Aphrodisiac and androgenic effects of the aqueous extract of the roots of Vepris afzelii on cyproterone acetate-induced hypogonadism in rat

This work aimed to evaluate the effects of the aqueous extract of Vepris afzelii roots on a rat model of hypogonadism. Phytochemical screening and acute toxicity of the extract were performed using different procedures. Hypogonadism was induced orally in adult Wistar rats using cyproterone acetate (30 mg/kg) for ten days. Besides six normal rats (10 ml/kg of distilled water, normal control), 30 hypogonadal rats were subdivided into five groups of six animals each, receiving for 14 days: distilled water (10 ml/kg, hypogonadal control), testosterone (4 mg/kg/3days) and the extract of V. afzelii (100, 200 and 400 mg/kg). Sexual behavior, sperm parameters, testes function and structure were assessed. Compared to the normal controls, significant (p = 0.0000) increases in mount (24 ± 0.94 seconds vs. 1200 ± 00 seconds) and intromission (49.16 ± 10.85 seconds vs. 1200 ± 00 seconds) latencies, and post-ejaculatory interval (381.72 ± 37.55 seconds vs. 1200 ± 00 seconds) were observed in all groups receiving cyproterone acetate on day 0. Total inhibitions of mounts (63.50 ± 8.91 vs. 00 ± 00), intromissions (36.66 ± 3.51 vs. 00 ± 00) (p = 0.0000), ejaculations (2.83 ± 00 vs. 00 ± 00, p = 0.0002) frequencies and mean copulatory interval (627.30 ± 81.80 vs. 00 ± 00, p = 0.0000) were also observed in these groups. Moreover, decreases in daily sperm production (2.65 ± 0.19 vs. 1.17 ± 0.08, p = 0.0498), percentage of sperm mobility (78.64 ± 8.41 vs. 10.12 ± 2.32), serum testosterone level (8.39 ± 0.63 ng/dl vs. 1.68 ± 0.19 ng/dl), diameter of seminiferous tubules (111.97 ± 0.51 µm vs. 94.51 ± 0.57 µm) and height of germinal epithelium (46.58 ± 0.34 µm vs. 33.74 ± 0.66 µm) (p = 0.0000) associated with increases in sperm transit (3.13 ± 0.45 vs. 11.07 ± 1.45, p = 0.0000) were also observed in these groups. Interestingly, compared to hypogonadal control and day 0, the administration of V. afzelii extract induced significant (p = 0.0000) improvements in all these altered parameters with 400 mg/kg being the most active dose. These results, attributed to saponins, flavonoids, polyphenols and triterpenes detected in this plant's extract confirm its traditional usage and could be useful for the management of patients suffering from hypogonadism.

Ethanolic extract of Persea americana Mill. (Lauraceae) seeds induced antiestrogenic effects in young female Wistar rats

OBJECTIVES

The ethanol extract of Persea americana seeds was found to inhibit the development of estrogen-dependent conditions in female Wistar rats, suggesting the ability of its secondary metabolites to interact with estrogen receptors (ERs), either as partial agonists or as antagonists. To test this hypothesis, the abovementioned extract was assessed for its ability to mimic and/or antagonize estradiol effects.

METHODS

Two experiments were conducted in ovariectomized (OVX) rats: (1) animals were treated with estradiol valerate (E2V; 1 mg/kg) or P. americana at doses of 25 and 50 mg/kg; (2) animals were treated with E2V alone (0.75 mg/kg) or in combination with P. americana at the abovementioned doses. Treatments were given orally for 3 days and animals were sacrificed for biochemical and histological analyses of the uterus and vagina.

RESULTS

When administered alone, P. americana did not change the histomorphology of both organs (uterus and vagina). In combination with E2V, P. americana decreased uterine weight [30 % decrease (p<0.001) at 25 mg/kg and 24 % (p<0.01) at 50 mg/kg] and epithelium height (37 % decrease). This was associated with decreased estradiol levels (at least 86 % decrease, p<0.001) in the uterus. Similarly, vagina epithelium height decreased by at least 34 % (p<0.05) when E2V was co-administered with P. americana.

CONCLUSIONS

The seed extract of P. americana contains ER antagonist secondary metabolites accounting for its ability to inhibit the development of estrogen-dependent conditions in female rats.

Factors Associated with COVID-19 Vaccine Refusal: A Community-Based Study in the Menoua Division in Cameroon

COVID-19, which was named in March 2020 as a global pandemic by the WHO, remains a serious public health threat worldwide. Despite the adoption of vaccines as an effective strategy to counter this pandemic, the vaccination rate in Cameroon is far lower than that planned by the Cameroonian government and its partners. The main objective of this study was to determine the factors limiting COVID-19 vaccine acceptance in the Menoua Division in the West Region of Cameroon. A community-based cross-sectional and analytical study was conducted between March and April 2022 in the Menoua Division. A pre-tested questionnaire was filled out by willing participants of more than 18 years old, and data were further expressed in order to estimate the knowledge of participants on COVID-19, vaccine status, and the factors associated with vaccine refusal. A Pearson test was performed in order to identify the associated factors, with a p-value < 0.05 considered as significant. A total of 520 participants with a mean age of 33.27 ± 12.78 were included. Most had a secondary education level (56.15%), and trade and informal sectors (34.04%) were the main occupations. Knowledge on COVID-19 was average, and it was significantly associated (p < 0.05) with gender and education level. The vaccination rate was 10%, which was six times less than the national target. A lack of information, confidence, and medicinal plant use were all factors significantly associated with vaccine refusal. This pioneer community-based study in Cameroon identified a lack of knowledge, confidence, and medicinal plant use as the leading factors limiting COVID-19 vaccine acceptance in Cameroon. Health authorities should therefore strengthen sensitization in order to tackle the lack of information and the misinformation among the target groups.

Amaranthus hybridus (Amaranthaceae) prevents the detrimental effects of cyclophosphamide on ovarian function in Wistar rats: An experimental study

Background

Cyclophosphamide (CP) is an anticancer agent, but its chronic administration induces ovarian toxicity.

Objective

We evaluated the effects of aqueous extract (AE) and methanol extract (ME) of Amaranthus hybridus (A.hybridus) on CP-induced ovarian toxicity in rats.

Materials and Methods

40 female Wistar rats (10 wk, 170-200 gr) were distributed into 8 groups (n = 5/each) as follows: 1) healthy control; 2) CP+distilled water (10 ml/kg/d); 3) CP+3%-tween 80 (10 mL/kg/d); 4) CP+clomiphene citrate (2 mg/kg/d); 5, 6) CP+AE of A. hybridus (55 and 110 mg/kg/d); and 7, 8) CP+ME of A. hybridus (55 and 110 mg/kg/d). After 28 days of treatment, estrus cyclicity, ovarian and uterine weights as well as estradiol levels and ovarian histology were determined.

Results

CP induced ovarian toxicity after 28 days of exposure. More specifically, CP disturbed the estrus cycle, decreased ovary and uterus weights (p = 0.04), and the 17-β estradiol level (p = 0.04), and induced severe ovarian damages. Remarkably, A. hybridus significantly increased (p = 0.03) the ovarian weight (AE and ME at all doses) and uterus weight (ME at 110 mg/kg/d), compared with the CP-treated rats. Moreover, the 17-β estradiol level was significantly elevated (p = 0.02) in rats given clomiphene citrate and A. hybridus (AE 110 mg/kg/d; ME 55 mg/kg/d). Finally, the ovaries of rats given plant extracts had many corpus luteum and normal follicles, and no cystic follicles.

Conclusion

prevented the detrimental effects of CP on ovarian function, which could support its traditional use as a fertility enhancer.

Pro-Sexual Effects of Aqueous and Methanol Extracts of Phyllanthus muellerianus (Kuntze) Exell (Phyllanthaceae) on a Model of Low Sexual Desire Disorder in Female Rats

Low sexual desire disorder is a recurrent deficiency in desire for sexual activity which impairs lifestyle. It is a frequent problem in women with limited therapeutic options. Phyllanthus muellerianus (Kuntze) Exell is a plant used by traditional healers to boost libido in women. This study aimed at evaluating the aphrodisiac properties of root barks extracts of this plant on a model of Low Sexual Desire Disorder (LSDD) in female rats. Low sexual desire was induced by ovariectomy plus low steroid hormones supplementations. Thirty ovariectomized rats were treated for 21 days with either distilled water, aqueous or methanol extracts (60 or 372 mg/kg) of P. muellerianus. All animals were supplemented with a low dose of 17β-estradiol and progesterone prior to sexual behavior test. Sexual behavior test was performed each week by pairing each female rat with a sexually experienced male. Sexual motivation (approach, ear wiggling, hops and darts, anogenital presentation and aggressive behavior frequency) and sexual receptivity parameters (lordosis frequency and quotient) were recorded. At the end of treatments, animals were sacrificed, uteri and vagina collected, weighed and conserved for total uterine proteins assay and histology. LSDD was characterized by significant inhibition of sexual motivation parameters and lordosis frequency compared to a normal control. Moreover, poor reproductive tissues growth characterized by low total uterine proteins, uterine wet weight and uterine epithelia size was noted in LSDD group compared to normal control. Interestingly, plant extracts significantly improved sexual motivation parameters (p < 0.05-0.001) compared to LSDD group. In addition, moderate reproductive tissues growth was noted in plant treated groups as confirmed by amelioration of uterine cell integrity. Present results show that P. muellerianus exhibits pro-sexual effects through amelioration of sexual motivation and reproductive tissues growth on a model of LSDD.

