win-54954 and Myocarditis

Cardiomyocyte apoptosis (CA) is known to occur in experimental coxsackievirus B3 (CVB3) myocarditis. However, the mechanisms of CA induction are not well known. In this study we investigate the role of direct viral induction of CA in CVB3 myocarditis.. A/J mice were infected with the Woodruff strain of CVB3 and treated with WIN 54954 for 5 days thereafter. WIN 54954, a compound that inhibits early events of picornavirus infection, is known to dramatically reduce mortality in murine CVB3 myocarditis without abrogating systemic or myocardial inflammation. Presence of viral RNA (in situ hybridization), CA (TUNEL method) and histopathology were studied in transverse ventricular sections at day 7 post infection (n = 8 treated and n = 8 non-treated).. The proportion of cardiomyocytes containing viral RNA was 89% lower in WIN 54954 treated mice when compared with non-treated mice (0.29 +/- 0.56% vs 2.76 +/- 1.65%, p = 0.003). Treatment also reduced the amount of CA by 52% compared with non-treated mice (0.20 +/- 0.06% vs 0.42 +/- 0.06%, p < 0.001). The reduction of CA by WIN treatment did not result in any increase of necrosis, in fact treatment reduced the area of necrotic lesions by 77% (2.51 +/- 1.64% vs 11.10 +/- 8.76%, p = 0.028).. Taking the results of the reduced CA, necrosis and viral RNA with no effect on inflammation into account, our findings suggest the importance of direct viral effect in cardiomyocyte damage by both apoptosis and necrosis in CVB3 myocarditis.

Topics: Animals; Antiviral Agents; Apoptosis; Enterovirus B, Human; Enterovirus Infections; Heart Ventricles; Isoxazoles; Mice; Mice, Inbred Strains; Myocarditis; Myocardium; Necrosis

Coxsackieviruses B (CBVs) are dominant causative agents in myocarditis and are associated with pathogenesis is some cases of dilated cardiomyopathy, a clinical entity with a poor survival without heart transplantation.. In vitro, the antiviral agent WIN 54 954 was shown to inhibit replication of CBV3 at a minimal inhibitory concentration value of 0.02 mg/L. Administration of WIN 54 954, 100 mg/kg BID PO, beginning on the day of infection resulted in complete protection from enteroviral mortality (P < .01). WIN 54 954 treatment did not abrogate the inflammatory reaction in the myocardium. No difference was found in the expression of surface lymphocyte subset markers. At 3 weeks, macrophages seemed to dominate the inflammatory reaction, regardless of treatment. There was no difference in CBV3 antibody titers, indicating that WIN 54 954 does not interfere with the development of protective immunity. Complement factors C3 and B were synthesized at a higher level during infection and correlated well with the degree of inflammatory reaction.. The results show that WIN 54 954 is a potent antiviral agent with a highly significant effect on survival in CBV-induced myocarditis in the A/J mouse if treatment is started early. It is suggested that the reduction in mortality seen with WIN 54 954 administration is due to an inhibitory effect on virus replication in affected organs that does not interfere with cellular or humoral immunity.

Topics: Animals; Antibodies, Viral; Antiviral Agents; Blotting, Northern; Complement C3; Complement Factor B; Complement System Proteins; Coxsackievirus Infections; Enterovirus; Enterovirus B, Human; Isoxazoles; Male; Mice; Mice, Inbred A; Mice, Inbred BALB C; Mice, Inbred CBA; Myocarditis; Neutralization Tests; RNA, Messenger; Survival Analysis

