melatonin production
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2022 ◽  
Vol 30 (3) ◽  
pp. 26-30
Author(s):  
Oscar H. Del Brutto ◽  
Robertino M. Mera

Abstract Background: This study assesses whether pineal gland calcification (PGC) – a surrogate for reduced endogenous melatonin production – is associated with significant stenosis of large intracranial arteries – a biomarker of intracranial atherosclerotic disease (ICAD). Methods: Individuals aged ≥60 years enrolled in the Three Villages Study received head CT to assess PGC and MRA to estimate stenosis of large intracranial arteries. Multivariate logistic regression models were fitted to assess the association between PGC and ICAD, after adjusting for relevant confounders. Inverse probability of exposure weighting was used to estimate the effect of PGC on ICAD. Results: A total of 581 individuals were enrolled. PGC and ICAD were associated in a fully-adjusted logistic regression model (p=0.032). Inverse probability of exposure weighting showed an estimate for the proportion of ICAD among those without PGC of 3.7% and the adjusted-effect coefficient was 5.7% higher among those with PGC (p=0.031). Conclusions: PGC is associated with ICAD. Study results provide grounds for evaluating the role of melatonin deficiency in ICAD progression. Keywords: Pineal gland calcification, intracranial atherosclerosis, stenosis of large intracranial arteries, melatonin; population study, older adults


2022 ◽  
Vol 12 ◽  
Author(s):  
Laura Gabriela Nisembaum ◽  
Guillaume Loentgen ◽  
Thibaut L’Honoré ◽  
Patrick Martin ◽  
Charles-Hubert Paulin ◽  
...  

Fish are ectotherm, which rely on the external temperature to regulate their internal body temperature, although some may perform partial endothermy. Together with photoperiod, temperature oscillations, contribute to synchronizing the daily and seasonal variations of fish metabolism, physiology and behavior. Recent studies are shedding light on the mechanisms of temperature sensing and behavioral thermoregulation in fish. In particular, the role of some members of the transient receptor potential channels (TRP) is being gradually unraveled. The present study in the migratory Atlantic salmon, Salmo salar, aims at identifying the tissue distribution and abundance in mRNA corresponding to the TRP of the vanilloid subfamilies, TRPV1 and TRPV4, and at characterizing their putative role in the control of the temperature-dependent modulation of melatonin production—the time-keeping hormone—by the pineal gland. In Salmo salar, TRPV1 and TRPV4 mRNA tissue distribution appeared ubiquitous; mRNA abundance varied as a function of the month investigated. In situ hybridization and immunohistochemistry indicated specific labeling located in the photoreceptor cells of the pineal gland and the retina. Additionally, TRPV analogs modulated the production of melatonin by isolated pineal glands in culture. The TRPV1 agonist induced an inhibitory response at high concentrations, while evoking a bell-shaped response (stimulatory at low, and inhibitory at high, concentrations) when added with an antagonist. The TRPV4 agonist was stimulatory at the highest concentration used. Altogether, the present results agree with the known widespread distribution and role of TRPV1 and TRPV4 channels, and with published data on trout (Oncorhynchus mykiss), leading to suggest these channels mediate the effects of temperature on S. salar pineal melatonin production. We discuss their involvement in controlling the timing of daily and seasonal events in this migratory species, in the context of an increasing warming of water temperatures.


2021 ◽  
Author(s):  
Soyhan Bagci ◽  
Astrid Wieduwilt ◽  
Ebru Aileen Alsat ◽  
Jana Blickwedel ◽  
Brigitte Strizek ◽  
...  

Abstract Maternal circadian rhythms are important for maintaining maternal and fetal homeostasis. The maternal circadian system coordinates the internal clock of the fetus with environmental lighting conditions via the melatonin signal. The intensity and wavelength of daylight influence nocturnal melatonin production. This study aims to evaluate the effect of environmental lighting conditions on melatonin production in pregnant women with reduced mobility during hospitalization. We installed a human-centric lighting system with biodynamic effects (BDL, biodynamic lighting) in the patient rooms. The pregnant women in the patient rooms with standard indoor conditions served as a control group. The illuminance (lux) and dose of effective circadian irradiation (Hec) were recorded every 10 seconds by light dosimeters (Lucerne University, Switzerland) attached to the patients` clothing. We analyzed the illuminance status of 47 pregnant women with a median (IQR) gestational age of 29.9 (25.4-32.3) weeks of gestation. The median illuminance in the control group was significantly lower (p<0.05) than in the BDL group in the morning and afternoon from day 1 to 5. BDL patients had a significantly higher effective circadian irradiation in the morning. The effective circadian irradiation showed a significant daily rhythm only in the BDL group. The BDL group had a significantly higher melatonin production on day 3 (p=0.006) and day 6 (p=0.012) than the control group (median (IQR) 15840 (10140-22160) ng vs. 6141 (2080-11328) ng/n on day 3 and 18780 (11320-23562) ng vs. 6380 (3500-17600) ng on day 6). We have demonstrated that dramatically altered lighting conditions of hospitalized pregnant women may be optimized by installing biodynamic lighting systems in the patient rooms resulting in the maintenance of nocturnal melatonin production in pregnant women.


