Untargeted metabolomics to discriminate liver and lung hydatid cysts: Importance of metabolites involved in the immune response.

The Echinococcus granulosus sensu lato species complex is responsible for the neglected zoonotic disease known as cystic echinococcosis (CE). Humans and livestock are infected via fecal-oral transmission. CE remains prevalent in Western China, Central Asia, South America, Eastern Africa, and the Mediterranean. Approximately one million individuals worldwide are affected, influencing veterinary and public health, as well as social and economic matters. The infection causes slow-growing cysts, predominantly in the liver and lungs, but can also develop in other organs. The exact progression of these cysts is uncertain. This study aimed to understand the survival mechanisms of liver and lung CE cysts from cattle by determining their metabolite profiles through metabolomics and multivariate statistical analyses. Non-targeted metabolomic approaches were conducted using quadrupole-time-of-flight liquid chromatography/mass spectrometry (LC-QTOF-MS) to distinguish between liver and lung CE cysts. Data processing to extract the peaks on complex chromatograms was performed using XCMS. PCA and OPLS-DA plots obtained through multiple statistical analyses showed interactions of metabolites within and between groups. Metabolites such as glutathione, prostaglandin, folic acid, and cortisol that cause different immunological reactions have been identified both in liver and lung hydatid cysts, but in different ratios. Considering the differences in the metabolomic profiles of the liver and lung cysts determined in the present study will contribute research to enlighten the nature of the cyst and develop specific therapeutic strategies.

Assessing the Potential Apoptotic Effects of Different Hydatid Cyst Fluids on Human Healthy Hepatocytes and Hepatocellular Carcinoma Cells.

Cystic Echinococcosis (CE) is a zoonotic infection caused by the larval form of Echinococcus granulosus in humans. Emerging evidence suggests an intriguing inverse association between E. granulosus infection and the occurrence of cancer. This study aimed to investigate the influence of diverse host-derived hydatid cyst fluids (HCF) with distinct genotypes on human liver hepatocytes (HC) and hepatocellular carcinoma cells (HepG2). Specifically, we examined their effects on cell proliferation, apoptosis sensitivity (BAX/BCL-2), apoptosis-related p53 expression, and the expression of cancer-related microRNA (hsa-miR-181b-3p). Cell proliferation assays, real-time PCR, and ELISA studies were conducted to evaluate potential anti-cancer properties. The findings revealed that animal-origin HCF (G1(A)) induced direct cell death by augmenting the susceptibility of HepG2 cells to apoptosis. Treatment with both G1(A) and G1(H) HCF sensitized HepG2 and HC cell lines to apoptosis by modulating the BAX/BCL-2 ratio, accompanied by upregulation of the p53 gene. Additionally, G1(A) HCF and human-derived HCFs (G1(H), G7(H)) reduced the expression of miR-181b-3p in HepG2 cells. Consequently, this study demonstrates the potential anti-cancer effect of HCF in HepG2 cells and provides the first comparative assessment of HCFs from human and animal sources with diverse genotypes, offering novel insights into this field.

Recent progress in drug delivery systems for tyrosine kinase inhibitors in the treatment of lung cancer.

Lung cancer ranks as the second most commonly diagnosed cancer in both men and women worldwide. Despite the availability of diverse diagnostic and treatment strategies, it remains the leading cause of cancer-related deaths globally. The current treatment approaches for lung cancer involve the utilization of first generation (e.g., erlotinib, gefitinib) and second generation (e.g., afatinib) tyrosine kinase inhibitors (TKIs). These TKIs exert their effects by inhibiting a crucial enzyme called tyrosine kinase, which is responsible for cell survival signaling. However, their clinical effectiveness is hindered by limited solubility and oral bioavailability. Nanotechnology has emerged as a significant application in modern cancer therapy. Nanoparticle-based drug delivery systems, including lipid, polymeric, hybrid, inorganic, dendrimer, and micellar nanoparticles, have been designed to enhance the bioavailability, stability, and retention of these drugs within the targeted lung area. Furthermore, these nanoparticle-based delivery systems offer several advantages, such as increased therapeutic efficacy and reduced side effects and toxicity. This review focuses on the recent advancements in drug delivery systems for some of the most important TKIs, shedding light on their potential in improving lung cancer treatment.

