The GPR40 novel agonist SZZ15-11 improves non-alcoholic fatty liver disease by activating the AMPK pathway and restores metabolic homeostasis in diet-induced obese mice.

AIM: Non-alcoholic fatty liver is the most common cause of chronic liver disease. GPR40 is a potential therapeutic target for energy metabolic disorders. GPR40 is a potential therapeutic target for energy metabolic disorders. SZZ15-11 is a newly synthesized GPR40 agonist. In this study, we estimate the potency of SZZ15-11 in fatty liver treatment. METHODS: In vivo, diet-induced obese (DIO) mice received SZZ15-11 (50 mg/kg) and TAK875 (50 mg/kg) for 6 weeks. Blood glucose and lipid, hepatocyte lipid and liver morphology were analysed. In vitro, HepG2 cells and GPR40-knockdown HepG2 cells induced with 0.3 mM oleic acid were treated with SZZ15-11. Triglyceride and total cholesterol of cells were measured. At the same time, the AMPK pathway regulating triglycerides and cholesterol esters synthesis was investigated via western blot and quantitative polymerase chain reaction in both liver tissue and HepG2 cells. RESULTS: SZZ15-11 was found to not only attenuate hyperglycaemia and hyperlipidaemia but also ameliorate fatty liver disease in DIO mice. At the same time, SZZ15-11 decreased triglyceride and total cholesterol content in HepG2 cells. Whether examined in the liver of DIO mice or in HepG2 cells, SZZ15-11 upregulated AMPKα phosphorylation and then downregulated the expression of the cholesterogenic key enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase and inhibited acetyl-CoA carboxylase activity. Furthermore, SZZ15-11 promotes AMPK activity via [cAMP]i accumulation. CONCLUSION: This study confirmed that SZZ15-11, a novel GPR40 agonist, improves hyperlipidaemia and fatty liver, partially via Gs signalling and the AMPK pathway in hepatocytes.

Design, synthesis and biological evaluation of exiguamine A analogues as IDO1 inhibitors.

A series of exiguamine A analogues were designed and synthesized via 15 steps. Their inhibitory activities against IDO1 were tested and the structure-activity relationships were studied. Most compounds exhibited potent IDO1 inhibitory activities with IC50 values at the level of 10-7-10-8 M. Compound 21f was the most potent IDO1 inhibitor with an IC50 value of 65.3 nM, which was comparable with the positive control drug epacadostat (IC50 = 46 nM). Moreover, compound 21f showed higher selectivity for IDO1 over tryptophan 2,3-dioxygenase (TDO) and no cytotoxicity at its effective concentration, rending it justifiable for further optimization and evaluation.

Synthesis and cytotoxicity of (-)-homo-renieramycin G and its derivatives.

(-)-Homo-renieramycin G and its twenty derivatives were prepared from l-tyrosine methyl ester via a multi-step route. Their cytotoxicities were tested against four human cancer cell lines (A549, HeLa, KB and BGC-823). (-)-Renieramycin G and (-)-homo-renieramycin G showed comparable cytotoxicity against these four cancer cell lines, which indicated that the expansion of ring C from the six-membered 1,4-piperazinone to the seven-membered 1,4-diazepanone had no obvious impact on the cytotoxicity. Compound 42 with methyl side chain and compounds 38-41 with heterocyclic aromatic side chains at C-23 exhibited the most potent cytotoxicity with the IC50 values at the level of 10-6 M.

Design, synthesis and cytotoxicity of novel hexacyclic saframycin-ecteinascidin analogs.

