Plasma fatty acid esters of hydroxy fatty acids and surrogate fatty acid esters of hydroxy fatty acids hydrolysis activity in children with or without obesity and in adults with or without coronary artery disease.

AIM: Fatty acid esters of hydroxy fatty acids (FAHFA) are a class of bioactive lipids with anti-inflammatory, antidiabetic and cardioprotective properties. FAHFA hydrolysis into its fatty acid (FA) and hydroxy fatty acid (HFA) constituents can affect the bioavailability of FAHFA and its subsequent biological effects. We aimed to investigate FAHFA levels and FAHFA hydrolysis activity in children with or without obesity, and in adults with or without coronary artery disease (CAD). MATERIALS AND METHODS: Our study cohort included 20 children without obesity, 40 children with obesity, 10 adults without CAD and 28 adults with CAD. We quantitated plasma levels of four families of FAHFA [palmitic acid hydroxy stearic acid (PAHSA), palmitoleic acid hydroxy stearic acid (POHSA), oleic acid hydroxy stearic acid (OAHSA), stearic acid hydroxy stearic acid] and their corresponding FA and HFA constituents using liquid chromatography-tandem mass spectrometry analysis. Surrogate FAHFA hydrolysis activity was estimated as the FA/FAHFA or HFA/FAHFA ratio. RESULTS: Children with obesity had lower plasma PAHSA (p = .001), OAHSA (p = .006) and total FAHFA (p = .011) levels, and higher surrogate FAHFA hydrolysis activity represented by PA/PAHSA (p = .040) and HSA/OAHSA (p = .025) compared with children without obesity. Adults with CAD and a history of myocardial infarction (MI) had lower POHSA levels (p = .026) and higher PA/PAHSA (p = .041), POA/POHSA (p = .003) and HSA/POHSA (p = .038) compared with those without MI. CONCLUSION: Altered FAHFA metabolism is associated with obesity and MI, and inhibition of FAHFA hydrolysis should be studied further as a possible therapeutic strategy in obesity and MI.

Novel Melanocortin-3 and -4 Receptor Functional Variants in Asian Children With Severe Obesity.

CONTEXT: Genetic variants in melanocortin 3 receptor (MC3R) and melanocortin 4 receptor (MC4R) genes are strongly associated with childhood obesity. OBJECTIVE: This study aims to identify and functionally characterize MC3R and MC4R variants in an Asian cohort of children with severe early-onset obesity. METHODS: Whole-exome sequencing was performed to screen for MC3R and MC4R coding variants in 488 Asian children with severe early-onset obesity (body mass index for age ≥97th percentile). Functionality of the identified variants were determined via measurement of intracellular cyclic adenosine monophosphate (cAMP) concentrations and luciferase activity. RESULTS: Four MC3R and 2 MC4R heterozygous nonsynonymous rare variants were detected. There were 3 novel variants: MC3R c.151G > C (p.Val51Leu), MC4R c.127C > A (p.Gln43Lys), and MC4R c.272T > G (p.Met91Arg), and 3 previously reported variants: MC3R c.127G > A (p.Glu43Lys), MC3R c.97G > A (p.Ala33Thr), and MC3R c.437T > A (p.Ile146Asn). Both MC3R c.127G > A (p.Glu43Lys) and MC4R c.272T > G (p.Met91Arg) variants demonstrated defective downstream cAMP signaling activity. The MC4R c.127C > A (p.Gln43Lys) variant showed reduced cAMP signaling activity at low substrate concentration but the signaling activity was restored at high substrate concentration. The MC3R c.151G > C (p.Val51Leu) variant did not show a significant reduction in cAMP signaling activity compared to wild-type (WT) MC3R. Coexpression studies of the WT and variant MC3R/MC4R showed that the heterozygous variants did not exhibit dominant negative effect. CONCLUSION: Our functional assays demonstrated that MC3R c.127G > A (p.Glu43Lys) and MC4R c.272T > G (p.Met91Arg) variants might predispose individuals to early-onset obesity, and further studies are needed to establish the causative effect of these variants in the pathogenesis of obesity.

Quality of life and psychosocial outcomes among children with metabolically healthy and unhealthy obesity.

