Establishment and application of a reverse dot blot assay for 13 mutations of hearing-loss genes in primary hospitals in China.

Background: Hearing loss is a common sensorineural dysfunction with a high incidence in China. Although genetic factors are important causes of hearing loss, hearing-related gene detection has not been widely adopted in China. Objective: Establishing a rapid and efficient method to simultaneously detect hotspot hearing loss gene mutations. Methods: A reverse dot blot assay combined with a flow-through hybridization technique was developed for the simultaneous detection of 13 hotspot mutations of 4 hearing loss-related genes including GJB2, GJB3, SLC26A4, and the mitochondrial gene MT-RNR1. This method involved PCR amplification systems and a hybridization platform. Results: The technique can detect 13 hotspot mutations of 4 hearing loss-related genes. And a total of 213 blood samples were used to evaluate the availability of this method. Discussion: Our reverse dot blot assay was a simple, rapid, accurate, and cost-effective method to identify hotspot mutations of 4 hearing loss-related genes in a Chinese population.

KCNH6 is essential for insulin secretion by regulating intracellular ER Ca2+ store.

Appropriate Ca2+ concentration in the endoplasmic reticulum (ER), modulating cytosolic Ca2+ signal, serves significant roles in physiological function of pancreatic ß cells. To maintaining ER homeostasis, Ca2+ movement across the ER membrane is always accompanied by a simultaneous K+ flux in the opposite direction. KCNH6 was proven to modulate insulin secretion by controlling plasma membrane action potential duration and intracellular Ca2+ influx. Meanwhile, the specific function of KCNH6 in pancreatic ß-cells remains unclear. In this study, we found that KCNH6 exhibited mainly ER localization and Kcnh6 ß-cell-specific knockout (ßKO) mice suffered from abnormal glucose tolerance and impaired insulin secretion in adulthood. ER Ca2+ store was overloaded in islets of ßKO mice, which contributed to ER stress and ER stress-induced apoptosis in ß cells. Next, we verified that ethanol treatment induced increases in ER Ca2+ store and apoptosis in pancreatic ß cells, whereas adenovirus-mediated KCNH6 overexpression in islets attenuated ethanol-induced ER stress and apoptosis. In addition, tail-vein injections of KCNH6 lentivirus rescued KCNH6 expression in ßKO mice, restored ER Ca2+ overload and attenuated ER stress in ß cells, which further confirms that KCNH6 protects islets from ER stress and apoptosis. These data suggest that KCNH6 on the ER membrane may help to stabilize intracellular ER Ca2+ stores and protect ß cells from ER stress and apoptosis. In conclusion, our study reveals the protective potential of KCNH6-targeting drugs in ER stress-induced diabetes.

All-potassium channel CRISPR screening reveals a lysine-specific pathway of insulin secretion.

OBJECTIVE: Genome-scale CRISPR-Cas9 knockout coupled with single-cell RNA sequencing (scRNA-seq) has been used to identify function-related genes. However, this method may knock out too many genes, leading to low efficiency in finding genes of interest. Insulin secretion is controlled by several electrophysiological events, including fluxes of KATP depolarization and K+ repolarization. It is well known that glucose stimulates insulin secretion from pancreatic ß-cells, mainly via the KATP depolarization channel, but whether other nutrients directly regulate the repolarization K+ channel to promote insulin secretion is unknown. METHODS: We used a system involving CRISPR-Cas9-mediated knockout of all 83 K+ channels and scRNA-seq in a pancreatic ß cell line to identify genes associated with insulin secretion. RESULTS: The expression levels of insulin genes were significantly increased after all-K+ channel knockout. Furthermore, Kcnb1 and Kcnh6 were the two most important repolarization K+ channels for the increase in high-glucose-dependent insulin secretion that occurred upon application of specific inhibitors of the channels. Kcnh6 currents, but not Kcnb1 currents, were reduced by one of the amino acids, lysine, in both transfected cells, primary cells and mice with ß-cell-specific deletion of Kcnh6. CONCLUSIONS: Our function-related CRISPR screen with scRNA-seq identifies Kcnh6 as a lysine-specific channel.

Disturbed Flow-Facilitated Margination and Targeting of Nanodisks Protect against Atherosclerosis.

