Application of Elements of Quality by Design to Development and Optimization of HPLC Method for Fingolimod

Purpose: A HPLC method for Fingolimod was developed using a Quality by Design concept. QbD has gained importance in recent times due to regulatory requirements. Actual study was started after determination of target profile and qualification of instrument. Methods: Separation was carried on a Grace C-8 column (4.6 x 250 mm, 5-μm particle size).The composition of mobile phase was methanol and 20 mM ammonium formate buffer of pH5.8 in gradient mode HPLC method development is affected by critical factors like pH, flow rate and mobile phase composition. Results: To study the effects of these three factors on USP tailing, Box Behnken optimization model was applied. Desirability of the model was set at Tailing less than 1.2.Analysis of results was done using surface diagrams. Verification of Software generated results was done by taking six replicates of the run. Thus developed and optimised method was Finally validated as per ICH guideline. Conclusion: A Quality by Design approach has been successfully utilised in method development of the Fingolimod in bulk. All key aspect of QbD were tried to be implemented in said study. Systematic approach was utilized for method development which includes beginning with determination of target profile characteristics, instrument qualification, risk assessment, design of experiment and validation. Three factors i.e. Ph, flow rate and methanol concentration were analysed for their effect on USP tailing as a responce. Interaction and quadratic effect of the factors were studied with least possible runs by using Box Behnken model. Response surface diagrams and contour plots were studied for coming to conclusion which factors are affecting response and their limits were recorded. Optimum run condition was obtained; Replicates of run having optimized condition were taken to confirm the predicted response with actual response

Lipid-Coated Nanocrystals as a Tool for Improving the Antioxidant Activity of Resveratrol

Trans-resveratrol, a polyphenolic phytoalexin found in various plant sources, has been the focus of increasing attention in recent years because of its role in the prevention of many human diseases, and particularly because of its antioxidant properties. However, the in vivo effect of trans-resveratrol after oral administration is negligible when compared to its efficacy in vitro, due to its low bioavailability. Moreover, it presents stability issues as it is an extremely photosensitive compound when exposed to light. This work aims to develop lipid-coated nanocrystals in order to improve the antioxidant activity and bioavailability of trans-resveratrol. Lipid-coated trans-resveratrol nanocrystals with sizes lower than 500 nm, spherical shapes and smooth surfaces were obtained via a milling method. They showed a faster dissolution rate than the coarse trans-resveratrol powder. The antioxidant properties of trans-resveratrol were not impaired by the milling process. The in vivo pharmacokinetics of lipid-coated trans-resveratrol nanocrystals were evaluated after oral administration to rats, with a commercial Phytosome® formulation being used for comparison purposes. An increase in the trans-resveratrol area under the curve was observed and the lipid-coated nanocrystal formulation led to an enhancement in the oral bioavailability of the compound

Anxiolytic-<i>like</i> Effects by <i>trans</i>-Ferulic Acid Possibly Occur through GABAergic Interaction Pathways

Numerous previous studies reported that ferulic acid exerts anxiolytic activity. However, the mechanisms have yet to be elucidated. The current study aimed to investigate the anxiolytic effect of trans-ferulic acid (TFA), a stereoisomer of ferulic acid, and evaluated its underlying mechanism using in vivo and computational studies. For this, different experimental doses of TFA (25, 50, and 75 mg/kg) were administered orally to Swiss albino mice, and various behavioral methods of open field, hole board, swing box, and light–dark tests were carried out. Diazepam (DZP), a positive allosteric modulator of the GABAA receptor, was employed as a positive control at a dose of 2 mg/kg, and distilled water served as a vehicle. Additionally, molecular docking was performed to estimate the binding affinities of the TFA and DZP toward the GABAA receptor subunits of α2 and α3, which are associated with the anxiolytic effect; visualizations of the ligand-receptor interaction were carried out using various computational tools. Our findings indicate that TFA dose-dependently reduces the locomotor activity of the animals in comparison with the controls, calming their behaviors. In addition, TFA exerted the highest binding affinity (−5.8 kcal/mol) to the α2 subunit of the GABAA receptor by forming several hydrogen and hydrophobic bonds. Taken together, our findings suggest that TFA exerts a similar effect to DZP, and the compound exerts moderate anxiolytic activity through the GABAergic interaction pathway. We suggest further clinical studies to develop TFA as a reliable anxiolytic agent

Antiemetic activity of abietic acid possibly through the 5HT3 and muscarinic receptors interaction pathways

