Metabolic-associated fatty liver disease and hepatocellular carcinoma: a prospective study of characteristics and response to therapy

BACKGROUND AND AIM

The rising incidence of hepatocellular carcinoma (HCC) in Australia is related to increasing rates of metabolic-associated fatty liver disease (MAFLD). This study aimed to prospectively characterize the metabolic profile, lifestyle, biometric features, and response to treatment of HCC patients in an Australian population.

METHOD

Multicenter prospective cohort analysis of newly diagnosed HCC patients at six multidisciplinary team meetings over a 2-year period.

RESULTS

Three hundred and thirteen (313) newly diagnosed HCC patients with MAFLD (n = 77), MAFLD plus other liver disease (n = 57) (the "mixed" group), and non-MAFLD (n = 179) were included in the study. Alcohol-associated liver disease (ALD) (43%) and MAFLD (43%) were the most common underlying liver diseases. MAFLD-HCC patients were older (73 years vs 67 years vs 63 years), more likely to be female (40% vs 14% vs 20%), less likely to have cirrhosis (69% vs 88% vs 85%), showed higher ECOG, and were less likely to be identified by screening (29% vs 53% vs 45%). Metabolic syndrome was more prevalent in the MAFLD and mixed groups. The severity of underlying liver disease and HCC characteristics were the same across groups. While the MAFLD population self-reported more sedentary lifestyles, reported dietary patterns were no different across the groups. Dyslipidemia was associated with tumor size, and those taking statins had a lower recurrence rate.

CONCLUSION

Equal to ALD, MAFLD is now the most common underlying liver disease seen in HCC patients in Australia. Future HCC prevention screening and treatment strategies need to take this important group of patients into consideration.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

RARE-11. 60 years single centre experience of craniopharyngioma management

Adamantinomatous craniopharyngiomas are challenging intracranial tumours associated with significant morbidity. Management includes surgery and radiotherapy, with a shift towards more conservative surgery in recent years, aimed at preserving hypothalamic function. The West Midlands Regional Children’s Tumour Registry collects detailed clinical, pathological and follow up information on patients treated within the region from 1957. 52 cases (26 male, 26 female) of craniopharyngioma treated at Birmingham Children’s Hospital 1957-2018, were identified, with further clinical details obtained from patient records, where available. Visual symptoms were the commonest presenting feature (63%), followed by headache (48%), vomiting (31%), neurological symptoms (31%) and features of endocrine disorders (21%) with a median symptom duration of 6 months (range <1-24). Initial management was with gross total resection (GTR) in 14 patients, subtotal resection in 22 patients and subtotal resection with adjuvant radiotherapy in seven patients. Two patients received radiotherapy without resection, and five patients underwent cystic drainage procedures alone. Two patients initially underwent shunt insertion alone, but received radiotherapy at progression. 30 (58%) patients underwent relapse/progression, with a median time to progression of 1.2 years (range 0.2-6.3). 15 had further surgery. Radiotherapy was used in 14/15 patients who had not previously received radiotherapy, with the other undergoing a GTR. To date 10 patients have died, nine from tumour related reasons and one from pulmonary embolism. Where data was available at follow up, all patients had at least one endocrinopathy, with 38/45 patients having diabetes insipidus. Hypothalamic obesity was identified in 14/36 (39%) patients with sufficient records, with this more common in those undergoing GTR (7/9 (78%)) compared to other surgical procedures (7/27)(26%)(p<0.05). Three patients have developed neurovascular complications and three fatty liver disease. This experience is consistent with the literature and supports the increasing usage of hypothalamic sparing surgical management.

Early Cerebrovascular Ultrasonography as a Predictor of Hemorrhagic Transformation After Thrombectomy

OBJECTIVES

To determine the predictive value of early transcranial color-coded sonography (TCCS) for intracranial hemorrhage (ICH) in patients with large artery occlusion (LAO) stroke of carotid circulation, who were submitted to endovascular therapy (EVT) with successful reperfusion.

MATERIALS AND METHODS

Retrospective study evaluating a cohort of consecutive stroke patients with LAO of the carotid circulation that were recanalyzed with EVT. We measured angle-corrected peak systolic velocities, end-diastolic velocities and mean flow velocities (PSV, EDV and MFV) of the symptomatic and asymptomatic middle cerebral artery (MCA). The ratio between MFV of the symptomatic MCA and MFV of the asymptomatic MCA (MCA-Ra) was calculated. Parenchymal hematoma in the 24 hours control CT was considered as ICH. Univariate associations and multivariate analyses were used to identify early independent predictors for ICH among TCCS findings.

