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1.
J Org Chem ; 88(11): 6671-6681, 2023 Jun 02.
Article in English | MEDLINE | ID: mdl-37220021

ABSTRACT

Sulfoxides are ubiquitous in both naturally and synthetically bioactive molecules. We report herein a redox-neutral and mild approach for radical sulfinylation of redox-active esters via dual photoredox and copper catalysis, furnishing a series of functionalized sulfoxides. The reaction could accommodate a range of tertiary, secondary, and primary carboxylic acids, as well as exhibit wide functional group compatibility. The chemistry features a high degree of practicality, is scalable, and allows late-stage modification of bioactive pharmaceuticals.

2.
Pharmacology ; 106(3-4): 189-201, 2021.
Article in English | MEDLINE | ID: mdl-33621976

ABSTRACT

AIM: It has been reported that necrostatin-1 (Nec-1) is a specific necroptosis inhibitor that could attenuate programmed cell death induced by myocardial ischemia/reperfusion (I/R) injury. This study aimed to observe the effect and mechanism of novel Nec-1 analog (Z)-5-(3,5-dimethoxybenzyl)-2-imine-1-methylimidazolin-4-1 (DIMO) on myocardial I/R injury. METHODS: Male SD rats underwent I/R injury with or without different doses of DIMO (1, 2, or 4 mg/kg) treatment. Isolated neonatal rat cardiomyocytes were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) treatment with or without DIMO (0.1, 1, 10, or 100 µM). Myocardial infarction was measured by TTC staining. Cardiomyocyte injury was assessed by lactate dehydrogenase assay (LDH) and flow cytometry. Receptor-interacting protein 1 kinase (RIP1K) and autophagic markers were detected by co-immunoprecipitation and Western blotting analysis. Molecular docking of DIMO into the ATP binding site of RIP1K was performed using GLIDE. RESULTS: DIMO at doses of 1 or 2 mg/kg improved myocardial infarct size. However, the DIMO 4 mg/kg dose was ineffective. DIMO at the dose of 0.1 µM decreased LDH leakage and the ratio of PI-positive cells followed by OGD/R treatment. I/R or OGD/R increased RIP1K expression and in its interaction with RIP3K, as well as impaired myocardial autophagic flux evidenced by an increase in LC3-II/I ratio, upregulated P62 and Beclin-1, and activated cathepsin B and L. In contrast, DIMO treatment reduced myocardial cell death and reversed the above mentioned changes in RIP1K and autophagic flux caused by I/R and OGD/R. DIMO binds to RIP1K and inhibits RIP1K expression in a homology modeling and ligand docking. CONCLUSION: DIMO exerts cardioprotection against I/R- or OGD/R-induced injury, and its mechanisms may be associated with the reduction in RIP1K activation and restoration impaired autophagic flux.


Subject(s)
Autophagy/drug effects , Cardiotonic Agents/pharmacology , Cardiotonic Agents/therapeutic use , Imidazoles/chemistry , Indoles/chemistry , Myocardial Reperfusion Injury/prevention & control , Animals , Animals, Newborn , Beclin-1/metabolism , Cathepsin B/metabolism , Cathepsin L/metabolism , Cell Death/drug effects , Hemodynamics/drug effects , Male , Microtubule-Associated Proteins/metabolism , Molecular Docking Simulation , Myocardial Infarction/metabolism , Myocardial Infarction/prevention & control , Myocardial Reperfusion Injury/metabolism , Myocytes, Cardiac/drug effects , Necroptosis/drug effects , Primary Cell Culture , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/metabolism , Rats, Sprague-Dawley , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Structural Homology, Protein
3.
Sci Adv ; 6(35): eaaz5752, 2020 08.
Article in English | MEDLINE | ID: mdl-32923620

ABSTRACT

Hydrogen sulfide (H2S) is a gasotransmitter and a potential therapeutic agent. However, molecular targets relevant to its therapeutic actions remain enigmatic. Sulfide-quinone oxidoreductase (SQR) irreversibly oxidizes H2S. Therefore, SQR is assumed to inhibit H2S signaling. We now report that SQR-mediated oxidation of H2S drives reverse electron transport (RET) at mitochondrial complex I, which, in turn, repurposes mitochondrial function to superoxide production. Unexpectedly, complex I RET, a process dependent on high mitochondrial membrane potential, induces superoxide-dependent mitochondrial uncoupling and downstream activation of adenosine monophosphate-activated protein kinase (AMPK). SQR-induced mitochondrial uncoupling is separated from the inhibition of mitochondrial complex IV by H2S. Moreover, deletion of SQR, complex I, or AMPK abolishes therapeutic effects of H2S following intracerebral hemorrhage. To conclude, SQR mediates H2S signaling and therapeutic effects by targeting mitochondrial electron transport to induce mitochondrial uncoupling. Moreover, SQR is a previously unrecognized target for developing non-protonophore uncouplers with broad clinical implications.

