Xa inhibitor edoxaban ameliorates hepatic ischemia-reperfusion injury via PAR-2-ERK 1/2 pathway.

Hepatic ischemia-reperfusion injury causes liver damage during surgery. In hepatic ischemia-reperfusion injury, the blood coagulation cascade is activated, causing microcirculatory incompetence and cellular injury. Coagulation factor Xa (FXa)- protease-activated receptor (PAR)-2 signaling activates inflammatory reactions and the cytoprotective effect of FXa inhibitor in several organs. However, no studies have elucidated the significance of FXa inhibition on hepatic ischemia-reperfusion injury. The present study elucidated the treatment effect of an FXa inhibitor, edoxaban, on hepatic ischemia-reperfusion injury, focusing on FXa-PAR-2 signaling. A 60 min hepatic partial-warm ischemia-reperfusion injury mouse model and a hypoxia-reoxygenation model of hepatic sinusoidal endothelial cells were used. Ischemia-reperfusion injury mice and hepatic sinusoidal endothelial cells were treated and pretreated, respectively with or without edoxaban. They were incubated during hypoxia/reoxygenation in vitro. Cell signaling was evaluated using the PAR-2 knockdown model. In ischemia-reperfusion injury mice, edoxaban treatment significantly attenuated fibrin deposition in the sinusoids and liver histological damage and resulted in both anti-inflammatory and antiapoptotic effects. Hepatic ischemia-reperfusion injury upregulated PAR-2 generation and enhanced extracellular signal-regulated kinase 1/2 (ERK 1/2) activation; however, edoxaban treatment reduced PAR-2 generation and suppressed ERK 1/2 activation in vivo. In the hypoxia/reoxygenation model of sinusoidal endothelial cells, hypoxia/reoxygenation stress increased FXa generation and induced cytotoxic effects. Edoxaban protected sinusoidal endothelial cells from hypoxia/reoxygenation stress and reduced ERK 1/2 activation. PAR-2 knockdown in the sinusoidal endothelial cells ameliorated hypoxia/reoxygenation stress-induced cytotoxicity and suppressed ERK 1/2 phosphorylation. Thus, edoxaban ameliorated hepatic ischemia-reperfusion injury in mice by protecting against micro-thrombosis in sinusoids and suppressing FXa-PAR-2-induced inflammation in the sinusoidal endothelial cells.

The anticancer potential of the CLK kinases inhibitors 1C8 and GPS167 revealed by their impact on the epithelial-mesenchymal transition and the antiviral immune response.

The diheteroarylamide-based compound 1C8 and the aminothiazole carboxamide-related compound GPS167 inhibit the CLK kinases, and affect the proliferation of a broad range of cancer cell lines. A chemogenomic screen previously performed with GPS167 revealed that the depletion of components associated with mitotic spindle assembly altered sensitivity to GPS167. Here, a similar screen performed with 1C8 also established the impact of components involved in mitotic spindle assembly. Accordingly, transcriptome analyses of cells treated with 1C8 and GPS167 indicated that the expression and RNA splicing of transcripts encoding mitotic spindle assembly components were affected. The functional relevance of the microtubule connection was confirmed by showing that subtoxic concentrations of drugs affecting mitotic spindle assembly increased sensitivity to GPS167. 1C8 and GPS167 impacted the expression and splicing of transcripts in pathways relevant to tumor progression, including MYC targets and the epithelial mesenchymal transition (EMT). Finally, 1C8 and GPS167 altered the expression and alternative splicing of transcripts involved in the antiviral immune response. Consistent with this observation, depleting the double-stranded RNA sensor DHX33 suppressed GPS167-mediated cytotoxicity on HCT116 cells. Our study uncovered molecular mechanisms through which 1C8 and GPS167 affect cancer cell proliferation as well as processes critical for metastasis.

Design, synthesis and in vitro evaluation of novel thiazole-coumarin hybrids as selective and potent human carbonic anhydrase IX and XII inhibitors.

