Papillary craniopharyngioma: a type of tumor primarily impairing the hypothalamus. A comprehensive anatomo-clinical characterization of 350 well-described cases

Objective: Papillary craniopharyngiomas (PCPs) represent a rare histological variant of craniopharyngiomas (CPs) usually involving the hypothalamus. This study systematically analyzes the clinical-anatomical correlation between tumor topography and symptoms related to hypothalamic dysfunction in the largest series of PCPs ever gathered. Methods: From 5,346 CP reports published from 1856 to 2021, we selected 350 well-described cases of the squamous-papillary type. Clinical presentation, tumor topography, severity of hypothalamic adhesion, patient outcome and tumor recurrence were thoroughly analyzed. Results: PCPs predominantly occur in adult (96.3%), male (61.7%) patients presenting with headache (63.4%), visual alterations (56.2%) and psychiatric disturbances (50.4%). Most PCPs are solid (50%), round (50%) lesions that occupy the third ventricle (3V, 94.8%) and show low-risk severity adhesions to the hypothalamus (66.8%). Two major topographical categories can be found: strictly 3V (57.5%), growing above an intact 3V floor (3VF) and not-strictly or infundibulo-tuberal (32.9%), expanding at the infundibulum and/or tuber cinereum. The hypothalamic syndrome predominated among strictly 3V PCPs (p<0.001). Psychiatric symptoms (p<0.001) and high-risk hypothalamic attachments (p=0.031) related to unfavorable postoperative outcomes among patients treated from 2006 onwards. The not-strictly 3V topography was identified as the major predictor of high-risk hypothalamic attachments (71.2% correctly predicted), which, along with incomplete tumor removal (p=0.018), underlies the higher tumor recurrence of this topography (p=0.001). Conclusions: This systematic review evidences that PCP topography is a major determinant of hypothalamic-related symptoms, type of hypothalamic attachments and tumor recurrence rate. Accurate preoperative definition of PCP-hypothalamus relationships is essential for the judicious, safe management of these complex lesions.

GABAB receptor antagonism from birth to weaning permanently modifies Kiss1 expression in hypothalamus and gonads in mice

Introduction: The kisspeptin gene Kiss1 is expressed in two hypothalamic areas: anteroventral periventricular nucleus/periventricular nucleus (AVPV/PeN) and arcuate nucleus (ARC), and also in gonads. Evidences suggest that gamma-amino butyric acid B receptors (GABAB) signaling can regulate Kiss1 expression. Here we inhibited GABAB signaling from PND2-PND21 and evaluated the hypothalamic-pituitary-gonadal (HPG) axis. Methods: BALB/c mice were treated on postnatal days 2-21 (PND2-PND21) with CGP55845 (GABAB antagonist), and evaluated in PND21 and adulthood: gene expression (qPCR) in hypothalamus and gonads, hormones by radioimmunoassay, gonad histochemistry (H&E), puberty onset, estrous cycles. Results: At PND21, CGP inhibited Kiss1 and Tac2 and increased Pdyn and Gabbr1 in the ARC of both sexes and decreased Th only in female AVPV/PeN. Serum follicle-stimulating hormone (FSH) and testis weight decreased in CGP-males and puberty onset was delayed. In adults, Kiss1, Tac2, Pdyn, Pgr, Cyp19a1, Gad1 were downregulated, while Gabbr1 was upregulated in the ARC of both sexes. In the AVPV/PeN, Kiss1, Th, Cyp19a1 and Pgr decreased while Gad1 increased in CGP-females, whereas Cyp19a1 increased in CGP-males. Serum FSH increased in CGP-males while prolactin increased in CGP-females. Testosterone and progesterone increased in ovaries from CGP-females, in which Kiss1, Cyp19a1 and Esr1 were downregulated while Hsd3b2 was upregulated, together with increased atretic and decreased ovulatory follicles. Testes from CGP-males showed decreased progesterone, increased Gabbr1, Kiss1, Kiss1r, Esr2 and decreased Cyp19a1 and clear signs of seminiferous tubules atrophy. Conclusion: These results demonstrate that appropriate GABAB signaling during this critical prepubertal period is necessary for the normal development of the HPG axis.

Associations between prolactin, diabetes and cognitive impairment: a literature review

Background: Converging evidence indicates prolactin (PRL) and diabetes play an important role in the pathophysiology of cognitive impairment. However, little is known about the mechanisms responsible for the effects of PRL and diabetes on cognitive impairment. Summary: We summarize and review the available literature and current knowledge of the association between PRL and diabetes on aspects of cognitive impairment. Key Messages: The PI3K/AKT pathway is central to the molecular mechanisms underlying how PRL and diabetes interact in cognitive impairment. Further work is needed to identify the interaction between PRL and diabetes, especially in the molecular aspects of cognitive impairment, which can suggest novel strategies for cognitive dysfunction treatment.

