Salvianolic acid B protects human endothelial progenitor cells against oxidative stress-mediated dysfunction by modulating Akt/mTOR/4EBP1, p38 MAPK/ATF2, and ERK1/2 signaling pathways

Bioactive components and molecular mechanisms of Salvia miltiorrhiza Bunge in promoting blood circulation to remove blood stasis

ETHNOPHARMACOLOGICAL RELEVANCE

Salvia miltiorrhiza Bunge (SM) is an outstanding herbal medicine with various traditional effects, especially promoting blood circulation to remove blood stasis. It has been widely used for centuries to treat blood stasis syndrome (BSS)-related diseases. BSS is one of the basic pathological syndromes of diseases such as cardiovascular and cerebrovascular diseases in traditional East Asian medicine, which is characterized by disturbance of blood circulation. However, the bioactive components and mechanisms of SM in the treatment of BSS have not been systematically reviewed. Therefore, this article outlines the anti-BSS effects of bioactive components of SM, concentrating on the molecular mechanisms.

AIM OF THE REVIEW

To summarize the bioactive components of SM against BSS and highlight its potential targets and signaling pathways, hoping to provide a modern biomedical perspective to understand the efficacy of SM on enhancing blood circulation to remove blood stasis.

MATERIALS AND METHODS

A comprehensive literature search was performed to retrieve articles published in the last two decades on bioactive components of SM used for BSS treatment from the online electronic medical literature database (PubMed).

RESULTS

Phenolic acids and tanshinones in SM are the main bioactive components in the treatment of BSS, including but not limited to salvianolic acid B, tanshinone IIA, salvianolic acid A, cryptotanshinone, Danshensu, dihydrotanshinone, rosmarinic acid, protocatechuic aldehyde, and caffeic acid. They protect vascular endothelial cells by alleviating oxidative stress and inflammatory damage and regulating of NO/ET-1 levels. They also enhance anticoagulant and fibrinolytic capacity, inhibit platelet activation and aggregation, and dilate blood vessels. Moreover, lowering blood lipids and improving blood rheological properties may be the underlying mechanisms of their anti-BSS. More notably, these compounds play an anti-BSS role by mediating multiple signaling pathways such as Nrf2/HO-1, TLR4/MyD88/NF-κB, PI3K/Akt/eNOS, MAPKs (p38, ERK, and JNK), and Ca2+/K+ channels.

CONCLUSIONS

Both phenolic acids and tanshinones in SM may act synergistically to target different signaling pathways to achieve the effect of promoting blood circulation.

Targeting endothelial cells with golden spice curcumin: A promising therapy for cardiometabolic multimorbidity

Cardiometabolic multimorbidity (CMM) is an increasingly significant global public health concern. It encompasses the coexistence of multiple cardiometabolic diseases, including hypertension, stroke, heart disease, atherosclerosis, and T2DM. A crucial component to the development of CMM is the disruption of endothelial homeostasis. Therefore, therapies targeting endothelial cells through multi-targeted and multi-pathway approaches hold promise for preventing and treatment of CMM. Curcumin, a widely used dietary supplement derived from the golden spice Carcuma longa, has demonstrated remarkable potential in treatment of CMM through its interaction with endothelial cells. Numerous studies have identified various molecular targets of curcumin (such as NF-κB/PI3K/AKT, MAPK/NF-κB/IL-1β, HO-1, NOs, VEGF, ICAM-1 and ROS). These findings highlight the efficacy of curcumin as a therapeutic agent against CMM through the regulation of endothelial function. It is worth noting that there is a close relationship between the progression of CMM and endothelial damage, characterized by oxidative stress, inflammation, abnormal NO bioavailability and cell adhesion. This paper provides a comprehensive review of curcumin, including its availability, pharmacokinetics, pharmaceutics, and therapeutic application in treatment of CMM, as well as the challenges and future prospects for its clinical translation. In summary, curcumin shows promise as a potential treatment option for CMM, particularly due to its ability to target endothelial cells. It represents a novel and natural lead compound that may offer significant therapeutic benefits in the management of CMM.

Co-assembled Supramolecular Hydrogel of Salvianolic Acid B and a Phosphopeptide for Enhanced Wound Healing

Supramolecular natural product gels (NPGs) have emerged as promising biomaterials for scalable and adjustable drug delivery systems. These gels possess biocompatibility, biodegradability, and the ability to mimic the extracellular matrix. Salvianolic acid B (SAB), derived from Salvia miltiorrhiza, a Chinese medicinal plant, exhibits various beneficial properties such as antioxidant, antifibrotic, and angiogenic effects. In our research, we serendipitously discovered that the co-assembly of SAB and a soluble phosphopeptide results in the formation of a robust and adhesive hydrogel termed 1&SAB hydrogel. This hydrogel effectively prolongs the retention time of the therapeutic agents on the skin's wound surface, thereby promoting wound healing. The hydrogel demonstrates antioxidant effects, enhances cell migration, accelerates angiogenesis, and inhibits scar hyperplasia. This innovative gel material offers a simple and efficient approach to managing skin wounds and holds promise for application in complex wound-healing treatments.

A mechanistic review of chinese medicine polyphenols on bone formation and resorption

Bone reconstruction includes a steady state system of bone formation and bone absorption. This tight coupling requires subtle coordination between osteoblasts and osteoclasts. If this balance is broken, it will lead to bone mass loss, bone density reduction, and bone metabolic diseases, such as osteoporosis. Polyphenols in Chinese herbal medicines are active ingredients in plant extracts with high safety and few side effects, and they can play a role in affecting bone formation and bone resorption. Some of these have estrogen-like effects and can better target bone health in postmenopausal women. The purpose of this review is to provide comprehensive information on the mechanisms underlying the relationship between traditional Chinese medicine polyphenols and bone formation or bone resorption.

Combining Network Pharmacology with Experimental Validation to Elucidate the Mechanism of Salvianolic Acid B in Treating Diabetic Peripheral Neuropathy

Background. Salvianolic acid B (Sal B) is a bioactive component of Radix Salviae, which has antiinflammation and antiapoptotic activity in diabetic complications. However, the molecular mechanism of action of Sal B on diabetic peripheral neuropathy (DPN) is unknown. This study was designed to identify a mechanism for Sal B in the treatment of DPN by using a pharmacology network, molecular docking, and in vitro experiments. Methods. Sal B and DPN-related targets from Gene Cards and OMIM platforms were retrieved and screened. Then, an analysis of possible targets with STRING and Cytoscape software was conducted. KEGG signaling pathways were determined using the R software. Subsequently, the binding capacity of Sal B to target proteins was analyzed by molecular docking and in vitro experiments. Results. A total of 501 targets related to Sal B and 4662 targets related to DPN were identified. Among these targets, 108 intersection targets were shared by Sal B and DPN. After topological and cluster analysis, 11 critical targets were identified, including p38MAPK. KEGG analysis revealed that the AGE-RAGE signaling pathway likely plays an important role in Sal B action on DPN. The p38MAPK protein is a key target in the AGE-RAGE signaling pathway. Molecular docking results suggested that Sal B and p38MAPK have excellent binding affinity (<−5 kcal/mol). The in vitro experiments revealed that Sal B downregulates the expressions of p-P38MAPK, inflammatory cytokines, and apoptosis targets, which are upregulated by hyperglycemia. Conclusion. Sal B may alter DPN by inhibiting inflammation and apoptosis activated by p38MAPK.

