The circadecadal rhythm of oscillation of umbilical cord blood parameters correlates with geomagnetic activity – An analysis of long-term measurements (1999–2011)

Recently, we have shown that the contents of total nucleated cells (TNCs) and CD34⁺ hematopoietic stem and progenitor cells (CD34⁺ HSPCs) as well as the cord blood volume (CBV) in umbilical cord blood (UCB) show a circadecadal (~10 years) rhythm of oscillation. This observation was based on an analysis of 17,936 cord blood donations collected during 1999–2011. The aim of the present study was to investigate whether this circadecadal rhythm of oscillation in TNCs, CD34⁺ HSPCs and CBV is related to geomagnetic activity. For the analysis, the yearly averages of TNCs, CD34⁺ HSPCs and CBV in UCB were correlated with geomagnetic activity (Dcx index). Our analysis revealed that (i) all three UCB parameters were statistically significantly correlated with the level of geomagnetic activity, (ii) CBV showed a linear correlation with the Dcx index (r = 0.5290), (iii) the number of TNCs and CD34⁺ HSPCs were quadratic inversely correlated with the Dcx index (r = ?0.5343 and r = ?0.7749, respectively). Furthermore, (iv) CBV and the number of TNCs were not statistically significantly correlated with the number of either modest or intense geomagnetic storms per year, but (v) the number of CD34⁺ HSPCs was statistically significantly correlated with the number of modest (r = 0.9253) as well as intense (r = 0.8683) geomagnetic storms per year. In conclusion, our study suggests that UCB parameters correlate with the state of the geomagnetic field (GMF) modulated by solar activity. Possible biophysical mechanisms underlying this observation, as well as the outcome of these findings, are discussed.     

Evaluations of bioantioxidants in cryopreservation of umbilical cord blood using natural cryoprotectants and low concentrations of dimethylsulfoxide

Transplantation using hematopoietic stem cells from umbilical cord blood (UCB) is a life-saving treatment option for patients with select oncologic diseases, immunologic diseases, bone marrow failure, and others. Often this transplant modality requires cryopreservation and storage of hematopoietic stem cells (HSC), which need to remain cryopreserved in UCB banks for possible future use. The most widely used cryoprotectant is dimethylsulfoxide (Me₂SO), but at 37 °C, it is toxic to cells and for patients, infusion of cryopreserved HSC with Me₂SO has been associated with side effects. Freezing of cells leads to chemical change of cellular components, which results in physical disruption. Reactive oxygen species (ROS) generation also has been implicated as cause of damage to cells during freezing. We assessed the ability of two bioantioxidants and two disaccharides, to enhance the cryopreservation of UCB. UCB was processed and subjected to cryopreservation in solutions containing different concentrations of Me₂SO, bioantioxidants and disaccharides. Samples were thawed, and then analysed by: flow cytometry analysis, CFU assay and MTT viability assay. In this study, our analyses showed that antioxidants, principally catalase, performed greater preservation of: CD34+ cells, CD123+ cells, colony-forming units and cell viability, all post-thawed, compared with the standard solution of cryopreservation. Our present studies show that the addition of catalase improved the cryopreservation outcome. Catalase may act on reducing levels of ROS, further indicating that accumulation of free radicals indeed leads to death in cryopreserved hematopoietic cells.     

Evaluation of a clinical-grade,cryopreserved, ex vivo-expanded stem cell product from cryopreserved primary umbilical cord blood demonstrates multilineage hematopoietic engraftment in mouse xenografts

