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1.
An Acad Bras Cienc ; 94(1): e20190862, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35018990

RESUMO

Fifteen species of sea anemones (Cnidaria, Actiniaria) have been recorded so far in the Colombian Caribbean, comprising approximately 28% of the total number of known species in the Caribbean Sea. Most species recorded are associated with coral reef communities. However, in the region, no records of sea anemones are known from areas with high sedimentation conditions as is characteristic along the coastline of the Atlántico Department, in Colombia. In this area, organisms are exposed to a high degree of turbidity and sedimentation (~143.9x106 t year-1) as a result of their proximity to the Magdalena River mouth and the 26 micro-basins that flow along its coastline. Several observations and collections were made on soft bottoms, rocky, and artificial substrates in the sectors of Puerto Velero and Caño Dulce to determine the fauna that exist under these conditions. Four species of sea anemones were found belonging to the families Actiniidae and Aiptasiidae, and images from living specimens and cnidae are provided. Bunodosoma cavernatum and Exaiptasia diaphana are here recorded for the first time from the Colombian Caribbean. An updated list of sea anemones in the Colombian Caribbean, now comprising 34 taxa (i.e., 21 species and 13 identified at supra-specific levels), is provided.


Assuntos
Antozoários , Anêmonas-do-Mar , Animais , Região do Caribe , Colômbia , Humanos , Rios
2.
Sci Total Environ ; 806(Pt 4): 150964, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656596

RESUMO

Marine microplastics (MPs)-induced threats to shallow-water scleractinian corals are a growing global concern that needs interdisciplinary studies. However, it remains uncertain to what extent the ecotoxicological effects of MPs can explain the potential health impacts on corals at the species-specific scale. Using recent datasets of multiple MPs-induced impacts on coral species, we developed an integrated ecotoxicological modeling approach to quantify the MPs-corals interaction dynamics. Toxicokinetic (TK)-based corals ingestion, egestion, and adhesion processes posed by MPs were comprehensively evaluated. Based on estimated uptake and egestion rates, we showed that corals were much likely to bioaccumulate marine MPs. We applied toxicodynamic (TD) models to appraise time- and concentration-dependent response patterns across MPs-corals systems. We found that marine MPs are highly toxic to corals with a median benchmark concentration causing 10% compromised coral health of 20-40 mg L-1 and a mean growth inhibition rate of ~2% d-1. By providing these key quantitative metrics that may inform scientists to refine existing management strategies to better understand the long-term impact of MPs on coral reef ecosystems. Our TK/TD modeling scheme can help integrating current toxicological findings to encompass a more mechanistic-, ecological-, and process-based understanding of diverse coral ecosystems that are sensitive to MPs stressor varied considerably by species and taxonomic group.


Assuntos
Antozoários , Microplásticos , Animais , Recifes de Corais , Ecossistema , Plásticos , Toxicocinética
3.
Ecotoxicol Environ Saf ; 229: 113074, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34915224

