Platycodi Radix Extract Prevents Hepatic Steatosis by Enhancing Bile Acid Synthesis in a High-Fat Diet-Induced Fatty Liver Mouse Model.

We aimed to identify the mechanism underlying the preventive effects of non-alcoholic fatty liver disease (NAFLD) through Platycodi Radix consumption using liver proteomic and bioinformatic analysis. C57BL/6J mice were categorized into three groups: those receiving a standard chow diet (NCD), those on a high-fat diet (HFD), and those on an HFD supplemented with 5% Platycodi Radix extract (PRE). After a 12-week period, PRE-fed mice exhibited a noteworthy prevention of hepatic steatosis. Protein identification and quantification in liver samples were conducted using LC-MS/MS. The identified proteins were analyzed through Ingenuity Pathway Analysis software, revealing a decrease in proteins associated with FXR/RXR activation and a concurrent increase in cholesterol biosynthesis proteins in the PRE-treated mouse liver. Subsequent network analysis predicted enhanced bile acid synthesis from these proteins. Indeed, the quantity of bile acids, which was reduced in HFD conditions, increased in the PRE group, accompanied by an elevation in the expression of synthesis-related proteins. Our findings suggest that the beneficial effects of PRE in preventing hepatic steatosis may be mediated, at least in part, through the modulation of FXR/RXR activation, cholesterol biosynthesis, and bile acid synthesis pathways.

Heterogeneous osteoimmune profiles via single-cell transcriptomics in osteoporotic patients who fail bisphosphonate treatment.

Postmenopausal osteoporosis arises from imbalanced osteoclast and osteoblast activity, and mounting evidence suggests a role for the osteoimmune system in bone homeostasis. Bisphosphonate (BP) is an antiresorptive agent, but its treatment failure rate can be as high as 40%. Here, we performed single-cell RNA sequencing on peripheral immune cells from carefully selected postmenopausal women: non-osteoporotic, osteoporosis improved after BP treatment, and BP-failed cases. We found an increase in myeloid cells in patients with osteoporosis (specifically, T cell receptor+ macrophages). Furthermore, lymphoid lineage cells varied significantly, notably elevated natural killer cells (NKs) in the BP-failed group. Moreover, we provide fruitful lists of biomarkers within the immune cells that exhibit condition-dependent differences. The existence of osteoporotic- and BP-failure-specific cellular information flows was revealed by cell-cell interaction analysis. These findings deepen our insight of the osteoporosis pathology enhancing comprehension of the role of immune heterogeneity in postmenopausal osteoporosis and BP treatment failure.

Osteobiologies for Spinal Fusion from Biological Mechanisms to Clinical Applications: A Narrative Review.

Degenerative lumbar spinal disease (DLSD), including spondylolisthesis and spinal stenosis, is increasing due to the aging population. Along with the disease severity, lumbar interbody fusion (LIF) is a mainstay of surgical treatment through decompression, the restoration of intervertebral heights, and the stabilization of motion segments. Currently, pseudoarthrosis after LIF is an important and unsolved issue, which is closely related to osteobiologies. Of the many signaling pathways, the bone morphogenetic protein (BMP) signaling pathway contributes to osteoblast differentiation, which is generally regulated by SMAD proteins as common in the TGF-ß superfamily. BMP-2 and -4 are also inter-connected with Wnt/ß-catenin, Notch, and FGF signaling pathways. With the potent potential for osteoinduction in BMP-2 and -4, the combination of allogenous bone and recombinant human BMPs (rhBMPs) is currently an ideal fusion material, which has equalized or improved fusion rates compared to traditional materials. However, safety issues in the dosage of BMP remain, so overcoming current limitations will provide significant advancement in spine surgery. In the future, translational research and the application of clinical study will be important to overcome the current limitations of spinal surgery.

RNF2 regulates Wnt/ß-catenin signaling via TCF7L1 destabilization.

