-
Medical Physics Mar 2023The formation of concrements in human pineal gland (PG) is a physiological process and, according to many researchers, is associated with the involution of PG...
BACKGROUND
The formation of concrements in human pineal gland (PG) is a physiological process and, according to many researchers, is associated with the involution of PG structures. The majority of scientific publications concern progressive calcification of PG, leaving out studies on the destruction of already formed calcified concrements. Our study fills the gap in knowledge about calcified zones destruction in PG in normal aging and neuropathological conditions, which has not been addressed until now.
PURPOSE
Our objective is to gain insight into human PG tissue impairment in both normal aging and neurodegenerative conditions. X-ray phase-contrast tomography (XPCT) allowed us to study PG tissue degeneration at high spatial resolution and, for the first time, to examine the damaged PG concrements in detail. Our research finding could potentially enhance the understanding of the PG involvement in the process of aging as well as in Alzheimer's disease (AD) and vascular dementia (VD).
METHODS
The research was carried out on human PG autopsy material in normal aging, VD, and AD conditions. Laboratory-based micro-computed tomography (micro-CT) was used to collect and evaluate samples of native, uncut, and unstained PG with different degrees of pineal calcification. The detailed high-resolution 3D images of the selected PGs were produced using synchrotron-based XPCT. Histology and immunohistochemistry of soft PG tissue confirmed XPCT results.
RESULTS
We performed via micro-CT the evaluation of the morphometric parameters of PG such as total sample volume, calcified concrements volume, and percentage of concrements in the total volume of the sample. XPCT imaging revealed high-resolution details of age-related PG alteration. In particular, we noted signs of moderate degradation of concrements in some PGs from elderly donors. In addition, our analysis revealed noticeable degenerative change in both concrements and soft tissue of PGs with neuropathology. In particular, we observed a hollow core and separated layers as well as deep ragged cracks in PG concrements of AD and VD samples. In parenchyma of some samples, we detected wide pinealocyte-free fluid-filled areas adjacent to the calcified zones.
CONCLUSION
The present work provides the basis for future scientific research focused on the dynamic nature of PG calcium deposits and PG soft tissue in normal aging and neurodegenerative diseases.
Topics: Humans; Aged; Pineal Gland; X-Ray Microtomography; Neurodegenerative Diseases; Calcinosis; Alzheimer Disease
PubMed: 36309985
DOI: 10.1002/mp.16080 -
Italian Journal of Pediatrics Mar 2022The causes of an early onset of puberty are still not clearly defined and may vary from subject to subject. In girls, even if 90% of early puberty is idiopathic,...
BACKGROUND
The causes of an early onset of puberty are still not clearly defined and may vary from subject to subject. In girls, even if 90% of early puberty is idiopathic, magnetic resonance imaging (MRI) of the brain is performed to exclude secondary causes of precocious puberty, in particular pathological lesions as hypothalamic tumours (hamartoma). In some cases, other intracranial lesions are considered as incidental findings. Aim of the study is evaluating the prevalence of abnormal intracranial lesions detected by brain magnetic resonance imaging MRI with particular focus on the prevalence of pineal gland cysts in the diagnostic work-up of girls with central precocious puberty (CPP) as onset before 8 years and central early puberty (CEP) as onset before 10 years.
MATERIAL AND METHODS
MRI data of girls referred from January 2010 to December 2015 to the Pediatric Endocrinology Unit of University of Pavia for early onset of breast development were collected.
RESULTS
We collected 123 MRI data of girls referred to the Pediatric Endocrinology Unit of University of Pavia for early onset of breast development in the study period. Out of them, 25 (20.3%) had cerebral abnormalities and 15 (12.2%) had pineal gland cysts. No significant differences were noted in auxological, ultrasound and hormonal parameters at diagnosis among girls with or without pineal cysts. Patients have been observed for at least three years after the discontinuation of therapy. None of our patients had an unfavorable evolution.
CONCLUSIONS
Although pineal cysts seem to be not involved in the onset of puberty, the relevance of the finding remains controversial. Our study wants to provide further insight into the incidence of pineal cysts in pubertal advances. Of note, pineal cysts are often asymptomatic and do not evolve over time.
