News Video | Policy | GPs | Hospitals | Medical | Mental Health | Welfare | Search

 


Obesity, gout and the sluggish immune system

21 May 2014

Obesity, gout and the sluggish immune system

Obesity is recognised as a risk factor for gout, cardiovascular disease, type 2 diabetes and some forms of cancer. What is less well known is that carrying excess weight can also prevent the immune system from functioning correctly. For those prone to gout, this could work in their favour!

The prevalence of obesity is increasing worldwide. In New Zealand almost one in three adults and one in nine children are considered obese. The rates are even higher in Maori (48 percent obese) and Pacific (68 percent obese) adults.

Obesity’s effects on the immune system are thought to underlie some of its connections to chronic diseases. The link seems to be the fat tissue itself. Fat cells have been shown to secrete many factors that local immune cells respond to. This promotes a state of overstimulation of the immune system (chronic inflammation), which impairs normal immune function.

For the past decade Malaghan Institute Arthritis and Inflammation Group Leader Dr Jacquie Harper has been investigating the immune responses that drive gout—a disease that is strongly linked with obesity.

“When foods such as liver, kidneys and sardines are broken down by the body, uric acid is released,” says Dr Harper. “Uric acid has many important health benefits and the body is equipped to deal with it, but only up to a certain point.

“A gout attack is triggered by uric acid crystallising in the joints. The immune system perceives the crystals as a threat and launches an immune response against them. It is the resulting inflammation that causes swelling, reddening of the skin and debilitating pain.”

Uric acid levels are higher in obese individuals, increasing their likelihood that they will develop gout. What has been unclear up until now however, is whether their gout attacks are worse than those in non-obese individuals, because of their existing low level of inflammation. Dr Harper’s research, published recently in Rheumatologywould suggest not.

“In collaboration with Auckland Rheumatologist Associate Professor Nicola Dalbeth and colleagues, we investigated the effect of diet-driven obesity on immune cell activity in a model of gout,” says Dr Harper. “Our study is novel in that we focused specifically on immune cells not associated with fat tissue, to determine the wider implications of obesity on immune function.

“We found that obesity elevates the background inflammatory activity of these immune cells, just as it does with fat-associated immune cells. Interestingly however, rather than making things worse, the presence of the crystals actually decreased background inflammation.”

This is good news for obese individuals prone to gout because it suggests that their gout is no worse than that which occurs in some lean individuals. The bad news however is this study further supports the growing evidence that obesity impairs immune function.

While this work has focused on gout, further research is necessary to determine the broader impact of weight gain and dietary fat on the ability of the immune system to respond to different challenges.

This work was funded by the Wellington Medical Research Foundation and the Auckland Medical Research Foundation.

Publication details:
Shaw OM, Pool B, Dalbeth N, Harper JL The effect of diet-induced obesity on the inflammatory phenotype of non-adipose-resident macrophages in an in vivo model of gout. Rheumatology (Oxford) 2014 May 15 (in press)

About the Malaghan Institute of Medical Research
The Malaghan Institute is New Zealand’s leading medical research institute and is based at Victoria University of Wellington’s Kelburn campus. The Institute operates independently and is a charitable trust. Researchers at the Malaghan Institute are focused on developing innovative ways to harness the strength and potency of the immune system, the body’s own natural defence against disease, to treat cancer, asthma and allergy, arthritis and multiple sclerosis.

www.malaghan.org.nz

ENDS

© Scoop Media

 
 
 
 
 
Culture Headlines | Health Headlines | Education Headlines

 

Architecture:
Ian Athfield Dies In Wellington

New Zealand Institute of Architects: It is with great sadness that we inform Members that Sir Ian Athfield, one of New Zealand's finest architects, has passed away in Wellington. More>>

ALSO:

Wellington Production: New-Look Tracy Brothers Are F.A.B.

ITV and New Zealand’s Pukeko Pictures today released an exclusive preview of the new-look Tracy brothers from this year’s hotly anticipated new series, Thunderbirds Are Go. More>>

ALSO:

Cardinal Numbers:
Pope Francis Names Archbishop From NZ Among New Cardinals

Announcing a list of bishops to be made Cardinals in February Pope Francis named Archbishop John Dew, Archbishop of Wellington, overnight from Rome. On hearing the news of the announcement, Archbishop John Dew said "This news is recognition of the Catholic Church in Aotearoa New Zealand, and the contribution it makes to the global Catholic family." More>>

ALSO:

Nomenclature: Charlotte And Oliver Top Baby Names For 2014

Charlotte and Oliver were the most popular names for newborn girls and boys in 2014... The top 100 girls’ and boys’ names make up a small proportion of the more than 12,000 unique first names registered for children born this year, says Jeff Montgomery, Registrar-General of Births, Deaths and Marriage. More>>

Werewolf: Katniss Joins The News Team

From the outset, the Hunger Games series has dwelt obsessively on the ways that media images infiltrate our public and personal lives... From that grim starting point, Mockingjay Part One takes the process a few stages further. There is very little of the film that does not involve the characters (a) being on screens (b) making propaganda footage to be screened and (c) reacting to what other characters have been doing on screens. More>>

ALSO:

Scoop Review Of Books: Ko Witi Te Kaituhituhi

Witi Ihimaera, the distinguished Māori author and the first Māori to publish a book of short stories and a novel, has adopted a new genre with his latest book. But despite its subtitle, this book is a great deal more than a memoir of childhood. More>>

Werewolf: Rescuing Paul Robeson

Would it be any harder these days, for the US government to destroy the career of a famous American entertainer and disappear them from history – purely because of their political beliefs? You would hope so. In 1940, Paul Robeson – a gifted black athlete, singer, film star, Shakespearean actor and orator – was one of the most beloved entertainers on the planet. More>>

ALSO:

"Not A Competition... A Quest": Chapman Tripp Theatre Award Winners

Big winners on the night were Equivocation (Promising Newcomer, Best Costume, Best Director and Production of the Year), Kiss the Fish (Best Music Composition, Outstanding New NZ Play and Best Supporting Actress), and Watch (Best Set, Best Sound Design and Outstanding Performance). More>>

ALSO:

Get More From Scoop

 
 

LATEST HEADLINES

 
 
 
 
Health
Search Scoop  
 
 
Powered by Vodafone
NZ independent news