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Biology subjects

Hendricks, L.

Publications and source records attributed to Hendricks, L..

2 recordsLinked to original sources

Osteocalcin of maternal and embryonic origins synergize to establish homeostasis in offspring

Many physiological functions regulated by osteocalcin are affected in adult offspring of mothers experiencing an unhealthy pregnancy. Furthermore, osteocalcin signaling during gestation influences cognition and adrenal steroidogenesis in adult mice. Together these observations suggest that osteocalcin functions during pregnancy may be a broader determinant of organismal homeostasis in adult mammals than previously thought. To test this hypothesis, we analyzed in unchallenged wildtype and Osteocalcin-deficient, newborn, and adult mice of various genotypes and origin, and that were maintained on different genetic backgrounds, the functions of osteocalcin in the pancreas, liver and testes and their molecular underpinnings. This analysis revealed that providing mothers are themselves Osteocalcin-deficient, Osteocalcin haploinsufficiency in embryos hampers insulin secretion, liver gluconeogenesis, glucose homeostasis, testes steroidogenesis in adult offspring; inhibits cell proliferation in developing pancreatic islets and testes; and disrupts distinct programs of gene expression in these organs and in the brain. This study indicates that through their synergistic regulation of multiple physiological functions, osteocalcin ofmaternal and embryonic origins contributes to the establishment and maintenance of organismal homeostasis in newborn and adult offspring.

physiology↗

Both Lipopolysaccharide And Lipoteichoic Acids Potently Induce Anomalous Fibrin Amyloid Formation: Assessment With Novel Amytracker™ Stains

In recent work, we discovered that the presence of highly substoichiometric amounts (10-8 molar ratio) of lipopolysaccharide (LPS) from Gram-negative bacteria caused fibrinogen clotting to lead to the formation of an amyloid form of fibrin. We here show that the broadly equivalent lipoteichoic acids (LTAs) from two species of Gram-positive bacteria have similarly (if not more) potent effects. Using thioflavin T fluorescence to detect amyloid as before, the addition of low concentrations of free ferric ion is found to have similar effects. Luminescent conjugated oligothiophene dyes (LCOs), marketed under the trade name AmytrackerTM, also stain classical amyloid structures. We here show that they too give very large fluorescence enhancements when clotting is initiated in the presence of the four amyloidogens (LPS, ferric ions and two LTA types). The staining patterns differ significantly as a function of both the amyloidogens and the dyes used to assess them, indicating clearly that the nature of the clots formed is different. This is also the case when clotting is measured viscometrically using thromboelastography. Overall, the data provide further evidence for an important role of bacterial cell wall products in the various coagulopathies that are observable in chronic, inflammatory diseases. The assays may have potential in both diagnostics and therapeutics.

biophysics↗