Two lathyrane diterpenoid stereoisomers containing an unusual trans-gem-dimethylcyclopropane from the seeds of Euphorbia lathyris

Two novel lathyrane-type diterpenoids, the Euphorbia factors L(2a) (1) and L(2b) (2), and their stereoisomer Euphorbia factor L(2) (3) were obtained from seeds of Euphorbia lathyris. Both Euphorbia factors L(2a) and L(2b) possess an unprecedented trans-gem-dimethylcyclopropane as structural feature. Also, the Euphorbia factor L(2a) is the first example of a lathyrane diterpenoid with an endocyclic 12(Z)-double bond. The structures of the molecules and their absolute configurations were elucidated by comprehensive spectroscopic analyses, Cu-Kα radiation X-ray diffraction, and comparison with calculated electronic circular dichroism (ECD) data. The Euphorbia factor L(2b) exhibited an inhibitory effect against U937 cell line with an IC(50) value of 0.87 μM

Identification and mRNA Expression of Heat Shock Proteins in the Mud Crab (Scylla paramamosain) in Response to Acute Nitrite Exposure

Heat shock proteins (HSPs) play an important role in protecting organisms against various stressors. Heat shock protein 40 (HSP40) is a class of the heat shock protein family and performs a function as co-chaperone of HSP70. In this study, an HSP40 gene from the mud crab Scylla paramamosain (SpHSP40) was identified and characterized. The full-length cDNA of SpHSP40 was 1904 bp, containing an open reading frame (ORF) of 1191 bp, a 5´UTR of 118 bp, and a 3´UTR of 595 bp. The deduced amino acid sequence of SpHSP40 contained all four classical HSP40 family signatures. Quantitative real-time PCR analysis revealed that SpHSP40 transcript was expressed in a wide range of tissues, while strong expression was observed in the hepatopancreas. In order to understand the response of heat shock proteins induced by nitrite exposure, expression levels of HSPs (SpHSP90, SpHSP70, SpHSP60 and SpHSP40) mRNA in the hepatopancreas and gills were investigated. Results show that HSPs (SpHSP90, SpHSP70, SpHSP60 and SpHSP40) were up-regulated displaying a time-dependent pattern in response to nitrite stress. All these results indicate that HSPs play an important role in mediating environmental stress in mud crabs

Identification and mRNA Expression of Antioxidant Enzyme Genes in the Mud Crab (Scylla paramamosain) in Response to Acute Ammonia and Nitrite Exposure

Thioredoxin reductase (TrxR) is a conserved protein that is involved in protecting organisms against various oxidative stresses. In this study, a thioredoxin reductase gene was cloned from the mud crab Scylla paramamosain (SpTrxR). The full-length cDNA of SpTrxR is comprised of 2724 bp with a 1791 bp open reading frame that encodes a putative protein of 596 amino acids. The deduced amino acid sequence of SpTrxR contains the typical TrxR domain. Quantitative real-time PCR analysis revealed that the SpTrxR mRNA was distributed abundantly in mud crabs, while strong expression was observed mainly in the gills. The expression of antioxidant enzyme genes (SpTrxR, SpTrx, SpSOD, and SpCAT) was measured using quantitative real-time PCR after acute ammonia and nitrite exposure. The results show that antioxidant enzyme genes (SpTrxR, SpTrx, SpSOD, and SpCAT) were modulated by acute ammonia and nitrite exposure. These results suggest that antioxidant enzyme genes play an important role in protecting organisms against oxidative stres