Protective effects of salvianolic acid B against hydrogen peroxide‑induced apoptosis of human umbilical vein endothelial cells and underlying mechanisms

Salvianolic Acid B Alleviates High Glucose-Induced Vascular Smooth Muscle Cell Inflammation by Upregulating the miR-486a-5p Expression

The macrovascular complications of diabetes cause high mortality and disability in patients with type 2 diabetes mellitus (T2DM). The inflammatory response of vascular smooth muscle cell (VSMC) runs through its pathophysiological process. Salvianolic acid B (Sal B) exhibits beneficial effects on the cardiovascular system. However, its role and mechanism in diabetic vascular inflammatory response remain unclear. In this study, we found that Sal B reduced vascular inflammation in diabetic mice and high glucose- (HG-) induced VSMC inflammation. Subsequently, we found that Sal B reduced HG-induced VSMC inflammation by downregulating FOXO1. Furthermore, miR-486a-5p expression was obviously reduced in HG-treated VSMC. Sal B attenuated HG-induced VSMC inflammation by upregulating miR-486a-5p. Loss- and gain-of-function experiments had proven that the transfection of the miR-486a-5p mimic inhibited HG-induced VSMC inflammation whereas that of the miR-486a-5p inhibitor promoted HG-induced VSMC inflammation, thereby leading to the amelioration of vascular inflammation in the diabetic mice. Furthermore, studies had shown that miR-486a-5p inhibited FOXO1 expression by directly targeting its 3'-UTR. In conclusion, Sal B alleviates the inflammatory response of VSMC by upregulating miR-486a-5p and aggravating its inhibition of FOXO1 expression. Sal B exerts a significant anti-inflammatory effect in HG-induced VSMC inflammation by modulating the miR-486a-5p/FOXO1 axis.

Physiological and pathological characteristics of vascular endothelial injury in diabetes and the regulatory mechanism of autophagy

Vascular endothelial injury in diabetes mellitus (DM) is the major cause of vascular disease, which is closely related to the occurrence and development of a series of vascular complications and has a serious negative impact on a patient's health and quality of life. The primary function of normal vascular endothelium is to function as a barrier function. However, in the presence of DM, glucose and lipid metabolism disorders, insulin resistance, inflammatory reactions, oxidative stress, and other factors cause vascular endothelial injury, leading to vascular endothelial lesions from morphology to function. Recently, numerous studies have found that autophagy plays a vital role in regulating the progression of vascular endothelial injury. Therefore, this article compares the morphology and function of normal and diabetic vascular endothelium and focuses on the current regulatory mechanisms and the important role of autophagy in diabetic vascular endothelial injury caused by different signal pathways. We aim to provide some references for future research on the mechanism of vascular endothelial injury in DM, investigate autophagy's protective or injurious effect, and study potential drugs using autophagy as a target.

Natural compounds from botanical drugs targeting mTOR signaling pathway as promising therapeutics for atherosclerosis: A review

Atherosclerosis (AS) is a chronic inflammatory disease that is a major cause of cardiovascular diseases (CVDs), including coronary artery disease, hypertension, myocardial infarction, and heart failure. Hence, the mechanisms of AS are still being explored. A growing compendium of evidence supports that the activity of the mechanistic/mammalian target of rapamycin (mTOR) is highly correlated with the risk of AS. The mTOR signaling pathway contributes to AS progression by regulating autophagy, cell senescence, immune response, and lipid metabolism. Various botanical drugs and their functional compounds have been found to exert anti- AS effects by modulating the activity of the mTOR signaling pathway. In this review, we summarize the pathogenesis of AS based on the mTOR signaling pathway from the aspects of immune response, autophagy, cell senescence, and lipid metabolism, and comb the recent advances in natural compounds from botanical drugs to inhibit the mTOR signaling pathway and delay AS development. This review will provide a new perspective on the mechanisms and precision treatments of AS.

