bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Hepatic Progenitor Cells in Hepatic Fibrosis of Elderly Cadavers: Cytokeratin 7 Marks Intermediate Hepatocyte‐Like Cells
Authors: Mak Ki M , Png Chien Yi M
Published: November 2023

Human hepatic progenitor cells (HPCs) are small oval‐shaped cytokeratin (CK) 7 and CK19 expressing cells that normally reside in a quiescent state in the canals of Hering. In response to liver damage, as in alcoholic liver disease, nonalcoholic fatty liver disease, viral hepatitis, and chronic cholestasis, the HPCs become activated. Being bipotential cells, HPCs can differentiate into either cholangiocytes or hepatocytes; the latter occurs via intermediate hepatocyte‐like cells (IHLCs). IHLCs are polygonal in shape with a size intermediate between HPCs and hepatocytes and express phenotypic markers for biliary lineage and hepatocytic lineage. It has been reported in baboons chronically fed alcohol that an increased number of CK7 immunoreactive IHLCs correlated with the progression to more severe stages of liver fibrosis; CK19 immunoreactive IHLCs, however, were not observed. Since elderly cadavers with diverse causes of death demonstrated progressive stages of liver fibrosis (Mak et al., 2012, Anat Rec 295:40–50), the present study evaluated whether CK7 served as a marker for IHLCs of elderly cadavers. To that end, consecutive paraffin liver sections from embalmed cadavers were immunoperoxidase stained using monoclonal CK7 and CK19 antibodies, in conjunction with EDTA‐based antigen unmasking. For assessment of fibrosis, sections were post‐stained with Sirius red stain for collagens. HPCs were detected by the CK7 or CK19 staining of the cytoplasm, whereas IHLCs were identified by a distinct CK7 staining of the cell membranes and a faint staining of the cytoplasm. In livers with minimal fibrosis, while IHLCs were not observed, CK7 and CK19 positive HPCs were present in both the periportal and lobular parenchyma. However, in livers with perisinusoidal fibrosis, IHLCs were occasionally detectable in foci showing parenchymal fibrosis. In septal fibrosis, IHLCs were readily found, along with CK7 positive HPCs, in close proximity to the developing septa and linking septa. In cirrhosis, there were variable numbers of CK7 stained IHLCs in the parenchyma of the nodules. In striking contrast, CK19 immunoreactive IHLCs were rare or undetectable in any of the abovementioned locations.

Conclusions

as in alcoholic fibrosis of baboons, CK7, but not CK19, serves as a marker for IHLCs in liver fibrosis of elderly cadavers. Since IHLCs have the potential to differentiate into hepatocytes, their development in liver fibrosis points to a link between IHLCs and hepatic regeneration consequent to chronic liver injury in the aged cadaveric liver.
Innervation of the Female Levator Ani Muscle and Consequences in Pelvic Floor Dysfunctions
Authors: Bessede Thomas , Timoh Krystel Nyangoh , Lebacle Cedric , Martinovic Jelena , Zaitouna Mazen , Diallo Djibril , Creze Maud , Benoit Gerard , Moszkowicz David
Published: November 2023

Introduction

The Levator Ani Muscle (LAM) and the Levator Ani Nerve (LAN) are distended and traumatized during pregnancy and vaginal delivery. Both mechanisms may sustainably impair the pelvis statics but the topography and functions of the nerve supply to the LAM remain anatomically controversial.

Objective

To characterize the nature and function of the LAM nerve pathways and to perform a comprehensive 3D reconstruction of the female pelvic innervation.

Methods

The Computer‐Assisted Anatomical dissection (CAAD) protocol was applied to pelvic blocks procured in 6 female human fetuses, in accordance with the National Biomedicine Agency. Specimens were serially sectioned and immunostained for: overall (S100), somatic (PMP22), adrenergic (TH), cholinergic (VaCHT) and nitrergic (nNOS) nerve fibers and for: smooth (smooth actin) and striated (myogenin) muscle fibers. Slides were digitized for 3D reconstructions on WinSurf®. A pelvic sample of an additional fetus was examined under electronic microscopy to analyze the ultrastructure of the LAM.

Results

Three main nerve pathways to the LAM were observed: the levator ani nerve (LAN), the pudendal nerve (PuN), the inferior hypogastric plexus (IHP). The PuN was both somatic and autonomic, located below the LAM (‘infralevator pathway’) and supplying innervation to the inferior aspect of the LAM. The LAN was solely somatic, located above the LAM (‘supralevator pathway’) and supplying innervation to the superior aspect of the LAM. The IHP nerve fibers were solely autonomic, located in between the LAM and the pelvic organs (‘endolevator pathway’) and supplying innervation to the medial portion of the LAM. Smooth muscle areas were identified with labelings and electronic microscopy: they 1) were located in the puboanal sling of the LAM 2) were bulging between rectum and vagina 3) were intermingled to the anococcygeal raphe 4) were innervated by the IHP and the PuN pathways.

Conclusion

Having at once striated and smooth muscle fibers and being co‐innervated by the somatic and autonomic systems, the LAM represents a crucial anatomical structure involved in the pelvic floor function and its rehabilitation.

