Downregulation of PLIN2 in human dermal fibroblasts impairs mitochondrial function in an age-dependent fashion and induces cell senescence via GDF15

Perilipin 2 (PLIN2) is a lipid droplet (LD)-coating protein playing important roles in lipid homeostasis and suppression of lipotoxicity in different tissues and cell types. Recently, a role for PLIN2 in supporting mitochondrial function has emerged. PLIN2 dysregulation is involved in many metabolic disorders and age-related diseases. However, the exact consequences of PLIN2 dysregulation are not yet completely understood. In this study, we knocked down (KD) PLIN2 in primary human dermal fibroblasts (hDFs) from young (mean age 29 years) and old (mean age 71 years) healthy donors. We have found that PLIN2 KD caused a decline of mitochondrial function only in hDFs from young donors, while mitochondria of hDFs from old donors (that are already partially impaired) did not significantly worsen upon PLIN2 KD. This mitochondrial impairment is associated with the increased expression of the stress-related mitokine growth differentiation factor 15 (GDF15) and the induction of cell senescence. Interestingly, the simultaneous KD of PLIN2 and GDF15 abrogated the induction of cell senescence, suggesting that the increase in GDF15 is the mediator of this phenomenon. Moreover, GDF15 KD caused a profound alteration of gene expression, as observed by RNA-Seq analysis. After a more stringent analysis, this alteration remained statistically significant only in hDFs from young subjects, further supporting the idea that cells from old and young donors react differently when undergoing manipulation of either PLIN2 or GDF15 genes, with the latter being likely a downstream mediator of the former.

Physical performance strongly predicts all-cause mortality risk in a real-world population of older diabetic patients: machine learning approach for mortality risk stratification

Background

Prognostic risk stratification in older adults with type 2 diabetes (T2D) is important for guiding decisions concerning advance care planning.

Materials and methods

A retrospective longitudinal study was conducted in a real-world sample of older diabetic patients afferent to the outpatient facilities of the Diabetology Unit of the IRCCS INRCA Hospital of Ancona (Italy). A total of 1,001 T2D patients aged more than 70 years were consecutively evaluated by a multidimensional geriatric assessment, including physical performance evaluated using the Short Physical Performance Battery (SPPB). The mortality was assessed during a 5-year follow-up. We used the automatic machine-learning (AutoML) JADBio platform to identify parsimonious mathematical models for risk stratification.

Results

Of 977 subjects included in the T2D cohort, the mean age was 76.5 (SD: 4.5) years and 454 (46.5%) were men. The mean follow-up time was 53.3 (SD:15.8) months, and 209 (21.4%) patients died by the end of the follow-up. The JADBio AutoML final model included age, sex, SPPB, chronic kidney disease, myocardial ischemia, peripheral artery disease, neuropathy, and myocardial infarction. The bootstrap-corrected concordance index (c-index) for the final model was 0.726 (95% CI: 0.687-0.763) with SPPB ranked as the most important predictor. Based on the penalized Cox regression model, the risk of death per unit of time for a subject with an SPPB score lower than five points was 3.35 times that for a subject with a score higher than eight points (P-value <0.001).

Conclusion

Assessment of physical performance needs to be implemented in clinical practice for risk stratification of T2D older patients.

Demonstrating Agreement between Radio and Fluorescence Measurements of the Depth of Maximum of Extensive Air Showers at the Pierre Auger Observatory

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

Biomarkers of aging in frailty and age-associated disorders: State of the art and future perspective

According to the Geroscience concept that organismal aging and age-associated diseases share the same basic molecular mechanisms, the identification of biomarkers of age that can efficiently classify people as biologically older (or younger) than their chronological (i.e. calendar) age is becoming of paramount importance. These people will be in fact at higher (or lower) risk for many different age-associated diseases, including cardiovascular diseases, neurodegeneration, cancer, etc. In turn, patients suffering from these diseases are biologically older than healthy age-matched individuals. Many biomarkers that correlate with age have been described so far. The aim of the present review is to discuss the usefulness of some of these biomarkers (especially soluble, circulating ones) in order to identify frail patients, possibly before the appearance of clinical symptoms, as well as patients at risk for age-associated diseases. An overview of selected biomarkers will be discussed in this regard, in particular we will focus on biomarkers related to metabolic stress response, inflammation, and cell death (in particular in neurodegeneration), all phenomena connected to inflammaging (chronic, low-grade, age-associated inflammation). In the second part of the review, next-generation markers such as extracellular vesicles and their cargos, epigenetic markers and gut microbiota composition, will be discussed. Since recent progresses in omics techniques have allowed an exponential increase in the production of laboratory data also in the field of biomarkers of age, making it difficult to extract biological meaning from the huge mass of available data, Artificial Intelligence (AI) approaches will be discussed as an increasingly important strategy for extracting knowledge from raw data and providing practitioners with actionable information to treat patients.

Apoptotic volume decrease (AVD) in A549 cells exposed to water-soluble fraction of particulate matter (PM10)

Exposure to atmospheric particulate matter (PM) is recognized as a human health risk factor of great concern. The present work aimed to study the cellular mechanisms underlying cytotoxic effects of airborne particulate matter <10 µm in size (PM₁₀), sampled in an urban background site from January to May 2020, on A549 cells. In particular, the study addressed if PM₁₀ exposure can be a main factor in the induction of the Apoptotic Volume Decrease (AVD), which is one of the first events of apoptosis, and if the generation of intracellular oxidative stress can be involved in the PM₁₀ induction of apoptosis in A549 cells. The cytotoxicity of PM₁₀ samples was measured by MTT test on cells exposed for 24 h to the PM₁₀ aqueous extracts, cell volume changes were monitored by morphometric analysis of the cells, apoptosis appearance was detected by annexin V and the induction of intracellular oxidative stress was evaluated by the ROS sensitive CM-H₂DCFDA fluorescent probe. The results showed cytotoxic effects ascribable to apoptotic death in A549 cells exposed for 24 h to aqueous extracts of airborne winter PM₁₀ samples characterized by high PM₁₀ value and organic carbon content. The detected reduced cell viability in winter samples ranged from 55% to 100%. Normotonic cell volume reduction (ranging from about 60% to 30% cell volume decrease) after PM₁₀ exposure was already detectable after the first 30 min clearly indicating the ability of PM₁₀, mainly arising from biomass burning, to induce Apoptotic Volume Decrease (AVD) in A549 cells. AVD was prevented by the pre-treatment with 0.5 mM SITS indicating the activation of Cl^- efflux presumably through the activation of VRAC channels. The exposure of A549 cells to PM₁₀ aqueous extracts was able to induce intracellular oxidative stress detected by using the ROS-sensitive probe CM-H₂DCFDA. The PM₁₀-induced oxidative stress was statistically significantly correlated with cell viability inhibition and with apoptotic cell shrinkage. It was already evident after 15 min exposure representing one of the first cellular effects caused by PM exposure. This result suggests the role of oxidative stress in the PM₁₀ induction of AVD as one of the first steps in cytotoxicity.

Long-term human spaceflight and inflammaging: Does it promote aging?

