bluuebunny/crossref_metadata_2025 huggingface dataset:
Bowel Morphologic evaluation in Experimental Administration of an Extract Ethanolic of Genipa Americana
Authors: DE SOUZA CAVALCANTI KAREN PENA , SOUZA IVONE ANTONIA , Caribe Rebeca Alves , Silva Elisangela Christianne Barbosa , Cabrita Antonio Silverio
Published: June 2021

Genipa americana L. (Rubiacea), native to northern South America, has a broad distribution in nearly all Brazilian territory, constituting a species with potential for commercial cultivation and use in agroforestry systems. The fruit serves as hair and skin dye, edible food and as folk medicine. This study propose to evaluate whether there are possible bowel lesions caused by ethanolic extract (EE) of fruit from G. americana. Twenty Wistar males rats 8 weeks of age were distributed randomly in 2 groups with 10 animals each. Group I constituted a control group with no manipulation. The group II was submitted to the administration of the 100mg/Kg of EE of G. americana, by gavage, five times at week, during 8 weeks. All the animals were sacrificed after twenty‐eight weeks. The bowel of control had no lesions. The incidence of AC observed in the group II was 1.67 Â± 2.5 (2.6%) in the rectum, 50.22 Â± 21.32 (78.34%) in the colon and 13.75 Â± 4.89 (19.06%) in the cecum. Therefore, there were no neoplasm lesions. In conclusion, the macroscopic evaluation of the bowel revealed aberrant crypts (AC) and there were no neoplasmic lesions in the groups treated with the HE of the G. americana.
A Novel Mechanism for Calcium Entry Into Blood Platelets
Authors: Murad John Paul , Ting Harold J , Khasawneh Fadi T
Published: June 2021

In spite of the fact that changes in the intracellular levels of calcium (e.g., calcium entry (CE)) is a central step in platelet activation, the underlying mechanism of this CE is still ill defined. Previous studies have demonstrated that of the transient receptor potential channel (TRPC) family, TRPC1 and, to a higher extent, TRPC6 are expressed in blood platelets, whereas TRPC4 is found in megakaryocytes (at the mRNA level). Furthermore, recent studies have shown that TRPC1 deficient platelets exhibited no defects in platelet function, and unaltered calcium homeostasis. Based on these considerations, we hypothesized that TRPC6 plays an essential role in receptor‐operated calcium entry and platelet function. Our preliminary studies reveal that platelets deficient in TRPC6 exhibited a defect in platelet aggregation mediated by the thromboxane receptor at low agonist (U46619) levels (i.e., low levels of receptor activation). Moreover, TRPC6 deficient mice also exhibited a significantly prolonged bleeding time, and were protected against thrombosis development, using a FeCl3 carotid‐artery injury model. Together, these findings are consistent with the role of TPRs in hemostasis and the genesis of thrombosis. In future studies, we will investigate the role of TRPC6 in separate platelet functional responses such as dense granule secretion and shape change, and its role in platelet activation via separate platelet G‐protein coupled receptors such as PAR4 and P2Y1. These studies may define a new therapeutic target for managing multiple thrombosis‐based disorders.
Cardiovascular Profile of Oligomycin, a Mitochondial Complex‐V inhibitor, in Anesthetized Dogs
Authors: Chui Ray , Derakhchan Kathy , Sutherland Weston , Vargas Hugo M
Published: June 2021

Oligomycin A (oligo) is an antibiotic that inhibits mitochondrial complex‐V, leading to impaired energy formation in cells. Cells that have high energy demands, such as cardiac myocytes, may be sensitive to mitochondrial toxins, like oligo. Our goal was to determine the effect of oligo on hemodynamics and heart rate in the anesthetized dog preparation. Oligo was infused at 0, 0.01, 0.1 and 1 mg/kg IV (30 min/dose) and caused a dose‐related tachycardia (39–176%) and hypotension (19–36%). An increase in cardiac contractility (18–39%) was secondary to the heart rate increase (Bowditch phenomena). ATP depletion can stimulate norepinephrine release from sympathetic neurons, therefore, a follow‐up study evaluated whether atenolol could block oligo‐induced tachycardia. Atenolol (5 mg/kg, IV) demonstrated that the tachycardia induced by 1 mg/kg oligo was sensitive to cardiac b1‐blockade, but negative inotropy was not observed. These findings show that acute administration of oligo in this model elicits a profound sympathomimetic response, including an increase in cardiac contractility. Since energy depletion would be expected to reduce cardiac contractility, it is plausible that an acute cardiac sympathomimetic response masks negative inotropy. Evaluation of oligo in isolated heart preparations, are needed to address whether complex‐V inhibition has a direct negative inotropic effect on cardiac myocytes.
Molecular analysis of translational regulation of thyroid hormone receptor alpha mRNA
Authors: Okada Morihiro , Nakajima Keisuke , Yaoita Yoshio
Published: June 2021

Amphibian metamorphosis proceeds under the control of thyroid hormone (TH) and thyroid hormone receptor (TR). TRs are encoded by two genes, TRα and TRβ. TRβ mRNA and protein rise along with the increase in endogenous TH. On the other hand TRα mRNA increases during metamorphosis, whereas TRα protein remains constant, suggesting that post‐transcriptional events control the levels of TRα protein. But the regulation of TRα protein expression remains largely unknown. We focused on the region of the TRα 5′UTR. At first, we determined nucleotide sequences of the TRα 5′UTR in amphibians by 5′‐RACE. There are highly conserved reigions in the TRα 5′UTR among the amphibians. We found that the TRα 5′UTR significantly repressed TRα mRNA translation as a cis‐regulatory element in Xenopus laevis A6 (XLA6) cells. Moreover, the TRα 5′UTR suppressed of a downstream open reading frame translation in both reticulocyte lysate and wheat germ extract. Successive deletions of the TRα 5′UTR revealed five elements to repress downstream translation. We analyzed two of five elements by extensive point mutations. One of elements is the GC‐rich region and the other is an upstream open reading frame (uORF). Most single base mutations in the GC‐rich region severely eliminated the repression of translation, while base substitutions didn't affect translational regulation by uORF.
A serum‐free chemically defined medium for the expansion of adult normal human dermal fibroblasts
Authors: D'Souza Theresa , Roderick Karen , Walde Amy , Bossie Alexis
Published: June 2021

