α-Ketoglutarate-Dependent KDM6 Histone Demethylases and Interferon-Stimulated Gene Expression in Lupus

OBJECTIVE

We aimed to investigate the hypothesis that interferon (IFN)-stimulated gene (ISG) expression in systemic lupus erythematosus (SLE) monocytes is linked to changes in metabolic reprogramming and epigenetic regulation of ISG expression.

METHODS

Monocytes from healthy volunteers and patients with SLE at baseline or following IFNα treatment were analyzed by extracellular flux analysis, proteomics, metabolomics, chromatin immunoprecipitation, and gene expression. The histone demethylases KDM6A/B were inhibited using glycogen synthase kinase J4 (GSK-J4). GSK-J4 was tested in pristane and resiquimod (R848) models of IFN-driven SLE.

RESULTS

SLE monocytes had enhanced rates of glycolysis and oxidative phosphorylation compared to healthy control monocytes, as well as increased levels of isocitrate dehydrogenase and its product, α-ketoglutarate (α-KG). Because α-KG is a required cofactor for histone demethylases KDM6A and KDM6B, we hypothesized that IFNα may be driving "trained immune" responses through altering histone methylation. IFNα priming (day 1) resulted in a sustained increase in the expression of ISGs in primed cells (day 5) and enhanced expression on restimulation with IFNα. Importantly, decreased H3K27 trimethylation was observed at the promoters of ISGs following IFNα priming. Finally, GSK-J4 (KDM6A/B inhibitor) resulted in decreased ISG expression in SLE patient monocytes, as well as reduced autoantibody production, ISG expression, and kidney pathology in R848-treated BALB/c mice.

CONCLUSION

Our study suggests long-term IFNα exposure alters the epigenetic regulation of ISG expression in SLE monocytes via changes in immunometabolism, a mechanism reflecting trained immunity to type I IFN. Importantly, it opens the possibility that targeting histone-modifying enzymes, such as KDM6A/B, may reduce IFN responses in SLE.

A multi-stem cell basis for craniosynostosis and calvarial mineralization

Craniosynostosis is a group of disorders of premature calvarial suture fusion. The identity of the calvarial stem cells (CSCs) that produce fusion-driving osteoblasts in craniosynostosis remains poorly understood. Here we show that both physiologic calvarial mineralization and pathologic calvarial fusion in craniosynostosis reflect the interaction of two separate stem cell lineages; a previously identified cathepsin K (CTSK) lineage CSC1 (CTSK+ CSC) and a separate discoidin domain-containing receptor 2 (DDR2) lineage stem cell (DDR2+ CSC) that we identified in this study. Deletion of Twist1, a gene associated with craniosynostosis in humans2,3, solely in CTSK+ CSCs is sufficient to drive craniosynostosis in mice, but the sites that are destined to fuse exhibit an unexpected depletion of CTSK+ CSCs and a corresponding expansion of DDR2+ CSCs, with DDR2+ CSC expansion being a direct maladaptive response to CTSK+ CSC depletion. DDR2+ CSCs display full stemness features, and our results establish the presence of two distinct stem cell lineages in the sutures, with both populations contributing to physiologic calvarial mineralization. DDR2+ CSCs mediate a distinct form of endochondral ossification without the typical haematopoietic marrow formation. Implantation of DDR2+ CSCs into suture sites is sufficient to induce fusion, and this phenotype was prevented by co-transplantation of CTSK+ CSCs. Finally, the human counterparts of DDR2+ CSCs and CTSK+ CSCs display conserved functional properties in xenograft assays. The interaction between these two stem cell populations provides a new biologic interface for the modulation of calvarial mineralization and suture patency.

A vertebral skeletal stem cell lineage driving metastasis

Vertebral bone is subject to a distinct set of disease processes from long bones, including a much higher rate of solid tumour metastases1-4. The basis for this distinct biology of vertebral bone has so far remained unknown. Here we identify a vertebral skeletal stem cell (vSSC) that co-expresses ZIC1 and PAX1 together with additional cell surface markers. vSSCs display formal evidence of stemness, including self-renewal, label retention and sitting at the apex of their differentiation hierarchy. vSSCs are physiologic mediators of vertebral bone formation, as genetic blockade of the ability of vSSCs to generate osteoblasts results in defects in the vertebral neural arch and body. Human counterparts of vSSCs can be identified in vertebral endplate specimens and display a conserved differentiation hierarchy and stemness features. Multiple lines of evidence indicate that vSSCs contribute to the high rates of vertebral metastatic tropism observed in breast cancer, owing in part to increased secretion of the novel metastatic trophic factor MFGE8. Together, our results indicate that vSSCs are distinct from other skeletal stem cells and mediate the unique physiology and pathology of vertebrae, including contributing to the high rate of vertebral metastasis.

