Average Life Span Research Articles

Effect of hulled Cannabis sativa L. seeds in a home-made diet for adult dogs

Homemade diets integrated with functional ingredients may help to ensure that companion animals have a good life quality given the rise in their average lifespan. This study investigates the effects of a complete and well-balanced homemade diet supplemented with hulled hemp seeds. Twelve adult dogs divided into two groups: CTRL, fed the basal diet and HEMP, fed the diet integrated hulled Cannabis sativa L. seeds (4 g/100g of ration) were enrolled in the trial. The following samples were collected: (a) individual faecal samples to assess the diet digestibility through an indirect method of acid-insoluble ash; b) blood samples to evaluate the oxidative state through an OXI adsorbent test; and c) rectal swabs for intestinal microbiota analysis (alpha- and beta-diversity and taxonomy). The results reveal that with respect to the commercial diet used in this study, our homemade diet increased the total and protein digestibility (total: 53.97 ± 2.54% and 58.20 ± 2.58%; p < .030; protein: 70.54 ± 2.01% and 82.78 ± 5.35%; p < .001). The change in diet positively altered the microbiota structure and increased beta-diversity index significantly (p < .010). The hemp seeds significantly (p < .001) reduced the oxidative stress in the serum. This study highlights how hemp increases the body’s defences and that a homemade diet promotes diversity in the gut microbial population.

Insights into the genetic influences of the microbiota on the life span of a host.

Escherichia coli (E. coli) mutant strains have been reported to extend the life span of Caenorhabditis elegans (C. elegans). However, the specific mechanisms through which the genes and pathways affect aging are not yet clear. In this study, we fed Drosophila melanogaster (fruit fly) various E. coli single-gene knockout strains to screen mutant strains with an extended lifespan. The results showed that D. melanogaster fed with E. coli purE had the longest mean lifespan, which was verified by C. elegans. We conducted RNA-sequencing and analysis of C. elegans fed with E. coli purE (a single-gene knockout mutant) to further explore the underlying molecular mechanism. We used differential gene expression (DGE) analysis, enrichment analysis, and gene set enrichment analysis (GSEA) to screen vital genes and modules with significant changes in overall expression. Our results suggest that E. coli mutant strains may affect the host lifespan by regulating the protein synthesis rate (cfz-2) and ATP level (catp-4). To conclude, our study could provide new insights into the genetic influences of the microbiota on the life span of a host and a basis for developing anti-aging probiotics and drugs.

Environmental Enrichment Improves Motor Function and Muscle Transcriptome of Aged Mice.

Aging results in the progressive decline of muscle strength. Interventions to maintain muscle strength may mitigate the age-related loss of physical function, thus maximizing health span. The work on environmental enrichment (EE), an experimental paradigm recapitulating aspects of an active lifestyle, has revealed EE-induced metabolic benefits mediated by a brain-fat axis across the lifespan of mice. EE initiated at 18-month of age shows a trend toward an increased mean lifespan. While previous work described EE's influences on the aging dynamics of several central-peripheral processes, its influence on muscle remained understudied. Here, the impact of EE is investigated on motor function, neuromuscular physiology, and the skeletal muscle transcriptome. EE is initiated in 20-month-old mice for a five-month period. EE mice exhibit greater relative lean mass that is associated with improved mobility and hindlimb grip strength. Transcriptomic profiling of muscle tissue reveals an EE-associated enrichment of gene expression within several metabolic pathways related to oxidative phosphorylation and the TCA cycle. Many mitochondrial-related genes-several of which participate in the electron transport chain-are upregulated. Stress-responsive signaling pathways are downregulated because of EE. The results suggest that EE improves motor function-possibly through preservation of mitochondrial function-even late in life.

Life history, nest longevity, sex ratio, and nest architecture of the fungus-growing ant Mycetosoritis hartmanni (Formicidae: Attina).

