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Galectin-3 is an endogenous lectin which binds mainly to β-galactosides on the cell surface and extracellular matrix (ECM) glycoproteins. In the thymus, this lectin is constitutively expressed, being involved in thymocyte adhesion, migration, and death. Galectin-3 has been related to type 1 diabetes, an autoimmune disease characterized by pancreatic β-cell destruction mediated by autoreactive T lymphocytes. Non-obese diabetic (NOD) mice represent a suitable model to study type 1 diabetes, as they develop the disease like humans. We previously described important thymic alterations in these animals such as the development of giant perivascular spaces (PVS), characterized by the retention of T and B cells, intermingled with an ECM network, and associated with a defect in the expression of the fibronectin receptor VLA-5 and reduced sphingosine-1-phosphate receptor expression on developing thymocytes. In order to investigate galectin-3 expression in thymic microenvironmental cells and verify its interaction with cells and ECM molecules in PVS, we performed immunofluorescence following colocalization analysis in the thymic parenchyma of pre-diabetic NOD mice by confocal microscopy. In addition, thymocyte migration assays were performed to evaluate the effect of galectin-3 on NOD thymocyte migration. Herein, we showed a significant enhancement of colocalization with cortical and medullary thymic epithelial cells in NOD mice, as compared to controls. In the giant PVS of these animals, we observed a heterogeneous distribution of galectin-3, predominantly found in clusters of B lymphocytes and dendritic cells. Functionally, NOD thymocyte migratory response towards galectin-3 was impaired and a similar decrease was seen in transendothelial thymocyte migration. Taken together, our data provide the histological and functional background for a potential defective thymocyte migration involving galectin-3, thus placing this molecule as a further player in the intrathymic disturbances observed in pre-diabetic NOD mice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ramos, Ventura, Lemos, Chammas, Savino, Carvalho-Pinto, Mendes-da-Cruz and Villa-Verde.)

Growing evidence demonstrates a continuous interaction between the immune system, the nerve and the muscle in neuromuscular disorders of different pathogenetic origins, such as Duchenne Muscular Dystrophy (DMD) and Amyotrophic Lateral Sclerosis (ALS), the focus of this review. Herein we highlight the complexity of the cellular and molecular interactions involving the immune system in neuromuscular disorders, as exemplified by DMD and ALS. We describe the distinct types of cell-mediated interactions, such as cytokine/chemokine production as well as cell-matrix and cell-cell interactions between T lymphocytes and other immune cells, which target cells of the muscular or nervous tissues. Most of these interactions occur independently of exogenous pathogens, through ligand-receptor binding and subsequent signal transduction cascades, at distinct levels of specificity. Although this issue reveals the complexity of the system, it can also be envisioned as a window of opportunity to design therapeutic strategies (including synthetic moieties, cell and gene therapy, as well as immunotherapy) by acting upon one or more targets. In this respect, we discuss ongoing clinical trials using VLA-4 inhibition in DMD, and in ALS, with a focus on regulatory T cells, both revealing promising results., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lemos, Tenório, Mouly, Butler-Browne, Mendes-da-Cruz, Savino and Smeriglio.)

The magnitude and quality of the germinal center (GC) response decline with age, resulting in poor vaccine-induced immunity in older individuals. A functional GC requires the co-ordination of multiple cell types across time and space, in particular across its two functionally distinct compartments: the light and dark zones. In aged mice, there is CXCR4-mediated mislocalization of T follicular helper (T FH ) cells to the dark zone and a compressed network of follicular dendritic cells (FDCs) in the light zone. Here we show that T FH cell localization is critical for the quality of the antibody response and for the expansion of the FDC network upon immunization. The smaller GC and compressed FDC network in aged mice were corrected by provision of T FH cells that colocalize with FDCs using CXCR5. This demonstrates that the age-dependent defects in the GC response are reversible and shows that T FH cells support stromal cell responses to vaccines., (© 2023. The Author(s).)

WHIM Syndrome is a rare immunodeficiency caused by gain-of-function CXCR4 mutations. Here we report a decrease in bone mineral density in 25% of WHIM patients and bone defects leading to osteoporosis in a WHIM mouse model. Imbalanced bone tissue is observed in mutant mice combining reduced osteoprogenitor cells and increased osteoclast numbers. Mechanistically, impaired CXCR4 desensitization disrupts cell cycle progression and osteogenic commitment of skeletal stromal/stem cells, while increasing their pro-osteoclastogenic capacities. Impaired osteogenic differentiation is evidenced in primary bone marrow stromal cells from WHIM patients. In mice, chronic treatment with the CXCR4 antagonist AMD3100 normalizes in vitro osteogenic fate of mutant skeletal stromal/stem cells and reverses in vivo the loss of skeletal cells, demonstrating that proper CXCR4 desensitization is required for the osteogenic specification of skeletal stromal/stem cells. Our study provides mechanistic insights into how CXCR4 signaling regulates the osteogenic fate of skeletal cells and the balance between bone formation and resorption., (© 2023. The Author(s).)

