Effect of allelopathic compounds produced by Cistus ladanifer on germination of 20 Mediterranean taxa

In order to analyze the extent to which allelopathic action of Cistus ladanifer may influence the successional progression towards Mediterranean sub-climacic shrublands and the geographical distribution of other species, the inhibitory effect of Cistus ladanifer extracts on the germination of 20 Mediterranean species was analyzed. Five of the species tested were characteristic of maquis sub-climacic shrublands: Arbutus unedo, Adenocarpus argyrophyllus, Phillyrea angustifolia, Phillyrea latifolia, and Rhamnus alaternus. Tests were also carried out on 6 Cistaceae species in order to evaluate the auto-toxicity rate of allelopathic extracts: Halimium umbellatum subsp. viscosum, Halimium ocymoides, Cistus ladanifer, Cistus salvifolius, Cistus monspeliensis, and Cistus populifolius. Nine herbaceous species sharing the natural habitat with C. ladanifer were also examined. Results confirmed a clear inhibitory and delaying effect of aqueous C. ladanifer-leaf extracts on the germination of P. angustifolia, P. latifolia, R. alaternus, H. ocymoides, C. populifolius, Erysimum lagascae, Brassica barrelieri, Silene tridentata, and Moricandia moricandioides. Assays with soil collected below the canopy of the C. ladanifer community showed more pronounced inhibitory effect on sub-climacic shrub species than the aqueous extracts. In contrast, the opposite pattern was detected when analyzing the allelopathic effect of natural soil on Cistaceae and herbaceous species. Allelopathic compounds produced by C. ladanifer showed little auto-toxicity. The inhibitory effect of phytotoxic compounds accumulated in the jaral soil upon germination of A. unedo, B.␣barrelieri, and M. moricandioides was eliminated by heating soil at 150 °C for 10 min. Phenolic compounds (i.e. ferulic, p-hydroxybenzoic, vanillic, p-coumaric, and caffeic acids) and terpenes (i.e. α and β-pinene) with allelopathic documented effect were detected in the aqueous extracts and soil samples used in the analyses. We suggest that the allelopathic effect of C. ladanifer may influence the composition and structure of Mediterranean communities where the species is present, since it hinders the establishment of some sub-climacic species and may reduce the area occupied by numerous herbaceous species.     

CO2 limitation induces specific redox-dependent protein phosphorylation in Chlamydomonas reinhardtii

Acclimation of the green alga Chlamydomonas reinhardtii to limiting environmental CO2 induced specific protein phosphorylation at the surface of photosynthetic thylakoid membranes. Four phosphopeptides were identified and sequenced by nanospray quadrupole TOF MS from the cells acclimating to limiting CO2. One phosphopeptide originated from a protein that has not been annotated. We found that this unknown expressed protein (UEP) was encoded in the genome of C. reinhardtii. Three other phosphorylated peptides belonged to Lci5 protein encoded by the low-CO2-inducible gene 5 (lci5). The phosphorylation sites were mapped in the tandem repeats of Lci5 ensuring phosphorylation of four serine and three threonine residues in the protein. Immunoblotting with Lci5-specific antibodies revealed that Lci5 was localized in chloroplast and confined to the stromal side of the thylakoid membranes. Phosphorylation of Lci5 and UEP occurred strictly at limiting CO2; it required reduction of electron carriers in the thylakoid membrane, but was not induced by light. Both proteins were phosphorylated in the low-CO2-exposed algal mutant deficient in the light-activated protein kinase Stt7. Phosphorylation of previously unknown basic proteins UEP and Lci5 by specific redox-dependent protein kinase(s) in the photosynthetic membranes reveals the early response of green algae to limitation in the environmental inorganic carbon.     

Prepro-orexin and feeding-related peptide receptor expression in dehydration-induced anorexia

Food-restricted animals present metabolic adaptations that facilitate food-seeking behavior and decelerate energy utilization by reducing the hypothalamus–pituitary–thyroid (HPT) axis function. Stress by dehydration induces an anorexic behavior in rats, loss of weight and reduced food intake when compared to ad libitum fed animals, however these alterations are accompanied by HPT axis changes such as increased serum thyrotropin levels and enhanced expression of thyrotropin-releasing hormone (TRH) in the paraventricular nucleus of the hypothalamus, which is considered as anorexigenic peptide. In contrast, a pair-fed group conformed by forced-food-restricted animals (FFR) (eating the exact same amount of food as dehydration-induced anorexic rats—DIA rats) present decreased TRH mRNA levels. NPY synthesis in the arcuate nucleus and orexin-expressing neurons from the lateral hypothalamic area (LHA) are activated during food restriction. These brain structures project into PVN, suggesting that NPY and orexins are possible factors involved in TRHergic neuron activation in DIA rats. Leptin signaling is another likely factor to be involved in TRH differential expression. Therefore, to gain more insight into the regulation of the feeding behavior in the experimental models, we analyzed Y1, Y5, Ox1-R and Ob-R_b mRNA levels in PVN and prepro-orexin in LHA, since their signaling to the PVN might be altering TRH synthesis and feeding in DIA animals. Prepro-orexinergic cells were activated in FFR animals; Ox1-R and Y1 expression was reduced in FFR vs. controls or DIA group. Compensatory changes in PVN receptor expression of some feeding-related peptides in anorexic rats may alter TRHergic neural response to energy demands.     