Mycetosoritis hartmanni is a rarely collected fungus-farming ant of North America. We describe life history and nest architecture for a M. hartmanni population in central Texas, USA. Colonies are monogynous with typically less than 100 workers (average 47.6 workers, maximum 148 workers). Nests occur always in sand and have a uniform architecture with 1-3 underground garden chambers arranged along a vertical tunnel, with the deepest gardens 50-70 cm deep. Foragers are active primarily between April and October. After reduced activity between November and February, egg laying by queens resumes in April, and the first worker pupae develop in early June. Reproductive females and males are reared primarily in July and August, with proportionally more females produced early in summer (protogyny). Mating flights and founding of new nests by mated females occur in late June to August, but may extend through September. For a cohort of 150 established nests (nests that had survived at least one year after nest founding), the estimated mortality rate was 0.41-0.53, the estimated average lifespan for these nests was 1.9-2.5 years, and the longest-living nests were observed to live for 6 years. These life-history parameters for M. hartmanni in central Texas are consistent with information from additional M. hartmanni nests observed throughout the range of this species from eastern Louisiana to southern Texas. Throughout its range in the USA, M. hartmanni can be locally very abundant in sun-exposed, sandy soil. Abundance of M. hartmanni seems so far relatively unaffected by invasive fire ants, and at present M. hartmanni does not appear to be an endangered species.

DEVELOPMENTAL PARAMETERS OF TRILOCHAVARIANS (LEPIDOPTERA: BOMBYCIDAE); A PEST OF WEEPING FIG, FICUSBENJAMINA IN PAKISTAN

The developmental parameters of Trilochavarianswere studied on weeping fig, Ficusbenjamina at 26°C ± 1.0 temperature and 65±5% relative humidity. The study showed that female laid 160-270 eggs in 2-6 layers on the dorsal side of the leaves. Some unmated female also laid 15-183 eggs in groups which never developed into larvae. 24 hours prior to hatching, the eggs turned black. Egg incubation period was 3.46±1.22 days on F. benjamina. The high fecundity increased the survival rate of T. varians.There were five larval instars which recorded in this study period. Last two instars caused more damage due to resemblance to hosts parts such as bark. There was a short, fleshy horn on the ninth abdominal segment. The developmental time of first, second, third, fourth and fifth larval instars was 2.44±0.82, 3.56±0.53, 3.72±0.26, 4.54±0.79 and 6.20±0.78 days, respectively. Boat shaped and yellow silken pupation was usually observed. The male and female mean longevity was 6.0 ± 1.171 and 11.4 ± 1.70 days. The dorsal side of the female forewings had pale reddish brown lines. The thorax, head, and abdomen of the female had darker reddish brown coloring than those of the male. Adult hind wings had reddish brown outer edges and were grayish in color. The average lifespan for male and female was 6.23±2.09 and 10.01±0.99 days, respectively. Thecurrent paper will lead to proper management practices for this pest

Estimating Disability-Free Life Expectancy of Malaysian Population Using the Sullivan's Approach

As we age, the chances of becoming disabled tend to increase due to an accumulation of health risks from a lifetime of illness, injury, and disability. This research examines the increasing life expectancy of the Malaysian population in relation to their disability status from 2015 to 2019. Disability-free life expectancy (DFLE) was computed using the Sullivan's approach; subsequently, compression or expansion of disability over the two observation years, 2015 and 2019, were analysed. Malaysian disability prevalence rates by age groups for 2015 and 2019 were used to execute this research. In addition, the respective mortality rates by age were gathered from the Department of Statistics of Malaysia. Results showed that, as life expectancy increases, the number of years lived without a disability would rise significantly while the anticipated number of years with a disability will be concurrently declining, suggesting evidence of disability compression. It was also observed that the median age at which the number of years spent with a disability higher than without a disability was 55 in 2015, then delayed to 67.5 in 2019. This study informs medical practitioners and health policymakers about the average lifespan of Malaysians without disabilities, which can indicate the population's general health status.

