* Intu shares up 27 pct (Adds fund manager quote, short positions, updates share price): (Reuters) - Intu Properties (INTUP.L) shares jumped more than 27 percent on Friday, lifted by news of a potential cash takeover offer for the business as it grapples with a downturn in Britain’s bricks-and-mortar retail sector. A consortium comprising Peel Group, Saudi Arabia’s Olayan and property investor Brookfield Asset Management (BAMa.TO) announced late on Thursday that it was considering a bid for Intu, the CEO of which stepped down in July when it swung to a loss and warned of lower growth in rental income.