Disturbed blood flow induces endothelial pro-inflammatory responses that promote atherogenesis. Nanoparticle-based therapeutics aimed at treating endothelial inflammation in vasculature where disturbed flow occurs may provide a promising avenue to prevent atherosclerosis. By using a vertical-step flow apparatus and a microfluidic chip of vascular stenosis, herein, it is found that the disk-shaped versus the spherical nanoparticles exhibit preferential margination (localization and adhesion) to the regions with the pro-atherogenic disturbed flow. By employing a mouse model of carotid partial ligation, superior targeting and higher accumulation of the disk-shaped particles are also demonstrated within disturbed flow areas than that of the spherical particles. In hyperlipidemia mice, administration of disk-shaped particles loaded with hypomethylating agent decitabine (DAC) displays greater anti-inflammatory and anti-atherosclerotic effects compared with that of the spherical counterparts and exhibits reduced toxicity than "naked" DAC. The findings suggest that shaping nanoparticles to disk is an effective strategy for promoting their delivery to atheroprone endothelia.

Cisapride induced hypoglycemia via the KCNH6 potassium channel.

Mutations in KCNH6 has been proved to cause hypoinsulinemia and diabetes in human and mice. Cisapride is a stomach-intestinal motility drug used to treat gastrointestinal dysfunction. Cisapride has been reported to be a potential inhibitor of the KCNH family, but it remained unclear whether cisapride inhibited KCNH6. Here, we discovered the role of cisapride on glucose metabolism, focusing on the KCNH6 potassium channel protein. Cisapride reduced blood glucose level and increased serum insulin secretion in wild-type (WT) mice fed standard normal chow/a high-fat diet or in db/db mice, especially when combined with tolbutamide. This effect was much stronger after 4 weeks of intraperitoneal injection. Whole-cell patch-clamp showed that cisapride inhibited KCNH6 currents in transfected HEK293 cells in a concentration-dependent manner. Cisapride induced an increased insulin secretion through the disruption of intracellular calcium homeostasis in a rat pancreatic ß-cell line, INS-1E. Further experiments revealed that cisapride did not decrease blood glucose or increase serum insulin in KCNH6 ß-cell knockout (Kcnh6-ß-KO) mice when compared with WT mice. Cisapride also ameliorated glucose-stimulated insulin secretion (GSIS) in response to high glucose in WT but not Kcnh6-ß-KO mice. Thus, our data reveal a novel way for the effect of KCNH6 in cisapride-induced hypoglycemia.

KCNH6 Enhanced Hepatic Glucose Metabolism through Mitochondrial Ca2+ Regulation and Oxidative Stress Inhibition.

KCNH6 has been proven to affect glucose metabolism and insulin secretion both in humans and mice. Further study revealed that Kcnh6 knockout (KO) mice showed impaired glucose tolerance. However, the precise function of KCNH6 in the liver remains unknown. Mitochondria have been suggested to maintain intracellular Ca2+ homeostasis; ROS generation and defective mitochondria can cause glucose metabolism disorders, including type 2 diabetes (T2D). Here, we found that Kcnh6 attenuated glucose metabolism disorders by decreasing PEPCK and G6pase abundance and induced Glut2 and IRS2 expression. Overexpression of Kcnh6 increased hepatic glucose uptake and glycogen synthesis. Kcnh6 attenuated intracellular and mitochondrial calcium levels in primary hepatocytes and reduced intracellular ROS and mitochondrial superoxide production. Kcnh6 suppressed oxidative stress by inhibiting mitochondrial pathway activation and NADPH oxidase expression. Experiments demonstrated that Kcnh6 expression improved hepatic glucose metabolism disorder through the c-Jun N-terminal kinase and p38MAPK signaling pathways. These results were confirmed by experiments evaluating the extent to which forced Kcnh6 expression rescued metabolic disorder in KO mice. In conclusion, KCNH6 enhanced hepatic glucose metabolism by regulating mitochondrial Ca2+ levels and inhibiting oxidative stress. As liver glucose metabolism is key to T2D, understanding KCNH6 functions may provide new insights into the causes of diabetes.

Effects of Umbilical Cord Milking on Anemia in Preterm Infants: A Multicenter Randomized Controlled Trial.