Salvianolic Acid B Suppresses ER Stress-Induced NLRP3 Inflammasome and Pyroptosis via the AMPK/FoxO4 and Syndecan-4/Rac1 Signaling Pathways in Human Endothelial Progenitor Cells

Mounting evidence demonstrates uncontrolled endoplasmic reticulum (ER) stress responses can activate the inflammasome, which generally results in endothelial dysfunction, a major pathogenetic factor of chronic inflammatory diseases such as atherosclerosis. Salvianolic acid B (SalB), produced by Radix Salviae, exerts antioxidative and anti-inflammatory activities in multiple cell types. However, SalB's effects on ER stress-related inflammasome and endothelial dysfunction remain unknown. Here, we showed SalB substantially abrogated ER stress-induced cell death and reduction in capillary tube formation, with declined intracellular reactive oxygen species (ROS) amounts and restored mitochondrial membrane potential (MMP), as well as increased expression of HO-1 and SOD2 in bone marrow-derived endothelial progenitor cells (BM-EPCs). ER stress suppression by CHOP or caspase-4 siRNA transfection attenuated the protective effect of SalB. Additionally, SalB alleviated ER stress-mediated pyroptotic cell death via the suppression of TXNIP/NLRP3 inflammasome, as evidenced by reduced cleavage of caspase-1 and interleukin- (IL-) 1β and IL-18 secretion levels. Furthermore, this study provided a mechanistic basis that AMPK/FoxO4/KLF2 and Syndecan-4/Rac1/ATF2 signaling pathway modulation by SalB substantially prevented BM-EPCs damage associated with ER stress by decreasing intracellular ROS amounts and inducing NLRP3-dependent pyroptosis. In summary, our findings identify that ER stress triggered mitochondrial ROS release and NLRP3 generation in BM-EPCs, while SalB inhibits NLRP3 inflammasome-mediated pyroptotic cell death by regulating the AMPK/FoxO4/KLF2 and Syndecan-4/Rac1/ATF2 pathways. The current findings reveal SalB as a potential new candidate for the treatment of atherosclerotic heart disease.

Traditional Chinese Medicine Compound-Loaded Materials in Bone Regeneration

Bone is a dynamic organ that has the ability to repair minor injuries via regeneration. However, large bone defects with limited regeneration are debilitating conditions in patients and cause a substantial clinical burden. Bone tissue engineering (BTE) is an alternative method that mainly involves three factors: scaffolds, biologically active factors, and cells with osteogenic potential. However, active factors such as bone morphogenetic protein-2 (BMP-2) are costly and show an unstable release. Previous studies have shown that compounds of traditional Chinese medicines (TCMs) can effectively promote regeneration of bone defects when administered locally and systemically. However, due to the low bioavailability of these compounds, many recent studies have combined TCM compounds with materials to enhance drug bioavailability and bone regeneration. Hence, the article comprehensively reviewed the local application of TCM compounds to the materials in the bone regeneration in vitro and in vivo. The compounds included icariin, naringin, quercetin, curcumin, berberine, resveratrol, ginsenosides, and salvianolic acids. These findings will contribute to the potential use of TCM compound-loaded materials in BTE.

ox-LDL-Induced Endothelial Progenitor Cell Oxidative Stress via p38/Keap1/Nrf2 Pathway

Background

Nrf2 which was recently reported to regulate the antioxidant genes and cellular redox regulators was highly expressed in EPCs. However, its role in ox-LDL-induced EPC oxidative stress and apoptosis has not been fully illustrated.

Methods

EPCs isolated from human peripheral blood mononuclear cells were treated with different concentrations of ox-LDL, Keap1 siRNA, and a specific p38 MAPK inhibitor SB203580 and then used to assay the cytoplasmic Nrf2, nuclear Nrf2, NAD(P) H:quinone oxidoreductase 1 (NQO1) and Bax/Bcl-2 levels with Western blot, NQO1 mRNA levels with RT-PCR, ROS levels with H2DCF-DA, loss/disruption of mitochondrial membrane potential with JC-1, apoptosis with Annexin V and PI, migration with transwell chambers, and tube formation with Matrigel.

Results

ox-LDL decreased the nuclear Nrf2/Histone H3 to cytoplasmic Nrf2/GAPDH ratio, NQO1 mRNA, and protein levels. ox-LDL enhanced ROS production, induced the loss of membrane potential, and increased the cell shrinkage, pyknotic nuclei, and apoptosis of EPCs. Keap1 siRNA increased Nrf2 nuclear translocation, NQO1 mRNA transcription, and protein expression and prevented ROS generation and formation of JC-1 monomers. ox-LDL increased the activation of p38. SB203580 significantly eliminated ox-LDL induced inhibition of Nrf2 nuclear translocation, depression of NQO1 mRNA transcription, generation of ROS, and formation of JC-1 monomers in EPCs. Keap1 siRNA decreased the Bax/Bcl-2 ratio which was increased by ox-LDL in EPCs. ox-LDL decreased EPC migration and tube formation. Keap1 siRNA preserved the migration and tube formation of EPCs.

Conclusion

ox-LDL activated EPCs p38/Keap1/Nrf2 pathway and induced oxidative stress, dysfunction, and apoptosis of EPCs.

Salvianolic acid B ameliorates vascular endothelial dysfunction through influencing a bone morphogenetic protein 4-ROS cycle in diabetic mice

AIM

This study investigated the roles of bone morphogenetic protein-4 (BMP4) and ROS in diabetic endothelial dysfunction and explored whether Salvianolic acid B (Sal B) improved endothelial function by affecting BMP4-ROS in diabetic mice.

MAIN METHODS

db/db mice were orally administrated with Sal B (10 mg/kg/day) for one week while db/m + mice were injected with adenoviral vectors delivering BMP4 (3 × 10⁸ pfu) and then received one week-Sal B treatment. ROS levels were assayed by DHE staining. Protein expression and phosphorylation were evaluated by Western blot. Aortic rings were suspended in myograph for force measurement. Flow-mediated dilatations in the second-order mesenteric arteries were determined by pressure myograph.

KEY FINDINGS

We first revealed the existence of a BMP4-ROS cycle in db/db mice, which stimulated p38 MAPK/JNK/caspase 3 and thus participated in endothelial dysfunction. One week-treatment or 24 h-incubation with Sal B disrupted the cycle, suppressed p38 MAPK/JNK/caspase 3 cascade, and improved endothelium-dependent relaxations (EDRs) in db/db mouse aortas. Importantly, in vivo Sal B treatment also improved flow-mediated dilatation in db/db mouse second order mesenteric arteries. Furthermore, in vivo BMP4 overexpression induced oxidative stress, stimulated p38 MAPK/JNK/caspase 3, and impaired EDRs in db/m + mouse aortas, which were all reversed by Sal B.

SIGNIFICANCE

The present study demonstrates that Sal B ameliorates endothelial dysfunction through breaking the BMP4-ROS cycle and subsequently inhibiting p38 MAPK/JNK/caspase 3 in diabetic mice and provides evidence for the additional new mechanism underlying the benefit of Sal B against diabetic vasculopathy.

Salvia miltiorrhiza Protects Endothelial Dysfunction against Mitochondrial Oxidative Stress

Salvia miltiorrhiza (SM) is a common traditional Chinese medicine used in the treatment of cardiovascular and cerebrovascular diseases. Endothelial dysfunction plays an important role in the pathology of cardiovascular diseases. Endothelial dysfunction may induce inflammation and change vascular tone and permeability. The main pathological mechanism of endothelial dysfunction is the formation of reactive oxygen species (ROS). Mitochondria are the main source of energy and can also produce large amounts of ROS. Recent studies have shown that extracts of SM have antioxidative, anti-inflammatory, and antithrombus properties. In this review, we discuss the mechanism of oxidative stress in the mitochondria, endothelial dysfunction, and the role of SM in these oxidative events.

Pristimerin synergistically sensitizes conditionally reprogrammed patient derived-primary hepatocellular carcinoma cells to sorafenib through endoplasmic reticulum stress and ROS generation by modulating Akt/FoxO1/p27kip1 signaling pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-associated mortality worldwide. Sorafenib (SORA), as a first-line therapeutic drug, has been used to treat HCC, but resistance poses a major limitation on the efficacy of SORA chemotherapy. Pristimerin (PRIS), a natural bioactive component isolated from various plant species in the Celastraceae and Hippocrateaceae families, has been reported to exhibit outstanding antitumor effects in several types of cells in vitro.

PURPOSE

The aim of this study was to investigate whether PRIS can exert synergistic anti-tumor effects with the combination of SORA, and if so, through what mechanism.

METHODS

Conditionally reprogrammed patient derived-primary hepatocellular carcinoma cells (CRHCs) were isolated from human liver cancer tissues and treated with SORA and PRIS. Cell proliferation, apoptosis, migration and tube formation ability were detected by DNA content quantification, flow cytometry, transwell assay and Matrigel-based angiogenesis assay. Gene and protein expression were assessed by qRT-PCR and Western blot respectively.

