Search Results (63)

Diabetic nephropathy (DN) is the most common cause of kidney failure worldwide. Mesenchymal stromal cells (MSCs) have demonstrated promise for treating DN by promoting kidney repair and regulating inflammation. Allogeneic (Allo)-MSCs may have similar or superior anti-inflammatory effects to autologous (Auto)-MSCs but also have potential to elicit adverse immune responses due to major histocompatibility complex (MHC) mismatches. To better understand how MSC-delivered allo-antigens influence therapeutic effects of Allo-MSCs compared to Auto-MSCs in DN, lentiviral transduction was used to generate adipose-derived MSCs (ADSCs) from DBA/2J (H-2^d) mice which expressed an allogeneic class I MHC protein (H-2K^b). H-2K^b-ADSCs were injected intravenously into male DBA/2J mice at 11 and 13 weeks after initiation of diabetes, and their effects on renal functional and structural indices were compared at week 15 with those of diabetic DBA/2J recipients of vehicle alone or of empty vector-transduced DBA/2J ADSCs (EV-ADSCs). Both EV-ADSCs and H-2K^b-ADSCs resulted in reduced kidney/total body weight ratio, blood urea nitrogen (BUN), urine albumin creatinine ratio (uACR), mesangial matrix expansion (MME) and renal fibrosis compared to vehicle alone, without influencing glycemia or survival. However, H-2K^b-ADSCs recipients had greater reductions in BUN and uACR, reduced intra-renal myeloid cell infiltration, increased splenic regulatory T cell (Treg) proportions and increased intra-renal Treg infiltration and FOXP3 and IL-10 mRNA. Nonetheless, recipients of H-2K^b-ADSCs also had decreased splenic CD4/CD8 T cell ratios, increased circulating anti-H-2K^b IgG antibodies and histological and biochemical evidence of inflammatory liver injury. These novel findings demonstrated that ADSCs expressing an MHC-I allo-antigen had superior beneficial effects on DN than fully autologous ADSCs. Improved DN severity was associated with immune modulation, including Treg enhancement, but also had potentially detrimental immunological effects in mice with established diabetes. The results highlight the need for further investigation of the immune modulatory effects of Allo-MSCs in diabetes and its organ-specific complications. Full article

Maternal immune tolerance and controlled inflammatory responses are essential for fetal development and successful pregnancy. Regulatory T cells (Tregs) and B cells with regulatory properties (Bregs) maintain this balance by limiting excessive immune activation through the secretion of anti-inflammatory and tolerogenic cytokines, such as IL-10, TGF-β, and IL-35. Moreover, alterations in the costimulatory potential of antigen-presenting cells (APCs), including B cells, modulate the activation and differentiation of T cells. Toll-like receptors (TLRs), particularly TLR9, influence B-cell antigen presentation and cytokine production, thereby affecting the balance between pro-inflammatory and tolerogenic responses at the maternal–fetal interface. TLR9 overexpression has been observed in several pregnancy-related disorders in both humans and murine models. In this study, we examine whether blocking TLR9 shortly after mating could improve pregnancy outcomes and modulate the regulatory and antigen-presenting functions of B cells, as well as their interactions with T cells. Using an abortion-prone murine model (CBA/J × DBA/2J), we show that intraperitoneal administration of a TLR9 antagonist (ODN 2088) shortly after mating increases embryo resorption in CBA/J females compared to controls without affecting implantation. Flow cytometry analysis further reveals that mice receiving the TLR9 antagonist are characterized by downregulation of CD80 and upregulation of CD86 on B cells, accompanied by reduced expression of CD40L and CD28 on T cells, as well as a lower percentage of Tregs and activated T cells. In conclusion, blocking TLR9 signaling shortly after mating does not improve pregnancy outcomes; conversely, it exacerbates pregnancy loss in the CBA/J × DBA/2J abortion-prone model, while altering the costimulatory phenotype of B and T cells and impairing Treg development during pregnancy. Full article