The Wnt signaling pathway is a crucial regulator of various biological processes, such as development and cancer. The downstream transcription factors in this pathway play a vital role in determining the threshold for signaling induction and the length of the response, which vary depending on the biological context. Among the four transcription factors involved in canonical Wnt/ß-catenin signaling, TCF7L1 is known to possess an inhibitory function; however, the underlying regulatory mechanism remains unclear. In this study, we identified the E3 ligase, RNF2, as a novel positive regulator of the Wnt pathway. Here, we demonstrate that RNF2 promotes the degradation of TCF7L1 through its ubiquitination upon activation of Wnt signaling. Loss-of-function studies have shown that RNF2 consistently destabilizes nuclear TCF7L1 and is required for proper Wnt target gene transcription in response to Wnt activation. Furthermore, our results revealed that RNF2 controls the threshold, persistence, and termination of Wnt signaling by regulating TCF7L1. Overall, our study sheds light on the previously unknown degradation mechanism of TCF7L1 by a specific E3 ligase, RNF2, and provides new insights into the variability in cellular responses to Wnt activation.

Transmembrane protein 150b attenuates BMP signaling in the Xenopus organizer.

The vertebrate organizer is a specified embryonic tissue that regulates dorsoventral patterning and axis formation. Although numerous cellular signaling pathways have been identified as regulators of the organizer's dynamic functions, the process remains incompletely understood, and as-yet unknown pathways remain to be explored for sophisticated mechanistic understanding of the vertebrate organizer. To identify new potential key factors of the organizer, we performed complementary DNA (cDNA) microarray screening using organizer-mimicking Xenopus laevis tissue. This analysis yielded a list of prospective organizer genes, and we determined the role of six-transmembrane domain containing transmembrane protein 150b (Tmem150b) in organizer function. Tmem150b was expressed in the organizer region and induced by Activin/Nodal signaling. In X. laevis, Tmem150b knockdown resulted in head defects and a shortened body axis. Moreover, Tmem150b negatively regulated bone morphogenetic protein (BMP) signaling, likely via physical interaction with activin receptor-like kinase 2 (ALK2). These findings demonstrated that Tmem150b functions as a novel membrane regulatory factor of BMP signaling with antagonistic effects, contributing to the understanding of regulatory molecular mechanisms of organizer axis function. Investigation of additional candidate genes identified in the cDNA microarray analysis could further delineate the genetic networks of the organizer during vertebrate embryogenesis.

Radiological Factors Associated with Bisphosphonate Treatment Failure and Their Impact on Fracture Healing in Postmenopausal Women with Osteoporotic Vertebral Fractures.

(1) Background: Bisphosphonate treatment failure is one of the most difficult clinical problems for patients with osteoporosis. This study aimed to analyze the incidence of bisphosphonate treatment failure, associated radiological factors, and effect of fracture healing in postmenopausal women with osteoporotic vertebral fractures (OVFs). (2) Methods: A total of 300 postmenopausal patients with OVFs who were prescribed bisphosphonate were retrospectively analyzed and divided into two groups according to the treatment response: response (n = 116) and non-response (n = 184) groups. The radiological factors and the morphological patterns of OVFs were included in this study. (3) Results: The initial BMD values of the spine and femur in the non-response group were significantly lower than those in the response group (all Ps < 0.001). The initial BMD value of the spine (odd ratio = 1.962) and the fracture risk assessment tool (FRAX) hip (odd ratio = 1.32) showed statistical significance in logistic regression analysis, respectively (all Ps < 0.001). (4) Conclusions: The bisphosphonate non-responder group showed a greater decrease in BMD over time than the responder group. The initial BMD value of the spine and the FRAX hip could be considered radiological factors influencing bisphosphonate non-response in the postmenopausal patients with OVFs. The failure of bisphosphonate treatment for osteoporosis has a possible negative on the fracture healing process in OVFs.

Natural Product Skatole Ameliorates Lipotoxicity-Induced Multiple Hepatic Damage under Hyperlipidemic Conditions in Hepatocytes.

