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Shin YC, Wu A, Min S, Kim D, Shin W, Eckhardt SG, Fleming RYD, Kim HJ. Abstract 3862: Microbial immunomodulation for enhancing immunotherapeutic efficacy in a patient-specific colorectal cancer chip. Cancer Res 2022. [DOI: 10.1158/1538-7445.am2022-3862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Immune checkpoint inhibitors (ICI) targeting PD-1, PD-L1, or CTLA-4 have shown remarkable therapeutic outcomes in various cancers. However, the therapeutic efficacy of ICI-based immunotherapy in microsatellite stable (MSS) colorectal cancer (CRC) has been extremely limited. Recent studies strikingly revealed that the human gut microbiome controls the efficacy of immune checkpoint blockades. Yet, the effect of the gut microbiome on reinforcing the ICI efficacy in MSS tumors in CRC is unknown. Here, we suggest a microengineered CRC Chip that recapitulates the tumor microenvironment of individual CRC patients by introducing biopsy-derived colonic organoid epithelium. We have built a three-dimensional (3D) lumen-capillary interface under peristalsis-like motions and flow in an oxygen-controlled microenvironment. We leverage this pathomimetic CRC Chip to recapitulate the patient-specific tumor-microbiome-immune axis to demonstrate microbial immunomodulation on the tumor cells and cytotoxic tumor immunity. We co-cultured various human intestinal bacteria in a CRC Chip to assess the immunomodulatory contribution to the tumor epithelium. We found that living Bifidobacterium sp. significantly reduces the PD-L1 on the tumor surface, followed by elevated anti-tumor activity after CD8 T cell-mediated cytotoxic interactions. We envision that our CRC Chip model can potentially reduce the knowledge gap between the bench and bedside. Furthermore, our innovative CRC Chip model may potentially offer a platform to validate the “Druggable microbiome” and the utility of the patient’s avatar model for Precision Medicine.
Citation Format: Yong Cheol Shin, Alexander Wu, Soyoun Min, Daesung Kim, Woojung Shin, S. Gail Eckhardt, R. Y. Declan Fleming, Hyun Jung Kim. Microbial immunomodulation for enhancing immunotherapeutic efficacy in a patient-specific colorectal cancer chip [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3862.
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Affiliation(s)
| | | | - Soyoun Min
- 1The University of Texas at Austin, Austin, TX
| | - Daesung Kim
- 1The University of Texas at Austin, Austin, TX
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Wooten SV, Wolf JS, Mendoza D, Bartholomew JB, Stanforth PR, Stanforth D, Tanaka H, Fleming RYD. The Impact of a Multimodal Sport Science-Based Prehabilitation Program on Clinical Outcomes in Abdominal Cancer Patients: A Cohort Study. Am Surg 2022; 88:2302-2308. [PMID: 35608376 DOI: 10.1177/00031348221103657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The potential for prehabilitation programs to impact clinical outcomes is uncertain in abdominal cancer patients due to the short window of time to intervene and the weakened state of the patients. To improve the effectiveness of prehabilitation intervention, a multimodal sports science approach was implemented. METHODS Prior to cancer-related surgery, 21 patients participated in a 4-week exercise and nutrition prehabilitation program comprised of blood flow restriction exercise (BFR) and a sports nutrition supplement. Retrospective data of 71 abdominal cancer patients who underwent usual preoperative care was used as a comparator control group (CON). At 90 days post-surgery, clinical outcomes were quantified. RESULTS Prehabilitation was associated with a shorter length of hospital stay (P = .02) with 5.5 fewer days (4.7 ± 2.1 vs 10.2 ± 1.2 days in CON) and decreased incidence of any complications (P = .03). Prehabilitation was not related to incidence of serious complications (P = .17) or readmission rate (P = .59). The prehabilitation group recorded 58% more steps on day 5 after surgery (P = .043). DISCUSSION A 4-week home-based prehabilitation program composed of BFR training and sports nutrition supplementation was effective in reducing postoperative complications and length of hospital stay in older patients with abdominal cancer.ClinicalTrials.gov Identifier: NCT04073381.
