Farnesoid X receptor (FXR) was considered as a promising drug target in the treatment of cholestasis, druginduced liver injury, and non-alcoholic steatohepatitis (NASH). However, the existing FXR agonists have shown different degrees of side effects in clinical trials without clear interpretation. MET-409 in clinical phase III, has been proven significantly fewer side effects than that of other FXR agonists. This may be due to the completely different structure of FEX and other non-steroidal FXR agonists. Herein, the structure-based drug design was carried out based on FEX, and the more active FXR agonist LH10 (FEX EC50 = 0,3 mu M; LH10 EC50 = 0.14 mu M)) was screened out by the comprehensive SAR studies. Furthermore, LH10 exhibited robust hepatoprotective activity on the ANIT-induced cholestatic model and APAP-induced acute liver injury model, which was even better than positive control OCA. In the nonalcoholic steatohepatitis (NASH) model, LH10 significantly improved the pathological characteristics of NASH by regulating several major pathways including lipid metabolism, inflammation, oxidative stress, and fibrosis. With the above attractive results, LH10 is worthy of further evaluation as a novel agent for the treatment of liver disorders.

Histologic spectrum studies in patients revealed fatty acid binding proteins 1 (FABP1) as a potential new target for the treatment of metabolic associated fatty liver disease. However, there is no FABP1 inhibitor has been reported except the first-in-class FABP1 inhibitor bearing acid moiety reported by our laboratory. Herein, we firstly report the structure-activity relationship of novel non-carboxylic acid FABP1 inhibitors, which resulted in the identification of the potent and selective FABP1 inhibitor 30 . The IC50 50 value of compound 30 for subtype FABP4 in the same family was greater than 80 mu M. Moreover, compound 30 significantly alleviated the hepatic steatosis in DIO mice, which is equivalent to that of clinical drug obeticholic acid. This study might be provided promising probe for the development of FABP1 inhibitors and thus can help to further elucidate the pharmacology of FABP1.

The fatty acid -binding protein 1 (FABP1) is a fatty acid transporter protein that is considered as an emerging target for metabolic diseases. Despite forceful evidence that the inhibition of FABP1 is essential for ameliorating NASH, pharmacological control and validation of FABP1 are hindered by a lack of relevant inhibitors as pharmacological tool. Therefore, the development of effective FABP1 inhibitors is a current focus of research. Herein, we firstly reported the comprehensive structure -activity relationship (SAR) study of novel FABP1 inhibitors derived from high throughput screening of our in-house library, which resulting in the identification of the optimal compound 44 (IC 50 = 4.46 +/- 0.54 mu M). Molecular docking studies revealed that 44 forms stable hydrogen bonds with amino acids around the active pocket of FABP1. Moreover, 44 alleviated the typical histological features of fatty liver in NASH mice, including steatosis, lobular inflammation, ballooning and fibrosis. Additionally, 44 has been demonstrated to have lipid metabolism regulating, anti -oxidative stress and hepatoprotective properties. This study might be provided a promising insight into the field of NASH and inspiration for the development of FABP1 inhibitors.

Human carboxylesterase 2 (hCES2A), one of the most important serine hydrolases distributed in the small intestine and colon, plays a crucial role in the hydrolysis of various prodrugs and esters. Accumulating evidence has demonstrated that the inhibition of hCES2A effectively alleviate the side effects induced by some hCES2A-substrate drugs, including delayed diarrhea caused by the anticancer drug irinotecan. Nonetheless, there is a scarcity of selective and effective inhibitors that are suitable for irinotecan-induced delayed diarrhea. Following screening of the in-house library, the lead compound 01 was identified with potent inhibition on hCES2A, which was further optimized to obtain LK-44 with potent inhibitory activity (IC50 = 5.02 ± 0.67 μM) and high selectivity on hCES2A. Molecular docking and molecular dynamics simulations indicated that LK-44 can formed stable hydrogen bonds with amino acids surrounding the active cavity of hCES2A. The results of inhibition kinetics studies unveiled that LK-44 inhibited hCES2A-mediated FD hydrolysis in a mixed inhibition manner, with a Ki value of 5.28 μM. Notably, LK-44 exhibited low toxicity towards HepG2 cells according to the MTT assay. Importantly, in vivo studies showed that LK-44 significantly reduced the side effects of irinotecan-induced diarrhea. These findings suggested that LK-44 is a potent inhibitor of hCES2A with high selectivity against hCES1A, which has potential as a lead compound for the development of more effective hCES2A inhibitors to mitigate irinotecan-induced delayed diarrhea.

