Impact effects of COVID-19 pandemic on chronic disease patients: A longitudinal prospective study.

AIMS: To assess the effects of COVID-19 pandemic on clinical variables as part of the routine clinical monitoring of patients with chronic diseases in primary care. DESIGN: A prospective longitudinal study was conducted in primary care centres of the Andalusian Health Service. METHODS: Data were recorded before the pandemic (T1), during the declaration of the state of emergency (T2) and in the transition phase (T3). The Barthel index and the Short Portable Mental Status Questionnaire (SPMSQ) were used to analyse functional and cognitive changes at the three time points. HbA1c, systolic and diastolic blood pressure, heart rate, BMI and lipid levels were assessed as clinical variables. Descriptive statistics and non-parametric chi-square test were used for analysis. STROBE checklist was used for the preparation of this paper. RESULTS: A total fo148 patients with chronic conditions were included in the analysis. Data analysis revealed in T2 only significant reductions in BMI, total levels of cholesterol and HDL during the onset of the pandemic. Barthel Index, SPMSQ, blood pressure and triglycerides and LDL levels worsened in T2, and the negative effects were maintained in T3. Compared to pre-pandemic values, HbA1c levels improved in T3, but HDL levels worsened. CONCLUSIONS: COVID-19 has drastically disrupted several functional, cognitive and biological variables. These results may be useful in identifying clinical parameters that deserve closer attention in the case of a new health crisis. Further studies are needed to assess the potential impacts of each specific chronic condition. IMPACT: Cognitive and functional status, blood pressure and triglycerides and LDL levels worsen in short term, maintaining the negative effects in medium-term.

Correlational Study of Aminopeptidase Activities between Left or Right Frontal Cortex versus the Hypothalamus, Pituitary, Adrenal Axis of Spontaneously Hypertensive Rats Treated with Hypotensive or Hypertensive Agents.

It has been suggested that the neuro-visceral integration works asymmetrically and that this asymmetry is dynamic and modifiable by physio-pathological influences. Aminopeptidases of the renin-angiotensin system (angiotensinases) have been shown to be modifiable under such conditions. This article analyzes the interactions of these angiotensinases between the left or right frontal cortex (FC) and the same enzymes in the hypothalamus (HT), pituitary (PT), adrenal (AD) axis (HPA) in control spontaneously hypertensive rats (SHR), in SHR treated with a hypotensive agent in the form of captopril (an angiotensin-converting enzyme inhibitor), and in SHR treated with a hypertensive agent in the form of the L-Arginine hypertensive analogue L-NG-Nitroarginine Methyl Ester (L-NAME). In the control SHR, there were significant negative correlations between the right FC with HPA and positive correlations between the left FC and HPA. In the captopril group, the predominance of negative correlations between the right FC and HPA and positive correlations between the HPA and left FC was maintained. In the L-NAME group, a radical change in all types of interactions was observed; particularly, there was an inversion in the predominance of negative correlations between the HPA and left FC. These results indicated a better balance of neuro-visceral interactions after captopril treatment and an increase in these interactions in the hypertensive animals, especially in those treated with L-NAME.

The Thing (1982): un primer modelo de prediagnóstico para las infecciones y alteraciones de la fisiología / The Thing (1982): A First Prediagnostic Model for Infections and Alterations of Physiology

The Thing / La cosa (El enigma de otro mundo) (1982) de John Carpenter, supone un reto audiovisual para pensar en el descubrimiento de claves para la detección temprana de infecciones hostiles. La búsqueda de técnicas rápidas y sencillas para la resolución de casos supone la diferencia entre la supervivencia y mantenerse en la desconfianza para un grupo que trata de descubrir quienes de ellos están infectados, y no terminar transformados en «otra cosa». Este trabajo permitirá al estudiantado conocer los cambios en el equilibrio homeostático que supondría la relación con los microorganismos de distinta naturaleza presentes en la sangre. (AU)

The Thing (1982) by John Carpenter represents an audiovisual challenge to think about the discovery of keys for the early detection of hostile infections. The search for quick and easy techniques for solving cases means the difference between survival and remaining suspicious for a group that tries to discover which of them are infected, and not end up transformed into «something else». This work will allow the student body to know the changes in the homeostatic balance that the relationship with microorganisms of different nature present in the blood would imply. (AU)