Abstract The present study was designed to evaluate the antiemetic activity of abietic acid (AA) using in vivo and in silico studies. To assess the effect, doses of 50 mg/kg b.w. copper sulfate (CuSO4⋅5H2O) were given orally to 2-day-old chicks. The test compound (AA) was given orally at two doses of 20 and 40 mg/kg b.w. On the other hand, aprepitant (16 mg/kg), domperidone (6 mg/kg), diphenhydramine (10 mg/kg), hyoscine (21 mg/kg), and ondansetron (5 mg/kg) were administered orally as positive controls (PCs). The vehicle was used as a control group. Combination therapies with the referral drugs were also given to three separate groups of animals to see the synergistic and antagonizing activity of the test compound. Molecular docking and visualization of ligand-receptor interaction were performed using different computational tools against various emesis-inducing receptors (D2, D3, 5HT3, H1, and M1–M5). Furthermore, the pharmacokinetics and toxicity properties of the selected ligands were predicted by using the SwissADME and Protox-II online servers. Findings indicated that AA dose-dependently enhances the latency of emetic retching and reduces the number of retching compared to the vehicle group. Among the different treatments, animals treated with AA (40 mg/kg) exhibited the highest latency (98 ± 2.44 s) and reduced the number of retching (11.66 ± 2.52 times) compared to the control groups. Additionally, the molecular docking study indicated that AA exhibits the highest binding affinity (− 10.2 kcal/mol) toward the M4 receptors and an elevated binding affinity toward the receptors 5HT3 (− 8.1 kcal/mol), M1 (− 7.7 kcal/mol), M2 (− 8.7 kcal/mol), and H1 (− 8.5 kcal/mol) than the referral ligands. Taken together, our study suggests that AA has potent antiemetic effects by interacting with the 5TH3 and muscarinic receptor interaction pathways. However, additional extensive pre-clinical and clinical studies are required to evaluate the efficacy and toxicity of AA

Possible hemoglobin enhancing effect of phytol in methotrexate-induced folate deficient Swiss albino mice: In vivo and in silico studies

The diterpenoid phytol is evidently acting against anemia in experimental animals. However, the molecular mechanisms behind this issue are yet to be discovered. This study aimed to evaluate phytol's effect on methotrexate-induced folate-deficient animals through in vivo and in silico studies. For this, a total of thirty adult male Swiss albino mice were randomly divided into six different groups, namely the normal control (vehicle), the negative control (folate deficiency inducer, methotrexate 3 ​mg/kg), the standard (folic acid 1.5 ​mg/kg), two test groups comprising phytol 25 and 50 ​mg/kg, and a combined group composed of the standard and highest test doses of phytol. Except for the vehicle, all groups were treated with methotrexate for the first 3 days (once/day) to induce folate deficiency. Then followed by the respective treatment once a day for 3 days. Hemoglobin (Hb) level was measured from the peripheral blood (by tail cutting) on days 1st (before treatment), 4th (after methotrexate treatment), and 7th (after treatment). On the other hand, the computational studies were performed by PyMol, PyRex, Discovery Studio, and other complementary tools. Findings suggest that phytol significantly (p ​< ​0.05) augmented Hb levels that are altered by methotrexate-induced reduction of Hb levels in animals dose-dependently. The combination also augmented Hb levels in animals; however, its effect was slightly lower than the individual groups (standard and test). In the in silico study, phytol showed good binding capacity (binding energy: −7.0 ​kcal/mol) with dihydrofolate reductase (DHFR). In conclusion, phytol may act against folate deficiency by altering methotrexate's impacts in animals, possibly through interacting with DHFR. Further validated research is necessary to develop phytol as an anti-anemia drug in the near future

Exploring antibiofilm potential of some new imidazole analogs against <i>C. albicans:</i> synthesis, antifungal activity, molecular docking and molecular dynamics studies

A series of 1, 2, 4, 5-tetrasubstituted imidazole derivatives were synthesized and their antibiofilm potential against Candida albicans was evaluated in vitro. Two of the synthesized derivatives 5e (IC50 = 25 µg/mL) and 5m (IC50 = 6 µg/mL),displayed better antifungal and antibiofilm potential than the standard drug Fluconazole (IC50 = 40 µg/mL) against C. albicans. Based on the in vitro results, we escalated the real time polymerase chain reaction (RT-PCR) analysis to gain knowledge of the enzymes expressed in the generation and maintenance of biofilms and the mechanism of biofilm inhibition by the synthesized analogues. We then investigated the possible interactions of the synthesized compounds in inhibiting agglutinin-like proteins, namely Als3, Als4 and Als6 were prominently down-regulated using in-silico molecular docking analysis against the previously available crystal structure of Als3 and constructed structure of Als4 and Als6 using the SWISS-MODEL server. The stability and energy of the agglutinin-like proteins–ligand complexes were evaluated using molecular dynamics simulations (MDS). According to the 100 ns MDS, all the compounds remained stable, formed a maximum of 3, and on average 2 hydrogen bonds, and Gibb’s free energy landscape analysis suggested greater affinity of the compounds 5e and 5m toward Als4 protein. Communicated by Ramaswamy H. Sarma</p