4.
Org Lett ; 22(7): 2828-2832, 2020 04 03.
Article in English | MEDLINE | ID: mdl-32207306

ABSTRACT

Here we report a method for the site-selective intermolecular C(sp3)-H amination of carboxamides by merging transition-metal catalysis and the hydrogen atom transfer strategy. The reaction proceeds through a sequence of favorable single-electron transfer, 1,5-hydrogen atom transfer, and C-N cross-coupling steps, thus allowing access to a series of desired products. This reaction could accommodate a wide diversity of nitrogen nucleophiles as well as demonstrate excellent chemoselectivity and functional group compatibility.

5.
Org Biomol Chem ; 16(35): 6391-6394, 2018 09 11.
Article in English | MEDLINE | ID: mdl-30141823

ABSTRACT

A novel photocatalytic protocol is herein described for the preparation of functionalized phenols via radical alkylation of para-quinone methides under transition-metal-free conditions. The reaction is external oxidant free and performed at ambient temperature upon visible light irradiation, allowing the access to various desired products in satisfactory yields. The readily available 4-alkyl-1,4-dihydropyridines serve as the effective alkyl radical precursors.

6.
Neuroscience ; 390: 12-29, 2018 10 15.
Article in English | MEDLINE | ID: mdl-30076999

ABSTRACT

Receptor-interacting protein 1 kinase (RIP1K) plays a key role in necroptosis. Necrostatin-1 (Nec-1), a specific inhibitor of RIP1K, provides neuroprotection against ischemic brain injury, associating with inhibition of inflammation. Recently, our group synthesized a novel analog of Nec-1, 5-(3',5'-dimethoxybenzal)-2-thio-imidazole-4-ketone (DTIO). The present study investigated the effect of DTIO on ischemic stroke-induced brain injury in both acute and chronic phase and its underlying mechanism. In vivo, DTIO treatment reduced infarct volume and improved neurological deficits in the acute phase after permanent middle cerebral artery occlusion (pMCAO) and it also attenuated brain atrophy and promoted brain functional recovery in the chronic phase post-cerebral ischemia/reperfusion (I/R). In vitro, DTIO treatment decreased lactate dehydrogenase (LDH) leakage and necrotic cell death in the oxygen and glucose deprivation (OGD) or oxygen and glucose deprivation and reoxygenation (OGD/R)-induced neuronal or astrocytic cell injury. Simultaneously, DTIO suppressed the production and release of inflammatory cytokines, and reduced the formation of glial scar. Homology modeling analysis illustrated that DTIO had an ability of binding to RIP1K. Furthermore, immunoprecipitation analysis showed that DTIO inhibited the phosphorylation of RIP1K and decreased the interaction between the RIP1K and RIP3K. In addition, knockdown of RIP1K had neuroprotective effects and inhibited the release of proinflammatory cytokines, but didn't have a significant effect on DTIO-mediated neuroprotection. In conclusion, DTIO has protective effects on acute ischemic stroke and promotes functional recovery during chronic phase, associating with protecting ischemic neurons and astrocytes, inhibiting inflammation, and lessening the glial scar formation via inhibiting of the RIP1K.


Subject(s)
Brain Ischemia/drug therapy , Imidazoles/administration & dosage , Indoles/administration & dosage , Neuroprotective Agents/administration & dosage , Stroke/drug therapy , Animals , Astrocytes/drug effects , Astrocytes/metabolism , Brain Ischemia/complications , Brain Ischemia/metabolism , Chronic Disease/drug therapy , Imidazoles/chemistry , Indoles/chemistry , Inflammation Mediators/antagonists & inhibitors , Male , Mice, Inbred ICR , Neurons/drug effects , Neurons/metabolism , Protein Structure, Tertiary , Rats, Sprague-Dawley , Receptor-Interacting Protein Serine-Threonine Kinases/metabolism , Recovery of Function , Signal Transduction , Stroke/complications , Stroke/metabolism
7.
J Exp Clin Cancer Res ; 36(1): 144, 2017 10 16.
Article in English | MEDLINE | ID: mdl-29037225

