Effects of a sodium glucose co-transporter 2 selective inhibitor, ipragliflozin, on the diurnal profile of plasma glucose in patients with type 2 diabetes: A study using continuous glucose monitoring.

AIMS/INTRODUCTION: To assess the effects of sodium glucose co-transporter 2 inhibitor therapy on the pathophysiology of type 2 diabetes. MATERIALS AND METHODS: We administered ipragliflozin to 21 inpatients with type 2 diabetes for 7 days, and analyzed the diurnal profiles of plasma glucose and 3-hydroxybutyrate. A total of 21 age-, sex- and body mass index-matched diabetic patients served as controls. RESULTS: Continuous glucose monitoring showed that the 24-h glucose curve was shifted downward without hypoglycemia by the administration of ipragliflozin. The average glucose level was reduced from 182 ± 54 mg/dL to 141 ± 33 mg/dL (P < 0.0001). The magnitude of the reduction was highly correlated with the baseline average glucose level. Homeostasis model assessment of insulin resistance was decreased, and homeostasis model assessment of ß-cell function was increased during the treatment. Urinary glucose excretion was correlated with the average glucose level both on day 0 and on day 7, although the regression line was steeper and shifted leftward on day 7. The ipragliflozin-treated patients lost more weight than the control patients (1.4 ± 0.5 vs 0.5 ± 0.6 kg, P < 0.0001). Plasma levels of 3-hydroxybutyrate were significantly increased with peaks before breakfast and before dinner. Patient age and bodyweight loss were negatively and positively correlated with the peak levels of 3-hydroxybutyrate on day 7, respectively. CONCLUSIONS: The ipragliflozin treatment improved the 24-h glucose curve without causing hypoglycemia. The close correlation between the magnitude of glucose reduction and the baseline plasma glucose concentration suggests that the risk of hypoglycemia is likely low. It might be prudent to monitor ketone body levels in younger patients and in patients with rapid weight loss.

Distinct pharmacodynamics of insulin glargine and insulin detemir: crossover comparison in Type 1 and Type 2 diabetic patients on basal-bolus regimen.

We compared blood glucose profile when glargine or detemir was injected once daily before dinner in combination with pre-meal insulin lispro by a crossover design. Glargine showed lower post-dinner and bedtime glucose levels in Type 1 diabetes, and lower pre-dinner and post-dinner glucose levels in Type 2 diabetes than detemir.

Associations of protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene polymorphisms with susceptibility to Graves' disease in a Japanese population.

BACKGROUND: The polymorphism of the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene, which encodes an important negative regulator of T cell activation, has been reported to be associated with susceptibility to Graves' disease (GD) in Caucasians. The objective of this study was to investigate whether PTPN22 gene polymorphisms confer susceptibility to GD and Graves' ophthalmopathy (GO) in a Japanese population. METHODS: We performed a case-control study of PTPN22 gene polymorphisms in Japanese GD patients (n = 414) and healthy control subjects with no antithyroid autoantibodies or family history of autoimmune disorders (n = 231). The G-1123C polymorphism (rs2488457) in the promoter region, Arg620Trp (C1858T) polymorphism (rs2476601) in exon 14, IMS-JST146695 polymorphism (rs3789607) in intron 19, and SNP37 (rs3789604) downstream of the PTPN22 gene were determined by polymerase chain reaction (PCR)-restriction fragment length polymorphism using restriction enzymes and direct PCR sequencing methods. RESULTS: None of the GD patients or control subjects had the 1858T allele of the PTPN22 gene polymorphism. The AA-genotype and A-allele frequencies of SNP37 were significantly higher in GD patients than in control subjects (A-allele frequency: p = 0.0085, odds ratio = 1.45). The genotype frequencies and allele frequencies of the G-1123C and IMS-JST146695 polymorphisms did not differ between GD patients and control subjects. The -1123G/1858C/JST146695T/SNP37C haplotype frequency was significantly lower in GD patients than in control subjects. There were no associations between PTPN22 gene polymorphisms and GO. CONCLUSIONS: The results suggest that SNP37 of the PTPN22 gene is associated with susceptibility to GD in a Japanese population. Further studies including functional analyses are required.

