Amomum tsaoko fruit extract exerts anticonvulsant effects through suppression of oxidative stress and neuroinflammation in a pentylenetetrazol kindling model of epilepsy in mice

BackgroundChronic epilepsy is a multifaceted common brain disorder with manifold underlying factors. Epilepsy affects around 70 million peoples worldwide. Amomum tsaoko is a perennial herbaceous plant that is extensively cultivated in many provinces of China reported to exert immense biological activities.ObjectiveThis research work was aimed to reveal the therapeutic actions of ethanolic extract of A.tsaoko fruits (EE-ATF) against the pentylenetetrazol (PTZ)-provoked convulsive seizures in the mice.MethodologyThe convulsive seizures were provoked to the animals via administering 70 mg/kg of PTZ through intraperitoneally to trigger the convulsive seizures then treated with the EE-ATF at 50, 75, and 100 mg/kg orally 30 min prior to PTZ challenge. After the 30 min of PTZ challenge, animals closely monitored for signs of convulsion, generalized clonic and tonic convulsion durations, and mortality. A sub-convulsive dose 35 mg/kg of PTZ was used to provoke the kindling and seizure stages were examined using standard method. The levels of dopamine, GABA, glutamate, and Na + K + ATPase and Ca + ATPase activities in the brain tissues were studied using marker specific assay kits. The oxidative stress and antioxidant markers studied using standard methods. The mRNA expressions of COX-2, TNF-α, NF-κB, TLR-4, and IL-1β in the brain tissues were studied using RT-PCR analysis. The brain tissues were examined histologically.ResultsEE-ATF treatment remarkably decreased the onset and duration of convulsion and suppressed the seizure severity and mortality in the PTZ animals. EE-ATF treatment appreciably ameliorated the PTZ triggered modifications in the GABA, glutamate, dopamine levels and Ca + 2ATPase and Na + K + ATPase activities in the brain tissues. EE-ATF suppressed the mRNA expressions of NF-κB, IL-1β, TLR-4, TNF-α, and COX-2. The status of antioxidants were elevated by the EE-ATF. Histological findings also demonstrated the curative actions of EE-ATF.ConclusionOur findings evidenced that the EE-ATF substantially ameliorated the PTZ-provoked convulsive seizures in the mice.     

Investigating design principles of micropatterned encapsulation systems containing high-density microtissue arrays

Immunoisolation is an important strategy to protect transplanted cells from rejection by the host immune system.Recently,microfabrication techniques have been used to create hydrogel membranes to encapsulate microtissue in an arrayed organization.The method illustrates a new macroencapsulation paradigm that may allow transplantation of a large number of cells with microscale spatial control,while maintaining an encapsulation device that is easily maneuverable and remaining integrated following transplantation.This study aims to investigate the design principles that relate to the translational application of micropatterned encapsulation membranes,namely,the control over the transplantation density/quantity of arrayed microtissues and the fidelity of pre-formed microtissues to micropatterns.Agarose hydrogel membranes with microwell patterns were used as a model encapsulation system to exemplify these principles.Our results show that high-density micropatterns can be generated in hydrogel membranes,which can potentially maximize the percentage volume of cellular content and thereby the transplantation efficiency of the encapsulation device.Direct seeding of microtissues demonstrates that microwell structures can efficiently position and organize pre-formed microtissues,suggesting the capability of micropatterned devices for manipulation of cellular transplants at multicellular or tissue levels.Detailed theoretical analysis was performed to provide insights into the relationship between micropatterns and the transplantation capacity of membrane-based encapsulation.Our study lays the ground for developing new macroencapsulation systems with microscale cellular/tissue patterns for regenerative transplantation.     

Isolation and characterization of polysaccharides with the antitumor activity from Tuber fruiting bodies and fermentation system

Fifty-two polysaccharides were isolated from the fermentation systems of Tuber melanosporum, Tuber indicum, Tuber sinense, Tuber aestivum and the fruiting bodies of Tuber indicum, Tuber himalayense, Tuber sinense by elution with an activated carbon column. Polysaccharides from Tuber fermentation system exhibited relatively higher in vitro antitumor activity against HepG2, A549, HCT-116, SK-BR-3, and HL-60 cells than those from Tuber fruiting bodies. All polysaccharides were mainly composed of d-mannose, d-glucose, and d-galactose, which suggested that the polysaccharides from Tuber fruiting bodies and fermentation system have identical chemical compositions. The results of antitumor activity and structural identification indicated that the polysaccharide fractions could promote antitumor activity. Tuber polysaccharides from Tuber fermentation system exhibited relatively higher than that from Tuber fruiting bodies. These results confirm the potential of Tuber fermentation mycelia for use as an alternative resource for its fruiting bodies.     