Omic Studies on In Vitro Cystinosis Model: siRNA-Mediated CTNS Gene Silencing in HK-2 Cells.

Cystinosis is an autosomal recessive disease caused by mutations in the CTNS gene encoding a protein called cystinosine, which is a lysosomal cystine transporter. Disease-causing mutations lead to accumulation of cystine crystals in the lysosomes, thereby causing dysfunction of vital organs. Determination of the increased leukocyte cystine level is one of the most used methods for diagnosis. However, this method is expensive, difficult to perform, and may yield different results in different laboratories. In this study, a disease model was created with CTNS gene-silenced HK2 cells, which can mimic cystinosis in cell culture, and multiomics methods (ie, proteomics, metabolomics, and fluxomics) were implemented at this cell culture to investigate new biomarkers for the diagnosis. CTNS-silenced cell line exhibited distinct metabolic profiles compared with the control cell line. Pathway analysis highlighted significant alterations in various metabolic pathways, including alanine, aspartate, and glutamate metabolism; glutathione metabolism; aminoacyl-tRNA biosynthesis; arginine and proline metabolism; beta-alanine metabolism; ascorbate and aldarate metabolism; and histidine metabolism upon CTNS silencing. Fluxomics analysis revealed increased cycle rates of Krebs cycle intermediates such as fumarate, malate, and citrate, accompanied by enhanced activation of inorganic phosphate and ATP production. Furthermore, proteomic analysis unveiled differential expression levels of key proteins involved in crucial cellular processes. Notably, peptidyl-prolyl cis-trans isomerase A, translation elongation factor 1-beta (EF-1beta), and 60S acidic ribosomal protein decreased in CTNS-silenced cells. Additionally, levels of P0 and tubulin α-1A chain were reduced, whereas levels of 40S ribosomal protein S8 and Midasin increased. Overall, our study, through the utilization of an in vitro cystinosis model and comprehensive multiomics approach, led to the way toward the identification of potential new biomarkers while offering valuable insights into the pathogenesis of cystinosis.

Development and In Vitro Evaluation of Crizotinib-Loaded Lipid-Polymer Hybrid Nanoparticles Using Box-Behnken Design in Non-small Cell Lung Cancer.

The goal of the study was to produce, optimize, characterize, and compare crizotinib-loaded lipid-polymer hybrid nanoparticles (CL-LPHNPs), representing a novel contribution to the existing literature, and to determine their anticancer activity in non-small cell lung cancer cells (NSCLC). Box-Behnken design was used to investigate the effect of three independent variables: polymer amount (X1), soy phosphatidylcholine (X2), and DSPE-PEG (X3), on three responses: particle size (Y1), polydispersity index (Y2), and zeta potential (Y3). Different parameters were evaluated on the optimized LPHNP formulations such as encapsulation efficiency, drug release study, transmission electron microscopy (TEM) image analysis, and in vitro cell evaluations. The mean particle size of the optimized formulation is between 120 and 220 nm with a PDI< 0.2 and a zeta potential of -10 to -15 mV. The encapsulation efficiency values of crizotinib-loaded PLGA-LPHNPs (CL-PLGA-LPHNPs) and crizotinib-loaded PCL-LPHNPs (CL-PCL-LPHNPs) were 79.25±0.07% and 70.93±1.81%, respectively. Drug release study of CL-PLGA-LPHNPs and CL-PCL-LPHNPs showed a controlled and sustained release pattern as a result of core-shell type. Additionally, after 48 h, CL-PLGA-LPHNPs and CL-PCL-LPHNPs significantly reduced the viability of NCI-H2228 cells compared to free crizotinib. Moreover, CL-PLGA-LPHNPs and CL-PCL-LPHNPs exhibited a significant decrease in RAS, RAF, MEK, and ERK gene/protein expression levels after 48-h incubation. In conclusion, this pioneering study introduces lipid-polymer hybrid nanoparticles containing crizotinib as a novel treatment approach, uniting the advantages of a polymeric core and a lipid shell. The successful formulation optimization using Box-Behnken design yielded nanoparticles with adjustable size, remarkable stability, high drug loading, and a customizable drug release profile. Extensive investigations of key parameters, including particle size, PDI, ZP, TEM analysis, drug release, EE%, and in vitro evaluations, validate the potential of these nanoparticles. Moreover, the examination of two different polymers, PLGA and PCL, highlights their distinct impacts on nanoparticle performance. This research opens up new prospects for advanced therapeutic interventions with lipid-polymer hybrid nanoparticles.

