Dominant negative Ras attenuates pathological ventricular remodeling in pressure overload cardiac hypertrophy

MEK Inhibition for RASopathy-Associated Hypertrophic Cardiomyopathy: Clinical Application of a Basic Concept

The term "RASopathies" designates a group of developmental syndromes that are caused by activating variants of the rat sarcoma virus protein (RAS)/mitogen-activated protein kinase (MAPK) cascade. The most prevalent clinical diagnosis is Noonan syndrome, and other, less prevalent conditions include Noonan syndrome with multiple lentigines, Costello syndrome, cardiofaciocutaneous syndrome, and others. Hypertrophic cardiomyopathy occurs in 10% of these patients and can be severe and life-threating. Recently, repurposing of medications inhibiting the RAS/MAPK on a compassionate use basis has emerged as a promising concept to improve the outcome of these patients. Herein, we specifically review the role of the RAS/MAPK pathway in RASopathy-associated cardiomyopathy, and discuss the role of small-molecule inhibition in the treatment of this condition. We describe how drug repurposing of trametinib (mitogen-activated protein/extracellular signal-regulated kinase inhibition) and sirolimus/everolimus (mammalian target of rapamycin inhibition) was performed, how genotype-specific therapies are chosen and followed, as well as initial outcomes from early case series. Finally, we lay out the challenges and opportunities for trials that aim to quantify the benefits of this approach.

Role of gene therapy in treatment of cancer with craniofacial regeneration-current molecular strategies, future perspectives, and challenges: a narrative review

Gene therapy involves the introduction of foreign genetic material into host tissue to alter the expression of genetic products. Gene therapy represents an opportunity to alter the course of various diseases. Hence, genetic products utilizing safe and reliable vectors with improved biotechnology will play a critical role in the treatment of various diseases in the future. This review summarizes various important vectors for gene therapy along with modern techniques for potential craniofacial regeneration using gene therapy. This review also explains current molecular approaches for the management and treatment of cancer using gene therapy. The existing literature was searched to find studies related to gene therapy and its role in craniofacial regeneration and cancer treatment. Various databases such as PubMed, Science Direct, Scopus, Web of Science, and Google Scholar were searched for English language articles using the keywords "gene therapy," "gene therapy in present scenario," "gene therapy in cancer," "gene therapy and vector," "gene therapy in diseases," and "gene therapy and molecular strategies."

Gene Therapy for Regenerative Medicine

The development of biological methods over the past decade has stimulated great interest in the possibility to regenerate human tissues. Advances in stem cell research, gene therapy, and tissue engineering have accelerated the technology in tissue and organ regeneration. However, despite significant progress in this area, there are still several technical issues that must be addressed, especially in the clinical use of gene therapy. The aims of gene therapy include utilising cells to produce a suitable protein, silencing over-producing proteins, and genetically modifying and repairing cell functions that may affect disease conditions. While most current gene therapy clinical trials are based on cell- and viral-mediated approaches, non-viral gene transfection agents are emerging as potentially safe and effective in the treatment of a wide variety of genetic and acquired diseases. Gene therapy based on viral vectors may induce pathogenicity and immunogenicity. Therefore, significant efforts are being invested in non-viral vectors to enhance their efficiency to a level comparable to the viral vector. Non-viral technologies consist of plasmid-based expression systems containing a gene encoding, a therapeutic protein, and synthetic gene delivery systems. One possible approach to enhance non-viral vector ability or to be an alternative to viral vectors would be to use tissue engineering technology for regenerative medicine therapy. This review provides a critical view of gene therapy with a major focus on the development of regenerative medicine technologies to control the in vivo location and function of administered genes.

CRISPR-Cas9-Based Technology and Its Relevance to Gene Editing in Parkinson's Disease

Parkinson’s disease (PD) and other chronic and debilitating neurodegenerative diseases (NDs) impose a substantial medical, emotional, and financial burden on individuals and society. The origin of PD is unknown due to a complex combination of hereditary and environmental risk factors. However, over the last several decades, a significant amount of available data from clinical and experimental studies has implicated neuroinflammation, oxidative stress, dysregulated protein degradation, and mitochondrial dysfunction as the primary causes of PD neurodegeneration. The new gene-editing techniques hold great promise for research and therapy of NDs, such as PD, for which there are currently no effective disease-modifying treatments. As a result, gene therapy may offer new treatment options, transforming our ability to treat this disease. We present a detailed overview of novel gene-editing delivery vehicles, which is essential for their successful implementation in both cutting-edge research and prospective therapeutics. Moreover, we review the most recent advancements in CRISPR-based applications and gene therapies for a better understanding of treating PD. We explore the benefits and drawbacks of using them for a range of gene-editing applications in the brain, emphasizing some fascinating possibilities.

