to perform GnRH testing. Patients and methods We retrospectively considered 177 girls with PP. According to puberty evolution, the girls were divided into two groups: rapid progressive central precocious puberty (RP-CPP) and non/slowly progressive/transient forms (SP-PP). In all patients we considered Tanner stage, basal luteinizing hormone (LH) and estradiol (E2) values, bone age, and pelvis examination. We assessed the diagnostic value of each variable and identified the number of pathological parameters that best identify patients with RP-CPP. Results Basal LH ≥ 0.2IU/L, E2 level ≥ 50 pmol/L, uterine longitudinal diameter ≥ 3.5 cm, transverse uterine diameter ≥ 1.5 cm, endometrial echo and ovarian volume ≥ 2 cm3 were significantly associated with RP-CPP (p ≤ 0.01). The ability to diagnose RP-CPP was enhanced with increasing number of pathological hormonal and instrumental parameters (p < 0.001). With more than three parameters detected, sensitivity and specificity reached 58% (95%CI 48-67) and 85% (95%CI 74-92), respectively, with a PPV = 86% (95%CI 76-93) and PPN = 54% (95%CI 43-54); the area under the ROC curve was 0.71 (95%CI 0.65-0.78). Conclusion Despite the availability of different tests, diagnosing RP-CPP remains difficult. A diagnosis model including at least three hormonal and/or ultrasound parameters may serve as a useful preliminary step in selecting patients who require GnRH testing for early detection of RC-PP.

Gender-based differences in the clustering of metabolic syndrome factors in children and adolescents.

Background We depicted gender-differences in metabolic syndrome (MS) clustering before and after puberty in pediatrics, in order to develop gender specific preventive strategies for childhood obesity. Methods We considered 1079 children and adolescents (529 females and 550 males; mean age 11.5 ± 2.8 year). According to body mass index (BMI) percentiles the subjects were classified as normal weight BMI <75th, overweight BMI 75-95th and with obesity BMI >95th. MS was diagnosed when three of the following criteria for age and sex percentiles were met: BMI >95th, triglycerides (TGs) level >95th, high-density lipoprotein-cholesterol (HDL-c) level <5th, blood pressure (blood pressure) >95th percentile, fasting blood glucose (FBG) >100 mg/dL and/or homeostatic model assessment- insulin resistance (HOMA-IR) >97.5th percentile. Results The prevalence of dismetabolic factors was similar in both genders, except for pathological BP, which was higher in males (p = 0.02). MS was detected only in patients with obesity, with a higher prevalence in pubertal than late/post-pubertal subjects (p < 0.001), without any significant difference between gender. In pre-puberty, the most common MS combination was obesity (HBMI) + hypertension (HBP) + hyperglycemia/insulin resistance (HGLY/IR) followed by HBMI + low HDL-levels (LHDL) + HGLY/IR versus HBMI + HBP + HGLY/IR followed by HBMI + HBP + LHDL, respectively, in females and males. In the early and late/post-pubertal periods, the most prevalent combination remained similar to pre-puberty, additionally in both sexes other combinations, such as HBMI + HTG + HBP + HGLY/IR, HBMI + HBP + LHDL + HGLY/IR, HBMI + HTG + LHDL + HGLY/IR and HBMI + HTG + LHDL + HBP + HGLY/IR were also detected, differently distributed in males and females. Conclusions We confirm that MS is an important consequence related to obesity, particularly in the post-puberty stage. Some gender-based differences should be considered early in order to identify specific preventive and treatment strategies.

Autoimmune Thyroid Diseases in Children and Adolescents with Maturity Onset Diabetes of the Young Type 2.

BACKGROUND/AIM: The relationship between type 1 diabetes mellitus (T1DM) and autoimmune thyropathies is well known and has been described in the literature. Based on present knowledge, the relationship between thyropathies and other forms of diabetes, such as monogenic diabetes, has not been investigated. The aim of our study was to assess the prevalence of autoimmune thyroid diseases (ATD) in children and adolescents with maturity onset diabetes of the young type 2 (MODY2) in comparison with patients with T1DM and a control group. PATIENTS AND METHODS: We examined 23 children and adolescents with MODY2 (11 F/12 M; 13.5 ± 5.3 years) and 166 patients with T1DM (80 F/86 M; 14.0 ± 4.7 years). The control group consisted of 62 age-matched healthy subjects (34 F/28 M). ATD diagnosis was based on the finding of one or more positive thyroid autoantibodies and characteristic thyroid ultrasound lacking homogeneity, with a hypogenic or mixed echo pattern. RESULTS: ATD was diagnosed in 15 (10.5%; 9 F/6 M) patients with T1DM, in 4 with MODY2 (17.4%; 4 F), and in 1 (1.6%) control. A significantly higher ATD prevalence was detected in T1DM and MODY2 compared to the control subjects (p = 0.02), without differences between T1DM and MODY2 (p = 0.26). There were no gender differences noted in T1DM (p = 0.42); on the contrary, in MODY2 a higher prevalence was noted in females (p = 0.04). Celiac disease and a positive family history of ATD were not detected in subjects with MODY2. CONCLUSION: Our study showed an increased prevalence of ATD in patients with MODY2. Therefore, a careful follow-up of all children with MODY2 is recommended in order to assess the presence of thyroid disorders.

