Over 100 years have passed since insulin was first administered to a diabetic patient. Since then great strides have been made in diabetes research. It has determined where insulin is secreted from, which organs it acts on, how it is transferred into the cell and is delivered to the nucleus, how it orchestrates the expression pattern of the genes, and how it works with each organ to maintain systemic metabolism. Any breakdown in this system leads to diabetes. Thanks to the numerous researchers who have dedicated their lives to cure diabetes, we now know that there are three major organs where insulin acts to maintain glucose/lipid metabolism: the liver, muscles, and fat. The failure of insulin action on these organs, such as insulin resistance, result in hyperglycemia and/or dyslipidemia. The primary trigger of this condition and its association among these tissues still remain to be uncovered. Among the major organs, the liver finely tunes the glucose/lipid metabolism to maintain metabolic flexibility, and plays a crucial role in glucose/lipid abnormality due to insulin resistance. Insulin resistance disrupts this tuning, and selective insulin resistance arises. The glucose metabolism loses its sensitivity to insulin, while the lipid metabolism maintains it. The clarification of its mechanism is warranted to reverse the metabolic abnormalities due to insulin resistance. This review will provide a brief historical review for the progress of the pathophysiology of diabetes since the discovery of insulin, followed by a review of the current research clarifying our understanding of selective insulin resistance.

GH activates GH receptors, which activates IGF-1 in the liver through a cascade of processes. The GH/IGF-1 axis plays an important role in the regulation of metabolism. Insufficient GH secretion results in short stature in childhood, while adult GH deficiency (AGHD) is observed in adulthood. The early diagnosis of AGHD is important for early initiation of GH replacement therapy. This review described the regulatory mechanisms of GH signaling based on nutritional status and a novel disease concept pathogenesis that causes AGHD. GH-dependent IGF-1 production in the liver is regulated by a complex interplay between nutritional status, hormones, and growth factors. GH resistance is an adaptive response that enhances survival during starvation and malnutrition. Sirtuin 1 (SIRT1) negatively regulates GH-induced IGF-I production in the liver by directly inhibiting STAT5 activation, which causes GH resistance under starvation and malnutrition. The presence of autoantibodies is strongly associated with the disruption of immune tolerance in pituitary cells. Pituitary-specific transcription factors (PIT-1) are essential for the development, differentiation, and maintenance of GH, PRL, and TSH producing cells. However, the underlying mechanism that causes immune intolerance to PIT-1 remain unclear. The GH-IGF-1 system plays a pivotal role in growth, and the involvement of SIRT1 in this regulatory mechanism presents an intriguing perspective on the interplay between nutrient metabolism and lifespan. The discovery of the anti-PIT-1 pituitary antibody, a novel disease concept associated with AGHD, has provided valuable insights, which serves as a significant milestone towards unraveling the complete pathogenesis of the disease.

Primary caregivers of children with type 1 diabetes mellitus (T1DM) are prone to negative emotions. This study explored the anxiety status of the caregivers and analyzed the related factors. In this prospective study, 245 primary caregivers of T1DM children who were reexamined in the outpatient clinic of Children’s Hospital affiliated to Zhengzhou University between April 2020 and Sep 2022 were surveyed with a questionnaire and the Hamilton Anxiety Rating Scale (HAMA). The detection rate of anxiety symptoms in T1DM primary caregivers was 21.2%, with a total score of HAMA score of 11.74 ± 2.50. There were significant differences between the anxiety and non-anxiety groups in treatment method, HbA1C to standard (≤7.0%), severe hypoglycemia in the last 1 year and the number of adolescent cases (χ² = 15.798, p = 0.000; χ² = 4.197, p = 0.040; χ² = 5.291, p = 0.021; χ² = 14.279, p = 0.000). Multivariable logistic regression analysis showed that insulin pump treatment, HbA1C to standard (≤7.0%) and adolescence were associated with anxiety in primary caregivers (OR = 4.040, 95%CI 1.969–8.289, p = 0.000; OR = 0.472, 95%CI 0.237–0.955, p = 0.037; OR = 2.952, 95%CI 1.495–5.831, p = 0.002). Pediatric endocrine care should pay more attention to the anxiety of the caregivers of adolescent T1DM children treated with insulin pumps while helping the children manage their disease.

