Portugal nautical stations: Strategic alliances for sport tourism and environmental sustainability.

Nautical tourism is a tourist product with great development in the European space and a lot of potential to promote and develop tourist destinations. Considering the dynamics of nautical tourism management and the importance of meeting the specificities of this market niche, the objective of this study was to analyse the strategic alliances for the development of the offer of nautical tourism products, namely the strategic goals and sustainable environmental practices adopted by their actors which integrated the strategic alliances in order to certificate a plethora of nautical stations in Portugal. Between September and December 2021, 17 Portuguese nautical stations' application forms were collected. Content analysis using Nvivo software was the technique used for data analysis. The results showed a multiplicity of strategic objectives associated with the strategic alliance established between the nautical stations. The strategic vision of nautical stations for the development of strategic alliances is built, firstly, on the objective of structuring the tourism offer, followed by increasing governance and promoting and marketing nautical tourism using the image of the destination. Based on these results, it is possible to infer the importance of nautical stations in destination competitiveness and the role of strategic alliances in facilitating penetration in the nautical tourism market. The managers of nautical stations should consider the use of strategic alliances to make a cooperative marketing in order to improve the experience of the clients. Regarding environmental sustainability practices, the results exposed the prominence of environmental education actions in contrast to the reduced number of nautical stations developing actions for the adoption of sustainable transport. This study contributes to a better understanding of nautical tourism and Portuguese nautical stations, a project of strategic investment in sport and tourism, inferring on the objectives underlying the formation of strategic alliances and on the adopted environmental sustainability practices. The conclusions of this study point to the need for future scientific research on the actual operationalization of the objectives underlying the formation of strategic alliances, as well as the environmental practices developed by nautical stations.

Glutaric Aciduria Type 2 Presenting in Adult Life With Hypoglycemia and Encephalopathic Hyperammonemia.

Glutaric aciduria type 2 is a rare inborn disease of fatty acid metabolism. The clinical manifestation of this disease is heterogeneous and ranges from severe neonatal forms to mild late-onset forms. We present a case of a previously healthy 22-year-old woman with unexplainable hypoglycemia and encephalopathic hyperammonemia. Acylcarnitine profile and organic acids analysis were compatible with glutaric aciduria type 2. On suspicion of this disease, the patient started supplements with carnitine and riboflavin, along with hemodialysis with a complete recovery. The genetic test confirmed the diagnosis. Glutaric aciduria type 2 has no cure and the metabolic decompensation can be a severe event, but treatable and preventable, if this pathology gets recognized.

Hunter Syndrome: The Phenotype of a Rare Storage Disease.

Hunter syndrome is a rare lysosomal storage disorder with systemic involvement that occurs over time. Affected patients have coarse facial features, growth retardation with short stature, and skeletal deformities called dysostosis multiplex; joint stiffness, progressive mental retardation, and organomegaly are some of the clinical signs. It ranges from mild to severe manifestations and the distinction between them is related to neurological involvement. Cardiac and respiratory failure is commonly the cause of early death (before adulthood) for severe forms, but those with attenuated forms who have normal cognitive development can survive until late adulthood. Treatment with enzyme replacement therapy is available and can improve the prognosis of this disease. The authors present a case of a 36-year-old male with Hunter syndrome to show not only the clinical features typical of this multisystemic disease that should alert to a prompt investigation but also to remind that treatment must start as early as possible to reach the best outcome. Management of this disease is typically challenging and requires a multidisciplinary approach.

Niemann-Pick Type B: A Rare Cause of Interstitial Lung Disease.

