Genomic investigation of duplication, functional conservation, and divergence in the LRR-RLK Family of Saccharum.

BACKGROUND: Sugarcane (Saccharum spp.) holds exceptional global significance as a vital crop, serving as a primary source of sucrose, bioenergy, and various by-products. The optimization of sugarcane breeding by fine-tuning essential traits has become crucial for enhancing crop productivity and stress resilience. Leucine-rich repeat receptor-like kinases (LRR-RLK) genes present promising targets for this purpose, as they are involved in various aspects of plant development and defense processes. RESULTS: Here, we present a detailed overview of phylogeny and expression of 288 (495 alleles) and 312 (1365 alleles) LRR-RLK genes from two founding Saccharum species, respectively. Phylogenetic analysis categorized these genes into 15 subfamilies, revealing considerable expansion or reduction in certain LRR-type subfamilies. Compared to other plant species, both Saccharum species had more significant LRR-RLK genes. Examination of cis-acting elements demonstrated that SsLRR-RLK and SoLRR-RLK genes exhibited no significant difference in the types of elements included, primarily involved in four physiological processes. This suggests a broad conservation of LRR-RLK gene function during Saccharum evolution. Synteny analysis indicated that all LRR-RLK genes in both Saccharum species underwent gene duplication, primarily through whole-genome duplication (WGD) or segmental duplication. We identified 28 LRR-RLK genes exhibiting novel expression patterns in response to different tissues, gradient development leaves, and circadian rhythm in the two Saccharum species. Additionally, SoLRR-RLK104, SoLRR-RLK7, SoLRR-RLK113, and SsLRR-RLK134 were identified as candidate genes for sugarcane disease defense response regulators through transcriptome data analysis of two disease stresses. This suggests LRR-RLK genes of sugarcane involvement in regulating various biological processes, including leaf development, plant morphology, photosynthesis, maintenance of circadian rhythm stability, and defense against sugarcane diseases. CONCLUSIONS: This investigation into gene duplication, functional conservation, and divergence of LRR-RLK genes in two founding Saccharum species lays the groundwork for a comprehensive genomic analysis of the entire LRR-RLK gene family in Saccharum. The results reveal LRR-RLK gene played a critical role in Saccharum adaptation to diverse conditions, offering valuable insights for targeted breeding and precise phenotypic adjustments.

The effects of laparoscopic and laparotomy extensive hysterectomy on the safety of ureterovaginal fistula infection in patients with cervical cancer.

This study aimed to investigate the effect of laparoscopic and laparotomy extensive hysterectomy on the safety of ureterovaginal fistula infection in patients with cervical cancer. For this purpose, a total of 90 patients with early cervical cancer admitted to Affiliated Huaian No.1 People's Hospital of Nanjing Medical University from February 2021 to May 2022 were randomly divided into laparoscopy group and laparotomy group, with 45 cases in each group. The laparoscopy group was treated with laparoscopic extensive hysterectomy, while the laparotomy group was treated with laparotomy extensive hysterectomy. The KPS score, adverse reactions, as well as serum creatinine and urea nitrogen were compared between the two groups. Results showed that after surgery, the KPS score in both groups was higher than before treatment, and the KPS score in laparoscopy group was higher than that in laparotomy group, the difference was statistically significant (P<0.05). After operation, the incidence of adverse reactions in laparotomy group was higher than that in the laparoscopy group, the difference was statistically significant (P<0.05). Moreover, after operation, the levels of creatinine and urea nitrogen in laparoscopy group were significantly lower than those in laparotomy group, the differences were statistically significant (P<0.05). In conclusion, both laparoscopic and laparotomy extensive hysterectomy may lead to ureterovaginal fistula infection in patients with cervical cancer. However, compared with laparotomy extensive hysterectomy, laparoscopic extensive hysterectomy had higher safety and significantly improved the quality of life of patients, which was worthy of popularization and application in clinical practice.

Soybean glycinin and ß-conglycinin damage the intestinal barrier by triggering oxidative stress and inflammatory response in weaned piglets.