RESULTS

Initially, we observed that the combination of the two drugs had a much stronger inhibitory effect on CRHCs growth than either drug alone. Moreover, the combination of 2 µM SORA and 1 µM PRIS exhibited a significant anti‑migrative and anti-invaded effect on CRHCs, and remarkably inhibited capillary structure formation of Human Umbilical Vein Endothelial Cells (HUVECs). Furthermore, the combined treatment with SORA and PRIS synergistically induced intrinsic apoptosis in CRHCs, involving a caspase-4-dependent mechanism paralleled by an increased Bax/Bcl-xL ratio. These activities were mediated through ROS generation and the induction of endoplasmic reticulum (ER) stress and mitochondrial dysfunction. GRP78 silencing or ER stress inhibitor 4-phenylbutyric acid administration was revealed to abolish the anticancer effects of PRIS, indicating the critical role of GRP78 in mediating the bioactivity of PRIS. The present study also provides mechanistic evidence that PRIS modulated the Akt/FoxO1/p27^kip1 signaling pathway, which is required for mitochondrial-mediated intrinsic apoptosis, activation of ER stress, and stimulation of caspase-4 induced by PRIS, and, consequently resulting in suppressed cell viability, migration and angiogenesis co-treated with SORA in CRHCs.

CONCLUSION

Our results suggest the use of PRIS as sensitizers of chemotherapy paving the way for innovative and promising targeted chemotherapy-based therapeutic strategies in human HCC.

Salvianolic acid B inhalation solution enhances antifibrotic and anticoagulant effects in a rat model of pulmonary fibrosis

The purpose of this study was to investigate the antifibrotic effect and anticoagulant ability of salvianolic acid B (SAB) inhalation solution on bleomycin (BLM)-induced idiopathic pulmonary fibrosis (IPF) in rats. We investigated how the osmotic pressure and concentration of SAB in an aerosol exerted effects. We also determined the aerodynamic particle size distribution and the uniformity of the delivery dose; these parameters were found to be suitable for inhalation. Compared with BLM group, the levels of hydroxyproline (HYP), collagen-1 (Col-1), tissue factor (TF) / coagulation factor VII (TF-VIIa), activated coagulation factor X (FXa), thrombin-antithrombin complex (TAT), fibrinogen degradation product (FDP) and plasminogen activator inhibitor-1 (PAI-1) decreased in SAB group. The increased expression of coagulation factor Ⅱ (FⅡ), coagulation factor X (FX), tissue type plasminogen activator (t-PA) and urokinase type plasminogen activator (u-PA) proved that SAB has obvious antifibrotic and anticoagulant effects. Western blotting and immunofluorescence further showed that compared with the BLM group, the SAB group of rats exhibited significant reductions in the expression levels of protease-activated receptors-1 (PAR-1) and phospho-protein kinase C (p-PKC) and increased expression levels of protein kinase C (PKC) in lung tissue. Furthermore, SAB reduced the infiltration of lymphocytes and neutrophils, protected the basic structure of the lung from destruction, inhibited the proliferation of fibrous tissue. Collectively, our data revealed that SAB may exert its antifibrotic and anticoagulant effects by preventing the expression of PAR-1 and phosphorylation of PKC.

Bioactive Herbal Extracts of Traditional Chinese Medicine Applied with the Biomaterials: For the Current Applications and Advances in the Musculoskeletal System

Traditional Chinese medicine (TCM) has demonstrated superior therapeutic effect for musculoskeletal diseases for thousands of years. Recently, the herbal extracts of TCM have received rapid advances in musculoskeletal tissue engineering (MTE). A literature review collecting both English and Chinese references on bioactive herbal extracts of TCM in biomaterial-based approaches was performed. This review provides an up-to-date overview of application of TCMs in the field of MTE, involving regulation of multiple signaling pathways in osteogenesis, angiogenesis, anti-inflammation, and chondrogenesis. Meanwhile, we highlight the potential advantages of TCM, opening the possibility of its extensive application in MTE. Overall, the superiority of traditional Chinese medicine turns it into an attractive candidate for coupling with advanced additive manufacturing technology.

Andrade-Oliveira Salvianolic Acid B Modulates Caspase-1-Mediated Pyroptosis in Renal Ischemia-Reperfusion Injury via Nrf2 Pathway

Acute kidney injury (AKI) is a serious disease characterized by a rapid decline in kidney function. Oxidative stress is the primary pathogenesis of AKI. Salvianolic acid B (SalB), a water-soluble compound extracted from Salvia miltiorrhiza, possesses a potent antioxidant activity. Here, we investigated the protective effect of SalB against renal ischemia-reperfusion injury (I/R) in mice. Briefly, by analyzing renal function, oxidative stress markers and inflammatory biomarkers, we found that SalB could improve kidney damage, reduce oxidative stress and inflammatory factor levels. Interestingly, the expression of the NLR family pyrin domain-containing 3 (NLRP3), caspase-1, pyroptosis related proteins gasdermin D (GSDMD) and interleukin (IL)-1β, which were significantly upregulated in the kidney tissues of I/R group, was effectively reversed by SalB. Meanwhile, renal tubular epithelial cells hypoxia and reoxygenation model was used to explore pyroptosis of caspase-1-dependent. Further mechanism study showed that the SalB pretreatment could promote the increase of nuclear factor erythroid-2 related factor 2 (Nrf2) nuclear accumulation, which significantly suppressed oxidative stress, proinflammatory cytokines, NLRP3 inflammasome activation and pyroptosis. These results indicate that SalB can inhibit caspase-1/GSDMD-mediated pyroptosis by activating Nrf2/NLRP3 signaling pathway, resulting in alleviating I/R injury in mice.

Salvianolic Acid B Improves Postresuscitation Myocardial and Cerebral Outcomes in a Murine Model of Cardiac Arrest: Involvement of Nrf2 Signaling Pathway

Survival and outcome of cardiac arrest (CA) are dismal despite improvements in cardiopulmonary resuscitation (CPR). Salvianolic acid B (Sal B), extracted from Salvia miltiorrhiza, has been investigated for its cardioprotective properties in cardiac remodeling and ischemic heart disease, but less is known about its role in CA. The aim of this study was to learn whether Sal B improves cardiac and neurologic outcomes after CA/CPR in mice. Female C57BL/6 mice were subjected to eight minutes of CA induced by an intravenous injection of potassium chloride (KCl), followed by CPR. After 30 seconds of CPR, mice were blindly randomized to receive either Sal B (20 mg/kg) or vehicle (normal saline) intravenously. Hemodynamic variables and indices of left ventricular function were determined before CA and within three hours after CPR, the early postresuscitation period. Sal B administration resulted in a remarkable decrease in the time required for the return of spontaneous circulation (ROSC) in animals that successfully resuscitated compared to the vehicle-treated mice. Myocardial performance, including cardiac output and left ventricular systolic (dp/dt_max) and diastolic (dp/dt_min) function, was clearly ameliorated within three hours of ROSC in the Sal B-treated mice. Moreover, Sal B inhibited CA/CPR-induced cardiomyocyte apoptosis and preserved mitochondrial morphology and function. Mechanistically, Sal B dramatically promoted Nrf2 nuclear translocation through the downregulation of Keap1, which resulted in the expression of antioxidant enzymes, including HO-1 and NQO1, thereby counteracted the oxidative damage in response to CA/CPR. The aforementioned antiapoptotic and antioxidant effects of Sal B were impaired in the setting of gene silencing of Nrf2 with siRNA in vitro model. These improvements were associated with better neurological function and increased survival rate (75% vs. 40%, p < 0.05) up to 72 hours postresuscitation. Our findings suggest that the administration of Sal B improved cardiac function and neurological outcomes in a murine model of CA via activating the Nrf2 antioxidant signaling pathway, which may represent a novel therapeutic strategy for the treatment of CA.

