Science Current Events | Science News | Brightsurf.com
 

Bacterial toxin may play important role in acute, chronic urinary tract infections

January 19, 2012
Alpha-hemolysin triggers bladder cell shedding

SALT LAKE CITY - Researchers from the University of Utah have identified a process by which the most common types of urinary tract infection-causing bacteria are able to trigger bladder cell shedding and disable immune responses. According to this new study, published in the Jan. 19, 2012, issue of Cell Host & Microbe, α-hemolysin, a toxin secreted by many strains of Escherichia coli (E. coli), may play an important, unexpected role during both the establishment and persistence of urinary tract infections.

Urinary tract infections (UTIs) are among the most common infectious diseases worldwide. Each year, 15 million U.S. women have a UTI and nearly 50 percent of women will have at least one UTI in their lifetime. Bacteria known as uropathogenic E. coli (UPEC) are the leading cause of both acute and chronic urinary tract infections. UPEC invade cells on the surface of the bladder, where it can stimulate exfoliation, or shedding, of bladder cells.

"Exfoliation of bladder cells can be viewed as a double-edged sword since it may benefit both the host and the invading bacteria," says Matthew Mulvey, Ph.D., associate professor of pathology at the University of Utah and co-author on the study. "While shedding helps to get rid of infected cells, it can also promote spread of the bacteria both within and outside of the urinary tract. The goal of our investigation was to uncover possible mechanisms by which UPEC might prime bladder cells for shedding."

Mulvey and Bijaya Dhakal, Ph.D., U of U postdoctoral fellow in pathology, found that infection of bladder cells with UPEC led to degradation of a protein called paxillin, which helps to regulate cell adhesion. They discovered that paxillin degradation was stimulated by α-hemolysin (HlyA), a toxin secreted by UPEC, which inserts into bladder cell membranes. HlyA itself does not act to break down paxillin, but Mulvey and Dhakal found that HlyA caused increased activation of a protein-degrading enzyme called mesotrypsin.

"Our data indicate that mesotrypsin is at least partially responsible for paxillin degradation in the UPEC-infected bladder cells," says Mulvey. "This finding is unexpected and intriguing because, although mesotrypsin has been implicated in bladder and other cancers, as well as the shedding of skin cells, its function is still largely undefined."

When UPEC infect bladder cells, the bacteria either multiply or persist in an inactive state for days or even weeks. This persistence creates intracellular reservoirs of bacteria, which are thought contribute to chronic or recurrent infections. Mulvey and Dhakal found that HlyA triggers not only paxillin degeneration, but also breakdown of key proteins involved in cellular responses to infection. The investigators also discovered that the effects of HlyA are not limited to bladder cells. HlyA stimulated protein degradation in macrophages, key immune cells responsible for destroying bacteria, as well. These disruptions of the normal immune response to bacterial invasion may help to explain why UTIs can persist or recur, even in otherwise healthy individuals and in the presence of antibiotics.

"UTIs caused by UPEC strains that secrete HlyA lead to more severe clinical symptoms and tissue damage," says Mulvey. "HlyA is also associated with other closely related strains of E. coli that cause pneumonia, meningitis or serious bloodstream infections. So, in addition to furthering our understanding of UTIs, this study may help to shed light on the mechanisms of other infectious diseases."


University of Utah Health Sciences



More Chronic Urinary Tract Infection Current Events and Chronic Urinary Tract Infection News Articles

UTI Healing Manual: How to Quickly and Naturally Cure Urinary Tract Infections and Never Experience Them Again

UTI Healing Manual: How to Quickly and Naturally Cure Urinary Tract Infections and Never Experience Them Again
by Doctor Scott Health


Natural UTI Healing: The POWER of Antibiotics without the Harmful Consequences
From the author of popular natural health blog, DoctorScottHealth.com, Scott E. McLeod, PharmD
NEW: Take advantage of the limited introductory price of only $2.99

* Looking to heal your UTI inexpensively while avoiding a doctor visit and harmful antibiotics?

