Beyond brain injury biomarkers: chemoattractants and circulating progenitor cells as biomarkers of endogenous rehabilitation effort in preterm neonates with encephalopathy

Introduction

Preclinical work and studies in adults have shown that endogenous regeneration efforts that involve mobilization of progenitor cells take place after brain injury. However, kinetics of endogenous circulating progenitor cells (CPCs) in preterm neonates is not well described, particularly their possible role regarding brain injury and regeneration. We aimed to assess the kinetics of CPCs in neonates with encephalopathy of prematurity in relation to brain injury biomarkers, chemoattractants and relevant antenatal and postanal clinical factors, in an effort to outline the related pathophysiology.

Materials and methods

47 preterm neonates (of 28-33 weeks GA) were enrolled: 31 newborns with no or minimal brain injury (grade I IVH) and 16 prematures with encephalopathy (grade III or IV IVH, PVL or infarct). Peripheral blood samples obtained on days 1, 3, 9, 18 and 45 after birth were analyzed using flow cytometry, focusing on EPCs (early and late Endothelial Progenitor Cells), HSCs (Hematopoietic Stem Cells) and VSELs (Very Small Embryonic-Like Stem Cells). At the same time-points serum levels of S100B, Neuron-specific Enolase (NSE), Erythropoietin (EPO), Insulin-like growth factor-1 (IGF-1) and SDF-1 were also measured. Neonates were assessed postnatally with brain MRI, and with Bayley III developmental test at 2 years of corrected age.

Results

Preterms with brain injury proved to have significant increase of S100B and NSE, followed by increase of EPO and enhanced mobilization mainly of HSCs, eEPCs and lEPCs. IGF-1 was rather decreased in this group of neonates. IGF-1 and most CPCs were intense decreased in cases of antenatal or postnatal inflammation. S100B and NSE correlated with neuroimaging and language scale in Bayley III test, providing good prognostic ability.

Conclusion

The observed pattern of CPCs' mobilization and its association with neurotrophic factors following preterm brain injury indicate the existence of an endogenous brain regeneration process. Kinetics of different biomarkers and associations with clinical factors contribute to the understanding of the related pathophysiology and might help to early discriminate neonates with adverse outcome. Timely appropriate enhancement of the endogenous regeneration effort, when it is suppressed and insufficient, using neurotrophic factors and exogenous progenitor cells might be a powerful therapeutic strategy in the future to restore brain damage and improve the neurodevelopmental outcome in premature infants with brain injury.

Mobilization of circulating progenitor cells following brain injury in premature neonates could be indicative of an endogenous repair process. A pilot study

BACKGROUND

Preclinical data and adult studies have showed an endogenous regeneration process following brain damage that involves mobilization of progenitor cells. This process is not well described in preterm neonates. The present study aims to investigate the mobilization of Circulating Progenitor Cells (CPCs) and their relation to biomarkers of brain injury in preterm neonates.

METHODS

This is a prospective cohort study of preterm infants with gestational age (GA) <34 weeks. Serial cranial ultrasounds scans were performed in all neonates. Brain injury was defined by the presence of intraventricular hemorrhage grade III/IV, cystic periventricular leukomalacia or infarct. Peripheral blood samples were collected from all neonates on days(d) 1, 3, 9, 18 and 45 of life for the measurement of levels of CPCs [early and late Endothelial Progenitor Cells (EPCs), Haematopoietic Stem Cells (HSCs) and Very Small Embryonic-Like Stem Cells (VSELs)], Neuron-Specific Enolase (NSE), S100b, Erythropoietin (EPO) and Stromal Cell-Derived Factor-1 (SDF-1) .

RESULTS

Ten out of the 23 preterm infants included in the study developed brain injury; the remaining thirteen infants served as controls. In the brain injury group a significant increase of HSCs (d9, d45), early EPCs (d3, d9, d18) and late EPCs (d1, d3, d9, d18, d45) was observed compared to controls. VSELs on d45 were significantly higher in controls. S100b on d1, EPO on d1, SDF-1 on d3 and NSE on d18 were significantly increased in the brain injury group. Moreover, CPCs were significantly related to S100b, NSE, EPO and SDF-1 levels at multiple time points.

