Vol 65, No 6 (2023)

Aging and associated diseases are an acute problem of modern biology and medicine. Although aging cannot be prevented at present, its impact on the lifespan and health of the elderly can potentially be minimized by interventions aimed at returning these cellular processes to normal functioning. The ongoing search for ways to rejuvenate and improve the regenerative capacity of cells led to the discovery of partial reprogramming in 2016. Partial reprogramming is based on the short-term expression of reprogramming factors (Oct4, Sox2, Klf4 and c-Myc). As a result, the young epigenetic signature of aging cells is restored. The efficacy of the method has been shown in both in vitro and in vivo systems. In this review we discuss the main successes of partial reprogramming, as well as the problems and unresolved issues faced by the researchers. Separately, we focus on the data on molecular changes during partial reprogramming. The method of partial reprogramming provides a wide range of opportunities for fundamental research of aging and rejuvenation. Further work in this direction can lead to the development of therapeutic strategies to alleviate age-related diseases and thus improve health and longevity.

The article discusses the metabolism of niacin, also known as vitamin B3 or PP, and the mechanisms of its receptor-induced functions in the human body. Niacin exists as a several molecular compounds that act as the nicotinamide coenzymes precursors. These coenzymes being electron donors or acceptors in redox reactions catalyzed by various enzymes play a crucial role in metabolism. Maintenance of the intracellular niacin pool is vital not only for redox metabolism, but also for the NAD-dependent pathways functioning. At the same time, pathophysiological situations and changes in enzyme activity can affect the necessity for various niacin forms. In addition to indirect effects via nicotinamide coenzymes, it also has a number of direct effects, including anti-lipolytic, vasodilatory, and neuroprotective functions, the exact mechanism of which has not been studied fully up to date. Overall, niacin plays a vital role in maintaining the efficient cell functioning, and further study of its influence on various physiological aspects, including the gut microbiome and epigenetic regulation, could lead to new discoveries and treatments for various diseases.

The extracellular matrix (ECM), the main component of the extracellular space, mediates signaling between cells and controls the key cell functions—proliferation, differentiation, and migration. The relevance of studying ECM is due to a wide range of its biological properties that can be applied in regenerative medicine and bioengineering. Cell-derived decellularized ECM (dECM) is used to study ECM as a regulator of the cell functional activity, as well as to mimic their tissue-specific microenvironment. Here, we hypothesized that dECM deposited by Wharton’s jelly-derived MSCs modulates the senescence phenotype of endometrial MSCs (eMSCs) acquired in response to oxidative stress. This aspect of ECM functioning in the context of eMSCs has so far remained unexplored. A comparative study of prolonged H₂O₂-induced senescence of eMSCs exposed to both dECM and cultured plastic showed that dECM may effectively downregulate the main senescence markers. Our findings suggest that ECM is able to partially reverse (retard) the eMSCs premature senescence.

Preterm birth has a pronounced effect on all body systems, including the cardiovascular system, which undergoes significant adaptive changes in the early postnatal period of ontogenesis. A comprehensive understanding of the consequences of preterm birth is essential to ensure early prevention, detection and treatment of long-term adverse health effects. The aim of our study was to evaluate the effect of preterm birth on the structure of the wall of the ascending aorta in preterm rats. The paper presents the results of histological and morphometric analysis of ascending aorta wall in Wistar rats born on the 21st and 21.5 days of pregnancy (the total gestation period is 22 days). In ascending aorta wall of preterm born rats, signs of elastolysis and a violation of the parallelism of the elastic fenestrated membranes are found. It has been shown that preterm birth leads to a decrease in the specific volume of elastic fibers and an increase in collagen fibers in the meddle shell of ascending aorta wall in prematurely born rats.