Salvianolic acid B combined with bone marrow mesenchymal stem cells piggybacked on HAMA hydrogel re-transplantation improves intervertebral disc degeneration

Cell-based tissue engineering approaches have emerged as a realistic alternative for regenerative disc tissue repair. The multidirectional differentiation potential of bone marrow mesenchymal stem cells (BMSCs) to treat disc degeneration intervertebral disc degeneration has also become a viable option. We used 1% HAMA hydrogel as a carrier and co-encapsulated BMSCs and Salvianolic acid B (SalB) into the hydrogel to reduce the apoptosis of the transplanted cells. The protective effect of SalB on BMSCs was first verified in vitro using the CCK8 method, flow cytometry, and Western-Blotting, and the physical properties and biocompatibility of HAMA hydrogels were verified in vitro. The rat model was then established using the pinprick method and taken at 4 and 8 W, to examine the extent of disc degeneration by histology and immunohistochemistry, respectively. It was found that SalB could effectively reduce the apoptosis of BMSCs in vitro by activating the JAK2-STAT3 pathway. 1% HAMA hydrogels had larger pore size and better water retention, and the percentage of cell survival within the hydrogels was significantly higher after the addition of SalB to the HAMA hydrogels. In the in vivo setting, the HAMA + SalB + BMSCs group had a more pronounced delaying effect on the progression of disc degeneration compared to the other treatment groups. The method used in this study to encapsulate protective drugs with stem cells in a hydrogel for injection into the lesion has potential research value in the field of regenerative medicine.

Salvianolic acid B inhibits autophagy and activation of hepatic stellate cells induced by TGF-β1 by downregulating the MAPK pathway

In liver fibrosis, transforming growth factor-β1 (TGF-β1) can stimulate autophagy and activation of hepatic stellate cells (HSCs). Autophagy, playing a crucial role in HSCs activation, is related to liver fibrosis. Increasing evidence have suggested that antifibrosis effects of salvianolic acid B (Sal B) and their mechanisms of action, however, remain unclear. The aim of the article is to understand the role of Sal B in HSCs autophagy in liver fibrosis. Herein, we demonstrated that inducing TGF-β1 led to dramatic increase in autophagosome formation and autophagic flux in JS1 and LX2, which was mediated through the ERK, JNK, and p38 MAPK cascades. TGF-β1 significantly increased the protein of autophagy and liver fibrosis, including LC3BⅡ, ATG5, α-SMA, and Col.I; Sal B inhibits JS1 autophagy and activation by inhibiting the formation of autophagosomes and autophagic flux. Sal B significantly decreased the LC3BⅡ, ATG5, α-SMA, and Col.I protein expressions; pretreatment with autophagy inhibitors, chloroquine (CQ) and 3-methyladenine (3-MA) or silencing ATG7 further increase these reductions. However, pretreatment with autophagy agonist, rapamycin (Rapa), or overexpressed ATG5 attenuated this decrease. To further assess the importance of this mechanism, the antibody chip was used to detect the change of phosphorylation protein expression of the MAPK signaling pathway after treating JS1 with Sal B. Eleven differentially expressed proteins were verified. Sal B inhibits activation and autophagy of JS1 induced by TGF-β1 through downregulating the ERK, p38, and JNK signaling pathways, as demonstrated by downregulating p-ERK, p-JNK, and p-p38 MAPK protein expressions. In conclusion, Sal B inhibits autophagy and activation induced by TGF-β1 of HSCs possibly by downregulating the MAPK pathway.

Beneficial Effects of Carvacrol on In Vitro Models of Metabolically-Associated Liver Steatosis and Endothelial Dysfunction: A Role for Fatty Acids in Interfering with Carvacrol Binding to Serum Albumin

Background:

Carvacrol, a plant phenolic monoterpene, is largely employed as food additive and phytochemical.

Objective:

We aimed to assess the lipid lowering and protective effects of carvacrol in vitro using cellular models of hepatic steatosis and endothelial dysfunction. We also investigated if and how the binding of carvacrol to albumin, the physiological transporter for small compounds in the blood, might be altered by the presence of high levels of fatty acids (FAs).

Methods:

Hepatic FaO cells treated with exogenous FAs mimic hepatosteatosis; endothelial HECV cells exposed to hydrogen peroxide are a model of endothelial dysfunction. In these models, we measured spectrophotometrically lipid accumulation and release, lipoperoxidation, free radical production, and nitric oxide release before and after treatment with carvacrol. The carvacrol binding to albumin in the presence or absence of high levels of FAs was assessed by absorption and emission spectroscopies.

Results:

Carvacrol counteracted lipid accumulation and oxidative stress in hepatocytes and protected endothelial cells from oxidative stress and dysfunction. Moreover, high levels of FAs reduced the binding of carvacrol to albumin.