ABSTRACT

BACKGROUND: Chemotherapy resistance remains a major challenge in cancer treatment. COX-2 (cyclooxygenase 2) is involved in drug resistance and poor prognosis of many neoplastic diseases or cancers. However, investigations identifying new modulators of COX-2 pathway and searching for new chemicals targeting these valid resistant biomarkers are still greatly needed. METHODS: HCT15, HCT-116, HT-29, COLO205, FHC, IMCE, SW480 cell lines were used to detect the expression of YAP and COX-2. Site-directed mutagenesis, luciferase reporter analysis and ChIP assay were used to test whether YAP activated COX-2 transcription through interaction with TEAD binding sites in the promoter of COX-2. Cell line models exhibiting overexpression or knockdown of some genes were generated using transfection agents. Coimmunoprecipitation was used to detect protein mutual interaction. mRNA and protein levels were measured by qRT-PCR and western blot respectively. RESULTS: Here, we reported that both YAP and COX-2 were overexpressed in colorectal cancer cells. YAP increased COX-2 expression at the level of transcription requiring intact TEAD binding sites in the COX-2 promoter. YAP conferred drug resistance through COX-2 and its related effectors such as MCL, MDR, Survivin. GCCSysm-4 (G-4), a YAP and COX-2 inhibitor, effectively inhibited both YAP and COX-2 activation, induced apoptosis and decreased viability in Taxol-resistant cells. Inhibition of YAP and COX-2 acted synergistically and more efficiently reduced the resistance of CRC cells than either of them alone. CONCLUSIONS: Our data provide new mechanisms that YAP is a new upstream regulator of COX-2 pathway and plays an important role in conferring resistance in CRC cells. G-4, targeting YAP-COX-2, may be a novel valuable strategy to combat resistance in CRC.


Subject(s)
Antineoplastic Agents/pharmacology , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Cyclooxygenase 2 Inhibitors/pharmacology , Cyclooxygenase 2/genetics , Drug Resistance, Neoplasm/drug effects , Nuclear Proteins/antagonists & inhibitors , Nuclear Proteins/metabolism , Transcription Factors/antagonists & inhibitors , Transcription Factors/metabolism , Animals , Apoptosis/drug effects , Base Sequence , Binding Sites , Cell Cycle Proteins , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Disease Models, Animal , Drug Synergism , Genes, Reporter , Humans , Male , Mice , Paclitaxel/pharmacology , Phosphorylation , Promoter Regions, Genetic , Protein Binding , Protein Transport , Response Elements , Transcriptional Activation , Xenograft Model Antitumor Assays
8.
Brain Behav Immun ; 66: 332-346, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28751019

ABSTRACT

The mechanisms underlying neuroinflammation following cerebral ischemia remain unclear. Hydrogen sulfide (H2S), a newly identified gasotransmitter, has been reported to regulate inflammation. In the current study, we investigated whether the endogenous H2S production pathway contributed to microglia-mediated neuroinflammation following stroke. We used a mouse middle cerebral artery occlusion (MCAO) model and an in vitro cellular model to mimic ischemia-induced microglial neuroinflammation. Expression of the H2S synthase cystathionine ß-synthase (CBS) and H2S synthetic activity were rapidly decreased in the ischemic brain tissue following MCAO. Consistently, when cultured microglia were polarized toward a pro-inflammatory phenotype with conditioned medium collected from neurons that had been subjected to oxygen-glucose deprivation (OGD neuron CM), they displayed reduced CBS expression and H2S production. Enhancing H2S bioavailability either by overexpressing CBS or by supplementing with exogenous H2S donors promoted a shift in microglial polarization from ischemia-induced pro-inflammatory phenotypes toward anti-inflammatory phenotypes. Mechanistically, microglia that were exposed to OGD neuron CM displayed reduced activation of AMP-activated protein kinase (AMPK), which was rescued by overexpressing CBS or by supplementing with H2S donors. Moreover, the promoting effects of H2S donors on microglial anti-inflammatory polarization were abolished by an AMPK inhibitor or CaMKKß inhibitor. Our results suggested that reduced CBS-H2S-AMPK cascade activity contributed to microglia-mediated neuroinflammation following stroke. Targeting the CBS-H2S pathway is a promising therapeutic approach for ischemic stroke.


