Receptor Type Research Articles

B2R-D2R interaction in prolactinomas and non-functional adenomas: impact on dopamine resistance.

Prolactinomas, the most common pituitary-secreting adenomas, can be effectively treated with dopamine D2 receptor (D2R) agonists. However, a subset of them (∼20%) are resistant to dopamine (DA)-based therapies and require extirpation. The molecular mechanisms underlying their escape from dopaminergic regulation are not fully elucidated and may include alterations in D2R signaling. D2R can heteromerize with other G protein-coupled receptors, resulting in modulation of dopaminergic signaling. Since the bradykinin receptor type 2 (B2R) is overexpressed in prolactinomas, we interrogated whether this dopaminergic dysregulation observed in some prolactinomas may depend on a physical and functional interaction between D2R and B2R. The formation of B2R-D2R complexes in cultured cells transiently expressing both receptors was validated using NanoBiT technology. Interestingly, while D2R stimulation did not alter B2R-induced intracellular calcium mobilization, B2R stimulation abolished D2R signaling through modulation of cAMP. The existence of B2R-D2R complexes in pituitary adenomas (PitNet) biopsies was evaluated using an ALPHALisa approach. Importantly, B2R-D2R complexes were detected in human prolactinomas and nonfunctioning pituitary adenomas (NFPA), but not in mixed (prolactin + growth hormone) secreting adenomas. These results suggest that overexpression of B2R in resistant prolactinomas may promote the formation of B2R-D2R complexes, with B2R precluding D2R signaling, thus generating resistance to D2R agonists.

Role of local angiotensin II signaling in bladder function.

Angiotensin II signaling plays a crucial role in many different diseases. Although it has been known for several decades that local angiotensin II signaling molecules are present in the bladder, the understanding of their functions there is still limited, especially compared with other organ systems such as cardiovascular and respiratory systems. This article reviews current literature regarding local angiotensin II signaling in the urinary bladder. By reviewing several decades of literature, the field has provided strong evidence to support the presence of local angiotensin II signaling in the bladder, including the expression of angiotensin type 1 receptor and angiotensin type 2 receptor in both human and animal tissues. In addition, evidence suggests a functional role of angiotensin type 1 receptor in mediating bladder contractions. In bladder disease models, angiotensin II signaling can be upregulated, and angiotensin type 1 receptor activity is associated with increases in inflammation, fibrosis, and oxidative stress. We also address the gaps in knowledge that remain in understanding local angiotensin II signaling in the bladder, including limitations on clinical translatability. Although there is a strong foundation regarding the local presence and role of angiotensin II signaling in the bladder, further research is needed to support translational applications.

Harnessing Brain Plasticity: The Therapeutic Power of Repetitive Transcranial Magnetic Stimulation (rTMS) and Theta Burst Stimulation (TBS) in Neurotransmitter Modulation, Receptor Dynamics, and Neuroimaging for Neurological Innovations

Transcranial magnetic stimulation (TMS) methods have become exciting techniques for altering brain activity and improving synaptic plasticity, earning recognition as valuable non-medicine treatments for a wide range of neurological disorders. Among these methods, repetitive TMS (rTMS) and theta-burst stimulation (TBS) show significant promise in improving outcomes for adults with complex neurological and neurodegenerative conditions, such as Alzheimer’s disease, stroke, Parkinson’s disease, etc. However, optimizing their effects remains a challenge due to variability in how patients respond and a limited understanding of how these techniques interact with crucial neurotransmitter systems. This narrative review explores the mechanisms of rTMS and TBS, which enhance neuroplasticity and functional improvement. We specifically focus on their effects on GABAergic and glutamatergic pathways and how they interact with key receptors like N-Methyl-D-Aspartate (NMDA) and AMPA receptors, which play essential roles in processes like long-term potentiation (LTP) and long-term depression (LTD). Additionally, we investigate how rTMS and TBS impact neuroplasticity and functional connectivity, particularly concerning brain-derived neurotrophic factor (BDNF) and tropomyosin-related kinase receptor type B (TrkB). Here, we highlight the significant potential of this research to expand our understanding of neuroplasticity and better treatment outcomes for patients. Through clarifying the neurobiology mechanisms behind rTMS and TBS with neuroimaging findings, we aim to develop more effective, personalized treatment plans that effectively address the challenges posed by neurological disorders and ultimately enhance the quality of neurorehabilitation services and provide future directions for patients’ care.

