Steroid hormones play a crucial role in supporting a successful pregnancy and ensuring proper fetal development. The placenta is one of the principal tissues in steroid production and metabolism, expressing a vast range of steroidogenic enzymes. Nevertheless, a comprehensive characterization of steroidogenic pathways in the human placenta and potential developmental changes occurring during gestation are poorly understood. Furthermore, the specific contribution of trophoblast cells in steroid release is largely unknown. Thus, this study aimed to (i) identify gestational age-dependent changes in the gene expression of key steroidogenic enzymes and (ii) explore the role of trophoblast cells in steroid biosynthesis and metabolism. Quantitative and Droplet Digital PCR analysis of 12 selected enzymes was carried out in the first trimester (n = 13) and term (n = 20) human placentas. Primary trophoblast cells (n = 5) isolated from human term placentas and choriocarcinoma-derived cell lines (BeWo, BeWo b30 clone, and JEG-3) were further screened for gene expression of enzymes involved in placental synthesis/metabolism of steroids. Finally, de novo steroid synthesis by primary human trophoblasts was evaluated, highlighting the functional activity of steroidogenic enzymes in these cells. Collectively, we provide insights into the expression patterns of steroidogenic enzymes as a function of gestational age and delineate the cellular origin of steroidogenesis in the human placenta.

• MeSH
• choriokarcinom metabolismus   patologie   MeSH
• dospělí MeSH
• gestační stáří MeSH
• kultivované buňky MeSH
• lidé MeSH
• novorozenec MeSH
• placenta cytologie   metabolismus   MeSH
• první trimestr těhotenství metabolismus   MeSH
• regulace genové exprese * MeSH
• steroidhydroxylasy genetika   metabolismus   MeSH
• steroidy metabolismus   MeSH
• těhotenství MeSH
• trofoblasty cytologie   metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• novorozenec MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

• Klíčová slova
• idiopatická infantilní hyperkalcémie,
• MeSH
• biologické markery MeSH
• CYP24A1 MeSH
• genetické testování * metody   využití   MeSH
• hyperkalcemie * diagnóza   etiologie   terapie   MeSH
• klinický obraz nemoci * MeSH
• kojenec MeSH
• lidé MeSH
• mutace genetika   účinky léků   MeSH
• statistika jako téma MeSH
• steroidhydroxylasy genetika   izolace a purifikace   metabolismus   MeSH
• tekutinová terapie metody   využití   MeSH
• vitamin D genetika   izolace a purifikace   škodlivé účinky   MeSH
• vrozené poruchy metabolismu diagnóza   etiologie   genetika   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

The constitutive androstane receptor(CAR) activation is connected with mitogenic effects leading to liver hyperplasia and tumorigenesis in rodents. CAR activators, including phenobarbital, are considered rodent non-genotoxic carcinogens. Recently, trans-3,4,5,4´-tetramethoxystilbene(TMS), a potential anticancer drug (DMU-212), have been shown to alleviate N-nitrosodiethylamine/phenobarbital-induced liver carcinogenesis. We studied whether TMS inhibits mouse Car to protect from the PB-induced tumorigenesis. Unexpectedly, we identified TMS as a murine CAR agonist in reporter gene experiments, in mouse hepatocytes, and in C57BL/6 mice in vivo. TMS up-regulated Car target genes Cyp2b10, Cyp2c29 and Cyp2c55 mRNAs, but down-regulated expression of genes involved in gluconeogenesis and lipogenesis. TMS did not change or down-regulate genes involved in liver proliferation or apoptosis such as Mki67, Foxm1, Myc, Mcl1, Pcna, Bcl2, or Mdm2, which were up-regulated by another Car ligand TCPOBOP. TMS did not increase liver weight and had no significant effect on Ki67 and Pcna labeling indices in mouse liver in vivo. In murine hepatic AML12 cells, we confirmed a Car-independent proapoptotic effect of TMS. We conclude that TMS is a Car ligand with limited effects on hepatocyte proliferation, likely due to promoting apoptosis in mouse hepatic cells, while controlling Car target genes involved in xenobiotic and endobiotic metabolism.