Identification of a stem cell mediating osteoblast versus adipocyte lineage selection

Most skeletal fragility disorders are characterized by bone loss with a concurrent gain in marrow adipocytes 1-8. This suggests that a cell that forms adipocytes at the expense of osteoblasts is central to the pathogenesis of skeletal disorders. However, this cellular point of bifurcation between adipocyte and osteoblast differentiation pathways remains unknown. Here, we identify a new cell type defined by co-expression of skeletal stem cell and adipocyte precursor markers, 9-13 (CD24+CD29+ skeletal stem cells (SSCs)), that serves as a key cellular point of bifurcation between the osteoblast and adipocyte differentiation pathways, giving rise to closely related osteoblast and adipocyte lineage-restricted precursors. CD24+CD29+SSCs comprise a small fraction of SSCs, and only this fraction displays full stemness features, including the ability to undergo serial transplantation. In line with serving as the osteoblast/adipocyte bipotent cell, the "bone to fat" tissue remodeling occurring in models of postmenopausal osteoporosis or after high fat diet exposure occur in part by reprogramming these CD24+CD29+SSCs to change their output of lineage-restricted precursors. Lastly, as subcutaneous white adipose tissue displays a similar set of CD24+CD29+ stem cells and related lineage-restricted progenitors, these findings provide a new schema explaining the stem cell basis of bone versus adipose tissue production that unifies multiple mesenchymal tissues.

Discovery of a Vertebral Skeletal Stem Cell Driving Spinal Metastases

Vertebral bone is subject to a distinct set of disease processes from those of long bones, notably including a much higher rate of solid tumor metastases that cannot be explained by passive blood flow distribution alone. The basis for this distinct biology of vertebral bone has remained elusive. Here we identify a vertebral skeletal stem cell (vSSC), co-expressing the transcription factors ZIC1 and PAX1 together with additional cell surface markers, whose expression profile and function are markedly distinct from those of long bone skeletal stem cells (lbSSCs). vSSCs display formal evidence of stemness, including self-renewal, label retention and sitting at the apex of their differentiation hierarchy. Lineage tracing of vSSCs confirms that they make a persistent contribution to multiple mature cell lineages in the native vertebrae. vSSCs are physiologic mediators of spine mineralization, as genetic blockade of the ability of vSSCs to generate osteoblasts results in defects in the vertebral neural arch and body. Human counterparts of vSSCs can be identified in vertebral endplate specimens and display a conserved differentiation hierarchy and stemness. Multiple lines of evidence indicate that vSSCs contribute to the high rates of vertebral metastatic tropism observed clinically in breast cancer. Specifically, when an organoid system is used to place both vSSCs and lbSSCs in an identical anatomic context, vSSC-lineage cells are more efficient than lbSSC-lineage cells at recruiting metastases, a phenotype that is due in part to increased secretion of the novel metastatic trophic factor MFGE8. Similarly, genetically targeting loss-of-function to the vSSC lineage results in reduced metastasis rates in the native vertebral environment. Taken together, vSSCs are distinct from other skeletal stem cells and mediate the unique physiology and pathology of vertebrae, including contributing to the high rate of metastatic seeding of the vertebrae.

Osteoclasts are not a source of SLIT3

The axon guidance cue SLIT3 was identified as an osteoanabolic agent in two recent reports. However, these reports conflict in their nomination of osteoblasts versus osteoclasts as the key producers of skeletal SLIT3 and additionally offer conflicting data on the effects of SLIT3 on osteoclastogenesis. Here, aiming to address this discrepancy, we found no observable SLIT3 expression during human or mouse osteoclastogenesis and the only modest SLIT3-mediated effects on osteoclast differentiation. Conditional deletion of SLIT3 in cathepsin K (CTSK)-positive cells, including osteoclasts, had no effect on the number of osteoclast progenitors, in vitro osteoclast differentiation, overall bone mass, or bone resorption/formation parameters. Similar results were observed with the deletion of SLIT3 in LysM-positive cells, including osteoclast lineage cells. Consistent with this finding, bone marrow chimeras made from Slit3 -/- donors that lacked SLIT3 expression at all stages of osteoclast development displayed normal bone mass relative to controls. Taken in context, multiple lines of evidence were unable to identify the physiologic function of osteoclast-derived SLIT3, indicating that osteoblasts are the major source of skeletal SLIT3.

B-05 Age of Seizure Onset Predicted Categorical Fluency Switching and Anxiety in People with Temporal Lobe Epilepsy

Objective

To examine whether demographic variables can assist in predicting executive dysfunction in individuals with temporal lobe epilepsy (TLE).

Method

Data were collected from presurgical evaluations of 13 individuals with TLE (67% females, mean age 34 ± 12) at the University of California, San Francisco Epilepsy Center. Executive functions were assessed using subtests from the D-KEFS (Verbal Fluency and Color/Word Interference Tests) and the Trail Making Test B. Given that depression and anxiety symptoms have been previously shown to be associated with poorer executive performance in individuals with TLE (Paradiso et al., 2001), predictability of the BDI-II and BAI scores were also tested. Linear regression analyses were used to test predictive values of demographic variables (age, age at seizure onset [ASO], years of education, gender, and right vs. left temporal epileptogenic source).

Results

ASO (β = .75, p = .021), gender (β = .632, p = .041), and education (β = .555, p = .05) explained 66% of the variance in the Verbal Fluency Switching scaled scores (R²=.66, F(4,8)= 3.876, p = .049). Education (β = .772, p = .009) and ASO (β = .686, p = .023) explained 70% of the variance in Verbal Fluency Switching Accuracy scaled scores (R² = .708, F(4,8) = 4.844, p = .028). Age (β = -.862, p = .003) and seizure onset (β = .457, p = .049) explained 52% of the variance in BAI scores (R² = .525, F(4,16) = 3.319, p = .032).