The bone marrow is a complex ecosystem in which hematopoietic and non-hematopoietic cells reside. In this review, we discuss the bone marrow niches in mice that facilitate the survival, maintenance, and differentiation of cells of hematopoietic origin based on the recent literature. Our review places a special focus on the hematopoietic multipotent progenitors and on plasma cells, corresponding to the last stage of the B-cell lineage, that play a key role in the humoral memory response. We highlight the similarities between the microenvironments necessary for the establishment and the maintenance of these two immune cell subsets, and how the chemokine CXCL12/CXCR4 signaling axis contributes to these processes. Finally, we bring elements to address the following question: are multipotent progenitors and plasma cells neighbors or roommates within the bone marrow?, Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bonaud, Lemos, Espéli and Balabanian.)

The effect of Spirulina (Arthrospira platensis), individually or in combination with two commercial carbohydrases, in piglet diets was assessed on growth performance, nutrient digestibility and meat quality traits. Forty post-weaned male piglets from Large White × Landrace sows crossed with Pietrain boars with an initial live weight of 12.0 ± 0.89 kg were used. Piglets were assigned to one of four dietary treatments (n = 10): cereal and soya bean meal base diet (control), base diet with 10% Spirulina (SP), SP diet supplemented with 0.005% Rovabio ® Excel AP (SP + R) and SP diet supplemented with 0.01% lysozyme (SP + L). Animals were slaughtered after a 4-week experimental period. Growth performance was negatively affected by the incorporation of Spirulina in the diets, with an average decrease of 9.1% on final weight, in comparison with control animals. Total tract apparent digestibility (TTAD) of crude protein was higher (p < .05) in the control group than in other groups. In addition, lysozyme increased TTAD of crude fat and acid detergent fibre, relative to the SP and control groups, respectively. In addition, the incorporation of Spirulina, individually and supplemented with enzymes, did not impair meat quality traits. Surprisingly, no protective effect against lipid oxidation was observed with the inclusion of Spirulina in pork after 7 days of storage. This study indicates that growth performance of post-weaning piglets was impaired by the incorporation of 10% Spirulina in the diets, which is mediated by an increase in digesta viscosity and a lower protein digestibility, as a consequence of the resistance of microalga proteins to the action of endogenous peptidases. In addition, it also indicates that lysozyme, in contrast to Rovabio ® Excel AP, is efficient in the degradation of Spirulina cell wall in piglet's intestine. However, the digestion of proteins liberated by Spirulina cell wall disruption is still a challenge., (© 2020 Wiley-VCH GmbH.)

Background: Zika virus (ZIKV) infection gained public health concern after the 2015 outbreak in Brazil, when microcephaly rates increased in babies born from infected mothers. It was demonstrated that ZIKV causes a congenital Zika virus syndrome, including various alterations in the development of the central nervous system. Although the infection of cells from the nervous system has been well documented, less is known in respect of ZIKV ability to infect immune cells. Herein, we investigated if peripheral blood mononuclear cells (PBMCs), freshly-isolated from healthy donors, could be infected by ZIKV., Methods: PBMCs from healthy donors were isolated and cultured in medium with ZIKV strain Rio-U1 (MOI = 0.1). Infection was analyzed by RT-qPCR and flow cytometry., Results: We detected the ZIKV RNA in PBMCs from all donors by RT-qPCR analysis. The detection of viral antigens by flow cytometry revealed that PBMC from more than 50% the donors were infected by ZIKV, with CD3 + CD4 + T cells, CD3 - CD19 + B cells and CD3 + CD8 + T cells being, respectively, the most frequently infected subpopulations, followed by CD14 + monocytes. Additionally, we observed high variability in PBMC infection rates among different donors, either by numbers or type infected cells., Conclusions: These findings raise the hypothesis that PBMCs can act as a reservoir of the virus, which may facilitate viral dissemination to different organs, including immune-privileged sites.

Type 1 diabetes (T1D) is an autoimmune disease caused by the destruction of insulin-producing cells in the pancreas, by direct interactions with autoreactive pancreas infiltrating T lymphocytes (PILs). One of the most important animal models for this disease is the non-obese diabetic (NOD) mouse. Alterations in the NOD mouse thymus during the pathogenesis of the disease have been reported. From the initial migratory disturbances to the accumulation of mature thymocytes, including regulatory Foxp3 + T cells, important mechanisms seem to regulate the repertoire of T cells that leave the thymus to settle in peripheral lymphoid organs. A significant modulation of the expression of extracellular matrix and soluble chemoattractant molecules, in addition to integrins and chemokine receptors, may contribute to the progressive accumulation of mature thymocytes and consequent formation of giant perivascular spaces (PVS) that are observed in the NOD mouse thymus. Comparative large-scale transcriptional expression and network analyses involving mRNAs and miRNAs of thymocytes, peripheral T CD3 + cells and PILs provided evidence that in PILs chemokine receptors and mRNAs are post-transcriptionally regulated by miR-202-3p resulting in decreased activity of these molecules during the onset of T1D in NOD mice. In this review, we discuss the abnormal T-cell development in NOD mice in the context of intrathymic expression of different migration-related molecules, peptides belonging to the family of insulin and insulin-like growth factors as well as the participation of miRNAs as post-transcriptional regulators and their possible influence on the onset of aggressive autoimmunity during the pathogenesis of T1D.

