The hypothalamic-pituitary-adrenal and -thyroid axes activation lasting one year after an earthquake swarm: results from a big data analysis.

PURPOSE: To cope physical and/or psychological threats, the human body activates multiple processes, mediated by a close interconnection among brain, endocrine and inflammatory systems. The aim of the study was to assess the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid (HPT) axes involvement after an acute stressful event (Emilia Romagna earthquake swarm) with a big data approach. METHODS: A retrospective, observational trial was performed, collecting all biochemical examinations regarding HPA and HPT axes performed in the same laboratory the year before and the year after the earthquake swarm (20-29 May 2012). RESULTS: Comparing 2576 pre-earthquake to 3021 post-earthquake measurements, a cortisol serum level increase was observed (p < 0.001). Similar increase was evident for urinary free cortisol (p = 0.016), but not for adrenocorticotropic hormone (p = 0.222). The biochemical hypercortisolism incidence increased from 7.6 to 10.3% after earthquakes (p = 0.001). Comparing 68,456 pre-earthquake to 116,521 post-earthquake measurements, a reduction in thyroid-stimulating hormone (TSH) levels was evident (p = 0.018), together with an increase in free triiodothyronine and free thyroxine levels (p < 0.001 and p < 0.001). Moreover, a significant increase in altered TSH after earthquakes was registered considering the epicenter-nearest measurements (p < 0.001). No clinically relevant alterations were observed considering thyroid-specific autoantibodies. CONCLUSION: A long-term HPA axis activation in the inhabitants of the earthquake-affected areas was highlighted for the first time. Moreover, an increased incidence of biochemical hypercortisolism emerged after earthquakes. We confirmed a recruitment of HPT axis after stressful events, together with increased incidence of altered TSH in the. Our big data study allowed to increase knowledge about the connection between external stressors and endocrine regulation.

Cerebrospinal fluid kappa and lambda free light chains in oligoclonal band-negative patients with suspected multiple sclerosis.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) kappa free light chains (FLCs) may be a more sensitive marker of intrathecal immunoglobulin (Ig)G synthesis compared with oligoclonal bands (OCBs). Our aim was to retrospectively determine the additional value of the kappa and lambda index (CSF FLC/serum FLC)/(CSF albumin/serum albumin) in predicting a multiple sclerosis (MS) diagnosis in a group of OCB-negative patients with suspected MS. METHODS: The CSF and serum kappa and lambda FLCs were tested using the Freelite kit (serum) and Freelite Mx (CSF) assay (The Binding Site Group, Bimingham, UK) in 391 OCB-negative patients with suspected/possible MS and in 54 OCB-positive patients with MS. RESULTS: The CSF kappa FLC levels were below the detection limit (0.27 mg/L) in 61% of patients. Using quantitative data, we found the best kappa index cut-off value for the prediction of MS to be 5.8. A kappa index ≥5.8 was present in 25% of OCB-negative MS (23/92) and in 98% of OCB-positive patients with MS. Using a qualitative approach and a kappa index cut-off of 5.9, based on literature data, we likewise found that 24% of OCB-negative patients with MS had a kappa index ≥5.9, compared with 5.4% of OCB-negative patients without MS (P < 0.001). No reliable data could be obtained for the lambda index; lambda FLCs were below the detection limit (0.68 mg/L) in 90% of CSF samples. CONCLUSIONS: The kappa index could contribute to the identification of OCB-negative patients with a high probability of an MS diagnosis. Using more sensitive techniques might even improve the diagnostic performance of the kappa index and better define the role of the lambda index.

Reliability of calcium-phosphorus (Ca/P) ratio as a new, accurate and inexpensive tool in the diagnosis of some Ca-P disorders.

