bluuebunny/crossref_metadata_2025 huggingface dataset:
Dairy Product Intake is Associated with Cognition but not Cognitive Decline in the NuAge Community‐Dwelling Older Adult Cohort
Authors: Tessier Anne‐Julie , Farsijani Samaneh , Payette Hélène , Morais José A. , Gaudreau Pierrette , Shatenstein Bryna , Chevalier Stéphanie
Published: November 2023

Background

Dairy products (DP) may exert a role in cognition, possibly through their content in bioactive peptides, vitamin B12, calcium and fermented products. Sparse evidence from cohort studies has related total DP intake to cognitive status, but its impact on age‐related cognitive decline remains unknown.

Objective

To study associations between total daily intake of DP, high‐fat (HF) and low‐fat (LF) DP, DP categories, and cognition at baseline (T1) and as a 3 y‐change in community‐dwelling older adults.

Methods

Analyses were conducted on 702 men and 797 women of the Quebec longitudinal study on nutrition and aging (NuAge) aged 67–84 y at T1. Yearly average total dairy intake was calculated from averaging 3 non‐consecutive 24‐h food recalls collected at T1 and 3 at T3. Number of DP servings was calculated as per Canadian Food Guide portion sizes. Cognitive function was assessed yearly by the Modified Mini‐Mental Examination State (3MS). Baseline cross‐sectional associations were estimated using multivariate regression models adjusted for sex, age, education, symptoms of depression (GDS) and global diet quality (Canadian‐Healthy Eating Index, C‐HEI). Longitudinal associations were investigated using linear mixed models over 3 years.

Results

Baseline 3MS score was 93.2 ± 4.6 in men and 94.6 ± 4.1 in women (p<0.001), and total dairy intake 1.43± 0.84 and 1.38 ± 0.76 servings/d (p=NS). Over 3 years, the 3MS score decreased by 2.2 ± 5.5% (p<0.001) with a greater decline in men (2.6 ± 5.5%) than women (1.9 ± 5.4%; p<0.001). At baseline, total dairy intake was associated with 3MS score (std β=0.181, p<0.001) in the whole cohort. Though the level of education was the main determinant of 3MS, the association with dairy remained significant in a multivariate model including all predictors (R2=0.241). The relationship was also observed in both men and women separately. Among DPs, milk, yogurt, cheese as well as HF and LF dairy intake were associated with baseline 3MS score but only cheese or HF dairy intake remained significant predictors after adjustments (std β=0.055, p=0.018, R2=0.240). Usual total dairy intake was not associated with the rate of cognitive decline over 3 years.

Conclusions

Total dairy, especially HF dairy, were independently and cross‐sectionally associated with cognition, providing further evidence in this novel area. Since full fat cheese largely contributed to HF dairy intake, cheese‐specific nutrients including fatty acids point to potential unique mechanisms in cognitive function. The absence of an association between dairy intake and cognitive decline may be explained by the modest 3‐year decline in this healthy cohort. Longer follow‐up investigation of distinct cognitive domains, and in cognitively impaired older adults, is warranted.

Support or Funding Information

Dairy Farmers of Canada
The Combinatory Effects of Diet and Exercise on BDNF Gene Expression
Authors: Zeeni Nadine , Haidar Edwina Abou , Azar Adriana , Ghanem Anthony , Bassil Katherine , Bassil Maya , Sleiman Sama
Published: November 2023

Brain Derived Neurotrophic Factor (BDNF) plays a critical role in the synaptic activity and plasticity of mature neurons and regulates the formation and maintenance of memory. Furthermore, human and mouse BDNF levels were found to be altered in psychiatric diseases. Actually, BDNF signaling not only contributes to the pathophysiology of depression, but also is important for the therapeutic effects of antidepressants. On the other hand, exercise induces beneficial responses in the brain, many of which are mediated through induction of BDNF expression. Moreover, BDNF expression was shown to be enhanced under select dietary conditions. However the exact mechanisms for these inductions have been elusive. The aim of the present work was to explore the effect of combining different diets with exercise on BDNF expression in the brain.

First, C57BL/6 mice were divided into 6 groups based on the diet they received (standard versus high protein versus high fat) and whether they were provided with a running wheel to exercise during 28 days or not. Results showed that high protein diets induced BDNF expression and that combining this diet with voluntary exercise had an additive effect on BDNF expression. In contrast, a high fat diet attenuated the positive effects of exercise on BDNF expression.

In a second experiment, the effect of dietary leucine (1.5% or 3%) was tested in mice exposed to the same 28‐day voluntary exercise paradigm as the first experiment. Results showed that supplementation with 1.5% leucine significantly induced BDNF in the brain, and this effect was additive with exercise as well. Future work will investigate whether the effect found is restricted to leucine or may be extended to other branched chain amino acids such as isoleucine or valine.

The present results enrich our understanding of how exercise and different diets coordinate to induce BDNF gene expression and may be used in identifying novel therapeutic targets for depression.
Low Serum Retinol Concentration Explain Higher Hepcidin Levels In Mexican Older Adults
Authors: De la Cruz‐Góngora Vanessa , Salinas‐Rodríguez Aarón , Villalpando Salvador
Published: November 2023

Background

Elevated hepcidin levels have been linked to anemia of inflammation (AI). Retinol deficiency has shown to modulate hepcidin expression in animals; however, no studies have explored low serum retinol (LSR) concentration in older adults (OA) and their possible association with hepcidin concentrations. Anemia affect 27% of Mexican OA and inflammation may play a role in the production of anemia in this population. Understanding the mechanisms that play a role in the control hepcidin secretion is an important goal in the prevention of AI.