Cardiac-specific deletion of FDPS induces cardiac remodeling and dysfunction by enhancing the activity of small GTP-binding proteins

The mevalonate pathway is essential for cholesterol biosynthesis. Previous studies have suggested that the key enzyme in this pathway, farnesyl diphosphate synthase (FDPS), regulates the cardiovascular system. We used human samples and mice that were deficient in cardiac FDPS (c-Fdps^-/- mice) to investigate the role of FDPS in cardiac homeostasis. Cardiac function was assessed using echocardiography. Left ventricles were examined and tested for histological and molecular markers of cardiac remodeling. Our results showed that FDPS levels were downregulated in samples from patients with cardiomyopathy. Furthermore, c-Fdps^-/- mice exhibited cardiac remodeling and dysfunction. This dysfunction was associated with abnormal activation of Ras and Rheb, which may be due to the accumulation of geranyl pyrophosphate. Activation of Ras and Rheb stimulated downstream mTOR and ERK pathways. Moreover, administration of farnesyltransferase inhibitors attenuated cardiac remodeling and dysfunction in c-Fdps^-/- mice. These results indicate that FDPS plays an important role in cardiac homeostasis. Deletion of FDPS stimulates the downstream mTOR and ERK signaling pathways, resulting in cardiac remodeling and dysfunction. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Molecules linked to Ras signaling as therapeutic targets in cardiac pathologies

Abstract

The Ras family of small Guanosine Triphosphate (GTP)-binding proteins (G proteins) represents one of the main components of intracellular signal transduction required for normal cardiac growth, but is also critically involved in the development of cardiac hypertrophy and heart failure. The present review provides an update on the role of the H-, K- and N-Ras genes and their related pathways in cardiac diseases. We focus on cardiac hypertrophy and heart failure, where Ras has been studied the most. We also review other cardiac diseases, like genetic disorders related to Ras. The scope of the review extends from fundamental concepts to therapeutic applications. Although the three Ras genes have a nearly identical primary structure, there are important functional differences between them: H-Ras mainly regulates cardiomyocyte size, whereas K-Ras regulates cardiomyocyte proliferation. N-Ras is the least studied in cardiac cells and is less associated to cardiac defects. Clinically, oncogenic H-Ras causes Costello syndrome and facio-cutaneous-skeletal syndromes with hypertrophic cardiomyopathy and arrhythmias. On the other hand, oncogenic K-Ras and alterations of other genes of the Ras-Mitogen-Activated Protein Kinase (MAPK) pathway, like Raf, cause Noonan syndrome and cardio-facio-cutaneous syndromes characterized by cardiac hypertrophy and septal defects. We further review the modulation by Ras of key signaling pathways in the cardiomyocyte, including: (i) the classical Ras-Raf-MAPK pathway, which leads to a more physiological form of cardiac hypertrophy; as well as other pathways associated with pathological cardiac hypertrophy, like (ii) The SAPK (stress activated protein kinase) pathways p38 and JNK; and (iii) The alternative pathway Raf-Calcineurin-Nuclear Factor of Activated T cells (NFAT). Genetic alterations of Ras isoforms or of genes in the Ras-MAPK pathway result in Ras-opathies, conditions frequently associated with cardiac hypertrophy or septal defects among other cardiac diseases. Several studies underline the potential role of H- and K-Ras as a hinge between physiological and pathological cardiac hypertrophy, and as potential therapeutic targets in cardiac hypertrophy and failure.

Graphic abstract

The Ras (Rat Sarcoma) gene family is a group of small G proteins

Ras is regulated by growth factors and neurohormones affecting cardiomyocyte growth and hypertrophy

Ras directly affects cardiomyocyte physiological and pathological hypertrophy

Genetic alterations of Ras and its pathways result in various cardiac phenotypes

Ras and its pathway are differentially regulated in acquired heart disease

Ras modulation is a promising therapeutic target in various cardiac conditions.