PURPOSE: The serum calcium/phosphorus (Ca/P) ratio is an accurate tool to differentiate patients with primary hyperparathyroidism (PHPT) from healthy subjects. However, other disorders of the Ca-P metabolism might impair the Ca/P ratio, such as hypophosphatemia (HypoP) not PHPT related. The aim of this study is to examine the diagnostic value of Ca/P ratio in the diagnosis of PHPT and HypoP not PHPT related. METHODS: Single-center, retrospective, case-control study, including 150 patients with PHPT and 306 patients with HypoP, compared with 150 controls. HypoP patients were enrolled among HIV-infected patients by selecting those with Fanconi-like syndrome due to antiretroviral treatment. Parameters which were measured were serum Ca, P, parathyroid hormone (PTH), 25-OH vitamin D, albumin and creatinine). RESULTS: The Ca/P ratio was significantly higher in PHPT and HypoP patients, compared to controls (p < 0.0001). At receiver operator characteristic (ROC) curve analysis, the cut-off of 3.56 (2.75 SI) for Ca/P ratio was able to identify patients with PHPT and HypoP (sensitivity 95%; specificity 93%). Among patients with Ca/P ratio above 3.56, the thresholds of 10.3 mg/dL (2.6 mmol/L) for serum Ca (sensitivity 93%; specificity 98%) and 80.5 pg/mL for PTH (sensitivity 91%; specificity 91%) were defined for the specific diagnosis of PHPT. CONCLUSIONS: The Ca/P ratio above 3.56 (2.75 SI) is a highly accurate tool to identify PHPT and HypoP not PHPT-related patients. Thanks to its simplicity, this index can be proposed as a screening and first-line examination in the diagnostic work-up when a disorder of Ca-P metabolism is suspected or should be ruled out.

Dietary supplements, drugs and doping in the sport society.

Consumption of supplements and the use/abuse of drugs to support athletic performance is increasingly growing. The aim of this paper is to approach the phenomenon by providing a tool to develop critical awareness of these problems. By reviewing scientific articles, we collected information on the use of licit and illicit substances among professional and non-professional athletes, showing a widespread scenario also based on false myths. The use of supplements, drugs and doping substances represents a complex and still debated issue, that deserves greater consideration among both sportsmen and health operators. A more critical and informed approach to these topics can support empowerment and a conscious use of drugs by respecting eating habits, own health and healthy lifestyles.

Successful Treatment of Kaposi Sarcoma-Associated Herpesvirus Inflammatory Cytokine Syndrome After Kidney-Liver Transplant: Correlations With the Human Herpesvirus 8 miRNome and Specific T Cell Response.

After transplant, patient infection with human herpesvirus 8 (HHV-8) and Kaposi sarcoma-associated herpesvirus (KSHV) is known to cause aggressive tumors and severe nonneoplastic complications. These latter syndromes are driven by HHV-8/KSHV lytic reactivations and related hyperinflammatory host responses typically characterized by high viral loads, elevated levels of cytokines and other inflammation biomarkers, cytopenia, organ failure, high fever, and worsening conditions (with no evidence of B cell neoplasias). These disorders are associated with a high mortality rate, often due to lack of prompt diagnosis, effective therapeutic approaches, and adequate follow-up. These features resemble most of those defining the so-called KSHV-associated inflammatory cytokine syndrome (KICS), which was recently recognized in patients positive for human immunodeficiency virus (HIV). In this report, we describe-for the first time-a case of a KICS-like nonneoplastic recurrent complication occurring after transplant in an HIV-negative patient that was successfully treated by a combination of anti-CD20 monoclonal therapy, antivirals, and modification of the immunosuppressive regimen. In addition to clinical and laboratory findings collected during 3-year follow-up, we report novel experimental data on HHV-8-specific T cell dynamics and circulating microRNA profile, showing correlations with clinical course and other laboratory markers (including viral load, C-reactive protein, and cytokine levels), providing useful information about abnormal cellular and cytokine dynamics underlying HHV-8-associated inflammatory disorders in posttransplant patients.

The steroid response to human chorionic gonadotropin (hCG) stimulation in men with Klinefelter syndrome does not change using immunoassay or mass spectrometry.

