A Novel Polysaccharide From Chuanminshen violaceum and Its Protective Effect Against Myocardial Injury

Extraction, characterization and intestinal anti-inflammatory and anti-oxidative activities of polysaccharide from stems and leaves of Chuanminshen violaceum M. L. Sheh & R. H. Shan

ETHNOPHARMACOLOGICAL RELEVANCE

Chuanminshen violaceum M. L. Sheh & R. H. Shan (CV) is used as a medicine with roots, which have the effects of benefiting the lungs, harmonizing the stomach, resolving phlegm and detoxifying. Polysaccharide is one of its main active components and has various pharmacological activities, but the structural characterization and pharmacological activities of polysaccharide from the stems and leaves parts of CV are still unclear.

AIM OF THE STUDY

The aim of this study was to investigate the optimal extraction conditions for ultrasound-assisted extraction of polysaccharide from CV stems and leaves, and to carry out preliminary structural analyses, anti-inflammatory and antioxidant effects of the obtained polysaccharide and to elucidate the underlying mechanisms.

MATERIALS AND METHODS

The ultrasonic-assisted extraction of CV stems and leaves polysaccharides was carried out, and the response surface methodology (RSM) was used to optimize the extraction process to obtain CV polysaccharides (CVP) under the optimal conditions. Subsequently, we isolated and purified CVP to obtain the homogeneous polysaccharide CVP-AP-I, and evaluated the composition, molecular weight, and structural features of CVP-AP-I using a variety of technical methods. Finally, we tested the pharmacological activity of CVP-AP-Ⅰ in an LPS-induced model of oxidative stress and inflammation in intestinal porcine epithelial cells (IPEC-J2) and explored its possible mechanism of action.

RESULTS

The crude polysaccharide was obtained under optimal extraction conditions and subsequently isolated and purified to obtain CVP-AP-Ⅰ (35.34 kDa), and the structural characterization indicated that CVP-AP-Ⅰ was mainly composed of galactose, galactose, rhamnose and glucose, which was a typical pectic polysaccharide. In addition, CVP-AP-Ⅰ attenuates LPS-induced inflammation and oxidative stress by inhibiting the expression of pro-inflammatory factor genes and proteins and up-regulating the expression of antioxidant enzyme-related genes and proteins in IPEC-J2, by a mechanism related to the activation of the Nrf2/Keap1 signaling pathway.

CONCLUSION

The results of this study suggest that the polysaccharide isolated from CV stems and leaves was a pectic polysaccharide with similar pharmacological activities as CV roots, exhibiting strong anti-inflammatory and antioxidant activities, suggesting that CV stems and leaves could possess the same traditional efficacy as CV roots, which is expected to be used in the treatment of intestinal diseases.

Herbal medicines provide regulation against iron overload in cardiovascular diseases: Informing future applications

ETHNOPHARMACOLOGICAL RELEVANCE

Iron is an essential micronutrient for maintaining physiological activities, especially for highly active cardiomyocytes. Inappropriate iron overload or deficiency has a significant impact on the incidence and severity of cardiovascular diseases (CVD). Iron overload exerts potentially deleterious effects on doxorubicin (DOX) cardiomyopathy, atherosclerosis, and myocardial ischemia-reperfusion injury (MI/RI) by participating in lipid peroxides production. Notably, iron overload-associated cell death has been defined as a possible mechanism for ferroptosis. At present, some traditional herbal medicines and extracts have been included in the study of regulating iron overload and the subsequent therapeutic effect on CVD.

AIM OF THE STUDY

To give an outline of iron metabolism and ferroptosis in cardiomyocytes and to focus on herbal medicines and extracts to prevent iron overload in CVD.

MATERIALS AND METHODS

Literature information was systematically collected from ScienceDirect, PubMed, Google Scholar, Web of Science, China National Knowledge Infrastructure, WanFang data, as well as classic books and clinical reports.

