bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibitory effect of Canavalia gladiata extract on gastric inflammation induced by acute ethanol treatment in SD rats
Authors: Kim Ok kyung , Ho Jin‐Nyoung , Nam Da‐Eun , Lee Jeongmin
Published: June 2021

We investigated the inhibitory effect of Canavalia gladiata water extract (CGW) on ethanol‐induced gastric inflammation, specifically on gastric acid secretion and gastric mucosal damage in Sprague‐Dawley (SD) rats. The possible mechanisms of CGW actions via ROS was also further determined for antioxidant effects. Rats were divided into four groups : saline(G1), gastric inflammation plus saline(G2), gastric inflammation plus Lansoprazole 30mg/kg b.w(G3), gastric inflammation plus CGW 250mg/kg b.w(G4), gastric inflammation plus CGW 500mg/kg b.w(G5). After oral administration of either saline, Lansoprazole or CGW for 7 days, acute gastric inflammation was induced by oral administration of 1mL of 70% ethanol and 0.15M HCl at groups G2,G3,G4 and G5. After 1h on ethanol administration, all animals were sacrificed. Gastric acid secretion and gastric mucosal injury were significantly decreased in G3 when compared to that of G2. And groups pretreated with CGW (G4, G5) caused a significant decrease in gastric acid secretion and gastric mucosal injury in a dose dependant manner. To examine the regulatory factors related inflammation, NF‐kB, COX‐1, COX‐2 and cytokines were measured by immuno‐histochemistry and ELISA. The expression of NF‐kB, COX‐1 and COX‐2 were clearly decreased in G3 and G5 compared with the G2. Additionally, cytokines was significantly decreased in G3 and G5. We next examined the levels of MDA and SOD activity related in antioxidative effects. Oral administration of CGW significantly decreased levels of MDA and SOD activity was dramatically increased. In conclusion, our data show that CGW has inhibitory effects on gastric inflammation induced by acute ethanol treatment in SD rat. Although the exact mechanism underlying these actions is unclear, the effects on acute gastric lesions suggest a multifactorial mechanism probably involving the antioxidant properties of CGW.
A genome‐wide association study (GWAS) of the human plasma proteome
Authors: Jamnik Joseph , Garcia‐Bailo Bibiana , Borchers Christoph , El‐Sohemy Ahmed
Published: June 2021

High‐abundance plasma proteins are involved in disease‐associated pathways and are useful biomarkers of disease states and dietary exposures. The concentrations of these proteins vary across individuals, but it is unclear whether the observed differences are related to inter‐individual genetic variation. The objective was to explore associations between genome‐wide genetic variants and 54 plasma proteins belonging to disease‐associated pathways in healthy young adults (n=488) from the Toronto Nutrigenomics and Health Study. We report the first GWAS to be conducted on the human plasma proteome. Protein concentrations were measured by a multiple reaction monitoring HPLC‐MS/MS assay. Linear regressions with an additive mode of inheritance were used to explore the associations between genetic variants and plasma proteins. We identified 40 variants in 12 genes that were significantly (p< 1.13×10−9) associated with the proteins analyzed. Variants in genes that encode α1B‐glycoprotein, gelsolin isoform 1, histidine‐rich glycoprotein, and α2‐HS‐glycoprotein were each associated with circulating levels of their respective protein. These results suggest that common genetic variants modify circulating levels of plasma proteins involved in actin scavenging, inflammation, and other immune responses. Research support from the Advanced Foods and Materials Network.
Obesogenic phenotype of offspring of dams fed a high multivitamin diet is prevented by a post‐weaning high multivitamin or high folate diet
Authors: Cho Clara E. , Sanchez‐Hernandez Diana , Reza‐ Lopez Sandra A. , Huot Pedro S.P. , Kim Young‐In , Anderson G. Harvey
Published: June 2021

High multivitamin (10‐fold, HV) diet fed during pregnancy to Wistar rat dams increases food intake and characteristics of metabolic syndrome in their offspring weaned to the recommended vitamin (RV) AIN‐93G diet. This study determined if a HV or 10‐ fold high folate (HFol) diet fed to the offspring prevents the consequences of the HV gestational diet through epigenetic effects on hypothalamic mechanisms regulating food intake. Male offspring of dams fed the HV diet were weaned to RV, HV or HFol diets for 29 weeks, compared to those born to RV dams and weaned to the RV diet. Food intake, body weight, glucose response to a glucose load, hypothalamic gene expression and global DNA methylation were measured. Both the HV and HFol pup diets prevented the increase in food intake (5%, P=0.03), body weight (8%, P=0.0006) and glucose response (36%, P=0.02) found in offspring of HV dams weaned to the RV diet. Expression of proopiomelanocortin (160%, P=0.004) and brain‐derived neurotrophic factor (BDNF) (170%, P=0.02) was higher in pups fed the HV diet. The HFol pup diet also increased BDNF (130%, P=0.02), and lowered serotonin receptor 2A (60%, P=0.008) expression. Global DNA methylation was similar among groups. In conclusion, increasing the vitamin or folate content of the pup diet is effective in preventing the obesogenic phenotype in offspring of HV dams possibly due to post‐weaning modulation of food intake regulatory mechanisms.

