Terminalia arjuna prevents Interleukin-18-induced atherosclerosis via modulation of NF-κB/PPAR-γ-mediated pathway in Apo E-/- mice

Black phosphorus quantum dots induce myocardial inflammatory responses and metabolic disorders in mice

As an ultrasmall derivative of black phosphorus (BP) sheets, BP quantum dots (BP-QDs) have been effectively used in many fields. Currently, information on the cardiotoxicity induced by BP-QDs remains limited. We aimed to evaluate BP-QD-induced cardiac toxicity in mice. Histopathological examination of heart tissue sections was performed. Transcriptome sequencing, real-time quantitative PCR (RT‒qPCR), western blotting, and enzyme-linked immunosorbent assay (ELISA) assays were used to detect the mRNA and/or protein expression of proinflammatory cytokines, nuclear factor kappa B (NF-κB), phosphatidylinositol 3 kinase-protein kinase B (PI3K-AKT), peroxisome proliferator-activated receptor gamma (PPARγ), and glucose/lipid metabolism pathway-related genes. We found that heart weight and heart/body weight index (HBI) were significantly reduced in mice after intragastric administration of 0.1 or 1 mg/kg BP-QDs for 28 days. In addition, obvious inflammatory cell infiltration and increased cardiomyocyte diameter were observed in the BP-QD-treated groups. Altered expression of proinflammatory cytokines and genes related to the NF-κB signaling pathway further confirmed that BP-QD exposure induced inflammatory responses. In addition, BP-QD treatment also affected the PI3K-AKT, PPARγ, thermogenesis, oxidative phosphorylation, and cardiac muscle contraction signaling pathways. The expression of genes related to glucose/lipid metabolism signaling pathways was dramatically affected by BP-QD exposure, and the effect was primarily mediated by the PPAR signaling pathway. Our study provides new insights into the toxicity of BP-QDs to human health.

Terminalia arjuna, a Cardioprotective Herbal Medicine-Relevancy in the Modern Era of Pharmaceuticals and Green Nanomedicine-A Review

Herbal medicines were the main source of therapeutic agents in the ancestral era. Terminalia arjuna (TA) is one such medicinal plant widely known for its several medicinal properties, especially its cardiovascular properties. They have several phytochemicals, such as flavonoids, polyphenols, triterpenoids, tannins, glycosides, and several minerals, proteins, and others that are responsible for the above-mentioned medicinal properties. In this review, we have first elaborated on the various processes and their parameters for the efficient extraction of relevant phytochemicals from TA extracts. Secondly, the mechanisms behind the various medicinal properties of TA extracts are explained. We have also highlighted the role of TA extracts on the green synthesis of metallic nanoparticles, especially silver and gold nanoparticles, with an elucidation on the mechanisms behind the synthesis of nanoparticles. Finally, TA extracts-based polymeric formulations are discussed with limitations and future perspectives. We believe that this review could help researchers understand the importance of a well-known cardioprotective medicinal plant, TA, and its biomedical properties, as well as their role in green nanotechnology and various formulations explored for encapsulating them. This review will help researchers design better and greener nanomedicines as well as better formulations to improve the stability and bioavailability of TA extracts.

The IL-1 Family and Its Role in Atherosclerosis

The IL-1 superfamily of cytokines is a central regulator of immunity and inflammation. The family is composed of 11 cytokines (with agonist, antagonist, and anti-inflammatory properties) and 10 receptors, all tightly regulated through decoy receptor, receptor antagonists, and signaling inhibitors. Inflammation not only is an important physiological response against infection and injury but also plays a central role in atherosclerosis development. Several clinical association studies along with experimental studies have implicated the IL-1 superfamily of cytokines and its receptors in the pathogenesis of cardiovascular disease. Here, we summarize the key features of the IL-1 family, its role in immunity and disease, and how it helps shape the development of atherosclerosis.

Isolation of two new triterpene glycoside from the fruits of Terminalia arjuna and their in vitro and in silico studies

Two new triterpene glycoside, Arjunoglycoside VI (1) and Arjunursglycoside I (2) alone with five previously known analogues (3-7) were isolated from methanolic extract of the fruits of Terminalia arjuna. The structures were elucidated by extensive spectroscopic studies (1 D and 2 D NMR and mass). Compound 1 and 2 showed moderate activity on α-chymotrypsin enzyme inhibition with IC₅₀ values 53.8 ± 1.39 and 64.27 ± 1.27 µg/mL respectively. Molecular docking was performed for compound 1 and 2 with the 1CGI co crystals of α-chymotrypsin enzyme protein of Bovine from protein data bank showed -7.7 and -7.6 kcal/mol binding energy, respectively.

