RNA-Seq Dissects Incomplete Activation of Phytoalexin Biosynthesis by the Soybean Transcription Factors GmMYB29A2 and GmNAC42-1.

Glyceollins, isoflavonoid-derived antimicrobial metabolites, are the major phytoalexins in soybean (Glycine max). They play essential roles in providing resistance to the soil-borne pathogen Phytophthora sojae and have unconventional anticancer and neuroprotective activities that render them desirable for pharmaceutical development. Our previous studies revealed that the transcription factors GmMYB29A2 and GmNAC42-1 have essential roles in activating glyceollin biosynthesis, yet each cannot activate the transcription of all biosynthesis genes in the absence of a pathogen elicitor treatment. Here, we report that co-overexpressing both transcription factors is also insufficient to activate glyceollin biosynthesis. To understand this insufficiency, we compared the transcriptome profiles of hairy roots overexpressing each transcription factor with glyceollin-synthesizing roots treated with wall glucan elicitor (WGE) from P. sojae. GmMYB29A2 upregulated most of the WGE-regulated genes that encode enzymatic steps spanning from primary metabolism to the last step of glyceollin biosynthesis. By contrast, GmNAC42-1 upregulated glyceollin biosynthesis genes only when overexpressed in the presence of WGE treatment. This is consistent with our recent discovery that, in the absence of WGE, GmNAC42-1 is bound by GmJAZ1 proteins that inhibit its transactivation activity. WGE, and not GmMYB29A2 or GmNAC42-1, upregulated the heat shock family gene GmHSF6-1, the homolog of Arabidopsis HSFB2a that directly activated the transcription of several glyceollin biosynthesis genes. Our results provide important insights into what biosynthesis genes will need to be upregulated to activate the entire glyceollin biosynthetic pathway.

Synthesis of ranolazine derivatives containing the (1S,4S)-2,5-diazabicyclo[2.2.1]heptane moiety and their evaluation as vasodilating agents.

Two diazabicyclic analogues of ranolazine, (S,S,S)-5 and (S,S,R)-5, and their epimeric mixture were synthesized. Furthermore, their vasomotor effects on rat aorta rings precontracted with phenylephrine were analyzed. These compounds showed vasodilating effects significantly greater than ranolazine. The vasodilating activities of these analogues have two components, one that depends on the endothelium, due to the release of NO, and another one due to a direct effect on the vascular smooth muscle. The compounds [(S,S,S)(S,S,R)]-5 and (S,S,R)-5 induce, in a manner similar to ranolazine, the release of a prostanoid from the cyclooxygenase pathway, whose vasoconstrictor effect is masked by the predominant vasodilation induced by these compounds.

Effects of ranolazine on vasomotor responses of rat aortic rings.

BACKGROUND AND AIMS: Ranolazine is a piperazine derivative that was approved in 2006 for the treatment of chronic stable angina. Compared with first-line drugs currently used to treat angina, beneficial effects of ranolazine occur without changing hemodynamic parameters such as heart rate and blood pressure. In the present study the effects of ranolazine on vasomotor responses of rat aortic rings were examined. METHODS: Pharmacological evaluation was performed by analyzing the vasomotor responses of ranolazine on aortic rings of adult male Wistar rats precontracted with phenylephrine (10(-5) M). In each experiment we used a pair of rings (with and without endothelium) from the same aorta and superfused in the same bath. RESULTS: Ranolazine (10(-6)-10(-4) M) induced a concentration-dependent relaxation of phenylephrine-precontracted rings. The relaxation was only partially dependent on the presence of the endothelium (56.78 ± 6.81% in rings with endothelium and 47.88 ± 4.70% in rings without endothelium). In rings with endothelium, L-NAME induced a shift to the right of the concentration-response curve to ranolazine. Blocking the cyclooxygenase pathway induced a leftward shift of the concentration relaxation curve to ranolazine in both types of rings and increased the ranolazine-induced relaxation in rings without endothelium. CONCLUSIONS: Ranolazine has a vasodilatory effect that is predominantly endothelium-independent. The synthesis/release of nitric oxide by the endothelium may, however, contribute to its relaxing action. These effects of ranolazine may contribute to its beneficial effects in patients with stable angina.

Chemoenzymatic synthesis and cannabinoid activity of a new diazabicyclic amide of phenylacetylricinoleic acid.

Endocannabinoids (eCBs) are endogenous neuromodulators of synaptic transmission. Their dysfunction may cause debilitating disorders of diverse clinical manifestation. For example, drug addiction, lack of sex desire, eating disorders, such as anorexia or bulimia and dyssomnias. eCBs also participate in the regulation of core temperature and pain perception. In this context, it is important to recognize the utility of cannabinoid receptor 1 (CB1R) agonists, natural as Delta(9)-tetrahydrocannabinol (THC) or synthetic as Nabilone as useful drugs to alleviate this kind of patients' suffering. Therefore, we have developed a new drug, (R,Z)-18-((1S,4S)-5-methyl-2,5-diazabicyclo[2.2.1]heptan-2-yl)-18-oxooctadec-9-en-7-yl phenylacetate (PhAR-DBH-Me), that appears to bind and activate the CB1R. This diazabicyclic amide was synthesized from phenylacetylricinoleic acid and (1S,4S)-2,5-diazabicyclo[2.2.1]heptane. To test its cannabinergic properties we evaluated its effects on core temperature, pain perception, and the sleep-waking cycle of rats. Results indicate that 20 and 40mg/kg of PhAR-DBH-Me readily reduced core temperature and increased pain perception threshold. In addition, 20mg/kg increased REM sleep in otherwise normal rats. All these effects were prevented or attenuated by AM251, a CB1R antagonist. Place preference conditioning studies indicated that this molecule does not produce rewarding effects. These results strongly support that PhAR-DBH-Me possesses cannabinoid activity without the reinforcement effects.