High Irisin levels in nondiabetic HIV-infected males are associated with insulin resistance, nonalcoholic fatty liver disease, and subclinical atherosclerosis

OBJECTIVE

HIV infection is associated with an increased risk of cardiovascular disease. Irisin is a miokyne secreted by skeletal muscle, which may influence insulin homeostasis, nonalcoholic fatty liver disease (NAFLD) and atherosclerosis. Our objective was to evaluate the relationships between serum irisin, insulin homeostasis, NAFLD and subclinical atherosclerosis in HIV-infected males.

DESIGN

Cross-sectional study in a cohort of HIV-infected patients.

PATIENTS

Inclusion criteria: men older than 18 years; antiretroviral therapy (ART) -naïve or on effective ART (<50 HIV-1 RNA copies/mL) without changes in the previous 6 months; no diabetes or hepatitis C.

MEASUREMENTS

Irisin was measured by enzymatic immunoassay (Phoenix Pharmaceuticals), insulin sensitivity by homeostasis model assessment of insulin resistance (HOMA-IR), as well as the 2-hour continuous infusion of glucose with model assessment (CIGMA-HOMA). Hepatic steatosis was measured by 1-H magnetic resonance spectroscopy, subclinical atherosclerosis by evaluation of carotid intima-media thickness (C-IMT), measured by Ultrasonography.

RESULTS

Eight nine men (age 42.0 ± 8.3 years, duration of HIV infection 7.9 ± 5.6 years, CD4 count 547 ± 279 cells/mL) were included. Circulating irisin was positively related to HOMA-IR and CIGMA-HOMA, hepatic triglyceride content, and to VAT/SAT ratio. Higher irisin concentrations were associated with higher C-IMT, although this association did not persist in multivariate analysis. Lipodystrophy and a higher baseline PAI-1 concentration were independently associated with C-IMT.

CONCLUSIONS

In male HIV patients without diabetes, higher irisin concentrations are positively associated with insulin resistance, NAFLD and subclinical atherosclerosis. However, waist-hip-ratio is the main determinant of insulin resistance, and PAI-1 and lipodystrophy were the strongest determinants of IMT in this population.

Obesity and fat distribution imply a greater systemic inflammatory response and a worse prognosis in acute pancreatitis

BACKGROUND AND AIMS

Acute pancreatitis (AP) is a systemic inflammatory disease. It is already known that obesity and central fat distribution are related to the severity of AP, but the intimate mechanism of this relationship remains unknown. Obesity and central fat distribution are associated with an inflammatory state that could amplify the systemic inflammatory response (SIR) in AP. The aim of this study was to investigate how obesity and body fat distribution correlate with the SIR and severity of AP.

METHODS

85 consecutive patients with AP were studied. Body mass index, body fat distribution and previous comorbidity were obtained at admission. The SIR was assessed by the serum levels of interleukin (IL)-1beta, IL-1ra, IL-6, IL-8, IL-10, IL-12p70, tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein. Serum concentrations of the previously mentioned cytokines were also determined in a control group of 40 healthy volunteers.

RESULTS

63 patients (74%) had mild AP and 22 patients (26%) had severe AP. All the cytokines except IL-12p70 and TNF-alpha were increased in the AP group in comparison with the control group. The SIR was significantly increased in patients with severe AP. Obese patients and patients with central fat distribution had significantly more comorbidity, a higher proportion of severe AP and more intense SIR. Patients with comorbidity had a significantly higher proportion of severe AP and more SIR.

CONCLUSION

The severity of AP in obese patients and in patients with central fat distribution seems to be related to the comorbidity and the amplification of SIR. and IAP.

Potential diagnostic value of methylation profile in pleural fluid and serum from cancer patients with pleural effusion

BACKGROUND

The objective of this study was to investigate the diagnostic value of methylation profiles for discrimination between malignant and benign pleural effusions. A secondary objective was to examine the concordance of methylation in samples of serum and pleural fluid.