Conclusions

ASO predicted category switching and anxiety severity, while none of the demographic variables explored in this study predicted visuomotor switching. Further research should explore the efficacy of early interventions to protect against future executive dysfunction in TLE.

The Unmixing Problem: A Guide to Applying Single-Cell RNA Sequencing to Bone

Bone is composed of a complex mixture of many dynamic cell types. Flow cytometry and in vivo lineage tracing have offered early progress toward deconvoluting this heterogeneous mixture of cells into functionally well-defined populations suitable for further studies. Single-cell sequencing is poised as a key complementary technique to better understand the cellular basis of bone metabolism and development. However, single-cell sequencing approaches still have important limitations, including transcriptional effects of cell isolation and sparse sampling of the transcriptome, that must be considered during experimental design and analysis to harness the power of this approach. Accounting for these limitations requires a deep knowledge of the tissue under study. Therefore, with the emergence of accessible tools for conducting and analyzing single-cell RNA sequencing (scRNA-seq) experiments, bone biologists will be ideal leaders in the application of scRNA-seq to the skeleton. Here we provide an overview of the steps involved with a single-cell sequencing analysis of bone, focusing on practical considerations needed for a successful study. © 2019 American Society for Bone and Mineral Research.

Endometriosis and adverse maternal, fetal and neonatal outcomes, a systematic review and meta-analysis

STUDY QUESTION

How is endometriosis associated with adverse maternal, fetal and neonatal outcomes of pregnancy?

SUMMARY ANSWER

Women with endometriosis are at elevated risk for serious and important adverse maternal (pre-eclampsia, gestational diabetes, placenta praevia and Cesarean section) and fetal or neonatal outcomes (preterm birth, PPROM, small for gestational age, stillbirth and neonatal death).

WHAT IS KNOWN ALREADY

A number of studies have shown an association between endometriosis and certain adverse maternal and fetal outcomes, but the results have been conflicting with potential for confounding by the use of assisted reproductive technology.

STUDY DESIGN, SIZE, DURATION

A systematic review and meta-analysis of observational studies (1 January 1990-31 December 2017) that evaluated the effect of endometriosis on maternal, fetal and neonatal outcomes was conducted.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Studies were considered for inclusion if they were prospective or retrospective cohort or case-control studies; included women greater than 20 weeks gestational age with endometriosis; included a control group of gravid women without endometriosis; and, reported at least one of the outcomes of interest. Each study was reviewed for inclusion, data were extracted and risk of bias was assessed by two independent reviewers.

MAIN RESULTS AND THE ROLE OF CHANCE

The search strategy identified 33 studies (sample size, n = 3 280 488) for inclusion. Compared with women without endometriosis, women with endometriosis had higher odds of pre-eclampsia (odds ratio [OR] = 1.18 [1.01-1.39]), gestational hypertension and/or pre-eclampsia (OR = 1.21 [1.05-1.39]), gestational diabetes (OR = 1.26 [1.03-1.55]), gestational cholestasis (OR = 4.87 [1.85-12.83]), placenta praevia (OR = 3.31 [2.37, 4.63]), antepartum hemorrhage (OR = 1.69 [1.38-2.07]), antepartum hospital admissions (OR = 3.18 [2.60-3.87]), malpresentation (OR = 1.71 [1.34, 2.18]), labor dystocia (OR = 1.45 [1.04-2.01]) and cesarean section (OR = 1.86 [1.51-2.29]). Fetuses and neonates of women with endometriosis were also more likely to have preterm premature rupture of membranes (OR = 2.33 [1.39-3.90]), preterm birth (OR = 1.70 [1.40-2.06]), small for gestational age <10th% (OR = 1.28 [1.11-1.49]), NICU admission (OR = 1.39 [1.08-1.78]), stillbirth (OR = 1.29 [1.10, 1.52]) and neonatal death (MOR = 1.78 [1.46-2.16]). Among the subgroup of women who conceived spontaneously, endometriosis was found to be associated with placenta praevia, cesarean section, preterm birth and low birth weight. Among the subgroup of women who conceived with the use of assisted reproductive technology, endometriosis was found to be associated with placenta praevia and preterm birth.

LIMITATIONS, REASONS FOR CAUTION

As with any systematic review, the review is limited by the quality of the included studies. The diagnosis for endometriosis and the selection of comparison groups were not uniform across studies. However, the effect of potential misclassification would be bias towards the null hypothesis.

WIDER IMPLICATIONS OF THE FINDINGS

The association between endometriosis with the important and serious pregnancy outcomes observed in our meta-analysis, in particular stillbirth and neonatal death, is concerning and warrants further studies to elucidate the mechanisms for the observed findings.

STUDY FUNDING/COMPETING INTEREST(S)

Dr Shifana Lalani is supported by a Physicians' Services Incorporated Foundation Research Grant, and Dr Innie Chen is supported by a University of Ottawa Clinical Research Chair in Reproductive Population Health and Health Services. Dr Singh declares conflicts of interests with Bayer, Abvie, Allergan and Cooper Surgical. All other authors have no conflicts of interests to declare.

REGISTRATION NUMBER

PROSPERO CRD42015013911.