Aim

To explore if low serum retinol is associated with higher serum hepcidin concentrations in Mexican older adults (≥60years).

Methods

Mexican OA were participants in a crossectional study to identify the main causes of anemia. They were recruited in August 2015. Fasting serum samples were collected in 535 OA. Serum retinol (SR) was measured by HPLC and LSR was defined if SR<20μg/dL. Hepcidin (ng/mL) was measured using a commercial ELISA kit. Due to skewed distribution of hepcidin, a quantil regression model was used to associate the LSR and hepcidin, adjusting by sex, age, BMI, ferritin, transferrin receptor, vitamin B12 status, IL‐6, C reactive protein, Alpha‐1‐acid glycoprotein, diabetes, hypertension, tertil of socioeconomic status, sarcopenia and functional disability.

Results

Mean age was 71.5y for male and 70.7y for female. LSR was present in 3.2% of OA. Mexican OA with low serum retinol had 12.2 ng/mL higher hepcidin levels than OA with normal serum retinol levels (p=0.03). Hepcidin adjusted median (by confounders) were (median±EE): 19.4± 1.0 ng/mL in OA with normal serum retinol and 31.9±5.7 ng/mL in OA with LSR. Sarcopenic OA had higher hepcidin levels (coef: 7.5 ng/mL, p=0.03) than OA non‐sarcopenic.

Conclusions

LSR levels in OA explain their higher hepcidin concentrations. Retinol concentrations affects iron homeostasis but the mechanism is unclear. This data document for the first time that in humans, low serum retinol concentration is inversely associated with hepcidin concentrations. Further longitudinal studies are needed to understand the role of serum hepcidin and Retinol in the development of AI in OA.

Support or Funding Information

CONACYT‐FONSEC SSA/IMSS/ISSSTE SALUD 2014‐1, S0008‐2014‐1‐000000000234157
Brain Plasticity: Measuring Protein Synthesis Rates in the Human Brain
Authors: Smeets Joey S.J. , Horstman Astrid M.H. , Schijns Olaf E.M.G. , Dings Jim T.A. , Hoogland Govert , Gijsen Annemie P. , Goessens Joy P.B. , van Loon Luc J.C.
Published: November 2023

Introduction

Brain plasticity is a term typically used to refer to the ability of the brain to reorganize itself throughout life. Though the term is often applied in neuroscience to express synaptic or non‐synaptic plasticity, information on whether neuroplasticity is also accompanied by a high brain tissue protein turnover rate is scarce. Because of obvious limitations with regard to brain tissue sampling no study has ever directly measured brain protein synthesis rates in vivo in humans. In this study, we applied contemporary stable isotope methodology to assess protein synthesis rates in vivo in human brain tissue of patients operated for drug‐resistant epilepsy.

Methods

Six otherwise healthy patients (47±6 y), scheduled to undergo resective surgery for treatment of drug‐resistant temporomesial epilepsy, were included in this study. Primed continuous intravenous infusions with L‐[ring‐13C6]‐Phenylalanine and L‐[3,5‐2H2]‐Tyrosine were initiated 2.5 h prior to surgery and continued during surgery. Throughout the surgical procedure the following tissue samples were obtained: temporal neocortex, hippocampus, temporalis muscle, and vastus lateralis muscle. Tissue‐specific fractional protein synthesis rates (%/h) were assessed by measuring the incorporation of labelled L‐[ring‐13C6]‐Phenylalanine in tissue protein and were compared between the different tissues using a paired t test.

Results

Serum L‐[ring‐13C6]‐Phenylalanine enrichments averaged 8.1±0.7 MPE throughout the surgical procedure. Protein synthesis rates of temporal neocortex and hippocampus tissue averaged 0.17±0.01 and 0.13±0.01 %/h, respectively, with a significant difference between both tissues (P<0.05). Brain tissue protein synthesis rates were 3–4 fold higher compared to skeletal muscle protein synthesis rates (0.05±0.01 %/h; P<0.001).

Conclusion

This is the first study to present protein synthesis rates in vivo in the human brain. With brain protein synthesis rates being several‐fold higher compared to skeletal muscle protein synthesis rates, the human brain displays a degree of tissue plasticity much higher than generally assumed.
Effect of Gastric By‐pass on Dietary Protein Bioavailability and Protein Anabolism in Rats
Authors: Gaudichon Claire , Tessier Romain , Ribeiro‐Parenti Lara , Bruneau Ouafa , Cavin Jean‐Baptiste , Khodorova Nadezda , Bado André , Tomé Daniel , Le Gall Maude
Published: November 2023

Introduction

Bariatric surgery is an efficient treatment of massive obesity but it can trigger nutritional deficiencies, especially regarding vitamins and proteins. Protein wasting may be observed although there are large prevalence variations in the literature. Additionally to a low protein intake, protein malabsorption logically appears as a risk factor of protein wasting. However, there is little data on protein digestion after bariatric surgery. Our study aimed to assess the effect of gastric‐bypass (RYGB) on dietary protein bioavailability and protein status in rats.

Methods

Rats were fed for 3 months an obesogenic diet. Eighteen rats underwent RYGB surgery (survival: n=9) and 10 Sham (survival: n=10) served as control that were pair‐fed. For 15 d post‐surgery, dietary intake, weight and body composition were measured. After 15 d, rats were given a test meal containing 15N labeled proteins. They were sacrificed 6 h after the meal and dietary proteins were quantified in gastrointestinal segments (stomach, duodenum, jejunum, ileum, caecum and colon) by elemental analyzer coupled to isotope ratio mass spectrometer. Small intestine morphology was studied by histology. The protein Fractional Synthesis Rate (FSR) was measured in the liver, kidney, muscle and skin using a 13C valine flooding dose before sacrifice. Results (means ± SEM) were analyzed using a t test (P<0.05).