Spaceflight and its associated stressors, such as microgravity, radiation exposure, confinement, circadian derailment and disruptive workloads represent an unprecedented type of exposome that is entirely novel from an evolutionary stand point. Within this perspective, we aimed to review the effects of prolonged spaceflight on immune-neuroendocrine systems, brain and brain-gut axis, cardiovascular system and musculoskeletal apparatus, highlighting in particular the similarities with an accelerated aging process. In particular, spaceflight-induced muscle atrophy/sarcopenia and bone loss, vascular and metabolic changes, hyper and hypo reaction of innate and adaptive immune system appear to be modifications shared with the aging process. Most of these modifications are mediated by molecular events that include oxidative and mitochondrial stress, autophagy, DNA damage repair and telomere length alteration, among others, which directly or indirectly converge on the activation of an inflammatory response. According to the inflammaging theory of aging, such an inflammatory response could be a driver of an acceleration of the normal, physiological rate of aging and it is likely that all the systemic modifications in turn lead to an increase of inflammaging in a sort of vicious cycle. The most updated countermeasures to fight these modifications will be also discussed in the light of their possible application not only for astronauts' benefit, but also for older adults on the ground.

The expression pattern of GDF15 in human brain changes during aging and in Alzheimer's disease

Introduction

Growth Differentiation Factor 15 (GDF15) is a mitochondrial-stress-responsive molecule whose expression strongly increases with aging and age-related diseases. However, its role in neurodegenerative diseases, including Alzheimer's disease (AD), is still debated.

Methods

We have characterized the expression of GDF15 in brain samples from AD patients and non-demented subjects (controls) of different ages.

Results

Although no difference in CSF levels of GDF15 was found between AD patients and controls, GDF15 was expressed in different brain areas and seems to be predominantly localized in neurons. The ratio between its mature and precursor form was higher in the frontal cortex of AD patients compared to age-matched controls (p < 0.05). Moreover, this ratio was even higher for centenarians (p < 0.01), indicating that aging also affects GDF15 expression and maturation. A lower expression of OXPHOS complexes I, III, and V in AD patients compared to controls was also noticed, and a positive correlation between GDF15 and IL-6 mRNA levels was observed. Finally, when GDF15 was silenced in vitro in dermal fibroblasts, a decrease in OXPHOS complexes transcript levels and an increase in IL-6 levels were observed.

Discussion

Although GDF15 seems not to be a reliable CSF marker for AD, it is highly expressed in aging and AD brains, likely as a part of stress response aimed at counteracting mitochondrial dysfunction and neuroinflammation.

P346 HEALTH LITERACY ASSESSMENT AND HOSPITAL LENGTH OF STAY: A RETROSPECTIVE STUDY

Background

Cardiovascular diseases (CDs) were the leading cause of death worldwide in 2020. The risk of increasing CD is related to low Health Literacy (HL). HL can be defined as the individual’s ability to understand and process health information. Low HL has a risk ratio of 1.90 on mortality and 1.35 on readmission. A low level of HL was related to poorer use of health care services. Several inconsistencies were found about the relationship between HL and Length of stay (LOS). Although CDs are increasing because of the aging population, HL is often underestimated in the hospital setting. For this reason, HL assessment is important to identify patients at risk of poor HL. Therefore, this study aimed to describe the HL level in inpatients with CDs and to analyze the relationship between HL and LOS

Method

A retrospective design was used to randomly select 134 patients with CDs in eight cardiovascular and internal medicine units of an Italian hospital from 10 January to 10 May 2021. Clinical data were collected using a nursing information system (NIS) and the hospital discharge register. Single Item Literacy Screener (SILS) was used to measure HL and was systematically reported on NIS.

Results

The mean age of the sample was 71.28 (SD 13.19); 59% were male. HL‘s mean score was 2.43 (SD 1.2). A statistically significant linear association (Spearman’s correlation coefficient) was observed between the HL score and LOS. Patients with inadequate HL were 50.7% and had a longer LOS than patients with adequate HL (mean 9.1 ± 7.1 Vs 7.2 ± 5.9 days respectively, p = 0.05).

Conclusion

HL is poor and has been shown to be associated with LOS. These results should be confirmed after considering other variables through multivariate analyses. These findings suggest that the adverse effects of low HL may extend into the inpatient cardiovascular setting

P345 HEALTH LITERACY AS A MEASURE OF NURSING COMPLEXITY OF CARE IN A DEPARTMENT OF CARDIOVASCULAR MEDICINE

Background

HL plays a fundamental role in patients’ healthcare. According to the American Medical Association, HL can be viewed as a stronger predictor of a person’s health status than age, education level, and race. HL concept has many implications for nursing; they are responsible for identifying the patient’s barriers to their health information’s comprehension and providing specific nursing interventions in minimizing barriers. Moreover, HL assessment is necessary to plan tailored interventions, improve their efficacy through patient–centered communication. As a part of the nursing process, the nursing diagnosis (ND) classifies patients according to their level of nursing dependency and can be predictive for the nursing workload. No studies have been conducted on the relationship between NDs and HL. We aimed to describe the prevalence and distribution of NDs on admission in patients with CDs and to analyze the relationship between HL and NDs.

Method

A retrospective design was used to randomly select 134 patients with CDs in eight cardiovascular and internal medicine units of an Italian hospital from 10 January to 10 May 2021. NDs were collected using a nursing information system (NIS). Single Item Literacy Screener (SILS) was used to measure HL and was systematically reported on NIS.

Results

A mean of 3.5 ± 2.3 nursing diagnosis per patient was identified. A statistically significant linear association (Spearman’s correlation coefficient) was observed between HL score and the number of NDs.

Conclusion

HL was associated with the number of NDs.

GDF15, an emerging key player in human aging

Growth differentiation factor 15 (GDF15) is recently emerging not only as a stress-related mitokine, but also as a key player in the aging process, being one of the most up-regulated protein with age and associated with a variety of age-related diseases (ARDs). Many data indicate that GDF15 has protective roles in several tissues during different stress and aging, thus playing a beneficial role in apparent contrast with the observed association with many ARDs. A possible detrimental role for this protein is then hypothesized to emerge with age. Therefore, GDF15 can be considered as a pleiotropic factor with beneficial activities that can turn detrimental in old age possibly when it is chronically elevated. In this review, we summarize the current knowledge on the biology of GDF15 during aging. We also propose GDF15 as a part of a dormancy program, where it may play a role as a mediator of defense processes aimed to protect from inflammatory damage and other stresses, according to the life history theory.

Efficacy and safety of methylphenidate on attention deficit hyperactivity disorder in children with Down syndrome

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a common co-morbidity that affects up to 44% of children with Down syndrome (DS). There is a need for reliable, good quality research on the use of methylphenidate within this population. The objective of this study is to report our experience regarding the management of ADHD in these children using methylphenidate.

METHODS

This study is a retrospective observation of 21 children with DS, followed at Jérôme Lejeune Institute between 2000 and 2018. The diagnosis of ADHD was made using the Diagnostic and Statistical Manual of Mental Disorders criteria. Efficacy was measured as response or non-response on two main symptoms: attention/concentration and hyperactivity/impulsivity. Safety was evaluated by the presence or absence of side effects.

RESULTS

Sixteen out of the 21 children (76%) showed improvement with methylphenidate. The average age of treatment onset in responding children was 8 years and 10 months versus 6 years and 3 months in non-responders (P = 0.05). Average dose/weight was significantly different in responders and non-responders (0.82 vs. 0.54 mg/kg/day, respectively; P = 0.03). Twelve children out of 21 (57%) experienced side effects; only three experienced side effects severe enough to require treatment interruption. Most common side effects were loss of appetite and difficulties in falling asleep.