Cultured dermal fibroblasts are used clinically for acute and chronic wound repair and as a source of collagen for cosmetic surgery. Typically cells are cultured in medium containing serum. The unknown components and variable nature of serum is a challenge in basic research and clinical applications. Alternatives to serum to supplement cell culture media is much sought after. We have developed a serum‐free chemically defined, fibroblast growth medium (TheraPEAKTM FGM‐CDTM), to propagate primary adult normal human dermal fibroblasts (NHDF). NHDFs from several donors grown in FGM‐CDTM, proliferated for multiple passages, maintained a fibroblast phenotype and expressed fibroblast‐specific markers comparable to serum‐containing control medium. NHDFs grown in FGM‐CDTM on several different plastic surfaces maintained equivalent monolayer growth, viability and fibroblast markers. The migration capacity of the fibroblasts in FGM‐CDTM was similar to migration in the control medium. Immunofluorescence staining showed that NHDFs synthesize more collagen I in FGM‐CDTM than in serum‐containing medium. Replacement of serum‐containing medium with TheraPEAKTM FGM‐CDTM for the in vitro expansion of fibroblasts provides a more defined environment for pharmacological manipulations for research studies and for clinical applications using fibroblasts. Source of research support: Lonza BioScience
Countering by methylxanthines of opioid‐evoked depression of spontaneous network oscillations in locus coeruleus of newborn rat brain slices
Authors: Panaitescu Bogdan , Ballanyi Klaus
Published: June 2021

Treatment of (preterm) infants with opioids for analgesia can inhibit medullary respiratory networks controling breathing. Countering such opioid‐evoked and spontaneous apneas of prematurity with theophylline or caffeine can elicit seizures. Here, we studied in 400 μm thick horizontal brain slices from 0–4 days‐old rats whether these methylxanthines also counter opioid depression and evoke hyperexcitability in neural networks of locus coeruleus. Suction electrode recording revealed synchronized regular neuronal population bursting in locus coeruleus at 0.5–5 Hz which was disrupted neither by 10 mM theophylline, 10 mM caffeine nor GABAA receptor blockade (bicuculline, 25 μM). At 25 nM, the μ‐opioid receptor agonist DAMGO transformed fast oscillations into slower group bursts whereas 100–250 nM DAMGO abolished rhythm. At 1 mM, theophylline in 250 nM DAMGO reactivated slow rhythm whereas 2.5–10 mM restored faster oscillations. Block of oscillations by 250 nM DAMGO led to concomitant 10–25 mV hyperpolarization and a fall of Fluo‐4‐AM imaged cytosolic Ca2+ baseline in locus coeruleus neurons which were (partially) reversed by 10 mM theophylline. Findings indicate that methylxanthines do not cause seizure in locus coeruleus but counter opioid‐evoked depression of these networks with involvement of postsynaptic mechanisms.
Lack of plasma albumin enhances glucose tolerance and insulin secretion
Authors: Figueira Tiago Rezende , Ribeiro Rosane A , Ignacio‐Souza Letícia M , Carneiro Everardo M , Vercesi Aníbal E , Oliveira Helena C
Published: June 2021

Congenital analbuminemic individuals and rats (NAR) present several metabolic abnormalities, such as hypertriglyceridemia and plasma free fatty acids (FFA) deficiency. We aimed at studying glucose homeostasis and insulin secretion in these dyslipidemic NAR. Measurements of plasma biochemical variables, insulin levels, isolated islet insulin secretion and glucose homeostasis tests were performed in female NAR and age‐matched controls (SDR, Sprague‐Dawley rats). Plasma glucose levels were similar in fed and fasted NAR and SDR. However, insulinemia was higher in fed NAR than in SDR (P ≤ 0.05). NAR showed increased glucose tolerance compared to SDR (P ≤ 0.05). This enhanced glucose tolerance was associated with higher insulinemia after the glucose load, and with similar insulin sensitivity between groups. Compared to SDR, isolated islets from NAR secreted more insulin in response to glucose and leucine. Despite similar liver glycogen content in fully fed condition, NAR had lower glycogen content (40% of control) after 6‐h fasting. The injection of pyruvate (gluconeogenic substrate) elicited a faster rise in glycemia in NAR than in SDR. In conclusion, NAR display enhanced glucose tolerance, insulin secretion, and gluconeogenesis rate. The higher glucose tolerance is attributed to enhanced islet responsiveness to secretagogues, while peripheral insulin sensitivity is not altered.
Elucidating the role of MC3R in melanocortinergic appetite regulation in chicks
Authors: French Casey , Kohart Nicole A. , Smtih Marissa L
Published: June 2021

The melanocortin receptors are implicated in both food intake and energy expenditure regulation but the role of the melanocortin 3 receptor (MC3R) is less understood than that of the melanocortin 4 receptor (MC4R). In both rodents and chicks, the proopiomelanocortin (POMC) derivatives α‐ and β‐melanocyte stimulating hormone (MSH) are thought to nonselectively bind MC3R and MC4R and decrease food intake. To investigate the role of MC3R in this response, γ2‐MSH, a POMC derivative agonist of MC3R, and Compound 7, a highly selective MC3R antagonist were centrally injected. γ2‐MSH decreased food intake through 180 min post injection while Compound 7 did not affect food intake until 90 min post injection. Interestingly, γ2‐MSH only decreased water intake up to 90 min post injection. γ2‐MSH also increased time spent sitting and decreased feed peck efficiency without affecting other ingestive or non‐ingestive behaviors. These data support a role for MC3R in appetite regulation in chicks, which is controversial in rodents.
Application of MIQE Guidelkines to Measuring Effects of Maternal Smoking on nAChR mRNA Expresiion in the Striatum
Authors: Williamson Paula Denise , Weiss Emily Sarah , Middleton Courtney , Adams Jamie , Dolan Maureen C , Buchanan Roger A
Published: June 2021

