Vaccarin suppresses diabetic nephropathy through inhibiting the EGFR/ERK1/2 signaling pathway.

Diabetic nephropathy (DN) is recognized as one of the primary causes of chronic kidney disease and end-stage renal disease. Vaccarin (VAC) confers favorable effects on cardiovascular and metabolic diseases, including type 2 diabetes mellitus (T2DM). Nonetheless, the potential role and mechanism of VAC in the etiology of DN have yet to be completely elucidated. In this study, a classical mouse model of T2DM is experimentally induced via a high-fat diet (HFD)/streptozocin (STZ) regimen. Renal histological changes are assessed via H&E staining. Masson staining and immunohistochemistry (IHC) are employed to assess renal fibrosis. RT-PCR is utilized to quantify the mRNA levels of renal fibrosis, oxidative stress and inflammation markers. The levels of malondialdehyde (MDA) and reactive oxygen species (ROS), as well as the content of glutathione peroxidase (GSH-Px), are measured. The protein expressions of collagen I, TGF-ß1, α-SMA, E-cadherin, Nrf2, catalase, SOD3, SOD2, SOD1, p-ERK, p-EGFR (Y845), p-EGFR (Y1173), p-NFκB P65, t-ERK, t-EGFR and t-NFκB P65 are detected by western blot analysis. Our results reveal that VAC has a beneficial effect on DN mice by improving renal function and mitigating histological damage. This is achieved through its inhibition of renal fibrosis, inflammatory cytokine overproduction, and ROS generation. Moreover, VAC treatment effectively suppresses the process of epithelial-mesenchymal transition (EMT), a crucial characteristic of renal fibrosis, in high glucose (HG)-induced HK-2 cells. Network pharmacology analysis and molecular docking identify epidermal growth factor receptor (EGFR) as a potential target for VAC. Amino acid site mutations reveal that Lys-879, Ile-918, and Ala-920 of EGFR may mediate the direct binding of VAC to EGFR. In support of these findings, VAC reduces the phosphorylation levels of both EGFR and its downstream mediator, extracellular signal-regulated kinase 1/2 (ERK1/2), in diabetic kidneys and HG-treated HK-2 cells. Notably, blocking either EGFR or ERK1/2 yields renal benefits similar to those observed with VAC treatment. Therefore, this study reveals that VAC attenuates renal damage via inactivation of the EGFR/ERK1/2 signaling axis in T2DM patients.

Vaccarin improves insulin sensitivity and glucose uptake in diet-induced obese mice via activation of GPR120-PI3K/AKT/GLUT4 pathway.

Insulin resistance is a risk factor for type 2 diabetes and is often associated with obesity. Vaccarin, a flavonoid found in vaccaria seeds, is commonly used in traditional Chinese medicine for activating blood circulation. Here, we showed that vaccarin ameliorates high-fat diet-induced obesity and insulin resistance in mice by reducing fat accumulation and improving insulin sensitivity in white adipose tissue. Further hyperinsulinemic-euglycemic clamp test revealed enhanced glucose uptake in vaccarin-treated WAT and skeletal muscle, consistent with activated insulin signaling pathway in these tissues. Mechanistically, vaccarin activates adipose tissue GPR120 and subsequently activating the PI3K/AKT/GLUT4 signaling pathway in 3T3-L1 cells. Together, these results reveal an undiscovered function of vaccarin in preventing obesity-related insulin resistance and advocates that vaccarin holds promise for further development as an innovative agent for the prevention of metabolic disorders.

Suppression of apoptosis in vascular endothelial cell, the promising way for natural medicines to treat atherosclerosis.

