Secondary diabetes associated with principal endocrinopathies: the impact of new treatment modalities

Doughnut-shaped bimetallic Cu-Zn-MOF with peroxidase-like activity for colorimetric detection of glucose and antibacterial applications

Metal-organic frameworks (MOFs), especially bimetallic MOFs, have attracted widespread attention for simulating the structure and function of natural enzymes. In this study, different morphologies of bimetallic Cu-Zn-MOF with different peroxidase (POD)-like activities were prepared by simply controlling the molar ratio of Cu2+ and Zn2+. Among them, the doughnut-shaped Cu9-Zn1-MOF exhibited the largest POD-like activity. Cu9-Zn1-MOF was combined with glucose oxidase to construct a sensitive and selective glucose colorimetric biosensor with a linear detection range of 10-300 μM and a detection limit of 7.1 μm. Furthermore, Cu9-Zn1-MOF can efficiently convert hydrogen peroxide (H2O2) into hydroxyl radicals that effectively kill both gram-negative and gram-positive bacteria at low H2O2 level. The results of this study may promote the synthesis of bimetallic MOFs and broaden their applications in the biomedical field.

Comparison of adrenalectomy with conservative treatment on mild autonomous cortisol secretion: a systematic review and meta-analysis

Objective

This systematic review and meta-analysis was conducted to compare the benefits of adrenalectomy and conservative treatment for comorbidities associated with mild autonomous cortisol secretion (MACS) in patients diagnosed with MACS.

Background

MACS is the most common benign hormone-secreting functional adrenal incidentaloma. Overproduction of cortisol is observed in MACS patients, resulting in a variety of long-term health issues, including arterial hypertension (HTN), diabetes mellitus (DM), dyslipidemia, obesity, and osteoporosis; however, the classic clinical manifestations of Cushing's syndrome (CS) are not present.

Methods

A systematic search was conducted using MEDLINE, Embase, Web of Sciences, and Scopus databases on December, 2023. Two reviewers independently extracted data and assessed the quality of the included articles. A meta-analysis was performed to compare the beneficial effects of adrenalectomy versus conservative management for MACS-related comorbidities.

Results

Fifteen articles were included in this study, which evaluated 933 MACS patients (384 Adrenalectomy and 501 Conservative treatment, and 48 excluded due to incomplete follow-up duration). MACS diagnosis criteria were different among the included articles. All studies, however, stated that there must be no overt CS symptoms. Meta-analysis demonstrates the overall advantage of adrenalectomy over conservative treatment for MACS-related comorbidities (Cohen's d = -0.49, 95% CI [-0.64, -0.34], p = 0.00). Subgroup analysis indicated that the systolic blood pressure (pooled effect size = -0.81, 95% CI [-1.19, -0.42], p = 0.03), diastolic blood pressure (pooled effect size = -0.63, 95% CI [-1.05, -0.21], p = 0.01), and BMD (pooled effect size = -0.40, 95% CI [-0.73, -0.07], p = 0.02) were significantly in favor of adrenalectomy group rather than conservative treatment but no significant differences between the two treatment groups in other MACS-related comorbidities were reported.

Conclusion

Despite the limited and diverse data, this study demonstrates the advantage of adrenalectomy over conservative treatment for MACS-related comorbidities.

Gluconeogenesis Flux in Metabolic Disease

Gluconeogenesis is a critical biosynthetic process that helps maintain whole-body glucose homeostasis and becomes altered in certain medical diseases. We review gluconeogenic flux in various medical diseases, including common metabolic disorders, hormonal imbalances, specific inborn genetic errors, and cancer. We discuss how the altered gluconeogenic activity contributes to disease pathogenesis using data from experiments using isotopic tracer and spectroscopy methodologies. These in vitro, animal, and human studies provide insights into the changes in circulating levels of available gluconeogenesis substrates and the efficiency of converting those substrates to glucose by gluconeogenic organs. We highlight ongoing knowledge gaps, discuss emerging research areas, and suggest future investigations. A better understanding of altered gluconeogenesis flux may ultimately identify novel and targeted treatment strategies for such diseases.

Diabetes Mellitus Secondary to Endocrine Diseases: An Update of Diagnostic and Treatment Particularities

Secondary diabetes mellitus is frequently ignored in specialized literature. In this narrative review, the main endocrinopathies accompanied by increased glycemic values are identified, as well as the mechanisms by which the excess or deficiency of certain hormones impact beta cell function or insulin resistance. The main endocrinopathies (acromegaly, Cushing's syndrome, Basedow-Graves' disease, pheochromocytoma, somatostatinoma and glucagonoma) and their characteristics are described along with the impact of hormone changes on blood sugar, body mass index and other parameters associated with diabetes. The overall information regarding the complex molecular mechanisms that cause the risk of secondary diabetes and metabolic syndrome is of crucial importance in order to prevent the development of the disease and its complications and particularly to reduce the cardiovascular risk of these patients. The purpose of this study is to highlight the particular features of endocrine pathologies accompanied by an increased risk of developing diabetes, in the context of personalized therapeutic decision making. The epidemiological, physiopathological, clinical and therapeutic approaches are presented along with the importance of screening for diabetes in endocrine diseases.

Glucose metabolism, gut-brain hormones, and acromegaly treatment: an explorative single centre descriptive analysis

PURPOSE

Active acromegaly is associated with impaired glucose metabolism, which improves upon treatment. Treatment options include surgery, medical therapy with somatostatin analogues (SSA) and Pegvisomant (PEG), and irradiation. The objective of the study was to describe the differential effect of various treatment regimens on the secretion of glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) in patients with acromegaly.

METHODS

23 surgically treated, non-diabetic patients with acromegaly and 12 healthy controls underwent an oral glucose tolerance test (OGTT) and subsequently isoglycaemic intravenous glucose infusion on a separate day. Baseline hormone concentrations, time-to-peak and area under the curve (AUC) on the OGTT-day and incretin effect were compared according to treatment regimens.

RESULTS

The patients treated with SSA (N = 15) had impaired GIP-response (AUC, P = 0.001), and numerical impairment of all other hormone responses (P > 0.3). Patients co-treated with PEG (SSA + PEG, N = 4) had increased secretion of insulin and glucagon compared to patients only treated with SSA (SSA ÷ PEG, N = 11) (insulin_AUC mean ± SEM, SSA + PEG 49 ± 8.3 nmol/l*min vs SSA ÷ PEG 25 ± 3.4, P = 0.007; glucagon_AUC, SSA + PEG 823 ± 194 pmol/l*min vs SSA ÷ PEG 332 ± 69, P = 0.009). GIP secretion remained significantly impaired, whereas GLP-1 secretion was numerically increased with PEG (SSA + PEG 3088 ± 366 pmol/l*min vs SSA ÷ PEG 2401 ± 239, P = 0.3). No difference was found in patients treated with/without radiotherapy nor substituted or not with hydrocortisone.

CONCLUSION

SSA impaired the insulin, glucagon, and incretin hormone secretions. Co-treatment with PEG seemed to counteract the somatostatinergic inhibition of the glucagon and insulin response to OGTT. We speculate that PEG may exert its action through GH-receptors on pancreatic δ-cells. Clinical trial registration NCT02005978.

Prevalence of hypersomatotropism and hyperthyroidism in cats with diabetes mellitus from referral centers in Buenos Aires (2020-2022)

OBJECTIVES

The aim of this study was to estimate the prevalence of hypersomatotropism (HST) and hyperthyroidism in cats with diabetes mellitus (DM) from referral centers in Buenos Aires, Argentina.

METHODS

This was a prospective study. Systematic screening of serum insulin-like growth factor 1 (IGF-1) and total thyroxine was performed in all cats diagnosed with DM at referral centers in Buenos Aires between February 2020 and February 2022.