Background aimsAllogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative therapy for a wide range of malignant and genetic disorders of the hematopoietic and immune systems. Umbilical cord blood (UCB) is a readily available source of stem cells for allo-HSCT, but the small fixed number of hematopoietic stem and progenitor cells (HSPCs) found in a single unit limits its widespread use in adult recipients. The authors have previously reported that culturing UCB-CD34⁺ cells in serum-free media supplemented with a combination of cytokines and the histone deacetylase inhibitor valproic acid (VPA) led to expansion of the numbers of functional HSPCs. Such fresh expanded product has been advanced to the clinic and is currently evaluated in an ongoing clinical trial in patients with hematological malignancies undergoing allo-HSCT. Here the authors report on the cryopreservation of this cellular product under current Good Manufacturing Practice (cGMP).MethodscGMP VPA-mediated expansion was initiated with CD34⁺ cells isolated from cryopreserved primary UCB collections, and the functionality after a second cryopreservation step of the expanded product evaluted in vitro and in mouse xenografts.ResultsThe authors found that the cryopreserved VPA-expanded grafts were characterized by a high degree of viability, retention of HSPC phenotypic subtypes and maintenance of long-term multilineage repopulation capacity in immunocompromised mice. All cellular and functional parameters tested were comparable between the fresh and cryopreserved VPA-expanded cellular products.ConclusionsThe authors’ results demonstrate and support the practicality of cryopreservation of VPA-expanded stem cell grafts derived from UCB-CD34⁺ cells for clinical utilization.     

Evaluation of trehalose and sucrose as cryoprotectants for hematopoietic stem cells of umbilical cord blood

Bone marrow transplantation (BMT) is a therapeutic procedure that involves transplantation of hematopoietic stem cells (HSC). To date, there are three sources of HSC for clinical use: bone marrow; mobilized peripheral blood; and umbilical cord blood (UCB). Depending on the stem cell source or type of transplantation, these cells are cryopreserved. The most widely used cryoprotectant is dimethylsulfoxide (Me₂SO) 10% (v/v), but infusion of Me₂SO-cryopreserved cells is frequently associated with serious side effects in patients. In this study, we assessed the use of trehalose and sucrose for cryopreservation of UCB cells in combination with reduced amounts of Me₂SO. The post-thawed cells were counted and tested for viability with Trypan blue, the proportion of HSC was determined by flow cytometry, and the proportion of hematopoeitic progenitor cells was measured by a colony-forming unit (CFU) assay. A solution of 30 mmol/L trehalose with 2.5% Me₂SO (v/v) or 60 mmol/L sucrose with 5% Me₂SO (v/v) produced results similar to those for 10% (v/v) Me₂SO in terms of the clonogenic potential of progenitor cells, cell viability, and numbers of CD45⁺/34⁺ cells in post-thawed cord blood cryopreserved for a minimum of 2 weeks. Thus, cord blood, as other HSC, can be cryopreserved with 1/4 the standard Me₂SO concentration with the addition of disaccharides. The use of Me₂SO at low concentrations in the cryopreservation solution may improve the safety of hematopoietic cell transplantation by reducing the side effects on the patient.     

Short‐ and long‐term effects on mAb‐producing CHO cell lines after cryopreservation

Cryopreservation provides the foundation for research, development, and manufacturing operations in the CHO‐based biopharmaceutical industry. Despite its criticality, studies are lacking that explicitly demonstrate that the routine cell banking process and the potential stress and damage during cryopreservation and recovery from thaw have no lasting detrimental effects on CHO cells. Statistics are also scarce on the decline of cell‐specific productivity (Q_p) over time for recombinant CHO cells developed using the glutamine synthetase (GS)‐based methionine sulfoximine (MSX) selection system. To address these gaps, we evaluated the impact of freeze‐thaw on 24 recombinant CHO cell lines (generated by the GS/MSX selection system) using a series of production culture assays. Across the panel of cell lines expressing one of three monoclonal antibodies (mAbs), freeze‐thaw did not result in any significant impact beyond the initial post‐thaw passages. Production cultures sourced from cryopreserved cells and their non‐cryopreserved counterparts yielded similar performance (growth, viability, and productivity), product quality (size, charge, and glycosylation distributions), and flow cytometric profiles (intracellular mAb expression). However, many production cultures yielded lower Q_p at increased cell age: 17 of the 24 cell lines displayed ≥20% Q_p decline after ～2–3 months of passaging, irrespective of whether the cells were previously cryopreserved. The frequency of Q_p decline underscores the continued need for understanding the underlying mechanisms and for careful clone selection. Because our experiments were designed to decouple the effects of cryopreservation from those of cell age, we could conclusively rule out freeze‐thaw as a cause for Q_p decline. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:463–477, 2018     

