Sequestering HMGB1 via DNA-Conjugated Beads Ameliorates Murine Colitis

Abstract

Inflammatory bowel disease (IBD) is chronic inflammation of the gastrointestinal tract that affects millions of people worldwide. Although the etiology of IBD is not clear, it is known that products from stressed cells and enteric microbes promote intestinal inflammation. High mobility group box 1 (HMGB1), originally identified as a nuclear DNA binding protein, is a cytokine-like protein mediator implicated in infection, sterile injury, autoimmune disease, and IBD. Elevated levels of HMGB1 have been detected in inflamed human intestinal tissues and in feces of IBD patients and mouse models of colitis. Neutralizing HMGB1 activity by administration of anti-HMGB1 antibodies or HMGB1-specific antagonist improves clinical outcomes in animal models of colitis. Since HMGB1 binds to DNA with high affinity, here we developed a novel strategy to sequester HMGB1 using DNA immobilized on sepharose beads. Screening of DNA-bead constructs revealed that B2 beads, one linear form of DNA conjugated beads, bind HMGB1 with high affinity, capture HMGB1 ex vivo from endotoxin-stimulated RAW 264.7 cell supernatant and from feces of mice with colitis. Oral administration of B2 DNA beads significantly improved body weight, reduced colon injury, and suppressed colonic and circulating cytokine levels in mice with spontaneous colitis (IL-10 knockout) and with dextran sulfate sodium-induced colitis. Thus, DNA beads reduce inflammation by sequestering HMGB1 and may have therapeutic potential for the treatment of IBD.

Early life adversity in piglets induces long‐term upregulation of the enteric cholinergic nervous system and heightened, sex‐specific secretomotor neuron responses

“…Taken together, the heightened cholinergic tone induced by EWS could be an important influence in modulating life-long enteric secretory diarrheal disease severity. In addition to regulation of intestinal ion transport, it has also become evident that the cholinergic nervous system plays a major role in the regulation of GI inflammation (71, 72, 77). For example, several investigations demonstrated that vagotomized animals exhibit exaggerated dextran sulphate sodium (DSS)-induced colitis and inflammatory cytokine responses, including IL-1β, IL-6, and TNF, compared with sham controls (78, 79).…”

“…It is wellknown that the cholinergic nervous system is a major regulator of intestinal mucosal secretory mechanisms and barrier function and has received considerable attention as a critical modulator of intestinal inflammation. [67][68][69] Therefore, heightened cholinergic tone observed in EWS pigs and further investigation into the associated mechanisms could have significant impli-cations for a number of important GI diseases, especially GI diseases associated with ELA. For example, several studies have shown that cholinergic input plays a stimulatory role in infectious, secretory diarrhea as muscarinic cholinergic receptor blockade inhibited intestinal secretion induced by bacterial enterotoxins.…”

“…In addition to regulation of intestinal ion transport, it has also become evident that the cholinergic nervous system plays a major role in the regulation of GI inflammation. 68,69,74 For example, several investigations demonstrated that vagotomized animals exhibit exaggerated dextran sulfate sodium (DSS)induced colitis and inflammatory cytokine responses, including IL-1b, IL-6, and TNF, compared with sham controls. 75,76 Furthermore, it was shown that a7nicotinic receptor (a7nAchR) knock-out mice exhibit more severe DSS-induced colitis, whereas choline chloride, a a7nAchR agonist, ameliorated colitis, 76 overall indicating that the a7nAchR was a major receptor involved in the cholinergic anti-inflammatory mechanism.…”

Oral administration of geraniol ameliorates acute experimental murine colitis by inhibiting pro-inflammatory cytokines and NF-κB signaling

“…1,2 Approximately 1 in 150 people is affected with IBD in westernized nations and incidence is dramatically increasing in developing countries. 1,2 Approximately 1 in 150 people is affected with IBD in westernized nations and incidence is dramatically increasing in developing countries.…”

Role of high-mobility group box 1 protein in inflammatory bowel disease

“…It is thought that increased extracellular HMGB1 acts on epithelial and inflammatory cells, indicating an autocrine activity of the HMGB1 amplified in the intestine of IBD patients. Another study showed that infusing HMGB1 in the colon of mice resulted in a two-to threefold increase in LDH release, a marker of epithelial damage, further indicating that intraluminal HMGB1 induces tissue damage in the colon [51]. In addition, HMGB1 receptors such as TLR2 and TLR4 are also over-expressed in intestinal epithelial cells and active inflammatory cells in the intestinal mucosa of IBD patients [52].…”