bluuebunny/crossref_metadata_2025 huggingface dataset:
The Warburg Effect as a VDAC‐Hexokinase‐Mediated Electrical Suppression of Mitochondrial Energy Metabolism
Authors: Lemeshko Victor
Published: June 2021

It is known that nearly half of tumor energy metabolism is provided by glycolysis under normal aerobic conditions (the Warburg Effect) that has been attributed to a respiratory impairment in cancer cells. In the last years, the mitochondrial impairment in cancer cells has been explained by the closure of mitochondrial outer membrane VDACs (porins) by free tubulin (as molecular corks) leading to a suppression of mitochondrial metabolism. Here, we further developed a concept that mitochondria in cancer cells are suppressed by the outer membrane potential (OMP) generated by the metabolically‐dependent mechanism involving the functioning of the VDAC‐hexokinase and/or the ANT(adenine nucleotide translocator)‐VDAC‐hexokinase complexes.These complexes and generated OMP allow initiation of glycolysis preferentially by ATP generated in mitochondria. High selectivity of channeling of mitochondrial energy into the cytosol of cancer cells, to only initiate glycolysis, is achieved due to the electrical closure of free VDACs (non‐bound to hexokinase) by the metabolically‐dependent OMP, by a mode preventing turbo acceleration of glycolysis by cytosolic ATP. Even at low values of OMP, not high enough to completely close VDACs, the ATP flux from the mitochondrial intermembrane space should be almost completely suppressed according to Goldman equation. The value of OMP directly generatedby the VDAC‐hexokinase complex, for example, depends on the Gibbs free energy of the hexokinase reaction. It means that VDAC might function as a physiologically important electrical switcher of tumor energy metabolism, allowing a clear explanation of the Warburg Effect mechanism. (Research grants #111852128625 and #520154531565, Colciencias).
Genotoxic & Cytotoxic Assessment of Hydromethanolic Extract of Senna alata Leaf (HMSa)
Authors: ADEBESIN OLUMIDE , IROANYA ONYEKACHI , ADERONKE SOFOLUWE , OKPUZOR JOY , ODEIGAH PETER
Published: June 2021

The genotoxic & cytotoxic effects of HMSa was assessed using in vivo sperm head abnormality test, Allium cepa test, DNA protection assay & cell cytotoxic effect on K562 cells. Male albino rats were divided into 4 groups. Group 1 received 1ml H2O, groups 2‐4 received 200, 600 & 1000 mg/kg of HMSa daily orally for 63 days respectively. They were weighed & euthanized. The testes & cauda epididymis was evaluated for testicular toxicity & sperm morphology. Onion bulbs were planted in tap H2O for 24 hrs then placed in various conc of HMSa (0.25, 0.50, 0.75, 1 & 2 mg/ml) for 96 hrs. Tap water was used as ‐ve control. The hydroxyl radical induced DNA damage in plasmid pBR322 was used to assess DNA protection while survival of K562 cells exposed to HMSa was measured using the MTT assay. HMSa did not significantly (p 蠅 0.05) increase the weight of the testis & cauda epididymis. The mean % of normal sperm in HMSa groups was not significantly (P 蠅0.05) different. Root lengths significantly decreased in 0.75, 1 & 2 mg/ml conc groups after 48 hrs & 96 hrs compared to control. Mitotic index in the various groups reduced with increased conc of HMSa at the different periods. Chromosomal aberrations such as sticky chromosomes, bridges, fragments & binucleated cells were observed. At 10 & 1000 µg/ml, HMSa exhibited pro‐oxidant activity, but at 100 µg/ml it showed DNA protection activity. Conc dependent toxicity was observed in K562 cells exposed to HMSa from 2.61 to 83.33 µg/ml after 48 hrs, with a CC50 value of 5.59 µg/ml.These results suggests the ability of HMSa to protect DNA & can be attributed to its ability to scavenge hydroxyl radicals. HMSa did not exhibit adverse effect on spermatogenesis but it may be potentially toxic
Tributyltin Decreases Secretion of Interleukin 6 (IL‐6) From Human Immune Cells
Authors: Wilburn Wendy , Brown Shyretha , Whalen Margaret
Published: June 2021

Tributyltin (TBT) is a widespread environmental contaminant due to its use as a biocide (including as an antifungal agent). TBT has been found in human blood samples and has been shown to increase tumors in mammals. IL‐6 is both an anti‐inflammatory and pro‐inflammatory protein that is produced by T lymphocytes (as well as other cells). It regulates cell growth, tissue repair, and immune functions. Previous studies have shown that TBT alters the secretion of cytokines IL‐1β, TNFα, and INFγ from human immune cells. Due to the important role IL‐6 plays in immune responsiveness, it is important to understand whether exposures to TBT are able to disrupt its secretion. Monocyte‐depleted (MD) human peripheral blood mononuclear cells (PBMCs) and natural killer cells (NK) were exposed to TBT at concentrations of 0‐200 nM and monitored for secretion of IL‐6 at 24 h, 48 h, and 6 days using enzyme‐linked immunosorbent assay (ELISA). TBT at concentrations of 10‐200 nM for 24 h, 48 h, or 6 days caused significant decreases in the levels of IL‐6 secreted by MD‐PBMCs and NK cells. IL‐6 has been shown to inhibit IL‐1β and TNFα secretion. Thus, the TBT‐induced decreases of IL‐6 may serve to exacerbate the TBT‐induced increases in IL‐1β and TNFα resulting in unwarranted inflammation. Supported by NIH grants 2T34GM007663‐33 and U54CA163066‐03.
Disruption of Scube2 Impairs Indian Hedgehog‐mediated Osteoblast Differentiation
Authors: Lin Yuh‐Charn , Yan Yu‐Ting , Yang Ruey‐Bing
Published: June 2021