CONCLUSION

Methylphenidate was effective and safe in treating ADHD in 76% of cases in children with DS, with few serious side effects to report. Early diagnosis of ADHD is important to improve the quality of life, learning, inclusion and socialisation of children with DS.

Age-related alterations in muscle architecture are a signature of sarcopenia: the ultrasound sarcopenia index

BACKGROUND

The assessment of muscle mass is a key determinant of the diagnosis of sarcopenia. We introduce for the first time an ultrasound imaging method for diagnosing sarcopenia based on changes in muscle geometric proportions.

METHODS

Vastus lateralis muscle fascicle length (Lf) and thickness (Tm) were measured at 35% distal femur length by ultrasonography in a population of 279 individuals classified as moderately active elderly (MAE), sedentary elderly (SE) (n = 109), mobility impaired elderly (MIE) (n = 43), and in adult young controls (YC) (n = 60). The ratio of Lf/Tm was calculated to obtain an ultrasound index of the loss of muscle mass associated with sarcopenia (USI). In a subsample of elderly male individuals (n = 76) in which corresponding DXA measurements were available (MAE, n = 52 and SE, n = 24), DXA-derived skeletal muscle index (SMI, appendicular limb mass/height2 ) was compared with corresponding USI values.

RESULTS

For both young and older participants, USI values were found to be independent of sex, height and body mass. USI values were 3.70 ± 0.52 for YC, 4.50 ± 0.72 for the MAE, 5.05 ± 1.11 for the SE and 6.31 ± 1.38 for the MIE, all significantly different between each other (P < 0.0001). Based on the USI Z-scores, with reference to the YC population, the 219 elderly participants were stratified according to their muscle sarcopenic status. Individuals with USI values within a range of 3.70 < USI ≥ 4.23 were classified as non-sarcopenic (prevalence 23.7%), those with USI values within 4.23 < USI ≥ 4.76 were classified as pre-sarcopenic (prevalence 23.7%), those with USI values within 4.76 < USI ≥ 5.29 were classified as moderately sarcopenic (prevalence 15.1%), those with USI values within range 5.29 < USI ≥ 5.82 were classified as sarcopenic (prevalence 27.9%), and those with USI values >5.82 were classified as severely sarcopenic (prevalence 9.6%). The DXA-derived SMI was found to be significantly correlated with USI (r = 0.61, P < 0.0001). Notably, the USI cut-off value for moderate sarcopenia (4.76 a.u.) was found to coincide with the DXA cut-off value of sarcopenia (7.26 kg/m2 ).

CONCLUSIONS

We propose a novel, practical, and inexpensive imaging marker of the loss of muscle mass associated with sarcopenia, called the ultrasound sarcopenic index (USI), based on changes in muscle geometric proportions. These changes provide a useful 'signature of sarcopenia' and allow the stratification of individuals according to the presence and severity of muscle sarcopenia. We are convinced that the USI will be a useful clinical tool for confirming the diagnosis of sarcopenia, of which the assessment of muscle mass is a key-component.

Expression pattern of perilipins in human brain during aging and in Alzheimer's disease

AIMS

Perilipins are conserved proteins that decorate intracellular lipid droplets and are essential for lipid metabolism. To date, there is limited knowledge on their expression in human brain or their involvement in brain aging and neurodegeneration. The aim of this study was to characterise the expression levels of perilipins (Plin1-Plin5) in different cerebral areas from subjects of different age, with or without signs of neurodegeneration.

METHODS

We performed real-time RT-PCR, western blotting, immunohistochemistry and confocal microscopy analyses in autoptic brain samples of frontal and temporal cortex, cerebellum and hippocampus from subjects ranging from 33 to 104 years of age, with or without histological signs of neurodegeneration. To test the possible relationship between Plins and inflammation, correlation analysis with IL-6 expression was also performed.

RESULTS

Plin2, Plin3 and Plin5, but not Plin1 and Plin4, are expressed in the considered brain areas with different intensities. Plin2 appears to be expressed more in grey matter, particularly in neurons in all the areas analysed, whereas Plin3 and Plin5 appear to be expressed more in white matter. Plin3 seems to be expressed more in astrocytes. Only Plin2 expression is higher in old subjects and patients with early tauopathy or Alzheimer's disease and is associated with IL-6 expression.

CONCLUSIONS

Perilipins are expressed in human brain but only Plin2 appears to be modulated with age and neurodegeneration and linked to an inflammatory state. We propose that the accumulation of lipid droplets decorated with Plin2 occurs during brain aging and that this accumulation may be an early marker and initial step of inflammation and neurodegeneration.

Circulating miR-19a-3p and miR-19b-3p characterize the human aging process and their isomiRs associate with healthy status at extreme ages

Blood circulating microRNAs (c-miRs) are potential biomarkers to trace aging and longevity trajectories to identify molecular targets for anti-aging therapies. Based on a cross-sectional study, a discovery phase was performed on 12 donors divided into four groups: young, old, healthy, and unhealthy centenarians. The identification of healthy and unhealthy phenotype was based on cognitive performance and capabilities to perform daily activities. Small RNA sequencing identified 79 differentially expressed c-miRs when comparing young, old, healthy centenarians, and unhealthy centenarians. Two miRs, that is, miR-19a-3p and miR-19b-3p, were found increased at old age but decreased at extreme age, as confirmed by RT-qPCR in 49 donors of validation phase. The significant decrease of those miR levels in healthy compared to unhealthy centenarians appears to be due to the presence of isomiRs, not detectable with RT-qPCR, but only with a high-resolution technique such as deep sequencing. Bioinformatically, three main common targets of miR-19a/b-3p were identified, that is, SMAD4, PTEN, and BCL2L11, converging into the FoxO signaling pathway, known to have a significant role in aging mechanisms. For the first time, this study shows the age-related increase of plasma miR-19a/b-3p in old subjects but a decrease in centenarians. This decrease is more pronounced in healthy centenarians and was confirmed by the modified pattern of isomiRs comparing healthy and unhealthy centenarians. Thus, our study paves the way for functional studies using c-miRs and isomiRs as additional parameter to track the onset of aging and age-related diseases using new potential biomarkers.

The acoustical properties of tetraethyl orthosilicate based granular silica aerogels

Available data suggests that granulated aerogels can be of interest in terms of their sound absorption performance in the audio frequency range. However, there is still no thorough understanding of the complex physical phenomena which are responsible for their observed acoustical properties. This work is an attempt to address this gap through advanced material characterization methods and mathematical modelling. Aerogel samples are produced through a two-step, acid-base sol-gel process, with sol silica concentration and density being the main variables. Their pore structure is carefully characterized by nitrogen sorption analysis and scanning electron microscopy. The acoustical properties of hard-backed granular silica aerogels are measured in an impedance tube and the results predicted accurately with the adopted theoretical model. Although silica aerogels have over 90% of open interconnected pores, this was neither reflected in the measured acoustical properties nor the parameter values predicted with the model. Novel results show that only a proportion of the micro and mesopores in the direct vicinity of the grain surface influenced the acoustical properties of aerogels. Further work in the hierarchical pore structure of aerogels is required to better understand the roles of different pore scales on the measured acoustical properties of a granulated aerogel.

