Methionine redox regulation of actin-interacting proteins primarily governs antioxidative signaling and response to the salvianolic acid B treatment in EA.hy926 cells.

Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.

A novel natural Syk inhibitor suppresses IgE-mediated mast cell activation and passive cutaneous anaphylaxis.

Spleen tyrosine kinase (Syk) plays a crucial role as a target for allergy treatment due to its involvement in immunoreceptor signaling. The purpose of this study was to identify natural inhibitors of Syk and assess their effects on the IgE-mediated allergic response in mast cells and ICR mice. A list of eight compounds was selected based on pharmacophore and molecular docking, showing potential inhibitory effects through virtual screening. Among these compounds, sophoraflavanone G (SFG) was found to inhibit Syk activity in an enzymatic assay, with an IC50 value of 2.2 µM. To investigate the conformational dynamics of the SYK-SFG system, we performed molecular dynamics simulations. The stability of the binding between SFG and Syk was evaluated using root mean square deviation (RMSD) and root mean square fluctuation (RMSF). In RBL-2H3 cells, SFG demonstrated a dose-dependent suppression of IgE/BSA-induced mast cell degranulation, with no significant cytotoxicity observed at concentrations below 10.0 µM within 24 h. Furthermore, SFG reduced the production of TNF-α and IL-4 in RBL-2H3 cells. Mechanistic investigations revealed that SFG inhibited downstream signaling proteins, including phospholipase Cγ1 (PLCγ1), as well as mitogen-activated protein kinases (AKT, Erk1/2, p38, and JNK), in mast cells in a dose-dependent manner. Passive cutaneous anaphylaxis (PCA) experiments demonstrated that SFG could reduce ear swelling, mast cell degranulation, and the expression of COX-2 and IL-4. Overall, our findings identify naturally occurring SFG as a direct inhibitor of Syk that effectively suppresses mast cell degranulation both in vitro and in vivo.

Pharmacodynamic study of chitosan in combination with salvianolic acid B in the treatment of CC14 -induced liver fibrosis in mice.

Liver fibrosis is a chronic liver lesion caused by excessive deposition of the extracellular matrix after liver damage, resulting in fibrous scarring of liver tissue. The progression of liver fibrosis is partially influenced by the gut microbiota. Chitosan can play a therapeutic role in liver fibrosis by regulating the gut microbiota based on the 'gut-liver axis' theory. Salvianolic acid B can inhibit the development of liver fibrosis by inhibiting the activation of hepatic stellate cells and reducing the production of extracellular matrix. In this study, the therapeutic effect of chitosan in combination with salvianolic acid B on liver fibrosis was investigated in a mouse liver fibrosis model. The results showed that the combination of chitosan and salvianolic acid B was better than the drug alone, improving AST/ALT levels and reducing the expression of α-SAM, COL I, IL-6 and other related genes. It improved the structure of gut microbiota and increased the abundance of beneficial bacteria such as Lactobacillus. The above results could provide new ideas for the clinical treatment of liver fibrosis.

Salvianolic acid B protects against pulmonary fibrosis by attenuating stimulating protein 1-mediated macrophage and alveolar type 2 cell senescence.