Because antigenic drift primarily generates amino-acid changes in the membrane-distal hemagglutinin (HA) head, broadly neutralizing antibodies (bNAbs) are being developed to target conserved epitopes in the membrane-proximal stem. Mutations to HA2 residue A44, a buried residue beneath the central stem epitope, in 2009 H1N1 viruses have been shown to cause resistance to stem-binding bNAbs. Here, we introduced A44V and A44T mutations into A/Tennessee/1-560/2009 (TN09) and A/Puerto Rico/15/2018 (PR18) and investigated their effects in cell culture, mice, and ferrets. In both virus strains, the mutations decreased HA and virus stability and decreased bNAb binding and neutralization in vitro. The mutations reduced pathogenicity and lung replication in DBA/2J mice. Ferrets were inoculated with PR18 wild-type (WT) or A44V virus, and the A44V mutation reduced day-1 and peak nasal virus titers. Airborne transmission in the A44V group occurred only after genotypic reversion (HA2-V44A) or acquisition of a distal re-stabilizing mutation (HA2-I77M). Compared to WT, an engineered PR18 virus containing both HA2 mutations (A44V and I77M) had similar growth and pathogenicity in mice in addition to decreased binding and neutralization by bNAbs. Overall, this work provides insight into the role of HA stability during HA stem-epitope remodeling that results in virus resistance to stem-binding bNAbs. Full article

Glaucoma represents a social and economic burden due to both its increasing incidence and the lack of knowledge about its physiopathology and treatment strategies. The main factor hindering progress in glaucoma research is the disease’s heterogeneity, which depends on both genetic and environmental factors. This limitation directly affects glaucoma research, posing obstacles to the elucidation of risk factors, disease mechanisms, and treatment strategies. Therefore, the need emerges to integrate pre-clinical experimental observations from different experimental models to recapitulate different aspects of the disease and achieve a successful translation to clinics. Here, we reviewed the glaucoma models that are currently available for basic and translational research, with a specific focus on models based on rodents. Regarding genetic glaucoma models, we considered the main hallmarks and limitations of DBA/2J, glutamate/aspartate transporter/excitatory amino acid carrier 1, myocilin, connective tissue growth factor, optineurin, purinergic receptor 2Y, caveolin 1, and endothelin-1 mice. Regarding other glaucoma models, we considered rodent models based on intraocular pressure elevation via perturbation of aqueous humor dynamics or on direct degeneration of retinal ganglion cells via physical or chemical damage. Full article

Consuming a high-fat diet (HFD) has been linked to gene expression alterations and negative behavior changes. The aim of this study was to evaluate the impact of a HFD on behavior and gene expression in the hippocampi of male and female mice from different strains to evaluate sex and genetic differences. C57BL/6J (B6J) and DBA/2J (D2J) mice were randomly assigned to either a control diet containing 10% kcal fat or a HFD containing 60% kcal fat for 16 weeks. Behavior was measured using the open field test for anxiety, nestlet shredding for general welfare, and novel object recognition for memory. Alpha synuclein (αSYN), amyloid precursor protein (APP), and brain-derived neurotrophic factor (BDNF) mRNA expression was assessed. The HFD led to reduced nestlet shredding for male B6J mice exclusively. There was a significant main effect of sex for fecal boli within the B6J strain and higher levels of fecal boli only for HFD male B6Js. No difference in memory was found in either strain. Significant three-way interactions between diet, sex, and strain for mRNA expression of aSYN and APP were found. However, the simple main effect of diet was only significant in the male B6J strain, revealing a 7-fold upregulation of hippocampal αSYN expression and 10-fold upregulation of APP in the HFD group compared to the control diet group. Although there was a significant strain by sex interaction effect for BDNF expression, there was no effect of diet on either strain. Overall, the HFD treatment impacted male B6J mice the greatest. This study demonstrates that biological sex and genetic factors should be considered when examining the impact of diet on behavior and the brain. Full article

