Hydrogels for the Treatment of Myocardial Infarction: Design and Therapeutic Strategies

Enhanced electrochemical aptasensor integrating MoS2/CuS-Au and SI-RAFT for dual signal amplification in cTnI detection

Cardiac troponin I (cTnI) is known to be among the prominent diagnostic bio-marker for acute myocardial infarction (AMI). In this paper, we proposed an electrochemical aptasensor with nanomaterial MoS2/CuS-Au as the substrate material and perillaldehyde (PA) as the surface-initiated reversible addition fragmentation chain transfer (SI-RAFT) polymerization monomer by mediating the in-situ deposition of silver metal on the electrode surface for ultrasensitive detection of cTnI. The substrate material MoS2/CuS-Au not only accelerated the rate transfer between electron, but also provided more active sites for aptamers introduction. The perillaldehyde (PA) monomers were modified onto the electrode by surface-initiated reversible addition fragmentation chain transfer polymerization (SI-RAFT), and the signal was amplified in one step by reducing silver ions to metallic silver deposited in situ on the upper of the electrode surface. Under optimum reaction conditions, this aptasensor achieved a detection limit down to 10.83 fg·mL-1. The proposed aptasensor without additional natural enzymes or biological tags, had a promising potential for use in the diagnosis of early acute myocardial infarction (AMI).

Shear-Thinning Hydrogel for Delayed Delivery of a Small Molecule Metalloproteinase Inhibitor Attenuates Myocardial Infarction Remodeling

Strategic delivery of hydrogels to the newly formed myocardial infarction (MI) is an area of active investigation and offers high target specificity for releasing a small molecule therapeutic payload. This study examined the effects of delayed post-MI delivery (pigs, 3 days post-MI) of a shear-thinning hydrogel which encapsulated and released a small molecule matrix metalloproteinase inhibitor. The results demonstrated the feasibility and efficacy of targeted delivery of a shear-thinning injectable hydrogel containing a small molecule matrix metalloproteinase inhibitor to attenuate post-MI remodeling.

Adhesive and Conductive Hydrogels for the Treatment of Myocardial Infarction

Myocardial infarction (MI) is a leading cause of mortality among cardiovascular diseases. Following MI, the damaged myocardium is progressively being replaced by fibrous scar tissue, which exhibits poor electrical conductivity, ultimately resulting in arrhythmias and adverse cardiac remodeling. Due to their extracellular matrix-like structure and excellent biocompatibility, hydrogels are emerging as a focal point in cardiac tissue engineering. However, traditional hydrogels lack the necessary conductivity to restore electrical signal transmission in the infarcted regions. Imparting conductivity to hydrogels while also enhancing their adhesive properties enables them to adhere closely to myocardial tissue, establish stable electrical connections, and facilitate synchronized contraction and myocardial tissue repair within the infarcted area. This paper reviews the strategies for constructing conductive and adhesive hydrogels, focusing on their application in MI repair. Furthermore, the challenges and future directions in developing adhesive and conductive hydrogels for MI repair are discussed.

Inflammatory Cell-Targeted Delivery Systems for Myocardial Infarction Treatment

Myocardial infarction (MI) is a cardiovascular disease (CVD) with high morbidity and mortality worldwide, which is a serious threat to human life and health. Inflammatory and immune responses are initiated immediately after MI, and unbalanced inflammation post-MI can lead to cardiac dysfunction, scarring, and ventricular remodeling, emphasizing the critical need for an effective inflammation-regulating treatment. With the development of novel therapies, the drug delivery system specific to inflammatory cells offers significant potential. In this review, we introduce immune cells and fibroblasts involved in the development of MI and summarize the newly developed delivery systems related to the use of injectable hydrogels, cardiac patches, nanoparticles, and extracellular vesicles (EVs). Finally, we highlight the recent trends in the use of inflammatory cell-targeting drug delivery systems involving different strategies that facilitate the effective treatment of MI.

Curving-Stretching Induced Alignment in Hydrogel Actuators for Enhanced Grip Strength and Rapid Response

Natural tissues, like ligaments and tendons, display not just robust mechanical performance but also complex anisotropic structures extending beyond one-directional arrangements. However, fabricating hydrogel actuators with biomimetic three-dimensional anisotropy remains challenging. Herein, a simple strategy involving curving-stretching induced alignment is proposed to prepare anisotropic Fe3+-cross-linked poly(acrylic acid)-poly(acrylamide) hydrogel actuators. These hydrogels exhibit exceptional mechanical properties, boasting a fracture stress of 7.1 MPa and a superior modulus of 33.2 MPa when prestretched to 200% strain, which are 2.3 times and 4.9 times higher than their unstretched counterparts. The stretched anisotropic hydrogel gripper, stronger than its unstretched counterpart, can lift heavy objects while also achieving rapid responsiveness to stimuli. This work introduces a novel and effective method for fabricating anisotropic hydrogels, highlighting their broad applicability in fields such as soft robotics, biomedical devices, and beyond.

Advances in Functionalized Hydrogels in the Treatment of Myocardial Infarction and Drug-Delivery Strategies

Myocardial infarction (MI) is a serious cardiovascular disease with high morbidity and mortality rates, posing a significant threat to patient's health and quality of life. Following a MI, the damaged myocardial tissue is typically not fully repaired, leading to permanent impairment of myocardial function. While traditional treatments can alleviate symptoms and reduce pain, their ability to repair damaged heart muscle tissue is limited. Functionalized hydrogels, a broad category of materials with diverse functionalities, can enhance the properties of hydrogels to cater to the needs of tissue engineering, drug delivery, medical dressings, and other applications. Recently, functionalized hydrogels have emerged as a promising new therapeutic approach for the treatment of MI. Functionalized hydrogels possess outstanding biocompatibility, customizable mechanical properties, and drug-release capabilities. These properties enable them to offer scaffold support, drug release, and tissue regeneration promotion, making them a promising approach for treating MI. This paper aims to evaluate the advancements and delivery methods of functionalized hydrogels for treating MI, while also discussing their potential and the challenges they may pose for future clinical use.

Navigating the landscape of RNA delivery systems in cardiovascular disease therapeutics

Cardiovascular diseases (CVDs) stand as the leading cause of death worldwide, posing a significant global health challenge. Consequently, the development of innovative therapeutic strategies to enhance CVDs treatment is imperative. RNA-based therapies, encompassing non-coding RNAs, mRNA, aptamers, and CRISPR/Cas9 technology, have emerged as promising tools for addressing CVDs. However, inherent challenges associated with RNA, such as poor cellular uptake, susceptibility to RNase degradation, and capture by the reticuloendothelial system, underscore the necessity of combining these therapies with effective drug delivery systems. Various non-viral delivery systems, including extracellular vesicles, lipid-based carriers, polymeric and inorganic nanoparticles, as well as hydrogels, have shown promise in enhancing the efficacy of RNA therapeutics. In this review, we offer an overview of the most relevant RNA-based therapeutic strategies explored for addressing CVDs and emphasize the pivotal role of delivery systems in augmenting their effectiveness. Additionally, we discuss the current status of these therapies and the challenges that hinder their clinical translation.