NOD (non-obese diabetic) mice spontaneously develop type 1 diabetes following T cell-dependent destruction of pancreatic &beta; cells. Several alterations are observed in the NOD thymus, including the presence of giant perivascular spaces (PVS) filled with single-positive (SP) CD4⁺ and CD8⁺ T cells that accumulate in the organ. These cells have a decreased expression of membrane CD49e (the &alpha;5 integrin chain of the fibronectin receptor VLA-5 (very late antigen-5). Herein, we observed lower sphingosine-1-phosphate receptor 1 (S1P1) expression in NOD mouse thymocytes when compared with controls, mainly in the mature SP CD4⁺CD62L hi and CD8⁺CD62L hi subpopulations bearing the CD49e &minus; phenotype. In contrast, differences in S1P1 expression were not observed in mature CD49e⁺ thymocytes. Functionally, NOD CD49e &minus; thymocytes had reduced S1P-driven migratory response, whereas CD49e⁺ cells were more responsive to S1P. We further noticed a decreased expression of the sphingosine-1-phosphate lyase (SGPL1) in NOD SP thymocytes, which can lead to a higher sphingosine-1-phosphate (S1P) expression around PVS and S1P1 internalization. In summary, our results indicate that the modulation of S1P1 expression and S1P/S1P1 interactions in NOD mouse thymocytes are part of the T-cell migratory disorder observed during the pathogenesis of type 1 diabetes.

The traditional beef production in the South of Portugal is based on a discontinuous growth (DG) system that requires lower external inputs and could enhance meat quality and financial returns to cattle producers. This system allows farmers to take advantage of the bull's compensatory growth when the pasture is abundant and finishes the cattle on concentrates for 2 to 3 months before slaughter. The fast gain rate before slaughter could be a valuable strategy to improve tenderness and to reduce its inconsistency in beef production. Therefore, the aim of this study was to evaluate the effects of production system (continuous growth (CG) v. DG) on longissimus thoracis muscle properties from Alentejana bulls. In total, 40 Alentejana male calves were allocated to two distinct feeding regimes: in the CG system, animals were fed concentrate plus hay and slaughtered at 18 months of age, whereas in the DG system, animals were fed on hay until 15 months of age and then fed the same diet provided to the CG group until 24 months of age. The DG system had a positive impact on meat tenderness (P<0.001) and global acceptability (P<0.001). DG bulls had greater fibre cross-sectional area (CSA) of glycolytic fibres (P<0.05) and relative area of the muscle (RA) occupied by type IIX fibres (P<0.01) and greater levels of α-actinin (P<0.05) and myosin light chain 2 (P<0.01) proteins, and pH24h (P<0.01) than CG bulls. The latter had greater CSA of type I (P<0.05) and type IIA (P<0.01) and greater RA of type IIA (P<0.05) and oxidative (P<0.05) than CG bulls. The compensatory growth production system had a positive impact on meat tenderness and global acceptability, overcoming the negative effects of slaughter of the bulls at a later age. The DG beef system could be a worthwhile strategy of beef production in Mediterranean areas due to the low-quality pasture in summer.

Purpose: The autonomic maneuvers are simple methods to evaluate autonomic balance, but the association between autonomic maneuvers and heart rate variability (HRV) in hemodialysis patients remains unknown. This study aimed to evaluate the correlation between HRV and respiratory sinus arrhythmia (RSA) and Valsalva maneuver (VM) indexes in hemodialysis patients and to compare two methods for RSA indexes acquisitions., Methods: Forty-eight volunteers on hemodialysis (66.7 % men) were evaluated by VM, RSA, and 24 h Holter monitoring. At the VM, the Valsalva index (VI) was the variable considered. In the RSA, the ratio and difference between the RR intervals of inspiratory and expiratory phase (E:I and E-I, respectively) were considered by traditional form (average of respiratory cycles) and independent respiratory cycles (E:Iindep and E-Iindep). The HRV indexes evaluated were standard deviation of all normal RR intervals (SDNN), standard deviation of sequential 5-min RR interval means (SDANN), root mean square of the successive differences (rMSSD) and percentage of adjacent RR intervals with difference of duration greater than 50 ms (pNN50)., Results: The SDNN, SDANN showed significant correlation with all classic indexes of RSA (E:I: r = 0.62, 0.55, respectively, E-I: r = 0.64, 0.57, respectively), E:Iindep (r = 0.59, 0.54, respectively), E-Iindep (r = 0.47, 0.43, respectively) and VI (r = 0.42, 0.34, respectively). Significant correlation of rMSSD with E:I (r = 0.37), E-I (r = 0.41) and E:Iindep (r = 0.34) was also observed. There was no association of any variable with pNN50. Have been show high values for all variables of independent cycles method (p < 0.05)., Conclusion: The autonomic maneuvers, especially RSA, are useful methods to evaluate cardiac autonomic function in hemodialysis patients. The acquisition of the RSA index by independent cycles should not be used in this population.

Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid involved in several physiological processes including cell migration and differentiation. S1P signaling is mediated through five G protein-coupled receptors (S1P1-S1P5). S1P1 is crucial to the exit of T-lymphocytes from the thymus and peripheral lymphoid organs through a gradient of S1P. We have previously observed that T-ALL and T-LBL blasts express S1P1. Herein we analyzed the role of S1P receptors in the migratory pattern of human T-cell neoplastic blasts. S1P-triggered cell migration was directly related to S1P1 expression. T-ALL blasts expressing low levels of S1P1 mRNA (HPB-ALL) did not migrate toward S1P, whereas those expressing higher levels of S1P1 (MOLT-4, JURKAT and CEM) did migrate. The S1P ligand induced T-ALL cells chemotaxis in concentrations up to 500 nM and induced fugetaxis in higher concentrations (1000-10000 nM) through interactions with S1P1. When S1P1 was specifically blocked by the W146 compound, S1P-induced migration at lower concentrations was reduced, whereas higher concentrations induced cell migration. Furthermore, we observed that S1P/S1P1 interactions induced ERK and AKT phosphorylation, and modulation of Rac1 activity. Responding T-ALL blasts also expressed S1P3 mRNA but blockage of this receptor did not modify migratory responses. Our results indicate that S1P is involved in the migration of T-ALL/LBL blasts, which is dependent on S1P1 expression. Moreover, S1P concentrations in the given microenvironment might induce dose-dependent chemotaxis or fugetaxis of T-ALL blasts.

Forty entire male pigs from a commercial crossbreed (Duroc × Large White × Landrace) were used to investigate the individual or combined effects of betaine and Arg supplementation in Lys-deficient diets on growth performance, carcass traits, and pork quality. Pigs with 59.9 ± 1.65 kg BW were randomly assigned to 1 of 5 dietary treatments ( = 8). The 5 dietary treatments were normal Lys and CP diet (0.51% Lys and 16% CP; control), reduced Lys and CP diet (0.35% Lys and 13% CP), reduced Lys and CP diet with betaine supplementation (0.33%), reduced Lys and CP diet with Arg supplementation (1.5%), and reduced Lys and CP diet with betaine and Arg supplementation (0.33% betaine and 1.5% Arg). Pigs were slaughtered at 92.7 ± 2.54 kg BW. The Lys-deficient diets (-35% Lys) increased intramuscular fat (IMF) content by 25% ( = 0.041) and meat juiciness by 12% ( = 0.041) but had a negative effect on growth performance ( < 0.05) of pigs. In addition, Lys-deficient diets increased L* ( = 0.005) and b* ( = 0.010) muscle color parameters and perirenal fat deposition ( < 0.001) and decreased both HCW ( = 0.015) and loin weight ( = 0.023). Betaine and Arg supplementation of Lys-deficient diets had no effect on IMF content but increased ( < 0.05) overall pork acceptability. Arginine supplementation also increased ( = 0.003) meat tenderness. Differences in fatty acid composition of pork were not detected among dietary treatment groups. However, oleic acid was positively correlated ( < 0.05) with IMF content, juiciness, flavor, and overall acceptability of meat. Data confirm that dietary CP reduction enhances pork eating quality but negatively affects pigs' growth performance. Moreover, it is suggested that betaine and Arg supplementation of Lys-deficient diets does not further increase IMF content but improves some pork sensory traits, including overall acceptability.

The aim of this study was to evaluate the carcass and meat characteristics of eight muscles from bulls with distinct growth paths. A total of 40 Alentejana male calves were allocated to two distinct feeding regimes. In the continuous growth (CG) system, the animals were fed concentrates plus hay and were slaughtered at 18 months of age. On the other hand, in the discontinuous growth (DG) system, the animals were fed hay until 15 months of age; the cattle were then fed the same diet provided to the CG group from 15 to 24 months of age. The DG reduced hot carcass weight, fatness and dressing %, but the proportions of fat, bone and muscle tissues in the leg were not affected. In contrast, there was a positive impact of compensatory growth on supraspinatus, triceps brachii, semitendinosus, biceps femoris muscle tenderness, overcoming the negative effects of age at slaughter. The reasons for such improvement in meat tenderness were not related to intra-muscular fat content or myofibrillar protein degradation values. An association between tenderness and muscle collagen properties was not established. The results indicate that the compensatory growth has a muscle-dependent effect.