The edible plant Amaranthus hybridus (Amaranthaceae) prevents the biochemical, histopathological and fertility impairments in colibri®-treated female rats

Colibri® a commercial formulation of Imidacloprid severely impairs the reproductive function. This study aimed at evaluating the preventive effects of Amaranthus hybridus on the reproductive toxicity of colibri® in female rats. Eighty rats (n = 10/group) were orally treated with colibri® (22.5 mg/kg) and co-administered with either aqueous or methanolic extracts of A. hybridus (55 or 110 mg/kg) within four weeks. Control animals received either distilled water (10 ml/kg), clomiphene citrate or vitamin E. Starting from day 18 of treatment till the end, half of animals in each group (n = 5) was used for the fertility test whereas the remaining rats were kept under treatment until sacrifice. Blood, ovaries, uterus and vagina were collected after sacrifice for measurement of sexual hormones, oxidative stress markers and histological assessment. Exposure of female rats to colibri® was followed by a significant reduction (p < 0.05) in the ovarian and uterine weights, LH, FSH, estradiol and progesterone levels as well as ovarian superoxide dismutase, catalase and peroxidase activities. Moreover, alteration of ovaries, uteri and vagina histology, increase in MDA concentration, decrease in fertility and parturition indices and, pup's viability were recorded. Co-administration of colibri® and plant extracts significantly (p < 0.05-0.001) prevented the above-mentioned damages through biochemical parameter regulations. These results suggest that A. hybridus exerts a preventive effect against colibri®-induced female reproductive toxicity.

Use of WhatsApp®, for distance teaching during COVID-19 pandemic: Experience and perception from a sub-Saharan African setting

BACKGROUND

In the midst of the COVID-19 pandemic, to palliate to the lockdown and cover academic programs, the faculty of medicine and pharmaceutical sciences (FMPS) of the university of Dschang (UDs) in Cameroon has implemented e-learning using WhatsApp®.

AIM

Describe the opinion of students and lecturers after its implementation of e-learning at the FMPS of UDs.

METHODS

We designed a uniform teaching scheme using WhatsApp® during the university lockdown. Students and members of the teaching staff of the FMPS of UDs were enrolled after receiving clear information on the study implementation. At the end of the online-teaching period of two and a half months, we surveyed our students and teaching staff. Sociodemographic characteristics and opinions about e-learning were collected using a standard questionnaire.

RESULTS

We enrolled 229 students and 40 lecturers of the FMPS. Students reported a decremented quality of internet connection (p < 0.001, p-homogeneity < 0.001) despite an increased expenditure related to internet use. Electronic devices were broadly used before the implementation of mobile learning. The use of course materials was significantly more challenging among students because of the size/format of lecture notes and internet connection/cost (all p < 0.05). Perception of discipline compared to classroom-based lessons was not significantly different among students compared to lecturers (all p > 0.05). While lecturers were mainly more comfortable conveying the contents of their lectures, students tended to be less prone to actively participate. The motivation and satisfaction of the latter group toward e-learning were modest compared to classroom-based lectures while their feedback about the organization was positive.

CONCLUSIONS

E-learning using WhatsApp® could be an effective alternative to conventional classroom-based lessons in the context of COVID-19 pandemic. The use of a blended-learning program including classroom-based sessions could help improve its limitations.

Uterotonic Effects of Aqueous and Methanolic Extracts of Lannea acida in Wistar Rats: An In Vitro Study

Lannea acida (Anacardiaceae), commonly called Kikié in the Noun division (West-Cameroon), is a tree whose bark is used locally to facilitate delivery. This study was aimed at evaluating the in vitro uterotonic effects of aqueous and methanol extracts of L. acida in Wistar rats. Uterine strips isolated from rats pretreated with 5 μg estradiol (48 h) were mounted in a single-organ bath containing aerated and thermostated De Jalon solution (37 °C). After equilibration, non-cumulative effects of L. acida extracts were recorded after application. The effect of the methanol extract (the most active extract) was monitored in the presence of atosiban (a competitive antagonist of oxytocin receptors), atropine (a specific type 3 muscarinic receptor antagonist), nifedipine (an L-type calcium channel antagonist), and 2-Aminoethoxydiphenyl borate (2-ADB, a specific antagonist of inositol 1,4,5-triphosphate receptors type 1), and in calcium-free medium containing EGTA to elucidate its mechanism of action. L. acida induced uterine contraction in a concentration-dependent manner with the methanol extract (1.506 ± 0.032 gf) being the most effective. Administration of atosiban (2 μmol/L) and atropine (1 μmol/L) reduced the contractile effect of L. acida. Complete inhibition was observed with nifedipine, 2-APB, and calcium-free medium containing EGTA. These results suggest that L. acida possesses uterotonic effects mediated through oxytocin receptors with mobilization of extracellular calcium.

Dracaena arborea improves sperm characteristics and antioxidant enzymes in adult male rats with experimental varicocele

Objective:

We evaluated the preventive effects of aqueous and ethanolic extracts of Dracaena arborea on sperm characteristics and oxidative stress markers in adult male rats with varicocele.

Methods:

Thirty-six male Wistar rats were randomly distributed into 6 groups (6 animals/group) and treated for 30 days as follows: (1), normal rats receiving distilled water (10 ml/kg); (2), sham operated rats receiving distilled water (10 ml/kg); (3), varicocele rats receiving distilled water (10 ml/kg); (4), varicocele rats receiving vitamin E (150 mg/kg); (5-6), varicocele rats administered respectively with aqueous (500 mg/kg) and ethanolic (100 mg/kg) extracts of D. arborea. All rats (except normal and sham-operated groups) underwent varicocele induction. At the end of the treatment period, sexual organ weights, oxidative stress, sperm characteristics and some biochemical parameters were measured.

Results:

A significant decrease (p<0.01) in sperm density (137.81±7.76 vs. 175.83±4.86), sperm motility (55.43±4.49 vs. 77.96± 3.15) and sperm normality (44.75±2.80 vs. 79.25±1.84) was noticed in varicocele-untreated rats compared with controls. Varicocele also induced oxidative stress by decreasing superoxide dismutase (SOD) and catalase activities, and increasing malondialdehyde (MDA) levels. These alterations were prevented by D. arborea. For instance, the aqueous extract of D. arborea (500 mg/kg) significantly increased (p<0.05-0.001) testes and epididymis weights, sperm viability and sperm motility, while the ethanolic extract (100 mg/kg) increased sperm normality compared with varicocele-untreated rats. D. arborea extracts also decreased MDA levels, but elevated catalase activity.

Conclusions:

Dracaena arborea prevents the deleterious effects of varicocele and could be considered as an alternative treatment of this physiopathology.

Cytoarchitectural improvement in Leydig cells of diabetic rats after treatment with aqueous and ethanol extracts of Dracaena arborea (Dracaenaceae)

BACKGROUND AND AIM

Recent studies have demonstrated the androgenic effects of Dracaena arborea in castrated and diabetic rats, but the cytoarchitectural mechanism at the level of Leydig cells (LCs) justifying this improvement in androgens production in diabetic rats has never been examined. We investigated the effects of aqueous and ethanol extracts of D. arborea on diabetes-induced cytoarchitectural impairments of LCs in rats.

EXPERIMENTAL PROCEDURE

Besides a normal group, 4 groups of diabetic rats were treated orally with Millipore water (10 ml/kg, diabetic), sildenafil citrate (1.44 mg/kg), aqueous (500 mg/kg) and ethanol (100 mg/kg) extracts of D. arborea for 21 days. On day 22, rats were sacrificed and the testes were removed and prepared for electron microscopic analyses of LCs ultrastructure.

RESULTS AND CONCLUSION

The ultrastructure of LCs in control rats was normal, while that in diabetic rats exhibited large heterochromatization in the nuclei, reduced amount of smooth endoplasmic reticulum with no lipid droplets in the cytoplasm, many autophagosomes and degenerated mitochondria containing lots of electron dense granules in the matrix. Interestingly, treatment with D. arborea especially its aqueous extract (500 mg/kg) alleviated these impairments, characterized by a rarification of heterochromatization in the nuclei coupled to an increase and the presence in the cytoplasm of prominent smooth endoplasmic reticulum and a reduction of electron dense granules in the matrix of mitochondria. These alleviating properties of D. arborea on LCs ultrastructure of diabetic rats could explain its androgenic potential. These results are useful for the management of patients suffering from diabetes-induced hypogonadism.

