New research group: muscle growth and metabolic health

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When the tissue of skeletal muscles shrinks, whether as a result of aging or serious illness, and muscle mass decreases, we speak of muscular atrophy. In the case of muscular hypertrophy, by contrast, musculature grows as a result of increased exercise such as physical work or muscle training. The different effects of the two phenomena on metabolic health are at the heart of the work of the HyperMet research group, which has been awarded funding of 4.5 million euros by the German Research Foundation (DFG) to pursue its research over the coming years. Professor Hanna Taipaleenmäki from the Institute of Musculoskeletal Medicine at LMU University Hospital is deputy spokesperson of the project, which is headed by Professor Henning Wackerhage from TU Munich. Researchers from Helmholtz Munich and TU Braunschweig are also involved.

In view of an aging and sedentary society, the relevance of this topic is obvious: While muscular atrophy has overwhelmingly negative health effects, muscular hypertrophy is associated with fat loss, better regulation of blood sugar levels, higher bone mineral density, and positive effects in cancer patients. In HyperMet, the researchers are investigating whether shrinking or growing muscles release metabolic products that respectively lead to a disruption of metabolism or improved metabolic health in other tissues.

Projects at LMU

The research group consists of nine projects in total, two of which are being carried out at LMU:

In the HyperBone project, Hanna Taipaleenmäki is studying how muscular hypertrophy and atrophy affect bone metabolism and bone marrow fat.

Skeletal muscles and bones are regulated by certain messenger molecules, and there are indications that muscles influence bone metabolism. For example, muscular atrophy caused by immobilization or glucocorticoids is associated with loss of bone mass and strength, whereas testosterone causes muscular hypertrophy and increases bone mass. Conversely, the fat content of bone marrow is frequently higher in the case of muscle and bone loss and lower in the case of muscular hypertrophy. In her project, Taipaleenmäki will employ advanced methods of metabolic research to investigate the metabolic connections between muscular, bone, and bone marrow fat and explore the hypothesis that the large bioenergetic demands of the locomotor system influence systemic metabolism. Her results could be valuable, among other things, for our understanding of diseases like osteoporosis.

In the HyperPig project meanwhile, Professor Eckhard Wolf and Arne Hinrichs (Center for Innovative Medical Models) are using pig models to investigate how changes in body composition toward less fat and more muscle affect metabolic health.

Wolf and Hinrichs are experts in the generation and characterization of genetically modified or diet-induced pig models. In their project, they will utilize modern metabolic research methods to investigate the genetic background and possible catalysts of muscular hypertrophy and generate pig models where this effect is particularly pronounced. The advanced metabolic research methods available through the HyperMet consortium, such as flux analyses, will be employed in a genetically modified pig model for the first time.