bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential contribution of brain‐region‐specific melanocortin 5 receptor to physical activity levels in lean vs. obesity‐prone rats
Authors: SHUKLA CHARU , KOCH LAUREN G , BRITTON STEVEN L , CAI MINYING , HRUBY VICTOR J , NOVAK COLLEEN M
Published: June 2021

The brain melanocortin (MC) system consists of peptides such as α‐MSH that act via MC receptors (MCR) to modulate energy balance. MC3R and MC4R are known to alter energy expenditure and food intake, but the role of MC5R in the brain remains poorly understood. We previously demonstrated that high‐activity rats bred for high‐aerobic capacity (HCR) show enhanced MC5R mRNA expression in the peri‐fornical lateral hypothalamus (PeFLH) compared to their low‐activity, low‐aerobic capacity counterparts (LCR). Here, we tested the hypothesis that hypothalamic MC5R expression is integral to the high‐activity phenotype. We measured physical activity (PA) after site‐directed microinjections in the PeFLH, using a specific agonist or antagonist of MC5R in a rat model of leanness vs. obesity (HCR and LCR). Intra‐PeFLH microinjections of the MC5R agonist significantly enhanced PA over a 3‐hour period, and this effect was greater in HCR relative to LCR. Moreoever, the MC5R antagonist significantly suppressed night‐time PA in lean HCR, but not obesity‐prone LCR. The MC5R agonist did not significantly alter food intake in either group. Taken together, these data implicate region‐specific MC5R in individual differences in PA; MC5R‐mediated PA may be a key trait distinguishing the lean phenotype. MC5R agonist was obtained from M. Bednarek (MedImmune Ltd, Cambridge, UK). Research support was from NIH R01NS055859 to CMN and AHA 11PRE7320029 to CS.
Neuronostatin alters gene expression in rat anterior pituitary cells: a possible role in energy balance and glucose homeostasis
Authors: Redlinger Lauren J. , Yosten Gina L.C. , Samson Willis K.
Published: June 2021

Neuronostatin is a recently discovered peptide hormone derived from the somatostain preprohormone (JBC 287:4572, 2008). We now have identified that the orphan G protein‐coupled receptor, GPR107, is a potential cognate receptor for neuronostatin (AJP 303:R941, 2012). Because of the abundant expression of GPR107 in anterior pituitary cells, and because neuronostatin is present in somatostatin‐producing neurons of the hypothalamus that project to median eminence, we hypothesized that neuronostatin would alter hormone production in anterior pituitary. The ability of neuronostatin to activate early gene expression in pituitary gland further suggested trophic effects; however, we were initially unable to detect acute effects of the peptide on basal, stimulated or inhibited hormone secretion in cells in culture. Therefore, anterior pituitary cells were isolated from male rats, treated for longer time periods with neuronostatin, and changes in hormone gene expression were examined using real‐time polymerase chain reaction. We found that neuronostatin activated early gene expression and induced an increase in growth hormone mRNA levels, suggesting that neuronostatin may regulate growth hormone production, which could have important implications for energy homeostasis and glucose metabolism in addition to possible direct effects in the pancreas where the peptide also activates early gene expression. (NIH HL066023)
Hibernation alters mucosa‐associated bacterial communities and mucin expression in 13‐lined ground squirrels
Authors: Sommer Katie , Zeng Austin , Dill‐Mcfarland Kimberly A. , Suen Garret , Carey Hannah V.
Published: June 2021

Hibernating mammals cease food intake during winter, which eliminates dietary substrates that support growth of gut microbes. We showed recently that cecal content microbiota undergoes seasonal restructuring in hibernators that is likely due to effects of extreme fasting on microbial communities. Here we asked whether the mucosa‐associated microbiota (MAM) is altered by the annual hibernation cycle. We also measured goblet cell numbers and expression of the mucin glycoprotein MUC2. Pyrosequencing of 16S rRNA from bacterial DNA extracted from cecal tissues revealed that compared to summer (SUM) squirrels, relative abundance of the phyla Bacteroidetes and Proteobacteria increased, whereas Firmicutes were reduced in early (EW) and late (LW) winter squirrels. Abundance of Verrucomicrobia, which contains the dedicated mucin degrader Akkermansia, was highest in LW. MUC2 expression was greater in EW and Spring squirrels relative to SUM and LW, and the number of goblet cells/crypt length was highest in EW. The results indicated that MAM is altered by the hibernation cycle, as is production of mucin, one of the primary substrates for microbial degradation during winter fasting. Supported by UW‐SVM Summer Scholars and discretionary funds (KS, HVC).
Lycium Barbarum Polysaccharides Mitigate Chronic Intermittent Hypoxia Induced Hippocampal Oxidative Stress, Inflammation And Apoptosis In Rats
Authors: Lam Chun Sing , Tipoe G.L. , Fung M.L.
Published: June 2021

