The good and the bad of being connected: the integrons of aging

Hypothalamic circuits and aging: keeping the circadian clock updated

Over the past century, age-related diseases, such as cancer, type-2 diabetes, obesity, and mental illness, have shown a significant increase, negatively impacting overall quality of life. Studies on aged animal models have unveiled a progressive discoordination at multiple regulatory levels, including transcriptional, translational, and post-translational processes, resulting from cellular stress and circadian derangements. The circadian clock emerges as a key regulator, sustaining physiological homeostasis and promoting healthy aging through timely molecular coordination of pivotal cellular processes, such as stem-cell function, cellular stress responses, and inter-tissue communication, which become disrupted during aging. Given the crucial role of hypothalamic circuits in regulating organismal physiology, metabolic control, sleep homeostasis, and circadian rhythms, and their dependence on these processes, strategies aimed at enhancing hypothalamic and circadian function, including pharmacological and non-pharmacological approaches, offer systemic benefits for healthy aging. Intranasal brain-directed drug administration represents a promising avenue for effectively targeting specific brain regions, like the hypothalamus, while reducing side effects associated with systemic drug delivery, thereby presenting new therapeutic possibilities for diverse age-related conditions.

Aging and Autophagy: Roles in Musculoskeletal System Injury

Aging is a multifactorial process that ultimately leads to a decline in physiological function and a consequent reduction in the health span, and quality of life in elderly population. In musculoskeletal diseases, aging is often associated with a gradual loss of skeletal muscle mass and strength, resulting in reduced functional capacity and an increased risk of chronic metabolic diseases, leading to impaired function and increased mortality. Autophagy is a highly conserved physiological process by which cells, under the regulation of autophagy-related genes, degrade their own organelles and large molecules by lysosomal degradation. This process is unique to eukaryotic cells and is a strict regulator of homeostasis, the maintenance of energy and substance balance. Autophagy plays an important role in a wide range of physiological and pathological processes such as cell homeostasis, aging, immunity, tumorigenesis and neurodegenerative diseases. On the one hand, under mild stress conditions, autophagy mediates the restoration of homeostasis and proliferation, reduction of the rate of aging and delay of the aging process. On the other hand, under more intense stress conditions, an inadequate suppression of autophagy can lead to cellular aging. Conversely, autophagy activity decreases during aging. Due to the interrelationship between aging and autophagy, limited literature exists on this topic. Therefore, the objective of this review is to summarize the current concepts on aging and autophagy in the musculoskeletal system. The aim is to better understand the mechanisms of age-related changes in bone, joint and muscle, as well as the interaction relationship between autophagy and aging. Its goal is to provide a comprehensive perspective for the improvement of diseases of the musculoskeletal system.

The role of longevity-related genetic variant interactions as predictors of survival after 85 years of age

Genome-wide association studies and candidate gene studies have identified several genetic variants that might play a role in achieving longevity. This study investigates interactions between pairs of those single nucleotide polymorphisms (SNPs) and their effect on survival above the age of 85 in a sample of 327 Croatian individuals. Although none of the SNPs individually showed a significant effect on survival in this sample, 14 of the 359 interactions tested (between SNPs not in LD) reached the level of nominal significance (p<0.05), showing a potential effect on late-life survival. Notably, SH2B3 rs3184504 interacted with different SNPs near TERC, TP53 rs1042522 with different SNPs located near the CDKN2B gene, and CDKN2B rs1333049 with different SNPs in FOXO3, as well as with LINC02227 rs2149954. The other interaction pairs with a possible effect on survival were FOXO3 rs2802292 and ERCC2 rs50871, IL6 rs1800795 and GHRHR rs2267723, LINC02227 rs2149954 and PARK7 rs225119, as well as PARK7 rs225119 and PTPN1 rs6067484. These interactions remained significant when tested together with a set of health-related variables that also had a significant effect on survival above 85 years. In conclusion, our results confirm the central role of genetic regulation of insulin signalling and cell cycle control in longevity.

Relationship between aging and control of metabolic syndrome with telomere shortening: a cross-sectional study

Aging is considered one of the major risk factors for several human disorders. The telomere plays a crucial role in regulating cellular responsiveness to stress and growth stimuli as well as maintaining the integrity of the Deoxyribonucleic Acid (DNA), and aging leads to the progressive decline in the telomere length (TL) due to continuous cell division. The aim of this study was to determine the relationship between TL and advancing age and the impact of metabolic syndrome (MetS) on TL. Firstly, we determined the association of advancing age and TL, by measuring telomere length (T/S ratio) in healthy volunteers (n = 90). The TL was compared between normal population and patients with metabolic syndrome (n = 298). The age matched controlled and uncontrolled MetS patients (n = 149) were also compared for their TL T/S ratio. The TL showed negative correlation with advancing age, whereas the significant change was observed at the cut-offs of 40 and 70 years defining 40 with longer TL and 70 as shorter TL. The longest T/S ratio at 2.46 was measured at the age range of 1 year in healthy volunteers, while elderly population showed considerably shorter TL. The patients older than 60 years with poor or uncontrolled MetS had shorter TL, as compared to the controlled MetS. In conclusion our findings suggest that TL was negatively correlated with advancing age. Uncontrolled metabolic syndrome appeared to have worsening effects on TL. Telomere length appears to have potential to be used a parameter to determine age. However, further large scale studies are recommended to make firm guidelines.

Global analysis of aging-related protein structural changes uncovers enzyme-polymerization-based control of longevity

Aging is associated with progressive phenotypic changes. Virtually all cellular phenotypes are produced by proteins, and their structural alterations can lead to age-related diseases. However, we still lack comprehensive knowledge of proteins undergoing structural-functional changes during cellular aging and their contributions to age-related phenotypes. Here, we conducted proteome-wide analysis of early age-related protein structural changes in budding yeast using limited proteolysis-mass spectrometry (LiP-MS). The results, compiled in online ProtAge catalog, unraveled age-related functional changes in regulators of translation, protein folding, and amino acid metabolism. Mechanistically, we found that folded glutamate synthase Glt1 polymerizes into supramolecular self-assemblies during aging, causing breakdown of cellular amino acid homeostasis. Inhibiting Glt1 polymerization by mutating the polymerization interface restored amino acid levels in aged cells, attenuated mitochondrial dysfunction, and led to lifespan extension. Altogether, this comprehensive map of protein structural changes enables identifying mechanisms of age-related phenotypes and offers opportunities for their reversal.

Newly imported proteins in mitochondria are particularly sensitive to aggregation

AIM

A functional proteome is essential for life and maintained by protein quality control (PQC) systems in the cytosol and organelles. Protein aggregation is an indicator of a decline of PQC linked to aging and disease. Mitochondrial PQC is critical to maintain mitochondrial function and thus cellular fitness. How mitochondria handle aggregated proteins is not well understood. Here we tested how the metabolic status impacts on formation and clearance of aggregates within yeast mitochondria and assessed which proteins are particularly sensitive to denaturation.

METHODS

Confocal microscopy, electron microscopy, immunoblotting and genetics were applied to assess mitochondrial aggregate handling in response to heat shock and ethanol using the mitochondrial disaggregase Hsp78 as a marker for protein aggregates.