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disorder whose precise etiology remains unclear, though growing evidence implicates gut microbiota in its pathogenesis. This study aimed to investigate the role of gut microbiota in the onset and progression of RA by employing fecal microbiota transplantation (FMT) in a collagen-induced arthritis (CIA) mouse model using DBA/1J and Aire⁻/⁻ strains. Mice received FMT from healthy donors, treatment-naïve RA patients, or treated RA patients in relapse, followed by assessment of microbiota composition via 16S rRNA sequencing, arthritis severity scoring, histological evaluations, and systemic inflammatory markers. The findings revealed distinct microbiota clustering patterns post-FMT across experimental groups, highlighting strain-specific colonization effects. Notably, genera such as Bifidobacterium and Paraprevotella correlated positively with arthritis severity in DBA/1J mice, whereas Corynebacterium, Enterorhabdus, and Odoribacter exhibited negative correlations, suggesting potential protective roles. Despite these microbial differences, minor variations in arthritis scores, paw inflammation, or systemic inflammation were observed among FMT groups. This indicates that although gut microbiota alterations are associated with RA pathogenesis, further investigation with larger cohorts and comprehensive sequencing approaches is essential to elucidate the therapeutic potential of microbiome modulation in autoimmune diseases. Full article

Lysophosphatidylinositols are degradation products of phosphatidylinositols within cell membranes and digestive metabolites of a high-fat diet in the gut. G-protein-coupled receptor 55 (GPR55) is a receptor that senses lysophosphatidylinositol and acts as an immune mediator, being primarily upregulated during immune cell activation. This study aimed to investigate the role of GPR55, using its antagonist, CID16020046, in a collagen-induced rheumatoid arthritis mouse model. It was observed that DBA-1J mice develop joint lesions characteristic of rheumatoid arthritis following immunization with bovine type II collagen. The administration of CID16020046 (1 mg/kg, intraperitoneally) alleviated rheumatoid arthritis symptoms and inflammatory responses. Histopathological analysis showed that CID16020046 reduced foot edema, proteoglycan loss, and bone erosion in the joints. CID16020046 also decreased rheumatoid-arthritis-induced serum IgG levels, as measured using enzyme-linked immunosorbent assays. The treatment reduced levels of pro-inflammatory cytokines (IL-1β and IL-6), Th1 cytokine (IFN-γ), and Th17 cytokine (IL-17A), along with matrix metalloproteinase-3 (MMP-3) and the receptor activator of nuclear factor-κB ligand (RANKL) in the feet. A significant reduction in splenomegaly was also observed, along with significant reductions in CD4⁺ T helper 1 (Th1) and Th17 cells in the spleen. Additionally, CID16020046 suppressed the differentiation of naïve T cells into CD4⁺IL-17⁺ Th17 cells. CID16020046 suppressed expression levels of inflammatory cytokine mRNAs in SW982 human synovial cells. In conclusion, blocking GPR55 alleviates collagen-induced rheumatoid arthritis symptoms by suppressing Th1 and Th17 cells in the spleen and pro-inflammatory cytokines in the joints, suggesting that GPR55 is a potential therapeutic target for autoimmune inflammatory diseases. Full article

Background/Objectives: Retinal ganglion cell (RGC) protection represents an unmet need in glaucoma. This study assessed the neuroprotective, antioxidant, and anti-inflammatory effect of a new nutraceutical formulation named Epicolin, based on citicoline, homotaurine, epigallocatechin-3-gallate, forskolin, and vitamins, through in vitro and in vivo studies. Methods: The neuroprotective effect of Epicolin or its single components, and Epicolin compared to an untreated control and two marketed formulations [Formulation G (FG) and N (FN)], was evaluated in neuroblastoma cells (SH-SY5Y) challenged with staurosporine. The antioxidant potential and the scavenging activity of Epicolin compared to the untreated control, and FG and FN, was evaluated in SH-SY5Y cells and through oxygen radical absorbance capacity acellular assay, respectively. Moreover, the protective effect against hypoxic damage was evaluated in Muller cells (MIO-M1) subjected to hypoxia. The efficacy of Epicolin was also evaluated in DBA/2J glaucomatous mice through the use of a pattern electroretinogram (PERG), immunostaining, and real-time PCR. Results: Among the nutraceutical formulations tested, only Epicolin showed a significant neuroprotective effect on SH-SY5Y attributable to the synergistic action of its single ingredients. As for antioxidant and scavenging activity, Epicolin showed a higher efficacy compared to FG and FN. Furthermore, Epicolin showed the same protective effect on MIO-M1 cells reducing HIF-1α expression. Finally, Epicolin treatment on DBA/2J mice protected the RGCs from loss of function, as demonstrated by PERG analysis, and attenuated their death by enhancing brain-derived neurotrophic factor (BDNF) and reducing interleukin-1 beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) expression. Conclusions: Epicolin, due to its neuroprotective, antioxidant, and anti-inflammatory properties, represents a promising potential treatment for glaucoma. Full article

