Klebsiella pneumoniae increases invasion in intestinal epithelial cells by disrupting the cytoskeleton.

Klebsiella pneumoniae is an opportunistic pathogen and it can cause human mucosal lesions through the intestine, leading to bacteremia and abscess formation in liver and spleen. Previous studies have shown that K. pneumoniae can enter or cross cells through the intestinal epithelium, but the mechanism is unknown. In this study, we treated the intestinal epithelial cell line Caco-2 with KP1195, a clinically isolated strain with high adhesion and invasion of intestinal epithelial cells. The results showed that the treatment of K. pneumoniae could increase the expression of integrin gene and further disrupt the changes of cytoskeleton. Treating Caco-2 with cytoskeletal inhibitor cytorelaxin D can significantly increase the efficiency of K. pneumoniae invading Caco-2 cells. These data suggest that disruption of the cytoskeleton through integrins may be one of the mechanisms by which K. pneumoniae increases intracellular invasion. This study provides a theoretical basis for further understanding of the mechanism of K. pneumoniae entering intestinal epithelial cells.

Outer membrane vesicles induce the mussel plantigrade settlement via regulation of c-di-GMP.

Despite the importance of outer membrane vesicles (OMVs) in benthic animal settlement, the underlying molecular mechanism remains elusive. Here, the impact of OMVs and OMVs synthesis-related tolB gene in Mytilus coruscus plantigrade settlement was tested. The OMVs were extracted from Pseudoalteromonas marina through density gradient centrifugation, and a tolB knockout strain, achieved by homologous recombination, was utilized for the investigation. Our results demonstrated that OMVs could significantly enhance M. coruscus plantigrades settlement. Deleting the tolB resulted in downregulation of c-di-GMP, accompanied by a reduction of OMV production, a decline in bacterial motility and increasing biofilm-forming ability. Enzyme treatment resulted in a 61.11% reduction in OMV-inducing activity and a 94.87% reduction in LPS content. Thus, OMVs regulate mussel settlement via LPS, and c-di-GMP is responsible for the OMV-inducing capacity. These findings provide new insights into the interactions between bacteria and mussels.

Two-Component System Response Regulator ompR Regulates Mussel Settlement through Exopolysaccharides.

The outer membrane protein (OMP) is a kind of biofilm matrix component that widely exists in Gram-negative bacteria. However, the mechanism of OMP involved in the settlement of molluscs is still unclear. In this study, the mussel Mytilus coruscus was selected as a model to explore the function of ompR, a two-component system response regulator, on Pseudoalteromonas marina biofilm-forming capacity and the mussel settlement. The motility of the ΔompR strain was increased, the biofilm-forming capacity was decreased, and the inducing activity of the ΔompR biofilms in plantigrades decreased significantly (p < 0.05). The extracellular α-polysaccharide and ß-polysaccharide of the ΔompR strain decreased by 57.27% and 62.63%, respectively. The inactivation of the ompR gene decreased the ompW gene expression and had no impact on envZ expression or c-di-GMP levels. Adding recombinant OmpW protein caused the recovery of biofilm-inducing activities, accompanied by the upregulation of exopolysaccharides. The findings deepen the understanding of the regulatory mechanism of bacterial two-component systems and the settlement of benthic animals.

Analysis of Medication Rules of Traditional Chinese Medicine for Malaria Treatment Based on Data Mining.

