Pasteurization induced protein interaction decreased the potential allergenicity of ovalbumin and ovomucoid in egg white.

BACKGROUND: Approximately 9.9% of young children in China suffer from egg allergies. Ovalbumin (OVA) and ovomucoid (OVM) are both the main allergens with higher allergenicity in egg white. The previous studies mainly focused on the effects of pasteurization on the structure and allergenicity of the isolated protein itself. The effects of the interaction between OVA and OVM on their spatial structure and allergenicity under pasteurization are still unclear. Therefore, in this study, the spectroscopic, immunological, and cytological methods were used to investigate the effects on OVA and OVM by their interactions which were induced by the following pasteurization, heating for 10 min at 60, 65, and 70 °C, respectively. RESULTS: Results indicated that OVA and OVM could form macromolecular aggregates by their interaction at 70 °C, and their solubility was decreased while turbidity was increased. The spatial structures of OVA and OVM were both changed by their interaction, when pasteurization temperature was at 70 °C the exposure of their hydrophobic groups and α-helix content were decreased while their ß-sheet was increased. The potential allergenicity of OVA and OVM was also changed, which showed that the immunoglobulin G (IgG)-binding ability of OVA and OVM could be increased, and their IgE-binding ability was decreased a bit. The releases of interleukin 4 (IL-4), IL-6, ß-HEX, histamine and tumor necrosis factor alpha (TNF-α) from OVA-OVM-induced KU812 cells were all decreased at 70 °C. CONCLUSION: Therefore, according to the results, if the liquid egg products were pasteurized for 10 min, the temperature of 70 °C should be carefully considered. © 2022 Society of Chemical Industry.

Systems pharmacology reveals the mechanism of activity of Ge-Gen-Qin-Lian decoction against LPS-induced acute lung injury: A novel strategy for exploring active components and effective mechanism of TCM formulae.

Acute lung injury (ALI), a severe and life-threatening inflammation of the lung, with high morbidity and mortality, underscoring the urgent need for novel treatments. Ge-Gen-Qin-Lian decoction (GQD), a classic Chinese herbal formula, has been widely used to treat intestine-related diseases in the clinic for centuries. In recent years, a growing number of studies have found that GQD has a favorable anti-inflammatory effect. With the further study on the viscera microbiota, the link between the lungs and the gut-the gut-lung axis has been established. Based on the theory of the gut-lung axis, we used systems pharmacology to explore the effects and mechanisms of GQD treatment in ALI. Hypothesizing that GQD inhibits ALI progression, we used the experimental model of lipopolysaccharide (LPS)-induced ALI in Balb/c mice to evaluate the therapeutic potential of GQD. Our results showed that GQD exerted protective effects against LPS-induced ALI by reducing pulmonary edema and microvascular permeability. Meanwhile, GQD can downregulate the expression of LPS-induced TNF-α, IL-1ß, and IL-6 in lung tissue, bronchoalveolar lavage fluid (BLAF), and serum. To further understand the molecular mechanism of GQD in the treatment of ALI, we used the network pharmacology to predict the disease targets of the active components of GQD. Lung tissue and serum samples of the mice were separately analyzed by transcriptomics and metabolomics. KEGG pathway analysis of network pharmacology and transcriptomics indicated that PI3K/Akt signaling pathway was significantly enriched, suggesting that it may be the main regulatory pathway for GQD treatment of ALI. By immunohistochemical analysis and apoptosis detection, it was verified that GQD can inhibit ALI apoptosis through PI3K/Akt signaling pathway. Then, we used the PI3K inhibitor LY294002 to block the PI3K/Akt signaling pathway, and reversely verified that the PI3K/Akt signaling pathway is the main pathway of GQD anti-ALI. In addition, differential metabolites in mice serum samples indicate that GQD can inhibit the inflammatory process of ALI by reversing the imbalance of energy metabolism. Our study showed that, GQD did have a better therapeutic effect on ALI, and initially elucidated its molecular mechanism. Thus, GQD could be exploited to develop novel therapeutics for ALI. Moreover, our study also provides a novel strategy to explore active components and effective mechanism of TCM formula combined with TCM theory to treat ALI.

