Structure−Activity Relationship Studies of Chalcone Leading to 3-Hydroxy-4,3′,4′,5′-tetramethoxychalcone and Its Analogues as Potent Nuclear Factor κB Inhibitors and Their Anticancer Activities

Quinine-chalcone hybrids as potent inhibitors of P-glycoprotein with apoptotic effects on EBC-1 cells

Chincona alkaloids extracted from the bark stem of Cinchona officinalis have been historically used to treat fever and malaria. More recently, cinchona alkaloid derivatives have been attributed to apoptotic effects in the context of cancer. Similarly, chalcones are plant-derived polyphenolic compounds with known anti-fungal, -microbial, -malarial, and -carcinogenic properties. Here, we reveal cytotoxic and antiproliferative characteristics of synthetic quinine-chalcone hybrids in human cancer cell lines. Two derivatives (AD-12 and AD-13) presented IC50 values below 2 µM in the lung squamous cell carcinoma cell line (EBC-1). Our study shows that AD-12 and AD-13 increased intracellular ROS levels and promoted caspase-3/7, and -8 activity in EBC-1 cells. These apoptotic effects were accompanied by short-term inhibition of P-gp efflux activity, while expression levels of P-gp transporters remained stable. Together, our study illustrates the potential of quinine-chalcone hybrids as novel anticancer drug candidates.

Discovery of novel dual tubulin and MMPs inhibitors for the treatment of lung cancer and overcoming drug resistance

Nowadays, hybrid molecule with dual targets activity or effect is regarded as an effective strategy for combating the drug resistance development in cancer therapy. Herein, novel of bifunctional conjugates targeting tubulin and MMPs inhibitors were synthesized. Among them, 15j exhibited robust anticancer activity in vitro and in vivo, with IC50 values of 0.154-0.296 μM against four human cancer cells and a 74.7 % (@20 mg/kg) tumor growth inhibition in vivo without obvious systemic toxicity. Mechanistic studies indicated that 15j exerted inhibitory effects on both tubulin polymerization, MMP-2 and MMP-9 activity. Moreover, 15j remarkably inhibited cell proliferation, migration and invasion, and accordingly disrupted the NF-κB signaling transduction. Furthermore, 15j effectively initiated mitochondria-dependent apoptotic pathway by causing mitochondrial dysfunction, promoting the accumulation of reactive oxygen species, and inducing DNA damage. Collectively, these results demonstrated that 15j, as a tubulin/MMPs dual-targeting inhibitor, has exhibited significant potential for the lung cancer therapy.

Chalcone Synthesis by Green Claisen-Schmidt Reaction in Cationic and Nonionic Micellar Media

In this paper, micellar-mediated synthesis of chalcones was explored. After optimization of the reaction conditions, the cationic surfactant CTAB and the nonionic one, Tween 80, were taken into consideration. Both surfactants were used to study the scope of Claisen-Schmidt reactants, and a wide scope on both aromatic aldehydes and methyl ketones was explored, obtaining from good to very good yields in most cases and thus demonstrating that the chalcones can be proficiently synthesized in micellar solutions with a wide functional group tolerability. Often, when one surfactant did not perform well, the other surfactant performed better, demonstrating that the use of different surfactants can constitute a good alternative to overcome reactivity problems. Besides, Tween 80 can be proposed as a good and greener alternative to CTAB in most cases. Some reactions gave low yields, showing that some specific improvements would be needed to address the low reactivity. The micellar medium was studied by NMR to search for information about the association of the Claisen-Schmidt reactants with the micelles and their locations within them. Diffusion Ordered Spectroscopy (DOSY) was applied to assess the interaction and the percentage of incorporation of reactants into the micelles.

Benzylidene-isophorone hybrids with strong anticancer activity

Isophorone is a cyclic ketone that has gained significant attention in the field of organic chemistry due to its versatile reactivity and structural attributes. Derivatives of isophorone offer a broad spectrum of applications ranging from pharmaceuticals to polymer chemistry. With the aim of developing novel hybrid structures based on benzylidene by combining with isophorone scaffold, we report 3 derivatives of the benzylidene-isophorone hybrids and its potent anticancer activity. In order to optimize the anticancer activity of hybrids di-substitution of -Cl group in C2 and C6 position of phenyl ring (compound1), -OCH3 group in C2 and C5 position of phenyl ring (compound2), and -OCH3 group in C2 and C3 position of phenyl ring (compound3) of benzylidene (PhCH=) moiety were made. The structure of Compounds1,2 and 3 were elucidated using spectral and XRD methods. Compounds1,2 and 3 exhibit space group P c a 21, P-1, and P 1 21/n 1 respectively. Compounds1,2 and 3 were tested for the potent anticancer activity on MDA MB-231 cell line. All the three compounds exhibit good anticancer activity on the breast cancer cells. The parent hybrid with ortho, ortho directing -Cl (1) exhibits strong antiproliferation effect (IC50 = 0.028 µM) on MDA-MB 231 cell line. However, hybrid structures with ortho, meta directing -OCH3 (2) group showed moderate effect (IC50 = 0.061 µM) and hybrid with ortho, meta directing -OCH3 (3) substitution showed the least potent anticancer activity (IC50 = 0.074 µM). The benzylidene-isophorone hybrids exhibit anticancer effects in the following order: 1 > 2 > 3.

Synthesis and Antiproliferative Effect of New Alkyne-Tethered Vindoline Hybrids Containing Pharmacophoric Fragments

In the frame of our diversity-oriented research on multitarget small molecule anticancer agents, utilizing convergent synthetic sequences terminated by Sonogashira coupling reactions, a preliminary selection of representative alkyne-tethered vindoline hybrids was synthesized. The novel hybrids with additional pharmacophoric fragments of well-documented anticancer agents, including FDA-approved tyrosine-kinase inhibitors (imatinib and erlotinib) or ferrocene or chalcone units, were evaluated for their antiproliferative activity on malignant cell lines MDA-MB-231 (triple negative breast cancer), A2780 (ovarian cancer), HeLa (human cervical cancer), and SH-SY5Y (neuroblastoma) as well as on human embryonal lung fibroblast cell line MRC-5, which served as a reference non-malignant cell line for the assessment of the therapeutic window of the tested hybrids. The biological assays identified a trimethoxyphenyl-containing chalcone-vindoline hybrid (36) as a promising lead compound exhibiting submicromolar activity on A2780 cells with a marked therapeutic window.

