Characterisation and expression analysis of cathepsins and ubiquitin-proteasome genes in gilthead sea bream (Sparus aurata) skeletal muscle

The proteolytic enzymes involved in normal protein turnover in fish muscle are also responsible for post-mortem softening of the flesh and are therefore potential determinants of product quality. The main enzyme systems involved are calpains, cathepsins, and the ubiquitin-proteasome (UbP). In this study on Sparus aurata (Sa), the coding sequences of cathepsins (SaCTSB and SaCTSDb) and UbP family members (SaN3 and SaUb) were cloned from fast skeletal muscle, and their expression patterns were examined during ontogeny and in a fasting/re-feeding experiment. The amino acid sequences identified shared 66-100% overall identity with their orthologues in other vertebrates, with well conserved characteristic functional domains and catalytic residues. SaCTSDb showed phylogenetic, sequence and tissue distribution differences with respect to its paralogue SaCTSDa, previously identified in the ovary. Expression of gilthead sea bream cathepsins (B, L, Da, Db) and UbP members (N3, Ub, MuRF1 and MAFbx) in fast skeletal muscle was determined at three different life-history stages and in response to fasting and re-feeding in juveniles. Most of the proteolytic genes analysed were significantly up-regulated during fasting, and down-regulated with re-feeding and, between the fingerling (15 g) and juvenile/adult stages (~50/500 g), consistent with a decrease in muscle proteolysis in both later contexts. In contrast, SaCTSDa and SaMuRF1 expression was relatively stable with ontogeny and SaUb had higher expression in fingerlings and adults than juveniles. The data obtained in the present study suggest that cathepsins and UbP genes in gilthead sea bream are co-ordinately regulated during ontogeny to control muscle growth, and indicate that feeding regimes can modulate their expression, providing a potential dietary method of influencing post-mortem fillet tenderisation, and hence, product quality

Proteolytic systems' expression during myogenesis and transcriptional regulation by amino acids in gilthead sea bream cultured muscle cells

Proteolytic systems exert an important role in vertebrate muscle controlling protein turnover, recycling of amino acids (AA) or its use for energy production, as well as other functions like myogenesis. In fish, proteolytic systems are crucial for the relatively high muscle somatic index they possess, and because protein is the most important dietary component. Thus in this study, the molecular profile of proteolytic markers (calpains, cathepsins and ubiquitin-proteasome system (UbP) members) were analyzed during gilthead sea bream (Sparus aurata) myogenesis in vitro and under different AA treatments. The gene expression of calpains (capn1, capn3 and capns1b) decreased progressively during myogenesis together with the proteasome member n3; whereas capn2, capns1a, capns1b and ubiquitin (ub) remained stable. Contrarily, the cathepsin D (ctsd) paralogs and E3 ubiquitin ligases mafbx and murf1, showed a significant peak in gene expression at day 8 of culture that slightly decreased afterwards. Moreover, the protein expression analyzed for selected molecules presented in general the same profile of the mRNA levels, which was confirmed by correlation analysis. These data suggest that calpains seem to be more important during proliferation, while cathepsins and the UbP system appear to be required for myogenic differentiation. Concerning the transcriptional regulation by AA, the recovery of their levels after a short starvation period did not show effects on cathepsins expression, whereas it down-regulated the expression of capn3, capns1b, mafbx, murf1 and up-regulated n3. With regards to AA deficiencies, the major changes occurred at day 2, when leucine limitation suppressed ctsb and ctsl expression. Besides at the same time, both leucine and lysine deficiencies increased the expression of mafbx and murf1 and decreased that of n3. Overall, the opposite nutritional regulation observed, especially for the UbP members, points out an efficient and complementary role of these factors that could be useful in gilthead sea bream diets optimization