Pristimerin Exacerbates Cellular Injury in Conditionally Reprogrammed Patient-Derived Lung Adenocarcinoma Cells by Aggravating Mitochondrial Impairment and Endoplasmic Reticulum Stress through EphB4/CDC42/N-WASP Signaling

Lung cancer is the most common and lethal malignant disease for which the development of efficacious chemotherapeutic agents remains an urgent need. Pristimerin (PRIS), a natural bioactive component isolated from various plant species in the Celastraceae and Hippocrateaceae families, has been reported to exhibit outstanding antitumor effects in several types of cells. However, the underlying mechanisms involved remain poorly understood. Here, we reported the novel finding that PRIS significantly suppressed lung cancer growth in conditionally reprogrammed patient-derived lung adenocarcinoma cells (CRLCs). We demonstrated that PRIS inhibited the cell viabilities, migrative and invaded abilities, and capillary structure formation of CRLCs. Furthermore, our results clarified that PRIS induced mitochondrial dysfunction through reactive oxygen species (ROS) generation, activation of caspase-9, caspase-3, and caspase-4, and expression of endoplasmic reticulum (ER) stress-associated proteins. Inhibition of ER stress by 4-PBA (4-phenylbutyric acid, a specific ER stress inhibitor) or CHOP siRNA transfection ameliorated PRIS-induced loss of mitochondrial membrane potential and intrinsic apoptosis. The present study also provides mechanistic evidence that PRIS suppressed the EphB4/CDC42/N-WASP signaling pathway, which is required for mitochondrial-mediated intrinsic apoptosis, activation of ER stress, and stimulation of caspase-4 induced by PRIS, and consequently resulting in suppressed cell viability, migration, and angiogenesis in CRLCs. Taken together, by providing a mechanistic insight into the modulation of ER stress-induced cell death in CRLCs by PRIS, we suggest that PRIS has a strong potential of being a new antitumor therapeutic agent with applications in the fields of human lung adenocarcinoma.

Downregulation of RRM2 Attenuates Retroperitoneal Liposarcoma Progression via the Akt/mTOR/4EBP1 Pathway: Clinical, Biological, and Therapeutic Significance

Background

Retroperitoneal liposarcoma (RLPS) is a rare tumor with high recurrence rate. Ribonucleotide reductase small subunit M2 (RRM2) protein is essential for DNA synthesis and replication. Our previous study has demonstrated that RRM2 downregulation inhibited the proliferation of RLPS cells, but further association between RRM2 and RLPS and relevant mechanisms remains to be explored.

Methods

RRM2 expression was evaluated in RLPS tumor tissues and cell lines by using real-time PCR and immunohistochemical analysis. The effect of RRM2 downregulation on cell proliferation, apoptosis, cell cycle, cell migration and invasion was tested by lentivirus. The effect of RRM2 inhibition on tumor growth in vivo was assessed by using patient-derived tumor xenograft (PDX) of RLPS and RRM2 inhibitor. The underlying mechanisms of RRM2 in RLPS were explored by protein microarray and Western blotting.

Results

The results showed that RRM2 mRNA expression was higher in RLPS tissues than in normal fatty tissues (P<0.001). RRM2 expression was higher in the dedifferentiated, myxoid/round cell, and pleomorphic subtypes (P=0.027), and it was also higher in the high-grade RLPS tissues compared to that in the low-grade RLPS tissues (P=0.004). There was no correlation between RRM2 expression and overall survival (OS) or disease-free survival (DFS) in this group of RLPS patients (P>0.05). RRM2 downregulation inhibited cell proliferation, promoted cell apoptosis, facilitated cell cycle from G1 phase to S phase and inhibited cell migration and invasion. Inhibition of RRM2 suppressed tumor growth in NOD/SCID mice. Protein microarray and Western blot verification showed that activity of Akt/mammalian target of rapamycin/eukaryotic translation initiation factor 4E binding protein 1 (Akt/mTOR/4EBP1) pathway was downregulated along with RRM2 downregulation.

Conclusion

RRM2 was overexpressed in RLPS tissues, and downregulation of RRM2 could inhibit RLPS progression. In addition, suppression of RRM2 is expected to be a promising treatment for RLPS patients.

Quercetin mitigates monosodium glutamate-induced excitotoxicity of the spinal cord motoneurons in aged rats via p38 MAPK inhibition

Various studies reported the possibility of deterioration of blood-brain barrier (BBB) integrity owing to the aging process. The current work was performed to investigate the ability of Monosodium glutamate (MSG) to cross BBB in aged rats, the damage affecting the anterior horn cells of the spinal cord due to excitotoxicity, and the mechanisms by which quercetin (Que) administration might suppress such damage. Forty male rats aged 18 months were assigned equally to 4 groups: control group, Que group (received Que, 20 mg/kg/d intraperitonealy for 10 days), MSG group (received MSG, 4.0 g/kg/d subcutaneously for 10 days), MSG + Que group (received both Que and MSG as done in the Que and MSG groups respectively). Cervical spinal cord specimens were obtained and prepared for routine histological study, immunohistochemical staining by caspase-3 and glial fibrillary acidic protein (GFAP), assessment of oxidative stress, measurement of cytokines, assessment of caspase-3 activity and GFAP levels as well as for western blotting of phosphorylated activating transcription factor 2 (ATF2^pp) as an indicator for the activity of p38 mitogen-activated protein kinase (MAPK). The MSG group revealed variable degenerative and apoptotic changes in the motoneurons and neuroglia, a marked rise in the cytoplasmic caspase-3 expression in motoneurons and a significant reduction (p < 0.001) in the astrocyte surface area percentage. In addition, the spinal cord tissue exhibited a significant elevation (p < 0.001) in the levels of malondialdehyde (MDA), IL-1, IL-6, TNFα, INFɣ, caspase-3 activity and ATF2 ^pp expression as well as a significant reduction (p < 0.001) in SOD, IL-10 and GFAP levels compared with the control group. On combining Que with MSG, most of the degenerative changes were reversed and all the impaired parameters were nearly normalized except for IL-6 and GFAP levels which were still significantly (p < 0.05) different from those of the control group. Our study suggests that MSG can break through the BBB of the aged rats and induce excitotoxicity dependent changes in spinal cord motoneurons. Most of these changes were reversed by Que probably via targeting the p38 MAPK-ATF2 pathway, antagonizing oxidative stress, anti-inflammatory effect, and promoting GFAP expression.

Total Salvianolic Acid Injection Prevents Ischemia/Reperfusion-Induced Myocardial Injury Via Antioxidant Mechanism Involving Mitochondrial Respiratory Chain Through the Upregulation of Sirtuin1 and Sirtuin3

Supplemental Digital Content is available in the text

Sirtuin1 (Sirt1) and Sirtuin3 (Sirt3) are known to participate in regulating mitochondrial function. However, whether Total Salvianolic Acid Injection (TSI) protects against myocardial ischemia/reperfusion (I/R) injury through regulating Sirt1, Sirt3, and mitochondrial respiratory chain complexes is unclear. The aim of this study was to explore the effects of TSI on I/R-induced myocardial injury and the underlying mechanism. Male Sprague–Dawley rats were subjected to 30 min occlusion of the left anterior descending coronary artery followed by 90 min reperfusion with or without TSI treatment (8 mg/kg/h). The results demonstrated that TSI attenuated I/R-induced myocardial injury by the reduced infarct size, recovery of myocardial blood flow, and decreased cardiac apoptosis. Moreover, TSI protected heart from oxidative insults, such as elevation of myeloperoxidase, malondialdehyde, hydrogen peroxide, ROS, as well as attenuated I/R-elicited downregulation of Sirt1, Sirt3, NADH dehydrogenase [ubiquinone] 1 alpha subcomplex 10 (NDUFA10), succinate dehydrogenase complex, subunit A, flavoprotein variant (SDHA), and restoring mitochondrial respiratory chain complexes activity. The in vitro study in H9c2 cells using siRNA transfection further confirmed the critical role of Sirt1 and Sirt3 in the effect of TSI on the expression of NDUFA10 and SDHA. These results demonstrated that TSI attenuated I/R-induced myocardial injury via inhibition of oxidative stress, which was related to the activation of NDUFA10 and SDHA through the upregulation of Sirt1 and Sirt3.