Discovery of a periosteal stem cell mediating intramembranous bone formation

Bone consists of separate inner endosteal and outer periosteal compartments, each with distinct contributions to bone physiology and each maintaining separate pools of cells owing to physical separation by the bone cortex. The skeletal stem cell that gives rise to endosteal osteoblasts has been extensively studied; however, the identity of periosteal stem cells remains unclear^1-5. Here we identify a periosteal stem cell (PSC) that is present in the long bones and calvarium of mice, displays clonal multipotency and self-renewal, and sits at the apex of a differentiation hierarchy. Single-cell and bulk transcriptional profiling show that PSCs display transcriptional signatures that are distinct from those of other skeletal stem cells and mature mesenchymal cells. Whereas other skeletal stem cells form bone via an initial cartilage template using the endochondral pathway⁴, PSCs form bone via a direct intramembranous route, providing a cellular basis for the divergence between intramembranous versus endochondral developmental pathways. However, there is plasticity in this division, as PSCs acquire endochondral bone formation capacity in response to injury. Genetic blockade of the ability of PSCs to give rise to bone-forming osteoblasts results in selective impairments in cortical bone architecture and defects in fracture healing. A cell analogous to mouse PSCs is present in the human periosteum, raising the possibility that PSCs are attractive targets for drug and cellular therapy for skeletal disorders. The identification of PSCs provides evidence that bone contains multiple pools of stem cells, each with distinct physiologic functions.

Targeting skeletal endothelium to ameliorate bone loss

Recent studies have identified a specialized subset of CD31hiendomucinhi (CD31hiEMCNhi) vascular endothelium that positively regulates bone formation. However, it remains unclear how CD31hiEMCNhi endothelium levels are coupled to anabolic bone formation. Mice with an osteoblast-specific deletion of Shn3, which have markedly elevated bone formation, demonstrated an increase in CD31hiEMCNhi endothelium. Transcriptomic analysis identified SLIT3 as an osteoblast-derived, SHN3-regulated proangiogenic factor. Genetic deletion of Slit3 reduced skeletal CD31hiEMCNhi endothelium, resulted in low bone mass because of impaired bone formation and partially reversed the high bone mass phenotype of Shn3-/- mice. This coupling between osteoblasts and CD31hiEMCNhi endothelium is essential for bone healing, as shown by defective fracture repair in SLIT3-mutant mice and enhanced fracture repair in SHN3-mutant mice. Finally, administration of recombinant SLIT3 both enhanced bone fracture healing and counteracted bone loss in a mouse model of postmenopausal osteoporosis. Thus, drugs that target the SLIT3 pathway may represent a new approach for vascular-targeted osteoanabolic therapy to treat bone loss.

A mighty khatun

A graceful lady limped [...]

A mighty khatun

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c-Jun N-Terminal Kinases (JNKs) Are Critical Mediators of Osteoblast Activity In Vivo

The c-Jun N-terminal kinases (JNKs) are ancient and evolutionarily conserved regulators of proliferation, differentiation, and cell death responses. Currently, in vitro studies offer conflicting data about whether the JNK pathway augments or represses osteoblast differentiation, and the contribution of the JNK pathway to regulation of bone mass in vivo remains unclear. Here we show that Jnk1^-/- mice display severe osteopenia due to impaired bone formation, whereas Jnk2^-/- mice display a mild osteopenia only evident in long bones. In order to both confirm that these effects were osteoblast intrinsic and assess whether redundancy with JNK1 masks a potential contribution of JNK2, mice with a conditional deletion of both JNK1 and JNK2 floxed conditional alleles in osteoblasts (Jnk1-2^osx ) were bred. These mice displayed a similar degree of osteopenia to Jnk1^-/- mice due to decreased bone formation. In vitro, Jnk1^-/- osteoblasts display a selective defect in the late stages of osteoblast differentiation with impaired mineralization activity. Downstream of JNK1, phosphorylation of JUN is impaired in Jnk1^-/- osteoblasts. Transcriptome analysis showed that JNK1 is required for upregulation of several osteoblast-derived proangiogenic factors such as IGF2 and VEGFa. Accordingly, JNK1 deletion results in a significant reduction skeletal vasculature in mice. Taken together, this study establishes that JNK1 is a key mediator of osteoblast function in vivo and in vitro. © 2017 American Society for Bone and Mineral Research.

THYROID DYSFUNCTION AND INFERTILITY TREATMENT

Objective

To find out the relationship of thyroid hormone profile of females with outcomes after intra cytoplasmic sperm injection (ICSI).

Method

It was a cross sectional study conducted in Islamabad Clinic Serving Infertile Couple from June 2013 till August 2015. T3 (triiodo thyronine), T4 (thyroxine) and TSH (thyroid stimulating hormone) of 168 consented females was estimated after they underwent the first step of treatment protocol (ovarian down regulation) for ICSI. Pregnant group had ß hCG result more than 25 IU/mL while the rest were included in the non-pregnant group. Both groups were compared by using independent sample t-test. Pearson correlation coefficient was used to associate T3 and T4 with other pregnancy variables with their significance.

Results

Non pregnant women had significantly higher mean values for T3 and T4 as compared to pregnant women (p <0.05, p<0.01). Difference in mean TSH value between non-pregnant and pregnant women was not significant p=0.08. It was found that T4 gave significant negative association with grading of embryo-I, blastocysts formed, thickness of endometrium and number of gestational sacs.

