The first thing to do is to rule out possible medical reasons for this unexpected aggression. These include neurological disorders or any disorders that could be causing chronic pain or increased irritability.
However, if this is not the case-there are many other reasons that can trigger this behaviour. He may feel threatened, challenged or fearful. He may feel territorial to certain areas of the home. His aggression towards the female (and you) may be actually coming from outside - perhaps he can see and smell other cats or a dog nearby.
An accurate diagnosis is important if the problem is to be successfully resolved. The two cats may need to be reintroduced (the same way you would introduce a new cat into the home) by separating and a slow establishment.
In the meantime, you could try a synthetic pheromone such as Feliway. This contains a synthetic copy of a feline facial pheromone that can induce a state of familiarity and security within the environment, allowing your two cats to remain calm and comfortable in each other's presence.