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7302
Author(s):  
Dun-Xian Tan ◽  
Rüdiger Hardeland

In this article, we attempt to classify a potential dimorphism of melatonin production. Thus, a new concept of “reserve or maximum capacity of melatonin synthetic function” is introduced to explain the subtle dimorphism of melatonin production in mammals. Considering ASMT/ASMTL genes in the pseudoautosomal region of sex chromosomes with high prevalence of mutation in males, as well as the sex bias of the mitochondria in which melatonin is synthesized, we hypothesize the existence of a dimorphism in melatonin production to favor females, which are assumed to possess a higher reserve capacity for melatonin synthesis than males. Under physiological conditions, this subtle dimorphism is masked by the fact that cells or tissues only need baseline melatonin production, which can be accomplished without exploiting the full potential of melatonin’s synthetic capacity. This capacity is believed to exceed the already remarkable nocturnal increase as observed within the circadian cycle. However, during aging or under stressful conditions, the reserve capacity of melatonin’s synthetic function is required to be activated to produce sufficiently high levels of melatonin for protective purposes. Females seem to possess a higher reserve/maximum capacity for producing more melatonin than males. Thus, this dimorphism of melatonin production becomes manifest and detectable under these conditions. The biological significance of the reserve/maximum capacity of melatonin’s synthetic function is to improve the recovery rate of organisms from injury, to increase resistance to pathogen infection, and even to enhance their chances of survival by maximizing melatonin production under stressful conditions. The higher reserve/maximum capacity of melatonin synthesis in females may also contribute to the dimorphism in longevity, favoring females in mammals.


2021 ◽  
Vol 53 ◽  
pp. S514-S515
Author(s):  
G. D'orsi ◽  
E.M.T. Melloni ◽  
M. Paolini ◽  
S. Dallaspezia ◽  
S. Poletti ◽  
...  

Fermentation ◽  
2021 ◽  
Vol 7 (4) ◽  
pp. 290
Author(s):  
Vanesa Postigo ◽  
Margarita García ◽  
Juan Mariano Cabellos ◽  
Teresa Arroyo

Multiple studies in recent years have shown the potential of Saccharomyces wild yeasts to produce craft beers with new flavour profiles and other desirable properties. Yeasts isolated from food (wine, bread, kombucha…) have shown potential promise for application in brewing. The aim of this study is to evaluate the ability of 141 Saccharomyces yeast strains isolated from the Madrilenian agriculture (from grapes, must, wine, vineyard, and cellars) to produce a novel ale beer. Fermentation activity of the strains was compared against the commercial strain Saccharomyces cerevisiae Safale S-04. In addition to the other aspects such as melatonin production, thirty-three volatile compounds belonging to higher alcohols, esters, aldehydes/cetones, acids, lactones and phenolic groups, were analysed by GC for selection of the strains. Ten strains were finally chosen, among which the most relevant was the strain G 520 showing a higher production of esters, higher alcohols and acids compared with S-04. The apparent attenuation for this strain was lower than commercial strain, which translates into more residual sugars. Furthermore, G 520 was more capable of producing significantly higher amounts of melatonin studied by HPLC, as well as showing a higher antioxidant capacity. Consumer study showed that G 520 strain could be used to produce a potential beer that has a place in the current market.


