Loganin protects against myocardial ischemia-reperfusion injury by modulating oxidative stress and cellular apoptosis via activation of JAK2/STAT3 signaling

Iridoid glycosides in kidney-tonifying Chinese medicinal herbs: Mechanisms and implications for Alzheimer's disease therapy

ETHNOPHARMACOLOGICAL RELEVANCE

Alzheimer's disease (AD) is an incurable and irreversible type of dementia. Existing drugs cannot meet clinical needs; thus, developing new treatments is necessary. Traditional Chinese medicine (TCM) has been used in the prevention and treatment of AD. TCM holds the theory that "the kidney support brain function" and believes that dementia can be addressed from a kidney-based perspective. Kidney-tonifying herbs are a class of medicines that have the effect of tonifying the kidney and benefiting the brain. Some of these herbs have been shown to have anti-AD effects. Iridoid glycosides (IGs), which are important components of kidney-tonifying herbs, may have the potential to prevent and treat AD. However, their effects on AD have not yet been reviewed.

AIM OF THE REVIEW

This literature review provides a comprehensive summary of the potential of IGs in the prevention and treatment of AD. It also sets the foundation for future studies that will make the use of such drugs in clinical practice possible.

MATERIAL AND METHODS

Kidney-tonifying Chinese herbs were selected with reference to the Chinese Pharmacopoeia (2020 edition) and the textbook of Chinese Materia Medica (5th edition). Literature survey was conducted using PubMed, Web of Science, Google Scholar, and CNKI, with "Alzheimer's disease," "kidney-tonifying Chinese medicinal herbs," and "Iridoid Glycosides" as the primary keywords.

RESULTS

Kidney-tonifying herbal IGs include loganin, morroniside, verbenalin, cornuside, catalpol, rehmannioside A, geniposidic acid, and aucubin. These IGs have shown multiple pharmacological effects, including anti-AD effects. The effective mechanisms of IGs for AD treatment include anti-oxidative stress, inhibiting neuronal apoptosis, antagonizing amyloid neurotoxicity and tau protein hyperphosphorylation, regulating immune function, anti-inflammation, normalizing the function of the cholinergic nervous system, recuperating neurobiochemical, and regulating AD-related genes. Consequently, IGs can combat AD by modulating multiple targets and pathways.

CONCLUSION

Kidney-tonifying herbal IGs have great potential to combat AD.

Loganin ameliorates left ventricular fibrosis and dysfunction induced by pressure overload via the Sirt1/AKT/TGF-β1 signaling pathway

Loganin (LG), a natural compound derived from Cornus officinalis Sieb. et Zucc., possesses diverse pharmacological properties, such as anti-inflammatory, anti-hypertrophic, and antioxidant effects. However, the role of LG in the pathogenesis of Heart Failure (HF) remains unclear. The current work aimed to explore the underlying mechanism of LG in pressure overload-induced HF, both in vivo and in vitro, using transverse aortic constriction (TAC) surgery or isoproterenol (ISO) administration. Following eight weeks of TAC surgery, histological assessments, including hematoxylin and eosin staining, wheat germ agglutinin staining, TUNEL assay, and Masson's trichrome staining, were conducted to evaluate the extent of cardiomyocyte remodeling. Additionally, RT-PCR and WB analyses were performed to detect the levels of various targets. Furthermore, H9C2 cardiomyocytes were treated with ISO to induce hypertrophy, and the effects of LG on cell viability, α-smooth muscle actin (α-SMA) expression, and molecular targets were investigated. Our findings revealed that LG treatment at 40 mg/kg/day significantly attenuated cardiac dysfunction, decreased left ventricular collagen deposition in both interstitial and perivascular spaces. Mechanistically, LG mitigated ISO-induced toxicity in H9C2 cardiomyocytes, decreasing cellular hypertrophy and α-SMA expression. Moreover, we observed a downregulation of Sirtuin 1 (Sirt1) at the molecular level, accompanied by reduced phosphorylation of Akt and transforming growth factor-β1 (TGF-β1). Notably, the administration of the Sirt1 inhibitor, EX527, effectively abolished the protective effects of LG. Therefore, the cardio-protective effects of LG were mediated through the activation of the Sirt1/Akt/TGF-β1 signaling pathway, leading to reduced fibrosis and improved cardiac function.

