Royal jelly alleviates gemcitabine-induced ovarian toxicity: an investigation on rat models

Abstract

Background: Royal Jelly (RJ), an important product of apitherapy, has been traditionally used for its various health benefits, particularly for its anti-inflammatory, antioxidant, and immune-modulatory properties. RJ's ability to reduce oxidative stress, inflammation, and cellular damage has made it a promising candidate for preserving ovarian function and fertility during cancer treatments. Gemcitabine (GEM) is an antimetabolite chemotherapeutic drug known to cause ovarian toxicity. To date, there has been no study evaluating the protective effects of RJ specifically against GEM-induced ovarian damage, making this an original contribution to the field. This study investigated RJ's protective effects against GEM-induced ovarian toxicity in rats.

Method: Thirty-two female Wistar-Albino rats were divided into four groups: Control, RJ, GEM, and GEM + RJ. GEM (200 mg/kg) was administered intraperitoneally, while RJ (100 mg/kg) was given orally for one week before GEM administration. Histopathological, immunohistochemical, and biochemical analyses were performed to assess ovarian tissue damage, inflammation, and oxidative stress markers.

Results: GEM treatment caused ovarian damage, including vascular congestion, vacuolization, and Hemorrhage. RJ partially suppressed GEM-induced increases in TNF-α, IL-1β, and IL-6 levels and enhanced AMH expression only in primary follicles. Additionally, RJ only partially lowered FSH levels while increasing LH levels. RJ also counteracted GEM-induced oxidative stress by reducing MDA levels and partially enhancing SOD and CAT activity. GEM caused ovarian damage, including vascular congestion, vacuolization, hemorrhage, inflammation, and oxidative stress.

Conclusions: RJ partially reduced inflammatory response and oxidative stress, supported follicular development, increased AMH expression, and alleviated histopathological damage. This original study highlights the potential of RJ as a natural adjunct to preserve ovarian reserve during gemcitabine chemotherapy, while emphasizing the need for further research to determine its long-term effects and optimal dosage.

Fig. 1

Light microscopic findings in the rat ovary tissue. Control group: Several developmental phases of folliculi are found. GEM group: There were noticeably fewer follicles at various stages of development. GEM + RJ group: a considerable number of follicles in different growth phases are detected in this group compared to the GEM group. Primordial follicles (*), primary follicles (PF), the secondary follicle (SF), and Corpora lutea (CL) with large, weakly pigmented acidophilic cells and atretic follicles (AF). Blood vessels congestion (red arrow), vacuolization (red arrowhead), and (red +) hemorrhage. H&E: hematoxylin-eosin and Masson’s trichrome staining (Olympus BX51, Tokyo, Japan. X20)

Fig. 2

Blood vessels congestion, vacuolization, and hemorrhage ovary histoscore in the experimental groups. Values are represented as mean ± SD using (Kruskal-Wallis) followed as a post-hoc Dunn’s test, respectively. For n = 8 *p < 0.05, **p < 0.01, or ***p < 0.001. Groups in the same line were indicated by identical symbols if they were similar, and by distinct symbols if they were distinctive

Fig. 3

Graphical representation of follicle scores in experimental groups. Values are represented as mean ± SD using ANOVA and Kruskal-Wallis followed as a post-hoc test Bonferroni and Dunn’s test, respectively. For n = 8 *p < 0.05, **p < 0.01, or ***p < 0.001

Fig. 4

Immunohistochemical microscopic findings in experimental groups. Expressions of proinflammatory markers TNF-α, IL-1β, and IL-6 in ovarian tissue of all experimental groups. (Olympus BX51, Tokyo, Japan. X20)

Fig. 5

Graphical representation of immunohistochemical findings. Effect of RJ administration on (a) TNFα, (b) IL1β and (c) IL6 in GEM -treated rats. Values are represented as mean ± SD using ANOVA followed as a post-hoc test Bonferroni, respectively. For n = 8 *p < 0.05, **p < 0.01, or ***p < 0.001. Groups in the same line were indicated by identical symbols if they were similar, and by distinct symbols if they were distinctive

Fig. 6

Immunohistochemical microscopic findings (a) and graphics (b). Expressions of PTEN markers in ovarian tissue of all experimental groups. Values are represented as mean ± SD using ANOVA followed as a post-hoc test Bonferroni, respectively (c). For n = 8 *p < 0.05, **p < 0.01, or ***p < 0.001. (Olympus BX51, Tokyo, Japan. X20)

Fig. 7

Immunohistochemical microscopic findings (a) and graphics (b). Expressions of AMH markers in ovarian tissue of all experimental groups. Values are represented as mean ± SD using ANOVA and Kruskal-Wallis followed as a post-hoc test Bonferroni and Dunn’s test, respectively (c). For n = 8 *p < 0.05, **p < 0.01, or ***p < 0.001. (Olympus BX51, Tokyo, Japan. X20). Groups in the same line were indicated by identical symbols if they were similar, and by distinct symbols if they were distinctive

Fig. 8

A statistical analysis of the experimental groups’ serum levels of MDA (a), GSH-PX (b), SOD (c), and CAT (d), expressed graphically. Values are represented as mean ± SD using ANOVA and Kruskal-Wallis followed as a post-hoc test Bonferroni and Dunn’s test, respectively. *p < 0.05, **p < 0.01, ***p < 0.001

Fig. 9

A statistical analysis of the experimental groups’ AMH (a), FSH (b), and LH (c) hormone levels expressed graphically. Values are represented as mean ± SD using ANOVA followed as a post-hoc test Bonferroni, respectively. For n = 8,. *p < 0.05, **p < 0.01, ***p < 0.001