Conclusion

Disturbance in thyroid profile with raised T4 levels leads to alteration in endometrial thickness and quality of embryos required for implantation and hence conception.

Endotoxemia-related attenuation of interleukin-1 secretion in thermally injured patients

The present study examines the effect of post-burn endotoxemia on the capacity for the in vitro induction of interleukin-1 (IL-1)β synthesis by either inflammatory or non-inflammatory stimuli. Adherent cell (AC) cultures from patients with severe burns (n = 14, 25-65% total body surface area) were stimulated with LPS, phorbol ester (TPA) or IL-2 and studied simultaneously with intact or LPS-pretreated preparations from normal donors (n = 9). Levels of spontaneously released IL-1β in unstimulated AC cultures from patients and in LPS-pretreated preparations from normal individuals were highly elevated. However, LPS- and IL-2-related IL-1β production in such cultures was significantly decreased (P < 0.01-0.05). In contrast, in the majority of patients' cultures and LPS-pretreated normal AC preparations, TPA-induced IL-1β production remained relatively unaffected. In all patients studied, reduced capacity for the LPS-induced IL-1 production was observed concurrently with a significant (P < 0.05) elevation in plasma endotoxin content. Diminished secretion of IL-1β coincided also with a profound reduction of IL-2-dependent IFNγ production in patient cultures and in LPS-pretreated normal cultures. Thus, in the burn patient, endotoxemia-related specific desensitization may develop and, combined with other intrinsic mechanisms, restrict the pathophysiological sequelae of continuous bacterial stimulation.

OS032. Pharmacotherapy for pre-eclampsia in low and middle income countries: An analysis of essential medicines lists (EMLS)

INTRODUCTION

Pre-eclampsia is the second leading cause of maternal mortality in low and middle income countries (LMIC). Pharmacological management of pre-eclampsia has five major components including antihypertensive therapy for severe and non-severe hypertension, magnesium sulphate for prevention or treatment of eclampsia, treatment of pre-eclampsia-related end-organ complications, antenatal corticosteroids for acceleration of fetal pulmonary maturity given iatrogenic preterm delivery for maternal and/or fetal indications, and labour induction for such indicated deliveries. Essential medicines are defined by the World Health Organization (WHO) as "drugs that satisfy the health care needs of the majority of the population". Essential Medicines Lists (EMLs) detail these essential medicines within an individual country and support the argument that the medication should be routinely available.

OBJECTIVES

To determine how many drugs required for comprehensive pre-eclampsia management are listed in national EMLs of LMIC.

METHODS

We conducted a descriptive analysis of relevant drug prevalence on identified EMLs. We searched for the national EMLs of the 144 LMIC identified by the World Bank. EMLs were collected by broad based internet searches and in collaboration with the WHO. The EMLs were surveyed for therapies for the different aspects of pre-eclampsia management: hypertension (non-severe and severe with oral or parenteral agents), eclampsia, pre-eclampsia complications (e.g., pulmonary oedema, thrombosis), preterm birth, and labour induction.

RESULTS

EMLs were located and reviewed for 58(40.3%) of LMIC. One or more parenteral antihypertensive agents were listed in 51(87.9%) EMLs. The most common agents were: hydralazine (67.2%), verapamil (58.6%), propranolol (39.7%) and sodium nitroprusside (37.9%); parenteral labetalol was listed by only 19.0% of EMLs. The most prevalent oral antihypertensive therapies listed were: nifedipine (96.6%, usually 10 or 20mg intermediate-acting tablets), methyldopa (94.8%), propranolol (89.7%), and atenolol (87.9%). Captopril, enalapril, hydrochlorothiazide and spironolactone were commonly listed. Magnesium sulphate for prevention and management of eclampsia was present in 86.2% of EMLs (and its antidote, calcium gluconate in 82.8%). To manage complications of pre-eclampsia, oral frusemide was listed in 94.8% of EMLs and parenteral heparin in 91.4%. Most EMLs listed parenteral dexamethasone (91.4%) for acceleration of fetal pulmonary maturity and oxytocin (98.3%) or a prostanoid (usually misoprostol, 39.7%) for labour induction.

CONCLUSION

EMLs of LMIC provide comprehensive coverage of all aspects of recommended pre-eclampsia pharmacotherapy. These EMLs may be used as advocacy tools to ensure the availability of these therapies within each country.

Molecular docking studies of banana flower flavonoids as insulin receptor tyrosine kinase activators as a cure for diabetes mellitus

Diabetes mellitus is a metabolic disorder caused due to insulin deficiency. Banana flower is a rich source of flavonoids that exhibit anti diabetic activity. Insulin receptor is a tetramer that belongs to a family of receptor tyrosine kinases. It contains two alpha subunits that form the extracellular domain and two beta subunits that constitute the intracellular tyrosine kinase domain. Insulin binds to the extracellular region of the receptor and causes conformational changes that lead to the activation of the tyrosine kinase. This leads to autophosphorylation, a step that is crucial in insulin signaling pathway. Hence, compounds that augment insulin receptor tyrosine kinase activity would be useful in the treatment of diabetes mellitus. The 3D structure of IR tyrosine kinase was obtained from PDB database. The list of flavonoids found in banana flower was obtained from USDA database. The structures of the flavonoids were obtained from NCBI Pubchem. Docking analysis of the flavonoids was performed using Autodock 4.0 and Autodock Vina. The results indicate that few of the flavonoids may be potential activators of IR tyrosine kinase.