The coumarin is one of the most promising classes of non-classical carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. In continuation of our ongoing work on search of coumarin based selective carbonic anhydrase inhibitors, a new series of 6-aminocoumarin based 16 novel analogues of coumarin incorporating thiazole (4a-p) have been synthesized and studied for their hCA inhibitory activity against a panel of human carbonic anhydrases (hCAs). Most of these newly synthesized compounds exhibited interesting inhibition constants in the nanomolar range. Among the tested compounds, the compounds 4f having 4-methoxy substitution exhibited activity at 90.9 nM against hCA XII isoform. It is noteworthy to see that all compounds were specifically and selectively active against isoforms hCA IX and hCA XII, with Ki under 1000 nM range. It is anticipated that these newly synthesized coumarin-thiazole hybrids (4a-p) may emerge as potential leads candidates against hCA IX and hCA XII as selective inhibitors compared to hCA I and hCA II.

Nitazoxanide protects against experimental ulcerative colitis through improving intestinal barrier and inhibiting inflammation.

Ulcerative colitis is a chronic disease with colonic mucosa injury. Nitazoxanide is an antiprotozoal drug in clinic. Nitazoxanide and its metabolite tizoxanide have been demonstrated to activate AMPK and inhibit inflammation, therefore, the aim of the present study is to investigate the effect of nitazoxanide on dextran sulfate sodium (DSS)-induced colitis and the underlying mechanism. Oral administration of nitazoxanide ameliorated the symptoms of mice with DSS-induced colitis, as evidenced by improving the increased disease activity index (DAI), the decreased body weight, and the shortened colon length. Oral administration of nitazoxanide ameliorated DSS-induced intestinal barrier dysfunction and reduced IL-6 and IL-17 expression in colon tissues. Mechanistically, nitazoxanide and its metabolite tizoxanide treatment activated AMPK and inhibited JAK2/STAT3 signals. Nitazoxanide and tizoxanide treatment increased caudal type homeobox 2 (CDX2) expression, increased alkaline phosphatase (ALP) activity and promoted tight junctions in Caco-2 cells. Nitazoxanide and tizoxanide treatment restored the decreased zonula occludens-1(ZO-1) and occludin protein levels induced by LPS or IL-6 in Caco-2 cells. On the other hand, nitazoxanide and tizoxanide regulated macrophage bias toward M2 polarization, as evidenced by the increased arginase-1expression in bone marrow-derived macrophages (BMDM). Nitazoxanide and tizoxanide reduced the increased IL-6, iNOS and CCL2 pro-inflammatory gene expressions and inhibited JAK2/STAT3 activation in BMDM induced by LPS. In conclusion, nitazoxanide protects against DSS-induced ulcerative colitis in mice through improving intestinal barrier and inhibiting inflammation and the underlying mechanism involves AMPK activation and JAK2/STAT3 inhibition.

In Silico Analysis of the Ga3+/Fe3+ Competition for Binding the Iron-Scavenging Siderophores of P. aeruginosa-Implementation of Three Gallium-Based Complexes in the "Trojan Horse" Antibacterial Strategy.

The emergence of multidrug-resistant (MDR) microorganisms combined with the ever-draining antibiotic pipeline poses a disturbing and immensely growing public health challenge that requires a multidisciplinary approach and the application of novel therapies aimed at unconventional targets and/or applying innovative drug formulations. Hence, bacterial iron acquisition systems and bacterial Fe2+/3+-containing enzymes have been identified as a plausible target of great potential. The intriguing "Trojan horse" approach deprives microorganisms from the essential iron. Recently, gallium's potential in medicine as an iron mimicry species has attracted vast attention. Different Ga3+ formulations exhibit diverse effects upon entering the cell and thus supposedly have multiple targets. The aim of the current study is to specifically distinguish characteristics of great significance in regard to the initial gallium-based complex, allowing the alien cation to effectively compete with the native ferric ion for binding the siderophores pyochelin and pyoverdine secreted by the bacterium P. aeruginosa. Therefore, three gallium-based formulations were taken into consideration: the first-generation gallium nitrate, Ga(NO3)3, metabolized to Ga3+-hydrated forms, the second-generation gallium maltolate (tris(3-hydroxy-2-methyl-4-pyronato)gallium), and the experimentally proven Ga carrier in the bloodstream-the protein transferrin. We employed a reliable in silico approach based on DFT computations in order to understand the underlying biochemical processes that govern the Ga3+/Fe3+ rivalry for binding the two bacterial siderophores.