Human carboxylesterase 2 (hCES2) is an enzyme that metabolizes irinotecan to SN-38, a toxic metabolite considered a significant source of side effects (lethal delayed diarrhea). The hCES2 inhibitors could block the hydrolysis of irinotecan in the intestine and thus reduce the exposure of intestinal SN-38, which may alleviate irinotecan-associated diarrhea. However, existing hCES2 inhibitors (except loperamide) are not used in clinical applications due to lack of validity or acceptable safety. Therefore, developing more effective and safer drugs for treating delayed diarrhea is urgently needed. This study identified a lead compound 1 with a novel scaffold by high-throughput screening in our in-house library. After a comprehensive structure-activity relationship study, the optimal compound 24 was discovered as an efficient and highly selective hCES2 inhibitor (hCES2: IC50 = 6.72 mu M; hCES1: IC50 > 100 mu M). Further enzyme kinetics study indicated that compound 24 is a reversible inhibitor of hCES2 with competitive inhibition mode (Ki = 6.28 mu M). The cell experiments showed that compound 24 could reduce the level of hCES2 in living cells (IC50 = 6.54 mu M). The modeling study suggested that compound 24 fitted very well with the binding pocket of hCES2 by forming multiple interactions. Notably, compound 24 can effectively treat irinotecan-induced delayed diarrhea and DSS-induced ulcerative colitis, and its safety has also been verified in subtoxic studies. Based on the overall pharmacological and preliminary safety profiles, compound 24 is worthy of further evaluation as a novel agent for irinotecan-induced delayed diarrhea.

Metabolic syndrome is a complex disease with diverse symptoms, but current pharmacological interventions have limited efficacy. Indeglitazar, a pan-agonist targeting the three-peroxisome proliferator activated receptors (PPAR), exhibits significant therapeutic effects on both diabetic and fatty liver animal models. However, its short half-life limits the in vivo efficacy, which might be attributed to the beta-oxidation of indolepropionic acid at Indeglitazar. To overcome this metabolic instability, two deuterium atoms were introduced to the alpha-position of indolepropionic acid to block the beta-oxidation. In this study, several deuterated derivatives were found to sustain PPARs activity and extend the half-life of liver microsomes. In oral glucose tolerance tests, I-1 exhibited the strongest glucose-lowering effect on ob/ob mice in this series. In db/db mice, I-1 reduced lipid levels, liver steatosis and promoted UCP1 expression in white adipose tissue. Mechanistic studies further revealed that I-1 exerts stronger effects than Indeglitazar on the regulation of genes related to lipid metabolism, mitochondrial function, and oxidative stress. Furthermore, I-1 significantly reduced liver steatosis, hepatocellular ballooning, inflammation, and fibrosis in NASH model induced by HFD + CCl4, and even exerted better therapeutic effect than that of Indeglitazar. With the above attractive efficacy, deuterated derivative I-1 is considered as a promising treatment for metabolic syndrome.

The prevalence of nonalcoholic steatohepatitis (NASH) is increasing rapidly worldwide, and NASH has become a serious problem for human health. Recently, the selective activation of the intestinal farnesoid X receptor (FXR) was considered as a more promising strategy for the treatment of NASH with lesser side effects due to reduced systemic exposure. Moreover, the inhibition of intestinal fatty acid binding protein 1 (FABP1) alleviated obesity and NASH by reducing dietary fatty acid uptake. In this study, the first-in-class intestinal restricted FXR and FABP1 dual-target modulator ZLY28 was discovered by comprehensive multiparameter optimization studies. The reduced systemic exposure of ZLY28 might provide better safety by decreasing the on- and off-target side effects in vivo. In NASH mice, ZLY28 exerted robust anti-NASH effects by inhibiting FABP1 and activating the FXR-FGF15 signaling pathway in the ileum. With the above attractive efficacy and preliminary safety profiles, ZLY28 is worthy of further evaluation as a novel anti-NASH agent.

