Open Access
Expression of key myogenic, fibrogenic and adipogenic genes in Longissimus thoracis and masseter muscles in cattle
(Cambridge University Press, 2020) Martínez del Pino, Lara; Urrutia Vera, Olaia; Arana Navarro, Ana; Alfonso Ruiz, Leopoldo; Mendizábal Aizpuru, José Antonio; Soret Lafraya, Beatriz; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Agronomía, Biotecnología y Alimentación
Adipogenesis, myogenesis and fibrogenesis are related processes that can contribute to meat quality. Therefore, extending the knowledge of these processes would facilitate the identification of molecular markers that predict intramuscular fat accretion. The main purpose of this work, based on previous results, was to further study the expression of key genes related to adipogenic, myogenic, fibrogenic processes and some cytokines in Longissimus thoracis (LT) and Masseter (MS) muscles of Pirenaica and Holstein young bulls. Longissimus thoracis and MS muscles from Pirenaica (n = 4) and Spanish Holstein (n = 4) were sampled for proximate analysis, determination of adipocyte size distribution and expression of key candidate genes. Fat percentage was lower in LT than in MS muscle in Pirenaica young bulls (P = 0.023) and was higher in LT muscle in Holstein than in Pirenaica young bulls (P = 0.007). Gene expression analysis revealed that the mRNA level of myogenic differentiation 1 (MYOD) was higher in LT than in MS muscles in both groups of animals (P < 0.001) and that myostatin (MSTN) expression was also higher in LT than in MS muscle in Holstein bulls (P = 0.001). On the other hand, MSTN and PPARG showed higher expression in LT and MS in Pirenaica young bulls (P = 0.026), while the expression of fatty acid-binding protein 4 (FABP4) was higher in Holstein young bulls, also in both muscles (P < 0.001). The results suggested that the development of intramuscular adipose depot was directly related to the expression of adipogenic genes, such as FABP4, but inversely related to the expression of the cytokine MSTN and the myogenic gene MYOD, genes which showed a muscle-specific expression.
Open Access
Insights into the role of major bioactive dietary nutrients in lamb meat quality: a review
(BMC, 2022) Álvarez-Rodríguez, Javier; Urrutia Vera, Olaia; Lobón, Sandra; Ripoll, Guillermo; Bertolín, Juan R.; Joy Torrens, Margalida; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura
Feed supplementation with α-linolenic acid (ALA) and linoleic acid (LA) increases their content in muscle, ALA increases n-3 polyunsaturated fatty acids and decrease n-6/n-3 ratio in muscle, and LA increases rumenic acid. However, high LA supplementation may have negative effects on lambs’ lipid oxidative stability of meat. When the sources of ALA and LA are fed as fresh forage, the negative effects are counterbalanced by the presence of other bioactive compounds, as vitamin E (mainly α-tocopherol) and polyphenols, which delay the lipid oxidation in meat. There is a wide consensus on the capability of vitamin E delaying lipid oxidation on lamb meat, and its feed content should be adjusted to the length of supplementation. A high dietary inclusion of proanthocyanidins, phenolic compounds and terpenes reduce the lipid oxidation in muscle and may improve the shelf life of meat, probably as a result of a combined effect with dietary vitamin E. However, the recommended dietary inclusion levels depend on the polyphenol type and concentration and antioxidant capacity of the feedstuffs, which cannot be compared easily because no routine analytical grading methods are yet available. Unless phenolic compounds content in dietary ingredients/supplements for lambs are reported, no specific association with animal physiology responses may be established.