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Affiliation(s)
- Savannah V Wooten
- Department of Kinesiology and Health Education, 4002The University of Texas at Austin, Austin, TX, USA
| | - J Stuart Wolf
- Department of Surgery and Periopertative Care, 12330The University of Texas at Austin, Austin, TX, USA
| | - Diana Mendoza
- Department of Surgery and Periopertative Care, 12330The University of Texas at Austin, Austin, TX, USA
| | - John B Bartholomew
- Department of Kinesiology and Health Education, 4002The University of Texas at Austin, Austin, TX, USA
| | - Philip R Stanforth
- Department of Kinesiology and Health Education, 4002The University of Texas at Austin, Austin, TX, USA
| | - Dixie Stanforth
- Department of Kinesiology and Health Education, 4002The University of Texas at Austin, Austin, TX, USA
| | - Hirofumi Tanaka
- Department of Kinesiology and Health Education, 4002The University of Texas at Austin, Austin, TX, USA
| | - R Y Declan Fleming
- Department of Surgery and Periopertative Care, 12330The University of Texas at Austin, Austin, TX, USA
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Wang T, Stanforth PR, Fleming RYD, Wolf JS, Stanforth D, Tanaka H. A Mobile App With Multimodality Prehabilitation Programs for Patients Awaiting Elective Surgery: Development and Usability Study. JMIR Perioper Med 2021; 4:e32575. [PMID: 34967752 PMCID: PMC8759016 DOI: 10.2196/32575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/14/2021] [Accepted: 12/19/2021] [Indexed: 11/13/2022] Open
Abstract
Background Complying with a prehabilitation program is difficult for patients who will undergo surgery, owing to transportation challenges and a limited intervention time window. Mobile health (mHealth) using smartphone apps has the potential to remove barriers and improve the effectiveness of prehabilitation. Objective This study aimed to develop a mobile app as a tool for facilitating a multidisciplinary prehabilitation protocol involving blood flow restriction training and sport nutrition supplementation. Methods The app was developed using “Appy Pie,” a noncoding app development platform. The development process included three stages: (1) determination of principles and requirements of the app through prehabilitation research team meetings; (2) app prototype design using the Appy Pie platform; and (3) app evaluation by clinicians and exercise and fitness specialists, technical professionals from Appy Pie, and non–team-member users. Results We developed a prototype of the app with the core focus on a multidisciplinary prehabilitation program with accessory features to improve engagement and adherence to the mHealth intervention as well as research-focused features to evaluate the effects of the program on frailty status, health-related quality of life, and anxiety level among patients awaiting elective surgery. Evaluations by research members and random users (n=8) were consistently positive. Conclusions This mobile app has great potential for improving and evaluating the effectiveness of the multidisciplinary prehabilitation intervention in the format of mHealth in future.
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Affiliation(s)
- Tianyu Wang
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - Philip R Stanforth
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - R Y Declan Fleming
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - J Stuart Wolf
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - Dixie Stanforth
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
| | - Hirofumi Tanaka
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, United States
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Wooten SV, Fleming RYD, Wolf JS, Stray-Gundersen S, Bartholomew JB, Mendoza D, Stanforth PR, Stanforth D, Hernandez LM, Tanaka H. Prehabilitation program composed of blood flow restriction training and sports nutrition improves physical functions in abdominal cancer patients awaiting surgery. Eur J Surg Oncol 2021; 47:2952-2958. [PMID: 34092455 DOI: 10.1016/j.ejso.2021.05.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/04/2021] [Accepted: 05/25/2021] [Indexed: 01/02/2023] Open
Abstract
INTRODUCTION The impact of prehabilitation remains controversial due to a short presurgical waiting period and the diminished capacity of the patient population. A strategy to augment and optimize the effectiveness of prehabilitations for abdominal cancer patients may be found in the unlikely field of sport science. We investigated the use of blood flow restriction training and sport nutrition supplementation to augment functional capacity and increase muscle strength in twenty-four abdominal cancer patients awaiting surgery. MATERIALS AND METHODS The sport science-based program was comprised of blood flow restriction exercise 5 to 6 times per week and a daily sports nutrition supplement containing l-citrulline, creatine monohydrate, and whey protein. RESULTS After 4 weeks of prehabilitation, 6-min walk test, timed up and go, short physical performance battery, 5-chair stand test and physical component score of quality of life were significantly improved (all p < 0.05). Total body and appendicular lean mass as assessed by dual energy X-ray absorptiometry increased by 0.73 ± 1.04 kg (p = 0.004) and 0.42 ± 0.64 kg (p = 0.006), respectively. Total body fat mass and trunk fat mass decreased (p = 0.004 and p = 0.021). There were no significant changes in hand grip strength, fear of falling, the mental component summary of quality of life, or fasting serum concentrations of myostatin, follistatin, and growth hormone. CONCLUSION A multimodal prehabilitation program, which encompasses blood flow restriction training and sports nutrition supplements, is both feasible and effective in improving lean mass and physical function in abdominal cancer patients prior to surgery.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ladia M Hernandez
- Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX, USA
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Olson KA, Fleming RYD, Fox AW, Grimes AE, Mohiuddin SS, Robertson HT, Moxham J, Wolf JS. The Enhanced Recovery After Surgery (ERAS) Elements that Most Greatly Impact Length of Stay and Readmission. Am Surg 2020; 87:473-479. [PMID: 33047966 DOI: 10.1177/0003134820951440] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Enhanced recovery after surgery (ERAS) protocols have been shown to decrease length of stay (LOS) and improve patient outcomes in a wide variety of surgical fields; however, barriers exist preventing the implementation of all elements. We hypothesize that a subset of ERAS elements are most influential on LOS and readmission following colorectal surgery. STUDY DESIGN A retrospective review of 840 patients was performed and their compliance with 24 ERAS components evaluated. Two independent machine-learning statistical algorithms were employed to determine which subset of ERAS elements was most impactful on LOS <3 days and hospital readmission. RESULTS Increasing compliance with ERAS elements had an inverse linear relationship with LOS. Open (vs minimally invasive) surgery was associated with increased LOS. Early mobilization and multimodal pain management are the elements most protective against increased LOS. Readmissions increase with the number of morphine milligram equivalents (MME)/day. The subset of patients who underwent minimally invasive procedures, had multimodal pain control, and less than 16 MME per day were least likely (23%) to have >3-day LOS. Those patients who underwent an open procedure with less than 15 ERAS elements completed were most likely (84%) to have >3-day LOS. CONCLUSION While increasing compliance with ERAS protocols and minimally invasive procedures decrease LOS and readmission overall, a subset of components-multimodal pain control, limited opioid use, and early mobilization-was most associated with decreased LOS and readmission. This study provides guidance on which ERAS elements should be emphasized.
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Affiliation(s)
- Kristofor A Olson
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
| | - R Y Declan Fleming
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
| | - April W Fox
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
| | - Andrew E Grimes
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
| | - S Sameer Mohiuddin
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
| | - Henry T Robertson
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA.,1685 Department of Surgery, Uniformed Services University, Bethesda, MD, USA
| | - Jamie Moxham
- 21981 Ascension Seton Healthcare, Austin, TX, USA
| | - J Stuart Wolf
- 377659 Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas, Austin, TX, USA
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Shin W, Wu A, Min S, Shin YC, Fleming RYD, Eckhardt SG, Kim HJ. Spatiotemporal Gradient and Instability of Wnt Induce Heterogeneous Growth and Differentiation of Human Intestinal Organoids. iScience 2020; 23:101372. [PMID: 32745985 PMCID: PMC7398973 DOI: 10.1016/j.isci.2020.101372] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/22/2020] [Accepted: 07/14/2020] [Indexed: 12/12/2022] Open
Abstract
In a conventional culture of three-dimensional human intestinal organoids, extracellular matrix hydrogel has been used to provide a physical space for the growth and morphogenesis of organoids in the presence of exogenous morphogens such as Wnt3a. We found that organoids embedded in a dome-shaped hydrogel show significant size heterogeneity in different locations inside the hydrogel. Computational simulations revealed that the instability and diffusion limitation of Wnt3a constitutively generate a concentration gradient inside the hydrogel. The location-dependent heterogeneity of organoids in a hydrogel dome substantially perturbed the transcriptome profile associated with epithelial functions, cytodifferentiation including mucin 2 expression, and morphological characteristics. This heterogeneous phenotype was significantly mitigated when the Wnt3a was frequently replenished in the culture medium. Our finding suggests that the morphological, transcriptional, translational, and functional heterogeneity in conventional organoid cultures may lead to a false interpretation of the experimental results in organoid-based studies.