Niemann-Pick disease (NPD) is a rare lysosomal storage disease (LSD) with multisystemic involvement. The disease is heterogeneous and classified into three subtypes: type A and B result from deficient acid sphingomyelinase activity and leads to the accumulation of sphingomyelin and type C is a genetically different disease resulting from defective intracellular trafficking of cholesterol with accumulation of glycosphingolipids. Type A is generally a neurodegenerative disease and is fatal in infancy. Type B is a less severe form characterized by pulmonary involvement, hepatosplenomegaly, hyperlipidemia and most patients live into adulthood. In type C, clinical presentation is dominated with neurological involvement. Pulmonary involvement occurs in all three types of Niemann-Pick but most frequently in type B. Clinical manifestations range from a lack of symptoms to respiratory failure, and respiratory symptoms are usually mild with recurrent cough, dyspnoea on exertion and recurrent respiratory infections. Interstitial lung disease (ILD) is the most prominent feature with slow progression, characterized by worsening pulmonary function tests. In recent years, enzyme replacement therapy has shown promising results in clinical trials, such as improvement in organomegaly and pulmonary involvement with the potential to improve patients' lives. We present three cases of NPD with pulmonary involvement, each exhibiting a different pattern of ILD and evaluate therapeutic options.

Galanin and prolactin expression in relation to parental care in two sympatric cichlid species from Lake Tanganyika.

Our understanding of the hormonal mechanisms underlying parental care mainly stems from research on species with uniparental care. Far less is known about the physiological changes underlying motherhood and fatherhood in biparental caring species. Here, using two biparental caring cichlid species (Neolamprologus caudopunctatus and Neolamprologus pulcher), we explored the relative gene-expression levels of two genes implicated in the control of parental care, galanin (gal) and prolactin (prl). We investigated whole brain gene expression levels in both, male and female caring parents, as well as in non-caring individuals of both species. Caring males had higher prl and gal mRNA levels compared to caring females in both fish species. Expression of gal was highest when young were mobile and the need for parental defense was greatest and gal was lowest during the more stationary egg tending phase in N. caudopunctatus. The onset of parenthood was associated with lower expression of prl and higher expression of gal in N. pulcher, but this pattern was not observed in N. caudopunctatus. Our study demonstrates that gal gene expression is correlated with changes in parental care in two biparental cichlid species and extends both knowledge and taxonomic coverage of the possible neurogenetic mechanisms underlying parental care.

Galanin isoforms by alternative splicing: Structure, expression, and immunohistochemical location in the gonads of European sea bass.

Galanin (Gal) is a neuropeptide with multiple functions that is widely expressed in the central and peripheral nervous systems of vertebrates. Anatomical and functional evidence suggests a possible role in regulating reproduction in fishes. To test this possibility, we have isolated and characterized two gal alternative transcripts in European sea bass (Dicentrarchus labrax) that encode two prepropeptides, respectively of 29 (gal_MT853221) and 53 (gal_MT853222) amino acids. The two gal transcripts are highly expressed in brain, pituitary and gonads, and appear to be differentially regulated in males and females. In males, gal_MT853222 in the hypothalamus and gal_MT853221 in the pituitary were downregulated with the progression of spermatogenesis (stages I-III). Both transcripts are downregulated in testicles of 1-year (precocious) and 2-year spermiating males compared to immature fish of the same age. Gal peptides and receptors are expressed throughout ovarian development in the hypothalamic-pituitary-gonadal (HPG) axis of females. In the testis, immunoreactive Gal-29 and Gal-53 peptides were detected in blood vessels and Leydig cells during the spermatogenesis stages I-III but Gal immunostaining was barely undetected in more advanced stages. In the ovary, both peptides localized in interstitial cells and blood vessels and in theca cells surrounding the maturing oocytes. The immunolocalization of galanin in Leydig and theca cells suggests a possible role in steroid production regulation. The different pattern of gal expression and Gal localization in the testis and ovary may suggest the possibility that androgens and estrogens may also regulate Gal gene transcription and translation. Altogether, this study showed evidence for the possible involvement of locally produced Gal in gametogenesis and that its production is differentially regulated in male and female gonads.

Miniaturized Fluorimetric Method for Quantification of Zinc in Dry Dog Food.

