Receptor Beta Research Articles

Nephro- and Cardiotoxic Effects of Etoricoxib: Insights into Arachidonic Acid Metabolism and Beta-Adrenergic Receptor Expression in Experimental Mice

Background: Etoricoxib is a widely used anti-inflammatory drug, but its safety profile concerning cardiovascular and renal health remains inadequately explored. This study aimed to assess the nephro- and cardiotoxic effects of etoricoxib in a murine model, with a focus on its impact on arachidonic acid-metabolizing enzymes and beta-adrenergic receptors associated with drug-induced toxicity. Methods: Thirty-five BALB/C mice were randomly assigned to five groups: control, low-dose etoricoxib, high-dose etoricoxib, low-dose celecoxib, and high-dose celecoxib (a well-known nephro- and cardiotoxic NSAID). The treatments were administered for 28 days, after which hearts and kidneys were excised for physical and histopathological analysis, and the expression of arachidonic acid-metabolizing enzymes (cytochrome P450s, lipoxygenases, cyclooxygenases) and beta-1 adrenergic receptor (adrb1) and angiotensin-converting enzyme (ace2) genes were quantified using quantitative reverse transcription PCR (qRT-PCR). Results: Etoricoxib administration resulted in dose-dependent nephro- and cardiotoxic effects. Renal histology revealed glomerular atrophy or hypertrophy and significant damage to the proximal and distal convoluted tubules, including epithelial flattening, cytoplasmic vacuolation, and luminal widening. Cardiac analysis showed disorganized muscle fibers and hyaline degeneration. These changes were associated with altered gene expression: the downregulation of cox2, cyp1a1, and cyp2c29 in the kidneys and the upregulation of cyp4a12, cox2, and adrb1, along with the downregulation of cyp2c29 and ace2 in the heart. Conclusions: Etoricoxib induces nephro- and cardiotoxicity, marked by alterations in arachidonic acid metabolism and beta-adrenergic signaling pathways. The drug affects the expression of arachidonic acid-metabolizing enzymes and adrb1 in the heart while downregulating cox2 and other related enzymes in the kidneys. These findings underscore the need for caution when prescribing etoricoxib, particularly in patients with pre-existing renal or cardiac conditions.

Innovative Approach of High-Throughput Screening in the Drug Discovery Quest for Chronic Bronchitis Treatment

Chronic bronchitis (CB) is a challenging condition that worsens over time. Patients continue to experience an abundance of symptoms despite their best attempts to manage them. The etiology of CB is goblet cell overproduction and mucus hypersecretion, which aggravates airflow obstruction by luminal blockage of small airways, epithelial remodeling and modification of airway surface tension that predisposes to collapse. Larger randomized controlled trials are required to validate the pilot data that are currently accessible and assess the treatment’s durability as therapies are still in the early stages of clinical development. To overcome the prevailing increase in CB with the rise in air pollution globally, this study proposes a de novo drug discovery candidate for the effective treatment of CB. With the aid of cutting-edge technology of high-throughput screening, a phytochemical, apigenin, has been administered to target the Beta-2 adrenergic receptor protein and utilized as an exemplary ligand to target the discovery of a suitable drug candidate for Beta-2 adrenergic receptor protein. The drug likeness scores, no evident toxicity and binding affinity –9.092 kcal/mol the “CHEMBL294878” proves to be a potential drug candidate discovered for CB. A therapeutic drug specifically meant to treat CB can be developed with the help of the computational data provided by the research presented in this study.

Survival Distinctions for Cases Representing Immunologically Cold Tumors via Intrinsic Disorder Assessments for Blood-Sourced TRB Variable Regions

T cell receptor beta (TRB) sequences were recovered from the Cancer Genome Atlas Uveal Melanoma blood exome files. Intrinsic disorder scores for amino acid (AA) sequences of the entire TRB variable region were obtained and evaluated as potentially representative of overall survival (OS) distinctions, i.e., for cases representing the upper and lower 50th percentiles for intrinsic disorder scores. Analyses using four intrinsic disorder assessment tools indicated that a lower intrinsic disorder of the blood-sourced TRB variable regions, including continuous AA sequences of the V-gene segment, the complementarity-determining region-3, and the J-gene segment, was associated with a better OS probability (with log-rank p-values ranging from 0.002 to 0.014). We further determined that intrinsic disorder assessments could be used for OS stratification for a second, immunologically cold cancer: MYCN amplified neuroblastoma. Thus, intrinsic disorder assessments of blood-sourced, full TRB variable regions may provide a novel patient stratification approach for patients with immunologically cold cancers.