BACKGROUND: Obesity and obesity-related morbidities are associated with poor psychosocial adjustment and health-related quality of life (HRQoL). This study aims to examine HRQoL and psychosocial outcomes in children with metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO), and the effects of familial health on these outcomes. METHODS: Four hundred and six children with BMI for age ≥ 97th percentile were classified as having MHO and MUO based on the absence or presence of metabolic abnormalities. HRQoL and psychosocial outcomes were assessed using validated questionnaires such as PedsQL and DASS-21. RESULTS: There were no significant differences in HRQoL and psychosocial outcomes between children with MHO and children with MUO. Children with MUO and prior knowledge of existing metabolic conditions reported significantly lower total HRQoL (71.18 ± 17.42 vs. 75.34 ± 15.33), and higher depression (12.16 ± 11.80 vs. 8.95 ± 8.52) and stress (12.11 ± 8.21 vs. 10.04 ± 7.92) compared to children with MHO. Children with MUO who had fathers with metabolically unhealthy phenotype reported significantly lower total HRQoL (72.41 ± 15.67 vs. 76.82 ± 14.91) compared to children with MUO who had fathers with metabolically healthy phenotype. CONCLUSION: Prior knowledge of existing metabolic abnormalities was associated with poorer HRQoL and mental health in children with obesity. Paternal metabolic health status influenced HRQoL in children with MUO. IMPACT: First study that compared health-related quality of life (HRQoL) and psychosocial outcomes between children with metabolically healthy obesity (MHO) and children with metabolically unhealthy obesity (MUO). No significant differences in HRQoL and psychosocial outcomes between children with metabolically healthy obesity (MHO) and children with metabolically unhealthy obesity (MUO). Children with MUO who had prior knowledge of existing metabolic conditions reported lower HRQoL, higher depression and stress compared to children with MHO. Paternal metabolic health status was found to influence HRQoL in children with MUO. Mental health support intervention with paternal involvement should be provided for children with MUO.

Dietary Intakes and Eating Behavior between Metabolically Healthy and Unhealthy Obesity Phenotypes in Asian Children and Adolescents.

Diet plays a critical role in the development of obesity and obesity-related morbidities. Our study aimed to evaluate the dietary food groups, nutrient intakes and eating behaviors of metabolically healthy and unhealthy obesity phenotypes in an Asian cohort of children and adolescents. Participants (n = 52) were asked to record their diet using a 3-day food diary and intakes were analyzed using a nutrient software. Eating behavior was assessed using a validated questionnaire. Metabolically healthy obesity (MHO) or metabolically unhealthy obesity (MUO) were defined based on criteria of metabolic syndrome. Children/adolescents with MUO consumed fewer whole grains (median: 0.00 (interquartile range: 0.00-0.00 g) vs. 18.5 g (0.00-69.8 g)) and less polyunsaturated fat (6.26% kcal (5.17-7.45% kcal) vs. 6.92% kcal (5.85-9.02% kcal)), and had lower cognitive dietary restraint (15.0 (13.0-17.0) vs. 16.0 (14.0-19.0)) compared to children/adolescents with MHO. Deep fried food, fast food and processed convenience food were positively associated with both systolic (ß: 2.84, 95%CI: 0.95-6.62) and diastolic blood pressure (ß: 4.83, 95%CI: 0.61-9.04). Higher polyunsaturated fat intake (OR: 0.529, 95%CI: 0.284-0.986) and cognitive dietary restraint (OR: 0.681, 95%CI: 0.472-0.984) were associated with a lower risk of the MUO phenotype. A healthier diet composition and positive eating behavior may contribute to favorable metabolic outcomes in children and adolescents with obesity.

Prevalence and predictors of metabolically healthy obesity in severely obese Asian children.

