Age-dependent Manner Research Articles

The NAC transcription factor ZmNAC132 regulates leaf senescence and male fertility in maize

Leaf senescence is an integral step in the final stages of plant development, as nutrient remobilization from leaves to sink organs is accomplished during this process. NACs compose a large superfamily of plant-specific TFs involved in multiple plant development processes. Here, we identified a maize NAC TF, ZmNAC132, involved in leaf senescence and male fertility. ZmNAC132 expression was tightly linked to leaf senescence in an age-dependent manner. Knockout of ZmNAC132 led to delays in chlorophyll degradation and leaf senescence, whereas overexpression of ZmNAC132 had the opposite effects. ZmNAC132 could bind to and transactivate the promoter of ZmNYE1, a major chlorophyll catabolic gene, to accelerate chlorophyll degradation during leaf senescence. Moreover, ZmNAC132 affected male fertility through the upregulation of ZmEXPB1, an expansin-encoding gene associated with sexual reproduction and other related genes. Together, the results show that ZmNAC132 participates in the regulation of leaf senescence and male fertility through the targeting of different downstream genes in maize.

Acarbose Mitigates Age-Dependent Alterations in Erythrocyte Membrane Transporters During Aging in Rats.

Acarbose (ACA), a well-studied and effective inhibitor of α-amylase and α-glucosidase, is a postprandial-acting antidiabetic medicine. The membrane of the erythrocyte is an excellent tool for analyzing different physiological and biochemical activities since it experiences a range of metabolic alterations throughout aging. It is uncertain if ACA modulates erythrocyte membrane activities in an age-dependent manner. As a result, the current study was conducted to explore the influence of ACA on age-dependent deteriorated functions of transporters/exchangers, disrupted levels of various biomarkers such as lipid hydroperoxides (LHs), protein carbonyl (PCO), sialic acid (SA), total thiol (-SH), and erythrocyte membrane osmotic fragility. In addition to a concurrent increase in Na+/H+ exchanger activity and concentration of LH, PCO, and osmotic fragility, we also detected a considerable decrease in membrane-linked activities of Ca2+-ATPase (PMCA) and Na+/K+-ATPase (NKA), as well as concentrations of SA and -SH in old-aged rats. The aging-induced impairment of the activities of membrane-bound ATPases and the changed levels of redox biomarkers were shown to be effectively restored by ACA treatment.

Sex, T Cells, and the Microbiome in Natural ABO Antibody Production in Mice.

"Natural" ABO antibodies (Abs) are produced without known exposure to A/B carbohydrate antigens, posing significant risks for hyperacute rejection during ABO-incompatible transplantation. We investigated anti-A "natural" ABO antibodies versus intentionally induced Abs with regard to the need for T-cell help, the impact of sex, and stimulation by the microbiome. Anti-A was measured by hemagglutination assay of sera from untreated C57BL/6 wild-type (WT) or T cell-deficient mice of both sexes. Human ABO-A reagent blood cell membranes were injected intraperitoneally to induce anti-A Abs. The gut microbiome was eliminated by maintenance of mice in germ-free housing. Compared with WT mice, CD4 + T-cell knockout (KO), major histocompability complex-II KO, and αβ/γδ T-cell receptor KO mice produced much higher levels of anti-A nAbs; females produced dramatically more anti-A nAbs than males, rising substantially with puberty. Sensitization with human ABO-A reagent blood cell membranes did not induce additional anti-A in KO mice, unlike WT. Sex-matched CD4 + T-cell transfer significantly suppressed anti-A nAbs in KO mice and rendered mice responsive to A-sensitization. Even under germ-free conditions, WT mice of several strains produced anti-A nAbs, with significantly higher anti-A nAbs levels in females than males. Anti-A nAbs were produced without T-cell help, without microbiome stimulation, in a sex- and age-dependent manner, suggestive of a role for sex hormones in regulating anti-A nAbs. Although CD4 + T cells were not required for anti-A nAbs, our findings indicate that T cells regulate anti-A nAb production. In contrast to anti-A nAbs, induced anti-A production was T-cell dependent without a sex bias.