PURPOSE: Soybean glycinin (11S) and ß-conglycinin (7S) are major antigenic proteins in soybean and can induce a variety of allergic reactions in the young animals. This study aimed to investigate the effect of 7S and 11S allergens on the intestine of piglets. METHODS: Thirty healthy 21-day-old weaned "Duroc × Long White × Yorkshire" piglets were randomly divided into three groups fed with the basic diet, the 7S supplemented basic diet, or the 11S supplemented basic diet for 1 week. Allergy markers, intestinal permeability, oxidative stress, and inflammatory reactions were detected, and we observed different sections of intestinal tissue. The expressions of genes and proteins related to NOD-like receptor thermal protein domain associated protein 3 (NLRP-3) signaling pathway were detected by IHC, RT-qPCR, and WB. RESULTS: Severe diarrhea and decreased growth rate were observed in the 7S and 11S groups. Typical allergy markers include IgE production and significant elevations of histamine and 5-hydroxytryptamine (5-HT). More aggressive intestinal inflammation and barrier dysfunction were observed in the experimental weaned piglets. In addition, 7S and 11S supplementation increased the levels of 8-hydroxy-2 deoxyguanosine (8-OHdG) and nitrotyrosine, triggering oxidative stress. Furthermore, higher expression levels of NLRP-3 inflammasome ASC, caspase-1, IL-1ß, and IL-18 were observed in the duodenum, jejunum, and ileum. CONCLUSION: We confirmed that 7S and 11S damaged the intestinal barrier of weaned piglets and may be associated with the onset of oxidative stress and inflammatory response. However, the molecular mechanism underlying these reactions deserves further study.

Murine fertility and spermatogenesis are independent of the testis-specific Spdye4a gene.

BACKGROUND: While many testis-enriched genes have been identified as important regulators of the spermatogenic process, the specific roles played by several of these genes and their functional importance has yet to be fully clarified. METHODS: We employed a CRISPR/Cas9 approach to introduce a 5 bp in-frame deletion within the Spdye4a gene (Exon 2) of C57BL/6 mice (Spdye4a-/-). Fertility and sperm counts were evaluated. Testes tissues and cell suspensions were analyzed via histological and immunofluorescence staining. mRNA and protein levels of candidate genes were assessed through qPCR and Western blotting. In vitro fertilization was used to assess the ability of sperm cells to bind to egg cells. RESULTS: Spdye4a-/- mice did not exhibit any reduction in fertility, and exhibited comparable sperm counts, morphology and motility to those of wildtype littermates. Functionally, Spdye4a-/- sperm exhibited normal sperm-egg binding activity in vitro. Furthermore, the testes of Spdye4a-/- mice exhibited a full range of germ cells from spermatogonia to mature spermatozoa. No differences in the progression of meiotic prophase I were observed when comparing Spdye4a-/- and wildtype mice, indicating that the loss of Spdye4a had no adverse effect on spermatogenesis. DISCUSSION: Spdye4a is dispensable in the context of mice fertility and spermatogenesis. This study will prevent other laboratories from expending repeated efforts to generate similar knockout mice.

Soybean Antigen Protein-Induced Intestinal Barrier Damage by Trigging Endoplasmic Reticulum Stress and Disordering Gut Microbiota in Weaned Piglets.

Endoplasmic reticulum (ER) stress is a crucial factor in the pathogenesis of intestinal diseases. Soybean antigenic proteins (ß-conglycinin and soy glycinin) induce hypersensitivity reactions and intestinal barrier damage. However, whether this damage is associated with ER stress, autophagy, and the gut microbiome is largely unclear. Therefore, in this study, we aimed to investigate the effect of dietary supplementation with soy glycinin (11S glycinin) and ß-conglycinin (7S glycinin) on intestinal ER stress, autophagy, and flora in weaned piglets. Thirty healthy 21-day-old weaned "Duroc × Long White × Yorkshire" piglets were randomly divided into three groups and fed a basic, 7S-supplemented, or 11S-supplemented diet for one week. The results indicated that 7S/11S glycinin disrupted growth performance, damaged intestinal barrier integrity, and impaired goblet cell function in piglets (p < 0.05). Moreover, 7S/11S glycinin induced ER stress and blocked autophagic flux in the jejunum (p < 0.05) and increased the relative abundance of pathogenic flora (p < 0.01) and decreased that of beneficial flora (p < 0.05). In conclusion, 7S/11S glycinin induces intestinal ER stress, autophagic flux blockage, microbiota imbalance, and intestinal barrier damage in piglets.

