Sirtuin 1 (Sirt1) has a range of molecular functions and has emerged as an important protein in aging and metabolic regulations. Studies have reported a correlation between disturbance of Sirt1 activity and the onset of aging‑ or obesity‑associated diseases, including diabetes, cardiovascular disease and neurodegenerative disorders. However, a systematic investigation to examine the changes of Sirt1 expression in a wide range of ages and to what degree it changes has yet to be performed. To assess the effects of aging on the changes of Sirt1 expression, an in vivo model of aging, senescence-accelerated mouse prone 8 (SAM‑P8) and a control counterpart strain, senescence-accelerated mouse resistant 1 (SAM‑R1) was used. The mRNA and protein expression levels of Sirt1 were detected in four different tissues, including brain, liver, skeletal muscle and white adipose tissue, in both strains at different ages (1-, 4-, 8- and 12-month old). Therefore, different life stages, including young age prior to maturation, adult, middle age and old age were examined. The results identified that Sirt1 expression declined with age at the transcriptional and translational levels in the brain, liver, skeletal muscle and white adipose tissue in SAM-P8 and SAM‑R1. The Sirt1 expression level was lower in SAM-P8 than in SAM‑R1, particularly at old age. Among the four tissues, it was most significantly reduced in the brain.

The risk of developing neurodegenerative disorders such as Alzheimer’s disease (AD) increases dramatically with age. Understanding the underlying mechanisms of brain aging is crucial for developing preventative and/or therapeutic approaches for age-associated neurological diseases. Recently, it has been suggested that epigenetic factors, such as histone modifications, maybe be involved in brain aging and age-related neurodegenerations. In this study, we investigated 14 histone modifications in brains of a cohort of young (3 months), old (22 months), and old age-matched dietary restricted (DR) and rapamycin treated BALB/c mice. Results showed that 7 out of all measured histone markers were changed drastically with age. Intriguingly, histone methylations in brain tissues, including H3K27me3, H3R2me2, H3K79me3 and H4K20me2 tend to disappear with age but can be partially restored by both DR and rapamycin treatment. However, both DR and rapamycin treatment also have a significant impact on several other histone modifications such as H3K27ac, H4K16ac, H4R3me2, and H3K56ac, which do not change as animal ages. This study provides the first evidence that a broad spectrum of histone modifications may be involved in brain aging. Besides, this study suggests that both DR and rapamycin may slow aging process in mouse brain via these underlying epigenetic mechanisms.

Body posture is a fundamental indicator for assessing health and quality of life, especially for elderly people. Deciphering the changes in body posture occurring with age is a current topic in the field of geriatrics. The aims of this study were to assess the parameters of standing body posture in the global sagittal plane and to determine the dynamics of changes in standing body posture occurring with age and differences between men and women. The measurements were performed on 226 individuals between the ages of 20 to 89 with a new photogrammetry, via which we assessed five postural angles - neck, thorax, waist, hip and knee. The data were analyzed with t-test, one-way ANOVA, linear regression model and generalized additive model. Among these segments studied here, neck changed most, while the middle segments of the body, waist and hip, were relative stable. Significant differences between men and women were found with respect to the angles of neck, thorax and hip. Three of the five postural angles were significantly influenced with aging, including increasing cervical lordosis, thoracic kyphosis and knee flexion, starting from no older than around 50 yrs. showed by fitting curve derived with generalized additive model. These changes were more marked among women. Besides, this study highlights the effects of age and gender on the complex interrelation between adjacent body segments in standing. The presented results showed changes in the parameters describing body posture throughout consecutive ages and emphasized that for an individualized functional analysis, it is essential to consider age-and gender-specific changes in the neck, thorax and knee. This paper presents useful externally generalizable information not only for clinical purposes but also to inform further research on larger numbers of subjects.

