Tumor necrosis factor-a antisense transfer remarkably improves hepatic graft viability

Ex vivo transfer of nuclear factor-kappaB decoy ameliorates hepatic cold ischemia/reperfusion injury

Cold ischemia/reperfusion injury of the hepatic graft has been attributed to the release of various inflammatory cytokines. Specific inhibition of these cytokines may improve viability of the hepatic graft upon reperfusion. Herein we have assessed the efficacy of cis element decoy against nuclear factor-kappaB binding site delivery to the hepatic tissue in a rodent liver transplantation model. At 8 hours after reperfusion of the liver, significant reduction was noted in the livers treated with decoy in the release of cytosolic enzymes from the hepatocytes and in serum tumor necrosis factor alpha (P < .05). The neutrophilic infiltration into the hepatic grafts was significantly suppressed in the livers treated with decoy oligodeoxynucleotides (ODNs). Decoy ODNs against nuclear factor-kappaB binding site delivery improved the viability of the hepatic graft against cold ischemia/reperfusion injury in the rodent liver transplantation model.

Reduction of liver tumor necrosis factor-alpha expression by targeting delivery of antisense oligonucleotides into Kupffer cells protects rats from fulminant hepatitis

BACKGROUND

Fulminant liver failure can cause extreme mortality due to the lack of effective and targeting therapeutics for the disease. Novel therapeutics using antisense technology require an efficient and safe delivery system with Kupffer cell targeting ability.

METHODS

We explored the capacity of galactosylated low molecular weight chitosan (GLC) to efficiently mediate the antisense oligonucleotide (ASO) TJU-2755 into Kupffer cells, enhance the effect of the oligonucleotides on the suppression of tumor necrosis factor (TNF)-alpha and prolong the active time of the antisense drug in vivo. The protective and therapeutic effect of ASO/GLC in the animal model of D-galactosamine/lipopolysaccharide-induced fulminant hepatitis was tested.

RESULTS

ASOs delivered by GLC were concentrated in Kupffer cells and more potent in reducing the expression of TNF-alpha mRNA, as well as reducing serum TNF-alpha levels. Furthermore, the ASO/GLC complex successfully rescued animals from fulminant hepatitis and mortality. Compared to naked ASO, the complex notably reduced the dose administrated in animals and prolonged its effectiveness. A single dose of 5 mg ASO per kg body weight achieved a satisfactory effect after 5 days, and 20 mg ASO per kg body weight preserved 70% of the effect after more than 2 weeks. Its efficacy was affirmed through both pretreatment and therapeutic use after liver damage had begun.

CONCLUSIONS

Inhibiting TNF-alpha expression in the liver by this strategy represents a novel therapeutic approach that may be valuable for the treatment of some inflammation-related liver diseases.

Platelets promote liver regeneration under conditions of Kupffer cell depletion after hepatectomy in mice

BACKGROUND

Platelets have been proven to promote liver regeneration after hepatectomy. Kupffer cells produce inflammatory cytokines and also promote liver regeneration. In the present study, we examined whether platelets promote liver regeneration after hepatectomy under conditions of Kupffer cell depletion.

METHODS

Seventy percent hepatectomy was carried out in mice, which were subsequently divided into four groups: (1) a normal group without any treatment, (2) a Kupffer cell depleted (KD) group, (3) a thrombocytotic group, and (4) a combined thrombocytotic and Kupffer cell depleted (TKD) group. Growth kinetics in the liver regeneration, growth factors, inflammatory cytokines, and signal transduction relating to hepatocyte proliferation were analyzed.

RESULTS

In the KD group, liver regeneration was significantly delayed compared to the normal group 48 h after hepatectomy. On the other hand, liver regeneration of the TKD group increased significantly compared to KD group, to a level that was the same as that recorded in the normal group. In the thrombocytotic group, liver regeneration increased significantly compared to the normal group. Tumor necrosis factor alpha (TNF-alpha) expression was lower in the KD and TKD groups than in the normal group after hepatectomy, but, in the TKD group, hepatocyte growth factor and Akt phosphorylation were higher than in the normal and KD groups.

CONCLUSIONS

After hepatectomy, liver regeneration in the Kupffer cell depleted group was delayed because of lower TNF-alpha expression. Platelets promote liver regeneration even under condition of Kupffer cell depletion by stimulating hepatocyte growth factor and insulin-like growth factor-1 expression, and they activate Akt.

Inhibition of laminin-8 in vivo using a novel poly(malic acid)-based carrier reduces glioma angiogenesis

We have previously shown that laminin-8, a vascular basement membrane component, was overexpressed in human glioblastomas multiforme and their adjacent tissues compared to normal brain. Increased laminin-8 correlated with shorter glioblastoma recurrence time and poor patient survival making it a potential marker for glioblastoma diagnostics and prediction of disease outcome. However, laminin-8 therapeutic potential was unknown because the technology of blocking the expression of multi-chain complex proteins was not yet developed. To inhibit the expression of laminin-8 constituents in glioblastoma in vitro and in vivo, we used Polycefin, a bioconjugate drug delivery system based on slime-mold Physarum polycephalum-derived poly(malic acid). It carries an attached transferrin receptor antibody to target tumor cells and to deliver two conjugated morpholino antisense oligonucleotides against laminin-8 alpha4 and beta1 chains. Polycefin efficiently inhibited the expression of both laminin-8 chains by cultured glioblastoma cells. Intracranial Polycefin treatment of human U87MG glioblastoma-bearing nude rats reduced incorporation of both tumor-derived laminin-8 chains into vascular basement membranes. Polycefin was thus able to simultaneously inhibit the expression of two different chains of a complex protein. The treatment also significantly reduced tumor microvessel density (p < 0.001) and area (p < 0.001) and increased animal survival (p < 0.0004). These data suggest that laminin-8 may be important for glioblastoma angiogenesis. Polycefin, a versatile nanoscale drug delivery system, was suitable for in vivo delivery of two antisense oligonucleotides to brain tumor cells causing a reduction of glioblastoma angiogenesis and an increase of animal survival. This system may hold promise for future clinical applications.