Cross-sectional study investigating the association between inflammatory biomarkers and neuropathy in adolescents with type 1 diabetes.

OBJECTIVES: The aims of this study were to investigate circulating levels of inflammatory markers in adolescents with type 1 diabetes with and without different types of neuropathies and evaluate the association between inflammatory biomarkers, nerve function and clinical parameters. DESIGN: Cross-sectional study. SETTING: Hospitals and Steno Diabetes Center in Denmark. PARTICIPANTS: Adolescents with more than 5 years of diabetes duration were investigated for large fibre, small fibre and autonomic neuropathy as a part of the T1DANES study. Blood samples from the participants were analysed for inflammatory biomarkers by Meso Scale Discovery multiplexing technology. PRIMARY AND SECONDARY OUTCOME MEASURES: Inflammatory biomarkers and results of diagnostic nerve tests. RESULTS: Fifty-six adolescents with type 1 diabetes and 23 healthy controls were included. The adolescents with diabetes had significantly higher interferon-gamma, tumour necrosis factor-alpha (TNF-a), interleukin (IL)-10 and soluble urokinase plasminogen activator receptor (suPAR) compared with healthy controls (p values<0.05). TNF-a was higher in the adolescents with large fibre neuropathy (LFN) (p=0.03) compared with those without LFN in the group with diabetes. A negative correlation was seen between TNF-a and conduction velocity in nervus tibialis (p=0.04), and higher TNF-a and IL-6 were associated with higher gastric motility index (TNF-a, p value=0.03; IL-6, p value=0.02). There were no significant associations between inflammatory markers and expressed symptoms, haemoglobin A1c, diabetes duration or body mass index standard derivation score (p values>0.05). The receiver operating characteristic (ROC) curves for the inflammatory markers suggested them as poor screening methods for all types of neuropathies with an area under the curve between 0.47 and 0.67. CONCLUSION: Our results confirm increased low-grade inflammation in adolescents with type 1 diabetes. TNF-a was higher in adolescents with LFN and correlated negatively with nervus tibialis conduction velocity. The other inflammatory biomarkers fail to support differences in those with and without different types of diabetic neuropathies. However, TNF-a and IL-6 were positively correlated to gastric motility index.

Neuropathy in adolescents with type 1 diabetes: Confirmatory diagnostic tests, bedside tests, and risk factors.

AIMS: To estimate the prevalence of large fiber (LFN), small fiber (SFN), and autonomic neuropathy in adolescents with type 1 diabetes using confirmatory tests known from adults and to identify risk factors and bedside methods for neuropathy. METHODS: Sixty adolescents with type 1 diabetes (diabetes duration > five years) and 23 control subjects underwent neurological examination and confirmatory diagnostic tests for neuropathy, including nerve conduction studies, skin biopsies determining intraepidermal nerve fiber density, quantitative sudomotor axon reflex test (QSART), cardiovascular reflex tests (CARTs), and tilt table test. Possible risk factors were analyzed. Bedside tests (biothesiometry, DPNCheck®, Sudoscan, and Vagus®device) were compared with the confirmatory tests using ROC analysis. RESULTS: The prevalence of neuropathies in the adolescents with diabetes (mean HbA1c 7.6% (60 mmol/mol)) was as follows: 14% confirmed/26% subclinical LFN, 2% confirmed/25% subclinical SFN, 20% abnormal QSART, 8% abnormal CARTs, and 14% orthostatic hypotension. Higher age, higher insulin dose, previous smoking, and higher triglycerides level were found to increase the relative risk for neuropathy. The bedside tests showed poor to acceptable concordance with the confirmatory tests (all, AUC ≤ 0.75). CONCLUSIONS: The diagnostic tests confirmed the presence of neuropathy in adolescents with diabetes and underscore the importance of prevention and screening.

Treatment of type 2 diabetes in children: what are the specific considerations?

Introduction: The number of individuals under 18 years of age with type 2 diabetes is increasing at an alarming rate worldwide. These patients are often characterized by obesity and they often experience a more rapid disease progression than adults with type 2 diabetes. Thus, focus on prevention and management of complications and comorbidities is imperative. With emphasis on weight loss and optimal glycemic control, treatment includes lifestyle changes and pharmacotherapy, which in this patient group is limited to metformin, liraglutide and insulin. In selected cases, bariatric surgery is indicated.Areas covered: This perspective article provides an overview of the literature covering pathophysiology, diagnosis, characteristics and treatment of pediatric type 2 diabetes, and outlines the gaps in our knowledge where further research is needed. The paper draws on both mechanistic studies, large scale intervention trials, epidemiological studies and international consensus statements.Expert opinion: Type 2 diabetes in pediatric patients is an increasing health care problem, and the current treatment strategies do not successfully meet the many challenges and obstacles in this patient group. Treatments must be early, intensive, multifaceted and durable. Also, prevention of obesity and type 2 diabetes in at-risk children should be addressed and prioritized on all levels.

