Early hepatic proteomic signatures reveal metabolic changes in high-fat-induced obesity in rats.

The prevalence of diet-related obesity is increasing dramatically worldwide, making it important to understand the associated metabolic alterations in the liver. It is well known that obesity is a multifactorial condition that is the result of complex integration between many gene expressions and dietary factors. Obesity alone or in conjunction with other chronic diseases such as diabetes and insulin resistance causes many health problems and is considered a major risk factor for developing non-alcoholic steatohepatitis (NASH) and cirrhosis. In this study, we aimed to understand the molecular mechanisms underlying early hepatic changes in the pathophysiology of high-fat diet (HFD)-induced abdominal obesity in rats. Hepatic protein profiles of normal diet and HFD-induced obesity for 24 weeks were analysed using two-dimensional differential gel electrophoresis (DIGE) and protein identification by MS. Fifty-two proteins were identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF), and computer-assisted DIGE image software analysis showed that eighteen major proteins were significantly differentially expressed between comparable groups, with 2·0­4·0-fold change/more (P < 0·01). These proteins are regulated in response to a HFD, and differentially expressed proteins are involved in key metabolic pathways such as lipid metabolism, energy metabolism, detoxification, urea cycle and hepatic Ca homoeostasis. In addition, Western blot and immunohistochemistry of liver-specific arginase-1 (Arg-1) showed significant increased expression in the liver of high-fat-fed rats (P < 0·01). Further, Arg-1 expression was correlated with NASH patients with obesity-related fibrosis (F0­F4). It is concluded that high-fat content may affect changes in liver pathways and may be a therapeutic target for obesity-related liver disease. Arg-1 expressions may be a potential pathological marker for assessing the progression of the disease.

Metabolic alterations unravel the maternofetal immune responses with disease severity in pregnant women infected with SARS-CoV-2.

Pregnancy being an immune compromised state, coronavirus disease of 2019 (COVID-19) disease poses high risk of premature delivery and threat to fetus. Plasma metabolome regulates immune cellular responses, therefore we aimed to analyze the change in plasma secretome, metabolome, and immune cells with disease severity in COVID-19 positive pregnant females and their cord blood. COVID-19 reverse transcriptase-polymerase chain reaction positive pregnant females (n = 112) with asymptomatic (Asy) (n = 82), mild (n = 21), or moderate (n = 9) disease, healthy pregnant (n = 18), COVID-19 positive nonpregnant females (n = 7) were included. Eighty-two cord blood from COVID-19 positive and seven healthy cord blood were also analyzed. Mother's peripheral blood and cord blood were analyzed for untargeted metabolome profiling and cytokines by using high-resolution mass spectrometry and cytokine bead array. Immune scan was performed only in mothers' blood by flow cytometry. In Asy severe acute respiratory syndrome coronavirus 2 infection, the amino acid metabolic pathways such as glycine, serine, l-lactate, and threonine metabolism were upregulated with downregulation of riboflavin and tyrosine metabolism. However, with mild-to-moderate disease, the pyruvate and nicotinamide adenine dinucleotide (NAD+ ) metabolism were mostly altered. Cord blood mimicked the mother's metabolomic profiles by showing altered valine, leucine, isoleucine, glycine, serine, threonine in Asy and NAD+ , riboflavin metabolism in mild and moderate. Additionally, with disease severity tumor necrosis factor-α, interferon (IFN)-α, IFN-γ, interleukin (IL)-6 cytokine storm, IL-9 was raised in both mothers and neonates. Pyruvate, NAD metabolism and increase in IL-9 and IFN-γ had an impact on nonclassical monocytes, exhausted T and B cells. Our results demonstrated that immune-metabolic interplay in mother and fetus is influenced with increase in IL-9 and IFN-γ regulated pyruvate, lactate tricarboxylic acid, and riboflavin metabolism with context to disease severity.

Differential blood transcriptome modules predict response to corticosteroid therapy in alcoholic hepatitis.