Tart cherry and pomegranate supplementations enhance recovery from exercise-induced muscle damage: a systematic review

Phenolic compounds have antioxidant and anti-inflammatory properties and may prevent inflammation and oxidative stress as well as help the athletes to recover from exercise-induced muscle damage (EIMD). Tart cherry (TC) and pomegranate (PG) are two fruits with high content of polyphenols. Their antioxidant and anti-inflammatory properties have recently attracted substantial interest for their potential to reduce strength loss and promote recovery from EIMD. The aims of this review are (1) to summarise the effects of tart cherry and pomegranate supplementation on oxidative stress, inflammation and recovery, and (2) to outline the differences found in supplementation with tart cherries or pomegranates. SPORTDiscus, PubMed, Web of Science and Scopus were searched according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis and 25 studies were included. The existing evidence suggests that both types of supplementation are good strategies to accelerate recovery of functional performance variables, perceptual variables and inflammation but PG supplementation shows better recovery of oxidative stress. However, positive effects are more likely: 1) when supplementation starts some days before muscle damage is induced and finishes some days after, for a total period of at least 8/10 days, 2) with pronounced muscle damage of the muscles involved, and 3) when total phenolic content is at least 1000 mg/day. This review may help to optimise TC or PG supplementation practice to improve post-exercise recovery.     

Application of NanoBiT for Monitoring Dimerization of the Null Hong Kong Variant of α-1-Antitrypsin,NHK, in Living Cells

In this study, we investigated expression and dimerization of an ER-associated degradation (ERAD) substrate, a null Hong Kong variant of α-1-antitrypsin (NHK) using immunoblotting assay and a novel NanoLuc complementary reporter system called the NanoBiT (NB) assay. This NB-tagged NHK made it possible to monitor the intra- and extracellular status of NHK in living cells. The values for this NB assay fluctuated in response to distinct pharmacological stimuli and co-transfection of several ERAD-related factors. We then focused on mesencephalic astrocyte-derived neurotrophic factor (MANF), an unclarified ATF6/IRE1-downstream target, and established MANF-deficient Neuro2a (N2a) cells using CRISPR/Cas9 system. MANF-deficient N2a significantly elevated OS-9 protein after tunicamycin treatment; however, no specific differences in intra- and extracellular status of NHK protein were observed between wild-type and MANF-deficient cells. Taken together, intrinsic MANF in N2a cells is not strongly associated with the accumulation and clearance of unfolded proteins within the ER under current condition, but this novel NB assay is a useful approach for characterizing the protein status including ERAD substrates.     

Impact of cyclic bending on coronary hemodynamics

Biomechanics and Modeling in Mechanobiology - It remains unknown that the degree of bias in computational fluid dynamics results without considering coronary cyclic bending. This study aims to...     

Measurement of DNA base and nucleotide excision repair activities in mammalian cells and tissues using the comet assay – A methodological overview

There is an increasing demand for phenotyping assays in the field of human functional genetics. DNA repair activity is representative of this functional approach, being seen as a valuable biomarker related to cancer risk. Repair activity is evaluated by incubating a cell extract with a DNA substrate containing lesions specific for the DNA repair pathway of interest. Enzymic incision at the lesion sites can be measured by means of the comet assay (single cell gel electrophoresis). The assay is particularly applicable for evaluation of base and nucleotide excision repair pathways (BER and NER). Substrate DNA containing oxidised purines gives a measure of BER, while UV-induced photolesions are the substrate for NER. While applications of comet-based DNA repair assays continue to increase, there are no commonly accepted standard protocols, which complicates inter-laboratory comparisons of results.     

Electrochemical characteristics of a hyperthermophilic enzyme in microdroplets stirred and heated by surface acoustic waves

Micro total analysis system (μTAS) is expected to be applied in various fields. In particular, since electrochemical measurement is inexpensive and easy, electrochemical measurement can be integrated with a microchannel. However, electrochemical detection sensitivity in a microchannel is lowered because the diffusion of the detection target is limited. In an ordinary electrochemical detection system, using a stirrer in a beaker can overcome limited diffusion. We previously proposed a new detection system that combines a microliquid solution agitation technology using surface acoustic waves (SAWs) with the μTAS. The SAWs function as microstirrers, thus making electrochemical detection possible by overcoming limited diffusion of the sample. However, when the solution is stirred by the SAWs, the temperature of the solution increases to 70°C due to vibrational energy. This leads to enzyme inactivation and impaired electrochemical response. Therefore, in this study, we used a hyperthermophile-derived enzyme. Temperature and electrochemical characteristics of the detection system using SAWs and a multi-copper oxidase (MCO) derived from the hyperthermophilic archaea Pyrobaculum aerophilum were studied. Laccase, which is an MCO derived from the thermophilic fungus Trametes versicolor, was also studied. We also characterized the enzyme-electrochemical reaction using SAWs by comparing the magnitude of the reduction current obtained using the two enzymes with different heat resistances. We observed an increase in the electrochemical response with the SAWs, without impaired enzyme activity. Thus, the use of a thermostable enzyme is suitable for the development of a biosensor that uses SAWs for agitation.