Population pharmacokinetic and pharmacodynamic analysis of rivaroxaban in Chinese patients with non-valvular atrial fibrillation.

Rivaroxaban, a direct factor Xa inhibitor, is widely used for stroke prevention in patients with non-valvular atrial fibrillation (NVAF). The aim of this study was to conduct a population pharmacokinetic-pharmacodynamic (PK-PD) analysis of rivaroxaban in Chinese patients with NVAF to assess ethnic differences and provide model-based precision dosing. A total of 256 rivaroxaban plasma concentrations and 244 prothrombin time (PT) measurements were obtained from 195 Chinese NVAF patients from a prospective clinical trial. The population PK-PD model was developed using nonlinear mixed effects modeling (NONMEM) software. The PK of rivaroxaban was adequately described using a one-compartment model with first-order adsorption and elimination. Estimated glomerular filtration rate (eGFR) was identified as a major covariate for apparent clearance. No single nucleotide polymorphism was identified as a significant covariate. PT exhibited a linear relationship with rivaroxaban concentration. Total bilirubin (TBIL) and eGFR were identified as significant covariates for baseline PT. According to the Monte Carlo simulation, 15 mg for Chinese patients with eGFR ≥50 mL/min and normal liver function yielded an exposure comparable to 20 mg for Caucasian patients. Patients with moderately impaired renal function may require a lower dose of rivaroxaban to avoid overexposure. Moreover, there was an approximate 26% increase in PT levels in patients with TBIL of 34 µmol/L and eGFR of 30 mL/min, which could increase the risk of major bleeding. The established population PK-PD model could inform individualized dosing for Chinese NVAF patients who are administered rivaroxaban.

Moisture-resistant MXene-sodium alginate sponges with sustained superhydrophobicity for monitoring human activities.

Wearable mechanical sensors are easily influenced by moisture resulting in inaccuracy for monitoring human health and body motions. Though the superhydrophobic barrier has been extensively explored as passive water repel strategy on the sensor surface, the dense superhydrophobic surface not only limits the sensor working under large deformations but also inevitable degradation in high humidity or saturation water vapor environments. This work reports a superhydrophobic MXene-sodium alginate sponge (SMSS) pressure sensor with a low voltage Joule heating effect to provide sustain moisture-insensitive property for both sensing performance and superhydrophobicity by heating-driven water molecules away. Because of the positive temperature coefficient under pressure applied, the Joule heating can provides a stable temperature to the moisture-insensitivity property during the whole dynamic pressure cycled. Therefore, the pressure sensor with a simple spray-coating superhydrophobic coating on the outer layer demonstrates key capabilities even in extreme use scenarios with high humidity or water vapor and also provides stable and reliable bio-signal monitoring.

Epigallocatechin-3-gallate activates the AMP-activated protein kinase signaling pathway to reduce lipid accumulation in canine hepatocytes.

Epigallocatechin-3-gallate (EGCG) plays a crucial role in hepatic lipid metabolism. However, the underlying regulatory mechanism of hepatic lipid metabolism by EGCG in canine is unclear. Primary canine hepatocytes were treated with EGCG (0.01, 0.1, or 1 µM) and BML-275 (an AMP-activated protein kinase [AMPK] inhibitor) to study the effects of EGCG on the gene and protein expressions associated with AMPK signaling pathway. Data showed that treatment with EGCG had greater activation of AMPK, as well as greater expression levels and transcriptional activity of peroxisome proliferator activated receptor-α (PPARα) along with upregulated messenger RNA (mRNA) abundance and protein abundance of PPARα-target genes. EGCG decreased the expression levels and transcriptional activity of sterol regulatory element-binding protein 1c (SREBP-1c) along with downregulated mRNA abundance and protein abundance of SREBP-1c target genes. Of particular interest, exogenous BML-275 could reduce or eliminate the effects of EGCG on lipid metabolism in canine hepatocytes. Furthermore, the content of triglyceride was significantly decreased in the EGCG-treated groups. These results suggest that EGCG might be a potential agent in preventing high-fat diet-induced lipid accumulation in small animals.