Metabolomic Analyses to Identify Candidate Biomarkers of Cystinosis.

Cystinosis is a rare, devastating hereditary disease secondary to recessive CTNS gene mutations. The most commonly used diagnostic method is confirmation of an elevated leukocyte cystine level; however, this method is expensive and difficult to perform. This study aimed to identify candidate biomarkers for the diagnosis and follow-up of cystinosis based on multiomics studies. The study included three groups: newly-diagnosed cystinosis patients (patient group, n = 14); cystinosis patients under treatment (treatment group, n = 19); and healthy controls (control group, n = 30). Plasma metabolomics analysis identified 10 metabolites as candidate biomarkers that differed between the patient and control groups [L-serine, taurine, lyxose, 4-trimethylammoniobutanoic acid, orotic acid, glutathione, PE(O-18:1(9Z)/0:0), 2-hydroxyphenyl acetic acid, acetyl-N-formil-5-metoxikinuramine, 3-indoxyl sulphate]. As compared to the healthy control group, in the treatment group, hypotaurine, phosphatidylethanolamine, N-acetyl-d-mannosamine, 3-indolacetic acid, p-cresol, phenylethylamine, 5-aminovaleric acid, glycine, creatinine, and saccharic acid levels were significantly higher, and the metabolites quinic acid, capric acid, lenticin, xanthotoxin, glucose-6-phosphate, taurine, uric acid, glyceric acid, alpha-D-glucosamine phosphate, and serine levels were significantly lower. Urinary metabolomic analysis clearly differentiated the patient group from the control group by means of higher allo-inositol, talose, glucose, 2-hydroxybutiric acid, cystine, pyruvic acid, valine, and phenylalanine levels, and lower metabolite (N-acetyl-L-glutamic acid, 3-aminopropionitrile, ribitol, hydroquinone, glucuronic acid, 3-phosphoglycerate, xanthine, creatinine, and 5-aminovaleric acid) levels in the patient group. Urine metabolites were also found to be significantly different in the treatment group than in the control group. Thus, this study identified candidate biomarkers that could be used for the diagnosis and follow-up of cystinosis.

Separation of the enantiomers of underivatized amino acids by using serially connected dual column high-performance liquid chromatography-tandem mass spectrometry.

In this article, a serially connected dual column liquid chromatography-tandem mass spectrometry (LC-MS/MS) method is described for the simultaneous separation and enantioseparation of proteinogenic amino acids. For this purpose, different achiral and chiral stationary phases (CSP) and mobile phase compositions have been tested. As a result of the optimization studies, the best enatioseparation for amino acids were achieved with a combination of zwitterionic and crown ether stationary phases using a gradient of two mobile phases: A (water:TFA 99.5:0.5, % v/v) and B (acetonitrile:ethanol:TFA 85:15:0.5, % v/v/v). The developed method provided simultaneous enantioseparation of all proteinogenic amino acids under this study including isomeric and isobaric ones except for proline. The method was successfully applied to human lung adenocarcinoma cells (A549) and healthy human lung epithelial cells (BEAS-2B) cultivated with d-amino acid containing cocktails in order to evaluate d-amino acids transfer rate in normal and cancer lines. Thed/l amino acid ratios were different in cancer and normal cell lines cultivated as mentioned above for aspartic acid, cysteine, methionine, phenylalanine, and serine.

