Leptin treatment has vasculo-protective effects in lipodystrophic mice.

Lipodystrophy syndromes (LDs) are characterized by loss of adipose tissue, metabolic complications such as dyslipidemia, insulin resistance, and fatty liver disease, as well as accelerated atherosclerosis. As a result of adipose tissue deficiency, the systemic concentration of the adipokine leptin is reduced. A current promising therapeutic option for patients with LD is treatment with recombinant leptin (metreleptin), resulting in reduced risk of mortality. Here, we investigate the effects of leptin on endothelial to mesenchymal transition (EndMT), which impair the functional properties of endothelial cells and promotes atherogenesis in LD. Leptin treatment reduced inflammation and TGF-ß2-induced expression of mesenchymal genes and prevented impairment of endothelial barrier function. Treatment of lipodystrophic- and atherosclerosis-prone animals (Ldlr-/-; aP2-nSrebp1c-Tg) with leptin reduced macrophage accumulation in atherosclerotic lesions, vascular plaque protrusion, and the number of endothelial cells with mesenchymal gene expression, confirming a reduction in EndMT in LD after leptin treatment. Treatment with leptin inhibited LD-mediated induction of the proatherosclerotic cytokine growth/differentiation factor 15 (GDF15). Inhibition of GDF15 reduced EndMT induction triggered by plasma from patients with LD. Our study reveals that in addition to the effects on adipose tissue function, leptin treatment exerts beneficial effects protecting endothelial function and identity in LD by reducing GDF15.

Leptin induces TNFα-dependent inflammation in acquired generalized lipodystrophy and combined Crohn's disease.

Leptin has been shown to modulate intestinal inflammation in mice. However, clinical evidence regarding its immune-stimulatory potential in human Crohn's disease remains sparse. We here describe a patient with the unique combination of acquired generalized lipodystrophy and Crohn's disease (AGLCD) featuring a lack of adipose tissue, leptin deficiency and intestinal inflammation. Using mass and flow cytometry, immunohistochemistry and functional metabolic analyses, the AGLCD patient was compared to healthy individuals and Crohn's disease patients regarding immune cell composition, function and metabolism and the effects of recombinant N-methionylleptin (rLeptin) were evaluated. We provide evidence that rLeptin exerts diverse pro-inflammatory effects on immune cell differentiation and function, including the metabolic reprogramming of immune cells and the induction of TNFα, ultimately aggravating Crohn's disease in the AGLCD patient, which can be reversed by anti-TNFα therapy. Our results indicate that leptin is required for human immune homeostasis and contributes to autoimmunity in a TNFα-dependent manner.

Pregnancy in Women Previously Treated for an Adrenocortical Carcinoma.

CONTEXT: Adrenocortical carcinomas (ACCs) are rare, aggressive tumors, of which some express receptors for estradiol, progesterone, and/or human chorionic gonadotoropin. Because this disease is encountered frequently in young women, pregnancy is a relevant issue. OBJECTIVE: to evaluate the impact of pregnancy on outcome of patients previously treated for ACC. DESIGN/SETTING: retrospective observational multicenter study of the European Network for the Study of Adrenal Tumors. PATIENTS: Seventeen ACC patients (21 pregnancies), becoming pregnant at least 3 months after the initial treatment, were compared with 247 nonpregnant ACC patients less than 47 years old. A control group of 34 patients matched for age, sex, and tumor stage was used for survival analysis. MAIN OUTCOME MEASURE(S): Overall survival, tumors characteristics at diagnosis, pregnancy outcome. RESULTS: All 17 patients with pregnancies had localized ACC. The median time between surgery and conception was 4 years (0.3-12 y). Two pregnancies were terminated at 8 weeks. Sixteen women gave birth to 19 live infants. With exception of 1 (presumably unrelated) cardiac malformation, no severe fetal or maternal complication was observed. After a median follow-up time of 8.36 years and 5.26 years after the first conception, 1 of the 17 patients had died and 5 had experienced a recurrence, among whom 3 occurred before conception. Overall survival was not significantly different between the "pregnancy group" and the matched controls. CONCLUSION: Pregnancy in patients previously treated for ACC seems to not be associated with worse clinical outcome, although a "healthy mother effect" cannot be excluded.

Biochemical diagnosis of phaeochromocytoma using plasma-free normetanephrine, metanephrine and methoxytyramine: importance of supine sampling under fasting conditions.

