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Current Medicinal Chemistry 2023Melatonin, mainly released from the pineal gland, also produced in the reproductive organs and cells, plays important roles in rhythms of the sleep-wake cycle,... (Review)
Review
Melatonin, mainly released from the pineal gland, also produced in the reproductive organs and cells, plays important roles in rhythms of the sleep-wake cycle, retardation of ageing processes, and antioxidant/anti-inflammatory functions. As a key mediator in reproductive systems, melatonin is participated in the reproductive process via regulating gamete and embryo development and influences reproductive diseases and pregnancy outcomes. The underlying mechanisms include epigenetic and other regulations, which are interesting for exploring new targets in the prevention and treatment of reproductive diseases. This review discusses the relationship between melatonin and reproductive functions and dysfunction, as well as potential clinical applications of melatonin in reproductive medicine. Notably, Developmental Origins of Health and Diseases (DOHaD) is closely linked to reproduction, this article is the first to review the new progress in studies on the possible relationship between melatonin and DOHaD.
Topics: Pregnancy; Female; Humans; Melatonin; Pineal Gland; Reproduction; Antioxidants; Reproductive Medicine; Circadian Rhythm
PubMed: 36200146
DOI: 10.2174/0929867329666221005101031 -
Methods in Molecular Biology (Clifton,... 2022Mammalian pineal glands are composed mostly of pinealocytes, which are the melatonin secretory cells, and also importantly of glial cells in special astrocytes. With the...
Mammalian pineal glands are composed mostly of pinealocytes, which are the melatonin secretory cells, and also importantly of glial cells in special astrocytes. With the aim of studying the interactions between pinealocytes and astrocytes, the methodologies for obtaining and maintaining isolated pinealocytes and astrocytes in culture were standardized, in addition to the co-culture of both cell types. Some works of our group were published on the interactions between isolated astrocytes and pinealocytes from the pineal gland of Wistar rats, considering the modulatory role of glutamate and angiotensin on the synthesis of melatonin. In this chapter, the methodologies for obtaining and maintaining astrocytes and pinealocytes culture as well as co-culture of these two cell types will be presented.
Topics: Angiotensins; Animals; Astrocytes; Cells, Cultured; Coculture Techniques; Glutamic Acid; Mammals; Melatonin; Pineal Gland; Rats; Rats, Wistar
PubMed: 36180680
DOI: 10.1007/978-1-0716-2593-4_11 -
Aging Jan 2020We aimed to investigate the association of pineal gland volume with the risk of isolated rapid eye movement (REM) sleep behavior disorder (RBD). We enrolled 245...
We aimed to investigate the association of pineal gland volume with the risk of isolated rapid eye movement (REM) sleep behavior disorder (RBD). We enrolled 245 community-dwelling cognitively normal elderly individuals without major psychiatric or neurological disorders at the baseline evaluation, of whom 146 completed the 2-year follow-up evaluation. We assessed RBD symptoms using the REM Sleep Behavior Disorder Screening Questionnaire (RBDSQ) and defined probable RBD (pRBD) as an RBDSQ score of ≥ 5. We manually segmented the pineal gland on 3T T1-weighted brain magnetic resonance imaging and estimated its volume. The smaller the baseline pineal gland volume, the more severe the RBD symptoms at baseline. The individuals with isolated pRBD showed smaller pineal gland volumes than those without isolated pRBD. The larger the baseline pineal gland volume, the lower the risks of prevalent isolated pRBD at the baseline evaluation and incident isolated pRBD at the 2-year follow-up evaluation. Pineal gland volume showed good diagnostic accuracy for prevalent isolated pRBD and predictive accuracy for incident isolated pRBD in the receiver operator characteristic analysis. Our findings suggest that pineal gland volume may be associated with the severity of RBD symptoms and the risk of isolated RBD in cognitively normal elderly individuals.
Topics: Age Factors; Aged; Aged, 80 and over; Aging; Disease Susceptibility; Female; Humans; Incidence; Male; Organ Size; Pineal Gland; Prevalence; REM Sleep Behavior Disorder; ROC Curve; Risk Assessment; Risk Factors
PubMed: 31918412
DOI: 10.18632/aging.102661 -
BMC Genomic Data Feb 2021Long noncoding RNA (lncRNA) has been identified as important regulator in hypothalamic-pituitary-ovarian axis associated with sheep prolificacy. However, little is known...
