Targeting PKM2 signaling cascade with salvianic acid A normalizes tumor blood vessels to facilitate chemotherapeutic drug delivery.

Aberrant tumor blood vessels are prone to propel the malignant progression of tumors, and targeting abnormal metabolism of tumor endothelial cells emerges as a promising option to achieve vascular normalization and antagonize tumor progression. Herein, we demonstrated that salvianic acid A (SAA) played a pivotal role in contributing to vascular normalization in the tumor-bearing mice, thereby improving delivery and effectiveness of the chemotherapeutic agent. SAA was capable of inhibiting glycolysis and strengthening endothelial junctions in the human umbilical vein endothelial cells (HUVECs) exposed to hypoxia. Mechanistically, SAA was inclined to directly bind to the glycolytic enzyme PKM2, leading to a dramatic decrease in endothelial glycolysis. More importantly, SAA improved the endothelial integrity via activating the ß-Catenin/Claudin-5 signaling axis in a PKM2-dependent manner. Our findings suggest that SAA may serve as a potent agent for inducing tumor vascular normalization.

Salvianic acid A sodium facilitates cardiac microvascular endothelial cell proliferation by enhancing the hypoxia-inducible factor-1 alpha/vascular endothelial growth factor signalling pathway post-myocardial infarction.

Cardiac microvascular endothelial cells (CMECs) are important cells surrounding the cardiomyocytes in the heart that maintain microenvironment homeostasis. Salvianic acid A sodium (SAAS) has been reported to prevent myocardial infarction (MI) injury. However, the role of SAAS on CMEC proliferation remains unclear. CEMCs exposed to oxygen glucose deprivation (OGD) were used to explore the angiogenic abilities of SAAS. In vivo, C57BL/6 mice were divided into three groups: sham, MI and SAAS + MI groups. Compared to OGD group, SAAS led to a reduction in the apoptotic rate and an increase of the proliferation in vitro. Additionally, SAAS increased the protein levels of Bcl2, HIF-1α and vascular endothelial growth factor (VEGF) with the reduction of Bax. In terms of the specific mechanisms, SAAS might inhibit HIF-1α ubiquitination and enhance the HIF-1α/VEGF signalling pathway to increase CMEC proliferation. Furthermore, SAAS increased the density of vessels, inhibited myocardial fibrosis and improved cardiac dysfunction in vivo. The present study has revealed that SAAS could potentially be used as an active substance to facilitate CMEC proliferation post-MI.

Enhanced Brain Targeting Delivery of Salvianic Acid Using Borneol as a Promoter of Blood/Brain Transport and Regulator of P-gp.

BACKGROUND: Borneol can enhance the blood-brain barrier (BBB) permeability of some drugs and suppress the efflux transport of P-glycoprotein (P-gp), which will contribute to the brain delivery of salvianic acid A (SAA). OBJECTIVE: The study aimed to develop an approach to improve the brain targeting delivery of SAA with the aid of borneol. MATERIALS AND METHODS: "Borneol" was involved in SAA via esterified prodrug SAA borneol ester (SBE) and combined administration (SAA-borneol, SAA-B). Subsequently, the blood-brain transport of SAA through brain/blood distribution and P-gp regulation via expression and function assay were investigated in rats. RESULTS: The SBE and SAA-B-treated group received a three-fold brain concentration and longer t1/2 and retention period of active SAA than that of SAA alone (20.18/13.82 min vs. 6.48 min; 18.30/17.42 min vs. 11.46 min). In addition, blood to brain transport of active SAA in SBE was altered in comparison to that of SAA-B, ultimately resulting in a better drug targeting index (9.93 vs. 3.63). Further studies revealed that SBE-induced downregulation of P-gp expression occurred at the later stage of administration (60 min, P < 0.01), but SBE always showed a more powerful drug transport activity across BBB represented by Kp value of rhodamine 123 than SAA-B (30, 60 min, P < 0.05). CONCLUSION: The comparative results indicate that SBE exhibits prominent efficiency on SAA's targeting delivery through improved blood/brain metabolic properties and sustained inhibitory effect of "borneol" on P-gp efflux. Therefore, prodrug modification can be applied as a more effective approach for brain delivery of SAA.