RESULTS

We show that aggregates formed upon heat or ethanol stress with different dynamics depending on the metabolic state. While fermenting cells displayed numerous small aggregates that coalesced into one large foci that was resistant to clearance, respiring cells showed less aggregates and cleared these aggregates more efficiently. Acute inhibition of mitochondrial translation had no effect, while preventing protein import into mitochondria by inhibition of cytosolic translation prevented aggregate formation.

CONCLUSION

Collectively, our data show that the metabolic state of the cells impacts the dynamics of aggregate formation and clearance, and that mainly newly imported and not yet assembled proteins are prone to form aggregates. Because mitochondrial functionality is crucial for cellular metabolism, these results highlight the importance of efficient protein biogenesis to maintain the mitochondrial proteome operational during metabolic adaptations and cellular stress.

Retinal Microvasculature and Neural Changes and Dietary Patterns in an Older Population in Southern Italy

BACKGROUND

Like other parts of the body, the retina and its neurovascular system are also affected by age-related changes. The rising age of populations worldwide makes it important to study the pathologies related to age and their potential risk factors, such as diet and eating habits. The aim of this study was to investigate the predictive power of food groups versus retinal features among noninstitutionalized older adults from Southern Italy using a machine learning approach.

METHODS

We recruited 530 subjects, with a mean age of 74 years, who were drawn from the large population of the Salus in Apulia Study. In the present cross-sectional study, eating habits were assessed with a validated food frequency questionnaire. For the visual assessment, a complete ophthalmic examination and optical coherence tomography-angiography analyses were performed.

RESULTS

The analyses identified 13 out of the 28 food groups as predictors of all our retinal variables: grains, legumes, olives-vegetable oil, fruiting vegetables, other vegetables, fruits, sweets, fish, dairy, low-fat dairy, red meat, white meat, and processed meat.

CONCLUSIONS

Eating habits and food consumption may be important risk factors for age-related retinal changes. A diet that provides the optimal intake of specific nutrients with antioxidant and anti-inflammatory powers, including carotenoids and omega-3 fatty acids, could have beneficial effects.

Interventions and management on multimorbidity: An overview of systematic reviews

BACKGROUND

Multimorbidity poses an immense burden on the healthcare systems globally, whereas the management strategies and guidelines for multimorbidity are poorly established. We aim to synthesize current evidence on interventions and management of multimorbidity.

METHODS

We searched four electronic databases (PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews). Systematic reviews (SRs) on interventions or management of multimorbidity were included and evaluated. The methodological quality of each SR was assessed by the AMSTAR-2 tool, and the quality of evidence on the effectiveness of interventions was assessed by the grading of recommendations assessment, development and evaluation (GRADE) system.

RESULTS

A total of 30 SRs (464 unique underlying studies) were included, including 20 SRs of interventions and 10 SRs summarizing evidence on management of multimorbidity. Four categories of interventions were identified: patient-level interventions, provider-level interventions, organization-level interventions, and combined interventions (combining the aforementioned two or three- level components). The outcomes were categorized into six types: physical conditions/outcomes, mental conditions/outcomes, psychosocial outcomes/general health, healthcare utilization and costs, patients' behaviors, and care process outcomes. Combined interventions (with patient-level and provider-level components) were more effective in promoting physical conditions/outcomes, while patient-level interventions were more effective in promoting mental conditions/outcomes and psychosocial outcomes/general health. As for healthcare utilization and care process outcomes, organization-level and combined interventions (with organization-level components) were more effective. The challenges in the management of multimorbidity at the patient, provider and organizational levels were also summarized.

CONCLUSION

Combined interventions for multimorbidity at different levels would be favored to promote different types of health outcomes. Challenges exist in the management at the patient, provider, and organization levels. Therefore, a holistic and integrated approach of patient-, provider- and organization- level interventions is required to address the challenges and optimize care of patients with multimorbidity.

Histone methyltransferase Smyd2 drives vascular aging by its enhancer-dependent activity

BACKGROUND

Vascular aging is one of the important factors contributing to the pathogenesis of cardiovascular diseases. However, the systematic epigenetic regulatory mechanisms during vascular aging are still unclear. Histone methyltransferase SET and MYND domain-containing protein 2 (Smyd2) is associated with multiple diseases including cancer and inflammatory diseases, but whether it is involved in endothelial cell senescence and aging-related cardiovascular diseases has not been directly proved. Thus, we aim to address the effects of Smyd2 on regulating angiotensin II (Ang II)-induced vascular endothelial cells (VECs) senescence and its epigenetic mechanism.

METHODS AND RESULTS

The regulatory role of Smyd2 in Ang II-induced VECs senescence was confirmed by performing loss and gain function assays. Chromatin immunoprecipitation-sequencing (ChIP-seq) analysis was used to systematically screen the potential enhancer during VECs senescence. Here, we found that Smyd2 was significantly upregulated in Ang II-triggered VECs, and deficiency of Smyd2 attenuated senescence-associated phenotypes both in vitro and in vivo. Mechanically, Ang II-induced upregulation of Smyd2 could increase the mono-methylation level of histone 3 lysine 4 (H3K4me1), resulting in a hyper-methylated chromatin state, then further activating enhancers adjacent to key aging-related genes, such as Cdkn1a and Cdkn2a, finally driving the development of vascular aging.

CONCLUSIONS

Collectively, our study uncovered that Smyd2 drives a hyper-methylated chromatin state via H3K4me1 and actives the enhancer elements adjacent to key senescence genes such as Cdkn1a and Cdkn2a, and further induces the senescence-related phenotypes. Targeting Smyd2 possibly unveiled a novel therapeutic candidate for vascular aging-related diseases.

DetecDiv, a generalist deep-learning platform for automated cell division tracking and survival analysis

Automating the extraction of meaningful temporal information from sequences of microscopy images represents a major challenge to characterize dynamical biological processes. So far, strong limitations in the ability to quantitatively analyze single-cell trajectories have prevented large-scale investigations to assess the dynamics of entry into replicative senescence in yeast. Here, we have developed DetecDiv, a microfluidic-based image acquisition platform combined with deep learning-based software for high-throughput single-cell division tracking. We show that DetecDiv can automatically reconstruct cellular replicative lifespans with high accuracy and performs similarly with various imaging platforms and geometries of microfluidic traps. In addition, this methodology provides comprehensive temporal cellular metrics using time-series classification and image semantic segmentation. Last, we show that this method can be further applied to automatically quantify the dynamics of cellular adaptation and real-time cell survival upon exposure to environmental stress. Hence, this methodology provides an all-in-one toolbox for high-throughput phenotyping for cell cycle, stress response, and replicative lifespan assays.