Comparison of microbial communities in sequencing batch reactors (SBRs) exposed to trace erythromycin and erythromycin-H2O

Wastewater treatment plants (WWTPs) are major collection pools of antibiotics of which low concentrations may induce antibiotic resistance in their microbial communities and pose threat to human health. However, information is still limited on the microbial community alteration in WWTPs upon exposure to low-dose antibiotics due to absence of negative control systems without input of resistant bacteria and resistance genes. Here we report the impact of trace erythromycin (ERY) and dehydrated erythromycin (ERY-H₂O) on microbial community dynamics in three long-term (1 year) running sequencing batch reactors (SBRs), R1 (ERY-H₂O), R2 (ERY), and negative control R3. The PhyloChip microarray analysis showed that ERY-H₂O and ERY significantly altered their microbial communities based on bacterial richness (e.g., 825 operational taxonomic units (OTUs) in R1, 699 OTUs in R2, and 920 OTUs in R3) and population abundance (15 and 48 subfamilies with >80 % abundance decrease in R1 and R2, respectively). ERY-H₂O and ERY have broad but distinct antimicrobial spectrums. For example, bacteria of all the major phyla (i.e., Proteobacteria, Actinobacteria, Bacteroidetes, and Chloroflexi) present in SBRs were severely inhibited by ERY-H₂O and ERY, but bacteria of Acidobacteria, Chlorobi, Firmicutes, Nitrospira and OP10 phyla were only inhibited by ERY. Very limited bacterial groups showed antibiotic resistance to ERY-H₂O or ERY through forming biofilms (e.g., Zoogloea) or synthesizing resistant proteins (e.g., Thauera, Candidatus Accumulibacter, Candidatus Competibacter, and Dechloromonas) in the SBRs. Inhibition was observed to be the main effect of ERY-H₂O and ERY on microbial communities in the reactors. The results would broaden our knowledge of effects of low-dose antibiotics on microbial communities in WWTPs.     

Effects of Nickel Chloride on the Erythrocytes and Erythrocyte Immune Adherence Function in Broilers

This study was conducted to investigate the immune adherence function of erythrocytes and erythrocyte induced by dietary nickel chloride (NiCl₂) in broilers fed on a control diet and three experimental diets supplemented with 300, 600, and 900 mg/kg NiCl₂ for 42 days. Blood samples were collected from five broilers in each group at 14, 28, and 42 days of age. Changes of erythrocyte parameters showed that total erythrocyte count (TEC), hemoglobin (Hb) contents, and packed cell volume (PCV) were significantly lower (p?p?p?p?+/K⁺-ATPase) and calcium adenosine triphosphatase (Ca²⁺-ATPase) activities were significantly decreased (p?p?2-treated groups. The results of erythrocyte immune adherence function indicated that erythrocyte C_3b receptor rosette rate (E-C_3bRR) was significantly decreased (p?p?p?p?2 in excess of 300 mg/kg caused anemia and impaired the erythrocytic integrity, erythrocytic ability to transport oxygen, and erythrocyte immune adherence function in broilers. Impairment of the erythrocytes and erythrocyte immune adherence function was one of main effect mechanisms of NiCl₂ on the blood function.     

Overexpression of Camellia sinensis H1 histone gene confers abiotic stress tolerance in transgenic tobacco

Key message

Overexpression of CsHis in tobacco promoted chromatin condensation, but did not affect the phenotype. It also conferred tolerance to low-temperature, high-salinity, ABA, drought and oxidative stress in transgenic tobacco.

