A Case of Acromegaly With Progressed Diabetic Retinopathy and Sarcopenia Diagnosed Following the Onset of Severe Hypoglycemia.

Acromegaly is a rare disorder characterized by excessive production of growth hormone (GH) from a pituitary tumor, typically leading to elevated glucose levels due to increased insulin resistance; hypoglycemia is rare. However, the long-term effect of excess GH on the peripheral organs is still unclear. Here we present a 69-year-old man evaluated for the cause of a hypoglycemic episode. He was underweight (body mass index: 17.3 kg/m2) with sarcopenia, which potentially contributed to his hypoglycemia. Notably, he exhibited progressed proliferative diabetic retinopathy compared to other microvascular complications, leading to further endocrinological investigation. As a result, he was diagnosed with acromegaly showing elevated GH and insulin-like growth factor-1 (IGF-1) with a pituitary tumor. Opting against transsphenoidal surgery (TSS), the patient was treated with a somatostatin analog (SSA), achieving normalized IGF-1 levels with a monthly 120 mg lanreotide injection. In this case, acromegaly could lead to sarcopenia from GH-derived gluconeogenesis in the peripheral organs such as the reduction of muscle leading to reduced glucose reserves. Acromegaly in the elderly may present atypicality. Clinicians should be vigilant for unique manifestations such as advanced diabetic retinopathy, even in elderly patients with hypoglycemia.

Two Cases With Type 1 Diabetes Treated With Insulin Pump Therapy Using a Telemedicine Approach During the COVID-19 Pandemic.

Type 1 diabetes mellitus (T1D) is an autoimmune-related disease resulting in insulin dependency, treated with insulin injection via pen devices or continuous subcutaneous insulin infusion (CSII). Face-to-face instruction for managing insulin injection and dosing and machine-to-device troubleshooting are required early to initiate CSII from insulin injections. Thus, T1D individuals may encounter significant barriers to pen devices or CSII introduction if they live in remote rural areas. In this regard, intermittently scanned continuous glucose monitoring (isCGM) can share visualized glucose profiles via a cloud-platform-based system, offering the potential as an effective tool in telemedicine. Herewith, we report two cases of subjects with T1D living in remote rural areas whose CSII was safely introduced in outpatient settings with the aid of cloud-platform-based isCGM and a video-meeting tool. They showed improved glucose profiles after CSII initiation. Even under the coronavirus disease 2019 (COVID-19) pandemic, the telemedicine system enabled healthcare providers to monitor glucose profiles and confirm device procedures of CSII. We emphasize the usefulness of online instruction with cloud-platform-based isCGM for introducing CSII in cases with barriers to healthcare access, particularly during the COVID-19 pandemic.

Optogenetic stimulation of vagal nerves for enhanced glucose-stimulated insulin secretion and ß cell proliferation.

The enhancement of insulin secretion and of the proliferation of pancreatic ß cells are promising therapeutic options for diabetes. Signals from the vagal nerve regulate both processes, yet the effectiveness of stimulating the nerve is unclear, owing to a lack of techniques for doing it so selectively and prolongedly. Here we report two optogenetic methods for vagal-nerve stimulation that led to enhanced glucose-stimulated insulin secretion and to ß cell proliferation in mice expressing choline acetyltransferase-channelrhodopsin 2. One method involves subdiaphragmatic implantation of an optical fibre for the photostimulation of cholinergic neurons expressing a blue-light-sensitive opsin. The other method, which suppressed streptozotocin-induced hyperglycaemia in the mice, involves the selective activation of vagal fibres by placing blue-light-emitting lanthanide microparticles in the pancreatic ducts of opsin-expressing mice, followed by near-infrared illumination. The two methods show that signals from the vagal nerve, especially from nerve fibres innervating the pancreas, are sufficient to regulate insulin secretion and ß cell proliferation.

Phagocytosis by macrophages promotes pancreatic ß cell mass reduction after parturition in mice.

