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Plant-derived and semi-synthetic calanolide compounds with in vitro activity against both human immunodeficiency virus type 1 and human cytomegalovirus

Xu ZQ, Kern ER, Westbrook L, Allen LB, Buckheit RW, Tseng CK, et al.

Antivir Chem Chemother, 2000 Jan;11(1):23-9.
PMID: 10693651

Plant-derived and semi-synthetic calanolide compounds with anti-human immunodeficiency virus type 1 (HIV-1) activity were tested for anti-human cytomegalovirus (HCMV) activity in both cytopathic effect inhibition and plaque reduction assays. The results indicated that the anti-HCMV activity of calanolide compounds does not correlate with their activity against HIV-1. The semi-synthetic 12-keto derivatives tended to be more active against HCMV than the corresponding 12-OH congeners, which were more active against HIV-1. It appeared that the 7,8-unsaturated double bond in the chromene ring played a certain role in maintaining activities against both HCMV and HIV-1. Saturation of the double bond increased the EC50 values against both viruses, with concomitant increase in toxicity. The calanolide compounds reported here are the first non-nucleoside analogues capable of inhibiting both HIV-1 and HCMV and, therefore, may be useful chemoprophylactic agents for HCMV in HIV-infected people or vice versa.

Matched MeSH terms: Coumarins/pharmacology*
A new coumarin from Calophyllum hosei

Daud SB, Ee GC, Malek EA, Teh SS, See I

Nat Prod Res, 2014;28(19):1534-8.
PMID: 24897077 DOI: 10.1080/14786419.2014.924001

A new coumarin, hoseimarin (1), together with four other xanthones, trapezifolizanthone (2), osajaxanthone (3), β-mangostin (4) and caloxanthone A (5), were isolated from the stem bark of Calophyllum hosei. The structures of these compounds were established by using spectroscopic analysis which included (1)H NMR, (13)C NMR, COSY, DEPT, HMQC and HMBC experiments.

Matched MeSH terms: Coumarins/pharmacology
Fulltext Synthesis and discovery of new bisadducts derived from heterocyclic aldehydes and active methylene compounds as potent antitubercular agents

Asad M, Oo CW, Kumar RS, Osman H, Ali MA

Acta Pol Pharm, 2013 Mar-Apr;70(2):221-8.
PMID: 23614277

A series of some new bisadducts possessing five, six membered and coumarin subunits were synthesized by the condensation of heterocyclic aldehydes with active methylene compounds and characterized by IR, NMR and X-ray crystallographic studies and were assayed as antitubercular agents. Among the bisadducts, 4-hydroxy-3-[(4-hydroxy-2-oxo-2H-3-chromenyl)(3-thienyl)methyl]-2H-2-chromenone 3a was found to be the most promising compound, active against Mycobacterium tuberculosis (Mtb) H37Rv and isoniazid resistant Mycobacterium tuberculosis (INHR-Mtb) with minimum inhibitory concentration 5.22 and 8.34 microM, respectively.

Matched MeSH terms: Coumarins/pharmacology*
Synthesis and antimicrobial properties of some new thiazolyl coumarin derivatives

Arshad A, Osman H, Bagley MC, Lam CK, Mohamad S, Zahariluddin AS

Eur J Med Chem, 2011 Sep;46(9):3788-94.
PMID: 21712145 DOI: 10.1016/j.ejmech.2011.05.044

Two novel series of hydrazinyl thiazolyl coumarin derivatives have been synthesized and fully characterized by IR, (1)H NMR, (13)C NMR, elemental analysis and mass spectral data. The structures of some compounds were further confirmed by X-ray crystallography. All of these derivatives, 10a-d and 15a-h, were screened in vitro for antimicrobial activity against various bacteria species including Mycobacterium tuberculosis and Candida albicans. The compounds 10c, 10d and 15e exhibited very good activities against all of the tested microbial strains.

Matched MeSH terms: Coumarins/pharmacology*
Fulltext Geranylated 4-Phenylcoumarins Exhibit Anticancer Effects against Human Prostate Cancer Cells through Caspase-Independent Mechanism

Suparji NS, Chan G, Sapili H, Arshad NM, In LL, Awang K, et al.

