pH-responsive in situ gelling properties of thiolated citrus high-methoxyl pectin and its potential gel mechanism.

pH-responsive in situ gelling properties of thiolated citrus high-methoxyl pectin (TCHMP) were investigated in this study. The gelation capacity results revealed that the in situ gelation behavior of TCHMP only occurred when the pH value was higher than 6.25. The gel strength increased from 26.63 g to 42.77 g as the pH value increased from 7.4 to 8.9. Rheological measurements confirmed that the apparent viscosity and viscoelasticity of TCHMP were highly dependent on pH value and dialysis time. Compared with the control group, the apparent viscosity of TCHMP dialyzed in phosphate-buffered saline (PBS) of pH 8.9 for 180 min increased 695-fold. During the dialysis process of TCHMP at different pH values (7.4-8.9), the final thiol groups content decreased and the final disulfide bonds content increased with the increase in pH value. This illustrates that the mechanism of in situ gelation is mainly the oxidation of thiol-thiol groups to form disulfide bonds. These results can put forward new insights into the pH-responsive in situ gelling properties of TCHMP and provide a theoretical basis for the application of TCHMP in neutral and alkaline gel systems.

Compound treatment of thiolated citrus high-methoxyl pectin and sodium phosphate dibasic anhydrous improved gluten network structure.

The effects of pectin or thiolated pectin alone and combined with sodium phosphate dibasic anhydrous (Na2HPO4) on the performances of gluten were studied. Results showed that compared with pectin treated gluten, the thiols of thiolated pectin treated gluten increased by 8.7 times. Analysis of the extensibility and rheological properties revealed that pectin reduced gluten strength, whereas thiolated pectin improved the strength and viscoelasticity of gluten, especially with the assistance of Na2HPO4. Furthermore, thiolated pectin and Na2HPO4 compound increased enthalpy (ΔH, from 150.42 to 168.60 J/g) and decreased Imax (from 5255.33 to 2775.33) markedly, indicating gluten aggregation. The highest ß-sheet (76.47%) and the lowest α-helix/ß-sheet ratio (0.11) were found in gluten treated with thiolated pectin and Na2HPO4 and suggested gluten stability was enhanced. SEM observation confirmed that thiolated pectin and Na2HPO4 compound strengthened the gluten structure. These results are of great significance for the supplementation of pectin in wheat products.

Evidence construction of baicalin for treating myocardial ischemia diseases: A preclinical meta-analysis.

BACKGROUND: Baicalin, a flavonoid glycoside isolated from Scutellaria baicalensis Georgi, has shown potential pharmacological effects on myocardial ischemia diseases. Nevertheless, systematic preclinical studies on baicalin in the treatment of ischemic diseases are scarce. PURPOSE: To assess the efficacy and potential mechanisms of baicalin in myocardial ischemia (RI), myocardial ischemia-reperfusion (IR) injury and myocardial infarction (MI) animal models for future clinical research. METHODS: Preclinical studies published prior to August 27th, 2022 were retrieved from PubMed, Embase, Web of Science and Cochrane Library. CAMARADES list was used to evaluate the quality of included researches. Meta-analyses of cardiac pathology and function parameters, myocardial injury markers and other indicators were performed by STATA 15.0 software. Potential mechanisms are categorized and summarized. Dose-response interval analyses were used to analyze the dose-response relationship between baicalin and myocardial ischemia disease. RESULTS: Fourteen studies and 222 animals were included in the analysis. The results showed that compared with the control group, baicalin could reduce myocardial infarction size associated with cardiac pathological condition and the corresponding cardiac pathological index containing CK-MB, CK and cTnT. Additionally, heart function indicators including LVSP, LVFS, LVEF, -dp/dt max, dp/dt max were increased by baicalin. As for subgroup analyses, baicalin also demonstrated certain effect on CK-MB and LVSP by administration method or stage. Furthermore, it displayed obvious effect on myocardial ischemia diseases when the dose is maintained at 100-150 mg/kg based on dosage analyses. CONCLUSION: Based on the relevant literature retrieved, this is the first meta-analysis on baicalin in treating myocardial ischemia diseases. Notably, we linked the dynamic development of the disease and discussed it pertinently, from RI, IR injury to MI. Baicalin exhibits positive effects on myocardial ischemia diseases (especially when the dose is 100-150 mg/kg), which is achieved by regulating key pathological indicators and various signaling pathways.

Codonopsis pilosula polysaccharide attenuates Aß toxicity and cognitive defects in APP/PS1 mice.

Codonopsis pilosula Polysaccharides (CPPs), a traditional Chinese medicine used for thousands of years, is a potential neuroprotective polysaccharide via a relatively poorly understood mechanism. We previously reported that CPPs attenuated tau pathology in hTau transfected mice and therefore in the current work investigated the effect of CPPs on Aß toxicity and cognitive defects in APP/PS1 mice model. It was found that one-month intragastric administration of CPPs significantly ameliorated cognitive defects in APP/PS1 mice. In addition, CPPs treatment mitigated the loss of the synaptic plasticity and increased the synaptic proteins including synaptotagmin and PSD95. The expression of Aß42 and Aß40 was remarkably decreased in the hippocampus of APP/PS1 mice after CPPs treatment. We also found that CPPs coincubation significantly reduced the amount of APPß and Aß42 expression in cells. Intriguingly, the activity of BACE1 was decreased following CPPs treatment in both the hippocampus of APP/PS1 mice and in vitro experiments. Collectively, these results indicated that CPPs attenuated Aß pathology in APP/PS1 mice, and down-regulating BACE1 might be the underlaying mechanism which could be a therapeutic target for alleviating cognitive defects in AD pathology.