Elucidating the mechanism(s) modulating appropriate tissue size is a critical biological issue. Pancreatic ß cells increase during pregnancy via cellular proliferation, but how ß cells promptly decrease to the original amount after parturition remains unclear. Herein, we demonstrate the role and mechanism of macrophage accumulation in this process. In the final stage of pregnancy, HTR1D signaling upregulates murine ß cell CXCL10, thereby promoting macrophage accumulation in pancreatic islets via the CXCL10-CXCR3 axis. Blocking this mechanism by administering an HTR1D antagonist or the CXCR3 antibody and depleting islet macrophages inhibited postpartum ß cell mass reduction. ß cells engulfed by macrophages increased in postpartum islets, but Annexin V administration suppressed this engulfment and the postpartum ß cell mass reduction, indicating the accumulated macrophages to phagocytose ß cells. This mechanism contributes to both maintenance of appropriate ß cell mass and glucose homeostasis promptly adapting to reduced systemic insulin demand after parturition.

A highly sensitive strategy for monitoring real-time proliferation of targeted cell types in vivo.

Cell proliferation processes play pivotal roles in timely adaptation to many biological situations. Herein, we establish a highly sensitive and simple strategy by which time-series showing the proliferation of a targeted cell type can be quantitatively monitored in vivo in the same individuals. We generate mice expressing a secreted type of luciferase only in cells producing Cre under the control of the Ki67 promoter. Crossing these with tissue-specific Cre-expressing mice allows us to monitor the proliferation time course of pancreatic ß-cells, which are few in number and weakly proliferative, by measuring plasma luciferase activity. Physiological time courses, during obesity development, pregnancy and juvenile growth, as well as diurnal variation, of ß-cell proliferation, are clearly detected. Moreover, this strategy can be utilized for highly sensitive ex vivo screening for proliferative factors for targeted cells. Thus, these technologies may contribute to advancements in broad areas of biological and medical research.

Node-by-node diagnosis for multiple ipsilateral nodules by segmental adrenal venous sampling in primary aldosteronism.

OBJECTIVES: In patients with primary aldosteronism (PA), multiple adrenocortical nodules may be present on the surgical side. The aim of this study was to clarify the pathological diagnosis and the node-by-node diagnostic capability of segmental adrenal venous sampling (sAVS). DESIGN: Retrospective study. PATIENTS: A total of 162 patients who underwent adrenalectomy following sAVS were studied. MEASUREMENTS: Multiple nodules on the surgical side were extracted while referring to contrast-enhanced computed tomography images. We also performed a detailed histopathological analysis of the resected specimens from patients undergoing sAVS, which included immunohistochemistry for CYP11B2. RESULTS: In 11 (6.8%) patients, two to three nodules were detected on the surgical side. All patients were diagnosed by sAVS with at least one aldosterone-producing adenoma (APA) for localized aldosterone elevation in tributaries. Seven patients showed a lateralization index value of ≥4 after ACTH stimulation. Histopathologically and clinically, two patients had two or three CYP11B2-positive APAs, and the other nine patients both APAs and non-APAs. The positive predictive value of the most suspected APA, that is, the drainer that showed the highest aldosterone level by sAVS, was 11/11 (100%, 95% confidence interval [CI]: 71.5%-100%), while that for the second and third suspected APA was 3/7 (42.9%, 95% CI: 9.9%-81.6%), and they were significantly different (p = .01). Further, the positive predictive value of non-APA was 4/4 (100%, 95% CI: 39.8%-100%). CONCLUSIONS: The sAVS could correctly diagnose the aldosterone production in multiple ipsilateral adrenal nodules.

Insulin-like growth factor-1 levels are associated with high comorbidity of metabolic disorders in obese subjects; a Japanese single-center, retrospective-study.