• MeSH
• antikarcinogenní látky metabolismus   farmakologie   MeSH
• apoptóza účinky léků   MeSH
• aromatické hydroxylasy genetika   metabolismus   MeSH
• buňky Hep G2 MeSH
• glukoneogeneze účinky léků   genetika   MeSH
• hepatocyty účinky léků   metabolismus   patologie   MeSH
• játra účinky léků   metabolismus   MeSH
• lidé MeSH
• lipogeneze účinky léků   genetika   MeSH
• myši inbrední C57BL MeSH
• nádory jater enzymologie   genetika   patologie   prevence a kontrola   MeSH
• proliferace buněk účinky léků   MeSH
• pyridiny farmakologie   MeSH
• receptory cytoplazmatické a nukleární agonisté   genetika   metabolismus   MeSH
• regulace genové exprese enzymů účinky léků   MeSH
• rodina 2 cytochromů P450 genetika   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• simulace molekulového dockingu MeSH
• steroidhydroxylasy genetika   metabolismus   MeSH
• stilbeny metabolismus   farmakologie   MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• Klíčová slova
• idiopatická infantilní hyperkalcémie,
• MeSH
• biologické markery MeSH
• CYP24A1 MeSH
• genetické testování * metody   využití   MeSH
• hyperkalcemie * diagnóza   etiologie   terapie   MeSH
• klinický obraz nemoci * MeSH
• kojenec MeSH
• lidé MeSH
• mutace genetika   účinky léků   MeSH
• statistika jako téma MeSH
• steroidhydroxylasy genetika   izolace a purifikace   metabolismus   MeSH
• tekutinová terapie metody   využití   MeSH
• vitamin D genetika   izolace a purifikace   škodlivé účinky   MeSH
• vrozené poruchy metabolismu diagnóza   etiologie   genetika   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

Idiopathic infantile hypercalcemia (IIH) is a rare disorder caused by CYP24A1 loss-of-function mutation, resulting in impaired degradation of 1,25-dihydroxyvitamin D3. Pamidronate, an intravenously administered bisphosphonate, which is a potent inhibitor of bone resorption, has been reported only once for treatment IIH. We present a case of a previously healthy 5-month-old boy with IIH, where calcemia peaked to 5 mmol/L. Treatment with methylprednisone and furosemide had only minor effects; therefore, 2 intravenous infusions of pamidronate (0.6 mg/kg per dose) corrected the serum calcium level to 2.95 mmol/L. Furthermore, CYP24A1 homozygous mutation p.R396W (c.1186c>t) was identified in this patient, confirming the clinical diagnosis of IIH. In conclusion, IIH has a favorable outcome once properly detected and appropriately treated. Pamidronate has a beneficial effect in those patients with IIH where glucocorticoids and furosemide fail to meet the expectations.  

• MeSH
• biologické markery metabolismus   MeSH
• bisfosfonáty terapeutické užití   MeSH
• diferenciální diagnóza MeSH
• hyperkalcemie diagnóza   farmakoterapie   genetika   MeSH
• inhibitory kostní resorpce terapeutické užití   MeSH
• kojenec MeSH
• lidé MeSH
• mutace MeSH
• předškolní dítě MeSH
• steroidhydroxylasy genetika   MeSH
• vápník metabolismus   MeSH
• výsledek terapie MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