Evaluation of Potential Inflammatory Markers for Cystic Echinococcosis: P-selectin and Resistin

Objective: Cystic echinococcosis (CE) is one of the most common zoonotic diseases worldwide. Diagnosis of CE is predominantly based on imaging techniques and serological tests are used in cases of non-characteristic imaging findings as diagnostic reference. However, serological test results cannot be completely reliable as they are affected by multi-factors. P-selectin and resistin are inflammatory markers that are altered during the acute stages of infection. In this purpose, inflammatory markers as P-selectin and resistin have been investigated for a potential diagnostic reference for CE diagnosis. Methods: A total of 60 patients who were diagnosed with CE and twenty-five healthy individuals were included in this study. Blood samples were obtained from all participants. Obtained sera were evaluated using the P-selectin and resistin ELISA kits for protein levels. Additionally, the relative expression of SELP (P-selectin) and RETN (resistin) genes were determined using the comparative CT (ΔΔCT) method between groups as CE patients with active and inactive cysts, CE patients and healthy controls. Results: SELP (13.9-fold change, p<0.05) and RETN (8.1-fold change, p<0.05) were differentially expressed in CE patients compared in the control group. Whereas resistin protein levels were significantly higher in CE patients than the healthy controls (p<0.001), the difference in P-selectin protein levels was not significant (p>0.05). There was no difference between active and inactive CE patients in terms of P-selectin and resistin in gene and protein levels (p>0.05). Conclusion: Although there was no difference between the active and inactive CE patients, the good differentiation between the healthy controls and the CE patients suggested that resistin is a potential inflammatory diagnostic reference.

Efficacy of siRNA-loaded nanoparticles in the treatment of K-RAS mutant lung cancer in vitro.

To design and develop K-RAS silencing small interfering RNA (siRNA)-loaded poly (D, L-lactic-co-glycolic acid) nanoparticles and evaluate their efficacy in the treatment of K-RAS mutant lung cancer. The nanoparticles prepared by the double emulsion solvent evaporation method were characterized by TEM, FTIR and XPS analyzes and evaluated in vitro by XTT, PCR, ELISA, and Western-Blot. Metabolomic analyzes were performed to evaluate the changes in metabolic profiles of the cells after nanoparticles treatment. The nanoparticles were obtained with a particle size less than 250 nm, a polydispersity index around 0.1, a surface charge of (-12) - (+14) mV, and 80% of the siRNA encapsulation. The nanoparticles didn't affect cell viability of the cells after 72 hours. In cancer cells, KRAS expression was decreased by up to 50%, protein levels were decreased by more than 90%. The formulated siRNA delivery nanoparticles can be promising treatment in lung cancer.

Can parasite-derived microRNAs differentiate active and inactive cystic echinococcosis patients?

Cystic Echinococcosis (CE) is a neglected zoonotic disease caused by the metacestode form of Echinococcus granulosus sensu lato. Non-invasive imaging techniques, especially ultrasound, are primarily used for CE diagnosis. MicroRNAs (miRNAs) are small, non-coding RNA molecules that act as post-transcriptional regulators in various biological processes. After identification of parasite-derived miRNAs, these miRNAs are considered to be potential biomarkers for diagnosis and follow-up. The focus of this research is to compare the expression profiles of certain parasite-derived miRNAs in CE patients with active and inactive cysts as well as healthy controls. Parasite-derived miRNAs, egr-let-7-5p, egr-miR-71a-5p, and egr-miR-9-5p, of inactive CE patients were found to be differentially expressed with 3.74-, 2.72-, and 20.78-fold change (p < 0.05), respectively, when compared with active CE patients. In this study, we evaluated for the first time the expression profile of three parasite-derived miRNAs in the serum of CE patients to determine their potential to distinguish between active and inactive CE. It was concluded that serum levels of parasite-derived miRNAs, egr-let-7-5p and egr-miR-9-5p, could be promising new potential biomarkers for stage-specific diagnosis of CE. Further studies are needed with larger sample set to validate discriminating potential of these miRNAs.

