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Biotrophic pathogens are believed to strategically manipulate sugar transport in host cells to enhance their access to carbohydrates. However, mechanisms of sugar translocation from host cells to biotrophic fungi such as powdery mildew across the plant-haustorium interface remain poorly understood. To investigate this question, systematic subcellular localisation analysis was performed for all the 14 members of the monosaccharide sugar transporter protein (STP) family in Arabidopsis thaliana. The best candidate AtSTP8 was further characterised for its transport properties in Saccharomyces cerevisiae and potential role in powdery mildew infection by gene ablation and overexpression in Arabidopsis. Our results showed that AtSTP8 was mainly localised to the endoplasmic reticulum (ER) and appeared to be recruited to the host-derived extrahaustorial membrane (EHM) induced by powdery mildew. Functional complementation assays in S. cerevisiae suggested that AtSTP8 can transport a broad spectrum of hexose substrates. Moreover, transgenic Arabidopsis plants overexpressing AtSTP8 showed increased hexose concentration in leaf tissues and enhanced susceptibility to powdery mildew. Our data suggested that the ER-localised sugar transporter AtSTP8 may be recruited to the EHM where it may be involved in sugar acquisition by haustoria of powdery mildew from host cells in Arabidopsis.

Eriocitrin, a lemons flavanone, exhibits several biological properties, antiproliferative, and proapoptotic effects. However, its molecular mechanical action is not entirely clarified. Oxidative stress causes abnormal stimulation of signal transducer and activator of transcription 3 (STAT3) and c-Jun NH2-terminal kinase (JNK), p38 mitogen-activated protein kinases (MAPKs) signaling has been strongly connected with the ruling of cell survival and apoptosis of cancer cells. Herein, we investigated an antiproliferative and proapoptotic effect that Eriocitrin modulates STAT3/MAPKs signaling activation in MCF-7 cells. We noticed that Eriocitrin strongly enhances reactive oxygen species (ROS) generation, alteration of mitochondrial outer membrane potential, and enhances apoptotic morphological changes. Furthermore, Eriocitrin suppressed STAT3 phosphorylation via inhibiting an upstream molecule of JAK2 and Src kinase activation, thereby blocking STAT3 nuclear translocation. Similarly, Eriocitrin causes oxidative stress-mediated JNK/p38 MAPK signaling activation. We confirmed that Eriocitrin induced ROS-mediated apoptosis inhibited by the antioxidant substance of N-acetylcysteine. Eriocitrin induced apoptosis via suppression of STAT3 signaling regulated proteins, activating proapoptotic factors Bax, caspase 7, 8, 9 and suppressing Bcl-2, Bcl-x expression in MCF-7 cells. Overall, these results evidenced that Eriocitrin can affect multiple signaling events associated with tumorigenesis. From this evidence, Eriocitrin, a novel chemotherapeutic agent, can be used to treat breast cancer.

Background Atractylodes lancea (Thunb.) DC, a medicinal herb belonging to the Asteraceae family, often faces severe drought stress during its growth. Until now, there has been no research on the effect of drought stress on the quality formation of A. lancea. Therefore, the present study aimed to study the effects of drought stress on A. lancea through physical and chemical analysis, and to reveal the related molecular mechanisms via transcriptome analysis. Results The photosynthesis was markedly inhibited under drought stress. There were alterations to photosynthetic parameters (Pn, Gs, Ci) and chlorophyll fluorescence (Fv/Fm, NPQ), and the chlorophyll content decreased. Twenty genes encoding important regulatory enzymes in light and dark reactions, including the Rubisco gene of the Calvin cycle, were significantly downregulated. After exposure to drought stress for more than 4 days, the activities of four antioxidative enzymes (SOD, POD CAT and APX) began to decrease and continued to decrease with longer stress exposure. Meanwhile, most of the genes encoding antioxidative enzymes were downregulated significantly. The downregulation of 21 genes related to the respiratory electron transport chain indicated that the blocked electron transfer accelerated excessive ROS. The MDA content was significantly elevated. The above data showed that 15 days of drought stress caused serious oxidative damage to A. lancea. Drought stress not only reduced the size and dry weight of A. lancea, but also lowered the amount of total volatile oil and the content of the main bioactive components. The total volatile oil and atractylodin content decreased slightly, whereas the content of atractylon and β-eudesmol decreased significantly. Moreover, ten significantly downregulated genes encoding sesquiterpene synthase were mainly expressed in rhizomes. Conclusions After exposed to drought stress, the process of assimilation was affected by the destruction of photosynthesis; stress tolerance was impaired because of the inhibition of the antioxidative enzyme system; and bioactive component biosynthesis was hindered by the downregulation of sesquiterpene synthase-related gene expression. All these had negative impacts on the quality formation of A. lancea under drought stress.