Prenatal exposure to the constituents of cigarette smoke (maternal smoking) is known to have deleterious effects on health. We report effects of maternal smoking on expression of nicotinic acetylcholine receptor (nAChR) subunits in the striatum. Pregnant dams were exposed to cigarette smoke (350 ml/exp, 3 exp/day) from gestational day 4 through parturition. Brain regions were harvested from male and female prepubertal (PND 20), pubertal (PND 35) and post‐pubertal (PND 60) pups of unexposed and exposed dams. RNA was extracted from tissue samples using a Promega Maxwell 16.. cDNA was reverse‐transcribed using iScript Select cDNA synthesis and amplified and detected with SSO Fast EvaGreen Supermix Green by real time RTqPCR.

cDNA was pooled and used to evaluate primer efficiencies, and reference gene stability. Primer efficiencies ranged from 72 to 117% and reference gene stabilities (M values) ranged from 0.2 to 0.8. mRNA expression of nAChR subunits α2, α3, α4, α5 a7, β2 and β4 was measured and compared at each PND, exposure and gender. Differences in expression of several subunits were observed. MIQE standards for reporting results of RT‐qPCR experiments were followed.

We also report results of mRNA extraction experiments performed on very small amounts of CNS tissue. These results show that sufficient amounts of mRNA can be obtained from samples as small as 1 mm3 and from identified brain regions from newborn (PND 1) pups.
A Hypertensive Drug Telmisartan Selectively Activates PPAR Anti‐Diabetic and Pro‐Adipocytic but not Anti‐Osteoblastic Activities in vitro and in vivo
Authors: Petluru Vipula , Lu Yalin , Rahman Sima , Lecka‐Czerrnik Beata
Published: June 2021

Anti‐diabetic drugs Thiazolidinediones (TZDs) improve insulin sensitivity by activating nuclear receptor PPARγ, however prolonged use causes bone loss and increases fracture risk. In marrow Mesenchymal stem cells (MSCs), activation of PPARγ2 with TZD rosiglitazone (R) induces adipocyte and suppresses osteoblast differentiation. The beneficial anti‐diabetic and pro‐adipocytic activities of PPARγ2 can be separated from the unwanted anti‐osteoblastic activity by using selective PPARγ agonists. The anti‐hypertensive drug Telmisartan (TEL) inhibits the activity of Angiotensin II receptor and also acts as a selective PPARγ agonist. Activation of PPARγ with TEL improves insulin resistance and lipid profile. We tested the effect of TEL on MSCs lineage commitment using U33/γ2 cell model of MSCs differentiation under the control of PPARγ2. TEL (50 μM) did not affect osteoblast phenotype, however it induced adipocyte phenotype. Next, we tested whether TEL may protect against the anti‐OB effect of R. U33/γ2 cells were treated with R alone (1μM) or in combination with TEL (50 μM). As expected, R alone suppressed osteoblast phenotype; however combined treatment with TEL and R did not affect ALP activity or expression of genes. Unlike R‐activated PPARγ2 which suppresses the activity of TGFβ/BMP signaling pathway, TEL did not affect pathway activity and protected from negative effects of R. When administered to hyperglycemic and diabetic Avy/a mice, both drugs had a similar antidiabetic effect. However, administration of R resulted in 60% decrease in trabecular bone mass, whereas TEL did not have any effect on bone. Moreover, when mice received combination of both drugs, TEL prevented bone loss induced by R. Thus, TEL selectively induces PPARγ2 anti‐diabetic activity without affecting osteoblastic phenotype in bone MSCs and in mice. Thus, TEL represents a paradigm of multifunctional drug, which can be used alone or in combination with R, for simultaneous treatment of hypertension and diabetes without adverse effects on bone.
Exercise Training Reduces Age‐Dependent Elevation of Angiotensin II Type 1 receptor and NAD(P)H Oxidase
Authors: Lee Yang , Hord Jeff M , Kwak Hyo‐Bum , Kim Jong‐hee , Lawler John M
Published: June 2021

Fibrosis in the aging heart impedes diastolic filling and increases arrhythmias. Previously, we demonstrated that exercise training (ET) reduced collagen I fibrosis and oxidative stress in the aging heart. Recent studies show that NAD(P)H oxidases (Nox) could be an important source of oxidative stress during the aging process, activated by renin‐angiotensin II‐aldosterone system (RAAS). Given that Nox and RAAS may elicit collagen accumulation in the aging heart, we tested the hypothesis that ET would alleviate age‐related upregulation of Nox (p47phox) and RASS (angotensin II receptor 1: ATR1) markers. Young (3 mo) and old (31 mo) FBNF1 rats were assigned into sedentary (YS, OS) and exercise (YE, OE) groups, with ET rats training on a treadmill 45 min/d, 5 d/wk for 12 wk. ET diminished web‐like geometry of connective tissue and large cardiomyocytes in the old age group. Aging increased p47phox–positive staining and protein expression 78.4% (p<.032) in the LV, while OE displayed lower p47phox‐positive staining, with protein abundance trending lower (−46.6%). gp91phox levels in OS trended higher 22.8% than YS. ATR1 was significantly elevated with age (+36.6%, p<.02), but was not significantly blunted with ET. Results indicate that exercise training may provide significant protection against Nox upregulation and thus fibrosis, while upstream regulation by ATR1 remains uncertain.
894G>T polymorphism of endothelial nitric oxide synthase impairs hemodynamic responses to mental stress
Authors: Rocha Natália Galito , Silva Bruno Moreira , Neves Fabricia Junqueira , Medeiros Renata Frauches , Carvalho Ana Cristina Gouvea , Sales Allan Robson Kluser , Toste Fabiane Pereira , Pereira Felipe Sá , Barbosa Thales Coelho , Nóbrega Antonio Claudio Lucas
Published: June 2021