The amount of sphingosine 1-phosphate (S1P) found in the synovial tissue of individuals with rheumatoid arthritis is five times greater than that in those with osteoarthritis. Our study aims to determine whether inhibiting S1P₂ can mitigate collagen-induced rheumatoid arthritis (CIA) by using an S1P₂ antagonist, JTE-013, alongside DBA-1J S1pr2 wild-type (WT) and knock-out (KO) mice. CIA causes increases in arthritis scores, foot swelling, synovial hyperplasia, pannus formation, proteoglycan depletion, cartilage damage, and bone erosion, but these effects are markedly reduced when JTE-013 is administered to S1pr2 WT mice. CIA also elevates mRNA expression levels of pro-inflammatory Th1/Th17 cytokines in the foot and spleen, which are significantly decreased by JTE-013 in S1pr2 WT mice. Additionally, CIA raises Th1/Th17 and Treg cell counts, while JTE-013 reduces these elevations in the spleens of S1pr2 WT mice. Treatment with JTE-013 or the absence of S1pr2 curtails the differentiation of naïve T cells into Th1 and Th17 cells in a dose-dependent manner. In SW982 human synovial cells, JTE-013 lowers LPS-induced increases in pro-inflammatory cytokine levels. Overall, these findings propose that blocking S1P₂ in immune and synovial cells may alleviate rheumatoid arthritis symptoms and offer a potential therapeutic approach. Full article

Recent studies have indicated that hindbrain [fourth ventricle (4V)] administration of the neurohypophyseal hormone, oxytocin (OT), reduces body weight, energy intake and stimulates interscapular brown adipose tissue temperature (T_IBAT) in male diet-induced obese (DIO) rats. What remains unclear is whether chronic hindbrain (4V) OT can impact body weight in female high fat diet-fed (HFD) rodents and whether this involves activation of brown adipose tissue (BAT). We hypothesized that OT-elicited stimulation of sympathetic nervous system (SNS) activation of interscapular brown adipose tissue (IBAT) contributes to its ability to activate BAT and reduce body weight in female high HFD-fed rats. To test this hypothesis, we determined the effect of disrupting SNS activation of IBAT on OT-elicited stimulation of T_IBAT and reduction of body weight in DIO rats. We first measured the impact of bilateral surgical SNS denervation to IBAT on the ability of acute 4V OT (0.5, 1, and 5 µg ≈ 0.5, 0.99, and 4.96 nmol) to stimulate T_IBAT in female HFD-fed rats. We found that the high dose of 4V OT (5 µg ≈ 4.96 nmol) stimulated T_IBAT similarly between sham rats and denervated rats (p = NS). We subsequently measured the effect of bilateral surgical denervation of IBAT on the effect of chronic 4V OT (16 nmol/day ≈ 16.1 μg/day) or vehicle infusion to reduce body weight, adiposity and energy intake in female HFD-fed rats (N = 7–8/group). Chronic 4V OT reduced body weight gain (sham: −18.0 ± 4.9 g; denervation: −15.9 ± 3.7 g) and adiposity (sham: −13.9 ± 3.7 g; denervation: −13.6 ± 2.4 g) relative to vehicle treatment (p < 0.05) and these effects were similar between groups (p = NS). These effects were attributed, in part, to reduced energy intake evident during weeks 2 (p < 0.05) and 3 (p < 0.05). To test whether these results translate to other female rodent species, we also examined the effect of chronic 4V infusion of OT on body weight and adiposity in two strains of female HFD-fed mice. Similar to what we found in the HFD-fed rat model, we also found that chronic 4V OT (16 nmol/day) infusion resulted in reduced body weight gain, adiposity and energy intake in female DIO C57BL/6J and DBA/2J mice (p < 0.05 vs. vehicle). Together, these findings suggest that (1) sympathetic innervation of IBAT is not necessary for OT-elicited increases in BAT thermogenesis and weight loss in female HFD-fed rats and (2) the effects of OT to reduce weight gain and adiposity translate to other female mouse models of diet-induced obesity (DIO). Full article