Discovery and Mechanistic Studies of Dual-Target Hits for Carbonic Anhydrase IX and VEGFR-2 as Potential Agents for Solid Tumors: X-ray, In Vitro, In Vivo, and In Silico Investigations of Coumarin-Based Thiazoles.

A dual-targeting approach is predicted to yield better cancer therapy outcomes. Consequently, a series of coumarin-based thiazoles (5a-h, 6, and 7a-e) were designed and constructed as potential carbonic anhydrase (CA) and VEGFR-2 suppressors. The inhibitory actions of the target compounds were assessed against CA isoforms IX and VEGFR-2. The assay results showed that coumarin-based thiazoles 5a, 5d, and 5e can effectively inhibit both targets. 5a, 5d, and 5e cytotoxic effects were tested on pancreatic, breast, and prostate cancer cells (PANC1, MCF7, and PC3). Further mechanistic investigation disclosed the ability of 5e to interrupt the PANC1 cell progression in the S stage by triggering the apoptotic cascade, as seen by increased levels of caspases 3, 9, and BAX, alongside the Bcl-2 decline. Moreover, the in vivo efficacy of compound 5e as an antitumor agent was evaluated. Also, molecular docking and dynamics displayed distinctive interactions between 5e and CA IX and VEGFR-2 binding pockets.

C16, a PKR inhibitor, suppresses cell proliferation by regulating the cell cycle via p21 in colorectal cancer.

Double-stranded RNA-activated protein kinase R (PKR) is highly expressed in colorectal cancer (CRC). However, the role of PKR in CRC remains unclear. The aim of this study was to clarify whether C16 (a PKR inhibitor) exhibits antitumor effects and to identify its target pathway in CRC. We evaluated the effects of C16 on CRC cell lines using the MTS assay. Enrichment analysis was performed to identify the target pathway of C16. The cell cycle was analyzed using flow cytometry. Finally, we used immunohistochemistry to examine human CRC specimens. C16 suppressed the proliferation of CRC cells. Gene Ontology (GO) analysis revealed that the cell cycle-related GO category was substantially enriched in CRC cells treated with C16. C16 treatment resulted in G1 arrest and increased p21 protein and mRNA expression. Moreover, p21 expression was associated with CRC development as observed using immunohistochemical analysis of human CRC tissues. C16 upregulates p21 expression in CRC cells to regulate cell cycle and suppress tumor growth. Thus, PKR inhibitors may serve as a new treatment option for patients with CRC.

Thiazolyl-isatin derivatives: Synthesis, in silico studies, in vitro biological profile against breast cancer cells, mRNA expression, P-gp modulation, and interactions of Akt2 and VIM proteins.

The literature reports that thiazole and isatin nuclei present a range of biological activities, with an emphasis on anticancer activity. Therefore, our proposal was to make a series of compounds using the molecular hybridization strategy, which has been used by our research group, producing hybrid molecules containing the thiazole and isatin nuclei. After structural planning and synthesis, the compounds were characterized and evaluated in vitro against breast cancer cell lines (T-47D, MCF-7 and MDA-MB-231) and against normal cells (PBMC). The activity profile on membrane proteins involved in chemoresistance and tumorigenic signaling proteins was also evaluated. Among the compounds tested, the compounds 4c and 4a stood out with IC50 values of 1.23 and 1.39 µM, respectively, against the MDA-MB-231 cell line. Both compounds exhibited IC50 values of 0.45 µM for the MCF-7 cell line. Compounds 4a and 4c significantly decreased P-gp mRNA expression levels in MCF-7, 4 and 2 folds respectively. Regarding the impact on tumorigenic signaling proteins, compound 4a inhibited Akt2 in MDA-MB-231 and compound 4c inhibited the mRNA expression of VIM in MCF-7.

Design, synthesis and molecular docking of novel D-ring substituted steroidal 4,5-dihydropyrazole thiazole derivatives that act as iNOS/COX-2 inhibitors with potent anti-inflammatory activity against LPS-induced RAW264.7 macrophage cells.