PURPOSE: Liquid-chromatography tandem mass-spectrometry (LC-MS/MS) was developed in parallel to Immunoassays (IAs) and today is proposed as the "gold standard" for steroid assays. Leydig cells of men with Klinefelter syndrome (KS) are able to respond to human chorionic gonadotropin (hCG) stimulation, even if testosterone (T) production was impaired. The aim was to evaluate how results obtained by IAs and LC-MS/MS can differently impact on the outcome of a clinical research on gonadal steroidogenesis after hCG stimulation. METHODS: A longitudinal, prospective, case-control clinical trial. (clinicaltrial.gov NCT02788136) was carried out, enrolling KS men and healthy age-matched controls, stimulated by hCG administration. Serum steroids were evaluated at baseline and for 5 days after intramuscular injection of 5000 IU hCG using both IAs and LC-MS/MS. RESULTS: 13 KS patients (36 ± 9 years) not receiving T replacement therapy and 14 controls (32 ± 8 years) were enrolled. T, progesterone, cortisol, 17-hydroxy-progesterone (17OHP) and androstenedione, were significantly higher using IAs than LC-MS/MS. IAs and LC-MS/MS showed direct correlation for all five steroids, although the constant overestimation detected by IAs. Either methodology found the same 17OHP and T increasing profile after hCG stimulation, with equal areas under the curves (AUCs). CONCLUSIONS: Although a linearity between IA and LC-MS/MS is demonstrated, LC-MS/MS is more sensitive and accurate, whereas IA shows a constant overestimation of sex steroid levels. This result suggests the need of reference intervals built on the specific assay. This fundamental difference between these two methodologies opens a deep reconsideration of what is needed to improve the accuracy of steroid hormone assays.

Interleukin 28B polymorphisms as predictors of sustained virological response in chronic hepatitis C: systematic review and meta-analysis.

Polymorphism of interleukin 28B gene represents a powerful outcome predictor for interferon-based regimens in hepatitis C virus infection. However, some studies report conflicting results. The predictive value of interleukin 28B genotype over the outcome interferon-α/ribavirin treatment was thoroughly evaluated and compared with virological predictors of response. Literature revision was performed on PubMed. Pooled odds ratios (ORs) were calculated by fixed- or random-effects models. Heterogeneity and publication bias were also assessed. Sixty-two eligible papers including 20 290 patients were retrieved. Both polymorphisms (rs12979860 and rs8099917) were strongly associated with response (OR=4.09 and 4.00, respectively), however, the association was weaker for subjects infected with viral genotypes 2 and 3 (OR=1.52 and 1.49, respectively). Compared with interleukin 28B genotype, the association with response was lower for baseline viremia (OR=2.15) and higher for rapid virological response (OR=13.86). These results provide a critical evaluation of interleukin 28B genotype as a pharmacogenetic predictor in hepatitis C patients.

A new challenge for urinary free light chains: assessment of the upper reference limit in healthy subjects.

OBJECTIVE: Free light chains (FLCs) can be measured in both urine (uFLC) and serum (sFLC) in immunochemistry. We aim to compare FLC levels in serum and urine assessed among healthy volunteers and measured upper reference limits (URLs) of urinary FLC to creatinine ratio (uFLC/uCr) in mg/g to compare with the manufacturer's recommended URLs. PATIENTS AND METHODS: Eligibility criteria: normal serum and urine FLC measure and negative serum/urinary immunofixation. Immunoturbidimetry was used to assess both κ and λ FLCs. The URLs were calculated with the 97.5th percentile of uFLC concentrations according to the Clinical and Laboratory Standards Institute recommendations. RESULTS: 126 healthy subjects (median age 46 years, 62% females) met the inclusion criteria. Median concentrations of κ and λ sFLCs were similar both for males and females without significant differences. κ and λ uFLCs were significantly higher in males than in females (p < 0.001 and p = 0.004, respectively). Slower clearance for λ FLC compared to κ FLC was observed with an increased κ/λ uFLC ratio in both males and females. URLs for male and female subjects: κ uFLC mg/g uCr = 34.35 vs. 23.18, and λ uFLC mg/g uCr = 3.59 vs. 1.96, respectively compared well with manufacturer's URLs. CONCLUSIONS: FLC catabolism is gender-dependent and occurs less rapidly in λ FLC than in κ FLC. The determination of the URL of uFLC, as uFLC/uCr, in healthy subjects in morning urine, proved to be consistent with the manufacturer's recommendations, but with a significant difference according to gender.

