Cardiovascular Outcomes of KCNJ5 mutated Aldosterone-Producing Adenoma: A Systematic Review

BACKGROUND

While clinical features of KCNJ5-mutated aldosterone-producing adenoma (APA) have been reported, evidence of its clinical outcomes is lacking. We aimed to synthesize available literature about the associations between KCNJ5 mutation with cardiovascular and metabolic outcomes among patients with APA.

METHODS

In this systematic review of observational studies, MEDLINE and EMBASE were searched through August 2022. Two independent authors screened the search results and extracted data from eligible observational studies investigating cardiovascular or metabolic outcomes between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs. Risk of Bias In Non-randomized Studies of Interventions was used to assess the quality of the included studies.

RESULTS

A total of 573 titles/abstracts were screened and after the expert opinion of the literature, 20 were read the full text, of which 12 studies were included. Across three studies comparing the baseline or change in the cardiac function between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs, all studies reported the association between impaired cardiac functions and KCNJ5 mutation status. Among six studies evaluating the cure of hypertension after surgery, all studies showed that KCNJ5 mutation was significantly associated with the cure of hypertension. In quality assessment, seven studies were at serious risk of bias, while the remaining studies were at moderate risk of bias.

CONCLUSIONS

This systematic review provided evidence of the significant association between KCNJ5 mutation and unfavorable cardiovascular outcomes in patients with primary aldosteronism. Further research is needed to improve the quality of evidence on this topic and elucidate the underlying mechanisms of the potential burden of KCNJ5 mutation.

Diabetes treatment by conversion of gut epithelial cells to insulin-producing cells

Insulin-deficient (type 1) diabetes is treated by providing insulin to maintain euglycemia. The current standard of care is a quasi-closed loop integrating automated insulin delivery with a continuous glucose monitoring sensor. Cell replacement technologies are advancing as an alternative treatment and have been tested as surrogates to cadaveric islets in transplants. In addition, immunomodulatory treatments to delay the onset of type 1 diabetes in high-risk (stage 2) individuals have gained regulatory approval. We have pioneered a cell conversion approach to restore insulin production through pharmacological conversion of intestinal epithelial cells into insulin-producing cells. We have advanced this approach along a translational trajectory through the discovery of small molecule forkhead box protein O1 inhibitors. When administered to different rodent models of insulin-deficient diabetes, these inhibitors have resulted in robust glucose-lowering responses and generation of insulin-producing cells in the gut epithelium. We review past work and delineate a path to human clinical trials.

Sex differences in symptom presentation and their impact on diagnostic accuracy in Werner syndrome

AIM

Whether sex differences exist in hereditary progeroid syndromes remains unclear. In this study, we investigated sex differences in patients with Werner syndrome (WS), a model of human aging, using patient data at the time of diagnosis.

METHODS

The presence of six cardinal signs in the diagnostic criteria was retrospectively evaluated.

RESULTS

We found that the percentage of patients with all cardinal signs was higher in males than in females (54.2% vs. 21.2%). By the age of 40 years, 57.1% of male patients with WS presented with all the cardinal signs, whereas none of the female patients developed all of them. In particular, the frequency of having a high-pitched, hoarse voice, a characteristic of WS, was lower in female patients. The positive and negative predictive values for clinical diagnosis were 100% for males and females, indicating the helpfulness of diagnostic criteria regardless of sex. More female patients than male (86.7% vs. 64%) required genetic testing for their diagnosis because their clinical symptoms were insufficient, suggesting the importance of genetic testing for females even if they do not show typical symptoms of WS. Finally, the frequency of abnormal voice was lower in patients with WS harboring the c.3139-1G > C homozygous mutation.

CONCLUSION

These results indicate, for the first time, that there are sex differences in the phenotypes of hereditary progeroid syndromes. The analysis of this mechanism in this human model of aging may lead to the elucidation of sex differences in the various symptoms of normal human aging. Geriatr Gerontol Int 2024; 24: 161-167.

Identifying primary aldosteronism patients who require adrenal venous sampling: a multi-center study

Adrenal venous sampling (AVS) is crucial for subtyping primary aldosteronism (PA) to explore the possibility of curing hypertension. Because AVS availability is limited, efforts have been made to develop strategies to bypass it. However, it has so far proven unsuccessful in applying clinical practice, partly due to heterogeneity and missing values of the cohorts. For this purpose, we retrospectively assessed 210 PA cases from three institutions where segment-selective AVS, which is more accurate and sensitive for detecting PA cases with surgical indications, was available. A machine learning-based classification model featuring a new cross-center domain adaptation capability was developed. The model identified 102 patients with PA who benefited from surgery in the present cohort. A new data imputation technique was used to address cross-center heterogeneity, making a common prediction model applicable across multiple cohorts. Logistic regression demonstrated higher accuracy than Random Forest and Deep Learning [(0.89, 0.86) vs. (0.84, 0.84), (0.82, 0.84) for surgical or medical indications in terms of f-score]. A derived integrated flowchart revealed that 35.2% of PA cases required AVS with 94.1% accuracy. The present model enabled us to reduce the burden of AVS on patients who would benefit the most.

Senescence-associated inflammation and inhibition of adipogenesis in subcutaneous fat in Werner syndrome

Werner syndrome (WS) is a hereditary premature aging disorder characterized by visceral fat accumulation and subcutaneous lipoatrophy, resulting in severe insulin resistance. However, its underlying mechanism remains unclear. In this study, we show that senescence-associated inflammation and suppressed adipogenesis play a role in subcutaneous adipose tissue reduction and dysfunction in WS. Clinical data from four Japanese patients with WS revealed significant associations between the decrease of areas of subcutaneous fat and increased insulin resistance measured by the glucose clamp. Adipose-derived stem cells from the stromal vascular fraction derived from WS subcutaneous adipose tissues (WSVF) showed early replicative senescence and a significant increase in the expression of senescence-associated secretory phenotype (SASP) markers. Additionally, adipogenesis and insulin signaling were suppressed in WSVF, and the expression of adipogenesis suppressor genes and SASP-related genes was increased. Rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR), alleviated premature cellular senescence, rescued the decrease in insulin signaling, and extended the lifespan of WS model of C. elegans. To the best of our knowledge, this study is the first to reveal the critical role of cellular senescence in subcutaneous lipoatrophy and severe insulin resistance in WS, highlighting the therapeutic potential of rapamycin for this disease.

Unraveling the mysteries of hepatic insulin signaling: deconvoluting the nuclear targets of insulin

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.

Feasibility of single-port laparoscopic partial adrenalectomy with selective adrenal venous sampling and high-resolution ultrasound for unilateral aldosterone-producing adenomas

BACKGROUND

The surgical and endocrinological outcomes of single-port laparoscopic partial adrenalectomy for patients with aldosterone-producing adenomas are unknown. Precise diagnosis of intra-adrenal aldosterone activity and a precise surgical procedure may improve outcomes. In this study, we aimed to determine the surgical and endocrinological outcomes of single-port laparoscopic partial adrenalectomy with preoperative segmental selective adrenal venous sampling and intraoperative high-resolution laparoscopic ultrasound in patients with unilateral aldosterone-producing adenomas. We identified 53 patients with partial adrenalectomy and 29 patients with laparoscopic total adrenalectomy. Single-port surgery was performed for 37 and 19 patients, respectively.