BACKGROUND
Long noncoding RNA (lncRNA) has been identified as important regulator in hypothalamic-pituitary-ovarian axis associated with sheep prolificacy. However, little is known of their expression pattern and potential roles in the pineal gland of sheep. Herein, RNA-Seq was used to detect transcriptome expression pattern in pineal gland between follicular phase (FP) and luteal phase (LP) in FecB (MM) and FecB (ww) STH sheep, respectively, and differentially expressed (DE) lncRNAs and mRNAs associated with reproduction were identified.
RESULTS
Overall, 135 DE lncRNAs and 1360 DE mRNAs in pineal gland between MM and ww sheep were screened. Wherein, 39 DE lncRNAs and 764 DE mRNAs were identified (FP vs LP) in MM sheep, 96 DE lncRNAs and 596 DE mRNAs were identified (FP vs LP) in ww sheep. Moreover, GO and KEGG enrichment analysis indicated that the targets of DE lncRNAs and DE mRNAs were annotated to multiple biological processes such as phototransduction, circadian rhythm, melanogenesis, GSH metabolism and steroid biosynthesis, which directly or indirectly participate in hormone activities to affect sheep reproductive performance. Additionally, co-expression of lncRNAs-mRNAs and the network construction were performed based on correlation analysis, DE lncRNAs can modulate target genes involved in related pathways to affect sheep fecundity. Specifically, XLOC_466330, XLOC_532771, XLOC_028449 targeting RRM2B and GSTK1, XLOC_391199 targeting STMN1, XLOC_503926 targeting RAG2, XLOC_187711 targeting DLG4 were included.
CONCLUSION
All of these differential lncRNAs and mRNAs expression profiles in pineal gland provide a novel resource for elucidating regulatory mechanism underlying STH sheep prolificacy.
Topics: Animals; Female; Follicular Phase; Genotype; Luteal Phase; Pineal Gland; RNA, Long Noncoding; RNA, Messenger; Sheep; Transcriptome
PubMed: 33602139
DOI: 10.1186/s12863-020-00957-w -
Nature Sep 2023The neurocranium is an integral part of the vertebrate head, itself a major evolutionary innovation. However, its early history remains poorly understood, with great...
The neurocranium is an integral part of the vertebrate head, itself a major evolutionary innovation. However, its early history remains poorly understood, with great dissimilarity in form between the two living vertebrate groups: gnathostomes (jawed vertebrates) and cyclostomes (hagfishes and lampreys). The 100 Myr gap separating the Cambrian appearance of vertebrates from the earliest three-dimensionally preserved vertebrate neurocrania further obscures the origins of modern states. Here we use computed tomography to describe the cranial anatomy of an Ordovician stem-group gnathostome: Eriptychius americanus from the Harding Sandstone of Colorado, USA. A fossilized head of Eriptychius preserves a symmetrical set of cartilages that we interpret as the preorbital neurocranium, enclosing the fronts of laterally placed orbits, terminally located mouth, olfactory bulbs and pineal organ. This suggests that, in the earliest gnathostomes, the neurocranium filled out the space between the dermal skeleton and brain, like in galeaspids, osteostracans and placoderms and unlike in cyclostomes. However, these cartilages are not fused into a single neurocranial unit, suggesting that this is a derived gnathostome trait. Eriptychius fills a major temporal and phylogenetic gap in our understanding of the evolution of the gnathostome head, revealing a neurocranium with an anatomy unlike that of any previously described vertebrate.
Topics: Animals; Fossils; Hagfishes; Imaging, Three-Dimensional; Lampreys; Mouth; Olfactory Bulb; Phylogeny; Pineal Gland; Skull; Tomography Scanners, X-Ray Computed; Vertebrates; Colorado; Cartilage
PubMed: 37730987
DOI: 10.1038/s41586-023-06538-y -
Journal of Pineal Research Jan 2024The pineal gland has evolved from a photoreceptive organ in fish to a neuroendocrine organ in mammals. This study integrated multiple daytime single-cell RNA-seq...
