تقييم الدور الوقائي للمستخلص المائي لاوراق نبات القراص Urtica dioica في بعض المعايير الفسلجية والنسجية في ذكور الجرذان البيض المستحثة بالعلاج الكيميائي Cisplatin

Evaluation of the Protective Role of the Aqueous Extract of Urtica dioica Leaves on Some Physiological and Histological Parameters in Male Albino Rats Induced with the Chemotherapeutic Agent Cisplatin

The present study aimed to evaluate the protective effect of the aqueous extract of Urtica dioica (Ud) leaves and to investigate its role against potential damage in some testicular and epididymal tissues of male albino rats induced with the chemotherapeutic drug Cisplatin (Cis). This goal was achieved through the assessment of certain physiological parameters, oxidants and antioxidants, and histological changes in the testes and epididymis. The experiment was conducted at the Postgraduate Laboratory, Department of Biology, College of Education for Pure Sciences, University of Karbala, during the period from February to May 2024. The chemical composition of the aqueous extract of Urtica dioica leaves was analyzed, and its protective role against cisplatin-induced reproductive toxicity was examined.
The study included 60 rats and was carried out in two experiments. The first experiment aimed to determine the most effective concentration among three safe doses of the extract. It involved 28 adult male rats, aged 11–15 weeks and weighing 200–320 g, obtained from the Animal House, College of Pharmacy, University of Karbala. They were randomly divided into four groups (seven rats each). The first group served as the negative control, while the other three groups were orally administered the aqueous extract at doses of 200, 400, and 600 mg/kg, respectively, followed by intraperitoneal injection of cisplatin (7 mg/kg) after one hour. This protective regimen continued for 30 days, with cisplatin injections repeated twice per month. Blood samples were collected to estimate the activity of superoxide dismutase (SOD), which was adopted as the main criterion for selecting the most effective extract concentration, found to be 600 mg/kg.
The second experiment was designed to evaluate the protective role of the extract at the selected concentration. It included 32 adult male rats, randomly distributed into four groups (eight rats each) for two months. The first group served as the negative control, while the second group received intraperitoneal cisplatin injections (7 mg/kg, twice per month). The third group was orally administered the aqueous extract (600 mg/kg), while the fourth group was treated orally with the extract followed by intraperitoneal cisplatin injection (7 mg/kg, twice per month), considered as the protective group. Rats were weighed at the beginning and end of the experiment. At the end, animals were anaesthetised, and blood samples were collected 24 hours after the last dose. Serum samples were analyzed for reproductive hormones [Testosterone (T), Interstitial Cell Stimulating Hormone (ICSH), and Follicle Stimulating Hormone (FSH)], the oxidative stress marker Malondialdehyde (MDA), and the antioxidant markers Glutathione (GSH), Catalase (CAT), and SOD. The testes and epididymis were excised, cleaned, and weighed. Semen samples were collected from the left epididymis for sperm parameters (motility, viability, and percentage of normal morphology). The lift testes were used to measure seminiferous tubule diameters, germinal layer thickness, spermatogonia, primary and secondary spermatocytes, spermatids, Sertoli cells, and Leydig cells. The epididymis was examined for duct diameters, cavity size, and epithelial thickness. Histopathological examination of the right testis and epididymis was also performed.
Phytochemical screening of the aqueous extract revealed the presence of tannins, carbohydrates, glycosides, phenols, resins, flavonoids, saponins, alkaloids, and coumarins. The results indicated that cisplatin caused significant reproductive organ toxicity, evidenced by a marked decrease (P≤0.05) in testicular and epididymal weights, sperm parameters, reproductive hormones (T, ICSH, FSH), antioxidant enzymes (SOD, GSH, CAT), seminiferous tubule diameters, germinal layer thickness, spermatogonia, spermatocytes, spermatids, Sertoli cells, Leydig cells, and epididymal epithelial thickness, alongside a significant increase (P≤0.05) in MDA levels, seminiferous tubule luminal diameters, and epididymal cavity diameters, compared with the negative control. Body weight gain, however, showed no significant difference (P>0.05).
On the other hand, the results showed a significant increase (P≤0.05) in the rate of body weight gain, the absolute weight of the testes and epididymis, histological parameters and sperm parameters (motility, vitality, and percentage of normal shapes), T hormones, ICSH, FSH, SOD, GSH, CAT levels, the average diameter of the seminiferous tubules, the thickness of the germinal layer, spermatogonia, primary spermatocytes, secondary spermatocytes, spermatoblasts, Sertoli cells, Leydig cells, the diameters of the epididymis and the thickness of the epididymal layer, and a significant decrease (P≤0.05) in the level of MDA, the average diameters of the lumen of the seminiferous tubules, and the diameters of the lumen of the epididymis in animals of the extract-only group and the preventive group (third and fourth) respectively compared to the positive control group. No significant difference (P>0.05) was observed in the amount of gain. Body weight gain was significantly different between the two groups. While the combined protective effect of nettle leaves could significantly improve the above parameters at the studied doses when compared to cisplatin alone, histological sections of the reproductive organs revealed pathological changes in the testicular and epididymal tissues of the cisplatin-treated animals compared to the control group. Cisplatin caused shrinkage of the testicular tissue, disruption of spermatogenesis, disintegration of the germinal layer, and a decrease in the diameter of the epithelial layer. It also caused a decrease in the number of sperm in some seminiferous tubules and a decrease in their quantity in the lumen of others. It also resulted in a significant decrease in the diameters of spermatocytes and Sertoli cells. There was also a significant decrease in spermatogenesis, spermatocytes, secondary spermatocytes, and spermatids, along with spermatids. Cisplatin also caused dilation of the tubular lumen and interstitial tissue, indicating a distorted testicular tissue structure. Regarding the epididymal tissue, the examination results for the cisplatin-only group showed interstices between the epididymal tubules, reduced epididymal diameters, thickened epithelial layer, degeneration of some smooth muscle cells surrounding the tubule, and widening of the epididymal cavities. In contrast, the histological sections of the extract-only and preventive groups showed significant improvement in histological changes, which were close to those of normal tissue, compared to those observed in the cisplatin-treated group.
In conclusion, the aqueous extract of Urtica dioica leaves at 600 mg/kg demonstrated a protective effect by alleviating the adverse effects of cisplatin through improving reproductive hormone levels, enhancing sperm motility and viability, and maintaining testicular integrity via boosting antioxidant enzymes and reducing free radical production.