METHODS

A single-center, retrospective cohort study. All patients with unilateral aldosterone-producing adenomas diagnosed by selective adrenal venous sampling and treated surgically between January 2012 and February 2015 were included. Follow-up with biochemical and clinical assessments was set at 1 year after surgery for short-term outcomes and was performed every 3 months after surgery.

RESULTS

We identified 53 patients with partial adrenalectomy and 29 patients with laparoscopic total adrenalectomy. Single-port surgery was performed for 37 and 19 patients, respectively. Single-port surgery was associated with shorter operative and laparoscopic times (odds ratio, 0.14; 95% confidence interval, 0.039-0.49; P = .002 and odds ratio, 0.13; 95% confidence interval, 0.032-0.57; P = .006, respectively). All single-port and multi-port partial adrenalectomy cases showed complete short-term (median 1 year) biochemical success, and 92.9% (26 of 28 patients) who underwent single-port partial adrenalectomy and 100% (13 of 13 patients) who underwent multi-port partial adrenalectomy showed complete long-term (median 5.5 years) biochemical success. No complications were observed with single-port adrenalectomy.

CONCLUSION

Single-port partial adrenalectomy is feasible after selective adrenal venous sampling for unilateral aldosterone-producing adenomas, with shorter operative and laparoscopic times and a high rate of complete biochemical success.

Calorie Restriction activates a gastric Notch-FOXO1 pathway to expand Ghrelin cells

Calorie restriction increases lifespan. While some tissue-specific protective effects of calorie restriction have been described, the impact of calorie restriction on the gastrointestinal tract remains unclear. We found increased abundance of chromogranin A+, including orexigenic ghrelin+, endocrine cells in the stomach of calorie-restricted mice. This effect coincided with increased Notch target Hes1 and Notch ligand Jag1 and was reversed when Notch signaling was blocked using the γ-secretase inhibitor DAPT. Using primary cultures and genetically-modified reporter mice, we determined that increased endocrine cell abundance was due to altered stem and progenitor proliferation. Different from the intestine, calorie restriction decreased gastric Lgr5+ stem cells, while increasing a FOXO1/Neurog3+ subpopulation of endocrine progenitors in a Notch-dependent manner. Further, calorie restriction triggered nuclear localization of FOXO1, which was sufficient to promote endocrine cell differentiation. Taken together, the data indicate that calorie restriction promotes gastric endocrine cell differentiation triggered by active Notch signaling and regulated by FOXO1.

Cyb5r3-based mechanism and reversal of secondary failure to sulfonylurea in diabetes

Sulfonylureas (SUs) are effective and affordable antidiabetic drugs. However, chronic use leads to secondary failure, limiting their utilization. Here, we identify cytochrome b5 reductase 3 (Cyb5r3) down-regulation as a mechanism of secondary SU failure and successfully reverse it. Chronic exposure to SU lowered Cyb5r3 abundance and reduced islet glucose utilization in mice in vivo and in ex vivo murine islets. Cyb5r3 β cell-specific knockout mice phenocopied SU failure. Cyb5r3 engaged in a glucose-dependent interaction that stabilizes glucokinase (Gck) to maintain glucose utilization. Hence, Gck activators can circumvent Cyb5r3-dependent SU failure. A Cyb5r3 activator rescued secondary SU failure in mice in vivo and restored insulin secretion in ex vivo human islets. We conclude that Cyb5r3 is a key factor in the secondary failure to SU and a potential target for its prevention, which might rehabilitate SU use in diabetes.

Reflections on the state of diabetes research and prospects for treatment

Research on the etiology and treatment of diabetes has made substantial progress. As a result, several new classes of anti-diabetic drugs have been introduced in clinical practice. Nonetheless, the number of patients achieving glycemic control targets has not increased for the past 20 years. Two areas of unmet medical need are the restoration of insulin sensitivity and the reversal of pancreatic beta cell failure. In this review, we integrate research advances in transcriptional regulation of insulin action and pathophysiology of beta cell dedifferentiation with their potential impact on prospects of a durable "cure" for patients suffering from type 2 diabetes.

Pharmacological conversion of gut epithelial cells into insulin-producing cells lowers glycemia in diabetic animals

As a highly regenerative organ, the intestine is a promising source for cellular reprogramming for replacing lost pancreatic β cells in diabetes. Gut enterochromaffin cells can be converted to insulin-producing cells by forkhead box O1 (FoxO1) ablation, but their numbers are limited. In this study, we report that insulin-immunoreactive cells with Paneth/goblet cell features are present in human fetal intestine. Accordingly, lineage-tracing experiments show that, upon genetic or pharmacologic FoxO1 ablation, the Paneth/goblet lineage can also undergo conversion to the insulin lineage. We designed a screening platform in gut organoids to accurately quantitate β-like cell reprogramming and fine-tune a combination treatment to increase the efficiency of the conversion process in mice and human adult intestinal organoids. We identified a triple blockade of FOXO1, Notch, and TGF-β that, when tested in insulin-deficient streptozotocin (STZ) or NOD diabetic animals, resulted in near normalization of glucose levels, associated with the generation of intestinal insulin-producing cells. The findings illustrate a therapeutic approach for replacing insulin treatment in diabetes.

Chemical induction of gut β-like-cells by combined FoxO1/Notch inhibition as a glucose-lowering treatment for diabetes

OBJECTIVE

Lifelong insulin replacement remains the mainstay of type 1 diabetes treatment. Genetic FoxO1 ablation promotes enteroendocrine cell (EECs) conversion into glucose-responsive β-like cells. Here, we tested whether chemical FoxO1 inhibitors can generate β-like gut cells.

METHODS

We used Ngn3-or Villin-driven FoxO1 ablation to capture the distinctive developmental effects of FoxO1 on EEC pool. We combined FoxO1 ablation with Notch inhibition to enhance the expansion of EEC pool. We tested the ability of an orally available small molecule of FoxO1 inhibitor, Cpd10, to phenocopy genetic ablation of FoxO1. We evaluated the therapeutic impact of genetic ablation or chemical inhibition of FoxO1 on insulin-deficient diabetes in Ins2^Akita/+ mice.

RESULTS

Pan-intestinal epithelial FoxO1 ablation expanded the EEC pool, induced β-like cells, and improved glucose tolerance in Ins2^Akita/+ mice. This genetic effect was phenocopied by Cpd10. Cpd10 induced β-like cells that released insulin in response to glucose in gut organoids, and this effect was enhanced by the Notch inhibitor, DBZ. In Ins2^Akita/+ mice, a five-day course of either Cpd10 or DBZ induced intestinal insulin-immunoreactive β-like cells, lowered glycemia, and increased plasma insulin levels without apparent adverse effects.

CONCLUSION

These results provide proof of principle of gut cell conversion into β-like cells by a small molecule FoxO1 inhibitor, paving the way for clinical applications.

