Insulin secretion from pancreatic β-cells is the only efficient means to decrease blood glucose concentrations. Glucose is the principal stimulator of insulin secretion with the ATP-sensitive K+ channel-voltage-gated Ca2+ channel-mediated pathway being the primary one involved in glucose-stimulated insulin secretion. Recently, several reports demonstrated that some transient receptor potential (TRP) channels are expressed in pancreatic β-cells and contribute to pancreatic β-cell functions. Interestingly, six of them (TRPM2, TRPM4, TRPM5, TRPV1, TRPV2 and TRPV4) are thermosensitive TRP channels. Thermosensitive TRP channels in pancreatic β-cells can function as multimodal receptors and cause Ca2+ influx and membrane depolarization at physiological body temperature. TRPM channels (TRPM2, TRPM4 and TRPM5) control insulin secretion levels by sensing intracellular Ca2+ increase, NAD metabolites, or hormone receptor activation. TRPV2 is involved not only in insulin secretion but also cell proliferation, and is regulated by the autocrine effects of insulin. TRPV1 expressed in sensory neurons is involved in β-cell stress and islet inflammation by controlling neuropeptide release levels. It is thus clear that thermosensitive TRP channels play important roles in pancreatic β-cell functions, and future analyses of TRP channel function will lead to better understanding of the complicated mechanisms involved in insulin secretion and diabetes pathogenesis.
GH-producing pituitary adenomas frequently co-produce other certain anterior pituitary hormones, such as prolactin (PRL). In contrast, GH-producing adenomas which express all of corticotropin-releasing factor (CRF), urocorin1 (Ucn1) and urocortin3 (Ucn3) have not been reported. A 39-year-old woman was admitted for evaluation of the pituitary tumor. The diagnosis of acromegaly was confirmed by elevated serum GH and IGF-I levels, and the absence of GH suppression by oral glucose tolerance test. ACTH response to desmopressin (DDAVP) was observed (plasma ACTH levels increased from 13.9 to 50.4pg/ml at 90min). Although it is known that ACTH response to DDAVP is considerably useful for the diagnosis of ACTH-dependent Cushing’s syndrome, the diagnosis of Cushing’s disease was not supported by the criteria. The patient underwent transsphenoidal resection of the pituitary tumor. Immunohistological examination confirmed a GH- and PRL-producing adenoma, whereas ACTH was negative. ACTH response to DDAVP disappeared after tumor removal. To determine the cause of preoperative ACTH response to DDAVP, we examined expression of CRF family peptides and vasopressin V1b receptor in the pituitary adenoma by immunohistochemistry. Immunohistochemistry revealed positive immunostaining for CRF, Ucn1, Ucn3 and vasopressin V1b receptor in the adenoma. These observations raised the possibility that DDAVP caused an ACTH response, perhaps via the paracrine effects of tumor-derived CRF and Ucn1. When ACTH response to DDAVP is observed in patients with pituitary tumor, not only the direct effect of DDAVP on ACTH secretion, but also a possible involvement of CRF and/or urocortins expressed in the pituitary adenoma, should be considered.
We report a rare case of recurrent hypoglycemia in a pregnant woman during the period of pregnancies. She suffered from severe hypoglycemia and intrauterine fetal death during the first pregnancy. Thereafter, there was no hypoglycemia, and no obvious cause of hypoglycemia was found by close examinations. Two years later, at eight weeks into the second pregnancy, hypoglycemia recurred. The patient had multiple auto-antibodies including anti-insulin receptor antibody and anti-platelet antibody associated with decreased platelet count. She completed the pregnancy with continuous intravenous administration of glucose that prevented hypoglycemia and finally delivered a healthy baby by Caesarian section. Both the hypoglycemia and thrombocytopenia, and the auto-antibodies disappeared after the delivery. We analyzed the patient’s serum as a possible cause of hypoglycemia. Administration of the serum lowered blood glucose levels of mice more strongly than control serum. In addition, the serum phosphorylated tyrosine of insulin receptor of Chinese hamster ovary cells overexpressing human insulin receptors (CHO-IR cells) in vitro. These results suggest that multiple auto-antibodies might have been induced by a trigger of pregnancy, although the precise mechanism was unclear, and the anti-insulin receptor antibody and anti-platelet antibody might have induced hypoglycemia and thrombocytopenia, respectively, during the pregnancy.