BASICS OF BIOLOGY OF AGING FOR MSU NON-BIOLOGISTS

The history of the creation of the course of lectures “Basics of the Biology of Aging” at the School of Biology of Lomonosov Moscow State University, as well as at the Department of Life Science and Engineering of Harbin Institute of Technology is brie y described. In the process of teaching this course, the author got the impression that its main provisions may also be of interest to students of non-biological specialties, who have recently been quite often involved in the work on the implementation of gerontological grants. This is largely determined, apparently, by the signi cantly increased funding for this kind of research in recent years. In turn, this is a consequence of the fact that the average life span of people in developed countries has increased dramatically over the past decades. However, the maximum life span has not changed much (it is now the same as it was thousands of years ago, it is just that the chances of living to the age of a centenarian have become much greater). If earlier people often died at an early age from various diseases not related to age (mainly infectious diseases), now, due to signi cant advances in medicine, most people live to old age. As a result, death “from aging” is becoming more common. At the same time, many people have a very vague idea of what aging is, what are its mechanisms and how to ght it. In this regard, in 2022, an interschool elective course of lectures was organized at MSU for students of any departments of the university, except for the School of Biology itself. It is called “Basics of the biology of aging, or everything you wanted to know about aging (but were afraid to ask).” The material of the lectures was specially adapted for students who are not biologists by their main specialty. The main emphasis in the course, consisting of 12 lectures, is made on the fundamental de nitions and methodical/methodological approaches used in gerontology. The article lists the questions submitted for the students’ test and brie y analyzes its results.

Premature Menopause and All-Cause Mortality and Life Span Among Women Older Than 40 Years in the NHANES I Epidemiologic Follow-Up Study: Propensity Score Matching Analysis.

Objective: Findings from studies of the long-term effect of premature menopause on risks of all-cause mortality in women are equivocal. We used the approach of propensity score matching to examine the causal association of premature menopause with all-cause mortality and life span among women older than 40 years. Methods: The data were from the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study. We calculated the propensity score of premature menopause using a logistic regression model, then matched premature menopause with nonpremature menopause according to the score and the ratio of 1:1. We estimated mortality hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazard models. We also analyzed and plotted the relationship between age at menopause and reproductive life span with all-cause mortality and life span. Results: The mean age of 1,210 women was 55.4 ± 10.8 years at baseline. The unadjusted and adjusted HRs of all-cause mortality for women with premature menopause were 1.46 (95% CI: 1.08-1.96) and 1.53 (95% CI: 1.13-2.08), respectively, compared to nonpremature menopause. Nonlinear associations were found between age at menopause, reproductive life span, all-cause mortality, and life span. Menopausal age <37.5 years of age or reproductive life span <24 years increased the risk of all-cause mortality. Women with menopausal age <39 years of age or reproductive life span <24 years had a lower mean life span than the overall average of 76 years. Conclusions: Premature menopause significantly increased all-cause mortality risk and shortened life span in women. As women's age at menopause or reproductive life span increases, their overall life span also tends to increase.

Japanese Dietary Habits and Their Impact on Health

In recent years, the impact of dietary patterns on human health has come under an increasing attention. A wealth of data suggests that healthy dietary patterns reduce the risk of diet-related diseases. Japan currently has the longest average life span in both sexes in the world. Japanese diet has always been known to be healthy, and its unique dietary habits are one of the key reasons for the longevity of the Japanese people. This study examines the relationship between certain non-communicable diseases' incidence and mortality and the Japanese diet. According to this study, in women, eating a lot of soy products is related to a reduction of breast cancer risk. however, relations between soy foods and prostate cancer in men is still debatable. Consumption of soy and fish is linked to a reduction in cardiovascular disease. The high-sodium diet in Japan is related to the increase of stroke and gastric cancer risks, while green tea and coffee are related to a lower risk of stroke. There are few studies that analyses the association between dietary patterns and related diseases in Japan, and this study provides ideas for analyzing the relationship between diet and health in Japan.

Backflow structures in turbulent pipe flows at low to moderate Reynolds numbers

The statistical characteristics and the evolution of the backflow structures are investigated in wall-bounded flows at Reynolds numbers up to $Re_{\tau }=1000$ . The backflow is caused by the joining of large-scale high- and low-speed structures in the vicinity of the wall and is formed at the tail tip of the low-speed structure. The distribution density of the backflow structures and the percentage area of the backflow region on the wall both increase with the Reynolds number. The backflow structures have an average lifespan of 8 wall units which is found to be slightly longer in the pipe than the channel, and they are convected downstream at the average velocities of the buffer region of approximately 10 wall units, similar to Cardesa et al. (J. Fluid Mech., vol. 880, 2019, R3). The backflow structures occasionally split and merge, and can form detached from the wall. Evidence shows that the split, merged and wall-detached backflow structures are caused by the near-wall structures. The split backflow structures are on average, larger and more spanwise-elongated which are split due to the spanwise shearing of the near-wall streaks. A backflow structure is formed detached from the wall when the trailing end of its carrier low-speed structure ‘sits’ on the near-wall high-speed streaks. The wall-detached backflow structures tend to become wall-attached by approaching the wall when undergoing a similar life cycle to the normal backflow of growth and decay with spanwise elongation because the backflow region at the tail of the low-speed structure is continuously pressed down to the wall by the high-speed structure driven by persistent vortical structures in the buffer region.