Hyperuricemia has become a global problem and is one of the four basic metabolic diseases after hypertension, hyperlipidemia, and hyperglycemia. However, the existing drugs have undesired or serious adverse effects, such as the high risk of Stevens-Johnson syndrome for allopurinol, and the cardiovascular side effects induced by febuxostat. Therefore, it is an urgent need to develop an effective and safety agent for the treatment of hyperuricemia. The urate transporter 1 (URAT1) inhibitors have been considered as a promising uric acid-lowering agents. To improve adverse reactions caused by excessive lipophilicity and large molecular weight of existing drugs, five novel low-molecular- weight URAT1 Inhibitors were designed and synthesized by molecular hybridisation. Among them, although compound 4 showed less potent activity than the classic URAT1 inhibitor benzbromarone in vitro, compound 4 exhibited better uric acid-lowering activity than benzbromarone in vivo, which may be related to the fact that compound 4 has lower lipophilicity than benzbromarone to facilitate drug absorption. In addition, compound 4 cherishes some merits, which have a smaller molecular weight and lower lipophilicity, and superior in vitro activity than lesinurad. Generally, the results indicate that compound 4, with a good therapeutic effect, is a prospective candidate for the treatment of hyperuricemia.

Farnesoid X receptor (FXR) is considered as a promising target for the treatment of NASH. Although many non-steroidal FXR agonists have been reported, the structure types are quite scarce and mainly limited to the isoxazole scaffold derived from GW4064. Therefore, it is crucial to expand the structure types of FXR agonist to explore wider chemical space. In this study, the structure-based scaffold hopping strategy was performed by hybrid FXR agonist 1 and T0901317, which resulted in the discovery of sulfonamide FXR agonist 19. Molecular docking study reasonably explained the SAR in this series, and compound 19 fitted well with the binding pocket in a similar mode to the co-crystal ligand. In addition, compound 19 exhibited considerable selectivity against other nuclear receptors. In NASH model, compound 19 alleviated the typical histological features of fatty liver, including steatosis, lobular inflammation, ballooning, and fibrosis. Moreover, compound 19 exhibited acceptable safety profiles with no acute toxicity to major organ. These results suggested that the novel sulfonamide FXR agonist 19 might be a promising agent for the treatment of NASH.

With increased unhealthy dietary patterns and a sedentary lifestyle, the prevalence of hyperuricemia is growing rapidly, placing a tremendous burden on the public health system. Persistent hyperuricemia in extreme cases induces gout, gouty arthritis, and other metabolic diseases. Benzbromarone is a potent human urate transporter 1 (URAT1) inhibitor that is widely used as a uric acid-lowering drug. Recent studies indicated that benzbromarone can also activate farnesoid X receptor (FXR), whereas its agonistic activity on FXR is rather poor. Mounting evidence suggested that the etiology of gout is directly related to NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasomes, and FXR suppresses the expression of NLRP3 in various ways. Therefore, the dual URAT1 inhibitor and FXR agonist may exert synergistic effects on decreasing uric acid (UA) levels and inhibiting inflammation. To obtain a better dual URAT1 inhibitor and FXR agonist, we performed the structure-based drug design (SBDD) strategy to improve the FXR activation of benzbromarone by forming strong interactions with ARG331 in FXR binding pocket. All of these efforts lead to the identification of compound 4, which exerts better activity on FXR and uric acid-lowering effect than benzbromarone.

Type 2 diabetes mellitus (T2DM) is a lifelong disease that requires long-term medication to control glucose levels, and thereby long-acting drug has been clinically needed for improving medical adherence. The free fatty acid receptor 1 (FFA1) was considered as a promising target for several diseases, such as T2DM, pain and fatty liver. However, no once-weekly FFA1 agonist has been reported until now. Herein, we report the successful discovery of ZLY50, the first once-weekly FFA1 agonist with a completely new chemotype, highly agonistic activity and selectivity on FFA1. Moreover, ZLY50 has enough brain exposure to activate FFA1 in brain, and it is the first orally available FFA1 agonist with analgesic activity. Notably, the long-term anti-diabetic and anti-fatty liver effects of ZLY50 (once-weekly) were better than those of HWL-088 (once-daily), a highly potent FFA1 agonist with far stronger glucose-lowering effect than Phase 3 clinical candidate TAK-875. Further mechanism studies suggested that ZLY50 alleviates fatty liver by regulating the expressions of genes related to lipid metabolism, mitochondrial function, and oxidative stress in liver.

