SELECT DATE_FORMAT(date_time, '%Y-%m-%d %H:%i:%s') AS formatted_date_time FROM my_table;

string formattedDateTime = reader["formatted_date_time"].ToString();
DateTime dateTime = DateTime.ParseExact(formattedDateTime, "yyyy-MM-dd HH:mm:ss", null);

public static DateTime ParseMySQLDateTime(string mySQLDateTime)
{
    DateTime dateTime = default(DateTime);
    if (!string.IsNullOrEmpty(mySQLDateTime) && DateTime.TryParseExact(mySQLDateTime, "yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture, DateTimeStyles.None, out dateTime))
    {
        return dateTime;
    }
    else
    {
        return default(DateTime);
    }
}

DateTime dateTime = ParseMySQLDateTime(reader["date_time"].ToString());