Skatole (3-methylindole, 3MI) is a natural-origin compound derived from plants, insects, and microbial metabolites in human intestines. Skatole has an anti-lipid peroxidation effect and is a biomarker for several diseases. However, its effect on hepatocyte lipid metabolism and lipotoxicity has not been elucidated. Hepatic lipotoxicity is induced by excess saturated free fatty acids in hyperlipidemia, which directly damages the hepatocytes. Lipotoxicity is involved in several metabolic diseases and hepatocytes, particularly affecting nonalcoholic fatty liver disease (NAFLD) progression. NAFLD is caused by the accumulation of fat by excessive free fatty acids (FFAs) in the blood and is accompanied by hepatic damage, such as endoplasmic reticulum (ER) stress, abnormal glucose and insulin metabolism, oxidative stress, and lipoapoptosis with lipid accumulation. Hepatic lipotoxicity causes multiple hepatic damages in NAFLD and has a directly effect on the progression from NAFLD to nonalcoholic steatohepatitis (NASH). This study confirmed that the natural compound skatole improves various damages to hepatocytes caused by lipotoxicity in hyperlipidemic conditions. To induce lipotoxicity, we exposed HepG2, SNU-449, and Huh7 cells to palmitic acid, a saturated fatty acid, and confirmed the protective effect of skatole. Skatole inhibited fat accumulation in the hepatocytes, reduced ER and oxidative stress, and recovered insulin resistance and glucose uptake. Importantly, skatole reduced lipoapoptosis by regulating caspase activity. In conclusion, skatole ameliorated multiple types of hepatocyte damage induced by lipotoxicity in the presence of excess free fatty acids.

Transcriptomic Profiling Analysis of Castration-Resistant Prostate Cancer Cell Lines Treated with Chronic Intermittent Hypoxia.

Castration-resistant prostate cancer (CRPC) is still a major concern in men's health, with 375,000 cancer deaths annually. Hypoxia, which is a marked characteristic of advanced solid tumors, has been suggested to induce prostate cancer towards CRPC, metastasis and treatment resistance. To evaluate the effect of hypoxia on prostate cancer, two and five cycles of hypoxia and reoxygenation were administered using 22Rv1 cell lines and denominated as 22Rv1-CI and 22Rv1-PCI, respectively. Cancer cell migration was promoted in 22Rv1-CI compared to controls, and the expression of COL13A1 was significantly up-regulated in 22Rv1-CI according to differentially expressed gene analysis of RNA sequencing among groups. Cancer cell migration was impeded in a wound healing assay after transfecting si-COL13A1. Moreover, the expression of COL13A1 was also higher in the cell line originating from bone metastatic prostate cancer compared to other cell lines. Using the open database GEO, we also confirmed that the expression of COL13A1 was higher in bone metastatic prostate cancer tissue than in localized prostate cancer tissue in patients. Therefore, COL13A1 may be closely related to the bony metastasis of prostate cancer, and our findings may provide valuable information on the pathophysiology of the metastatic niche induced by hypoxia in patients with CRPC.

Metformin and Sildenafil Attenuate Inflammation and Suppress Apoptosis After Ischemia/Reperfusion Injuries in Rat Urinary Bladder.

PURPOSE: Although metformin and sildenafil can protect various organs against ischemia/reperfusion (I/R) injuries, their effects and mechanisms of action in bladder I/R injuries remain unknown. This study investigated the effects and mechanisms of action of metformin and sildenafil against bladder I/R insults in rats. METHODS: One hundred male Sprague-Dawley rats were randomly divided into 5 groups, each of which contained 20 rats: a sham-operated group, a bladder I/R group, and bladder I/R groups treated with metformin, sildenafil, or both agents. Ischemia was induced by clamping the bilateral common iliac arteries with atraumatic vascular clamps for 2 hours, followed by reperfusion for 7 days. During this period, rats were injected once daily with 4-mg/kg metformin and/or 1-mg/kg sildenafil. RESULTS: I/R injuries induced increased malondialdehyde levels and myeloperoxidase activity and decreased superoxide dismutase activity. These changes were attenuated by treatment with metformin and/or sildenafil. The I/R group had significantly higher Jun N-terminal kinase, p38 mitogen-activated protein kinase (MAPK), Bax, caspase-3, and nuclear factor-kappa B (NF-κB) levels, and lower extracellular signal-regulated kinase, and Bcl-2 levels in the bladder than the sham-operated group; these changes were significantly ameliorated by metformin and/or sildenafil treatment. No differences in the levels of these markers were observed between rats coadministered metformin and sildenafil and those treated with either agent alone. CONCLUSION: Metformin and sildenafil protected the rat bladder against I/R injuries. This effect may have been due to the inhibition of reactive oxygen species production through MAPK, Bax, and Bcl-2 activation, and the restoration of inflammation through NF-κB inhibition. However, the combination of metformin and sildenafil was not more effective than either agent alone.