Chronic intermittent hypoxia (CIH) induces oxidative stress, inflammation and apoptosis in hippocampus. Lycium barbarum polysaccharides (LBP), bioactive ingredients of traditional Chinese herbal medicine Goji, were proposed to possess anti‐oxidative and anti‐inflammatory properties. Our study aims to investigate the neuroprotective effect of LBP in CIH rats. We hypothesize that LBP ameliorate oxidative stress, inflammation and apoptosis in the hippocampus of rats exposed to CIH. Malondialdehyde (MDA) assay was used to measure the lipid peroxidation extent. Western blot was employed to examine the expressions level of antioxidant enzymes (SOD‐1, SOD‐2); inflammatory mediators (IL‐1β, TNFα, COX‐2); caspase‐dependent extrinsic (FADD, cleaved caspase 8, Bid) and intrinsic apoptotic (Bax, Bcl2, cytochrome C) cell death (cleaved caspase 3) cascades. In situ cell death staining (TUNEL) was utilized to reveal the apoptotic status of hippocampal subfields (DG, CA1 and CA3). LBP administrations remarkably attenuated oxidative stress, inflammation and apoptosis in hypoxic group. In addition, LBP significantly mitigated caspase‐dependent apoptotic extrinsic and intrinsic cascades in hypoxic group. To conclude, LBP are neuroprotective against CIH‐induced hippocampal injuries. Studies supported by RGC research grants (HKU 7510/06M, HKU 766110M) and HKU funding (201007176007, SFPBR 200911159072).
Long‐lasting increase in basal catecholamine secretion from neonatal adrenal medullary chromaffin cells by chronic intermittent hypoxia
Authors: Makarenko Vladislav V , Kumar Ganesh K , Prabhakar Nanduri R
Published: June 2021

We previously reported that intermittent hypoxia (IH) facilitates hypoxia‐evoked catecholamine (CA) secretion from neonatal adrenal medullary chromaffin cells (AMC) in rat pups. Here, we examined the effects of repetitive hypoxia on CA secretion from AMC from IH exposed rat pups. Adrenal medullary slices were harvested from rat pups exposed to either IH or normoxia from ages P0‐P5, 8–9 hours/day. CA secretion was monitored by carbon fiber amperometry. In IH exposed pups, repetitive hypoxia (30s hypoxia followed by 90s normoxia × 5 episodes) facilitated CA secretion from AMC during each episode. Remarkably, basal CA secretion remained elevated for 30 min after terminating repetitive hypoxia. The long‐lasting increase in basal CA secretion was not seen in response to repetitive application of 40 mM K+. In striking contrast, in control pups, CA secretion during repetitive hypoxia was modest and after terminating the stimulus, promptly returned to basal levels. The long‐lasting increase in basal CA secretion in IH pups could be elicited in Ca2+ free medium and was prevented in presence of 10 μM ryanadine, which blocks ryanadine receptors (RyRs). These data suggest that neonatal IH results in long‐lasting activation of basal CA secretion by repetitive hypoxia, and this effect is mediated in part by RyRs and mobilization of intracellular Ca2+ (supported by HL‐90554, HL‐76537, HL‐86493 and HL‐089616).
Muscular Remodeling by Melatonin with and without Therapeutic Exercise in Collagenase‐induced Osteoarthritic Rats
Authors: Kim Joo‐Heon , Hong Yunkyung , Lee Seunghoon , Hong Yonggeun
Published: June 2021

Osteoarthritis (OA) is characterized by progressive degeneration of arthritic cartilage, subsequent joint narrowing, and abnormal gait. The purpose of this study was to determine the effects of melatonin with and without exercise on muscle remodeling and functional gait in collagenase‐induced OA rats. A melatonin (MT) injection was given subcutaneously twice/day. Treadmill exercise (Ex) was conducted for 1 h/day at a frequency of 5 days/week. Body weight was significantly reduced by MT with and without exercise (P < .05), whereas no significant change was observed in the gastrocnemius or tibialis anterior muscle mass in the OA+MT or OA+MT+Ex groups at day 28. MAFbx, a ubiquitin E3 ligase, was increased in the medial gastrocnemius in OA+MT+Ex rats at day 7 (P < .05). Intervention also caused upregulation of autophagic molecules LC3 and BECN1 (P < .05). At day 28, the relative distribution of MHC1¥â was significantly increased in the gastrocnemius of OA+MT and OA+MT+Ex groups (P < .05). Sarcomeric nebulin was also increased by MT with and without Ex at day 28 (P < .05). Footprint analysis showed that intervention increased the feet contact area, recovering functional gait. The results indicate that muscle remodeling by intervention recovered functional gait in collagenase‐induced OA in rats.
Bone Mineral Density and Regular Swimming: Observational and Interventional Studies
Authors: Alkatan Mohammed , Nualnim Nantinee , Tyson Kim , Tanaka Hirofumi
Published: June 2021

Although exercise in general is beneficial for enhancing bone mineral density (BMD), people who participate in non‐weight bearing, low impact, activities are at a greater risk for bone loss. A recent study indicates that excessive dermal calcium loss through sweat will create bone demineralization and decrease bone mineral density in some athletes. Swimming exercise is characterized by low impact activity but sweat loss is much smaller than other endurance‐trained athletes. First, using the cross‐sectional study, BMD was measured using dual‐energy x‐ray absorptiometry in 44 sedentary controls (56±1 years), 48 runners (54±1 years), and 27 swimmers (57±1 years). Body mass and body fatness were significantly lower in runners than in swimmers and sedentary controls. Total (whole‐body) BMD was not different among the groups. Runners had significantly higher leg BMD than swimmers and sedentary controls (1.38±0.02 vs. 1.33±0.04 and 1.32±0.02 g/m2). There were no differences in other regional (head, arms, trunk, ribs, pelvis and spine) BMD between the three groups. We then determined changes in BMD after 3 months of swimming exercise intervention in 24 previously sedentary adults (58±2 years). Total and regional BMD did not change. Collectively, our observational and interventional findings indicate that swimming exercise is not associated with a greater bone mineral density.
METTL21C: From GWAS to in vitro function in skeletal muscle cells
Authors: Huang Jian , Hsu Yi‐Hsiang , Mo Chenglin , Abreu Eduardo , Karasik David , Brotto Marco
Published: June 2021

