Effects Of Agonists Research Articles

Epac activation reduces trans-endothelial migration of undifferentiated neuroblastoma cells and cellular differentiation with a CDK inhibitor further enhances Epac effect.

Neuroblastoma (NB) is the most common solid extracranial neoplasm found in children and is derived from primitive sympathoadrenal neural precursor. The disease accounts for 15% of all cancer deaths in children. The mortality rate is high in patients presenting with a metastatic tumour even with extensive treatments. This signifies the need for further research towards the development of new additional therapies that can combat not only tumour growth but metastasis, especially amongst the high-risk groups. During metastasis, primary tumour cells become migratory and travel towards a capillary within the tumour. They then degrade the matrix surrounding the pericytes and endothelial cells traversing the endothelial barrier twice to establish a secondary. This led to the hypothesis that modulation of the endothelial cell junctional stability could have an influence on tumour metastasis. To test this hypothesis, agents that modulate endothelial permeability on NB cell line migration and invasion were assessed in vitro in a tissue culture model. The cAMP agonist and its antagonists were found to have no obvious effect on both SK-N-BE2C and SK-N-AS migration, invasion and proliferation. Next, NB cells were cocultured with HDMEC cells and live cell imaging was used to assess the effect of an Epac agonist on trans-endothelial cell migration of NB cells. Epac1 agonist remarkably reduced the trans-endothelial migration of both SK-N-BE2C and SK-N-AS cells. These results demonstrate that an Epac1 agonist may perhaps serve as an adjuvant to currently existing therapies for the high-risk NB patients.

Effect of GLP-1 receptor agonists on prostate cancer risk reduction: a systematic review and meta-analysis.

Prostate cancer is one of the most prevalent malignancies among men globally. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs), primarily used for type 2 diabetes mellitus (T2DM) management, have been investigated for their potential effects on cancer risks. This systematic review and meta-analysis aimed to assess the association between GLP-1 RA use and risk reduction of prostate cancer. A comprehensive literature search was conducted across PubMed, Embase, and Web of Science up to July 30, 2024. Studies that met the inclusion criteria randomized controlled trials, cohort studies, case-control studies, and observational studies assessing the incidence of prostate cancer in GLP-1 RA-treated patients were included. The quality of studies was evaluated using the Newcastle-Ottawa Scale and the Cochrane Risk of Bias tool. Meta-analysis was performed using a random effects model. A total of five studies were included, analyzing data from diverse international contexts. The included studies showed a reduced risk of prostate cancer with both adjusted and unadjusted effect estimates with GLP-1 RAs. The meta-analysis revealed an RR of 0.72 (95% CI: 0.610 to 0.832), indicating a statistically significant 28% reduction in prostate cancer risk associated with GLP-1 RA use compared to placebo or other antidiabetic drugs. Moderate heterogeneity was observed (I2 = 51%). Sensitivity analysis confirmed the results. The findings suggest a significant protective association between GLP-1 RA use and reduced prostate cancer risk in men, particularly those with T2DM. This supports the potential of GLP-1 RAs not only in diabetes management but also as a strategy to mitigate cancer risk. Further research is required to confirm these findings and explore the underlying mechanisms, considering different dosages, durations of therapy, and patient subgroups based on demographic and metabolic characteristics.

Activation of α7 nicotinic acetylcholine receptor augments nerve growth factor action on PCtrk cells

Although cigarette smoking is known to be a critical risk factor for various organ systems and cancers, accumulating evidence indicates that nicotine – a main constituent of cigarette smoking – can exert neuroprotective effects on neuronal cells through nicotinic acetylcholine receptors (nAChRs). However, the precise molecular mechanisms for nicotinic neuroprotective actions remain to be fully elucidated. In this study, we examine the effects of agonists, such as nicotine and PNU282987, on tropomyosin-related kinase (Trk)-dependent neuroprotective pathways in PC12 cells overexpressing a Trk neurotrophin receptor (PCtrk cells). We found that even considerably higher concentrations (mM range for nicotine and µM range for PN282987) of nAChR agonists exert favorable effects, such as the augmentation of nerve growth factor (NGF)-induced Trk neurotrophin receptor autophosphorylation of tyrosine residues and NGF-induced neurite extension. Moreover, nicotine upregulated reactive oxygen species (ROS) levels in the cells. ROS production was completely cancelled by pretreatment with Mito-Tempo, a mitochondria-targeted antioxidant, indicating that the main source of ROS production by nicotine was mitochondria. Furthermore, treatment with nAChR agonists appeared to induce autophagic flux, as evidenced by the upregulation of LC3-II expression in cells. Furthermore, sucrose density ultracentrifugation of nicotine-treated cells clearly disclosed the augmented recruitment of α7nAChR protein into the lipid rafts fraction of the membrane. Intriguingly, a pull-down assay of anti-Trk antibody immunoprecipitates clearly included α7nAChR protein, indicating that Trk and α7nAChR proteins form a complex. These results reveal a new molecular interaction between activated α7nAChR and Trk protein that may serve as a new molecular basis of nicotine-induced neuroprotective action.

