Testicular morphometry of rats with Walker 256 tumor supplemented with L-glutamine

Abstract

Glutamine is often used to treat metabolic changes associated with anorexia-cachexia syndrome in patients with malignant neoplasms. Walker 256 tumor is an excellent model for studying these changes associated with cancer in different organs, including injuries in testicular functions. However, the effects of supplementing glutamine on testicular morphometry in this model have not yet been investigated. Thus, the objective of this study was to evaluate the effect of L-glutamine supplementation on testicular morphometry in rats transplanted with Walker 256 tumor cells. Forty puberty Wistar rats were divided into four groups: control without L-glutamine (C); control supplemented with L-glutamine (CG); inoculated with Walker 256 tumor cells (WT) and inoculated with Walker 256 tumor cells and supplemented with L-glutamine (WTG). The testicles were removed, weighed, fixed in Bouin, and included in paraffin for histomorphometric analysis. Walker 256 tumor caused quantitative changes in the tubular and intertubular compartments and tunica albuginea, with reductions in the percentages of lumen and tunica albuginea, number of Sertoli cells per gram of testis; number of Leydig cells; percentage of blood vessels and connective tissue in intertubule. However, glutamine supplementation prevented part of these changes caused by the tumor, presenting mainly a protective effect on the tunica albuginea and percentage of blood and lymph vessels in the intertubule. These results indicate the potential of L-glutamine was able to recover for testicular dysfunction associated with cancer.

Keywords: Walker carcinoma; histomorphometry; intertubule; seminiferous tubules; spermatogenesis.

Figure 1. Cross sections of the testicular parenchyma of Wistar rats with Walker 256 tumor and L-glutamine supplementation. (a) Control; (b) Control supplemented with L-glutamine; (c) Walker 256 tumor; (d) Walker 256 tumor supplemented with L-glutamine. TC: tubular compartment; L: lumen; SE: seminiferous epithelium; IC: intertubular compartment. Sections stained in H&E. Scale bars: 15 µm.

Figure 2. Higher magnification of testicular parenchyma sections of Wistar rats with Walker 256 tumor and L-glutamine supplementation. (a) Control; (b) Control supplemented with L-glutamine; (c) Walker 256 tumor; (d) Walker 256 tumor supplemented with L-glutamine. Degeneration on the seminiferous epithelium (white arrow). Detail in d showing detachment of tunica propria (black arrow). Tunica propria (arrowhead); Sections stained in H&E. Scale bars: 15 µm.

Figure 3. Frequency of the stages of the seminiferous epithelium cycle of Wistar rats with Walker 256 tumor and with L-glutamine supplementation. Pre-M: pre-meiotic phase; M: meiotic phase; Post-M: post-meiotic phase. C: Control; CG: Control supplemented with L-glutamine; WT: Walker 256 tumor; WTG: Walker 256 tumor supplemented with L-glutamine. Symbols indicate differences between groups, within each stage (*: CG x WTG comparison; #: C x WT comparison).

Figure 4. Intertubular compartment of Wistar rats with Walker 256 tumor and with L-glutamine supplementation. (a) Control; (b) Control supplemented with L-glutamine; (c) Walker 256 tumor; (d) Walker 256 tumor supplemented with L-glutamine. Leydig cell (white arrow); blood vessels (black arrow); lymphatic vessel (star); Connective tissue (arrowhead). TC: tubular compartment; Sections stained in H&E. Scale bars: 40 μm.