Grant Funding Source: Canadian Institutes of Health Research, Institute of Nutrition, Metabolism and Diabetes
Search for plasma biomarkers for dilated cardiomyopathy using a mouse model with sialyltransferase transgenes
Authors: Suzuki Osamu
Published: June 2021

I reported that a strain (4C30 strain) of mice with sialyltransferase (ST3GalII) transgenes would be a new mouse model for adult‐onset dilated cardiomyopathy (Proc Jpn Acad Ser B Phys Biol Sci. 2011; 87(8):550–562). To find plasma biomarkers for dilated cardiomyopathy, I compared plasma proteins in our cardiomyopathic 4C30 mice with those in a normal control strain (C57BL/6NCr). Plasma samples were collected from 15‐wee‐old males of both 4C30 and control strains. The plasma samples were treated with ProteoMiner columns (PMC, Bio‐Rad) and applied to 2‐dimension electrophoresis (Isoelectrofocusing ranging pH 5–8 and SDS‐PAGE using 4–12% gels) with SyproRuby staining. Enolase‐β (Eno3) was identified by mass spectrometry as a preferentially expressed protein in 4C30 plasma. Western blots and SyproRuby‐stained gels confirmed that Eno3 per total protein was significantly more abundant in PMC‐treated plasma samples from 4C30 than in those from control (n=6; p=0.016 by ANOVA). These results suggest that the Eno3 would be a possible plasma biomarker for monitoring cardiomyopathy. This work was supported by a grant from the Ministry of Health, Labor, and Welfare of Japan.
Adiponectin inhibits leptin‐induced cardiomyocyte hypertrophy by attenuation of calcineurin/NFAT activation
Authors: Rajapurohitam Venkatesh , Suen Brandon , Karmazyn Morris
Published: June 2021

Leptin and adiponectin are adipokines which exert opposite effects on cardiac pathology. Leptin induces cardiomyocyte hypertrophy and hyperleptinemia has been shown to be a risk factor for developing heart failure. In contrast adiponectin is antihypertrophic and reduced plasma adiponectin levels constitute a cardiovascular risk factor. In the present study we determined whether adiponectin can modify leptin‐induced hypertrophy in cultured rat ventricular myocytes. Leptin (3.1 nM) treatment for 24 h produced a robust hypertrophy as evidenced by significantly increased cell surface area, α‐skeletal actin gene expression and rate of protein synthesis. These effects were associated with significantly increased calcineurin activity and import of the transcriptional factor NFAT3 into nuclei. The leptin–induced calcineurin activation was paralleled by increased intracellular Na+ and Ca2+ concentrations. The pro‐hypertrophic effect of leptin was completely prevented in myocytes co‐treated with adiponectin (0.5 μM). These effects were associated with attenuation of leptin‐induced elevations in intracellular Na+ and Ca2+ concentrations, calcineurin activation and NFAT3 nuclear translocation. Thus, adiponectin may represent an endogenous factor mitigating the pro‐hypertrophic effect of leptin by preventing calcineurin activation. Supported by the Canadian Institutes of Health Research.
Autophagy in neuronal bioenergetics and survival
Authors: Zhang Jianhua , Dodson Matthew , Liang Qiuli , Benavides Gloria , Darley‐Usmar Victor M
Published: June 2021

Neurodegeneration are associated with multiple hits at metabolic pathways including those involved in metabolism (mitochondria and glycolysis) cell signaling (Keap1‐Nrf2 or apoptosis) or cell repair pathways (fission/fusion and autophagy). We investigated the regulation of autophagy in neuronal response to oxidative and nitrative stress. 4‐hydroxynonenal (HNE) is a lipid peroxidation product formed during oxidative stress, accumulated in neurodegenerative diseases, and can further induce formation of other reactive species. DETA‐NONOate is a nitric oxide donor, used to mimick excessive nitric oxide produced by both neurons and glia in neurodegeneration. We found that HNE and DETA‐NONOate decrease mitochondrial oxygen consumption. Interestingly, HNE inhibited, and DETA‐NONOate stimulated glycolysis. The glycolysis response was inversely correlated with autophagy, as HNE stimulated and DETA‐NONOate inhibited autophagy. To investigate how glucose metabolism and autophagy play a role in mitochondrial quality control and cell death, we blocked glycolysis using 2‐DG, and found that 2‐DG abolished glycolysis, decreased mitochondrial reserve capacity, inhibited autophagy and exacerbated HNE‐ and DETA‐NONOate‐induced cell death. Inhibition of autophagy by 3‐MA, while increased glycolysis which is in contrary to 2‐DG, decreased mitochondrial reserve capacity and exacerbated HNE‐ and DETA‐NONOate‐induced cell death, effects similar to 2‐DG. Moreover, we found that 2‐DG played an important role in regulation of Bcl‐2 expression and 3‐MA played an important role in regulation of Drp1 and JNK activity. Our studies provide novel insights into how regulation of autophagy and glucose metabolism plays an important role in neuronal bioenergetics and survival in response to oxidative and nitrative stress. Funded by NIH and VA.
Scanning acoustic microscopy for characterization of gastric lesions
Authors: Miura Katsutoshi , Yamamoto Seiji
Published: June 2021

Study objective

A scanning acoustic microscope (SAM) is a device that uses ultrasound (frequency, 120 MHz) to image an object. Because the harder the tissue, the more the speed of ultrasound, SAM can provide data on the elasticity of tissues and lesions. Can SAM discriminate normal and pathological lesions of stomach?

Materials and Methods

Formalin‐fixed paraffin‐embedded sections of gastric lesions 10 um in thickness were used. We compared gastric lesions between SAM and light microscope (LM) images.

Results

SAM system discriminated gastric components and demonstrated distinct acoustic images such as adenocarcinomas, carcinoids, lymphomas leiomyomas(Figure) and GIST. Areas with thick fibrous portion and desmoplastic reactions associated with cancer invasion showed the greater speed‐of‐sound (SOS). Cell density portions also demonstrated the faster SOS than sparse area.

SAM provided the following benefits over LM: (1) images were acquired in only a few minutes without special stainings, (2) analysis by SAM system could be helpful to understand ultrasonic endoscopic images, and (3) digitized SOS data could be statistically compared among different lesions of stomach.

