(21-04-2017) Gut microbes contribute to age-associated inflammation, mouse study shows
Inflammation increases with age and is a strong risk factor for death in the elderly, but the underlying cause has not been clear. A study published April 12 in Cell Host & Microbe reveals that gut microbes are one of the culprits behind age-associated inflammation and premature death in mice. Imbalances in the composition of gut microbes in older mice cause the intestines to become leaky, allowing the release of bacterial products that trigger inflammation and impair immune function.
"To date, the only things you can do to reduce your age-associated inflammation are eat a healthy diet, exercise, and manage any chronic inflammatory conditions to the best of your ability," says senior author Dawn Bowdish (@MsMacrophage) of the Michael G. DeGroote Institute for Infectious Disease Research at McMaster University. "We hope that in the future we will be able use drugs or pre- or probiotics to increase the barrier function of the gut to keep the microbes in their place and reduce age-associated inflammation and all the bad things that come with it."
Age is associated with an increase in levels of tumor necrosis factor (TNF) and other pro-inflammatory cytokines in the bloodstream and tissues. Individuals with high levels of these inflammatory molecules are more likely to be frail, hospitalized, and less independent; are more susceptible to certain types of infections; and have a variety of chronic, late-life diseases such as dementia and cardiovascular disease, as well as higher death rates. Some have proposed that age-associated inflammation is caused by accumulating wear and tear on our immune cells, while others have suggested that it is caused by immune cells dealing with chronic viral infections. But evidence supporting these hypotheses has been elusive, and the underlying cause of age-associated inflammation has remained unknown.
Bowdish and her colleagues raised mice in germ-free conditions and compared them to their conventionally raised counterparts. Strikingly, the germ-free mice did not show an age-related increase in intestinal permeability or in levels of bacterial products or pro-inflammatory cytokines in the bloodstream, in contrast to conventionally raised mice. Moreover, a higher proportion of germ-free mice lived to the ripe old age of 600 days, and macrophages derived from older germ-free mice maintained anti-microbial activity. Taken together, these findings demonstrate that age-related changes in the gut microbiome weaken the intestinal barrier, leading to the release of bacterial products that promote inflammation, impair immune function, and reduce lifespan.
Additional experiments showed that the relationship between inflammation and the microbiome is bidirectional. In TNF-deficient mice, which are protected from inflammation, age-related changes in the composition of gut microbes were not observed. Moreover, treatment with an anti-TNF drug approved for human use reversed age-related changes in the microbiome.
"We assume that this is because if we reduce inflammation, we improve immune function, and if we improve immune function, we maintain the ability to farm a healthy gut microbiota, but we don't know for sure yet," Bowdish says. "We also believe that targeting age-associated inflammation will improve immune health and are investigating repurposing drugs that are already on the market and developing novel strategies or therapeutics to this effect."
In future studies, Bowdish and her collaborators will try to identify the good bacteria that maintain gut integrity with age as well as the bad bacteria that cause the gut to become leaky. They are also trying to understand how early in life some of these changes in the microbiota start occurring so that they could try to intervene before they are severe enough to alter immune function.
In the end, this research could lead to new strategies for manipulating the microbiome to improve intestinal health and decrease age-associated inflammation. "Since age-associated inflammation is linked to so many aspects of unhealthy aging, we predict that these strategies could help keep us healthy, active, and independent as we age," Bowdish says.
Materials provided by Cell Press. Note: Content may be edited for style and length.
(18-07-2018) Keep your heart healthy by eating more arugula, spinach, and beets
(18-07-2018) Prescrizioni inappropriate, lo studio: troppi antibiotici in gravidanza
(18-07-2018) Psoriasis linked to gut health: Leaky gut could be caused by microbiome composition
(18-07-2018) L'emicrania potrebbe essere scatenata dagli estrogeni anche negli uomini
(17-07-2018) Both depression and obesity are on the rise – coincidence? These conditions are linked in many ways
(17-07-2018) Assunzione alcolici aumenta la pressione sanguigna, ecco le categorie più a rischio
(17-07-2018) Tomato extracts KILL stomach cancer cells, new study shows
(17-07-2018) L'allergia alla penicillina causa un aumento del rischio di infezioni resistenti
(16-07-2018) Garlic is good for your heart; it lowers your blood pressure
(16-07-2018) Diabete, in situazione di stress aumenta rischio di attacco cardiaco e ictus
(16-07-2018) High-dose ω-3 Fatty Acid Plus Vitamin D3 Supplementation Affects Clinical Symptoms and Metabolic Status of Patients with Multiple Sclerosis: A Randomized Controlled Clinical Trial.