Mild hypercapnia before reperfusion reduces ischemia-reperfusion injury in hyperacute ischemic stroke rat model.

Endovascular thrombectomy has a recanalization rate over 80%; however, approximately 50% of ischemic stroke patients still experience dependency or mortality. Recently, clinical trials demonstrated the benefits of administering neuroprotective agents prior to endovascular thrombectomy. Additionally, recent studies showed neuroprotective effects of mild hypercapnia in patients resuscitated after cardiac arrest. However, its efficacy in ischemic stroke remains unclear. We aimed to investigate whether carbon dioxide (CO2) per-conditioning has neuroprotective effects in rat models with middle cerebral artery occlusion (MCAO). Rat models received intermittent inhalation of mixed gas during the MCAO period. After surgery, behavioral assessments, infarct size measurement, immunohistochemistry, and western blot analysis were performed. We found CO2 per-conditioning reduced infarct size and neurological deficit. The number of 8-hydroxy-2-deoxyguanosine (8-OHdG) positive cells and matrix metalloproteinase 9 (MMP-9)/platelet derived growth factor receptor beta (PDGFRβ) double positive cells were significantly decreased after CO2 per-conditioning. The expressions of tight junction protein and pericytes survival were preserved. This study underscores mild hypercapnia before reperfusion not only reduces neurologic deficit and infarct size, but also maintains the integrity of the blood-brain barrier and neurovascular unit, alongside mitigating oxidative stress in hyperacute stroke rat models. Therapeutic mild hypercapnia before reperfusion is promising and requires further clinical application.

The Effects of Nebivolol-Gefitinib-Loratadine Against Lung Cancer Cell Lines.

Non-small-cell lung cancer (NSCLC) is the most frequently diagnosed malignancy and the first cause of cancer-related death. Thus, finding alternative therapeutic options is crucial. Drug repurposing offers therapeutic options in a simplified and affordable manner, especially to cancer patients in developing countries. Several drugs including antihistamines and beta-adrenergic receptor blockers (beta-blockers) display antiproliferative properties on cancer cells. Interestingly, NSCLC patients who had used either antihistamines or beta-blockers showed improved response to chemotherapy or reduced mortality in comparison to non-users of any of these drugs. However, combination therapy is gaining substantial interest in many cancers including non-EGFR mutated NSCLC. Here, we investigated the antineoplastic effect of the combination of the antihistamine loratadine, the beta-blocker nebivolol, and the tyrosine-kinase inhibitor gefitinib on NSCLC cell lines. A-549 and NCI-H1975 cell lines were used. The effect of nebivolol, gefitinib, and loratadine on the metabolic activity was studied using the MTT assay. The inhibitory concentrations (IC20 and IC50) were calculated and used in the drug-combination experiments. Apoptosis was investigated using flow cytometry; and cell survival using the colony formation assay. The combination nebivolol-loratadine-gefitinib produced a significant synergistic effect on inhibiting the metabolic activity and colony formation, as well as on promoting apoptosis in both cell lines. Noteworthy, the effect on the cell line carrying the EGFR mutation (NCI-H1975) was very similar to the cell line that does not exhibit such mutation (A-549 cells). The nebivolol-gefitinib-loratadine combination may be a promising alternative for lung cancer treatment.

Single-cell transcriptomic analysis reveals dynamic activation of cellular signaling pathways regulating beige adipogenesis.

PDGFRA+ cells have been identified as adipocyte stem cells (ASCs) that differentiate into beige adipocytes in white adipose tissue (WAT) following thermogenic stimuli. To elucidate the molecular heterogeneity of ASCs, we conducted single-cell transcriptomic profiling of PDGFRA+ cells isolated from the inguinal WAT (iWAT) of mice treated with the beta3 adrenergic receptor agonist CL316243. Single-cell RNA-seq revealed nine major clusters, which were categorized into four groups: resting, proliferating, differentiating, and adipogenic factor-expressing cells (AFECs). Trajectory analysis revealed sequential activation of molecular pathways, including the Hedgehog and Notch signaling pathways, during beige adipogenesis. AFECs expressed Dpp4 and did not differentiate into adipocytes in culture or after transplantation. Furthermore, genetic lineage tracing studies indicated that DPP4+ cells did not differentiate into adipocytes in iWAT during CL316243-induced beige adipogenesis. However, high-fat diet feeding led to the recruitment of adipocytes from DPP4+ cells in iWAT. Overall, this study improved our understanding of the dynamic molecular basis of beige adipogenesis and the potential contribution of DPP4+ adipocyte lineages to the pathological expansion of WAT during diet-induced obesity.