Identification of Phenolic Compounds by LC-MS/MS and Evaluation of Bioactive Properties of Two Edible Halophytes: Limonium effusum and L. sinuatum.

This work aimed to evaluate the phenolic content and in vitro antioxidant, antimicrobial and enzyme inhibitory activities of the methanol extracts and their fractions of two edible halophytic Limonium species, L. effusum (LE) and L. sinuatum (LS). The total phenolic content resulted about two-fold higher in the ethyl acetate fraction of LE (522.82 ± 5.67 mg GAE/g extract) than in that of LS (274.87 ± 1.87 mg GAE/g extract). LC-MS/MS analysis indicated that tannic acid was the most abundant phenolic acid in both species (71,439.56 ± 3643.3 µg/g extract in LE and 105,453.5 ± 5328.1 µg/g extract in LS), whereas hyperoside was the most abundant flavonoid (14,006.90 ± 686.1 µg/g extract in LE and 1708.51 ± 83.6 µg/g extract in LS). The antioxidant capacity was evaluated by DPPH and TAC assays, and the stronger antioxidant activity in ethyl acetate fractions was highlighted. Both species were more active against Gram-positive bacteria than Gram negatives and showed considerable growth inhibitions against tested fungi. Interestingly, selective acetylcholinesterase (AChE) activity was observed with LE and LS. Particularly, the water fraction of LS strongly inhibited AChE (IC50 = 0.199 ± 0.009 µg/mL). The ethyl acetate fractions of LE and LS, as well as the n-hexane fraction of LE, exhibited significant antityrosinase activity (IC50 = 245.56 ± 3.6, 295.18 ± 10.57 and 148.27 ± 3.33 µg/mL, respectively). The ethyl acetate fraction and methanol extract of LS also significantly inhibited pancreatic lipase (IC50 = 83.76 ± 4.19 and 162.2 ± 7.29 µg/mL, respectively). Taken together, these findings warrant further investigations to assess the potential of LE and LS as a bioactive source that can be exploited in pharmaceutical, cosmetics and food industries.

Metabolomic profiling of active and inactive liver cystic echinococcosis.

Cystic Echinococcosis (CE) is one of the life-threatening diseases worldwide. It is a parasitic zoonosis caused by tapeworms of the species Echinococcus granulosus sensu lato (s.l). The treatment options of CE vary from simple "watch and wait" approach to invasive treatment, based on the type and especially the nature of the cyst (active/inactive). Serological tests are inadequate to distinguish between active and inactive CE. A diagnostic reference that can determine whether the cyst is active or inactive can easily guide the treatment strategy. We aimed to test whether gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-quadropole time of flight mass spectrometry (LC-qTOF-MS) based metabolomics can establish a plasma metabolic fingerprint of CE patients and identify a diagnostic reference to discriminate active and inactive CE cysts. Metabolite concentrations were measured in plasma samples of 36 active CE patients, 17 inactive CE patients and 31 healthy controls. Multivariate statistical analysis on 232 identified metabolites obtained from two analytical platforms was performed by using principle component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) methods. The PLS-DA scores plot of the combined data set demonstrated a good separation between the groups. Compared to the healthy control group, decreased levels of squalene and increased levels of glyceric acid, 3-phosphoglycerate, glutamic acid, palmitoleic acid and oleic acid were determined in the CE patients. However, decreased levels of 3-phosphoglycerate and increased levels of 4-hydroxyphenylacetylglutamine, docosahexanoic acid were determined in active CE patients compared to the inactive CE patients. Determination of differences in metabolites may provide detailed understandings of potential metabolic process associated with active and inactive CE patients, and altered specific metabolic changes may provide some clues to obtain diagnostic reference for CE. This study has certain limitations: a. various factors affecting results of metabolomic studies such as lifestyle and dietary habits of the patients could not be fully controlled b. other infectious or malignant diseases of the liver should also be included as a positive control to evaluate the specificity of the diagnostic references.