Zinc is an essential trace element for animals in several biological processes, particularly in energy production, and it is acquired from food ingestion. In this context, a microplate-based fluorimetric assay was developed for simple, fast, and low-cost determination of zinc in pet food using 2,2'-((4-(2,7-difluoro-3,6-dihydroxy-4aH-xanthen-9-yl)-3-methoxyphenyl)azanediyl)diacetic acid (FluoZin-1) as fluorescent probe. Several aspects were studied, namely, the stability of the fluorescent product over time, the FluoZin-1 concentration, and the pH of reaction media. The developed methodology provided a limit of detection of 1 µg L-1 in sample acid digests, with a working range of 10 to 200 µg L-1, corresponding to 100-2000 mg of Zn per kg of dry dog food samples. Intraday repeatability and interday repeatability were assessed, with relative standard deviation values < 3.4% (100 µg L-1) and <11.7% (10 µg L-1). Sample analysis indicated that the proposed fluorimetric assay provided results consistent with ICP-MS analysis. These results demonstrated that the developed assay can be used for rapid determination of zinc in dry dog food.

Primary Aortoesophageal Fistula: Is a High Level of Suspicion Enough?

Aortoenteric fistula (AEF) is a rare condition with a high mortality rate. AEFs are classified according to their primary and secondary causes, the former being less frequent. Primary AEFs occur in a native aorta and their causes include aneurysms, foreign bodies, tumours, radiotherapy and infection. The classic triad of aortoesophageal fistulas, a subtype of AEFs, are mid-thoracic pain and sentinel haemorrhage, followed by massive bleeding after a symptom-free interval. We present the case of a 41-year-old male patient who presented in the emergency room after successive episodes of abundant haematemesis. He was hypovolemic, hypothermic and acidotic at presentation. His medical history included an emergency room visit the week before with chest pain but no relevant anomalies on work-up, active intravenous drug use and chronic hepatitis. Esophagogastroduodenoscopy (EGD) showed a bulging ulcerated lesion suspicious for aortoesophageal fistula, confirmed by computed tomography (CT) angiography, which revealed a saccular aortic aneurysm with a bleeding aortoesophageal fistula. The patient underwent urgent thoracic endovascular aortic repair. The sentinel chest pain, leucocytosis and CT findings hinted at the presence of a mycotic aneurysm, despite the negative blood cultures. It was most likely caused by a septic embolus due to the patient's risk factors. While a high level of suspicion for aortoesophageal fistula is needed to prompt a fast diagnosis, EGD and CT findings were crucial to establish it and allow a life-saving intervention. We conclude that chest pain cannot be disregarded in a patient aged 41 years with multiple comorbidities, despite normal work-up, to prevent a fatal outcome. LEARNING POINTS: Aortoesophageal fistula is a rare cause of severe upper gastrointestinal haemorrhage with a high mortality rate.Computed tomography angiography is diagnostic in most cases but a high level of suspicion is essential.Chest pain, a characteristic clinical symptom of aortoesophageal fistula, cannot be disregarded in a patient with multiple comorbidities, even in the presence of a normal electrocardiogram and chest x-ray.

Appropriateness of Radiology Test Requests by an Emergency Department: A Retrospective Study.

INTRODUCTION: Imaging tests are essential for diagnosis in the emergency context and convey clinical information that is essential to assess the appropriateness of the tests and improve their interpretation. Therefore, we aimed to analyze the imaging tests requested by the Emergency Department in a district hospital. MATERIAL AND METHODS: We retrospectively analyzed computed tomography and ultrasound scans requested by the Emergency Department at the Centro Hospitalar Universitário do Algarve and considered the following variables: requested test, clinical information provided (complete/incomplete), appropriateness of the test (appropriate/inappropriate), outcome (presence/absence of relevant findings) and findings related to the clinical information (yes/no). Pearson's chi-squared and odds ratio association tests were used to evaluate the statistical association between the variables. RESULTS: Out of 1427 requests, only 219 (15.3%) were considered to have complete clinical information. Nonetheless, 1075 (75.3%) requests were considered appropriate. Relevant findings were present in about one-third (n = 453; 31.7%) and most of these findings were related to the clinical context (n = 410; 90.5%). There was a significant association between test appropriateness and the presence of relevant findings in the test (p < 0.001). The odds ratio of having a relevant finding was 5.0 times higher in the tests considered appropriate when compared with those classified as inappropriate (CI = 3.4 - 7.3; p < 0.001). DISCUSSION: The fact that appropriate tests potentiate the probability of having a relevant finding emphasizes the importance of defining guidelines so that only the adequate tests are performed. CONCLUSION: Creating guidelines should improve the appropriateness of imaging tests requested in the Emergency Department, yielding their result, with the consequent rationalization of the available resources.

