A new heterocyclic compound from Cyathula officinalis Kuan

Effects of indole derivatives from Purpureocillium lilacinum in controlling tobacco mosaic virus

There are various types of compounds studied and applied for plant disease management, and some of them are environment friendly and suitable in organic production. An example is indole-3-carboxaldehyde (A1) and indole-3-carboxylic acid (A2) derived from Purpureocillium lilacinum H1463, which have shown a strong activity in the control of tobacco mosaic virus (TMV). In this study, the effects of these compounds were studied on suppressing TMV and corresponding mechanism. Both A1 and A2 exhibited strong anti-TMV activities in vitro and in vivo. They fractured TMV virions and forced the fractured particles agglomerated. A1 and A2 also induced immune responses or resistance of tobacco to TMV infection, including expressing hypersensitive reaction (HR), increasing defense-related enzymes and overexpressing pathogenesis-related (PR) proteins. The upregulation of salicylic acid (SA) biosynthesis genes PAL, ICS, and PBS3 confirmed that SA served as a defense-related signal molecule. Therefore, indole derivatives have a potential for activating defense of tobacco against TMV and other pathogens and can be used for disease control.

Trewioidesine A, an unsaturated fatty acid from rhizomes of Alchornea trewioides, shows synergy with NGF in inducing differentiation of pheochromocytoma PC12 cells

A new unsaturated fatty acid trewioidesine A (1), together with seven known compounds (2 - 8) were isolated from the rhizomes of Alchornea trewioides (Benth.) Muell. Arg. Their structures were established on the basis of extensive spectroscopic data interpretation (1 D and 2 D NMR, and HRESIMS). The absolute configuration of 1 was determined by electronic circular dichroism (ECD) calculations, confirming as trewioidesine A. The functionality of isolated compounds was tested in cultured PC12 cells, a cell line from rat pheochromocytoma. Trewioidesine A was the one showing robust activity in inducing neuronal differentiation: the induction was synergized when co-applied with nerve growth factor (NGF). In addition, a neurofilament 200 (NF200) promoter-luciferase (pNF200-Luc) reporter was used to evaluate the differentiating ability in the transfected PC12 cells for the isolated compounds. Trewioidesine A exhibited a strong NF200 promoter activation, and application of trewioidesine A with low dose of NGF significantly induced the promoter activity over 50%.

Characterization of Nine Compounds Isolated from the Acid Hydrolysate of Lonicera fulvotomentosa Hsu et S. C. Cheng and Evaluation of Their In Vitro Activity towards HIV Protease

In this study, we isolated nine compounds from the acid hydrolysate of the flower buds of Lonicera fulvotomentosa Hsu et S. C. Cheng and characterized their chemical structures using ¹H-NMR, ¹³C-NMR, and electron ionization mass spectroscopy (EI-MS). These compounds were identified as β-sitosterol (1), 5,5′-dibutoxy-2,2′-bifuran (2), nonacosane-10-ol (3), ethyl (3β)-3,23-dihydroxyolean-12-en-28-oate (4), oleanolic acid (5), ethyl caffeate (6), caffeic acid (7), isovanillin (8), and hederagenin (9), with 4 as a new triterpene compound. Inhibitory activity against human immunodeficiency virus (HIV) protease was also evaluated for the compounds, and only ethyl caffeate, caffeic acid, and isovanillin (6, 7, and 8) exhibited inhibitory effects, with IC₅₀ values of 1.0 μM, 1.5 μM, and 3.5 μM, respectively. Molecular docking with energy minimization and subsequent molecular dynamic (MD) simulation showed that ethyl caffeate and caffeic acid bound to the active site of HIV protease, while isovanillin drifted out from the active site and dissociated into bulk water during MD simulations, and most of the binding residues of HIV protease have been previously identified for HIV protease inhibitors. These results suggest that caffeic acid derivatives may possess inhibitory activities towards HIV protease other than previously reported inhibitory activities against HIV integrase, and thus ethyl caffeate and caffeic acid could be used as lead compounds in developing potential HIV protease inhibitors, and possibly even dual-function inhibitors against HIV.

Radix Cyathula officinalis Kuan inhibits arterial remodeling in spontaneously hypertensive rats

There is still no resolution for arterial remodeling related with hypertension, though hypertension treatment has access to a number of pharmacological agents. The present study aimed at investigating the prevention of Cyathula officinalis Kuan's roots (C. officinalis Kuan) against in arterial remodeling in vitro. Spontaneously hypertensive rats (SHRs) were intragastrically administered 3, 6 or 12 g/kg C. officinalis Kuan or normal saline or enalapril (2.5 mg/kg) once a day for 8 weeks. Hematoxylin and eosin were used to measure blood pressure and stain carotid and arota. The serum concentration of nitric oxide (NO) was measured by NO assay kit (nitrate reductase method). The endothelin-1 transcriptional level, endothelial NO synthase of endothelium as well as angiotensin II receptor type 1 (AT1R) of aorta and carotid was tested by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and the protein level in aorta was also measured by western blotting. The blood pressure in SHR+enalapril, SHR+3 g/kg, SHR+6 g/kg and SHR+12 g/kg C. officinalis Kuan groups was significantly decreased at 4, 6 and 8 weeks post-treatment compared with SHR group. Different doses of C. officinalis Kuan and enalapril treatment showed aortic wall thinness and strengthened NO serum level, but made no impact on the transcriptional level of AT1R in aorta or endothelial NO synthase in carotid. It is suggested by such results that therapy by C. officinalis Kuan is able to fight against arterial remodeling, thus may provide a new means to treat arterial remodeling caused by hypertension.

Chemical Constituents of Cordyceps cicadae

One new bifuran derivative (1), together with fourteen known compounds, were isolated from Cordyceps cicadae X. Q. Shing. The known compounds included nine nucleosides, uracil (2), uridine (3), 2′-deoxyuridine (4), 2′-deoxyinosine (5), guanosine (6), 2′-deoxyguanosine (7), thymidine (8), adenosine (9), and 2′-deoxyadenosine (10); three amino acids tryptophan (11), phenylalanine (12), and tyrosine (13); and two dopamine analogues N-acetylnoradrenaline (14) and its dimer, trans–2-(3′,4′-dihydroxyphenyl)-3-acetylamino-7-( N-acetyl-2″-amino-ethylene)-1,4-benzodioxane (15). Their structures were decisively elucidated by spectroscopic analysis, including 1D and 2D NMR techniques.