[Evaluation of the Effect of Hydatid Cyst Fluid on the Apoptosis Pathway in BEAS-2B and A549 Cell Lines]. / BEAS-2B ve A549 Hücre Hatlarinda Hidatik Kist Sivisinin Apoptoz Yolagi Üzerine Etkisinin Degerlendirilmesi.

Some of the pathogenic microorganisms have been associated with cancer due to the activation of cancer precursors in the host because of the inflammatory processes. Additionally, some other pathogens prevents the tumor formation by creating an anti-neoplastic immune response which has been reported to stop the development of cancer. Cystic echinococcosis (CE) or cyst hydatid disease (CHD) is a zoonotic infection caused by the larval form of Echinococcus granulosus sensu lato in humans. It has been reported that there is a negative correlation between E.granulosus infection and cancer and it has been suggested that direct and/or indirect E.granulosus infection may have an anti-cancer effect. However, the molecular mechanisms of this effect still remains unclear. The aim of this study was to evaluate the effect of hydatid cyst fluid administration on cell proliferation and expression of some apoptotic genes (BCL-2, p53 and BAX) in human healthy lung epithelial (BEAS-2B) and human lung adenocarcinoma (A549) cell lines and understanding the molecular mechanism underlying the possible anti-cancer action mechanism of hydatid cyst fluid. In order to evaluate the effect of hydatid cyst fluid on cell proliferation and apoptotic gene expression, cell proliferation assay (XTT) and real-time polymerase chain reaction (Rt-PCR) were performed, respectively. After the application of hydatid cyst fluid, there was no change in the cell proliferation. A statistically significant decrease in BCL-2 gene expression (> 90 fold) and an increase in p53 gene expression (> 1.2 fold) were found. No significant change in BAX gene expression was detected. In this study, it was found that the application of hydatid cyst fluid did not directly cause cell death but it has shown for the first time to sensitize the A549 cell line, which is resistant to apoptosisand shed light on the possible mechanism of hydatid cyst fluid in the apoptotic pathway.

Gas chromatography-mass spectrometry based 18O stable isotope labeling of Krebs cycle intermediates.

New technologies permit determining metabolomic profiles of human diseases by fingerprinting metabolites levels. However, to fully understand metabolomic phenotypes, metabolite levels and turnover rates are necessary to know. Krebs cycle is the major hub of energy metabolism and cell signaling. Traditionally, 13C stable isotope labeled substrates were used to track the carbon turnover rates in Krebs cycle metabolites. In this study, for the first time we introduce H2[18O] based stable isotope marker that permit tracking oxygen exchange rates in separate segments of Krebs cycle. The chromatographic and non-chromatographic parameters were systematically tested on the effect of labeling ratio of Krebs cycle mediators to increase selectivity and sensitivity of the method. We have developed a rapid, precise, and robust GC-MS method for determining the percentage of 18O incorporation to Krebs cycle metabolites. The developed method was applied to track the cancer-induced shift in the Krebs cycle dynamics of Caco-2 cells as compared to the control FHC cells revealing Warburg effects in Caco-2 cells. We demonstrate that unique information could be obtained using this newly developed 18O-labeling analytical technology by following the oxygen exchange rates of Krebs cycle metabolites. Thus, 18O-labeling of Krebs cycle metabolites expands the arsenal of techniques for monitoring the dynamics of cellular metabolism. Moreover, the developed method will allow to apply the 18O-labeling technique to numerous other metabolic pathways where oxygen exchange with water takes place.

Identification of Indole-Based Chalcones: Discovery of a Potent, Selective, and Reversible Class of MAO-B Inhibitors.