Prevalence and factors associated with dysmenorrhea in women at child bearing age in the Dschang Health District, West-Cameroon

Introduction

dysmenorrhea is a painful phenomenon at the pelvis region preceding or following menstruation. Dysmenorrhea accounts among the most frequent problem of women at child bearing age and affects 45% to 95% of them. According to the WHO, 16.8 to 81% of women are affected by dysmenorrhea. The present study was carried out at the Dschang Health District in order to determine the prevalence of dysmenorrhea and associated factors among women at child bearing age.

Methods

a transversal community-based study was carried out from March to June 2018. Information regarding socio-demographic features, prevalence, factors associated with the dysmenorrhea and the effect of dysmenorrhea on daily activities were collected using structured questionnaire and data were analyzed using Epi Info version 7.1.3.3 Software.

Results

a total of 637 women aged 12 to 50 years were interviewed in the present study. The mean body mass index was 25.94 with an average weight of 66.41 kilogram. Fifty six point twenty percent (56.20%) of participants had dysmenorrhea. From all risks factors fund only the normal body mass index (OR = 3.08, P-value = 0.01) having a significant association with the occurrence of dysmenorrhea. Daily activities were affected in 73.25% of participants dysmenorrheic and those who had some episodes of dysmenorrhea.

Conclusion

the present study showed that more than a half of respondents were dysmenorrheic and several factors were associated with this pathology. This study also suggests that dysmenorrhea have a negative impact on the daily activities of women at child bearing age.

Anti-androgenic, anti-oxidant and anti-apoptotic effects of the aqueous and methanol extracts of Pterorhachis zenkeri (Meliaceae): Evidence from in vivo and in vitro studies

The aim of this study was to evaluate the effects of Pterorhachis zenkeri (Meliaceae) on sex organ growth in immature male rats and, oxidative stress and apoptosis markers in CCL-97 (R2C) Leydig cells. For the in vivo studies, 70 immature male Wistar rats (n = 10/group) were treated for 2 or 4 weeks with: distilled water (10 ml/kg, per os) plus soya oil (1 ml/kg, sc), bicalutamide (10 mg/kg, per os), aqueous or methanol extract of P. zenkeri (10 mg/kg or 62 mg/kg, per os) or testosterone propionate (3 mg/kg, sc). After each treatment period, body and sexual organ weights, plasmatic testosterone, total proteins and total cholesterol levels were measured. In the in vitro test, the effects of the methanol extract of P. zenkeri on cell viability, apoptosis, reactive oxygen species (ROS) production, intracellular calcium release and caspases 3/9 were assessed using CCL-97 Leydig cells. Pterorhachis zenkeri extracts decreased sex organ weights, plasmatic testosterone and protein levels in rats. In the in vitro studies, P. zenkeri inhibited apoptosis, ROS production, calcium release and caspase 3/9 activities. These results suggest that P. zenkeri has anti-androgenic, anti-oxidant and anti-apoptotic activities with methanol extract being the most active and could be an effective alternative for the management of androgen-related diseases.

The Ethanol Extract of Avocado (Persea americana Mill. (Lauraceae)) Seeds Successfully Induces Implant Regression and Restores Ovarian Dynamic in a Rat Model of Endometriosis

Endometriosis is an estrogen-dependent disease with conventional therapies which do not have desirable effectiveness and possess many side effects. Scientific evidences suggest that medicinal plants with antioxidant, anti-inflammatory, and/or antiproliferative properties are potential alternatives for the treatment of endometriosis. The ethanol extract of Persea americana Mill. (Lauraceae) seeds was found exhibiting antiproliferative properties in vitro and in vivo. This study therefore is aimed at investigating the effects of such an extract on an experimental model of endometriosis. Endometriosis was induced by grafting uterine fragments onto the peritoneum of female Wistar rats. After checking the success of the transplantation surgery, animals with endometriosis were orally treated with the ethanol extract of P. americana seeds at the doses of 12.5, 25, and 50 mg/kg. The positive control was treated with letrozole (10 mg/kg) while the negative control received the vehicle. Treatments lasted 7 days and animals were sacrificed thereafter. Endometrial implant volume was determined. Estradiol and progesterone levels were measured in serum samples and endometriosis lesions. The oxidative status of endometriosis lesions was evaluated. Histological analysis of endometriosis lesions, uterus, and ovaries was also performed. Results showed that the ethanol extract of P. americana seeds decreased endometrial implant volume (p < 0.001) and serum levels of estradiol and progesterone (p < 0.01). The levels of estradiol also decreased in endometriosis lesions at doses of 12.5 and 50 mg/kg (p < 0.001). Both malondialdehyde and glutathione levels increased in endometriosis lesions (p < 0.001). The ectopic endometrium height decreased and the number of antral follicles and corpora lutea (p < 0.05) increased while that of luteinized unruptured follicles decreased (p < 0.001). In conclusion, the ethanol extract of P. americana seeds displayed an antiendometriosis effect suggesting that it could be a potential alternative for the treatment of endometriosis.

Rubus apetalus (Rosaceae) improves spermatozoa characteristics, antioxidant enzymes and fertility potential in unilateral cryptorchid rats

BACKGROUND

Cryptorchidism (CPT) is an important cause of male infertility. Rubus apetalus is a medicinal plant with a powerful antioxidant potential. We investigated the effects of aqueous and methanolic extracts of R. apetalus on spermatozoa parameters, antioxidant enzymes and fertility potential of rats with experimental unilateral CPT.

METHOD

Normal (n = 15), sham-operated (n = 15) and cryptorchid rats (n = 80; distributed into 16 groups of 5 rats/group) were treated for 2, 4 or 8 weeks with either distilled water (10 ml/kg/day), vitamin E (75 mg/kg/day), aqueous or methanolic extract of R. apetalus (12 and 60 mg/kg). Sex organ weights, spermatozoa parameters, testicular proteins, sex hormones, fertility potential, morphometric characteristics of testis and oxidative stress markers were measured.

RESULTS

CPT significantly (p < 0.05-0.001) decreased testicular and epididymal weights, spermatozoa density, spermatozoa motility, spermatozoa normality, testicular proteins, LH, FSH and testosterone concentrations. In cryptorchid rats, peri-vascular fibrosis significantly increased (p < 0.001), while diameter of the seminiferous tube, germ cell thickness, gestation index and fertility index decreased when compared to control. Additionally, CPT induced oxidative stress by increasing lipid peroxidation and by reducing superoxide dismutase and catalase activities. These alterations were corrected by R. apetalus. For instance, a significantly increase (p < 0.05-0.001) in spermatozoa motility, normality, viability and density after 2, 4 and 8 weeks of treatment was noticed. R. apetalus also increased (p < 0.05-0.001) testicular proteins, gestation index (90-100%) and fertility index (90-100%), compared to the untreated cryptorchid rats.

CONCLUSION

R. apetalus boosts fertility potential in cryptorchid rats and could be considered as a promising alternative agent for the management of infertility associated with CPT.

Semen quality among men attending urology services in the Dschang Health District, west Cameroon: A retrospective study on 379 cases

Background

Infertility is a common condition affecting at least 15% of couples worldwide, and male factors are involved in about half of this prevalence rate. In Cameroon, about 20%-40% of couples are the victims. However, the sperm characteristics of infertile men are yet to be described in the health districts in Cameroon for better management of male infertility.

Objective

The present study was designed to assess the sperm profile and related sociodemographic factors of men attending the urology services at the Dschang Health District.

Materials and Methods

It consisted of a 10 yr retrospective study carried out in the Dschang Health District. The results of patients' semen analysis (SA) were computed using Epi Info software and expressed as qualitative and quantitative spermogram state as described by the clinician and sociodemographic features of those patients.

Results

Out of the 379 patients studied, 83.91% had abnormal spermogram. Patients older than 50 yr were the most affected when grouped into age categories. With regard to patient's profession, 52.51% had specified their profession and from that group, although farmers (9.31%) represented the lowest size category, they were the most affected with 94.74% having abnormal spermogram.

Conclusion

This study indicates that the sperm damage is the major cause of male infertility in the Dschang Health District. It also shows that farmers are the most affected category and it could be linked to the long-term exposure to pesticides. These results call for the assessment of the reproductive toxicity of locally used pesticides.

Colibri® insecticide induces male reproductive toxicity: alleviating effects of Lannea acida (Anacardiaceae) in rats

Background

Imidacloprid, a neonicotinoid insecticide, has been associated to severe reproductive toxicity in mammals. Although some preventive measures have been reported, curative strategies are yet to be explored. The present study was designed to investigate the alleviating effects of Lannea acida on the reproductive toxicity of colibri®, a commercial formulation of imidacloprid, in adult male rats.

