This is the third in a series of articles from the winners of the 2011 Dow Sustainability Innovation Student Challenge Awards. Read the first two here and here. What is sustainable chemistry or green chemistry? It is normally recognized as a chemical philosophy of designing environmentally friendly processes and minimizing waste or pollution. Biotechnology also contributes in creating green chemistry. One project which the Peking University research team has been working on for the International Genetically Engineered Machine competition (iGEM 2010 Peking Team), is developing a bacteria-based heavy metal detecting, accumulating and recycling bio-kit, which is an example of realizing green chemistry goals through utilizing biological methods.
However, green chemistry is much more than simply reducing waste or improving the efficiency of reactions. It also includes fundamental scientific discoveries which in turn enhance the "green-ness" of other fields. Through effective interaction with related areas, the sustainable nature of green chemistry may now be found throughout the developed world, becoming a routine aspect of daily life.
Our project for the Dow Sustainability Innovation Student Challenge focuses on sustainability within the human body itself, which is, sustainable healthcare. Sustainable healthcare, or ecologically sustainable medicine (ESM), is defined by the long-term maintenance of health which depends on the regular maintenance of environmental health and the rational use of natural resources. As sustainable chemistry is based on the concept of “minimizing waste by not producing it at the source,” the major purpose of sustainable healthcare is to prevent disease beforehand instead of curing it afterwards. This coincides with the time-honored Chinese saying: “The greatest doctor cures disease before it ever develops.”
The two primary principles in sustainable healthcare are as follows:
1. Medical treatment aims at maximizing human health. This requires a comprehensive understanding of new medical technologies. It makes use of its positive effects while minimizing its negative effects. For example, the widespread drug-resistant bacterial infection caused by the overuse of antibiotics is a side-effect of inadequately considering the negative impact of antibiotics.
2. Medical treatment is economically sustainable, i.e., the cost is minimized. Medical science develops relatively inexpensive, efficient drugs and treatment to meet the basic needs of all patients. The focus of medicine also shifts from curing to the prevention of disease. For example, the conventional treatment for diabetic patients is long-term insulin medication, rather than addressing the root cause of diabetes. That burdens patients both physically and financially through solely focusing on the disease itself while ignoring the patient's fundamental needs.
In our project, we demonstrate two examples for each principle of sustainable healthcare, both realized by a result of chemical research.
Reactive oxygen species (ROS) are regarded as the root cause of many chronic diseases. Among them, organic hydroperoxides (OHPs) are the major agent responsible for most types of damage in the human body, which may be regarded as a conglomerate of organic molecules. We developed a protein-based probe, OHSer, to selectively detect OHPs in vivo. Its value in sustainable healthcare has been demonstrated by two specific applications.
Antibiotic resistance
Antibiotic resistance has been recognized as one of the world’s most pressing public health problems. According to the U.S. Centers for Disease Control and Prevention, antibiotic resistant infections in the United States are responsible for $20 billion excess healthcare costs, $35 billion societal costs and eight million additional hospital days. This problem is more severe in China, with mortality in the hundreds of thousands and annual increases in the numbers of handicapped patients due to such infections. The key for treating antibiotic resistant infections is to use appropriate types and dosages of antibiotics according to the varying characteristics of the different infections, instead of overdosing as a standard protocol.
We developed a system for optimizing the antibiotic selection process for clinical practitioners. Utilizing OHSer, we observed that bacteria antibiotic resistance was directly linked with their OHP production when drugged. Therefore, when dealing with a specific kind of infection, we initially determined the minimal effective concentration of various antibiotics. We subsequently exposed bacteria to the antibiotic sets and screened the amount of bacterial OHP production utilizing OHSer. The antibiotic which induces the least OHP production is the optimal one, as it is least likely to trigger resistance. Accordingly, clinical practitioners will be able to prescribe the appropriate type and dosage of antibiotic according to the different kinds of infection.
Type 2 diabetes
Diabetes is the world’s ninth leading cause of death, with such potentially lethal complications as stroke and coronary disease. According to WHO, 346 million patients worldwide are afflicted with diabetes, including 25.8 million in the United States. More than 80 percent of diabetes deaths occur in low- and middle-income countries. China has the dubious distinction of having the greatest number of diabetes patients, 100 million.
Type 2 diabetes accounts for more than 90 percent of all diagnosed cases of diabetes. Its characteristics include impaired glucose metabolism and pancreatic dysfunction. Through the use of OHSer, we discovered that a high concentration of glucose significantly increased the OHP level in cell nuclei, causing cellular abnormality and apoptosis. Therefore, the “silver bullet” for targeting the root cause rather than the symptoms of diabetes may be an effective nucleus-targeting antioxidant treatment. By protecting nuclear DNA from oxidative damage from the outset, subsequent cell death and organ dysfunction may be avoided, and the progression of diabetes may be eventually prevented or reversed. Effective antioxidants would be efficiently selected by screening with OHSer. Such treatment would likely cost much less than life-long insulin medication and would certainly be far more convenient from the perspective of patients.
The principles of green chemistry are directly tied to sustainable healthcare as well as to cognate fields linked to human life.
Think ahead, beware in time and keep in mind: prevention is more sustainable than solution. That’s the core of a sustainable life.
Zhao Boxuan is an undergraduate student at the College of Chemistry and Molecular Engineering at Peking University, China. His research interests include protein engineering and the physiological roles of small molecules. He is the president of the Life Sciences Industry Association of Peking University, an active student association dedicated to bridging the gap between university students and industry professionals, as well as advocating green ideas and technology. Boxuan was honored with the Dow Sustainability Innovation Student Challenge Awards at Peking University in 2011.