The effect of commonly household cooking methods (boiling, microwaving and grilling) on amino acid and mineral (Fe, Mg, K and Zn) contents was investigated in the longissimus lumborum muscle of Barrosã-PDO veal. Fifteen Barrosã purebred calves at 7-8 months of age and an average weight of 177±37 kg were slaughtered. Cooking had a strong effect (P<0.05) on yield, being higher (67.5%) in boiling compared to microwave and grilling (64.0% and 64.5%, respectively). Grilling increased most of the percentage retention of individual amino acids (>100%), in particular for leucine. No significant differences (P>0.05) were observed for iron and zinc retentions among the cooking methods, while the retention of magnesium and potassium was strongly affected, mainly after boiling. Our findings indicate that the different cooking methods clearly affect the chemical composition and nutritional value of meat, which may have a strong impact on the intake of essential nutrients., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Fifty-four entire male pigs (Duroc × Pietrain × Large White × Landrace) from a commercial crossbred operation were used to investigate the effect of dietary Arg supplementation, protein reduction (PR), and Leu supplementation on performance, carcass traits, and meat quality. Pigs weighing 58.9 ± 1.6 kg BW were randomly assigned to 1 of 6 treatments (n = 9). The 6 dietary treatments were normal CP diet (16% CP, NPD), reduced CP diet (13% CP, RPD), reduced CP diet with Leu addition to 2.0% (RPDL), normal CP diet supplemented with 1% Arg (16% CP, Arg-NPD), reduced CP diet supplemented with 1% Arg (13% CP, Arg-RPD), and reduced CP diet with Leu addition to 2.0% and supplemented with 1% Arg (13% CP, Arg-RPDL). Pigs were slaughtered at 91.7 ± 1.6 kg BW. Dietary Arg supplementation had no effect on intramuscular fat (IMF) content but produced meat off-flavor and increased meat tenderness and overall acceptability. The PR increased (P < 0.001) IMF content (45% to 48%) but negatively affected the growth performance of pigs. In addition, PR increased (P < 0.05) back fat thickness and decreased loin weight. Leucine addition did not affect IMF content, back fat thickness, or loin weight. There was an increase of juiciness with PR and Leu addition, which accompanied the increase of IMF content with the low-CP diet. The PR increased meat deposition of 18:1c9, SFA, MUFA, and PUFA, which were not correlated with any pork sensory trait. The main combined effect of Arg was an increased tenderness and overall acceptability of pork. In conclusion, it was confirmed that dietary CP reduction enhances pork eating quality but negatively affects growth performance and carcass characteristics of pigs.

Physicochemical characteristics were determined in the longissimus lumborum muscle, after 8 days of ageing of steers (n=12) and bulls (n=12) from Mertolenga breed slaughtered directly from pasture (day 0) or after a finishing period of 50, 100 and 150 days in a feed-lot facility. Bulls and steers presented similar live weight (averaging 388 kg), carcass weight (CW; averaging 213 kg), dressing percentage (averaging 60%), carcass fatness (11.9% CW) and carcass fat thickness (averaging 3.03 mm). Live weight, CW, carcass fatness and fat thickness increased along time-on-feed. Gender only had a negligible effect on meat characteristics, with b and h being the only parameters of colour affected by gender, also presenting a significant interaction gender × time-on-feed. Nevertheless, both the genders presented a high-quality grade concerning tenderness (Warner-Bratzler shear force (WBSF)). L increased until 50 days on feed and decreased afterwards, whereas a and C values increased along time-on-feed. Pigment content was also affected by time-on-feed and showed a gender × time-on-feed interaction. Beef colour became darker and redder along time-on-feed, but still in a colour range highly acceptable by Portuguese consumers. Despite the increase in intramuscular fat and myofibrillar fragmentation index, as well as the decrease in collagen content of steers and bulls along time-on-feed, it did not affect the tenderness/hardness, indicating a small effect of time-on-feed in meat characteristics. Despite only small differences in carcass characteristics and meat-quality parameters that have been noticed along time-on-feed, those differences were only significant after 100 days on feed. Principal component analysis (PCA) was performed. The first PC axis (39.6% of the total variance) included colour variables a, b and C, and carcass fatness, fat thickness, CW and live weight, whereas the second one (12.7% of the total variance) included h, cooking losses and dressing-out. The principal component (PC) analysis confirmed the lack of differences between bulls and steers and indicates a differentiation of the first two periods of feeding (0 and 50 days on feed) from the two latter (100 and 150 days on feed) periods of feeding.

