Nonviral CRISPR/Cas9 mutagenesis for streamlined generation of mouse lung cancer models.

Functional analysis in mouse models is necessary to establish the involvement of a set of genetic variations in tumor development. A modeling platform to facilitate and cost-effectively analyze the role of multiple genes in carcinogenesis would be valuable. Here, we present an innovative strategy for lung mutagenesis using CRISPR/Cas9 ribonucleoproteins delivered via cationic polymers. This approach allows the simultaneous inactivation of multiple genes. We validate the effectiveness of this system by targeting a group of tumor suppressor genes, specifically Rb1, Rbl1, Pten, and Trp53, which were chosen for their potential to cause lung tumors, namely small cell lung carcinoma (SCLC). Tumors with histologic and transcriptomic features of human SCLC emerged after intratracheal administration of CRISPR/polymer nanoparticles. These tumors carried loss-of-function mutations in all four tumor suppressor genes at the targeted positions. These findings were reproduced in two different pure genetic backgrounds. We provide a proof of principle for simplified modeling of lung tumorigenesis to facilitate functional testing of potential cancer-related genes.

Cyclophosphamide-free mobilisation increases safety while preserving the efficacy of autologous haematopoietic stem cell transplantation in refractory Crohn's disease patients.

BACKGROUND AND AIM: Autologous haematopoietic stem cell transplantation [AHSCT] is a therapeutic option for refractory Crohn's disease [CD]. However, high adverse event rates related to chemotherapy toxicity and immunosuppression limit its applicability. This study aims to evaluate AHSCT's safety and efficacy using a cyclophosphamide (Cy)-free mobilisation regimen. METHODS: A prospective observational study included 14 refractory CD patients undergoing AHSCT between June 2017 and October 2022. The protocol involved outpatient mobilisation with G-CSF 12-16 µg/kg/daily for 5 days, and optional Plerixafor 240 µg/d (1-2 doses) if the CD34+ cell count target was unmet. Standard conditioning with Cy and anti-thymocyte globulin was administered. Clinical, endoscopic, and radiological assessments were conducted at baseline and during follow-up. RESULTS: All patients achieved successful outpatient mobilisation (7 patients needed Plerixafor) and underwent transplantation. Median follow-up was 106 weeks (IQR 52-348). No mobilisation-related serious adverse events (SAEs) or CD worsening occurred. Clinical and endoscopic remission rates were 71% and 41.7% at 26 weeks, 64% and 25% at 52 weeks, and 71% and 16.7% at the last follow-up. The percentage of patients who restarted CD therapy for clinical relapse and/or endoscopic/radiological activity was 14% at 26 weeks, 57% at 52 weeks, and 86% at the last follow-up. Peripheral blood cell populations and antibody levels post-AHSCT were comparable to Cy-based mobilisation. CONCLUSIONS: Cy-free mobilisation is safe and feasible in refractory CD patients undergoing AHSCT. Although relapse occurs in a significant proportion of patients, clinical and endoscopic responses are achieved upon CD-specific therapy reintroduction.

Magnetic resonance enterography findings 46 weeks after initiation of biological therapy predict long-term adverse outcomes in Crohn's disease.