Objective To analyze the medication rules of traditional Chinese medicine (TCM) for malaria treatment.Methods Statistical analysis was conducted on the basic attributes of TCM drugs with regard to property, therapeutic methods, flavor, and meridian tropism. A complex network of TCM drug associations was constructed. Cluster analysis was applied to obtain the core drugs for malaria treatment. The Apriori algorithm was applied to analyze the association rules of these core drugs.Results A total of 357 herbs were used 3,194 times in 461 prescriptions for malaria treatment. Radix Glycyrrhizae (), Rhizoma Pinelliae (), Radix Bupleuri (), and Radix Dichroae () were the frequently used herbs through supplementing, exterior-releasing, heat-clearing, qi-rectifying, and damp-resolving therapeutic methods. Such herbs had warm, natural, and cold herbal properties; pungent, bitter, and sweet flavors; and spleen, lung, and stomach meridian tropisms. Cluster analysis showed 61 core drugs, including Radix Glycyrrhizae, Rhizoma Pinelliae, Radix Bupleuri, and Radix Scutellariae (). Apriori association rule analysis yielded 12 binomial rules (herb pairs) and 6 trinomial rules (herb combinations). Radix Bupleuri plus Radix Scutellariae was the core herbal pair for treating malaria. This pair could be combined with Rhizoma Atractylodis Macrocephalae () for treating warm or cold malaria, combined with Pericarpium Citri Reticulatae () or Radix Dichroae () for treating miasmic malaria, or combined with turtle shells () for treating malaria with splenomegaly.Conclusions TCM can be used to classify and treat malaria in accordance with the different stages of development. As the core herbal pair, Radix Bupleuri and Radix Scutellariae can be combined with other drugs to treat malaria with different syndrome types.

Theoretical study on ferroelectric nitrides with super-wurtzite structures for solar energy conversion applications.

Polarized structured nitride semiconductors are attractive due to their unique and environment-friendly electronic properties. The stability, ferroelectricity and photocatalytic and photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc and W) were determined based on first principles calculations in this study. The calculated results indicate that Mg2XN3 (X = Sb, Ta, Bi and Nb) are stable polar nitrides by phonon frequencies, elastic coefficients and ferroelectric analysis. Mg2XN3 (X = Sb, Ta and Nb) with large ferroelectric polarization strength could absorb ultraviolet light to promote photocatalytic water splitting for hydrogen production. Mg2BiN3 is a new excellent photovoltaic candidate due to its ideal energy band, high electron mobility, high absorption coefficient and large ferroelectric polarization strength.

Visualizing coherent intermolecular dipole-dipole coupling in real space.

Many important energy-transfer and optical processes, in both biological and artificial systems, depend crucially on excitonic coupling that spans several chromophores. Such coupling can in principle be described in a straightforward manner by considering the coherent intermolecular dipole-dipole interactions involved. However, in practice, it is challenging to directly observe in real space the coherent dipole coupling and the related exciton delocalizations, owing to the diffraction limit in conventional optics. Here we demonstrate that the highly localized excitations that are produced by electrons tunnelling from the tip of a scanning tunnelling microscope, in conjunction with imaging of the resultant luminescence, can be used to map the spatial distribution of the excitonic coupling in well-defined arrangements of a few zinc-phthalocyanine molecules. The luminescence patterns obtained for excitons in a dimer, which are recorded for different energy states and found to resemble σ and π molecular orbitals, reveal the local optical response of the system and the dependence of the local optical response on the relative orientation and phase of the transition dipoles of the individual molecules in the dimer. We generate an in-line arrangement up to four zinc-phthalocyanine molecules, with a larger total transition dipole, and show that this results in enhanced 'single-molecule' superradiance from the oligomer upon site-selective excitation. These findings demonstrate that our experimental approach provides detailed spatial information about coherent dipole-dipole coupling in molecular systems, which should enable a greater understanding and rational engineering of light-harvesting structures and quantum light sources.

Reduction of mussel metamorphosis by inactivation of the bacterial thioesterase gene via alteration of the fatty acid composition.

The molecular mechanism underlying modulation of metamorphosis of the bivalve Mytilus coruscus by bacteria remains unclear. Here, the functional role of the thioesterase gene tesA of the bacterium Pseudoalteromonas marina in larval metamorphosis was examined. The aim was to determine whether inactivation of the tesA gene altered the biofilm-inducing capacity, bacterial cell motility, biopolymers, or the intracellular c-di-GMP levels. Complete inactivation of tesA increased the c-di-GMP content in P. marina, accompanied by a reduced fatty acid content, weaker motility, upregulation of bacterial aggregation, and biofilm formation. The metamorphosis rate of mussel larvae on ΔtesA biofilms was reduced by ∼ 80% compared with those settling on wild-type P. marina. Exogenous addition of a mixture of extracted fatty acids from P. marina into the ΔtesA biofilms promoted the biofilm-inducing capacity. This study suggests that the bacterial thioesterase gene tesA altered the fatty acid composition of ΔtesA P. marina biofilms (BF) through regulation of its c-di-GMP, subsequently impacting mussel metamorphosis.