HSF-1: Guardian of the Proteome Through Integration of Longevity Signals to the Proteostatic Network

Discoveries made in the nematode Caenorhabditis elegans revealed that aging is under genetic control. Since these transformative initial studies, C. elegans has become a premier model system for aging research. Critically, the genes, pathways, and processes that have fundamental roles in organismal aging are deeply conserved throughout evolution. This conservation has led to a wealth of knowledge regarding both the processes that influence aging and the identification of molecular and cellular hallmarks that play a causative role in the physiological decline of organisms. One key feature of age-associated decline is the failure of mechanisms that maintain proper function of the proteome (proteostasis). Here we highlight components of the proteostatic network that act to maintain the proteome and how this network integrates into major longevity signaling pathways. We focus in depth on the heat shock transcription factor 1 (HSF1), the central regulator of gene expression for proteins that maintain the cytosolic and nuclear proteomes, and a key effector of longevity signals.

Long-Term Social Isolation-Induced Autophagy Inhibition and Cell Senescence Aggravate Cognitive Impairment in D(+)Galactose-Treated Male Mice

Aging is associated with physiological and pathological changes and presents health complications, such as dementia. Isolation has also been associated with the experience of growing old. Both have been linked individually to the incidence of cognitive decline. In this present study, the effects of these two phenomena have been looked at in animal models where aging was induced with D(+)Galactose in mice who underwent long-term post-weaned social isolation (L-PWSI). Assessing cognitive function using Y-maze, Morris water maze (MWM), and passive avoidance tests (PATs) confirmed that cognition is impaired in either of the treatments but worsened when the D(+)Galactose mice were subjected to L-PWSI. Moreover, a synaptic protein, PSD95, and dendritic spines density were significantly reduced in the L-PWSI and D(+)Galactose-treated mice. Our previous study revealed that autophagy deficit is involved in cognitive impairment in the L-PWSI model. Here, we first report the inhibited cell cycle in L-PWSI, combined with the decreased autophagy, aggravates cognitive impairment in D(+)Galactose-treated mice. Beyond these, the autophagy and cell cycle mechanisms that link isolation and aging have been explored. The close association between isolation and aging in humans is very real and needs much research attention going forward for possible therapeutic interventions.

Proteasome activity modulates amyloid toxicity

Alzheimer's disease (AD) is responsible for 60%-80% of identified cases of dementia. While the generation and accumulation of amyloid precursor protein (APP) fragments is accepted as a key step in AD pathogenesis, the precise role of these fragments remains poorly understood. To overcome this deficit, we induced the expression of the soluble C-terminal fragment of APP (C99), the rate-limiting peptide for the generation of amyloid fragments, in yeast that contain thermosensitive mutations in genes encoding proteasome subunits. Our previous work with this system demonstrated that these proteasome-deficient yeast cells, expressing C99 when proteasome activity was blunted, generated amyloid fragments similar to those observed in AD patients. We now report the phenotypic repercussions of inducing C99 expression in proteasome-deficient cells. We show increased levels of protein aggregates, cellular stress and chaperone expression, electron-dense accumulations in the nuclear envelope/ER, abnormal DNA condensation, and an induction of apoptosis. Taken together, these findings suggest that the generation of C99 and its associated fragments in yeast cells with compromised proteasomal activity results in phenotypes that may be relevant to the neuropathological processes observed in AD patients. These data also suggest that this yeast model should be useful for testing therapeutics that target AD-associated amyloid, since it allows for the assessment of the reversal of the perturbed cellular physiology observed when degradation pathways are dysfunctional.

Centenarian-Sourced Lactobacillus casei Combined with Dietary Fiber Complex Ameliorates Brain and Gut Function in Aged Mice

Dietary intervention could modulate age-related neurological disorders via the gut-brain axis. The potential roles of a probiotic and the dietary fiber complex (DFC) on brain and gut function in aged mice were investigated in this study. Lactobacillus casei LTL1361 and DFC were orally administrated for 12 weeks, and the learning and memory ability, as well as the oxidative parameters, inflammatory markers, gut barrier function and microbial metabolite short-chain fatty acids (SCFAs), were investigated. LTL1361 and DFC supplementation ameliorated cognitive ability, attenuated oxidative stress in brain and inflammation in serum and colon, ameliorated gut barrier function, and increased the SCFA concentrations and gene expression of SCFA receptors. The protective effect was more significantly enhanced in aged mice treated with the combination of LTL1361 and DFC than treated with LTL1361 or DFC alone. These results could be associated with the protected morphology of pyramidal nerve cells in hippocampus of mice brain and the downregulation of apoptosis marker caspase-3 in brain and upregulation of tight junction proteins in small intestine and colon. The results indicated that Lactobacillus casei LTL1361 and DFC alleviated age-related cognitive impairment, as well as protected brain and gut function. Lactobacillus casei LTL1361 and DFC might be used as novel and promising antiaging agents in human.

Clinical and Laboratory Characteristics of Elderly Patients with Pruritus

Introduction

For elderly, pruritus is considered the most common complaint in outpatient clinic. Pruritus occurs in association with primary skin disorders and can also be caused by many diseases and drugs. The aim of the work was to study clinical and laboratory characteristics of elderly patients with pruritus in Sohag, Egypt.

Patients and Methods

A cross-sectional study was conducted on 225 patients aged ≥60 years of both sexes complaining of pruritus and 160 age- and sex-matched patient group complaining of non-pruritic dermatological diseases. CBC, ESR, renal function tests, serology for HBV and HCV and blood glucose levels were done routinely in all patients (both groups). Skin biopsy was done in some selected cases.

Results

The mean duration of pruritus was 4.23 ± 4.9 months and was generalized in 73.8% of cases with moderate severity in 35.1% with winter exacerbation in 20%. Dermatological causes of pruritus were detected in 54.2%, followed by systemic causes in 29.8%. Eczema was the most common skin cause of senile itching in 33.7%, while renal diseases were the most common systemic cause in 46.2%.

Conclusion

Senile pruritus is a common problem in elderly. Early and proper management is mandatory to improve their quality of life.

Adipose-derived stem cells regulate metabolic homeostasis and delay aging by promoting mitophagy

Tissues undergo a process of degeneration as the body ages. Mesenchymal stem cells (MSCs) have been found to have major potential in delaying the aging process in tissues and organs. However, the mechanism underlying the anti-aging effects of MSC is not clear which limits clinical applications. In this study, we used adipose-derived mesenchymal stem cells (ADSCs) to perform anti-aging treatments on senescent cells and progeroid animal models. Following intervention with ADSCs, replicative senescence was delayed and metabolic homeostasis was transformed from catabolism to anabolism. Metabolomic tests were used to analyze different metabolites. We found that ADSCs acted to accelerate mitophagy which eliminated intracellular ROS and improved the quality of mitochondria. These processes acted to regulate the cellular metabolic homeostasis and ultimately delayed the process of aging. Allogeneic stem cell therapy in a Progeria animal model (DNA polymerase gamma (POLG) knockin, mitochondrial dysfunction) also showed that ADSC therapy can improve alopecia and kyphosis by promoting mitophagy. Our research confirms for the first time that allogeneic stem cell therapy can improve aging-related symbols and phenotypes through mitochondrial quality control. These results are highly significant for the future applications of stem cells in aging-related diseases.