Open Access
Preservation of milk in liquid nitrogen during sample collection does not affect the RNA quality for RNA-seq analysis
(BMC, 2025-05-24) Jiménez Montenegro, Lucía; Alfonso Ruiz, Leopoldo; Soret Lafraya, Beatriz; Mendizábal Aizpuru, José Antonio; Urrutia Vera, Olaia; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
Background. Standard procedures for milk sample collection for transcriptome analysis use ice as preservation method, which can afect the RNA stability and requires immediate sample processing. These problems would be eased if the milk samples could be snap-frozen in liquid nitrogen. This study describes the applicability of a new method for milk sample collection and subsequent RNA extraction from milk fat globules, determining whether the quality, integrity and quantity of the RNA extracts met the minimum requirements for downstream RNA-seq. Results. The quality of the extracts measured by A260/280 ratio and the Integrity and Quality (IQ) values obtained fulflled the reference values of 1.9 - 2.1 (P10.05) and failed to meet the RIN≥7 benchmark for RNA-seq (P>0.05). Milk fat globules contain low molecular-weight RNA fragments and minimal 18S and 28S rRNA, suggesting low RIN values were inherent to sample type. Likewise, the RNA concentration from milk fat globules were generally low (120.43±22.27 ng/µL, 102.87±15.64 ng/µL and 109.43±22.69 ng/µL, measured by Nanodrop, Qubit HS and QuanTI Ribogreen, respectively). Nevertheless, RNA-seq yielded 52.7 million paired-end reads per sample. The raw reads passed all quality control parameters having the same sequence-read lengths (151 bp), 100% base-coverage, 49% GC base content, and base quality scores of 36, enabling successful transcriptome profling. Moreover, milk proteins were identifed as the most abundant transcripts in MFG in the analysis of the most expressed genes, indicating that the sequenced reads would accurately refect the transcriptome of this milk fraction. Conclusions. Milk preservation in liquid nitrogen is a suitable sample collection method that overcomes the limitations of immediate sample processing required if ice is used. Thus, this procedure, together with the subsequent RNA isolation from milk fat globules and its sequencing by RNA-seq, would provide a practical and a non-invasive method for measuring the mammary epithelial cell transcriptome, improving the feasibility of conducting studies related to mammary gland and lactation physiology.
Open Access
Predicting beef carcass fatness using an image analysis system
(MDPI, 2021) Mendizábal Aizpuru, José Antonio; Ripoll, Guillermo; Urrutia Vera, Olaia; Insausti Barrenetxea, Kizkitza; Soret Lafraya, Beatriz; Arana Navarro, Ana; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
The amount and distribution of subcutaneous fat is an important factor affecting beef carcass quality. The degree of fatness is determined by visual assessments scored on a scale of five fatness levels (the SEUROP system). New technologies such as the image analysis method have been developed and applied in an effort to enhance the accuracy and objectivity of this classification system. In this study, 50 young bulls were slaughtered (570 ± 52.5 kg) and after slaughter the carcasses were weighed (360 ± 33.1 kg) and a SEUROP system fatness score assigned. A digital picture of the outer surface of the left side of the carcass was taken and the area of fat cover (fat area) was measured using an image analysis system. Commercial cutting of the carcasses was performed 24 h post-mortem. The fat trimmed away on cutting (cutting fat) was weighed. A regression analysis was carried out for the carcass cutting fat (y-axis) on the carcass fat area (x-axis) to establish the accuracy of the image analysis system. A greater accuracy was obtained by the image analysis (R2 = 0.72; p < 0.001) than from the visual fatness scores (R2 = 0.66; p > 0.001). These results show the image analysis to be more accurate than the visual assessment system for predicting beef carcass fatness.
Open Access
Development of a duplex qPCR assay with locked nucleic acid probes for A, B and E kappa-casein variants detection
(Springer Nature, 2022) Jiménez Montenegro, Lucía; Mendizábal Aizpuru, José Antonio; Alfonso Ruiz, Leopoldo; Azparren Domínguez, Leire; Urrutia Vera, Olaia; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Milk proteins determine important milk technological characteristics. Among caseins, Ƙ-casein has been correlated with fat and protein content and cheese yield. Fourteen Ƙ-caseins variants have been described but the alleles A, B and E are the most important ones due to their frequency and/or influence on the technological aptitudes of milk. Therefore, in the present study two different duplex qPCR assays with locked nucleic acid probes (for positions 13104 and 13124 of the Ƙ-casein gene) were developed for the detection of A, B and E variants. Firstly, DNA isolation method from milk somatic cells and hair was optimised. The developed 13124-qPCR assay showed an increased sensitivity reaching up to 6.7 copies DNA copies/reaction at a 95% confidence level with A, B and E alleles reference samples. The 13104-qPCR assay reached up to 6.7 DNA copies/reaction for A allele reference sample and 67 DNA copies/reaction for B and E samples. Intra-assay variation results were below 6%. Applicability was determined using DNA samples from animals with known genotype for Ƙ-casein (AA, AB, BB, BE, AE, EE) and both assays were able to discriminate among the six genotypes with 100% accuracy. Thus, this qPCR method represents a sensitive and rapid option for the detection of Ƙ-casein alleles in both hair and milk samples.