Atherosclerosis, a chronic multifactorial disease, is closely related to the development of cardiovascular diseases and is one of the predominant causes of death worldwide. Normal vascular endothelial cells play an important role in maintaining vascular homeostasis and inhibiting atherosclerosis by regulating vascular tension, preventing thrombosis and regulating inflammation. Currently, accumulating evidence has revealed that endothelial cell apoptosis is the first step of atherosclerosis. Excess apoptosis of endothelial cells induced by risk factors for atherosclerosis is a preliminary event in atherosclerosis development and might be a target for preventing and treating atherosclerosis. Interestingly, accumulating evidence shows that natural medicines have great potential to treat atherosclerosis by inhibiting endothelial cell apoptosis. Therefore, this paper reviewed current studies on the inhibitory effect of natural medicines on endothelial cell apoptosis and summarized the risk factors that may induce endothelial cell apoptosis, including oxidized low-density lipoprotein (ox-LDL), reactive oxygen species (ROS), angiotensin II (Ang II), tumor necrosis factor-α (TNF-α), homocysteine (Hcy) and lipopolysaccharide (LPS). We expect this review to highlight the importance of natural medicines, including extracts and monomers, in the treatment of atherosclerosis by inhibiting endothelial cell apoptosis and provide a foundation for the development of potential antiatherosclerotic drugs from natural medicines.

Vaccarin Regulates Diabetic Chronic Wound Healing through FOXP2/AGGF1 Pathways.

BACKGROUND: Diabetes mellitus is a growing global health issue nearly across the world. Diabetic patients who are prone to develop diabetes-related complications often exhibit progressive neuropathy (painless and sensory loss). It is usual for small wounds to progress to ulceration, which especially worsens with peripheral arterial disease and in the presence of anaerobic bacteria, culminating into gangrene. In our study, vaccarin (VAC), the main active monomer extracted from Chinese herb vaccariae semen, is proven to have a role in promoting diabetic chronic wound healing through a cytoprotective role under high glucose conditions. MATERIALS AND METHODS: We constructed a pressure ulcer on both VAC-treated and control mice based on a type 1 diabetes (T1DM) model. The wound healing index was evaluated by an experimental wound assessment tool (EWAT). We also determined the effect of VAC on the proliferation and cell migration of human microvascular endothelial cells (HMEC-1) by a cell counting kit (CCK-8), a scratch and transwell assay. RESULTS: The results demonstrated that VAC could promote the proliferation and migration of high glucose-stimulated HMEC-1 cells, which depend on the activation of FOXP2/AGGF1. Activation of the angiogenic factor with G patch and FHA domains 1 (AGGF1) caused enhanced phosphorylation of serine/threonine kinase (Akt) and extracellular regulated protein kinases (Erk1/2). By silencing the expression of forkhead box p2 (FOXP2) protein by siRNA, both mRNA and protein expression of AGGF1 were downregulated, leading to a decreased proliferation and migration of HMEC-1 cells. In addition, a diabetic chronic wound model in vivo unveiled that VAC had a positive effect on chronic wound healing, which involved the activation of the above-mentioned pathways. CONCLUSIONS: In summary, our study found that VAC promoted chronic wound healing in T1DM mice by activating the FOXP2/AGGF1 pathway, indicating that VAC may be a promising candidate for the treatment of the chronic wounds of diabetic patients.

[Study on quality standard of fried Vaccariae Semen standard decoction].

According to the preparation principle of standard decoction of Chinese herbal medicines, fourteen batches of fried Vaccariae Semen decoction were prepared in this study and the quality research was carried out to establish a quality evaluation method for the standard decoction of fried Vaccariae Semen. The contents of vaccarin were determined, and its transfer rate from decoction piece to standard decoction was calculated. The extract rate and pH value were measured, and HPLC fingerprint method was established for analysis. The results of the 14 batches of samples revealed that the transfer rates of vaccarin were between 58.98%-93.94%; the extract rates were between 8.67%-17.83%, and the pH values were between 5.55-6.44. Moreover, 9 common chromatographic peaks were identified in fingerprints analysis. The similarities of the 14 batches of samples were analyzed and compared, and the results showed that the similarities were all higher than 0.96. In this study, the preparation process for fried Vaccariae Semen standard decoction was standard, with high similarities in fingerprint. A convenient and reliable method of comprehensive quality evaluation was established in this study, with a high precision, stability and repeatability, which can provide a reference for the quality control of fried Vaccariae Semen standard decoction, dispensing granule and related Chinese classical formulas(decoction).