Two series of novel hexacyclic skeletons and their thirty-four derivatives were prepared from l-tryptophan and l-DOPA. The cytotoxicities of these compounds were tested against four human cancer cell lines HCT-116, HepG2, BGC-823 and A2780. Compounds with the tetrahydro-ß-carboline moiety in the left-half of the hexacyclic skeleton showed more potent cytotoxicity with IC50 values in the range of 10-7-10-9 M. Compound 20 with the 4-methoxybenzamide side chain showed potent cytotoxicity towards HepG2 with an IC50 value of 1.32 nM. Compounds 29 and 30 with 2-pyridine amide and (2E)-3-(3-thifluoromethyl-phenyl)acrylic amide side chains showed selective cytotoxicity towards A2780 with IC50 values of 1.73 nM and 7 nM, respectively.

A novel specific peroxisome proliferator-activated receptor γ (PPARγ) modulator YR4-42 ameliorates hyperglycaemia and dyslipidaemia and hepatic steatosis in diet-induced obese mice.

AIMS: To evaluate a novel tetrahydroisoquinoline derivative YR4-42 as a selective peroxisome proliferator-activated receptor γ (PPARγ) modulator (SPPARM) and explore its anti-diabetic effects in vitro and in vivo. MATERIALS AND METHODS: Using two standard full PPARγ agonists rosiglitazone and pioglitazone as controls, the PPARγ binding affinity and transactivation action of YR4-42 were evaluated using biochemical and cell-based reporter gene assays. The capacity of YR4-42 to recruit coactivators of PPARγ was also assessed. The effects of YR4-42 on adipogenesis and glucose consumption and PPARγ Ser273 phosphorylation were investigated in 3T3-L1 adipocytes. The effects of YR4-42 and pioglitazone, serving as positive control, on glucose and lipids metabolism were investigated in high-fat diet-induced obese (DIO) C57BL/6J mice. The expression of PPARγ target genes involved in glucose and lipid metabolism was also assessed in vitro and in vivo. RESULTS: In vitro biochemical and cell-based functional assays showed that YR4-42 has much weaker binding affinity, transactivation, and recruitment to PPARγ of the coactivators thyroid hormone receptor-associated protein complex 220 kDa component (TRAP220) and PPARγ coactivator 1-α (PGC1α) compared to full agonists. In 3 T3-L1 adipocytes, YR4-42 significantly improved glucose consumption without a lipogenesis effect, while blocking tumour necrosis factor α-mediated phosphorylation of PPARγ at Ser273, thereby upregulating the expression of the PPARγ Ser273 phosphorylation-dependent genes. Furthermore, in DIO mice, oral administration of YR4-42 ameliorated the hyperglycaemia, with a similar insulin sensitization effect to that of pioglitazone. Importantly, YR4-42 also improved hyperlipidaemia-associated hepatic steatosis without weight gain, which avoids a major side effect of pioglitazone. Thus, YR4-42 appeared to selectively modulate PPARγ responses. This finding was supported by the gene expression analysis, which showed that YR4-42 selectively targets PPARγ-regulated genes mapped to glucose and lipid metabolism in DIO mice. CONCLUSIONS: We conclude that YR4-42 is a novel anti-diabetic drug candidate with significant advantages compared to standard PPARγ agonists. YR4-42 should be further investigated in preclinical and clinical studies.

Synthesis and cytotoxicity of novel imidazo[4,5-d]azepine compounds derived from marine natural product ceratamine A.

A series of novel imidazo[4,5-d]azepine compounds derived from marine natural product ceratamine A were designed and synthesized in 7 steps. Most compounds exhibited comparable cytotoxicity against five human cancer cell lines (HCT-116, HepG2, BGC-823, A549 and A2780) to natural product ceratamine A. Compound 1k, bearing methoxy group at C-14, C-15 and C-16, showed the best in vitro cytotoxicity, which was better than ceratamine A. The structure and activity relationships study showed that the benzyloxymethyl group on N-3 played an important role on the cytotoxicity.

Synthesis and cytotoxicity of a novel series of saframycin-ecteinascidin analogs containing tetrahydro-ß-carboline moieties.