RESULTS

We included 234 patients, mean age 72.5 (SD 12.6) years, 52.1% male. The mean time between recanalization and TCCS was 12.3 hours (range 3-22). Patients who developed postinterventional ICH showed a higher MCA-Ra (1.02 ± 0.26 vs 1.16 ± 0,21, p = 0.036). In multivariate analysis, only higher MCA-Ra remained independently associated with postinterventional ICH (OR: 6.778, 95%CI: 1.152-39.892, p = 0.034). A value of MCA-Ra ≥ 1,05 was associated with ICH, showing a sensitivity of 81.3% and a specificity of 65.9%; the AUC based of the ROC analysis was 0.688 (95% CI 0.570-0.806).

CONCLUSION

TCCS performed within the first 24 hours after stroke onset can help to predict hemorrhagic transformation in patients with LAO.

Device therapy guided by implantable loop recorders: predictors of bradyarrhythmic events

Background

Implantable loop recorders (ILR) improved diagnostic yield in unexplained syncope patients (pts). Data on possible predictive factors for bradycardia requiring device implantation in these pts is limited. We aim to identify clinical predictors for device implantation due to a significant bradyarrhythmia in patients who underwent ILR insertion for the study of syncopal/presyncopal (S/pS) events.

Methods

Single-center retrospective study of patients who implanted an ILR for the study of unexplained S/pS episodes between 2013 and 2018. The primary endpoint was a documented bradyarrhythmia requiring device implantation during the follow-up.

Results

A total of 251 pts were included. Mean age was 68±15 years and 53% were female. The majority of pts (220; 88%) had normal ejection fraction. Fifty-two (21%) pts had atrial fibrillation (AF). Regarding basal electrocardiographic characteristics, 34 (14%) pts had 1st degree auriculo-ventricular block (AVB), 31 (12%) pts had left bundle branch block (L-BBB), 22 (9%) pts had R-BBB and 13 (5%) pts had bifascicular block.

During a median follow-up of 20 (IQR 9–34) months, 74 (29%) pts required device implantation because of a significant bradyarrhythmia (92% pacemaker, 4% CRT, 4% ICD). Median duration from ILR until device implantation was 5 (IQR 1–10) months. The indications were sick-sinus-syndrome in 47 (64%) pts, advanced AV block in 23 (31%) pts and symptomatic slow AF in 4 (5%) pts.

Patients who required device implantation were older (73±12 vs 66±15 years, p <0.001), had more hypertension (73% vs 59% p=0.048), a higher prevalence of AF (34% vs 15% p=0.001) and a lower glomerular filtration rate (GFR<60 ml/min: 32% vs 21%, p=0.047). They also had more 1st AVB (22% vs 11%, p=0.026) and intraventricular conduction disturbances (38% vs 25%, p=0.025). There was a trend for a higher device implantation in pts with concomitant 1st AVB and left anterior fascicular block (7% vs 2%, p=0.063)

In a logistic regression model, age >75 years (HR: 1.7; 95% CI: 1.1–2.8) and the presence of AF (HR: 1.8; 95% CI: 1.1–3.0) were independent predictors for device implantation.

Conclusion

An older age and the presence of AF were independent predictors for device therapy in pts who implanted an ILR for the study of S/pS. These factors may identify a higher risk group and should be considered in the initial workup of these pts.

Funding Acknowledgement

Type of funding source: None

Impact of the African Organisation for Research and Training in Cancer on Improving Cancer Care on the Continent: 15-Year History

Background and context: African Organisation for Research and Training in Cancer (AORTIC) seeks to become the continent's preeminent nonprofit organization working for cancer control. Established in 1982, and gaining exponential momentum since 2003. Milestones achieved include placing cancer control on the continent's health agenda. Main activities have been to foster collaboration for research and training, advocacy, palliative and psychosocial care, survivor groups, educative meetings for local and international cancer care professionals. Strategy/Tactics: To demonstrate impact of AORTIC on the continent over the past one and a half decades as a successful nonprofit organization aimed at reducing impact of cancer in Africa. Position our organization to lead the continent with home grown innovation to sensitize the cancer workforce to needs of our patients and countries by developing strategies that impact on improving cancer care across the continuum, research priorities and capabilities, professional development, including advocacy, survivorship, acting as a consultative mouth piece and authority on cancer control needs of Africa. Program/Policy process: 11 successful international biennial cancer conferences in Africa, with a steady increase in attendance from 300 to +900 delegates, 12 to 95 sessions, +3000 abstracts presented over 15 years. Last meeting labeled as; “This meeting is high-value; at the level of the best oncology meetings as ASCO and ESMO”. Regional training in pathology, oncology, psycho-oncology, palliative care, advocacy, prevention and early diagnosis. Regional meetings: Senegal, Tanzania, Nigeria, Angola, Mozambique and Cape Verde. Special interest groups: radiation, pathology, nursing, pediatrics and advocacy promoting professional and research development activities. African cancer leadership mentoring academies for young investigators - +40 participants to date. Grants for qualifying members to participate in external training workshops. 39 newsletters - translated into French and Portuguese. Memberships - span across the African continent, Europe, North America and Australia and organizations - 500 individual and close to 20 organizational members. Hosted Africa regional meetings at UICC WCC since 2014. Active on social media - +1300 followers. Publications: Cancer Plan for the African Continent 2013-2017 Handbook for Cancer Research in Africa Cancer Advocacy Training Toolkit for Africa AORTIC Cancer Network Directory, plus an online map Journal articles and position papers - 12 Declarations - 2 Projects - cancer registry mapping Grants - Beginning investigator catalytic grants (BIG Cat), partner NCI (USA) +20 beneficiaries. What was learned: Through coordinated and concerted efforts, relevant stakeholders who can influence and improve cancer care on the continent through collaboration, research and training, AORTIC is a continental networking hub spanning the African continent of more than 13,000 contacts and is a major instrument of change in effective control of cancer in Africa.