BACKGROUND AND AIMS: Magnetic resonance enterography (MRE) depicts transmural changes in response to biological treatment for Crohn's disease (CD); however, the long-term prognostic significance of these findings is unknown. The primary objective of this study was to identify findings on MRE 46 weeks after initiating biological treatment that predict adverse long-term outcomes. METHODS: Patients with CD underwent MRE 46 weeks after initiating biological treatment and were prospectively followed for 2 years. A logistic regression analysis was performed to assess the prognostic value of different radiologic findings for various predefined adverse outcomes. RESULTS: Of the 89 patients included, 46 (51.7%) had ≥1 adverse outcome during follow-up: 40 (44.9%) had clinical recurrence; 18 (20.2%) required surgery, 8 (9%) endoscopic balloon dilation, 12 (13.5%) hospitalization and 7 (7.8%) required corticosteroids. In the multivariate analysis, persistence of severe lesions (MaRIA ≥11) in any intestinal segment was associated with an increased risk of surgery [OR 11.6 (1.5-92.4)], of surgery and/or endoscopic balloon dilation [OR 6.3 (1.3-30.2)], and of clinical relapse [OR 4.6 (1.6-13.9)]. Penetrating lesions were associated with surgery [OR 3.4 (1.2-9.9)]. Creeping fat with hospitalization [OR 5.1 (1.1-25.0)] and corticosteroids requirement [OR 16.0 (1.2-210.0)]. The presence of complications (stricturing and/or penetrating lesions) was associated with having ≥1 adverse outcome [OR 3.35 (1.3-8.5)]. CONCLUSION: MRE findings at week-46 after initiating biological therapy can predict long-term adverse outcomes in CD. Therapeutic intervention may be required in patients with persistence of severe inflammatory lesions, CD-associated complications, or creeping fat.

ADC Values for Detecting Bowel Inflammation and Biologic Therapy Response in Patients With Crohn Disease: A Post Hoc Prospective Trial Analysis.

BACKGROUND. New biologic agents for Crohn disease (CD) create a need for noninvasive disease markers. DWI may assess bowel inflammation without contrast agents. OBJECTIVE. The purpose of this study was to evaluate ADC values for identifying bowel inflammation and therapeutic response in patients with CD treated with biologic therapy. METHODS. This study entailed post hoc analysis of prospective trial data. Analysis included 89 patients (median age, 37 years; 49 women, 40 men) with CD treated by biologic therapy who underwent MR enterography (MRE) at baseline and 46 weeks after therapy, from March 2013 to April 2021; 43 patients underwent ileocolonoscopy at both time points. Analysis was conducted at the level of small-bowel and colorectal segments (586 segments analyzed). MR index of activity (MaRIA) score and presence of endoscopic ulcers were determined at both time points. One observer measured bowel wall ADC. Diagnostic performance was evaluated. Dichotomous ADC assessments used a threshold of 1301 × 10-6 mm2/s based on initial ROC analysis; dichotomous MaRIA score assessments used a threshold of 11 (moderate to severe inflammation). A second observer repeated ADC measurements in 15 patients. RESULTS. At baseline, ADC had AUC of 0.92, sensitivity of 78.6%, specificity of 91.4%, and accuracy of 88.2% for detecting segments with MaRIA score 11 or greater. At baseline, AUC for detecting endoscopic ulcers was 0.96 for MaRIA score versus 0.87 for ADC (p < .001); sensitivity, specificity, and accuracy were 70.8%, 90.2%, and 85.1% for ADC and 86.2%, 96.2%, and 93.6% for MaRIA score. At follow-up, ADC had AUC of 0.87, sensitivity of 75.4%, specificity of 83.6%, and accuracy of 80.0% for detecting improvement in MaRIA score to less than 11. At follow-up, AUC for detecting endoscopic ulcer healing was 0.94 for MaRIA score versus 0.84 for ADC (p = .01); sensitivity, specificity, and accuracy were 70.7%, 95.8%, and 84.4% for ADC and 90.2%, 100.0%, and 95.6% for MaRIA score. Interobserver agreement for ADC, based on intraclass correlation coefficient, was 0.70 at baseline and 0.65 at follow-up. CONCLUSION. The findings do not support use of ADC rather than MaRIA scores for detecting biologic therapy response. CLINICAL IMPACT. ADC may have an adjunct role in assessing bowel inflammation in CD, but showed limited performance for detecting biologic therapy response.

Vacuum impregnation as a sustainable technology to obtain iron-fortified broad bean (Vicia faba) flours.

