bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glucose mediates upregulation of Cck expression independent of cAMP signaling
Authors: Williams Rashaun A. , Flowers Matthew , Davis Dawn B. 
Published: May 2022

Cholecystokinin (CCK) is a gut peptide hormone that is also produced by pancreatic β‐cells under conditions of metabolic stress and obesity. Treatment with exogenous CCK can alleviate obesity‐related diabetes in animal models without significant side effects. We have established that CCK is expressed primarily in the pancreatic β‐cell and that CCK is highly upregulated in ob/ob mice. We have also shown that elevated cellular cAMP stimulates β‐cell CCK expression and secretion. However, the specific islet cell types that express CCK and the regulation of Cck transcription in the islet has not been thoroughly explored. A more recent study from our lab showed that high glucose concentrations can upregulate Cck expression in mouse islets and human islets. We hypothesize that Cck expression is upregulated in response to various diabetogenic conditions and that CCK upregulation by glucose can occur independent of cAMP activation.Islets from 16‐week‐old C57BL/6J mice were harvested for use in a dose‐dependent 24‐hour study using different glucose concentrations: No glucose, 2.5mM, 7mM, 11mM & 25mM. After 24‐hour treatment, islets were collected for RNA isolation and cDNA synthesis to identify changes in Cck mRNA expression after incubation with different glucose concentrations. Cck mRNA levels were elevated 4‐8 fold in islets treated with 25 mM glucose compared to islets treated with 0 to 11mM glucose. Notably, the hypoglycemic treatment of no glucose and 2.5mM showed a 4‐fold increase when compared to the 7mM and 11mM treatments. Following this experiment, we wanted to determine if high glucose would still increase Cck mRNA expression after inhibiting cAMP. Islets were pre‐incubated for 45 minutes with 10nM sulprostone, which activated prostaglandin E3 (EP3) receptor and inhibits adenylate cyclase. After inhibition of cAMP, we incubated the islets at 2.5mM and 25mM glucose concentrations like the prior experiment and observed changes in Cck mRNA expression. After treatment with sulprostone, we are still able to see a significant increase in Cck mRNA expression in islets treated with 25mM glucose compared to those treated with 2.5mM glucose, even with cAMP inhibition.This data suggests that there are alternative pathways that could lead to CCK upregulation in the pancreatic islet independent of cAMP. It also shows that hypoglycemia may also increase Cckexpression, which suggests that CCK is upregulated in response to several forms of metabolic stress. We can further explore the effectiveness of glucose to increase CCK expression by treating islets with cycloheximide and deoxyglucose to determine if glucose metabolism is required for upregulation of Cck.This information will help with our general understanding of how CCK functions in pancreatic islet and how Cck transcription is regulated through signaling pathways and transcriptional networks that regulate β‐cell function and identity under diabetogenic conditions.
Sex‐differences and cell type‐specific alterations in brain Bcl2 expression after transient focal cerebral ischemia in aged mice
Authors: Griffiths Brian , Xu Lijun , Stary Creed 
Published: May 2022

IntroductionStroke remains the second leading cause of death worldwide and remains the primary cause of long‐term disability in the US. To date, the only pharmacological treatment for stroke remains tissue plasminogen activator. A major factor for translational failure is likely overwhelming use of young male rodents despite the fact that stroke occurs predominantly in aged populations and is a sexually dimorphic disease with sex differences in incidence, prevalence, and outcomes. The Bcl2 family is known to play an important role in the evolution of injury following cerebral ischemia. Overexpression of pro‐survival Bcl2 protects against cerebral ischemia in vivo and in vitro. In the present study we explored whether Bcl2 could play a role in known age‐ and sex‐related differences in stroke.MethodsAll studies were conducted in accordance with National Institutes of Health guidelines for the use of experimental animals, with protocols approved by the Stanford Animal Care and Use Committee. Transient focal cerebral ischemia was induced by suture occlusion of the middle cerebral artery (MCAO) for 1h in 20 month‐old male and female C57BL/6 mice. Sham surgery consisted of anesthesia and internal carotid exposure without suture occlusion (n=6 per group). Histological assessment: Animals were sacrificed at post‐MCAO days 1, 3, and 30 (n=6 per group, per time point), and brains fixed with 4% phosphate‐buffered paraformaldehyde for stereological analysis. Fixed sections were stained for Bcl2, the astrocyte marker glial fibrillary acidic protein (GFAP), and the mature neuronal marker NeuN. An observer blinded to conditions quantified the cell‐type specific relative intensity of Bcl2 from maximum projection Z‐stack images.ResultsIn sham animals Bcl2 expression was significantly (p<0.05) higher in both female astrocytes and neurons relative to male. After MCAO male neuronal Bcl2 expression was significantly depressed from days 1 until 30, while female neuronal Bcl2 remained unchanged. Conversely in astrocytes, female Bcl2 expression decreased significantly at post‐injury days 1 and 3, but recovered by day 30, while male astrocyte Bcl2 decreased by day 3 and remained significantly repressed at day 30.ConclusionsBaseline differences in Bcl2 expression between aged males and females, and cell‐type specific differences in post‐injury Bcl2 expression may account for age‐ and sex‐related differences in injury outcome from stroke. Bcl2 may represent a therapeutic target for stroke for both sexes in clinically‐relevant aged populations.