Carvedilol suppresses coronary artery spasm in A-kinase anchoring protein 150 knockout mouse

Abstract Backgrounds A-kinase anchoring proteins (AKAPs) act as scaffold to regulate activation of protein kinases and subsequent downstream signaling. AKAP 150 interacts with protein kinase A and protein kinase C, and has a critical role in regulating L-type calcium channel activity. We previously reported enhanced phospholipase C activity as an important mechanism of coronary spastic angina (CSA), known as Prinzmetal’s angina. Coronary artery spasm was induced by intravenous ergometrine injection in mouse model of vascular smooth muscle cell (VSMC)-specific enhanced phospholipase C activity concomitantly with enhanced intracellular Ca2+ concentration ([Ca2+]i). Then, we hypothesized that coronary artery spasm would be inhibited by AKAP 150 knockout, however, coronary artery spasm was unexpectedly induced in AKAP 150 knockout (AKAP-KO) mice without affecting [Ca2+]i, suggesting that AKAP-KO mouse is an unique model of CSA independent of [Ca2+]i. Previous report showed that AKAP-KO mice have a high Ca2+/calmodulin-dependent protein kinase (CaMK) II activity, and carvedilol, a non-selective beta-adrenergic receptor antagonist, inhibits CaMK II activity. Aim We tested the hypothesis that carvedilol could prevent coronary artery spasm via inhibiting CaMK II activity, which is a key molecule to regulate VSMC contraction, in AKAP-KO mice. Methods and Results We pretreated 14-18-weeks-old AKAP-KO mice with intraperitoneal injection of carvedilol (2.5mg/kg), propranolol (20mg/kg), or vehicle (control). Coronary artery spasm, evaluated by ST-segment elevation on lead II of body surface electrocardiogram, was induced by intravenous ergometrine injection (30mg/kg) in all controls (5/5, 100%) and all propranolol-treated mice (5/5, 100%), whereas it tended to be inhibited in carvedilol-treated mice (3/6, 50%) (p=0.08 vs control). In isolated VSMCs obtained from the aorta of AKAO-KO mice, the changes in [Ca2+]i from baseline in response to acetylcholine (ACh, 100μM) did not differ among the groups of pretreatment with carvedilol (10μM), propranolol (10μM), or vehicle, indicating that coronary artery spasm in AKAP-KO mice was induced by Ca2+-independent mechanism. In response to ACh, the phosphorylation of CaMK II was tended to be decreased (p=0.07), and the phosphorylation of myosin light chain was decreased (p<0.05) in VSMCs treated with carvedilol compared with control. Conclusions Carvedilol may inhibit coronary artery spasm probably via inhibiting CaMK II activity in AKAP-KO mice. Our results may provide a new paradigm into the pathogenesis of CSA as a model of enhanced Ca2+ sensitivity and important clinical implications for the mechanism of calcium channel antagonist-refractory coronary artery spasm.

Evaluation of 18F FOL a PET tracer targeting folate receptor beta in a rat model of myocardial infarction