Novel NF-κB Inhibitor-Conjugated Pt(IV) Prodrug to Enable Cancer Therapy through ROS/ER Stress and Mitochondrial Dysfunction and Overcome Multidrug Resistance

Although cisplatin has been widely used for clinical purposes, its application is limited due to its obvious side effects. To mitigate the defects of cisplatin, here, six "multitarget prodrugs" were synthesized by linking cisplatin and NF-κB inhibitors. Notably, complex 9 demonstrated a 63-fold enhancement in the activity against A549/CDDP cells with lower toxicity toward normal LO2 cells compared to cisplatin. Additionally, complex 9 could effectively cause DNA damage, induce mitochondrial dysfunction, generate reactive oxygen species, and induce cell apoptosis through the mitochondrial pathway and ER stress. Remarkably, complex 9 effectively inhibited the NF-κB/MAPK signaling pathway and disrupted the PI3K/AKT signaling transduction. Importantly, complex 9 showed superior in vivo antitumor efficiency compared to cisplatin or the combination of cisplatin/4, without obvious systemic toxicity in A549 or A549/CDDP xenograft models. Our results demonstrated that the dual-acting mechanism endowed the complexes with high efficiency and low toxicity, which may represent an efficient strategy for cancer therapy.

Structure-based discovery of potent myosin inhibitors to guide antiparasite drug development

Monogenea, a prevalent parasite in aquaculture, poses significant threats to the industry, leading to substantial losses. Current preventive measures have proven insufficient, necessitating the development of novel and effective anti-parasitic drugs. In this investigation, we obtained the full-length myosin cDNA sequence by analyzing three-generation transcriptome data, revealing a 5817-base sequence encoding 1938 amino acids. Subsequently, we modeled and analyzed the characteristics of the secondary and tertiary of myosin, pinpointing the crucial functional region within the motor domain (amino acids 1-768). The prokaryotic expression of this domain yielded a protein of 87.44 kDa, confirmed as myosin by Western Blotting. Molecular docking identified ASN439 as the key amino acid residue involved in arctigenin and myosin binding, a result corroborated by site-directed mutagenesis, affirming the active cavity of this interaction. Chalcone and shikonin were chosen from a virtual sieve of molecular library of natural drugs based on the active cavity. Chalcone and shikonin exhibited EC50 values of 1.085 mg/L and 0.371 mg/L, respectively, with corresponding IC50 values for myosin of 0.44 mM and 0.14 mM. Given its superior activity and structure, shikonin was selected for further optimization of drug molecule design, culminating in the discovery of 1,4-naphthoquinone as a potent antiparasitic agent. This compound demonstrated an EC50 of 0.047 mg/L, LC50 of 0.23 mg/L, and a TI index of 4.893. These findings collectively highlight the potential of shikonin and 1,4-naphthoquinone as alternative compounds to control Gyrodactylus infections. Further optimization of medicinal chemistry holds promise for the development of more potent 1,4-naphthoquinone analogues, offering prospects for future anthelmintic control through combinatorial or replacement strategies.

Recent Trends in the Synthesis and Bioactivity of Coumarin, Coumarin-Chalcone, and Coumarin-Triazole Molecular Hybrids

Molecular hybridization represents a new approach in drug discovery in which specific chromophores are strategically combined to create novel drugs with enhanced therapeutic effects. This innovative strategy leverages the strengths of individual chromophores to address complex biological challenges, synergize beneficial properties, optimize pharmacokinetics, and overcome limitations associated with single-agent therapies. Coumarins are documented to possess several bioactivities and have therefore been targeted for combination with other active moieties to create molecular hybrids. This review summarizes recent (2013-2023) trends in the synthesis of coumarins, as well as coumarin-chalcone and coumarin-triazole molecular hybrids. To cover the wide aspects of this area, we have included differently substituted coumarins, chalcones, 1,2,3- and 1,2,4-triazoles in this review and considered the point of fusion/attachment with coumarin to show the diversity of these hybrids. The reported syntheses mainly relied on well-established chemistry without the need for strict reaction conditions and usually produced high yields. Additionally, we discussed the bioactivities of the reported compounds, including antioxidative, antimicrobial, anticancer, antidiabetic, and anti-cholinesterase activities and commented on their IC50 where possible. Promising bioactivity results have been obtained so far. It is noted that mechanistic studies are infrequently found in the published work, which was also mentioned in this review to give the reader a better understanding. This review aims to provide valuable information to enable further developments in this field.

Dual-targeting tumor cells hybrids derived from Pt(IV) species and NF-κB inhibitors enables cancer therapy through mitochondrial dysfunction and ER stress and overcomes cisplatin resistance

To ameliorate the defects including serious side effects and drug resistance of Pt(II) drugs (e.g., cisplatin and oxaliplatin), here a novel of "dual-prodrug" by containing Pt(II) drugs and NF-κB inhibitors were synthesized and characterized. Among them, Pt(IV) complex 11 exhibited better cytotoxic activity than other Pt(IV) complexes and the corresponding Pt(II) drugs, with IC50 values ranged from 0.31 to 0.91 μM, respectively, and also displayed low toxicity toward two normal cells HL-7702 and BEAS-2B. More importantly, complex 11 significantly reversed cisplatin resistance in A549/CDDP cells, indicating that complex 11 was able to overcome multidrug resistance. Following mechanism studies demonstrated that complex 11 significantly induced DNA damage and ROS generation, arrest the cell cycle at the G2/M stage, suppressed cell migration and intrusion, and induced cell apoptosis through activated ER stress and mitochondrial apoptosis pathway in A549 cells. Moreover, complex 11 effectively suppressed the IKKβ phosphorylation, IκBα phosphorylation and NF-κB p65 phosphorylation and nuclear translocation, leading to blocked the NF-κB signal pathway in A549 cells. In vivo tests showed that the inhibitory rate in the complex 11 reached 69.2 %, which was much higher than that of oxaliplatin (55.6 %), 1a (39.7 %) and the combination of oxaliplatin/1a (65.1 %), without causing loss in the body weight.

2'-Hydroxychalcone Induces Autophagy and Apoptosis in Breast Cancer Cells via the Inhibition of the NF-κB Signaling Pathway: In Vitro and In Vivo Studies

2'-Hydroxychalcone is a hydroxyl derivative of chalcones, which are biosynthetic precursors of flavonoids and rich in the human diet. The anticancer activity of 2'-hydroxychalcone has been reported in several cancers but remains to be investigated in breast cancer. In the current study, 2'-hydroxychalcone showed significant cytotoxicity against breast cancer cell lines MCF-7 and CMT-1211. It could inhibit breast cancer cell proliferation, migration, and invasion in vitro and suppress tumor growth and metastasis in vivo. Mechanistic investigation revealed that the NF-κB pathway was significantly inhibited by 2'-hydroxychalcone treatment accompanied by an excessive intracellular accumulation of reactive oxygen species, induction of endoplasmic reticulum stress, and activation of JNK/MAPK. In addition, 2'-hydroxychalcone elevated the autophagic levels in breast cancer cells equipped with increasing numbers of autophagy vesicles and complete autophagic flux. Finally, autophagy-dependent apoptosis was observed in 2'-hydroxychalcone-induced cell death. In conclusion, 2'-hydroxychalcone enhances the autophagic levels and induces apoptosis in breast cancer cells, which could be contributed to the inhibition of the pro-survival NF-κB signaling, indicating a promising potential for 2'-hydroxychalcone in future anticancer drug development.

