Objective: This study aimed to determine anti-depressant effect of α-pinene on gonadectomized-related behavior in male rats. Materials and Methods: Thirty adult male Wistar rats were assigned to 5 experimental groups. In the control group, surgeries were identical but testes were not clamped, ligated or excised. In the sham control, surgeries were identical with no treatment. In the imipramine group, rats were administered with imipramine (15 mg/kg) followed by castration for 2 weeks. In groups 4 and 5, following castration, rats were i.p. injected with 𝛼-pinene (0.5 and 1 mg/kg) for 2 weeks, respectively. Following recovery, forced swimming test (FST), tail suspension test (TST), and open field test (OFT) were performed and serum levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activity were determined. Results: According to the data, immobility time significantly increased following castration compared to control group (p<0.05). Administration of the imipramine significantly decreased immobility time compared to control group (p<0.05). Treatment with 𝛼-pinene (0.5 and 1 mg/kg) significantly decreased immobility time in comparison with sham control group (p<0.05). Number of crossings in the OFT significantly diminished following castration and treatment with 𝛼-pinene (0.5 and 1 mg/kg) increased number of crossings in the OFT compared to sham control group (P<0.05). Serum MDA significantly increased while SOD, GPX and CAT decreased following castration compared to the control group (p<0.05). Administration of the 𝛼-pinene (0.5 and 1 mg/kg) significantly improved serum MDA, SOD, GPX and CAT production compared to the sham rat (p<0.05). Conclusion: These results suggested that 𝛼-pinene has anti-depressant and antioxidant effects in gonadectomized-related behavior in male rats

Tyrosinase is the key enzyme in melanin synthesis. Therefore, many Tyrosinase inhibitors have been tested in cosmetics and pharmaceuticals. The aim of this study was to compare the anti-Tyrosinase potential of Gallic acid and α-Pinene. The initial analysis was conducted using molecular docking methods. Then, laboratory experiments were performed using mushroom Tyrosinase, with catechol as the substrate and Kojic acid as the standard inhibitor of the enzyme. The antioxidant activity of Gallic acid and α-Pinene was evaluated using DPPH radicals. Docking scores showed that Gallic acid has a strong binding affinity towards Tyrosinase (ΔG = -6.33 Kcal/mol) forming an H-bond with Met 280 and a pi-pi stacking with His 263. α-Pinene could only bind to the active pocket via hydrophobic interactions, resulting in a lower binding affinity (ΔG = ˗3.89 Kcal/mol). Gallic acid showed the highest inhibitory effect (IC50 = 0.130 mg/mL), whereas α-Pinene showed a lower inhibitory capacity (IC50 = 0.392 mg/mL). The types of inhibition were competitive inhibition for Kojic acid and uncompetitive inhibition for Gallic acid. In the DPPH radical scavenging test, EC50 value for Gallic acid and α-Pinene was 0.269 mg/mL and 251.2 mg/mL, respectively. Both in silico and laboratory results were nearly identical. While α- Pinene is not as powerful an inhibitor of Tyrosinase as Gallic acid is, its effect will be increased perhaps by increasing its concentration. The anti-oxidant potential of Gallic acid is significantly higher than that of α-Pinene, so from this point of view also Gallic acid is more harmless and applicable with a higher degree of safeness.

Background: Parturition depression is an important physiological problem, and several attempts have been made to ascertain this physiological phenomenon. Natural monoterpenes like α-pinene have numerous beneficial properties, but no studies have been done on their antidepressant potential in postpartum animals.Objectives: This study aimed to determine the effects of prenatal administration of α-pinene on the antidepressant-like behavior of mice following delivery. Methods: Pregnant female mice were randomly assigned into four groups. In the control group, the animals were injected with saline on their 5, 8, 11, 14, and 17 gestation days (GD). In groups 2 to 4, pregnant female mice were injected with α-pinene (0.1, 0.5, and 1 mg/kg, respectively) at GD 5, 8, 11, 14, and 17. On day 2 postpartum, open field test (OFT), rotarod, forced swimming test (FST), and tail suspension test (TST) were used to evaluate the antidepressant activity of α-pinene in mice. Also, serum samples were taken to determine the antioxidant activity.Results: According to the results, α-pinene (0.5 and 1 mg/kg) significantly increased activity in OFT and staying on the rotarod (P≤0.05). Also, α-pinene (0.5 and 1 mg/kg) diminished immobility time (s) in TST and FST on postpartum mice (P≤0.05). α-pinene (0.5 and 1 mg/kg) decreased malondialdehyde while increased glutathione peroxidase, superoxide dismutase, and total antioxidant status levels in postpartum mice as compared with the control group (P≤0.05).Conclusion: It seems that prenatal administration of the α-pinene can alleviate postpartum depression via its antioxidant property in mice.

Background: Research shows that α-Pinene interacts with the opioidergic system. Objectives: This study aims to examine the toxicity and the effects of α-Pinene on morphine tolerance and dependence in mice. Methods: Guidelines No. 423 and No. 407 were used to investigate acute and sub-chronic toxicity, respectively. For sub-chronic toxicity analysis, the animals were sacrificed on day 28, and blood and tissue samples were collected. After inducing morphine tolerance or dependence, in both phases, animals received i. p. vehicle, diazepam (5 mg/kg), and α-Pinene (3. 125, 6. 25, and 12. 5 mg/kg). Withdrawal signs were recorded for 30 minutes. Results: Only the acute dose of α-Pinene showed mortality in animals, but mild lesions were seen in the brain, liver, and kidneys in the mice receiving its subchronic dose. Moreover, ALT, AST, ALP, and TG levels increased (P < 0. 05) in female mice. Besides, 6. 25 and 12. 5 mg/kg (P < 0. 001) of α-Pinene and only its high dose (12. 5 mg/kg) (P < 0. 001) reduced the number of jumps in the tolerance and dependence phases, respectively. Diarrhea (P < 0. 001), writhing (P < 0. 001), rearing, and climbing (P < 0. 05 and P < 0. 001, respectively) behaviors decreased in the tolerance phase, and grooming, climbing, and teeth chattering declined in the dependence phase (P < 0. 001). Conclusions: The LD50 of α-Pinene was lower than 2000 mg/kg, but its subchronic dose caused mild tissue toxicities and biochemical changes. Moreover, α-Pinene decreased morphine tolerance and dependence and possibly was useful for the treatment of opioid dependence after complimentary trials.