Vaccarin prevents titanium particle-induced osteolysis and inhibits RANKL-induced osteoclastogenesis by blocking NF-κB and MAPK signaling pathways.

Wearing titanium particle-induced osteoclastogenesis, accompanied by peri-implant osteolysis, is the main cause of long-term failure of hip prosthesis. Currently, medications used for the prevention and treatment of peri-implant osteolysis show serious side effects. Therefore, development for more effective new drugs with less side effects is extremely urgent. Vaccarin is a natural flavonoid extracted from Vaccaria segetalis, with various biological functions, including antioxidantory, anti-inflammatory, and promotion of angiogenesis. However, the putative role of vaccarin in the inhibition of titanium particle-induced osteolysis has not been reported. In this study, it was indicated that vaccarin could effectively inhibit RANKL-induced osteoclastogenesis, fusion of F-actin rings, bone resorption, and expression of osteoclast marker genes in a dose-dependent manner in vitro. Moreover, vaccarin could also inhibit RANKL-induced osteoclastogenesis via the inhibition of NF-κB and MAPK (p38, ERK, and JNK) signaling pathways, and inhibit the transcription of downstream transcription factors, such as c-Fos and NFATc1. Consistent with in vitro results, this in vivo study showed that vaccarin exhibited an inhibitory effect on titanium particle-induced osteolysis by antiosteoclastogenesis. In conclusion, vaccarin could be a promising agent for preventing and treating peri-implant osteolysis.

Liquid chromatography-tandem mass spectrometric assay for the determination of vaccarin in rat plasma: application to a pharmacokinetic study.

Vaccarin, a flavonoid glycoside, is considered one of the major active constituents of Vaccaria segetalis. A simple and specific liquid chromatography-tandem mass spectrometric method was developed and validated for quantifying vaccarin in rat plasma following intravenous dosing. Plasma samples were precipitated with methanol and separated on a Venusil-C18 analytical column (2.1 × 50 mm, 5 µm particles) with gradient elution consisting of methanol and 0.1% (v/v) formic acid as the mobile phase. The detection was performed on an Agilent Triple Quad LC/MS with electrospray ionization inlet in the positive multiple reaction monitoring mode. Good linearity was achieved over the concentration range of 12.5-25,000 ng/mL (r(2) > 0.99). Intra- and inter-day precisions were <9.1%, and accuracy ranged from -2.8 to 8.7%. The lower limit of quantification for vaccarin was 12.5 ng/mL, and the analyte was stable under various storage conditions. This validated method was successfully applied to the preliminary pharmacokinetic studies of vaccarin following intravenous administrations of 1.21, 2.41, and 4.82 mg/kg vaccarin in rats.

Vaccarin Ameliorates Doxorubicin-Induced Cardiotoxicity via Inhibition of p38 MAPK Mediated Mitochondrial Dysfunction.

Doxorubicin is a frequently used chemotherapeutic agent for treating various malignancies. However, it leads to severe cardiotoxic side effects, such as heart failure, and elevates the risk of sudden cardiac death among cancer patients. While oxidative stress has been identified as the primary cause of doxorubicin-induced cardiotoxicity, therapeutic antioxidant approaches have yielded unsatisfactory outcomes. The aim of this study is to explore the therapeutic potential of vaccarin, an active flavonoid glycoside extracted from traditional Chinese herbal agent Semen Vaccariae, in doxorubicin-induced cardiotoxicity. We observed that vaccarin significantly ameliorates doxorubicin-induced heart dysfunction in mouse model and suppresses oxidative stress mediated cell apoptosis via specifically inhibiting the activation of p38 MAPK pathway. In vitro, we observed that vaccarin alleviates doxorubicin-induced mitochondrial membrane depolarization and ROS generation in H9c2 cell, but the p38 MAPK agonist anisomycin reverses these effects. Our findings provide a promising natural antioxidant to protect against DOX-induced cardiotoxicity.