Dangui Huoxue Preparation (DHP) Ameliorates Skin Fibrosis, Inflammation, and Vasculopathy in the Bleomycin-Induced Murine Model of Systemic Sclerosis.

Systemic sclerosis (SSc) is an immune-mediated rheumatic disease that is characterized by fibrosis of the skin and internal organs and vasculopathy with poor prognosis. Dangui Huoxue Preparation (DHP) is a clinically effective traditional Chinese herbal formula for the treatment of SSc in the hospital. This study aims to investigate the therapeutic effects and underlying molecular mechanisms of DHP in the treatment of SSc. SSc mice models are induced by bleomycin (BLM). Tissues of DHP group, normal control group, and positive control drug Sanqi Tongshu Capsule (STC) group are collected for inflammation, fibrosis, and vasculopathy. Also, the human dermal fibroblasts (HDF) stimulated with TGF-ß1 are analyzed for in vitro study. The expression levels of MCP-1, IFN-γ, IL-1ß, IL-10, Fizz1, iNOS, and IL12p40, and the mRNA levels of Col1a1, Col1a2, Col3a1, and Col5a1 are significantly decreased in all DHP groups and STC group compare with those in the BLM group. The main drug of DHP inhibits the proliferation and migration of HDF, reduces Ctgf, Itgb3, Itgb5 expression, and also inhibits the Smad3 pathway. In conclusion, DHP can ameliorate SSc skin inflammation, fibrosis, and vasculopathy, possibly suppressing the TGF-ß1/Smad3 signaling pathway through extracellular and intracellular mechanisms.

Protective effects of Salvianic acid A against multiple-organ ischemia-reperfusion injury: a review.

Ischemia-reperfusion (I/R) injury refers to a new injury caused by reperfusion after the restoration of ischemic tissue or organ blood supply. Salvianic acid A (danshensu) is a primary active ingredient extracted from Salvia miltiorrhiza. It has a protective function against I/R injury in the cardiovascular system, brain, liver, kidney, gastrointestinal tract, and other organs. This article reviews evidence of the protective effects of Salvianic acid A and its potential mechanisms of action in organ I/R injury protection. The aim of this review is to investigate the role of Salvianic acid A in the treatment of I/R injury, providing a reference resource that could facilitate subsequent studies.

Protective benefits of salvianic acid A against retinal iron overload by inhibition of ferroptosis.

BACKGROUND: Both the accumulation of reactive oxygen species (ROS) and iron overload are significant variables that enhance the incidence of photoreceptor cell death and retinal degeneration. The discovery of ferroptosis, which is characterized by iron-dependent lipid peroxidation, has led to a new perspective on how retinal degeneration develops. As a natural phenolic acid, salvianic acid A (SAA) from Salvia miltiorrhiza has promise in treating eye diseases. The purpose of this research was to learn more about SAA and its function in the development of iron-overload-induced retinal degeneration. METHODS: Models of iron overload in Kunming mice and the murine photoreceptor cell line 661 W were established, then the protective and antiferroptotic properties of SAA were assessed in vivo and in vitro. RESULTS: Biochemical and histopathological findings on the retina confirmed that SAA successfully alleviated retinal injury. In photoreceptor cells, iron overload caused cell death, mitochondrial dysfunction, ROS generation, and iron deposition. Salvianic acid A relieved lipid peroxidation and decreased iron accumulation by modulating Acyl-CoA synthetase long-chain family member 4, glutathione peroxidase 4, solute carrier family 7 member 11, and iron-metabolism-related proteins. The mitochondrial morphology suggests that the retinal protective effect of SAA is mediated via antiferroptotic action. CONCLUSION: Ferroptosis plays an important role in the pathogenesis of iron-overload-induced retinal degeneration. New roles of SAA in ferroptosis prevention via iron deposit inhibition, lipid peroxidation inhibition, and mitochondrial dysfunction reduction, were identified.

Efficient production of salvianic acid A from L-dihydroxyphenylalanine through a tri-enzyme cascade.

