$HOST = "localhost";
$USER = "root";
$PASS = "";
$DB = "banco";

function conexao(){
    try{
        include_once("defines.php");
        $conn = new PDO("mysql:host=".$HOST.";dbname=".$DB."",$USER,$PASS);
    }catch(PDOException $e){
        $e->getMessage();
    }
    return $conn;
}

include "po/config.php";
$conn = conexao ();

function notícias($conn){
    // Faz algo
}