Introdução: Os exames de imagem são essenciais para o diagnóstico em contexto de emergência, sendo a informação clínica determinante para verificar a sua adequação e melhorar a sua interpretação. O nosso objetivo compreendeu a análise dos exames de imagem requisitados pelo Departamento de Emergência num hospital distrital. Material e Métodos: Realizámos uma análise retrospetiva das tomografias computorizadas e ecografias requeridas pelo Departamento de Emergência no Centro Hospitalar Universitário do Algarve considerando as seguintes variáveis: exame requisitado, informação clínica fornecida (completa/incompleta), adequação do exame (adequado/não adequado), resultado (presença/ausência de achados relevantes) e relação dos achados com contexto clínico (relacionados/não relacionados). A associação entre variáveis foi avaliada utilizando as análises qui-quadrado de Pearson e razão de possibilidades. Resultados: Das 1427 requisições, apenas 219 (15,3%) foram consideradas como contendo informação clínica completa. No entanto, 1075 (75,3%) requisições foram consideradas adequadas. Cerca de um terço dos exames continha achados relevantes (n = 453; 31,7%) e a maioria destes achados estavam relacionados com o contexto clínico (n = 410; 90,5%). Encontrámos associações significativas entre a adequação do pedido e presença de achados clínicos relevantes (p < 0,001). A razão de possibilidades de ter um achado relevante é 5,0 vezes maior nos pedidos adequados relativamente aos não adequados (IC = 3,4 - 7,3; p < 0,001). Discussão: O facto de os exames adequados potenciarem a probabilidade de existir um achado relevante enfatiza a importância da definição de diretrizes para que só os exames adequados sejam realizados. Conclusão: A criação destas diretrizes deverá aumentar a adequação dos exames de imagem solicitados no Departamento de Emergência, otimizando o seu resultado, com a consequente racionalização dos recursos disponíveis.

Interaction between HFE and haptoglobin polymorphisms and its relation with plasma glutathione levels in obese children.

Obesity among children has emerged as a serious public health problem. The growing prevalence of childhood obesity has led to the appearance of serious complications, including a chronic systemic inflammation associated with oxidative stress.  In the present study, we analysed the interaction between two genes related with iron metabolism - HFE and haptoglobin - and the plasmatic concentration of glutathione, as a way to evaluate the antioxidant response capacity in obesity. To achieve this, 118 obese children and 89 eutrophic children were recruited for the study. Results showed that although obese children present a significantly decreased tGSH levels, once we analysed separately children based on their haptoglobin phenotype, the decreased tGSH levels is significant only for the Hp 2 allele. Additionally, Hp 2.2 obese children carrying H63D polymorphism show significantly lower tGSH/GSSG values. Our results found an association of haptoglobin and HFE with oxidative stress in childhood obesity.

Modulation of aquaporin gene expression by n-3 long-chain PUFA lipid structures in white and brown adipose tissue from hamsters.

EPA (20 : 5n-3) and DHA (22 : 6n-3) fatty acids have weight-reducing properties with physiological activity depending on their molecular structure - that is, as TAG or ethyl esters (EE). Aquaporins (AQP) are membrane protein channels recognised as important players in fat metabolism, but their differential expression in white adipose tissue (WAT) and brown adipose tissue (BAT), as well as their modulation by dietary n-3 long-chain PUFA (LCPUFA) such as EPA and DHA, has never been investigated. In this study, the transcriptional profiles of AQP3, AQP5, AQP7 and selected lipid markers of WAT (subcutaneous and visceral) and BAT (interscapular) from hamsters fed diets containing n-3 LCPUFA in different lipid structures such as fish oil (FO, rich in EPA and DHA in the TAG form) and FO-EE (rich in EPA and DHA in the EE form) were used and compared with linseed oil (LSO) as the reference group. A clear effect of fat depot was observed for AQP3 and leptin (LEP), with the lowest values of mRNA found in BAT relative to WAT. The opposite occurred for PPARα. AQP7 was affected by diet, with FO-fed hamsters having higher mRNA levels compared with LSO-fed hamsters. The relative gene expression of AQP5, adiponectin (ADIPO), GLUT4 and PPARγ was influenced by both fat tissue and diet. Taken together, our results revealed a differential expression profile of AQP and some markers of lipid metabolism in both WAT and BAT in response to feeding n-3 LCPUFA in two different structural formats: TAG v. EE.