RESULTS

In total, 154 diabetic cats were evaluated (99 males and 55 females; median age 12 years [range 3-21]; mean body weight 5 kg [range 2-12]). Altogether, there were 115 (75%) domestic shorthairs and one domestic longhair; the remaining 38 cats were purebred (mainly Siamese, n = 25 [16%]). Twenty (12.9%) cats had IGF-1 concentrations >1000 ng/ml, and three (1.9%) had IGF-1 concentrations between 800 and 1000 ng/ml along with pituitary enlargement on CT, resulting in a 14.9% HST prevalence rate in diabetic cats. Intracranial imaging was performed in all cats with HST; median pituitary dorsoventral height was 5.8 mm (range 3.1-9.5). Fourteen of 23 (61%) cats had phenotypic changes consistent with acromegaly at the time of diagnosis of HST. Four of 154 (2.5%) cats had concurrent hyperthyroidism.

CONCLUSIONS AND RELEVANCE

To date, this is the first study outside of Europe to have evaluated the prevalence of HST and hyperthyroidism in cats with DM. In Buenos Aires referral centers, feline HST is the most common concurrent endocrinopathy in cats with DM but with a lower prevalence than has previously been reported. Hyperthyroidism is a rare concurrent endocrinopathy in diabetic cats from referral centers in Buenos Aires.

Metabolic disorders during endogenous Cushing's syndrome: prevalence, associated factors, and outcome after remission

Objective. The prognosis of Cushing's syndrome (CS) is related to a higher cardiovascular morbidity and mortality. This study aimed to determine the prevalence of metabolic disorders in patients with CS, the associated factors, and the rate of remission of these disorders after the remission from CS. Methods. It is a retrospective study including 75 cases of CS followed up at the university hospital La Rabta of Tunis from 1987 to 2018. Clinical and paraclinical data were collected from medical files. Results. The mean age of the patients was 44.1±18.9 years and the sex ratio was 0.39. At CS diagnosis, the frequencies of obesity, hypertension, diabetes, dyslipidemia, and metabolic syndrome were 52, 75, 43, 83, and 73%, respectively. The age, gender, body mass index, waist circumference, and baseline serum cortisol level were not associated with the presence of diabetes, hypertension or dyslipidemia. Forty-eight patients were operated on. At one year, 38 patients were in remission from CS. The remission rates of hypertension, diabetes, and dyslipidemia were respectively 58% (p<0.001), 76% (p<0.001), and 17% (NS). Conclusion. Metabolic disorders were frequent during CS and their frequencies decreased after the remission from the syndrome.

The progression of secondary diabetes: A review of modeling studies

Mathematical modeling has provided quantitative information consistent with experimental data, greatly improving our understanding of the progression of type 1 and type 2 diabetes. However, diabetes is a complex metabolic disease and has been found to be involved in crosstalk interactions with diverse endocrine diseases. Mathematical models have also been developed to investigate the quantitative impact of various hormonal disorders on glucose imbalance, advancing the precision treatment for secondary diabetes. Here we review the models established for the study of dysglycemia induced by hormonal disorders, such as excessive glucocorticoids, epinephrine, and growth hormone. To investigate the influence of hyperthyroidism on the glucose regulatory system, we also propose a hyperthyroid-diabetes progression model. Model simulations indicate that timely thyroid treatment can halt the progression of hyperglycemia and prevent beta-cell failure. This highlights the diagnosis of hormonal disorders, together withblood sugar tests, as significant measures for the early diagnosis and treatment of diabetes. The work recapitulates updated biological research on the interactions between the glucose regulatory system and other endocrine axes. Further mathematical modeling of secondary diabetes is desired to promote the quantitative study of the disease and the development of individualized diabetic therapies.

Application of Nanoparticles: Diagnosis, Therapeutics, and Delivery of Insulin/Anti-Diabetic Drugs to Enhance the Therapeutic Efficacy of Diabetes Mellitus

Diabetes mellitus (DM) is a chronic metabolic disorder of carbohydrates, lipids, and proteins due to a deficiency of insulin secretion or failure to respond to insulin secreted from pancreatic cells, which leads to high blood glucose levels. DM is one of the top four noncommunicable diseases and causes of death worldwide. Even though great achievements were made in the management and treatment of DM, there are still certain limitations, mainly related to the early diagnosis, and lack of appropriate delivery of insulin and other anti-diabetic agents. Nanotechnology is an emerging field in the area of nanomedicine and NP based anti-diabetic agent delivery is reported to enhance efficacy by increasing bioavailability and target site accumulation. Moreover, theranostic NPs can be used as diagnostic tools for the early detection and prevention of diseases owing to their unique biological, physiochemical, and magnetic properties. NPs have been synthesized from a variety of organic and inorganic materials including polysaccharides, dendrimers, proteins, lipids, DNA, carbon nanotubes, quantum dots, and mesoporous materials within the nanoscale size. This review focuses on the role of NPs, derived from organic and inorganic materials, in the diagnosis and treatment of DM.

Long-term morbidity and mortality in patients with Cushing's syndrome

Increased multisystem morbidity and mortality in patients with Cushing's syndrome comprise clinical problems and challenges, both at the time of diagnosis and in remission. Relevant comorbidities and clinical problems include hypertension, diabetes, overweight, myopathy and a high risk for acute complications such as infections and venous thrombembolism. Although there are therapy recommendations for most of these comorbidities, there is a lack of large, prospective studies to confirm and optimise them. Mortality is especially high during active disease and within the first year after diagnosis, as a result of cardiovascular events, infections and suicide. All in all, interdisciplinary therapy management is important for reducing morbidity and mortality over the long-term.

Change of Computed Tomography-Based Body Composition after Adrenalectomy in Patients with Pheochromocytoma

Despite the potential biological importance of the sympathetic nervous system on fat and skeletal muscle metabolism in animal and in vitro studies, its relevance in humans remains undetermined. To clarify the influence of catecholamine excess on human body composition, we performed a retrospective longitudinal cohort study including 313 consecutive patients with histologically confirmed pheochromocytoma who underwent repeat abdominal computed tomography (CT) scans before and after adrenalectomy. Changes in CT-determined visceral fat area (VFA), subcutaneous fat area (SFA), skeletal muscle area (SMA), and skeletal muscle index (SMI) were measured at the level of the third lumbar vertebra. The mean age of all patients was 50.6 ± 13.6 years, and 171/313 (54.6%) were women. The median follow-up duration for repeat CTs was 25.0 months. VFA and SFA were 14.5% and 15.8% higher, respectively (both p < 0.001), after adrenalectomy, whereas SMA and SMI remained unchanged. Similarly, patients with visceral obesity significantly increased from 103 (32.9%) at baseline to 138 (44.1%) following surgery (p < 0.001); however, the prevalence of sarcopenia was unchanged. This study provides important clinical evidence that sympathetic hyperactivity can contribute to lipolysis in visceral and subcutaneous adipose tissues, but its impact on human skeletal muscle is unclear.

Approach to Diagnosing a Pediatric Patient With Severe Insulin Resistance in Low- or Middle-income Countries

Diabetes mellitus (DM) in children is most often caused by impaired insulin secretion (type 1 DM). In some children, the underlying mechanism for DM is increased insulin resistance, which can have different underlying causes. While the majority of these children require insulin dosages less than 2.0 U/kg/day to achieve normoglycemia, higher insulin requirements indicate severe insulin resistance. Considering the therapeutic challenges in patients with severe insulin resistance, early diagnosis of the underlying cause is essential in order to consider targeted therapies and to prevent diabetic complications. Although rare, several disorders can attribute to severe insulin resistance in pediatric patients. Most of these disorders are diagnosed through advanced diagnostic tests, which are not commonly available in low- or middle-income countries. Based on a case of DM with severe insulin resistance in a Surinamese adolescent who was later confirmed to have autosomal recessive congenital generalized lipodystrophy, type 1 (Berardinelli-Seip syndrome), we provide a systematic approach to the differential diagnosis and work-up. We show that a thorough review of medical history and physical examination generally provide sufficient information to diagnose a child with insulin-resistant DM correctly, and, therefore, our approach is especially applicable to low- or middle-income countries.

