Rising Inflammatory Bowel Disease Prevalence Highlights the Need for Effective, Cost-Effective Therapies

Cardiovascular Comorbidities and Inflammatory Bowel Disease: Causes and Consequences

Patients with inflammatory bowel disease (IBD) have an increased risk of cardiovascular disease (CVD) such as myocardial infarction and stroke. CVD in patients with IBD might occur in those with younger age and active disease, which are not traditional risk factors of CVD. Atherosclerotic CVD (ASCVD) and IBD are both proinflammatory conditions, and the underlying chronic inflammation might drive ASCVD risk. Decreasing inflammation might reduce this risk; however, data are limited. IBD medications can increase or decrease ASCVD risk. There are no specific guidelines or modalities to assess ASCVD in IBD. Early detection and risk stratification strategies have been established in other chronic inflammatory disorders. This article discusses causes of CVD in IBD and strategies to modify the consequences.

Coronary artery calcium scoring for cardiovascular risk assessment in patients with inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease (IBD) is associated with higher incidence of atherosclerotic cardiovascular disease (ASCVD). Data investigating the role of coronary artery calcium (CAC) scoring in identifying subclinical atherosclerotic disease in IBD patients is scarce.

METHODS

Using data obtained from the CLARIFY registry, a prospective study of no-charge coronary artery calcium (CAC) testing at University Hospitals, we reviewed patients with ulcerative colitis (UC) or Crohn's disease (CD) who underwent CAC scoring from 2014 to 2020. We investigated the concordance between CAC risk and 10-year estimated ASCVD risk by AHA/ACC pooled cohort equation using pre-established thresholds for statin prescription (CAC≥100, 10-year ASCVD risk ≥7.5%). We additionally investigated the association between CAC, preventive therapy initiation and Major Adverse Cardiovascular Events (MACE).

RESULTS

A total of 369 patients with IBD were included (174 UC, 195 CD), with median age of 60 years. The median CAC score was 14.9 with no significant difference between UC and CD (P = .76). Overall, 151 (41%) had CAC of 0, 108 (29%) had CAC 1-99, 61 (17%) had CAC 100 to 399, and 49 (13%) had CAC ≥400 with no difference in CAC distribution between CD and UC (P = .17). There was no difference in median CAC between IBD or age/sex-matched controls (P = .34). Approximately half of the patients (52%) with IBD had 10-year estimated ASCVD risk of 7.5% or higher. Among patients with ASCVD risk <7.5% (n = 163), 29 (18%) had CAC≥100 and among patients with ASCVD risk ≥7.5% (n = 178), 102 (57%) had CAC <100. There was no difference between CAC<100 vs CAC≥100 with respect to CRP, use of immunosuppressive or amino-salicylate therapy, IBD severity or complications. CAC score (AUROC 0.67 [0.56-0.78]), but not PCE ASCVD risk (AUROC 0.60 [0.48-0.73]), was predictive of MACE. The best cut-off for CAC score was 76 (sensitivity = 60%, specificity = 69%), and was associated with 4-fold increase in MACE (Hazard Ratio 4.0 [2.0-8.1], P < .001).

CONCLUSION

Subclinical atherosclerosis, as evaluated by CAC scoring, is prevalent in patients with IBD, and is associated with cardiovascular events. Further studies are needed to understand underlying biological processes of increased atherosclerotic disease risk among adults with IBD.

Discovery of a Bromodomain and Extra Terminal Domain (BET) Inhibitor with the Selectivity for the Second Bromodomain (BD2) and the Capacity for the Treatment of Inflammatory Diseases

Selective inhibitors targeting the first bromodomain (BD1) or the second bromodomain (BD2) of the bromodomain and extra terminal domain (BET) proteins have triggered extensive research to produce more specific agents. Herein, we described our efforts to design and synthesize a series of selective BET BD2 inhibitors with novel structures. Among them, compound 45 showed single-digit nanomolar potency against BRD4 BD2 (IC50: 1.6 nM) and a 328-fold selectivity for BRD4 BD2 over BRD4 BD1 (IC50: 524 nM). Besides, 45 possessed potent effects on regulating the differentiation of Th17 cells and reducing the levels of Th17-related cytokines by affecting the activation of STAT3 and NF-κB. Further studies demonstrated that 45 had significant therapeutic efficacy in mouse models of imiquimod (IMQ)-induced psoriasis and dextran sulfate sodium (DSS)-induced inflammatory bowel disease (IBD). This work provides a strong foundation for the development of selective BET BD2 inhibitors and the therapeutic strategy for psoriasis and IBD.

Clinical Significance of Serum Elafin in Children with Inflammatory Bowel Disease

BACKGROUND

The role of elafin in the pathophysiology of inflammatory bowel disease (IBD) has not been not elucidated. We aimed to evaluate serum elafin in children with IBD and assess its relationship with disease activity.