Autoimmune hypophysitis treated with intravenous glucocorticoid therapy.

A 46-year-old man presented with frontal headache, a visual field defect and general fatigue. Magnetic resonance imaging (MRI) of the brain showed symmetrical enlargement of the pituitary gland and stalk due to the presence of a mass lesion extending toward the optic chiasm. Gadolinium injection further revealed homogeneous strong enhancement with involvement of the adjacent dura (dural tail). Basal plasma levels of ACTH, free thyroxine and gonadotropins were decreased, and 24-h urinary 17-OHCS excretion was reduced. An elevated anti-thyroglobulin antibody titer indicated the presence of autoimmune thyroiditis. Under the suspicion of autoimmune hypophysitis, 60 mg/day prednisolone sodium succinate was intravenously administered for two weeks followed by a decreasing dose of oral prednisolone. Clinical symptoms and pituitary dysfunction recovered during steroid treatment and MRI showed marked shrinkage of the pituitary mass. Early initiation of an intravenous dose of glucocorticoid followed by oral steroid administration therefore seems to be an efficient treatment for autoimmune hypophysitis even in patients with visual dysfunction.

Interleukin-12B gene polymorphism does not confer susceptibility to Graves' ophthalmopathy in Japanese population.

Graves' disease (GD) is an autoimmune disorder with genetic predisposition and frequently associated with Graves' ophthalmopathy (GO). Interleukin 12 (IL-12) is an important mediator of inflammatory immune responses and is expressed in the thyroid and orbit. IL-12B gene, which encodes the p40 subunit of IL-12, is located at chromosome 5q31-33. The aim of the present study was to investigate whether IL-12B gene polymorphism is associated with the development of GD or GO. IL-12B gene polymorphism was studied in Japanese GD patients (n = 329) and healthy control subjects without anti-thyroid autoantibodies or a family history of autoimmune disorders (n = 226). The A/C polymorphism at position 1188 of the 3' untranslated region (3'UTR) of the IL-12B gene was analyzed using the polymerase chain reaction--restriction fragment length polymorphism method. There was no difference in allele or genotype frequency of the IL-12B gene polymorphism (1188A/C) between GD patients and control subjects. There was no association of the IL-12B gene polymorphism with ophthalmopathy, severity of hyperthyroidism or serum IgE levels. There was no association of the IL-12B gene polymorphism with serum IL-12 levels, which were significantly elevated in hyperthyroid phase of GD. In conclusion, IL-12B gene 1188A/C polymorphism is not associated with GD or GO susceptibility in Japanese.

Lack of association of interleukin-18 gene polymorphisms with susceptibility of Japanese populations to Graves' disease or Graves' ophthalmopathy.

OBJECTIVE: To investigate whether polymorphisms of interleukin (IL)-18 gene confer susceptibility to Graves' disease (GD) and Graves' ophthalmopathy (GO). DESIGN: We performed a case control study on polymorphisms of IL-18 gene in Japanese patients with GD (n = 435), and healthy control subjects without antithyroid autoantibodies or family history of autoimmune disorders (n = 255). The C-4675G, C-607A, and G-137C polymorphisms in the promoter region and A105C (exon 5) polymorphism were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) using restriction enzymes, sequence-specific PCR, and PCR-direct sequencing methods. RESULTS: None of the polymorphisms in the IL-18 gene were associated with development of Graves' disease. The CC genotype and C allele frequencies of IL-18 gene G-137C polymorphism tended to be greater in patients with ophthalmopathy than in patients without evident ophthalmopathy. However, the differences were not statistically significant. Although there were three major haplotypes, none of the haplotypes were statistically associated with susceptibility to GD or ophthalmopathy. CONCLUSIONS: These results suggest that IL-18 gene polymorphisms are not major genetic factors for susceptibility to GD in a Japanese population. Further studies with adequate sized data set in the subset analyses for GO are needed.

