EPCT-16. A PHASE IB STUDY OF PTC596 IN CHILDREN WITH NEWLY DIAGNOSED DIFFUSE INTRINSIC PONTINE GLIOMA AND HIGH GRADE GLIOMA

BACKGROUND

BMI-1 is highly expressed in DIPG. Downregulation leads to inhibition of cell proliferation, cell cycle signaling, self-renewal, telomerase expression, activity, and suppression of DIPG cell migration. Targeted inhibition of BMI-1 sensitizes DIPG cells to radiation and drug-induced DNA damage. PTC596 (formulated by PTC Therapeutics, Inc.) is a novel, orally available drug that inhibits microtubule polymerization, resulting in G2/M cell cycle arrest and post-translational modification of BMI-1 protein and reduced BMI-1 protein levels. OBJECTIVES: To estimate the maximum tolerated dose and describe dose limiting toxicities, pharmacokinetics and pharmacodynamics of PTC596 in children 3–21 years of age with newly diagnosed diffuse intrinsic pontine glioma and high-grade gliomas.

METHODS

PTC596 is administered twice per week orally during radiotherapy and as maintenance for up to two years. The starting dose of PTC596 was 200 mg/m², with a subsequent dose level of 260mg/m²/dose. Pharmacokinetics are performed in Cycles 1 and 2.

RESULTS

This study is currently ongoing. Nine patients (7 with DIPG, 2 with HGG), 8 evaluable, have been enrolled. At dose level 1, 200 mg/m², three evaluable patients were enrolled and experienced no DLTs. At dose level 2, among 5 evaluable patients, 2 experienced dose-limiting grade 4 neutropenia. PTC596 has been otherwise well tolerated. Five patients remain in Cycles 2–11.

CONCLUSION

This phase I trial is ongoing. PTC596 is tolerable at dose level 1. We are amending the protocol to introduce tablets that can be dissolved in liquid to allow enrollment of younger patients and those unable to swallow whole tablets.

EPCT-19. A PHASE I STUDY OF RIBOCICLIB AND EVEROLIMUS FOLLOWING RADIATION THERAPY IN CHILDREN WITH NEWLY DIAGNOSED NON-BIOPSIED DIFFUSE PONTINE GLIOMAS (DIPG) AND RB+ BIOPSIED DIPG AND HIGH GRADE GLIOMAS (HGG)

Genomic aberrations in the cell cycle and mTOR pathways have been reported in diffuse pontine gliomas (DIPG) and high-grade gliomas (HGG). Dual inhibition of CDK4/6 (ribociclib) and mTOR (everolimus) has strong biologic rationale, non-overlapping single-agent toxicities, and adult clinical experience. The maximum tolerated dose (MTD) and/or recommended phase two dose (RP2D) of ribociclib and everolimus administered during maintenance therapy following radiotherapy was determined in the phase I study as a rolling 6 design. Ribociclib and everolimus were administered once daily for 21 days and 28 days, respectively starting two-four weeks post completion of radiotherapy. All HGG patients and any DIPG patient who had undergone biopsy were screened for RB protein by immunohistochemistry. Eighteen eligible patients enrolled (median age 8 years; range: 2–18). Six patients enrolled at dose levels 1,2, and 3 without dose limiting toxicities (DLT). Currently, five patients are enrolled at dose level 3 expansion cohort. The median number of cycles are 4.5 (range: 1–20+). Among the expansion cohort, one dose limiting toxicity included a grade 3 infection and one patient required a dose reduction in course 3 due to grade 3 ALT and grade 4 hypokalemia. The most common grade 3/4 adverse events included neutropenia. Preliminary pharmacokinetic studies on 12 patients suggest an impact of ribociclib on everolimus pharmacokinetics. The MTD/RP2D of ribociclib and everolimus following radiotherapy in newly diagnosed DIPG and HGG is anticipated to be 170 mg/m2/day x 21 days and 1.5 mg/ m2/day every 28 days which is equivalent to the adult RP2D.

