Progression to Cirrhosis Leads to Improvement in Atherogenic Milieu.

INTRODUCTION: The prevalence of coronary artery disease (CAD) is high among patients with cirrhosis; however, the impact of it on cardiovascular disease (CVD) is not known. The aim of the current study was to evaluate CVD events in patients with cirrhosis and impact of cirrhosis on biomarkers of atherogenesis. METHODS: The study included 682 patients with decompensated cirrhosis referred for liver transplantation (LT) evaluation between 2010 and 2017. All patients were followed until they experienced a CVD event, non-cardiac death, liver transplantation or last follow-up. To evaluate mechanistic link, patients with NASH cirrhosis were propensity matched 1:2 to non-cirrhosis NASH patients and biomarkers of atherogenic risk were compared. RESULTS: The composite CVD outcome occurred in 23(3.4%) patients after a median follow-up period of 585 days (IQR 139, 747). A strong association between presence of any CAD and CVD event was noted (HR = 6.8, 95% CI 2.9, 15.9) that was independent of age, gender, BMI, and MELD score. In competing risk model, the combined rate of LT and non-cardiac was significantly higher when compared to the rate of CVD events. Marker of insulin resistance and inflammation-related markers were similar in patients with and without cirrhosis. Patients with cirrhosis were more likely to have reduced VLDL, sdLDL-C, LDL-C, and triglycerides. Interestingly, patients with cirrhosis had an increase in serum HDL-2, the anti-atherogenic lipoprotein, and adiponectin, a protective serum adipokine. CONCLUSION: The risk of CVD events in patients with cirrhosis is low and may potentially be due to improvement in markers of atherogenic risk.

The role of noninvasive biomarkers in diagnosis and risk stratification in nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronically elevated liver enzymes. Diagnosis and risk stratification of NAFLD remains clinically challenge as patients with NAFLD are either asymptomatic or have nonspecific presenting complaints and may have normal liver enzymes. Nonalcoholic steatohepatitis (NASH), the clinically aggressive variant of NAFLD, is also difficult to differentiate noninvasively, and a liver biopsy is required to definitively diagnose NASH. Thus, the definitive diagnosis and risk stratification of NAFLD is embedded in histological assessment of the liver. Several clinical aides been investigated in an attempt to risk stratify and identify patients noninvasively as doing a liver biopsy in all patients with NAFLD are not feasible. Since these biomarkers are unable to differentiate NASH from non-NASH, they have leveraged biochemical changes within the liver as patients progress to varying degree of hepatic fibrosis to identify patients with moderate fibrosis (fibrosis stage 2 or greater) and advanced fibrosis (fibrosis stage 3 or greater) to help guide the need for additional and more definitive workup. These clinical aides span from by-products of apoptosis to statistical modelling of clinically available data to identify 'at-risk' patients with NAFLD. The current review will focus the diagnostic performance of these noninvasive serum-based biomarkers in NAFLD.

Why Do Lifestyle Recommendations Fail in Most Patients with Nonalcoholic Fatty Liver Disease?

Nonalcoholic fatty liver disease has been recognized as a major health burden. The efficacy and safety profile of pharmacotherapy in the treatment of nonalcoholic fatty liver disease remains uncertain; therefore, lifestyle modification is the first line of treatment. Based on available data, patients should optimally achieve at least a 5% to 10% weight reduction for histologic improvement. There is no clear consensus on the optimal diet or exercise regimen. Sustainability of any intervention is key to success; however, compliance has been a major issue in clinical trials. This finding underscores the importance of multidisciplinary strategies to achieve targeted weigh loss.

Office-Based Weight Loss Counseling Is Ineffective in Liver Transplant Recipients.