Evolutionary Timeline of Genetic Delivery and Gene Therapy

There are more than 3,500 genes that are being linked to hereditary diseases or correlated with an elevated risk of certain illnesses. As an alternative to conventional treatments with small molecule drugs, gene therapy has arisen as an effective treatment with the potential to not just alleviate disease conditions but also cure them completely. In order for these treatment regimens to work, genes or editing tools intended to correct diseased genetic material must be efficiently delivered to target sites. There have been many techniques developed to achieve such a goal. In this article, we systematically review a variety of gene delivery and therapy methods that include physical methods, chemical and biochemical methods, viral methods, and genome editing. We discuss their historical discovery, mechanisms, advantages, limitations, safety, and perspectives.

Rap1GAP Mediates Angiotensin II-Induced Cardiomyocyte Hypertrophy by Inhibiting Autophagy and Increasing Oxidative Stress

Abnormal autophagy and oxidative stress contribute to angiotensin II- (Ang II-) induced cardiac hypertrophy and heart failure. We previously showed that Ang II increased Rap1GAP gene expression in cardiomyocytes associated with hypertrophy and autophagy disorders. Using real-time PCR and Western blot, we found that Rap1GAP expression was increased in the heart of Sprague Dawley (SD) rats infused by Ang II compared with saline infusion and in Ang II vs. vehicle-treated rat neonatal cardiomyocytes. Overexpression of Rap1GAP in cultured cardiomyocytes exacerbated Ang II-induced cardiomyocyte hypertrophy, reactive oxygen species (ROS) generation, and cell apoptosis and inhibited autophagy. The increased oxidative stress caused by Rap1GAP overexpression was inhibited by the treatment of autophagy agonists. Knockdown of Rap1GAP by siRNA markedly attenuated Ang II-induced cardiomyocyte hypertrophy and oxidative stress and enhanced autophagy. The AMPK/AKT/mTOR signaling pathway was inhibited by overexpression of Rap1GAP and activated by the knockdown of Rap1GAP. These results show that Rap1GAP-mediated pathway might be a new mechanism of Ang II-induced cardiomyocyte hypertrophy, which could be a potential target for the future treatment of cardiac hypertrophy and heart failure.

Low-dose Dasatinib Ameliorates Hypertrophic Cardiomyopathy in Noonan Syndrome with Multiple Lentigines

Purpose

Noonan syndrome with multiple lentigines (NSML) is an autosomal dominant disorder presenting with hypertrophic cardiomyopathy (HCM). Up to 85% of NSML cases are caused by mutations in the PTPN11 gene that encodes for the Src homology 2 (SH2) domain-containing protein tyrosine phosphatase 2 (SHP2). We previously showed that low-dose dasatinib protects from the development of cardiac fibrosis in a mouse model of NSML harboring a Ptpn11^Y279C mutation. This study is performed to determine the pharmacokinetic (PK) and pharmacodynamic (PD) properties of a low-dose of dasatinib in NSML mice and to determine its effectiveness in ameliorating the development of HCM.

Methods

Dasatinib was administered intraperitoneally into NSML mice with doses ranging from 0.05 to 0.5 mg/kg. PK parameters of dasatinib in NSML mice were determined. PD parameters were obtained for biochemical analyses from heart tissue. Dasatinib-treated NSML mice (0.1 mg/kg) were subjected to echocardiography and assessment of markers of HCM by qRT-PCR. Transcriptome analysis was performed from the heart tissue of low-dose dasatinib-treated mice.

Results

Low-dose dasatinib exhibited PK properties that were linear across doses in NSML mice. Dasatinib treatment of between 0.05 and 0.5 mg/kg in NSML mice yielded an exposure-dependent inhibition of c-Src and PZR tyrosyl phosphorylation and inhibited AKT phosphorylation. We found that doses as low as 0.1 mg/kg of dasatinib prevented HCM in NSML mice. Transcriptome analysis identified differentially expressed HCM-associated genes in the heart of NSML mice that were reverted to wild type levels by low-dose dasatinib administration.