Mulberry leaves attenuate D-galactose-induced aging in vivo and in vitro.

Mulberry leaves contain many bioactive compounds and have been widely used in traditional medicines and functional foods for prevention and treatment of age-related diseases, such as diabetes, cognitive impairment and obesity-mediated liver cancer. Aging has an irreversible negative impact on human health for many years, even decades, before death, which is a social and economic burden on society. The objective of this study was to investigate the antioxidant and anti-aging effects of mulberry leaf extract (MLE) in vivo and in vitro. The Caenorhabditis elegans (C. elegans) was used as a model organism to observe the effects of different concentrations of MLE (1, 2, 4, 8 mg/mL) on nematodes' healthy lifespan, reproductive capacity, locomotion, stress resistance, and antioxidation. In addition, D-galactose (D-gal) induced liver aging in mice and L-02 cells were established. The antioxidant and anti-aging effects of MLE were evaluated by body weight, organ indexes, malondialdehyde (MDA), total superoxide dismutase (T-SOD), total antioxidant capacity (T-AOC), aspartate and alanine aminotransferases (AST and ALT), reactive oxygen species (ROS), mitochondrial membrane potential (MMP), hematoxylin and eosin (H&E), senescence-associated β-galactosidase (SA-β-Gal). Besides, the expressions of AMPK/SIRT1/PGC-1α and Nrf2-Keap1 were detected by Western blotting. MLE could significantly prolonged nematodes' average life span and improved most physiological indicators related to aging of C. elegans. Moreover, Treatment with MLE ameliorated the decreased body weight and organ index (weight of organ/body weight) in model mice, and protected against oxidative stress in mice and liver cells, in a dose-dependent manner, up-regulating T-SOD and T-AOC, while reducing ROS and MDA levels. MLE decreased both liver and cell levels of AST and ALT, and enhanced the mitochondrial membrane potential. MLE activated the AMPK/SIRT1/PGC-1α pathways, participated in mitochondrial biosynthesis and oxidative metabolism and delayed D-gal-induced aging. MLE promoted the accumulation of Nrf2 in the nucleus, indicating that the improved oxidative stress response was mediated by the Nrf2-Keap1 pathway in vivo and in vitro. MLE appeared to have great potential for stimulating the oxidative stress response and attenuating the aging process of in vivo and in vitro, and provide a novel health-promoting resource against aging and aging-related diseases.

Human Mesenchymal Stem Cells and Innovative Scaffolds for Bone Tissue Engineering Applications.

Stem cell-based therapy is a significant topic in regenerative medicine, with a predominant role being played by human mesenchymal stem cells (hMSCs). The hMSCs have been shown to be suitable in regenerative medicine for the treatment of bone tissue. In the last few years, the average lifespan of our population has gradually increased. The need of biocompatible materials, which exhibit high performances, such as efficiency in bone regeneration, has been highlighted by aging. Current studies emphasize the benefit of using biomimetic biomaterials, also known as scaffolds, for bone grafts to speed up bone repair at the fracture site. For the healing of injured bone and bone regeneration, regenerative medicine techniques utilizing a combination of these biomaterials, together with cells and bioactive substances, have drawn a great interest. Cell therapy, based on the use of hMSCs, alongside materials for the healing of damaged bone, has obtained promising results. In this work, several aspects of cell biology, tissue engineering, and biomaterials applied to bone healing/regrowth will be considered. In addition, the role of hMSCs in these fields and recent progress in clinical applications are discussed. Impact Statement The restoration of large bone defects is both a challenging clinical issue and a socioeconomic problem on a global scale. Different therapeutic approaches have been proposed for human mesenchymal stem cells (hMSCs), considering their paracrine effect and potential differentiation into osteoblasts. However, different limitations are still to be overcome in using hMSCs as a therapeutic opportunity in bone fracture repair, including hMSC administration methods. To identify a suitable hMSC delivery system, new strategies have been proposed using innovative biomaterials. This review provides an update of the literature on hMSC/scaffold clinical applications for the management of bone fractures.

