Hexokinase 1 cellular localization regulates the metabolic fate of glucose.

The product of hexokinase (HK) enzymes, glucose-6-phosphate, can be metabolized through glycolysis or directed to alternative metabolic routes, such as the pentose phosphate pathway (PPP) to generate anabolic intermediates. HK1 contains an N-terminal mitochondrial binding domain (MBD), but its physiologic significance remains unclear. To elucidate the effect of HK1 mitochondrial dissociation on cellular metabolism, we generated mice lacking the HK1 MBD (ΔE1HK1). These mice produced a hyper-inflammatory response when challenged with lipopolysaccharide. Additionally, there was decreased glucose flux below the level of GAPDH and increased upstream flux through the PPP. The glycolytic block below GAPDH is mediated by the binding of cytosolic HK1 with S100A8/A9, resulting in GAPDH nitrosylation through iNOS. Additionally, human and mouse macrophages from conditions of low-grade inflammation, such as aging and diabetes, displayed increased cytosolic HK1 and reduced GAPDH activity. Our data indicate that HK1 mitochondrial binding alters glucose metabolism through regulation of GAPDH.

Health Status in Heart Failure and Cancer: Analysis of the Medicare Health Outcomes Survey 2016-2020.

BACKGROUND: People with heart failure (HF) and cancer experience impaired physical and mental health status. However, health-related quality of life (HRQOL) has not been directly compared between these conditions in a contemporary population of older people. OBJECTIVES: The authors sought to compare HRQOL in people with HF vs those with lung, colorectal, breast, and prostate cancers. METHODS: The authors performed a pooled analysis of Medicare Health Outcomes Survey data from 2016 to 2020 in participants ≥65 years of age with a self-reported history of HF or active treatment for lung, colon, breast, or prostate cancer. They used the Veterans RAND-12 physical component score (PCS) and mental component score (MCS), which range from 0-100 with a mean score of 50 (based on the U.S. general population) and an SD of 10. The authors used pairwise Student's t-tests to evaluate for differences in PCS and MCS between groups. RESULTS: Among participants with HF (n = 71,025; 54% female, 16% Black), mean PCS was 29.5 and mean MCS 47.9. Mean PCS was lower in people with HF compared with lung (31.2; n = 4,165), colorectal (35.6; n = 4,270), breast (37.7; n = 14,542), and prostate (39.6; n = 17,670) cancer (all P < 0.001). Participants with HF had a significantly lower mean MCS than those with lung (31.2), colon (50.0), breast (52.0), and prostate (53.0) cancer (all P < 0.001). CONCLUSIONS: People with HF experience worse HRQOL than those with cancer actively receiving treatment. The pervasiveness of low HRQOL in HF underscores the need to implement evidence-based interventions that target physical and mental health status and scale multidisciplinary clinics.