Divergent modulation of activated protein C pleiotropic functions by antibodies that differ by a single amino acid

AbstractActivated protein C (APC) is a pleiotropic plasma protease with diverse functions derived from its anticoagulant, anti-inflammatory, and cytoprotective activities. The selective uncoupling and/or modulation of these APC activities by antibodies may have therapeutic benefit in diseases such as traumatic bleeding, hemophilia, sepsis, and ischemia. TPP-26870 is an antibody that targets a nonactive site of APC for the selective modulation of APC activities. To optimize the potency of TPP-26870, variants with single amino acid mutation in the complementarity-determining regions (CDRs) were screened, and 21 variants with improved KD were identified. Interestingly, the affinity maturation of TPP-26870 did not merely generate a panel of variants with higher potency in functional assays. Functional data demonstrated that the pleiotropic functions of APC were very sensitive to epitope-CDR interactions. Single amino acid mutations within the CDRs of TPP-26870 were sufficient to elicit divergent antagonistic and agonistic effects on the various APC functional activities. These include prolonged in vitro APC plasma half-life, increased inhibition of anticoagulant activity, and agonistic enhancement of histone H3 cleavage, while having less impact on protease-activated receptor 1 cleavage, compared with TPP-26870. This study illustrates that APC is highly sensitive to non–active site targeting that can lead to unpredictable changes in its activity profile of this pleiotropic enzyme. Furthermore, this study demonstrates the ability to modify APC functions to advance the potential development of APC-targeted antibodies as therapeutics for the treatment of diseases including trauma bleeding, hemophilia, ischemia, and sepsis.

Effect of GLP-1 receptor agonists on weight and cardiovascular outcomes: A review.

Diet and lifestyle modifications remain the foundation of obesity treatment, but they have historically proven insufficient for significant, long-term weight loss. As a result, there is a high demand for new pharmacologic treatments to promote weight loss and prevent life-threatening diseases associated with obesity. Researchers are particularly interested in 1 type of drug, glucagon-like peptide 1 receptor agonists (GLP-1 RAs), because of its promising potential in addressing the limitations of non-pharmacologic treatments. In addition to their role in weight loss, these drugs have shown promising early evidence of cardiovascular benefits in obese patients, further enhancing their clinical relevance. Semaglutide and liraglutide, which were initially approved for the treatment of type 2 diabetes, have since been approved by the Food and Drug Administration as weight loss medications due to their effectiveness in promoting significant and sustained weight loss. In this narrative review, we will explore the mechanism of GLP-1 RAs, their effects on weight loss, cardiovascular risk factors and outcomes, common adverse effects, and strategies for managing these effects.

CB1 Receptor Activation Provides Neuroprotection in an Animal Model of Glutamate-Induced Excitotoxicity Through a Reduction of NOX-2 Activity and Oxidative Stress.

Excitotoxicity is a process in which NADPH oxidase-2 (NOX-2) plays a pivotal role in the generation of reactive oxygen species (ROS). Oxidative stress influences the expression of Aquaporin 4 (AQP4), a water channel implicated in blood-brain barrier (BBB) permeability and edema formation. The endocannabinoid system is widely distributed in the brain, particularly through the cannabinoid receptor type 1 (CB1) and type 2 (CB2), which have been shown to have a neuroprotective function in brain injury. Given the significant involvement of NOX-2 in ROS production during excitotoxicity, our research aims to assess the participation of NOX-2 in the neuroprotective effect of the cannabinoid receptor agonist WIN55,212-2 against glutamate-induced excitotoxicity damage in the striatum using invivo model. Wild-type mice (C57BL/6) and NOX-2 KO (gp91Cybbtm1Din/J) were stereotactically injected in the striatum with monosodium glutamate or vehicle. Subsequently, a group of mice was administered an intraperitoneal dose of WIN55,212-2, AM251, or AM251/WIN55,212-2 following the intracerebral injection. Motor activity was assessed, and the lesion was examined through histological sections stained with cresyl violet. Additionally, brain water content and Evans blue assay were conducted. The activity of NOX was quantified, and the protein expression of CB1, gp91phox, AQP4, Iba-1, TNF-α, and NF-κB was analyzed using Western blot. Furthermore, ROS formation was measured through the DHE assay. The activation of the endocannabinoid receptors demonstrated a neuroprotective response during excitotoxicity, meditated by NOX-2. The reduction in ROS production led to a decrease in neuroinflammation, and AQP4 expression, resulting in reduced edema formation, and BBB permeability. During excitotoxic damage, WIN55,212-2 inhibits NOX-2-induced ROS production, reducing brain injury.

