Human adipocytes and CD34+ cells from the stromal vascular fraction of the same adipose tissue differ in their energy metabolic enzyme configuration.

Adipose tissue plays a role in energy storage and metabolic balance and is composed of different cell types. The metabolic activity of the tissue itself has been a matter of research for a long time, but comparative data about the energy metabolism of different cell types of human subcutaneous adipose tissue are sparse. Therefore, we compared the activity of major energy metabolic pathways of adipocytes and CD34+ cells from the stromal vascular fraction (SVF) separated from the same tissue. This CD34+ cell fraction is enriched with adipose tissue-derived mesenchymal progenitors, as they account for the largest proportion of CD34+ cells of the SVF. Adipocytes displayed significantly higher mitochondrial enzyme capacities compared to CD34+ SVF-cells, as shown by the higher activities of isocitrate dehydrogenase and ß-hydroxyacyl-CoA dehydrogenase. Inversely, the CD34+ SVF-cells showed higher capacities for cytosolic carbohydrate metabolism, represented by the activity of glycolysis and the pentose phosphate pathway. Thus, the CD34+ SVF-cells may ensure the provision of pentose phosphates and reduction equivalents for the replication of DNA during proliferation. The data indicate that these two cell fractions of the human adipose tissue vary in their metabolic configuration adapted to their physiological demands regarding proliferation and differentiation in vivo.

Masa subcutánea pétrea en el brazo de una mujer joven / Stony-Hard Subcutaneous Mass on the Arm of a Young Woman

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Dietary restriction during development enlarges intestinal and hypodermal lipid droplets in Caenorhabditis elegans.

Dietary restriction (DR) extends lifespan in man species and modulates evolutionary conserved signalling and metabolic pathways. Most of these studies were done in adult animals. Here we investigated fat phenotypes of C. elegans larvae and adults which were exposed to DR during development. This approach was named "developmental-DR" (dDR). Moderate as well as stringent dDR increased the triglyceride to protein ratio in L4 larvae and adult worms. This alteration was accompanied by a marked expansion of intestinal and hypodermal lipid droplets. In comparison to ad libitum condition, the relative proportion of fat stored in large lipid droplets (>50 µm(3)) was increased by a factor of about 5 to 6 in larvae exposed to dDR. Microarray-based expression profiling identified several dDR-regulated genes of lipolysis and lipogenesis which may contribute to the observed fat phenotypes. In conclusion, dDR increases the triglyceride to protein ratio, enlarges lipid droplets and alters the expression of genes functioning in lipid metabolism in C. elegans. These changes might be an effective adaptation to conserve fat stores in animals subjected to limiting food supply during development.

Fatty acid composition in hybrid pigs as based on local fatty Lithuanian breed and wild boar.

The study was designed to investigate the fatty acid composition in longissimus dorsi (LD) and semimembranosus muscles (SM) and subcutaneous tissue of hybrid (1/4 Lithuanian indigenous wattle, 1/4 wild boar and 1/2 Yorkshire or 1/2 Landrace) pigs. The SM showed a tendency to have lower contents of monounsaturated fatty acids (MUFA) and higher contents of polyunsaturated fatty acids (PUFA) than the LD muscle. No statistically significant differences were observed between the muscles in lipid quality indices, i.e., atherogenic (AI) and thrombogenix (TI) indices and the ratio of hypocholesterolemic and hypercholesterolemic fatty acids (h/H). In the SM, the content of PUFA from Yorkshire-sired hybrids was relatively 47.8% higher, including C18:2n-6, C20:4n-6 and DPA (C22:5n-3) that were higher, respectively, by 44.3%, 86.6% and 51.6% in comparison with those from Landrace-sired hybrids. The gilts had a lower content of MUFA, including C18:1 and C20:1n-9 fatty acids in the LD muscle and tended to have a higher content of PUFA in the SM compared to the barrows. Neither the terminal breed in crossing, nor the gender had any significant effects on the proportions of total saturated, MUFA and PUFA in the subcutaneous tissue.

Presurgical evaluation of retroauricular subcutaneous tissue thickness in BAHA surgery.

