Histo-morphological assessment of the oral effect of gadolinium nanocomposite on kidneys and liver of white rats

Abstract

Introduction. The prospect of using gadolinium nanoparticles to achieve high-contrast images when performing MRI with a significantly lower amount of the injected substance dictates the need for its comprehensive study. The high efficiency of nanoparticles can be achieved only due to an effective nanostabilizing matrix, a high–molecular compound of arabinogalactan isolated from Siberian larch wood. Materials and methods. Gadolinium nanocomposite encapsulated in a natural polymer matrix of arabinogalactan was administered per os for 10 days to adult mature male white rats (seventy two individuals) at a dose of 500 µg/kg body weight and 5000 µg/kg body weight, respectively. The examination took place in 2 stages – immediately after the end of the seed (early period) and 6 months after the end of exposure (remote period). A set of methods was used to assess the structural and functional state of the kidneys and liver, as well as determine the concentration of gadolinium in the above-mentioned organs.Results. The structural and functional features of the gadolinium nanocomposite effect on kidney tissue were expressed in a change in the area of the Shumlyansky–Bowman capsule, both in the early and in the long-term post-exposure period, however, these changes fit into the parameters of the physiological norm for this organ, while it was proved that the nanocomposite is able to penetrate into the liver and kidney tissue, remaining there in the remote post-contact period.Limitations. The use of one type of animal, a limited number of techniques used.Conclusion. The gadolinium nanoparticles, due to their specified physico-chemical characteristics and the almost complete absence of toxicity to target organs (kidneys, liver), are promising therapeutic and diagnostic drugs, which can later be used to create new-generation diagnostic drugs.Compliance with ethical standards. The work was carried out in accordance with the protocol of experimental research, the principles set out in the European Convention for the Protection of Vertebrate Animals Used for Experiments or Other Scientific Purposes ETS No. 123, GOST 33215–2014 “Guidelines for the care and care of laboratory animals. Rules of equipment of premises and organization of procedures”, Recommendations for euthanasia of experimental animals: Part 1, Part 2. Permission was obtained from the Local Ethics Committee to conduct research (Protocol No. 8 dated 12/15/2023).Contribution: Novikov M.A. – concept and design of research, data processing, editing, writing; Titov E.A. – concept and design of research editing; Pankova A.A. – collection of material and data processing; Lisetskaya L.G. – sample preparation of materials for concentration determination, recalculation of primary quantitative data; Sosedova L.M. – concept and research design, editing, and writing. All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.Using AI. To search for additional sources of literature, DeepSeek V4 artificial intelligence-based software was used (date of use – 03/19/2026).Conflict of interest. The authors declare no conflict of interest.Funding. The study was carried out within the framework of the state assignment of the East Siberian Institute of Medical and Environmental Research.Received: April 13, 2026 / Accepted: July 1, 2026 / Published: October 20, 2026