Open Access
Adipose tissue modification through feeding strategies and their implication on adipogenesis and adipose tissue metabolism in ruminants
(MDPI, 2020) Urrutia Vera, Olaia; Mendizábal Aizpuru, José Antonio; Alfonso Ruiz, Leopoldo; Soret Lafraya, Beatriz; Insausti Barrenetxea, Kizkitza; Arana Navarro, Ana; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Agronomía, Biotecnología y Alimentación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Dietary recommendations by health authorities have been advising of the importance of diminishing saturated fatty acids (SFA) consumption and replacing them by polyunsaturated fatty acids (PUFA), particularly omega-3. Therefore, there have been efforts to enhance food fatty acid profiles, helping them to meet human nutritional recommendations. Ruminant meat is the major dietary conjugated linoleic acid (CLA) source, but it also contains SFA at relatively high proportions, deriving from ruminal biohydrogenation of PUFA. Additionally, lipid metabolism in ruminants may differ from other species. Recent research has aimed to modify the fatty acid profile of meat, and other animal products. This review summarizes dietary strategies based on the n-3 PUFA supplementation of ruminant diets and their effects on meat fatty acid composition. Additionally, the role of n-3 PUFA in adipose tissue (AT) development and in the expression of key genes involved in adipogenesis and lipid metabolism is discussed. It has been demonstrated that linseed supplementation leads to an increase in alpha-linolenic acid (ALA) and eicosapentaenoic acid (EPA), but not in docosahexaenoic acid (DHA), whilst fish oil and algae increase DHA content. Dietary PUFA can alter AT adiposity and modulate lipid metabolism genes expression, although further research is required to clarify the underlying mechanism.
Open Access
Worldwide research trends on milk containing only A2 β-casein: a bibliometric study
(MDPI, 2022) Jiménez Montenegro, Lucía; Alfonso Ruiz, Leopoldo; Mendizábal Aizpuru, José Antonio; Urrutia Vera, Olaia; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
The protein fraction of β-casein may play a key role in the manifestation of a new intolerance: milk protein intolerance. The most common forms of β-casein among dairy cattle breeds are A1 and A2 β-casein. During gastrointestinal digestion of A1 β-casein, an opioid called peptide β-casomorphin-7 (BCM-7) is more frequently released, which can lead to adverse health outcomes. For that reason, novel products labelled as "A2 milk"or "A1-free dairy products" have appeared on the market. In this context, a bibliometric analysis on A2 β-casein research was carried out through the Web of Science (WoS) database. The main objective of this work was to provide an overview of the state of the art in the field of β-casein A2 by analyzing the number of publications per year, trends in thematic content, the most frequently used terms, and the most important institutions and countries in the field. This bibliometric study showed that a greater effort is needed to determine the possible implications of this novel product for human health and the market.
Open Access
Volatile compounds, odour and flavour attributes of lamb meat from the navarra breed as affected by ageing
(MDPI, 2021) Insausti Barrenetxea, Kizkitza; Urrutia Vera, Olaia; Mendizábal Aizpuru, José Antonio; Beriain Apesteguía, María José; Colle, Michael J.; Bass, Phillip D.; Arana Navarro, Ana; Murillo Arbizu, María Teresa; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
This study aimed to assess the influence of ageing on the volatile compounds, as well as odour and flavour attributes of lamb meat from the Navarra breed. Twenty-one male lambs were fed a commercial concentrate diet after weaning and were harvested at 101 ± 6.5 days of age. From the Longissimus thoracis, 26 volatile compounds were identified, with hexanal, 2-propanone, and nonanal the most abundant (57.17% relative percentage abundance, RPA). The effect of ageing (1 vs. 4 d) was observed (p < 0.05) in six compounds: 1,4-dimethylbenzene decreased with ageing, while tridecane, 3-methylbutanal, 2-heptanone, 3-octanone, and 1-octen-3-ol increased. In general, ageing was linked to a decrease in livery and bloody flavour, bloody odour and ethanal, and an increase in pentane, hexanal, and heptanal, which are usually associated with fresh green grass and fat descriptors. Consequently, ageing lamb from the Navarra breed for four days might have a positive effect on meat sensory odour and flavour quality.