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Xie JL, Zhu HY, Dong Y, Sun PP, Qi DD, Luan SX, Zhang Y, Ma HG. Pulsatile gonadotropin-releasing hormone therapy induces spermatogenesis in pituitary stalk interruption syndrome: A case report and review of the literature. World J Clin Cases 2024; 12:4348-4356. [PMID: 39015932 PMCID: PMC11235527 DOI: 10.12998/wjcc.v12.i20.4348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2024] [Revised: 05/18/2024] [Accepted: 06/04/2024] [Indexed: 06/30/2024] Open
Abstract
BACKGROUND Pituitary stalk interruption syndrome (PSIS) is a rare anatomical defect of the pituitary gland falling under the spectrum of holoprosencephaly phenotypes. It is characterized by a deficiency in anterior pituitary hormones, such as growth hormone, gonadotropins, and thyroid hormones. Due to the syndrome's rarity and nonspecific manifestations, there is a lack of standardized treatment strategies. Consequently, early diagnosis through imaging and on-time intervention are crucial for improving patients' outcomes. CASE SUMMARY A 30-year-old man presented with absent secondary sexual characteristics and azoospermia. Laboratory evaluation revealed a deficiency in gonadotropins, while thyroid function was mostly within normal ranges. Magnetic resonance imaging of the pituitary gland showed pituitary stalk agenesis, hypoplasia of the anterior pituitary, and ectopic posterior pituitary, leading to the diagnosis of PSIS. Initially, the patient underwent 6 mo of gonadotropin therapy without significant changes in hormone levels and secondary sexual characteristics. Pulsatile gonadotropin-releasing hormone therapy was then administered, resulting in the detection of sperm in the semen analysis within 3 mo. After 6 mo, routine semen tests showed normal semen quality. The couple faced challenges in conceiving due to abstinence and underwent three cycles of artificial insemination, which was unsuccessful. They also attempted in vitro fertilization, but unfortunately, the woman experienced a miscarriage 10 wk after the embryo transfer. CONCLUSION Early detection, accurate diagnosis, and timely treatment are crucial in improving the quality of life and fertility of PSIS patients.
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Affiliation(s)
- Jin-Long Xie
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Hai-Ying Zhu
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Yang Dong
- Department of Radiology, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Ping-Ping Sun
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Dan-Dan Qi
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Su-Xian Luan
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Yan Zhang
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
| | - Hua-Gang Ma
- The Reproductive Medicine Centre, Weifang People's Hospital, Weifang 261000, Shandong Province, China
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Kałużna M, Budny B, Rabijewski M, Dubiel A, Trofimiuk-Müldner M, Szutkowski K, Piotrowski A, Wrotkowska E, Hubalewska-Dydejczyk A, Ruchała M, Ziemnicka K. Variety of genetic defects in GnRH and hypothalamic-pituitary signaling and development in normosmic patients with IHH. Front Endocrinol (Lausanne) 2024; 15:1396805. [PMID: 39010903 PMCID: PMC11246878 DOI: 10.3389/fendo.2024.1396805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 05/27/2024] [Indexed: 07/17/2024] Open
Abstract
Introduction Normosmic isolated hypogonadotropic hypogonadism (nIHH) is a clinically and genetically heterogeneous disorder. Deleterious variants in over 50 genes have been implicated in the etiology of IHH, which also indicates a possible role of digenicity and oligogenicity. Both classes of genes controlling GnRH neuron migration/development and hypothalamic/pituitary signaling and development are strongly implicated in nIHH pathogenesis. The study aimed to investigate the genetic background of nIHH and further expand the genotype-phenotype correlation. Methods A total of 67 patients with nIHH were enrolled in the study. NGS technology and a 38-gene panel were applied. Results Causative defects regarded as at least one pathogenic/likely pathogenic (P/LP) variant were found in 23 patients (34%). For another 30 individuals, variants of unknown significance (VUS) or benign (B) were evidenced (45%). The most frequently mutated genes presenting P/LP alterations were GNRHR (n = 5), TACR3 (n = 3), and CHD7, FGFR1, NSMF, BMP4, and NROB1 (n = 2 each). Monogenic variants with solid clinical significance (P/LP) were observed in 15% of subjects, whereas oligogenic defects were detected in 19% of patients. Regarding recurrence, 17 novel pathogenic variants affecting 10 genes were identified for 17 patients. The most recurrent pathogenic change was GNRHR:p.Arg139His, detected in four unrelated subjects. Another interesting observation is that P/LP defects were found more often in genes related to hypothalamic-pituitary pathways than those related to GnRH. Conclusions The growing importance of the neuroendocrine pathway and related genes is drawing increasing attention to nIHH. However, the underestimated potential of VUS variants in IHH etiology, particularly those presenting recurrence, should be further elucidated.