Iron-fortified broad bean flours were obtained by vacuum impregnation during soaking. The impact of vacuum impregnation and iron fortification on the hydration kinetics of broad beans, as well as the processing (soaking, autoclaving, and dehulling) on the iron-absorption inhibitors (phytic acid and tannins), iron content, iron bioaccessibility, and physicochemical and techno-functional properties of flours was investigated. Results showed that the use of vacuum impregnation during soaking reduced the broad beans' soaking time by 77%, and using iron solution instead of water did not affect the hydration kinetics. After soaking, iron-fortified broad bean flours increased twice (without hull) or more (with hull) the iron and bioaccessible iron content regarding non-fortified flours. Cooking broad beans by autoclaving modified the tannin content, the iron content and its bioaccessible fraction, and the physicochemical and techno-functional properties of the flours. Autoclaving increased the water holding capacity and absorption rate, swelling capacity, bulk density, and particle size, while decreased the solubility index, whiteness index, emulsifying capacity, emulsion stability, and gelling capacity. Finally, dehulling did not practically affect the physicochemical and techno-functional properties of flours, but showed a decrease in iron content, although increased iron bioaccessibility was observed, occurred mainly due to the reduction in tannin concentrations. The results obtained in this study demonstrated that vacuum impregnation is a useful technology for obtaining iron-fortified broad bean flours with different physicochemical and techno-functional properties depending on the production process used.

Impact of thermal treatments and simulated gastrointestinal digestion on the α-amylase inhibitory activity of different legumes.

Legumes are excellent sources of proteins that can be hydrolysed to generate antidiabetic peptides, which inhibit carbohydrate digestive enzymes. The degree of protein hydrolysis depends on the thermal treatment applied and how it impacts protein denaturation and thus accessibility to enzymes. In this study, α-amylase inhibitory activities of cooked (conventional, pressure, and microwave cooking) and digested (simulated gastrointestinal digestion, GID) green pea, chickpea, and navy beans were evaluated, together with the impact of thermal treatments on peptide profiles after GID. All peptides extracts inhibited α-amylase after cooking and GID, and the peptide fraction <3 kDa was responsible for main activity. In green peas and navy beans, microwave cooking showed the highest impact whereas none thermal treatment highlighted in chickpeas. The peptidomics analysis of the fractions <3 kDa identified a total of 205 peptides, 43 of which were found to be potentially bioactive according to in silico analysis. Also quantitative results evidenced differences in the peptide profile between the type of legume and thermal treatment.

Accuracy and Limitations of Sentinel Lymph Node Biopsy after Neoadjuvant Chemotherapy in Breast Cancer Patients with Positive Nodes.

Background: Axillary surgical management in patients with node-positive breast cancer at the time of diagnosis converted to negative nodes through neoadjuvant chemotherapy (NAC) remains unclear. Removal of more than two sentinel nodes (SLNs) in these patients may decrease the false negative rate (FNR) of sentinel lymph node biopsies (SLNBs). We aim to analyse the detection rate (DR) and the FNR of SLNB assessment according to the number of SLNs removed. Methods: A retrospective study was performed from October 2012 to December 2018. Patients with invasive breast cancer who had a clinically node-positive disease at diagnosis and with a complete axillary response after neoadjuvant chemotherapy were selected. Patients included underwent SLNB and axillary lymph node dissection (ALND) after NAC. The SLN was considered positive if any residual disease was detected. Descriptive statistics were used to describe the clinicopathologic features and the results of SLNB and ALND. The DR of SLNB was defined as the number of patients with successful identification of SLN. Presence of residual disease in ALND and negative SLN was considered false negative. Results: A total of 368 patients with invasive breast cancer who underwent surgery after complete NAC were studied. Of them, 85 patients met the eligibility criteria and were enrolled in the study. The mean age at diagnosis was 50.8 years. Systematic lymphadenectomy was performed in all patients, with an average of 10 lymph nodes removed. The DR of SLNB was 92.9%, and the FNR was 19.1. The median number of SLNs removed was 3, and at least, three SLNs were obtained in 42 patients (53.2%). When at least three sentinel nodes were removed, the FNR decreased to 8.7%. Conclusions: In this cohort, the SLN assessment was associated with an adequate DR and a high FNR. Removing three or more SLNs decreased the FNR from 19.1% to 8.7%. Complementary approaches may be considered for axillary lymph node staging after neoadjuvant chemotherapy. The study was approved by our institution's ethics committee (Instituto de Investigacion Sanitaria Hospital 12 de Octubre (imas12), Universidad Complutense de Madrid, Madrid, Spain) (https://clinicaltrials.gov/ct2/show/NCEI:20/0048).