Conclusion

These data demonstrate that low-dose dasatinib exhibits desirable therapeutic PK properties that is sufficient for effective target engagement to ameliorate HCM progression in NSML mice. These data demonstrate that low-dose dasatinib treatment may be an effective therapy against HCM in NSML patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10557-021-07169-z.

Role of extracellular signal-regulated kinase 1/2 signaling underlying cardiac hypertrophy

Cardiac hypertrophy is the result of increased myocardial cell size responding to an increased workload and developmental signals. These extrinsic and intrinsic stimuli as key drivers of cardiac hypertrophy have spurred efforts to target their associated signaling pathways. The extracellular signal-regulated kinases 1/2 (ERK1/2), as an essential member of mitogen-activated protein kinases (MAPKs), has been widely recognized for promoting cardiac growth. Several modified transgenic mouse models have been generated through either affecting the upstream kinase to change ERK1/2 activity, manipulating the direct role of ERK1/2 in the heart, or targeting phosphatases or MAPK scaffold proteins to alter total ERK1/2 activity in response to an increased workload. Using these models, both regulation of the upstream events and modulation of each isoform and indirect effector could provide important insights into how ERK1/2 modulates cardiomyocyte biology. Furthermore, a plethora of compounds, inhibitors, and regulators have emerged in consideration of ERK, or its MAPK kinases, are possible therapeutic targets against cardiac hypertrophic diseases. Herein, is a review of the available evidence regarding the exact role of ERK1/2 in regulating cardiac hypertrophy and a discussion of pharmacological strategy for treatment of cardiac hypertrophy.

BMI1 in the heart: Novel functions beyond tumorigenesis

The BMI1 protein, a member of the PRC1 family, is a well recognised transcriptional suppressor and has the capability of maintaining the self-renewal and proliferation of tissue-specific stem cells. Numerous studies have established that BMI1 is highly expressed in a variety of malignant cancers and serves as a key regulator in the tumorigenesis process. However, our understanding of BMI1 in terminally differentiated organs, such as the heart, is relatively nascent. Importantly, emerging data support that, beyond the tumor, BMI1 is also expressed in the heart tissue and indeed exerts profound effects in various cardiac pathological conditions. This review gives a summary of the novel functions of BMI1 in the heart, including BMI1-positive cardiac stem cells and BMI1-mediated signaling pathways, which are involved in the response to various cardiac pathological stimuli. Besides, we summarize the recent progress of BMI1 in some novel and rapidly developing cardiovascular therapies. Furtherly, we highlight the properties of BMI1, a therapeutic target proved effective in cancer treatment, as a promising target to alleviate cardiovascular diseases.

Inhibition of the NFATc4/ERK/AKT Pathway and Improvement of Thiol-Specific Oxidative Stress by Dronedarone Possibly Secondary to the Reduction of Blood Pressure in an Animal Model of Ventricular Hypertrophy

Untreated chronic hypertension causes left ventricular hypertrophy, which is related to the occurrence of atrial fibrillation. Dronedarone is an antiarrhythmic agent recently approved for atrial fibrillation. Our group previously demonstrated that dronedarone produced an early regression of left ventricular hypertrophy after 14 days of treatment in an experimental study. In this study, we analyze the possible mechanisms responsible for this effect. Ten-month-old male spontaneously hypertensive rats (SHRs, n = 16) were randomly divided into therapy groups: SHR-D, which received dronedarone, and hypertensive controls, SHR, which received saline. Ten-month-old male Wistar Kyoto rats (WKY, n = 8), which also received a saline solution, were selected as normotensive controls. After 14 days of treatment, echocardiographic measurements of the left ventricle were performed, blood samples were collected for thiol-specific oxidative stress analysis, and the left ventricles were processed for western blot analysis. Dronedarone significantly lowered the left ventricular mass index and relative wall thickness compared with the SHR control group, and no differences were observed between the SHR-D group and the WKY rats. Interestingly, the SHR-D group showed significantly decreased levels of nuclear factor of activated T cells 4 (p-NFATc4), extracellular-signal-regulated kinase 1/2 (p-ERK1/2), and protein kinase B (p-AKT) compared with the hypertensive controls without statistical differences when compared with the WKY rats. Moreover, the SHR control group showed elevated thiolated protein levels and protein thiolation index (PTI) compared with the WKY rats. After treatment with dronedarone, both parameters decreased with respect to the SHR control group until reaching similar levels to the WKY rats. Our study suggests that dronedarone produces inhibition of the NFATc4/ERK/AKT pathway and improvement of thiol-specific oxidative stress possibly secondary to the reduction of blood pressure in an animal model of ventricular hypertrophy.

