Bamal, H.-D. | bioRxiv Science

bioRxiv2024

Anti-inflammatory assessment of zinc oxide nanoparticles mediated Aframomum citratum (C. Pereira) K. Schum (Zingiberaceae) in Wistar rats

IntroductionZinc oxide nanoparticles (ZnONPs) have been synthesized using a wide range of techniques, including green chemistry, because of their versatility, cost effectiveness, and environmentally friendly nature, offering thereby interesting and inexpensive therapeutic options. This study aimed to develop zinc oxide nanoparticles as an anti-inflammatory agent using Aframomum citratum seed extract. MethodologyZnONPs were prepared by the reaction between zinc nitrate and an alkalineaqueous extract of A. citratum seeds. The isolated nanoparticles were then characterized using UV-Vis, FTIR, SEM/EDX, PXRD and TEM techniques. The toxicological profile was assessed at a limited dose of 2000 mg/kg in rats, and methods for heat denaturation of egg albumin, stabilization of red blood cell membranes and inhibition of carrageenan-induced plantar oedema were studied to assess anti-inflammatory properties. ResultsThe formation of ZnONPs was observed by a color change and the appearance of the plasmon resonance peak at 360 nm in the UV-Vis spectrum while FTIR confirmed the presence of secondary metabolites; SEM confirmed the presence of multiform aggregates, and TEM visualize point like particles. EDS confirmed the presence of Zn atoms within the synthetized material. The toxicological profile studied showed no harmful signs; zinc oxide nanoparticles synthesized from A. citratum seed extract showed high inhibition percentages of 86 (1mg/mL); 77 (0.6mg/mL) and 79(1mg/mL) when subjected to inhibition of heat-induced egg albumin denaturation, red cell membrane stabilization and oedema induction by carrageenan respectively, not significatively different compared with diclofenac sodium as positive controls. ConclusionZinc oxide nanoparticles synthesized and characterized from A. citratum seed extract act as a potent anti-inflammatory agent and are devoid of acute oral toxicity.

pharmacology and toxicology↗

bioRxiv2024

Chitosan nanocapsules with Alstonia boonei extract modulate the immune system in Wistar rats

The development of biosynthetic methods for nanoparticles using plants presents an exciting opportunity to better utilize our rich and diverse medicinal flora. We are particularly interested in creating nanocapsules using Alstonia boonei, a Cameroonian plant known for its immunomodulatory properties. Chitosan nanocapsules were synthesized from the methanol/dichloromethane extract of the powdered stem bark of A. boonei after harvest and drying. The encapsulation of the secondary metabolites was achieved using the ionic gelation method, which involved the agitation of a chitosan solution, extract, and tripolyphosphate. Subsequently, the encapsulation efficiency was calculated. Infrared spectroscopy identified the various functional groups present in the nanocapsules. The acute toxicological profile of these chitosan nanocapsules at a limit dose of 2000 mg/kg, along with their immunomodulatory activities, was evaluated in Wistar rats. The immunomodulatory potential was assessed in dexamethasone-induced immunosuppressed rats by measuring total blood count, delayed-type hypersensitivity response, and hemagglutinating antibody titre between groups of animals after 14 days of treatment. The data collected on the synthesis and characterization confirmed the formation of nanocapsules. This was evidenced by infrared spectroscopy and an entrapment efficiency of 69%. Powder X-ray diffraction confirmed the presence of chitosan in the polymer material. SEM imaging further confirmed the formation of nanocapsules. The toxicological profile of these nanocapsules was found to be satisfactory. Administration of chitosan nanocapsules containing Al. boonei methanol/dichloromethane extracts at doses of 100 mg/kg, 200 mg/kg, and 500 mg/kg body weight significantly prevented dexamethasone-induced immunosuppression in rats. This was achieved by increasing the parameters of total blood count (hematocrit, mean corpuscular volume, platelets, lymphocytes, and granulocyte counts), hemagglutinating antibody titre values, and delayed type hypersensitivity response induced by chicken red blood cells. However, doses of 500 mg/kg of crude A. boonei extract and 500 mg/kg body weight of empty chitosan nanocapsules did not show this effect. The nanocapsules generated from the extracts of chitosan and A. boonei are responsible for immunostimulatory activity and possess therapeutic potentials for the prevention of depressed immune depressed conditions with satisfactory safety at acute dose.

pharmacology and toxicology↗