Idiopathic pulmonary fibrosis (IPF), as the most common idiopathic interstitial pneumonia, is caused by a complex interaction of pathological mechanisms. Interestingly, IPF frequently occurs in the middle-aged and elderly populations but rarely affects young people. Salvianolic acid B (SAB) exerts antioxidant, antiinflammatory, and antifibrotic bioactivities and is considered a promising drug for pulmonary disease treatment. However, the pharmacological effects and mechanisms of SAB on cellular senescence of lung cells and IPF development remain unclear. We used bleomycin (BLM)-induced pulmonary fibrosis mice and different lung cells to investigate the antisenescence impact of SAB and explain its underlying mechanism by network pharmacology and the Human Protein Atlas database. Here, we found that SAB significantly prevented pulmonary fibrosis and cellular senescence in mice, and reversed the senescence trend and typical senescence-associated secretory phenotype (SASP) factors released from lung macrophages and alveolar type II (AT2) epithelial cells, which further reduced lung fibroblasts activation. Additionally, SAB alleviated the epithelial-mesenchymal transition process of AT2 cells induced by transforming growth factor beta. By predicting potential targets of SAB that were then confirmed by chromatin immunoprecipitation-qPCR technology, we determined that SAB directly hampered the binding of transcription factor stimulating protein 1 to the promoters of SASPs (P21 and P16), thus halting lung cell senescence. We demonstrated that SAB reduced BLM-induced AT2 and macrophage senescence, and the subsequent release of SASP factors that activated lung fibroblasts, thereby dual-relieving IPF. This study provides a new scientific foundation and perspective for pulmonary fibrosis therapy.

Salvianolic acid B alleviates autoimmunity in Treg-deficient mice via inhibiting IL2-STAT5 signaling.

Regulatory T cell (Treg) deficiency leads to immune dysregulation, polyendocrinopathy, enteropathy, and X-linked (IPEX) syndrome, which is a CD4+ T cell-driven autoimmune disease in both humans and mice. Despite understanding the molecular and cellular characteristics of IPEX syndrome, new treatment options have remained elusive. Here, we hypothesized that salvianolic acid B (Sal B), one of the main active ingredients of Salvia miltiorrhiza, can protect against immune disorders induced by Treg deficiency. To examine whether Sal B can inhibit Treg deficiency-induced autoimmunity, Treg-deficient scurfy (SF) mice with a mutation in forkhead box protein 3 were treated with different doses of Sal B. Immune cells, inflammatory cell infiltration, and cytokines were evaluated by flow cytometry, hematoxylin and eosin staining and enzyme-linked immunosorbent assay Kits, respectively. Moreover, RNA sequencing, western blot, and real-time PCR were adopted to investigate the molecular mechanisms of action of Sal B. Sal B prolonged lifespan and reduced inflammation in the liver and lung of SF mice. Moreover, Sal B decreased plasma levels of several inflammatory cytokines, such as IL-2, IFN-γ, IL-4, TNF-α, and IL-6, in SF mice. By analyzing the transcriptomics of livers, we determined the signaling pathways, especially the IL-2-signal transducer and activator of transcription 5 (STAT5) signaling pathway, which were associated with Treg deficiency-induced autoimmunity. Remarkably, Sal B reversed the expression of gene signatures related to the IL-2-STAT5 signaling pathway in vitro and in vivo. Sal B prolongs survival and inhibits lethal inflammation in SF mice through the IL-2-STAT5 axis. Our findings may inspire novel drug discovery efforts aimed at treating IPEX syndrome.

Genome-Wide Identification and Functional Analysis of Salvia miltiorrhiza MicroRNAs Reveal the Negative Regulatory Role of Smi-miR159a in Phenolic Acid Biosynthesis.

MicroRNAs (miRNAs) are a group of endogenous small non-coding RNAs in plants. They play critical functions in various biological processes during plant growth and development. Salvia miltiorrhiza is a well-known traditional Chinese medicinal plant with significant medicinal, economic, and academic values. In order to elucidate the role of miRNAs in S. miltiorrhiza, six small RNA libraries from mature roots, young roots, stems, mature leaves, young leaves and flowers of S. miltiorrhiza and one degradome library from mixed tissues were constructed. A total of 184 miRNA precursors, generating 137 known and 49 novel miRNAs, were genome-widely identified. The identified miRNAs were predicted to play diversified regulatory roles in plants through regulating 891 genes. qRT-PCR and 5' RLM-RACE assays validated the negative regulatory role of smi-miR159a in SmMYB62, SmMYB78, and SmMYB80. To elucidate the function of smi-miR159a in bioactive compound biosynthesis, smi-miR159a transgenic hairy roots were generated and analyzed. The results showed that overexpression of smi-miR159a caused a significant decrease in rosmarinic acid and salvianolic acid B contents. qRT-PCR analysis showed that the targets of smi-miR159a, including SmMYB62, SmMYB78, and SmMYB80, were significantly down-regulated, accompanied by the down-regulation of SmPAL1, SmC4H1, Sm4CL1, SmTAT1, SmTAT3, SmHPPR1, SmRAS, and SmCYP98A14 genes involved in phenolic acid biosynthesis. It suggests that smi-miR159a is a significant negative regulator of phenolic acid biosynthesis in S. miltiorrhiza.

