-
Ecotoxicology and Environmental Safety May 2024To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term...
To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term heavy metal compound pollution habitats, this study, in the Diaojiang river basin, which has been polluted by heavy metals(HMs) for nearly a thousand years, two Eucriotettix oculatus populations was collected from mining and non-mining areas. It was found that the contents of 7 heavy metals (As, Cd, Pb, Zn, Cu, Sn, Sb) in E. oculatus of the mining area were higher than that in the non-mining 1-11 times. The analysis of morphology shows that the external morphology, the hind wing type and the chromosomal morphology of E. oculatus are significant differences between the two populations. Based on the heavy metal accumulation,morphological change, and stable population density, it is inferred that the mining area population has been affected by heavy metals and has adapted to the environment of heavy metals pollution. Then, by analyzing the transcriptome of the two populations, it was found that the digestion, immunity, excretion, endocrine, nerve, circulation, reproductive and other systems and lysosomes, endoplasmic reticulum and other cell structure-related gene expression were suppressed. This shows that the functions of the above-mentioned related systems of E. oculatus are inhibited by heavy metal stress. However, it has also been found that through the significant up-regulation of genes related to the above system, such as ATP2B, pepsin A, ubiquitin, AQP1, ACOX, ATPeV0A, SEC61A, CANX, ALDH7A1, DLD, aceE, Hsp40, and catalase, etc., and the down-regulation of MAPK signalling pathway genes, can enhanced nutrient absorption, improve energy metabolism, repair damaged cells and degrade abnormal proteins, maintain the stability of cells and systems, and resist heavy metal damage so that E. oculatus can adapt to the environment of heavy metal pollution for a long time.
Topics: Animals; Metals, Heavy; Water Pollutants, Chemical; Grasshoppers; Environmental Monitoring; Mining; China; Adaptation, Physiological; Transcriptome; Rivers
PubMed: 38599159
DOI: 10.1016/j.ecoenv.2024.116301 -
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke... Feb 2024To explore the clinical characteristics of children with adenoid hypertrophy (AH) and laryngopharyngeal reflux (LPR) by detecting the expression of pepsin in adenoids...
To explore the clinical characteristics of children with adenoid hypertrophy (AH) and laryngopharyngeal reflux (LPR) by detecting the expression of pepsin in adenoids as a standard for AH with LPR. A total of 190 children who were admitted for surgical treatment due to AH were included in the study. The main clinical symptoms of the patients were recorded, and the degree of adenoid hypertrophy was evaluated. Before the surgery, Reflux Symptom Index (RSI) and Reflux Finding Score (RFS) were used to evaluate the reflux symptoms. After the surgery, pepsin immunohistochemical staining was performed on the adenoid tissue, and according to the staining results, the patients were divided into study group (pepsin staining positive) and control group (pepsin staining negative). SPSS 19.0 software was used for statistical analysis. Quantitative data conforming to normal distribution between the two groups were tested by two-independent sample test, and quantitative data with skewed distribution were tested by test. The positive rate of pepsin staining in the 190 AH patients was 78.4% (149/190). The study group had higher levels of preoperative symptoms such as erythema and/or congestion of the pharynx(2.1±0.7 . 1.8±0.6,=2.23), vocal cord edema[1.0(0, 1.0) . 1.0(0, 1.0), =2.00], diffuse laryngeal edema[0(0, 1.0) . 0(0, 0), =2.48], posterior commissure hypertrophy[(1.4±0.6 . 1.1±0.5), =2.63], and a higher total score on the RFS scale than the control group(6.2±2.7 . 5.0±2.6, =2.47), with statistical differences (<0.05). The sensitivity and specificity of RFS score in diagnosing AH with LPR were 24.8% and 80.5%, respectively. When RFS>5 was used as the positive threshold, the sensitivity and specificity of RFS score in diagnosing AH with LPR were 61.1% and 58.5%, respectively. There was a statistical difference in the number of positive cases of RFS score between the study group and the control group(91 17,χ=5.04,=0.032). LPR is common in AH children. Children with AH and LPR have specific performance in electronic laryngoscopy, such as erythema with edema in the pharynx, posterior commissure hypertrophy, and vocal cord edema.