The β Cell in Diabetes: Integrating Biomarkers With Functional Measures

The pathogenesis of hyperglycemia observed in most forms of diabetes is intimately tied to the islet β cell. Impairments in propeptide processing and secretory function, along with the loss of these vital cells, is demonstrable not only in those in whom the diagnosis is established but typically also in individuals who are at increased risk of developing the disease. Biomarkers are used to inform on the state of a biological process, pathological condition, or response to an intervention and are increasingly being used for predicting, diagnosing, and prognosticating disease. They are also proving to be of use in the different forms of diabetes in both research and clinical settings. This review focuses on the β cell, addressing the potential utility of genetic markers, circulating molecules, immune cell phenotyping, and imaging approaches as biomarkers of cellular function and loss of this critical cell. Further, we consider how these biomarkers complement the more long-established, dynamic, and often complex measurements of β-cell secretory function that themselves could be considered biomarkers.

Surgical Remission of Diabetes in a Patient With Mutation of RET Proto-Oncogene

OBJECTIVE

In pheochromocytomas, accelerated catecholamine production can cause secondary diabetes. The gene responsible for multiple endocrine neoplasia type 2 (MEN2)-related pheochromocytomas is the RET proto-oncogene. The objective of this report is to describe a unique case of surgical remission of misdiagnosed type 2 diabetes mellitus (T2DM) in a woman with bilateral pheochromocytoma and RET proto-oncogene mutation.

METHODS

Clinical examination, urinary metanephrine level, triple-phase abdominal computed tomography (CT) with adrenal protocol, positron emission tomography with ¹⁸F-fluorodeoxyglucose integrated with CT, surgical pathology, and genetic testing were performed.

RESULTS

A 46-year-old woman with a 5-year history of apparent T2DM complicated by neuropathy, without a contributory family history, presented with occasional headaches, weight loss, and abdominal pain. A 24-hour urinary metanephrine of 5 mg (reference range, 0.05-1 mg) was found. Abdominal CT showed bilateral adrenal masses with <60% washout. Positron emission tomography with ¹⁸F-fluorodeoxyglucose integrated with CT showed a left solid-cystic lesion with low metabolic activity and a right nodular lesion with a higher metabolic activity, which was conclusive of bilateral pheochromocytoma. The remission of diabetes was achieved 1 year after a bilateral adrenalectomy. In addition, a multinodular goiter was found, and a fine-needle aspiration biopsy confirmed that it was a medullary thyroid carcinoma. A heterozygous pathogenic variant of the RET proto-oncogene was found and MEN2A was confirmed.

CONCLUSION

This is the first report of a patient with a RET proto-oncogene mutation experiencing remission of diabetes after surgical resection of bilateral pheochromocytomas. Timely recognition and treatment of the underlying condition are important to potentially achieve diabetes remission and prevent its long-term complications.

A preliminary evaluation of the circulating leptin/adiponectin ratio in dogs with pituitary-dependent hyperadrenocorticism and concurrent diabetes mellitus

Leptin and adiponectin are thought to modulate insulin sensitivity and pancreatic β-cell function, but there is limited information regarding the adipokine status of hyperglycemic dogs with hyperadrenocorticism. This study aimed to determine whether alterations in the leptin/adiponectin ratio, insulin sensitivity, and/or pancreatic β-cell function are associated with diabetes mellitus (DM) in dogs with pituitary-dependent hyperadrenocorticism (PDH). A total of 48 client-owned dogs were included in this prospective observational study: 20 dogs with PDH (10 normoglycemic and 10 with DM), 15 dogs with DM, and 13 healthy dogs. The serum concentrations of leptin, adiponectin, resistin, interleukin (IL)-1β, IL-6, IL-10, IL-18, and tumor necrosis factor (TNF)-α were measured, and homeostatic model assessment indices (HOMAs) were calculated and compared among the groups. Serum leptin was significantly higher in PDH dogs with and without DM than in healthy and DM dogs, and it was lower in DM dogs than in PDH dogs without DM. Serum adiponectin was significantly lower in PDH dogs with DM than in healthy and PDH dogs, and it was significantly lower in DM dogs than in healthy dogs. Serum IL-10 was significantly higher in PDH dogs with DM than in healthy and PDH dogs without DM. The leptin/adiponectin ratio was significantly higher in PDH dogs with DM than in normoglycemic PDH dogs. Serum IL-6 concentrations were significantly higher in DM dogs than in healthy dogs. Serum IL-1β concentration was significantly higher in DM dogs than in healthy dogs and PDH dogs with DM and without DM. Serum TNF-α and IL-18 concentrations were not different among groups. The HOMA_{β-cell function} was significantly lower in PDH dogs with DM than in normoglycemic PDH dogs, while HOMA_{insulin sensitivity} was significantly lower in PDH dogs with DM than in healthy dogs. These results suggest that adipokine dysregulation, a reduction in insulin sensitivity, and a further impairment in pancreatic β-cell function might predispose PDH dogs to DM. Further longitudinal study will be necessary to confirm this result.

Status and clinical and radiological predictive factors of presurgical anterior pituitary function in pituitary adenomas. Study of 232 patients

PURPOSE

To investigate the status of preoperative anterior pituitary function in patients undergoing pituitary adenoma (PA) resection and to identify factors associated with preoperative anterior pituitary dysfunction (APD).

METHODS

Patients with functioning and nonfunctioning PAs who underwent pituitary adenoma resection for first time, from January 2009 to December 2019 were analyzed.

RESULTS

Total sample included 232 patients; 123 (53.2%) females, mean age at diagnosis was 53.3 years. Sixty-three percent presented as nonfunctioning PAs and 37.1% as functioning PAs. Eighty-eight percent were macroadenomas and 34.9% had cavernous sinus invasion. APD was demonstrated in 36.2% (n = 84) of the patients. The FSH/LH deficit was the most frequent anterior pituitary deficit (31.9%); followed by ACTH (18.1%); TSH (16.4%) and GH (13.8%). We identified as independent risk factors of APD, male sex (OR = 6.1, 95% CI = 3.3-11.0); age (OR = 1.03 for each year, 95% CI = 1.01-1.04), diabetes mellitus (OR = 3.5, 95% CI = 1.63-7.69), pituitary apoplexy presentation (OR = 4.3, 95% CI = 1.3-14.5) and tumor size (OR = 1.06 for each mm, 95% CI = 1.04-1.09). Nonfunctioning PAs (NFPA) had higher risk of APD than functioning PAs (FPA) (OR = 2.8 (95% CI = 1.5-5.0), but these differences disappeared after adjusted by tumor size (OR adjusted by tumor size = 1.7, 95% CI = 0.9-3.3). The tumor size with the highest diagnostic accuracy to predict hypopituitarism was 22 mm (sensitivity of 61.9% and specificity of 70.1%).

CONCLUSION

More than one third of PAs candidates for surgery had APD. The male sex, diabetes, an older age, pituitary apoplexy, and larger PAs were risk factors of APD. Hence, in these patients, the hormonal study should be prioritized and the need for dynamic tests must be carefully assessed.

Pathophysiology of diabetes: An overview

Diabetes mellitus is a chronic heterogeneous metabolic disorder with complex pathogenesis. It is characterized by elevated blood glucose levels or hyperglycemia, which results from abnormalities in either insulin secretion or insulin action or both. Hyperglycemia manifests in various forms with a varied presentation and results in carbohydrate, fat, and protein metabolic dysfunctions. Long-term hyperglycemia often leads to various microvascular and macrovascular diabetic complications, which are mainly responsible for diabetes-associated morbidity and mortality. Hyperglycemia serves as the primary biomarker for the diagnosis of diabetes as well. In this review, we would be focusing on the classification of diabetes and its pathophysiology including that of its various types.