FOXO1 Is Present in Stomach Epithelium and Determines Gastric Cell Distribution

BACKGROUND AND AIMS

Stomach cells can be converted to insulin-producing cells by Neurog3, MafA, and Pdxl over-expression. Enteroendocrine cells can be similarly made to produce insulin by the deletion of FOXO1. Characteristics and functional properties of FOXO1-expressing stomach cells are not known.

METHODS

Using mice bearing a FOXO1-GFP knock-in allele and primary cell cultures, we examined the identity of FOXO1-expressing stomach cells and analyzed their features through loss-of-function studies with red-to-green fluorescent reporters.

RESULTS

FOXO1 localizes to a subset of Neurog3 and parietal cells. FOXO1 deletion ex vivo or in vivo using Neurog3-cre or Atp4b-cre increased numbers of parietal cells, generated insulin- and C-peptide-immunoreactive cells, and raised Neurog3 messenger RNA. Gene expression and ChIP- seq experiments identified the cell cycle regulator cyclin E1 (CCNE1) as a FOXO1 target.

CONCLUSION

FOXO1 is expressed in a subset of stomach cells. Its ablation increases parietal cells and yields insulin-immunoreactive cells, consistent with a role in lineage determination.

Hepatic FoxOs link insulin signaling with plasma lipoprotein metabolism through an apolipoprotein M/sphingosine-1-phosphate pathway

Multiple beneficial cardiovascular effects of HDL depend on sphingosine-1-phosphate (S1P). S1P associates with HDL by binding to apolipoprotein M (ApoM). Insulin resistance is a major driver of dyslipidemia and cardiovascular risk. However, the mechanisms linking alterations in insulin signaling with plasma lipoprotein metabolism are incompletely understood. The insulin-repressible FoxO transcription factors mediate key effects of hepatic insulin action on glucose and lipoprotein metabolism. This work tested whether hepatic insulin signaling regulates HDL-S1P and aimed to identify the underlying molecular mechanisms. We report that insulin-resistant, nondiabetic individuals had decreased HDL-S1P levels, but no change in total plasma S1P. This also occurred in insulin-resistant db/db mice, which had low ApoM and a specific reduction of S1P in the HDL fraction, with no change in total plasma S1P levels. Using mice lacking hepatic FoxOs (L-FoxO1,3,4), we found that hepatic FoxOs were required for ApoM expression. Total plasma S1P levels were similar to those in controls, but S1P was nearly absent from HDL and was instead increased in the lipoprotein-depleted plasma fraction. This phenotype was restored to normal by rescuing ApoM in L-FoxO1,3,4 mice. Our findings show that insulin resistance in humans and mice is associated with decreased HDL-associated S1P. Our study shows that hepatic FoxO transcription factors are regulators of the ApoM/S1P pathway.

An integrative transcriptional logic model of hepatic insulin resistance

Abnormalities of lipid/lipoprotein and glucose metabolism are hallmarks of hepatic insulin resistance in type 2 diabetes. The former antedate the latter, but the latter become progressively refractory to treatment and contribute to therapeutic failures. It's unclear whether the two processes share a common pathogenesis and what underlies their progressive nature. In this study, we investigated the hypothesis that genes in the lipid/lipoprotein pathway and those in the glucose metabolic pathway are governed by different transcriptional regulatory logics that affect their response to physiologic (fasting/refeeding) as well as pathophysiologic cues (insulin resistance and hyperglycemia). To this end, we obtained genomic and transcriptomic maps of the key insulin-regulated transcription factor, FoxO1, and integrated them with those of CREB, PPAR-α, and glucocorticoid receptor. We found that glucose metabolic genes are primarily regulated by promoter and intergenic enhancers in a fasting-dependent manner, while lipid genes are regulated through fasting-dependent intron enhancers and fasting-independent enhancerless introns. Glucose genes also showed a remarkable transcriptional resiliency (i.e., the ability to compensate following constitutive FoxO1 ablation through an enrichment of active marks at shared PPAR-α/FoxO1 regulatory elements). Unexpectedly, insulin resistance and hyperglycemia were associated with a "spreading" of FoxO1 binding to enhancers and the emergence of unique target sites. We surmise that this unusual pattern correlates with the progressively intractable nature of hepatic insulin resistance. This transcriptional logic provides an integrated model to interpret the combined lipid and glucose abnormalities of type 2 diabetes.

Low dose red yeast rice with monacolin K lowers LDL cholesterol and blood pressure in Japanese with mild dyslipidemia: A multicenter, randomized trial

BACKGROUND AND OBJECTIVES

Red yeast rice contains monacolin K, an inhibitor of cholesterol synthesis, and gamma-aminobutyric acid, a neurotransmitter. The daily dose of red yeast rice and monacolin K in previous studies was relatively high; therefore, there were safety concerns. We aimed to examine the effects of low daily dose red yeast rice on arteriosclerosis in patients with mild dyslipidemia.

METHODS AND STUDY DESIGN

Eighteen patients without known cardiovascular disease and unsatisfactory low-density lipoprotein cholesterol (3.96±0.19 mmol/L) controlled only by diet therapy were randomly allocated to receive low dose red yeast rice (200 mg/day) containing 2 mg monacolin K or diet therapy alone for 8 weeks. The primary outcome was the absolute change in low-density lipoprotein cholesterol. Secondary outcomes included total cholesterol, apolipoprotein B, and blood pressure.

RESULTS

Low-density lipoprotein cholesterol decreased significantly in the red yeast rice group than in the diet therapy group (median [interquartile range]: control -0.20 [-0.62, 1.19] mmol/L vs. red yeast rice -0.96 [-1.05, -0.34] mmol/L, p=0.030). The red yeast rice group also exhibited significant decreases in total cholesterol, apolipoprotein B, and blood pressure. No severe treatment-related adverse effects on muscles, liver, or renal function were observed.

CONCLUSIONS

We found that patients in the red yeast rice group exhibited significant reductions in lowdensity lipoprotein cholesterol, total cholesterol, apolipoprotein B, and blood pressure without any recognised adverse effect. This suggests that low daily dose red yeast rice could reduce cardiovascular risk in patients with dyslipidemia.

Favorable Effects of 24-Week Whole-Body Vibration on Glycemic Control and Comprehensive Diabetes Therapy in Elderly Patients with Type 2 Diabetes

BACKGROUND

Elderly patients with type 2 diabetes (T2DM) are vulnerable to treatment-inducible hypoglycemia, falls, and depressive symptoms. Although it is challenging for elderly patients to adhere to regular exercise, its positive effect on functional ability, glycemic control, and mental wellness offers comprehensive diabetes treatment. In the present study, we aimed to investigate a novel exercise approach for the elderly, focusing on whole-body vibration (WBV).

METHODS

This retrospective cohort study was conducted in a primary-care setting at a medical fitness center affiliated with the incorporated medical institution of THY (TOTAL HEALTH YARD). Fourteen (WBV group) and 12 (control group) elderly patients with T2DM undergoing and not undergoing our WBV program, respectively, for > 6 months were analyzed. Primary endpoints were the functional ability changes, evaluated by Timed Up and Go (TUG), Sit-to-Stand test (SST), gait length, and grip test. Secondary endpoints were global glycemic control and questionnaires, namely the Diabetes Treatment Satisfaction Questionnaire (DTSQ) and Geriatric Depression Scale (GDS). All records of exercise adherence and any adverse events were followed.

