The microvilli (just like the microvilli in the intestines) in the proximal convoluted tubule of the nephron, functions to increase the surface area of the tubule leading to a more efficient reabsorption process (as the PCT functionally functions to reabsorb solutes such as sodium, potassium, and glucose).
The question here is, is glucose a protein? No, it's not; it's a carbohydrate.
So pepsin would not break it down: it would most probably not react with glucose at all, since pepsin breaks down proteins, not carbohydrates. <span />
Cell, the smallest unit that can exist independently