Host Metabolic Changes during Mycobacterium Tuberculosis Infection Cause Insulin Resistance in Adult Mice. 2022

Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
Center for Discovery and Innovation, Hackensack University Medical Center, Hackensack, NJ 07110, USA.

Tuberculosis (TB) is a highly infectious bacterial disease that primarily attacks the lungs. TB is manifested either as latent TB infection (LTBI) or active TB disease, the latter posing a greater threat to life. The risk of developing active TB disease from LTBI is three times higher in individuals with type 2 diabetes mellitus (T2DM). The association between TB and T2DM is becoming more prominent as T2DM is rapidly increasing in settings where TB is endemic. T2DM is a chronic metabolic disorder characterized by elevated blood glucose, insulin resistance, and relative insulin deficiency. Insulin resistance and stress-induced hyperglycemia have been shown to be increased by TB and to return to normal upon treatment. Previously, we demonstrated that adipocytes (or fat tissue) regulate pulmonary pathology, inflammation, and Mycobacterium tuberculosis (Mtb) load in a murine model of TB. Metabolic disturbances of adipose tissue and/or adipocyte dysfunction contribute to the pathogenesis of T2DM. Thus, pathological adipocytes not only regulate pulmonary pathology, but also increase the risk for T2DM during TB infection. However, the cellular and molecular mechanisms driving the interaction between hyperglycemia, T2DM and TB remain poorly understood. Here, we report the impact of Mtb infection on the development of insulin resistance in mice fed on a regular diet (RD) versus high-fat diet (HFD) and, conversely, the effect of hyperglycemia on pulmonary pathogenesis in juvenile and adult mouse models. Overall, our study demonstrated that Mtb persists in adipose tissue and that Mtb infection induces irregular adipocyte lipolysis and loss of fat cells via different pathways in RD- and HFD-fed mice. In RD-fed mice, the levels of TNFα and HSL (hormone sensitive lipase) play an important role whereas in HFD-fed mice, ATGL (adipose triglyceride lipase) plays a major role in regulating adipocyte lipolysis and apoptosis during Mtb infection in adult mice. We also showed that Mtb infected adult mice that were fed an RD developed insulin resistance similar to infected adult mice that were overweight due to a HFD diet. Importantly, we found that a consequence of Mtb infection was increased lipid accumulation in the lungs, which altered cellular energy metabolism by inhibiting major energy signaling pathways such as insulin, AMPK and mToR. Thus, an altered balance between lipid metabolism and glucose metabolism in adipose tissue and other organs including the lungs may be an important component of the link between Mtb infection and subsequent metabolic syndrome.

UI MeSH Term Description Entries

Related Publications

Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
May 2016, Tuberculosis (Edinburgh, Scotland),
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
December 2012, The Journal of infectious diseases,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
November 2018, Nature microbiology,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
February 2020, Pathogens (Basel, Switzerland),
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
November 2022, The Journal of experimental medicine,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
November 1991, Infection and immunity,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
May 2023, Nature microbiology,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
February 2021, Metabolites,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
September 2005, American journal of respiratory and critical care medicine,
Neelam Oswal, and Kezia Lizardo, and Dhanya Dhanyalayam, and Janeesh P Ayyappan, and Hariprasad Thangavel, and Scott K Heysell, and Jyothi F Nagajyothi
May 2008, Cell host & microbe,
Copied contents to your clipboard!