Rysevaitė-Kyguolienė, Kristina

Angiotenzinas II (Ang II), pagrindinis renino-angiotenzino sistemos komponentas, pasižymi plačiu poveikiu uždegiminiuose procesuose, oksidacinio streso sukėlime bei kraujagyslių pažeidimo patogenezėje. Naujausi tyrimai rodo, kad šie mechanizmai gali pasireikšti ne tik širdies ir kraujagyslių, bet ir virškinamojo trakto ligų, tokių kaip divertikuliozė, patogenezėje. Tikslas. Nustatyti angiotenzino II sąsajas su kraujagyslių pažeidimu divertikuliozės patogenezėje. Metodai. Mokslinės literatūros paieška atlikta 2025 m. vasario 1 d. − birželio 1d. PubMed, ScienceDirect duomenų bazėse. Į analizę įtraukti naujausi, ne senesni nei 10 metų, anglų kalba publikuoti tyrimai, nagrinėjantys Ang II sąsajas su kraujagyslių pažeidimu. Įtraukta 13 publikacijų, atitinkančių įtraukties kriterijus. Rezultatai. Analizuojant literatūrą, nustatyta, kad Ang II, veikdamas AT1 receptorius, aktyvina oksidacinį stresą kraujagyslių endotelyje, skatindamas NADPH oksidazės izoformų (ypač NOX2 ir NOX4) aktyvaciją ir didindamas reaktyviųjų deguonies formų (ROS) gamybą. Tai lemia azoto oksido (NO) sumažėjimą, kraujagyslių vazodilatacijos sutrikimą ir endotelio disfunkciją. Be to, Ang II sukelia kraujagyslių sienelės uždegimą ir remodeliaciją, aktyvindamas prouždegiminius signalinius kelius, tokius kaip NF-κB, ir didindamas adhezijos molekulių ICAM-1 bei VCAM-1 raišką. Šie procesai skatina imuninių ląstelių infiltraciją ir mikrocirkuliacijos sutrikimus žarnyno sienelėje, kurie kartu su oksidacine žala ir audinių remodeliacija sudaro palankias sąlygas divertikulų formavimuisi. Taip pat pastebėtas Ang II poveikis mitochondrijų funkcijai ir ląstelių apoptozei, silpninantis žarnyno sienelės struktūrą. Šie mechanizmai glaudžiai siejasi su kraujagyslių pažeidimu ir žarnyno mikrocirkuliacijos disfunkcija divertikuliozės patogenezėje. Išvados. Angiotenzinas II per AT1 receptorius yra esminis molekulinis mediatorius, skatinantis oksidacinį stresą, uždegimą ir kraujagyslių mikrocirkuliacijos pažeidimus divertikuliozės patogenezėje. Šie procesai lemia žarnyno sienelės struktūros pokyčius ir mikrocirkuliacijos sutrikimus, kurie gali prisidėti prie divertikulų susidarymo ir ligos progresavimo.

Background. Heart areas enriched in endings of sensory nerve fibres (NEs) play a role as reflexogenic zones (RZs), where primary afferent signals initiate neural mechanisms controlling heart activity. Distribution, appearance, and chemical phenotypes of cardiac NEs remain under consideration. Study aims to characterise the morphological diversity of NEs in mammalian and human hearts, exposing links between their structural patterns and chemical phenotypes.

Introduction The jugular/nodose ganglia (J/NG) complex contains sensory neurons expressing neuropeptides such as CGRP, nNOS, and TTN3, which are essential for vagal signaling. Aging and arterial hypertension may induce structural remodeling of these ganglia and alter the morphology of peptide-expressing neurons. However, the relationship between ganglion morphology, neuronal size, and peptide-specific expression across age and hypertensive states remains poorly defined. Aim of the study To evaluate age- and hypertension-related morphological changes in the J/NG complex, focusing on ganglion size, neuronal soma size, neuron density, and peptide-specific neuronal morphology in Wistar–Kyoto (WKY) and spontaneously hypertensive (SHR) rats. Materials and methods Cryosections of the J/NG complex were immunohistochemically stained for CGRP, nNOS, TTN3, and PGP9.5. Fluorescent secondary antibodies (Cy3, FITC, A488) were used for visualization by fluorescence microscopy. Ganglion area, neuronal soma area, neuron density, and peptide-specific neuronal morphology were quantified using ImageJ and AxioImage software. Results Ganglion size positively correlated with neuron number in young and middle-aged animals, whereas this relationship was absent in aged rats. SHR exhibited increased neuron density during early stages of hypertension, while WKY rats demonstrated age-dependent increases in neuron density. Neuronal soma size increased with age in SHR but remained relatively stable in WKY rats; however, neurons in SHR were consistently smaller than those in WKY rats in young and middle-aged groups. Peptide- and side-specific differences in neuronal morphology were prominent in younger animals but progressively diminished with aging. Conclusions Aging and hypertension are associated with distinct, peptide-specific morphological remodeling of the jugular/nodose ganglia. Hypertension primarily affects neuronal size and density at earlier stages, while aging reduces structural and peptide-specific differences, leading to convergence of neuronal morphology in older animals.

