Philosophiae Doctor - PhD / Introduction: Typha capensis, commonly referred to as bulrush also called "love reed'' growing in Southern Africa's wetlands, is one of South Africa indigenous medicinal plants that are traditionally used to treat male fertility problems and various other ailments. Previous studies revealed that T. capensis has indeed a beneficial effect on male reproductive functions and aging male symptoms. The T.capensis rhizomes are used in traditional medicine during pregnancy to ensure easy delivery, for venereal diseases, dysmenorrhea, diarrhoea, dysentery, and to enhance the male potency and libido. Typha genuses contain flavones and other phenolic compounds, which exhibit anti-oxidative capacity. Materials and Methods: This study encompasses three parts (part 1: Exposure of different cell lines to crude aqueous extracts of T. capensis rhizomes; part 2: HPLC analysis of Typha capensis crude rhizome extract and exposure of different cell lines to the F1 fraction of the summer season; part 3: Compound identification by means of NMR spectrometric analysis and exposure of different cell lines to bioactive compounds (Quercetin and Naringenin) isolated from T. capensis rhizomes. Part 1: TM3-Leydig cells and LNCaP cells incubated with different concentrations of crude aqueous extract of T. capensis rhizomes (0.01, 0.02, 0.1, 1, 10 and 100 μg/ml) and control (without extract) for 24 and 96 hours, after incubation. The following parameters were evaluated: cell morphology and viability (determined by means of MTT assay). Part 2: The crude extract HPLC profiles were obtained by preparing the extracts for different seasons (Autumn, Winter, Spring, Summer). TM3-Leydig cells, LNCaP cells and PWR-1E cells incubated with different concentrations T. capensis rhizomes extract F1 fraction of the summer season (0.01, 0.02, 0.1, 1, 10 and 100 μg/ml) and control (without extract) for 24 and 96 hours, after incubation. The following parameters were evaluated: cell morphology was observed and recorded, viability (determined by means of MTT assay), testosterone production (testosterone ELISA test), cell early apoptosis (determined by means of Annexin V-Cy3 binding), DNA fragmentation (determined by means of the TUNEL assay). Part 3: NMR spectrometric analysis was performed on a 13C spectra were recorded at 400 MHz. TM3-Leydig cells and LNCaP cells incubated with different concentrations of bioactive compounds (Quercetin and Naringenin) isolated from T. capensis rhizomes, for acute exposure (24, 96 hours) and chronic exposure (96 hours), after incubation, the following parameters were evaluated: cell morphology and viability (determined by means of MTT assay), testosterone production (testosterone ELISA test), cell early apoptosis (determined by means of Annexin V-Cy3 binding) and DNA fragmentation (determined by means of the TUNEL assay). Results: Part 1: for TM3-Leydig cells the results reveal no observable morphological changes and no significant influence on cell viability except at highest concentration indicating cellular stress. However, LNCaP cells showed a decline in cell viability at the incubation period 96 hours (-82.4%) more than 24 hours (-64.7%) indicating more cell death. Part 2: HPLC data showed that the most effective fraction was the F1 fraction from the summer harvest. Results revealed that the T. capensis rhizome extract F1 fraction of the summer season significantly enhanced testosterone production in TM3 cells and was more toxic towards cancer cells (LNCaP cells ) compared to the normal cell lines (TM3-Leydig, PWR-1E cells). Part 3: NMR data showed 2 bioactive compounds which were identified as Quercetin and Naringenin. The assays showed that LNCaP cells are more sensitive to the cytotoxic effects and apoptosis induction of both compounds, whereas, the assays resulted in weak effects toward TM3-Leydig cells. However, testosterone production in TM3-Leydig cells was significantly enhanced at low concentrations of Quercetin and Naringenin at all exposure types (acute and chronic) testosterone beak significantly at around 0.100 and 0.125 μg/ml (P<0.0001), stimulatory activity in a dose-dependent manner. Conclusion: Typha capensis enhanced the production of testosterone and might be useful to treat male infertility and aging male problems. Results further reveal that the F1 fraction from the summer harvest had highest biological activity. This study, for the first time, investigated the effects of bioactive compounds (Quercetin and Naringenin) yeilded from aqueous extraction of Typha capensis rhizomes in cell lines investigating male reproductive functions. Active compounds present in the rhizomes have caused an increased production of testosterone level in TM3-Leydig cells. Furthermore, the active compounds of Typha capensis rhizomes in the high dose had a negative effect on the percentage of DNA fragmentation in LNCaP cells. When compared to the effect of the low dose, the two compounds induced significant apoptosis in cancer cell line (LNCaP) compared with the normal cell line (TM3-Leydig). The isolated compounds are significantly selective towards the cancer cells than the normal cell compared with the exposure of bioactive compounds used in this study.

