María Josefa Rodríguez-Colunga

University of Oviedo, Oviedo, Asturias, Spain

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Publications (52)209.33 Total impact

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    ABSTRACT: The Syrian hamster Harderian gland (HG) has a marked sexual dimorphism and exhibits an extraordinary rate of porphyrinogenesis. The physiological oxidative stress, derived from constant porphyrin production, is so high that the HG needs additional survival autophagic mechanisms to fight against this chronic exposure, provoking the triggering of a holocrine secretion in female glands that forms two types of secretory masses: intra-tubular-syncytial and inter-tubular-syncytial masses. The aim of this work was to study the development of this inter-tubular holocrine secretion. To approach this task, we have considered that the steps developed during the formation of the so-called invasive masses consist of the growth of epithelial cells, cell detachment from the basal lamina and invasion of surrounding tissues. The presence of these masses, particularly in the female HG, are closely linked to sexual dimorphism in redox balance and to alterations in the expression of certain factors such as cytokeratins, P-cadherin, matrix metalloproteinases, cathepsin H, proliferating cell nuclear antigen, p53, CD-31 and vascular endothelial growth factor, which seem to be involved in tissue remodeling. The results document unusual mechanisms of secretion in Syrian hamster HG: an extraordinary system of massive secretion through the conjunctive tissue, disrupting the branched structure of the gland.
    Journal of Anatomy 03/2013; · 2.36 Impact Factor
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    ABSTRACT: PurposeThe aim of this investigation was to analyze whether the following platelet indices are useful markers for functional dependence and 1-year all-cause hospitalization and mortality in the elderly population: platelet count (PLT), platelet distribution width (PDW), mean platelet volume (MPV), and platelet–large cell ratio (P-LCR).Methods The 119 participants in this study were 90 women and 29 men between the ages of 68 and 105 years who were selected from the Santa Teresa nursing home (Oviedo, Spain). We studied morbidity, sociodemographic characteristics, and functional status using the Barthel Index (BI) and Katz Index (KI) for activities of daily living.ResultsIn logistic regression models adjusted for age, sex, and anti-inflammatory drug use, low levels of PDW were associated with death at 1 year. When we applied logistic regression models adjusted for morbid conditions as well as age, sex, and anti-inflammatory drug use, the PDW remained statistically significant. No relation between PLT, MPV, or P-LCR and mortality was found. No statistical associations between the platelet indices studied and functional dependence or hospitalization were observed.Conclusion Our data suggest that the PDW could be a predictor of 1-year mortality in the elderly population and may therefore serve as a useful tool for identifying individuals with a high risk of mortality who may benefit from preventative care or early-stage strategies.
    Journal of Clinical Gerontology and Geriatrics. 03/2013; 4(1):12–16.
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    ABSTRACT: Eur J Clin Invest 2012; 42 (10): 1037-1046 ABSTRACT: Background  Systemic low-grade inflammation is thought to be associated with an increased risk of adverse clinical outcomes in elderly population. We tested this notion with the goal of identifying useful potential biomarkers of 1-year hospitalization and mortality in the elderly population. Design  A total of 120 institutionalized older subjects were enrolled as participants in this study, including 90 women and 30 men (ranging in age from 68 to 105 years), selected from Santa Teresa nursing home (Oviedo, Spain). We studied functional status, morbidity, socio-demographic characteristics and several inflammation and inflammation-related markers. Results  The study included 95 non-hospitalized participants and 23 participants with at least one hospitalization during 1 year (19% of subjects). The study also included 100 survivors and 19 participants who died during the 1-year study (16% of subjects). In logistic regression models adjusted by age, sex, anti-inflammatory drug use and morbid conditions, high levels of interleukin 1 receptor antagonist (IL-1ra) and red blood cell distribution width (RDW) were associated with hospitalization and death at 1 year. Elevated levels of tumour necrosis factor α (TNF-α) were also associated with an increased risk of death at 1 year after adjusting for the same potential confounders. Multivariate logistic regression models showed that elevated serum levels of IL-1ra were intimately associated with 1-year subsequent hospitalization and mortality in aged subjects after adjusting for age, sex, anti-inflammatory drug use and morbid conditions. Conclusions  Current data suggest that IL-1ra is a predictor of 1-year hospitalization and mortality in the elderly population.