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Affiliation(s)
- Woojung Shin
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton St., Austin, TX 78712, USA
| | - Alexander Wu
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton St., Austin, TX 78712, USA
| | - Soyoun Min
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton St., Austin, TX 78712, USA
| | - Yong Cheol Shin
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton St., Austin, TX 78712, USA
| | - R Y Declan Fleming
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - S Gail Eckhardt
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin, 107 W. Dean Keeton St., Austin, TX 78712, USA; Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; Department of Medical Engineering, Yonsei University College of Medicine, Seoul 03722, Republic of Korea.
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Shin YC, Shin W, Koh D, Wu A, Ambrosini YM, Min S, Eckhardt SG, Fleming RYD, Kim S, Park S, Koh H, Yoo TK, Kim HJ. Three-Dimensional Regeneration of Patient-Derived Intestinal Organoid Epithelium in a Physiodynamic Mucosal Interface-on-a-Chip. Micromachines (Basel) 2020; 11:E663. [PMID: 32645991 PMCID: PMC7408321 DOI: 10.3390/mi11070663] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 07/03/2020] [Accepted: 07/05/2020] [Indexed: 12/29/2022]
Abstract
The regeneration of the mucosal interface of the human intestine is critical in the host-gut microbiome crosstalk associated with gastrointestinal diseases. The biopsy-derived intestinal organoids provide genetic information of patients with physiological cytodifferentiation. However, the enclosed lumen and static culture condition substantially limit the utility of patient-derived organoids for microbiome-associated disease modeling. Here, we report a patient-specific three-dimensional (3D) physiodynamic mucosal interface-on-a-chip (PMI Chip) that provides a microphysiological intestinal milieu under defined biomechanics. The real-time imaging and computational simulation of the PMI Chip verified the recapitulation of non-linear luminal and microvascular flow that simulates the hydrodynamics in a living human gut. The multiaxial deformations in a convoluted microchannel not only induced dynamic cell strains but also enhanced particle mixing in the lumen microchannel. Under this physiodynamic condition, an organoid-derived epithelium obtained from the patients diagnosed with Crohn's disease, ulcerative colitis, or colorectal cancer independently formed 3D epithelial layers with disease-specific differentiations. Moreover, co-culture with the human fecal microbiome in an anoxic-oxic interface resulted in the formation of stochastic microcolonies without a loss of epithelial barrier function. We envision that the patient-specific PMI Chip that conveys genetic, epigenetic, and environmental factors of individual patients will potentially demonstrate the pathophysiological dynamics and complex host-microbiome crosstalk to target a patient-specific disease modeling.
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Affiliation(s)
- Yong Cheol Shin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Woojung Shin
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Domin Koh
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Alexander Wu
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Yoko M. Ambrosini
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - Soyoun Min
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
| | - S. Gail Eckhardt
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
| | - R. Y. Declan Fleming
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
- Department of Surgery and Perioperative Care, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA
| | - Seung Kim
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Sowon Park
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Hong Koh
- Severance Fecal Microbiota Transplantation Center, Severance Hospital, Department of Pediatrics, Yonsei University College of Medicine, Seoul 03722, Korea; (S.K.); (S.P.); (H.K.)
| | - Tae Kyung Yoo
- Department of Computer Art, College of Art and Technology, Chung-Ang University, Seoul 06974, Korea;
| | - Hyun Jung Kim
- Department of Biomedical Engineering, The University of Texas at Austin, Austin, TX 78712, USA; (Y.C.S.); (W.S.); (D.K.); (A.W.); (Y.M.A.); (S.M.)