Cell nonautonomous roles of NHR-49 in promoting longevity and innate immunity

Aging and immunity are inextricably linked and many genes that extend life span also enhance immunoresistance. However, it remains unclear whether longevity-enhancing factors modulate immunity and longevity by discrete or shared mechanisms. Here, we demonstrate that the Caenorhabditis elegans pro-longevity factor, NHR-49, also promotes resistance against Pseudomonas aeruginosa but modulates immunity and longevity distinctly. NHR-49 expression increases upon germline ablation, an intervention that extends life span, but was lowered by Pseudomonas infection. The immunosusceptibility induced by nhr-49 loss of function was rescued by neuronal NHR-49 alone, whereas the longevity diminution was rescued by expression in multiple somatic tissues. The well-established NHR-49 target genes, acs-2 and fmo-2, were also differentially regulated following germline elimination or Pseudomonas exposure. Interestingly, neither gene conferred immunity toward Gram-negative Pseudomonas, unlike their known functions against gram-positive pathogens. Instead, genes encoding antimicrobial factors and xenobiotic-response proteins upregulated by NHR-49 contributed to resistance against Pseudomonas. Thus, NHR-49 is differentially regulated by interventions that bring about long-term changes (life span extension) versus short-term stress (pathogen exposure) and in response it orchestrates discrete outputs, including pathogen-specific transcriptional programs.

Gut Microbiota: Critical Controller and Intervention Target in Brain Aging and Cognitive Impairment

The current trend for the rapid growth of the global aging population poses substantial challenges for society. The human aging process has been demonstrated to be closely associated with changes in gut microbiota composition, diversity, and functional features. During the first 2 years of life, the gut microbiota undergoes dramatic changes in composition and metabolic functions as it colonizes and develops in the body. Although the gut microbiota is nearly established by the age of three, it continues to mature until adulthood, when it comprises more stable and diverse microbial species. Meanwhile, as the physiological functions of the human body deteriorated with age, which may be a result of immunosenescence and "inflammaging," the guts of elderly people are generally characterized by an enrichment of pro-inflammatory microbes and a reduced abundance of beneficial species. The gut microbiota affects the development of the brain through a bidirectional communication system, called the brain-gut-microbiota (BGM) axis, and dysregulation of this communication is pivotal in aging-related cognitive impairment. Microbiota-targeted dietary interventions and the intake of probiotics/prebiotics can increase the abundance of beneficial species, boost host immunity, and prevent gut-related diseases. This review summarizes the age-related changes in the human gut microbiota based on recent research developments. Understanding these changes will likely facilitate the design of novel therapeutic strategies to achieve healthy aging.

Different Parts of the Chicken Embryo Egg Improve D-Galactose-Induced Aging in a Mice Model

Chick (CE) or duck embryo eggs are known for nutritional supplement foods in traditional East countries for physical fitness enhancement and postpartum conditioning for many years. In this study, we evaluated the effects of different parts of the 10-day CE (embryo: CEr, yolk: CEw, and chorioallantoic membrane: CEp) on the antifatigue and antiaging activities in a D-galactose- (D-gal) induced aging mice model. The results showed CEp obviously increased the muscle weight and the liver and muscle glycogen content and enhanced exercise performance. In the antiaging assay, CEp significantly increased the activity of superoxide dismutase (SOD) and Glutathione Peroxidase (GPx). Moreover, the immunohistochemistry results of NRF-2 and HO-1 were also detected in the livers of mice in the D-gal/CEp group. The only partially potential such as CEr might improve OFT function with TG level, and CEw had strange grip strength. Therefore, we suggest that CEp has a potent antifatigue ability and could minimize the occurrence of age-associated disorders, more than other parts of the 10 days chicken embryo egg.

Short-term protein restriction at advanced age stimulates FGF21 signalling, energy expenditure and browning of white adipose tissue

Dietary protein restriction has been demonstrated to improve metabolic health under various conditions. However, the relevance of ageing and age-related decline in metabolic flexibility on the effects of dietary protein restriction has not been addressed. Therefore, we investigated the effect of short-term dietary protein restriction on metabolic health in young and aged mice. Young adult (3 months old) and aged (18 months old) C57Bl/6J mice were subjected to a 3-month dietary protein restriction. Outcome parameters included fibroblast growth factor 21 (FGF21) levels, muscle strength, glucose tolerance, energy expenditure (EE) and transcriptomics of brown and white adipose tissue (WAT). Here, we report that a low-protein diet had beneficial effects in aged mice by reducing some aspects of age-related metabolic decline. These effects were characterized by increased plasma levels of FGF21, browning of subcutaneous WAT, increased body temperature and EE, while no changes were observed in glucose homeostasis and insulin sensitivity. Moreover, the low-protein diet used in this study was well-tolerated in aged mice indicated by the absence of adverse effects on body weight, locomotor activity and muscle performance. In conclusion, our study demonstrates that a short-term reduction in dietary protein intake can impact age-related metabolic health alongside increased FGF21 signalling, without negatively affecting muscle function. These findings highlight the potential of protein restriction as a strategy to induce EE and browning of WAT in aged individuals.

Telomere length assessment in blood leukocytes of patients with sarcoidosis

BACKGROUND

Accelerated aging and telomere shortening have been studied in many chronic diseases such as interstitial pulmonary fibrosis and chronic obstructive pulmonary disease. Different studies have shown that patients with these diseases have shorter telomere lengths than controls; this can be a marker of the progression and outcome of the disease. So far, a few studies have been evaluated the telomere length in sarcoidosis. In this study we determine the telomere length in patients with sarcoidosis and compare it with control subjects.

OBJECTIVE

Our aim is to compare telomere length in patients with sarcoidosis and normal population. Methods: We select 58 patients with sarcoidosis who were visited in the sarcoidosis clinic of Masih Daneshvari Hospital. 58 sex and age-matched (with±2 years) healthy control subjects were selected. Telomere length was measured by quantitative real time PCR as described by Cawthon on peripheral blood sample. The telomere repeat copy number (T) to single-gene copy number(S) ratio was calculated using the comparative Ct method. Results: The mean and standard deviation of telomere length in the patient and control group was 0.65 ± 0.05 and 0.72 ± 0.07 respectively. There was a statistically significant difference between the two groups. (P = 0.031). Conclusion: Sarcoidosis is an inflammatory disease that can involve many organs. Like other chronic diseases, aging phenomenon occurs in that; which led to decrease cellular and tissue telomere length. This article demonstrates shorter telomere length in Iranian sarcoidosis patients compared to normal population.

Senescence-Associated Secretory Phenotype Suppression Mediated by Small-Sized Mesenchymal Stem Cells Delays Cellular Senescence through TLR2 and TLR5 Signaling

In order to provide a sufficient number of cells for clinical use, mesenchymal stem cells (MSCs) must be cultured for long-term expansion, which inevitably triggers cellular senescence. Although the small size of MSCs is known as a critical determinant of their fate, the main regulators of stem cell senescence and the underlying signaling have not been addressed. Umbilical cord blood-derived MSCs (UCB-MSCs) were obtained using size-isolation methods and then cultured with control or small cells to investigate the major factors that modulate MSC senescence. Cytokine array data suggested that the secretion of interukin-8 (IL-8) or growth-regulated oncogene-alpha (GROa) by senescent cells was markedly inhibited during incubation of small cells along with suppression of cognate receptor (C-X-C motif chemokine receptor2, CXCR2) via blockade of the autocrine/paracrine positive loop. Moreover, signaling via toll-like receptor 2 (TLR2) and TLR5, both pattern recognition receptors, drove cellular senescence of MSCs, but was inhibited in small cells. The activation of TLRs (2 and 5) through ligand treatment induced a senescent phenotype in small cells. Collectively, our data suggest that small cell from UCB-MSCs exhibit delayed cellular senescence by inhibiting the process of TLR signaling-mediated senescence-associated secretory phenotype (SASP) activation.