RESUMO

The amino acid metabolism-related herbicides glufosinate and glyphosate are used worldwide and have flowed into the oceans, threatening the marine organisms. In the present study, physiological activities and transcriptomic profiles of the scleractinian coral Pocillopora damicornis and symbiotic Symbiodiniaceae were determined during a 48 h-exposure to the two herbicides with the final concentration of 10 µmol L-1. Coral samples were collected at 0, 12, 24, and 48 h after exposure to determine symbiont density, chlorophyll content, as well as activities of superoxide dismutase (SOD), catalase (CAT), nitric oxide synthetase (NOS) and phenoloxidase (PO), and the caspase-3 levels, and the samples collected at 24 h were employed in the transcriptomic analysis. Specifically, the symbiont densities did not change significantly in response to the two herbicides, while the chlorophyll content increased significantly at 24 h post glufosinate exposure. SOD and CAT activities in the coral host increased significantly at 12 h after glufosinate and glyphosate exposure, while the activity of NOS in symbionts decreased significantly at 48 h after glufosinate exposure. Caspase-3 levels in the coral host declined significantly at 24 h after exposure to the two herbicides. In the transcriptomic analysis, glufosinate triggered the expression of genes related to the response to stimuli and immunoregulation in the coral host, and suppressed the expression of genes related to coral nitrogen-related metabolism, symbiont cell cycle, and response to nutrient levels. Furthermore, glyphosate activated the expression of genes involved in coral calcification and symbiont nutrient export and suppressed the expression of genes involved in coral meiosis and symbiont cell communication. These results suggest that although the coral-Symbiodiniaceae symbiosis is not disrupted, short-term glufosinate and glyphosate exposures alter several essential physiological processes including metabolism, calcification, and meiosis in the coral host, as well as the cell cycle and nutrient export in the symbiont. SUMMARY: Glufosinate and glyphosate herbicide exposures can disturb several essential physiological processes, including metabolism, calcification, and meiosis in the coral host as well as the cell cycle and nutrient export in the symbiont, threating the survival of scleractinian corals.


Assuntos
Antozoários , Dinoflagelados , Herbicidas , Aminobutiratos , Animais , Antozoários/genética , Dinoflagelados/genética , Glicina/análogos & derivados , Herbicidas/toxicidade , Simbiose , Transcriptoma
4.
Environ Pollut ; 294: 118665, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902525

RESUMO

Coral reefs are amongst the most biodiverse ecosystems on earth, but are significantly impacted by agricultural runoff. Despite herbicides being commonly detected in coastal waters, the possibility of herbicide accumulation in coral reef species has largely been overlooked. We investigate the accumulation of several herbicides in five species of coral reef invertebrates collected from ten sites along the Maputaland coast, South Africa. Multiple herbicide residues were detected in 95% of the samples, with total average concentrations across sites ranging between 25.2 ng g-1 to 51.3 ng g-1 dw. Acetochlor, alachlor and hexazinone were the predominant herbicides detected at all sites, with atrazine and simazine detected less frequently. Significant interactive effects were detected between sites nested in reef complex crossed with species, based on multiple and total herbicide concentrations. In general, multivariate herbicide concentrations varied significantly between species within and across most sites. Contrastingly, the concentrations of the different herbicides and that of total herbicide did not differ between conspecifics at most sites nested in their respective reef complexes. On average, highest total herbicide concentrations were measured in soft coral (Sarcophyton glaucum; 90.4 ± 60 ng g-1 and Sinularia gravis; 42.7 ± 25 ng g-1) and sponge (Theonela swinhoei; 39.0 ± 40 ng g-1) species, while significantly lower concentrations were detected in hard corals (Echinopora hirsutissima; 10.5 ± 5.9 ng g-1 and Acropora austera; 5.20 ± 4.5 ng g-1) at most sites. Agricultural runoff entering the ocean via the uMfolozi-St Lucia Estuary and Maputo Bay are likely sources of herbicide contamination to coral reefs in the region. There is an urgent need to assess the long-term effects of herbicide exposure on coral reef communities.


Assuntos
Antozoários , Herbicidas , Animais , Recifes de Corais , Ecossistema , Herbicidas/análise , África do Sul , Áreas Alagadas
5.
Chemosphere ; 290: 133216, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34896171

RESUMO

We evaluated the influence of metal accumulation on the oxidative status [lipid peroxidation (LPO) and total antioxidant capacity (TAC)] and carbonic anhydrase (CA) activity in host and symbionts of the coral Mussismilia harttii and the hydrocoral Millepora alcicornis collected in Abrolhos Reef Banks (Northeast Brazil), potentially impacted by a major mine dam rupture. Considering metal levels measured in reefs worldwide, Abrolhos corals had higher Fe and Mn levels than expected for preserved offshore reefs. Increasing concentrations of arsenic (As), chromium (Cr) and manganese (Mn) drove inhibition of CA and increased oxidative damage in the hydrocoral M. alcicornis. The impairment of enzymatic activity in the symbiotic algae of M. alcicornis may be related to the oxidative stress condition. The hydrocoral M. alcicornis was more affected by metals than the coral M. harttii, which did not show the expected CA inhibition after metal exposure. Our results suggest that CA activity can be applied as a complementary biomarker to evaluate the physiological impacts of environmental metal contamination in reefs. Also, the metal levels and biochemical biomarkers reported in the present study may provide reference data to monitor the health of reefs impacted by a relevant dam rupture.


