Glucose transport into everted sacs of the small intestine of mice

2013 ◽  
Vol 37 (4) ◽  
pp. 415-426 ◽  
Author(s):  
Kirk L. Hamilton ◽  
A. Grant Butt
Keyword(s):  
Small Intestine ◽  
Cell Model ◽  
Group Discussion ◽  
Glucose Absorption ◽  
Cellular Model ◽  
Basic Principles ◽  
Laboratory Exercise ◽  
Hands On ◽  
Second Year ◽  
Physiology Students

The Na+-glucose cotransporter is a key transport protein that is responsible for absorbing Na+ and glucose from the luminal contents of the small intestine and reabsorption by the proximal straight tubule of the nephron. Robert K. Crane originally described the cellular model of absorption of Na+ and glucose by a “cotransport process” in 1960. Over the past 50+ yr, numerous groups have tested and verified Crane's hypothesis. Eventually, Wright and colleagues cloned the Na+-glucose cotransporter (SGLT1; the product of the SLC5A1 gene) in 1987. This article provides a “hands-on” laboratory exercise using the everted mouse jejunal preparation (everted sac) that allows students to investigate various components of the Na+-glucose cotransport absorptive cell model (e.g., Na+ dependence of SGLT1, inhibition of SGLT1, and inhibition of Na+-K+-ATPase). Additionally, the laboratory exercise includes a case-based study of glucose-galactose malabsorption in which the students conduct an internet search and participate in a small-group discussion during the laboratory period to better understand the basic principles and functions of the Na+-glucose absorptive process of the small intestine. This laboratory exercise was introduced into the second-year undergraduate physiology curriculum in 2008, and >850 physiology students have participated in this laboratory exercise. The students have produced very robust and reproducible data that clearly illustrate the theory of the cellular model for Na+-glucose absorption by the jejunum.

scholarly journals “DREAMS AND REALITY”: DESIGNING A LESSON PLAN FOR THE SECOND-YEAR STUDENTS MAJORING IN ORIENTAL PHILOLOGY

2019 ◽  
pp. 55-61
Author(s):  
Tetiana Kolodko
Keyword(s):  
Lesson Plan ◽  
Group Discussion ◽  
Foreign Languages ◽  
European Language ◽  
Basic Principles ◽  
Student Centered ◽  
Approach To Teaching ◽  
Second Year ◽  
Western European ◽  
Speaking Skills

The publication is a lesson plan on the topic “Dreams and Reality” within “General course of Western European language” for the second-year students majoring in Oriental Philology. The lesson is aimed at enhancing integrated English skills with a particular emphasis on speaking skills such as dialogical interaction, expressing opinion in a monologue and group discussion. Phonetic skills are enhanced through listening and reciting poetry. All the exercises suggested by the teacher meet the basic principles of communicative, student-centered approach to teaching foreign languages.

Rice Albumin Hydrolysates Suppress Glucose Absorption from the Small Intestine by Dual Function

2020 ◽  
Author(s):  
Hitomi Kumagai ◽  
Shigenobu Ina ◽  
Aya Hamada ◽  
Chiaki Sugimoto ◽  
Yusuke Yamaguchi,
Keyword(s):  
Small Intestine ◽  
Glucose Absorption ◽  
Dual Function

Indigenous Medicinal Plants and Practices in Cagraray Island: Resources for Culture-Based Lessons in Biology

2021 ◽  
pp. 002205742098870
Author(s):  
Michael B. Bibon
Keyword(s):  
Medicinal Plants ◽  
Conceptual Understanding ◽  
Group Discussion ◽  
Indigenous Medicine ◽  
Entry Points ◽  
Hands On ◽  
Cultural Appreciation ◽  
Quantitative Data Analysis ◽  
K 12 ◽  
Journal Entries

