Gastric bypass in female rats lowers concentrated sugar solution intake and preference without affecting brief-access licking after long-term sugar exposure

In rodents, Roux-en-Y gastric bypass (RYGB) decreases intake of, and preference for, foods or fluids that are high in sugar. Whether these surgically induced changes are due to decreases in the palatability of sugar stimuli is controversial. We used RYGB and sham-operated (SHAM) female rats to test the influence of prolonged ingestive experience with sugar solutions on the motivational potency of these stimuli to drive licking in brief-access (BA) tests. In experiment 1, RYGB attenuated intake of, and caloric preference for, 0.3 M sucrose during five consecutive, 46-h two-bottle tests (TBTs; sucrose). A second series of TBTs (5 consecutive, 46-h tests) with 1.0 M sucrose revealed similar results, except fluid preference for 1.0 M sucrose also significantly decreased. Before, between, and after the two series of TBTs, two sessions of BA tests (30 min; 10-s trials) with an array of sucrose concentrations (0 and 0.01–1.0 M) were conducted. Concentration-dependent licking and overall trial initiation did not differ between surgical groups in any test. In a similar experimental design in a second cohort of female rats, 0.6 and 2.0 M glucose (isocaloric with sucrose concentrations in experiment 1) were used in the TBTs; 0 and 0.06-2.0 M glucose were used in the BA tests. Outcomes were similar to those for experiment 1, except RYGB rats initiated fewer trials during the BA tests. Although RYGB profoundly affected intake of, and caloric preference for, sugar solutions and, with high concentrations, fluid preference, RYGB never influenced the motivational potency of sucrose or glucose to drive concentration-dependent licking in BA tests.

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Methamphetamine-induced changes in myocardial gene transcription are sex-dependent

BMC Genomics ◽

10.1186/s12864-021-07561-x ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Hasitha Chavva ◽

Daniel A. Brazeau ◽

James Denvir ◽

Donald A. Primerano ◽

Jun Fan ◽

...

Keyword(s):

Gene Expression ◽

Ischemic Injury ◽

Female Rats ◽

Dependent Effect ◽

Methamphetamine Use ◽

Number Of Genes ◽

Myocardial Ischemic Injury ◽

Induced Changes ◽

Myocardial Gene Expression

Abstract Background Prior work demonstrated that female rats (but not their male littermates) exposed to methamphetamine become hypersensitive to myocardial ischemic injury. Importantly, this sex-dependent effect persists following 30 days of subsequent abstinence from the drug, suggesting that it may be mediated by long term changes in gene expression that are not rapidly reversed following discontinuation of methamphetamine use. The goal of the present study was to determine whether methamphetamine induces sex-dependent changes in myocardial gene expression and whether these changes persist following subsequent abstinence from methamphetamine. Results Methamphetamine induced changes in the myocardial transcriptome were significantly greater in female hearts than male hearts both in terms of the number of genes affected and the magnitude of the changes. The largest changes in female hearts involved genes that regulate the circadian clock (Dbp, Per3, Per2, BMal1, and Npas2) which are known to impact myocardial ischemic injury. These genes were unaffected by methamphetamine in male hearts. All changes in gene expression identified at day 11 returned to baseline by day 30. Conclusions These data demonstrate that female rats are more sensitive than males to methamphetamine-induced changes in the myocardial transcriptome and that methamphetamine does not induce changes in myocardial transcription that persist long term after exposure to the drug has been discontinued.

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Long-term intermittent cold exposure affects peri-ovarian adipose tissue and ovarian microenvironment in rats

10.21203/rs.3.rs-346471/v1 ◽

2021 ◽

Author(s):

Li Zhang ◽

Gaihong An ◽

Shuai WU ◽

Jing Wang ◽

Danfeng Yang ◽

...