Assuntos
Antozoários , Anidrases Carbônicas , Animais , Oceano Atlântico , Recifes de Corais , Metais/toxicidade , Estresse Oxidativo
6.
Chemosphere ; 286(Pt 2): 131711, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34340115

RESUMO

The levels, fate, and potential sources of 22 organochlorine pesticides (OCPs) in coral tissues and the surrounding air-seawater system from the South China Sea (SCS) were elucidated for the first time. ∑22OCPs (total concentration of 22 OCPs) (16.1-223 pg L-1) was relatively higher in coastal seawater than in offshore seawater, which may be the widespread influence of coastal pollution inputs under the western boundary current. The atmospheric ∑22OCPs were predominantly distributed in the gas phase (48.0-2264 pg m-3) and were mainly influenced by continental air mass origins. The air-seawater exchange of selected OCPs showed that OCPs tended to migrate from the atmosphere to seawater. The distribution of ∑22OCPs in coral tissues (0.02-52.2 ng g-1 dw) was significantly correlated with that in air samples, suggesting that OCPs may have a migration pattern of atmosphere-ocean corals in the SCS. Corals exhibited higher bioaccumulation ability (Log BAFs: 2.42-7.41) for OCPs. Source analysis showed that the new application of technical Chlordanes (CHLs) was primarily responsible for the current levels of CHLs in the surrounding environment over the SCS, while historical residues were the primary sources of other OCPs.


Assuntos
Antozoários , Hidrocarbonetos Clorados , Praguicidas , Animais , China , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Água do Mar
7.
Sci Total Environ ; 806(Pt 2): 150576, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34582873

RESUMO

In the Eastern Tropical Pacific (ETP), Mesophotic Coral Ecosystems (MCEs) are limited by oceanographic conditions and are thought to be mostly absent. However, considering the currently discussed more flexible approach to define mesophotic boundaries, based on light availability, we performed a systematic search to assess their current state of knowledge. Using MODIS-Aqua satellite data (Kd490), we calculated the mesophotic boundaries in the ETP, based on optical depths, and performed a bibliographic search of studies carried out at those depths, including those present in turbid waters with KdPAR values up to 0.2 m-1. Seventy-seven papers on MCEs research were compiled in this review, recording a total of 138 species. The studies focus almost exclusively on taxonomy, ecosystem function, and reviews, indicating the need for future research regarding aspects, such as structuring environmental variables, molecular ecology, and natural resource management. Furthermore, remote sensing data show that there exists a high spatial variability of water transparency in the ETP, resulting in significant differences in KdPAR between oceanic and continental locations, mostly related to the occurrence of seasonal upwelling in the latter. Based on KdPAR, we estimated the mesophotic depth boundaries (z10%, z1%, z0.1%) for specific locations within the ETP and found that MCEs can potentially occur as shallow as 13-15 m in coastal regions. Also, we compared the calculated boundaries with the respective deepest records of light-dependent corals. With one exception, the presence of the corals was restricted to the upper mesophotic subzone (z10%-z1%), which agrees with reports for other regions, showing that light availability is one of the main drivers for the bathymetric distribution of MCEs and can be used as a first approach to identify their potential presence, though other local factors (e.g., geomorphology, temperature, internal waves) should also be considered, as they can cause shifts in depth limits.