Inflammation, an important biological protective response to tissue damage or microbial invasion, is considered to be an alarming signal for the progress of varied biological complications. Based on the previous reports in the literature that proved the noticeable efficacy of pyrazole and thiazole scaffold as well as nitrogen heterocyclic based compounds against acute and chronic inflammatory disease, a new set of novel D-ring substituted steroidal 4,5-dihydropyrazole thiazole derivatives were synthesized and evaluated their anti-inflammatory activities in vitro. Preliminary structure-activity relationship (SAR) analysis was conducted by their inhibitory activities against nitric oxide (NO) release in lipopolysaccharide (LPS)-induced RAW 264.7 cells, and the optimal compound 12b [3ß-hydroxy-pregn-5-en-17ß-yl-5'- (o- chlorophenyl)- 1'-(4''- phenyl -[1'', 3'']- thiazol-2''- yl) - 4',5'-dihydro - 1'H-pyrazol - 3'- yl] exhibited more potent anti-inflammatory activity than the positive control treatment methylprednisolone (MPS), with an IC50 value of 2.59 µM on NO production and low cytotoxicity against RAW 264.7 cells. In further mechanism study, our results showed that compound 12b significantly suppressed the production of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and inhibited the expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) through blocking NF-κB p65 nuclear translocation and phosphorylation of IκBα. Compound 12b also attenuated LPS-induced activation of c-Jun amino-terminal kinase (JNK) and p38 phosphorylation in RAW 264.7 cells. Molecular docking study revealed the strong binding affinity of compound 12b to the active site of the COX-2 proteins, which confirmed that compound 12b acted as an anti-inflammatory mediator. These results indicate that steroidal derivatives bearing 4,5-dihydropyrazole thiazole structure might be considered for further research and scaffold optimization in designing anti-inflammatory drugs and compound 12b might be a promising therapeutic anti-inflammatory drug candidate.

Chemical modification of Arthrobacter sarcosine oxidase by N-methylisothiazolinone reduces reactivity toward oxygen.

N-Methylisothiazolinone (MIT) is a thiol group modifier and antimicrobial agent. Arthrobacter sarcosine oxidase (SoxA), a diagnostic enzyme for assaying creatinine, loses its activity upon the addition of MIT, and its inactivation mechanism remains unclear. In this study, SoxA was chemically modified using MIT (mo-SoxA), and its structural and chemical properties were characterized. Spectral analysis data, oxygen consumption rates, and reactions were compared between intact SoxA and mo-SoxA. These demonstrate that the oxidative half-reaction toward oxygen is inhibited by MIT modification. The oxidase activity of mo-SoxA was approximately 2.1% of that of intact SoxA, and its dehydrogenase activity was approximately 4.2 times higher. The C-to-S mutants revealed that cooperative modification of 2 specific cysteine residues caused a drastic change in the enzyme reaction mode. Based on the modeled tertiary structures, the putative entrance for oxygen uptake is predicted to be blocked by the chemical modification of the 2 cysteine residues.

Synthesis of Competitive and Noncompetitive Inhibitors of Alpha-Glucosidase and Anticancer Agents.

Imidazoles and phenylthiazoles are an important class of heterocycles that demonstrate a wide range of biological activities against various types of cancers, diabetes mellitus and pathogenic microorganisms. The heterocyclic structure having oxothiazolidine moiety is an important scaffold present in various drugs, with potential for enzyme inhibition. In an effort to discover new heterocyclic compounds, we synthesized 26 new 4,5-diphenyl-1H-imidazole, phenylthiazole, and oxothiazolidine heterocyclic analogues that demonstrated potent α-glucosidase inhibition and anticancer activities. Majority of the compounds noncompetitively inhibited α-glucosidase except for two that exhibited competitive inhibition of the enzyme. Docking results suggested that the noncompetitive inhibitors bind to an apparent allosteric site on the enzyme located in the vicinity of the active site. Additionally, the analogues also exhibited significant activity against various types of cancers including non-small lung cancer. Since tubulin protein plays an important role in the pathogenesis of non-small lung cancer, molecular docking with one of the target compounds provided important clues to its binding mode. The current work on imidazoles and phenylthiazole derivatives bears importance for designing of new antidiabetic and anticancer drugs.