Materials and methods

Seventy rats were orally administered with colibri® (22.5 mg/kg, 10 mL/kg) for 14 days and treated for other 14 or 28 days with either aqueous or methanol extracts of L. acida (170 or 340 mg/kg). Control animals were similarly treated with clomiphene citrate or vitamin E. Sexual organ weights, spermatozoa characteristics, sexual hormones, stress markers and testis histology were evaluated at the end of each treatment period.

Results

Colibri® exposition induced reproductive toxicity marked by a decrease in sex organ weights, spermatozoa count, motility and viability. Colibri® also decreased testosterone, luteinizing hormone, follicle stimulating hormone concentrations and increased testicular oxidative stress. Spermatozoa morphology and testis histology were also severely altered. Similar to clomiphene citrate and vitamin E, treatment with L. acida extracts significantly (p ≤ 0.05–0.001) reversed the above-mentioned damages, especially after 28 days of treatment with aqueous (340 mg/kg) and methanol (170 mg/kg) extracts.

Conclusion

Present results indicate that L. acida exerts curative effects against colibri®-induced male reproductive toxicity. These results justify the use of this plant as fertility enhancer and suggest that it could be an alternative in the management of pesticide-derived male infertility.

Aqueous and ethanol extracts of Dracaena arborea (Wild) Link (Dracaenaceae) alleviate reproductive complications of diabetes mellitus in rats

Reproductive dysfunction is one of the most prevalent diabetes complications. Draceana arborea is known to enhance sexual function in diabetic rats, but the underlying mechanisms have not been thoroughly elucidated. This study examined the effects of D. arborea on some reproductive complications of diabetes in rats. Aqueous and ethanol (500 and 100 mg/kg respectively) extracts of D. arborea, Sildenafil citrate (1.44 mg/kg), trimethylamine-N-oxide (TMAO, 20 mg/kg) and distilled water (10 ml/kg) were orally administered for 28 days to streptozotocin-induced diabetic rats. Glycaemia, body and reproductive organ masses, fertility parameters, total proteins, antioxidant enzymes activities, serum and testicular testosterone and the histology of the testes and epididymis were determined. Results revealed significant decreases in body and absolute and relative masses of testes, epididymis, seminal vesicles, prostate and vas deferens, fertility parameters, epididymal and testicular total proteins, serum and testicular testosterone levels as well as antioxidant enzymes activities. Interestingly, while having minor anti-hyperglycaemic effects, these abnormalities associated with testicular and epididymal alterations were alleviated by D. arborea especially the aqueous extract (500 mg/kg). These outcomes provided evidence of the androgenic properties of D. arborea in diabetic rats, which could be useful for a better management of sexual dysfunctions in diabetic patients.

Aphrodisiac property of aqueous and methanolic extracts of Raphia vinifera (Arecaceae) in sexually experienced male rats

Background

Raphia vinifera (Arecaceae) is a medicinal plant commonly used as a sexual enhancer.

Objective

To investigate the aphrodisiac potential of aqueous extract (AE) and methanolic extract (ME) of R. vinifera in sexually experienced male rats.

Materials and Methods

Thirty male Wistar rats were randomly distributed into six groups (5 rats per group) and administered for 14 days with distilled water (10 ml/kg), sildenafil citrate (1.44 mg/kg), and AE or ME of R. vinifera (100 or 500 mg/kg). The copulatory activity was tested on days 0, 7, and 14 using receptive females. Further, on day 14, rats were sacrificed and biochemical analyses (testosterone, total protein, and acid phosphatase) were performed.

Results

Sildenafil citrate significantly decreased the intromission latency (day 14, p = 0.04) and frequency (days 7 and 14, p = 0.03) but increased the mount frequency (day 14, p = 0.04), compared with control. Remarkably, R. vinifera enhanced the sexual activity by significantly decreasing the intromission latency (AE and ME, 500 mg/kg, day 14, p = 0.04) and increasing the mount frequency (AE and ME, 100 mg/kg, day 7, p = 0.02) compared with control. Moreover, R. vinifera improved plasmatic (AE, 100 mg/kg, p = 0.03; AE, 500 mg/kg, p = 0.001; ME, 100 mg/kg, p = 0.01) and testicular (AE, 100 mg/kg, p = 0.001; AE, 500 mg/kg, p = 0.01; ME, 100 mg/kg, p = 0.001; ME, 500 mg/kg, p = 0.01) testosterone levels as well as plasmatic total proteins concentration (ME, 500 mg/kg, p = 0.04).

Conclusion

These findings showed that R. vinifera possesses an aphrodisiac property which could further justify its folkloric use in traditional medicine as a sexual enhancer.

Sexual stimulant effects of the mixture of Mondia whitei, Dracaena arborea, and Bridelia ferruginea in normal and prediabetic male Wistar rats

Background We investigated the effects of a polyherbal formulation prepared from the extracts of Mondia whitei (Periplocaceae), Dracaena arborea (Dracaenaceae), and Bridelia ferruginea (Euphorbiaceae) (MDB) on the sexual behavior of normal rats (NR) and prediabetic rats (PR). Methods Male Wistar rats were administered with drinking fructose solution (21%) or tap water for 16 weeks. After induction of prediabetic status, NR (n = 30) and PR (n = 30) were randomly distributed into 10 groups of six animals each and orally treated with distilled water (10 mL/kg), sildenafil citrate (5 mg/kg), or MDB (50, 100, or 500 mg/kg) for 21 days. Sexual behavior parameters per series (S) of ejaculation were evaluated on days 1, 7, 14, and 21. Results Drinking fructose solution (21%) induced prediabetic status in rats, characterized by a significant (p < 0.01) increase in glycemia by 43.41% compared with the control group. MDB improved sexual performances of NR and PR by increasing the mount frequency (MF) and the intromission frequency (IF) as well as the number of rats capable of ejaculating. For instance, the MF and the IF were significantly increased in animals administered with MDB for 7 (50 mg/kg, S1 and S2), 14 (100 mg/kg, S3), or 21 days (100 or 500 mg/kg, S2). This increase was more pronounced on days 7 and 14 in NR and PR treated with sildenafil citrate or MDB extracts, respectively. Conclusions The mixture of MDB improved sexual activity in NR and PR. This result may further justify the traditional use of these plants as sexual performance enhancers.

Phyllanthus muellerianus (Euphorbiaceae) Restores Ovarian Functions in Letrozole-Induced Polycystic Ovarian Syndrome in Rats

Polycystic ovarian syndrome (PCOS) is one of the common causes or female infertility. Phyllanthus muellerianus (Euphorbiaceae) is a plant used to treat various ailments including frequent menstruation and anovulation. We investigated the effects of P. muellerianus extracts on estrus cyclicity, lipid profile, oxidative stress-related markers, sex hormones, and ovarian architecture in letrozole-induced PCOS in rats. After induction of PCOS using letrozole (1 mg/kg/day), normal (n=6), and PCOS (n=108; distributed into 18 groups of 6 animals/group) rats were treated orally for 7 or 14 days with distilled water (10 ml/kg/day), clomiphene citrate (2 mg/kg/day), metformin (500 mg/kg/day), and aqueous or methanolic extract of P. muellerianus (30, 60, and 120 mg/kg). Estrus cyclicity, body, and sexual organ (ovaries and uterus) weights, biochemical and histological parameters were measured. There were letrozole-induced PCOS characterized by irregular estrus cyclicity, elevated (p<0.05-0.01) glycaemia, ovarian weight, triglycerides, total cholesterol, LDL cholesterol, VLDL cholesterol, malondialdehyde, luteinizing hormone (LH), and testosterone concentrations, but there were low (p<0.05-0.001) HDL cholesterol, estradiol, progesterone, catalase, peroxidase, and superoxide dismutase levels, compared with control. PCOS rats had multiple cysts compared with control. These reproductive, biochemical, and structural alterations were alleviated by P. muellerianus extracts. For instance, P. muellerianus restored the estrus cyclicity with a remarkable effect after 14 days of treatment. Moreover, P. muellerianus significantly decreased (p<0.001) LH and testosterone (both extracts; 30, 60, and 120 mg/kg) levels, but increased (p<0.01) estradiol (aqueous extract; 60 mg/kg) concentration. Cystic follicles were also decreased after plant application. P. muellerianus alleviated reproductive, hormonal, and structural alterations in PCOS rats. This plant could be useful in the management/treatment of reproductive and metabolic disorders related to PCOS.

