Arginine Content Research Articles

EVALUATION OF THE QUALITY OF WHOLE GRAINS AND LEGUMES

Grain products are a fundamental element in ensuring food security for the population. In recent years, the demand for whole grain products has significantly increased. Whole grain products are highly nutritious due to their balanced content of amino acids and other macro- and microelements. The aim of this study is to investigate the chemical and amino acid composition of whole grain raw materials such as triticale grain of the «Dauren» variety, buckwheat grain of the «Dikul» variety, and lentil grains of the «Sakura» and «Shyrayly» varieties. The chemical research revealed that whole leguminous crops have a high protein content, which is approximately twice as high as that of whole grains, with protein content values of 28,75% and 24,67%, respectively. The analysis of the conducted studies showed that the amino acid composition of the proteins in whole grains and whole leguminous crops is characterized by a high content of essential amino acids. Leguminous crops have a higher content of arginine and lysine compared to whole grains. Whole leguminous crops have a higher protein content than whole grains, making them important for increasing the nutritional value of food products when mixed. Additionally, various processing methods and their effects on preserving nutritional properties were studied.

Influence of different doses of essential amino acids on growth and development of broiler chickens

Optimization of the amino acid balance of essential amino acids, as well as individual amino acids and probiotics, allows improving production indicators such as poultry livability, live weight gain, feed conversion and increasing the economic efficiency of meat production. The purpose of the research was to evaluate the eff ect of diff erent levels of arginine in poultry diets on average daily live weight gain and determine its effect on the livability of broiler chickens, optimize the amino acid composition of broiler chicken diets in accordance with the recommended standards of essential amino acids. The experiment was conducted at Kuratye LLC in Verkhniy Tagil in the Sverdlovsk region on the cross Arbor Acres of broiler chickens. The diet of the experimental group of broilers diff ered from the control diet in that the content of the amino acid arginine was brought to the standards recommended by German poultry farmers. It was found that the average daily live weight gain of broilers in the experimental group for the entire growing period was 47.7 g in the control group, in the experimental group it was 9.0 % higher than in the control and was 52.0 g. The European productivity index, calculated taking into account live weight, livability, fattening period of poultry and costs per unit of production in the control group was 274.0, and in the experimental group it was 309.2 units. From the conducted studies it follows that it is necessary to take into account the ratio of arginine to lysine in the diets of broiler chickens at the level of 1.04, 1.06 and 1.07, respectively, for the rearing phases such as starting, growth and finishing periods.

Transcriptomic profiling reveals the effect of amino acid metabolism on the production capacity of Volvariella volvacea during repeated subculture

Tissue separation is commonly employed for the purification and rejuvenation of edible mushroom species. However, repeated or continuous tissue separation can result in strain degradation. In this study, cultivation experiments were conducted in Volvariella volvacea V844 (T0). Tissue separation subculture was repeated 16 times to obtain the succession strains T1–T16. Of these, T4, T8, T12, and T16 were selected as experimental strains, and their production traits were evaluated. Additionally, transcriptome sequencing technology was used to analyze the transcription spectrum of these strains. The results showed that with the increase in subculture cycles, the colony diameter, mycelial growth rate, mycelial biomass, and biological efficiency of V. volvacea first increased and then decreased, and the growth cycle was gradually prolonged. Transcriptome sequencing revealed the presence of 1375, 1015, 651, and 1648 differentially expressed genes (DEGs) in T4, T8, T12, and T16, respectively, versus T0. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis demonstrated that these DEGs were mainly involved in amino acid metabolic pathways. Further annotation analysis revealed that in V. volvacea subculture strains, the number of DEGs involved in histidine metabolism (Ko00340) and arginine and proline metabolism (Ko00330) was the highest. Amino acid analysis demonstrated that the proline and arginine content first rose and then fell across successive subculture strains, whereas the histidine content first decreased and then increased. The results indicated that the change in the production capacity of V. volvacea during repeated subculture may be due to the altered expression of DEGs involved in amino acid metabolism, leading to changes in the amino acid content of V. volvacea and further affecting the accumulation of reactive oxygen species, free radical scavenging, energy acquisition, nutrient absorption, and redox balance. These changes could result in the rejuvenation (<8) of the V. volvacea strain or cause its degradation (>12). The results of this study provide a theoretical framework for studying the mechanisms of rejuvenation and degradation in V. volvacea and also offer insights valuable for studying the molecular functions of genes involved in the growth of V. volvacea and other edible fungi.