Circulating perilipin 2 levels are associated with fat mass, inflammatory and metabolic markers and are higher in women than men

Perilipin 2 (PLIN2) is a protein involved in lipid storage and metabolism in non-adipose tissues. Detectable levels of circulating PLIN2 (cPLIN2) have been reported to be associated with some types of cancer, but no systematic analysis of age-related modifications in cPLIN2 levels has ever been performed. We measured serum cPLIN2 in a group of old people including centenarians in comparison with young subjects and tested possible correlations with parameters of body composition, fat and glucose metabolism, and inflammation. We found that: i. levels of cPLIN2 do not change with age, but women have higher levels of cPLIN2 with respect to men; ii. cPLIN2 levels strongly correlate to BMI, as well as fat and lean mass; iii. cPLIN2 levels strongly correlate with the proinflammatory adipokine leptin. Due to the adipogenic activity of leptin, it is hypothesized that cPLIN2 is affected and possibly regulated by this pleiotropic adipokine. Moreover, these results suggest that cPLIN2 (possibly together with leptin) could be assumed as a proxy for body adiposity.

Evaluation and predictive value of IgE responses toward a comprehensive panel of house dust mite allergens using a new multiplex assay: a real-life experience on an Italian population

Summary

Background. House dust mites (HDM) are among the most important allergen sources worldwide, representing a major cause of perennial allergic rhinitis and asthma. Aim. To evaluate the prevalence of IgE responses towards a comprehensive panel of HDM allergens and to evaluate the implications of molecular sensitization profiles on respiratory symptoms. Methods. 155 consecutive HDM-allergic patients (mean age: 27.5 years; range: 1-62; female: 63), 86 affected by rhinitis and 68 by asthma, were enrolled. Specific IgE reactivity to Der f 1, Der p 1, Der f 2, Der p 2, Der p 5, Der p 7, Der p 10, Der p 11, Der p 20, Der p 21 and Der p 23 was tested in patients' sera using the last version of the multiparametric assay Allergy Explorer (ALEX). Results. In all, major and minor allergens were positive, respectively, in 96.8% and 50.9% of the patients. Prevalence and IgE levels of Der f 1, Der f 2, Der p 1 and Der p 20 were significantly higher in asthmatic patients (p less than 0.05), whereas subjects negative for minor allergens resulted more frequently suffering from rhinitis (p = 0.0001). Asthmatic patients had IgE reactivity to a larger number of HDM allergens (mean 5.4; SD ± 2.3) than patients with only rhinitis (mean 4.2; SD ± 2.5) (p = 0.003), whereas no differences in the number of HDM positive molecules and in the specific IgE levels were found among different ages. Conclusions. This study confirms that the assessment of IgE to a comprehensive panel of HDM allergens defines different serological reactivity profiles that seem associated with different clinical presentations.

Histochemical Characterisation and Gene Expression Analysis of Skeletal Muscles from Maremmana and Aubrac Steers Reared on Grazing and Feedlot Systems

Simple Summary

Muscle fibre types and sizes are important factors affecting muscle growth potential and meat quality. Their variability depends on some factors like muscle type, animal breed, physical activity, and they could be going through morphological or metabolic modifications, throughout animal life. Two muscles from Maremmana, an autochthonous breed from Tuscany (Italy), was compared to those from Aubrac, a breed from the Massif Central (France), under histochemical and gene expression points of view. Both these breeds were poorly studied, and the results identified Maremmana muscles were more oxidative in comparison to Aubrac. Moreover, steers of each breed were proportionally divided and reared on grazing or feedlot systems. Conversely to what was expected, the voluntary physical activity on pasture, another aspect poorly studied, influenced neither histochemical characteristics nor the gene expression.

Abstract

This study aimed to characterise the fibre composition of Triceps brachii (TB) and Semimembranosus (SM) muscles from 20 Maremmana (MA) and 20 Aubrac (AU) steers, and the effect of grazing activity in comparison with feedlot system. The histochemical method was performed with the m-ATPase method with an acid pre-incubation, thus allowing to distinguish type I, IIA, and IIB fibres. Additionally, on total RNA extracted from SM muscle, the expressions of atp1a1, mt-atp6, and capn1 genes were evaluated, in order to find potential associations with muscle fibre histochemical characteristics. In SM muscle, the MA steers had the greater frequency of oxidative fibres (type I and IIA) and the higher atp1a1 expression, in comparison to AU steers. Conversely, AU steers had a greater frequency of type IIB fibres, and the higher capn1 expression. A similar histochemical pattern was observed in TB muscle. The grazing activity was probably insufficient to determine differences both for fibre proportion and size, and gene expressions, except for mt-atp6 expression that was surprisingly highest in feedlot MA in comparison to other steers. These findings further the knowledge of muscle properties belonging to these breeds, and the effect of voluntary physical activity since few studies were available in this regard.

SARS-CoV-2 concentrations and virus-laden aerosol size distributions in outdoor air in north and south of Italy

The COVID-19 disease spread at different rates in the different countries and in different regions of the same country, as happened in Italy. Transmission by contact or at close range due to large respiratory droplets is widely accepted, however, the role of airborne transmission due to small respiratory droplets emitted by infected individuals (also asymptomatic) is controversial. It was suggested that outdoor airborne transmission could play a role in determining the differences observed in the spread rate. Concentrations of virus-laden aerosol are still poorly known and contrasting results are reported, especially for outdoor environments. Here we investigated outdoor concentrations and size distributions of virus-laden aerosol simultaneously collected during the pandemic, in May 2020, in northern (Veneto) and southern (Apulia) regions of Italy. The two regions exhibited significantly different prevalence of COVID-19. Genetic material of SARS-CoV-2 (RNA) was determined, using both real time RT-PCR and ddPCR, in air samples collected using PM₁₀ samplers and cascade impactors able to separate 12 size ranges from nanoparticles (diameter D < 0.056 µm) up to coarse particles (D > 18 µm). Air samples tested negative for the presence of SARS-CoV-2 at both sites, viral particles concentrations were <0.8 copies m^-3 in PM₁₀ and <0.4 copies m^-3 in each size range investigated. Outdoor air in residential and urban areas was generally not infectious and safe for the public in both northern and southern Italy, with the possible exclusion of very crowded sites. Therefore, it is likely that outdoor airborne transmission does not explain the difference in the spread of COVID-19 observed in the two Italian regions.

Inflammaging, hormesis and the rationale for anti-aging strategies

We propose in this review that hormesis, a concept profoundly and systematically addressed by Mark Mattson, has to be considered a sort of comprehensive "contact point" capable of unifying several conceptualizations of the aging process, including those focused on the stress response, oxidative stress and chronic inflammation/inflammaging. A major strength of hormesis and inflammaging is that they have a strong evolutionary basis. Moreover, both hormesis and inflammaging frame the aging process within a lifelong perspective of adaptation to different types of stresses. Such adaptation perspective also suggests that the aging process is malleable, and predicts that effective anti-aging strategies should mimic what evolution did in the course of million years and that we have to learn how to exploit the great potential inherent in the hormetic/inflammatory responses. To this regard, new topics such as the production of mitokines to cope with mitochondrial dysfunction are emerging as possible anti-aging target. This approach opens theoretically the door to the possibility of modulating the individual aging rate and trajectory by adopting the most effective scientifically-based lifestyle regarding fundamentally nutrition and physical activity. In this scenario Mark Mattson's lesson and personal example will permanently enlighten the aging field and the quest for a healthy aging and longevity.