Synthesis and biological evaluation of 2'-hydroxychalcone derivatives as AMPK activators

A series of 2'-hydroxychalcone derivatives with various substituents on B-ring were synthesized and evaluated for AMP-activated protein kinase (AMPK) activation activity in podocyte cells. The results displayed that hydroxy, methoxy and methylenedioxy groups on B-ring could enhance the activitiy better than O-saturated alkyl, O-unsaturated alkyl or other alkoxy groups. Compounds 27 and 29 possess the highest fold change of 2.48 and 2.73, respectively, which were higher than those of reference compound (8) (1.28) and metformin (1.88). Compounds 27 and 29 were then subjected to a concentration-response study to obtain the EC50 values of 2.0 and 4.8 µM, respectively and MTT assays also showed that cell viability was not influenced by the exposure of podocytes to compounds 27 and 29 at concentrations up to 50 μM. In addition, compound 27 was proved to activate AMPK via calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-dependent pathway without affecting intracellular calcium levels. The computational study showed that the potent compounds exhibited stronger ligand-binding strength to CaMKKβ, particularly compounds 27 (-8.4 kcal/mol) and 29 (-8.0 kcal/mol), compared to compound 8 (-7.5 kcal/mol). Fragment molecular orbital (FMO) calculation demonstrated that compound 27 was superior to compound 29 due to the presence of methyl group, which amplified the binding by hydrophobic interactions. Therefore, compound 27 would represent a promising AMPK activator for further investigation of the treatment of diabetes and diabetic nephropathy.

CuAAC-Based Synthesis, Copper-Catalyzed Aldehyde-Forming Hydrolytic Fission and Antiproliferative Evaluation of Novel Ferrocenoylamino-Substituted Triazole-Tethered Quinine-Chalcone Hybrids

A series of novel triazole-tethered ferrocenoylamino-substituted cinchona-chalcone hybrids along with two representative benzoylamino-substituted reference compounds were prepared by three methods of CuAAC chemistry. In line with the limited success or complete failure of attempted conversions with low catalyst loadings, by means of DFT modeling studies, we demonstrated that a substantial part of the Cu(I) ions can be chelated and thus trapped in the aroylamino-substituted cinchona fragment and all of the accessible coordinating sites of the chalcone residues. Accordingly, increased amounts of catalysts were used to achieve acceptable yields; however, the cycloadditions with para-azidochalcones were accompanied by partial or complete aldehyde-forming hydrolytic fission of the enone C=C bond in a substituent-, solvent- and copper load-dependent manner. The experienced hydrolytic stability of the hybrids obtained by cycloadditions with ortho-azidochalcones was interpreted in terms of relative energetics, DFT reactivity indices and MO analysis of simplified models of two isomer copper-enone complexes. The novel hybrids were evaluated on HeLa, MDA-MB-231 and A2780 cell lines and showed substantial activity at low-to-submicromolar concentrations. An organometallic model carrying 3,4,5-trimethoxyphenyl residue in the enone part with a para-disubstituted benzene ring in the central skeletal region was identified as the most potent antiproliferative lead, characterized by submicromolar IC50 values measured on the three investigated cells. The biological assays also disclosed that this ferrocenoylamino-containing lead compound displays a ca. two- to five-fold more substantial antiproliferative effect than its benzoylamino-substituted counterpart.

Chalcone derivatives' interaction with human serum albumin and cyclooxygenase-2

Chalcone derivatives are an extremely valuable class of compounds, primarily due to the keto-ethylenic group, CO-CH[double bond, length as m-dash]CH-, they contain. Moreover, the presence of a reactive α,β-unsaturated carbonyl group confers upon them a broad range of pharmacological properties. Recent developments in heterocyclic chemistry have led to the synthesis of chalcone derivatives, which have been biologically investigated for their activity against certain diseases. In this study, we investigated the binding of new chalcone derivatives with COX-2 (cyclooxygenase-2) and HSA (Human Serum Albumin) using spectroscopic and molecular modeling studies. COX-2 is commonly found in cancer and plays a role in the production of prostaglandin E (2), which can help tumors grow by binding to receptors. HSA is the most abundant protein in blood plasma, and it transports various compounds, including hormones and fatty acids. The conformation of chalcone derivatives in the HSA complex system was established through fluorescence steady and excited state spectroscopy techniques and FTIR analyses. To gain a more comprehensive understanding, molecular docking, and dynamics were conducted on the target protein (COX-2) and transport protein (HSA). In addition, we conducted density-functional theory (DFT) and single-point DFT to understand intermolecular interaction in protein active sites.

Flexibility in the bridge of chalcone derivatives is important for the inhibition of cellular growth

Chalcones and their derivatives are a privileged scaffold in medicinal chemistry, demonstrating numerous biological activities. These molecules have shown significant potential toward the development of novel cancer therapies. While much is known about modification to the chalcone aryl rings, little is known about conformations of the bridge between the aryl rings. Here we report the synthesis and biological evaluation of a series of molecules with flexible and rigid bridge conformations. Crystal structures of a select group of molecules were determined. Flexibility in the chalcone bridge containing the enone moiety was determined to be important for activity. Screening in three distinct cancer cell lines showed significant differences in the activity between the flexible and rigid conformations. Crystal structures suggest an increase in bond rotation and weakened π-bonding in the flexible chalcone bridge, which may contribute to the stronger anti-proliferative activity.

Hydroxy Chalcones and Analogs with Chemopreventive Properties

The aim of this review is to highlight the chemopreventive properties of hydroxy-substituted natural and synthetic chalcones along with a number of their analogs. These products display various biological activities, and have many applications against various diseases. Antioxidant and anti-inflammatory properties of chalcones bearing hydroxy substituents are underlined. The influence of hydroxy substituents located on ring A, B, or both are systematized according to the exhibited biological properties.

Novel Erlotinib-Chalcone Hybrids Diminish Resistance in Head and Neck Cancer by Inducing Multiple Cell Death Mechanisms

In a search for novel therapeutic options for head and neck squamous cell carcinomas (HNSCCs) generally treated with limited therapeutic success, we synthesized a series of novel erlotinib-chalcone molecular hybrids with 1,2,3-triazole and alkyne linkers and evaluated them for their anticancer activity on Fadu, Detroit 562 and SCC-25 HNSCC cell lines. Time- and dose-dependent cell viability measurements disclosed a significantly increased efficiency of the hybrids compared to the 1:1 combination of erlotinib and a reference chalcone. The clonogenic assay demonstrated that hybrids eradicate HNSCC cells in low micromolar concentrations. Experiments focusing on potential molecular targets indicate that the hybrids trigger the anticancer effect by a complementary mechanism of action that is independent of the canonical targets of their molecular fragments. Confocal microscopic imaging and real-time apoptosis/necrosis detection assay pointed to slightly different cell death mechanisms induced by the most prominent triazole- and alkyne-tethered hybrids (6a and 13, respectively). While 6a featured the lowest IC₅₀ values on each of the three HNSCC cell lines, in Detroit 562 cells, this hybrid induced necrosis more markedly compared to 13. The therapeutic potential indicated by the observed anticancer efficacy of our selected hybrid molecules validates the concept of development and justifies further investigation to reveal the underlying mechanism of action.

