gistfile1.cs

public class Person : MyBaseClass
{
    public string Name { get; set; }
}

public class MyBaseClass : GalaSoft.MvvmLight.ViewModelBase
{
    protected virtual void Broadcast(object oldValue, object newValue, string propertyName)
    {
        var message = new PropertyChangedMessage(this, this, oldValue, newValue, propertyName);
        if (MessengerInstance != null)
        {
            MessengerInstance.Send(message);
        }
        else
        {
            GalaSoft.MvvmLight.Messaging.Messenger.Default.Send(message);
        }
    }


    protected virtual void RaisePropertyChanged(string propertyName, object oldValue, object newValue)
    {
        RaisePropertyChanged(propertyName);
        Broadcast(oldValue, newValue, propertyName);
    }
}

public class PropertyChangedMessage : GalaSoft.MvvmLight.Messaging.PropertyChangedMessageBase
{

    public PropertyChangedMessage(object sender, object target, object oldValue, object newValue, string propertyName)
        : base(sender, target, propertyName)
    {
        OldValue = oldValue;
        NewValue = newValue;
    }

    public object NewValue { get; set; }

    public object OldValue { get; set; }
}