Abstract Background Expression of folate receptor-β (FR-β) on the activated macrophages is associated with inflammatory diseases. However, the role of FR-β in the immune response following myocardial infarction (MI) remains unknown. Purpose To investigate FR-β-targeted positron emission tomography (PET) tracer aluminium fluoride-18-labeled 1,4,7,-triazacylononane-1,4,7-triacetic acid conjugated folate ([18F]FOL) for imaging immune response in a rat model of MI. Methods Rats underwent PET scan from 20 to 40 minutes after injection of 50±6 MBq of [18F]FOL on 3 (n=6), 7 (n=21), 15 (n=9), and 90 (n=11) days after surgical ligation of the left coronary artery. As controls, rats were studied on 3 (n=6), 7 (n=14), 15 (n=5), and 90 (n=8) days after sham-operation. [18F]FDG PET was performed a day before [18F]FOL injection in order to localize myocardium and area of MI. After [18F]FOL PET, autoradiography, histology, and staining of CD68 were performed 3 (n=6), 7 (n=6), and 90 (n=11) days after MI in order to detect [18F]FOL uptake and activated macrophages in myocardial tissue sections. A subgroup of rats (n=15) underwent serial [18F]FOL PET 7 and 90 days after MI together with echocardiography in order to evaluate left ventricular function. Results The presence of MI was confirmed by histology in all rats after coronary ligation. PET images showed increased uptake of [18F]FOL in the area of MI. The uptake was significantly higher (p<0.001) in the area of MI than in the myocardium of sham-operated rats on day 3 (SUV 2.04±0.25 vs. 0.74±0.12), and remained increased on day 7 (SUV 1.39±0.33 vs. 0.68±0.12), day 15 (SUV 1.24±0.20 vs. 0.59±0.07), and day 90 (SUV 1.39±0.25 vs. 0.69±0.11). On day 3, pre-treatment with folate glucosamine (n=3) reduced the [18F]FOL signal by 50% in the area of MI indicating specific binding to FR-β. Autoradiography confirmed focally increased uptake of [18F]FOL in the area of MI. A positive correlation was found between uptake of [18F]FOL in PET images and areal percentage of CD68-positivity in the area of MI (r2=0.447, p<0.001). Uptake of [18F]FOL on day 7 after MI was associated with decline in left ventricular ejection fraction (R=-0.665, p<0.01) and increase in left ventricular systolic volume (R=0.561, p=0.02) between 7 and 90 days after MI. Conclusion Cardiac [18F]FOL PET detects increased macrophage-associated FR-β expression after MI in a rat model. FR-β expression peaks early and remains elevated up to 3 months in the infarcted area. Increased FR-β expression early after MI is associated with worsening of left ventricular systolic function late after MI.

Gamma irradiation green synthesis of (polyacrylamide/chitosan/silver nanoparticles) hydrogel nanocomposites and their using as antifungal against Candida albicans and anti-cancer modulator

Silver nanoparticles-loaded hydrogel nanocomposites are exploited for medicinal and pharmaceutical applications. Hydrogel nanocomposites were prepared from acrylamide (Am), chitosan (CS) and AgNO3 utilizing gamma rays. Diverse variables were applied in preparation of silver nanoparticles-laoded hydrogel nanocomposites of (PAm/CS)-AgNPs such as influence of radiation dose and influnece of CS concentration. Diverse techniques were utilized to characterize hydrogel nanocomposites; Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), X-ray diffraction (XRD), Transmission electron microscopy (TEM), energy dispersive X-ray (EDX) and scanning electron microscopy (SEM). Results confirmed formation of silver nanoparticles-loaded hydrogel nanocomposites of (PAm/CS)-AgNPs. Antifungal activity of (PAm/CS)-AgNPs hydrogel nanocomposites on viability of C. albicans was esitmated. Results displayed the efficient microbial inhibition activity of treatment against C. albicans compared to control. Furthermore, (PAm/CS)-AgNPs hydrogel nanocomposite against cervical cancer HeLa cell line was investigated. Cytotoxicity of (PAm/CS)-AgNPs hydrogel nanocomposites on prior cancer cell line empolyed to prohibition of cell growth assesssed by MTT test. HeLa cancer cell is treated by (PAm/CS)-AgNPs for 48 h exposed a potential apoptotic activity by noticeable up-regulation of p53 gene expression. Moreover, anticancer activity was investigated by down-regulation of platelet-based growth variable receptor beta (PDGFR-β), Bcl2, Cathepsine, and MMP-2 gene expression. antioxidant activity was investigated and results showed antioxidant activity of (PAm/CS) hydrogel and (PAm/CS)-AgNPs hydrogel nanocomposite are 87.8% and 62.9%, respectively.

Tumor Differentiation is Correlated with Estrogen Receptor Beta (ERβ) Expression but Not with Interleukin-6 (IL-6) Expression in Colorectal Carcinoma