Aging Rate Indicators: Speedometers for Aging Research in Mice.

A "biomarker of aging" is conceptualized as an index of how far an individual has moved along the path from youth to old age. In contrast, an aging rate indicator (ARI) represents a measure of speed, rather than distance, that is, a measure of how rapidly the individual is moving toward the phenotypic changes typical of old age. This essay presents and reviews recent data suggesting common characteristics of slow-aging mice, whether the slowed aging is caused by a mutant allele, the calorie restriction diet, or drugs that slow aging and extend mean and maximal lifespan. Some of the candidate ARIs, shared by nine varieties of slow-aging mice, are physiological changes seen in fat, fat-associated macrophages, muscle, liver, brain, and plasma. Others are molecular measurements, reflecting activity of mTORC1, selective mRNA translation, or each of six MAP kinases in two distinct MAPK cascades in liver, muscle, or kidney. Changes in ARIs are notable in young adult mice after 8 months of drug or diet exposure, are detectable in mutant mice at least as early as 4-6 months of age, and persist until at least 18-22 months. Many of the candidate ARIs are thought to play an influential role in cognition, inflammation, exercise responses, and control of metabolic rate, and are thus plausible as modulators of age-related physiological and neurological illnesses. In principle, screening for drugs that induce alterations in ARIs in normal young adult mice might facilitate the search for preventive medicines that can retard aging and late-life illnesses in mice or in human populations.

Systematic exclusion at study commencement masks earlier menopause for Black women in the Study of Women's Health Across the Nation (SWAN).

Shorter average lifespans for minoritized populations are hypothesized to stem from 'weathering' or accelerated health declines among minoritized individuals due to systemic marginalization. However, evidence is mixed on whether racial/ethnic differences exist in reproductive ageing, potentially due to selection biases in cohort studies that may systematically exclude 'weathered' participants. This study examines racial/ethnic disparities in the age of menopause after accounting for differential selection 'into' (left truncation) and 'out of' (right censoring) a cohort of midlife women. Using data from the Study of Women's Health Across the Nation (SWAN) cross-sectional screener (N = 15 695) and accompanying ∼20-year longitudinal cohort (N = 3302) (1995-2016), we adjusted for potential selection bias using inverse probability weighting (left truncation) to account for socio-demographic/health differences between the screening and cohort study, and multiple imputation (right censoring) to estimate racial/ethnic differences in age at menopause (natural and surgical). Unadjusted for selection, no Black/White differences in menopausal timing [hazard ratio (HR)=0.98 (0.86, 1.11)] were observed. After adjustment, Black women had an earlier natural [HR = 1.13 (1.00, 1.26)] and surgical [HR= 3.21 (2.80, 3.62)] menopause than White women with natural menopause-corresponding to a 1.2-year Black/White difference in menopause timing overall. Failure to account for multiple forms of selection bias masked racial/ethnic disparities in the timing of menopause in SWAN. Results suggest that there may be racial differences in age at menopause and that selection particularly affected the estimated menopausal age for women who experienced earlier menopause. Cohorts should consider incorporating methods to account for all selection biases, including left truncation, as they impact our understanding of health in 'weathered' populations.

Longevity toxicity after chronic α -endosulfan exposure in wild population of Drosophila melanogaster Oregon-R (Diptera: Drosophilidae)

The rapid increase in the world population causes different problems such as nutrition and shelter. In this case, people brutally destroy arable land to shelter, and concretization is rapidly spreading. In addition, it is necessary to increase the amount of products to be taken from the limited agricultural areas for the food needs of the increasing population. The decrease in agricultural areas appears as a factor that reduces the amount of product taken from the unit area. In addition, weeds and especially insects reduce the yield, storage, and marketing quality of products obtained from restricted areas. This type of plant products can also be considered a disease carrier vector in the food chain. To increase the yield, various insecticides have been developed against target organisms such as insects and one of these insecticides is α-endosulfan. However, non-target organisms living in the same ecosystem can also be affected by all these insecticides.&#x0D; In the present study, it was researched whether the chronic α-endosulfan application has an effect on longevity in non-target organisms. According to the data obtained, α-endosulfan shortened the maximum and mean lifespan in both male and female populations of the Oregon-R wild strain of Drosophila melanogaster based on dose-time interaction. The shortening observed in life span for both populations was statistically significant (p

