Search results for "ACTIVATION"

Amphiregulin activates human hepatic stellate cells and is upregulated in non alcoholic steatohepatitis

2015

AbstractAmphiregulin (AR) involvement in liver fibrogenesis and hepatic stellate cells (HSC) regulation is under study. Non-alcoholic fatty liver disease (NAFLD) and its more severe form non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular cancer (HCC). Our aim was to investigate ex vivo the effect of AR on human primary HSC (hHSC) and verify in vivo the relevance of AR in NAFLD fibrogenesis. hHSC isolated from healthy liver segments were analyzed for expression of AR and its activator, TNF-α converting enzyme (TACE). AR induction of hHSC proliferation and matrix production was estimated in the presence of antagonists. AR involvement in fibrogenesis was also ass…

Histamine and spontaneously released mast cell granules affect the cell growth of human hepatocellular carcinoma cells

2007

The role of mast cells in tumor growth is still controversial. In this study we analyzed the effects of both histamine and pre-formed mediators spontaneously released by mast cells on the growth of two human hepatocellular carcinoma cell lines, HA22T/VGH and HuH-6, with different characteristics of differentiation, biological behavior and genetic defects. We showed that total mast cell releasate, exocytosed granules (granule remnants) and histamine reduced cell viability and proliferation in HuH-6 cells. In contrast, in HA22T/VGH cells granule remnants and histamine induced a weak but significant increase in cell growth. We showed that both cell lines expressed histamine receptors H(1) and …

Effects of Norepinephrine and Cardiotrophin-1 on Phospholipase D Activity and Incorporation of Myristic Acid Into Phosphatidylcholine in Rat Heart

2004

The present study is part of a project on phospholipase D (PLD) in cardiac hypertrophy and analyzed effects on PLD activity of two growth stimuli, norepinephrine (NE) and cardiotrophin-1 (CT-1), in incubated rat heart. Phosphatidylcholine (PC) was labeled by 3H-myristic acid. PLD produced 3H-phosphatidylethanol (3H-PEth) from 3H-PC in the presence of ethanol and maintained a basal formation of 3H-PEth. Short-term and long-term exposure to NE for 2 or 13 h, respectively, enhanced the formation of 3H-PEth, which was blocked by prazosin. Long-term pretreatment with NE or CT-1 increased the incorporation of 3H-myristic acid into PC, which was blocked by atenolol. When the 3H-PEth formation was …

Dihydrocucurbitacin B, isolated from Cayaponia tayuya, reduces damage in adjuvant-induced arthritis

2005

23,24-Dihydrocucurbitacin B, from the anti-rheumatic plant Cayaponia tayuya, was tested on arthritis induced by adjuvant to corroborate the anti-inflammatory properties of this plant. Arthritis was induced in Lewis rats; the resulting arthritic rats were then treated with dihydrocucurbitacin B (1 mg/kg orally, daily, 1 week). The effect of dihydrocucurbitacin B on the synthesis, release, and activity of pro-inflammatory enzymes (elastase, cyclooxygenase-2, and nitric oxide synthase-2) as well as its effect on different mediators (tumor necrosis factor-alpha and interleukin-1beta) were determined. Dihydrocucurbitacin B modified the evolution of the clinical symptoms, reducing the swelling an…

Changes in lymphocyte subsets after cardiac surgery in children.

2001

Children undergoing cardiopulmonary bypass (CPB) operations have an increased risk of developing severe infections. Impairment of the immune system may contribute to the development of sequelae such as capillary leaks, pulmonary dysfunction and auto-immune reactions. The objective of this study was to investigate the impact of cardiac surgery with CPB on the immune system of infants and young children. We conducted a prospective study to investigate the changes in circulating lymphocyte subpopulations in a sample of 21 consecutive infants and young children undergoing cardiac surgery for congenital heart disease. The following statistically significant (P<0.05) results were obtained: leucoc…

The Dual Role of the GABAA Receptor in Peripheral Inflammation and Neuroinflammation: A Study in Hyperammonemic Rats

2021

Cognitive and motor impairment in minimal hepatic encephalopathy (MHE) are mediated by neuroinflammation, which is induced by hyperammonemia and peripheral inflammation. GABAergic neurotransmission in the cerebellum is altered in rats with chronic hyperammonemia. The mechanisms by which hyperammonemia induces neuroinflammation remain unknown. We hypothesized that GABAA receptors can modulate cerebellar neuroinflammation. The GABAA antagonist bicuculline was administrated daily (i.p.) for four weeks in control and hyperammonemic rats. Its effects on peripheral inflammation and on neuroinflammation as well as glutamate and GABA neurotransmission in the cerebellum were assessed. In hyperammone…

Effects of inhibitors of cGMP-dependent protein kinase in atrial heart and aortic smooth muscle from rats

1995

Several activators of cGMP-dependent protein kinase (protein kinase G) such as 8-Br-cGMP reduced force of contraction in rat left atria. Inhibitors of protein kinase G antagonized the negative inotropic effect of 8-Br-cGMP but not of acetylcholine in atria. However, the acetylcholine-induced relaxation in aortic rings was significantly inhibited by protein kinase G inhibition. It is concluded that the reduction by 8-Br-cGMP of force of contraction in atria is related to activation of protein kinase G. In response to acetylcholine, activation of protein kinase G is probably a major step in smooth muscle relaxation but is not involved in the reduction of force of contraction in atria.

Endothelial activation and insulin resistance: Comparison between essential hypertensives and hypertensive patients with Metabolic Syndrome

2005

Dissociation of airway responsiveness and bronchoalveolar lavage (BAL) cell composition in sensitized guinea-pigs after daily inhalation of ovalbumin

1994

Summary. The association between inflammatory cell influx, cell activation status and change of airway responsiveness to acelylcholine (ACh) after daily inhalation of ovalbumin (OA) in sensitized guinea–pigs was investigated. Starting 3 weeks after sensitization (OA at 50mg/kg s.c. + i.p.) guinea–pigs were exposed daily to 2% OA (10min: undercover of 0.5Smg/kg mepyramine i.p. 15min before OA) for 2 weeks. Concentration–response curves (CRCs) for inhaled ACh were performed 24 h after the last OA–challenge and 24 h after another single OA–inhalation 1 week later. CRCs for inhaled ACh were neither affected 24 h after the last OA challenge (daily for two weeks) nor 24 h after another OA–inhalat…

Cyclophosphamide Pulse Therapy after Natalizumab Discontinuation for Multiple Sclerosis: a multicenter study.

2015

Importance: Natalizumab discontinuation induces the recurrence of Multiple Sclerosis (MS) disease activity: Currently no therapeutic approach has been found able to abolish disease reactivation. Objective: To collect data from patients with MS switching from natalizumab to cyclophosphamide. Design: Retrospective multicentre study. Setting: Nine Multiple Sclerosis Centers in Italy. Participants: A total of 47 patients with clinically definite RR-MS switched to cyclophosphamide after natalizumab discontinuation. Two patients were excluded from the analysis because received less than 12 natalizumab infusions. The remaining 45 patients were subdivided into two main groups: Early Treatment (peri…