Vascular complications of diabetes are a serious challenge in clinical practice, and effective treatments are an unmet clinical need. Acidic fibroblast growth factor (aFGF) has potent anti-oxidative properties and therefore has become a research focus for the treatment of diabetic vascular complications. However, the specific mechanisms by which aFGF regulates these processes remain unclear. The purpose of this study was to investigate whether aFGF alleviates diabetic endothelial dysfunction by suppressing mitochondrial oxidative stress. We found that aFGF markedly decreased mitochondrial superoxide generation in both db/db mice and endothelial cells incubated with high glucose (30 mM) plus palmitic acid (PA, 0.1 mM), and restored diabetes-impaired Wnt/β-catenin signaling. Pretreatment with the Wnt/β-catenin signaling inhibitors IWR-1-endo (IWR) and ICG-001 abolished aFGF-mediated attenuation of mitochondrial superoxide generation and endothelial protection. Furthermore, the effects of aFGF on endothelial protection under diabetic conditions were suppressed by c-Myc knockdown. Mechanistically, c-Myc knockdown triggered mitochondrial superoxide generation, which was related to decreased expression and subsequent impaired mitochondrial localization of hexokinase 2 (HXK2). The role of HXK2 in aFGF-mediated attenuation of mitochondrial superoxide levels and EC protection was further confirmed by si-Hxk2 and a cell-permeable form of hexokinase II VDAC binding domain (HXK2VBD) peptide, which inhibits mitochondrial localization of HXK2. Taken together, these findings suggest that the endothelial protective effect of aFGF under diabetic conditions could be partly attributed to its role in suppressing mitochondrial superoxide generation via HXK2, which is mediated by the Wnt/β-catenin/c-Myc axis.

The traditional anoxic/aerobic process (A/O) process is widely used for treating digested piggery wastewater, but the lack of carbon sources leads to poor efficiency. Therefore, the process needs optimization to achieve high-efficiency and low-cost operation mode. In this study, an improved A/O system with bionic aquatic weed and Myriophyllum sp. was established to decontaminate digested piggery wastewater. The average removal efficiencies of chemical oxygen demand (COD), NH4+-N, and total nitrogen (TN) by the improved A/O system was satisfactory. The average removal efficiencies of COD, NH4+-N, and TN were 62.1%, 87.5%, and 61.9%, respectively. High-throughput sequencing identified a number of dominant microorganisms. The relative abundance of Nitrosomonas (ammonia-oxidizing bacteria) and Nitrospira (nitrite-oxidizing bacteria) was 0.07%-3.52% and 0.32%-1.30%, respectively. Combining bionic aquatic weed and Myriophyllum sp. altered the microbial community structure and metabolic pathways. The results demonstrate a cost-effective method for treating digested piggery wastewater.

Secretory carrier membrane proteins (SCAMPs) play an important role in exocytosis in animals, but the precise function of SCAMPs in human disease is unknown. In this study, we identified a homozygous mutation, SCAMP5 R91W, in a Chinese consanguineous family with pediatric epilepsy and juvenile Parkinson's disease. Scamp5 R91W mutant knock-in mice showed typical early-onset epilepsy similar to that in humans. Single-neuron electrophysiological recordings showed that the R91W mutation significantly increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) at a resting state and also increased the amplitude of evoked EPSCs. The R91W mutation affected the interaction between SCAMP5 and synaptotagmin 1 and may affect the function of the SNARE complex, the machinery required for vesicular trafficking and neurotransmitter release. Our work shows that dysfunction of SCAMP5 shifted the excitation/inhibition balance of the neuronal network in the brain, and the deficiency of SCAMP5 leads to pediatric epilepsy.

Alzheimer's disease (AD) is a chronic central neurodegenerative disease. The pathological features of AD are the extracellular deposition of senile plaques formed by amyloid-β oligomers (AβOs) and the intracellular accumulation of neurofibrillary tangles. However, due to the lack of effective method and experimental models to study the cognitive decline, communication at cell resolution and the implementation of interventions, the diagnosis and treatment on AD still progress slowly. In this paper, we established a pathological model of AD in vitro based on AβOs-induced hippocampal neuronal network chip for multi-site dynamic analysis of the neuronal electrical activity and network connection. The multiple characteristic parameters, including positive and negative spike intervals, firing rate and peak-to-peak values, were extracted through the analysis of spike signals, and two firing patterns from the interneurons and pyramidal neurons were recorded. The spatial firing patterns mapping and cross-correlation between channels were performed to validate the degeneration of neuronal network connectivity. Moreover, an electrical stimulation with frequency at 40 Hz was exerted to preliminarily explore the therapeutic effect on the pathological model of AD. This neuronal network chip enables the implementation of AD models in vitro for studying basic mechanisms of neurodegeneration within networks and for the parallel testing of various potential therapies. It can be a novel technique in the research of AD pathological model in vitro.