Genome-wide RNA interference screening reveals a COPI-MAP2K3 pathway required for YAP regulation.

The transcriptional regulator YAP, which plays important roles in the development, regeneration, and tumorigenesis, is activated when released from inhibition by the Hippo kinase cascade. The regulatory mechanism of YAP in Hippo-low contexts is poorly understood. Here, we performed a genome-wide RNA interference screen to identify genes whose loss of function in a Hippo-null background affects YAP activity. We discovered that the coatomer protein complex I (COPI) is required for YAP nuclear enrichment and that COPI dependency of YAP confers an intrinsic vulnerability to COPI disruption in YAP-driven cancer cells. We identified MAP2K3 as a YAP regulator involved in inhibitory YAP phosphorylation induced by COPI subunit depletion. The endoplasmic reticulum stress response pathway activated by COPI malfunction appears to connect COPI and MAP2K3. In addition, we provide evidence that YAP inhibition by COPI disruption may contribute to transcriptional up-regulation of PTGS2 and proinflammatory cytokines. Our study offers a resource for investigating Hippo-independent YAP regulation as a therapeutic target for cancers and suggests a link between YAP and COPI-associated inflammatory diseases.

Expression of bladder α1-adrenoceptor subtype after relief of partial bladder outlet obstruction in a rat model.

Purpose: Many patients with benign prostatic hyperplasia require treatment for persistent storage symptoms, even when the obstruction is successfully relieved by surgery. Previous studies identified a characteristic increase in α1D-adrenoceptor levels in the bladder in a bladder outlet obstruction (BOO) model. Here, we investigated the expression of α1-adrenoceptor subtypes in the bladder after relief of partial BOO (pBOO) in a rat model. Materials and Methods: A total of 60 female Sprague-Dawley rats were randomly divided into three groups (sham-operated, pBOO, and pBOO relief groups), and the expression of α1-adrenoceptor subtypes in the urothelium and detrusor muscle tissues was examined by western blot. Results: The expression of the α1D-adrenoceptor was significantly higher in the urothelium and detrusor muscle tissue of the pBOO and pBOO relief groups than in the corresponding tissue of the sham-operated group. Additionally, the α1A-adrenoceptor was predominant in the sham-operated group but significantly decreased in the urothelium in the pBOO group. No significant differences were found in α1A-adrenoceptor levels in detrusor muscle or whole bladder. Conclusions: Our results showed that α1D-adrenoceptor levels were consistently increased with pBOO, even after relief, suggesting that the α1D-adrenoceptor might be a cause of persistent storage symptoms after relief of pBOO.

Fat-1 expression enhance hippocampal memory in scopolamine-induced amnesia.

Omega-3 polyunsaturated fatty acids (PUFA) are critical for optimal brain health and are involved in psychiatric and neurological ailments. Here, we report the effects of higher endogenous omega-3 PUFA on memory impairment in the hippocampus by studying mice with transgenic expression of the fat-1 gene that converts omega-6 to omega-3 PUFA. We performed Y-maze and passive avoidance tests to evaluate the memory function of fat-1 mice treated with scopolamine. Fat-1 mice showed induced alternation in the Y-maze test and increased latency in the passive avoidance test. The effects of scopolamine on hippocampal neurogenesis were confirmed by increases in the number of Ki-67- and DCX-positive cells in the fat-1 mice. Western blotting revealed increased brain-derived neurotrophic factor (BDNF) and phosphorylated cAMP response element-binding protein levels, and lower scopolamine-induced apoptosis based on the cleaved-caspase 3 protein level in fat-1 mice. These findings suggest that higher endogenous omega-3 PUFA prevented granular cell loss, increased BDNF signaling, and decreased apoptosis signaling in scopolamine-treated fat-1 mice. These processes may underlie granular cell survival and suggest potential therapeutic targets for memory impairment.