Characterization of high protein soybean using mass spectrometry based proteomic and metabolomic analyses.

We have created several high protein (HPBL) and low protein breeding lines (LPBL) by crossing between NC-Raleigh and PI407228. The NC-Raleigh is a low protein cultivar widely grown in North Carolina with excellent yield potential and a high protein wild soybean (Glycine soja) with low yield. We analyzed the F6 generation of this cross for protein and oil compositions using near-infrared spectroscopy (NIR). Two soybean lines HPBL and LPBL were selected for biochemical analysis using mass spectrometry-based proteomic and metabolomic techniques. We identified 4,538 proteins and 267 metabolites in these lines. The HPBL showed the enrichment of proteins associated with protein synthesis, processing, and storage in addition to higher content of primary and secondary metabolites. The mapping of metabolites on the global metabolic pathways revealed the increased protein content in the HPBL that may have resulted from increased arginine content routed from citrulline-argininosuccinic acid. This information will be useful for breeders and biotechnologists to produce a value-added soybean trait.

Effect of symbiotic microbiota and arginine on host plant selection by the tea green leafhopper in tea cultivation

The tea green leafhopper (TGLH), Empoasca (Matsumurasca) onukii Matsuda, poses a significant challenge to tea cultivation in East Asia because of its ability to infest specific tea plant cultivars. Here, we investigated the complex interactions between TGLHs, various tea cultivars, and their symbiotic microbiota, especially the effect of arginine on host selection. A detailed two-year field study involving 16 tea cultivars, coupled with controlled laboratory and field experiments, was conducted to establish a clear link between TGLH infestation and the arginine content of tea plants. Metagenomic analysis revealed a predominance of bacterial taxa in TGLHs, primarily from the phylum Proteobacteria, with significant contributions from orders such as Pseudomonadales, Enterobacterales, and Flavobacteriales, which are crucial for the biosynthesis of essential amino acids but lack the argF gene necessary for arginine synthesis. The absence of the argF gene indicates the potential presence of microbial-mediated dietary adaptation strategies in TGLHs. Additionally, our research examines microbial diversity within TGLH populations and confirms the critical role that symbiotic bacteria play in influencing dietary preferences. The results of our study provide insights into the dynamic interplay between pests, plants, and microorganisms. Our findings are preliminary, and further research is needed to explore the potential applications of symbiotic bacteria in sustainable tea cultivation and integrated pest management strategies.

Fusion of spectra and texture features of hyperspectral imaging for quantification and visualization of characteristic amino acid contents in beef

Characteristic amino acids is an important indicator for evaluating the nutritional value and flavor parameter of beef. To accurately quantify and visualize of arginine and alanine content in beef, the feasibility of visible near-infrared hyperspectral multivariate calibration analysis and data fusion was explored. Three methods were used to select the optimal feature wavelength and fusion multi-level texture information, and to develop the prediction performance of linear, non-linear and neural network models in different signals. Compared to all models, the linear model demonstrated superior performance in terms of characteristic spectral and fused spectral. Among, the more effective prediction performances emerged from CARS-ASM-ENT-PLSR model with RP2 = 0.9211, RMSEP = 0.1252 mg/100 g and RPDp = 3.49 for alanine. The UVE-ASM-ENT-HOM-COR-PLSR model for arginine prediction achieved a good performance of RP2 = 0.8596, RMSEP = 0.8596 mg/100 g and RPDp = 2.62. Finally, visualization plots of arginine and alanine content distribution were generated. This study shows that the data fusion method provides a new approach for rapid evaluation of CAA content.