Systematic Review and Meta-Analyses of Aminopeptidases as Prognostic Biomarkers in Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons in the spinal cord, brain stem, and cerebral cortex. Biomarkers for ALS are essential for disease detection and to provide information on potential therapeutic targets. Aminopeptidases catalyze the cleavage of amino acids from the amino terminus of protein or substrates such as neuropeptides. Since certain aminopeptidases are known to increase the risk of neurodegeneration, such mechanisms may reveal new targets to determine their association with ALS risk and their interest as a diagnostic biomarker. The authors performed a systematic review and meta-analyses of genome-wide association studies (GWASs) to identify reported aminopeptidases genetic loci associated with the risk of ALS. PubMed, Scopus, CINAHL, ISI Web of Science, ProQuest, LILACS, and Cochrane databases were searched to retrieve eligible studies in English or Spanish, published up to 27 January 2023. A total of 16 studies were included in this systematic review, where a series of aminopeptidases could be related to ALS and could be promising biomarkers (DPP1, DPP2, DPP4, LeuAP, pGluAP, and PSA/NPEPPS). The literature reported the association of single-nucleotide polymorphisms (SNPs: rs10260404 and rs17174381) with the risk of ALS. The genetic variation rs10260404 in the DPP6 gene was identified to be highly associated with ALS susceptibility, but meta-analyses of genotypes in five studies in a matched cohort of different ancestry (1873 cases and 1861 control subjects) showed no ALS risk association. Meta-analyses of eight studies for minor allele frequency (MAF) also found no ALS association for the "C" allele. The systematic review identified aminopeptidases as possible biomarkers. However, the meta-analyses for rs1060404 of DPP6 do not show a risk associated with ALS.

Aminopeptidase Activities Interact Asymmetrically between Brain, Plasma and Systolic Blood Pressure in Hypertensive Rats Unilaterally Depleted of Dopamine.

Brain dopamine, in relation to the limbic system, is involved in cognition and emotion. These functions are asymmetrically processed. Hypertension not only alters such functions but also their asymmetric brain pattern as well as their bilateral pattern of neurovisceral integration. The central and peripheral renin-angiotensin systems, particularly the aminopeptidases involved in its enzymatic cascade, play an important role in blood pressure control. In the present study, we report how these aminopeptidases from left and right cortico-limbic locations, plasma and systolic blood pressure interact among them in spontaneously hypertensive rats (SHR) unilaterally depleted of dopamine. The study comprises left and right sham and left and right lesioned (dopamine-depleted) rats as research groups. Results revealed important differences in the bilateral behavior comparing sham left versus sham right, lesioned left versus lesioned right, and sham versus lesioned animals. Results also suggest an important role for the asymmetrical functioning of the amygdala in cardiovascular control and an asymmetrical behavior in the interaction between the medial prefrontal cortex, hippocampus and amygdala with plasma, depending on the left or right depletion of dopamine. Compared with previous results of a similar study in Wistar-Kyoto (WKY) normotensive rats, the asymmetrical behaviors differ significantly between both WKY and SHR strains.

Proyecto lázaro (2016): de la criopreservación celular a humana. Mito y realidad para la formación docente en el área de ciencias de la salud / Realive (2016): from cellular to human cryopreservation. Myth and reality for teacher training in the area of health sciences

Existe un creciente pensamiento de postergar el avance de una enfermedad terminal mediante la criopreservación de los cuerpos de los pacientes. Ante el miedo a morir de enfermedades se confían que en el futuro podrán ser reanimados y tratados con novedosas terapias que le supondrán la cura y eliminación de la patología. Aunque parezca ciencia ficción la realidad es que ya se está realizando con organismos celulares para la conservación de especies y ante enfermedades que alteran la reproducción. Sin embargo, cuando se trata de embriones los comités éticos no tienen todavía una estrategia definida. Por esa razón, este trabajo intenta enfocar una interrelación entre profesorado y alumnado para la discusión y reflexión de la criopreservación de pacientes, mostrando los últimos avances e informes sobre este aspecto. (AU)