Identification of new 5-(2,6-dichlorophenyl)-3-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-7-carboxylic acids as p38α MAPK inhibitors: Design, synthesis, antitumor evaluation, molecular docking and in silico studies.

In pursuit of discovering novel scaffolds that demonstrate potential inhibitory activity against p38α MAPK and possess strong antitumor effects, we herein report the design and synthesis of new series of 17 final target 5-(2,6-dichlorophenyl)-3-oxo-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-7-carboxylic acids (4-20). Chemical characterization of the compounds was performed using FT-IR, NMR, elemental analyses and mass spectra of some representative examples. With many compounds showing potential inhibitory activity against p38α MAPK, two derivatives, 8 and 9, demonstrated the highest activity (>70 % inhibition) among the series. Derivative 9 displayed IC50 value nearly 2.5 folds more potent than 8. As anticipated, they both showed explicit interactions inside the kinase active site with the key binding amino acid residues. Screening both compounds for cytotoxic effects, they exhibited strong antitumor activities against lung (A549), breast (MCF-7 and MDA MB-231), colon (HCT-116) and liver (Hep-G2) cancers more potent than reference 5-FU. Their noticeable strong antitumor activity pointed out to the possibility of an augmented DNA binding mechanism of antitumor action besides their kinase inhibition. Both 8 and 9 exhibited strong ctDNA damaging effects in nanomolar range. Further mechanistic antitumor studies revealed ability of compounds 8 and 9 to arrest cell cycle in MCF-7 cells at S phase, while in HCT-116 treated cells at G0-G1 and G2/M phases. They also displayed apoptotic induction effects in both MCF-7 and HCT-116 with total cell deaths more than control untreated cells in reference to 5-FU. Finally, the compounds were tested for their anti-migratory potential utilizing wound healing assay. They induced a significant decrease in wound closure percentage after 24 h treatment in the examined cancer cells when compared to untreated control MCF-7 and HCT-116 cells better than 5-FU. In silico computation of physicochemical parameters revealed the drug-like properties of 8 and 9 with no violation to Lipinski's rule of five as well as their tolerable ADMET parameters, thus suggesting their utilization as potential future drug leads amenable for further optimization and development.

Molecular Insights into the Specific Targeting of c-MYC G-Quadruplex by Thiazole Peptides.

Stabilization of a G-quadruplex (G4) in the promotor of the c-MYC proto-oncogene leads to inhibition of gene expression, and it thus represents a potentially attractive new strategy for cancer treatment. However, most G4 stabilizers show little selectivity among the many G4s present in the cellular complement of DNA and RNA. Intriguingly, a crescent-shaped cell-penetrating thiazole peptide, TH3, preferentially stabilizes the c-MYC G4 over other promotor G4s, but the mechanisms leading to this selective binding remain obscure. To investigate these mechanisms at the atomic level, we performed an in silico comparative investigation of the binding of TH3 and its analogue TH1 to the G4s from the promotors of c-MYC, c-KIT1, c-KIT2, and BCL2. Molecular docking and molecular dynamics simulations, combined with in-depth analyses of non-covalent interactions and bulk and per-nucleotide binding free energies, revealed that both TH3 and TH1 can induce the formation of a sandwich-like framework through stacking with both the top and bottom G-tetrads of the c-MYC G4 and the adjacent terminal capping nucleotides. This framework produces enhanced binding affinities for c-MYC G4 relative to other promotor G4s, with TH3 exhibiting an outstanding binding priority. Van der Waals interactions were identified to be the key factor in complex formation in all cases. Collectively, our findings fully agree with available experimental data. Therefore, the identified mechanisms leading to specific binding of TH3 towards c-MYC G4 provide valuable information to guide the development of new selective G4 stabilizers.

Synthesis and molecular docking simulation of new benzimidazole-thiazole hybrids as cholinesterase inhibitors.