The pineal gland has evolved from a photoreceptive organ in fish to a neuroendocrine organ in mammals. This study integrated multiple daytime single-cell RNA-seq datasets from the pineal glands of zebrafish, rats, and monkeys, providing a detailed examination of the evolutionary transition at single-cell resolution. We identified key factors responsible for the anatomical and functional transformation of the pineal gland. We retrieved and integrated daytime single-cell transcriptomic datasets from the pineal glands of zebrafish, rats, and monkeys, resulting in a total of 22 431 cells after rigorous quality filtering. Comparative analysis was then conducted to elucidate the evolution of pineal cells, their photosensitivity, their role in melatonin production, and the signaling processes within the glands of these species. Our analysis identified distinct cellular compositions of the pineal gland in zebrafish, rats, and monkeys. Zebrafish photoreceptors exhibited comprehensive phototransduction gene expression, while specific genes, including transducin (Gngt1, Gnb3, and Gngt2) and phosducin (Pdc), were consistently present in mammalian pinealocytes. We found transcriptional similarities between the pineal gland and retina, underscoring shared evolutionary and functional pathways. Zebrafish displayed unique light-responsive circadian gene activity compared to rats and monkeys. Key ligand-receptor interactions were identified, especially involving MDK and PTN, influencing melatonin synthesis across species. Furthermore, we observed species-specific GPCR (G protein-coupled receptors) expressions related to melatonin synthesis and their alignment with retinal expressions. Our findings also highlighted specific transcription factors (TFs) and regulatory networks associated with pineal gland evolution and function. Our study provides a detailed analysis of the pineal gland's evolution from fish to mammals. We identified key transcriptional changes and controls that highlight the gland's functional diversity. Notably, we found significant ligand-receptor interactions influencing melatonin synthesis and demonstrated parallels between pineal and retinal expressions. These insights enhance our understanding of the pineal gland's role in phototransduction, melatonin production, and circadian rhythms in vertebrates.
Topics: Animals; Rats; Pineal Gland; Melatonin; Zebrafish; Ligands; Circadian Rhythm; Mammals
PubMed: 38018267
DOI: 10.1111/jpi.12927 -
Molecular and Cellular Endocrinology Mar 2020In mammals, the pineal gland is the sole endocrine source of melatonin, which is secreted according to daily and seasonal patterns. This mini-review synthesizes the... (Review)
Review
In mammals, the pineal gland is the sole endocrine source of melatonin, which is secreted according to daily and seasonal patterns. This mini-review synthesizes the established endocrine actions of melatonin in the following temporal contexts. Melatonin is a strictly regulated output of the circadian timing system, but under certain conditions, may also entrain the circadian pacemaker and clocks in peripheral tissues. As the waveform of nightly melatonin secretion varies seasonally, melatonin provides a hormonal representation of the time of year. The duration of elevated melatonin secretion regulates reproductive physiology and other seasonal adaptations either by entraining a circannual rhythm or by inducing seasonal responses directly. An entrainment action of nightly melatonin on clock gene expression in the pars tuberalis of the anterior pituitary may partly underly its mechanistic role as a photoperiodic switch. Melatonin has important functions developmentally to regulate multiple physiological systems and program timing of puberty. Endogenous melatonergic systems are disrupted by modern lifestyles of humans through altered circadian entrainment, acute suppression by light and self-administration of pharmacological melatonin. Non-endocrine actions of locally synthesized melatonin fall outside of the scope of this mini-review.
Topics: Animals; CLOCK Proteins; Circadian Clocks; Circadian Rhythm; Gene Expression; Humans; Mammals; Melatonin; Photoperiod; Pineal Gland; Seasons; Signal Transduction; Time Factors
PubMed: 31866317
DOI: 10.1016/j.mce.2019.110687 -
Morphologie : Bulletin de L'Association... Jun 2023The current study was conducted in the Department of Anatomy, Osmania Medical College, Koti, Hyderabad over a period of 1year. A total of 30 human pineal glands...
The current study was conducted in the Department of Anatomy, Osmania Medical College, Koti, Hyderabad over a period of 1year. A total of 30 human pineal glands (16-males,11-females,3 excluded for post-mortem autolysis) from those bodies between the age groups of 1-80years were collected during the post-mortem study at the Mortuary of Osmania General Hospital, Koti, Hyderabad and were included in the study. Morphological parameters like weight and transverse diameter at the maximum width of the pineal glands were measured and then the pineal glands were processed for light microscopy. 4-5micron thick sections were cut and stained with H&E and Masson Trichrome for highlighting the connective tissue pattern of the pineal gland. Under light microscope, the capsular delineation, pattern of septation and lobulation, calcification, intracellular brown pigment, intraparenchymal inflammatory cells, fibrosis, gliosis and cystic changes in the pineal glands were observed in relation to age and gender.