Sarcopenia and osteoporosis are among the most serious and costly public health problems and often occur concurrently. Bivariate genome‐wide association studies (GWAS) identified METTL21C as a candidate gene for bone‐muscle pleotropy. Intriguingly, METTL21C is highly expressed in skeletal muscles, but the roles of this gene are largely unknown. We used siRNAs to silence METTL21C in C2C12 myoblasts to study its function on myogenesis. After 24h of transfection, real‐time PCR revealed that METTL21C expression was reduced by 30–40% in the siRNA‐treated cells. Two days after the onset of differentiation, a significantly reduced number of fusing myocytes was observed. At day 4, early myotubes were clearly observed in the control group but not in the siRNA‐treated cells. By day 7, fully matured and developed myotubes were observed in the control but not in the siRNA‐treated cells. Silencing of this relatively unknown gene led to a striking phenotype of fewer, shorter and smaller myotubes. These results suggest that METTL21C plays an important role in skeletal muscle cell differentiation. We are now performing similar studies in MLO‐Y4 osteocytes and plan to expand these studies to include biochemical and functional analyses to determine and validate its pleiotropic effects in in‐vitro models of bone and muscle research. Support: NIH‐NIA P01 AG039355 and Missouri Life Sci. Res. Board (MB) and R01 AR057118 (DK)
Phosphodiesterase 5 inhibition rescues functional sympatholysis in Duchenne Muscular Dystrophy
Authors: Nelson Michael , Martin Elizabeth A. , Tang Xiu , Johannes Jimmy , Lewis Joshua , Gurudevan Swaminatha V. , Nelson Stanley , Miceli Carrie , Victor Ronald G.
Published: June 2021

We recently reported that functional sympatholysis (i.e., muscle contraction‐induced attenuation of reflex vasoconstriction) is impaired in Becker Muscular dystrophy and rescued by phosphodiesterase (PDE)5 inhibition with tadalafil. However, tadalafil failed to rescue sympatholysis in one BMD patient with a rapidly progressive disease resembling Duchenne Muscular Dystrophy. Thus, we tested the ability of two different phosphodiesterase inhibitors, tadalafil and sildenafil, to rescue sympatholysis in DMD. In 6 boys with DMD (ages 7–13) and 8 healthy controls, we measured reflex vasoconstriction (decreased forearm muscle oxygenation [ΔHb02, near infrared spectroscopy] evoked by lower body negative pressure) at rest and during rhythmic handgrip exercise. First, we confirm that sympatholysis is impaired in DMD, because handgrip greatly attenuated vasoconstriction in controls (ΔHb02: −22±6 vs. −9±5 %, p<.05; rest vs. HG) but caused no attenuation in DMD (−17±2 vs. −15±3%). Then, in a randomized single dose (0.5 mg/kg) cross‐over trial of tadalafil vs. sildenafil, we show that sympatholysis is rescued in DMD by either PDE5 inhibitor (tadalafil: −21±3 vs. −11±4; sildenafil, −22±4 vs. −12±3%; ΔHb02 rest vs. HG). PDE5 inhibition therefore constitutes a putative therapeutic treatment option for patients with either Becker or Duchenne Muscular Dystrophy.

Support: Parent Project Muscular Dystrophy
Vasopressin V1a receptor and voluntary locomotion linked with cerebral activation in free‐moving mice
Authors: Masuki Shizue , Sumiyoshi Eri , Koshimizu Taka‐aki , Tsujimoto Gozoh , Nose Hiroshi
Published: June 2021

We have reported that cerebral activation suppressed baroreflex control of heart rate (BR), followed by voluntary locomotion (VL) at higher probability. We examined if vasopressin V1a receptor (V1aR) in the brain was involved in the responses using free‐moving V1aR knockout (KO, n=8), wild type infused with V1aR blockade into the nucleus tractus solitarii (BLK, n=8), and control mice (CNT, n=8). Sensitivity of BR was determined from spontaneous changes in heart rate and mean arterial pressure (ΔHR/ΔMAP) every 4 s during a total resting period for ~8.8 h of 12 daytime hrs. ΔHR/ΔMAP was adopted in periods where cross‐correlation function (R(t)) between ΔHR and ΔMAP was significant (P<0.05). Cerebral activity was determined from the power density ratio of θ to δ wave band (θ/δ) on EEG every 4 s. We found that spontaneous change in θ/δ was significantly correlated with R(t) during 62±3% of the total resting period in CNT (P<0.05), while only 38±4% in KO and 47±2% in BLK (vs CNT, both P<0.001). When R(t) and ΔHR/ΔMAP were divided into 6 bins according to θ/δ, both were positively correlated with θ/δ in CNT (both P<0.001), while neither was correlated in KO or BLK (all P>;0.05). Moreover, the probability of VL after an increase in θ/δ was 24±4% in KO and 24±6% in BLK, lower than 61±5% in CNT (P<0.001), with no suppression of BR. Thus, central V1aR plays an important role in starting VL after cerebral activation through suppression of BR.
Purinergic receptor antagonism does not attenuate the exercise pressor reflex in hypertensive adults
Authors: Greaney Jody L , Boggs Mary E , Matthews Evan L , Edwards David G , Farquhar William B
Published: June 2021

A previous study reported that purinergic (P2) receptor antagonism attenuated the blood pressure (BP) response to static handgrip (HG) in healthy adults. The aim of this study was to determine if pyridoxine HCl is an effective in vitro P2 receptor antagonist and if localized P2 receptor antagonism with pyridoxine in vivo blunts the exaggerated exercise pressor reflex (EPR) in older hypertensive (HTN) adults. For in vitro studies, dorsal root ganglion (DRG) cells isolated from mice were loaded with fura 2‐AM and incubated in control buffer (HBSS) or 100μM pyridoxine. Following incubation, the effect of 10μM ATP on intracellular Ca2+ was measured. The Ca2+ response was attenuated in DRG cells incubated with pyridoxine (HBSS: Δ130±10 nM v pyridoxine: Δ13±2 nM; P<0.05). For in vivo studies, 8 HTN adults (6M; 67±1 yrs; BP 141±5/81±4 mmHg) completed a control (0.9% saline; NS) and P2 receptor blockade (730mM pyridoxine) trial (randomized; 1 month apart). BP (Finometer) was measured at baseline and during static HG at 40% maximal voluntary contraction followed by post‐exercise ischemia (PEI). P2 receptor blockade did not blunt the increases in mean BP during HG (NS: Δ21±4 v P2: Δ23±5 mmHg; P>;0.05) or PEI (NS: Δ15±3 v P2: Δ17±3 mmHg; P>;0.05). These preliminary data suggest that pyridoxine is an effective in vitro P2 receptor antagonist but indicate that in vivo P2 receptor antagonism does not attenuate the EPR in older HTN adults.

