Alterations in circulating mitochondrial signals at hospital admission for COPD exacerbation.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) exacerbation (ECOPD) alters the natural course of the disease. To date, only C-reactive protein has been used as a biomarker in ECOPD, but it has important limitations. The mitochondria release peptides (Humanin (HN), FGF-21, GDF-15, MOTS-c and Romo1) under certain metabolic conditions. Here, we aimed to evaluate the pathophysiologic, diagnostic and prognostic value of measuring serum mitochondrial peptides at hospital admission in patients with ECOPD. METHODS: A total of 51 consecutive patients admitted to our hospital for ECOPD were included and followed for 1 year; in addition, 160 participants with stable COPD from our out-patient clinic were recruited as controls. RESULTS: Serum FGF-21 (p < .001), MOTS-c (p < .001) and Romo1 (p = .002) levels were lower, and GDF-15 (p < .001) levels were higher, in patients with ECOPD than stable COPD, but no differences were found in HN. In receiver operating characteristic analysis, MOTS-c (AUC 0.744, 95% CI 0.679-0.802, p < .001) and GDF-15 (AUC 0.735, 95% CI 0.670-0.793, p < .001) had the best diagnostic power for ECOPD, with a diagnostic accuracy similar to that of C-RP (AUC 0.796 95% IC 0.735-0.848, p < .001). FGF-21 (AUC 0.700, 95% CI 0.633-0.761, p < .001) and Romo1 (AUC 0.645 95% CI 0.573-0.712, p = .001) had lower diagnostic accuracy. HN levels did not differentiate patients with ECOPD versus stable COPD (p = .557). In Cox regression analysis, HN (HR 2.661, CI95% 1.009-7.016, p = .048) and MOTS-c (HR 3.441, CI95% 1.252-9.297, p = .016) levels exceeding mean levels were independent risk factors for re-admission. CONCLUSIONS: Most mitochondrial peptides are altered in ECOPD, as compared with stable COPD. MOTS-c and GDF15 levels have a diagnostic accuracy similar to C-RP for ECOPD. HN and MOTS-c independently predict future re-hospitalization.

Uncovering genetic causes of hypophosphatemia.

BACKGROUND: Chronic hypophosphatemia can result from a variety of acquired disorders, such as malnutrition, intestinal malabsorption, hyperparathyroidism, vitamin D deficiency, excess alcohol intake, some drugs, or organ transplantation. Genetic disorders can be a cause of persistent hypophosphatemia, although they are less recognized. We aimed to better understand the prevalence of genetic hypophosphatemia in the population. METHODS: By combining retrospective and prospective strategies, we searched the laboratory database of 815,828 phosphorus analyses and included patients 17-55 years old with low serum phosphorus. We reviewed the charts of 1287 outpatients with at least 1 phosphorus result ≤2.2 mg/dL. After ruling out clear secondary causes, 109 patients underwent further clinical and analytical studies. Among them, we confirmed hypophosphatemia in 39 patients. After excluding other evident secondary causes, such as primary hyperparathyroidism and vitamin D deficiency, we performed a molecular analysis in 42 patients by sequencing the exonic and flanking intronic regions of a panel of genes related to rickets or hypophosphatemia (CLCN5, CYP27B1, dentin matrix acidic phosphoprotein 1, ENPP1, FAM20C, FGFR1, FGF23, GNAS, PHEX, SLC34A3, and VDR). RESULTS: We identified 14 index patients with hypophosphatemia and variants in genes related to phosphate metabolism. The phenotype of most patients was mild, but two patients with X-linked hypophosphatemia (XLH) due to novel PHEX mutations had marked skeletal abnormalities. CONCLUSION: Genetic causes should be considered in children, but also in adult patients with hypophosphatemia of unknown origin. Our data are consistent with the conception that XLH is the most common cause of genetic hypophosphatemia with an overt musculoskeletal phenotype.

Circulating levels of mitochondrial oxidative stress-related peptides MOTS-c and Romo1 in stable COPD: A cross-sectional study.