Gene expression profiles of cryopreserved CD34 human umbilical cord blood cells are related to their bone marrow reconstitution abilities in mouse xenografts

Human umbilical cord blood (UCB) cells are an alternative source of hematopoietic stem cells for treatment of leukemia and other diseases. It is very difficult to assess the quality of UCB cells in the clinical situation. Here, we sought to assess the quality of UCB cells by transplantation to immunodeficient mice. Cryopreserved CD34⁺ UCB cells from twelve different human donors were transplanted into sublethally irradiated NOD/shi-scid Jic mice. In parallel, the gene expression profiles of the UCB cells were determined from oligonucleotide microarrays. UCB cells from three donors failed to establish an engraftment in the host mice, while the other nine succeeded to various extents. Gene expression profiling indicated that 71 genes, including HOXB4, C/EBP-β, and ETS2, were specifically overexpressed and 23 genes were suppressed more than 2-fold in the successful UCB cells compared to those that failed. Functional annotation revealed that cell growth and cell cycle regulators were more abundant in the successful UCB cells. Our results suggest that hematopoietic ability may vary among cryopreserved UCB cells and that this ability can be distinguished by profiling expression of certain sets of genes.     

In Vitro Modification of Sex Expression in Mulberry (Morus Alba) by Ethrel and Silver Nitrate

This paper compared the behavior of a diverse set of wheat genotypes in their tissue culture response. Significant differences were detected in plant regeneration, culture efficiency, and regeneration capacity when mature embryos of 47 wheat cultivars, breeding lines, and the common wheat progenitors, Triticum monococcum, T.tauschii, and Aegilops speltoides were compared. Although not currently used in wheat tissue culture, mature embryo-derived callus of cv. Zak (SWS), Scarlet (HRS), Tara (SWS), Jagger (HRW), UC 1036 (HRS), and Kyle durum showed better or comparable plant regeneration than commonly cultured cultivars Fielder and Bobwhite. Of the three diploid wheat progenitors tested, Ae. speltoides regenerated the most plants. In one replicated experiment, callus induction was correlated with culture efficiency (r = 0.42; p = 0.002) and regeneration capacity (r = 0.39; p = 0.002), and in a second larger screen, callus induction correlated with the total number of plants regenerated (r = 0.6; p = 0.001. Immature and mature embryos of Bobwhite and Crocus were compared for callus induction and plant regeneration. Immature embryos were superior explants in terms of plant regeneration. However, sufficient numbers of plants can be regenerated from mature embryos saving on growth facility resources and time required for the collection of immature embryos.     

Effective expansion of umbilical cord blood hematopoietic stem/progenitor cells by regulation of microencapsulated osteoblasts under hypoxic condition

The expansion of hematopoietic stem/progenitor cells (HSPCs) from umbilical cord blood (UCB) with the support of microencapsulated osteoblasts under hypoxia environment was investigated. The expansion of HSPCs was evaluated through the total number of UCB mononuclear cells (MNCs) produced, their repopulating potential with the colony-forming unit assay (CFU-Cs) and CD34⁺ phenotypic analysis with flow cytometry. At the end of 7 days of culture, the UCB-MNCs, CFU-Cs and CD34⁺ cells had achieved 18.7 ± 1.6, 11.6 ± 0.9 and 23.4 ± 2-fold expansions, respectively, in the test groups. These were significantly different from those in control groups. Microencapsulated osteoblasts under hypoxia conditions had therefore a significant effect on the expansion potential of HSPCs in vitro.     

