Genomic stability and telomere regulation in skeletal muscle tissue

Aqueous Extract of Wolfberry Alleviates Aging-Related Skeletal Muscle Dysfunction by Modulating PRRs Signaling Pathways and Enhancing DNA Repair

Aging can lead to a series of degenerative changes in skeletal muscle, which would negatively impact physical activity and the quality of life of the elderly. Wolfberry contains numerous bioactive substances. It's vital to further explore the mechanisms underlying its healthy effects on skeletal muscle function during aging progress. This study discusses the benefits and mechanisms of aqueous extract of wolfberry (AEW) to protect skeletal muscle from aging-related persistent DNA damage based on its anti-inflammatory activity. It is found that AEW improves muscle mass, strength, and endurance, modulates the expression of Atrogin-1, MyH, and MuRF-1, and decreases oxidative stress and inflammation levels in aging mice, which is consistent with the in vitro results. Mechanistically, AEW inhibits the pattern recognition receptors (PRRs) pathway induced by inflammatory gene activation, suggesting its potential in response to DNA damage. AEW is also observed to mitigate chromatin decompaction. Network pharmacology is conducted to analyze the potential targets of AEW in promoting DNA repair. In conclusion, the study shows the anti-aging effects of AEW on skeletal muscle by promoting DNA repair and reducing the transcriptional activity of inflammatory factors. AEW intake may become a potential strategy for strengthening skeletal muscle function in the elderly.

Low-power infrared laser modulates mRNA levels from genes of base excision repair and genomic stabilization in heart tissue from an experimental model of acute lung injury

The aim of this study was to evaluate photobiomodulation effects on mRNA relative levels from genes of base excision repair and genomic stabilization in heart tissue from an experimental model of acute lung injury by sepsis. For experimental procedure, animals were randomly assigned to six main groups: (1) control group was animals treated with intraperitoneal saline solution; (2) LASER-10 was animals treated with intraperitoneal saline solution and exposed to an infrared laser at 10 J cm^-2; (3) LASER-20 was animals treated with intraperitoneal saline solution and exposed to an infrared laser at 20 J cm^-2; (4) acute lung injury (ALI) was animals treated with intraperitoneal LPS (10 mg kg^-1); (5) ALI-LASER10 was animals treated with intraperitoneal LPS (10 mg kg^-1) and, after 4 h, exposed to an infrared laser at 10 J cm^-2 and (6) ALI-LASER20 was animals treated with intraperitoneal LPS (10 mg kg^-1) and, after 4 h, exposed to an infrared laser at 20 J cm^-2. Irradiation was performed only once and animal euthanasias for analysis of mRNA relative levels by RT-qPCR. Our results showed that there was a reduction of mRNA relative levels from ATM gene and an increase of mRNA relative levels from P53 gene in the heart of animals with ALI when compared to the control group. In addition, there was an increase of mRNA relative levels from OGG1 and APE1 gene in hearts from animals with ALI when compared to the control group. After irradiation, an increase of mRNA relative levels from ATM and OGG1 gene was observed at 20 J cm^-2. In conclusion, low-power laser modulates the mRNA relative levels from genes of base excision repair and genomic stabilization in the experimental model of acute lung injury evaluated.

Long-lived post-mitotic cell aging: is a telomere clock at play?

Senescence is a cellular response to stress for both dividing and post-mitotic cells. Noteworthy, long-lived post-mitotic cells (collectively named LLPMCs), which can live for decades in the organism, can exhibit a distinct type of cellular aging characterized by a progressive functional decline not associated to an overt senescence phenotype. The age-related drivers of senescence and aging in LLPMCs remain largely unknown. There is evidence that an increased production of reactive oxygen species (ROS) due to dysfunctional mitochondria, coupled with an inherent inability of cellular-degradation mechanisms to remove damaged molecules, is responsible for senescence and aging in LLPMC. Although telomeric DNA shortening, by nature linked to cell division, is generally not considered as a driver of LLPMC aging and senescence, we discuss recent reports revealing the existence of age-related telomere changes in LLPMC. These findings reveal unexpected roles for telomeres in LLPMC function and invite us to consider the hypothesis of a complex telomere clock involved in both dividing and non-dividing cell aging.

Chromosomal Processes in Mind-Body Medicine: Chronic Stress, Cell Aging, and Telomere Length

Stress affects cellular aging and inflammatory and chromosomal processes, including telomere length, thereby potentially compromising health and facilitating disease onset and progression. Stress-related diseases and strategies to manage stress usually require integrative or behavioral therapeutic approaches that also operate on cellular levels. Mind-body medicine (MBM) uses the interaction between the mind, body, behavior, and the environment to correct physical and psychological malfunctions, thus ameliorating disease states and improving health. The relaxation response (RR) is a physiological opponent of stress and the stress response (SR) (i.e., fight-or-flight response), also invoking molecular anti-stress processes. Techniques that elicit the RR are at the core of practically all MBM interventions. We surmise that these techniques can also affect chromosomal and telomere processes, molecular aging, and the modulation of inflammatory states on cellular levels.