BACKGROUND: Obese individuals who have little or no metabolic syndrome components are proposed to be "metabolically healthy obese (MHO)". This study aim to evaluate the prevalence of MHO and examine the predictors associated with MHO in a multi-ethnic Asian cohort of severely obese children. METHODS: This study included a cross-sectional cohort of 406 Chinese, Malay and Indian children aged 5-20 years old with BMI for age ≥ 97th percentile. Metabolic syndrome (MS) and metabolic health (MH) definitions based on the presence or absence of metabolic abnormalities (High triglycerides, low HDL cholesterol, elevated blood pressure and high glucose) were used to define MHO in the cohort. RESULTS: The prevalence of MHO is 63.5% by MS definition and 22.4% by MH definition. Maternal healthy metabolic status (OR: 2.47), age (OR: 0.83, 0.80), paternal obesity (OR: 0.48, 0.53), Malay (OR: 1.97) and Indian ethnicity (OR: 6.38, 3.21) (compared to Chinese ethnicity) are independent predictors for MHO phenotype based on different MHO definitions. CONCLUSIONS: Adiposity measures are not associated with MHO phenotype, but instead younger age, maternal healthy metabolic status, absence of paternal obesity, Malay and Indian ethnicity are independent predictors for MHO phenotype in a multi-ethnic Asian cohort of severely obese children. IMPACT: The prevalence of metabolically healthy obese (MHO) in our multi-ethnic Asian cohort of severely obese children is 63.5% and 22.4%, respectively, based on different MHO definitions. Adiposity measures are not associated with the MHO phenotype. There are other factors that contribute to the metabolic phenotype in obese individuals. Younger age, maternal healthy metabolic status, absence of paternal obesity, Malay and Indian ethnicity are independent predictors for MHO phenotype. Parental influence is important in predicting metabolic health in obese individuals.

Association of leukocyte telomere length with obesity-related traits in Asian children with early-onset obesity.

BACKGROUND: Leukocyte telomere length (LTL) is associated with obesity and obesity-related traits, and there are ethnic-specific determinants of LTL. OBJECTIVE: To evaluate LTL associations with obesity and metabolic parameters in Asian children with early-onset obesity. METHODS: Genomic DNA was extracted from peripheral blood leukocytes of a cohort of children with (N = 371) and without obesity (N = 23), and LTL was measured using quantitative PCR (qPCR). Blood plasma was used for metabolic phenotyping. Statistical analysis was performed using SPSS and STATA. RESULTS: Children with obesity had shorter LTL (coefficient = -0.683, PAdj = 1.24 × 10-3 ) as compared to children who were lean. LTL was found to be associated with waist circumference (coefficient = -0.326, PAdj = 0.044) and skin-fold measures (coefficient between 0.267 and 0.301, PAdj between 4.27 × 10-4 and 7.06 × 10-7 ) in children with obesity. However, no significant associations were observed between LTL and metabolic parameters, and between LTL and inflammatory cytokines. LTL also did not significantly mediate the risk of non-alcoholic fatty liver disease (NAFLD) in children with obesity. CONCLUSIONS: We showed for the first time that Asian children with severe obesity had shorter LTL, and the shortening of LTL was associated with other adiposity measures including waist circumference and skin-fold measurements.

Genetic testing of GCK-MODY identifies a novel pathogenic variant in a Chinese boy with early onset hyperglycemia.

Glucokinase-maturity-onset diabetes of the young (GCK-MODY or MODY 2), caused by a heterozygous inactivating variant in the Glucokinase (GCK) gene, is a common form of MODY. Here, we present a case of GCK-MODY in a young Chinese boy, his sister and his father with a novel pathogenic variant in exon 8 of the GCK gene, NM_000162.5:c.1015del, p.(Glu339Argfs*14), which is predicted to cause a significant change in protein structure and function.

Self and parent-proxy rated health-related quality of life (HRQoL) in youth with obesity: are parents good surrogates?

PURPOSE: Consideration of health-related quality of life (HRQoL) and wellbeing outcomes is important to guide healthcare services for youth with obesity, yet youth perspectives may differ from their parents. This study compared youth and parental HRQoL reports and evaluated levels of concordance across HRQoL domains and as a function of youth age, youth gender and parent informant (mother and father). METHODS: 376 youths with obesity, recruited from community (N = 223) and hospital settings (N = 153), and their parents (N = 190 mothers; N = 91 fathers), completed the PedsQL. Parental and youth agreement across subgroup dyads (mother; father; child gender; child age) were evaluated using Wilcoxon signed-rank test, intra-correlations coefficients (ICCs) and Bland-Altman plots. RESULTS: Compared to norms, HRQoL levels (youth self-report and parental proxy reports) were lower in all domains. Both mother and fathers' HRQoL reports were significantly lower than youths, most notably in physical HRQoL. Youth-parent concordance ranged from poor to moderate (ICC = 0.230-0.618), with lowest agreement for Physical HRQOL. Mothers were better proxies with ICCs being significant in all domains. Youth-father ICCs were significant only for Social (ICC = 0.428) and School (ICC = 0.303) domains. Girl-mother agreement was significant across all domains, while girl-father agreement was significant only in the Social domain (ICC = 0.653). Both mothers and fathers were poor raters for boys, and younger youths (aged ≤ 12), with non-significant ICCs in most HRQoL domains. CONCLUSIONS: Parents are poor surrogates for youth HRQoL. Clinicians should be cognizant that parents are not necessarily accurate proxies for youths, and exercise caution when interpreting parent-proxy scores.

