Adenosine triphosphate affects interleukin -1beta release by T98G glioblastoma cells through a purinoceptor-independent mechanism.

T98G glioblastoma cells were previously shown to significantly increase interleukin-1beta (IL-1beta) mRNA levels in response to IL-1beta stimulation. This work demonstrates that in such conditions T98G, despite possessing biologically active interleukin converting enzyme, do not release detectable amounts of IL-1beta, even in the presence of 20 mM adenosine triphosphate (ATP). IL-1beta secretion is observed only following concomitant stimulation with 1000 units/ml of IL-1beta and 20 mM ATP. ATP induces a dose-dependent depolarization of T98G plasma membrane, whereas it does not affect Ca(2+) concentration or cell membrane permeability. Our data, together with the observation that the depolarizing effects of ATP are retained after preincubation with 100 microM suramin, an antagonist of P2-purinoceptors, suggest that ATP plays a role in IL-1beta secretion by T98G but its effects do not occur through P2-purinoceptors.

Selective induction of MCP-1 in human mesangial cells by the IL-6/sIL-6R complex.

Interleukin (IL) 6, an autocrine growth factor for mesangial cells, and chemokines, which are released from activated mesangial cells and induce leukocyte infiltration, play a critical role in the progression of immune system mediated renal diseases. Since the reciprocal relationship between IL-6 and chemokines in renal inflammation has been barely investigated, we have analyzed whether IL-6 (500 ng/ml), alone or in combination with the soluble form of its receptor (sIL-6R, 200 ng/ml), can induce normal human mesangial cells (NHMC) to release alpha and/or beta chemokines: MCP-1 (monocyte chemoattractant protein 1), IL-8, Rantes (regulated on activation, normal T cell expressed and secreted), and MIP-1alpha (macrophage inflammatory protein 1alpha). Whereas IL-6 or sIL-6R alone were ineffective in inducing significant chemokine release from NHMC, the simultaneous treatment with IL-6 and sIL-6R showed a significant interaction, leading to a strong synergic effect on MCP-1 synthesis and release without exerting any relevant activity on IL-8, Rantes, or MIP-1alpha. Consistently with the unresponsiveness to IL-6, mRNA and protein expression analysis of the two subunits which form the functional IL-6 receptor showed that NHMC express only the gp130 signal-transducing chain and not the subunit-specific IL-6R (gp80). These findings support an unexpected role of the IL-6 system in kidney inflammatory reactions through the selective regulation of monocyte recruitment.

Inflammatory molecule release by beta-amyloid-treated T98G astrocytoma cells: role of prostaglandins and modulation by paracetamol.

Deposition of beta-amyloid in the brain triggers an inflammatory response which accompanies the neuropathologic events of Alzheimer's disease and contributes to the destruction of brain tissue. The present study shows that beta-amyloid can stimulate human astrocytoma cells (T98G) to secrete the proinflammatory factors interleukin-6 and prostaglandins. Furthermore, prostaglandins can stimulate T98G to secrete interleukin-6, which in turn triggers the formation of additional prostaglandins. Prostaglandins are, therefore, a key element in the induction and maintenance of a state of chronic inflammation in the brain which may exacerbate the fundamental pathology in Alzheimer patients. Paracetamol (0.01-1000 microM), an unusual analgesic/antipyretic drug which acts preferentially by reducing prostaglandin production within the central nervous system, and indomethacin (0.001-10 microM) caused a clear dose-dependent reduction of prostaglandin E2 production by stimulated T98G cells whereas interleukin-6 release was not affected. These data provide further evidence of the involvement of non-steroidal anti-inflammatory drugs in the inflammatory processes that can be generated by glial cells in intact brain.

Benzydamine protection in a mouse model of endotoxemia.

OBJECTIVE: Previous studies have shown that benzydamine (40 mg/kg s.c.) is able to inhibit tumor necrosis factor (TNF) production and to reduce mouse lethality when administered before or concomitantly with LPS. The present study was designed to further investigate benzydamine activity against LPS-induced toxicity in terms of potency and therapeutic effects. METHODS: Female Balb/c mice were used. A dose-response curve of animal lethality versus endotoxin dose was performed (LD50 = 45 micrograms/mouse). Therapeutic effects were studied selecting the dose of LPS to achieve an LD100 (160 micrograms/mouse). Mortality was assessed daily and mice were followed for 8 days. The potential mode of action of therapeutically administered benzydamine was also investigated. TNF alpha and IL-1 beta levels were measured, at 5 h after LPS injection, both in sera and in lungs. Moreover, the drug was assayed in a TNF-dependent cytoxicity test. RESULTS: Benzydamine, administered at 20 mg/kg s.c. simultaneously with the endotoxin, significantly increased LPS LD50 up to 230 micrograms/mouse (p < 0.05). Moreover, the drug significantly protected mice against LPS-induced lethality when administered either 30 min or 4 h after endotoxin injection (p < 0.001). Benzydamine, therapeutically administered at 20 mg/kg s.c., significantly reduced TNF alpha and IL-1 beta production induced by LPS both in serum and lungs and it was shown to inhibit TNF-dependent cytoxicity on L929 cells. CONCLUSIONS: These results clearly demonstrate the therapeutic activity of benzydamine in a simple model of endotoxic shock. Available data confirm the potential role of benzydamine as an anti-cytokine agent and provide suggestions for novel therapeutic applications of this anti-inflammatory drug.