Metoclopramide for analgesia in renal colic: a narrative systematic review

Metoclopramide, a prokinetic antiemetic with activity at multiple receptor types, may be a useful treatment for renal colic pain. This review investigated whether metoclopramide is an effective analgesic in the management of adults with renal colic.Eligible studies were randomised, quasi-randomised or case-control trials of metoclopramide for the management renal colic pain. Electronic database searches were performed in November 2022. Screening was performed by two authors independently; disagreement was resolved by discussion or by adjudication by a third author. The Cochrane Collaboration Risk of Bias Tool v2.0 was used to assess bias.Two studies were included, enrolling 279 patients. Heterogeneity of primary outcome measurement and comparators rendered meta-analysis inappropriate; a narrative review is presented. Both studies showed some evidence of analgesic effect. The largest study had a low risk of bias in all assessed domains, whilst the smaller study was at a high risk of bias.There is limited evidence that metoclopramide may be an effective analgesic in the management of renal colic, with the highest quality study demonstrating analgesic properties similar to an intravenous non-steroidal anti-inflammatory medication.Protocol registration Prospero (CRD42022346618).

Alamandine, a protective component of the renin-angiotensin system, reduces cellular proliferation and interleukin-6 secretion in human macrophages through MasR–MrgDR heteromerization

Alamandine (ALA) exerts protective effects similar to angiotensin (Ang) (1–7) through Mas-related G protein-coupled receptor type D receptor (MrgDR) activation, distinct from Mas receptor (MasR). ALA induces anti-inflammatory effects in mice but its impact in human macrophages remains unclear. We aimed to investigate the anti-inflammatory effects of ALA in human macrophages. Interleukin (IL)-6 and IL-1β were measured by ELISA in human THP-1 macrophages and human monocyte-derived macrophages exposed to lipopolysaccharide (LPS). Consequences of MasR–MrgDR heteromerization were investigated in transfected HEK293T cells. ALA decreased IL-6 and IL-1β secretion in LPS-activated THP-1 macrophages. The ALA-induced decrease in IL-6 but not in IL-1β was prevented by MasR blockade and MasR downregulation, suggesting MasR–MrgDR interaction. In human monocyte-derived M1 macrophages, ALA decreased IL-1β secretion independently of MasR. MasR–MrgDR interaction was confirmed in THP-1 macrophages, human monocyte-derived macrophages, and transfected HEK293T cells. MasR and MrgDR formed a constitutive heteromer that was not influenced by ALA. ALA promoted Akt and ERK1/2 activation only in cells expressing MasR–MrgDR heteromers, and this effect was prevented by MasR blockade. While Ang-(1–7) reduced cellular proliferation in MasR −but not MrgDR- expressing cells, ALA antiproliferative effect was elicited in cells expressing MasR–MrgDR heteromers. ALA also induced an antiproliferative response in THP-1 cells and this effect was abolished by MasR blockade, reinforcing MasR–MrgDR interaction. MasR–MrgDR heteromerization is crucial for ALA-induced anti-inflammatory and antiproliferative responses in human macrophages. This study broaden our knowledge of the protective axis of the RAS, thus enabling novel therapeutic approaches in inflammatory-associated diseases

The SDF-1/CXCR4 axis is involved in adipose-derived stem cell migration.

Intravenous injection of adipose-derived stem cells (ADSCs) can improve the urinary function of stress urinary incontinence (SUI) model rats and C-X-C chemokine receptor type 4 (CXCR4)-positive ADSCs are found in urethral tissues. The CXCR4 ligand stromal cell-derived factor-1 (SDF-1) is highly expressed in urinary incontinence model rats. In this study, we investigated the involvement of the SDF-1/CXCR4 axis in the homing of ADSCs. ADSCs were isolated from rats and purified. The levels of CXCR4 and CXCR7 were determined by western blot analysis and immunofluorescence assays following stimulation with SDF-1. Hypoxia conditioning was performed to treat the cells in vitro, following which the messenger RNA (mRNA) and protein level of SDF-1, CXCR4, and CXCR7 were estimated. We found that CXCR4 and CXCR7 were expressed in ADSCs at passage zero (P0), P1, and P3, and the expression of both increased after SDF-1 stimulation. The level of expression of the mRNAs and proteins of SDF-1, CXCR4, and CXCR7 in ADSCs was higher after hypoxic conditioning. We then knocked down CXCR4 or CXCR7 using small interfering RNAs and found that the mRNA levels of CXCR4 and CXCR7 were considerably downregulated in the si-CXCR4/7-transfected cells. We also found that the SDF-1/CXCR4 axis was required for the migration of ADSCs. The phosphorylation levels of Janus kinase (JAK), protein kinase B (AKT), andextracellular regulated protein kinase significantly increased in SDF-1-stimulated ADSCs. However, the migration of ADSCs was suppressed when the corresponding specific inhibitors were used to block JAK and AKT signaling or silence CXCR4, whereas no significant change was observed in the migratory ability of ADSCs when the ERK pathway was blocked or CXCR7 was silenced. The SDF-1/CXCR4 axis is involved in the migration of ADSCs and may play a role in the migrate of ADSCs in SUI.

