A critical appraisal of blood-based biomarkers for Alzheimer's disease.

Biomarkers that predict the clinical onset of Alzheimer's disease (AD) enable the identification of individuals in the early, preclinical stages of the disease. Detecting AD at this point may allow for more effective therapeutic interventions and optimized enrollment for clinical trials of novel drugs. The current biological diagnosis of AD is based on the AT(N) classification system with the measurement of brain deposition of amyloid-ß (Aß) ("A"), tau pathology ("T"), and neurodegeneration ("N"). Diagnostic cut-offs for Aß1-42, the Aß1-42/Aß1-40 ratio, tau and hyperphosphorylated-tau concentrations in cerebrospinal fluid have been defined and may support AD clinical diagnosis. Blood-based biomarkers of the AT(N) categories have been described in the AD continuum. Cross-sectional and longitudinal studies have shown that the combination of blood biomarkers tracking neuroaxonal injury (neurofilament light chain) and neuroinflammatory pathways (glial fibrillary acidic protein) enhance sensitivity and specificity of AD clinical diagnosis and improve the prediction of AD onset. However, no international accepted cut-offs have been identified for these blood biomarkers. A kit for blood Aß1-42/Aß1-40 is commercially available in the U.S.; however, it does not provide a diagnosis, but simply estimates the risk of developing AD. Although blood-based AD biomarkers have a great potential in the diagnostic work-up of AD, they are not ready for the routine clinical use.

Real-World Outcomes of Lip Augmentation Using a Hyaluronic Acid-Based Filler With Low 1,4-Butanediol Diglycidyl Ether Content: A Prospective, Open-Label, Multicenter, Post-marketing Study.

Background 1,4-butanediol diglycidyl ether (BDDE) is the most common cross-linker used to produce hyaluronic acid (HA)-based dermal fillers. However, BDDE may have cytotoxic and potentially mutagenic effects, raising safety concerns. Consequently, manufacturers are developing new HA filler formulations with reduced BDDE levels to mitigate potential biological risks. Here, we sought to evaluate the clinical outcomes of lip augmentation performed using an HA-based filler with a reduced BDDE content (Agex Fill Volume®; Biodue SpA, Barberino Tavarnelle, Italy) in a real-world clinical setting. Methods This was a prospective, open-label, multicenter, post-marketing study conducted over six months. Thirty adult subjects (29 women and one man) who desired a ≥1-point improvement on the validated Lip Fullness Scale 2 (LFS2) were enrolled. The primary efficacy endpoint was the post-procedural increase in the investigator-reported LFS2 compared to baseline. Other endpoints included self-perceived happiness assessed using the Happiness Measure Scale (HMS) and safety. Results Of the study participants, 73% (22/30) demonstrated an improvement of at least one point in their LFS2 scores immediately after treatment compared to baseline, thus qualifying as responders. Six months later, the responder rate, based on LFS2 scores, remained steady at 66.7% (20/30). Importantly, these aesthetic improvements were consistently associated with a positive impact on subject-reported HMS, with a significant difference (p < 0.001) between post-treatment and baseline scores. All adverse events (AEs) reported after treatment were mild. Conclusions Agex Fill Volume®, a HA filler with low BDDE content, provides a safe and effective option for enhancing lip volume in real-world aesthetic settings.

Clinically Actionable Topical Strategies for Addressing the Hallmarks of Skin Aging: A Primer for Aesthetic Medicine Practitioners.

In this narrative review, we sought to provide a comprehensive overview of the mechanisms underlying cutaneous senescence, framed by the twelve traditional hallmarks of aging. These include genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, impaired macroautophagy, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, altered intercellular communication, chronic inflammation, and dysbiosis. We also examined how topical interventions targeting these hallmarks can be integrated with conventional aesthetic medicine techniques to enhance skin rejuvenation. The potential of combining targeted topical therapies against the aging hallmarks with minimally invasive procedures represents a significant advancement in aesthetic medicine, offering personalized and effective strategies to combat skin aging. The reviewed evidence paves the way for future advancements and underscores the transformative potential of integrating scientifically validated interventions targeted against aging hallmarks into traditional aesthetic practices.