Genome-wide analysis of R2R3-MYB transcription factors family in the autopolyploid Saccharum spontaneum: an exploration of dominance expression and stress response.

BACKGROUND: Sugarcane (Saccharum) is the most critical sugar crop worldwide. As one of the most enriched transcription factor families in plants, MYB genes display a great potential to contribute to sugarcane improvement by trait modification. We have identified the sugarcane MYB gene family at a whole-genome level through systematic evolution analyses and expression profiling. R2R3-MYB is a large subfamily involved in many plant-specific processes. RESULTS: A total of 202 R2R3-MYB genes (356 alleles) were identified in the polyploid Saccharum spontaneum genomic sequence and classified into 15 subgroups by phylogenetic analysis. The sugarcane MYB family had more members by a comparative analysis in sorghum and significant advantages among most plants, especially grasses. Collinearity analysis revealed that 70% of the SsR2R3-MYB genes had experienced duplication events, logically suggesting the contributors to the MYB gene family expansion. Functional characterization was performed to identify 56 SsR2R3-MYB genes involved in various plant bioprocesses with expression profiling analysis on 60 RNA-seq databases. We identified 22 MYB genes specifically expressed in the stem, of which RT-qPCR validated MYB43, MYB53, MYB65, MYB78, and MYB99. Allelic expression dominance analysis implied the differential expression of alleles might be responsible for the high expression of MYB in the stem. MYB169, MYB181, MYB192 were identified as candidate C4 photosynthetic regulators by C4 expression pattern and robust circadian oscillations. Furthermore, stress expression analysis showed that MYB36, MYB48, MYB54, MYB61 actively responded to drought treatment; 19 and 10 MYB genes were involved in response to the sugarcane pokkah boeng and mosaic disease, respectively. CONCLUSIONS: This is the first report on genome-wide analysis of the MYB gene family in sugarcane. SsMYBs probably played an essential role in stem development and the adaptation of various stress conditions. The results will provide detailed insights and rich resources to understand the functional diversity of MYB transcription factors and facilitate the breeding of essential traits in sugarcane.

Role of RNA Oxidation in Neurodegenerative Diseases.

In the history of nucleic acid research, DNA has always been the main research focus. After the sketch of the human genome was completed in 2000, RNA has been started to gain more attention due to its abundancies in the cell and its essential role in cellular physiology and pathologies. Recent studies have shown that RNAs are susceptible to oxidative damage and oxidized RNA is able to break the RNA strand, and affect the protein synthesis, which can lead to cell degradation and cell death. Studies have shown that RNA oxidation is one of the early events in the formation and development of neurodegenerative disorders, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. However, its molecular mechanism, as well as its impact on these diseases, are still unclear. In this article, we review the different types of RNA oxidative damage and the neurodegenerative diseases that are reported to be associated with RNA oxidative damage. In addition, we discuss recent findings on the association between RNA oxidative damage and the development of neurodegenerative diseases, which will have great significance for the development of novel strategies for the prevention and treatment of these diseases.

Glucagon attenuates lipid accumulation in cow hepatocytes through AMPK signaling pathway activation.