Chalcones: Promising therapeutic agents targeting key players and signaling pathways regulating the hallmarks of cancer

The need for innovative anticancer treatments with high effectiveness and low toxicity is urgent due to the development of malignancies that are resistant to chemotherapeutic agents and the poor specificity of existing anticancer treatments. Chalcones are 1,3-diaryl-2-propen-1-ones, which are the precursors for flavonoids and isoflavonoids. Chalcones are readily available from a wide range of natural resources and consist of very basic chemical scaffolds. Because the ease with which the synthesis it allows for the production of several chalcone derivatives. Various in-vitro and in-vivo studies indicate that naturally occurring and synthetic chalcone derivatives exhibit promising biological activities against cancer hallmarks such as proliferation, angiogenesis, invasion, metastasis, inflammation, stemness, and regulation of cancer epigenetics. According to their structure and functional groups, chalcones derivatives and their hybrid compounds exert a broad range of biological activities through targeting key elements and signaling molecules relevant to cancer progression. This review will provide valuable insights into the latest updates of chalcone groups as anticancer agents and extensively discuss their underlying molecular mechanisms of action.

Recruitment of chalcone's potential in drug discovery of anti-SARS-CoV-2 agents

Chalcone is an interesting scaffold found in the structure of many naturally occurring molecules. Medicinal chemists are commonly interested in designing new chalcone-based structures because of having the α, β-unsaturated ketone functional group, which allows these compounds to participate in Michael's reaction and create strong covalent bonds at the active sites of the targets. Some studies have identified several natural chalcone-based compounds with the ability to inhibit the severe acute respiratory syndrome coronavirus and Middle East respiratory syndrome coronavirus proteases. A few years after the advent of the coronavirus disease 2019 pandemic and the publication of many findings in this regard, there is some evidence that suggests chalcone scaffolding has great potential for use in the design and development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inhibitors. Artificial placement of this scaffold in the structure of optimized anti-SARS-CoV-2 compounds can potentially provide irreversible inhibition of the viral cysteine proteases 3-chymotrypsin-like protease and papain-like protease by creating Michael interaction. Despite having remarkable capabilities, the use of chalcone scaffold in drug design and discovery of SARS-CoV-2 inhibitors seems to have been largely neglected. This review addresses issues that could lead to further consideration of chalcone scaffolding in the structure of SARS-CoV-2 protease inhibitors in the future.

A novel synthetic chalcone derivative, 2,4,6-trimethoxy-4'-nitrochalcone (Ch-19), exerted anti-tumor effects through stimulating ROS accumulation and inducing apoptosis in esophageal cancer cells

Esophageal cancer has always been associated with poor prognosis and a low five-year survival rate. Chalcone, a flavonoid family member, has shown anti-tumor property in several types of cancer. However, few studies reported the potency and mechanisms of action of synthetic Chalcone derivatives against esophageal squamous cell carcinoma. In this study, we designed and synthesized a series of novel chalcone analogs and Ch-19 was selected for its superior anti-tumor potency. Results indicated that Ch-19 shows a dose- and time-dependent anti-tumor activity in both KYSE-450 and Eca-109 esophageal cancer cells. Moreover, treatment of Ch-19 resulted in the regression of KYSE-450 tumor xenografts in nude mice. Furthermore, we investigated the potential mechanism involved in the effective anti-tumor effects of Ch-19. As a result, we observed that Ch-19 treatment promoted ROS accumulation and caused G2/M phase arrest in both Eca-109 and KYSE-450 cancer cell lines, thereby resulting in cell apoptosis. Taken together, our study provided a novel synthetic chalcone derivative as a potential anti-tumor therapeutic candidate for treating esophageal cancer.

Synthesis and Anticancer Activities of Novel Bis-chalcones Incorporating the 1,3-diphenyl-1H-pyrazole Moiety: In Silico and In Vitro Studies

Abstract:

A new series of bis-chalcones 5-10 has been prepared by the condensation reaction of one equivalent of bis(acetophenones) 3a-f with two equivalents of 1,3-diphenyl-1H-pyrazole-4-carbaldehyde 4. The newly prepared compounds 5-10 have been fully characterized and evaluated as in vitro anticancer agents against a panel of human cancer cell lines A431, A549, PC3, and a normal human skin fibroblast BJ1.

Aims:

The current work is designed to explore the anti-cancer activity of novel bis-chalcones incorporating a 1,3-diphenyl-1H-pyrazole moiety.

Background:

Chalcones represent one of the most important organic compounds that have been attracting the interest of many researchers in drug discovery.

Objective:

The present study was carried out to explore anti-cancer activity of novel bis-chalcones incorporating a 1,3-diphenyl-1H-pyrazole moiety as in vitro and in silico studies.

Materials and Methods:

We used the condensation reaction to prepare bis-chalcones incorporating 1,3- diphenyl-1H-pyrazole moiety. The MTT Assay, Anti-cancer activity, Gene expression, DNA Fragmentation, DNA Damage, and Molecular docking were investigated.

Results:

Compounds 5 and 9 were found to be the most promising compounds in the prepared series with IC50 (50.3 and 50.1 μg/ml, respectively) against epidermoid cancer cell line A431 compared to doxorubicin as a reference drug.

Conclusion:

All of these results showed that chalcones 5 and 9 have promising anti-cancer properties without cytotoxic effect, which could make them a promising active component for further studies.

[1,2,4] Triazolo [3,4-a]isoquinoline chalcone derivative exhibits anticancer activity via induction of oxidative stress, DNA damage, and apoptosis in Ehrlich solid carcinoma-bearing mice

Despite the advances made in cancer therapeutics, their adverse effects remain a major concern, putting safer therapeutic options in high demand. Since chalcones, a group of flavonoids and isoflavonoids, act as promising anticancer agents, we aimed to evaluate the in vivo anticancer activity of a synthetic isoquinoline chalcone (CHE) in a mice model with Ehrlich solid carcinoma. Our in vivo pilot experiments revealed that the maximum tolerated body weight-adjusted CHE dose was 428 mg/kg. Female BALB/c mice were inoculated with Ehrlich ascites carcinoma cells and randomly assigned to three different CHE doses administered intraperitoneally (IP; 107, 214, and 321 mg/kg) twice a week for two consecutive weeks. A group injected with doxorubicin (DOX; 4 mg/kg IP) was used as a positive control. We found that in CHE-treated groups: (1) tumor weight was significantly decreased; (2) the total antioxidant concentration was substantially depleted in tumor tissues, resulting in elevated oxidative stress and DNA damage evidenced through DNA fragmentation and comet assays; (3) pro-apoptotic genes p53 and Bax, assessed via qPCR, were significantly upregulated. Interestingly, CHE treatment reduced immunohistochemical staining of the proliferative marker ki67, whereas BAX was increased. Notably, histopathological examination indicated that unlike DOX, CHE treatment had minimal toxicity on the liver and kidney. In conclusion, CHE exerts antitumor activity via induction of oxidative stress and DNA damage that lead to apoptosis, making CHE a promising candidate for solid tumor therapy.