Impact of epicardial adipose tissue increase after ST elevation Myocardial Infarction (STEMI) on IL-13 and left ventricular remodelling

Background

The role of epicardial adipose tissue (EAT) in myocardial diseases is well established, and several evidence suggest that EAT may negatively affect left ventricular (LV) remodelling through an imbalanced production and secretion of pro and anti-inflammatory cytokines. Of these, the IL-13 it is known to play a positive activity on cardiac remodelling. Nowadays, the crosstalk between EAT and the myocardium is still poorly understood and the effects of myocardial ischemia on morphological and functional properties of EAT are almost unknown.

Purpose

In the present study we explored whether an increase of EAT thickness after STEMI might be associated with unfavourable LV remodelling at 3 months (T1). We also evaluated the relationship between changes (Δ) of EAT thickness and systemic levels of Interleukin (IL)-13 which is known to play a favourable activity on LV remodelling after STEMI.

Methods

We enrolled 66 patients with first STEMI, undergoing primary percutaneous angioplasty. At baseline and at 3 months we performed a complete echocardiogram, including EAT maximal thickness assessment, and determined circulating levels of IL-13.

Results

At 3 months after STEMI, the population was stratified into two groups according to different EAT remodelling after cardiac event: Group 1, patients with an increased EAT thickness (Δ EAT&gt;1; 30 patients) and Group 2, patients with unchanged or decreased EAT thickness (Δ EAT&lt;1). The two groups did not differ for age, gender and atherosclerotic risk factors. Group 1 had a worse LV remodelling at 3 months with higher LV diastolic and systolic volumes, lower LV ejection fraction (p=0.003; p=0.013; p=0.013 respectively) and worse diastolic function (E/e'; p=0.011). Of interest, EAT thickness increase was paralleled by circulating IL-13 reduction (p=0.022).

Conclusion

Myocardial injury can result in EAT increase which is associated to worse LV remodelling probably through the loss of the protective role of IL-13.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This research has been funded by the University of Naples “Federico II” and “Compagnia di San Paolo e l'Istituto Banco di Napoli” within the competitive grant STAR 2018; Valentina Parisi is the principal investigator

Comparison of the impact of ships to size-segregated particle concentrations in two harbour cities of northern Adriatic Sea

Detailed information on in-harbour shipping contribution to size segregated particles in coastal cities are scarce, especially in the busy Mediterranean basin. This poses issues for human exposure and air quality in urban harbour agglomerates, where only criteria pollutants (i.e. PM₁₀ and/or PM_2.5) are usually monitored. In this work, particle number and mass size distributions, in a large size range (0.01-31 μm), were obtained in two coastal cities of northern Adriatic Sea: Venice (Italy) and Rijeka (Croatia). Three size ranges were investigated: nanoparticles (diameter D < 0.25 μm); fine particles (0.25<D < 1 μm), and coarse particles (D > 1 μm). Absolute concentrations were larger in Venice for all size ranges showing, using analysis of daily trends, a large influence of local meteorology and boundary-layer dynamics. Contribution of road transport was larger (in relative terms) in Rijeka compared to Venice. The highest contributions of shipping were in Venice, mainly because of the larger ship traffic. Maximum impact was on nanoparticles 7.4% (Venice) and 1.8% (Rijeka), the minimum was on fine range 1.9% (Venice) and <0.2% (Rijeka) and intermediate values were found in the coarse fraction 1.8% (Venice) and 0.5% (Rijeka). Contribution of shipping to mass concentration was not distinguishable from uncertainty in Rijeka (<0.2% for PM₁, PM_2.5, and PM₁₀) and was about 2% in Venice. Relative contributions as function of particles size show remarkable similitudes: a maximum for nanoparticles, a quick decrease and a successive secondary maximum (2-3 times lower than the first) in the fine range. For larger diameters, the relative contributions reach a minimum at 1-1.5 μm and there is a successive increase in the coarse range. Size distributions showed a not negligible contribution of harbour emissions to nanoparticle and fine particle number concentrations, compared to PM_2.5 or PM₁₀, indicating them as a better metric to monitor shipping impacts compared to mass concentrations (PM_2.5 or PM₁₀).

Disease-specific plasma levels of mitokines FGF21, GDF15, and Humanin in type II diabetes and Alzheimer's disease in comparison with healthy aging

Fibroblast Growth Factor 21 (FGF21), Growth Differentiation Factor 15 (GDF15), and Humanin (HN) are mitochondrial stress-related mitokines, whose role in health and disease is still debated. In this study, we confirmed that their plasma levels are positively correlated with age in healthy subjects. However, when looking at patients with type 2 diabetes (T2D) or Alzheimer's disease (AD), two age-related diseases sharing a mitochondrial impairment, we found that GDF15 is elevated in T2D but not in AD and represents a risk factor for T2D complications, while FGF21 and HN are lower in AD but not in T2D. Moreover, FGF21 reaches the highest levels in centenarian' offspring, a model of successful aging. As a whole, these data indicate that (i) the adaptive mitokine response observed in healthy aging is lost in age-related diseases, (ii) a common expression pattern of mitokines does not emerge in T2D and AD, suggesting an unpredicted complexity and disease-specificity, and (iii) FGF21 emerges as a candidate marker of healthy aging.

Exploring Relative Preferences for HIV Service Features Using Discrete Choice Experiments: a Synthetic Review

PURPOSE OF REVIEW

Aligning HIV treatment services with patient preferences can promote long-term engagement. A rising number of studies solicit such preferences using discrete choice experiments, but have not been systematically reviewed to seek generalizable insights. Using a systematic search, we identified eleven choice experiments evaluating preferences for HIV treatment services published between 2004 and 2020.

RECENT FINDINGS

Across settings, the strongest preference was for nice, patient-centered providers, for which participants were willing to trade considerable amounts of time, money, and travel distance. In low- and middle-income countries, participants also preferred collecting antiretroviral therapy (ART) less frequently than 1 monthly, but showed no strong preference for 3-compared with 6-month refill frequency. Facility waiting times and travel distances were also important but were frequently outranked by stronger preferences. Health facility-based services were preferred to community- or home-based services, but this preference varied by setting. In high-income countries, the availability of unscheduled appointments was highly valued. Stigma was rarely explored and costs were a ubiquitous driver of preferences. While present improvement efforts have focused on designs to enhance access (reduced waiting time, travel distance, and ART refill frequency), few initiatives focus on the patient-provider interaction, which represents a promising critical area for inquiry and investment. If HIV programs hope to truly deliver patient-centered care, they will need to incorporate patient preferences into service delivery strategies. Discrete choice experiments can not only inform such strategies but also contribute to prioritization efforts for policy-making decisions.