The ketotic cows displayed hepatic lipid metabolic disorder and high blood concentration of glucagon. Importantly, adenosine monophosphate-activated protein kinase (AMPK) signaling pathway plays an important role in the hepatic lipid homeostasis. Therefore, the aim of this study was to investigate the effect of glucagon on AMPK pathway and its underlying mechanism on lipid metabolism in cow hepatocytes. Cow hepatocytes were cultured and treated with glucagon and AMPK inhibitor (BML-275). The results showed that glucagon significantly promoted the expression of glucagon receptor and increased the phosphorylation level and activity of AMPKα. Activated AMPKα increased the expression level and transcriptional activity of peroxisome proliferator-activated receptor α, which further increased the expression of fatty acid oxidation genes and lipid oxidation. Furthermore, activated AMPKα inhibited the expression level and transcriptional activity of sterol regulatory element binding protein-1c and carbohydrate response element binding protein, which decreased the expression of lipogenic genes, thereby decreasing lipid synthesis. In addition, glucagon also increased the expression of very-low-density lipoprotein (VLDL) assembly to export intracellular triglycerides (TG). Consequently, the content of intracellular TG was significantly decreased in cow hepatocytes. These results indicate that glucagon activates the AMPK signaling pathway to increase lipid oxidation and VLDL assembly and decrease lipid synthesis in cow hepatocytes, thereby reducing liver fat accumulation.

Highly glycosylated CD147 promotes hemorrhagic transformation after rt-PA treatment in diabetes: a novel therapeutic target?

BACKGROUND: Diabetes is known to be a main risk factor of post-stroke hemorrhagic transformation following recombinant tissue plasminogen activator (rt-PA) therapy. However, the mechanism through which diabetes exacerbates hemorrhagic transformation is insufficiently understood. We aimed to verify that CD147, the extracellular matrix metalloproteinase (MMP) inducer, played a vital role in the progress. METHODS: We performed middle cerebral artery occlusion on diabetic and non-diabetic rats, with or without rt-PA treatment, and then compared the glycosylation level of CD147, caveolin-1, MMPs activities, and blood-brain barrier (BBB) permeability. In vitro, tunicamycin treatment and genetic tools were used to produce non-glycosylated and lowly glycosylated CD147. An endogenous glucagon-like peptide-1 receptor (GLP-1R) agonist was used to downregulate the glycosylation of CD147 in vivo. RESULTS: Compared with non-diabetic rats, diabetic rats expressed higher levels of highly glycosylated CD147 in endothelium and astrocytes following rt-PA treatment accompanied by higher activity of MMPs and BBB permeability, in the middle cerebral artery occlusion model. Caveolin-1 was also overexpressed and co-localized with CD147 in astrocytes and endothelium in diabetic rats. In vitro, advanced glycation end products increased the expression of highly glycosylated CD147 in astrocytes and endothelial cells. Downregulating the glycosylation of CD147 lowered the activity of MMPs and promoted the expression of tight junction proteins. The expression of caveolin-1 in endothelial cells and astrocytes was not inhibited by tunicamycin, which revealed that caveolin-1 was an upstream of CD147. In vivo, GLP-1R agonist downregulated the glycosylation of CD147 and further reduced the activity of MMPs and protected the BBB in diabetic rats. CONCLUSION: CD147 is essential for diabetes-associated rt-PA-induced hemorrhagic transformation, and downregulation of CD147 glycosylation is a promising therapy for neurovascular-unit repair after rt-PA treatment of patients with diabetes.

Rutin protects against lipopolysaccharide-induced mastitis by inhibiting the activation of the NF-κB signaling pathway and attenuating endoplasmic reticulum stress.