Thyroid hormone receptor: A new player in epinephrine-induced larval metamorphosis of the hard-shelled mussel.

Many marine invertebrate larvae undergo a dramatic morphological and physiological transition from a planktonic larva to a benthic juvenile. The mechanisms of this metamorphosis in bivalves are mainly unknown. The recent identification in bivalves of a thyroid hormone receptor (TR) gene raises the possibility that as occurs in vertebrate metamorphosis, TRs regulate this developmental process. An evolutionary study of TR receptors revealed they are ubiquitous in the molluscs. Knock-down of the TR gene in pediveliger larvae of the hard-shelled mussel, Mytilus coruscus (Mc), using electroporation of siRNA significantly (p < 0.01) reduced TR gene expression. TR gene knock-down decreased pediveliger larval metamorphosis by 54% and was associated with a significant (p < 0.01) reduction in viability compared to control larvae. The TR in the hard-shelled mussel appears to be an essential regulatory factor for the successful epinephrine-induced metamorphosis of the pediveliger larvae to post-larvae. It is hypothesised that the knock-down of TR by siRNA transfection affects the "competence" of pediveliger larvae for the metamorphic transition by reducing their ability to respond to the inducer. The involvement of TR in the epinephrine-induced metamorphosis of a mollusc, the hard-shelled mussel, suggests the role of TR in this process probably emerged early during evolution.

A bacterial polysaccharide biosynthesis-related gene inversely regulates larval settlement and metamorphosis of Mytilus coruscus.

Larval settlement and metamorphosis is essential for the development of marine invertebrates. Although polysaccharides are involved in larval settlement and metamorphosis of Mytilus coruscus, the molecular basis of polysaccharides underlying this progression remains largely unknown. Here, the roles of the polysaccharide biosynthesis-related gene 01912 of Pseudoalteromonas marina ECSMB14103 in the regulation of larval settlement and metamorphosis were examined by gene-knockout technique. Compared with biofilms (BFs) of the wild-type P. marina, Δ01912 BFs with a higher colanic acid (CA) content showed a higher inducing activity on larval settlement and metamorphosis. Deletion of the 01912 gene caused an increase in c-di-GMP levels, accompanied by a decrease in the motility, an increase in cell aggregation, and overproduction of CA. Thus, the bacterial polysaccharide biosynthesis-related gene 01912 may regulate mussel settlement by producing CA via the coordination of c-di-GMP. This work provides a deeper insight into the molecular mechanism of polysaccharides in modulating mussel settlement.

The Flagellar Gene Regulates Biofilm Formation and Mussel Larval Settlement and Metamorphosis.

Biofilms are critical components of most marine systems and provide biochemical cues that can significantly impact overall community composition. Although progress has been made in the bacteria-animal interaction, the molecular basis of modulation of settlement and metamorphosis in most marine animals by bacteria is poorly understood. Here, Pseudoalteromonas marina showing inducing activity on mussel settlement and metamorphosis was chosen as a model to clarify the mechanism that regulates the bacteria-mussel interaction. We constructed a flagellin synthetic protein gene fliP deletion mutant of P. marina and checked whether deficiency of fliP gene will impact inducing activity, motility, and extracellular polymeric substances of biofilms. Furthermore, we examined the effect of flagellar proteins extracted from bacteria on larval settlement and metamorphosis. The deletion of the fliP gene caused the loss of the flagella structure and motility of the ∆fliP strain. Deficiency of the fliP gene promoted the biofilm formation and changed biofilm matrix by reducing ß-polysaccharides and increasing extracellular proteins and finally reduced biofilm-inducing activities. Flagellar protein extract promoted mussel metamorphosis, and ∆fliP biofilms combined with additional flagellar proteins induced similar settlement and metamorphosis rate compared to that of the wild-type strain. These findings provide novel insight on the molecular interactions between bacteria and mussels.