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Affiliation(s)
- Małgorzata Kałużna
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Bartłomiej Budny
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Michał Rabijewski
- Department of Reproductive Health, Centre for Postgraduate Medical Education, Warsaw, Poland
| | - Agnieszka Dubiel
- Chair and Department of Endocrinology, Jagiellonian University Medical College, Kraków, Poland
| | | | - Kosma Szutkowski
- NanoBioMedical Centre at Adam Mickiewicz University in Poznan, Poznan, Poland
| | - Adam Piotrowski
- Department of Biomedical Physics at Adam Mickiewicz University in Poznan, Poznan, Poland
| | - Elżbieta Wrotkowska
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Marek Ruchała
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Katarzyna Ziemnicka
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
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Blake C, Widmeyer K, DAquila K, Mochizuki A, Smolarek TA, Pillay-Smiley N, Kim SY. 14q22.3 duplication including OTX2 in a girl with medulloblastoma: A case report with literature review. Am J Med Genet A 2024; 194:e63604. [PMID: 38511879 DOI: 10.1002/ajmg.a.63604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 03/22/2024]
Abstract
Orthodenticle homeobox 2 (OTX2) is a known oncogenic driver of medulloblastoma. Germline duplication of 14q22.3 including OTX2 is a rare condition reported in patients with combined pituitary hormone deficiency, oculo-auriculo-vertebral spectrum, and hemifacial microsomia. There has been one previously published case of a patient carrying a 14q22.3 duplication that included OTX2 with hemifacial microsomia who also developed medulloblastoma. Here, we present a case of a 6-year-old girl with a history of delayed development who was diagnosed with medulloblastoma. Genetic evaluations revealed that she inherited a germline duplication of 14q22.3, which included OTX2. This genetic alteration was passed down from her mother, who also had a history of delayed development. Results from other genetic testing, including exome sequencing, fragile X syndrome, and mtDNA testing, were negative/normal. This is the second report of a 14q22.3 duplication that included OTX2 in a patient with medulloblastoma. Further studies are necessary to establish a clear association.
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Affiliation(s)
- Claire Blake
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Kimmie Widmeyer
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Kristen DAquila
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Aaron Mochizuki
- Cancer and Blood Disease Institute, The Cure Starts Now Foundation Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Teresa A Smolarek
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Natasha Pillay-Smiley
- Cancer and Blood Disease Institute, The Cure Starts Now Foundation Brain Tumor Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Sun Young Kim
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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Alkhammas AH, Al-Thuwaini TM. Association of birth type and LHX4 gene polymorphism with reproductive hormones, growth hormone, and prolactin in Awassi ewes. Mol Biol Rep 2023; 50:3951-3956. [PMID: 36787052 DOI: 10.1007/s11033-023-08285-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 01/17/2023] [Indexed: 02/15/2023]
Abstract
BACKGROUND LIM homeobox transcription factor 4 (LHX4) is a promising candidate gene for mammalian reproductive traits. LHX4 polymorphism has previously been associated with phenotypic traits in goats and cattle. However, there have been no LHX4 gene polymorphisms identified in Awassi sheep. Therefore, this study investigated the effects of the LHX4 polymorphism on reproductive hormones, growth hormones, and prolactin in Awassi ewes. METHODS AND RESULTS A total of 232 ewes between the ages of 3 and 4 years were selected for this study (123 single-progeny ewes and 109 twin-producing ewes). Serum was collected to measure reproductive hormones, growth hormone, and prolactin using ELISA kits made by ELK Biotechnology. Genomic DNA was extracted from sheep blood, genotyped, and sequenced to confirm variations in LHX4 (exon 1, 207 bp). Genotyping revealed three genotypes in 207 bp: AA, AG, and GG. Sequence analysis detected a novel mutation in exon 1: 160 A > G. Statistically, the 160 A > G SNP was significantly associated with the phenotypic traits. Ewes carrying AA genotypes had higher estrogen, progesterone, follicle-stimulating hormones/luteinizing hormones, and growth hormone, and lower prolactin levels (65.63 ± 3.84) (pg/mL), (6.67 ± 0.38) (ng/mL), (22.34 ± 1.27) (ng/mL)/(23.89 ± 2.13) (ng/mL), (1.30 ± 0.05) (ng/mL), and (13.16 ± 0.75) (pg/mL), respectively, compared to AG and GG genotypes in the fourth month of twin-pregnant ewes compared to single-pregnant ewes. CONCLUSION This study suggests that the 160 A > G SNP negatively affects the Awassi sheep's hormone levels. It provides valuable insight into the sheep LHX4 gene, which could be an effective marker in marker-assisted selection.