A series of 11 indole-based chalcones (IC1-11) with various electron donating and withdrawing groups at the para position of the phenyl ring B were synthesized. All the compounds were tested for their human monoamine oxidase (hMAO)-A and hMAO-B inhibitory potencies. Most of the synthesized candidates proved to be potent and selective inhibitors of MAO-B rather than MAO-A, with a reversible and competitive mode. Among them, compound IC9 was found to be a potent inhibitor of hMAO-B with Ki = 0.01 ± 0.005 µM and a selectivity index of 120. It was found to be better than the standard drug, selegiline (hMAO-B with Ki = 0.20 ± 0.020 µM) with a selectivity index of 30.55. PAMPA assays were carried out for all the compounds in order to evaluate the capacity of the compounds to cross the blood-brain barrier. Moreover, the most potent MAO-B inhibitor, IC9, was nontoxic at 5 and 25 µM, with 95.20 and 69.17% viable cells, respectively. The lead compound IC9 has an antioxidant property of 1.18 Trolox equivalents by ABTS assay. Molecular modeling studies were performed against hMAO-B to observe binding site interactions of the lead compound.

Exploration of chlorinated thienyl chalcones: A new class of monoamine oxidase-B inhibitors.

Chalcone has been reported to be a valid scaffold for the design of monoamine oxidase (MAO) inhibitors. This scenario has amplified the momentum for the discovery of heteroaryl based chalcone MAO inhibitors. In the present study, we have synthesized a series of eleven chlorinated thienyl chalcone derivatives substituted with a different functional groups at the para- position on the ring B and investigated for their ability to inhibit human MAO-A and -B. With the exception of compound (2E)-1-(4-chlorocyclopenta-1,3-dien-1-yl)-3-(4-nitrophenyl)prop-2-en-1-one (TC7), which was a selective MAO-A inhibitor, all the other derivatives inhibited hMAO-B potently and selectively with competitive mode of inhibition. The most potent compound (2E)-1-(4-chlorocyclopenta-1,3-dien-1-yl)-3-(4-ethylphenyl)prop-2-en-1-one (TC6) was found to be the best activity and higher selectivity towards hMAO-B with Ki and SI values of 0.31±0.02µM and 16.84, respectively. All the compounds presented in the current study are completely non-toxic with 74-88% viable cells to hepatic cells at 100µM concentration. Molecular docking and molecular dynamics simulation studies were carried out using Autodock-4.2 and Amber 14 to understand the molecular level interaction and energy relation of MAO isoforms with selective MAO-B inhibitor TC6.

Synthesis, Biochemistry, and Computational Studies of Brominated Thienyl Chalcones: A New Class of Reversible MAO-B Inhibitors.

A series of (2E)-1-(5-bromothiophen-2-yl)-3-(para-substituted phenyl)prop-2-en-1-ones (TB1-TB11) was synthesized and tested for inhibitory activity toward human monoamine oxidase (hMAO). All compounds were found to be competitive, selective, and reversible toward hMAO-B except (2E)-1-(5-bromothiophen-2-yl)-3-(4-nitrophenyl)prop-2-en-1-one (TB7) and (2E)-1-(5-bromothiophen-2-yl)-3-(4-chlorophenyl)prop-2-en-1-one (TB8), which were selective inhibitors of hMAO-A. The most potent compound, (2E)-1-(5-bromothiophen-2-yl)-3-[4-(dimethylamino)phenyl]prop-2-en-1-one (TB5), showed the best inhibitory activity and higher selectivity toward hMAO-B, with Ki and SI values of 0.11±0.01 µm and 13.18, respectively. PAMPA assays for all compounds were carried out in order to evaluate the capacity of the compounds to cross the blood-brain barrier. Moreover, the most potent MAO-B inhibitor, TB5, was found to be nontoxic at 5 and 25 µm, with 95.75 and 84.59 % viability among cells, respectively. Molecular docking simulations were carried out to understand the crucial interactions responsible for selectivity and potency.