Excessive intake of fructose increases lipogenesis in the liver, leading to hepatic lipid accumulation and development of fatty liver disease. Metabolic alterations in the liver due to fructose intake have been reported in many studies, but the effect of fructose administration on hepatic gluconeogenesis is not fully understood. The aim of this study was to evaluate the acute effects of fructose administration on fasting-induced hepatic gluconeogenesis. C57BL/6J mice were administered fructose solution after 14 h of fasting and plasma insulin, glucose, free fatty acids, and ketone bodies were analysed. We also measured phosphorylated AKT and forkhead box O (FoxO) 1 protein levels and gene expression related to gluconeogenesis in the liver. Furthermore, we measured glucose production from pyruvate after fructose administration. Glucose-administered mice were used as controls. Fructose administration enhanced phosphorylation of AKT in the liver, without increase of blood insulin levels. Blood free fatty acids and ketone bodies concentrations were as high as those in the fasting group after fructose administration, suggesting that insulin-induced inhibition of lipolysis did not occur in mice administered with fructose. Fructose also enhanced phosphorylation of FoxO1 and suppressed gluconeogenic gene expression, glucose-6-phosphatase activity, and glucose production from pyruvate. The present study suggests that acute fructose administration suppresses fasting-induced hepatic gluconeogenesis in an insulin-independent manner.

A 72-year-old woman presented with repeated hypoglycemic and hyperglycemic episodes because of an insulin allergy. On admission, she was diagnosed with type B insulin resistance syndrome. She was also found to have anti-insulin antibodies. After steroid therapy, glycemic control improved dramatically accompanied by the disappearance of the insulin allergy. We then introduced liraglutide, which successfully stabilized her glycemic episodes without allergic reactions. Liraglutide might be useful to treat patients with severe insulin allergy. (J Diabetes Invest,

BackgroundDiabetes mellitus (DM) and primary aldosteronism (PA) have been reported to induce drug-resistant hypertension and atherosclerosis. It is likely that blood pressure (BP) control becomes far more difficult in PA patients with DM. However, precise clinical characteristics of PA with type 2 DM especially in the aspect of BP control are not clear.MethodsThe study included 18 patients who were diagnosed as PA with DM and 52 PA patients without DM who matched age and sex and chosen as a control group. We have compared differences in BP control, use of antihypertensive agents and clinical characteristics between PA patients with and without DM.ResultsThere was no difference with regard to the duration of hypertension and BP control between either group. Interestingly, the PA with DM group was found to require more antihypertensive agents than the PA without DM group (number of antihypertensive agents used, 2.0 ± 1.5 vs. 1.3 ± 1.1; P < 0.05, respectively). In the 28 patients who underwent measurement of central BP (CBP) values, plasma aldosterone concentration (PAC) was high in the PA with DM group. Furthermore, a positive correlation was shown between PAC and CBP (r = 0.58; P < 0.01); the higher the PAC, the higher the CBP of patient.ConclusionsThese results might suggest that hypertension becomes more difficult to control in PA patients with DM in the future.

Dyshormonogenic congenital hypothyroidism (CH) generally results from biallelic defects in thyroid hormone synthesis genes. Whole exome sequencing allows easier identification of multiple gene defects. Two Sudanese families with CH resulting from oligogenic defects identified by whole exome sequencing are presented. In family 1, the proposita with CH and goiter was heterozygous for three TPO, one TG, and one DUOX2 mutations, including three novel variants inherited from both parents. In family 2, two brothers with psychomotor delay and goiter were homozygous for digenic mutations in the DUOX2 and DUOX1 genes, while their asymptomatic parents were heterozygous. Accumulation of pathogenic mutations may contribute to CH.

Context Congenital hypothyroidism (CH) is due to dyshormonogenesis in 10% to 15% of subjects worldwide but accounts for 60% of CH cases in the Sudan. Objective To investigate the molecular basis of CH in Sudanese families. Design Clinical phenotype reporting and serum thyroid hormone measurements. Deoxyribonucelic acid extraction for whole-exome sequencing and Sanger sequencing. Setting University research center. Patients Twenty-six Sudanese families with CH. Intervention Clinical evaluation, thyroid function tests, genetic sequencing, and analysis. Our samples and information regarding samples from the literature were used to compare TG (thyroglobulin) and TPO (thyroid peroxidase) mutation rates in the Sudanese population with all populations. Results Mutations were found in dual-oxidase 1 (DUOX1), dual-oxidase 2 (DUOX2), iodotyrosine deiodinase (IYD), solute-carrier (SLC) 26A4, SLC26A7, SLC5A5, TG, and TPO genes. The molecular basis of the CH in 7 families remains unknown. TG mutations were significantly higher on average in the Sudanese population compared with the average number of TG mutations in other populations (P &lt; 0.05). Conclusions All described mutations occur in domains important for protein structure and function, predicting the CH phenotype. Genotype prediction based on phenotype includes low or undetectable thyroglobulin levels for TG gene mutations and markedly higher thyroglobulin levels for TPO mutations. The reasons for higher incidence of TG gene mutations include gene length and possible positive genetic selection due to endemic iodine deficiency.