Effects of Bacillus subtilis-fermented soybean meal replacing fish meal on antioxidant activity, immunity, endoplasmic reticulum stress and hepatopancreas histology in Pacific white shrimp (Litopenaeus vannamei)

IntroductionScreening excellent bacterial strains for fermentation is the key to improving the nutritional value and bioavailability of soybean meal (SBM). This study investigated the application of Bacillus subtilis-fermented soybean meal (FSBM) on the feed of Pacific white shrimp (Litopenaeus vannamei).MethodsFSBM was used to replace 0%, 25%, 50%, 75%, and 100% fish meal, and the feeding trial was lasted for 8 weeks (initial weight: 0.9 g). Results and discussionThe amino acid profile in the whole shrimp body was tested. FSBM substitution only significantly reduced the content lysine in whole shrimp body, but increased the content of arginine. Fatty acid data showed that the content of n-6 PUFAs in whole shrimp was significantly increased by FSBM substitution. In muscle, FSBM substitution significantly reduced the content of MUFAs, but increased the content of PUFAs including C18:3n-3, C18:2n-6 and C20:4n-6. No hepatopancreas structure modifications appeared in the 25% group compared with the control group. Subsequently, we investigated the response patterns of different organs to FSBM substitution from antioxidant, endoplasmic reticulum stress and immunity. A high proportion of FSBM significantly reduced the content of GSH in hemolymph and hepatopancreas, while increased the mRNA expression of cat. FSBM substitution did not affect the activities of antioxidant enzymes in the intestine. However, the mRNA expression level of hsp70 in the intestine was significantly reduced by FSBM. In terms of immunity, the mRNA expression levels of lgbp and penaeidin in the hepatopancreas showed a significant linear increase trend. In muscle, high proportion of FSBM significantly increased the mRNA expression of imd. FSBM substitution did not significantly affect the expression of immune genes in the intestine. In terms of endoplasmic reticulum stress, FSBM substitution significantly increased the mRNA expression of eif2α in the hepatopancreas. In muscle, FSBM substitution inhibited the mRNA expression of bip. In the intestine, FSBM replacing 75% of fish meal significantly increased the mRNA expression of bip and ire1. In summary, this study indicated that when the fish meal content account for 40% in diets (dry weight), the screened Bacillus subtilis-FSBM can replace 25% of fish meal protein without reducing the antioxidant and immune abilities of shrimp.

Exogenous inoculation with heavy metal-immobilizing bacteria roused the key rhizosphere bacterial community and metabolites of wheat to inhibit cadmium absorption

Rhizosphere functional microorganisms play an important role in the bioremediation of heavy metal-polluted farmlands, however, further research is needed to investigate the effects of exogenous inoculation of functional strains on key bacterial communities and metabolites in cadmium (Cd)-polluted wheat farmlands. This study investigated the effects of the urease-producing bacterium Enterobacter bugandensis TJ6 combined with polyamine-producing bacterium Serratia marcescens X43 on Cd uptake by wheat and its microbiological and soi biolological mechanisms. The results showed that strains TJ6+X43 reduced (95.1 %) the Cd content by secreting urease and polyamines and inducing the precipitation of Cd to form CdCO3 and Cd(OH)2. The combined strains increased (22.7 %) the dry weight and reduced (37.2 %) the Cd content in wheat grains. Moreover, the DTPA-Cd content, the NH4+/NO3- ratio and the urease activity were increased in the presence of strains TJ6+X43. The combined strains reduced the diversity of bacterial communities, but increased the relative abundances of key strains such as Gemmatimonas, Ramlibacter, Sporacetigenium, Pseudomonas, Microvirga, and Nitrospira in the wheat rhizosphere soil. In addition, the contents of glutamate, glutathione, L-ribulose, arginine, nitrite, spermine, isocitrate, and D-xylulose were also increased. More importantly, glutamate metabolism was roused to induce rhizosphere metabolites and functional bacterial communities to synergistically inactivate Cd. The results showed that inoculation with heavy metal-immobilizing bacteria can result in the activation of key functional bacteria and the regulation of metabolite production in wheat rhizosphere soil to immobilize heavy metals, which has broad potential in the bioremediation of wheat fields and ensuring food security.

