Peptidomics comparison of plant-based meat alternatives and processed meat after in vitro digestion.

Plant-based meat alternatives (PMAs) is a new type of food that meets people's health needs, but the lack of awareness of its nutritional properties limits product development and promotion. Here, we compared the similarities and differences of the nutritional properties of PMAs and meat before and after in vitro simulation of gastrointestinal digestion by chemical composition analysis, peptidomics and bioactivity tests. The molecular weights of Plant-based meat alternatives derived peptides (PDPs) as well as meat-derived peptides (MDPs) in the beef and pork groups were mainly concentrated in the low mass range from 800 Da to 1500 Da. The principal component analysis indicated that the composition of MDPs in the beef and pork groups significantly differed from PDPs but overlapped slightly with the chicken group. Also, there were very few common peptides among them. The proportion of high-biological-scoring peptides (33.3%-40%) in PDPs was more than that in MDPs (4.8%-20.8%). PDPs were predicted to have higher antibacterial activity than others. PDPs and MDPs showed a certain antioxidant capacity and angiotensin converting enzyme inhibitory activity (62.2%-92.5%) in vitro. Some peptides weakly inhibited the growth of Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) while promoting the growth of probiotics. This research provides a theoretical basis for in-depth exploration of the nutritional characteristics of PMAs.

Pulmonary toxicities from a 90-day chronic inhalation study with carbon black nanoparticles in rats related to the systemical immune effects.

Background: Recent years, there occurs heavy haze pollution in northern China during wintertime. The potential influence of airborne particulate matter (PM) on human health attracts great concern. The fuel-derived PM in the inhalable size range is dominated by aggregates of nanoparticles of Carbon black (CB). However, there are still lack of evidences especially regarding long-term exposure to explain the chronic effects of nanoscaled CB and the relative mechanism. Purpose: The objective of this study was to identify the potential mechanism of chronic effects of nanoscale CB. The systemic toxicity, immune suppression or activity and local toxicity were evaluated. Methods: 32 rats were divided into 2 groups: 30 mg/m3 CB exposure (nose only, 90 d, 6h/d) and control (clean air). Half of rats were scarified after exposure and another half of rats recovered for 14 days. Eight rats in each group were executed the lung function tests using a ventilated bias flow whole body plethysmograph (WBP). SDS-PAGE protocol was used to detect the deposition and retention of CB in lung of rats. HE staining was used to observe the changes of histopathology. Cell apoptosis was examined by TUNEL assay or flow cytometry. The levels of IL-6, IL-8, IL-17 and TNF-α in serum and lung tissue were evaluated with commercially available ELISA kit. The peripheral blood cell counts were detected by Auto 5-diff hematology analyzer. Results: The lung burden of CB was 16 mg in lung of rats after a 90-day exposure by MPPD. Fourteen percentages of the amount of CB accumulated at the end of the exposure period was cleared from the lung during the 14 dys recovery period. The lung function was significantly decreased and could not recover after a short time recovery. The fibroblasts and granuloma formation were found in lung. The levels of apoptosis and DNA damages were significantly increased in lung cells after CB inhalation. The cytokines levels in lung but not in serum were significantly increased in CB exposure group. The cell counts of WBC, monocytes and neutrophils had 1.72, 3.13, and 2.73-fold increases after CB exposure, respectively. The percentages of CD4+ lymphocytes and the rates of CD4+/CD8+ were statistically increased after CB exposure. The stimulation indexes of the peripheral blood lymphocytes were significantly decreased after CB exposure. In the CB exposure group, the disrupted histomorphology of thymus and spleen were found as well as the early apoptotic thymocytes had a 2.36-fold increase. Conclusion: CB induced the localized or direct toxicity and systemic immune toxicity. The direct and systemic immune responses had a combined effect on the lung damages caused by CB.

Reduction of oxidative damages induced by titanium dioxide nanoparticles correlates with induction of the Nrf2 pathway by GSPE supplementation in mice.

Titanium dioxide nanoparticles (TiO2 NPs) are widely used to additives in cosmetics, pharmaceuticals, paints and foods. Recent studies have demonstrated that TiO2 NPs increased the risk of cancer and the mechanism might relate with oxidative stress. Grape seed procyanidin extract (GSPE) is a natural compound which has been demonstrated to possess a wide array of pharmacological and biochemical actions, including anti-inflammatory, anti-carcinogenic, and antioxidant properties. Our data show that GSPE prevents the changes of histopathology and biomarkers in heart, liver and kidney that occur in mice exposed to TiO2 NPs. After pretreatment with GSPE, the DNA damage, reactive oxygen species (ROS) generation and malondialdehyde (MDA) content in mice exposed to TiO2 NPs had statistically significant decreases in dose dependent manners. GSPE increased the expression of nuclear factor erythroid 2 (NF-E2)-related factor 2 (Nrf2), NAD(P)H dehydrogenase[quinine] 1(NQO1), heme oxygenase 1 (HO-1) and glutamate-cysteine ligase catalytic subunit (GCLC). We conclude that grape seed procyanidin extract prevents the majority of tissue and molecular damage resulting from nanoparticle treatment. The protective effect of GSPE may be due to its strong antioxidative activities which related with the activated Nrf2 and its down-regulated genes including NQO1, HO-1 and GCLC.