Topics: Child; Cysts; Endocrine System Diseases; Female; Humans; Pineal Gland; Puberty; Puberty, Precocious
PubMed: 35313951
DOI: 10.1186/s13052-022-01235-4 -
Oral Surgery, Oral Medicine, Oral... Nov 2022This study aims to determine the incidence of physiologic intracranial calcifications on cone beam computed tomography (CBCT) and to contribute to the differentiation...
OBJECTIVES
This study aims to determine the incidence of physiologic intracranial calcifications on cone beam computed tomography (CBCT) and to contribute to the differentiation between physiologic and pathologic intracranial calcifications by sharing their characteristic appearances, with the largest number of patients in the literature and many different types of physiologic calcifications.
STUDY DESIGN
CBCT images of 996 patients admitted to the clinic between 2018 and 2019 were scanned retrospectively. Petroclinoid (PCL) and interclinoid ligaments (ICL), pineal gland, coronoid plexus, falx cerebri, tentorium cerebelli, and other dural calcifications were evaluated in each radiograph.
RESULTS
Physiologic calcification was present in 49.4% of the cases, and pineal gland calcification was the most common (47.6%) type. PCL calcification was detected in 22.1%, and it was mostly bilateral partial. There were complete ICL in 1.2%, coronoid plexus in 11.3%, falx cerebri in 6.3%, tentorium cerebelli in 1.1%, and other dural calcifications in 3.6%. Only PCL calcifications differed between sexes and were more common in males. PCL, pineal gland, and coronoid plexus calcifications were most detected in the third decade of the cases.
CONCLUSIONS
Intracranial calcifications are detected incidentally in CBCT examinations. Some calcifications may indicate pathologic conditions, and patients may need to be referred for further evaluation.
Topics: Male; Humans; Retrospective Studies; Calcinosis; Cone-Beam Computed Tomography; Calcification, Physiologic; Pineal Gland
PubMed: 35701294
DOI: 10.1016/j.oooo.2022.04.050 -
Methods in Molecular Biology (Clifton,... 2022The human pineal gland regulates the day-night dynamics of multiple physiological processes, especially through the secretion of melatonin. Recently, using mass...
The human pineal gland regulates the day-night dynamics of multiple physiological processes, especially through the secretion of melatonin. Recently, using mass spectrometry-based proteomics and dedicated analysis tools, we have identified regulated proteins and signaling pathways that differ between day and night and/or between control and autistic pineal glands. This large-scale proteomic approach is the method of choice to study proteins in a biological system globally. This chapter proposes a protocol for large-scale analysis of the pineal gland proteome.
Topics: Circadian Rhythm; Humans; Mass Spectrometry; Melatonin; Pineal Gland; Proteome; Proteomics
PubMed: 36180685
DOI: 10.1007/978-1-0716-2593-4_16 -
Neuroendocrinology 2017The nocturnal production of melatonin by the pineal gland is triggered by sympathetic activation of adrenoceptors and may be modulated by immunological signals. The...
BACKGROUND/AIM
The nocturnal production of melatonin by the pineal gland is triggered by sympathetic activation of adrenoceptors and may be modulated by immunological signals. The effect of glucocorticoids on nocturnal melatonin synthesis is controversial; both stimulatory and inhibitory effects have been reported. During pathophysiological processes, an increased sympathetic tonus could result in different patterns of adrenoceptor activation in the pineal gland. Therefore, in this investigation, we evaluated whether the pattern of adrenergic stimulation of the pineal gland drives the direction of the glucocorticoid effect on melatonin production.
METHODS
The corticosterone effect on the pineal hormonal production induced by β-adrenoceptor or β+α1-adrenoceptor activation was evaluated in cultured glands. We also investigated whether the in vivo lipopolysaccharide (LPS)-induced inhibition of melatonin is dependent on the interaction of glucocorticoids and the α1-adrenoceptor in adrenalectomized animals and on the in vivo blockade of glucocorticoid receptors (GRs) or the α1-adrenoceptor.
RESULTS
Corticosterone potentiated β-adrenoceptor-induced pineal melatonin synthesis, whilst corticosterone-dependent inhibition was observed when melatonin production was induced by β+α1-adrenoceptors agonists. The inhibitory effect of corticosterone is mediated by GR, as it was abolished in the presence of a GR antagonist. Moreover, LPS-induced reduction in melatonin nocturnal plasma content was reversed by adrenalectomy and by antagonizing GR or α1-adrenoceptors.