OBJECTIVE: A growing population of implanted patients benefit from the Bone-Anchored Hearing Aid (BAHA). An important step in the surgery is subcutaneous tissue reduction. The proper preparation of the implant site depends on relevant tissue removal, which is combined with incision, surgical technique, and preliminary retroauricular tissue thickness. STUDY DESIGN: Prospective analysis. SETTING: Authors attempt to measure the retroauricular subcutaneous tissue thickness and try to trace the correlation between retroauricular subcutaneous tissue thickness with objective parameters such as sex, height, weight, and age. PATIENTS: Group of hundred randomly selected patients were enrolled in the study. INTERVENTION(S): Standard ultrasound with liner transducer probe was applied to measure the tissue thickness. MAIN OUTCOME MEASURES: Sex, weight, height, and age were correlated with retroauricular tissue thickness; results also were calculated for body mass index. RESULTS: The retroauricular subcutaneous tissue thickness ranged between 2.0 and 11.0 mm with the mean value of 5.25 mm. Statistical validation revealed strong correlation with weight and body mass index. Statistical difference was found between retroauricular subcutaneous tissue thickness and sex, confirming women to have thinner subcutaneous tissue than men. The age of the patient also was predictive but without the linear correlation. Conducted measurements revealed no association between retroauricular subcutaneous tissue thickness and height of the patients enrolled in the study. CONCLUSION: Our results provide a predictive value during preoperative counseling of patients and planning the surgery. Basic information obtained during the examination can help choose the optimal implantation technique. The ultrasound examination applied in the study turned to be an easy and reliable method to assess the retroauricular tissue thickness before the surgery.

Ce-emerin and LEM-2: essential roles in Caenorhabditis elegans development, muscle function, and mitosis.

Emerin and LEM2 are ubiquitous inner nuclear membrane proteins conserved from humans to Caenorhabditis elegans. Loss of human emerin causes Emery-Dreifuss muscular dystrophy (EDMD). To test the roles of emerin and LEM2 in somatic cells, we used null alleles of both genes to generate C. elegans animals that were either hypomorphic (LEM-2-null and heterozygous for Ce-emerin) or null for both proteins. Single-null and hypomorphic animals were viable and fertile. Double-null animals used the maternal pool of Ce-emerin to develop to the larval L2 stage, then arrested. Nondividing somatic cell nuclei appeared normal, whereas dividing cells had abnormal nuclear envelope and chromatin organization and severe defects in postembryonic cell divisions, including the mesodermal lineage. Life span was unaffected by loss of Ce-emerin alone but was significantly reduced in LEM-2-null animals, and double-null animals had an even shorter life span. In addition to striated muscle defects, double-null animals and LEM-2-null animals showed unexpected defects in smooth muscle activity. These findings implicate human LEM2 mutations as a potential cause of EDMD and further suggest human LEM2 mutations might cause distinct disorders of greater severity, since C. elegans lacking only LEM-2 had significantly reduced life span and smooth muscle activity.

The Caenorhabditis elegans SOMI-1 zinc finger protein and SWI/SNF promote regulation of development by the mir-84 microRNA.

Hundreds of microRNAs (miRNAs) have been discovered in metazoans and plants, and understanding of their biogenesis has advanced dramatically; however, relatively little is known about the cofactors necessary for miRNA regulation of target gene expression. In Caenorhabditis elegans, the conserved miRNA let-7 and its paralogs, including mir-84, control the timing of stage-specific developmental events. To identify factors required for the activity of mir-84 and possibly other miRNAs, we screened for mutations that suppress the developmental defects caused by overexpression of mir-84. Mutations in the somi-1 gene prevent these defects without affecting the expression level of mir-84. Loss of somi-1 also causes phenotypes similar to deletion of mir-84, showing that somi-1 is necessary for the normal function of this miRNA. somi-1 encodes a zinc finger protein that localizes to nuclear foci and binds the promoters of let-60/RAS, lin-14, and lin-28, genes that may be targeted by mir-84 and similar miRNAs. Genetic evidence shows that somi-1 inhibits lin-14 and induction of the vulval precursors by the let-60/RAS pathway. Proteomic and genetic screens identified conserved chromatin-remodeling and homeodomain transcription factor complexes that work with somi-1 to regulate differentiation. Our results suggest that somi-1 coordinates a nuclear response that complements the activity of mir-84.