Assuntos
Antozoários , Animais , Recifes de Corais , Ecossistema , Temperatura , Água
8.
Sci Total Environ ; 806(Pt 2): 150656, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597574

RESUMO

Coral bleaching has become a major threat to coral reefs worldwide, but for most coral species little is known about their resilience to environmental changes. We aimed to understand the gene expressional regulation underlying natural bleaching and recovery in Pavona decussata, a dominant species of scleractinian coral in the northern South China Sea. Analyzing samples collected in 2017 from the field revealed distinct zooxanthellae density, chlorophyll a concentration and transcriptomic signatures corresponding to changes in health conditions of the coral holobiont. In the host, normal-looking tissues of partially bleached colonies were frontloaded with stress responsive genes, as indicated by upregulation of immune defense, response to endoplasmic reticulum, and oxidative stress genes. Bleaching was characterized by upregulation of apoptosis-related genes which could cause a reduction in algal symbionts, and downregulation of genes involved in stress responses and metabolic processes. The transcription factors stat5b and irf1 played key roles in bleaching by regulating immune and apoptosis pathways. Recovery from bleaching was characterized by enrichment of pathways involved in mitosis, DNA replication, and recombination for tissue repairing, as well as restoration of energy and metabolism. In the symbionts, bleaching corresponded to imbalance in photosystems I and II activities which enhanced oxidative stress and limited energy production and nutrient assimilation. Overall, our study revealed distinct gene expressional profiles and regulation in the different phases of the bleaching and recovery process, and provided new insight into the molecular mechanisms underlying the holobiont's resilience that may determine the species' fate in response to global and regional environmental changes.


Assuntos
Antozoários , Animais , Antozoários/genética , Clorofila A , Recifes de Corais , Folhas de Planta , Simbiose , Transcriptoma
9.
J Environ Manage ; 302(Pt A): 113997, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34710760

RESUMO

When effectively managed, Marine Protected Areas (MPAs) can produce wide ecosystem benefits that can foster, directly and indirectly, local economies. Tourism is one of the sectors mainly benefited by the effect of conservation. SCUBA diving represents an important tourism activity, especially in the context of MPAs, where it is one of the few activities often fostered rather than limited, for its capacity to integrate environmental and socio-economic sustainability. However, SCUBA diving can also produce negative impacts on the environment when tourism frequentation exceeds a sustainable threshold, these potentially generating negative effects on the sector itself. In this study, we (1) investigated the impact of SCUBA diving in one of the most frequented diving areas of the Mediterranean Sea (Cabo de Palos - Islas Hormigas marine reserve), and (2) assessed the potential benefits over time related to the adoption of a regulation change for the diving activity (i.e., formally adoption of diving quotas). Specifically, we compared demographic (density of alive and dead colonies) and morphometric (height, width and complexity) characteristics of the false coral (Myriapora truncata) between dived and fully protected (non-dived) locations over four diving seasons (one before and three after the change in diving quotas). The density of alive colonies of the false coral was, on average, six times lower in dived locations compared to controls, highlighting a clear impact of SCUBA diving (consistent over time). Colonies were also significantly smaller in dived locations. The diving quotas produced a significant reduction of the ratio dead/total colonies in the dived locations soon after their adoption, but these benefits disappeared over the following years, possibly due to a gradual decline in operators' and divers' observance and concern, rather than an increasing number of dives. This suggests that the adoption of effective regulations is crucial for the environmental sustainability of diving tourism in protected areas and can provide positive effects, but an effort is needed to ensure that compliance is consistent over time, and that low-impact diving practices are adopted by this important recreational sector.