Aging Regulated Through a Stability Model of Insulin/Insulin Growth Factor Receptor Function

Mutations of the insulin-like receptor in Drosophila extend lifespan. New research suggests this receptor operates in two modes. The first extends lifespan while slowing reproduction and reducing growth. The second strongly extends lifespan without impairing growth or reproduction; it confers longevity assurance. The mutation that confers longevity assurance resides in the kinase insert domain, which contains a potential SH2 binding site for substrate proteins. We apply a recent model for the function of receptor tyrosine kinases to propose how insulin receptor structure can modulate aging. This concept hypothesizes that strong insulin-like ligands promote phosphorylation of high threshold substrate binding sites to robustly induce reproduction, which impairs survival as a consequence of trade-offs. Lower levels of receptor stimulation provide less kinase dimer stability, which reduces reproduction and extends lifespan by avoiding reproductive costs. Environmental conditions that favor diapause alter the expression of insulin ligands to further repress the stability of the interacting kinase domains, block phosphorylation of low threshold substrates and thus induce a unique molecular program that confers longevity assurance. Mutations of the insulin receptor that block low-phosphorylation site interactions, such as within the kinase insert domain, can extend lifespan while maintaining overall dimer stability. These flies are long-lived while maintaining reproduction and growth. The kinase insert domain of Drosophila provides a novel avenue from which to seek signaling of the insulin/insulin-like growth factor system of humans that modulate aging without impacting reproduction and growth, or incurring insulin resistance pathology.

PPARγ agonists delay age-associated metabolic disease and extend longevity

Aging leads to a number of disorders caused by cellular senescence, tissue damage, and organ dysfunction. It has been reported that anti‐inflammatory and insulin‐sensitizing compounds delay, or reverse, the aging process and prevent metabolic disorders, neurodegenerative disease, and muscle atrophy, improving healthspan and extending lifespan. Here we investigated the effects of PPARγ agonists in preventing aging and increasing longevity, given their known properties in lowering inflammation and decreasing glycemia. Our molecular and physiological studies show that long‐term treatment of mice at 14 months of age with low doses of the PPARγ ligand rosiglitazone (Rosi) improved glucose metabolism and mitochondrial functionality. These effects were associated with decreased inflammation and reduced tissue atrophy, improved cognitive function, and diminished anxiety‐ and depression‐like conditions, without any adverse effects on cardiac and skeletal functionality. Furthermore, Rosi treatment of mice started when they were 14 months old was associated with lifespan extension. A retrospective analysis of the effects of the PPARγ agonist pioglitazone (Pio) on longevity showed decreased mortality in patients receiving Pio compared to those receiving a PPARγ‐independent insulin secretagogue glimepiride. Taken together, these data suggest the possibility of using PPARγ agonists to promote healthy aging and extend lifespan.

Peroxiredoxin promotes longevity and H2O2-resistance in yeast through redox-modulation of protein kinase A

Peroxiredoxins are H2O2 scavenging enzymes that also carry out H2O2 signaling and chaperone functions. In yeast, the major cytosolic peroxiredoxin, Tsa1 is required for both promoting resistance to H2O2 and extending lifespan upon caloric restriction. We show here that Tsa1 effects both these functions not by scavenging H2O2, but by repressing the nutrient signaling Ras-cAMP-PKA pathway at the level of the protein kinase A (PKA) enzyme. Tsa1 stimulates sulfenylation of cysteines in the PKA catalytic subunit by H2O2 and a significant proportion of the catalytic subunits are glutathionylated on two cysteine residues. Redox modification of the conserved Cys243 inhibits the phosphorylation of a conserved Thr241 in the kinase activation loop and enzyme activity, and preventing Thr241 phosphorylation can overcome the H2O2 sensitivity of Tsa1-deficient cells. Results support a model of aging where nutrient signaling pathways constitute hubs integrating information from multiple aging-related conduits, including a peroxiredoxin-dependent response to H2O2.

Polyesterified Sesquiterpenoids from the Seeds of Celastrus paniculatus as Lifespan-Extending Agents for the Nematode Caenorhabditis elegans

Eighteen new polyesterified dihydro-β-agarofurans, celaspaculins A-R, as well as 11 known ones, were purified from the seeds of Celastrus paniculatus. The structures of new isolates were identified by extensive spectroscopic analysis and X-ray diffraction studies. The lifespan-extending activity of the dihydro-β-agarofuran-enriched fraction and 10 abundant polyesterified dihydro-β-agarofurans was evaluated on the nematode Caenorhabditis elegans model. Consequently, the dihydro-β-agarofuran-enriched fraction and compounds 5, 14, and 21 notably increased the average survival time of C. elegans by 23%, 16%, 18%, and 17%, respectively, compared with the blank control group (p < 0.0001).

The antidiabetic and hepatoprotective effects of myricitrin on aged mice with D-galactose

AIM

The present study aims to evaluate the effects of antidiabetic and hepatoprotective of myricitrin in the aged mice induced by D-galactose (D-gal).

BACKGROUND

Aging occurs during a person's life; there has been no way to stop the aging process, but antioxidant and changing lifestyles can delay it.

METHODS

In this experimental study, 72 female adult mice (weighing30-35g) were randomly divided into six groups: 1: control, 2: D-gal at 500mg/kg/d, 3-5: D-gal+ Myricitrin at 5, 10 and 20mg/kg/d 6: D-gal+ Vitamin E at 100mg/kg/d. Aging induced by D-gal for 45 days via intraperitoneal. Myricitrin and Vitamin E administrated orally by gavage for the last 28 days. The blood glucose, insulin level, β-cell function, insulin resistance, hepatic enzymes, lipid profile, and histology of the liver, and pancreas were evaluated.

RESULTS

D-gal injection increased the glucose (p<0.001) and insulin levels (p<0.01) compared to control group. Myricitrin (p<0.01) and Vitamin E (p<0.001) increased insulin and decreased blood glucose levels compared to D-gal group. Myricitrin had a similar impact on insulin levels to vitamin E. Insulin resistance induced in the D-gal group (p<0.001). Myricitrin reduced insulin resistance and increased β-cell function (p<0.01) compared to D-gal group. D-gal elevated (p<0.01) cholesterol, LDL and triglyceride level, myricitrin (p<0.001), and Vitamin E (p<0.05) were reduced.

CONCLUSION

D-gal-induced aging causes the accumulation of RBCs, inflammation in the liver, and changes in the number and diameter of Langerhans islets in the pancreas. Myricitrin improved these D-gal effects. Myricitrin had the anti-diabetic and hepatoprotective effects on the aged mice induced by D-galactose.