Background: MOTS-c and Romo1 are mitochondrial peptides that are modulated by oxidative stress. No previous studies have explored circulating levels of MOTS-c in patients with chronic obstructive pulmonary disease (COPD). Methods: We enrolled 142 patients with stable COPD and 47 smokers with normal lung function in an observational cross-sectional study. We assessed serum levels of both MOTS-c and Romo1 and associated these findings with clinical characteristics of COPD. Results: Compared with smokers with normal lung function, patients with COPD had lower levels of MOTS-c (p = 0.02) and higher levels of Romo1 (p = 0.01). A multivariate logistic regression analysis revealed that above-median MOTS-c levels were positively associated with Romo1 levels (OR 1.075, 95% CI 1.005-1.150, p = 0.036), but no association was found with other COPD characteristics. Below-median levels of circulating MOTS-c were associated with oxygen desaturation (OR 3.25 95% CI 1.456-8.522, p = 0.005) and walking <350 meters (OR 3.246 95% CI 1.229-8.577, p = 0.018) in six-minute walk test. Above-median levels of Romo1 were positively associated with current smoking (OR 2.756, 95% CI 1.133-6.704, p = 0.025) and negatively associated with baseline oxygen saturation (OR 0.776 95% CI 0.641-0.939, p = 0.009). Conclusions: Reduced levels of circulating MOTS-c and increased levels of Romo1 were detected in patients diagnosed with COPD. Low levels of MOTS-c were associated with oxygen desaturation and poorer exercise capacity using 6 min walk test. Romo1 was associated with current smoking and baseline oxygen saturation. Trial registration: www.clinicaltrials.gov; No.: NCT04449419; URL: www.clinicaltrials.gov. Date of registration: June 26, 2020.

Associations between serum mitokine levels and outcomes in stable COPD: an observational prospective study.

Mitokines (Humanin (HN), GDF15 and FGF21) are produced as a result of mitochondrial dysfunction and may have major roles in chronic inflammation, malnutrition and exercise capacity in people with COPD. Except for GDF15, studies on this subject are lacking. A total of 165 patients with stable COPD and 49 smokers without COPD were enrolled. We assessed their serum mitokine levels and clinical characteristics at baseline. We recorded moderate and severe exacerbation for the next 12 months. Baseline serum HN (p = 0.037) and GDF-15 (p = 0.013) levels were higher in the COPD group. High HN levels were independently associated with a high risk of exacerbation (HRE) (OR 2.798, 95% CI 1.266-6.187, p = 0.011), malnutrition (OR 6.645, 95% CI 1.859-23.749, p = 0.004), and 6MWD (OR 0.995, 95% CI 0.991-0.999, p = 0.008), and future moderate (HR 1.826, 95% CI 1.181-2.822, p = 0.007) and severe exacerbations (HR 3.445, 95% CI 1.357-8.740, p = 0.009). High GDF15 levels were associated with HRE (OR 3.028, 95% CI 1.134-8.083, p = 0.027), 6MWD (OR 0.995, 95% CI 0.990-0.999, p = 0.017) and predicted desaturation in 6MWT (OR 3.999, 95% CI 1.487-10.757, p = 0.006). High FGF21 levels were associated with HRE (OR 2.144, 95% CI 1.000-4.600, p = 0.05), and predicted future severe exacerbation (HR 4.217, 95% CI 1.459-12.193, p = 0.008). The mitokine levels were higher in patients with COPD than smokers without COPD, and were associated with important clinical outcomes such as exercise capacity and COPD exacerbation. Among the mitokines, HN showed the strongest association with COPD and may serve as a future risk biomarker in this disease.Trial registation NCT04449419.

Evolution of Mitochondrially Derived Peptides Humanin and MOTSc, and Changes in Insulin Sensitivity during Early Gestation in Women with and without Gestational Diabetes.

