Pro-inflammatory and pro-resolving lipid mediators of inflammation in HIV: effect of aspirin intervention

Specialized pro-resolving lipid mediators in gut immunophysiology: from dietary precursors to inflammation resolution

PURPOSE OF REVIEW

This review aims to examine recent research on the role of specialized pro-resolving mediators (SPMs) in the regulation of gut immunophysiology.

RECENT FINDINGS

Inflammatory bowel disease (IBD) is characterized by chronic inflammation in the gastrointestinal tract, driven by disruptions in the intestinal barrier and an imbalance between the host immune system and gut microbiota. Dietary polyunsaturated fatty acids (PUFAs), especially ω-3 and ω-6, are key regulators of immune responses and help maintain the integrity of the intestinal barrier. These PUFAs serve as precursors to SPMs, lipid mediators that play a critical role in resolving inflammation. SPMs actively reprogram immune cells, promoting the clearance of cellular debris, reducing cytokine production, and restoring tissue homeostasis without suppressing the immune response. Emerging evidence indicates that in the gut, SPMs strengthen intestinal barrier function, modulate immune responses in colitis and colon cancer, and influence gut microbiota composition.

SUMMARY

The recent evidence strongly supports the central role of SPMs in maintaining gut health and restoring organ function following inflammatory challenges. This evidence highlights the potential of therapeutic approaches that target these pathways for both the prevention and treatment of gut-related inflammatory conditions.

Distinct metabolic perturbations link liver steatosis and incident CVD in lean but not obese PWH

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a key risk factor for cardiovascular disease (CVD), potentially driven by shared metabolic mechanisms. Metabolic perturbations associated with MASLD and CVD remain underexplored in people with HIV (PWH).

METHODS

We used data from the longitudinal multicenter 2000HIV study comprising 1895 virally suppressed PWH, out of which 970 had available liver and carotid artery measurements. Transient elastography with controlled attenuation parameter (CAP) was performed for the assessment of liver steatosis (CAP > 263 dB/m) and fibrosis (LSM ≥ 7.0). Historic and future incident CVD within 2-year follow-up, defined as myocardial infarction, stroke, peripheral arterial disease, and angina pectoris, were extracted from the medical files, while atherosclerotic plaque(s) in the carotid arteries were assessed using ultrasonography. Metabolic perturbations were analyzed using mass spectrometry-based untargeted metabolomics (n = 500 metabolites) and nuclear magnetic resonance spectroscopy for targeted lipids and other metabolites (n = 246 metabolites).

RESULTS

PWH with liver steatosis were more likely to have arterial plaques (47% vs. 36%; P value = 0.003) and CVD history (11% vs. 6.8%; P value = 0.021) than PWH without liver steatosis. These associations were only significant in lean PWH, in contrast to those with BMI ≥ 25 kg/m2. Metabolic pathways associated with liver steatosis and fibrosis primarily involved lipid and amino acid metabolism, and they were validated by targeted lipoproteomic measurements. Interestingly, metabolomic pathways and lipoproteomic signatures associated with MASLD were mostly distinct from those associated with CVD parameters. However, several metabolic pathways were shared, especially in lean PWH. These include arachidonic acid metabolism and formation of prostaglandin, purine metabolism, cholecalciferol metabolism, and glycine, serine, alanine, and threonine metabolism.

CONCLUSION

Metabolic disturbances linked to liver steatosis and CVD diverge across BMI categories in PWH. Lean PWH, unlike their overweight/obese counterparts, show common metabolic perturbations between MASLD and CVD, particularly involving arachidonic acid metabolism. This suggests that lean PWH with liver steatosis may face a heightened risk of CVD due to shared metabolic pathways, potentially opening avenues for targeted interventions, such as aspirin therapy, to mitigate this risk.

Thrombotic microenvironment responsive crosslinking cyclodextrin metal-organic framework nanocarriers for precise targeting and thrombolysis

