Cytoprotective effect of garlic alone versus co-administration of garlic and resveratrol in adriamycin-induced lung toxicity in albino rat: light microscopic, ultrastructural and immunohistochemical study

Adriamycin is a cytotoxic anthracycline antibiotic used to treat a wide variety of cancers. This study was made to detect the possible prophylactic effects of combining garlic and resveratrol in preventing adriamycin-induced pulmonary cytotoxicity. This study was conducted on a total number of 60 adult male albino rats. The rats were divided in an equally random manner into 6 groups: group I rats received nothing, group II received a dose of 50 mg/kg garlic extract orally for 3 weeks, group III received resveratrol in a dose of 20 mg/kg/day orally for 3 weeks, group IV rats were injected with 20 mg/kg adriamycin as a single dose via intraperitoneal route, group V received garlic extract for 3 weeks, then were injected with adriamycin in the same stated doses, and Group VI received garlic extract and resveratrol in same stated dose for 3 weeks, then were injected with adriamycin in the same stated dose. Lung specimens were processed for light microscopic, ultrastructural, and immunohistochemical studies. Adriamycin treatment caused histological alterations, thicker interstitial septa, extensive cellular infiltration, hypertrophied arterial wall, marked inducible Nitric Oxide Synthase immunoreaction, type I pneumocytes with destructed organelles as well as type II pneumocytes having large vacuoles. The combined garlic and resveratrol group demonstrated a considerable improvement in the changes to the histology and ultrastructure of adriamycin-induced lung injury. Combining garlic and resveratrol can prevent adriamycin-induced lung cytotoxicity in albino rats.

Thermodynamic and functional changes of alpha-chymotrypsin after interaction with gallic acid

In the present study, the interaction mechanism between gallic acid (GA) and α-Chymotrypsin (α-CT) was investigated by employing a series ofspectroscopic methods, computational docking and molecular dynamic (MD) simulation. Fluorescence spectra analysis indicated the formation of a stable complex between GA and α-CT, where the quenching of the fluorescence emission was predominantly characterized by a static mechanism. TheCA obtained binding constants for the α-CT-GA complex were in the order of 103 M-1, indicating the moderate binding affinity of GA for α-CT. The corresponding CD findings showed that the interaction between GA and α-CT resulted in an alteration of the protein's secondary structure. The findings of the enzyme activity investigation clearly showed that the presence of GA led to a notable decline in the enzymatic activity of α-CT, highlighting GA's function as an effective inhibitor for α-CT. The molecular docking simulations revealed the optimal binding site for the GA molecule within the α-CT structure and MD simulations confirmed the stability of the α-CT-GA complex. This research expands our comprehension regarding the behavior of enzymes in the presence of small-molecule ligands and opens avenues for food safety.

Analytical investigation of the influence of ornidazole on the native protein fluorescence

A novel spectrofluorimetric method for the determination of ornidazole (ORN) in pure form and dosage forms was developed based on the influence of ORN on the native fluorescence of bovine serum albumin (BSA) in a stimulated physiological environment. The obtained data reveal that the presence of ORN has a strong quenching effect on the fluorescence of BSA through both a dynamic and a static process. The parameters of the binding of ORN to BSA were calculated at different temperatures. Thermodynamic parameters values suggest a role of electrostatic and hydrophobic forces in the binding of ORN to BSA. The investigated method for the determination of ORN is accurate, precise and sensitive with a detection limit of 0.106 μg/mL and a quantification limit of 0.353 μg/mL. The quenching method was applied successfully in the determination of ORN in pure form and dosage forms.

Spectroscopic Studies on the Interaction between Tilorone and Human Serum Albumin

Under physiological conditions, in vitro interaction between the antiviral drug 2,7-bis[2-(diethylamino)ethoxy]-9-fluorenone dihydrochloride (Tilorone, TIL) and human serum albumin (HSA) was investigated at excitation wavelength 280 nm and at different temperatures (298 K and 313 K) by fluorescence emission spectroscopy. TIL showed a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constant is estimated as KA =7.19× 104L·mol-1 at 298 K. The enthalpy change (ΔHº) and entropy change (ΔSº) were derived to be negative values. A value of 1.63 nm for the average distance r between TIL (acceptor) and tryptophan residues of HSA (donor) was derived from the fluorescence resonance energy transfer.

Study on the interaction of 6-(2-morpholin-4-yl-ethyl)-6H-indolo [2,3-b]quinoxaline hydrochloride with human serum albumin by fluorescence spectroscopy

Under physiological conditions, in vitro interaction between the bio-active substance 6-(2-morpholin-4-yl-ethyl)-6H-indolo[2,3-b]quinoxaline hydrochloride (MIQ) and human serum albumin (HSA) was investigated at an excitation wavelength 260 nm and at different temperatures (298 K, 308 K and 313 K) by fluorescence emission spectroscopy. From spectral analysis, MIQ showed a strong ability to quench the intrinsic fluorescence of HSA through a static quenching procedure. The binding constant is estimated asK _A   =  2.55  ×  10^-4 l · mol^-1 at 298 K. Based on the thermodynamic parameters evaluated from the van 't Hoff equation, the enthalpy change (ΔH°) and entropy change (ΔS°) were derived to be negative values. A value of 2.37 nm for the average distance r between MIQ (acceptor) and tryptophan residues of HSA (donor) was derived from the fluorescence resonance energy transfer. UV/vis absorption spectra were used to confirm the quenching mechanism.

Inhibitory effects of ionic liquids on the lactic dehydrogenase activity

Ionic liquids (ILs) were widely used in scientific and industrial application and have been reported to possess potential toxicity to the environment and human health. The effects of six typical N-methylimidazolium-based ILs ([Cnmim]X, n=4, 6, 8; X=Br(-), Cl(-), BF4(-), CF3SO3(-)) on the lactic dehydrogenase (LDH) activity and the molecular interaction mechanism of ILs and the LDH were investigated with the aid of spectroscopic techniques. Experimental results showed that the LDH activity was inhibited in the presence of ILs. For the ILs with the same anion but different cations, their inhibitory ability on the LDH activity increased with increasing the alkyl chain length on the IL cation. Thermodynamic parameters, enthalpy change (ΔH) and entropy change (ΔS) were obtained by analyzing the fluorescence behavior of LDH with the addition of ILs. Both positive ΔH and ΔS suggested that hydrophobicity was the major driven force in the interaction process as expected.