Alzheimer disease (AD) is a chronic neurodegenerative disease threating the health of human being. The clinical symptoms mainly consist of severe cognitive impairment, comprehensive dementia, memory loss and other mental behavioral problems. According to data that collected in 2018, AD has become the sixth fatal disease in the worldwide. Nevertheless, the pathogenesis of AD has not been clarified, except for two main pathological features: from extracellular, the amyloid plagues appear in the dendrites which is mainly caused by the formation of the toxic amyloid-β oligomers (AβOs); from intracellular, it appears the accumulation of neurofibrillary tangles (NFTs) which is formed by hyperphosphorylated tau protein. Recent years, olfactory dysfunction has been reported to be an early symptom of AD. From the research of clinical experiment, olfactory dysfunction happens much earlier than other clinical symptoms. Besides, there have been plentiful methods for olfactory dysfunction diagnosis, which indicates olfactory test for disease diagnosis has been paid more and more attention. Many researches have indicated olfactory bulb is the first region of the olfactory system to be damaged in AD. AβOs has been confirmed in early olfactory dysfunction in AD, but how the AβOs lead to the olfactory dysfunction is still not exactly realized. Consequently, we chose the OB region as the research object and proposed to establish an olfactory dysfunction model of AD, by the means of a directly electrophysiology method. AβOs-induced olfactory bulb neural network cultured on MEA as dysosmia model of AD at early-stage in vitro is established to investigate that AβOs is detrimental to the processing of olfactory information over time. Firstly, olfactory bulb tissues were extracted and then were digested so that we got the single cell suspension. On the one hand, OB neurons were plated on the surface of MEA chip so that we can detect the extracellular signal in time after AβOs induction. On the other hand, they were cultured on 24-well plate for immunofluorescence to observe the changes of the neuron morphology and cellular proteins. When the OB neural network grew to 13 days, the typical extracellular signals of OB neurons in spontaneous firing state can be recorded. After induced by AβOs, the firing rate of OB neuron disappeared temporarily. After 1 h, the firing rate increased gradually, but after 2 h, the firing rates neurons decreased significantly. Moreover, the firing rate of OB neuron disappeared completely after 3 h. To observe the changes of the cell morphology and cellular proteins after treated with AβOs, we used immunofluorescence method to verify the validity of the dysosmia model in AD. After being induced by AβOs for 3 hours, the neuron plaques increase significantly. This indicates the fact that neurites degeneration and dendrites impairment. As previously described in the mechanics section, phosphorylated tau protein(p-tau) is hyperphosphorylated and abnormally accumulates in Alzheimer’s disease. We performed the staining of p-tau antibody, and analyzed the mean fluorescence intensity to quantify p-tau protein levels. The statistical graph shows the great significant difference between the control and AβOs-treated group. Our results validated that the AβOs can make tau protein phosphorylate, which is similarly to those observed in the degenerating neurons of AD. This also verifies the effectiveness of the model established in this study. Then we try to explain why the spike firing changes after the AβOs induction. When the AβOs was added, it caused N-methyl-D-aspartate (NMDA) receptor and L-type calcium channels opening so that the calcium flew into the cell largely. Eventually, the intracellular calcium overloaded, which then resulted in abnormally improving spontaneous activity. However, the large amount of calcium caused potassium channels opening, and impaired mitochondrial and endoplasmic reticulum (ER) metabolism. Eventually, the whole cellular metabolism disordered, and the neurons became inactive till death. The study will contribute to understanding the cellular and synaptic mechanisms of the early-stage olfactory dysfunction in AD and providing a potential strategy for diagnosis and treatment. And then discuss what it is for and what will we do next by the means of dysosmia model of AD established in the research. Recent study shows that intranasal drug administration is expected to be a targeted therapy method for treating the cerebral diseases. Because it is close to the central nervous system so that the drugs can be transmitted to the cerebral area and be absorbed quickly. Therefore, applying the early-stage dysosmia model of AD to screening the intranasal drug of treating AD is of great significance.