OBJECTIVE: This study aimed to investigate whether umbilical cord milking (UCM) prevents and controls anemia in preterm infants, as compared with immediate cord clamping (ICC). STUDY DESIGN: Pregnant women delivering at <34 weeks' gestation in four hospitals were randomly assigned to undergo UCM or ICC from July 2017 to June 2019. Hematological parameters and iron status were collected and analyzed as primary outcomes at 24 hours, 1 week, 2 weeks, and 6 months after delivery. RESULTS: Neonates receiving UCM had significant higher levels of hemoglobin (Hb), hematocrit, and serum iron (p < 0.05). Lower prevalence of anemia and lower need for transfusions were noted in UCM group. Although UCM was associated with prolonged duration of phototherapy, the maximum levels of bilirubin were similar between two groups (p > 0.05). CONCLUSION: UCM is an effective intervention to help preterm infants experience less anemia with the potential to increase blood volume, as seen by higher Hb levels and more enhanced iron stores.

Association Analysis Between HLA-DQA1 Loci and Neuromyelitis Optica Spectrum Disorder in a Han Chinese Population.

BACKGROUND: Genome-wide association studies for neuromyelitis optica spectrum disorder (NMOSD) have established an association between HLA-DQ alpha 1 (DQA1) and risk for NMOSD. Though ethnicity is generally considered a major influencing factor in genetic analyses, little is known regarding the association of HLA-DQA1 polymorphisms with NMOSD in the Han population, especially the single-nucleotide polymorphisms (SNPs) at HLA-DQA1 . METHODS: We genotyped SNP at loci rs28383224 in a case-control study consisting of 137 subjects (51 patients with NMOSD and 86 unrelated controls were recruited) of Han ethnicity. Logistic regression was used to test the association of SNP with NMOSD susceptibility, the sex and age were adjusted, odds ratios and 95% confidence intervals were estimated. RESULTS: The rs28383224 polymorphism and susceptibility to NMOSD were not statistically associated ( P >0.05) in the Han population in the current study. No significant difference was found in allelic frequencies or genotypic distributions among different subsets of NMOSD patients ( P >0.05). CONCLUSION: In the current study, there is no evidence that polymorphism of rs28383224 in the HLA-DQA1 gene is associated with the risk of NMOSD in the Han Chinese population.

Transforming growth factor beta-1 upregulates glucose transporter 1 and glycolysis through canonical and noncanonical pathways in hepatic stellate cells.

BACKGROUND: Hepatic stellate cells (HSCs) are the key effector cells mediating the occurrence and development of liver fibrosis, while aerobic glycolysis is an important metabolic characteristic of HSC activation. Transforming growth factor-ß1 (TGF-ß1) induces aerobic glycolysis and is a driving factor for metabolic reprogramming. The occurrence of glycolysis depends on a high glucose uptake level. Glucose transporter 1 (GLUT1) is the most widely distributed glucose transporter in the body and mainly participates in the regulation of carbohydrate metabolism, thus affecting cell proliferation and growth. However, little is known about the relationship between TGF-ß1 and GLUT1 in the process of liver fibrosis and the molecular mechanism underlying the promotion of aerobic glycolysis in HSCs. AIM: To investigate the mechanisms of action of GLUT1, TGF-ß1 and aerobic glycolysis in the process of HSC activation during liver fibrosis. METHODS: Immunohistochemical staining and immunofluorescence assays were used to examine GLUT1 expression in fibrotic liver tissue. A Seahorse extracellular flux (XF) analyzer was used to examine changes in aerobic glycolytic flux, lactate production levels and glucose consumption levels in HSCs upon TGF-ß1 stimulation. The mechanism by which TGF-ß1 induces GLUT1 protein expression in HSCs was further explored by inhibiting/promoting the TGF-ß1/mothers-against-decapentaplegic-homolog 2/3 (Smad2/3) signaling pathway and inhibiting the p38 and phosphoinositide 3-kinase (PI3K)/AKT signaling pathways. In addition, GLUT1 expression was silenced to observe changes in the growth and proliferation of HSCs. Finally, a GLUT1 inhibitor was used to verify the in vivo effects of GLUT1 on a mouse model of liver fibrosis. RESULTS: GLUT1 protein expression was increased in both mouse and human fibrotic liver tissues. In addition, immunofluorescence staining revealed colocalization of GLUT1 and alpha-smooth muscle actin proteins, indicating that GLUT1 expression was related to the development of liver fibrosis. TGF-ß1 caused an increase in aerobic glycolysis in HSCs and induced GLUT1 expression in HSCs by activating the Smad, p38 MAPK and P13K/AKT signaling pathways. The p38 MAPK and Smad pathways synergistically affected the induction of GLUT1 expression. GLUT1 inhibition eliminated the effect of TGF-ß1 on HSC proliferation and migration. A GLUT1 inhibitor was administered in a mouse model of liver fibrosis, and GLUT1 inhibition reduced the degree of liver inflammation and liver fibrosis. CONCLUSION: TGF-ß1 induces GLUT1 expression in HSCs, a process related to liver fibrosis progression. In vitro experiments revealed that TGF-ß1-induced GLUT1 expression might be one of the mechanisms mediating the metabolic reprogramming of HSCs. In addition, in vivo experiments also indicated that the GLUT1 protein promotes the occurrence and development of liver fibrosis.