Supported by AHA 11PRE7580029 and ACSM Foundation.
EGF suppresses intestinal epithelial cell shedding both in vitro and in vivo via a MEK/ERK dependent pathway
Authors: Frey Mark R , Miguel Jennifer C , Lien Ching‐Ling , Watson Alastair J
Published: June 2021

Epithelial cell shedding from the intestinal villus is a key element of normal tissue turnover. Increased cell shedding is associated with inflammatory bowel diseases. The signals regulating this process are not well understood. In this study, we asked whether shedding is controlled by epidermal growth factor (EGF) receptor, an important driver of intestinal growth and differentiation.

METHODS

Cell extrusion events in vivo (zebrafish midgut) or in vitro (MDCK or IEC‐6 cells) were identified by rhodamine‐phalloidin labeling of condensed actin rings. In vitro, shedding rates were assessed by counting extruded cells in the culture media over time. EGF, with or without MEK inhibitor (U0126), was given by intraperitoneal injection (fish) or in culture media (cells).

RESULTS

EGF reduced detectable shedding events on zebrafish villi (34% decrease, p<0.05) and from MDCK (49% decrease, p<0.01) or IEC‐6 (42% decrease, p<0.01) cell monolayers. Pharmacological blockade of MEK/ERK reversed these effects both in vitro and in vivo. In contrast, inhibitors to other EGF‐stimulated pathways such as PI3K/Akt or PKC had no effect.

CONCLUSIONS

EGF receptor suppresses cell shedding in the intestinal epithelium through a specific MEK/ERK dependent pathway. These results may open the door to new therapeutic avenues for targeting excessive cell turnover in conditions such as inflammatory bowel diseases.
Indian Hedgehog mediates gastrin‐induced proliferation in the adult stomach
Authors: Feng Rui , Aihara Eitaro , Kenny Susan , Yang Li , Varro Andrea , Samuelson Linda , Montrose Marshall , Zavros Yana
Published: June 2021

Loss of parietal cell‐expressed Sonic Hedgehog (Shh) results in hypergastrinemia accompanined by increased expression of Indian Hedgehog (Ihh) and hyperproliferation of the surface pit cells. Suppressing hypergastrinemia reverses the observations. Whether hypergastrinemia‐induced surface pit cell hyperproliferation is mediated by Ihh is unknown. Here we test the hypothesis that gastrin induces gastric epithelial proliferation via activation of Ihh signaling. Hypergastrinemic mice expressing a parietal cell‐specific deletion of Shh (PC‐ShhKO) crossed with gastrin‐deficient (GKO) mice (PC‐ShhKO/GKO) were used. To identify the Ihh signaling transduction, epithelial and mesenchymal layers of stomachs collected from gastrin‐infused PC‐ShhKO/GKO mice were seperated. Gastric 3D organoids transfected with lentiviurus targeting Ihh and Gli1 were used. Compared to PC‐ShhKO/GKO mice, hypergastrinemic PC‐ShhKO mice and gastrin infused GKO had a significantly higher proliferation and Ihh expression. Gastrin‐induced Ihh expression was prodominantly within the epithelium and expression of Gli1 was restricted to the mesenchyme. Knockdown of Ihh or Gli1 in mouse gastric 3D organoids caused a significant reduction of gastrin‐induced proliferation. In conclusion, Ihh signaling mediates gastrin‐induced epithelial cell proliferation in the adult stomach. Funding: NIH 1R01DK083402 (Y. Zavros).
Chronic delta‐9‐tetrahydrocannabinol differentially regulates gene expression in duodenum of Simian immunodeficiency virus‐infected macaques
Authors: Voloshenyuk Tetyana , LeCapitaine Nicole , Zabaleta Jovanny , Amedee Angela , Robichaux Jared , Walker Morgan , Molina Patricia
Published: June 2021

Previously we demonstrated that chronic Δ9‐tetrahydrocannabinol (THC) administration attenuates classic markers of simian immunodeficiency virus (SIV) disease progression, decreases early mortality and attenuates inflammation in SIV‐infected rhesus macaques. The mechanisms involved in amelioration of disease progression are unknown. The gut is an important target for HIV/SIV infection. We hypothesized that modulation of genes involved in mucosal immunity, viral replication and barrier function may contribute to THC‐modulated disease progression. We examined the impact of chronic THC administration on the duodenal transcriptome. Using GeneGO, duodenal gene expression of vehicle‐ or THC‐administered SIV‐infected (THC/SIV) macaques was compared to uninfected naive macaques. Analysis of the 188 genes differentially regulated by THC using STRING database identified their role in antiviral and stress responses and gut barrier and immune function. THC/SIV gene expression ≥ 1.5‐fold or ≤ 0.5‐fold was verified by RT‐qPCR and Western blot. THC significantly increased mRNA expression of antiviral MX‐1, protein expression of IFIT1 and HSPA2 and attenuated the increase of IGJ protein. These results suggest that THC‐mediated changes in gut gene expression may contribute to functional modification of gut immunity and participate in modulation of disease progression. Supported by DA020419, DA030053
Effects of IL‐6 on intestinal damage and cytokine profiles during recovery from heat stroke
Authors: Phillips Neil Andre , Richards Jennifer , Clanton Thomas
Published: June 2021