Protocol for a randomised, double-blinded, controlled trial of youth with childhood-onset obesity treated with semaglutide 2.4 mg/week: the RESETTLE trial

IntroductionChildhood-onset obesity poses significant health risks, including early-onset type 2 diabetes, cardiovascular disease, and reduced quality of life. Hospital-based non-pharmacological obesity care can reduce childhood obesity, but 25% of children do not respond. Therefore, this study investigates the effect of the glucagon-like peptide-1 receptor agonist, semaglutide, as an add-on to hospital-based obesity care in youth who still have obesity following hospital-based obesity care as children. Furthermore, biomedical and psychosocial factors linked to treatment response will be investigated, alongside an exercise-based strategy to prevent weight regain and maintain a healthy body composition after semaglutide treatment.Methods and analysisThis is an investigator-initiated, randomised, placebo-controlled, double-blind trial. We will enrol expectedly 180–270 young adults aged 18–28 years based on their previous response to a paediatric obesity management programme and their current body mass index (BMI). Participants are categorised into four groups: low treatment response (BMI SD score (SDS) reduction <0.10; BMI ≥30 kg/m2); medium treatment response (BMI SDS reduction >0.25; BMI ≥30 kg/m2); high treatment response (BMI SDS reduction >0.50; BMI <30 kg/m2) and a population-based reference group with normal weight development in childhood. Participants with BMI ≥30 kg/m2are randomised 2:1 to subcutaneous injections of semaglutide 2.4 mg/week or placebo as an add-on to hospital-based obesity care for 68 weeks. The primary outcome is the change in BMI from randomisation to the end of treatment with semaglutide compared with placebo. Secondary endpoints are changes in weight and body composition.Ethics and disseminationThe trial has been approved by the Danish Medicines Agency and the Ethical Committee of the Capital Region of Denmark (H-20039422). The trial will be conducted in accordance with the Declaration of Helsinki and follow the guidelines for Good Clinical Practice. Results will be presented at international scientific conferences and published in peer-reviewed scientific journals.Trial registration numberEudraCT 2019-002274-31.

Modulation of the K/BxN arthritis mouse model and the effector functions of human fibroblast-like synoviocytes by liver X receptors.

The role of liver X receptors (LXR) in rheumatoid arthritis (RA) remains controversial. We studied the effect of LXR agonists on fibroblast-like synoviocytes (FLS) from RA patients and the K/BxN arthritis model in LXRα and β double-deficient (Nr1h2/3-/-) mice. Two synthetic LXR agonists, GW3965 and T0901317, were used to activate LXRs and investigate their effects on cell growth, proliferation and matrix metalloproteinases, and chemokine production in cultured FLS from RA patients. The murine model K/BxN serum transfer of inflammatory arthritis in Nr1h2/3-/- animals was used to investigate the role of LXRs on joint inflammation in vivo. LXR agonists inhibited the FLS proliferative capacity in response to TNF, the chemokine-induced migration, the collagenase activity in FLS supernatant and FLS CXCL12 production. In the K/BxN mouse model, Nr1h2/3-/- animals showed aggravated arthritis, histological inflammation, and joint destruction, as well as an increase in synovial metalloproteases and expression of proinflammatory mediators such as IL-1β and CCL2 in joints compared with wild type animals. Taken together, these data underscore the importance of LXRs in modulating the joint inflammatory response and highlight them as potential therapeutic targets in RA.

Glucagon-like Peptide-1 Receptor Agonist Use is Associated With Increased Risk of Perioperative Complication and Readmission Following Shoulder Arthroplasty

Glucagon-like peptide-1 (GLP-1) receptor agonists, increasingly used for diabetes management and weight loss, have been linked to lower readmission rates after knee and hip arthroplasty. However, their impact on total shoulder arthroplasty (TSA) outcomes remains unclear. This study investigates the effects of GLP-1 receptor agonists on major complications and revisions following TSA. A retrospective query of the TriNetX database from 2010 to 2023 was performed to identify patients who underwent anatomic or reverse TSA and were prescribed GLP-1 receptor agonists. GLP-1 receptor agonist users were 1:1 propensity score-matched to controls for demographic factors and comorbidities, yielding 1,259 patients in each group. Outcomes included 90-day postoperative medical complications and readmission and revision surgery at 2 years. Odds ratios (ORs), 95% confidence intervals, and P values were calculated. After Bonferroni correction, P < 0.005 was considered significant. GLP-1 receptor agonist users (n = 1,259) experienced significantly higher rates of deep vein thrombosis (1.6% vs. 0.9%; OR 3.0; P = 0.001), myocardial infarction (1.60% vs. 0.9%; OR 2.84; P = 0.003), pneumonia (3.34% vs 1.50%; OR 2.25; P = 0.003), transfusion (7.1% vs. 4.3%; OR 1.7; P = 0.003), and readmission (8.1% vs 5.2%; OR 1.6; P = 0.004) in the 90-day postoperative period compared to patients not taking GLP-1 receptor agonists. There were no differences in the rates of stroke, pulmonary embolism, postoperative anemia, or renal failure. In patients with a minimum 2-year follow-up (n = 776), there was no difference in revision rate (3.2% vs 1.8%; OR 1.8; P = 0.07). GLP-1 receptor agonist use during TSA was associated with an increased risk of deep vein thrombosis, myocardial infarction, pneumonia, need for transfusion, and readmission. Further investigation into the perioperative risk assessment and medical optimization of patients utilizing GLP-1 receptor agonists may be warranted.