Late-onset hypogonadism is generally treated with testosterone replacement treatment. However, the efficacy rate of treatment for patients with low testosterone is not clear because patients without low testosterone are also treated in real-world clinical settings. This study comprised 110 men with low testosterone concentration of <3.0 ng/mL who underwent testosterone replacement treatment. Physical factors, laboratory and endocrinologic profiles, and scores of several questionnaires were assessed. Testosterone replacement treatment was performed with intramuscular injection of 250 mg of testosterone esters every 2–4 weeks, and efficacy was judged by patient satisfaction. After confirming efficacy, changes in several factors by the treatment were evaluated. Finally, the comparison between evaluation by patient satisfaction and by that with the questionnaires was assessed. Among the 110 patients, 77 (70.0%) were satisfied with the treatment, which was effective in 65.7%, 71.4%, and 73.1% of patients with mental, physical, and sexual dysfunction, respectively. The questionnaire scores including the Aging Males Symptoms rating scale were significantly improved in both the satisfaction and non-satisfaction group. However, no significant differences in the amount of change in questionnaire scores were found for all questionnaire scores improved by testosterone replacement treatment between the groups. Patient satisfaction was not associated with improvement of the Aging Males Symptoms score. Although testosterone replacement treatment was effective for 70.0% of the hypogonadal patients, patient satisfaction did not correlate with improvement of questionnaire scores. We concluded that not only questionnaire results but also patient satisfaction is important when evaluating efficacy in patients undergoing testosterone replacement treatment.

Haemoglobin A1c (HbA1c) variability, a metric reflecting long-term glycaemic fluctuation, is associated with macrovascular events in type 2 diabetes. We aimed to investigate the impacts of HbA1c variability on preclinical atherosclerosis in patients without prior cardiovascular disease. We conducted a cross-sectional study on 564 participants with diabetes who underwent general health checkups from 2016–2022. At least three HbA1c measurements were conducted for each patient. Carotid intima-media thickness (CIMT) and plaque were evaluated by B-mode ultrasonography on bilateral carotid common arteries. The standard deviation (SD) and coefficient of variance (CV) of HbA1c were calculated. We found that each doubling in CV-HbA1c and SD-HbA1c was associated with a significant increment in CIMT. The effects were more pronounced in the groups with higher mean-HbA1c (mean-HbA1c ≥6.5%). The odds ratio (95% confidence interval) for the carotid plaque was 2.68 (1.57, 4.56) and 2.88 (1.16, 5.13) in the third tertile of CV-HbA1c and SD-HbA1c respectively after fully adjusting for all the conventional risk factors in the multivariable logistic regression analysis. High mean-HbA1c plus the third tertile of HbA1c variability sharply increased the prevalence of carotid plaques. In conclusion, HbA1c variability was independently associated with CIMT and plaques in populations with diabetes. CV-HbA1c and SD-HbA1c had more effects on subclinical atherosclerosis in patients with poorly-controlled blood glucose levels.

Active surveillance (AS) is an accepted management option for patients with low-risk papillary thyroid microcarcinoma (PTMC), although some patients undergo immediate surgery (IS). At surgery, patients may have risky features such as adhesion or invasion to the adjacent organs. The surgical outcomes of this subset of patients are unknown. Here, we investigated the surgical and oncological outcomes of these patients in comparison with others. Between 2005 and 2019, 4,635 patients were diagnosed with low-risk PTMC at our institute. Of these, 1,739 patients underwent IS. In total, 114 patients had risky features at surgery (risky feature group), while the remaining 1,625 did not (no-risky feature group). The median follow-up periods in the risky and no-risky feature groups were 8.5 and 7.6 years, respectively. The risky feature group had higher incidences of tracheal invasion (8.8%), recurrent laryngeal nerve invasion (RLN) (7.9%), and permanent vocal cord paralysis postoperatively (10.0%) and higher frequency of pathological lateral lymph node metastasis (6.1%) than the no-risky feature group (0%, 0%, and 0.2%, and 0%, respectively [p < 0.01]). However, unexpectedly, the former had a lower incidence of high Ki-67 labeling index (1.1%) and lower locoregional recurrence rate (0%) than the latter (8.3% and 0.7, respectively [p < 0.01], not calculable). None of the groups developed distant metastasis or died of the disease. The risky feature group required resection of the trachea and/or the RLN more often than the no-risky feature group. However, unexpectedly, the tumor growth activity in the risky feature group was low, and their oncological outcome was excellent.

The remodeling of skeletal muscle extracellular matrix (ECM) components is related to the degree of insulin resistance (IR). Membrane receptors such as integrins provide two-way signaling (“inside-out” and “outside-in” signaling) between ECM components of skeletal muscle (e.g., collagen, laminin, fibronectin) and intracellular signaling pathways. The aim of the study was to analyze the relationship between the expression of integrins in skeletal muscle and insulin sensitivity (IS) in young, healthy, non-obese volunteers. We studied 36 healthy non-obese male participants. Subjects were divided into three subgroups on the basis of the hyperinsulinemic-euglycemic clamp: upper IS tertile, medium IS tertile, and lower IS tertile. Vastus lateralis muscle biopsies were performed before each clamp. Next, analysis of integrin mRNA expression was performed. Waist circumference, percent body fat, fasting serum insulin, total cholesterol, triglycerides and LDL-cholesterol were higher in the lower IS tertile subgroup compared to the other two subgroups (p < 0.05). The lower IS tertile showed increased expression of ITGA5, ITGA6, ITGA7, SPARC (p < 0.05) in comparison with the upper IS tertile and ITGA6 (p < 0.05) compared to the medium IS tertile. ITGA2, ITGA3, ITGA5, ITGA6, ITGA7, SPARC correlated inversely with IS (p < 0.05). Skeletal muscle integrin are associated with low IS in healthy nonobese men. Our data suggest that factors associated with ECM in muscle may be involved in modulation of insulin action even at the early stages of the development of IR.