Guiding the global evolution of cytogenetic testing for hematologic malignancies.

Cytogenetics has long represented a critical component in the clinical evaluation of hematologic malignancies. Chromosome banding studies provide a simultaneous snapshot of genome-wide copy number and structural variation, which have been shown to drive tumorigenesis, define diseases, and guide treatment. Technological innovations in sequencing have ushered in our present-day clinical genomics era. With recent publications highlighting novel sequencing technologies as alternatives to conventional cytogenetic approaches, we, an international consortium of laboratory geneticists, pathologists, and oncologists, describe herein the advantages and limitations of both conventional chromosome banding and novel sequencing technologies and share our considerations on crucial next steps to implement these novel technologies in the global clinical setting for a more accurate cytogenetic evaluation, which may provide improved diagnosis and treatment management. Considering the clinical, logistic, technical, and financial implications, we provide points to consider for the global evolution of cytogenetic testing.

Effect of cooking and in vitro digestion on the peptide profile of chicken breast muscle and antioxidant and alcohol dehydrogenase stabilization activity.

The present study aimed to investigate the effect of cooking and simulated gastrointestinal digestion on the antioxidant and alcohol dehydrogenase (ADH) stabilization activity of peptides extracted from chicken breast muscle. Results showed that cooking would not affect peptide bioactivity, whereas further digestion using gastrointestinal enzymes could lead to significant changes, producing an increase in ORAC (112.5 to 682.0 uM TE/g) and ABTS radical scavenging activities (164.0 to 848.9 uM TE/g), whereas a decrease in DPPH radical scavenging (from 36.1% to 4.4%), ferric-reducing power (OD 700 from 0.50 to 0.15) and ADH stabilization activities (from 44.1% to 20.5%) was observed. The peptidomic analysis resulted in the identification and relative quantitation of 777 peptides from 76 different parent proteins and evidenced that peptides derived from titin and collagen were mainly responsible for the differences detected in the peptide profile. The decrease of DPPH radical scavenging, ferric reducing power, and ADH stabilization activity may result from the release of inactive peptides containing oxidized residues, mainly from collagen, leading to the loss of efficacy of active sequences. The results confirmed the importance of collagen derived peptides on the antioxidant and ADH stabilization activity observed in chicken breast as well as the negative impact of oxidation on the bioactivity of generated peptides after simulated gastrointestinal digestion. Nevertheless, further work would be needed to confirm the peptide sequences responsible for the observed bioactivity.

Evaluation of main post-translational modifications occurring in naturally generated peptides during the ripening of Spanish dry-cured ham.

Peptidyl post-translational modifications (PTMs) could influence the final quality of processed meat. In this study, the peptide oxidative phenomena in Spanish dry-cured ham (Biceps femoris muscle) was evaluated at different ripening times (9, 12, 15, 18 and 24 months of processing) evidencing interactions amongst the lipid and protein oxidation, major peptidyl PTMs and the release of free amino acids (FAAs). Results showed that 12 months of processing enabled the most abundant protein-bound carbonyls, while TBARS value was significantly favored (p < 0.001) by ripening. However, FAAs were still intensively generated during overall ripening. Peptidomics and chemometrics further revealed that proteolysis mostly hampered the oxidized peptides rather than the deamidated ones during ripening. Myosin light chain (MYL1 and MYL3) showed high oxidative susceptibility owing to peptidyl methionine and proline oxidation as well as acetaldehyde adduct formation on lysine or histidine residues.

Effect of Gelatin Coating Enriched with Antioxidant Tomato By-Products on the Quality of Pork Meat.