Effects of RNA M6A demethylase ALKBH5 gene deficiency on morphology and function of cerebellum in aged mice

Objective: To investigate the effects of RNA m6A demethylase ALKBH5 gene deficiency on cerebellar morphology and function in the aged mice, and to explore the role of ALKBH5 in cerebellar degeneration. Methods: Western blot was performed to detect the protein level of ALKBH5 in the cerebellum of wild-type mice of various ages. The expression of NeuN, Calbindin-D28K, MAP2, GFAP and other proteins in the cerebella of middle-aged (12-month-old) and aged (18-month-old) wild-type mice and ALKBH5-/- mice was examined using immunohistochemistry. The balance beam test and gait analysis were performed to test the balance ability and motor coordination of the mice. Results: With aging of the mice, the expression of ALKBH5 in the cerebellum increased gradually in an age-dependent manner. In the aged mice, but not middle-aged mice, the body weight, whole brain weight and cerebellum weight of ALKBH5-/- mice decreased by 15%, 10% and 21%, respectively (P<0.05). The expression of ALKBH5 in the Purkinje cells was much higher than that in other types of neural cells. Correspondingly, ALKBH5-deficiency caused 40% reduction in the number of Purkinje cells, as well as the length and density of neuronal dendrites in the aged mice (P<0.01). In addition, the time for the aged ALKBH5-/- mice to pass the balance beam was 70% longer than that of the wild type mice of the same age, with unstable gaits (P<0.01). Conclusions: Gene deficiency of RNA m6A demethylase ALKBH5 causes cerebellar atrophy, Purkinje neuron loss and damage in the aged mice. These changes eventually affect mice's motor coordination and balance ability. These results suggest that imbalanced RNA m6A methylation may lead to neurodegenerative lesions in the cerebellum of mice.

Early retinal deprivation crossmodally alters nascent subplate circuits and activity in the auditory cortex during the precritical period.

Sensory perturbation in one modality results in the adaptive reorganization of neural pathways within the spared modalities, a phenomenon known as "crossmodal plasticity," which has been examined during or after the classic "critical period." Because peripheral perturbations can alter the auditory cortex (ACX) activity and functional connectivity of the ACX subplate neurons (SPNs) even before the critical period, called the precritical period, we investigated if retinal deprivation at birth crossmodally alters the ACX activity and SPN circuits during the precritical period. We deprived newborn mice of visual inputs after birth by performing bilateral enucleation. We performed in vivo widefield imaging in the ACX of awake pups during the first two postnatal weeks to investigate cortical activity. We found that enucleation alters spontaneous and sound-evoked activities in the ACX in an age-dependent manner. Next, we performed whole-cell patch clamp recording combined with laser scanning photostimulation in ACX slices to investigate circuit changes in SPNs. We found that enucleation alters the intracortical inhibitory circuits impinging on SPNs, shifting the excitation-inhibition balance toward excitation and this shift persists after ear opening. Together, our results indicate that crossmodal functional changes exist in the developing sensory cortices at early ages before the onset of the classic critical period.

Fat mass and obesity-associated factor (FTO)-mediated N6-methyladenosine regulates spermatogenesis in an age-dependent manner