Interleukin‐6 is expressed at high levels during and after heat stroke. Previous studies have shown that IL‐6 deficient mice are intolerant of heat. The mechanisms for the apparent protective effects of IL‐6 are unknown. We hypothesized that IL‐6 reduces the severity of the pro‐inflammatory cytokine response and intestinal damage associated with heat stroke. Circulating cytokines and small intestine (SI) histology were evaluated in anesthetized mice 30 and 120 min following a progressive heat treatment to 42.4°C. Thirty min following HS, IL‐6, KC, IL‐10, MCP‐1, IL‐12, IP‐10, TNF‐α, IP‐10, and MIP‐1α were significantly elevated (P<0.05). All remained elevated at 2h, except TNF‐α and MIP‐1α. Pre‐treatment with IL‐6 failed to alter the circulating cytokine profile. HS induced marked injury to the proximal SI (duodenum) at 30 min (P<0.05), but at 2h into recovery, injury levels resembled those of control sham animals. IL‐6 pre‐treatment significantly attenuated the heat‐induced increases in injury and villus width (swelling) seen in the proximal SI (P<0.05), 30 min into recovery. No differences were seen at 120 min. We conclude: IL‐6 pre‐treatment is effective in protecting the proximal SI. The mechanism for protection does not appear to involve attenuation of the circulating inflammatory cytokine response. AHA #11GRNT7990119
Zonula occludens (ZO)‐1 is required for epithelial morphogenesis and lumen development
Authors: Odenwald Matthew , Joseph Nora E. , Fanning Alan S. , Turner Jerrold R.
Published: June 2021

Epithelial morphogenesis involves establishment of cell polarity and formation of the tight and adherens junctions between adjacent cells. However, contributions of tight junctions to epithelial morphogenesis remain poorly understood. Studies of epithelia lacking the scaffold‐like tight junction protein ZO‐1 in 2D culture have identified reduced barrier function with few other defects, likely due to overlapping functions of ZO‐2. To address the role of ZO‐1 in 3D morphogenesis, we compared growth of control and ZO‐1 knockdown (kd) MDCK cells in 3D collagen gels. Over 90% of cysts formed by shRNA control MDCK displayed a single lumen phenotype, while >;90% of ZO‐1 kd cysts had multiple lumina. Consistent with the increased cellular mass required, ZO‐1 kd MDCK displayed increased proliferation (apoptosis was similar to controls). The multi‐lumen phenotype was not due to aberrant cellular polarization, as claudin‐2 (tight junction), E‐cadherin (adherens junction and basolateral membrane), and gp135 (apical membrane) were normally distributed in ZO‐1 kd cysts. Expression of ZO‐1 SH3‐GuK or ABR (actin binding region) domains as free proteins in wildtype MDCK resulted in multi‐lumen cysts similar to ZO‐1 kd. These data suggest that both SH3‐ GuK‐ and ABR‐mediated interactions are essential for morphogenesis of epithelial lumina via mechanisms that do not involve cell polarity and cannot be complemented by ZO‐2.
Comprehensive Scanning Cysteine Mutagenesis Reveals Claudin‐2 Pore Lining Residues with Distinct Properties
Authors: Li Jiahua , Zhuo Min , Pei Lei , Yu Alan S.L.
Published: June 2021

Claudins are tight junction proteins that determine paracellular permeability in epithelia. The first extracellular loop of claudin‐2 forms a paracellular cation pore. To understand the structure and function of this pore, we aim to conduct a comprehensive cysteine‐scanning mutagenesis of the first extracellular loop and map out the amino acids that line the pore. We screened 45 cysteine mutants of the first extracelllular loop in polyclonal MDCK II Tet‐ Off cells, and identified 9 mutants showed significant increase of TER after treating with the thiol‐reactive reagent, 2‐ (trimethylammonium) ethyl methanethiosulfonate (MTSET), suggesting they may line up the pore. Next, we expressed these 9 mutants in stably transfected monoclonal MDCK I Tet‐Off cells for confirmatory studies. While 8 out of the 9 mutants have similar cation pore properties as the claudin‐2 wild type in cation selectivity, ions permeability, and pore size, they reveal distinct characteristics in MTS accessibility, reflecting their distinct geometric location within the pore. In conclusion, we identified eight residues lining up the claudin‐2 pore lumen with distinct MTS accessibility. This comprehensive map of the claudin pore region provides insights for studying the mechanism of paracellular ions and water transport. Supported by NIH grants R01DK062283, R01DK062283–07S1 and U01GM094627.
AN ENLARGED ANATOMICAL MODEL OF THE EYE IN PAPIER MACHE BY THE DOCTOR AUZOUX
Authors: Le Floch‐Prigent Patrice
Published: June 2021

An enlarged, anatomical model of eye in papier‐mâché belonged to the scientific bookstore GILLOT‐BRIEUX (48 rue Jacob, PARIS 6ème). The model measured 40×40×30 cm. It represented the adult, human eye in two halves separated by an horizontal plane, in order to expone the internal structures with the transparent components which were removable. The vascular rendering was very detailed. The orbital cavity was represented only in its inferior half. The muscles of the orbit and the arteries were represented and also the infra‐orbital and nasal parts of the adjacent face. This model was one of the very first in the production of Doctor AUZOUX (19th century) in its village of Saint Aubin d'Escroville in Normandy (LEMIRE, 1990). It was recently reproduced by its successors. The anatomical models of AUZOUX were very accurate and could be compared during the 19th century, only with composite models of TRAMOND.
Correlation of Student Performance on Team Based Learning (TBL) with Exams in Systems Based First Year Medical School Courses
Authors: Guttmann Geoffrey D. , Rosales Armando
Published: June 2021

