Effects of hesperetin on platelet-derived growth factor-BB-induced pulmonary artery smooth muscle cell proliferation

Proteasome inhibitor bortezomib prevents proliferation and migration of pulmonary arterial smooth muscle cells

Pulmonary vascular remodeling is a key pathological process of pulmonary arterial hypertension (PAH), characterized by uncontrolled proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs). Bortezomib (BTZ) is the first Food and Drug Administration (FDA)-approved proteasome inhibitor for multiple myeloma treatment. Recently, there is emerging evidence showing its effect on reversing PAH, although its mechanisms are not well understood. In this study, anti-proliferative and anti-migratory effects of BTZ on PASMCs were first examined by different inducers such as fetal bovine serum (FBS), angiotensin II (Ang II) and platelet-derived growth factor (PDGF)-BB, while potential mechanisms including cellular reactive oxygen species (ROS) and mitochondrial ROS were then investigated; finally, signal transduction of ERK and Akt was examined. Our results showed that BTZ attenuated FBS-, Ang II- and PDGF-BB-induced proliferation and migration, with associated decreased cellular ROS production and mitochondrial ROS production. In addition, the phosphorylation of ERK and Akt induced by Ang II and PDGF-BB was also inhibited by BTZ treatment. This study indicates that BTZ can prevent proliferation and migration of PASMCs, which are possibly mediated by decreased ROS production and down-regulation of ERK and Akt. Thus, proteasome inhibition can be a novel pharmacological target in the management of PAH.

Anti-Parkinson potential of hesperetin nanoparticles: in vivo and in silico investigations

Parkinson's disease (PD) is characterised by the gradual demise of dopaminergic neurons. In recent years, there has been significant interest in herbal treatments. In this study, hesperetin nanoparticles (HTN) were developed and compared their anti-PD potential with hesperetin (HT) on rotenone induced PD rats. Molecular docking was also performed to evaluate the binding affinity of hesperetin on pathological protein, i.e. D2 dopamine receptors (DR2), using Auto Dock Vina tools. The results showed a higher binding relationship of HTN on dopamine receptors (-7.2 kcal/mol) compared to L-dopa (-6.4 kcal/mol), supporting their potential as drug candidates for PD therapy. HTN was effectively synthesised using the fabrication technique and characterised by zeta potential and SEM analysis. HTN had favourable characteristics, including a size of 249.8 ± 14.9 nm and a Z-potential of -32.9 mV. After being administered orally, HTN demonstrated a notable anti-Parkinsonian effects, indicated by the significant improvement in motor function as assessed by the rota rod test (p < .001***), pole test (p < .001***), stair test (p < .01**), wood walk test (p < .01**) and an increase in substantia nigra (SN) antioxidant levels, CAT (p < .001***), SOD (p < .001***), GSH (p < .01**). Additionally, HTN led to increased dopamine levels (p < .01**) and a decrease in the oxidant system, MDA levels (p < .01**). Furthermore, histopathological examination revealed decreased SN neuronal necrosis in diseased animals treated with HTN compared to those treated with HT in a rat model of Parkinson's disease. Therefore, HTN can be regarded as a viable platform for efficient therapy of PD.

Traditional Chinese medicine monomers: Targeting pulmonary artery smooth muscle cells proliferation to treat pulmonary hypertension

Pulmonary hypertension (PH) is a complex multifactorial disease characterized by increased pulmonary vascular resistance and pulmonary vascular remodeling (PVR), with high morbidity, disability, and mortality. The abnormal proliferation of pulmonary artery smooth muscle cells (PASMCs) is the main pathological change causing PVR. At present, clinical treatment drugs for PH are limited, which can only improve symptoms and reduce hospitalization but cannot delay disease progression and reduce survival rate. In recent years, numerous studies have shown that traditional Chinese medicine monomers (TCMs) inhibit excessive proliferation of PASMCs resulting in alleviating PVR through multiple channels and multiple targets, which has attracted more and more attention in the treatment of PH. In this paper, the experimental evidence of inhibiting PASMCs proliferation by TCMs was summarized to provide some directions for the future development of these mentioned TCMs as anti-PH drugs in clinical.

