The novel codrugs of Leonurine and Aspirin, compounds 545 and 503 have been synthesized and evaluated on their cardioprotective effects. Preliminary pharmacological studies showed that both compounds 545 and 503 were able to increase cell viability of hypoxia-induced H9c2 cells, and compound 545 exhibited at least ten fold potency than 503 and their parent drugs (Leonurine and Aspirin). Further mechanisms studies indicated that the cardioprotective effect of 545 due to its (1) anti-oxidative ability by increasing SOD and CAT enzymes activity and decreasing MDA content and LDH leakage rate, (2) anti-apoptosis activity by regulating apoptosis-associated proteins expression during hypoxia, (3) anti-inflammatory effect by suppression of pro-inflammatory mediators. All of these results demonstrate that compound 545 as a new class of Leonurine analogue could be a drug candidate in our further drug development studies.

Hydrogen sulfide (H2S), a colorless gas smelling of rotten egg, has long been considered a toxic gas and environment hazard. However, evidences show that H2S plays a great role in many physiological and pathological activities, and it exhibits different effects when applied at various doses. In this review, we summarize the chemistry and biomedical applications of H2S-releasing compounds, including inorganic salts, phosphorodithioate derivatives, derivatives of Allium sativum extracts, derivatives of thioaminoacids, and derivatives of antiinflammatory drugs.

In this paper, we developed a novel fluorescent probe C359 for highly selective detection of H2S over other relevant biothiols. C359 is designed to contain a thiol-specific cleavable disulfide bond. H2S-mediated the disulfide cleavage and subsequent intramolecular cyclization released the masked 7-hydroxyl coumarin, displaying a remarkable fluorescence enhancement. With the promising features in hand, C359 has been applied to detect the activity of CSE (one of H2S-producing enzyme) and build up an assay for screening CSE inhibitors. We anticipated that the enzyme assay using C359 could provide a powerful methodology for screening more potent and selective enzyme inhibitors.

Hydrogen sulfide (H2S) along with carbon monoxide and nitric oxide is an important signaling molecule that has undergone large numbers of fundamental investigations. H2S is involved in various physiological activities associated with the regulation of homeostasis, vascular contractility, pro- and anti-inflammatory activities, as well as pro- and anti-apoptotic activities etc. However, the actions of H2S are influenced by its concentration, reaction time, and cell/disease types. Therefore, H2S is a signaling molecule without definite effect. The use of existing H2S donors is limited because of the instant release and short lifetime of H2S. Thus, translational medicine involving the sustained and controlled release of H2S is of great value for both scientific and clinical uses. H2S donation can be manipulated by different ways, including where H2S is given, how H2S is donated, or the specific structures of H2S-releasing drugs and H2S donor molecules. This review briefly summarizes recent progress in research on the physiological and pathological functions of H2S and H2S-releasing drugs, and suggests hope for future investigations.

A series of novel amide and thioester conjugates between Danshensu and cysteine derivatives have been designed and synthesized based on the strategy of “medicinal chemical hybridization”. Pharmacological evaluation indicated that the amide conjugates 3a/4a/17a and thioester conjugates 6a–d exhibited obvious protective effects on H2O2-induced human umbilical vein endothelial cells (HUVECs). Pretreated with these conjugates could increase glutathione (GSH) activity and decrease malondialdehyde (MDA) level. Further study on mechanism of compound 4a revealed that it was related to its mitochondrial-protective effect and regulation of apoptosis-related proteins expression (Bax, p53, PARP, caspase-3, caspase-9 and Bcl-2). These results indicate that these Danshensu-cysteine analog conjugates possess significant cardiovascular-protective effects and merit further investigation.Graphical abstractThe synthesis and pharmacological evaluation of a series of novel amide and thioester conjugates between Danshensu and cysteine derivatives have been reported and 3a/4a/17a/6a–d demonstrated significant cardiovascular-protective effect.Highlights► A series of conjugates between Danshensu and cysteine have been synthesized. ► The bioactivity assay showed significant protective effect on H2O2-induced HUVECs. ► The mechanism may be related to their anti-oxidative and anti-apoptotic properties.