Hyperkalemia is developed in a part of patients with aldosterone-producing adenoma (APA) after adrenalectomy, suspected to be due to the insufficiency of aldosterone secretion. The purpose of this study is to determine the frequency and characteristics of prolonged postoperative hypoaldosteronism (PPHA) using chemiluminescent enzyme immunoassay (CLEIA). We studied 58 patients with APA with long time after adrenalectomy and whose PAC was measured using a CLEIA kit. The PAC value measured using CLEIA was significantly lower than that of using RIA between two consecutive visits before and after the shift of measuring method of PAC (median [interquantile range], 123.0 [99.8–164.0] vs. 39.5 [15.8–64.2] pg/mL, p < 0.01). PAC was below the minimum limit of quantification (4.0 pg/mL) of the CLEIA kit at least once in nine patients (15.5%) who had PPHA. The PPHA group were older (mean ± standard deviation, 61.3 ± 8.5 vs. 50.5 ± 10.1 years, p < 0.01) and had lower eGFR (60.3 ± 14.0 vs. 82.3 ± 22.8 mL/min/1.73 m², p < 0.01) than the non-PPHA group. The frequency of postoperative hyperkalemia (maximum serum potassium >5.5 mEq/L) was higher in the PPHA group than in the non-PPHA group (55.6% vs. 8.2%, p < 0.01). In conclusion, a few patients with APA long time after adrenalectomy had unmeasurable PAC using CLEIA. PPHA is likely to develop in patients with APA after adrenalectomy who are older and have impaired renal function. Additionally, PPHA is related to the occurrence of postoperative hyperkalemia.

The age-dependent decrease in muscle mass and function is known as sarcopenia. The risk of sarcopenia is higher in patients with diabetes, and assessment of muscle mass and function is especially important in patients with diabetes. Recent reports suggest that the phase angle (PhA), which is obtained from bioelectrical impedance analysis (BIA), may be a good marker of not only muscle mass but also muscle function in healthy people. However, the clinical significance of PhA in patients with diabetes has not been fully investigated. Therefore, we evaluated the association of PhA with muscle mass, muscle strength, and physical performance in 159 patients with type 2 diabetes (male 102; female 57) aged 40 to 89 years. We measured PhA and appendicular skeletal muscle index (SMI) by BIA and handgrip and leg extension strength and performed the Short Physical Performance Battery (SPPB). In a simple correlation analysis, both right and left PhA correlated with SMI, handgrip and leg extension strength, and SPPB score, and in multiple regression analysis, PhA on each side correlated with SMI and ipsilateral handgrip strength. These data suggest that PhA may be a useful marker of muscle mass, muscle strength, and physical performance in patients with type 2 diabetes. A large-scale prospective study should be performed to confirm the results and clarify the clinical usefulness of PhA in patients with diabetes.

Although rare, endogenous hypercortisolemia, including Cushing’s disease (CD), is known to cause bowel perforation and to mask typical symptoms of bowel perforation, leading to delayed diagnosis. Additionally, elderly patients with CD are considered to be at a higher risk for bowel perforation because intestinal tissue fragility tends to increase in the elderly. Herein, we describe a rare case in which a young adult patient with CD was diagnosed with bowel perforation associated with CD following severe abdominal pain. A 24-year-old Japanese man was admitted to the hospital for the evaluation of ACTH-dependent Cushing’s syndrome. He suddenly complained of severe abdominal pain on the 8th day of hospitalization. Computed tomography revealed free air around the sigmoid colon. The patient was diagnosed with bowel perforation, underwent emergency surgery, and was saved. He was subsequently diagnosed with CD, and the pituitary adenoma was resected transsphenoidally. To date, eight cases of bowel perforation due to CD had been reported, with a median age of 61 years at the time of bowel perforation. Hypokalemia was detected in half of the patients, and all had a history of diverticular disease. Nevertheless, not many patients complained of peritoneal irritation. In conclusion, this is the youngest reported case with bowel perforation due to CD and the first report of bowel perforation in a patient without a history of diverticular disease. Bowel perforation may occur in patients with CD, irrespective of age and the presence of hypokalemia, diverticular disease, or peritoneal irritation.