Vitexin inhibits APEX1 to counteract the flow-induced endothelial inflammation.

Vascular endothelial cells are exposed to shear stresses with disturbed vs. laminar flow patterns, which lead to proinflammatory vs. antiinflammatory phenotypes, respectively. Effective treatment against endothelial inflammation and the consequent atherogenesis requires the identification of new therapeutic molecules and the development of drugs targeting these molecules. Using Connectivity Map, we have identified vitexin, a natural flavonoid, as a compound that evokes the gene-expression changes caused by pulsatile shear, which mimics laminar flow with a clear direction, vs. oscillatory shear (OS), which mimics disturbed flow without a clear direction. Treatment with vitexin suppressed the endothelial inflammation induced by OS or tumor necrosis factor-α. Administration of vitexin to mice subjected to carotid partial ligation blocked the disturbed flow-induced endothelial inflammation and neointimal formation. In hyperlipidemic mice, treatment with vitexin ameliorated atherosclerosis. Using SuperPred, we predicted that apurinic/apyrimidinic endonuclease1 (APEX1) may directly interact with vitexin, and we experimentally verified their physical interactions. OS induced APEX1 nuclear translocation, which was inhibited by vitexin. OS promoted the binding of acetyltransferase p300 to APEX1, leading to its acetylation and nuclear translocation. Functionally, knocking down APEX1 with siRNA reversed the OS-induced proinflammatory phenotype, suggesting that APEX1 promotes inflammation by orchestrating the NF-κB pathway. Animal experiments with the partial ligation model indicated that overexpression of APEX1 negated the action of vitexin against endothelial inflammation, and that endothelial-specific deletion of APEX1 ameliorated atherogenesis. We thus propose targeting APEX1 with vitexin as a potential therapeutic strategy to alleviate atherosclerosis.

[Effects of potassium-solubilizing bacteria promoting the growth of Lycium barbarum seedlings under salt stress.] / 盐胁迫下解钾菌对枸杞幼苗的促生效应.

We investigated the effects of potassium-releasing bacteria on physiological and bioche-mical characteristics of Lycium barbarum (Cultivar Ningqi 1) under salt stress, with an experiment with treatments following randomized block design. The treatments included control (CK), 100 mmol·L-1 NaCl stress (NaCl), 100 mmol·L-1NaCl stress+KSBGY01 bacteria (NaCl-M1), 100 mmol·L-1NaCl stress+KSBGY02 bacteria (NaCl-M2), and 100 mmol·L-1NaCl stress+KSBGY01+KSBGY02 (NaCl-M3). We measued chlorophyll content, polyphenol content, superoxide anion (O2-·) content, hydrogen peroxide (H2O2) content, soluble sugar content, antioxidant enzyme activity and sucrose metabolic enzyme activity of Lycium barbarum seedlings. Results showed that the presence of potassium bacteria increased the values of flavonoids (FLAV), fluorescence excitation than anthocyanins relative index (FERARI), anthocyanins (ANTH-RB), nitrogen balance index (NBI-G), decreased the contents of O2-· and H2O2, and improved soluble sugar content, catalase (CAT) activity, sucrose phosphate synthase (SPS) activity, sucrose synthase (SS) activity and invertase (INV) activity of leaves in Lycium barbarum seedlings under salt stress. Among all the treatments, the highest values of ANTH-RB and NBI-G, soluble sugar content, and activities of CAT, SPS, SS, and INV presented in NaCl-M2 treatment, the highest values of SPAD, FLAV, and FERARI presented in NaCl-M3 treatment, the highest activity of superoxide dismutase (SOD) presented in NaCl-M1 treatment, the highest activity of glutathione peroxidase (GSH-Px) presented in NaCl treatment, and the highest peroxisome (POD) activity presented in CK. The 14 significant physiological and biochemical indicators in the leaves of L. barbarum seedling were analyzed by grey system correlation degree method. Our results suggested that the weighted correlation degree of phy-siological and biochemical indices of L. barbarum inoculated potassium-solubilizing bacteria was higher than that under CK and NaCl treatments. The highest weighted correlation was observed in NaCl-M2 treatment. Therefore, adding KSBGY02 potassium-solubilizing bacteria could alleviate the salt stress for L. barbarum seedlings.