* Sick of recurrent infections stealing your life away?

In this Book, Trained Pharmacist, Medical Researcher and Health Coach Teaches You How To:
• Rapidly eliminate UTIs with a practical 6-step plan
• Prevent recurrent infections using the "UTI Do's and Don'ts"
• Harness the power of miraculous supplements, herbs, foods and remedies
• Kill those stubborn infections by...

Pathophysiology: The Biologic Basis for Disease in Adults and Children, 7e

Pathophysiology: The Biologic Basis for Disease in Adults and Children, 7e
by Kathryn L. McCance (Editor), Sue E. Huethe (Editor)


With easy-to-read, in-depth descriptions of disease, disease etiology, and disease processes, Pathophysiology: The Biologic Basis for Disease in Adults and Children, 7th Edition helps you understand the most important and the most complex pathophysiology concepts. More than 1,200 full-color illustrations and photographs make it easier to identify normal anatomy and physiology, as well as alterations of function. This edition includes a NEW Epigenetics and Disease chapter along with additional What’s New boxes highlighting the latest advances in pathophysiology. Written by well-known educators Kathryn McCance and Sue Huether, and joined by a team of expert contributors, this resource is the most comprehensive and authoritative pathophysiology text available!Over 1,200 full-color...

Herbs for the Urinary Tract

Herbs for the Urinary Tract
by Michael Moore (Author)


Michael Moore fuses the holistic and the scientific to show how to identify and deal with problems concerning the urinary tract. Diet, stress and constitution can all be contributing factors to many difficulties. Remedies are drawn from diet and lifestyle changes, and from safe, simple herbal teas.

Pharmacotherapy Flash Cards

Pharmacotherapy Flash Cards
by Jeremy Johnson (Author), Michelle Condren (Author), Kimberly Crosby (Author), Ann Lloyd (Author), Kelly Murray (Author)


238 Q&A cards sharpen your therapeutic decision-making skills "These cards offer concise yet detailed case studies for students to review current pharmacotherapeutic options for many of the commonly encountered disease states....Students might find these cards to be a very helpful in addition to their therapeutics courses to help them retain knowledge through the use of real-life clinical scenarios. 3 Stars."--Doody's Review Service
These 238 Q&A cards provide a complete review of pharmacotherapeutic concepts for the major disease states most often encountered in practice Emphasizes evidence-based therapeutic decision making and drug therapy monitoring Each card features a case and therapeutic question Key facts are included for the drug or drug class that correctly answers the...

Abnormal Psychology: An Integrative Approach, 7th Edition

Abnormal Psychology: An Integrative Approach, 7th Edition
by David H. Barlow (Author), V. Mark Durand (Author)


ABNORMAL PSYCHOLOGY: AN INTEGRATIVE APPROACH, Seventh Edition, is the perfect book to help you succeed in your abnormal psychology course! Authors Barlow and Durand show you how psychological disorders are rooted in multiple factors: biological, psychological, cultural, social, familial, and even political. You can test your understanding of topics with the text's built-in concept checks and chapter quizzes.

Urological Men's Health: A Guide for Urologists and Primary Care Physicians (Current Clinical Urology)

Urological Men's Health: A Guide for Urologists and Primary Care Physicians (Current Clinical Urology)
by Daniel A. Shoskes (Editor)


Urological Men’s Health: A Guide for Urologists and Primary Care Physicians covers the major urologic conditions that have an impact on the health and well being of the adult male. It opens with an overview of general men's preventative health, as practiced by a world leading Executive Health center. The volume covers the major genitourinary malignancies and addresses the latest controversies in screening and treatment selection. This is followed by coverage of the conditions that don't shorten life but have major impact on quality of life and health care expenditure: BPH, urinary incontinence, infertility, urethral strictures, erectile dysfunction, urinary tract infections and chronic pelvic pain. Also included are chapters on herbal and complementary therapy, psychological and...

