Phytochemical properties of Curcuma caesia Roxb. improve sperm quality, testosterone levels, and testicular histology in male mice

Background Medicinal plants used in traditional systems of medicine are a valuable source of bioactive compounds with therapeutic potential against oxidative stress–related disorders, including male infertility. Curcuma caesia Roxb. is an ethnomedicinally important species known for its antioxidant, anti-inflammatory, and aphrodisiac properties; however, its effects on male reproductive function remain insufficiently characterized. Purpose This study aimed to evaluate the metabolites composition and dose-dependent effects of C. caesia extract on sperm quality, testicular histology, and testosterone levels in male mice. Methods A total of 24 male mice were divided into four groups (n = 6) using a completely randomized design. The ethanol extract of C. caesia rhizomes was dissolved in distilled water and administered at designated doses: 364 mg/kg BW (P1), 728 mg/kg BW (P2), and 1,092 mg/kg BW (P3). Plant metabolites were quantified via spectrophotometry and GC-MS analysis. Serum testosterone levels were measured using ELISA, while testicular histology and morphometric parameters were assessed using hematoxylin–eosin staining and microscopic imaging. Results Analysis revealed the presence of flavonoids, phenolics, tannins, and alkaloids. The P3 treatment significantly improved sperm concentration by 155% compared to the control. However, the P2 treatment yielded the highest percentage of viable spermatozoa (85.78%), motility (39.28%), and normal morphology (84.67%), alongside enhanced seminiferous tubule structure and spermatogenic cell density. These effects are attributed to the ROS-scavenging activity of phytochemicals, which preserve cellular morphology and support spermatogenesis. Serum testosterone levels increased in a dose-dependent manner, correlating with Leydig cell proliferation. Notably, while the moderate dose (P2) resulted in optimal reproductive outcomes, the highest dose (P3) showed a decline in sperm quality and histological alterations. Conclusion C. caesia enhances male reproductive functions, supporting its traditional use as a fertility-enhancing medicinal plant. However, its effects are dose-dependent, with optimal benefits observed at moderate concentrations and potential toxicity at higher doses. These findings provide novel preclinical evidence for the use of C. caesia in managing male infertility and establish a pharmacological basis for future clinical investigations.