Support or Funding Information

none
Systematic Studies of Effects of the Discriminator on Stabilization of the Open Complex and Abortive and Productive Initiation
Authors: Felth Lindsey , Molzahn Cristen , Wang Si , Henderson Kate , Ruff Emily , Poulos Mikaela , Chhabra Munish , Bieter Lauren , Artsimovitch Irina , Record M. Thomas
Published: November 2023

E. coli RNA polymerase (RNAP) is a large molecular machine (subunits: αββ′ω and specificity factor σ70) with many moving parts that binds to and opens duplex promoter DNA to initiate transcription. These events are set in motion by initial interactions between σ70 and the −35 and −10 elements of the promoter, and between the flexibly tethered α‐CTDs and the UP element of the promoter. Binding free energy drives a series of conformational changes that culminate in opening of 13 base pairs between the −10 region and the start site, forming an initial unstable open complex, which is stabilized at some promoters by a network of interactions involving the discriminator and σ70 region 1 in the cleft, and between the downstream duplex and downstream mobile elements (DME) of RNAP. Different promoter open complexes differ greatly in lifetime: the open complex at the rrnB P1 ribosomal promoter is very short‐lived (~1 s), as compared to 6 minutes for T7A1, and 17 hours for λPR promoter. To investigate effects of discriminator sequence and length on the structure, lifetime and function of the open complex, we are exchanging discriminator regions between promoters and determining KMnO4 reactivities of open thymine bases, dissociation rate constants and patterns of abortive and productive initation using a common initial transcribed sequence. We extend previous findings by observing that the discriminator can be the primary sequence determinant of open complex lifetime; for example, inserting the T7A1 or rrnB P1 discriminator into λPR reduces its lifetime nearly to that of these promoters, while inserting the λPR discriminator into T7A1 increases its lifetime nearly to that of λPR. Footprinting reveals that template strand thymines upstream of the start site in the longer lived complexes have greater KMnO4 reactivity. To interpret this, we propose that RNAP binds the phosphate backbone of this strand; tighter binding unstacks the bases more, as shown for SSB‐ssDNA by Lohman, and hence increases their KMnO4 reactivity. To address the question of how the discriminator sequence and open complex lifetime affect abortive and productive initiation, we are conducting single round transcription assays on series of promoters differing only in the discriminator region. For the λPR series of discriminator variants, reproducible differences are observed in the amounts and pattern of both short and long products. Currently, research is focused on variants that exchange the λPR WT discriminator with those of rrnBP1 and T7A1 to determine how the discriminator region affects the distribution of short and long products as well as the absolute amount of products produced.
Transcriptome profiles of porcine skin dyschromia after wound injury
Authors: Alkhalil Abdulnaser , Muhie Seid , Carney Bonnie , Travis Taryn E , Moffatt Lauren , Johnson Laura , Ramella‐Roman Jessica , Shupp Jeffrey
Published: November 2023

Dyspigmentation after cutaneous injury negatively impacts patients’ self esteem and social reintegration. Most patients with deep surgical wounds or full thickness burns develop dyspigmented scar tissue which is more salient among people with dark colored skin. Although the pigment synthesis cascade in healthy tissue has been characterized, our understanding of the causative biological perturbations leading to skin dyspigmentation after injury is limited. Consequently, therapies are partially effective, and often invasive and inconvenient. We have adapted a genome‐wide approach to profile the difference in the transcriptomes of hyper‐ and hypo‐pigmented skin obtained from a porcine scar animal model after full thickness wound injury. The results showed significant differences in several genes of chromia including those encoding the DOPA chrome tautomerase (DCT), tyrosinase (TYR), tyrosinase related protein 1 (TYRP‐1), endothelin receptor type B (ENDRB), melanocortin 1 receptor (MC1R) and microphthalmia transcription factor (MITF). Other genes related to melanosome biogenesis such as members of the solute carrier family SLC24A5 and SLC52 A4 and related isotypes including SLC25A19, SLC25A36, SLC35D1, SLC35F5, SLC37A1, SLC52A2 were differentially transcribed. Molecules affecting cell‐matrix and cell‐cell binding showed significant modulations. The Ingenuity pathway analysis revealed the significant alterations to the melanin synthesis pathway and other pathways that indirectly influence melanin synthesis included the Ras signaling and the Wnt/B catanine pathways. The enrichment of several modified biological processes to melanocytes highlights the susceptibility of these cells to the negative impact of deep wounds and worse outcome.

Support or Funding Information

This work was funded by the NIH grant No. 1R15EB013439
Sifting through the Haystack to Find the Needle: Spatial Identification of a Structural Conduit for Transfer of Thermal Activation Energy in the Course of C‐H Cleavage in Soybean Lipoxygenase
Authors: Offenbacher Adam , Hu Shenshen , Nguy Andy , Iavarone Anthony , Klinman Judith
Published: November 2023

Protein motions are increasingly recognized as an important facet for the huge rate accelerations achieved by enzymes. The ability to link specific protein fluctuations to the chemical step(s) of catalysis remains a daunting challenge. The importance of room temperature hydrogen tunneling in C‐H activation, where the hydrogenic wave function overlap itself is temperature independent, makes such reactions ideal for identifying the thermally activated protein motions that comprise the reaction barrier. We present a thorough examination, involving time, temperature and mutation dependence of the hydrogen deuterium exchange (HDX) behavior of a large, single polypeptide protein, soybean lipoxygenase (SLO‐1), which has emerged as the paradigm tunneling enzyme. By incorporating mutation‐induced packing defects previously shown to selectively impair deuterium over protium tunneling, we first confirm previously proposed changes in active site flexibility as the origin of increases in the temperature dependence of kinetic isotope effects. This approach also identifies a remote surface loop, located approximately 15–40 Å from the active site, whose motions respond to the temperature of the solvent in a manner similar to catalysis. A network that connects this loop to the reactive iron center is identified and concluded to act as a conduit for the funneling of kinetic energy from solvent to the enzyme active site. Our ongoing work is taking advantage of thiol‐based labeling approaches to selectively position chromophores onto the surface loop, to monitor the protein motions and their interactions with solvent molecules in real time from picosecond to microsecond timescales.

