Suppression of angiotensin II-activated NOX4/NADPH oxidase and mitochondrial dysfunction by preserving glucagon-like peptide-1 attenuates myocardial fibrosis and hypertension

NADPH Oxidases in Neurodegenerative Disorders: Mechanisms and Therapeutic Opportunities

Significance: The nicotinamide adenine dinucleotide phosphate oxidase (NOX) enzyme family, located in the central nervous system, is recognized as a source of reactive oxygen species (ROS) in the brain. Despite its importance in cellular processes, excessive ROS generation leads to cell death and is involved in the pathogenesis of neurodegenerative disorders. Recent advances: NOX enzymes contribute to the development of neurodegenerative diseases, such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and stroke, highlighting their potential as targets for future therapeutic development. This review will discuss NOX's contribution and therapeutic targeting potential in neurodegenerative diseases, focusing on PD, AD, ALS, and stroke. Critical issues: Homeostatic and physiological levels of ROS are crucial for regulating several processes, such as development, memory, neuronal signaling, and vascular homeostasis. However, NOX-mediated excessive ROS generation is deeply involved in the damage of DNA, proteins, and lipids, leading to cell death in the pathogenesis of a wide range of diseases, namely neurodegenerative diseases. Future directions: It is essential to understand the role of NOX homologs in neurodegenerative disorders and the pathological mechanisms undergoing neurodegeneration mediated by increased levels of ROS. This further knowledge will allow the development of new specific NOX inhibitors and their application for neurodegenerative disease therapeutics.

Unraveling the Cardiac Matrix: From Diabetes to Heart Failure, Exploring Pathways and Potential Medications

Myocardial infarction (MI) often leads to heart failure (HF) through acute or chronic maladaptive remodeling processes. This establishes coronary artery disease (CAD) and HF as significant contributors to cardiovascular illness and death. Therefore, treatment strategies for patients with CAD primarily focus on preventing MI and lessening the impact of HF after an MI event. Myocardial fibrosis, characterized by abnormal extracellular matrix (ECM) deposition, is central to cardiac remodeling. Understanding these processes is key to identifying new treatment targets. Recent studies highlight SGLT2 inhibitors (SGLT2i) and GLP-1 receptor agonists (GLP1-RAs) as favorable options in managing type 2 diabetes due to their low hypoglycemic risk and cardiovascular benefits. This review explores inflammation's role in cardiac fibrosis and evaluates emerging anti-diabetic medications' effectiveness, such as SGLT2i, GLP1-RAs, and dipeptidyl peptidase-4 inhibitors (DPP4i), in preventing fibrosis in patients with diabetes post-acute MI. Recent studies were analyzed to identify effective medications in reducing fibrosis risk in these patients. By addressing these areas, we can advance our understanding of the potential benefits of anti-diabetic medications in reducing cardiac fibrosis post-MI and improve patient outcomes in individuals with diabetes at risk of HF.

Linagliptin ameliorates tacrolimus-induced renal injury: role of Nrf2/HO-1 and HIF-1α/CTGF/PAI-1

BACKGROUND

Tacrolimus (TAC) is a frequently used immunosuppressive medication in organ transplantation. However, its nephrotoxic impact limits its long-term usage. This study aims to investigate the effect of linagliptin (Lina) on TAC-induced renal injury and its underlying mechanisms.

METHODS AND RESULTS

Thirty-two Sprague Dawley rats were treated with TAC (1.5 mg/kg/day, subcutaneously) and/or Lina (5 mg/kg/day, orally) for 4 weeks. Histological examination was conducted, and serum and urinary biomarkers were measured to assess kidney function and integrity. Furthermore, ELISA, Western blot analysis and immunohistochemical assay were employed to determine signaling molecules of oxidative stress, profibrogenic, hypoxic, and apoptotic proteins. Tacrolimus caused renal dysfunction and histological deterioration evidenced by increased serum creatinine, blood urea nitrogen (BUN), urinary cystatin C, and decreased serum albumin as well as elevated tubular injury and interstitial fibrosis scores. Additionally, TAC significantly increased the expression of collagen type-1, alpha-smooth muscle actin (α-SMA), plasminogen activator inhibitor-1 (PAI-1), and transforming growth factor-beta1 (TGF-β1) renal content. Moreover, TAC decreased the expression of nuclear factor erythroid-2-related factor2 (Nrf2), heme oxygenase 1 (HO-1), and mitochondrial superoxide dismutase (SOD2). In addition, TAC increased protein expression of hypoxia-inducible factor1-alpha (HIF-1α), connective tissue growth factor (CTGF), inducible nitric oxide synthase (iNOS), 8-hydroxy-2-deoxyguanosine (8-OHdG), as well as nitric oxide (NO), 4-hydroxynonenal, caspase-3 and Bax renal contents. Furthermore, TAC decreased Bcl-2 renal contents. The Lina administration markedly attenuated these alterations.

