Association between dopamine receptor D2 Taq IA gene polymorphism (rs1800497) and personality traits.

Objective: This study aimed to find a potential association between the DRD2 Taq1A gene polymorphism (rs1800497 C32806T) and personality traits. Methods: In all, 249 youths were recruited for this study. The Short-form Revised Eysenck Personality Questionnaire was administered to assess personality traits. The participants were genotyped for the DRD2 Taq1A polymorphism using the polymerase chain reaction-restriction fragment length polymorphism method. Statistical analysis was carried out to find a possible association between the genotypes and aspects of personality traits assessed. Results: The frequencies of the A1 and A2 alleles in our sampled population were 215 (43.2%) and 283 (56.8%), while the frequencies of A1A1, A1A2, and A2A2 were 67 (26.9%), 81 (32.5%), and 101 (40.6%), respectively. The study population was not in Hardy-Weinberg equilibrium (χ2 = 17.64, p < 0.001). The A2 allele was significantly associated with extraversion. Although this allele was also associated with neuroticism, psychoticism, and lie, the association was not significant. Conclusion: The A2 allele of the DRD2 Taq1A polymorphism was found to be more associated with extraversion, as measured by the Short-form Revised Eysenck Personality Questionnaire.

Jatonik polyherbal mixture induced rat liver MMPT pore opening in normal Wistar rat: In vitro and in vivo studies.

Objective: To assess acute toxicity, the in vitro and in vivo effects of methanol and ethyl acetate extracts (JME and JEE) of Jatonik polyherbal mixture on some mitochondria-related parameters and their effect on the activity of some liver enzymes. Methods: Acute toxicity of JME and JEE was determined using Lorke's method. In vitro and in vivo opening of the mitochondrial membrane permeability transition pore (MMPT pore) was spectrophotometrically assayed. Production of malondialdehyde (MDA) as an index of lipid peroxidation and the activity of mitochondrial ATPase was evaluated in vitro and in vivo and the effect of JME and JEE on the activity of liver enzymes such as alkaline phosphatase (ALP), aspartate and alanine aminotransferase (AST and ALT) and gamma-glutamyl transferase (GGT) was also investigated. Results: JME had an LD50 of 3 808 mg/kg b.w whereas JEE had an LD50 greater than 5 000 mg/kg b.w. of rats. After the rats have been fed with both extracts, a photomicrograph of a piece of liver tissue showed no apparent symptoms of toxicity. From the in vitro and in vivo studies, both extracts prompted intact mitochondria to open their MMPT pores. When compared to the control, lipid peroxide product release and ATPase activity were significantly increased (P < 0.05) in vitro and in vivo. The activities of AST, ALT, and GGT were all reduced at 50 mg/kg when treated with JME, but the activity of AST was considerably enhanced when treated with JEE (P < 0.05). The results revealed that both JME and JEE of the Jatonik polyherbal mixture had low toxicity, profound MMPTpore induction, and enhanced ATPase activity, but an increased MDA production. Conclusion: Jatonik extracts may be a promising target for drug development in diseases where there is dysregulation of apoptosis, however, further studies are needed to better clarify the molecular mechanism involved in these phenomena.

Stigmasterol isolated from the chloroform fraction of Adenopus breviflorus Benth fruit induces mitochondrial-dependent apoptosis in rat liver.

OBJECTIVES: Decoction of Adenopus breviflorus fruit is used in folkloric medicine for treating dysmenorrhea and gonorrhea. Phytochemicals from A. breviflorus may be potent in inducing mitochondrial-dependent apoptosis via the opening of the mitochondrial permeability transition (MPT) pore. Therefore, this study investigated the in vitro effects of stigmasterol isolated from the chloroform fraction of A. breviflorus (CFAB) and also the increasing concentration of CFAB on the opening of rat liver mitochondrial permeability transition (MPT) pore. METHODS: Fractionation of CFAB on column chromatography yielded a needle-like crystal which structure was elucidated by standard spectroscopic techniques. The effects of stigmasterol and CFAB on MPT pore opening were assayed spectrophotometrically. Also, the effect of CFAB on mitochondrial ATPase (mATPase) activity and cytochrome c (Cyt c) release were determined. RESULTS: Stigmasterol isolated from CFAB induced MPT pore opening significantly (p<0.05) when compared with the control. Similarly, CFAB significantly (p<0.05) induced MPT pore opening in rat liver mitochondria in a concentration-dependent manner in the presence and absence of the triggering agent - calcium ion. Furthermore, the increasing concentration of CFAB significantly (p<0.05) stimulated mitochondrial ATPase (mATPase) activity and Cyt c release in a concentration-dependent manner. CONCLUSIONS: The study showed that stigmasterol isolated from the chloroform fraction of A. breviflorus is a potent inducer of mitochondrial-dependent apoptosis. Also, the study further revealed that CFAB possesses potent bioactive compounds which can induce the mitochondrial-dependent apoptosis through the opening of the mitochondrial permeability transition pore, activation of mitochondrial ATPase (mATPase) activity and cytochrome c release.