Cigarette smoke-exposed microparticles released from T lymphocytes contribute to autophagy and apoptosis dysfunction in pulmonary microvascular endothelial cells

Cigarette smoke can cause dysfunction of the vascular endothelium; however, the underlying mechanisms have not been fully elucidated. We hypothesized that T lymphocyte-derived microparticles (TLMPs) are involved in cigarette-related diseases, especially those involving the vascular endothelium. The effect of cigarette smoke on the release of microparticles from human lymphocytes was investigated. The contributions of TLMPs induced by cigarette smoke to endothelial proliferation/apoptosis, autophagy and cytokine levels were also measured. Notably, the potential mechanism of autophagy and apoptosis dysfunction in endothelial cells was further examined. Cigarette smoke promoted the release of microparticles from T lymphocytes. TLMPs attenuated endothelial proliferation but promoted endothelial apoptosis/autophagy and the expression of proinflammatory cytokines, especially when T lymphocytes were preexposed to cigarette smoke. The potential mechanism may involve disorders of oxidative stress and STAT3 phosphorylation. In conclusion, cigarette smoke-exposed microparticles released from T lymphocytes contribute to autophagy and apoptosis dysfunction in pulmonary microvascular endothelial cells.

Shen-fu Injection Modulates HIF- 1α/BNIP3-Mediated Mitophagy to Alleviate Myocardial Ischemia-Reperfusion Injury

Coronary reperfusion therapy is the most common surgical treatment for myocardial infarction, but it can further induce myocardial ischemia-reperfusion injury (MIRI). Therefore, MIRI following coronary intervention is a challenging clinical issue. This study aims to investigate the involvement of HIF- 1α/BNIP3-mediated mitophagy in the protective effects of Shen-fu Injection (SFI) on MIRI in rats. Key targets and signaling pathways of myocardial MIRI were analyzed using high-throughput transcriptome data from the GSE240842 dataset in the GEO database.To establish the MIRI rat model, the left anterior descending coronary artery was ligated for 30 min, followed by reperfusion for 120 min. Hypoxia/reoxygenation (H/R) in neonatal rat primary cardiomyocytes was induced by oxygen-glucose deprivation for 4 h, followed by reoxygenation for 2 h. Two hours after reperfusion, assessments included myocardial infarction area, CK-MB, CTnI, HE staining, TUNEL, mitochondrial ultrastructure and autophagosomes, HIF- 1α, BNIP3, LC3B-II, LC3B-I protein expression, immunofluorescence, and qRT-PCR. Cardiac function was also evaluated using M-mode ultrasound 2 h after reperfusion. In cardiomyocytes, CCK- 8, EdU cell proliferation levels, scratch assay, mitochondrial membrane potential, ROS levels, cardiomyocyte apoptosis, protein expression levels, and immunofluorescence were assessed 2 h after reoxygenation. Our results indicate that HIF- 1α and BNIP3 are key targets in MIRI. SFI upregulates HIF- 1α expression, promoting moderate mitophagy. This process clears excessively damaged mitochondria, reduces cardiomyocyte apoptosis, and decreases myocardial injury. Additionally, SFI reduces autophagosome accumulation, lowers ROS production, and stabilizes membrane potential. Consequently, the area of myocardial infarction is reduced, and cardiac function is improved. SFI activates the HIF- 1α/BNIP3 pathway to mediate moderate mitophagy, effectively reducing cardiomyocyte apoptosis and alleviating myocardial ischemia-reperfusion injury, thereby protecting cardiomyocytes.