Background: Intestinal dysmotility in type 2 diabetes mellitus (T2DM) may involve impaired cholinergic and incretin-mediated regulation. This study compared cholinergic-induced jejunal contractility and evaluated the effects of Glucagon like peptide-1 (GLP-1) and Gastric inhibitory polypeptide (GIP) in relation to the expression of these peptides, their receptors, and Dipeptidyl peptidase 4 (DPP-4) in jejunal muscle of obese patients with and without T2DM.

Methods: Jejunal samples were collected from 32 obese patients undergoing bariatric surgery (14 with and 18 without T2DM). Jejunal muscular tissue was examined for expression of GLP-1, GIP, and for expression and localization of DPP-4 and incretin receptors (GLP-1R and GIPR). In addition, DPP-4 enzymatic activity was quantitatively assessed. Contractility of circular and longitudinal muscle strips was assessed in vitro following bethanechol stimulation, with or without GLP-1 or GIP.

Results: GLP-1 receptors were detected in smooth muscle nuclei and enteric ganglia, while GIP receptors localized to both muscle layers. DPP-4 was present in neural and muscular compartments. In T2DM, GIPR and DPP-4 expression and activity were increased, while GIP protein was reduced. GLP-1 protein levels tended to be higher. Longitudinal muscle contractility independent of neural input was reduced in T2DM. GLP-1 selectively inhibited circular muscle contractions in both groups, whereas GIP had no effect.

Conclusion: This study demonstrates that reduced cholinergic activity in longitudinal muscle, lower GIP, and increased GLP-1 in T2DM indicate a shifted local incretin environment that may collectively suppress jejunal contractility.

The jugular–nodose ganglion (JNG) complex of the vagus nerve is a key autonomic relay. However, how aging and hypertension affect its neuropeptide expression remains unclear. This study examined age-, strain-, and side-dependent expression of CGRP, nNOS, and TTN3 in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats. Methods Male SHR and WKY rats were grouped as young (4–9 weeks), middle-aged (39–42 weeks), or old (60–63 weeks). JNG tissues were processed for immunohistochemistry with antibodies against CGRP, nNOS, and TTN3. Neuronal expression was quantified bilaterally and compared using unpaired and paired t-tests. Results In young rats, CGRP-positive neurons accounted for 11.05% in SHR and 0.98% in WKY (p = 0.0007); in middle-aged rats – 6.79% vs. 0.32% (p < 0.0001); no significant difference in old rats (28.36% vs. 34.45%, p = 0.11). nNOS expression was lower in young SHR (3.35%) than WKY (37.07%, p = 0.01) but similar in middle-aged (31.64% vs. 29.78%) and old rats (40.27% vs. 38.53%). TTN3-positive neurons were more frequent in SHR across all ages: young (70.13% vs. 47.23%, p < 0.0001), middle-aged (42.56% vs. 78.30%, p = 0.0025), and old (70.11% vs. 44.22%, p = 0.0086). Neuron size in SHR increased with age (Me = 23.23→24.97 µm²), whereas WKY showed no significant change. Neuron density was higher in young SHR (762/mm²) vs. WKY (608/mm²) and declined with age. Ganglion area correlated positively with neuron number in young and middleaged but not old animals. Discussion Hypertension induces dynamic, age-dependent neurochemical and morphological remodeling of the JNG. Elevated CGRP, reduced nNOS, and persistent TTN3 upregulation suggest adaptive–maladaptive interplay in baroreceptor pathways. Although these results were obtained in rats, the JNG shares key molecular features with the human vagus nerve. Direct evidence of age- or hypertension-related morphological changes in human vagal ganglia is still lacking, but many mammalian species exhibit comparable autonomic aging, supporting the translational relevance of these findings.