High Mast Cell Density Predicts a Favorable Prognosis in Patients with Pancreatic Neuroendocrine Neoplasms

Introduction: Mast cells are involved in allergic diseases, immune regulation, and tumor microenvironment modulation, with both pro- and anti-tumorigenic functions, and could serve as a prognostic factor in various cancers. However, their potential role in pancreatic neuroendocrine neoplasms (PanNENs) is largely unknown. Here, our aim was to investigate the presence of mast cells in PanNENs and evaluate their association with clinicopathological parameters and other common tumor-infiltrating immune cells. Methods: Tissue microarrays containing PanNEN samples from 187 patients were constructed and stained immunohistochemically for CD117, CD15, CD68, CD3, CD4, and CD8. Immune cells were counted from four high-power fields (HPFs; 400×) at maximal concentrations, and the mean counts were calculated per HPF. The cut-off values were set by X-tile. Results: The median (interquartile range) counts of CD117+ mast cells, CD15+ neutrophils, CD68+ macrophages, CD3+ T cells, and CD4+ T cells were 3.5 (2.0–6.0), 3.0 (1.3–6), 3.8 (2.5–5.8), 13 (8.0–24.0), 2.0 (1.0–4.0)/HPF, respectively. CD8+ T cells were not detected. The cut-off values for these immune cells were 1.5/HPF, 6/HPF, 4.8/HPF, 32.5/HPF, and 2/HPF, respectively. Low mast cell density was correlated with higher grades, non-insulinoma, and advanced stages. Moreover, high mast cell infiltration was associated with elevated CD4+ T cell and CD15+ neutrophil counts. Multivariate analysis revealed that high mast cell density was an independent predictor of prolonged progression-free survival in the entire cohort, in pancreatic neuroendocrine tumors, and in intermediate-grade, non-insulinoma, and advanced stage subgroups. Conclusions: These findings suggest a protective role of mast cells in PanNENs.

Thyroid disorders and development of cognitive impairment: a review study

Dementia is a neurological disorder that is spreading with increasing human lifespan. In this neurological disorder, memory and cognition are declined and eventually impaired. Various factors can be considered as the background of this disorder, one of which is endocrine disorders. Thyroid hormones are involved in various physiological processes in the body; one of the most important of them is neuromodulation. Thyroid disorders, including hyperthyroidism or hypothyroidism, can affect the nervous system and play a role in the development of dementia. Despite decades of investigation, the nature of the association between thyroid disorders and cognition remains a mystery. Given the enhancing global burden of dementia, the principal purpose of this study was to elucidate the association between thyroid disturbances as a potentially modifiable risk factor of cognitive dysfunction. In this review study, we have tried to collect almost all of the reported mechanisms demonstrating the role of hypothyroidism and hyperthyroidism in the pathogenesis of dementia.

Chronic glucocorticoids consumption triggers and worsens experimental Alzheimer’s disease-like pathology by detrimental immune-modulations

Introduction: Among the risk factors identified in the sporadic forms of Alzheimer’s disease (AD), environmental and lifestyle elements are of growing interest. Clinical observations suggest that stressful events can anticipate AD onset, while stress-related disorders can promote AD. Here, we tested the hypothesis that a chronic treatment with glucocorticoids, is sufficient to trigger or exacerbate AD molecular hallmarks. Methods: We first validated a rat model of experimental chronic glucocorticoids consumption (corticosterone in drinking water for 4 weeks). Then, to evaluate the consequences of chronic glucocorticoids consumption on the onset of amyloid-β (Aβ) toxicity, animals chronically treated with glucocorticoids were intracerebroventricularly injected with an oligomeric solution of Aβ25-35 (oAβ) (acute model of AD). We evaluated AD-related cognitive deficits and pathogenic mechanisms, with a special emphasis on neuroinflammatory markers. Results: Chronic corticosterone consumption caused the inhibition of the non-amyloidogenic pathways, the impairment of Aβ clearance processes and the induction of amyloidogenic pathways in the hippocampus. The principal enzymes involved in glucocorticoid receptor (GR) activation and Tau phosphorylation were upregulated. Importantly, the AD-like phenotype triggered by chronic corticosterone was analogous to the one caused by oAβ. These molecular commonalities across models were independent from inflammation, as chronic corticosterone was immunosuppressive while oAβ was pro-inflammatory. When chronic corticosterone consumption anticipated the induction of the oAβ pathology, we found a potentiation of neuroinflammatory processes associated with an exacerbation of synaptic and memory deficits but also an aggravation of AD-related hallmarks. Discussion/Conclusion: This study unravels new functional outcomes identifying chronic corticosterone consumption as a main risk factor for AD and suggests that glucocorticoid-based therapies should be prescribed with caution in populations with AD risk.

