In this study, the effects of γ-aminobutyric acid (GABA) on physio-biochemical metabolism, phenolic acid accumulation, and antioxidant system enhancement in germinated wheat under drought stress was investigated. The results showed that exogenous GABA reduced the oxidative damage in wheat seedlings caused by drought stress and enhanced the content of phenolics, with 1.0 mM being the most effective concentration. Six phenolic acids were detected in bound form, including p-hydroxybenzoic acid, vanillic acid, syringic acid, p-coumaric acid, ferulic acid, and sinapic acid. However, only syringic acid and p-coumaric acid were found in free form. A total of 1.0 mM of GABA enhanced the content of total phenolic acids by 28% and 22%, respectively, compared with that of drought stress, on day four and day six of germination. The activities of phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H) and 4-coumarate coenzyme A ligase (4CL) were activated by drought stress plus GABA treatment. Antioxidant enzyme activities were also induced. These results indicate that GABA treatment may be an effective way to relieve drought stress as it activates the antioxidant system of plants by inducing the accumulation of phenolics and the increase in antioxidant enzyme activity.

Lead (Pb) is a heavy metal environmental pollutant that can cause functional damage and anemia of immune organs. More and more evidence indicate that the toxicity of lead was related to apoptosis driven by oxidative stress and endoplasmic reticulum stress. This article mainly discusses the protective effect and mechanism of folic acid intervention on lead-induced spleen injury and apoptosis. In this study, Sprague-Dawley rats were randomly divided into control group, lead exposure group (0.2% lead acetate), folic acid + lead group (0.4 mg/kg folic acid and 0.2% lead acetate), and folic acid group (0.4 mg/kg folic acid). By recording and calculating the rat's initial body weight, final body weight, net weight gain, daily weight gain, and spleen index, observe the rat's weight change and spleen weight. And adopt the immunofluorescence staining method to determine the expression level of NrF2, HO-1, GRP78, CHOP protein in the spleen. The results showed that The 0.4 mg/kg folic acid diet did not significantly improve in the body weight and spleen index of lead-exposed rats (P > 0.05). While compared with the control group, the expression levels of HO-1 and CHOP protein were significantly increased in the lead exposure group (P < 0.05), and the expression levels of HO-1 and CHOP protein were significantly reduced in the folic acid intervention group (P < 0.05). In conclusion, lead exposure increased the expression levels of HO-1 and CHOP in the spleen of rats, and caused damage to the spleen. Folic acid down-regulated the expression levels of HO-1 and CHOP proteins through the two pathways of NrF2/HO-1 and GRP78/CHOP, thereby exerting a certain protective effect and alleviating the spleen caused by lead-induced oxidative stress and endoplasmic reticulum stress damage.

Many researchers have found that Pb exposure can cause oxidative stress damage to the body’s tissue. Black soybean peptide (BSP) has a variety of physiological functions, especially in terms of oxidative stress. Nevertheless, the mitigation function of BSPs on Pb-induced oxidative stress damage in PC12 cells has not been clearly defined. In this study, cell viability was detected by CCK8. Oxidative stress indicators, such as ROS, GSH/GSSG, MDA, SOD, CAT, GPx, and GR, were tested with biochemical kit. Protein expression of Keap1, Nrf2, and TXNIP was measured by Western blot. Compared with the control group, Pb reduced the cell viability of PC12 cells. However, BSP treatment significantly increased the viability of PC12 cells induced by lead exposure (p < 0.05). Lead can enrich the contents of MDA and ROS, but decrease the amount of CAT, SOD, GR, GPx, and GSH/GSSG in PC12 cells, while BSP can alleviate it (p < 0.05). Lead can enhance the expression of Keap1 and TXNIP proteins, but reduce Nrf2 expression. In contrast, BSPs reversed this phenomenon (p < 0.05). BSPs can alleviate oxidative stress injury induced by lead in PC12 cells through the Keap1/Nrf2/TXNIP signaling pathway.

The affinity of peptides is a crucial factor in studying peptide–protein interactions. Despite the development of various techniques to evaluate peptide–receptor affinity, the results may not always reflect the actual affinity of the peptides accurately. The current study provides a free tool to assess the actual peptide affinity based on virtual docking data. This study employed a dataset that combined actual peptide affinity information (active and inactive) and virtual peptide–receptor docking data, and different machine learning algorithms were utilized. Compared with the other algorithms, the random forest (RF) algorithm showed the best performance and was used in building three RF models using different numbers of significant features (four, three, and two). Further analysis revealed that the four-feature RF model achieved the highest Accuracy of 0.714 in classifying an independent unknown peptide dataset designed with the PEDV spike protein, and it also revealed overfitting problems in the other models. This four-feature RF model was used to evaluate peptide affinity by constructing the relationship between the actual affinity and the virtual docking scores of peptides to their receptors.