22q13.3 deletion syndrome: clinical and molecular analysis using array CGH

The 22q13.3 deletion syndrome results from loss of terminal segments of varying sizes at 22qter. Few genotype-phenotype correlations have been found but all patients have mental retardation and severe delay, or absence of, expressive speech. We carried out clinical and molecular characterization of 13 patients. Developmental delay and speech abnormalities were common to all and comparable in frequency and severity to previously reported cases. Array-based comparative genomic hybridization showed the deletions to vary from 95 kb to 8.5 Mb. We also carried out high-resolution 244K array comparative genomic hybridization in 10 of 13 patients, that defined the proximal and distal breakpoints of each deletion and helped determine the size, extent, and gene content within the deletion. Two patients had a smaller 95 kb terminal deletion with breakpoints within the SHANK3 gene while three other patients had a similar 5.5 Mb deletion implying the recurrent nature of these deletions. The two largest deletions were found in patients with ring chromosome 22. No correlation could be made with deletion size and phenotype although complete/partial SHANK3 was deleted in all patients. There are very few reports on array comparative genomic hybridization analysis on patients with the 22q13.3 deletion syndrome, and we aim to accurately characterize these patients both clinically and at the molecular level, to pave the way for further genotype-phenotype correlations. (c) 2010 Wiley-Liss, Inc.

The relationship between changes in self-reported disability (measured by the Health Assessment Questionnaire - HAQ) in scleroderma and improvement of disease status in clinical practice

OBJECTIVES

To determine if a low Health Assessment Questionnaire Disability Index (HAQ-DI) score predicts subsequent improvement over the next one to two years in clinical practice and if a low HAQ is predictive of improvement in early, late, diffuse and limited SSc subsets.

METHODS

HAQs collected at one site annually were used to determine serial relationships in low baseline HAQ and improvement in overall status over the following one to two years. Data were divided into early (< or =3 years) and late, and then further into limited and diffuse SSc subgroups. We verified our results in the Canadian Scleroderma Research Group (CSRG) database.

RESULTS

120 SSc patients had a baseline HAQ-DI of 0.97+/-0.07 (SEM). Low HAQs predicted improvement in overall HAQ at one and two years, but was not statistically significant in predicting physician improvement rating. However, improving HAQs were associated with improvement in physician assessment (better vs. same vs. worse) for overall SSc (p=0.005), early diffuse SSc (p=0.008), overall limited SSc (p=0.02) and late limited SSc (p=0.03) at 1 year (but not at 2 years). The relationship was similar for severity of disease where changes in damage were related to changes in HAQ only over the first year for all 4 subgroups.

CONCLUSION

The HAQ is a useful 'marker' of change in status in clinical practice, where an improved HAQ is associated with improved physician global assessment. The relationship is only helpful for an interval of one year. Low HAQ did not predict subsequent improvement by physician rating in SSc patients.

Effects of vagal denervation on cardiorespiratory and behavioral responses in the newborn lamb

Recently, Wong et al. (Wong KA, Bano A, Rigaux A, Wang B, Bharadwaj B, Schurch S, Green F, Remmers JE, and Hasan SU, J Appl Physiol 85: 849-859, 1998) demonstrated that fetal lambs that have undergone vagal denervation prenatally do not establish adequate alveolar ventilation shortly after birth. In their study, however, vagal denervation was performed prenatally and the deleterious effects of vagal denervation on breathing patterns and gas exchange could have resulted from the prenatal actions of the neurotomy. To quantify the relative roles of pre- vs. postnatal vagal denervation on control of breathing, we studied 14 newborn lambs; 6 were sham operated, and 8 were vagally denervated below the origin of the recurrent laryngeal nerve. Postoperatively, all denervated animals became hypoxemic and seven of eight succumbed to respiratory failure. In vagally denervated lambs, expiratory time increased, whereas respiratory rate, minute ventilation, and lung compliance decreased compared with the sham-operated animals. In the early postoperative period, the frequency of augmented breaths was lower but gradually increased over time in the denervated vs. sham-operated group. The dynamic functional residual capacity was significantly higher than the passive functional residual capacity among the sham-operated group compared with the denervated group. No significant differences were observed in the prevalence of various sleep states and in the amount of total phospholipids or large- and small-aggregate surfactants between the two groups. We provide new evidence indicating that intrauterine actions of denervation are not required to explain the effects of vagal denervation on postnatal survival. Our data suggest that vagal input is critical in the maintenance of normal breathing patterns, end-expiratory lung volume, and gas exchange during the early neonatal period.

Functional impairment in COPD patients: the impact of anxiety and depression

The authors examined the relationship between functional status and comorbid anxiety and depression and the relationship between utilization of health care resources and psychopathology in elderly patients with chronic obstructive pulmonary disease (COPD). Elderly male veterans (N = 43) with COPD completed anxiety, depression, and functional status measures. The authors constructed regression models to explore the contribution of COPD severity, medical burden, depression, and anxiety to the dependent variables of functional impairment and health care utilization. Anxiety and depression contributed significantly to the overall variance in functional status of COPD patients, over and above medical burden and COPD severity, as measured by the 8 scales of the Medical Outcomes Study (MOS) 36-item Short Form Health Survey. Surprisingly, medical burden and COPD severity did not contribute significantly to overall variance in functional status. Few patients were receiving any treatment for anxiety or depression.

