Usnic acid and its derivatives, a group of organic molecules with great importance, are characteristic to lichens, possessing pharmacological activities such as anti-virus, anti-bacteria, anti-humor, anti-inflammatory, analgesic, and anaesthetic effects. Many of them have been widely used as medicine, but also bring side effects such as dermatitis and liver damages. In the past decades, great efforts by isolation, organic synthesis, and structure modification methods were put on discovery of UA derivatives with higher biological activities or less side effects. This paper describes herein the most progress on natural sources, isolation and structure elucidation, structural characteristics, synthesis and modification results, pharmacological activities and toxicities of UA and its derivatives, hopefully to provide valuable reference for further research.
Benzofurans ; chemistry ; pharmacology ; Biological Products ; Lichens ; chemistry

Salvianolic acid B(Sal B) is the main water-soluble component of Salvia miltiorrhiza Bunge. Studies have found that Sal B has a good protective effect on blood vessels. Sal B can protect endothelial cells by anti-oxidative stress, inducing autophagy, inhibiting endoplasmic reticulum stress(ERS), inhibiting endothelial inflammation and adhesion molecule expression, inhibiting endothelial cell permeability, anti-thrombosis, and other ways. In addition, Sal B can alleviate endothelial cell damage caused by high glucose(HG). For vascular smooth muscle cell(VSMC), Sal B can reduce the synthesis and secretion of inflammatory factors by inhibiting cyclooxygenase. It can also play a vasodilatory role by inhibiting Ca~(2+) influx. In addition, Sal B can inhibit VSMC proliferation and migration, thereby alleviating vascular stenosis. Sal B also inhibits lipid deposition in the subendothelium, inhibits macrophage conversion to foam cells, and reduces macrophage apoptosis, thereby reducing the volume of subendothelial lipid plaques. For some atherosclerosis(AS) complications, such as peripheral artery disease(PAD), Sal B can promote angiogenesis, thereby improving ischemia. It should be pointed out that the conclusions obtained from different experiments are not completely consistent, which needs further research. In addition, previous pharmacokinetics showed that Sal B was poorly absorbed by oral administration, and it was unstable in the stomach, with a large first-pass effect in the liver. Sal B had fast distribution and metabolism in vivo and short drug action time. These affect the bioavailability and biological effects of Sal B, and the development of clinically valuable Sal B non-injectable delivery systems remains a great challenge.
Endothelial Cells ; Oxidative Stress ; Benzofurans/pharmacology* ; Lipids

OBJECTIVE: To determine whether salvianolic acid B (Sal B) exerts protective effects on diabetic peripheral neuropathy by attenuating apoptosis and pyroptosis. METHODS: RSC96 cells were primarily cultured with DMEM (5.6 mmol/L glucose), hyperglycemia (HG, 125 mmol/L glucose) and Sal B (0.1, 1, and 10 µ mol/L). Cells proliferation was measured by 3-(4, 5-cimethylthiazol-2-yl)-2, 5-dilphenyltetrazolium bromide assay. Reactive oxygen species (ROS) generation and apoptosis rate were detected by flow cytometry analysis. Western blot was performed to analyze the expressions of poly ADP-ribose polymerase (PARP), cleaved-caspase 3, cleaved-caspase 9, Bcl-2, Bax, NLRP3, ASC, and interleukin (IL)-1β. RESULTS: Treatment with HG at a concentration of 125 mmol/L attenuated cellular proliferation, while Sal B alleviated this injury (P<0.05). In addition, Sal B inhibited HG-induced ROS production and apoptosis rate (P<0.05). Furthermore, treatment with Sal B down-regulated HG-induced PARP, cleaved-caspase 3, cleaved-caspase 9, Bax, NLRP3, ASC, and IL-1β expression, but mitigated HG-mediated down-regulation of Bcl-2 expression (P<0.05). CONCLUSION Sal B may protect RSC96 cells against HG-induced cellular injury via the inhibition of apoptosis and pyroptosis activated by ROS.
Apoptosis ; Benzofurans/pharmacology* ; Oxidative Stress ; Pyroptosis ; Reactive Oxygen Species/metabolism*