Identification and Characterization of Polyamine Metabolism in Citrus in Response to 'Candidatus Liberibacter asiaticus' Infection.

Citrus Huanglongbing, one of the most devastating citrus diseases, is caused by 'Candidatus Liberibacter asiaticus' (CLas). Polyamines are aliphatic nitrogen-containing compounds that play important roles in disease resistance and are synthesized primarily by two pathways: an arginine decarboxylation pathway and an ornithine decarboxylation pathway. However, it is unclear whether polyamines play a role in the tolerance of citrus to infection by CLas and, if so, whether one or both of the core polyamine metabolic pathways are important. We used high-performance liquid chromatography and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry to detect the contents of nine polyamine metabolism-related compounds in six citrus cultivars with varying levels of tolerance to CLas. We also systematically detected the changes in polyamine metabolism-related compounds and H2O2 contents and compared the gene expression levels and the activities of enzymes involved in the polyamine metabolic pathway among healthy, asymptomatic, and symptomatic leaves of Newhall navel oranges infected with CLas. The tolerant and moderately tolerant varieties showed higher polyamine metabolism-related compound levels than those of susceptible varieties. Compared with the healthy group, the symptomatic group showed significantly increased contents of arginine, ornithine, γ-aminobutyric acid, and putrescine by approximately 180, 19, 1.5, and 0.2 times, respectively, and upregulated expression of biosynthetic genes. Arginase and ornithine decarboxylase enzyme activities were the highest in the symptomatic group, whereas arginine decarboxylase and agmatine deiminase enzyme activities were the highest in the asymptomatic group. The two polyamine biosynthetic pathways showed different trends with the increase of the CLas titer, indicating that polyamines were mainly synthesized through the arginine decarboxylase pathway in the asymptomatic leaves and were synthesized via the ornithine decarboxylase pathway in symptomatic leaves. These findings provide new insight into the changes in polyamine metabolism in citrus infected with CLas.

Integrated transcriptomics and metabolomics study of embryonic breast muscle of Jiaji ducks

Because number of matured muscle fibers in poultry does not increase after birth, the meat yield is mainly determined during embryogenesis. We previously indicated breast muscle grew rapidly from 18th day after hatching (E18) to E27, and almost stopped from E27 to E34 of Jiaji ducks, while the mechanism is unclear. This study utilized RNA-seq to explore the related genes of muscle development and their relationship with small molecule metabolites at E18, E27 and E34 of Jiaji ducks. Several thousand differentially expressed genes (DEGs) were detected among E18, E27 and E34. DEGs expression profiles included 8 trend maps, among which trend 1 was opposite to and trend 6 was consistent with breast muscle development trend of Jiaji ducks. Through joint analysis between trend 1 of DEGs and trend 1 of differential metabolites (DEMs), protein digestion and absorption pathway stood out. The decrease of COL8A2 gene expression will lead to the decrease of arginine content, which will inhibit the development of breast muscle in embryonic Jiaji duck. Similarly, joint analysis between trend 6 of DEGs and trend 6 of DEMs indicated the increase of GAMT gene expression will cause the increase of proline content, and then promote the development of breast muscle of Jiaji duck in embryonic period. These results will be helpful for further understanding the mechanism of muscle yields of Jiaji ducks.

Metabolic Effects of Short-Term High-Fat Intake Vary Depending on Dietary Amino Acid Composition