Platelet-mimicking nanoparticles loaded with diallyl trisulfide for Mitigating Myocardial Ischemia-Reperfusion Injury in rats

Hydrogen sulfide (H2S) shows promise in treating myocardial ischemia-reperfusion injury (MIRI), but the challenge of controlled and sustained release hinders its clinical utility. In this study, we developed a platelet membrane-encapsulated mesoporous silica nanoparticle loaded with the H2S donor diallyl trisulfide (PM-MSN-DATS). PM-MSN-DATS demonstrated optimal encapsulation efficiency and drug-loading content. Comprehensive in vitro and in vivo assessments confirmed the biosafety of PM-MSN-DATS. In vitro, PM-MSN-DATS adhered to inflammation-activated endothelial cells and exhibited targeted accumulation in MIRI rat hearts. In vivo experiments revealed significant reductions in reactive oxygen species (ROS) and myocardial fibrosis area, improving cardiac function. Our findings highlight successfully creating a targeted H2S delivery system through platelet membrane-coated MSN nanoparticles. This well-designed drug delivery platform holds significant promise for advancing MIRI treatment strategies.

Protective Effect of Carbon Dots Derived from Salvia miltiorrhiza Pretreatment in Acute Myocardial Infarction in Rats

Acute myocardial infarction is an ischemic injury of the myocardium caused by an imbalance in the blood supply to myocardial tissues, which poses a serious threat to human life and health. Oxidative stress has been recognized as a significant contributor to acute myocardial infarction. Salvia miltiorrhiza Carbonisata (SMC) is among the most frequently employed herbal remedies for the treatment of acute myocardial infarction; however, the exact identity of its principal active constituents is not well defined. Research indicates that carbon dots (CDs) exhibit significant biological properties. Consequently, we initially synthesized carbon dots (CDs) from Salvia miltiorrhiza Carbonisata, with the objective of exploring how SMC-CDs mitigate isoproterenol (ISO)-induced myocardial infarction (MI) in rats. The results showed that the pretreatment with SMC-CDs markedly enhanced compromised cardiac function, mitigated myocardial fibrosis and the infiltration of inflammatory cells, decreased the size of the infarct, and suppressed cardiomyocyte apoptosis. Furthermore, the antioxidant properties of myocardial tissue were enhanced, and oxidative stress caused by free radicals was effectively mitigated by SMC-CDs, which succeeded in reducing levels of myocardial enzymes and elevating the activity of relevant ATPases. This implies that SMC-CDs could be a potential candidate for novel nanomedicine strategies designed to address cardiovascular ailments.

Loganin attenuates the inflammation, oxidative stress, and apoptosis through the JAK2/STAT3 pathway in cerebral ischemia-reperfusion injury

BACKGROUND

Loganin, a monoterpene iridoid glycoside derived from Cornus officinalis Sieb. Et Zucc, has been reported to have anti-inflammatory and antioxidant activity. Nevertheless, the potential role and molecular mechanism of loganin in cerebral ischemia-reperfusion (I/R) injury are not well-understood. The purpose of the study was to explore the functional role of loganin in the inflammation, oxidative stress, and apoptosis in cerebral I/R injury in rats MATERIALS AND METHODS: Following middle cerebral artery occlusion (MCAO), 80 mg/kg of loganin was intragastrically administered for 7 consecutive days. Neuromotor function scores were performed 24 h after the last administration, and the cerebral infarction volume was determined by TTC straining. The expressions of IL-6, IL-1β, and TNF-α in the brain tissues of MCAO rats were detected by ELISA assay. The activities of ROS, SOD, and MDA were measured by ELISA assay as well. Cell apoptosis were was tested by TUNEL straining. Western blot assay was applied for measuring the protein levels RESULTS: We observed that the expressions of IL-6, IL-1β, and TNF-α were amplitude markedly elevated in the rats following MCAO. Treatment with loganin obviously reduced these expressions in the brain tissues of MCAO rats. ELISA assay showed that ROS generation and MDA activity were increased in MCAO group and it was decreased after treatment with loganin. However, loganin increased the SOD activity, which was reduced by MCAO operation. Moreover, loganin promoted neurological function improvement and inhibited cell apoptosis in the rats after MCAO. Mechanically, loganin triggered JAK2/STAT3 phosphorylation in the rats following MCAO, and activation of JAK2/STAT3 pathway rescued the inhibition effects of loganin on the inflammation, oxidative stress, and apoptosis CONCLUSIONS: These results provide evidence that loganin may alleviate the inflammation, oxidative stress, and apoptosis through the JAK2/STAT3 pathway in MCAO rats.