Salvianolic Acid B Significantly Suppresses the Migration of Melanoma Cells via Direct Interaction with ß-Actin.

Melanoma is the most aggressive and difficult to treat of all skin cancers. Despite advances in the treatment of melanoma, the prognosis for melanoma patients remains poor, and the recurrence rate remains high. There is substantial evidence that Chinese herbals effectively prevent and treat melanoma. The bioactive ingredient Salvianolic acid B (SAB) found in Salvia miltiorrhiza, a well-known Chinese herbal with various biological functions, exhibits inhibitory activity against various cancers. A375 and mouse B16 cell lines were used to evaluate the main targets and mechanisms of SAB in inhibiting melanoma migration. Online bioinformatics analysis, Western blotting, immunofluorescence, molecular fishing, dot blot, and molecular docking assays were carried out to clarify the potential molecular mechanism. We found that SAB prevents the migration and invasion of melanoma cells by inhibiting the epithelial-mesenchymal transition (EMT) process of melanoma cells. As well as interacting directly with the N-terminal domain of ß-actin, SAB enhanced its compactness and stability, thereby inhibiting the migration of cells. Taken together, SAB could significantly suppress the migration of melanoma cells via direct binding with ß-actin, suggesting that SAB could be a helpful supplement that may enhance chemotherapeutic outcomes and benefit melanoma patients.

Salvianolic Acid B Alleviates Liver Injury by Regulating Lactate-Mediated Histone Lactylation in Macrophages.

Salvianolic acid B (Sal B) is the primary water-soluble bioactive constituent derived from the roots of Salvia miltiorrhiza Bunge. This research was designed to reveal the potential mechanism of Sal B anti-liver injury from the perspective of macrophages. In our lipopolysaccharide-induced M1 macrophage model, Sal B showed a clear dose-dependent gradient of inhibition of the macrophage trend of the M1 type. Moreover, Sal B downregulated the expression of lactate dehydrogenase A (LDHA), while the overexpression of LDHA impaired Sal B's effect of inhibiting the trend of macrophage M1 polarization. Additionally, this study revealed that Sal B exhibited inhibitory effects on the lactylation process of histone H3 lysine 18 (H3K18la). In a ChIP-qPCR analysis, Sal B was observed to drive a reduction in H3K18la levels in the promoter region of the LDHA, NLRP3, and IL-1ß genes. Furthermore, our in vivo experiments showed that Sal B has a good effect on alleviating CCl4-induced liver injury. An examination of liver tissues and the Kupffer cells isolated from those tissues proved that Sal B affects the M1 polarization of macrophages and the level of histone lactylation. Together, our data reveal that Sal B has a potential mechanism of inhibiting the histone lactylation of macrophages by downregulating the level of LDHA in the treatment of liver injury.

Injectable Hydrogels Based on Hyaluronic Acid and Gelatin Combined with Salvianolic Acid B and Vascular Endothelial Growth Factor for Treatment of Traumatic Brain Injury in Mice.