TCOM Basic Sciences curriculum uses a two‐pass systems based approach. Students are introduced to normal anatomy, physiology, and biochemistry in the first year and then progress through an introduction to immunology and microbiology, pathology and pharmacology. As course directors, we implemented TBL in the Musculoskeletal System 1 and Nervous System 1 courses as a substitute for the pre‐exam reviews. The TBLs carried points towards the final course grade. Lecturers submitted questions that were mainly in the USMLE or COMLEX format, i.e. the question was based on a clinical vignette and the stem asked the students to determine which anatomical structure, mechanism or process was involved. A total of 20 questions were presented initially as an individual quiz and then they were repeated as a group quiz. For the group quiz, students went into their groups and then discussed each question whereupon a group leader would submit an answer based on a consensus of their knowledge. We are correlating student performance on the individual quiz and total TBL score with exam scores to determine the effectiveness of using TBL. We are also presenting a survey to determine student enthusiasm for the TBL process.
The pyramidal lobe: Connecting a case study with lymphatic system topics in gross anatomical education
Authors: Cassidy Keely
Published: June 2021

The pyramidal lobe is a variably present structure extending superiorly from the midline of the thyroid gland. A remnant of the thyroglossal duct, the pyramidal lobe may harbor precricoid (also known as Delphian) lymph nodes, which receive lymphatic drainage predominantly from the larynx, pyriform sinus, and thyroid gland. The grossly visible presence of precricoid lymph nodes can serve as an indication of metastasis of head and neck cancers. A sixty‐one year old male donor present in a human anatomy course displayed a shockingly pronounced pyramidal lobe, measuring nine centimeters in length. This individual also displayed several small swellings in the center of the pyramidal lobe where the precricoid lymph nodes frequently rest. This donor's cause of death was metastatic salivary gland carcinoma, and therefore involvement of the precricoid lymph nodes is an intriguing possibility. This case highlights the importance of the lymphatic system in gross anatomical education. Unfortunately, the lymphatic system may not be examined extensively in gross anatomy laboratory settings in part due to reduction in course hours and this system's relative inconspicuousness and fragility in dissection. However, this case study brings to light the clinical importance of seemingly insignificant segments of the lymphatic system as well as the necessity of comprehensive gross anatomical education on this topic.

Grant Funding Source: none
An Interprofessional Learning Module on Bone Marrow Biopsy within the Preclinical Undergraduate Medical Curriculum
Authors: Poznanski Ann , McGranahan Robert , Eastwood Jennifer , Venuti Judith
Published: June 2021

We have developed a module in which 2nd year medical students are taught about bone marrow biopsies. In this activity, integration of pelvic anatomy and bone marrow pathology is provided in the context of a clinical procedure on cadaveric specimens. The activity is guided and coordinated by a physician assistant from a bone marrow transplant service, an anatomist, a histologist and a pathologist from a basic science department. Demonstration of the bone marrow biopsy procedure on cadavers is preceded by student viewing of an online video of the technique and an orientation to pelvic anatomy and is followed by evaluation of microscopic images of normal and pathological bone marrow biopsy specimens. This integrated contextual interprofessional activity benefits both students and faculty through: increased motivation and satisfaction; enhanced self‐appraisal and self‐efficacy; professional socialization; and enhanced reflection by health professionals on preparing students for deliberatively working together with the common goal of creating a safer and better patient‐centered and community‐oriented health care system. Effectiveness of the interprofessional activity will be evaluated in 3 ways: 1) an end of year student focus group; 2) a student satisfaction survey; and 3) long‐term longitudinal evaluation of student course and board performance.
Development of a virtual 3D renal corpuscle for educational environments
Authors: Roth Jeremy , Wilson Timothy , Sandig Martin
Published: June 2021

Histology is a challenging educational discipline. It requires studying 2‐dimensional (2D) microscopic sections of tissue and inferring three‐dimensional (3D) organization. Gross anatomical education has benefitted from the burgeoning use of 3D models and images, however, 3D digital models of histological structures have not been developed for educational purposes. To overcome these limitations we have developed a 3D histological model of a renal corpuscle (RC) based on serial histological sections for e‐learning environments. Sprague Dawley rat kidneys were fixed, dehydrated, and embedded in epoxy resin (Embed‐812). Ribbons of serial semi‐thin sections (1μm thick) were obtained using a diamond knife and ultramicrotome. The sections containing the RC (n=179) were digitized and the images were aligned with the 3D visualization software, Amira 5.2, for 3D model development. Key structures of the RC and surrounding tissue were digitally reconstructed via manual segmentation. The resulting digital model allows for the generation of RC images in any plane with resolutions comparable to that of the original images. Users may view digitally generated histological sections in the context of the 3D renal corpuscle, enabling user interactivity and visualization in a variety of 2D or 3D orientations. Future plans for the model include developing an e‐learning module and subjecting it to usability tests.

Grant Funding Source: Instructional Innovation and Development Fund (IIDF)
Interactive Educational Touch Screen Panels In Anatomy Laboratuary Training
Authors: Yazar Fatih , Develi Sedat , Yalcin Bulent
Published: June 2021

Purpose

Today virtual computer‐aided programs have been widely used in methods of diagnosis and treatment. Providing new training materials to educational environment and using newly developed computer‐assisted medical applications have become a necessity.

