Anti-inflammatory activity of 2-acyl-5(3)-hydroxytetrahydro-1H-pyrazole derivatives

Qualitative and quantitative analyses of chemical constituents in vitro and in vivo and systematic evaluation of the pharmacological effects of Tibetan medicine Zhixue Zhentong capsules

Introduction: Zhixue Zhentong capsules (ZXZTCs) are a Tibetan medicine preparation solely composed of Lamiophlomis rotata (Benth.) Kudo. L. rotata is the only species of the genus Laniophlomis (family Lamiaceae) that has medicinal constituents derived from the grass or root and rhizome. L. rotata is one of the most extensively used folk medicines by Tibetan, Mongolian, Naxi, and other ethnic groups in China and has been listed as a first-class endangered Tibetan medicine. The biological effects of the plant include hemostasis, analgesia, and the removal of blood stasis and swelling. Purpose: This study aimed to profile the overall metabolites of ZXZTCs and those entering the blood. Moreover, the contents of six metabolites were measured and the hemostatic, analgesic, and anti-inflammatory effects of ZXZTCs were explored. Methods: Ultra-performance liquid chromatography-tandem quadrupole time-of-flight high-resolution mass spectrometry (UPLC-Q-TOF-MS) was employed for qualitative analysis of the metabolites of ZXZTCs and those entering the blood. Six metabolites of ZXZTCs were quantitatively determined via high-performance liquid chromatography The hemostatic, analgesic, and anti-inflammatory effects of ZXZTCs were evaluated in various animal models. Results: A total of 36 metabolites of ZXZTCs were identified, including 13 iridoid glycosides, 9 flavonoids, 9 phenylethanol glycosides, 4 phenylpropanoids, and 1 other metabolite. Overall, 11 metabolites of ZXZTCs entered the blood of normal rats. Quantitative analysis of the six main metabolites, shanzhiside methyl ester, chlorogenic acid, 8-O-acetyl shanzhiside methyl ester, forsythin B, luteoloside, and verbascoside, was extensively performed. ZXZTCs exerted hemostatic effects by reducing platelet aggregation and thrombosis and shortening bleeding time. Additionally, ZXZTCs clearly had an analgesic effect, as observed through the prolongation of the latency of writhing, reduction in writhing, and increase in the pain threshold of experimental rats. Furthermore, significant anti-inflammatory effects of ZXZTCs were observed, including a reduction in capillary permeability, the inhibition of foot swelling, and a reduction in the proliferation of granulation tissue. Conclusion: Speculative identification of the overall metabolites of ZXZTCs and those entering the blood can provide a foundation for determining its biologically active constituents. The established method is simple and reproducible and can help improve the quality control level of ZXZTCs as a medicinal product. Evaluating the hemostatic, analgesic, and anti-inflammatory activities of ZXZTCs can help reveal its mechanism.

Pyrazoles and Pyrazolines as Anti-Inflammatory Agents

The five-membered heterocyclic group of pyrazoles/pyrazolines plays important role in drug discovery. Pyrazoles and pyrazolines present a wide range of biological activities. The synthesis of the pyrazolines and pyrazole derivatives was accomplished via the condensation of the appropriate substituted aldehydes and acetophenones, suitable chalcones and hydrazine hydrate in absolute ethanol in the presence of drops of glacial acetic acid. The compounds are obtained in good yields 68-99% and their structure was confirmed using IR, ¹H-NMR, ¹³C-NMR and elemental analysis. The novel derivatives were studied in vitro for their antioxidant, anti-lipid peroxidation (AAPH) activities and inhibitory activity of lipoxygenase. Both classes strongly inhibit lipid peroxidation. Compound 2g was the most potent lipoxygenase inhibitor (IC₅₀ = 80 µM). The inhibition of the carrageenin-induced paw edema (CPE) and nociception was also determined, with compounds 2d and 2e being the most potent. Compound 2e inhibited nociception higher than 2d. Pyrazoline 2d was found to be active in a preliminary test, for the investigation of anti-adjuvant-induced disease (AID) activity. Pyrazoline derivatives were found to be more potent than pyrazoles. Docking studies of the most potent LOX inhibitor 2g highlight hydrophobic interactions with VAL126, PHE143, VAL520 and LYS526 and a halogen bond between the chlorine atom and ARG182.