GNRH1 Variants in Congenital Hypogonadotropic Hypogonadism: Single-center experience and Systematic Literature Review

Objective: As GNRH1 genotype-phenotype correlation in CHH is not well-studied, we aim to describe the GNRH1 variants in our CHH cohort and present a systematic review as well as genotype-phenotype analysis of all mutation-positive cases reported in the world literature. Design: Retrospective study of GNRH1 mutation-positive patients from a western-Indian center. PRISMA guidelines-based PubMed search of published literature of all GNRH1 mutation-positive patients Setting: Academic medical center. Patient(s): Two probands from our cohort and 19 probands from the world literature. Intervention(s): None Main Outcome Measure(s): Demographic details, clinical presentation, biochemistry, imaging, treatment details, and genotypic data were recorded. Result(s): Two probands in our cohort carried two novel pathogenic biallelic GnRH variants (p.Glu24Leu, c.238-2A>G). Both had a severe reproductive phenotype. We report successful gonadotropin therapy and fertility in one proband. We included 19 probands from 12 studies after the literature review. Ten CHH probands (inclusive two from this study) with biallelic GNRH1 variants had severe reproductive phenotype, low gonadotropins levels, low/normal prolactin, normal pituitary imaging, and no extra-reproductive phenotype. Of seven biallelic variants reported, three were frameshift, two were splice-site and two were missense mutations. All of them were pathogenic/likely pathogenic without oligogenicity. Of seven monoallelic GNRH1 variants reported in eleven probands, four had non-reproductive phenotype, three were Benign/Likely Benign, four were oligogenic. Conclusion(s): GNRH1 biallelic variants lead to severe reproductive phenotype, with low gonadotropin levels without non-reproductive features or oligogenicity. However, the role of GNRH1 monoallelic variants in CHH pathophysiology for reported variants remains questionable.

Expression of Insulin-like Growth Factor Type 1 Receptor is Linked to Inflammation in Adamantinomatous Craniopharyngioma

Introduction Insulin-like growth factor type 1 receptor (IGF1R) is overexpressed in various malignant tumors, which relates to their transformation and recurrence. Craniopharyngioma is a benign tumor with malignant results, often accompanied by a severe inflammatory reaction. However, the relationship between IGF1R expression and the inflammatory response of craniopharyngioma is unclear. Methods We enrolled 85 patients with adamantinomatous craniopharyngioma (ACP) in a study to explore the relationship between IGF1R expression and clinical features of this disease. Results Patients in the IGF1R high expression group had a significantly higher incidence of hypopituitarism, higher recurrence rate and lower progression-free survival. Beta-catenin can further regulate expression of the stem cell marker, CD44, by regulating IGF1R. Using immunofluorescence, we found that tumor stem cell–like cells did not express phosphorylated (p)-ERK, although p-ERK activation was evident in the surrounding cells. Picropodophyllin, a specific inhibitor of IGF1R, increased the expression of p-ERK protein, and decreased the transcription level of interleukin-6. Conclusions High expression of IGF1R might promote inflammation of ACP, which might be an unfavorable factor for pituitary function and prognosis. The high expression of IGF1R in tumor cell stem-like cells might inhibit the expression of p-ERK and promote the generation of inflammatory factors. Insulin-like growth factor type 1 receptor plays a stemness maintenance role in ACP and regulates the production of inflammatory factors through a p-ERK pathway, which suggests that targeting IGF1R and p-ERK might provide a new direction for alleviating tumor inflammation.

Advanced imaging approaches to reveal molecular mechanisms governing neuroendocrine secretion

Identification of the molecular mechanisms governing neuroendocrine secretion and resulting intercellular communication is one of the great challenges of cell biology to better understand organism physiology and neurosecretion disruption-related pathologies such as hypertension, neurodegenerative or metabolic diseases. To visualize molecule distribution and dynamics below the diffraction limit, many imaging approaches have been developed and are still emerging. In this review, we provide an overview of the pioneering studies that use transmission electron microscopy, atomic force microscopy, total internal reflection microscopy and super-resolution microscopy in neuroendocrine cells to visualize molecular mechanisms driving neurosecretion processes, including exocytosis and associated fusion pores, endocytosis and associated recycling vesicles, and protein-protein/protein-lipid interactions. Furthermore, the potential and the challenges of these different advanced imaging approaches for application in the study of neuroendocrine cell biology are discussed, aiming to guide researchers to select the best approach for their specific purpose around the crucial but not yet fully understood neurosecretion process.

Vasopressin resets the central circadian clock in a manner influenced by sex and vasoactive intestinal polypeptide signaling

Circadian rhythms in behavior and physiology are programmed by the suprachiasmatic nucleus (SCN) of the hypothalamus. A subset of SCN neurons produce the neuropeptide arginine vasopressin (AVP), but it remains unclear whether AVP signaling influences the SCN clock directly. Here we test that AVP signaling acting through V1A and V1B receptors influences molecular rhythms in SCN neurons. V1 receptor agonists were applied ex vivo to PERIOD2::LUCIFERASE SCN slices, allowing for real-time monitoring of changes in molecular clock function. V1A/B agonists reset the phase of the SCN molecular clock in a time-dependent manner, with larger magnitude responses by the female SCN. Further, we find evidence that both Gq and Gs signaling pathways interact with V1A/B-induced SCN resetting, and that this response requires vasoactive intestinal polypeptide (VIP) signaling. Collectively, this work indicates that AVP signaling resets SCN molecular rhythms in conjunction with VIP signaling and in a manner influenced by sex. This highlights the utility of studying clock function in both sexes and suggests that signal integration in central clock circuits regulates emergent properties important for the control of daily rhythms in behavior and physiology.