Screening for retinopathy in children with type 1 diabetes in Denmark.

BACKGROUND/OBJECTIVE: Children with type 1 diabetes (T1D) are screened regularly for retinopathy with fundus photography to prevent visual impairment. According to Danish national guidelines, screening should take place at age 12, 15, and 18 years after minimum 3 years of diabetes. As glycemic control has improved, prevalence of retinopathy is expected to be decreased. The aim of this study is to investigate the prevalence, degree, and progression of retinopathy in children with T1D and to explore if screening at 12 years is currently indicated in Denmark. METHODS: Data on all Danish children with onset of T1D from 2003 to 2013 (n = 2943) were collected from the "DanDiabKids" registry. For children with registered screenings (n = 2382), prevalence of retinopathy at 12, 15, and 18 years was determined. In children with retinopathy, subsequent screenings were studied to reveal if retinopathy was persistent or temporary. RESULTS: Prevalence of retinopathy at 12, 15, and 18 years was 0.9%, 2.3%, and 3.1%, respectively. Minimal background retinopathy was seen in over 90% and 100% at 12 years. In available re-screenings, retinopathy resolved spontaneously in 87.5% of all cases and 100% of cases at 12 years. CONCLUSIONS: The prevalence of retinopathy in Danish children with T1D was low. At 12 years, prevalence was 0.9% and exclusively minimal background retinopathy with 100% remission in re-screenings. Thus, screening at this age does not seem to have significant clinical relevance. We propose more individualized screening selection before the age of 15.

The follicle-stimulating hormone (FSH) and luteinizing hormone (LH) response to a gonadotropin-releasing hormone analogue test in healthy prepubertal girls aged 10 months to 6 years.

OBJECTIVE: Premature thelarche and precocious puberty are frequently diagnosed in girls even below 6 years of age and may be difficult to differentiate in the early stages. A GnRH test is often included in the diagnostic work-up, although interpretation of the GnRH test in girls below 6 years of age is challenging, as no reference interval exists for this age group. The objective is to determine the normal FSH and LH response to a GnRH test in healthy prepubertal girls below 6 years of age. DESIGN AND METHODS: A standardized GnRH test, baseline reproductive hormones, clinical evaluation and bone age were determined in all participants. Forty-eight healthy normal-weight girls aged 3.5 ± 0.2 years (range: 0.8-5.9 years) were included. Serum concentrations of LH and FSH were measured before and 30 min after the gonadorelin injection. RESULTS: The 30-min LH responses (mean ± 2 s.d.) were 5.2 ± 4.0 and 2.9 ± 2.5 IU/L and the FSH responses were 23.3 ± 16.2 and 14.5 ± 10.3 IU/L in girls aged 0.8-3.0 years and 3.0-5.9 years respectively. This corresponds to upper cut-off limits for LH of 9.2 IU/L (<3 years) and 5.3 IU/L (3-6 years). The stimulated LH/FSH ratio was 0.23 ± 0.19 (range 0.06-0.43) and did not correlate with age. CONCLUSIONS: We found that LH increases up to 9.2 IU/L during GnRH test in healthy normal-weight girls below 3 years of age and that the stimulated LH/FSH ratio did not exceed 0.43. Our findings have important implications for appropriate diagnosis of central precocious puberty in girls below 6 years of age.

Cushing's syndrome in children and adolescents: a Danish nationwide population-based cohort study.

OBJECTIVE: Cushing's syndrome (CS) affects all age groups, but epidemiologic data in young patients are very limited. We therefore examined the incidence, prevalence and hospital morbidity of CS in children and adolescents. DESIGN: In a nationwide cohort study, we included all Danish citizens aged 0-20 years from 1977 to 2012. Data were obtained from the Danish National Patient Registry using the International Classification of Diseases (ICD) codes and the Danish Civil Registration System. The diagnosis and treatment were validated by means of individual patient charts. Incidence rate of CS patients aged 0-20 years at diagnosis were computed (standardized to the age and sex distribution of the Danish population). The patients were followed for a maximum of 36 years. Standardized incidence ratios (SIRs) of different hospital-recorded outcomes based on the ICD codes in patients with CS compared to the general population were assessed. RESULTS: We identified a total of 40 pediatric patients with CS, yielding an annual incidence of 0.89 cases/106 population (95% confidence interval (CI) = 0.63-1.16). The median age at the time of diagnosis was 13.8 years (interquartile range: 10.5-18.2 years), 58% were female and 70% had adrenocorticotropic hormone-producing pituitary adenomas. During follow-up, CS patients (excluding three malignant cases) were at increased risk of being diagnosed with infections (SIR: 3.24, 95% CI: 1.05-7.54) and infertility (SIR: 4.56, 95% CI: 1.48-10.63). The three patients with an adrenocortical carcinoma died shortly after diagnosis, but mortality was not increased in the remaining patients. CONCLUSIONS: CS is rare in the pediatric population. The risk of morbidity related to infections and infertility is elevated and merits further attention.