N6-methyladenosine (m6A) is the most prevalent reversible RNA modification in the mammalian transcriptome. It has recently been demonstrated that m6A is crucial for male germline development. Fat mass and obesity-associated factor (FTO), a known m6A demethylase, is widely expressed in human and mouse tissues and is involved in manifold biological processes and human diseases. However, the function of FTO in spermatogenesis and male fertility remains poorly understood. Here, we generated an Fto knockout mouse model using CRISPR/Cas9-mediated genome editing techniques to address this knowledge gap. Remarkably, we found that loss of Fto in mice caused spermatogenesis defects in an age-dependent manner, resulting from the attenuated proliferation ability of undifferentiated spermatogonia and increased male germ cell apoptosis. Further research showed that FTO plays a vital role in the modulation of spermatogenesis and Leydig cell maturation by regulating the translation of the androgen receptor in an m6A-dependent manner. In addition, we identified two functional mutations of FTO in male infertility patients, resulting in truncated FTO protein and increased m6A modification in vitro. Our results highlight the crucial effects of FTO on spermatogonia and Leydig cells for the long-term maintenance of spermatogenesis and expand our understanding of the function of m6A in male fertility.

Tributyltin exposure during gestation and lactation changes the hormone profile of the offspring in a sex- and age-dependent manner

Searchable abstracts of presentations at key conferences in endocrinology ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

γδ T Cells Contribute to Immunopathology During Neonatal Sepsis in an Age-Dependent Manner

Abstract Bacterial bloodstream infections (BSIs) remain a significant contributor to neonatal mortality, despite improved hygienic practices in the NICU. Although the understanding of the neonatal immune system has increased greatly over the past decade, why neonates, but not older infants, are susceptible to severe adverse immunopathology – sepsis – in response to bacteremia remains poorly understood. In the present study, we find that postnatal day 5 (P5) neonatal γδ T cells are highly inflammatory during a mouse model of E. coliBSI and are associated with mortality. Furthermore, γδ T cells in P5 mice rapidly produce pro-inflammatory cytokines, such as IFN-γ, IL-17A, and TNFα, and increase their expression of cytotoxic molecules such as granzyme and perforin. Interestingly, blockade of the γδ TCR in vivois associated with increased survival and decreased pro-inflammatory cytokine production in P5 pups. Signaling and activation via the γδ TCR was confirmed using Nur77-GFP mice, with P5 γδ T cells significantly upregulating expression of Nur77 during in vivoinfection. Intriguingly, E. coliBSI in P15 pups results in markedly different γδ T cells responses compared to neonates, despite similar systemic bacterial burden. During bacterial bloodstream infection, P15 pups do not experience mortality, and unergo minimal activation of γδ T cells and production of IFN-γ, IL-17A, and TNFα. Furthermore, BSI infection in P15 Nur77-GFP mice revealed lack of TCR signaling in P15 γδ T cells at this age. In conclusion, the present study reveals rapid age-dependent changes to γδ T cell responses during early life and suggests neonates may be uniquely susceptible to γδ T cell-mediated immunopathology during bacterial bloodstream infection. T32 AI170478-01

Abstract 588: Androgen Promotes Aortic Aneurysms Via Suppressing PD-1 In Male Mice

Objective: Male sex is a well-established risk factor for abdominal aortic aneurysms but the underlying mechanisms remain to be fully understood. Our lab reported aldosterone and high salt (aldo-salt) induced aortic aneurysms in an age-dependent manner in male mice but whether it shows sex dimorphisms as in human is unknown. The current study tested the hypothesis that male mice are more susceptible to aldo-salt induced aortic aneurysms through androgen mediation and investigated the potential mechanisms. Results: Ten-month-old male and female mice were used in all experiments. We first demonstrated the sex differences in the aldo-salt model with 70% incidence in male mice (7/10) compared to complete protection in female mice (0/9). Next, we showed androgen and androgen receptor (AR) mediated the process by several independent experiments: 1) orchiectomy provided strong protection (13.3%, 2/15) compared to sham control (69.2%, 9/13); 2) Exogenous DHT administration to orchiectomized mice restored the aneurysms formation (55%, 6/11); 3) inhibition of AR function by drug decreased total incidence compared to control (2/11 vs. 7/11). To dissect the mechanism, we conducted bulk RNA sequencing in aortas from 3 groups of mice given aldo-salt 1) intact male mice; 2) orchiectomized mice; and 3) orchiectomized mice with DHT. Through a series of bioinformatic analyses, we found PD-1 signaling pathway was significantly enriched in orchiectomized mice compared to control and reversed by DHT addition. Next, we found a significantly higher expression of PD-1 in spleen from orchiectomized mice than sham mice with aldo-salt presence, at both protein and mRNA levels. Mechanistically we showed AR could bind to PD-1 promoter region and suppressed PD-1 expression. Finally, we injected αPD-1 antibody or control IgG antibody to orchiectomized mice during the aldo-salt administration to confirm phenotypes. Results showed that neutralization of PD-1 partially abolished the orchiectomy protection (0/8 vs. 5/12). Conclusions: Our results demonstrated that male mice are more susceptible to aldosterone and high salt-induced aortic aneurysms. Androgen and its receptor mediate the high susceptibility in male mice partially through PD-1 signaling pathway.