    European Journal of Clinical Investigation 04/2012; 42(10):1037-46. · 3.37 Impact Factor
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    ABSTRACT: In the present investigation we have analyzed the association between functional dependence and inflammatory biomarkers using the Barthel Index (BI) and the Katz Index (KI). This analysis may contribute to translational medicine by incorporating the clinical and laboratory data to better understand the relationship between chronic inflammation and functional dependence in the elderly population. The ultimate goal of this study was to identify possible useful biomarkers of functional dependence in the elderly. Participants in this study consisted of 120 older subjects (90 women and 30 men; range 68-105 years) who were selected from the Santa Teresa nursing home (Oviedo, Spain). We studied functional status using the following tools to diagnose the functional dependence by clinicians: BI and KI for activities of daily living. We analyzed morbidity, sociodemographic characteristics and a panel of inflammatory and inflammatory-related markers. In linear regression models adjusted by age, sex, anti-inflammatory drug use and morbid conditions high levels of interleukin 6 (IL-6) and soluble TNF receptor-I (sTNF-RI) were associated with functional dependence as measured using BI and KI. Elevated levels of red blood cell distribution width (RDW) were also associated with functional dependence measured using the KI after adjusting for the same potential confounders. The current results suggest that high IL-6, sTNF-RI and RDW levels are associated with the functional dependence in the elderly population. The results are consistent with the presumed underlying biological mechanism, in which the up-regulation of inflammatory mediators is associated with functional dependence in elderly subjects.
    Cytokine 02/2012; 58(2):193-8. · 2.52 Impact Factor
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    ABSTRACT: The objective of the present study was to investigate a large panel of oxidative stress biomarkers in long-term trained elderly men to analyse the effects of chronic training on an aged population. We collected blood samples from two groups of male volunteers older than 65 years who maintain a measure of functional independence: one group of sedentary subjects without a history of regular physical activity and the other of subjects who have sustained training, starting during middle age (mean training time = 49 ± 8 years). We studied morbidity and polypharmacy, as well as haematological parameters including red cell count, haemoglobin concentration, haematocrit, mean corpuscular volume, red cell distribution width and several oxidative biomarkers including protein carbonyl content and lipid peroxidation in plasma and erythrocytes, red blood cell H(2)O(2)-induced haemolysis test, plasma total antioxidant activity and the main antioxidant enzymes of erythrocytes: superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase. After adjusting for confounding factors, we observed an increase in all oxidative damage biomarkers in the plasma and erythrocytes of the long-term exercise group. However, we reported a decrease in the number of diseases per subject with statistical differences nearly significant (p = 0.061), reduced intake of medications per subject and lower levels of red cell distribution width in the chronic exercise group. These results indicate that chronic exercise from middle age to old age increases oxidative damage; however, chronic exercise appears to be an effective strategy to attenuate the age-related decline in the elderly.