Salvianic acid A (SAA), used for treating cardiovascular and cerebrovascular diseases, possesses several pharmacological properties. However, the current methods for the enzymatic synthesis of SAA show low efficiency. Here, we constructed a three-enzyme cascade pathway in Escherichia coli BL21 (DE3) to produce SAA from L-dihydroxyphenylalanine (L-DOPA). The phenylpyruvate reductase (LaPPR) from Lactobacillus sp. CGMCC 9967 is a rate-limiting enzyme in this process. Therefore, we employed a mechanism-guided protein engineering strategy to shorten the transfer distances of protons and hydrides, generating an optimal LaPPR mutant, LaPPRMu2 (H89M/H143D/P256C), with a 2.8-fold increase in specific activity and 9.3-time increase in kcat/Km value compared to that of the wild type. Introduction of the mutant LaPPRMu2 into the cascade pathway and the optimization of enzyme levels and transformation conditions allowed the obtainment of the highest SAA titer (82.6 g L-1) ever reported in vivo, good conversion rate (91.3%), excellent ee value (99%) and the highest productivity (6.9 g L-1 h-1) from 90 g L-1 L-DOPA in 12 h. This successful strategy provides a potential new method for the industrial production of SAA.

Production of Salvianic Acid A from l-DOPA via Biocatalytic Cascade Reactions.

Salvianic acid A (SAA), as the main bioactive component of the traditional Chinese herb Salvia miltiorrhiza, has important application value in the treatment of cardiovascular diseases. In this study, a two-step bioprocess for the preparation of SAA from l-DOPA was developed. In the first step, l-DOPA was transformed to 3,4-dihydroxyphenylalanine (DHPPA) using engineered Escherichia coli cells expressing membrane-bound L-amino acid deaminase from Proteus vulgaris. After that, the unpurified DHPPA was directly converted into SAA by permeabilized recombinant E. coli cells co-expressing d-lactate dehydrogenase from Pediococcus acidilactici and formate dehydrogenase from Mycobacterium vaccae N10. Under optimized conditions, 48.3 mM of SAA could be prepared from 50 mM of l-DOPA, with a yield of 96.6%. Therefore, the bioprocess developed here was not only environmentally friendly, but also exhibited excellent production efficiency and, thus, is promising for industrial SAA production.

Quantitative analysis of effects of salvianic acid a combined with hydroxy safflower yellow a on rat endothelial cells after hypoxic injury using the combination index method

Abstract Cerebrovascular disease is the second most serious disease in the world. It has the features of high morbidity, high mortality and recurrence rate. Numerous research on the compatibility of Chinese medicine with effective ingredients of cerebral ischemia has been made during the past decades. The purpose of this study is to quantitatively analyze the combined pharmacological effect of effective ingredients in Danshen and Honghua (Dan Hong) on rat microvascular endothelial cells after gradually oxygen-glucose deprivation. The experimental concentration range for the compatibility of two effective ingredients were determined in the preliminary experiments by Cell Counting kit-8 (CCK-8) method. Drugs were added to rat brain microvascular endothelial cells at a non-toxic dose level. After that, the cells were cultured for 12 h, and placed in a hypoxic environment. Finally, the cell survival rate was used as a measure of drug effect. In order to determine synergism or antagonism, the combination index (CI)-isobologram method was performed to analyze the data from the experiments. Based on this theory, the potencies of each drug and the shapes of their does-effect curves are both taken into account. The results show that the synergism or the antagonism between two effective ingredients compatibility change with different proportion and dosage. Furthermore, it can be seen from the results of these experiments that when these drugs are used in combination, the dosage required to achieve the same therapeutic effects is greatly reduced compared with the case of single one. It is worth mentioning that our experiments also prove that the median-effect equation and the CI method can be applied in the field of traditional Chinese medicine.

Highly sensitive detection of salvianic acid a drug by a novel electrochemical sensor based on HKUST-1 loaded on three-dimensional graphene-MWCNT composite.