SCUBE2 (signal peptide‐CUB‐EGF domain‐containing protein 2) belongs to a secreted and membrane‐tethered multi‐domain SCUBE protein family composed of 3 members found in vertebrates and mammals. Recent reports suggested that zebrafish scube2 could facilitate sonic hedgehog (SHH) signaling for proper development of slow muscle. However, whether SCUBE2 can regulate the signaling activity of two other HH ligands (IHH and DHH), and the developmental relevance of the SCUBE2‐induced HH signaling in mammals remain poorly understood. In this study, we first showed that as compared with SCUBE1 or 3, SCUBE2 is the most potent modulator of IHH signaling in vitro. In addition, gain and loss‐of‐function studies demonstrated that SCUBE2 exerted an osteogenic function by enhancing IHH‐stimulated osteoblast differentiation in the mouse mesenchymal progenitor cells. Consistent with these in vitro studies and the prominent roles of Ihh in coordinating skeletogenesis, genetic ablation of Scube2 (‐/‐) caused defective endochondral bone formation and impaired IHH‐mediated osteoblast differentiation of ‐/‐ bone‐marrow mesenchymal stromal‐cell cultures. Our data demonstrate that Scube2 plays a key regulatory role in IHH‐stimulated osteoblast differentiation during endochondral bone formation.
Effects of Tributyltin Exposures on Interleukin 1 beta Secretion and Production from Human Immune Cells
Authors: Brown Shyretha , Whalen Margaret
Published: June 2021

Interleukin 1 beta (IL‐1β) is a pro‐inflammatory cytokine that promotes cellular growth and immune response regulation. Produced predominately by both monocytes and macrophages, IL‐1β appears to increase the invasiveness of tumors. Tributyltin (TBT) is an organotin compound that has been used as a biocide in a variety of industrial applications and contaminates the environment. It is found in human blood samples, and mammals with TBT exposure have shown increased incidences of tumors. The current study examines whether exposure to TBT modifies the secretion and production of IL‐1β from lymphocytes. We examined whether exposure to TBT concentrations of 2.5 to 200 nM after 10 min, 30 min, 6h, and 24h alters IL‐1β secretion as well as its intracellular levels in a monocyte‐depleted preparation of human peripheral blood mononuclear cells (MD‐PBMCs). IL‐1β secretion was monitored using enzyme‐linked immunosorbent assay (ELISA) and intracellular levels were analyzed by western blot. Results indicated that 24h exposures to TBT elevated secretion of IL‐1β compared to control cells at all concentrations of TBT and intracellular levels were increased at TBT concentrations of 2.5 to 100nM. After 30 min exposures to TBT there was elevated secretion at the lowest concentrations of TBT (10, 5, and 2.5 nM) while intracellular levels of IL1β increased at TBT concentrations of 5 to 100nM. These data indicate that even very low concentrations of TBT increase the production of IL‐1β in MD‐PBMCs and suggest that increased production accompanies the increase in secretion that is seen with TBT exposures. Supported by NIH grant 5U54CA163066‐02.
Induction of endogenous interleukin 1 alpha limits to one cycle the proliferative response to FGF
Authors: Prudovsky Igor , Poole Ashleigh , Cooper Emily , Kacer Doreen
Published: June 2021

We found that transient FGF stimulation of various cell types results in the novel phenomenon termed “FGF memory” – a sustained blockage of efficient proliferative response to FGF, PDGF or EGF. FGF memory establishment requires HDAC activity, indicating its epigenetic character. FGF treatment stimulates the proinflammatory NFkappaB signaling, which is also critical for FGF memory formation. The search of potential FGF‐induced mediators of FGF memory revealed that FGF induces a sustained expression of the inflammatory cytokine IL1alpha, and this induction is abolished by HDAC inhibitors. Similarly to FGF pretreatment, transient cell treatment with recombinant IL1alphainhibits the proliferative response to further FGF stimulation. However, cells pretreated with FGF or IL1alpha exhibit an enhanced restructuring of actin cytoskeleton and migration in response to FGF. IL1alpha‐prestimulated cells respond to FGF treatment by ERK1/2 phosphorylation and expression of cyclin D1, but not of cyclin A. Both IRAP, a specific inhibitor of IL1 receptor, and neutralizing anti‐IL1alphaantibodies prevent the formation of FGF memory and rescue an efficient proliferative response to FGF restimulation. Thus, FGF memory is mediated by the endogenous IL1alpha. It may play a role in the limitation of proliferative response to tissue damage and prevention of wound‐induced hyperplasia.
A Truncated Fragment of Src Protein Kinase Generated by Calpain‐mediated Cleavage is a Mediator of Neuronal Death in Excitotoxicity.
Authors: Hossain Mohammed
Published: June 2021

Excitotoxicity resulting from overstimulation of glutamate receptors is a major cause of neuronal death in cerebral ischemic stroke. The overstimulated ionotropic glutamate receptors exert their neurotoxic effects in part by overactivation of calpains, which induce neuronal death by catalyzing limited proteolysis of specific cellular proteins. Here, we report that in cultured cortical neurons and in vivo in a rat model of focal ischemic stroke, the tyrosine kinase Src is cleaved by calpains at a site in the N‐terminal unique domain. This generates a truncated Src fragment of ~52 kDa, which we localized predominantly to the cytosol. A cell membrane‐permeable fusion peptide derived from the unique domain of Src prevents calpain from cleaving Src in neurons and protects against excitotoxic neuronal death. To explore the role of the truncated Src fragment in neuronal death, we expressed a recombinant truncated Src fragment in cultured neurons and examined how it affects neuronal survival. Expression of this fragment, which lacks the myristoylation motif and unique domain, was sufficient to induce neuronal death. Furthermore, inactivation of the prosurvival kinase Akt is a key step in its neurotoxic signaling pathway. Because Src maintains neuronal survival, our results implicate calpain cleavage as a molecular switch converting Src from a promoter of cell survival to a mediator of neuronal death in excitotoxicity. Besides unveiling a new pathological action of Src, our discovery of the neurotoxic action of the truncated Src fragment suggests new therapeutic strategies with the potential to minimize brain damage in ischemic stroke
Activated STAT5A interacts with the pyruvate dehydrogenase complex in adipocytes
Authors: Stephens Jacqueline , Richard Allison
Published: June 2021