Two toll-like receptors identified in the mantle of Mytilus coruscus are abundant in haemocytes.

Toll-like receptors (TLRs) are a large family of pattern recognition receptors (PRRs) that play a critical role in innate immunity. TLRs are activated when they recognize microbial associated molecular patterns (MAMPs) of bacteria, viruses, or fungus. In the present study, two TLRs were isolated from the mantle of the hard-shelled mussel (Mytilus coruscus) and designated McTLR2 and McTLR3 based on their sequence similarity and phylogenetic clustering with Crassostrea gigas, CgiTLR2 and CgiTLR3, respectively. Quantitative RT-PCR analysis demonstrated that McTLR2 and McTLR3 were constitutively expressed in many tissues but at low abundance.

Polymorphism analyses of 19 STRs in Labrador Retriever population from China and its heterozygosity comparisons with other retriever breeds.

Pure breed dogs of Western origin are increasingly more popular in China as is a need to differentiate breeds and individual dogs for personal and forensic reasons. Research on genetic diversities of the canine population in China is rarely conducted. In this study, genetic distributions and forensic efficiencies of 19 canine STR loci in Labrador Retriever population from China were evaluated by using one available commercial canine kit in China. This panel was used to genetically define 214 Labrador Retrievers in China, as an example of one of the most important Western breeds and to compare them with Labrador Retrievers from America based on three overlapping STR loci. Moreover, genetic relationship analyses between Labrador Retriever population and two reference populations in America were performed. All 19 STR loci were polymorphic and conformed to Hardy-Weinberg equilibrium in the studied population. The STR panel was able to discern individual dogs with a high degree of accuracy. Breed-wide genetic heterozygosity comparisons based on present and published allele frequencies revealed that the studied population had the lower genetic heterozygosity than canine populations in America. Principal component analysis among Labrador Retriever population and other reference populations showed that the studied Labrador Retrievers were genetically close to the retriever breeds in America. Population genetic structure analyses among these canine breeds further revealed genetic differentiations between the studied Labrador Retriever population and other compared breeds. In conclusion, these STR loci had relatively high forensic values in Labrador Retriever population in China, which could be employed for individual identification and kinship testing.

An ɑ2-adrenergic receptor is involved in larval metamorphosis in the mussel, Mytilus coruscus.

Metamorphosis is crucial in the life-cycle transition between the larval and juvenile stages of marine invertebrates. Although a number of agonists and antagonists of the adrenergic receptor (AR) are known to regulate larval metamorphosis in Mytilus coruscus (Mc), the molecular basis of the modulation of larval metamorphosis by the AR gene in this species remains elusive. Herein, the role of the AR gene in M. coruscus larval metamorphosis using the RNA interference technique was examined. The Mcα2AR transcript was observed to be present during the entire process of larval development and its level in the post-larvae was significantly increased compared to that in the pediveligers. Mcα2AR-knockdown resulted in a substantial reduction in the abundance of the Mcα2AR transcript and significantly inhibited the metamorphosis of M. coruscus larvae. These findings provide new insights into the molecular basis of modulation of larval metamorphosis in M. coruscus by the AR gene.

Transcriptome-Wide Identification and Prediction of miRNAs and Their Targets in Paris polyphylla var. yunnanensis by High-Throughput Sequencing Analysis.

