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...

Permanently Beat Urinary Tract Infections: Proven Step-by-Step Cure for Urinary Tract Infection and Cystitis. All Natural, Lasting UTI Remedies That ... Infections (Women's Health Expert Series)

Permanently Beat Urinary Tract Infections: Proven Step-by-Step Cure for Urinary Tract Infection and Cystitis. All Natural, Lasting UTI Remedies That ... Infections (Women's Health Expert Series)
by Caroline D Greene (Author)


From the bestselling women's health author Caroline D. Greene Get your copy NOW! In this Book, Medical Researcher and Former Urinary Tract Infection Sufferer Teaches You: How to stop the pain and discomfort caused by your UTI Why the infections keep coming back Which treatment mistakes 98% of women make that actually make matters WORSE Where you're getting the infection from and how to avoid it What you need to do to end the constant cycle of infection - antibiotics - temporary relief - reinfection UTI Diet plan complete with recipes for drinks, breakfast, lunch, diner, and deserts Scroll Up and Hit 'Buy Now' to Take Back Your Life Today! BONUS BOOK! If you buy Permanently Beat Urinary Tract Infections! today, you are also entitled to a FREE copy of the best-selling book: Holistic...

Urinary Tract Infection in the Female

Urinary Tract Infection in the Female
by Stuart L. Stanton (Author), Peter L. Dwyer (Author)


An international team of experts has here assessed the various aspects of clinical management of a difficult problem.

Harrison's Nephrology and Acid-Base Disorders

Harrison's Nephrology and Acid-Base Disorders
by J. Jameson (Author), Joseph Loscalzo (Author)


The authority of Harrison's in a handy, full-color paperback devoted exclusively to Nephrology and Acid-Base Disorders A Doody's Core Title for 2011! 4 STAR DOODY'S REVIEW!
"In the Harrison's tradition, this book integrates pathophysiology with clinical management while outlining discoveries in genetics and molecular biology. It includes some important chapters that are not found in similar books: one on adaptation of the kidney to renal injury (including factors and mechanisms of renal disease progression) and one on hyperuricemia and gout. The introductory chapter on the basic biology of the kidney, covering renal development, function, and physiology, is very well written. This book meets the expected Harrison's standards and reading it is a satisfying experience."--Doody's Review...

Why Isn't My Brain Working?: A Revolutionary Understanding of Brain Decline and Effective Strategies to Recover Your Brain's Health

Why Isn't My Brain Working?: A Revolutionary Understanding of Brain Decline and Effective Strategies to Recover Your Brain's Health
by Dr. Datis Kharrazian (Author)


Losing your memory? Can't focus or concentrate? Do you have brain fog or tire easily? Have you lost your zest for life or motivation? Do people tell you this is all a normal part of aging? If so, your brain may be growing old too fast, or degenerating. Modern diets, a stressful lifestyle, and environmental toxins all take their toll on the brain. This doesn't just happen to seniors-brain disorders and degeneration are on the rise for young and old alike. The good news is the brain is extremely adaptable and wants to get well. You simply have to know how to feed and care for your brain. How do you know if your brain isn't working? See if some of these signs and symptoms of brain degeneration apply to you: Memory loss • brain fog • depression • anxiety • difficulty learning • lack...

The Patient in Room Nine Says He's God

The Patient in Room Nine Says He's God
by Louis Profeta (Author)


A young Jewish doctor prays to a coma patient's Blessed Mother on Christmas Eve, only to have the woman suddenly awakened; there is the voice that tells a too-busy ER doctor to stop a patient walking out, discovering an embolus that would have killed him. The late-night passing of a beloved aunt summons a childhood bully who shows up minutes later, after twenty-five years, to be forgiven and to heal a broken doctor. This ER doctor finds God's opposite in: a battered child's bruises covered over by make-up, a dying patient whose son finally shows up at the end to reclaim the man's high-top sneakers, the rich or celebrity patients loaded with prescription drugs from doctor friends who end up addicted. But, his real outrage is directed at our cavalier treatment of the elderly, If you put a...

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.

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...

DASH Diet for Beginners: A DASH Diet QUICK START GUIDE to Fast Natural Weight Loss, Lower Blood Pressure and Better Health, Including DASH Diet Recipes & 7-Day Meal Plan

DASH Diet for Beginners: A DASH Diet QUICK START GUIDE to Fast Natural Weight Loss, Lower Blood Pressure and Better Health, Including DASH Diet Recipes & 7-Day Meal Plan
by Gina Crawford (Author)


DASH Diet for Beginners - Learn how the DASH diet can drastically improve your health and your weight! *A complete DASH diet guide to living your healthiest life ever!* The DASH diet is a lifelong well-balanced approach to healthy eating promoted by the National Institutes of Health that is based on nutrient-rich whole foods. This book will teach you exactly how to reach and maintain a healthy weight while lowering blood pressure and cholesterol. Change your food - Change your life U.S. News and World Report chose the DASH diet as the best overall diet, the healthiest diet and the best diet for diabetes for four years in a row. It is estimated that hypertension or high blood pressure affects over 1 billion people worldwide. Not only is high blood pressure the leading cause of death,...

Lange Pharmacology Flash Cards, Third Edition (LANGE FlashCards)

Lange Pharmacology Flash Cards, Third Edition (LANGE FlashCards)
by Suzanne Baron (Author), Christoph Lee (Author)


230 cards deliver a fun, fast, high-yield review for the USMLE Step 1 With these cards, you'll be able to: Focus on must-know information for the boards Compare and contrast drugs Understand the basic principles of drug classes that are board relevant and high yield Know mechanisms of action, clinical uses, and side effects Review basic science as well as the clinical aspects of disease

© 2016 BrightSurf.com