CONCLUSIONS

The observed pattern of CPCs mobilization and its association with biomarkers following brain injury in preterm neonates indicate the existence of an endogenous brain regeneration process. Enhancement of this process with exogenous progenitor cell transplantation might be a powerful therapeutic strategy to restore brain damage and improve the neurodevelopmental outcome in premature infants. Hippokratia 2015; 19 (2):141-147.

The effect of L-thyroxine substitution on lipid profile, glucose homeostasis, inflammation and coagulation in patients with subclinical hypothyroidism

AIMS

Subclinical hypothyroidism (SH) is associated with increased risk for atherosclerosis, mainly attributable to dyslipidaemia and hypercoagulability. However, conflicting data exist regarding the effect of L-thyroxine substitution on these parameters. The purpose of this study was to assess the effect of L-thyroxine therapy on lipidaemic profile, coagulation markers, high-sensitivity C-reactive protein (hsCRP) and glucose homoeostasis in SH patients.

METHODS

It was a prospective open-label study. The following parameters were measured before and 6 months after intervention: anthropometric data, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), apolipoproteins B (apoB) and A1 (apoA1), lipoprotein (a) [Lp(a)], fasting plasma glucose and insulin, homoeostasis model assessment-insulin resistance (HOMA-IR), hsCRP, antithrombin III (AT-III), protein C (PC), protein S (PS), fibrinogen and homocysteine.

RESULTS

Thirty-two patients (30 women) aged 52.1 ± 13.9 years with SH completed the study. Baseline mean TSH levels were 6.79 ± 2.58 mIU/ml. Achievement of euthyroidism significantly reduced systolic blood pressure (BP) in patients with SH (from 135.2 ± 18.5 to 129.7 ± 15.8 mmHg, p = 0.03) and diastolic BP only in those with baseline TSH levels > 7 mIU/ml (from 79.5 ± 9.8 to 72.1 ± 7.3 mmHg, p = 0.03). No significant changes in body weight, TC, LDL-C, HDL-C, TG, apoB, glucose, insulin, HOMA-IR, hsCRP, AT-III, PC, PS, fibrinogen or homocysteine levels were noticed after restoration of euthyroidism, except for a decrease in apoA1 (p = 0.04) and an increase in Lp(a) levels (p = 0.02).

CONCLUSIONS

Except for a reduction in systolic and diastolic BP, thyroid substitution therapy does not affect lipidaemic profile, systematic inflammation, glucose homoeostasis or coagulation in patients with SH.

Clonidine and glucagon stimulation for testing growth hormone secretion in children and adolescents: can we make it with fewer samples?

BACKGROUND

Our aim was to retrospectively evaluate the possibility to reduce the number of GH analyses during clonidine and glucagon tests without compromising accuracy.

SUBJECTS AND METHODS

Two hundred and forty-five tests were performed in a total of 188 children and adolescents with a mean age of 9.93 ± 2.88 yr in a single center during the last 5 yr.

RESULTS

Ninety-one out of 158 (57.59%) clonidine tests and 47/87 (54.02%) glucagon tests had at least one sample >10 μg/l (negative). For clonidine tests, not measuring GH at 30 min would have resulted in only one negative test missed (0.63% false positive result), whereas not measuring GH both at 0 and 30 min would have increased the false positive percentage to 2.53%. Ending clonidine tests at 90 min would have resulted in 7 negative tests missed (4.43% false positive results). For glucagon tests, more than half of the tests peaked at 120 min (56.32%). Skipping sampling at 0, 60 and 180 min provided a false positive rate of 5.75%.

CONCLUSIONS

For clonidine tests we can omit blood sampling at time points 0 and 30 min without significantly compromising accuracy.

Acromegaly: presentation, morbidity and treatment outcomes at a single centre

OBJECTIVE

Analysis of patients with acromegaly followed-up at a single centre, focusing on baseline characteristics, morbidity and efficacy of treatment.

DESIGN AND METHODS

Retrospective review of electronic medical records of acromegalics from 1987 to 2009.

