OBJECTIVE: To establish an cell model of hyperparathyroidism by isolation, in vitro culture, and identification of parathyroid cells from patients with secondary hyperparathyroidism (SHPT). METHODS: The parathyroid gland tissues obtained from 10 patients with SHPT were dissociated by collagenase digestion for primary culture of the parathyroid cells. Morphological changes and growth characteristics of the cells were assessed by microscopic imaging and cell counting. The mRNA and protein expression levels of parathyroid hormone (PTH), calcium-sensing receptor (CaSR), and glial cells missing 2 (GCM2) in the primary and passaged cells were determined by immunofluorescence, qRT-PCR, and Western blotting. RESULTS: Primary cultures of parathyroid cells were successfully obtained. The cells exhibited a high expression of PTH shown by immunofluorescence assay and had a population doubling time of approximately 71.61 h. PTH secretion in the second-passage (P2) cells was significantly lower than that in the primary (P0) and first-passage (P1) cells (P < 0.001). Despite a significant downregulation of CaSR mRNA (P=0.017) and protein (P=0.006) in P1 cells as compared with P0 cells, no significant differences were found in mRNA and protein expressions of PTH or GCM2 between the two cell generations. CONCLUSION Primary cultures of parathyroid cells isolated from SHPT patients by collagenase digestion show similar biological properties to the cells in vivo.
Humans ; Hyperparathyroidism, Secondary/metabolism* ; Parathyroid Glands/metabolism* ; Parathyroid Hormone ; RNA, Messenger/metabolism* ; Receptors, Calcium-Sensing/metabolism*

OBJECTIVE: To explore the genetic basis for a child featuring idiopathic epilepsy and autism. METHODS: Peripheral blood samples of the child and his parents were collected with informed consent for the extraction of genome DNA. Whole exome sequencing was carried out for the family trio. Candidate variants were verified by Sanger sequencing and bioinformatic analysis. RESULTS: The proband was found to harbor a heterozygous nonsense c.3025C>T (p.Arg1009Ter) variant in exon 7 of the CASR gene exon 7, which may produce a truncated protein. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be deleterious and classified as possibly pathogenic (PVS1+PM2). CONCLUSION The c.3025C>T (p.Arg1009Ter) variant of the CASR gene probably underlay the disease in this child.
Autistic Disorder ; Child ; Epilepsy/genetics* ; Exons ; Heterozygote ; Humans ; Receptors, Calcium-Sensing/genetics* ; Whole Exome Sequencing

Animals ; Apoptosis ; Endotoxins/toxicity* ; Heart/drug effects* ; MAP Kinase Signaling System ; Myocardium/pathology* ; Rats ; Rats, Wistar ; Receptors, Calcium-Sensing/metabolism*

The study was designed to investigate the effects and mechanism of a calcium-sensing receptor (CaSR) polymorphism at E942K on the proliferation of gastric cancer cells. Single nucleotide polymorphisms (SNPs) were detected between gastric cancers group and normal controls group by DNA sequence analysis. The cell model was constructed by transfection of E942K mutant plasmid and wild-type (WT) plasmid into SGC-7901 and HEK-293 cells. The effect of E942K mutation on cell proliferation ability was detected by CCK8 and cell clone formation experiments. The effect of E942K mutation on calcium signaling was detected by calcium imaging. Western blot experiments were used to detect changes in phosphorylation levels of key proteins ERK1/2 and β-catenin in downstream signaling pathways after E942K mutation. The results showed that the mutation rate of E942K in gastric cancer group was significantly higher than that in normal control group (P < 0.05). CCK8 and cell clone formation experiments showed that E942K mutation significantly improved the proliferation ability of SGC-7901 gastric cancer cells and HEK-293 cells. E942K mutation enhanced calcium signaling in SGC-7901 and HEK-293 cells. E942K mutation enhanced ERK1/2 phosphorylation without affecting β-catenin phosphorylation. The results suggest that E942K mutation in CaSR may ultimately promote the proliferation of gastric cancer cells by enhancing intracellular calcium signaling and ERK1/2 phosphorylation. These results have potential clinical implications for the diagnosis and targeted therapy of gastric cancer.
Calcium ; Cell Proliferation ; HEK293 Cells ; Humans ; MAP Kinase Signaling System ; Mutation ; Receptors, Calcium-Sensing ; genetics ; Stomach Neoplasms ; genetics

OBJECTIVE: To explore the genetic basis for a child with neonatal severe hyperparathyroidism. METHODS: Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Whole exome sequencing was carried out to screen potential mutations. Suspected mutation was verified by Sanger sequencing. RESULTS: The proband was found to carry compound heterozygous variants c.179G>A (p.Cys60Tyr) and c.1525G>A (p.Gly509Arg) of the CaSR gene. The c.179G>A variant was derived from her mother and was unreported previously. The c.1525G>A variant was derived from her father and known to be pathogenic. CONCLUSION The compound heterozygous variants of c.179G>A and c.1525G>A of the CaSR gene probably underlie the disease in the patient. The results of genetic testing has enabled diagnosis and genetic counseling for her family.
Female ; Genetic Counseling ; Genetic Testing ; Humans ; Hyperparathyroidism/genetics* ; Infant, Newborn ; Infant, Newborn, Diseases/genetics* ; Mutation ; Pedigree ; Receptors, Calcium-Sensing/genetics* ; Whole Exome Sequencing