    Age 01/2012; · 6.28 Impact Factor
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    ABSTRACT: Studies of the role of oxidative stress in functional dependence among the aging population are limited. In this report, we address this situation through an analysis of a large panel of blood oxidative biomarkers in elderly population. Because the analysis of multiple biomarkers increases the complexity of data interpretation, this investigation has utilized both an analysis of single biomarkers in addition to employment of the statistical data reduction tool principal component analysis that might allow for a clearer description of redox status as compared with a single measure alone. We studied three groups of participants older than 65 years based on their Barthel Index: an independent group (100-95), a moderately dependent group (94-60), and a severely dependent group (59-0). We observed a significant increase in circulating protein carbonyl levels in the severely dependent group as compared with the independent and moderately dependent groups. Using principal component analysis, we found at least three factors (an erythrocyte-related component, a protein damage-related component, and a plasma-related component) that could be used to assess the different oxidative parameters in our population. We discovered a significant association of higher levels of the protein damage-related component with the severely dependent group. Protein damage levels could be assessed in clinical use as a biomarker of severe dependence. Furthermore, our results support the hypothesis that functional decline could be associated in part due to oxidative stress. Finally, we show that principal component analysis could be a useful statistical tool in the analysis of age-related decline.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 12/2011; 67(6):663-70. · 4.31 Impact Factor
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    ABSTRACT: The Syrian hamster Harderian gland exhibits sexually dimorphic porphyrin biosynthesis, wherein the female glands display an extraordinarily high concentration of porphyrins. Damage derived from this production of porphyrins, mediated by reactive oxygen species, causes the glands to develop autophagic processes, which culminate in detachment-derived cell death; these cells normally play a central role in the secretory activity of the gland. The main aim of this study was to analyze how a change in the redox state impacts autophagy. Female Syrian hamsters were treated daily with melatonin (25 μg, subcutaneously) at ZT 10 for 1-2 months (N-acetyl-5-methoxytryptamine), an endogenous antioxidant that ameliorates the deleterious effects of free radicals via a variety of mechanisms. The length of treatment affected the redox balance, the autophagy machinery, and the activation of p53 and NF-κB. One-month treatment displaces redox balance to the antioxidant side, promotes autophagy through a p53-mediated mechanism, and increases cell detachment. Meanwhile, 2-month treatment restores redox balance to the oxidant side, activates NF-κB reducing autophagy to basal levels, increases number of type II cells, and reduces number of detached cells. Our results conclude that the redox state can modulate autophagy through redox-sensitive transcriptions factors. Additionally, these findings support a hypothesis that ascribes differences in the autophagic-lysosomal pathway to epithelial cell types, thereby restricting detachment-induced autophagic cell death to epithelial cell type I.
    Journal of Pineal Research 06/2011; 52(1):80-92. · 7.30 Impact Factor
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    ABSTRACT: The objective of the present study was to investigate the changes in a large panel of emergent geriatric biomarkers in long-term trained elderly men to analyze the effects of long-term exercise on an aged population. We collected blood samples from two groups of male volunteers older than 65 years who maintain a measure of functional independence: one group of sedentary subjects without a history of regular physical activity and the other of subjects who have sustained training, starting during adulthood (mean training time = 49 ± 8 years). We studied morbidity, polypharmacy, cellular and serological inflammatory parameters, and endocrine mediators. After adjusting for confounding factors, we observed reduced medication intake per subject and lower number of diseases per subject with statistical differences nearly significant in the long-term exercise group. We showed that long-term training was associated with lower levels of white blood cell counts, neutrophil counts, interleukin-6, interleukin-10, interleukin-1 receptor antagonist, and soluble TNF receptor-I. Furthermore, we noted an increase in the concentrations of insulin-like growth factor-1 and dehydroepiandrosterone in the long-term training group. We concluded that long-term exercise training from adulthood to old age is clearly associated with a healthy profile of emergent geriatric biomarkers. Long-term training could improve the inflammatory-endocrine imbalance associated with disease, frailty, functional decline, and mortality in elderly men. Our results point to the benefits of prolonged exercise from adulthood to old age.
    Age 06/2011; 34(3):761-71. · 6.28 Impact Factor
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    ABSTRACT: Aging is commonly defined as a physiological phenomenon associated with morphological and functional deleterious changes in which oxidative stress has a fundamental impact; therefore, readjusting the oxidative balance should have beneficial effects. In our study, we tested the antioxidant melatonin in old mouse brains and showed positive effects at the cellular and mitochondrial levels. Melatonin attenuated β-amyloid protein expression and α-synuclein deposits in the brain compared to aged group. Furthermore, oxidative stress was increased by aging and induced the nuclear translocation of nuclear factor-kappa B (NF-κB), which was suppressed by melatonin treatment. The antioxidant mitochondrial expression, superoxide dismutase 2 (SOD2), was increased in both control and melatonin-treated old mice, despite the different activation states of the NF-κB pathway. The NF-κB pathway was activated in the old mice, which may be explained by this group's response to the increased oxidative insult; this insult was inhibited in melatonin-treated animals, showing this group an increase in active mitochondria population that was not observed in old group. We also report that melatonin is capable of restoring the mitochondrial potential of age-damaged neurons. In conclusion, melatonin's beneficial effects on brain aging are linked to the increase in mitochondrial membrane potential and SOD2 expression, which probably reduces the mitochondrial contribution to the oxidative stress imbalance.