Conclusion:

The results suggest the good potential of carvacrol in ameliorating dysfunction of hepatic and endothelial cells in vitro. High levels of circulating FAs might compete with carvacrol for binding to albumin thus influencing its transport and bio-distribution.

Natural AMPK Activators in Cardiovascular Disease Prevention

Cardiovascular diseases (CVD), as a life-threatening global disease, is receiving worldwide attention. Seeking novel therapeutic strategies and agents is of utmost importance to curb CVD. AMP-activated protein kinase (AMPK) activators derived from natural products are promising agents for cardiovascular drug development owning to regulatory effects on physiological processes and diverse cardiometabolic disorders. In the past decade, different therapeutic agents from natural products and herbal medicines have been explored as good templates of AMPK activators. Hereby, we overviewed the role of AMPK signaling in the cardiovascular system, as well as evidence implicating AMPK activators as potential therapeutic tools. In the present review, efforts have been made to compile and update relevant information from both preclinical and clinical studies, which investigated the role of natural products as AMPK activators in cardiovascular therapeutics.

Silicon Oxynitrophosphide Nanoscale Coating Enhances Antioxidant Marker-Induced Angiogenesis During in vivo Cranial Bone-Defect Healing

Critical-sized bone defects are challenging to heal because of the sudden and large volume of lost bone. Fixative plates are often used to stabilize defects, yet oxidative stress and delayed angiogenesis are contributing factors to poor biocompatibility and delayed bone healing. This study tests the angiogenic and antioxidant properties of amorphous silicon oxynitrophosphide (SiONPx) nanoscale-coating material on endothelial cells to regenerate vascular tissue in vitro and in bone defects. in vitro studies evaluate the effect of silicon oxynitride (SiONx) and two different SiONPx compositions on human endothelial cells exposed to ROS (eg, hydrogen peroxide) that simulates oxidative stress conditions. in vivo studies using adult male Sprague Dawley rats (approximately 450 g) were performed to compare a bare plate, a SiONPx-coated implant plate, and a sham control group using a rat standard-sized calvarial defect. Results from this study showed that plates coated with SiONPx significantly reduced cell death, and enhanced vascular tubule formation and matrix deposition by upregulating angiogenic and antioxidant expression (eg, vascular endothelial growth factor A, angiopoetin-1, superoxide dismutase 1, nuclear factor erythroid 2-related factor 2, and catalase 1). Moreover, endothelial cell markers (CD31) showed a significant tubular structure in the SiONPx coating group compared with an empty and uncoated plate group. This reveals that atomic doping of phosphate into the nanoscale coating of SiONx produced markedly elevated levels of antioxidant and angiogenic markers that enhance vascular tissue regeneration. This study found that SiONPx or SiONx nanoscale-coated materials enhance antioxidant expression, angiogenic marker expression, and reduce ROS levels needed for accelerating vascular tissue regeneration. These results further suggest that SiONPx nanoscale coating could be a promising candidate for titanium plate for rapid and enhanced cranial bone-defect healing. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.

Colloidal Particles in Tuna Head Soup: Chemical Localization, Structural Change, and Antioxidant Property

In this work, chemical localization, structural changes, and antioxidant properties of tuna colloidal particles (TCPs) in boiling tuna head soup were examined. The results demonstrated that TCPs might be core–shell colloidal spherical structures. The hydrophobic core consisted of triglycerides and chloride ions. The hydrophilic shell layer consisted of chloride ions, sodium ions, phospholipids, protein, and glycosyl molecules. Coalescence of TCPs occurred during the boiling process, and water may enter the hydrophobic core of TCPs after the boiling time of 60 min. TCPs had excellent antioxidant properties against H₂O₂-induced human umbilical vein endothelial cell injury. It might be resulted from that TCPs could decrease cell apoptosis proportion and downregulate mRNA levels of endoplasmic reticulum-bounded chaperone protein glucose-related protein (GRP78), C/EBP homologous protein (CHOP), and activating transcription factor-4 (ATF4). This work can provide useful basic information to understand the colloidal system in foods, especially in soup. In addition, it may also promote the potential high-value-added utilization of aquatic by-products.