Our purpose is to study the evolution of mitochondrially derived peptides (MDPs) and their relationship with changes in insulin sensitivity from the early stages of pregnancy in a cohort of pregnant women with and without gestational diabetes (GDM). MDPs (humanin and MOTSc) were assessed in the first and second trimesters of gestation in 28 pregnant women with gestational diabetes mellitus (GDM) and a subgroup of 45 pregnant women without GDM matched by BMI, age, previous gestations, and time of sampling. Insulin resistance (IR) was defined as a HOMA-IR index ≥70th percentile. We observed a significant reduction in both humanin and MOTSc levels from the first to the second trimesters of pregnancy. After adjusting for predefined variables, including BMI, statistically nonsignificant associations between lower levels of humanin and the occurrence of a high HOMA-IR index were obtained (adjusted OR = 2.63 and 3.14 for the first and second trimesters, linear p-trend 0.260 and 0.175, respectively). Regarding MOTSc, an association was found only for the second trimester: adjusted OR = 7.68 (95% CI 1.49-39.67), linear p-trend = 0.012. No significant associations were observed in humanin change with insulin resistance throughout pregnancy, but changes in MOTSc levels were significantly associated with HOMA-IR index: adjusted OR 3.73 (95% CI 1.03-13.50). In conclusion, MOTSc levels, especially a strong decrease from the first to second trimester of gestation, may be involved in increasing insulin resistance during early gestation.

High parathyroid hormone predicts exacerbations in COPD patients with hypovitaminosis D.

BACKGROUND: Hypovitaminosis D has been linked to deterioration in clinical parameters and lung function in COPD. As a response to low levels of vitamin D serum Parathyroid Hormone (iPTH) is increased in some, but not all, patients. The aim of this study was to determine whether COPD patients with elevated PTH levels are at higher risk of COPD exacerbations and hospitalizations. METHODS: 166 COPD outpatients were randomly preselected. Clinical and analytical characteristics were assessed at baseline. After excluding patients with other conditions known to disturb calcium metabolism 141 patients were identified. Except one, all patients were prospectively followed for 12 months after obtaining the blood samples. Hypovitaminosis D was considered when serum 25(OH)D < 30 ng/mL. Secondary hyperparathyroidism was considered when serum iPTH was higher than normal (50 pg/mL) in patients with hypovitaminosis D. COPD exacerbations and hospital admissions were recorded during the follow-up. RESULTS: Prevalence of hypovitaminosis D in COPD patients was 89.3%, prevalence of secondary hyperparathyroidism associated with hypovitaminosis D was 22,9%. Cox proportional risk analysis showed that patients belonging to the high iPTH-low 25(OH)D group were at a higher risk of moderate COPD exacerbations (HR 1.81 (CI95% 1.043-3.127), p = 0.035) and hospital admissions (HR 5.45 (CI95% 2.018-14.720), p = 0.002) as compared with those with normal iPTH-low 25(OH)D levels. CONCLUSIONS: COPD patients with hypovitaminosis D and elevated iPTH have higher risk of moderate exacerbations and hospitalizations than those with hypovitaminosis D and normal iPTH.

Measurement and clinical usefulness of bilirubin in liver disease.

Elevated plasma bilirubin levels are a frequent clinical finding. It can be secondary to alterations in any stage of its metabolism: (a) excess bilirubin production (i.e., pathologic hemolysis); (b) impaired liver uptake, with elevation of indirect bilirubin; (c) impaired conjugation, prompted by a defect in the UDP-glucuronosyltransferase; and (d) bile clearance defect, with elevation of direct bilirubin secondary to defects in clearance proteins, or inability of the bile to reach the small bowel through bile ducts. A liver lesion of any cause reduces hepatocyte cell number and may impair the uptake of indirect bilirubin from plasma and diminish direct bilirubin transport and clearance through the bile ducts. Various analytical methods are currently available for measuring bilirubin and its metabolites in serum, urine and feces. Serum bilirubin is determined by (1) diazo transfer reaction, currently, the gold-standard; (2) high-performance liquid chromatography (HPLC); (3) oxidative, enzymatic, and chemical methods; (4) direct spectrophotometry; and (5) transcutaneous methods. Although bilirubin is a well-established marker of liver function, it does not always identify a lesion in this organ. Therefore, for accurate diagnosis, alterations in bilirubin concentrations should be assessed in relation to patient anamnesis, the degree of the alteration, and the pattern of concurrent biochemical alterations.