HomeoboxC6 affects the apoptosis of human vascular endothelial cells and is involved in atherosclerosis

Apoptosis of vascular endothelial cells (VECs) is highly important in the occurrence and development of atherosclerosis (AS). HomeboxC6 (HOXC6) is expressed in higher levels in multiple malignant tissues, and it influences the malignant biological behavior of the cancer cells. However, the effects of HOXC6 on AS and the apoptosis of VECs have not been fully elucidated. In this study, we demonstrated that HOXC6 expression was increased in aortic wall of AS rats and peripheral blood monocytes of patients with coronary heart disease. Furthermore, it was uncovered that BAX expression was upregulated, while BCL-2 expression was downregulated in the aortic wall of AS rats. The apoptosis of human VECs (HVECs) cultured normally or treated with oxidized low-density lipoprotein in vitro was decreased after transfection with HOXC6-siRNA. Moreover, the results of Western blot analysis unveiled that the expressions of proapoptotic proteins, such as BAX, caspase-3, cleaved-caspase-3, and caspase-9 were reduced, while the expression of antiapoptotic protein, BCL-2, was elevated. Meanwhile, mRNA and protein expressions of phospholipase C beta (PLCβ) were decreased, the phosphorylation levels of protein kinase C zeta (PKCζ) and nuclear transcription factor-κB-p65 (NF-κBp65) and the membrane translocation of PKCζ were reduced as well. Besides, the expression of interleukin-18 (IL-18) protein was downregulated. However, after overexpression of HOXC6, the opposite trends of the abovementioned indices were observed. Furthermore, the inhibition of apoptosis induced by HOXC6-siRNA was reversed by lysophosphatidylcholine, an activator of PKCζ. Taken together, our results indicated that HOXC6 can promote the apoptosis of HVECs and may be involved in the occurrence and development of AS, which may be partially associated with the activation of PLCβ/PKCζ/NF-κBp65/IL-18 signaling pathway.

Danlou tablet inhibits the inflammatory reaction of high-fat diet-induced atherosclerosis in ApoE knockout mice with myocardial ischemia via the NF-κB signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Danlou tablet (DLT), a traditional herbal formula, has been used to treat chest discomfort (coronary atherosclerosis) in China. Although the anti-inflammatory activities of DLT have been proposed previously, the mechanisms of DLT in treating atherosclerosis with myocardial ischemia (AWMI) remain unknown.

AIM OF THE STUDY

Atherosclerosis can result in heart disease caused by stenosis or occlusion of the lumen, resulting in myocardial ischemia, hypoxia, or necrosis. In recent years, changes in people's diets, increased stress, and secondary fatigue and obesity etc. have resulted in increases in the number of patients with atherosclerosis. In cases where the condition has further developed, patients may suffer from myocardial ischemia, hypoxia, or necrosis. Many traditional Chinese medicine compounds have been prescribed for the treatment of AWMI. DLT has been used to treat chest discomfort (coronary atherosclerosis) in China. Based on previous research, the aim of this study was to further investigate the effect of DLT on AWMI, and describe the underlying mechanisms.

MATERIALS AND METHODS

To achieve this, an animal model of AWMI was established using apolipoprotein E (ApoE^-/-) mice fed a high fat diet combined with isoprenaline (ISO) injection. For comparison, mouse models of only atherosclerosis and only myocardial ischemia were included. In the treatment groups, mice were treated daily with DLT at 700 mg/kg for four weeks. Echocardiographic evaluation, hematoxylin and eosin (H&E) staining, oil red O staining, ELISAs, Western blots, and immunohistochemical analyses were subsequently used to investigate the mechanism of DLT based on the NF-κB signaling pathway.

RESULTS

The results indicate that the use of DLT is effective, to varying degrees, for the treatment of atherosclerosis, myocardial ischemia, and AWMI in mice. After DLT treatment, the left ventricular structure and morphology of the mice, the histopathology of cardiac tissue, and atherosclerotic plaques in the aortas all improved to varying degrees. DLT could play a therapeutic role by regulating the NF-κB signaling pathway related to inflammatory factors, including TNF-α, IL-6, IL-1β, IL-8, MMP-1 and MMP-2, as well as protein expression of NF-κB p-50 and IκB-α, and positive cell expression of NF-κB p-50, IκB-α and phospho-NF-κB p-50 in the model mice.

CONCLUSION

These preliminary results indicate that the therapeutic efficacy of DLT on high-fat diet-induced atherosclerosis in ApoE^-/- mice with myocardial ischemia could be exerted at least in part by regulating the NF-κB signaling pathway.

Involvement of the toll-like receptors-2/nuclear factor-kappa B signaling pathway in atherosclerosis induced by high-fat diet and zymosan A in C57BL/6 mice

OBJECTIVE:

Accumulated evidence reported a link between the immune system, microbial infection, and the development of atherosclerosis. Excess intake of high-fat diet (HFD) increases blood lipid levels and induces inflammatory pathways whereas zymosan A (Zym), a microbial component, mediates inflammatory response through the stimulation of specific ligand of toll-like receptors (TLRs) of the immune system. The current research work was aimed to evaluate the mechanism behind atherosclerosis mediated by HFD and Zym in C57BL/6 mice.