Rutin, found widely in traditional Chinese medicine materials, is used to treat eye swelling and pain, hypertension, and hyperlipidemia. In the present study, a mouse mastitis model induced by lipopolysaccharide (LPS) was established to explore rutin's inhibitory mechanism on mastitis via nuclear factor kappa B (NF-κB) inflammatory signaling and the relationship between NF-κB signaling and endoplasmic reticulum (ER) stress. Mice were divided into six groups: Control group, LPS model group, LPS + rutin (25, 50, and 100 mg/kg) and LPS + dexamethasone (DEX) group. DEX, rutin, and PBS (control and LPS groups) were administered 1 h before and 12 h after perfusion of LPS. After LPS stimulation for 24 h, to evaluate rutin's therapeutic effect on mastitis, the mammary tissues of each group were collected to detect histopathological injury, tumor necrosis factor alpha (TNF-α), interleukin (IL)-1ß, and IL-6 mRNA and protein levels; and glucose-regulated protein, 78 kDa (GRP78) protein levels. The protein and mRNA levels of TNF-α, IL-1ß, and IL-6 in the LPS + rutin group were significantly lower than those in the LPS model group. Similarly, p50/p105, phosphorylated (p)-p65/p65 and p-inhibitor of nuclear factor kappa b kinase subunit beta (p-IKKß)/IKKß ratios in the LPS + rutin group (50 mg/kg) and LPS + rutin group (100 mg/kg) decreased significantly. GRP78 protein expression was significantly higher in LPS + rutin group (100 mg/kg). The structure of mammary tissue became gradually more intact and vacuolization of acini decreased as the rutin concentration increased. The nuclear quantity of p65 in the LPS + rutin group decreased significantly in a rutin dose-dependent manner. Rutin had an anti-inflammatory effect in the LPS-induced mouse mastitis model, manifested by inhibition of NF-κB pathway activation and attenuation of ER stress.

Insulin suppresses the AMPK signaling pathway to regulate lipid metabolism in primary cultured hepatocytes of dairy cows.

Dairy cows with type II ketosis display hepatic fat accumulation and hyperinsulinemia, but the underlying mechanism is not completely clear. This study aimed to clarify the regulation of lipid metabolism by insulin in cow hepatocytes. In vitro, cow hepatocytes were treated with 0, 1, 10, or 100 nm insulin in the presence or absence of AICAR (an AMP-activated protein kinase alpha (AMPKα) activator). The results showed that insulin decreased AMPKα phosphorylation. This inactivation of AMPKα increased the gene and protein expression levels of carbohydrate responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein-1c (SREBP-1c), which downregulated the expression of lipogenic genes, thereby decreasing lipid biosynthesis. Furthermore, AMPKα inactivation decreased the gene and protein expression levels of peroxisome proliferator-activated receptor-α (PPARα), which upregulated the expression of lipid oxidation genes, thereby increasing lipid oxidation. In addition, insulin decreased the very low density lipoprotein (VLDL) assembly. Consequently, triglyceride content was significantly increased in insulin treated hepatocytes. Activation of AMPKα induced by AICAR could reverse the effect of insulin on PPARα, SREBP-1c, and ChREBP, thereby decreasing triglyceride content. These results indicate that insulin inhibits the AMPKα signaling pathway to increase lipid synthesis and decrease lipid oxidation and VLDL assembly in cow hepatocytes, thereby inducing TG accumulation. This mechanism could partly explain the causal relationship between hepatic fat accumulation and hyperinsulinemia in dairy cows with type II ketosis.

The glucagon-like peptide-1 receptor agonist exendin-4 ameliorates warfarin-associated hemorrhagic transformation after cerebral ischemia.