Topics: Child; Humans; Adenoids; Pepsin A; Laryngopharyngeal Reflux; Laryngeal Edema; Edema; Hypertrophy; Erythema
PubMed: 38369792
DOI: 10.3760/cma.j.cn115330-20231221-00318 -
Journal of Medicinal Food May 2024The principal mechanisms surrounding gastrointestinal (GI) side effects due to chemotherapy are unclear, whereas the information regarding symptom management of patients...
The principal mechanisms surrounding gastrointestinal (GI) side effects due to chemotherapy are unclear, whereas the information regarding symptom management of patients with esophageal cancer post-esophagectomy is lacking. Esophagectomy patients are left with significant anatomical changes to the GI tract, including the cutting of the vagus nerve, which regulates gastric secretions, gastric acid pH, and motility. A 76-year-old male patient self-referred himself to the clinical dietitian for nutritional management of chronic nausea, fatigue, weight loss, and dumping syndrome 9 months post-esophagectomy, which was not responsive to medications. A physical functional nutritional assessment with evaluation of diet history and elimination suggested gastric hypochlorhydria. Gastric acid is needed for the active absorption of iron, zinc, B complex vitamins, especially B12, and digestion of consumed proteins. A digestive supplement, betaine hydrochloric acid with pepsin (BHClP), was introduced, and the patient ingested 1 capsule containing 500 mg betaine hydrochloride and 23.5 mg pepsin prior to protein-containing meals and reported a substantial decrease in GI symptoms while eating a regular diet with no limitations. He gained necessary weight and energy for daily activities. After a few months, the patient discontinued BHClP, and GI symptoms and dumping syndrome returned, leading to a loss of 7.5% of his body weight. The patient reinitiated the supplement and GI symptoms dissipated, and weight was restored. BHClP provided metabolic therapeutic benefit to optimize the patient's oral intake, preventing further complications and malnutrition. The success with BHClP for this patient case suggests that more research is needed to fully realize the mechanisms and clinical usage.
Topics: Humans; Male; Aged; Esophageal Neoplasms; Betaine; Pepsin A; Dumping Syndrome; Dietary Supplements; Esophagectomy
PubMed: 38695854
DOI: 10.1089/jmf.2023.0174 -
Food Research International (Ottawa,... May 2024Konjac glucomannan (KGM) can significantly prolong gastrointestinal digestion. However, it is still worth investigating whether the macromolecular crowding (MMC) induced...
The effect of konjac glucomannan on enzyme kinetics and fluorescence spectrometry of digestive enzymes: An in vitro research from the perspective of macromolecule crowding.
Konjac glucomannan (KGM) can significantly prolong gastrointestinal digestion. However, it is still worth investigating whether the macromolecular crowding (MMC) induced by KGM is correlated with digestion. In this paper, the MMC effect was quantified by fluorescence resonance energy transfer and microrheology, and the digests of starch, protein, and oil were determined. The digestive enzymes were analyzed by enzyme reaction kinetic and fluorescence quenching. The results showed that higher molecular weight (604.85 ∼ 1002.21 kDa) KGM created a larger MMC (>0.8), and influenced the digestion of macronutrients; the digests of starch, protein, and oil all decreased significantly. MMC induced by KGM decreased the Michaelis-Menten constants (K and V) of pancreatic α-amylase (PPA), pepsin (PEP), and pancreatic lipase (PPL). The larger MMC (>0.8) induced by KGM resulted in the decrease of fluorescence quenching constants (K) in PPA and PPL, and the increase of K in PEP. Therefore, varying degrees of MMC induced by KGM could play a role in regulating digestion and the inhibitory effect on digestion was more significant in a relatively more crowded environment induced by KGM. This study provides theoretical support for the strategies of nutrient digestion regulation from the perspective of MMC caused by dietary fiber.
Topics: Spectrometry, Fluorescence; Mannans; Pepsin A; Macromolecular Substances; Pancreatic alpha-Amylases; Starch
PubMed: 38609226
DOI: 10.1016/j.foodres.2024.114247 -
Food Chemistry May 2024Application of nanomaterials (NMs) in agriculture poses an ingestion risk to humans and may affect the digestive process. Different fates of NMs with differential...