Temperature responsiveness of gilthead sea bream bone; an in vitro and in vivo approach.

This study aimed to characterize the molecules involved in osteogenesis in seabream and establish using in vitro/in vivo approaches the responsiveness of selected key genes to temperature. The impact of a temperature drop from 23 to 13 °C was evaluated in juvenile fish thermally imprinted during embryogenesis. Both, in vitro/in vivo, Fib1a, appeared important in the first stages of bone formation, and Col1A1, ON and OP, in regulating matrix production and mineralization. OCN mRNA levels were up-regulated in the final larval stages when mineralization was more intense. Moreover, temperature-dependent differential gene expression was observed, with lower transcript levels in the larvae at 18 °C relative to those at 22 °C, suggesting bone formation was enhanced in the latter group. Results revealed that thermal imprinting affected the long-term regulation of osteogenesis. Specifically, juveniles under the low and low-to-high-temperature regimes had reduced levels of OCN when challenged, indicative of impaired bone development. In contrast, gene expression in fish from the high and high-to-low-temperature treatments was unchanged, suggesting imprinting may have a protective effect. Overall, the present study revealed that thermal imprinting modulates bone development in seabream larvae, and demonstrated the utility of the in vitro MSC culture as a reliable tool to investigate fish osteogenesis.

Sleep health assessment: A scale validation.

Sleep health is a new and important concept. Considering the need to expand the research on sleep from the health perspective, this research proposes to validate a Sleep Health Scale (SHS) for use with the Portuguese adult population. A sample of 540 community-dwelling adults aged 18-90 years old was included. The SHS scores ranged from 0 to 30 with a mean of 19.09 (SD ± 6.49). The distribution indicated that all socio demographic variables (age, gender, and literacy) influenced sleep health. Exploratory factor analysis (EFA) demonstrated one factor for this measurement model with poor indices (Chi-square (df) = 55.02(9), p < 0.001). Confirmatory factor analysis (CFA) was performed on the single factor and showed a well-adjusted model except for question 5 (Chi-square (df) = 11.443(4), p = 0.022; RMSEA = 0.084; CFI=0.99; GFI = 0.98; AGFI = 0.94), the convergent validity (AVE = 0.55) and reliability values (α = 0.85 /CR = 0.86) were good. In conclusion, the Sleep Health Scale (SHS) is valid and reliable for the assessment of the several sleep health indicators of Portuguese adults. An investigation on the relationship between sleep health and well-being in promoting quality of life with this scale is recommended for future research.

Depression and sleep quality in older adults: a meta-analysis.

The literature emphasizes depression and poor sleep quality as problems that affect many elderly individuals. However, these problems have been related in few studies and there is no meta-analysis performed so far on this relationship. The present research reviewed the studies performed on the subjective sleep quality in order to understand how it relates to depression in older adults. The review was conducted in January 2016 and comprised publications between 2005 and 2015. Based on the electronic databases Web of Science and EBSCO, we used the keywords 'sleep quality', 'depression', and 'older' to identify the empirical studies performed. After assessing the collected studies, we selected those that presented the elderly as participants, resulting in nine papers (N = 3069). A random-effects method was used to evaluate the relationship between depression and sleep. We found that an older person's lack of good sleep quality is significantly related with depression. The main limitation of this study was the difficulty in collecting a greater number of studies. Future research should consider the importance of additional variables (e.g. moderators) in order to understand and investigate viable interventions for prevention and health promotion in the elderly.

Validation of the Portuguese version of the Pittsburgh Sleep Quality Index (PSQI-PT).