BACKGROUND: As the number of patients with cardioembolic ischemic stroke is predicted to be double by 2030, increased burden of warfarin-associated hemorrhagic transformation (HT) after cerebral ischemia is an expected consequence. However, thus far, no effective treatment strategy is available for HT prevention in routine clinical practice. While the glucagon-like peptide-1 receptor (GLP-1R) agonist exendin-4 (Ex-4) is known to protect against oxidative stress and neuronal cell death caused by ischemic brain damage, its effect on preventing warfarin-associated HT after cerebral ischemia is yet unknown. Therefore, we hypothesized that Ex-4 would stabilize the blood-brain barrier (BBB) and suppress neuroinflammation through PI3K-Akt-induced inhibition of glycogen synthase kinase-3ß (GSK-3ß) after warfarin-associated HT post-cerebral ischemia. METHODS: We used male C57BL/6 mice for all experiments. A 5-mg warfarin sodium tablet was dissolved in animals' drinking water (effective warfarin uptake 0.04 mg (2 mg/kg) per mouse). The mice were fed for 0, 6, 12, and 24 h with ad libitum access to the treated water. To study the effects of Ex-4, temporary middle cerebral artery occlusion (MCAO) was performed. Then, either Ex-4 (10 mg/kg) or saline was injected through the tail vein, and in the Ex-4 + wortmannin group, PI3K inhibitor wortmannin was intravenously injected, after reperfusion. The infarct volume, neurological deficits, and integrity of the BBB were assessed 72 h post MCAO. One- or two-way ANOVA was used to test the difference between means followed by Newman-Keuls post hoc testing for pair-wise comparison. RESULTS: We observed that Ex-4 ameliorated warfarin-associated HT and preserved the integrity of the BBB after cerebral ischemia through the PI3K/Akt/GSK-3ß pathway. Furthermore, Ex-4 suppressed oxidative DNA damage and lipid peroxidation, attenuated pro-inflammatory cytokine expression levels, and suppressed microglial activation and neutrophil infiltration in warfarin-associated HT post-cerebral ischemia. However, these effects were totally abolished in the mice treated with Ex-4 + the PI3K inhibitor-wortmannin. The PI3K/Akt-GSK-3ß signaling pathway appeared to contribute to the protection afforded by Ex-4 in the warfarin-associated HT model. CONCLUSIONS: GLP-1 administration could reduce warfarin-associated HT in mice. This beneficial effect of GLP-1 is associated with attenuating neuroinflammation and BBB disruption by inactivating GSK-3ß through the PI3K/Akt pathway.

Preparation and Biocompatibility of Gold@ Polypyrrole-Chitosan with Core-Shell Nanostructure.

A two-step method for preparing Au@polypyrrole-chitosan core-shell nanoparticles (Au @ PPy-CS NPs) was fabricated by in situ polymerization of pyrrole monomer on the surface of Au spheres in chitosan solution. Transmission electron microscopy (TEM) images showed the presence of core-shell structure of nanoparticles. Energy-Dispersive Spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy were adopted to verify the shell is polypyrrole-chitosan. Ultraviolet-visible (UV-vis) and X-ray diffraction (XRD) showed that Au was present in the core-shell nanoparticles. The biocompatibility of Au @ PPy-CS NPs was characterized by in vitro for hemolysis assay and cytotoxicity experiments. Results indicated the Au @ PPy-CS NPs had good blood compatibility and low cytotoxicity. The Au @ PPy-CS NPs we proposed provide a promising platform of blood circulation system for early illness diagnosis and therapy.

High levels of acetoacetate and glucose increase expression of cytokines in bovine hepatocytes, through activation of the NF-κB signalling pathway.

Elevated levels of blood interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) increase insulin resistance and result in inflammation. It is not clear whether elevated blood level of acetoacetate (ACAC) and decreased blood level of glucose, which are the predominant characteristics of clinical biochemistry in ketotic dairy cows, increase proinflammatory cytokines and subsequent inflammation. The objective of this study was to test the hypothesis that ACAC and glucose activate the NF-κB signalling pathway to regulate cytokines expression in bovine hepatocytes. Bovine hepatocytes were cultured with ACAC (0-4.8 mm) and glucose (0-5.55 mm) with or without NF-κB inhibitor PDTC for 24 h. The secretion and mRNA levels of cytokines were determined by enzyme-linked immunosorbent assay (ELISA) and real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). The NF-κB signalling pathway activation was evaluated by western blotting. Results showed that the secretion and expression of IL-1ß, IL-6 and TNF-α increased in an ACAC dose-dependent manner. Additionally, there was an increase in the secretion and mRNA expression of these three cytokines in glucose treatment group, which increased significantly when the glucose concentrations exceed 3.33 mm. Furthermore, both ACAC and glucose upregulated NF-κB p65 protein expression and IκBα phosphorylation levels. However, these effects were reduced by PDTC. These results demonstrate that elevated levels of ACAC and glucose increase the synthesis and expression of proinflammatory factors by activating NF-κB signalling pathway in hepatocytes, which may contribute to inflammation injury in ketotic dairy cows.