Role of growth hormone signaling pathways in the development of atherosclerosis

OBJECTIVE

The direct actions of growth hormone (GH) in the development of atherosclerosis are unclear. The goal of this study was to characterize GH-induced changes in expression of signaling pathway elements and other proteins that may be related to atherosclerosis.

METHODS

Human umbilical vein endothelial cells (HUVEC) and THP-1, a human acute monocytic leukemia cell line, were stimulated by exposure to 10^-9 M or 10^-8 M human GH with or without pretreatment with a mitogen-activated protein kinase kinase (MEK) 1 inhibitor. Levels of transcripts encoding vascular cell adhesion molecule (VCAM) -1, E-selectin, monocyte chemotactic protein (MCP-1), interleukin (IL) -6, and IL-8 were investigated by reverse transcription (RT) -PCR. For the quantitative adhesion assay, THP-1 cells or human primary monocytes were fluorescently labeled with 3'-O-acetyl-2',7'-bis(carboxyethyl) -4 diacetoxymethyl ester (BCECF/AM). HUVEC treated with human GH were co-incubated with BCECF-labeled THP-1 cells. One hour later, the number of BCECF-labeled THP-1 cells was assessed. An equivalent experiment was performed using BCECF-labeled primary monocytes, and the number of monocytes adhering to HUVEC was counted.

RESULTS

Treatment with hGH increased the levels of E-selectin- and VCAM-1-encoding mRNAs in HUVEC. This effect was attenuated by pretreatment with a MEK1 inhibitor. Furthermore, hGH treatment increased adhesion of BCECF-labeled THP-1 cells or primary monocytes to HUVEC, and this effect was attenuated by pretreatment with a MEK1 inhibitor.

CONCLUSIONS

VCAM-1 and E-selectin expression was stimulated by GH via the mitogen-activated protein kinase pathway, resulting in augmented adhesion of THP-1 cells and monocytes to HUVEC. These data suggested that GH directly stimulates the development of atherosclerosis.

Peanut skin extract ameliorates the symptoms of type 2 diabetes mellitus in mice by alleviating inflammation and maintaining gut microbiota homeostasis

In this study, mice with type 2 diabetes mellitus (T2DM) induced by high-fat diet were used to investigate the antidiabetic effect and mechanism of action of peanut skin extract (PSE). Results revealed that the fasting blood glucose, body weight, and food intake of mice with T2DM significantly decreased after they were given PSE. The effects of 80 mg/kg PSE were similar to those of 140 mg/kg metformin (MET). The glucose tolerance and insulin sensitivity of the mice also improved. The composition of intestinal microflora in the mice significantly changed after PSE administration. In particular, no Actinobacteria was detected in the PSE-treated group, and the ratio of Firmicutes to Bacteroidetes was remarkably reduced. PSE also increased the abundance of gut microbiota involved in fatty acid biosynthesis, lipid biosynthesis, and sucrose metabolism. The abundance of gut microbiota related to aminoacyl-tRNA biosynthesis also decreased. Lipopolysaccharide, interleukin (IL)-6, IL-1β and tumor necrosis factor-α in the blood, liver and adipose tissue were reduced by PSE. Similarly, the mRNA expression levels of IkappaB kinase and nuclear factor kappaB in the hypothalamus were reduced by PSE. These results suggested that PSE and MET elicited significant antidiabetic effects by maintaining gut microbiota and inhibiting inflammation.

Genetic predisposition in type 2 diabetes: A promising approach toward a personalized management of diabetes

Diabetes mellitus, also known simply as diabetes, has been described as a chronic and complex endocrine metabolic disorder that is a leading cause of death across the globe. It is considered a key public health problem worldwide and one of four important non-communicable diseases prioritized for intervention through world health campaigns by various international foundations. Among its four categories, Type 2 diabetes (T2D) is the commonest form of diabetes accounting for over 90% of worldwide cases. Unlike monogenic inherited disorders that are passed on in a simple pattern, T2D is a multifactorial disease with a complex etiology, where a mixture of genetic and environmental factors are strong candidates for the development of the clinical condition and pathology. The genetic factors are believed to be key predisposing determinants in individual susceptibility to T2D. Therefore, identifying the predisposing genetic variants could be a crucial step in T2D management as it may ameliorate the clinical condition and preclude complications. Through an understanding the unique genetic and environmental factors that influence the development of this chronic disease individuals can benefit from personalized approaches to treatment. We searched the literature published in three electronic databases: PubMed, Scopus and ISI Web of Science for the current status of T2D and its associated genetic risk variants and discus promising approaches toward a personalized management of this chronic, non-communicable disorder.

The association between physical activity, sleep, and quality of life in patients in bio-chemical remission from Cushing's syndrome

PURPOSE

Cushing's syndrome can negatively affect patient's quality of life (QoL) after treatment and remission. Exposure to increased cortisol over time can result in visceral obesity, which makes this population vulnerable to cardiovascular risk factors associated with visceral obesity. Sleep disturbances are present in patients in remission from Cushing's syndrome, impacting QoL. Moderate intensity physical activity performed 3 times a week decreases visceral obesity and improves sleep quality, therefore, engaging in physical activity after remission may improve patient's QoL. The current study aims to explore the association between sleep quality, physical activity, and QoL in patients in remission of Cushing's syndrome.

METHODS

Patients in bio-chemical remission from Cushing's syndrome (N = 147) were recruited through the Cushing's Support and Research Foundation. Quality of life was assessed using the Cushing Quality of Life Questionnaire (CushingQoL), sleep was assessed with the Pittsburgh Sleep Quality Index (PSQI), and physical activity levels were assessed with the Godin-Sheppard Leisure-Time Physical Activity Questionnaire (GSLTPAQ).

RESULTS

Sleep quality was significantly associated with both subscales of the CushingQoL (both p < .001), but physical activity was not significantly associated with either subscale. Sleep was not significantly associated with physical activity engagement in this sample.

CONCLUSION

Results suggest that patients in remission from Cushing's syndrome experience sleep disturbances that are significantly associated with impaired QoL. Future research should focus on ameliorating the persisting clinical features of Cushing's syndrome that are associated with impaired QoL after bio-chemical remission to improve QoL and expedite complete functional remission.

Change of skeletal muscle mass in patients with pheochromocytoma

The effects of catecholamine excess due to pheochromocytoma on body composition, including skeletal muscle mass, are unknown. Here, we investigated the effects of catecholamine metabolites on body composition in subjects with pheochromocytoma. After body compositions using bioelectrical impedance analysis, urinary metanephrine (UM), and urinary normetanephrine (UNM) were measured in 16 patients with pheochromocytoma and 224 patients with nonfunctioning adrenal incidentaloma (NFAI), we compared skeletal muscle mass and fat mass (FM) between the two groups. After adjustments for confounders, UM (β = - 0.171, P = 0.006) and UNM (β = - 0.249, P < 0.001) levels were correlated inversely with skeletal muscle mass index (SMI), but not FM or percentage FM (pFM), in all subjects. Patients with pheochromocytoma had lower ASM by 7.7% (P = 0.022) and SMI by 6.6% (P = 0.001) than patients with NFAI. Conversely, FM and pFM were not statistically different between the two groups. The odds ratio for low skeletal muscle mass in the presence of pheochromocytoma was 10.33 (95% confidence interval, 2.65-40.22). Our results indicate that patients with pheochromocytoma have a reduced skeletal muscle mass and suggest that catecholamine excess has adverse effects on skeletal muscle metabolism.

Cardiovascular events in patients with over 10 years history of type 2 diabetes mellitus

BACKGROUND

Diabetes is one of the concerns of today's public health and patients with type 2 diabetes are at increased risk of death due to cardiovascular diseases. The aim of this study was to evaluate the prevalence of cardiovascular diseases in patients with over 10 years history of type 2 diabetes mellitus referred to the Sanandaj Diabetes Clinic.

METHODS

In this study, 400 patients with type 2 diabetes who had over 10 years history of diabetes were selected and the required information was prepared based on taking their history and files. Finally data were analyzed using T-test, Chi-square and Fisher test methods.