PATH-13. CHARACTERIZING TEMPORAL GENOMIC HETEROGENEITY IN PEDIATRIC LOW-GRADE GLIOMAS

BACKGROUND

Recent discoveries have provided valuable insight into the genomic landscape of pediatric low-grade gliomas (LGGs) at diagnosis, facilitating molecularly targeted treatment. However, little is known about their temporal and therapy-related genomic heterogeneity. An adequate understanding of the evolution of pediatric LGGs’ genomic profiles over time is critically important in guiding decisions about targeted therapeutics and diagnostic biopsy at recurrence.

METHODS

Fluorescence in situ hybridization, mutation-specific immunohistochemistry, exome analyses, and/or targeted sequencing were performed on paired tumor samples from diagnostic and subsequent surgeries.

RESULTS

Ninety-four tumor samples from 45 patients (41 with two specimens, four with three specimens) from three institutions underwent testing. Conservation of BRAF fusion, BRAFV600E mutation, and FGFR1 rearrangement status was observed in 100%, 98%, and 96% of paired specimens, respectively. No loss or gain of IDH1 mutations or NTRK2, MYB, or MYBL1 rearrangements were detected over time. Histologic diagnosis remained the same in all tumors, with no acquired H3K27M mutations or malignant transformation. Changes in CDKN2A deletion status occurred in 10 patients (40%), with acquisition of CDKN2A deletion in seven (including three who received chemotherapy [two with temozolomide] and one who received radiation) and loss in three (including one who received targeted therapy and radiation). A trend toward shorter time to progression was observed among patients with acquired CDKN2A deletions compared to patients without acquisition of this alteration (median: 5.5 versus 14.0 months [p=0.078]).

CONCLUSIONS

Most targetable genetic aberrations in pediatric LGGs, including BRAF alterations, are conserved at recurrence and following chemotherapy or radiation. However, changes in CDKN2A deletion status over time were demonstrated. Acquisition of CDKN2A deletion may define a higher risk subgroup of pediatric LGGs with a poorer prognosis. Given the potential for targeted therapies for tumors harboring CDKN2A deletions, biopsy at recurrence may be indicated in certain patients, especially those with rapid progression.

The OMA orthology database in 2018: retrieving evolutionary relationships among all domains of life through richer web and programmatic interfaces

The Orthologous Matrix (OMA) is a leading resource to relate genes across many species from all of life. In this update paper, we review the recent algorithmic improvements in the OMA pipeline, describe increases in species coverage (particularly in plants and early-branching eukaryotes) and introduce several new features in the OMA web browser. Notable improvements include: (i) a scalable, interactive viewer for hierarchical orthologous groups; (ii) protein domain annotations and domain-based links between orthologous groups; (iii) functionality to retrieve phylogenetic marker genes for a subset of species of interest; (iv) a new synteny dot plot viewer; and (v) an overhaul of the programmatic access (REST API and semantic web), which will facilitate incorporation of OMA analyses in computational pipelines and integration with other bioinformatic resources. OMA can be freely accessed at https://omabrowser.org.

Morbidity and cost burden of prenatal myelomeningocele repair

OBJECTIVE

This study compared the morbidities and financial burden associated with prenatal open myelomeningocele repair versus postnatal repair.

MATERIALS AND METHODS

The retrospective study cohort included 23 mother-infant dyads undergoing prenatal repair and 30 with postnatal repair. Financial, demographic, and medical information were obtained for mother-infant dyads from each infant's birth through the first year of life.

RESULTS

Infants in the prenatal repair group were significantly affected by sequelae of prematurity, including apnea, bronchopulmonary dysplasia, and retinopathy of prematurity. Importantly, fewer of these infants required ventriculoperitoneal shunt procedures and the overall improved composite outcome of shunting or death. Infants in the postnatal repair group required more hospital readmissions in the first year of life. Financial costs for mother-infant dyads in the prenatal repair group were higher, driven by the length of stay in the neonatal intensive care unit and maternal hospital admissions. Kaplan-Meier curves analyzing the relative contributions of the length of stay and total charges in the population were constructed. The maternal contribution was markedly different between groups due to postoperative hospitalization, readmission, and close fetal surveillance required. Though these differences did not reach statistical significance, it highlights an important burden on families and the medical system.