Evaluation of Allostatic Load as a Marker of Chronic Stress in Children and the Importance of Excess Weight.

Introduction: Allostatic load (AL) refers to the physiological response associated with the burden of chronic stress. Excessive weight is an important source of physiological stress that promotes a detrimental chronic low-inflammation state. In order to define a correlation between cumulative biological dysregulation and excess weight, we measured AL scores in a pediatric population. Patients and Methods: We enrolled 164 children and adolescents (11.89 ± 3.89). According to their body mass index (BMI) threshold, subjects were classified as normal in the BMI < 75th percentile, overweight in the BMI 75-95th percentile or obese in the BMI >95th percentile. Data based on 16 biomarkers were used to create the AL score. A dichotomous outcome for high AL was defined in those who had more than four dysregulated components. Results: High AL was noted in 88/164 subjects (53.65%), without significant differences between genders (p = 0.07) or pubertal status (p = 0.10). Subjects with a high AL, in addition to a higher BMI (p < 0.001), showed higher WC and WC/HtR (p < 0.001), triglycerides (p = 0.002), fasting blood glucose (p = 0.03), insulin resistance (p < 0.001), systolic (p < 0.001) and diastolic blood pressure (p = 0.001), GGT (p = 0.01), PCR (p = 0.01), and calprotectin (p < 0.01) as well as lower HDL cholesterol (p = 0.002) than subjects with a low AL. The rate of the cumulative biological dysregulation increased progressively with increases in BMI (p < 0.001). Conclusions: A high AL was associated with excess weight. AL may be considered a significant factor correlated with increased morbidity in children who are overweight/obese.

Triglyceride Glucose Index as a Surrogate Measure of Insulin Sensitivity in a Caucasian Pediatric Population

Objective: The triglyceride and glucose (TyG) index has been proposed as a simple surrogate of insulin resistance (IR) with high sensitivity as an IR index besides the well known homeostasis model assessment of IR (HOMA-IR). Limited data are reported in children. We investigated the sensitivity and specificity of TyG index in a pediatric Caucasian population, as a surrogate measure of IR and compared the results with HOMA-IR. Methods: We enrolled 541 children (11.7±2.71 yrs). According to body mass index (BMI) chart, the subjects were divided into three groups: normal weight BMI<75th percentile, overweight BMI 75th­95th percentile, and obese>95th percentile. TyG index was calculated as (ln[fasting triglycerides(mg/dl)×fasting plasma glucose(mg/dl)/2]) and considered pathological when exceeding 7.88. HOMA-IR was calculated as (insulin×glucose)/22.5 and defined pathological whenever exceeding 97.5th percentile for age and sex. Results: In children with overweight/obesity TyG index was higher compared to normal weight subjects (p<0.001). TyG index was correlated with BMI (p<0.001); WHtR (p<0.001), total and HDL cholesterol (p<0.001); ALT (p<0.001), blood pressure (p<0.001). A correlation between TyG index and HOMAIR (p<0.001) as well as high TyG index and pathological HOMA-IR (p<0.001) were noted. The optimal cut-off for IR was considered 7.98 (sensitivity 60%; specificity 78%; AUC 0.69). Conclusions: TyG index is a useful and cost-effective index of IR among children and adolescents. The cutoff 7.98 may be used for IR risk screening in childhood obesity, but we recommend caution when used in other populations.

Delayed puberty versus hypogonadism: a challenge for the pediatrician.

