1. Universidad San Pablo-CEU

Excessive dietary fat consumption has been linked to impairments in synaptic plasticity in the hippocampus (HIP), a brain region crucial for learning and memory that relies on balanced glutamatergic neurotransmission. This study investigates the acute effects of three fatty acids (FAs)—lauric acid (LA), palmitic acid (PA), and oleic acid (OA)—on glutamate (GLU)-related gene expression in the HIP of male and female young mice. Hippocampal slices were treated with FAs, and mRNA levels of genes involved in GLU transport, GLU-glutamine (GLN) cycling, and GLU receptor subunit encoding were quantified using RT-PCR. FA treatment reduced mRNA levels of enzymes involved in the conversion of GLU to GLN (glutamine synthetase; GS), GABA (glutamate decarboxylase 1; GAD67), and α-ketoglutarate (glutamate pyruvate transaminase 2; AAT2). Additionally, the expression of glutamine transporters (SNAT1, SNAT2, SNAT3), the astrocytic GLU transporter GLT-1, and the NMDA receptor subunit NMDA2a was also reduced. These effects were most pronounced with LA. Notably, while the HIP showed similar sensitivity to fatty acids across sexes, overall gene expression levels were lower in females. These findings highlight the acute susceptibility of hippocampal GLU-related pathways to FA exposure, particularly LA, suggesting potential risks of high-LA diets on cognitive function. Further research is needed to explore the long-term consequences of dietary fat on hippocampal health and its sex-specific effects.

Background There is extensive concern about older people’s care in institutions, especially recently in the past years. One of the reasons is linked to the cases of elder abuse, not only shown by academic and scientific sources, but also by social and mass media and their impact on public perception of the institutional setting. What is more, current COVID-19 pandemic consequences on older people have provoked alarm and worry especially about what is happening in institutions. Methods The sample for this study consists of 286 staff working in nursing homes in Spain. This study aimed to assess the psychometric properties of the Professional Good Care Scale in Nursing Homes (GCS-NH). Results Results of parallel analyses and exploratory factor analyses (EFAs) showed a four-factor model for the 32-item scale: humanization (9 items), non-infantilization (10 items), respect (7 items) and empowerment (6 items). Then, psychometric properties were tested analysing internal consistency (reliability) and convergent, divergent and criterion validity. High internal consistency (reliability) and different validity evidence were obtained for the total scores of the GCS-NH and its subscales. GCS-NH scores were also capable of detecting risk of probable institutional elder abuse. Conclusions Results show that this scale is an appropriate, valid, and reliable multidimensional instrument to evaluate good care in older institutionalized people by staff. Good care is an outcome of a complex construct in which a wide range of factors converge (staff, older people, and environmental characteristics). The GCS-NH has potential to be used as a multidimensional tool to assess good care.

Memory and behavioral difficulties among older people living in nursing homes can cause burden and other consequences in professional caregivers. There is a lack of instruments that evaluate these behaviors and their influence in formal caregivers. The aim of this study is to develop and psychometrically test—the Revised Memory and Behavior Problems Checklist for Nursing Homes (RMBPC-NH). A cross-sectional study was carried out. The sample was made up of 312 formal caregivers working in nursing homes from different territories in Spain, 87.5% were women and 12.5% were men. The average age of participants was 39 years (SD = 12.2). The sample was recruited from January 2019 to March 2020. Participants completed a self-administered questionnaire, which included sociodemographic information, and assessed quality of technical equipment, level of training, experience of working with older people, job satisfaction, professional quality of life, burnout, and conception of negative stereotypes held towards aging. The four-factor structure of the RMBPC-NH showed a good fit, namely in relation to memory, functional, and emotional factors, and other problems. It has shown adequate psychometric properties, internal consistency, and validity (correlations with professional quality of life, job satisfaction, burnout, and negative stereotypes). The RMBPC-NH is a useful instrument to evaluate the frequency of older people’s memory and behavior problems and professional caregivers’ burden. The practical application in nursing homes is discussed

Researchers have mainly focused on aging risk factors and COVID19 consequences. However, older adults have proved their ability to overcome adversities along their life. Resilience is a protective variable that dampens the impact of stress. Based on MacLeod’s et al. (2016) approach, we aimed to analyze the relationship between older adults’ resilience and COVID19 relatedstressors as well as their physical, mental, and social characteristics. Eight hundred eightynine people aged 60 and over participated in this study. Older participants, women, having better perceived health and not losing a loved one because of the virus were associated with more resilience. Moreover, higher levels of gratitude, personal growth, life purpose and lower levels of depression were associated with greater scores in resilience. This study ofers a change of perspective in which aging is perceived from a positive viewpoint by focusing on easily accessible resources that may help older adults to cope with adverse situations.

Objectives: Caring for older adults is a demanding task. Some professionals may find themselves in complex situations for which they may not be prepared. However, the repercussions of these difficult experiences will depend on personal factors. Resilience acts as a buffer against difficulties and experiences. However, its study with first-line caregivers in nursing homes is limited. This study aimed to validate the Connor-Davidson Resilience Scale-2 (CD-RISC2), examine its psychometric properties, and analyze the variables associated with resilience (sociodemographic and professionals´ variables). Methods: 312 nursing home professionals participated in the study. Besides the Connor-Davidson Resilience Scale-2, they answered questionnaires about good care, burnout, quality of life, person-centered care, and well-being. Results: The CD-RISC2 showed adequate reliability and test-retest reliability. Good support was found for convergent validity with perceived health, person-directed care, personal growth, life purpose, quality of life and good care, and for discriminant validity with burnout. Conclusions: To our knowledge, this is the first study that validates the CD-RISC2 Spanish version with front-line workers in nursing homes showing adequate psychometric properties. Clinical implications: An abbreviated, simpler, self-assessed version may be more useful than longer versions, especially with professionals with a heavy workload, such as direct care staff in nursing homes.