Hesperetin ameliorates ischemia/hypoxia‐induced myocardium injury via inhibition of oxidative stress, apoptosis, and regulation of Ca 2+ homeostasis

Ischemia/hypoxia (I/H)-induced myocardial injury has a large burden worldwide. Hesperetin (HSP) has a cardioprotective effect, but the molecular mechanism underlying this is not clearly established. Here, we focused on the protective mechanisms of HSP against I/H-induced myocardium injury. H9c2 cardiomyocytes were challenged with CoCl₂ for 22 h to imitate hypoxia after treatment groups received HSP for 4 h. The viability of H9c2 cardiomyocytes was evaluated, and cardiac function indices, reactive oxygen species, apoptosis, mitochondrial membrane potential (MMP), and intracellular Ca²⁺ concentration ([Ca²⁺ ]_i ) were measured. L-type Ca²⁺ current (I_Ca-L ), myocardial contraction, and Ca²⁺ transients in isolated ventricular myocytes were also recorded. We found that HSP significantly increased the cell viability, and MMP while significantly decreasing cardiac impairment, oxidative stress, apoptosis, and [Ca²⁺ ]_i caused by CoCl₂ . Furthermore, HSP markedly attenuated I_Ca-L , myocardial contraction, and Ca²⁺ transients in a concentration-dependent manner. Our findings suggest a protective mechanism of HSP on I/H-induced myocardium injury by restoring oxidative balance, inhibiting apoptosis, improving mitochondrial function, and reducing Ca²⁺ influx via L-type Ca²⁺ channels (LTCCs). These data provide a new direction for HSP applied research as a LTCC inhibitor against I/H-induced myocardium injury.

Pulmonary arterial hypertension and flavonoids: A role in treatment

Pulmonary arterial hypertension (PAH) is a high mortality progressive pulmonary vascular disease that can lead to right heart failure. The use of clinical drugs for the treatment of PAH is limited to a great extent because of its single target and high price. Flavonoids are widely distributed in nature, and have been found in fruits, vegetables, and traditional Chinese medicine. They have diverse biological activities and various pharmacological effects such as antitumor, antioxidation, and anti-inflammatory. This review summarizes the progress in pharmacodynamics and mechanism of flavonoids in the treatment of PAH in recent years, in order to provide some theoretical references for relevant researchers.

Ameliorative Effects and Cellular Aspects of Phytoconstituents in Atherosclerosis

Atherosclerosis is a cardiovascular disease that involves vessels through the development of fatty streaks and plaques. Plant-based compounds can help treat or prevent atherosclerosis by affecting various factors that are involved in the disease. The present review discusses our current knowledge of the major cellular and molecular mechanisms of phytotherapeutics for the treatment of atherosclerosis. Numerous studies have evaluated the antiatherosclerotic activity of phytoconstituents to provide preliminary evidence of efficacy, but only a few studies have delineated the underlying molecular mechanisms. Plant-derived phytotherapeutics primarily targets abnormal levels of lipoproteins, endothelial dysfunction, smooth muscle cell migration, foam cell development, and atheromatous plaque formation. Nonetheless, the principal mechanisms that are responsible for their therapeutic actions remain unclear. Further pharmacological studies are needed to elucidate the underlying molecular mechanisms of the antiatherosclerotic response to these phytoconstituents.