Methods

In anatomy dissection laboratory for each small workgroups; mobile modules which have a high tech computer and 47′ touch screen with battery support established. Screen can be easily moved from vertical to horizontal or up and down. Many anatomic programs and images loaded to this system and online and wirelesss access to web sites and programs has been provided.

Results

In anatomy training, interactive educational applications, virtual cadavers, animations, videos and other visual materials have been used effectively by students and lecturers and will make learning easier and more attractive.

Conclusion

The touch screen virtual education panels, will facilitate the learning of students. Besides being a educational material in the dissection hall for students and lecturers, these panels will make easy to learn and understand anatomic structures by presenting virtual cadavers, animations, radiological images, atlases at the same time also will provide easy adaptation for recently developed medical products.
Teaching secular trends of human anatomy in a novel medical school module
Authors: Rühli Frank , Saniotis Arthur , Henneberg Maciej
Published: June 2021

Human anatomical structures show a wide range of variability. Also, secular trends of human anatomy (and pathology) have been frequently reported and are of foremost interest (e.g. for surgeons). However, the variability of human morphology is often neglected in traditional medical curricula. Recently, we presented our novel full semester medical school course on Evolutionary Medicine at the University of Adelaide. This elective course addressed the degree and impact of such secular trends. Evolutionary Medicine which addressees specifically the ongoing interactions of humans and the environment such as pathogens and climate, is a field of research and teaching of growing interest. Based on our own original data of recent temporal changes in human body structures – e.g. the prevalence of additional arteries or of spina bifida occulta ‐ such topics were addressed both in a classical lecture format, as well as, part of interactive seminars run by students. Students evaluated this course highly (median response 6 out of possible 7). Thus it is planned to also teach this course at other Medical Schools. Teaching secular trends of human anatomy is not only an important part of the novel field of Evolutionary Medicine but of upmost importance for the understanding of the human body for both, medical students and clinicians.

Grant Funding Source: N/A
Team‐based learning (TBL) in histology: lessons learned through 7 years of experience
Authors: Brokaw James Joseph , Condon Keith Warren
Published: June 2021

In 2006, we began the transition from a traditional lecture‐based histology course to a TBL course, gradually adding more TBL exercises each year until the course was virtually lecture‐free. Our laboratory sessions using microscopes and glass slides remained unchanged. We have previously reported that TBL produces learning outcomes comparable to those of lectures (Clin. Anat. 23: 474, 2010). Based on our trail‐and‐error experiences of the last 7 years, we now offer 4 key suggestions for successfully implementing TBL in histology: (1) Schedule the laboratory session before the corresponding TBL exercise. This permits the use of histologic images that students already have some familiarity with. (2) Limit Internet access during the TBL exercise, especially for clinically‐oriented problems. Students can quickly find the “right” answer via search engines without understanding why it is correct. (3) When discussing the TBL exercise in class, call out the names of individual students to respond using a checklist of the team rosters. This sends a clear message that all team members must fully participate in the process and be prepared to explain and defend the team's answers. (4) At the conclusion of the TBL exercise, provide a “take‐home message” about what the students are expected to understand about the topic. Students often fail to connect what they see in lab or read in the text with the problems presented in the exercise.
The integration of anatomy and radiology through interactive online modules
Authors: Krebs Claudia , Fejtek Monika , Hu Jeff , Kazem May , Lam Adriel , Liang Teresa , Zhang Tina , Hayward Sean , Nicolaou Savvas
Published: June 2021

Medical undergraduate programs require anatomy to be taught in a clinically relevant context. One natural fit for anatomy teaching is to integrate it with radiology. For this purpose anatomists and radiologists at UBC developed an integrated modular course that is tightly correlated with the anatomy curriculum, incorporating applicable anatomical structures with clinical radiology. We have created interactive modules and quizzes that correlate radiological anatomy to the relevant gross anatomy, and provide basic clinical applications. The regions covered include: spine, shoulder and elbow, thorax, abdomen, pelvis and head. Students are encouraged to participate interactively with mix and match, fill in the blank, and labeling activities. Feedback from the students allows faculty to assess which areas of the current integration process are less effectual and demonstrate avenues for potential improvement to the curriculum. Currently this project is focused on the first year of the UBC curriculum, but the format lends itself to expansion across all four years as well as continuing integration through the postgraduate years. Future anatomy teaching will likely move away from dedicated blocks of time and towards an approach integrated with clinical disciplines. Integration with the radiology program demonstrates the effectiveness of comprehensive anatomy teaching as it relates to a clinical discipline.

Grant Funding Source: N/A
Developmental horizons in the 2–4 month old infant aerodigestive tract
Authors: Micham Brittni Mae , Laitman Jeffrey T.
Published: June 2021

The human aerodigestive tract (ADT) is the crossroads of breathing, swallowing, olfaction, pressure control, aeration and vocal abilities. While coordination is essential for normal function, little is known regarding developmental changes or horizons during infancy. Early infancy is a period of high incidence of ADT diseases and symptoms. Detailed data on normal age‐range development is essential for charting crucial periods for focus in prevention and treatment. Stage 1 of this study compiled a multi‐field mega‐database in order to highlight “peak incidence” timings of change. Results indicate changes in many different areas of investigation involving gross ADT anatomy, vocal fold histology, laryngeal chemoreflexes, autonomic control of heart rate and blood pressure, vision accommodation, formant frequency acoustics, audio pattern recognition, hearing, limb control and clinical reportage of SIDS all meet at a nexus of 2 to 4 post‐natal months. This suggests a critical period identifying both change in the region and co‐temporaneous occurrence of diseases and clinicopathologies. Establishing ADT developmental horizons in infants will aid in prevention and treatment during this critical period.