The present study was realised to validate the Portuguese version of the PSQI. The instrument PSQI-PT was applied to 347 Portuguese community-dwelling adults aged 18-69 years old. The resulting data was used to perform the psychometric analysis to validate the instrument. No structural modifications to the questionnaire were necessary during the adaptation process. The scores for the PSQI-PT showed an adequate internal consistency. The principal component analysis (PCA) produced good factor loading for all items. Finally, the analysis of demographic variables showed that age and literacy influence the values for the "Global Sleep Quality" (GSQ) in this Portuguese sample. In conclusion, this study demonstrated that the PSQI-PT is a valid and reliable instrument for the assessment of sleep quality with the advantage of allowing community-dwelling adults differentiation between good and poor sleepers.

Novel hydroxyamides and amides containing D-glucopyranose or D-fructose units: Biological assays in MCF-7 and MDST8 cell lines.

A novel library of 15 compounds, hydroxyamides and amides containing a ß-D-glucopyranose (D-Gluc) or a ß-D-fructose (D-Fruc) units was designed and synthesized for antiproliferative assays in breast (MCF-7) and colon (MDST8) cancer cell lines. Twelve of them were hydroxyamides and were successfully synthesized from ß-D-glucuronic acid (D-GluA). Six of these hydroxyamides which were acetylated hydroxy-ß-D-glucopyranuronamide 2a-2f (1st Family) and the other six were their respective isomers, that is, hydroxy-ß-D-fructuronamide 3a-3f (2nd Family), obtained by acid-base catalyzed isomerization. These compounds have the general structure, D-Gluc-C=ONH-CHR-(CH2)n-OH and D-Fruc-C=ONH-CHR-(CH2)n-OH, where R=an aromatic, alkyl or a hydrogen substituent, with n=0 or 1. Eight of these contained a chiral aminoalcohol group. Three compounds were amides containing a D-glucopyranose unit (3rd Family). SAR studies were conducted with these compounds. Antiproliferative studies showed that compound 4a, the bromo-amide containing the ß-D-glucopyranose ring, potently inhibits the proliferation of the MDST8 cells. Five compounds (2e, 2f, 3d, 3e, and 3f) were shown to potently selectively inhibit the proliferation of the MCF-7 cells. Compound 4b was the only one showing inhibition in both cell lines. In general, the more active compounds were the amides and hydroxyamides containing the ß-D-fructose moiety, and containing an alkyl group or hydrogen. Half-inhibitory concentrations (IC50) of between 0.01 and 10 µM, were observed.

Long live FOXO: unraveling the role of FOXO proteins in aging and longevity.

Aging constitutes the key risk factor for age-related diseases such as cancer and cardiovascular and neurodegenerative disorders. Human longevity and healthy aging are complex phenotypes influenced by both environmental and genetic factors. The fact that genetic contribution to lifespan strongly increases with greater age provides basis for research on which "protective genes" are carried by long-lived individuals. Studies have consistently revealed FOXO (Forkhead box O) transcription factors as important determinants in aging and longevity. FOXO proteins represent a subfamily of transcription factors conserved from Caenorhabditis elegans to mammals that act as key regulators of longevity downstream of insulin and insulin-like growth factor signaling. Invertebrate genomes have one FOXO gene, while mammals have four FOXO genes: FOXO1, FOXO3, FOXO4, and FOXO6. In mammals, this subfamily is involved in a wide range of crucial cellular processes regulating stress resistance, metabolism, cell cycle arrest, and apoptosis. Their role in longevity determination is complex and remains to be fully elucidated. Throughout this review, the mechanisms by which FOXO factors contribute to longevity will be discussed in diverse animal models, from Hydra to mammals. Moreover, compelling evidence of FOXOs as contributors for extreme longevity and health span in humans will be addressed.

Photoperiodic Modulation of Circadian Clock and Reproductive Axis Gene Expression in the Pre-Pubertal European Sea Bass Brain.