Our aim was to evaluate the effect of the 894G>T polymorphism on the hemodynamic responses to mental stress performed before and after exercise. Subjects without (wild type, WT; n=16) or with (polymorphic type, PT; n=19) the polymorphism underwent a mental stress challenge before and after a bout of maximal dynamic exercise on a treadmill. Blood pressure and forearm blood flow were measured during mental stress. Before exercise, systolic blood pressure (SBP) response during mental stress was higher in the PT group (ΔWT: 8.0±2.0% vs. ΔPT: 12.5±1.8%, P=0.01), while the increase in forearm vascular conductance (FVC) was similar between the groups (ΔWT 90.8±26.4% vs. ΔPT: 86.3±24.1%, P=0.44). After exercise, the SBP at baseline and during mental stress was lower than before exercise in the whole group (P<0.05), but the pressure response during mental stress was still higher in the PT group (ΔWT: 5.8±1.5% vs. ΔPT: 10.2±1.4%, P=0.01). The increase in FVC was inhibited only in the PT group (Δbefore exercise 86.3±24.1% vs. Δafter exercise: 41.5±12.6%, P=0.04). In conclusion, subjects with the 894G>T polymorphism presented higher blood pressure response to mental stress, both before and after exercise along with blunted FVC increase after exercise. These results suggest that the 894G>T polymorphism is associated with altered hemodynamic responses to mental stress with potential clinical implications. Support: CNPq, FAPERJ, FINEP.
Moderate aerobic exercise reduces ozone‐produced oxidative stress in rats
Authors: VillanuevaLopez Guadalupe Cleva , MartinezCampos Catalina , Kross Robert David , LaraPadilla Eleazar
Published: June 2021

Nitric oxide (NO) increases as a result of exercise adaptation. Moderate exercise produces oxidative stress (OS) that stimulates endogenous antioxidant capacity. We previously found that ozone (O3) produced OS and endothelial dysfunction in rats. O3 has been related to increased all‐cause mortality in humans, and aerobic exercise reduced this relationship. The goal of this study was to determine if moderate aerobic exercise reduced OS produced by O3. Male Wistar rats (230–250 g, 10‐weeks old, n=12) were trained to swim 90 min daily (14 days). Six of the rats were exposed to O3 (0.5 ppm, 4 h/day) one hour before exercise. Two groups of sedentary rats (n=6, each) were used as control, one of which was exposed to O3. At the end of the experiment blood was taken from the carotid artery and the animals were euthanized. Measurements were made on the plasma. O3 decreased reduced nitrates (indirect measurement of NO) and produced OS manifested by increased plasma malondialdehyde and 8‐isoprostane, and decreased superoxide dismutase (SOD) activity. Exercise significantly blocked O3 effects, although SOD was also decreased by exercise (the greater drop was in the O3 group).

Conclusion

Aerobic exercise protects against OS produced by O3 and the effect is independent of SOD. Future studies will determine if exercise effects remain after long O3 exposure and if other antioxidants are responsible for those effects
Wingate Test Peak Power is Positively Correlated to Peak Torque and Power in Bilateral Isokinetic Knee Dynamometry
Authors: Lunn William , Zenoni Maria , Crandall Ian , Berglund Michelle , Dress Ashley , Wiley Charlie , Axtell Robert
Published: June 2021

The Wingate Anaerobic Test (WAnT) is a popular and common assessment of muscular anaerobic power and fatigability among power‐oriented athletes. Similarly, bilateral, isokinetic knee dynamometry (ID), assessing peak knee joint torque and power, has vital clinical applications for the rehabilitating power athlete.

Purpose

The aim of the study was to determine the relationship between peak power (PP_WAnT) and relative peak power (RelPP_WAnT) from the WAnT and knee joint peak torque (TORQ), relative peak torque (RelTORQ) and leg peak power (PP_ID) from ID in both flexion (FLX) and extension (EXT).

Methods

Healthy adult males (n = 14) completed a trial of each of the WAnT and ID test on separate days. Knee FLX and EXT were evaluated at three angular speeds (60, 180, and 300º/s). Flywheel resistance for the WAnT was individualized to elicit a peak pedaling cadence between 80–120 rpm during the test (7.0–11.0 % of body weight).

Results

Pearson product‐moment correlations were positive and strong for each leg at each speed in both FLX and EXT between PP_WAnT and each of TORQ and PP_ID, and between RelPP_WAnT and RelTORQ (p < 0.05).

Conclusion

Findings suggest that data from either the WAnT or the ID test may be used as a substitute for the other when assessing power outcomes in healthy adult males. This may be useful in laboratory or athletic training environments in which one, but not both, tests are available.
Aging Disrupts The Balance Between Positive And Negative Angiogenic Factors In Skeletal Muscle
Authors: Audet Gerald N , Nichols Cody E , Butcher Joshua T , Frisbee Jefferson C , Olfert I. Mark
Published: June 2021

