From cradle to grave, our gut is our most important physiological connection to the microbiome.  While significant progress has been made to understand the development of this complex community early in life, it is only recently that researchers have begun to understand its deterioration later in life.  Scientists are now recognizing the important influence the microbiome may have on the aging process and many end-of-life diseases.  Through continued research we may someday be able to manipulate the microbiome to reduce risk of certain geriatric diseases, and even use microbiome-targeted therapies to live longer, more active lives.

Research has shown that the microbiome loses diversity and becomes more fragile in the elderly, and it is now being associated with age-related constipation and low-level chronic inflammation (known as ‘inflammaging’) (1).  Importantly though, it appears that diet is primarily responsible for these microbiome shifts, and modulating the diet may help restore the microbiome and extend our sprightly years (2).

Beyond general frailty, the microbiome has been associated with diseases that tend to afflict the elderly, such as Alzheimer’s (3) and Parkinson’s (4).  This relationship is unsurprising as many of these idiopathic diseases are thought to have environmental risk factors, and the microbiome is among the most important connections we have to our environment.

Two important papers have recently been published regarding the microbiome and aging.  The first, by the prominent microbiome scientist Martin Blaser from New York University, speculates on how the microbiome could be aging us, rather than us aging independent of the microbiome (5).  The other, written by Morgan Langille from Dalhousie University in Halifax, Canada, uses a mouse model to investigate possible mechanisms behind microbiome-associated frailties (6).

See below for links to the short summaries of these papers, originally posted on the American Microbiome Institute blog:

The Blaser hypothesis: The microbiome is programmed to kill us

Changes in the microbiome may affect how we age

References:

(1) Candela M, Biagi E, Brigidi P, O’Toole PW, De Vos WM. (2014.) Maintenance of a healthy trajectory of the intestinal microbiome during aging: a dietary approach. Mech. Ageing Dev. 136-137:70–5

(2) Claesson MJ, Jeffery IB, Conde S, Power SE, O’Connor EM, Cusack S, Harris HMB, Coakley M, Lakshminarayanan B, O’Sullivan O, Fitzgerald GF, Deane J, O’Connor M, Harnedy N, O’Connor K, O’Mahony D, van Sinderen D, Wallace M, Brennan L, Stanton C, Marchesi JR, Fitzgerald AP, Shanahan F, Hill C, Ross RP, O’Toole PW. (2012) Gut microbiota composition correlates with diet and health in the elderly. Nature 488:178–84

(3) Allen SJ, Shoemaker DK. (2015) The Microbiome and Disease: Reviewing the Links between the Oral Microbiome, Aging, and Alzheimer’s Disease. J. Alzheimer’s Dis. 43:725–738

(4) Scheperjans F, Aho V, Pereira PAB, Koskinen K, Paulin L, Pekkonen E, Haapaniemi E, Kaakkola S, Eerola-Rautio J, Pohja M, Kinnunen E, Murros K, Auvinen P. (2014) Gut microbiota are related to Parkinson’s disease and clinical phenotype. Mov. Disord. 29 Suppl 1 :1548

(5) Blaser MJ, Webb GF. (2014) Host Demise as a Beneficial Function of Indigenous Microbiota in Human Hosts. MBio 5:e02262–14–e02262–14

(6) Langille M, Meehan CJ, Koenig JE, Dhanani AS, Rose RA, Howlett SE, Beiko RG. (2014) Microbial shifts in the aging mouse gut. Microbiome 2:50