Glaucoma, a leading cause of blindness, is a multifactorial condition that leads to progressive loss of retinal ganglion cells (RGCs) and vision. Therapeutic interventions based on reducing ocular hypertension are not always successful. Emerging features of glaucoma include mitochondrial dysfunction and oxidative stress. In the current study, NDI1-based gene therapy, which improves mitochondrial function and reduces reactive oxygen species, was delivered intraocularly via an adeno-associated viral vector (AAV). This AAV-NDI1 therapy protected RGCs from cell death in treated (1552.4 ± 994.0 RGCs/mm²) versus control eyes (1184.4 ± 978.4 RGCs/mm², p < 0.05) in aged DBA/2J mice, a murine model of glaucoma. The photonegative responses (PhNRs) of RGCs were also improved in treated (6.4 ± 3.3 µV) versus control eyes (5.0 ± 3.1 µV, p < 0.05) in these mice. AAV-NDI1 also provided benefits in glaucomatous human lamina cribrosa (LC) cells by significantly increasing basal and maximal oxygen consumption rates and ATP production in these cells. Similarly, NDI1 therapy significantly protected H₂O₂-insulted primary porcine LC cells from oxidative stress. This study highlights the potential utility of NDI1 therapies and the benefits of improving mitochondrial function in the treatment of glaucoma. Full article

Background: Ceftriaxone upregulates GLT1 glutamate transporter in the brain and may have anti-CFC and anti-OCD effects. Methods: Twenty WZ-5HT rats were used to investigate the effects of ceftriaxone on obsessive–compulsive (OCD)-like behaviour in the marble-burying (MB) test, freezing behaviour in contextual fear conditioning (CFC) and expression of GLT1 protein in the hippocampus or amygdala using immunoblots. Fifteen DBA/2J mice were used in the MB test. We also compared diazepam with ceftriaxone in open-field, beam-walking, and wire-hanging tests on 47 DBA/2J mice. Ceftriaxone (200 mg/kg) and saline were applied intraperitoneally, once daily for 7 (rats) or 5 (mice) consecutive days. A single dose of diazepam (1.5–3.0 mg/kg) or saline was injected 30 min before the behavioural tests. Results: Ceftriaxone significantly diminished OCD-like behaviour (↓ number of marbles buried) and freezing behaviour in CFC context session (↑ latencies, ↓ total duration, ↓ duration over four 2 min periods of the session) but increased GLT1 protein expression in the amygdala and hippocampus of rats. Diazepam induced sedation, ataxia and myorelaxation in mice. Ceftriaxone did not have these side effects. Conclusions: The results of this study confirm the anti-CFC and anti-OCD effects of ceftriaxone, which did not produce the unwanted effects typical of diazepam. Full article

Dietary supplementation with n-3 polyunsaturated fatty acids (PUFA) has been found to be beneficial in rodent rheumatoid arthritis models and human trials. However, the molecular targets of n-3 PUFAs and their beneficial effects on rheumatoid arthritis are under-researched. Free fatty acid receptor 4 (FFA4, also known as GPR120) is a receptor for n-3 PUFA. We aim to investigate whether FFA4 activation reduces collagen-induced rheumatoid arthritis (CIA) by using an FFA4 agonist, compound A (CpdA), in combination with DBA-1J Ffa4 gene wild-type (WT) and Ffa4 gene knock-out (KO) mice. CIA induced an increase in the arthritis score, foot edema, synovial hyperplasia, pannus formation, proteoglycan loss, cartilage damage, and bone erosion, whereas the administration of CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA increased mRNA expression levels of pro-inflammatory Th1/Th17 cytokines, whereas CpdA significantly suppressed those increases in Ffa4 WT mice but not Ffa4 gene KO mice. CIA induced an imbalance between Th1/Th17 and Treg cells, whereas CpdA rebalanced them in spleens from Ffa4 WT mice but not Ffa4 gene KO mice. In SW982 synovial cells, CpdA reduced the LPS-induced increase in pro-inflammatory cytokine levels. In summary, the present results suggest that the activation of FFA4 in immune and synovial cells could suppress the characteristics of rheumatoid arthritis and be an adjuvant therapy. Full article