    Journal of Pineal Research 11/2010; 50(1):54-63. · 7.30 Impact Factor
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    ABSTRACT: The present study investigated the changes in several erythrocyte oxidative stress biomarkers in hypoxic elderly individuals to analyze the deleterious effects of low oxyhemoglobin saturation in an elderly population. We collected blood samples from one normoxic middle-aged group and two groups composed of individuals older than 75 years of age: one normoxic group and one hypoxic group. Aging appeared to provoke a defective erythrocyte antioxidant defense associated with increased oxidative damage in the elderly population. Acute hypoxia activated an insufficient antioxidant defense response as suggested by the oxidative damage observed. The oxidative imbalance presented in older participants and increased in hypoxia participants had a direct effect on glyceraldehyde-3-phosphate dehydrogenase cell distribution. Oxidative stress levels altered Band 3 protein and mediated caspase-3 activation in erythrocyte from the aged group although it was not extended to hypoxic individuals. Therefore, aged participants appeared to activate an insufficient antioxidant response against hypoxia-related oxidative stress.
    The Journals of Gerontology Series A Biological Sciences and Medical Sciences 11/2010; 66(4):376-84. · 4.31 Impact Factor
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    ABSTRACT: Se estudió el patrón de tenderización y la actividad de las calpaínas a lo largo de la maduración post-mortem (2 horas a 21 días) de la carne procedente de los distintos biotipos amparados por la Indicación Geográfica Protegida (IGP) “Ternera Asturiana”, según la raza (Asturiana de los Valles “AV” y Asturiana de la Montaña “AM”) y el grado de presencia del gen de la hipertrofia muscular (mh/mh, mh/+, +/+). La mutación de la miostatina en los genotipos AV (mh/mh) y (mh/+) produjo cambios significativos en la evolución post-mortem de la calidad de la carne, al promover un descenso más rápido y acusado del pH y una activación más temprana de las calpaínas y por tanto de la proteolisis del tejido muscular, mostrando un ritmo de tenderización más temprano que la carne de los genotipos normales (+/+) de ambas razas. Los resultados obtenidos indican que las diferencias encontradas entre los distintos biotipos estudiados en la acidificación post-mortem del músculo y en la actividad de las µ-calpaínas están significativamente correlacionadas con la dureza de la carne y presentan paralelismo con el proceso de tenderización.
    7º Congreso Ibérico sobre Recursos Genéticos Animales (SERGA); 09/2010
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    ABSTRACT: Oxidative stress has been reported to increase during aging and conditions of hypoxia. Although low oxygen saturation has a key role in the development of several age-related diseases, the underlying mechanisms are still unknown. We analyzed the relationship between aging and hypoxia by examining oxidative stress and inflammation-related cytokines. We collected blood samples from three volunteer experimental groups, consisting of one group of normoxic middle-aged people and two groups of individuals older than 75 years, which comprised a subgroup of normoxic subjects and another with oxyhemoglobin saturation lower than 95% (hypoxic). Our results showed a fall in antioxidant defenses in older people with hypoxia. TNF-alpha, the first element in the cytokine cascade, was significantly increased in the aged population, implying that aging is accompanied by a gradual increase in this inflammatory biomarker. IL-6 was not associated with aging, but it was highly elevated under hypoxia conditions in elderly subjects. Thus, these parameters could be used as biological markers of different inflammatory processes triggered by oxidative stress induced by a decrease in antioxidant defenses in the elderly population, with TNF-alpha as an indicator of chronic processes, such as aging, and IL-6 as a marker for acute responses, such as hypoxia.
