Age-dependent morphological, morphometric and Ki-67 proliferative changes in the rat testis under experimental...

Chronic renal failure (CRF), the advanced stage of chronic kidney disease (CKD), is a systemic disorder that affects extrarenal organs, including the male gonads, yet the age-related dynamics of testicular structural injury and its pharmacological correction remain insufficiently characterised. We evaluated age-dependent morphological, morphometric and proliferative (Ki-67) alterations of the testis in an experimental model of CRF and assessed the corrective potential of an infusion of Ferula moschata (sumbul) root, a plant used in regional traditional medicine and reported to possess antioxidant and anti-inflammatory activity.

The study was performed at Bukhara State Medical Institute (2023-2025) on 140 outbred male white rats aged 3, 6 and 9 months, allocated to three groups: intact control (Group I, n = 40); CRF induced by the Greven glycerol method (Group II, n = 50); and CRF followed by one month of oral Ferula moschata root infusion (Group III, n = 50). CRF was confirmed biochemically (serum urea and creatinine) and by renal histology. Testes were assessed by organometry, light microscopy (haematoxylin-eosin, H&E, and van Gieson staining), quantitative morphometry (tunica albuginea thickness, seminiferous tubule diameter and cross-sectional area, germinal epithelium thickness, tubular lumen diameter) and Ki-67 immunohistochemistry (IHC) with digital quantification (QuPath 0.5.0, ×200). Data (M ± m) were analysed after Kolmogorov-Smirnov normality testing using the two-sample Student t-test and the Mann-Whitney U-test, with significance at p ≤ 0.05.

CRF produced progressive, age-amplified testicular injury. Relative to age-matched controls, seminiferous tubule diameter fell from 178.1 ± 1.04-151.62 ± 1.84 µm at 6 months and from 163.2 ± 1.1-140.34 ± 2.19 µm at 9 months, tubule cross-sectional area and germinal epithelium thickness decreased, and the tunica albuginea thickened; the germinal epithelium thinned by 8.1% at 3 months, 25.5% at 6 months and ∼30% at 9 months. Ki-67 proliferative expression, which physiologically peaked at 6 months in controls (35.9%, 44.23% and 23.2% at 3, 6 and 9 months), fell markedly under CRF (18.1%, 10.74% and 2.94%; 3-8-fold lower than control). One month of Ferula moschata correction partially restored the morphometric indices (e.g., 6-month tubule diameter to 160.29 ± 2.24 µm) and increased Ki-67 expression (25.12%, 32.9% and 12.1%; 2-6-fold higher than CRF), approaching control values. Recovery was greatest in younger animals and least in 9-month-old rats.

Experimental CRF induces age-dependent structural degeneration and suppressed proliferative activity in the rat testis, which are partially reversible by Ferula moschata root infusion, most effectively when treatment begins at a younger age. Ki-67 is a reliable marker of the CRF-related decline in testicular proliferation, and Ferula moschata root merits further study as an adjuvant gonadoprotective phytotherapeutic.