1. Chicken breast meat is a lean meat due to its low content of intramuscular fat (IMF) resulting in an overall lower acceptability by consumers due to a decrease in juiciness, flavour and increased chewiness. Recently, studies performed in pigs suggested the possibility of increasing IMF by decreasing dietary crude protein (CP) content, an effect possibly mediated through an increased lipogenesis. 2. Dietary supplementation with lipids rich in omega 3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) may modulate an increase in the content of these fatty acids in meat from monogastric animals and, thus, promote the daily intake of n-3 LC-PUFA by humans. 3. LC-PUFA are very susceptible to oxidation, resulting in off-flavours that affect meat quality and consumers' acceptability. 4. This trial was conducted to assess the effect of reducing dietary CP, from 21% to 17%, on chicken's meat IMF content and, simultaneously, to evaluate if a complementary supplementation with a proprietary n-3 LC-PUFA source (DHA Gold™) could improve meat quality. These effects were assessed by measuring productive performance and meat quality, oxidative stability, sensory traits and fatty acid profile. 5. A reduction in CP content of broiler diets, from 21% to 17%, balanced for lysine, improved performance while it was not sufficient to increase IMF content in chicken meat. In contrast, DHA Gold™ supplementation had a positive impact both in broiler productive parameters and in meat fatty acid profile. 6. In addition, incorporation of 7.4% of DHA Gold™ in the diet promoted carcass yield but negatively affected chicken meat acceptability by consumers, due to a decrease of meat oxidative stability. 7. Overall the data suggest that neither a dietary supplementation with DHA Gold™ nor a reduction in CP have a direct positive effect in the levels of IMF present in broiler meat.

The survival of plants in epiphytic environments depends on vegetative adaptations capable to defraud different stresses. Based on the structural diversity of the Orchidaceae, the current study has the objective of relating the anatomical structure of Dichaea cogniauxiana and Epidendrum secundum with the distinct environments where they live. It was expected that, despite structural similarities as strategies for resource acquisition, some peculiar variations related to the distinct light microenvironments (inside or in the edge of the nebular forest, near to "campo rupestre" area) might be found. Leaves and roots of both species were collected in a nebular forest located at a "campo rupestre" area at Serra da Piedade, Brazil), in January and February 2005. D. cogniauxiana is adhered to trunks, in sites with high atmospheric humidity and shaded, while E. secundum is located at the edge of the nebular forest, in more luminous sites. The leaves of E. secundum had thicker cuticle and higher number of stomata per area than those of D. cogniauxiana, characteristics coherent with their distinct pattern of exhibition to sun light. The suprastomatic chambers formed by the thicker cuticle may function as a barrier of resistance to water evaporation. The succulence of the leaves of E. secundum propitiates organic acids storage at night, and the storage of starch may be involved in PEP-carboxylase metabolism, both propitiating CAM mechanism. Roots with larger number of cell layers of the velamen, and specialized thick walled cortical cells (both in E. secundum) help water absorption and indicate better adaptation to an environment with intense solar radiation and a probable higher water deficit. The remarkable cell wall thickening of E. secundum exodermis can confer more efficient protection against the excess of transpiration at the border of the nebular forest. On the other hand, besides D. cogniauxiana be epiphyte, it is in a low position - in a shaded environment and with high relative humidity. Its thin thickened velamen permits the entrance of the low available light, and photosynthesis, producing oxygen and helping to avoid hypoxia condition. As features registered for D. cogniauxiana and E. secundum roots, we can depict the velamen, distinct exodermis and endodermis, and specialized thick walled cortical cells as characteristic of epiphytic plants.

Sixty entire male pigs from 2 distinct genotypes (30 Alentejano purebred, an autochthonous fatty genotype, and 30 commercial crossbred pigs, a lean genotype) were used to investigate the effects of dietary CP reduction and low-Lys levels on growth performance, carcass traits, and meat quality. Pigs with 59.9 ± 2.0 kg BW were randomly assigned within each genotype to 1 of 3 diets [normal CP diet (control), reduced CP diet adjusted for Lys (RPDL), and reduced CP diet not adjusted for Lys (RPD)] as a 2 × 3 factorial arrangement of treatments with 10 individually fed pigs per treatment. Pigs were slaughtered at 93.4 ± 2.4 kg BW. The results showed that intramuscular fat (IMF) content of longissimus lumborum muscle was greater in Alentejano than crossbred pigs (5.0 vs. 2.4%). The RPDL had no effect on IMF content, ADG, backfat thickness, and loin weight in both genotypes. The RPD promoted the increase (P < 0.05) in IMF content in crossbred (∼50%) but not Alentejano pigs, which indicates that Lys restriction can mediate the effect of RPD. Within crossbred pigs, meat obtained from pigs fed RPD had an increased IMF content (+1.3%) and a tendency for greater sensory scores (tenderness, juiciness, flavor, and acceptability) than those fed the control. The IMF content was positively correlated to flavor in Alentejano genotype (P < 0.05) but not in crossbred pigs. Alentejano and crossbred pigs had a greater tendency to deposit 18:1c9 and SFA, respectively. Despite the contribution of fatty acid composition to flavor, its influence on pork acceptability was more noticeable in crossbred than Alentejano pigs. In conclusion, the increased IMF promoted by dietary CP reduction in lean but not in fatty pig genotypes during the growing-finishing period is likely due to Lys limitation, which seems to enhance eating quality of pork.