Dementia is a cognitive disturbance that is generally correlated with central nervous system diseases, especially Alzheimer's disease. The limited number of medications available is insufficient to improve the lifestyle of the patients suffering from this disease. Thus, new benzimidazole-thiazole hybrids (3-10) were designed and synthesized as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory agents. The in vitro evaluation displayed that the derivatives 4b, 4d, 5b, 6a, 7a, and 8b demonstrated dual inhibitory efficiency against both AChE with IC50 ranging from 4.55 to 8.62 µM and BChE with IC50 ranging from 3.50 to 8.32 µM. By analyzing the Lineweaver-Burk plot, an uncompetitive form of inhibition was determined for the highly active compound 4d, revealing its inhibition type. The human telomerase reverse transcriptase-immortalized retinal pigment epithelial cell line was used to ensure the safety of the most potent cholinesterase inhibitors. Furthermore, compounds 4b, 4d, 5b, 6a, 7a, and 8b were evaluated for their neuroprotective and antioxidant properties, as well as their ability to suppress COX-2. The results demonstrated that compounds 4d, 5b, and 8b presented significant neuroprotection efficiency against H2 O2 -induced damage in SH-SY5Y cells with % cell viability of 67.42 ± 7.90%, 62.51 ± 6.71%, and 72.61 ± 8.10%, respectively, while the tested candidates did not reveal significant antioxidant activity. Otherwise, compounds 4b, 6a, 7a, and 8b displayed outstanding COX-2 inhibition effects with IC50 ranging from 0.050 to 0.080 µM relative to celecoxib (IC50 = 0.050 µM). In addition, molecular docking was carried out for the potent benzimidazole-thiazole hybrids with the active sites of both AChE (PDB ID: 4EY7) and BChE (PDB code: 1P0P). The tested candidates fit well in the active sites of both portions, with docking scores ranging from -8.65 to -6.64 kcal/mol (for AChE) and -8.71 to -7.73 kcal/mol (for BChE). In silico results show that the synthesized benzimidazole-thiazole hybrids have good physicochemical and pharmacokinetic properties with no Lipinski rule violations. The preceding results exhibited that compound 4d could be used as a new template for developing more significant cholinesterase inhibitors in the future.

1,3-Thiazole Derivatives as a Promising Scaffold in Medicinal Chemistry: A Recent Overview.

The thiazole ring is a unique heterocyclic motif among heterocyclic compounds. This five-member ring with one nitrogen and one sulphur atom displays a wide array of pharmacological activities, including anti-inflammatory, antimicrobial, anticancer, antidiabetic, antiviral, etc., by acting on several targets. Its broad range of medical applications has inspired us to study this opulent heterocyclic molecule. The current review summarizes synthetic approaches for the preparation of thiazole derivatives in brief and discusses the promising biological activities of this scaffold. This review will be useful to the drug discovery community and will facilitate the synthesis and development of novel and potent thiazole derivatives, which may serve as lead molecules for the treatment of various diseases.

New pyrazolyl-thiazolidinone/thiazole derivatives as celecoxib/dasatinib analogues with selective COX-2, HER-2 and EGFR inhibitory effects: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis, molecular modelling and ADME studies.

Two new series of pyrazolyl-thiazolidinone/thiazole derivatives 16a-b and 18a-j were synthesised, merging the scaffolds of celecoxib and dasatinib. Compounds 16a, 16b and 18f inhibit COX-2 with S.I. 134.6, 26.08 and 42.13 respectively (celecoxib S.I. = 24.09). Compounds 16a, 16b, 18c, 18d and 18f inhibit MCF-7 with IC50 = 0.73-6.25 µM (dasatinib IC50 = 7.99 µM) and (doxorubicin IC50 = 3.1 µM) and inhibit A549 with IC50 = 1.64-14.3 µM (dasatinib IC50 = 11.8 µM and doxorubicin IC50 = 2.42 µM) with S.I. (F180/MCF7) of 33.15, 7.13, 18.72, 13.25 and 8.28 respectively higher than dasatinib (4.03) and doxorubicin (3.02) and S.I. (F180/A549) of 14.75, 12.96, 4.16, 7.07 and 18.88 respectively higher than that of dasatinib (S.I. = 2.72) and doxorubicin (S.I = 3.88). Derivatives 16a, 18c, 18d, 18f inhibit EGFR and HER-2 IC50 for EGFR of 0.043, 0.226, 0.388, 0.19 µM respectively and for HER-2 of 0.032, 0.144, 0.195, 0.201 µM respectively.

