Evaluation of the Novel Synthetic Tyrosinase Inhibitor (Z)-3-(3-bromo-4-hydroxybenzylidene)thiochroman-4-one (MHY1498) In Vitro and In Silico

Tyrosinase is a key enzyme in melanin synthesis, catalyzing the initial rate-limiting steps of melanin synthesis. Abnormal and excessive melanin synthesis is the primary cause of serious skin disorders including melasma, senile lentigo, freckles, and age spots. In attempts to find potent and safe tyrosinase inhibitors, we designed and synthesized a novel compound, (Z)-3-(3-bromo-4-hydroxybenzylidene)thiochroman-4-one (MHY1498), and evaluated its tyrosinase inhibitory activity in vitro and in silico. The chemical structures of (Z)-3-benzylidenethiochroman-4-one analogues, including the novel compound MHY1498, were rationally designed and synthesized as hybrid structures of reported potent tyrosinase inhibitors, which were confirmed both in vitro and in vivo: (Z)-5-(substituted benzylidene)thiazolidine-2,4-diones (Compound A) and 2-(substituted phenyl)benzo[d]thiazoles (Compound B). During screening, MHY1498 showed a strong dose-dependent inhibitory effect on mushroom tyrosinase. The IC50 value of MHY1498 (4.1 ± 0.6 μM) was significantly lower than that of the positive control, kojic acid (22.0 ± 4.7 μM). In silico molecular multi-docking simulation and inhibition mechanism studies indicated that MHY1498 interacts competitively with the tyrosinase enzyme, with greater affinity for the active site of tyrosinase than the positive control. Furthermore, in B16F10 melanoma cells treated with α-melanocyte-stimulating hormone, MHY1498 suppressed both melanin production and tyrosinase activity. In conclusion, our data demonstrate that MHY1498, a synthesized novel compound, effectively inhibits tyrosinase activity and has potential for treating hyperpigmentation and related disorders.

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Novel Anti-Melanogenic Compounds, (Z)-5-(Substituted Benzylidene)-4-thioxothiazolidin-2-one Derivatives: In Vitro and In Silico Insights

Molecules ◽

10.3390/molecules26164963 ◽

2021 ◽

Vol 26 (16) ◽

pp. 4963

Author(s):

Heejeong Choi ◽

Il Young Ryu ◽

Inkyu Choi ◽

Sultan Ullah ◽

Hee Jin Jung ◽

...

Keyword(s):

Active Site ◽

Kojic Acid ◽

Docking Simulation ◽

Tyrosinase Activity ◽

In Vitro Assays ◽

Mushroom Tyrosinase ◽

Tyrosinase Inhibitors ◽

Melanin Contents ◽

Human Tyrosinase

To confirm that the β-phenyl-α,β-unsaturated thiocarbonyl (PUSTC) scaffold, similar to the β-phenyl-α,β-unsaturated carbonyl (PUSC) scaffold, acts as a core inhibitory structure for tyrosinase, twelve (Z)-5-(substituted benzylidene)-4-thioxothiazolidin-2-one ((Z)-BTTZ) derivatives were designed and synthesized. Seven of the twelve derivatives showed stronger inhibitory activity than kojic acid against mushroom tyrosinase. Compound 2b (IC50 = 0.47 ± 0.97 µM) exerted a 141-fold higher inhibitory potency than kojic acid. Kinetic studies’ results confirmed that compounds 2b and 2f are competitive tyrosinase inhibitors, which was supported by high binding affinities with the active site of tyrosinase by docking simulation. Docking results using a human tyrosinase homology model indicated that 2b and 2f might potently inhibit human tyrosinase. In vitro assays of 2b and 2f were conducted using B16F10 melanoma cells. Compounds 2b and 2f significantly and concentration-dependently inhibited intracellular melanin contents, and the anti-melanogenic effects of 2b at 10 µM and 2f at 25 µM were considerably greater than the inhibitory effect of kojic acid at 25 µM. Compounds 2b and 2f similarly inhibited cellular tyrosinase activity and melanin contents, indicating that the anti-melanogenic effects of both were due to tyrosinase inhibition. A strong binding affinity with the active site of tyrosinase and potent inhibitions of mushroom tyrosinase, cellular tyrosinase activity, and melanin generation in B16F10 cells indicates the PUSTC scaffold offers an attractive platform for the development of novel tyrosinase inhibitors.