Salvianolic acid B inhibits ototoxic drug-induced ototoxicity by suppression of the mitochondrial apoptosis pathway

It has been claimed that salvianolic acid B (Sal B), a natural bioactive antioxidant, exerts protective effects in various types of cells. This study aims to evaluate the antioxidant and anti‐apoptosis effects of Sal B in a cultured HEI‐OC1 cell line and in transgenic zebrafish (Brn3C: EGFP). A CCK‐8 assay, Annexin V Apoptosis Detection Kit, TUNEL and caspase‐3/7 staining, respectively, examined apoptosis and cell viability. The levels of reactive oxygen species (ROS) were evaluated by CellROX and MitoSOX Red staining. JC‐1 staining was employed to detect the mitochondrial membrane potential (ΔΨm). Western blotting was used to assess expressions of Bax and Bcl‐2. The expression pattern of p‐PI3K and p‐Akt was determined by immunofluorescent staining. We found that Sal B protected against neomycin‐ and cisplatin‐induced apoptotic features, enhanced cell viability and accompanied with decreased caspase‐3 activity in the HEI‐OC1 cells. Supplementary experiments determined that Sal B reduced ROS production (increased ΔΨm), promoted Bcl‐2 expression and down‐regulated the expression of Bax, as well as activated PI3K/AKT signalling pathways in neomycin‐ and cisplatin‐injured HEI‐OC1 cells. Moreover, Sal B markedly decreased the TUNEL signal and protected against neomycin‐ and cisplatin‐induced neuromast HC loss in the transgenic zebrafish. These results unravel a novel role for Sal B as an otoprotective agent against ototoxic drug–induced HC apoptosis, offering a potential use in the treatment of hearing loss.

Salvianolic Acid B-Loaded Chitosan/hydroxyapatite Scaffolds Promotes The Repair Of Segmental Bone Defect By Angiogenesis And Osteogenesis

Background

Salvianolic acid B has been proven as an effective drug to promote osteogenesis and angiogenesis which could be beneficial for bone repair.

Purpose

The objective of this study was to construct a salvianolic acid B-loaded chitosan/hydroxyapatite (Sal B-CS/HA) bone scaffold with controlled release and effective bioactivity.

Methods

The characteristics, controlled release behavior and bioactivity of Sal B-CS/HA scaffold were evaluated in vitro. The bone repair effect was evaluated in the rabbit radius defect model.

Results

The results showed that chemical and physical characteristics of salvianolic acid B and chitosan/hydroxyapatite (CS/HA) material did not obviously change after the drug loading procedure; the drug release of salvianolic acid B was stable and continuous from the Sal B-CS/HA scaffold for 8 weeks in vitro; the biocompatibility of the Sal B-CS/HA was favorable by evaluation of cell morphology and proliferation; the osteogenic and angiogenic bioactivities of the Sal B-CS/HA scaffold were proved to be effective by in vivo and in vitro tests.

Conclusion

Our results suggest that this salvianolic acid B-loaded bone scaffold has potential to be used for bone defect repair with both osteogenic and angiogenic bioactivities.

Salvianolic acid B inhibits Ang II-induced VSMC proliferation in vitro and intimal hyperplasia in vivo by downregulating miR-146a expression

BACKGROUND

Salvianolic acid B (Sal B), a water-soluble compound extracted from Salvia miltiorrhiza that has been widely used to treat cardiovascular diseases for hundreds of years in China, exerts cardiovascular protection by multiple mechanisms. miR-146a is involved in vascular smooth muscle cell (VSMC) phenotypic modulation and proliferation. However, it has yet to be investigated whether the cardiovascular protective effect of Sal B is mediated by miR-146a.

PURPOSE

To determine the relationship among the cardiovascular protective effect of Sal B, miR-146a expression, and VSMC proliferation.

METHODS

MTS assay and cell counting were performed to evaluate the effect of Ang II, Sal B and miR-146a on VSMC proliferation. The neointima hyperplasia was assessed by hematoxylin/eosin staining. qRT-PCR was used to detect the expression of miR-146a, KLF5, cyclin D1 and PCNA. Western blot analysis was used to detect the expressions of KLF5, cyclin D1 and PCNA after miR-20b-5p was knocked down or overexpressed in VSMC.

RESULTS

Sal B suppressed intimal hyperplasia induced by carotid artery ligation and decreased Ang II-induced VSMC proliferation by down-regulating the positive cell-cycle regulators KLF5 and cyclin D1. Further experiments showed that VSMC proliferation and upregulation of KLF5 and cyclin D1 induced by Ang II were accompanied by elevated miR-146a level. Furthermore, overexpression of miR-146a promoted and knockdown of miR-146a reduced Ang II-induced VSMC proliferation and ameliorated intimal hyperplasia induced by carotid artery ligation. Sal B inhibited Ang II-induced VSMC proliferation by suppressing miR-146a expression.

CONCLUSION

Sal B inhibited Ang II-induced VSMC proliferation in vitro and intimal hyperplasia in vivo by downregulating miR-146a expression.

Salvianolic Acid B Attenuates Apoptosis of HUVEC Cells Treated with High Glucose or High Fat via Sirt1 Activation

High glucose and high fat are important inducements for the development and progression of diabetic cardiopathy. Salvianolic acid B (SAB), which is the most abundant and bioactive compound in Danshen, attenuates oxidative stress-related disorders, such as cardiovascular diseases, cerebral ischemia, and diabetes. However, the effect of SAB on diabetic cardiopathy is not clear. The aim of study was to investigate the effect and the underlying molecular mechanisms of SAB on diabetic cardiopathy in vitro model. The human umbilical vein endothelial (HUVEC) cells were treated with high glucose (HG, 30 mM) or high fat (palmitic acid, PA, 0.75 mM) in the presence or absence of SAB (100, 200, and 400 mg/L) and incubated for 24 h. We found that HG or PA induced apoptosis of HUVEC cells, while treatment with SAB inhibited the apoptosis. We also found that SAB reversed HG- or PA-induced oxidative stress, apoptosis cell cytokines production, and expression of thioredoxin-interacting protein (TXNIP). Moreover, SAB increased HG- or PA-induced expression of Sirtuin 1 (Sirt1), a nicotinamide adenine dinucleotide- (NAD⁺-) dependent histone deacetylase. Exposure of HUVEC cells to Ex527 (Sirt1 inhibitor) suppressed the effect of SAB on acetyl-p53 and procaspase-3 expressions. In conclusion, the results suggested that SAB could attenuate HUVEC cells damage treated with HG or PA via Sirt1 and might be a potential therapy agent for the diabetic cardiopathy treatment.

Cerebroprotection by salvianolic acid B after experimental subarachnoid hemorrhage occurs via Nrf2- and SIRT1-dependent pathways

Salvianolic acid B (SalB), a natural polyphenolic compound extracted from the herb of Salvia miltiorrhiza, possesses antioxidant and neuroprotective properties and has been shown to be beneficial for diseases that affect vasculature and cognitive function. Here we investigated the protective effects of SalB against subarachnoid hemorrhage (SAH)-induced oxidative damage, and the involvement of underlying molecular mechanisms. In a rat model of SAH, SalB inhibited SAH-induced oxidative damage. The reduction in oxidative damage was associated with suppressed reactive oxygen species generation; decreased lipid peroxidation; and increased glutathione peroxidase, glutathione, and superoxide dismutase activities. Concomitant with the suppressed oxidative stress, SalB significantly reduced neurologic impairment, brain edema, and neural cell apoptosis after SAH. Moreover, SalB dramatically induced nuclear factor-erythroid 2-related factor 2 (Nrf2) nuclear translocation and increased expression of heme oxygenase-1 and NADPH: quinine oxidoreductase-1. In a mouse model of SAH, Nrf2 knockout significantly reversed the antioxidant effects of SalB against SAH. Additionally, SalB activated sirtuin 1 (SIRT1) expression, whereas SIRT1-specific inhibitor sirtinol pretreatment significantly suppressed SalB-induced SIRT1 activation and Nrf2 expression. Sirtinol pretreatment also reversed the antioxidant and neuroprotective effects of SalB. In primary cultured cortical neurons, SalB suppressed oxidative damage, alleviated neuronal degeneration, and improved cell viability. These beneficial effects were associated with activation of the SIRT1 and Nrf2 signaling pathway and were reversed by sirtinol treatment. Taken together, these in vivo and in vitro findings suggest that SalB provides protection against SAH-triggered oxidative damage by upregulating the Nrf2 antioxidant signaling pathway, which may be modulated by SIRT1 activation.