Integrin α6β4 Upregulates PTPRZ1 Through UCHL1-Mediated Hif-1α Nuclear Accumulation to Promote Triple-Negative Breast Cancer Cell Invasive Properties

Integrin α6β4 drives triple-negative breast cancer (TNBC) aggressiveness through the transcriptional regulation of key genes. Here, we investigated how integrin α6β4 regulates protein tyrosine phosphatase receptor type Z1 (PTPRZ1). Using stable re-expression of integrin β4 (ITGB4) in cells naturally devoid of integrin α6β4 or knockdown or knockout (KO) of ITGB4, we found that integrin α6β4 regulates PTPRZ1 expression. To gain mechanistic insight, we focused on Hif-1α due to the impact of integrin α6β4 on a hypoxia-associated signature. We found that nuclear localization of Hif-1α, but not Hif-2α, was substantially enhanced with integrin α6β4 signaling. Hif-1α knockdown by shRNA or chemical inhibition decreased PTPRZ1 expression, while chemical activation of Hif-1α increased it. Upstream of Hif-1α, integrin α6β4 upregulates UCHL1 to stabilize Hif-1α and ultimately regulate PTPRZ1. Inhibition of UCHL1 and PTPRZ1 dramatically decreases integrin α6β4-mediated cell migration and three-dimensional invasive growth. Finally, public breast cancer database analyses demonstrated that ITGB4 correlates with PTPRZ1 and that high expression of ITGB4, UCHL1, HIF1A, and PTPRZ1 associated with decreased overall survival, distant metastasis free survival, post progression survival, and relapse-free survival. In summary, these findings provide a novel function of integrin α6β4 in promoting tumor invasive phenotypes through UCHL1-Hif-1α-mediated regulation of PTPRZ1.

Conditional deletion of IP3R1 by Islet1-Cre in mice reveals a critical role of IP3R1 in interstitial cells of Cajal in regulating GI motility.

Inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) has been proposed to play a physiological role in regulating gastrointestinal (GI) motility, but the underlying cell-dependent mechanism remains unclear. Here, we utilized cell-specific IP3R1 deletion strategies to address this question in mice. Conditional IP3R1 knockout mice using Wnt1-Cre, Islet1-Cre mice, and smMHC-CreEGFP were generated. Cell lineage tracing was performed to determine where gene deletion occurred in the GI tract. Whole-gut transit assay and isometric tension recording were used to assess GI function in vivo and in vitro. In the mouse GI tract, Islet1-Cre targeted smooth muscle cells (SMCs) and interstitial cells of Cajal (ICCs), but not enteric neurons. IP3R1 deletion by Islet1-Cre (isR1KO) caused a phenotype of intestinal pseudo-obstruction (IPO), evidenced by prolonged whole-gut transit time, enlarged GI tract, abdominal distention, and early lethality. IP3R1 deletion by Islet1-Cre not only reduced the frequency of spontaneous contractions but also decreased the contractile responses to the muscarinic agonist carbachol (CCh) and electrical field stimulation (EFS) in colonic circular muscles. By contrast, smMHC-CreEGFP only targeted SMCs in the mouse GI tract. Although IP3R1 deletion by smMHC-CreEGFP (smR1KO)also reduced the contractile responses to CCh and EFS in colonic circular muscles, the frequency of spontaneous contractions was less affected, and neither global GI abnormalities nor early lethality was found in smR1KO mice. IP3R1 deletion in both ICCs and SMCs but not in SMCs alone causes an IPO phenotype, suggesting that IP3R1 in ICCs plays an essential role in regulating GI motility in vivo.

Quantification of Sarcoplasmic Reticulum Ca2+ Release in Primary Ventricular Cardiomyocytes.