Suppression of expression of the putative receptor-like kinase gene NRRB enhances resistance to bacterial leaf streak in rice.

Bacterial leaf streak (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) is an important disease of rice, which is responsible for the economic losses worldwide. Functional investigation of differentially expressed protein genes (DEPGs) from rice (Oryza sativa L.) upon Xoc infection provides insight into the molecular mechanism of rice-Xoc interactions. Here, we show that one of DEPGs designated NRRB plays a role in rice-Xoc interactions. NRRB, a receptor-like cytoplasmic kinase gene was preferentially expressed in leaf blades and leaf sheaths where the pathogen colonized. Its transcription was depressed by two defense-signal compounds salicylic acid and 1-aminocyclopropane-1-carboxylic-acid, but was activated by wounding and abscisic acid. Additionally, a plenty of cis-elements associated with stress responses were discovered in the promoter region of NRRB. These data suggest that NRRB is involved in stress responses. More importantly, the NRRB-suppressing rice plants exhibited enhanced resistance against BLS, with the markedly shorter average lesion length than that of the wild type. Furthermore, transcription of some salicylic acid synthesis-related and pathogenesis-related genes including PAD4, PR1a and WRKY13 in transgenic plants was activated, implying that enhanced resistance to BLS might be mediated by the activation of the SA signaling pathway. In conclusion, NRRB gene is involved in various stress responses and regulating resistance to BLS, therefore it might be one of useful genes for rice improvement in future.

Overexpression of a new stress-repressive gene OsDSR2 encoding a protein with a DUF966 domain increases salt and simulated drought stress sensitivities and reduces ABA sensitivity in rice.

Domain of Unknown Function 966 (DUF966) gene family was found in the protein family database, which consisted of seven genes in rice. The proteins encoded by these genes contained one or two highly conserved DUF966 domains. The available data of public microarray databases implied that these genes might play crucial roles in plant response to abiotic stresses. In this study, a member of the DUF966 gene family, DUF966-stress repressive gene 2 in Oryza sativa (OsDSR2, Loc_Os01g62200), was cloned and its role in rice responding to salt and simulated drought stresses was functionally characterized. OsDSR2 was expressed mainly in nodes of stems and leaf blades from rice. Expression profile analysis of adversity showed that OsDSR2 had different transcriptional responses to salt, drought, cold, heat and oxidative (H2O2) stresses, as well as abscisic acid (ABA), methyl jasmonate, salicylic acid, gibberellin acid and auxin treatments. Transient expression demonstrated that OsDSR2 was localized in the membrane and nucleus. Overexpression of OsDSR2 could increase salt and simulated drought (polyethyleneglycol)-stress sensitivities in rice by downregulating the expression of ABA- and stress-responsive genes including OsNCED4, SNAC1, OsbZIP23, P5CS, Oslea3 and rab16C. Furthermore, OsDSR2-overexpressing plants showed reduced ABA sensitivity during the post-germination stage. These results suggested that OsDSR2 negatively regulated rice response to salt and simulated drought stresses as well as ABA signaling, which provided some useful data for understanding the functional roles of DUF966 family genes in abiotic stress responses in plants.

Over-expression in the nucleotide-binding site-leucine rich repeat gene DEPG1 increases susceptibility to bacterial leaf streak disease in transgenic rice plants.

