-
Annals of Medicine Feb 1998In photoperiodic nonhuman mammals the secretion of melatonin from the pineal gland plays a major role in regulating reproductive physiology; in humans these... (Review)
Review
In photoperiodic nonhuman mammals the secretion of melatonin from the pineal gland plays a major role in regulating reproductive physiology; in humans these relationships are less clear. The melatonin rhythm changes throughout life with the first substantial change in nocturnal melatonin secretion being reportedly associated with puberty. The transition from Tanner stage 1 to Tanner stage 5 of sexual maturation is associated with a significant reduction in nocturnal melatonin levels, but a cause-effect relationship has not been established. Menstrual cyclicity has been reported to be associated with fluctuations in melatonin production but whether they are related to, eg ovulation or menstruation is not established. At high latitudes the quantity of melatonin produced by the pineal gland varies with season (changes in the light-dark cycle), and there is some evidence that this changes reproductive efficiency accordingly. Menopause is associated with a reduction in melatonin which may relate to the changing gonadotropin levels. In males of the same age melatonin levels also drop with no significant alteration in reproductive physiology. While correlations between melatonin and the status of the reproductive system in humans have been noted, whether they are functionally related remains to be determined.
Topics: Adult; Animals; Circadian Rhythm; Female; Humans; Male; Melatonin; Menopause; Middle Aged; Pineal Gland; Pregnancy; Reproduction; Seasons; Sexual Maturation
PubMed: 9556096
DOI: 10.3109/07853899808999391 -
Brain and Behavior Jul 2020Cultural traditions attribute to pineal gland an important role for spiritual experiences. Mediumship and spirit possession are cultural phenomena found worldwide which...
BACKGROUND
Cultural traditions attribute to pineal gland an important role for spiritual experiences. Mediumship and spirit possession are cultural phenomena found worldwide which have been described as having dissociative and psychotic-like characteristics, but with nonpathological aspects. A sympathetic activation pattern in response to spirit possession has been reported in some studies, but empirical data on pineal gland is scarce in this context.
METHODS
We aimed to investigate pineal gland and pituitary volumes, as well as urinary 6-sulfatoxymelatonin levels in 16 alleged mediums (Medium Group-MG) compared with 16 healthy nonmedium controls (Control Group) (Experiment 1). Furthermore, we aimed to evaluate urinary 6-sulfatoxymelatonin and stress reactivity in GM (n = 10) under different physiological conditions (Experiment 2).
RESULTS
In Experiment 1, MG presented higher scores of anomalous experiences, but there were no between-group differences regarding mental health or subjective sleep quality. Similar pineal gland and pituitary volumes were observed between groups. There were no between-group differences in urinary 6-sulfatoxymelatonin collected under equivalent baseline conditions. In Experiment 2, the rise of anxiety and heart rate in response to mediumistic experience was intermediate between a nonstressful control task (reading) and a stressful control task (Trier Social Stress Test-TSST). No significant differences were observed in 6-sulfatoxymelatonin urinary levels between the three conditions. The pattern of stress reactivity during the TSST was normal, but with an attenuated salivary cortisol response.
CONCLUSION
The normal neuroimaging and stress reactivity findings in MG contrast with the abnormal results usually observed in subjects with psychotic and dissociative disorders.
Topics: Anxiety; Dissociative Disorders; Female; Humans; Hydrocortisone; Pineal Gland; Pituitary-Adrenal System; Spirit Possession; Stress, Psychological
PubMed: 32506697
DOI: 10.1002/brb3.1693 -
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 -
Behavioural Processes Jul 2016Melatonin is a hormone rhythmically secreted at night by the pineal gland in vertebrates. In diurnal mammals, melatonin is present during the inactive phase of the...
