Chronic cardiac rejection is represented by cardiac allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) known to cause severe complications. These processes are accompanied by ...remarkable changes in the cardiac extra cellular matrix (cECM). The aim of our study was to analyse the cECM remodelling in chronic rejection and to elucidate a potential role of ED-A domain containing fibronectin (ED-A⁺ Fn), alpha smooth muscle actin (ASMA) and B domain containing tenascin-C (B⁺ Tn-C). A model of chronic rejection after heterotopic rat heart transplantation was used. Allografts, recipient and control hearts were subjected to histological assessment of rejection grade, to real-time PCR based analysis of 84 genes of ECM and adhesion molecules and to immunofluorescence labelling procedures, including ED-A⁺ Fn, ASMA and B⁺ Tn-C antibodies. Histological analysis revealed different grades of chronic rejection. By gene expression analysis, a relevant up-regulation of the majority of ECM genes in association with chronic rejection could be shown. For 8 genes, there was a relevant up-regulation in allografts as well as in the corresponding recipient hearts. Association of ASMA positive cells with the grade of chronic rejection could be proven. In CAV and also in CIF there were extensive co-depositions of ED-A⁺ Fn, ASMA and B⁺ Tn-C. In conclusion, chronic cardiac allograft rejection is associated with a cECM remodelling. ASMA protein deposition in CAV, and CIF is a valuable marker to detect chronic rejection. Interactions of VSMCs and Fibro-/Myofibroblasts with ED-A⁺ Fn and B⁺ Tn-C might functionally contribute to the development of chronic cardiac rejection.
Abstract
Background
Adipose-derived stem cells (ADSC) are multipotent cells implicated in tissue homeostasis. Obesity represents a chronic inflammatory disease associated with metabolic dysfunction ...and age-related mechanisms, with progressive accumulation of senescent cells and compromised ADSC function. In this study, we aimed to explore mechanisms associated with the inflammatory environment present in obesity in modulating ADSC to a senescent phenotype. We evaluated phenotypic and functional alterations through 18 days of treatment. ADSC were cultivated with a conditioned medium supplemented with a pool of plasma from eutrophic individuals (PE, n = 15) or with obesity (PO, n = 14), and compared to the control.
Results
Our results showed that PO-treated ADSC exhibited decreased proliferative capacity with G2/M cycle arrest and
CDKN1A
(p21
WAF1/Cip1
) up-regulation. We also observed increased senescence-associated β-galactosidase (SA-β-gal) activity, which was positively correlated with TRF1 protein expression. After 18 days, ADSC treated with PO showed augmented
CDKN2A
(p16
INK4A
) expression, which was accompanied by a cumulative nuclear enlargement. After 10 days, ADSC treated with PO showed an increase in NF-κB phosphorylation, while PE and PO showed an increase in p38MAPK activation. PE and PO treatment also induced an increase in senescence-associated secretory phenotype (SASP) cytokines IL-6 and IL-8. PO-treated cells exhibited decreased metabolic activity, reduced oxygen consumption related to basal respiration, increased mitochondrial depolarization and biomass, and mitochondrial network remodeling, with no superoxide overproduction. Finally, we observed an accumulation of lipid droplets in PO-treated ADSC, implying an adaptive cellular mechanism induced by the obesogenic stimuli.
Conclusions
Taken together, our data suggest that the inflammatory environment observed in obesity induces a senescent phenotype associated with p38MAPK/NF-κB axis, which stimulates and amplifies the SASP and is associated with impaired mitochondrial homeostasis.
Bipolar disorder (BD) has been associated with increased rates of age-related diseases, such as type II diabetes, metabolic syndrome, osteoporosis, and cardiovascular disorders. Several biological ...findings have been associated with age-related disorders, including increased oxidative stress, inflammation, and telomere shortening. The objective of this study was to compare telomere length among participants with BD at early and late stages and age- and gender-matched healthy controls.
Twenty-six euthymic subjects with BD and 34 healthy controls were recruited. Genomic DNA was extracted from peripheral blood and mean telomere length was measured using real-time quantitative polymerase chain reaction.
Telomere length was significantly shorter in both the early and late subgroups of BD subjects when compared to the respective controls (p = 0.002 and p = 0.005, respectively). The sample size prevented additional subgroup analyses, including potential effects of medication, smoking status, and lifestyle.
This study is concordant with previous evidence of telomere shortening in BD, in both early and late stages of the disorder, and supports the notion of accelerated aging in BD.
There is growing interest in PEGylation of cationic polymeric vehicles for gene delivery in order to improve vehicle stability and reduce toxicity, but little is known about the effects of PEG ...coatings on transfection. We used a polymer from the poly(amine-co-ester) (PACE) family blended with PEG-conjugated PACE at different ratios in order to explore the effects of polyplex PEGylation on the transfection efficiency of plasmid DNA, mRNA, and siRNA in vitro and mRNA in vivo. We discovered that concentrations of PACE-PEG as low as 0.25% by weight improved polyplex stability but also inhibited transfection in vitro. In vivo, the effect of PACE-PEG incorporation on mRNA transfection varied by delivery route; the addition of PACE-PEG improved local delivery to the lung, but PEGylation had little effect on intravenous systemic delivery. By both delivery routes, transfection was inhibited at concentrations higher than 5 wt% PACE-PEG. These results demonstrate that excess PEGylation can be detrimental to vehicle function, and suggest that PEGylation of cationic vehicles must be optimized by PEG content, cargo type, and delivery route.
•Low PEG incorporation can significantly improve stability of PACE polyplexes.•Optimal PEG incorporation in vitro is not reflective of optimal in vivo efficacy.•The effect of PEG on mRNA delivery in vivo depends on the delivery route.•PEGylation at low levels improves localized mRNA delivery to the lung.