The synthesis of novel thioderivative chalcones and their influence on NF-κB, STAT3 and NRF2 signaling pathways in colorectal cancer cells

This study aimed to synthesize new thioderivative chalcones and analyze their impact on the NF-κB, STAT3, EGFR and Nrf2 signaling pathways in colorectal cancer cells. Among the studied compounds, derivatives 4 and 5 decreased the activation of NF-κB and the expression of the target gene COX-2. In the case of STAT3, we observed the inhibition of activation of this signaling pathway after influencing derivative 4. Increased activation of the Nrf2 signaling pathway was demonstrated for derivatives 5 and 7 in DLD-1 and HCT116 cells. The results of this study indicated that new chalcone derivatives, especially compounds 4, 5, and-to some degree-7, possess potential applications in the prevention of colorectal cancer.

Novel dual inhibitor for targeting PIM1 and FGFR1 kinases inhibits colorectal cancer growth in vitro and patient-derived xenografts in vivo

Colorectal cancer (CRC) is the second most common cause of cancer-related death in the world. The pro-viral integration site for Moloney murine leukemia virus 1 (PIM1) is a proto-oncogene and belongs to the serine/threonine kinase family, which are involved in cell proliferation, migration, and apoptosis. Fibroblast growth factor receptor 1 (FGFR1) is a tyrosine kinase that has been implicated in cell proliferation, differentiation and migration. Small molecule HCI-48 is a derivative of chalcone, a class of compounds known to possess anti-tumor, anti-inflammatory and antibacterial effects. However, the underlying mechanism of chalcones against colorectal cancer remains unclear. This study reports that HCI-48 mainly targets PIM1 and FGFR1 kinases, thereby eliciting antitumor effects on colorectal cancer growth in vitro and in vivo. HCI-48 inhibited the activity of both PIM1 and FGFR1 kinases in an ATP-dependent manner, as revealed by computational docking models. Cell-based assays showed that HCI-48 inhibited cell proliferation in CRC cells (HCT-15, DLD1, HCT-116 and SW620), and induced cell cycle arrest in the G2/M phase through modulation of cyclin A2. HCI-48 also induced cellular apoptosis, as evidenced by an increase in the expression of apoptosis biomarkers such as cleaved PARP, cleaved caspase 3 and cleaved caspase 7. Moreover, HCI-48 attenuated the activation of downstream components of the PIM1 and FGFR1 signaling pathways. Using patient-derived xenograft (PDX) murine tumor models, we found that treatment with HCI-48 diminished the PDX tumor growth of implanted CRC tissue expressing high protein levels of PIM1 and FGFR1. This study suggests that the inhibitory effect of HCI-48 on colorectal tumor growth is mainly mediated through the dual-targeting of PIM1 and FGFR1 kinases. This work provides a theoretical basis for the future application of HCI-48 in the treatment of clinical CRC.

Orchestrating a β-Hydride Elimination Pathway in Palladium(II)-Catalyzed Arylation/Alkenylation of Cyclopropanols Using Organoboron Reagents

The scope of chemoselective β-hydride elimination in the context of arylation/alkenylation of homoenolates from cyclopropanol precursors using organoboronic reagents as transmetalation coupling partners was examined. The reaction optimization paradigm revealed a simple ligand-free Pd(II) catalytic system to be most efficient under open air conditions. The preparative scope, which was investigated with 48 examples, supported the applicability of this reaction to a wide range of substrates tolerating a variety of functional groups while delivering β-substituted enone and dienone derivatives in 62-95% yields.

Chalcones against the hallmarks of cancer: a mini-review

Chalcones (1,3-diphenylpropen-1-ones) are a class of flavonoids that have been shown a broad spectrum of biological activities with therapeutic potential. Naturally occurring chalcones or synthetic chalcone derivatives have been extensively investigated as anticancer compounds. Cancer is still among the leading causes of death globally, although cancer treatments have improved over the past decades. Most of chemotherapeutic drugs target proliferating tumor cells; however, the cancer cells capabilities are also associated to tumor surround microenvironment. Thereby, the search of new compounds with a broad antitumor activity is still a great challenge. The cytotoxicity mechanisms of chalcones are beyond apoptosis induction in tumor cells, which make them promising compound for cancer therapy. In this mini-review we summarized recent studies that describe the anticancer potential of chalcones related to some of hallmarks of cancer. We shed a light on sustaining proliferative signaling, tumor-promoting inflammation, activating invasion and metastasis, inducing angiogenesis and resisting cell death.

Chalcones identify cTXNPx as a potential antileishmanial drug target

With current drug treatments failing due to toxicity, low efficacy and resistance; leishmaniasis is a major global health challenge that desperately needs new validated drug targets. Inspired by activity of the natural chalcone 2’,6’-dihydroxy-4’-methoxychalcone (DMC), the nitro-analogue, 3-nitro-2’,4’,6’- trimethoxychalcone (NAT22, 1c) was identified as potent broad spectrum antileishmanial drug lead. Structural modification provided an alkyne containing chemical probe that labelled a protein within the parasite that was confirmed as cytosolic tryparedoxin peroxidase (cTXNPx). Crucially, labelling is observed in both promastigote and intramacrophage amastigote life forms, with no evidence of host macrophage toxicity. Incubation of the chalcone in the parasite leads to ROS accumulation and parasite death. Deletion of cTXNPx, by CRISPR-Cas9, dramatically impacts upon the parasite phenotype and reduces the antileishmanial activity of the chalcone analogue. Molecular docking studies with a homology model of in-silico cTXNPx suggest that the chalcone is able to bind in the putative active site hindering access to the crucial cysteine residue. Collectively, this work identifies cTXNPx as an important target for antileishmanial chalcones.

Leishmaniasis is an insect vector-borne parasitic disease. With >350 million people world wide considered at risk, 12 million people currently infected and an economic cost that can be estimated in terms of >3.3 million working life years lost, leishmaniasis is a major global health challenge. The disease is of particular importance in Brazil. Current treatment of leishmaniasis is difficult requiring a long, costly course of drug treatment using old drugs with poor safety indications requiring close medical supervision. Moreover, resistance to current antileishmanials is growing, emphasising a major need for new drug targets. In earlier work we had identified a naturally inspired chalcone which had promising antileishmanial activity but with no known mode of action. In this work we use an analogue of this molecule as an activity based probe to identify a protein target of the chalcone. This protein, cTXNPx, has a major role in protecting the parasite against attack by reactive oxygen species in the host cell. By inhibiting this protein the parasite can no longer survive in the host. Collectively this work validates cTXNPx as a drug target with the chalcone as a lead structure for future drug discovery programmes.

