Does changes in pH affects cyclic form of glucose in water solution?

Glucose in water solution is mainly in cyclic form. Both base and acid can catalize formation of hemiacetal, but in distinct mechanisms. I found information that monosacharides eg. glucose exist mainly in cyclic form under neutral pH eg. human organism pH~7,40, but in alkaline and acidic environment chain becomes open and open chain is the form that is most abundant under this conditions. Is that true and if it is how it can be explained?