Informativeness of patient initial reports of adverse drug reactions. Can it be improved by a pharmacovigilance centre?

PURPOSE

Little is known about the informativeness of initial patient reports before they are reviewed by a pharmacovigilance centre (PVC). We aim to describe the patterns of patient adverse drug reaction (ADR) reporting in France and estimate the contribution of a review by a PVC assessor on the informativeness of these reports.

METHODS

A retrospective study was conducted on patient reports between July 2011 and July 2015. Informativeness of 16 key elements of information (including drug start and end date, duration of treatment, time to onset and duration of the ADR, outcome, medical history and concomitant medication) was assessed in initial reports before and after review by a pharmacovigilance assessor.

RESULTS

Overall, 240 reports concerning 522 ADR and involving 278 drugs were reported over this 4-year period. Mean number of available key elements of information in initial reports was increased from 11/16 to 15/16 after review of reports by the PVC. Time to onset and duration of the ADR were respectively available in only 51 and 58% of the reports before review compared to 83 and 90% after review. Medical history and concomitant medication were missing in 75% of the initial reports compared to less than 30% of the reports after review. Contacting the reporter enabled an increase of informativeness of most elements of information for more than 90% of the reports.

CONCLUSION

Patient reports often need to be completed on key elements of information that are required to assess reports. Both upstream education of patients and downstream intervention of a pharmacovigilance assessor to complete missing information could help to enhance the informativeness of such reports.

Impact of High-intensity Intermittent and Moderate-intensity Continuous Exercise on Autonomic Modulation in Young Men

The aim of this study was to compare heart rate variability (HRV) recovery after two iso-volume (5 km) exercises performed at different intensities. 14 subjects volunteered (25.17±5.08 years; 74.7±6.28 kg; 175±0.05 cm; 59.56±5.15 mL·kg(-1)·min(-1)) and after determination of peak oxygen uptake (VO2Peak) and the speed associated with VO2Peak (sVO2Peak), the subjects completed 2 random experimental trials: high-intensity exercise (HIE - 1:1 at 100% sVO2Peak), and moderate-intensity continuous exercise (MIE - 70% sVO2Peak). HRV and RR intervals were monitored before, during and after the exercise sessions together with, the HRV analysis in the frequency domains (high-frequency - HF: 0.15 to 0.4 Hz and low-frequency - LF: 0.04 to 0.15 Hz components) and the ratio between them (LF/HF). Statistical analysis comparisons between moments and between HIE and MIE were performed using a mixed model. Both exercise sessions modified LFlog, HFlog, and LF/HF (F=16.54, F=19.32 and F=5.17, p<0.05, respectively). A group effect was also found for LFlog (F=23.91, p<0.05), and HFlog (F=57.55, p< 0.05). LF/HF returned to resting value 15 min after MIE exercise and 20 min after HIE exercise. This means that the heavy domain (aerobic and anaerobic threshold) induces dissimilar autonomic modification in physically active subjects. Both HIE and MIE modify HRV, and generally HIE delays parasympathetic autonomic modulation recovery after iso-volume exercise.

Cardioprotective Properties of Aerobic and Resistance Training Against Myocardial Infarction

We evaluated the effects of aerobic and resistance exercise training on ventricular morphometry and function, physical capacity, autonomic function, as well as on ventricular inflammatory status in trained rats prior to myocardial infarction. Male Wistar rats were divided into the following groups: sedentary+Sham, sedentary+myocardial infarction, aerobic trained+myocardial infarction, and resistance trained+myocardial infarction. Sham and myocardial infarction were performed after training periods. In the days following the surgeries, evaluations were performed. Aerobic training prevents aerobic (to a greater extent) and resistance capacity impairments, ventricular dysfunction, baroreflex sensitivity and autonomic disorders (vagal tonus decrease and sympathetic tonus increase) triggered by myocardial infarction. Resistance training was able to prevent negative changes to aerobic and resistance capacity (to a greater extent) but not to ventricular dysfunction, and it prevented cardiovascular sympathetic increments. Additionally, both types of training reduced left ventricle inflammatory cytokine concentration. Our results suggest that aerobic and, for the first time, dynamic resistance training were able to reduce sympathetic tonus to the heart and vessels, as well as preventing the increase in pro-inflammatory cytokine concentrations in the left ventricle of trained groups. These data emphasizes the positive effects of aerobic and dynamic resistance training on the prevention of the negative changes triggered by myocardial infarction.

