Monoclonal enolase-1 blocking antibody ameliorates pulmonary inflammation and fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic fatal disease with limited therapeutic options. The infiltration of monocytes and fibroblasts into the injured lungs is implicated in IPF. Enolase-1 (ENO1) is a cytosolic glycolytic enzyme which could translocate onto the cell surface and act as a plasminogen receptor to facilitate cell migration via plasmin activation. Our proprietary ENO1 antibody, HL217, was screened for its specific binding to ENO1 and significant inhibition of cell migration and plasmin activation (patent: US9382331B2). METHODS: In this study, effects of HL217 were evaluated in vivo and in vitro for treating lung fibrosis. RESULTS: Elevated ENO1 expression was found in fibrotic lungs in human and in bleomycin-treated mice. In the mouse model, HL217 reduced bleomycin-induced lung fibrosis, inflammation, body weight loss, lung weight gain, TGF-ß upregulation in bronchial alveolar lavage fluid (BALF), and collagen deposition in lung. Moreover, HL217 reduced the migration of peripheral blood mononuclear cells (PBMC) and the recruitment of myeloid cells into the lungs. In vitro, HL217 significantly reduced cell-associated plasmin activation and cytokines secretion from primary human PBMC and endothelial cells. In primary human lung fibroblasts, HL217 also reduced cell migration and collagen secretion. CONCLUSIONS: These findings suggest multi-faceted roles of cell surface ENO1 and a potential therapeutic approach for pulmonary fibrosis.

Berberine regulates the protein expression of multiple tumorigenesis-related genes in hepatocellular carcinoma cell lines.

BACKGROUND: Hepatocellular carcinoma (HCC) is the seventh most common malignancy and the third leading cause of cancer-related death worldwide with an extremely grim prognosis. Berberine (BBR) has been found to inhibit proliferation of human HCC cells, although the underlying mechanism(s) are unclear. METHODS: Protein expression was detected by Western blots. Cell viability was determined by using the CellTiter Assay kit. RESULTS: We confirm that BBR treatment inhibits HepG2, Hep3B, and SNU-182 cell viability, and suggest that it regulates this proliferation via the modulation of multiple tumorigenesis-related genes protein expression. BBR treatment up-regulated protein expression of tumor suppressor genes, including Kruppel-like factor 6 (KLF6), activating transcription factor 3 (ATF3) and p21, while down-regulating the expression of selected oncogenes, including E2F transcription factor 1 (E2F1) and pituitary tumor transforming gene 1 (PTTG1). The specific extracellular signal-regulated kinases 1/2 (ERK1/2) inhibitor, PD98059, partially inhibited BBR effects including reduction of cell viability, and up-regulation of KLF6 and ATF3 expressions; although, PD98059 did not alter the down-regulation of E2F1 and PTTG1 expression by BBR. CONCLUSIONS: Our results suggest that BBR inhibits HCC cell viability by modulating multiple tumorigenesis-related genes, and that up-regulation of tumor suppressor genes by BBR is in part the result of ERK1/2 action. The results of this study augment our understanding of the mechanisms underlying the effect of BBR on hepatocellular cancers and provide further evidence as to the biological plausibility of this agent's role in the treatment of these malignancies.

Potential effect of resistin on the ET-1-increased reactions of blood pressure in rats and Ca2+ signaling in vascular smooth muscle cells.

Resistin and endothelin-1 (ET-1) are upregulated in people with type II diabetes mellitus, central obesity, and hypertension. ET-1 signaling is involved in Ca(2+)-contraction coupling and related to blood pressure regulation. The aim of this study is to investigate the role of resistin on ET-1-increased blood pressure and Ca(2+) signaling. The blood pressure and cytosolic Ca(2+) of vascular smooth muscle cells (VSMCs) of Sprague-Dawley rats were detected. The data demonstrated that resistin accelerated and prolonged ET-1-induced increases in blood pressure and had significant effects on ET-1-increased Ca(2+) reactions. Resistin-enhanced ET-1-increased Ca(2+) reactions were reversed by blockers of store-operated Ca(2+) entry (SOCE) and extracellular-signal-regulated kinase (ERK). The endogenous expression of Orai and stromal interaction molecular (STIM) were characterized in the VSMCs. Furthermore, resistin-enhanced ET-1 Ca(2+) reactions and the resistin-dependent activation of SOCE were abolished under STIM1-siRNA treatment, indicating that STIM1 plays an important role in resistin-enhanced ET-1 Ca(2+) reactions in VSMCs. Resistin appears to exert effects on ET-1-induced Ca(2+) increases by enhancing the activity of ERK-dependent SOCE (STIM1-partcipated), and may accelerate and prolong ET-1-increased blood pressure via the same pathway.