Andrias Davidianus Mucus-Based Bioadhesive with Enhanced Adhesion and Wound Healing Properties.

The skin secretion of Andrias davidianus (SSAD) is a novel biological adhesive raw material under development. This material exhibits robust adhesion while maintaining the flexibility of the wound. It also has the potential for large-scale production, making it promising for practical application explore. Hence, in-depth research on methods to fine-tune SSAD properties is of great importance to promote its practical applications. Herein, we aim to enhance the adhesive and healing properties of SSAD by incorporating functional components. To achieve this goal, we selected 3,4-dihydroxy-l-phenylalanine and vaccarin as the functional components and mixed them with SSAD, resulting in a new bioadhesive, namely, a formulation termed "enhanced SSAD" (ESSAD). We found that the ESSAD exhibited superior adhesive properties, and its adhesive strength was improved compared with the SSAD. Moreover, ESSAD demonstrated a remarkable ability to promote wound healing. This study presents an SSAD-based bioadhesive formulation with enhanced properties, affirming the feasibility of developing SSAD-based adhesive materials with excellent performance and providing new evidence for the application of SSAD. This study also aims to show that SSAD can be mixed with other substances, and addition of effective components to SSAD can be studied to further adjust or improve its performance.

Vaccarin alleviates cisplatin-induced acute kidney injury via decreasing NOX4-derived ROS.

Cisplatin is a chemotherapeutant widely used in treating solid tumors, with the common side effect of acute kidney injury (AKI). Developing effective useful agent for preventing or treating cisplatin-induced AKI is of great importance. In this study, we investigate the protective effect of vaccarin, a chemical entity of flavonoid glycoside, against cisplatin-induced AKI. Cisplatin-treated C57BL/6J mice and human kidney-2 (HK-2) cells were used as the model of cisplatin-induced AKI. The levels of blood urea nitrogen (BUN) and creatine (Cr) levels and periodic acid-Schiff staining (PAS) scores decreased when vaccarin was administrated. Vaccarin had no impact on renal platinum accumulation, which was detected by the ICP-MS 6 h after cisplatin injection. Moreover, vaccarin can significantly alleviate the product of reactive oxygen species and the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) in cisplatin-induced AKI, both in vivo and in vitro. In addition, vaccarin decreased the receptor-interacting protein kinase 1 (RIPK1) related programmed necrosis (necroptosis), cell apoptosis (shown by the protein levels of cleaved-caspase3 and flow cytometry) and inflammation (shown by the decreased levels of NLRP3, p-P65 and the mRNA of several inflammatory factors). NOX4 inhibitor GLX351322 (GLX) and NOX4 kowndown by siRNA have equivalent protective effect of vaccarin in vitro. When vaccarin was administered together with GLX or NOX4 siRNA, this protective effect of vaccarin did not further increase, as indicating by the index of oxidative stress, cell viability, necroptosis and apoptosis. In conclusion, vaccarin can alleviate cisplatin-induced AKI via inhibiting NOX4.

Vaccarin alleviates endothelial inflammatory injury in diabetes by mediating miR-570-3p/HDAC1 pathway.