Analysis of the Extracellular Proteome of Colistin-Resistant Korean Acinetobacter baumannii Strains.

We analyzed the extracellular proteome of colistin-resistant Korean Acinetobacter baumannii (KAB) strains to identify proteome profiles that can be used to characterize extensively drug-resistant KAB strains. Four colistin-resistant KAB strains with colistin resistance associated with point mutations in pmrB and pmrC genes were analyzed. Analysis of the extracellular proteome of these strains revealed the presence of 506 induced common proteins, which were hence considered as the core extracellular proteome. Class C ADC-30 and class D OXA-23 ß-lactamases were abundantly induced in these strains. Porins (CarO and CarO-like porin), outer membrane proteins (OmpH and BamABDE), transport protein (AdeK), receptor (TonB), and several proteins of unknown function were among the specifically induced proteins. Based on the sequence homology analysis of proteins from the core proteome and those of other A. baumannii strains and pathogenic bacterial species as well as further in silico screening, we propose that CarO-like porin is an A. baumannii-specific protein and that two tryptic peptides that originate from CarO-like porin detected by tandem mass spectrometry are peptide makers of this protein.

Changes in Apoptosis-Related Proteins in The Urothelium of Rat Bladder Following Partial Bladder Outlet Obstruction and Subsequent Relief.

PURPOSE: Partial bladder outlet obstruction (PBOO) induces sustained bladder over-distension, leading to ischemia/reperfusion (I/R)-related oxidative damage of the urothelium via apoptosis. The present study aimed to investigate the sequential course of apoptosis in the urothelium of rat bladder and identify the changes in apoptosis-related proteins during PBOO and subsequent relief.  Materials and Methods: The study was conducted using 60 female Sprague-Dawley rats divided into three groups: sham-operated, PBOO only, and PBOO plus subsequent relief. PBOO was induced for 2 weeks, and then the obstruction was relieved by removal of the ligature. The urothelium was assessed by a histological analysis, and expression levels of apoptosis-related proteins were detected by quantitative PCR and immunoblotting. RESULTS: Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells were significantly increased in the PBOO only group when compared with the sham-operated group, and decreased in the PBOO relief group when compared with the PBOO group (P < 0.001). From the quantitative PCR and the western blot analyses, expression of Bax, caspase-3, P38, and Jnk was significantly increased in the PBOO group (P < 0.001). However, expression of Erk, Bcl-2 significantly decreased in the PBOO group (P < 0.001). The expression of Erk and Bcl-2 significantly increased in the PBOO relief group when compared with the PBOO group (P < 0.001). In comparison to the sham-operated group, expression levels of survivin significantly increased in both the PBOO and PBOO plus relief groups (P < 0.001). In addition, the expression levels were significantly different between the PBOO and PBOO plus relief groups (P < 0.001). CONCLUSION: PBOO induced apoptosis of urothelium is related to alterations in the MAPK signaling pathways and apoptosis-related protein change. These results may also suggest that the pro-survival Erk signaling cascade and the expression survivin are activated in response to ischemic bladder injury and associated with initiation of bladder restoration in PBOO and subsequent relief. However, the mechanism of survivin as anti-apoptotic protein in ischemic bladder injuries remains unclear.

Simple Method To Characterize the Ciliary Proteome of Multiciliated Cells.