The study aimed to develop culture-based lessons in Biology 9, integrating indigenous medicinal plants and practices in Cagraray Island. These developed lessons were designed incorporating features of research results, problem-based approach, active learning, and culture- or context-based teaching. The accounts from eight folk healers revealed the abundance of indigenous medicinal plants and practices for treating wounds, hypertension, anemia, cough and colds, and asthma. These illnesses were used as springboard for the development of five culture-based lessons with entry points in the K - 12 curriculum. Implemented to 45 Grade 9 learners for five consecutive days at Cawayan National High School, the culture-based lessons were found effective in developing learning outcomes like conceptual understanding, metacognition, science process skills, and cultural appreciation using quantitative data analysis ( p < .05). Qualitative data also supported these findings through Focus-Group Discussion (FGD), journal entries, interviews, and observations. Educational philosophy for culture-based learning revealed the need to incorporate hands-on activities producing concrete evidences for culture-based learning. In general, the study concluded with the potentiality of using indigenous medicine as resources for culture-based lessons in biology. For further study, it is recommended to design and develop more studies about local medicinal plants so they can be integrated, as well as multiple cultural facets, to culture-based lessons.

scholarly journals Mechanisms of Glucose Absorption in the Small Intestine in Health and Metabolic Diseases and Their Role in Appetite Regulation

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2474
Author(s):  
Lyudmila V. Gromova ◽  
Serguei O. Fetissov ◽  
Andrey A. Gruzdkov
Keyword(s):  
Small Intestine ◽  
Blood Glucose ◽  
Metabolic Diseases ◽  
Glucose Absorption ◽  
Cellular Mechanisms ◽  
Physiological Conditions ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
New Strategy ◽  
Intestinal Glucose Absorption

The worldwide prevalence of metabolic diseases such as obesity, metabolic syndrome and type 2 diabetes shows an upward trend in recent decades. A characteristic feature of these diseases is hyperglycemia which can be associated with hyperphagia. Absorption of glucose in the small intestine physiologically contributes to the regulation of blood glucose levels, and hence, appears as a putative target for treatment of hyperglycemia. In fact, recent progress in understanding the molecular and cellular mechanisms of glucose absorption in the gut and its reabsorption in the kidney helped to develop a new strategy of diabetes treatment. Changes in blood glucose levels are also involved in regulation of appetite, suggesting that glucose absorption may be relevant to hyperphagia in metabolic diseases. In this review we discuss the mechanisms of glucose absorption in the small intestine in physiological conditions and their alterations in metabolic diseases as well as their relevance to the regulation of appetite. The key role of SGLT1 transporter in intestinal glucose absorption in both physiological conditions and in diabetes was clearly established. We conclude that although inhibition of small intestinal glucose absorption represents a valuable target for the treatment of hyperglycemia, it is not always suitable for the treatment of hyperphagia. In fact, independent regulation of glucose absorption and appetite requires a more complex approach for the treatment of metabolic diseases.

scholarly journals Generation of tetracycline-controllable CYP3A4-expressing Caco-2 cells by the piggyBac transposon system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Moe Ichikawa ◽  
Hiroki Akamine ◽  
Michika Murata ◽  
Sumito Ito ◽  
Kazuo Takayama ◽  
...  
Keyword(s):  
Small Intestine ◽  
Drug Absorption ◽  
Cell Model ◽  
Negative Effects ◽  
Piggybac Transposon ◽  
Drug Metabolizing Enzyme ◽  
Metabolizing Enzyme ◽  
Cyp3a4 Expression

AbstractCaco-2 cells are widely used as an in vitro intestinal epithelial cell model because they can form a monolayer and predict drug absorption with high accuracy. However, Caco-2 cells hardly express cytochrome P450 (CYP), a drug-metabolizing enzyme. It is known that CYP3A4 is the dominant drug-metabolizing enzyme in human small intestine. In this study, we generated CYP3A4-expressing Caco-2 (CYP3A4-Caco-2) cells and attempted to establish a model that can simultaneously evaluate drug absorption and metabolism. CYP3A4-Caco-2 cells were generated by piggyBac transposon vectors. A tetracycline-controllable CYP3A4 expression cassette (tet-on system) was stably transduced into Caco-2 cells, thus regulating the levels of CYP3A4 expression depending on the doxycycline concentration. The CYP3A4 expression levels in CYP3A4-Caco-2 cells cultured in the presence of doxycycline were similar to or higher than those of adult small intestine. The CYP3A4-Caco-2 cells had enough ability to metabolize midazolam, a substrate of CYP3A4. CYP3A4 overexpression had no negative effects on cell proliferation, barrier function, and P-glycoprotein activity in Caco-2 cells. Thus, we succeeded in establishing Caco-2 cells with CYP3A4 metabolizing activity comparable to in vivo human intestinal tissue. This cell line would be useful in pharmaceutical studies as a model that can simultaneously evaluate drug absorption and metabolism.

scholarly journals Effect of mazindol on glucose absorption in everted rat small intestine.