Both objective and paradoxical insomnia elicit a stress response involving mitokine production

Chronic insomnia is the most common sleep disorder in the elderly population. From 9 to 50% of patients suffer of paradoxical insomnia, with the same symptoms and ailments, though characterized by normal sleep patterns. We have investigated the level of parameters related to stress in a group of post-menopausal female patients (age range 55-70 years) suffering by either objective or paradoxical insomnia, in particular we have measured 24-hours urinary cortisol, allostatic load index, Perceived Stress Scale (PSS) score, and, for the first time, mitokines (mitochondrial stress response molecules) such as FGF21, GDF15 and Humanin (HN). Results show that the two groups are different as far as sleep efficiency score, as expected, but not for stress parameters, that in some cases resulted within the normality range, although quite close to the top threshold (such as cortisol) or much higher with respect to normality ranges (such as PSS). Therefore, the consequences of paradoxical insomnia on the expression of these parameters are the same as objective insomnia. As far as the level of mitokines, we showed that FGF21 and HN in particular resulted altered (decreased and increased, respectively) with respect to control population, however with no difference between the two groups of patients.

GDF15 Plasma Level Is Inversely Associated With Level of Physical Activity and Correlates With Markers of Inflammation and Muscle Weakness

Growth differentiation factor 15 (GDF15) is a stress molecule produced in response to mitochondrial, metabolic and inflammatory stress with a number of beneficial effects on metabolism. However, at the level of skeletal muscle it is still unclear whether GDF15 is beneficial or detrimental. The aim of the study was to analyse the levels of circulating GDF15 in people of different age, characterized by different level of physical activity and to seek for correlation with hematological parameters related to inflammation. The plasma concentration of GDF15 was determined in a total of 228 subjects in the age range from 18 to 83 years. These subjects were recruited and divided into three different groups based on the level of physical activity: inactive patients with lower limb mobility impairment, active subjects represented by amateur endurance cyclists, and healthy controls taken from the general population. Cyclists were sampled before and after a strenuous physical bout (long distance cycling race). The plasma levels of GDF15 increase with age and are inversely associated with active lifestyle. In particular, at any age, circulating GDF15 is significantly higher in inactive patients and significantly lower in active people, such as cyclists before the race, with respect to control subjects. However, the strenuous physical exercise causes in cyclists a dramatic increase of GDF15 plasma levels, that after the race are similar to that of patients. Moreover, GDF15 plasma levels significantly correlate with quadriceps torque in patients and with the number of total leukocytes, neutrophils and lymphocytes in both cyclists (before and after race) and patients. Taken together, our data indicate that GDF15 is associated with decreased muscle performance and increased inflammation.

X-chromosome-linked miR548am-5p is a key regulator of sex disparity in the susceptibility to mitochondria-mediated apoptosis

Sex dimorphism in cell response to stress has previously been investigated by different research groups. This dimorphism could be at least in part accounted for by sex-biased expression of regulatory elements such as microRNAs (miRs). In order to spot previously unknown miR expression differences we took advantage of prior knowledge on specialized databases to identify X chromosome-encoded miRs potentially escaping X chromosome inactivation (XCI). MiR-548am-5p emerged as potentially XCI escaper and was experimentally verified to be significantly up-regulated in human XX primary dermal fibroblasts (DFs) compared to XY ones. Accordingly, miR-548am-5p target mRNAs, e.g. the transcript for Bax, was differently modulated in XX and XY DFs. Functional analyses indicated that XY DFs were more prone to mitochondria-mediated apoptosis than XX ones. Experimentally induced overexpression of miR548am-5p in XY cells by lentivirus vector transduction decreased apoptosis susceptibility, whereas its down-regulation in XX cells enhanced apoptosis susceptibility. These data indicate that this approach could be used to identify previously unreported sex-biased differences in miR expression and that a miR identified with this approach, miR548am-5p, can account for sex-dependent differences observed in the susceptibility to mitochondrial apoptosis of human DFs.

Accelerated bio-cognitive aging in Down syndrome: State of the art and possible deceleration strategies

Down syndrome (DS) has been proposed by George Martin as a segmental progeroid syndrome since 1978. In fact, DS persons suffer from several age‐associated disorders much earlier than euploid persons. Furthermore, a series of recent studies have found that DS persons display elevated levels of age biomarkers, thus supporting the notion that DS is a progeroid trait. Nowadays, due to the progressive advancements in social inclusion processes and medical assistance, DS persons live much longer than in the past; therefore, the early‐onset health problems of these persons are becoming an urgent and largely unmet social and medical burden. In particular, the most important ailment of DS persons is the accelerated cognitive decline that starts when they reach about 40 years of age. This decline can be at least in part counteracted by multi‐systemic approaches including early‐onset cognitive training, physical activity, and psychosocial assistance. However, no pharmacological treatment is approved to counteract this decline. According to the most advanced conceptualization of Geroscience, tackling the molecular mechanisms underpinning the aging process should be a smart/feasible strategy to combat and/or delay the great majority of age‐related diseases, including cognitive decline. We think that a debate is needed urgently on if (and how) this strategy could be integrated in protocols to face DS‐associated dementia and overall unhealthy aging. In particular we propose that, on the basis of data obtained in different clinical settings, metformin is a promising candidate that could be exploited to counteract cognitive decline in DS.

Muscle-specific Perilipin2 down-regulation affects lipid metabolism and induces myofiber hypertrophy

BACKGROUND

Perilipin2 (Plin2) belongs to a family of five highly conserved proteins, known for their role in lipid storage. Recent data indicate that Plin2 has an important function in cell metabolism and is involved in several human pathologies, including liver steatosis and Type II diabetes. An association between Plin2 and lower muscle mass and strength has been found in elderly and inactive people, but its function in skeletal muscle is still unclear. Here, we addressed the role of Plin2 in adult muscle by gain and loss of function experiments.

METHODS

By mean of in vivo Plin2 down-regulation (shPlin2) and overexpression (overPlin2) in murine tibialis anterior muscle, we analysed the effects of Plin2 genetic manipulations on myofiber size and lipid composition. An analysis of skeletal muscle lipid composition was also performed in vastus lateralis samples from young and old patients undergoing hip surgery.

RESULTS

We found that Plin2 down-regulation was sufficient to induce a 30% increase of myofiber cross-sectional area, independently of mTOR pathway. Alterations of lipid content and modulation of genes involved in lipid synthesis occurred in hypertrophic muscles. In particular, we showed a decrease of triglycerides, ceramides, and phosphatidylcoline:phosphatidylethanolamine ratio, a condition known to impact negatively on muscle function. Plin2 overexpression did not change fibre size; however, lipid composition was strongly affected in a way that is similar to that observed in human samples from old patients.

CONCLUSIONS

Altogether these data indicate that Plin2 is a critical mediator for the control of muscle mass, likely, but maybe not exclusively, through its critical role in the regulation of intracellular lipid content and composition.