HKUST-1, a kind of metal-organic framework (MOF) composed by Cu2+ and trimesic acid, loaded on reduced graphene oxide and multi-walled carbon nanotubes nanocomposite [HKUST-1 @ (RGO-MWCNT)] was successfully synthesized by a facile and simple route. Then, a highly sensitive non-enzymatic salvianic acid A (SAA) electrochemical sensor was fabricated by modifying HKUST-1 @ (RGO-MWCNT) on a glassy carbon electrode, taking full advantage of the synergistic effect between the redox catalytic capacity of Cu2+ and the electrical conductivity of carbon materials. The sensor showed a low limit of detection of 0.081 µM, limit of quantitation of 0.27 µM, high sensitivity of 509.6 µA/mM and a good relationship between reduction peak current and concentration of SAA from 2 to 4600 µM. Meanwhile, the sensor had the advantages of repeatability and stability. Finally, it was used to detect SAA in real samples with noteworthy electroanalytical performance. In short, the sensor has considerable potential for the electroanalysis of SAA. Moreover, the study provides a promising composite of MOF and carbon materials with potential application in the analysis of effective components of herbaceous medicinal plants.

Ameliorative effects and mechanisms of salvianic acid A on retinal iron overload in vivo and in vitro.

Excessive iron can be accumulated in the retina and lead to retinal iron overload. Salvianic acid A (SAA) has a variety of pharmacologic effects, but there is only a limited understanding of its benefits for retinal iron overload. The aim of this study was to examine the protective effects and latent mechanisms of SAA on retinal iron overload. SAA reduced iron in the serum and retina, attenuated pathophysiological changes, and reduced retinal iron deposition in the retinas of iron-overloaded mice. It also reduced intracellular iron in ARPE-19 cells by regulating iron-handling proteins and chelating with iron. It also significantly inhibited cellular oxidative and inflammatory damage by increasing the nuclear translocation of nuclear erythroid 2-related factor 2 (Nrf2) while decreasing nuclear factor-kappa B (NF-κB), protecting the ARPE-19 cells from apoptosis by suppressing the Bax/Bcl-2 ratio, cytochrome c release, caspase activation, and poly ADP-ribose polymerase cleavage. The ability of SAA to inhibit apoptosis, increase nuclear Nrf2 expression, and decrease nuclear NF-κB expression was further confirmed in the retinas of iron-overloaded mice. This study demonstrates that SAA shows significant protective effects against retinal iron overload; its mechanisms might be associated with iron chelation; regulation of iron-handling proteins; and inhibition of oxidative stress, inflammation and apoptosis.

Salvia miltiorrhiza solution and its active compounds ameliorate human granulosa cell damage induced by H2O2.

The dried roots or rhizomes of Salvia miltiorrhiza Bge are commonly used in Chinese medicine to promote blood circulation and regulate menstruation. Salvianic acid A and salvianolic acid B are the main active water-soluble compounds in Salvia miltiorrhiza solution. The present study investigated the protective effect of Salvia miltiorrhiza solution and its active compounds in H2O2-induced cell damage of the human ovarian granulosa tumor cell line (KGN) in vitro, as well as its underlying mechanism. Cell viability was detected using a Cell Counting Kit-8 assay. In addition, the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH) and tumor necrosis factor-α (TNF-α) were measured. Western blotting was performed to detect the protein expression of cleaved caspase-3 and caspase-9. Furthermore, immunocytochemistry was used to detect the expression of TNF-α. It was demonstrated that Salvia miltiorrhiza solution, salvianic acid A and salvianolic acid B did not affect the viability of KGN cells. Additionally, salvianic acid A and salvianolic acid B significantly reduced the H2O2-induced increased MDA levels, and reversed the H2O2-induced suppression of SOD and GSH activities in KGN cells (P<0.05). Treatment with Salvia miltiorrhiza solution, salvianic acid A and salvianolic acid B significantly reduced the overexpression of cleaved caspase-3, cleaved caspase-9 and TNF-α compared with the H2O2-treated group (P<0.05). Therefore, the present results indicated that Salvia miltiorrhiza solution and its main water-soluble compounds, salvianic acid A and salvianolic acid B, ameliorated KGN cell damage induced by H2O2.