The Evolution of Language‐Related Long Association Pathways: A Comparative Study Between Humans and Rhesus Macaques
Authors: Alatorre Warren Jose Luis , Drak Lilit , Shalwani Saba , Jung Homoon , Ortug Alpen , Takahashi Emi 
Published: May 2022

The human brain stands out from other primates for its large size. After the split with our last common ancestor (LCA) with chimpanzees—our closest living relative—, the hominin brain expanded threefold, and the frontal and parietal operculum underwent substantial morphological reorganization, likely reflecting language acquisition in our species. The increase of brain size was not homogeneous: the inferior frontal and the parietal areas had a disproportionally large expansion while the occipital lobe retained its absolute size. These evolutionary changes are even more pronounced when human brains are compared to those of Old World monkeys. However, the amount of change in long association pathways within these highly modified regions is not well understood.This study aims to identify differences and similarities in homologous pathways of the human language network in the macaque brain. We hypothesize that language‐related pathways projecting to/from the inferior frontal and parietal areas will exhibit substantial reorganization in humans.Using state‐of‐the‐art, publicly available diffusion MRI data of a healthy (in vivo) adult human (MGH‐USC) [1] and 6 ex vivo rhesus macaque (Oxford University, PRIME‐DE) [2] brains, we reconstructed and virtually dissected in DSI Studio three association pathways: the arcuate fasciculus (AF), the frontal aslant tract (FAT), and the parietal‐projecting portion of the extreme capsule (pEmC). We show that the course and terminal projections of the FAT (inferior frontal and supplementary motor area) and the pEmC (superior parietal lobule and frontal cortical areas) are highly evolutionarily preserved in both species despite their crucial role in language in humans. In stark contrast, the AF underwent a major modification in its posterior segment, as previously reported.Our results suggest that evolutionary changes in the regional volumetric morphology of the brain do not necessarily imply similarly large changes in the relative volumes and trajectories of underlying white matter pathways. In addition, the current results suggest that the structural basis of human language functions already existed, at least to some extent, in the LCA with macaques. Functional and behavioral studies are needed to understand the role of this white matter network in both species.References[1] Wang, F., Dong, Z., Tian, Q., Liao, C., Fan, Q., Hoge, W.S., Keil, B., Polimeni, J.R., Wald, L.L., Huang, S.Y. and Setsompop, K., 2021. In vivo human whole‐brain Connectom diffusion MRI dataset at 760 µm isotropic resolution. Scientific Data, 8(1), pp.1‐12.[2] Milham, M.P., Ai, L., Koo, B., Xu, T., Amiez, C., Balezeau, F., Baxter, M.G., Blezer, E.L., Brochier, T., Chen, A. and Croxson, P.L., 2018. An open resource for non‐human primate imaging. Neuron, 100(1), pp.61‐74.
Modulatory role of 17α‐estradiol (non‐feminizing estrogen) on 6‐OHDA‐induced Parkinsonism in ovariectomized rats
Authors: Medhi Bikash , Bansal Seema , Sharma Amit R. 
