Instead of buying new items, it is a good idea to reuse what you already have. For example, if you are going to ship something to a friend or relative who lives out of state, it is a good idea to re-use a box and packing materials from an item that you had shipped to you previously.
Well, research has found that the same can be done with pharmaceuticals that are already available and known compounds.
Scientists at Wayne State University in Michigan have identified three non-antibiotic drugs that can protect the eye from inflammation during a bacterial infection. They are Dequalinium chloride, Clofilium tosylate and Glybenclamide and they can be used in addition to standard antibiotic therapy to minimize infection after eye surgery.
A common infection after eye surgery is Staphylococcus aureus-induced endophthalmitis. This infection occurs when bacteria from the outside affects the inner eye. This infection can lead to blindness, if not treated promptly. Currently, management of this complication involves antibiotic therapy, which kills the microbe, but doesn’t reduce inflammation. To top it off, 50 percent of the infections are caused by different antibiotic-resistant strains of the bacteria, which can lead to treatment failure and blindness.
Scientists tested the effectiveness of the three drugs and found that all showed anti-inflammatory properties against antibiotic-sensitive and resistant bacterial strains in human cultured retinal cells. In addition, Dequalinium chloride, Clofilium tosylate and Glybenclamide worked well with the antibiotic vancomycin. Researchers are looking into the mechanisms that underlie the antimicrobial and anti-inflammatory properties of these drugs and they want to test them against other bacteria to explain the crosstalk between the drugs, the host and the microbe.
What about known compounds, like enzymes? Scientists at the Medical College of Georgia did a study that was published in the journal Cell Death and Disease and Cells about the enzyme, arginase 1 or A1. The research showed evidence that having more of this enzyme available interrupts responses that lead to inflammation in both diabetic retinopathy and retinopathy of prematurity.
What leads to less inflammation is making less of the amino acid L-arginine available. In the case of diabetes, high blood sugar, lipid level and oxidative stress increase inducible nitric oxide synthase or iNOS, which uses L-arginine to make more inflammation and this leads to disease progression. What is supposed to happen is that the levels of iNOS go up in response to an infection and A1 cells come in to turn off the iNOS and have inflammation go down.
Since A1 competes with iNOS for L-arginine, researchers theorized that more A1, which breaks down L-arginine into two products, would make less L-arginine available to supply materials for the iNOS explosion and shut down the cycle of inflammation and related damage. So, if the L-arginine levels are reduced, iNOS can’t work and this makes things better.
In fact, when a diabetic, obese lab mouse developed a condition similar to early-stage diabetic retinopathy was given A1 three times a week for two weeks, its visual acuity improved and it was better able to distinguish shades of grey. The reason for this was that the mouse had less oxidative stress and inflammation in the retina and the repair of the protective blood retinal barrier helped to avoid leakage of the capillaries, as well as the swelling and damage that as a result of the slowing down of the progression of diabetic retinopathy.
A1’s anti-inflammatory ability is shown in the way it can keep immune cells, which can promote and reduce inflammation, from becoming too pro-inflammatory. While other antioxidants and anti-inflammatory substances have been tried and haven’t worked, this research shows that A1 is able to reduce the ability to make iNOS in big amounts. Researchers have also found that A1 can penetrate the eye, which makes shots directly into the eye unnecessary. In comparison, Anti-VEGF therapy is done with injection into the back of the eye.
Reuse and recycling does more than just reduce waste. It plays an important role in both developing treatments for eye infections and in biomedical research.