There is a growing thought of delaying the progression of a terminal illness by cryopreservation of the bodies of patients. Faced with the fear of dying from diseases, they are confident that in the future they will be able to be revived and treated with novel therapies that will lead to the cure and elimination of the pathology. Although it seems science fiction, the reality is that it is already being carried out with cellular organisms for the conservation of species and against diseases that alter reproduction. However, when it comes to embryos, the ethical committees do not yet have a defined strategy. For this reason, this work tries to focus on an interrelation between teachers and students for the discussion and reflection of the cryopreservation of patients, showing the latest advances and reports on this aspect. (AU)

Asymmetric Interaction of Neuropeptidase Activities between Cortico-Limbic Structures, Plasma and Cardiovascular Function after Unilateral Dopamine Depletions of the Nigrostriatal System.

In emotional processing, dopamine (DA) plays an essential role, and its deterioration involves important consequences. Under physiological conditions, dopamine exhibits brain asymmetry and coexists with various neuropeptides that can coordinate the processing of brain functions. Brain asymmetry can extend into a broader concept of asymmetric neurovisceral integration, including behavior. The study of the activity of neuropeptide regulatory enzymes (neuropeptidases, NPs) is illustrative. We have observed that the left and right brain areas interact intra- and inter-hemispherically, as well as with peripheral tissues or with physiological parameters such as blood pressure or with behaviors such as turning preference. To obtain data that reflect this integrative behavior, we simultaneously analyzed the impact of left or right brain DA depletion on the activity of various NPs in corticolimbic regions of the left and right hemispheres, such as the medial prefrontal cortex, amygdala and hippocampus, as well as on the plasma activity of the same aminopeptidase activities (APs) and on systolic blood pressure (SBP). Intra- and inter-hemispheric interactions as well as the interactions of NPs from the left or right hemispheres were analyzed with the same plasma APs and the SBP obtained from sham and from left or right lesioned rats. The results demonstrate a complex profile depending on the hemisphere considered. They definitively confirm an asymmetric neurovisceral integration and reveal a higher level of inter-hemispheric corticolimbic interactions including with SBP after left dopamine depletion.

Effect of a game-based intervention on preoperative pain and anxiety in children: A systematic review and meta-analysis.

BACKGROUND: Games are increasingly being used as a means of alleviating pain and anxiety in paediatric patients, in the view that this form of distraction is effective, non-invasive and non-pharmacological. AIMS: To determine whether a game-based intervention (via gamification or virtual reality) during the induction of anaesthesia reduces preoperative pain and anxiety in paediatric patients. METHODS: A systematic review with meta-analysis of randomised controlled trials was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and using RevMan software. The review was based on a search of the EMBASE, CINAHL, Medline, SciELO and Scopus databases, conducted in July 2021. No restriction was placed on the year of publication. RESULTS: 26 studies were found, with a total study population of 2525 children. Regarding pain reduction, no significant differences were reported. For anxiety during anaesthesia induction, however, a mean difference of -10.62 (95% CI -13.85, -7.39) on the Modified Yale Preoperative Anxiety Scale, in favour of game-based intervention, was recorded. CONCLUSIONS: Game-based interventions alleviate preoperative anxiety during the induction of anaesthesia in children. This innovative and pleasurable approach can be helpful in the care of paediatric surgical patients. RELEVANCE TO CLINICAL PRACTICE: In children, preoperative management is a challenging task for healthcare professionals, and game-based strategies could enhance results, improving patients' emotional health and boosting post-surgery recovery. Distractive games-based procedures should be considered for incorporation in the pre-surgery clinical workflow in order to optimise healthcare.

The Type of Fat in the Diet Influences Regulatory Aminopeptidases of the Renin-Angiotensin System and Stress in the Hypothalamic-Pituitary-Adrenal Axis in Adult Wistar Rats.