Cortisol and adrenal androgens as independent predictors of mortality in septic patients.

OBJECTIVE: To determine the prognostic value of cortisol, Dehydroepiandrosterone (DHEA) and Dehydroepiandrosterone-sulfate (DHEAS), together with their ratios (cortisol/DHEA and cortisol/DHEAS), as independent predictors of mortality in septic patients. METHODS: Prospective cohort study of 139 consecutive patients with a diagnosis of severe sepsis or septic shock. Adrenal hormones were determined within the first 24 hours of the septic process. To determine and compare the predictive ability of each marker for the risk of unfavorable evolution (in-hospital, 28-day and 90-day mortality), ROC (Receiver Operating Characteristic) curves were constructed and the area under the curve (AUC) was determined. As measures of association, adjusted odds ratios (OR) with their 95% confidence intervals (95%CI) were estimated by unconditional logistic regression. Cortisol, DHEA and DHEAS results were compared to lactate, CRP, SOFA and APACHE II Scores. RESULTS: Cortisol showed the best predictive ability, with AUCs of 0.758, 0.759 and 0.705 for in-hospital mortality, and 28-day and 90-day mortality, respectively; whereas AUCs for 28 days mortality for SOFA and APACHE II scores, and other biomarkers studied, such as Lactate or CRP, were 0.644, 0.618, 0.643 and 0.647, respectively. Associations between high cortisol levels (>17.5 µg/dL) and mortality were strong and statistically significant for in-hospital and 28-day mortality: adjusted ORs 10.13 and 9.45 respectively, and lower for long term mortality (90 days): adjusted OR 4.26 (95% CI 1.34-13.56), p trend 0.014. Regarding adrenal androgens, only positive associations were obtained for DHEAS and most of these positive associations did not yield statistical significance. Regarding Cortisol/DHEA and cortisol/DHEAS ratios, they did not improve the predictive ability of cortisol. The only exception was the cortisol/DHEAS ratio, which was the best predictor of mortality at 90 days (AUC 0.737), adjusted OR for highest cortisol/DHEAS ratio values 6.33 (95%CI 1.77-22.60), p trend 0.002. CONCLUSION: Basal cortisol measured within the first 24 hours of the septic process was the best prognostic factor for in-hospital and 28-day mortality, even superior to the Sequential Organ Failure Assessment (SOFA) or Acute Physiology and Chronic Health Evaluation II (APACHE II) scores. The cortisol/DHEAS ratio was an independent predictor of long-term mortality.

Vitamin D binding protein, but not vitamin D or vitamin D-related peptides, is associated with septic shock mortality / La proteína transportadora de vitamina D, pero no la vitamina D ni los péptidos derivados de ella se asocia con la mortalidad de los pacientes en shock séptico

BACKGROUND: The aim of this study was to assess the prognostic value of vitamin D, vitamin D binding protein (VDBP) and vitamin D-related peptides in septic shock patients in relation to hospital mortality. METHODS: This is a single-center, prospective, observational study that included all consecutive patients meeting criteria for septic shock who were admitted to the ICU. VDBP, 25-hydroxy vitamin D, 1,25-dihydroxy vitamin D, cathelicidin and beta-defensin levels were determined in blood samples obtained on admission to the ICU. RESULTS: Seventy-five patients were studied. The best area under the curve (AUC) for prediction of in-hospital mortality was for VDBP (0.78), with a negative predictive value of 85.45% for the optimal cut-off point. VDBP was also the only variable that had a statistically significant association with a higher risk of in-hospital mortality, regardless of other assessed variables and pre-determined confounders: adjusted odds ratio of 5.20 (95% confidence interval: 1.21-22.36). When restricted to patients with vitamin D insufficiency (n = 54), the AUC was 0.77, and the adjusted OR 12.22 (95% CI: 1.46-102.14; p = 0.021) for in-hospital mortality. CONCLUSIONS: VDBP levels showed a statistically significant association with in-hospital mortality, supporting the clinical utility of VDBP as a good prognostic marker in septic shock patients. Vitamin D and vitamin D-related peptides are not associated with in-hospital mortality. These results should be confirmed in a multicentre study with a larger sample size