RNA-seq profiling, and impaired autophagic process in skeletal muscle of MELAS

Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes (MELAS) is a common subtype of mitochondrial disease with high disability and mortality rate. The molecular mechanisms of MELAS are largely unknown and whether autophagy is activated in this disease remains controversial. In this work, we reported whole transcriptome profiling of skeletal muscle of MELAS patients and age-matched controls. Analyses revealed that MELAS patients had 224 differentially expressed genes (174 down-regulated, 50 up-regulated) compared to age-matched controls. Most of these genes relevant to MELAS are involved in signal transduction, metabolic process and immune system process. However, the RNA-seq data indicated that autophagy was not altered in MELAS. Functional assays showed that increased reactive oxygen species (ROS), decreased ATP production and decreased lysosome content in fibroblasts derived from MELAS patients, suggesting that mitochondrial dysfunction and degradation deficiency in MELAS. Furthermore, Western-blot analyses using skeletal muscle and fibroblasts derived from MELAS patients showed that autophagy was impaired in MEALS since two important autophagic genes: Beclin-1 and LC3-II, were significantly down-regulated. In conclusion, our study identified molecules and pathways involved in the mechanisms of MELAS, and the impairment of autophagy in this disease, which may serve as the potential therapeutic target for MELAS.

Effect of the Resveratrol Rice DJ526 on Longevity

Resveratrol is the best-known chemical for extending the lifespan of various organisms. Extensive recent research has shown that resveratrol can extend the lifespan of single-celled organisms, but its effects on the extension of animal lifespans are marginal. Despite the limited efficacy of pure resveratrol, resveratrol with the endogenous property of the DJ rice in the resveratrol rice DJ526 previously showed profound health benefits. Here, we report that the resveratrol rice DJ526 markedly extended the lifespan of the fruit fly Drosophila melanogaster by as much as 41.4% compared to that of the control. The resveratrol rice DJ526 also improved age-related symptoms such as locomotive deterioration, body weight gain, eye degeneration and neurodegeneration in D. melanogaster upon aging. This result shows the most significantly improved lifespan in animal experiments to date, meaning that the resveratrol rice DJ526 will assist in the development of a therapeutic agent for longevity or addressing age-related degeneration.

Vitamin C restores ovarian follicular reservation in a mouse model of aging

Ovarian aging is related to the reduction of oocyte quality and ovarian follicles reservation leading to infertility. Vitamin C is a natural antioxidant which may counteract with adverse effects of aging in the ovary. The aim of this study was to evaluate the possible effect of vitamin C on NMRI mice ovarian aging according to the stereological study. In this experimental study, 36 adult female mice (25-30 g) were divided into two groups: control and vitamin C. Vitamin C (150 mg/kg/day) were administered by oral gavage for 33 weeks. Six animals of each group were sacrificed on week 8, 12, and 33, and right ovary samples were extracted for stereology analysis. Our data showed that the total volume of ovary, cortex, medulla and corpus luteum were significantly increased in vitamin C group in comparison to the control groups (P≤0.05). In addition, the total number of primordial, primary, secondary, and antral follicles as well as granulosa cells were improved in vitamin C group in compared to the control groups (P≤0.05). No significant difference was observed in total volume of oocytes in antral follicles between control and vitamin C groups. Our data showed that vitamin C could notably compensate undesirable effects of ovarian aging in a mouse model.

Stem Cell-Derived Exosomes Prevent Aging-Induced Cardiac Dysfunction through a Novel Exosome/lncRNA MALAT1/NF-κB/TNF-α Signaling Pathway

Aging is a risk factor for cardiovascular disease, and there is no effective therapeutic approach to alleviate this condition. NF-κB and TNF-α have been implicated in the activation of the aging process, but the signaling molecules responsible for the inactivation of NF-κB and TNF-α remain unknown. Exosomes have been reported to improve heart functions by releasing miRNA. Recent studies suggest that lncRNAs are more tissue-specific and developmental stage-specific compared to miRNA. However, the role of lncRNA in exosome-mediated cardiac repair has not been explored. In the present study, we focused on metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), which is an lncRNA associated with cell senescence. We discovered that human umbilical cord mesenchymal stem cell- (UMSC-) derived exosomes prevent aging-induced cardiac dysfunction. Silencer RNA against lncRNA MALAT1 blocked the beneficial effects of exosomes. In summary, we discovered that UMSC-derived exosomes prevent aging-induced cardiac dysfunction by releasing novel lncRNA MALAT1, which in turn inhibits the NF-κB/TNF-α signaling pathway. These findings will lead to the development of therapies that delay aging and progression of age-related diseases.

Linking cellular proteostasis to yeast longevity

Proteostasis is a cellular housekeeping process that refers to the healthy maintenance of the cellular proteome that governs the fate of proteins from synthesis to degradation. Perturbations of proteostasis might result in protein dysfunction with consequent deleterious effects that can culminate in cell death. To deal with the loss of proteostasis, cells are supplied with a highly sophisticated and interconnected network that integrates as major players the molecular chaperones and the protein degradation pathways. It is well recognized that the ability of cells to maintain proteostasis declines during ageing, although the precise mechanisms are still elusive. Indeed, genetic or pharmacological enhancement of the proteostasis network has been shown to extend lifespan in a variety of ageing models. Therefore, an improved understanding of the interventions/mechanisms that contribute to cellular protein quality control will have a huge impact on the ageing field. This mini-review centers on the current knowledge about the major pathways that contribute for the maintenance of Saccharomyces cerevisiae proteostasis, with particular emphasis on the developments that highlight the multidimensional nature of the proteostasis network in the maintenance of proteostasis, as well as the age-dependent changes on this network.

Improving effect of a probiotic mixture on memory and learning abilities in d-galactose-treated aging mice

The aim of this study was to evaluate the antiaging effect of a probiotic mixture using an in vivo mouse model in which aging was induced with d-galactose. Results of the Morris water maze test indicated that long-term administration of the probiotic mixture improved memory and learning abilities and ameliorated the apoptosis pattern in the hippocampus of aging mice treated with d-galactose. An antioxidation experiment indicated that administration of the probiotic mixture could restore activities of the antioxidant enzymes superoxide dismutase and catalase and inhibit the production of malondialdehyde. The antioxidant-related proteins nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were upregulated in liver after treatment of d-galactose-treated aging mice with probiotics. Finally, the probiotic treatment did affect the production of short-chain fatty acids in d-galactose-treated aging mice. Our results highlighted a possible antioxidative effect triggered by short-chain fatty acids that contributed to improving the memory and learning abilities following treatment with the probiotic mixture and suggested that probiotics could serve as a therapy to modulate physiological function.