CONCLUSIONS

This is the first study to report the contributions of prematurity in relation to maternal and infant morbidity and financial costs. The benefits of prenatal myelomeningocele repair include lower risk for ventriculoperitoneal shunting and fewer hospital readmissions. The risk of preterm birth and its neonatal sequelae continue to be a significant burden.

CT pulmonary angiography in lower limb arthroplasty

Aims

The aims of this study were to determine the indications and frequency of ordering a CT pulmonary angiography (CTPA) following primary arthroplasty of the hip and knee, and to determine the number of positive scans in these patients, the location of emboli and the outcome for patients undergoing CTPA.

Patients and Methods

We analyzed the use of CTPA, as an inpatient and up to 90 days as an outpatient, in a cohort of patients and reviewed the medical records and imaging for each patient undergoing CTPA.

Results

Out of 11 249 patients, scans were requested in 229 (2.04%) and 86 (38%) were positive. No patient undergoing CTPA died within 90 days. The rate of mortality from pulmonary embolism (PE) overall was 0.08%. CTPA was performed twice as often following total knee arthroplasty (TKA) compared with total hip arthroplasty (THA), and when performed was twice as likely to be positive. Hypoxia was the main indication for a scan, being the indication in 149 scans (65%); and in 23% (11 of 47), the PE was peripheral and unilateral. Three patients suffered complications resulting from therapeutic anticoagulation for possible PE, two of whom had a negative CTPA.

Conclusion

CTPA is more likely to be performed following TKA compared with THA. Hypoxia was the main presenting feature of PE. A quarter of PEs which were diagnosed were unilateral and peripheral. Further study may indicate which patients who have a PE after lower limb arthroplasty require treatment, and which can avoid the complications associated with anticoagulation. Cite this article: Bone Joint J 2018;100-B:938–44.

Characterizing temporal genomic heterogeneity in pediatric high-grade gliomas

Pediatric high-grade gliomas (pHGGs) are aggressive neoplasms representing approximately 20% of brain tumors in children. Current therapies offer limited disease control, and patients have a poor prognosis. Empiric use of targeted therapy, especially at progression, is increasingly practiced despite a paucity of data regarding temporal and therapy-driven genomic evolution in pHGGs. To study the genetic landscape of pHGGs at recurrence, we performed whole exome and methylation analyses on matched primary and recurrent pHGGs from 16 patients. Tumor mutational profiles identified three distinct subgroups. Group 1 (n = 7) harbored known hotspot mutations in Histone 3 (H3) (K27M or G34V) or IDH1 (H3/IDH1 mutants) and co-occurring TP53 or ACVR1 mutations in tumor pairs across the disease course. Group 2 (n = 7), H3/IDH1 wildtype tumor pairs, harbored novel mutations in chromatin modifiers (ZMYND11, EP300 n = 2), all associated with TP53 alterations, or had BRAF V600E mutations (n = 2) conserved across tumor pairs. Group 3 included 2 tumors with NF1 germline mutations. Pairs from primary and relapsed pHGG samples clustered within the same DNA methylation subgroup. ATRX mutations were clonal and retained in H3G34V and H3/IDH1 wildtype tumors, while different genetic alterations in this gene were observed at diagnosis and recurrence in IDH1 mutant tumors. Mutations in putative drug targets (EGFR, ERBB2, PDGFRA, PI3K) were not always shared between primary and recurrence samples, indicating evolution during progression. Our findings indicate that specific key driver mutations in pHGGs are conserved at recurrence and are prime targets for therapeutic development and clinical trials (e.g. H3 post-translational modifications, IDH1, BRAF V600E). Other actionable mutations are acquired or lost, indicating that re-biopsy at recurrence will provide better guidance for effective targeted therapy of pHGGs.

Tollip SNP rs5743899 modulates human airway epithelial responses to rhinovirus infection

BACKGROUND

Rhinovirus (RV) infection in asthma induces varying degrees of airway inflammation (e.g. neutrophils), but the underlying mechanisms remain unclear.