Insulin like growth factor-1 (IGF-1) plays important roles in metabolic functions, especially in adulthood. Additionally, obese subjects are reportedly predisposed to having low absolute IGF-1 levels. However, the prevalence and clinical characteristics of obese subjects with low IGF-1 levels are unknown. We examined 64 obese subjects with a body mass index (BMI) ≥ 35 kg/m2, with no history of endocrinological disorders, receiving inpatient care. IGF-1 levels were interpreted based on the IGF-1 standard deviation score (SDS) clinically used and standardized by age and sex (low IGF-1 group; ≤ - 2.0 SDS and standard IGF-1 group; - 2.0 < and < + 2.0 SDS). Notably, 26.6% of the subjects had low IGF-1. Body fat mass and percentage, but not BMI, were significantly higher in the low than in the standard IGF-1 group. Furthermore, natural log-transformed high-sensitivity C-reactive protein, and the frequencies of dyslipidemia and hyperuricemia were higher in the low IGF-1 group. Moreover, among the subjects without diabetes, fasting glucose levels were significantly higher in the low IGF-1 group. Stepwise variable selection procedure revealed body fat percentage to be a parameter most strongly associated with low IGF-1. Thus, low IGF-1 levels may be an important marker of adiposity-associated metabolic disorders in obese patients.

A Case of 123I-Metaiodobenzylguanidine Scintigraphy-Negative Pheochromocytoma with a Tumor-Developing Mutation in the RET Gene.

Pheochromocytoma (PCC) is rare catecholamine-producing endocrine tumor that metastasizes in approximately 10% of cases. As a functional imaging of PCC, 123I-metaiodobenzylguanidine (MIBG) scintigraphy was established, and some cases of PCC exhibit negative accumulation on MIBG scintigraphy, indicating a high risk of metastasis. Additionally, germline genetic variants of PCC are evident in approximately 30% of cases, although the genotype-phenotype correlation in PCC, especially the association between genetic mutations and MIBG scintigraphy, remains unclear. A 33-year-old man was admitted to our hospital for further examination for hypertension. He was diagnosed with sporadic PCC, and left adrenalectomy was performed. The adrenal tumor was negative on MIBG scintigraphy. Histology of the tumor revealed a moderately differentiated PCC. Target gene testing revealed a mutation in RET (c.2071G > A). This mutation has been reported to be a tumor-developing gene involved in the pathogenesis of PCC. Moreover, the RET mutation is the only gene mutation reported in a previous study of PCC with negative results on MIBG scintigraphy, except for the SDHB gene mutation, which is a common mutation in metastatic PCC. Correctively, the present RET gene mutation may be associated to MIBG-scintigraphy negative PCC and its pathophysiology. Clinicians should follow such cases more cautiously in clinical practice.

Phenotypic Variability in a Family with Carney Complex Accompanied by a Novel Mutation Involving PRKAR1A.

Carney complex is a rare, autosomal dominant disease accompanied by multiple endocrine neoplastic syndromes. Mutations in the PRKAR1A gene have recently been reported as a cause of Carney complex, but genotype-phenotype correlations vary widely. A 15-year-old Japanese man (Case 1) with short stature visited our hospital with suspected Cushing's syndrome. Biochemical investigations suggested corticotropin-independent Cushing's syndrome. Computed tomography revealed multiple bilateral adrenal tumors, and a two-staged partial adrenalectomy was performed. Pathological findings revealed primary pigmented nodular adrenocortical disease (PPNAD). The patient also exhibited distinctive spotty skin pigmentation. Based on these features, the patient was diagnosed as Carney complex. Cascade screening of family members was performed, and the mother (Case 2) and elder brother (Case 3) were diagnosed as Carney complex. Case 2 showed cardiac myxoma, acromegaly, spotty skin pigmentation, and mammary myxoid fibroadenoma. Case 3 exhibited gigantism, spotty skin pigmentation, and thyroid nodules. Target gene testing in Case 1 and 2 revealed the same novel mutation in PRKAR1A gene (c.503G>T, p.Gly168Val). This mutation was predicted as a pathogenic variant by multiple in silico analyses. Here, we present a family of Carney complex cases with a novel PRKAR1A pathogenic variant exhibiting varied clinical phenotypes within each case. In these cases, some specific phenotypes of Carney complex, such as pigmentary disorders, myxomas, and PPNAD are important as clues for diagnosis and prognostic factors. Clinicians should consider further examination in patients with Carney complex-specific phenotypes.

Roles of FoxM1-driven basal ß-cell proliferation in maintenance of ß-cell mass and glucose tolerance during adulthood.