[New insights into vascular mechanobiology: roles of matrix mechanics in regulating smooth muscle cell function].

Vascular smooth muscle cell (vSMC) is the predominant cell type in the blood vessel wall and is constantly subjected to a complex extracellular microenvironment. Mechanical forces that are conveyed by changes in stiffness/elasticity, geometry and topology of the extracellular matrix have been indicated by experimental studies to affect the phenotype and function of vSMCs. vSMCs perceive the mechanical stimuli from matrix via specialized mechanosensors, translate these stimuli into biochemical signals controlling gene expression and activation, with the consequent modulation in controlling various aspects of SMC behaviors. Changes in vSMC behaviors may further cause disruption of vascular homeostasis and then lead to vascular remodeling. A better understanding of how SMC senses and transduces mechanical forces and how the extracellular mechano-microenvironments regulate SMC phenotype and function may contribute to the development of new therapeutics for vascular diseases.

Clinical characteristics and ABCC2 genotype in Dubin-Johnson syndrome: A case report and review of the literature.

BACKGROUND: Dubin-Johnson syndrome (DJS) is a benign autosomal recessive liver disease involving mutations of the ABCC2 gene. It is characterized by chronic or intermittent conjugated hyperbilirubinemia, with chronic idiopathic jaundice as the main clinical manifestation. Genetic alterations of the ABCC2 gene are commonly used for diagnosing DJS; however, the causative ABCC2 point mutation in Chinese patients remains unknown. Research on ABCC2 mutations in Chinese DJS patients is extremely rare, and the diagnosis of DJS remains limited. The routine analysis of ABCC2 mutations is helpful for the diagnosis of DJS. Here, we report the clinical characteristics and ABCC2 genotype of an adult female DJS patient. This article is to expound the discovery of more potentially pathogenic ABCC2 variants will that contribute to DJS identification. CASE SUMMARY: This study investigated a woman referred for DJS and involved clinical and genetic analyses. ABCC2 mutations were identified by next-generation sequencing (NGS). The patient showed intermittent jaundice and conjugated hyper-bilirubinemia. Histopathological examinations were consistent with the typical phenotype of DJS. Genetic diagnostic analysis revealed an ABCC2 genotype exhibiting a pathogenic variant, namely c.2443C>T (p.Arg815*), which has not been reported previously in the domestic or foreign literature. CONCLUSION: Pathogenic ABCC2 mutations play an important role in the diagnosis of DJS, especially in patients with atypical presentations. Currently, NGS is used in the routine analysis of DJS cases and such tests of further cases will better illuminate the relationship between various genotypes and phenotypes of DJS.

Clinical activity changes in the neurology department of Wenzhou during the COVID-19 pandemic: an observational analysis.

OBJECTIVE: To explore the activity changes in neurology clinical practice that have occurred in tertiary public hospitals during the COVID-19 pandemic. METHODS: Outpatient and inpatient data from the neurology department were extracted from the electronic medical record system of three tertiary Grade A hospitals in Wenzhou. Data were analyzed across 5 months following the beginning of the pandemic (from January 13 to May 17) and compared with the same period in 2019. Data on reperfusion therapy for acute infarction stroke were extracted monthly from January to April. RESULTS: The number of outpatients declined from 102,300 in 2019 to 75,154 in 2020 (26.54%), while the number of inpatients in the three tertiary Grade A hospitals decreased from 4641 to 3437 (25.94%). The latter trend showed a significant drop from the 3rd week to the 7th week. The number of patients in these hospitals decreased significantly, and a significant drop was seen in the neurology department. As usual, stroke was the most common disease observed; however, anxiety/depression and insomnia increased dramatically in the outpatient consultation department. CONCLUSIONS: The results of our study revealed the effects of the COVID-19 pandemic in the clinical practice of neurology in Wenzhou during the outbreak. Understanding the pandemic's trends and impact on neurological patients and health systems will allow for better preparation of neurologists in the future.