BACKGROUND: Colorectal carcinoma (CRC), the third most common malignant disease worldwide, is associated with estrogen receptor β (ERβ) and interleukin-6 (IL-6). ERβ is known to down-regulate IL-6 in prostate cancer, lung carcinoma, and CRC cell lines; however, its effect on human with CRC remains unclear. Therefore, this study was conducted to investigate the association between ERβ and IL-6 expressions with the clinicopathological features of CRC.METHODS: This was an analytic observational study using 40 paraffin blocks of CRC patients. ERβ and IL-6 expression was measured by immunohistochemistry (IHC) staining. The percentage of immunoreactive tumor cell per 1000 cells was manually recorded and tumor differentiation as well as tumor infiltration were determined. Tumor differentiation was graded according to the World Health Organization (WHO) 2010 criteria, while tumor infiltration was defined based on the American Joint Committee on Cancer (AJCC) 8th edition.RESULTS: Fifty percent of samples were well-differentiated CRC, and 57.5% samples were T3 infiltration tumors. IHC staining showed 35.5% of samples were positive for ERβ expression, while 70.86% were positive for IL-6 expression. There were negative correlation of ERβ expression with tumor differentiation (p=0.018; r=-0.371), but no correlation with tumor infiltration (p=0.836) were found. There was no correlation between ERβ expression with IL-6 expression (p=0.154).CONCLUSION: There is statistically significant correlation between tumor differentiation and ERβ expression, wherein improved tumor differentiation is linked to higher levels of positive ERβ expression. However, there is no discernible relationship between IL-6 and tumor differentiation. These findings suggest that while IL-6 was involved in the growth of the tumor, ERβ expression might have an impact on tumor differentiation.KEYWORDS: colorectal carcinoma, estrogen receptor beta, interleukin-6, cell differentiation

High Levels of Uric Acid Upregulate Endothelin Receptors: The Role of MAPK Pathways in an in vitro Study

IntroductionUric acid (UA) is the end product of purine compounds' metabolism. There is overwhelming evidence linking hyperuricemia (high levels of UA) and cerebrovascular diseases, but the effect of high levels of UA on cerebral vessels is not fully understood. The aim of this research is to clarify how UA affect the endothelin (ET) receptor in rat cerebral arteries and the related mechanism.Material and methodsIn an in vitro setting, segments of rat cerebral arteries (n=12) were exposed to high levels of UA, either alone or in conjunction with MAPK pathway inhibitors. ET agonists were used to induce contractions that were then measured with a myograph. ET receptor expression was measured using RT-PCR (n=6), Western Blot (n=3), or immunohistochemistry (n=3) to quantify mRNA and protein levels.ResultsThe study revealed that high levels of UA notably increase ETA and ETB receptor-induced contractions and boost the expression of ET receptors in cerebral arteries when compared to that are fresh or cultured alone, suggesting that UA enhances ETA and ETB receptors. Additionally, the up-regulation of ETB receptors induced by UA was inhibited by the p38 inhibitor SB203580, the JNK inhibitor SP600125, and the ERK1/2 inhibitor U0126. SB203580 significantly blocked the increase in ETA receptor-mediated contractions induced by UA and the upregulation of ETA receptor. Neither SP600125 nor U0126 had such effect.ConclusionsHigh levels of UA stimulate the up-regulation of ET receptors in rat cerebral arteries in vitro through MAPK pathways. This study may offer novel perspectives on hyperuricemia-associated cerebrovascular diseases.

Topical application of beta-blockers accelerates epithelialization to mesh skin grafted full-thickness burn in sheep

Aim : Beta-adrenergic receptor blockers are conventionally used for the treatment of hypertension, tachycardia, and glaucoma. Research has shown that beta-blockers can accelerate wound epithelialization. In this study, we tested the efficacy of the beta-blocker timolol in an ovine model of grafted full-thickness burn wound healing, which closely mimics clinical scenarios. Methods : Six full-thickness burn wounds were created on the sheep’s posterior surface. Twenty-four hours later, eschars were excised and meshed skin was grafted (Day0). The wounds in the treatment group received topical application of timolol. Blood flow was measured using a blood perfusion imager. Cardiovascular hemodynamics and blood glucose levels were recorded daily. The epithelialization rate on Day 14 was determined by planimetric assay and analyzed by paired t -test. The days that the epithelialization rate exceeded 85%, 90%, and 95% were analyzed by survival analysis. To assess the potential influence of TGFβ, epithelial-mesenchymal transition (EMT), or myofibroblast activation (MFA) on wound healing, the RNA abundance of gene products related to these pathways was measured by reverse transcription and quantitative polymerase chain reaction (RT-qPCR). Results : The epithelialization rate on Day 14 was significantly higher in the treatment group. The days that the epithelialization rate exceeded 85%, 90%, and 95% were significantly shorter in the treatment group. There was no significant difference in wound blood flow or RNA abundance related to TGFβ, EMT, or MFA-related pathways among the groups at any time point. Conclusion : The results demonstrate that the beta-blocker timolol accelerates epithelialization of mesh skin grafted full-thickness burn wounds through a mechanism other than improving wound blood flow.