CONCLUSIONS
The dual effect of corticosterone on pineal melatonin synthesis is determined by the activation pattern of adrenoceptors (β or β+α1) in the gland during GR activation, suggesting that increased activation of the sympathetic system and the hypothalamic-pituitary-adrenal axis are necessary for the control of melatonin production during defense responses.
Topics: Adrenergic beta-Agonists; Animals; Catecholamines; Corticosterone; Inflammation; Isoproterenol; Lipopolysaccharides; Male; Melatonin; Pineal Gland; Rats; Rats, Wistar; Receptors, Adrenergic, alpha-1; Receptors, Adrenergic, beta
PubMed: 26954684
DOI: 10.1159/000445189 -
Journal of Pineal Research Apr 2021The human pineal gland regulates day-night dynamics of multiple physiological processes, especially through the secretion of melatonin. Using mass-spectrometry-based...
The human pineal gland regulates day-night dynamics of multiple physiological processes, especially through the secretion of melatonin. Using mass-spectrometry-based proteomics and dedicated analysis tools, we identify proteins in the human pineal gland and analyze systematically their variation throughout the day and compare these changes in the pineal proteome between control specimens and donors diagnosed with autism. Results reveal diverse regulated clusters of proteins with, among others, catabolic carbohydrate process and cytoplasmic membrane-bounded vesicle-related proteins differing between day and night and/or control versus autism pineal glands. These data show novel and unexpected processes happening in the human pineal gland during the day/night rhythm as well as specific differences between autism donor pineal glands and those from controls.
Topics: Autistic Disorder; Case-Control Studies; Circadian Rhythm; Humans; Pineal Gland; Protein Interaction Maps; Proteins; Proteome; Proteomics; Spectrometry, Mass, Electrospray Ionization; Tandem Mass Spectrometry; Time Factors
PubMed: 33368564
DOI: 10.1111/jpi.12713 -
Effects of different light intensities on the transcriptome changes of duck retina and pineal gland.Poultry Science Jun 2022The light intensity can affect the production performance of animals. The retina and pineal gland, closely linked, are directly photosensitive organs. This study...
The light intensity can affect the production performance of animals. The retina and pineal gland, closely linked, are directly photosensitive organs. This study evaluated the effect of light intensity on duck growth and investigated the effects of varying light intensities on retina and pineal gland transcriptome changes. The increase of light intensity will significantly decrease production performance, such as body weight, eviscerated weight, breast muscle weight, percentage of abdominal fat, etc. The RNA-seq revealed 967 and 201 differentially expressed genes (DEGs) in the retina and pineal gland under different light intensities, respectively. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) in the retina showed the DEGs were enriched in ECM-receptor interaction, Focal adhesion, Cell adhesion molecules (CAMs), Cytokine-cytokine receptor interaction, Melanogenesis, etc. Meanwhile, the DEGs in the pineal gland were mainly enriched in pathways associated with the mTOR signaling pathway, melanin production pathway, etc. Our results indicated that different light intensities might affect the function of the retina and pineal gland, including the melanin production of the retina and the secretion of melatonin in the pineal gland. Our study can provide a theoretical basis for the molecular mechanism of the effects of different light intensities on the retina and pineal gland.
Topics: Animals; Chickens; Ducks; Melanins; Pineal Gland; Retina; Transcriptome
PubMed: 35490498
DOI: 10.1016/j.psj.2022.101819 -
Anatomical Science International Mar 2023Several experimental intents require pineal gland removal. The main challenge of the pinealectomy surgical procedure is the hemorrhage due to the transverse sinus torn....
BACKGROUND
Several experimental intents require pineal gland removal. The main challenge of the pinealectomy surgical procedure is the hemorrhage due to the transverse sinus torn. The study aimed to modify the rat pinealectomy surgical procedure to reduce the risk of bleeding and the mortality rate.
METHODS
Adult male rats experienced pinealectomy surgery. A mini-drill was used to remove a small skull area in the junction of the lambda and sagittal sutures. The pineal gland was removed using a curved-head hook. Animals experienced intensive post-surgical care. Locomotion, cerebellar motor function, working memory, and anxiety were evaluated 2 weeks after pinealectomy by the open field, rotarod, Y maze, and the elevated plus maze, respectively.