Neuroprotective effects of GLP-1 receptor agonists in neurodegenerative Disorders: A Large-Scale Propensity-Matched cohort study

BackgroundGLP-1 receptor agonists, traditionally used for treating type 2 diabetes mellitus and obesity, have demonstrated anti-inflammatory properties. However, their potential neuroprotective effects in neurodegenerative disorders remain unclear. ObjectiveTo evaluate the impact of GLP-1 receptor agonists on the risk of developing various neurodegenerative conditions in obese patients. MethodsThis comprehensive retrospective cohort study analyzed data from 5,307,845 obese adult patients across 73 healthcare organizations in 17 countries. Propensity score matching was performed, resulting in 102,935 patients in each cohort. We compared the risk of developing neurodegenerative disorders between obese patients receiving GLP-1 receptor agonist therapy and those who were not. ResultsObese patients treated with GLP-1 receptor agonists showed significantly lower risks of developing Alzheimer’s disease (RR = 0.627, 95 %CI = 0.481–0.817), Lewy body dementia (RR = 0.590, 95 %CI = 0.462–0.753), and vascular dementia (RR = 0.438, 95 %CI = 0.327–0.588). The risk reduction for Parkinson’s disease was not statistically significant overall (RR = 0.784, 95 %CI = 0.580–1.058) but was significant for semaglutide users (RR = 0.574, 95 %CI = 0.369–0.893). Semaglutide consistently showed the most pronounced protective effects across all disorders. Additionally, a significant reduction in all-cause mortality was observed (HR = 0.525, 95 %CI = 0.493–0.558). ConclusionThis study provides evidence that the effects of GLP-1 receptor agonists may extend beyond their known metabolic and cardioprotective benefits to include neuroprotection, associated with a decreased risk of developing various neurodegenerative disorders. These findings suggest the potential for expanding the therapeutic applications of GLP-1 receptor agonists to improve neurocognitive outcomes. Further research is warranted to elucidate the mechanisms underlying these neuroprotective effects and to explore their clinical applications in neurodegenerative disease prevention and treatment.

Effect of Alpha-2 Agonists on the Locomotor Activity in Adult Zebrafish

Effect of Alpha-2 Agonists on the Locomotor Activity in Adult Zebrafish

Once-Weekly Semaglutide in Persons with Obesity and Knee Osteoarthritis

BackgroundWeight reduction has been shown to alleviate symptoms of osteoarthritis of the knee, including pain. The effect of glucagon-like peptide-1 receptor agonists on outcomes in knee osteoarthritis among persons with obesity has not been well studied.MethodsWe conducted a 68-week, double-blind, randomized, placebo-controlled trial at 61 sites in 11 countries. Participants with obesity (a body-mass index [BMI; the weight in kilograms divided by the square of the height in meters] of ≥30) and a clinical and radiologic diagnosis of moderate knee osteoarthritis with at least moderate pain were randomly assigned, in a 2:1 ratio, to receive once-weekly subcutaneous semaglutide (2.4 mg) or placebo, in addition to counseling on physical activity and a reduced-calorie diet. The primary end points were the percentage change in body weight and the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score (on a scale of 0 to 100, with higher scores reflecting worse outcomes) from baseline to week 68. A key confirmatory secondary end point was the physical-function score on the 36-Item Short Form Health Survey (SF-36), version 2 (on a scale of 0 to 100, with higher scores indicating greater well-being).ResultsA total of 407 participants were enrolled. The mean age was 56 years, the mean BMI 40.3, and the mean WOMAC pain score 70.9. A total of 81.6% of the participants were women. The mean change in body weight from baseline to week 68 was −13.7% with semaglutide and −3.2% with placebo (P<0.001). The mean change in the WOMAC pain score at week 68 was −41.7 points with semaglutide and −27.5 points with placebo (P<0.001). Participants in the semaglutide group had a greater improvement in SF-36 physical-function score than those in the placebo group (mean change, 12.0 points vs. 6.5 points; P<0.001). The incidence of serious adverse events was similar in the two groups. Adverse events that led to permanent discontinuation of the trial regimen occurred in 6.7% of the participants in the semaglutide group and in 3.0% in the placebo group, with gastrointestinal disorders being the most common reason for discontinuation.ConclusionsAmong participants with obesity and knee osteoarthritis with moderate-to-severe pain, treatment with once-weekly injectable semaglutide resulted in significantly greater reductions in body weight and pain related to knee osteoarthritis than placebo. (Funded by Novo Nordisk; STEP 9 ClinicalTrials.gov number, NCT05064735.)

Impact of noradrenergic inhibition on neuroinflammation and pathophysiology in mouse models of Alzheimer's disease.

