Isolation, characterization and expression analysis of a leaf-specific phosphoenolpyruvate carboxylase gene in Oryza sativa.

Suppression subtractive hybridization was carried out to enrich gene fragments over-expressed in rice leaves by subtraction to rice roots, from which two identical cDNA fragments were identified to encode putative phosphoenolpyruvate carboxylase. Then the corresponding full-length cDNA (Osppc) is isolated by RT-PCR and sequenced, which indicates an open reading frame of 2895bp is contained. Its deduced protein is encoded in 10 exons and shows high similarity to many other plant PEPCs. Comparing with maize and bacterial PEPCs, it is revealed that OSPPC shares many conserved domains and active sites that responsible for the structure, activity and regulation of this enzyme. Phylogenetic analysis demonstrates that OSPPC is grouped with C3 form PEPCs of wheat, maize and sorghum, which is consistent with the classification of rice. And a putative promoter element is predicted with DOF binding box, CAAT box and TATA box in the 5'-flanking sequence of Osppc gene. Moreover, Quantitative RT-PCR analyses are performed in hybrid rice and its parents, which show that Osppc is specifically expressed in leaf including leaf vein and sheath.     

Utility of Dexrazoxane for the Attenuation of Epirubicin-Induced Genetic Alterations in Mouse Germ Cells

Dexrazoxane has been approved to treat anthracycline-induced cardiomyopathy and extravasation. However, the effect of dexrazoxane on epirubicin-induced genetic alterations in germ cells has not yet been reported. Thus, the aim of this study was to determine whether dexrazoxane modulates epirubicin-induced genetic damage in the germ cells of male mice. Our results show that dexrazoxane was not genotoxic at the tested doses. Furthermore, it protected mouse germ cells against epirubicin-induced genetic alterations as detected by the reduction in disomic and diploid sperm, spermatogonial chromosomal aberrations, and abnormal sperm heads. The attenuating effect of dexrazoxane was greater at higher dose, indicating a dose-dependent effect. Moreover, sperm motility and count were ameliorated by dexrazoxane pretreatment. Epirubicin induced marked biochemical changes characteristic of oxidative DNA damage including elevated 8-hydroxy-2ʹ-deoxyguanosine levels and reduction in reduced glutathione. Pretreatment of mice with dexrazoxane before epirubicin challenge restored these altered endpoints. We conclude that dexrazoxane may efficiently mitigate the epirubicin insult in male germ cells, and prevent the enhanced risk of abnormal reproductive outcomes and associated health risks. Thus, pretreating patients with dexrazoxane prior to epirubicin may efficiently preserve not only sperm quality but also prevent the transmission of genetic damage to future generations.     

Use of biochemical markers to monitor changes in bone turnover in cynomolgus monkeys

The ovariectomized old cynomolgus monkey is a recognized model of human osteoporosis, and the same species can be used for the assessment of the efficacy and potential toxicity of agents intended to prevent or treat osteoporosis. Several assays have been developed that can measure the same biochemical markers of bone turnover as are used in human patients for the diagnosis and treatment follow-up of bone-related diseases, including osteoporosis. The aim of the present study was to describe the results obtained with these assays in normal control monkeys, their variations with age and sex, and their sensitivity in monitoring the bone turnover induced by ovariectomy in old skeletally mature cynomolgus monkeys. Seven old cynomolgus monkeys were bilaterally ovariectomized and 13 age-matched monkeys were sham-operated. Bone mineral density and biochemical markers were measured before and at regular intervals after surgery for up to 20 months. Total alkaline phosphatase (total ALP), bone-specific alkaline phosphatase isoenzyme (bone ALP) and osteocalcin (OC) were highly correlated to the decrease in bone mineral density (BMD) induced by ovariectomy. Deoxypyridinoline (DPD) measured by enzyme-linked immunoassay was insensitive to the bone resorption induced by ovariectomy, but cross-linked N-telopeptide (NTX-I) was higher in ovariectomized monkeys than in control monkeys. These results demonstrate that reliable biochemical parameters are available to adequately monitor and provide insight into osteoclastic bone resorption and osteoblastic bone formation, the two components of bone turnover in this animal model, and can thus be used to assess the efficacy and toxicity of potential therapeutic agents.     

