In vivo anti-nociceptive potential and cyclooxygenases 1 and 2 selectivity of di-naphthodiospyrols from Diospyros lotus

Density functional theory, molecular docking and in vivo muscle relaxant, sedative, and analgesic studies of indanone derivatives isolated from Heterophragma adenophyllum

Heterophragma adenophyllum (HA) is an important medicinal plant which is used in traditional medicine for the treatment of muscular tension and pain. Herein, we report the isolation of methyl,1,2-dihydroxy-2-(3-methylbut-2-en-1-yl)-3-oxo-2,3-dihydro-1H-indene-1-carboxylate (1), from the roots of H. adenophyllum. The isolated compound 1 was evaluated for in vivo muscle relaxant, sedative, and analgesic potential in Swiss albino mice. Results revealed that the isolated compound 1 exhibited a dose- and time-dependent muscle coordination (51%) and a significant (p < 01) sedative effect. It also showed a considerable (p < 0.5) analgesia after 30 min of post treatment and was maintained for up-to 120 min of experimental duration. In acute toxicity studies, no mortality was observed which indicates a preliminary safety of compound 1. Furthermore, the experimental results were compared with the theoretical studies by using density functional theory (DFT). The stability of the compound as well as the flow of electrons was determined by the calculated Frontier orbital analysis. The calculated stretching frequencies, ¹H-NMR/¹³C-NMR chemical shift values and UV-visible spectra were found to be in agreement with experimental values. The results obtained from molecular docking studies were used to explore the mechanism of analgesic and muscle relaxant activity.Communicated by Ramaswamy H. Sarma.

In vivo analgesic, anti-inflammatory, and sedative activity and a molecular docking study of dinaphthodiospyrol G isolated from Diospyros lotus

BACKGROUND

Analgesic, anti-inflammatory, and sedative drugs are available with potential side effects such as peptic ulcer and addiction among other things. In this regard, research is underway to find safe, effective, and economical drugs free of these side effects. In this study, an isolated natural product from Diospyros lotus, was tested for the aforementioned bioactivities.

OBJECTIVES

To evaluate analgesic, anti-inflammatory, and sedative potential of D. lotus extracts in animal paradigms using BALB/c mice as experimental model.

METHODS

Analgesic, anti-inflammatory and sedative activities of dinaphthodiospyrol G (1) isolated from the chloroform fraction of D. lotus were evaluated using different experimental procedures. Anti-inflammatory effect was evaluated using the carrageenan and histamine-induced paw edema, whereas the antinociceptive effect was quantified by means of the hot plate analgesiometer. On the other hand, the sedative effect was determined using animal assay for screening the locomotors effects of compound 1. Compound 1 was also subjected to molecular modeling studies against cyclooxygenase enzymes.

RESULTS

Results from this investigation showed that the extract is devoid of anti-inflammatory and antinociceptive potentials but has a significant sedative effect, whereas the tested compound exhibited 55.23 and 78.34% attenuation in paw edema by carrageenan and histamine assays, respectively. A significant (p < 0.001) and dose-dependent antinociceptive and sedative effects were demonstrated by the isolated compound. Molecular docking and dynamics simulation studies of the isolated compound against cyclooxygenase enzyme indicated that compound 1 forms specific interactions with key residues in the active site of the target receptor, which validates the potential use of the isolated compound as cyclooxygenase inhibitor.

CONCLUSIONS

Compound 1 exhibited remarkable analgesic, anti-inflammatory, and sedative activities. These findings strongly justify the traditional use of D. lotus in the treatment of inflammation, pain, and insomnia.