A C/T polymorphism in the 5' untranslated region of the CD40 gene is associated with later onset of Graves' disease in Japanese.

Graves' disease (GD) is an autoimmune disorder with genetic predisposition. CD40, which stimulates lymphocyte proliferation and differentiation, is an important immunomodulator and is expressed in the thyroid follicular cells as well as antigen-presenting cells. A single nucleotide polymorphism (SNP) at position -1 of the Kozak sequence of the CD40 gene has been reported to be associated with the development of GD. The aim of the present study was to investigate whether CD40 gene polymorphism confers susceptibility to GD in Japanese. CD40 gene polymorphisms were studied in Japanese GD patients (n = 324) and healthy control subjects without anti-thyroid autoantibodies or a family history of autoimmune disorders (n = 229). A C/T polymorphism at position -1 of the CD40 gene was measured using the polymerase chain reaction restriction fragment length polymorphism. There was no significant difference in allele or genotype frequency of the CD40 SNP between GD and control subjects. There was a significant decrease in the TT genotype frequency in the GD patients, who developed GD after 40 years old, than those under 40 year of age. These data suggest that the SNP of CD40 gene is associated with susceptibility to later onset of GD in Japanese.

Interleukin-13 gene polymorphisms confer the susceptibility of Japanese populations to Graves' disease.

Graves' disease (GD) is an autoimmune disorder with genetic predisposition. IL-13 is an important mediator of antiinflammatory immune responses and is expressed in the thyroid and orbit. The aim of the present study was to investigate whether IL-13 gene polymorphisms are associated with the development of GD. IL-13 gene polymorphisms were studied in Japanese GD patients (n = 310) and healthy control subjects without antithyroid autoantibodies or a family history of autoimmune disorders (n = 244). A C/T polymorphism at position -1112 of the promoter region was measured using the direct sequencing method, and an Arg(130)Gln (G2044A) polymorphism in exon 4 was examined using the PCR-restriction fragment length polymorphism method. There was a significant decrease in -1112T allele frequency in GD patients compared with controls (16% vs. 23%; P = 0.0019). The frequency of the 2044A allele on exon 4 also appeared lower in GD patients compared with controls. Haplotype analysis showed a significant decrease in the -1112T/2044A haplotype in GD patients. There was no association between IL-13 gene polymorphisms and ophthalmopathy, severity, or serum IgE levels. In conclusion, IL-13 gene polymorphisms are associated with GD susceptibility in Japan.

Immunohistochemical analysis of bcl-2, Bax and Bak expression in thyroid glands from patients with Graves' disease.

In order to clarify the role of apoptosis and the expression of Bcl-2 family proteins in the pathology of Graves' disease (GD), we evaluated the apoptosis by in situ end-labeling of fragmented DNA and the expression of Bcl-2, Bax and Bak by immunohistochemistry in thyroid tissues from 20 patients with GD and in normal thyroid tissues from 6 patients with follicular adenoma (N). Apoptotic nuclei were found in thyrocytes and in germinal center of lymphoid follicles. Bcl-2 was strongly expressed in both GD and N thyrocytes. Bax was not expressed in either GD or N thyrocytes. Bak was expressed in thyrocytes from 5 of 20 patients with GD, while it was detected in all N thyrocytes. In lymphoid follicles Bcl-2 was expressed in the mantle zone, while Bax and Bak were both expressed in the germinal center. The percentage of apoptotic nuclei in GD thyrocytes was low (0~3.6%), and negatively correlated with the weight of the thyroid glands resected (rs = -0.43, P<0.05). It was greater in Bak-positive GD thyrocytes than in Bak-negative ones (mean +/- SD; 1.7 +/- 0.7% vs. 0.7 +/- 0.9%, P<0.05). These findings suggest that the differential expression of Bcl-2 family proteins in both thyrocytes and lymphoid follicles may be involved in the pathology of GD.