Norepinephrine (NE) modulates cognitive function, arousal, attention, and responses to novelty and stress, and also regulates neuroinflammation. We previously demonstrated behavioral and immunomodulatory effects of beta-adrenergic pharmacology in mouse models of Alzheimer's disease (AD). The current studies were designed to block noradrenergic signaling in 5XFAD mice through 1 ) chemogenetic inhibition of the locus coeruleus (LC), 2) pharmacologic blocking of β-adrenergic receptors, and 3) conditional deletion of β1- or β2-adrenergic receptors (adrb1 or adrb2) in microglia. First, brain-wide AD pathology was mapped in 3D by imaging immunolabeled, cleared 5XFAD brains to assess the overlap between Aβ pathology, reactive microglia, and the loss of tyrosine hydroxylase (TH) expression in the catecholaminergic system. To examine the effects of inhibiting the LC NE system in the 5XFAD model, inhibitory (Gi) DREADD receptors were expressed specifically in LC NE neurons. LC NE neurons were chronically inhibited through the subcutaneous pump administration of the DREADD agonist clozapine-N-oxide (CNO). Plasma and brains were collected for assessment of neuroinflammation and pathology. A separate cohort of 5XFAD mice was chronically dosed with the beta-adrenergic antagonist propranolol or vehicle and evaluated for behavior, as well as post-mortem neuroinflammation and pathology. Finally, we used 5XFAD mice with conditional deletion of either adrb1 or adrb2 in microglia to assess neuroinflammation and pathology mediated by β-adrenergic signaling. Using iDISCO, light sheet fluorescence microscopy, and novel analyses, we detected widespread microgliosis and amyloid pathology, along with modest TH downregulation in fibers across multiple brain regions, in contrast to the spatially limited TH downregulation observed in neurons. Both chemogenetic inhibition of LC adrenergic signaling and pharmacological inhibition of beta-adrenergic receptors potentiated neuroinflammation without altering amyloid beta pathology. Conditional deletion of adrb1 in microglia did not affect neuroinflammation. Conditional deletion of adrb2 in microglia attenuated inflammation and pathology in females but had no effect in males. Overall, these data support previous observations demonstrating the immunomodulatory effects of beta-adrenergic signaling in the pathophysiology of brain disorders and suggest that adrenergic receptors on cell types other than microglia, such as astrocytes, may predominantly mediate the disease-modifying effects of β-adrenergic agonists in the brain.

Effectiveness and Safety of GLP-1 Receptor Agonists in Patients with Type 1 Diabetes.

Background: GLP-1 receptor agonists (GLP-1RA) are used in the management of type II diabetes mellitus or obesity, although its role in patients with type I diabetes mellitus (T1DM) has been debated. This study aimed to investigate the efficacy and safety of GLP-1RA in patients with T1DM using real-world data. Methods: This multicenter, retrospective study was conducted at three tertiary medical centers in Riyadh, Saudi Arabia. The study followed up patients (>16 years old) with T1DM treated with insulin followed by GLP-1RA add-on therapy. The efficacy outcomes included changes in HbA1c, body weight, and insulin requirements from baseline to each follow-up visit. The main safety outcomes assessed included hypoglycemic events and gastrointestinal (GI) adverse events. Results: The study included 144 patients with a mean age of 33.0 ± 10.1 years. Semaglutide was the most used GLP-1RA (63.9%) followed by liraglutide (34.0%). From baseline to 3-month follow-up, HbA1c (mean difference (MD) = -0.8%; p = 0.0053), weight (MD = -2.4 kg; p = 0.0253), and daily basal insulin dose (MD = -2.1 units; p = 0.0349) were significantly reduced. Likewise, HbA1c (MD = -0.5%; p = 0.0004), weight (MD = -3.6 kg; p < 0.0001), and daily basal insulin (MD = -2.4 units; p = 0.0282) were significantly reduced at the 4-6-month follow-up. The significant reductions in HbA1c, weight, and daily basal insulin levels were consistent for up to 18-month follow-up. Only one patient had a major hypoglycemic event, whereas 8.3% of the patients had GI adverse events. Conclusions: Overall, significant improvements in glycemic control, weight loss, and insulin requirements were observed with the use of GLP-1RA in patients with T1DM, with a limited number of GI adverse events.

Effects of MDA-19 on Zebrafish Larval Behavior: Perspectives From Neurodevelopment, Oxidative Stress, and Metabolomics.