CONCLUSION

Lina ameliorated TAC-induced kidney injury through modulation of oxidative stress, hypoxia, and apoptosis related proteins.

GLP-1 receptor agonists and myocardial metabolism in atrial fibrillation

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Many medical conditions, including hypertension, diabetes, obesity, sleep apnea, and heart failure (HF), increase the risk for AF. Cardiomyocytes have unique metabolic characteristics to maintain adenosine triphosphate production. Significant changes occur in myocardial metabolism in AF. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been used to control blood glucose fluctuations and weight in the treatment of type 2 diabetes mellitus (T2DM) and obesity. GLP-1RAs have also been shown to reduce oxidative stress, inflammation, autonomic nervous system modulation, and mitochondrial function. This article reviews the changes in metabolic characteristics in cardiomyocytes in AF. Although the clinical trial outcomes are unsatisfactory, the findings demonstrate that GLP-1 RAs can improve myocardial metabolism in the presence of various risk factors, lowering the incidence of AF.

The value of low-intensity pulsed ultrasound in reducing ovarian injury caused by chemotherapy in mice

BACKGROUND

Ovarian damage and follicle loss are major side effects of chemotherapy in young female patients with cancer. However, effective strategies to prevent these injuries are still lacking. The purpose of this study was to verify low-intensity pulsed ultrasound (LIPUS) can reduce ovarian injury caused by chemotherapy and to explore its underlying mechanisms in mice model.

METHODS

The mice were randomly divided into the Control group, Cisplatin group, and Cisplatin + LIPUS group. The Cisplatin group and Cisplatin + LIPUS group were intraperitoneally injected with cisplatin every other day for a total of 10 injections, and the Control group was injected with saline. On the second day of each injection, the Cisplatin + LIPUS group received irradiation, whereas the other two groups received sham irradiation. We used a variety of biotechnologies to detect the differences in follicle count, granulosa cell apoptosis, fibrosis, transcriptome level, oxidative damage, and inflammation in differently treated mice.

RESULT

LIPUS was able to reduce primordial follicle pool depletion induced by cisplatin and inhibit the apoptosis of granulosa cells. Transcriptomic results confirmed that LIPUS can reduce ovarian tissue injury. We demonstrated that LIPUS can relieve ovarian fibrosis by inhibiting TGF-β1/Smads pathway. Meanwhile, it can reduce the oxidative damage and reduced the mRNA levels of proinflammatory cytokines caused by chemotherapy.

CONCLUSION

LIPUS can reduce the toxic effects of chemotherapy drugs on ovaries, inhibit ovarian fibrosis, reduce the inflammatory response, and redcue the oxidative damage, reduce follicle depletion and to maintain the number of follicle pools.

Effect of GLP-1 Receptor Agonist on Ischemia Reperfusion Injury in Rats with Metabolic Syndrome

Metabolic syndrome (MetS) represents an important factor that increases the risk of myocardial infarction, and more severe complications. Glucagon Like Peptide-1 Receptor Agonists (GLP-1RAs) exhibit cardioprotective potential, but their efficacy in MetS-related myocardial dysfunction has not been fully explored. Therefore, we aimed to assess the effects of exenatide and dulaglutide on heart function and redox balance in MetS-induced rats. Twenty-four Wistar albino rats with induced MetS were divided into three groups: MetS, exenatide-treated (5 µg/kg), dulaglutide-treated (0.6 mg/kg). After 6 weeks of treatment, in vivo heart function was assessed via echocardiography, while ex vivo function was evaluated using a Langendorff apparatus to simulate ischemia-reperfusion injury. Heart tissue samples were analyzed histologically, and oxidative stress biomarkers were measured spectrophotometrically from the coronary venous effluent. Both exenatide and dulaglutide significantly improved the ejection fraction by 3% and 7%, respectively, compared to the MetS group. Histological analyses corroborated these findings, revealing a reduction in the cross-sectional area of cardiomyocytes by 11% in the exenatide and 18% in the dulaglutide group, indicating reduced myocardial damage in GLP-1RA-treated rats. Our findings suggest strong cardioprotective potential of GLP-1RAs in MetS, with dulaglutide showing a slight advantage. Thus, both exenatide and dulaglutide are potentially promising targets for cardioprotection and reducing mortality in MetS patients.