GDF15 attenuates sepsis-induced myocardial dysfunction by inhibiting cardiomyocytes ferroptosis via the SOCS1/GPX4 signaling pathway

Sepsis is a systemic inflammatory response syndrome triggered by infection, presenting with symptoms such as fever, increased heart rate, and low blood pressure. In severe cases, it can lead to multiple organ dysfunction, posing a life-threatening risk. Sepsis-induced cardiomyopathy (SIC) is a critical factor in the poor prognosis of septic patients, leading to myocardial dysfunction characterized by cell death, inflammation, and diminished cardiac function. Ferroptosis, an iron-dependent form of programmed cell death, is a key mechanism causing cardiomyocyte damage in SIC. Growth differentiation factor 15 (GDF15), a member of the TGF-β superfamily, is associated with various cardiovascular diseases and can inhibit oxidative stress, reduce reactive oxygen species (ROS), and suppress ferroptosis. Elevated serum GDF15 levels in sepsis are correlated with organ injuries, suggesting its potential as a therapeutic target. However, its role and mechanisms in SIC remain unclear. Glutathione peroxidase 4 (GPX4), the only enzyme capable of reducing lipid peroxides within cells, protects cells by reducing lipid peroxidation levels and inhibiting ferroptosis. Investigating the regulatory factors of GPX4 may provide a theoretical basis for SIC treatment. In this study, a mouse SIC model revealed that elevated GDF15 exerts a protective effect. Antagonizing GDF15 exacerbates myocardial damage. Through transcriptomic analysis and other methods, we confirmed that GDF15 inhibits the expression of SOCS1 by activating the ALK5-SMAD2/3 pathway, thereby activates the JAK2/STAT3 pathway, promotes the transcription of GPX4, inhibits ferroptosis in cardiomyocytes, and plays a myocardial protective role in SIC.

Verapamil attenuates myocardial ischemia/reperfusion injury by inhibiting apoptosis via activating the JAK2/STAT3 signaling pathway

Apoptosis is a crucial pathological process in myocardial ischemia/reperfusion injury (MIRI). Verapamil (Ver), normally used to treat hypertension or heart rhythm disorders, also attenuates MIRI. The potential of Ver to inhibit apoptosis and thereby attenuate MIRI remains unclear, as does the mechanism. We established an in vivo mouse ischemia/reperfusion (I/R) model by occlusion of the left anterior descending coronary. To construct a hypoxia/reoxygenation model in vitro, H9c2 cardiomyocytes were immersed in a hypoxic buffer in a hypoxia/anaerobic workstation. Ver significantly improved cardiac function and reduced myocardial infarction size in I/R mice, while decreasing apoptosis. Both in vivo and in vitro, application of Ver activated the JAK2/STAT3 signaling pathway and elevated Bcl-2 expression, while decreasing Bax and cleaved caspase-3 levels. Treatment with AG490, a JAK2 inhibitor, partially counteracted the anti-apoptotic and the cardioprotective effect of Ver. Thus, we conclude that Ver alleviates MIRI by reducing apoptosis via the JAK2/STAT3 signaling pathway activation. These findings provide a novel mechanism of Ver in the treatment of MIRI.

An RGD-Conjugated Prodrug Nanoparticle with Blood-Brain-Barrier Penetrability for Neuroprotection Against Cerebral Ischemia-Reperfusion Injury

Cerebral ischemia-reperfusion injury significantly contributes to global morbidity and mortality. Loganin is a natural product with various neuroprotective effects; however, it lacks targeted specificity for particular cells or receptors, which may result in reduced therapeutic efficacy and an increased risk of side effects. To address the limitations of loganin, we developed LA-1, a novel compound incorporating an Arg-Gly-Asp (RGD) peptide to target integrin receptor αvβ3, enhancing brain-targeting efficacy. LA-1 exhibited optimal nanoscale properties, significantly improved cell viability, reduced ROS production, and enhanced survival rates in vitro. In vivo, LA-1 decreased infarct sizes, improved neurological function, and reduced oxidative stress and neuroinflammation. Proteomic analysis showed LA-1 modulates PI3K/Akt and Nrf2/HO-1 pathways, providing targeted neuroprotection. These findings suggest LA-1's potential for clinical applications in treating cerebral ischemia-reperfusion injury.