Salvianolic Acid B Protects Intervertebral Discs from Oxidative Stress-Induced Degeneration via Activation of the JAK2/STAT3 Signaling Pathway

OBJECTIVE

To evaluate the influence of salvianolic acid B (SAB), an antioxidant derived from Danshen, on intervertebral disc degeneration (IDD) and its possible molecular mechanisms.

METHODS

Sixty adult rats were randomly grouped (control, IDD, and SAB IDD groups). IDD was induced using needle puncture. The rats received daily administration of SAB (20 mg/kg) in the SAB IDD group while the other two groups received only distilled water. The extent of IDD was evaluated using MRI after 3 and 6 weeks and histology after 6 weeks. Oxidative stress was assessed using the ELISA method. In in vitro experiments, nucleus pulposus cells (NPCs) were treated with H2O2 (100 μM) or SAB+H2O2, and levels of oxidative stress were measured. Cell apoptosis was assessed by flow cytometry, expression levels of Bcl-2, Bax, and cleaved caspase-3 proteins. Cell proliferation rate was assessed by EdU analysis. Pathway involvement was determined by Western blotting while the influence of the pathway on NPCs was explored using the pathway inhibitor AG490.

RESULTS

The data demonstrate that SAB attenuated injury-induced IDD and oxidative stress, caused by activation of the JAK2/STAT3 signaling pathway in vivo. Oxidative stress induced by H2O2 was reversed by SAB in vitro. SAB reduced the increased cell apoptosis, cleaved caspase-3 expression, and caspase-3 activity induced by H2O2. Reduced cell proliferation and decreased Bcl-2/Bax ratio induced by H2O2 were rescued by SAB. Additionally, the JAK2/STAT3 pathway was activated by SAB, while AG490 counteracted this effect.

CONCLUSION

The results suggest that SAB protects intervertebral discs from oxidative stress-induced degeneration by enhancing proliferation and attenuating apoptosis via activation of the JAK2/STAT3 signaling pathway.

Salvianolic acid B suppresses EMT and apoptosis to lessen drug resistance through AKT/mTOR in gastric cancer cells

The drug resistance of tumor cells greatly reduces the efficacy of chemotherapy drugs in gastric cancer. Salvianolic acid B (Sal-B) is considered as a chemopreventive agent which suppresses oxidative stress and apoptosis. Therefore, the study aims to clarify the mechanism of Sal-B in drug-resistant gastric cancer cells. CCK8 assay analyzed cell viabilities after GES1, AGS and AGS/DDP cells were respectively treated by Sal-B of different concentration or after AGS/DDP cells were disposed by cisplatin (DDP) in different concentration. The colony formation, ROS generation, apoptosis, migration, invasion and EMT marker proteins were respectively analyzed through formation assay, ROS kits, TUNNEL staining, Wound healing, Transwell assays and Western blot. The results demonstrated that Sal-B acted alone or in synergy with DDP to reduce cell viabilities, initiate ROS generation, promote cell apoptosis, as well as decrease migration, invasion and EMT in AGS and AGS/DDP cells. AKT activator and mTOR activator significantly reversed the above effects of Sal-B. Collectively, Sal-B regulated proliferation, EMT and apoptosis to reduce the resistance to DDP via AKT/mTOR pathway in DDP-resistant gastric cancer cells. Sal-B could be a potential anti-drug resistance agent to chemotherapy in gastric cancer.

N‑linoleyltyrosine protects PC12 cells against oxidative damage via autophagy: Possible involvement of CB1 receptor regulation

Oxidative stress is one of the main pathogenic factors of neurodegenerative diseases. As the ligand of cannabinoid type 1 (CB1) and 2 (CB2) receptors, anandamide (AEA) exerts benign antioxidant activities. However, the instability of AEA results in low levels in vivo, which limit its further application. Based on the structure of AEA, N‑linoleyltyrosine (NITyr) was synthesized in our laboratory and was hypothesized to possess a similar function to that of AEA. To the best of our knowledge, the present study demonstrates for the first time, the activities and mechanisms of NITyr. NITyr treatment attenuated hydrogen peroxide (H2O2)‑induced cytotoxicity, with the most promiment effect observed at 1 µmol/l. Treatment with NITyr also suppressed the H2O2‑induced elevation of reactive oxygen species (ROS) and enhanced the expression of the autophagy‑related proteins, LC3‑II, beclin‑1, ATG 5 and ATG13. The autophagic inhibitor, 3‑methyladenine, reversed the effects of NITyr on ROS levels and cellular viability. Furthermore, AM251, a CB1 receptor antagonist, but not AM630 (a CB2 receptor antagonist), diminished the effects of NITyr on cell viability, ROS generation and autophagy‑related protein expression. However, NITyr increased the protein expression of both the CB1 and CB2 receptors. Therefore, NITyr was concluded to protect PC12 cells against H2O2‑induced oxidative injury by inducing autophagy, a process which may involve the CB1 receptor.