Digging into the intrinsic capacity concept: Can it be applied to Alzheimer's disease?

Historically, aging research has largely centered on disease pathology rather than promoting healthy aging. The World Health Organization's (WHO) policy framework (2015-2030) underscores the significance of fostering the contributions of older individuals to their families, communities, and economies. The WHO has introduced the concept of intrinsic capacity (IC) as a key metric for healthy aging, encompassing five primary domains: locomotion, vitality, sensory, cognitive, and psychological. Past AD research, constrained by methodological limitations, has focused on single outcome measures, sidelining the complexity of the disease. Our current scientific milieu, however, is primed to adopt the IC concept. This is due to three critical considerations: (I) the decline in IC is linked to neurocognitive disorders, including AD, (II) cognition, a key component of IC, is deeply affected in AD, and (III) the cognitive decline associated with AD involves multiple factors and pathophysiological pathways. Our study explores the application of the IC concept to AD patients, offering a comprehensive model that could revolutionize the disease's diagnosis and prognosis. There is a dearth of information on the biological characteristics of IC, which are a result of complex interactions within biological systems. Employing a systems biology approach, integrating omics technologies, could aid in unraveling these interactions and understanding IC from a holistic viewpoint. This comprehensive analysis of IC could be leveraged in clinical settings, equipping healthcare providers to assess AD patients' health status more effectively and devise personalized therapeutic interventions in accordance with the precision medicine paradigm. We aimed to determine whether the IC concept could be extended from older individuals to patients with AD, thereby presenting a model that could significantly enhance the diagnosis and prognosis of this disease.

Monitoring synaptic pathology in Alzheimer's disease through fluid and PET imaging biomarkers: a comprehensive review and future perspectives.

Alzheimer's disease (AD) is currently constrained by limited clinical treatment options. The initial pathophysiological event, which can be traced back to decades before the clinical symptoms become apparent, involves the excessive accumulation of amyloid-beta (Aß), a peptide comprised of 40-42 amino acids, in extraneuronal plaques within the brain. Biochemical and histological studies have shown that overaccumulation of Aß instigates an aberrant escalation in the phosphorylation and secretion of tau, a microtubule-binding axonal protein. The accumulation of hyperphosphorylated tau into intraneuronal neurofibrillary tangles is in turn correlated with microglial dysfunction and reactive astrocytosis, culminating in synaptic dysfunction and neurodegeneration. As neurodegeneration progresses, it gives rise to mild clinical symptoms of AD, which may eventually evolve into overt dementia. Synaptic loss in AD may develop even before tau alteration and in response to possible elevations in soluble oligomeric forms of Aß associated with early AD. These findings largely rely on post-mortem autopsy examinations, which typically involve a limited number of patients. Over the past decade, a range of fluid biomarkers such as neurogranin, α-synuclein, visinin-like protein 1 (VILIP-1), neuronal pentraxin 2, and ß-synuclein, along with positron emission tomography (PET) markers like synaptic vesicle glycoprotein 2A, have been developed. These advancements have facilitated the exploration of how synaptic markers in AD patients correlate with cognitive impairment. However, fluid biomarkers indicating synaptic loss have only been validated in cerebrospinal fluid (CSF), not in plasma, with the exception of VILIP-1. The most promising PET radiotracer, [11C]UCB-J, currently faces significant challenges hindering its widespread clinical use, primarily due to the necessity of a cyclotron. As such, additional research geared toward the exploration of synaptic pathology biomarkers is crucial. This will not only enable their extensive clinical application, but also refine the optimization process of AD pharmacological trials.

Prevalence of hepatic steatosis and fibrosis in apparently healthy airline pilots: A transient elastography study.