Correlations between traits in soybean (Glycine max L.) naturally infected with Asian rust (Phakopsora pachyrhizi)

Soybean (Glycine max L.)-breeding programs aim to develop cultivars with high grain yields and high tolerance to Asian soybean rust (Phakopsora pachyrhizi). Considering that the traits targeted for breeding are mainly quantitative in nature, knowledge of associations between traits allows the breeder to formulate indirect selection strategies. In this study, we investigated phenotypic, genotypic, and environmental correlations between the agronomic traits of soybean plants naturally infected with P. pachyrhizi, and identified agronomic traits that would be useful in indirectly selecting soybean genotypes for high yields. The study was conducted on the Capim Branco Farm, Uberlândia, Brazil, with 15 soybean genotypes, which were cultivated in a completely randomized block design with four replications. Fourteen phenotypic traits were evaluated using the GENES software. The phenotypic and genotypic correlations were positive and of a high magnitude between the total number of pods and the number of pods with two or three grains, indicating that the total number of pods is a useful trait for the indirect selection of soybean genotypes for high grain yields. Strong environmental correlations were found between plant height at blooming and maturity and grain yield and yield components.

Exercise training prevents increased intraocular pressure and sympathetic vascular modulation in an experimental model of metabolic syndrome

The present study aimed to study the effects of exercise training (ET) performed by rats on a 10-week high-fructose diet on metabolic, hemodynamic, and autonomic changes, as well as intraocular pressure (IOP). Male Wistar rats receiving fructose overload in drinking water (100 g/L) were concomitantly trained on a treadmill for 10 weeks (FT group) or kept sedentary (F group), and a control group (C) was kept in normal laboratory conditions. The metabolic evaluation comprised the Lee index, glycemia, and insulin tolerance test (KITT). Arterial pressure (AP) was measured directly, and systolic AP variability was performed to determine peripheral autonomic modulation. ET attenuated impaired metabolic parameters, AP, IOP, and ocular perfusion pressure (OPP) induced by fructose overload (FT vs F). The increase in peripheral sympathetic modulation in F rats, demonstrated by systolic AP variance and low frequency (LF) band (F: 37±2, 6.6±0.3 vs C: 26±3, 3.6±0.5 mmHg²), was prevented by ET (FT: 29±3, 3.4±0.7 mmHg²). Positive correlations were found between the LF band and right IOP (r=0.57, P=0.01) and left IOP (r=0.64, P=0.003). Negative correlations were noted between KITT values and right IOP (r=-0.55, P=0.01) and left IOP (r=-0.62, P=0.005). ET in rats effectively prevented metabolic abnormalities and AP and IOP increases promoted by a high-fructose diet. In addition, ocular benefits triggered by exercise training were associated with peripheral autonomic improvement.

Investigation of a spatiotemporal cluster of verotoxin-producing Escherichia coli O157 infections in eastern England in 2007

An outbreak of verotoxin-producing Escherichia coli O157 (VTEC O157) infections linked to an open farm occurred in eastern England in April and May 2007. This paper describes the investigation and highlights the importance of multidisciplinary collaboration for successful control of such outbreaks. There was a temporal cluster of 12 confirmed symptomatic cases of VTEC O157 and one asymptomatic carrier, from five families. The investigation revealed that four of these cases formed part of an outbreak involving two families who visited an open farm. The phenotypic and genotypic characteristics of the isolates from the two families and the putative farm animal contacts were indistinguishable, indicating that the animals were the source of the primary infections. No epidemiological link could be established between the remaining three families affected and the open farm or people having visited the farm. Control measures included improved hand washing facilities on the farm, information for visitors and staff, restricted access and suspended petting and feeding of animals, and thorough cleaning and disinfection of affected areas.

Investigation of a spatiotemporal cluster of verotoxin-producing Escherichia coli O157 infections in eastern England in 2007

An outbreak of verotoxin-producing Escherichia coli O157 (VTEC O157) infections linked to an open farm occurred in eastern England in April and May 2007. This paper describes the investigation and highlights the importance of multidisciplinary collaboration for successful control of such outbreaks. There was a temporal cluster of 12 confirmed symptomatic cases of VTEC O157 and one asymptomatic carrier, from five families. The investigation revealed that four of these cases formed part of an outbreak involving two families who visited an open farm. The phenotypic and genotypic characteristics of the isolates from the two families and the putative farm animal contacts were indistinguishable, indicating that the animals were the source of the primary infections. No epidemiological link could be established between the remaining three families affected and the open farm or people having visited the farm. Control measures included improved hand washing facilities on the farm, information for visitors and staff, restricted access and suspended petting and feeding of animals, and thorough cleaning and disinfection of affected areas.

