Design and synthesis of new spirooxindole candidates and their selenium nanoparticles as potential dual Topo I/II inhibitors, DNA intercalators, and apoptotic inducers.

A new wave of dual Topo I/II inhibitors was designed and synthesised via the hybridisation of spirooxindoles and pyrimidines. In situ selenium nanoparticles (SeNPs) for some derivatives were synthesised. The targets and the SeNP derivatives were examined for their cytotoxicity towards five cancer cell lines. The inhibitory potencies of the best members against Topo I and Topo II were also assayed besides their DNA intercalation abilities. Compound 7d NPs exhibited the best inhibition against Topo I and Topo II enzymes with IC50 of 0.042 and 1.172 µM, respectively. The ability of compound 7d NPs to arrest the cell cycle and induce apoptosis was investigated. It arrested the cell cycle in the A549 cell at the S phase and prompted apoptosis by 41.02% vs. 23.81% in the control. In silico studies were then performed to study the possible binding interactions between the designed members and the target proteins.

A new wave of dual Topo I/II inhibitors was designed and synthesised via the hybridisation of spirooxindoles and pyrimidines.In situ selenium nanoparticles (SeNPs) for some derivatives were synthesised.Cytotoxicity, Topo I and Topo II inhibitory assays, and DNA intercalation abilities were evaluated.Compound 7d NPs showed the best Topo I and Topo II inhibition.Cell cycle arrest, apoptosis induction, and molecular docking studies were performed.

Novel pyrimidine Schiff bases and their selenium-containing nanoparticles as dual inhibitors of CDK1 and tubulin polymerase: design, synthesis, anti-proliferative evaluation, and molecular modelling.

Nanotechnology-based strategies can overcome the limitations of conventional cancer therapies. Hence, novel series of pyrimidine Schiff bases (4-9) were employed in the synthesis of selenium nanoparticle forms (4NPs-9NPs). All selenium nano-sized forms exerted greater inhibitions than normal-sized compounds, far exceeding 5-fluorouracil activity. Compound 4 showed effective anti-proliferative activity against MCF-7(IC50 3.14 ± 0.04 µM), HepG-2(IC50 1.07 ± 0.03 µM), and A549(IC50 1.53 ± 0.01 µM) cell lines, while its selenium nanoform 4NPs showed excellent inhibitory effects, with efficacy increased by 96.52%, 96.45%, and 93.86%, respectively. Additionally, 4NPs outperformed 4 in selectivity against the Vero cell line by 4.5-fold. Furthermore, 4NPs exhibited strong inhibition of CDK1(IC50 0.47 ± 0.3 µM) and tubulin polymerase(IC50 0.61 ± 0.04 µM), outperforming 4 and being comparable to roscovitine (IC50 0.27 ± 0.03 µM) and combretastatin-A4(IC50 0.25 ± 0.01 µM), respectively. Moreover, both 4 and 4NPs arrested the cell cycle at G0/G1 phase and significantly forced the cells towards apoptosis. Molecular docking demonstrated that 4 and 4NPs were able to inhibit CDK1 and tubulin polymerase binding sites.

Protective prospects of eco-friendly synthesized selenium nanoparticles using Moringa oleifera or Moringa oleifera leaf extract against melamine induced nephrotoxicity in male rats.

Nanotechnology is used in a wide range of applications, including medical therapies that precisely target disease prevention and treatment. The current study aimed firstly, to synthesize selenium nanoparticles (SeNPs) in an eco-friendly manner using Moringa oleifera leaf extract (MOLE). Secondly, to compare the protective effects of green-synthesized MOLE-SeNPs conjugate and MOLE ethanolic extract as remedies for melamine (MEL) induced nephrotoxicity in male rats. One hundred and five male Sprague Dawley rats were divided into seven groups (n = 15), including 1st control, 2nd MOLE (800 mg/kg BW), 3rd SeNPs (0.5 mg/kg BW), 4th MOLE-SeNPs (200 µg/kg BW), 5th MEL (700 mg/kg BW), 6th MEL+MOLE, and 7th MEL+MOLE SeNPs. All groups were orally gavaged day after day for 28 days. SeNPs and the colloidal SeNPs were characterized by TEM, SEM, and DLS particle size. SeNPs showed an absorption peak at a wavelength of 530 nm, spherical shape, and an average size between 3.2 and 20 nm. Colloidal SeNPs absorption spectra were recorded between 400 and 700 nm with an average size of 3.3-17 nm. MEL-induced nephropathic alterations represented by a significant increase in serum creatinine, urea, blood urea nitrogen (BUN), renal TNFα, oxidative stress-related indices, and altered the relative mRNA expression of apoptosis-related genes Bax, Caspase-3, Bcl2, Fas, and FasL. MEL-induced array of nephrotoxic morphological changes, and up-regulated immune-expression of proliferating cell nuclear antigen (PCNA) and proliferation-associated nuclear antigen Ki-67. Administration of MOLE or MOLE-SeNPs significantly reversed MEL-induced renal function impairments, oxidative stress, histological alterations, modulation in the relative mRNA expression of apoptosis-related genes, and the immune-expression of renal PCNA and Ki-67. Conclusively, the green-synthesized MOLE-SeNPs and MOLE display nephron-protective properties against MEL-induced murine nephropathy. This study is the first to report these effects which were more pronounced in the MOLE group than the green biosynthesized MOLE-SeNPs conjugate group.

Astragalus membranaceus and Punica granatum alleviate infertility and kidney dysfunction induced by aging in male rats.

By aging, male fertility and kidney function decline. Therefore, the investigation of health span-extending agents becomes more urgent to overcome aging-induced infertility and kidney dysfunction. The current research was undertaken to investigate the antiaging efficacy of Astragalus membranaceus telomerase activator-65 (Ta-65) and pomegranate supplements. Forty male Wistar rats were divided into young rats, aged rats, aged rats treated with Ta-65 (500mg/kg/day), and aged rats treated with pomegranate (250mg/kg/day). Testosterone, FSH, LH, and kidney functions were measured in serum. Sperm analysis as well as testicular histological examination was performed. Aging caused an imbalance in male sex hormones resulting in sperm abnormality and reductions in the sperm count and motility. Elevations in serum creatinine, uric acid, sodium, and potassium were reported in aged rats. Treatment with Ta-65 or pomegranate effectively ameliorated all the deteriorations induced by normal aging in male fertility and renal function. Ta-65 and pomegranate possessed strong antiaging activity by alleviating aging-induced male infertility through reestablishing the hormonal balance and testis architecture. They also alleviated the kidney dysfunction. On comparing Ta-65 with pomegranate, the improvement in FSH, LH, and sperm abnormalities caused by Ta-65 was much better than that caused by pomegranate.

Modulatory effect of Prosopis juliflora leaves on hepatic fibrogenic and fibrolytic alterations induced in rats by thioacetamide.

This study investigated the antifibrotic effect of Prosopis juliflora leaves crude methanolic extract (PJEL) against thioacetamide (TAA)-induced liver fibrosis. The phytochemical analysis of PJEL was performed via HPLC/MS in association with evaluating its free radical scavenging and cytotoxic activities. The antifibrotic activity of PJEL was assessed by dividing Wistar rats into 8 groups: normal control, PJEL1-administered rats (2 mg/ Kg b.w.), PJEL2-administered rats (4 mg/ Kg b.w.), PJEL3-administered rats (8 mg/Kg b.w.), TAA-induced hepatic fibrosis, TTA + PJEL1, TAA + PJEL2, and TAA + PJEL3. Results indicated that PJEL crude methanolic extract is rich in polyphenolic compounds and alkaloids. PJEL exerted free radical scavenging activity with IC50 of 123.5 µg/mL and cytotoxic activity against a well-differentiated hepatocellular cell line (IC50 = 11.1 µg/mL). PJEL at a dose of 4 mg/Kg b.w. ameliorated serum ALT activity and improved serum albumin level and hepatic hydroxyproline content in association with a reduction in the fibrosis stage. PJEL elevated hepatic tumor necrosis factor-α and interleukin-6 contents with less necrosis grade. PJEL post-therapy ameliorated the relative expression of Bcl-2, Col1A1, Mmp-9, and Mmp-2 genes in liver. CONCLUSION: PJEL possesses a good therapeutic activity against TAA-induced liver fibrosis via enhancing extracellular matrix removal and stimulating hepatic regeneration to decrease hepatic necrosis.

Ferulsinaic acid attenuation of advanced glycation end products extends the lifespan of Caenorhabditis elegans.

OBJECTIVES: Ferulsinaic acid is the first member of a new rearranged class of sesquiterpene coumarins of the genus Ferula. The genus Ferula can be used for the treatment of skin infections, hysteria and for stomach disorders, such as a febrifuge and a carminative agent. The effect of ferulsinaic acid on the lifespan of the nematode Caenorhabditis elegans has been examined. Novel data explaining the effect of ferulsinaic acid on the lifespan of C. elegans and its antioxidant power were obtained. METHODS: C. elegans was cultivated under standard laboratory conditions in absence and presence of different ferulsinaic acid. Also, animals were cultivated under heat and chemical stress conditions in absence and presence of ferulsinaic acid. Life span assay, determination of protein concentration, assay of malondialdehyde and ELISA for determination of AGEs were performed. KEY FINDINGS: Under standard laboratory conditions and in presence of ferulsinaic acid (500 nm, 10 µm and 100 µm), mean life span of wild type animals was significantly lengthened in a dose-dependent manner from 18.64 ± 0.19 days (control) to 19 ± 0.19 (P = 0.695), 20.76 ± 0.25 (P = 0.043) and 22.3 ± 0.29 (P = 0.0291), respectively. Interestingly, in C. elegans resistance for heat stress at 35°C and oxidative stress induced by paraquat were significantly improved with ferulsinaic acid. Ferulsinaic acid was found to significantly attenuate both lipid peroxidation and the formation of advanced glycation end products in the wild-type animals under standard laboratory conditions. CONCLUSIONS: Ferulsinaic acid had therapeutic efficacy as an antioxidant with the possibility of its use as an antioxidant drug.

Inhibition of Schistosoma mansoni thioredoxin-glutathione reductase by auranofin: structural and kinetic aspects.

Schistosomiasis is a parasitic disease affecting over 200 million people currently treated with one drug, praziquantel. A possible drug target is the seleno-protein thioredoxin-glutathione reductase (TGR), a key enzyme in the pathway of the parasite for detoxification of reactive oxygen species. The enzyme is a unique fusion of a glutaredoxin domain with a thioredoxin reductase domain, which contains a selenocysteine (Sec) as the penultimate amino acid. Auranofin (AF), a gold-containing compound already in clinical use as an anti-arthritic drug, has been shown to inhibit TGR and to substantially reduce worm burden in mice. Using x-ray crystallography we solved (at 2.5 A resolution) the structure of wild type TGR incubated with AF. The electron density maps show that the actual inhibitor is gold, released from AF. Gold is bound at three different sites not directly involving the C-terminal Sec residue; however, because the C terminus in the electron density maps is disordered, we cannot exclude the possibility that gold may also bind to Sec. To investigate the possible role of Sec in the inactivation kinetics, we tested the effect of AF on a model enzyme of the same superfamily, i.e. the naturally Sec-lacking glutathione reductase, and on truncated TGR. We demonstrate that the role of selenium in the onset of inhibition by AF is catalytic and can be mimicked by an external source of selenium (benzeneselenol). Therefore, we propose that Sec mediates the transfer of gold from its ligands in AF to the redox-active Cys couples of TGR.

A 1,536-well-based kinetic HTS assay for inhibitors of Schistosoma mansoni thioredoxin glutathione reductase.

Abstract: Schistosomiasis is a major neglected tropical disease that currently affects over 200 million people and leads to over 200,000 annual deaths. Schistosoma mansoni parasites survive in humans in part because of a set of antioxidant enzymes that continuously degrade reactive oxygen species produced by the host. A principal component of this defense system has been recently identified as thioredoxin glutathione reductase (TGR), a parasite-specific enzyme that combines the functions of two human counterparts, glutathione reductase and thioredoxin reductase, and as such this enzyme presents an attractive new target for anti-schistosomiasis drug development. Herein, we present the development of a highly miniaturized and robust screening assay for TGR. The 5-mul final volume assay is based on the Ellman reagent [5,5'-dithiobis(2-nitrobenzoic acid) (DTNB)] and utilizes a high-speed absorbance kinetic read to minimize the effect of dust, absorbance interference, and meniscus variation. This assay is further applicable to the testing of other redox enzymes that utilize DTNB as a model substrate.

Quantitative high-throughput screen identifies inhibitors of the Schistosoma mansoni redox cascade.

Schistosomiasis is a tropical disease associated with high morbidity and mortality, currently affecting over 200 million people worldwide. Praziquantel is the only drug used to treat the disease, and with its increased use the probability of developing drug resistance has grown significantly. The Schistosoma parasites can survive for up to decades in the human host due in part to a unique set of antioxidant enzymes that continuously degrade the reactive oxygen species produced by the host's innate immune response. Two principal components of this defense system have been recently identified in S. mansoni as thioredoxin/glutathione reductase (TGR) and peroxiredoxin (Prx) and as such these enzymes present attractive new targets for anti-schistosomiasis drug development. Inhibition of TGR/Prx activity was screened in a dual-enzyme format with reducing equivalents being transferred from NADPH to glutathione via a TGR-catalyzed reaction and then to hydrogen peroxide via a Prx-catalyzed step. A fully automated quantitative high-throughput (qHTS) experiment was performed against a collection of 71,028 compounds tested as 7- to 15-point concentration series at 5 microL reaction volume in 1536-well plate format. In order to generate a robust data set and to minimize the effect of compound autofluorescence, apparent reaction rates derived from a kinetic read were utilized instead of end-point measurements. Actives identified from the screen, along with previously untested analogues, were subjected to confirmatory experiments using the screening assay and subsequently against the individual targets in secondary assays. Several novel active series were identified which inhibited TGR at a range of potencies, with IC(50)s ranging from micromolar to the assay response limit ( approximately 25 nM). This is, to our knowledge, the first report of a large-scale HTS to identify lead compounds for a helminthic disease, and provides a paradigm that can be used to jump-start development of novel therapeutics for other neglected tropical diseases.

Ferulsinaic acid, a sesquiterpene coumarin with a rare carbon skeleton from Ferula species.

Fractionation of methylene chloride extracts of the resin of Ferula vesceritensis and F. sinaica afforded three sesquiterpene coumarins and a glucose derivative. One of them was a sesquiterpene with a rare carbon skeleton. The structures of these compounds were determined by extensive NMR studies, including DEPT, COSY, NOE, HMQC, and HMBC.