Support or Funding Information

Supported by a grant from the National Institutes of Health, GM025765 (J.K.) and 1F32GM113432 (A.O.)
Effect of Immobilization on the Stability and Specificity of Choline Oxidase
Authors: Schmitz Jonathan Michael , Watkins Linette
Published: November 2023

Choline oxidase catalyzes the conversion of choline into glycine betaine and hydrogen peroxide. Choline oxidase has two roles in industry and medicine, as a sensor of choline, and in the synthesis of glycine betaine. For optimal utility in industrial synthesis pathways, choline oxidase must have a broad specificity while maintaining activity over a range of pH and temperature. The specificity, pH optimum, temperature stability, of choline oxidase from three different sources was determined. In order to address low stability at elevated temperatures, choline oxidase was immobilized on CNBr‐activated Sepharose beads. Immobilized choline oxidase showed enhanced stability over a broader range of temperature and pH. Preliminary data suggests that immobilized choline oxidase has reduced specificity for choline and other quaternary ammonium salts. New methods for testing specificity to confirm this preliminary data are under investigation.
ETV5, an Ets Family Transcription Factor, is a Marker for RAS‐Dependent Papillary Thyroid Cancer
Authors: Hoang Nguyet Minh , Puli Oorvashi Roy , Danysh Brian , Hofmann Marie Claude
Published: November 2023

Introduction

BRAF V600E mutation has a significant association with recurrence in patients with papillary thyroid cancer, reducing survival rate from 98% to 40%. Patients treated with BRAF V600E inhibitors such as vemurafenib acquire resistance to the drug over time (6 months) and tumor cells metastasize to distant organs, leading to patient death. Within the group of patients with BRAFV600E tumors, there are no reliable biomarkers to predict local or distant recurrences, especially when tumors acquire clonal resistance due to the effects of targeted therapies. PTC (Papillary Thyroid Cancer) patients with the BRAF V600E and RAS mutations show an elevated ETV5 (Ets‐transcript variant 5) expression. ETV5, a transcription factor, is known to promote epithelial to mesenchymal transition (EMT) in endometrial carcinomas and ovarian cancer by up‐regulating ZEB1, a repressor of E‐Cadherin, causing cell detachment and invasion. ETV5 also induces the expression of matrix metalloproteinase 2 (MMP‐2) in human endometrial carcinomas, causing invasion.

Hypothesis

We hypothesize that ETV5 drives cell proliferation and EMT (Epithelial to Mesenchymal Transition) in advanced papillary thyroid cancer.

Methods

We used the cell line KTC1 (BRAF V600E mutant thyroid cancer cell line) as a model. ETV5 and BRAF V600E were knocked‐down using Silencer Select siRNA. Alternatively, cells were treated with standard pharmacological inhibitors (i.e. PI3Ki, AKTi, vemurafenib, ERKi, TGFBR1i). ETV5 expression was quantified using Quantitative PCR and Western Blots. Proliferation/growth assays were performed for 5 days and the cell numbers were counted using the IN Cell 6000 confocal system and Image Analysis software post‐transfection/treatment.

Results

Knockdown of ETV5 and/or BRAF decreased KTC1 cell proliferation. Cell growth was reduced upon treatment with vemurafenib, or PI3K‐AKT and ERK inhibitors, but not with TGFBR1 inhibitors. In comparison to DMSO treatment (control), ETV5 levels were down‐regulated upon ERK inhibitor treatment but were increased when treated with PI3K inhibitors. Short‐term vemurafenib treatment (48h) showed a reduction in ETV5, N‐Cadherin, and CXCR4 expression suggesting its role in EMT.

Conclusion

ETV5 acts downstream of the RAS‐MAPK (ERK1/2) pathway. ETV5 is crucial for KTC1 cell proliferation and may also play a role in EMT in PTC.

Support or Funding Information

This project is sponsored by a DRP grant, which is part of NIH P50 CA168505
Effects of TCTP Over‐expression in Bacteria
Authors: Parmar Nitika
Published: November 2023

TCTP (Tumor protein, translationally‐controlled 1) has been implicated in many cellular functions that are related to growth. TCTP has been shown to interact with the G‐protein Rheb, a key player of the PI3 Kinase/mTOR signal transduction pathway and thought to function as its GEF (Guanine Nucleotide Exchange Factor). This study was designed to understand the effects and role of TCTP in prokaryotic physiology. Although no homologs of TCTP have been found in prokaryotes, the expression of wild type and a mutant version of mammalian TCTP on bacterial metabolism under stress conditions was investigated. Wild type mammalian TCTP coding sequence was cloned in a bacterial expression vector and expressed in E. coli under an inducible promoter. Recombinant protein expression was confirmed via polyacrylamide gel electrophoresis and immunoblotting. The impact of TCTP on bacterial growth characteristics in rich and synthetic media was studied under a variety of stress conditions including heat stress, with temperatures ranging from 37–55°C; oxidative stress using hydrogen peroxide; osmotic stress using NaCl; nutrient stress using nutrient depleted medium and pH stress. A mutant version of the protein was made using random mutagenesis and studied as well. Expression of TCTP rendered the cells more sensitive to temperature, pH and oxidative stress. Significant differences were observed with regard to the growth profiles and sensitivity to these stresses when TCTP expression was induced. While the wild type version rendered the cells sensitive at 37°C, 45°C and 50°C, the mutant version rescued this phenotype. H2O2 exposure led to sensitivity by both versions. At alkaline pH (10, 11), cell death was observed in cells expressing TCTP but not in controls. These results indicate that TCTP may play an important role in bacterial growth under stress conditions and although this protein is a mammalian protein, this study provides evidence that it is influencing the metabolic profile of bacteria. TCTP over‐expression in bacteria causes significant changes in physiological responses and may provide useful insights into its role in mammalian physiology.

