Are noncontageous diseases contangeous?
We're used to thinking of conditions like obesity, heart disease, diabetes and cancer as being noncontageous. But increasing evidence from rodent models and from demographic studies in humans suggest a role for gut bacteria that can be shared between individuals. In the human studies, confounding factors like diet and lifestyle make the magnitude of the postulated effects unclear.
I remember when peptic ulcers were treated with a bland diet and were blamed on type A personalities. Now we know that gut infection with Helicobactor pylori explains most cases of peptic ulcers (which may progress to stomach cancer). There is also good evidence that gum disease can result in heart disease, as mouth bacteria can enter the circulation.
With regard to cardiovascular disease and the gut microbiome:
"These modified postulates can be applied to CVD (heart attacks and strokes), the most prevalent NCD worldwide. There are strong correlations with the prevalence of particular gut microbiota that encode the enzyme choline trimethylamine (TMA)–lyase (CutC) that metabolizes phosphocholine and carnitine (from red meat) into TMA, which then undergoes hepatic oxidation into trimethylamine oxide (TMAO) (11). The concentration of TMAO in the blood is a strong predictor of CVD, with higher prevalence of disease associated with the presence of CutC-encoding gut microbes (12). Germ-free animals do not acquire CVD, even if on a choline-rich diet, and vegans and vegetarians have lower CVD rates than meat eaters (13). If CutC is inhibited in animal models, CVD does not occur. Moreover, human gut microbes encoding CutC can be transplanted into animals, leading to CVD phenotypes (14). Research examining spousal or community rates of CVD have so far only examined environmental effects (e.g., smoking, obesity, and alcohol). These may alter the gut microbiota composition, and so further research is warranted to examine whether microbial transmission is also involved."
https://science.sciencemag.org/content/367/6475/250.full
I remember when peptic ulcers were treated with a bland diet and were blamed on type A personalities. Now we know that gut infection with Helicobactor pylori explains most cases of peptic ulcers (which may progress to stomach cancer). There is also good evidence that gum disease can result in heart disease, as mouth bacteria can enter the circulation.
With regard to cardiovascular disease and the gut microbiome:
"These modified postulates can be applied to CVD (heart attacks and strokes), the most prevalent NCD worldwide. There are strong correlations with the prevalence of particular gut microbiota that encode the enzyme choline trimethylamine (TMA)–lyase (CutC) that metabolizes phosphocholine and carnitine (from red meat) into TMA, which then undergoes hepatic oxidation into trimethylamine oxide (TMAO) (11). The concentration of TMAO in the blood is a strong predictor of CVD, with higher prevalence of disease associated with the presence of CutC-encoding gut microbes (12). Germ-free animals do not acquire CVD, even if on a choline-rich diet, and vegans and vegetarians have lower CVD rates than meat eaters (13). If CutC is inhibited in animal models, CVD does not occur. Moreover, human gut microbes encoding CutC can be transplanted into animals, leading to CVD phenotypes (14). Research examining spousal or community rates of CVD have so far only examined environmental effects (e.g., smoking, obesity, and alcohol). These may alter the gut microbiota composition, and so further research is warranted to examine whether microbial transmission is also involved."
https://science.sciencemag.org/content/367/6475/250.full
Comments
Post a Comment