Subject(s)
Brain Ischemia/metabolism , Cystathionine beta-Synthase/metabolism , Encephalitis/metabolism , Hydrogen Sulfide/metabolism , Microglia/metabolism , AMP-Activated Protein Kinases/metabolism , Animals , Brain Ischemia/complications , Cells, Cultured , Cerebral Cortex , Encephalitis/etiology , Gene Expression , Mice, Inbred C57BL
9.
Chem Commun (Camb) ; 53(54): 7638-7641, 2017 Jul 04.
Article in English | MEDLINE | ID: mdl-28642942

ABSTRACT

A mild and transition-metal-free protocol is herein presented for chloro-, bromo- and trifluoromethylthiotrifluoromethylation of unactivated alkenes. The easy-handling Langlois reagent, as well as N-halophthalimide and N-trifluoromethylthiosaccharin, is used in this method. In the presence of an organic photoredox catalyst N-methyl-9-mesityl acridinium, a broad range of desired products were afforded in satisfactory yields upon visible-light irradiation via a radical process.

10.
Bioorg Med Chem ; 25(1): 166-174, 2017 01 01.
Article in English | MEDLINE | ID: mdl-28340987

ABSTRACT

A series of curcumin derivatives as potent dual inhibitors of xanthine oxidase (XOD) and urate transporter 1 (URAT1) was discovered as anti-hyperuricemic agents. These compounds proved efficient effects on anti-hyperuricemic activity and uricosuric activity in vivo. More importantly, some of them exhibited proved efficient effects on inhibiting XOD activity and suppressing uptake of uric acid via URAT1 in vitro. Especially, the treatment of 4d was demonstrated to improve uric acid over-production and under-excretion in oxonate-induced hyperuricemic mice through regulating XOD activity and URAT1 expression. Docking study was performed to elucidate the potent XOD inhibition of 4d. Compound 4d may serve as a tool compound for further design of anti-hyperuricemic drugs targeting both XOD and URAT1.


Subject(s)
Curcumin/analogs & derivatives , Curcumin/therapeutic use , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/therapeutic use , Hyperuricemia/drug therapy , Organic Anion Transporters/antagonists & inhibitors , Organic Cation Transport Proteins/antagonists & inhibitors , Xanthine Oxidase/antagonists & inhibitors , Animals , Curcumin/pharmacology , Enzyme Inhibitors/pharmacology , HEK293 Cells , Humans , Hyperuricemia/metabolism , Male , Mice , Models, Molecular , Organic Anion Transporters/metabolism , Organic Cation Transport Proteins/metabolism , Uric Acid/metabolism , Xanthine Oxidase/metabolism
11.
Expert Opin Ther Pat ; 27(6): 643-656, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27998201

ABSTRACT

INTRODUCTION: Cathepsins play an important role in protein degradation and processing. Aberrant cathepsin B or L is closely associated with many serious diseases such as cancer, osteoporosis and autoimmune disorders. Therefore, development of potent and selective cathepsin B and L inhibitors has aroused much attention in recent years. Although several classes of cathepsin inhibitors are presently available, there are still some problems to solve, such as broad-spectrum inhibition to protease, specially cysteine proteases, which lead to unpredictable side effects in clinical trials. Therefore, it is very necessary to discovery new scaffolds and new application of cathepsin B and L inhibitors for developing therapeutic agents for treating diseases mediated by cathepsin B or L. Areas covered: This updated review summarizes new patents on cathepsin B and L inhibitors from 2010 to present. Expert opinion: The review gives the latest development in the area of inhibitors of cathepsin B and L, which have been considered key therapeutic targets for the development of drugs treating related diseases. This review puts emphasis on the discovery of novel small molecule inhibitors of cathepsin B and L, as well as their new application as new therapeutic agents.


Subject(s)
Cathepsin B/antagonists & inhibitors , Cathepsin L/antagonists & inhibitors , Drug Design , Animals , Autoimmune Diseases/drug therapy , Autoimmune Diseases/physiopathology , Cathepsin B/metabolism , Cathepsin L/metabolism , Humans , Molecular Targeted Therapy , Neoplasms/drug therapy , Neoplasms/pathology , Osteoporosis/drug therapy , Osteoporosis/physiopathology , Patents as Topic
12.
Bioorg Med Chem ; 24(21): 5368-5373, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27618541

ABSTRACT

Twelve novel hybrids of slowly releasing hydrogen sulfide donor ADT-OH combined with nicotinic acid were synthesized. All of their structures had been confirmed by 1H NMR, 13C NMR and MS spectra. The target compounds were evaluated for their neuroprotective effects on hippocampal neuron HT22 cells against glutamate-induced injury at the concentrations of 1-100µM with MTT assay, and their toxicity on HT22 cells untreated by glutamine at the concentration of 100µM. The active compound was further investigated for its effect on ischemic infarct volume by intraperitoneal injection at 3h after ischemia in mice models of permanent middle cerebral artery occlusion (pMCAO). The results showed that all the compounds significantly protected HT22 cells from glutamate-induced damage at most of the experimental concentrations, and had no or little neurotoxicity on normal HT22 cells at the high concentration. More importantly, compound A6 significantly reduced infarct volume in the pMCAO model. These results suggested that compound A6 may be promising for further evaluation for the intervention of cerebral ischemic injury.