Acute leptin increase as well as endogenous hyperleptinemia evoked by high-fat diets (HF) activate fatty acid metabolism in nonadipose tissues. This supports the notion that hyperleptinemia is pivotal to prevent/delay steatosis during periods of positive energy balance. We have previously shown that long-term HF spares ectopic accumulation of lipids specifically in the miocardium. Because carnitine palmitoyltransferase I (CPT-I) allows mitochondrial uptake/oxidation of fatty acids, we have hypothesized that leptin drives cardiac CPT-I activity. In the current study, hyperleptinemia was induced in C57BL/6J mice either by exogenous leptin administration or by means of HF, and the ability of malonyl-coenzyme A (malonyl-CoA) (the main endogenous inhibitor of CPT-I) to inhibit cardiac CPT was analyzed. IC50 values of malonyl-CoA were 8.1 ± 1.5 μmol/liter in controls vs. 69.3 ± 5.2 μmol/liter (P < 0.01) in leptin-treated mice. This effect was also observed in cardiac explants incubated with leptin and was blocked by triciribine, a compound shown to inhibit proteinkinase B (Akt) phosphorylation (pAkt). In accordance, acute leptin evoked an increase of cardiac pAkt levels, which correlated with CPT sensitivity to malonyl-CoA. Otherwise, the inhibitory effect of malonyl-CoA was hindered in HF hyperleptinemic mice, and in this case, pAkt levels also correlated with CPT sensitivity to malonyl-CoA. Our data show that leptin reduces the sensitivity of cardiac CPT-I to malonyl-CoA and suggest the involvement of an Akt-related signaling pathway in this effect. This mechanism appears to be sensitive to both acute and chronic hyperleptinemia. We conclude that this action of leptin is pivotal to drive cardiac metabolism under situations associated to hyperleptinemia

Leptin is an adipocyte-derived hormone which stimulates β-oxidation in peripheral tissues and prevents steatosis. Because leptin production naturally increases during adult life, we have hypothesized that leptin receptors might undergo a physiological and gradual desensitization during ageing. Therefore we have characterized in three- five- and ten-month old mice i) the weight of different white adipose pads, heart and liver, ii) lipid content in these tissues/organs, and iii) responsiveness to acute leptin, measured in terms of phosphorylation of signal transducer and activator of transcription 3 (STAT3) and protein kinase B (Akt). In this study we have detected that leptin-mediated STAT3 phosphorylation appears to be preserved in cardiac tissue even in 10-month old animals but not in adipose tissue and liver of five- and ten-month old mice, respectively. Nevertheless, leptin increased pAkt content in the liver of these mice. In a parallel study we have analyzed the functionality of leptin signalling pathways in 10-month old obese mice and we have observed that the STAT3 pathway appears to be only operative in the heart whereas the Akt pathway remains functional both in heart and liver. Nevertheless, hepatic lipids increased almost 300% compared to age-matched lean controls. Our data demonstrate that during adult life there is a lost of leptin receptor functionality which is tissue-dependent and mainly affects the STAT3 pathway. Otherwise we demonstrate that the antisteatotic effect of leptin is independent of the Akt signalling pathway.

It has been suggested that hyperglycemia and insulin resistance triggered by energy-dense diets can account for hippocampal damage and deficits of cognitive behaviour. We wonder if the impairment of learning and memory processes detected in diet-induced obese (DIO) mice is linked to diet composition itself. With this purpose we have evaluated learning performance in mice undergoing a short-term highfat (HF) treatment, which leads to a pre-obese state characterized by increased adiposity without significant changes of glucose and insulin plasma levels. C57BL/6J mice were fed either a HF (45 kcal% from fat) or control diet (10 kcal% from fat) during 8 weeks. Learning performance was evaluated by using the fourarm baited version of the eight-arm radial maze test (RAM). Mice were trained to learn the RAM protocol and then memory was tested at different time-points. Time spent to consume food placed in baited arms and errors committed to find them were measured in all sessions. DIO mice significantly spent more time in learning the task and made a greater number of errors than controls. Moreover, retention tests revealed that both working and total memory errors were also more numerous in DIO mice. The current results show that short-term DIO impairs spatial learning and suggest that impairment of hippocampal learning elicited by HF diets might be perceptible before metabolic alterations linked to obesity develop

Recent studies provide evidence that high-fat diets (HF) trigger both i) a deficit of reward responses linked to a decrease of mesolimbic dopaminergic activity, and ii) a disorganization of circadian feeding behavior that switch from a structured meal-based schedule to a continuous snacking, even during periods normally devoted to rest. This feeding pattern has been shown to be a cause of HF-induced overweight and obesity. Our hypothesis deals with the eventual link between the rewarding properties of food and the circadian distribution of meals. We have investigated the effect of circadian feeding pattern on reward circuits by means of the conditioned-place preference (CPP) paradigm and we have characterized the rewarding properties of natural (food) and artificial (cocaine) reinforcers both in free-feeding ad libitum HF mice and in HF animals submitted to a re-organized feeding schedule based on the standard feeding behavior displayed by mice feeding normal chow (“forced synchronization”). We demonstrate that i) ad libitum HF diet attenuates cocaine and food reward in the CPP protocol, and ii) forced synchronization of feeding prevents this reward deficit. Our study provides further evidence that the rewarding impact of food with low palatability is diminished in mice exposed to a high-fat diet and strongly suggest that the decreased sensitivity to chow as a positive reinforcer triggers a disorganized feeding pattern which might account for metabolic disorders leading to obesity.