Bacterial leaf streak of rice (BLS) caused by Xanthomonas oryzae pv. oryzicola (Xoc) is a widely-spread disease in the main rice-producing areas of the world. Investigating the genes that play roles in rice-Xoc interactions helps us to understand the defense signaling pathway in rice. Here we report a differentially expressed protein gene (DEPG1), which regulates susceptibility to BLS. DEPG1 is a nucleotide-binding site (NBS)-leucine rich repeat (LRR) gene, and the deduced protein sequence of DEPG1 has approximately 64% identity with that of the disease resistance gene Pi37. Phylogenetic analysis of DEPG1 and the 18 characterized NBS-LRR genes revealed that DEPG1 is more closely related to Pi37. DEPG1 protein is located to the cytoplasm, which was confirmed by transient expression of DEPG1-GFP (green fluorescent protein) fusion construct in onion epidermal cells. Semi-quantitative PCR assays showed that DEPG1 is widely expressed in rice, and is preferentially expressed in internodes, leaf blades, leaf sheaths and flag leaves. Observation of cross sections of leaves from the transgenic plants with a DEPG1-promoter::glucuronidase (GUS) fusion gene revealed that DEPG1 is also highly expressed in mesophyll tissues where Xoc mainly colonizes. Additionally, Xoc negatively regulates expression of DEPG1 at the early stage of the pathogen infection, and so do the three defense-signal compounds including salicylic acid (SA), methyl jasmonate (MeJA) and 1-aminocyclopropane-1-carboxylic-acid (ACC). Transgenic rice plants overexpressing DEPG1 exhibit enhanced susceptibility to Xoc compared to the wild-type controls. Moreover, enhanced susceptibility to Xoc may be mediated by inhibition of the expression of some SA biosynthesis-related genes and pathogenesis-related genes that may contribute to the disease resistance. Taken together, DEPG1 plays roles in the interactions between rice and BLS pathogen Xoc.

Structural characterization and cardioprotective activity of a novel polysaccharide from Fructus aurantii.

Fructus aurantii is a well-known plant commonly used to treat cardiovascular diseases in China. The Fructus aurantii polysaccharide CALB-3 has been shown to exhibit antioxidant activity in vitro and in vivo. We aimed to further characterize the structure of CALB-3 and investigate its protective effects against hypoxia/reoxygenation-mediated myocardial injury in vitro. To this end, here, the effect of CALB-3 was tested against hypoxia/reoxygenation-induced oxidative stress, antioxidant enzyme and reactive oxygen species levels, and apoptosis-related protein expression in H9c2 cells. Our results showed that CALB-3 had a molecular weight greater than 805.0 kDa and a â†’ 3)-α-Galp-(1→, →3, 4)-α-Galp-(1→, and →3)-ß-Arap-(1 â†’ backbone. Pretreatment with CALB-3 elevated survival rate, improved endogenous antioxidant enzyme activity, inhibited reactive oxygen species production, reduced mitochondrial membrane potential, downregulated the pro-apoptosis protein Bax, and upregulated the anti-apoptosis protein Bcl-2. The protective effects were correlated with Akt signaling, suggesting that CALB-3 exerts its cardioprotective effects via Akt signaling.

Cardioprotective effects of a Fructus Aurantii polysaccharide in isoproterenol-induced myocardial ischemic rats.

CALB-3, a purified acidic hetero-polysaccharide isolated from Fructus aurantii, has been shown to exert cardioprotective effects in vitro. Recently, we investigated the protective effects of CALB-3 on myocardial injury and its possible mechanisms of action using a rat model of myocardial ischemia. In this study, a myocardial ischemia model was established via intragastric administration of 2 mg/kg isoproterenol (ISO) to male Sprague-Dawley rats (200-220 g) daily for 3 days. We found that pretreatment with CALB-3 (50, 100, and 200 mg/kg, i.g.) daily for 21 days prevented ISO-induced myocardial damage, including improvement in electrocardiographic parameters, and decrease in serum cardiac enzymes, heart vacuolation, and TUNEL-positive cells. We used western blotting to identify the underlying mechanisms and determine the possible signal pathways involved. We found that CALB-3 pretreatment prevented apoptosis, increased the expression of antioxidant enzymes, and enhanced the binding of Nrf2 to the antioxidant response element. In addition, CALB-3 activated the phosphorylation of PI3K/Akt and ERK to increase the cytoprotective effect. Overall, our results show that CALB-3 is a promising polysaccharide for protecting against myocardial injury induced by ISO.