The use of edible biopolymers and natural additives obtained from food processing by-products is a sustainable strategy for food packaging applications. Gelatin is a biopolymer with great potential as a coating due to its low cost, high availability, and technological and functional properties. Among them, gelatin can be used as a carrier of bioactive compounds such as antioxidants, which can retard oxidation processes and thus extend the shelf-life of highly-perishable products. This study evaluated the effect of gelatin coating enriched with antioxidant tomato by-products hydrolysate (TBPH) on the quality of pork meat during cold storage. Results showed that TBPH obtained from Alcalase hydrolysis presented antioxidant activity with good stability against cooking. Additionally, chromatographic and mass spectrometry techniques, as well as in silico analysis, were used for the peptidomic characterisation of TBPH. The application of enriched gelatin coating on meat led to some physicochemical changes including increased weight loss and colour differences; however, the pH and water activity, which control meat spoilage, were maintained during storage. Moreover, coating prevented lipid oxidation of meat, and enriched-coated meat presented high antioxidant activity after cooking. These results suggest the positive role of gelatin coating enriched with TBPH in extending the shelf-life of meat during storage.

Bioactive peptides generated in the processing of dry-cured ham.

Peptides and free amino acids are naturally generated in dry-cured ham as a consequence of proteolysis phenomenon exerted by muscle peptidases. The generation of bioactive peptides in different types of dry-cured ham produced in Spain, Italy and China is reviewed in this manuscript. Major muscle proteins are extensively hydrolysed firstly by endogenous endo-peptidases followed by the successive action of exo-peptidases, mainly, tri- and di-peptidylpeptidases, aminopeptidases and carboxypeptidases. Such proteolysis is very intense and consists of the generation of large amounts of free amino acids and a good number of peptides with different sequences and lengths, some of them exerting relevant bioactivities like angiotensin converting enzyme inhibitory activity, antioxidant activity, di-peptidylpeptidase IV inhibitory activity among other and in vivo antihypertensive, hypoglycemic or anti-inflammatory activity. This manuscript reviews the recent findings showing that dry-cured ham constitutes a good source of natural bioactive peptides that have potential benefit for human health.

Recent Progress in Enzymatic Release of Peptides in Foods of Animal Origin and Assessment of Bioactivity.

There is a wide variety of peptides released from food proteins that are able to exert a relevant benefit for human health, such as angiotensin-converting enzyme inhibition, antioxidant, anti-inflammatory, hypoglucemic, or antithrombotic activity, among others. This manuscript is reviewing the recent advances on enzymatic mechanisms for the hydrolysis of proteins from foods of animal origin, including the types of enzymes and mechanisms of action involved, the strategies followed for the isolation and identification of bioactive peptides through advanced proteomic tools, and the assessment of bioactivity and its beneficial effects. Specific applications in fermented and/or ripened foods where a significant number of bioactive peptides have been reported with relevant in vivo physiological effects on laboratory rats and humans as well as the hydrolysis of animal food proteins for the production of bioactive peptides are also reviewed.

Development and validation of the QUECOMIICAT questionnaire: a tool to assess disease-related knowledge in patients with inflammatory bowel disease.