Support or Funding Information

This work was supported by a CSUCI Faculty Development Minigrant and a UNIV498 award to Nitika Parmar.
Phosphodiesterase 3B (PDE3B) Regulates NLRP3 Inflammasome and Metabolic Cross Talk in Adipose Tissue
Authors: Khan Faiyaz Ahmad , Chung Youn Wook , Tang Yan , Hockman Steven C , Liu Steve , Khan Yusuf , Huo Kevin , Amar Marcelo J , Remaley Alan T , Manganiello Vincent C
Published: November 2023

Activation of inflammation in white adipose tissue (WAT) which includes infiltration/expansion of WAT macrophages contributes to pathogenesis of obesity, insulin resistance, type 2 diabetes, and metabolic syndrome. The inflammasome protein complex comprises an intracellular sensor (typically a Nod‐like receptor, NLR), caspase‐1 (a cysteine protease) and the adaptor ASC (apoptosis‐associated speck‐like protein). Inflammasome activation leads to the maturation of caspase‐1 and processing of IL1β contributing to many metabolic disorders and directing adipocytes to a more insulin‐resistant phenotype. Ablation of PDE3B in SVJ129 mice epididymal white adipose tissue (EWAT) prevents inflammasome activation by reducing the expressions of NLRP3, caspase‐1, ASC, interferon‐inducible protein AIM2, TNFα, IL1β and proinflammatory genes (i.e, cyclooxygenase2). Following IP (intraperitoneal) injection of lipopolysaccharide (LPS), serum levels of IL1β and TNFα were reduced in PDE3B−/− mice compared to WT. Moreover, chemokine (C‐C motif) ligand 2 (CCL2)/monocyte chemotactic protein‐1 (MCP‐1) and its receptor CCR2, which play an important role in the macrophage chemotaxis, were less highly expressed in EWAT of PDE3B−/− mice. In addition, atherosclerotic plaque formation was significantly reduced in the aorta of apoE−/−/PDE3B−/− and LDL‐R−/−/PDE3B−/− mice compared to apoE−/− and LDL‐R−/− mice, respectively. Collectively, these data establish a role for PDE3B in modulating the inflammatory response which may contribute to the decreased inflammatory state and reduced aortic plaque formation in PDE3B−/− mice.

Support or Funding Information

Supported by the NHLBI Intramural Research Program
Investigation of a Mitochondrial Twin Arginine Transport Pathway in Arabidopsis thaliana
Authors: Weerakoon Tasmeen Shiny , Ma Qianqian , Dabney‐Smith Carole
Published: November 2023

Most proteins are synthesized at a location different to their site of function. For example, most of the proteins found in cell organelles such as mitochondria or chloroplasts are encoded by nuclear genes, which are transcribed in the nucleus and translated in the cytoplasm. Cells therefore, must have efficient protein transport processes to allow proteins to cross membranes such as those bounding cell organelles like mitochondria or chloroplasts. Proteins destined for organelles are synthesized as larger molecular weight precursors, containing targeting sequences, which direct the precursor to the appropriate transport apparatus at the membrane.

One such vital protein transport pathway is the Tat (Twin Arginine Translocation) pathway. The Tat pathway has been found in a wide variety of organisms including bacteria, archaea and eukaryotic organelles such as the chloroplast. The chloroplast Tat pathway (or analogous Tat pathways in bacteria) is capable of transporting fully folded proteins across membranes using only a proton motive force instead of ATP for energy. It is composed of three protein components, namely cpTatC (TatC), Tha4 (TatA) and Hcf106 (TatB) that work together to allow the transport of precursor proteins containing an obligate twin arginine motif in the targeting sequence.

However, recent experiments using Nicotiana tabacum cells showed an up‐regulation of a mitochondrial gene coding for a mtTatC protein when the cells was subjected to salicylic acid treatment, which mimics a defense response in the plant to attack by pests. However, single nuclear genes encode both of the other Tat components. Analogous transport pathways in certain Gram (+) bacteria demonstrate that a minimal functional Tat pathway is composed of TatC and TatA (Tha4 homologue). We have confirmed a similar upregulation under stress of salicylic acid of the putative mitochondrial tatC gene in Arabidopsis thaliana. The presence and upregulation under stress of the mttatC gene suggests the possible presence of a mitochondrial Tat pathway, which would require the dual localization of a TatA homology, such as Tha4.

To test the possible dual localization of Tha4 to mitochondrial, we have transformed Arabidopsis thaliana with Tha4‐GFP constructs and looked for its localization in the presence or absence of various biotic or abiotic stresses. In addition, we will look at changes in gene expression using RT‐PCR technique to look for Tha4 upregulation in the presence or absence of the stress.