AIMS/INTRODUCTION: Whether basal ß-cell proliferation during adulthood is involved in maintaining sufficient ß-cell mass, and if so, the molecular mechanism(s) underlying basal ß-cell proliferation remain unclear. FoxM1 is a critical transcription factor which is known to play roles in 'adaptive' ß-cell proliferation, which facilitates rapid increases in ß-cell mass in response to increased insulin demands. Therefore, herein we focused on the roles of ß-cell FoxM1 in 'basal' ß-cell proliferation under normal conditions and in the maintenance of sufficient ß-cell mass as well as glucose homeostasis during adulthood. MATERIALS AND METHODS: FoxM1 deficiency was induced specifically in ß-cells of 8-week-old mice, followed by analyzing its short- (2 weeks) and long- (10 months) term effects on ß-cell proliferation, ß-cell mass, and glucose tolerance. RESULTS: FoxM1 deficiency suppressed ß-cell proliferation at both ages, indicating critical roles of FoxM1 in basal ß-cell proliferation throughout adulthood. While short-term FoxM1 deficiency affected neither ß-cell mass nor glucose tolerance, long-term FoxM1 deficiency suppressed ß-cell mass increases with impaired insulin secretion, thereby worsening glucose tolerance. In contrast, the insulin secretory function was not impaired in islets isolated from mice subjected to long-term ß-cell FoxM1 deficiency. Therefore, ß-cell mass reduction is the primary cause of impaired insulin secretion and deterioration of glucose tolerance due to long-term ß-cell FoxM1 deficiency. CONCLUSIONS: Basal low-level proliferation of ß-cells during adulthood is important for maintaining sufficient ß-cell mass and good glucose tolerance and ß-cell FoxM1 underlies this mechanism. Preserving ß-cell FoxM1 activity may prevent the impairment of glucose tolerance with advancing age.

Characteristics of aldosterone-producing adenomas in patients without plasma renin activity suppression.

Primary aldosteronism (PA) usually accompanies suppressed plasma renin activity (PRA) through a negative feedback mechanism. While some cases of PA with unsuppressed PRA were reported, there have been no studies about the characteristics of PA with unsuppressed PRA; thus, these characteristics were examined herein. Nine patients with unsuppressed PRA and 86 patients with suppressed PRA were examined. All patients underwent segmental adrenal venous sampling (sAVS) and adrenalectomy, and were pathologically confirmed to have cytochrome P450 11B2 (CYP11B2)-positive aldosterone-producing adenoma according to international histopathology consensus criteria. Unsuppressed and suppressed PRA were defined as PRA levels of > 1.0 and ≤ 1.0 ng/mL/hr, respectively, in multiple blood samples obtained in the resting position. The unsuppressed PRA group had higher morning cortisol levels (12.6 [8.5, 13.5] vs. 8.5 [7.1, 11.0] µg/dL, P = 0.03) and higher cortisol levels after a 1 mg dexamethasone suppression test (DST) (2.2 [1.6, 2.5] vs. 1.3 [1.0, 1.9] µ g/dL, P = 0.004) than the suppressed PRA group. The unsuppressed PRA group also showed higher aldosterone levels on the non-surgical side during sAVS (P = 0.02 before adrenocorticotropic hormone (ACTH) stimulation, P = 0.002 after ACTH stimulation), a higher intensity of CYP17 expression in the resected adrenal gland (P = 0.02), and a lower clinical complete success rate 1 year after surgery (P = 0.04) compared with those in the suppressed PRA group. These findings suggest that PA should not be ruled out by unsuppressed PRA among patients with hypertension, particularly when their cortisol levels remain unsuppressed in the 1 mg DST. Meanwhile, it should be acknowledged that patients with unsuppressed PRA have higher aldosterone levels on the non-surgical side, and a lower likelihood of postoperative complete clinical success is to be expected.

Precise Mapping of Intra-Adrenal Aldosterone Activities Provides a Novel Surgical Strategy for Primary Aldosteronism.