STAT5 (5A and 5B) mediates signaling by diverse cytokines and growth factors and plays crucial roles in many cellular processes. It is highly expressed in adipocytes, and numerous studies have demonstrated its adipogenic capabilities. Despite recent studies identifying target genes of STAT5 proteins in fat cells, the specificity of action of STAT5 is not well understood. To test the hypothesis that identifying novel STAT5‐interacting proteins would increase our understanding of STAT5 specificity, we affinity purified STAT5A from fat cells under different conditions and used mass spectrometry to discover interacting proteins. One of the proteins identified by this non‐biased approach was PDC‐E2, the E2 subunit of the pyruvate dehydrogenase complex (PDC) that is responsible for the conversion of pyruvate to acetyl‐CoA within the mitochondrial matrix. We validated this interaction in murine and human cultured fat cells and in adipose tissue in vivo. Multiple subunits of PDC interacted with hormone‐activated STAT5A in a dose‐ and time‐dependent manner that coincided with STAT5 tyrosine phosphorylation. Using subcellular fractionation and immunogold electron microscopy, we also observed that STAT5A localized within adipocyte mitochondria. We propose that mitochondrial STAT5A acts as a transcriptional regulator of mitochondrial gene expression. Moreover, it was recently demonstrated that PDC translocates from mitochondria to the nucleus, where it is enzymatically active and capable of generating acetyl‐CoA, which can serve as a substrate for histone acetylation. Currently, we are investigating the role of the nuclear STAT5‐PDC complex in chromatin remodeling and transcriptional regulation within adipocytes.
This work was supported by grant R01DK52968 from NIH to JMS.
TANK Inhibits Genotoxic NF‐κB Activation by Facilitating MCPIP1/USP10‐dependent Deubiquitination of TRAF6
Authors: Wang Wei , Huang Xuan , Niu Jixiao , Fu Mingui , Wu Zhao‐Hui
Published: June 2021

DNA damage‐induced NF‐κB activation plays a critical role in regulating cellular response to genotoxic stress. However, the molecular mechanisms controlling the magnitude and duration of this genotoxic NF‐κB signaling cascade are poorly understood. We recently demonstrated that genotoxic NF‐κB activation is regulated by reversible ubiquitination of essential mediators. Here we show that TRAF family member‐associated NF‐κB activator (TANK) negatively regulates NF‐κB activation by DNA damage via inhibiting ubiquitination of TRAF6. Despite lack of a deubiquitination enzyme domain, TANK was found to negatively regulate ubiquitination of TRAF proteins. We found TANK formed a complex with MCPIP1 and a deubiquitinase USP10, which was essential for USP10‐dependent deubiquitination of TARF6 and resolution of genotoxic NF‐κB activation upon DNA damage. Depletion of TANK in human cells significantly enhanced NF‐κB activation by genotoxic treatments, resulting in enhanced cell survival and increased inflammatory cytokine production upon genotoxic drug treatment. Furthermore, we found that TANK‐MCPIP1‐USP10 complex also decreased TRAF6 ubiquitination in cells treated by IL‐1β or LPS. Accordingly depletion of USP10 enhanced NF‐κB activation by IL‐1β or LPS. Collectively, our data demonstrate that TANK serves as an important negative regulator of NF‐κB signaling cascades induced by genotoxic stress and IL‐1R/TLR stimulation depending on MCPIP1/USP10‐mediated TRAF6 deubiquitination.
The Role of Platelet Derived Growth Factor Induced Phosphorylation of Na+‐H+ Exchanger Isoform 1 in the Regulation of Cell Growth and Movement
Authors: Strong Molly , Mammenga Emily , Provost Joseph , Wallert Mark
Published: June 2021

The hallmarks of cancer are a collection of common, phenotypic changes that define cancer development and progression. One of these hallmarks is sustaining proliferative growth which can occur through changes in growth factor secretion and signaling. The Na+‐ H+ Exchanger Isoform 1 (NHE1) is an 815 amino acid transmembrane protein that regulates cell growth and migration. The platelet derived growth factor receptor is a receptor tyrosine kinase that can activate four distinct protein kinases that phosphorylate NHE1 in five different locations. These kinases and the locations they phosphorylate are: 1) Akt/Protein Kinase B which phosphorylates NHE1 at S648, 2) Rock which phosphorylates NHE1 at T653, 3) Rsk which phosphorylates NHE1 at S703, and 4) Erk which phosphorylates NHE1 at both S770 and S771. To evaluate the role of each of these phosphorylation sites in the regulation of cell proliferation, stress fiber formation, and cell migration we have created a series of cell lines each expressing human NHE1 with one of the phosphorylation sites mutated to an alanine, thus removing that ability for NHE1 to be phosphorylated at that location. We will present the impact of removal of these sites on cell proliferation measured using an XTT assay; stress fiber formation evaluated using AlexaFluor 488 phalloidin; and cell migration measured with a wound healing assay using Ibidi inserts.
Regulation of cAMP‐dependent Protein Kinase A by Src Family Tyrosine Kinases
Authors: Deming Paula , Ballif Bryan , Mann Jacqueline , Weir Marion
Published: June 2021

cAMP‐dependent protein kinase A (PKA) regulates cellular processes including proliferation, survival, differentiation and migration in response to a variety of extracellular cues. Here we report that the catalytic subunit of PKA (PKA‐C) is regulated by Fyn, a member of the Src family of tyrosine kinases (SFKs). PKA‐C was found to be tyrosine‐phosphorylated in cells overexpressing active Fyn. Furthermore, in vitro kinase assays revealed that PKA‐C is indeed a direct substrate of Fyn. Mass spectrometry studies identified tyrosine 69 as the major, if not only, site phosphorylated by Fyn. Mutation of tyrosine 69 to phenylalanine blocked Fyn‐mediated phosphorylation of PKA‐C in cells. Importantly, Fyn‐mediated phosphorylation of PKA‐C altered PKA kinase activity. Kinetic analysis with purified proteins revealed that PKA‐C subunits phosphorylated by Fyn displayed enhanced catalytic efficiency as compared to unphosphorylated control PKA‐C subunits. In cells, overexpression of active Fyn but not kinase‐dead Fyn increased the phosphorylation of endogenous PKA substrates as monitored by western blot using a phospho‐ PKA substrate antibody. Finally, PKA kinase activity was markedly enhanced in cellular extracts prepared from active Fyn‐expressing cells as compared to those prepared from cells overexpressing a kinase‐dead allele of Fyn. Taken together, these results reveal a novel mechanism whereby Fyn can contribute to the regulation of PKA activity through direct phosphorylation of PKA‐C subunits.