RESULTS

Significant improvements in TUG and SST were found only in the WBV group [TUG: 7.1 ± 0.9, 7.1 ± 0.8 to 7.0 ± 1.0, 6.6 ± 0.9 (s), P = 0.63, 0.01; SST: 10.4 ± 1.9, 11.3 ± 2.4 to 9.7 ± 2.3, 9.5 ± 2.1 (s), P = 0.62, P < 0.01, control vs. WBV group, respectively]. The WBV group demonstrated significant improvement of hemoglobin A1C levels (7.2 ± 0.8 to 6.9 ± 0.5, P < 0.01) and DTSQ and GDS scores, while the control group did not. There were no hypoglycemic events during the study. The WBV program adherence was 93.3 ± 8.0%.

CONCLUSION

We demonstrated the favorable effect of WBV training on balance, diabetes treatment, and mood. Therefore, WBV training can be proposed as comprehensive therapy in a safe manner and potentially has a positive effect on health-related quality of life in elderly patients with T2DM.

Effects of ipragliflozin versus metformin in combination with sitagliptin on bone and muscle in Japanese patients with type 2 diabetes mellitus: Subanalysis of a prospective, randomized, controlled study (PRIME-V study)

AIMS/INTRODUCTION

Recent randomized clinical trials have suggested that sodium-glucose cotransporter 2 inhibitors might reduce cardiovascular events and heart failure, and have renal protective effects. Despite these remarkable benefits, the effects of sodium-glucose cotransporter 2 inhibitors on bone and muscle are unclear.

MATERIALS AND METHODS

A subanalysis of a randomized controlled study was carried out to evaluate the effects of the sodium-glucose cotransporter 2 inhibitor, ipragliflozin, versus metformin on bone and muscle in Japanese patients with type 2 diabetes mellitus (baseline body mass index ≥22 kg/m2 and hemoglobin A1c 7-10%) who were already receiving sitagliptin. These patients were randomly administered ipragliflozin 50 mg or metformin 1,000-1,500 mg daily. The effects of these medications on the bone formation marker, bone alkali phosphatase; the bone resorption marker, tartrate-resistant acid phosphatase 5b (TRACP-5b); handgrip strength; abdominal cross-sectional muscle area; and bone density of the fourth lumbar vertebra were evaluated.

RESULTS

After 24 weeks of treatment, the changes in bone density of the fourth lumbar vertebra, handgrip strength and abdominal cross-sectional muscle area were not significantly different between the two groups. However, TRACP-5b levels increased in patients treated with ipragliflozin compared with patients treated with metformin (median 11.94 vs -10.30%, P < 0.0001), showing that ipragliflozin can promote bone resorption.

CONCLUSIONS

There were no adverse effects on bone or muscle when sitagliptin was used in combination with either ipragliflozin or metformin. However, ipragliflozin combination increased the levels of TRACP-5b. A long-term study is required to further understand the effects of this TRACP-5b increase caused by ipragliflozin.

Cortisol Co-Secretion and Clinical Usefulness of ACTH Stimulation Test in Primary Aldosteronism: A Systematic Review and Biases in Epidemiological Studies

The hypothalamus-pituitary-adrenal (HPA) axis plays an important role in primary aldosteronism. Aldosterone biosynthesis is regulated not only by angiotensin II in the renin-angiotensin-aldosterone system, but also by adrenocorticotropic hormone (ACTH), one of the key components of the HPA axis. Although previous studies have reported cortisol cosecretion in primary aldosteronism, particularly aldosterone-producing adenoma (APA), the clinical relevance of such aldosterone and cortisol cosecretion from APA and hypertension or other metabolic disorders has not been fully established. Several somatic mutations including KCNJ5 and CACNA1D are known to induce autonomous production of aldosterone in APA, and the aldosterone responsiveness to ACTH may vary according to each mutation. The ACTH stimulation test has been reported to be a useful tool to distinguish the subtypes of primary aldosteronism (e.g., unilateral vs bilateral) in some studies, but it has not been commonly applied in clinical practice due to limited evidence. Given the recent advancement of imaging, omics research, and computational approach, it is important to summarize the most updated evidence to disentangle the potential impact of cortisol excess in primary aldosteronism and whether the ACTH stimulation test needs to be considered during the diagnostic process of primary aldosteronism. In this article, we conducted a systematic review of epidemiological studies about (i) cortisol cosecretion in primary aldosteronism and (ii) the ACTH stimulation test for the diagnosis of primary aldosteronism (including subtype diagnosis). Then, we discussed potential biases (e.g., confounding bias, overadjustment, information bias, selection bias, and sampling bias) in the previous studies and introduced some advanced epidemiological/statistical methods to minimize these limitations. A better understanding of biases and epidemiological perspective on this topic would allow us to produce further robust evidence and balanced discussion about the causal mechanisms involving the HPA axis and clinical usefulness of the ACTH stimulation test among patients with primary aldosteronism.

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.

SUN-646 A Novel Population of FOXO1-Expressing Cells in the Stomach Controls Cell Plasticity by Regulating the Cyclin CCNE1

A promising new therapy for type 1 diabetes is the reprogramming of gut enteroendocrine cells into cells that produce insulin. The mechanism by which gut epithelial cells are converted into cells that make insulin remains unknown. We have previously found that elimination of Foxo1 in neurogenin3 (Ngn3)-expressing cells of the intestine generates glucose-sensing, insulin-producing cells that are capable of reversing streptozotocin-induced diabetes. Others have reported that stomach cells have a similar property when made to express β-cell factors Ngn3, Pdx1, and MafA. Using mice bearing a Foxo1-GFP knock-in allele, we traced Foxo1-expressing cells in the gut to subpopulations of Ngn3+, as well as acid-secreting parietal stomach cells. To study these cells, we established a 2D co-culture method in which primary stomach cells are isolated from mice and cultured with embryonic fibroblasts. Deletion of Foxo1 in this system generated cells immunoreactive for insulin and C-peptide. Interestingly, Foxo1 ablation also altered the abundance of other gastric cell populations, including more parietal cells and decreased expression of stem cell marker, Lgr5. Tissue-specific elimination of Foxo1 in vivo in either Ngn3+ or parietal cells also resulted in the appearance of insulin+ cells, increased parietal cells, and reduced Lgr5 mRNA. To determine how Foxo1 regulated these changes, we used cells isolated from reporter mice that change from red to green after genetic recombination to collect Foxo1-deleted primary stomach cells using FACS. While the mRNA levels of many known Foxo1 targets did not change, cyclin E1 (CCNE1), which regulates G1 to S-phase progression of the cell cycle, was significantly decreased. Conversely, primary stomach cells overexpressing Foxo1 had increased levels of CCNE1. Finally, using ChIP-seq, we found that Foxo1 binds directly to the CCNE promoter in a nutrient-dependent manner. In summary, we show that Foxo1 is expressed in a subpopulation of stomach parietal cells and that it regulates their function through the cell cycle regulator, CCNE1.

