High serum total bilirubin as a protective factor against hip bone loss in healthy middle-aged men

Association of urinary bisphenols with oxidative stress and inflammatory markers and their role in obesity

Bisphenol A (BPA) and its substitutes are widely used in daily life. Animal and cell line experiments have confirmed the effects of bisphenols on oxidative stress and inflammation. However, current population evidence for the effects of BPA alternatives, such as bisphenol F (BPF) and bisphenol S (BPS), on oxidative stress and inflammation is still sparse. Based on the National Health and Nutrition Examination Survey 2013-2016 data, our study used linear regression, weighted quantile sum model, and Bayesian kernel machine regression model to evaluate the effects of BPA, BPS, and BPF alone and in combination on oxidative stress (serum total bilirubin, and iron) and inflammation (alkaline phosphatase, C-reactive protein, γ-glutamyl transferase ferritin, neutrophil count, lymphocyte count, and neutrophil-to-lymphocyte ratio) markers. On this basis, the possible roles of oxidative stress and inflammation in obesity, which is associated with exposure to bisphenols (BPs), were initially explored. Based on the different covariates selected, a total of 3039 and 2258 participants were included in our study for models 1 and 2, respectively; the median age of participants was 48 years, and 48.7 % were male. Based on all models, our results showed that exposure to BPs alone or in combination was associated with downregulation of serum total bilirubin. Urinary BPF concentration was specifically associated with the neutrophil-to-lymphocyte ratio. Serum total bilirubin may play a role in the association between obesity and BP mixture exposure. Upregulation of the neutrophil-to-lymphocyte ratio was not associated with obesity. In conclusion, our study found that single or combined exposure to BPs, as measured in urine, may be associated with changes in oxidative stress and inflammatory markers, and a decrease in serum total bilirubin may play a mediating role in BP-induced obesity.

Association between total bilirubin and bone mineral density level in adolescents

Background

Increasing bone mass accumulation in adolescence and obtaining greater peak bone mass is one of the effective methods to prevent osteoporosis in the future. We aimed to examine the association between total bilirubin and bone mineral density (BMD) level in adolescents.

Methods

We used the data from 2005–2010 and 2013–2014 cycles of National Health and Nutrition Examination Survey (NHANES). The BMD levels in the region of lumbar spine and femoral regions, including total femur, femoral neck, trochanter, and intertrochanter were measured. Univariable and multivariable linear regression model were used to assess the relationship between total bilirubin concentration and BMD.

Results

A total of 3741 participants aged 12–19 years were ultimately included in the study. There were 1997 (53.38%) males and 1744 (46.62%) females. Univariate analysis results showed that age, sex, race, education, income, body mass index, dietary calcium intake, and diabetes were correlated with BMD levels. Compared with the lowest quartile of total bilirubin concentration, the highest quartile of total bilirubin concentration was positively associated with BMD levels in the regions of total femur (β = 0.036, 95% CI = 0.021 to 0.050, P < 0.001), femur neck (β = 0.030, 95% CI = 0.016 to 0.044, P < 0.001), trochanter (β = 0.033, 95% CI = 0.019 to 0.046, P < 0.001), intertrochanter (β = 0.040, 95% CI = 0.023 to 0.056, P < 0.001), and lumbar spine (β = 0.032, 95% CI = 0.018 to 0.045, P < 0.001). We also observe the same trend in sensitivity analysis (P for trend < 0.001).

Conclusion

Our study demonstrated that total bilirubin concentration was positively associated with BMD levels in adolescents in United States. Total bilirubin concentration might be a protective marker against bone loss in adolescents.

Relationship of Bone Status with Serum Uric Acid and Bilirubin in Men with Type 2 Diabetes: A Cross-Sectional Study

Background

Accumulating evidence has shown that serum uric acid and bilirubin are associated with some chronic diseases, owing to their antioxidant capacity, but the previous research produced discrepant results regarding the relation between uric acid, as well as bilirubin, and bone health. This study was designed to assess the relationship of serum uric acid and total bilirubin with bone mineral density and bone turnover markers in men with type 2 diabetes.

Material/Methods

In total, 631 male patients with type 2 diabetes were included. Data of patients’ medical history, biochemical index, bone mineral density of the lumbar vertebra, femoral neck, and total hip, and bone turnover markers including osteocalcin (OC), amino-terminal propeptide of type I procollagen (PINP), type I collagen carboxy-terminal peptide (CTX), and parathyroid hormone were collected and retrospectively analyzed.

Results

Both serum uric acid and total bilirubin were positively related to bone mineral density of the lumbar vertebra (β=0.179, p<0.001; β=0.095, p=0.030), femoral neck (β=0.133, p=0.002; β=0.089, p=0.029), and total hip (β=0.142, p=0.001; β=0.087, p=0.032), respectively. Serum uric acid concentration was negatively related to bone turnover markers (OC: r=−0.148, p=0.037; PINP: r=−0.139, p=0005; CTX: r=−0.200, p=0.005). Each unit increase of serum uric acid and total bilirubin was associated with a 0.4% and 5.6% lower risk of osteoporosis or osteopenia (OR=0.996, 95% CI=0.994–0.998; OR=0.944, 95% CI=0.899–0.992), respectively. The risk of osteoporosis and osteopenia in patients with low-tertile concentrations of serum uric acid and total bilirubin was increased (OR=3.486, 95% CI=1.535–7.913).

Conclusions

In men with type 2 diabetes, serum uric acid level and total bilirubin were significantly associated with bone mineral density and were protective factors against osteoporosis and osteopenia.