Evaluating the presence of a mitochondrial Tat pathway will shed light on a unique protein sorting and transport mechanism in plant mitochondria, a facility previously thought to be lost during the mitochondrial evolutionary process. Therefore investigating this protein sorting pathway in mitochondria may further our understanding of acquired innate immunity within flowering plant species.
Enhancement of Folate Levels in Lettuce via a Methylotrophic Symbiont
Authors: DeMell April , Holland Mark
Published: November 2023

Pink‐Pigmented Facultatively Methylotrophic (PPFM) bacteria are distributed ubiquitously in the phyllosphere of plants where they participate in a unique symbiotic relationship. By utilizing methanol released by the plant as a carbon source, they secrete compounds that increase plant growth and yield. Previous research has shown that plants, such as lettuce (Lactuca sativa), hosting mutant PPFMs that overexpress and secrete specific metabolites, such as vitamin B12 and methionine, accumulate these metabolites in their foliage and seeds. We have selected folate overproducing PPFMs on the basis of their resistance to the antifolate methotrexate. Their capability to over secrete folate will be tested by their ability to rescue a folate auxotroph (Bacillus subtilis BKE0070). Levels of folate production will be determined by microbial or ELISA assay. We expect that bacterization of seeds with our folate overproducing and secreting mutants will result in folate enriched lettuce leaves. Folate is essential in the diets of humans for critical cellular pathways, such as DNA replication, and influences the uptake of other metabolically important B vitamins. If folate accumulation in lettuce leaves is successful, future experiments will be repeated on the agriculturally significant legume, Glycine max (soybean).
Evaluating Programmatic Effectiveness and Implementation: An Assessment of Factors Affecting Change in the Practice of Exclusive Breastfeeding in Ethiopia and Mali
Authors: Baxter Jo‐Anna B , Barac Raluca , Davidson Marnie , Salim Laila , Zlotkin Stanley , Barwick Melanie
Published: November 2023

Exclusive breastfeeding (EBF) to six months of age is one of the most effective interventions to ensure the survival of newborns and children, yet programmatic activities implemented to increase EBF rates are only variably successful. With funding from the Canadian government's Muskoka Initiative Partnership Program, two NGOs (CARE and Save the Children) implemented programs in Ethiopia and Mali to improve maternal, newborn, and child health outcomes, including EBF. Programmatic activities were diverse, including the development of educational material, community‐based counselling, radio messaging, and mother‐to‐mother support groups. This study aimed to quantitatively assess the observed change in EBF coverage from cross‐sectional survey data, and qualitatively determine contextual factors that influenced the implementation of EBF programmes from focus group discussions (n=15; included mothers and community leaders) and key informant interviews (n=17; included government officials and NGO personnel). Baseline and endline data showed a net increase in the EBF rate in both countries (Mali: 27.3% [95% CI: 19.2 to 35.3] to 66.3% [95% CI: 57.0 to 75.7], P<0.05; Ethiopia: 69.4% [95% CI: 62.4 to 76.3] to 75.1% [95% CI: 69.9 to 80.3], not significant). When analyzed inductively (themes identified from the qualitative data) and deductively (categories assigned to the qualitative data from an existing framework), some of the most influential factors that emerged for EBF adoption were engaging influential community members as ‘champions’ for change; repeated exposure to information about EBF practice and benefits; exposure to community members’ EBF testimonials; and community recognition of a strong need for change to improve infant health outcomes. Traditional beliefs, knowledge, and practices regarding infant feeding and gender role‐related expectations were also found to be important factors for EBF behavioural change. Ultimately, the identified factors for successful implementation and uptake of EBF activities will help to guide and refine existing implementation frameworks, as well as programmatic approaches to increase the number of mothers who practice EBF.

Support or Funding Information

Financial support was provided by the Government of Canada through Foreign Affairs, Trade, and Development Canada (DFATD).
Body Image Perceptions and Breastfeeding Practices among HIV‐Positive Malawian Women with Young Children
Authors: Croffut Samantha , Hamela Gloria , Mofolo Innocent , Hosseinipour Mina , Hoffman Irving , Maman Suzanne , Bentley Margaret , Flax Valerie
Published: November 2023

Before the prevention of mother‐to‐child transmission (PMTCT) program was widely implemented in Malawi, HIV‐positive women were concerned that exclusive breastfeeding could accelerate disease progression and felt that an HIV‐positive woman could more successfully breastfeed if she had a larger body size. Body image perceptions and their relationship to breastfeeding practices have not been explored in the context of the current Option B+ PMTCT program, which offers lifelong antiretroviral therapy and recommends exclusive breastfeeding for 6 months and continued breastfeeding for 24 months. To fill this gap, we conducted in‐depth interviews with 32 HIV‐positive women enrolled in PMTCT and 32 HIV‐positive women who had dropped out of the PMTCT program in Lilongwe District, Malawi. Interview guides included questions about current, preferred, and healthy body size perceptions using nine body‐image silhouettes, ranging from very thin to obese. We also used narrative scenarios to elicit discussion of the breastfeeding practices of two fictitious HIV‐positive women with different body sizes. More than 80% of participants preferred an overweight (67%), obese (11%), or morbidly obese (3%) figure, and about half of participants selected a morbidly obese figure as healthy. Participants described their preference for overweight figures as having “good health status” and obese figures as “looking good.” No significant differences were found between PMTCT and defaulter participant perceptions of body size. While about half of participants thought that an HIV‐positive woman who was underweight would be able to breastfeed, nearly all participants believed that an HIV‐positive woman who was overweight would be able to breastfeed. One participant described an underweight woman's inability to exclusively breastfeed, “She will grow thin, worse than she looks now.” Another participant stated that an overweight woman will be able to exclusively breastfeed because “she has a strong, fresh body.” In conclusion, among HIV‐positive women, the preference for overweight and obese body figures may be related to fears that underweight women are unable to breastfeed. The consistency of our findings with those from the pre‐PMTCT era indicate a strong cultural preference for large female body size, perhaps because of the perception that it facilitates breastfeeding. In light of evidence from the Demographic and Health Survey of the increasing prevalence of overweight and obesity among Malawian women, including those who are HIV‐positive, we recommend that counseling and health education for Malawian women focus on messaging around a healthy weight range and its relationship with breastfeeding practices.