(16-07-2018) Malattie psoriasiche, la dieta può variare la gravità di presentazione nei pazienti in sovrappeso
(15-07-2018) Are you familiar with these 20 herbs that can be used as medicine?
(15-07-2018) La dieta migliore
(15-07-2018) Genome-wide association meta-analysis highlights light-induced signaling as a driver for refractive error
(15-07-2018) Miopia, individuati 161 geni che la favoriscono
(14-07-2018) Carotenoids in human nutrition and health
(14-07-2018) L’importanza dei carotenoidi
(14-07-2018) Tips for reducing your risk of breast cancer at any age
(14-07-2018) Tatuaggi, nelle persone immunodepresse possibili gravi complicanze
(13-07-2018) Low amounts of testosterone put men at risk of chronic diseases, even if they’re young
(13-07-2018) Disbiosi intestinale e rischio cardiovascolare: presentata una consensus
(13-07-2018) Cut your risk for liver cancer by HALF by just increasing your vitamin D levels
(13-07-2018) I disturbi correlati allo stress sono associati allo sviluppo di malattie autoimmuni successive
(12-07-2018) Follow these simple tips to minimize your exposure to “obesogens” – everyday chemicals that make you fat
(12-07-2018) La combinazione di solventi organici e predisposizione genetica aumenta il rischio di sclerosi multipla
(12-07-2018) Brisk walking for 3 hours a week can reduce your risk of heart disease
(12-07-2018) Il diuretico Idroclorotiazide può aumentare il rischio di melanoma
(11-07-2018) Alzheimer’s disease and Dementia are two entirely different things
(11-07-2018) Il microbiota intestinale può aiutare a predire le persone a più alto rischio di epatocarcinoma
(11-07-2018) Eat more Swiss chard to enhance endurance and lower your blood pressure
(11-07-2018) Bere una o più tazze di tè caldo riduce il rischio glaucoma del 74%
(10-07-2018) CONFIRMED: Antidepressants and other drugs cause dementia
(10-07-2018) La privazione del sonno associata a un maggiore propensione a ingerire più cibo
(10-07-2018) Acupuncture can relieve neck pain, new study confirms
(10-07-2018) I pomodori e le mele possono rallentare il declino della funzione polmonare. Benefici nella BPCO ?
(09-07-2018) Heavy menstruation could be a symptom of an underlying condition that causes fertility problems
(09-07-2018) Farmaci antibatterici: rischio di aritmie potenzialmente fatali con Azitromicina
(09-07-2018) Children and pre-teens who lack sleep are 58% more likely to become obese as adults
(09-07-2018) Associazione tra peso e mortalità negli adulti con diabete mellito
(08-07-2018) 10 Yummy, brain-boosting foods that prevent neurocognitive decline
(08-07-2018) Il brutto tempo influenza l’umore
(08-07-2018) Autoimmune disease doesn’t have to take over your life
(08-07-2018) Rughe? Frutta e verdura fresca meglio di creme
(07-07-2018) Study: Consuming foods rich in omega-3 fatty acids cuts your risk of death by 33%
(07-07-2018) Asma. L’uso di antibiotici prolunga la degenza in ospedale
(07-07-2018) BUSTED: 8 sleep myths that actually make you more tired
(07-07-2018) IL RUOLO DELLA VITAMINA D NEL CONTROLLO GLICEMICO
"L'informazione presente nel sito serve a migliorare, e non a sostituire, il rapporto medico-paziente."
Per coloro che hanno problemi di salute si consiglia di consultare sempre il proprio medico curante.
Ricette a zona
Tabella composizione corporea
ABC della nutrizione