BACKGROUND & AIMS: In patients with severe alcoholic hepatitis (SAH), little is known about the profile of peripheral blood mononuclear cells (PBMCs) at baseline and during corticosteroid therapy, among those who can be treated successfully with steroids (steroid-responders [R] and those who cannot (steroid-non-responders [NR]); 2 groups with different outcomes. METHODS: We performed RNA-seq analysis in PBMCs from 32 patients with definite SAH, at baseline and after 7 days of corticosteroids. The data were sorted into R and NR (n = 16, each group) using the Lille model and 346 blood transcription modules (BTMs) were identified. BTMs are predefined modules of highly co-expressed PBMC genes, which can determine specific immune cell types and cellular functions. The activity of each BTM was taken as the mean value of its member genes. RESULTS: At baseline, 345 BTMs had higher activity (i.e. were upregulated) in NR relative to R. The 100 most upregulated BTMs in NR, included several modules related to lymphoid lineage (T, B, and natural killer [NK] cells), modules for cell division and mitochondrial respiratory electron transport chain (ETC, relating to energy production), but only a few modules of myeloid cells. Correlation studies of BTM activities found features of significantly greater activation/proliferation and differentiation for T and B cells in NR relative to R. After 7 days of corticosteroids, NR had no significant changes in BTM activities relative to baseline, whereas R had downregulation of BTMs related to innate and adaptive immunity. CONCLUSIONS: At baseline and during corticosteroid therapy, increased activity in the PBMCs of gene modules related to activation/proliferation and differentiation of T and B cells, NK cells, and mitochondrial ETC, is a hallmark of SAH patients who are steroid-non-responders. LAY SUMMARY: Patients with severe alcoholic hepatitis receive steroid therapy as the main line of treatment; however, this treatment is ineffective in some patients. This only becomes apparent after 7 days of steroid therapy. We have developed an approach where it can be estimated if a patient is going to respond or not to steroid therapy using the gene expression information of blood cells. This method will allow clinicians to assess the response of patients to steroids earlier, and will help them in adopting alternate strategies if the treatment is found to be ineffective in a particular patient.

Modification Patterns of Urinary Albumin Correlates With Serum Albumin and Outcome in Severe Alcoholic Hepatitis.

BACKGROUND AND AIMS: Albumin modifications and deranged functions are well documented in serum of severe alcoholic hepatitis (SAH). We investigated whether urinary albumin (u-Alb) can serve as surrogate marker of circulatory albumin phenotype, functionality, and could predict outcome in SAH patients. PATIENTS AND METHODS: Baseline serum and urine samples from 100 SAH, 20 alcoholic cirrhosis, and 20 healthy controls were subjected to u-Alb, ischemia modified albumin (IMA), IMA to albumin ratio (IMAr), advanced oxidation protein products, advanced glycation end-products, albumin-binding capacity determination. In addition, SAH urinary samples were also analyzed at day 4 and day 7 to predict nonresponse to corticosteroid therapy. RESULTS: Urine and serum levels of IMA, advanced oxidation protein products and advanced glycation end-products were higher (P<0.05) in SAH versus alcoholic cirrhosis and healthy controls. IMAr was low in urine but high in serum of SAH (P<0.05). Albumin-binding capacity was lower (P<0.05) in both urinary and serum albumin of SAH. Urinary and serum albumin parameters showed direct correlation, whereas IMAr showed inverse correlation (cc>0.2, P<0.05). Baseline u-Alb level was significantly higher in SAH, and was correlated directly with corticosteroid treatment outcome and 12-month mortality in SAH. Baseline u-Alb showed an area under the receivers operating curve analysis of 0.7 and a hazard ratio of 1.23 for prediction of 12-month mortality in SAH. Baseline u-Alb level >9.0 mg/dL was associated with reduced 12-month survival in SAH (log rank <0.01). CONCLUSIONS: u-Alb modifications are reflective of serum albumin modifications. Further baseline u-Alb levels could be exploited to predict steroid response and mortality in SAH patients.

Pre-therapy liver transcriptome landscape in Indian and French patients with severe alcoholic hepatitis and steroid responsiveness.

Patients with severe alcoholic hepatitis (SAH) not responding to glucocorticoid therapy have higher mortality, though they do not differ in their baseline clinical characteristics and prognostic scores from those who respond to therapy. We hypothesized that the baseline hepatic gene expression differs between responders (R) and non-responders (NR). Baseline liver transcriptome was compared between R and NR in Indian (16 each) and French (5 NR, 3 R) patients with SAH. There were differentially expressed genes (DEGs) between NR and R, in Indian (1106 over-expressed, 96 under-expressed genes) and French patients (65 over-expressed, 142 under-expressed genes). Indian NR had features of hepatocyte senescence and French NR exhibited under-expression of genes involved in cell division, indicating a central defect in the capacity of hepatocytes for self-renewal in both populations. Markers of hepatic progenitor cell proliferation were either very few (Indian patients) or absent (French patients). No DEGs were enriched in inflammatory pathways and there were no differences in nuclear receptor subfamily 3 group C member 1 (NR3C1) transcript expression and splicing between NR and R. Our results reveal that baseline hepatic transcriptome is reflective of subsequent glucocorticoid non-response and indicate impaired regenerative potential of the liver as an underlying phenomenon in NR.