RESULTS

After understanding the mechanism of iron overload on CVD, this paper reviews the therapeutic function of various herbal medicines in eliminating iron overload in CVD. These include Chinese herbal compound prescriptions (Salvia miltiorrhiza injection, Gegen Qinlian decoction, Tongxinluo, Banxia-Houpu decoction), plant extracts, phenylpropanoids, flavonoids, terpenoids, and polyphenols. Among them, flavonoids are considered to be the most promising compounds because of their prominent iron chelation. Mechanically, these herbal medicines act on the Nrf2 signaling pathway, AMPK signaling pathway, and KAT5/GPX4 signaling pathway, thereby attenuating iron overload and lipid peroxidation in CVD.

CONCLUSION

Our review provides up-to-date information on herbal medicines that exert cardiovascular protective effects by modulating iron overload and ferroptosis. These herbal medicines hold promise as a template for preventing iron overload in CVD.

The molecular mechanisms and potential drug targets of ferroptosis in myocardial ischemia-reperfusion injury

Myocardial ischemia-reperfusion injury (MIRI), caused by the initial interruption and subsequent restoration of coronary artery blood, results in further damage to cardiac function, affecting the prognosis of patients with acute myocardial infarction. Ferroptosis is an iron-dependent, superoxide-driven, non-apoptotic form of regulated cell death that is involved in the pathogenesis of MIRI. Ferroptosis is characterized by the accumulation of lipid peroxides (LOOH) and redox disequilibrium. Free iron ions can induce lipid oxidative stress as a substrate of the Fenton reaction and lipoxygenase (LOX) and participate in the inactivation of a variety of lipid antioxidants including CoQ10 and GPX4, destroying the redox balance and causing cell death. The metabolism of amino acid, iron, and lipids, including associated pathways, is considered as a specific hallmark of ferroptosis. This review systematically summarizes the latest research progress on the mechanisms of ferroptosis and discusses and analyzes the therapeutic approaches targeting ferroptosis to alleviate MIRI.

The advancement of polysaccharides in disease modulation: Multifaceted regulation of programmed cell death

Programmed cell death (PCD), also known as regulatory cell death (RCD), is a process that occurs in all organisms and is closely linked to both normal physiological processes and disease states. Various signaling pathways, such as TP53, KRAS, NOTCH, hypoxia, and metabolic reprogramming, have been found to regulate RCD. Polysaccharides, which are essential natural products, have been the subject of extensive research in the fields of food, nutrition, and medicine due to their wide range of pharmacological effects. Studies have shown that polysaccharides have biological activities and the potential to target signal transduction pathways for the treatment of diseases. This paper provides a review of the mechanisms through which polysaccharides exert their therapeutic effects at different levels and explores the relationship between different types of RCD and human diseases. The aim of this review is to provide a theoretical basis for the further clinical use and application of polysaccharide bioactivities.

The mechanism of ferroptosis and its related diseases

Ferroptosis, a regulated form of cellular death characterized by the iron-mediated accumulation of lipid peroxides, provides a novel avenue for delving into the intersection of cellular metabolism, oxidative stress, and disease pathology. We have witnessed a mounting fascination with ferroptosis, attributed to its pivotal roles across diverse physiological and pathological conditions including developmental processes, metabolic dynamics, oncogenic pathways, neurodegenerative cascades, and traumatic tissue injuries. By unraveling the intricate underpinnings of the molecular machinery, pivotal contributors, intricate signaling conduits, and regulatory networks governing ferroptosis, researchers aim to bridge the gap between the intricacies of this unique mode of cellular death and its multifaceted implications for health and disease. In light of the rapidly advancing landscape of ferroptosis research, we present a comprehensive review aiming at the extensive implications of ferroptosis in the origins and progress of human diseases. This review concludes with a careful analysis of potential treatment approaches carefully designed to either inhibit or promote ferroptosis. Additionally, we have succinctly summarized the potential therapeutic targets and compounds that hold promise in targeting ferroptosis within various diseases. This pivotal facet underscores the burgeoning possibilities for manipulating ferroptosis as a therapeutic strategy. In summary, this review enriched the insights of both investigators and practitioners, while fostering an elevated comprehension of ferroptosis and its latent translational utilities. By revealing the basic processes and investigating treatment possibilities, this review provides a crucial resource for scientists and medical practitioners, aiding in a deep understanding of ferroptosis and its effects in various disease situations.