Stem cells responsible for deer antler regeneration are unable to recapitulate the process of first antler development-revealed through intradermal and subcutaneous tissue transplantation.

Antlers offer a unique model for the study of whether regeneration recapitulates development in a mammalian organ. Research, to date, supports the full recapitulation in antler, but a recent report that subcutaneously transplanted (ST) pedicle periosteum (PP) failed to induce that ectopic antler formation could argue against recapitulation, as antlerogenic periosteum (AP) can readily do so. However, it was not clear in that study whether the result was caused by inability of the PP to interact with the skin or owing to failure to create the required close contact to it. This study was designed to clarify this uncertainty by adopting intradermal transplantation (IT) to achieve the required close contact without the need for significant mass expansion. The results showed that IT of 1/8 of the original AP mass or more was sufficient for antler induction, whereas ST of 1/4-AP or less could not do so within 2 years. The minimum amount of AP required for antler induction using the IT approach was somewhere between 1/8 and 1/12-AP (<30 mg). The results further demonstrated that IT of 62-84 mg PP failed to induce ectopic antler formation, even if the PP had fused with the surrounding skin. Because this mass of PP was 2-3 times the minimum amount of AP required for antler induction, we conclude that PP does not recapitulate AP in induction of ectopic antler development. It is likely that PP has been restricted for antler regeneration and lost the potential to initiate antler development.

Adipocyte- and heart-type fatty acid binding proteins are both expressed in subcutaneous and intramuscular porcine (Sus scrofa) adipocytes.

Adipocyte- (A) and heart- (H) type fatty acid binding proteins (FABP) contribute to efficient fat storage and utilization, respectively. To understand regional-differences in lipid metabolism between tissues, A- and H-FABP transcript and protein levels were studied in adipocytes isolated from subcutaneous adipose tissue or skeletal muscle in growing pigs (Sus scrofa). Interestingly, H-FABP was expressed in adipocytes isolated from both sites. We also showed that A-FABP and H-FABP were expressed at a lower level in intramuscular adipocytes than in subcutaneous adipocytes. A discrepancy was observed between age-related changes in A-FABP content in isolated adipocytes and cell diameter or lipid content variations in tissues during growth.

Glypican LON-2 is a conserved negative regulator of BMP-like signaling in Caenorhabditis elegans.

Bone morphogenetic protein (BMP) pathways are required for a wide variety of developmental and homeostatic decisions, and mutations in signaling components are associated with several diseases. An important aspect of BMP control is the extracellular regulation of these pathways. We show that LON-2 negatively regulates a BMP-like signaling pathway that controls body length in C. elegans. lon-2 acts genetically upstream of the BMP-like gene dbl-1, and loss of lon-2 function results in animals that are longer than normal. LON-2 is a conserved member of the glypican family of heparan sulfate proteoglycans, a family with several members known to regulate growth-factor signaling in many organisms. LON-2 is functionally conserved because the Drosophila glypican gene dally rescues the lon-2(lf) body-size defect. We show that the LON-2 protein binds BMP2 in vitro, and a mutant variation of LON-2 found in lon-2(e2140) animals diminishes this interaction. We propose that LON-2 binding to DBL-1 negatively regulates this pathway in C. elegans by attenuating ligand-receptor interactions. This is the first report of a glypican directly interacting with a growth-factor pathway in C. elegans and provides a mechanistic model for glypican regulation of growth-factor pathways.

Novel heterochronic functions of the Caenorhabditis elegans period-related protein LIN-42.

