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Understanding the underlying molecular mechanisms of liver fibrosis is important to develop effective therapy. Herein, we show that focal-adhesion-kinse (FAK) plays a key role in promoting hepatic stellate cells (HSCs) activation in vitro and liver fibrosis progression in vivo. FAK activation is associated with increased expression of α-smooth muscle actin (α-SMA) and collagen in fibrotic live tissues. Transforming growth factor beta-1 (TGF-β1) induces FAK activation in a time and dose dependent manner. FAK activation precedes the α-SMA expression in HSCs. Inhibition of FAK activation blocks the α-SMA and collagen expression, and inhibits the formation of stress fibers in TGF-β1 treated HSCs. Furthermore, inhibition of FAK activation significantly reduces HSC migration and small GTPase activation, and induces apoptotic signaling in TGF-β1 treated HSCs. Importantly, FAK inhibitor attenuates liver fibrosis in vivo and significantly reduces collagen and α-SMA expression in an animal model of liver fibrosis. These data demonstrate that FAK plays an essential role in HSC activation and liver fibrosis progression, and FAK signaling pathway could be a potential target for liver fibrosis.

Background: Streptococcus pneumoniae is a leading pathogen worldwide and its pathogenesis remains unclear. Objectives: The study aimed to investigate the secretion of interleukin-8 (IL-8) and soluble intercellular adhesion molecule-1 (ICAM-1) from A549 pneumocytes stimulated by different S. pneumoniae strains and the mechanism of blood-derived S. pneumoniae (bd-SP) in invading the blood system. Methods: Twenty-three clinical strains of S. pneumoniae isolated in 2009 along with ATCC49619 were cultured and suspended in 2018. Then, A549 pneumocytes were resuspended after culture and collection, and inoculated into culture plates. Streptococcus pneumoniae suspensions were then inoculated. Normal saline was blank control. The plates were incubated for four and eight hours. Then, the suspensions were collected and centrifuged. The supernatant was analyzed for IL-8 and ICAM-1 by ELISA. Results: The concentrations of IL-8 were 180.6, 188.5, 223.4 ± 19.9, and 230.3 ± 38.6 pg/mL for blank control, ATCC49619, blood-derived S. pneumoniae (bd-SP) and sputum-derived S. pneumoniae (sd-SP) at four-hour stimulation, respectively, and 249.2, 275.7, 224.0 ± 27.8, and 242.3 ± 33.1 pg/mL at eight-hour stimulation. The concentrations of ICAM-1 were 14.8, 12.1, 19.9 ± 17.2, and 26.1 ± 28.6 ng/mL for blank control, ATCC49619, bd-SP, and sd-SP at 4 hours, respectively, and 32.6, 150.8, 69.4 ± 45.1, and 58.7 ± 30.1 ng/mL at 8 hours. Conclusions: Streptococcus pneumoniae could upregulate the secretion of IL-8 and ICAM-1 from A549 pneumocytes. No significant difference was found between bd-SP and sd-SP which was in contrast to what was found between clinical S. pneumoniae and ATCC49619. Host response may not be a vital factor for different S. pneumoniae infections.

BACKGROUND Streptococcus pneumoniae (SP) is a Gram-positive, alpha-hemolytic, facultative anaerobic member of the genus Streptococcus. The erythromycin-resistant methylase (erm) gene and macrolide efflux (mef) gene are the 2 main genes that can mediate SP. Transposon (Tn) also plays an important role in the collection and metastasis of the gene. In the present study we investigated the drug resistance characteristics and the macrolide-resistant mechanisms of SP in Wenzhou City, China. MATERIAL AND METHODS Sixty-eight strains of SP were isolated from sputum samples of hospitalized children in the Second Affiliated Hospital of Wenzhou Medical University. These strains were analyzed using antimicrobial susceptibility tests to determine their drug resistance to 10 kinds of antibacterials. Macrolide-resistant phenotypes were identified using K-B method. PCR method was used to analyze the erm B gene, mef A gene, and int Tn gene. RESULTS Drug resistance rates of 68 strains of SP were 98.5%, 100.0%, 63.2%, 52.9%, 94.1%, 89.7%, 0.0%, 0.0%, 16.2%, and 14.7% for clindamycin, erythromycin, penicillin G, cefotaxime, tetracycline, sulfamethoxazole/trimethoprim, levofloxacin, vancomycin, chloramphenicol, and amoxicillin, respectively. Total detection rates of the erm B gene, mef A gene, and int Tn gene were 98.5%, 91.2%, and 100.0%, respectively. CONCLUSIONS SP shows significant multi-drug resistance in Wenzhou City, whereas there is no clinical value of macrolides antibiotics for SP. cMLSB mediated by erm B gene is the most predominant phenotype among macrolide-resistant SP. The int Tn gene may play an important role in horizontal transfer and clonal dissemination of SP drug resistance genes in Wenzhou City.