A novel bistetrahydrocarboline heptacyclic skeleton and its twenty derivatives were prepared from l-tryptophan through a 15-step stereospecific route. The cytotoxicities of these compounds were tested against six human cancer cell lines including HCT-116, HepG2, BGC-823, MCF-7, A2780, and HT-29. Most of the derivatives with amide side chain exhibited the IC50 values at the level of 10-7 M, and a preliminary structure-activity relationship (SAR) was discussed. Both compound 30 with 2-pyridine amide side chain and compound 14 with phthalamide side chain showed the most potent and broad cytotoxicity towards all six cell lines with the IC50 values at the level of 10-8 M. Molecular docking of compound 30 indicated it bound to minor groove of DNA duplex.

Synthesis and cytotoxic activities of a series of novel N-methyl-bisindolylmaleimide amide derivatives.

A novel series of N-methyl-bisindolylmaleimides were synthesized and evaluated for their inhibitory activities against nine tumor cell lines. Some of the compounds showed an interesting activity against the tested cell lines. The most potent compounds 5e and 5j displayed antiproliferative activity with 50% inhibitory concentration values in the µM range against some tested cell lines.

Synthesis and cytotoxicity of 3-aryl acrylic amide derivatives of the simplified saframycin-ecteinascidin skeleton prepared from L-dopa.

Twenty four compounds with diversified 3-aryl acrylic amide side chains of the simplified saframycin-ecteinascidin pentacyclic skeleton were synthesized via a 14-step stereospecific route starting from L-dopa. The cytotoxicities of these compounds were tested against eight human tumor cell lines including HCT-8, BEL-7402, BGC-803, A549, A2780, MCF-7, MX-1, and MDA-MB-231. Most of these compounds exhibited potent antitumor activity, and a preliminary structure-activity relationship (SAR) was discussed. Compound 28 with 3-thiophenyl acrylic amide side chain exhibited selective cytotoxicity against MDA-MB-231 cell line with the IC50 value of 50 nM.

Asymmetric synthesis and cytotoxicity of (-)-saframycin A analogues.

(-)-Saframycin A and its nineteen analogues were prepared from L-tyrosine in 24 steps, and their structures were confirmed through NMR and HRMS. The cytotoxicities of these compounds were tested against HCT-8, BEL-7402, Ketr3, A2780, MCF-7, A549, BGC-803, Hela, HELF and KB cell lines. The IC(50) values of the cytotoxicity of most compounds were at the level of nM. Compound 7d with 2-furan amide side chain showed the most potent cytotoxicity of all these compounds with an average IC(50) value of 6.06 nM.

Asymmetric total synthesis of (-)-saframycin A from L-tyrosine.

The asymmetric total synthesis of (-)-saframycin A, a natural antitumor product of the tetrahydroisoquinoline antitumor antibiotics family, has been accomplished by employing L-tyrosine as the starting chiral building block in 24 steps for the longest linear sequence in an overall yield of 9.7%. The key steps in the synthesis involve stereoselective intermolecular and intramolecular Pictet-Spengler reactions, which induced the correct stereochemistry at C-1 and C-11, respectively. The selective protection-deprotection protocol of an amino group in the two-step transformation from intermediate 10 to 12 and a hydroxyl group in the first two steps resulted in both high selectivity and efficiency of the synthetic route.

A novel bisindolymaleimide derivative (WK234) inhibits proliferation and induces apoptosis through the protein kinase Cß pathway, in chronic myelogenous leukemia K562 cells.

