The Effects of Apricot Kernels and Pure Amygdalin on the Structural, Oxidative, and Inflammatory Characteristics of Rabbit Testicular Tissue.

BACKGROUND: Apricot kernels containing amygdalin (AMG) as the major cyanogenic glycoside are potentially useful as a complementary therapy for the management of several ailments including cancer. Nevertheless, little is known regarding the toxic and therapeutic doses of AMG, particularly in terms of male reproduction. Hence, this study evaluates selected qualitative characteristics of rabbit testicular tissue following in vivo administration of AMG or apricot kernels for 28 days. METHODS: The rabbits were randomly divided into five groups (Control, P1, P2, P3, P4). The Control received no AMG/apricot kernels while the experimental groups P1 and P2 received a daily intramuscular injection of amygdalin at a dose of 0.6 and 3.0 mg/kg of body weight (b.w.) for 28 days, respectively. P3 and P4 received a daily dose of 60 and 300 mg/kg b.w. of crushed apricot kernels mixed with feed for 28 days, respectively. Changes to the testicular structure were quantified morphometrically, while tissue lysates were subjected to the evaluation of reactive oxygen species (ROS) production, total antioxidant capacity, activities of antioxidant enzymes, and glutathione concentration. The extent of damage to the proteins and lipids was quantified as well. Levels of selected cytokines were determined by the enzyme-linked immunosorbent assay while a luminometric approach was used to assess the activity of caspases. RESULTS: Rabbits treated with 3.0 mg/kg b.w. AMG presented a significantly increased protein oxidation (p = 0.0118) accompanied by a depletion of superoxide dismutase (p = 0.0464), catalase (p = 0.0317), and glutathione peroxidase (p = 0.0002). Significantly increased levels of interleukin-1 beta (p = 0.0012), tumor necrosis factors alpha (p = 0.0159), caspase-3/7 (p = 0.0014), and caspase-9 (p = 0.0243) were also recorded in the experimental group P2 when compared to the Control. No effects were observed in the rabbits treated with apricot kernels at the oxidative, inflammatory, and histopathological levels. CONCLUSIONS: Apricot kernels did not induce toxicity in the testicular tissues of male rabbits, unlike pure AMG, which had a negative effect on male reproductive structures carried out through oxidative, inflammatory, and pro-apoptotic mechanisms.

Potential toxicity of cyanogenic glycoside amygdalin and bitter apricot seed in rabbits-Health status evaluation.

Amygdalin is one of the most studied secondary metabolites of Prunus genus. It is a cyanogenic glycoside which was initially obtained from the bitter almonds seeds and is a major component of the seeds of plants, such as apricots, almonds, peaches, apples and other rosaceous plants. The views of scientists on the use of amygdalin have been contradictory for many years, partly because toxicokinetics and metabolism of amygdalin still have not been adequately explored. The present in vivo study was designed to reveal whether pure amygdalin intramuscularly injected or apricot seeds oral consumption induce changes in overall health status of rabbit as a biological model. A total of 60 adult rabbits were randomly divided into five groups. The control group received no amygdalin while the two experimental groups E1 and E2 received a daily intramuscular injection of amygdalin at doses 0.6 and 3.0 mg/kg bw. The experimental groups E3 and E4 were fed crushed bitter apricot seeds (Prunus armeniaca L.), at doses 60 and 300 mg/kg bw, mixed with commercial feed for rabbits. Blood collection was carried out after 14 days. Biochemical, haematological and antioxidant enzymes activity analysis were performed and statistically evaluated. A short-term amygdalin administration had negligible impact on biochemical parameters-mainly level of urea, bilirubin, cholesterol. Haematological profile of rabbits was influenced very slightly-non-significant platelet count and platelet percentage increase, erythrocytes count and haemoglobin decrease. SOD activity of rabbits decreased significantly (p > 0.05) after apricot seeds consumption (102.3 U/ml) in comparison to control (117.4 U/ml). Differences might be connected to diverse metabolism by different administration routes and at the same time by the presence of other substances in apricot seeds (phytosterols, polyphenols, fatty acids). However, a short-term consumption had only slight effect on health status of rabbits and at recommended doses did not represent risk for their health.

Assessment of rabbit spermatozoa characteristics after amygdalin and apricot seeds exposure in vivo.

This study evaluates rabbit spermatozoa motility parameters after in vivo administration of amygdalin and apricot seeds during a 28-day period. Apricot seeds are potentially useful in human nutrition and amygdalin is the major cyanogenic glycoside present therein. The rabbits were randomly divided into the five groups (Ctrl-Control, P1, P2, P3, P4) with 4 males in each group. Control group received no amygdalin/apricot seeds while the experimental groups P1 and P2 received a daily intramuscular injection of amygdalin at a dose 0.6 and 3.0 mg/kg b.w. respectively during 28 days. P3 and P4 received a daily dose 60 and 300 mg/kg b.w. of crushed apricot seeds mixed with feed during 28 days, respectively. CASA system was used to evaluate for motility, progressive motility, curvilinear velocity, amplitude of lateral head displacement and beat cross frequency. Intramuscular application of amygdalin resulted in a significant time- and dose-dependent decrease of spermatozoa motility as well as progressive motility. On the other hand, oral consumption of apricot seeds had no significant effect either on the rabbit spermatozoa motility or progressive motility over the entire course of the study. The analysis of the other motion characteristics revealed a similar trend depicting a continuous, time- and dose-dependent decrease of all parameters following intramuscular AMG administration, with significant differences particularly for the dose 3.0 mg AMG/kg b.w. On the other hand, oral administration of apricot seeds had no significant impact on spermatozoa motility parameters. The present study suggests that short-term intramuscular application of amygdalin decreased rabbit spermatozoa motility in vivo. Whereas, consumption of apricot seeds did not induce any change in rabbit spermatozoa in vivo. Our findings suggest dose-dependent negative effect of pure amygdalin, but not apricot seeds on the rabbit spermatozoa parameters.