RESULTS

In this the mean duration of diabetes was 14.59 ± 4.07 years. 95.25% of patients had dyslipidemia. The frequency of history of cardiovascular events was 78.25%. 12.25% of patients had a history of ischemic heart disease and 82.75% had a history of high blood pressure. There was a significant relationship between the incidence of cardiovascular events with hypertension, HDL level and family history of early cardiovascular disease (p < 0.05).

CONCLUSION

The high risk of cardiovascular events in diabetic patients it strongly emphasizes the need for quick and serious approaches to prevent cardiovascular events in diabetic patients.

ECHOCARDIOGRAPHIC MYOCARDIAL CHANGES IN ACROMEGALY: A CROSS-SECTIONAL ANALYSIS IN A TERTIARY CENTER IN BULGARIA

Context

Cardiomyopathy is the most frequent cardiovascular complication in acromegaly.

Objective

We aimed to compare some echocardiographic markers in acromegaly patients with controls and find a correlation with disease duration, disease activity, levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1).

Design

We conducted a cross-sectional case-control study for the period of 2008-2012.

Subjects and methods

Acromegaly patients altogether 146 (56 men and 90 women), were divided into four groups according to disease activity and the presence of arterial hypertension (AH). The control group included 83 subjects, matching the patient groups by age, gender and presence of AH. GH was measured by an immunofluorometric method, while IGF-1 by IRMA method. All patients and controls were subjected to one- and two-dimensional transthoracic echocardiography, color and pulse Doppler.

Results

We found a thickening of the left ventricular walls and an increase in the left ventricular mass. However, these changes were not statistically significant in all groups and no correlation with disease duration could be demonstrated. As markers of diastolic dysfunction, increased deceleration time and isovolumetric relaxation were registered, which were dependent mainly on age in a binary logistic regression analysis, but not GH or IGF-1. Using absolute values, ejection and shortening fractions were increased in some groups. Using cut-off values, a higher percentage of systolic dysfunction was demonstrated in patients compared to their corresponding controls. Engagement of the right heart ventricle was also found - increased deceleration time and decreased e/a tric ratio.

Conclusions

In conclusion, functional impairments of both ventricles were present, with a predominance of left ventricular diastolic dysfunction.

A Comparison of Biomarkers in the Assessment of Glycemic Control in Diabetes: Reviewing the Evidence

BACKGROUND

Diabetes Mellitus (DM) is a chronic life-long progressive multisystem heterogeneous metabolic disorder with complex pathogenesis.

INTRODUCTION

Hyperglycemia is not only one of the classical signs of DM, but it also serves as the pivotal prerequisite for the diagnosis of the disease. However, with the advancement in the field of analytical biochemistry, a number of alternative and specific biomarkers have been discovered which can be used for better diagnosis of the DM. In this review, we have discussed various aspects of DM and different biomarkers used in assessing glycemia.

METHODOLOGY

A thorough literature survey was conducted to identify various studies that reported the use of conventional and non-conventional markers for the assessment of glycemia in DM patients.

CONCLUSION

The accurate detection and hence diagnosis of DM has become easy and more specific with the use of various biomarkers.

Effect of cabergoline monotherapy in Cushing's disease: an individual participant data meta-analysis

CONTEXT

The primary treatment of choice for Cushing's disease (CD) is the removal of the pituitary adenoma by transsphenoidal surgery (TSS). The surgical failure is seen in up to 75% of cases depending on the experience of the surgeon in different studies. Medical therapy is one of the options for the treatment of recurrent or persistent CD.

METHODOLOGY

The primary outcome of this meta-analysis was to find the proportion of patients achieving normalisation of 24-h urinary free cortisol (remission of CD) following cabergoline monotherapy. Literature search was conducted in January 2018 in PubMed/MEDLINE database from its date of inception to 31st December 2017. The search strategy used was "[(cushing) OR Cushing's] AND cabergoline". Individual participant data were extracted from the included studies and risk of bias was analysed by review checklist proposed by MOOSE.

RESULTS

The individual participant data of 124 patients from six observational studies were included in this meta-analysis. 92 patients (74.2%) had past pituitary surgery. The proportion of patients achieving remission of Cushing’s disease (CD) with cabergoline monotherapy was 34% (95% confidence interval 0.26–0.43; P = 0.001) [corrected]. The previous surgery [odds ratio (OR) 28.4], duration of cabergoline monotherapy (OR 1.31) and maximum cabergoline dose (OR 0.19) were predictors for remission of CD. Mild and severe side effects were reported in 37.3% and 5.6% of patients, respectively, during cabergoline monotherapy.

CONCLUSIONS

This meta-analysis shows that cabergoline monotherapy is a reasonable alternative for subjects with persistent or recurrent CD after TSS. It can also be used in CD patients either as a bridge therapy while waiting for surgery or in those unwilling for surgery or have contraindication to it.

Should Cushing's Syndrome be Considered as a Disease with High Cardiovascular Risk in Relevant Guidelines?

A considerable amount of data supports a 1.8-7.4-fold increased mortality associated with Cushing's syndrome (CS). This is attributed to a high occurrence of several cardiovascular disease (CVD) risk factors in CS [e.g. adiposity, arterial hypertension (AHT), dyslipidaemia and type 2 diabetes mellitus (T2DM)]. Therefore, practically all patients with CS have the metabolic syndrome (MetS), which represents a high CVD risk. Characteristically, despite a relatively young average age, numerous patients with CS display a 'high' or 'very high' CVD risk (i.e. risk of a major CVD event >20% in the following 10 years). Although T2DM is listed as a condition with a high CVD risk, CS is not, despite the fact that a considerable proportion of the CS population will develop T2DM or impaired glucose tolerance. CS is also regarded as a risk factor for aortic dissection in current guidelines. This review considers the evidence supporting listing CS among high CVD risk conditions.

Diabetes and pancreatic neuroendocrine tumours: Which interplays, if any?

Pancreatic neuroendocrine tumours (PanNETs) represent an uncommon type of pancreatic neoplasm, whose incidence is increasing worldwide. As per exocrine pancreatic cancer, a relationship seems to exist between PanNETs and glycaemic alterations. Diabetes mellitus (DM) or impaired glucose tolerance often occurs in PanNET patients as a consequence of hormonal hypersecretion by the tumour, specifically affecting glucose metabolism, or due to tumour mass effects. On the other hand, pre-existing DM may represent a risk factor for developing PanNETs and is likely to worsen the prognosis of such patients. Moreover, the surgical and/or pharmacological treatment of the tumour itself may impair glucose tolerance, as well as antidiabetic therapies may impact tumour behaviour and patients outcome. Differently from exocrine pancreatic tumours, few data are available for PanNETs as yet on this issue. In the present review, the bidirectional association between glycaemic disorders and PanNETs has been extensively examined, since the co-existence of both diseases in the same individual represents a further challenge for the clinical management of PanNETs.

The management of neuroendocrine tumours: A nutritional viewpoint

Nutritional status in patients with neuroendocrine tumours (NETs), especially of gastroenteropancreatic origin, can be deeply affected by excessive production of gastrointestinal hormones, peptides, and amines, which can lead to malabsorption, diarrhoea, steatorrhea, and altered gastrointestinal motility. Besides, the surgical and/or medical management of NETs can lead to alteration of gastrointestinal secretory, motor, and absorptive functions, with both dietary and nutritional consequences. Indeed, disease-related malnutrition is a frequently encountered yet both underrecognized and understudied clinical phenomenon in patients with NETs, with substantial prognostic and socioeconomic consequences. Most of these conditions can be alleviated by a tailored nutritional approach, also with the aim of improving the efficacy of cancer treatments. In this setting, skilled nutritionists can play a fundamental role in the multidisciplinary health care team in NETs management and their presence should be recommended. The aim of this review is to provide dietary advices for each specific condition in patients with NETs, underlining the importance of a nutritional approach to treat malnutrition in this setting. Further, we will provide preliminary evidence coming from our data on the assessment of nutritional status in a single cohort of patients with NETs.