INTRODUCTION: adequate knowledge of inflammatory bowel disease (IBD) is essential for a successful patient-centered management of IBD. OBJECTIVE: due to the scarcity of up-to-date tools for measuring IBD literacy, this single-center, prospective study aimed to develop and validate a new questionnaire to assess IBD-related knowledge. MATERIAL AND METHODS: the study included patients followed up at the Crohn-Colitis Care Unit (UACC) at the Hospital Vall d'Hebron (Barcelona, Spain). Patients admitted to the UACC for the first time were subsequently enrolled into a standard IBD educational program. A pilot questionnaire was developed and validated in 92 IBD patients by determining the internal consistency reliability (Cronbach's α test), feasibility, construct validity (correlation with the Crohn's and Colitis Knowledge [CCKNOW] questionnaire and a knowledge visual analog scale [VAS]) and sensitivity (score change before and after a standard IBD educational program). The questionnaire, named "Qüestionari Coneixements Malaltia Inflamatòria Intestinal Catalunya" (IBD-knowledge questionnaire Catalonia) (QUECOMIICAT) was written in Spanish and had 25 items addressing six dimensions: general concepts, clinic, treatment, surgery, habits and social context. RESULTS: the median (interquartile range) completion time was 15 (10-20) minutes and the floor and ceiling effects were 1.1% and 2.1%, respectively. The Cronbach's α coefficient was α = 0.75. QUECOMIICAT significantly correlated with the VAS (rho = 0.34, p < 0.01) and CCKNOW questionnaires (rho = 0.74, p < 0.01). Patient knowledge significantly increased 24 hours after attending a standard IBD educational program and remained statistically significant one month later (Pearson's test-retest correlation coefficient r = 0.81, p < 0.001). CONCLUSION: in conclusion, the QUECOMIICAT questionnaire is a new up-to-date tool to assess IBD-related knowledge with good feasibility and validation results for use in the routine clinical practice.

Development and Validation of a Simplified Magnetic Resonance Index of Activity for Crohn's Disease.

BACKGROUND & AIMS: The magnetic resonance index of activity (MARIA) for Crohn's disease (CD) is used to assess the activity of luminal CD. However, it has a number of practical limitations. We aimed to develop and validate a simplified MARIA to more easily and quickly assess CD activity and response to therapy. PATIENTS AND METHODS: We performed a retrospective analysis of magnetic resonance imaging data from 98 participants in 2 studies. We used logistic regression analysis to identify magnetic resonance imaging parameters independently associated with CD endoscopic index of severity (CDEIS) scores (the reference standard). We validated the responsiveness and reliability of the simplified MARIA in an independent cohort of 37 patients who underwent magnetic resonance imaging and endoscopy before and after a therapeutic intervention. RESULTS: Logistic regression analysis showed that dichotomous qualitative assessment of wall thickening (>3 mm), presence of mural edema, perienteric fat stranding, and ulcers were independently associated with CDEIS scores; we used these factors to create a simplified MARIA. Simplified MARIA scores greater than 1 identified segments with active CD with 90% sensitivity and 81% specificity (area under the curve 0.91; 95% confidence interval 0.88-0.94). Simplified MARIA scores of 2 or more detected severe lesions (ulcers) with 85% sensitivity and 92% specificity (area under the curve 0.94; 95% confidence interval 0.91-0.96). For each patient, there was a high level of correlation between simplified MARIA scores and CDEIS scores (r = 0.83) and simplified MARIA scores and original MARIA scores (and r = 0.93) (P < .001). The simplified MARIA score accurately detected changes in lesion severity in response to therapy and was as reliable as endoscopy for the assessment of mucosal healing. CONCLUSION: We developed and validated a simplified MARIA for easier and faster assessment of CD activity and severity. This index identifies patients with a response to therapy with a high level of accuracy. These findings require confirmation in independent, multireader studies.

Endoscopic response to tumor necrosis factor inhibitors predicts long term benefits in Crohn's disease.

BACKGROUND: Identifying predictors of therapeutic response is the cornerstone of personalized medicine. AIM: To identify predictors of long-term mucosal healing (MH) in patients with Crohn's disease (CD) treated with tumor necrosis factor α (TNF-α) inhibitors. METHODS: Prospective single center study. Consecutive patients with clinically active CD requiring treatment with a TNF-α inhibitor were included. A baseline segmental CD Endoscopic Index of Severity (CDEIS) ≥ 10 in at least one segment or the presence of ulcerations were required for inclusion. Clinical, biological and endoscopic data were obtained at baseline, weeks 14 and 46. Endoscopic response (ER) was defined as a decrease ≥ 50% from baseline CDEIS and MH as partial CDEIS ≤ 5 in all segments. RESULTS: Of 62 patients were included. At baseline, median CD Activity Index and CDEIS were 201 and 6.7, respectively with a significant reduction after one year of treatment (53 and 3.0 respectively, P < 0.001). At week 14, 56% of patients achieved ER and 34% MH. At week 46, the corresponding percentages were 52% and 44%. Baseline disease characteristics or biomarkers did not predict MH. A decrease from baseline CDEIS at week 14 of at least 80% was the best predictor of MH at week 46 (59% sensitivity and 91% specificity; area under the curve = 0.778). CONCLUSION: Clinical and biomarker data are not useful predictors of response to TNF-α inhibitors in CD, whereas ER to induction therapy, defined as 80% reduction in global CDEIS, is a robust predictor of long-term MH. Achievement of this endoscopic endpoint may be considered as a therapeutic target for anti-TNF-α therapy.