Evaluation of the orally bioavailable 4-phenylbutyrate-tethered trichostatin A analogue AR42 in models of spinal muscular atrophy

Proximal spinal muscular atrophy (SMA) is a leading genetic cause for infant death in the world and results from the selective loss of motor neurons in the spinal cord. SMA is a consequence of low levels of SMN protein and small molecules that can increase SMN expression are of considerable interest as potential therapeutics. Previous studies have shown that both 4-phenylbutyrate (4PBA) and trichostatin A (TSA) increase SMN expression in dermal fibroblasts derived from SMA patients. AR42 is a 4PBA-tethered TSA derivative that is a very potent histone deacetylase inhibitor. SMA patient fibroblasts were treated with either AR42, AR19 (a related analogue), 4PBA, TSA or vehicle for 5 days and then immunostained for SMN localization. AR42 as well as 4PBA and TSA increased the number of SMN-positive nuclear gems in a dose-dependent manner while AR19 did not show marked changes in gem numbers. While gem number was increased in AR42-treated SMA fibroblasts, there were no significant changes in FL-SMN mRNA or SMN protein. The neuroprotective effect of this compound was then assessed in SMNΔ7 SMA (SMN2+/+;SMNΔ7+/+;mSmn−/−) mice. Oral administration of AR42 prior to disease onset increased the average lifespan of SMNΔ7 SMA mice by ~ 27% (20.1 ± 1.6 days for AR42-treated mice vs. 15.8 ± 0.4 days for vehicle-treated mice). AR42 treatment also improved motor function in these mice. AR42 treatment inhibited histone deacetylase (HDAC) activity in treated spinal cord although it did not affect SMN protein expression in these mice. AKT and GSK3β phosphorylation were both significantly increased in SMNΔ7 SMA mouse spinal cords. In conclusion, presymptomatic administration of the HDAC inhibitor AR42 ameliorates the disease phenotype in SMNΔ7 SMA mice in a SMN-independent manner possibly by increasing AKT neuroprotective signaling.

Comparison of In-Rumen Systems for Monitoring the Physiological State of Cattle

This paper explores a method for the early detection of subacute rumen acidosis through continuous monitoring of rumen content acidity using wireless pH sensors. The study emphasizes the importance of reliable device operation and measurement accuracy as primary requirements for such devices. (Research purpose) This study aims to evaluate the functionality and accuracy of the eBolus (USA) and BoviSan (Russia, FSBSI FSAC VIM) sensors throughout their declared service life of 150 days. (Materials and methods) Three dairy cows with a rumen fistula were administered two boluses from each manufacturer during a period of 154 days. In order to ensure accurate measurements, the boluses were activated and calibrated prior to use. On the first day of data collection, the activated and calibrated boluses were sequentially immersed in buffer solutions with a pH of 4 and pH of 7. The buffer solutions were maintained at a controlled temperature of 39 degrees Celsius for a minimum of 2 hours. At 14-day intervals, the boluses were extracted from the rumen and subjected to retesting in buffer solutions. (Results and discussion) For BoviSan, the confidence interval for the mean difference suggests a systematic negative pH bias (– 0.33 to – 0.25). The average lifespan of the eBolus was determined to be 82 days, with a range of 28 to 126 days. In contrast, BoviSan boluses consistently recorded pH levels throughout their announced lifespan. Statistical analysis of the data revealed a 95% confidence interval for the mean pH difference of the eBolus boluses (– 0.02 to 0.19), indicating no significant bias. Conversely, the confidence interval for the mean difference in pH for BoviSan suggested a consistent negative bias (– 0.33 to – 0.25). (Conclusions) In practical applications, it is essential to ensure enhanced reliability of eBolus boluses, while prioritizing higher measurement accuracy with BoviSan boluses.