METHODS

We enrolled children with IBD in the study group and children with functional abdominal pain in the control group. We evaluated serum elafin using enzyme-linked immunosorbent assay kits.

RESULTS

In children with IBD, serum elafin (mean ± SD: 4.192 ± 1.424 ng/mL) was significantly elevated compared with controls (mean ± SD: 3.029 ± 1.366 ng/mL) (p = 0.0005). Elafin was significantly increased in children in the active phase of IBD (mean ± SD: 4.424 ± 1.449 ng/mL) compared with the control group (p = 0.0003). In IBD remission, only children with ulcerative colitis (mean ± SD: 4.054 ± 1.536 ng/mL) had elevated elafin compared with controls (p = 0.004). ROC analysis revealed that the area under the curve (AUC) of serum elafin was 0.809 while discriminating patients with ulcerative colitis from the control group, and the AUC was 0.664 while differentiating patients with Crohn's disease from the control group.

CONCLUSIONS

Serum elafin was found to be elevated in our cohort of children with IBD, depending on disease activity. Serum elafin was increased in the active phases of both ulcerative colitis and Crohn's disease, but only in the remission of ulcerative colitis. Elafin appears to be a potential candidate for a biomarker of ulcerative colitis.

Starch nanoparticles improve curcumin-induced production of anti-inflammatory cytokines in intestinal epithelial cells

Inflammatory bowel disease (IBD), encompassing Crohn's disease and ulcerative colitis, is a long-term condition resulting from self-sustained intestinal inflammation. Curcumin (Cur), a powerful, naturally occurring antioxidant and anti-inflammatory polyphenol, has been investigated as a therapeutic for IBD, but its poor stability and low bioavailability limits its efficacy. We investigated the use of crosslinked starch nanocarrier (NPL) on the intracellular delivery and the anti-inflammatory efficiency of curcumin. Caco-2 epithelial cells were stimulated with TNFα for 24 h and the anti-inflammatory effects of NPL/Cur formulations were evaluated at the early stages of inflammation (4 h) or later, when fully established (24 h). NPL allowed the intracellular delivery of curcumin, which was enhanced in inflammatory cells, due to a modification of the endocytosis pathways. NPL/Cur decreased the secretion of pro-inflammatory cytokines IL-1β, IL-6 and IL-8 while increasing the anti-inflammatory cytokine IL-10. Finally, the inflammation-related opening of the tight junctions better allowed NPL/Cur to cross the epithelium by paracellular transport. This was confirmed by ex vivo analysis where NPL/Cur, administered to colonic explants from chemically-induced acute colitis mouse model, delivered curcumin deeper in the epithelium. To conclude, NPL/Cur formulation emphasizes the anti-inflammatory effects of curcumin and could constitute a therapeutic alternative in the management of IBD.

Pioglitazone-Mediated Attenuation of Experimental Colitis Relies on Cleaving of Annexin A1 Released by Macrophages

Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases (IBDs) which burden health systems worldwide; available pharmacological therapies are limited and cost-intensive. Use of peroxisome proliferator activated-receptor γ (PPARγ) ligands for IBD treatment, while promising, lacks solid evidences to ensure its efficacy. Annexin A1 (AnxA1), a glucocorticoid-modulated anti-inflammatory protein, plays a key role on IBD control and is a potential biomarker of IBD progression. We here investigated whether effects of pioglitazone, a PPARγ ligand, rely on AnxA1 actions to modulate IBD inflammation. Experimental colitis was evoked by 2% dextran sodium sulfate (DSS) in AnxA1 knockout (AnxA1^-/-) or wild type (WT) C57BL/6 mice. Clinical and histological parameters were more severe for AnxA^-/- than WT mice, and 10 mg/kg pioglitazone treatment attenuated disease parameters in WT mice only. AnxA1 expression was increased in tissue sections of diseased WT mice, correlating positively with presence of CD68⁺ macrophages. Metalloproteinase-9 (MMP-9) and inactive 33 kDa AnxA1 levels were increased in the colon of diseased WT mice, which were reduced by pioglitazone treatment. Cytokine secretion, reactive oxygen species generation and MMP-9 expression caused by lipopolysaccharide (LPS) treatment in AnxA1-expressing RAW 264.7 macrophages were reduced by pioglitazone treatment, effects not detected in AnxA1 knockdown macrophages. LPS-mediated increase of AnxA1 cleaving in RAW 264.7 macrophages was also attenuated by pioglitazone treatment. Finally, pioglitazone treatment increased extracellular signal-regulated kinase (ERK) phosphorylation in AnxA1-expressing RAW 264.7 macrophages, but not in AnxA1-knockdown macrophages. Thus, our data highlight AnxA1 as a crucial factor for the therapeutic actions of pioglitazone on IBDs.