Diagnostic significance of nitrates and nitrites and L-arginine, in development of hepatorenal syndrome in patients with end stage alcoholic liver cirrhosis

Elucidating the effect of camel α-lactalbumin in modulating obesity-related metabolic disorders in an obese rat model

Camel α-Lactalbumin (α-LACc) has been shown to exert bioactivities for Reactive oxygen species (ROS) scavenging and anti-inflammation, showing the ability to treat obesity-related metabolic disorders. Herein, we present a novel process to purify α-LACc in a single chromatographic step from camel whey in a flow-through format. We also demonstrate the role of α-LACc modulation strategies for the treatment of obesity. An in-vivo study was systematically carried-out, in which an intragastric administration of α-LACc in rats experiencing obesity showed ameliorating effect on hepatic steatosis and dyslipidemia. In addition, we demonstrated that the reduction of inflammation and oxidative stress by α-LACc was effective, and importantly, the enhancement of antioxidant defenses was achieved. Furthermore, we found that the peroxynitrite scavenging ability of α-LACc could help restore the hepatorenal function. Finally, we showed that α-LACc could improve insulin resistance-associated glucose metabolism and insulin sensitivity disorders caused by obesity. This work has developed a novel one-step purification process of α-LACc from camel whey without the use of organic solvents. Our purified α-LACc may serve as a promising therapeutic agent in the treatment of obesity-related metabolic disorders by synergistically alleviating lipid accumulation, inflammation, oxidative stress and insulin sensitivity.

Oxidative stress, NOx/l-arginine ratio and glutathione/glutathione S-transferase ratio as predictors of 'sterile inflammation' in patients with alcoholic cirrhosis and hepatorenal syndrome type II

Continuous intake of alcohol leads to liver cirrhosis because of imbalance of oxidative stress/antioxidative defense and chronic ‘sterile inflammation’. Hepatorenal syndrome (HRS) is the most severe complication of liver cirrhosis. The aim of our study was to assess: (1) the oxidative stress/antioxidative defense markers such as malondialdehyde (MDA), oxidative glutathione (GSH) and glutathione S-transferase (GST), (2) inflammation [C-reactive protein (CRP)], and (3) nitrate/nitrite levels (NOx) and its substrate L-arginine level. The study enrolled three groups: a group with cirrhosis and HRS (48 patients), a group with cirrhosis without HRS (32 patients), and a control group (40 healthy blood donors). All the patients with cirrhosis and HRS had type II HRS. MDA concentration was significantly higher in the groups with cirrhosis with and without HRS. Significant positive correlation was documented between the MDA level and de Ritis coefficient (AST/ALT), a marker of liver damage severity; between MDA and inflammation (CRP); between MDA and NOx concentration in the groups with cirrhosis with and without HRS. The correlation between MDA and creatinine level was significant in the group with HRS. The levels of GSH and GST were significantly lower in the groups with cirrhosis with and without HRS. The results of the study revealed that an increase in MDA and NOx concentration, along with decreased values of antioxidative defense and L-arginine, may indicate that liver damage can have an influence on progression to renal failure.

Effect of nitric oxide pathway regulation on water/sodium balance and renal function in a rodent model of acute liver and renal failure

BACKGROUND

The pathomechanism of acute hepatorenal syndrome (HRS), a particular form of acute renal failure that occurs in the course of acute liver injury, is still poorly understood. The aim of our study was to estimate the influence of the activation and inhibition of the nitric oxide pathway on the water/sodium balance and development of acute renal failure in the course of HRS.

MATERIAL AND METHODS

We used male Sprague-Dawley rats in the acute galactosamine (Ga1N) model of HRS. The nitric oxide synthase (NOS) inhibitors L-NAME and L-arginine were administered intraperitoneally before and after liver damage.

RESULTS

HRS developed in all tested groups. L-NAME increased osmotic clearance and urine volume more effectively before liver injury. Furthermore, administration of L-NAME increased creatinine clearance both before and after Ga1N injection. A double dose of L-NAME did not yield further improvement before Ga1N injection, but improved creatinine clearance after Ga1N intoxication. Injection of L-arginine increased sodium excretion and urine volume, but only after liver injury. Moreover, L-arginine injected after Ga1N caused significant improvement of the creatinine clearance in a dose-dependent manner.

CONCLUSIONS

Our study shows that inhibition of the nitric oxide pathway improves parameters of water and sodium balance and prevents development of acute renal failure in the course of acute liver injury and liver failure. Activation of the nitric oxide system also has a favorable influence on water/sodium balance and renal failure, but only after liver injury.

Could serum nitrate and nitrite levels possibly predict hepatorenal syndrome in hepatitis C virus-related liver cirrhosis?

PURPOSE

This study aimed to determine whether serum levels of nitric oxide metabolites (nitrates and nitrites) correlate with renal dysfunction in patients with liver cirrhosis and, moreover, to assess nitric oxide metabolite (NOx) power for predicting hepatorenal syndrome (HRS) in such patients.

METHODS

Among patients admitted to the Tropical Medicine Department, Ain Shams University Hospital, a total of 60 patients with chronic hepatitis C-related liver cirrhosis were included in this study. Patients were divided into three groups. Group I included 20 patients with compensated liver cirrhosis (CLC). Group II included 20 patients with decompensated liver cirrhosis (DLC). Group III included 20 patients with decompensated liver cirrhosis and HRS. Twenty healthy subjects with no clinical or laboratory evidence of liver disease were enrolled as a control group (group IV).

RESULTS

Patients with HRS had a higher mean nitrite levels followed by DLC, then CLC, and then controls. The sensitivity and specificity of NO metabolites (nitrites) were 100 % and 93.3 %, respectively, with accuracy of 95 % at cutoff value of 387 μmol/L for diagnosing patients with HRS. There was a highly significant statistical difference between patients positive and negative for nitrites as regards renal profile (p = 0.000).

CONCLUSION

A strong relation between nitrite cutoff value and renal dysfunction in liver cirrhosis has been found. Also, patients with HRS had higher mean serum nitrite levels than decompensated liver cirrhosis or compensated liver cirrhosis, raising the possibility of using nitrate and nitrite levels as a predictor for HRS in HCV-related liver cirrhosis.