Advances in research into the mechanisms of Chinese Materia Medica against acute lung injury.

Acute lung injury (ALI) is a common and serious disease. Numerous treatment options are available but they do not improve quality of life or reduce mortality for ALI patients. Here, we review the treatments for ALI to provide basic data for ALI drug therapy research and development. Chinese Materia Medica (CMM) has long been the traditional clinical approach in China for the treatment of ALI and it has proven efficacy. The continued study of CMM has disclosed new potential therapeutic ingredients for ALI. However, few reviews summarize the currently available CMM-based anti-ALI drugs. Therefore, the systematic analysis of research progress in anti-ALI CMM is of great academic and clinical value. The aim of the present review is to describe CMM-based research progress in ALI treatment. Data were compiled by electronic retrieval (CNKI, SciFinder, PubMeds, Google Scholar, Web of Science) and from articles, patents and ethnopharmacological literature in university libraries were systematically studied. This review introduces progress in research on the etiology and mechanisms of ALI, the anti-ALI theory and modes of action in traditional Chinese medicine (TCM), anti-ALI active constituents of CMM, research progress in experimental methods of CMM anti-ALI, the anti-ALI molecular mechanisms of CMM, the anti-ALI efficacy of CMM formulae, and the potential toxicity of CMM and the antidotes for it. Scholars have investigated the anti-ALI molecular mechanism of CMM from various direction and have made substantial progress. This research explored the above aspects, enriched the anti-ALI theory of CMM and established the clinical significance and developmental prospects of ALI treatment by CMM. Because of the high frequency of drugs such as glucocorticoids or antibiotics, Western medicine lacks the advantages of CMM in terms of overall anti-ALI efficacy. In the future, the development of CMM-based anti-ALI therapies will become a major trend in the field of ALI drug development. Successful clinical safety and efficacy validations will promote and encourage the use of CMM. It provides fundamental theoretical support for the discovery and use of CMM resources through the comprehensive analysis of various anti-ALI CMM report databases.

Cardioprotective effect exerted by Timosaponin Bâ ¡ through the regulation of endoplasmic stress-induced apoptosis.

BACKGROUND: Timosaponin BⅡ (TBⅡ), one of the primary bioactive compounds from Anemarrhena asphodeloides Bunge, possesses potential cardioprotective effects. However, the mechanism underlying TBⅡ-mediated cardioprotection, especially the involvement of endoplasmic reticulum stress, remains largely unknown. PURPOSE: This study was designed to evaluate the role of TBⅡ in myocardial injury protection and explore its possible mechanisms. METHODS: In vivo models of isoproterenol-induced myocardial injury and H2O2-induced cytotoxicty were established to investigate the effect of anti-myocardial injury of TBⅡ. The potential mechanisms were investigated in vitro and in vivo using multiple detection methods like electrocardiography, histo-pathological examination, JC-1 staining, TUNEL staining, ELISA technology, and western blot analysis. RESULTS: In vivo study revealed that TBⅡ improved electrocardiography and heart vacuolation, reduced myocyte apoptosis, and improved the antioxidant potential. In vitro investigation demonstrated that TBⅡ pretreatment inhibited ER stress-mediated apoptosis pathways. Further investigation of the underlying mechanisms revealed that TBⅡ prevented H2O2-induced H9c2 cardiomyocytes injury by the PI3K/Akt pathways, whereas the addition of LY294002, the pharmacologic antagonist of PI3K, attenuated TBⅡ-induced expression of apoptotic protein and cytoprotective effects. CONCLUSION: These results suggested that TBⅡ protects against myocardial injury in vitro and enhances cellular defense capacity by inhibiting ER stress-mediated apoptosis pathways in vivo by activating the PI3K/Akt pathways.