Results

Compared to baseline, RYGB decreased dietary intake by 49%. Despite pair‐feeding, weight loss was higher in RYGB than in Sham (14±2 % vs 7±0.8 %, P= 0.002), as well as fat mass loss (33±5 % vs 20±1 %, P=0.03). Lean mass loss was 7±1.5 %. in both groups. Six hours after the meal test, there was more dietary nitrogen in the caecum of Sham than RYGB but no difference was detected in other intestinal segments. Real protein digestibility was lower in Sham than RYGB (93.1±0.6 % vs 95.2±0.7%, P=0.03). Histology revealed a hypertrophy of jejunum mucosa in RYGB. The FSR of kidney protein was strongly decreased (P<0.001) in RYGB (72.2±3.2 %/j) compared to sham (98.4±3.3 %/j). Protein anabolism was similar between groups in other tissues.

Conclusion

We showed that dietary protein bioavailability was paradoxically improved in RYGB, an effect that can be attributed to the jejunum mucosa hypertrophy. We also revealed that RYGB markedly lowered protein anabolism in the kidney. It will be interesting to identify which protein are involved in this effect.
Aloe‐emodin attenuates inflammatory signaling cascade in Pam3CSK4‐stimulated macrophages
Authors: Park Mi‐Young , Kim Soon‐Kyung
Published: November 2023

Aloe‐emodin (AE) is an ingredient of aloe and is known to exhibit anti‐inflammatory activities. However, little is known about underlying molecular mechanisms of inflammatory modulation in vitro. In the present study, we investigated the anti‐inflammatory potential of AE using Pam3CSK4‐stimulated macrophages. RAW 264.7 macrophages was treated with AE (0–20 mM) for 1 h followed by Pam3CSK4 for 1 h, and then the mRNA expression levels of cytokines were measured. The effect of AE on the TLR2‐related molecules was also investigated in Pam3CSK4‐stimulated RAW264.7 macrophages. AE attenuated Pam3CSK4‐stimulated expression of proinflammatory cytokines, including tumor necrosis factor‐α (TNF‐α), interleukin‐6 (IL‐6), and interleukin‐1β (IL‐1β) in both RAW264.7 macrophages and DMEMs. AE showed reduction on mRNA levels of toll‐like receptor 2 (TLR2) and on activation of the nuclear factor‐kappa B (NF‐κB) and mitogen‐activated protein kinase (MAPK) phosphorylation. Our data suggest that AE exerts its anti‐inflammatory effect by suppressing the TLR2‐mediated of NF‐κB and MAPK signaling pathways in macrophages.

Support or Funding Information

This study was supported by Soonchunhyang University Research Fund.
Dietary Patterns and Lung Function: Assessment of the Alternative Health Eating Index‐2010 (AHEI‐2010) and Rate of Change in Forced Expiratory Volume in the First Second (FEV1)
Authors: Rettig Samantha A. , Xu Jiayi , Karr Alexandra R. , Tang Wenbo , Guertin Kristin A. , Goodman Phyllis J. , Minasian Lori M. , Lippman Scott M. , Klein Eric A. , Cassano Patricia A.
Published: November 2023

Objective

Prior studies of diet and lung function focus on individual nutrients or foods, whereas US Dietary Guidelines focus on dietary patterns. We investigated the association of the Alternative Healthy Eating Index‐2010 (AHEI‐2010), a measure of overall dietary quality and compliance to the US dietary guidelines, and lung function, quantified by the rate of change in forced expiratory volume in the first second (FEV1).

Methods

The Respiratory Ancillary Study (RAS; N=2,920), which was nested within SELECT (Selenium and Vitamin E Cancer Prevention Trial), studied the effect of supplementation with vitamin E and selenium on the longitudinal trajectory in lung function. RAS also assessed usual dietary intake with a food frequency questionnaire (FFQ) at study baseline; the current analysis investigated the AHEI‐2010 score (higher score indicates greater compliance to dietary guidelines), derived from the FFQ, in relation to rate of change in FEV1. Linear mixed‐effects models estimated the AHEI‐2010—rate of change in FEV1 association, with AHEI‐2010 as a continuous variable (null hypothesis β=0). Models were adjusted for race, age, height, weight, smoking status and pack‐years, education, marital status, residence status, treatment arm, multivitamin use, and energy intake, and extended to test the AHEI‐2010 score × smoking interaction.

Results

A higher AHEI‐2010 score was associated with a slower rate of decline in FEV1 across the full cohort such that an increase of 10 (~1SD) in AHEI‐2010 was associated with a 7.0 mL/year attenuation in the rate of decline (P=0.0009). Models confirmed a statistically significant interaction of AHEI‐2010 and smoking status (P=0.0278), which indicated a stronger association of AHEI‐2010—rate of decline in FEV1 in current smokers compared to never/former smokers. In current smokers, an increase of 10 (~1SD) in AHEI‐2010 was associated with a 17 mL/year attenuation in the annual decline in FEV1 (95% CI: 7, 26); in never/former smokers the same increase in AHEI‐2010 was associated with a 5mL/year (95% CI: 0.4, 9) attenuation in rate of decline.

