Sphingolipid profiles and their relationship with inflammatory factors in asthmatic patients of different sexes

Background

Asthma is a heterogeneous disease with distinct prevalence and manifestation between sexes. This study was to identify sex-specific features of asthma via metabolomic analysis of sphingolipids.

Methods

Forty-two asthma patients (27 women and 15 men) admitted to the Peking University Third Hospital from January 2015 to December 2015 were enrolled. Peripheral venous blood was collected for metabolomic analysis by targeted liquid chromatography-mass spectrometry. Sex hormones(estradiol, progesterone, testosterone, and androstenedione) and multiple inflammatory factors (periostin, leptin, IgE, IL-4, IL-5, IL-10, IL-13, IL-17A, and IFN-γ) were also assessed. The eosinophil percentage in induced sputum was also detected. All these data were applied to comparative analysis between sexes.

Results

Testosterone was negatively related to periostin (ρ = −0.420, P = 0.009) and IL-5 (ρ = −0.540, P = 0.012), while estradiol was positively related to the blood eosinophil percentage (ρ = 0.384, P = 0.025). Among the eighteen species of sphingolipids detected in the 42 patients, five ceramide (Cer) species (Cer16:0, Cer:20:0, Cer22:0, Cer24:0, and Cer26:0) and one sphingomyelin (SM) species (SM38:0) were significantly higher in male than in female patients. Further investigation found that the correlation between Cer20:0 and IL-5 was positive in males (ρ = 0.943, P = 0.005) but negative in females (ρ = −0.561, P = 0.030).

Conclusions

Testosterone was negatively correlated with eosinophil inflammatory factors, but estradiol was positively correlated. Male asthma patients had higher ceramide and sphingomyelin levels than female patients. Different sexes had opposite correlations with ceramide and IL-5, respectively, suggesting that therapeutic strategies targeting ceramide should be different between sexes.

Serum Glycerophospholipid Profile in Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Studies have shown that glycerophospholipids are involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). This study adopted targeted metabolomic analysis to investigate the changes in serum glycerophospholipids in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and their differential expression in patients with different inflammatory subtypes. Patients with AECOPD admitted between January 2015 and December 2017 were enrolled, and their clinical data were collected. The patients' gender, age, body mass index, and lung function were recorded. Routine blood and induced sputum tests were performed. Liquid chromatography-mass spectrometry was used to detect the serum glycerophospholipid metabolic profiles and to analyze the metabolic profile changes between the acute exacerbation and recovery stages as well as the differences between different inflammatory subtypes. A total of 58 patients were hospitalized for AECOPD, including 49 male patients with a mean age of 74.8 ± 10.0 years. In the metabolic profiles, the expression of lysophosphatidylcholine (LPC) 18:3, lysophosphatidylethanolamine (LPE) 16:1, and phosphatidylinositol (PI) 32:1 was significantly reduced in the acute exacerbation stage compared to the recovery stage (P < 0.05). The three glycerophospholipids were used to plot the receiver operating characteristic curves to predict the acute exacerbation/recovery stage, and the areas under the curves were all above 70%. There were no differential metabolites between the two groups of patients with blood eosinophil percentage (EOS%) ≥2% and <2% at exacerbation. The expression of LPC 18:3, LPE 16:1, and PI 32:1 was significantly reduced in the acute exacerbation stage compared to the recovery stage in the inflammatory subtype with blood EOS <2% (P < 0.05). Abnormalities in the metabolism of glycerophospholipids may be involved in the onset of AECOPD, especially in the non-eosinophilic subtype.

Metabolomic Analysis of Serum Glycerophospholipid Levels in Eosinophilic and Neutrophilic Asthma

OBJECTIVE

To compare the serum glycerophospholipid levels in the inflammatory subtypes of asthma by using targeted metabolomic analysis.

METHODS

Demographic and clinical data were collected from 51 patients with asthma between January 2015 and December 2015. Routine blood and sputum induction tests were performed. Eosinophilic asthma was defined as induced sputum containing ⪖ 3% eosinophils, and neutrophilic asthma, as induced sputum containing ⪖ 71% neutrophils. Serum metabolic glycerophospholipid profile was determined by liquid chromatography-mass spectrometry. Differences in glycerophospholipid levels between eosinophilic and non-eosinophilic asthma and between neutrophilic and non-neutrophilic asthma were analyzed using partial least squares discriminant analysis.

RESULTS

The serum lysophosphatidylglycerol level was significantly higher in the group with ⪖ 3% eosinophils in sputum than in the group with < 3% eosinophils in sputum. The area under the receiver-operating characteristic curve was ⪖ 70%. There was no significant difference in the serum metabolic glycerophospholipid profile between the group with sputum neutrophils ⪖ 71% and the group with sputum neutrophils < 71%.

CONCLUSION

Serum lysophosphatidylglycerol is produced abundantly in eosinophilic asthma and may be a biomarker of eosinophilic asthma. This information is helpful for identifying and tailoring treatment for the common asthma subtypes.

Adipose-Derived Stem Cells Enhance Bone Regeneration in Vascular Necrosis of the Femoral Head in the Rabbit

Osteonecrosis of the femoral head was induced in rabbits by intramuscular injection of methylprednisolone and vascular occlusion of the capital femoral epiphysis by electrocoagulation. Eight weeks later the animals received no treatment (group A), core decompression by drilling a hole (diameter 1.2 mm) from the outer cortex 2.5 cm distal to the proximal end of the greater trochanter (group B), or injection of 107 autologous adipose-derived stem cells (ADSCs) directly into the femoral head (group C). Eight weeks later, microcomputed tomography scans indicated that bone and trabecular volume and density were significantly higher in group C than in other groups. Histology indicated more new bone formation in group C than in other groups. Group C showed strong osteocalcin immunoreactivity in subchondral bone osteoblasts in the necrotic femoral head, whereas few osteocalcin-positive cells were found among osteoblasts in other groups. Thus, autologous ADSC transplantation improved osteogenesis and the microstructure of vascular deprivation-induced osteonecrotic tissue.