Excessive Expression of Microglia/Macrophage and Proinflammatory Mediators in Olfactory Bulb and Olfactory Dysfunction After Stroke.

BACKGROUND/AIM: Olfactory dysfunction can be caused by stroke but the pathogenesis is still unclear. Previous studies have proved that olfactory dysfunction could be caused by microglia activation in the olfactory bulb and that middle cerebral artery occlusion (MCAO) may induce ipsilateral olfactory bulb microglia activation. This study aimed to explore the possible pathogenesis of ischemic stroke-induced olfactory dysfunction. MATERIALS AND METHODS: We used a rat model of MCAO to simulate ischemic stroke. Olfactory function tests were performed using buried food test. The mRNA expression of olfactory marker protein (OMP), microglia/macrophage activation, and proinflammatory mediators were measured using reverse transcription-quantitative polymerase chain reaction. RESULTS: Following MCAO, rats had poorer olfactory performance. In the olfactory bulb of the rats, the mRNA expression of OMP decreased and the mRNA expression of microglia/macrophage activation and proinflammatory mediators increased. CONCLUSION: Ischemic stroke causes microglia/macrophage activation and promotes neuroinflammation in the olfactory bulb, causing olfactory dysfunction.

Soluble epoxide hydrolase inhibition enhances anti-inflammatory and antioxidative processes, modulates microglia polarization, and promotes recovery after ischemic stroke.

BACKGROUND: Ischemic stroke triggers inflammatory responses and oxidative stress in the brain, and microglia polarization affects the degree of neuroinflammation. It has been reported that the inhibition of soluble epoxide hydrolase (sEH) activity protects brain tissue. However, the anti-inflammatory and antioxidative effects of sEH inhibition in the ischemic brain are not fully understood. This study aimed to investigate the effects of a selective sEH inhibitor, 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA), after ischemic stroke. METHODS: Adult male rats with middle cerebral artery occlusion (MCAO) were administered with AUDA or a vehicle. Behavioral outcome, infarct volume, microglia polarization, and gene expression were assessed. RESULTS: Rats treated with AUDA showed better behavioral outcomes and smaller infarct volumes after MCAO. After AUDA treatment, a reduction of M1 microglia and an increase of M2 microglia occurred at the ischemic cortex of rats. Additionally, there was an increase in the mRNA expressions of antioxidant enzymes and anti-inflammatory interleukin-10, and pro-inflammatory mediators were decreased after AUDA administration. Heme oxygenase-1 was mainly expressed by neurons, and AUDA was found to improve the survival of neurons. CONCLUSION: The results of this study provided novel and significant insights into how AUDA can improve outcomes and modulate inflammation and oxidative stress after ischemic stroke.

Development of a Modified Surgical Technique for Simulating Ischemic Cerebral Cortex Injury in Rats.

BACKGROUND/AIM: Middle cerebral artery occlusion (MCAO) in rodents is an essential animal model for research focusing on ischemic stroke. To date, several kinds of surgical methods for MCAO have been developed and the craniotomy method has the advantage of direct visualization of the middle cerebral artery (MCA). MCAO at a more proximal site produces better surgical results, but it is a more invasive technique. The aim of this study was to evolve the surgical technique for simulating ischemic cerebral cortex injury in rats. MATERIALS AND METHODS: To approach proximal MCA with a less invasive procedure, a modified surgical technique for MCAO in rats was developed. Besides, rats receiving the modified and conventional method were compared with regard to infarct volume and by behavioral tests. RESULTS: Following craniotomy, we proposed that the inferior edge of the craniotomy should be enlarged with fine forceps. This modified surgical method induces larger infarct volume, significant behavioral impairment and can induce ischemic stroke. Additionally, it does not significantly increase the operation time, and has produced no obvious complications. CONCLUSION: This modified surgical technique may serve as a practical method for performing MCAO.