In the heart, ion channels generate electrical currents that signal muscle contraction through changes in intracellular calcium concentration, i.e., [Ca2+]. The cardiac ryanodine receptor type 2 (RyR2) is the predominant ion channel responsible for increasing intracellular [Ca2+] by releasing Ca2+ from the sarcoplasmic reticulum (SR). Timely Ca2+ release is necessary for appropriate cardiac function, and dysfunction can cause or contribute to life-threatening diseases such as arrhythmia. Quantification of SR-Ca2+ release in the form of sparks and waves can provide valuable insight into RyR2 opening, and factors that influence or regulate channel function. Here, we provide a series of protocols that outline processes for (1) obtaining high-quality isolated cardiomyocytes, (2) preparing samples for experimentally investigating factors that influence RyR2 function, and (3) data acquisition and analysis. Notably, our protocols leverage the potency of the recently developed myosin ATPase inhibitor, Mavacamten. This affords the opportunity to characterize the effects of small molecules or reconstituted proteins/enzymes on RyR2-Ca2+ release events across a range of [Ca2+]. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Cardiomyocyte isolation from mouse Basic Protocol 2: Preparation of cardiomyocytes for Ca2+ imaging Basic Protocol 3: Confocal microscopy and quantitative Ca2+ analysis using SparkMaster 2.

Angiotensin-II receptor type 1 and endothelin-1 receptor type A agonistic autoantibodies in patients with STEMI: new kids on the block

Abstract Background The Prognosis after ST-elevation myocardial infarction (STEMI) remains poor. Angiotensin-II and endothelin-1 contribute to adverse prognosis after STEMI through molecular mechanisms that lead to myocardial inflammation, fibrosis and, ultimately, adverse myocardial remodeling. Functional autoantibodies against angiotensin II type 1 (AT1R-AAs) and endothelin-1 type A (ETAR-AAs) receptors bind to the same receptors as natural ligands, eliciting similar (and amplified) responses. In patients with STEMI, AT1R-AAs and ETAR-AAs have been associated with a higher risk of developing microvascular obstruction and left ventricular remodeling. Both microvascular obstruction and left ventricular remodeling are associated with a poor prognosis. Purpose To assess the prognostic role of AT1R-AAs and ETAR-AAs after STEMI. Methods Consecutive STEMI patients who underwent primary percutaneous coronary intervention within 12 h after pain onset were enrolled in this prospective study. The levels of AT1R-AAs and ETAR ETAR-AAs at the time of hospital admission were measured using an enzyme-linked immunosorbent assay (ELISA) in all patients. The incidence of major adverse cardiovascular events (MACE, defined as a composite of cardiovascular mortality, myocardial re-infarction, and hospitalizations for heart failure) during follow-up was the primary outcome. Autoantibody seropositivity was defined according to ELISA’s kit manufacturer’s instructions (levels > 10 U/mL). Results Two hundred patients with STEMI were enrolled. The baseline characteristics of the patients are shown in Table 1. Of these, 110 (55%) were seronegative for both autoantibodies, 44 (22%) were seropositive for one autoantibody (but not both), and 46 (23%) were seropositive for both autoantibodies. The incidence of MACE over a 14-month median follow-up was higher in patients with double (31%) and single (25%) seropositivity than in seronegative patients (13%, p=0.009 and p=0.06, respectively). Survival free from MACE was significantly different across the different degrees of autoantibody seropositivity (Figure 1). In the multivariable Cox regression analysis, adjusted for the variables that were significant in the univariate analysis (highlighted in bold in Table 1), double seropositivity was independently associated with an increased risk of MACE (hazard ratio 2.386, 95 % CI 1.471-3.864, p<0.001). Conclusions The degree of seropositivity for AT1R-AAs and ETAR-AAs is associated with an increased risk of MACE after STEMI. Our findings provide valuable mechanistic insights into the pathophysiology of STEMI and pave the way for future therapies focused on the improvement of long-term prognosis after acute coronary syndromes.

The role of angiotensin II and endothelin receptor antibodies in COVID19 patients with HFpEF