Coexistence of GH-Producing Pituitary Macroadenoma and Meningioma in a Patient with Multiple Endocrine Neoplasia Type 1 with Hyperglycemia and Ketosis as First Clinical Sign

We present the clinical case of a patient who was admitted with an onset of diabetes mellitus (DM) with associated ketosis and whose clinical, hormonal, and radiological evolution revealed the presence of primary hyperparathyroidism, pancreatic neuroendocrine tumor, and GH-producing pituitary macroadenoma in the context of multiple endocrine neoplasia type 1 (MEN1). DM is relatively common in cases of acromegaly, but it is not generally associated with ketosis. Simultaneously, the patient presented a meningioma, which is associated with pituitary macroadenoma only in extremely rare cases.

Utility of baseline serum phosphorus levels for predicting remission in acromegaly patients

PURPOSE

High GH and IGF I levels increase tubular phosphate reabsorption in patients with acromegaly. We aimed to investigate the utility of serum phosphorus levels as an indicator for predicting chance of remission in acromegaly patients.

DESIGN

Fifty-one patients (n: 51; F: 24, M: 27) with diagnosis of acromegaly were included in the study. Plasma IGF-1, Phosphorus (P) and nadir GH levels on oral glucose tolerance test (OGTT) at the time of diagnosis were analysed retrospectively. Patients were classified into two groups according to their plasma P levels; P ≤ 4.5 mg/dl (Group-1, n: 23, 45.1%), P > 4.5 mg/dl (Group-2, n: 28, 54.9%). Two groups were compared according to remission status; remission (n: 27) and non-remission (n: 24). Remission was defined with absence of clinical symptoms, normal plasma IGF-1 (adjusted for age and gender) and GH levels (<1 mcg/dl) at least 3 months after initial treatment.

RESULTS

Serum P levels decreased significantly after treatment in both groups (p < 0.001). There was a significant correlation between baseline phosphorus levels and remission rates, nadir GH in OGTT, pituitary adenoma size and Ki-67 scores (p = 0.001, r: -0.51; p = 0.01, r: 0.44; p = 0.001, r: 0.52; p = 0.02, r: 0.71, respectively). Mean baseline P levels were significantly higher in patients with non-remission (4.8 vs 4.2, P < 0.001). Logistic regression analysis did not reveal an independent effect on remission with any of these risk factors.

CONCLUSION

High serum P levels may be an indicator for a low likelihood of onset of remission in acromegaly patients. Further studies with wider spectrum are needed to make specific suggestions.

Concurrent hyperadrenocorticism and diabetes mellitus in dogs

Hyperadrenocorticism (HAC) and diabetes mellitus (DM) are two diseases that can occur concurrently in dogs. The objective of this study was to evaluate the coexistence of HAC and DM, and the risk factors involved that could contribute to the development of DM in dogs with HAC. A total of 235 dogs with HAC were studied and, according to their fasting glycemia, they were divided into three groups: <5.6mmol/L, between 5.6 and 10.08mmol/L and >10.08mmol/L. The following parameters were evaluated: age, gender, cause of HAC, body condition, glycemia, total cholesterol, triglycerides, urinary cortisol:creatinin ratio (UCCR) and survival time. A 13.61% concurrence of HAC and DM was observed. Dogs with a fasting glycemia >5.6mmol/L, with dislipemia, with Pituitary-Dependent Hyperadrenocorticism, UCCR >100×10^-6 and non-castrated females showed a higher risk of developing DM. The development of DM in dogs with HAC reduces the survival time.

Obesity, metabolic syndrome and diabetic retinopathy: Beyond hyperglycemia

Diabetic retinopathy (DR) is the most feared ocular manifestation of diabetes. DR is characterized by progressive retinal damage that may eventually result in blindness. Clinically, this blindness is caused by progressive damage to the retinal microvasculature, which leads to ischemia, retinal swelling, and neovascularization. Retinopathy is associated with both type 1 and type 2 diabetes, with DR being the leading cause of new onset blindness in United States adults. Despite this strong association with diabetes, it must be noted that the development of retinopathy lesions is multifactorial and may occur in individuals without an established history of diabetes. Metabolic syndrome is a multifactorial condition of central obesity, hypertriglyceridemia, dyslipidemia, hypertension, fasting hyperglycemia, and insulin resistance. Although several studies examined the individual components observed in the metabolic syndrome in relation to the development of DR, there is conflicting data as to the association of the metabolic syndrome with the development of retinopathy lesions in non-diabetic subjects. This review will summarize the current literature on the evidence of the metabolic syndrome on retinopathy in subjects with and without an established history of diabetes. This review will also discuss some of the mechanisms through which metabolic syndrome can contribute to the development of retinopathy.

DISCORDANCE BETWEEN GH AND IGF-1 LEVELS IN TURKISH ACROMEGALIC PATIENTS

OBJECTIVE

Discordance between insulin-like growth factor-1 (IGF-1) and growth hormone (GH) levels is an important problem in the follow-up of patients diagnosed with acromegaly. Our aims were to evaluate the discordance between IGF-1 and GH levels and compare the performance of different cut-off levels for the nadir in GH (GHn) in acromegalic patients.

METHODS

The study included 63 acromegalic patients in a follow-up at a tertiary care university hospital facility. Levels of IGF-1, IGF binding protein-3 (IGFBP-3), and GH were investigated. The baseline GH and GHn levels were evaluated after an oral glucose tolerance test (cut-offs of 0.4 and 1 ng/mL, respectively). The discordance rates between GHn and IGF-1 levels, and IGF-1/IGFBP-3 ratios were determined.

RESULTS

We first adopted a GHn cut-off value of 1 ng/mL and found that 27 patients (42.9%) exhibited biochemical remission (BR) (IGF-1 <95^th percentile, GH <1), and 25 patients (39.7%) had no BR (NBR) (IGF-1 ≥95^th percentile, GH >1). Discordance in the presence of normal IGF-1 and nonsuppressed GH (DC1) occurred in 2 of 63 (3.2%) patients; discordance in the presence of high IGF-1 and suppressed GH (DC2) occurred in 9 of 63 (14.3%) patients. If the GHn cut-off value adopted was 0.4 ng/mL, the distributions were 17 of 63 (27.0%) patients in BR, 29 of 63 (46.0%) patients in NBR, 12 of 63 (19.0%) in DC1, and 5 of 63 (7.9%) patients in DC2. If only the baseline GH values were considered, the distributions were very similar to those with a GHn cut-off value of 0.4 ng/mL. The IGF-1/IGFBP-3 ratio was lowest in the BR group.

CONCLUSION

Adopting a GHn cut-off value of 0.4 ng/mL did not increase the test performance compared with baseline GH only. In contrast, in the follow-up of acromegalic patients, the IGF-1/IGFBP-3 ratio might be a useful measurement when discordance between IGF-1 and GH levels occurs. We propose that these values be considered in clinical practice.

ABBREVIATIONS

BR = biochemical remission DC1 = discordance group 1 DC2 = discordance group 2 DM = diabetes mellitus GH = growth hormone GHn = nadir in GH IGF-1 = insulin-like growth factor-1 IGFBP-3 = IGF binding protein-3 LAR = long-acting release NBR = not in biochemical remission OGTT = oral glucose tolerance test.

Current and Emerging Aspects of Diabetes Mellitus in Acromegaly

Diabetes mellitus is a frequent complication of acromegaly, a disease characterized by chronic hypersecretion of growth hormone (GH) by a pituitary adenoma. Diabetes occurs commonly but not only as a consequence of an insulin-resistant state induced by GH excess. The development of diabetes in patients with acromegaly is clinically relevant, since such a complication is thought to increase the already elevated cardiovascular morbidity and mortality risk of the disease. Emerging data suggest that a specific cardiomyopathy can be identified in acromegaly patients with diabetes. Moreover, the presence of diabetes may also influence therapeutic decision making in acromegaly, since traditional and newly developed drugs used in this clinical setting may impact glucose metabolism regardless of control of GH hypersecretion.