FUS interacts with ATP synthase beta subunit and induces mitochondrial unfolded protein response in cellular and animal models

FUS (fused in sarcoma) proteinopathy is a group of neurodegenerative diseases characterized by the formation of inclusion bodies containing the FUS protein, including frontotemporal lobar degeneration and amyotrophic lateral sclerosis. Previous studies show that mitochondrial damage is an important aspect of FUS proteinopathy. However, the molecular mechanisms by which FUS induces mitochondrial damage remain to be elucidated. Our biochemical and genetic experiments demonstrate that FUS interacts with the catalytic subunit of mitochondrial ATP synthase (ATP5B), disrupts the formation of ATP synthase complexes, and inhibits mitochondrial ATP synthesis. FUS expression activates the mitochondrial unfolded protein response (UPR^mt). Importantly, down-regulating expression of ATP5B or UPR^mt genes in FUS transgenic flies ameliorates neurodegenerative phenotypes. Our data show that mitochondrial impairment is a critical early event in FUS proteinopathy, and provide insights into the pathogenic mechanism of FUS-induced neurodegeneration.

Recreational soccer as sport medicine for middle-aged and older adults: a systematic review

Background

Strategies to prevent or attenuate the age-related decline in physical and physiological function and reduce chronic disease risk factors are of clinical importance.

Objective

To examine the health benefits of recreational soccer in middle-aged and older adults.

Design

Systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Data sources

All available records up until 9 June 2017 in PubMed, Web of Science, SPORTDiscus, MEDLINE, Embase, CINAHL Plus, PsycINFO and Cochrane Library databases.

Eligibility criteria for selecting studies

All randomised trials with or without a control group (randomised controlled trials or randomised uncontrolled trials) and non-randomised controlled trials that used recreational soccer, which includes small-sided soccer games, as the sole or principal intervention, and reported relevant effects in untrained/sedentary, healthy or unhealthy adults aged 40 years and above were included.

Results

Five trials described in 13 articles were included, which scored 6–9 out of 12 points on the modified Delphi quality rating scale. The duration was from 12 to 52 weeks, with various frequencies, volumes and game formats performed both outdoors and indoors with men and women. The trials indicate that recreational soccer may result in improvement in cardiovascular function, body composition and functional ability, although no significant changes were observed in postural balance.

Conclusion

Recreational soccer should be considered an alternative exercise modality for untrained, healthy or unhealthy middle-aged and older adults of both sexes to maintain an active lifestyle and mitigate a wide array of physical and physiological age-related changes.

Evidence of Rentian Scaling of Functional Modules in Diverse Biological Networks

Biological networks have long been known to be modular, containing sets of nodes that are highly connected internally. Less emphasis, however, has been placed on understanding how intermodule connections are distributed within a network. Here, we borrow ideas from engineered circuit design and study Rentian scaling, which states that the number of external connections between nodes in different modules is related to the number of nodes inside the modules by a power-law relationship. We tested this property in a broad class of molecular networks, including protein interaction networks for six species and gene regulatory networks for 41 human and 25 mouse cell types. Using evolutionarily defined modules corresponding to known biological processes in the cell, we found that all networks displayed Rentian scaling with a broad range of exponents. We also found evidence for Rentian scaling in functional modules in the Caenorhabditis elegans neural network, but, interestingly, not in three different social networks, suggesting that this property does not inevitably emerge. To understand how such scaling may have arisen evolutionarily, we derived a new graph model that can generate Rentian networks given a target Rent exponent and a module decomposition as inputs. Overall, our work uncovers a new principle shared by engineered circuits and biological networks.

Origination, change, and modulation of geriatric disease-related gut microbiota during life

The age-related changes in the diversity and composition of the gut microbiota are well described in recent studies. These changes have been suggested to be influenced by age-associated weakening of the immune system and low-grade chronic inflammation, resulting in numerous age-associated pathological conditions. Gut microbiota homeostasis is important throughout the life of the host by providing vital functions to regulate various immunological functions and homeostasis. Based on published results, we summarize the relationship between the gut microbiota and aging-related diseases, especially Parkinson's disease, immunosenescence, rheumatoid arthritis, bone loss, and metabolic syndrome. The change in composition of the gut microbiota and gut ecosystem during life and its influence on the host immunologic and metabolic phenotype are also analyzed to determine factors that affect aging-related diseases. Approaches to maintain host health and prevent or cure geriatric diseases are also discussed.

The African turquoise killifish: A research organism to study vertebrate aging and diapause

The African turquoise killifish has recently gained significant traction as a new research organism in the aging field. Our understanding of aging has strongly benefited from canonical research organisms—yeast, C. elegans, Drosophila, zebrafish, and mice. Many characteristics that are essential to understand aging—for example, the adaptive immune system or the hypothalamo‐pituitary axis—are only present in vertebrates (zebrafish and mice). However, zebrafish and mice live more than 3 years and their relatively long lifespans are not compatible with high‐throughput studies. Therefore, the turquoise killifish, a vertebrate with a naturally compressed lifespan of only 4–6 months, fills an essential gap to understand aging. With a recently developed genomic and genetic toolkit, the turquoise killifish not only provides practical advantages for lifespan and longitudinal experiments, but also allows more systematic characterizations of the interplay between genetics and environment during vertebrate aging. Interestingly, the turquoise killifish can also enter a long‐term dormant state during development called diapause. Killifish embryos in diapause already have some organs and tissues, and they can last in this state for years, exhibiting exceptional resistance to stress and to damages due to the passage of time. Understanding the diapause state could give new insights into strategies to prevent the damage caused by aging and to better preserve organs, tissues, and cells. Thus, the African turquoise killifish brings two interesting aspects to the aging field—a compressed lifespan and a long‐term resistant diapause state, both of which should spark new discoveries in the field.

Antioxidant effects of compound walnut oil capsule in mice aging model induced by D-galactose

Background

Many plant original foods have been shown beneficial effects in humans. In the previous work, we have developed a compound capsule which contains major constituents of walnut oil and grape seed extract.

Objective

To investigate the antioxidant effects of the Compound Walnut Oil Capsule (WOC) in aging model induced by D-gal.

Design

70 C57BL/6J mice were randomly divided into seven groups. Mice in normal group received daily subcutaneous injection of saline while the control group, WOC groups, Vitamin C (VC) group and pure walnut oil group received daily subcutaneous injection of D-galactose (D-gal) for 8 weeks. Total antioxidant capacity (T-AOC), super dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) in serum, liver and brain were determined. The expression of Heme Oxygenase (HO-1), iNOS and Klotho in liver and brain were obtained.

Results

WOC could improve the pathologic lesions caused by oxidative stress and significantly enhance the T-AOC, increase the activities of SOD, GSH-Px and decrease the contents of MDA in serum, liver and brain. Also, the WOC could obviously up-regulate the expression of HO-1 and Klotho and down-regulate the expression of iNOS.

Conclusion

WOC can be used as an anti-aging food for its effectively eliminating free radicals, enhancing the antioxidant capacity and alleviating the damages of oxidative stress.

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.

A Futile Battle? Protein Quality Control and the Stress of Aging

There exists a phenomenon in aging research whereby early life stress can have positive impacts on longevity. The mechanisms underlying these observations suggest a robust, long-lasting induction of cellular defense mechanisms. These include the various unfolded protein responses of the endoplasmic reticulum (ER), cytosol, and mitochondria. Indeed, ectopic induction of these pathways, in the absence of stress, is sufficient to increase lifespan in organisms as diverse as yeast, worms, and flies. Here, we provide an overview of the protein quality control mechanisms that operate in the cytosol, mitochondria, and ER and discuss how they affect cellular health and viability during stress and aging.