Inhibition of MEK/ERK signalling pathway promotes erythroid differentiation and reduces HSCs engraftment in ex vivo expanded haematopoietic stem cells

The MEK/ERK pathway is found to be important in regulating different biological processes such as proliferation, differentiation and survival in a wide variety of cells. However, its role in self‐renewal of haematopoietic stem cells is controversial and remains to be clarified. The aim of this study was to understand the role of MEK/ERK pathway in ex vivo expansion of mononuclear cells (MNCs) and purified CD34⁺ cells, both derived from human umbilical cord blood (hUCB). Based on our results, culturing the cells in the presence of an inhibitor of MEK/ERK pathway—PD0325901 (PD)—significantly reduces the expansion of CD34⁺ and CD34⁺ CD38^? cells, while there is no change in the expression of stemness‐related genes (HOXB4, BMI1). Moreover, in vivo analysis demonstrates that PD reduces engraftment capacity of ex vivo expanded CD34⁺ cells. Notably, when ERK pathway is blocked in UCB‐MNCs, spontaneous erythroid differentiation is promoted, found in concomitant with increasing number of burst‐forming unit‐erythroid colony (BFU‐E) as well as enhancement of erythroid glycophorin‐A marker. These results are in total conformity with up‐regulation of some erythroid enhancer genes (TAL1, GATA2, LMO2) and down‐regulation of some erythroid repressor genes (JUN, PU1) as well. Taken together, our results support the idea that MEK/ERK pathway has a critical role in achieving the correct balance between self‐renewal and differentiation of UCB cells. Also, we suggest that inhibition of ERK signalling could likely be a new key for erythroid induction of UCB‐haematopoietic progenitor cells.     

Chromosomal evidence of hemiclonal and all-paternal offspring production in Bacillus rossius-grandii benazzii (Insecta Phasmatodea)

The stick insects Bacillus rossius-grandii benazzii and B. rossius-grandii grandii naturally reproduce by hybridogenesis and androgenesis. The hybrid karyotype of the former (2n=35, XX female; 34, X0 male) clearly sums up a B. rossius haploset (r) with n=18 and a B. grandii benazzii one (gb) with n=17. The two sets keep the parental features for C-heterochromatin amount (much larger in the gb complement) and satellites/NORs (nuclear organizer regions) (more numerous and variably located in the r set); hybridogenetically produced males always show severely impaired gametogenesis and are therefore sterile, whereas hybridogenetic females are fertile. Reproductive, karyological and cytogenetical properties of the hybridogenetic system have been exploited to obtain the chromosomal evidence of whole haploset exchanges. In progenies obtained by crossing B. rossiusgrandii benazzii females to B. rossius males with either standard or repatterned (with Robertsonian fusions) karyotypes, there has always been complete agreement between electrophoretically genotyped and karyologically analyzed hybridogenetic offspring: the unassorted maternal r haploset (r ^m) is transmitted and the gb ^m haploset replaced by that of the fathering male (r ^p), thus evidencing the hemiclonal reproduction and the new r ^m-r ^p chromosomal constitution. New karyotype traits of the offspring relate to chromosome number (2n=36, female; 35, male), C-heterochromatin pattern (the heterochromatin-rich gb haploset completely disappears) and satellite/NOR features (corresponding to r ^m plus r ^p locations). The same crosses also produce genetically and chromosomally all-paternal descendants (androgenetics), of both sexes and fully fertile, with an r ^p r ^p structure. These androgenetic progeny show segregation for alleles and chromosomes at which fathering males are heterozygous: it was therefore possible to demonstrate that androgenetics can derive from syngamy of two sperm nuclei, of the several present in the polyspermic hybridogenetic egg. The production of androgenetics from field fertilized females of B. rossius-grandii benazzii, B. rossius-grandii grandii and parthenogenetic Bacillus whitei (=B. rossius/grandii grandii) suggests the occurrence of unsuspected relationships between hybrids and their parental species, so that the hybrids cannot be simply considered as sexual parasites. Furthermore, there is a suggestion of evolution of parthenogenetic clonal species from selection of initially hybridogenetic strains. The ability to produce uniparental progeny naturally from the spermatic genome may open a new field of investigation on genomic imprinting.     