Two-stage culture strategies have been widely applied to improve biomass growth and lipid accumulation in microalgae. Most studies on two-stage culture strategies collect microalgal biomass at the maximum biomass concentration in the first stage and then transfer this biomass into the second stage for subsequent culture. However, there is no scientific conclusion regarding the appropriate time for microalgal biomass collection in the first stage. In this study, the biomass of Chlorella pyrenoidosa was collected at the maximum cell number and maximum biomass concentration in the first stage, and then transferred to the second stage for lipid accumulation. The results show that superior lipid productivity was achieved when using algal cells collected at the maximum cell number than those collected at the maximum biomass concentration. This was due to the strong cell proliferation ability of C. pyrenoidosa at the maximum cell number in the first stage. Moreover, the culture time of the first stage was shortened from 96 h to 48 h for autotrophic culture and 96 h to 60 h for heterotrophic culture. The results presented herein are of great significance for optimizing the current two-stage culture strategies.

A variety of mammalian or insect behaviors rely on the recognition of relevant odor stimuli. The olfactory system detects and translates complex olfactory stimuli (odors) through the unique and reproducible dynamic ensembles of neuronal activities. This process is involved in various types of neurons of olfactory parts, thereby encoding olfactory information or predicting progression in some neuropsychiatric diseases. In this paper, we constructed a biomimetic model including olfactory sensing system and olfactory bulb processing system to map olfactory-associated ensembles of neuronal activity. The olfactory receptor neurons (ORNs) and olfactory bulb (OB) neurons were primarily cultured and the immunofluorescence images were performed to identify the types of neurons. Diacetyl solution was used as an odor stimulus, and the spike bursts and random spike firing patterns of concentration-dependent excitatory responses were obtained from the ORNs network. The spike waveform and feature parameters were extracted including the spike number and interval in per burst to program the stimulation unit and sequences. The sequences containing odor information were applied to the OB neuronal network for the simulation of the primary olfactory processing. The response pattern and change rule of the OB neuronal network were consistent with the OB neurons affected by the neurotransmitter, which is the carrier of olfactory information transmission in vivo. This biomimetic integrated olfactory sensory and processing system can serve as a novel model for studying the physiological and pathological mechanisms of olfaction, and the pharmacological application in vitro.

Aims Diabetes mellitus (DM)-induced reproductive damage is an important cause of infertility for male DM patients, we herein evaluated the effects of catalpol on diabetic reproductive damage through the suppression of the AGEs/RAGE/Nox4 signaling pathway. Methods KK-Ay diabetic reproductive damage mice were administered with catalpol for 8 weeks, the testis/body weight ratio, testicular histopathology, the levels of endogenous hormone and the activity of testicular marker enzymes were determined. In vitro, the GC-2 cell injury model was induced by advanced glycation end-products (AGEs) and pretreated with catalpol. Cell viability, apoptosis, and oxidative stress markers were detected and the mechanism based on the AGEs/RAGE/Nox4 pathway was explored. Key findings Catalpol showed remarkable capacity on protecting diabetic reproductive damage by improving the histomorphology of the testes, increasing the testis/body weight ratio and activity of acid phosphatase (ACP), lactate dehydrogenase (LDH), gamma-glutamyl transferase (γ-GT). The reduced testosterone (T), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in DM mice were also reversed with catalpol intervention. Moreover, catalpol showed markedly effects of anti-oxidative in vivo and in vitro, which significantly down-regulated reactive oxygen species (ROS) levels and restored superoxide dismutase (SOD) activity, meanwhile decreased GC-2 cell apoptosis and Bax/Bcl-2 ratio. Moreover, the over-expression of receptors for AGEs (RAGE), NADPH oxidase type 4 (Nox4) and phosphorylation of nuclear transcription factor-κB p65 (NF-κB p65) were suppressed by catalpol. Significance Catalpol could alleviate DM-induced male reproductive damage by inhibiting oxidative stress-induced apoptosis and inflammation mediated by AGEs/RAGE/Nox4 signaling pathway.

Purpose: To determine the association between Cystatin C (Cys C) levels and the interaction of pulmonary tuberculosis (PTB) with chronic diseases (CD). Methods: Participants ( n = 356) were selected randomly from The First Affiliated Hospital of Wannan Medical College, China, and divided into 4 groups: normal control group ( n = 80), PTB group ( n = 98), chronic disease group ( n = 146), and PTB combined with chronic disease group (PTB+CD, n = 31). The investigation included information on demographics and analysis of blood samples for Cys C, liver function, renal function, blood glucose and other biochemical indices. Results: The highest level of Cys C was obtained in PTB + CD group. Before and after adjusting eGFR, there was no association between Cys C and PTB or/and chronic disease. However abnormal levels of Cys C were significantly higher in PTB+CD group after adjusting eGFR (OR = 4.014, p = 0.0125). Conclusion: Higher levels of Cys C may be associated with chronic diseases co existing with PTB. Keywords: Cystatin C, Pulmonary tuberculosis, Chronic diseases, Inflammation