Targeting Foam Cell Formation in Atherosclerosis: Therapeutic Potential of Natural Products

Foam cell formation and further accumulation in the subendothelial space of the vascular wall is a hallmark of atherosclerotic lesions. Targeting foam cell formation in the atherosclerotic lesions can be a promising approach to treat and prevent atherosclerosis. The formation of foam cells is determined by the balanced effects of three major interrelated biologic processes, including lipid uptake, cholesterol esterification, and cholesterol efflux. Natural products are a promising source for new lead structures. Multiple natural products and pharmaceutical agents can inhibit foam cell formation and thus exhibit antiatherosclerotic capacity by suppressing lipid uptake, cholesterol esterification, and/or promoting cholesterol ester hydrolysis and cholesterol efflux. This review summarizes recent findings on these three biologic processes and natural products with demonstrated potential to target such processes. Discussed also are potential future directions for studying the mechanisms of foam cell formation and the development of foam cell-targeted therapeutic strategies.

Plant-Derived Products for Treatment of Vascular Intima Hyperplasia Selectively Inhibit Vascular Smooth Muscle Cell Functions

Natural products are used widely for preventing intimal hyperplasia (IH), a common cardiovascular disease. Four different cells initiate and progress IH, namely, vascular smooth muscle, adventitial and endothelial cells, and circulation or bone marrow-derived cells. Vascular smooth muscle cells (VSMCs) play a critical role in initiation and development of intimal thickening and formation of neointimal hyperplasia. In this review, we describe the different originating cells involved in vascular IH and emphasize the effect of different natural products on inhibiting abnormal cellular functions, such as VSMC proliferation and migration. We further present a classification for the different natural products like phenols, flavonoids, terpenes, and alkaloids that suppress VSMC growth. Abnormal VSMC physiology involves disturbance in MAPKs, PI3K/AKT, JAK-STAT, FAK, and NF-κB signal pathways. Most of the natural isolate studies have revealed G1/S phase of cell cycle arrest, decreased ROS production, induced cell apoptosis, restrained migration, and downregulated collagen deposition. It is necessary to screen optimal drugs from natural sources that preferentially inhibit VSMC rather than vascular endothelial cell growth to prevent early IH, restenosis following graft implantation, and atherosclerotic diseases.

Mechanism of the effect of saikosaponin on atherosclerosis in vitro is based on the MAPK signaling pathway

The present study aimed to investigate the effects of saikosaponin on oxidized low‑density lipoprotein (ox‑LDL)‑induced human umbilical vein endothelial cell (HUVEC) injury and apoptosis, and examine the involvement of the mitogen‑activated protein kinase (MAPK) signaling pathway. The viability and apoptosis of HUVECs were detected using an MTT assay and flow cytometry. ELISA analysis was applied to measure the levels of tumor necrosis factor (TNF)‑α and interleukin (IL)‑6 cytokines. Nuclear factor (NF)‑κB p65 nuclear translocation was observed using immunofluorescence staining. The levels of intercellular adhesion molecule 1 and vascular cell adhesion molecule‑1 were detected using reverse transcription‑polymerase chain reaction analysis. The phosphorylation of B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax), caspase‑3 p38, c‑Jun N‑terminal kinase (JNK) and extracellular signal‑regulated kinase (ERK)1/2 were detected using western blot analysis. The results revealed that saikosaponin increased the viability of the HUVECs and decreased the early‑stage apoptotic rate of the HUVECs induced by ox‑LDL. The expression levels of inflammatory cytokines in the injured vascular endothelial cells were decreased, the expression levels of adhesion molecules were reduced, the activity of superoxide dismutase was increased, and malondialdehyde content was decreased. Therefore, the inflammatory response and oxidative stress were inhibited. Simultaneously, the levels of Bcl‑2 increased, the levels of Bax and caspase‑3 decreased, and the nuclear translocation of NF‑κB p65 was significantly inhibited. The protein levels of phosphorylated p38 and JNK were reduced, whereas that of ERK1/2 remained unaffected. It was concluded that the MAPK signaling pathway mediated HUVEC injury induced by ox‑LDL. However, saikosaponin inhibited the HUVEC injury induced by ox‑LDL through inhibiting the ERK1/2 and p38 MAPK signaling pathways, and possibly also through the JNK and p38 MAPK signaling pathway.