Cyb5r3 links FoxO1-dependent mitochondrial dysfunction with β-cell failure

OBJECTIVE

Diabetes is characterized by pancreatic β-cell dedifferentiation. Dedifferentiating β cells inappropriately metabolize lipids over carbohydrates and exhibit impaired mitochondrial oxidative phosphorylation. However, the mechanism linking the β-cell's response to an adverse metabolic environment with impaired mitochondrial function remains unclear.

METHODS

Here we report that the oxidoreductase cytochrome b5 reductase 3 (Cyb5r3) links FoxO1 signaling to β-cell stimulus/secretion coupling by regulating mitochondrial function, reactive oxygen species generation, and nicotinamide actin dysfunction (NAD)/reduced nicotinamide actin dysfunction (NADH) ratios.

RESULTS

The expression of Cyb5r3 is decreased in FoxO1-deficient β cells. Mice with β-cell-specific deletion of Cyb5r3 have impaired insulin secretion, resulting in glucose intolerance and diet-induced hyperglycemia. Cyb5r3-deficient β cells have a blunted respiratory response to glucose and display extensive mitochondrial and secretory granule abnormalities, consistent with altered differentiation. Moreover, FoxO1 is unable to maintain expression of key differentiation markers in Cyb5r3-deficient β cells, suggesting that Cyb5r3 is required for FoxO1-dependent lineage stability.

CONCLUSIONS

The findings highlight a pathway linking FoxO1 to mitochondrial dysfunction that can mediate β-cell failure.

Comparing the effects of ipragliflozin versus metformin on visceral fat reduction and metabolic dysfunction in Japanese patients with type 2 diabetes treated with sitagliptin: A prospective, multicentre, open-label, blinded-endpoint, randomized controlled study (PRIME-V study)

A prospective, multicentre, open-label, blinded-endpoint, randomized controlled study was conducted to evaluate the efficacy of treatment with ipragliflozin (sodium-dependent glucose transporter-2 inhibitor) versus metformin for visceral fat reduction and glycaemic control among Japanese patients with type 2 diabetes treated with sitagliptin, HbA1c levels of 7%-10%, and body mass index (BMI) ≥ 22 kg/m² . Patients were randomly assigned (1:1) to receive ipragliflozin 50 mg or metformin 1000-1500 mg daily. The primary outcome was change in visceral fat area as measured by computed tomography after 24 weeks of therapy. The secondary outcomes were effects on glucose metabolism and lipid metabolism. Mean percentage reduction in visceral fat area was significantly greater in the ipragliflozin group than in the metformin group (-12.06% vs. -3.65%, P = 0.040). Ipragliflozin also significantly reduced BMI, subcutaneous fat area, waist circumference, fasting insulin, and homeostatic model assessment (HOMA)-resistance, and increased HDL-cholesterol levels. Metformin significantly reduced HbA1c and LDL-cholesterol levels and increased HOMA-beta. There were no severe adverse events. The use of ipragliflozin or metformin in combination with dipeptidyl peptidase-4 inhibitors, widely used in Japan, may have beneficial effects in ameliorating multiple cardiovascular risk factors.

Identification of Insulin-Responsive Transcription Factors That Regulate Glucose Production by Hepatocytes

Hepatocyte glucose production is a complex process that integrates cell-autonomous mechanisms with cellular signaling, enzyme activity modulation, and gene transcription. Transcriptional mechanisms controlling glucose production are redundant and involve nuclear hormone receptors and unliganded transcription factors (TFs). Our knowledge of this circuitry is incomplete. Here we used DNA affinity purification followed by mass spectrometry to probe the network of hormone-regulated TFs by using phosphoenolpyruvate carboxykinase (Pck1) and glucose-6-phosphatase (G6pc) in liver and primary hepatocytes as model systems. The repertoire of insulin-regulated TFs is unexpectedly broad and diverse. Whereas in liver the two test promoters are regulated by largely overlapping sets of TFs, in primary hepatocytes Pck1 and G6pc regulation diverges. Insulin treatment preferentially results in increased occupancy by the two promoters, consistent with a model in which the hormone's primary role is to recruit corepressors rather than to clear activators. Nine insulin-responsive TFs are present in both models, but only FoxK1, FoxA2, ZFP91, and ZHX3 require an intact Pck1p insulin response sequence for binding. Knockdown of FoxK1 in primary hepatocytes decreased both glucose production and insulin's ability to suppress it. The findings expand the repertoire of insulin-dependent TFs and identify FoxK1 as a contributor to insulin signaling.

Tumor Cell Subtypes Based on the Intracellular Hormonal Activity in KCNJ5-Mutated Aldosterone-Producing Adenoma

Aldosterone-producing adenomas (APAs) harbor marked intratumoral heterogeneity in terms of morphology, steroidogenesis, and genetics. However, an association of biological significance of morphologically identified tumor cell subtypes and genotypes is virtually unknown. KCNJ5 mutation is most frequently detected and generally considered a curable phenotype by adrenalectomy. Therefore, to explore the biological significance of KCNJ5 mutation in APA based on intracellular hormonal activities, 35 consecutively selected APAs (n=18; KCNJ5 mutated, n=17; wild type) were quantitatively examined in the whole tumor areas by newly developed digital image analysis incorporating their histological and ultrastructural features (14 cells from 2 KCNJ5-mutated APAs and 15 cells from 1 wild type) and CYP11B2 immunoreactivity. Results demonstrated that KCNJ5-mutated APAs had significantly lower nuclear/cytoplasm ratio and more abundant clear cells than wild type. CYP11B2 immunoreactivity was not significantly different between these genotypes, but a significant correlation was detected between the proportion of clear cells and CYP11B2 immunoreactivity in all of the APAs examined. CYP11B2 was predominantly immunolocalized in clear cells in KCNJ5-mutated APAs. Quantitative ultrastructural analysis revealed that KCNJ5-mutated APAs had significantly more abundant and smaller-sized mitochondria with well-developed cristae than wild type, whereas wild type had more abundant lipid droplets per unit area despite the small number of the cases examined. Our results did provide the novel insights into the morphological features of APA based on their biological significance. KCNJ5-mutated APAs were characterized by predominance of enlarged lipid-rich clear cells possibly resulting in increased neoplastic aldosterone biosynthesis.

Aldosterone Suppression by Dexamethasone in Patients With KCNJ5-Mutated Aldosterone-Producing Adenoma

CONTEXT

Aldosterone biosynthesis is regulated principally by ACTH and gene mutations as well as by angiotensin II and serum potassium. In addition, previous studies have reported the potential effects of KCNJ5 mutations in aldosterone-producing adenoma (APA) on cardiovascular diseases. However, responsiveness to ACTH in APAs according to potassium inwardly rectifying channel, subfamily J, member 5 (KCNJ5) mutations remains unknown.

OBJECTIVE

To investigate KCNJ5 genotype-specific differences in aldosterone biosynthesis in response to ACTH stimulation.