    Free radical biology & medicine 09/2010; 49(5):733-7. · 5.42 Impact Factor
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    ABSTRACT: The subterranean blind mole rats of the superspecies Spalax ehrenbergi (Nehring, 1898) have developed several strategies to cope with changing concentrations of underground oxygen. Such an atmosphere induces the generation of reactive oxygen species that can cause oxidative damage without proper control. To understand how S. ehrenbergi appear to be able to counteract the free radicals and avoid oxidative damage, we studied the oxidative status of the Harderian gland (an organ particularly vulnerable to oxidative stress in many rodents) in two species of the superspecies S. ehrenbergi (Spalax galili and Spalax judaei) under different oxygen concentration levels, paying special attention to the antioxidant defences developed by these animals and the resulting macromolecular damage. The results presented herein reinforce the idea that S. ehrenbergi deal better with hypoxic conditions than other rodents by regulating the activity of its antioxidant enzymes. Moreover, S. galili is better adapted to hypoxic conditions, whereas S. judaei appears to be better adapted to hyperoxic conditions.Les rats-taupes aveugles et fouisseurs de la super-espèce Spalax ehrenbergi (Nehring, 1898) ont adopté plusieurs stratégies pour faire face aux changements de concentrations d'oxygène sous terre. Une telle atmosphère induit la production d'espèces réactives d'oxygène qui, sans contrôle approprié, peuvent causer des dommages oxydatifs. Afin de comprendre comment S. ehrenbergi semble être capable de contrer les radicaux libres et éviter ainsi les dommages oxydatifs, nous avons étudié le statut oxydatif de la glande de Harder (un organe particulièrement vulnérable au stress oxydatif chez plusieurs rongeurs) chez deux espèces de S. ehrenbergi (soit Spalax galili et Spalax judaei) sous diverses concentrations d'oxygène, en tenant compte particulièrement des défenses antioxydantes développées par ces animaux et du dommage macromoléculaire produit. Nos résultats appuient la proposition selon laquelle S. ehrenbergi fait mieux face aux conditions hypoxiques que les autres rongeurs en régulant l'activité de ses enzymes antioxydantes. De plus, S. galili est mieux adapté aux conditions hypoxiques, alors que S. judaei semble mieux adapté aux conditions hyperoxiques.
    Canadian Journal of Zoology 07/2010; 88(8):803-807. · 1.50 Impact Factor
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    ABSTRACT: Different biotypes of the Protected Geographical Indication (PGI) "Ternera Asturiana" were studied to determine if their differences in physicochemical characteristics and tenderization pattern during maturation (3 to 21days) had an effect on the consumer evaluation of beef palatability. Biotype affected significantly pH, water holding capacity, chemical composition (P<0.001) and meat lightness (P<0.05). Ageing time affected significantly (P<0.05) colour, meat toughness and sensory attributes in a different way within each biotype. Multivariate analysis showed two different meat groups: 1) meat from mh-genotypes, characterized by high juice losses, lightness (L*), protein content and high sensory acceptability at intermediate (7 and 14days) ageing times; 2) meat from rustic (AM) breed and biotypes free of myostatin mutation (AV (+/+) and AVxAM), showing higher intramuscular fat, myoglobin content, and instrumental toughness and requiring longer storage times (21days). This should be taken into account for the proper post-mortem management and commercialization of each product to achieve its best sensory quality.
    Meat Science 05/2010; · 2.75 Impact Factor
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    ABSTRACT: The Syrian hamster Harderian gland (HG) has a large porphyrin metabolism with a sexual dimorphism, showing male HGs much lower porphyrin concentrations than female glands. Damage derived from this production of porphyrins, displayed by reactive oxygen species, forces the gland to develop morphological changes that must have a physiological significance. Thus, oxidative stress is present in two states: mild oxidative stress in male HGs and extreme oxidative stress in female HGs. Cathepsins data gave indirect indications about the presence of programmed cell death affecting the lysosomal pathway, especially in female HGs, which showed an accumulation of autophagic bodies. Our results showed different degrees of autophagy in Syrian hamster HGs depending on sex and probably controlled by the redox-sensitive transcription factors: NFkappaB and p53. The discovery of these sexual dimorphisms in redox signaling and in autophagy corroborates previous findings and underlines the key role of reactive oxygen species in the regulation of autophagy. In addition, in this paper we propose a physiological significance for these phenomena: male HGs develop a survival autophagy, while in female HGs, autophagy culminates in a detachment-derived cell death that plays a central role in its secretory activity, leading to a massive glandular secretion.