INTRODUCCIÓN: El objeto de este estudio fue evaluar el valor pronóstico de la vitamina D, la proteína transportadora de la vitamina D (PTVD) y de los péptidos derivados de la vitamina D en relación a la mortalidad hospitalaria de los pacientes en shock séptico. MÉTODOS: Se trata de un estudio prospectivo unicéntrico observacional que incluyo consecutivamente a todos los pacientes que ingresan en la UCI en shock séptico. Los valores de la PTVD, 25-hydroxy vitamina D, 1,25-dihydroxy vitamina D, catelicidina y beta-defensina se cuantificaron en muestras sanguíneas extraídas en el momento del ingreso en la UCI. RESULTADOS: Se incluyeron un total de 75 pacientes. La mejor área bajo la curva (AUC) para la predicción de mortalidad hospitalaria fue para la PTVD (0,78), con un valor predictivo negativo del 85,45% para el punto de corte óptimo. La PTVD fue además la única variable asociada estadísticamente con un mayor riesgo de mortalidad hospitalaria independientemente de las otras variables evaluadas y de los factores de confusión prestablecidos: odds ratio ajustada 5,20 (intervalo de confianza [IC] 95%: 1,21-22,36). Cuando el estudio se focalizó en los pacientes con insuficiencia de vitamina D (N = 54), el AUC fue de 0,77 y la odds ratio ajustada de 12,22 (IC 95%: 1,46-102,14; p = 0,021) en relación a la mortalidad hospitalaria. CONCLUSIONES: Los valores sanguíneos de la PTVD se asociaron de forma estadísticamente significativa con la mortalidad hospitalaria, apoyando la potencial utilidad clínica de la PTVD como un buen marcador pronóstico en los pacientes en shock séptico. La vitamina D y los péptidos derivados de ella no relacionaron con la mortalidad hospitalaria. Estos resultados deben ser confirmados en un estudio multicéntrico con mayor número de pacientes

Vitamin D binding protein, but not vitamin D or vitamin D-related peptides, is associated with septic shock mortality.

BACKGROUND: The aim of this study was to assess the prognostic value of vitamin D, vitamin D binding protein (VDBP) and vitamin D-related peptides in septic shock patients in relation to hospital mortality. METHODS: This is a single-center, prospective, observational study that included all consecutive patients meeting criteria for septic shock who were admitted to the ICU. VDBP, 25-hydroxy vitamin D, 1,25-dihydroxy vitamin D, cathelicidin and beta-defensin levels were determined in blood samples obtained on admission to the ICU. RESULTS: Seventy-five patients were studied. The best area under the curve (AUC) for prediction of in-hospital mortality was for VDBP (0.78), with a negative predictive value of 85.45% for the optimal cut-off point. VDBP was also the only variable that had a statistically significant association with a higher risk of in-hospital mortality, regardless of other assessed variables and pre-determined confounders: adjusted odds ratio of 5.20 (95% confidence interval: 1.21-22.36). When restricted to patients with vitamin D insufficiency (n=54), the AUC was 0.77, and the adjusted OR 12.22 (95% CI: 1.46-102.14; p=0.021) for in-hospital mortality. CONCLUSIONS: VDBP levels showed a statistically significant association with in-hospital mortality, supporting the clinical utility of VDBP as a good prognostic marker in septic shock patients. Vitamin D and vitamin D-related peptides are not associated with in-hospital mortality. These results should be confirmed in a multicentre study with a larger sample size.

The Ratio Serum Creatinine/Serum Cystatin C (a Surrogate Marker of Muscle Mass) as a Predictor of Hospitalization in Chronic Obstructive Pulmonary Disease Outpatients.