Long dormancy period of seeds limits the large-scale artificial cultivation of the scarce Paris polyphylla var. yunnanensis, an important traditional Chinese medicine. Characterizing miRNAs and their targets is crucial to understanding the role of miRNAs during seed dormancy in this species. Considering the limited genome information of this species, we first sequenced and assembled the transcriptome data of dormant seeds and their seed coats as the reference genome. A total of 146,671 unigenes with an average length of 923 bp were identified and showed functional diversity based on different annotation methods. Two small RNA libraries from respective seeds and seed coats were sequenced and the combining data indicates that 263 conserved miRNAs belonging to at least 83 families and 768 novel miRNAs in 1174 transcripts were found. The annotations of the predicted putative targets of miRNAs suggest that these miRNAs were mainly involved in the cell, metabolism and genetic information processing by direct and indirect regulation patterns in dormant seeds of P. polyphylla var. yunnanensis. Therefore, we provide the first known miRNA profiles and their targets, which will assist with further study of the molecular mechanism of seed dormancy in P. polyphylla var. yunnanensis.

The effect of carbon nanotubes and titanium dioxide incorporated in PDMS on biofilm community composition and subsequent mussel plantigrade settlement.

This study investigated the effect of carbon nanotubes (CNTs) and titanium dioxide (TiO2) incorporated in PDMS on biofilm formation and plantigrade settlement of Mytilus coruscus. TiO2 increased bacterial density, and CNTs also increased bacterial density but reduced diatom density in biofilms after 28 days. Further analysis was conducted between bacterial communities on glass, PDMS, CNTs (0.5 wt%) and TiO2 (7.5 wt%). ANOSIM analysis revealed significant differences (R > 0.9) between seven, 14, 21 and 28 day-old bacterial communities. MiSeq sequencing showed that CNTs and TiO2 impacted the composition of 28 day-old bacterial communities by increasing the abundance of Proteobacteria and decreasing the abundance of Bacteroidetes. The maximum decreased settlement rate in 28 day-old biofilms on CNTs and TiO2 was > 50% in comparison to those on glass and PDMS. Thus, CNTs and TiO2 incorporated in PDMS altered the biomass and community composition of biofilms, and subsequently decreased mussel settlement.

Cadmium Activates Reactive Oxygen Species-dependent AKT/mTOR and Mitochondrial Apoptotic Pathways in Neuronal Cells.

OBJECTIVE: To examine the role of Cd-induced reactive oxygen species (ROS) generation in the apoptosis of neuronal cells. METHODS: Neuronal cells (primary rat cerebral cortical neurons and PC12 cells) were incubated with or without Cd post-pretreatment with rapamycin (Rap) or N-acetyl-L-cysteine (NAC). Cell viability was determined by MTT assay, apoptosis was examined using flow cytometry and fluorescence microscopy, and the activation of phosphoinositide 3'-kinase/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) and mitochondrial apoptotic pathways were measured by western blotting or immunofluorescence assays. RESULTS: Cd-induced activation of Akt/mTOR signaling, including Akt, mTOR, p70 S6 kinase (p70 S6K), and eukaryotic initiation factor 4E binding protein 1 (4E-BP1). Rap, an mTOR inhibitor and NAC, a ROS scavenger, blocked Cd-induced activation of Akt/mTOR signaling and apoptosis of neuronal cells. Furthermore, NAC blocked the decrease of B-cell lymphoma 2/Bcl-2 associated X protein (Bcl-2/Bax) ratio, release of cytochrome c, cleavage of caspase-3 and poly(ADP-ribose) polymerase (PARP), and nuclear translocation of apoptosis-inducing factor (AIF) and endonuclease G (Endo G). CONCLUSION: Cd-induced ROS generation activates Akt/mTOR and mitochondrial pathways, leading to apoptosis of neuronal cells. Our findings suggest that mTOR inhibitors or antioxidants have potential for preventing Cd-induced neurodegenerative diseases.

[Preventive Effect of Different Compatibilities of Ramulus Cinnamomi and Radix Paeomlae alba in Guizhi Decoction on Cardiac Sympathetic Denervation Induced by 6-OHDA].