VAMP3 and SNAP23 as Potential Targets for Preventing the Disturbed Flow-Accelerated Thrombus Formation.

Disturbed blood flow has been recognized to promote platelet aggregation and thrombosis via increasing accumulation of von Willebrand factor (VWF) at the arterial post-stenotic sites. The mechanism underlying the disturbed-flow regulated endothelial VWF production remains elusive. Here we described a mouse model, in which the left external carotid artery (LECA) is ligated to generate disturbed flow in the common carotid artery. Ligation of LECA increased VWF accumulation in the plasma. Carotid arterial thrombosis was induced by ferric chloride (FeCl3) application and the time to occlusion in the ligated vessels was reduced in comparison with the unligated vessels. In vitro, endothelial cells were subjected to oscillatory shear (OS, 0.5 ± 4 dynes/cm2) or pulsatile shear (PS, 12 ± 4 dynes/cm2). OS promoted VWF secretion as well as the cell conditioned media-induced platelet aggregation by regulating the intracellular localization of vesicle-associated membrane protein 3 (VAMP3) and synaptosomal-associated protein 23 (SNAP23). Disruption of vimentin intermediate filaments abolished the OS-induced translocation of SNAP23 to the cell membrane. Knockdown of VAMP3 and SNAP23 reduced the endothelial secretion of VWF. Systemic inhibition of VAMP3 and SNAP23 by treatment of mice with rapamycin significantly ameliorated the FeCl3-induced thrombogenesis, whereas intraluminal overexpression of VAMP3 and SNAP23 aggravated it. Our findings demonstrate VAMP3 and SNAP23 as potential targets for preventing the disturbed flow-accelerated thrombus formation.

Nomograms Predict Overall Survival and Cancer-Specific Survival in Patients with Fibrosarcoma: A SEER-Based Study.

PURPOSE: Due to the rarity, it is difficult to predict the survival of patients with fibrosarcoma. This study aimed to apply a nomogram to predict survival outcomes in patients with fibrosarcoma. METHODS: A total of 2235 patients with diagnoses of fibrosarcoma were registered in the Surveillance, Epidemiology, and End Results database, of whom 663 patients were eventually enrolled. Univariate and multivariate Cox analyses were used to identify independent prognostic factors. Nomograms were constructed to predict 3-year and 5-year overall survival and cancer-specific survival of patients with fibrosarcoma. RESULTS: In univariate and multivariate analyses of OS, age, sex, race, tumor stage, pathologic grade, use of surgery, and tumor size were identified as independent prognostic factors. Age, sex, tumor stage, pathologic grade, use of surgery, and tumor size were significantly associated with CSS. These characteristics were further included to establish the nomogram for predicting 3-year and 5-year OS and CSS. For the internal validation of the nomogram predictions of OS and CSS, the C-indices were 0.784 and 0.801. CONCLUSION: We developed the nomograms that estimated 3-year and 5-year OS and CSS. These nomograms not only have good discrimination performance and calibration but also provide patients with better clinical benefits.

Hypermethylation of mitochondrial DNA in vascular smooth muscle cells impairs cell contractility.

Vascular smooth muscle cell (SMC) from arterial stenotic-occlusive diseases is featured with deficiency in mitochondrial respiration and loss of cell contractility. However, the regulatory mechanism of mitochondrial genes and mitochondrial energy metabolism in SMC remains elusive. Here, we described that DNA methyltransferase 1 (DNMT1) translocated to the mitochondria and catalyzed D-loop methylation of mitochondrial DNA in vascular SMCs in response to platelet-derived growth factor-BB (PDGF-BB). Mitochondrial-specific expression of DNMT1 repressed mitochondrial gene expression, caused functional damage, and reduced SMC contractility. Hypermethylation of mitochondrial D-loop regions were detected in the intima-media layer of mouse carotid arteries subjected to either cessation of blood flow or mechanical endothelial injury, and also in vessel specimens from patients with carotid occlusive diseases. Likewise, the ligated mouse arteries exhibited an enhanced mitochondrial binding of DNMT1, repressed mitochondrial gene expression, defects in mitochondrial respiration, and impaired contractility. The impaired contractility of a ligated vessel could be restored by ex vivo transplantation of DNMT1-deleted mitochondria. In summary, we discovered the function of DNMT1-mediated mitochondrial D-loop methylation in the regulation of mitochondrial gene transcription. Methylation of mitochondrial D-loop in vascular SMCs contributes to impaired mitochondrial function and loss of contractile phenotype in vascular occlusive disease.