Aquaporin-4 and Cerebrovascular Diseases.

Cerebrovascular diseases are conditions caused by problems with brain vasculature, which have a high morbidity and mortality. Aquaporin-4 (AQP4) is the most abundant water channel in the brain and crucial for the formation and resolution of brain edema. Considering brain edema is an important pathophysiological change after stoke, AQP4 is destined to have close relation with cerebrovascular diseases. However, this relation is not limited to brain edema due to other biological effects elicited by AQP4. Till now, multiple studies have investigated roles of AQP4 in cerebrovascular diseases. This review focuses on expression of AQP4 and the effects of AQP4 on brain edema and neural cells injuries in cerebrovascular diseases including cerebral ischemia, intracerebral hemorrhage and subarachnoid hemorrhage. In the current review, we pay more attention to the studies of recent years directly from cerebrovascular diseases animal models or patients, especially those using AQP4 gene knockout mice. This review also elucidates the potential of AQP4as an excellent therapeutic target.

Erythropoietin protects against hemorrhagic blood-brain barrier disruption through the effects of aquaporin-4.

Erythropoietin (EPO) has protective effects against many neurological diseases, including intracerebral hemorrhage (ICH). Here, we aimed to test EPO's effects on blood-brain barrier (BBB) disruption morphologically and functionally following ICH, which has not been well investigated. We also examined whether the effects were dependent on aquaporin-4 (AQP4). We detected the expression of perihematomal AQP4 and EPO receptor (EPOR) induced by EPO injection at 1, 3 and 7 days after ICH. We also examined the effects of EPO on BBB disruption by ICH in wild-type mice, and tested whether such effects were AQP4 dependent by using AQP4 knock-out mice. Furthermore, we assessed the related signal transduction pathways via astrocyte cultures. We found that EPO highly increased perihematomal AQP4 and EPOR expression. Specifically, EPO led to BBB protection in both types of mice by functionally reducing brain edema and BBB permeability, as well as morphologically suppressing tight junction (TJ) opening and endothelial cell swelling, and increasing expression of the TJ proteins occludin and zonula occluden-1 (ZO-1). Statistical analysis indicated that AQP4 was required for these effects. In addition, EPO upregulated phosphorylation of C-Jun amino-terminal kinase (JNK) and p38-mitogen-activated protein kinase (MAPK) as well as EPOR and AQP4 proteins in cultured astrocytes. The latter was inhibited by JNK and p38-MAPK inhibitors. Our data suggest that EPO protects BBB from disruption after ICH and that the main targets are the TJ proteins occludin and ZO-1. The effects of EPO are associated with increased levels of AQP4, and may occur through activation of JNK and p38-MAPK pathways after binding to EPOR.

Non-esterified fatty acids activate the ROS-p38-p53/Nrf2 signaling pathway to induce bovine hepatocyte apoptosis in vitro.

A high plasma concentration of non-esterified fatty acids (NEFAs) is an important pathogenic factor that leads to ketosis and fatty liver in dairy cows. NEFAs may be associated with oxidative stress in dairy cows with ketosis or fatty liver and the subsequent induction of hepatocyte damage. However, the molecular mechanism of NEFAs-induced oxidative stress and whether NEFAs cause apoptosis of hepatocytes are unclear. Therefore, the aim of this study was to investigate the molecular mechanism of NEFAs-induced oxidative liver damage in bovine hepatocytes. The results showed that NEFAs increased oxidative stress, resulting in p38 phosphorylation. High activated p38 increased the expression, nuclear localization and transcriptional activity of p53 and decreased the nuclear localization and transcriptional activity of Nrf2 in bovine hepatocytes treated with high concentrations of NEFAs. High concentrations of NEFAs also promoted the apoptosis of bovine hepatocytes. Both N-acetyl-L-cysteine (NAC) and glucose (GLU) could attenuate the NEFA-induced apoptotic damage. These results indicate that NEFAs activate the ROS-p38-p53/Nrf2 signaling pathway to induce apoptotic damage in bovine hepatocytes.