    Autophagy 11/2009; 5(7):1004-17. · 12.04 Impact Factor
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    ABSTRACT: Aged spleens from senescence-accelerated prone mice 8 (SAMP8) and senescence-accelerated resistant mice 1 (SAMR1) were examined to determine whether sex or melatonin had an effect on oxidative stress-related immune impairments. We observed that the immunosenescence of SAMP8 mice was associated with a redox imbalance, leading to an age-related increase in oxidative damage, resulting from a decrease in antioxidant defense and protease activity. Moreover, increased apoptotic cell death, a decrease in proliferative activity and the loss of NF-kappaB activation were also related to the immunodeficiency seen in SAMP8 compared to SAMR1 mice. Females demonstrated higher oxidative stress-related alterations in the immune response, and subsequent, melatonin treatment provided the best protective effects. Pathways involved in autophagy were upregulated in SAMP8 as an adaptive response to oxidative stress, in an attempt to rescue the cell from increased apoptosis and age-related immunodeficiency. However, the NF-kappaB signaling and autophagic processes were unaffected by treatment with melatonin. Therefore, we propose a key role for NF-kappaB signaling and autophagy in the oxidative stress-related immunosenescent spleens of SAMP8 mice.
    Mechanisms of ageing and development 09/2009; 130(11-12):722-30. · 4.18 Impact Factor
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    ABSTRACT: We studied the effect of age and melatonin on cell death processes in brain aging. Senescence-accelerated prone mice 8 (SAMP8) and senescence-accelerated resistant mice (SAMR1) at 5 and 10 months of age were used as models of the study. Melatonin (10 mg/kg) or its vehicle (ethanol at 0.066%) was administered in the drinking water from 1 to 9 months of age. Neurodegeneration, previously shown in the aged brain of SAMP8 and SAMR1 at 10 months of age, may be due to a drop in age-related proteolytic activities (cathepsin D, calpains, and caspase-3). Likewise, lack of apoptotic and macroautophagic processes were found, without apparent modification by melatonin. However, the caspase-independent cell death, owing to high p53 and apoptosis-inducing factor (AIF) levels, might be an alternative pathway of cell death in the aged brain. The main effects of melatonin treatment were observed in the aged SAMR1 mice; in this strain we observed a marked increase in antioxidant activity (catalase and superoxide dismutase). Likewise, a key antioxidant role of apoptosis-related proteins, Bcl-2 and AIF, was suggested in the aged brain of SAM mice, which was clearly influenced by melatonin. Moreover, the age-related increase of lysosomal activity of cathepsin B and a lysosomal membrane-associated protein 2 supports the possibility of the maintenance of lysosomal viability in addition to age-related impairments of the proteolytic or macroautophagic activities. The effectiveness of melatonin against the oxidative stress-related impairments and apoptosis during the aging process is, once more, corroborated in this article.
    Journal of Pineal Research 02/2009; 46(1):106-14. · 7.30 Impact Factor
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    ABSTRACT: The flank organ of the Syrian hamster shows a biodynamic response to androgenic stimulation and is, therefore, a suitable model for the study of androgenic effects on hair and sebaceous glands. This organ is susceptible to programmed cell death (PCD), a prominent feature associated with sexual organ adjustment. In the present report, the type of PCD (apoptosis or autophagy) exhibited by this organ was evaluated. Caspase-3 activity, indicative of apoptosis, was not detectable in flank organ homogenates. Furthermore, cytokeratins, which are normally degraded during apoptosis, remained intact. On the other hand, Western blotting of Beclin 1 and light chain 3-II, both important autophagy markers, revealed autophagic processes in the flank organ in both sexes, especially in females. Cathepsin D activity, higher in males than in females, and procathepsin D expression were also consistent with autophagy and not apoptosis. Taken together, these data indicate that macroautophagy, and not apoptosis, is the main mechanism by which the flank organ responds to androgen. This is the first direct evidence establishing the relationship between autophagy and morphological changes in androgen-dependent organs.