BACKGROUND: In chronic obstructive pulmonary disease (COPD), low muscle mass has been associated with several clinical outcomes such as low exercise capacity, hospital admission, and mortality. The Sarcopenia Index (SI) is a novel way to estimate muscle mass based on the ratio of serum creatinine (produced exclusively by muscle)/cystatin C (produced by all nucleated body cells). OBJECTIVES: This study aims to assess the SI in stable COPD outpatients, as compared with a healthy control group, to quantify its relationship with several important clinical features in COPD, and to study its potential usefulness to predict COPD exacerbations and hospital admissions. METHODS: The SI was calculated in 18 healthy control subjects and 65 stable COPD outpatients were included in the study. Patients were prospectively followed for 1 year after being enrolled in the study. RESULTS: COPD patients had a lower SI than controls, that is lower muscle mass. Furthermore, patients with a modified Medical Research Council dyspnea score ≥2, patients with a COPD Assessment Test score ≥10, and patients with a high risk of exacerbation had lower levels of SI compared with patients without these characteristics. SI correlated with FEV1 (r = 0.491, p < 0.001), the 6-min walking test (r = 0.560, p = 0.001), and the Fat-Free Mass Index (r = 0.431, p = 0.017). Univariate and multivariate Cox proportional risk analysis showed that a low SI is an independent predictor of hospital admission in COPD outpatients followed for 1 year (HR 5.16, p = 0.025). CONCLUSIONS: The ratio serum creatinine/serum cystatin C correlates with several COPD characteristics, and it can be used to predict COPD hospitalization.

"Single nucleotide polymorphisms of the OPG/RANKL system genes in primary hyperparathyroidism and their relationship with bone mineral density".

BACKGROUND: Primary hyperparathyroidism (PHPT) affects mainly cortical bone. It is thought that parathyroid hormone (PTH) indirectly regulates the activity of osteoclasts by means of the osteoprotegerin/ligand of the receptor activator of nuclear factor-κß (OPG/RANKL) system. Several studies have confirmed that OPG (osteoprotegerin) and RANKL (ligand of the receptor activator of nuclear factor-κß) loci are determinants of bone mineral density (BMD) in the general population. The aim of this study is to analyze the relationship between fractures and BMD and the rs3102735 (163 A/G), rs3134070 (245 T/G) and rs2073618 (1181 G/C) SNPs of the OPG and the rs2277438 SNP of the RANKL, in patients with sporadic PHPT. METHODS: We enrolled 298 Caucasian patients with PHPT and 328 healthy volunteers in a cross-sectional study. We analyzed anthropometric data, history of fractures or renal lithiasis, biochemical determinants including markers for bone remodelling, BMD measurements in the lumbar spine, total hip, femoral neck and distal radius, and genotyping for the SNPs to be studied. RESULTS: Regarding the age of diagnosis, BMI, menopause status, frequency of fractures or renal lithiasis, we found no differences between genotypes in any of the SNPs studied in the PHPT group. Significant lower BMD in the distal radius with similar PTH levels was found in the minor allele homozygotes (GG) compared to heterozygotes and major allele homozygotes in both OPG rs3102735 (163 A/G) and OPG rs3134070 (245 T/G) SNPs in those with PHPT compared to control subjects. We found no differences between genotypes of the OPG rs2073618 (1181 G/C) SNP with regard to BMD in the PHPT subjects. In the evaluation of rs2277438 SNP of the RANKL in PHPT patients, we found a non significant trend towards lower BMD in the 1/3 distal radius and at total hip in the minor allele homocygotes (GG) genotype group versus heterocygotes and major allele homocygotes (AA). CONCLUSIONS: Our study provides the first evaluation of the relationship between SNPs of the OPG/RANK system and sporadic PHPT. Subjects with PHPT and minor homocygote genotype (GG) for the OPG rs3102735 (163 A/G) and OPG rs3134070 (245 T/G) SNPs have lower BMD in the distal radius, and this association does not appear to be mediated by differences in PTH serum levels.