This work was supported by Japan Society for the Promotion of Science KAKENHI Grant Number 24590445.
Targeting retinoblastoma: therapeutic inhibition using catalytic antioxidant cerium oxide nanoparticles
Authors: Klump Kathryn Ellen , Cai Xue , Towner Rheal , Seal Sudipta , Dyer Michael , McGinnis James
Published: June 2021

Retinoblastoma is a malignant ocular tumor arising within the neural tissue lining the back of the eye during development. An excessive rise in reactive oxygen species (ROS) is associated with signaling cascades and mutagenic events during tumor initiation and angiogenesis in retinoblastoma. Cerium oxide nanoparticles (nanoceria) mimic the action of super oxide dismutase (SOD1) and catalase to destroy ROS. Our published data indicate that nanoceria are capable of reducing pathologic neovascularization in the mouse retina. We hypothesize that in vivo treatment with catalytic antioxidant nanoparticles will result in downregulation of VEGF, inihibition of angiogenesis, and decreased tumor growth in a mouse model of heritable retinoblastoma (P53TKO mice, Chx10‐cre; Rb Lox/−; p53 Lox/−; P107−/−). Mice in these experiments received a single intravitreal injection of nanoceria (172 ng/eye) at the onset of tumorigenesis. Tumor size and vascularity were monitored using fundoscopy, magnetic resonance imaging (MRI), and angiography. Western blot, RT‐PCR array and immunohistochemistry were used to evaluate changes in tumor associated gene and protein expression. Nanoceria resulted in a greater than 50% reduction in tumor burden 3 weeks post‐injection. These data indicate that nanoceria are potent inhibitors of tumor growth and may represent a novel therapeutic approach to targeting ocular malignancy.
Develop a novel aptamer‐mediated assay for simultaneous detection of different types of circulating tumor cells in whole blood samples
Authors: Zeng Zihua , Parekh Parag , Zhao Nianxi , Zu Youli
Published: June 2021

Oligonucleotide aptamers are a new class of small molecular probes. In contract to protein antibodies, aptamers can be chemically synthesized and easily modified with a variety of functional molecules. By conjugation of both fluorophore and quencher molecule we have previously developed a unique tumor cell‐activated aptamer reporter which is optically silent in the absence of cells of interest. However, the aptamer reporter can selectively target and highlight circulating tumor cells in whole blood with intracellular fluorescent signal. For simultaneous detection of different tumor cells, a new assay system containing aptamer reporters specific for multiple biomarkers (EpCAM, VEGF, and CD30) were formulated. Mixed tumor cells were added into the assay in a 96‐well microplate. After incubation for 30 minutes, the breast cancer cells, prostate cancer cells, and lymphoma cells were highlighted with different fluorescent signals, and simultaneously detected by fluorescent microscope without interference to each other. In addition, the new assay system was also validated in whole blood sample containing diluting cancer cells. Our study shows the first demonstration of a novel aptamer‐mediated assay, which is able to simultaneously detect different types of circulating tumor cells in a single assay with whole blood samples within minutes.
The newer therapeutic alternatives to the acid‐oriented approach via targeting endothelial metabolism in esophagoprotection by 5‐hydroxytryptamine (5‐HP) and melatonin (MT)
Authors: Zayachkivska Oksana , Savytska Maryana , Mandrusyak Solomiya , Yaschenko Antonina
Published: June 2021

Existing treatment of erosive and nonerosive esophagitis (NEE) which incidence has risen dramatically in recent years are mostly based on potent acid suppression. Modern data revealed that the prolonged acid suppression is associated with dismotility in foregut, extraesophageal disorders, abnormal microbiota, and induction selective apoptosis for cancer. We hypothesized that endothelial metabolism is key in multifactorial esophageal mucosa (EM) defense and studied 5‐HT/MT specific effects on EM endothelial metabolism during NEE associated to stress model (WRS) and 28 days of postprandial hyperglycemia (PPH) in rats was studied without/with 5‐HT (100 mg/kg) and MT (20 mg/kg) via VEGF, EGF, IL‐1β, TNFα synthesis by ELISA; EM injury via histological score index (HSI); functional reorganization of microangioarchitecture by mannose specific labeling.

Results

NNE constantly increased HSI in 150% in binary PPH and WRS; 5‐HT/MT decreased HIS 38% & 57%, respectively; potent MT and 5‐HT modulation vascular tone were through VEGF, TNFα synthesis better then 5‐HT. Changes in alfa‐DMan>;D‐Gal EM expression confirmed key role of endothelial metabolism in NEE and MT decreased expression of endothelial dysfunction. We concluded that MT has potent esophagoprotective effect then 5‐HT via decreasing endothelial permeability, thus may be alternative to the acid‐orientated approach.
Transcriptional suppression, DNA methylation, and histone deacetylation of the Regulator of G‐protein Signaling 10 (RGS10) gene in ovarian cancer cells
Authors: Ali Mourad Wagdy , Cacan Ercan , Liu Yuying , Eblen Scott T. , Greer Susanna F. , Hooks Shelley B.
Published: June 2021

Regulators of G‐Protein Signaling (RGS) Proteins suppress GPCR‐mediated growth and survival signaling in multiple cancers. We have shown that RGS10 is downregulated in ovarian cancer chemoresistance, and RGS10 expression levels alter ovarian cancer cell growth and sensitivity to cytotoxic drugs. This suggests that the suppression of RGS10 may contribute to ovarian cancer progression and the development of chemoresistance by indirectly amplifying GPCR‐mediated growth and survival signaling. The current study investigates the epigenetic regulation of RGS10 expression in ovarian cancer. RGS10 expression was reduced in clinical ovarian cancer and CAOV‐3 ovarian cancer cells compared to control immortalized ovarian surface epithelial (IOSE) cells. Histone acetylation at RGS10 promoters was decreased in CAOV‐3 compared to IOSE cells, with a corresponding increase in HDAC1 association. Similar loss of histone acetylation and increased HDAC1 binding was observed in chemoresistant versus chemosensitive ovarian cancer cells. Further, enhanced DNA methylation was observed in RGS10 promoter of chemoresistant cells. Our results suggest that epigenetic modifications correlate with the loss of RGS10 expression in ovarian cancer cells, and may contribute to the amplification of GPCR‐mediated growth and survival signaling. This research is funded by NIH and the Marsha Rivkin Center.
RGS2 protein degradation is mediated by a novel multiprotein E3 ligase containing Cullin 4b and F box 44
Authors: Sjogren Benita , Swaney Steven , Neubig Richard
Published: June 2021