MATERIALS AND METHODS:

The mice were orally fed with HFD for 30 days and Zym (80 mg/kg, single intraperitoneal injection on day 8^th). On the 31^st day, blood was withdrawn from overnight fasted mice by tail vein puncture and estimated for serum lipids and tumor necrosis factor-alpha (TNF-α). Animals were sacrificed, and cardiac, liver, and aortic tissues were isolated for the estimation of cardiac TLR-2, nuclear factor-kappa B (NF-ƙB); hepatic low-density lipoprotein receptors (LDLR); and base of aorta analyzed for histopathology.

RESULTS:

It was found that HFD and Zym administration increased arterial inflammation directly through modulation of the TLR-2/NF-ƙB pathway, thereby upregulate serum TNF-α, cardiac TLR-2, and NF-ƙB levels. Further, HFD and Zym treatment significantly increased serum lipid levels and marked decrease in LDLR protein expression in the liver when compared to normal control mice. Histopathological analysis showed the formation of atherosclerotic plaque.

CONCLUSION:

The study is first, to our current knowledge, to demonstrate the involvement of the TLR-2/NF-ƙB signaling pathway in atherosclerosis induced by HFD and Zym in C57BL/6 mice, resulting in increased degradation of LDLR protein, thereby, increasing the serum lipid levels.

Therapeutic potential of PPARγ natural agonists in liver diseases

Peroxisome proliferator‐activated receptor gamma (PPARγ) is a vital subtype of the PPAR family. The biological functions are complex and diverse. PPARγ plays a significant role in protecting the liver from inflammation, oxidation, fibrosis, fatty liver and tumours. Natural products are a promising pool for drug discovery, and enormous research effort has been invested in exploring the PPARγ‐activating potential of natural products. In this manuscript, we will review the research progress of PPARγ agonists from natural products in recent years and probe into the application potential and prospects of PPARγ natural agonists in the therapy of various liver diseases, including inflammation, hepatic fibrosis, non‐alcoholic fatty liver and liver cancer.

Comparative Evaluation of Conventional and Novel Extracts of Stem Bark of Terminalia arjuna for Antihypertensive Activity in BSO Induced Oxidative Stress based Rat Model

BACKGROUND

Terminalia arjuna (TA) has been reported and explored traditionally for its cardiotonic properties while the mechanism of antihypertensive effect of TA has not been clearly reported.

METHOD

The oxidative stress is a major cause for hypertension, hence different extracts of TA having variable marker yield were evaluated for their antihypertensive effect in buthionine sulfoxamine (BSO) induced oxidative stress based model. Soxhlet extraction (SE), room temperature extraction (RTE), microwave assisted extraction (MAE), and ultrasound assisted extraction (USAE) were quantitatively estimated for marker compounds arjunolic acid and arjunic acid through HPTLC.

RESULTS

The hypertension was induced using buthionine sulfoxamine (2 mmol/kg b.w. i.p.) and results suggested that the MAE and USAE showed better recovery of systolic blood pressure (110.33±0.10 and 118.33±0.10) and GSH level (3.62±0.07 nmoles/mL and 3.22±0.13 nmoles/mL), respectively as compared to the positive control group treated with ascorbic acid (Systolic BP: 119.67±0.10, GSH level: 3.11±0.10 nmoles/mL). The RTE and SE also showed a decrease in hypertension but were having moderate effect as compared with the standard positive control.

CONCLUSION

The total percentage yield, the yield of the marker compounds arjunolic and arjunic acid, the IC50 values for antioxidant activity as well as the antihypertensive effect were in order: MAE>USAE>SE>RTE that suggested the role of biomarkers arjunolic acid and arjunic acid in reversing the effect of buthionine sulfoxamine.

Isoproterenol-induced cardiac ischemia and fibrosis: Plant-based approaches for intervention

Heart is the most active and incumbent organ of the body, which maintains blood flow, but due to various pathological reasons, several acute and chronic cardiac complications arise out of which myocardial infarction is one of the teething problems. Isoproterenol (ISP)-induced myocardial ischemia is a classical model to screen the cardioprotective effects of various pharmacological interventions. Phytochemicals present a novel option for treating various human maladies including those of the heart. A large number of plant products and their active ingredients have been screened for efficacy in ameliorating ISP-induced myocardial ischemia including coriander, curcumin, Momordica, quercetin, and Withania somnifera. These phytochemicals constituents may play key role in preventing disease and help in cardiac remodeling. Reactive oxygen species scavenging, antiinflammatory, and modulation of various molecular pathways such as Nrf2, NFкB, p-21 activated kinase 1 (PAK1), and p-smad2/3 signaling modulation have been implicated behind the claimed protection. In this review, we have provided a focused overview on the utility of ISP-induced cardiotoxicity, myocardial ischemia, and cardiac fibrosis for preclinical research. In addition, we have also surveyed molecular mechanism of various plant-based interventions screened for cardioprotective effect in ISP-induced cardiotoxicity, and their probable mechanistic profile is summarized.