Bone-Targeting Liposome-Encapsulated Salvianic Acid A Improves Nonunion Healing Through the Regulation of HDAC3-Mediated Endochondral Ossification.

AIM: Nonunion is a major complication in fracture repair and remains a challenge in orthopaedics and trauma surgery. In this study, we aimed to evaluate the effectiveness of treatment of nonunion with a large radial defect using a bone-targeting liposome-encapsulated salvianic acid A (SAA-BTL)-incorporated collagen sponge and further elucidate whether the effects were closely related to histone deacetylase 3 (HDAC 3)-mediated endochondral ossification in nonunion healing process. METHODS: Fifteen New Zealand female rabbits were randomly divided into three groups. Segmental radius critical size defects (15 mm) were created via surgery on both the forelimbs of the rabbits. The SAA-BTL/SAA/saline-incorporated collagen sponges were implanted into the defects in the three groups, respectively, for four weeks of treatment. X-ray imaging, micro-computed tomography (CT) analysis, histology, and immunofluorescence analysis (HDAC3, collagen II, VEGFA, and osteocalcin) were performed to determine the effects of the treatments. In addition, a short interfering RNA was applied to induce HDAC3 knockdown in the chondrogenic cell line ATDC5 to investigate the roles of HDAC3 and SAA intervention in endochondral ossification in nonunion healing. RESULTS: X-ray imaging and micro-CT results revealed that SAA-BTL-incorporated collagen sponges significantly stimulated bone formation in the nonunion defect rabbit model. Furthermore, immunofluorescence double staining and histology analysis confirmed that SAA-BTL significantly increased the expression of P-HDAC3, collagen II, RUNX2, VEGFA, and osteocalcin in vivo; accelerated endochondral ossification turnover from cartilage to bone; and promoted long bone healing of nonunion defects. ATDC5 cells knocked down for HDAC3 showed significantly decreased expression of HDAC3, which resulted in reduced expression of chondrogenesis, osteogenesis, and angiogenesis biomarker genes (Sox9, Col10a1, VEGFA, RUNX2, and Col1a1), and increased expression of extracellular matrix degradation marker (MMP13). SAA treatment reversed these effects in the HDAC3 knockdown cell model. CONCLUSION: SAA-BTL can improve nonunion healing through the regulation of HDAC3-mediated endochondral ossification.

Danshen formula granule and salvianic acid A alleviate ethanol-induced neurotoxicity.

As a direct neurotoxin, ethanol exposure is associated with nerve damage and dysfunction of central nervous system (CNS) and induced obvious neurotoxicity by increasing the reactive oxygen species (ROS) production, activation of endogenous apoptotic as well as necrotic signals, and other molecular mechanisms. The previous studies had demonstrated that natural herbal medicine offers protective effectiveness on ethanol-induced nerve cell damage. Danshen and its extracts have been known to have an antioxidant property and neuroprotective effects. However, the protective effects of Danshen formula granule and salvianic acid A on ethanol-induced neurotoxicity remain unknown. In this study, we found that the Danshen formula granule and salvianic acid A significantly inhibited the ethanol-induced cell death, blocked LDH release, and reduced dendritic spine loss. Furthermore, the intracellular ROS, MDA production, and ethanol-induced apoptosis were significantly ameliorated with Danshen formula granule and salvianic acid A pretreatment by increasing the antioxidant enzymatic activity of CAT, SOD and GSH-Px, and inhibiting apoptotic pathways. In addition, Danshen formula granule and salvianic acid A pretreatment obviously inhibit the apoptotic pathways by regulating the protein expression of Bcl-2, Bax, and Caspase-3. In conclusion, our data demonstrated that the Danshen formula granule and salvianic acid A provide a significantly protective effectiveness against ethanol-induced neurotoxicity, which might be a potential therapeutic drug for ethanol-induced neurological disorders.

Supplementation of salvianic acid A to boar semen extender to improve seminal quality and antioxidant capacity.