Regulator of G protein signaling 2 (RGS2) is highly expressed in both heart and vascular smooth muscle and selectively regulates Gαq signaling. RGS2 KO mice are hypertensive, show increased responses to angiotensin and α‐adrenergic agonists as well as enhanced cardiomyocyte hypertrophy and death in heart failure models. RGS2 is rapidly degraded through the proteasome, but the exact mechanism for RGS2 protein degradation is not known. We hypothesize that stabilizing RGS2 protein expression could be a novel route in treating cardiovascular disease. RGS proteins are difficult drug targets. Therefore, identifying a more druggable protein within the degradation pathway could be a way to increase RGS2 protein function. The PathHunterTM ProLabel detection assay is a β‐galactosidase complementation assay that efficiently quantifies levels of proteins. Using this assay in a high‐throughput siRNA screen we identified several components of the ubiquitin protein degradation machinery and our results indicate that RGS2 is degraded through a cullin‐RING E3 ligase (CRL) containing Cullin 4B and F box protein 44. Furthermore, our results show that RGS2 and the closely related RGS4 utilize different degradation pathways. Increased understanding of RGS2 protein degradation should help identify new RGS2 modulators for cardiovascular disease. (Supported by NIH‐DA023252 and The Swedish Heart‐and Lung Foundation).
Repeated cannabinoid administration induces ΔFosB and sensitizes mu opioid receptor activity in the nucleus accumbens
Authors: Sim‐Selley Laura , Lazenka Matthew , Nestler Eric , Selley Dana
Published: June 2021

CB1 cannabinoid receptors (CB1Rs) mediate the central effects of Δ9‐tetrahydrocannabinol (THC), the main psychoactive constituent in marijuana. CB1Rs and endocannabinoids are expressed in striatum and regulate reward, motivation and motor activity. We reported that inducible transgenic expression of ΔFosB in D1/dynorphin medium spiny striatal neurons enhanced mu opioid receptor (MOR) signaling in the nucleus accumbens (NAc) and enhanced rewarding effects of morphine, without affecting MOR expression. Moreover, repeated THC administration induces the transcription factor ΔFosB in the NAc, but inducible transgenic expression of ΔFosB did not enhance CB1R signaling in this region. Here we show that repeated THC administration induced ΔFosB in both NAc and dorsal striatum. Interestingly, repeated THC administration also enhanced MOR‐mediated G‐protein activation in the NAc, whereas CB1R‐mediated G‐protein activity was not increased. Neither THC nor inducible transgenic expression of ΔFosB altered MOR‐mediated G‐protein activity in dorsal striatum. Finally, inducible transgenic expression of ΔcJun, a dominant negative inhibitor of ΔFosB‐mediated transcription, blocked THC‐induced enhancement of MOR‐mediated G‐protein activity in NAc. These results suggest that sensitization of MOR activity by repeated THC could be mediated by ΔFosB. Support: R01‐ DA014277 and R01‐DA030404 from NIDA
Effect of cannabinoid CB2 receptor agonism on learning and memory in a mouse model of photothrombosis
Authors: Myers Alyssa M , Ronca Richard D , Walker Ellen A , Tuma Ronald F , Ward Sara Jane
Published: June 2021

Stroke is associated with sensorimotor and cognitive deficits, and while rodent models of ischemic injury are commonly used to study infarct volume and sensorimotor deficits, relatively fewer studies have determined the cognitive impairments associated with these models. Previously we showed that selective cannabinoid CB2 agonists were able to attenuate ischemia injury using a mouse model of middle cerebral artery occlusion. The objective of this study was to extend findings on the neuroprotective properties of the CB2 agonist O‐1966 in a mouse model of photothrombotic stroke on sensorimotor and cognitive behaviors. Photothrombotic strokes or sham surgeries were induced in male C57BL/6 mice treated with the CB2 agonist O‐1966 (5.0 mg/kg IP) or vehicle at three timepoints. Post‐stroke, mice were tested in the rotarod assay to assess sensorimotor function. On day 6 mice were tested in a novel object recognition assay to assess episodic memory. Mice were then tested in an operant learning and memory assay on days 6 and 7. Photothrombotic stroke produced a deficit in novel object recognition and acquisition of an operant task, and these deficits were improved by administration of the cannabinoid‐2 agonist O‐ 1966. These findings suggest that the photothrombotic stroke procedure may model cognitive deficits seen in stroke patients and that these deficits in mice are reversed by the neuroprotective CB2 agonist O‐1966.
Eating high fat chow selectively impacts sensitivity to drugs acting on dopamine D3/D2 but not serotonin 2A receptors
Authors: Serafine Katherine Marie , France Charles P
Published: June 2021

Feeding conditions (e.g., type and quantity of food) can impact sensitivity to drugs acting on monoamine systems including direct‐and indirect‐acting dopamine (DA) receptor agonists; much less is known about the impact of different feeding conditions on drugs acting on serotonin (5‐HT) systems. Male Sprague‐Dawley rats had free access to high fat chow (34.3% fat; n = 8) or standard chow (5.7% fat; n = 7). Rats eating high fat chow gained more weight than rats eating standard chow and they became insulin resistant within 2 weeks. Moreover, rats eating high fat chow were more sensitive to yawning induced by quinpirole (DA receptor agonist; 0.0032–0.32 mg/kg) as compared with rats eating standard chow. Throughout the study, head twitching and changes to body temperature produced by the 5‐HT2A receptor agonist DOM (1‐(2, 5‐dimethoxy‐4‐methylphenyl)‐2‐aminopropane; 0.1–3.2 mg/kg) were not significantly different between groups. These results indicate that diet differentially impacts drugs acting on DA and 5‐ HT systems. Eating high fat chow selectively sensitized rats to the behavioral effects of a DA agonist, suggesting that eating high fat food might increase sensitivity to, and therefore vulnerability to abuse, drugs acting on dopamine systems (e.g., cocaine). CPF is supported by the NIDA Senior Scientist Award (K05 DA017918).
Survey on understanding, use and willingness to pay on front of pack labeling in Chile
Authors: Gregori Dario , Contreras Luis Valenzuela , Pérez Cecilia Bahamonde
Published: June 2021