Published: May 2022

BackgroundEpidemiological studies have reported that the incidence of Parkinson’s disease (PD) is 1.5 times more in men as compared to women. It suggests that gonadal hormones influence the development and progression of PD. Estrogen replacement therapies have a protective effect against dopaminergic toxins and can be protective in Parkinsonism. However, there are multiple unresolved issues regarding the safety of ERT. Thus, there is a essential need to find alternatives that would avoid these health risks.ObjectivesThus main objective of study was to assess effect of 17α‐estradiol, a non‐feminizing estrogen, in attenuating PD employing an animal model of surgical menopause.Methodology17α‐estradiol and 17β‐estradiol was injected 10 µg/kg/s.c. for 14 days in ovariectomized 6‐OHDA rats. After 14 days of drug administration behavioral parameters of Parkinsonism (sensorimotor activity, motor coordination, and locomotor activity) were performed. These behavioral parameters were further correlated with various biochemical and molecular markers in postmenopausal Parkinsonism. Uterine weight and serum estradiol levels were also assessed to determine estrogenic effect of both the drugs peripherally. Effect of both drugs on expression of ER‐α and ER‐β in striatum was also evaluated. Further the differential effect of 17α‐estradiol and 17β‐estradiol was evaluated in postmenopausal Parkinsonism.Results17α‐estradiol and 17β‐estradiol equally modulated behavioral changes and attenuated rise in oxidative stress markers, inflammatory markers, improving neurotrophic factors and modulation of striatal neuron morphology. 17β‐estradiol treatment restored the uterine weight and serum estradiol levels towards normal, however 17α‐estradiol did not show any effect on uterine horns and serum estradiol levels. No effect of 17α‐estradiol was observed on expression of ER‐α and ER‐β in the striatum, indicates receptor independent effect of 17α‐estradiolConclusionBoth 17α‐estradiol and 17β‐estradiol are equally effective in Parkinsonism, however, 17α‐estradiol may prove to be safer alternative of 17β‐estradiol in Parkinsonism due to lack of feminizing effect.
Expression of Micrornas Mir‐126, Mir‐133b and Mir‐221 Associated With Apoptosis in Rats Submitted to Focal Cerebral Ischemia and Physical Exercise
Authors: Nunes Maria Julia , Figueiredo Rafael Z. , Tirapelli Vitor C. , e Silva Stevanato Ana Laura R. , Filho Sebastião de Campos Reis , Cirino Mucio Luiz d. A. , da Cunha Tirapelli Daniela P. , Tirapelli Luis Fernando 
Published: May 2022

INTRODUCTIONStroke is one of the main causes of death and disability in Brazil and worldwide. The great impact on the quality of life of the population and on the health system justifies that we seek relevant alternatives to reduce the incidence and improve the treatment and recovery of patients affected by this disease. Physical exercise appears as an important tool in this scenario, being already pointed out as a possible therapeutic approach for the prevention of non‐contagious chronic diseases. Studies have shown that physical exercise when used in a systematic and organized way produces positive effects on the individual's quality of life and health. In this context, biomarkers such as miRNAs that respond to physical exercise and are directly related to several epigenetic mechanisms appear. Therefore, explaining the molecular mechanisms involved during physical exercise will lead to a better understanding of each stimulus and the dose to be used to better respond to each situation, thus being a promising approach for the evolution of prescription and control of training and processes recovery from various diseases, including stroke.MATERIALS AND METHODSForty‐eight Wistar rats were used, divided into four experimental groups: control group, ischemia group, physical exercise group and exercise + ischemia group. Real‐time PCR methodology was used to analyze the expression of miRNAs: miR‐126, miR‐133b and miR‐221.RESULTS AND CONCLUSIONIn our study we observed significant difference in miR‐221 expression between the control group and the other groups. However, microRNAs: miR‐126 and miR‐133b do not show significant differences in expression between groups.