Background and Aim: Airline pilots (APs) are often characterized by a sedentary lifestyle, predisposing them to adverse cardiometabolic consequences. In this cross-sectional study, we used transient elastography (TE) to investigate the prevalence of hepatic steatosis and fibrosis among apparently healthy APs. Materials and Methods: The study cohort consisted of 137 male APs of Caucasian descent who voluntarily underwent TE. To evaluate the extent and severity of hepatic steatosis and fibrosis, we employed established cutoff values for the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM). Results: Of the APs, 34 (24.8%) were diagnosed with TE-defined steatosis. Specifically, 25 APs (18.2%) exhibited mild steatosis, 6 (4.4%) moderate steatosis, and 3 (2.2%) severe steatosis. The majority of participants (80 APs or 58.4%) showed no signs of liver fibrosis based on LSM values. However, 49 APs (35.8%) were diagnosed with mild fibrosis (F1), 7 (5.1%) with significant fibrosis (F2), and one (0.7%) with advanced fibrosis (F3). None of the pilots had F4 (cirrhosis). In multivariable linear regression analysis, BMI was the sole independent predictor of both CAP (ß=0.34, p<0.001) and LSM (ß=0.41, p<0.001) values in our sample of male APs. Conclusion: TE is a straightforward and convenient non-invasive method for detecting hepatic steatosis and fibrosis in high-risk occupational groups such as APs.

Evaluating the Serum Levels of Beclin-1 and Mammalian/Mechanistic Target of Rapamycin (mTOR) in Three Different Professional Categories.

BACKGROUND: The possible associations between occupational factors and autophagy - a catabolic process that is evolutionarily conserved and serves as a vital cornerstone in maintaining cellular balance - remain largely unexplored. OBJECTIVES: We assessed serum levels of beclin-1, a principal effector of autophagy, and the mammalian/mechanistic target of rapamycin (mTOR), a protein recognized for its part in suppressing autophagy, within a group of healthy individuals hailing from three different professional fields, each characterized by its unique working conditions. METHODS: A total of 60 men were recruited from three distinct occupational categories: airline pilots, construction laborers, and fitness trainers. Each group consisted of 20 subjects who were selected during routine occupational health appointments. Serum levels of beclin-1 and mTOR were measured using commercially available immunoassays and compared among the three categories. RESULTS: Fitness instructors had the highest concentration of beclin-1 (3.1 ± 0.9 ng/mL). Construction workers followed with a mean of 2.4 ± 0.4 ng/mL, while airline pilots had the lowest levels at 1.9 ± 0.5 ng/mL (one-way analysis of variance, P < 0.001). In terms of mTOR levels, construction workers had the highest concentration (5.9 ± 1.9 ng/mL), followed by airline pilots (4.4 ± 1.7 ng/mL). Fitness instructors, on the other hand, had the lowest mTOR levels (3.5 ± 1.2 ng/mL; one-way analysis of variance, P < 0.001). CONCLUSIONS: Serum levels of autophagy biomarkers can vary among healthy individuals based on their professional roles. Considering the crucial function autophagy serves in both health and disease, further investigations are crucial to deepen our comprehension of the potential implications of autophagy in the field of occupational medicine.

Impact of Job Types on Plasma Neurotrophins Levels: A Preliminary Study in Airline Pilots, Construction Workers, and Fitness Instructors.