Background: Cyano-phycocyanin (C-PC), derived from cyanobacterial biomass, exhibits antioxidant, antiinflammatory, and even anticancer properties [1]. However, its high molecular weight and environmental sensitivity present significant challenges for topical application [2]. Objective: Determination the physicochemical properties, storage stability, and topical skin delivery of C-PC loaded glycerotransfersomes. Methods: Glycerotransfersomes were produced via sonication using an ultrasonic disintegrator Soniprep 150, with formulation details outlined in Table 1. Vesicle size (mean diameter, MD), polydispersity index (PI), and zeta potential (ZP) were assessed using Dynamic Light Scattering with a Zetasizer Ultra. Encapsulation efficiency (EE) was determined using dialysis, followed by spectrophotometric quantification of C-PC content. Ex vivo skin permeation studies were conducted using human skin. Stability was evaluated by tracking changes in MD, PI, and ZP over 8-month storage period at 4°C. Statistical analysis was performed using IBM SPSS Statistics version 29.0. Results: Glycerotransfersomes containing cholesterol had slightly smaller mean diameters (92.80 nm) compared to those without cholesterol (101.92 nm). PI values were approximately 0.17, and ZP values below -30 mV. EE was approximately 51 %. Formulations remained stable over 8 months at 4 °C. Ex vivo studies revealed significant enhanced C-PC accumulation in the stratum corneum with Glycerotransferosomes compared to a C-PC solution, independent of penetration enhancer use such as propylene glycol. Notably, glycerotransferosomes without cholesterol demonstrated superior C-PC accumulation in the stratum corneum compared to those containing cholesterol. Conclusion: Glycerotransferosomes significantly improve the accumulation of C-PC in the stratum corneum compared to a standard C-PC solution. The absence of cholesterol further enhances this accumulation, suggesting that cholesterol-free glycerotransferosomes may be the optimal formulation. Both formulations exhibit suitable physicochemical properties and stability for extended storage.

This study aimed to develop and evaluate cyano-phycocyanin (C-PC)-loaded enriched transfersomes for topical application, improved skin delivery, and antioxidant protection. The main objective was to overcome the limitations associated with C-PC's instability and poor skin permeability due to its high molecular weight and hydrophilicity. Six formulations were prepared using an organic solvent-free two-step method: glycerol-enriched transfersomes (Gly-transfersomes),glycerol and cholesterol-enriched transfersomes (Gly-chol-transfersomes),hyaluronate-enriched transfersomes (Hyal-transfersomes),hyaluronate and cholesterol-enriched transfersomes (Hyal-chol-transfersomes),glycerol and hyaluronate-enriched transfersomes (Hyal-gly-transfersomes), anda combination of all three (Hyal-gly-chol-transfersomes). Empty vesicles were prepared via direct sonication, then C-PC was gently loaded using mild sonication in a temperature-controlled ultrasonic bath. All formulations demonstrated properties suitable for skin delivery, with mean diameters <115 nm, polydispersity indexes <0.2, and zeta potential below -30 mV. Cryo- transmission electron microscopy confirmed spherical, unilamellar or oligolamellar morphology. Gly- and Gly-chol-transfersomes exhibited the highest encapsulation efficiency (∼52 %) and remained stable for up to 8 months at 4 °C. Antioxidant activity of C-PC (∼23-27 μmol TE/g of dry C-PC) was confirmed via DPPH assay. Biological tests on HaCaT cells exposed to H2O2-induced oxidative stress showed ∼80 % cell viability after treatment with C-PC formulations, compared to ∼60 % in untreated cells, indicating cytoprotective activity. Ex vivo skin penetration studies revealed significantly higher C-PC accumulation in the epidermis especially for Gly- and Gly-chol-transfersomes versus aqueous C-PC. These findings confirm the potential of enriched transfersomes as effective carriers to improve the skin delivery and bioactivity of C-PC in antioxidant skin care formulations.