The aqueous and methanol extracts of Bambusa vulgaris (Poaceae) improve calcium and phosphorus levels, and bone microstructure in ovariectomized model of osteoporosis

Background Osteoporosis represents the most common metabolic bone disease. Bambusa vulgaris (Poaceae) is a plant with potential antiosteoporotic effects, due to its phytoestrogenic, antioxidative, and anti-inflammatory properties. This study was undertaken to evaluate the effects of aqueous and methanol extracts of B. vulgaris on osteoporosis in rats. Methods Adult female Wistar rats were randomly divided into normal (n = 6) and ovariectomized (n = 42) groups. Twelve weeks after ovariectomy, animals were treated for 4 weeks as follows: distilled water (10 mL/kg, per os (p.o.)), 17β-estradiol (10 μg/kg, intraperitoneal (i.p.)), soya oil (1 mL/kg, i.p.), aqueous or methanol extract of B. vulgaris (55 or 110 mg/kg, p.o.). All rats were weighed daily and sacrificed on day 29. Plasma was collected, and the uterus and femur were dissected out, weighed, and used for biochemical and histological measurements. Results In the untreated ovariectomized females, a non-significant (p > 0.05) increase in body weight and a significant decrease (p < 0.001) in the uterine and bone weights were recorded. Ovariectomy also significantly (p < 0.001) lowered the bone calcium and phosphorus concentrations, and deteriorated the microarchitecture of the femur. Interestingly, B. vulgaris extracts significantly (p < 0.001) improved the bone calcium concentration and femur microarchitecture (increase in trabecular bone density, reorganization of the trabecular network, and increase in bone marrow) with estrogenic-like effects compared to 17β-estradiol. Conclusion These results suggest that B. vulgaris is a potential therapeutic drug for the treatment of osteoporosis. The present findings further justify the ethno-medicinal claims of B. vulgaris.

Guibourtia tessmannii-induced fictive ejaculation in spinal male rat: involvement of D1, D2-like receptors

CONTEXT

Guibourtia tessmannii (Caesalpiniaceae) is a plant traditionally used as aphrodisiac. We previously reported the pro-ejaculatory effects of the aqueous and methanol extracts of G. tesmannii in spinal male rat. However, the mechanism underlying such effects has not been elucidated.

OBJECTIVE

This study characterizes the dopaminergic sub-type receptors involved in G. tesmannii-induced ejaculation in male Wistar rat.

MATERIALS AND METHODS

Urethane-anesthetized spinal male rats were intravenously treated with saline solution (1 mL/kg, control); dopamine (0.1 μmol/kg, reference); aqueous or methanol extracts of G. tesmannii (20 mg/kg) in the absence or presence of haloperidol (0.26 μmol/kg), a nonspecific dopaminergic receptor antagonist, Sch23390 (0.26 μmol/kg), a specific D1-like receptor antagonist or, sulpiride (0.26 μmol/kg), a specific D2-like receptor antagonist. Electromyography of the bulbospongiosus muscles and intraseminal pressure were recorded after urethral, penile and drug stimulations.

RESULTS

Urethral and penile stimulations, intravenous injection of dopamine or, aqueous and methanol extracts of G. tesmannii always triggered the expression of rhythmic contraction of the bulbospongiosus muscles with an average mean of 3.33 ± 0.43; 7.83 ± 0.85; 9.80 ± 0.86; 0.83 ± 0.54 and 2.67 ± 0.95 contractions, respectively. The intraseminal pressure was more expressed after urethral and penile stimulations (15.66 ± 1.58 and 13.60 ± 2.40 mmHg, respectively). In rats pretreated with haloperidol, Sch23390 or sulpiride, no ejaculation was recorded after intravenous injection of G. tesmannii extracts or dopamine.

DISCUSSION AND CONCLUSION

Guibourtia tesmannii-induced ejaculation requires the integrity of D1 and D2-like receptors. These findings further justify the ethno-medicinal claims of G. tesmannii as an aphrodisiac.

Androgenic effects of aqueous and methanolic extracts of Ficus asperifolia in male Wistar rats

BACKGROUND

Androgen deficiency is a clinical syndrome resulting from the inability of the testes to produce physiological levels of testosterone due to a disturbance occurring at one or more levels of the hypothalamic-pituitary-testicular axis. The present study was undertaken to evaluate the androgenic properties of aqueous and methanolic extracts of Ficus asperifolia on normal and castrated immature rats.

METHODS

Normal rats were treated either per os with aqueous or methanolic extract of Ficus asperifolia (100 mg/kg or 500 mg/kg b.w.), distilled water (10 ml/kg b.w.), 5% Tween 80 (10 ml/kg b.w.) or subcutaneously with testosterone propionate (0.5 mg/kg b.w.). Castrated rats were treated with plant extracts (100 mg/kg b.w. or 500 mg/kg b.w.) alone or with the co-administration of plant extracts and testosterone propionate (s.c., 0.5 mg/kg b.w.) or bicalutamide (2 mg/kg b.w. per os). Animals were treated once a day during four weeks. Body weight growth and relative sexual organ weights were recorded at the end of each treatment. Some biomedical parameters were measured in the plasma (proteins, cholesterol), testes (cholesterol) and epididymis (proteins).

RESULTS

In normal rats, Ficus asperifolia significantly (p < 0.05) increased the relative weights of the testes and all sexual-dependent organs whereas total testicular cholesterol concentration was significantly (p < 0.05) decreased. In castrated groups, treatment with Ficus asperifolia was followed by an increase in the sexual organ weights, epididymal protein and prostatic acid phosphatase concentrations. The co-administration of testosterone and plant extracts significantly (p < 0.05) increased the weight of accessory sexual organs and epididymal protein contents. In the presence of bicalutamide (an anti-androgen), the sexual stimulating activity of Ficus asperifolia was diminished with remarkable effects on vas deferens weight (p < 0.05), plasma (p < 0.01) and epididymal (p < 0.05) protein contents.

CONCLUSION

Ficus asperifolia possesses androgen-like activity through possible stimulation of cytoplasmic and/or nuclear receptors by the bioactive compounds found in its extracts.

Allanblackia floribunda Oliv.: An aphrodisiac plant with vasorelaxant properties

ETHNOPHARMACOLOGICAL RELEVANCE

Allanblackia floribunda Oliv. is one of the most commonly used medicinal plant in Cameroon. The stem bark of the plant is traditionally used for its aphrodisiac and antihypertensive properties.

AIM OF THE STUDY

To validate the traditional uses of Allanblackia floribunda stem bark ethanol extract through the evaluation of their aphrodisiac and vasorelaxant properties.

MATERIALS AND METHODS

The extract's ability to increase sexual desire and the frequencies of erection (mount), intromission and prolonged latency of ejaculation were studied on adult male rats. The vasodilator effect was investigated using isolated rat aorta rings. Tests were conducted using fractions obtained by reverse phase column-chromatography (CC), after the acquisition of the HPLC fingerprint of the ethanol extract, resulted the most active in previous studies.

RESULTS

The CC allowed the isolation of five fractions whose aphrodisiac and vasodilator activities were tested and compared with those of the whole extract. Four compounds were identified and characterized, three of them, Fukugiside, Morelloflavone and Volkensiflavone, are secondary metabolites known to be in Allanblackia floribunda; the fourth, Spicataside, is a biflavonoid glycoside known to be present in the genus Garcinia but never found neither in Allanblackia floribunda nor in Allanblackia genus. The crude ethanolic extract (CEE) induced a relaxation on aorta rings with EC₅₀=11±2μg/mL and Morelloflavone displayed a similar activity with EC₅₀=42±6μg/mL; for all the other compounds only the vasodilation % at the maximum concentration assessable (90μg/mL) was determined: 30±8 (Fukugiside), 24±6 (Spicataside), 33±4 (Morelloflavone+Volkensiflavone), 47±1 (Volkensiflavone). Regarding the activity on male sexual behaviour, only CEE and Fukugiside showed activity in the 9 parameters evaluated.

CONCLUSIONS

These results may support the traditional uses of Allanblackia floribunda as aphrodisiac plant with antihypertensive properties suggesting the phytocomplex as responsible for the claimed activity.

The expanded program on immunization service delivery in the Dschang health district, west region of Cameroon: a cross sectional survey

Background

Vaccination is the most effective intervention strategy, and the provision of vaccination at fixed posts and outreach posts is a backbone of a sustainable vaccination system in developing countries. Access to immunization services is still limited in Cameroon. Several health districts in the west region have recorded new epidemic outbreaks, including the occurrence of a wild polio virus epidemic outbreak in 2013. The aim of this study was to assess immunization service delivery in one of the largest health districts in the west region of Cameroon; the Dschang Health district.

Methods

It was a cross sectional study conducted in 2013, in 42 health facilities covering 18 health areas in the Dschang Health District. Data were collected with questionnaires administered to health personnel face to face and an observation grid was used to assess resources and tools. Data were entered and analyzed in Epi Info.

