Experimental assessment of endotoxicosis in cadmium exposure by the content of substances of low and medium molecular weight

Introduction. Anthropogenic activities and industrial production are the main source of pollutants of various classes. Among heavy metals, cadmium remains one of the most dangerous ecotoxicants capable of affecting metabolic processes and cell homeostasis.

The study aims to investigate the effect of subchronic cadmium intoxication on the metabolic processes of the body in terms of the content of low and medium molecular weight substances in the kidneys and blood plasma, as well as the adaptive capabilities of the body during the post-intoxication period.

Materials and methods. The experiment was performed on 60 male Wistar rats (220-250 g), divided into 6 groups. Subchronic intoxication was modeled by administration of cadmium acetate with drinking water at a dose of 1/50 LD₅₀ for 28 days. The rats were removed from the experiment under ether anesthesia by decapitation, the authors used plasma and renal homogenate for the study, and also determined the concentration of substances of low and medium molecular weight. The researchers performed statistical processing using the Kraskel-Wallis criterion, then they calculated the Mann-Whitney criterion (STATISTICA 13.0, p<0.05).

Results. During the 28 days of the experiment, the concentration of endotoxicosis markers increased in all the studied media. After the cessation of cadmium intake in all media, the authors observed a tendency to increase the concentration of substances of low and medium molecular weight, most pronounced in the kidneys.

Limitations. The study was conducted using laboratory animals of the same sex and age, which does not allow us to assess the toxicity of cadmium, taking into account these differences. To determine metabolic processes and their disorders, the authors used the endotoxicosis assessment method, which refers to conditionally specific methods of laboratory diagnosis of intoxication.

Conclusions. The results obtained indicate violations of metabolic processes, homeostatic mechanisms and the development of endotoxicosis under environmental stress, as well as insufficient restorative adaptive resources of the body, which raises the question of the need to develop corrective and preventive measures to neutralize the main damaging mechanisms of action of cadmium.

Ethics. Research involving laboratory animals was conducted in compliance with the European Convention for the Protection of Vertebrates Used for Experiments or Other Scientific Purposes (ETS N 123), Directive 2010/63/EC of the European Parliament and of the Council of the European Union of 22.09.2010 on the protection of animals used for scientific purposes. The study protocol was approved by the Ethics Committee of the Kursk State Medical University at the meeting of the Preclinical Research Section of the REC (Protocol No. 3 dated October 17, 2022).

Contributions:
Korolev V.A. — research concept and design, data analysis and interpretation;
Babkina L.A. — research concept and design, statistical processing, data analysis and interpretation;
Chertova R.Y. — literary search, data analysis and interpretation, writing and editing the text;
Sudakova Z.A. — participation in the research, processing of the material;
All co-authors — approving the final version of the article and ensuring the integrity of all parts of the article.

Funding. The study had no funding.

Conflict of interest. The authors declare no conflict of interest.

Received: 10.06.2026 / Accepted: 23.06.2026 / Published: 11.08.2026

1. Jan A.T., Azam M., Siddiqui K., Ali A., Choi I., Haq Q.M.R. Heavy metals and human health: mechanistic insight into toxicity and counter defense system of antioxidants. Int. J. Mol. Sci. 2015; 16(12): 29592–29630. https://doi.org/10.3390/ijms161226183

2. Peana M., Pelucelli A., Chasapis C.T., Perlepes S.P., Bekiari V., Medici S., et al. Biological effects of human exposure to environmental cadmium. Biomol. 2022; 13(1): 36. https://doi.org/10.3390/biom13010036

3. Korolev V.A., Babkina L.A., Fel`ker E.V., Usachev M.A., Chertova R.Yu., Artemova I.A. et al. Features of cadmium distribution in the body under conditions of subchronic intoxication. Gigiena i sanitariya. 2026; 105(3): 308–313. https://doi.org/10.47470/0016-9900-2026-105-3-308-313 (in Russian).

4. Kuz`min S.V., Rusakov V.N., Setko A.G., Sinicyna O.O. Toxic and hygienic aspects of the effects of cadmium on the human body when ingested with food (literature review). Zdorov`e naseleniya i sreda obitaniya. 2024; 32(7): 49–57. https://elibrary.ru/yjrsze (in Russian).