As global regulations on synthetic cannabinoids tighten, illicit vendors increasingly turn to new structures of synthetic cannabinoids to evade legal scrutiny. MDA-19, a novel synthetic cannabinoid, exhibited significant agonistic effects on type 2 cannabinoid receptors invivo and showed emerging trends of abuse in illicit markets. However, research on the toxicological effects of MDA-19 remains scarce. In this study, we examined the effects of MDA-19 on neurodevelopment, behavior, oxidative stress, and metabolomics by exposing zebrafish embryos to MDA-19 solutions with concentrations of 1, 10, and 20 mg/L over 5 days. Results revealed that exposure to 10 and 20 mg/L of MDA-19 accelerated hatching in zebrafish embryos but led to reduced body length without affecting mortality or malformation. Furthermore, exposure to all concentrations of MDA-19 resulted in diminished swimming ability and reduced activity time in zebrafish. Transgenic zebrafish (hb9-GFP) exposed to MDA-19 exhibited impaired development of spinal motor neurons. Notably, exposure to 20 mg/L MDA-19 increased the levels of reactive oxygen species (ROS) in zebrafish and elevated the activity of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT), while the levels of the lipid oxidation product malondialdehyde (MDA) remained unaffected. Nontargeted metabolomics analyses showed that MDA-19 interfered with multiple metabolic pathways affecting energy metabolism, such as alanine, aspartate, and glutamate metabolism; the citric acid cycle (TCA cycle), pantothenate, and coenzyme A biosynthesis; and purine metabolism. In conclusion, the present study provided the essential evidence for the neurotoxic effects of MDA-19, which was associated with impaired neurodevelopment, dysregulation of oxidative stress homeostasis, and altered energy metabolism.

A newly developed small-molecule ErbB4 agonist reduces reactive cardiac fibrosis and adverse ventricular remodelling after myocardial infarction in a sex-specific manner

Abstract Background The beneficial effects of the neuregulin/ErbB pathway on the diseased heart have been well-established. The anti-fibrotic and cardioprotective aspects of neuregulin are largely attributable to the activation of the ErbB4 receptor. We recently developed a small-molecule selective ErbB4 agonist, which reduced collagen production in cultured fibroblasts and prevented oxidative-stress induced cardiomyocyte death in vitro. Purpose In order to evaluate the in vivo effects of this small-molecule ErbB4 agonist (referred to as compound, Cpd), we assessed its effect on left ventricular remodelling, cardiac fibrosis and cardiac function in a murine model of myocardial infarction (MI). Since there is a potential interaction between ErbB4 and the oestrogen receptor, we also aimed to evaluate whether these effects were sex-dependent. We hypothesised that Cpd would attenuate left ventricular remodelling, reduce cardiac fibrosis and help retain cardiac function in a sex-specific manner. Methods Mice were divided by sex and then further divided into three experimental groups: a sham group, an MI group receiving Cpd (MI/Cpd), and a control MI group receiving vehicle only (MI/Veh). MI was induced by ligating the left descending coronary artery. Seven days after MI, mice started treatment with either Cpd (2mg/kg/d) or its vehicle through subcutaneous osmotic minipumps. Cardiac ultrasound was performed weekly until mice were sacrificed after four weeks of treatment. Hearts were excised and stained with Masson’s trichrome to assess reactive cardiac fibrosis in the myocardium of the left ventricle, located remote from the infarction scar. A WGA-isolectinB4-DAPI immunofluorescent stain was performed to assess cardiomyocyte cross-sectional area in order to evaluate cardiomyocyte hypertrophy. Results In females (n=25), Cpd significantly decreased left ventricular end-diastolic volume compared to vehicle (LVEDV, Fig.1A, 80±23 µl vs.108±29 µl, p=0.045) and induced a slightly increased left ventricular ejection fraction (LVEF, Fig.1B, 32±12% vs. 22±9%, p=0.086). In addition, Cpd significantly reduced reactive interstitial fibrosis myocardium (Fig.1C, fibrotic area, 1.4±1.0% vs. vehicle: 3.8±3.1%, p=0.0363). In males (n=30), Cpd had no significant effects on either of the parameters mentioned above, (Fig.1E-G). There was no significant treatment effect in either group on cardiomyocyte cross sectional area (Fig.1D, Fig.1H). Conclusion Treatment with the novel small-molecule ErbB4 agonist attenuates left ventricular dilation and reactive interstitial fibrosis after MI in female mice, but not in males. These data support the premise that small molecule-induced ErbB4 activation is a potential new therapy for heart failure, especially in female patients. The mechanisms underlying the sex-dependent effects warrant further exploration.Figure 1

CS585, a novel prostacyclin receptor agonist, demonstrates sustained efficacy in vivo in the prevention of thrombosis