In-vitro antiviral screening of some thiopyranothiazoles.

Thiopyranothiazoles represent a promising class of drug-like molecules with broad pharmacological profiles. Some novel derivatives of isothiochromeno[4a,4-d]thiazole and chromeno[4',3':4,5]thiopyrano[2,3-d]thiazole were synthesized and screened against diverse viruses: coronavirus SARS, Influenza Viruses of type A and type B, Adeno- and Rhinovirus, Dengue Fever Virus, Respiratory Syncytial Virus, Rift Valley Fever Virus, Tacaribe Virus, Venezuelan Equine Encephalitis Virus, as well as Vaccinia and Human Cytomegalovirus. The antiviral activity assays revealed highly active isothiochromeno[4a,4-d]thiazole bearing phenazone fragment towards Influenza Virus type A (H1N1) with the selectivity index (SI) within 150. 5,8-Dihydro-2H-[1,3]thiazolo [5',4':5,6]thiopyrano [2,3-d][1,3]thiazol-2,6(3H)-diones showed moderate antiviral activity against influenza viruses and SARS-CoV. The obtained data indicate thiopyranothiazoles as promising class of fused 4-thiazolidinone derivatives possessing antiviral effects.

PPARß/δ activation protects against hepatic ischaemia-reperfusion injury.

BACKGROUND AND AIMS: Hepatic ischaemia/reperfusion injury (HIRI) is a pathophysiological process that occurs during the liver resection and transplantation. Reportedly, peroxisome proliferator-activated receptor ß/δ (PPARß/δ) can ameliorate kidney and myocardial ischaemia/reperfusion injury. However, the effect of PPARß/δ in HIRI remains unclear. METHODS: Mouse hepatic ischaemia/reperfusion (I/R) models were constructed for in vivo study. Primary hepatocytes and Kupffer cells (KCs) isolated from mice and cell anoxia/reoxygenation (A/R) injury model were constructed for in vitro study. Liver injury and inflammation were investigated. Small molecular compounds (GW0742 and GSK0660) and adenoviruses were used to interfere with PPARß/δ. RESULTS: We found that PPARß/δ expression was increased in the I/R and A/R models. Overexpression of PPARß/δ in hepatocytes alleviated A/R-induced cell apoptosis, while knockdown of PPARß/δ in hepatocytes aggravated A/R injury. Activation of PPARß/δ by GW0742 protected against I/R-induced liver damage, inflammation and cell death, whereas inhibition of PPARß/δ by GSK0660 had the opposite effects. Consistent results were obtained in mouse I/R models through the tail vein injection of adenovirus-mediated PPARß/δ overexpression or knockdown vectors. Furthermore, knockdown and overexpression of PPARß/δ in KCs aggravated and ameliorated A/R-induced hepatocyte injury, respectively. Gene ontology and gene set enrichment analysis showed that PPARß/δ deletion was significantly enriched in the NF-κB pathway. PPARß/δ inhibited the expression of p-IKBα and p-P65 and decreased NF-κB activity. CONCLUSIONS: PPARß/δ exerts anti-inflammatory and anti-apoptotic effects on HIRI by inhibiting the NF-κB pathway, and hepatocytes and KCs may play a synergistic role in this phenomenon. Thus, PPARß/δ is a potential therapeutic target for HIRI.

2-Aminothiazole-Flavonoid Hybrid Derivatives Binding to Tau Protein and Responsible for Antitumor Activity in Glioblastoma.