Neuroprotective cytokines repress PUMA induction in the 1-methyl-4-phenylpyridinium (MPP(+)) model of Parkinson's disease

The hematopoietic cytokines erythropoietin (Epo) and granulocyte-colony stimulating factor (G-CSF) provide neuroprotection in several in vitro and in vivo models of Parkinson’s disease (PD). The molecular mechanism by which Epo and G-CSF signals reduce the neuronal death in PD is not clear. Here, we show that in rat pheochromocytoma PC12 cells, Epo and G-CSF efficiently repressed the 1-methyl-4-phenylpyridinium (MPP⁺)-induced expression of the proapoptotic protein PUMA (p53 up-regulated modulator of apoptosis). Accordingly, Epo and G-CSF treatment reduced the PC12 cell fraction that underwent apoptosis by MPP⁺ treatment and thus improved cell viability. Downregulation of PUMA expression by Epo and G-CSF in MPP⁺-treated PC12 cells seems to be mediated by repression of p53, as the expression of p53 was increased by MPP⁺-treatment and reduced by Epo and G-CSF. Together, these results suggest that the neuroprotective activities of Epo and G-CSF in an experimental model of PD involve the repression of the apoptosis-inducing action of PUMA.     

Cell culture and in vitro studies of fresh and cryopreserved human insulinoma

Summary Dispersed cells from both fresh and cryopreserved human insulinoma have been maintained in cell culture. Initial yield of viable cells was 50% for fresh and 25% for cryopreserved tissue. Viability of cells in culture was documented by increasing numbers of cells (doubling time approximately 5 d initially and 2 d at the sixth subculture for both fresh and cryopreserved tissue) and continued release of insulin over time (approximately 100 ng/ml per 10⁵ cells at 10 d and 175 ng/ml per 10⁵ cells at 30 d of culture for both fresh and cryopreserved tissue). Evidence that cells growing in culture were beta cells was provided by: (a) recovery of intracellular and extracellular immunoreactive insulin (IRI), (b) electron microscopic morphology, and (c) immunohistochemical staining. Cells from fresh insulinoma incubated with increasing concentrations of extracellular glucose released increasing amounts of IRI up to approximately 15 mM glucose, which paralleled changes in plasma insulin obtained during a preoperative glucose tolerance test. Under an Intergovernmental Personnel Act Exchange from the Department of Surgery, University of California, Davis, Sacramento Medical Center.     

Enhanced Erythrocyte Adhesiveness/Aggregation in Obesity Corresponds to Low‐Grade Inflammation

Objective: Previous studies have suggested that obesity enhances the inflammatory response, producing macromolecules involved in the induction and/or maintenance of increased erythrocyte aggregation. The objectives of this study were to evaluate the correlation between inflammation markers, erythrocyte adhesiveness/aggregation, and the degree of obesity and to assess phosphatidylserine expression on erythrocyte surface membrane of obese vs. nonobese individuals. Research Methods and Procedures: Erythrocyte adhesiveness/aggregation in the peripheral venous blood was evaluated by using a new biomarker, phosphatidylserine expression was assessed by means of flow cytometry, and markers of inflammation were measured in 65 subjects: 30 obese [body mass index (BMI) = 41 ± 7.7 kg/m²] and 35 nonobese (BMI = 24 ± 2.7 kg/m²) individuals. Pearson correlations and Student's t test were performed. Results: A highly significant difference was noted in the degree of erythrocyte adhesiveness/aggregation and markers of inflammation between the study groups. BMI correlated with erythrocyte adhesiveness/aggregation (r = 0.42, p = 0.001), erythrocyte sedimentation rate (r = 0.42, p = 0.001), high‐sensitive C‐reactive protein (r = 0.55, p < 10^?4), fibrinogen (r = 0.37, p = 0.004), and white blood cell count (r = 0.45, p < 10^?4). The degree of erythrocyte adhesiveness/aggregation correlated with erythrocyte sedimentation rate (r = 0.5, p < 10^?4), high‐sensitive C‐reactive protein (r = 0.56, p < 10^?4), fibrinogen (r = 0.54, p < 10^?4), and white blood cell count (r = 0.32, p = 0.01). Discussion: Our results suggest that obesity‐related erythrocyte adhesiveness/aggregation is probably mediated through increased concentrations of adhesive macromolecules in the circulation and not necessarily through hyperlipidemia or phosphatidylserine exposure on erythrocyte's membrane.     