Conclusions

In a population of North American men, a higher AHEI‐2010 score was associated with a slower decline in lung function, and the association was 3‐fold stronger in current smokers compared to never/former smokers. Translating this to dietary intake, in smoking men consuming one additional serving of vegetables or fruit/day (i.e., increase of 2 in AHEI‐2010), the annual rate of decline in FEV1 was attenuated by 3.3 mL/year.

Support or Funding Information

Funding: NHLBI R01HL071022 (PAC), and, in part, by NCI U10CA37429 and 5UM1CA182883
Prospective Evaluation of Fat Intake and Risk of Skin Cancer
Authors: Park Min Kyung , Li Wen‐Qing Kyung , Li Tricia , Qureshi Abrar A , Cho Eunyoung
Published: November 2023

Fat intake has been examined in many studies for its associations with incident cancer such as colorectal, breast, and prostate cancers. In particular, polyunsaturated fat may have anti‐inflammatory functions that protect against ultraviolet radiation damage. However, previous literature on dietary fat and skin cancer has been conflicting and few prospective studies were available. Therefore, we examined the associations between consumption of fat and risk of incident skin cancer including cutaneous malignant melanoma, squamous cell cancer (SCC), and basal cell carcinoma (BCC) within two prospective studies; the Nurses' Health Study (NHS) and the Health Professionals Follow‐up Study (HPFS). Dietary information on fat intake including total fat, saturated fat, monounsaturated fat, polyunsaturated fat, cholesterol, trans fat, and omega‐3 fat was repeatedly assessed every 4 years with a validated food frequency questionnaire during follow‐up. Incident skin cancer cases were identified through self‐report and diagnosis on melanoma and SCC were confirmed by reviewing pathologic records. A total of 794 melanoma, 2223 SCC, and 17556 BCC cases in the NHS (1984 to 2012) and 722 melanoma, 1704 SCC, and 12756 BCC cases in the HPFS (1986 to 2012) were documented during the follow‐up. None of the fats were associated with melanoma. However, we found higher risk of SCC in the highest category of polyunsaturated fat intake (HR, 1.23; 95% confidence interval (CI), 1.05–1.44; P trend=0.01) in NHS and lower risk of SCC in the highest category of cholesterol intake (HR, 0.77; 95% CI, 0.66–0.91; P trend=0.01) in HPFS compared to the lowest categories of intake. For BCC, intakes of total fat (HR, 0.90; 95% CI, 0.85–0.96), saturated fat (HR, 0.85; 95% CI, 0.79–0.90), and monounsaturated fat (HR, 0.90; 95% CI, 0.79–0.90) were each associated with lower risk of BCC in HPFS, but not in NHS. Intake of omega‐3 fat were associated with higher risk of BCC in NHS (HR, 1.10; 95% CI, 1.05–1.16) and HPFS (HR, 1.09; 95% CI, 1.03–1.16) with significant trends (p<0.001), respectively. In conclusion, there was no association between fat intake and risk of melanoma in the two prospective studies. We found inconsistent associations of fat intake with SCC and BCC, except for omega‐3 fat and BCC. Further studies are needed to provide clear guidelines for fat intake and skin cancer.
Feasibility and Reliability of The Monell Forced Choice Test to Measure Sweet Taste Preference in Ghanaian Children Aged 4–6 y
Authors: Okronipa Harriet , Arimond Mary , Arnold Charles D. , Adu‐Afarwuah Seth , Tamakloe Solace M. , Young Rebecca Tree , Dewey Kathryn
Published: November 2023

Introduction and objective

Little or no research involving the measurement of sweet taste preference in children has been done in a developing country setting. In a randomized controlled trial to examine the efficacy of small‐quantity lipid‐based nutrient supplements (LNS) for supporting healthy growth and development, infants received 0 g or 20 g daily SQ‐LNS from 6–18 months of age. The SQ‐LNS was moderately sweet, with 4 g of total sugars per daily dose, including lactose (in milk) and sucrose. As part of a follow‐up aiming to assess impact on subsequent sweet taste preference, we tested the feasibility and reliability of the Monell forced choice taste test to measure sweet taste preference among Ghanaian children aged 4–6 y.

Methods

A total of 598 children were recruited and taken through the 2‐series taste test. Each series included a number of forced choices between two concentrations of sucrose in water, one lower and one higher, across a range of 3 – 36% w/v concentrations. Each child tasted two solutions and was asked to point to the one they preferred. Choices continued at varying concentrations until a single preferred concentration was identified. In the first series the less sweet solution was always tasted first, and in the second the sweeter solution was tasted first. Reliability was assessed by calculating the percent agreement between the first and second series.

Results

The test required an average of 3.8 and 3.7 presentations of sucrose solution pairs for series 1 and 2, respectively. About 47% chose the same or next closest sucrose concentration in series 1 and 2, and 38% chose > 2 concentrations higher/lower. Child age (P<0.001) but not level of schooling (P=0.4601) was associated with the percent agreement between series 1 and 2. Compared to children who were 6 y old at the time of testing, children aged 4 y [OR (95% CI): 5.96 (2.04, 17.45)] and 5 y [3.05 (1.03, 9.00)] were more likely to prefer > 2 concentrations higher/lower in series 1 versus 2.

Conclusion

In our setting and possibly other low income settings similar to our study area, the Monell forced choice test is feasible but may be acceptably reliable only among children aged 6 y and above.