The Possible Role of mRNA Expression Changes of GH/IGF-1/Insulin Axis Components in Subcutaneous Adipose Tissue in Metabolic Disturbances of Patients With Acromegaly

We explored the effect of chronically elevated circulating levels of growth hormone (GH)/insulin-like-growth-factor-1 (IGF-1) on mRNA expression of GH/IGF-1/insulin axis components and p85alpha subunit of phosphoinositide-3-kinase (p85alpha) in subcutaneous adipose tissue (SCAT) of patients with active acromegaly and compared these findings with healthy control subjects in order to find its possible relationships with insulin resistance and body composition changes. Acromegaly group had significantly decreased percentage of truncal and whole body fat and increased homeostasis model assessment-insulin resistance (HOMA-IR). In SCAT, patients with acromegaly had significantly increased IGF-1 and IGF-binding protein-3 (IGFBP-3) expression that both positively correlated with serum GH. P85alpha expression in SCAT did not differ from control group. IGF-1 and IGFBP-3 expression in SCAT were not independently associated with percentage of truncal and whole body fat or with HOMA-IR while IGFBP-3 expression in SCAT was an independent predictor of insulin receptor as well as of p85alpha expression in SCAT. Our data suggest that GH overproduction in acromegaly group increases IGF-1 and IGFBP-3 expression in SCAT while it does not affect SCAT p85alpha expression. Increased IGF-1 or IGFBP-3 in SCAT of acromegaly group do not appear to contribute to systemic differences in insulin sensitivity but may have local regulatory effects in SCAT of patients with acromegaly.

Glucocorticoids Inhibit Basal and Hormone-Induced Serotonin Synthesis in Pancreatic Beta Cells

Diabetes is a major complication of chronic Glucocorticoids (GCs) treatment. GCs induce insulin resistance and also inhibit insulin secretion from pancreatic beta cells. Yet, a full understanding of this negative regulation remains to be deciphered. In the present study, we investigated whether GCs could inhibit serotonin synthesis in beta cell since this neurotransmitter has been shown to be involved in the regulation of insulin secretion. To this aim, serotonin synthesis was evaluated in vitro after treatment with GCs of either islets from CD1 mice or MIN6 cells, a beta-cell line. We also explored the effect of GCs on the stimulation of serotonin synthesis by several hormones such as prolactin and GLP 1. We finally studied this regulation in islet in two in vivo models: mice treated with GCs and with liraglutide, a GLP1 analog, and mice deleted for the glucocorticoid receptor in the pancreas. We showed in isolated islets and MIN6 cells that GCs decreased expression and activity of the two key enzymes of serotonin synthesis, Tryptophan Hydroxylase 1 (Tph1) and 2 (Tph2), leading to reduced serotonin contents. GCs also blocked the induction of serotonin synthesis by prolactin or by a previously unknown serotonin activator, the GLP-1 analog exendin-4. In vivo, activation of the Glucagon-like-Peptide-1 receptor with liraglutide during 4 weeks increased islet serotonin contents and GCs treatment prevented this increase. Finally, islets from mice deleted for the GR in the pancreas displayed an increased expression of Tph1 and Tph2 and a strong increased serotonin content per islet. In conclusion, our results demonstrate an original inhibition of serotonin synthesis by GCs, both in basal condition and after stimulation by prolactin or activators of the GLP-1 receptor. This regulation may contribute to the deleterious effects of GCs on beta cells.

Preoperative octreotide therapy and surgery in acromegaly: associations between glucose homeostasis and treatment response

In acromegaly, high GH/IGF-1 levels associate with abnormal glucose metabolism. Somatostatin analogs (SSAs) reduce GH and IGF-1 but inhibit insulin secretion. We studied glucose homeostasis in de novo patients with acromegaly and changes in glucose metabolism after treatment with SSA and surgery. In this post hoc analysis from a randomized controlled trial, 55 de novo patients with acromegaly, not using antidiabetic medication, were included. Before surgery, 26 patients received SSAs for 6 months. HbA1c, fasting glucose, and oral glucose tolerance test were performed at baseline, after SSA pretreatment and at 3 months postoperative. Area under curve of glucose (AUC-G) was calculated. Glucose homeostasis was compared to baseline levels of GH and IGF-1, change after SSA pretreatment, and remission both after SSA pretreatment and 3 months postoperative. In de novo patients, IGF-1/GH levels did not associate with baseline glucose parameters. After SSA pretreatment, changes in GH/IGF-1 correlated positively to change in HbA1c levels (both p < 0.03). HbA1c, fasting glucose, and AUC-G increased significantly during SSA pretreatment in patients not achieving hormonal control (all p < 0.05) but did not change significantly in patients with normalized hormone levels. At 3 months postoperative, HbA1c, fasting glucose, and AUC-G were significantly reduced in both cured and not cured patients (all p < 0.05). To conclude, in de novo patients with acromegaly, disease activity did not correlate with glucose homeostasis. Surgical treatment of acromegaly improved glucose metabolism in both cured and not cured patients, while SSA pretreatment led to deterioration in glucose homeostasis in patients not achieving biochemical control.

Metabolic comorbidities in Cushing's syndrome

Cushing's syndrome (CS) patients have increased mortality primarily due to cardiovascular events induced by glucocorticoid (GC) excess-related severe metabolic changes. Glucose metabolism abnormalities are common in CS due to increased gluconeogenesis, disruption of insulin signalling with reduced glucose uptake and disposal of glucose and altered insulin secretion, consequent to the combination of GCs effects on liver, muscle, adipose tissue and pancreas. Dyslipidaemia is a frequent feature in CS as a result of GC-induced increased lipolysis, lipid mobilisation, liponeogenesis and adipogenesis. Protein metabolism is severely affected by GC excess via complex direct and indirect stimulation of protein breakdown and inhibition of protein synthesis, which can lead to muscle loss. CS patients show changes in body composition, with fat redistribution resulting in accumulation of central adipose tissue. Metabolic changes, altered adipokine release, GC-induced heart and vasculature abnormalities, hypertension and atherosclerosis contribute to the increased cardiovascular morbidity and mortality. In paediatric CS patients, the interplay between GC and the GH/IGF1 axis affects growth and body composition, while in adults it further contributes to the metabolic derangement. GC excess has a myriad of deleterious effects and here we attempt to summarise the metabolic comorbidities related to CS and their management in the perspective of reducing the cardiovascular risk and mortality overall.

Bone density and microarchitecture in endogenous hypercortisolism

OBJECTIVE

Osteoporosis is a serious and underestimated complication of endogenous hypercortisolism that results in an increased risk of fractures, even in patients with normal or slightly decreased bone mineral density (BMD). Alterations in bone microarchitecture, a very important component of bone quality, may explain bone fragility. The aim of this study was to investigate bone density and microarchitecture in a cohort of patients with endogenous Cushing's syndrome (CS).

DESIGN

Cross-sectional study.

PATIENTS

Thirty patients with endogenous active CS and fifty-one age-, sex- and body mass index-matched controls were included.

MEASUREMENTS

Participants were studied for areal BMD (dual-energy X-ray absorptiometry) of the lumbar spine (LS), femoral neck (FN), total femur (TF) and radius (33%), and for volumetric bone density (vBMD) and structure using high-resolution peripheral quantitative computed tomography (HR-pQCT) of the distal radius and distal tibia.

RESULTS

Patients with active CS exhibited lower areal BMD and Z-score values in the LS, FN and TF (P < 0·003 for all comparisons). At HR-pQCT, the patients with CS also had lower cortical area (P = 0·009 at the radius and P = 0·002 at the tibia), lower cortical thickness (P = 0·02 at the radius and P = 0·002 at the tibia), lower cortical density (P = 0·008 at the tibia) and lower total vBMD (P = 0·002 at the tibia). After the exclusion of hypogonadal individuals, the patients with CS maintained the same microarchitectural and densitometric alterations described above.

