Summary: A new study from Virginia Tech reveals a healthy bacteria found in yogurt could reduce some lupus symptoms. The study expands on earlier work from the researchers, noting a lack of Lactobacillus in both mice and humans with lupus.
Source: Virginia Tech.
Researchers at the Virginia-Maryland College of Veterinary Medicine at Virginia Tech have released findings that explain how a type of healthy bacteria in yogurt and other dairy products might reduce disease symptoms in certain patients with lupus.
Xin Luo, assistant professor of immunology in the Department of Biomedical Sciences and Pathobiology, and her colleagues expanded upon earlier research linking a lack of Lactobacillus, which produces lactic acid and is an important part of gut microbiota in both humans and mice, and autoimmune diseases such as lupus. The new research describes the mechanism behind this association.
“In our 2014 paper, we found that mice with lupus had decreased amounts of Lactobacillus, which led to our hypothesis that adding this bacteria could ameliorate disease symptoms,” said Luo, who added that she and her colleagues also found that the mice had a “leaky gut,” a condition that affects the intestinal lining. “Probiotics, such as Lactobacillus, work by patching up and reversing the leaky gut.”
Lupus is an autoimmune disease that can cause chronic fatigue, joint pain, rash, fever, renal failure, and even death. It affects an estimated 3 million people in the United States. Luo’s recent study deals with lupus nephritis, or inflammation of the kidney that is caused by lupus.
According to the National Resource Center on Lupus, lupus nephritis usually develops within the first five years after lupus symptoms start, and as many as 40 percent of all people with lupus, and up to two-thirds of children with the disease, will develop kidney complications.
“In addition, we found that the addition of Lactobacillus to the diet only affected female mice and not males,” said Luo, who explained that lupus is 10 times more prevalent in females than in males. “We think that testosterone is suppressing the effect of the healthy bacteria. Before our study, researchers had never looked at male hormones suppressing the probiotic effect before.”
The research team included Qinghui Mu, a Ph.D. student in the biomedical and veterinary sciences program and recent recipient of a prestigious American Association of Immunologists Careers in Immunology Fellowship, and S. Ansar Ahmed, professor of immunology and associate dean of research and graduate studies at the veterinary college. Ahmed is also one of the leading authorities on the effect of hormones on lupus and other autoimmune disorders.
Although the research was limited to mice with lupus and kidney inflammation, and more work would need to be done to determine whether Lactobacillus has the same effect in humans, Luo emphasized that yogurt and probiotic supplements are considered safe.
“If a lupus patient is female and also has kidney inflammation, there would be no harm in adding yogurt or a probiotic supplement to the diet,” she said.
Now that researchers have identified the “good” bacteria that affects the severity of lupus, they hope to turn their attention to other areas of research.
“The next question is, ‘Are there bad bacteria that can be detrimental to the disease?’ ” Luo asked. “If that can be found, we can target the bad bacteria and remove them to ameliorate disease symptoms.”
Source: Alison Elward – Virginia Tech
Image Source: NeuroscienceNews.com image is credited to Luo et al./Microbiome.
Original Research: Full open access research for “Control of lupus nephritis by changes of gut microbiota” by Qinghui Mu, Husen Zhang, Xiaofeng Liao, Kaisen Lin, Hualan Liu, Michael R. Edwards, S. Ansar Ahmed, Ruoxi Yuan, Liwu Li, Thomas E. Cecere, David B. Branson, Jay L. Kirby, Poorna Goswami, Caroline M. Leeth, Kaitlin A. Read, Kenneth J. Oestreich, Miranda D. Vieson, Christopher M. Reilly and Xin M. Luo in Microbiome. Published online July 11 2017 doi:10.1186/s40168-017-0300-8
Control of lupus nephritis by changes of gut microbiota
Systemic lupus erythematosus, characterized by persistent inflammation, is a complex autoimmune disorder with no known cure. Immunosuppressants used in treatment put patients at a higher risk of infections. New knowledge of disease modulators, such as symbiotic bacteria, can enable fine-tuning of parts of the immune system, rather than suppressing it altogether.
Dysbiosis of gut microbiota promotes autoimmune disorders that damage extraintestinal organs. Here we report a role of gut microbiota in the pathogenesis of renal dysfunction in lupus. Using a classical model of lupus nephritis, MRL/lpr, we found a marked depletion of Lactobacillales in the gut microbiota. Increasing Lactobacillales in the gut improved renal function of these mice and prolonged their survival. We used a mixture of 5 Lactobacillus strains (Lactobacillus oris, Lactobacillus rhamnosus, Lactobacillus reuteri, Lactobacillus johnsonii, and Lactobacillus gasseri), but L. reuteri and an uncultured Lactobacillus sp. accounted for most of the observed effects. Further studies revealed that MRL/lpr mice possessed a “leaky” gut, which was reversed by increased Lactobacillus colonization. Lactobacillus treatment contributed to an anti-inflammatory environment by decreasing IL-6 and increasing IL-10 production in the gut. In the circulation, Lactobacillus treatment increased IL-10 and decreased IgG2a that is considered to be a major immune deposit in the kidney of MRL/lpr mice. Inside the kidney, Lactobacillus treatment also skewed the Treg-Th17 balance towards a Treg phenotype. These beneficial effects were present in female and castrated male mice, but not in intact males, suggesting that the gut microbiota controls lupus nephritis in a sex hormone-dependent manner.
This work demonstrates essential mechanisms on how changes of the gut microbiota regulate lupus-associated immune responses in mice. Future studies are warranted to determine if these results can be replicated in human subjects.
“Control of lupus nephritis by changes of gut microbiota” by Qinghui Mu†, Husen Zhang†, Xiaofeng Liao, Kaisen Lin, Hualan Liu, Michael R. Edwards, S. Ansar Ahmed, Ruoxi Yuan, Liwu Li, Thomas E. Cecere, David B. Branson, Jay L. Kirby, Poorna Goswami, Caroline M. Leeth, Kaitlin A. Read, Kenneth J. Oestreich, Miranda D. Vieson, Christopher M. Reilly and Xin M. Luo in Microbiome. Published online July 11 2017 doi:10.1186/s40168-017-0300-8