The design, synthesis and biological evaluation of novel Leonurine-cysteine analog conjugates 3,5-dimethoxy-4-(2-amino-3-prop-2-ynylsulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1a), 3,5-dimethoxy-4-(2-animo-3-allysulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1b) and 3,5-dimethoxy-4-(3-(2-chlorocarbonyl-ethyldisulfanyl)-propionyl)-benzoic acid 4-guanidino-butyl ester (2) were reported in this paper. We tested their effects on hypoxia-induced neonatal rat ventricular myocytes. Our data showed that all of them had cardioprotective effects. Both of 1a and 1b were able to modulate hydrogen sulfide production, and 1a possessed higher biological activity than 1b and 2, which indicated that there was positive correlation between conjugates and their precursors. Furthermore we illuminated that the cardioprotective mechanism of 1a were related to increase SOD and CAT activity, decrease MDA and ROS level, protect some cell organs and regulate apoptosis-associated genes and proteins expression (bcl-2 and bax) via the caspase-3 pathway in molecular level. These results indicated that 1a had the potential to be a new class of multifunctional anti-myocardial ischemia agent. Most importantly, these results provided us important clues for the further design and modification of this type of Leonurine-cysteine analog conjugates in future.Compound 1a was able to anti-oxidative stress and anti-apoptosis mainly by caspase-3 pathway.Highlights► We first reported detailed synthesis method of Leonurine-cysteine analogue conjugate. ► There was positive correlation between conjugates and their precursors. ► We first exactly pointed out that 1a protected some cell organs. ► We first exactly pointed out 1a prevented apoptosis via the caspase-3 pathway.

BODIPY-Le, a colorimetric and ratiometric fluorescent probe based on boron-dipyrromethene for selective detection sulfite ion, was investigated. Boron-dipyrromethene levulinyl ester (BODIPY-Le) is composed of an indole-based BODIPY dye and the levulinyl protective group, which could be easily and selectively deprotected by sulfites. As a result, the absorption and emission spectra show a dramatic red shift, and the development of a colorimetric and ratiometric fluorescent sulfite probe could be achieved. Besides, BODIPY-Le also exhibited prominent turn-on or turn-off type fluorogenic signaling toward sulfite ions once excited at 510 and 620 nm, respectively.

A boron-dipyrromethene-Cu2+ ensemble based colorimetric probe for detection of hydrogen sulfide in aqueous media is reported. Complex 1–Cu(II) is able to selectively sense hydrogen sulfide over other anions and thiols followed by the release of compound 1 to give a remarkable change of UV absorption in aqueous solution (HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid) buffer, 50 mM, pH 7.4, 5% DMSO).

The present study attempts to investigate the effects of S-propargyl-cysteine (SPRC), a sulfur-containing amino acid, on lipopolysaccharide (LPS)-induced inflammatory response in H9c2 cardiac myocytes. We found that SPRC prevented nuclear factor-κB (NF-κB) activation assessed by NF-κB p65 phosphorylation and IκBα degradation, suppressed LPS-induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and intracellular reactive oxygen species (ROS) production. Furthermore, incubation of H9c2 cells with SPRC induced phosphorylation of Akt in a time- and concentration-dependent manner. In addition, SPRC attenuated LPS-induced mRNA and protein expression of tumor necrosis factor-α (TNF-α), and mRNA expression of intercellular adhesion molecule-1 (ICAM-1) and inducible nitric oxide synthase (iNOS). The effects of SPRC were abolished by cystathionine γ-lyase [CSE-an enzyme that synthesizes hydrogen sulfide (H2S)] inhibitor, dl-propargylglycine (PAG), SPRC-induced Akt phosphorylation and TNF-α release was also abolished by the phosphoinositide 3-kinase (PI3K) inhibitor LY294002. Furthermore, SPRC also increased LPS-induced down-regulation expression of CSE and H2S level in H9c2 cells. PAG abolished SPRC-induced up-regulation of H2S level. Therefore, we concluded that SPRC produced an anti-inflammatory effect in LPS-stimulated H9c2 cells partly through the CSE/H2S pathway by impairing IκBα/NF-κB signaling and by activating PI3K/Akt signaling pathway.

The synthesis and biological evaluation of novel leonurine–SPRC conjugate, 3,5-dimethoxy-4-(2-amino-3-prop-2-ynylsulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1) is reported in this Letter. It is designed to improve the pharmacology efficiency by combining leonurine with S-propargyl-l-cysteine (SPRC), a cysteine analog, via a phenolic hydroxyl ester bond, which could be readily hydrolyzed to release bioactive leonurine and SPRC. Pharmacological evaluation has shown that 1 possesses potent cardioprotective effect against hypoxia-induced neonatal rat ventricular myocytes damage at lower molar concentration (10-fold less than leonurine required and 100-fold less than SPRC required). The mechanism is in partial related to improve hydrogen sulfide production, anti-oxidative stress and anti-apoptosis.The synthesis and biological evaluation of novel leonurine–SPRC conjugate, 3,5-dimethoxy-4-(2-amino-3-prop-2-ynylsulfanyl-propionyl)-benzoic acid 4-guanidino-butyl ester (1) is reported in this Letter. It is designed to improve the pharmacology efficiency by combining leonurine with S-propargyl cysteine (SPRC), a cysteine analog, via a phenolic hydroxyl ester bond, which could be readily hydrolyzed to release bioactive leonurine and SPRC. Pharmacological evaluation has shown that 1 possesses potent cardioprotective effect against hypoxia-induced neonatal rat ventricular myocytes damage at lower molar concentration (10-fold less than leonurine required and 100-fold less than SPRC required). The mechanism is in partial related to improve hydrogen sulfide production, anti-oxidative stress and anti-apoptosis.