    Journal of Andrology 11/2008; 30(2):113-21. · 2.53 Impact Factor
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    ABSTRACT: Senescence-accelerated mice (SAMP8) and senescence-accelerated resistant mice (SAMR1) were studied at 5 and 10 months of age, respectively. In the animals, neurodegenerative processes and how they were influenced by melatonin were examined. Melatonin (10 mg/kg) or vehicle (ethanol at 0.066%) treatments were administrated from the age of 1 to 9 months in the drinking water. Differences in the neurodegenerative markers examined were found between the two strains with a more damaged protein, phosphorylated Tau at Ser392, increased neurofibrillary tangles (NT) and higher alpha-synuclein expression in SAMP8 versus SAMR1 mice overall, when the mice were 10 months of age. Changes in density of receptors and oxidative stress-related signaling with age were found in the brains of SAM strains at 10 months as shown by a marked decrease in the level of MT-1 melatonin receptor and retinoic acid receptor-related orphan receptor (ROR)-alpha1. This diminution was earlier and more pronounced in SAMP8 mice. Likewise, the levels of nuclear factor-kappa B (NF-kB) transcriptional factor were higher in SAMP8 mice compared with SAMR1 mice regardless of age confirming the direct role of oxidative stress in the aging process. Treatment with melatonin in SAMP8 and SAMR1 mice reduced the neurodegenerative changes with an increase of ROR-alpha1 levels without an apparent influence in the levels of MT-1 receptor. However, different melatonin effects on NF-kB signaling were observed suggesting that NF-kB could trigger inflammatory processes in a different way, being SAM strain-dependent and associated with age-related oxidative stress levels. The effectiveness of melatonin in improving age-related neural impairments is corroborated.
    Journal of Pineal Research 05/2008; 45(3):302-11. · 7.30 Impact Factor
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    ABSTRACT: Double-muscled syndrome in cattle improves meat tenderness. However, the nature of the proteolytic processes associated with this phenomenon remains unknown. The aim of this study was to monitor changes in the activity of cathepsins (B, B + L, D and H) during meat aging and their gradual release from lysosomes to the cytosol in the longissimus muscle of yearling bulls of two breeds from northern Spain (Asturiana de los Valles and Asturiana de la Montaña) showing three genotypes for muscular hypertrophy (mh/mh, mh/+ and + / +). The data showed that the pattern of cathepsin activity during meat aging paralleled variations in tenderness in the different genotypes studied. Maximal cathepsin D activity and minimal cathepsin H activity were recorded during meat aging times ranging from 3 to 21 days. The activities of cathepsins B and B + L were lower than that of cathepsin D at the established time points (3, 7, 14 and 21 days post-slaughter). The role of these enzymes in the activation of cathepsin D is discussed. All cathepsins showed similar action patterns, with high levels early on in the aging process and lower levels at later times. This pattern depended on the genotype and was significantly faster (P≤0.05) in meat from mh/mh animals, intermediate in meat from mh/+ animals and slower in meat from normal (+/+) animals of both breeds. Copyright © 2006 Society of Chemical Industry
    Journal of the Science of Food and Agriculture 01/2007; 87(2):192-199. · 1.76 Impact Factor

Publication Stats

603 Citations
209.33 Total Impact Points

Institutions

  • 1989–2012
    • University of Oviedo
      • Department of Cell Biology and Morphology
      Oviedo, Asturias, Spain
  • 2011
    • University of Coimbra
      • Centro de Neurociências e Biologia Celular (CNC)
      Coimbra, Distrito de Coimbra, Portugal