The role of laboratory medicine in a value-based healthcare system: the example of heart failure patient management in the Italian context.

OBJECTIVE: As of today, healthcare systems worldwide face severe challenges that undermine their sustainability. The value-based healthcare (VBHC) approach has been proposed as a strategic and methodological framework to ensure the delivery of the best patient outcomes with economic efficiency. Through the illustrative example of B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) for heart failure (HF) patient management in the context of the Italian National Healthcare system, this article explores the role that in vitro diagnostics (IVDs) can play in enabling value-based care models. SUBJECTS AND METHODS: 14 healthcare professionals representing the relevant professional figures involved in HF patient management met to revise the current HF patient journey and design a new care pathway that, leveraging on BNP/NT-proBNP, reflects the VBHC principles. RESULTS: The literature recognizes the dosage of BNP/NT-proBNP as the gold stan-dard for diagnosing HF. However, as of today, these IVDs are not employed at their full potential regarding HF patient management. A new patient journey is proposed so that patients are diagnosed early and properly monitored in the aftermath of hospitalization, improving outcomes at contained costs. CONCLUSIONS: As testified by the example of HF patient management in Italy, laboratory medicine can represent a lever for adopting value-based care models. Still, large-scale adoption of VBHC will call for structural reforms that revise how healthcare delivery is organized, measured, and reimbursed.

Markers of bone turnover for the prediction of fracture risk and monitoring of osteoporosis treatment: a need for international reference standards.

UNLABELLED: The International Osteoporosis Foundation (IOF) and the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) recommend that a marker of bone formation (serum procollagen type I N propeptide, s-PINP) and a marker of bone resorption (serum C-terminal telopeptide of type I collagen, s-CTX) are used as reference analytes for bone turnover markers in clinical studies. INTRODUCTION: Bone turnover markers (BTM) predict fracture risk, and treatment-induced changes in specific markers account for a substantial proportion of fracture risk reduction. The aims of this report were to determine their clinical potential in the prediction of fracture risk and for monitoring the treatment of osteoporosis and to set an appropriate research agenda. METHODS: Evidence from prospective studies was gathered through literature review of the PUBMED database between the years 2000 and 2010 and the systematic review of the Agency for Healthcare Research and Quality up to 2001. RESULTS: High levels of BTMs may predict fracture risk independently from bone mineral density in postmenopausal women. They have been used for this purpose in clinical practice for many years, but there is still a need for stronger evidence on which to base practice. BTMs provide pharmacodynamic information on the response to osteoporosis treatment, and as a result, they are widely used for monitoring treatment in the individual. However, their clinical value for monitoring is limited by inadequate appreciation of the sources of variability, by limited data for comparison of treatments using the same BTM and by inadequate quality control. IOF/IFCC recommend one bone formation marker (s-PINP) and one bone resorption marker (s-CTX) to be used as reference markers and measured by standardised assays in observational and intervention studies in order to compare the performance of alternatives and to enlarge the international experience of the application of markers to clinical medicine. CONCLUSION: BTM hold promise in fracture risk prediction and for monitoring treatment. Uncertainties over their clinical use can be in part resolved by adopting international reference standards.

[Analytical quality in biological monitoring of workers exposed to chemicals: experience of the Prevention and Safety at the Workplace Service in Modena]. / Qualità del dato analitico nel monitoraggio biologico dei lavoratori esposti a sostanze chimiche: esperienza del Servizio Prevenzione e Sicurezza Ambienti di Lavoro della Azienda USL di Modena.

BACKGROUND: The quality of laboratory data is one of the main factors in guaranteeing efficacy of biological monitoring. OBJECTIVES: To analyze the quality of laboratory data used for biological monitoring of exposed workers. METHODS: A survey involving 18 companies employing 945 workers in the area of Modena, Italy, was carried out in 2008. RESULTS: Most of the 9 private laboratories receiving biological samples did not perform directly part or all of the laboratory assessments requested, but this was not indicated in the final report. Major problems were observed in the application of internal quality control, and only one laboratory participated in external quality assessment for blood lead measurements. CONCLUSIONS: Our results raise major concerns on the traceability and reliability of laboratory assessments performed for biomonitoring of exposed workers. Systematic evaluation of the quality of analytical data would be highly recommendable.