Quality evaluation of umbilical cord blood progenitor cells cryopreserved with a small-scale automated liquid nitrogen system

The performance of a small-scale automated cryopreservation and storage system (Mini-BioArchive system) used in the banking of umbilical cord blood (UCB) units was evaluated. After thawing the units, the viability and recovery of cells, as well as the recovery rate of hematopoietic progenitor cells (HPCs) such as CD34⁺ cells, colony-forming unit-granulocyte-macrophage (CFU-GM), and total CFU were analyzed. Twenty UCB units cryopreserved using the automated system and stored for a median of 34 days were analyzed. Mean CD34⁺ cell viabilities before freezing were 99.8 ± 0.5% and after thawing were 99.8 ± 0.4% in the large bag compartments and 99.7 ± 0.5% in the small compartments. The mean recovery values for total nucleated cells, CD34⁺ cells, CFU-GM, and total CFU were 94.8 ± 16.0%, 99.3 ± 18.6%, 103.9 ± 20.6%, and 94.3 ± 12.5%, respectively in the large compartments, and 95.8 ± 25.9%, 106.8 ± 23.9%, 101.3 ± 23.3%, and 93.8 ± 19.2%, respectively in the small compartments. A small-scale automated cryopreservation and storage system did not impair the clonogenic capacity of UCB HPCs. This cryopreservation system could provide cellular products adequate for UCB banking and HPC transplantation.     

General description of Lake Peipsi-Pihkva

Neural networks and multiple linear regression models of the abundance of brown trout (Salmo trutta L.) on the mesohabitat scale were developed from combinations of physical habitat variables in 220 channel morphodynamic units (pools, riffles, runs, etc.) of 11 different streams in the central Pyrenean mountains. For all the 220 morphodynamic units, the determination coefficients obtained between the estimated and observed values of density or biomass were significantly higher for the neural network (r ² adjusted= 0.93 and r ² adjusted=0.92 (p<0.01) for biomass and density respectively with the neural network, against r ² adjusted=0.69 (p<0.01) and r ² adjusted = 0.54 (p<0.01) with multiple linear regression). Validation of the multivariate models and learning of the neural network developed from 165 randomly chosen channel morphodynamic units, was tested on the 55 other channel morphodynamic units. This showed that the biomass and density estimated by both methods were significantly related to the observed biomass and density. Determination coefficients were significantly higher for the neural network (r ² adjusted =0.72 (p<0.01) and 0.81 (p<0.01) for biomass and density respectively) than for the multiple regression model (r ² adjusted=0.59 and r ² adjusted=0.37 for biomass and density respectively). The present study shows the advantages of the backpropagation procedure with neural networks over multiple linear regression analysis, at least in the field of stochastic salmonid ecology.     