Support or Funding Information

NIH BIRCWH K12 program, UNC CFAR developmental award
Implementation of an Integral Health Program to Control Parameters Associated with Childhood Obesity
Authors: Valenzuela‐Rubio Nancy Guadalupe , Ochoa‐Acosta Dora Alicia , Magaña‐Gomez Javier Abednego , Castro‐Acosta Monica , Vergara‐Jimenez Marcela
Published: November 2023

Childhood obesity has been increasing worldwide and is considered an important public health problem. There are several strategies addressed to control obesity in children. The objective of this study was to compare the effect of an Integral Health Program (IHP) to improve parameters associated with obesity in children in two different time interventions and to measure their impact in the adherence to the program as a life style. 77 overweight or obese scholars were recruited (8,11y), they were randomly assigned into two groups (A, 37 and B, 40). Both groups were divided in two stages, stage 1 for intervention and stage 2 for adherence. During stage 1 both groups received an IHP, which consisted in receiving hypocaloric diets, nutritional education, physical activity sessions and ludic activities. Group A had a two months intervention and Group B a three months. Adherence was measured during the consecutive six months after the intervention. Anthropometric variables, nutritional education status, eating behavior indicators were measured during the study. During the intervention, SDS‐BMI was significantly reduced in both groups (A+B), 2.73±0.12 at the baseline and 2.38±0.12 (p<0.05) by the end of the intervention, however there were not significant differences between individual groups. Similar was in the Waist‐Height Radio from 0.59±0.008 to 0.55±0.008 (p<0.001) and body fat from 36.70±0.92 to 33.44±0.92 (p<0.05). Nutrition knowledge significantly increased in A+B after the intervention from 65.27±1.68 to 73.35±1.68 (p<0.05). Body fat was significantly reduced in group B compared to group A (11.8±1.97 versus 5.8±1.82, p<0.05). All the changes observed during the intervention stage, were maintained during the follow up period (adherence). Both groups improve their food choices, however Group B had better results than group A. We concluded that the implementation of an IHP improve the body composition and other important parameters associated with the development of obesity in children.
Effect of Vitamin D3 Supplementation on Telomerase Activity in Hispanics with Type 2 Diabetes
Authors: Zarini Gustavo G. , McLean Michael , Vaccaro Joan , Exebio Joel , Ajabshir Sahar , Huffman Fatma G.
Published: November 2023

Significance

Low levels of telomerase activity create short telomeres, which in turn signal exit from the cell cycle, cell senescence and apoptosis. Low telomerase activity and short telomere length are linked to type 2 diabetes and mortality. Hispanics are shown to have shorter telomere lengths as compared to Whites. Hispanics are also at high risk for type 2 diabetes and vitamin D deficiency.

Objective

This study investigated whether daily vitamin D3 supplementation at 4000 IU can increase telomerase activity over time in Hispanics with type 2 diabetes and hypovitaminosis D (25‐hydroxy vitamin D < 30 ng/mL).

Methods

Participants (n=34) were recruited from two clinics in Miami‐Dade County, FL, US (Borinquen Health Care Center and Clinical Care Medical Center). Twenty milliliters of venous blood (at least 8 hours fasting) was collected from each participant by a certified phlebotomist using standard laboratory methods. Serum 25‐hydroxy vitamin D levels were determined using a commercial ELISA kit from Immunodiagnostic Systems Limited (Scottsdale, AZ, USA). Telomerase activity was assayed by the TeloTAGGG Telomerase PCR ELISA kit (Roche Applied Science, Indianapolis, IN, USA). Final quantified telomerase activity levels were expressed as Relative Telomerase Activities (RTA). Participants were given 4000 IU/day of vitamin D3 supplementation for 6 months. All data analyses were conducted on an “intent to treat” basis. Statistical analysis included descriptive statistics and one‐way repeated‐measures ANOVA.

Results

Mean levels for telomerase activity differed statistically significantly between time points (F(2,66) = 78.57), p < 0.001). Post hoc test using Bonferroni correction indicated that telomerase activity levels increased from baseline to 6 months (49.3 ± 6.8 vs. 63.1 ± 7.2 RTA, respectively) which was statistically significant (p < 0.001). However, baseline to 3 months telomerase activity levels (49.3 ± 6.8 vs. 45.9 ± 3.9 RTA, respectively) were not statistically significant (p = 0.068).

Conclusion

Vitamin D3 supplementation at 4000 IU/day significantly increased telomerase activity in Hispanics with type 2 diabetes. Vitamin D3 supplementation may prevent/delay disease progression in type 2 diabetes through telomerase re‐activation and maintenance of DNA. Larger randomized controlled trials are needed to confirm these results in this and other racial/ethnic groups.
Milk Proteins and Amino Acids Modulate Inflammatory Gene Expression in Vascular Endothelial Cells
Authors: Da Silva Marine S , Bigo Cyril , Barbier Olivier , Rudkowska Iwona
Published: November 2023

The digestion of milk proteins releases bioactive peptides and amino acids which may be beneficial for cardiovascular protection. However, mechanisms underlying the lowering effect of milk proteins on systemic inflammation, a cardiovascular disease (CVD) risk factor, remain to be elucidated.