The difference between three representative components of total salvianolic acids in pharmacodynamic activity were compared by three different pharmacological experiments: HUVECs oxidative damage experiment, 4 items of blood coagulation in vitro experiment in rabbits and experimental myocardial ischemia in rats. And the effects of contribution rate of each component were calculated by multi index comprehensive evaluation method based on CRITIC weights. The contribution rates of salvianolic acid B, rosmarinic acid and Danshensu were 28.85%, 30.11%, 41.04%. Apparent oil/water partition coefficient of each representative components of total salvianolic acids in n-octyl alcohol-buffer was tested and the total salvianolic acid components were characterized based on a combination of the approach of self-defined weighting coefficient with effects of contribution rate. Apparent oil/water partition coefficient of total salvianolic acids was 0.32, 1.06, 0.89, 0.98, 0.90, 0.13, 0.02, 0.20, 0.56 when in octanol-water/pH 1.2 dilute hydrochloric acid solution/ pH 2.0, 2.5, 5.0, 5.8, 6.8, 7.4, 7.8 phosphate buffer solution. It provides a certain reference for the characterization of components.
Animals ; Benzofurans ; chemistry ; pharmacology ; Cinnamates ; chemistry ; pharmacology ; Depsides ; chemistry ; pharmacology ; Lactates ; chemistry ; pharmacology ; Male ; Rabbits ; Rats ; Rats, Sprague-Dawley ; Solubility

OBJECTIVETo observe the contraction effect of endothelin-1 (ET-1) on human hepatic stellate cells (HSCs) and the inhibition of salianic-acid B (SA-B) on ET-1, to explore the acting link and the possible mechanism.

METHODSHSC were isolated from human normal liver tissue by enzyme digestion and Nycondenz density gradient centrifugation. The contraction of ET-1 on passage HSCs and the intervention of SA-B with three doses (low-, middle-, and high-) on the contraction were observed by collagen gel contraction. ET-1 and SA-B were directly added to the serum-free medium of HSCs, then calcium ion concentration was detected by laser scanning confocal microscope.

RESULTSCollagen gel contraction experiments showed that ET-1 could induce the contraction of HSC directly (P < 0.01). Three doses of SA-B significantly inhibited the contraction effects of ET-1 on HSCs (all P < 0.01). After adding the ET-1, HSCs morphology changed obviously with the number of cells decreased. However, SA-B inhibited the changes. Laser scanning confocal microscope experiments revealed that ET-1 stimulated the transiently rapid increase of intracellular calcium ion concentration, and the effects was obviously inhibited when SA-B was added.

CONCLUSIONSSA-B could inhibit the contraction of HSCs induced by ET-1, and its mechanism might be related to the lowing of free calcium ion concentration in HSCs. This anti-contraction effect of SA-B is perhaps one of the mechanisms of its anti-fibrosis and anti-portal hypertension effects.

Benzofurans ; pharmacology ; Cells, Cultured ; Endothelin-1 ; antagonists & inhibitors ; Hepatic Stellate Cells ; cytology ; Humans ; Isometric Contraction ; drug effects

In order to study the effects of Ca2+ in the biosynthesis of salvianolic acid B (Sal B) induced by salicylic acid (SA) in the young seedlings of Salvia miltiorrhiza, we used confocal laser scanning microscopy and high performance liquid chromatography to measure the change of relative fluorescence intensity of Ca2+ and the contents of Sal B induced by SA before and after the application of extracellular calcium channel inhibitors (VP and LaCl3), intracellular calcium channel inhibitor (LiCl), as well as intracellular calmodulin antagonist (TFP). SA could induce the calcium burst, and the Ca2+ peak could last to 2-3 min in the guard cells of S. miltiorrhiza, which prompted the biosynthesis of Sal B after the Ca2+ burst. Both Vp or LaCl3, and LiCl or TFP could inhibit the burst of Ca2+ and the biosynthesis of Sal B. The above results demonstrated that Ca2+ from the extracellular and the intracellular calcium store regulate the biosynthesis of Sal B elicited by salicylic acid in S. miltiorrhiz young seedlings.
Benzofurans ; metabolism ; Calcium ; metabolism ; Plant Leaves ; metabolism ; Salicylic Acid ; pharmacology ; Salvia miltiorrhiza ; metabolism ; Seedlings ; metabolism ; Signal Transduction

OBJECTIVETo observe the effect of salvianolic acid B (SAB), an extract from Radix Salviae miltiorrhizae, on expression of leucocyte differentiation antigen 14 (CD14) in the liver tissue of experimental rats with carbon tetrachloride (CCl4)-induced liver fibrosis.

METHODSThirty SD rats were randomly divided into three groups, the model group, the treated group, and the control group. The pathological fibrosis changes in liver of rats were observed. Meantime, their liver function was detected by automatic biochemical analyzer. Serum content of endotoxin was assayed by matrix staining, and plasma content of tumor necrosis factor-alpha (TNF-alpha) was detected by radioimmunoassay. mRNA and protein expressions of CD14 in the liver tissue were measured using reverse transcriptional-polymerase chain reaction and immunohistochemistry respectively.

RESULTSAll the laboratory parameters, including liver function, degree of liver fibrosis, serum endotoxin levels, plasma TNF-alpha contents, and CD14 mRNA and protein expressions in the model group were higher than those in the control group (all P<0.01). All the aforesaid indices were lowered more in the treated group than in the model group (all P<0.01).