Myeloid-KLF2 knockout neonatal mice experience mortality from lipopolysaccharide in an age-dependent and cell-specific manner

Abstract Background: Preterm neonates exhibit increased mortality from Gram negative sepsis as compared to term neonates. The innate immune system is at a critical phase of development during the neonatal period. Mechanisms underlying activation of the preterm neonatal innate immune response are poorly understood. Our prior data has shown that Kruppel-like factor (KLF)-2 is a critical transcription factor to maintain murine myeloid cells in a quiescent state. We hypothesize that myeloid KLF2 plays a critical role in the neonatal immune response in Gram negative sepsis. Methods: Preterm neonatal (P4) and term neonatal (P12) myeloid KLF2 knockout (MyK2KO) and age matched Cre mice were given 5ug/gm of E. coli O55:B5 lipopolysachharide (LPS) via intraperitoneal (i.p.) injection. For cell depletion studies, antibodies were injected i.p. 24 hours prior to LPS injection, followed by a repeat dose 24h after LPS. Ly6G antibody was used for neutrophil depletion, CD115 for monocyte depletion and equal dose of both for depletion of both cell lines. Results: P4 MyK2KO mice have significantly increased mortality within 48 h of LPS exposure as compared to P4 Cre mice (81% vs 41%, n=19, p&amp;lt;0.01 χ2test). At P12, there is 100% survival of both groups of mice. Depletion of either neutrophils, monocytes or both together, decreased the mortality in P4 MyK2KO mice from 81% to 55%. Conclusion: Preterm neonatal mice lacking myeloid KLF2 have an exaggerated response to LPS as compared to term neonatal MyK2KO or age-matched control mice. In vivo depletion of neutrophils, monocytes or both prior to LPS attenuates this response. Future studies will focus on the mechanism underlying the postnatal age-specific and cell-specific role of KLF2 in the neonatal innate immune response. Supported by grants from Rainbow Faculty Pilot Grant (Mukherjee PI) and NIH (R01 HL142647 Nayak PI)

Regional and age-dependent changes in ubiquitination in cellular and mouse models of spinocerebellar ataxia type 3.

Spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease, is the most common dominantly inherited ataxia. SCA3 is caused by a CAG repeat expansion in the ATXN3 gene that encodes an expanded tract of polyglutamine in the disease protein ataxin-3 (ATXN3). As a deubiquitinating enzyme, ATXN3 regulates numerous cellular processes including proteasome- and autophagy-mediated protein degradation. In SCA3 disease brain, polyQ-expanded ATXN3 accumulates with other cellular constituents, including ubiquitin (Ub)-modified proteins, in select areas like the cerebellum and the brainstem, but whether pathogenic ATXN3 affects the abundance of ubiquitinated species is unknown. Here, in mouse and cellular models of SCA3, we investigated whether elimination of murine Atxn3 or expression of wild-type or polyQ-expanded human ATXN3 alters soluble levels of overall ubiquitination, as well as K48-linked (K48-Ub) and K63-linked (K63-Ub) chains. Levels of ubiquitination were assessed in the cerebellum and brainstem of 7- and 47-week-old Atxn3 knockout and SCA3 transgenic mice, and also in relevant mouse and human cell lines. In older mice, we observed that wild-type ATXN3 impacts the cerebellar levels of K48-Ub proteins. In contrast, pathogenic ATXN3 leads to decreased brainstem abundance of K48-Ub species in younger mice and changes in both cerebellar and brainstem K63-Ub levels in an age-dependent manner: younger SCA3 mice have higher levels of K63-Ub while older mice have lower levels of K63-Ub compared to controls. Human SCA3 neuronal progenitor cells also show a relative increase in K63-Ub proteins upon autophagy inhibition. We conclude that wild-type and mutant ATXN3 differentially impact K48-Ub- and K63-Ub-modified proteins in the brain in a region- and age-dependent manner.

