Director of Communications
Institute for Biomedical Sciences
Georgia State University
ATLANTA—Dr. Didier Merlin, a Distinguished University Professor in the Institute for Biomedical Sciences at Georgia State University and a Senior Research Career Scientist at VA Medical Center, is available to discuss his research on developing new drug delivery platforms to treat inflammatory bowel disease (IBD) and colorectal cancer using nanotechnology approaches.
Over one million adults and children in the United States, including members of the VA population, suffer from IBD, with about 50,000 new cases diagnosed each year. Inflammation, especially chronic inflammation such as IBD, plays a key role in the development of colorectal cancer. According to the Crohn’s and Colitis Foundation of America, IBD patients from the VA have a much higher rate of colorectal cancer compared to the general population. Based on data from the National Center for Health Statistics, 2.9 percent of VA patients develop colorectal cancer versus 0.1 percent of the general population.
“I believe nanotechnology offers a promising future that can help treat medical conditions such as IBD, where certain medications have limited applications due to inherent side effects,” Merlin said. “Because this is an evolving science, more studies are required to identify the nanoparticles’ pharmacokinetics, therapeutic efficacy and safety in humans.”
Merlin’s research accomplishments are well recognized in the field of gastroenterology. He has produced more than 200 publications in reputable journals and has been cited extensively, achieving an h-index of 70 with a total of 13,951 citations.
In the past decade, molecularly targeted therapeutic approaches have been developed based on the pathophysiology of inflammatory responses in IBD. Pro-inflammatory cytokines, such as TNF-α inhibitors, are among the most potent drugs currently available to treat IBD, but these drugs need to be administered systemically and their use is limited by serious side effects. Therefore, there is an unmet need for a targeted carrier system capable of delivering low doses of a drug specifically and effectively to inflamed colonic regions over a prolonged period. Such a system could significantly reduce side effects that limit existing treatments.
Nanotechnology is predicted to be one of the key technologies of the 21st century. Particles, in the size of nanometers, can be used to deliver medications directly to the area of inflammation thus avoiding drug-associated systemic side effects. When using nanoparticles, only a small amount of the drug is needed, and it can be delivered directly to the inflamed site without exposure to the rest of the body.
Merlin’s laboratory has demonstrated that oral administration of artificially synthesized nanoparticles and nano lipids may be used to target low doses of biological therapeutics, such as small inhibitory RNAs (siRNAs), mRNAs, proteins and peptides, to specific colonic cell types (such as epithelial cells and macrophages) and reduce intestinal inflammation in mice with colitis.
New treatments that can target gut microbiota to either restore healthy gut microbiota composition or reverse irregular gut microbiota might be an alternative, independent or complementary means to traditional treatment. Current methods require a long treatment time and often give delayed therapeutic efficacy. There is an urgent need for a drug delivery platform that can rapidly change microbiota composition while not generating severe side effects to the host’s gut microenvironment.
In his latest study published in the journal Pharmaceutics in August, Merlin found orally delivered nano lipid-loaded drugs instantly changed the composition of gut microbiota in mice, which created functional changes and might be a powerful tool for treating ulcerative colitis.
“The possibility of using lipid nanoparticles to target specific bacteria and deliver small molecules that can affect the function of these bacteria could offer a new therapeutic strategy for switching an inflammatory microbiota to a non-inflammatory microbiota and could be a solution for IBD patients,” Merlin said. “Further mechanistic studies should be performed to characterize anti-inflammatory metabolites that could be used in targeting nanotechnology-based delivery platforms for the treatment of IBD.”
Distinguished University Professor
Institute for Biomedical Sciences
Research interests: Cell biology, Digestive diseases, Nanomedicine in intestinal inflammation