A polymorphism of interferon-gamma gene associated with changes of anti-thyrotropin receptor antibodies induced by antithyroid drug treatment for Graves' disease in Japanese patients.

Graves' disease (GD) is an autoimmune disorder with genetic predisposition. Interferon-gamma (IFN-gamma) is an important mediator of inflammatory and immune responses. The aim of the present study was to investigate whether the polymorphism of IFN-gamma gene is associated with the development of GD or with clinical course during the antithyroid drug therapy. We have studied the CA repeat polymorphisms in the first intron of IFN gamma gene in Japanese patients with GD (n = 162) and healthy control subjects without antithyroid autoantibodies or family history of autoimmune disorders (n = 133). There was no difference in allele frequency of IFN-gamma gene polymorphism between patients with GD and control subjects. However, the allele 4 (15 CA repeats) frequency was significantly greater in patients whose antithyrotropin receptor antibody (TRAb) became negative within 3 years by antithyroid drug treatment than those with consistently positive TRAb for more than 3 years (34.1% vs. 15.7%, chi2 = 8.545, p = 0.0035, pc = 0.049). The in vitro production of IFN-gamma by concanavalin A-stimulated peripheral blood mononuclear cells was significantly smaller in control subjects with the allele 4 compared to those with the other alleles. In conclusions, the CA repeat polymorphism of the IFN-gamma gene might be associated with the outcome of anti-thyroid drug treatment.

Technetium-99 m sestamibi imaging in patients with subacute thyroiditis.

To determine if subacute thyroiditis (SAT) is associated with changes in the regional perfusion of the thyroid gland, we performed Tc-99 m sestamibi scans on eleven patients with SAT who had painful goiter and clinical thyrotoxicosis. Eleven patients had Tc-99 m pertechnetate and Tc-99 m sestamibi scintigraphy during the acute stage of SAT. The thyroid uptake ratio of sestamibi was compared with the laboratory data and color Doppler ultrasonography. Tc-99 m pertechnetate scintigraphy in the thyroid was markedly reduced during the acute stage of SAT. Conversely, Tc-99 m sestamibi showed diffuse increased uptake in the thyroid region, suggesting increased perfusion. On the other hand, there was near absence of vascularization in the acute phase and slight increase in the recovery phase by color Doppler ultrasonography. The clearance rate of Tc-99 m sestamibi during the early phase (from 10 min to 1 h) was decreased in the acute stage of SAT. The sestamibi uptake ratio correlated with serum immunosuppressive acidic protein (IAP) in the acute stage of SAT and the sestamibi uptake ratio in the recovery stage of SAT was correlated with serum thyrotropin levels. Tc-99 m sestamibi uptake in the early phase in the acute stage of SAT may reflect the inflammatory process associated with SAT.

Role of cytokines in the pathogenesis of thyroid-associated ophthalmopathy.

Thyroid-associated ophthalmopathy (TAO) is generally considered to be an autoimmune disorder associated with Graves' disease. However, the nature of autoantigen or mechanism of the development of ophthalmopathy remains unclear. In the present review we focus the accumulating evidence on roles of cytokines in the orbital tissues from patients with TAO and animal models. From the analysis of T-cell clones, T helper 1 (T(H)1)-like clones were predominant in cultures from patients with recent onset hyperthyroidism and T(H)2-like clones were predominant in culture form patients with more remote onset hyperthyroidism. T(H)1-like cytokine profiles are predominant in eye muscle tissue and related to the eye muscle enlargement, while T(H)2-like cytokine profiles are predominant in orbital fat tissue from patients with TAO and negatively related to orbital volume. Therefore, T(H)1-like cytokines, proinflammatory cytokines, may play a role on the development of eye muscle component of TAO in the acute stage. T(H)2-like cytokines, anti-inflammatory cytokines, may play protective role in the chronic stage of TAO. The studies using animal models suggest the genetic background is involved in the pathogenesis of TAO. The studies on polymorphism of the cytokine genes support the proinflammatory role of T(H)1-like cytokines and protective role of T(H)2-like cytokines.