DESIGN AND SETTING

A cross-sectional study through retrieval of clinical records.

PARTICIPANTS

One hundred forty-one patients aged ≥20 years with APA were examined.

MAIN OUTCOME MEASURES

Associations between KCNJ5 mutations and clinical parameters reflecting the renin-angiotensin system [saline infusion test (SIT)] and ACTH pathways [dexamethasone suppression test (DST)].

RESULTS

KCNJ5 mutations were detected in 107 cases. In the crude comparison, patients with mutations in KCNJ5 had higher plasma aldosterone concentrations (PACs) both at baseline and after the SIT. PAC after the DST showed a significant inverse association with KCNJ5 genotypes after controlling for age, sex, tumor size, and PAC after the SIT. Immunohistochemical analysis of 101 cases revealed more abundant immunoreactivity of CYP11B1 and CYP17 in the KCNJ5-mutated group than in the KCNJ5 wild-type group.

CONCLUSION

This report of marked suppression of PAC by dexamethasone in patients with KCNJ5-mutated APAs indicates that such APAs respond to endogenous ACTH more readily than APAs in nonmutated cases. Further molecular and epidemiologic studies are required to validate our results and clarify the clinical effectiveness of the DST for predicting KCNJ5 mutations before adrenalectomy.

Immune-mediated acquired lecithin-cholesterol acyltransferase deficiency: A case report and literature review

BACKGROUND

Recessive inherited disorder lecithin-cholesterol acyltransferase (LCAT) deficiency causes severe hypocholesterolemia and nephrotic syndrome. Characteristic lipoprotein subfractions have been observed in familial LCAT deficiency (FLD) with renal damage.

OBJECTIVE

We described a case of acquired LCAT deficiencies with literature review.

METHODS

The lipoprotein profiles examined by gel permeation-high-performance liquid chromatography (GP-HPLC) and native 2-dimensional electrophoresis before and after prednisolone (PSL) treatment.

RESULTS

Here we describe the case of a 67-year-old man with severely low levels of cholesterol. The serum LCAT activity was undetectable, and autoantibodies against it were detected. The patient developed nephrotic syndrome at the age of 70 years. Renal biopsy revealed not only membranous glomerulonephritis but also lesions similar to those seen in FLD. We initiated PSL treatment, which resulted in remission of the nephrotic syndrome. In GP-HPLC analysis, lipoprotein profile was similar to that of FLD although lipoprotein X level was low. Acquired LCAT deficiencies are extremely rare with only 7 known cases including ours. Patients with undetectable LCAT activity levels develop nephrotic syndrome that requires PSL treatment; cases whose LCAT activity levels can be determined may also develop nephrotic syndrome, but spontaneously recover.

CONCLUSION

Lipoprotein X may play a role in the development of renal impairment in individuals with FLD. However, the effect might be less significant in individuals with acquired LCAT deficiency.

Distinct roles of systemic and local actions of insulin on pancreatic β-cells

OBJECTIVE

Pancreatic β-cell mass and function are critical in glucose homeostasis. Their regulatory mechanisms have been studied principally under experimental conditions of reduced β-cell numbers, such as β-cell ablation and partial pancreatectomy. In the present study, we generated an opposite mouse model with an excessive amount of ectopic β-cells, and analyzed its consequence on β-cell mass and survival.

METHODS

Mice underwent sub-renal transplantation (SRT) of pseudo-islets generated from a pancreatic β-cell line MIN6 or intra-pancreatic transplantation (IPT) of MIN6 cells, and morphological and functional changes of their endocrine pancreata were analyzed. Cellular fate of pancreatic β-cells after transplantation was traced using RipCre:Rosa26-tdTomato mice. By using MIN6 cells, we evaluated the roles of extracellular glucose, membrane potential, and insulin signaling on β-cell survival.

RESULTS

SRT mice developed severe, progressive hypoglycemia associated with marked reduction in insulin-positive (Ins⁺) cell mass and apparent increase in apoptotic Ins⁺ cells. In in vitro experiments of MIN6 cells, insulin signaling blockade potently induced cell death, suggesting that local insulin action is required for β-cell survival. In fact, IPT (i.e. transplantation close to endogenous β-cells) resulted in fewer apoptotic Ins⁺ cells compared with those induced by SRT. On the other hand, β-cell mass was decreased in proportion to the decrease in blood glucose levels in both SRT and IPT mice, suggesting a contribution of hypoglycemia induced by systemic hyperinsulinemia.

CONCLUSION

Insulin plays distinct roles in β-cell survival and β-cell mass regulation through its local and systemic actions on β-cells, respectively.

Laparoscopic Sleeve Gastrectomy Resolves Low GHRP-2-Stimulated Growth Hormone Levels in Obese Patients

Because growth hormone (GH) secretion is reportedly decreased in obese patients, we examined not only the factors associated with the decreased GH secretion but also GH response to the GH-releasing peptide (GHRP)-2-load test before and after laparoscopic gastrectomy (LSG). The study comprised 28 individuals aged 19-65 years [mean body mass index (BMI), 39.4 ± 9.4 kg/m²]. In the univariate analysis, GH secretion peaks correlated negatively with BMI (r = -0.59, p = 0.001), visceral adipose tissue (r = -0.47, p = 0.005), and subcutaneous adipose tissue (r = -0.40, p = 0.04). In the two obese patients, the response to the GHRP-2-load test markedly improved by weight loss 12 months after LSG. In conclusion, GH secretion was decreased in obese patients and improved by LSG.

Outcomes of laparoscopic sleeve gastrectomy in elderly obese Japanese patients

AIM

Laparoscopic sleeve gastrectomy (LSG) has proven to be the most effective strategy for the treatment of morbid obesity, however its efficacy and safety in an aging population has not yet been confirmed. In this study, we evaluated the effectiveness and safety of LSG in elderly obese Japanese patients.

METHODS

Three obese individuals aged >60 years and 11 obese individuals aged <60 years who underwent LSG were enrolled. Pre- and postoperative changes after at least 12 months were examined, including bodyweight, body mass index, total weight loss, excess weight loss, bone mineral density and bone-related markers.

RESULTS

There were no significant differences between patients aged <60 years and >60 years in terms of percent total weight loss (24.4 ± 11 vs 23 ± 4.4%, respectively) and percent excess weight loss (49.1 ± 23.4 vs 47.6 ± 10 %, respectively). Dual-energy X-ray absorptiometry was carried out before and 12 months after LSG. There were no significant differences in bone mineral density changes at the lumbar spine and femoral neck between the two groups (0.01 ± 0.06 vs 0.02 ± 0.03 g/cm² , -0.03 ± 0.06 vs -0.08 ± 0.02 g/cm² , respectively). There were no peri- and postoperative complications. All three patients aged >60 years had reduced bone mineral density in the femoral neck after LSG; one was diagnosed with osteoporosis.

CONCLUSIONS

Although the present results suggest that LSG could be of considerable benefit to elderly obese Japanese patients, long-term careful observation after bariatric surgery is especially important in elderly patients to prevent future osteoporosis. Geriatr Gerontol Int 2017; 17: 2068-2073.

