Comparative Analysis of the Antioxidative and Hepatoprotective Activities of Dimethyl Diphenyl Bicarboxylate in Four Animal Models of Hepatic Injury

As a well-known hepatoprotective and antioxidant agent, dimethyl diphenyl bicarboxylate (DDB) has frequently been employed to remedy various liver diseases. However, it is still uncertain whether DDB exerts consistent hepatoprotective and antioxidative activities against varying degrees of hepatic damage. Therefore, DDB (100, 25, 5, or 50 mg/kg depending on the model) was administered to animals in four representative models of liver injury (CCl₄ chemical acute model, DMN subchronic model, TAA chronic model, and restraint stress psychological acute model). Horizontal comparative analysis indicated that DDB significantly lowered the excess serum AST and ALT levels in the CCl₄ and DMN models but not in the TAA and restraint stress models. In accordance with this result, DDB markedly reduced oxidative stress indices (hepatic MDA and ROS) but restored five main antioxidant components (GSH content, GSH-peroxidase, GSH-reductase, SOD, and catalase activity) in the CCl₄ and DMN models. DDB failed to normalize oxidative stressors in the restraint stress-induced injury model and restore these five antioxidant components in the TAA model. Overall, our results produced a comprehensive overview of the effects of DDB on oxidative stressors and the main antioxidative components using four animal models. These findings will provide valuable clues to guide therapeutic clinical applications.

Social behavior effects of diphenyl dimethyl bicarboxylate (DDB) in the sensory contact model

Sensory contact model (SCM) permits the evolution of diverse psychopathological states by the repeated antagonistic interactions between male mice. Biphenyl dimethyl dicarboxylate (DDB) is used as a hepatoprotective agent. The present work aimed to study the possible effects of DDB on social behavior developed by SCM by studying its effects on the transformation process to aggressive and submissive behaviors. Besides, measuring behavioral changes using the open field test (OFT) and the elevated plus maze test (EPM), neurochemical parameters [serotonin (5HT), norepqinephrine (NE), and dopamine(DA)], and immunological changes (total leucocyte count, differential leucocytic count, and evaluation of bone marrow lymphocytes count and viability assessment). Adult male Swiss mice were used; DDB was given in a dose of 100 mg/kg by oral gavage daily for 2 weeks from the fifth day to the last day of the SCM. The present study concluded that administration of DDB to the SCM involved animals was shown to be associated with significant positive impacts on the behavior of depressed partner in the SCM which were manifested by decreased latency and increased ambulation and rearing in OFT, increased number of entry in the open arm/total no of entries in EPM. This was associated with changes in brain levels of neurotransmitters which were manifested by increased NE and decreased DA, as well as the examined immunity related parameters which were manifested by increased total leucocyte count, bone marrow lymphocytes, and monocytes. So DDB can be used as a supportive antidepressant agent in patients with liver impairment and should be avoided in aggressive ones. However, more randomized controlled trials should be carried out to ascertain these effects.

Comparative study of the binding of Trypsin with bifendate and analogs by spectrofluorimetry

The interactions between Trypsin and bifendate (DDB) or analogs (I, II and III) were investigated by fluorescence, UV-visible absorption, resonance light scattering, synchronous fluorescence and 3D spectroscopy under mimic physiological conditions. The results revealed that DDB and analogs caused the fluorescence quenching of Trypsin by the formation of DDB/I/II/III-Trypsin complex. The quenching and energy transfer mechanisms were discussed. The binding constants and thermodynamic parameters at three different temperatures were obtained. The hydrophobic interaction was the predominant intermolecular forces to stabilize the complex. Results showed that DDB was the stronger quencher and bound to Trypsin with higher affinity than other three analogs.

Dimethyl dimethoxy biphenyl dicarboxylate attenuates hepatic and metabolic alterations in high fructose-fed rats

High fructose consumption is currently linked to metabolic disorders including insulin resistance and dyslipidemia as well as hepatic steatosis. Dimethyl dimethoxy biphenyl dicarboxylate (DDB) is a hepatoprotectant with antioxidant and anti-inflammatory properties. The aim of this study therefore is to evaluate the effect of DDB on high fructose-induced metabolic disturbances and hepatic steatosis in a rat model. Male Wistar rats were allocated into three groups: control, fructose-fed (10% in drinking water and 10% in diet), and fructose-fed DDB (300 mg/kg, orally)-treated groups. Rats were fed a high-fructose diet for 6 weeks, while DDB was administered for an additional 2 weeks. High-fructose consumption elevated serum glucose and insulin levels and impaired oral glucose tolerance test, revealing insulin resistance. It also increased serum triglycerides and alanine aminotransferase as well as visceral fat content and decreased serum high-density lipoprotein. Additionally, histopathological examination revealed that high fructose intake induced hepatic steatosis. These alterations were associated with increased serum uric acid as well as hepatic content of malondialdehyde and nitric oxide (NO) in addition to overexpression of inducible NO synthase (iNOS). DDB administration significantly ameliorated the high fructose-induced hepatic and metabolic alterations. In conclusion, DDB ameliorates high fructose-induced metabolic disorders and hepatic steatosis in rats. Such protection is, at least in part, due to the inhibition of lipid peroxidation, decrease in iNOS overexpression, and reduction of elevated uric acid.