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The Antiviral and Antimalarial Drug Repurposing in Quest of Chemotherapeutics to Combat COVID-19 Utilizing Structure-Based Molecular Docking

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323999200824115536 ◽

2020 ◽

Vol 23 ◽

Author(s):

Sisir Nandi ◽

Mohit Kumar ◽

Mridula Saxena ◽

Anil Kumar Saxena

Keyword(s):

Molecular Docking ◽

In Silico ◽

Drug Repurposing ◽

Clinical Settings ◽

The Novel ◽

In Silico Docking ◽

Biochemical Mechanisms ◽

Novel Coronavirus ◽

In Silico Molecular Docking

Background: The novel coronavirus disease (COVID-19) is caused by a new strain (SARS-CoV-2) erupted in 2019. Nowadays, it is a great threat that claims uncountable lives worldwide. There is no specific chemotherapeutics developed yet to combat COVID-19. Therefore, scientists have been devoted in the quest of the medicine that can cure COVID- 19. Objective: Existing antivirals such as ASC09/ritonavir, lopinavir/ritonavir with or without umifenovir in combination with antimalarial chloroquine or hydroxychloroquine have been repurposed to fight the current coronavirus epidemic. But exact biochemical mechanisms of these drugs towards COVID-19 have not been discovered to date. Method: In-silico molecular docking can predict the mode of binding to sort out the existing chemotherapeutics having a potential affinity towards inhibition of the COVID-19 target. An attempt has been made in the present work to carry out docking analyses of 34 drugs including antivirals and antimalarials to explain explicitly the mode of interactions of these ligands towards the COVID-19protease target. Results: 13 compounds having good binding affinity have been predicted towards protease binding inhibition of COVID-19. Conclusion: Our in silico docking results have been confirmed by current reports from clinical settings through the citation of suitable experimental in vitro data available in the published literature.

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In Silico Appraisal, Synthesis, Antibacterial Screening and DNA Cleavage for 1,2,5-thiadiazole Derivative

Current Computer - Aided Drug Design ◽

10.2174/1573409915666190206142756 ◽

2019 ◽

Vol 15 (5) ◽

pp. 445-455 ◽

Cited By ~ 6

Author(s):

Suraj N. Mali ◽

Sudhir Sawant ◽

Hemchandra K. Chaudhari ◽

Mustapha C. Mandewale

Keyword(s):

Molecular Docking ◽

Dna Cleavage ◽

In Silico ◽

Oral Absorption ◽

Inhibition Mechanism ◽

Hydrogen Binding ◽

Docking Score ◽

Antibacterial Screening ◽

Mycobacteria Tuberculosis

Background: : Thiadiazole not only acts as “hydrogen binding domain” and “two-electron donor system” but also as constrained pharmacophore. Methods:: The maleate salt of 2-((2-hydroxy-3-((4-morpholino-1, 2,5-thiadiazol-3-yl) oxy) propyl) amino)- 2-methylpropan-1-ol (TML-Hydroxy)(4) has been synthesized. This methodology involves preparation of 4-morpholino-1, 2,5-thiadiazol-3-ol by hydroxylation of 4-(4-chloro-1, 2,5-thiadiazol-3-yl) morpholine followed by condensation with 2-(chloromethyl) oxirane to afford 4-(4-(oxiran-2-ylmethoxy)-1,2,5-thiadiazol- 3-yl) morpholine. Oxirane ring of this compound was opened by treating with 2-amino-2-methyl propan-1- ol to afford the target compound TML-Hydroxy. Structures of the synthesized compounds have been elucidated by NMR, MASS, FTIR spectroscopy. Results: : The DSC study clearly showed that the compound 4-maleate salt is crystalline in nature. In vitro antibacterial inhibition and little potential for DNA cleavage of the compound 4 were explored. We extended our study to explore the inhibition mechanism by conducting molecular docking, ADMET and molecular dynamics analysis by using Schrödinger. The molecular docking for compound 4 showed better interactions with target 3IVX with docking score of -8.508 kcal/mol with respect to standard ciprofloxacin (docking score= -3.879 kcal/mol). TML-Hydroxy was obtained in silico as non-carcinogenic and non-AMES toxic with good percent human oral absorption profile (69.639%). TML-Hydroxy showed the moderate inhibition against Mycobacteria tuberculosis with MIC 25.00 μg/mL as well as moderate inhibition against S. aureus, Bacillus sps, K. Pneumoniae and E. coli species. Conclusion: : In view of the importance of the 1,2,5-thiadiazole moiety involved, this study would pave the way for future development of more effective analogs for applications in medicinal field.