DPPH-HPLC-MS assisted rapid identification of endothelial protective substances from Xiao-Ke-An

ETHNOPHARMACOLOGICAL RELEVANCE

Xiao-Ke-An formula (XKA) is a Chinese medicine widely used for treating diabetes and associated complications. Endothelial protection is thought to be one of its therapeutic mechanisms. However, the protective effect of XKA on endothelial cells remains unclear, especially in oxidative injury induced endothelial dysfunction.

MATERIALS AND METHODS

A novel strategy to rapidly screen and identify potential endothelial protective substances from XKA was established by combining the 2,2'-diphenyl-1-picrylhydrazyl high performance liquid chromatography coupled with mass spectrometry (DPPH-HPLC-MS) approach with cell-based verification. Firstly, the DPPH-HPLC-MS approach was employed to identify the antioxidants in XKA. Then, the potent endothelial protective effect of XKA, and the potential active substances and mechanism of action were revealed in EA.hy926 cells injured by tert-butyl hydroperoxide (t-BHP).

RESULTS

XKA exhibited potent antioxidant activity and endothelial protective effect. Phenolic acids derived from Salvia miltiorrhiza Bunge, root and rhizome, xanthones from Anemarrhena asphodeloides Bunge, rhizome, and acteoside from Rehmannia glutinosa (Gaertn.) DC., root, were identified as the major endothelial protective components in XKA.

CONCLUSIONS

An efficient method for rapid identifying endothelial protective substances from complex mixtures was developed and used to identify the major endothelial protective components in XKA. This method would help reveal the material base of herbal medicine with endothelial protective effect, and could also be applied to discover novel natural-origin endothelial protective substances.

Midazolam prevents motor neuronal death from oxidative stress attack mediated by JNK-ERK pathway

Midazolam is a sedative used by patients with mechanical ventilation. However, the potential clinical value is not fully explored. In this report, we made use of a neuroblastoma-spinal cord hybrid motor neuron-like cell line NSC34, and elucidated the potential role of Midazolam on these cells under the insult of oxidative stress. We found the protective effect of Midazolam on motor neurons against cytotoxicity induced by the combination of oligomycin A and rotenone (O/R) or phenylarsine oxide. The characteristics of apoptosis, such as the ratio of TUNEL+ cells or the expression level of cleaved Caspase-3, was decreased by 22 or 45% in the presence of Midazolam. Furthermore, this effect was correlated with the JNK-ERK signaling pathway. Either phosphorylation of ERK or JNK was positively or negatively modulated with the treatment of Midazolam in NSC34 cells attacked by reactive oxygen species. Meanwhile, inhibition or activation of the JNK-ERK pathway regulated the protective effect of Midazolam on NSC34 cells with oxidative stress insult. Collectively, this study elucidated a previously unidentified clinical effect of Midazolam, and put forward the great promise that Midazolam may be considered as a potential candidate to the treatment of motor neuron disease.

Inhibition of Human UGT1A1-Mediated Bilirubin Glucuronidation by Polyphenolic Acids Impact Safety of Popular Salvianolic Acid A/B-Containing Drugs and Herbal Products

Bilirubin-related adverse reactions (ADR, e.g., jaundice and hyperbilirubinemia) induced by herbs rich in certain polyphenolic acids are widely reported. However, the causes and the mechanisms underlying these ADR are not well understood. The purpose of this article is to determine the mechanism by which certain polyphenolic acids inhibit UGT1A1-mediated bilirubin glucuronidation, leading to jaundice or hyperbilirubinemia. We investigated in vitro inhibitory effects on bilirubin glucuronidation of salvianolic acid A (SAA), salvianolic acid B (SAB), danshensu (DSS), protocatechuic aldehyde (PA), and rosmarinic acid (RA), as well as two Salvia miltiorrhiza injections (DSI and CDI) rich in polyphenolic acids. The results showed that average formation rates of three bilirubin glucuronides displayed a significant difference (p < 0.05) and the formation of monoglucuronide was favored regardless if an inhibitor was present or not. SAA, SAB, DSI, and CDI, but not DSS, PA, and RA, significantly inhibited human UGT1A1-mediated bilirubin glucuronidation via a mixed-type inhibitory mechanism. Average IC50 values of SAA, SAB, DSI, and CDI-mediated inhibition of bilirubin glucuronidation were bilirubin concentration-dependent, and their values (against total bilirubin glucuronidation) were in the range 0.44 ± 0.02 to 0.86 ± 0.04 μg/mL (for SAA), 4.22 ± 0.30 to 12.50 ± 0.93 μg/mL (for SAB), 9.29 ± 0.76 to 18.82 ± 0.63 μg/mL (for DSI), and 9.18 ± 2.00 to 22.36 ± 1.39 μg/mL (for CDI), respectively. In conclusion, SAA and its analog SAB are the main ingredients responsible for inhibition of bilirubin glucuronidation by DSI and CDI, whose use is associated with many high bilirubin-related ADR.

Kaiso protects human umbilical vein endothelial cells against apoptosis by differentially regulating the expression of B-cell CLL/lymphoma 2 family members

Endothelial cell injury can promote the development of various cardiovascular diseases, thus, fully understanding the mechanisms underlying the maintenance of vascular endothelial cell homoeostasis may help prevent and treat cardiovascular disease. Kaiso, a zinc finger and BTB domain containing transcription factor, is key to embryonic development and cancer, but how Kaiso interacts with vascular endothelium is not fully understood. We report that Kaiso has an anti-apoptotic function in human umbilical vein endothelial cells (HUVECs) and human microvascular endothelial cells (HMEC-1s). Overexpression of Kaiso significantly increased cell viability and inhibited hydrogen peroxide-induced apoptosis. Furthermore, Kaiso increased expression of B-cell CLL/lymphoma 2 (BCL2) and reduced expression of BCL2-associated X protein (BAX) and BCL2-interacting killer (BIK) by differentially regulating gene promoter activity. Methylated DNA and specific Kaiso binding site (KBS) contributed to gene regulatory activity of Kaiso. In addition, p120ctn functioned cooperatively in Kaiso-mediated transcriptional regulation.

Salvianolic Acid B Inhibits High-Fat Diet-Induced Inflammation by Activating the Nrf2 Pathway

Salvianolic acid B (Sal B) is a major water-soluble bioactive component of Salvia miltiorrhiza, which is a traditional Chinese medicine. We investigated the ways in which Sal B affects high-fat diet (HFD)-induced immunological function disorder remission using a C57BL/6 mouse model. We gave groups of C57BL/6 mice a normal diet (Control), a normal diet supplemented with Sal B (Control + Sal B), a high-fat diet (HF), and a high-fat diet supplemented with Sal B (HF + Sal B) for 10 wk. Sal B supplementation decreased the body weight and plasma lipids, increased the fecal excretion of lipids, prevented the accumulation of chronic oxidative stress, and reversed the disproportionality of CD3⁺ CD4⁺ and CD3⁺ CD8⁺ T lymphocytes compared to HFD. We found an increase in IL-6 and TNF-α, while IL-10 decreased in plasma after the HFD and Sal B reversed the deregulation of the Thl/Th2 ratio. In addition, HFD-induced inflammation was stopped by Sal B through the downregulation of nuclear factor-κB (NF-κB), cyclooxygenase-2 (COX-2), and inducible NO synthesis (iNOS), and the upregulation of nuclear factor-erythroid 2-related factor 2 (Nrf2)-regulated genes. These findings demonstrated that Sal B could effectively attenuate inflammation by activating the Nrf2-mediated antioxidant defense system.

Salvianolic acid B attenuates lipopolysaccharide-induced acute lung injury in rats through inhibition of apoptosis, oxidative stress and inflammation

The present study was performed to assess the protective effect of salvianolic acid B on lipopolysaccharide (LPS)-induced acute lung injury (ALI). Sprague Dawley rats were injected with 100 µg/kg LPS through a 24-gauge catheter. One group of rats was pre-treated with salvianolic acid B (1 mg/ml; 20 ml/kg body weight) 1 h prior to LPS challenge, then 20 ml/kg salvianolic acid B every 2 days for 4 weeks thereafter. Salvianolic acid B attenuated LPS-induced increases in the lung wet/dry weight rate and lung tissue injury in ALI model rats. LPS-induced changes in the content of caspase-3, malondialdehyde, superoxide dismutase, catalase, glutathione peroxidase, tumor necrosis factor-α and interleukin-6 in ALI model rats were attenuated by treatment with salvianolic acid B. Furthermore, treatment with salvianolic acid B inhibited the protein expression of type I collagen I, endogenous transforming growth factor-β1 production and α-smooth muscle actin in ALI model rats. These findings indicated that salvianolic acid B attenuates LPS-induced ALI through inhibition of apoptosis, oxidative stress and inflammation in rats and therefore exertsa protective effect against ALI.