Age-related decline of various cognitive functions in well-experienced male rats treated with the putative anti-aging compound (2R)-1-(1-benzofuran-2-yl)-N-propylpentane-2-amine ((-)BPAP)

Aging-associated cognitive disorders lack proper medication. To meet this need translation-wise, modification of the animal models is also required. In the present study, effect of the putative anti-aging compound (2R)-1-(1-benzofuran-2-yl)-N-propylpentane-2-amine ((-)BPAP, a deprenyl derivative) on age-related cognitive decline was investigated in experienced, aged Long-Evans rats. During their lifetime, animals had acquired knowledge in various cognitive assays. Their performance in these tests was then parallel followed from the age of 27 months until their death meanwhile half of them were treated with BPAP. Cognitive performance in various tasks showed different sensitivities/resistances to age-related impairment. Pot jumping performance (motor skill-learning) started to impair first, at 21 months of age, followed by decreasing performance in five-choice serial reaction time task (attention) at 26 months. Navigation performance in Morris water maze (spatial learning) started to decline at 31 months. Performance in a cooperation task (social cognition) started to decline the latest, at 34 months. Our findings suggest that in this process, the primary factor was the level of motivation to be engaged with the task and not losing the acquired knowledge. The average lifespan of the tested rat population was 36 months. BPAP could not improve the cognitive performance; neither could it prolong lifespan. A possible reason might be that dietary restriction and lifelong cognitive engagement had beneficial effects on cognitive capabilities and lifespan creating a “ceiling effect” for further improvement. The results confirmed that experienced animals provide a translationally relevant model to study age-related cognitive decline and measure the effect of putative anti-aging compounds.

Aging – What it is and how to measure it

The current understanding of the biology of aging is largely based on research aimed at identifying factors that influence lifespan. However, lifespan as a sole proxy measure of aging has limitations because it can be influenced by specific pathologies (not generalized physiological deterioration in old age). Hence, there is a great need to discuss and design experimental approaches that are well-suited for studies targeting the biology of aging, rather than the biology of specific pathologies that restrict the lifespan of a given species. For this purpose, we here review various perspectives on aging, discuss agreement and disagreement among researchers on the definition of aging, and show that while slightly different aspects are emphasized, a widely accepted feature, shared across many definitions, is that aging is accompanied by phenotypic changes that occur in a population over the course of an average lifespan. We then discuss experimental approaches that are in line with these considerations, including multidimensional analytical frameworks as well as designs that facilitate the proper assessment of intervention effects on aging rate. The proposed framework can guide discovery approaches to aging mechanisms in all key model organisms (e.g., mouse, fish models, D. melanogaster, C. elegans) as well as in humans.

Mechanisms Governing the Formation and Long-Term Sustainment of a Northeastward Moving Southwest Vortex

From 10 July to 12 July 2021, a long-lived (~66 h) southwest vortex (SWV), moved from Southwest China to Northeast China and caused a series of heavy rainfall events. This SWV case was rarely seen, as its lifespan was much longer than the SWVs’ mean lifespan, and the vast majority of SWVs showed a quasi-stationary behavior. It was found that the SWV formed and sustained in favorable background environments, which were characterized by a strong upper-level divergence (related to the South Asia High), a notable middle-tropospheric warm advection (related to a shortwave trough), and a vigorous low-level jet. The SWV showed remarkable interactions with a middle-tropospheric mesoscale vortex. The strong southwesterly wind in the eastern section of a deep shortwave trough east of the Tibetan Plateau acted as the steering flow for the northeastward movement of both vortices. Vorticity budget showed that the convergence-related vertical stretching dominated the SWV’s formation and development; the convection-related upward transport of cyclonic vorticity was the most favorable factor for the SWV’s sustainment, whereas, during the decaying stage, the SWV dissipated mainly due to the tilting effects and the net export transport of cyclonic vorticity. Backward trajectory analyses showed that most of the air particles that formed the SWV (at its formation time) were sourced from the lower troposphere. These air particles mainly ascended and experienced a rapid increase in cyclonic vorticity during the SWV’s formation stage. The topography of the Yunnan–Guizhou Plateau was crucial for the SWV’s formation, as around a half of the air particles (that formed the SWV) came from this region. Most of these air particles enhanced in their cyclonic vorticity and convergence when they descended along the topography of the plateau.