Results

A total of 42 health facilities were assessed and 77 health personnel were interviewed. Overall, 29 (69.0 %) health facilities organized one vaccination session monthly, 2 (4.8 %) organized an outreach within the last 3 months prior to the study, 15 (35.7 %) did not have a vaccination micro plan, 24 (32.9 %) health personnel had not been supervised for at least the last 6 months prior to the study, 7 (16.7 %) health facilities did not have a functional refrigerator, 1 (2.4 %) did not have a vaccine carrier, 23 (54.8 %) did not have a means of transport (vehicle or motorcycle) and 12 (28.6 %) did not have an EPI guideline. The knowledge of health personnel on vaccine and cold chain management, and on diseases of the EPI under epidemiological surveillance was found to be limited.

Conclusion

The frequency and strategic provision of immunization services in the Dschang Health district is inadequate. Resource availability for an adequate provision of immunization services is insufficient. The knowledge of health personnel on vaccine management, cold chain management and on diseases under surveillance by the EPI is limited.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-016-3429-7) contains supplementary material, which is available to authorized users.

High fat diet-induced estrus cycle disruption: effects of Ficus asperifolia

BACKGROUND

Ficus asperifolia (L) Hook. Ex Miq (Moraceae) fruits are used in Cameroonian traditional medicine to cure some cases of infertility in women. This study determines the mechanism of alleviating effect of the plant extracts on rat infertility induced by a high fat diet (HFD).

METHODS

Obesity was reached by feeding female rats with a HFD for 10 weeks. Vaginal smear was observed daily for 3 weeks after animals were obese. Then, 70 animals with abnormal estrus cyclicity were selected and partitioned into two sets of 35 animals. Each set was further divided into seven groups of five rats. These obese rats with disrupted estrus cyclicity were orally administered the aqueous and methanolic extracts (100 and 500 mg/kg), distilled water (10 mL/kg), 5% Tween 80 (10 mL/kg) or lutenyl (0.8 µg/kg) once a day for 1 week (set I) or 4 weeks (set II). Estrus cyclicity, body weight gain, hematocrit, lipid profile, ovarian, uterine and hepatic growth indices were determined at the end of each treatment.

RESULTS

HFD increased the body weight of the animals by 27% and disrupted the estrus cyclicity by 98.44%. Aqueous extract (100 mg/kg) of F. asperifolia given for 1 week corrected 40% of the irregular estrus cycle and this percentage increased to 80% as the treatment progressed to 4 weeks. F. asperifolia-treated obese rats (mostly with the aqueous extract at 100 mg/kg) showed a significant decrease (p<0.001) in the total plasma cholesterol and low density lipoprotein (LDL) cholesterol level and a significant increase (p<0.001) in high density lipoprotein (HDL) cholesterol. F. asperifolia has bioactive agents that may maintain conducive conditions for reproduction in obese female rats.

CONCLUSIONS

Our data support the anecdotal claims of F. asperifolia in folk medicine to cure some cases of infertility in women.

Cycloartanes from Oxyanthus pallidus and derivatives with analgesic activities

Background

The leaves of Oxyanthus pallidus Hiern (Rubiaceae) are extensively used in the west region of Cameroon as analgesic. These leaves are rich in cycloartanes, a subclass of triterpenes known to possess analgesic and anti-inflammatory properties. The present study aimed at evaluating the analgesic properties of three cycloartanes isolated from Oxyanthus pallidus leaves as well as their aglycones and acetylated derivatives.

Methods

Three cycloartanes OP₃, OP₅ and OP₆ obtained by successive chromatography of the crude methanol extract of the leaves were hydrolysed to yield respective aglycone AOP₁, AOP₂, AOP₃ and acetylated to HOP₁, HOP₂ and HOP₃ respectively. Formalin-induced pain model was used to evaluate the acute anti-nociceptive properties of these cycloartanes (5 mg/kg, p.o) in mice and to determine the structure-activity relationship. Acute (24 h) and chronic (10 days) anti-hyperalgesic and anti-inflammatory activities of OP₅ were evaluated at the doses of 2.5 and 5 mg/kg/day administered orally. OP₆ was also evaluated in acute experiments. The antioxidant and hepato-protective activities of OP₅ were evaluated at the end of the chronic treatment.

Results

The mixture and the individual isolated cycloartanes significantly inhibited both phases of formalin-induced pain with percentage inhibition ranging from 13 to 78 %. Acid hydrolysis did not significantly affect their antinociceptive activities while acetylation significantly reduced the effects of these compounds during the second phase of pain. OP₅ and OP₆ induced acute anti-hyperalgesic activity in formalin-induced mechanical hyperalgesia but not an anti-inflammatory effect. Repeated administration of OP₅ for 10 days did not induce any anti-hyperalgesic effect. The evaluation of in vivo antioxidant properties showed that OP₅ significantly reduced malondialdehyde and increased superoxide dismutase levels in liver without significantly affecting other oxidative stress and hepatotoxic parameters. Chronic administration of OP₅ did not cause gastric ulceration.

Conclusion

Cycloartanes isolated from Oxyanthus pallidus possess analgesic effects but lack anti-inflammatory activities. This analgesic effect especially on inflammatory pain may be due to the presence of hydroxyl group in front of the plane. OP₅ is devoid of ulcerogenic effect and possess antioxidant properties that might be of benefit to its analgesic properties.

Endothelium nitric oxide-independent vasorelaxant effects of the aqueous extract from Stephania abyssinica on the isolated rat thoracic aorta

BACKGROUND

Stephania abyssinica (Dillon & A. Rich) Walp (Menispermaceae) is a medicinal plant used in the west region of Cameroon to treat arterial hypertension. The present study evaluated the vasorelaxant effects of the aqueous (AESA) and methanol (MESA) extracts from the fresh leaves of S. abyssinica on aorta rings isolated from Wistar rats.

METHODS

Aorta rings with intact endothelium were contracted with KCl (60 mM) or phenylephrine (10-5 M) and exposed to cumulative concentrations of each extract, ranging from 10 to 1,000 µg/mL. The vasorelaxant effects of AESA were further evaluated in presence of Nω-nitro-L-arginine methyl ester (L-NAME, 10-4 M), tetraethylammonium (TEA, 5 µM), glibenclamide (5 µM), propranolol (5 µM), and the association glibenclamide-propranolol (AGP). In another set of experiments, the effect of AESA was evaluated on calcium-induced contraction in a hyperpotassic milieu.

RESULTS

AESA and MESA exhibited a concentration-dependent vasorelaxation on KCl-contracted aortic rings with respective EC50 of 160.10 and 346.50 µg/mL. AESA similarly relaxed aortic rings contracted with phenylephrine (EC50, 176.80 µg/mL). The vasorelaxant activity of AESA was not significantly affected by L-NAME but was markedly reduced by TEA, glibenclamide, propranolol, and AGP. AESA strongly inhibited the Ca2+-induced contraction by 95%.

CONCLUSIONS

These results support the use of S. abyssinica against arterial hypertension and suggest that the vasorelaxant effect of AESA is not mediated via the endothelium/nitric oxide pathway. AESA relaxant properties might be due to an inhibition of Ca2+ influx and/or the activation of ATP-sensitive K+ channels probably via the stimulation of β-adrenergic receptors.

Assessing the detection, reporting and investigation of adverse events in clinical trial protocols implemented in Cameroon: a documentary review of clinical trial protocols

BACKGROUND

International guidelines recommend ethical and scientific quality standards for managing and reporting adverse events occurring during clinical trials to competent research ethics committees and regulatory authorities. The purpose of this study was to determine whether clinical trial protocols in Cameroon are developed in line with national requirements and international guidelines as far as detecting, reporting and investigating of adverse events is concerned.

METHODS

It was a documentary review of all approved clinical trial protocols that were submitted at the Cameroon National Ethics Committee for evaluation from 1997 through 2012. Data were extracted using a preconceived and validated grid. Protocol review process targeted the title, abstract, objectives, methodology, resources, and the chapter on safety.

RESULTS

In total, 106 (4.9 %) clinical trial protocols were identified from 2173 protocols seen in the archive and 104 (4.8 %) included for review. Seventy six (73.1 %) trials did not include the surveillance of adverse events as part of their objective. A total of 91 (87.5 %) protocols did not budget for adverse event surveillance, 76 (73.1 %) did not have a data safety management board (DSMB), 11(10.6 %) included insurance for participants, 47 (45.2 %) did not include a case definition for serious adverse events, 33 (31.7 %) described procedures to detect adverse events, 33 (31.7 %) described procedure for reporting and 22 (21.2 %) described procedure for investigating adverse events.

DISCUSSIONS

Most clinical trial protocols in Cameroon are developed to focus on benefits and pay little attention to harms. The development of national guidelines can improve the surveillance of adverse events in clinical trial research conducted in Cameroon. Adverse events surveillance tools and a budget are critical for an adequate planning for adverse event surveillance when developing trial protocols.

CONCLUSION

Clinical trial protocols submitted in the Cameroon National Ethics Committee do not adequately plan to assess adverse events in clinical trial protocols. In order to improve on the safety of participants and marketed drug, there is a need to develop national guidelines for clinical trials by the government, and to improve evaluation procedures and monitoring of ongoing trials by the ethics committee.