Chile is undergoing a rapid nutritional transition. Nutrition labels on pre‐packaged foods have been used as a method to foster healthier eating habits, but their effect has not reached the expected results. In September 2012, a Computer Assisted Telephone Interview (CATI) was performed on a sample of Chilean consumers. By mean of a questionnaire developed by the authors, general data and understanding and the value of pack labeling, were investigated. 1282 interviews were performed, of whom 1262 reported to be normal weight. 55% of the respondents declare to regularly read labels. 62% of the interviewed indicated “per portion” as the favorite front‐of‐pack nutrition information. The 41% of the respondent wouldn't agree on paying more in order to get more information on the nutritional aspects. The majority of the interviewees stated to be able to distinguish and comprehend the information given on the labels, but their interpretation appeared not precise, weakening the impact of that information. Willingness to pay for a nutritional premium observed was low in absolute value, suggesting some attritions by the consumers in making healthier choices further the indications of nutritional labels.
The tryptophan hydroxylase 2 (Tph2) polymorphism C2432T mediates mRNA expression and responses to antidepressant treatment in a sex‐specific manner
Authors: Brookshire Bethany R , Lucki Irwin
Published: June 2021

The mechanisms behind successful treatment response in Major Depressive Disorder remain unclear. We examined whether a novel single nucleotide polymorphism (SNP) C2432T in the Tph2 gene mediates differences in response to SSRIs between two mouse strains: MRL/MpJ (MRL; SSRI‐responding, T/T) versus C57Bl/6J (C57; SSRI‐nonresponding, C/C) (Balu et al, 2009). We cross‐bred the MRL and C57 strains to isolate C2432T in the F2 generation and determined functionality using the response to SSRIs in the tail suspension test (TST). F2 T/T females showed an enhanced citalopram response (p<0.001, n=10), while males showed no genotype‐specific effects. The C2432T SNP also mediated Tph2 mRNA expression, with T/T animals showing increased expression in the midbrain (p<0.05, n=11–16). However, in response to chronic SSRI treatment, there was no difference by genotype in F2 generation animals in measures of hippocampal neurogenesis or novelty‐induced hypophagia behavior. The C2432T SNP may mediate serotonin involvement to acute antidepressant response in a sex‐specific manner, but did not mediate the effects of chronic antidepressant treatment.
Comparative Pharmacokinetics of the Complement Inhibitor CDX‐1135
Authors: Forsberg Eric , Boyer James M. , Gergel Lauren E. , Pilsmaker Catherine D. , Borrelli Kathleen M. , Round Sarah M. , Naylor Sarah R. , Marsh Henry C. , Keler Tibor , Thomas Lawrence J.
Published: June 2021

CDX‐1135 (sCR1) is a soluble, recombinant glycoprotein derived from the human complement regulatory protein Complement Receptor Type 1 (CR1, CD35, C3b/C4b receptor). CDX‐1135 inhibits the classical, alternative and lectin pathways of the complement cascade. CDX‐1135 is a single‐chain polypeptide of 1931 amino acids with approximately 35 kDa of N‐linked glycosylation. A pharmacokinetic study in rats was performed to compare four lots of CDX‐1135. Briefly, Sprague Dawley rats with jugular vein cannulas were administered a single intravenous injection of CDX‐1135 (10 mg/kg) in a lateral tail vein. Periodic blood samples were taken from the cannula, up to 96 hours after test article administration. Plasma was assayed for circulating levels of CDX‐1135 using an ELISA method. Lot A exhibited a mean AUClast of 1.32 × 106 hr*ng/ml compared to 1.85 × 106 hr*ng/ml for lot B, 2.22 × 106 hr*ng/ml for lot C, and 2.67 × 106 hr*ng/ml for lot D. Lot A exhibited a mean terminal half‐life of 22.6 hours compared to 24.9 hours for lot B, 21.8 hours for lot C, and 26.7 hours for lot D. These results can be explained by the rapid removal of CDX‐1135 molecules bearing asialo glycans, with the remaining molecules exhibiting very similar pharmacokinetics, as represented by the terminal half‐life. The pharmacokinetics of CDX‐1135, with slight variability between lots, is typical of many glycosylated recombinant proteins.
Alterations in Benzo(a)pyrene induced DNA damage via Organosulfide Compounds in MCF‐10A cells
Authors: Darling‐Reed Selina Faith , Nkrumah‐Elie Yasmeen , Hudson Alicia , Flores‐Rozas Hernan , Jett Marti , Hammamieh Rasha , Day Agnes , Oriaku Ebenezer , Reuben Jayne S
Published: June 2021

The Organosulfide compounds (OSCs) of garlic, Diallyl sulfide (DAS), Diallyl disulfide (DADS) and Diallyl trisulfide (DATS) have chemopreventive effects on several cancers including breast cancer. Previously we have shown that co‐exposure of benzo(a)pyrene(BaP), and OSCs has lead to a decrease in lipid peroxides thereby reducing DNA strand breaks while inducing cell cycle arrest in MCF‐10A cells. Therefore, these data led us to hypothesize that the mechanism of OSCs’ attenuation of BaP induced DNA damage in these cells occurs via alterations in the expression of cell cycle and DNA repair genes. To prove this hypothesis, CDKN1A (p21), BCL2L1, DNA polymerase beta and epsilon expression were determined via RTPCR and protein expression via western blot analysis in MCF‐10A cells after 24 hours using the following treatments: 0.1% DMSO control, 1 μM BaP alone, 60 μM OSC, or 1 μM BaP/60 μM OSC co‐exposure. After co‐exposure to DATS, a significant (p<0.05) increase was observed in p21, BCL2L, DNA polymerase beta, and epsilon gene expression when compared to control and BaP alone. DADS coexposure caused a significant (p<0.05) increase in DNA polymerase beta and p21 gene expression when compared to control and BaP alone. Protein expression studies indicated that coexposure to DAS, DADS and DATS significantly (p<0.05) increased DNA polymerase beta expression when compared to control and BaP alone. These results indicate that the chemopreventive effects observed in OSCs may be occurring via an increase in gene and protein expression of DNA repair genes involved in base excision repair.
Small molecule targeting of RhoC‐regulated gene transcription in metastatic, undifferentiated melanoma
Authors: Haak Andrew J , Wade Susan M , Bell Jessica L , Larsen Scott D , Verhaegen Monique , Lawlor Elizabeth R , Neubig Richard R
Published: June 2021

