Traumatic brain injury (TBI) is one of the most common forms of neurotrauma, accompanied by significant disruptions in neuronal homeostasis and intercellular communication. A key protein involved in these processes is connexin 43 (Cx43), which facilitates the formation of gap junctions in the astrocytic network. In this study, using confocal and immunofluorescence microscopy, ultrastructural analysis, and molecular modeling, we investigated the dynamics of Cx43 expression and structural changes in neuroglia during various post-traumatic periods following TBI. It was shown that in the acute phase, 24 h post-injury, there is a reduction in Cx43 expression, accompanied by apoptotic neuronal degradation, disruption of nuclear NeuN localization, and destruction of cellular ultrastructure. By 7 days post-injury, a significant increase in Cx43 levels was observed, along with the formation of protein aggregates associated with pronounced reactive astrogliosis. Peripheral blood analysis revealed persistent neutrophilia, lymphopenia, and reduced monocyte levels, reflecting a systemic inflammatory response and immunosuppression, which was corroborated by a custom-trained neural network-based computer vision model. Linear regression and correlation analyses further identified a strong positive association between normalized monocyte levels and Cx43 expression, a moderate negative correlation with lymphocytes, and no significant correlation with neutrophils. Using a custom-built computer vision model, we confirmed these hematological trends and detected subtle changes, such as early increases in platelet counts, that were not captured by manual evaluation. The model demonstrated strong performance in classifying common blood cell types and proved to be a valuable tool for monitoring dynamic post-traumatic shifts in blood. Molecular dynamics modeling of Cx43 identified a pH-dependent mechanism of conformational reorganization under post-traumatic acidosis, mediated by the interaction between protonated His142 and Glu103. This mechanism mimics the structural consequences of the pathogenic E103K mutation and may play a critical role in the neurotoxic effects of Cx43 in TBI. These findings highlight the complexity of Cx43 regulation under traumatic conditions and its potential significance as a target for neuroprotective therapy.

Hydrogen sulfide (H₂S) is a gasotransmitter that plays a crucial role in regulating pathological processes following injury to the central and peripheral nervous systems. This review systematizes current data on various classes of H₂S donors and inhibitors of its biosynthesis in neurotrauma and related experimental models. Inorganic donors (e.g., NaHS, Na₂S, and STS) rapidly suppress oxidative stress and inflammation, supporting the recovery of synaptic plasticity and cognitive function. Organic donors (e.g., GYY4137, ACS67, ACS84, SPRC, ADT-OH and its derivatives, S-memantine, and MTC) provide sustained H₂S release, stabilize the blood–brain barrier, and exhibit antiapoptotic activity. Natural donors (e.g., DADS, DATS, and SAMe) demonstrate high biocompatibility, inhibit pyroptosis, and enhance antioxidant defense mechanisms. Hybrid systems—including nanoparticles and hydrogels—enable targeted delivery and prolonged action, thereby stimulating regeneration and angiogenesis. Thiol-activated donors (e.g., COS/H₂S and AlaCOS) allow controlled H₂S release, offering broad opportunities for precise modulation of its concentration within target tissues. Inhibitors (e.g., AOAA, PAG, oxamic hydrazide 1, L-aspartic acid, benserazide, and NSC4056) of H₂S biosynthesis underscore the physiological importance of this gasotransmitter, as their administration enhances neuroinflammation and diminishes neuroprotection. The analysis reveals a general pattern: all classes of H₂S donors effectively modulate key pathological mechanisms, differing in their rate, duration, and specificity of action. These findings highlight the therapeutic promise of H₂S-based pharmacological agents in clinical neurotraumatology, while emphasizing the need for further research to optimize delivery systems, enhance efficacy, and minimize adverse effects.

Copper(II) complexes with synthetic oligonucleotides consisting of repeating adenine–thymine and guanine–cytosine complementary base pairs have been studied by UV spectroscopy and simulated by DFT quantum chemical calculations at the B3LYP/6-311G++(d,p) level of theory with inclusion of solvation (hydration) effects. The obtained data suggest selective interaction of copper(II) ions with guanine–cytosine complementary pairs, followed by DNA cross-linking at those sites.