EXPRESS: Effectiveness of HMG-CoA reductase inhibitors on inflammation and metabolic markers in the US-Mexico border Hispanic population.

HMG-CoA reductase inhibitors (statins) are commonly used for dyslipidemia management to reduce the risk of cardiovascular disease (CVD). High-sensitivity C-reactive protein (hs-CRP) is an emerging systematic low-grade inflammatory marker associated with atherosclerotic CVD development. Despite racial/ethnic disparities in the use and response of statins and the anti-inflammatory effects of statins, the effectiveness of statins on inflammation and metabolic markers is unknown among Hispanics. We performed a retrospective cohort study using 150 adult patients scheduled for an annual physical exam at a family medicine clinic between January 1, 2021, and December 31, 2021. Effect size with a 95% confidence interval (CI) was estimated using adjusted regression analyses. Among 150 patients, 52 (34.67%) received statins. Patients who received statins had significantly reduced median hs-CRP (1.9 vs. 3.2, p=0.007), mean low-density lipoprotein (LDL-C) (101.18 vs. 124.6, p<0.001), and total cholesterol (172.6 vs. 194.5, p<0.001) concentrations compared to those who did not receive statins. In the propensity-scores matched analysis, lower concentrations of log-transformed hs-CRP (regression coefficient [RC], -0.48; 95%CI: -0.89, -0.07), LDL-C (RC, -19.57; 95%CI: -33.04, -6.1), and total cholesterol (RC, -23.47; 95%CI: -38.96, -7.98) were associated with statin use. In addition, hepatic steatosis (adjusted relative risk [aRR]=0.25; 95%CI: 0.08, 0.78, p= 0.017) was significantly lower among patients with the use of statins. Our study suggests that HMG-CoA reductase inhibitors may help reduce inflammation among Hispanic patients with dyslipidemia and hypertension. These findings have useful implications for preventing risk and disparities associated with cardiovascular and other inflammatory-induced diseases among the fastest-growing US Hispanic minorities.

Electron transport chain inhibition increases cellular dependence on purine transport and salvage.

Mitochondria house many metabolic pathways required for homeostasis and growth. To explore how human cells respond to mitochondrial dysfunction, we performed metabolomics in fibroblasts from patients with various mitochondrial disorders and cancer cells with electron transport chain (ETC) blockade. These analyses revealed extensive perturbations in purine metabolism, and stable isotope tracing demonstrated that ETC defects suppress de novo purine synthesis while enhancing purine salvage. In human lung cancer, tumors with markers of low oxidative mitochondrial metabolism exhibit enhanced expression of the salvage enzyme hypoxanthine phosphoribosyl transferase 1 (HPRT1) and high levels of the HPRT1 product inosine monophosphate. Mechanistically, ETC blockade activates the pentose phosphate pathway, providing phosphoribosyl diphosphate to drive purine salvage supplied by uptake of extracellular bases. Blocking HPRT1 sensitizes cancer cells to ETC inhibition. These findings demonstrate how cells remodel purine metabolism upon ETC blockade and uncover a new metabolic vulnerability in tumors with low respiration.