Skeletal muscle microvessel density has been found to decrease with age in both rats and humans, but the mechanisms for this process are still poorly understood. Physiologic regulation of angiogenesis is thought to be controlled by a balance between positive and negative proteins, among which vascular endothelial growth factor (VEGF) and thrombospondin‐1 (TSP‐1) are emerging as two important factors. We hypothesized that age‐related reduction in skeletal muscle capillarity would correlate with lower VEGF and/or higher TSP‐1 levels. We measured protein expression of VEGF and TSP‐1 in the hind limb muscles, plantaris (PLT), soleus (SOL), and gastrocnemius (GA), of 12 week‐ (young, N=5–6) and 20 week‐ old (aged, N=3–6) lean Zucker rats. In the GA, aged animals had a 570% increase in TSP‐1 (p=0.014) and no difference in VEGF. In the PLT, aged animals had a no significant difference in TSP‐1 and a 60% decrease in VEGF (p=0.049). In the SOL, aged animals had a 198% increase in TSP‐1 (p=0.003), and no difference in VEGF. These results suggest that an altered balance between VEGF and TSP‐1 may be responsible for capillary rarefaction in aged muscle. Research supported by NIH 5T32‐HL090610 and AHA 10BGIA3630002.
Autophagy plays a beneficial role against mitochondrial dysfunction in cardiomyocytes
Authors: Dutta Debapriya , Xu Jinze , Wohlgemuth Stephanie , Dunn William A , Leeuwenburgh Christiaan
Published: June 2021

Healthy mitochondria are vital for cellular homeostasis and survival. Oxidatively stressed mitochondria can release pro‐apoptotic signals causing cell death. Dysfunctional mitochondria are removed by autophagy, a process during which damaged proteins and organelles are sequestered and degraded.

Objective

To determine whether interventions targeted to upregulate autophagy can protect HL‐1 cardiomyocytes against enhanced mitochondrial damage in HL‐1 cardiomyocytes.

Methods

HL‐1 cells were treated with the mitochondrial toxin Antimycin A (AMA), and mitochondrial superoxide generation, membrane potential, cellular DNA/RNA oxidation and cell viability were determined. Autophagy was stimulated using amino acid starvation or Rapamycin, and monitored with immunoblotting and epifluorescence imaging. Cell viability was tested with the MTT assay.

Results

AMA increased mitochondrial superoxide generation, decreased membrane potential, increased cellular DNA/RNA oxidation and decreased cell viability of HL‐1 cells. Both amino acid starvation and Rapamycin increased autophagy in HL‐1 cells, and attenuated AMA‐induced cell death.

Conclusion

Enhanced autophagy has a beneficial effect on survival of AMA‐treated HL‐1 cells. Research Support: NIH (R01 AG021042) to C. Leeuwenburgh and American Heart Fellowship to D. Dutta (10PRE4310091).
Influence of Nanoparticle Inhalation on Cardiac Mitochondrial Function
Authors: Croston Tara L , Baseler Walter A , Thapa Dharendra , Lewis Sara E , Nurkiewicz Timothy R , Yi Jinghai , Hollander John M
Published: June 2021

Particle inhalation affects directly contacted tissues. Nanoparticles may elicit more robust effects due to their greater surface area. However, the effects to extrapulmonary tissues, such as the heart, are unclear. Mitochondria play a critical role in cardiac function and may be negatively influenced by particulate exposure. Cardiac mitochondria are situated in a spatially distinct manner, with those between the myofibrils (IFM) and those beneath the sarcolemma (SSM). The goal of this study was to determine the effect of titanium dioxide (nano‐TiO2) inhalation on mitochondrial function. Sprague‐Dawley rats were exposed to nano‐TiO2 aerosols (CMAD=140–150 nm) at 4–5 mg/m3; for 4–6 hrs to achieve a pulmonary deposition of 30 ìg/rat. Twenty‐four hours later, echocardiography revealed a decrease in cardiac ejection fraction. Mitochondrial functional analyses indicated a decrease in electron transport chain complex III, IV, and V activities, with the IFM most affected (P<0.05, for all three). Lipid peroxidation and protein carbonyl contents were increased in exposed IFM, as compared to control. Caspase 3 and 9 activities were increased in exposed hearts with no effect on caspase 8 activity. The results suggest that nanoparticle inhalation is associated with cardiac mitochondrial damage which may be subject to subcellular spatial influence.

(Support: NIH DP2DK083095, 5T32HL090610, ES015022, ES018274)
Thermoregulatory responses are enhanced by glucose ingestion compared with fructose ingestion during passive heating in men
Authors: SUZUKI AKINA , OKAZAKI KAZUNOBU , IMAI DAIKI , TAKEDA RYOSUKE , NAGHAVI NOOSHIN , MATSUMURA SHINYA , KAWABATA TAKASHI , MIYAGAWA TOSHIAKI
Published: June 2021

Acute hyperglycemia attenuates the rise in esophageal temperatures (Tes) during exercise in the heat. We assessed the effects of acute hyperglycemia and insulin secretion on thermoregulatory responses.

Methods

Ten healthy young men performed two trials in a sitting position in an artificial climate chamber (28°C of Ta, 40% of RH). After 10 min baseline measurement, subjects drank glucose (GLU; water 300 ml + glucose 75 g) or fructose solution (FRU; water 300 ml + fructose 75 g), then 20 min after, they were heated passively (lower leg immersion in 42°C water) for 60 min. During experiment, plasma glucose concentration ([Glu]p), plasma osmolality (Posm), insulin and catecholamine concentrations, Tes and skin temperatures (Tsk), sweat rate (SR) and cutaneous vascular conductance (CVC) at forearm and chest were measured.

Results

[Glu]p was higher in GLU than FRU without significant differences in Posm and changes in plasma volume during passive heating. Tes threshold for sweating and cutaneous vasodilation at both sites were significantly lower in GLU than FRU. The sensitivity of increases in SR at chest at a given increase in Tes was significantly higher in GLU and FRU. Increase in Tes at the end of passive heating was lower in GLU than FRU.