In vitro anti-hyperglycemic and antioxidant properties of extracts from the stem bark of Ceiba pentandra

BACKGROUND

The goal of the study was to determine the antidiabetic mechanisms and the antioxidant effects of aqueous (decoction and maceration) and methanol extracts from the stem bark of Ceiba pentandra.

METHODS

These extracts were tested in vitro on glucose uptake by skeletal muscles and liver slices and on glucose release by liver slices. The antioxidant activities of C. pentandra extracts were investigated at concentrations ranging from 1 to 300 µg/mL on 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2)-induced hemolysis, H2O2-induced brain lipid peroxidation, hydroxyl (˙OH) radical as well as their reducing power.

RESULTS

The decoction similarly to insulin exhibited a significant glucose lowering activity. In a hyperglycemic milieu, it significantly increased glucose uptake by the liver by 56.57% and in the skeletal muscle by 94.19%. In a hypoglycemic milieu, it significantly reduced glucose release by the liver by 33.94%. The decoction, maceration and methanol extracts exhibited a significant radical scavenging activity on DPPH with respective EC50 of 87.84, 54.77 and 6.15 µg/mL versus 2.24 µg/mL observed with ascorbic acid. All the extracts showed a significant antioxidant effect on hydroxyl radical, against lipid peroxidation and H2O2-induced hemolysis. The decoction showed the greatest antihemolytic effect with a maximum inhibition of 77.57% at the concentration of 100 µg/mL. C. pentandra extracts also showed a concentration-dependent reducing power.

CONCLUSIONS

These results suggest that the antidiabetic effect of C. pentandra is due to its ability to increase glucose uptake and to reduce glucose release by target organs. The antioxidant properties of C. pentandra extracts are additional benefit for their antidiabetic effects.

Effects of Ficus asperifolia on normal rat estrus cyclicity

OBJECTIVE

To evaluate Ficus asperifolia (Moraceae) (F. asperifolia) effecting on regular estrus cycle of Wistar rats.

METHODS

Air-dried fruits of F. asperifolia were extracted using water. Prior to the test, vaginal smear was monitored daily for a 3-week period to select females with normal (regular) estrous cycle. Those with regular estrus cycle weighing between 150-170 g were randomized into three sets of 15 animals each. Each set was then divided into three groups: Group 1 (control) was orally administered with distilled water (10 mL/kg body weight) once a day for 1 week starting from the proestrus stage. Groups 2 and 3 were respectively treated with 100 and 500 mg/kg body weight of the plant aqueous extract. The two other sets of 15 animals each were similarly treated as the first set for 3 weeks and 6 weeks respectively. Estrus cycle pattern was monitored before and during plant extract application whereas lipid profile, ovary, uterus and liver growth indices were determined at the end of each treatment.

RESULTS

F. asperifolia did not disrupt (0%) the order of appearance of normal estrus cycle stages, namely, proestrus, estrus, metestrus and diestrus. Short-term treatment (1 week duration) exhibited high frequency of appearance of proestrus and estrus stages while mid- (3 weeks) and long-term (6 weeks) treatments revealed constancy in the frequency of all stages irrespective to animal groups. The plasma and organ lipid profile, as well as ovary, uterus and liver growth remained unchanged when compared to distilled water-treated animals. Following long-term administration of plant extract (6 weeks), no adverse effect was noticed.

CONCLUSIONS

Our data partially support the use of F. asperifolia in common medicine.

Ejaculatory activities of Allanblackia floribunda stem bark in spinal male rats

CONTEXT

Medicinal plants have become a great source of relief for more 70% of the population in developing countries where access to modern medicine is very limited. Some of these plants are used as aphrodisiac agents. The stem bark of Allanblackia floribunda Oliver (Clusiacea) has been used in Cameroon as an aphrodisiac.

OBJECTIVE

This study was designed to assess the effects of Allanblackia floribunda aqueous and ethanol extracts and their potential mechanism on fictive ejaculation in spinal male rats.

MATERIALS AND METHODS

Electromyographic activities of the bulbospongiosus muscles were recorded in 24 groups of spinal rats after intravenous administration of aqueous and ethanol extracts (2.5, 10, 20, 40 or 60 mg/kg) from the stem bark of A. floribunda in the presence or absence of dopamine (60 mg/kg). Furthermore, electromyographic activities of the bulbospongiosus muscles were recorded in five groups of spinal rats pre-treated orally during 8 d with extracts (150 and 300 mg/kg) in the presence of dopamine.

RESULTS

Sequential treatments of rats with extracts significantly decreased the occurrence of ejaculation induced by dopamine up to 88.94% inhibition. The oral pre-treatment with both extracts significantly decreased the ejaculation induced by dopamine with the highest inhibition of 89.79%.

DISCUSSION AND CONCLUSION

Two extracts of A. floribunda used in this study had inhibitory activities on ejaculation. The inhibitory effect of A. floribunda extracts on fictive ejaculation in rat may be directly mediated through dopaminergic pathways. Inhibition of ejaculation caused by these extracts could support its use in patients suffering from rapid ejaculation.

Na+/H+ exchanger 1 inhibition reverses manifestation of peripheral diabetic neuropathy in type 1 diabetic rats

Evidence for an important role for Na(+)/H(+) exchangers in diabetic complications is emerging. The aim of this study was to evaluate whether Na(+)/H(+) exchanger 1 inhibition reverses experimental peripheral diabetic neuropathy. Control and streptozotocin-diabetic rats were treated with the specific Na(+)/H(+) exchanger 1 inhibitor cariporide for 4 wk after 12 wk without treatment. Neuropathy end points included sciatic motor and sensory nerve conduction velocities, endoneurial nutritive blood flow, vascular reactivity of epineurial arterioles, thermal nociception, tactile allodynia, and intraepidermal nerve fiber density. Advanced glycation end product and markers of oxidative stress, including nitrated protein levels in sciatic nerve, were evaluated by Western blot. Rats with 12-wk duration of diabetes developed motor and sensory nerve conduction deficits, thermal hypoalgesia, tactile allodynia, and intraepidermal nerve fiber loss. All these changes, including impairment of nerve blood flow and vascular reactivity of epineurial arterioles, were partially reversed by 4 wk of cariporide treatment. Na(+)/H(+) exchanger 1 inhibition was also associated with reduction of diabetes-induced accumulation of advanced glycation endproduct, oxidative stress, and nitrated proteins in sciatic nerve. In conclusion, these findings support an important role for Na(+)/H(+) exchanger 1 in functional, structural, and biochemical manifestations of peripheral diabetic neuropathy and provide the rationale for development of Na(+)/H(+) exchanger 1 inhibitors for treatment of diabetic vascular and neural complications.

Dracaena arborea alleviates ultra-structural spermatogenic alterations in streptozotocin-induced diabetic rats

Background

Infertility is a common complication in diabetic men and experimental animals, mainly due to loss of germ cells by apoptotic cell death. The aim of this study was to evaluate the effects of aqueous and ethanol extracts of Dracaena arborea in streptozotocin-induced ultra-structural spermatogenic alterations in Wistar rats.

Methods

Diabetic animals were orally treated with Millipore water (10 ml/kg), sildenafil citrate (1.44 mg/kg) or Dracaena arborea aqueous (500 mg/kg) and ethanol (100 mg/kg) extracts for three weeks. A group of non diabetic rats received Millipore water (10 ml/kg) and served as healthy control group. Blood glucose was monitored at the beginning and the end of the study. One day after the last treatment, animals were sacrificed and the testes immediately removed were morphologically observed and prepared for electron microscopy analysis of spermatogenesis.

Results

Our results showed that Dracaena arborea was devoid of any anti-hyperglycemic activity. In the untreated diabetic rats, hyperglycemia severely damaged the testes morphology as well as the spermatogenic process as evidenced by the: thickness of basement membrane of the seminiferous tubule; mitochondria alteration; abnormal spermatocyte cells displaying polymorphous nuclei, cytoplasmic vacuolization and necrosis; and disorganization and degeneration of sperm germ cells. Administration of sildenafil citrate and Dracaena arborea extracts to the diabetic rats improved testes morphology and reversed, although not completely, the impairment of spermatogenesis; this alleviating effect was more pronounced in animals treated with the aqueous extract (500 mg/kg) of Dracaena arborea.

Conclusion

Dracaena arborea improves testes morphology and restores spermatogenesis in type 1 diabetic rats, without having major anti-hyperglycemic properties. These effects could be attributed to saponins, flavonoids, phenols and sterols revealed in this plant, which could be a useful component in the treatment of diabetes-induced testicular dysfunction.