Vaccarin is a flavonoid glycoside, which has a variety of pharmacological properties and plays a protective role in diabetes and its complications, but its mechanism is unclear. In this study, we aim to investigate whether histone deacetylase 1(HDAC1), a gene that plays a pivotal role in regulating eukaryotic gene expression, is the target of miR-570-3p in diabetic vascular endothelium, and the potential molecular mechanism of vaccarin regulating endothelial inflammatory injury through miR-570-3p/HDAC1 pathway. The HFD and streptozotocin (STZ) induced diabetes mice model, a classical type 2 diabetic model, was established. The aorta of diabetic mice displayed a decrease of miR-570-3p, the elevation of HDAC1, and inflammatory injury, which were alleviated by vaccarin. Next, we employed the role of vaccarin in regulating endothelial cells miR-570-3p and HDAC1 under hyperglycemia conditions in vitro. We discovered that overexpression of HDAC1 counteracted the inhibitory effect of vaccarin on inflammatory injury in human umbilical vein endothelial cells (HUVECs). Manipulation of miRNA levels in HUVECs was achieved by transfecting cells with miR-570-3p mimic and inhibitor. Overexpression of miR-570-3p could decrease the expression of downstream components of HDAC1 including TNF-α, IL-1ß, and malondialdehyde, while increasing GSH-Px activity in HUVECs under hyperglycemic conditions. Nevertheless, such phenomenon was completely reversed by miR-570-3p inhibitor, and administration of miR-570-3p inhibitor could block the inhibition of vaccarin on HDAC1 and inflammatory injury. Luciferase reporter assay confirmed the 3'- UTR of the HDAC1 gene was a direct target of miR-570-3p. In summary, our findings suggest that vaccarin alleviates endothelial inflammatory injury in diabetes by mediating miR-570-3p/HDAC1 pathway. Our study provides a new pathogenic link between deregulation of miRNA expression in the vascular endothelium of diabetes and inflammatory injury and provides new ideas, insights, and choices for the scope of application and medicinal value of vaccarin and some potential biomarkers or targets in diabetic endothelial dysfunction and vascular complications.

Vaccarin enhances intestinal barrier function in type 2 diabetic mice.

AIMS: Hyperglycemia and insulin resistance drive intestinal barrier dysfunction in type 2 diabetes (T2DM). Vaccarin, the main active component in the semen of traditional Chinese medicine Vaccaria has a definite effect on T2DM mice. The purpose of this study was to investigate whether vaccarin can enhance the intestinal barrier function in T2DM. MAIN METHODS: The T2DM mice model was established by streptozocin and high-fat diet. Vaccarin at a dose of 1 mg/kg/day was administered. We evaluated the effects of vaccarin on gut microbiota and intestinal barrier function by 16S rRNA sequencing, Western blot, quantitative fluorescent PCR (qPCR), and morphological observation. Moreover, we constructed a single layer of the human intestinal epithelium model to determine the effect of vaccarin in vitro. RESULTS: The experimental results showed that vaccarin alleviated inflammatory mediators in serum and intestinal tissue of mice (P < 0.05), which may depend on the improvement of tight junctions and gut microbiota (P < 0.05). Activation of extracellular regulated protein kinases (Erk1/2) stimulated myosin light chain kinase (MLCK). By inhibiting ERK expression (P < 0.05), vaccarin had similar effects to ERK inhibitors. In addition, the regulation of tight junction barriers also involved the abovementioned pathways in vivo. CONCLUSION: Vaccarin could protect the intestinal barrier by inhibiting the ERK/MLCK signaling pathway and modulate the composition of the microbiota. These results suggested that vaccarin may be an effective candidate for improving intestinal barrier changes in T2DM.

Vaccarin promotes proliferation of and milk synthesis in bovine mammary epithelial cells through the Prl receptor-PI3K signaling pathway.