This project was supported by a Scientist Development Grant from the American Heart Association to P.B.D.
Delineation of ESDN‐Dependent Signaling Mechanisms Required for Zebrafish Eye Development
Authors: Joy Ryan , Wysolmerski Erin , Ballif Bryan , Ebert Alicia
Published: June 2021

Endothelial and smooth muscle cell‐derived neuropilin‐like protein (ESDN) is an orphan transmembrane receptor, originally found in a screen to identify proteins with signal peptides expressed in vascular endothelial cells. We identified ESDN in two large‐scale phosphoproteomic analyses. The first found ESDN tyrosine phosphorylated from murine embryonic brain. The second was a functional proteomics screen to identify substrates of Src family tyrosine kinases that when phosphorylated would lead to their interaction with the signaling adapter Crk‐Like (CrkL). Given ESDN's extracellular domain is reminiscent of neuropilins, which play important roles in the migration of both vascular endothelial cells and neurons, we examined the expression pattern of Esdn across zebrafish development by in situ hybridization. Esdn expression is strongly neuronal, including in the retina, and greatly overlaps with Crkl expression. Morpholino‐based knockdown of Esdn in zebrafish resulted in incomplete development of the retina and reduced numbers of retinal ganglion cells (RGCs). The morphant phenotype was rescued by injecting RNA encoding full‐length ESDN into zygotes in a dose‐dependent fashion. To assess phenotypes, we scored brain innervation by RGCs in whole‐mount embryos. We also examined RGC cell counts in sectioned embryos during the first three days of development. These data support a role for ESDN in neuronal development, specifically in RGCs.
A Central Role for H2O2 in Insulin Signal Transduction in Cardiac Myocytes
Authors: Sartoretto Juliano , Romero Natalia , Steinhorn Benjamin , Kalwa Hermann , Michel Thomas
Published: June 2021

Molecular mechanisms of insulin action have been extensively characterized in the classic insulin target tissues: fat, liver, and skeletal muscle. But in cardiac myocytes (CM), understanding of insulin‐modulated signaling pathways has lagged far behind. Early studies of insulin action implicated a physiological role for H2O2, but the relationships between insulin and H2O2 in CM signal transduction are almost entirely unexplored. In these studies, we identified a role for H2O2 in insulin signaling pathways in adult mouse CM. Insulin promoted the rapid (maximal at 5 min) robust (10‐ to 18‐fold) and reversible phosphorylation of insulin receptorβTyr1146/1150; IRS‐1 Tyr895; and Akt Ser473/308; these responses all had an EC50 of 1 nM insulin (n=3‐7). Insulin‐dependent phosphorylation of IRS‐1 Ser636/639, mTOR Ser2448, p70S6 Thr389/421, and S6 Ser235/Ser236 showed a slower time course (maximal at 30 min), again with an EC50 of 1 nM insulin and with robust phosphorylation responses (6‐ to 40‐fold increases from baseline; n=3‐7). All of these phosphorylation responses were blocked by the NADPH oxidase inhibitors apocynin and VAS2870, implicating NADPH oxidase‐derived reactive oxygen species in modulating insulin‐dependent phosphorylation responses. Importantly, the cell‐permeant derivatized enzyme PEG‐catalase (which degrades H2O2) attenuated all these insulin‐dependent phosphorylation responses. Our findings implicate NADPH oxidase‐generated H2O2 as a critical determinant of insulin‐dependent signaling responses in CM, and may have important implications for the abnormalities in cardiac function seen in disease states associated with oxidative stress. Research support: NIH and AHA.
C. elegans Troponin I Peptides from Helix 4 and the COOH‐terminus Bind Troponin C in vitro: Novel Implications for the Structural Basis of Troponin's Regulatory Mechanism
Authors: Barnes Dawn , Ono Shoichiro
Published: June 2021

Troponin is a complex of three proteins (troponin I, troponin C, and troponin T) that work in concert to regulate muscle contraction, in a calcium‐dependent manner. Troponin C (TnC) senses changes in intracellular calcium levels. Troponin I (TnI) is sufficient to stabilize tropomyosin in a position to inhibit actomyosin interactions. Biochemical and biophysical studies demonstrated that reversible binding of calcium to TnC induces large conformational changes of TnI. These conformational changes switch on/off actomyosin interactions. TnC and TnI interact at multiple regions in either a calcium‐dependent or calcium‐independent manner; however, the structure and function of several parts, including the N‐terminal and C‐terminal regions of vertebrate cardiac TnI, have not been solved. We utilized Caenorhabditis elegans TnC (PAT‐10) and TnI (UNC‐27) to identify their interactions in vitro. Our objective was to gain insight into TnI and TnC interactions. We synthesized 38 overlapping 20‐residue peptides, covering the entire TnI (UNC‐27) sequence, and tested their interactions with full‐length TnC. TnI (UNC‐27) peptides were spotted on a nitrocellulose membrane and exposed to TnC (PAT‐10). We found TnC‐binding peptides that correspond to four regions of TnI: helix 1, the inhibitory region, helix 4, and the COOH‐terminal tail. Vertebrate TnI helix 1 binds the C‐lobe of TnC. Vertebrate TnI inhibitory region moves toward TnC in the presence of calcium. Helix 4 or the COOH‐terminal tail of vertebrate TnI has not been recognized as a TnC‐binding region. We hypothesize that TnI helix 4 interacts with the N‐lobe of TnC, in a rocking motion, with its C‐terminal region having enhanced binding to TnC when the TnC N‐lobe binds calcium.
Determining the Genotype‐Phenotype Relationship of atg18 Mutants
Authors: Fischer Matthew , Selva Erica
Published: June 2021