Specific clinical signs and symptoms are predictive of clinical course in sporadic Creutzfeldt-Jakob disease

Background and purpose

Akinetic mutism is thought to be an appropriate therapeutic end‐point in patients with sporadic Creutzfeldt−Jakob disease (sCJD). However, prognostic factors for akinetic mutism are unclear and clinical signs or symptoms that precede this condition have not been defined. The goal of this study was to identify prognostic factors for akinetic mutism and to clarify the order of clinical sign and symptom development prior to its onset.

Methods

The cumulative incidence of akinetic mutism and other clinical signs and symptoms was estimated based on Japanese CJD surveillance data (455 cases) collected from 2003 to 2008. A proportional hazards model was used to identify prognostic factors for the time to onset of akinetic mutism and other clinical signs and symptoms.

Results

Periodic synchronous discharges on electroencephalography were present in the majority of cases (93.5%). The presence of psychiatric symptoms or cerebellar disturbance at sCJD diagnosis was associated with the development of akinetic mutism [hazard ratio (HR) 1.50, 95% confidence interval (CI) 1.14–1.99, and HR 2.15, 95% CI1.61–2.87, respectively]. The clinical course from cerebellar disturbance to myoclonus or akinetic mutism was classified into three types: (i) direct path, (ii) path via pyramidal or extrapyramidal dysfunction and (iii) path via psychiatric symptoms or visual disturbance.

Conclusions

The presence of psychiatric symptoms or cerebellar disturbance increased the risk of akinetic mutism of sCJD cases with probable MM/MV subtypes. Also, there appear to be sequential associations in the development of certain clinical signs and symptoms of this disease.

Clinical and Steroidogenic Characteristics of Aldosterone-Producing Adenomas With ATPase or CACNA1D Gene Mutations

OBJECT

This comparative study clarified the clinical characteristics and in vitro steroidogenic activities of aldosterone-producing adenomas (APAs) harboring ATPase or CACNA1D gene mutations.

DESIGN AND PATIENTS

Genetic testing was performed on 159 unilateral APAs. Somatic ATPase and CACNA1D gene mutations were analyzed in 42 APA tissues without KCNJ5 gene mutations.

RESULTS

ATP1A1, ATP2B3, and CACNA1D mutations were detected in one, four, and four patients, respectively. Compared with patients without KCNJ5, ATPase, or CACNA1D mutations (wild type), ATPase mutations tended to have more severe hyperaldosteronism and smaller tumors; those with CACNA1D mutations had clinical characteristics and tumor sizes similar to those with wild-type genes. APAs with ATPase mutations were composed mainly of compact eosinophilic tumor cells, whereas CACNA1D mutations resulted in predominantly clear tumor cells. Aldosterone production in APA cells with ATP2B3 mutations were more responsive to dibutyryl cAMP, whereas those with CACNA1D mutations were more responsive to adrenocorticotropic hormone than the wild-type cells.

CONCLUSION

APAs with ATPase mutations demonstrated a potentially severe primary aldosteronism phenotype, whereas those with CACNA1D mutations displayed characteristics similar to wild-type APAs. The status of stimulated aldosterone production was also different according to the cell types, suggesting that the regulatory effects of adrenocorticotropic hormone on aldosterone synthesis could possibly vary according to the intracellular signaling involved in hormone production.

Abstract P001: Comparative Study on Steroidgenic Activity in Aldosterone-Producing Adenoma With ATPase or CACNA1D Gene Mutations in Japanese Patients With Primary Aldosteronism

Object: Our aim is to clarify the regulatory mechanism of aldosterone synthesis in patients with aldosterone-producing adenomas (APA) harboring ATPase or CACNA1D gene mutations.

Design and patients: We subjected 108 patients with unilateral APA, and tested somatic mutations by using each APA tissue. ATPase and CACNA1D genes were analyzed among 33 APAs without KCNJ5 gene mutations. We also evaluated pathological findings of steroidgenic enzymes and isolated cells prepared from 2 ATP2B3- and 1 CACNA1D-mutated APAs were incubated with various stimulants for clarifying steroidgenic activity.

Results: There were 1, 2, and 2 cases whose APAs possessed ATP1A1, ATP2B3, and CACNA1D mutations, respectively. Compared with the wild-type group without any somatic mutations of KCNJ5, ATPase or CACNA1D, the patients with ATPase mutations showed severe phenotype of hyperaldosteronemia even with smaller-sized tumors, although the CACNA1D-mutated APA patients showed similar characteristics. Pathological findings clearly demonstrated that the ATPase-mutated APA was mainly composed of compact eosinophilic tumor cells, while the CACNA1D-mutated APA mainly did of clear tumor cells with relatively weak 3βHSD2 immunoreactivity. In vitro incubation study with isolated APA cells demonstrated that aldosterone production of ATP2B3 mutated APA cells was more responsive to (Bt)2cAMP than that of the other types of cells (almost 2-fold in the wild group and the CACNA1D-mutated cells vs. 4-fold increase in the ATPase-mutated cells). On the other hand, CACNA1D-mutated APA cells showed greater responsiveness to ACTH compared with the other types of cells (almost 2-fold in the wild group and ATPase-mutated cells vs. 4-fold increase in the CACNA1D-mutated cells).

Conclusion: Responsiveness of aldosterone production stimulated by ACTH or cyclic AMP differed in each case with different cell types. The mutation of ATPase seems to promote accelerated intracellular Ca signaling systems, of which activation may be quantitatively differed in the case of CACNA1D mutation. Thus, our data suggested that the regulatory effect of ACTH on aldosterone synthesis might vary according to the basal intracellular conditions, such as upregulation of Ca signaling induced by each mutation.

Abstract 279: Involvement of Kcnj5 Mutations on Excessive Aldosterone Sythesis When Incubated With Acth by Cells Isolated From Aldosterone-producing Adenoma

Objective: Our objective was to investigate the steroidogenic activity by in vitro incubating adrenocortical cells, isolated from aldosterone- producing adenomas (APA) tissues with/without mutations of the KCNJ5 gene in order to clarify the mechanisms of autonomous production of aldosterone in patients with primary aldosteronism (PA).

Design and Patients: We subjected 22 cases with APA and sequenced KCNJ5 cDNA by using resected tissues of APA. We divided them to 16 APAs with mutations of the KCNJ5 gene (mutated group) and 6 APAs without its mutations (wild type group). Isolated cells were prepared soon after removing APA tissues, and the cells were incubated with various stimulants, including ACTH and Bt2cAMP. The mRNA expression of each steroidogenic enzyme was also determined by RT-PCR.

Results: Responsiveness of aldosterone production (A-P) by isolated cells to ACTH and Bt2cAMP was greater in the mutated group than in the wild type group, although basal amount of A-P incubated for 2hrs without any stimulants was equal between two groups. Responsiveness of A-P to TPA and TPA+ Ca ionophore was greater in the mutated group than in the wild type group. Tissue extracts of mRNA without any stimulations revealed that the mutated group demonstrated higher expression of 17-hydroxylase/3HSD2 than the wild type group, which showed greater expression of CYP11B2 than the mutated group.