Semen Vaccariae, the seed of Vaccaria segetalis, is traditionally used in East Asian countries for the treatment of breast milk deficiency, but the underlying molecular mechanism has not been discovered yet. The present study assessed the stimulatory effect of vaccarin, one of the major constituents of Semen Vaccariae, on proliferation of and milk synthesis in bovine mammary epithelial cells (BMECs) and explored the corresponding molecular mechanism. Vaccarin affected cell proliferation and milk fat and protein synthesis in a concentration-dependent manner, with the best stimulatory effects at 0.5 µg/ml concentration. Vaccarin (0.5 µg/ml) had the similar effects as prolactin (Prl, 0.5 µg/ml) on cell proliferation, milk fat and protein synthesis, expression of Cyclin D1, phosphorylation of mechanistic target of rapamycin (mTOR), and expression and maturation of sterol regulatory element binding protein 1c (SREBP-1c). Vaccarin stimulated these signaling pathways via the Prl receptor-phosphatidyl inositol 3-kinase (PI3K) signaling. Vaccarin also concentration-dependently stimulated expression of the Prl receptor, with the best effects at 0.5 µg/ml concentration. In summary, we demonstrate that vaccarin promotes proliferation of and milk synthesis in BMECs through the Prl receptor-PI3K signaling, suggesting that vaccarin might be the main active component promoting milk production of BMECs in Semen Vaccariae.

Vaccarin prevents ox-LDL-induced HUVEC EndMT, inflammation and apoptosis by suppressing ROS/p38 MAPK signaling.

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial-mesenchymal transition (EndMT), inflammation and apoptosis in endothelial cells play crucial roles in the progression of cardiovascular diseases including atherosclerosis. Vaccarin is a flavonoid glycoside from vaccariae semen associated with powerful cardiovascular protective effects. However, the effects of vaccarin on human umbilical vein endothelial cells (HUVEC) injury in response to ox-LDL remain unknown. Herein, we showed that treatment with vaccarin significantly suppressed ox-LDL-induced HUVEC inflammation, EndMT and apoptosis. Mechanistically, the HUVECs exposed to ox-LDL exhibited enlarged reactive oxygen species (ROS) production and p38 MAPK phosphorylation, which was counteracted by vaccarin. Importantly, ROS activator hydrogen peroxide (H2O2) and p38 MAPK activator anisomycin pretreatment prevent the protective effect of vaccarin on endothelial injury induced by ox-LDL. Our study suggested that vaccarin impeded ox-LDL-triggered HUVEC inflammation, EndMT and apoptosis via inhibition of ROS/p38 MAPK signaling pathway. Vaccarin may have a therapeutic effect on endothelial injury-related disorders.

Vaccaria n-Butanol Extract Lower the Production of Proinflammatory Cytokines and the Infection Risk of T. spiralis In Vivo.

INTRODUCTION: Trichinellosis is a severe zoonosis involving the activation of inflammatory cells, accompanied by the prominent expressions of proinflammatory cytokines in the host. Semen vaccariae, the seeds of Vaccaria segetalis (Neck.) Garcke. ex Asch. (Caryophyllaceae), is a famous traditional herb that is rich in vaccaria n-butanol extract (VNE). Vaccarin is one major active component of VNE, and it is reported in the treatment of stranguria disease. Hypaphorine is another main active component of VNE and has good anti-inflammatory effect, whereas the potential bioactivity of VNE in trichinellosis treatment is still unknown. MATERIALS AND METHODS: This study was designed to evaluate the potential anthelmintic and anti-inflammatory activity of VNE toward T. spiralis infection. ICR mice were used to assess the effect of VNE on repression larvae and adult worms in vivo. Immunohistochemistry analysis was performed to evaluate the expression levels of IL-1ß, IL-6, TNF-α, and COX-2. RESULTS: Our results showed that VNE could effectively depress the expressions of proinflammatory cytokines, including IL-1ß, IL-6, TNF-α, and COX-2. The adult worms were decreased by 79.53%, while the muscle larvae were diminished by 77.70% as compared to the control. CONCLUSION: These results demonstrated that VNE may be a promising therapeutic agent against the inflammation and diseases caused by T. spiralis infection.

Vaccarin ameliorates insulin resistance and steatosis by activating the AMPK signaling pathway.