OBJECTIVE: To study the effect of calcium-sensitive receptors (CaSR) on the expression of endothelial nitric oxide synthase (eNOS) and the concentration of nitric oxide (NO) in a neonatal mouse model of persistent pulmonary hypertension (PPH). METHODS: Eighty neonatal C57BL/6 mice were randomly divided into control, PPH, agonist and antagonist groups. The control group was exposed to air, and the other three groups were exposed to 12% oxygen. The agonist and antagonist groups were intraperitoneally injected with a CaSR agonist (GdCl 16 mg/kg) and a CaSR antagonist (NPS2390, 1 mg/kg), respectively, while the PPH and control groups were intraperitoneally injected with normal saline instead. All mice were treated for 14 days. Alveolar development and pulmonary vessels were assessed by hematoxylin-eosin staining. The protein and mRNA expression of eNOS and its localization in lung tissues were determined by Western blot, qRT-PCR and immunohistochemistry. The levels of brain natriuretic peptide (BNP) and NO in lung homogenate were determined using ELISA. RESULTS: Compared with the control group, the PPH and agonist groups showed significant increases in alveolar mean linear intercept, the percent wall thickness of pulmonary arterioles, right to left ventricular wall thickness ratio (RV/LV) and BNP concentration, but a significant reduction in radial alveolar count (P<0.05). The antagonist group had significant improvements in all the above indices except RV/LV compared with the PPH and agonist groups (P<0.05). Compared with those in the control group, the protein and mRNA expression of eNOS and NO concentration were significantly increased in the PPH group and increased more significantly in the agonist group, but were significantly reduced in the antagonist group (P<0.05). CONCLUSIONS CaSR plays an important role in the development of PPH in neonatal mice, possibly by increasing eNOS expression and NO concentration.
Animals ; Animals, Newborn ; Calcium ; Hypertension, Pulmonary ; Hypoxia ; Mice ; Mice, Inbred C57BL ; Nitric Oxide ; Nitric Oxide Synthase Type III ; Receptors, Calcium-Sensing

OBJECTIVE: To investigate the effects of calcium-sensitive receptors (CaSR) on the expression of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) and cortisol concentration in a neonatal mouse model of persistent pulmonary hypertension (PPH). METHODS: Fifty-six newborn C57BL/6 mice were randomly divided into a control group (n=14), a PPH group (n=14), an agonist group (n=14), and an inhibitor group (n=14). The mice in the PPH, agonist, and inhibitor groups were exposed to a 12% oxygen concentration, and the agonist group and inhibitor group were given CaSR agonist (GdCl3, 16 mg/kg) and CaSR antagonist (NPS2390, 1 mg/kg) intraperitoneally once a day, respectively. The mice in control group were exposed to air, and then injected with an equal volume of normal saline as those in the PPH group every day. All mice were treated for 14 days. Morphological examination of heart and lung tissues was performed using hematoxylin-eosin staining. The expression levels of 11β-HSD2 mRNA and 11β-HSD2 protein in lung tissues were measured by qRT-PCR and Western blot respectively. Brain natriuretic peptide (BNP) and cortisol levels in lung tissues were determined using ELISA. RESULTS: Compared with the control group, the PPH group had significantly increased pulmonary artery wall thickness (WT%), ratio of right to left ventricular thickness (RV/LV), alveolar mean linear intercept, and BNP concentration and a significantly reduced radial alveolar count (P<0.05); compared with the PPH group, the agonist group showed significant increases in WT% and BNP concentration, while the inhibitor group showed significant reductions in the two indicators (P<0.05). Compared with the control group, the PPH group showed significant reductions in the expression levels of 11β-HSD2 mRNA and 11β-HSD2 protein, but a significant increase in cortisol concentration (P<0.05); compared with the PPH group, the agonist group had significantly lower expression levels of 11β-HSD2 mRNA and 11β-HSD2 protein, but a significant higher cortisol concentration, while the inhibitor group showed opposite changes in these indicators (P<0.05). CONCLUSIONS CaSR may control the development and progression of PPH in newborn mice by regulating the expression of 11β-HSD2 and cortisol concentration.
11-beta-Hydroxysteroid Dehydrogenase Type 2 ; Animals ; Animals, Newborn ; Calcium ; Hydrocortisone ; Hypertension, Pulmonary ; Mice ; Mice, Inbred C57BL ; Receptors, Calcium-Sensing