Conclusion

Thermoregulatory responses during passive heating at rest were enhanced by glucose compared with fructose ingestion, which may be associated with insulin secretion.
Exercise modifies age‐related telomere dynamics in multiple tissues of CAST/Ei mice
Authors: Ludlow Andrew T , Witkowski Sarah , Marshall Mallory R. , Wang Jenny , Guth Lisa M. , Spangenburg Espen E. , Roth Stephen M.
Published: June 2021

Telomere length has recently been positively associated with physical activity and exercise training in white blood cells, but data in other tissues are limited. We sought to determine the effects of age and exercise on telomere dynamics in heart, liver and skeletal muscle in CAST/EiJ mice. Twenty‐seven CAST/EiJ mice were separated into three groups: baseline (BL; n = 6; 8 wk old), exercise (EX, n = 10), and sedentary (SED, n = 11). EX animals had prolonged access to a running wheel from 8 wks of age until 52 wks of age (6.2±2.3km/d). SED animals were housed individually without a running wheel until 52 wk old. Telomere length, telomerase enzyme activity, mRNA and protein levels of telomere‐associated genes were determined. In heart and liver, telomere length decreased with age (SED vs BL) while exercise attenuated the loss of telomere length (P≤0.01). In skeletal muscle, age had no effect on telomere length vs BL but EX significantly reduced telomere length. Telomerase enzyme activity was not different in SED or EX vs BL in heart or liver, but was elevated vs SED in EX skeletal muscle. In general mRNA levels of telomere binding proteins (Trf1/2, Pot1a/b) decreased in heart and skeletal muscle with age, and EX was able to significantly attenuate this reduction, particularly in the heart (P≤0.05); no changes were observed in the liver. We conclude that telomere dynamics in vivo respond to age and exercise in a tissue specific manner.

Support provided by NIH/NIA AG‐00268 and the Dept. of Kinesiology Graduate Student Research Initiative Fund.
Low Receptor Interacting Protein 140 (RIP140) Expression Adversely Impacts Proximal Insulin Signaling in L6 Skeletal Muscle Cells
Authors: Constantinescu Silvana , Turcotte Lorraine P
Published: June 2021

We have shown that reduced expression of receptor interacting protein 140 (RIP140) alters the regulation of muscle fatty acid (FA) uptake and FA oxidation under basal and insulin‐stimulated conditions. To provide mechanistic insights for these changes, we measured the gene expression and protein content of proteins known to be involved in metabolic regulation. L6 myotubes were silenced using RNAi sequences for either RIP140 (RIP) or a negative control (NC) and incubated ± insulin (I: 1000 nM). As expected, RIP140 protein content (53%) and gene expression (37%) were decreased (P<0.05) in RIP cells. Low RIP140 expression increased (P<0.05) nerve growth factor IB (Nur77) gene expression (92%) but did not affect medium chain acyl‐CoA dehydrogenase (MCAD) expression. In NC cells, insulin did not affect MCAD or Nur77 expression while it decreased (P<0.05) Nur77 expression in RIP cells. Insulin increased fibroblast growth factor 21(FGF21) protein content in NC cells, but it had no effect in RIP cells. Low RIP140 expression increased basal AKTSer473 phosphorylation and prevented the insulin‐induced increase in AKTSer473, AKTThr308 or PKC‐ξThr408/410 phosphorylation. We conclude that low RIP140 expression directly affects the expression of several proteins associated with metabolic regulation and adversely impacts the induction of proximal insulin signaling.

USC Women in Science and Engineering, USC Integrative and Evolutionary Biology and USC Zumberge Research Innovation Fund
Bortezomib partially protects the rat diaphragm from ventilator‐induced diaphragm dysfunction
Authors: Agten Anouk , Maes Karen , Thomas Debby , Decramer Marc , Gayan‐Ramirez Ghislaine
Published: June 2021

Controlled mechanical ventilation leads to diaphragmatic contractile dysfunction and atrophy. Since proteolysis is enhanced in the diaphragm during controlled mechanical ventilation, we examined whether the administration of a proteasome inhibitor, Bortezomib, would have a protective effect against ventilator‐induced diaphragm dysfunction.

Anesthetized rats were submitted for 24h to CMV while receiving 0.05mg/kg Bortezomib (MVB) or saline (CMV). Control rats were acutely anesthetized (C). After 24 hours, diaphragm forces were significantly decreased in the CMV group compared to C (−36%, p<0.001). Administration of Bortezomib improved the forces compared to CMV (+15%, p<0.01), but did not return to control levels. Compared to C, diaphragm cross sectional area (CSA) of the type IIx/b fibers was significantly decreased with 22% after CMV (p<0.05), while the CSA of the different fiber types in MVB remained similar to that of C. Diaphragmatic calpain activity was significantly increased (+63%, p<0.05) in CMV, but not in MVB. No differences were found in the activity of caspase‐3. These data show that the administration of Bortezomib partially protects the diaphragm from CMV‐induced diaphragm dysfunction.
The role of miRNAs in bladder contractility
Authors: Sadegh Mardjaneh Karbalaei , Ekman Mari , Rippe Catarina , Uvelius Bengt , Swärd Karl , Albinsson Sebastian
Published: June 2021

MicroRNAs (miRNAs) are small noncoding RNAs which modulate gene expression. Biogenesis of miRNAs depends on the activity of the endonucleases Dicer and Drosha. miRNAs are important for processes ranging from development to tumorigenesis. miRNAs also play an important role in vascular smooth muscle differentiation, in part through effects of miR‐145. The role of miRNAs in urinary bladder structure and function still remains unexplored, however. Here we investigated the role of miRNAs in the urinary bladder using conditional smooth muscle‐specific Dicer‐deficient mice. Ultrastructure was examined by electron microscopy (EM) and contractility by myography. Detrusor nerves were activated using electrical field stimulation. Differentiation was assessed by measuring the content of contractile proteins by immunoblotting. The Dicer KO detrusor displayed a substantial decrease in force in response to carbachol and high K+. Stress was however unchanged suggesting reduced bladder wall thickness. No reduction in the relative expression of contractile proteins could be observed. No conspicuous ultrastructural differences were observed by EM but cellular distances appeared increased. Smooth muscle miRNAs are thus essential for detrusor function independently of an effect on smooth muscle differentiation markers. Supported by Swedish Research Council, Faculty of Medicine at Lund University.
Maximal oxygen consumption, per exercise modality, in asthmatics with normal spirometry
Authors: Kist William B. , Sharp Joshua , Perez Kevin , Burgess Katy , Laws Ryan
Published: June 2021

