Long-Term Green Tea Supplementation Does Not Change the Human Gut Microbiota
http://journals.plos.org/plosone/art...l.pone.0153134
Abstract
How Green Tea Extract Could Help Protect Against Alzheimer’s
http://neurosciencenews.com/green-te...zheimers-7724/
http://journals.plos.org/plosone/art...l.pone.0153134
Abstract
Background
Green tea catechins may play a role in body weight regulation through interactions with the gut microbiota.
Aim
We examined whether green tea supplementation for 12 weeks induces changes in composition of the human gut microbiota.
Methods
58 Caucasian men and women were included in a randomized, placebo-controlled design. For 12 weeks, subjects consumed either green tea (>0.56 g/d epigallocatechin-gallate + 0.28 ∼ 0.45 g/d caffeine) or placebo capsules. Fecal samples were collected twice (baseline, vs. week 12) for analyses of total bacterial profiles by means of IS-profiling, a 16S-23S interspacer region-based profiling method.
Results
No significant changes between baseline and week 12 in subjects receiving green tea or placebo capsules, and no significant interactions between treatment (green tea or placebo) and time (baseline and week 12) were observed for body composition. Analysis of the fecal samples in subjects receiving green tea and placebo showed similar bacterial diversity and community structures, indicating there were no significant changes in bacterial diversity between baseline and week 12 in subjects receiving green tea capsules or in subjects receiving placebo capsules. No significant interactions were observed between treatment (green tea or placebo) and time (baseline and week 12) for the gut microbial diversity. Although, there were no significant differences between normal weight and overweight subjects in response to green tea, we did observe a reduced bacterial alpha diversity in overweight as compared to normal weight subjects (p = 0.002).
Conclusion
Green tea supplementation for 12 weeks did not have a significant effect on composition of the gut microbiota.
Green tea catechins may play a role in body weight regulation through interactions with the gut microbiota.
Aim
We examined whether green tea supplementation for 12 weeks induces changes in composition of the human gut microbiota.
Methods
58 Caucasian men and women were included in a randomized, placebo-controlled design. For 12 weeks, subjects consumed either green tea (>0.56 g/d epigallocatechin-gallate + 0.28 ∼ 0.45 g/d caffeine) or placebo capsules. Fecal samples were collected twice (baseline, vs. week 12) for analyses of total bacterial profiles by means of IS-profiling, a 16S-23S interspacer region-based profiling method.
Results
No significant changes between baseline and week 12 in subjects receiving green tea or placebo capsules, and no significant interactions between treatment (green tea or placebo) and time (baseline and week 12) were observed for body composition. Analysis of the fecal samples in subjects receiving green tea and placebo showed similar bacterial diversity and community structures, indicating there were no significant changes in bacterial diversity between baseline and week 12 in subjects receiving green tea capsules or in subjects receiving placebo capsules. No significant interactions were observed between treatment (green tea or placebo) and time (baseline and week 12) for the gut microbial diversity. Although, there were no significant differences between normal weight and overweight subjects in response to green tea, we did observe a reduced bacterial alpha diversity in overweight as compared to normal weight subjects (p = 0.002).
Conclusion
Green tea supplementation for 12 weeks did not have a significant effect on composition of the gut microbiota.
http://neurosciencenews.com/green-te...zheimers-7724/
Research from McMaster University is shedding new light on those underlying mechanisms. Preclinical evidence suggests that the green tea compound known as EGCG interferes with the formation of toxic assemblies (oligomers), one of the prime suspects in the early steps of the molecular cascade that leads to cognitive decline in Alzheimer’s patients.
“At the molecular level, we believe EGCG coats toxic oligomers and changes their ability to grow and interact with healthy cells,” explains Giuseppe Melacini, lead author and a professor in the Departments of Chemistry and Chemical Biology as well as of Biochemistry and Biomedical Sciences at McMaster, who has worked on Alzheimer’s-related research for 15 years.
The findings, which are the results of a decade of advancements in nuclear magnetic resonance (NMR) methodology and are featured in the cover page of the Journal of the American Chemical Society, could lead to new therapies and further drug discovery, say researchers.
Despite decades of research, the causes of Alzheimer’s remain not fully understood, and treatment options are limited. According to the latest census numbers, seniors living in Canada now outnumber children, dramatically increasing the need for effective drugs and prevention. By some estimates, the number of Canadians with dementia is expected to rise to 937,000 by the year 2031, an increase of 66 per cent compared to current numbers.
“We all know that currently there is no cure for Alzheimer’s once symptoms emerge, so our best hope is early intervention. That could mean using green tea extracts or their derivatives early on, say 15 to 25 years before any symptoms ever set in” says Melacini.
“At the molecular level, we believe EGCG coats toxic oligomers and changes their ability to grow and interact with healthy cells,” explains Giuseppe Melacini, lead author and a professor in the Departments of Chemistry and Chemical Biology as well as of Biochemistry and Biomedical Sciences at McMaster, who has worked on Alzheimer’s-related research for 15 years.
The findings, which are the results of a decade of advancements in nuclear magnetic resonance (NMR) methodology and are featured in the cover page of the Journal of the American Chemical Society, could lead to new therapies and further drug discovery, say researchers.
Despite decades of research, the causes of Alzheimer’s remain not fully understood, and treatment options are limited. According to the latest census numbers, seniors living in Canada now outnumber children, dramatically increasing the need for effective drugs and prevention. By some estimates, the number of Canadians with dementia is expected to rise to 937,000 by the year 2031, an increase of 66 per cent compared to current numbers.
“We all know that currently there is no cure for Alzheimer’s once symptoms emerge, so our best hope is early intervention. That could mean using green tea extracts or their derivatives early on, say 15 to 25 years before any symptoms ever set in” says Melacini.
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