PLoS One, 2016;11(3):e0151472.
PMID: 26974436 DOI: 10.1371/journal.pone.0151472

Geranylated 4-phenylcoumarins, DMDP-1 & -2 isolated from Mesua elegans were investigated for anticancer potential against human prostate cancer cells. Treatment with DMDP-1 & -2 resulted in cell death in a time and dose dependent manner in an MTT assay on all cancer cell lines tested with the exception of lung adenocarcinoma cells. DMDP-1 showed highest cytotoxic efficacy in PC-3 cells while DMDP-2 was most potent in DU 145 cells. Flow cytometry indicated that both coumarins were successful to induce programmed cell death after 24 h treatment. Elucidation on the mode-of-action via protein arrays and western blotting demonstrated death induced without any significant expressions of caspases, Bcl-2 family proteins and cleaved PARP, thus suggesting the involvement of caspase-independent pathways. In identifying autophagy, analysis of GFP-LC3 showed increased punctate in PC-3 cells pre-treated with CQ and treated with DMDP-1. In these cells decreased expression of autophagosome protein, p62 and cathepsin B further confirmed autophagy. In contrary, the DU 145 cells pre-treated with CQ and treated with DMDP-2 has reduced GFP-LC3 punctate although the number of cells with obvious GFP-LC3 puncta was significantly increased in the inhibitor-treated cells. The increase level of p62 suggested leakage of cathepsin B into the cytosol to trigger potential downstream death mediators. This correlated with increased expression of cathepsin B and reduced expression after treatment with its inhibitor, CA074. Also auto-degradation of calpain-2 upon treatment with DMDP-1 &-2 and its inhibitor alone, calpeptin compared with the combination treatment, further confirmed involvement of calpain-2 in PC-3 and DU 145 cells. Treatment with DMDP-1 & -2 also showed up-regulation of total and phosphorylated p53 levels in a time dependent manner. Hence, DMDP-1 & -2 showed ability to activate multiple death pathways involving autophagy, lysosomal and endoplasmic reticulum death proteins which could potentially be manipulated to develop anti-cancer therapy in apoptosis resistant cells.

Matched MeSH terms: Coumarins/pharmacology*
Lepidotol A from Mesua lepidota Inhibits Inflammatory and Immune Mediators in Human Endothelial Cells

Rouger C, Derbré S, Charreau B, Pabois A, Cauchy T, Litaudon M, et al.

J Nat Prod, 2015 Sep 25;78(9):2187-97.
PMID: 26301802 DOI: 10.1021/acs.jnatprod.5b00222

Phytochemical investigation on the fruits of Mesua lepidota (Calophyllaceae) led to the isolation of seven new phenylcoumarin derivatives named lepidotols A-E (1-5) and lepidotins A and B (6, 7). These structures were elucidated by spectroscopic and spectrometric methods including UV, NMR, and HRMS. Lepidotol A (1), the major compound, was evaluated for its inhibitory effect on inflammation and immunity using endothelial cell-based cellular assays. At 10 μM, 1 exhibited an anti-inflammatory activity, with a significant inhibition of vascular cell adhesion molecule 1 and intercellular adhesion molecule 1 expression induced by tumor necrosis factor-α. Lepidotol A also showed a mild immunosuppressive effect, with inhibition of the major histocompatibility complex molecules, namely, human leukocyte antigen (HLA)-DR and HLA-E.

Matched MeSH terms: Coumarins/pharmacology*
Fulltext In silico and in vivo characterization of cabralealactone, solasodin and salvadorin in a rat model: potential anti-inflammatory agents

Malik A, Arooj M, Butt TT, Zahid S, Zahid F, Jafar TH, et al.

Drug Des Devel Ther, 2018;12:1431-1443.
PMID: 29872266 DOI: 10.2147/DDDT.S154169

Background: The present study investigates the hepato- and DNA-protective effects of standardized extracts of Cleome brachycarpa (cabralealactone), Solanum incanum (solasodin), and Salvadora oleioides (salvadorin) in rats.
Materials and methods: Hepatotoxicity was induced with intraperitoneal injection of carbon tetrachloride (CCl4) (1 mL/kg b.wt.) once a week for 12 weeks. The hepato- and DNA protective effects of the extracts in different combinations were compared with that of a standard drug Clavazin (200 mg/kg b.wt.). Tissue alanine aminotransferase, alpha-fetoprotein, tumor necrosis factor alpha (TNF-α), isoprostanes-2α, malondialdehyde, and 8-hydroxydeoxyguanosine, the significant hallmarks of oxidative stress, were studied.
Results: Histopathological findings of the liver sections from the rat group which received CCl4+cabralealactone, solasodin, and salvadorin demonstrated improved centrilobular hepatocyte regeneration with moderate areas of congestion and infiltration comparable with Clavazin. For in silico study, the identified compounds were subjected to molecular docking with cyclooxygenase-2 and TNF-α followed by a molecular dynamics study, which indicated their potential as anti-inflammatory agents.
Conclusion: Cabralealactone, solasodin, and salvadorin confer some hepatoprotective and DNA-damage protective effects against CCl4-induced toxicity. They successfully restored the normal architecture of hepatocytes and have the potential to be used as inhibitor to main culprits, that is, cyclooxygenase-2 and TNF-α. They can combat oxidative stress and liver injuries both as mono and combinational therapies. However, combination therapy has more ameliorating effects.