Human chorionic gonadotropin stimulation gives evidence of differences in testicular steroidogenesis in Klinefelter syndrome, as assessed by liquid chromatography-tandem mass spectrometry.

BACKGROUND: Men with Klinefelter syndrome (KS) show hypergonadotropic hypogonadism, but the pathogenesis of hypotestosteronemia remains unclear. Testicular steroidogenesis in KS men was evaluated over three decades ago after human chorionic gonadotropin (hCG) stimulation, but inconclusive results were obtained. Intriguingly, some recent studies show increased intratesticular testosterone concentrations in men with KS. OBJECTIVE: To analyze serum steroid profile, as a proxy of testicular steroidogenesis, after hCG stimulation in KS compared with control men. DESIGN: A prospective, longitudinal, case-control, clinical trial. METHODS: Thirteen KS patients (36±9 years) not receiving testosterone (TS) replacement therapy and 12 eugonadic controls (32±8 years) were enrolled. Serum steroids were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) at baseline and for five consecutive days after intramuscular injection of 5000IU hCG. RESULTS: Progesterone (P), 17-hydroxyprogesterone (17OHP), TS, and estradiol (E2) showed a significant increase (P<0.001) after hCG stimulation in both groups. On the contrary, androstenedione (AS) and dehydroepiandrosterone did not increase after hCG stimulation. The 17OHP/P ratio increased in both groups (P<0.001), the TS/AS ratio (17ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3) activity) did not increase after hCG in any group, and the E2/TS ratio (aromatase activity) increased significantly in both groups (P=0.009 in KS and P<0.001 in controls). Luteinizing hormone decreased after hCG in both groups (P=0.014 in KS and P<0.001 in controls), whereas follicle-stimulating hormone decreased only in control men (P<0.001). CONCLUSION: This study demonstrates for the first time using LC-MS/MS that Leydig cells of KS men are able to respond to hCG stimulation and that the first steps of steroidogenesis are fully functional. However, the TS production in KS men is impaired, possibly related to reduced hydroxysteroid deydrogenase activity due to an unfavorable intratesticular metabolic state.

The effect of a ferric iron complex on isolated rat-liver mitochondria. III. Mechanistic aspects of iron-induced calcium efflux.

Addition of iron(III)-gluconate complex to isolated rat liver mitochondria induced a net efflux of Ca2+ which was not inhibited by ruthenium red. This process resulted in the enhancement of Ca2+ cycling and a consequent membrane potential drop. Under these experimental conditions the content of mitochondrial glutathione did not appear to be critically modified, whereas an extensive oxidation of mitochondrial pyridine nucleotides was parallelly detected. Iron failed to induce appreciable changes in the oxidation level of pyridine nucleotides in mitochondria isolated from rats fed a selenium deficient diet, a condition in which mitochondrial glutathione peroxidase resulted inhibited by 80%. The iron-induced Ca2+ release in Se-deficient mitochondria appeared largely delayed and the membrane potential of these mitochondrial did not present gross alterations. Iron was also found to induce a transient increase in the mitochondrial cyanide-insensitive oxygen consumption. This effect was largely prevented by the addition of the hydrogen peroxide scavenger catalase. It was concluded that iron induced the activation of a specific Ca2+ efflux pathway via the oxidation of pyridine nucleotides due to the hydrogen peroxide metabolism by glutathione enzyme system.

The effect of ferric iron complex on isolated rat liver mitochondria. I. Respiratory and electrochemical responses.

Addition of iron(III)-gluconate complex to isolated rat liver mitochondria resulted in an increased iron content of mitochondria. Iron was accumulated through a relatively fast process (maximal uptake in less than 2 min incubation) by an energy-independent mechanism. The in vitro iron overload of mitochondria was associated with enhancement in the oxygen consumption, which was due to the induction of lipoperoxidative processes catalyzed by iron. It was found that a concentration of iron as low as 0.1 mM elicits a consistent production of malondialdehyde in mitochondria. Concomitant with the induction of lipoperoxidation a progressive fall in the mitochondrial membrane potential was observed. The occurrence of energy-consuming processes as a consequence of iron addition, and particularly the enhancement of endogenous Ca2+ cycling across the membrane, was suggested as the cause of the membrane potential drop.