- Department of Oncology, Dell Medical School, The University of Texas at Austin, Austin, TX 78712, USA; (S.G.E.); (R.Y.D.F.)
- Department of Medical Engineering, College of Medicine, Yonsei University, Seoul 03722, Korea
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Wooten SV, Wolf JS, Bartholomew JB, Mendoza D, Stanforth PR, Stanforth D, Hernandez LM, Nguyen CT, Carneglia JR, Tanaka H, Fleming RYD. The Impact Of Sports Science-based Prehabilitation On Spontaneous Physical Activity After Major Abdominal Cancer Surgery. Med Sci Sports Exerc 2020. [DOI: 10.1249/01.mss.0000686260.86617.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Peerce BE, Fleming RYD, Clarke RD. Inhibition of human intestinal brush border membrane vesicle Na+-dependent phosphate uptake by phosphophloretin derivatives. Biochem Biophys Res Commun 2003; 301:8-12. [PMID: 12535632 DOI: 10.1016/s0006-291x(02)02974-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hyperphosphatemia and II(o) hyperparathyroidism are common and severe complications of chronic renal failure. Reduced dietary phosphorus has been shown to be an effective treatment in reducing serum phosphate and serum PTH. 2(')-Phosphophloretin inhibited small intestine apical membrane Na(+)/phosphate cotransport and reduced serum phosphate in adult rats. 2(')-PP and phosphoesters of phloretin were tested for inhibition of human small intestine brush border membrane alkaline phosphatase activity and for inhibition of Na(+)-dependent phosphate uptake. The IC(50)'s for inhibition of alkaline phosphatase suggested an order of inhibitory potency of 4-PP > phloretin > 4(')-PP > 2(')-PP. Inhibition of Na(+)-dependent phosphate uptake followed the sequence 2(')-PPz.Gt;4(')-PP > 4-PP > phloretin. These results are consistent with 2(')-PP being a specific inhibitor of human intestinal brush border membrane Na(+)/phosphate cotransport.
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Affiliation(s)
- Brian E Peerce
- Department of Physiology and Biophysics, University of Texas Medical Branch, 12th and Mechanic, 2.200 Basic Science Bldg., Galveston, TX 77555-0641, USA.
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Biolo G, Fleming RYD, Maggi SP, Nguyen TT, Herndon DN, Wolfe RR. Inverse regulation of protein turnover and amino acid transport in skeletal muscle of hypercatabolic patients. J Clin Endocrinol Metab 2002; 87:3378-84. [PMID: 12107253 DOI: 10.1210/jcem.87.7.8699] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We have investigated the relationships between the rates of muscle protein synthesis and degradation and of transmembrane transport of selected amino acids in leg skeletal muscle of 19 severely burned patients and 18 normal controls in the postabsorptive state. Patients were studied on the 14 +/- 5 postburn day, and their mean burn size was 66% +/- 18% of total body surface area. Methods were based on the leg arteriovenous balance technique in combination with biopsies of the vastus lateralis muscle and infusions of isotopic tracers of amino acids. Net muscle protein breakdown was greater in the patients because of an 83% increase in the rate of muscle protein degradation. The rate of muscle protein synthesis was also increased in the patients but to a lesser extent than protein degradation, i.e. by 50% with the arteriovenous phenylalanine balance technique and by 49% with the direct tracer incorporation method. The absolute values of inward transport of phenylalanine, leucine, and lysine were not significantly different in the two groups. However, the ability of transport systems to take up amino acids from the bloodstream, as assessed by dividing inward transport by amino acid delivery to leg muscle, were 50-63% lower in the patients. In contrast, outward phenylalanine and lysine transport were 40% and 67% greater in the patients than in the controls, respectively. We conclude the primary alteration in muscle protein metabolism is an acceleration of protein breakdown, and the increase in protein synthesis likely is due to increased intracellular amino acid availability as a result of accelerated breakdown. Transmembrane transport in the outward direction is accelerated, presumably to facilitate the export of amino acids from muscle to other tissues. In contrast, transmembrane transport in the inward direction is impaired relatively to the increased delivery of circulating amino acid to skeletal muscle secondary to accelerated blood flow.