Matched MeSH terms: Coumarins/pharmacology*
Coumarin-chalcone hybrids targeting insulin receptor: Design, synthesis, anti-diabetic activity, and molecular docking

Konidala SK, Kotra V, Danduga RCSR, Kola PK

Bioorg Chem, 2020 11;104:104207.
PMID: 32947135 DOI: 10.1016/j.bioorg.2020.104207

Four series of thirteen new coumarin-chalcone hybrids (DPCU 1-13, DPCT 1-13, DCCU 1-13 and DCCT 1-13) were designed and synthesized using Biginelli synthesis, Pechmann condensation, Acetylation, and Claisen-Schmidt reactions. Synthesized compounds were tested for insulin receptor in silico docking studies (PDB ID: 1IR3); DCCU 13 and DCCT 13 derivatives received the lowest docking score; Streptozocin (STZ) and Nicotinamide (NA) induced type II diabetes was tested for their anti-diabetic activity in rats. In vivo tests suggested that fasting blood glucose levels of animals treated with DCCU 13 (30 mg/kg body weight) and DCCT 13 (30 mg/kg body weight) were significantly and moderately suppressed, respectively, relative to fasting blood glucose levels of diabetic control animals. Similarly, therapy with DCCU 13 and DCCT 13 attenuated oxidative stress parameters such as lipid peroxidation (MDA), superoxide dismutase (SOD) and increased the glutathione (GSH) in the liver and pancreas in a dose-dependent manner. In comparison, therapy with DCCU 13 (30 mg/kg body weight) mitigated alterations in the histological architecture of the liver and pancreatic tissue. These results indicated that the hybrids DUUC 13 and DCCT 13 at 30 mg/kg had an anti-hyperglycemic and antioxidant impact on STZ + NA mediated type II diabetes in rats. Further detailed work could be required to determine the precise mode of action of the anti-diabetic behavior of hybrids.

Matched MeSH terms: Coumarins/pharmacology*
Fulltext The antioxidant activity of new coumarin derivatives

Kadhum AA, Al-Amiery AA, Musa AY, Mohamad AB

Int J Mol Sci, 2011;12(9):5747-61.
PMID: 22016624 DOI: 10.3390/ijms12095747

The antioxidant activity of two synthesized coumarins namely, N-(4,7-dioxo-2- phenyl-1,3-oxazepin-3(2H,4H,7H)-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 5 and N-(4-oxo-2-phenylthiazolidin-3-yl)-2-(2-oxo-2H-chromen-4-yloxy)acetamide 6 were studied with the DPPH, hydrogen peroxide and nitric oxide radical methods and compared with the known antioxidant ascorbic acid. Compounds 5 and 6 were synthesized in a good yield from the addition reaction of maleic anhydride or mercaptoacetic acid to compound 4, namely N'-benzylidene-2-(2-oxo-2H-chromen-4-yloxy)acetohydrazide. Compound 4 was synthesized by the condensation of compound 3, namely 2-(2-oxo-2H-chromen-4-yloxy) acetohydrazide, with benzaldehyde. Compound 3, however, was synthesized from the addition of hydrazine to compound 2, namely ethyl 2-(2-oxo-2H-chromen-4-yloxy)acetate, which was synthesized from the reaction of ethyl bromoacetate with 4-hydroxycoumarin 1. Structures for the synthesized coumarins 2-6 are proposed on the basis of spectroscopic evidence.

Matched MeSH terms: Coumarins/pharmacology
Tumour necrosis factor alpha down-regulates the expression of peroxisome proliferator activated receptor alpha (PPARα) in human hepatocarcinoma HepG2 cells by activation of NF-κB pathway

Lim WS, Ng DL, Kor SB, Wong HK, Tengku-Muhammad TS, Choo QC, et al.

Cytokine, 2013 Jan;61(1):266-74.
PMID: 23141142 DOI: 10.1016/j.cyto.2012.10.007

Peroxisome proliferator activated receptor-alpha (PPARα) plays a major role in the regulation of lipid and glucose homeostasis, and inflammatory responses. The objectives of the study were to systematically investigate the effects of TNF-α and its regulatory pathway on PPARα expression in HepG2 cells using Real-Time RT-PCR and western blot analysis. Here, TNF-α suppressed PPARα mRNA expression in a dose- and time-dependent manner at the level of gene transcription. Pre-treatment of cells with 10μM of Wedelolactone for 2h was sufficient to restore PPARα expression to basal levels and also affected the expression of PPARα-regulated genes. This study also demonstrated that TNF-α represses PPARα expression by augmenting the activity of canonical NF-κB signalling pathway. This was shown by the abrogation of TNF-α-mediated PPARα down-regulation, after both p65 and p50 were knocked down via siRNA. The IKK contributes to IκBα degradation and mediates inducible phosphorylation of p105 at Ser933. Surprisingly, phosphorylation of p65 at Ser468 and Ser536 were severely abrogated with Wedelolactone inhibition, suggesting that Ser468 and Ser536, but not Ser276, may mediate the TNF-α inhibitory action on PPARα gene expression. These results suggest that TNF-α might, at least in part, suppress PPARα expression through activation of IKK/p50/p105/p65 pathway. Furthermore, phosphorylation of p65 at Ser468 and Ser536 may play a crucial role in the mechanism that limits PPARα production in the human HepG2 cells.

Matched MeSH terms: Coumarins/pharmacology