Subject(s)
Brain Ischemia/drug therapy , Hydrogen Sulfide/metabolism , Nicotinic Acids/chemistry , Nicotinic Acids/pharmacology , Animals , Brain Ischemia/chemically induced , Cell Line , Cell Survival/drug effects , Disease Models, Animal , Dose-Response Relationship, Drug , Glutamic Acid , Injections, Intraperitoneal , Mice , Molecular Structure , Nicotinic Acids/administration & dosage , Structure-Activity Relationship
13.
Oncotarget ; 7(32): 52150-52165, 2016 Aug 09.
Article in English | MEDLINE | ID: mdl-27437776

ABSTRACT

Hydrogen sulfide-releasing oleanolic acid (HS-OA) is an emerging novel class of compounds and consists of an oleanolic acid (OA) and a H2S-releasing moiety. Although it exhibits improved anti-inflammatory activity, its potency in human cancers has not been understood yet. In this study, we examined the effects of HS-OA on the growth of liver cancer cell lines and the underlying mechanisms.HS-OA inhibited the growth of all four cancer cell lines studied, with potencies of 10- to 30-fold greater than that of its counterpart (OA). HS-OA induced significant apoptosis and decreased viability, clonogenic activity and migration of Hep G2 cells. Further studies showed that HS-OA resulted in the reduction of YAP expression and its downstream targets, CTGF and CYR 61, thus promoting cell apoptosis. In addition, HS-OA caused a decrease of 14-3-3γ expression, which led to Bad translocation to the mitochondria, ΔΨm loss, cytochrome c release, caspase activation and a recovery of 14-3-3γ reversed these effects induced by HS-OA.These findings indicate that YAP and 14-3-3γ are involved in HS-OA's effects on liver cancer cells and identifying HS-OA as a potential new drug candidate for cancer therapy.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/metabolism , Hydrogen Sulfide/pharmacology , Liver Neoplasms/metabolism , Oleanolic Acid/pharmacology , 14-3-3 Proteins/metabolism , Adaptor Proteins, Signal Transducing/metabolism , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Hydrogen Sulfide/chemistry , Oleanolic Acid/chemistry , Phosphoproteins/metabolism , Transcription Factors , YAP-Signaling Proteins
14.
J Enzyme Inhib Med Chem ; 31(6): 1457-63, 2016 Dec.
Article in English | MEDLINE | ID: mdl-26899462

ABSTRACT

A series of hybrids, which are composed of glycyrrhetic acid (GA) and slowly hydrogen sulfide-releasing donor ADT-OH, were designed and synthesized to develop anticancer and anti-inflammatory agents. Most of the compounds, whose inhibitory rates were comparable to or higher than those of GA and aspirin, respectively, significantly inhibited xylene-induced ear edema in mice. Especially, compound V4 exhibited the most potent inhibitory rate of 60.7%. Furthermore, preliminary structure-activity relationship studies demonstrated that 3-substituted GA derivatives had stronger anti-inflammatory activities than the corresponding 3-unsubstituted GA derivatives. In addition, anti-proliferative activities of compounds V1-9 were evaluated in three different human cancer cell lines. Compound V4 showed the most high potency against all three tumor cell lines with IC50 values ranging from 10.01 µM in Hep G2 cells to 17.8 µM in MDA-MB-231 cells, which were superior to positive GA.


Subject(s)
Glycyrrhetinic Acid/metabolism , Hydrogen Sulfide/metabolism , Animals , Cell Line, Tumor , Drug Screening Assays, Antitumor , Glycyrrhetinic Acid/analogs & derivatives , Humans , Mice , Spectrum Analysis/methods
15.
Biochem Biophys Res Commun ; 458(3): 632-638, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25684185