Oxidative Stress and Inflammation in Myocardial Ischemia-Reperfusion Injury: Protective Effects of Plant-Derived Natural Active Compounds

Acute myocardial infarction (AMI) remains a leading cause of death among patients with cardiovascular diseases. Percutaneous coronary intervention (PCI) has been the preferred clinical treatment for AMI due to its safety and efficiency. However, research indicates that the rapid restoration of myocardial oxygen supply following PCI can lead to secondary myocardial injury, termed myocardial ischemia-reperfusion injury (MIRI), posing a grave threat to patient survival. Despite ongoing efforts, the mechanisms underlying MIRI are not yet fully elucidated. Among them, oxidative stress and inflammation stand out as critical pathophysiological mechanisms, playing significant roles in MIRI. Natural compounds have shown strong clinical therapeutic potential due to their high efficacy, availability, and low side effects. Many current studies indicate that natural compounds can mitigate MIRI by reducing oxidative stress and inflammatory responses. Therefore, this paper reviews the mechanisms of oxidative stress and inflammation during MIRI and the role of natural compounds in intervening in these processes, aiming to provide a basis and reference for future research and development of drugs for treating MIRI.

A single-chain antibody construct with specificity of a natural IgM antibody reduces hepatic ischemia reperfusion injury in mice

Natural immunoglobulin M (IgM) antibodies have been shown to recognize post-ischemic neoepitopes following reperfusion of tissues and to activate complement. Specifically, IgM antibodies and complement have been shown to drive hepatic ischemia reperfusion injury (IRI). Herein, we investigate the therapeutic effect of C2 scFv (single-chain antibody construct with specificity of a natural IgM antibody) on hepatic IRI in C57BL/6 mice. Compared with PBS-treated mice, C2 scFv-treated mice displayed almost no necrotic areas, significant reduction in serum ALT, AST and LDH levels, and significantly reduced in the number of TUNEL positive cells. Moreover, C2 scFv-treated mice exhibited a notable reduction in inflammatory cells after hepatic IRI than PBS-treated mice. The serum IL-6, IL-1β, TNF-α and MPC-1 levels were also severely suppressed by C2 scFv. Interestingly, C2 scFv reconstituted hepatic inflammation and IRI in Rag1-/- mice. We found that C2 scFv promoted hepatic cell death and increased inflammatory cytokines and infiltration of inflammatory cells after hepatic IRI in Rag1-/- mice. In addition, IgM and complement 3d (C3d) were deposited in WT mice and in Rag1-/- mice reconstituted with C2 scFv, indicating that C2 scFv can affect IgM binding and complement activation and reconstitute hepatic IRI. C3d expression was significantly lower in C57BL/6 mice treated with C2 scFv compared to PBS, indicating that excessive exogenous C2 scFv inhibited complement activation. These data suggest that C2 scFv alleviates hepatic IRI by blocking complement activation, and treatment with C2 scFv may be a promising therapy for hepatic IRI.

Targeting the JAK2/STAT3 signaling pathway with natural plants and phytochemical ingredients: A novel therapeutic method for combatting cardiovascular diseases

The aim of this article is to introduce the roles and mechanisms of the JAK2/STAT3 pathway in various cardiovascular diseases, such as myocardial fibrosis, cardiac hypertrophy, atherosclerosis, myocardial infarction, and myocardial ischemiareperfusion. In addition, the effects of phytochemical ingredients and different natural plants, mainly traditional Chinese medicines, on the regulation of different cardiovascular diseases via the JAK2/STAT3 pathway are discussed. Surprisingly, the JAK2 pathway has dual roles in different cardiovascular diseases. Future research should focus on the dual regulatory effects of different phytochemical ingredients and natural plants on JAK2 to pave the way for their use in clinical trials.