Repositioning of the global epicentre of non-optimal cholesterol

High blood cholesterol is typically considered a feature of wealthy western countries(1,2). However, dietary and behavioural determinants of blood cholesterol are changing rapidly throughout the world(3) and countries are using lipid-lowering medications at varying rates. These changes can have distinct effects on the levels of high-density lipoprotein (HDL) cholesterol and non-HDL cholesterol, which have different effects on human health(4,5). However, the trends of HDL and non-HDL cholesterol levels over time have not been previously reported in a global analysis. Here we pooled 1,127 population-based studies that measured blood lipids in 102.6 million individuals aged 18 years and older to estimate trends from 1980 to 2018 in mean total, non-HDL and HDL cholesterol levels for 200 countries. Globally, there was little change in total or non-HDL cholesterol from 1980 to 2018. This was a net effect of increases in low- and middle-income countries, especially in east and southeast Asia, and decreases in high-income western countries, especially those in northwestern Europe, and in central and eastern Europe. As a result, countries with the highest level of non-HDL cholesterol-which is a marker of cardiovascular riskchanged from those in western Europe such as Belgium, Finland, Greenland, Iceland, Norway, Sweden, Switzerland and Malta in 1980 to those in Asia and the Pacific, such as Tokelau, Malaysia, The Philippines and Thailand. In 2017, high non-HDL cholesterol was responsible for an estimated 3.9 million (95% credible interval 3.7 million-4.2 million) worldwide deaths, half of which occurred in east, southeast and south Asia. The global repositioning of lipid-related risk, with non-optimal cholesterol shifting from a distinct feature of high-income countries in northwestern Europe, north America and Australasia to one that affects countries in east and southeast Asia and Oceania should motivate the use of population-based policies and personal interventions to improve nutrition and enhance access to treatment throughout the world.Peer reviewe

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

Worldwide trends in hypertension prevalence and progress in treatment and control from 1990 to 2019: a pooled analysis of 1201 population-representative studies with 104 million participants

Background Hypertension can be detected at the primary health-care level and low-cost treatments can effectively control hypertension. We aimed to measure the prevalence of hypertension and progress in its detection, treatment, and control from 1990 to 2019 for 200 countries and territories. Methods We used data from 1990 to 2019 on people aged 30–79 years from population-representative studies with measurement of blood pressure and data on blood pressure treatment. We defined hypertension as having systolic blood pressure 140 mm Hg or greater, diastolic blood pressure 90 mm Hg or greater, or taking medication for hypertension. We applied a Bayesian hierarchical model to estimate the prevalence of hypertension and the proportion of people with hypertension who had a previous diagnosis (detection), who were taking medication for hypertension (treatment), and whose hypertension was controlled to below 140/90 mm Hg (control). The model allowed for trends over time to be non-linear and to vary by age. Findings The number of people aged 30–79 years with hypertension doubled from 1990 to 2019, from 331 (95% credible interval 306–359) million women and 317 (292–344) million men in 1990 to 626 (584–668) million women and 652 (604–698) million men in 2019, despite stable global age-standardised prevalence. In 2019, age-standardised hypertension prevalence was lowest in Canada and Peru for both men and women; in Taiwan, South Korea, Japan, and some countries in western Europe including Switzerland, Spain, and the UK for women; and in several low-income and middle-income countries such as Eritrea, Bangladesh, Ethiopia, and Solomon Islands for men. Hypertension prevalence surpassed 50% for women in two countries and men in nine countries, in central and eastern Europe, central Asia, Oceania, and Latin America. Globally, 59% (55–62) of women and 49% (46–52) of men with hypertension reported a previous diagnosis of hypertension in 2019, and 47% (43–51) of women and 38% (35–41) of men were treated. Control rates among people with hypertension in 2019 were 23% (20–27) for women and 18% (16–21) for men. In 2019, treatment and control rates were highest in South Korea, Canada, and Iceland (treatment >70%; control >50%), followed by the USA, Costa Rica, Germany, Portugal, and Taiwan. Treatment rates were less than 25% for women and less than 20% for men in Nepal, Indonesia, and some countries in sub-Saharan Africa and Oceania. Control rates were below 10% for women and men in these countries and for men in some countries in north Africa, central and south Asia, and eastern Europe. Treatment and control rates have improved in most countries since 1990, but we found little change in most countries in sub-Saharan Africa and Oceania. Improvements were largest in high-income countries, central Europe, and some upper-middle-income and recently high-income countries including Costa Rica, Taiwan, Kazakhstan, South Africa, Brazil, Chile, Turkey, and Iran. Interpretation Improvements in the detection, treatment, and control of hypertension have varied substantially across countries, with some middle-income countries now outperforming most high-income nations. The dual approach of reducing hypertension prevalence through primary prevention and enhancing its treatment and control is achievable not only in high-income countries but also in low-income and middle-income settings

Paper de leptina i grelina sobre el teixit adipós i estudi de la proteolisi muscular en peixos = Role of leptin and ghrelin on adipose tissue and study of muscle proteolysis in fish