It has been suggested that cytokine release during DKA may result in capillary perturbation and thus may contribute to the development of its acute clinical complications (i.e.cerebral or pulmonary edema). We studied in 38 newly diagnosed T1DM children with DKA, aged 7.68±3.07 years, plasma levels of cytokines IL-1β (interleukin-1β), IL-2, IL-6, IL-8, IL-10, TNF-α (tumour necrosis factor-α) and also WBC (white blood cell count), hs-CRP (high sensitivity C-reactive protein), GH (growth hormone) and cortisol, prior to, during and 120h after DKA management, with the aim to monitor their levels at different time-points and in different degrees of DKA severity. Prior to DKA management the levels of IL-6, IL-8, IL-10, WBC and cortisol were elevated, but were all reduced within 120h after DKA management. Then the patients were divided into two groups: a. moderate/severe: pH≤7.2, b. mild DKA: pH>7.2. In the group with moderate/severe DKA (ph≤7.2), IL-10 levels were the highest of all cytokines, but were significantly decreased after 6h (91.76 vs 18.04 pg/mL, p=0.008), with no further change, while IL-6 levels were decreased at 120h (28.32 vs 11.9 pg/mL, p=0.003). The above were not observed in the group with mild DKA. In conclusion, in the children with DKA of our study, in the group with moderate/severe DKA the IL-10 levels were prematurely reduced at 6 hours, while the IL-6 levels remained high and were reduced at 120 hours after the DKA management. These changes may be responsible for increased capillary perturbation, which could lead to the subsequent development of acute DKA complications.
The main purpose of this study was to investigate whether treatment with long-acting insulin once a day or short-acting insulin three times before each meal daily has a stronger antioxidative effect in patients with type 2 diabetes. These patients had not been treated previously with insulin and were hospitalized for initiation of glycemic control by insulin injection. The patients (n =43) were assigned consecutively and alternately to a group treated with insulin aspart injection three times daily just before each meal and a group treated with insulin detemir injection once daily before bedtime. The results showed that insulin aspart three times a day produced a greater improvement in plasma glucose, and particularly in mean postprandial plasma glucose, compared with insulin detemir once a day (p =0.0006 for comparison of changes between the two insulin treatments). The amount of insulin needed to approach the target levels of plasma glucose was larger in the insulin aspart group (26.0 ± 10.7 U/day vs. 13.7 ± 4.9 U/day; p <0.0001). However, only insulin detemir significantly decreased oxidative stress evaluated based on the level of urinary 8-iso-prostaglandin F2α (p =0.0079), although the mechanisms are not fully evident.
The association between subclinical hypothyroidism (SCH) and microvascular complications of type 2 diabetes is unclear. We examined whether SCH is associated with diabetic retinopathy or nephropathy in Korean patients with type 2 diabetes. Data from 489 patients who visited the diabetes clinic at a university hospital between 2001 and 2007 were analyzed retrospectively. Participants were evaluated for glycemic control, thyroid function, and diabetic retinopathy and nephropathy. Diabetic retinopathy was classified into five grades. Diabetic nephropathy was assessed by the presence of albuminuria. Patients in the SCH group had a higher proportion of women, older age, longer duration of diabetes, higher systolic and diastolic blood pressure, and higher insulin resistance index compared with the euthyroid group. No significant difference in family history of diabetes or body mass index was found between groups. The prevalence of severe diabetic retinopathy (severe nonproliferative diabetic retinopathy or proliferative diabetic retinopathy) was significantly higher in the SCH group than the euthyroid group (32.8% vs. 19.6%, P = 0.036), whereas no between-group difference was found in the prevalence of diabetic nephropathy. After adjustment for potential confounding factors (HbA1c, BMI, duration of diabetes, diabetic nephropathy, and hypertension) by multivariate logistic regression analysis, SCH remained significantly associated with severe diabetic retinopathy (odds ratio 2.086 (95% CI, 1.010-4.307), P = 0.047). These results suggest that SCH was independently associated with severe diabetic retinopathy in patients with type 2 diabetes. Further prospective studies are required to confirm the association between SCH and diabetic retinopathy.
Chronic pain is a common problem in clinical practice and women are affected more often than men. Morphine is often used for long-term pain relief, but it induces side effects including endocrine alterations. The aim of the present study was to assess the behavioural and hormonal effects of transdermal buprenorphine in women suffering from persistent non-malignant pain. Hormones (LH, FSH, total and free testosterone, estradiol, cortisol) and pain measures (visual analogue scale, McGill Pain questionnaire, present pain intensity test) were evaluated at baseline and after 1, 3 and 6 months. Subjects were recruited in the Second University of Naples Pain Research Centre. Eighteen chronic pain women were included in the study, divided into pre- and post-menopausal groups. A transdermal buprenorphine patch (Buprenorphine TDS, 35 μg/h) was administered every 72 h. As expected, buprenorphine administration led to a decrease in pain intensity and no side effects suggestive of hypogonadism were recorded. Pain measures decreased at the first control visit (T1) in both groups. Total and free testosterone were not reduced by treatment (they tended to increase in both groups) while cortisol progressively recovered from the quite low levels detected at the beginning of treatment. These data confirm that buprenorphine is a safe and effective drug for pain relief in women. It is free from the adverse effects on gonadal hormones frequently associated with other opioid treatments. The lack of opioid-induced effects on gonadal hormones (i.e. hypogonadism) is important to guarantee safe long-term pain treatment.