OBJECTIVE

The major goal was to determine the role of genetic variation [e.g. single nucleotide polymorphisms (SNPs)] of Toll-interacting protein (Tollip) in airway epithelial responses to RV in a type 2 cytokine milieu.

METHODS

DNA from blood of asthmatic and normal subjects was genotyped for Tollip SNP rs5743899 AA, AG and GG genotypes. Human tracheobronchial epithelial (HTBE) cells from donors without lung disease were cultured to determine pro-inflammatory and antiviral responses to IL-13 and RV16. Tollip knockout and wild-type mice were challenged with house dust mite (HDM) and infected with RV1B to determine lung inflammation and antiviral response.

RESULTS

Asthmatic subjects carrying the AG or GG genotype (AG/GG) compared with the AA genotype demonstrated greater airflow limitation. HTBE cells with AG/GG expressed less Tollip. Upon IL-13 and RV16 treatment, cells with AG/GG (vs. AA) produced more IL-8 and expressed less antiviral genes, which was coupled with increased NF-κB activity and decreased expression of LC3, a hallmark of the autophagic pathway. Tollip co-localized and interacted with LC3. Inhibition of autophagy decreased antiviral genes in IL-13- and RV16-treated cells. Upon HDM and RV1B, Tollip knockout (vs. wild-type) mice demonstrated higher levels of lung neutrophilic inflammation and viral load, but lower levels of antiviral gene expression.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data suggest that Tollip SNP rs5743899 may predict varying airway response to RV infection in asthma.

Spatial genomic heterogeneity in diffuse intrinsic pontine and midline high-grade glioma: implications for diagnostic biopsy and targeted therapeutics

Introduction

Diffuse intrinsic pontine glioma (DIPG) and midline high-grade glioma (mHGG) are lethal childhood brain tumors. Spatial genomic heterogeneity has been well-described in adult HGG but has not been comprehensively characterized in pediatric HGG. We performed whole exome sequencing on 38-matched primary, contiguous, and metastatic tumor sites from eight children with DIPG (n = 7) or mHGG (n = 1) collected using a unique MRI-guided autopsy protocol. Validation was performed using Sanger sequencing, Droplet Digital polymerase-chain reaction, immunohistochemistry, and fluorescent in-situ hybridization.

Results

Median age at diagnosis was 6.1 years (range: 2.9–23.3 years). Median overall survival was 13.2 months (range: 11.2–32.2 months). Contiguous tumor infiltration and distant metastases were observed in seven and six patients, respectively, including leptomeningeal dissemination in three DIPGs. Histopathological heterogeneity was evident in seven patients, including intra-pontine heterogeneity in two DIPGs, ranging from World Health Organization grade II to IV astrocytoma. We found conservation of heterozygous K27M mutations in H3F3A (n = 4) or HIST1H3B (n = 3) across all primary, contiguous, and metastatic tumor sites in all DIPGs. ACVR1 (n = 2), PIK3CA (n = 2), FGFR1 (n = 2), and MET (n = 1) were also intra-tumorally conserved. ACVR1 was co-mutated with HIST1H3B (n = 2). In contrast, PDGFRA amplification and mutation were spatially heterogeneous, as were mutations in BCOR (n = 1), ATRX (n = 2), and MYC (n = 1). TP53 aberrations (n = 3 patients) varied by type and location between primary and metastatic tumors sites but were intra-tumorally conserved.

Conclusion

Spatial conservation of prognostically-relevant and therapeutically-targetable somatic mutations in DIPG and mHGG contrasts the significant heterogeneity of driver mutations seen in adult HGG and supports uniform implementation of diagnostic biopsy in DIPG and mHGG to classify molecular risk groups and guide therapeutic strategy.

Electronic supplementary material

The online version of this article (doi:10.1186/s40478-015-0269-0) contains supplementary material, which is available to authorized users.

