Salvianolic Acid B
Ameliorates Neuronal Inflammation
A traditional Chinese medicine, Salvia miltiorrhiza has been widely used in Asian countries for the treatment of cardiovascular, cerebrovascular diseases and spinal cord injury. Currently, two major components extracted from the root of S. miltiorrhiza are Tanshinone IIA and Salvianolic acid B (Sal B).
In the United States, the incidence of SCI has been estimated to be about 40 cases per million population per year, and there are around 265,000 individuals living with SCIs at present with over 80% occurrence in males . The prevalence of SCI is approximately 60,000 per year in China according to a recent report .
Salvianolic acid B is a cell protective antioxidant and free radical scavenger being investigated for a variety of conditions from ischemic heart disorders to Alzheimer′s disease. Several mechanisms of action have been proposed including EGFR, PDGF and MMP-9 inhibition and inhibition of the TGF-β1/Smads and NF-κB signaling pathways. Salvianolic acid B acts as scavengers of reactive oxygen species, reduces the adherence of leukocytes to endothelial cells, inhibits matrix metalloproteinases and inflammation. It has cardioprotective effects as it reduces lipid peroxidation in damaged cardiac tissue and decreases the leakage of lactic acid dehydrogenase.
Salvianolic Acids for Injection (SAFI) Suppresses Inflammatory Responses in Activated Microglia to Attenuate Brain Damage in Focal Cerebral Ischemia.
Inflammatory reactions induced by microglia in the brain play crucial roles in ischemia/reperfusion (I/R) cerebral injuries. Microglia activation has been shown to be closely related to TLR4/NF-κB signal pathways. Salvianolic acids for injection (SAFI) have been used in clinical practice to treat ischemic stroke with reported neuroprotective effects; however, the underlying mechanisms are still uncertain.
OBJECTIVE AND METHODS:
First, we studied the effect of SAFI on inflammatory responses in LPS-stimulated BV-2 microglia. Then, to discover whether the beneficial in vitro effects of SAFI lead to in vivo therapeutic effects, an MCAO (Middle cerebral artery occlusion) rat model was further employed to elucidate the probable mechanism of SAFI in treating ischemic stroke. Rats in the SAFI group were given SAFI (23 or 46mg/kg) before I/R injury.
The results showed that SAFI treatment significantly decreased neuroinflammation and the infarction volume compared with the vehicle group. Activation of microglia cells was reduced, and TLR4/NF-κB signals, which were markedly inhibited by SAFI treatment in ischemic hemisphere, were accompanied by reduced expression and release of cytokines IL-1β and IL-6.
This study provides evidence that SAFI effectively protects the brain after cerebral ischemia, which may be caused by attenuating inflammation in microglia.
J Cell Mol Med. 2017 Feb 28. doi: 10.1111/jcmm.13104. [Epub ahead of print]
Salvianolic acid B regulates gene expression and promotes cell viability in chondrocytes.
Articular chondrocytes reside in lacunae distributed in cartilage responsible for the remodelling of the tissue with limited ability of damage repairing. The in vitro expanded chondrocytes enhanced by factors/agents to obtain large numbers of cells with strengthened phenotype are essential for successful repair of cartilage lesions by clinical cell implantation therapies. Because the salvianolic acid B (Sal B), a major hydrophilic therapeutic agent isolated from Salvia miltiorrhiza, has been widely used to treat diseases and able to stimulate activity of cells, this study examines the effects of Sal B on passaged chondrocytes. Chondrocytes were treated with various concentrations of Sal B in monolayer culture, their morphological properties and changes, and mitochondrial membrane potential were analysed using microscopic analyses, including cellular biochemical staining and confocal laser scanning microscopy. The proteins were quantified by BCA and Western blotting, and the transcription of genes was detected by qRT-PCR. The passaged chondrocytes treated with Sal B showed strengthened cellular synthesis and stabilized mitochondrial membrane potential with upregulated expression of the marker genes for chondrocyte phenotype, Col2-α1, Acan and Sox9, the key Wnt signalling molecule β-catenin and paracrine cytokine Cytl-1. The treatments using CYTL-1 protein significantly increased expression of Col2-α1 and Acan with no effect on Sox9, indicating the paracrine cytokine acts on chondrocytes independent of SOX9. Sal B has ultimately promoted cell growth and enhanced chondrocyte phenotype. The chondrocytes treated with pharmaceutical agent and cytokine in the formulated medium for generating large number of differentiated chondrocytes would facilitate the cell-based therapies for cartilage repair.
Chin J Integr Med. 2017 Jan 24. doi: 10.1007/s11655-016-2645-4. [Epub ahead of print]
Salvianolic acid B attenuates oxidized low-density lipoprotein-induced endothelial cell apoptosis through inhibition of oxidative stress, p53, and caspase-3 pathways.