Destructive glucose and lipid metabolism in the liver is a crucial characteristic of type 2 diabetes mellitus (T2DM), eventually leading to insulin resistance and subsequent hyperglycemia and hyperlipidemia. Vaccarin is an active flavonoid glycoside associated with various biological functions, but its effects on glucose and lipid metabolic disorder in T2DM are still unclear. In this study, glucosamine (GlcN) and free fatty acids (FFAs, oleate/palmitate, 2:1 ratio) were applied to mimic insulin resistance and lipid deposition in HepG2 cells, respectively. Type 2 diabetic mice were induced using a high-fat diet (HFD) together with streptozotocin (STZ). GlcN stimulation was found to upregulate glucose production and gluconeogenesis but downregulate glycogen synthesis and phosphorylation of adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) in HepG2 cells, abnormal changes that were reversed by vaccarin. Furthermore, lipid accumulation was enhanced, but AMPK was inactivated in FFAs-exposed HepG2 cells, issues that were rectified by vaccarin treatment. These ameliorative effects of vaccarin on insulin resistance and steatosis were eliminated by AMPK inhibitor Compound C. In type 2 diabetic mice, chronic vaccarin administration decreased fasting blood glucose and lipid levels in both serum and the liver, and improved insulin sensitivity and steatosis in the liver. Taken together, these results suggest that vaccarin attenuates insulin resistance and steatosis by activating the AMPK signaling pathway.

Vaccarin protects human microvascular endothelial cells from apoptosis via attenuation of HDAC1 and oxidative stress.

Vaccarin (VAC), an active flavonoid glycoside from vaccariae semen, exhibits extensive biological activities including vascular endothelial cell protective effects. Histone deacetylase1 (HDAC1) is an epigenetic regulator in cellular apoptosis. In this study, we evaluated the protective effects of VAC on high glucose (HG)-induced cell apoptosis in human microvascular endothelial cells (HMEC-1). The levels of reactive oxygen species, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were measured. Expressions of HDAC1, Bax, Bcl-2, caspase-3 and cleaved caspase-3 were detected with western blot. Flow cytometry was used to determine cell apoptosis and cell cycle. We found that HG treatment decreased cell vitality, upregulated HDAC1 protein level, promoted reactive oxygen species production, induced cell cycle arrest and cell apoptosis in HMEC-1 cells, which were all rectified by VAC. Both scavenging reactive oxygen species and inhibition of HDAC1 alleviated the apoptosis of HMEC-1 cells in response to HG. Pretreatment with VAC prevented HG-stimulated reactive oxygen species generation and HDAC1 expression in HMEC-1 cells. Taken together, these data suggested that VAC protected against HG-induced endothelial cell apoptosis via inhibition of reactive oxygen species accumulation and HDAC1 expression. VAC may be a potential therapeutic agent for treatment of diabetes mellitus (DM)-related endothelial dysfunction.

Bacterial cellulose and bacterial cellulose-vaccarin membranes for wound healing.

Bacterial cellulose (BC) and bacterial cellulose-vaccarin (BC-Vac) membranes were successfully produced in large scale. BC was synthesized by Gluconacetobacter xylinum. BC-Vac membranes were prepared by immersing BC in vaccarin solution. The surface morphologies of BC and BC-Vac membranes were examined by a scanning electron microscope (SEM) and an atomic force microscopy (AFM). The images showed that BC-Vac exhibited the characteristic 3D nanofibrillar network of BC matrix but there was adhesion between fibers. The mechanical properties of BC and BC-Vac membranes were evaluated and the results indicated that the adding of drug vaccarin into the BC membranes increased the malleability indicated by the increment in elongation at break compared with BC. Fourier transform infrared spectroscopy (FTIR) analysis was conducted to confirm the incorporation of vaccarin in BC-Vac and investigate the hydroxyl interactions between BC and drug vaccarin. Cell viability and cell attachment studies demonstrated that BC and BC-Vac membranes had no cytotoxicity and could be a good carrier for cell growth. The wound healing performance was examined in vivo by rat skin models. Histological observations revealed that wounds treated with BC-Vac epithelialized and regenerated faster than treated with BC. Therefore, BC-Vac was considered as a potential candidate for wound dressing materials.