(1) Background: Prolonged feeding with a high-fat diet (HFD) acts as a stressor by activating the functions of the hypothalamic-pituitary-adrenal gland (HPA) stress axis, accompanied of hypertension by inducing the renin-angiotensin-aldosterone system. Angiotensinases enzymes are regulatory aminopeptidases of angiotensin metabolism, which together with the dipeptidyl peptidase IV (DPP-IV), pyroglutamyl- and tyrosyl-aminopeptidase (pGluAP, TyrAP), participate in cognitive, stress, metabolic and cardiovascular functions. These functions appear to be modulated by the type of fat used in the diet. (2) Methods: To analyze a possible coordinated response of aminopeptidases, their activities were simultaneously determined in the hypothalamus, adenohypophysis and adrenal gland of adult male rats fed diets enriched with monounsaturated (standard diet (S diet) supplemented with 20% virgin olive oil; VOO diet) or saturated fatty acids (diet S supplemented with 20% butter and 0.1% cholesterol; Bch diet). Aminopeptidase activities were measured by fluorimetry using 2-Naphthylamine as substrates. (3) Results: the hypothalamus did not show differences in any of the experimental diets. In the pituitary, the Bch diet stimulated the renin-angiotensin system (RAS) by increasing certain angiotensinase activities (alanyl-, arginyl- and cystinyl-aminopeptidase) with respect to the S and VOO diets. DPP-IV activity was increased with the Bch diet, and TyrAP activity decrease with the VOO diet, having both a crucial role on stress and eating behavior. In the adrenal gland, both HFDs showed an increase in angiotensinase aspartyl-aminopeptidase. The interrelation of angiotensinases activities in the tissues were depending on the type of diet. In addition, correlations were shown between angiotensinases and aminopeptidases that regulate stress and eating behavior. (4) Conclusions: Taken together, these results support that the source of fat in the diet affects several peptidases activities in the HPA axis, which could be related to alterations in RAS, stress and feeding behavior.

High-Fat Diets Modify the Proteolytic Activities of Dipeptidyl-Peptidase IV and the Regulatory Enzymes of the Renin-Angiotensin System in Cardiovascular Tissues of Adult Wistar Rats.

(1) Background: The replacement of diets high in saturated fat (SAFA) with monounsaturated fatty acids (MUFA) is associated with better cardiovascular function and is related to the modulation of the activity of the local renin-angiotensin system (RAS) and the collagenase activity of dipeptidyl peptidase IV (DPP-IV). The objective of the work was to verify the capacity of different types of dietary fat on the regulatory activities of RAS and DPP-IV. (2) Methods: Male Wistar rats were fed for 24 weeks with three different diets: the standard diet (S), the standard diet supplemented with virgin olive oil (20%) (VOO), or with butter (20%) plus cholesterol (0.1%) (Bch). The proteolytic activities were determined by fluorometric methods in the soluble (sol) and membrane-bound (mb) fractions of the left ventricle and atrium, aorta, and plasma samples. (3) Results: With the VOO diet, angiotensinase values were significantly lower than with the Bch diet in the aorta (GluAP and ArgAP (mb)), ventricle (ArgAP (mb)) and atrium (CysAP (sol)). Significant decreases in DPP-IV (mb) activity occurred with the Bch diet in the atrium and aorta. The VOO diet significantly reduced the activity of the cardiac damage marker LeuAP (mb) in the ventricle and aorta, except for LeuAP (sol) in the ventricle, which was reduced with the Bch diet. (4) Conclusions: The introduction into the diet of a source rich in MUFA would have a beneficial cardiovascular effect on RAS homeostasis and cardiovascular functional stability.

Interaction between Angiotensinase Activities in Pituitary and Adrenal Glands of Wistar-Kyoto and Spontaneously Hypertensive Rats under Hypotensive or Hypertensive Treatments.

In the present study, we analyzed the activity of several aminopeptidases (angiotensinases) involved in the metabolism of various angiotensin peptides, in pituitary and adrenal glands of untreated Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) or treated with the antihypertensive drugs captopril and propranolol or with the L-Arginine hypertensive analogue L-NG-Nitroarginine Methyl Ester (L-NAME). Intra- and inter-gland correlations between angiotensinase activities were also calculated. Membrane-bound alanyl-, cystinyl-, and glutamyl-aminopeptidase activities were determined fluorometrically using aminoacyl-ß-naphthylamide as substrates. Depending on the type of angiotensinase analyzed, the results reflect a complex picture showing substantial differences between glands, strains, and treatments. Alanyl-aminopeptidase responsible for the metabolism of Ang III to Ang IV appears to be the most active angiotensinase in both pituitary and adrenals of WKY and particularly in SHR. Independently of treatment, most positive correlations are observed in the pituitary gland of WKY whereas such positive correlations are predominant in adrenals of SHR. Negative inter-gland correlations were observed in control SHR and L-NAME treated WKY. Positive inter-gland correlations were observed in captopril-treated SHR and propranolol-treated WKY. These results may reflect additional mechanisms for increasing or decreasing systolic blood pressure in WKY or SHR.