Bone morphogenetic protein-7 represses hepatic stellate cell activation and liver fibrosis via regulation of TGF-ß/Smad signaling pathway.

BACKGROUND: Liver fibrosis is a refractory disease whose persistence can eventually induce cirrhosis or even liver cancer. Early liver fibrosis is reversible by intervention. As a member of the transforming growth factor-beta (TGF-ß) superfamily, bone morphogenetic protein 7 (BMP7) has anti-liver fibrosis functions. However, little is known about BMP7 expression changes and its potential regulatory mechanism as well as the relationship between BMP7 and TGF-ß during liver fibrosis. In addition, the mechanism underlying the anti-liver fibrosis function of BMP7 needs to be further explored. AIM: To investigate changes in the dynamic expression of BMP7 during liver fibrosis, interactions between BMP7 and TGF-ß1, and possible mechanisms underlying the anti-liver fibrosis function of BMP7. METHODS: Changes in BMP7 expression during liver fibrosis and the interaction between BMP7 and TGF-ß1 in mice were observed. Exogenous BMP7 was used to treat mouse primary hepatic stellate cells (HSCs) to observe its effect on activation, migration, and proliferation of HSCs and explore the possible mechanism underlying the anti-liver fibrosis function of BMP7. Mice with liver fibrosis received exogenous BMP7 intervention to observe improvement of liver fibrosis by using Masson's trichrome staining and detecting the expression of the HSC activation indicator alpha-smooth muscle actin (α-SMA) and the collagen formation associated protein type I collagen (Col I). Changes in the dynamic expression of BMP7 during liver fibrosis in the human body were further observed. RESULTS: In the process of liver fibrosis induced by carbon tetrachloride (CCl4) in mice, BMP7 protein expression first increased, followed by a decrease; there was a similar trend in the human body. This process was accompanied by a sustained increase in TGF-ß1 protein expression. In vitro experiment results showed that TGF-ß1 inhibited BMP7 expression in a time- and dose-dependent manner. In contrast, high doses of exogenous BMP7 inhibited TGF-ß1-induced activation, migration, and proliferation of HSCs; this inhibitory effect was associated with upregulation of pSmad1/5/8 and downregulation of phosphorylation of Smad3 and p38 by BMP7. In vivo experiment results showed that exogenous BMP7 improved liver fibrosis in mice. CONCLUSION: During liver fibrosis, BMP7 protein expression first increases and then decreases. This changing trend is associated with inhibition of BMP7 expression by sustained upregulation of TGF-ß1 in a time- and dose-dependent manner. Exogenous BMP7 could selectively regulate TGF-ß/Smad pathway-associated factors to inhibit activation, migration, and proliferation of HSCs and exert anti-liver fibrosis functions. Exogenous BMP7 has the potential to be used as an anti-liver fibrosis drug.

Identification and molecular characterization of a novel anti-lipopolysaccharide factor (ALF) from red swamp crayfish, Procambarus clarkii.

Anti-lipopolysaccharide factors are a group of small proteins with broad spectrum antiviral property and antibacterial activity. Herein, we obtained the genomic sequence of the Procambarus clarkii anti-lipopolysaccharide factor (PcALF) gene by using polymerase chain reaction to investigate its expression pattern in various tissues and in the immune tissues (Hepatopancreas) following exposure to pathogens. The deduced protein of PcALF was conserved; it displayed the signal peptides and putative lipo-polysaccharide binding domain, particularly the two conserved cysteine amino acid residues at both ends of the domain. The recombinant protein of PcALF was successfully expressed in Escherichia coli and rabbit anti-PcALF polyclonal antibodies were prepared. The qRT-PCR analysis showed unequal distribution of PcALF transcript in the examined tissues, however the transcript level was greatest in hepatopancreas. The challenge with peptidoglycan (PGN), lipo-polysaccharide (LPS) and Poly I:C significantly enhanced expression level of PcALF in hepatopancreas when compared with the PBS control. RNA interference of PcALF affected the mRNA expression levels of immune-related genes. Taken together, our data suggested that PcALF is an inducible protein and could play a key biological role in the innate immune defense of P. clarkii.