Corticotropin-releasing factor (CRF) and cholecystokinin (CCK), two highly colocalized neuropeptides, have been linked to the etiology of stress-related anxiety disorders. Recent evidence points to the possibility that some of the anxiogenic effects of the central CCK system take place through interplay with the CRF system. The aim of the present study was to examine the effects of chronic, mild activation of CRF receptor 1 (CRF1) on the central CCK system of the C57BL/6J mouse. As shown by in situ hybridization, real-Time PCR and immunohistochemistry, 5 days of intracerebroventricular (i.c.v.) injections of a subeffective dose (2.3 pmol) of cortagine, a CRF1-selective agonist, resulted in an increase in CCK mRNA levels and CCK2 receptor immunoreactivity in several brain regions, such as amygdala and hippocampus, known to be involved in the regulation of anxiety. Mice with elevated endogenous central CCK tone exhibited significantly higher anxiety-like behaviors in the open-field task and elevated plus maze, and enhanced conditioned fear. These behavioral changes were reversed by i.c.v. administration of the CCK2-selective antagonist LY225910, after 5 days of priming with cortagine. Under the same conditions, the intraperitoneal administration of the CRF1 antagonist antalarmin was ineffective. This result indicated that once the CCK system was sensitized by prior CRF1 activation, it exhibited its anxiogenic effects, without influence by CRF1, possibly because of its observed downregulation. In sum, our results provide a novel model for the interaction of the CRF and CCK systems contributing to the development of hypersensitive emotional circuitry.

The synthesis and bioactivities of Danshensu derivatives (R)-methyl 2-acetoxy-3-(3,4-diacetoxyphenyl)propanoate (1a), (R)-methyl 2-acetoxy-3-(3,4-methylenedioxyphenyl)propanoate (1b) and their racemates 7 and 10 were reported in this paper. These derivatives were designed to improve their chemical stability and liposolubility by protecting Danshensu’s phenolic hydroxyl groups with acetyl or methylene which could be readily hydrolyzed to release bioactive Danshensu. The asymmetric synthesis of 1a and 1b were achieved by catalytic hydrogenation of (Z)-methyl 2-acetoxy-3-(3,4-diacetoxyphenyl)-2-propenoate (6a) and (Z)-methyl 2-acetoxy-3-(3,4-methylenedioxyphenyl)-2-propenoate (6b) in excellent enantiomeric excesses (92% ee and 98% ee, respectively) and good yields (>89%). An unexpected intermediate product, (Z)-2-acetoxy-3-(3,4-dihydroxyphenyl)acrylic acid (4c) was obtained with high chemoselectivity in 86% yield by keeping the reaction temperature at 60 °C and its structure was identified by X-ray single crystal diffraction analysis. 1a, 1b and their racemates 7, 10 as well as 4c exhibited potent protective activities against hypoxia-induced cellular damage. The in vitro test showed that all these compounds could increase cell viability, and inhibit lipid hyperoxidation. Furthermore, 1a and 4c could inhibit apoptosis by regulating the expression of apoptosis-related molecule in gene and protein levels, up-regulating the expression of bcl-2 and down-regulating bax and caspase-3. The in vivo test indicated that 4c exhibited anti-myocardial ischemic effects featured by reducing infarction size and increasing the level of the intracellular enzymes detectable in serum. Therefore, these Danshensu derivatives may be good drug candidates for anti-myocardial ischemia therapy and merit further investigation.Two novel chiral Danshensu derivatives (1a–b) and their racemates have been designed and synthesized. Primary pharmacological evaluation showed that these Danshensu derivatives possessed potent cardioprotective activities by blocking oxidative stress and apoptotic pathways.

Variant pharmacological activities of Zanthoxylum bungeanum were determined before. The aim of this study was to assess whether Z. bungeanum could regulate lipid metabolism. The cholesterol overloading HepG2 cells induced by sterols were used as in vitro model to study lipid-lowering activities of the n-butanol (BuOH) fraction isolated from Z. bungeanum (ZBBu). Male apolipoprotein E knockout (apoE-KO) mice with high fat diet were used as in vivo model. We firstly demonstrated ZBBu had effects on reversed lipid accumulation, decreased apoB and enhanced apoA1 secretion. It increased the amount of low density lipoprotein receptor (LDLR) protein, also significantly inhibited the expression of SREBP-1 and SREBP-2's target molecule (hydroxy methylglutaryl coenzyme A reductase, HMGCR), which might be active in stimulation of RCT. And the expression of genes involved in RCT, such as CYP27A1, LXR-α, ABCG1, was promoted by ZBBu. Furthermore, ZBBu could reduce serum TC, TG levels in apoE-KO mice. Our study indicated that ZBBu could regulate the lipid metabolism through increasing the amount of low density lipoprotein receptor (LDLR) and inducing the expression of genes involved in RCT.