Keyword(s):

Adipose Tissue ◽

Cold Exposure ◽

Ovarian Function ◽

Exposed Group ◽

Female Rats ◽

Synthesis Rate ◽

Control Group ◽

Female Reproductive Health ◽

Induced Changes

Abstract Background: This study aimed to investigate the effects of cold exposure on peri-ovarian adipose tissue (POAT) and the relationship between POAT changes and ovarian function, to gain a deeper understanding of the mechanisms associated with cold exposure-induced changes in female reproductive health. Methods: Twenty female rats with regular estrus cycles were randomly divided into two groups: (1) the cold exposure group, which was exposed to –10°C, for 4 hours/day, for two weeks, and (2) the control group, which was maintained at 23 ± 1°C. Results: Cold exposure can increase serum E2 and FSH levels, and reduce AMH hormone levels, and cause the numbers of primary and secondary follicles in the cold-exposed group were significantly higher than those in the control group. Meanwhile, cold-stress-induced browning-related genes, including UCP1, PGC -1a, PRDM16, Fndc5 were upregulated in POAT, and the number of mitochondria in the cold-exposed group was significantly increased. Under cold exposure, the level of adipokines, including APDN, Lep, AMPK were significantly upregulated in POAT. FST was also upregulated in POAT, whereas MST, an AMPK inhibitor, was downregulated. The E2 synthesis rate-limiting-enzymes Cyplla1 and Cyp19 were upregulated in POAT. Conclusion: Cold exposure caused abnormal follicle development and promoted the browning of POAT. POAT browning was accompanied by the activation of the AMPK-PGC1α-Fndc5 pathway.

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Effects of Polyamines on the Release of Gonadotropin-Releasing Hormone and Gonadotropins in Developing Female Rats

Experimental Biology and Medicine ◽

10.1177/153537020222700408 ◽

2002 ◽

Vol 227 (4) ◽

pp. 276-281 ◽

Cited By ~ 5

Author(s):

Sandra M. Thyssen ◽

Pablo F. Hockl ◽

Astrid Chamson ◽

Victoria A.R. Lux-Lantos ◽

Carlos Libertun

Keyword(s):

Inhibitory Effect ◽

Female Rats ◽

Gonadotropin Secretion ◽

Cell Functions ◽

High K ◽

Multiple Cell ◽

Old Rats ◽

High Concentrations ◽

Induced Changes

Polyamines, putrescine (PUT), spermidine (SPD), spermine (SPM), and agmatine (AGM), are polycationic amines related to multiple cell functions found in high concentrations during the development of hypothalamus and pituitary. In previous works, we demonstrated that α-difluoromethylornithine (DFMO), an inhibitor of polyamines biosynthesis, induced a delay in puberty of female rats, accompanied by high, sustained follicle-stimulating hormone (FSH) levels during the infantile period. Also, DFMO treatment induced changes in polyamine concentration both in hypothalamus and pituitary of rats, mainly a decrease of PUT and SPD, an increase in SPM, and no change in AGM. In the present work, we investigated the direct effects of polyamines on the secretion of hypothalamic GnRH and pituitary gonadotropins in 6- and 15-day-old female rats. In 6-day-old animals, In vitro incubations with PUT, SPD, and AGM of hypothalami or anterior pituitaries were able to inhibit GnRH, FSH, and leutinlzing hormone (LH) secretion, respectively. SPM showed a nonspecific transient inhibitory effect on FSH. When challenged with either high K+ (hypothami) or GnRH (pituitaries), the tissues incubated in the presence of polyamines showed no differences when compared with their controls. No effects of polyamines in 15-day-old rats in either tissue were observed. Pituitary cell cultures of 6-day-old animals incubated with DFMO for 4 days showed a significant increase in FSH, but not in LH. We conclude that high PUT, SPD, and AGM levels during the first 10 days of life are important for the development of the hypothalamic-hypophyseal unit, probably related to an inhibitory effect on GnRH and gonadotropins. Therefore, polyamine participation, especially PUT and SPD, is of importance in the regulation of GnRH and gonadotropin secretion in the neonatal and infantile periods, critical stages in the establishment of sexual differentiation.

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Long-term-follow-up of patients with gastric bypass surgery secondary to craniopharyngioma associated hypothalamic obesity

Endocrine Abstracts ◽

10.1530/endoabs.70.ep341 ◽

2020 ◽

Author(s):

Hannes Beiglböck ◽

Paul Fellinger ◽

Tamara Ranzenberger-Haider ◽

Greisa Vila ◽

Anton Luger ◽

...

Keyword(s):

Gastric Bypass ◽

Bypass Surgery ◽

Gastric Bypass Surgery ◽

Hypothalamic Obesity ◽

Long Term Follow Up

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Presence of Liver Steatosis Is Associated With Greater Diabetes Remission After Gastric Bypass Surgery

10.2337/figshare.13166255 ◽

2020 ◽

Author(s):

Roman Vangoitsenhoven ◽

Rickesha Wilson ◽

Deepa V Cherla ◽

Chao Tu ◽

Sangeeta R Kashyap ◽

...