1986 ◽  
Vol 87 (6) ◽  
pp. 649-654
Author(s):  
Masahiko TSUCHIYA ◽  
Shuji INOUE ◽  
Masayuki SATTA ◽  
Hideki YOSHIMURA ◽  
Masataka ARITA ◽  
...  
Keyword(s):  
Small Intestine ◽  
Glucose Absorption ◽  
Rat Small Intestine

Regulation of intestinal glucose transport

1992 ◽  
Vol 70 (9) ◽  
pp. 1201-1207 ◽  
Author(s):  
D. J. Philpott ◽  
J. D. Butzner ◽  
J. B. Meddings
Keyword(s):  
Small Intestine ◽  
Glucose Transport ◽  
Intestinal Adaptation ◽  
Basolateral Membrane ◽  
Intestinal Transport ◽  
Glucose Absorption ◽  
Dietary Carbohydrate ◽  
Adaptive Responses ◽  
Carbohydrate Levels ◽  
Specific Regulation

The small intestine is capable of adapting nutrient transport in response to numerous stimuli. This review examines several possible mechanisms involved in intestinal adaptation. In some cases, the enhancement of transport is nonspecific, that is, the absorption of many nutrients is affected. Usually, increased transport capacity in these instances can be attributed to an increase in intestinal surface area. Alternatively, some conditions induce specific regulation at the level of the enterocyte that affects the transport of a particular nutrient. Since the absorption of glucose from the intestine is so well characterized, it serves as a useful model for this type of intestinal adaptation. Four potential sites for the specific regulation of glucose transport have been described, and each is implicated in different situations. First, mechanisms at the brush-border membrane of the enterocyte are believed to be involved in the upregulation of glucose transport that occurs in streptozotocin-induced diabetes mellitus and alterations in dietary carbohydrate levels. Also, factors that increase the sodium gradient across the enterocyte may increase the rate of glucose transport. It has been suggested that an increase in activity of the basolaterally located Na+–K+ ATPase could be responsible for this phenomena. The rapid increase in glucose uptake seen in hyperglycemia seems to be mediated by an increase in both the number and activity of glucose carriers located at the basolateral membrane. More recently, it was demonstrated that mechanisms at the basolateral membrane also play a role in the chronic increase in glucose transport observed when dietary carbohydrate levels are increased. Finally, alterations in tight-junction permeability enhance glucose absorption from the small intestine. The possible signals that prompt these adaptive responses in the small intestine include glucose itself and humoral as well as enteric nervous interactions.Key words: intestinal transport, glucose transport, intestinal adaptation.

Teaching calcium-induced calcium release in cardiomyocytes using a classic paper by Fabiato

2008 ◽  
Vol 32 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Willmann Liang
Keyword(s):  
Teaching And Learning ◽  
Calcium Release ◽  
Cell Model ◽  
Learning Experience ◽  
Review Article ◽  
Supporting Evidence ◽  
Cardiac Sarcoplasmic Reticulum ◽  
Technical Issues ◽  
Calcium Induced Calcium Release ◽  
Physiology Students

This teaching paper utilizes the materials presented by Dr. Fabiato in his review article entitled “Calcium-induced release of calcium from the cardiac sarcoplasmic reticulum.” In the review, supporting evidence of calcium-induced calcium release (CICR) is presented. Data concerning potential objections to the CICR theory are discussed as well. In closing, technical issues associated with the skinned cell model are mentioned. Based on this review article, teaching and learning points are put forth in this article to highlight two concepts: 1) the regulatory mechanisms of CICR in cardiomyocytes and 2) the recognition of contradicting hypotheses and limitations in experimental design. The first concept is certainly an important one for physiology students. The second concept is universally applicable to researchers in all fields of science. It is thus the aim of this article to cultivate a rewarding teaching and learning experience for both instructors and students.

scholarly journals Absorption and metabolism of glucose by the mesenteric-drained viscera of sheep fed on dried-grass or ground, maize-based diets