Abstract Background The infection caused by the coronavirus SARS-COV-2, is associated with an unusual pattern of organ damage in comparison to other viral-induced pathologies. A theory of autoimmunity induced by ACE-2/SARS-COV-2 spike protein complex or its degradation products, was proposed as a possible explanation for the versatile and multiorgan damage in COVID-19. Aim The aim of the study is to determine whether antibodies against angiotensin II receptor type 1 (AT1R) or endothelin-1 receptor type A (ETAR) do exist in plasma of COVID -19 patients with heart failure with preserved ejection fraction and whether they correlate to the severity of the disease. Methods A total of 61 patients with COVID-19 and heart failure with preserved ejection fraction and 48 controls (free of COVID19) with heart failure with preserved ejection fraction were included. Patients were divided into two groups: patients with severe disease (admitted at the intensive care (n=30)), patients with milder clinical presentation that remained in the general therapeutical department (n=31). The plasma levels of IL-6 and auto-antibodies against AT1R or ETAR in peripheral blood were measured and compared between COVID19 patients with severe and milder disease and age matched controls. Clinical and standard laboratory parameters were also collected and their association with the research biomarkers was analysed. Results Auto-antibodies against AT1R were significantly increased in severe disease course (median 19.60 U/mL, IQR 4.8-34.75) compared to milder disease (median 10.95 U/mL, IQR 7.69 – 17.67, p=0.017) and the control group (median 6.79 U/mL, IQR 5.10 – 14.05, p< 0.001). ETAR antibody titers were also significantly increased in severe disease (median 14.52, IQR 6.76-32.94), compared to milder disease course (median 8.73 U/mL, IQR 6.59 –13.45, p=0.023) and to the control group (median 6.64, IQR 6.79 – 17.92, p <0.001). The same was the trend regarding IL-6 antibodies. Severe disease (median 12.11 U/mL, IQR 5.59–19.38); milder disease disease (median 8.64U/mL, IQR 1.84 – 14.13, p=0.039); control group (median 4.28U/mL, IQR 0.11–1.43, p<0.001).Both AT1R and ETAR correlated to IL-6 plasma levels. The results did not show association with the concomitant therapy. Conclusion In conclusion, we establishеd the presence of AT1R and ETAR autoantibodies in COVID-19 patients with heart failure with preserved ejection fraction. They correlated to IL-6 plasma levels (systemic inflammation) and are associated with severe form of the disease.

Oleanolic acid purified from the stem bark of Olax subscorpioidea Oliv. inhibits the function and catalysis of human 17β-hydroxysteroid dehydrogenase 1

Cancer is a leading cause of global death. Medicinal plants have gained increasing attention in cancer drug discovery. In this study, the stem bark extract of Olax subscorpioidea, which is used in ethnomedicine to treat cancer, was subjected to phytochemical investigation leading to the isolation of oleanolic acid (OA). The structure was elucidated by 1-dimensional and 2-dimensional nuclear magnetic resonance spectroscopic (NMR) data, and by comparing its data with previously reported data. Molecular docking was used to investigate the interactions of OA with nine selected cancer-related protein targets. OA docked well with human 17β-hydroxysteroid dehydrogenase type-1 (17βHSD1), caspase-3, and epidermal growth factor receptor tyrosine kinase (binding affinities: −9.8, −9.3, and −9.1 kcal/mol, respectively). OA is a triterpenoid compound with structural similarity to steroids. This similarity with the substrates of 17βHSD1 gives the inhibitor candidate an excellent opportunity to bind to 17βHSD1. The structural and functional dynamics of OA-17βHSD1 were investigated by molecular dynamics simulations at 240 ns. Molecular mechanics/Poisson-Boltzmann surface area (MMPBSA) studies showed that OA had a binding free energy that is comparable with that of vincristine (–52.76, and −63.56 kcal/mol, respectively). The average C-α root mean square of deviation (RMSD) value of OA (1.69 Å) compared with the unbound protein (2.01 Å) indicated its high stability at the protein’s active site. The binding energy and stability at the active site of 17βHSD1 recorded in this study indicate that OA exhibited profound inhibitory potential. OA could be a good scaffold for developing new anti-breast cancer drugs.

RKER-012, a novel modified ActRIIB ligand trap, attenuated right ventricular cardiomyopathy in a preclinical model of pulmonary arterial hypertension