To investigate the effect of salvianolic acid B (Sal B) on oxidized low-density lipoprotein (ox-LDL)-induced human umbilical vein endothelial cells (HUVECs) apoptosis and the possible mechanism.
HUVECs were divided into 6 groups, including control group, ox-LDL group, vitamin C group (positive control), and 5, 10 and 20 μg/mL Sal B groups. Cell viability of HUVECs was determined by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The anti-apoptotic effect of Sal B was tested by Hoechst 33258 staining and Annexin V/propidium iodide flflow cytometry analysis. Apoptosis-related genes (p53, Bcl-2 and Bax) expression and caspase-3 activity were also determined. Oxidative stress markers malondialdehyde (MDA) and superoxide dismutase (SOD) were determined by the corresponding kits.
In HUVECs, ox-LDL signifificantly reduced cell viability and induced apoptosis (P<0.05 or P<0.01), however, Sal B diminished the effects of ox-LDL in a dose-dependent manner (P<0.05). Moreover, 10 and 20 μg/mL Sal B reduced the expression levels of p53, increased the Bcl-2/Bax ratio and inhibited the caspase-3 activity in ox-LDL-treated HUVECs (P<0.05). In addition, 5, 10 and 20 μg/mL Sal B signifificantly enhanced the activity of SOD, while decreased the level of MDA in the HUVECs which treated with ox-LDL (P<0.05).
Sal B exhibited anti-apoptotic effects in ox-LDL-induced endothelial cell injury by suppressing oxidative stress, p53, and caspase-3.
Mol Med Rep. 2017 Feb;15(2):724-730. doi: 10.3892/mmr.2016.6049. Epub 2016 Dec 14.
Salvianolic acid B reverses multidrug resistance in HCT‑8/VCR human colorectal cancer cells by increasing ROS levels.
Salvianolic acid B (SalB) a water‑soluble phenolic compound, extracted from Salvia miltiorrhiza, has previously been demonstrated to reverse tumor multidrug resistance (MDR), including in colorectal cancer. Reactive oxygen species (ROS) are oxygen radicals generated during aerobic metabolism (superoxide and hydroxyl radicals) and superoxide easily generating free radicals (H2O2). The concept that increased ROS levels can lead to augmented tumor cell‑sensitivity to chemotherapy drugs has become notable. The aim of the present study was to elucidate the role of ROS in mediating the effect of SalB on drug resistance and the correlation with drug resistance‑associated protein, P‑glycoprotein (P‑gp), and apoptosis‑associated proteins, B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X (Bax). In the current study, through utilizing the multidrug resistant colorectal cancer cell line, HCT‑8/VCR, it was demonstrate that SalB reversed MDR in HCT‑8/VCR. In addition, SalB significantly increased ROS levels, which may have accelerated the apoptosis of HCT‑8/VCR cells by downregulating Bcl‑2 and increasing Bax protein expression. Furthermore the increased intracellular ROS levels may have inhibited P‑gp expression at the gene and protein levels. In conclusion, the data of the current study demonstrate that SalB reversed MDR in HCT‑8/VCR cells, and the effect is associated with increased ROS levels, which may downregulate P‑gp expression and promote tumor cell apoptosis, which in turn increases the sensitivity of drug‑resistant cells to chemotherapy drugs.
PLoS One. 2016 Nov 28;11(11):e0166560. doi: 10.1371/journal.pone.0166560. eCollection 2016.
Salvianolic Acid B Alleviates Heart Failure by Inactivating ERK1/2/GATA4 Signaling Pathway after Pressure Overload in Mice.
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.
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.
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.
Our data provide a mechanism of inactivating the ERK1/2/GATA4 signaling pathway for SalB inhibition of the TAC-induced HF.
J Orthop Surg Res. 2016 Nov 16;11(1):141.
Salvianolic acid B reduced the formation of epidural fibrosis in an experimental rat model.
Salvianolic acid B (Sal B) was newly reported to be able to attenuate fibrosis in the animal model. The aim of the present study was to investigate the effect of the intragastric application of Sal B on the prevention of epidural fibrosis (EF).
Forty healthy adult male Wistar rats were divided into four treatment groups (n = 10 per group): (1) 10 mg/kg Sal B, (2) 30 mg/kg Sal B, (3) 50 mg/kg Sal B and (4) Saline (vehicle treatment, control group). All animals underwent a laminectomy at the lumbar 1-2 (L 1-2) level. After intragastric treatment, all rats were sacrificed at post-operative week 8. The extent of the epidural scar, the regeneration of the vasculature and the expression levels of vascular endothelial growth factor (VEGF) were analysed.