Pediatric tectal plate gliomas: a review of clinical outcomes, endocrinopathies, and neuropsychological sequelae

Pediatric tectal plate gliomas are indolent slow-growing gliomas that often present with increased intracranial pressure or incidentally on routine brain imaging. We investigated clinical outcomes, endocrinopathies, and neuropsychological sequelae associated with tectal plate gliomas. Twenty-six patients with tectal plate glioma were identified in a 20-year retrospective review. Clinical outcomes, treatments, endocrine function, neuropsychological testing outcomes and radiographic imaging were reviewed for possible signs correlating with tumor progression. Among 26 patients, 19 presented with signs or symptoms of increased intracranial pressure (73 %) versus an incidental finding in 7 (27 %). Median follow-up was 46 months (range 8-143 months). Six of 26 (23 %) experienced progressive disease after diagnosis. Five of 26 (19 %) required more than one surgical procedure due to failure of initial endoscopic third ventriculostomy. Seven of 26 had history of endocrine dysfunction, of which, five presented with endocrine dysfunction (precocious puberty or short stature), 1 developed menstrual irregularities after surgical intervention and 1 had preexisting pan hypopituitarism. Of 12 patients with available neuropsychological testing, eleven had at least one indicator of executive functioning in the low-average to impaired range. While tectal plate gliomas have been considered indolent tumors that are rarely progressive, 23 % of patients in our cohort experienced disease progression and required further therapy. Neurocognitive deficits may occur, while endocrine deficiency is uncommon. Regular multidisciplinary oncology follow-up, routine monitoring with MRI and formal neurocognitive evaluation are imperative to provide early recognition of disease progression or recurrent hydrocephalus and to improve school functioning in this population.

Predictors of outcome in palliative colonic stent placement for malignant obstruction

BACKGROUND

Emergency surgery for large bowel obstruction carries significant morbidity and mortality. After initially promising results, concerns have been raised over complication rates for self-expandable metal stents (SEMS) in both the palliative and bridge-to-surgery settings. This article documents the technique used at the authors' institution, and reports on success and complication rates, as well as identifying predictors of endoscopic reintervention or surgical treatment.

METHODS

Data were collected for a prospective cohort of consecutive patients undergoing attempted colonoscopic SEMS insertion at a single institution between 1998 and 2013. Multivariable logistic models were fitted to assess possible predictors of endoscopic reintervention and surgical treatment.

RESULTS

Palliative SEMS insertion was attempted in 146 patients. Primary colorectal cancer was the most common cause of obstruction (95.2 per cent). The majority of patients (77.4 per cent) were treated in an acute setting, with a high technical success rate of 97.3 per cent. The perforation rate was 4.8 per cent and the 30-day procedural mortality rate 2.7 per cent. No predictors of early complications were identified, although patients with metastases and those who received chemotherapy were more likely to have late complications. Some 30.8 per cent of patients required at least one further intervention, with 11.0 per cent of the cohort requiring a stoma. Endoscopic reintervention was largely successful.

CONCLUSION

SEMS offer a valid alternative to operative intervention in the palliative management of malignant large bowel obstruction. Patients receiving chemotherapy are more likely to receive endoscopic reintervention, which is largely successful.

Health and social care services for older male adults in prison: the identification of current service provision and piloting of an assessment and care planning model

Background

Older prisoners are the fastest growing subgroup in the English and Welsh prison estate. Existing research highlights that older prisoners have high health and social care needs and that, currently, these needs routinely remain unmet.

Objectives

(1) To explore the needs of men entering and leaving prison; (2) to describe current provision of services, including integration between health and social care services; and (3) to develop and pilot an intervention for identifying health and social care needs on reception into prison, ensuring that these are systematically addressed during custody.

Methods

The research programme was a mixed-methods study comprising four parts: (1) a study of all prisons in England and Wales housing older adult men, establishing current availability and degree of integration between health and social care services through a national survey and qualitative interviews; (2) establishing the health and social care needs of older men entering prison, including experiences of reception into custody, through structured (n = 100) and semistructured (n = 27) interviews; (3) the development and implementation of an intervention to identify and manage the health, social care and custodial needs of older men entering prison; and (4) exploration of the health and social care needs of older men released from prison into the community through qualitative interviews with older prisoners prior to and following discharge from prison. Descriptive statistics were produced for all quantitative data, and qualitative data were analysed using the constant comparison method.