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Affiliation(s)
- Ahmed H Alkhammas
- Department of Animal Production, College of Agriculture, Al-Qasim Green University, Babil, Iraq.
| | - Tahreer M Al-Thuwaini
- Department of Animal Production, College of Agriculture, Al-Qasim Green University, Babil, Iraq.
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Hassani B, Hashemi-Madani N, Ataee Kachuee M, Khamseh ME. Magnetic resonance imaging characteristics predict pituitary function in non-functional pituitary macro-adenoma undergoing trans-sphenoidal surgery. BMC Med Imaging 2022; 22:60. [PMID: 35365091 PMCID: PMC8976368 DOI: 10.1186/s12880-022-00787-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 03/28/2022] [Indexed: 11/10/2022] Open
Abstract
Introduction Maintaining the pituitary function after surgery is highly important. The aim of this study was to investigate the relationship between preoperative magnetic resonance imaging (MRI) characteristics and pituitary function after surgery of non-functional pituitary macroadenoma. Methods This retrospective study was performed between 2016 and 2018. Preoperative and postoperative MRI imaging data were retrieved from electronic registration system. The relationship between preoperative MRI characteristics and postoperative pituitary function as well as reconstruction of pituitary gland was investigated using regression models. Results Complete data were available for 44 patients. Before surgery, invisible normal tissue was observed in 23 patients (53.5%). Suprasellar extension and cavernous sinus invasion were seen in 36 patients (each one 49.1%). There was a significant reverse relationship between preoperative tumor size and postoperative thyroid stimulating hormone (TSH) (odds ratio (OR): − 0.99 (− 0.18, − 0.003), p = 0.04). In addition, we found a significant positive correlation between prolactin level after surgery and tumor size before surgery, (OR: 5.29 (1.65, 8.92), p = 0006). Moreover, postoperative panhypopituitarism was observed in 25% of patients with complete morphologic reconstitution of pituitary tissue. While the rate was 50% in patients with no or partial morphologic reconstruction of pituitary tissue. Conclusion Preoperative MRI characteristics predict TSH and prolactin level after operation. Furthermore, the adenoma size and volume prior to surgery are the main determinants of normal morphologic reconstruction of pituitary gland.
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Affiliation(s)
- Behrooz Hassani
- Department of Radiology, Firouzgar Clinical Research Development Center(FCRDC), Firouzgar General Hospital, Iran University of Medical Sciences(IUMS), Valadi Street, Valiasr Sq., Tehran, Iran
| | - Nahid Hashemi-Madani
- Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Science (IUMS), Tehran, Iran
| | - Manizhe Ataee Kachuee
- Department of Radiology, Firouzgar Clinical Research Development Center(FCRDC), Firouzgar General Hospital, Iran University of Medical Sciences(IUMS), Valadi Street, Valiasr Sq., Tehran, Iran.