Aim. Ginkgolide B is a Ginkgo biloba leaf extract that has been identified as a natural platelet‐activating factor receptor (PAFR) antagonist. We investigated the effect of ginkgolide B on high glucose‐induced TLR4 activation in human umbilical vein endothelial cells (HUVECs). Methods. Protein expression was analyzed by immunoblotting. Small‐interfering RNA (siRNA) was used to knock down PAFR and TLR4 expression. Results. Ginkgolide B suppressed the expression of TLR4 and MyD88 that was induced by high glucose. Ginkgolide B also reduced the levels of platelet endothelial cell adhesion molecule‐1, interleukin‐6, and monocyte chemotactic protein 1. Further, we examined the association between PAFR and TLR4 by coimmunoprecipitation. The result showed that high glucose treatment caused the binding of PAFR and TLR4, whereas ginkgolide B abolished this binding. The functional analysis indicated that PAFR siRNA treatment reduced TLR4 expression, and TLR4 siRNA treatment decreased PAFR expression in high glucose‐treated HUVECs, further supporting the coimmunoprecipitation data. Ginkgolide B inhibited the phosphorylation of Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) and p38 mitogen‐activated protein kinase (MAPK). Conclusion. Ginkgolide B exerted protective effects by inhibiting the TLR4‐mediated inflammatory response in high glucose‐treated endothelial cells. The mechanism of action of ginkgolide B might be associated with inhibition of the JAK2/STAT3 and p38 MAPK phosphorylation.

The associations of sarcopenia with adverse health status have highlighted the importance of sarcopenia research and intervention. This study was designed to analyze the characteristics of aging-related differences in appendicular skeletal muscle mass (ASM), handgrip strength (HS), gait speed (GS) and their associated factors in older Chinese, in order to generate guidance for sarcopenia intervention in this population. Population-based cross-sectional study. The criteria proposed by Asian Working Group for Sarcopenia were used to define low ASM, HS, and GS. The time required for five repeated chair stands (RCS) was also measured to evaluate physical performance. The differences of continuous variables were compared using one-way ANOVA tests and the Pearson correlation was used to analyze the relationship of each measurement adjusted by gender and age. Stepwise logistic regression was used to determine associated factors of low HS and low physical performance. The data were analyzed in a total of 218 younger adults (aged 20–59, 76 males, 142 females) and 461 older adults (≥60 year, 207 males and 254 females). There were significant differences among age groups for HS, GS, and RCS while females were found to have significantly lower HS and GS values. ASM was significantly correlated with HS but not with other measures. Correlations among HS and GS, RCS were influenced by age differences. In the older group, unstructured daily routine (OR = 2.77) was associated with the risk of low GS, while physical exercise (OR = 0.27), and engaging in hobbies (OR = 0.11) were associated with faster GS. Co-morbidity (OR = 1.99) was associated with the risk of reduced performance of RCS, while engaging in hobbies was associated with faster RCS performance (OR = 0.35). Muscle strength and physical performance varied with aging in older Chinese. Measures of GS, HS, and RCS provide a readily available and effective method for assessing the risk of functional mobility decline. Maintaining a healthy life style and physical activity throughout life is beneficial for older people to improve their physical performance, especially in the early stages of aging.

Aim. Resveratrol is a natural plant polyphenol. The present study investigated the effects of resveratrol on the Toll-like receptor 4- (TLR4-) mediated expression and secretion of matrix metalloproteinases (MMPs) in oxidized low-density lipoprotein- (ox-LDL-) treated human umbilical vein endothelial cells (HUVECs). Methods. Protein expression was analyzed by immunoblotting. The secretion of MMPs was measured by an enzyme-linked immunosorbent assay. The animal experiments were performed with and without resveratrol treatment in high-fat chow-fed mice. Results. Resveratrol inhibited the expression of TLR4, MMP3, and MMP9 in ox-LDL- and lipopolysaccharide- (LPS-) treated HUVECs. Resveratrol reduced the secretion of MMP3 and MMP9 that was induced by ox-LDL and LPS. The TLR4 inhibitor CLI-095 similarly suppressed the expression and secretion of MMP3 and MMP9 in ox-LDL- and LPS-treated HUVECs. Resveratrol attenuated the phosphorylation of the transcription factors nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) that was induced by ox-LDL and LPS. Resveratrol recovered Sirt1 expression. In the animal experiments, resveratrol decreased TLR4 expression in the aorta, MMP9 levels in plasma, and vascular structural changes in high-fat chow-fed mice, with no significant effect on plasma MMP3 levels. Conclusion. Resveratrol inhibited the TLR4-mediated expression and secretion of MMP3 and MMP9 in ox-LDL-treated HUVECs. The mechanism of action of resveratrol may be associated with the suppression of NF-κB and STAT3 phosphorylation and restoration of Sirt1 expression. Resveratrol exerts protective effects against vascular structural changes in high-fat chow-fed mice.