Scientists at the University of Bonn believe that sunflowers can produce a substance which prevents HIV from reproducing, at least in cell cultures. The substance is Dicaffeoyl quinic acid (DCQA), which has already been separately identified by other researchers as a possible foundation for a new group of powerful AIDS drugs. One of the stumbling blocks in developing these new drugs, however, is the astronomical cost of DCQA - over US$1 million per gram (around US$30 million per once). The researchers in Bonn believe that their discovery of sunflower derived DCQA could slash the costs of the substance. The researcher who discovered the potential new source of DCQA is agricultural engineer Claudio Cerboncini. Cerboncini found that some sunflowers can fight off a destructive mold called white stem rot by producing antibodies which stop the fungus. He isolated these antibodies and found that one of the components was DCQA.
DCQA was previously obtained from the artichoke and wild chicory, but only in extremely small doses, hence the high cost.
"We want to attempt to cultivate sunflower cells or other plant cells in a nutrient solution together with the mold and then obtain the enzyme from the liquid," explained co-researcher Ralf Theisen. "If things go according to plan, we could produce DCQA at a substantially reduced cost."
Cerboncini added that DCQA is one of the few substances known today which inhibit viral integrase - an enzyme which is essential for HIV to reproduce. "In contrast to other enzymes, medical experts expect there to be only a few side-effects from such integrase inhibitors. In the pharmaceuticals industry they are therefore seen as the great white hope for a completely new class of AIDS drugs. Initial clinical tests seem to confirm DCQA's potential," he said.
But much work still needs to be done to produce DCQA cost-effectively from sunflowers. Finding out which genes the sunflowers activate when they produce DCQA in reaction to a fungus infection is the first important step. "The plants probably only have one enzyme, which acts as a catalyst for this transfer. If we can find the construction manual for this enzyme, [that is] the corresponding gene, [we] can produce the enzyme in large quantities. The critical step of synthesis would then be child's play and could be carried out on an industrial basis," summarized Theisen.
Even if DCQA can be produced cost-effectively, there is no guarantee that the results in the laboratory will be replicated in the real world. "We need these substances to expand our arsenal of effective weapons against the disease," said Dr. Esther Vogt of the Bonn University Clinic. "It remains to be seen, however, whether they will prove to be as effective in clinical practice as they seem to be at present."
Based on material from the University of Bonn