[cat] Els estudis que composen aquesta tesi tenen com a objectiu optimitzar el creixement muscular i reduir l'acumulació de greix en dues espècies d'aqüicultura, l’orada i la truita irisada. Primerament, es van identificar i caracteritzar en orada, alguns membres clau dels diferents sistemes proteolítics cel•lulars relacionats amb la degradació muscular com les calpaïnes (capn), catepsines (CTS) i via ubiquitina-proteasoma (UbP). La seva transcripció gènica muscular es va estudiar en orades: en tres etapes de la vida (aleví, juvenil i adult), sota dos estats nutricionals (dejuni i realimentació) i en resposta a dietes amb diferent nivell de proteïna i carbohidrat. En segon lloc, en truita irisada es va investigar in vivo l'efecte de l'adipositat sobre la leptina en plasma, i in vitro, el paper de certes hormones i nutrients en l’adipogènesi i en el metabolisme lipídic dels adipòcits. Finalment, es va establir per primera vegada, un cultiu primari de pre-adipòcits a partir de teixit adipós visceral en l'orada, i es van analitzar els efectes d'algunes hormones sobre la proliferació i la diferenciació cel•lular. Aquests estudis han demostrat que: a) l'expressió de les calpaïnes és modulada per l'estat nutricional i la composició de la dieta en l'orada, i que l'expressió de diversos membres del sistema de les calpaïnes es correlacionen amb la textura muscular, el que indica el seu potencial ús com a marcadors moleculars de la qualitat del filet d’orada, b) les SaCTSs i els membres del sistema SaUbP són reguladors del recanvi de les proteïnes musculars, l'expressió dels quals canvia durant la vida i en relació amb l'estat nutricional dels peixos, c) els nivells circulants de leptina poden transmetre informació sobre l'estat energètic del cos, i la regulació de la secreció de leptina dels adipòcits és modulada per la història nutricional dels peixos i per la influència d’hormones i nutrients, d) la grelina sembla ser una potenciadora del metabolisme lipídic en el teixit adipós de truita irisada, mentre que la leptina sembla regular-lo negativament. Aquests estudis han ajudat a entendre millor la proteòlisi muscular així com l’adipogènesi i el metabolisme lipídic d'aquestes espècies d'aqüicultura per millorar la seva qualitat.[eng] The studies included in this thesis aim to gain knowledge on skeletal muscle protein turnover and adipose tissue development and lipid metabolism regulation in two species of farmed fish to optimize its muscle growth and to reduce fat accumulation. To do this, we identified and characterized in skeletal muscle of gilthead sea bream (sa), some key members of the different cellular proteolytic systems: calpains (capn), cathepsins (CTS) and ubiquitin-proteasome pathway (UbP) related to muscle degradation. Then, muscle gene transcription was studied in gilthead sea bream at: three life stages (fingerlings, juveniles and adults), under two nutritional conditions (fasting and re-feeding) and in response to diets containing different levels of protein and carbohydrates. The most significant results were: a) the identified proteases showed the structural domains and the specific catalytic motifs to be functional as their orthologues in mammals, b) the reduction of the expression of saCTSs and saUbP members together with PCNA and MHC, indicated that muscle protein turnover is reduced with age; SaUb increased again in adults suggesting an increase in ubiquitination in this stage, c) fasting increased sacapns1b expression, whereas re-feeding decreased the expression of almost all proteases analyzed, indicating a negative regulation of proteolysis under anabolic conditions, d) the expression of sacapn1 and sacapns1a was modulated by diet composition, and correlated negatively with the texture of the fillet, pointing out to these genes as potential molecular markers of flesh quality in gilthead sea bream and, e) SaCTSDb showed higher expression in muscle and a distinct pattern of transcriptional regulation compared with SaCTSDa, supporting a more important role for SaCTSDb in muscle proteolysis. Furthermore, it was also investigated in vivo the effect of adiposity on plasma leptin, and in vitro, the role of certain hormones (leptin, ghrelin and insulin) and nutrients (leucine and EPA) on adipogenesis and lipid metabolism in rainbow trout. Finally, it was first established a primary culture of preadipocytes from visceral adipose tissue of gilthead sea bream and, the effects of some hormones (insulin, IGF -I and GH) on proliferation and differentiation were analyzed. The most relevant findings were: a) nutritional restriction decreased adipose tissue and liver weights but increased plasma leptin levels, which were negatively correlated, suggesting that this hormone can act as a nutritional signal regulating appetite, b) adipocytes and preadipocytes express and secrete leptin, contributing to the levels of plasma leptin; insulin and ghrelin increased leptin secretion in a dose-dependent manner in adipocytes of rainbow trout fed with a regular diet, c) rainbow trout adipocytes of fish nutritionally restricted secreted more leptin than those of fish fed to satiety. Besides, only adipocytes from feed restricted fish respond to leucine, a signal that could be interpreted as greater food availability, reducing the secretion of leptin, thus contributing to the stimulation of appetite, d) ghrelin activated lipid metabolism at different levels, increasing lipogenesis and oxidation as well as lipolysis. On the other hand, leptin was anti-lipogenic, as it increased lipolysis and inhibited the expression of a fatty acid transporter, e) leptin and ghrelin did not influence in vitro rainbow trout adipogenesis; however, ghrelin and its receptor were identified in mature adipocytes, indicating other possible endocrine or local effects of this hormone in this species, f) insulin, IGF-I and GH stimulated proliferation in preadipocytes of gilthead sea bream and, the presence of an adipogenic medium supplemented with lipids, as well as IGF -I stimulated differentiation. These studies have helped to better understand muscle proteolysis as well as adipogenesis and lipid metabolism in these aquaculture species to improve its qualit