Effectiveness of X‐ray in Detecting the Fabella Sesamoid Bone
Authors: Alzahabi Obadah , Bauman Jay 
Published: May 2022

The highly variable prevalence of the fabella, a sesamoid bone located posterior to the lateral condyle of the femur, invites further investigation. A recent meta‐analysis by Berthaume [J. Anat. 2019 Jul; 235(1): 67‐79. doi:10.1111/joa.12994] reports that the incidence rate of the fabella has increased over the past 150 years. Within the data aggregated by that study, there is also a significant difference in detecting the fabella based on the method of detection ‐ anatomical dissection (28.9% prevalence, N = 5723 knees) vs. X‐ray (15.3% prevalence, N = 13665 knees). We sought to investigate whether variation in the density of fabellae could explain both changes in its prevalence over time as well as the discrepancy between methodologies.Our first aim was to directly compare the two methodologies, dissection and X‐ray, within the same set of knees on their determination of fabella prevalence. We hypothesized that fewer fabellae would be detected by X‐ray than dissection. Secondarily we are currently evaluating the hypothesis that some fabellae exist but are not sufficiently dense to be reliably detected via X‐ray.Fifty human knees were isolated by transverse sections through the middle of the upper and lower legs. The knees were obtained from cadavers received through the Saint Louis University Gift Body Program of the Center for Anatomical Science and Education (CASE) with signed, informed consent from the donor. The CASE Gift Body Program abides by all the rules set forth by the Uniform Anatomical Gift Act. An X‐ray generator (AJEX Meditech) emitted rays at 70 kV, 2.0 mAs through the medial or lateral side of each knee into a photo‐sensitive plate. Images from the plate were digitized using TigerView software. Three raters assessed whether a fabella was present in the X‐ray images (e.g. Fig. 1) using inter‐rater agreement, while one individual subsequently performed anatomical dissection.The prevalence rate via X‐ray was 12% (using a standard of 2/3 rater agreement). Fleiss’ kappa was 0.24 for X‐ray ratings, which represents a fair amount of interrater agreement. The prevalence rate based on anatomical dissection was 54%, which is significantly different from that of X‐ray (p < .0001, chi‐square statistic is 19.95).These results confirm that X‐ray imaging underreports the prevalence of fabellae. This is to our knowledge the first study that directly compares X‐ray against dissection within the same subjects for sesamoid identification, which is important for diagnosing conditions such as fabella syndrome on presentation of posterolateral knee pain. The authors continue to analyze the fabellae obtained from anatomical dissection to determine why some sesamoids are not consistently visible under X‐ray.
GRK2, a novel regulator of skeletal development
Authors: Yoshioka Natalie K. , Karuppagounder Vengadeshprabhu , Pinamont William J. , Deiter Gina M. , Elbarbary Reyad A. , Pacifici Maurizio , Kamal Fadia 
Published: May 2022

STUDY OBJECTIVEDuring skeletal development, the cartilaginous growth plate (GP) allows for bone elongation, composed of chondrocytes organized into three histological zones: resting (RZ), proliferative (PZ), and hypertrophic (HZ). Resting chondrocytes proliferate, become prehypertrophic, then hypertrophic, to create room for bone deposition. The G‐protein coupled receptor (GPCR) Parathyroid Hormone Receptor‐1 (PTH1R) expressed on the chondrocytes of the prehypertrophic zone, decelerates the transition to hypertrophy. PTH1R signaling is regulated by GPCR kinase 2 (GRK2); GRK2 phosphorylates PTH1R leading to its internalization and signal termination. Recent studies showed that loss of function mutations in GRK2 result in skeletal deformities, and we demonstrated that GRK2 promotes chondrocyte hypertrophy (CH) in adult arthritic cartilage. However, the role of GRK2 in molecular signaling in GP chondrocytes has yet to be explored.HYPOTHESISWe hypothesized that GRK2 desensitizes PTH1R to promote CH in the GP.METHODSWe utilized the Cre‐Lox system to generate transgenic mice with inducible ‐conditional‐knockout of GRK2 (GRK2‐icKO) in chondrocytes. KO was initiated at postnatal day 3 (PN3) by Tamoxifen ip injections and mice were sacrificed at PN10 to examine the effects on early and late stages of skeletal development. We performed H&E staining to analyze histological changes in GP structure. To determine changes in molecular signaling, we used ISH and IF staining to quantify expression of GRK2, PTH1R, BrdU (proliferation marker), and ColX (CH marker). At the chondro‐osseous junction, we quantified apoptosis (TUNEL staining), bone deposition (Col1 and Runx2 IF), and matrix mineralization (Alizarin Red (AR) staining). We used in vitro experiments with primary chondrocyte culture to confirm in vivoresults. GRK2 knockdown (KD) was achieved with siRNA before inducing CH. Gene and protein expression of the same molecular markers were analyzed with qPCR and WB, and matrix mineralization quantified by AR.RESULTSGKR2‐icKO mice had: (1) Shorter bones (2) Retained PTH1R expression in the HZ, with reduced gene expression (Fig. 1A), as confirmed in vitro (Fig. 1D) (3) Longer PZ and more proliferative chondrocytes confirmed by BrdU, (4) shorter HZ and less hypertrophic chondrocytes, confirmed by ColX IF (Fig. 1B). (5) At the chondro‐osseous junction, GRK2‐icKO mice had reduced chondrocyte apoptosis, bone deposition, and matrix mineralization (Fig. 1C). In vitroexperiments demonstrated increased GRK2 expression with CH, where GRK2 KD reduced CH and matrix mineralization (Fig. 1D).CONCLUSIONSWe show a novel role of GRK2 in skeletal development as a major regulator of PTH1R in GP chondrocytes. GRK2‐icKO increases chondrocyte proliferation and reduces hypertrophy and apoptosis, leading to reduced bone deposition, matrix mineralization, and shorter bones. Altogether, this presents GRK2 as a novel therapeutic target for skeletal abnormalities.