Design, Synthesis, and Anticancer Activity Studies of Novel Quinoline-Chalcone Derivatives

The chalcone and quinoline scaffolds are frequently utilized to design novel anticancer agents. As the continuation of our work on effective anticancer agents, we assumed that linking chalcone fragment to the quinoline scaffold through the principle of molecular hybridization strategy could produce novel compounds with potential anticancer activity. Therefore, quinoline-chalcone derivatives were designed and synthesized, and we explored their antiproliferative activity against MGC-803, HCT-116, and MCF-7 cells. Among these compounds, compound 12e exhibited a most excellent inhibitory potency against MGC-803, HCT-116, and MCF-7 cells with IC50 values of 1.38, 5.34, and 5.21 µM, respectively. The structure-activity relationship of quinoline-chalcone derivatives was preliminarily explored in this report. Further mechanism studies suggested that compound 12e inhibited MGC-803 cells in a dose-dependent manner and the cell colony formation activity of MGC-803 cells, arrested MGC-803 cells at the G2/M phase and significantly upregulated the levels of apoptosis-related proteins (Caspase3/9 and cleaved-PARP) in MGC-803 cells. In addition, compound 12e could significantly induce ROS generation, and was dependent on ROS production to exert inhibitory effects on gastric cancer cells. Taken together, all the results suggested that directly linking chalcone fragment to the quinoline scaffold could produce novel anticancer molecules, and compound 12e might be a valuable lead compound for the development of anticancer agents.

Design and synthesis of methoxyphenyl- and coumarin-based chalcone derivatives as anti-inflammatory agents by inhibition of NO production and down-regulation of NF-κB in LPS-induced RAW264.7 macrophage cells

Exaggerated inflammatory responses may cause serious and debilitating diseases such as acute lung injury and rheumatoid arthritis. Two series of chalcone derivatives were prepared as anti-inflammatory agents. Methoxylated phenyl-based chalcones 2a-l and coumarin-based chalcones 3a-f were synthesized and compared for their inhibition of COX-2 enzyme and nitric oxide production suppression. Methoxylated phenyl-based chalcones showed better inhibition to COX-2 enzyme and nitric oxide suppression than the coumarin-based chalcones. Among the 18 synthesized chalcone derivatives, compound 2f exhibited the highest anti-inflammatory activity by inhibition of nitric oxide concentration in LPS-induced RAW264.7 macrophages (IC₅₀ = 11.2 μM). The tested compound 2f showed suppression of iNOS and COX-2 enzymes. Moreover, compound 2f decreases in the expression of NF-κB and phosphorylated IκB in LPS-stimulated macrophages. Finally, docking studies suggested the inhibition of IKKβ as a mechanism of action and highlighted the importance of 2f hydrophobic interactions.

A comparative theoretical mechanism on simplified flavonoid derivatives and isoxazolone analogous as Michael system inhibitor

Flavonoids are a big class of natural product and have a wide range of biological activities. Some of these applications depend on its antioxidant capacity. Nevertheless, another mechanism can be involved by means of alkylation reaction on α,β-unsaturated carbonyl system. This study aimed to evaluate the antioxidant capacity and the chemical reactivity among simplified flavonoid derivatives and isoxazolone analogous as Michael system by using B3LYP functional and 6-311 g(d,p) basis set. Frontier molecular orbital, ionization potential (IP), spin density contributions, and Fukui index explain the antioxidant capacity and reactivity index on isoxazolone and its related derivatives. The best contribution at β-alkene moiety is related to better reactivity of α,β-unsaturated carbonyl group. A decrease in antioxidant capacity is related to an increase in the chemical reactivity index. The frontier molecular orbitals show that aurone is more reactive than isoxazolone. In accordance with Fukui index, isoxazolone can be better inhibitor as Michael system when compared to flavonoid derivatives. Graphical abstract.

Molecular targets and anticancer activity of quinoline-chalcone hybrids: literature review

α,β-Unsaturated chalcone moieties and quinoline scaffolds play an important role in medicinal chemistry, especially in the identification and development of potential anticancer agents. The multi-target approach or hybridization is considered as a promising strategy in drug design and discovery. Hybridization may improve the affinity and potency while simultaneously decreasing the resistance and/or side effects. The conjugation of quinolines with chalcones has been a promising approach to the identification of potential anticancer agents. Most of these hybrids showed anticancer activities through the inhibition of tubulin polymerization, different kinases, topoisomerases, or by affecting DNA cleavage activity. Accordingly, this class of compounds can be classified based on their molecular modes of action. In this article, the quinolone-chalcone hybrids with potential anticancer activity have been reviewed. This class of compounds might be helpful for the design, discovery and development of new and potential multi-target anticancer agents or drugs.

Evaluation of nitrocatechol chalcone and pyrazoline derivatives as inhibitors of catechol-O-methyltransferase and monoamine oxidase

Literature reports that chalcones inhibit the monoamine oxidase (MAO) enzymes, mostly with specificity for the MAO-B isoform, while nitrocatechol compounds are established inhibitors of catechol-O-methyltransferase (COMT). Based on this, nitrocatechol derivatives of chalcone have been proposed to represent dual-target-directed compounds that may inhibit both MAO-B and COMT. Both these enzymes play key roles in the metabolism of dopamine and levodopa, and inhibitors are thus relevant to the treatment of Parkinson's disease. The present study expands on the discovery of dual MAO-B/COMT inhibitors by synthesising additional nitrocatechol derivatives of chalcones which include heterocyclic derivatives, and converting them to the corresponding pyrazoline derivatives. The newly synthesised chalcone and pyrazoline compounds were evaluated as inhibitors of human MAO and rat COMT, and the inhibition potencies were expressed as IC₅₀ values. A pyrazoline derivative, compound 8b, was the most potent COMT inhibitor with an IC₅₀ value of 0.048 μM. This is more potent than the reference COMT inhibitor, entacapone, which has an IC₅₀ value of 0.23 μM. The results indicated that the pyrazoline derivatives (IC₅₀ = 0.048-0.21 µM) are more potent COMT inhibitors than the chalcones (IC₅₀ = 0.14-0.29 µM). Unfortunately, the chalcone and pyrazoline derivatives were weak MAO inhibitors with IC₅₀ values > 41.4 µM. This study concludes that the nitrocatechol derivatives investigated here are promising COMT inhibitors, while not being suitable as MAO inhibitors. Using molecular docking, potential binding modes and interactions of selected inhibitors with COMT are proposed.