Global public health is seriously threatened by thrombotic disorders because of their high rates of mortality and disability. Most thrombolytic agents, especially protein-based pharmaceuticals, have a short half-life in circulation, reducing their effectiveness in thrombolysis. The creation of an intelligent drug delivery system that delivers medication precisely and releases it under regulated conditions at nearby thrombus sites is essential for effective thrombolysis. In this article, we present a unique medication delivery system (MCRUA) that selectively targets platelets and releases drugs by stimulation from the thrombus' microenvironment. The thrombolytic enzyme urokinase-type plasminogen-activator (uPA) and the anti-inflammatory medication Aspirin (acetylsalicylic acid, ASA) are both loaded onto pH-sensitive CaCO3/cyclodextrin crosslinking metal-organic frameworks (MC) that make up the MCRUA system. c(RGD) is functionalized on the surface of MC, which is functionalized by RGD to an esterification reaction. Additionally, the thrombus site's acidic microenvironment causes MCRUA to disintegrate to release uPA for thrombolysis and aiding in vessel recanalization. Moreover, cyclodextrin-encapsulated ASA enables the treatment of the inflammatory environment within the thrombus, enhancing the antiplatelet aggregation effects and promoting cooperative thrombolysis therapy. When used for thrombotic disorders, our drug delivery system (MCRUA) promotes thrombolysis, suppresses rethrombosis, and enhances biosafety with fewer hemorrhagic side effects.

Metabolic adaptations in severe obesity: Insights from circulating oxylipins before and after weight loss

BACKGROUND

The relationship between lipid mediators and severe obesity remains unclear. Our study investigates the impact of severe obesity on plasma concentrations of oxylipins and fatty acids and explores the consequences of weight loss.

METHODS

In the clinical trial identifier NCT05554224 study, 116 patients with severe obesity and 63 overweight/obese healthy controls matched for age and sex (≈2:1) provided plasma. To assess the effect of surgically induced weight loss, we requested paired plasma samples from 44 patients undergoing laparoscopic sleeve gastrectomy one year after the procedure. Oxylipins were measured using ultra-high-pressure liquid chromatography coupled to a triple quadrupole mass spectrometer via semi-targeted lipidomics. Cytokines and markers of interorgan crosstalk were measured using enzyme-linked immunosorbent assays.

RESULTS

We observed significantly elevated levels of circulating fatty acids and oxylipins in patients with severe obesity compared to their metabolically healthier overweight/obese counterparts. Our findings indicated that sex and liver disease were not confounding factors, but we observed weak correlations in plasma with circulating adipokines, suggesting the influence of adipose tissue. Importantly, while weight loss restored the balance in circulating fatty acids, it did not fully normalize the oxylipin profile. Before surgery, oxylipins derived from lipoxygenase activity, such as 12-HETE, 11-HDoHE, 14-HDoHE, and 12-HEPE, were predominant. However, one year following laparoscopic sleeve gastrectomy, we observed a complex shift in the oxylipin profile, favoring species from the cyclooxygenase pathway, particularly proinflammatory prostanoids like TXB2, PGE2, PGD2, and 12-HHTrE. This transformation appears to be linked to a reduction in adiposity, underscoring the role of lipid turnover in the development of metabolic disorders associated with severe obesity.

CONCLUSIONS

Despite the reduction in fatty acid levels associated with weight loss, the oxylipin profile shifts towards a predominance of more proinflammatory species. These observations underscore the significance of seeking mechanistic approaches to address severe obesity and emphasize the importance of closely monitoring the metabolic adaptations after weight loss.

Pharmacokinetics and Changes in Lipid Mediator Profiling after Consumption of Specialized Pro-Resolving Lipid-Mediator-Enriched Marine Oil in Healthy Subjects

Omega-3 polyunsaturated fatty acids (PUFAs) play a vital role in human health, well-being, and the management of inflammatory diseases. Insufficient intake of omega-3 is linked to disease development. Specialized pro-resolving mediators (SPMs) are derived from omega-3 PUFAs and expedite the resolution of inflammation. They fall into categories known as resolvins, maresins, protectins, and lipoxins. The actions of SPMs in the resolution of inflammation involve restricting neutrophil infiltration, facilitating the removal of apoptotic cells and cellular debris, promoting efferocytosis and phagocytosis, counteracting the production of pro-inflammatory molecules like chemokines and cytokines, and encouraging a pro-resolving macrophage phenotype. This is an experimental pilot study in which ten healthy subjects were enrolled and received a single dose of 6 g of an oral SPM-enriched marine oil emulsion. Peripheral blood was collected at baseline, 3, 6, 9, 12, and 24 h post-administration. Temporal increases in plasma and serum SPM levels were found by using LC-MS/MS lipid profiling. Additionally, we characterized the temporal increases in omega-3 levels and established fundamental pharmacokinetics in both aforementioned matrices. These findings provide substantial evidence of the time-dependent elevation of SPMs, reinforcing the notion that oral supplementation with SPM-enriched products represents a valuable source of essential bioactive SPMs.