Effects of Virgin Olive Oil on Blood Pressure and Renal Aminopeptidase Activities in Male Wistar Rats.

High saturated fat diets have been associated with the development of obesity and hypertension, along with other pathologies related to the metabolic syndrome. In contrast, the Mediterranean diet, characterized by its high content of monounsaturated fatty acids, has been proposed as a dietary factor capable of positively regulating cardiovascular function. These effects have been linked to changes in the local renal renin angiotensin system (RAS) and the activity of the sympathetic nervous system. The main goal of this study was to analyze the role of two dietary fat sources on aminopeptidases activities involved in local kidney RAS. Male Wistar rats (six months old) were fed during 24 weeks with three different diets: the standard diet (S), the standard diet supplemented with virgin olive oil (20%) (VOO), or the standard diet enriched with butter (20%) plus cholesterol (0.1%) (Bch). Kidney samples were separated in medulla and cortex for aminopeptidase activities (AP) assay. Urine samples were collected for routine analysis by chemical tests. Aminopeptidase activities were determined by fluorometric methods in soluble (sol) and membrane-bound (mb) fractions of renal tissue, using arylamide derivatives as substrates. After the experimental period, the systolic blood pressure (SBP) values were similar in standard and VOO animals, and significantly lower than in the Bch group. At the same time, a significant increase in GluAP and IRAP activities were found in renal medulla of Bch animals. However, in VOO group the increase of GluAP activity in renal medulla was lower, while AspAP activity decreased in the renal cortex. Furthermore, the VOO diet also affected other aminopeptidase activities, such as TyrAP and pGluAP, related to the regulation of the sympathetic nervous system and the metabolic rate. These results support the beneficial effect of VOO in the regulation of SBP through changes in local AP activities of the kidney.

Hypothalamic Renin-Angiotensin System and Lipid Metabolism: Effects of Virgin Olive Oil versus Butter in the Diet.

The brain renin-angiotensin system (RAS) has been recently involved in the homeostatic regulation of energy. Our goal was to analyse the influence of a diet rich in saturated fatty acids (butter) against one enriched in monounsaturated fatty acids (olive oil) on hypothalamic RAS, and their relationship with the metabolism of fatty acids. Increases in body weight and visceral fat, together with an increase in aminopeptidase A expression and reductions in AngII and AngIV were observed in the hypothalamus of animals fed with the butter diet. In this group, a marked reduction in the expression of genes related to lipid metabolism (LPL, CD36, and CPT-1) was observed in liver and muscle. No changes were found in terms of body weight, total visceral fat and the expression of hepatic genes related to fatty acid metabolism in the olive oil diet. The expressions of LPL and CD36 were reduced in the muscles, although the decrease was lower than in the butter diet. At the same time, the fasting levels of leptin were reduced, no changes were observed in the hypothalamic expression of aminopeptidase A and decreases were noted in the levels of AngII, AngIV and AngIII. These results support that the type of dietary fat is able to modify the hypothalamic profile of RAS and the body energy balance, related to changes in lipid metabolism.

Bombarderos en picado (1941): un modelo de estudio de la fisiología de la aviación / Dive Bomber (1941): a study model of aviation physiology

Este artículo sirve para iniciarse en las bases docentes de la actual fisiología de la aviación, cuyo origen se remonta al comienzo de la Segunda Guerra Mundial. Bombarderos en picado (1941) de Michael Curtiz es un excelente material docente para ayudar en la comprensión de las distintas causas del síncope de los pilotos en las alturas, permitiendo la reflexión y la búsqueda de soluciones o alternativas a través de experimentos que permiten la recuperación de la homeostasis corporal. Su material audiovisual comparte escenas reales del ejército americano que permiten acceder a estos descubrimientos y al avance del estado actual de la moderna fisiología aeroespacial

This article serves to begin in the teaching bases of the current aviation physiology, whose origin dates back to the beginning of World War II. Dive Bomber (1941) by Michael Curtiz is an excellent teaching material to help in the understanding of the different causes of the pilots’ syncope at heights, allowing thinking and the search for solutions or alternatives through experiments that allow the recovery of the body homeostasis. His audiovisual material shares real scenes of the United States Army that allow access to these discoveries and the progress of the current state of modern aerospace physiology

The Role of High Fat Diets and Liver Peptidase Activity in the Development of Obesity and Insulin Resistance in Wistar Rats.