Conclusion: In vitro incubation studies demonstrated that ACTH might play a crucial role on up-regulating autonomous production of A-P in APA tissues with mutations of the KCNJ5 gene, although the basal expression of CYP11B2 was lower in the mutated group. Moreover, the mutated group showed high ratio of the basal expression of 17-hydroxylase/3HSD2, suggesting that the mutated group can produce cortisol rather than aldoterone via supplying 17-hydroxylated substrates at the static condition, while cAMP-dependent systems or C-kinase-dependent systems activated by ACTH seem to strongly promote activation of A-P steps in the mutated group, rather than in the wild type group.

Construction of recombinant monoclonal antibodies from a chicken hybridoma line secreting specific antibody

The chicken is a useful animal for the development of the specificantibodies against the mammalian conserved proteins. We generated twotypes of recombinant chicken monoclonal antibodies (mAbs), using a phagedisplay technique from a chicken hybridoma HUC2-13 which secreted themAb to the N-terminal of the mammalian prion protein (PrP). Althoughthe mAb HUC2-13 is a useful antibody for the prion research, thehybridoma produces a low level of antibody production. In order to producea large amount of the mAb, we have constructed a single chain fragmentvariable region (scF(V)) mAb by using the variable heavy(V(H)) and light (V(L))genes which were amplified by using the two primer pairs and theflexible linker. The two phage display mAbs (HUC2p3 and HUC2p5)expressed on a M13 filamentous phage and their soluble type mAbs(HUC2s3 and HUC2s5) were reacted with the PrP peptide antigen in theELISA. In the Western blot analysis, the mAbs HUC2p3 and HUC2s3 wereas reactive to PrP(c) from mouse brains as the mAb HUC2-13 was. The nucleotide sequences of V(H) and V(L) genes from HUC2-13 and the two cloneswere identical except for only one residue. These results indicate that themethods presented here provide an effective tool for the improvement ofthe low levels of antibody production in the chicken hybridoma system.

Actions of the Japanese Pancreas and Islet Transplantation Association regarding transplanted human islets isolated using Liberase HI

PURPOSE

The potential for introducing transmissible spongiform encephalopathy (TSE) into islet cells was indicated by recognizing that Liberase HI is isolated from Clostridium histolyticum grown in media containing brain-heart infusion broth. A national team within the Japanese Pancreas and Islet Transplantation Association implemented an islet transplantation program in Japan using Liberase HI. The program comprised 65 islet isolations from non-heart-beating donors and 34 transplants into 18 patients. Herein, we have summarized how the Association followed these recipients over the long term.

PROCEDURES

We established an ad hoc committee to follow recipients transplanted with islets isolated using Liberase HI after becoming informed of the associated dangers of using this enzyme. We also stopped islet transplantations using Liberase. The committee addressed the major concerns of the risk of the collagenase being contaminated with TSE and of the recipient follow-up. All recipients were examined by diffusion MRI and EEG and then scheduled for evaluation and follow-up by specialists in Creutzfeldt-Jakob disease (CJD). Bioassays of bovine spongiform encephalopathy prions in the enzyme proceeded using knock-in mice expressing bovine prion protein. These assays could detect contaminating prions at a dilution of 1 × 10(4). After inactivating its collagenase activity, Liberase HI was injected into the abdominal cavities of knock-in mice. Four months later, prion infectivity in Liberase HI was evaluated by immunohistochemical staining and Western blotting of spleen homogenates using anti-prion protein antibodies.

MAIN FINDINGS

Western blotting and immunohistochemical staining did not detect prions in Liberase HI. Diffusion MRI and EEG evaluations performed by CJD specialists confirmed that none of the transplanted recipients had CJD.

CONCLUSIONS

Three years of follow-up revealed that none of the Japanese recipients of islet transplants developed CJD. Prion bioassays showed that the Liberase HI used to isolate islets for transplantation was free of infectious TSE prions.

Survival to akinetic mutism state in Japanese cases of MM1-type sporadic Creutzfeldt-Jakob disease is similar to Caucasians

BACKGROUND

It is not known whether the clinical course of Japanese sporadic Creutzfeldt-Jakob disease (sCJD) cases differs from that of Caucasian sCJD cases.

PATIENTS AND METHODS

To investigate the clinical course of Japanese sCJD, clinical findings from 29 patients with Japanese MM1-type sCJD were retrospectively evaluated and compared to Caucasian sCJD findings.

RESULTS

Survival of Japanese MM1-type sCJD up to the time of akinetic mutism state is similar to that of Caucasian subjects. However, the total disease duration of Japanese patients was approximately three times longer.

CONCLUSIONS

The present observations indicate that Japanese sCJD cases generally show a longer disease duration because of the longer survival period after reaching the akinetic mutism state.

Differential expression of CD44 variants among meningioma subtypes

Aims/background-CD44 is a widely distributed cell surface molecule which has numerous isoforms generated by alternative splicing. The diverse functions related to the CD44 variants (CD44v) have been reported in various physiological and pathological conditions. The pattern of expression of CD44v among meningioma subtypes was investigated to ascertain whether CD44 variants play a role in a variety of biological processes, such as epithelial differentiation and extracranial metastasis.Methods-Twenty three meningiomas were studied immunohistochemically using novel antibodies directed against CD44 isoforms. Six of the 23 samples were analysed by reverse transcription polymerase chain reaction (RT-PCR), followed by Southern blotting with CD44v specific probes.Results-In meningothelial, fibrous and anaplastic meningiomas, a standard form of CD44 was detected by RT-PCR and was homogeneously expressed in tumour cells when studied immunohistochemically. CD44v was not detected in these subtypes. In secretory meningiomas, however, CD44v isoforms were strongly expressed in the cell clusters that produce secretory granules and also accumulated in the granules. The population of tumour cells immunopositive for CD44v was similar to that which stained with antibodies directed against carcinoembryonic antigen, epithelial membrane antigen and ezrin. On RT-PCR with Southern blotting, only the secretory type showed high level expression of CD44v.Conclusions-CD44v in meningiomas is expressed in relation to tumour cell differentiation towards the epithelial type.

Less protease-resistant PrP in a patient with sporadic CJD treated with intraventricular pentosan polysulphate

Treatment with intraventricular pentosan polysulphate (PPS) might be beneficial in patients with Creutzfeldt-Jakob disease. We report a 68-year-old woman with sporadic Creutzfeldt-Jakob disease who received continuous intraventricular PPS infusion (1-120 microg/kg/day) for 17 months starting 10 months after the onset of clinical symptoms. Treatment with PPS was well tolerated but was associated with a minor, transient intraventricular hemorrhage and a non-progressive collection of subdural fluid. The patient's overall survival time was well above the mean time expected for the illness but still within the normal range. Post-mortem examination revealed that the level of abnormal protease-resistant prion protein in the brain was markedly decreased compared with levels in brains without PPS treatment. These findings suggest that intraventricular PPS infusion might modify the accumulation of abnormal prion proteins in the brains of patients with sporadic Creutzfeldt-Jakob disease.