Asthma is characterized by intermittent airway obstruction with chronic inflammatory processes leading to airway remodeling. The objective was to determine if maximal oxygen consumption (VO2max), per exercise modality, was altered by airway remodeling. Fourteen participants (N = 14), eight “Normals” (N = 8, age = 22 ± 3 y, body fat = 12.2 ± 3.7%) and six “Asthmatics” (N = 6, age = 23 ± 5 y, body fat = 19.6 ± 4.0%) underwent three VO2max trials, one via treadmill (TM), a second, seated on a cycle ergometer (CE, Sit‐CE), and a third, standing on a CE (Stand‐CE). ANOVA (group by trial) demonstrated significant (p = 0.05) differences by group on VO2max (Normals TM = 46.2 ± 10.5 ml.kg−1.min−1, Sit‐CE = 38.5 ± 8.5, Stand‐CE 41.6 ± 10.0; Asthmatics TM = 32.5 ± 8.0, Sit‐CE = 23.4 ± 8.6, Stand‐CE = 26.3 ± 8.6), VO2max‐minute ventilation (Normals TM = 115.6 ± 27 L.min−1, Sit‐CE = 105.4 ± 30, Stand‐CE = 107.2 ± 30; Asthmatics TM = 88.5 ± 13, Sit‐CE = 65.4 ± 12, Stand‐CE = 87.1 ± 32), but not VO2max‐heart rate (Normals TM = 184 ± 10 b.min−1, Sit‐CE = 169 ± 11, Stand‐CE = 174 ± 10; Asthmatics TM = 185 ± 8, Sit‐CE = 163 ± 14, Stand‐CE = 180 ± 14). Spirometry was normal pre/post trials. In conclusion, Asthmatics low VO2max, most prominent during CE, was not due to airway remodeling, but rather, likely caused by exercise avoidance per fear of airway obstruction. This study was funded by an internal grant from the University.
Proteomic analysis of differentially expressed proteins in human hepatocellular carcinoma cells after 4‐O‐carboxymethyl ascochlorin treatment
Authors: Kang Jeong Han , Maurizi Michael R.
Published: June 2021

The synthetic derivative of ascochlorin, 4‐O‐carboxymethyl ascochlorin (AS‐6), ameliorates type II diabetes in mice and also activates PPAR‐γ. We performed a proteomic analysis of human hepatocellular carcinoma HepG2 cells exposed to AS‐6 to identify proteins that accumulated to in higher or lower amounts. We found 58 differentially expressed proteins representing 55 unique protein species. AS‐6 treatment led to up‐regulation of ER stress‐related proteins including glucose‐regulated protein 78 (BiP/GRP78) and protein disulfide isomerase (PDI). The observed changes in expression of GRP78, PDI, and a select group of other proteins were validated by real‐time PCR, Western blotting, and immunostaining. We propose that AS‐6 exerts its cytotoxic effect via a mechanism initiated by ER stress followed by autophagy. Because it activates autophagic pathways, AS‐6 has potential as a drug lead for anticancer agents with therapeutic utility.
Changes in tyrosine‐nitrated proteins in the hippocampus of adult‐and middle‐aged rat
Authors: Uda Munehiro , Kawasaki Hiroaki , Shigenaga Ayako , Yamakura Fumiyuki
Published: June 2021

Nitration of tyrosine residues in proteins is widely used as a marker for oxidative or nitrative stress in animal cells. Increase in tyrosine‐nitrated proteins with age in rat hippocampus and identification of several tyrosine‐nitrated proteins from aged rat muscles have been reported. However, no study on the protein nitration in the brain of adult‐ and middle‐aged rats has been demonstrated yet. In this study, we determined relative contents of nitrated proteins, nitric oxide synthases (NOS), and superoxide dismutases (SOD) in the hippocampus of adult‐ and middle‐aged F344 rats. We also determined difference in nitrated proteins between the adult‐ and middle‐aged rat hippocampus by using two‐dimensional electrophoresis (2DE). Western blot analyses showed that relative contents of nitrotyrosine‐containing proteins and expression of Mn‐SOD, EC‐SOD, nNOS, and eNOS were not different between the adult‐ and middle‐aged rats. However, the expression of Cu, Zn‐SOD was increased in the middle‐aged rat compared with that of adult rat. Furthermore, several spots for tyrosine‐nitrated protein in 2DE were different between the adult‐ and middle‐aged rats. Thus, although the nitrative and oxidative stress may not different so much between the adult‐ and middle‐aged rat hippocampus, target proteins for the nitration are changed. Proteome analysis of the nitrated proteins is underway in our laboratory.
Relative location of transmembrane regions of GABAA receptors probed by cysteine substitution and crosslinking
Authors: Hicks Jessica Anne , Borghese Cecilia M , Harris R. Adron , Trudell James R.
Published: June 2021

The GABAA receptor is a likely target for alcohols and volatile anesthetics. The transmembrane regions (TMs) 1, 2 and 3 provide one amino acid each that line a putative alcohol and volatile anesthetic binding site. However, the relative position of these amino acids is still uncertain, as the pocket they line could be located between or within receptor subunits. Introducing cysteines in key TM locations, we tested the proximity of cysteine pairs by applying reducing and oxidizing agents that may break or form disulfide bridges between cysteines that are close enough, usually altering GABA‐induced currents through the receptor. Wild‐type and cysteine mutant α1 and β2 GABAA receptor subunits were expressed along with wild‐type γ2 in Xenopus laevis oocytes. A cysteine located in either α1 TM1 or β2 TM2 was paired with a cysteine in different positions along β2 TM3. EC50 GABA‐induced currents were recorded before and after application of dithiothreitol or copper:phenanthroline. Three pairs of cysteines appeared to crosslink. We will test alcohol and volatile anesthetics in GABAA receptors containing these cysteine combinations, before and after application of reducing or oxidizing agents. We expect that, if the cysteines that crosslink are located in the drug binding site, the drug's effect will be decreased. The results will be used to inform structural models based on recent high‐resolution structures of related channels.
Classification of the Items (Ingredients) in a 40‐day Rotating Menu Offered to Day‐Care Center Attendees in a Government‐Sponsored Program (SOSEP) according to the Monteiro Scale of Food‐Processing
Authors: Soto-Méndez María-José , Hernández Liza , Solomons Noel W.
Published: June 2021

Background

It has been suggested that the advance of processing of the foods in the human diets is causally associated with increasing chronic disease risk.