Peptides with Potential Cardioprotective Effects Derived from Dry-Cured Ham Byproducts.

The interest in using food byproducts as a source of bioactive peptides has increased significantly in the recent years. The goal of this work was to determine the presence and stability of peptides showing angiotensin I-converting enzyme (ACE-I), endothelin-converting enzyme (ECE), dipeptidyl peptidase-IV (DPP-IV), and platelet-activating factor-acetylhydrolase (PAF-AH) inhibitory activity derived from dry-cured ham bones, which could exert cardiovascular health benefits. ACE-I and DPP-IV inhibitory peptides were stable against heating typically used in Mediterranean household cooking methods and also to in vitro digestion. PAF-AH inhibitory activity significantly increased following simulated gastrointestinal digestion whereas ECE inhibitory significantly decreased ( P < 0.05). The mass spectrometry analysis revealed a notable degradation of hemoglobin-derived peptides after simulated digestion, and the release of a large number of dipeptides that may have contributed to the observed bioactivities. These results suggest that natural peptides from Spanish dry-cured ham bones could contribute to a positive impact on cardiovascular health.

ACEI-Inhibitory Peptides Naturally Generated in Meat and Meat Products and Their Health Relevance.

Meat and meat products have been described as a very good source of angiotensin I converting enzyme (ACEI)-inhibitory peptides. The generation of bioactive peptides can occur through the action of endogenous muscular enzymes during processing, gastrointestinal digestion, or by using commercial enzymes in laboratory or industry under controlled conditions. Studies of bioavailability are necessary in order to prove the positive health effect of bioactive peptides in the body as they should resist gastrointestinal digestion, cross the intestinal barrier, and reach blood stream and target organs. However, in order to better understand their effect, interactions, and bioavailability, it is necessary to consider food matrix interactions and continue the development of quantitative methodologies in order to obtain more data that will enable advances in the field of bioactive peptides and the determination of their influence on health.

Differences in peptide oxidation between muscles in 12 months Spanish dry-cured ham.

Oxidative modifications of proteins and peptides can negatively affect nutritional, sensory and quality characteristics of dry-cured hams. The aim of this study was to use a peptidomics strategy for the identification and relative quantification of oxidised peptides in two different muscles, the external Semimembranosus (SM) and the internal Biceps femoris (BF), from dry-cured hams of 12 months of curing. The analysis by nanoliquid chromatography-tandem mass spectrometry identified peptides showing oxidation at different amino acid residues such as methionine, cysteine, histidine, tryptophan, and phenylalanine. The highest percentages of oxidised peptides identified in SM and BF muscles were from pyruvate kinase protein (16.7 and 28.6%, respectively). The relative quantitation of oxidised peptides using mass spectrometry in tandem label-free methodology evidenced significant differences between muscles, with myosin and troponin fragments as main responsible peptides for the clustering of data. The existing differences between BF and SM peptides were confirmed using MALDI imaging mass spectrometry technique. The obtained results suggest that differences in physicochemical characteristics such as water and salt contents between SM and BF muscles could affect the quantity of peptide oxidation. This peptidomics approach has allowed to analyse differences in peptide oxidation between dry-cured ham muscles as well as to improve the knowledge about the oxidative processes that occur in dry-cured hams.