Melanoma is the most dangerous form of skin cancer with the majority of deaths arising from metastatic disease. Recent evidence implicates Rho‐activated gene transcription, mediated by the nuclear localization of the transcriptional coactivator, megakaryoblastic leukemia‐1 (MKL1), in melanoma metastasis. Here, we examine correlates of Rho expression and activity as well as markers of differentiation, migration, morphology, and tumorigenicity in a panel of human metastatic melanoma cell lines. Three melanoma lines with evidence of high Rho activity also show an aggressive and undifferentiated phenotype. These melanomas selectively overexpress RhoC but not RhoA and also have increased expression of mRNA for P75, a neural crest stem cell marker and decreased expression of melanocytic differentiation markers, MITF and TYR. To target the Rho/MKL transcriptional mechanism, we have developed a small molecule inhibitor of Rho‐regulated transcription. CCG‐203971, at low μM concentrations blocks nuclear localization of MKL, produces a more melanocyte‐like cellular morphology, decreases MKL target gene expression, and inhibits cellular migration of aggressive undifferentiated melanoma cells. These data link melanoma cell differentiation with Rho activity and support targeting the Rho/MKL transcriptional pathway as a novel approach to melanoma therapeutics. (Supported by NIH –T32‐GM007767)
Time course of changes in sympathetic nerve activity during development of hypertension in spontaneously hypertensive rats
Authors: Mineyama Naoko , Yoshimoto Misa , Shirai Mikiyasu , Miki Kenju
Published: June 2021

Potential contributions of sympathetic nerve activity to the development of hypertension were studied in the spontaneously hypertensive stroke prone rat (SHRSP). Male SHRSPs were chronically instrumented with bipolar electrodes for measurements of renal (RSNA) and lumbar sympathetic nerve activity (LSNA), and a telemeter was used for measurement of arterial pressure (AP). The time course of changes in AP, heart rate (HR), RSNA, and LSNA were measured continuously and simultaneously from 8 to 12 weeks of age in SHRSPs. AP progressively increased throughout 8–12 weeks in SHRSPs. Diurnal amplitude (difference between daily peak and nadir values) for mean AP gradually increased throughout the experimental period. HR gradually decreased throughout the experimental period without changes in diurnal amplitude for HR. We succeeded in measuring RSNA and LSNA over 4 weeks in several SHRSPs. RSNA and LSNA did not appear to increase in association with the increase in AP over 8–12 weeks of age. Therefore, the contribution of sympathetic nerve activity to the development of hypertension in the SHRSP remains unclear. JSPS Grant.
Muscle‐specific deletion of mTORC2 (Rictor) blocks insulin stimulated Akt Ser 473 phosphorylation and impairs submaximal but not maximal insulin induced glucose uptake
Authors: Kleinert Maximilian , Sylow Lykke , Jensen Thomas Elbenhardt , Oxboll Anne‐Julie , Richter Erik
Published: June 2021

Objective

To test whether Rictor and Akt Ser437 phosphorylation is necessary for insulin‐stimulated glucose uptake in skeletal muscle.

Methods

EDL muscle from muscle‐specific Rictor knock‐out mice (mKO) were incubated ex vivo with or without submaximal (100μU/ml) or maximal (100mU/ml) insulin concentrations. Akt Ser473 phosphorylation served as mTORC2 activity readout and muscle glucose uptake was measured with tritium‐labeled 2‐deoxyglucose.

Results

Submaximal and maximal insulin stimulation increased Akt Ser437 phosphorylation 4‐fold and 21‐fold, respectively in EDL from WT mice (p < 0.01), but was blocked completely in mKO Rictor EDL. Akt1 and Akt2 expression in mKO Rictor muscle were reduced by 40% and 60%, respectively (p < 0.001). Conversely, expression of TRB3, a negative regulator of Akt activity, was increased 1.6‐fold (p < 0.05) in mKO Rictor muscle. Glucose uptake increased 2‐fold in WT mice with both submaximal and maximal insulin concentrations (p < 0.05). In mKO muscle submaximal insulin‐induced glucose uptake was completely blocked but was normal during maximal insulin stimulation.

Conclusion

Deletion of Rictor in muscle impairs Akt expression and blocks Akt Ser437 phosphorylation during insulin stimulation. Rictor and Akt Ser 473 phosphorylation are necessary for increasing muscle glucose uptake at submaximal but not maximal insulin concentrations.
Macula densa nitric oxide contributes to anomalous tubuloglomerular feedback in subtotal nephrectomy rats on high salt diet
Authors: Singh Prabhleen , Pham Hai , Khang Ser , Thomson Scott
Published: June 2021

It is more work for the kidney to conserve NaCl than to excrete it. Tubuloglomerular feedback (TGF) normally contributes to NaCl conservation by preventing the distal NaCl delivery from increasing. The only known exception to this is the rat fed high NaCl diet (HS)) after subtotal nephrectomy (STN) in which case TGF exerts a positive feedback effect, which amplifies, rather than attenuates, the impact of SNGFR on distal delivery. NaCl‐dependent nitric oxide (NO) from the macula densa is known to blunt normal TGF‐mediated vasoconstriction. Present experiments were conducted to test hypothesis that the anomalous TGF response of STN to HS is mediated by excess NO from the macula densa. Male Wistar rats were fed HS from the time of STN or sham surgery. TGF responses were measured by micropuncture 8 days later, perfusing Henle's loop from late proximal tubule at 8 and 50–60 nl/min with artificial tubular fluid (ATF) ± NOS blocker (LNMMA 10−4M) and measuring single nephron GFR (SNGFR) by 3H inulin clearance in fluid collected from late proximal tubules.