Schistosoma mansoni: a rare cause of tubal infection

S. haematobium is an important cause of urinary schistosomiasis, and symptomatic female genital infection is a common gynecological finding in areas where S. haematobium is prevalent. On the other hand, genital manifestations of intestinal schistosomas as S. mansoni are not frequent or are misdiagnosed. A case of a 40-year-old woman with abnormal uterine bleeding and asymptomatic tubal infection by S. mansoni identified in histological examination is presented.

Routine intracranial pressure monitoring in acute coma

BACKGROUND

Studies in traumatic encephalopathy first led to the insight that the damage seen was not just due to direct consequences of the primary injury. A significant, and potentially preventable, contribution to the overall morbidity arose from secondary hypoxic-ischaemic damage. Brain swelling accompanied by raised intracranial pressure (ICP) resulted in inadequate cerebral perfusion with well-oxygenated blood. Detection of raised ICP could be useful in alerting clinicians to the need to improve cerebral perfusion, with consequent reductions in brain injury.

OBJECTIVES

To determine whether routine ICP monitoring in all acute cases of severe coma reduces the risk of all-cause mortality or severe disability at final follow-up.

SEARCH STRATEGY

We searched the Cochrane Injuries Group's Specialised Register (searched 7 April 2009), CENTRAL (The Cochrane Library 2009, Issue 1), MEDLINE 1950 to March week 4 2009, EMBASE 1980 to week 14 March 2009, CINAHL 1982 to March 2009, ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED) 1970 to March 2009, Conference Proceedings Citation Index- Science (CPCI-S) 1990 to March 2009, PubMed (searched 7 April 2009, limit; added in last 6 months). The searches were last updated in April 2009.

SELECTION CRITERIA

All randomised controlled studies of real-time ICP monitoring by invasive or semi-invasive means in acute coma (traumatic or non-traumatic aetiology) versus no ICP monitoring (that is, clinical assessment of ICP).

DATA COLLECTION AND ANALYSIS

Primary outcome measures were all-cause mortality and severe disability at the end of the follow-up period.

MAIN RESULTS

No studies meeting the selection criteria have been identified to date.

AUTHORS' CONCLUSIONS

There are no data from randomised controlled trials that can clarify the role of ICP monitoring in acute coma.

Is intravenous urography necessary in the assessment of renal duplex system in children?

OBJECTIVE

Partial or complete duplication of the renal tract may be an incidental finding or may be associated with significant pathology. Accurate assessment is not always easy. This retrospective review was undertaken to determine whether intravenous urography (IVU) in combination with a DMSA renal scan provides significant additional information.

PATIENTS AND METHODS

Eighteen patients referred to our imaging department with a provisional diagnosis on ultrasound of renal tract duplication during a three year period were identified by searching the radiological computer files. The presenting features were urinary infection (13), abdominal pain (3) and abnormal antenatal sonography (2).

RESULTS

Four patients were found not to have renal duplication. There was concordance between the IVU and DMSA scan in seven. Additional clinically relevant information was obtained in three cases. A false negative result from the DMSA scan was found in four children and a false positive result in three.

CONCLUSION

In a significant number of cases of possible renal tract duplication, additional relevant information can be obtained from an IVU. Patient distress is minimised by combining the IVU and DMSA in one single episode of venous access. Review of the radiological images during the investigation allows minimisation of radiation dosage.

Metformin influences cardiomyocyte cell death by pathways that are dependent and independent of caspase-3

AIMS/HYPOTHESIS

Metformin has been shown to increase fatty acid oxidation, an effect mediated by AMP activated protein kinase (AMPK). We hypothesised that metformin could prevent both caspase-3 activation and apoptosis when induced by palmitic acid.

MATERIALS AND METHODS

Cardiomyocytes were incubated with 1 mmol/l palmitic acid, in the absence or presence of metformin (1-5 mmol/l). Following 1 to 16 h, cell damage was evaluated by measuring lactate dehydrogenase released into the incubation medium, and Hoechst staining. To investigate the mechanism of metformin's effect on cardiomyocytes, substrate utilisation and phosphorylation of AMPK and acetyl-CoA carboxylase were measured. Intracellular mediators of apoptosis were also evaluated.

RESULTS

Incubation of myocytes with palmitic acid for 16 h increased apoptosis, an effect that was partly blunted by 1 and 2 mmol/l metformin. This beneficial effect of metformin was associated with increased AMPK phosphorylation, palmitic acid oxidation and suppression of high-fat-induced increases in (1) long chain base biosynthesis protein 1 levels, (2) ceramide levels, and (3) caspase-3 activity. Unexpectedly, 5 mmol/l metformin dramatically increased apoptosis in myocytes incubated with high fat. This effect was associated with a robust increase in glycolysis, lactate accumulation, and a significant drop of pH in the myocyte incubation medium.

