Related Experiment Video
Updated: May 24, 2026
06:59
Trabecular Bone Microarchitecture Evaluation in an Osteoporosis Mouse Model
Published on: September 8, 2023
The gut microbiota regulates bone mass in mice
Klara Sjögren1, Cecilia Engdahl, Petra Henning
1Centre for Bone and Arthritis Research, Institute of Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden. Klara.Sjogren@medic.gu.se.
Summary
The gut microbiota significantly impacts bone mass in mice. Introducing a normal gut microbiota to germ-free mice normalized their bone density, suggesting a link between gut bacteria and bone health.
Area of Science:
- Microbiology
- Immunology
- Bone Biology
Background:
- The gut microbiota influences host metabolism and immune system development.
- Its role in regulating bone mass is an emerging area of research.
Purpose of the Study:
- To investigate the gut microbiota's role in regulating bone mass in mice.
- To elucidate the underlying mechanisms involving immune status and osteoclast activity.
Main Methods:
- Comparison of bone mass in germ-free (GF) mice and conventionally raised (CONV-R) mice.
- Colonization of GF mice with a normal gut microbiota.
- Analysis of immune cell populations (CD4(+) T cells, osteoclast precursors) and inflammatory cytokine expression in bone and bone marrow.
Main Results:
- GF mice exhibited increased bone mass compared to CONV-R mice, with fewer osteoclasts.
- Colonization of GF mice normalized bone mass and immune cell frequencies.
- GF mice showed reduced expression of inflammatory cytokines in bone and bone marrow.
Conclusions:
- The gut microbiota is a key regulator of bone mass in mice.
- Altered immune status in bone, affecting osteoclast-mediated resorption, is a likely mechanism.
- The gut microbiota represents a potential therapeutic target for osteoporosis.
Related Concept Videos
01:18Functions of the Gut Microbiota
The gut microbiota includes trillions of microorganisms that colonize the human gastrointestinal tract, including bacteria, archaea, viruses, and fungi. This complex ecosystem plays a critical role in maintaining intestinal and systemic health. Most of these microbes inhabit the large intestine, establishing a relatively stable and diverse community that contributes to gut homeostasis through various metabolic, immunological, and protective mechanisms.Dominant bacterial phyla, such as...
01:40Bone Remodeling
Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
01:17Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
01:22Gut-Brain Axis
The gut–brain axis is a bidirectional communication system that connects the gastrointestinal tract and the brain. This interaction is mediated through multiple pathways, including the vagus nerve, hormonal signals, immune responses, and chemical messengers produced by gut microbes.Microbial Contributions to Brain FunctionGut microbiota contributes significantly to brain function by producing neuroactive compounds. These include neuroactive compounds that influence neurotransmitters such as...
01:27The Oral Microbiota
The oral microbiome includes a complex ecosystem comprising over 700 microbial species, identified through genomic sequencing and culture-based analyses to date. This community includes a core microbiome, found universally among individuals, and a variable component influenced by environmental factors such as diet, lifestyle, and host genetics. Site-specific conditions, including oxygen gradients, pH levels, and nutrient availability, determine the spatial distribution of these microorganisms...
01:29Bone Disorders
Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...