UNLABELLED: We report on a male infant presenting at 4 months of age with failure to thrive, dehydration, hypotonia, lethargy, and vomiting. Laboratory and imaging tests revealed severe hypercalcemia (5.8 mmol/l), suppressed parathyroid hormone (0.41 pmol/l), hypercalciuria (8.0 mmol/mmol creatinine), elevated 25-hydroxyvitamin D3 (over 600 nmol/l), and nephrocalcinosis. These symptoms are characteristic of idiopathic infantile hypercalcemia (IIH, MIM 143880). Conservative therapy (parenteral rehydration, diuretics, corticosteroids, bisphosphonates, and vitamin D prophylaxis withdrawal) was not able to improve the symptoms and laboratory values, and acute hemodiafiltration was necessary to normalize hypercalcemia. Clinical symptoms resolved rapidly after normalization of serum calcium levels. Molecular genetic testing revealed a homozygous mutation (R396W) in the CYP24A1 gene (MIM 126065) encoding 25-hydroxyvitamin D3 24-hydroxylase, which is the key enzyme responsible for 1,25-dihydroxyvitamin D3 degradation. The CYP24A1 gene mutation leads to the increased sensitivity of the patients to even prophylactic doses of vitamin D and to the development of severe symptomatic hypercalcemia in patients with IIH. CONCLUSION: Our patient is only the thirteenth patient with IIH caused by mutation in the CYP24A1 gene and the first one needing acute hemodiafiltration for severe symptomatic hypercalcemic crisis. In all patients with suspected IIH the DNA analysis for CYP24A1 gene mutations should be performed regardless of the type of vitamin D supplementation and serum levels of vitamin D.

• MeSH
• diferenciální diagnóza MeSH
• hyperkalcemie diagnóza   genetika   MeSH
• kalcifediol genetika   MeSH
• kojenec MeSH
• lidé MeSH
• mutace MeSH
• steroidhydroxylasy genetika   MeSH
• vápník krev   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Valproic acid (VPA) is a wide spread anticonvulsant and mood-stabilizing agent, the use of which is associated with hepatotoxicity, bone marrow suppression and osteomalacia. In the current paper we propose a possible mechanism of VPA-induced osteomalacia involving accelerated catabolism of 1α,25(OH)(2)-vitamin D3 (VD3) due to increased expression of CYP24. We demonstrate that VPA strongly potentiates CYP24 mRNA expression by VD3 in human hepatocytes (HH) and in human embryonic kidney cells (HEK293). By the method of gene reporter assay we found that VPA increases basal and VD3-inducible activity of CYP24 promoter (pCYP24-luc) in human liver adenocarcinoma (HepG2) and in HEK293 cells in dose-dependent manner. In order to delineate the role of inhibitory effects of VPA on histone deacetylase 1 (HDAC1), we compared the effects of VPA with trichostatin A (TSA) on basal and inducible levels of CYP24 mRNA and pCYP24-luc transactivation. Transactivation of CYP24 promoter by VD3 was enhanced in the presence of both TSA and VPA. In contrast, VD3-inducible expression of CYP24 mRNA was enhanced by VPA but not by TSA, implying that HDAC1 inhibition is not the major reason for VPA effects on CYP24. We examined the effects of VPA on mitogen-activated protein kinases as the important transcriptional regulators of VDR. VPA activated extracellular signal-regulated kinase (ERK) but not c-Jun-N-terminal kinase (JNK) and p38 MAPKs. In conclusion, VPA enhances transcriptional activity of VDR and increases expression of CYP24 mRNA in the presence of VD3 in physiological concentrations. The mechanism involves activation of ERK and partly the inhibition of HDAC1.

• MeSH
• antikonvulziva toxicita   MeSH
• cholekalciferol farmakologie   MeSH
• extracelulárním signálem regulované MAP kinasy genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• hepatocyty účinky léků   MeSH
• histondeacetylasa 1 biosyntéza   genetika   MeSH
• kyselina valproová toxicita   MeSH
• lidé MeSH
• luciferasy genetika   MeSH
• messenger RNA biosyntéza   genetika   MeSH
• osteomalacie chemicky indukované   patologie   MeSH
• plazmidy genetika   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• receptory kalcitriolu účinky léků   MeSH
• steroidhydroxylasy biosyntéza   genetika   MeSH
• steroidní receptory účinky léků   MeSH
• transfekce MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• western blotting MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH