Design, Synthesis and Molecular Docking of Novel Acetophenone-1,2,3-Triazoles Containing Compounds as Potent Enoyl-Acyl Carrier Protein Reductase (InhA) Inhibitors.

New medications are desperately needed to combat rising drug resistance among tuberculosis (TB) patients. New agents should ideally work through unique targets to avoid being hampered by preexisting clinical resistance to existing treatments. The enoyl-acyl carrier protein reductase InhA of M. tuberculosis is one of the most crucial targets since it is a promising target that has undergone extensive research for anti-tuberculosis drug development. A well-known scaffold for a variety of biological activities, including antitubercular activity, is the molecular linkage of a1,2,3-triazole with an acetamide group. As a result, in the current study, which was aided by ligand-based molecular modeling investigations, 1,2,3-triazolesweredesigned and synthesized adopting the CuAAC aided cycloaddition of 1-(4-(prop-2-yn-1-yloxy)phenyl)ethanone with appropriate acetamide azides. Standard spectroscopic methods were used to characterize the newly synthesized compounds. In vitro testing of the proposed compounds against the InhA enzyme was performed. All the synthesized inhibitors completely inhibited the InhA enzyme at a concentration of 10 µM that exceeded Rifampicin in terms of activity. Compounds 9, 10, and 14 were the most promising InhA inhibitors, with IC50 values of 0.005, 0.008, and 0.002 µM, respectively. To promote antitubercular action and investigate the binding manner of the screened compounds with the target InhA enzyme's binding site, a molecular docking study was conducted.

Novel Hybrid 1,2,4- and 1,2,3-Triazoles Targeting Mycobacterium Tuberculosis Enoyl Acyl Carrier Protein Reductase (InhA): Design, Synthesis, and Molecular Docking.

Tuberculosis (TB) caused by Mycobacterium tuberculosis is still a serious public health concern around the world. More treatment strategies or more specific molecular targets have been sought by researchers. One of the most important targets is M. tuberculosis' enoyl-acyl carrier protein reductase InhA which is considered a promising, well-studied target for anti-tuberculosis medication development. Our team has made it a goal to find new lead structures that could be useful in the creation of new antitubercular drugs. In this study, a new class of 1,2,3- and 1,2,4-triazole hybrid compounds was prepared. Click synthesis was used to afford 1,2,3-triazoles scaffold linked to 1,2,4-triazole by fixable mercaptomethylene linker. The new prepared compounds have been characterized by different spectroscopic tools. The designed compounds were tested in vitro against the InhA enzyme. At 10 nM, the inhibitors 5b, 5c, 7c, 7d, 7e, and 7f successfully and totally (100%) inhibited the InhA enzyme. The IC50 values were calculated using different concentrations. With IC50 values of 0.074 and 0.13 nM, 7c and 7e were the most promising InhA inhibitors. Furthermore, a molecular docking investigation was carried out to support antitubercular activity as well as to analyze the binding manner of the screened compounds with the target InhA enzyme's binding site.

Valproic acid potentiates curcumin-mediated neuroprotection in lipopolysaccharide induced rats.

The etiology of neuroinflammation is complex and comprises multifactorial, involving both genetic and environmental factors during which diverse genetic and epigenetic modulations are implicated. Curcumin (Cur) and valproic acid (VPA), histone deacetylase 1 inhibitor, have neuroprotective effects. The present study was designed with an aim to investigate the ability of co-treatment of both compounds (Cur or VPA, 200 mg/kg) for 4 weeks to augment neuroprotection and enhance brain recovery from intra-peritoneal injection of (250 µg/kg) lipopolysaccharide-stimulated neuroinflammatory condition on rat brain cortex. Cortex activation and the effects of combined treatment and production of proinflammatory mediators, cyclooxygenase-2 (COX-2), APE1, and nitric oxide/inducible nitric oxide synthase (iNOS) were investigated. Neuroinflammation development was assessed by histological analyses and by investigating associated indices [ß-secretase (BACE1), amyloid protein precursor (APP), presenilin (PSEN-1), and PSEN-2)]. Furthermore we measured the expression profile of lethal-7 (let-7) miRNAs members a, b, c, e, and f in all groups, a highly abundant regulator of gene expression in the CNS. Protein and mRNA levels of neuroinflammation markers COX-2, BACE1, APP, and iNOS were also attenuated by combined therapy. On the other hand, assessment of the indicated five let-7 members, showed distinct expression profile pattern in the different groups. Let-7 a, b, and c disappeared in the induced group, an effect that was partially suppressed by co-addition of either Cur or VPA. These data suggest that the combined treatment induced significantly the expression of the five members when compared to rats treated with Cur or VPA only as well as to self-recovery group, which indicates a possible benefit from the synergistic effect of Cur-VPA combination as therapeutic agents for neuroinflammation and its associated disorders. The mechanism elucidated here highlights the particular drug-induced expression profile of let-7 family as new targets for future pharmacological development.

Apurinic/apyrimidinic endonuclease 1 is a key modulator of aluminum-induced neuroinflammation.

BACKGROUND: Chronic administration of Aluminum is proposed as an environmental factor that may affect several enzymes and other biomolecules related to neurotoxicity and Alzheimer's disease (AD). APE1 a multifunctional protein, functions in DNA repair and plays a key role in cell survival versus cell death upon stimulation with cytotoxic agent, making it an attractive emerging therapeutic target. The promising protective effect of resveratrol (resv), which is known to exert potent anti-inflammatory effects on neurotoxicity induced by aluminum chloride (AlCl3), may be derived from its own antioxidant properties. In the present work we investigated the modulation of APE1 expression during AlCl3-induced neuroinflammation (25 mg/Kg body weight by oral gavages) in experimental rats. We tested the hypothesis that a reactive oxygen species (ROS)-scavenger, resveratrol at 0.5 mg/kg bodyweight, which is known to exert potent anti-inflammatory effects, would attenuate central inflammation and modulate APE1 expression in AlCl3-fed rats. Neuroinflammation-induced genes including ß-secretase (BACE), amyloid-ß precursor protein (APP), presenilin 2 (PSEN-2) and sirt-2 were determined by RT-PCR. APE1 is determined at mRNA and protein levels and confirmed by immunohistochemistry. The expression of pro-inflammatory cytokines (TNF-α, IL6) and iNOS by the rat brain extract were measured by RT-PCR. RESULT: Our results indicate that resveratrol may attenuate AlCl3-induced direct neuroinflammation in rats, and its mechanisms are, at least partly, due to maintaining high APE1 level. Resveratrol co-administration with aluminum chloride exerted more protective effect than pre-administration or treatment of induced rats. A significant elevation of APE1 at both mRNA and protein levels was observed in addition to a marked reduction in ß-secretase and amyloid-ß. We found that AlCl3 stimulated the expression of TNF-α, IL-6, and iNOS in rat brain in which NF-κB was involved. Resveratrol inhibited AlCl3-induced expression and release of TNF-α, IL-6, and iNOS in rat brain. CONCLUSIONS: These findings establish a role for APE1 as a master regulator of AlCl3 dependent inflammatory responses in rat brain. In addition, there was an ameliorative change with resveratrol against AlCl3-induced neurotoxicity. These results suggest that rat brain cells produce pro-inflammatory cytokines in response to AlCl3 in a similar pattern, and further suggest that resveratrol exerts anti-inflammatory effects in rat brain, at least partly, by inhibiting different pro-inflammatory cytokines and key signaling molecules. It might be a potential agent for treatment of neuroinflammation-related diseases, such as AD.

Modulation of AP-endonuclease1 levels associated with hepatic cirrhosis in rat model treated with human umbilical cord blood mononuclear stem cells.

Oxidative stress in liver cells may contribute to the etiology of hepatic diseases, as in liver cirrhosis. AP-Endonuclease1 (APE1/Ref-1) is essential for cell protection toward oxidative stress by acting as a transcriptional regulator of pro-survival genes and as a redox sensitive protein. The aim of this study was to critically analyze the various parameters governing the success of human umbilical cord blood mononuclear stem cell-based (MNCs) therapy without the use of an immunosuppressant and to investigate for the first time the expression of APE1 during thioacetamide (TAA)-induced cirrhosis and MNCs therapy in a rat model. Umbilical cord blood samples from full-term deliveries were collected. Lethal fulminant hepatic cirrhosis in rats was induced by intraperitoneal injection of thio-acetamide. MNCs were then intrahepatically transplanted. We measured APE1 expression at mRNA and protein levels, mRNA expression of TGF-ß, α-SMA, STAP, CTGF, MMP-9 and TIMP-1 in a follow up study. Histopathological and immunohistochemical analyses were performed 10 weeks after intrahepatic injection of the cells. Transdifferentiated cells could be efficiently stained with antihuman hepatocytes. Interestingly, human hepatocyte-specific markers, human albumin, cytokeratin-18 and cytokeratin-19 mRNAs were detected in rat liver after 10 days of MNCs infusion. MNC transplanted by intrahepatic route, could engraft recipient liver, differentiated into functional hepatocytes, and rescued liver failure. Moreover up regulation of APE1 expression confirmed by marked immunohistochemical staining may be involved in MNCs-induced hepatocytes regeneration suggesting that maintaining high level of APE1 has protective effect as pro-survival signal.

Alteration of AP-endonuclease1 expression in curcumin-treated fibrotic rats.

BACKGROUND: Apurinic/apyrimidinic endonuclease1/ redox factor-1 (APE1/Ref-1) is a multifunctional protein involved in DNA base excision repair and redox regulation of many transcription factors. It is an important pro-survival protein activated in response to oxidative stress. Increased level of this essential redox sensitive protein correlates closely with cellular survival against oxidative insults. Curcumin (diferuloylmethane) a naturally occurring compound derived from turmeric has attracted interest because of its anti-inflammatory, anti-oxidative, and chemopreventive activities. MATERIAL AND METHODS: The current study evaluates the in vivo role of curcumin in protecting and treating liver injury and fibrogenesis caused by carbon tetrachloride (CCl4) in rats. It also addresses the possible involvement of the multifunctional protein APE1 in hepatoprotection. Analysis of APE1 expression was performed at mRNA and protein levels by reverse transcriptase (RT)-PCR and western blotting respectively. Profile of HSCs-activation related genes were assayed by RT-PCR and pro-inflammatory cytokines levels were determined by enzyme-linked immune assays. RESULTS: Here we show that oral administration of curcumin was accompanied by a robust increase in APE1 protein and mRNA levels, and improved the histological architecture of rat liver. In addition, curcumin attenuated oxidative stress by increasing the content of hepatic glutathione within normal values, leading to the reduction in the level of lipid hydroperoxide. Curcumin remarkably suppressed inflammation by reducing levels of inflammatory cytokines, including tumor necrosis factor-α (TNF-α), nuclear factor-kappa B (NF-κB) and interleukin-6 (IL-6). It also inhibited hepatic stellate cells (HSCs) activation by elevating the level of PPARγ and reducing the abundance of transforming growth factor-ß (TGF-ß). We found that oral administration of curcumin at 200 mg/kg dose not only protected against CCl4-induced hepatic injury, but also resulted in more than two-fold induction of APE1 protein expression in CCl4-induced rat group. CONCLUSIONS: It can be concluded that curcumin reduced markers of liver damage in rats treated with CCl4, with concomitant elevation in APE1 protein level indicating a possible protective effect with unknown mechanism. The induction of DNA repair enzymes may be an important and novel strategy for hepatic protection against oxidative injury.

Succinate cytochrome c reductase in schistosomiasis: in vitro inhibition by some schistosomicidal drugs

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Enzymes in mitochondria play an important role in biological oxidation and energy production. To understand the effect of schistosomiasis on these important processes, succinate cytochrome creductase (SCR) from control and Schistosoma-infected mice was subjected for investigation. In this article, we report that SCR from Schistosoma-infected mouse showed a significant decrease in its Vmax and K m compared to control using both cytochrome c and 2,6-dichlorophenolindophenol as substrates. Furthermore, the kinetic studies of the purified SCR in the absence and presence of the schistosomicidal drugs praziquantel and Commiphora extract reveal that both drugs have an inhibitory action on the enzyme from the control and Schistosoma-infected mice and praziquantel changes the type of inhibition of SCR towards cytochrome c from mixed type in control to a competitive one in the case of the infection (AU)

Succinate cytochrome c reductase in schistosomiasis: in vitro inhibition by some schistosomicidal drugs.

Enzymes in mitochondria play an important role in biological oxidation and energy production. To understand the effect of schistosomiasis on these important processes, succinate cytochrome c reductase (SCR) from control and Schistosoma-infected mice was subjected for investigation. In this article, we report that SCR from Schistosoma-infected mouse showed a significant decrease in its Vmax and Km compared to control using both cytochrome c and 2,6-dichlorophenolindophenol as substrates. Furthermore, the kinetic studies of the purified SCR in the absence and presence of the schistosomicidal drugs praziquantel and Commiphora extract reveal that both drugs have an inhibitory action on the enzyme from the control and Schistosoma-infected mice and praziquantel changes the type of inhibition of SCR towards cytochrome c from mixed type in control to a competitive one in the case of the infection.

Conversion of some 2(3H)-furanones bearing a pyrazolyl group into other heterocyclic systems with a study of their antiviral activity.

3-(1,3-diphenylpyrazol-4-yl-methylene)-5-aryl-2(3H)-furanones 2 were prepared and converted into a variety of heterocyclic systems of synthetic and biological importance. Benzylamine reacted with the furanones 2; the product was found to depend on the reaction conditions. Thus, at room temperature the open-chain N-benzylamides 3 were obtained, whereas under refluxing conditions the 2(3H)-pyrrolones were obtained. Hydrazine hydrate affected ring opening of the furanones to give the corresponding acid hydrazides 5. The latter products were used as key starting materials for the synthesis of pyridazinones 7 and 8, 1,3,4-oxadiazoles 11 and 13 and 1,2,4-triazoles 12 and 14 all bearing pyrazolyl moiety as a side-chain. Evaluation of antiviral activity of selected examples of the compounds obtained was performed using two viruses: HAV and HSV-1. Some of the tested compounds showed promising activities.

Activity of some hepatic enzymes in schistosomiasis and concomitant alteration of arylsulfatase B.

The levels of arylsulfatases A and B, alpha-amylase, aspartate transcarbamylase, and gamma-glutamyl transpeptidase were investigated during the infection of mice with schistosoma mansoni. This infection caused a significant (p < 0.001) increase in the activity of hepatic arylsulfatase B (ASB), aspartate transcarbamylases and gamma-glutamyl transpeptidase. A non-significant difference occurred for alpha-amylase (p < 0.3) and arylsulfatase A (p > 0.5) when compared to the control. The specific activity of hepatic ASB was progressively increased with the progression of the Schistosoma-infection. Moreover, the kinetic studies of hepatic ASB in Schistosoma-infection showed that a slight decrease in the value of K(m) and about a 40% increase in V(max) when compared to the control. In addition, the pH optimum of hepatic ASB was altered from 6 to 7 as a result of schistosomiasis. These observations suggest that there are schistosomiasis-associated changes of the catalytic and kinetic properties of hepatic ASB.

Biosorption of heavy metals from waste water using Pseudomonas sp

Biosorption experiments for Cr(VI), Cu(II), Cd(II) and Ni(II) were investigated in this study using nonliving biomass of different Pseudomonas species. The applicability of the Langmuir and Freundlich models for the different biosorbent was tested. The coefficient of determination (R²) of both models were mostly greater than 0.9. In case of Ni(II) and Cu(II), their coefficients were found to be close to one. This indicates that both models adequately describe the experimental data of the biosorption of these metals. The maximum adsorption capacity was found to be the highest for Ni followed by Cd(II), Cu(II) and Cr(VI). Whereas the Freundlich constant k in case of Cd(II) was found to be greater than the other metals. Maximum Cr(VI) removal reached around 38 percent and its removal increased with the increase of Cr(VI) influent. Cu(II) removal was at its maximum value in presence of Cr(VI) as a binary metal, which reached 93 percent of its influent concentration. Concerning to Cd(II) and Ni(II) similar removal ratios were obtained, since it was ranged between 35 to 88 percent and their maximum removal were obtained in the case of individual Cd(II) and Ni(II).

DNA single strand breaks induced by low levels of occupational exposure to styrene: the gap between standards and reality.

Styrene is a known mutagen and suspected carcinogen, used in the reinforced plastic industry. This study aims to identify the occurrence of DNA single strand breaks (SSBs) in workers exposed to styrene levels far below the recommended standards. We compared 26 exposed workers with 26 control subjects and found a significant increase in the incidence of DNA-SSBs in the exposed individuals. The levels of the biological indices of exposure (urinary mandelic and phenyl glyoxylic acids) were less than 25% of the recommended limits. Reduction of the threshold limit values/time-weighted-average (TLV-TWA) applied is strongly recommended.