Endotoxin Biomarkers Are Associated With Adiposity and Cardiometabolic Risk Across 6 Years of Follow-up in Youth

Endotoxin biomarkers, hepatic fat fraction, liver volume and liver stiffness among adolescents at high-risk for non-alcoholic fatty liver disease: The HEROES study

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is on the rise among youth. Identifying biomarkers of NAFLD progression/risk can aid in prevention efforts.

AIMS

This pilot study investigated associations of two endotoxin biomarkers-lipopolysaccharide-binding protein (LBP) and anti-endotoxin core immunoglobulin G (EndoCab)-with markers of NAFLD among 99 Latino/Latina adolescents (11-19 years) with obesity.

MATERIALS & METHODS

We used linear regression to examine associations of each endotoxin biomarker (per 1-SD) with hepatic fat fraction (HFF), liver volume, and liver stiffness.

RESULTS

We found positive associations of LBP with HFF and liver volume. Each 1-SD increment in LBP corresponded with 2.35% (95% CI: 0.46%, 4.23%) higher HFF and 0.14 (0.06, 0.23) L greater liver volume after adjusting for age, sex, and maternal education. Accounting for abdominal adiposity and Tanner stage did not change results. Excluding 72 participants with NAFLD attenuated associations of LBP with HFF but associations with liver volume persisted (0.11 [0.01, 0.21] L). EndoCab was not associated with any liver outcomes. Neither endotoxin biomarker predicted liver stiffness.

DISCUSSION/CONCLUSION

While additional research is warranted, our results support LBP as a biomarker of NAFLD risk/progression in high-risk youth.

Reduced Lipopolysaccharide-Binding Protein (LBP) Levels Are Associated with Non-Alcoholic Fatty Liver Disease (NAFLD) and Adipose Inflammation in Human Obesity

Lipopolysaccharide (LPS) and its binding protein LBP have emerged as potential contributors to the progression from overweight/obesity to overt metabolic diseases and NAFLD. While LPS is known to activate hepatocyte inflammation, thus contributing toward NAFLD development, the role of LBP is more intricate, and recent data have shown that experimental reduction in hepatic LBP promotes NAFLD progression. In this cross-sectional investigation, we evaluated circulating LBP in relation to obesity, NAFLD, visceral adipose tissue (VAT) inflammation, and type 2 diabetes (T2D). We recruited 186 individuals (M/F: 81/105; age: 47 ± 10.4 years; BMI: 35.5 ± 8.6 kg/m2); a subgroup (n = 81) underwent bariatric surgery with intra-operative VAT and liver biopsies. LBP levels were higher in obese individuals than non-obese individuals but were inversely correlated with the parameters of glucose metabolism. Reduced LBP predicted T2D independent of age, sex, and BMI (p < 0.001). LBP levels decreased across more severe stages of hepatosteatosis and lobular inflammation, and were inversely associated with VAT inflammation signatures. In conclusion, LBP levels are increased in obese individuals and are associated with a more favorable metabolic profile and lower NAFLD/NASH prevalence. A possible explanation for these findings is that hepatic LBP production may be triggered by chronic caloric excess and facilitate LPS degradation in the liver, thus protecting these individuals from the metabolic consequences of obesity.

Clinical and pathological characteristics of DKD patients with early-onset type 2 diabetes

AIMS

In diabetic kidney disease (DKD) patients, early-onset T2DM effects on renal disease severity and outcomes remain uncertain. Herein, we aim to investigate the clinicopathological characteristics and renal outcomes in DKD patients with early-onset T2DM.

METHODS

489 patients with T2DM and DKD were retrospectively recruited and classified as having early (age at onset of T2DM < 40 years) and late (age at onset of T2DM ≥ 40 years) T2DM onset, analyzing the clinical and histopathological data. The predictive value of early-onset T2DM to renal outcomes in DKD patients was analyzed by Cox's regression.

RESULTS

Among 489 DKD patients, 142 and 347 were classified as early and late T2DM onset, respectively. Early-onset T2DM patients exhibited worse glycaemic control (7.36 % ± 1.80 % vs. 6.86 % ± 1.57 %, P = 0.007) and more severe proteinuria (3.69 [1.55 to 7.03] vs. 1.81 [0.50 to 4.33] g/24 h, P < 0.001). Those with early-onset T2DM presented more severe glomerular lesions. In univariable Cox regression, early-onset T2DM showed a significant correlation with renal composite endpoint (HR [95%CI]: 0.56 [0.43 to 0.73], P < 0.001). However, after adjusting for potential confounders, early-onset T2DM was not independently correlated with renal composite endpoint (HR [95%CI]: 0.74 [0.46 to 1.21], P = 0.232).

CONCLUSIONS

In DKD patients with early-onset T2DM, renal clinicopathological manifestations were severe. Age at onset in T2DM was significantly correlated with eGFR slope (r = 0.211, P < 0.001).

Low Grade Endotoxemia and Oxidative Stress in Offspring of Patients with Early Myocardial Infarction

Background and aims: Offspring of patients with early myocardial infarction are at higher cardiovascular risk, but the underlying physio-pathological mechanism is unclear. NADPH oxidase-type 2 (NOX-2) plays a pivotal role as mediator of oxidative stress and could be involved in activating platelets in these patients. Furthermore, altered intestinal permeability and serum lipopolysaccharide (LPS) could be a trigger to promote NOX-2 activation and platelet aggregation. This study aims to evaluate the behavior of low grade endotoxemia, oxidative stress and platelet activation in offspring of patients with early myocardial infarction. Methods: We enrolled, in a cross-sectional study, 46 offspring of patients with early myocardial infarction and 86 healthy subjects (HS). LPS levels and gut permeability (assessed by zonulin), oxidative stress (assessed by serum NOX-2-derived peptide (sNOX2-dp) release, hydrogen peroxide (H₂O₂) production and isoprostanes), serum nitric oxide (NO) bioavailability and platelet activation (by serum thromboxane B2 (TXB2) and soluble P-Selectin (sP-Selectin)) were analyzed. Results: Compared to HS, offspring of patients with early myocardial infarction had higher values of LPS, zonulin, serum isoprostanes, sNOX2-dp H₂O₂, TXB2, p-selectin and lower NO bioavailability. Logistic regression analysis showed that the variables associated with offspring of patients with early myocardial infarction were LPS, TXB2 and isoprostanes. The multiple linear regression analysis confirmed that serum NOX-2, isoprostanes, p-selectin and H₂O₂ levels were significantly associated to LPS. Furthermore, serum LPS, isoprostanes and TXB2 levels were significantly associated with sNOX-2-dp. Conclusions: Offspring of patients with early myocardial infarction have a low grade endotoxemia that could generate oxidative stress and platelet activation increasing their cardiovascular risk. Future studies are needed to understand the role of dysbiosis in this population.