High-fat diets (HFD) have been widely associated with an increased risk of metabolic disorders and overweight. However, a high intake of sources that are rich in monounsaturated fatty acids has been suggested as a dietary agent that is able to positively influence energy metabolism and vascular function. The main objective of this study was to analyze the role of dietary fats on hepatic peptidases activities and metabolic disorders. Three diets: standard (S), HFD supplemented with virgin olive oil (VOO), and HFD supplemented with butter plus cholesterol (Bch), were administered over six months to male Wistar rats. Plasma and liver samples were collected for clinical biochemistry and aminopeptidase activities (AP) analysis. The expression of inducible nitric oxide synthase (iNOS) was also determined by Western blot in liver samples. The diet supplement with VOO did not induce obesity, in contrast to the Bch group. Though the VOO diet increased the time that was needed to return to the basal levels of plasma glucose, the fasting insulin/glucose ratio and HOMA2-%B index (a homeostasis model index of insulin secretion and valuation of ß-cell usefulness (% ß-cell secretion)) were improved. An increase of hepatic membrane-bound dipeptidyl-peptidase 4 (DPP4) activity was found only in VOO rats, even if no differences in fasting plasma glucagon-like peptide 1 (GLP-1) were obtained. Both HFDs induced changes in hepatic pyroglutamyl-AP in the soluble fraction, but only the Bch diet increased the soluble tyrosyl-AP. Angiotensinase activities that are implicated in the metabolism of angiotensin II (AngII) to AngIV increased in the VOO diet, which was in agreement with the higher activity of insulin-regulated-AP (IRAP) in this group. Otherwise, the diet that was enriched with butter increased soluble gamma-glutamyl transferase (GGT) and Leucyl-AP, iNOS expression in the liver, and plasma NO. In summary, VOO increased the hepatic activity of AP that were related to glucose metabolism (DPP4, angiotensinases, and IRAP). However, the Bch diet increased activities that are implicated in the control of food intake (Tyrosine-AP), the index of hepatic damage (Leucine-AP and GGT), and the expression of hepatic iNOS and plasma NO. Taken together, these results support that the source of fat in the diet affects several peptidases activities in the liver, which could be related to alterations in feeding behavior and glucose metabolism.

Sp1-regulated expression of p11 contributes to motor neuron degeneration by membrane insertion of TASK1.

Disruption in membrane excitability contributes to malfunction and differential vulnerability of specific neuronal subpopulations in a number of neurological diseases. The adaptor protein p11, and background potassium channel TASK1, have overlapping distributions in the CNS. Here, we report that the transcription factor Sp1 controls p11 expression, which impacts on excitability by hampering functional expression of TASK1. In the SOD1-G93A mouse model of ALS, Sp1-p11-TASK1 dysregulation contributes to increased excitability and vulnerability of motor neurons. Interference with either Sp1 or p11 is neuroprotective, delaying neuron loss and prolonging lifespan in this model. Nitrosative stress, a potential factor in human neurodegeneration, stimulated Sp1 expression and human p11 promoter activity, at least in part, through a Sp1-binding site. Disruption of Sp1 or p11 also has neuroprotective effects in a traumatic model of motor neuron degeneration. Together our work suggests the Sp1-p11-TASK1 pathway is a potential target for treatment of degeneration of motor neurons.

Light-dark influence on enkephalinase activity in hypothalamus and pituitary.

