Abstract:
Infertility and sexual dysfunction exert psychological tolls on humans. This is characterised by
anxiety and debilitating feeling of inadequacy. Hence, use of aphrodisiacs and sex enhancing
drugs is common among people experiencing infertility. Sphenocentrum jollyanum root is widely
used for its aphrodisiac effect in folkloric medicine. However, there is dearth of information on
its mechanism of action on erectile dysfunction. This study was carried out to investigate the
spermatogenic and erectogenic activities of ethanol extract of Sphenocentrum jollyanum root in
rats and rabbits.
Sphenocentrum jollyanum root was harvested from Oniganbari via Ibadan and authenticated at
Forestry Research Institute Nigeria (FHI No. 106994). The dry root powder was macerated in
ethanol and the filtrate was evaporated to dryness in a water bath heated at 40ºC. The
phytochemical constituents of the extract were identified using the Gas chromatography Mass
spectrometry (GC-MS). Spermatogenic activities were determined in 35 male Wistar rats (180-
210 g) divided into seven groups (n=5) and treated orally thus: distilled water (0.5 mL/kg),
extract (300, 600 and 1000 mg/kg) for 56 days and extract (300, 600 and 1000 mg/kg) for 56
days +28 days recovery. Sperm profile was analysed by microscopy; testicular Glutathione
Peroxidase (GPx) and Superoxide Dismutase (SOD) activities by spectrophotometry. Mating
behaviour was evaluated on 40 Flemish rabbits (3.0-3.5 kg) and were treated orally for five days
thus: control (0.5 mL/kg, distilled water), extract (600 mg/kg), paroxetine (10 mg/kg), extract paroxetine (600 mg/kg), linoleic acid (0.03 mg/kg), linoleic acid-paroxetine (0.03 mg/kg),
sildenafil citrate (0.50 mg/kg), and sildenafil citrate-paroxetine (0.50 mg/kg). In vitro contractile
activities of extract were assessed in strips of rabbit corpus cavernosa (CC) pre-contracted with
10-7M Phenylephrine followed by introduction of blockers among which were;Nifedipine (10-
4M), Verapamil (10-4M), L-NAME (10-4M) and Indomethacin (10-4M) before treatment with
graded doses of Sodium nitropusside SNP (10-9
-10-5M), Acetylcholine ACh (10-9
-10-5M) or
extract (0.1-3.2 mg/mL). Data were analysed using ANOVA at α0.05.
Thirty-four chemical constituents were identified in the extract and linoleic acid was the most
abundant (73.5%). Sperm motility (93.0±1.2%), livability (97.2±0.6%) and count (193.50±15.25
million/mL) increased significantly in the 1000 mg/kg extract treated relative to control
(83.0±2.3%; 89.0±2.8%; 145.50 ± 12.25 million/mL) respectively. Testicular GPx (U/L) and
iii
SOD (U/mL) activities increased in 300 (268.3±13.57 and 1.92±0.13), 600 (338.2±14.69 and
1.64±0.05) and 1000 (393.6±18.12 and 1.49±0.28) mg/kg extract compared with control
(193.6±10.74 and 0.47±0.05). Increased activities were however reversed after recovery. The
extract reduced mount latency by 98.0%, while intromission frequency was increased by 150.0%
in paroxetine-treated rabbits. Significant contractile inhibition was produced by extract
(33.3±2.4%), ACH (42.8±2.3%) and SNP (52.8±1.6%) in corpus cavernosa strips of normal
rabbits. Maximal contraction of CC strips was reduced by extract to11.3±1.5% and 14.6±1.1% in
the presence of nifedipine (42.8±2.1%) and Verapamil (22.0±1.5%), respectively. Relaxation
response of CC to extract increased by 228.2% and 143.1% in the presence of Indomethacin and
L-NAME in strips of rabbits pretreated with paroxetine.
The ethanol extract of Sphenocentrum jollyanum root improved spermatogenic profile, increased
antioxidant activities and ameliorated paroxetine-induced erectile dysfunction. These actions
may be linked to linoleic acid.