Inhibition of soluble epoxide hydrolase regulates monocyte/macrophage polarization and improves neurological outcome in a rat model of ischemic stroke.

It is generally understood that continuing neuroinflammation after ischemic stroke can exacerbate the brain damage. During the inflammatory hematogenous recruitment process, the monocytes and macrophages are activated into proinflammatory M1 and anti-inflammatory M2 cell types. Inhibition of soluble epoxide hydrolase (sEH) activity has been reported to regulate monocytes/macrophages, and attenuates neuroinflammation. This study aimed to evaluate whether a selective sEH inhibitor, 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA), can regulate monocyte/macrophage polarization and improve motor function in the rats with ischemic stroke induced by middle cerebral artery occlusion. We measured the infarct volume with 2,3,5-triphenyltetrazolium chloride staining and used the rotarod test to assess motor performance in rats. The monocyte/macrophage activation and mRNA expression of proinflammatory mediators were measured by flow cytometry and reverse-transcription quantitative PCR, respectively. Our results showed better neurological function and less infarct volume in the rats treated with AUDA. Compared with the vehicle group, the AUDA-treated group showed a reduction in M1 monocyte/macrophage activation and proinflammatory mRNA expressions in the infarct cortex of rats. Our data suggest that the sEH inhibition may regulate monocyte/macrophage polarization and improve neurological outcome after ischemic stroke.

Endothelin-1 regulates adiponectin gene expression and secretion in 3T3-L1 adipocytes via distinct signaling pathways.

Adiponectin, which is specifically and highly expressed in adipose tissue, has pleiotropic insulin-sensitizing effects. Endothelin-1 (ET-1) is a potent vasoconstrictive peptide mainly produced by endothelial cells. We previously showed that ET-1 can induce insulin resistance in vitro and in vivo and proposed that it might regulate adiponectin expression and secretion, thus affecting the homeostasis of whole-body energy metabolism. In the present study, we explored the regulatory effects of ET-1 on adiponectin expression and secretion and the underlying mechanisms in 3T3-L1 adipocytes using Northern blotting and ELISA. ET-1 was found to cause a significant time- and dose-dependent decrease in adiponectin expression, and this effect was inhibited by the ET type A receptor (ETAR) antagonist BQ-610 but not by the ETBR antagonist BQ-788. To explore the underlying mechanism, we examined the involvement of the cAMP-dependent protein kinase A-, phospholipase A2-, protein kinase C-, and MAPK-mediated pathways using inhibitors and found that only PD98059 and U0126, inhibitors that blocked MAPK/ERK kinase's ability to activate the ERKs, prevented ET-1-induced down-regulation of adiponectin. Furthermore, acute ET-1 treatment significantly stimulated adiponectin secretion by 3T3-L1 adipocytes, and this effect was inhibited by the ETAR antagonist BQ-610, the inositol-1,4,5-triphosphate receptor blocker 2-APB, and phospholipase C inhibitor U73122, showing that the release of adiponectin stimulated by ET-1 was mediated through the ETAR and the inositol-1,4,5-triphosphate pathway. In conclusion, ET-1 regulates adiponectin expression and secretion by two different signaling pathways in 3T3-L1 adipocytes. These findings suggested that the cardiovascular system affects adipocyte physiology by regulating the expression of adipocytokines and, consequently, energy homeostasis via vasoactive factors, such as ET-1.

Berberine Inhibits Uterine Leiomyoma Cell Proliferation via Downregulation of Cyclooxygenase 2 and Pituitary Tumor-Transforming Gene 1.