ABSTRACT

How hydrogen sulfide (H2S) protects against myocardial ischemia-reperfusion (I/R) injury is poorly understood. By using a slow-releasing H2S donor, we investigated if H2S protected against myocardial I/R injury by activating AMPK and restoring I/R-impaired autophagic flux. Male rats received anterior descending coronary artery occlusion followed by reperfusion. The H2S donor ADT and/or the AMPK inhibitor, compound C (CC), were administered after occlusion. Infarction was analyzed histologically. AMPK activation was assessed in the ischemic heart by analyzing phosphorylation of AMPK and S6 ribosomal protein. Autophagy was assessed by analyzing the following markers: microtubule-associated protein 1 light chain 3 (LC3) I and II, lysosome associated membrane protein-2 (LAMP-2), P62 and beclin-1. We further investigated if blocking autophagic flux with chloroquine abolished ADT cardioprotection in vivo. Myocardial I/R reduced serum H2S levels, which was elevated by ADT. ADT enhanced AMPK activation and reduced infarction following I/R, and both effects were abolished by AMPK inhibition. Myocardial I/R induced autophagosome accumulation, as evidenced by the increased ratios of LC3-II/LC3-I, upregulation of beclin-1 and P62 and reduction in LAMP-2. ADT blunted these autophagic changes induced by I/R, indicating that ADT restored I/R-impaired autophagic flux. The AMPK inhibitor CC blocked ADT effects on restoring I/R-impaired autophagy flux. Moreover, chloroquine pretreatment abolished cardioprotection of ADT and increased autophagosome accumulation in the ADT-treated heart following I/R. In conclusion, AMPK activation and subsequent restoration of I/R-impaired autophagic flux are unrecognized mechanisms underlying cardioprotective effects conferred by H2S donors.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Autophagy/drug effects , Cardiotonic Agents/therapeutic use , Enzyme Activation/drug effects , Heterocyclic Compounds, 1-Ring/therapeutic use , Hydrogen Sulfide/therapeutic use , Myocardial Reperfusion Injury/prevention & control , Thiones/therapeutic use , Animals , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/blood , Heart/drug effects , Hemodynamics , Heterocyclic Compounds, 1-Ring/administration & dosage , Heterocyclic Compounds, 1-Ring/blood , Hydrogen Sulfide/administration & dosage , Hydrogen Sulfide/blood , Male , Myocardial Reperfusion Injury/blood , Myocardial Reperfusion Injury/pathology , Myocardium/enzymology , Myocardium/pathology , Rats, Sprague-Dawley , Thiones/administration & dosage , Thiones/blood
16.
J Neurochem ; 129(5): 827-38, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24673410

ABSTRACT

By using two structurally unrelated hydrogen sulfide (H2 S) donors 5-(4-methoxyphenyl) -3H-1, 2-dithiole-3-thione (ADT) and sodium hydrosulfide (NaHS), this study investigated if H2 S protected blood-brain barrier (BBB) integrity following middle cerebral artery occlusion (MCAO). ICR mice underwent MCAO and received H2 S donors at 3 h after reperfusion. Infarction, neurological scores, brain edema, Evans blue (EB) extravasation, and tight junction protein expression were examined at 48 h after MCAO. We also investigated if ADT protected BBB integrity by suppressing post-ischemic inflammation-induced Matrix Metalloproteimase-9 (MMP9) and Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX). ADT increased blood H2 S concentrations, decreased infarction, and improved neurological deficits. Particularly, ADT reduced EB extravasation, brain edema and preserved expression of tight junction proteins in the ischemic brain. NaHS also increased blood H2 S levels and reduced EB extravasation following MCAO. Moreover, ADT inhibited expression of pro-inflammatory markers induced Nitric Oxide Synthase (iNOS) and IL-1ß while enhanced expression of anti-inflammatory markers arginase 1 and IL-10 in the ischemic brain. Accordingly, ADT attenuated ischemia-induced expression and activity of MMP9. Moreover, ADT reduced NOX-4 mRNA expression, NOX activity, and inhibited nuclear translocation of Nuclear Factor Kappa-B (NF-κB) in the ischemic brain. In conclusion, H2 S donors protected BBB integrity following experimental stroke possibly by acting through NF-κB inhibition to suppress neuroinflammation induction of MMP9 and NOX4-derived free radicals. To determine H2 S effects on blood-brain barrier (BBB) disruption following stroke, we used two structurally unrelated H2 S donors ADT and NaHS. Both ADT and NaHS remarkably protected BBB integrity following experimental stroke. The slow-releasing donor ADT also reduced post-ischemic inflammation-induced expression and activity of MMP9 and NOX4 in the ischemic brain possibly by inhibiting NF-κB activation.