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Affiliation(s)
- Gianni Biolo
- Shriners Burns Hospital, 815 Market Street, Galveston, TX 77550, USA.
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Fleming RYD, Singletary SE. Inflammatory Breast Cancer. Breast Cancer 1999. [DOI: 10.1007/978-1-4612-2146-3_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Abstract
Cancer of the colon and rectum is a significant health problem in the United States. Nearly 50% of the 186,000 patients diagnosed annually with colorectal cancer will eventually die of their disease. Because development of a colorectal carcinoma is most frequently preceded by the development of a well-recognized pre-malignant lesion, screening modalities can significantly impact the incidence and mortality rate of this disease. Population screening employing digital rectal examination, fecal occult blood testing and endoscopic examination of the rectum and colon has been demonstrated to reduce the risk of death from colorectal cancer. Screening regimens should be instituted at an earlier age and with increased frequency for patients in the highest risk categories. Patients who have been treated for a cancer of the colon or rectum should undergo surveillance at regular intervals in an attempt to identify recurrences of disease both in the residual colon and rectum and at distant sites. Most physicians and patients believe that intensive follow-up strategies will afford improved survival and quality of life, however few randomized studies examining the utility of intensive follow-up programs have been performed and the quality of cancer-related follow-up literature is generally poor. Good-quality clinical trials are needed to sort out which tests make a difference in the patient's long-term outcome. The algorithm for surveillance for recurrence in the future may be altered as newer testing modalities are developed.
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Affiliation(s)
- R Y Declan Fleming
- Department of Surgery, The University of Texas Medical Branch, Galveston, USA.
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Biolo G, Declan Fleming RY, Wolfe RR. Physiologic hyperinsulinemia stimulates protein synthesis and enhances transport of selected amino acids in human skeletal muscle. J Clin Invest 1995; 95:811-9. [PMID: 7860765 PMCID: PMC295560 DOI: 10.1172/jci117731] [Citation(s) in RCA: 292] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We have investigated the mechanisms of the anabolic effect of insulin on muscle protein metabolism in healthy volunteers, using stable isotopic tracers of amino acids. Calculations of muscle protein synthesis, breakdown, and amino acid transport were based on data obtained with the leg arteriovenous catheterization and muscle biopsy. Insulin was infused (0.15 mU/min per 100 ml leg) into the femoral artery to increase femoral venous insulin concentration (from 10 +/- 2 to 77 +/- 9 microU/ml) with minimal systemic perturbations. Tissue concentrations of free essential amino acids decreased (P < 0.05) after insulin. The fractional synthesis rate of muscle protein (precursor-product approach) increased (P < 0.01) after insulin from 0.0401 +/- 0.0072 to 0.0677 +/- 0.0101%/h. Consistent with this observation, rates of utilization for protein synthesis of intracellular phenylalanine and lysine (arteriovenous balance approach) also increased from 40 +/- 8 to 59 +/- 8 (P < 0.05) and from 219 +/- 21 to 298 +/- 37 (P < 0.08) nmol/min per 100 ml leg, respectively. Release from protein breakdown of phenylalanine, leucine, and lysine was not significantly modified by insulin. Local hyperinsulinemia increased (P < 0.05) the rates of inward transport of leucine, lysine, and alanine, from 164 +/- 22 to 200 +/- 25, from 126 +/- 11 to 221 +/- 30, and from 403 +/- 64 to 595 +/- 106 nmol/min per 100 ml leg, respectively. Transport of phenylalanine did not change significantly. We conclude that insulin promoted muscle anabolism, primarily by stimulating protein synthesis independently of any effect on transmembrane transport.
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Affiliation(s)
- G Biolo
- Department of Internal Medicine, University of Texas Medical Branch, Galveston
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