The antiviral efficacy of WIN 54954 was demonstrated in vivo in a Coxsackie B 3 virus (Woodruff strain) induced myocarditis mouse model. The model was selected because of the high mortality rate during the first week, which was convenient for antiviral therapy regimen studies. The antiviral component WIN 54954 was found to inhibit the early virus-induced mortality almost completely if treatment was started at the same time as virus was inoculated. However, there was still a late mortality, occurring at 1-2 months after virus inoculation. Non-infected mice which were treated with the drug did not show any such late effects. However, drug treatment in non-infected mice did not cause any mortality. When therapy was delayed for one day, 85% survived for 3 weeks as compared to 100% mortality after just over 3 weeks in the infected control group (p < 0.05). With a delay of 4 days after viral inoculation, a therapeutic effect was still noted. Thus, mortality was virtually abrogated when the compound was given early, but the effect vanished with time of delay. Different preparations of the WIN 54954 substance were tried, and it was found that a fat emulsion containing several nutrients (Nutrodrip) was superior to other used formulations. We conclude that the use of the antiviral drug WIN 54954 in treatment of enteroviral associated diseases is of great value if therapy is started early. Thus therapy is almost fully effective within 24 hours of infection, but the beneficial effects decline with time. Nutrodrip oil emulsion was found superior as vehicle as compared to other formulations.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Antiviral Agents; Coxsackievirus Infections; Dosage Forms; Enterovirus B, Human; Female; Isoxazoles; Mice; Mice, Inbred BALB C; Myocarditis; Pharmaceutical Vehicles

The effects of the anti picornaviral drug WIN 54954 (5-(5-(2.6-dichloro-4-(4.5-dihydro-2-oxazolyl)phenoxy)pentyl)-3-me thyl- isoxazole) and the immune modulator LS 2616 (Quinoline-3-carboxamide) on plasma cachectin/TNFa and g-interferon (IFN-g) responses were investigated during the clinical course of a myocarditic coxsackievirus B3 (CB3) infection in the mouse. Virus as well as inflammatory and necrotic lesions were found in the hearts on days 4 and 7 post inoculation (p.i.), respectively. This was demonstrated using in situ virus RNA hybridization and immune histological techniques with monoclonal antibodies against lymphocyte subsets. The CB3 infection increased TNFa levels during the first three days of disease. This response was suppressed by WIN 54954 and LS 2616. IFN-g was decreased in infected mice in the late phase of the disease (day 11). Therapy, however, was protective, and WIN 54954 even tended to increase the IFN-g response at day 5, corresponding to the time when viremia peaks. These results indicate that cytokines may serve as prognostic markers in the therapy of infectious diseases and also that WIN 54954 and LS 2616 are both possible candidates for treatment of coxsackievirus infections in man. It is suggested that a combined antiviral and immune stimulatory treatment could be of future value.

Topics: Adjuvants, Immunologic; Animals; Antiviral Agents; Coxsackievirus Infections; Enterovirus B, Human; Female; Hydroxyquinolines; Interferon-gamma; Isoxazoles; Mice; Mice, Inbred BALB C; Myocarditis; Tumor Necrosis Factor-alpha

The therapeutic efficacy of an experimental antiviral agent, WIN 54954, was evaluated in murine myocardial infection with coxsackievirus A9 (CVA9). Eight-month-old male Swiss Webster mice were inoculated with 1.5 x 10(4) PFU of CVA9, Boston strain 13. WIN 54954, a broad-spectrum antipicornavirus agent, was administered orally in a dose of 0.25, 2.5, 25, 50, 100, or 200 mg/kg of body weight per day on days 1 to 3 after virus inoculation. Control animals received xanthan gum carrier only. Mice were sacrificed on day 4. Myocardial titers of virus were determined and found to be significantly lower in the four highest dose treatment groups (P less than 0.001 for all groups) compared with controls. Heart weights were also significantly lower compared with controls in these four groups (P less than 0.001 for all groups). When mice received 50 mg of WIN 54954 per kg daily beginning at either 48 or 72 h postinoculation, myocardial titers were once again significantly reduced compared with those of controls (P less than 0.001 for both groups). Neurological toxicity was observed in the 100- and 200-mg/kg/day groups but not in the lower-dose groups. Thus, WIN 54954 effectively reduced myocardial CVA9 replication in a murine model.

Topics: Animals; Antiviral Agents; Coxsackievirus Infections; Enterovirus; Isoxazoles; Male; Mice; Myocarditis; Myocardium; Organ Size