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Physiological Research Dec 2019The pineal gland (glandula pinealis) is neuroendocrine gland located at the epithalamus of the brain secreting melatonin. The aim of this study was to explore effects of...
The pineal gland (glandula pinealis) is neuroendocrine gland located at the epithalamus of the brain secreting melatonin. The aim of this study was to explore effects of prenatal hypoxia in rats at the age of 33 weeks on the occurrence of pineal gland calcification. Distribution and chemical composition of calcerous material by light, scanning and transmission electron microscopy was investigated. Melatonin concentrations in blood plasma by direct radioimmunoassay were measured. Rats were exposed to prenatal hypoxia for 12 h at day 20 of development and second group to prenatal hypoxia for 2x8 h at days 19 and 20 of development. Vacuoles of intracellular edema in the pineal samples after 12 h hypoxia were found. Their size ranges up to 30 µm. Some of them were filled with the flocculent and fibrous material. Samples of pineal glands after 2 x 8 h hypoxia revealed the pericellular edema of pinealocytes. The amount of calcium rich particles in 2 x 8 h hypoxia group was lower than in 12 h hypoxia group. Plasma melatonin levels did not differ between control and both hypoxia groups. We concluded that calcification is a process induced by osteoblasts and osteocytes with melatonin as a promotor and it is favored under hypoxic conditions.
Topics: Animals; Calcinosis; Hypoxia; Male; Pineal Gland; Rats, Wistar
PubMed: 32118471
DOI: 10.33549/physiolres.934378 -
NeuroImage. Clinical 2021Magnetic resonance imaging (MRI) studies reported pineal gland atrophy in schizophrenia patients and individuals at a clinical high risk of developing psychosis,...
BACKGROUND
Magnetic resonance imaging (MRI) studies reported pineal gland atrophy in schizophrenia patients and individuals at a clinical high risk of developing psychosis, implicating abnormalities in melatonin secretion in the pathophysiology of psychosis. However, it currently remains unclear whether the morphology of the pineal gland contributes to symptomatology and sociocognitive functions.
METHODS
This MRI study examined pineal gland volumes and the prevalence of pineal cysts as well as their relationship with clinical characteristics in 57 at risk mental state (ARMS) subjects, 63 patients with schizophrenia, and 61 healthy controls. The Social and Occupational Functioning Assessment Scale (SOFAS), the Schizophrenia Cognition Rating Scale (SCoRS), and the Brief Assessment of Cognition in Schizophrenia (BACS) were used to assess sociocognitive functions, while the Positive and Negative Syndrome Scale was employed to evaluate clinical symptoms in ARMS subjects and schizophrenia patients.
RESULTS
Pineal gland volumes were significantly smaller in the ARMS and schizophrenia groups than in the controls, while no significant differences were observed in the prevalence of pineal cysts. Although BACS, SCoRS, and SOFAS scores were not associated with pineal morphology, patients with pineal cysts in the schizophrenia group exhibited severe positive psychotic symptoms with rather mild negative symptoms.
CONCLUSION
The present results indicate the potential of pineal atrophy as a vulnerability marker in various stages of psychosis and suggest that pineal cysts influence the clinical subtype of schizophrenia.
Topics: Atrophy; Cysts; Humans; Magnetic Resonance Imaging; Pineal Gland; Psychotic Disorders; Schizophrenia
PubMed: 34461434
DOI: 10.1016/j.nicl.2021.102805 -
Journal of Medicine and Life 2014Melatonin is an indoleamine produced by the pineal gland and secreted in a circadian manner. In the past few decades, research over this topic has been enhanced.... (Review)
Review
Melatonin is an indoleamine produced by the pineal gland and secreted in a circadian manner. In the past few decades, research over this topic has been enhanced. Melatonin has many important roles in the human physiology: regulator of the circadian rhythms, sleep inducer, antioxidant, anticarcinogenic. This paper reviews the involvement of melatonin in embryo fetal development. The pineal gland develops completely postpartum, so both the embryo and the fetus are dependent on the maternal melatonin provided transplacentally. Melatonin appears to be involved in the normal outcome of pregnancy beginning with the oocyte quality and finishing with the parturition. Its pregnancy night-time concentrations increase after 24 weeks of gestation, with significantly high levels after 32 weeks. Melatonin receptors are widespread in the embryo and fetus since early stages. There is solid evidence that melatonin is neuroprotective and has a positive effect on the outcome of the compromised pregnancies. In addition, chronodisruption leads to a reproductive dysfunction. Thus, the influence of melatonin on the developing human fetus may not be limited to the entertaining of circadian rhythmicity, but further studies are needed.