OBJECTIVE: To observe the preventive effect of different compatibilities of Ramulus Cinnamomi (RC) and Radix Paeomiae alba (RPA) in Guizhi Decoction (GZD) on neurotransmitters and their rate-limiting enzymes, and neurotrophic factors of cardiac sympathetic denervation model rats induced by 6-hydroxydopamine (6-OHDA). METHODS: Totally 54 male Wistar rats were randomly divided into 6 groups, i.e., the blank control group, the model group, the methycobal group, the 2:1 (RC/RPA) Guishao group, the 1:2 Guishao group, and the 1:1 Guishao group, 9 in each group. Sympathetic denervation was induced by intraperitoneal injection of 6-OHDA for three successive days. Rats in the methycobal group and GZD groups were administered with corresponding decoction by gastrogavage 1 week before modeling (methycobal at the daily dose 0.15 mg/kg; GZD at the daily dose of 4.0, 5.5, 5.5 g crude drugs/kg for GZD 1:1, 1:2, and 2:1 groups). All medication lasted for 10 successive days. Levels of norepinephrine (NE), tyrosine hydroxylase (TH), choline acetyl-transferase (ChAT), nerve growth factor (NGF), growth associated protein43 (GAP-43) and ciliary neurotrophic factor (CNTF) in myocar- dial homogenates of right atrium and ventricular septum were detected by ELISA. RESULTS: Compared with the blank control group, levels of NE, TH, TH/ChAT ratio, and GAP-43 in myocardial homogenates of right atrium and ventricular septum decreased in the model group, and level of NGF increased (P < 0.01, P < 0.05). Compared with the model group, levels of NE and GAP-43 increased in the right atrium and interventricular septum; NGF level of the ventricular septum decreased in the methycobal group and each GZD groups. TH and TH/ChAT ratio in the right atrium increased in the 2:1 Guishao group and the 1:2 Guishao group (P < 0.01, P < 0.05); NGF levels in the right atrium and interventricular septum decreased only in the 1:1 Guishao group (P < 0.01, P< 0.05). Compared with the methycobal group, levels of NE, TH, and GAP-43 in the right atrium and interventricular septum increased, and NGF levels in the right atrium and interventricular septum decreased in the 1:1 Guishao group (P < 0.05). Compared with the methycobal group, levels of NE and GAP-43 in interventricular septum increased in the 2:1 Guishao group (P < 0.05). CONCLUSION: GZD (with the proportion between RC and RPA 2:1 and 1:1) could improve contents of neurotransmitters and their rate-limiting enzymes, as well as neurotrophic factors in cardiac sympathetic denervation model rats induced by 6-OHDA, alleviate cardiac sympathetic denervation induced by 6-OHDA, and maintain the balance of sympathetic-vagal nerve system.

Characterization of self-generated variants in Pseudoalteromonas lipolytica biofilm with increased antifouling activities.

Pseudoalteromonas is widespread in various marine environments, and most strains can affect invertebrate larval settlement and metamorphosis by forming biofilms. However, the impact and the molecular basis of population diversification occurring in Pseudoalteromonas biofilms are poorly understood. Here, we show that morphological diversification is prevalent in Pseudoalteromonas species during biofilm formation. Two types of genetic variants, wrinkled (frequency of 12±5%) and translucent (frequency of 5±3%), were found in Pseudoalteromonas lipolytica biofilms. The inducing activities of biofilms formed by the two variants on larval settlement and metamorphosis of the mussel Mytilus coruscus were significantly decreased, suggesting strong antifouling activities. Using whole-genome re-sequencing combined with genetic manipulation, two genes were identified to be responsible for the morphology alternations. A nonsense mutation in AT00_08765 led to a wrinkled morphology due to the overproduction of cellulose, whereas a point mutation in AT00_17125 led to a translucent morphology via a reduction in capsular polysaccharide production. Taken together, the results suggest that the microbial behavior on larval settlement and metamorphosis in marine environment could be affected by the self-generated variants generated during the formation of marine biofilms, thereby rendering potential application in biocontrol of marine biofouling.

[Effects of Different Compatibilities of Ramulus Cinnamomi and Peony in Guizhi Decoction on Diabetic Cardiac Autonomic Neuropathy].

