Hyperplasia in glands with hormone excess

Identification of Circular RNAs in Hypothalamus of Gilts during the Onset of Puberty

The disorders of puberty have shown negative outcomes on health of mammals, and the hypothalamus is thought to be the main regulator of puberty by releasing GnRH. Many studies show that the circular RNAs (circRNAs) might be implicated in the timing of puberty in mammals. However, the circRNAs in the hypothalamus of gilts have not been explored. To profile the changes and biological functions of circRNAs in the hypothalamus during the onset of puberty, RNA-seq was utilized to establish pre-, in-, and post-pubertal hypothalamic circRNAs profiles. In this study, the functions of hypothalamic circRNAs were enriched in the signaling pathway of neurotrophin, progesterone-mediated oocyte maturation, oocyte meiosis, insulin, ErbB, and mTOR, which have been highly suggested to be involved in the timing of puberty. Furthermore, 53 circRNAs were identified to be putative hypothalamus-specific expressed circRNAs, and some of them were exclusively expressed in the one of three pubertal stages. Moreover, 22 differentially expressed circRNAs were identified and chosen to construct the circRNA-miRNA-gene network. Moreover, 10 circRNAs were found to be driven by six puberty-related genes (ESR1, NF1, APP, ENPP2, ARNT, and DICER1). Subsequently, the expression changes of several circRNAs were confirmed by RT-qPCR. Collectively, the preliminary results of hypothalamic circRNAs provided useful information for the investigation of the molecular mechanism for the timing of puberty in gilts.

Symptomatic primary hyperparathyroidism in a young woman presenting with multiple skeletal destructions: a case report and review of literature

BACKGROUND

Multiple pathological manifestations are rarely present in patients with primary hyperparathyroidism (PHPT). Here we described a case of a young woman who presented with multiple skeletal destructions and received an unclear diagnosis at several hospitals.

CASE PRESENTATION

A 30-year-old woman was admitted to our hospital due to pain in both knees and walking difficulty that lasted for 6 and 2 years, respectively. Her laboratory test results revealed a high parathyroid hormone level (822 pg/ml) and hypercalcemia (2.52 mmol/L) in the blood. Parathyroid imaging revealed a lumpy concentration of radioactive uptake detected at the lower pole in the right lobe of the thyroid, and was nearly 2.2 cm * 2.4 cm in size. Next, the patient was treated with parathyroidectomy that resulted in a significant improvement in physiological and clinical symptoms. Moreover, the skeletal destruction and bone mineral density were significantly improved after a 5-years follow-up period.

CONCLUSIONS

Multiple skeletal destructions can be caused by PHPT that should be taken into consideration in young patients with complex bone lesions.

Cinacalcet corrects biased allosteric modulation of CaSR by AHH autoantibody

Biased agonism is a paradigm that may explain the selective activation of a signaling pathway via a GPCR that activates multiple signals. The autoantibody-induced inactivation of the calcium-sensing receptor (CaSR) causes acquired hypocalciuric hypercalcemia (AHH). Here, we describe an instructive case of AHH in which severe hypercalcemia was accompanied by an increased CaSR antibody titer. These autoantibodies operated as biased allosteric modulators of CaSR by targeting its Venus flytrap domain near the Ca2+-binding site. A positive allosteric modulator of CaSR, cinacalcet, which targets its transmembrane domain, overcame this autoantibody effect and successfully corrected the hypercalcemia in this patient. Hence, this is the first study to our knowledge that identifies the interaction site of a disease-causing GPCR autoantibody working as its biased allosteric modulator and demonstrates that cinacalcet can correct the AHH autoantibody effects both in vitro and in our AHH patient. Our observations provide potentially new insights into how biased agonism works and how to design a biased allosteric modulator of a GPCR. Our observations also indicate that the diagnosis of AHH is important because the severity of hypercalcemia may become fatal if the autoantibody titer increases. Calcimimetics may serve as good treatment options for some patients with severe AHH.

Primary hyperparathyroidism characterized by diffuse homogeneous metastatic pulmonary calcification: A case report

RATIONALE

Primary hyperparathyroidism (PHPTI) with respiratory tract symptom is extremely rare. It is caused by autonomic oversecretion of parathyroid hormone (PTH) owing to parathyroid adenoma, hyperplasia, or tumor. The diagnosis of PHPTI often needs to be made based on medical history, clinical manifestation, laboratory tests, and imaging examination. Moreover, no study has reported PHPTI with diffuse metastatic pulmonary calcification (MPC) as the characteristic.

PATIENT CONCERNS

A 49-year-old female from Zhejiang, China, had a fever of unknown origin, cough with white crude sputum, and asthma after activity for 1 month.