Constitutional delay of growth and puberty (CDGP) is the most common cause of delayed puberty (DP), is mainly found in males, and is characterized by short stature and delayed skeletal maturation. A family history of the subject comprising the timing of puberty in the parents and physical examination may provide clues regarding the cause of DP. Delayed onset of puberty is rarely considered a disease in either sex. In fact, DP usually represents a common normal variant in pubertal timing, with favorable outcomes for final height and future reproductive capacity. In adolescents with CDGP, a linear growth delay occurs until immediately before the start of puberty, then the growth rate rapidly increases. Bone age is often delayed. CDGP is a diagnosis of exclusion; therefore, alternative causes of DP should be considered. Functional hypogonadotropic hypogonadism may be observed in patients with transient delay in hypothalamic-pituitary-gonadal axis maturation due to associated conditions including celiac disease, inflammatory bowel diseases, kidney insufficiency, and anorexia nervosa. Permanent hypogonadotropic hypogonadism (pHH) showing low serum value of testosterone or estradiol and blunted follicle-stimulating hormones (FSH) and luteinizing hormones (LH) levels may be due to abnormalities in the central nervous system. Therefore, magnetic resonance imaging is necessary to exclude morphological abnormalities and neoplasia. Moreover, pHH may be isolated, as observed in Kallmann syndrome, or associated with other hormone deficiencies, as found in panhypopituitarism. Baseline or gonadotropin-releasing hormone pituitary stimulated gonadotropin level is not sufficient to easily differentiate CDGP from pHH. Low serum testosterone in male patients and low estradiol values in female patients, associated with high serum FSH and LH levels, suggest a diagnosis of hypergonadotropic hypogonadism. A genetic analysis can reveal a chromosomal abnormality (e.g., Turner syndrome or Klinefelter syndrome). In cases where the adolescent with CDGP is experiencing psychological difficulties, treatment should be recommended.

Smoke exposure and cardio-metabolic profile in youth with type 1 diabetes.

BACKGROUND: To evaluate the relationship between smoking and metabolic parameters in patients affected by type 1 diabetes (T1D). PATIENTS AND METHODS: We enrolled 104 children and young adults (50 females and 54 males) with T1D (aged 16.4 ± 8.6 years). The subjects were divided into three groups according to their smoking habits: no smoking (NS), passive smoking (PS), active smoking (AS). The physical examination of the participants included nutritional status assessment by anthropometry and pubertal stage according to Marshall and Tanner as well as blood pressure measurement. In all patients, metabolic blood assays including fasting blood glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, and triglycerides were measured. Insulin resistance was determined by glucose disposal rate (eGDR). Physical activity was also recorded. RESULTS: Significant differences in biochemical and functional parameters among the three groups were demonstrated, in particular for systolic (p = 0.002) and diastolic pressure (p = 0.02) and eGDR (p = 0.039). No differences in daily insulin dose (p = 0.75) and glycated hemoglobin (p = 0.39) were observed. AS group had significantly higher blood pressure (p < 0.05) and lower eGDR (p ≤ 0.001) compared to NS and PS. Significant difference was also detected between PS and NS in systolic and diastolic (p = 0.02) pressure and eGDR (p = 0.01). In a multivariable model adjusted for age, gender, BMI and physical activity, smoking habits did not maintain any independent association with metabolic parameters. CONCLUSION: This is the first study in a Mediterranean population, looking at tobacco smoke and cardio-metabolic factors in youth with T1D. The relationship between smoking and unfavorable metabolic profile was demonstrated. On the basis of these findings, smoking tobacco should be considered an important modifiable risk factor for young patients with diabetes mellitus, highlighting the need for intensified smoking prevention and cessation programs.

Relation between circulating oxidized-LDL and metabolic syndrome in children with obesity: the role of hypertriglyceridemic waist phenotype.

BACKGROUND: The association between oxidative stress (OS) and metabolic syndrome (MetS) has been reported in adults. We analyzed the relation between circulating oxidized low-density lipoproteins (Ox-LDL) and MetS in pediatric ages in order to define whether plasma Ox-LDL levels are correlated to obesity and whether oxidative damage, using serum Ox-LDL levels as a proxy, are associated with MetS. METHODS: We enrolled 178 children (11.8±2.6 years). On the basis of a body mass index (BMI) threshold, the subjects were classified as: normal weight BMI <75th percentile; overweight BMI 75-97th percentile; obese BMI >97th percentile. Patients were classified as having MetS if they met three or more of the following criteria for age and sex: BMI >97th percentile, triglyceride levels >95th percentile, high-density lipoprotein (HDL) cholesterol level <5th percentile, systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) >95th percentile and impaired glucose tolerance. RESULTS: Obese children showed increased MetS prevalence (p=0.001) and higher Ox-LDL levels compared to normal- and overweight subjects (p<0.05), with a limited relation between Ox-LDL and MetS (p=0.06). Waist-to-height ratio (W/HtR) (p=0.02), triglycerides (TG) (p=0.001) and LDL-cholesterol (p<0.001) resulted independent predictors of increased plasma Ox-LDL levels. CONCLUSIONS: Oxidative damage was correlated with a hypertriglyceridemic waist phenotype and can be a precocious marker of MetS and cardiometabolic risk in obese children.