CONCLUSIONS/INTERPRETATION

Our study demonstrates that metformin reduces high-fat-induced cardiac cell death, probably through inhibition of ceramide synthesis. However, at high concentrations, metformin causes proton and lactate accumulation, leading to cell damage that is independent of caspase-3.

Diagnosis of respiratory bronchiolitis associated interstitial lung disease

BACKGROUND

Respiratory Bronchiolitis (RB), described by Niewoehner et al in 1974, is a common finding in heavy smokers and is characterised by the presence of pigmented macrophages within respiratory bronchioles and adjacent alveoli. In the 1980s, Myers et al described RB associated with interstitial lung disease (RBILD), which is a rare entity expressed as an amplified respiratory bronchiolitis in response to cigarette smoke.

METHODS

The authors studied a group of 8 patients with biopsy-proven RBILD diagnosed within the last five years, and assessed epidemiological data, clinical and imaging features, lung function tests, bronchoalveolar lavage findings, therapeutic approaches and clinical evolution.

RESULTS AND CONCLUSIONS

The most difficult differential diagnosis is between RBILD and Desquamative Interstitial Pneumonia (DIP), which seems to suggest that these disorders are either end of the same spectrum, although the authors claim that there are some clinical, morphological and prognostic distinctions. The diagnosis of RBILD requires an appropriate clinical setting (including smoking habits), characteristic image findings (like ground glass shadowing and centrilobular nodules), and Bronchoalveolar Lavage (BAL) data to exclude other diagnosis. Pathological confirmation may also be important, not only to exclude more adverse interstitial lung disease, such as idiopathic pulmonary fibrosis, but also, as in the eight cases presented, to illustrate some specific features such as the prevalence of lymphocytosis in BAL.

Lack of in vivo effect of vanadium on GLUT4 translocation in white adipose tissue of streptozotocin-diabetic rats

Vanadium treatment, in vivo, corrects the severe hyperglycemia observed in streptozotocin (STZ)-diabetic rats. A number of metabolic effects of vanadium have been demonstrated in vitro and might contribute importantly to normalization of glucose homeostasis. However, many in vitro effects of vanadium occur at concentrations substantially higher than those achieved in vivo. Effects of vanadium on white adipose tissue have been particularly well characterized in vitro. To examine the relationship between in vitro and in vivo actions of vanadium, we examined the effects of vanadium treatment on acute glucose tolerance and adipose tissue GLUT4 control in vivo. In agreement with previous studies, vanadium treatment of STZ-diabetic rats restored normoglycemia with no appreciable restoration of insulin secretion. GLUT4 expression in white adipose tissue was reduced by 22% in STZ-diabetic rats compared with controls. Vanadium treatment did not significantly alter GLUT4 expression in controls, but completely restored normal expression levels in STZ-diabetic rats. In overnight-fasted control animals, GLUT4 translocation to the plasma membrane (PM) was maximally elevated (by 50%) in adipose tissue within 5 to 10 minutes after an intravenous (IV) glucose challenge. No glucose-induced translocation of GLUT4 was detected in diabetic rats, and peak PM GLUT4 content was 40% lower than in controls. Vanadium treatment did not increase peak PM GLUT4 content in either control or diabetic animals in response to a glucose load. Finally, the suppression of whole-body acute glucose tolerance in diabetic animals was only partially normalized by vanadium treatment. We conclude: (1) that concentrations of vanadium effective for maintaining normoglycemia in vivo (typically below 30 micromol/L) promote normal GLUT4 expression, but do not influence the subcellular localization of GLUT4 in white adipose tissue and (2) that in vivo effects of vanadium may not necessarily reflect the actions observed in vitro at supraphysiologic concentrations.

Hypertrophied rat hearts are less responsive to the metabolic and functional effects of insulin

We determined the effect of insulin on the fate of glucose and contractile function in isolated working hypertrophied hearts from rats with an aortic constriction (n = 27) and control hearts from sham-operated rats (n = 27). Insulin increased glycolysis and glycogen in control and hypertrophied hearts. The change in glycogen was brought about by increased glycogen synthesis and decreased glycogenolysis in both groups. However, the magnitude of change in glycolysis, glycogen synthesis, and glycogenolysis caused by insulin was lower in hypertrophied hearts than in control hearts. Insulin also increased glucose oxidation and contractile function in control hearts but not in hypertrophied hearts. Protein content of glucose transporters, protein kinase B, and phosphatidylinositol 3-kinase was not different between the two groups. Thus hypertrophied hearts are less responsive to the metabolic and functional effects of insulin. The reduced responsiveness involves multiple aspects of glucose metabolism, including glycolysis, glucose oxidation, and glycogen metabolism. The absence of changes in content of key regulatory molecules indicates that other sites, pathways, or factors regulating glucose utilization are responsible for these findings.