Topics: Embryo, Mammalian; Female; Fertilization in Vitro; Fetal Development; Humans; Melatonin; Pineal Gland; Pregnancy; Receptors, Melatonin
PubMed: 25713608
DOI: No ID Found -
Journal of Cancer Research and... Jan 2023Germ cell tumor of the central nervous system (CNS) is an infrequent entity consisting of only 0.2%-1.7% of all primary CNS tumors. The pineal gland is the commonest... (Review)
Review
Germ cell tumor of the central nervous system (CNS) is an infrequent entity consisting of only 0.2%-1.7% of all primary CNS tumors. The pineal gland is the commonest location of CNS germinoma. Traditionally, radiotherapy alone has been used to treat localized pineal germinoma, which has delivered a very high cure rate. Spinal drop metastases from pineal germinoma can develop after a long time from diagnosis and primary treatment. Currently, craniospinal irradiation is the standard of care in metastatic pineal germinoma with spinal drop metastases along with systemic chemotherapy. Very few cases of pineal germinoma with spinal drop metastases have been published in the literature. We report a pineal gland germinoma case with spinal drop metastases in an 18-year-old boy and reviewed the published literature.
Topics: Male; Humans; Adolescent; Pineal Gland; Germinoma; Brain Neoplasms; Neoplasms, Germ Cell and Embryonal
PubMed: 38384076
DOI: 10.4103/jcrt.jcrt_657_22 -
Journal of Pineal Research Mar 2020The pineal gland is a neuroendocrine organ responsible for production of the nocturnal hormone melatonin. A specific set of homeobox gene-encoded transcription factors...
The pineal gland is a neuroendocrine organ responsible for production of the nocturnal hormone melatonin. A specific set of homeobox gene-encoded transcription factors govern pineal development, and some are expressed in adulthood. The brain-specific homeobox gene (Bsx) falls into both categories. We here examined regulation and function of Bsx in the mature pineal gland of the rat. We report that Bsx is expressed from prenatal stages into adulthood, where Bsx transcripts are localized in the melatonin-synthesizing pinealocytes, as revealed by RNAscope in situ hybridization. Bsx transcripts were also detected in the adult human pineal gland. In the rat pineal gland, Bsx was found to exhibit a 10-fold circadian rhythm with a peak at night. By combining in vivo adrenergic stimulation and surgical denervation of the gland in the rat with in vitro stimulation and transcriptional inhibition in cultured pinealocytes, we show that rhythmic expression of Bsx is controlled at the transcriptional level by the sympathetic neural input to the gland acting via adrenergic stimulation with cyclic AMP as a second messenger. siRNA-mediated knockdown (>80% reduction) in pinealocyte cultures revealed Bsx to be a negative regulator of other pineal homeobox genes, including paired box 4 (Pax4), but no effect on genes encoding melatonin-synthesizing enzymes was detected. RNA sequencing analysis performed on siRNA-treated pinealocytes further revealed that downstream target genes of Bsx are mainly involved in developmental processes. Thus, rhythmic Bsx expression seems to govern other developmental regulators in the mature pineal gland.
Topics: Animals; Circadian Rhythm; Female; Gene Expression Regulation, Developmental; Male; Melatonin; Nerve Tissue Proteins; Pineal Gland; Rats, Sprague-Dawley; Transcription Factors
PubMed: 31808568
DOI: 10.1111/jpi.12629 -
Molecular and Cellular Endocrinology Jan 2010Microarray analysis has provided a new understanding of pineal function by identifying genes that are highly expressed in this tissue relative to other tissues and also... (Review)
Review
Microarray analysis has provided a new understanding of pineal function by identifying genes that are highly expressed in this tissue relative to other tissues and also by identifying over 600 genes that are expressed on a 24-h schedule. This effort has highlighted surprising similarity to the retina and has provided reason to explore new avenues of study including intracellular signaling, signal transduction, transcriptional cascades, thyroid/retinoic acid hormone signaling, metal biology, RNA splicing, and the role the pineal gland plays in the immune/inflammation response. The new foundation that microarray analysis has provided will broadly support future research on pineal function.
Topics: Animals; Circadian Rhythm; Humans; Melatonin; Neurons; Oligonucleotide Array Sequence Analysis; Pineal Gland; Signal Transduction
PubMed: 19622385
DOI: 10.1016/j.mce.2009.07.010 -
Revista Da Associacao Medica Brasileira... 2015The pineal gland is responsible for producing a hormone called melatonin (MEL), and is accepted as the gland that regulates reproduction in mammals. Prolactin (PRL) also... (Review)
Review
The pineal gland is responsible for producing a hormone called melatonin (MEL), and is accepted as the gland that regulates reproduction in mammals. Prolactin (PRL) also exhibits reproductive activity in animals in response to photoperiod. It is known that the concentrations of PRL are high in the summer and reduced during winter, the opposite of what is seen with melatonin in these seasons. In placental mammals, both prolactin and melatonin affect implantation, which is considered a critical point of pregnancy, since a successful pregnancy requires the development of a synchronous interaction between the endometrium and blastocyst for placental development. It is also known that PRL levels during pregnancy are essential for the maintenance of pregnancy, because this hormone induces the corpus luteum to produce progesterone, in addition to stimulating blastocyst implantation to maintain pregnancy and form the placenta. However, melatonin levels in plasma have also been shown to increase during pregnancy, peaking at the end of this period, which suggests that this hormone plays an important role in the maintenance of pregnancy. Thus, it is clear that treatment with prolactin or melatonin interferes with the processes responsible for the development and maintenance of pregnancy.