Neurovascular unit, neuroinflammation and neurodegeneration markers in brain disorders

Neurovascular unit (NVU) inflammation via activation of glial cells and neuronal damage plays a critical role in neurodegenerative diseases. Though the exact mechanism of disease pathogenesis is not understood, certain biomarkers provide valuable insight into the disease pathogenesis, severity, progression and therapeutic efficacy. These markers can be used to assess pathophysiological status of brain cells including neurons, astrocytes, microglia, oligodendrocytes, specialized microvascular endothelial cells, pericytes, NVU, and blood-brain barrier (BBB) disruption. Damage or derangements in tight junction (TJ), adherens junction (AdJ), and gap junction (GJ) components of the BBB lead to increased permeability and neuroinflammation in various brain disorders including neurodegenerative disorders. Thus, neuroinflammatory markers can be evaluated in blood, cerebrospinal fluid (CSF), or brain tissues to determine neurological disease severity, progression, and therapeutic responsiveness. Chronic inflammation is common in age-related neurodegenerative disorders including Alzheimer’s disease (AD), Parkinson’s disease (PD), and dementia. Neurotrauma/traumatic brain injury (TBI) also leads to acute and chronic neuroinflammatory responses. The expression of some markers may also be altered many years or even decades before the onset of neurodegenerative disorders. In this review, we discuss markers of neuroinflammation, and neurodegeneration associated with acute and chronic brain disorders, especially those associated with neurovascular pathologies. These biomarkers can be evaluated in CSF, or brain tissues. Neurofilament light (NfL), ubiquitin C-terminal hydrolase-L1 (UCHL1), glial fibrillary acidic protein (GFAP), Ionized calcium-binding adaptor molecule 1 (Iba-1), transmembrane protein 119 (TMEM119), aquaporin, endothelin-1, and platelet-derived growth factor receptor beta (PDGFRβ) are some important neuroinflammatory markers. Recent BBB-on-a-chip modeling offers promising potential for providing an in-depth understanding of brain disorders and neurotherapeutics. Integration of these markers in clinical practice could potentially enhance early diagnosis, monitor disease progression, and improve therapeutic outcomes.

In vitro and computational investigation of antioxidant and anticancer properties of Streptomyces coeruleofuscus SCJ extract on MDA-MB-468 triple-negative breast cancer cells

This study aimed to explore the antioxidant potential of the ethyl acetate extract of Streptomyces coeruleofuscus SCJ strain, along with its inhibitory effects on the triple-negative human breast carcinoma cell line (MDA-MB-468). The ethyl acetate extract’s total phenolic and flavonoid contents were quantified, and its antioxidant activity was investigated using DPPH (1,1-Diphenyl-2-picrylhydrazyl), ABTS (2,2’-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), and FRAP (Ferric Reducing Antioxidant Power) assays. Furthermore, the cytotoxic effect of the organic extract from Streptomyces coeruleofuscus SCJ on MDA-MB-468 cancer cells was assessed via the crystal violet assay. In tandem, a thorough computational investigation was conducted to explore the pharmacokinetic properties of the identified components of the extract, utilizing the SwissADME and pKCSM web servers. Additionally, the molecular interactions between these components and Estrogen Receptor Beta, identified as a potential target, were probed through molecular docking studies. The results revealed that ethyl acetate extract of SCJ strain exhibited remarkable antioxidant activity, with 39.899 ± 1.56% and 35.798 ± 0.082% scavenging activities against DPPH and ABTS, respectively, at 1 mg/mL. The extract also displayed significant ferric reducing power, with a concentration of 1.087 ± 0.026 mg ascorbic acid equivalents per mg of dry extract. Furthermore, a strong positive correlation (p < 0.0001) between the antioxidant activity, the polyphenol and the flavonoid contents. Regarding anticancer activity, the SCJ strain extract demonstrated significant anticancer activity against TNBC MDA-MB-468 cancer cells, with an inhibition percentage of 62.76 ± 0.62%, 62.67 ± 0.93%, and 58.07 ± 4.82% at 25, 50, and 100 µg/mL of the extract, respectively. The HPLC-UV/vis analysis revealed nine phenolic compounds: gallic acid, sinapic acid, p-coumaric acid, cinnamic acid, trans-fereulic acid, syringic acid, chloroqenic acid, ellagic acid, epicatechin. Streptomyces coeruleofuscus SCJ showed promise for drug discovery, exhibiting antioxidant and anticancer effects.