Metabolism of VLDL is increased in streptozotocin-induced diabetic rat hearts

In streptozotocin (STZ)-induced diabetic rats, we previously showed an increased heparin-releasable (luminal) lipoprotein lipase (LPL) activity from perfused hearts. To study the effect of this enlarged LPL pool on triglyceride (TG)-rich lipoproteins, we examined the metabolism of very-low-density lipoprotein (VLDL) perfused through control and diabetic hearts. Diabetic rats had elevated TG levels compared with control. However, fasting for 16 h abolished this difference. When the plasma lipoprotein fraction of density <1.006 g/ml from fasted control and diabetic rats was incubated in vitro with purified bovine or rat LPL, VLDL from diabetic animals was hydrolyzed as proficiently as VLDL from control animals. Post-heparin plasma lipolytic activity was comparable in control and diabetic animals. However, perfusion of control and diabetic rats with heparinase indicated that diabetic hearts had larger amounts of LPL bound to heparan sulfate proteoglycan-binding sites. [(3)H]VLDL obtained from control rats, when recirculated through the isolated heart, disappeared at a significantly faster rate from diabetic than from control rat hearts. This increased VLDL-TG hydrolysis was essentially abolished by prior perfusion of the diabetic heart with heparin, implicating LPL in this process. These findings suggest that the enlarged LPL pool in the diabetic heart is present at a functionally relevant location (at the capillary lumen) and is capable of hydrolyzing VLDL. This could increase the delivery of free fatty acid to the heart, and the resultant metabolic changes could induce the subsequent cardiomyopathy that is observed in the chronic diabetic rat.

Distinct glucose lowering and beta cell protective effects of vanadium and food restriction in streptozotocin-diabetes

Vanadium is an oral insulin-mimetic agent that diminishes hyperglycemia, improves beta-cell insulin store and secretory function, and can reverse the diabetic state chronically after withdrawal from treatment. As food restriction has been reported to enhance insulin sensitivity and reduce insulin demand, we assessed the contribution of a reduced food intake to the glucose lowering and beta-cell protective effects of vanadium. Streptozotocin (STZ)-diabetic rats were untreated (D) or administered vanadyl sulfate in the drinking water (DT) at one week prior to and for 5 weeks following the administration of STZ. An additional group was pair-fed (DP) with an equal amount of food as that consumed by the DT group. Shortly after the induction of diabetes, hyperglycemic D rats demonstrated a significant rise in plasma insulin to levels that initially exceeded that of the controls. This was followed by a steady reduction over several weeks, suggesting a gradual depletion of functional beta-cells. Both vanadium treatment and pair-feeding abolished the insulin hypersecretory response following STZ administration. Glucose lowering was enhanced in DT animals when administered higher concentrations of vanadium, despite no further reduction in food intake, and all DT animals (10/10) were normoglycemic by 5 weeks. Mean pancreatic insulin content in DT rats was improved fourfold and was associated with a greater number of granulated beta-cells. Conversely, food restriction only modestly improved glycemia and the pancreatic insulin store and, unlike DT, DP rats remained highly glucose-intolerant. At 5 weeks of diabetes, fed circulating glucose and insulin levels were strongly correlated (P=0.0002) in the D and DP groups, supporting the notion that glucose lowering with food restriction is dependent on improved plasma insulin levels. A separate correlation was observed in DT animals within a lower range of plasma insulin, suggesting that vanadium, unlike food restriction, reduced plasma glucose by enhancing insulin sensitivity. Thus, vanadium preserves beta-cells in STZ-diabetes at least partially by abolishing the insulin hypersecretory response and the eventual exhaustion of residual insulin stores following a moderate dose of STZ. This property of vanadium would appear to be useful in the treatment of prediabetic and newly diagnosed insulin-dependent diabetes mellitus.

Multiple-site phosphorylation of the 280 kDa isoform of acetyl-CoA carboxylase in rat cardiac myocytes: evidence that cAMP-dependent protein kinase mediates effects of beta-adrenergic stimulation

Two major forms of mammalian acetyl-CoA carboxylase (EC 6.4.1.2), ACC-alpha and ACC-beta, have been described and the sequences of the isoforms deduced. ACC-beta is the predominant isoform expressed in heart and skeletal muscles, in which a major role of malonyl-CoA is probably to regulate fatty acid beta-oxidation. The regulatory properties of ACC-beta are incompletely defined but it is known that some cellular stresses lead to inhibition in parallel with the activation of AMP-activated protein kinase (AMP-PK). Here we examine the phosphorylation state of ACC-beta within intact rat cardiac ventricular myocytes. Treatment of myocytes with the beta-adrenergic agonist isoprenaline (isoproterenol) led to increased ACC-beta phosphorylation that was maximal within 2 min and with 50 nM agonist. Effects of isoprenaline were revealed by the incorporation of 32P into ACC in cells incubated with [32P]Pi and also by a marked decrease (approx. 80%) in subsequent phosphorylation in vitro with cAMP-dependent protein kinase (PKA). Analysis of tryptic phosphopeptides revealed that ACC-beta was phosphorylated at multiple sites by incubation in vitro with PKA or AMP-PK. Treatment of myocytes with isoprenaline affected all the major phosphorylation sites of ACC-beta that were recognized in vitro by purified PKA, so that subsequent phosphorylation in vitro was greatly diminished after cell stimulation. beta-Adrenergic stimulation led to decreases in cellular malonyl-CoA concentrations but no changes in kinetic properties of ACC were detected after cell homogenization and partial purification of proteins. The results suggest that: (1) ACC-beta is rapidly phosphorylated at multiple sites within intact cardiac ventricular myocytes after beta-adrenergic stimulation, (2) ACC-beta is phosphorylated in vitro by PKA and AMP-PK at multiple sites, including at least one site accessible to each kinase, as well as kinase-selective sites, and (3) PKA is a physiologically significant ACC-beta kinase.