Zooming in and out of ferroptosis in human disease

Ferroptosis is defined as an iron-dependent regulated form of cell death driven by lipid peroxidation. In the past decade, it has been implicated in the pathogenesis of various diseases that together involve almost every organ of the body, including various cancers, neurodegenerative diseases, cardiovascular diseases, lung diseases, liver diseases, kidney diseases, endocrine metabolic diseases, iron-overload-related diseases, orthopedic diseases and autoimmune diseases. Understanding the underlying molecular mechanisms of ferroptosis and its regulatory pathways could provide additional strategies for the management of these disease conditions. Indeed, there are an expanding number of studies suggesting that ferroptosis serves as a bona-fide target for the prevention and treatment of these diseases in relevant pre-clinical models. In this review, we summarize the progress in the research into ferroptosis and its regulatory mechanisms in human disease, while providing evidence in support of ferroptosis as a target for the treatment of these diseases. We also discuss our perspectives on the future directions in the targeting of ferroptosis in human disease.

The role of the ferroptosis pathway in the regulation of polysaccharides for human health: A review

Polysaccharides are natural polymers with ketone or aldehyde groups that are widely found in plants, animals, and microorganisms. They exhibit various biological activities and have potential development value in the food and pharmaceutical fields. Ferroptosis is a recently discovered modality that modulates cell death and has attracted considerable attention because it is considered to be involved in many pathophysiological processes. The inhibition of ferroptosis by reducing intracellular iron accumulation and lipid peroxidation may provide potential protective strategies against related pathologies. Ferroptosis is also involved in the physiological activities of polysaccharides, and its regulatory mechanism varies according to different physiological activities. However, a systematic summary on the involvement of ferroptosis in the physiological activities of polysaccharides is currently lacking. Therefore, this review systematically summarized the relationship between the physiological activities of polysaccharides and ferroptosis and focused on the regulatory mechanism of ferroptosis, with respect to the anti-cancer, anti-inflammatory, antioxidant, and immunomodulatory activities of all polysaccharides. The primary objective was to find new polysaccharide-related therapeutic breakthroughs for related diseases and to provide a reference for further research on polysaccharides-based therapeutics.

Electrospun Chitosan-Polyvinyl Alcohol Nanofiber Dressings Loaded with Bioactive Ursolic Acid Promoting Diabetic Wound Healing

The design and development of novel dressing materials are urgently required for the treatment of chronic wounds caused by diabetic ulcers in clinics. In this study, ursolic acid (UA) extracted from Chinese herbal plants was encapsulated into electrospun nanofibers made from a blend of chitosan (CS) and polyvinyl alcohol (PVA) to generate innovative CS-PVA-UA dressings for diabetic wound treatment. The as-prepared CS-PVA-UA nanofiber mats exhibited randomly aligned fiber morphology with the mean fiber diameters in the range of 100-200 nm, possessing great morphological resemblance to the collagen fibrils which exist in the native skin extracellular matrix (ECM). In addition, the CS-PVA-UA nanofiber mats were found to possess good surface hydrophilicity and wettability, and sustained UA release behavior. The in vitro biological tests showed that the high concentration of UA could lead to slight cytotoxicity. It was also found that the CS-PVA-UA nanofiber dressings could significantly reduce the M1 phenotypic transition of macrophages that was even stimulated by lipopolysaccharide (LPS) and could effectively restore the M2 polarization of macrophages to shorten the inflammatory period. Moreover, the appropriate introduction of UA into CS-PVA nanofibers decreased the release levels of TNF-α and IL-6 inflammatory factors, and suppressed oxidative stress responses by reducing the generation of reactive oxygen species (ROS) as well. The results from mouse hepatic hemorrhage displayed that CS-PVA-UA nanofiber dressing possessed excellent hemostatic performance. The in vivo animal experiments displayed that the CS-PVA-UA nanofiber dressing could improve the closure rate, and also promote the revascularization and re-epithelization, as well as the deposition and remodeling of collagen matrix and the regeneration of hair follicles for diabetic wounds. Specifically, the mean contraction rate of diabetic wounds using CS-PVA-UA nanofiber dressing could reach 99.8% after 18 days of treatment. In summary, our present study offers a promising nanofibrous dressing candidate with multiple biological functions, including anti-inflammation, antioxidation, pro-angiogenesis, and hemostasis functions, for the treatment of hard-to-heal diabetic wounds.