Background: This study aims to analyse the innervation of the small intensely fluorescent (SIF) cells within the rat heart, seeking to examine the supposable neuroanatomical basis for the paradoxical increase of the sympathetic activity of the heart following electrical stimulation of the vagal nerves. Methods: Neuronal markers and confocal laser scanning microscopy were used to analyse cardiac SIF cells and their innervation in 12 rats. Results: The findings of the present study demonstrate the limited number of nerve fibres (NFs) adjacent to SIF cells. These NFs were of nitrergic phenotype and negative to adrenergic and cholinergic neuronal markers. We revealed two morphologic patterns of these NFs networking SIF cells. The first type of nitrergic NFs surrounded the SIF cells tightly, and their axons contained numerous varicosities. The second pattern had nitrergic axons with fewer or no varicosities on their terminals. Since most SIF cells identified in the rat hearts (∼80%) had no nerve fibres targeting them, the innervated SIF cells may be considered as particular catecholaminergic cells mediating between the heart neural regulation and the endocrine mechanism of SIF cells. Conclusion: Since our earlier data demonstrate the absolute prevalence of nitric oxide synthesising neurons in the rat vagal sensory ganglia, we conclude that nitrergic nerve axons basketed SIF cells are the vagal sensory axons presumably controlling the cardiac SIF cells in rats. Ethics: On behalf of all authors, herewith I declare that the study described in the submitted manuscript was performed according to all ethic requirements under permission No. LT-61-19-004 issued by the State Service for Food and Veterinary.

Hypertension impacts the autonomic nervous system, particularly through changes in sensory ganglia associated with the vagus nerve. The nodose ganglia (NG), a key hub in cardiovascular regulation, contain neuropeptides such as CGRP, nNOS, and TTN3, essential for neural signaling. This study investigates changes in neuropeptides CGRP, nNOS, and TTN3, and neuronal size within NG of spontaneously hypertensive rats (SHR) compared to normotensive Wistar-Kyoto rats (WKY) across ages (9–64 weeks). Left and right ganglia differences were also examined. Cryosections of NG were immunohistochemically stained with primary antibodies against CGRP, nNOS, TTN3, and PGP9.5 (general neuronal marker). Fluorochromes Cy3, FITC, and A488-conjugated secondary antibodies were used for visualization under fluorescence microscopy. Neuropeptide expression was quantified with ImageJ, and neuronal area calculated with AxioImage. Statistical analyses included T-tests and one-way ANOVA. With SHR rats exhibiting chronic hypertension and WKY rats serving as controls, significant differences in neuropeptide expression were observed between the groups. Young SHR showed higher CGRP and TTN3 expression (p<0.01), while older SHR displayed primarily TTN3 differences. Middle-aged SHR presented elevated CGRP and TTN3 expression, and very old SHR demonstrated increased nNOS and TTN3, especially in the left NG. Additionally, older SHR showed significant left-sided CGRP, nNOS, and TTN3 expression differences, with age-related neuronal size differences, notably for nNOS in NG (p<0.05). This study reveals age-related neuropeptide expression differences in NG between hypertensive and normotensive rats, with SHR showing higher CGRP, nNOS, and TTN3 levels, especially in the left-sided NG. These findings underscore the role of NG neuropeptide alterations in neurogenic hypertension pathology and highlight aging’s impact on these mechanisms.

Objectives. The study aims to demonstrate the morphologic pattern of innervation in the aorta since these specific data have pivotal importance for understanding the mechanism of painless aneurysm development. Materials and methods. The ascending, descending (thoracic and abdominal) aorta and aortic arch of ten rats were examined microscopically following the staining of their neural structures for general (acetylcholinesterase, AChE), sympathetic (tyrosine hydroxylase, TH), and sensory (calcitonin gene-related peptide, CGRP) axonal markers. Results. The evident AChE(+) nerves linked the sympathetic trunk with the aorta wall. These tiny nerves derived from sympathetic ganglia accompany the intervertebral arteries up to their access to the aortic wall. In the ascending aorta, the TH(+) axons were most numerous in the adventitial layer and occupied 1.5% of the area, while the CGR(+) – 0,2% only. In the aortic arch, adrenergic axons comprised 1,4% and CGRP(+) – 0,1%, respectively. In the descendent aorta, TH(+) axons covered 0,4% (thoracic part) and 1,1% (abdominal part) of the wall area, whereas CGRP(+) – 0,14% and 0,12%, respectively. The aortic wall in rats is supplied by 3–4 tiny nerves derived bilaterally from sympathetic trunk ganglia at the descending thoracic aorta. The average length of these nerves is 7 mm, and they exhibit sympathetic adrenergic and sympathetic afferent axons that extend to the aortic wall. Conclusions. The results of this study demonstrate the sympathetic and sensory innervation within the aortic walls in rats and further studies are needed for confirmation of our findings in large experimental animals and humans. The revealed significant quantitative differences in axonal density and morphologic pattern of innervation in the specific part of the aorta suggest the hypothesis about possible different neural regulation and sensibility of the aneurysm development in distinct parts of the aorta.