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Chemical Derivatization and Characterization of Novel Antitrypanosomals for African Trypanosomiasis

Molecules ◽

10.3390/molecules26154488 ◽

2021 ◽

Vol 26 (15) ◽

pp. 4488

Author(s):

Aboagye Kwarteng Dofuor ◽

Temitayo Samson Ademolue ◽

Cynthia Mmalebna Amisigo ◽

Kwaku Kyeremeh ◽

Theresa Manful Gwira

Keyword(s):

Structural Modification ◽

Spectroscopic Analysis ◽

Microscopic Analysis ◽

The Novel ◽

Chemical Derivatization ◽

African Trypanosomiasis ◽

Chemical Structures ◽

Normal Ratio

The search for novel antitrypanosomals and the investigation into their mode of action remain crucial due to the toxicity and resistance of commercially available antitrypanosomal drugs. In this study, two novel antitrypanosomals, tortodofuordioxamide (compound 2) and tortodofuorpyramide (compound 3), were chemically derived from the natural N-alkylamide tortozanthoxylamide (compound 1) through structural modification. The chemical structures of these compounds were confirmed through spectrometric and spectroscopic analysis, and their in vitro efficacy and possible mechanisms of action were, subsequently, investigated in Trypanosoma brucei (T. brucei), one of the causative species of African trypanosomiasis (AT). The novel compounds 2 and 3 displayed significant antitrypanosomal potencies in terms of half-maximal effective concentrations (EC50) and selectivity indices (SI) (compound 1, EC50 = 7.3 μM, SI = 29.5; compound 2, EC50 = 3.2 μM, SI = 91.3; compound 3, EC50 = 4.5 μM, SI = 69.9). Microscopic analysis indicated that at the EC50 values, the compounds resulted in the coiling and clumping of parasite subpopulations without significantly affecting the normal ratio of nuclei to kinetoplasts. In contrast to the animal antitrypanosomal drug diminazene, compounds 1, 2 and 3 exhibited antioxidant absorbance properties comparable to the standard antioxidant Trolox (Trolox, 0.11 A; diminazene, 0.50 A; compound 1, 0.10 A; compound 2, 0.09 A; compound 3, 0.11 A). The analysis of growth kinetics suggested that the compounds exhibited a relatively gradual but consistent growth inhibition of T. brucei at different concentrations. The results suggest that further pharmacological optimization of compounds 2 and 3 may facilitate their development into novel AT chemotherapy.

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Determination of Chemical Composition, In Vitro and In Silico Evaluation of Essential Oil from Leaves of Apium graveolens Grown in Saudi Arabia

Molecules ◽

10.3390/molecules26237372 ◽

2021 ◽

Vol 26 (23) ◽

pp. 7372

Author(s):

Ahmed I. Foudah ◽

Mohammed H. Alqarni ◽

Aftab Alam ◽

Mohammad Ayman Salkini ◽

Pravej Alam ◽

...

Keyword(s):

Saudi Arabia ◽

Essential Oil ◽

In Silico ◽

Docking Simulation ◽

Antimicrobial Activities ◽

Apium Graveolens ◽

Gas Chromatography Mass Spectrometry ◽

Major Constituent ◽

Anti Inflammatory

The aim of this study was to explore the composition and evaluate the in silico and in vitro antioxidants and antimicrobial and anti-inflammatory effects of Apium graveolens var. dulce leaves essential oil (AGO) collected from Al-Kharj (Saudi Arabia). AGO was isolated using the hydro-distillation method, and its composition was studied using gas-chromatography-mass Spectrometry (GC–MS), antimicrobial activities using well diffusion assay, and antioxidant and anti-inflammatory activities using spectrophotometric methods. The pharmacological activities of their major compounds were predicted using PASS (prediction of activity spectra for substances) and drug-likening properties by ADME (absorption, distribution, metabolism, and excretion) through web-based online tools. Isocnidilide (40.1%) was identified as the major constituent of AGO along with β-Selinene, Senkyunolide A, Phytyl acetate, and 3-Butylphthalide. AGO exhibited a superior antibacterial activity, and the strongest activity was detected against Gram-positive bacteria and Candida albicans. Additionally, it exhibited a weaker antioxidant potential and stronger anti-inflammatory effects. PASS prediction supported the pharmacological finding, whereas ADMET revealed the safety of AGO. The molecular docking of isocnidilide was carried out for antibacterial (DNA gyrase), antioxidant (tyrosinase), and anti-inflammatory (cyclooxygenase-2) activities. The docking simulation results were involved hydrophilic interactions and demonstrated high binding affinity of isocnidilide for anti-inflammatory protein (cycloxygenase-2). The presence of isocnidilide makes AGO a potential anti-inflammatory and antimicrobial agent. AGO, and its major metabolite isocnidilide, may be a suitable candidate for the future drug development.