Application of nanomaterials (NMs) in agriculture poses an ingestion risk to humans and may affect the digestive process. Different fates of NMs with differential charges in the gastrointestinal tract should be considered. In this study, the interaction between three carbon dots (CDs) carried with different functional groups (-NH, -OH, and -COOH) and pepsin was analyzed through an in vitro digestion model. The results showed that CDs significantly reduced pepsin activity. Among them, CDs-NH had the greatest effect, following by CDs-OH, and CDs-COOH. Besides, molecular docking demonstrated the specific binding site of CDs to pepsin, while the most stable binding energy (-8.10 kcal/mol) was formed between CDs-NH and pepsin. Further, CDs formed a nanomaterial-protein crown structure with pepsin. The present study enriches the functional group properties of CDs in the digestion and provides new ideas for the potential human health of NMs.
Topics: Humans; Pepsin A; Carbon; Molecular Docking Simulation; Binding Sites; Digestion; Quantum Dots
PubMed: 38134824
DOI: 10.1016/j.foodchem.2023.138224 -
Journal of Biomolecular Structure &... Nov 2023Sulfate polysaccharides can inhibit DNA digestion in simulated gastric juice , which is important for regulating dietary nucleic acids metabolism, but the mechanism of...
Sulfate polysaccharides can inhibit DNA digestion in simulated gastric juice , which is important for regulating dietary nucleic acids metabolism, but the mechanism of inhibition is unclear. This study used dextran sulfate (DS) with different sulfate groups and molecular weights to explore the effect of DS on DNA digestion. Molecular interactions between DS and DNA were investigated by biolayer interferometry (BLI), isothermal titration calorimetry (ITC) and molecular dynamics simulations. Results indicated that DS with higher molecular weight and sulfate group content showed stronger inhibitory effect of DNA digestion. ITC results showed that the combined K value of DNA and DS was about 2.53 mM. The main reason for inhibition of DNA digestion is that the formation of hydrogen bonds between the sulfate group of DS and DNA bases hinders the binding of DNA to pepsin. This finding will facilitate new strategies for nucleic acid metabolism and oral drug delivery.Communicated by Ramaswamy H. Sarma.
PubMed: 37975333
DOI: 10.1080/07391102.2023.2283145 -
International Journal of Biological... Feb 2024The substantial nutritional content and diversified biological activity of plant-based nutraceuticals are due to polyphenolic chemicals. These chemicals are important...
Study of an inhibitory effect of plant polyphenolic compounds against digestive enzymes using bench-working experimental evidence predicted by molecular docking and dynamics.
The substantial nutritional content and diversified biological activity of plant-based nutraceuticals are due to polyphenolic chemicals. These chemicals are important and well-studied plant secondary metabolites. Their protein interactions are extensively studied. This relationship is crucial for the logical development of functional food and for enhancing the availability and usefulness of polyphenols. This study highlights the influence of protein types and polyphenols on the interaction, where the chemical bindings predominantly consist of hydrophobic interactions and hydrogen bonds. The interaction between polyphenolic compounds (PCs) and digestive enzymes concerning their inhibitory activity has not been fully studied. Therefore, we have examined the interaction of four digestive enzymes (α-amylase, pepsin, trypsin, and α-chymotrypsin) with four PCs (curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone) through in silico and in vitro approaches. In vitro plate assays, enzyme kinetics, spectroscopic assays, molecular docking, and simulations were performed. We observed all these PCs have significant docking scores and preferable interaction with the active site of the digestive enzymes, resulting in the reduction of enzyme activity. The enzyme-substrate binding mechanism was determined using the Lineweaver Burk plot, indicating that the inhibition occurred competitively. Among four PCs diosmin and morin has the highest interaction energy over digestive enzymes with IC value of 1.13 ± 0.0047 and 1.086 ± 0.0131 μM. Kinetic studies show that selected PCs inhibited pepsin, trypsin, and chymotrypsin competitively and inhibited amylase in a non-competitive manner, especially by 2',3',4'-trihydroxychalcone. This study offers insights into the mechanisms by which the selected PCs inhibit the enzymes and has the potential to enhance the application of curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone as natural inhibitors of digestive enzymes.
Topics: Molecular Docking Simulation; Pepsin A; Trypsin; Curcumin; Kinetics; Diosmin; Polyphenols; Flavonoids; alpha-Amylases; alpha-Glucosidases
PubMed: 38185307
DOI: 10.1016/j.ijbiomac.2024.129222 -
Food Research International (Ottawa,... Jun 2024In this paper, the effect of monosodium glutamate (MSG) on coconut protein (CP) solubility, surface hydrophobicity, emulsification activity, ultraviolet spectroscopy and...
