Chicken Protein Hydrolysates Have Anti-Inflammatory Effects on High-Fat Diet Induced Obesity in Mice

Plasma Cholesterol- and Body Fat-Lowering Effects of Chicken Protein Hydrolysate and Oil in High-Fat Fed Male Wistar Rats

Rest raw materials provide a new source of bioactive dietary ingredients, and this study aimed to determine the health effects of diets with chicken protein hydrolysate (CPH) and chicken oil (CO) generated from deboned chicken meat. Male Wistar rats (n = 56) were divided into seven groups in three predefined sub-experiments to study the effects of protein source (casein, chicken fillet, pork fillet, and CPH), the dose-effect of CPH (50% and 100% CPH), and the effects of combining CPH and CO. Rats were fed high-fat diets for 12 weeks, and casein and chicken fillet were used as controls in all sub-experiments. While casein, chicken-, or pork fillet diets resulted in similar weight gain and plasma lipid levels, the CPH diet reduced plasma total cholesterol. This effect was dose dependent and accompanied with the reduced hepatic activities of acetyl-CoA carboxylase and fatty acid synthase. Further, rats fed combined CPH and CO showed lower weight gain, and higher hepatic mitochondrial fatty acid oxidation, plasma L-carnitine, short-chain acylcarnitines, TMAO, and acetylcarnitine/palmitoylcarnitine. Thus, in male Wistar rats, CPH and CO lowered plasma cholesterol and increased hepatic fatty acid oxidation compared to whole protein diets, pointing to potential health-beneficial bioactive properties of these processed chicken rest raw materials.

Peptides and protein hydrolysates exhibiting anti-inflammatory activity: sources, structural features and modulation mechanisms

Inflammation is the response of the immune system to harmful stimuli such as tissue injury, infection or toxic chemicals, which has the aim of eliminating irritants or pathogenic microorganisms and enhancing tissue repair. Uncontrolled long-lasting acute inflammation can gradually progress to chronic, causing a variety of chronic inflammatory diseases that are usually treated with anti-inflammatory drugs, but most of them are inadequate to control chronic responses and are also associated with adverse side effects. Thus, many efforts are being directed to develop alternative and more selective anti-inflammatory therapies from natural products. One main field of interest is the obtaining of bioactive peptides exhibiting anti-inflammatory activity from sustainable protein sources like edible insects or agroindustry and fishing by-products. This work highlighted the structure-activity relationship of anti-inflammatory peptides. Small peptides with molecular weight under 1 kDa and amino acid chain length between 2 to 20 residues are generally the most active because of the higher probability to be absorbed in the intestine and penetrate into cells when compared with the larger size peptides. The presence of hydrophobic (Val, Ile, Pro) and positively charged (His, Arg, Lys) amino acids is another common occurrence for anti-inflammatory peptides. Interestingly, a high percentage (77%) of these bioactive peptides can be found in alternative sustainable protein sources such as Tenebrio molitor or sunflower, apart from its original protein source. However, not all of these peptides with anti-inflammatory potential in vitro achieve good scores by the in silico bioactivity predictors studied. Therefore, it is essential to implement current bioinformatics tools, in order to complement in vitro experiments with prior prediction of potential bioactive peptides.

Ameliorating Effects of Bioactive Peptides Extracted from Litopenaeus vannamei Wastes on Oxidative Stress, Glucose Regulation, and Autophagy Gene Expression in Nonalcoholic Fatty Liver-Induced Rats

This study aimed to investigate the effect of bioactive peptides from Litopenaeus vannamei on oxidative stress, glucose regulation, and autophagy gene expression in the induced nonalcoholic fatty liver rats. Bioactive peptides used in the current study were extracted in a progressive rise in temperature (40–60°C) (GP). For this purpose, twenty-four healthy male rats (initial weight, 230.1 ± 22 g) were divided in four experimental groups including control (standard diet), HFD (high-fat diet), HFD + GP20, and 300 (high-fat diet + 20, 300 mg peptides/kg body weight). After 70 days, the results indicated that experimental treatments did not affect the body and liver weight (P > 0.05), although the higher liver weight was seen in HFD treatment. Based on these results, the use of GP peptides improved antioxidant enzymes and decreased MDA concentration, and a significant difference was observed between peptide treatments and HFD (P < 0.05). In comparison to the HFD group, significantly lower liver enzymes (ALT and AST) were seen in peptide treatments (P < 0.05). Also, the results indicated that the lowest amylase, alkaline phosphatase, glucose, insulin, HOMA-IR, and inflammation cytokines (TNF-ɑ and IL-6) were seen in peptide groups. The autophagy gene expression was measured in the liver cells, and the results showed that, unlike HFD treatment, the use of GP peptides decreased Beclin 1, Atg7, and P62 expression in male rat's livers. Overall, the results of the current study demonstrated that the use of GP peptides at low concentration shows significant hypoglycemia and antioxidant properties in nonalcoholic fatty liver-induced rats.