GFR (ml/min)
Urine flow (μl/min)
SNGFR (nl/min)

LOH perfusion
N/A
N/A
Low
High
ΔSNGFR†

STN+ATF (n=15)
0.6±0.1
39±4
54±4
59±4
−5±4

STN+LNMM A (n=20)
55±4
47±4
8±4

Sham+ATF (n=10)
3.2±0.7*
34±6
50±5
24±5
26±5

Sham+LNMM A (n=19)
43±4
25±4
18±4

P<0.01 vs. STN.

P<0.02 for effect of LNMMA on TGF response in STN vs. Sham.

Local NOS blockade abolishes anomalous TGF response in STN fed HS, but does not restore the TGF response to the magnitude seen in Shams fed HS. Anomalous TGF in STN fed HS contributes to a broad effort to achieve salt balance under extreme conditions. A portion of this is mediated by increased NOS activity in the juxtaglomerular apparatus.
Angiotensin II (Ang II)‐pretreated female but not male rats are protected from pressor response and sympathetic activation to 2% saline drinking
Authors: Wei Tianyi , Clayton Sarah C , Xue Baojian , Hay Meredith , Johnson Alan Kim
Published: June 2021

Growing evidence suggests sex differences in the development of hypertension. Previous work in our lab indicated male rats display a greater pressor response to 2% saline when sensitized with Ang II, so‐called “induced salt sensitivity”. In the current study, we hypothesized female rats are resistant to induced salt sensitivity. To test this hypothesis, blood pressure (BP) of female rats was monitored continuously with telemetry devices. Following an Induction‐Delay‐Expression (I‐D‐E) design, after one week recovery and one week baseline recording (B), rats received a subpressor dose of Ang II (10ng/kg/min, sc) via osmotic pumps for 7 days (I) and were then rested an additional 7 days to metabolize any exogenous Ang II (D). No difference in BP was detected during B, I, or D in these animals. During E, with 2% saline as the sole drinking fluid, no change in BP was detected in either control (97±2 mmHg, B, vs. 100±3 mmHg, E) or Ang II‐pretreated rats (99±2 mmHg, B, vs. 102±3 mmHg, E). To determine the influence of sympathetic tone on baseline BP, ganglionic blocker hexamethonium (30 mg/kg, ip) elicited similar reductions in BP in both control and pre‐treated Ang II female rats throughout the course of the study (B,I,D,E). These results suggest that female rats are protected from induced salt sensitivity, possibly through a resistance to sympathetic activation.
Altered thick ascending limb function in aging female mice consuming high quantities of fructose‐sweetened water
Authors: Li Lijun , Yunghans Allison , Awan Shehar‐Bano , Alamri Lamia , Ecelbarger Carolyn
Published: June 2021

Fructose (Frc) is metabolized differently from glucose, i.e., with initial metabolism by ketohexokinase (KHK), an enzyme associated with ATP depletion. To test whether a diet enriched in Frc might impair energy‐intensive actions of the renal thick ascending limb (TAL), we evaluated TAL function and protein expression in response to 4‐weeks of 10% Frc in drinking water in young (Y, 3 months) male (M) and female (F) and mid‐aged F (A, 12 months) mice. Frc resulted in, on average, 11% lower kidney weights, regardless of age or sex. In addition, Frc caused a significant reduction in urine concentrating capacity, observed most dramatically in the aged females (F). Urine osmolality was (% of control): 95, 75, and 44 in YMFrc, YFFrc, and AFFrc, respectively. In contrast, Frc increased urine diluting capacity. However, this protective adaptation was attenuated in the AFFrc (urine osmolality % of C): 77 (YMFrc), 76 (YFFrc), 87 (AFFrc). Western blotting revealed 2–5X increased kidney cortex KHK expression in Frc groups, with the increase greatest in YFFrc. Frc resulted in a modest 20–60% increase in band density for the Na‐K‐2Cl cotransporter (NKCC2), the major apical sodium chloride cotransporter of the TAL, but only in Y mice. In the AFFrc it was reduced 30%. In summary, diets enriched in Frc may alter the ability of the TAL to effectively dilute and concentrate urine. Aging subjects may be especially vulnerable. NIH DK082507.
The effect of gender on sympathetic neural responses to cold pressor testing in hypertensive seniors
Authors: Hendrix Joseph Maxwell , Bivens Tiffany , Best Stuart , Okada Yoshiyuki , Levine Benjamin D. , Fu Qi
Published: June 2021

Previous studies have suggested the possibility of augmented sympathetic neural activity among elderly women versus men, and among hypertensives versus normotensives. The purpose of this study was to ascertain whether hypertensive women had an augmented muscle sympathetic nerve activity (MSNA) to cold pressor testing (CPT) than hypertensive men. We compared MSNA, heart rate, and blood pressure in response to and recovery from 2‐min CPT in 13 hypertensive elderly (65–80 yrs) men, 10 hypertensive elderly women, 11 normotensive elderly men and 10 normotensive elderly women. Baseline MSNA was not different among groups. Women had significantly lower MSNA during CPT (83+/−2.2 vs. 92+/−2.0 bursts/100 beats) than men. Diastolic blood pressure was also significantly lower among hypertensive women compared to hypertensive men during CPT (84+/−3.5 vs. 96+/−3.1 mmHg). These results suggest that hypertensive women have blunted MSNA to cold pressor testing versus hypertensive men, which may contribute to the lower diastolic pressure in women.
Heart rate variability and cardiorespiratory fitness in African American men
Authors: Herron Robert Louis , Esco Mike R
Published: June 2021