OBJECTIVE: To observe the preventive effect different compatibilities of Ramulus Cinnamomi (RC) and peony in Guizhi Decoction (GD) on diabetic cardiac autonomic neuropathy (DCAN). METHODS: Totally 60 male rats were randomly divided into 5 groups, i.e., the blank control DM group, the model group, the methycobal group, the 1:1 (RC/peony) Guishao group, the 2:1 Guishao group, and the 1:2 Guishao group, 10 in each group. Rats were pretreated with corresponding drugs for 1 week, and then induced diabetes by intraperitoneal injection of STZ. Drugs were administrated by gastrogavage for 4 more weeks after STZ-injection. Enzyme-linked immunosorbent assay (ELISA) was employed to detect levels of tyrosine hydroxylase (TH), choline acetyltransferase (CHAT), nerve growth factor. (NGF), and ciliary neurotrophic factor (CNTF) in myocardial homogenates. RESULTS: After 4-week modeling, body weight (BW) was obviously lower, but blood glucose (BG) was higher in STZ rats than in rats of the blank control DM group. There was no statistical difference in BW or BG among the 5 groups (P >0.05). Compared with the blank control group, TH, TH/CHAT, and NGF in left ventricle and ventricular septum increased, CHAT and CNTF increased in the model group (P < 0.05, P < 0.01). Compared with the model group, TH and TH/CHAT in left ventricle decreased (P < 0.05, P < 0.01), CNTF in left ventricle increased (P < 0.05), CHAT in left ventricle and ventricular septum increased (P < 0.05, P < 0.01) in the methycobal group. TH and TH/CHAT in left ventricle and ventricular septum decreased, CNTF in left ventricle and ventricular septum increased (P < 0.05, P < 0.01), CHAT in left ventricle and ventricular septum increased (P < 0.01), NGF in ventricular septum decreased (P < 0.01) in the 1:1 Guishao group. TH/CHAT in left ventricle decreased (P < 0.01), CHAT and CNTF in left ventricle and ventricular septum increased (P < 0.05, P < 0.01) in the 1:2 Guishao group. Compared with the methycobal group, CHAT in left ventricle decreased, TH and TH/CHAT in left ventricle increased in the 2:1 Guishao group (P < 0.05, P < 0.01). TH and TH/CHAT in ventricular septum decreased (P < 0.05), CHAT and CNTF in left ventricle and ventricular septum increased (P < 0.05, P < 0.01) in the 1:1 Guishao group. Compared with the 1:2 Guishao group and the 2:1 Guishao group, CHAT in left ventricle increased, TH/CHAT in left ventricle decreased, TH and TH/CHAT in ventricular septum decreased, CHAT in ventricular septum increased, CNTF in left ventricle and ventricular septum also increased in the 1:1 Guishao group (all P < 0.01). CONCLUSIONS: STZ model rats had autonomic neural injury, manifested as lowered vagal nerve activity and hyperactive sympathetic nerves. GD could effectively suppress hyperactive cardiac sympathetic nerves and protect the vagus. Besides, GD (1:1) showed the optimal effect in regulating the balance of cardiac autonomic nerves and could be used in early prevention of DCAN.

Bacterial c-di-GMP triggers metamorphosis of mussel larvae through a STING receptor.

Bacteria induced metamorphosis observed in nearly all marine invertebrates. However, the mechanism of bacteria regulating the larvae-juvenile metamorphosis remains unknown. Here, we test the hypothesis that c-di-GMP, a ubiquitous bacterial second-messenger molecule, directly triggers the mollusc Mytilus coruscus larval metamorphosis via the stimulator of interferon genes (STING) receptor. We determined that the deletion of c-di-GMP synthesis genes resulted in reduced c-di-GMP levels and biofilm-inducing activity on larval metamorphosis, accompanied by alterations in extracellular polymeric substances. Additionally, c-di-GMP extracted from tested varying marine bacteria all exhibited inducing activity on larval metamorphosis. Simultaneously, through pharmacological and molecular experiments, we demonstrated that M. coruscus STING (McSTING) participates in larval metamorphosis by binding with c-di-GMP. Our findings reveal that new role of bacterial c-di-GMP that triggers mussel larval metamorphosis transition, and extend knowledge in the interaction of bacteria and host development in marine ecosystems.