Support or Funding Information

This study was funded by a grant from the Bill & Melinda Gates Foundation to the University of California, Davis, USA.
Lycopene protects kidney against atrazine‐induced oxidative stress and autophagy via activating the AMPK pathway
Authors: Lin Jia , Xia Jun , Li Xue‐Nan , Zhang Cong , Li Wei , Li Jin‐Long
Published: November 2023

The environmental persistence and bioaccumulation of herbicide atrazine (ATR) may pose a significant threat to human health, especially causing nephritic dysfunction. Lycopene (LYC) has been shown to exhibit nephritic disease preventive effects. However, chemopreventive potential of LYC against ATR‐induced nephrotoxicity remains unclear. To determine the effects of ATR and/or LYC on kidney, mice were treated with ATR (50 mg/kg or 200 mg/kg) and/or LYC (5 mg/kg) by intragastric administration for 21 days. The results revealed that ATR led to increased serum creatinine content and significantly histological alterations. Notably, supplementary LYC significantly decreased ATR and its main metabolites (DACT) contents. LYC administration reverted ATR‐induced dysregulation of oxidative stress markers including pancreatic malondialdehyde, hydrogen peroxide and redox enzymes superoxide dismutase, glutathione peroxidase and catalase. LYC treatment downregulated ATR‐induced increase of nuclear factor erythroid 2‐related factor 2 (Nrf2) expression and Nrf2‐regulated redox genes including quinoneoxidoreductase‐1, heme oxidase‐1. In addition, LYC suppressed ATR‐induced activation of autophagy containing LC3II/LC3I, ATGs, Belin1, p62, in parallel with increased AMPK activation. Together, our findings demonstrate that LYC suppresses the expression of antioxidant enzymes and p62 by activating Nrf2 signaling pathway, then stimulating AMPK pathway to resist ATR‐induced renal oxidative stress and autophagy.

Support or Funding Information

China New Century Excellent Talents in University (No. NECT‐1207‐02), National Natural Science Foundation of China (No. 31572586) and Academic Backbone Project of Northeast Agricultural University (No. 15XG16).
CDK 7/9 inhibition amplifies mithramycin's suppression of Ewing sarcoma cell proliferation
Authors: Flores Guillermo , Everett Joel , Osgood Christy , Madaj Zachary , Grohar Patrick J
Published: November 2023

Background

Ewing sarcoma is driven by the fusion of the EWSR1 and FLI1 genes generated by a t(11:22) chromosomal translocation. Ewing sarcoma cells depend on the EWS‐FLI1 fusion product, a constitutively active oncogenic transcription factor, and become nonviable when EWS‐FLI1 driven transcription is inhibited. Mithramycin, a natural antineoplastic compound, has been identified as a potent EWS‐FLI1 inhibitor and is highly toxic to Ewing sarcoma cells. However, clinical trials of mithramycin in patients with Ewing sarcoma have been limited due to toxicity. To overcome this challenge, we sought to identify genes that sensitize Ewing sarcoma cells to mithramycin when inhibited. We identified RNA pol II inhibition as a potent sensitizer to mithramycin and phenocopied this with the dual cyclin dependent kinase (CDK) 7/9 inhibitors PHA‐767491 and SNS‐032. We show a marked suppression of cellular proliferation in response to mithramycin in combination with either CDK 7/9 inhibitor at concentrations significantly lower than mithramycin alone.

Methods

We utilized matrix drug screening with small molecule CDK inhibitors in combination with mithramycin. We measured cell viability using MTS assays and time lapse microscopy in Ewing sarcoma cells. Results were correlated with EWS‐FLI1 activity using western blot analyses and qPCR. Synergy between small molecule inhibitors and mithramycin was measured using Bliss independence.

Results

PHA‐767491 and SNS‐032 displayed strong synergy when combined with mithramycin. These combinations decreased the concentration of mithramycin necessary to block Ewing sarcoma cell proliferation, measured by multiple complementary assays. These results reflected effects on EWS‐FLI1 activity.

Conclusions

We have identified a synergistic relationship between the small molecules PHA‐767491 and SNS‐032 with mithramycin in Ewing sarcoma cells. Future work will include siRNA validation of the CDK 7/9 inhibition and mithramycin combination, analysis of genome wide expression changes, and characterization of the efficacy of a PHA‐767491 or SNS‐032 and mithramycin drug combination in vivo with the eventual goal of introducing it into the clinic.
The Role of Scleraxis in Neutrophil Activation
Authors: Awotunde Olanike , Nillas Andrea , Hammad Samar , Reaves Titus A.
Published: November 2023

Scleraxis is a transcription factor in the basic helix loop helix (BHLH) family, and originally shown to regulate embryonic tissue into tendon and endothelium in blood vessels. More recently scleraxis has been linked to activation of fibroblasts and cardiac fibrosis. Organ fibrosis follows inflammation and is characterized by dysregulated and excessive production/release of extracellular matrix proteins—principally collagen. Within fibrotic organs there are a variety of immune cells. In particular, polymorphonuclear leukocytes (PMN) are components of the innate immune system and are first responder cells present in high numbers in organs undergoing fibrosis. PMN have two basic functions, they migrate to areas of inflammation/injury and destroy pathogenic organisms. Activated PMN release myeloperoxidase ((MPO), heme protease that is toxic to pathogens and is dependent on the leukocyte specific integrin CD11b) from their primary granules. We hypothesize that scleraxis is involved in the activation of PMN. Immunocytochemistry, flow cytometry, and Western blot analysis shows that PMN express scleraxis. Antibodies against scleraxis had minimal effects on cell attachment of PMN to fibrinogen, but induced substantial release of MPO. Taken together these results highlight scleraxis as a potential treatment protein for inflammatory conditions involving PMN.