Abstract Background The primary cause of death in pulmonary arterial hypertension (PAH) is right ventricular (RV) failure. Initially, the RV adapts to heightened pressure through adaptive remodeling, but prolonged pressure overload triggers maladaptive remodeling, culminating in failure. Overactive activin/growth differentiation factor (GDF) signaling has been implicated in cardiomyopathy and heart failure. RKER-012, a research version of KER-012, is an investigational modified activin receptor type IIB (ActRIIB) ligand trap designed to specifically bind and inhibit select TGF-β ligands, including activins A and B and GDFs 8 and 11. RKER-012 previously exhibited a cardioprotective effect in a pulmonary arterial banding (PAB) model of RV dysfunction. To determine the effect of RKER-012 on afterload-induced RV cardiomyopathy caused by increased pulmonary artery pressure, we utilized an angio-obliterative Sugen/hypoxia (SH) rat model of PAH that closely mimics human PAH pathology. Methods Male Sprague Dawley rats were subcutaneously (s.c.) injected with one dose of Sugen 5416 and exposed to 10% hypoxia for 3 weeks during which they received either vehicle (SH-Veh; s.c; BIW) or RKER-012 (10 mg/kg; s.c; BIW). Normoxic (Nx) control rats were maintained in room air for 3 weeks with BIW s.c. vehicle treatment. After 3 weeks of treatment, systolic pulmonary arterial pressure (sPAP) and Fulton index (FI) were assessed. Hallmark genes of inflammatory process, endothelial/platelet activation, and fibrosis were evaluated in the RV by qPCR. Results Increases in FI (+99.4%;p<0.0001) and sPAP (+250.9%;p<0.0001) were observed in SH-Veh rats vs. Nx rats, consistent with the development of pulmonary and cardiac impairment. In contrast, treatment with RKER-012 reduced FI (-28.0%;p<0.001) and sPAP (-44.5%;p<0.001). In the RV, SH-Veh rats had increased expression of TGF-ß pathway genes involved in inflammation, endothelial/platelet activation, and fibrosis. RKER-012 treatment reduced expression of these genes (Tgf-β1, -44.7%;p=0.003; Fstl3, -43.5%;p=0.0162; Mcp1, -22.5%;p=0.535; Cd68, -60.3%;p=0.0048; Ctgf, -57.1%;p=0.0139; Col1a1, -47.2%, p=0.0255 ;Col3a1, -69.5%;p<0.0001; Lox, -61.4%;p=0.0054; P-selectin, -63.9%;p=0.018) in comparison to SH-Veh treatment. Conclusion Consistent with previous findings in a PAB mouse model, RKER-012 treatment protected against increased sPAP and maladaptive cardiac remodeling in a SH rat model of PAH. Additionally, RKER-012 attenuated RV cardiomyopathy by reducing the expression of genes involved in inflammatory and fibrotic processes. These preclinical findings in the RV paralleled the changes in circulating cardiovascular health biomarkers, including reduced NT-proBNP, observed in a Phase 1 trial of KER-012 in healthy volunteers. These findings, along with the safety and tolerability observed in the Phase 1 trial, provided rationale for the ongoing Phase 2 TROPOS trial of KER-012 in patients with PAH (NCT05975905).

Therapeutic potential of EVs loaded with CB2 receptor agonist in spinal cord injury via the Nrf2/HO-1 pathway

ABSTRACT Background Spinal cord injury (SCI) poses a challenge due to limited treatment options. Recently, the effect and mechanism of Exo-loaded cannabinoid receptor type 2 (CB2) agonist AM1241(Exo + AM1241) have been applied in other inflammatory diseases but not in SCI. Methods The SCI model was set up using C57BL/6 mice, followed by the treatment of Exo, AM1241, and Exo + AM1241. We assessed the effects of the following treatments on motor function recovery using BMS, and evaluated histological changes, apoptosis activity, inflammation, and oxidative stress in the SCI mice model. Additionally, the effect of following treatments on spinal cord neural stem cells (NSCs) was evaluated under lipopolysaccharides (LPS) induced inflammatory and oxidative models and, glutamate (Gluts) induced cell apoptosis models. Result Our results demonstrated that Exo + AM1241 treatment significantly improved motor function recovery, after SCI by decreasing proinflammatory cytokines, and suppressing astrocyte/microglia (GFAP/Iba1) activation in the injury zone. Additionally, this treatment reduces pro-apoptotic proteins (Bax and caspase 3), increases the levels of the anti-apoptotic protein Bcl-2, enhances antioxidant defenses by boosting SOD and GSH, and lowers oxidative stress markers such as MDA. It also activates the Nuclear factor erythroid-2 (Nrf2) related factor 2 signaling pathway, thereby enhancing tissue protection against damage and cell death.

Recruitment of CCR5-positive T cells in pulmonary vascular lesions in idiopathic- and connective tissue disease associated- pulmonary arterial hypertension

Abstract Background C-C chemokine receptor type 5 (CCR5) is a chemokine receptor predominantly expressed on leukocytes including T cells, macrophages, and dendritic cells, and is involved in the process by which T cells are attracted to specific tissues and organs. Although CCR5 has been shown to be expressed on macrophages and pulmonary artery smooth muscle cells in lung samples from human idiopathic pulmonary arterial hypertension (PAH) and some animal models, its expression on T cells in human PAH lungs has not been investigated. Purpose To investigate the immunohistochemical expression of CCR5 on T cells infiltrating in pulmonary vascular lesions of human PAH tissues, particularly from patients with idiopathic PAH and PAH associated with connective tissue disease (CTD-PAH), where inflammation has been implicated in the pathogenesis. Methods Subjects included 25 postmortem cases of idiopathic PAH (14 cases, a mean age of 34 ± 10 years, 8 female cases) and CTD-PAH (11 cases, 48 ± 13 years, all female). We performed immunohistochemistry using antibodies against CCR5 and CD3 (for T cells) on formalin-fixed paraffin-embedded sections. To semi-quantify, we selected the three small muscular pulmonary arteries (80-150 µm in external diameter) with the strongest CCR5-positive cell infiltration in each case, counted the number of positive cells, and the average were shown as the number of cells per vessel. Results In all cases, regardless of whether IPAH or CTD-PAH, a subset of infiltrating inflammatory cells into or accumulating around vessels was CCR5-positive. Specifically, CCR5-positive inflammatory cells were found in remodelled pulmonary arteries, such as plexiform lesions and constrictive lesions with intimal thickening and/or medial hypertrophy, as well as perivascular space. The average number of CCR5-positive cells per small muscular pulmonary artery was 8.1/vessel. Where pulmonary venous occlusive lesions were seen, CCR5-positive cells were also present in and around them. The majority of CCR5-positive inflammatory cells appeared to be T cells, based on morphology and CD3 immunopositivity in the serial sections. Conclusion(s) Activated T cells showing CCR5 immunopositivity were recruited to remodelled pulmonary vascular lesions in both idiopathic PAH and CTD-PAH. This implicates CCR5-positive T cells as a common key player and that CCR5 signalling is involved in the pathogenesis of PAH in concert with other inflammatory cells, vascular endothelial cells, and pulmonary artery smooth muscle cells.