WK234, a novel bisindolymaleimide derivative, was designed as a protein kinase Cß (PKCß) inhibitor. The objective of this study was to evaluate the anti-tumor activity of WK234 in the human chronic myelogenous leukemia (CML) K562 cell line and to investigate possible mechanisms of its action. The results show that WK234 inhibited K562 cell proliferation in a time- and dose-dependent manner. WK234 increased cytochrome C release and caspase-3 cleavage, which indicates that it induced apoptosis via mitochondria- and caspase-mediated pathways. Western blotting showed that PKCß1, PKCß2, and their phosphorylation levels were effectively decreased after 2-4 h of WK234 treatment. Meanwhile the phosphorylation status of PKCß downstream proteins, glycogen synthase kinase 3α/ß (GSK3α/ß) and extracellular signal-regulated kinase (ERK), were inhibited. WK234 blocked phorbol myristate acetate (PMA)-induced Ser(660) phosphorylation of PKCß2 located at the cell membrane, and increased Ser(660) PKCß2 expression within the cytoplasm and the nucleus. These results indicate that WK234 inhibited cell proliferation and induced apoptosis through suppressing the PKCß signal pathway. WK234 might be a promising candidate for the treatment of CML.

Synthesis and cytotoxicity of (-)-renieramycin G analogs.

(-)-Renieramycin G and fifteen C-22 analogs were prepared employing l-tyrosine as the chiral starting material. These analogs, along with (-)-renieramycin G itself, were evaluated in vitro for cytotoxicity against HCT-8, BEL-7402, A2780, MCF-7, A549, BGC-823, Ketr3, KB, Hela cells. The IC(50) values of most of these analogs were at the level of µM. Among these analogs, 2-thiophenecarboxylate ester derivative 17 exhibited potent cytotoxic activity against KB cell line with the IC(50) of 20 nM. From this study, it could be concluded that the C-22 side chain played an important role in the cytotoxic potency and specificity of this class of (-)-renieramycin G derivatives.

Synthesis and cytotoxicity of cis-dichloroplatinum (II) complexes of (1S,3S)-1,2,3,4-tetrahydroisoquinolines.

A series of novel cisplatin-type platinum complexes with (1S,3S)-1,2,3,4-tetrahydroisoquinolines as the ligands were synthesized as potential anticancer agents in several steps starting from commercially available l-DOPA. The cytotoxicities of these compounds were tested against HCT-8, BEL-7402, A2780, MCF-7, Hela, A549 and BGC-823 cell lines by the MTT test. Some compounds exhibited better cytotoxic activity than cisplatin. The structure-activity relationship has been revealed.

Synthesis of N-methyl-bisindolylmaleimide amino acid methyl ester conjugates and cytotoxicity study.

A novel series of N-methylbisindolylmaleimides derivatives bearing 2-acetamino acid moieties were synthesized. The cytotoxic activities of these compounds were tested in six tumor cell lines. The most potent compound 8d displayed cytotoxicity against six human tumor cell lines in the micromolar range.

Synthesis and antitumor activity of bisindolylmaleimide and amino acid ester conjugates.

A series of novel bisindolylmaleimide and natural amino acid ester conjugates were synthesized and evaluated for their inhibitory activity against six tumor cell lines. Some compounds displayed interesting cytotoxic profiles. The most active compound 8e showed inhibitory activity against several human cancer cell lines.

Synthesis and antitumor activity of simplified ecteinascidin-saframycin analogs.

Two series of simplified analogs of the ecteinascidin-saframycin type alkaloids were prepared from l-DOPA. Their in vitro antitumor activity was tested against three human cancer cell lines (HCT-8 colon carcinoma, Bel-7402 liver carcinoma, and BGC-823 gastric carcinoma). Among these compounds, the ester analogs have stronger activities than those of amide analogs in general. Among them, 1-naphthalene carboxylate ester analog 31 has the strongest activity against BGC-823 cells.

[Progress in the studies on antitumor natural product ecteinascidin-743].

The alkaloid ecteinascidin-743, isolated from the marine tunicate Ecteinascidia turbinata, binds to DNA and induces cytotoxic effects in several tumors. The drug is being codeveloped by Pharma Mar and Ortho Biotech. In May 2001 and October 2003, it was granted orphan drug status by the European Commission for soft tissue sarcoma and ovarian cancer, respectively. This paper reviews its research progress, including chemical synthesis, in vitro studies and mechanism of action, antitumor activity in vivo, toxicity, pharmacokinetics, and clinical studies.