Search results for "Melatonin"
showing 10 items of 165 documents
Melatonin in the seasonal response of the aphid Acyrthosiphon pisum.
2018
Aphids display life cycles largely determined by the photoperiod. During the warm long-day seasons, most aphid species reproduce by viviparous parthenogenesis. The shortening of the photoperiod in autumn induces a switch to sexual reproduction. Males and sexual females mate to produce overwintering resistant eggs. In addition to this full life cycle (holocycle), there are anholocyclic lineages that do not respond to changes in photoperiod and reproduce continuously by parthenogenesis. The molecular or hormonal events that trigger the seasonal response (i.e., induction of the sexual phenotypes) are still unknown. Although circadian synthesis of melatonin is known to play a key role in verteb…
Do carotenoid-based sexual traits signal the availability of non-pigmentary antioxidants?
2006
SUMMARY Carotenoid-based signals are thought to be indicators of male quality because they must be obtained from the diet and might thus indicate the ability of individuals to gather high-quality food. However, carotenoids are also known to have important physiological functions as immunoenhancers and antioxidants, and, as such, carotenoid-based sexual traits have also been suggested to reflect the health and antioxidant status of their bearers. This last idea is based on the hypothesis that carotenoids that are allocated to sexual signals are no longer available for the detoxification system. Recently, this hypothesis has been challenged on the grounds that the antioxidant activity is not …
Melatonin Targets Metabolism in Head and Neck Cancer Cells by Regulating Mitochondrial Structure and Function.
2021
This study was funded by grants from the Ministerio de Economia, Industria y Competitividad y por el Fondo de Desarrollo Regional FEDER, Spain nº SAF2013-49019, SAF2017-85903-P, and from the Consejería de Innovación, Ciencia y Empresa, Junta de Andalucía (P07- CTS- 03135, P10- CTS- 5784, and CTS- 101), Spain. J.F. and L.M. have FPU fellowships from the Ministerio de Educación Cultura y Deporte, Spain. C.R.S. was a schorlarship holder from the Plan Propio de Investigación of the University of Granada.
Zinc oxide nanoparticles mediated cytotoxicity, mitochondrial membrane potential and level of antioxidants in presence of melatonin.
2017
Zinc oxide nanoparticles (ZnO NPs) are widely used in a variety of products and are currently being investigated for biomedical applications. However, they have the potential to interact with macromolecules like proteins, lipids and DNA within the cells which makes the safe biomedical application difficult. The toxicity of the ZnO NP is mainly attributed reactive oxygen species (ROS) generation. Different strategies like iron doping, polymer coating and external supply of antioxidants have been evaluated to minimize the toxic potential of ZnO NPs. Melatonin is a hormone secreted by the pineal gland with great antioxidant properties. The melatonin is known to protect cells from ROS inducing …
Circadian Rhythm and Concentration of Melatonin in Breast Cancer Patients
2020
Background: Melatonin is a biomarker of the central circadian clock and its chronobiotic actions entraining circadian rhythms to the light-dark cycle are well known. Reduction in melatonin levels and altered circadian rhythms have been associated with a high risk of breast cancer. Melatonin has also shown to display anti-proliferative effects on breast cancer growth and proliferation. Evaluation of melatonin circadian rhythm alterations in patients bearing breast cancer may have interesting prognostic and therapeutic applications. Objective: To review studies evaluating the circadian rhythm of melatonin in breast cancer patients. The effects of surgery and chemotherapy on melatonin secreti…
Melatonin Treatment Alters Biological and Immunomodulatory Properties of Human Dental Pulp Mesenchymal Stem Cells via Augmented Transforming Growth F…
2020
Melatonin is an endogenous neurohormone with well-reported anti-inflammatory and antioxidant properties, but the direct biological and immunomodulatory effects of melatonin on human dental pulp stem cells (hDPSCs) has not been fully elucidated. The aim of this study was to evaluate the influence of melatonin on the cytocompatibility, proliferation, cell migration, odontogenic differentiation, mineralized nodule formation, and immunomodulatory properties of hDPSCs.To address the melatonin biological effects on hDPSCs, the cytocompatibility, proliferation, cell migration, odontogenic differentiation, mineralized nodule formation, and immunomodulatory properties of hDPSCs after melatonin treat…
Meta-analysis identifies novel risk loci and yields systematic insights into the biology of male-pattern baldness
2017
Male-pattern baldness (MPB) is a common and highly heritable trait characterized by androgen-dependent, progressive hair loss from the scalp. Here, we carry out the largest GWAS meta-analysis of MPB to date, comprising 10,846 early-onset cases and 11,672 controls from eight independent cohorts. We identify 63 MPB-associated loci (P<5 × 10−8, METAL) of which 23 have not been reported previously. The 63 loci explain ∼39% of the phenotypic variance in MPB and highlight several plausible candidate genes (FGF5, IRF4, DKK2) and pathways (melatonin signalling, adipogenesis) that are likely to be implicated in the key-pathophysiological features of MPB and may represent promising targets for the de…
Melatonin enhances neural stem cell differentiation and engraftment by increasing mitochondrial function
2017
Mendivil-Perez, Miguel et al.
Circadian and Dopaminergic Regulation of Fatty Acid Oxidation Pathway Genes in Retina and Photoreceptor Cells.
2016
The energy metabolism of the retina might comply with daily changes in energy demand and is impaired in diabetic retinopathy-one of the most common causes of blindness in Europe and the USA. The aim of this study was to investigate putative adaptation of energy metabolism in healthy and diabetic retina. Hence expression analysis of metabolic pathway genes was performed using quantitative polymerase chain reaction, semi-quantitative western blot and immunohistochemistry. Transcriptional profiling of key enzymes of energy metabolism identified transcripts of mitochondrial fatty acid β-oxidation enzymes, i.e. carnitine palmitoyltransferase-1α (Cpt-1α) and medium chain acyl-CoA dehydrogenase (A…
Determination of melatonin in Acyrthosiphon pisum aphids by liquid chromatography-tandem mass spectrometry.
2015
Melatonin is a hormone mainly involved in the regulation of circadian and seasonal rhythms in both invertebrates and vertebrates. Despite the identification of melatonin in many insects, its involvement in the insect seasonal response remains unclear. A liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed for melatonin analysis in aphids (Acyrthosiphon pisum) for the first time. After comparing two different procedures and five extraction solvents, a sample preparation procedure with a mixture of methanol/water (50:50) was selected for melatonin extraction. The method was validated by analyzing melatonin recovery at three spiked concentrations (5, 50 and 100 p…