CONCLUSIONSSAB could antagonize the CCl4, induced liver fibrosis in rats. Its mechanism of action was possibly correlated with its effects on down-regulating hepatic CD14 expression and blocking the endotoxin signal transduction pathway.

Animals ; Benzofurans ; pharmacology ; Lipopolysaccharide Receptors ; metabolism ; Liver ; drug effects ; metabolism ; Liver Cirrhosis, Experimental ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effect of salvianolic-acid B (SA-B) on epithelia-mesenchymal transition in human renal proximal tubular cells (HK2), induced by transforming growth factor beta1 (TGF-beta1).

METHODEpithelia-mesenchymal transition (EMT) was induced with TGF-beta1 in HK2 cultured in vitro. Different concentrations (2, 5, 10, 20 microg x L(-1)) and stimulant periods (12, 24, 48 h) were tried to find the perfect condition for EMT. At the same time bone morphogenetic protein-7 (BMP-7, positive control) and the SA-B intervention were given to observe their effect on EMT. Western blot and immunofluorescent microscopy were used to analyze the expression of E-cadherin and alpha-smooth muscle actin (alpha-SMA) in HK2.

RESULTBMP-7 significantly inhibited the down-regulation of E-cadherin and the up-regulation of alpha-SMA induced by TGF-beta1 (P < 0.05), and SA-B significantly inhibited the up-regulation of alpha-SMA expression induced by TGF-beta1 (P < 0.05), but not the down-regulation of E-cadherin induced by TGF-beta1.

CONCLUSIONSA-B and BMP-7 can inhibit TGF-beta1-induced EMT in HK2. Their common role is to inhibit the up-regulation of alpha-SMA, and the effect of SA-B on the regulation of E-cadherin needs further study to be confirmed.

Benzofurans ; pharmacology ; Bone Morphogenetic Protein 7 ; pharmacology ; Cadherins ; metabolism ; Cell Differentiation ; drug effects ; Cell Line ; Epithelial Cells ; pathology ; Humans ; Mesoderm ; pathology ; Transforming Growth Factor beta1 ; pharmacology

The investigation on the stem bark of Morus wittiorum was carried out to find its chemical constituents possessing anti-oxidative activity. The isolation and purification were performed by various chromatographies such as silica gel, Sephadex LH-20, RP-C18 column chromatography and so on. Based on the spectral analysis such as NMR, MS, etc., seven 2-arylbenzofuran derivatives were identified as wittifuran D (1), wittifuran E (2), moracin C (3), moracin M (4), moracin P (5), 2-(3,5-dihydroxyphenyl)-5,6-dihydroxybenzofuran (6) and mulberroside C (7). Compounds 1-7 were isolated from this plant for the first time. Among them, 1 and 2 were new compounds. Compounds 3-7 were used to assay antioxidant activity, the inhibitory ratios of compounds 3, 4, 6, at a concentration of 1 x 10(-5) mol x L(-1), to malondialdehyde (MDA) produced during microsomal lipid peroxidation induced by ferrous-cysteine were 73%, 69% and 89% respectively.
Antioxidants ; isolation & purification ; pharmacology ; Benzofurans ; chemistry ; isolation & purification ; pharmacology ; Lipid Peroxidation ; Malondialdehyde ; chemistry ; Molecular Structure ; Morus ; chemistry ; Plant Bark ; chemistry ; Plants, Medicinal ; chemistry ; Stilbenes ; chemistry ; isolation & purification ; pharmacology

OBJECTIVETo investigate the chemical constituents of red alga Corallina pilulifera.

METHODCompounds were isolated by normal phase silica gel and Sephadex LH - 20 gel column chromatography, reverse phase HPLC and recrystallization. Their structures were elucidated by spectroscopic methods including MS, 1H-NMR, 13C-NMR, HSQC, HMBC. Cytotoxicity of the compounds was screened by using standard MTT method.

RESULTSeven compounds were isolated from red alga C. pilulifera, their structures were identified as (E) -phytol epoxide (1), phytenal (2), phytol (3), dehydrovomifoliol (4), loliolide (5), 3beta-hydroxy-5alpha, 6alpha-epoxy-7-megastigmene-9-one (6), 4-hydroxybenzaldehyde (7).

CONCLUSIONAll of the compounds were obtained from this species for the first time. These compounds were inactive (IC50 > 10 microg x mL(-1)) in the MTT assay.

Benzaldehydes ; chemistry ; isolation & purification ; pharmacology ; Benzofurans ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; drug effects ; Humans ; Phytol ; chemistry ; isolation & purification ; pharmacology ; Rhodophyta ; chemistry