Plant-Derived Molecules α-Boswellic Acid Acetate, Praeruptorin-A, and Salvianolic Acid-B Have Age-Related Differential Effects in Young and Senescent Human Fibroblasts In Vitro

Testing and screening of plant-derived molecules on normal human cells in vitro is a widely used approach for discovering their eventual health beneficial effects for human ageing and longevity. As little is known about age-associated differential effects of such molecules, here we report that young (<25% replicative lifespan completed) and near-senescent (>90% replicative lifespan completed) human skin fibroblasts exposed for 1–15 days to a wide range of concentrations (0.1–100 μM) of the three selected phytochemicals, namely α-boswellic acid acetate (ABC), praeruptorin-A (PTA), and salvianolic acid-B (SAB) had age-related differential effects. The parameters studied were the metabolic activity (MTT assay), cellular morphological phenotype, one-step growth characteristics, expression of genes involved in the cell cycle regulation and cytokine network genes, protein levels of p53, cytosolic superoxide dismutase (SOD1) and microtubule-associated protein 1A/1B-light chain 3 (LC3), and the extent of protein carbonylation and protein aggregation as a sign of oxidative stress. All three compounds showed biphasic hormetic dose response by stimulating cell growth, survival and metabolic activity at low doses (up to 1 μM), while showing inhibitory effects at high doses (>10 μM). Furthermore, the response of early passage young cells was different from that of the late passage near-senescent cells, especially with respect to the expression of cell cycle-related and inflammation-related genes. Such studies have importance with respect to the use of low doses of such molecules as health-promoting and/or ageing-interventions through the phenomenon of hormesis.

Pharmacokinetics of Active Ingredients of Salvia miltiorrhiza and Carthamus tinctorius in Compatibility in Normal and Cerebral Ischemia Rats: A Comparative Study

Background and Objective

Dan-Hong injection, which comprises extracts of Salvia miltiorrhiza and Carthamus tinctorius, promotes blood circulation and reduces blood stasis. Combination of S. miltiorrhiza and C. tinctorius is more effective in treating cerebral ischemia than S. miltiorrhiza alone. This study aimed to examine the pharmacokinetic characteristics of four active ingredients of S. miltiorrhiza and C. tinctorius, namely danshensu (DSS), hydroxysafflor yellow A (HSYA), and salvianolic acid A (SAA) and B (SAB) in normal and cerebral ischemia rats.

Methods

Normal and cerebral ischemia rats were injected via the tail vein with each active ingredient, and blood was collected through the jaw vein at different time points. The plasma concentration of the compatibility group was analyzed by high-performance liquid chromatography, and pharmacokinetic parameters were determined using Pharmacokinetic Kinetica 4.4 software.

Results

The pharmacokinetics of the four active ingredients in the normal and cerebral ischemia rats were consistent with a two-compartment model. The area under the concentration–time curve was higher in normal rats than in cerebral ischemia rats, with a highly significant difference for SAA (P < 0.01). Clearance rates were lower in normal rats than in cerebral ischemia rats, with DSS showing the most significant difference (P < 0.01). Furthermore, there were significant differences between normal and cerebral ischemia rats in the distribution phase-elimination half life for DSS, SAA, and HSYA, as well as in the apparent volume of distribution for the central compartment for DSS and HSYA (P < 0.01). The plasma concentrations of the four active ingredients were higher in normal rats than in cerebral ischemia rats.

Conclusion

Cerebral ischemia rats showed higher drug clearance rates and longer retention times than normal rats, which may be due to destruction of the blood–brain barrier during cerebral ischemia–reperfusion. The four active ingredients likely integrated and interacted with each other to affect target sites in the brain to protect against cerebral ischemic injury.