Subject(s)
Blood-Brain Barrier/drug effects , Brain Ischemia/drug therapy , Brain Ischemia/pathology , Heterocyclic Compounds, 1-Ring/pharmacology , Hydrogen Sulfide/pharmacology , Neuroprotective Agents , Thiones/pharmacology , Animals , Behavior, Animal/drug effects , Blotting, Western , Brain Edema/pathology , Coloring Agents , Enzyme-Linked Immunosorbent Assay , Evans Blue , Hydrogen Sulfide/blood , Infarction, Middle Cerebral Artery/pathology , Infarction, Middle Cerebral Artery/prevention & control , Interleukin-10/metabolism , Male , Mice , Mice, Inbred ICR , NADPH Oxidases/antagonists & inhibitors , NADPH Oxidases/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Peroxidase/metabolism , Real-Time Polymerase Chain Reaction
17.
Antioxid Redox Signal ; 21(12): 1741-58, 2014 Oct 20.
Article in English | MEDLINE | ID: mdl-24624937

ABSTRACT

AIMS: The manner in which hydrogen sulfide (H2S) suppresses neuroinflammation is poorly understood. We investigated whether H2S polarized microglia to an anti-inflammatory (M2) phenotype by activating AMP-activated protein kinase (AMPK). RESULTS: Three structurally unrelated H2S donors (5-(4-hydroxyphenyl)-3H-1,2-dithiocyclopentene-3-thione [ADT-OH], (p-methoxyphenyl) morpholino-phosphinodithioic acid [GYY4137], and sodium hydrosulfide [NaHS]) enhanced AMPK activation in BV2 microglial cells in the presence and absence of lipopolysaccharide (LPS). The overexpression of the H2S synthase cystathionine ß-synthase (CBS) in BV2 cells enhanced endogenous H2S production and AMPK activation regardless of LPS stimulation. On LPS stimulation, overexpression of both ADT-OH and CBS promoted M2 polarization of BV2 cells, as evidenced by suppressed M1 and elevated M2 signature gene expression. The promoting effects of ADT-OH on M2 polarization were attenuated by an AMPK inhibitor or AMPK knockdown. Liver kinase B1 (LKB1) and calmodulin-dependent protein kinase kinase ß (CaMKKß) are upstream kinases that activate AMPK. ADT-OH activated AMPK in Hela cells lacking LKB1. In contrast, both the CaMKKß inhibitor and siRNA abolished ADT-OH activation of AMPK in LPS-stimulated BV2 cells. Moreover, the CaMKKß inhibitor and siRNA blunted ADT-OH suppression on M1 gene expression and enhancement of M2 gene expression in LPS-stimulated BV2 cells. Moreover, ADT-OH promoted M2 polarization of primary microglia in an AMPK activation- and CaMKKß-dependent manner. Finally, in an LPS-induced in vivo neuroinflammation model, both ADT-OH and NaHS enhanced AMPK activation in the brain area where microglia were over-activated on LPS stimulation. Furthermore, ADT-OH suppressed M1 and promoted M2 gene expression in this in vivo model. INNOVATION AND CONCLUSION: CaMKKß-dependent AMPK activation is an unrecognized mechanism underlying H2S suppression on neuroinflammation.


Subject(s)
AMP-Activated Protein Kinases/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Kinase/metabolism , Hydrogen Sulfide/metabolism , Neurodegenerative Diseases/metabolism , Animals , Cells, Cultured , Enzyme Activation , Inflammation/metabolism , Mice , Mice, Inbred C57BL , Microglia/metabolism
18.
Int J Mol Sci ; 15(3): 3970-88, 2014 Mar 05.
Article in English | MEDLINE | ID: mdl-24603537

ABSTRACT

The antioxidative properties of a novel curcumin analogue (2E,6E)-2,6-bis(3,5-dimethoxybenzylidene)cyclohexanone (MCH) were assessed by several in vitro models, including superoxide anion, hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and PC12 cell protection from H2O2 damage. MCH displayed superior O2•- quenching abilities compared to curcumin and vitamin C. In vitro stability of MCH was also improved compared with curcumin. Exposure of PC12 cells to 150 µM H2O2 caused a decrease of antioxidant enzyme activities, glutathione (GSH) loss, an increase in malondialdehyde (MDA) level, and leakage of lactate dehydrogenase (LDH), cell apoptosis and reduction in cell viability. Pretreatment of the cells with MCH at 0.63-5.00 µM before H2O2 exposure significantly attenuated those changes in a dose-dependent manner. MCH enhanced cellular expression of transcription factor NF-E2-related factor 2 (Nrf2) at the transcriptional level. Moreover, MCH could mitigate intracellular accumulation of reactive oxygen species (ROS), the loss of mitochondrial membrane potential (MMP), and the increase of cleaved caspase-3 activity induced by H2O2. These results show that MCH protects PC12 cells from H2O2 injury by modulating endogenous antioxidant enzymes, scavenging ROS, activating the Nrf2 cytoprotective pathway and prevention of apoptosis.