Targeting mitochondrial quality control for diabetic cardiomyopathy: Therapeutic potential of hypoglycemic drugs

Diabetic cardiomyopathy is a chronic cardiovascular complication caused by diabetes that is characterized by changes in myocardial structure and function, ultimately leading to heart failure and even death. Mitochondria serve as the provider of energy to cardiomyocytes, and mitochondrial dysfunction plays a central role in the development of diabetic cardiomyopathy. In response to a series of pathological changes caused by mitochondrial dysfunction, the mitochondrial quality control system is activated. The mitochondrial quality control system (including mitochondrial biogenesis, fusion and fission, and mitophagy) is core to maintaining the normal structure of mitochondria and performing their normal physiological functions. However, mitochondrial quality control is abnormal in diabetic cardiomyopathy, resulting in insufficient mitochondrial fusion and excessive fission within the cardiomyocyte, and fragmented mitochondria are not phagocytosed in a timely manner, accumulating within the cardiomyocyte resulting in cardiomyocyte injury. Currently, there is no specific therapy or prevention for diabetic cardiomyopathy, and glycemic control remains the mainstay. In this review, we first elucidate the pathogenesis of diabetic cardiomyopathy and explore the link between pathological mitochondrial quality control and the development of diabetic cardiomyopathy. Then, we summarize how clinically used hypoglycemic agents (including sodium-glucose cotransport protein 2 inhibitions, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, thiazolidinediones, metformin, and α-glucosidase inhibitors) exert cardioprotective effects to treat and prevent diabetic cardiomyopathy by targeting the mitochondrial quality control system. In addition, the mechanisms of complementary alternative therapies, such as active ingredients of traditional Chinese medicine, exercise, and lifestyle, targeting mitochondrial quality control for the treatment of diabetic cardiomyopathy are also added, which lays the foundation for the excavation of new diabetic cardioprotective drugs.

RUNX1 facilitates heart failure progression through regulating TGF-β-induced cardiac remodeling

Background

Heart failure is caused by acute or chronic cardiovascular diseases with limited treatments and unclear pathogenesis. Therefore, it is urgent to explore new therapeutic targets and reveal new pathogenesis for heart failure.

Methods

We carried out heart failure animal model by transverse aortic arch constriction (TAC) in mice. The left ventricular internal diameter diastole (LVIDd), left ventricular internal diameter systole (LVIDs), and ejection fraction (EF) value were detected using ultrasound and myocardial fibrosis was evaluated by Masson stain assay. Cell apoptosis in myocardial tissues were detected by TUNEL immunofluorescence stain. Signal pathway analysis was performed by dual-luciferase reporter assay and western blot.

Results

Our results showed that inhibition of RUNX1 led to remission of cardiac enlargement induced by TAC in mice. Inhibition of RUNX1 also caused raise of EF and FS value under TAC-induced condition. Besides, RUNX1 inhibition mice showed decreased myocardial fibrosis area under TAC-induced condition. RUNX1 inhibition caused decrease of apoptotic cell rate in myocardial tissues under TAC. Interestingly, we found that RUNX1 could promote the activation of TGF-β/Smads in dual-luciferase reporter assay.

Interpretation

We illustrated that RUNX1 could be considered as a new regulator of myocardial remodeling by activating TGF-β/Smads signaling. Based on this, we concluded that RUNX1 may be developed as a new therapeutic target against heart failure in the future. In addition, this study also provide a new insight for the etiological study on heart failure.

Glucagon-Like Peptide-1 Protects Against Atrial Fibrillation and Atrial Remodeling in Type 2 Diabetic Mice

Atrial fibrillation (AF) is highly prevalent in type 2 diabetes where it increases morbidity and mortality. Glucagon-like peptide (GLP)-1 receptor agonists are used in the treatment of type 2 diabetes (T2DM), but their effects on AF in T2DM are poorly understood. The present study demonstrates type 2 diabetic db/db mice are highly susceptible to AF in association with atrial electrical and structural remodeling. GLP-1, as well as the long-acting GLP-1 analogue liraglutide, reduced AF and prevented atrial remodeling in db/db mice. These data suggest that GLP-1 and related analogues could protect against AF in patients with T2DM.