Assuntos
Antozoários , Mergulho , Animais , Conservação dos Recursos Naturais , Ecossistema , Mar Mediterrâneo
10.
Sci Total Environ ; 810: 152266, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896508

RESUMO

Ocean acidification (OA) is a pressing issue currently and in the future for coral reefs. The importance of maintenance interactions among partners of the holobiont association in the stress response is well appreciated; however, the candidate molecular and microbial mechanisms that underlie holobiont stress resilience or susceptibility remain unclear. Here, to assess the effects of rapid pH change on coral holobionts at both the protein and microbe levels, combined proteomics and microbiota analyses of the scleractinian coral Galaxea fascicularis exposed to three relevant OA scenarios, including current (pHT = 8.15), preindustrial (pHT = 8.45) and future IPCC-2100 scenarios (pHT = 7.85), were conducted. The results demonstrated that pH changes had no significant effect on the physiological calcification rate of G. fascicularis in a 10-day experiment; however, significant differences were recorded in the proteome and 16S profiling. Proteome variance analysis identified some of the core biological pathways in coral holobionts, including coral host infection and immune defence, and maintaining metabolic compatibility involved in energy homeostasis, nutrient cycling, antibiotic activity and carbon budgets of coral-Symbiodiniaceae interactions were key mechanisms in the early OA stress response. Furthermore, microbiota changes indicate substantial microbial community and functional disturbances in response to OA stress, potentially compromising holobiont health and fitness. Our results may help to elucidate many complex mechanisms to describe scleractinian coral holobiont responses to OA and raise interesting questions for future studies.


Assuntos
Antozoários , Microbiota , Animais , Recifes de Corais , Homeostase , Concentração de Íons de Hidrogênio , Oceanos e Mares , Proteoma , Água do Mar
11.
Sci Total Environ ; 810: 152333, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910947

RESUMO

Coral reefs have been heavily impacted by anthropogenic stressors, such as global warming, ocean acidification, sedimentation, and nutrients. Recently, microplastics (MP) have emerged as another potential stressor that may also cause adverse impacts to coral. MP ingestion by scleractinian coral among four species, Acropora cervicornis, Montastraea cavernosa, Orbicella faveolata, and Pseudodiploria clivosa, was used to identify the relationship between calyx and MP size as it pertains to active coral ingestion. A range of MP sizes (0.231-2.60 mm) were offered to the coral species across a wide range of calyx sizes (1.33-4.84 mm). Laboratory data showed that as the mean calyx size increased, so too did the mean percent of ingestion with increasing MP size. From laboratory data, a logistic model was developed to extrapolate the range of MP sizes that can be actively ingested by coral species based on calyx size. The data and model presented here offer the first predictive approach that can be used to determine the range of MP sizes that have a high likelihood of being actively ingested by coral of various sizes, thus offering insight to possible impacts on scleractinian coral.


Assuntos
Antozoários , Animais , Recifes de Corais , Ingestão de Alimentos , Concentração de Íons de Hidrogênio , Microplásticos , Plásticos/toxicidade , Água do Mar
12.
Sci Total Environ ; 811: 152407, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-34914992

RESUMO

One recent way of reconstructing the historical impact of aboveground nuclear weapons testing (ANWT) in places lacking historical data is by measuring 129I in natural archives such as coral cores. However, discussions arising from 129I in corals remain qualitative or semi-quantitative, which do not maximize the potential information derivable from the data. In this study, we construct a mathematical model that simulates the 129I bomb peaks from the Pacific Proving Grounds (PPG) tests, as observed in available coral core data from the east (Baler) and west (Parola) sides of the Philippines. Results show that the model can determine the expected increase in 129I/127I ratio in the Philippines per megaton of ANWT detonated in the PPG; confirm time lags for each major transport pathway from the PPG to the Philippines, indicating when to expect the radioactivity spike after detonation; and determine the most significant transport pathway from the PPG to each coral location. This work increases the application and significance of 129I/127I coral core data by deriving quantitative information about the magnitude, timing, and transport pathways of radioactivity from the ANWT site to the coral location. In the future, the model can be expanded to simulate other 129I sources besides ANWT.