The effect of ferric iron complex on isolated rat liver mitochondria. II. Ion movements.

It has been found that addition of iron(III)-gluconate complex to rat liver mitochondria disturbed the mitochondrial Ca2+ transport. Indirect evidence when the changes in the membrane potential during the transport of Ca2+ were followed, as well as direct evidence, when the fluxes of Ca2+ were monitored by a Ca2+-selective electrode, indicated that this iron complex induced an efflux of Ca2+ from liver mitochondria. The mechanisms by which iron induced Ca2+ release appeared to be linked to the induction of lipoperoxidation of mitochondrial membrane. The mitochondrial membrane, however, did not become irreversibly damaged under these conditions, as indicated by its complete repolarization. It was also shown that the induction by iron of lipoperoxidation brought about an efflux of K+ from mitochondria.

Dietary iron deficiency in the rat. II. Recovery from energy metabolism derangement of the hepatic tissue by iron therapy.

Severe iron deficiency in rats was found to be associated with abnormal lipid accumulation in the liver and impairment of the oxidative metabolism in the hepatic tissue. Iron therapy, consisting in oral administration to iron-deficient 4-week-old rats of iron succinyl-albumin complex, at a daily dose of 10 mg/kg body weight, over a period of 7 days, almost completely corrected these functional anomalies. This treatment fully reverted severe anemia associated with iron deficiency. The level of iron in the hepatic tissue and in the mitochondrial fraction also increased largely. By contrast, no significant improvement in the lowered level of cytochromes occurred. Iron supplements significantly decreased the abnormal level of liver total lipids and serum triglycerides. Concomitantly, iron repletion fully reverted the partial loss of coupled function in isolated mitochondria and the energy state perturbation of the liver. A close relationship among abnormal lipid accumulation, impairment of mitochondrial oxidative phosphorylation and energy derangement in the hepatic cell in this experimental model of severe dietary iron deficiency anemia appears to be likely.

Mitochondrial inner membrane permeability changes induced by octadecadienoic acid hydroperoxide. Role of mitochondrial GSH pool.

The effect of exogenous octadecadienoic acid hydroperoxide (HPODE) on the functional properties of inner membrane of isolated rat liver mitochondria, as evaluated by the measurement of the membrane potential (delta psi) has been studied. Very low concentrations of HPODE (1.5-4.5 nmol/mg prot.) do not modify the delta psi of control mitochondria appreciably while bringing about the drop of delta psi, in a concentration-dependent mode, in mitochondria with a GSH level diminished by approx. 60%. Mitochondrial GSH depletion was obtained by intraperitoneal administration of buthionine sulfoximine, a specific inhibitor of GSH synthesis, to rats. The presence in the incubation system of GSH-methyl ester which normalizes mitochondrial GSH, fully prevents any drop in levels of delta psi induced by HPODE. The same protective effect has been presented by EGTA, which chelates the available Ca2+. Neither an antioxidant nor a specific inhibitor of mitochondrial phospholipase A2 are able to prevent the HPODE effect. From the results obtained we can assume that HPODE itself, at the concentrations used here, induces permeability changes in the inner membrane, with the loss of coupled functions, when the GSH mitochondrial level is below a critical value.

Perturbation in liver mitochondrial Ca2+ homeostasis in experimental iron overload: a possible factor in cell injury.

