Cardiovascular disease in obesity hypoventilation syndrome - A review of potential mechanisms and effects of therapy

Flavonoid extracts of Citrus aurantium L. var. amara Engl. Promote browning of white adipose tissue in high-fat diet-induced mice

ETHNOPHARMACOLOGICAL RELEVANCE

Obesity has become a public burden worldwide due to its booming incidence and various complications, and browning of white adipose tissue (WAT) is recognized as a hopeful strategy to combat it. Blossom of Citrus aurantium L. var. amara Engl. (CAVA) is a popular folk medicine and dietary supplement used for relieving dyspepsia, which is recorded in the Chinese Materia Medica. Our previous study showed that blossom of CAVA had anti-obesity potential, while its role in browning of WAT was still unclear.

AIM OF THE STUDY

This study aimed to characterize the constituents in flavonoids from blossom of CAVA (CAVAF) and to clarify the anti-obesity capacities especially the effects on browning of WAT.

MATERIALS AND METHODS

Gradient ethanol eluents from blossom of CAVA were obtained by AB-8 macroporous resin. 3T3-L1 cells and pancreatic lipase inhibition assay were employed to investigate the potential anti-obesity effects in vitro. HPLC and UPLC/MS assays were performed to characterize the chemical profiles of different eluents. Network pharmacology and molecular docking assays were used to reveal potential anti-obesity targets. Furthermore, high-fat diet (HFD)-induced mice were constructed to explore the anti-obesity actions and mechanisms in vivo.

RESULTS

30% ethanol eluents with high flavonoid content and great inhibition on proliferation of 3T3-L1 preadipocytes and pancreatic lipase activity were regarded as CAVAF. 19 compounds were identified in CAVAF. Network pharmacology analysis demonstrated that AMPK and PPARα were potential targets for CAVAF in alleviating obesity. Animal studies demonstrated that CAVAF intervention significantly decreased the body weight, WAT weight, serum TG, TC and LDL-C levels in HFD-fed obese mice. HFD-induced insulin resistance and morphological changes in WAT and brown adipose tissue were also markedly attenuated by CAVAF treatment. CAVAF supplementation potently inhibited iWAT inflammation by regulating IL-6, IL-1β, TNF-α and IL-10 mRNA expression in iWAT of mice. Furthermore, the gene expression levels of thermogenic markers including Cyto C, ATP synthesis, Cidea, Cox8b and especially UCP1 in iWAT of mice were significantly up-regulated by CAVAF administration. CAVAF intervention also markedly increased the expression levels of PRDM16, PGC-1α, SIRT1, AMPK-α1, PPARα and PPARγ mRNA in iWAT of mice.

CONCLUSION

CAVAF treatment significantly promoted browning of WAT in HFD-fed mice. These results suggested that flavonoid extracts from blossom of CAVA were probably promising candidates for the treatment of obesity.

Association between Previous CPAP and Comorbidities at Diagnosis of Obesity-Hypoventilation Syndrome Associated with Obstructive Sleep Apnea: A Comparative Retrospective Observational Study

Obesity-hypoventilation syndrome (OHS) is associated with many comorbidities. The aim of this study was to evaluate the association between previous continuous positive airway pressure (CPAP) and the prevalence of comorbidities in OHS associated with obstructive sleep apnea (OSA). We performed a retrospective, single-center study at the University Hospital of Martinique, the referral hospital for the island of Martinique. A total of 97 patients with OHS associated with severe OSA on non-invasive ventilation (NIV) were included; 54 patients (56%) had previous treatment of OSA with a positive airway pressure (PAP) device before shifting to NIV (PAP group) and 43 (44%) had no previous treatment of OSA with a PAP device before initiating NIV PAP (no PAP group). Sociodemographic characteristics were similar between groups; there were 40 women (74%) in the PAP group versus 34 (79%) in the no PAP group, mean age at OHS diagnosis was 66 ± 15 versus 67 ± 16 years, respectively, and the mean age at inclusion 72 ± 14 versus 71 ± 15 years, respectively. The average number of comorbidities was 4 ± 1 in the PAP group versus 4 ± 2 in the no PAP group; the mean Charlson index was 5 ± 2 in both groups. The mean BMI was 42 ± 8 kg/m2 in both groups. The mean follow-up duration was 5.8 ± 4.4 years in the PAP group versus 4.7 ± 3.5 years in the no PAP group. Chronic heart failure was less common in patients who had a previous PAP 30% versus 53% (p = 0.02). It is also noted that these patients were diagnosed less often in the context of acute respiratory failure in patients with previous PAP: 56% versus 93% (p < 0.0001). In contrast, asthma patients were more frequent in patients with previous treatment of OSA with a PAP device at the time of OHS diagnosis but not significantly: 37% versus 19% (p = 0.07). Early treatment of severe OSA with a PAP device prior to diagnosis of OHS seems to be associated with a reduced prevalence of cardiac diseases, notably chronic heart failure, in patients diagnosed with OHS associated with severe OSA.

Effects of fatty acid-ethanol amine (FA-EA) derivatives on lipid accumulation and inflammation

This study aimed to investigate the effect of fatty acid-ethanol amine (FA-EA) derivatives (L1-L10) on the mitigation of intracellular lipid accumulation and downregulation of pro-inflammatory cytokines in vitro. First, the series of FA-EA derivatives were synthesized and characterized. Then, their cytotoxic, intracellular lipid accumulation and inhibition of pro-inflammatory cytokines were evaluated. The oil red O staining experiment showed that the tested compounds L4, L6, L8, L9, and L10 could reduce intracellular lipid accumulation induced by palmitic acid (PA). Moreover, ω-3/ω-6 PUFA-EA derivatives showed inhibitory effect on the production of pro-inflammatory cytokines in lipopolysaccharide (LPS) -stimulated RAW 264.7 cells. ω-3/ω-6 PUFA-EA derivatives at a concentrations of 10 μM could significantly decrease mRNA levels of IL-6, IL-1β, and TNF-α, inhibit NO production, and alleviate the protein expression of IL-1β in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. These data suggest that ω-3 PUFA-EA derivatives can be beneficial for further pharmaceutical development to treat chronic low-grade inflammation diseases such as obesity.