Melatonin is a hormone rhythmically secreted at night by the pineal gland in vertebrates. In diurnal mammals, melatonin is present during the inactive phase of the rest/activity cycle, and in primates it directly facilitates sleep and decreases body temperature. However, the role of the pineal gland for the promotion of sleep at night has not yet been studied in non-primate diurnal mammalian species. Here, the authors directly examined the hypothesis that the pineal gland contributes to diurnality in Nile grass rats by decreasing activity and increasing sleep at night, and that this could occur via effects on circadian mechanisms or masking, or both. Removing the pineal gland had no effect on the hourly distribution of activity across a 12:12 light-dark (LD) cycle or on the patterns of sleep-like behavior at night. Masking effects of light at night on activity were also not significantly different in pinealectomized and control grass rats, as 1h pulses of light stimulated increases in activity of sham and pinealectomized animals to a similar extent. In addition, the circadian regulation of activity was unaffected by the surgical condition of the animals. Our results suggest that the pineal gland does not contribute to diurnality in the grass rat, thus highlighting the complexity of temporal niche transitions. The current data raise interesting questions about how and why genetic and neural mechanisms linking melatonin to sleep regulatory systems might vary among mammals that reached a diurnal niche via parallel and independent pathways.
Topics: Animals; Circadian Rhythm; Female; Light; Motor Activity; Muridae; Photoperiod; Pineal Gland; Sleep
PubMed: 27038859
DOI: 10.1016/j.beproc.2016.03.007 -
Journal of Neuro-oncology Jan 2024To provide a treatment-focused review and develop basic treatment guidelines for patients diagnosed with pineal anlage tumor (PAT).
PURPOSE
To provide a treatment-focused review and develop basic treatment guidelines for patients diagnosed with pineal anlage tumor (PAT).
METHODS
Prospectively collected data of three patients with pineal anlage tumor from Germany was combined with clinical details and treatment information from 17 published cases.
RESULTS
Overall, 20 cases of PAT were identified (3 not previously reported German cases, 17 cases from published reports). Age at diagnosis ranged from 0.3 to 35.0 (median: 3.2 ± 7.8) years. All but three cases were diagnosed before the age of three years. For three cases, metastatic disease at initial staging was described. All patients underwent tumor surgery (gross-total resection: 9, subtotal resection/biopsy: 9, extent of resection unknown: 2). 15/20 patients were alive at last follow-up. Median follow-up for 10/15 surviving patients with available follow-up and treatment data was 2.4 years (0.3-6.5). Relapse was reported for 3 patients within 0.8 years after diagnosis. Five patients died, 3 after relapse and 2 from early postoperative complications. Two-year-progression-free- and -overall survival were 65.2 ± 12.7% and 49.2 ± 18.2%, respectively. All 4 patients who received intensive chemotherapy including high-dose chemotherapy combined with radiotherapy (2 focal, 2 craniospinal [CSI]) had no recurrence. Focal radiotherapy- and CSI-free survival rates in 13 evaluable patients were 46.2% (6/13) and 61.5% (8/13), respectively.
CONCLUSION
PAT is an aggressive disease mostly affecting young children. Therefore, adjuvant therapy using intensive chemotherapy and considering radiotherapy appears to comprise an appropriate treatment strategy. Reporting further cases is crucial to evaluate distinct treatment strategies.
Topics: Adolescent; Adult; Child; Child, Preschool; Humans; Infant; Young Adult; Brain Neoplasms; Neoplasm Recurrence, Local; Pineal Gland; Pinealoma; Recurrence; Supratentorial Neoplasms; Treatment Outcome
PubMed: 38253790
DOI: 10.1007/s11060-023-04547-5 -
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 -
Oncotarget Mar 2016Deficits in neuroendocrine-immune system functioning, including alterations in pineal and thymic glands, contribute to aging-associated diseases. This study looks at...
Deficits in neuroendocrine-immune system functioning, including alterations in pineal and thymic glands, contribute to aging-associated diseases. This study looks at ageing-associated alterations in pineal and thymic gland functioning evaluating common signaling molecules present in both human and animal pinealocytes and thymocytes: endocrine cell markers (melatonin, serotonin, pCREB, AANAT, CGRP, VIP, chromogranin Ð); cell renovation markers (p53, AIF, Ki67), matrix metalloproteinases (MMP2, MMP9) and lymphocytes markers (CD4, CD5, CD8, CD20). Pineal melatonin is decreased, as is one of the melatonin pathway synthesis enzymes in the thymic gland. A further similarity is the increased MMPs levels evident over age in both glands. Significant differences are evident in cell renovation processes, which deteriorate more quickly in the aged thymus versus the pineal gland. Decreases in the number of pineal B-cells and thymic T-cells were also observed over aging. Collected data indicate that cellular involution of the pineal gland and thymus show many commonalities, but also significant changes in aging-associated proteins. It is proposed that such ageing-associated alterations in these two glands provide novel pharmaceutical targets for the wide array of medical conditions that are more likely to emerge over the course of ageing.
