Design and physicochemical characterisation of novel dissolving polymeric microneedle arrays for transdermal delivery of high dose, low molecular weight drugs

We describe formulation and evaluation of novel dissolving polymeric microneedle (MN) arrays for the facilitated delivery of low molecular weight, high dose drugs. Ibuprofen sodium was used as the model here and was successfully formulated at approximately 50% w/w in the dry state using the copolymer poly(methylvinylether/maleic acid). These MNs were robust and effectively penetrated skin in vitro, dissolving rapidly to deliver the incorporated drug. The delivery of 1.5mg ibuprofen sodium, the theoretical mass of ibuprofen sodium contained within the dry MN alone, was vastly exceeded, indicating extensive delivery of the drug loaded into the baseplates. Indeed in in vitro transdermal delivery studies, approximately 33mg (90%) of the drug initially loaded into the arrays was delivered over 24h. Iontophoresis produced no meaningful increase in delivery. Biocompatibility studies and in vivo rat skin tolerance experiments raised no concerns. The blood plasma ibuprofen sodium concentrations achieved in rats (263μgml(-1) at the 24h time point) were approximately 20 times greater than the human therapeutic plasma level. By simplistic extrapolation of average weights from rats to humans, a MN patch design of no greater than 10cm(2) could cautiously be estimated to deliver therapeutically-relevant concentrations of ibuprofen sodium in humans. This work, therefore, represents a significant progression in exploitation of MN for successful transdermal delivery of a much wider range of drugs.

Attenuation of monocyte chemotaxis--a novel anti-inflammatory mechanism of action for the cardio-protective hormone B-type natriuretic peptide

B-type natriuretic peptide (BNP) is a prognostic and diagnostic marker for heart failure (HF). An anti-inflammatory, cardio-protective role for BNP was proposed. In cardiovascular diseases including pressure overload-induced HF, perivascular inflammation and cardiac fibrosis are, in part, mediated by monocyte chemoattractant protein (MCP)1-driven monocyte migration. We aimed to determine the role of BNP in monocyte motility to MCP1. A functional BNP receptor, natriuretic peptide receptor-A (NPRA) was identified in human monocytes. BNP treatment inhibited MCP1-induced THP1 (monocytic leukemia cells) and primary monocyte chemotaxis (70 and 50 %, respectively). BNP did not interfere with MCP1 receptor expression or with calcium. BNP inhibited activation of the cytoskeletal protein RhoA in MCP1-stimulated THP1 (70 %). Finally, BNP failed to inhibit MCP1-directed motility of monocytes from patients with hypertension (n = 10) and HF (n = 6) suggesting attenuation of this anti-inflammatory mechanism in chronic heart disease. We provide novel evidence for a direct role of BNP/NPRA in opposing human monocyte migration and support a role for BNP as a cardio-protective hormone up-regulated as part of an adaptive compensatory response to combat excess inflammation.

Behavioural and histopathological analyses of ibuprofen treatment on the effect of aggregated AB (1-42) injections in the rat

It has been suggested that inflammatory processes may play a role in the development of Alzheimerâ??s disease (AD), and that nonsteroidal anti-inflammatory drug treatments may provide protection against the onset of AD. In the current study male Wistar rats were trained in two-lever operant chambers under an alternating lever cyclic-ratio ratio (ALCR) schedule. When responding showed no trends, subjects were divided into groups. One group was bilaterally injected into the CA3 area of the hippocampus with 5 μl of aggregated β-amyloid (Aβ) suspension, and one group was bilaterally injected into the CA3 area of the hippocampus with 5 μl of sterile saline. Subgroups were treated twice daily with 0.1 ml (40 mg/kg) ibuprofen administered orally. The results indicated that chronic administration of ibuprofen protected against detrimental behavioural effects following aggregated Aβ injections. Withdrawal of ibuprofen treatment from aggregated Aβ-injected subjects produced a decline in behavioural performance to the level of the non-treated aggregated Aβ-injected group. Ibuprofen treatment reduced the numbers of reactive astrocytes following aggregated Aβ injection, and withdrawal of ibuprofen resulted in an increase of reactive astrocytes. These results suggest that induced inflammatory processes may play a role in AD, and that ibuprofen treatment may protect against some of the symptoms seen in AD.

Inflammation and Anti-inflammatory strategies for alzheimer disease a mini review

Until recently, the central nervous system (CNS) has been thought to be an immune privileged organ. However, it is now understood that neuroinflammation is linked with the development of several CNS diseases including late-onset Alzheimer's disease (LOAD). The development of inflammation is a complex process involving a wide array of molecular interactions which in the CNS remains to be further characterized. The development of neuroinflammation may represent an important link between the early stages of LOAD and its pathological outcome. It is proposed that risks for LOAD, which include genetic, biological and environmental factors can each contribute to impairment of normal CNS regulation and function. The links between risk factors and the development of neuroinflammation are numerous and involve many complex interactions which contribute to vascular compromise, oxidative stress and ultimately neuroinflammation. Once this cascade of events is initiated, the process of neuroinflammation can become overactivated resulting in further cellular damage and loss of neuronal function. Additionally, neuroinflammation has been associated with the formation of amyloid plaques and neurofibrillary tangles, the pathological hallmarks of LOAD. Increased levels of inflammatory markers have been correlated with an advanced cognitive impairment. Based on this knowledge, new therapies aimed at limiting onset of neuroinflammation could arrest or even reverse the development of the disease.

Novel anti-inflammatory compound SEN1176 alleviates behavioural deficits induced following bilateral intrahippocampal injection of aggregated amyloid-beta(1-42).