Objective

To classify the ingredients in the menu served to Guatemalan preschoolers in a day‐care center system according to the Monteiro Scale of food‐processing, modified for ingredient scoring.

Methods

The menu of the SOSEP, a Guatemalan government‐subsidized community day‐care system for low‐income preschoolers prescribes breakfast, lunch and 2 snacks daily, over 5‐d weekly, within a 8‐wk (40‐d) rotation. Dishes and recipes were reduced to their ingredients. Following the Monteiro Scale (Monteiro et al, Cad. Saúde Pública 2010), we classified each ingredient item as: GI, unprocessed/minimally processed; GII, processed; or GIII, ultraprocessed, and tabulated by menu appearance, and energy and weight contributions. Any item with added fortificant nutrients is classified as a GIII item.

Results

We identified 102 ingredients in the menu. 60 (59%) were GI, 12 (12%) GII, and 30 (29%) GIII. The percentage of energy provided by the respective classes was: GI 24%; GII 31% and GIII 45%. In terms of the proportion of the weight of menu offering, the respective contributions were: GI 66%; GII 11%; and GIII 23%.

Conclusion

Menus still conserve a predominance of unprocessed items. Association of energy density with ultra‐processing clearly stands out.
Long‐term physical illness in anorexia nervosa and bulimia nervosa
Authors: Gerhardt Ann
Published: June 2021

We sought to determine the types of long term, non‐psychiatric illness that occur in women currently practicing or with a history of anorexia nervosa and bulimia nervosa. From a 20‐year, internal medicine practice specializing in nutrition and eating disorders, we attempted to locate 488 eating disorder patients who had achieved age 30 years at the time of the study. Seventy‐nine women were found and 73 agreed to participate by completing a questionnaire, which asked 9 questions concerning current and past disordered weight control behavior, 30 questions about symptoms, medical conditions and presumptive diagnoses, and single questions about family medical history and medications. 44% were no longer practicing disordered eating. Prevalence of symptoms or diseases of the following systems: 60.3% musculoskeletal, 50.7% gastrointestinal (8.2% hepatic), 41.1% cardiovascular, including 22.5% with mitral valve prolapse, 34.2% respiratory, 27.4% hematologic, 26% reproductive, 17.8% dermatologic, 15.1% endocrine, 8.2% renal and 4.1% neurologic. Only 7 (9.6%) had no physical illness. There was no association of eating disorder diagnosis with frequency of physical illness.

Conclusion

Long term physical symptoms and illness are common in eating disorder patients, even after eating disorder recovery. Support from Sutter Community Hospitals Institute for Medical Research
Association of adverse antenatal and perinatal events with occurrence of Autism: A Case Control Study
Authors: Al-Farsi Yahya M , Al-Khaduri Maha M , Al-Sharbati Marwan M , Waly Mostafa I , Al-Farsi Omar A , Al-Shafaee Mohammed A , Deth Richard C
Published: June 2021

Background

Early life events, especially during perinatal and neonatal period, have been proposed as important factors in the etiologic pathways of autism.

Objectives

To evaluate the association between selected antental and perinatal adverse events and autism spectrum disorders (ASD).

Methods

A retrospective case‐control study has been nested on ongoing prospective cohort study, and it included 102 ASD cases and 102 controls.

Results

Adjusted odds ratios (OR) were generated from logistic regression models. ASD was found to be associated with social problems during pregnancy (OR = 1.39; 95% CI 1.01, 4.2), serious illness or trauma (OR = 1.5; 95% CI 1.02, 3.2), medication intake during pregnancy (OR = 1.6; 95% CI 0.96, 4.6), and premature delivery (OR = 1.7; 95% CI 1.1, 2.6). No evidence has been obtained for a significant association with gestational diabetes, anemia, and exposure to X‐ray, or caesarian section.

Conclusions

This study indicates that adverse early life events mightbe associated with increased risk of ASD. Further proof is sought through conduct of an undergoing prospective cohort study.
Relationship of parental dyad feeding styles on children's weight status and related obesogenic behaviors
Authors: Mobley Amy R. , Vollmer Rachel L. , Sigman-Grant Madeleine
Published: June 2021

Previous research regarding parental feeding styles and child weight has focused on mothers. The objective of this study was to examine the relationships of feeding (Caregiver Feeding Style Questionnaire) styles between mother/fathers on weight status and associated behaviors (Healthy Children, Healthy Families checklist) of their youngest child between the ages 3–10 years old. Triads (n=30) consisting of low‐income mothers, fathers and children were recruited. Each parent was interviewed individually and each family member was weighed and measured. BMI z‐scores were determined for children. While half of the parent dyads had the same feeding style, paired feeding styles were not significantly correlated (r=.309, p=.10). High responsiveness feeding style scores between parental dyads were correlated with lower BMI z‐scores (r=‐.352, p=.05) and less frequent soda consumption (rs=‐.542, p=.002) while high demandingness parental dyad scores were correlated with more frequent soda consumption (rs=.510, p=.004) in children. Research should continue to investigate the interaction of parental feeding styles on child weight and associated behaviors for future interventions.