正しい方法がわかる臨床基本手技 : from the New England journal of medicine

Haptoglobin: From hemoglobin scavenging to human health

SETTING
A rural Zimbabwean hospital and the surrounding community.


OBJECTIVES
To determine whether a particular haptoglobin phenotype is associated with increased susceptibility to clinical pulmonary tuberculosis, and to determine the outcome of treatment for pulmonary tuberculosis according to haptoglobin phenotype.


DESIGN
A case-control study, and a prospective cohort study.


RESULTS
We studied 98 consecutive patients with sputum-positive pulmonary tuberculosis and 98 sex- and age-matched controls. The haptoglobin (Hp) phenotype distributions did not differ significantly between the tuberculosis patients and controls (P = 0.5). During the 18-month follow-up period after the start of tuberculosis treatment, 6/18 (33%) cases with Hp 2-2 phenotype died compared to 9/47 (19%) with Hp 2-1 and 3/31 (10%) with Hp 1-1. In a logistic regression model, the odds of dying were 6.1-fold greater with Hp 2-2 than with Hp 1-1 (95%CI 1.04-35.1, P = 0.04).


CONCLUSION
Our results suggest that there is equal susceptibility to clinical pulmonary tuberculosis disease amongst different haptoglobin phenotypes. Nonetheless, tuberculosis patients with Hp 2-2 phenotype had a higher risk of mortality.

Haptoglobin polymorphism and mortality in patients with tuberculosis

Skeletal muscle dysfunction and reduced physical capacity are characteristic features of chronic obstructive pulmonary disease (COPD). However, the search for a reliable biomarker to assess muscle health in CODP remains elusive. We analyzed the course of hand-grip strength (HGS) and appendicular skeletal mass index (ASMI) in COPD in relation to spirometry decline and plasma extracellular heat shock protein-72 (eHSP72) and c-terminal fragment of agrin-22 (CAF22) levels. We evaluated male, 62–73 years old patients of COPD (N = 265) and healthy controls (N = 252) at baseline and after 12 and 24 months for plasma biomarkers, spirometry and HGS measurements. HGS declined significantly over time and plasma CAF22, but not eHSP72 levels, had a significant negative association with HGS and ASMI in COPD. Plasma CAF22 also had an association with walking speed and daily steps count in advanced COPD. Lower ASMI was associated with reduced HGS at all time-point. Narrow age-span of the study cohort and exclusion of lower-limb muscles from the analysis are limitations of this study. Taken together, we report that the plasma CAF22 may be a useful tool to assess muscle weakness and atrophy in COPD patients.

Plasma CAF22 Levels as a Useful Predictor of Muscle Health in Patients with Chronic Obstructive Pulmonary Disease

Haptoglobin (Hp) is a glycoprotein that binds free hemoglobin (Hb) in plasma and plays a critical role in tissue protection and prevention of oxidative damage. Besides, it has some regulatory functions. Haptoglobin is an acute-phase protein, its concentration in plasma changes in pathology, and the test for its concentration is part of normal clinical practice. Haptoglobin is a conservative protein synthesized mainly in the liver and lungs and is the subject of research as a potential biomarker of many diseases, including various forms of malignant neoplasms. Haptoglobin has several unique biophysical characteristics. The human Нр gene is polymorphic, has three structural alleles that control the synthesis of three major phenotypes of haptoglobin: homozygous Нр1-1 and Нр2-2, and heterozygous Нр2-1, determined by a combination of allelic variants that are inherited. Numerous studies indicate that the phenotype of haptoglobin can be used to judge the individual predisposition of a person to various diseases. In addition, Hp undergoes various post-translational modifications (PTMs). These are structural transformations (removal of the signal peptide, cutting off the Pre-Hp precursor molecule into two subunits, α and β, limited proteolysis of α-chains, formation of disulfide bonds, multimerization), as well as chemical modifications of α-chains and glycosylation of the β-chain. Glycosylation of the β-chain of haptoglobin at four Asn sites is the most important variable PTM that regulates the structure and function of the glycoprotein. The study of modified oligosaccharides of the β-chain of Hp has become the main direction in the study of pathological processes, including malignant neoplasms. These characteristics indicate the possibility of the existence of Hp in the form of a multitude of proteoforms, probably performing different functions. This review is devoted to the description of the structural and functional diversity and the potential use of Hp as a biomarker of various pathologies.

/pdf/haptoglobin-as-a-biomarker-2np6j10hxo.pdf

Haptoglobin as a Biomarker.

Chronic obstructive pulmonary disease (COPD) is caused by chronic inflammation. Many inflammatory mediators induce the low grade systemic inflammation of COPD. Haptoglobin (Hp) is synthesized in the liver and by lung epithelial and alveolar macrophage cells. However, associations of the serum concentration and phenotype of Hp with COPD are unclear. Therefore, we explored the association of the Hp concentration and Hp phenotype with the inflammatory response and COPD disease severity. We included healthy subjects and COPD patients. The Hp phenotype was categorized by SDS native-PAGE, and concentrations were determined by ELISA. In this trial Hp concentrations in COPD groups were significantly higher than those in healthy controls. There was a significant negative correlation between the Hp concentration and FEV1(%) (p < 0.001), while IL-6 and 8-isoprostane were positively correlated with the Hp concentration. As to the Hp phenotype, there were significant negative correlations between the FEV1 and both Hp2-1 and Hp2-2; IL-6 and 8-isoprostane were significantly positively correlated with Hp2-1 and Hp2-2. The ROC curve analysis of the Hp concentration was significantly higher than CRP. Hp concentrations and phenotype were positively correlated with the severity of COPD, especially Hp2-2. In the future, Hp can be considered a novel biomarker for identifying COPD.

/pdf/relationships-of-haptoglobin-phenotypes-with-systemic-3574kv20qy.pdf

Relationships of Haptoglobin Phenotypes with Systemic Inflammation and the Severity of Chronic Obstructive Pulmonary Disease

Pathological placental inflammation increases the risk for several adult disorders, but these mediators are also expressed under homeostatic conditions, where their contribution to adult health outcomes is unknown. Here we define an expression signature of homeostatic inflammation in the term placenta and use expression quantitative trait loci (eQTLs) to create a polygenic score (PGS) predictive of its expression. Using this PGS in the UK Biobank we carried out a phenome-wide association study, followed by mendelian randomization and identified protective, sex-dependent effects of the placental module on cardiovascular and depressive outcomes. Genes differentially regulated by intra-amniotic infection and preterm birth were also over-represented within the module. Our data support a model where disruption of placental homeostatic inflammation, following preterm birth or intra-amniotic infection, contributes to the increased risk of depression and cardiovascular disease observed in these individuals. Finally, we identify aspirin as a putative modulator of this homeostatic inflammatory signature.

/pdf/homeostatic-inflammation-in-the-placenta-is-protective-28g6rclo.pdf

Pao-Lin Lee

Papers

Relationships of Haptoglobin Phenotypes with Systemic Inflammation and the Severity of Chronic Obstructive Pulmonary Disease

Homeostatic inflammation in the placenta is protective against adult cardiovascular and depressive outcomes