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Fracanzani, A. L.

Publications and source records attributed to Fracanzani, A. L..

2 recordsLinked to original sources

Artificial intelligence as a ploy to delve into the intricate relationship between genetics and mitochondria in MASLD patients

Background and AimsMitochondrial (mt-) dysfunction is a hallmark of progressive MASLD. MtDNA copy number (mtDNA-CN) and cell-free circulating mtDNA (ccf-mtDNA), which reflect mt-mass and mt-dysfunction, respectively, are gaining attention as non-invasive disease biomarkers. We previously demonstrated that PNPLA3/MBOAT7/TM6SF2 deficiency in HepG2 cells increased mt-mass, mtDNA-CN and ccf-mtDNA. This study furtherly explored mt-biogenesis, function and mt-biomarkers in biopsied MASLD patients from a Discovery (n=28) and a Validation (n=824) cohort, stratified by the number of risk variants (NRV=3). We took advantage of artificial intelligence (AI) to develop new risk scores, predicting MASLD evolution by integrating anthropometric and genetic data (Age, BMI, NRV) with mt-biomarkers. MethodsHepatic mt-morphology and dynamics were assessed by TEM, IHC and gene expression. mtDNA-CN and ccf-mtDNA were measured in PBMCs and serum samples. GPT-4 was employed as AI tool to support the construction of novel risk scores for MASLD progressive forms (MASH, fibrosis and HCC). ResultsIn the Discovery cohort, NRV=3 patients showed the highest mt-mass and significant mt-morphological changes (i.e. membranes rupture). An elevated PGC-1, OPA1, DRP1 and PINK1, markers of mt-biogenesis, fusion and fission were found in these patients, supporting an enhanced mt-dynamics. However, PRKN protein levels were reduced, suggesting a premature block of mitophagy. In the Validation cohort, PGC-1 mRNA levels and mtDNA-CN were significantly higher in NRV=3 compared to patients with 1,2 or no variants. Circulating mtDNA-CN and ccf-mtDNA were augmented in NRV=3 patients and correlated with genetics and MASLD severity at multivariate analysis, supporting that both may independently modulate mt-dynamics and activity. By exploiting rsGPT-4 we then optimized the combination of non-invasive variables to get prediction models named Mitochondrial, Anthropometric, and Genetic Integration with Computational intelligence ("MAGIC-") for assessing MASH, fibrosis, and HCC, respectively. The MAGIC-MASH and MAGIC-Fib models showed AUCs of 73% and 76% in detecting MASH and fibrosis >1. Of note, MAGIC-HCC achieved an AUC of 86% (95% CI: 0.823-0.885), with 78.6% sensitivity and 81.5% specificity thus resulting the best score for the desired outcome. ConclusionsmtDNA-CN and ccf-mtDNA may have pathological and prognostic significance in MASLD patients, especially in those genetically-predisposed.

genetics↗

Serum mitochondrial bioenergetics as fingerprint of the hepatic one: how to monitor genetic MASLD

Background & AimsMetabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) pathogenesis is shaped by genetics and mitochondrial dysfunction. Recently, we demonstrated that the co-presence of patatin- like phospholipase domain-containing 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2) and membrane bound o-acyltransferase domain-containing 7 (MBOAT7) polymorphisms predisposes to disease progression in MASLD patients and that their deletion contributes to mitochondrial (mt) maladaptation in an in- vitro model. In this work we deepened the impact of genes silencing on mitochondrial dynamism. Then we restored TM6SF2 and/or MBOAT7 wild-type (WT) proteins in the in-vitro model to evaluate the rescue of organelles morphology/function. Finally, we compared hepatic and peripheral mt-bioenrgetics in MASLD patients carrying PNPLA3, MBOAT7 and/or TM6SF2 loss-of-function variations. MethodsWT proteins were overexpressed through lentiviral transfection, mt-respiration was assessed by Seahorse. ResultsThe restore of MBOAT7 and/or TM6SF2 wild-type proteins resulted in the assembly of spaghetti- shaped mitochondria with improved OXPHOS capacity. Mitochondrial activity was assessed in liver biopsies and peripheral blood mononuclear cells of biopsy-proven (n=44;Discovery cohort) and noninvasively assessed (n=45;Fibroscan-MASLD cohort) MASLD patients stratified according to the presence of the 3 at-risk variants alongside in unrelated liver disease patients (n=45;Unrelated liver disease cohort). In the Discovery cohort, the hepatic bioenergetic profile fully reflecting the circulating one, was impaired in carriers of the risk variants, more so when in combination. We confirmed the lowered serum respirometry in the Fibroscan-MASLD cohort. Finally, the circulating respiration did not change in unrelated liver disease patients, thus demonstrating that it was specifically impaired in MASLD. ConclusionsThese results boosted the relevance of mitochondrial circulating respirometry to outline genetically-based MASLD.

genetics↗