8J16 and 9E6 are two independent allelic point mutations in Drosophila melanogaster autophagy‐specific gene 18a (atg18a) located in introns three and four, respectively, of its 5 exon locus at 66B11. The atg188J16 and atg189E6 intronic mutations are not in sequences expected to disrupt transcript processing, yet these mutations cause pupal lethality and neurodegenerative phenotypes by an unknown molecular mechanism. The purpose of this research is to examine the genotype‐phenotype relationship of atg188J16and atg189E6on neuronal maturation using the Drosophila eye as a model. RT‐PCR analysis revealed no detectable effects on atg18 mRNA splicing in either mutant background. In adults, atg188J16 and atg189E6 homozygous mutant eyes are small and display a rough eye phenotype. To understand the basis of this phenotype, homozygous mutant larval imaginal eye discs were examined. ELAV, a pan neuronal marker, showed that photoreceptors differentiate normally, but those that differentiate early are being lost by apoptosis as determined by the increased cleaved caspase 3. These mutations also caused significant death at the morphogenetic furrow, which may result in a smaller pool of photoreceptor progenitors. Hence, autophagy may have roles in both photoreceptor differentiation and maintenance and its absence leads to apoptotic death. Senseless and Prospero expression showed that photoreceptors R8 and R7, respectively, are more refractory to apoptosis as these photoreceptors predominate near the optic stalk. This suggests autophagy is more important for the maintenance of photoreceptors R1, R2, R3 R4, R5 and R6 than R7 and R8.

Acknowledgements given to the Howard Hughes Medical Institute and University of Delaware Undergraduate Research Program for financial support.
Differential Role of Nonmuscle Myosin II Isoforms in Bleb Formation in MCF‐7 Cells
Authors: Dey Sumit , Saha Shekhar , Jana Siddhartha
Published: June 2021

Previous reports suggest that cortical tension plays an important role in bleb formation. Bleb formation has been correlated with Nonmuscle myosin II (NM‐II) activity as inhibition of NM‐II activity leads to decrease in cortical tension and thereby inhibits bleb formation. Whether, three isoforms of NM‐II (NM‐IIA, ‐IIB, and ‐IIC) have same or differential role in bleb formation is not well understood. Here, we report that ectopically expressed GFP‐tagged NM‐II isoforms exhibit different types of membrane protrusions such as multiple blebs, lamellipodia, and combination of both or without having any protrusions in a human breast tumor cell line MCF‐7 as revealed by time lapse video microscopy. Quantification suggests that 49% of GFP‐NM‐IIA, 26% of GFP‐NM‐IIB and 19% of GFP‐NM‐IIC1 expressing MCF‐7 cells show multiple bleb formation. Interestingly, expression of phospho‐dead mutant of regulatory light chain (RLC), but not the phospho‐mimic or wild‐type, could reduce the multiple bleb formation to 8% in MCF‐7 cells. When we induce the bleb formation by disruption of cortex using 405 nm laser light, we find that all the three GFP‐tagged NM‐II isoforms can re‐appear and form filaments at different degree into the growing bleb. GFP‐NM‐IIB can form filament into the blebs in 48 % of GFP‐NM‐IIB expressing cells compared with GFP‐NM‐IIA and ‐IIC1 which form filament only in 10 % and 3 % of GFP‐NM‐IIA and GFP‐NM‐IIC1 expressing cells, respectively. These studies suggest that myosin IIs have differential role in bleb dynamics.

Source of research support:Indian Association for the Cultivation of Science, India
ARD1 controls osteoblast differentiation and bone formation as a feedback regulator of Runx2
Authors: Yoon Haejin , Park Jong‐Wan
Published: June 2021

Runt‐related transcription factor 2 (Runx2) transativates many genes required for osteoblast differentiation. The role of ARD1 (arrest defective‐1, N‐α‐acetyltransferase 10), originally identified in yeast, remains poorly understood in mammals. We here report a new ARD1 function in Runx2‐mediated osteogenesis. Runx2 stabilizes ARD1 in osteoblasts during BMP‐2‐induced differentiation, and ARD1 in turn controls this differentiation by inhibiting Runx2. ARD1 delays bone healing in a rat calvarial defect model and bone development in neonatal mice. Mechanistically, ARD1 acetylates Runx2 at Lys225, and this acetylation inhibits Runx2‐driven transcription by interfering with CBFβ binding to Runx2. Our study suggests that ARD1 acts as a guard ensuring balanced osteogenesis by fine‐tuning Runx2 signaling in a feedback manner. ARD1 inhibition could be considered a potential strategy for facilitating bone formation.
Analysis of the Family Life Surveys in Indonesia: The Contribution of Wheat Flour Fortification to Reducing Anemia
Authors: Pachon Helena , Kendrick Katherine , Codling Karen , Muslimatun Siti
Published: June 2021

Mandatory fortification of wheat flour with electrolytic iron, zinc, thiamine, riboflavin, and folic acid became effective in Indonesia in 2002. There have been no longitudinal evaluations of the effectiveness of wheat flour fortification on reducing anemia. This study estimated the contribution of wheat flour fortification to the change in anemia prevalence from the period before to after the introduction of mandatory fortification. The Indonesia Family Life Survey is a longitudinal study that followed over 30,000 Indonesians from 1993 to 2008. Data from 5,828 non‐pregnant women of child‐bearing age with hemoglobin measurements in 1997, 2000, and 2007 were analyzed. Anemia prevalence was calculated, adjusting for smoking status and altitude. Logistic regression was used to predict the effect of confounders on anemia status. Anemia prevalence significantly decreased (p<0.0001) from the pre‐fortification period during 1997‐2000 (34.0%) to the post‐fortification period in 2007 (25.2%). The main variable of interest, whether a household purchased flour‐containing foods, was not significantly associated with anemia status. Wheat flour fortification does not appear to have significantly contributed to the reduction in anemia prevalence among women of child‐bearing age in Indonesia. It is recommended that the fortification iron source be changed from electrolytic iron to a more bioavailable form and that fortification iron, zinc and folic acid levels be increased. Funding: FFI, MI, Emory, SEAMEO‐RECFON.
Amino Acids in Tanzanian Children with Sickle Cell Disease: Baseline results of the Vascular Function Intervention Trial (V‐FIT)
Authors: Marealle Alphonce , Makani Julie , Kirkham Fenella , Prentice Andrew , Cox Sharon
Published: June 2021