Heart rate variability (HRV) has become a widely used indicator of cardiovascular autonomic control. Previous research has shown HRV to be greater in subjects with higher levels of cardiorespiratory fitness. However, the association of HRV and cardiorespiratory fitness in African American (AA) subjects is not known. This investigation aimed to determine if norm‐referenced cardiorespiratory fitness groupings would reflect differences in HRV in AA men. Forty college‐aged AA men had their resting HRV assessed via electrocardiography and later completed a graded maximal exercise treadmill test. Individuals were stratified according to VO2 peak, those above 43.9 ml·kg−1·min−1(50th percentile for college‐aged men) (Group A) and those below (Group B). HRV differed between groups A and B for low frequency (LFnu; 32.5 ± 7.4 ms2 vs. 37.9 ± 8.6 ms2), high frequency (HFnu; 52.3 ± 7.6 ms2 vs. 47.5 ± 6.6 ms2), and LFnu:HFnu (0.6 ± 0.2 vs. 0.8 ± 0.2) respectively (P < 0.05). These data suggest that differences in cardiorespiratory fitness levels reflect differences in autonomic control of the cardiovascular system in college‐aged AA males. Supported by Auburn University Montgomery & The University of Alabama.
Distension of central great vein decreases sympathetic outflow in humans
Authors: Cui Jian , Gao Zhaohui , Blaha Cheryl , Mast Jessica , Herr Michael D. , Sinoway Lawrence I.
Published: June 2021

Classic canine studies suggested that central great vein distension evoked a reflex tachycardia (“Bainbridge reflex”). Our recent reports suggest that distension of human forearm veins evokes reflex increases in muscle sympathetic nerve activity (MSNA) and blood pressure (BP). It is unknown whether these responses are evoked by the same reflex system. We hypothesized that distension in inferior vena cava (IVC) in humans would not evoke tachycardia, but lead to a decrease in MSNA. IVC distension (echocardiography) was induced with 2‐min head‐down tilt (HDT, ~13°, N=13) and 2‐min lower body positive pressure (LBPP, 40 mmHg, N=10) in 2 visits. HDT induced IVC distension (20.6±1.3 to 23.1±1.4 mm, P<0.001), and a small increase in mean BP (Finometer, 82.4±2.4 to 84.7±2.7 mmHg, P=0.005), and a significant decrease in MSNA (14.5±2.0 to 9.3±2.0 bursts/min, P<0.001, N=10). HR did not change significantly (61.6±3.4 to 61.1±3.3 beats/min. P=0.37) during the HDT. LBPP also induced IVC distension (Δ2.4±0.2 mm, P<0.001), a small increase in BP (Δ2.0±0.7 mmHg, P<0.01), no increase in HR (P=0.34). These data suggest that central venous distension does not lead to tachycardia but a decrease in systemic sympathetic outflow in humans. Thus, central venous distension and peripheral venous distension evoke high dissimilar autonomic responses. These reflexes (peripheral vs. central venous distension) are not evoked by the same reflex mechanism. Supported by P01 HL096570 and UL1 TR000127.
Cerebrovascular reactivity and implications for understanding the pathophysiology of multiple sclerosis
Authors: Pucci Olivia , Battisti‐Charbonney Anne , Fierstra Jorn , Mandell Daniel M , Mikulis David , Poublanc Julien , Crawley Adrian , Fisher Joseph , Duffin James
Published: June 2021

Multiple sclerosis (MS) is a severe neurological disease commonly diagnosed in young adults. Recent controversial publications attribute the inflammation, sclerosis, and degenerative lesions to venous insufficiency. We recently found characteristic reductions in cerebrovascular reactivity (CVR) in the presence of venous congestion caused by other neurological disorders. We therefore hypothesize that CVR may also be reduced in patients with MS. A computer‐controlled gas blender (RespirAct™, TRI, Canada) was used to precisely target normoxic PETCO2 changes between 40 to 50 mmHg in 7 MS subjects with varying type and severity. BOLD MRI was performed simultaneously as an indirect measure of changes in cerebral blood flow. CVR, defined on a voxel‐wise basis as %ΔBOLD signal/ΔPETCO2, was color coded and superimposed on anatomical scans to form CVR maps. Each CVR map was compared voxel‐by‐voxel with a CVR atlas generated from 37 healthy subjects. Contrary to our hypothesis, CVR in MS subjects was greater than the healthy cohort. The degree of hyper‐reactivity correlated with the severity of MS. Regions of increased CVR may reflect the confounding dependency of BOLD MRI on cerebral blood volume which could be increased due to insufficient venous drainage. However, it may actually reflect an increased flow response to hypercapnia which overwhelms the altered venous draining system leading to venous congestion.
Aerobic Training (T) Improves the Integrity Blood Brain Barrier (BBB) in Spontaneously Hypertensive Rats (SHR)
Authors: Buttler Leila , Jordão Maria Tereza , Michelini Lisete Compagno
Published: June 2021

It is well known that hypertensive rats exhibited a deficient BBB. To evaluate the combined effect of hypertension and T on BBB integrity within autonomic areas, SHR were submitted to treadmill T (55% of maximum capacity, 1h/day, 5 d/week) or kept sedentary (S) for 2 month. After hemodynamic measurements at rest, rats were anesthetized for carotid infusion with dextrans FITC‐10 kDA + RHO‐70 kDA (286μl/100g). Twenty minutes later, brains were removed, post‐fixed and cryoprotected; sequential slices (30 μm) of the hypothalamic paraventricular nucleus (PVN) were acquired in a fluorescent microscope and processed by Image J analysis. BBB integrity was assessed by degree of FITC leakage into the extravascular CNS space. Eight‐weeks of T caused a significant MAP and HR reduction (155±6 mmHg, 357±7 b/min vs. 164±8 mmHg, 397±13 b/min before T). Hemodynamic changes were accompanied by a marked reduction on dye leakage area within the ventromedial and posterior PVN (on average from 16±0.5% to 7±1.5% after T, corresponding to a reduction of 56%). Data showed a novel beneficial effect of training to reduce BBB leakage in hypertensive rats. This adaptive response may contribute to the improvement of brain perfusion after training. Financial Support: FAPESP