BackgroundIt is generally accepted that excessive fat intake has undesirable effects on the energy metabolism of our body. Dietary amino acid composition is also critical to the regulation of lipid metabolism. ObjectivesThis study aimed to investigate whether high-fat diets (HFDs) with different amino acid deficiencies lead to different metabolic outcomes. MethodsSix-wk-old male Wistar rats were fed either a control diet (CN; 3.7 kcal/g, 12% calories from fat) or HFDs (5.1 kcal/g, 60% calories from fat) with 7 different amino acid compositions [control or methionine, arginine, histidine, lysine, threonine, or branched-chain amino acids (BCAAs) deficient], for 7 d. Tissue weights and lipid accumulation in the liver, skeletal muscle, and adipose tissue were measured, and serum biochemical parameters were analyzed. ResultsAlthough the food intake of the HFD groups was a little less than that of the CN group, the total calorie intakes were comparable among the groups, except for histidine-deficient and BCAA-deficient groups. In rats fed am HFD with a control amino acid composition (HFCN), dramatic increase in triglyceride (TG) accumulation in the liver and serum LDL cholesterol concentration were observed compared with the CN group. However, when the arginine content in the diet was reduced, liver TG accumulation was completely inhibited, with no apparent effects on serum lipoprotein-cholesterol concentrations. Meanwhile, deficiency of the other amino acids, such as threonine, reversed HFD-induced upregulation of serum LDL cholesterol. ConclusionsIt is observed that although the rats ingested an excessive amount of fat, neither ectopic fat accumulation nor dyslipidemia were always induced at least in the short term; hence, the consequent metabolic change was dependent on the dietary amino acid composition. These findings introduce an important perspective regarding HFD regimens in both scientific and clinical contexts.

Portulaca oleracea exhibited anti-coccidian activity, fortified the gut microbiota of Hu lambs

Coccidia of the genus Eimeria are important pathogens that cause coccidiosis in livestock and poultry. Due to the expansion of intensive farming, coccidiosis has become more difficult to control. In addition, the continued use of anti-coccidiosis drugs has led to drug resistance and residue. Some herbs used in traditional Chinese medicine (TCM) have been shown to alleviate the clinical symptoms of coccidiosis, while enhancing immunity and growth performance (GP) of livestock and poultry. Previous in vitro and in vivo studies have reported that the TCM herb Portulaca oleracea exhibited anti-parasitic activities. In total, 36 female Hu lambs were equally divided into six treatment groups: PL (low-dose P. oleracea), PH (high-dose P. oleracea), PW (P. oleracea water extract), PE (P. oleracea ethanol extract), DIC (diclazuril), and CON (control). The treatment period was 14 days. The McMaster counting method was used to evaluate the anti-coccidiosis effects of the different treatments. Untargeted metabolomics and 16S rRNA gene sequencing were used to investigate the effects of treatment on the gut microbiota (GM) and GP. The results showed that P. oleracea ameliorated coccidiosis, improved GP, increased the abundances of beneficial bacteria, and maintained the composition of the GM, but failed to completely clear coccidian oocysts. The Firmicutes to Bacteroides ratio was significantly increased in the PH group. P. oleracea increased metabolism of tryptophan as well as some vitamins and cofactors in the GM and decreased the relative content of arginine, tryptophan, niacin, and other nutrients, thereby promoting intestinal health and enhancing GP. As an alternative to the anti-coccidiosis drug DIC, P. oleracea effectively inhibited growth of coccidia, maintained the composition of the GM, promoted intestinal health, and increased nutrient digestibility.

“Rich arginine and strong positive charge” antimicrobial protein protamine: From its action on cell membranes to inhibition of bacterial vital functions

Protamine, an antimicrobial protein derived from salmon sperm with a molecular weight of approximately 5 kDa, is composed of 60–70 % arginine and is a highly charged protein. Here, we investigated the mechanism of antimicrobial action of protamine against Cutibacterium acnes (C. acnes) focusing on its rich arginine content and strong positive charge. Especially, we focused on the attribution of dual mechanisms of antimicrobial protein, including membrane disruption or interaction with intracellular components. We first determined the dose-dependent antibacterial activity of protamine against C. acnes. In order to explore the interaction between bacterial membrane and protamine, we analyzed cell morphology, zeta potential, membrane permeability, and the composition of membrane fatty acid. In addition, the localization of protamine in bacteria was observed using fluorescent-labeled protamine. For investigation of the intracellular targets of protamine, bacterial translation was examined using a cell-free translation system. Based on our results, the mechanism of the antimicrobial action of protamine against C. acnes is as follows: 1) electrostatic interactions with the bacterial cell membrane; 2) self-internalization into the bacterial cell by changing the composition of the bacterial membrane; and 3) inhibition of bacterial growth by blocking translation inside the bacteria. However, owing to its strong electric charge, protamine can also interact with DNA, RNA, and other proteins inside the bacteria, and may inhibit various bacterial life processes beyond the translation process.