Keyword(s):

Gastric Bypass ◽

Metabolic Surgery ◽

Gastric Bypass Surgery ◽

Liver Steatosis ◽

Multivariable Analysis ◽

Diabetes Remission ◽

Independent Association ◽

Glycemic Outcomes ◽

Design And Methods

Objective: Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance (IR) and beta-cell dysfunction. Ectopic fat accumulation in liver and muscle causes IR. Since bariatric and metabolic surgery significantly improves fatty liver disease, <a>we hypothesized that coexistence of liver steatosis (i.e., when hepatic IR contributes in T2DM) would be associated with greater diabetes improvement after surgery.</a> Research design and methods: A total of 519 patients with T2DM who underwent Roux-en-Y gastric bypass and simultaneous liver biopsy and had a minimum 5-year follow-up were analyzed to assess the independent association between biopsy-proven liver steatosis and postoperative long-term diabetes remission (glycated hemoglobin < 6.5% off medications). Results: Of the 407 patients with biopsy-proven liver steatosis, long-term diabetes remission was achieved in 211 (52%) patients, compared with 44/112 (39%) remission in patients without steatosis (P=0.027). In multivariable analysis, presence of liver steatosis was an independent predictor of long-term diabetes remission (odds ratio 1.96, [95% confidence interval 1.04 – 3.72], P=0.038). Hepatocyte ballooning, lobular inflammation, or fibrosis at baseline did not predict diabetes remission. Conclusion: This study, for the first time, suggests that in patients with T2DM who are considering bariatric and metabolic surgery, coexistence of liver steatosis is associated with better long-term glycemic outcomes. Furthermore, our data suggest that there are different variants of T2DM wherein metabolic responses to surgical weight loss are different. A subgroup of patients whose T2DM is characterized by the presence of hepatic steatosis (presumably associated with worse IR) experience better postoperative metabolic outcomes.

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Registered Report: Transcriptional Analysis of Savings Memory Suggests Forgetting Is Due to Retrieval Failure

10.31234/osf.io/h59jv ◽

2020 ◽

Author(s):

Robert Calin-Jageman ◽

Irina Calin-Jageman ◽

Tania Rosiles ◽

Melissa Nguyen ◽

Annette Garcia ◽

...

Keyword(s):

Memory Trace ◽

Aplysia Californica ◽

Transcriptional Response ◽

Transcriptional Analysis ◽

Retrieval Failure ◽

Initial Learning ◽

Rigorous Test ◽

Stage 1 ◽

Induced Changes

[[This is a Stage 2 Registered Report manuscript now accepted for publication at eNeuro. The accepted Stage 1 manuscript is posted here: https://psyarxiv.com/s7dft, and the pre-registration for the project is available here (https://osf.io/fqh8j, 9/11/2019). A link to the final Stage 2 manuscript will be posted after peer review and publication.]] There is fundamental debate about the nature of forgetting: some have argued that it represents the decay of the memory trace, others that the memory trace persists but becomes inaccessible due to retrieval failure. These different accounts of forgetting lead to different predictions about savings memory, the rapid re-learning of seemingly forgotten information. If forgetting is due to decay, then savings requires re-encoding and should thus involve the same mechanisms as initial learning. If forgetting is due to retrieval failure, then savings should be mechanistically distinct from encoding. In this registered report we conducted a pre-registered and rigorous test between these accounts of forgetting. Specifically, we used microarray to characterize the transcriptional correlates of a new memory (1 day after training), a forgotten memory (8 days after training), and a savings memory (8 days after training but with a reminder on day 7 to evoke a long-term savings memory) for sensitization in Aplysia californica (n = 8 samples/group). We found that the re-activation of sensitization during savings does not involve a substantial transcriptional response. Thus, savings is transcriptionally distinct relative to a newer (1-day old) memory, with no co-regulated transcripts, negligible similarity in regulation-ranked ordering of transcripts, and a negligible correlation in training-induced changes in gene expression (r = .04 95% CI [-.12, .20]). Overall, our results suggest that forgetting of sensitization memory represents retrieval failure.

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