A current view of G protein-coupled receptor - mediated signaling in pulmonary hypertension: finding opportunities for therapeutic intervention

Pathological vascular remodeling is observed in various cardiovascular diseases including pulmonary hypertension (PH), a disease of unknown etiology that has been characterized by pulmonary artery vasoconstriction, right ventricular hypertrophy, vascular inflammation, and abnormal angiogenesis in pulmonary circulation. G protein-coupled receptors (GPCRs) are the largest family in the genome and widely expressed in cardiovascular system. They regulate all aspects of PH pathophysiology and represent therapeutic targets. We overview GPCRs function in vasoconstriction, vasodilation, vascular inflammation-driven remodeling and describe signaling cross talk between GPCR, inflammatory cytokines, and growth factors. Overall, the goal of this review is to emphasize the importance of GPCRs as critical signal transducers and targets for drug development in PH.

Different Methods of Delivering CRISPR/Cas9 Into Cells

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system (Cas) is comprised of repetitive bases followed by short fragments of DNA from a previously invading organism that provide immunity to the most prokaryotic organisms. An RNA-dependent spacer is required for CRISPR/Cas9 to recognize the target DNA. Delivery of the CRISPR/Cas9-guide RNA (gRNA) complex to any cell results in modification of the target sequence. The CRISPR/Cas9-mediated genome editing technique is currently in the spotlight and has several research interests, including molecular medicine and agriculture. There are several factors that hinder the delivery of this complex, such as the large size of the plasmid or high dosage of the chemical agent. There are several methods available to deliver CRISPR/Cas9 and its components to the target cells. It includes viral, non-viral and physical methods to deliver plasmid or ribonucleoprotein (RNP) of CRISPR components. But in vivo CRISPR/Cas9 delivery remains challenging to the researchers due to insertional mutagenesis, targeted delivery, immunogenicity, and off-targets. However, studies suggesting that the CRISPR/Cas9-RNP delivery can overcome these hurdles. Here, we review the various methods for delivery of CRISPR/Cas9 and gRNA to several cell lines, highlighting the limitations of each approach, and suggest possible alternative methods.

Inhibition of mevalonate pathway prevents ischemia-induced cardiac dysfunction in rats via RhoA-independent signaling pathway

AIM

We previously demonstrated that anoxia-mediated Ca²⁺ handling dysfunction could be ameliorated through inhibition of mevalonate pathway via RhoA- and Ras-related mechanisms in H9c2 cells. In this study, we further explored whether inhibition of mevalonate pathway is associated with cardiac remodeling and dysfunction in ischemic cardiomyopathy, and discussed the possible role of Ras, Rac and RhoA in cardiac dysfunction.

METHODS

We investigated the role of mevalonate pathway in cardiac remodeling and cardiomyocyte Ca²⁺ handling proteins expression in a rat model of cardiac dysfunction due to myocardial infarction (MI). After MI, adult male Sprague-Dawley rats were treated with drugs that antagonize key components in mevalonate pathway, including 3-hydroxy-3-methylglutaryl-CoA reductase, farnesyl pyrophosphate synthase, and Rho-kinase for 10 weeks. The protein expression of ryanodine receptor 2 (RyR2), sarcoplasmic reticulum Ca²⁺ ATPase (SERCA) 2a, phospholamban (PLB), phospho-PLB at serine-16 (PSer16-PLB), FKBP12.6, and RhoA as well as RyR2 and FKBP12.6 mRNA levels was evaluated.

RESULTS

Rosuvastatin and alendronate treatment prevented myocardial remodeling, improved cardiac function and reduced infarct size. Furthermore, rosuvastatin and alendronate promoted an increase in the protein expression of SERCA2a and PSer16-PLB/PLB ratio as well as partially restored the RyR2 and FKBP12.6 gene and protein expression. Fasudil failed to exert these beneficial effects.