The purpose of this test was to investigate the effect of salvianic acid A (SAA, CAS No. 76822-21-4) on the quality of boar semen during liquid storage at 17°C. The effects of different concentrations of SAA on semen quality and antioxidant capacity were analyzed. Boar semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations (0, 15, 30, 45, 60, 75 µM of SAA). During the storage period, sperm activity was measured every 24 hr, and plasma membrane integrity, acrosome integrity, total antioxidant capacity (T-AOC), malondialdehyde (MDA) content, and catalase (CAT) activity were measured at 0, 1, 3, and 5 days. The results from our study suggest that different concentrations of SAA have different effects on semen preservation. Semen samples supplemented with SAA showed reduced effects of oxidative stress on sperm compared to the control samples. Supplementation of 30 µM of SAA significantly improved sperm motility, plasma membrane integrity, acrosome integrity, and antioxidant capacity. However, the addition of SAA to the extender was scarcely beneficial to the improvement of results of artificial insemination with boar semen after liquid preservation. Further studies are necessary in order to demonstrate that SAA has good effects on the liquid preservation of semen.

Cardioprotective mechanisms of salvianic acid A sodium in rats with myocardial infarction based on proteome and transcriptome analysis.

Ischemic heart diseases (IHDs) cause great morbidity and mortality worldwide, necessitating effective treatment. Salvianic acid A sodium (SAAS) is an active compound derived from the well-known herbal medicine Danshen, which has been widely used for clinical treatment of cardiovascular diseases in China. This study aimed to confirm the cardioprotective effects of SAAS in rats with myocardial infarction and to investigate the underlying molecular mechanisms based on proteome and transcriptome profiling of myocardial tissue. The results showed that SAAS effectively protected against myocardial injury and improved cardiac function. The differentially expressed proteins and genes included important structural molecules, receptors, transcription factors, and cofactors. Functional enrichment analysis indicated that SAAS participated in the regulation of actin cytoskeleton, phagosome, focal adhesion, tight junction, apoptosis, MAPK signaling, and Wnt signaling pathways, which are closely related to cardiovascular diseases. SAAS may exert its cardioprotective effect by targeting multiple pathways at both the proteome and transcriptome levels. This study has provided not only new insights into the pathogenesis of myocardial infarction but also a road map of the cardioprotective molecular mechanisms of SAAS, which may provide pharmacological evidence to aid in its clinical application.

The attenuation of HIV-1 Tat-induced neurotoxicity by Salvianic acid A and Danshen granule.

The neurotoxicity of HIV-1 Tat protein contributes significantly to the pathogenesis of HAND, and hence the attractive therapeutic strategies focusing on Tat-induced neurotoxicity are warranted. Salvia miltiorrhiza have been known to antioxidant property and neuroprotective effects. The Danshen granule is the pharmaceutical dosage forms of Salvia miltiorrhiza and Salvianic acid A is an essential chemical constituent of Salvia miltiorrhiza. However, the protective effects of Salvianic acid A and Danshen granule on Tat-induced neurotoxicity remain unknown. Here, we found that Salvianic acid A and Danshen granule remarkable inhibited Tat-induced cell death, blocked LDH release and rescued dendritic spine loss. Furthermore, Salvianic acid A and Danshen granule significantly ameliorates Tat-induced intracellular ROS and MDA production, attenuates cell apoptosis. In addition, Salvianic acid A and Danshen granule pretreatment obviously increases antioxidant enzymatic activity of CAT, SOD and GSH-Px and inhibits apoptotic pathways. In conclusion, this study demonstrated that Salvianic acid A and Danshen granule provides substantial neuroprotection against Tat-induced neurotoxicity, which may be new therapeutic agent in Tat induced HAND or neurodegenerative diseases.

Potential mechanisms underlying the protective effects of salvianic acid A against atherosclerosis in vivo and vitro.

