June 29, 2023 – Curtis Huttenhowerprofessor of computational biology and bioinformatics at the Harvard TH Chan School of Public Health, studies the role played by microbiota plays in health and disease. He most often focuses on the human gut, but his research has recently expanded to pets, including dogs and cats.
Q: What motivated you to study the gut microbiome of pets and how does it relate to human health?
A: Initially, I was excited about the opportunity to extend our human microbiome research to pets, as I have been a cat dad for decades and pet welfare is one of my passions. great personal passions. However, as we launched a few studies, I realized how much scientific opportunity there really is in pet microbiome research, both for the benefit of our four-legged friends and for ours.
First, everyone wants their pets to live forever, and our studies of their gut microbiome have the potential to improve animal health in a variety of ways. For example, chronic kidney disease is one of the most common age-related illnesses in cats. Since the microbiome can be an important source of kidney-damaging uremic toxins, we hope to avoid this risk factor with appropriately targeted measures. diets. Additionally, the research community has learned much in recent years about manipulating the human gut microbiome – discoveries that can be applied to promoting animal health. For example, the success of certain types of cancer treatment depends on the gut microbiome, as does recovery of antibiotics, which interfere with beneficial microbes in addition to pathogens. Additionally, adding the right beneficial microbes can improve the management of conditions such as inflammatory bowel disease.
Second, certain aspects of pets’ lifestyle make their gut microbiome inherently easier to study than that of humans. Many pets eat a monotonous, chemically controlled diet, which allows us to measure very precise interactions between long-term dietary exposures and microbial responses. In contrast, humans rarely eat the exact same thing twice, let alone the same perfectly controlled meal day after day. If we can use pets’ diets to understand how specific food components interact with their gut microbes to promote or prevent obesitywe can also use this information for human health.
Q: You work with Hill’s Pet Nutrition, a pet food company. Can you talk about the work you do together?
A: Hill’s operates a pet nutrition center with a unique setup that allows it to fine-tune the nutrient levels in its products and accommodate highly sophisticated microbiome research. At the center, approximately 450 dogs and 450 cats receive special attention from technicians dedicated enough to know the name and personality of each animal. The center has on-site medical care and food manufacturing, as well as a custom robotic system that automatically tracks the specific types and amounts of food consumed by each animal. The composition of each food is known at the time of manufacture and, upon release, so to speak, stool samples can be collected almost immediately, processed, frozen using an extremely well validated protocol and analyzed on site to detect microbial DNA. , metabolites, and more. Needless to say, this level of detail is impossible with studies done on humans.
With Hill’s experts, we are working on a range of studies in humans and pets that investigate the interactions between diet and the microbiome. In a study we did, we studied dogs that ate foods containing 12 different diets. fiber sources and compositions, for example, high or low in fiber, or corn starch or pea fiber. One of the most surprising results was that, despite fully controlled diets and a uniform living environment, differences in gut microbes in dogs still resulted in the production of very distinct chemicals via microbial fermentation during the digestion. Some dogs could ferment the same fiber more efficiently than another, simply because of different microbes that had taken up residence in their intestines.
These differences in gut microbial chemistry may help explain aspects of weight maintenance and health. aging in dogs as in humans, since the same microbial “personalization” also exists in humans. Most microbial fermentation products are good, in general, and so more efficient fermentation is probably beneficial. Our results are also consistent with several human diet studies we have published, which have shown that the extent to which high-fiber diets help prevent inflammation depends on what gut microbes people have. Likewise, we found that to what extent a Mediterranean diet improves heart health depends on the intestinal microbes present.
Our dietary studies expose a theme that has become important in recent microbiome research: that microbes are just little bags of chemicals, and they can perform truly remarkable metabolism. This helps explain why different people respond differently to the same diet, or why the same medication may work better in one person than another. We all carry very different bugs in our microbiomes – a much greater variation than among animals living in a shared environment – and these microbial differences mean that the types of chemistry that occur in our bodies can change subtly from one person to another. Determining exactly how microbes contribute to this chemistry can help improve drug dosing, personalized therapiesAnd Healthy eating guidelines.
Q: What are the broader public health implications of your work?
A: The connections between pet health and human health reflect the One Health initiative advanced by the WHO, CDC and other public health organizations, which focuses on the concept that humans, animals and Environmental health are all inextricably linked. For example, epidemiological studies have shown that infants exposed early to more furry animals and green spaces are at lower risk of developing immune and allergic diseases later in life. We have come to understand that some of these effects are due to the microbiome: acquiring the “right” microbes at the “right” time leads to better health throughout life. However, the opposite can also be true. Due to the greater use of antibiotics in veterinary medicine than in human medicine, microbes in an animal’s gut can become resistant to antibiotics. If these resistant microbes, or their genetic material, were transferred to an owner, they could potentially pose a health risk.
Along the same lines, we are working on another study in collaboration with the Nurses’ Health Study 3 And Growing up today study, which are managed by the Harvard Chan School and the Channing Division of Network Medicine at Brigham and Women’s Hospital. We compare the microbiomes of pets and their owners, with the aim of understanding which microbes can transfer between the two, how and what the consequences might be for immune or metabolic health. It will be exciting to discover the results of this new line of research, for the benefit of human and animal health.
– Jay Lau