The acquisition of reproductive competence requires the activation of the brain-pituitary-gonad (BPG) axis, which in most vertebrates, including fishes, is initiated by changes in photoperiod. In the European sea bass long-term exposure to continuous light (LL) alters the rhythm of reproductive hormones, delays spermatogenesis and reduces the incidence of precocious males. In contrast, an early shift from long to short photoperiod (AP) accelerates spermatogenesis. However, how photoperiod affects key genes in the brain to trigger the onset of puberty is still largely unknown. Here, we investigated if the integration of the light stimulus by clock proteins is sufficient to activate key genes that trigger the BPG axis in the European sea bass. We found that the clock genes clock, npas2, bmal1 and the BPG genes gnrh, kiss and kissr share conserved transcription factor frameworks in their promoters, suggesting co-regulation. Other gene promoters of the BGP axis were also predicted to be co-regulated by the same frameworks. Co-regulation was confirmed through gene expression analysis of brains from males exposed to LL or AP photoperiod compared to natural conditions: LL fish had suppressed gnrh1, kiss2, galr1b and esr1, while AP fish had stimulated npas2, gnrh1, gnrh2, kiss2, kiss1rb and galr1b compared to NP. It is concluded that fish exposed to different photoperiods present significant expression differences in some clock and reproductive axis related genes well before the first detectable endocrine and morphological responses of the BPG axis.

Unravelling the Evolution of the Allatostatin-Type A, KISS and Galanin Peptide-Receptor Gene Families in Bilaterians: Insights from Anopheles Mosquitoes.

UNLABELLED: Allatostatin type A receptors (AST-ARs) are a group of G-protein coupled receptors activated by members of the FGL-amide (AST-A) peptide family that inhibit food intake and development in arthropods. Despite their physiological importance the evolution of the AST-A system is poorly described and relatively few receptors have been isolated and functionally characterised in insects. The present study provides a comprehensive analysis of the origin and comparative evolution of the AST-A system. To determine how evolution and feeding modified the function of AST-AR the duplicate receptors in Anopheles mosquitoes, were characterised. Phylogeny and gene synteny suggested that invertebrate AST-A receptors and peptide genes shared a common evolutionary origin with KISS/GAL receptors and ligands. AST-ARs and KISSR emerged from a common gene ancestor after the divergence of GALRs in the bilaterian genome. In arthropods, the AST-A system evolved through lineage-specific events and the maintenance of two receptors in the flies and mosquitoes (Diptera) was the result of a gene duplication event. Speciation of Anopheles mosquitoes affected receptor gene organisation and characterisation of AST-AR duplicates (GPRALS1 and 2) revealed that in common with other insects, the mosquito receptors were activated by insect AST-A peptides and the iCa2+-signalling pathway was stimulated. GPRALS1 and 2 were expressed mainly in mosquito midgut and ovaries and transcript abundance of both receptors was modified by feeding. A blood meal strongly up-regulated expression of both GPRALS in the midgut (p < 0.05) compared to glucose fed females. Based on the results we hypothesise that the AST-A system in insects shared a common origin with the vertebrate KISS system and may also share a common function as an integrator of metabolism and reproduction. HIGHLIGHTS: AST-A and KISS/GAL receptors and ligands shared common ancestry prior to the protostome-deuterostome divergence. Phylogeny and gene synteny revealed that AST-AR and KISSR emerged after GALR gene divergence. AST-AR genes were present in the hemichordates but were lost from the chordates. In protostomes, AST-ARs persisted and evolved through lineage-specific events and duplicated in the arthropod radiation. Diptera acquired and maintained functionally divergent duplicate AST-AR genes.

PACAP system evolution and its role in melanophore function in teleost fish skin.

Pituitary adenylate cyclase-activating polypeptide (PACAP) administered to tilapia melanophores ex-vivo causes significant pigment aggregation and this is a newly identified function for this peptide in fish. The G-protein coupled receptors (GPCRs), adcyap1r1a (encoding Pac1a) and vipr2a (encoding Vpac2a), are the only receptors in melanophores with appreciable levels of expression and are significantly (p < 0.05) down-regulated in the absence of light. Vpac2a is activated exclusively by peptide histidine isoleucine (PHI), which suggests that Pac1a mediates the melanin aggregating effect of PACAP on melanophores. Paradoxically activation of Pac1a with PACAP caused a rise in cAMP, which in fish melanophores is associated with melanin dispersion. We hypothesise that the duplicate adcyap1ra and vipr2a genes in teleosts have acquired a specific role in skin and that the melanin aggregating effect of PACAP results from the interaction of Pac1a with Ramp that attenuates cAMP-dependent PKA activity and favours the Ca(2+)/Calmodulin dependent pathway.