LIN-42, the Caenorhabditis elegans homolog of the Period (Per) family of circadian rhythm proteins, functions as a member of the heterochronic pathway, regulating temporal cell identities. We demonstrate that lin-42 acts broadly, timing developmental events in the gonad, vulva, and sex myoblasts, in addition to its well-established role in timing terminal differentiation of the hypodermis. In the vulva, sex myoblasts, and hypodermis, lin-42 activity prevents stage-specific cell division patterns from occurring too early. This general function of timing stage-appropriate cell division patterns is shared by the majority of heterochronic genes; their mutation temporally alters stage-specific division patterns. In contrast, lin-42 function in timing gonad morphogenesis is unique among the known heterochronic genes: inactivation of lin-42 causes the elongating gonad arms to reflex too early, a phenotype which implicates lin-42 in temporal regulation of cell migration. Three additional isoforms of lin-42 are identified that expand our view of the lin-42 locus and significantly extend the homology between LIN-42 and other PER family members. We show that, similar to PER proteins, LIN-42 has a dynamic expression pattern; its levels oscillate relative to the molts during postembryonic development. Transformation rescue studies indicate lin-42 is bipartite with respect to function. Intriguingly, the hallmark PAS domain is dispensable for LIN-42 function in transgenic animals.

The combination of SOX5, SOX6, and SOX9 (the SOX trio) provides signals sufficient for induction of permanent cartilage.

OBJECTIVE: To regenerate permanent cartilage, it is crucial to know not only the necessary conditions for chondrogenesis, but also the sufficient conditions. The objective of this study was to determine the signal sufficient for chondrogenesis. METHODS: Embryonic stem cells that had been engineered to fluoresce upon chondrocyte differentiation were treated with combinations of factors necessary for chondrogenesis, and chondrocyte differentiation was detected as fluorescence. We screened for the combination that could induce fluorescence within 3 days. Then, primary mesenchymal stem cells, nonchondrogenic immortalized cell lines, and primary dermal fibroblasts were treated with the combination, and the induction of chondrocyte differentiation was assessed by detecting the expression of the cartilage marker genes and the accumulation of proteoglycan-rich matrix. The effects of monolayer, spheroid, and 3-dimensional culture systems on induction by combinations of transcription factors were compared. The effects of the combination on hypertrophic and osteoblastic differentiation were evaluated by detecting the expression of the characteristic marker genes. RESULTS: No single factor induced fluorescence. Among various combinations examined, only the SOX5, SOX6, and SOX9 combination (the SOX trio) induced fluorescence within 3 days. The SOX trio successfully induced chondrocyte differentiation in all cell types tested, including nonchondrogenic types, and the induction occurred regardless of the culture system used. Contrary to the conventional chondrogenic techniques, the SOX trio suppressed hypertrophic and osteogenic differentiation at the same time. CONCLUSION: These data strongly suggest that the SOX trio provides signals sufficient for the induction of permanent cartilage.

[Detection of malnutrition on admission to hospital]. / Detección de malnutrición al ingreso en el hospital.

In view of the high prevalence of malnutrition in hospitals as shown by some studies and in the light of its direct impact on the increase in morbidity and mortality among hospitalized patients, it is necessary to ensure the early identification of this condition. This would allow appropriate nutritional treatment to be instituted as soon as possible for patients at risk who require it. The present multi-centric study included the participation of hospitals in the northern region of the country which have a Nutrition Unit, with use of the Overall Subjective Assessment and a few basic parameters. The study analyzed the nutritional status on admission of 620 patients hospitalized in the Internal Medicine and General Surgery areas during the months of December, 1999, January, February and March, 2000. We detected moderate malnutrition or suspected malnutrition in 20% of the patients studied and severe malnutrition in 18.2%, with a greater incidence in Internal Medicine. Malnutrition was mainly evidenced by weight loss of more than 5% and a reduction in subcutaneous fat and muscle mass. In addition, there are functional limitations on performing everyday activities. Changes in dietary intake were present in 40.8% of the patients. The associated gastro-intestinal symptoms included anorexia, which affected 37.7% of the group studied. Malnutrition is most frequently linked with infectious diseases, problems in circulation and with the digestive apparatus. We feel that the Overall Subjective Assessment, together with the measurement of height and weight, should be used systematically with patients on admission, as it is a simple and effective method for the identification of patients with nutritional risk.