We previously demonstrated that berberine (BBR) inhibits cell proliferation and induces apoptosis in a human uterine leiomyoma (UtLM) cell line but does not demonstrate a significant cytotoxic effect in a normal human uterine smooth muscle (UtSM) cell line. However, the mechanisms of this inhibition are unclear. Of note, cyclooxygenase 2 (COX2) and pituitary tumor-transforming gene 1 (PTTG1) are overexpressed in human uterine leiomyomata and are involved in the pathogenesis of uterine fibroids (UFs). We found that COX2 and PTTG1 were overexpressed in UtLM and that BBR decreased COX2 and PTTG1 expression in UtLM cells. Our data support that UtLM and UtSM are immortalized cell lines without phenotypic alterations from parental cell types and suggest that COX2 and PTTG1 are molecular targets for BBR. However, studies in these cell lines may not reveal all activities of BBR in vivo, and we therefore proceeded to test in this report the antitumor effects of BBR in an UF nude mouse xenograft model. When UF nude mice were killed at 7 weeks, tumor weight in controls was 45 ± 7 mg versus 20 ± 3 mg ( P < .05) in the low-dose (5 mg/kg) and 7 ± 3 mg ( P < .01) in the high-dose (10 mg/kg) BBR groups, respectively. Expression of proliferation markers, cell cycle-related genes, and UF-related genes was downregulated in tumors. No unusual behavioral changes and no signs of kidney or liver damage were observed in the animals with BBR treatment. In conclusion, our data suggests that (a) COX2 and PTTG1 are molecular targets for BBR and (b) BBR is potentially an effective and safe anti-UF agent.

MicroRNA-223 Expression is Upregulated in Insulin Resistant Human Adipose Tissue.

MicroRNAs (miRNAs) are short noncoding RNAs involved in posttranscriptional regulation of gene expression and influence many cellular functions including glucose and lipid metabolism. We previously reported that adipose tissue (AT) from women with polycystic ovary syndrome (PCOS) or controls with insulin resistance (IR) revealed a differentially expressed microRNA (miRNA) profile, including upregulated miR-93 in PCOS patients and in non-PCOS women with IR. Overexpressed miR-93 directly inhibited glucose transporter isoform 4 (GLUT4) expression, thereby influencing glucose metabolism. We have now studied the role of miR-223, which is also abnormally expressed in the AT of IR subjects. Our data indicates that miR-223 is significantly overexpressed in the AT of IR women, regardless of whether they had PCOS or not. miR-223 expression in AT was positively correlated with HOMA-IR. Unlike what is reported in cardiomyocytes, overexpression of miR-223 in human differentiated adipocytes was associated with a reduction in GLUT4 protein content and insulin-stimulated glucose uptake. In addition, our data suggests miR-223 regulates GLUT4 expression by direct binding to its 3' untranslated region (3'UTR). In conclusion, in AT miR-223 is an IR-related miRNA that may serve as a potential therapeutic target for the treatment of IR-related disorders.

Berberine inhibits the proliferation of human uterine leiomyoma cells.

OBJECTIVE: To determine whether berberine (BBR), a naturally occurring plant-derived alkaloid, inhibits the proliferation of human uterine leiomyoma (UtLM) cells. DESIGN: Laboratory research. SETTING: Laboratory. PATIENT(S): UtLM and normal human uterine smooth muscle (UtSMC) cell lines. INTERVENTION(S): Treatment with [1] BBR (10, 20, and 50 µM), [2] BBR (20 and 50 µM) and/or 17ß-estradiol (E2; 10 and 100 nM), and [3] BBR (20 and 50 µM) and/or progesterone (P4; 10 and 100 nM) for 24 or 72 hours. MAIN OUTCOME MEASURE(S): Cell proliferation, cell cycle, apoptosis, and related genes expression were determined. RESULT(S): BBR inhibited UtLM cell proliferation by inducing G2/M cell cycle arrest and apoptosis. Cell cycle G2/M phase-related genes were altered by BBR treatment: the expression of cyclin A1, cyclin B1, and Cdk1 were down-regulated, while Cdk4, p21, and p53 were up-regulated. BBR-treated cells stained positively for annexin V and manifested increased BAX expression. E2- and P4-induced UtLM cell proliferation was blocked by BBR treatment. In marked contrast, even the highest concentration of BBR (50 µM) did not influence cell proliferation in UtSMC cells. CONCLUSION(S): BBR selectively inhibits cellular proliferation and blocks E2- and P4-induced cell proliferation in UtLM but not in normal UtSMC cells. In addition, BBR did not demonstrate cytotoxicity effects in normal human UtSMCs. Our results suggest BBR could be a potential therapeutic agent for the treatment of uterine leiomyoma.