Grant Funding Source: Mount Sinai Summer Research Fellowship
Syntaxin 16 is required for epithelial morphogenesis and single lumen formation
Authors: Jung Jae‐Joon , Inamdar Shivangi M. , Tiwari Ajit , Ye Ding , Lin Fang , Choudhury Amit
Published: June 2021

Formation and maintenance of cell‐cell junctions during developmental, physiological, and pathological conditions requires targeting and trafficking of junctional proteins. Syntaxin (Stx) families of proteins are localized at different subcellular membranes and are involved in intracellular trafficking of junctional proteins by regulating vesicle fusion events. Using MDCK II cell line we show that among various endosome‐Golgi localized Stxs, intracellular levels of Stx16 increases progressively as sparsely placed cells were allowed to attain confluency suggesting Stx16 may play a role in the maintenance of cell‐cell contact. Stx16 depleted stable MDCK II cell line when allowed to form confluent monolayer fail to maintain E‐cadherin at the cell‐cell junction. Stx16 depleted confluent monolayer consistently showed lower transepithelial resistance (TER) relative to control monolayer. As expected when these epithelial cells were cultured in matrigel they formed cyst with a hollow single lumen, cysts formed with stx16‐depleted cells show abnormal spindle orientation that lead to multiple lumen formation. Knockdown of zebrafish syntaxin 16 severely affects kidney morphogenesis and lumen formation in morphants. Taken together our in vitro and in vivo studies established role for syntaxin 16 in the maintenance of cell junction integrity and epithelial lumen morphogenesis.

Grant Funding Source: N/A
Dynamics of Yeast Histone H2A and H2B Phosphorylation in Response to a Double‐Strand Break
Authors: Lee Cheng‐Sheng , Lee Kihoon , Haber James E. , Legube Gaëlle
Published: June 2021

In Saccharomyces cerevisiae, a single double‐strand break (DSB) triggers extensive phosphorylation of histone H2A (known as γ‐H2AX) over ≥ 50 kb on either side of the DSB. This modification is carried out by either Tel1, the ATM homolog, or Mec1, the ATR homolog. We have recently described a second DSB‐induced modification, γ‐H2B, the phosphorylation of the C terminal T129 residue of histone H2B. To understand in detail how γ‐H2AX and γ‐H2B spread along the chromosome from a DSB, we have utilized chromatin immunoprecipitations followed by tiling arrays. γ‐H2AX and γ‐H2B modifications are similar, but there is a marked absence of γ‐H2B near telomeres. We find that there is reduced γ‐H2AX and γ‐H2B modification over strongly transcribed regions and the spreading of γ‐H2AX at the region behind is also impaired. When transcription of the galactose‐regulated genes is turned off by the addition of glucose, γ‐H2AX is restored within 5 min; when these genes are again induced, γ‐H2AX is rapidly lost. The restoration of γ‐H2AX in transcribed regions can be done by Tel1 alone even 7 h after break induction, suggesting that Tel1 remains associated with damaged chromosomes for an extended time. In addition, we show that if a DSB is generated 14 kb from CEN2, γ‐H2AX takes place at regions around all the other centromeres. This modification in trans can be observed even in the absence of formaldehyde crosslinking of the samples.
PtdIns(4)P, the Golgi, and Cancer
Authors: Field Seth J.
Published: June 2021

We have shown that GOLPH3 homologs from yeast (Vps74p) to humans function as PtdIns(4)P effectors (Dippold, et al., Cell 2009). GOLPH3 localizes to the trans‐Golgi via its interaction with PtdIns(4)P. GOLPH3 also interacts with the unconventional myosin MYO18A, linking the Golgi to the actin cytoskeleton, and imparting a tensile force that participates in vesicle budding and in establishing the Golgi's characteristic shape. Unexpectedly, GOLPH3 is also an oncogene commonly amplified in human cancers and capable of enhancing growth factor signaling (Scott, et al., Nature 2009). Thus, GOLPH3 is the first example of an oncogene that functions at the Golgi, raising important questions about its mechanism of transformation and the role of the Golgi in cancer. Our data provide new insights into the function of GOLPH3, and reveal surprising regulation of the Golgi via GOLPH3 with important implications for understanding cancer and its treatment.
Isolation and characterization of Isopentenyl‐diphosphate Isomerase (idi) from marine bacterium, Kocuria gwangalliensis
Authors: Jeong Tae Hyug , Ji Keunho , Jang Na Young , Cho Youn Soo , Kim Young Tae
Published: June 2021

Isoprenoid biosynthesis involves mostly head to tail addition of isopentenyl diphosphate (IPP), to its isomer dimethylallyl diphosphate (DMAPP) synthesizing geranyl diphosphate (GPP). Isopentenyl diphosphate (IPP) isomerase catalyses the interconversion of IPP to dimethylallyl diphosphate (DMAPP). In the present study, the gene coding for Isopentenyl‐diphosphate Isomerase (idi) was isolated from the marine bacterium, Kocuria gwangalliensis. The idi gene coding for IPP isomerase consists of 543 base pairs encoding 180 amino acids residues. The nucleotide sequence of the idi gene was analyzed and compared with that of other species, including K. rhizophila and S. keddieii, and it turned out to be well conserved during evolution. An expression plasmid containing the idi gene was constructed and expressed in E. coli, and produced a recombinant protein of approximately 20 kDa, corresponding to the molecular weight. In order to increase production of astaxanthin, pET‐44a(+)‐idi was co‐transformed into E. coli containing the pCR‐XL‐TOPO‐crt‐full carrying crtEBIYWZ genes required for astaxanthin biosynthesis. This engineered E.coli strain containing both idi gene and astaxanthin biosythesis gene cluster produced 900 ug/g DCW of astaxanthin, resulting 2‐fold increased production of astaxanthin.