OBJECTIVE: To document the influences of blood sampling under supine fasting versus seated nonfasting conditions on diagnosis of phaeochromocytomas and paragangliomas (PPGL) using plasma concentrations of normetanephrine, metanephrine and methoxytyramine. DESIGN AND METHODS: Biochemical testing for PPGL was performed on 762 patients at six centres, two of which complied with requirements for supine sampling after an overnight fast and four of which did not. Phaeochromocytomas and paragangliomas were found in 129 patients (67 noncompliant, 62 compliant) and not in 633 patients (195 noncompliant, 438 compliant). RESULTS: Plasma concentrations of normetanephrine and methoxytyramine did not differ between compliant and noncompliant sampling conditions in patients with PPGL but were 49-51% higher in patients without PPGL sampled under noncompliant compared with compliant conditions. The 97·5 percentiles of distributions were also higher under noncompliant compared with compliant conditions for normetanephrine (1·29 vs 0·79 nmol/l), metanephrine (0·49 vs 0·41 nmol/l) and methoxytyramine (0·42 vs 0·18 nmol/l). Use of upper cut-offs established from seated nonfasting sampling conditions resulted in substantially decreased diagnostic sensitivity (98% vs 85%). In contrast, use of upper cut-offs established from supine fasting conditions resulted in decreased diagnostic specificity for testing under noncompliant compared with compliant conditions (71% vs 95%). CONCLUSIONS: High diagnostic sensitivity of plasma normetanephrine, metanephrine and methoxytyramine for the detection of PPGL can only be guaranteed using upper cut-offs of reference intervals established with blood sampling under supine fasting conditions. With such cut-offs, sampling under seated nonfasting conditions can lead to a 5·7-fold increase in false-positive results necessitating repeat sampling under supine fasting conditions.

Risk profiles and penetrance estimations in multiple endocrine neoplasia type 2A caused by germline RET mutations located in exon 10.

Multiple endocrine neoplasia type 2 is characterized by germline mutations in RET. For exon 10, comprehensive molecular and corresponding phenotypic data are scarce. The International RET Exon 10 Consortium, comprising 27 centers from 15 countries, analyzed patients with RET exon 10 mutations for clinical-risk profiles. Presentation, age-dependent penetrance, and stage at presentation of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism were studied. A total of 340 subjects from 103 families, age 4-86, were registered. There were 21 distinct single nucleotide germline mutations located in codons 609 (45 subjects), 611 (50), 618 (94), and 620 (151). MTC was present in 263 registrants, pheochromocytoma in 54, and hyperparathyroidism in 8 subjects. Of the patients with MTC, 53% were detected when asymptomatic, and among those with pheochromocytoma, 54%. Penetrance for MTC was 4% by age 10, 25% by 25, and 80% by 50. Codon-associated penetrance by age 50 ranged from 60% (codon 611) to 86% (620). More advanced stage and increasing risk of metastases correlated with mutation in codon position (609→620) near the juxtamembrane domain. Our data provide rigorous bases for timing of premorbid diagnosis and personalized treatment/prophylactic procedure decisions depending on specific RET exon 10 codons affected.

Pancreatic neuroendocrine tumor with ectopic adrenocorticotropin production upon second recurrence.

We present a 54-yr-old woman with ectopic corticotropin syndrome caused by a neuroendocrine tumor of the pancreas. At initial presentation, the patient suffered from diarrhea, heartburn, and nonspecific abdominal pain. There was no evidence of Cushing's syndrome. A neuroendocrine tumor in the head of the pancreas with metastases into peripancreatic lymph nodes was diagnosed and completely resected. Fourteen months later, abdominal computed tomography and scintigraphy with (111)In-labeled octreotide suggested relapse of the tumor. The patient again had no evidence of Cushing's syndrome. A second in toto tumor resection was performed. Another 8 months later, the patient developed forgetfulness, depressive episodes, muscle weakness, new-onset hypertension, hypokalemia, plethora, diabetes mellitus, polyuria, and weight loss. Endocrine testing suggested a source of ectopic ACTH production. An octreotide scan showed an intense uptake ventromedial of the left kidney, an area that showed a mass lateral of the superior mesenteric artery on abdominal magnetic resonance imaging. A complete pancreatectomy with splenectomy and left-sided adrenalectomy were performed. At this second relapse, this neuroendocrine tumor clinically had changed its hormonal profile. Immunohistochemically, in contrast to primary tumor and first relapse, we found strong immunostaining for ACTH in tumor cells of the second relapse and a MIB-1 index greater than 20%. To our knowledge, this is the first report describing a pancreatic neuroendocrine tumor that started to secrete ACTH de novo at the time of the second relapse after two former complete tumor resections. This case underscores the pluripotency of neuroendocrine tumor cells and the importance of keeping in mind a possible shift in hormone production during tumor evolution and progression.