The functional state of isolated mitochondria and specifically the integrity of the inner membrane, were investigated in the liver of rats made siderotic by dietary supplementation with carbonyl iron. The concentration of iron in the hepatic tissue increased progressively up to nearly 40 days and reached a steady-state level. When the iron content reached a threshold value (higher than 90 nmol/mg protein) the occurrence of in vivo lipid peroxidation in the mitochondrial membrane was detected. This process did not result in gross alterations in the mitochondrial membrane, as indicated by electron microscopy, phosphorylative capability and membrane potential measurements. On the contrary, the induction of lipoperoxidative reaction appeared to be associated with the activation of Ca2+ release from mitochondria. This was shown to occur as a consequence of rather subtle modifications in the inner membrane structure via a specific efflux route, which appeared to be linked to the oxidation level of mitochondrial pyridine nucleotides. The induction of this Ca2+ release from iron-treated mitochondria resulted in enhancement of Ca2+ cycling, a process which dissipates energy to reaccumulate into mitochondria the released Ca2+. The perturbation in mitochondrial Ca2+ homeostasis reported here may be a factor in the onset of cell damage in this experimental model of hepatic iron overload.

Transmembrane potential of liver mitochondria from hexachlorobenzene-and iron-treated rats.

The respiratory parameters and the membrane potential of liver mitochondria from rats treated with either hexachlorobenzene, iron or hexachlorobenzene plus iron, to induce experimental porphyria, have been studied. Partial uncoupling of oxidative phosphorylation has been observed in mitochondria from hexachlorobenzene- and hexachlorobenzene plus iron-treated rats. Direct evidence has been presented that this uncoupling is due to the action of pentachlorophenol endogenously formed by metabolism of hexachlorobenzene. No irreversible damage of mitochondria membrane has been revealed under both these conditions. Normal oxidative phosphorylation has been found in mitochondria from rats treated with iron alone. In contrast, they presented an anomalous membrane potential, fully restored by oligomycin. A possible involvement of lipid peroxidation process, induced by iron, in causing these abnormalities has been suggested.

Phenotypic characteristics and tendency to apoptosis of peripheral blood mononuclear cells from HIV+ long term non progressors.

The aim of this study was to analyze (i) phenotype, (ii) in vitro spontaneous and induced apoptosis, (iii) glutathione (GSH) intracellular content and (iv) inhibitors of apoptosis of potential therapeutical use in peripheral blood mononuclear cells (PBMC) from HIV+ long term non progressors (LTNP), in comparison with progressors (HIV+P) and seronegative controls (HIV-). Three groups of subjects were studied: 15 HIV+P (patients losing >150 CD4+/year), 9 LTNP (subjects infected by HIV for at least 7 years without clinical and immunological signs of progression, with a mean of 898 CD4+/microL) and 18 HIV-. All subjects were living in a large community for former drug addicts, and were matched for age and sex. We used flow cytometry for analyzing PBMC phenotype and apoptosis; high performance liquid chromatography for measuring intracellular GSH content. PBMC phenotype of LTNP shared characteristics with those of both HIV- and HIV+P. Indeed, LTNP showed a normal number CD4+ cells (an inclusion criteria), but significantly increased numbers of CD8+ lymphocytes, activated T cells, CD19+, CD5+ B lymphocytes and CD57+ cells, as well as a decrease in CD19+, CD5- B lymphocytes and CD16+ cells. In LTNP, spontaneous apoptosis was similar to that of HIV- and significantly lower than that of HIV+P. Adding interleukin-2 (IL-2) or nicotinamide (NAM) significantly decreased spontaneous apoptosis in LTNP and HIV+P. Pokeweed mitogen-induced apoptosis was also similar in LTNP and HIV-, but significantly lower than that of HIV+P. In HIV+P, but also in LTNP, spontaneous apoptosis was inversely correlated to the absolute number and percentage of CD4+ cells and directly correlated to the number and percentage of activated T cells present in peripheral blood. GSH intracellular content was greatly decreased in PBMC from HIV+P and slightly, but significantly, reduced in LTNP. Adding 2-deoxy-D-ribose, an agent provoking apoptosis through GSH depletion, to quiescent PBMC resulted in similar levels of massive cell death in the three groups. This phenomenon was equally prevented in the three groups by N-acetyl-cysteine but not by IL-2. A complex immunological situation seems to occur in LTNP. Indeed, PBMC from LTNP are characterized by a normal in vitro tendency to undergo apoptosis despite the presence of a strong activation of their immune system, unexpectedly similar to that of HIV+P. Our data suggest that NAM and IL-2 are possible candidates for reducing spontaneous apoptosis in HIV infection.