Antagonistic CLE peptide pathways shape root meristem tissue patterning.

Secreted CLAVATA3/EMBRYO SURROUNDING REGION (CLE) peptide ligands dimension the stem cell niche of Arabidopsis shoot meristems by signalling through redundant and cross-compensating CLAVATA1 (CLV1)-type receptor kinases. In the root meristem, the CLV1 homologues BARELY ANY MERISTEM 1 (BAM1) and BAM2 drive CLE13/16-mediated formative divisions that produce the ground tissue layers. Here we report that BAM1/2 are also required to initiate the vascular phloem lineage and that cross-compensation between CLV1-type receptors as observed in the shoot does not operate similarly in the root. Rather, we find that BAM3-mediated CLE45 signalling antagonizes BAM1/2-mediated CLE11/12/13 signalling in the phloem initials but not in the ground tissue. We further observe spatiotemporally contrasting CLE signalling requirements for phloem initiation and differentiation, which are shaped by the SHORT ROOT (SHR) pathway. Our findings thus suggest an intricate quantitative interplay between distinct and antagonistic CLE signalling pathways that organizes tissue layer formation in the Arabidopsis root meristem.

Opioid receptor and dopaminergic gene expression increase in the brains of dominant medaka Oryzias latipes males after repeated fights.

The central opioid system and dopaminergic activity in mammals play key roles in mediating social reward, impulsivity, cognition, decision making, and motivation for learning and social interactions. Repeated positive fighting experiences enhance the gene expression levels of μ-type opioid receptor (Mor), tyrosine hydroxylase (Th), an enzyme involved in dopamine synthesis, and dopamine receptor type 2 (D2r) in the reward-related brain regions of aggressive mice. However, it remains unclear whether the opioid system and dopaminergic activity are associated with repeated winning in fish. In this study, we investigated changes in the expression levels of Mor, Th1, and D2r in different regions of the brain of adult medaka Oryzias latipes males after intermittent and continuous fight for 3 days. When a pair of males was provided a fighting opportunity for 20 min per day, we noted that within the 3-day observation period, aggressive winning males showed significantly higher expression levels of Mor in telencephalon and diencephalon, Th1 in diencephalon, and D2r in telencephalon than subordinate losing males. However, no such differences in gene expression level were observed between winning and losing males in the 3-day continuous fight. Further, no differences were detected in the total number of aggressive actions among the winners from each fighting test. However, the total number of "chase" actions, with a stronger aggressiveness index, was higher for the repeated winning male in the three-time intermittent fight than for the winner in the 3-day continuous fight. These findings suggest that repeated intermittent winning experiences with strong aggressiveness could be perceived as a reward by O. latipes males.

The Selective Endothelin Receptor Antagonist SC0062 in IgA Nephropathy: A Randomized Double-Blind Placebo-Controlled Clinical Trial.