Tau protein has been described for several decades as a promoter of tubulin assembly into microtubules. Dysregulation or alterations in Tau expression have been related to various brain cancers, including the highly aggressive and lethal brain tumor glioblastoma multiform (GBM). In this respect, Tau holds significant promise as a target for the development of novel therapies. Here, we examined the structure-activity relationship of a new series of seventeen 2-aminothiazole-fused to flavonoid hybrid compounds (TZF) on Tau binding, Tau fibrillation, and cellular effects on Tau-expressing cancer cells. By spectrofluorometric approach, we found that two compounds, 2 and 9, demonstrated high affinity for Tau and exhibited a strong propensity to inhibit Tau fibrillation. Then, the biological activity of these compounds was evaluated on several Tau-expressing cells derived from glioblastoma. The two lead compounds displayed a high anti-metabolic activity on cells related to an increased fission of the mitochondria network. Moreover, we showed that both compounds induced microtubule bundling within newly formed neurite-like protrusions, as well as with defection of cell migration. Taken together, our results provide a strong experimental basis to develop new potent molecules targeting Tau-expressing cancer cells, such as GBM.

Differential Effect of ITE on the Aryl Hydrocarbon Receptor Signaling in Breast Cancer Tissue: A Histopathological Study / Efecto Diferencial de ITE en la Señalización del Receptor de Hidrocarburo de Arilo en Tejido de Cáncer de Mama: Un Estudio Histopatológico

SUMMARY: Aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is highly expressed in various types of cancers including breast cancer. However, the role of AhR with its endogenous ligand 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) on the progression of breast cancer remains poorly understood. We aimed to investigate cell proliferation and migration states in breast cancer after activating AhR with the endogenous ligand ITE. Breast cancer tissue was evaluated by cell lines, immunohistochemistry, reverse transcription-polymerase chain reaction, cell proliferation, flow cytometry, migration assays and western blot techniques. We found that AhR was widely expressed in breast cancer tissues and metastasis lymph node tissues, but not in normal tissues. The expression AhR was independent between the age, grades and TNM classifications for breast cancer tissues. ITE treatment significantly induced the activation of AhR in a time-dependent manner in both MCF-7 and T47D breast cancer cell lines. Meanwhile, ITE did not affect the cell migration but significantly suppressed the cell proliferation in estrogen receptor positive (ER+) MCF-7 andT47D cells, which probably attribute to the induction of cell cycle arrest in G1 phase and shortened S phase. Further mechanism study showed that ERK1/2 and AKT signaling were required for the activation of AhR in MCF-7 cells. These data suggest that AhR is a potential new target for treating patients with breast cancer. ITE may be more potentially used for therapeutic intervention for breast cancer with the kind of ER(+).

El receptor de hidrocarburo de arilo (AhR) es un factor de transcripción activado por ligando que se expresa en gran medida en varios tipos de cáncer, incluido el cáncer de mama. Sin embargo, el papel de AhR con su ligando endógeno 2- (1'H-indol-3'-carbonil)-tiazol-4-ácido carboxílico metil éster (ITE) en la progresión del cáncer de mama sigue siendo poco conocido. Nuestro objetivo fue investigar la proliferación celular y los estados de migración en el cáncer de mama después de activar AhR con el ligando endógeno ITE. El tejido de cáncer de mama se evaluó mediante líneas celulares, inmunohistoquímica, reacción en cadena de la polimerasa con transcriptasa inversa, proliferación celular, citometría de flujo, ensayos de migración y técnicas de transferencia Western. Descubrimos que AhR se expresó ampliamente en tejidos de cáncer de mama y en linfonodos con metástasis, pero no en tejidos normales. La expresión AhR fue independiente entre la edad, grados y clasificaciones TNM para tejidos de cáncer de mama. El tratamiento con ITE indujo significativamente la activación de AhR de manera dependiente del tiempo en las líneas celulares de cancer de mama MCF-7 y T47D. Mientras tanto, ITE no afectó la migración celular, pero suprimió significativamente la proliferación celular en células MCF-7 y T47D con receptor de estrógeno positivo (ER+), lo que probablemente se atribuye a la inducción de la detención del ciclo celular en la fase G1 y la fase S acortada. Un estudio adicional del mecanismo mostró que las señales de ERK1/2 y AKT eran necesarias para la activación de AhR en las células MCF-7. Estos datos sugieren que AhR es un nuevo objetivo potencial para el tratamiento de pacientes con cáncer de mama. ITE puede ser utilizado más potencialmente en la intervención terapéutica para el cáncer de mama con el tipo de ER (+).