Bra entrepreneur Michelle Mone and her husband, Michael, are risking their personal wealth to expand their high-profile lingerie business, it has emerged.

The pair have given unlimited personal financial guarantees for bank loans made to their Govan-headquartered MJM International company.

MJM, which appears modestly profitable, ended the 2006 financial year with assets worth £2.7m, including cash and stock. However, the company also owed its creditors £2.2m repayable within 12 months.

MJM's website advertises Michelle Mone as "one of the world's leading and successful professionals". However, only a limited amount is known about her company because its accounts are filed under Companies Act provisions allowing small firms to publish abbreviated statements.

MJM's latest figures do show that the Mones owed the company £167,381 at the financial year end on April 30, 2006. In January this year they took a dividend of £170,000 out of the business and used the money to repay that loan. "In addition," the annual report adds, "Michael and Michelle Mone have provided unlimited personal guarantees as security for bank borrowings to HSBC." These guarantees are not mentioned in the accounts for the previous year.

MJM did not respond to a request for comment yesterday. In a recent interview, however, 35-year-old Ms Mone admitted MJM had its problems four years ago and that the couple nearly lost their house. "We've turned it round and we're now Europe's biggest independent designer lingerie company," she was quoted as saying, adding that the business is now debt free.

She also said there were plans to move from the cramped HQ in Govan to larger premises near East Kilbride this summer.

Last week she received planning consent from South Lanarkshire Council to build a five-bedroom villa at Thorntonhall, near Eaglesham, by South Lanarkshire Council. The £2m plans include a swimming pool and cinema.

Her latest venture is a herbal slimming pill developed by the herbalist Jan De Vries, for which she acted as a human guinea pig. They plan to launch the product next month.

Ms Mone credited the pills for helping her achieve a dramatic weight loss. From being a size 20 a year ago she has lost four-and-a-half stone.

The pill, taken twice a day in conjunction with a healthy eating plan and drinking 1.5 litres of water a day, "transformed everything", she said.

After bouncing from the Atkins diet, to WeightWatchers, to Slimmers World she consulted Mr De Vries, who had already begun work on a weight-loss pill for his clients.

"When you are on a diet you are depressed and deprived, but with these pills I had lots of energy. It gives you loads of energy, suppresses your appetite and burns cellulite - it has certainly burned mine," she said.

MJM has 43 staff in Glasgow and about 50 in Hong Kong with five brands - Ultimo, Young Attitude, Michelle at George, Per Amore and Adore Moi. Her latest invention is the first 24-hour bra for Asda in the Michelle for George range.

Mone's latest big-name model signing for Ultimo is Sarah Harding from Girls Aloud, following in the footsteps of Helena Christensen, Rachel Hunter and Penny Lancaster.

The company suffered a difficult time five years ago after withdrawing its products from retail outlets, complaining about the high mark-ups taken by stores, but they reverted to over-the-counter sales after an internet selling venture produced disappointing results.