RESULTS

One hundred and fifteen patients (45 men), aged 47 ± 14 years, with a mean follow-up of 8.8 ± 0.8 years were studied. Twenty-five per cent had micro- and 75% macroadenomas. Forty-three per cent presented with visual field defects, 49% had hypertension, 25% diabetes mellitus and 35% dyslipidaemia. At follow-up, 50% had myocardial hypertrophy, 55% colon polypodiasis, 74% nodular thyroid disease and 18% adrenal masses. Surgery was performed in 79% (8% twice), followed by conventional radiotherapy in 27%. Fifty-two per cent of the patients achieved remission. Disease control was reported in 65% of microadenomas and 41% of macroadenomas. Remission rates with surgery alone were 41%. Improvement of remission rates was achieved with subsequent treatment with somatostatin analogues (SSA) (53%), or conventional radiotherapy (63%). Nevertheless, pituitary reserve was compromised with the latter. SSA significantly improved outcomes in microadenomas, even as a monotherapy (remission in 89%), in contrast to macroadenomas (0%), although these agents were associated with impaired glucose metabolism and cholelithiasis in half of the patients.

CONCLUSIONS

Acromegaly is associated with an increased morbidity. About half of the treated patients achieved remission (2/3 of microadenomas). The best outcomes were reported for the combination of surgery with radiotherapy, in spite of a higher risk of hypopituitarism. SSA led to remission in a significant percentage of microadenomas, but was associated with increased rates of cholelithiasis and impaired glucose homeostasis.

Comparative effects of rosuvastatin and atorvastatin on glucose metabolism and adipokine levels in non-diabetic patients with dyslipidaemia: a prospective randomised open-label study

AIMS

The impact of statins on glucose metabolism and adipokines remains controversial. We compared the effects of rosuvastatin and atorvastatin on glucose homeostasis, insulin sensitivity (IS), adiponectin and leptin levels as well as systemic inflammation in non-diabetic patients with dyslipidaemia.

METHODS

Thirty-six patients were randomly assigned to 10 mg/day of rosuvastatin (n = 18) or 20 mg/day of atorvastatin (n = 18) for 12 weeks. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, triglycerides (TG), fasting plasma glucose, insulin, homeostasis model assessment-insulin resistance (HOMA-IR), quantitative IS check index (QUICKI), adiponectin, leptin and high-sensitivity C-reactive protein (hsCRP) were measured at baseline and after 4 and 12 weeks.

RESULTS

Both statins significantly lowered TC, LDL-C, non-HDL-C and TG compared with baseline. Only rosuvastatin caused a significant reduction in insulin and HOMA-IR levels (-35%, p = 0.005 and -33%, p = 0.011 respectively) and a significant increase in QUICKI (+11%, p = 0.003) at 12 weeks. In terms of adipokines and hsCRP, no difference was observed after 4 and 12 weeks of treatment with either statin.

CONCLUSIONS

Rosuvastatin compared with atorvastatin resulted in significant improvements in IS indices. No significant changes in adiponectin, leptin or hsCRP levels were observed at 4 and 12 weeks of treatment with either statin.

Effect of exogenous intermittent recombinant human PTH 1-34 administration and chronic endogenous parathyroid hormone excess on glucose homeostasis and insulin sensitivity

We aimed to evaluate the effects of exogenous intermittent teriparatide (rhPTH 1-34) administration versus the chronic exposure to excess endogenous parathyroid hormone (PTH), as in pHPT, on glucose homeostasis. Two patient groups were studied: Group 1 included 25 normocalcemic women with postmenopausal osteoporosis (age 65.2+/-1.6 years) studied before and six months after teriparatide initiation; Group 2 included 19 postmenopausal women with pHPT (age 55.2+/-2.5 years) studied before and six months after successful parathyroidectomy. Calcium - total (Ca) and corrected (CCa) - ALP, PTH, as well as glucose and insulin concentrations during an oral glucose tolerance test (OGTT) were determined before and six months after either intervention. Area under the curve for glucose (AUCglu) and insulin (AUCins) were calculated. DeltaIns30'/DeltaGlu30' was applied as an index of insulin secretion. The HOmeostasis Model of Assessment (HOMA) and Matsuda ISI (Insulin Sensitivity Index) were used to calculate insulin resistance (IR) and whole body insulin sensitivity, respectively. In Group 1 no difference was found in any OGTT-derived parameter. In Group 2 significant reductions in AUCins and DeltaIns30'/DeltaGlu30' were observed. No correlation between the change in DeltaCCa or DeltaPTH and DeltaAUCglu or DeltaAUCins was found in either group. Our data suggest that while subtle transient alterations of Ca and PTH within the normal range as in exogenous rhPTH 1-34 administration do not affect glucose homeostasis, the continuously elevated Ca and endogenous PTH levels as in pHPT affect insulin sensitivity and result in increased insulin secretion.