CONCLUSIONS

Endogenous hypercortisolism has deleterious effects on bone, especially on cortical bone microstructure. These effects seem to be a more important determinant of bone impairment than gonadal status.

Hepatic ALT isoenzymes are elevated in gluconeogenic conditions including diabetes and suppressed by insulin at the protein level

BACKGROUND

Alanine transaminase (ALT) plays an important role in gluconeogenesis by converting alanine into pyruvate for glucose production. Early studies have shown that ALT activities are upregulated in gluconeogenic conditions and may be implicated in the development of diabetes. ALT consists of two isoforms, ALT1 and ALT2, with distinctive subcellular and tissue distributions. Whether and how they are regulated are largely unknown.

METHODS

By using Western blotting analysis, we measured hepatic ALT isoforms at the protein level in obese and diabetic animals and in Fao hepatoma cells treated with dexamethasone and insulin. In addition, we measured glucose output in Fao cells over-expressing ALT1 and ALT2.

RESULTS

Both ALT isoforms in the liver were increased in diabetic Goto-Kakizaki rats and during fasting. However, in ob/ob mice, only ALT2, but not ALT1, protein levels were elevated, and the increase of ALT2 was correlated with that of ALT activity. We further demonstrated that, in vitro, both ALT1 and ALT2 were induced by glucocorticoid dexamethasone, but suppressed by insulin in Fao cells. Finally, we showed that the over-expression of ALT1 and ALT2 in Fao cells directly increased glucose output.

CONCLUSIONS

We have shown the similarity and difference in the regulation of ALT isoforms in gluconeogenic conditions at the protein level, supporting that ALT isoenzymes play an important role in glucose metabolism and may be implicated the development of insulin resistance and diabetes.

Risk of diabetes mellitus among patients with myasthenia gravis

OBJECTIVES

To determine the risk of diabetes mellitus (DM) in patients with myasthenia gravis (MG) in a large cohort representing 99% of the Taiwan population.

METHODS

Data from the Taiwan National Health Insurance Database were used to conduct retrospective cohort analyses. The study cohort comprised 1520 patients with MG who were four-fold frequency matched to those without MG by age and sex, and assigned the same index year. Cox proportional hazard regression analysis was conducted to estimate the risk of DM.

RESULTS

The MG cohort had a 1.26-fold increased risk of developing DM compared with the comparison cohort (HR=1.26, 95% CI=1.04-1.53). MG patients without corticosteroids use had no increased risk of developing DM (HR=1.05, 95% CI=0.79-1.40), and MG patients with corticosteroids use had a 1.46-fold increased risk of developing DM (HR=1.46, 95%=1.15-1.86). In addition, patients with MG received aggressive treatment, associated thyroid diseases, and male patients had higher risk of DM.

CONCLUSION

This population-based retrospective cohort study demonstrates that MG is associated with a high risk of DM, which might be related to the adverse effect of corticosteroid and aggressive therapy.

Genetics, genomics and personalized medicine in Type 2 diabetes: a perspective on the Arab region

Type 2 diabetes (T2D) is a wide-spread, chronic metabolic disorder, affecting millions of people worldwide. The epidemic of diabetes has placed a huge strain on public health, longevity and economy. T2D occurs as a result of both genetic and environmental factors and is heterogeneous in its presentation across individuals. This review gives an overview of the genetic variations identified by genome-wide association studies which predispose individuals to T2D and those which are responsible for variable drug response across patients, and the necessity to adopt a personalized approach to diabetes management. We also include a perspective on diabetes in Arabs, given the high incidence of T2D and consanguineous marriages, and the need to understand associated genetic components in this vulnerable population.

Studying Cat (Felis catus) Diabetes: Beware of the Acromegalic Imposter

Naturally occurring diabetes mellitus (DM) is common in domestic cats (Felis catus). It has been proposed as a model for human Type 2 DM given many shared features. Small case studies demonstrate feline DM also occurs as a result of insulin resistance due to a somatotrophinoma. The current study estimates the prevalence of hypersomatotropism or acromegaly in the largest cohort of diabetic cats to date, evaluates clinical presentation and ease of recognition. Diabetic cats were screened for hypersomatotropism using serum total insulin-like growth factor-1 (IGF-1; radioimmunoassay), followed by further evaluation of a subset of cases with suggestive IGF-1 (>1000 ng/ml) through pituitary imaging and/ or histopathology. Clinicians indicated pre-test suspicion for hypersomatotropism. In total 1221 diabetic cats were screened; 319 (26.1%) demonstrated a serum IGF-1>1000 ng/ml (95% confidence interval: 23.6–28.6%). Of these cats a subset of 63 (20%) underwent pituitary imaging and 56/63 (89%) had a pituitary tumour on computed tomography; an additional three on magnetic resonance imaging and one on necropsy. These data suggest a positive predictive value of serum IGF-1 for hypersomatotropism of 95% (95% confidence interval: 90–100%), thus suggesting the overall hypersomatotropism prevalence among UK diabetic cats to be 24.8% (95% confidence interval: 21.2–28.6%). Only 24% of clinicians indicated a strong pre-test suspicion; most hypersomatotropism cats did not display typical phenotypical acromegaly signs. The current data suggest hypersomatotropism screening should be considered when studying diabetic cats and opportunities exist for comparative acromegaly research, especially in light of the many detected communalities with the human disease.

[Carbohydrate metabolism in patients with acromegaly and Itsenko-Cushing disease]

The relevance of investigating carbohydrate metabolism (CM) in patients with acromegaly and Itsenko-Cushing disease is attributable to frequent glucose metabolic disturbances, on the one hand, and to difficulties in choosing sugar-lowering therapy in these categories of patients, on the other. The efficiency of hyperglycemia treatment in these patients may be reduced due to problems in achieving remission/cure of the underlying disease and to specific therapy favoring hyperglycemia. The top-priority tasks are to search for ways of reducing the frequency of CM abnormalities in patients with neuroendocrine diseases and to elaborate sugar-lowering therapy regimens. There is a growing interest in studies of the role of the incretin system in the pathogenesis of secondary hyperglycemias associated with neuroendocrine diseases. Nevertheless, few works have been published on this subject matter because of its novelty. There is a need for a further closer study of the specific features of incretin system function and the pharmacodynamics of incretin mimetics that are potential candidates as first-line drugs to treat secondary hyperglycemias. This paper attempts to summarize the available data obtained from studies into CM in neuroendocrine diseases.

Delta Cell Hyperplasia in Adult Goto-Kakizaki (GK/MolTac) Diabetic Rats

Reduced beta cell mass in pancreatic islets (PI) of Goto-Kakizaki (GK) rats is frequently observed in this diabetic model, but knowledge on delta cells is scarce. Aiming to compare delta cell physiology/pathology of GK to Wistar rats, we found that delta cell number increased over time as did somatostatin mRNA and delta cells distribution in PI is different in GK rats. Subtle changes in 6-week-old GK rats were found. With maturation and aging of GK rats, disturbed cytoarchitecture occurred with irregular beta cells accompanied by delta cell hyperplasia and loss of pancreatic polypeptide (PPY) positivity. Unlike the constant glucose-stimulation index for insulin PI release in Wistar rats, this index declined with GK age, whereas for somatostatin it increased with age. A decrease of GK rat PPY serum levels was found. GK rat body weight decreased with increasing hyperglycemia. Somatostatin analog octreotide completely blocked insulin secretion, impaired proliferation at low autocrine insulin, and decreased PPY secretion and mitochondrial DNA in INS-1E cells. In conclusion, in GK rats PI, significant local delta cell hyperplasia and suspected paracrine effect of somatostatin diminish beta cell viability and contribute to the deterioration of beta cell mass. Altered PPY-secreting cells distribution amends another component of GK PI's pathophysiology.