Motile cilia of multiciliated epithelial cells have important roles in animal development and cell homeostasis. Although several studies have identified and reported proteins localized in this complex organelle and the related immotile primary cilia from various cell types, it is still challenging to isolate high quantities of ciliary proteins for proteomic analysis. In this study, African clawed frog (Xenopus laevis) embryos, which have many multiciliated cells in the epidermis, were treated with a simple ionic buffer to identify 1009 proteins conserved across vertebrates; these proteins were putatively localized in motile cilia. Using two ciliary proteome databases, we confirmed that previously validated cilia-associated proteins are highly enriched in our ciliary proteome. Proteins localized at the transition zone and Ellis-van Creveld zone, which are distinct regions at the base of cilia, near the junction with the apical cell surface, were isolated using our method. Among the newly identified ciliary proteins, we report that KRT17 may have an unrecognized function in motile cilia. Hence, the method developed in this study would be useful for understanding the ciliary proteome.

Targeting CYP4A attenuates hepatic steatosis in a novel multicellular organotypic liver model.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) begins as simple hepatic steatosis, but further progress to chronic liver diseases results in severe liver damage and hepatic failure. However, therapeutic options are scarce due to the lack of reliable human in vitro liver models for understanding disease progression mechanisms and developing therapies. RESULTS: We describe here a novel method for generating 3D hepatic spheroids using HepaRG cells, vascular endothelial cells, and mesenchymal stem cells cultured on a thick layer of soft matrix in a narrow conical tube; this method improved self-organization efficiency and functional competence. We further developed a 3D hepatic steatosis model with excess glucose and palmitate, accurately recapitulating steatosis phenotypes such as neutral lipid accumulation, enhanced expression of lipogenesis and gluconeogenesis markers, increased intracellular triglyceride content, and reduced glucose uptake. The expression and activity of cytochrome P450 4A (CYP4A), a hepatic glucose and lipid homeostasis enzyme, that is highly expressed in liver tissues from NAFLD patients, was induced in our in vitro steatosis model, and inhibiting CYP4A with the selective inhibitor HET0016 or a specific siRNA ameliorated steatosis-related pathology through reduced ER stress and improved insulin signaling. CONCLUSIONS: We provide here a novel 3D human cell-based hepatic model that can be easily generated and reliably simulate hepatic steatosis pathology. We have experimentally validated its potential for target validation and drug evaluation by focusing on CYP4A, which may serve as a translational platform for drug development.

Synergistic anticancer effect of acteoside and temozolomide-based glioblastoma chemotherapy.

Temozolomide (TMZ) is an alkylating agent commonly used as a first­line treatment for high­grade glioblastoma. However, TMZ has short half­life and frequently induces tumor resistance, which can limit its therapeutic efficiency. In the present study, it was hypothesized that combined treatment with TMZ and acteoside has synergistic effects in glioblastoma therapy. Using cell viability and wound­healing assays, it was determined that this treatment regimen reduced cell viability and migration to a greater extent than either TMZ or acteoside alone. Following previous reports that TMZ affected autophagy in glioma cells, the present study examined the effects of TMZ + acteoside combination treatment on apoptosis and autophagy. The TMZ + acteoside combination treatment increased the cleavage of caspase­3 and levels of B­cell lymphoma 2 (Bcl­2)­associated X protein and phosphorylated p53, and decreased the level of Bcl­2. The combination treatment increased microtubule­associated protein 1 light chain 3 and apoptosis­related gene expression. It was also determined that TMZ + acteoside induced apoptosis and autophagy through the mitogen­activated protein kinase signaling pathway. These findings suggest that acteoside has beneficial effects on TMZ­based glioblastoma therapy.

Antibiotic treatment modulates protein components of cytotoxic outer membrane vesicles of multidrug-resistant clinical strain, Acinetobacter baumannii DU202.