Physicochemical and sensory characteristics were measured in veal and beef from the Portuguese Mertolenga breed having 3 quality labels as follows: Mertolenga-PDO beef and veal which apply to purebred animals and "Vitela Tradicional do Montado"-PGI veal which applies to crossbred animals. Measurements were made in longissimus lumborum muscle aged for 6days. The temperature 3h post-mortem (T3), cooking losses and Warner-Bratzler shear force (WBSF) reflected carcass weight (CW) differences between groups. The pigment content was influenced by age, with beef having higher values than veal. WBSF correlated negatively with intramuscular fat in Mertolenga-PDO beef, but not on veal. WBSF correlated positively with cooking losses and negatively with myofibrillar fragmentation index, tenderness, juiciness and overall acceptability. Cooking losses and juiciness were the main contributors for the tenderness differences. Vitela Tradicional do Montado-PGI and Mertolenga-PDO veal had lighter colour and were considered tender. The three meat types were well discriminated based on pHu, a* and C* parameters by canonical discriminant analysis., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

This study assessed the effect of breed and diet on carcass composition, particularly fat partitioning, and meat quality in young bulls. An experiment with forty young bulls from two phylogenetically distant Portuguese bovine breeds, Alentejana and Barrosã, fed two diets with different maize silage to concentrate ratios, but isoenergetic and isonitrogenous, was carried out until the animals reached 18 months of age. In the longissimus lumborum muscle, Barrosã bulls fed the low silage diet had the highest intramuscular fat (IMF) content. Bulls fed the low silage diet also had the highest IMF content in the semitendinosus muscle. Diet determined the proportions of total visceral fat and individual fat depots. Under these experimental conditions, it was shown that the genetic background is a major determinant of carcass composition and meat quality, and that the dietary differences studied had limited effect on carcass composition., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

1. Concentrations of beneficial omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) in poultry meat can be improved by increasing the concentration of n-3 PUFA in poultry diets. 2. A decrease in flavour quality is, however, usually associated with the dietary supplementation with n-3 PUFA, which is due to the susceptibility of PUFA to oxidation. 3. This experiment was conducted to study the effects of introducing two different n-3 fatty acid sources (extruded linseed and DHA Gold™, a proprietary algal product rich in docosahexaenoic acid), either separately or together, on broiler productive performance, and meat quality, oxidative stability, sensory traits and LC-PUFA profile. 4. Birds given the algal product displayed better productive performances than animals from other groups. 5. The data revealed an improvement in the fatty acid nutritional value of meat from birds receiving the algal product and an inefficient conversion of α-linolenic acid (LNA) into LC-PUFA. 6. Metabolisation of LNA in vivo is not sufficient to improve meat quality in n-3 LC-PUFA and direct supplementation of the diet with n-3 LC-PUFA is a better alternative to modulate an increase in beneficial fatty acids of broiler meat. 7. The overall acceptability of meat was negatively affected by the dietary supplementation with 7.4% of DHA, in contrast to the supplementation with 3.7% of DHA, which showed to be efficient in improving LC-PUFA meat content without affecting its sensory properties.

There is increasing evidence suggesting involvement of the renin-angiotensin system (RAS) in carbohydrate metabolism and its response to stress. Thus, the aim of the present study was to evaluate the effects of chronic inhibition of the RAS on glucose and insulin levels during acute restraint stress. Male Holtzman rats were treated with 10 mg/kg per day enalapril solution or vehicle for 14 days. After 14 days, rats were divided into three experimental groups: enalapril + restraint (ER), vehicle + restraint (VR) and enalapril + saline (ES). Rats in the restraint groups were subjected to 30 min restraint stress, whereas rats in the ES groups were given saline infusion instead. Blood samples were collected at baseline and after 5, 10, 20 and 30 min restraint stress or saline infusion. After restraint, a hyperglycaemic response was observed in the ER and VR groups that peaked at 20 and 10 min, respectively (P < 0.05 compared with baseline). The area under the glucose curve was markedly increased in the ER and VR groups compared with that in the ES group (P < 0.05 for both). Importantly, restraint induced a marked increase in insulin secretion in the ER group compared with only a mild elevation in the VR group; insulin secretion in both groups peaked at 20 min (P < 0.05 compared with baseline). Analysis of the area under the insulin curve confirmed an increase in insulin secretion in the ER compared with the VR and ES groups (P < 0.05 for both). The results of the present study reinforce that the RAS is involved in modulating responses to stress and suggest that RAS inhibition with enalapril may increase glucose-induced insulin secretion in response to acute restraint., (© 2012 The Authors Clinical and Experimental Pharmacology and Physiology © 2012 Wiley Publishing Asia Pty Ltd.)