Abstract

H1 histone, as a major structural protein of higher-order chromatin, is associated with stress responses in plants. Here, we describe the functions of the Camellia sinensis H1 Histone gene (CsHis) to illustrate its roles in plant responses to stresses. Subcellular localization and prokaryotic expression assays showed that the CsHis protein is localized in the nucleus, and its molecular size is approximately 22.5 kD. The expression levels of CsHis in C. sinensis leaves under various conditions were investigated by qRT-PCR, and the results indicated that CsHis was strongly induced by various abiotic stresses such as low-temperature, high-salinity, ABA, drought and oxidative stress. Overexpression of CsHis in tobacco (Nicotiana tabacum) promoted chromatin condensation, while there were almost no changes in the growth and development of transgenic tobacco plants. Phylogenetic analysis showed that CsHis belongs to the H1C and H1D variants of H1 histones, which are stress-induced variants and not the key variants required for growth and development. Stress tolerance analysis indicated that the transgenic tobacco plants exhibited higher tolerance than the WT plants upon exposure to various abiotic stresses; the transgenic plants displayed reduced wilting and senescence and exhibited greater net photosynthetic rate (Pn), stomatal conductance (Gs) and maximal photochemical efficiency (Fv/Fm) values. All the above results suggest that CsHis is a stress-induced gene and that its overexpression improves the tolerance to various abiotic stresses in the transgenic tobacco plants, possibly through the maintenance of photosynthetic efficiency.     

Relationship between gene expression of UDP-glucose pyrophosphorylase and agar yield in Gracilariopsis lemaneiformis (Rhodophyta)

UDP-glucose pyrophosphorylase (UGPase) is an enzyme involved in the biosynthesis of UDP-D-galactose, a subunit of agar in red seaweeds. The relationship between agar content and expression levels of the UGPase encoding gene (glugp) was studied in thalli under different treatment conditions using a quantitative real-time PCR-based method (qPCR). Moreover, this qPCR method for the measurement of glugp expression was also applied to commercial varieties of Gracilariopsis lemaneiformis, a red macroalga, in order to examine its reliability on material obtained from field cultivation. Both the agar content and glugp gene expression in G. lemaneiformis grown under low salinity (17?‰) conditions for 1 week showed a slight increase in comparison with the control group (33?‰ salinity, natural salinity of seawater), but the difference was not statistically significant (P?>?0.05). However, when the culture time was extended to 2 weeks, the increase in both the agar yield and glugp expression became significant (P?glugp expression (P?>?0.05). Our results suggest that glugp gene expression and agar content are highly positively correlated and that the measurement of glugp expression, using only a small amount of thalli material, may be an efficient approach to evaluate agar content. In addition, both the agar content and glugp expression in cultivars 981, 07-2, and ZC differed significantly from those of MT-18. The findings of this study suggest that UGPase may be involved in agar biosynthesis and indicate that glugp gene expression could be a fairly reliable molecular marker to reflect the agar content of strains during breeding and selection of G. lemaneiformis.     

Whole-Genome Sequence Analysis and Genome-Wide Virulence Gene Identification of Riemerella anatipestifer Strain Yb2

Riemerella anatipestifer is a well-described pathogen of waterfowl and other avian species that can cause septicemic and exudative diseases. In this study, we sequenced the complete genome of R. anatipestifer strain Yb2 and analyzed it against the published genomic sequences of R. anatipestifer strains DSM15868, RA-GD, RA-CH-1, and RA-CH-2. The Yb2 genome contains one circular chromosome of 2,184,066 bp with a 35.73% GC content and no plasmid. The genome has 2,021 open reading frames that occupy 90.88% of the genome. A comparative genomic analysis revealed that genome organization is highly conserved among R. anatipestifer strains, except for four inversions of a sequence segment in Yb2. A phylogenetic analysis found that the closest neighbor of Yb2 is RA-GD. Furthermore, we constructed a library of 3,175 mutants by random transposon mutagenesis, and 100 mutants exhibiting more than 100-fold-attenuated virulence were obtained by animal screening experiments. Southern blot analysis and genetic characterization of the mutants led to the identification of 49 virulence genes. Of these, 25 encode cytoplasmic proteins, 6 encode cytoplasmic membrane proteins, 4 encode outer membrane proteins, and the subcellular localization of the remaining 14 gene products is unknown. The functional classification of orthologous-group clusters revealed that 16 genes are associated with metabolism, 6 are associated with cellular processing and signaling, and 4 are associated with information storage and processing. The functions of the other 23 genes are poorly characterized or unknown. This genome-wide study identified genes important to the virulence of R. anatipestifer.