METHODS

The authors used methylation-specific polymerase chain reaction (MSP) analysis to examine the promoter methylation status of 4 genes in patients with pleural effusion: death-associated protein kinase (DAPK), Ras association domain family 1A (RASSF1A), retinoic acid receptor beta (RARbeta), and p16/INK4a. Pleural effusions were collected from 87 patients who had their diagnoses confirmed on cytologic and/or histologic examinations and clinical evolution. Pleural effusions were classified as malignant (n = 53 patients) or benign (n = 34 patients).

RESULTS

Methylation was detected in serum from 45.3% of patients with malignant pleural effusions and from 0% of patients with benign pleural effusions, and it was detected in pleural fluid samples from 58.5% of patients with malignant pleural effusions and from 0% of patients with benign pleural effusions (P = .001). The sensitivity of MSP was greater than that of cytologic examination alone (39.1%; P = .001). When MSP was used together with cytologic examination, sensitivity increased to 69.8% (P = .001).

CONCLUSIONS

Cell-free methylated DNA in pleural fluid can be detected in patients with neoplastic malignancy in a single extraction by thoracocentesis. Adequate management of the extracted pleural fluid can provide a rapid and reliable diagnosis in patients with pleural effusions who have suspected malignancy. MSP, used together with cytologic examination, may obviate the need for other invasive diagnostic tests.

Immunovirologic consequences and safety of short, non-structured interruptions of successful antiretroviral treatment

OBJECTIVES

The aim was to evaluate the safety of short antiretroviral treatment interruptions and their virologic and immunologic consequences in HIV-infected adults on highly active antiretroviral treatment (HAART) with suppressed viral replication. The viral efficacy upon reintroduction was also evaluated.

PATIENTS AND METHODS

All patients with undetectable viral load while on HAART were prospectively followed to detect any treatment interruption. We analysed viral and cellular kinetics, incidence of resistance mutations, clinical outcome and results after therapy resumption.

RESULTS

Twenty patients were included, mean time since HIV diagnosis was 95 months and time with undetectable viral load 16 months. Treatment was interrupted because of adverse effects, cancer, tuberculosis or patient will. Treatment was reintroduced after 4 weeks using, if possible, the same combination. HIV viral load was detectable on day 28 after interruption in 18 patients (90%). Median of CD4 cell count (p25-p75) decreased from 478/mm3 (96-716) to 257/mm3 (118-663) (p=0.5). Resistance mutations were found in 9 patients (45%) after interruptions. Treatment was reintroduced in 14 patients; all of them achieved viral suppression.

CONCLUSIONS

In patients receiving HAART who have undetectable viral load, an interruption, no longer than 4 weeks, due to any intercurrent problem seems to be safe. Response to resumption can usually be achieved. Due to the frequent development of resistance, a genotypic test during interruption might be helpful.

Different profile of cytokine synthesis according to the severity of acute pancreatitis

AIM: To evaluate the cellular synthetic ability of cytokines involved in pro- and anti-inflammatory reactions in patients with AP.

METHODS: Sixty-seven patients with AP (16 severe, 51 mild) and 10 controls were included in the study. Cultures of whole blood were performed in samples obtained within the first 72 h from the onset of pain. Serum levels of interleukins (IL) 6, 8, 10, and TNF-α were measured at baseline and in the supernatant of cultures with (functional reserve) or without stimulation with phytohemaglutinin.

RESULTS: Basal levels of cytokines were significantly higher in patients with severe AP. A significant increase of all pro-inflammatory cytokines vs basal levels was observed in the supernatant after 24 h of whole blood cultures in patients, but not in controls. In contrast, IL-10 increased significantly in the supernatant of cultures only in patients with mild AP. Cells showed a statistically significant functional reserve for all IL in patients with mild, but only for pro-inflammatory cytokines in patients with severe AP.

CONCLUSION: A marked activation of immune system may be observed in patients with AP, being balanced between pro- and anti-inflammatory cytokines in patients with mild but not severe AP. A reduced functional reserve for the synthesis of IL-10 may be observed in patients with severe AP, which might lead to a worst prognosis.