BACKGROUND: Outer membrane vesicles (OMVs) of Acinetobacter baumannii are cytotoxic and elicit a potent innate immune response. OMVs were first identified in A. baumannii DU202, an extensively drug-resistant clinical strain. Herein, we investigated protein components of A. baumannii DU202 OMVs following antibiotic treatment by proteogenomic analysis. METHODS: Purified OMVs from A. baumannii DU202 grown in different antibiotic culture conditions were screened for pathogenic and immunogenic effects, and subjected to quantitative proteomic analysis by one-dimensional electrophoresis and liquid chromatography combined with tandem mass spectrometry (1DE-LC-MS/MS). Protein components modulated by imipenem were identified and discussed. RESULTS: OMV secretion was increased > twofold following imipenem treatment, and cytotoxicity toward A549 human lung carcinoma cells was elevated. A total of 277 proteins were identified as components of OMVs by imipenem treatment, among which ß-lactamase OXA-23, various proteases, outer membrane proteins, ß-barrel assembly machine proteins, peptidyl-prolyl cis-trans isomerases and inherent prophage head subunit proteins were significantly upregulated. CONCLUSION: In vitro stress such as antibiotic treatment can modulate proteome components in A. baumannii OMVs and thereby influence pathogenicity.

Genomic characterization of extensively drug-resistant Acinetobacter baumannii strain, KAB03 belonging to ST451 from Korea.

Extensively drug-resistant (XDR) Acinetobacter baumannii strains have emerged rapidly worldwide. The antibiotic resistance characteristics of XDR A. baumannii strains show regional differences; therefore, it is necessary to analyze both genomic and proteomic characteristics of emerging XDR A. baumannii clinical strains isolated in Korea to elucidate their multidrug resistance. Here, we isolated new sequence type of XDR A. baumannii clinical strain (KAB03) from Korean hospitals and performed comprehensive genome analyses. The strain belongs to new sequence type, ST451. Single nucleotide polymorphism (SNP) analysis with other types of A. baumannii strains revealed that KAB03 has unique SNP pattern in the regions of gyrB and gpi of MLST profiles. A. baumannii KAB03 harbours three antibiotic resistance islands (AbGRI1, 2, and 3). AbGRI1 harbours two copies of Tn2006 containing blaOXA-23, which play an important role in antibiotic resistance. AbGRI2 possesses aminoglycoside resistant gene aph(3')-Ic and class A ß-lactamase blaTEM. AbGIR3 has macrolide resistant genes and aminoglycoside resistant gene armA. A. baumannii KAB03 harbours mutations in pmrB and pmrC, which are believed to confer colistin resistance. In addition, proteomic and transcriptional analysis of KAB03 confirmed that ß-lactamases (ADC-73 and OXA-23), Ade efflux pumps (AdeIJK), outer membrane proteins (OmpA and OmpW), and colistin resistance genes (PmrCAB) were major proteins responsible for antibiotic resistance. Our proteogenomic results provide valuable information for multi-drug resistance in emerging XDR A. baumannii strains belonging to ST451.

Clinical proteomic analysis of scrub typhus infection.

BACKGROUND: Scrub typhus is an acute and febrile infectious disease caused by the Gram-negative α-proteobacterium Orientia tsutsugamushi from the family Rickettsiaceae that is widely distributed in Northern, Southern and Eastern Asia. In the present study, we analysed the serum proteome of scrub typhus patients to investigate specific clinical protein patterns in an attempt to explain pathophysiology and discover potential biomarkers of infection. METHODS: Serum samples were collected from three patients (before and after treatment with antibiotics) and three healthy subjects. One-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis followed by liquid chromatography-tandem mass spectrometry was performed to identify differentially abundant proteins using quantitative proteomic approaches. Bioinformatic analysis was then performed using Ingenuity Pathway Analysis. RESULTS: Proteomic analysis identified 236 serum proteins, of which 32 were differentially expressed in normal subjects, naive scrub typhus patients and patients treated with antibiotics. Comparative bioinformatic analysis of the identified proteins revealed up-regulation of proteins involved in immune responses, especially complement system, following infection with O. tsutsugamushi, and normal expression was largely rescued by antibiotic treatment. CONCLUSIONS: This is the first proteomic study of clinical serum samples from scrub typhus patients. Proteomic analysis identified changes in protein expression upon infection with O. tsutsugamushi and following antibiotic treatment. Our results provide valuable information for further investigation of scrub typhus therapy and diagnosis.