Individual and combined effects of commercial glyphosate, atrazine and 2,4-D herbicides on the gerbil ventral prostate

Exposure to pesticides, individually or in a mixture, in drinking water is one of the main sources of human contamination, which causes adverse effects on the reproductive system. Our study aimed to investigate, the effects of a 90-day exposure to low concentrations of glyphosate (GLY), atrazine (ATZ), and 2,4-dichlorophenoxyacetic acid (2,4-D), in commercial formulations, on morphological, molecular, and hormonal parameters of the ventral prostate of gerbils (Meriones unguiculatus). The animals were exposed via drinking water to individual concentrations of GLY: 700 μg/L, ATZ: 3 μg/L, and 2,4-D: 70 μg/L, as well as to their mixture (MIX). Our findings showed an increase in prostatic complex relative weight in ATZ-exposed animals. Stereological and morphometric techniques indicated an increase in the percentage and thickness of muscular stroma, following an increase in the amount of collagen and reticular fibers in the MIX group. Histopathological analysis showed a decrease in the incidence of epithelial atrophy, subepithelial inflammation, and microacini in the MIX. On the other hand, ATZ-exposed animals showed an increase in hyperplasia and total prostatic intraepithelial neoplasia (PIN). The expression of caspase-3 decreased and estrogen receptor alpha (ERα) increased in the 2,4-D and MIX. Western blotting showed an increase in estrogen receptor beta (ERβ) expression in MIX-exposed animals. Testosterone levels decreased in animals from the GLY, ATZ and 2,4-D groups. Our findings provide evidence that individual or combined exposure to herbicides causes hormonal imbalance and morphological alterations, besides favoring the incidence of proliferative lesions in the prostate, predisposing the gland to more severe injuries.

The beta 2 adrenergic receptor cross-linked interactome identifies 14-3-3 proteins as regulating the availability of signaling-competent receptors.

The emerging picture of G protein-coupled receptor function suggests that the global signaling response is an integrated sum of a multitude of individual receptor responses, each regulated by their local protein environment. The beta 2 adrenergic receptor (B2AR) has long served as an example receptor in the development of this model. But the mechanism and the identity of the protein-protein interactions that govern the availability of receptors competent for signaling remains incompletely characterized. To address this question, we characterized the interactome of agonist-stimulated B2AR in HEK293 cells using FLAG co-immunoprecipitation coupled to SILAC labeling and mass spectrometry. Our B2AR cross-linked interactome identified 190 high-confidence proteins, including almost all known interacting proteins and six out of seven isoforms of the 14-3-3 family of scaffolding proteins. Inhibiting 14-3-3 proteins with the peptide difopein enhanced isoproterenol-stimulated adrenergic signaling via cAMP approximately three-fold, and increased both miniGs and arrestin recruitment to B2AR more than two fold each, without noticeably changing EC50 with respect to cAMP signaling or effector recruitment upon stimulation. Our results show that 14-3-3 proteins negatively regulate downstream signaling by inhibiting access of B2AR to effector proteins. We propose that 14-3-3 proteins maintain a dynamic pool of B2AR that has reduced signaling efficacy in response to acute agonist stimulation, limiting the amount of signaling-competent receptors at the plasma membrane. Significance Statement This study presents a new interactome of the agonist-stimulated beta 2 adrenergic receptor (B2AR), a paradigmatic GPCR that is both a model system for members of this class and an important signaling protein in respiratory, cardiovascular, and metabolic regulation. We identify 14-3-3 proteins as responsible for restricting B2AR access to signaling effectors and maintaining a receptor population that is insensitive to acute stimulation by agonists.

Sympathetic activity markers in patients with resistant hypertension with renal dysfunction

Aim. To study the informativeness of sympathetic activity markers and perirenal adipose tissue (PRAT) in assessing renal function decline in patients with resistant hypertension (RH).Material and methods. The study included 63 patients with RH of both sexes aged 40-80 years. The main group included 19 patients with chronic kidney disease (CKD). The control group consisted of 44 patients with RH without CKD. All patients were assessed for uric acid, blood lipid profile, beta-adrenergic reactivity of erythrocyte mem­branes, free metanephrine and normetanephrine in plasma and 24-hour urine. The renal function was assessed by the glomerular filtra­tion rate calculated using the CKD-EPI equation. Twenty-four hour blood pressure monitoring was performed on the brachial artery of one arm at intervals of 15 minutes during the day and 30 minutes at night. Kidney size and PRAT were calculated based on the magnetic reso­nance imaging.Results. In both groups of patients, a significant increase in blood normetanephrine and beta-adrenergic reactivity of erythrocyte mem­branes relative to the reference values was shown. Blood and 24-hour urine metanephrine were within the reference intervals. No differences were found between the sympathetic activity indices in the main and control groups. In the main group patients, the PRAT thickness was greater (p=0,013), and the kidney diameter was smaller (p=0,046) than in the control group patients.Conclusion. CKD in RH patients is not accompanied by additional significant changes in sympathetic regulation, assessed by the blood and 24-hour urine catecholamine levels, the degree of beta-adrenergic receptor desensitization and variability of blood pressure. PRAT increase according to magnetic resonance imaging in patients with RH is associated with a decrease in renal filtration function.