This study investigated the effects of genotype and diet on meat fat composition and palatability obtained from Alentejana (AL) and Barrosã (BA) breeds. Herein, 20 males from each breed allocated at 11 months of age were fed ad libitum a low-forage diet or a high-forage diet and slaughtered at 18 months of age. Trained sensory panel analysis found that the longissimus lumborum (Ll) muscle from BA had higher tenderness, juiciness and overall acceptability scores than the AL breed. The highest scores for those attributes were observed in the BA breed fed the high-forage diet. Regarding the semitendinosus (St) muscle, breed was a source of variation of tenderness scores. In contrast to the Ll muscle, the highest tenderness scores for the St muscle were observed in the AL breed. The intramuscular fat (IMF) content was positively correlated with tenderness, juiciness and overall acceptability in Ll muscle and negatively correlated with flavour in the St muscle. The levels of 14:0 and 16:0, 16:1c9, 18:1c9 and 18:1c11 were positively correlated to juiciness, tenderness and overall acceptability in the Ll muscle. These correlations were not observed in the St muscle, which may be related to its low IMF content. Nonetheless, negative correlations were observed for the St muscle between flavour and 14:0, 16:0 and 18:0 FA contents.The IMF varied widely in the Ll but not in the St muscle. The latter had higher levels of 16:1c9 and trans fatty acids (∑TFA) in the BA than in the AL breed. Regarding the Ll muscle, the BA had higher amounts of 14:0, 16:0, 16:1c9, 18:0, 18:1c9, 18:1c11, saturated fatty acids (∑SFA), cis monounsaturated fatty acids (∑cis MUFA), ∑TFA and n-3 polyunsaturated fatty acids (∑n-3 PUFA) than the AL breed. The diet exerted an influence on the IMF content and on the levels of 14:0, 16:0, 16:1c9, 18:0, 18:1c9, 18:1c11, ∑SFA, ∑cis MUFA and ∑TFA in both Ll and St muscles. Moreover, the levels of ∑n-3 PUFA in the Ll muscle and 18:2n-6, 20:4n-6, ∑n-6 PUFA and ∑PUFA in the St muscle were influenced by diet. The results obtained in this study, with two Portuguese breeds, confirm that genetic background plays a major role in the determination of meat eating quality.

Consumer increasing demand for wild boar meat and scarceness of data on its lipid fraction justified this study. The psoas major muscle collected from 25 feral wild boars was used to quantify the total lipid, total cholesterol, fatty acid (FA) profile, and vitamin E homologues. Intramuscular fat and total cholesterol contents averaged 4.64 g/100g of meat and 56.9 mg/100g of meat, respectively. No differences were found in FA composition between groups, except for 20:5n-3 that was higher in youngsters. All groups presented small concentrations of rumenic acid in meat (CLA; 0.24% of total FA). FA profile showed considerable resemblance with pork, while the vitamin E profile is marked by high concentrations of both alpha- (17.4 ± 3.3 μg/g meat) and gamma-tocopherols (2.6 ± 1.3 μg/g meat) and by the presence of other vitamin E homologues not previously reported in wild boar meat., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

The selection of a muscle that could be used as an index muscle for beef tenderness was performed using nine commercially important muscles. A total of 50 bulls, Charolais×Alentejano (n=9), Simmental×Alentejano (n=9) and Alentejano (n=32), were slaughtered at two different commercial live weights: crossbred animals (sample A) between 500 and 600 kg (carcass weight between 310 and 370 kg) and purebred Alentejano (sample B) between 350 and 450 kg (carcass weight between 185 and 295 kg). Slaughter ages varied between 16 and 24 months in both groups. The shear force of nine muscles (Mm. biceps femoris, gastrocnemius, longissimus thoracis, longissimus lumborum, quadriceps femoris, semimembranosus, semitendinosus, supraspinatus and triceps brachii caput longum) was assessed seven days post-mortem. In both samples, the comparison between different muscle means and the combined mean of all muscles and the respective correlations showed that the Mm. biceps femoris and semimembranosus could be used as index muscles. However, the biceps femoris is preferred, because it showed greater stability in terms of the coefficient of variation.

There is an urgent need in industrialized societies to develop novel products that can lower human dietary cholesterol intake. Dehydrated alfalfa is a good source of hypocholesterolemic compounds such as saponins. Whether consumption of alfalfa by chickens would decrease the cholesterol content of broiler meat remains, however, to be established. We determined meat quality characteristics, lipid and cholesterol contents, and consumer preference of broiler meat derived from production systems based on restricted feeding of a commercial diet combined with provision of free-choice dehydrated alfalfa. Results demonstrated that it was possible to produce chicken breast meat with reduced cholesterol content. In addition, total lipids in chicken meat were significantly decreased when a higher level of restriction was applied. Members of a 50-person consumer panel preferred meat from animals not consuming or consuming moderate levels of alfalfa. Those members that preferred meat from animals consuming the higher percentage of alfalfa identified taste as the primary attribute influencing that decision. Together the results suggest that it is possible to develop novel broiler production systems that will produce leaner meat that is acceptable to consumers and has a reduced cholesterol content.