Traumatic brain injury (TBI) leads to structural damage in the brain, and is one of the major causes of disability and death in the world. Herein, we developed a composite injectable hydrogel (HA/Gel) composed of hyaluronic acid (HA) and gelatin (Gel), loaded with vascular endothelial growth factor (VEGF) and salvianolic acid B (SAB) for treatment of TBI. The HA/Gel hydrogels were formed by the coupling of phenol-rich tyramine-modified HA (HA-TA) and tyramine-modified Gel (Gel-TA) catalyzed by horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H2O2). SEM results showed that HA/Gel hydrogel had a porous structure. Rheological test results showed that the hydrogel possessed appropriate rheological properties, and UV spectrophotometry results showed that the hydrogel exhibited excellent SAB release performance. The results of LIVE/DEAD staining, CCK-8 and Phalloidin/DAPI fluorescence staining showed that the HA/Gel hydrogel possessed good cell biocompatibility. Moreover, the hydrogels loaded with SAB and VEGF (HA/Gel/SAB/VEGF) could effectively promote the proliferation of bone marrow mesenchymal stem cells (BMSCs). In addition, the results of H&E staining, CD31 and α-SMA immunofluorescence staining showed that the HA/Gel/SAB/VEGF hydrogel possessed good in vivo biocompatibility and pro-angiogenic ability. Furthermore, immunohistochemical results showed that the injection of HA/Gel/SAB/VEGF hydrogel to the injury site could effectively reduce the volume of defective tissues in traumatic brain injured mice. Our results suggest that the injection of HA/Gel hydrogel loaded with SAB and VEGF might provide a new approach for therapeutic brain tissue repair after traumatic brain injury.

Neuroprotective Effects of Geopung-Chunghyuldan Based on Its Salvianolic Acid B Content Using an In Vivo Stroke Model.

BACKGROUND: Geopung-Chunghyuldan (GCD) has neuroprotective properties. Salviae miltiorrhizae Radix plays an essential role in GCD's effect. The Salviae miltiorrhizae Radix marker compound is salvianolic acid B; however, its content is not uniform among samples. This study aimed to evaluate the neuroprotective effects of GCD based on salvianolic acid B content. METHODS: The neuroprotective effects of GCD based on the salvianolic acid B content were evaluated by measuring infarct volume 24 h after permanent middle cerebral artery occlusion in an in vivo stroke model. For the experimental group, each GCD was administered immediately before surgery. The control groups were administered distilled water and aspirin (30 mg/kg) in the same way. The salvianolic acid B content in five types of Salviae Miltiorrhizae Radix (two Chinese and three Korean regions) based on different cultivation regions was analyzed by high-performance liquid chromatography. RESULTS: Three samples met the Korean and Chinese Pharmacopeia standards for salvianolic acid B. However, two samples did not. GCDs with high salvianolic acid B showed marked neuroprotective effects compared to the control groups, whereas GCDs with low salvianolic acid B did not. CONCLUSIONS: The salvianolic acid B content of Salviae miltiorrhizae Radix affects the neuroprotection effect of GCD. Stable, raw Salviae miltiorrhizae Radix is essential for GCD homogenization.

Protective effects of salvianolic acid B on intestinal ischemia/reperfusion injury in rats by regulating the AhR/IL-22/STAT6 axis.