Assuntos
Antozoários , Armas Nucleares , Monitoramento de Radiação , Poluentes Radioativos da Água , Animais , Recifes de Corais , Radioisótopos do Iodo/análise , Oceano Pacífico , Filipinas , Poluentes Radioativos da Água/análise
13.
J Environ Manage ; 301: 113919, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34731944

RESUMO

Coral bleaching has increasingly impacted reefs worldwide over the past four decades. Despite almost 40 years of research into the mechanistic, physiological, ecological, biophysical and climatic drivers of coral bleaching, metrics to allow comparison between ecological observations and experimental simulations still do not exist. Here we describe a novel metric - experimental Degree Heating Week (eDHW) - with which to standardise the persistently variable thermal conditions employed across experimental studies of coral bleaching by modify the widely used Degree Heating Week (DHW) metric used in ecological studies to standardise cumulative heat loading.


Assuntos
Antozoários , Temperatura Alta , Animais , Recifes de Corais
14.
Sci Total Environ ; 804: 150178, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34798733

RESUMO

Coral reefs are likely to be exposed to more intense cyclones under climate change. Cyclone impacts are spatially highly variable given complex hydrodynamics, and coral-specific sensitivity to wave impacts. Predicting reef vulnerability to cyclones is critical to management but requires high resolution environmental data that are difficult to obtain over broad spatial scales. Using 30m-resolution wave modelling, we tested cyclonic and non-cyclonic wave metrics as predictors of coral damage on 22 reefs after severe cyclone Ita impacted the northern Great Barrier Reef, Australia in 2014. Analyses of coral cover change accounting for the type of coral along a gradient of vulnerability to wave damage (e.g., massive, branching, Acroporids) excluded cyclone-generated surface wave metrics (derived from wave height) as important predictors. Increased bottom stress wave environment (near-bed wave orbital velocity) due to Ita (Ita-Ub) explained spatial patterns of 17% to 46% total coral cover loss only when the initial abundance of Acroporids was accounted for, and only when exceeding 35% cover. Greater coral losses occurred closer to the cyclone path irrespective of coral type. Massive and encrusting corals, however, had losses exacerbated in higher non-cyclonic bottom-wave energy environments (nc-Ub). The effect of community composition on structural vulnerability to wave damage was more important predicting damage that the magnitude of the cyclone-generated waves, especially when reefs are surveyed well beyond where damaging waves are expected to occur. Exposure to Ita-Ub was greater in typically high nc-Ub environments with relatively low cover of the most fragile morphologies explaining why these were the least affected overall. We reveal that the common surface-wave metrics of cyclone intensity may not always be able to predict spatial impacts and conclude that reef vulnerability assessments need to account for chronic wave patterns and differences in community composition in order to provide predictive tools for future conservation and restoration.


Assuntos
Antozoários , Tempestades Ciclônicas , Animais , Benchmarking , Mudança Climática , Recifes de Corais , Ecossistema
15.
Glob Chang Biol ; 28(1): 33-45, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34710272

RESUMO

The pollution of the marine environment with microplastics is pervasive. However, microplastic concentrations in the seawater are lower than the number of particles entering the oceans, suggesting that plastic particles accumulate in environmental sinks. Yet, the exact long-term sinks related to the "missing plastic" phenomenon are barely explored. Sediments in nearshore biogenic habitats are known to trap large amounts of microplastics, but also the three-dimensional structures of coral reefs might serve as unique, living long-term sinks. The main framework builders, reef-building corals, have been shown to ingest and overgrow microplastics, potentially leading to a deposition of particles in reef structures. However, little is known about the number of deposited particles and the underlying processes determining the permanent deposition in the coral skeletons. To test whether corals may act as living long-term sink for microplastic, we exposed four reef-building coral species to polyethylene microplastics (200 particles L-1 ) in an 18-month laboratory experiment. We found microplastics in all treatment specimens, with low numbers of particles trapped in the coral tissue (up to 2 particles per cm2 ) and much higher numbers in the skeleton (up to 84 particles per cm3 ). The numbers of particles accumulated in the coral skeletons were mainly related to coral growth (i.e., skeletal growth in volume), suggesting that deposition is a regularly occurring stochastic process. We estimate that reef-building corals may remove 0.09%-2.82% of the bioavailable microplastics from tropical shallow-reef waters per year. Our study shows for the first time that microplastic particles accumulate permanently in a biological sink, helping to explain the "missing plastic" phenomenon. This highlights the importance of coral reefs for the ecological balance of the oceans and reinforces the need to protect them, not only to mitigate the effects of climate change but also to preserve their ecosystem services as long-term sink for microplastic.