Maturation of a cortical-amygdala circuit limits sociability in male rats.

Prefrontal cortical maturation coincides with adolescent transitions in social engagement, suggesting that it influences social development. The anterior cingulate cortex (ACC) is important for social interaction, including ACC outputs to the basolateral amygdala (BLA). However, little is known about ACC-BLA sensitivity to the social environment and if this changes during maturation. Here, we used brief (2-hour) isolation to test the immediate impact of changing the social environment on the ACC-BLA circuit and subsequent shifts in social behavior of adolescent and adult rats. We found that optogenetic inhibition of the ACC during brief isolation reduced isolation-driven facilitation of social interaction across ages. Isolation increased activity of ACC-BLA neurons across ages, but altered the influence of ACC on BLA activity in an age-dependent manner. Isolation reduced the inhibitory impact of ACC stimulation on BLA neurons in a frequency-dependent manner in adults, but uniformly suppressed ACC-driven BLA activity in adolescents. This work identifies isolation-driven alterations in an ACC-BLA circuit, and the ACC itself as an essential region sensitive to social environment and regulates its impact on social behavior in both adults and adolescents.

Annual stability of the plasma Aß40/42 ratio and associated factors.

The plasma Aß40/42 ratio is a biomarker of brain amyloidosis. However, the threshold difference between amyloid positivity and negativity is only 10-20% and fluctuates with circadian rhythms, aging, and APOE-ε4 during the decades of evolution of Alzheimer's disease. Plasma Aß40 and Aß42 levels in 1472 participants aged between 19 and 93 years in the Iwaki Health Promotion Project for 4 years were statistically analyzed. The means and standard deviations of annual inter-individual coefficients of variation were 5.3 ± 3.2% for Aß40, 7.8 ± 4.6% for Aß42, and 6.4 ± 4.1% for the Aß40/42 ratio. No significant age-dependent changes were observed in inter-individual coefficients of variation. Age-dependent increases in Aβ42 levels were suppressed, whereas those in the Aβ40/42 ratio were enhanced in APOE-ε4 carriers. The change points of Aß42, Aß40, and the Aß40/42 ratio were 36.4, 38.2, and 43.5 years, respectively. In the presence of APOE-ε4, the Aß40/42 ratio increased in middle-aged and elderly subjects while Aβ42 levels decreased in elderly subjects. Individual values for Aß40, Aß42, and the Aß40/42 ratio did not fluctuate annually or in an age-dependent manner. If the plasma Aβ40/42 ratio changes by more than 14.7% (+2 standard deviations) relative to age- and APOE-ε4-adjusted normal annual fluctuations, other biomarkers also need to be examined.

Dynamics of oral microbiome acquisition in healthy infants: A pilot study.

