Aging under Pressure: The Roles of Reactive Oxygen and Nitrogen Species (RONS) Production and Aging Skeletal Muscle in Endothelial Function and Hypertension-From Biological Processes to Potential Interventions

Negative association between triglyceride glucose index and BMI-adjusted skeletal muscle mass index in hypertensive adults

BACKGROUND

The triglyceride glucose (TyG) index, an indicator of insulin resistance, is often associated with adverse outcomes in various cardiovascular diseases, while hypertension is associated with an increased risk of cardiovascular diseases. As the loss of muscle mass in people with hypertension is poorly understood, the current study aimed to explore the relationship between TyG index and muscle mass in hypertensive population.

METHODS

We analyzed data from hypertensive adult participants in the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018. The TyG index and body mass index (BMI)-adjusted skeletal muscle mass index (SMI) were calculated and the relationship between the two was evaluated using multivariable linear regression and restricted cubic spline (RCS) regression models.

RESULTS

A total of 1633 participants in the dataset were included for the final analysis. In the multivariable regression analysis, the adjusted β of SMI with a 95% confidence interval (CI) for the highest TyG index quartile was - 5.27 (- 9.79 to - 0.75), compared with the lowest quartile. A negative linear relationship between TyG index and SMI was plotted by RCS regression (nonlinear P = 0.128). Stratified models of non-smoking women of different ages also demonstrated that SMI decreased as TyG index increased (all P for trend < 0.05).

CONCLUSION

This linear and negative correlation between TyG index and SMI in hypertensive patients suggests that insulin resistance adversely affects muscle mass.

Hypertension and cellular senescence

Essential or primary hypertension is a wordwide health problem. Elevated blood pressure (BP) is closely associated not only with increased chronological aging but also with biological aging. There are various common pathways that play a role in cellular aging and BP regulation. These include but not limited to inflammation, oxidative stress, mitochondrial dysfunction, air pollution, decreased klotho activity increased renin angiotensin system activation, gut dysbiosis etc. It has already been shown that some anti-hypertensive drugs have anti-senescent actions and some senolytic drugs have BP lowering effects. In this review, we have summarized the common mechanisms underlying cellular senescence and HT and their relationships. We further reviewed the effect of various antihypertensive medications on cellular senescence and suggest further issues to be studied.

The Disposition of Bioactive Compounds from Fruit Waste, Their Extraction, and Analysis Using Novel Technologies: A Review

Fruit waste contains several bioactive components such as polyphenols, polysaccharides, and numerous other phytochemicals, including pigments. Furthermore, new financial opportunities are created by using fruit ‘leftovers’ as a basis for bioactivities that may serve as new foods or food ingredients, strengthening the circular economy’s properties. From a technical standpoint, organic phenolic substances have become more appealing to industry, in addition to their application as nutritional supplements or functional meals. Several extraction methods for recovering phenolic compounds from fruit waste have already been published, most of which involve using different organic solvents. However, there is a growing demand for eco-friendly and sustainable techniques that result in phenolic-rich extracts with little ecological impact. Utilizing these new and advanced green extraction techniques will reduce the global crisis caused by fruit waste management. Using modern techniques, fruit residue is degraded to sub-zero scales, yielding bio-based commodities such as bioactive elements. This review highlights the most favorable and creative methods of separating bioactive materials from fruit residue. Extraction techniques based on environmentally friendly technologies such as bioreactors, enzyme-assisted extraction, ultrasound-assisted extraction, and their combination are specifically covered.

KLF4 prevented angiotensin II-induced smooth muscle cell senescence by enhancing autophagic activity

BACKGROUND

Vascular aging is an important risk factor for various cardiovascular diseases. Transcription factor krüppel-like factor 4 (KLF4) could regulate the phenotypic transformation of the vascular smooth muscle cell (VSMC) in the pathogenesis of aortic diseases. The present study aimed to explore the role and mechanism of KLF4 in angiotensin II (Ang II)-induced VSMC senescence.

METHODS

The VSMC senescence mouse model was induced by sustained release of Ang II (1.0 μg/kg/min) for 4 weeks. The premature senescent VSMCs were induced by Ang II (0.1 μmol/L) for 72 h. Cellular senescence was measured by senescence-associated β-galactosidase (SA-β-gal) activity and p53/p16 expression. The autophagic activity was evaluated by autophagic flux and autophagic marker expression.

RESULTS

The expression of KLF4 was extremely increased in abdominal aorta tissues after 1-week Ang II stimulation (p < .01) but began to decrease in later periods. Decreased expression of KLF4 was also detected in premature senescent VSMCs. Overexpression of KLF4 could enhance the antisenescence ability of VSMCs. Significantly decreased amounts of SA-β-gal-positive cells and lower p53/p16 expression were detected in KLF4-overexpressing VSMCs (p < .01). Next, telomerase reverse transcriptase (TERT) was identified as a direct downstream target of KLF4 in VSMCs. Overexpression of KLF4 in VSMCs prevented the decreased expression of TERT under Ang II stimulation condition, which could in turn, contribute to the enhanced autophagic activity, and ultimately to the improved antisenescence ability of VSMCs.

CONCLUSIONS

Our results demonstrated that overexpression of KLF4 prevented Ang II-induced VSMC senescence by promoting TERT-mediated autophagy. These findings provided novel potential targets for the prevention and therapy of vascular aging.