Potential effect of new (E)-4-hydroxy -N'-(1-(7-hydroxy-2-oxo-2H-chromen-3-yl) ethylidene) benzohydrazide against acute myocardial infarction: Haemodynamic, biochemical and histological studies.

This study aimed to explore the cardioprotective effect of new synthesized coumarin (E)-4-hydroxy-N'-(1-(7-hydroxy-2-oxo-2H-chromen-3-yl) ethylidene) benzohydrazide denoted (Hyd.Cou) against myocardial infarction disorders. Male Wistar rats were divided into four groups; Control, isoproterenol (ISO), ISO + Acenocoumarol (Ac) and ISO + Hyd.Cou. Results showed that the ISO group exhibited serious alteration in EGC pattern, significant heart hypertrophy (+33%), haemodynamic disturbance and increase in plasma rate of CK-MB, LDH and troponin-T by 44, 53, and 170%, respectively, as compared to Control. Moreover, isoproterenol induced a rise in plasma angiotensin-converting enzyme activity (ACE) by 49%, dyslipidaemia, and increased thiobarbituric acid-reactive substances (TBARS) by 117% associated with decrease in the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx) by 46% and 58%, respectively in myocardium. Interestingly, the molecular docking calculation demonstrated strong interactions of Hyd.Cou with the receptors of the protein disulphide isomerase (PDI) which could highlight the antithrombotic effect. Moreover, Hyd.Cou improved plasma cardiac dysfunction biomarkers, mitigated the ventricle remodelling process and alleviated heart oxidative stress damage. Overall, Hyd.Cou prevented the heart from the remodelling process through inhibition of ACE activity and oxidative stress improvement.

Photocatalytic degradation of ibuprofen using titanium oxide: insights into the mechanism and preferential attack of radicals.

The present work studied ibuprofen degradation using titanium dioxide as a photocatalyst. Mechanistic aspects were presented and the preferred attack sites by the OH˙ radical on the ibuprofen molecule were detailed, based on experimental and simple theoretical-computational results. Although some previous studies show mechanistic proposals, some aspects still need to be investigated, such as the participation of 4-isobutylacetophenone in the ibuprofen degradation and the preferred regions of attack by OH˙ radicals. The photodegradation was satisfactory using 0.03 g of TiO2 and pH = 5.0, reaching 100% decontamination in 5 min. The zeta potential curve showed the regions of attraction and repulsion between TiO2 and ibuprofen, depending on the pH range and charge of the species, influencing the amount of by-products formed. Different by-products have been identified by GC-MS, such as 4-isobutylacetophenone. Ibuprofen conversion to 4-isobutylacetophenone takes place through decarboxylation reaction followed by oxidation. The proposed mechanism indicates that the degradation of ibuprofen undergoes a series of elementary reactions in solution and on the surface. Three different radicals (OH˙, O2 -˙ and OOH˙) are produced in the reaction sequence and contribute strongly to the oxidation and mineralization of ibuprofen and by-products, but the hydroxyl radical has a greater oxidation capacity. The simple study using the DFT approach demonstrated that the OH˙ radical attacks preferentially in the region of the ibuprofen molecule with high electronic density, which is located close to the aromatic ring (C[double bond, length as m-dash]C bond). The presence of the OH˙ radical was confirmed through a model reaction using salicylic acid as a probe molecule.