Endoplasmic reticulum stress plays a key role in the pathogenesis of diabetic peripheral neuropathy

Endoplasmic reticulum stress resulting from abnormal folding of newly synthesized proteins impairs metabolism, transcriptional regulation, and gene expression, and it is a key mechanism of cell injury. Endoplasmic reticulum stress plays an important role in cardiovascular and neurodegenerative diseases, cancer, and diabetes. We evaluated the role for this phenomenon in diabetic peripheral neuropathy. Endoplasmic reticulum stress manifest in upregulation of multiple components of unfolded protein response was identified in neural tissues (sciatic nerve, spinal cord) of streptozotocin diabetic rats and mice. A chemical chaperone, trimethylamine oxide, administered for 12 weeks after induction of diabetes (110 mg·kg⁻¹·d⁻¹, a prevention paradigm) attenuated endoplasmic reticulum stress, peripheral nerve dysfunction, intraepidermal nerve fiber loss, and sciatic nerve and spinal cord oxidative-nitrative stress in streptozotocin diabetic rats. Similar effects on diabetes-induced endoplasmic reticulum stress and peripheral nerve dysfunction were observed with a structurally unrelated chemical chaperone, 4-phenylbutyric acid (100 mg·kg⁻¹·d⁻¹, intraperitoneal). CCAAT/enhancer-binding protein homologous protein (CHOP)(-/-) mice made diabetic with streptozotocin displayed less severe sciatic nerve oxidative-nitrative stress and peripheral neuropathy than the wild-type (C57Bl6/J) mice. Neither chemical chaperones nor CHOP gene deficiency reduced diabetic hyperglycemia. Our findings reveal an important role of endoplasmic reticulum stress in the development of diabetic peripheral neuropathy and identify a potential new therapeutic target.

Metanx alleviates multiple manifestations of peripheral neuropathy and increases intraepidermal nerve fiber density in Zucker diabetic fatty rats

Metanx is a product containing L-methylfolate, pyridoxal 5'-phosphate, and methylcobalamin for management of endothelial dysfunction. Metanx ingredients counteract endothelial nitric oxide synthase uncoupling and oxidative stress in vascular endothelium and peripheral nerve. This study evaluates Metanx on diabetic peripheral neuropathy in ZDF rats, a model of type 2 diabetes. Metanx was administered to 15-week-old ZDF and ZDF lean rats at either 4.87 mg ⋅ kg(-1) ⋅ day(-1) (a body weight-based equivalent of human dose) or 24.35 mg ⋅ kg(-1) ⋅ day(-1) by oral gavage two times a day for 4 weeks. Both doses alleviated hind limb digital sensory, but not sciatic motor, nerve conduction slowing and thermal and mechanical hypoalgesia in the absence of any reduction of hyperglycemia. Low-dose Metanx increased intraepidermal nerve fiber density but did not prevent morphometric changes in distal tibial nerve myelinated fibers. Metanx treatment counteracted endothelial nitric oxide synthase uncoupling, inducible nitric oxide synthase upregulation, and methylglyoxal-derived advanced glycation end product, nitrotyrosine, and nitrite/nitrate accumulation in the peripheral nerve. In conclusion, Metanx, at a body weight-based equivalent of human dose, increased intraepidermal nerve fiber density and improved multiple parameters of peripheral nerve function in ZDF rats. Clinical studies are needed to determine if Metanx finds use in management of diabetic peripheral neuropathy.

Triglyceride, nonesterified fatty acids, and prediabetic neuropathy: role for oxidative-nitrosative stress

Peripheral neuropathy develops in human subjects with prediabetes and metabolic syndrome before overt hyperglycemia. The contributions of impaired glucose tolerance and insulin signaling, hypertriglyceridemia and/or increased nonesterified fatty acids (NEFA), and hypercholesterolemia to this condition remain unknown. Niacin and its derivatives alleviate dyslipidemia with a minor effect on glucose homeostasis. This study evaluated the roles of impaired glucose tolerance versus dyslipidemia in prediabetic neuropathy using Zucker fatty (fa/fa) rats and the niacin derivative acipimox, as well as the interplay of hypertriglyceridemia, increased NEFA, and oxidative-nitrosative stress. Sixteen-week-old Zucker fatty rats with impaired glucose tolerance, obesity, hyperinsulinemia, hypertriglyceridemia, hypercholesterolemia, and increased NEFA displayed sensory nerve conduction velocity deficit, thermal and mechanical hypoalgesia, and tactile allodynia. Acipimox (100 mg kg(-1) day(-1), 4 weeks) reduced serum insulin, NEFA, and triglyceride concentrations without affecting glucose tolerance and hypercholesterolemia. It alleviated sensory nerve conduction velocity deficit and changes in behavioral measures of sensory function and corrected oxidative-nitrosative stress, but not impaired insulin signaling, in peripheral nerve. Elevated NEFA increased total and mitochondrial superoxide production and NAD(P)H oxidase activity in cultured human Schwann cells. In conclusion, hypertriglyceridemia and/or increased NEFA concentrations cause prediabetic neuropathy through oxidative-nitrosative stress. Lipid-lowering agents and antioxidants may find a use in the management of this condition.

Prediabetic nephropathy as an early consequence of the high-calorie/high-fat diet: relation to oxidative stress

This study evaluated early renal functional, structural, and biochemical changes in high-calorie/high-fat diet fed mice, a model of prediabetes and alimentary obesity. Male C57BL6/J mice were fed normal (11 kcal% fat) or high-fat (58 kcal% fat) diets for 16 wk. Renal changes were evaluated by histochemistry and immunohistochemistry, Western blot analysis, ELISA, enzymatic assays, and chemiluminometry. High-fat diet consumption led to increased body and kidney weights, impaired glucose tolerance, hyperinsulinemia, polyuria, a 2.7-fold increase in 24-h urinary albumin excretion, 20% increase in renal glomerular volume, 18% increase in renal collagen deposition, and 8% drop of glomerular podocytes. It also resulted in a 5.3-fold increase in urinary 8-isoprostane excretion and a 38% increase in renal cortex 4-hydroxynonenal adduct accumulation. 4-hydroxynonenal adduct level and immunoreactivity or Sirtuin 1 expression in renal medulla were not affected. Studies of potential mechanisms of the high-fat diet induced renal cortex oxidative injury revealed that whereas nicotinamide adenine dinucleotide phosphate reduced form oxidase activity only tended to increase, 12/15-lipoxygenase was significantly up-regulated, with approximately 12% increase in the enzyme protein expression and approximately 2-fold accumulation of 12(S)-hydroxyeicosatetraenoic acid, a marker of 12/15-lipoxygenase activity. Accumulation of periodic acid-Schiff -positive material, concentrations of TGF-β, sorbitol pathway intermediates, and expression of nephrin, CAAT/enhancer-binding protein homologous protein, phosphoeukaryotic initiation factor-α, and total eukaryotic initiation factor-α in the renal cortex were indistinguishable between experimental groups. Vascular endothelial growth factor concentrations were reduced in high-fat diet fed mice. In conclusion, systemic and renal cortex oxidative stress associated with 12/15-lipoxygenase overexpression and activation is an early phenomenon caused by high-calorie/high-fat diet consumption and a likely contributor to kidney disease associated with prediabetes and alimentary obesity.

Evaluation of In Vitro Uterotonic Activities of Fruit Extracts of Ficus asperifolia in Rats

The aim of the present study was to determine the uterotonic activities of Ficus asperifolia and investigate its mechanism. The effects of aqueous and methanol extracts of the dried fruits of F. asperifolia (0.05–1.60 mg mL⁻¹) were evaluated on estrogenized isolated rat uterus in the presence and absence of atropine (1.73–55.27 nM), pyrilamine maleate (1.25 × 10⁻³ to 40 × 10⁻³ M), indomethacin (0.06 × 10⁻⁵ to 2.00 × 10⁻⁵ M) or hexamethonium (0.66 × 10⁻⁴ to 21.43 × 10⁻⁴ M). Aqueous (EC₅₀, 0.36 mg mL⁻¹) and methanol (EC₅₀, 0.22 mg mL⁻¹) extracts as well as oxytocin (EC₅₀, 0.02 nM), acetylcholine (EC₅₀, 7.87 nM) and histamine (EC₅₀, 0.76 nM) evoked concentration-dependent contractions of the uterus. Atropine, pyrilamine maleate and indomethacin concentration dependently blocked the response of the uterus to acetylcholine (IC₅₀, 4.82 nM), histamine (IC₅₀, 2.49 nM) and oxytocin (IC₅₀, 0.07 nM), respectively, and to aqueous extract. Hexamethonium produced graded decreases in oxytocin-induced uterine contractions (IC₅₀, 0.37 μM), but did not prevent the contractile effects of the aqueous extract (IC₅₀, 9.88 μM). These results suggest that F. asperifolia-induced uterotonic effect is related to the release of prostaglandins and contraction of the myometrial cells through muscarinic, oxytocic and H₁ histamine receptors. These data further give added value to the ethnic use of F. asperifolia for its abortificient and contraceptive properties.