Elevated serum monocyte chemoattractant protein-4 and chronic inflammation in overweight subjects

Objective: Chronic inflammation observed in obesity has been reported to be implicated in the development of atherosclerosis. We screened candidate chemokines that link chronic inflammation and obesity. Research Methods and Procedures: Japanese overweight (n = 39, BMI 28.7 ± 0.65 kg/m²) and normal‐weight (n = 24, BMI 22.3 ± 0.45 kg/m²) subjects were enrolled. Using antibody‐based protein microarray, spot intensities of monocyte chemoattractant protein (MCP)‐4, eotaxin, and eotaxin‐2 correlated with anthropometric parameters. We further measured serum concentration of these chemokines and mRNA levels in adipose tissues obtained from volunteers. Results: Serum MCP‐4 levels showed positive correlation with BMI (r = 0.318, p = 0.014), waist (r = 0.316, p = 0.018), and waist‐to‐hip ratio (WHR) (r = 0.264, p = 0.049). Furthermore, MCP‐4 correlated with homeostasis model assessment of insulin resistance (r = 0.392, p = 0.002), high‐sensitivity C‐reactive protein (hsCRP) (r = 0.350, p = 0.006). In step‐wise multiple regression analyses, hsCRP independently correlated with MCP‐4 levels. The expression of MCP‐4 mRNA in visceral adipose tissue positively correlates with BMI. Serum eotaxin levels correlate with BMI (r = 0.262, p = 0.045) and WHR (r = 0.383, p = 0.003). Serum eotaxin‐2 levels correlated with BMI (r = 0.464, p < 0.001), waist (r = 0.333, p = 0.017), and WHR (r = 0.278, p = 0.048). However, eotaxin and eotaxin‐2 levels did not show significant correlation with hsCRP. Discussion: Serum levels of MCP‐4, eotaxin, and eotaxin‐2, which belong to CC chemokine family and share CC chemokine receptor 3, correlated with BMI. These chemokines, especially MCP‐4, may be critical molecules that link obesity and chronic inflammation.     

Obese reproductive-age women exhibit a proatherogenic inflammatory response during hyperglycemia

Objective: The objective was to determine if physiological hyperglycemia induces a proatherogenic inflammatory response in mononuclear cells (MNCs) in obese reproductive‐age women. Research Methods and Procedures: Seven obese and 6 age‐matched lean women (20 to 39 years of age) underwent a 2‐hour 75‐g oral glucose tolerance test. The release of interleukin‐6 (IL‐6) and interleukin‐1β (IL‐1β) from MNCs cultured in the presence of lipopolysaccharide (LPS) was measured after isolation from blood samples drawn fasting and 2 hours after glucose ingestion. Reactive oxygen species (ROS) generation and intra‐nuclear nuclear factor κB (NFκB) from MNCs were quantified from the same blood samples. Insulin resistance was estimated by homeostasis model assessment of insulin resistance (HOMA‐IR). Total body fat and truncal fat were determined by DXA. Results: Obese women had a higher (p < 0.03) total body fat (42.2 ± 1.1 vs. 27.7 ± 2.0%), truncal fat (42.1 ± 1.2 vs. 22.3 ± 2.4%), and HOMA‐IR (3.3 ± 0.5 vs. 1.8 ± 0.2). LPS‐stimulated IL‐6 release from MNCs was suppressed during hyperglycemia in lean subjects (1884 ± 495 vs. 638 ± 435 pg/mL, p < 0.05) but not in obese women (1184 ± 387 vs. 1403 ± 498 pg/mL). There was a difference (p < 0.05) between groups in the hyperglycemia‐induced MNC‐mediated release of IL‐6 (?1196 ± 475 vs. 219 ± 175 pg/mL) and IL‐1β (?79 ± 43 vs. 17 ± 12 pg/mL). In addition, the obese group exhibited increased (p < 0.05) MNC‐derived ROS generation (39.3 ± 9.9 vs. ?1.0 ± 12.8%) and intra‐nuclear NFκB (9.4 ± 7.3 vs. ?23.5 ± 13.5%). Truncal fat was positively correlated with the MNC‐derived IL‐6 response (ρ = 0.58, p < 0.05) and intra‐nuclear NFκB (ρ = 0.64, p < 0.05). Discussion: These data suggest that obese reproductive‐age women are unable to suppress proatherogenic inflammation during physiological hyperglycemia. Increased adiposity may be a significant contributor to this pro‐inflammatory susceptibility.     