Objective

To investigate the effect of milk proteins and their major amino acid components on inflammatory gene expression in vitro.

Methods

Human umbilical vein endothelial cells (HUVEC), stimulated or not with TNFα to trigger inflammation, were incubated for 24h with 1‐ milk proteins: whey protein (0.5 or 5 mg/ml); isolate (WPI) or hydrolysate ((WPH) a mixture of bioactive peptides and amino acids); caseins (CN, 1 mg/ml); a mixture of WPI and CN (WPCN, 1:4 w/w); or 2‐ amino acids (0.2–20 mM): branched‐chain amino acids ((BCAA) including leucine, isoleucine and valine), glutamine or proline. Expression of pro‐inflammatory genes TNF and VCAM‐1 was measured by RT‐PCR.

Results

WPI caused a down‐regulation of the two pro‐inflammatory genes, whereas WPH and its major BCAA, leucine and isoleucine, had no effect in unstimulated cells. Furthermore in these cells, both CN and WPCN decreased VCAM‐1 expression; however, TNF expression was increased by the mixture WPCN. Glutamine‐ the major amino acid of CN, and valine‐ a BCAA found in both milk proteins, up‐regulated the pro‐inflammatory genes in unstimulated cells. Stimulation of HUVEC with TNFα caused increased expression of TNF and VCAM‐1. This effect was partially inhibited by WPH and the three BCAA; whereas WPI had no effect in stimulated cells. In addition, CN and WPCN lowered VCAM‐1 together with an increased TNF gene expression in stimulated cells. Glutamine increased VCAM‐1 expression in stimulated cells. Proline had no effects.

Conclusion

Whey proteins (WPI and WPH) and BCAA exerted anti‐inflammatory effects; whereas CN, the mixture WPCN and glutamine showed pro‐inflammatory properties according to the inflammatory state of endothelial cells. These results support the potential of whey proteins for CVD prevention.
Sex Differences in the Responses of Gut Microbiome to Long‐term Dietary Selenium Deprivation and Aging in Short Telomere Mice
Authors: Lu Hsin‐Yi , Wu Ryan T.Y. , Cheng Wen‐Hsing
Published: November 2023

How sex, dietary selenium (Se) and aging interact and affect mammalian gut microbiome is not known. Here, we sequenced bacterial 16S ribosomal RNA libraries prepared from feces of male and female Terc−/− short telomere mice at 18 and 24 months of age on a Se‐deficient or –adequate (0.15 ppm Se as sodium selenate) diet since weanling. Results from principle coordination analysis demonstrated that the taxonomic composition and the abundance of selective genus of gut microbiome and ratios of Firmicutes/Bacteroidetes changed by age and dietary Se deprivation, but not sex. In addition, the microbial alpha biodiversity was assessed by a nonparametric Shannon index that represents within‐subject variations at species level. While Shannon index was increased as a result of the dietary Se deprivation and aging in the males, such within‐subject variations by Se deprivation and aging were decreased in the females. Taken together, sex affects changes of gut microbiome by dietary Se deprivation and age in short telomere mice.
The Effects of Folate Deficiency and Arsenic Exposure on Thymidylate Synthesis in Serine Hydroxymethyltransferase 1‐Deficient Mouse Embryonic Fibroblasts
Authors: DiRisio Aislyn , Kamynina Elena , Field Martha S. , Stover Patrick J.
Published: November 2023

Low maternal folate is associated with the failure of the neural tube to close during development, leading to a class of developmental anomalies referred to as Neural Tube Defects (NTDs). NTDs are observed in mouse embryos with impaired de novo thymidylate (dTMP) biosynthesis resulting from decreased SHMT1 expression when the mother is fed a folate‐deficient diet. 5,10‐methylenetetrahydrofolate is a cofactor for thymidylate synthase (TYMS) in the conversion of deoxyuridylate (dUMP) to dTMP via one‐carbon metabolism. De novo thymidylate synthesis is critical to prevent uracil misincoporation, which can lead to double strand breaks (DSBs). Tetrahydrofolate (THF) is converted into 5,10‐methyleneTHF by serine hydroxymethyltransferase 1 and 2 (SHMT1, SHMT2) and the methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) at the replication fork. Arsenic is also shown to induce NTDs in animal models. Reduced SHMT1, SHMT2, and MTHFD1 expression, either alone or in combination, lead to a greater extent of γH2AX phosphorylation in HeLa cells, indicating that these proteins contribute to genomic stability. Additionally, we observed that As2O3 exposure increased genome instability and changed the distribution of cells across the cell cycle in HeLa cells. Here, we present the extent of DNA DSBs, apoptosis, and p53 expression in mouse embryonic fibroblasts in response to arsenic exposure and folate deficiency. Shmt1 −/− MEFs were isolated from embryos derived from dams fed either a folate‐deficient or control diet and cultured in folate‐replete or folate‐depleted media with or without 5μM As2O3. Folate deficiency and As2O3 exposure result in the formation of DNA DSBs, with the greatest effect seen with folate deficiency and As2O3 exposure in combination. These data indicate that folate deficiency and As2O3 exposure affect genome stability in SHMT1‐deficient MEFs.

