Pays tribute to the recently deceased poet and publisher of Caveman Press. Includes his poem, 'They're keeping tabs'. Source: National Library of New Zealand Te Puna Matauranga o Aotearoa, licensed ...by the Department of Internal Affairs for re-use under the Creative Commons Attribution 3.0 New Zealand Licence.
Age-related chronic low-grade inflammatory profile (CLIP) has been recognized as an important causative factor for sarcopenia. Here, we report the recent evidence concerning CLIP and sarcopenia.
...Twenty-one studies were included (12 observational, five interventional studies and four randomized controlled trials). Observational studies strengthen the association between CLIP and sarcopenia in cross-sectional and longitudinal designs. Interleukin (IL)-6 and tumour necrosis factor-α are the most reported inflammatory parameters. Biopsy studies confirm the role of oxidative mechanisms, protein kinase B and nuclear factor kappa-light-chain-enhancer of activated B cells pathways and implicate stress response mechanisms and heat shock protein. Adipose tissue as source of inflammatory cytokines remains unclear and correction for fat mass is advisable in new research. Exercise interventions (both aerobic and resistance training) demonstrate beneficial effects on CLIP even in the absence of decreases in weight, BMI or fat mass. IL-6 is also released during exercise, in hormone-like fashion unrelated to inflammation, and exercise-induced IL-6 changes require careful interpretation. Soy supplementation in one study showed no influence on CLIP and no recent pharmacological trials were retrieved.
Associations between CLIP and sarcopenia are observed quite consistently and underlying mechanisms become apparent. Exercise remains the mainstay intervention to lower CLIP and counter sarcopenia. More research is warranted to unravel the exact dose-response relationship.
Summary
Chronic caloric restriction (CR) and rapamycin inhibit the mechanistic target of rapamycin (mTOR) signaling, thereby regulating metabolism and suppressing protein synthesis. Caloric ...restriction or rapamycin extends murine lifespan and ameliorates many aging‐associated disorders; however, the beneficial effects of shorter treatment on cardiac aging are not as well understood. Using a recently developed deuterated‐leucine labeling method, we investigated the effect of short‐term (10 weeks) CR or rapamycin on the proteomics turnover and remodeling of the aging mouse heart. Functionally, we observed that short‐term CR and rapamycin both reversed the pre‐existing age‐dependent cardiac hypertrophy and diastolic dysfunction. There was no significant change in the cardiac global proteome (823 proteins) turnover with age, with a median half‐life 9.1 days in the 5‐month‐old hearts and 8.8 days in the 27‐month‐old hearts. However, proteome half‐lives of old hearts significantly increased after short‐term CR (30%) or rapamycin (12%). This was accompanied by attenuation of age‐dependent protein oxidative damage and ubiquitination. Quantitative proteomics and pathway analysis revealed an age‐dependent decreased abundance of proteins involved in mitochondrial function, electron transport chain, citric acid cycle, and fatty acid metabolism as well as increased abundance of proteins involved in glycolysis and oxidative stress response. This age‐dependent cardiac proteome remodeling was significantly reversed by short‐term CR or rapamycin, demonstrating a concordance with the beneficial effect on cardiac physiology. The metabolic shift induced by rapamycin was confirmed by metabolomic analysis.
Aging is associated with a chronic low‐grade inflammatory status that contributes to chronic diseases such as age‐related muscle wasting, kidney disease, and diabetes mellitus. Since advanced ...glycation end products (AGEs) are known to be proinflammatory, this systematic review examined the relation between the dietary intake of AGEs and inflammatory processes. The PubMed and Web of Science databases were screened systematically. Seventeen relevant studies in humans or animals were included. The intervention studies in humans showed mainly a decrease in inflammation in subjects on a low‐AGE diet, while an increase in inflammation in subjects on a high‐AGE diet was less apparent. About half of the observational studies found a relationship between inflammatory processes and AGEs in food. When the results are considered together, the dietary intake of AGEs appears to be related to inflammatory status and the level of circulating AGEs. Moreover, limiting AGE intake may lead to a decrease in inflammation and chronic diseases related to inflammatory status. Most of the trials were conducted in patients with chronic kidney disease or diabetes, and thus additional studies in healthy individuals are needed. Further investigation is needed to elucidate the effects of lifetime exposure of dietary AGEs on aging and health.
We investigated the protective effects of mitochondrial-targeted antioxidant and protective peptides, Szeto-Schiller (SS) 31 and SS20, on cardiac function, proteomic remodeling, and signaling ...pathways.
We applied an improved label-free shotgun proteomics approach to evaluate the global proteomics changes in transverse aortic constriction (TAC)-induced heart failure and the associated signaling pathway changes using ingenuity pathway analysis. We found that 538 proteins significantly changed after TAC, which mapped to 53 pathways. The top pathways were in the categories of actin cytoskeleton, mitochondrial function, intermediate metabolism, glycolysis/gluconeogenesis, and citrate cycle. Concomitant treatment with SS31 ameliorated the congestive heart failure phenotypes and mitochondrial damage induced by TAC, in parallel with global attenuation of mitochondrial proteome changes, with an average of 84% protection of mitochondrial and 69% of nonmitochondrial protein changes. This included significant amelioration of all the ingenuity pathway analysis noted above. SS20 had only modest effects on heart failure and this tracked with only partial attenuation of global proteomics changes; furthermore, actin cytoskeleton pathways were significantly protected in SS20, whereas mitochondrial and metabolic pathways essentially were not.
This study elucidates the signaling pathways significantly changed in pressure-overload-induced heart failure. The global attenuation of TAC-induced proteomic alterations by the mitochondrial-targeted peptide SS31 suggests that perturbed mitochondrial function may be an upstream signal to many of the pathway alterations in TAC and supports the potential clinical application of mitochondrial-targeted peptide drugs for the treatment heart failure.
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