Discussion on Improvement of Toxicological Pathology Study

Toxicological pathology plays a key role in drug safety assessment. To enhance the research level of toxicological pathology, the following studies should be carried out urgently: setting up a standard operation procedure (SOP) for toxicological pathology assessment; emphasizing on immunotoxicology evaluation; adopting a new experiment model of replacement, featuring high speed and reliability; introducing new techniques and new models in toxicological mechanism research; and establishing a new appraisal system to screen innovative drug and rapid and high precision methods for early security assessment, detection and measurement.     

In vitro dopaminergic neuroprotective and in vivo antiparkinsonian-like effects of Δ3,2-hydroxybakuchiol isolated from Psoralea corylifolia (L.)

Cocktail recipes containing Psoralea corylifolia seeds (PCS) are used to empirically treat Parkinson disease. A PCS isolate Δ³,2-hydroxybakuchiol (BU) can inhibit dopamine uptake in dopamine transporter (DAT) transfected Chinese hamster ovary (CHO) cells, and dopamine reuptake blockade may provide an alternative approach for ameliorating parkinsonism. Here, we assessed the potential dopaminergic neuroprotective, and antiparkinsonian-like activity of BU. BU sample size was increased by using a scale-up extraction paradigm. Pharmacologically, BU significantly protected SK-N-SH cells from 1-methyl-4-phenylpyridinium (MPP⁺) insult, produced striking inhibitory actions on dopamine/norepinephrine uptake and WIN35,428 binding in synaptosomes on in vivo administration, and significantly preventing poor performance on rotarod and dopaminergic loss in substantia nigra in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mice. BU acts by protecting dopaminergic neurons from MPP⁺ injury and preventing against MPTP-induced behavioral and histological lesions in the Parkinson’s disease (PD) model, possibly by inhibiting monoamine transporters. These findings suggest that BU could be meaningful in PD treatment. Received 14 January 2009; received after revision 22 February 2009; accepted 10 March 2009     

Studies on introduction of arrowhead proteinase inhibitor gene intoN. tobacco protoplasts

The Arrowhead Proteinase Inhibitor (API) gene was introduced into the protoplasts of mesophyll cells ofN. tobacco by PEG-mediated. The transformed protoplasts underging differentiation of callus and regeneration of plantlet have been growing into transgenic plants. Restriction endonuclease analysis of products amplificated by PCR indicates the existence of the API gene in the transformed plantlet. The extract of the leaves from the transformed plants shows trypsin inhibitory activity, which indicates the expression on the introduced API gene and the transformed plants can accumulate the inhibitor. However, the variation of the inhibitory activity of the transformed plants reveals the importance of the integration site of the API gene in the genome. Wang Xin: born in Dec. 1965. Master of science. Present address