Topics: Male; Female; Humans; Infant; Child, Preschool; Child; Adolescent; Young Adult; Adult; Middle Aged; Aged; Aged, 80 and over; Pineal Gland; Calcinosis; Calcification, Physiologic; Staining and Labeling; Microscopy
PubMed: 35786527
DOI: 10.1016/j.morpho.2022.06.095 -
Journal of Pineal Research Mar 2021Our daily rhythmicity is controlled by a circadian clock with a specific set of genes located in the suprachiasmatic nucleus in the hypothalamus. Mast cells (MCs) are... (Review)
Review
Our daily rhythmicity is controlled by a circadian clock with a specific set of genes located in the suprachiasmatic nucleus in the hypothalamus. Mast cells (MCs) are major effector cells that play a protective role against pathogens and inflammation. MC distribution and activation are associated with the circadian rhythm via two major pathways, IgE/FcεRI- and IL-33/ST2-mediated signaling. Furthermore, there is a robust oscillation between clock genes and MC-specific genes. Melatonin is a hormone derived from the amino acid tryptophan and is produced primarily in the pineal gland near the center of the brain, and histamine is a biologically active amine synthesized from the decarboxylation of the amino acid histidine by the L-histidine decarboxylase enzyme. Melatonin and histamine are previously reported to modulate circadian rhythms by pathways incorporating various modulators in which the nuclear factor-binding near the κ light-chain gene in B cells, NF-κB, is the common key factor. NF-κB interacts with the core clock genes and disrupts the production of pro-inflammatory cytokine mediators such as IL-6, IL-13, and TNF-α. Currently, there has been no study evaluating the interdependence between melatonin and histamine with respect to circadian oscillations in MCs. Accumulating evidence suggests that restoring circadian rhythms in MCs by targeting melatonin and histamine via NF-κB may be promising therapeutic strategy for MC-mediated inflammatory diseases. This review summarizes recent findings for circadian-mediated MC functional roles and activation paradigms, as well as the therapeutic potentials of targeting circadian-mediated melatonin and histamine signaling in MC-dependent inflammatory diseases.
Topics: Animals; Circadian Rhythm; Histamine; Histidine Decarboxylase; Humans; Interleukin-13; Interleukin-6; Mast Cells; Melatonin; Pineal Gland; Tumor Necrosis Factor-alpha
PubMed: 33020940
DOI: 10.1111/jpi.12699 -
Identifying daily changes in circRNAs and circRNA-associated-ceRNA networks in the rat pineal gland.International Journal of Medical... 2021Circular RNAs (circRNAs) are a new class of covalently closed circular RNA molecules that are involved in many biological processes. However, information about circRNAs...
Circular RNAs (circRNAs) are a new class of covalently closed circular RNA molecules that are involved in many biological processes. However, information about circRNAs in the pineal gland, particularly that of rats, is limited. To establish resources for the study of the rat pineal gland, we performed transcriptome analysis of the pineal glands during the day and night. In this study, 1413 circRNAs and 1989 miRNAs were identified in the pineal gland of rats during the night and day using the Illumina platform. Forty differentially expressed circRNAs and 93 differentially expressed miRNAs were obtained, among which 20 circRNAs and 37 miRNAs were significantly upregulated during the day and 20 circRNAs and 56 miRNAs were significantly upregulated during the night. As circRNAs have been reported to work as miRNA sponges, we predicted 15940 interactions among 40 circRNAs, 93 miRNAs and 400 mRNAs with differential diurnal expression using miRanda and TargetScan to build a ceRNA regulatory network in the rat pineal gland. The diurnal expression profile of circRNAs in the rat pineal gland may provide additional information about the role of circRNAs in regulating changes in melatonin circadian rhythms. The analyzed data reported in this study will be an important resource for future studies to elucidate the altered physiology of circRNAs in diurnal rhythms.
Topics: Animals; Circadian Rhythm; Gene Expression Profiling; Gene Expression Regulation; Gene Regulatory Networks; Male; Melatonin; MicroRNAs; Models, Animal; Photoperiod; Pineal Gland; RNA, Circular; RNA, Messenger; Rats
PubMed: 33526984
DOI: 10.7150/ijms.51743