The human oral microbiota is one of the most complex bacterial communities in the human body. However, how newborns initially acquire these bacteria remains largely unknown. In this study, we examined the dynamics of oral microbial communities in healthy infants and investigated the influence of the maternal oral microbiota on the acquisition of the infant's oral microbiota. We hypothesized that the infant oral microbial diversity increases with age. One hundred and sixteen whole-salivary samples were collected from 32 healthy infants and their biological mothers during postpartum and 9- and 15-month well-infant visits. Bacterial genomic DNA was extracted and sequenced by Human Oral Microbe Identification using Next Generation Sequencing (HOMINGS) methods. The Shannon index was used to measure the microbial diversity of the infant-mother dyads (alpha diversity). The microbial diversity between the mother-infant dyads (beta-diversity) was calculated using the weighted non-phylogenetic Bray-Curtis distance in QIIME 1.9.1. Core microbiome analysis was performed using MicrobiomeAnalyst software. Linear discriminant analysis coupled with effect size analysis was used to identify differentially abundant features between mother and infant dyads. A total of 6,870,571 16S rRNA reads were generated from paired mother-infant saliva samples. Overall, oral microbial profiles significantly differed between the mother and infant groups (p < 0.001). The diversity of the salivary microbiomes in the infants increased in an age-dependent manner, whereas the core microbiome of the mothers remained relatively stable during the study period. Breastfeeding and gender did not affect the microbial diversity in infants. Moreover, infants had a greater relative abundance of Firmicutes and a lower abundance of Actinobacteria, Bacteroidetes, Fusobacteria, and Proteobacteria than their mothers. The SparCC correlation analysis demonstrated constant changes in infants' oral microbial community network (p < 0.05). This study provides new evidence that the oral cavities of infants are colonized by a distinct group of bacterial species at birth. The acquisition and diversity of changes in oral microbial composition are dynamic during the first year of an infant's life. Before reaching the second birthday, the composition of the oral microbial community could be more similar to that of their biological mothers.

Mic60 is essential to maintain mitochondrial integrity and to prevent encephalomyopathy.

Mitochondrial encephalomyopathies (ME) are frequently associated with mutations of mitochondrial DNA, but the pathogenesis of a subset of ME (sME) remains elusive. Here we report that haploinsufficiency of a mitochondrial inner membrane protein, Mic60, causes progressive neurological abnormalities with insulted mitochondrial structure and neuronal loss in mice. In addition, haploinsufficiency of Mic60 reduces mitochondrial membrane potential and cellular ATP production, increases reactive oxygen species, and alters mitochondrial oxidative phosphorylation complexes in neurons in an age-dependent manner. Moreover, haploinsufficiency of Mic60 compromises brain glucose intake and oxygen consumption in mice, resembling human ME syndrome. We further discover that MIC60 protein expression declined significantly in human sME, implying that insufficient MIC60 may contribute for pathogenesis of human ME. Notably, systemic administration of antioxidant N-acetylcysteine largely reverses mitochondrial dysfunctions and metabolic disorders in haplo-insufficient Mic60 mice, also restores neurological abnormal symptom. These results reveal Mic60 is required in the maintenance of mitochondrial integrity and function, and likely a potential therapeutics target for mitochondrial encephalomyopathies.

Maternal and fetal predictors of anthropometry in the first year of life in offspring of women with GDM.