PURPOSE: Intestinal ischemia/reperfusion (I/R) injury (IIRI) is associated with high morbidity and mortality. Salvianolic acid B (Sal-B) could exert neuroprotective effects on reperfusion injury after cerebral vascular occlusion, but its effect on IIRI remains unclear. This study set out to investigate the protective effects of Sal-B on IIRI in rats. METHODS: The rat IIRI model was established by occluding the superior mesenteric artery and reperfusion, and they were pretreated with Sal-B and aryl hydrocarbon receptor (AhR) antagonist CH-223191 before surgery. Pathological changes in rat ileum, IIRI degree, and intestinal cell apoptosis were evaluated through hematoxylin-eosin staining, Chiu's score scale, and TUNEL staining, together with the determination of caspase-3, AhR protein level in the nucleus, and STAT6 phosphorylation by Western blotting. The levels of inflammatory cytokines (IL-1ß/IL-6/TNF-α) and IL-22 were determined by ELISA and RT-qPCR. The contents of superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) in intestinal tissues were determined by spectrophotometry. RESULTS: Sal-B alleviated IIRI in rats, evidenced by slight villi shedding and villi edema, reduced Chiu's score, and diminished the number of TUNEL-positive cells and caspase-3 expression. SAL-B alleviated inflammation and oxidative stress (OS) responses induced by IIRI. Sal-B promoted IL-22 secretion by activating AhR in intestinal tissue after IIRI. Inhibition of AhR activation partially reversed the protective effect of Sal-B on IIRI. Sal-B promoted STAT6 phosphorylation by activating the AhR/IL-22 axis. CONCLUSION: Sal-B plays a protective role against IIRI in rats by activating the AhR/IL-22/STAT6 axis, which may be achieved by reducing the intestinal inflammatory response and OS responses.

Protein acetylation and related potential therapeutic strategies in kidney disease.

Kidney disease can be caused by various internal and external factors that have led to a continual increase in global deaths. Current treatment methods can alleviate but do not markedly prevent disease development. Further research on kidney disease has revealed the crucial function of epigenetics, especially acetylation, in the pathology and physiology of the kidney. Histone acetyltransferases (HATs), histone deacetylases (HDACs), and acetyllysine readers jointly regulate acetylation, thus affecting kidney physiological homoeostasis. Recent studies have shown that acetylation improves mechanisms and pathways involved in various types of nephropathy. The discovery and application of novel inhibitors and activators have further confirmed the important role of acetylation. In this review, we provide insights into the physiological process of acetylation and summarise its specific mechanisms and potential therapeutic effects on renal pathology.

Salvianolic Acid B Inhibits Oxidative Stress in Glomerular Mesangial Cells Alleviating Diabetic Nephropathy by Regulating SIRT3/FOXO1 Signaling.

INTRODUCTION: Oxidative stress is pivotal in advancing diabetic nephropathy (DN). Salvianolic acid B (SAB), derived from Radix Salviae miltiorrhizae, exhibits renoprotective effects. However, the mechanisms underlying its action in DN are not fully elucidated. This study explores SAB's protective effect on DN, focusing on its antioxidative properties in glomerular mesangial cells. METHODS: The renoprotective effects of various SAB dosages on DN rats were assessed by evaluating kidney tissue pathological alterations through hematoxylin and eosin, periodic acid-Schiff, Masson, TUNEL staining, and kidney function through biochemical detection. Cell counting kit-8 and lactate dehydrogenase cytotoxicity assays were utilized to evaluate the viability of high glucose (HG)-induced HBZY-1 cells treated with various SAB dosages. Oxidative stress and inflammation levels were measured using enzyme-linked immunosorbent assay kits. The Sirtuin 3 (SIRT3)/Forkhead box transcription factor O1 (FOXO1) pathway was examined through Western blot and immunohistochemistry. RESULTS: SAB mitigated kidney histopathological alterations and function and cell apoptosis in DN rats at various dosages. It enhanced the activity of glutathione peroxidase and superoxide dismutase while decreasing reactive oxygen species and malondialdehyde levels both in vivo and in vitro. SAB also suppressed the levels of pro-inflammatory cytokines (IL-1ß, IL-6, MCP-1, and TNF-α) and the expression of collagen IV and fibronectin in HG-induced HBZY-1 cells. Furthermore, SAB activated the SIRT3/FOXO1 signaling pathway. CONCLUSION: Our findings suggest that SAB may alleviate oxidative stress in DN both in vivo and in vitro, potentially through the activation of the SIRT3/FOXO1-mediated signaling pathway. This study provides initial insights into the possible antioxidative and renoprotective effects of SAB, indicating its potential utility as a therapeutic agent for DN.

