RANKL/OPG in primary cultures of osteoblasts from post-menopausal women. Differences between osteoporotic hip fractures and osteoarthritis

The OPG/RANKL/RANK system is important in the balance between bone formation and resorption.We used primary human osteoblasts (hOBs) cells to examine the impact of 17-β-estradiol (E2) or/and 1,25-dihydroxyvitamin D (1,25D) in OPG/RANKL system in 28 post-menopausal (PM) women; (a) with hip fracture (OP) or (b) with osteoarthritis (OA). The hOB from OP patients proliferated slower during the first stage, than the OA women (31.5 ± 2.6 and 21.4 ± 1.3 days, respectively, p < 0.05). The OP group secreted significantly higher OPG protein levels than the OA women (10.1 ± 2.6 and 4.4 ± 0.8 pmol/L, respectively, p < 0.05). The 1,25D and 1,25D+E2 induce an increase in RANKL and RANKL/OPG mRNA expression in OP patients above 200% (p < 0.05).HOBs from the osteoporotic hip initially proliferate slower but after reaching the first cellular confluence, the proliferation rate is equal in both groups. Furthermore, hOBs from hips with OP present a higher protein secretion of OPG, and higher RANKL and RANKL/OPG expression ratio in response to 1,25D and 1,25D+E2, than hOBs from OA women. All this could suggest that the greater bone loss that characterizes OP patients can be mediated due to differences in the secretion and expression of the RANKL/OPG system in response to different stimuli.     

IL-9 Induces CCL11 Expression via STAT3 Signalling in Human Airway Smooth Muscle Cells

Background

Previous findings support the concept that IL-9 may play a significant role in mediating both pro-inflammatory and changes in airway responsiveness that characterizes the atopic asthmatic state. We previously demonstrated that human airway smooth muscle (ASM) cells express a functional IL-9R that mediate CCL11 expression. However, the signaling pathway governing this effect is not well understood.

Methodology/Principal Findings

In this study, we showed that IL-9 mediated CCL11 expression in ASM cells does not rely on STAT6 or STAT5 but on STAT3 pathway. IL-9 induced rapid STAT3 activation in primary ASM cells that was not observed in case of STAT6 or STAT5. STAT3 binding to CCL11 promoter was also observed in vivo upon IL-9 stimulation of ASM cells. Disruption of STAT3 activity with SH2 domain binding inhibitory peptide results in significant reduction of IL-9 mediated CCL11 promoter activity. DN STAT3β over-expression in ASM cells, but not Ser 727 STAT3 or STAT6 DN, abolishes IL-9 mediated CCL11 promoter activity. Finally, STAT3 but not STAT6 silenced ASM cells showed significant reduction in IL-9 mediated CCL11 promoter activity and mRNA expression.

Conclusion/Significance

Taken together, our results indicate that IL-9 mediated CCL11 via STAT3 signalling pathway may play a crucial role in airway inflammatory responses.     

Photocontrol of bud burst involves gibberellin biosynthesis in Rosa sp

Light is a critical determinant of plant shape by controlling branching patterns and bud burst in many species. To gain insight into how light induces bud burst, we investigated whether its inductive effect in rose was related to gibberellin (GA) biosynthesis. In axillary buds of beheaded plants subject to light, the expression of two GA biosynthesis genes (RoGA20ox and RoGA3ox) was promptly and strongly induced, while that of a GA-catabolism genes (RoGA2ox) was reduced. By contrast, lower expression levels of these two GA biosynthesis genes were found in darkness, and correlated with a total inhibition of bud burst. This effect was dependent on both light intensity and quality. In in vitro cultured buds, the inductive effect of light on the growth of preformed leaves and SAM organogenic activity was inhibited by ancymidol and paclobutrazol, two effectors of GA biosynthesis. This effect was concentration-dependent, and negated by GA(3). However, GA(3) alone could not rescue bud burst in the dark. GA biosynthesis was also required for the expression and activity of a vacuolar invertase, and therefore for light-induced sugar metabolism within buds. These findings are evidence that GA biosynthesis contributes to the light effect on bud burst and lay the foundations of a better understanding of its exact role in plant branching.     

miRISC recruits decapping factors to miRNA targets to enhance their degradation

MicroRNA (miRNA)-induced silencing complexes (miRISCs) repress translation and promote degradation of miRNA targets. Target degradation occurs through the 5′-to-3′ messenger RNA (mRNA) decay pathway, wherein, after shortening of the mRNA poly(A) tail, the removal of the 5′ cap structure by decapping triggers irreversible decay of the mRNA body. Here, we demonstrate that miRISC enhances the association of the decapping activators DCP1, Me31B and HPat with deadenylated miRNA targets that accumulate when decapping is blocked. DCP1 and Me31B recruitment by miRISC occurs before the completion of deadenylation. Remarkably, miRISC recruits DCP1, Me31B and HPat to engineered miRNA targets transcribed by RNA polymerase III, which lack a cap structure, a protein-coding region and a poly(A) tail. Furthermore, miRISC can trigger decapping and the subsequent degradation of mRNA targets independently of ongoing deadenylation. Thus, miRISC increases the local concentration of the decapping machinery on miRNA targets to facilitate decapping and irreversibly shut down their translation.     