Subject(s)
Antioxidants/pharmacology , Curcumin/analogs & derivatives , Curcumin/pharmacology , Cyclohexanones/pharmacology , Plant Preparations/pharmacology , Protective Agents/pharmacology , Animals , Antioxidants/chemistry , Apoptosis/drug effects , Biphenyl Compounds/antagonists & inhibitors , Biphenyl Compounds/metabolism , Blotting, Western , Caspase 3/metabolism , Catalase/metabolism , Cell Survival/drug effects , Curcumin/chemistry , Cyclohexanones/chemistry , Free Radical Scavengers/chemistry , Free Radical Scavengers/pharmacology , Gene Expression/drug effects , Glutathione/metabolism , Hydrogen Peroxide/pharmacology , Hydroxyl Radical/antagonists & inhibitors , Hydroxyl Radical/metabolism , Lipid Peroxidation/drug effects , Molecular Structure , NF-E2-Related Factor 2/genetics , Oxidants/pharmacology , PC12 Cells , Picrates/antagonists & inhibitors , Picrates/metabolism , Plant Preparations/chemistry , Protective Agents/chemistry , Rats , Reverse Transcriptase Polymerase Chain Reaction , Superoxide Dismutase/metabolism , Superoxides/antagonists & inhibitors , Superoxides/metabolism
19.
J Sep Sci ; 37(3): 314-22, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24259446

ABSTRACT

Gardenia fruits contain valuable natural food colorants including crocins (gardenia yellow) and geniposide. In this study, a process for the enrichment of crocins and geniposide simultaneously from gardenia fruits was developed using macroporous resin and RP chromatography. The performance of eight different types of macroporous resins was evaluated. Static absorption/desorption experiments revealed that LX60 possessed optimal separating capacity. Further dynamic absorption/desorption experiments on LX60 columns were conducted to obtain the optimal parameters. After one run treatment with LX60, the content of crocin-1 in gardenia yellow reached 29.6%, while geniposide in another fraction reached 83.4%. An extract of crocins was obtained from gardenia yellow in a second-stage separation using RP medium-pressure LC, with its color value to be 756 and the content of crocin-1 reaching 60.8%. The separation process was highly efficient, low cost, and compact, which may be informative for purifications of other natural products from complex plant extracts.


Subject(s)
Carotenoids/isolation & purification , Chromatography, High Pressure Liquid/methods , Chromatography, Reverse-Phase/methods , Fruit/chemistry , Gardenia/chemistry , Iridoids/isolation & purification , Plant Extracts/isolation & purification , Carotenoids/analysis , Chromatography, High Pressure Liquid/instrumentation , Chromatography, Reverse-Phase/instrumentation , Iridoids/analysis , Plant Extracts/analysis , Porosity , Resins, Synthetic/chemistry
20.
Expert Opin Ther Pat ; 24(1): 19-27, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24083428

ABSTRACT

INTRODUCTION: Fatty acid biosynthesis is essential for the bacterial viability and growth. In recent years, ß-ketoacyl-acyl carrier protein synthase III (FabH) become an attractive new target, which catalyzes the first step of fatty acid biosynthesis, and FabH inhibitors could be potential candidates for antibacterial agents. In this review, recent advances in the research of FabH inhibitors are reviewed. AREAS COVERED: This updated review summarized new patents and articles publications on FabH inhibitors within July 2012 to June 2013. EXPERT OPINION: The review gives the latest development in the area of FabH inhibitors which aim to solve the bacterial resistance. The potent antibacterial activities of the selected compounds are probably correlated to their FabH inhibitory. Molecular docking of the most potent compound in every kind of compounds against FabH was also reviewed to explore the binding mode of the compound at the active site.


Subject(s)
3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/antagonists & inhibitors , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacterial Proteins/antagonists & inhibitors , Drug Design , Enzyme Inhibitors/pharmacology , Molecular Targeted Therapy , 3-Oxoacyl-(Acyl-Carrier-Protein) Synthase/metabolism , Animals , Anti-Bacterial Agents/chemistry , Bacteria/enzymology , Bacteria/growth & development , Bacterial Proteins/metabolism , Drug Resistance, Neoplasm , Enzyme Inhibitors/chemistry , Humans , Legislation, Drug , Molecular Docking Simulation , Molecular Structure , Patents as Topic , Structure-Activity Relationship
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