Acute hemichorea in a young type 1 diabetic.

Purpose/Aim: Acute movement disorder is an uncommon presenting symptom in patients with diabetes mellitus. We report a 20-year-old lady with poorly controlled type 1 diabetes, who presented with acute hemichorea and was found to have two rare diabetes-related central nervous complications of diabetic striatopathy and severe moyamoya disease (MMD).Materials and methods: She was treated with aggressive glycemic control; clonazepam and tetrabenazine as well as aspirin stroke prophylaxis for her MMD with resolution of her chorea 3 months later. She subsequently underwent cerebral revascularization surgery for her MMD.Results: This case highlights the possible differentials of acute chorea in diabetic patients and explores the pathophysiological mechanisms that may underlie both conditions in patients with type 1 diabetes.Conclusion: We recommend performing both magnetic resonance imaging (MRI) and magnetic resonance angiogram (MRA) brain for comprehensive evaluation of diabetic patients with new onset chorea. Prompt and accurate diagnosis is crucial as it guides prognostication and treatment strategies.

A diagnostic curiosity of isolated androstenedione elevation due to autoantibodies against horseradish peroxidase label of the immunoassay.

Two sisters with hirsutism presented with mild hirsutism and isolated, grossly elevated (>34.9nmol/L) serum concentrations of androstenedione measured by competitive, homogeneous immunoassay. The clinically discordant laboratory results prompted us to look for assay interference. In this immunoassay, horseradish peroxidase (HRP)-conjugated androstenedione competes with endogenous androstenedione for binding with the solid-phase polyclonal rabbit IgG antibodies. After a wash step, the amount of signal generated by the bound HRP conjugate is inversely proportional to the androstenedione concentration. Alternative analysis by tandem mass spectrometry (a good first line option for troubleshooting) and repeating the competitive immunoassay after polyethylene glycol treatment returned androstenedione concentrations within reference limits. These findings suggested that the original result was spuriously elevated due to assay interference. Additionally, the patient samples were pre-incubated with heterophile blocking reagents, normal rabbit IgG antibodies and HRP-conjugated normal goat IgG antibodies, followed by repeat measurement using the immunoassay. Only samples pre-incubated with HRP-conjugate returned significantly lower androstenedione (9.5 and 12.5nmol/L, respectively), implying neutralisation of the interfering antibodies. Androstenedione remained grossly elevated in the other experiments. This deductive exercise showed that the interference is due to autoantibodies against the HRP label used in the immunoassay. Another immunoassay using HRP label (5α-dihydrotestosterone) also produced gross elevation that was normal by tandem mass spectrometry analysis. Assay interferences, though not uncommon, are frequently overlooked. Laboratory results discordant with clinical features should prompt consideration of assay interference to avoid unnecessary investigations and treatment. This is the first report of autoantibodies against the HRP label used in immunoassay.

Genetic Testing Confirmed the Early Diagnosis of X-Linked Hypophosphatemic Rickets in a 7-Month-Old Infant.

Loss-of-function mutations in the phosphate regulating gene with homologies to endopeptidases on the X-chromosome (PHEX) have been causally associated with X-linked hypophosphatemic rickets (XLHR). The early diagnosis of XLHR in infants is challenging when it is based solely on clinical features and biochemical findings. We report a 7-month-old boy with a family history of hypophosphatemic rickets., who demonstrated early clinical evidence of rickets, although serial biochemical findings could not definitively confirm rickets. A sequencing assay targeting the PHEX gene was first performed on the mother's DNA to screen for mutations in the 5'UTR, 22 coding exons, and the exon-intron junctions. Targeted mutation analysis and mRNA studies were subsequently performed on the boys' DNA to investigate the pathogenicity of the identified mutation. Genetic screening of the PHEX gene revealed a novel mutation, c.1080-2A>C, at the splice acceptor site in intron 9. The detection of an aberrant mRNA transcript with skipped (loss of) exon 10 establishes its pathogenicity and confirms the diagnosis of XLHR in this infant. Genetic testing of the PHEX gene resulted in early diagnosis of XLHR, thus enabling initiation of therapy and prevention of progressive rachitic changes in the infant.