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ACTIVITY SCREENING AND STRUCTURE MODIFICATION OF ARTOCARPIN AGAINST ACE2 AND MAIN PROTEASE THROUGH IN SILICO METHOD

International Journal of Applied Pharmaceutics ◽

10.22159/ijap.2021v13i6.42571 ◽

2021 ◽

pp. 192-198

Author(s):

MUHAMMAD FAUZI ◽

ARIS FADILLAH ◽

FAUZI RAHMAN ◽

JUWITA RAMADHANI ◽

KARINA ERLIANTI ◽

...

Keyword(s):

Antiviral Activity ◽

In Silico ◽

Docking Simulation ◽

Positive Control ◽

Hydroxyl Group ◽

Artocarpus Altilis ◽

Main Protease ◽

Activity Screening ◽

The Stability ◽

The Right

Objective: SARS-CoV-2 is a type of coronavirus that causes COVID-19 disease. Currently, the right and effective drug for the treatment of COVID-19 has not been found. Artocarpin in the breadfruit plant (Artocarpus altilis), which was tested, has been shown to have antiviral activity. However, artocarpin has a hydroxyl group that can undergo oxidation within a certain time, thereby reducing the stability of the compound and non-specific antiviral activity. Methods: In this study, the structural modification of artocarpin was carried out to obtain compounds with anticoronavirus activity with good physicochemical properties. This research was conducted in silico, including molecular docking simulation, bioavailability prediction, and preADMET. Results: The top 20 modified compounds were selected from each target's top 3 compounds, which had better bond energies compared to the positive control. These 3 compounds have the potential to inhibit ACE2 and Mpro receptors and 1 compound are better at inhibiting both. Conclusion: From the results of the research conducted, we conclude that the 3 best compounds can be potential candidates that can be developed as COVID-19 therapy.

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Kaempferol-Mediated Sensitization Enhances Chemotherapeutic Efficacy of Sorafenib Against Hepatocellular Carcinoma: An In Silico and In Vitro Approach

Advanced Pharmaceutical Bulletin ◽

10.34172/apb.2020.058 ◽

2020 ◽

Vol 10 (3) ◽

pp. 472-476

Author(s):

Bhagyalakshmi Nair ◽

Ruby John Anto ◽

Sabitha M ◽

Lekshmi R. Nath

Keyword(s):

Hepatocellular Carcinoma ◽

Multidrug Resistance ◽

Liver Cancer ◽

In Silico ◽

Culture Media ◽

Positive Control ◽

Advanced Hepatocellular Carcinoma ◽

Discovery Studio ◽

Toxic Concentrations

Purpose : Sorafenib is the sole FDA approved drug conventionally used for the treatment of advanced hepatocellular carcinoma (HCC). Despite of the beneficial use of sorafenib in the treatment of HCC, multidrug resistance still remains a challenge. HCC is inherently known as chemotherapy resistant tumor due to P-glycoprotein (P-gp)-mediated multidrug resistance. Methods: We studied the interaction energy of kaempferol with human multidrug resistance protein-1 (RCSB PDB ID: 2CBZ) using in silico method with the help of BIOVIA Discovery Studio. HepG2 and N1S1 liver cancer cell lines were treated in suitable cell culture media to evaluate the efficacy of kaempferol in chemo-sensitizing liver cancer cells towards the effect of sorafenib. Cell viability study was performed by MTT assay. Results: In silico analysis of kaempferol showed best docking score of 23.14 with Human Multi Drug Resistant Protein-1 (RCSB PDB ID: 2CBZ) compared with positive control verapamil. In in-vitro condition, combination of sub-toxic concentrations of both kaempferol and sorafenib produced 50% cytotoxicity with concentration of 2.5 µM each which indicates that kaempferol has the ability to reverse the MDR by decreasing the over-expression of P-gp. Conclusion: Kaempferol is able to sensitize the HepG2 and N1S1 against the sub-toxic concentration of sorafenib. Hence, we consider that the efficacy of sorafenib chemotherapy can be enhanced by the significant approach of combining the sub-toxic concentrations of sorafenib with kaempferol. Thus, kaempferol can be used as a better candidate molecule along with sorafenib for enhancing its efficacy, if validated through preclinical studies.

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