Interleukin-1 Beta rs16944 and rs1143634 and Interleukin-6 Receptor rs12083537 Single Nucleotide Polymorphisms as Potential Predictors of COVID-19 Severity.

Host genetic variation has been recognized as a key predictor of diverse clinical sequelae among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected patients. Insights into the link between the Interleukin-6 receptor (IL-6R) and Interleukin-1 beta (IL-1β) genetic variation and severe coronavirus disease 2019 (COVID-19) are crucial for developing new predictors and therapeutic targets. We aimed to investigate the association of IL-6R rs12083537, IL-1β rs16944, and IL-1β rs1143634 SNPs with the severity of COVID-19. Our study was conducted on 300 COVID-19-negative individuals (control group) and 299 COVID-19-positive cases, classified into mild, moderate, and severe subgroups. Analyses of IL-1β (rs16944, rs1143634) and IL-6R (rs12083537) SNPs' genotypes were performed using qPCR genotyping assays. The IL-1β (rs16944) CC genotype and IL-6R (rs12083537) GG genotype were substantially related to COVID-19 severity, which was also associated with comorbidities and some laboratory parameters (p < 0.001). The IL-1β (rs1143634) TT genotype was found to be protective. Likewise, the IL-1β (rs16944) CC genotype was associated with increased mortality. IL-1β rs16944 and IL-6R rs12083537 SNPs are promising potential predictors of SARS-CoV-2 disease severity. Meanwhile, the rs1143634 SNP T allele was protective against severity and mortality risk.

Suppressing PDGFRβ Signaling Enhances Myocyte Fusion to Promote Skeletal Muscle Regeneration.

Muscle cell fusion is critical for forming and maintaining multinucleated myotubes during skeletal muscle development and regeneration. However, the molecular mechanisms directing cell-cell fusion are not fully understood. Here, we identify platelet-derived growth factor receptor beta (PDGFRβ) signaling as a key modulator of myocyte fusion in adult muscle cells. Our findings demonstrate that genetic deletion of Pdgfrβ enhances muscle regeneration and increases myofiber size, whereas PDGFRβ activation impairs muscle repair. Inhibition of PDGFRβ activity promotes myonuclear accretion in both mouse and human myotubes, whereas PDGFRβ activation stalls myotube development by preventing cell spreading to limit fusion potential. Transcriptomics analysis show that PDGFRβ signaling cooperates with TGFβ signaling to direct myocyte size and fusion. Mechanistically, PDGFRβ signaling requires STAT1 activation, and blocking STAT1 phosphorylation enhances myofiber repair and size during regeneration. Collectively, PDGFRβ signaling acts as a regenerative checkpoint and represents a potential clinical target to rapidly boost skeletal muscle repair.

Structure of endothelin ETB receptor–Gi complex in a conformation stabilized by unique NPxxL motif

Endothelin type B receptor (ETBR) plays a crucial role in regulating blood pressure and humoral homeostasis, making it an important therapeutic target for related diseases. ETBR activation by the endogenous peptide hormones endothelin (ET)−1–3 stimulates several signaling pathways, including Gs, Gi/o, Gq/11, G12/13, and β-arrestin. Although the conserved NPxxY motif in transmembrane helix 7 (TM7) is important during GPCR activation, ETBR possesses the lesser known NPxxL motif. In this study, we present the cryo-EM structure of the ETBR–Gi complex, complemented by MD simulations and functional studies. These investigations reveal an unusual movement of TM7 to the intracellular side during ETBR activation and the essential roles of the diverse NPxxL motif in stabilizing the active conformation of ETBR and organizing the assembly of the binding pocket for the α5 helix of Gi protein. These findings enhance our understanding of the interactions between GPCRs and G proteins, thereby advancing the development of therapeutic strategies.