Daphnetin-mediated Nrf2 antioxidant signaling pathways ameliorate tert-butyl hydroperoxide (t-BHP)-induced mitochondrial dysfunction and cell death

Daphnetin (Daph), a natural coumarin derivative isolated from plants of the Genus Daphne, possesses abundant biological activities, such as anti-inflammatory, antioxidant and anticancer properties. In the present study, we focused on investigating the protective effect of Daph against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage, mitochondrial dysfunction and the involvement of underlying molecular mechanisms. Our findings indicated that Daph effectively inhibited t-BHP-stimulated cytotoxicity, cell apoptosis, and mitochondrial dysfunction, which are associated with suppressed reactive oxygen species (ROS) generation, decreased malondialdehyde (MDA) formation, increased superoxide dismutase (SOD) levels and glutathione (GSH)/GSSG (oxidized GSH) ratio. Further investigation indicated that Daph significantly suppressed cytochrome c release and NLRP3 inflammasome activation and modulated apoptosis-related protein Bcl-2, Bax, and caspase-3 expression. Moreover, Daph dramatically induced the expression of the glutamate-cysteine ligase modifier (GCLM) subunit and the glutamate-cysteine ligase catalytic (GCLC) subunit, heme oxygenase-1 (HO-1), and NAD (P) H: quinone oxidoreductase (NQO1), which is largely dependent on upregulating the nuclear factor-erythroid 2-related factor 2 (Nrf2) nuclear translocation, reducing the Keap1 protein expression, and strengthening the antioxidant response element (ARE) promoter activity. Additionally, Daph remarkably activated a c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) phosphorylation, but ERK and JNK inhibitor pretreatment exhibited an evident decrease of the level of Daph-enhanced Nrf2 nuclear translocation. Furthermore, Daph exposure suppressed t-BHP-induced cytotoxicity and ROS overproduction, which are mostly blocked in Nrf2 knockout RAW 264.7 cells and peritoneal macrophages. Accordingly, Daph exhibited protective roles against t-BHP-triggered oxidative damage and mitochondrial dysfunction by the upregulation of Nrf2 antioxidant signaling pathways, which may be involved in the activation of JNK and ERK.

Research Progress on Signaling Pathway-Associated Oxidative Stress in Endothelial Cells

Studying the mechanisms of oxidative stress in endothelial cells is vital to the discovery of novel drugs for the treatment of cardiovascular disease. This article reviews the progress within the field of the role of oxidative responses in the physiology and growth of endothelial cells and emphasizes the effects of several main signal pathways involved in the oxidative stress of endothelial cells. Herein, we aim to provide scientific direction that can serve as a basis for researchers specializing in the signaling pathway of oxidative stress.

Salvianolic Acid B Alleviates Heart Failure by Inactivating ERK1/2/GATA4 Signaling Pathway after Pressure Overload in Mice

BACKGROUND

Heart failure(HF) is a dangerous disease that affects millions of patients. Radix Salvia is widely used in Chinese clinics to treat heart diseases. Salvianolic acid B(SalB) is the major active component of Radix Salvia. This study investigated the mechanisms of action and effects of SalB on HF in an experimental mouse model of HF.

METHODS

We created a mouse model of HF by inducing pressure overload with transverse aortic constriction(TAC) surgery for 2 weeks and compared among 4 study groups: SHAM group (n = 10), TAC group (n = 9), TAC+MET group (metprolol, positive drug treatment, n = 9) and TAC+SalB group (SalB, 240 mg•kg-1•day-1, n = 9). Echocardiography was used to evaluate the dynamic changes in cardiac structure and function in vivo. Plasma brain natriuretic peptide (BNP) concentration was detected by Elisa method. In addition, H9C2 rat cardiomyocytes were cultured and Western blot were implemented to evaluate the phosphorylation of ERK1/2, AKT, and protein expression of GATA4.

RESULTS

SalB significantly inhibited the phosphorylation of Thr202/Tyr204 sites of ERK1/2, but not Ser473 site of AKT, subsequently inhibited protein expression of GATA4 and plasma BNP(P < 0.001), and then inhibited HF at 2 weeks after TAC surgery.

CONCLUSIONS

Our data provide a mechanism of inactivating the ERK1/2/GATA4 signaling pathway for SalB inhibition of the TAC-induced HF.

Chitosan oligosaccharide affects antioxidant defense capacity and placental amino acids transport of sows

BACKGROUND

Chitosan oligosaccharide (COS) is widely consumed as a functional food due to its multiple health effects, but few studies about COS supplement on placental antioxidant and nutrition transport capacity were reported. Taken pregnant sow as a model, we aimed to investigate the effects of dietary COS supplementation during late gestation on placental amino acids transport and antioxidant defense capacity of sows. From day (d) 85 of gestation to parturition, sixteen pregnant sows were divided into a control group (basal diet without COS supplementation) and a COS group (30 mg COS/kg basal diet). Plasma sample of sow was collected on d 110 of gestation, and placenta tissue was obtained during parturition. Then plasma antioxidant enzyme's activities, the relative level of oxidant stress related genes, amino acids transport related genes and mTOR pathway molecules in placenta were determined.

RESULTS

Results showed that maternal dietary supplementation with COS increased (P < 0.05) plasma total SOD, caused a downtrend in plasma MDA (0.05 < P < 0.10) on d 110 of gestation. Interestingly, the mRNA expression of some antioxidant genes in the placenta were increased (P < 0.05) and pro-inflammatory cytokines were reduced (P < 0.05) by COS supplement, whereas no significant difference was observed in the activities of placental total SOD and CAT between two groups. Additionally, further study demonstrated that COS feeding stimulated mTOR signaling pathway, increased amino acids transporters expression in placenta.

CONCLUSIONS

These observations suggested that COS supplement in sow's diet during late gestation enhanced antioxidant defense capacity of sows, promoted placental amino acids transport, which may contribute to the health of sows and development of fetus during gestation.

Therapeutic Strategies for Oxidative Stress-Related Cardiovascular Diseases: Removal of Excess Reactive Oxygen Species in Adult Stem Cells

Accumulating evidence indicates that acute and chronic uncontrolled overproduction of oxidative stress-related factors including reactive oxygen species (ROS) causes cardiovascular diseases (CVDs), atherosclerosis, and diabetes. Moreover ROS mediate various signaling pathways underlying vascular inflammation in ischemic tissues. With respect to stem cell-based therapy, several studies clearly indicate that modulating antioxidant production at cellular levels enhances stem/progenitor cell functionalities, including proliferation, long-term survival in ischemic tissues, and complete differentiation of transplanted cells into mature vascular cells. Recently emerging therapeutic strategies involving adult stem cells, including endothelial progenitor cells (EPCs), for treating ischemic CVDs have highlighted the need to control intracellular ROS production, because it critically affects the replicative senescence of ex vivo expanded therapeutic cells. Better understanding of the complexity of cellular ROS in stem cell biology might improve cell survival in ischemic tissues and enhance the regenerative potentials of transplanted stem/progenitor cells. In this review, we will discuss the nature and sources of ROS, drug-based therapeutic strategies for scavenging ROS, and EPC based therapeutic strategies for treating oxidative stress-related CVDs. Furthermore, we will discuss whether primed EPCs pretreated with natural ROS-scavenging compounds are crucial and promising therapeutic strategies for vascular repair.

Salvianolic acid B stimulates osteogenesis in dexamethasone-treated zebrafish larvae

AIM

Our previous studies show that salvianolic acid B (Sal B) promotes osteoblast differentiation and matrix mineralization. In this study, we evaluated the protective effects of Sal B on the osteogenesis in dexamethasone (Dex)-treated larval zebrafish, and elucidated the underlying mechanisms.