OBJECTIVE: To investigate the change of calcium sensing receptor (CaSR) expression at different time in rat tissue with acute myocardial infarction (AMI) and its effect on cardiomyocyte apoptosis. METHODS: The healthy Wistar rats were randomly divided into Sham and AMI groups, the rat myocardial infarction model was established by ligating left anterior descending coronary artery. The changes of cardiac morphology and hemodynamics were detected at 1, 2 and 4 weeks,respectively. The expressions of CaSR mRNA and protein in myocardial tissue were detected by RT-PCR and Western blot, respectively. The expressions of Bax, Bcl-2, caspase-3 and caspase-9 proteins were detected by Western blot. The serum levels of lactate dehydrogenase (LDH), creatine kinase (CK) activity and cardiac troponin (cTnT) were determined. The apoptosis of cardiomyocytes were tested by TUNEL staining. RESULTS: Compared with the sham group, the expressions of CaSR mRNA and protein, the apoptosis index were increased significantly with the development of AMI (P＜0.05). The ultrastructural damage of cardiomyocytes was serious; the levels of LVSP, +dp/dt and -dp/dt were decreased,while the levels of LVEDP was increased (P＜0.05); In AMI group, the cTnT level, CK and LDH activities were all increased (P＜0.05). With the development of myocardial infarction, the cTnT level and CK activity were gradually decreased, while the activity of LDH was not significantly changed. The expressions of promote apoptosis-related Bax, caspase-3 and caspase-9 were significantly increased, and the expression of inhibited apoptosis-related protein(factor)Bcl-2 was significantly decreased (P＜0.05). CONCLUSION With the development of myocardial infarction,the expressions of CaSR mRNA and protein,the apoptosis index in rat myocardial tissue were increased with time prolongation after AMI. The increased expression of CaSR is involved in rat myocardial infarction, which is related with apoptosis.
Animals ; Apoptosis ; Myocardial Infarction ; metabolism ; Myocardium ; metabolism ; Random Allocation ; Rats ; Rats, Wistar ; Receptors, Calcium-Sensing ; metabolism

The retinal degeneration resulting from elevated intraocular pressure was evaluated through functional and morphological analyses, for better understanding of the pathophysiology of glaucoma. Ocular hypertension was induced via unilateral episcleral venous cauterization in rats. Experimental time was set at 1 and 3 days, and 1, 2, 4, and 8 weeks post-operation. Retinal function was analyzed using electroretinography. For morphological analysis, retinal tissues were processed for immunochemistry by using antibodies against the calcium-sensing receptor and calcium-binding proteins. Apoptosis was analyzed using the TUNEL method and electron microscopy. Amplitudes of a- and b-wave in scotopic and photopic responses were found to be reduced in all glaucomatous retinas. Photopic negative response for ganglion cell function significantly reduced from 1-day and more significantly reduced in 2-week glaucoma. Calcium-sensing receptor immunoreactivity in ganglion cells remarkably reduced at 8 weeks; conversely, protein amounts increased significantly. Calcium-binding proteins immunoreactivity in amacrine cells clearly reduced at 8 weeks, despite of uneven changes in protein amounts. Apoptosis appeared in both photoreceptors and ganglion cells in 8-week glaucomatous retina. Apoptotic feature of photoreceptors was typical, whereas that of ganglion cells was necrotic in nature. These findings suggest that elevated intraocular pressure affects the sensitivity of photoreceptors and retinal ganglion cells, and leads to apoptotic death. The calcium-sensing receptor may be a useful detector for alteration of extracellular calcium levels surrounding the ganglion cells.
Amacrine Cells ; Animals ; Antibodies ; Apoptosis ; Calcium ; Calcium-Binding Proteins ; Cautery ; Electroretinography ; Ganglion Cysts ; Glaucoma ; Immunochemistry ; In Situ Nick-End Labeling ; Intraocular Pressure ; Methods ; Microscopy, Electron ; Ocular Hypertension ; Rats ; Receptors, Calcium-Sensing ; Retina ; Retinal Degeneration ; Retinal Ganglion Cells ; Retinaldehyde

Autosomal-dominant hypocalcemia with hypercalciuria (ADHH) is a genetic disease characterized by hypoparathyroidism with hypercalciuria. Most patients with ADHH have calcium-sensing receptor (CaSR) gene mutations. The CaSR gene controls parathyroid secretions, and mutations in this gene can be detected via changes in serum calcium level. The activating mutation of the CaSR gene results in familial or sporadic ADHH. Most activating mutations of the CaSR gene are reportedly de novo missense mutations. This is the first case report of a novel activating variant of the CaSR gene in a neonate with congenital hypoparathyroidism with hypomagnesemia and hypercalciuria. We also report the 3-month follow-up management of the patient.
Calcium ; Follow-Up Studies ; Humans ; Hypercalciuria ; Hypocalcemia ; Hypoparathyroidism* ; Infant, Newborn* ; Mutation, Missense ; Receptors, Calcium-Sensing