[Genetic screening for mutations enables early diagnosis of pituitary adenomas]. / Genetisk screening for mutation muliggør tidlig diagnostik af hypofyseadenomer.

Mutations in the aryl hydrocarbon receptor interaction protein gene (AIP) occur in familial pituitary adenomas as an autosomal dominant inheritance with a 15-30% penetrance. The AIP mutation-associated pituitary adenomas are generally large, the onset of disease is early and treatment failure frequent. Genetic screening is also offered in Denmark and enables the detection of mutation carriers, and thus early diagnosis and treatment. Mutations have been recorded among Danish patients and their families.

Gene expression of the GH receptor in subcutaneous and intraabdominal fat in healthy females: relationship to GH-binding protein.

OBJECTIVE: Circulating GH-binding protein (GHBP) is produced by proteolytical cleavage of the extracellular part of the GH receptor (GHR) and is positively correlated to the amount of body fat. To test the hypothesis that adipose tissue may contribute to the production of circulating GHBP, we compared gene expression of two GHR isoforms in adipose tissue with serum GHBP concentrations in healthy females. DESIGN: Twenty-two healthy females undergoing surgery for benign gynecological conditions were included in the study. METHODS: During surgery, s.c. and intraabdominal fat biopsy samples were taken. Gene expression of the full-length GHR and a truncated GHR (GHRtr) was assessed by RT-PCR relative to the expression of beta-actin. RESULTS: The full-length GHR was expressed to a much higher level than GHRtr in both tissues. The levels of both GHR and GHRtr mRNA were similar in intraabdominal and s.c. adipose tissues. Surprisingly, concentrations of circulating GHBP were negatively correlated to the levels of mRNA transcripts of both the full-length GHR and GHRtr in intraabdominal fat. Whole body resistance (as a measure of lean body mass) was positively correlated to mRNA levels for both GHRs in intraabdominal fat. CONCLUSIONS: (i) The full-length GHR is expressed to a much higher level than GHRtr in s.c. as well as visceral abdominal fat; (ii) the observation of a significant correlation between GHR expression and GHBP levels further emphasizes the link between adipose tissue and GHBP; (iii) it remains, however, to be demonstrated whether circulating GHBP is produced to a significant degree by adipose tissue.

Estrogen controls lipolysis by up-regulating alpha2A-adrenergic receptors directly in human adipose tissue through the estrogen receptor alpha. Implications for the female fat distribution.

Estrogen seems to promote and maintain the typical female type of fat distribution that is characterized by accumulation of adipose tissue, especially in the sc fat depot, with only modest accumulation of adipose tissue intraabdominally. However, it is completely unknown how estrogen controls the fat accumulation. We studied the effects of estradiol in vivo and in vitro on human adipose tissue metabolism and found that estradiol directly increases the number of antilipolytic alpha2A-adrenergic receptors in sc adipocytes. The increased number of alpha2A-adrenergic receptors caused an attenuated lipolytic response of epinephrine in sc adipocytes; in contrast, no effect of estrogen on alpha2A-adrenergic receptor mRNA expression was observed in adipocytes from the intraabdominal fat depot. These findings show that estrogen lowers the lipolytic response in sc fat depot by increasing the number of antilipolytic alpha2A-adrenergic receptors, whereas estrogen seems not to affect lipolysis in adipocytes from the intraabdominal fat depot. Using estrogen receptor subtype-specific ligands, we found that this effect of estrogen was caused through the estrogen receptor subtype alpha. These findings demonstrate that estrogen attenuates the lipolytic response through up-regulation of the number of antilipolytic alpha2A-adrenergic receptors only in sc and not in visceral fat depots. Thus, our findings offer an explanation how estrogen maintains the typical female sc fat distribution because estrogen seems to inhibit lipolysis only in sc depots and thereby shifts the assimilation of fat from intraabdominal depots to sc depots.