METHODS

At 3 d post fertilization, wild-type AB zebrafish larvae or bone transgenic tg (sp7:egfp) zebrafish larvae were exposed to Sal B, Dex, or a mixture of Dex+Sal B for 6 d. Bone mineralization in AB strain larval zebrafish was assessed with alizarin red staining, and osteoblast differentiation in tg (sp7:egfp) larval zebrafish was examined with fluorescence scanning. The expression of osteoblast-specific genes in the larvae was detected using qRT-PCR assay. The levels of oxidative stress markers (ROS and MDA) in the larvae were also measured.

RESULTS

Exposure to Dex (5-20 μmol/L) dose-dependently decreased the bone mineralization area and integral optical density (IOD) in wild-type AB zebrafish larvae and the osteoblast fluorescence area and IOD in tg (sp7:egfp) zebrafish larvae. Exposure to Dex (10 μmol/L) significantly reduced the expression of osteoblast-specific genes, including runx2a, osteocalcin (OC), alkaline phosphatase (ALP) and osterix (sp7), and increased the accumulation of ROS and MDA in the larvae. Co-exposure to Sal B (0.2-2 μmol/L) dose-dependently increased the bone mineralization area and IOD in AB zebafish larvae and osteoblast fluorescence in tg (sp7:egfp) zebrafish larvae. Co-exposure to Sal B (2 μmol/L) significantly attenuated deleterious alterations in bony tissue and oxidative stress in both Dex-treated AB zebafish larvae and tg (sp7:egfp) zebrafish larvae.

CONCLUSION

Sal B stimulates bone formation and rescues GC-caused inhibition on osteogenesis in larval zebrafish by counteracting oxidative stress and increasing the expression of osteoblast-specific genes. Thus, Sal B may have protective effects on bone loss trigged by GC.

Salvianolic acid B protects against paraquat-induced pulmonary injury by mediating Nrf2/Nox4 redox balance and TGF-β1/Smad3 signaling

The present study was aimed at exploring the protective effects of Salvianolic acid B (SalB) against paraquat (PQ)-induced lung injury in mice. Lung fibrotic injuries were induced in mice by a single intragastrical administration of 300mg/kg PQ, then the mice were administrated with 200mg/kg, 400mg/kg SalB, 100mg/kg vitamin C (Vit C) and dexamethasone (DXM) for 14days. PQ-triggered structure distortion, collagen overproduction, excessive inflammatory infiltration, pro-inflammatory cytokine release, and oxidative stress damages in lung tissues and mortality of mice were attenuated by SalB in a dose-dependent manner. Furthermore, SalB was noted to enhance the expression and nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and reduce expression of the reactive oxygen species-generating enzyme Nox4 [NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase-4]. SalB also inhibited the increasing expression of transforming growth factor (TGF)-β1 and the phosphorylation of its downstream target Smad3 which were enhanced by PQ. These results suggest that SalB may exert protective effects against PQ-induced lung injury and pulmonary fibrosis. Its mechanisms involve the mediation of Nrf2/Nox4 redox balance and TGF-β1/Smad3 signaling.

Production of rosmarinic acid and salvianolic acid B from callus culture of Salvia miltiorrhiza with cytotoxicity towards acute lymphoblastic leukemia cells

Salvia miltiorrhiza (SM) Bunge is one of the widely-used Chinese medicinal herbs. In this study, the chemical constituents and anticancer potential of SM stems and leaves were examined with those of respective callus cultures. The callus culture for stem and leaf explants was initiated in modified Murashige and Skoog (MS) medium. Active constituents of respective extracts were analyzed by high performance liquid chromatography coupled with DAD and MS (HPLC-DAD-MS). Rosmarinic acid (RA) and salvianolic acid B (Sal B) were determined to be the main phenolic compounds. Quantitative analyses revealed that callus stem extracts produced higher amount of RA and Sal B (stem RA: 1.27±0.38%; stem Sal B: 0.87±0.20%) than callus leaf did (leaf RA: 0.28±0.02%; leaf Sal B: 0.07±0.03%). Stem and leaf callus extracts exerted cytotoxic effects towards CCRF-CEM cells (stem: 13.1±0.90 μg/ml; leaf: 18.1±0.33 μg/ml). As expected, stem extract with higher amount of RA and Sal B showed lower IC50 value than leaf extract. These findings suggest the possibility to isolate bioactive constituents with anticancer properties from in vitro callus cultures of stems and leaves of SM.

Salvianolic Acid B Prevents Iodinated Contrast Media-Induced Acute Renal Injury in Rats via the PI3K/Akt/Nrf2 Pathway

Contrast-induced acute renal injury (CI-AKI) has become a common cause of hospital-acquired renal failure. However, the development of prophylaxis strategies and approved therapies for CI-AKI is limited. Salvianolic acid B (SB) can treat cardiovascular-related diseases. The aim of the present study was to assess the effect of SB on prevention of CI-AKI and explore its underlying mechanisms. We examined its effectiveness of preventing renal injury in a novel CI-AKI rat model. Compared with saline, intravenous SB pretreatment significantly attenuated elevations in serum creatinine and the histological changes of renal tubular injuries, reduced the number of apoptosis-positive tubular cells, activated Nrf2, and lowered the levels of renal oxidative stress induced by iodinated contrast media. The above renoprotection of SB was abolished by the PI3K inhibitor (wortmannin). In HK-2 cells, SB activated Nrf2 and decreased the levels of oxidative stress induced by hydrogen peroxide and subsequently improved cell viability. The above cytoprotection of SB was blocked by the PI3K inhibitor (wortmannin) or siNrf2. Thus, our results demonstrate that, due to its antioxidant properties, SB has the potential to effectively prevent CI-AKI via the PI3K/Akt/Nrf2 pathway.

Angelica archangelia Prevented Collagen Degradation by Blocking Production of Matrix Metalloproteinases in UVB-exposed Dermal Fibroblasts

Angelica archangelia (AA), a traditional herb, has attracted attention as an agent with potential for use in the prevention of chronic skin diseases. This study examined the photoprotective effects of AA on the inhibition of matrix metalloproteinases (MMPs) and collagen degradation in UVB-irradiated normal human dermal fibroblasts. Our results showed that AA markedly blocked collagen degradation by restraining the production of MMPs in UVB-exposed fibroblasts. We also investigated the underlying mechanism behind the effects of AA. AA attenuated UVB-triggered interleukin-6 (IL-6) and promoted the expression of transforming growth factor β1. Application of AA extract (10, 100 μg mL(-1) ) significantly diminished UVB-induced extracellular signal-regulated kinase and Jun-N-terminal kinase phosphorylation, which consequently reduced phosphorylated c-Fos and c-Jun. Our results indicated that AA inhibited the UVB-induced expression of MMPs by inhibiting mitogen-activated protein kinase signaling pathways and activator protein-1 activation. Our results suggest that AA is a promising botanical agent for use against skin photoaging.

Salvianolate Protects Hepatocytes from Oxidative Stress by Attenuating Mitochondrial Injury

Salvianolate is widely used to treat angiocardiopathy in clinic in China, but its application in liver diseases remains unclear. Our study aims to investigate the effect of Salvianolate on rat hepatic injury by protecting hepatocyte mitochondria. To evaluate the effects of Salvianolate on injured hepatocytes, alpha mouse liver 12 (AML-12) cells were induced with hydrogen peroxide (H₂O₂) and treated with Salvianolate. Cell viability and MitoTracker Green for mitochondria and 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazole-carbocyanide iodine (JC-1) levels and cytochrome C (Cyto-C) expressions were detected in vitro. To identify the effect of Salvianolate on protecting against mitochondria injury, male Wistar rats were injected with carbon tetrachloride (CCl₄) and treated with Salvianolate (40 mg·kg⁻¹). Serum liver function, parameters for peroxidative damage, hematoxylin and eosin (H&E) staining, and transmission electron microscope (TEM) of hepatocyte mitochondria were assayed. Our results showed that Salvianolate effectively protected hepatocytes, increased mitochondria vitality, and decreased Cyto-C expressions in vitro. Besides, Salvianolate alleviated the liver function, attenuated the indicators of peroxidation, and relieved the mitochondria injury in vivo. In conclusion, Salvianolate is effective in protecting hepatocytes from injury in vitro and in vivo, and the mechanism might be related to its protective effect on hepatocyte mitochondria against oxidative stress.