To increase the efficiency of interpretation of mast cell's contribution to the state of a specific tissue microenvironment, it is necessary to detail the molecular composition of their secretome and analyze the pathways of degranulation. Developed method of combining immunomorphological and histochemical staining protocols contributes to the most objective detection of the integral level of tryptase expression in the intraorgan population of the skin mast cells. Novel technique for tryptase detection expands the possibilities of morphological analysis, provides researchers with additional data on the structure of the mast cell population and helps visualize the processing and cytological features and structural targets of tryptase during the development of adaptive and pathological reactions. Objective determination of the tryptase profile for organ-specific mast cell populations is in great demand in clinical practice for the interpretation of pathological processes, including inflammation and oncogenesis.

Hydrogen has been shown to exhibit selective antioxidant properties against hydroxyl radicals, and exerts antioxidant and anti-inflammatory effects. The monocrotaline-induced model of pulmonary hypertension is suitable for studying substances with antioxidant activity because oxidative stress is induced by monocrotaline. On day 1, male Wistar rats were subcutaneously injected with a water–alcohol solution of monocrotaline or a control with an only water–alcohol solution. One group of monocrotaline-injected animals was placed in a plastic box that was constantly ventilated with atmospheric air containing 4% of molecular hydrogen, and the two groups of rats, injected with monocrotaline or vehicle, were placed in boxes ventilated with atmospheric air. After 21 days, hemodynamic parameters were measured under urethane narcosis. The results showed that, although hydrogen inhalation had no effect on the main markers of pulmonary hypertension induced by monocrotaline injection, there was a reduction in systemic blood pressure due to its systolic component, and a decrease in TGF-β expression, as well as a reduction in tryptase-containing mast cells.

Both apoptotic and inflammatory caspases play a significant role in developing and maintaining an organism’s homeostasis. Recently, various studies have described various cross-interactions among various caspases. For instance, interleukin-1β activation is initiated by caspase-1 and caspase-8. Programmed cell death is launched not exclusively by internal and external factors to serve as a foundation for physiological development and realization of cellular and organism functions. The caspases involved in this process provide a complicated function related to cell homeostasis regulation. Caspases also participate in adaptation processes associated with changing environmental conditions, including microgravity. Phenotypical analysis of knockdown laboratory animals can reveal the physiological functions of caspases, giving preference to mice. For instance, this approach allows us to determine the role of caspases in the pathogenesis of different pathologic conditions, such as malignancies and autoimmune and infectious diseases. Caspases are considered by a wide spectrum of authors as therapeutic targets. In general, the topic of caspases and their functions is very broad. In this review, we only discuss some aspects of the impact of caspases on various types of cell death.

MicroRNA-26a (miRNA-26a) is a critical regulator of molecular processes, impacting the pathogenesis of numerous diseases due to its ability to modulate gene expression across various organ systems and tissues. This review examines the mechanisms of miRNA-26a action and its therapeutic potential, with a particular focus on its role in heart failure (HF). In HF, miRNA-26a exerts cardioprotective effects, suppressing cardiomyocyte hypertrophy, fibrosis, and electrical remodeling by targeting GATA4, CTGF, and KCNJ2. Reduced miRNA-26a expression correlates with HF progression, underscoring its role as a biomarker and therapeutic target. Interactions with other microRNAs, such as miR-1 and miR-133, amplify its effects. Beyond cardiology, miRNA-26a modulates oncological processes, e.g., inhibiting proliferation in colorectal cancer, inflammation in inflammatory bowel disease, and metabolic and neurodegenerative disorders by targeting EZH2, PTEN, and VEGF. Preclinical studies highlight the promise of miRNA-26a-mimics for HF treatment, though challenges in delivery and dosing warrant further exploration. This review article, with an emphasis on cardiovascular pathology, acknowledges the high prevalence and critical significance of HF in morbidity and mortality, advocating for research into combined strategies with other miRNAs. Overall, miRNA-26a holds significant potential for personalized medicine, offering improved outcomes for patients with HF and other related pathologies.

Introduction: The human body is exposed to numerous chemical and biological environmental factors. Post-exposure allergic reactions are becoming increasingly common. Interacting substances enhance each other’s health effects and aggravate allergy symptoms. Registration of a high pollen count resulting from a gradual increase in ambient temperatures leads to disappointing forecasts of a high prevalence of allergic rhinitis (hay fever). Evaluation of public health monitoring data on drinking water and food quality has revealed the significance of such pollutants as nitrates and nitrites. The interaction between pollen and nitrates has not been studied although it is of interest in terms of potential health effects of combined exposures. Objectives: To evaluate morphological changes in the quantitative composition of mast cells using an aqueous solution of molecular hydrogen in an experimental model of hay fever aggravated by exposure to chemical agents. Methods: Male Wistar rats were selected for experimental modeling of allergic rhinitis and 34 groups of six animals each were exposed to pollen and chemical agents during 55 days. To assess morphological changes in the nasal respiratory mucosa, we stained tissues with Giemsa solution and also applied a combined staining technique (Patent No. 2781558 dated October 13, 2022). Study limitations: Groups for comparison of methods of administration of the aqueous solution of molecular hydrogen against the saline solution were not included. Results: The cell morphology analysis revealed quantitative and qualitative changes in the animal groups with single and combined exposure to pollen and chemical agents and confirmed the therapeutic and prophylactic effect of the aqueous solution enriched with molecular hydrogen. Conclusion: The combined exposure to pollen allergens and nitrates and/or nitrites induces significant mast cell activation compared to control and single exposure groups. Therapeutic and preventive effects of molecular hydrogen down-regulate mast cell degranulation.