Topics: Aged; Aged, 80 and over; Aging; Biomarkers; Cell Proliferation; Cells, Cultured; Female; Humans; Male; Middle Aged; Pineal Gland; Signal Transduction; Thymus Gland
PubMed: 26943046
DOI: 10.18632/oncotarget.7863 -
Journal of Neurochemistry Sep 2011Retina and anterior neural fold homeobox (Rax) gene encodes a transcription factor essential for vertebrate eye development. Recent microarray studies indicate that Rax...
Retina and anterior neural fold homeobox (Rax) gene encodes a transcription factor essential for vertebrate eye development. Recent microarray studies indicate that Rax is expressed in the adult rat pineal gland and retina. The present study reveals that Rax expression levels in the rat change significantly during retinal development with a peak occurring at embryonic day 18, whereas Rax expression in the pineal is relatively delayed and not detectable until embryonic day 20. In both tissues, Rax is expressed throughout postnatal development into adulthood. In the mature rat pineal gland, the abundance of Rax transcripts increases 2-fold during the light period with a peak occurring at dusk. These findings are consistent with the evidence that Rax is of functional importance in eye development and suggest a role of Rax in the developing pineal gland. In addition, it would appear possible that Rax contributes to phenotype maintenance in the mature retina and pineal gland and may facilitate 24-h changes in the pineal transcriptome.
Topics: Aging; Animals; Blotting, Western; Circadian Rhythm; Gene Expression Profiling; Gene Expression Regulation, Developmental; Homeodomain Proteins; In Situ Hybridization; Male; Pineal Gland; RNA, Messenger; Rats; Rats, Sprague-Dawley; Retina
PubMed: 21749377
DOI: 10.1111/j.1471-4159.2011.07385.x -
Psychiatria Danubina Sep 2016In obese individuals impaired sleep and neuroendocrine alterations such as melatonin deficits are associated with circadian rhythm disruption, altered circadian clock...
BACKGROUND
In obese individuals impaired sleep and neuroendocrine alterations such as melatonin deficits are associated with circadian rhythm disruption, altered circadian clock gene expression, and bright light at night. While the relation of pineal gland volume (PGV) and melatonin levels has recently been documented in humans, surprisingly little is known about the possible interference of the PGV and the pathophysiology of obesity in humans.
SUBJECTS AND METHODS
We therefore compared the PGV of obese with non-obese individuals; both groups were matched by age and gender. Volumetric analyses were performed on the basis of 3 Tesla high resolution Magnetic Resonance Imaging (MRI).
RESULTS
We found, that the PGV was significantly smaller in obese individuals than in lean controls (P=0.036). Moreover, PGV and waist-hip ratio showed a significant negative association in controls (P=0.018, r=-0.602) whereas no association of both variables was found in obese individuals (P=0.856, r=-0.051).
CONCLUSIONS
Thus, the current pilot investigation suggests that pineal gland function, reflected by PGV might be involved in the energy homeostasis and pathophysiological mechanisms that contribute to the development and the maintenance of obesity in humans. Moreover, our data supports the notion that the replacement of melatonin deficits might be a novel strategy in the treatment of obesity.
Topics: Animals; Body Mass Index; Circadian Rhythm; Energy Metabolism; Female; Homeostasis; Humans; Image Interpretation, Computer-Assisted; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Male; Melatonin; Obesity; Organ Size; Pilot Projects; Pineal Gland; Reference Values; Sleep; Statistics as Topic
PubMed: 27658830
DOI: No ID Found