OBJECTIVES: Enkephalins functions are partly modulated by enkephalinases especially membrane-bound alanyl aminopeptidase (EC-3.4.11.2) considered as the major enkephalin-degrading enzyme in brain. The analysis of its activity in standard and non-standard light/dark conditions may help the understanding of the regulatory mechanisms of enkephalins. METHODS: Enkephalinase activity was determined fluorometrically, using an arylamide derivative as substrate, in hypothalamus and pituitary of adult male rats, in a standard 12:12 h light/dark cycle; samples were collected at 10:00 h, 13:00 h and 16:00 h of the light period (light on from 7:00 to 19:00 h) and at 22:00 h, 01:00 h and 04:00 h of the dark one (light off from 19:00 h to 07:00 h). For comparison, the enzymatic activity was also measured in the same locations at the same time-points but under constant light conditions. RESULTS: In standard light/dark conditions, the results demonstrated an opposite daily rhythm in hypothalamus and pituitary. While the highest levels of AlaAP or enkephalinase activities were measured in hypothalamus during the dark period, they were the highest in the pituitary during the light one. In contrast, the lowest levels of activity were observed in the light period in the hypothalamus whereas they were in the dark one in the pituitary. A similar pattern was observed under constant light. The differences were however higher in hypothalamus and lower, but still significant, in pituitary. CONCLUSION: These results may reflect the behaviour of the endogenous substrates of enkephalinase and consequently be involved in their functions. This observation may affect the chronotherapeutic strategies.

Diurnal opposite variation between angiotensinase activities in photo-neuro-endocrine tissues of rats.

Central and peripheral renin-angiotensin systems (RASs) act in a coordinated manner for the physiologic functions regulated by neuroendocrine events. However, whereas the diurnal rhythm of peripheral circulatory and tissue RASs is well known, the circadian behaviour of their components in central photo-neuro-endocrine structures, key elements for the control of circadian rhythms, has been barely studied. In the present study, we analysed the aspartyl- (AspAP) and glutamyl-aminopeptidase (GluAP) (aminopeptidase A) activities, the angiotensinases responsible for the metabolism of Ang I to Ang 2-10 and Ang II to Ang III, respectively, in the retina, anterior hypothalamus and pituitary at different light and dark time-points of a 12:12 h light:dark cycle (7-19 h light), using arylamide derivatives as substrates. The results demonstrated that while retina and pituitary exhibited their highest levels of AspAP activity in the light period and the lowest in the dark one, the contrary occurred in the hypothalamus - the lowest levels were observed in light conditions and the highest in darkness. The outcome for GluAP showed the highest levels in the light period and the lowest in the dark one in the three tissues analysed. In conclusion, changes in angiotensinase activities throughout the daytime may cause changes of their respective substrates and derived peptides and, consequently, in their functions. This observation may have implications for the treatment of hypertension.

Influence of a Virgin Olive Oil versus Butter Plus Cholesterol-Enriched Diet on Testicular Enzymatic Activities in Adult Male Rats.

The aim of the present work was to improve our knowledge on the mechanisms underlying the beneficial or deleterious effects on testicular function of the so-called Mediterranean and Western diet by analyzing glutamyl aminopeptidase (GluAP), gamma glutamyl transpeptidase (GGT) and dipeptidyl peptidase IV (DPP IV) activities in testis, as enzymes involved in testicular function. Male Wistar rats (6 months old) were fed for 24 weeks with three different diets: standard (S), an S diet supplemented with virgin-olive-oil (20%) (VOO), or a S diet enriched with butter (20%) plus cholesterol (0.1%) (Bch). At the end of the experimental period, plasma lipid profiled (total triglycerides, total cholesterol and cholesterol fractions (HDL, LDL and VDL)) were measured. Enzymatic activities were determined by fluorimetric methods in soluble (sol) and membrane-bound (mb) fractions of testicular tissue using arylamide derivatives as substrates. Results indicated an increase in plasmatic triglycerides, total cholesterol, LDL and VLDL in Bch. A significant increase of mb GluAP and GGT activities was also found in this diet in comparison with the other two diets. Furthermore, significant and positive correlations were established between these activities and plasma triglycerides and/or total cholesterol. These results support a role for testicular GluAP and GGT activities in the effects of saturated fat (Western diet) on testicular functions. In contrast, VOO increased sol DPP IV activity in comparison with the other two diets, which support a role for this activity in the effects of monounsaturated fat (Mediterranean diet) on testicular function. The present results strongly support the influence of fatty acids and cholesterol on testicular GluAP and GGT activities and also provide support that the reported beneficial influence of the Mediterranean diet in male fertility may be mediated in part by an increase of testicular sol DPP IV activity.