Gestational Diabetes Mellitus (GDM) carries an increased risk for adverse perinatal and longer-term cardiometabolic consequences in offspring. This study evaluated the utility of maternal anthropometric, metabolic and fetal (cord blood) parameters to predict offspring anthropometry up to 1 year in pregnancies with GDM. In this prospective analysis of the MySweetheart study, we included 193/211 women with GDM that were followed up to 1 year postpartum. Maternal predictors included anthropometric (pre-pregnancy BMI, gestational weight gain (GWG), weight and fat mass at the 1st GDM visit), and metabolic parameters (fasting insulin and glucose, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Quantitative insulin-sensitivity check index (QUICKI), HbA1c, triglycerides, and high-density lipoprotein (HDL) at the 1st visit and HbA1c at the end of pregnancy). Fetal predictors (N=46) comprised cord blood glucose and insulin, C-Peptide, HOMA-IR, triglycerides and HDL. Offspring outcomes were anthropometry at birth (weight/weight z-score, BMI, small and large for gestational age (SGA,LGA)), 6-8 weeks and 1 year (weight z-score, BMI/BMI z-score, and the sum of 4 skinfolds). In multivariate analyses, birth anthropometry (weight, weight z-score, BMI and/or LGA), was positively associated with cord blood HDL and HbA1c at the 1st GDM visit, and negatively with maternal QUICKI and HDL at the 1st GDM visit (all p ≤ 0.045). At 6-8 weeks, offspring BMI was positively associated with GWG and cord blood insulin, whereas the sum of skinfolds was negatively associated with HDL at the 1st GDM visit (all p ≤0.023). At 1 year, weight z-score, BMI, BMI z-score, and/or the sum of skinfolds were positively associated with pre-pregnancy BMI, maternal weight, and fat mass at the 1st GDM visit and 3rd trimester HbA1c (all p ≤ 0.043). BMI z-score and/or the sum of skinfolds were negatively associated with cord blood C-peptide, insulin and HOMA-IR (all p ≤0.041). Maternal anthropometric, metabolic, and fetal metabolic parameters independently affected offspring anthropometry during the 1st year of life in an age-dependent manner. These results show the complexity of pathophysiological mechanism for the developing offspring and could represent a base for future personalized follow-up of women with GDM and their offspring.

Infection and co-infection patterns of community-acquired pneumonia in patients of different ages in China from 2009 to 2020: a national surveillance study

Severe community-acquired pneumonia (SCAP) is associated with a substantial number of hospitalisations and deaths worldwide. Infection or co-infection patterns, along with their age dependence and clinical effects are poorly understood. We aimed to explore the causal and epidemiological characteristics by age, to better describe patterns of community-acquired pneumonia (CAP) and their association with severe disease. National surveillance of CAP was conducted through a network of hospitals in 30 provinces in China from 2009-20 inclusive. Patients with CAP were included if they had evidence of acute respiratory tract, had evidence of pneumonia by chest radiography, diagnosis of pneumonia within 24 h of hospital admission, and resided in the study catchment area. For the enrolled patients with CAP, nasopharyngeal and oral swabs were taken and tested for eight viral pathogens; and blood, urine, or expectorated sputum was tested for six bacterial pathogens. Clinical outcomes, including SCAP, were investigated with respect to age and patterns of infections or co-infections by performing binary logistic regression and multivariate analysis. Between January, 2009, and December, 2020, 18 807 patients with CAP (3771 [20·05%] with SCAP) were enrolled. For both children (aged ≤5 years) and older adults (aged >60 years), a higher overall rate of viral and bacterial infections, as well as viral-bacterial co-infections were seen in patients with SCAP than in patients with non-SCAP. For adults (aged 18-60 years), however, only a higher rate of bacterial-bacterial co-infection was observed. The most frequent pathogens associated with SCAP were respiratory syncytial virus (RSV; 21·30%) and Streptococcus pneumoniae (12·61%) among children, and influenza virus (10·94%) and Pseudomonas aeruginosa (15·37%) among older adults. Positive rates of detection of most of the tested pathogens decreased during 2020 compared with the 2009-19 period, except for RSV, P aeruginosa, and Klebsiella pneumoniae. Multivariate analyses showed SCAP was significantly associated with infection with human adenovirus, human rhinovirus, K pneumoniae, or co-infection of RSV and Haemophilus influenzae or RSV and Staphylococcus aureus in children and adolescents (aged <18 years), and significantly associated with infection with P aeruginosa, K pneumoniae, or S pneumoniae, or co-infection with P aeruginosa and K pneumoniae in adults (aged ≥18 years). Both prevalence and infection pattern of respiratory pathogens differed between patients with SCAP and patients with non-SCAP in an age-dependent manner. These findings suggest potential advantages to age-related strategies for vaccine schedules, as well as clinical diagnosis, treatment, and therapy. China Mega-Project on Infectious Disease Prevention and The National Natural Science Funds of China. For the Chinese translation of the abstract see Supplementary Materials section.