Significance of vagal innervation in perinatal breathing and gas exchange

The mechanisms responsible for the establishment of continuous breathing at birth remain unknown. Several studies have shown that postnatal vagal denervation produces deleterious effects on ventilation as well as breathing patterns during the newborn period. However, the validity of these studies was compromised by anesthesia, tracheostomy or possible secondary laryngeal obstruction. We have recently developed an unanesthetized lamb model in which vagal denervation was performed antenatally and below the recurrent laryngeal nerves thereby avoiding anesthesia, tracheostomy and laryngeal paralysis. The denervated animals developed life-threatening respiratory failure shortly after birth, implying that vagal innervation of the lungs plays an essential role in establishing adequate gas exchange in the first hours after birth. We have subsequently investigated various mechanisms of respiratory failure in denervated animals. Our results show that the surfactant system dysfunction and loss of vagally mediated volume feedback likely contributed to the respiratory failure observed in the intrathoracically denervated animal model.

Human pharmacokinetics of intravenous, sublingual, and buccal buprenorphine

Buprenorphine is a potent opioid analgesic used in the treatment of moderate to severe pain. At higher doses, it has demonstrated potential for treating heroin dependence. This study was undertaken to investigate buprenorphine pharmacokinetics by different routes of administration at dosages approximating those used in opioid-dependence studies. Six healthy men who were nondependent but who had a history of heroin use were administered buprenorphine in a crossover design study by intravenous (1.2 mg), sublingual (4.0 mg), and buccal (4.0 mg) routes of administration. Plasma samples were collected up to 96 h and assayed for buprenorphine and norbuprenorphine by negative chemical ionization tandem mass spectrometry. Plasma concentrations of buprenorphine and norbuprenorphine were analyzed by nonlinear regression analysis with standard noncompartmental methods. Buprenorphine biovailability by the sublingual and buccal routes was estimated as 51.4% and 27.8%, respectively, although there was considerable interindividual variability by both routes of administration. The terminal elimination half-lives were longer for the sublingual and buccal routes than for the intravenous route. The extended elimination half-lives may be due to a shallow depot effect involving sequestration of buprenorphine in the oral mucosa. Norbuprenorphine mean peak plasma concentrations were less than 1 ng/mL and were highly variable among different routes of administration and individuals. The terminal elimination half-life of norbuprenorphine was longer than buprenorphine.

Immune deficiency following thermal trauma is associated with apoptotic cell death

Thermal injury-associated specific immune deficiency occurs despite indicators of systemic activation of the lymphoid compartment. We investigated the possibility that postburn immune failure and T cell activation are casually related through activation-induced (apoptotic) cell death. The relationship between the cellular immune response and cell mortality was examined in cultures of peripheral blood mononuclear cells (PBMC) from 14 immunosuppressed patients with extensive burns (35-90% total body surface area). Impaired cellular immunity coincided with significantly reduced cell viability as ascertained by propidium iodide staining and dye reduction assays. Following stimulation with the mitogenic lectin, phytohemagglutinin (PHA), the majority of DNA in patient cultures was fragmented, suggesting the occurrence of apoptotic cell death. Even without stimulation a portion of patient cells was apoptotic as indicated by oligonucleosomal bands on agarose gel electrophoresis. Exogenous interleukin-2 or phorbol ester markedly reduced constitutive as well as PHA-induced DNA fragmentation. In situ demonstration of DNA strand breaks in freshly isolated patient PBMC, by a TdT-based labeling technique, confirmed that a larger fraction (up to 60%) of circulating lymphocytes was undergoing apoptosis on the periphery. These novel observations suggest that apoptosis may play a major role in thermal injury-related cellular immunodeficiency.

Tumor necrosis factor alpha regulation of immunoglobulin secretion in trauma patients

Major trauma-related immune dysfunction is observed at the time of augmented release of immunopathologic mediators. In the present study, T cell-dependent immunoglobulin (Ig) synthesis in peripheral blood mononuclear cell (PBMC) cultures from blunt trauma patients (N = 12, injury severity score (ISS) 27-50), was reduced by 30- > 90%. This coincided with significantly (P < 0.001-0.01) elevated secretion of the biologically active tumor necrosis factor alpha (TNF alpha). Modulation of the TNF alpha activity by anti-TNF alpha antibody (anti-TNF alpha Ab) led to dose-dependent alterations in IgG synthesis. IgG production increased (up to 300%) in cultures treated with 0.5-2 micrograms/ml of the antibody, where low levels of TNF alpha activity often persisted. However, immunoglobulin synthesis was eradicated in preparations exposed to higher concentrations (10 micrograms/ml) of anti-TNF alpha Ab and devoid of TNF alpha biological activity. The treatment with anti-TNF alpha Ab had no effect on mitogen- or alloantigen-induced PBMC proliferation. Thus, in severely traumatized patients, biological activities of endogenous TNF alpha may include modulation of T cell-dependent B lymphocyte function. Immunoregulatory potential of TNF alpha should, therefore, be considered in therapeutic strategies to abrogate its activity.