1985 ◽  
Vol 54 (2) ◽  
pp. 449-458 ◽  
Author(s):  
A. N. Janes ◽  
T. E. C. Weekes ◽  
D. G. Armstrong
Keyword(s):  
Small Intestine ◽  
Turnover Rate ◽  
Glucose Utilization ◽  
Venous Blood ◽  
Glucose Production ◽  
Glucose Absorption ◽  
Endogenous Glucose Production ◽  
Whole Body ◽  
Glucose Turnover ◽  
Total Glucose

1. Sheep fitted with re-entrant canulas in the proximal duodenum and terminal ileum were used to determine the amount of α-glucoside entering, and apparently disappearing from, the small intestine when either dried-grass or ground maize-based diets were fed. The fate of any α-glucoside entering the small intestine was studied by comparing the net disappearance of such a-glucoside from the small intestine with the absorption of glucose into the mesenteric venous blood.2. Glucose absorption from the small intestine was measured in sheep equipped with catheters in the mesenteric vein and carotid artery. A continuous infusion of [6-3H]glucose was used to determine glucose utilization by the mesenteric-drained viscera and the whole-body glucose turnover rate (GTR).3. The amounts of α-glucoside entering the small intestine when the dried-grass and maize-based diets were given were 13.9 (SE 1.5) and 95.4 (SE 16.2) g/24 h respectively; apparent digestibilities of such α-glucoside in the small intestine were 60 and 90% respectively.4. The net absorption of glucose into the mesenteric venous blood was —2.03 (SE 1.20) and 19.28 (SE 0.75) mmol/h for the dried-grass and maize-based diets respectively. Similarly, total glucose absorption amounted to 1.52 (SE 1.35) and 23.33 (SE 1.86) mmol/h (equivalent to 7 and 101 g/24 h respectively). These values represented 83 and 11 1% of the a-glucoside apparently disappearing from the small intestine, determined using the re-entrant cannulated sheep.5. Total glucose absorption represented 8 and 61% of the whole-body GTR for the dried-grass and maize-based diets respectively. Endogenous glucose production was significantly lower when the sheep were fed on the maize-based diet compared with the dried-grass diet.6. The mesenteric-drained viscera metabolized a small amount of glucose, equivalent to 234 and 17% of the total glucose absorbed for the dried-grass and maize-based diets respectively.7. It is concluded that a large proportion of the starch entering the small intestine of sheep given a maize-based diet is digested and absorbed as glucose, and thus contributes to the whole-body GTR.

scholarly journals CAN VIRTUAL REALITY BE AS GOOD AS OPERATING ROOM TRAINING? EXPERIENCE FROM A RESIDENCY PROGRAM IN GENERAL SURGERY

2018 ◽  
Vol 31 (4) ◽  
Author(s):  
Bruno Della Mea GASPERIN ◽  
Thamyres ZANIRATI ◽  
Leandro Totti Cavazzola
Keyword(s):  
Virtual Reality ◽  
Operating Room ◽  
General Surgery ◽  
Training Experience ◽  
Total Procedure Time ◽  
Significant Difference ◽  
Hands On ◽  
Second Year ◽  
Practice Time

ABSTRACT Background: The increasingly intense usage of technology applied to videosurgery and the advent of robotic platforms accelerated the use of virtual models in training surgical skills. Aim: To evaluate the performance of a general surgery department’s residents in a video-simulated laparoscopic cholecystectomy in order to understand whether training with virtual reality is sufficient to provide the skills that are normally acquired in hands-on experience at the operating room. Methods: An observational study with twenty-five first- and second-year general surgery residents. Each subject performed three video-laparoscopic cholecystectomies under supervision in a simulator. Only the best performance was evaluated in the study. Total number of complications and total procedure time were evaluated independently. The groups were defined according to total practice time (G1 and G2) and the year of residency (R1 and R2), each being analysed separately. Results: Twenty-one residents finished the three practices, with four follow-up losses. Mean practice time was 33.5 hours. Lowering of the rate of lesions in important structures could be identified after a level of proficiency of 60%, which all participants obtained regardless of previous in vivo experience. No significant difference between the R1 and R2 groups was observed. Conclusion: Learning in groups R1 and R2 was equal, regardless of whether previous practice was predominantly in vivo (R2) or with virtual reality (R1). Therefore, it is possible to consider that skills obtained in virtual reality training are capable of equalising the proficiency of first- and second-year residents, being invaluable to increase patient safety and homogenise learning of basic surgical procedures.

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