Salvianic acid A (SAA) is an active water-soluble constituent derived from Salvia miltiorrhiza Bge that is used extensively in the treatment of angiocardiopathy in China. However, few reports have investigated the therapeutic effect and the underlying mechanisms of SAA on atherosclerosis (AS). This study examines the protective mechanisms of SAA on AS in vivo and in vitro. SAA treatment (3 and 10 mg/kg/d) prevented the progression of atherosclerotic lesions and decreased 58.2% and 72.8% of the lipid deposition in the aorta of high fat-diet-induced AS rat. Notably, SAA treatment ameliorated serum lipid abnormalities by decreasing 20.4% and 33.8% of triglyceride, 26.1% and 32.7% of total cholesterol, 36.0% and 57.3% of low-density lipoprotein-cholesterol levels and increasing 183.4% and 337.5% of high-density lipoprotein-cholesterol level in the serum of AS rat (all P < 0.05). SAA treatment lowered pro-inflammatory mediators including interleukin-1ß, interleukin-6, tumor necrosis factor-α, intercellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) (all P < 0.05) by inhibiting the toll-like receptor 4/nuclear factor kappa B pathway. In addition, SAA treatment significantly decreased oxidative stress by increasing antioxidant enzymes activity, upregulating nuclear factor erythroid 2-related factor 2/heme oxygenase-1 pathway and downregulated expression of p47phox and p22phox (all P < 0.05) in vivo. Furthermore, SAA (10-5 and 3 × 10-5 M) suppressed oxidized low-density lipoprotein-induced expression of lectin-like oxidized low-density lipoprotein receptor-1, the phosphorylation of nuclear factor kappa B (p65), ICAM-1 and VCAM-1 (all P < 0.05) and inhibited NADPH oxidase subunit 4-mediated reactive oxygen species generation in human umbilical vein endothelial cells. The experimental data verify the protective role of SAA in AS and the underlying mechanisms are strongly associated with the inhibition of oxidative stress, inflammation, and amelioration of endothelial dysfunction.

Copper (II)-ploy-L-histidine functionalized multi walled carbon nanotubes as efficient mimetic enzyme for sensitive electrochemical detection of salvianic acid A.

In this work, carboxylated multi walled carbon nanotubes (CMWCNTs) were firstly prepared and functionalized with poly-L-histidine (PLH), which were then chelated with copper (II) ions to from the nanocomposites of Cu(II)-PLH-CMWCNTs. The nanocomposites could be exploited as an efficient mimic enzyme for sensitive electrochemical detection of salvianic acid A (SAA). Cu(II)-PLH-CMWCNTs owned good charge transfer property and excellent synergetic catalytic effect between the overoxidized imidazole groups and the copper redox-active units. Therefore, highly sensitive electrochemical response to SAA was achieved under optimum experimental conditions. A good linear relationship between differential pulse voltammetry (DPV) peak current and the SAA concentration was established in the range of 0.4-1000 µM. A low detection limit of 0.037 µM and a sensitivity of 0.27 µA µM-1 cm-2 were achieved. The developed biosensor also had advantages of good repeatability, stability and high selectivity, thus, it was successfully applied to the determination of SAA in real samples with satisfactory results, which may have great potential for further exploitation of electroanalysis applications.

Bone-targeting liposome formulation of Salvianic acid A accelerates the healing of delayed fracture Union in Mice.

Delayed fracture union is a significant clinical challenge in orthopedic practice. There are few non-surgical therapeutic options for this pathology. To address this challenge, we have developed a bone-targeting liposome (BTL) formulation of salvianic acid A (SAA), a potent bone anabolic agent, for improved treatment of delayed fracture union. Using pyrophosphorylated cholesterol as the targeting ligand, the liposome formulation (SAA-BTL) has demonstrated strong affinity to hydroxyapatite in vitro, and to bones in vivo. Locally administered SAA-BTL was found to significantly improve fracture callus formation and micro-architecture with accelerated mineralization rate in callus when compared to the dose equivalent SAA, non-targeting SAA liposome (SAA-NTL) or no treatment on a prednisone-induced delayed fracture union mouse model. Biomechanical analyses further validated the potent therapeutic efficacy of SAA-BTL. These results support SAA-BTL formulation, as a promising therapeutic candidate, to be further developed into an effective and safe clinical treatment for delayed bone fracture union.