Rare trisubstituted sesquiterpenes daucanes from the wild Daucus carota

Phytochemical and biological investigation of the roots of the wild Daucus carota ssp. carota afforded three new and four known compounds, including four sesquiterpenes daucane esters (1-3 [new], and 4), one polyacetylene (5), one sesquiterpene coumarin (6), and sitosterol glucoside. The structures of the new compounds were determined by comprehensive NMR studies, including DEPT, COSY, NOESY, HMQC and HMBC analyses. Based on an agar diffusion assay, 1, 2 and 4-6 were screened and found to contain a range of low antibacterial activities against four gram positive (Staphylococcus aureus, Streptomyces scabies, Bacillus subtilus, Bacillus cereus) and two gram negative species (Pseudomonas aeruginosa, Escherichia coli) as well as antifungal against Fusarium oxysporum and Aspergillus niger using cup agar diffusion assay.     

Clinical and Biochemical Correlates of Serum L-Ergothioneine Concentrations in Community-Dwelling Middle-Aged and Older Adults

Background

Despite the increasing interest towards the biological role of L-ergothioneine, little is known about the serum concentrations of this unusual aminothiol in older adults. We addressed this issue in a representative sample of community-dwelling middle-aged and older adults.

Methods

Body mass index, estimated glomerular filtration rate, serum concentrations of L-ergothioneine, taurine, homocysteine, cysteine, glutathione, cysteinylglycine, and glutamylcysteine were evaluated in 439 subjects (age 55–85 years) randomly selected from the Hunter Community Study.

Results

Median L-ergothioneine concentration in the entire cohort was 1.01 IQR 0.78–1.33 µmol/L. Concentrations were not affected by gender (P = 0.41) or by presence of chronic medical conditions (P = 0.15). By considering only healthy subjects, we defined a reference interval for L-ergothioneine serum concentrations from 0.36 (90% CI 0.31–0.44) to 3.08 (90% CI 2.45–3.76) µmol/L. Using stepwise multiple linear regression analysis L-ergothioneine was negatively correlated with age (rpartial = −0.15; P = 0.0018) and with glutamylcysteine concentrations (rpartial = −0.13; P = 0.0063).

Conclusions

A thorough analysis of serum L-ergothioneine concentrations was performed in a large group of community-dwelling middle-aged and older adults. Reference intervals were established. Age and glutamylcysteine were independently negatively associated with L-ergothioneine serum concentration.     

Pharmacological blockage of serotonin biosynthesis and circadian changes in oxaliplatin toxicity in rats

This study investigates if the serotoninergic system plays a role in chronotoxic effects of the anticancer agent oxaliplatin (l-OHP). Four groups of female rats (120 in total) synchronized with light-dark (12 h:12 h) were treated with: (i) saline, (ii) para-chlorophenylalanine (pCPA, an inhibitor of serotonin biosynthesis: 300 mg/kg/d, i.p. for two consecutive days), (iii) l-OHP (23 mg/kg, i.v.) at three different dosing times, or (iv) both pCPA and l-OHP. The results show pCPA (ii) obliterates the circadian rhythm in plasma ACTH but not in corticosterone or leukocytes, and (iii) l-OHP exerts circadian time-dependent toxic effects (body weight loss, leukopenia, and intestinal lesions) with greatest toxicity coinciding with treatment at the end of the nocturnal activity span (P < 0.05). In rats whose serotonin biosynthesis was blocked (iv), the circadian rhythms in the toxic effects of l-OHP and in ACTH were obliterated, while the rhythms in corticosterone and leukocytes persisted.