•SPRC blocks IL-1β-mediated migration and invasion of MH7A cells.•SPRC reduces inflammatory response in rats with adjuvant induced arthritis.•SPRC inhibits inflammatory mediators by activation CSE-H2S.•SPRC activates the Nrf2/ARE antioxidant pathway in RA.•SPRC enters cells through LAT1 transporters.Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder. Hydrogen sulfide (H2S), the third physiological gasotransmitter, is well recognized as an anti-inflammatory mediator in various inflammatory conditions. Herein, we explored the protective effects of S-propargyl-cysteine (SPRC, also known as ZYZ-802), an endogenous H2S modulator, on RA and determined the underlying mechanisms. In the present study, SPRC concentration-dependently attenuated inflammatory mediator expression, reactive oxidase species generation, and the expression and activity of matrix metalloproteinases (MMP)-9 in interleukin (IL)-1β-induced human rheumatoid fibroblast-like synoviocytes MH7A. In addition, SPRC blocked IL-1β-mediated migration and invasion of MH7A cells. As expected, the protective effects of SPRC were partially abrogated by DL-propargylglycine (PAG, a H2S biosynthesis inhibitor). In vivo study also demonstrated that SPRC treatment markedly ameliorated the severity of RA in adjuvant-induced arthritis rats, and this effect was associated with the inhibition of inflammatory response. We further identified that SPRC remarkably induced heme oxygenase-1 expression associated with the degradation of Kelch-like ECH-associated protein 1 (Keap1) and nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2); this effect was attributed to the sulfhydrylation of the cysteine residue of Keap1. Our data demonstrated for the first time that SPRC, an endogenous H2S modulator, exerted anti-inflammatory properties in RA by upregulating the Nrf2-antioxidant response element (ARE) signaling pathway.Download full-size image

Leonurine, an active alkaloid of Traditional Chinese Medicine Herba leonuri, displayed cardioprotective effects by anti-oxidative and anti-apoptotic activities in vitro and in vivo. Herein, we explored the effects and possible mechanisms of leonurine on lipopolysaccharide (LPS)-induced inflammatory responses in human umbilical vein endothelial cells (HUVEC). We found that leonurine pretreatment concentration-dependently attenuated LPS-induced mRNA expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, and monocyte chemoattractant protein-1. Meanwhile, LPS-mediated expression/release of ICAM-1, VCAM-1, and cyclooxygenase-2, and tumor necrosis factor-α was also reduced by leonurine. In addition, we confirmed that leonurine suppressed degradation of IκBα and phosphorylation of nuclear factor-κB (NF-κB) p65 as well as production of intracellular reactive oxygen species in a concentration dependent manner. Furthermore, the cytoprotective enzyme heme oxygenase-1 could be upregulated in leonurine-treated HUVEC. Our present results indicated leonurine exerted beneficial effects in inflammatory conditions partly through inhibition of reactive oxygen species and NF-κB signaling pathways.

•SPRC can against cardiac hypoxia/re-oxygenation injury.•In isolated papillary muscles, SPRC can attenuated the apoptosis cause by H/R.•In isolated myocytes, it can recovery the cell function after H/R.•SPRC exerts protective effects by reducing Ca2+ overload.•These protect effects can partly block by the CSE inhibitor PAG.S-Propargyl-l-cysteine (SPRC, also named as ZYZ-802) is a new compound synthesized in our lab. We investigated whether SPRC has exerted protective effects against cardiac hypoxia/re-oxygenation (H/R) and also explored its mechanisms. In our study, isolated ventricular myocytes were subject to a simulated hypoxia solution for 30 min to induce cell injury. Intracellular concentration of Ca2+ ([Ca2+]i) was measured using specific dyes and detected by digital imaging apparatus. Apoptotic cells were evaluated by TUNEL assay. Intervention with SPRC (10 μM) 30 min before hypoxia, can significantly attenuate the apoptosis of isolated papillary muscles resulting from the H/R injury and protect morphology of the muscles. In isolated ventricular myocytes, SPRC considerably improved left ventricular functional recovery. SPRC also suppressed the increase of ([Ca2+]i) during hypoxia stage. By measuring the calcium transient of the cell we concluded that SPRC can preserve the RyR and SERCA activities and improve Ca2+ handling during the H/R. Furthermore, the protective effect of SPRC can be partly blocked by CSE inhibitor PAG.