Poor nutritional status is common in SCD but there are no strategies to improve nutrition. Vascular function is also impaired and may underlie SCD related complications. V‐FIT (NCT01718054) is a double blind, random order, cross over trial of a daily ready‐to‐use supplementary food (RUSF) (500 kcal, 1 RDA vits & minerals, 1mg folate, Nutriset) and the same RUSF fortified with arginine & citrulline (RUSFv, 0.2g/kg/d & 0.1g/kg/d), designed to improve growth and vascular function. Here we report baseline amino acid profiles, nutritional status and their association in children enrolled in V‐FIT.

image

Methods

Children (N=119) with SCD aged 8‐11.9 y (Fig 1) were enrolled. Blood samples were collected, height, weight and whole body fat free mass (WBFFM) measured by impedance (Tanita BC418). Blood samples were processed within 2h and amino acids measured (Biochrom 30).

Results

Stunting (height for age Z score [HAZ] <‐2) and wasting (BMI for age Z score [BMIZ] <‐2) were common: 53% & 37%. Mean HAZ = ‐2.09 (SD=1.01) & BMIZ = ‐1.71 (SD=0.88). Amino acid concentrations (μmol/L) are shown in Table 1. Mean (+/‐ SD) Z‐scores compared to reference values are shown in Fig 2. Associations between amino acids and degree of stunting, wasting & WBFFM by linear regression adjusted for age & sex are shown in Table 2.

Amino acid
Mean
95% CI

tau
64.0
60.5 ‐ 67.5

thr
111.7
105.8 ‐ 117.6

ser
117.9
113.5 ‐ 122.3

glu
31.0
29.4 ‐ 32.6

gln
590.3
574.9 ‐ 605.7

pro
182.9
172.7 – 193.0

gly
269.4
258.7 ‐ 280.1

ala
281.0
265.5 ‐ 296.4

citr
28.7
23.4 ‐ 33.9

val
146.3
140.6 ‐ 152.1

cys
44.0
41.1 – 47.0

met
26.0
24.9 ‐ 27.0

ile
44.8
42.3 ‐ 47.1

leu
87.3
83.6 ‐ 90.9

tyr
67.8
65.1 ‐ 70.4

phe
51.3
49.4 ‐ 53.1

orn
75.6
65.8 ‐ 85.5

lys
112.3
105.9 ‐ 118.7

his
41.1
39.6 ‐ 42.5

arg
85.4
72.4 ‐ 98.5

adma
0.84
0.78 ‐ 0.89

image

Amino Acid
Stunting
Wasting
WBFFM

thr
r=0.012 P<0.001
‐
r=0.030 P<0.001

ser
r=0.012 P=0.001
‐
r=0.027 P=0.001

gly
r=0.002 P=0.085
r=0.003 P=0.025
r=0.009 P=0.006

ala
r=0.002 P=0.025
‐
r=0.004 P=0.043

cit

r=0.066 P=0.062

cys
‐
r=0.012 P=0.05
r=0.039 P=0.020

met
r=0.028 P=0.007
‐
r=0.073 P=0.003

ile
r=0.018 P=0.005
‐
r=0.054 P<0.001

leu
r=0.008 P=0.065
‐
r=0.025 P=0.013

orn
r=0.010 P=0.068
‐
r=0.024 P=0.068

lys
r=0.011 P<0.001
‐
r=0.025 P<0.001

his
r=0.028 P=0.002
‐
r=0.068 P=0.001

arg
r=0.012 P=0.028
‐
r=0.035 P=0.009

Conclusions

Children with SCD display amino acid profiles significantly different from reference data. Concentrations of several amino acids are positively associated with improved nutritional status.
Risk factors associated with low 25(OH)D concentrations in Kekchi‐Mayan and Garifuna adolescents from Guatemala
Authors: Bermudez Odilia , Naqvi Ali , Campos Raquel , Soto Maria , Romero Maria , Armas Laura , Solomons Noel
Published: June 2021

Objective

To assess vitamin D status and the influence of risk factors for low levels of this vitamin among Kekchi‐Mayan and Garifuna adolescents from Guatemala.

Methods: We recruited 86 adolescents, boys and girls, 43 from each ethnic group, in 2 communities from theprovince of Izabal: Kekchis from Rio Dulce, and Garifunas, of African descent, from Livingston. We obtained data on demographics plus sun protection and exposure practices. Blood samples were collected to assess 25(OH)D concentrations as nanograms per milliliter (ng/ml). Descriptive statistics were generated and regression models were tested to explain differences between groups.

Results: Mean 25(OH)D levels were 26 and 30 ng/ml (p=0.01), for Kekchis and Garifunas, respectively. 21% of Kekchis vs. 5% of Garifunas were identified as vitamin D deficient. About 51% of both ethic groups had insufficient vitamin D, while those with normal values included 28% of Kekchis and 43% of Garifunas. We found that age, being Garifuna, being male, and >2 hrs spent outside were strong predictors of Vitamin D concentrations. However, with multivariate analysis only time >2 hrs spent outside and being male were predictive of Vitamin D concentrations.