Localization of lipoprotein lipase in the diabetic heart: regulation by acute changes in insulin

Vascular endothelium-bound lipoprotein lipase (LPL) is rate limiting for free fatty acid (FFA) transport into tissues. In streptozotocin (STZ)-diabetic rats, we have previously demonstrated an increased heparin-releasable LPL activity from perfused hearts. Because heparin can traverse the endothelial barrier, conventional Langendorff retrograde perfusion of the heart with heparin could release LPL from both the capillary luminal and abluminal surfaces. To determine the precise location of the augmented LPL, a modified Langendorff retrograde perfusion was used to isolate the enzyme at the coronary lumen from that in the interstitial effluent. In response to heparin, a 4-fold increase in LPL activity and protein mass was observed in the coronary perfusate after 2 weeks of STZ diabetes. Release of LPL activity into the interstitial fluid of control hearts was slow but progressive, whereas in diabetic hearts, peak enzyme activity was observed within 1 to 2 minutes after heparin, followed by a gradual decline. Immunohistochemical studies of myocardial sections confirmed that the augmented LPL in diabetic hearts was mainly localized at the capillary endothelium. To study the acute effects of insulin on endothelial LPL activity, we examined rat hearts at various times after the onset of hyperglycemia. An increased heparin-releasable LPL activity in diabetic rats was demonstrated shortly (6 to 24 hours) after STZ injection or after withdrawal from exogenous insulin. Heparin-releasable coronary LPL activity was also increased after an overnight fast. These studies indicate that the intravascular heparin-releasable fraction of cardiac LPL activity is acutely regulated by short-term changes in insulin rather than glucose. Thus, during short periods (hours) of hypoinsulinemia, increased LPL activity at the capillary endothelium can increase the delivery of FFAs to the heart. The resultant metabolic changes could induce the subsequent cardiomyopathy that is observed in the chronic diabetic rat.

Proatherogenic and antiatherogenic effects of probucol and phytosterols in apolipoprotein E-deficient mice: possible mechanisms of action

BACKGROUND

The effects of probucol and a phytosterol mixture (FCP-3PI) on atherosclerotic lesion formation, plasma lipoproteins, hepatic and lipoprotein lipase activities, antioxidant enzyme activities, and plasma fibrinogen were investigated in apolipoprotein E-knockout (apoE-KO) mice.

METHODS AND RESULTS

Three groups of 8 mice were fed a diet containing 9% (wt/wt) fat (controls) or the foregoing diet supplemented with either 1% (wt/wt) probucol (the probucol group) or 2% (wt/wt) FCP-3PI (the FCP-3PI group) for 20 weeks. Compared with controls, atherosclerotic lesion size was 3 times greater in the probucol group, whereas it was decreased by half in the FCP-3PI group. Probucol treatment resulted in high plasma probucol concentrations, which correlated (r=0.69) with the lesion area. HDL cholesterol was reduced (>75%) in the probucol group and slightly increased (14%) in the FCP-3PI-treated group. Postheparin lipoprotein lipase (LPL) activity was significantly reduced in both treatment groups, but only FCP-3PI significantly decreased hepatic lipase activity. Plasma fibrinogen was increased 42% by probucol and decreased 19% by FCP-3PI relative to controls. Probucol significantly increased plasma glutathione reductase, glutathione peroxidase, and superoxide dismutase activities (P<0.05). In contrast to findings in apoE-KO mice, there was no probucol-induced atherosclerosis in their wild-type counterparts fed the same dose for the same period of time.

CONCLUSIONS

Antiatherogenic activity of FCP-3PI in apoE-KO mice is associated with an increase in HDL cholesterol concentration along with decreases in hepatic lipase activity and plasma fibrinogen concentrations. Proatherogenic effects of probucol may be related to increased plasma fibrinogen, decreased HDL cholesterol concentrations along with decreased LPL activity, or its direct "toxicity" due to very high plasma concentration. Our studies demonstrate that the antioxidant and cholesterol-lowering properties of probucol do not prevent atherogenesis in this particular animal model.