A novel caffeic acid derivative prevents angiotensin II-induced cardiac remodeling

Differentiation of cardiac fibroblasts into myofibroblasts is a critical event in the progression of cardiac fibrosis that causes pathological cardiac remodeling. Cardiac fibrosis is a hallmark of heart disease and is associated with a stiff myocardium and heart failure. This study investigated the effect of caffeic acid ethanolamide (CAEA), a novel caffeic acid derivative, on cardiac remodeling. Angiotensin (Ang) II was used to induce cardiac remodeling both in cell and animal studies. Treating cardiac fibroblast with CAEA in Ang II-exposed cell cultures reduced the expression of fibrotic marker α-smooth muscle actin (α-SMA) and collagen and the production of superoxide, indicating that CAEA inhibited the differentiation of fibroblast into myofibroblast after Ang II exposure. CAEA protects against Ang II-induced cardiac fibrosis and dysfunction in vivo, characterized by the alleviation of collagen accumulation and the recovery of ejection fraction. In addition, CAEA decreased Ang II-induced transforming growth factor-β (TGF-β) expression and reduced NOX4 expression and oxidative stress in a SMAD-dependent pathway. CAEA participated in the regulation of Ang II-induced TGF-β/SMAD/NOX4 signaling to prevent the differentiation of fibroblast into myofibroblast and thus exerted a cardioprotective effect. Our data support the administration of CAEA as a viable method for preventing the progression of Ang II-induced cardiac remodeling.

Engineered probiotics Clostridium butyricum-pMTL007-GLP-1 improves blood pressure via producing GLP-1 and modulating gut microbiota in spontaneous hypertension rat models

Hypertension is a significant risk factor of cardiovascular diseases (CVDs) with high prevalence worldwide, the current treatment has multiple adverse effects and requires continuous administration. The glucagon-like peptide-1 receptor (GLP-1R) agonists have shown great potential in treating diabetes mellitus, neurodegenerative diseases, obesity and hypertension. Butyric acid is a potential target in treating hypertension. Yet, the application of GLP-1 analogue and butyric acid in reducing blood pressure and reversing ventricular hypertrophy remains untapped. In this study, we combined the therapeutic capability of GLP-1 and butyric acid by transforming Clostridium butyricum (CB) with recombinant plasmid pMTL007 encoded with hGLP gene to construct the engineered probiotics Clostridium butyricum-pMTL007-GLP-1 (CB-GLP-1). We used spontaneous hypertensive rat (SHR) models to evaluate the positive effect of this strain in treating hypertension. The results revealed that the intragastric administration of CB-GLP-1 had markedly reduced blood pressure and improved cardiac marker ACE2, AT2R, AT1R, ANP, BNP, β-MHC, α-SMA and activating AMPK/mTOR/p70S6K/4EBP1 signalling pathway. The high-throughput sequencing further demonstrated that CB-GLP-1 treatments significantly improved the dysbiosis in the SHR rats via downregulating the relative abundance of Porphyromonadaceae at the family level and upregulating Lactobacillus at the genus level. Hence, we concluded that the CB-GLP-1 greatly improves blood pressure and cardiomegaly by restoring the gut microbiome and reducing ventricular hypertrophy in rat models. This is the first time using engineered CB in treating hypertension, which provides a new idea for the clinical treatment of hypertension.

The postprandial actions of GLP-1 receptor agonists: The missing link for cardiovascular and kidney protection in type 2 diabetes

Recent clinical trials in people with type 2 diabetes have demonstrated beneficial actions on heart and kidney outcomes following treatment with GLP-1RAs. In part, these actions are consistent with improved glucose control and significant weight loss. But GLP-1RAs may also have additive benefits by improving postprandial dysmetabolism. In diabetes, dysregulated postprandial nutrient excursions trigger inflammation, oxidative stress, endothelial dysfunction, thrombogenicity, and endotoxemia; alter hormone levels; and modulate cardiac output and regional blood and lymphatic flow. In this perspective, we explore the actions of GLP-1RAs on the postprandial state and their potential role in end-organ benefits observed in recent trials.

Cardiovascular Protection with a Long-Acting GLP-1 Receptor Agonist Liraglutide: An Experimental Update

Angiotensin II (Ang II), a peptide hormone generated as part of the renin-angiotensin system, has been implicated in the pathophysiology of many cardiovascular diseases such as peripheral artery disease, heart failure, hypertension, coronary artery disease and other conditions. Liraglutide, known as an incretin mimetic, is one of the glucagon-like peptide-1 (GLP-1) receptor agonists, and has been proven to be effective in the treatment of cardiovascular disorders beyond adequate glycemic control. The objective of this review is to compile our recent experimental outcomes-based studies, and provide an overview the cardiovascular protection from liraglutide against Ang II- and pressure overload-mediated deleterious effects on the heart. In particular, the mechanisms of action underlying the inhibition of oxidative stress, vascular endothelial dysfunction, hypertension, cardiac fibrosis, left ventricular hypertrophy and heart failure with liraglutide are addressed. Thus, we support the notion that liraglutide continues to be a useful add-on therapy for the management of cardiovascular diseases.