Support or Funding Information

Public Health Services grant HD059120
The Impact of Lipid‐Based Nutrient Supplements on Maternal Depression at 6 mo Postpartum in Ghana: A Randomized‐Controlled Trial
Authors: Okronipa Harriet Eyram T. , Adu‐Afarwuah Seth , Lartey Anna , Ashorn Per , Vosti Steva A. , Young Rebecca Tree , Dewey Kathryn G.
Published: November 2023

Background

Maternal postpartum depression (PPD) has been reported to affect 13% of women globally and has been linked to poor child health. Poor maternal nutrition, including low dietary intake of essential fatty acids, may be a risk factor for PPD.

Objective

We examined the impact on depression at 6 months postpartum of maternal supplementation with lipid‐based nutrient supplement (LNS) compared to supplementation with iron and folic acid (IFA) or multiple micronutrients (MMN).

Method

In this partially double‐blinded randomized controlled trial, pregnant women ≤20 wk gestation (n=1320) were randomly assigned to receive either 1) LNS during pregnancy and for 6 months postpartum, or 2) IFA during pregnancy only, or 3) MMN during pregnancy and for 6 months postpartum. Maternal depressive symptoms were measured at 6 mo postpartum using the Edinburgh Postnatal Depression Scale (EPDS). Women who scored 12 or more on the EPDS were considered to show symptoms of depression.

Results

1151 women were included in this analysis (LNS=382, IFA=387 and MMN=382). Characteristics of the three groups were similar at baseline and there were no significant differences between women who were included in the analysis (n=1151) and those who were not (n=169). At 6 months postpartum, 13% of women overall showed symptoms of depression, and this did not differ by group (LNS=13.3%, IFA = 10.6% and MMN = 14.4%. P=0.36). The median (25, 75 percentile) EPDS scores did not differ by group (LNS 4.0 (1.0, 8.0), IFA 4.0 (1.0, 8.0), MMN 5.0 (2.0, 9.0), Ptransformed =0.13). Season of depression data collection was a significant effect modifier for depression scores (P=0.02): in women assessed during the dry (post‐harvest) season, the LNS group compared to the MMN group had lower EPDS scores (P=0.015).

Conclusion

Maternal supplementation with LNS compared to MMN or IFA did not affect postnatal depressive symptoms in this sample of Ghanaian women. However the lower depression scores in the LNS group among those evaluated during the dry season warrants further investigation.

Support or Funding Information

This study was funded by a grant from the Bill & Melinda Gates Foundation to the University of California, Davis, USA
Effects of Chromium Supplements on Wound Healing
Authors: White Pandora E. , Chen Tsung‐Sheng , Chen Yi‐Ting , Liu Chia‐Hsin , Sun Chi‐Ching , Vincent John B. , Mao Frank Chiahung , Lee Wei‐Ming
Published: November 2023

Glucocorticoids, such as dexamethasone, are anti‐inflammatory drugs that are used to treat inflammatory conditions such as arthritis. However, over time the constant use of anti‐inflammatory drugs impairs wound healing. Insulin like growth factor (IGF‐1) plays a role in promoting wound healing. Cr(III) has been proposed to enhance levels of IGF‐1 and increase wound healing. CrCl3 has previously been shown to improve wound healing in animals receiving dexamethasone. The specific objective of this study was to test the ability of various Cr(III) compounds to enhance wound healing in C57BL6/JNarl mice. Wounds were inflicted on mice and then Cr(III) compounds were administered to see if wound healing was accelerated in mice receiving dexamethasone. The results indicate that the Cr(III) compounds did not significantly enhance wound healing.

Support or Funding Information

Funding was provided by the Ministry of Science of Taiwan, the National Science Foundation East Asia and Pacific Summer Institute, and Maxluck Biotechnology Corporation.
Blueberry Supplementation Alters Biomarkers of Oxidative Stress in High‐fat Fed Rats
Authors: Keirsey Katherine I , Lee Sunhye , de La Serre Claire B , Fischer Joan G
Published: November 2023

Obesity is associated with enhanced inflammation and oxidative stress. Blueberries contain high levels of anthocyanins, which may mitigate oxidative stress through direct antioxidant activity and/or alterations to antioxidant enzyme activities. Our objective was to determine if blueberry supplementation would decrease systemic, hepatic, and colonic oxidative stress in high fat fed rats. Wistar rats (n= 8/group) were fed low‐fat (LF, 10% fat), high‐fat (HF, 45% fat) or high‐fat with 10% blueberry (HF_BB) diets for 8 wks. HF and HF_BB diets were isocaloric and all diets were matched for sugar and fiber content. Levels of urinary F2‐isoprostanes, a marker of systemic lipid peroxidation, and hepatic and colonic malondialdehyde (MDA) were assessed. Activities of glutathione peroxidase (GPx) and glutathione reductase (GR), antioxidant enzymes that may be altered by anthocyanins, were also measured in liver. Unexpectedly, blueberry supplementation resulted in a small but significant increase in urinary F2‐isoprostanes in high fat fed rats. Hepatic MDA was elevated by HF feeding but was significantly lower in HF_BB fed animals compared to HF fed animals. Blueberry supplementation did not enhance hepatic GPx or GR activities, suggesting these enzymes did not account for the reduction in hepatic MDA. Although colonic MDA was lower in HF_BB animals compared to HF animals, the difference was not significant. These results suggest that blueberry supplementation may alter oxidative stress in high fat fed animals in a tissue‐specific manner.

Support or Funding Information

This material is based on work that is supported by the National Institute of Food and Agriculture, USDA, under award number 2014‐67017‐21757 & GA Agricultural Experiment Station.