Branching is a key structural parameter of polymers, which can have profound impacts on physicochemical properties. It has been demonstrated that branching is a modulating factor for mRNA delivery ...and transfection using delivery vehicles built from cationic polymers, but the influence of polymer branching on mRNA delivery remains relatively underexplored compared to other polymer features such as monomer composition, hydrophobicity, pKa, or the type of terminal group. In this study, we examined the impact of branching on the physicochemical properties of poly(amine-co-esters) (PACE) and their efficiency in mRNA transfection in vivo and in vitro under various conditions. PACE polymers were synthesized with various degrees of branching ranging from 0 to 0.66, and their transfection efficiency was systemically evaluated. We observed that branching improves the stability of polyplexes but reduces the pH buffering capacity. Therefore, the degree of branching (DB) must be optimized in a delivery route specific manner due to differences in challenges faced by polyplexes in different physiological compartments. Through a systematic analysis of physicochemical properties and mRNA transfection in vivo and in vitro, this study highlights the influence of polymer branching on nucleic acid delivery.
An inhalable platform for messenger RNA (mRNA) therapeutics would enable minimally invasive and lung-targeted delivery for a host of pulmonary diseases. Development of lung-targeted mRNA therapeutics ...has been limited by poor transfection efficiency and risk of vehicle-induced pathology. Here, we report an inhalable polymer-based vehicle for delivery of therapeutic mRNAs to the lung. We optimized biodegradable poly(amine-
-ester) (PACE) polyplexes for mRNA delivery using end-group modifications and polyethylene glycol. These polyplexes achieved high transfection of mRNA throughout the lung, particularly in epithelial and antigen-presenting cells. We applied this technology to develop a mucosal vaccine for severe acute respiratory syndrome coronavirus 2 and found that intranasal vaccination with spike protein-encoding mRNA polyplexes induced potent cellular and humoral adaptive immunity and protected susceptible mice from lethal viral challenge. Together, these results demonstrate the translational potential of PACE polyplexes for therapeutic delivery of mRNA to the lungs.
There is evidence that maternal milieu and changes in environmental factors during the prenatal period may exert a lasting impact on the brain health of the newborn, even in case of neonatal brain ...hypoxia-ischemia (HI). The present study aimed to investigate the effects of maternal environmental enrichment (EE) on HI-induced energetic and metabolic failure, along with subsequent neural cell responses in the early postnatal period. Male Wistar pups born to dams exposed to maternal EE or standard conditions (SC) were randomly divided into Sham-SC, HI-SC, Sham-EE, and HI-EE groups. Neonatal HI was induced on postnatal day (PND) 3. The Na+,K+-ATPase activity, mitochondrial function and neuroinflammatory related-proteins were assessed at 24 h and 48 h after HI. MicroPET-FDG scans were used to measure glucose uptake at three time points: 24 h post-HI, PND18, and PND24. Moreover, neuronal preservation and glial cell responses were evaluated at PND18. After HI, animals exposed to maternal EE showed an increase in Na+,K+-ATPase activity, preservation of mitochondrial potential/mass ratio, and a reduction in mitochondrial swelling. Glucose uptake was preserved in HI-EE animals from PND18 onwards. Maternal EE attenuated HI-induced cell degeneration, white matter injury, and reduced astrocyte immunofluorescence. Moreover, the HI-EE group exhibited elevated levels of IL-10 and a reduction in Iba-1 positive cells. Data suggested that the regulation of AKT/ERK1/2 signaling pathways could be involved in the effects of maternal EE. This study evidenced that antenatal environmental stimuli could promote bioenergetic and neural resilience in the offspring against early HI damage, supporting the translational value of pregnancy-focused environmental treatments.
•Maternal EE prevented HI-induced mitochondrial, Na+,K+-ATPase, and metabolic impairments, preserving cell energy function.•Maternal EE regulates AKT/ERK1/2 signaling pathways, offering a potential mechanism for its protective effects.•Maternal EE restored glucose uptake, interhemispheric connectivity, and maintained neuronal and oligodendrocyte populations.•Maternal EE induced an anti-inflammatory response as supported by increased IL-10 levels and reduced Iba-1 positive cells.•The hippocampus and parietal cortex bear notably distinct responses to neonatal EE and maternal EE experiences.
Severe therapy-resistant asthma (STRA) is closely associated with distinct clinical and inflammatory pheno-endotypes, which may contribute to the development of age-related comorbidities. Evidence ...has demonstrated a contribution of accelerated telomere shortening on the poor prognosis of respiratory diseases in adults. Eotaxin-1 (CCL11) is an important chemokine for eosinophilic recruitment and the progression of asthma. In the last years has also been proposed as an age-promoting factor. This study aimed to investigate the association of relative telomere length (rTL) and eotaxin-1 in asthmatic children. Children aged 8-14 years (n=267) were classified as healthy control (HC, n=126), mild asthma (MA, n=124) or severe therapy-resistant asthma (STRA, n=17). rTL was performed by qPCR from peripheral blood. Eotaxin-1 was quantified by ELISA from fresh-frozen plasma. STRA had shorter telomeres compared to HC (
=0.02) and MA (
=0.006). Eotaxin-1 levels were up-regulated in STRA median; IQR25-75) (1,190 pg/mL; 108-2,510) compared to MA (638 pg/mL; 134-1,460) (
=0.03) or HC (627 pg/mL; 108-1,750) (
<0.01). Additionally, shorter telomeres were inversely correlated with eotaxin-1 levels in STRA (r=-0.6,
=0.013). Our results suggest that short telomeres and up-regulated eotaxin-1, features of accelerated aging, could prematurely contribute to a senescent phenotype increasing the risk for early development of age-related diseases in asthma.
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