CONCLUSIONS

These findings indicate that mevalonate pathway inhibition by rosuvastatin and alendronate prevents cardiac remodeling and dysfunction possibly through RhoA-independent mechanisms.

A multidimensional sight on cardiac failure: uncovered from structural to molecular level

Heart failure is one of the leading causes of death, with high mortality rate within 5 years after diagnosis. Treatment and prognosis options for heart failure primarily targeted on hemodynamic and neurohumoral components that drive progressive deterioration of the heart. However, given the multifactorial background that eventually leads to the "phenotype" named heart failure, better insight into the various components may lead to personalized treatment opportunities. Indeed, currently used criteria to diagnose and/or classify heart failure are possibly too focused on phenotypic improvement rather than the molecular driver of the disease and could therefore be further refined by integrating the leap of molecular and cellular knowledge. The ambiguity of the ejection fraction-based classification criteria became evident with development of advanced molecular techniques and the dawn of omics disciplines which introduced the idea that disease is caused by a myriad of cellular and molecular processes rather than a single event or pathway. The fact that different signaling pathways may underlie similar clinical manifestations calls for a more holistic study of heart failure. In this context, the systems biology approach can offer a better understanding of how different components of a system are altered during disease and how they interact with each other, potentially leading to improved diagnosis and classification of this condition. This review is aimed at addressing heart failure through a multilayer approach that covers individually some of the anatomical, morphological, functional, and tissue aspects, with focus on cellular and subcellular features as an alternative insight into new therapeutic opportunities.

Adenovirus-Mediated Gene Delivery: Potential Applications for Gene and Cell-Based Therapies in the New Era of Personalized Medicine

With rapid advances in understanding molecular pathogenesis of human diseases in the era of genome sciences and systems biology, it is anticipated that increasing numbers of therapeutic genes or targets will become available for targeted therapies. Despite numerous setbacks, efficacious gene and/or cell-based therapies still hold the great promise to revolutionize the clinical management of human diseases. It is wildly recognized that poor gene delivery is the limiting factor for most in vivo gene therapies. There has been a long-lasting interest in using viral vectors, especially adenoviral vectors, to deliver therapeutic genes for the past two decades. Among all currently available viral vectors, adenovirus is the most efficient gene delivery system in a broad range of cell and tissue types. The applications of adenoviral vectors in gene delivery have greatly increased in number and efficiency since their initial development. In fact, among over 2,000 gene therapy clinical trials approved worldwide since 1989, a significant portion of the trials have utilized adenoviral vectors. This review aims to provide a comprehensive overview on the characteristics of adenoviral vectors, including adenoviral biology, approaches to engineering adenoviral vectors, and their applications in clinical and pre-clinical studies with an emphasis in the areas of cancer treatment, vaccination and regenerative medicine. Current challenges and future directions regarding the use of adenoviral vectors are also discussed. It is expected that the continued improvements in adenoviral vectors should provide great opportunities for cell and gene therapies to live up to its enormous potential in personalized medicine.

Inhibition of farnesyl pyrophosphate synthase improves pressure overload induced chronic cardiac remodeling

Farnesyl pyrophosphate synthase (FPPS) is a key enzyme in the mevalonate pathway. In our previous studies, we find that inhibition of FPPS attenuates angiotensin II-induced cardiac hypertrophy and fibrosis by suppressing RhoA while FPPS and Ras are up-regulated in pressure overload rats. In this study, we evaluate the effects and mechanisms of FPPS inhibition in pressure overload mice. Male FPPS-small interfering RNA (SiRNA) transgenic (Tg) mice and non-transgenic littermate control (NLC) were randomly divided into suprarenal abdominal aortic constriction (AAC) group and sham operation group. 12 weeks following AAC, mice were sacrificed by cervical dislocation. Histological and echocardiographic assessments showed that inhibition of FPPS improved chronic cardiac remodeling which was induced by AAC. The reductions of Ras farnesylation and GTP-Ras, as well as their downstream extracellular signal-related kinases 1/2 (ERK1/2) expression were observed in the heart of Tg-AAC mice compared with NLC-AAC mice, along with the reduction of fetal gene expression. We provide here important experimental evidence that inhibition of FPPS improves AAC induced chronic cardiac remodeling and fibrosis by the reduction of farnesylated Ras and the downregulation of Ras-ERK1/2 pathway.