NOX Dependent ROS Generation and Cell Metabolism

Reactive oxygen species (ROS) represent a group of high reactive molecules with dualistic natures since they can induce cytotoxicity or regulate cellular physiology. Among the ROS, the superoxide anion radical (O2·-) is a key redox signaling molecule prominently generated by the NADPH oxidase (NOX) enzyme family and by the mitochondrial electron transport chain. Notably, altered redox balance and deregulated redox signaling are recognized hallmarks of cancer and are involved in malignant progression and resistance to drugs treatment. Since oxidative stress and metabolism of cancer cells are strictly intertwined, in this review, we focus on the emerging roles of NOX enzymes as important modulators of metabolic reprogramming in cancer. The NOX family includes seven isoforms with different activation mechanisms, widely expressed in several tissues. In particular, we dissect the contribute of NOX1, NOX2, and NOX4 enzymes in the modulation of cellular metabolism and highlight their potential role as a new therapeutic target for tumor metabolism rewiring.

Peptide mediated therapy in fibrosis: Mechanisms, advances and prospects

Fibrosis, a disease characterized by an excess accumulation of extracellular matrix components, could lead to organ failure and death, and is to blame for up to 45 % of all fatalities in developed nations. These disorders all share the common trait of an unchecked and increasing accumulation of fibrotic tissue in the affected organs, which leads to their malfunction and eventual failure, even if their underlying causes are highly diverse and, in some cases, remain unclear. Numerous studies have identified activated myofibroblasts as the common cellular elements ultimately responsible for the replacement of normal tissues with nonfunctional fibrotic tissue. The transforming growth factor-β pathway, for instance, plays a significant role in practically all kinds of fibrosis. However, there is no specific drug for the treatment of fibrosis, several medications with anti-hepatic fibrosis properties are still in the research and development stages. Peptide, which refers to a substance consisting of 2-50 amino acids, is characterized by structural diversity, low toxicity, biological activities, easy absorption, specific targeting, few side effects, and has been proven to be effective in anti-fibrosis. Here, we summarized various anti-fibrosis peptides in fibrosis including the liver, lungs, kidneys, and other organs. This review will provide a new insight into peptide mediated anti-fibrosis and is helpful to creation of antifibrotic medications.

Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA)-mediated ER stress crosstalk with autophagy is involved in tris(2-chloroethyl) phosphate stress-induced cardiac fibrosis

Excessive organophosphate flame retardant (OPFR) use in consumer products has been reported to increase human disease susceptibility. However, the adverse effects of tris(2-chloroethyl) phosphate (TCEP) (a chlorinated alkyl OPFR) on the heart remain unknown. In this study, we tested whether cardiac fibrosis occurred in animal models of TCEP (10 mg/kg b.w./day) administered continuously by gavage for 30 days and evaluated the specific role of sarco/endoplasmic reticulum Ca²⁺ ATPase (SERCA). First, we confirmed that TCEP could trigger cardiac fibrosis by histopathological observation and cardiac fibrosis markers. We further verified that cardiac fibrosis occurred in animal models of TCEP exposure accompanied by SERCA2a, SERCA2b and SERCA2c downregulation. Notably, inductively coupled plasma-mass spectrometry (ICP-MS) analysis revealed that the cardiac concentrations of Ca²⁺ increased by 45.3% after TCEP exposure. Using 4-Isopropoxy-N-(2-methylquinolin-8-yl)benzamide (CDN1163, a small molecule SERCA activator), we observed that Ca²⁺ overload and subsequent cardiac fibrosis caused by TCEP were both alleviated. Simultaneously, the protein levels of endoplasmic reticulum (ER) markers (protein kinase R-like endoplasmic reticulum kinase (PERK), inositol requiring protein 1α (IRE1α), eukaryotic initiation factor 2 α (eIF2α)) were upregulated by TCEP, which could be abrogated by CDN1163 pretreatment. Furthermore, we observed that CDN1163 supplementation prevented overactive autophagy induced by TCEP in the heart. Mechanistically, TCEP could lead to Ca²⁺ overload by inhibiting the expression of SERCA, thereby triggering ER stress and overactive autophagy, eventually resulting in cardiac fibrosis. Together, our results suggest that the Ca²⁺ overload/ER stress/autophagy axis can act as a driver of cardiotoxicity induced by TCEP.