Support or Funding Information

NIH 4R25HL092611‐09 and National Science foundation (RII), 3T34GM008663‐20S1
CD2AP facilitates HCV production by targeting NS5A to lipid droplets and regulating lipid droplet biogenesis
Authors: Li Chaoyang
Published: November 2023

Lipid droplets (LDs) play an important role in the life cycle of hepatitis C virus (HCV). In HCV infected cells, the surfaces of LDs are decorated with HCV non‐structure protein NS5A and structure protein, core. However, the targeting of these proteins to LDs and the biogenesis of LDs are complex and not completely understood. Here, we describe that CD2 associated protein (CD2AP), a scaffolding molecule that regulates the actin cytoskeleton, plays dual functions to affect HCV assembly. First, by interacting with HCV non‐structural protein NS5A, CD2AP transfers NS5A via an actin dependent manner to a cellular machinery which is then targeting to LDs via the microtubule dependent manner. The interaction between NS5A and CD2AP requires the SH3 domain of CD2AP and the domain I of NS5A. Second, CD2AP affects HCV assembly by modulating LDs biogenesis. Down regulation of CD2AP significantly reduces biogenesis of LDs, NS5A and core protein location on LDs, and thus virus assembly but not HCV genome replication, virus entry, and virus IRES dependent translation. We found that in hepatocytes CD2AP, cbl‐b E3 ligase and IRS1 form a protein complex and binding between CD2AP and cbl‐b enhances IRS1 ubiquitination. Knocking down CD2AP increases IRS1 total protein and phosphorylated IRS1 level, affects AMPK to HSL axis, and results in reduced LDs biogenesis. Thus, CD2AP affects HCV assembly via two distinct pathways. Because CD2AP regulates LD biogenesis, our results not only provide mechanisms to understand HCV assembly but also point out a potential approach to target insulin resistance.

Support or Funding Information

Ministry of Science and Technology of China, Grant #: 2013CB911102
The plasminogen activation system in inflammatory arthritis pathogenesis
Authors: Flick Matthew
Published: November 2023

Rheumatoid arthritis (RA) is a common and debilitating autoimmune disease characterized by chronic inflammation, synovial hyperplasia, edema, cartilage and bone erosion and loss of joint function. Increasing evidence suggests that the plasminogen activation (PA) system plays a fundamental role in the mechanisms mediating inflammatory joint disease pathogenesis. Our laboratory has evaluated both plasminogen activators and plasminogen itself to define the role of the PA system in inflammatory joint disease. First, we examined the influence of plasminogen deficiency on TNFα‐driven arthritis in Tg197 mice that spontaneously develop early‐onset joint disease that progresses to debilitating polyarthritis. Comparative clinical analyses of both the distal joints of the fore‐ and hind‐paws and proximal joints of the knees revealed that plasminogen deficiency resulted in significantly elevated arthritic disease in distal joints but decreased arthritic disease within larger proximal joints relative to control animals. Thus, plasminogen appears to be a key molecular determinant of inflammatory joint disease capable of simultaneously driving or ameliorating arthritis pathogenesis in distinct anatomic locations in the same subject. To rigorously define the contribution of the urokinase‐type plasminogen activator system to arthritis pathogenesis, previously generated genetic deficiencies in both uPA and uPA receptor (uPAR) were inbred for 7 generations (99% inbred) to the well‐characterized, collagen‐induced arthritis (CIA)‐susceptible strain, DBA/1J. Our results indicate a near complete amelioration of joint disease in uPA‐deficient mice that was also observed in uPAR‐deficient mice. Further, inflammatory joint disease in CIA‐challenged mice was dependent on the expression of uPAR by hematopoietic‐derived cells as determined by reciprocal bone marrow transplant studies. Thus, these findings suggest that cell‐surface associated uPA/uPAR‐mediated proteolysis and/or uPAR‐mediated signaling events from bone‐marrow derived cells are important in promoting inflammatory joint disease, and that disrupting this key proteolytic/signaling system may provide a novel therapeutic strategy to limit clinical arthritis.
Novel functions of fibrinogen in liver toxicity and repair
Authors: Luyendyk James
Published: November 2023

Acetaminophen (APAP) overdose is a leading cause of acute liver failure. Multiple changes are evident in the hemostatic system of APAP overdose patients and changes in some hemostatic tests are associated with a poor outcome. Experimental APAP‐induced liver injury in mice is associated with activation of the coagulation cascade and intrahepatic fibrin(ogen) deposition. The overall goal of this talk will be to summarize recent results from our studies seeking to define the precise role of fibrin(ogen) in APAP‐induced liver injury and repair. We were surprised to observe that the protection afforded by anticoagulants in APAP‐treated mice was transient, and prolonged anticoagulation increased peak liver injury alongside evidence of delayed repair. Linking this observation to fibrin(ogen), mice lacking fibrin(ogen) had delayed liver repair after APAP overdose. The mechanism whereby fibrin(ogen) stimulated liver repair was determined to involve fibrin(ogen) engagement of the leukocyte αMβ2 integrin and induction of macrophage matrix metalloproteinase activity. The results highlight a novel pathway of liver repair after APAP overdose and the talk will highlight proof‐of‐concept pharmacologic studies targeting of this pathway to improve liver repair after APAP overdose.
Reflecting on student‐led teaching experiences allows students to become metacognitively aware of their anatomy and physiology knowledge
Authors: Bruzzini Kristen Blake
Published: November 2023