Protective effect of protein hydrolysates from Litopenaeus vannamei waste on oxidative status, glucose regulation, and autophagy genes in non-alcoholic fatty liver disease in Wistar rats

Objective(s):

The effects of protein hydrolysates (FP) from Litopenaeus vannamei on oxidative stress, and autophagy gene expression was investigated in the NAFLD-induced rats.

Materials and Methods:

For this purpose, twenty-four male rats were divided into four groups: Control, High-fat diet (HFD), FP20+HFD, and FP300+HFD (20 and 300 mg FP /kg rat body weight) and fed for 70 days.

Results:

The results indicated that the rat body and relative weight of the liver were not affected by experimental treatments (P>0.05) although the highest relative weight of the liver was observed in HFD treatment. The highest and lowest values for antioxidant enzymes and MDA concentration were observed in FP treatments (P<0.05). Also, the results showed that FP significantly decreased liver enzymes (ALT, AST) in the liver in comparison with HFD treatment (P<0.05). Plasma biochemical indices were investigated and the lowest amylase, ALP, fasting glucose, insulin, HOMA-IR, triglycerides, cholesterol, and inflammation cytokines (TNF-α, IL-6) were seen in the FP treatments which had a significant difference with HFD (P<0.05). Autophagy gene expression in the liver cells was affected by experimental diets and the lowest expression of Beclin-1 and Atg7 was observed in HFD and FP300 treatments. Interestingly, the highest expression of LC3-ɪ and P62 was seen in HFD and FP treatments, not in the control.

Conclusion:

Overall, the results of this experiment indicated that FPs extracted from Whiteleg shrimp at 50 °C improve the oxidative status, glucose metabolism, and autophagy gene expression and could be used as a useful nutritional strategy in fatty liver prevention.

Trends and applications of food protein-origin hydrolysates and bioactive peptides

It was reported that protein hydrolysates or derived peptides have more functionalities than their parent protein. Most functional protein hydrolysates or peptides are identified from various food products, including plant, fish, and land-animal protein sources. Within a few decades, the application of food protein-origin functional hydrolysates or peptides could be divided into two main categories according to their applied intentions: 1) preservatives and bioactive packing materials; 2) nutraceutical ingredients. According to the literature, the applications of food protein-origin functional hydrolysates or peptides on food preservative and nutraceutical ingredients have attracted much attention. However, the approach method should be changed. Multi-activities, compound formulation, comprehensive evaluation, and the added value of by-products are possible strategies. Although there have been great results and findings in the functionalities of food protein-origin bioactive hydrolysates or peptides, there is still a big gap between the lab-scale results and practical applications. Via this narrative review on the current research, scientists, the food/health industry, and government authorities should cooperate to dig into the new material sources and the possible practical application.

A chicken protein hydrolysate exerts anti-atherosclerotic effect beyond plasma cholesterol-lowering activity in Apoe-/- mice

Chicken protein hydrolysates (CPHs) generated from rest raw materials through enzymatic hydrolysis using Corolase PP or Alcalase were shown to reduce inflammation and stimulate hepatic mitochondrial fatty acid oxidation in high-fat-fed mice. This study investigates the effect of CPH diets in atherosclerosis-prone apolipoprotein E-deficient (Apoe-/-) mice. Apoe-/- mice were divided into three groups of 12 animals and fed high-fat diets with casein (control), Alcalase CPH, or Corolase PP CPH. After 12 weeks, mice were sacrificed, blood samples were collected, and aorta was dissected for subsequent én face analysis. Mice fed Corolase PP CPH but not Alcalase CPH had significantly lower % atherosclerotic plaque area in the aortic arch compared to controls (p = .015 and p = .077, respectively). Plasma and liver cholesterol and triacylglycerol remained constant, but levels of the fatty acid C20:5n-3 were increased, accompanied by an elevated delta-5 desaturase index in both CPHs groups. Moreover, a significant reduction of plasma MCP-1 was detected in Corolase PP CPH compared to control. Overall, our data show that protein hydrolysates from chicken reduced atherosclerosis and attenuated systemic risk factors related to atherosclerotic disorders, not related to changes in the level of plasma cholesterol.