Abstract Background CPT-11 (irinotecan) is one of the most efficient agents used for colorectal cancer chemotherapy. However, as for many other chemotherapeutic drugs, how to minimize the side effects of CPT-11 still needs to be thoroughly described. Objectives This study aimed to develop the CPT-11-loaded DSPE-PEG 2000 targeting EGFR liposomal delivery system and characterize its targeting specificity and therapeutic effect on colorectal cancer (CRC) cells in vitro and in vivo. Results The synthesized liposome exhibited spherical shapes (84.6 ± 1.2 nm to 150.4 nm ± 0.8 nm of estimated average sizes), good stability, sustained release, and enough drug loading (55.19%). For in vitro experiments, SW620 cells treated with CPT-11-loaded DSPE-PEG2000 targeting EGFR liposome showed lower survival extended level of intracellular ROS production. In addition, it generated an enhanced apoptotic cell rate by upregulating the protein expression of both cleaved-caspase-3 and cleaved-caspase-9 compared with those of SW620 cells treated with free CPT-11. Importantly, the xenograft model showed that both the non-target and EGFR-targeted liposomes significantly inhibited tumor growth compared to free CPT-11. Conclusions Compared with the non-target CPT-11-loaded DSPE-PEG2000 liposome, CPT-11-loaded DSPE-PEG2000 targeting EGFR liposome treatment showed much better antitumor activity in vitro in vivo. Thus, our findings provide new assets and expectations for CRC targeting therapy.

Fibrosis, a chronic disease with high morbidity and mortality, is mainly characterized by excessive accumulation of extracellular matrix (ECM). At present, pathogenesis of fibrosis is incompletely understood, and there is an urgent need to develop safe and effective drugs. In this study, we designed and synthesized a series of novel small-molecule compounds through structural modification and fragment hybridization. Among them, a po-tential anti-fibrosis drug compd.1 was founded to be able to dose-dependently down-regulate ACTA2 and CTGF mRNA levels in human hepatic stellate cells (LX-2) treated with TGF-beta. In addition, compd.1 significantly improved the bridging fibrosis and collagen content in the CCl4-induced liver fibrosis mice model. Moreover, compd.1 reduced lung inflammation and fibrotic area in bleomycin-induced pulmonary fibrosis mice model. These findings suggested that compd.1 is a promising candidate for further anti-fibrosis researches, and extended chemical space might help us to explore better anti-fibrosis drug.

The free fatty acid receptor 1 (FFA1) is a promising anti-diabetic target, and many FFA1 agonists including TAK-875 and AMG-837 are reached in clinical studies. However, the excessive lipophilicity of AMG-837 (ClogP=6.81) might be a potential downside attributed to the clinical failure of AMG-837. In this study, we introduced the oxime ether moiety to replace the middle benzene of AMG-837 to reduce the lipophilicity. After comprehensive structure-activity relationship study, the optimal compound 7 was identified as a partial agonist with appropriate lipophilicity (EC50=37.6 nM, Efficacy=71 %, ClogP=4.73). Moreover, compound 7 exhibited significantly glucose-lowering effects in a dose-dependent manner, and the glucose-lowering effect was equivalent to that of TAK-875 at the dose of 20 mg/kg. In conclusion, this study provided a new series partial agonists bearing oxime ether scaffold, which is worthy for further exploration based on its excellent pharmacological activity and physicochemical property.

Hyperuricemia has become a global problem and is one of the four basic metabolic diseases after hypertension, hyperlipidemia, and hyperglycemia. While existing drugs have undesired or serious adverse effects, such as acute liver damage, cardiovascular side effects, Stevens-Johnson syndrome and so on. As a consequence, it is an urgent need to develop an effective inhibitor for urate-lowering. The inhibitor of URAT1 has been widely considered as a promising strategy for gout and hyperuricemia due to promoting the excretion of uric acid. To improve the lipophilicity of existing URAT1 inhibitors, five novel URAT1-inhibiting compounds were designed and synthesized by molecular hybrid strategy. Among them, compoun 4 (IC50 = 10.5 μM) showed significantly better uric-lowering activity than the classic URAT1 inhibitor benzbromarone (IC50 = 6.8 μM) in the mice model of acute hyperuricemia. Generally, the results indicate that compound 4 is a prospective candidate for the treatment of hyperuricemia and gout. In addition, the design and synthesis strategies used in this study also provide inspiration for the development of novel URAT1 inhibitors.

A novel one pot, metal-free, three-component domino reaction for the formation of furan derivatives has been developed from 3-phenylpropiolaldehyde, 1,3-dicarbonyl compounds and aromatic amine or aliphatic acid.

Regioselective copper-catalyzed thiolation of imidazo[1,2-a]pyridines.