Assuntos
Antozoários , Microplásticos , Animais , Recifes de Corais , Ecossistema , Plásticos
16.
Cells ; 10(12)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34944043

RESUMO

Polysaccharides from marine organisms produce an important regulatory effect on the mammalian immune system. In this study, the immunomodulatory properties of a polysaccharide that was isolated from the coral Pseudopterogorgia americana (PPA) were investigated. PPA increased the expression levels of tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2), but not inducible nitric oxide synthase and nitric oxide, in macrophages. A mechanistic study revealed that PPA activated macrophages through the toll-like receptor-4 and induced the generation of reactive oxygen species (ROS), increased the phosphorylation levels of protein kinase C (PKC)-α, PKC-δ and mitogen-activated protein kinases (MAPK), and activated NF-κB. The inhibition of ROS and knockdown of PKC-α reduced PPA-mediated TNF-α and IL-6 expression; however, the knockdown of PKC-δ significantly increased PPA-mediated TNF-α expression. In addition, the inhibition of c-Jun N-terminal kinase-1/2 and NF-κB reduced PPA-mediated TNF-α, IL-6 and COX-2 expression. Furthermore, the inhibition of ROS, MAPK and PKC-α/δ reduced PPA-mediated NF-κB activation, indicating that ROS, MAPK and PKC-α/δ function as upstream signals of NF-κB. Finally, PPA treatment decreased the phagocytosis activity of macrophages and reduced cytokine expression in bacteria-infected macrophages. Taken together, our current findings suggest that PPA can potentially play a role in the development of immune modulators in the future.


Assuntos
Antozoários/química , Fatores Imunológicos/farmacologia , Macrófagos/imunologia , Polissacarídeos/farmacologia , Animais , Ciclo-Oxigenase 2/metabolismo , Citocinas/biossíntese , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Fagocitose/efeitos dos fármacos , Polissacarídeos/química , Proteína Quinase C-alfa/metabolismo , Proteína Quinase C-delta/metabolismo , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Células THP-1 , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
17.
PLoS One ; 16(12): e0258725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34910721

RESUMO

Small cryptic invertebrates (the cryptofauna) are extremely abundant, ecologically important, and species rich on coral reefs. Ongoing ocean acidification is likely to have both direct effects on the biology of these organisms, as well as indirect effects through cascading impacts on their habitats and trophic relationships. Naturally acidified habitats have been important model systems for studying these complex interactions because entire communities that are adapted to these environmental conditions can be analyzed. However, few studies have examined the cryptofauna because they are difficult to census quantitatively in topographically complex habitats and are challenging to identify. We addressed these challenges by using Autonomous Reef Monitoring Structures (ARMS) for sampling reef-dwelling invertebrates >2 mm in size and by using DNA barcoding for taxonomic identifications. The study took place in Papua New Guinea at two reef localities, each with three sites at varying distances from carbon dioxide seeps, thereby sampling across a natural gradient in acidification. We observed sharp overall declines in both the abundance (34-56%) and diversity (42-45%) of organisms in ARMS under the lowest pH conditions sampled (7.64-7.75). However, the overall abundance of gastropods increased slightly in lower pH conditions, and crustacean and gastropod families exhibited varying patterns. There was also variability in response between the two localities, despite their close proximity, as one control pH site displayed unusually low diversity and abundances for all invertebrate groups. The data illustrate the complexity of responses of the reef fauna to pH conditions, and the role of additional factors that influence the diversity and abundance of cryptic reef invertebrates.