BACKGROUND: Weight gain after liver transplantation (LT) is a predictor of major morbidity and mortality post-LT; however, there are no data regarding weight loss following LT. The current study evaluates the effectiveness of standard lifestyle intervention in LT recipients. METHODS: All adult LT recipients with body mass index (BMI) ≥ 25 kg/m2 who followed up in post-LT clinic from January 2013 to January 2016 were given standard lifestyle advice based on societal recommendations which was reinforced at 24 weeks. Patients were followed for a total of 48 weeks to assess the impact of such advice on weight. Primary outcome was achieving weight loss ≥ 5% of the body weight after 48 weeks of follow-up. RESULTS: A total of 151 patients with 86 (56.0%) overweight and 65 (44.0%) obese patients were enrolled in the study. The mean BMI at baseline increased from 30.2 ± 3.7 to 30.9 ± 4.3 kg/m2 at 48-week follow-up (p = 0.001). Over the course of study, 58 (38.4%) patients lost any weight and weight loss greater than 5% and 10% occurred in only 18 (11.9%) and 8 (5.3%) of the entire cohort, respectively. Higher level of education was associated with increased likelihood of weight loss (OR 9.8, 95% CI 2.6, 36.9, p = 0.001), while nonalcoholic steatohepatitis as etiology of liver disease (HR 3.7, 95% CI 1.4, 9.7, p = 0.007) was associated with weight gain. CONCLUSION: The practice of office-based lifestyle intervention is ineffective in achieving clinically significant weight loss in LT recipients, and additional strategies are required to mitigate post-LT weight gain.

The cytotoxicity of BAMLET complexes is due to oleic acid and independent of the α-lactalbumin component.

Lipid-protein complexes comprised of oleic acid (OA) non-covalently coupled to human/bovine α-lactalbumin, named HAMLET/BAMLET, display cytotoxic properties against cancer cells. However, there is still a substantial debate about the role of the protein in these complexes. To shed light into this, we obtained three different BAMLET complexes using varying synthesis conditions. Our data suggest that to form active BAMLET particles, OA has to reach critical micelle concentration with an approximate diameter of 250 nm. Proteolysis experiments on BAMLET show that OA protects the protein and is probably located on the surface, consistent with a micelle-like structure. Native or unfolded α-lactalbumin without OA lacked any tumoricidal activity. In contrast, OA alone killed cancer cells with the same efficiency at equimolar concentrations as its formulation as BAMLET. Our data show unequivocally that the cytotoxicity of the BAMLET complex is exclusively due to OA and that OA alone, when formulated as a micelle, is as toxic as the BAMLET complex. The contradictory literature results on the cytotoxicity of BAMLET might be explained by our finding that it was imperative to sonicate the samples to obtain toxic OA.

Chemical glycosylation of cytochrome c improves physical and chemical protein stability.

BACKGROUND: Cytochrome c (Cyt c) is an apoptosis-initiating protein when released into the cytoplasm of eukaryotic cells and therefore a possible cancer drug candidate. Although proteins have been increasingly important as pharmaceutical agents, their chemical and physical instability during production, storage, and delivery remains a problem. Chemical glycosylation has been devised as a method to increase protein stability and thus enhance their long-lasting bioavailability. RESULTS: Three different molecular weight glycans (lactose and two dextrans with 1 kD and 10 kD) were chemically coupled to surface exposed Cyt c lysine (Lys) residues using succinimidyl chemistry via amide bonds. Five neo-glycoconjugates were synthesized, Lac4-Cyt-c, Lac9-Cyt-c, Dex5(10kD)-Cyt-c, Dex8(10kD)-Cyt-c, and Dex3(1kD)-Cyt-c. Subsequently, we investigated glycoconjugate structure, activity, and stability. Circular dichroism (CD) spectra demonstrated that Cyt c glycosylation did not cause significant changes to the secondary structure, while high glycosylation levels caused some minor tertiary structure perturbations. Functionality of the Cyt c glycoconjugates was determined by performing cell-free caspase 3 and caspase 9 induction assays and by measuring the peroxidase-like pseudo enzyme activity. The glycoconjugates showed ≥94% residual enzyme activity and 86 ± 3 to 95 ± 1% relative caspase 3 activation compared to non-modified Cyt c. Caspase 9 activation by the glycoconjugates was with 92 ± 7% to 96 ± 4% within the error the same as the caspase 3 activation. There were no major changes in Cyt c activity upon glycosylation. Incubation of Dex3(1 kD)-Cyt c with mercaptoethanol caused significant loss in the tertiary structure and a drop in caspase 3 and 9 activation to only 24 ± 8% and 26 ± 6%, respectively. This demonstrates that tertiary structure intactness of Cyt c was essential for apoptosis induction. Furthermore, glycosylation protected Cyt c from detrimental effects by some stresses (i.e., elevated temperature and humidity) and from proteolytic degradation. In addition, non-modified Cyt c was more susceptible to denaturation by a water-organic solvent interface than its glycoconjugates, important for the formulation in polymers. CONCLUSION: The results demonstrate that chemical glycosylation is a potentially valuable method to increase Cyt c stability during formulation and storage and potentially during its application after administration.