Aging-related SUMOylation pattern in the cortex and blood plasma of wild type mice

Protein activities and mechanisms related to aging has become a growing interest nowadays. Since SUMOylation is implicated in several cellular processes, its investigation related to senescence, aging and frailty is of high interest. In our study, wild type mice cortical lysates, synaptosomes and plasma have been processed to evaluate SUMOylation and SUMO machinery expression (Ubc9 and SENP1 enzymes) profile at different ages. In cortical lysates, SUMO-1ylation reached a peak at 6 months followed by a decrease; while in synaptosomes, it progressively increased till 18 months. Regarding SUMO-2/3ylation, it was observed a similar trend in both lysate and synaptosomes where the protein conjugation was the highest at 6 months but interestingly decreased afterwards. In addition, Ubc9 and SENP1 enzymes showed a linear increased expression level in both brain preparations. Since SUMOylation process is ubiquitously expressed, we were interested to identify SUMO conjugation at peripheral level too. Thus, SUMO-1ylation and SUMO-2/3ylation expression level has been detected in mouse plasma that revealed an inverted U-shaped curve trend during mice lifespan. Surprisingly, SENP1 enzyme was not present in the plasma while Ubc9 enzyme reached a plateau at 6 months and was highly expressed till 18 months. In conclusion, our data indicates that SUMOylation is highly correlated with age-related processes which indisputably need to be considered for further investigation.

Isolation of Distinct Types of Neurons from Fresh Brain Tissue Using Laser Microdissection in Combination with High-Performance Liquid Chromatography-Mass Spectrometry

Humans age and the ageing process affects cells in all areas of the human body, including nerve cells within the brain. With advancing age there is also a rise in the probability of developing a neurodegenerative disorder such as, e.g., amyotrophic lateral sclerosis, Huntington's disease, Parkinson's disease, or Alzheimer's disease. In all these age-related neurodegenerative disorders, distinct neuron populations within specific brain regions are primarily affected. For example, Parkinson's disease is characterized by a slowly progressive degeneration of dopaminergic neurons in the substantia nigra whereas the entorhinal cortex is first affected in Alzheimer's disease. In patients suffering from Huntington's disease, neurons in both striatum and cortex undergo substantial cell loss and in amyotrophic lateral sclerosis the neurodegeneration arises from the spinal cord and the motor cortex. For the investigation of the differences in neuronal vulnerability, it is important to examine the protein expression pattern in these specific neural populations. By this, conclusions about the origination process of these diseases can be achieved. In order to obtain this objective, specific isolation of distinct neurons from the surrounding brain tissue is indispensable. However, discrimination as well as isolation of distinct types of neurons can be challenging, due to the brain tissue's complexity. With traditional methods such as the homogenization of tissue samples, a specific isolation of single neuron populations is not feasible because homogenization results into a mixture containing all cell types. Laser microdissection can overcome this technical limitation. First, this method enables visualization of tissues via a microscopic unit and therefore an enhanced discrimination of different brain cells. Second, a laser device guarantees a contact-free and consequently a contamination-free separation of distinct neurons from the surrounding brain tissue. In the following, we present a detailed protocol that includes a workflow for the isolation and analysis of neurons from freshly frozen post mortem human brain tissue samples. During this procedure, the brain tissue is sectioned, stained, laser microdissected, and ultimately analyzed by high-performance liquid chromatography-mass spectrometry.

Reinforcing mitochondrial functions in aging brain: An insight into Parkinson's disease therapeutics

Mitochondria, the powerhouse of the neural cells in the brain, are also the seat of certain essential gene signaling pathways that control neuronal functions. Deterioration of mitochondrial functions has been widely reported in normal aging as well as in a spectrum of age-associated neurological diseases, including Parkinson's disease (PD). Evidences accumulated in the recent past provide not only advanced information on the causes of mitochondrial bioenergetics defects and redox imbalance in PD brains, but also much insight into mitochondrial biogenesis, quality control of mitochondrial proteins, and genes, which regulate intra- and extra-mitochondrial signaling that control the general health of neural cells. The mitochondrial quality control machinery is affected in aging and especially in PD, thus affecting intraneuronal protein transport and degradation, which are primarily responsible for accumulation of misfolded proteins and mitochondrial damage in sporadic as well as familial PD. Essentially we considered in the first half of this review, mitochondria-based targets such as mitochondrial oxidative stress and mitochondrial quality control pathways in PD, relevance of mitochondrial DNA mutations, mitophagy, mitochondrial proteases, mitochondrial flux, and finally mitochondria-based therapies possible for PD. Therapeutic aspects are considered in the later half and mitochondria-targeted antioxidant therapy, mitophagy enhancers, mitochondrial biogenesis boasters, mitochondrial dynamics modulators, and gene-based therapeutic approaches are discussed. The present review is a critical assessment of this information to distinguish some exemplary mitochondrial therapeutic targets, and provides a utilitarian perception of some avenues for therapeutic designs on identified mitochondrial targets for PD, a very incapacitating disorder of the geriatric population, world over.

The paths of mortality: how understanding the biology of aging can help explain systems behavior of single cells

Aging is a fundamental aspect of life, yet also one of the most confounding. In individual cells, aging results in a progressive decline which affects all organelles and reduces a cell's ability to maintain homeostasis. Because of the interconnected nature of cellular systems, the failure of even a single organelle can have cascading effects. We are just beginning to understand the dramatic physiological changes that occur during aging. Because most aging research has focused on population dynamics, or differences between wild-type and mutant populations, single-cell behavior has been largely overlooked. An open question is whether aging cells are defined by predictable sequences of physiological changes, or whether they proceed along divergent aging trajectories defined by whichever system begins to fail first. Can aging be best characterized by a cell-cycle like model with stereotyped states all cells progress through, or a Waddington landscape with divergent trajectories? Here we present work on understanding the changing physiological states of aging cells, why it will impact systems and synthetic biologists, and how the systems community can contribute significantly to the study of aging.

Dendrobium: Sources of Active Ingredients to Treat Age-Related Pathologies

Dendrobium represents one of the most important orchid genera, ornamentally and medicinally. Dendrobiums are sympodial epiphytic plants, which is a name they are worthy of, the name coming from Greek origin: "dendros", tree, and "bios", life. Dendrobium species have been used for a thousand years as first-rate herbs in traditional Chinese medicine (TCM). They are source of tonic, astringent, analgesic, antipyretic, and anti-inflammatory substances, and have been traditionally used as medicinal herbs in the treatment of a variety of disorders, such as, nourishing the stomach, enhancing production of body fluids or nourishing Yin. The Chinese consider Dendrobium as one of the fifty fundamental herbs used to treat all kinds of ailments and use Dendrobium tonic for longevity. This review is focused on main research conducted during the last decade (2006-2016) on Dendrobium plants and their constituents, which have been subjected to investigations of their pharmacological effects involving anticancer, anti-diabetic, neuroprotective and immunomodulating activities, to report their undeniable potential for treating age-related pathologies.