Adipogenic gene expression in gilthead sea bream mesenchymal stem cells from different origin

During the last decades, adipogenesis has become an emerging field of study in aquaculture due to the relevance of the adipose tissue in many physiological processes and its connection with the endocrine system. In this sense, recent studies have translated into the establishment of preadipocyte culture models from several fish species, lacking sometimes information on the mRNA levels of adipogenic genes. Thus, the aim of this study was to determine the gene expression profile of gilthead sea bream (Sparus aurata) primary cultured mesenchymal stem cells (MSCs) from different origin (adipose tissue and vertebra bone) during adipogenesis. Both cell types differentiated into adipocyte-like cells accumulating lipids inside their cytoplasm. Adipocyte differentiation of MSCs from adipose tissue resulted in down-regulation of several adipocyte-related genes (such as lpl, hsl, pparα, pparγ and gapdh2) at day 4, gapdh1 at day 8, and fas and pparβ at day 12. In contrast, differences in lxrα mRNA expression were not observed, while g6pdh levels increased during adipocyte maturation. Gapdh and Pparγ protein levels were also detected in preadipocyte cultures; however, only the former increased its expression during adipogenesis. Moreover, differentiation of bone-derived cells into adipocytes also resulted in the down-regulation of several adipocyte gene markers such as fas and g6pdh at day 10 and hsl, pparβ and lxrα at day 15. On the other hand, the osteogenic genes fib1a, mgp and op remained stable, but an increase in runx2 expression at day 20 was observed. In summary, the present study demonstrates that gilthead sea bream MSCs from both adipose tissue and bone differentiate into adipocyte-like cells, although revealed some kind of species- and cell lineage-specific regulation with regards to gene expression. Present data also provide novel insights into some of the potential key genes controlling adipogenesis in gilthead sea bream that can help to better understand the regulation of lipid storage in fish

Characterisation and expression analysis of cathepsins and ubiquitin-proteasome genes in gilthead sea bream (Sparus aurata) skeletal muscle

The proteolytic enzymes involved in normal protein turnover in fish muscle are also responsible for post-mortem softening of the flesh and are therefore potential determinants of product quality. The main enzyme systems involved are calpains, cathepsins, and the ubiquitin-proteasome (UbP). In this study on Sparus aurata (Sa), the coding sequences of cathepsins (SaCTSB and SaCTSDb) and UbP family members (SaN3 and SaUb) were cloned from fast skeletal muscle, and their expression patterns were examined during ontogeny and in a fasting/re-feeding experiment. The amino acid sequences identified shared 66-100% overall identity with their orthologues in other vertebrates, with well conserved characteristic functional domains and catalytic residues. SaCTSDb showed phylogenetic, sequence and tissue distribution differences with respect to its paralogue SaCTSDa, previously identified in the ovary. Expression of gilthead sea bream cathepsins (B, L, Da, Db) and UbP members (N3, Ub, MuRF1 and MAFbx) in fast skeletal muscle was determined at three different life-history stages and in response to fasting and re-feeding in juveniles. Most of the proteolytic genes analysed were significantly up-regulated during fasting, and down-regulated with re-feeding and, between the fingerling (15 g) and juvenile/adult stages (~50/500 g), consistent with a decrease in muscle proteolysis in both later contexts. In contrast, SaCTSDa and SaMuRF1 expression was relatively stable with ontogeny and SaUb had higher expression in fingerlings and adults than juveniles. The data obtained in the present study suggest that cathepsins and UbP genes in gilthead sea bream are co-ordinately regulated during ontogeny to control muscle growth, and indicate that feeding regimes can modulate their expression, providing a potential dietary method of influencing post-mortem fillet tenderisation, and hence, product quality