DIAGNOSIS

The computed tomography (CT) examination revealed a homogeneous and diffuse high-density shadow in both lungs. The pathologic examination with CT-guided lung biopsy (left lung puncture) suggested interstitial inflammation of the lung tissue, combined with fibroblast proliferation as well as calcification. B-ultrasonography identified a lump in the right parathyroid gland, with a size of 4.1 × 1.7 × 1.9 cm. Color Doppler sonography indicated rich blood flow inside the lump. Whole-body bone emission computed tomography imaging showed the enhancement of bone metabolism in bilateral lower extremities and a diffuse enhancement of radioactive distribution in both lungs. Tc-methoxyisobutyl isonitrile imaging suggested significantly increased MIBI uptake in the right superior pole of the thyroid gland and indicated adenoma of the right superior parathyroid. The diagnosis of PHPTI was confirmed by postoperative pathology.

INTERVENTIONS

The patient received a resection of the right parathyroid adenoma.

OUTCOMES

After surgery, the symptom such as fever, coughing, and white crude sputum were significantly alleviated.

LESSONS

This novel case reported the case of a patient with PHPTI having respiratory tract infection as the 1st symptom and diffuse MPC as the symptom characteristic PHPTI, the findings of this case study might improve the recognition of PHPTI on diffuse pulmonary calcification for clinical doctors.

Gain-of-function mutations in G-protein-coupled receptor genes associated with human endocrine disorders

The human genome encodes more than 700 G-protein-coupled receptors (GPCRs), many of which are involved in hormone secretion. To date, more than 100 gain-of-function (activating) mutations in at least ten genes for GPCRs, in addition to several loss-of-function mutations, have been implicated in human endocrine disorders. Previously reported gain-of-function GPCR mutations comprise various missense substitutions, frameshift mutations, intragenic inframe deletions and copy-number gains. Such mutations appear in both germline and somatic tumour cells, and lead to various hormonal abnormalities reflecting excessive receptor activity. Phenotypic consequences of these mutations include distinctive endocrine syndromes, as well as relatively common hormonal abnormalities. Such mutations encode hyperfunctioning receptors with increased constitutive activity, broadened ligand specificity, increased ligand sensitivity and/or delayed receptor desensitization. Furthermore, recent studies proposed a paradoxical gain-of-function mechanism caused by inactive GPCR mutants. Molecular diagnosis of GPCR activating mutations serves to improve the clinical management of mutation-positive patients. This review aims to introduce new aspects regarding gain-of-function mutations in GPCR genes associated with endocrine disorders.

Diseases associated with calcium-sensing receptor

The calcium-sensing receptor (CaSR) plays a pivotal role in systemic calcium metabolism by regulating parathyroid hormone secretion and urinary calcium excretion. The diseases caused by an abnormality of the CaSR are genetically determined or are more rarely acquired. The genetic diseases consist of hyper- or hypocalcemia disorders. Hypercalcaemia disorders are related to inactivating mutations of the CASR gene either heterozygous (autosomal dominant familial benign hypercalcaemia, still named hypocalciuric hypercalcaemia syndrome type 1) or homozygous (severe neonatal hyperparathyroidism). The A986S, R990G and Q1011E variants of the CASR gene are associated with higher serum calcium levels than in the general population, hypercalciuria being also associated with the R990G variant. The differential diagnosis consists in the hypocalciuric hypercalcaemia syndrome, types 2 (involving GNA11 gene) and 3 (involving AP2S1 gene); hyperparathyroidism; abnormalities of vitamin D metabolism, involving CYP24A1 and SLC34A1 genes; and reduced GFR. Hypocalcemia disorders, which are more rare, are related to heterozygous activating mutations of the CASR gene (type 1), consisting of autosomal dominant hypocalcemia disorders, sometimes with a presentation of pseudo-Bartter’s syndrome. The differential diagnosis consists of the hypercalciuric hypocalcaemia syndrome type 2, involving GNA11 gene and other hypoparathyroidism aetiologies. The acquired diseases are related to the presence of anti-CaSR antibodies, which can cause hyper- or especially hypocalcemia disorders (for instance in APECED syndromes), determined by their functionality. Finally, the role of CaSR in digestive, respiratory, cardiovascular and neoplastic diseases is gradually coming to light, providing new therapeutic possibilities. Two types of CaSR modulators are known: CaSR agonists (or activators, still named calcimimetics) and calcilytic antagonists (or inhibitors of the CasR). CaSR agonists, such as cinacalcet, are indicated in secondary and primary hyperparathyroidism. Calcilytics have no efficacy in osteoporosis, but could be useful in the treatment of hypercalciuric hypocalcaemia syndromes.