BACKGROUND: Neurotrophins (NTs) encompass a group of closely associated proteins regulating various aspects of neuronal growth and survival. The potential association between work-related factors and the levels of circulating NTs has not been extensively examined. In this preliminary investigation, we evaluated plasma concentrations of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4) in a cohort of healthy individuals from three distinct professional categories, each with unique work environments and lifestyle factors. METHODS: The study involved 60 men from three professional fields: airline pilots, construction laborers, and fitness trainers (20 participants per category) recruited during routine occupational health appointments. Plasma levels of NTs were measured using commercially available immunoassays and compared in the three professional groups. RESULTS: Among the professions studied, fitness instructors displayed the highest concentrations of BDNF and NGF, with airline pilots ranking second, and construction workers showing the lowest levels. Significantly decreased NT-3 levels were observed in airline pilots compared to fitness instructors and construction workers, but no differences were found between the latter two occupations. NT-4 levels were similar across all three occupational groups. CONCLUSIONS: Our pilot results suggest that plasma concentrations of NTs, which are involved in various aspects of neuronal and cognitive functioning, may display significant differences among healthy individuals depending on their occupation. These observations warrant additional research to explore potential implications for the field of occupational medicine.

Where is your smartphone? An unusual mass within the tensor fasciae latae muscle.

We report a case of a 40-year-old Italian man presenting with an intramuscular schwannoma in his left thigh, which coincided with the area where he habitually stored his smartphone (front left trouser pocket). An ultrasound examination revealed a well-defined, encapsulated, hypoechoic lesion (41 × 15 × 28 mm) within the muscle, showing multiple small foci of vascularity on color Doppler. Elastographic analysis indicated a deformability score of 2, with some areas of stiffness. Magnetic resonance imaging confirmed the presence of a spindle-shaped mass in the tensor fasciae latae muscle, with varying enhancement after contrast administration. Notably, the location of the intramuscular mass closely corresponded to the placement of the phone's SIM card. While we cannot establish a definitive causal relationship between the patient's smartphone storage habit and the development of the intramuscular schwannoma, we speculate that the habitual storage location may have potentially acted as a risk or predisposing factor. This case underscores the need for further research on the potential health risks associated with smartphone storage habits, considering their widespread prevalence in today's society.

Exploring the Protective Efficacy of Topical Products for Actinic Keratosis Against Ultraviolet-Induced DNA and Protein Damage: An Experimental, Double-Blind Irradiation Study.

Introduction Numerous studies have delved into the clinical efficacy of different topical treatments for actinic keratosis (AK). However, our understanding remains limited regarding their capacity to prevent DNA and protein damage caused by ultraviolet radiation (UVR). Objectives The aim of this study was to analyze and compare the preventive capabilities of various AK-targeted products in countering DNA and protein alterations in human biopsies following exposure to experimental UVR. Methods Twelve healthy Caucasian volunteers (six men and six women) aged 18 years and above, with Fitzpatrick skin types II-III, participated in an experimental irradiation study. Six topical products, containing various ingredients (DNA repair enzymes, antioxidants, keratolytic agents, cyclooxygenase inhibitors, and/or sunscreens) were tested. The experimental sites were exposed to UVR at six times the minimal erythema dose for eight consecutive days. Each test product was applied 30 to 45 minutes before irradiation at a standard thickness of 2 mg/cm2. A control site was treated with the vehicle alone, serving as a negative control. The study focused on cyclobutane pyrimidine dimers (CPDs) and protein carbonylation (PC) as molecular markers of UVR-induced DNA and protein damage, respectively. Results The efficacy of different AK-targeted topical products showed substantial variation when applied to normal skin before experimental exposure to UVR. While sunscreens, predictably, played a crucial role, additional ingredients (i.e., DNA repair enzymes and antioxidants) also acted as vital protective agents for both the cellular genome and proteome, shielding them against UVR-induced damage. Conclusion In topical products specifically designed for AK, the strategic integration of DNA repair enzymes and antioxidants, in addition to sunscreens, establishes a critical defense mechanism against the detrimental effects of UVR on cellular DNA and proteins.

Mild Depressive Symptoms in Airline Pilots Associated With Impaired Executive Functions.