Leptin deficiency-caused behavioral change - A comparative analysis using EthoVision and DeepLabCut.

Obese rodents e.g., the leptin-deficient (ob/ob) mouse exhibit remarkable behavioral changes and are therefore ideal models for evaluating mental disorders resulting from obesity. In doing so, female as well as male ob/ob mice at 8, 24, and 40 weeks of age underwent two common behavioral tests, namely the Open Field test and Elevated Plus Maze, to investigate behavioral alteration in a sex- and age dependent manner. The accuracy of these tests is often dependent on the observer that can subjectively influence the data. To avoid this bias, mice were tracked with a video system. Video files were further analyzed by the compared use of two software, namely EthoVision (EV) and DeepLabCut (DLC). In DLC a Deep Learning application forms the basis for using artificial intelligence in behavioral research in the future, also with regard to the reduction of animal numbers. After no sex and partly also no age-related differences were found, comparison revealed that both software lead to almost identical results and are therefore similar in their basic outcomes, especially in the determination of velocity and total distance movement. Moreover, we observed additional benefits of DLC compared to EV as it enabled the interpretation of more complex behavior, such as rearing and leaning, in an automated manner. Based on the comparable results from both software, our study can serve as a starting point for investigating behavioral alterations in preclinical studies of obesity by using DLC to optimize and probably to predict behavioral observations in the future.

Effective differentiation of double negative thymocytes requires high fidelity replication of mitochondrial DNA in an age dependent manner.

One of the most proliferative periods for T cells occurs during their development in the thymus. Increased DNA replication can result in increased DNA mutations in the nuclear genome, but also in mitochondrial genomes. A high frequency of mitochondrial DNA mutations can lead to abnormal mitochondrial function and have negative implications on human health. Furthermore, aging is accompanied by an increase in such mutations through oxidative damage and replication errors. Increased mitochondrial DNA mutations cause loss of mitochondrial protein function, and decrease energy production, substrates, and metabolites. Here we have evaluated the effect of increased mitochondrial DNA mutations on T cell development in the thymus. Using mice carrying a mutant mitochondrial DNA polymerase γ (PolG) that causes increased mitochondrial DNA mutations, we show that high fidelity replication of mitochondrial DNA is pivotal for proper T cell development. Reducing the fidelity of mitochondrial DNA replication results in a premature age-dependent reduction in the total number of CD4/CD8 double negative and double positive thymocytes. Analysis of mitochondrial density in thymocyte subpopulations suggests that this may be due to reduced proliferation in specific double negative stages. Taken together, this work suggests that T cell development is regulated by the ability of mitochondria to faithfully replicate their DNA.

Spatial and Temporal Protein Modules Signatures Associated with Alzheimer Disease in 3xTg-AD Mice Are Restored by Early Ubiquinol Supplementation.

Despite its robust proteopathic nature, the spatiotemporal signature of disrupted protein modules in sporadic Alzheimer's disease (AD) brains remains poorly understood. This considered oxidative stress contributes to AD progression and early intervention with coenzyme Q10 or its reduced form, ubiquinol, delays the progression of the disease. Using MALDI-MSI and functional bioinformatic analysis, we have developed a protocol to express how deregulated protein modules arise from hippocampus and cortex in the AD mice model 3xTG-AD in an age-dependent manner. This strategy allowed us to identify which modules can be efficiently restored to a non-pathological condition by early intervention with ubiquinol. Indeed, an early deregulation of proteostasis-related protein modules, oxidative stress and metabolism has been observed in the hippocampus of 6-month mice (early AD) and the mirrored in cortical regions of 12-month mice (middle/late AD). This observation has been validated by IHC using mouse and human brain sections, suggesting that these protein modules are also affected in humans. The emergence of disrupted protein modules with AD signature can be prevented by early dietary intervention with ubiquinol in the 3xTG-AD mice model.