Conclusions

Despite residing in an optimal geographic location to receive adequate sunlight exposure, nearly 65% of adolescents from Kekchi and Garifuna ethnicities were either Vitamin D insufficient or deficient. This finding of low vitamin D levels in adolescents is relevant as low 25(OH)D during adolescent years has been implicated in a number of health conditions during adulthood.
An integrated agriculture, health and nutrition program increased vitamin A intakes among mothers and their infants in Western Kenya
Authors: Webb Girard Amy , Deneen Michelle , LUBOWA Abdelrahman , Okuku Haile , Low Jan , Grant Frederick
Published: June 2021

The Mama SASHA project, implemented in Western Kenya, integrated an orange‐fleshed sweet potato (OFSP)‐focused, agricultural‐nutrition education intervention into delivery of routine health services and community‐based pregnant women's clubs. The aim was to improve the diets, nutrition and health of pregnant and lactating women and their children. Multi‐pass 24 hour recalls were conducted at 8‐10 months postpartum with a subsample of 206 mother‐infant dyads enrolled from intervention and control facilities during early pregnancy; repeat recalls were conducted among 79 dyads within 1 week. Intervention effects were estimated using mixed models adjusted for clustering and confounding. The intervention was associated with significantly increased beta carotene (BC) and VA intakes (as International Units [IU] and as retinol activity equivalents [RAE]) in both mothers and infants. The odds of achieving recommended intakes and estimated average requirements for VA were significantly higher among women in the intervention group [OR (95% CI): 1.39 (1.18, 1.63) and 1.60 (1.23, 2.08), respectively] but not their infants. Maternal and infant increases in BC and VA intakes in the intervention group were attributed to OFSP consumption. An integrated agriculture‐nutrition‐health linkages project can substantially and significantly increase pro‐VA intakes and adequacy of VA intakes.
Evidence of the Effectiveness of Flour Fortification Programs on Iron Status and Anemia: A Systematic Review
Authors: Pachon Helena , Spohrer Rebecca , Mei Zuguo , Serdula Mary
Published: June 2021

The objective was to review published and grey literature on the public‐health impact of flour fortification. A systematic review was undertaken, by searching 17 databases and appealing for unpublished reports, yielding 1881 documents. Only studies on government‐supported, widely implemented fortification programs with anemia or iron outcomes measured prior to and > 12 months after initiation of fortification were included. Thirteen studies describing 26 sub‐groups (n=14 for children < 15 years, n=12 for women of reproductive age (WRA)) were analyzed. From the pre‐ to the post‐fortification periods (and as difference‐in‐difference for those that included a control group), there were statistically significant decreases in the prevalence of anemia in 4/13 studies with children and 4/12 studies with WRA and of low ferritin in 1/6 studies with children and 3/3 studies with WRA. Limited evidence suggests that when international flour fortification recommendations are followed and programs are well implemented, positive health impact is achieved.
Prevalence and Predictors of Iron Deficiency in Bolivian Infants
Authors: Burke Rachel , Revollo Rita , Iniguez Volga , Leon Juan , Suchdev Parmi
Published: June 2021

Iron deficiency (ID) in infancy can cause cognitive and developmental deficits that may be irreversible after the age of 2. The goals of this study were to quantify the prevalence of ID among 6‐month‐old infants in a high‐altitude population of Bolivia and identify modifiable risk factors of ID. Healthy infants were recruited from 2 hospitals in El Alto, Bolivia, and followed from 1 to 6 months of age. Blood taken at 6 months was analyzed for ferritin (Fer), C‐Reactive Protein (CRP), and alpha(1)‐acid‐glycoprotein (AGP). Fer values were adjusted for inflammation using internal correction factors (defined by elevated CRP and AGP), and ID was defined as corrected Fer < 12 µg/L. The following risk factors for Fer‐defined ID were initially considered: preterm birth (PTB; <37 weeks), sex, stunting (length‐for‐age Z < ‐ 2), recent diarrheal or respiratory infection, exclusive breastfeeding (EBF; defined as no complementary feeding or formula as of the 6‐month visit), maternal anemia, maternal age, maternal education, maternal employment, access to private toilet. The prevalence of ID at 6 months was 41% (67 of 163 infants assessed). Backwards elimination logistic regression identified only EBF as a significant (p < 0.05) predictor of ID at 6 months (OR: 4.7, 95% CI: 1.6 – 13.7). These results indicate that initiation of complementary feeding after 6 months (22% of this sample) increases risk of ID in this population, implying that infants may need iron supplementation prior to this time. Other interventions, such as prenatal iron supplementation and delayed cord clamping, need further exploration.
Serum cytokine levels in healthy Mongolian school‐age children randomized to either vitamin D or placebo.
Authors: Davaasambuu Ganmaa , Enkhbold Yaruuna , Boldbaatar Ninjin , Furtado Jeremy
Published: June 2021

Objective

to examine the effects of daily supplements of vitamin D on specific cytokine levels that play a role in the host inflammatory response

Methods: Double‐blinded, placebo‐controlled feasibility pilot study among120 healthy Mongolian children in Ulaanbaatar to assigned either to 800IU of vitamin D daily or identical‐looking placebo. The follow‐up was 6 months. We measured levels of 21 different cytokines (IL‐1b, 2, 4, 5, 6, 7, 8, 10, 12p70, 13, 17a, 21, 23, GM‐CSF, IFN‐γ, TNF‐α, ITAC, Fractalkine, MIP1a, MIP1b, MIP3a) in the subsamples of serum of participants at baseline and the follow‐up visit.

Results: The baseline 25(OH)D level was 7±4 ng/mL. The cytokine levels were not different between placebo group and vitamin D group at baseline. After 6 month of follow up the cytokine levels were not statistically significant except the levels of Granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) between vitamin D and Placebo group post‐treatment (p=0.03).

Conclusions

Our preliminary data show that vitamin D repletion does not change background T cell parameters in Mongolian school age children although this conclusion is limited by its small sample size and perhaps kit sensitivity issue in measuring cytokine levels in children.
Evaluation of Physical and Chemical Characteristics of Major Camel Muscles
Authors: Al‐Owaimer Abdullah
Published: June 2021

An experiment was performed to assess physical and chemical properties of ten major muscles of Arabian one‐humped camel. Eight young (8‐10 months) Saudi Najdi camels were used for this purpose. The animals were raised under similar feeding regimen and husbandry practices for 60 days. After that, they were slaughtered, dressed and kept for 24 hrs at 4º C. Then, each carcass was split into two halves and twelve major muscles were removed from the right side of the carcass. These are Semitendinosus, Rectus femoris, Biceps femoris, Infraspinatus, Gluteus medius, Semimembranosus, Supraspinatus, Psoas major, Longissimus lumborum and Longissimus thoracis. The separated muscles were cut into steaks of 2.5 cm, packaged under vacuum and stored at – 10º C for later analysis. These included pH, color, cooking loss (CL), shear force (SF), and myofibril fragmentation index (MFI). The results showed that Psoas major and Supraspinatus had the lowest SF values (P< 0.05), while Semitendonosus had the highest value. Gluteus medius and Longissimus thoracis obtained the highest MFI values (P< 0.05), contrary, Rectus femoris had the lowest value. It is observed that Semitendonosus and Longissimus thoracis had the highest lightness value (L*), whereas Infraspinatus had the lowest. On the other hand, Semitendonosus and Supraspinatus had the highest numerical redness value (a*), while Rectus femoris had the lowest value. The results obtained out of this study shed light on the variation in some chemical and physical properties of camel muscles which in turn lay a basis for further investigations to improve quality characteristics of camel meat.