Topics: Animals; Blastocyst; Cell Proliferation; Embryo Implantation; Female; Humans; Melatonin; Photoperiod; Pineal Gland; Pregnancy; Prolactin; Reproduction
PubMed: 26248251
DOI: 10.1590/1806-9282.61.03.269 -
Journal of Pineal Research May 2022The pineal gland is a neuroendocrine structure in the brain, which produces and secretes the hormone melatonin at nighttime and is considered a key element in the...
The pineal gland is a neuroendocrine structure in the brain, which produces and secretes the hormone melatonin at nighttime and is considered a key element in the circadian clock system. Early morphogenesis of the gland is controlled by a number of transcription factors, some of which remain active in adult life. One of these is the brain-specific homeobox (Bsx), a highly conserved homeodomain transcription factor with a developmental role in the pineal gland of several species, including zebrafish, and regulatory roles in mature pinealocytes of the rat. To determine the role of Bsx in circadian biology, we here examined the effects of a bsx loss-of-function mutation on the pineal gland in adult zebrafish and on behavioral circadian rhythms in larvae. In pineal cell type-specific Gfp/Egfp reporter zebrafish lines, we did not detect fluorescence signals in the pineal area of homozygous (bsx ) mutants. Interestingly, a nonpigmented area on the dorsal surface of the head above the gland, known as the pineal window, was pigmented in the homozygous mutants. Furthermore, a structure corresponding to the pineal gland was not detectable in the midline of the adult brain in histological sections analyzed by Nissl staining and S-antigen immunohistochemistry. Moreover, the levels of pineal transcripts were greatly reduced in bsx mutants, as revealed by quantitative real-time polymerase chain reaction analysis. Notably, analysis of locomotor activity at the larval stage revealed altered circadian rhythmicity in the bsx mutants with periods and phases similar to wildtype, but severely reduced amplitudes in locomotor activity patterns. Thus, Bsx is essential for full development of the pineal gland, with its absence resulting in a phenotype of morphological pineal gland ablation and disrupted circadian behavior.
Topics: Animals; Circadian Rhythm; DNA-Binding Proteins; Gene Expression Regulation, Developmental; Melatonin; Nerve Tissue Proteins; Pineal Gland; Rats; Transcription Factors; Zebrafish
PubMed: 35249239
DOI: 10.1111/jpi.12795 -
Hormones (Athens, Greece) Jul 2017
Topics: History, 15th Century; History, 16th Century; History, 17th Century; History, 18th Century; History, 19th Century; History, 20th Century; History, Ancient; History, Medieval; Humans; Pineal Gland
PubMed: 29278521
DOI: 10.14310/horm.2002.1751 -
BioMed Research International 2014Neuropeptide Y was isolated from the porcine brain in 1982 and shown to be colocalized with noradrenaline in sympathetic nerve terminals. The peptide has been...
Neuropeptide Y was isolated from the porcine brain in 1982 and shown to be colocalized with noradrenaline in sympathetic nerve terminals. The peptide has been demonstrated to be present in sympathetic nerve fibers innervating the pineal gland in many mammalian species. In this investigation, we show by use of immunohistochemistry that neuropeptide Y is present in nerve fibers of the adult human pineal gland. The fibers are classical neuropeptidergic fibers endowed with large boutons en passage and primarily located in a perifollicular position with some fibers entering the pineal parenchyma inside the follicle. The distance from the immunoreactive terminals to the pinealocytes indicates a modulatory function of neuropeptide Y for pineal physiology. Some of the immunoreactive fibers might originate from neurons located in the brain and be a part of the central innervation of the pineal gland. In a series of human fetuses, neuropeptide Y-containing nerve fibers was present and could be detected as early as in the pineal of four- to five-month-old fetuses. This early innervation of the human pineal is different from most rodents, where the innervation starts postnatally.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Child; Female; Fetus; Humans; Male; Middle Aged; Nerve Fibers; Neuropeptide Y; Pineal Gland; Rodentia; Species Specificity
PubMed: 24757681
DOI: 10.1155/2014/868567