Salvianolic acid B suppresses hepatic fibrosis by inhibiting ceramide glucosyltransferase in hepatic stellate cells.

UDP-glucose ceramide glucosyltransferase (UGCG) is the first key enzyme in glycosphingolipid (GSL) metabolism that produces glucosylceramide (GlcCer). Increased UGCG synthesis is associated with cell proliferation, invasion and multidrug resistance in human cancers. In this study we investigated the role of UGCG in the pathogenesis of hepatic fibrosis. We first found that UGCG was over-expressed in fibrotic livers and activated hepatic stellate cells (HSCs). In human HSC-LX2 cells, inhibition of UGCG with PDMP or knockdown of UGCG suppressed the expression of the biomarkers of HSC activation (α-SMA and collagen I). Furthermore, pretreatment with PDMP (40 µM) impaired lysosomal homeostasis and blocked the process of autophagy, leading to activation of retinoic acid signaling pathway and accumulation of lipid droplets. After exploring the structure and key catalytic residues of UGCG in the activation of HSCs, we conducted virtual screening, molecular interaction and molecular docking experiments, and demonstrated salvianolic acid B (SAB) from the traditional Chinese medicine Salvia miltiorrhiza as an UGCG inhibitor with an IC50 value of 159 µM. In CCl4-induced mouse liver fibrosis, intraperitoneal administration of SAB (30 mg · kg-1 · d-1, for 4 weeks) significantly alleviated hepatic fibrogenesis by inhibiting the activation of HSCs and collagen deposition. In addition, SAB displayed better anti-inflammatory effects in CCl4-induced liver fibrosis. These results suggest that UGCG may represent a therapeutic target for liver fibrosis; SAB could act as an inhibitor of UGCG, which is expected to be a candidate drug for the treatment of liver fibrosis.

Salvianolic acid B ameliorates retinal deficits in an early-stage Alzheimer's disease mouse model through downregulating BACE1 and Aß generation.

Alzheimer's disease (AD) is a neurodegenerative disease with subtle onset, early diagnosis remains challenging. Accumulating evidence suggests that the emergence of retinal damage in AD precedes cognitive impairment, and may serve as a critical indicator for early diagnosis and disease progression. Salvianolic acid B (Sal B), a bioactive compound isolated from the traditional Chinese medicinal herb Salvia miltiorrhiza, has been shown promise in treating neurodegenerative diseases, such as AD and Parkinson's disease. In this study we investigated the therapeutic effects of Sal B on retinopathy in early-stage AD. One-month-old transgenic mice carrying five familial AD mutations (5×FAD) were treated with Sal B (20 mg·kg-1·d-1, i.g.) for 3 months. At the end of treatment, retinal function and structure were assessed, cognitive function was evaluated in Morris water maze test. We showed that 4-month-old 5×FAD mice displayed distinct structural and functional deficits in the retinas, which were significantly ameliorated by Sal B treatment. In contrast, untreated, 4-month-old 5×FAD mice did not exhibit cognitive impairment compared to wild-type mice. In SH-SY5Y-APP751 cells, we demonstrated that Sal B (10 µM) significantly decreased BACE1 expression and sorting into the Golgi apparatus, thereby reducing Aß generation by inhibiting the ß-cleavage of APP. Moreover, we found that Sal B effectively attenuated microglial activation and the associated inflammatory cytokine release induced by Aß plaque deposition in the retinas of 5×FAD mice. Taken together, our results demonstrate that functional impairments in the retina occur before cognitive decline, suggesting that the retina is a valuable reference for early diagnosis of AD. Sal B ameliorates retinal deficits by regulating APP processing and Aß generation in early AD, which is a potential therapeutic intervention for early AD treatment.

Salvianolic acid B attenuates diabetic nephropathy through alleviating ADORA2B, NALP3 in flammasome, and NFκB activity.