Recovery from 6-month spaceflight at the International Space Station: muscle-related stress into a proinflammatory setting

The Sarcolab pilot study of 2 crewmembers, investigated before and after a 6-mo International Space Station mission, has demonstrated the substantial muscle wasting and weakness, along with disruption of muscle's oxidative metabolism. The present work aimed at evaluating the pro/anti-inflammatory status in the same 2 crewmembers (A, B). Blood circulating (c-)microRNAs (miRs), c-proteasome, c-mitochondrial DNA, and cytokines were assessed by real-time quantitative PCR or ELISA tests. Time series analysis was performed ( i.e., before flight and after landing) at 1 and 15 d of recovery (R+1 and R+15, respectively). C-biomarkers were compared with an age-matched control population and with 2-dimensional proteomic analysis of the 2 crewmembers' muscle biopsies. Striking differences were observed between the 2 crewmembers at R+1, in terms of inflamma-miRs (c-miRs-21-5p, -126-3p, and -146a-5p), muscle specific (myo)-miR-206, c-proteasome, and IL-6/leptin, thus making the 2 astronauts dissimilar to each other. Final recovery levels of c-proteasome, c-inflamma-miRs, and c-myo-miR-206 were not reverted to the baseline values in crewmember A. In both crewmembers, myo-miR-206 changed significantly after recovery. Muscle biopsy of astronaut A showed an impressive 80% increase of α-1-antitrypsin, a target of miR-126-3p. These results point to a strong stress response induced by spaceflight involving muscle tissue and the proinflammatory setting, where inflamma-miRs and myo-miR-206 mediate the systemic recovery phase after landing.-Capri, M., Morsiani, C., Santoro, A., Moriggi, M., Conte, M., Martucci, M., Bellavista, E., Fabbri, C., Giampieri, E., Albracht, K., Flück, M., Ruoss, S., Brocca, L., Canepari, M., Longa, E., Di Giulio, I., Bottinelli, R., Cerretelli, P., Salvioli, S., Gelfi, C., Franceschi, C., Narici, M., Rittweger, J. Recovery from 6-month spaceflight at the International Space Station: muscle-related stress into a proinflammatory setting.

Aging and Imaging Assessment of Body Composition: From Fat to Facts

The aging process is characterized by the chronic inflammatory status called "inflammaging", which shares major molecular and cellular features with the metabolism-induced inflammation called "metaflammation." Metaflammation is mainly driven by overnutrition and nutrient excess, but other contributing factors are metabolic modifications related to the specific body composition (BC) changes occurring with age. The aging process is indeed characterized by an increase in body total fat mass and a concomitant decrease in lean mass and bone density, that are independent from general and physiological fluctuations in weight and body mass index (BMI). Body adiposity is also re-distributed with age, resulting in a general increase in trunk fat (mainly abdominal fat) and a reduction in appendicular fat (mainly subcutaneous fat). Moreover, the accumulation of fat infiltration in organs such as liver and muscles also increases in elderly, while subcutaneous fat mass tends to decrease. These specific variations in BC are considered risk factors for the major age-related diseases, such as cardiovascular diseases, type 2 diabetes, sarcopenia and osteoporosis, and can predispose to disabilities. Thus, the maintenance of a balance rate of fat, muscle and bone is crucial to preserve metabolic homeostasis and a health status, positively contributing to a successful aging. For this reason, a detailed assessment of BC in elderly is critical and could be an additional preventive personalized strategy for age-related diseases. Despite BMI and other clinical measures, such as waist circumference measurement, waist-hip ratio, underwater weighing and bioelectrical impedance, are widely used as a surrogate measure for body adiposity, they barely reflect the distribution of body fat. Because of the great advantages offered by imaging tools in research and clinics, the attention of clinicians is now moving to powerful imaging techniques such as computed tomography, magnetic resonance imaging, dual-energy X-ray absorptiometry and ultrasound to obtain a more accurate estimation of BC. The aim of this review is to present the state of the art of the imaging techniques that are currently available to measure BC and that can be applied to the study of BC changes in the elderly, outlining advantages and disadvantages of each technique.

The Dual Role of the Pervasive "Fattish" Tissue Remodeling With Age

Human aging is characterized by dramatic changes in body mass composition that include a general increase of the total fat mass. Within the fat mass, a change in the proportions of adipose tissues also occurs with aging, affecting body metabolism, and playing a central role in many chronic diseases, including insulin resistance, obesity, cardiovascular diseases, and type II diabetes. In mammals, fat accumulates as white (WAT) and brown (BAT) adipose tissue, which differ both in morphology and function. While WAT is involved in lipid storage and immuno-endocrine responses, BAT is aimed at generating heat. With advancing age BAT declines, while WAT increases reaching the maximum peak by early old age and changes its distribution toward a higher proportion of visceral WAT. However, lipids tend to accumulate also within lipid droplets (LDs) in non-adipose tissues, including muscle, liver, and heart. The excess of such ectopic lipid deposition and the alteration of LD homeostasis contribute to the pathogenesis of the above-mentioned age-related diseases. It is not clear why age-associated tissue remodeling seems to lean toward lipid deposition as a "default program." However, it can be noted that such remodeling is not inevitably detrimental. In fact, such a programmed redistribution of fat throughout life could be considered physiological and even protective, in particular at extreme old age. In this regard, it has to be considered that an excessive decrease of subcutaneous peripheral fat is associated with a pro-inflammatory status, and a decrease of LD is associated with lipotoxicity leading to an increased risk of insulin resistance, type II diabetes and cardiovascular diseases. At variance, a balanced rate of fat content and distribution has beneficial effects for health and metabolic homeostasis, positively affecting longevity. In this review, we will summarize the present knowledge on the mechanisms of the age-related changes in lipid distribution and we will discuss how fat mass negatively or positively impacts on human health and longevity.

Hypercoagulable State in Patients with Advanced Gastrointestinal Cancer: Evidence for an Acquired Resistance to Activated Protein C

Aims and background

Thromboembolic complications are common in patients with cancer and represent the second cause of death in patients with overt malignant disease. The aim of this study was to investigate the activated protein C pathway in cancer.

Methods

We studied the coagulation cascade, natural clotting inhibitors, fibrinolytic proteins and resistance to activated protein C in 20 patients with advanced gastrointestinal cancer and 84 volunteers by measuring PT, APTT, fibrinogen, AT III, PC, PS, APC resistance, fibrinolytic system (PLG, ANPL, PAI-1 and t-PA) and activation peptides (D-Dimers, prothrombin 0 fragment 1+2/F1+2).

Results

Laboratory tests confirmed coagulation abnormalities in cancer patients. Fibrinogen, D-Dimers and F1+2 were increased, while t-PA activity was significantly lower than that of controls. APC resistance was higher in cancer patients compared to the control group (55% vs 2%; P < 0.0001). Excess thrombin generation was manifested by increased F1+2 plasma levels in APC-resistant cancer patients. Genetic analyses showed that only one patient with a poor response to APC carried a factor V R506Q mutation in exon 10.

Conclusions

Our findings show a high prevalence of APC resistance in cancer, compatible with an acquired defect in the APC pathway.

The Continuum of Aging and Age-Related Diseases: Common Mechanisms but Different Rates

Geroscience, the new interdisciplinary field that aims to understand the relationship between aging and chronic age-related diseases (ARDs) and geriatric syndromes (GSs), is based on epidemiological evidence and experimental data that aging is the major risk factor for such pathologies and assumes that aging and ARDs/GSs share a common set of basic biological mechanisms. A consequence is that the primary target of medicine is to combat aging instead of any single ARD/GSs one by one, as favored by the fragmentation into hundreds of specialties and sub-specialties. If the same molecular and cellular mechanisms underpin both aging and ARDs/GSs, a major question emerges: which is the difference, if any, between aging and ARDs/GSs? The hypothesis that ARDs and GSs such as frailty can be conceptualized as accelerated aging will be discussed by analyzing in particular frailty, sarcopenia, chronic obstructive pulmonary disease, cancer, neurodegenerative diseases such as Alzheimer and Parkinson as well as Down syndrome as an example of progeroid syndrome. According to this integrated view, aging and ARDs/GSs become part of a continuum where precise boundaries do not exist and the two extremes are represented by centenarians, who largely avoided or postponed most ARDs/GSs and are characterized by decelerated aging, and patients who suffered one or more severe ARDs in their 60s, 70s, and 80s and show signs of accelerated aging, respectively. In between these two extremes, there is a continuum of intermediate trajectories representing a sort of gray area. Thus, clinically different, classical ARDs/GSs are, indeed, the result of peculiar combinations of alterations regarding the same, limited set of basic mechanisms shared with the aging process. Whether an individual will follow a trajectory of accelerated or decelerated aging will depend on his/her genetic background interacting lifelong with environmental and lifestyle factors. If ARDs and GSs are manifestations of accelerated aging, it is urgent to identify markers capable of distinguishing between biological and chronological age to identify subjects at higher risk of developing ARDs and GSs. To this aim, we propose the use of DNA methylation, N-glycans profiling, and gut microbiota composition to complement the available disease-specific markers.