Benzydamine inhibits the release of tumor necrosis factor-alpha and monocyte chemotactic protein-1 by Candida albicans-stimulated human peripheral blood cells.

Benzydamine is a non-steroidal antiinflammatory drug, devoid of activity on arachidonic acid metabolism, which is extensively used as a topical drug in inflammatory conditions, particularly for the treatment of bacterial vaginosis and Candida albicans-sustained vaginitis. In the present study the effects of benzydamine on the production of several inflammatory cytokines were examined in cultures of Candida albicans-stimulated human mononuclear cells. Benzydamine (6.25-50 microM) inhibited Candida-induced tumor necrosis factor-alpha and, to a lesser extent, interleukin-1 beta production, whereas it did not affect interleukin-6 release. Benzydamine also blocked monocyte chemotactic protein-1 secretion, but it did not affect interleukin-8 production. Unlike benzydamine, ibuprofen and naproxen, two non-steroidal antiinflammatory drugs also used topically, were unable to suppress inflammatory lymphokine production from Candida-activated mononuclear cells. These data suggest that benzydamine may be effective in local Candida infections at least in part by suppressing inflammatory cytokine and monokine production in the vaginal mucosa and consequently decreasing their levels in vaginal secretions.

Radical scavenger activity of bendazac, an anticataract non-steroidal anti-inflammatory agent.

Oxidative damage to lens components is associated with cataract formation and reactive oxygen species (ROS) overproduction at inflammation sites is thought to lead to the development of inflammatory disorders. Bendazac is a non-steroidal anti-inflammatory drug able to delay the cataractogenic process. Aim of the present study is to characterize, both chemically and biologically, the activity of this anticataract agent as a radical scavenger. Bendazac has been shown to be a strong reacting substrate in a chemical oxidizing system, which mimics a physiological pathway of hydroxy radical generation. In the Fenton-Cier reaction the drug rapidly forms a mixture of hydroxylated derivatives, among which 5-hydroxybendazac, bendazac's main metabolite, being a hydroxy radical scavenger itself. Moreover, by means of a rapid and sensitive flow cytometric method able to determine reactive oxygen intermediate production, bendazac and its 5-hydroxy derivative were shown to inhibit oxidative burst activation in polymorphonuclear neutrophil leukocytes (PMNLs).

Synthesis of digoxigenin-labeled cDNA as a test for mRNA integrity.

The nucleotide analogue digoxigenin-11-dUTP is widely used as a nonradioactive marker in a broad range of techniques including dot blots, Southern and Northern blots, colony and plaque screenings and in situ hybridizations. In this report, we describe the incorporation of this molecule into a cDNA synthesized by reverse transcriptase as a novel application for digoxigenin. This reaction can be performed as a useful control to check the integrity of a bulk mRNA preparation in the construction of a cDNA library, since the ability of mRNA to direct the synthesis of long molecules of first-strand cDNA is a sign of its integrity.

Decline in the exposure to hepatitis A and B infections in children in Naples, Italy.

In May 1988, the hepatitis A antibody (anti-HAV) and hepatitis B virus (HBV) markers were studied by radioimmunoassay in 484 apparently healthy children between the ages of 7 and 12, attending a primary school in Naples, Italy. The overall anti-HAV prevalence was 11.2%, increasing from 5.2 in 7-year-old children to 28.2% in children between the ages of 11 and 12 years old. The overall prevalence of the hepatitis B surface antigen (HBsAg) and of other HBV markers were 0.8 and 6.8 respectively. Compared with a similar previous study conducted in Naples in 1980, the results show a significant reduction in the prevalence of anti-HAV in each of the two age-groups (P less than 0.01), in the prevalence of any HBV marker in the 11 to 12-year-old group, as well as in the total population (P less than 0.05). The findings of the present study indicate that today, children in Naples are less exposed to the hepatitis A virus than in the past, most likely because of improvements in both the socioeconomic conditions and in health education during recent years. These same reasons, as well as decreased family size and a lower prevalence of HBeAg among HBsAg carriers could explain the decline, although to a lesser degree, of exposure to HBV infection.

Hepatitis B infections in the Arsi region of Ethiopia.

In a sample of inhabitants of the Arsi region of Ethiopia prevalence of hepatitis B is around 80% in the age group 20-24. In addition to age, sex and size of family, exposure to tribal practices is a determinant of seropositivity in this group accounting for as much as 20% of the total burden of the infection. Waiting for a mass vaccination campaign, presently unrealistic in this area of the world, health education, as part of a comprehensive primary health care program, has to be considered as a potentially effective preventive tool.