Visceral Adipose Tissue and Markers of the Insulin Resistance Syndrome in Obese Black and White Teenagers

Objective: To determine the relationships between visceral and general adiposity, cardiovascular fitness, and markers of the insulin resistance syndrome in obese black and white teenagers. Research Methods and Procedures: Cross‐sectional survey of 81 obese 13‐ to 16‐year‐old youths. Visceral adipose tissue was measured with magnetic resonance imaging, and percentage body fat was measured with dual‐energy X‐ray absorptiometry. Cardiovascular fitness was assessed with a submaximal treadmill test. Fasting blood samples were analyzed for lipids/lipoproteins and insulin. Resting blood pressure was obtained using an automated cuff. Results: Visceral adipose tissue was significantly correlated with unfavorable levels of: triacylglycerol (r = 0.27, p < 0.05), total cholesterol (r = 0.27, p < 0.05), high‐density lipoprotein cholesterol (r = ?0.26, p < 0.05), the ratio of total cholesterol/high‐density lipoprotein cholesterol (r = 0.42, p < 0.01), low‐density lipoprotein cholesterol (r = 0.27, p < 0.05), apolipoprotein B (r = 0.38, p < 0.01), and systolic blood pressure (r = 0.30, p < 0.01). Multiple regression analyses revealed that visceral adipose tissue was more powerful than percentage body fat for explaining variance in lipoproteins (e.g., for the ratio of total cholesterol/high‐density lipoprotein cholesterol, r² = 0.13, p < 0.01, and for systolic blood pressure, r² = 0.07, p < 0.05). Ethnicity was the most powerful of the demographic predictors for blood lipids (r² = 0.15 for triacylglycerol with lower levels in blacks; r² = 0.10 for high‐density lipoprotein cholesterol with higher levels in blacks; r² = 0.06 for the ratio of total cholesterol/high‐density lipoprotein cholesterol with lower levels in blacks). Cardiovascular fitness was not retained as a significant predictor of markers of the insulin resistance syndrome. Discussion: Some of the deleterious relationships between visceral adiposity and markers for the insulin resistance syndrome seen in adults were already present in these obese young people.     

Pleiotropic Effects of Genes for Insulin Resistance on Adiposity in Baboons

Objective: Previous research has suggested a genetic contribution to the development of insulin resistance and obesity. We hypothesized that the same genes influencing insulin resistance might also contribute to the variation in adiposity. Research Methods and Procedures: A total of 601 (200 male, 401 female) adult baboons (Papio hamadryas) from nine families with pedigrees ranging in size from 43 to 121 were used in this study. Plasma insulin, glucose, C‐peptide, and adiponectin were analyzed, and homeostasis model assessment of insulin resistance (HOMA IR) was calculated. Fat biopsies were collected from omental fat tissue, and triglyceride concentration per gram of fat tissue was determined. Body weight and length were measured, and BMI was derived. Univariate and bivariate quantitative genetic analyses were performed using SOLAR. Results: Insulin, glucose, C‐peptide, and adiponectin levels, HOMA IR, triglyceride concentration of fat tissue, body weight, and BMI were all found to be significantly heritable, with heritabilities ranging from 0.15 to 0.80. Positive genetic correlations (r_Gs) were observed for HOMA IR with C‐peptide (r_G = 0.88 ± 0.10, p = 0.01), triglyceride concentration in fat tissue (r_G = 0.86 ± 0.33, p = 0.02), weight (r_G = 0.50 ± 0.20, p = 0.03), and BMI (r_G = 0.64 ± 0.22, p = 0.02). Discussion: These results suggest that a set of genes contributing to insulin resistance also influence general and central adiposity phenotypes. Further genetic research in a larger sample size is needed to identify the common genes that constitute the genetic basis for the development of insulin resistance and obesity.