Key Points Patients with IgA nephropathy and significant proteinuria are at high risk of progressive kidney function loss and kidney failure.We report the results of a clinical trial assessing the selective endothelin receptor antagonist SC0062 for the treatment of IgA nephropathy.SC0062 led to clinically meaningful improvements in proteinuria and did not increase risk of peripheral edema at higher doses. Background Endothelin receptor type A activation contributes to kidney injury in patients with IgA nephropathy. SC0062 is a novel selective endothelin receptor type A antagonist. We report the results of a phase 2 dose-finding trial to characterize the efficacy and safety of SC0062 in patients with IgA nephropathy. Methods We conducted a randomized, placebo-controlled, double-blind, clinical trial in adults with biopsy-proven IgA nephropathy and eGFR ≥30 ml/min per 1.73 m2 with urinary protein-creatinine ratio (UPCR) ≥0.75 g/g or proteinuria ≥1 g/24 hour despite using maximum tolerated doses of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Patients were randomized 1:1:1:1 to 24-week treatment with SC0062 5, 10, and 20 mg or matching placebo once daily. The primary efficacy outcome was percent change from baseline in UPCR in 24-hour urine samples after 12 weeks of treatment. Secondary end points included changes in eGFR. Safety outcomes including treatment emerging adverse events and serious adverse events were recorded. Results Overall, 131 patients (mean age 42 years [SD, 11]; mean eGFR 72 ml/min per 1.73 m2 [SD 24] and median 24-hour UPCR 1.2 g/g [25th–75th percentile, 0.9–1.5 g/g]) were randomized to placebo (n=34) or SC0062 5 mg (n=33), 10 mg (n=32), or 20 mg (n=32). All SC0062 doses reduced UPCR versus placebo throughout treatment. At week 12, placebo-corrected geometric mean changes (95% confidence interval) from baseline in UPCR with SC0062 5, 10, and 20 mg were−27.6% (−43.0 to −8.2), −20.5% (−37.4 to 1.0), and −38.1% (−51.4 to −21.0), respectively, and at week 24 they were−22.4% (−42.2 to 4.3), −30.9% (−48.6 to −7.0), and −51.6% (−64.2 to −34.6), respectively. No differences in eGFR were observed among treatment groups. The proportion of participants with treatment emerging adverse events or serious adverse events was balanced among treatment groups. Peripheral edema was reported by 2 (6%), 1 (3%), 1 (3%) participants in the 5, 10, and 20 mg SC0062-treated groups, respectively, compared with 5 (15%) in the placebo group. Conclusions In patients with IgA nephropathy, SC0062 reduced proteinuria and did not increase risk of peripheral edema. Clinical Trial registry name and registration number: A Study to Evaluate the Efficacy and Safety of SC0062 in the Treatment of CKD, NCT05687890.

Fibrodysplasia ossificans progressiva: a comprehensive review

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder that causes heterotopic ossification of soft tissues, leading to abnormal bone growth in muscles, tendons, and ligaments. First identified in the 17th century, FOP was classified in 1968 and is linked to a mutation in the Activin A receptor type I gene (ACVR1) which affects bone morphogenetic protein (BMP). The autosomal dominant condition FOP has the potential to lead to aberrant bone development. At birth, FOP individuals appear normal, except for characteristic malformations of the great toes. FOP patients develop painful, inflammatory soft tissue swellings during the first decade of life, often precipitated by soft tissue injury. Minor trauma can trigger new flare-ups and leads to progressive heterotopic ossification. Most FOP sufferers are wheelchair-bound by their third decade and needs lifelong assistance with daily living tasks. Bone morphogenetic proteins (BMPs) are bound by the transmembrane kinase receptor ALK2, which is encoded by the (ACVR1/ALK2 gene). FOPs induce heterotopic bone formation in skeletal muscle and can be caused by mutations in the activin A receptor type I (ACVR1) and activin-like kinase 2 (ALK2) gene. Clinical therapy focuses on preventing and controlling inflammation, with ongoing research focusing on specific therapies targeting receptor activity, aberrant pathways, or cellular components influencing bone neo-formation.

Identification of umami peptides and mechanism of the interaction with umami receptors T1R1/T1R3 in pigeon meat.

Pigeon meat offer an ideal source for extracting fresh flavor peptides. These peptides not only enhance the taste of food but also have potential health benefits, including providing low-sugar, low-sodium, and low-calorie options for individuals with conditions like diabetes, hypertension, and obesity. Therefore, further research into the pigeon industry holds promise for addressing both economic and nutritional needs. To explore umami peptides and their molecular binding mechanisms with umami receptor type 1 member 1 in pigeon meat, an enzymatic hydrolysate product is isolated, analyzed, and subjected to sensory evaluation. Fifteen peptides with high freshness characteristics are separated and identified by ultrafiltration, gel separation, reverse performance liquid chromatography, and nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS). The molecular docking results show that the amino acid residue Glu128 is a common ligand binding site for all of the fresh-flavored peptides to taste T1R1/T1R3 receptors and it exerts freshness-presenting effects with 15 fresh-flavored peptides through hydrogen bonding, electrostatic interactions, salt bridges, and hydrophobic interactions. This study provides a theoretical basis and technical support for the subsequent development of flavor peptide products in pigeon meat.