Modulation of biological responses of normal human mononuclear cells by antiestrogens

The effect of three non-steroidal antiestrogens, Tamoxifen, Toremifene and ICI 164, 384, on various aspects of the immune response was studied in cultures of normal peripheral mononuclear blood cells. The drugs differ somewhat in their effect on the functions tested (pokeweed mitogen-induced immunoglobulin synthesis and cell proliferation, mixed lymphocyte reaction, Interleukin 2 (IL 2) synthesis, IL 2 receptor expression and Tumor Necrosis Factor (TNF alpha) synthesis). However, all three are immunosuppressive. On the other hand, ICI 164, 384 and Tamoxifen were stimulatory for TNF alpha production by adherent cells which may prove as an additional feature in antiestrogen treatment.

IL-2 regulation of soluble IL-2 receptor levels following thermal injury

In the immunosuppressed burn patient serum levels of both IL-2 and a soluble form of IL-2 receptor alpha (sIL-2R alpha) are significantly elevated. Strikingly, the production of these markers by the in vitro activated patients' cells is decreased. This study examines the role of IL-2 in the decreased production of the sIL-2R alpha in vitro in patients with major burns (n = 18, 30 to greater than 70% total body surface area). Peripheral blood mononuclear cell (PBMC) cultures from patients with highly elevated serum sIL-2R alpha, and from healthy controls (n = 12) were activated with concanavalin A (Con A) at initiation. In patients' cultures mitogen-induced increments of sIL-2R alpha levels were significantly lower. There was a significant negative correlation (r = 0.64, P less than 0.001) between a high serum sIL-2R alpha level and a decreased lectin-induced sIL-2R alpha release in vitro. Low levels of sIL-2R alpha in patients' samples were not normalized by increasing the number of T lymphocytes. Also exogenous rIL-1 was without effect, whereas rIL-3 increased sIL-2R alpha release in some cultures. However, sIL-2R alpha levels were significantly increased in patients' cultures by (i) addition of exogenous IL-2; (ii) removal of adherent cells; (iii) addition of cyclooxygenase inhibitor, indomethacin; (iv) bypassing cell surface activation by the combination of the calcium ionophore A23187 and the phorbol ester 12-o-tetradecanoyl acetate. The cyclic AMP-elevating drug, forskolin, abrogated the ability of exogenous IL-2 to increase sIL-2R alpha production. Thus, in the burn patient, the reduced in vitro sIL-2R alpha release appears to relate to abnormalities in IL-2 production and action mediated through its functional surface receptor. Elevated levels of sIL-2R alpha in vivo may, therefore, reflect systemic activation of T lymphocytes in response to biologically active IL-2.

Diffuse and localized glaucomatous field loss in light-sense, flicker and resolution perimetry

A total of 75 eyes in 75 patients with different types of glaucoma (21 eyes with low-tension glaucoma, 49 with primary open-angle glaucoma and 5 with pigmentary glaucoma) were examined by automated light-sense, flicker and resolution perimetry. All fields were classified in a masked fashion as being "normal" (N) or as having "diffuse loss" (D), "localized loss" (L) or "diffuse plus localized loss" (DL). The frequency distributions for the various field loss categories were plotted against the highest intraocular pressure ever reported in the patients' records. The frequency distribution for the purely localized defects showed a peak at 20 mmHg and were markedly skewed to low pressure values, whereas those for both diffuse plus localized damage and purely diffuse loss peaked at about 30 mmHg. The data suggest that diffuse field loss may be an indicator of pressure-induced damage.

Expression and secretion of IL-2 receptor in trauma patients

The high-affinity cell-surface receptor for interleukin-2 (IL-2R) consists of the 75-kilodalton (kd) chain and a 55-kd glycoprotein known as Tac. This report examines the cellular expression of IL-2R and secretion of the soluble form of Tac in immunosuppressed blunt trauma (n = 20, injury severity score -20) and thermally injured (n = 20, Total body surface area greater than 35%) patients. The percentage of IL-2R-expressing peripheral blood mononuclear cells (PBMC) in mitogen-stimulated cultures from patients and age-matched normal donors was determined by direct immunofluorescence with a monoclonal anti-Tac followed by flow cytometry analysis. Levels of soluble Tac in patient sera were measured by a monoclonal antibody-based enzyme-linked immunosorbent assay. Expression of Tac antigen by mitogen-activated PBMC cultures from blunt trauma patients was transiently reduced (by as much as 40%) in 4 of 14 patients examined. Levels of serum Tac were significantly elevated (p less than 0.05) in 15 of 20 blunt trauma patients ranging from 750 to 3000 U/mL compared with 180 to 420 U/mL in control subjects. All burn patients studied 10 to 50 days after the injury demonstrated a significant reduction (by 50% to more than 90%) in the percentage of IL-2 receptor-bearing cells. Similarly serum levels of IL-2R increased significantly (p less than 0.001 to 0.05) in all burn patients studied, reaching concentrations as high as 5500 U/mL. These results suggest that major trauma, whether mechanical or thermal, induces alterations in the T-lymphocyte activation process. However the degree and duration of such changes may vary based on the nature of the injury.