Physical and chemical characteristics of ten major camel muscles

Muscle
SF (kg)
MFI
CL%
pH
L*
a*
b*

Semitendinosus
5.4a
34.52bcd
42.61a
5.23cd
37.48a
16.67ab
5.45a

Rectus femoris
5.06ab
26.14d
34.53bc
5.42a
35.03bcd
4.32cd
4.32cd

Gluteun medius
4.88ab
56.40ac
40.45ab
4.26ac
32.96ef
15.90abc
5.03bc

Biceps femoris
4.81ab
41.50abcd
36.03abc
5.19c
33.11def
14.39cd
4.88bcd

Longissimus lumborum
4.77ab
36.72bcd
36.49abc
5.26bc
35.78ab
14.48cd
4.66bed

Longissimus thoracis
4.67abc
51.10ab
41.26ab
5.22cd
36.23ab
14.15cd
4.48cd

Infraspinatus
4.3c
44.62abcd
39.72abc
5.45ab
32.16f
15.41bd
4.55cd

Semimembranosus
3.81cd
37.5abcd
33.69bc
5.35ab
34.41bcde
14.16cd
5.32b

Supraspinatus
3.56d
46.52abc
38.81abc
5.43a
33.33cdef
17.52a
5.03bc

Psoas major
3.41d
48.77abc
37.13abc
5.22cd
35.19bd
15.58bc
4.96bed

abcdef Means in the same column followed by different subscripts are significantly different at P < 0.05
Effect of Gynura procumbens Water Extract on Enzymes Activities Related with Glucose Metabolism in HepG2 Cell
Authors: kim Dae Jung , Kang Yun Hwan , Kim Tae Woo , Kim Kyoung Kon , Choe Myeon
Published: June 2021

Gynura procumbens, fast growing herbaceous plant, is widely found in Africa and South‐ East Asia, especially Indonesia, Malaysia, and Thailand, and extensively used in folk medicines as remedy for eruptive fevers, rash, kidney diseases, and hypertension. The present study was designed to investigate the antidiabetic effect of Gynura procumbens water extract (GWE) by regulation of activities of hepatic glucose‐regulating enzymes, such as glucokinase (GK), pyruvate dehydrogenase (PDH), ATP‐citrate lyase (ACL) and glycogen synthase kinase‐3beta (GSK‐3β). GK and PDH activity in HepG2 cells were determined by enzyme activity assay kit. Protein expression of ACL and pGSK‐3β in HepG2 cells were detected by western blotting. Because of α‐glucosidase enzymes metabolize non‐absorbable oligosaccharides into absorbable monosaccharides, α‐glucosidase inhibitor is usually used to prevent and treat type II diabetes; thus, evaluated for inhibitory effects of GWE against α‐glucosidase.

GK (3.0 fold), PDH (1.4 fold) activities were significantly (p<0.05) increased compared with the control. pACL (3.4 fold) and pGSK‐3β (1.5 fold) protein expression were significantly higher than control. Compared to the anti‐diabetic drug acarbose, which was used as a positive control, GWE exhibited high α‐glucosidase inhibition activity (32.2% in 3mg/ml). Take together, our suggest that GWE exerted antihyperglycemic potency, is thought to be mediated through activation of GK, PDH and induction of protein expression of pACL, pGSK‐3β related to glucose metabolism directly or indirectly.
Factors Associated with Meeting Public Health Recommendations for Beverage Intake in Young Children
Authors: Mesa Tatiana , Wright Julie , Lindsay Ana
Published: June 2021

Objective

To examine factors associated with meeting public health recommendations for the consumption of various beverages: no sugary drinks (SSB), 4‐6 ounces/day 100% fruit juice (FJ), and 2.5 cups/day of milk.

Methods:

A survey study of 203 parents or legal guardians who identified as a primary care giver of a child between the ages 4‐10 years of age. Questions included the amount of beverages consumed on a typical day. Backward stepwise logistic regression (WALD) was used to examine factors associated with meeting the recommendations. Factors entered were race (non‐hispanic white v. non‐hispanic black), household income (蠄40K v. >40K), marital status (not married v. married), and child age (4‐5 v. 6‐10 yrs).

Results:

Of the 203 parents, 52% Black, 88% female, 51% 蠄 40K, 43% married, mean age 38.6 (8.1) yrs, and mean child age 7 (2.1) yrs. For FJ, 49% met the recommendation. Whites were 2.4 times more likely to report meeting the recommendation than blacks (95% CI = 1.2 ‐ 4.7, p=.01) and high income was 2.6 times more likely than low income (95% CI =1.3 ‐ 5.2, p = .006). For SSB, 27% met the recommendation, but only marital status was a significant covariate (OR, 2.43, 95% CI = 1.2 ‐ 5.0, p= .02). For milk, 89% met the recommendation, but only child age was a significant covariate (OR, 2.57, 95% CI = 1.0 ‐ 6.4, p= .04).

Conclusion

The results highlight a disparity in meeting recommendations for limiting 100% FJ with race and income being significant factors. The results for SSB suggest that single parents struggle more with limiting sugary drinks. Further analyses should examine factors within these disparity groups to understand how to develop interventions that help promote a healthful intake of beverages.