Acute and chronic effect of teriparatide on glucose metabolism in women with established osteoporosis

There is indirect evidence of unfavorable effects of parathyroid hormone (PTH) on glucose metabolism. Teriparatide (recombinant human PTH 1-34-TPTD) has recently been available for the treatment of osteoporosis. The aim of this prospective study was to evaluate the acute and chronic effect of TPTD on blood glucose and insulin levels in women with established osteoporosis. Twenty-three postmenopausal women with established osteoporosis (mean age 65.6+/-1.8 years) received daily injections of 20 mg TPTD for six months. Three oral glucose tolerance tests (OGTT) were performed: one day before the first injection (OGTT-basal), one hour after (OGTT-acute) and six months after initiation of therapy (OGTT-chronic). There were significant differences between the OGTT-basal and OGTT-acute values in glucose at 90 min (168.3+/-9.8 vs. 180.6+/-9.2, p<0.05) and 120 min (152.0+/-8.7 vs. 170.5+/-7.8, p<0.01), between the OGTT-basal and OGTT-chronic values for glucose at 90 min (168.3+/-9.8 vs. 184.5+/-13.3, p<0.05) and between the OGTT-basal and OGTT-acute for insulin at 90 min (56.7+/-7.4 vs. 68.7+/-8.2, p<0.01). These differences remained significant for the subgroup of patients with normal (n=8) but not impaired glucose tolerance or diabetes mellitus (n=15). TPTD seems to have an acute, subclinical adverse impact on stimulated glucose levels, possibly due to insulin resistance. This impact tends to subside when TPTD is continued on a chronic basis.

Predominance of a methicillin-resistant Staphylococcus aureus clone susceptible to erythromycin and several other non-beta-lactam antibiotics in a Greek hospital

A clone of heterogeneously methicillin-resistant Staphylococcus aureus (MRSA) isolates susceptible to erythromycin, ciprofloxacin, clindamycin, co-trimoxazole, nitrofurantoin, rifampicin, tetracycline and vancomycin, predominated in a Greek hospital with a high incidence of MRSA, representing 69.1% of the total MRSA isolates. All isolates of this clone lacked the conserved genes ermA and aadD. Two subtypes of this clone were detected, the more common being resistant to aminoglycosides and carrying the bi-functional gene aacA-aphD, while an aminoglycoside-susceptible variant, lacking this gene, lost a larger SmaI macrorestriction DNA fragment and gained a smaller fragment.

Nosocomial spread of an unusual methicillin-resistant Staphylococcus aureus clone that is sensitive to all non-beta-lactam antibiotics, including tobramycin

Between January and December 1999, in Hippokration General Hospital, Thessaloniki, Greece, a large proportion of the methicillin-resistant Staphylococcus aureus isolates (34.4%) exhibited susceptibility to virtually all alternative non-beta-lactam antibiotics, including tobramycin. Twenty-five of them were selected randomly for further testing; all belonged to a unique genotype and were characterized as heterogeneously resistant to oxacillin. The aadD gene, encoding tobramycin resistance, failed to be amplified in all cases, indicating absence of the gene or the entire plasmid pUB110 from the mec DNA.

Procalcitonin: does it play a role in male reproduction?

OBJECTIVE

To investigate the presence or absence of procalcitonin in the seminal plasma of both normal and subfertile men.

DESIGN

Controlled clinical study.

SETTING

Academic research environment.

PATIENT(S)

Healthy male volunteers and subfertile men with varicocele or infection of the male accessory glands.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Seminal plasma procalcitonin determinations.

RESULT(S)

Seminal plasma procalcitonin levels from subfertile men were not significantly different from those found in healthy volunteers.

CONCLUSION(S)

Although procalcitonin can be detected in the seminal plasma, these preliminary results indicate that it cannot be used as a diagnostic marker.