2021 ◽  
Vol 12 ◽  
Author(s):  
Francisco J. Valenzuela-Melgarejo ◽  
Constanza Lagunas ◽  
Fabiola Carmona-Pastén ◽  
Kevins Jara-Medina ◽  
Gustavo Delgado

Hypertension can be induced by the disruption of factors in blood pressure regulation. This includes several systems such as Neurohumoral, Renin-angiotensin-aldosterone, the Circadian clock, and melatonin production, which can induce elevation and non-dipping blood pressure. Melatonin has a supraphysiological role as a chronobiotic agent and modulates vascular system processes via pro/antiangiogenic factors, inflammation, the immune system, and oxidative stress regulation. An elevation of melatonin production is observed during pregnancy, modulating the placenta and fetus’s physiological functions. Their impairment production can induce temporal desynchronization of cell proliferation, differentiation, or invasion from trophoblast cells results in vascular insufficiencies, elevating the risk of poor fetal/placental development. Several genes are associated with vascular disease and hypertension during pregnancy via impaired inflammatory response, hypoxia, and oxidative stress, such as cytokines/chemokines IL-1β, IL-6, IL-8, and impairment expression in endothelial cells/VSMCs of HIF1α and eNOS genes. Pathological placentas showed differentially expressed genes (DEG), including vascular genes as CITED2, VEGF, PL-II, PIGF, sFLT-1, and sENG, oncogene JUNB, scaffolding protein CUL7, GPER1, and the pathways of SIRT/AMPK and MAPK/ERK. Additionally, we observed modification of subunits of NADPH oxidase and extracellular matrix elements, i.e., Glypican and Heparanase and KCa channel. Mothers with a low level of melatonin showed low production of proangiogenic factor VEGF, increasing the risk of preeclampsia, premature birth, and abortion. In contrast, melatonin supplementation can reduce systolic pressure, prevent oxidative stress, induce the activation of the antioxidants system, and lessen proteinuria and serum level of sFlt-1. Moreover, melatonin can repair the endothelial damage from preeclampsia at the placenta level, increasing PIGF, Nrf-2, HO-1 production and reducing critical markers of vascular injury during the pregnancy. Melatonin also restores the umbilical and uterine blood flow after oxidative stress and inhibits vascular inflammation and VCAM-1, Activin-A, and sEng production. The beneficial effects of melatonin over pathological pregnancies can be partially observed in normal pregnancies, suggesting the dual role of/over placental physiology could contribute to protection and have therapeutic applications in vascular pathologies of pregnancies in the future.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jian Jiao ◽  
Yan Xia ◽  
Yingli Zhang ◽  
Xueli Wu ◽  
Chonghuai Liu ◽  
...  

Melatonin acts both as an antioxidant and as a growth regulatory substance in plants. Pseudomonas fluorescens endophytic bacterium has been shown to produce melatonin and increase plant resistance to abiotic stressors through increasing endogenous melatonin. However, in bacteria, genes are still not known to be melatonin-related. Here, we reported that the bacterial phenylalanine 4-hydroxylase (PAH) may be involved in the 5-hydroxytryptophan (5-HTP) biosynthesis and further influenced the subsequent production of melatonin in P. fluorescens. The purified PAH protein of P. fluorescens not only hydroxylated phenylalanine but also exhibited l-tryptophan (l-Trp) hydroxylase activity by converting l-Trp to 5-HTP in vitro. However, bacterial PAH displayed lower activity and affinity for l-Trp than l-phenylalanine. Notably, the PAH deletion of P. fluorescens blocked melatonin production by causing a significant decline in 5-HTP levels and thus decreased the resistance to abiotic stress. Overall, this study revealed a possible role for bacterial PAH in controlling 5-HTP and melatonin biosynthesis in bacteria, and expanded the current knowledge of melatonin production in microorganisms.


Life ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1105
Author(s):  
Simona Moravcová ◽  
Eva Filipovská ◽  
Veronika Spišská ◽  
Irena Svobodová ◽  
Jiří Novotný ◽  
...  

In rodents, the melatonin production by the pineal gland is controlled through adrenergic signaling from the suprachiasmatic nuclei and regulation of the principal enzyme in its synthesis, arylalkylamine-N-acetyltransferase (AANAT). In the present study, we identified increased isoprenaline-induced aa-nat expression and nocturnal AANAT activity in the pineal glands in response to the silencing of the signal transducer and activator of transcription 3 (STAT3) with siRNA or STAT3 inhibitors WP1066 and AZD1480. This AANAT activity enhancement in vivo did not interfere with light-induced AANAT suppression. Systemic or in vitro lipopolysaccharide (LPS) administration markedly increased Stat3 expression and STAT3 phosphorylation, but it did not significantly affect AANAT expression or activity. Simultaneous LPS administration and Stat3 silencing enhanced the aa-nat transcription and AANAT activity to a similar extent as Stat3 inhibition without LPS co-administration. Furthermore, we describe the circadian rhythmicity in Stat3 expression and the phosphorylated form of STAT3 protein in the rat pineal gland. Our data suggest that the higher nocturnal endogenous level of STAT3 in the pineal gland decelerates or hampers the process of NA-induced AANAT activation or affects the AANAT enzyme stability.


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