| | - Mohammad E Khamseh
- Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Science (IUMS), Tehran, Iran
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Bando H, Urai S, Kanie K, Sasaki Y, Yamamoto M, Fukuoka H, Iguchi G, Camper SA. Novel genes and variants associated with congenital pituitary hormone deficiency in the era of next-generation sequencing. Front Endocrinol (Lausanne) 2022; 13:1008306. [PMID: 36237189 PMCID: PMC9551393 DOI: 10.3389/fendo.2022.1008306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Accepted: 09/09/2022] [Indexed: 01/07/2023] Open
Abstract
Combined pituitary hormone deficiency (CPHD) is not a rare disorder, with a frequency of approximately 1 case per 4,000 live births. However, in most cases, a genetic diagnosis is not available. Furthermore, the diagnosis is challenging because no clear correlation exists between the pituitary hormones affected and the gene(s) responsible for the disorder. Next-generation sequencing (NGS) has recently been widely used to identify novel genes that cause (or putatively cause) CPHD. This review outlines causative genes for CPHD that have been newly reported in recent years. Moreover, novel variants of known CPHD-related genes (POU1F1 and GH1 genes) that contribute to CPHD through unique mechanisms are also discussed in this review. From a clinical perspective, variants in some of the recently identified causative genes result in extra-pituitary phenotypes. Clinical research on the related symptoms and basic research on pituitary formation may help in inferring the causative gene(s) of CPHD. Future NGS analysis of a large number of CPHD cases may reveal new genes related to pituitary development. Clarifying the causative genes of CPHD may help to understand the process of pituitary development. We hope that future innovations will lead to the identification of genes responsible for CPHD and pituitary development.
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Affiliation(s)
- Hironori Bando
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
- *Correspondence: Hironori Bando,
| | - Shin Urai
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University School of Medicine, Kobe, Japan
| | - Keitaro Kanie
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
| | - Yuriko Sasaki
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University School of Medicine, Kobe, Japan
| | - Masaaki Yamamoto
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
| | - Hidenori Fukuoka
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
| | - Genzo Iguchi
- Division of Diabetes and Endocrinology, Department of Internal Medicine, Kobe University Hospital, Kobe, Japan
- Division of Biosignal Pathophysiology, Kobe University Graduate School of Medicine, Kobe, Japan
- Medical Center for Student Health, Kobe University, Kobe, Japan
| | - Sally A. Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, United States
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Obara-Moszyńska M, Budny B, Kałużna M, Zawadzka K, Jamsheer A, Rohde A, Ruchała M, Ziemnicka K, Niedziela M. CDON gene contributes to pituitary stalk interruption syndrome associated with unilateral facial and abducens nerve palsy. J Appl Genet 2021; 62:621-629. [PMID: 34235642 PMCID: PMC8571149 DOI: 10.1007/s13353-021-00649-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 06/21/2021] [Accepted: 06/28/2021] [Indexed: 11/06/2022]
Abstract
The relationship between congenital defects of the brain and facial anomalies was proven. The Hedgehog signaling pathway plays a fundamental role in normal craniofacial development in humans. Mutations in the sonic hedgehog (SHH) signaling gene CDON have been recently reported in patients with holoprosencephaly and with pituitary stalk interruption syndrome (PSIS). This study’s aim was an elucidation of an 18-year-old patient presenting PSIS, multiple pituitary hormone deficiency, and congenital unilateral facial and abducens nerve palsy. Additionally, bilateral sensorineural hearing loss, dominating at the right site, was diagnosed. From the second year of life, growth deceleration was observed, and from the age of eight, anterior pituitary hormone deficiencies were gradually confirmed and substituted. At the MRI, characteristic triad for PSIS (anterior pituitary hypoplasia, interrupted pituitary stalk and ectopic posterior lobe) was diagnosed. We performed a comprehensive genomic screening, including microarrays for structural rearrangements and whole-exome sequencing for a monogenic defect. A novel heterozygous missense variant in the CDON gene (c.1814G > T; p.Gly605Val) was identified. The variant was inherited from the mother, who, besides short stature, did not show any disease symptoms. The variant was absent in control databases and 100 healthy subjects originating from the same population. We report a novel variant in the CDON gene associated with PSIS and congenital cranial nerve palsy. The variant revealed autosomal dominant inheritance with incomplete penetrance in concordance with previous studies reporting CDON defects.