The expression of the miR-25/93/106b family of micro-RNAs in the adipose tissue of women with polycystic ovary syndrome.

CONTEXT: In adipose tissue (AT) micro-RNA-93 (miR-93) is significantly overexpressed in polycystic ovary syndrome (PCOS) women and non-PCOS women with insulin resistance (IR). Overexpressed miR-93 directly inhibits glucose transporter isoform 4, impairing both glucose metabolism and insulin sensitivity. The mechanisms behind increased miR-93 expression are unclear. OBJECTIVE: Our objective was to determine whether miR-93 expression is concordant with its host gene, MCM7, which contains the miR-25/93/106b gene cluster. PATIENTS: AT was excised from 16 women with PCOS (eight with and eight without IR) and 15 non-PCOS (nine with and six without IR). MAIN OUTCOME MEASURES: Expression of MCM7 and miR-25/93/106b was measured in AT and 3T3-L1 cells. RESULTS: MCM7 expression was lower in both non-PCOS/IR and PCOS women and tended to be lowest in women with PCOS and IR. Overall, the expression of MCM7 in human AT was negatively associated with miR-93 expression and with increased subject IR. Additionally, miR-25 and miR-106b expression is uncoupled from the MCM7 host gene and are positively correlated with IR, although no PCOS-specific difference was observed. MCM7 expression appears to be negatively correlated with increasing fasting glucose. In 3T3-L1 adipocytes, increasing glucose had no effect on miR-93 or miR-25, although it reduced MCM7 and increased miR-106b expression in a dose-dependent fashion. In turn, in 3T3-L1 adipocytes, increasing insulin had no effect on either MCM7 or miR-25/93/106b expression. CONCLUSIONS: Our data suggest that the expression of MCM7 and miR-93/25 is PCOS and IR related, whereas that of miR-106b is related to IR only. In 3T3-L1 adipocytes, neither hyperglycemia nor hyperinsulinemia altered the expression of miR-93 or miR-25, although increasing glucose levels down-regulated MCM7 and paradoxically increased that of miR-106b expression. The expression of the miR-25/93/106b family may be regulated through mechanisms distinct from its host gene, MCM7. Finally, our studies suggest potential epigenetic mechanisms for both IR and PCOS.

Leptin increases endothelin type A receptor levels in vascular smooth muscle cells.

Leptin, one of the adipocyte-secreted peptides, is involved in the control of appetite and body weight. Several studies have demonstrated that plasma leptin levels are elevated in obese subjects and are positively correlated with body weight. The arterial endothelin (ET) system plays an important role in the regulation of vascular tone, and ET-1 overexpression may be involved in the pathogenesis of the hypertension associated with insulin resistance. This study was performed to explore the regulatory effects of leptin on ET receptor expression and ET binding in A10 vascular smooth muscle cells (VSMCs) by use of Northern blotting, immunoblotting, and a (125)I-labeled ET-1 binding assay. The effect of leptin on ET receptor-mediated cell proliferation was also tested. The results showed that leptin caused a significant increase in [(125)I]-ET-1 binding, which was time- and dose-dependent. Immunoblotting showed that expression of the ET type A receptor (ET(A)R) in leptin (10(-7) M)-treated cells was increased by up to 2.3-fold compared with controls. Levels of ET(A)R mRNA measured by Northern blotting were also increased by up to 2.2-fold in leptin (10(-7) M)-treated cells. Pretreatment with an ERK inhibitor, PD-98059 (2.5 x 10(-5) M), blocked the leptin-induced increase in (125)I-ET-1 binding. Finally, ET-1 (10(-7) M)-stimulated cell proliferation was enhanced by leptin (10(-7) M) pretreatment, with a maximal increase of twofold compared with controls. In conclusion, leptin increases ET(A)R expression in VSMCs in a time- and dose-dependent manner. This effect is ERK dependent and is associated with increased ET-1-stimulated cell proliferation. These findings provide support for roles for leptin and the ET system in the pathogenesis of obesity-associated hypertension.