Development of a novel nitric oxide (NO) production inhibitor with potential therapeutic effect on chronic inflammation

Inflammation is a complex biological response to stimuli. Activated macrophages induced excessively release of pro-inflammatory cytokines and mediators such as endogenous radical nitric oxide (NO) play a significant role in the progression of multiple inflammatory diseases. Both natural and synthetic chalcones possess a wide range of bioactivities. In this work, thirty-nine chalcones and three related compounds, including several novel ones, based on bioactive kava chalcones were designed, synthesized and their inhibitory effects on NO production in RAW 264.7 cells were evaluated. The novel compound (E)-1-(2'-hydroxy-4',6'-dimethoxyphenyl)-3-(3-methoxy-4-(3-morpholinopropoxy)phenyl)prop-2-en-1-one (53) exhibited a better inhibitory activity (84.0%) on NO production at 10 μM (IC₅₀ = 6.4 μM) with the lowest cytotoxicity (IC₅₀ > 80 μM) among the tested compounds. Besides, western blot analysis indicated that compound 53 was a potent down-regulator of inducible nitric oxide synthase (iNOS) protein. Docking study revealed that compound 53 also can dock into the active site of iNOS. Furthermore, at the dose of 10 mg/kg/day, compound 53 could both significantly suppress the progression of inflammation on collagen-induced arthritis (CIA) and adjuvant-induced arthritis (AIA) models. In addition, the structure-activity relationship (SAR) of the kava chalcones based analogs was also depicted.

Structural, Hirshfeld and DFT studies of conjugated D-π-A carbazole chalcone crystal

A new conjugated carbazole chalcone compound, (E)-3-[4-(9,9a-di-hydro-8aH-carbazol-9-yl)phen-yl]-1-(4-nitro-phen-yl)prop-2-en-1-one (CPNC), C27H18N2O3, was synthesized using a Claisen-Schmidt condensation reaction. CPNC crystallizes in the monoclinic non-centrosymmetric space group Cc and adopts an s-cis conformation with respect to the ethyl-enic double bonds (C=O and C=C). The crystal packing features C-H⋯O and C-H⋯π inter-actions whose percentage contribution was qu-anti-fied by Hirshfeld surface analysis. Quantum chemistry calculations including geometrical optimization and mol-ecular electrostatic potential (MEP) were analysed by density functional theory (DFT) with a B3LYP/6-311 G++(d,p) basis set.

Privileged Scaffold Chalcone: Synthesis, Characterization and Its Mechanistic Interaction Studies with BSA Employing Spectroscopic and Chemoinformatics Approaches

Chalcone, a privileged structure, is considered as an effective template in the field of medicinal chemistry for potent drug discovery. In the present study, a privileged template chalcone was designed, synthesized, and characterized by various spectroscopic techniques (NMR, high-resolution mass spectrometry, Fourier transform infrared (FT-IR) spectroscopy, UV spectroscopy, and single-crystal X-ray diffraction). The mechanism of binding of chalcone with bovine serum albumin (BSA) was determined by multispectroscopic techniques and computational methods. Steady-state fluorescence spectroscopy suggests that the intrinsic fluorescence of BSA was quenched upon the addition of chalcone by the combined dynamic and static quenching mechanism. Time-resolved spectroscopy confirms complex formation. FT-IR and circular dichroism spectroscopy suggested the presence of chalcone in the BSA molecule microenvironment and also the possibility of rearrangement of the native structure of BSA. Moreover, molecular docking studies confirm the moderate binding of chalcone with BSA and the molecular dynamics simulation analysis shows the stability of the BSA-drug complex system with minimal deformability fluctuations and potential interaction by the covariance matrix. Moreover, pharmacodynamics and pharmacological analysis show good results through Lipinski rules, with no toxicity profile and high gastrointestinal absorptions by boiled egg permeation assays. This study elucidates the mechanistic profile of the privileged chalcone scaffold to be used in therapeutic applications.

Advances in covalent kinase inhibitors

This comprehensive review details recent advances, challenges and innovations in covalent kinase inhibition within a 10 year period (2007–2018).

Synthesis, Structure and In Vitro Cytotoxic Activity of Novel Cinchona-Chalcone Hybrids with 1,4-Disubstituted- and 1,5-Disubstituted 1,2,3-Triazole Linkers

By means of copper(I)-and ruthenium(II)-catalyzed click reactions of quinine- and quinidine-derived alkynes with azide-substituted chalcones a systematic series of novel cinchona-chalcone hybrid compounds, containing 1,4-disubstituted- and 1,5-disubstituted 1,2,3-triazole linkers, were synthesized and evaluated for their cytotoxic activity on four human malignant cell lines (PANC-1, COLO-205, A2058 and EBC-1). In most cases, the cyclization reactions were accompanied by the transition-metal-catalyzed epimerization of the C9-stereogenic centre in the cinchona fragment. The results of the in vitro assays disclosed that all the prepared hybrids exhibit marked cytotoxicity in concentrations of low micromolar range, while the C9-epimerized model comprising quinidine- and (E)-1-(4-(3-oxo-3-(3,4,5-trimethoxyphenyl)prop-1-en-1-yl)phenyl) fragments, connected by 1,5-disubstituted 1,2,3-triazole linker, and can be regarded as the most potent lead of which activity is probably associated with a limited conformational space allowing for the adoption of a relatively rigid well-defined conformation identified by DFT modelling. The mechanism of action of this hybrid along with that of a model with markedly decreased activity were approached by comparative cell-cycle analyses in PANC-1 cells. These studies disclosed that the hybrid of enhanced antiproliferative activity exerts significantly more extensive inhibitory effects in subG1, S and G2/M phases than does the less cytotoxic counterpart.

Anti-inflammatory effect of synthesized indole-based chalcone (2E)-3-(4-bromophenyl)-1-(1H-indol-3-yl) prop-2-en-1-one: an in vitro and in vivo studies

Purpose: Chalcones are precursors of flavonoids with a wide range of pharmacological activities. This study evaluates the anti-inflammatory effect of indole based chalcone derivative (2E)-3-(4-bromophenyl)-1-(1H-indol-3-yl) prop-2-en-1-one (IC9) on lipopolysaccharide (LPS) activated murine macrophages RAW264.7 cells and carrageenan-induced acute model in rats.Materials and methods: LPS-treated RAW264.7 cell lines and carrageenan-induced animal model were employed to evaluate the anti-inflammatory activity of IC9. The cell cytotoxicity studies were carried out by MTT assay. Reactive oxygen species (ROS) production and other inflammatory markers such as prostaglandin E2 (PGE2), nitric oxide (NO) as well as cyclooxygenase-2 (COX-2) activity were determined using ELISA. The RT-PCR was performed to determine mRNA expressions in the case of inducible nitric oxide synthase (iNOS), COX-2, Toll-like receptor-4 (TLR-4) and also nuclear translocation of NF-κB activity.Results: LPS-activated RAW264.7 cells showed an increased level of ROS generation and other inflammatory markers such as PGE2, NO level and COX-2 activity. Expression of iNOS, COX- 2 and TLR-4 mRNA expression were also up-regulated along with nuclear translocation of NF-κB. On IC9 supplementation, all the above parameters of LPS-activated cells were found to be reversed, resembling the control group. Moreover, IC9 significantly inhibited paw swelling and exhibited maximum inhibition of 78.45% at low dose of 7.5 mg/kg.bwt.Conclusions: The targeting anti-inflammatory efficacy and profound NF-κB sensitive transcriptional regulatory mechanism of IC9 accounts for its effective anti-inflammatory action.