Identifying Critical DO2 with Compensatory Reserve during Simulated Hemorrhage in Humans
Authors: Convertino Victor A. 
Published: May 2022

BackgroundHemorrhage is a leading cause of potentially‐survivable death in trauma. The basic principle for treatment of ongoing bleeding prior to hemorrhage control is that early detection and intervention will improve outcome. However, current monitoring technologies that rely on standard vital signs are unreliable in assessing the clinical status of trauma patients because of variability in the capacity of individuals to compensate for hypovolemia. A monitoring capability designed to measure changes in systemic oxygen delivery (DO2) would provide an earlier indicator of clinical status in patients with life‐threatening blood loss. Maintaining DO2 above the level associated with the onset of shock (i.e., DO2crit) until bleeding is controlled should be the aim of any hemorrhage intervention. But DO2crit has not been identified in humans. Over the past decade, measuring the physiological phenomenon of compensatory reserve (CRM) based on interrogation of arterial waveform morphology has provided a capability to assess the reduction in the capacity to compensate for ongoing progressive central hypovolemia. Based on non‐human primate hemorrhage experiments, we hypothesized that humans would demonstrate a linear relationship between CRM and DO2, allowing for the identification of a DO2crit in humans of ~5 to 6 ml O2·kg‐1·min‐1. We also hypothesized that individuals with high (HT) and low (LT) tolerance to hypovolemia (i.e., ‘good’ versus ‘poor’ compensators) would have similar CRM‐DO2 relationships and DO2crit.Study Design and MethodsCRM and calculated DO2 were measured in 166 healthy subjects (97 males, 69 females) with a mean ± SD age of 23 ± 4 years, height of 171 ± 11 cm, and weight of 69 ± 11 kg. All subjects underwent progressive central hypovolemia induced by lower body negative pressure as a model of ongoing hemorrhage to a physiological state of hemodynamic decompensation. Subjects were classified as having either high tolerance (HT; N = 111) or low tolerance (LT; N = 55) to central hypovolemia based on whether they completed 5 minutes at ‐60 mmHg LBNP.ResultsHT and LT groups were matched for age, weight, BMI, and vital signs, DO2 and CRM at baseline. The CRM‐DO2 relationship was best fitted to a logarithmic model in HT subjects (R2 = 0.971) and a polynomial model in the LT group (R2 = 0.991). Average DO2crit for the entire subject cohort was estimated at 5.3 ml O2·Kg‐1·min‐1, but was ~14% lower in HT compared to LT subjects. The reduction in DO2 from 40% CRM to 20% CRM was 2‐fold greater in the LT compared to the HT group.ConclusionsAverage DO2crit in humans is 5.3 ml O2·Kg‐1·min‐1, but is ~14% lower in HT compared to LT subjects. The CRM‐DO2 relationship is curvilinear in humans, and different when comparing HT and LT individuals. A threshold for an emergent monitoring signal should be set to 40% CRM given that the decline in DO2 from 40% CRM to 20% CRM for LT subjects is located on the steepest part of the CRM‐DO2 relationship.