For several years, Maryville University has offered a week‐long summer program for high school students entitled Body Basics: Exploring Anatomy. Recently, the instruction of this course was transferred to upper‐level undergraduate physical therapy (PT) students. The PT students previously had taken combined Anatomy and Physiology coursework, as well as a year‐long gross anatomy dissection course. This student‐faculty collaborative study investigated the impact of student‐centered learning on the physical therapy students (the ‘teachers’ of this course) and whether the experience may influence their ability to articulate knowledge of anatomy and physiology to individuals with little or no anatomical background. The PT students journaled about their teaching experiences and completed surveys about their teaching experience. An inductive (qualitative) analysis of the journals was performed to determine common ‘themes’ about the PT students' teaching experience and their prior perceptions about their effectiveness as instructors. This study presents the case that assuming a teaching role requires students to explain concepts in anatomy, physiology, and kinesiology to a “lay audience” helping them attain clinical skills in communicating difficult concepts to patients they will eventually encounter.
Integrated anatomy and physiology in a medical curriculum
Authors: Silverthorn Dee U.
Published: November 2023

Anatomy and physiology often are taught together as part of a systems‐based integrated medical curriculum but at Dell Medical School, newly opened at the University of Texas at Austin, we are following a model more often seen in undergraduate curricula: a combined anatomy and physiology course. After an introductory course in biochemistry, molecular biology, and genetics, Dell Med students take a 12‐week block titled “Structure and Function.” The block includes weekly 4‐hour laboratory sessions with four stations: two stations with prosected cadavers plus digital histology, one station with hands‐on physiology experiments, and an imaging station that combines radiological imaging, ultrasound, and a Sectra Visualization Table (tm). Students spend 3 hours a week working in small groups on clinical cases that have elements of both anatomy and physiology. These cases are presented in a custom‐designed teaching electronic health record. Another 9 hours a week are devoted to large group interactive sessions with minimal lecturing. Students are expected to learn the basics on their own before class so that interactive time is spent applying knowledge and practicing problem‐solving. Scheduled classes are restricted to 18–20 hours a week to allow students ample time to learn independently. This talk will occur near the end of our first year in the curriculum and will include assessment of what worked and what needs to be improved.
Intervertebral disc degeneration and low back pain: Pre‐clinical studies and clinical implications
Authors: Stone Laura S
Published: November 2023

Chronic back pain is a major health problem throughout the world, affecting 10–15% of the global population. Current diagnostic and therapeutic approaches to chronic back pain are limited by our narrow understanding of the underlying biological mechanisms. While intervertebral disc degeneration has been linked to chronic back pain in humans, the relationship between disc pathology and pain symptoms remains a subject of debate. We are using mouse models of intervertebral disc degeneration to study this complex problem. Recent pre‐clinical findings on the relationship between progressive disc degeneration, pathological disc biochemistry and innervation and the emergence of behavioural signs of low back pain and radicular leg pain will be discussed. The therapeutic benefits of pharmacological and non‐pharmacological interventions (e.g. physical activity, diet) on these parameters will be presented and potential mechanisms underlying the low back pain and the beneficial effects of physical activity will be proposed.

Support or Funding Information

Supported by the Canadian Institutes of Health Research
Patterning coronary artery development
Authors: Red‐Horse Kristy
Published: November 2023

An important goal of developmental biology is to understand how millions of cells unite to produce a complex organ. For this process to be successful, the cells must take on proper fates at the appropriate times, in the correct proportions, and organize themselves so that the organ functions effectively. We are using the cardiovascular system as a model to understand the rules of these developmental events. Our laboratory is specifically focused on how cardiovascular progenitor cells behave in three dimensions and at the single cell level with inputs from physical forces. This allows us to study coronary development at high resolution to gain new information on how the cardiovascular system is assembled during embryogenesis and how developmental programs are reignited during disease.

Support or Funding Information

This research is supported by NHLBI of the National Institutes of Health under award number R01 HL128503.
Gross Anatomical Brain Region Approximation (GABRA): a new landmark‐based approach for estimating brain regions in dinosaurs and other archosaurs
Authors: Morhardt Ashley Caroline , Ridgely Ryan , Witmer Lawrence M
Published: November 2023

Studying brain evolution in extinct taxa can be challenging due to a lack of close correspondence between the morphology of the endocranial cavity and that of the underlying brain. Cranial endocasts may be faithful brain proxies in certain groups (mammals, birds) due to relatively complete filling of the cavity with neural tissue in life. However, the brain does not fill the endocranial cavity in many adult non‐avian archosaurs, making their endocasts less reliable indicators of brain size and shape. As such, previous studies of relative brain size and evolution in archosaurs relied on untested assumptions about brain‐endocast fidelity. We propose a new approach known as Gross Anatomical Brain Region Approximation (GABRA), which involves importing a digital endocast, derived from CT scanning and 3D visualization software, into modeling software (Maya). In Maya, brain regions underlying the endocast are modeled as 3D polygons. Discernable osteological correlates for soft‐tissue structures (e.g., neurovascular canals, dural sinuses, fossae formed by the brain itself) present on the endocast serve as anatomical landmarks that inform the location and size of the modeled general brain regions (e.g., cerebral hemispheres, cerebellum, optic lobes, olfactory bulbs). Together, the anatomical landmarks form a set of explicit criteria used to assess endocasts and model brain regions. GABRA criteria and resulting brain models were validated in extant diapsids (lizards, snakes, alligators, birds) via literature review, gross dissection, CT scanning of iodine‐stained specimens, and MRI studies. Therefore, GABRA models produced for extinct archosaurs are credible. Credible GABRA models for extinct dinosaurs provided volumetric estimates for general brain regions, which, when summed, offer a whole‐brain estimate. Such data from several dinosaurs have permitted analyses using modern comparative methods of relative brain‐size evolution (e.g., encephalization quotient), with results indicating that brain sizes for many dinosaurs were previously underestimated. Additionally, analyses of GABRA data show a mix of concerted and mosaic patterns of brain evolution, wherein the pituitary and olfactory bulbs emerge as evolving independently from the rest of the brain. In sum, GABRA provides insight into how brains evolved across dinosaur lineages. Future studies will examine within‐lineage changes, offering greater insight into how and why dinosaur brains evolved.