Synthesis and biological evaluation of structurally diverse α-conformationally restricted chalcones and related analogues

Numerous members of the combretastatin and chalcone families of natural products function as inhibitors of tubulin polymerization through a binding interaction at the colchicine site on β-tubulin. These molecular scaffolds inspired the development of many structurally modified derivatives and analogues as promising anticancer agents. A productive design blueprint that involved molecular hybridization of the pharmacophore moieties of combretastatin A-4 (CA4) and the chalcones led to the discovery of two promising lead molecules referred to as KGP413 and SD400. The corresponding water-soluble phosphate prodrug salts of KGP413 and SD400 selectively damaged tumor-associated vasculature, thus highlighting the potential development of these molecules as vascular disrupting agents (VDAs). These previous studies prompted our current investigation of conformationally restricted chalcones. Herein, we report the synthesis of cyclic chalcones and related analogues that incorporate structural motifs of CA4, and evaluation of their cytotoxicity against human cancer cell lines [NCI-H460 (lung), DU-145 (prostate), and SK-OV-3 (ovarian)]. While these molecules proved inactive as inhibitors of tubulin polymerization (IC50 > 20 μM), eight molecules demonstrated good antiproliferative activity (GI50 < 20 μM) against all three cancer cell lines, and compounds 2j and 2l demonstrated sub-micromolar cytotoxicity. To the best of our knowledge these molecules represent the most potent (based on GI50) cyclic chalcones known to date, and are promising lead molecules for continued investigation.

Chalcone Derivative L6H21 Reduces EtOH + LPS-Induced Liver Injury Through Inhibition of NLRP3 Inflammasome Activation

BACKGROUND

Chronic alcohol intake increases circulating endotoxin levels causing excessive inflammation that aggravates the liver injury. (E)-2,3-dimethoxy-4'-methoxychalcone (L6H21), a derivative of chalcone, has been found to inhibit inflammation in cardiac diseases and nonalcoholic fatty liver disease. However, the use of L6H21 in alcoholic liver disease to inhibit exotoxin-associated inflammation has not been explored. In this study, we examined the effects of L6H21 on EtOH + LPS-induced hepatic inflammation, steatosis, and liver injury and investigated the underlying mechanisms.

METHODS

C57BL6 mice were treated with 5% EtOH for 10 days, and LPS was given to the mice 6 hours before sacrificing. One group of mice was supplemented with L6H21 with EtOH and LPS. RAW264.7 cells were used to analyze the effects of L6H21 on macrophage activation.

RESULTS

EtOH + LPS treatment significantly increased hepatic steatosis and serum levels of alanine transaminase (ALT) and aspartate transaminase (AST), which were reduced by L6H21 treatment. EtOH + LPS treatment increased hepatic inflammation, as shown by the increased hepatic protein levels of Toll-like receptor-4, p65, and p-IκB, and increased oxidative stress, as shown by protein carbonyl levels and reactive oxygen species formation, which were reduced by L6H21 treatment. In addition, L6H21 treatment markedly inhibited EtOH + LPS-elevated hepatic protein levels of NLRP3, cleaved caspase-1, cleaved IL-1β, and caspase-1-associated apoptosis.

CONCLUSIONS

Our results demonstrate that L6H21 treatment inhibits EtOH + LPS-induced liver steatosis and injury through suppression of NLRP3 inflammasome activation. L6H21 may be used as an alternative strategy for ALD prevention/treatment.

Promising anti-inflammatory effects of chalcones via inhibition of cyclooxygenase, prostaglandin E2, inducible NO synthase and nuclear factor κb activities

Chalcones (1, 3-Diphenyl-2-propen-1-one) consist of a three carbon α, β-unsaturated carbonyl system and act as precursors for the biosynthesis of flavonoids in plants. However, laboratory synthesis of various chalcones has also been reported. Both natural and synthetic chalcones are known to exhibit a variety of pharmacological activities such as anti-inflammatory, antitumor, antibacterial, antifungal, antimalarial and antituberculosis. These promising activities, ease of synthesis and simple chemical structure have awarded chalcones considerable attraction. This review focuses on the anti-inflammatory effects of chalcones, caused by their inhibitory action primarily against the activities and expressions of four key inflammatory mediators viz., cyclooxygenase, prostaglandin E₂, inducible NO synthase, and nuclear factor κB. Various methodologies for the synthesis of chalcones have been discussed. The potency of recently synthesized chalcones is given in terms of their IC₅₀ values. Structure-Activity Relationships (SARs) of a variety of chalcone derivatives have been discussed. Computational methods were applied to calculate the ideal orientation of a typical chalcone scaffold against three enzymes, namely, cyclooxygenase-1, cyclooxygenase-2 and inducible NO synthase for the formation of stable complexes. The global market of anti-inflammatory drugs and its expected growth (from 2018 to 2026) have been discussed. SAR analysis, docking studies, and future prospects all together provide useful clues for the synthesis of novel chalcones of improved anti-inflammatory activities.

Design, synthesis and biological evaluation of chalcone analogues with novel dual antioxidant mechanisms as potential anti-ischemic stroke agents

Scavenging reactive oxygen species (ROS) by antioxidants is the important therapy to cerebral ischemia-reperfusion injury (CIRI) in stroke. The antioxidant with novel dual-antioxidant mechanism of directly scavenging ROS and indirectly through antioxidant pathway activation may be a promising CIRI therapeutic strategy. In our study, a series of chalcone analogues were designed and synthesized, and multiple potential chalcone analogues with dual antioxidant mechanisms were screened. Among these compounds, the most active 33 not only conferred cytoprotection of H2O2-induced oxidative damage in PC12 cells through scavenging free radicals directly and activating NRF2/ARE antioxidant pathway at the same time, but also played an important role against ischemia/reperfusion-related brain injury in animals. More importantly, in comparison with mono-antioxidant mechanism compounds, 33 exhibited higher cytoprotective and neuroprotective potential in vitro and in vivo. Overall, our findings showed compound 33 could emerge as a promising anti-ischemic stroke drug candidate and provided novel dual-antioxidant mechanism strategies and concepts for oxidative stress-related diseases treatment.