Comparative Metabolic Profiling of Two Contrasting Date Palm Genotypes Under Salinity

Since specific metabolites may be associated with salinity tolerance, this study aimed to decipher the salinity tolerance mechanism in date palm based on the information encoded by the metabolomic profiles of the salt-tolerant “Umsila” and salt-susceptible “Zabad” cultivars when grown under salinity conditions. Changes in the metabolomic profiles of the leaf and root tissues were determined using hydrophilic interaction liquid chromatography (HILIC) and reverse-phase liquid chromatography (RPLC) mass spectrometry. The global untargeted metabolomic analysis showed the presence of 4878 metabolites accumulated in leaf and root tissues of the date palm seedlings. Principal component analysis (PCA) revealed the presence of unique groups of metabolites for each treatment and tissue type. Pathway analysis showed the involvement of some of these metabolites in the biosynthesis of several types of membranous lipids and glycolipids molecules such as 18:0-lyso-phosphatidylethanolamine (lysoPE), and also the synthesis of cell-wall components such as 16-hydroxy hexadecanoic acid, which is an intermediate metabolite in cutin, suberin, and wax biosynthesis. Moreover, antioxidant flavonoids such as (+)-catechin and epicatechin, vitamins such as B₉, phytohormone-associated compounds such as dihydrozeatin-9-N-glucoside-O-glucoside, and osmolytes such as the sulfonic amino acid taurine were all significantly (p?≤?0.05, FWER?≤?0.05) altered in response to salinity in both cultivars. These results indicate that salinity tolerance in date palm involved a multi-dimensional mechanism, which includes the modification of the cell-wall and cellular membranes, the production of oxygen species scavengers, the adjustment of cellular osmotic pressure, and probably the alteration of the hormonal balance. The intracultivar metabolomic profile comparison strategy performed in this study represents an approach that may pave the road toward the identification of salinity tolerance mechanisms in date palm based on the final protein products.

     

The effect of salt concentration and pH on the heat resistance of Escherichia coli in tryptic soy broth

The effect of the acid and the osmotic stress on the heat resistance of Escherichia coli (EC1 and EC2) was studied at 63 degrees C in tryptic soy broth adjusted to various pHs (2.5, 4.5 and 6) and various NaCl concentrations (2, 4 and 8%). In the second study, the effect of pretreatment on thermotolerance of E. coli cells was determined. The heat resistance of both strains was low at pH 2.5, but strain EC1 was more resistant than strain EC2. On the contrary, the heat resistance increased with increasing the pH values. Addition of NaCl (2%) to TSB medium, was involved in the protection of cells against heat inactivation, this protective effect was, however, not observed by increasing the NaCl concentration up to 8%. The combined effect of the pH and NaCl on the thermal resistance of both strains was significantly lower at pH 2.5 and NaCl 8%, the number of viable cells decreased from approximately 10(8) CFU/ml to an undetectable number within 20 min for strain EC1 and 15 min for strain EC2, respectively. This study indicates that heat resistance of strain EC1 was enhanced after acid or thermal adaptation. Heat resistance of strain EC2 was, however, enhanced only after thermal adaptation. For both strains no relationship was found between salt adaptation and the ability to resist thermal stress.     

Direct gene transfer study and transgenic plant regeneration after electroporation into mesophyll protoplasts of <Emphasis Type="Italic">Pelargonium</Emphasis> <Emphasis Type="Italic">×</Emphasis> <Emphasis Type="Italic">hortorum</Emphasis>, ‘Panaché Sud’

Direct genetic transformation of mesophyll protoplasts was studied in Pelargonium × hortorum. Calcein and green-fluorescent protein (GFP) gene were used to set up the process. Electroporation (three electric pulses from a 33-μF capacitor in a 250-V cm⁻¹ electric field) was more efficient than PEG 6000 for membrane permeation, protoplast survival and cell division. Transient expression of GFP was detected in 33–36% of electroporated protoplasts after 2 days and further in colonies. A protoplast suspension conductivity of >1,500 μS cm⁻¹ allowed high colony formation and plant regeneration. Stable transformation was obtained using the plasmid FAJ3000 containing uidA and nptII genes. When selection (50 mg l⁻¹ kanamycin) was achieved 6 weeks after electroporation, regenerated shoots were able to grow and root on 100 mg l⁻¹ kanamycin. The maximum transformation efficiency was 4.5%, based on the number of colonies producing kanamycin-resistant rooted plants or 0.7% based on the number of cultured protoplasts. Polymerase chain reaction (PCR) analysis on in vitro micropropagated plants showed that 18 clones out of 20 contained the nptII gene, while the uidA gene was absent. These results were confirmed after PCR analyses of five glasshouse-acclimatized clones.     

Secular trend in height in Al Ain-United Arab Emirates

Correlation between cycles in human stature and those in economic variables is well established. A recent review of international trends in this area provided information from most parts of the world but none on Arabs in the Middle East or more specifically the gulf region.The United Arab Emirates experienced a transformation in economic and social life followed the discovery of oil in the late 1960s and the wealth that it generated. No data is available on human growth at this period of time because its population never had health services prior to the 1970s. A study on conventional cardiovascular risk factors in 2004-2005 included 817 randomly selected national adults (≥18 years) from both genders. The relationship between height and age in this study showed both men and women have increased in height with time demonstrating the secular change in height most likely a result of changing socioeconomic factors.