Human Microbiome and its Association With Health and Diseases

Human microbiota are distinct communities of microorganisms that resides at different body niches. Exploration of the human microbiome has become a reality due to the availability of powerful metagenomics and metatranscriptomic analysis technologies. Recent advances in sequencing and bioinformatics over the past decade help provide a deep insight into the nature of the host-microbial interactions and identification of potential deriver genes and pathways associated with human health, well-being, and predisposition to different diseases. In the present review, we outline recent studies devoted to elucidate the possible link between the microbiota and various type of diseases. The present review also highlights the potential utilization of microbiota as a potential therapeutic option to treat a wide array of human diseases.

Humans are viewed as composites of human and microbial cells. Human microbiota are complex and dynamic microbial communities composed mainly of bacteria, but also includes protozoa, archaea, viruses, and fungi that resides in and on different body niches such as oral cavity, throat, esophagus, stomach, colon, urogenital tract, respiratory tract, and skin. The number of microbial cells inhabiting human body is estimated to exceed the H.sapiens cells by 10-fold and estimated at 350 trillion microbial cells.

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Microbiome-host interactions. Schematic representation showing the perplexed microbial-host
interactions due to different triggering factors on microbiota and their genetic material constitute;
the human microbiome.

Source: Wiley

Chronic Fatigue Syndrome: Could Altered Gut Bacteria be a Cause?

What causes chronic fatigue syndrome? The answer to this question continues to baffle researchers, so much so that some have even questioned whether the condition exists. Now, a new study by researchers from Cornell University in Ithaca, NY, may have shed light on a biological cause, after finding that patients with chronic fatigue have an altered gut microbiome.

Senior author Maureen Hanson, of the Departments of Molecular Biology and Genetics and Microbiology at Cornell, and colleagues publish their findings in the journal Microbiome.

Also referred to as myalgic encephalomyelitis (ME), chronic fatigue syndrome (CFS) is a condition characterized by extreme fatigue that does not improve with rest.

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Researchers found that people with CFS have abnormalities in their gut microbiome.

Source: medicalnewstoday

Breast milk hormones found to impact bacterial development in infants' guts

Intestinal microbiome of children born to obese mothers significantly different from those born to mothers of healthy weight

A new study finds that hormones in breast milk may impact the development of healthy bacteria in infants' guts, potentially protecting them from intestinal inflammation, obesity and other diseases later in life.

The study, published Monday in the American Journal of Clinical Nutrition, examines the role of human milk hormones in the development of infants' microbiome, a bacterial ecosystem in the digestive system that contributes to multiple facets of health.

"This is the first study of its kind to suggest that hormones in human milk may play an important role in shaping a healthy infant microbiome," said Bridget Young, co-first author and assistant professor of pediatric nutrition at CU Anschutz. "We've known for a long time that breast milk contributes to infant intestinal maturation and healthy growth. This study suggests that hormones in milk may be partly responsible for this positive impact through interactions with the infant's developing microbiome."

Researchers found that levels of insulin and leptin in the breast milk were positively associated with greater microbial diversity and families of bacteria in the infants' stool.

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A new study examined the role of human milk hormones in the development of infants' microbiome

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Microbes and Cancer.

Understanding cancer’s relationship with the human microbiome could transform immune-modulating therapies.

In 2013, two independent teams of scientists, one in Maryland and one in France, made a surprising observation: both germ-free mice and mice treated with a heavy dose of antibiotics responded poorly to a variety of cancer therapies typically effective in rodents. The Maryland team, led by Romina Goldszmid and Giorgio Trinchieri of the National Cancer Institute, showed that both an investigational immunotherapy and an approved platinum chemotherapy shrank a variety of implanted tumor types and improved survival to a far greater extent in mice with intact microbiomes. The French group, led by INSERM’s Laurence Zitvogel, got similar results when testing the long-standing chemotherapeutic agent cyclophosphamide in cancer-implanted mice, as well as in mice genetically engineered to develop tumors of the lung.

The findings incited a flurry of research and speculation about how gut microbes contribute to cancer cell death, even in tumors far from the gastrointestinal tract. The most logical link between the microbiome and cancer is the immune system. Resident microbes can either dial up inflammation or tamp it down, and can modulate immune cells’ vigilance for invaders. Not only does the immune system appear to be at the root of how the microbiome interacts with cancer therapies, it also appears to mediate how our bacteria, fungi, and viruses influence cancer development in the first place.

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Source: © Istock/Kateja_FN/Frank Ramspott

Metabolic Diseases Could be Promoted by 'Unhealthy' Microbiomes.

Trillions of bacteria surround us, permeate us, and bind our bodies together. They affect our immune systems and our brains, they shift and change with our diet, and some researchers suspect that these microbial multitudes may be an important link between our modern lifestyle and ongoing epidemics of diseases such as asthma, obesity, and diabetes.

Leading microbiome researchers recently came to UC San Francisco to share the newest insights about how improving our relationship with our bodies’ microbial ecosystems could be the next big breakthrough in treating metabolic disease. One major theme of the symposium – hosted by theUniversity of California Sugar, Stress, Environment, and Weight (SSEW) Center – was the question of whether the troubling modern epidemic of metabolic disease may arise in part because our civilization has not been kind to our microbes.

“In Western industrialized nations, we have dramatically changed our interaction with microbes in last several decades,” said Susan Lynch, PhD, who studies links between the microbiome and chronic inflammatory diseases at UCSF. “Particularly in urbanized areas, we have less contact with the soil and with animals. We have changed our diets dramatically and waged war on our microbes with antibiotics.”

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Source: ucsf.edu