Diabetic nephropathy is one of the microvascular complications of diabetes. This study is aimed at investigating the role and mechanisms of salvianolic acid B (Sal B) in diabetic nephropathy. High glucose (HG)-induced human renal tubular epithelial HK-2 cells were treated with Sal B, BAY-60-6583 (agonist of adenosine 2B receptor), or PSB-603 (antagonist of adenosine 2B receptor) for 24 h. Adenosine A2b receptor (ADORA2B), NACHT, leucine-rich repeat (LRR), and pyrin (PYD) domains-containing protein 3 (NALP3), and nuclear factor Kappa B (NFκB) expressions, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) levels were examined. Following 6 weeks of Sal B treatment, db/db mice blood and kidney tissue were harvested for biochemical detection with hematoxylin-eosin (H&E), Masson's, periodic acid schiff (PAS), and Sirius red staining and detection of ADORA2B, NALP3, NFκB, interleukin 1ß (IL-1ß), and toll-like receptor 4 (TLR4) activity. NFκB, NALP3, and ADORA2B were found to be downregulated in Sal B treated HK-2 cells exposed to high glucose (HG), accompanied by elevated levels of MMPs and reduced intracellular ROS production. Sal B-treated diabetic mice had the improvement in body weight, water intake, hyperglycemia, hyperlipidemia, and liver and kidney function. Altogether, Sal B attenuates HG-induced kidney tubule cell injury and diabetic nephropathy in diabetic mice, providing clues to other novel mechanisms by which Sal B is beneficial in diabetic nephropathy.

Salvianolic acid B, a new type I IRE1 kinase inhibitor, abrogates AngII-induced angiogenesis by interacting with IRE1 in its active conformation.

Angiotensin II (AngII)-mediated pathological angiogenesis is one of the important factors promoting the progression of atherosclerosis, tumour metastasis, and diabetic retinopathy. Here, we first demonstrate that salvianolic acid B (Sal B) attenuated AngII-induced angiogenesis by downregulating the IRE1/ASK1/JNK/p38MAPK signalling pathway and protected vascular endothelial cells from hypoxia-induced damage. These pharmacological consequences could be ascribed to the unique interactions between Sal B and the ATP-binding cavity of IREIα, leading to bi-directional roles of IRE1 kinase and endonuclease activity; this may possibly be one of the essential mechanisms of the bi-directional regulation of angiogenesis in different conditions. Moreover, our results indicated that IRE1 was a novel anti-angiogenesis target and type I IRE1 kinase inhibitor (e.g., Sal B, APY29) and might be a potentially eligible low-toxicity drug for treating AngII-mediated pathological angiogenesis.

Salvianolic acid B as a potent nano-agent for enhanced ALA-PDT of oral cancer and leukoplakia cells.

BACKGROUND: Photodynamic therapy (PDT) relies on the light activation of a photosensitizers to generate reactive oxygen species such as singlet oxygen, but its effect on cancer therapy is limited dramatically by hypoxia in the tumor microenvironment. OBJECTIVES: To determine the potential of a nano-photosensitizer loaded salvianolic acid B (SalB) and 5-aminolevulinic acid (ALA) for enhancing the efficacy of PDT in oral squamous cell carcinoma Cal27 cells and leukoplakia Leuk1 cells. RESULTS: Singlet oxygen sensor green (SOSG) assay showed that nano-SalB-ALA generated higher levels of singlet oxygen, compared to nano-SalB and nano-ALA. Cellular uptake assay showed that nano-SalB-ALA effectively absorbed by Leuk1 cells. Importantly, cell counting kit-8 and flow cytometry revealed that PDT with nano-SalB-ALA effectively inhibited the viability and induced the apoptosis of Cal27 and Leuk1 cells, respectively. Moreover, the tumor xenograft study revealed that PDT with nano-SalB-ALA had a stronger inhibitory effect on tumor growth of nude mice, compared to control groups. CONCLUSIONS: The novel photosensitizer nano-SalB-ALA remarkably enhanced the efficacy of PDT by improving singlet oxygen production, inhibiting cell proliferation, promoting cell apoptosis, and suppressing tumor growth. These suggest PDT with nano-SalB-ALA could be a clinically significant and potent treatment for oral cancer and leukoplakia.