Behavioral effects of a novel anti-inflammatory SEN1176 were investigated. This pyrrolo[3,2-e][1,2,4]triazolo[1,5-a]pyrimidine suppresses amyloid-ß (Aß)1-42-induced macrophage production of nitric oxide, TNF-a, IL-1ß, and IL-6 in a dose-dependent fashion, an activity profile consistent with SEN1176 being a neuroinflammation inhibitor. Using male Sprague-Dawley rats, SEN1176 was examined relative to detrimental behavioral effects induced following bilateral intrahippocampal (IH) injections of aggregated Aß1-42. The rats were trained to respond under an alternating-lever cyclic-ratio (ALCR) schedule of food reinforcement, enabling measurement of parameters of operant performance that reflect aspects of learning and memory. Under the ALCR schedule, orally administered SEN1176 at 5, 20, or 30 mg/kg was effective in reducing the behavioral deficit caused by bilateral IH aggregated Aß1-42 injections in a dose-related manner over a 90-day treatment period. SEN1176 at 20 and 30 mg/kg significantly reduced lever switching errors and, at doses of 5, 10, and 30 mg/kg, significantly reduced incorrect lever perseverations, indicating a reduction of the behavioral deficit induced as a result of inflammation following IH Aß1-42 injections. When treatment with SEN1176 was instigated 30 days after IH Aß1-42 injections, it resulted in progressive protection, and withdrawal of SEN1176 treatment 60 days after IH Aß1-42 injections revealed partial retention of the protective effect. SEN1176 also significantly reduced numbers of activated astrocytes adjacent to the aggregated Aß1-42 injection sites. These results indicate the potential of SEN1176 for alleviating chronic neuroinflammatory processes related to brain Aß deposition that affect learning and memory in Alzheimer's disease.

Anti-inflammatory effects of DX-890, a human neutrophil elastase inhibitor

Background
Neutrophil elastase (NE)-mediated inflammation contributes to lung damage in cystic fibrosis (CF). We investigated if DX-890, a small-protein NE inhibitor, could reduce neutrophil trans-epithelial migration and reduce activity released from neutrophils and NE-induced cytokine expression in airway epithelial cells.

Methods
Activated blood neutrophils (CF and healthy) treated ± DX-890 were assayed for NE activity. Transmigration of calcein-labeled neutrophils was studied using a 16HBE14o- epithelial monolayer. IL-8 release from primary nasal epithelial monolayers (CF and healthy) was measured after treatment ± DX-890 and NE or CF sputum.

Results
DX-890 reduced NE activity from neutrophils (CF and healthy) and reduced neutrophil transmigration. DX-890 pre-treatment reduced IL-8 release from epithelial cells of healthy or CF subjects after stimulation with NE and CF sputum sol. All improvements with DX-890 were statistically significant (p < 0.05).

Conclusions
DX-890 reduces NE-mediated transmigration and inflammation. NE inhibition could be useful in managing neutrophilic airway inflammation in CF.

Nonsteroidal anti-inflammatory drugs and the esophageal inflammation-metaplasia-adenocarcinoma sequence

Observational studies suggest that nonsteroidal anti-inflammatory drugs (NSAIDs) reduce the risk of esophageal adenocarcinoma, but it is not known at what stage they may act in the esophageal inflammation-metaplasia-adenocarcinoma sequence. In an all-Ireland case-control study, we investigated the relationship between the use of NSAIDs and risk of reflux esophagitis, Barrett's esophagus, and esophageal adenocarcinoma. Patients with esophageal adenocarcinoma, long-segment Barrett's esophagus and population controls were recruited from throughout Ireland. Esophagitis patients were recruited from Northern Ireland only. Data were collected on known and potential risk factors for esophageal adenocarcinoma and on the use of NSAIDs, including aspirin, at least 1 year before interview. Associations between use of NSAIDs and the stages of the esophageal inflammation-metaplasia-adenocarcinoma sequence were estimated by multiple logistic regression. In total, 230 reflux esophagitis, 224 Barrett's esophagus, and 227 esophageal adenocarcinoma and 260 population controls were recruited. Use of aspirin and NSAIDs was associated with a reduced risk of Barrett's esophagus [odds ratio [OR; 95% confidence interval (95% CI)], 0.53 (0.31-0.90) and 0.40 (0.19-0.81), respectively] and esophageal adenocarcinoma [OR (95% CI), 0.57 (0.36-0.93) and 0.58 (0.31-1.08), respectively]. Barrett's esophagus and esophageal adenocarcinoma patients were less likely than controls to have used NSAIDs. Selection or recall bias may explain these results and the results of previous observational studies indicating a protective effect of NSAIDs against esophageal adenocarcinoma. If NSAIDs have a true protective effect on the esophageal inflammation-metaplasia-adenocarcinoma sequence, they may act early in the sequence.

Docosahexaenoic acid induces an anti-inflammatory profile in lipopolysaccharide-stimulated human THP-1 macrophages more effectively than eicosapentaenoic acid

A number of studies have investigated the effects of fish oil on the production of pro-inflammatory cytokines using peripheral blood mononuclear cell models. The majority of these studies have employed heterogeneous blends of long-chain n-3 polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which preclude examination of the individual effects of LC n-3 PUFA. This study investigated the differential effects of pure EPA and DHA on cytokine expression and nuclear factor kappaB (NF-kappaB) activation in human THP-1 monocyte-derived macrophages. Pretreatment with 100 microM EPA and DHA significantly decreased lipopolysaccharide (LPS)-stimulated THP-1 macrophage tumor necrosis factor (TNF) alpha, interleukin (IL) 1beta and IL-6 production (P