A Novel Nomogram and Online Calculator for Predicting the Risk of Obesity Hypoventilation Syndrome in Bariatric Surgery Candidates

BACKGROUND

Obesity hypoventilation syndrome (OHS) is frequently misdiagnosed and undertreated, increasing the risk of perioperative complications. We aimed to determine the predictors of OHS and to develop and validate a novel nomogram and online calculator for identifying patients at risk of OHS in bariatric surgery candidates.

METHODS

We retrospectively analyzed the data of patients undergoing bariatric surgery between March 2017 and June 2020. Predictors were identified using univariate and multivariate analyses to establish the nomogram. The discriminative ability, calibration, and clinical value of the nomograms were tested using C-statistics, calibration plots, and decision curve analysis. The nomogram was internally validated using bootstrap resampling.

RESULTS

A total of 577 patients were enrolled, and OHS was presented in 17.9% (103/577). Body mass index (BMI) (odds ratio [OR], 1.11; 95% confidence interval (CI), 1.04-1.18; p = 0.001), neck circumference (OR, 1.09; 95% CI, 1.01-1.18; p = 0.035), type 2 diabetes (T2D) (OR, 2.02; 95% CI, 1.17-3.45; p = 0.011), serum bicarbonate (OR, 1.47; 95% CI, 1.30-1.67; p < 0.001), and C-reactive protein (CRP) (OR, 1.03; 95% CI, 1.01-1.06; p = 0.017) were independent risk factors for OHS and incorporated to develop the nomogram. The nomogram revealed good discrimination, with a C-index of 0.830 (95% CI: 0.784-0.876) (0.8227 through internal validation), and good calibration. Decision curve analysis further confirmed the nomogram's clinical usefulness.

CONCLUSIONS

The novel nomogram and online calculator provided an excellent preoperative individualized prediction of OHS in patients undergoing bariatric surgery, hereby potentially assisting clinicians and surgeons in the early detection and intensive monitoring of OHS.

An automated heart disease prediction approach using linearly support vector regression and stacked linear swarm optimization

In today’s world, mining and learning applications play an essential role in healthcare sectors and intend to transform all the data into an understandable form. However, the healthcare sectors require an automated disease prediction system for better medical analysis and emphasize better prediction accuracy for evaluation purposes. In this paper, a new automated prediction model based on Linearly Support Vector Regression and Stacked Linear Swarm Optimization (LSVR-SLSO) has been proposed to predict heart disease accurately. Primarily, the features are analyzed in a linear and non-linear manner using LSVR feature learning approaches. The extracted features are then fed into the SLSO model in order to extract the global optimal solutions. These global solutions will reduce the data dimensionality and computational complexity during the evaluation phase. Moreover, the optimal solution facilitates the proposed model to predict heart disease appropriately. The simulation can be carried out through the MATLAB environment by utilizing a publicly available benchmark heart disease dataset. The performance results evident that the proposed LSVR-SLSO model can efficiently predict heart disease with superior accuracy of 98%, precision of 98.76%, and recall of 99.7% when compared with conventional approaches. The better performance of the proposed model will pave the way to act as an effective clinical decision support tool for physicians during an emergency.

High-Fat Diet-Induced Mitochondrial Dysfunction Promotes Genioglossus Injury - A Potential Mechanism for Obstructive Sleep Apnea with Obesity

PURPOSE

Obesity is a worldwide metabolic disease and a critical risk factor for several chronic conditions. Obstructive sleep apnea (OSA) is an important complication of obesity. With the soaring morbidity of obesity, the prevalence of OSA has markedly increased. However, the underlying mechanism of the high relevance between obesity and OSA has not been elucidated. This study investigated the effects of obesity on the structure and function of the genioglossus to explore the possible mechanisms involved in OSA combined with obesity.

METHODS

Six-week-old male C57BL/6J mice were fed high-fat diet (HFD, 60% energy) or normal diet (Control, 10% energy) for 16 weeks. The muscle fibre structure and electromyography (EMG) activity of genioglossus were measured. The ultrastructure and function of mitochondrial, oxidative damage and apoptosis in genioglossus were detected by transmission electron microscopy (TEM), qPCR, Western blotting, immunohistochemistry and TUNEL staining. We further studied the influence of palmitic acid (PA) on the proliferation and myogenic differentiation of C2C12 myoblasts, as well as mitochondrial function, oxidative stress, and apoptosis in C2C12 myotubes.

RESULTS

Compared with the control, the number of muscle fibres was decreased, the fibre type was remarkably changed, and the EMG activity had declined in genioglossus. In addition, a HFD also reduced mitochondria quantity and function, induced excessive oxidative stress and increased apoptosis in genioglossus. In vitro, PA treatment significantly inhibited the proliferation and myogenic differentiation of C2C12 myoblasts. Moreover, PA decreased the mitochondrial membrane potential, upregulated mitochondrial reactive oxygen species (ROS) levels, and activated the mitochondrial-related apoptotic pathway in myotubes.

CONCLUSION

Our findings suggest that a HFD caused genioglossus injury in obese mice. The mitochondrial dysfunction and the accompanying oxidative stress were involved in the genioglossus injury, which may provide potential therapeutic targets for OSA with obesity.