Results

The number of older prisoner leads has increased in recent years but they do not all appear always to be active in their roles, nor in receipt of specialist training. Nearly half (44%) of establishments do not have an older prisoner policy. There is a lack of integration between health and social care services because of ambiguity regarding responsibility for older prisoners' social care. The responsible social service may be located a considerable distance from where the prisoner is held; in such instances, local social services do not co-ordinate their care. The most frequent unmet need on prison entry was the provision of information about care and treatment. Release planning for older prisoners was frequently non-existent.

Limitations

The study used a cut-off age of 60 years as the lower limit for the definition of an older prisoner; evidence has emerged that supports a redefinition of that cut-off to 50 years. Our study examined the care provided for men and this should be considered if contemplating using the Older prisoner Health and Social Care Assessment and Plan (OHSCAP) with older women in prison.

Conclusion

The OHSCAP, developed as part of this study, provided a feasible and acceptable means of identifying and systematically addressing older prisoners' health and social care needs. Future work will include the conduct of a randomised controlled trial to examine the impact of the OHSCAP in terms of improving a range of outcomes, including economic impact.

Funding

The National Institute for Health Research Health Services and Delivery Research programme.

The impact of hospitalisation on discrimination experiences

Background

The aim of the study was to assess the experiences of discrimination as reported by people with mental health problems and to explore the impact of hospitalisation.

Methods

306 people with mental health problems provided sociodemographic data and data on discrimination using the discrimination and stigma scale version 12 (DISC-12) with the domains negative experienced discrimination, anticipated discrimination, overcoming stigma and discrimination, and positive experienced discrimination. Logistic regression analysis was used to test the impact of hospitalisation on discrimination, controlled for age, gender, education, employment, diagnosis and having been prescribed medication.

Results

Hospitalisation had a major impact on negative discrimination: People were more likely to be treated unfairly in making or keeping friends, in marriage or divorce, by people in their neighbourhood, in social life, by mental health staff and in terms of privacy, if they had been hospitalised. They were also more likely to be avoided or shunned by people who knew about the mental health problem. People with a history of hospitalisation also reported more anticipated discrimination: They had stopped themselves more often from having a close personal relationship and concealed their mental health problem from others more often than those without a history of hospitalisation. However, people who had been hospitalised also experienced more positive discrimination in terms of being treated more positively in getting welfare benefits or disability pensions and in housing.

Conclusion

Findings suggest that treatment in hospital contributed to a higher extent to experienced discrimination than treatment in the community.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) plasma concentrations in residents of Paritutu, New Zealand: evidence of historical exposure

An assessment of community exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was undertaken in Paritutu, New Zealand. The suburb lies adjacent to an agrichemical facility that produced 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), between 1962 and 1987. Soil TCDD measurements from 73 nearby addresses demonstrated a pattern of TCDD deposition consistent with an aerial plume following the prevailing local wind patterns and the agrichemical plant as the point source. Blood samples were taken from 52 volunteers having lived for three or more years in Paritutu between 1962 and 1987. Candidate selection focused primarily on individuals who were most likely to show elevated TCDD blood lipid levels when compared to age and gender stratified national average blood concentrations, and secondarily on individuals that provided additional information about specific exposure periods, potential exposures of younger age groups, and specific dietary patterns. A multipathway exposure model was used to estimate serum TCDD levels in each participant. Age and gender-specific TCDD elimination kinetics were also considered. Historical TCDD environmental concentrations were back-calculated from soil concentrations at each residence assuming TCDD releases occurred pre-dominantly between 1962 and 1975. Serum was analysed for chlorinated dibenzodioxins and dibenzofurans, and a subset was analysed for dioxin-like polychlorinated biphenyls. TCDD in serum lipid exceeded two standard deviations above national background levels for 14 participants, and 3 standard deviations for 10 participants. The highest TCDD lipid concentration was 33.3 ng/kg-lipid, or 11 times higher than the comparative 1997 national average. Elevated TCDD concentrations were observed primarily, but not exclusively, in the older study participants who had been in residence in Paritutu before 1968. The study demonstrated TCDD exposure in this community, occurring most likely through the aerial route, and most probably from fugitive emissions during manufacture.