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Affiliation(s)
- Monika Obara-Moszyńska
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland.
| | - Bartłomiej Budny
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Małgorzata Kałużna
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Katarzyna Zawadzka
- MNM Diagnostics Sp. z o.o., 64 Macieja Rataja Str., 61-695, Poznan, Poland
| | - Aleksander Jamsheer
- Department of Medical Genetics, Poznan University of Medical Sciences, 8 Rokietnicka Str, 60-806, Poznan, Poland
| | - Anna Rohde
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland
| | - Marek Ruchała
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Katarzyna Ziemnicka
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Marek Niedziela
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland
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LIM Homeobox 4 (lhx4) regulates retinal neural differentiation and visual function in zebrafish. Sci Rep 2021; 11:1977. [PMID: 33479361 PMCID: PMC7820405 DOI: 10.1038/s41598-021-81211-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 01/04/2021] [Indexed: 01/29/2023] Open
Abstract
LIM homeobox 4 (LHX4) is expressed in the photoreceptors (PRs) of the outer nuclear layer (ONL) and bipolar cells (BCs) of the inner nuclear layer (INL) in mouse and chicken retina. It regulates the subtype-specific development of rod BCs and cone BCs in the mouse retina. However, no report has been published on its expression and function in the zebrafish retina. In this study, we assessed the expression of Lhx4 using in situ hybridization (ISH) technique and explored its role in zebrafish (Danio rerio) retinal development via morpholino (MO) technology. We found that the expression of lhx4 in the zebrafish retina begins 48 h post-fertilization (hpf) and is continuously expressed in the ONL and INL. A zebrafish model constructed with lhx4 knockdown in the eyes through vivo-MO revealed that: lhx4 knockdown inhibits the differentiation of Parvalbumin+ amacrine cells (ACs) and Rhodopsin+ rod photoreceptors (RPs), enhances the expression of visual system homeobox 2 (vsx2); and damages the responses of zebrafish to light stimulus, without affecting the differentiation of OFF-BCs and rod BCs, and apoptosis in the retina. These findings reveal that lhx4 regulates neural differentiation in the retina and visual function during zebrafish embryonic development.
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Abstract
Pituitary stalk interruption syndrome (PSIS) is a distinct developmental defect of the pituitary gland identified by magnetic resonance imaging and characterized by a thin, interrupted, attenuated or absent pituitary stalk, hypoplasia or aplasia of the adenohypophysis, and an ectopic posterior pituitary. The precise etiology of PSIS still remains elusive or incompletely confirmed in most cases. Adverse perinatal events, including breech delivery and hypoxia, were initially proposed as the underlying mechanism affecting the hypothalamic-pituitary axis. Nevertheless, recent findings have uncovered a wide variety of PSIS-associated molecular defects in genes involved in pituitary development, holoprosencephaly (HPE), neural development, and other important cellular processes such as cilia function. The application of whole exome sequencing (WES) in relatively large cohorts has identified an expanded pool of potential candidate genes, mostly related to the Wnt, Notch, and sonic hedgehog signaling pathways that regulate pituitary growth and development during embryogenesis. Importantly, WES has revealed coexisting pathogenic variants in a significant number of patients; therefore, pointing to a multigenic origin and inheritance pattern of PSIS. The disorder is characterized by inter- and intrafamilial variability and incomplete or variable penetrance. Overall, PSIS is currently viewed as a mild form of an expanded HPE spectrum. The wide and complex clinical manifestations include evolving pituitary hormone deficiencies (with variable timing of onset and progression) and extrapituitary malformations. Severe and life-threatening symptomatology is observed in a subset of patients with complete pituitary hormone deficiency during the neonatal period. Nevertheless, most patients are referred later in childhood for growth retardation. Prompt and appropriate hormone substitution therapy constitutes the cornerstone of treatment. Further studies are needed to uncover the etiopathogenesis of PSIS.
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Affiliation(s)
- Antonis Voutetakis
- Department of Pediatrics, School of Medicine, Democritus University of Thrace, Alexandroupolis, Thrace, Greece.
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