Using chemiluminescence to determine whole blood antioxidant capacity in rheumatoid arthritis and Parkinson's disease patients

Evolving insights into erythrocytes in synucleinopathies

Synucleinopathies, including Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB), are characterized by neuronal loss accompanied by α-synuclein (α-syn) accumulation in the brain. While research conventionally focused on brain pathology, there is growing interest in peripheral alterations. Erythrocytes, which are rich in α-syn, have emerged as a compelling site for synucleinopathies-related alterations. Erythrocyte-derived extracellular vesicles (EVs), containing pathological α-syn species, can traverse the blood-brain barrier (BBB) under certain conditions and the gastrointestinal tract, where α-syn and gut microbiota interact extensively. This review explores the accumulating evidence of erythrocyte involvement in synucleinopathies, as well as their potential in disease pathogenesis and diagnosis. Given their unique properties, erythrocytes and erythrocyte-derived EVs may also serve as an ideal therapeutic platform for treating synucleinopathies and beyond.

Nucleic acid aptamer-based biosensors and their application in thrombin analysis

Thrombin is a multifunctional serine protease that plays an important role in coagulation and anticoagulation processes. Aptamers have been widely applied in biosensors due to their high specificity, low cost and good biocompatibility. This review summarizes recent advances in thrombin quantification using aptamer-based biosensors. The primary focus is optical sensors and electrochemical sensors, along with their applications in thrombin analysis and disease diagnosis.

The Effect of Progestins on Cytokine Production in the Peripheral Blood Mononuclear Cells of Menopausal Women and Their Luminol-Dependent Chemiluminescence

Steroid hormones are the key regulators of inflammatory and autoimmune processes. The role of steroid hormones is mostly inhibitory in these processes. The expression of IL-6, TNFα, and IL-1β, as markers of inflammation, and TGFβ, as a marker of fibrosis, could be useful tools to predict the response of an individual's immune system to the different progestins suitable for the treatment of menopausal inflammatory disorders, including endometriosis. In this study, the progestins P4 and MPA, as well as the novel progestin gestobutanoyl (GB), which possess potent anti-inflammatory properties towards endometriosis, were studied at a fixed concentration of 10 µM. Their influence on the production of the above cytokines in PHA-stimulated peripheral blood mononuclear cells (PBMCs) during 24 h incubation was evaluated by ELISA. It was found that synthetic progestins stimulated the production of IL-1β, IL-6, and TNFα and inhibited TGFβ production, while P4 inhibited IL-6 (33% inhibition) and did not influence TGFβ production. In the MTT-viability test, P4 also decreased PHA-stimulated PBMC viability by 28% during 24 h incubation, but MPA and GB did not have any inhibitory or stimulatory effects. The luminol-dependent chemiluminescence (LDC) assay revealed the anti-inflammatory and antioxidant properties of all the tested progestins, as well as some other steroid hormones and their antagonists: cortisol, dexamethasone, testosterone, estradiol, cyproterone, and tamoxifen. Of these, tamoxifen showed the most pronounced effect on the oxidation capacity of PBMC but not on that of dexamethasone, as was expected. Collectively, these data demonstrate that PBMCs from menopausal women respond differently to P4 and synthetic progestins, most likely due to distinct actions via various steroid receptors. It is not only the progestin affinity to nuclear progesterone receptors (PR), androgen receptors, glucocorticoid receptors, or estrogen receptors that is important for the immune response, but also the membrane PR or other nongenomic structures in immune cells.

Chemiluminescence Detection in the Study of Free-Radical Reactions. Part 1

The present review, consisting of two parts, considers the application of the chemiluminescence detection method in evaluating free radical reactions in biological model systems. The first part presents a classification of experimental biological model systems. Evidence favoring the use of chemiluminescence detection in the study of free radical reactions, along with similar methods of registering electromagnetic radiation as electron paramagnetic resonance, spectrophotometry, detection of infrared radiation (IR spectrometry), and chemical methods for assessing the end products of free radical reactions, is shown. Chemiluminescence accompanying free radical reactions involving lipids has been the extensively studied reaction. These reactions are one of the key causes of cell death by either apoptosis (activation of the cytochrome c complex with cardiolipin) or ferroptosis (induced by free ferrous ions). The concept of chemiluminescence quantum yield is also discussed in this article. The second part, which is to be published in the next issue, analyzes the application of chemiluminescence detection using luminescent additives that are called activators, a.k.a. chemiluminescence enhancers, and enhance the emission through the triplet-singlet transfer of electron excitation energy from radical reaction products, followed by light emission with a high quantum yield.

Coelenterazine-Dependent Luciferases as a Powerful Analytical Tool for Research and Biomedical Applications

: The functioning of bioluminescent systems in most of the known marine organisms is based on the oxidation reaction of the same substrate-coelenterazine (CTZ), catalyzed by luciferase. Despite the diversity in structures and the functioning mechanisms, these enzymes can be united into a common group called CTZ-dependent luciferases. Among these, there are two sharply different types of the system organization-Ca2+-regulated photoproteins and luciferases themselves that function in accordance with the classical enzyme-substrate kinetics. Along with deep and comprehensive fundamental research on these systems, approaches and methods of their practical use as highly sensitive reporters in analytics have been developed. The research aiming at the creation of artificial luciferases and synthetic CTZ analogues with new unique properties has led to the development of new experimental analytical methods based on them. The commercial availability of many ready-to-use assay systems based on CTZ-dependent luciferases is also important when choosing them by first-time-users. The development of analytical methods based on these bioluminescent systems is currently booming. The bioluminescent systems under consideration were successfully applied in various biological research areas, which confirms them to be a powerful analytical tool. In this review, we consider the main directions, results, and achievements in research involving these luciferases.

Use of dry carbonic acid gas baths to correct human biological age

Relevance. The physiotherapy method of dry carbonic acid gas baths (DCAGB) mediated through the effects of carbon dioxide (CO2) is a minimally invasive treatment and prevention method of many human diseases. However, the CO2 effect on the rate of human aging has not been sufficiently studied. Therefore, it is relevant to study the effect of dry carbonic acid gas baths (DCAGB) physiotherapy method on peripheral blood indicators and biological age. Purpose. To assess the effect of carbon dioxide in dry carbonic acid gas baths condition on peripheral blood indicators and biological age in patients of different age groups. Patients and methods. An interventional single center controlled clinical trial was conducted on 140 male patients. Within 1 day before the DCAGB sessions course start (10 sessions 40 minutes each) and 1 day after course completion, patients’ peripheral blood samples were studied, as well as biological and cardiopulmonal age on the patented method was determined.

Results. DCAGB course reduced biological age in young and middle-aged patients by 5.5 years (p<0.001), elderly and old patients – by 4.7 years (p<0.001), elderly and old patients had a decrease in cardiopulmonal bio age by 8.6 years (p<0.01).

Conclusion. The course of DCAGB sessions slowed the aging rate of the human body from young to old age, which was probably associated with antihypoxic, antitoxic, antioxidant effects of carbon dioxide, as well as possibly with erythropoiesis activation.