RESULTS
Surgical modification reduced the bleeding risk and animal mortality rate. No significant alteration was found in locomotion and working memory. However, the pinealectomy was anxiogenic and decreased entry to the open arm. The cerebellar motor performance did not change in the rotarod test. Hematoxylin-Eosin staining of removed tissue confirmed the histology of the pineal gland.
CONCLUSION
Advantages of this technique were removing a small skull area, modifying the hook insertion point to prevent damaging the brain veins, reducing the bleeding risk and the mortality rate. Surgery modification was associated with a decreased final number of animals used. Regardless of the melatonin shortage, pinealectomy affects different organs, which should be considered in the research study design.
Topics: Rats; Animals; Male; Pineal Gland; Pinealectomy; Melatonin
PubMed: 36029435
DOI: 10.1007/s12565-022-00683-6 -
Gene Feb 2018The proteins of Ly-6 (lymphocyte antigen-6) family are involved in the regulation of immunoreaction, cell migration and adhesion, and neuronal excitability. However,...
The proteins of Ly-6 (lymphocyte antigen-6) family are involved in the regulation of immunoreaction, cell migration and adhesion, and neuronal excitability. However, little is known about the function of Ly-6 proteins in embryogenesis. Herein, we identified a GPI anchored Ly-6 member named ly6 expressed in pineal gland and eye (lypge). Dynamic expression pattern of lypge was revealed by whole mount in situ hybridization. It was strikingly expressed in the pineal gland and cone photoreceptor, and its expression was regulated by orthodenticle homolog 5 (otx5) which has been shown to control the expression of many pineal genes. In addition, we demonstrated that lypge was rhythmically expressed in larvae from 4dpf on. Moreover, knockdown of lypge resulted in small head and small eye formed in zebrafish embryos. These suggest that Lypge is involved in the formation of the eye and pineal gland in early development of zebrafish.
Topics: Animals; Cloning, Molecular; Eye; GPI-Linked Proteins; Gene Expression Profiling; Gene Expression Regulation, Developmental; Models, Molecular; Organ Specificity; Otx Transcription Factors; Phylogeny; Pineal Gland; Zebrafish; Zebrafish Proteins
PubMed: 29196253
DOI: 10.1016/j.gene.2017.11.062 -
Experimental Neurology Oct 2021The functional roles of microRNAs (miRNAs) have been studied in various diseases, including hypoxic-ischemic brain damage (HIBD). However, changes in the expression of...
The functional roles of microRNAs (miRNAs) have been studied in various diseases, including hypoxic-ischemic brain damage (HIBD). However, changes in the expression of miRNAs and the underlying mechanisms in the pineal gland during HIBD remain unknown. Based on the previous study by microRNA array, hundreds of miRNAs showed altered expression patterns in the pineal gland in a rat model of HIBD. MiR-375-3p was found to be significantly upregulated and abundant in the pineal gland. Further investigation in an in vitro HI model of pinealocytes showed that miRNA-375 exacerbated the damage to pineal function. After oxygen-glucose deprivation / reoxygenation (OGD/R), miR-375-3p expression increased, while aralkylamine N-acetyltransferase (AANAT) expression and melatonin (MT) secretion decreased. Overexpression of miRNA-375 in pinealocytes aggravated the influence of OGD/R on AANAT expression and MT secretion. Because miRNA-375 overexpression in pinealocytes induced decreased rasd1 mRNA and protein expression, rasd1 may mediate the effect of miR-375-3p on pineal function. Furthermore, miR-375-3p aggravated the cognitive impairment caused by HIBD in rats, as observed by Morris water maze test, and also affected emotion and circadian rhythm in HIBD-treated rats. Thus, miR-375-3p may be a key regulatory molecule in the pineal gland following HIBD, and targeting of miR-375-3p may represent a new strategy for the treatment of HIBD.
Topics: Animals; Circadian Rhythm; Cognitive Dysfunction; Emotions; Female; Hypoxia-Ischemia, Brain; Male; MicroRNAs; Pineal Gland; Rats; Rats, Sprague-Dawley
PubMed: 34280452
DOI: 10.1016/j.expneurol.2021.113814