Background: Cardiomyopathies, diseases affecting the myocardium, are common causes of congestive heart failure (CHF) and sudden cardiac death. Recently, biallelic variants in ribosomal protein L3-like (RPL3L) have been reported to be associated with severe neonatal dilated cardiomyopathy (DCM) and CHF. This study employs a systems genetics approach to gain understanding of the regulatory mechanisms underlying the role of RPL3L in DCM. Methods: Genetic correlation, expression quantitative trait loci (eQTL) mapping, differential expression analysis and comparative functional analysis were performed using cardiac gene expression data from the patients and murine genetic reference populations (GRPs) of BXD mice (recombinant inbred strains from a cross of C57BL/6J and DBA/2J mice). Additionally, immune infiltration analysis was performed to understand the relationship between DCM, immune cells and RPL3L expression. Results: Systems genetics analysis identified high expression of Rpl3l mRNA, which ranged from 11.31 to 12.16 across murine GRPs of BXD mice, with an ~1.8-fold difference. Pathways such as “diabetic cardiomyopathy”, “focal adhesion”, “oxidative phosphorylation” and “DCM” were significantly associated with Rpl3l. eQTL mapping suggested Myl4 (Chr 11) and Sdha (Chr 13) as the upstream regulators of Rpl3l. The mRNA expression of Rpl3l, Myl4 and Sdha was significantly correlated with multiple echocardiography traits in BXD mice. Immune infiltration analysis revealed a significant association of RPL3L and SDHA with seven immune cells (CD4, CD8-naive T cell, CD8 T cell, macrophages, cytotoxic T cell, gamma delta T cell and exhausted T cell) that were also differentially infiltrated between heart samples obtained from DCM patients and normal individuals. Conclusions: RPL3L is highly expressed in the heart tissue of humans and mice. Expression of Rpl3l and its upstream regulators, Myl4 and Sdha, correlate with multiple cardiac function traits in murine GRPs of BXD mice, while RPL3L and SDHA correlate with immune cell infiltration in DCM patient hearts, suggesting important roles for RPL3L in DCM and CHF pathogenesis via immune inflammation, necessitating experimental validations of Myl4 and Sdha in Rpl3l regulation. Full article

Interstitial lung diseases (ILDs) are lethal lung diseases characterized by pulmonary inflammation and progressive lung interstitial scarring. We previously developed a mouse model of ILD using vanadium pentoxide (V₂O₅) and identified several gene candidates on chromosome 4 associated with pulmonary fibrosis. While these data indicated a significant genetic contribution to ILD susceptibility, they did not include any potential associations and interactions with the mitochondrial genome that might influence disease risk. To conduct this pilot work, we selected the two divergent strains we previously categorized as V₂O₅-resistant C57BL6J (B6) and -responsive DBA/2J (D2) and compared their mitochondrial genome characteristics, including DNA variants, heteroplasmy, lesions, and copy numbers at 14- and 112-days post-exposure. While we did not find changes in the mitochondrial genome at 14 days post-exposure, at 112 days, we found that the responsive D2 strain exhibited significantly fewer mtDNA copies and more lesions than control animals. Alongside these findings, mtDNA heteroplasmy frequency decreased. These data suggest that mice previously shown to exhibit increased susceptibility to pulmonary fibrosis and inflammation sustain damage to the mitochondrial genome that is evident at 112 days post-V₂O₅ exposure. Full article