Malignant ovarian germ cell tumors in pediatric patients: The AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica) study

OBJECTIVE

Malignant ovarian germ cell tumors (MOGCT) carry an excellent prognosis, and the treatment aims to achieve results with the least possible treatment-related morbidity. The aim of this study was to assess the outcomes of pediatric patients with MOGCT.

METHODS

Patients were treated according to their stage: surgery and surveillance for stage I; a modified bleomycin-etoposide-cisplatin (BEP) regimen for stages II (three cycles), III, and IV (three cycles) with surgery on residual disease.

RESULTS

Seventy-seven patients were enrolled (median age 11.8 years), 26 with dysgerminoma (Dysg), 13 with immature teratoma and elevated serum alpha-fetoprotein levels (IT + AFP), and 38 with nondysgeminoma (Non-Dysg) staged as follows: 27 stage I, 13 stage II, 32 stage III, 5 stage IV. Among evaluable patients in stage I (5-year event-free survival [EFS] 72.1% [95% CI: 56.4-92.1%]; 5-year overall survival [OS] 100%), seven relapsed (three patients with Dysg and four patients with Non-Dysg) and were rescued with chemotherapy (plus surgery in three patients). Among the evaluable patients with stages II-IV, 48 (98%) achieved complete remission after chemotherapy ± surgery, one (IT + AFP, stage IV) had progressive disease. In the whole series (median follow-up 80 months), the 5-year OS and EFS were 98.5% (95% CI: 95.6-100%) and 84.5% (95% CI: 76.5-93.5%).

CONCLUSIONS

We confirm the excellent outcome for MOGCT. Robust data are lacking on surgical staging, surveillance for Non-Dysg with stage I, the management of IT + AFP, and the most appropriate BEP regimen. As pediatric oncologists, we support the role of surveillance after proper surgical staging providing cases are managed by experts at specialized pediatric centers.

Salvage total laryngectomy after conservation laryngeal surgery for recurrent laryngeal squamous cell carcinoma

The aim of the present study was to evaluate the oncological efficacy of salvage total laryngectomy in patients who had previously undergone supracricoid partial laryngectomy or transoral laser microsurgery for treatment of laryngeal squamous cell carcinoma. We retrospectively reviewed the medical, surgical and pathological records of 35 patients who underwent salvage total laryngectomy after recurrence of laryngeal cancer (following supracricoid partial laryngectomy or transoral laser microsurgery). Kaplan-Meier survival curves as well as univariate and multivariate analyses of prognostic factors were performed. No statistically significant differences were seen comparing the supracricoid partial laryngectomy group with the transoral laser microsurgery group for overall survival and disease-specific survival at 3 years (OS = 38% vs. 52%, p = 0.16; DSS = 40% vs. 61%, p = 0.057) or locoregional control at 2 years (LRC = 40% vs. 54%, p = 0.056). A trend indicating worse survival and locoregional control for supracricoid partial laryngectomy patients emerged. Preservation of the osteocartilaginous frame in transoral laser microsurgery could hypothetically result in better salvageability of anterior recurrences with extralaryngeal spread.

Age-Associated Loss of OPA1 in Muscle Impacts Muscle Mass, Metabolic Homeostasis, Systemic Inflammation, and Epithelial Senescence

Mitochondrial dysfunction occurs during aging, but its impact on tissue senescence is unknown. Here, we find that sedentary but not active humans display an age-related decline in the mitochondrial protein, optic atrophy 1 (OPA1), that is associated with muscle loss. In adult mice, acute, muscle-specific deletion of Opa1 induces a precocious senescence phenotype and premature death. Conditional and inducible Opa1 deletion alters mitochondrial morphology and function but not DNA content. Mechanistically, the ablation of Opa1 leads to ER stress, which signals via the unfolded protein response (UPR) and FoxOs, inducing a catabolic program of muscle loss and systemic aging. Pharmacological inhibition of ER stress or muscle-specific deletion of FGF21 compensates for the loss of Opa1, restoring a normal metabolic state and preventing muscle atrophy and premature death. Thus, mitochondrial dysfunction in the muscle can trigger a cascade of signaling initiated at the ER that systemically affects general metabolism and aging.

Conserved and species-specific molecular denominators in mammalian skeletal muscle aging

Aging is a complex phenomenon involving functional decline in multiple physiological systems. We undertook a comparative analysis of skeletal muscle from four different species, i.e. mice, rats, rhesus monkeys, and humans, at three different representative stages during their lifespan (young, middle, and old) to identify pathways that modulate function and healthspan. Gene expression profiling and computational analysis revealed that pathway complexity increases from mice to humans, and as mammals age, there is predominantly an upregulation of pathways in all species. Two downregulated pathways, the electron transport chain and oxidative phosphorylation, were common among all four species in response to aging. Quantitative PCR, biochemical analysis, mitochondrial DNA measurements, and electron microscopy revealed a conserved age-dependent decrease in mitochondrial content, and a reduction in oxidative phosphorylation complexes in monkeys and humans. Western blot analysis of key proteins in mitochondrial biogenesis discovered that (i) an imbalance toward mitochondrial fusion occurs in aged skeletal muscle and (ii) mitophagy is not overtly affected, presumably leading to the observed accumulation of abnormally large, damaged mitochondria with age. Select transcript expression analysis uncovered that the skeletal inflammatory profile differentially increases with age, but is most pronounced in humans, while increased oxidative stress (as assessed by protein carbonyl adducts and 4-hydroxynonenal) is common among all species. Expression studies also found that there is unique dysregulation of the nutrient sensing pathways among the different species with age. The identification of conserved pathways indicates common molecular mechanisms intrinsic to health and lifespan, whereas the recognition of species-specific pathways emphasizes the importance of human studies for devising optimal therapeutic modalities to slow the aging process.

Aging is a complex phenomenon involving functional declines in multiple physiological systems with the passage of time. Focusing on skeletal muscle, a group of international scientists identified pathways involved in healthspan and by determining global gene expression profiles across species they exposed common mechanisms fundamental to the aging process. Their experimental design involved comparative analysis of mice, rats, rhesus monkeys and humans, targeting three key time points during their respective lifespans. Pathways related to oxidative stress, inflammation and nutrient signaling, which function collectively to affect the quality and status of mitochondria, emerged across all species in an age-influenced manner. The identification of conserved pathways reveals molecular mechanisms intrinsic to health and survival, whereas the unveiling of species-specific pathways emphasizes the importance of human studies for devising optimal therapeutic modalities to slow the aging process.