Salvianolic Acid B Attenuates Hypertrophic Scar Formation In Vivo and In Vitro.

BACKGROUND: Hypertrophic scars (HTSs) are a fibroproliferative disorder that occur following skin injuries. Salvianolic acid B (Sal-B) is an extractant from Salvia miltiorrhiza that has been reported to ameliorate fibrosis in multiple organs. However, the antifibrotic effect on HTSs remains unclear. This study aimed to determine the antifibrotic effect of Sal-B in vitro and in vivo. METHODS: In vitro, hypertrophic scar-derived fibroblasts (HSFs) were isolated from human HTSs and cultured. HSFs were treated with (0, 10, 50, 100 µmol/L) Sal-B. Cell proliferation and migration were evaluated by EdU, wound healing, and transwell assays. The protein and mRNA levels of TGFßI, Smad2, Smad3, α-SMA, COL1, and COL3 were detected by Western blots and real-time PCR. In vivo, tension stretching devices were fixed on incisions for HTS formation. The induced scars were treated with 100 µL of Sal-B/PBS per day according to the concentration of the group and followed up for 7 or 14 days. The scar condition, collagen deposition, and α-SMA expression were analyzed by gross visual examination, H&E, Masson, picrosirius red staining, and immunofluorescence. RESULTS: In vitro, Sal-B inhibited HSF proliferation, migration, and downregulated the expression of TGFßI, Smad2, Smad3, α-SMA, COL1, and COL3 in HSFs. In vivo, 50 and 100 µmol/L Sal-B significantly reduced scar size in gross and cross-sectional observations, with decreased α-SMA expression and collagen deposition in the tension-induced HTS model. CONCLUSIONS: Our study demonstrated that Sal-B inhibits HSFs proliferation, migration, fibrotic marker expression and attenuates HTS formation in a tension-induced HTS model in vivo. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Salvianolic-Acid-B-Loaded HA Self-Healing Hydrogel Promotes Diabetic Wound Healing through Promotion of Anti-Inflammation and Angiogenesis.

Inflammatory dysfunction and angiogenesis inhibition are two main factors leading to the delayed healing of diabetic wounds. Hydrogels with anti-inflammatory and angiogenesis-promoting effects have been considered as promising wound care materials. Herein, a salvianolic acid B (SAB)-loaded hyaluronic acid (HA) self-healing hydrogel (HA/SAB) with anti-inflammatory and pro-angiogenesis capacities for diabetic wound healing is reported. The HA hydrogel was prepared via the covalent cross-linking of aldehyde groups in oxidized HA (OHA) and hydrazide groups in adipic dihydrazide (ADH)-modified HA (HA-ADH) with the formation of reversible acylhydrazone bonds. The obtained HA hydrogel exhibited multiple favorable properties such as porous structures, excellent self-healing properties, a sustainable release capacity of SAB, as well as excellent cytocompatibility. In addition, the effects of the SAB-loaded HA self-healing hydrogel were investigated via a full-thickness skin defect model using diabetic rats. The HA/SAB hydrogel showed enhanced skin regeneration effects with accelerated wound closure, shorter remaining dermal space length, thicker granulation tissue formation, and more collagen deposition. Furthermore, reduced inflammatory response and enhanced vascularization were found with HA/SAB2.5 hydrogel-treated wounds, indicating that the hydrogel promotes diabetic wound healing through the promotion of anti-inflammation and angiogenesis. Our results suggest that the fabricated SAB-loaded HA self-healing hydrogel is promising as a wound dressing for the treatment of diabetic wounds.