| Full text | |
| Author(s): |
Souto-Neto, Jose Araujo
;
David, Daniela Dantas
;
Zanetti, Giovanna
;
Sua-Cespedes, Cristhian
;
Freret-Meurer, Natalie Villar
;
Moraes, Maria Nathalia
;
de Assis, Leonardo Vinicius Monteiro
;
Castrucci, Ana Maria de Lauro
Total Authors: 8
|
| Document type: | Journal article |
| Source: | COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY; v. 288, p. 20-pg., 2023-11-20. |
| Abstract | |
Light is a strong stimulus for the sensory and endocrine systems. The opsins constitute a large family of proteins that can respond to specific light wavelengths. Hippocampus reidi is a near-threatened seahorse that has a diverse color pattern and sexual dimorphism. Over the years, H. reidi's unique characteristics, coupled with its high demand and over-exploitation for the aquarium trade, have raised concerns about its conservation, primarily due to their significant impact on wild populations. Here, we characterized chromatophore types in juvenile and adult H. reidi in captivity, and the effects of specific light wavelengths with the same irradiance (1.20 mW/cm2) on color change, growth, and survival rate. The xanthophores and melanophores were the major components of H. reidi pigmentation with differences in density and distribution between life stages and sexes. In the eye and skin of juveniles, the yellow (585 nm) wavelength induced a substantial increase in melanin levels compared to the individuals kept under white light (WL), blue (442 nm), or red (650 nm) wavelengths. In addition, blue and yellow wavelengths led to a higher juvenile mortality rate in comparison to the other treatments. Adult seahorses showed a rhythmic color change over 24 h, the highest reflectance values were obtained in the light phase, representing a daytime skin lightening for individuals under WL, blue and yellow wavelength, with changes in the acrophase. The yellow wavelength was more effective on juvenile seahorse pigmentation, while the blue wavelength exerted a stronger effect on the regulation of adult physiological color change. Dramatic changes in the opsin mRNA levels were life stage-dependent, which may infer ontogenetic opsin functions throughout seahorses' development. Exposure to specific wavelengths differentially affected the opsins mRNA levels in the skin and eyes of juveniles. In the juveniles, skin transcripts of visual (rh1, rh2, and lws) and non-visual opsins (opn3 and opn4x) were higher in individuals under yellow light. While in the juvenile's eyes, only rh1 and rh2 had increased transcripts influenced by yellow light; the lws and opn3 mRNA levels were higher in juveniles' eyes under WL. Prolonged exposure to yellow wavelength stimulates a robust increase in the antioxidant enzymes sod1 and sod2 mRNA levels. Our findings indicate that changes in the visible light spectrum alter physiological processes at different stages of life in H. reidi and may serve as the basis for a broader discussion about the implications of artificial light for aquatic species in captivity. (AU) | |
| FAPESP's process: | 18/14728-0 - Melanopsin as the UVA photoreceptor and its relationship with pigmentation, DNA repair, biological clock and components of the HPA axis: a novel pharmacological target? |
| Grantee: | Ana Maria de Lauro Castrucci |
| Support Opportunities: | Regular Research Grants |
| FAPESP's process: | 21/01659-2 - Participation of melanopsin in the thermoregulation of mammals |
| Grantee: | Giovanna Zanetti |
| Support Opportunities: | Scholarships in Brazil - Master |
| FAPESP's process: | 17/24615-5 - Breaking a paradigm? Melanopsin, a canonical photo-pigment, acting as sensor to entrain the clock in light unexposed organs, and its putative interaction with TRP channels: a trans-disciplinary study involving physiological and pathological aspects |
| Grantee: | Ana Maria de Lauro Castrucci |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 17/26651-9 - Glaucoma as a model of temporal information disruption: impact on the metabolism |
| Grantee: | Maria Nathália de Carvalho Magalhães Moraes Figueira Borges |
| Support Opportunities: | Research Grants - Young Investigators Grants |
| FAPESP's process: | 18/16511-8 - Involvement of the photosensitive and temporal controlling systems in the development, progression, and metastasis of malignant melanoma: an investigation of novel therapeutic targets |
| Grantee: | Leonardo Vinícius Monteiro de Assis |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 18/23043-0 - Photo- and termo-reception systems in the Blue Crab, Callinectes sapidus (Crustacea Brachyura), and their relationship with the molt cycle |
| Grantee: | Daniela Dantas David |
| Support Opportunities: | Scholarships in Brazil - Doctorate |