INTRODUCTION: While significant efforts have been made to understand the influence of depression-related impairments on executive functioning within the general population, the specific impact on airline pilots remains largely unexplored. Considering the crucial role that cognitive abilities play in the realm of aircraft piloting, it is imperative to probe into the potential repercussions of depressive symptoms on executive functions (EFs) among this professional cohort. OBJECTIVES:  This study aims to explore the associations between depressive symptoms and EFs in a convenience sample of airline pilots. METHODS:  Male airline pilots (n = 100) underwent the Beck Depression Inventory II (BDI-II) to gauge both the presence and intensity of depressive symptoms. The Stroop Color and Word Test (SCWT), the Digit Span Task (DST), and the Wisconsin Card Sorting Test (WCST) were used to assess EFs. RESULTS:  Of the entire sample of pilots, 88% (n = 88) demonstrated minimal depressive symptoms with a BDI-II score ranging from 0 to 13. The remaining 12% (n = 12) exhibited mild depression, with scores between 14 and 19. Pilots suffering from mild depression demonstrated prolonged color and word times and a higher time interference (TI) score on the SCWT. Moreover, these individuals exhibited lower scores on the DST across both the forward digit span (FDS) and backward digit span (BDS) subtests. Finally, the presence of mild depression correlated with an increased number of total errors, encompassing both perseverative and non-perseverative errors, in the WCST. After adjusting for potential confounding variables, we found an independent association between BDI-II scores and total errors in the WCST. CONCLUSION: Our research points to substantial differences in EFs between airline pilots demonstrating mild depression and those exhibiting minimal depressive symptoms. This information can catalyze heightened consciousness about the psychological welfare of pilots.

A Preliminary Study of Gut Microbiota in Airline Pilots: Comparison With Construction Workers and Fitness Instructors.

INTRODUCTION: The term "WORKbiota" has been used to describe the impact of occupational exposure and work types on human microbiota composition. Airline pilots, construction workers, and fitness instructors encompass three diverse professional groups, each with distinct work environments and lifestyle factors that may significantly influence their intestinal "WORKbiota." OBJECTIVES: The current preliminary investigation was aimed to compare the relative abundance of specific gut microbes among airline pilots, construction workers, and fitness instructors to shed light on any significant differences. By scrutinizing these diverse professional groups, our objective was to enhance our understanding of how occupational factors influence gut microbiota while identifying possible implications for occupational medicine. METHODS: A convenience sample consisting of 60 men representing three different professional domains - airline pilots, construction workers, and fitness instructors (with 20 individuals in each group) - was selected during regular outpatient occupational health consultations. The abundance of selected gut microbiota constituents, including Escherichia coli, Methanobrevibacter smithii, Akkermansia muciniphila, Faecalibacterium prausnitzii, Lactobacillus spp., Bifidobacterium spp., and Bacteroides spp., was quantified using quantitative SYBR Green quantitative real-time polymerase chain reaction (qRT-PCR) in stool samples. RESULTS: There were no significant variations among the groups concerning Escherichia coli, Methanobrevibacter smithii, Bifidobacterium spp., and Bacteroides spp. However, Lactobacillus spp. and Faecalibacterium prausnitzii were significantly more abundant in the microbiota of fitness instructors compared to both airline pilots and construction workers, with no significant differences observed between the latter two groups. Notably, the abundance of Akkermansia muciniphila demonstrated a progressive decline from fitness instructors to construction workers and ultimately to airline pilots, who exhibited the lowest levels. CONCLUSION: Airline pilots' gut microbiota was characterized by a lower abundance of health-promoting bacterial species, including Lactobacillus spp., Faecalibacterium prausnitzii, and Akkermansia muciniphila. Future research is essential to determine whether targeted interventions, such as probiotic and prebiotic supplementation, could potentially enhance gut microbiota composition and overall health in particular occupational groups.

Impact of different job types on serum cytokine levels in apparently healthy individuals: A comparative study among airline pilots, construction workers, and fitness instructors.