Segmental selective adrenal venous sampling (sAVS) elucidates an intraadrenal aldosterone activity map (IAMap), which allows us to design a novel surgical treatment strategy for patients with primary aldosteronism. We evaluated the usefulness of sAVS by analyzing 278 patients with whom we had prospectively used IAMap using the criteria of sAVS for surgical indication between 2009 and 2015. We evaluated its diagnostic accuracy using pathological and postsurgical biochemical and clinical outcomes. One hundred twenty and 158 patients were diagnosed with unilateral and bilateral disease, respectively, through sAVS. The concordance of lateralization diagnosis with computed tomography imaging was 66.6%. Among the unilateral patients, we performed partial adrenalectomy in 68 patients whose IAMap showed focal aldosterone hypersecretion from computed tomography-detectable tumor in the affected adrenal gland. All of them achieved complete biochemical success 1 year after surgery. Furthermore, 25 of 158 bilateral disease patients underwent surgical resection because they were preoperatively diagnosed as bilateral aldosterone-producing adenomas by IAMap. These cases showed complete or partial biochemical success (28.0% and 72.0%, respectively); 36.0% showed complete clinical success. Pathological studies demonstrated that all 145 resected specimens possessed aldosterone-producing adenoma or multiple nodules (132 and 13 cases, respectively), and none showed diffuse hyperplasia. IAMap accurately diagnosed both bilateral and unilateral aldosterone-producing adenomas and diffuse hyperplasia before surgery. sAVS allows a novel surgical strategy for selected PA patients with favorable outcomes.

A SNARE geranylgeranyltransferase essential for the organization of the Golgi apparatus.

Protein prenylation is essential for many cellular processes including signal transduction, cytoskeletal reorganization, and membrane trafficking. Here, we identify a novel type of protein prenyltransferase, which we named geranylgeranyltransferase type-III (GGTase-III). GGTase-III consists of prenyltransferase alpha subunit repeat containing 1 (PTAR1) and the ß subunit of RabGGTase. Using a biotinylated geranylgeranyl analogue, we identified the Golgi SNARE protein Ykt6 as a substrate of GGTase-III. GGTase-III transfers a geranylgeranyl group to mono-farnesylated Ykt6, generating doubly prenylated Ykt6. The crystal structure of GGTase-III in complex with Ykt6 provides structural basis for Ykt6 double prenylation. In GGTase-III-deficient cells, Ykt6 remained in a singly prenylated form, and the Golgi SNARE complex assembly was severely impaired. Consequently, the Golgi apparatus was structurally disorganized, and intra-Golgi protein trafficking was delayed. Our findings reveal a fourth type of protein prenyltransferase that generates geranylgeranyl-farnesyl Ykt6. Double prenylation of Ykt6 is essential for the structural and functional organization of the Golgi apparatus.

A Patient with Nivolumab-related Fulminant Type 1 Diabetes Mellitus whose Serum C-peptide Level Was Preserved at the Initial Detection of Hyperglycemia.

A 77-year-old-man with renal cell carcinoma who was undergoing nivolumab treatment visited our department due to hyperglycemia; his plasma glucose level was 379 mg/dL. Although his serum C-peptide immunoreactivity (CPR) level was preserved (5.92 ng/mL), we suspected an onset of fulminant type 1 diabetes mellitus (FT1DM) and immediately started insulin therapy. His CPR levels gradually decreased and were depleted within 1 week. We later discovered that the patient's casual CPR level had been abnormally high (11.78 ng/mL) 2 weeks before his admission. Hence, the possibility of FT1DM in hyperglycemic patients undergoing nivolumab treatment should not be excluded, even with a preserved CPR level.

Liver Abscess and Portal Vein Thrombosis Due to Ileal Diverticulitis Mediated by Barium Fluoroscopy.

We report a case of liver abscess and portal vein thrombosis, which occurred due to diverticulitis at the terminal ileum in a 59-year-old man. The patient underwent a barium fluoroscopic examination 1 month before presenting to our hospital. He also showed liver dysfunction due to thrombosis at the superior mesenteric and portal veins. His inflammation gradually subsided after the initiation of treatment, but the recovery was not sufficient. Thus, surgery was performed. The patient condition improved after surgery and he was discharged. Barium examinations are relatively safe, but can sometimes cause severe adverse effects in patients with certain risk factors, and an appropriate diagnosis and treatment are necessary when symptoms appear.