The relationship of glycaemic control and triglycerides in patients with diabetes mellitus: a PreCIS Database Study

AIMS

A common therapeutic approach in patients with type 2 diabetes mellitus who have elevated triglycerides (TGs) is to treat the hyperglycaemia before specifically targeting high TG. The aims of the current study were (i) to determine whether there was a relationship between glycated haemoglobin (HgbA1c) and TG levels at the baseline visit and (ii) to analyse the relationship between DeltaHgbA1c and DeltaTG after treatment.

METHODS

Among 650 consecutive diabetic patients seen in the Cleveland Clinic Preventive Cardiology Department, 372 had both baseline and post-treatment HgbA1c and TG values. We analysed the relationship between baseline HgbA1c and TG as well as between the change in HgbA1c and the change in TG. For analysis, patients were divided into nine groups by tertiles of HgbA1c (< or =6.6, 6.7-7.8 and >7.8%) and TG (< or =1.75, 1.76-3.89 and >3.89 mmol/l) at baseline.

RESULTS

At baseline, there was a small correlation between HgbA1c and TG (r(2) = 0.051; p < 0.001). For the entire group, there was a significant correlation between DeltaHgbA1c and DeltaTG from baseline to follow-up (r(2) = 0.077; p < 0.001). Analyses by tertiles showed that DeltaTG were only associated with changes in two groups: HgbA1c tertile 3 (>7.8%) and TG tertiles 2 (r(2) = 0.24; p < 0.0001) and 3 (r(2) = 0.187; p = 0.003). For every 1% change in the top tertile HgbA1c, there was a 9.3% change in TG (tertile 2) and a 9.8% change in TG (tertile 3).

CONCLUSIONS

These observations suggest that for patients with diabetes mellitus and elevated TG, the effect of HgbA1c reduction has limited effects on TG reduction. Patients may benefit from TG-specific therapy initiated earlier rather than waiting to see effects of glycaemic control.

Mechanisms underlying the metabolic actions of galegine that contribute to weight loss in mice

BACKGROUND AND PURPOSE

Galegine and guanidine, originally isolated from Galega officinalis, led to the development of the biguanides. The weight-reducing effects of galegine have not previously been studied and the present investigation was undertaken to determine its mechanism(s) of action.

EXPERIMENTAL APPROACH

Body weight and food intake were examined in mice. Glucose uptake and acetyl-CoA carboxylase activity were studied in 3T3-L1 adipocytes and L6 myotubes and AMP activated protein kinase (AMPK) activity was examined in cell lines. The gene expression of some enzymes involved in fat metabolism was examined in 3T3-L1 adipocytes.

KEY RESULTS

Galegine administered in the diet reduced body weight in mice. Pair-feeding indicated that at least part of this effect was independent of reduced food intake. In 3T3-L1 adipocytes and L6 myotubes, galegine (50 microM-3 mM) stimulated glucose uptake. Galegine (1-300 microM) also reduced isoprenaline-mediated lipolysis in 3T3-L1 adipocytes and inhibited acetyl-CoA carboxylase activity in 3T3-L1 adipocytes and L6 myotubes. Galegine (500 microM) down-regulated genes concerned with fatty acid synthesis, including fatty acid synthase and its upstream regulator SREBP. Galegine (10 microM and above) produced a concentration-dependent activation of AMP activated protein kinase (AMPK) in H4IIE rat hepatoma, HEK293 human kidney cells, 3T3-L1 adipocytes and L6 myotubes.

CONCLUSIONS AND IMPLICATIONS

Activation of AMPK can explain many of the effects of galegine, including enhanced glucose uptake and inhibition of acetyl-CoA carboxylase. Inhibition of acetyl-CoA carboxylase both inhibits fatty acid synthesis and stimulates fatty acid oxidation, and this may to contribute to the in vivo effect of galegine on body weight.