β2 and β3 adrenergic receptors (β2AR, β3AR) and uncoupling protein 1 (UCP1) have been considered as candidate genes for obesity. Although each polymorphism of β3AR Trp64Arg, β2AR Arg16Gly and UCP1 -3826A>G is known to be associated with obesity, the interaction among these polymorphisms is not fully understood. We analyzed β3AR Trp64Arg, β2AR Arg16Gly and UCP1 -3826A>G polymorphisms by the Smart Amplification Process 2 in 222 Japanese subjects without the medication of hypertension, dyslipidemia or diabetes, and investigated the association between the physical and metabolic characteristics and the combination of these polymorphisms. In analysis of the genotypes combination, only the carriers of both β2AR Arg/Arg and UCP1 G/G genotypes had significantly higher waist to hip ratio (p=0.014). In analysis of the alleles combination, a significant difference was observed in waist to hip ratio among the groups stratified by the carrying number of the alleles of β3AR Arg, β2AR Arg and UCP1 G (p=0.026), and the waist to hip ratio was significantly higher in the carriers of four and five risk alleles than in the carriers from zero to three risk alleles (p=0.005). The present study demonstrated the interaction among β3AR Trp64Arg, β2AR Arg16Gly and UCP1 -3826A>G for the accumulation of visceral fat.
To know the longitudinal shift of blood IGF-1 of cured acromegaly, we conducted retrospective survey of changes in blood IGF-1 over two years, which has not been previously investigated. Blood IGF-1 levels were measured for longer than 2 years after TSS in 37 patients whose nadir GH during postoperative oral glucose tolerance test (OGTt) was under 1 ng/mL. Blood IGF-1 very gradually declined after three months; 230.6 (mean) ng/mL at 3-12 months, 202.3 ng/mL at 12-24 months, and 198.6 ng/mL at 24-36 months. Their SD values, calculated based on standard IGF-1 values of age- and sex-matched Japanese population, also slowly decreased after three months; 1.69 (mean) at 3-12 months, 1.23 at 12-24 months, and 1.12 at 24-36 months. Very slow decrease of the IGF-1 levels continued beyond the first several months and even the first year after TSS. The declination of values is greater than that associated with aging. This declination may be at least partially a reflection of the slow decrease and late normalization of GH secretion.
Papillary thyroid carcinoma (PTC) is characterized by extensive lymph node metastases. A considerably high frequency of lymph node metastases in the upper mediastinal compartment (UMC) has been reported. However, the significance of prophylactic upper mediastinal lymph node dissection (UMLND) by sternotomy as an appropriate therapeutic option has not yet been clarified. Thirty-three patients who underwent prophylactic UMLND by sternotomy for PTC at our institution between 1980 and 1987 (group A) were analyzed. One hundred and fifty-one consecutive patients with PTC who underwent curative total thyroidectomy, bilateral modified radical neck dissection, and UMLND by collar incision as initial treatment between 1990 and 1999 (group B) were analyzed as controls. The patterns of lymph node metastases in the cervical compartment of these two groups were comparable; distribution of lymph node metastases in UMC was considerably less frequent than in other compartments. Clinical relapse in UMC was not observed in both groups. No significant difference in disease specific survival or relapse free survival between group A and B was observed. The lack of clinical relapse in UMC in group B indicates that most of the lymph node metastases in this compartment could be resected by the conventional collar incision or most microscopic lymphatic metastases could remain dormant as with lateral microscopic node metastases. Thus, upper mediastinal lymph node metastases requiring sternotomy to resect in curable patients with PTC could be less frequent. Prophylactic UMLND by sternotomy for PTC is discouraged from a clinical view point.
We employ rapid-ACTH stimulation test under dexamethasone (DEX) suppression to assess the adrenal function in daily clinic. However, we have little knowledge about the excretion of urinary free cortisol (FF) and cortisone (FE) in pooled urine in this setting. The purpose was to examine the changes of FF and FE as well as FF/FE ratio in pooled urine after rapid-ACTH stimulation test under DEX suppression using stable isotope dilution - gas chromatography/mass spectrometry (SID-GC/MS). Pooled urine samples were collected from 8 patients (age 33-71 years) who were suspected to have primary aldsteronism. They all were finally diagnosed as having normal glucocorticoid secretion. We performed rapid-ACTH stimulation test with DEX suppression for consecutive 4 days as follows. (1) 24 hour urine samples were serially collected from 2300h on day 1 for 72 hours (Basal, DEX1mg, and DEX8mg-ACTH). (2) 1 and 8 mg DEX was given at 2300h on day 2 and 3, respectively. (3) 250μg of ACTH was given at 0900h on day 4. Urine free steroids were delivered with bismethylenedioxy-heptafluorobutyric anhydride and analyzed by SID-GC/MS (μg/day). From DEX1mg to DXE8mg-ACTH, 1) FF and FE were significantly increased (3.9±1.3 to 21.3±14.6 and 12.4±4.8 to 26.1±11.0 μg/day, respectively), but 2) FF/FE ratio significantly increased (0.32±0.05 to 0.77±0.23). These data suggested that newly synthesized cortisol by ACTH stimulation was not efficiently metabolized to cortisone.