Abstract Background Uncontrolled platelet activity resulting from cardiovascular disease can lead to occlusive thrombi, culminating in myocardial infarction or stroke. Despite major advances in anti-platelet therapeutics, many patients remain at risk. Although prostacyclin (IP) receptor agonists are currently used for the treatment of pulmonary arterial hypertension (PAH), activation of the IP receptor has been shown to decrease platelet reactivity. However, engaging the IP receptor as a therapeutic target was previously considered unviable due to the lack of a sustained effect of current IP agonists in the blood. The development of an IP agonist with sustained effects in the blood would represent a novel prevention strategy in targeting platelet hyperreactivity and thrombosis. Purpose Assess the stability profile of CS585, an IV and orally bioavailable IP agonist, compared to FDA-approved IP agonists iloprost and selexipag, with regards to sustained activity in vivo in the blood in limiting platelet activation and thrombosis. Methods Using ex vivo and in vivo mouse models, we assessed the timeframe of effect of CS585, iloprost and selexipag in blood. Blood was drawn from wild-type mice 24 hours following a single IV dose of CS585, iloprost or selexipag. Platelet adhesion and blood clotting were measured using perfusion flow chamber at arterial shear and total thrombus activation system (T-TAS), respectively. In vivo, platelets and fibrin were labelled 24 hours post IV or oral administration of CS585, iloprost or selexipag, and accumulation at the site of injury was measured using the cremaster arteriole injury thrombosis assay. Results Blood drawn from mice administered CS585 was observed to show a decrease in platelet adhesion and clot formation in the perfusion flow chamber and T-TAS assays. The effects of iloprost and selexipag are no longer observed at 24 hours post-administration. Administration of CS585 resulted in sustained inhibition of platelet accumulation and fibrin formation in the laser-induced cremaster arteriole thrombosis assay up to 18 hours post-administration. In mice administered iloprost, a decrease in thrombus formation was observed 10 minutes post-administration, but thrombus size returned to vehicle levels by 4 hours. Selexipag-dosed mice demonstrated inhibition of thrombus formation up to 4 hours, but effects were no longer observed at 18 hours. Conclusions CS585, a novel IP agonist, inhibits platelet activation and clot formation up to 24 hours post-administration. In both in vivo and ex vivo models, we demonstrate the sustained effects of CS585. In contrast, current FDA-approved IP agonists do not possess an effect profile sufficient to target the IP receptor in blood. By overcoming the sustainability challenge facing IP agonists, CS585 represents a novel approach to anti-platelet treatment of thrombotic diseases, which could include thrombosis, VTE, secondary prevention after MI and stroke, and PAH.

Effect of glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter-2 inhibitors and their combination on carotid intima-media thickness

Abstract Background/Introduction Type 2 diabetes mellitus (T2DM) is an additional factor for exacerbation of atherosclerosis increasing the risk for ischemic attacks such as coronary artery disease and ischemic stroke. Evaluation of carotid artery atherosclerosis through ultrasound techniques is a useful tool for risk stratification in type 2 diabetic patients. Purpose We investigated the effects of insulin, glucagon like peptide-1 receptor agonists (GLP-1RA), sodium-glucose cotransporter-2 inhibitors (SGLT-2i) and their combination on carotid intima-media thickness (cIMT) of T2DM patients. Methods A total of 320 T2DM patients were randomized to receive insulin (n = 80), liraglutide (n = 80), empagliflozin (n = 80) or their combination (GLP-1RA+SGLT-2i) (n = 80) as add-on to metformin. At baseline, at 6 and at 12 months of treatment, we measured the maximal thickness of six major points including right and left common carotid, carotid bifurcation and internal carotids. Finally, we calculated the average cIMT of all six segments (three on each side) to get mean cIMT. Results Compared to baseline, all patients had significantly reduced cIMT at 6 and at 12 months of treatment (p &amp;lt; 0.001; Table). A significant interaction of follow-up time with the type of treatment was observed regarding cIMT levels (F = 7.203, p for interaction &amp;lt; 0.001) in a model including age, sex, smoking, baseline body mass index, glucose levels, glycosylated hemoglobin, levels of blood lipids and their changes at 6 and 12 months of treatment as covariates. At 6 months, patients who were treated with GLP-1RA, SGLT-2i and those under the combination GLP-1RA+SGLT-2i showed a greater reduction of cIMT (-2.5%, -2.4% and -5.8%) compared to insulin (-0.8%; p = 0.008, p = 0.022, and p &amp;lt; 0.001, respectively). Moreover, at 12 months patients under GLP-1RA, SGLT-2i and their combination achieved remarkable reduction of cIMT (-7.4%, -4.9% and -10%) than those under insulin (-1.7%, p &amp;lt; 0.001 for all comparisons). Conclusions Twelve-month treatment with GLP-1RA, SGLT-2i and their combination resulted in reduction of cIMT in T2DM. The combined treatment was superior and additive to each regimen separately.Table

Effects of glucagon-like peptide-1 receptor agonists, sodium-glucose cotransporter-2 inhibitors and their combination on mitochondrial-derived peptide-c and on markers of neurohumoral activation