Objective: This study aims to observe changes in the expression of the hepatic endoplasmic reticulum stress PERK-eIF2α-ATF4 signaling pathway protein in the progression of CCl(4)-induced hepatic fibrosis in rats. Methods: Male Wistar rats were sacrificed at the end of the 2(nd), 4(th), 8(th) and 12(th) weeks, respectively. A specific test was performed to compare the pathological changes of hepatic tissues in the model and normal groups. Immunohistochemical staining and Western blot were carried out to detect the expression of p-PERK, p-eIF2α and ATF4 proteins in the hepatic tissue group. Furthermore, real-time PCR was used to detect changes in the expression of ATF4 mRNA in hepatic tissues. Results: In the eight-week and twelve-week hepatic fibrosis group, significant fibrosis hyperplasia was identified in the livers of rats, and pseudo-lobules were also formed in the livers of rats in the twelve-week hepatic fibrosis group. Immunohistochemical staining and Western blot results indicated that the expression levels of p-PERK, p-eIF2α and the ATF4 protein in the livers of rats were significantly increased from the 8(th) week compared with the normal group (P

Background As the second leading cause of cancer morbidity and death in women, cervical cancer remains an important public health problem worldwide. Novel biomarkers with high sensitivity and specificity for the early detection and diagnosis of cervical cancer are urgently needed. Increasing evidence shows that long noncoding RNAs (lncRNAs) are differentially expressed in cancer tissues and may serve as diagnostic markers. In multiple tumor types, exosomes harboring lncRNAs are actively released from tumor cells. In this study, we investigate the potential association of exosomal lncRNA expression with cervical cancer. Methods Cervicovaginal lavage specimens were collected from patients with cervical cancer and cancer-free volunteers who are HPV-positive or HPV-negative. Exosomes in these specimens were isolated by ultracentrifugation and confirmed by transmission electron microscopy. The exosomal lncRNAs HOTAIR, MALAT1, and MEG3 were quantified by qRT-PCR. Results Expression of HOTAIR, MALAT1 and MEG3 was predominantly observed in cervical cancer-derived exosomes in cervicovaginal lavage samples. The expression levels of lncRNAs were significantly different in exosomes isolated from cervical cancer patients compared to normal controls. Conclusions Our data suggest that lncRNAs in exosomes isolated from cervicovaginal lavage are differentially expressed in cervical cancer patients and cancer-free volunteers. Exosomal lncRNAs may have great potential to be used for the early detection and diagnosis of cervical cancer, and serve as convenient and noninvasive biomarkers.

Rationale Tumor necrosis factor-alpha (TNF-α) is a potent pro-inflammatory mediator and its expression is up-regulated in chronic obstructive pulmonary disease (COPD). Tristetraprolin (TTP) is implicated in regulation of TNF-α expression; however, whether TTP is involved in cigarette smoke-induced TNF-α expression has not been determined. Methods TTP expression was examined by western blot analysis in murine alveolar macrophages and alveolar epithelial cells challenged without or with cigarette smoke extract (CSE). TNF-α mRNA stability, and the decay of TNF-α mRNA, were determined by real-time quantitative RT-PCR. TNF-α protein levels were examined at the same time in these cells. To identify the molecular mechanism involved, a construct expressing the human beta-globin reporter mRNA containing the TNF-α 3’-untranslated region was generated to characterize the TTP targeted site within TNF-α mRNA. Results CSE induced TTP down-regulation in alveolar macrophages and alveolar epithelial cells. Reduced TTP expression resulted in significantly increased TNF-α mRNA stability. Importantly, increased TNF-α mRNA stability due to impaired TTP function resulted in significantly increased TNF-α levels in these cells. Forced TTP expression abrogated the increased TNF-α mRNA stability and expression induced by CSE. By using the globin reporter construct containing TNF-α mRNA 3’-untranslated region, the data indicate that TTP directly targets the adenine- and uridine-rich region (ARE) of TNF-α mRNA and negatively regulates TNF-α expression at the post-transcriptional level. Conclusion The data demonstrate that cigarette smoke exposure reduces TTP expression and impairs TTP function, resulting in significantly increased TNF-α mRNA stability and excessive TNF-α expression in alveolar macrophages and epithelial cells. The data suggest that TTP is a novel post-transcriptional regulator and limits excessive TNF-α expression and inflammatory response induced by cigarette smoke.