Thyroid hormone synthesis requires the presence of iodide. The sodium-iodide symporter (NIS) is a glycoprotein that mediates the active uptake of iodide from the blood stream into the thyroid grand. NIS defects due to SLC5A5 gene mutations are known to cause congenital hypothyroidism (CH). The proposita is a 28-year-old female whose origin is North Sudan where neonatal screening for CH is not available. She presented with severe constipation and a goiter at the age of 40 days. Laboratory testing confirmed CH, and she was started on levothyroxine. Presumably due to the delayed treatment, the patient developed mental retardation. Her younger sister presented with a goiter, tongue protrusion, and umbilical hernia, and the youngest brother was also diagnosed with CH based on a thyrotropin level >100 μIU/mL at the age of 22 days and 8 days, respectively. The two siblings were treated with levothyroxine and had normal development. Their consanguineous parents had no history of thyroid disorders. Whole-exome sequencing was performed on the proposita. This identified a novel homozygous missense mutation in the SLC5A5 gene-c.1042T>G, p.Y348D-which was subsequently confirmed by Sanger sequencing. All affected children were homozygous for the same mutation, and their unaffected mother was heterozygous. The NIS protein is composed of 13 transmembrane segments (TMS), an extracellular amino-terminus, and an intracellular carboxy-terminus. The mutation is located in the TMS IX, which has the most β-OH group-containing amino acids (serine and threonine), which is implicated in Na binding and translocation. In conclusion, a novel homozygous missense mutation in the SLC5A5 gene was identified in this Sudanese family with CH. The mutation is located in the TMS IX of the NIS protein, which is essential for NIS function. Low iodine intake in Sudan is considered to affect the severity of hypothyroidism in patients.

BackgroundCongenital hypothyroidism (CH) has an incidence of approximately 1:3000, but only 15% have mutations in the thyroid hormone synthesis pathways. Genetic analysis allows for the precise diagnosis.Case presentationA 3-week old girl presented with a large goiter, serum TSH > 100 mIU/L (reference range: 0.7–5.9 mIU/L); free T4 < 3.2 pmol/L (reference range: 8.7–16 pmol/L); thyroglobulin (TG) 101 μg/L. Thyroid Tc-99 m scan showed increased radiotracer uptake. One brother had CH and both affected siblings have been clinically and biochemically euthyroid on levothyroxine replacement. Another sibling had normal thyroid function. Both Sudanese parents reported non-consanguinity. Peripheral blood DNA from the proposita was subjected to whole exome sequencing (WES). WES identified a novel homozygous missense mutation of the TG gene: c.7021G > A, p.Gly2322Ser, which was subsequently confirmed by Sanger sequencing and present in one allele of both parents. DNA samples from 354 alleles in four Sudanese ethnic groups (Nilotes, Darfurians, Nuba, and Halfawien) failed to demonstrate the presence of the mutant allele. Haplotyping showed a 1.71 centiMorgans stretch of homozygosity in the TG locus suggesting that this mutation occurred identical by descent and the possibility of common ancestry of the parents. The mutation is located in the cholinesterase-like (ChEL) domain of TG.ConclusionsA novel rare missense mutation in the TG gene was identified. The ChEL domain is critical for protein folding and patients with CH due to misfolded TG may present without low serum TG despite the TG gene mutations.Electronic supplementary materialThe online version of this article (10.1186/s12881-018-0588-7) contains supplementary material, which is available to authorized users.

Objective An asymptomatic male was found on screening to have a low serum TSH and total T4. The diagnosis of Graves’ disease was made with positive thyroid stimulating immunoglobulin (TSI) and elevated free T4 in the presence of complete TBG deficiency (TBG-CD). Genetic testing of the patient and family members revealed a novel frameshift mutation in the TBG (SERPINA7) gene resulting in a complete deficiency of the protein. Methods The laboratory testing included total T4, free T4 by analog method and direct dialysis and TBG measurements. Sequencing of genomic DNA was performed from peripheral blood. Results A 35-year-old East Indian male was referred to endocrinology because of abnormal thyroid function tests (TFTs): TSH 0.01 mIU/L (0.4–3.6), total T4 3.0 µg/dl (5.5–10.5) done as part of a “routine office visit”. Upon further testing, the serum free T4 2.0 ng/dl (0.8–1.8) and TSI 355% (<140% baseline) were elevated and the diagnosis of Graves’ disease was made. TBG deficiency was suspected because the total T4 concentration was inconsistent with hyperthyroidism and further testing confirmed TBG was undetectable. Sequencing of the TBG gene revealed a novel hemizygous frameshift mutation: p.Ala64ProfsTer106, TBG-CD Mia (numbering excludes 20 a.a. signal peptide) associated with the complete deficiency of TBG in a patient with Graves’ disease. Conclusion Patients with Graves’ disease harboring a TBG mutation have conflicting TFTs. If a clinically hyperthyroid patient presents with normal or low total T4, serum TBG should be measured to identify an abnormality and prevent unnecessary testing.