5. Genchi G., Sinicropi M.S., Lauria G., Carocci A., Catalano A. The Effects of Cadmium Toxicity. Int. J. Environ. Res. Public Health. 2020; 17(11): 3782. https://doi.org/10.3390/ijerph17113782

6. Jomova K., Alomar S.Y., Nepovimova E., Kuca K., Valko M. Heavy metals: toxicity and human health effects. Arch. Toxicol. 2025; 99(1): 153–209. https://doi.org/10.1007/s00204-024-03903-2

7. Afzal S., Abdul Manap A.S., Attiq A., Albokhadaim I., Kandeel M., Alhojaily S.M. From imbalance to impairment: The central role of reactive oxygen species in oxidative stress-induced disorders and therapeutic exploration. Front. Pharmacol. 2023; 14: 1269581. https://doi.org/10.3389/fphar.2023.1269581

8. Zolotavina M.L., Pashina E.V. Modern methodological problems of endogenous intoxication assessment. Nauka i mir. 2014; 11-2(15): 38–41. https://elibrary.ru/szirqp (in Russian).

9. Vinokurov M.M., Savel`ev V.V., Xlebny`j E.S., Kershengol`cz B.M. Comprehensive assessment of the level of endogenous intoxication in patients in the sterile phase of pancreatic necrosis. Khirurgiya. Zhurnal im. N.I. Pirogova. 2012; 10: 21–26. https://elibrary.ru/piwbkn (in Russian).

10. Sumarokova A.V., Bebyakova N.A. Assessment of metabolism by the level of low- and medium-molecular substances in women of the Arkhangelsk region. Zhurnal mediko-biologicheskix issledovanij. 2013; 2: 71–77. https://elibrary.ru/ytbsyl (in Russian).

11. Borodina Zh.I., Kamenshhikova T.M., Malinin O.V., Manakhov K.M. The importance of the content of substances of low and medium molecular weight in the pathogenesis of intoxication in hemorrhagic fever with renal syndrome. Medicinskij vestnik Bashkortostana. 2017; 72(6): 11–15. https://elibrary.ru/ytbsyl (in Russian).

12. Prokof`eva T.V., Polunina O.S., Polunina E.A., Sevost`yanova I.V., Voronina P.N. Assessment of endogenous intoxication based on the study of substances of medium and low molecular weight in patients with myocardial infarction on the background of chronic obstructive pulmonary disease. Medicinskij sovet. 2022; 16(17): 106–115. https://elibrary.ru/vvaiua (in Russian).

13. Tereshhenko O.A., Sergienko V.I., Petrosyan Ye.A., Botashev A.A., Pomeshhik Yu.V. The role of free radical oxidation and endothelial dysfunction in the pathogenesis of biliary peritonitis. Vestnik Rossijskoj voenno-medicinskoj akademii. 2013; 2: 116–119. https://elibrary.ru/raetrh (in Russian).

14. Karyakina E.V., Belova S.V. Average mass molecules as an integral index of metabolic disorders (review of literature). Klinicheskaya laboratornaya diagnostika. 2004; 3: 3–8. https://elibrary.ru/ojfspn (in Russian).

15. Margity` M.M., Marzhoxova M.Yu., Xadzegova S.B. The importance of the content of low and medium molecular weight substances and oligopeptides in the pathogenesis of chickenp. Mediko-farmacevticheskij zhurnal Pul`s. 2021; 23(6): 185–192. https://doi.org/10.26787/nydha2686-6838-2021-23-6-185-192 https://elibrary.ru/awxmdi (in Russian).

16. Miroshnikova D.I., Kiryushin V.A., Proxorov N.I., Fomina M.A., Motalova T.V., Bol`shakov A.M. Severity of endogenous intoxication and oxidative stress in the blood of workers in contact with glycine derivatives. Gigiena i sanitariya. 2019; 98(8): 851–856. https://elibrary.ru/fwufos (in Russian).

17. Tamás M.J., Fauvet B., Christen P., Goloubinoff P. Misfolding and aggregation of nascent proteins: a novel mode of toxic cadmium action in vivo. Current genetics. 2018; 64(1): 177–181. https://doi.org/10.1007/s00294-017-0748-x

18. E`delev N.S., Obuxova L.M., E`delev I.S., Katirkina A.A. Analysis of low and medium molecular weight substances for the differential diagnosis of death as a result of acute small-focal myocardial infarction and other forms of heart pathology. Sudebno-medicinskaya e`kspertiza. 2017; 60(2): 7–10. https://doi.org/10.17116/sudmed20176027-10 (in Russian).

19. Erlykina E.I., Kopytova T.V., Alyasova A.V., Gorshkova T.N., Terentiev I.G., Pimenov V.G. et al. Integral Analysis of Blood Plasma Biochemical Parameters as an Optimizing Diagnostic Technique of Epithelial Tissue Malignant Neoplasms. Sovremenny`e texnologii v medicine. 2013; 5(3): 51–58. https://elibrary.ru/replmz (in Russian).

20. Marzhoxova M.Yu., Bashieva M.A. The content of low and medium molecular weight substances in blood plasma, erythrocytes and urine in patients with acute Flexner dysentery. Infekcionny`e bolezni. 2008; 6(2): 33–36. https://elibrary.ru/jjzerf (in Russian).