Essentials of Abnormal Psychology

Essentials of Abnormal Psychology
by Vincent Mark Durand (Author), David H. Barlow (Author)


Revised to reflect DSM-5, this briefer version of Durand and Barlow's widely used book fully describes abnormal psychology through the authors' standard-setting integrative approach--the most modern, scientifically valid method for studying the subject. Through this approach, readers learn that psychological disorders are rarely caused by a single influence, but rooted in the interaction among multiple factors: biological, psychological, cultural, social, familial, and even political. A conversational writing style, consistent pedagogy, and real case profiles--95 percent from the authors' own case files--provide a realistic context for the scientific findings of the book. In addition, these features ensure that readers never lose sight of the fact that real people are behind the DSM-5...

Clinical Companion to Medical-Surgical Nursing: Assessment and Management of Clinical Problems, 9e (Lewis, Clinical Companion to Medical-Surgical Nursing: Assessment and Management of C)

Clinical Companion to Medical-Surgical Nursing: Assessment and Management of Clinical Problems, 9e (Lewis, Clinical Companion to Medical-Surgical Nursing: Assessment and Management of C)
by Sharon L. Lewis RN PhD FAAN (Author), Shannon Ruff Dirksen RN PhD (Author), Margaret M. Heitkemper RN PhD FAAN (Author), Linda Bucher RN PhD CEN (Author)


Disorders section covers commonly encountered medical-surgical conditions in a consistent, clinically relevant presentation that includes: Definition/DescriptionPathophysiologyClinical ManifestationsComplicationsDiagnostic StudiesCollaborative Care (including Drug Therapy, where relevant)Nursing Management GoalsNursing Diagnoses (using the most current NANDA terminology)Nursing InterventionsPatient and Caregiver TeachingTreatments and Procedures section provides need-to-know information on common medical-surgical treatments and procedures.Reference Appendix features key reference information commonly used in nursing practice, including laboratory values, commonly used formulas, and Spanish translations of key phrases.Patient teaching content is highlighted with a special icon, identifying...

The Survival Medicine Handbook: A Guide for When Help is Not on the Way

The Survival Medicine Handbook: A Guide for When Help is Not on the Way
by Joseph Alton (Author), Amy Alton (Author)


The Survival Medicine Handbook(tm) is a guide for those who want to be medically prepared for any disaster where help is NOT on the way. This book is written by Joe Alton, M.D. and Amy Alton, A.R.N.P., the premiere Medical Preparedness Professionals from the top ten survival website www.doomandbloom.net. This book is available in print and kindle, and print book buyers can take advantage of Kindle's matchbook program to also buy the digital version for just $2.99 (normal retail $24.99). The expanded second edition of the 3 category Amazon bestseller (Survival Skills, Disaster Relief, Safety/First Aid) is geared to enable the non-medical professional to deal with all the likely issues they will encounter in catastrophic scenarios. The Survival Medicine Handbook (tm) is not your standard...

Lippincott Illustrated Reviews: Pharmacology 6th edition (Lippincott Illustrated Reviews Series)

Lippincott Illustrated Reviews: Pharmacology 6th edition (Lippincott Illustrated Reviews Series)
by Karen Whalen PharmD BCPS (Author)


Lippincott Illustrated Reviews: Pharmacology, Sixth Edition, is the updated, enhanced version of the student-favorite resource for essentials of medical pharmacology. The first-and-best resource, the Lippincott Illustrated Reviews series features clear, effective writing and hundreds of illustrations for ideal rapid review and the assimilation of complex information. Clear, sequential images present mechanisms of action and focus on showing rather than telling students how drugs work. New edition features:
All NEW chapters on Drugs of Abuse, Drugs for Obesity, Antihistamines, Drugs for Urologic Disorders, Drugs for Hematopoietic Disorders, Drugs for Dermatological Disorders, and Drugs for Bone DisordersOver 380 study questions!Nearly 600 annotated, full-color illustrations visually...

© 2015 BrightSurf.com