BACKGROUND: The impact of occupational factors on serum cytokine concentrations has not been extensively explored. In this preliminary investigation, we measured the amounts of 12 cytokines in the serum of healthy individuals, comparing three diverse professional categories (aviation pilots, building laborers, and exercise trainers) with distinct work settings and lifestyle factors. METHODS: The study sample comprised 60 men from three distinct professional fields - airline pilots, construction laborers, and fitness trainers (20 participants per category) - who were enlisted during regular outpatient occupational health appointments. Serum levels of interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p70, IL-17, tumor necrosis factor (TNF)-α, interferon (IFN)-α, and IFN-γ were measured on a Luminex® platform using a specific kit. Cytokine levels were compared among the three professional groups to determine any significant differences. RESULTS: Among the three occupational groups, fitness instructors demonstrated elevated IL-4 concentrations in comparison to both airline pilots and construction laborers, with no significant difference between the latter two professions. Additionally, a stepwise increase in IL-6 levels was identified, commencing with fitness instructors presenting the lowest quantities, succeeded by construction workers, and culminating with airline pilots, who displayed the most elevated concentrations. CONCLUSION: Serum cytokine levels in healthy individuals can exhibit variations based on their occupation. Given the unfavorable cytokine profile detected in airline pilots, it is crucial for the aviation sector to tackle potential health concerns within their employees.

Integrative metabolomics science in Alzheimer's disease: Relevance and future perspectives.

Alzheimer's disease (AD) is determined by various pathophysiological mechanisms starting 10-25 years before the onset of clinical symptoms. As multiple functionally interconnected molecular/cellular pathways appear disrupted in AD, the exploitation of high-throughput unbiased omics sciences is critical to elucidating the precise pathogenesis of AD. Among different omics, metabolomics is a fast-growing discipline allowing for the simultaneous detection and quantification of hundreds/thousands of perturbed metabolites in tissues or biofluids, reproducing the fluctuations of multiple networks affected by a disease. Here, we seek to critically depict the main metabolomics methodologies with the aim of identifying new potential AD biomarkers and further elucidating AD pathophysiological mechanisms. From a systems biology perspective, as metabolic alterations can occur before the development of clinical signs, metabolomics - coupled with existing accessible biomarkers used for AD screening and diagnosis - can support early disease diagnosis and help develop individualized treatment plans. Presently, the majority of metabolomic analyses emphasized that lipid metabolism is the most consistently altered pathway in AD pathogenesis. The possibility that metabolomics may reveal crucial steps in AD pathogenesis is undermined by the difficulty in discriminating between the causal or epiphenomenal or compensatory nature of metabolic findings.

Oxytocin as neuro-hormone and neuro-regulator exert neuroprotective properties: A mechanistic graphical review.

BACKGROUND: Neurodegeneration is progressive cell loss in specific neuronal populations, often resulting in clinical consequences with significant medical, societal, and economic implications. Because of its antioxidant, anti-inflammatory, and anti-apoptotic properties, oxytocin has been proposed as a potential neuroprotective and neurobehavioral therapeutic agent, including modulating mood disturbances and cognitive enchantment. METHODS: Literature searches were conducted using the following databases Web of Science, PubMed, Elsevier Science Direct, Google Scholar, the Core Collection, and Cochrane from January 2000 to February 2023 for articles dealing with oxytocin neuroprotective properties in preventing or treating neurodegenerative disorders and diseases with a focus on oxidative stress, inflammation, and apoptosis/cell death. RESULTS: The neuroprotective effects of oxytocin appears to be mediated by its anti-inflammatory properties, inhibition of neuro inflammation, activation of several antioxidant enzymes, inhibition of oxidative stress and free radical formation, activation of free radical scavengers, prevent of mitochondrial dysfunction, and inhibition of apoptosis. CONCLUSION: Oxytocin acts as a neuroprotective agent by preventing neuro-apoptosis, neuro-inflammation, and neuronal oxidative stress, and by restoring mitochondrial function.