L’impact de l’utilisation des agropesticides sur la fonction de reproduction mâle est évalué chez des agriculteurs de Djutitsa (Ouest Cameroun). Le pesticide le plus utilisé par ces agriculteurs est testé in vivo sur la fonction de reproduction du rat mâle, ex vivo et/ou in vitro sur la stéroïdogenèse Leydigienne afin d’évaluer son implication dans les déséquilibres observés chez les agriculteurs. Ensuite, l’effet protecteur des extraits de Carpolobia alba et Basella alba contre les effets délétères dudit pesticide est évalué in vivo chez des rats mâles, ainsi que leur influence sur la production de la protéine de transport des stéroïdes (SHBG) par les cellules HepG2. Les résultats montrent que les agriculteurs utilisent 25 agropesticides et présentent des symptômes liés à une protection inadéquate. De plus, ils présentent une diminution de la testostérone avec une élévation de l’androstènedione sériques comparé au groupe témoin non exposé (P < 0,05) et ces déséquilibres androgéniques sont accompagnés de difficultés de reproduction. Le manèbe est l’agropesticide le plus utilisé et perturbe chez le rat mâle la stéroïdogenèse Leydigienne (à travers l’inhibition de la CYP11A1) et la fertilité. Cette fertilité est améliorée/rétablie lorsque le pesticide est concomitamment administré avec l’un des extraits, suggérant ainsi l’effet protecteur desdits extraits qui est imputable à leur activité androgénique également démontré chez les rats. Toutefois, ces extraits et le manèbe n’affectent pas la production de la SHBG in vitro. Ces résultats soulignent l’altération de la fonction de reproduction mâle par les agropesticides et l’effet bénéfique des plantes médicinales / The effect of agropesticides use on male reproductive function was evaluated in male farmers in Djutitsa (West Cameroon). The most frequently used agropesticide by farmers was selected and tested in vivo on the reproductive function of male rats, ex vivo and/or in vitro on Leydig cells steroidogenesis, in order to evaluate its implication in disorders observed in farmers. The ability of 2 Cameroonian medicinal plants (Carpolobia alba and Basella alba) to prevent pesticide-induced toxicity was also investigated in vivo in male rats. Furthermore, both extracts and selected pesticide were tested on the release of a steroid transporter protein (SHBG) by HepG2 cells. The results showed that farmers used 25 agropesticides and presented symptoms related to inadequate protection. Moreover, they had lower serum testosterone and higher androstenedione levels compared to a control group with no history of agropesticide exposure (P < 0.05), and these androgenic imbalances were accompanied by difficulties of reproduction. Maneb was the most common ingredient, and its administration to male rats resulted in decrease/alteration of Leydig cells steroidogenesis (through inhibition of CYP11A1) as well as fertility. The latter fertility was improved/restored when maneb was coadministrated to rats with any of the plant extracts, suggesting their protective effect that may be attributed to their proven androgenic activity. However maneb and the plant extracts did not affect SHBG release by HepG2 cells. These results highlight agropesticides deleterious effect on male reproductive function, which may be prevented by the investigated plant extracts