Support or Funding Information

Funding for this project was provided by the follow sources: the National Science Foundation, Jurassic Foundation, Sigma Xi Grant‐in‐Aid of Research, Ohio Center for Ecology and Evolutionary Studies, Ohio University Student Enhancement Award, Ohio University Original Work Grant.
A new Paradigm for Catalysis of Nucleotidyltransfer Reactions
Authors: Yang Wei , Gao Yang , Samara Nadine , Wu Jinjun
Published: November 2023

Enzyme catalysis has been studied for over a century. How it actually occurs has not been visualized until recently. By combining in crystallo catalysis with X‐ray diffraction analysis of reaction intermediates, we have observed the processes of DNA synthesis and RNA at unprecendented atomic detail. Contrary to the canonical view that enzyme‐substrate complexes and transition states have identical atomic composition and catalysis occurs by a two‐metal‐ion mechanism, we have discovered that it is essential for a third divalent cation to be captured en route to product formation. Unlike the canonical two metal ions, which are coordinated by DNA polymerases and nucleases, this third metal ion is not coordinated by the enzyme at all. Its location between the a‐ and b‐phosphates of dNTP in the case of DNA synthesis suggests that the third metal ion may drive phosphoryltransfer from the leaving group opposite to the 3′‐OH nucleophile. Experimental data indicate that binding of the third metal ion may be the rate‐limiting step in DNA synthesis, and the free energy associated with metal‐ion binding can overcome the activation barrier to the DNA synthesis reaction.

Support or Funding Information

Intramural Research of NIDDK, National Institutes of Health

IATAP, National Institutes of Health
What lurks beneath (the membrane): a mechanistic exploration of rhomboid proteolysis
Authors: Urban Sinisa
Published: November 2023

At the turn of the millennium an extraordinary class of enzymes that cut proteins inside the cell membrane was discovered. Rhomboid proteases are the largest family of these ancient membrane‐immersed enzymes. Although deceptively simple, the act of hydrolyzing a single peptide bond inside the water‐excluding environment of the cell membrane has evolved to trigger cell signaling events during bacterial growth and animal embryogenesis, as well as mitochondrial quality control throughout the life of a cell. The membrane is a challenging environment for catalysis. We have been pioneering new quantitative methods to study rhomboid catalysis directly inside the membrane and combining them with modern X‐ray crystallography approaches. I will discuss an integrated but unexpected model for how rhomboid proteases function, and the promising new opportunities that it raises for combating devastating parasitic diseases that have plagued mankind for millennia, including malaria.

Support or Funding Information

This work was supported by NIH grants 2R01AI066025 and R01AI110925, the Howard Hughes Medical Institute, and the David & Lucile Packard Foundation.
Pre‐mRNA splicing, histone modification, and the coordinated control of gene expression
Authors: Johnson Tracy L. , Hossain Munshi Azad
Published: November 2023

The emergence of whole genome and whole transcriptome sequencing has highlighted the need to explore new models to explain complex patterns of gene expression. For example, there has been a deepened appreciation for the role of diverse RNAs and their highly regulated processing in key cellular functions. Every step in the life cycle of an RNA—from its synthesis and processing to its export and translation—is subject to regulation. Recent studies have revealed that an added layer of regulation comes from the coupling and coordination of these reactions. RNA splicing, for example, occurs co‐transcriptionally, raising important questions about the interplay between transcription, chromatin, and the spliceosome as the cell regulates gene expression to adapt to a variety of environmental conditions.

Despite its relatively streamlined genome, there are important examples of regulated splicing in Saccharomyces cerevisiae that provide mechanistic insights into the coordination of nuclear processes. We previously demonstrated that intron retention (a phenomenon that is common in higher eukaryotes) plays a crucial role in the yeast cell's ability to execute the proper gene expression program in response to nutrient deprivation (Hossain, M.A., Claggett, J. et al. Molecular Cell 2016). The glycolytic transcription factor Gcr1 (GlyColysis regulator 1) controls expression of over 75% of the genes in actively growing yeast, and GCR1 RNA contains a highly conserved intron, which allows the cell to generate multiple RNA isoforms whose levels and ratios change upon glucose depletion. One of these isoforms containing the retained intron is translated from a start site within the intron, raising important questions about regulation of GCR1 splicing, export of the intron‐containing GCR1 RNA, escape of the RNA from the cytoplasmic surveillance machinery, and the mechanism of its translation from different translation start sites. Additionally, synthesis of GCR1 is tightly regulated, including the regulated utilization of alternative transcription start sites that direct the synthesis of RNAs to make functional proteins. Hence, GCR1 regulation reveals intriguing RNA processing mechanisms. Here we show a role for chromatin modification in both the synthesis and processing of GCR1 RNA and define the features of GCR1 that influence its regulation. Based on these results, we have analyzed the yeast transcriptome under a variety of conditions to assess the pervasiveness of these mechanisms in yeast cells. These results reveal common themes that govern the coordinated regulation of gene expression processes.

Support or Funding Information

This work was funded by:

Howard Hughes Medical Institute Professors Program grant # 52008140

The National Science Foundation MCB‐1051921

NIH GM‐085474