Anti-glucocorticoid effects of progesterone in vivo on rat adipose tissue metabolism.

Steroid hormones seem to be important for adipose tissue metabolism and accumulation. As progesterone has been suggested to modulate the glucocorticoid effects, the interactions between glucocortioid and progesterone on adipose tissue metabolism were investigated.Forty-eight male Wistar rats were adrenectomized and divided into four groups; controls (treated with vehicle only), dexamethasone treated (10 micro g per rat), progesterone treated (5mg per rat) and the last group received both dexamethasone and progesterone. The dexamethasone-treated group had a significant loss of body weight and smaller intra-abdominal fat depots compared to the control group in addition, dexamethasone increased LPL-activity and increased catecholamine stimulated lipolysis. When progesterone was given concomitantly the dexamethasone effects on adipose tissue mass, LPL-activity and lipolysis were blocked. When given alone progesterone had no influence on body weight, amount of adipose tissue, lipolysis or LPL-activity. These data indicate that progesterone acts as an anti-glucocorticoid in adipose tissue in vivo, thus attenuating the glucocorticoid effect on adipose tissue metabolism.

Opposite regulation of interleukin-8 and tumor necrosis factor-alpha by weight loss.

OBJECTIVE: To obtain more information on the possible influence of body mass index (BMI) and weight loss on interleukin-8 (IL-8) in plasma and in the adipose tissue. Tumor necrosis factor-alpha (TNF-alpha) was used for comparison and determined in parallel with IL-8. RESEARCH METHODS AND PROCEDURES: The study was divided into three parts: 1) a cross-sectional study that included 89 subjects; 2) a 20-week intervention study in which 34 healthy obese subjects received a dietary intervention for 8 weeks followed by an additional 12 weeks on a weight-stabilization diet; 3) from this latter study, a subgroup of 8 obese subjects was investigated with a subcutaneous adipose-tissue biopsy. RESULTS: In the cross-sectional study, plasma levels of TNF-alpha (p < 0.01), but not IL-8, was correlated with BMI. However, in a subgroup (BMI, 20 to 30 kg/m(2)), IL-8 was correlated with BMI (p < 0.01). In the intervention study, weight loss and weight maintenance led to an increase in IL-8 by 30% (p < 0.05) and a decrease in TNF-alpha by 40% (p < 0.001), which were paralleled in the adipose tissue, demonstrating a 2- to 3-fold increase (p < 0.01) and a 40% to 80% decrease (p < 0.01) in IL-8 and TNF-alpha, respectively. DISCUSSION: Weight loss in obese subjects was associated with opposite changes in the secretion and transcription of IL-8 and TNF-alpha in the adipose tissue, as well as in plasma. This could indicate that plasma IL-8 under some conditions may be related to changes in adipose tissue IL-8 production.

Effects of pro-inflammatory cytokines and chemokines on leptin production in human adipose tissue in vitro.

Leptin is synthesized in adipocytes and acts primarily through central pathways suppressing appetite and increasing the metabolic rate in rodents as well as in humans. Recently leptin has also been suggested to have peripheral effects and be involved in insulin action. Since cytokines and chemokines may have effects on appetite regulation as well as on some of the obesity-related complications e.g. insulin resistance and cardiovascular disease, we investigated the effects of various cytokines and chemokines on leptin production in human adipose tissue fragments in vitro. Abdominal subcutaneous adipose tissue from healthy normal to overweight females was incubated for up to 48 h with the cytokines: tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1beta (IL-1beta) and the chemokine: interleukin-8 (IL-8). IL-1beta (50 ng/ml) and TNF-alpha (10 ng/ml) decreased leptin production by 30-50% (P<0.05) and gene expression by 80-90% (P<0.05). In contrast, IL-6 and IL-8 had no effect on either leptin production or leptin gene expression. Interestingly, IL-1beta elicited a biphasic effect on leptin release with an incremental phase observed within 4 h with no concomitant change in leptin gene expression, followed by a long-lasting inhibition of leptin release and leptin gene expression. This could suggest that IL-1beta through a post-translational pathway induced an acute increase in leptin-secretion, perhaps through the release of leptin from a pre-formed pool within the adipose tissue. The long-term decrease in both leptin secretion and transcription could indicate that pro-inflammatory cytokines such as IL-1beta and TNF-alpha might influence the circulating leptin levels and thereby influence the adipose tissue to brain signalling, which could be of importance in relation to the obesity-associated diseases such as insulin resistance and cardiovascular disease.