Table 1.
Effects of L-Carnitine in vivo on male reproductive function.
| Aims of the Study | Period, Dosing, Route of Administration | Model | Main Results | References |
|---|---|---|---|---|
| Examine whether the detrimental effects of long-term copper consumption on sperm quality and testis function of Wistar albino rats could be prevented by LC therapy | 30 days; 200 mg/kg CuSO4 50 and 100 mg/kg LC; oral administration |
3-month-old Wistar rats | Revitalization of sperm quality (motility, viability, number); Restoration of histological alterations (germ cell depletion, sloughing of germ cells, vacuolization, and degeneration); Rejuvenation of spermatogenesis. |
M. Khushboo et al., 2017 [93] |
| Study the protective effect of LC on Sertoli testis cells from the damage of chemotherapy | 5 days; 100 mg/kg LC intraperitoneally administration |
Testis Sertoli cells from adult male mice | Recovery of the sperm count and sperm motility; Higher expressions of occluding and GDNF; Lower expression of TGF-β3. |
Y. Cao et al., 2017 [38] |
| Evaluate the effect of carnitine supplementation of semen extender on fertility parameters of frozen-thawed buffalo sperm | 2.5 and 7.5 mM carnitine | Cryopreserved Buffalo semen | Increased ATP generation; Modulated ROS production. |
V. Longobardi et al., 2017 [96] |
| Evaluated whether some spermatic qualitative parameters could be ameliorated by carnitine treatment in adult rats exposed to doxorubicin | A single dose of LC (250 mg/kg body weight) | Pre-pubertal male Wistar rats | Increase in intact acrosome integrity; Decreased MDA and nitrite concentration; Increased fertility and implantation rate; Decreased spermatozoa with damaged DNA. |
R. Cabral et al., 2017 [35] |
| Investigate the protective effect of LC and L-arginine on semen quality, OS parameters, and testis cell energy after busulfan treatment | single I.P. injection of busulfan; 1 mL of L-arginine daily by oral gavage; 1 mL of LC by oral gavages |
Adult male Wistar rats | Improved sperm morphology, motility, velocity, and count; Increased MDA and ATP. |
Abd-Elrazek et al., 2017 [98] |
| Investigate the effects of dietary LC on semen quality, seminal antioxidant activity, and their implications for fertility in aged roosters | 12 weeks; 50 and 150 mg/kg body weight/day of LC |
Aged roosters | Increased sperm quality; Increased plasma concentration of testosterone; Increased seminal MDA concentration, CAT, and GSH-PX activity. |
Elokil et al., 2019 [37] |
| Investigate the possible protective role of Se and LC against the adverse effects induced by cadmium | 30 days; LC at a dose of 10 mg/kg |
Mature adult male albino mice | Increased CAT, GR, SOD, and GST activities; Less histopathological abnormalities; Less DNA damage. |
Alharthi et al., 2020 [33] |
| Investigate the possible effect of LC on the mechanisms of reproductive toxicity induced by chronic lead acetate treatment | 40 days by oral gavage; 50 mg/kg of lead acetate; 100 mg/kg of LC |
Male Wistar rats | Reduced testicular OS; Improved sperm parameters; Elevated serum FSH, LH, and testosterone. |
Abdel-Emam et al., 2021 [95] |
| Evaluate the underlying mechanism of the ameliorative effects of LC | 30 days; diet supplemented with 1.5% cholesterol + LC 150 mg/kg given orally |
Premature albino male rats | Histological protection for spermatogenic layers; Better concentration of sperm; Reduced sperm abnormalities. |
Karam et al., 2022 [94] |
Abbreviations: LC—L-Carnitine; CuSO4—Copper(II) sulfate; GDNF—Glial-derived neurotrophic factor; TGF-β3—Transforming growth factor-β3; ROS—Reactive Oxygen Species; MDA—malondialdehyde; CAT—catalase; GSH-PX—Glutathione peroxidase; GR—Glutathione reductase; SOD—superoxide dismutase; GST—Glutathione S-Transferase; OS—oxidative stress; FSH—Follicle-Stimulating Hormone; LH—Luteinizing Hormone.