Assuntos
Antozoários , Biodiversidade , Dióxido de Carbono/análise , Crustáceos , Gastrópodes , Água do Mar/análise , Animais , Antozoários/classificação , Antozoários/genética , Antozoários/crescimento & desenvolvimento , Recifes de Corais , Crustáceos/classificação , Crustáceos/genética , Crustáceos/crescimento & desenvolvimento , Código de Barras de DNA Taxonômico , Gastrópodes/classificação , Gastrópodes/genética , Gastrópodes/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Papua Nova Guiné
18.
Nat Commun ; 12(1): 7282, 2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34907163

RESUMO

Ecosystems face both local hazards, such as over-exploitation, and global hazards, such as climate change. Since the impact of local hazards attenuates with distance from humans, local extinction risk should decrease with remoteness, making faraway areas safe havens for biodiversity. However, isolation and reduced anthropogenic disturbance may increase ecological specialization in remote communities, and hence their vulnerability to secondary effects of diversity loss propagating through networks of interacting species. We show this to be true for reef fish communities across the globe. An increase in fish-coral dependency with the distance of coral reefs from human settlements, paired with the far-reaching impacts of global hazards, increases the risk of fish species loss, counteracting the benefits of remoteness. Hotspots of fish risk from fish-coral dependency are distinct from those caused by direct human impacts, increasing the number of risk hotspots by ~30% globally. These findings might apply to other ecosystems on Earth and depict a world where no place, no matter how remote, is safe for biodiversity, calling for a reconsideration of global conservation priorities.


Assuntos
Antozoários/fisiologia , Recifes de Corais , Peixes/fisiologia , Animais , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais , Humanos , Análise Espacial
19.
J Nanosci Nanotechnol ; 21(6): 3312-3319, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34739787

RESUMO

Coral reefs are cornerstone of global marine ecosystems, providing shelter for over one third of marine organisms. Currently, along with global warming and increased human activities, large-scale decline of coral reefs has become a severe ecosystem problem, and now quantitative detection of heat shock protein (HSP) gene by nanotechnology has become a research hotspot in this field. However, Acropora muricata is one of the most important dominant reef-building corals in Indo- Pacific region, encounter an urgent obstacle on the HSP detection research by nanoscience and nanotechnology for lack of sequence background. Here, we combined PacBio single molecular real-time (SMRT) and HiSeq X Ten sequencing technologies to perform full-length transcriptome sequencing of heat shock proteins in Acropora muricata, a reef-building coral dominant in many Indo-Pacific reefs, to annotate them. Thirteen functional heat shock proteins (HSPs) were identified using phylogenetic analysis, classified into three subgroups as HSP60, HSP70 and HSP90. HSPs are widely distributed in all animal phyla, having evolved from the last prokaryotic common ancestor. Additionally, phylogenetic and tertiary nanostructure analyses suggested that HSP70 is the most diverse HSP in A. muricata, with extensive sequence and structure differences indicating adaptations to warming water and suggesting its utility in studies of El Niño and other warming events. A greater understanding of the HSP gene family is likely to also be of value in studies of coral nanotechnological detection that can be used to protect reef ecosystems.


Assuntos
Antozoários , Animais , Antozoários/genética , Ecossistema , Proteínas de Choque Térmico , Humanos , Nanotecnologia , Filogenia
20.
Zootaxa ; 4999(5): 401-422, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34811337

RESUMO

Five new species of deep-sea antipatharian corals are described from the North Pacific primarily collected off the coast of Alaska and on adjacent seamounts. All the species are referred to the family Schizopathidae. Described as new are: Alternatipathes mirabilis, Bathypathes ptiloides, Bathypathes tiburonae, Bathypathes alaskensis, and Parantipathes pluma. Illustrations of the type material of Bathypathes patula, B. patula var. plenispina and B. tenuis are provided for comparative proposes. Bathypathes patula var. plenispina is here recognized as a species distinct from B. patula, and B. tenuis is considered incertae sedis due to the poor condition of the type material.


Assuntos
Antozoários , Mirabilis , Animais
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