In this paper, the effect of monosodium glutamate (MSG) on coconut protein (CP) solubility, surface hydrophobicity, emulsification activity, ultraviolet spectroscopy and fluorescence spectroscopy was investigated. Meanwhile, the changes in the in vitro digestive properties of coconut milk were also further analyzed. MSG treatment altered the solubility and surface hydrophobicity of CP, thereby improving protein digestibility. Molecular docking showed that CP bound to pepsin and trypsin mainly through hydrogen bonds and salt bridges. And MSG increased the cleavable sites of pepsin and trypsin on CP, thus further improving the protein digestibility. In addition, MSG increased the Na concentration in coconut milk, promoted flocculation and aggregation between coconut milk droplets, which prevented the binding of lipase and oil droplets and inhibited lipid digestion. These findings may provide new ideas and insights to improve the digestive properties of plant-based milk.
Topics: Sodium Glutamate; Digestion; Cocos; Hydrophobic and Hydrophilic Interactions; Solubility; Molecular Docking Simulation; Plant Proteins; Trypsin; Pepsin A
PubMed: 38658074
DOI: 10.1016/j.foodres.2024.114288 -
Langmuir : the ACS Journal of Surfaces... Jan 2024Proteolytic enzymes play a pivotal role in the industry. Still, because of denaturation, the extensive applicability at their level of best catalytic efficiency over a...
Chemically Bonded Pepsin via Its Inert Center to Diazo Functionalized Silica Gel through Multipoint Attachment Mode: A Way of Restoring Biocatalytic Sustainability over "Wider pH" Range.
Proteolytic enzymes play a pivotal role in the industry. Still, because of denaturation, the extensive applicability at their level of best catalytic efficiency over a more comprehensive pH range, particularly in alkaline conditions over pH 8, has not been fully developed. On the other hand, enzyme immobilization following a suitable protocol is a long pending issue that determines the conformational stability, specificity, selectivity, enantioselectivity, and activity of the native enzymes at long-range pH. As a bridge between these two findings, in an attempt at a freezing temperature 273-278 K at an alkaline pH, the diazo-functionalized silica gel (SG) surface has been used to rapidly diazo couple pepsin through its inert center, the -carbon of the phenolic -OH of surface-occupied Tyr residues in a multipoint mode: when all the various protein groups, viz., amino, thiol, phenol, imidazole, carboxy, etc., in the molecular sequence including those belonging to the active sites, remain intact, the inherent inbuilt interactions among themselves remain. Thereby, the macromolecule's global conformation and helicity preserve the status quo. The dimension of the SG-enzyme conjugate confirms as {Si(OSi) (HO)} {-O-Si(CH)-O-CH-N═N}·{pepsin}·HO; where the values of and have been determined respectively as 347 and 188. The material performs the catalytic activity much better at 7-8.5 than at pH 2-3.5 and continues for up to six months without any appreciable change.
Topics: Pepsin A; Silica Gel; Enzymes, Immobilized; Proteins; Hydrogen-Ion Concentration; Enzyme Stability
PubMed: 38240266
DOI: 10.1021/acs.langmuir.3c03113 -
Food Chemistry Jan 2024Ruminant milk is known to coagulate into structured clots during gastric digestion. This study investigated the movements of moisture and acid in skim milk clots formed...
Ruminant milk is known to coagulate into structured clots during gastric digestion. This study investigated the movements of moisture and acid in skim milk clots formed during dynamic gastric digestion and the effects of milk type (regular or calcium-rich) and the presence/absence of pepsin. We conducted hyperspectral imaging analysis and successfully modelled the moisture contents based on the spectral information using partial least squares regression. We generated prediction maps of the spatiotemporal distribution of moisture within the samples at different stages of gastric digestion. Simultaneously to acid uptake, the moisture in the milk clots tended to decrease over the digestion time; this was significantly promoted by pepsin. Moisture mapping by hyperspectral imaging demonstrated that the high and low moisture zones were centralized within the clot and at the surface respectively. A structural compaction process promoted by pepsinolysis and acidification probably contributed to the water expulsion from the clots during digestion.
Topics: Animals; Milk; Pepsin A; Hyperspectral Imaging; Stomach; Acids; Digestion
PubMed: 37586231
DOI: 10.1016/j.foodchem.2023.137094