Technically, you need an investor and not a lender. Only they are able to take your idea/product into consideration and give you money as venture capitalists. They definitely take interests and company shares just like you expect. However, lenders on bitcointalk will have zero clues about the future of your company or product or the market to take that risk. Company shares can be valid collateral if they a high value in the market already just like a very good alt-coin.