The animals' recovery was uneventful during the experimental period. The extent of the epidural scar, the regeneration of the vasculature and the expression levels of VEGF suggested better outcomes in the Sal B-treated groups. Sal B exerted the ability to prevent the formation of an epidural scar and vascularization at the laminectomy sites. The effects of Sal B were dose-dependent, with the 50 mg/kg Sal B group showing the best outcomes compared with the other groups.
Post-operative intragastric application of Sal B can prevent the formation of epidural scarring. Sal B exerted these effects in a dose-dependent manner, and 50 mg/kg dose was shown to be the best effect in the present study. The results of this study reveal that Sal B could be a potential therapy for EF and valuable for further research.
Cell Physiol Biochem. 2016;40(5):933-943. Epub 2016 Dec 7.
Salvianolic Acid B Ameliorates Hyperglycemia and Dyslipidemia in db/db Mice through the AMPK Pathway.
Salvianolic acid B (Sal B), a major polyphenolic compound of Salvia miltiorrhiza Bunge, has been shown to possess potential antidiabetic activities. However, the action mechanism of SalB in type 2 diabetes has not been investigated extensively. The present study was designed to investigate the effects of Sal B on diabetes-related metabolic changes in a spontaneous model of type 2 diabetes, as well as its potential molecular mechanism.
Male C57BL/KsJ-db/db mice were orally treated with Sal B (50 and 100 mg/kg) or metformin (positive drug, 300 mg/kg) for 6 weeks.
Both doses of Sal B significantly decreased fasting blood glucose, serum insulin, triglyceride and free fatty acid levels, reduced hepatic gluconeogenic gene expression and improved insulin intolerance in db/db mice. High dose Sal B also significantly improved glucose intolerance, increased hepatic glycolytic gene expression and muscle glycogen content, and ameliorated histopathological alterations of pancreas, similar to metformin. Sal B treatment resulted in increased phosphorylated AMP-activated protein kinase (p-AMPK) protein expression in skeletal muscle and liver, increased glucose transporter 4 (GLUT4) and glycogen synthase protein expressions in skeletal muscle, and increased peroxisome proliferator-activated receptor alpha (PPARα) and phosphorylated acetyl CoA carboxylase (p-ACC) protein expressions in liver.
Our data suggest that Sal B displays beneficial effects in the prevention and treatment of type 2 diabetes at least in part via modulation of the AMPK pathway.
Trop J Pharm Res, January 2014;13 (1):53
Description:Purpose: To evaluate the effect of salvianolic acid B (Sal B) treatment on the motor function of spinal cord injury (SCI) rat.
Methods: SCI rats were modelled by contusion, and then received 10 mg/kg Sal B, or methylprednisolone, or phosphate-buffered saline (PBS) intraperitoneally daily for 4 weeks, two hours after the trauma occurred. During the treatment, footprint analysis (FA), inclined plane test (IPT), Basso-Beattie-Bresnahan (BBB) rating and Schnell Swim Test (SST) were used for estimating the recovery of motor function. At the same time, tissue edema was measured by wet-dry weighting, and the secretion of cytokines were indirectly quantitated by real time polymerase chain reaction (qPCR).
Injured rats that received 10 mg/kg Sal B demonstrated much stronger functional capacity compared to controls. Sal B group rats scored higher by FA, IPT and BBB rating. Further statistical analysis of comprehensive SST data from Student-t test indicates that Sal B can significantly ameliorate motor dysfunction after a 4-week treatment (p< 0.05) as well. Furthermore, Sal B decreased water content of the edema by 16.5 % during the first week, and sharply downregulated the transcription of interleukin 6 (IL-6) and tumor necrosis factor (TNF-α) 28- and 16-fold, respectively.
Conclusion: The beneficial effect of motor function recovery was observed in SCI rats following intraperitoneal administration of Sal B.
Keywords: Salvianolic acid B, Spinal cord injury, Motor dysfunction, Cytokines
Test of tissue edema
All forms of injury can cause spinal cord edema, further decreasing blood flow and oxygenation.
Edema is one of the secondary events which might aggravate a primary injury and there are reasons to believe that compounds, like SalB, might be useful to ameliorate the adverse effect. As one of the most important traditional herbal medicines, it is widely used in clinic in China, Japan, and other countries for the treatment of coronary artery disease and other cardiovascular diseases. The wet and dry weight method was used to evaluate the extent of tissue edema.
Sal B treatment can significantly downregulate the transcription of IL- 6 and TNF-α, about 28-fold and 16-fold respectively. The sharp fluctuations of IL-6 and TNF-α may play important role in the recovery of motor function to a certain extent.
The antioxidant Sal B has been shown to improve functional recovery in brain injured rats and provide neuroprotective effects in some experimental models of cerebral ischemia [6,7]. Recently, Deng et al. reported that Sal B improved motor function are partially due to inhibition of increased TNF-α in the damaged spinal cord and exhibits neuroprotective effects.