Abstract Background/Introduction Type-2 diabetes mellitus (T2DM) is associated with increased prevalence of cardiovascular disease. Purpose We investigated the effects of insulin, glucagon like peptide-1 receptor agonists (GLP-1RA), sodium-glucose cotransporter-2 inhibitors (SGLT-2i) and their combination on mitochondrial-derived peptide-c (MOTS-c), N-terminal pro B-type natriuretic peptide (NT-proBNP), growth differentiation factor (GDF)-15, oxidant and antioxidant biomarkers and cardiovascular function of T2DM patients. Methods A total of 160 T2DM patients were randomized to insulin (n = 40), liraglutide (n = 40), empagliflozin (n = 40) or their combination (GLP-1RA+SGLT-2i) (n = 40) as add-on to metformin. We measured at baseline, at 4 and at 12 months of treatment: a) plasma levels of MOTS-c, NT-proBNP and GDF-15, b) thiobarbituric acid reactive substances (TBARS), as an oxidant biomarkers, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), as an antioxidant biomarker, and c) global left ventricular longitudinal strain (GLS) and global work index (GWI) using speckle-tracking imaging. Results Twelve months after treatment, treatment with SGLT-2i and GLP-1RA+SGLT-2i improved MOTS-c (14.89 ± 11.27 vs. 7.26 ± 4.21 ng/mL, p=0.009, 6.49 ± 3.91 vs. 5.6 ± 3.38 ng/mL, p=0.029, respectively), while treatment with insulin and GLP-1RA had a neutral effect on this biomarker (p &amp;gt; 0.05; Table). GLP-1RA, SGLT-2i and their combination showed a greater reduction of NT-proBNP (-43.1% vs. -54.2% vs. -56.9% vs. -14.7%; Figure) and GDF-15 (-14.8% vs. -15.2% vs. -16.1% vs. -0.9%) than insulin (p &amp;lt; 0.05 for all comparisons), despite the fact that all patient achieved adequate glycemic control. GLP-1RA or GLP-1RA+SGLT-2i provided a remarkable reduction of TBARS and increase of GLS and GWI compared to insulin or SGLT-2i (p &amp;lt; 0.05). In all patients, at 4 and at 12 months, the percentage reduction of NT-proBNP was associated with the improvement of TBARS, GLS and GWI (p &amp;lt; 0.05). The percentage reduction of GDF-15 was correlated with the increase of ABTS and with the improvement of GLS at 4 and 12 months (p &amp;lt; 0.05). In SGLT-2i group, the percentage increase of MOTS-c was related with the percentage reduction of GDF-15 (r = 0.81, p = 0.005) at 12 months. Conclusions Twelve-month treatment with GLP-1RA, SGLT-2i and their combination resulted in reduction of cardiac biomarkers in parallel with a greater decrease of oxidative stress than insulin in T2DM. SGLT-2i appears more effective in the improvement of MOTS-c and markers of neurohumoral activation.TableFigure

Effects of sodium-glucose contrasporter-2 inhibitors and glucagon-like peptide-1 receptor agonists on arterial stiffness, coronary flow reserve and liver steatosis in diabetes

Abstract Background Patients with type 2 diabetes mellitus (T2DM) and nonalcoholic fatty liver disease (NAFLD) present an increased risk of cardiovascular disease. Sodium-glucose contrasporter-2 inhibitors (SGLT-2i) and glucagon-like peptide-1 receptor agonists (GLP-1RA) have been shown to significantly decrease the risk of cardiovascular complications. Purpose The aim of the study was to investigate the effect of treatment with SGLT-2i or GLP-1RA on cardiovascular function and liver steatosis and fibrosis in patients with T2DM and NAFLD. Methods Forty patients with T2DM and NAFLD (mean age: 58 ± 11 years) were randomized to receive SGLT-2i (dapagliflozin; n = 20) or GLP-1RA (dulaglutide; n = 20). At baseline and after 6 and 12 months of treatment, we measured: (1) perfused boundary region (PBR) of the sublingual microvessels with a diameter 5-25μm using Sidestream Dark Field camera (Microscan, Glycocheck). Increased PBR indicates reduced glycocalyx thickness. (2) Pulse wave velocity (PWV) using Complior (ALAM Medical), (3) coronary flow reserve (CFR) using Doppler echocardiography, (4) LV global longitudinal strain (GLS) using speckle-tracking echocardiography, (5) controlled attenuation parameter (CAP) score to assess steatosis grade and liver stiffness (E) to evaluate fibrosis score using liver elastography (FibroScan, Echosens), and (6) NAFLD fibrosis score (NFS). Results At baseline, patients between the two groups had similar age, sex, HbA1c, steatosis grade, fibrosis score and markers of cardiovascular function (p &amp;gt; 0.05). Compared with baseline, all patients had reduced PBR, PWV, CAP, E and NFS and increased CFR and GLS (p &amp;lt; 0.01) after 12-month treatment. In the whole study population, the percentage reduction of CAP and NFS was correlated with the corresponding decrease of PBR (r = 0.248 and r = 0.387), PWV (r = 0.290 and r = 0.281) and with the increase of GLS (r = -0.320 and r = -0.295) after 12-month treatment (p &amp;lt; 0.05 for all correlations). Both treatments with SGLT-2i and GLP-1RA reduced markers of liver steatosis and fibrosis (Table). Conclusion Both treatments with SGLT-2i and GLP-1RA improve cardiovascular function and reduce liver steatosis in patients with T2DM and NAFLD after 12 months.