Adipogenic gene expression in gilthead sea bream mesenchymal stem cells from different origin

During the last decades, adipogenesis has become an emerging field of study in aquaculture due to the relevance of the adipose tissue in many physiological processes and its connection with the endocrine system. In this sense, recent studies have translated into the establishment of preadipocyte culture models from several fish species, lacking sometimes information on the mRNA levels of adipogenic genes. Thus, the aim of this study was to determine the gene expression profile of gilthead sea bream (Sparus aurata) primary cultured mesenchymal stem cells (MSCs) from different origin (adipose tissue and vertebra bone) during adipogenesis. Both cell types differentiated into adipocyte-like cells accumulating lipids inside their cytoplasm. Adipocyte differentiation of MSCs from adipose tissue resulted in down-regulation of several adipocyte-related genes (such as lpl, hsl, pparα, pparγ and gapdh2) at day 4, gapdh1 at day 8, and fas and pparβ at day 12. In contrast, differences in lxrα mRNA expression were not observed, while g6pdh levels increased during adipocyte maturation. Gapdh and Pparγ protein levels were also detected in preadipocyte cultures; however, only the former increased its expression during adipogenesis. Moreover, differentiation of bone-derived cells into adipocytes also resulted in the down-regulation of several adipocyte gene markers such as fas and g6pdh at day 10 and hsl, pparβ and lxrα at day 15. On the other hand, the osteogenic genes fib1a, mgp and op remained stable, but an increase in runx2 expression at day 20 was observed. In summary, the present study demonstrates that gilthead sea bream MSCs from both adipose tissue and bone differentiate into adipocyte-like cells, although revealed some kind of species- and cell lineage-specific regulation with regards to gene expression. Present data also provide novel insights into some of the potential key genes controlling adipogenesis in gilthead sea bream that can help to better understand the regulation of lipid storage in fish

Proteolytic systems' expression during myogenesis and transcriptional regulation by amino acids in gilthead sea bream cultured muscle cells

Proteolytic systems exert an important role in vertebrate muscle controlling protein turnover, recycling of amino acids (AA) or its use for energy production, as well as other functions like myogenesis. In fish, proteolytic systems are crucial for the relatively high muscle somatic index they possess, and because protein is the most important dietary component. Thus in this study, the molecular profile of proteolytic markers (calpains, cathepsins and ubiquitin-proteasome system (UbP) members) were analyzed during gilthead sea bream (Sparus aurata) myogenesis in vitro and under different AA treatments. The gene expression of calpains (capn1, capn3 and capns1b) decreased progressively during myogenesis together with the proteasome member n3; whereas capn2, capns1a, capns1b and ubiquitin (ub) remained stable. Contrarily, the cathepsin D (ctsd) paralogs and E3 ubiquitin ligases mafbx and murf1, showed a significant peak in gene expression at day 8 of culture that slightly decreased afterwards. Moreover, the protein expression analyzed for selected molecules presented in general the same profile of the mRNA levels, which was confirmed by correlation analysis. These data suggest that calpains seem to be more important during proliferation, while cathepsins and the UbP system appear to be required for myogenic differentiation. Concerning the transcriptional regulation by AA, the recovery of their levels after a short starvation period did not show effects on cathepsins expression, whereas it down-regulated the expression of capn3, capns1b, mafbx, murf1 and up-regulated n3. With regards to AA deficiencies, the major changes occurred at day 2, when leucine limitation suppressed ctsb and ctsl expression. Besides at the same time, both leucine and lysine deficiencies increased the expression of mafbx and murf1 and decreased that of n3. Overall, the opposite nutritional regulation observed, especially for the UbP members, points out an efficient and complementary role of these factors that could be useful in gilthead sea bream diets optimization