Dietary fluted pumpkin seeds induce reversible oligospermia and androgen insufficiency in adult rats

Abstract

Some components of the human diets are believed to be promising male contraceptive agents. The present study examined the antispermatogenic efficacy, reversibility and toxicity of fluted pumpkin seed-supplemented diet (DFPS) in adult male Wistar rats. Adult rats were given DFPS at 2.5, 5 and 10% for 60 days followed by 60 days post-treatment period. The control animals received normal standard rat diet not supplemented with fluted pumpkin seeds. The sperm quality variables, testosterone and follicle-stimulating hormone (FSH), oxidative status of the testis, steroidogenic enzymes and gamma-glutamyl transferase (γ-GT) activities and the histology of the testis were determined to evaluate the anti-fertility activity of fluted pumpkin seeds. Treatment of animals with DFPS at 5% and 10% resulted in decreased serum and intratesticular testosterone and FSH concentrations. This effect was associated with decreased activity of 17β-hydroxysteroid dehydrogenase (17β-HSD), increased testicular oxidative stress and poor sperm quality in the 10% diet group. After 60 days DFPS post-treatment, intra-testicular 17β-HSD and γ-GT activities, FSH and testosterone levels recovered to control values. Furthermore, poor sperm motility, count, morphology and viability as well as severe loss of spermatogonia and other matured epithelial germ cells and Sertoli cells observed especially in the 10% DFPS-treated animals reverted to nearly control values 60 days after withdrawal of treatment. Dietary fluted pumpkin seeds may selectively act on the epithelial germ cells, possibly mediated via Sertoli cells, leading to oligospermia, oxidative damage and androgen insufficiency. The reversibility of these effects to near normal levels after withdrawal of treatment justifies further consideration of DFPS as it may be an effective and readily reversible agent that meets the required criteria of a male contraceptive agent.

Fluted pumpkin seeds protect the spermatogenesis score index and testicular histology of caffeine treated rats

“…Interestingly, 100 mg kg −1 bw of the leaf extract of fluted pumpkin has better testiculo‐protective and spermatogenic effects in rats than at higher doses (200, 300 mg kg −1 bw) (Emmanuel et al, 2018), thereby supporting our present result of increased protective effect of FPS against CAFF‐induced testicular injury at lower doses than at higher doses. It is believed that the presence of phyto‐constituents in FPS including erucic acids, tannins, saponins and alkaloids have the potential to compromise testicular functions at higher doses but not at lower doses where it improves the activity of the testis (Abarikwu et al, 2022; Emmanuel et al, 2018; Njoku et al, 2019). Furthermore, due to the richness of fluted pumpkin in phenolic constituents and flavonoids as natural antioxidants, the hexane‐rich fractions of FPS are able to exert antioxidant protective effects on the testes of rats in response to CAFF treatment (Abarikwu et al, 2022; Ezim & Abarikwu, 2021).…”

“…Herbal preparations from several parts of fluted pumpkin have been employed in ethnobotany for the treatment of hypertension, diabetes, convulsion, anaemia, malaria, and chronic fatigue (Njoku & Abarikwu, 2021). The seeds of the plant have been demonstrated to possess anti‐diabetic activity (Eseyin et al, 2007), anti‐cancer effect (Okokon et al, 2012), antioxidant effect (Osukoya et al, 2016), anti‐inflammatory activity (Oluwole et al, 2005), sperm quality promoting effect (Njoku & Abarikwu, 2021), reversible effects on testicular functions (Njoku et al, 2019) and have therapeutic advantage against benign prostatic hyperplasia (Ejike & Ezeanyika, 2011). Other studies have also shown that fluted pumpkin seeds (FPS) serve as a chemopreventive agent, preserve spermatogenesis and inhibit oxidative stress in experimental rat models (Abarikwu et al, 2022; Akang et al, 2010; Ezim & Abarikwu, 2021; Njoku & Abarikwu, 2021).…”

Effects ofAnthocleista djalonensisroot extracts on reproductive hormones and testicular marker enzymes in adult male Wistar rats

“…The determination of testicular γ-GT activity was done as reported previously (Njoku et al, 2019). The samples (…”

“…The withdrawal of treatment for some of these extracts most of which find application in herbal medicine for the management of the fertility health of men, for example aqueous leaf extract of Azadirachita indica (Mishra & Singh, 2005), chloroform extract of Carica papaya seeds (D'Cruz, Vaithinathan, Jubendradass, & Mathur, 2010), dietary fluted pumpkin seeds (Njoku, Abarikwu, Uwakwe, Mgbudom-Okah, & Ezirim, 2019), rhizome extract of Curcuma longa (Mishra & Singh, 2009), water extract of Carica papaya seeds (Uche-Uwachi, Mitchell, & McEwen, 2011) and aqueous fruit extract of Mimusops elengi (Singh & Singh, 2016), could result in the recovery of spermatogenesis and treatment-related testicular alterations. The withdrawal of treatment for some of these extracts most of which find application in herbal medicine for the management of the fertility health of men, for example aqueous leaf extract of Azadirachita indica (Mishra & Singh, 2005), chloroform extract of Carica papaya seeds (D'Cruz, Vaithinathan, Jubendradass, & Mathur, 2010), dietary fluted pumpkin seeds (Njoku, Abarikwu, Uwakwe, Mgbudom-Okah, & Ezirim, 2019), rhizome extract of Curcuma longa (Mishra & Singh, 2009), water extract of Carica papaya seeds (Uche-Uwachi, Mitchell, & McEwen, 2011) and aqueous fruit extract of Mimusops elengi (Singh & Singh, 2016), could result in the recovery of spermatogenesis and treatment-related testicular alterations.…”

“…In the literature, post-treatment effects of plant extracts are often investigated under pathological and diseased states and after an initial induced toxicity state. The withdrawal of treatment for some of these extracts most of which find application in herbal medicine for the management of the fertility health of men, for example aqueous leaf extract of Azadirachita indica (Mishra & Singh, 2005), chloroform extract of Carica papaya seeds (D'Cruz, Vaithinathan, Jubendradass, & Mathur, 2010), dietary fluted pumpkin seeds (Njoku, Abarikwu, Uwakwe, Mgbudom-Okah, & Ezirim, 2019), rhizome extract of Curcuma longa (Mishra & Singh, 2009), water extract of Carica papaya seeds (Uche-Uwachi, Mitchell, & McEwen, 2011) and aqueous fruit extract of Mimusops elengi (Singh & Singh, 2016), could result in the recovery of spermatogenesis and treatment-related testicular alterations. But till date, there are no studies reported on the comparative results of treatment-and post-treatment-related effects of plant extracts in a non-diseased model.…”