Exploring the dietary and therapeutic potential of licorice (Glycyrrhiza uralensis Fisch.) sprouts.

Ethnopharmacological relevanceThis research substantiates the traditional use of Glycyrrhiza uralensis Fisch. for liver health, with scientific evidence of the non-toxic and lipid-lowering properties of licorice sprout extracts. The sprouts' rich mineral and amino acid content, along with their strong antioxidant activity, reinforce their value in traditional medicine. These findings bridge ancient herbal practices with modern science, highlighting licorice's potential in contemporary therapeutic applications. Aim of the studyThe study aimed to investigate the dietary and medicinal potential of G. uralensis sprouts by assessing their safety, nutritional content, and antioxidant properties using both plant and animal models. Specifically, the study sought to determine the effects of different sizes of licorice sprouts on lipid metabolism in human liver cancer cells and their overall impact on rat health indicators. Materials and methodsThe study examined the effects of aqueous and organic extracts from G. uralensis sprouts of varying lengths on the cytotoxicity, lipid metabolism, and antioxidant activity in HepG2 cells, alongside in vivo impacts on Sprague-Dawley rats, using MTT, ICP, and HPLC. It aimed to assess the potential health benefits of licorice sprouts by analyzing their protective effects against oxidative stress and their nutritional content. ResultsLicorice sprout extracts from G. uralensis demonstrated no cytotoxicity in HepG2 cells, significantly reduced lipid levels, and enhanced antioxidant activities, with the longest sprouts (7 cm) showing higher mineral, sugar, and arginine content as well as increased glycyrrhizin and liquiritigenin. In vivo studies with Sprague-Dawley rats revealed weight gain and improved antioxidant enzyme activities in blood plasma and liver tissues after consuming the extracts, highlighting the sprouts' dietary and therapeutic potential. ConclusionsThis study is the first to demonstrate that G. uralensis sprouts, particularly those 7 cm in length, have no cytotoxic effects, reduce lipids, and have high mineral and antioxidant contents, offering promising dietary and therapeutic benefits.

Comparison of Body Characteristics, Carotenoid Composition, and Nutritional Quality of Chinese Mitten Crab (Eriocheir sinensis) with Different Hepatopancreas Redness.

In this study, we investigated the body characteristics, carotenoid composition, and nutritional quality of Eriocheir sinensis with different hepatopancreas redness (a*). We distributed the crabs into two groups based on the hepatopancreas a* values and compared their body characteristics, chroma, carotenoid composition, and protein, lipid, total sugar, amino acid, and fatty acid content via paired t-test. The results revealed that the relationships between hepatopancreas a* values and crab quality are sex specific. In female crabs, the differences in nutritional characteristics were evident mainly in the hepatopancreases and ovaries. In the redder hepatopancreases, the content of zeaxanthin and β-carotene increased, and the levels of C22:6n3 and C20:5n3 decreased (p < 0.05). In the ovaries, the content of astaxanthin, canthaxanthin, β-carotene, umami, and sweet amino acids were lower in the redder hepatopancreas crabs (p < 0.05). In male crabs, there were positive relationships between hepatopancreas a* and amino acid and fatty acid content. The content of leucine, arginine, and total umami amino acids in muscles and of unsaturated fatty acids and n-6 polyunsaturated fatty acids in hepatopancreases and testicles increased with increasing hepatopancreas a* values (p < 0.05). Therefore, the redder the hepatopancreas, the higher the nutritional quality of male crabs.

Regulation of Sacha Inchi protein on fecal metabolism and intestinal microorganisms in mice.

With the increasing demand for protein utilization, exploring new protein resources has become a research hotspot. Sacha Inchi Protein (SIP) is a high-quality plant protein extracted from Sacha Inchi meal. This study aimed to investigate the impact of SIP on mouse metabolomics and gut microbiota diversity and explore the underlying pathways responsible for its health benefits. In this study, the structural composition of SIP was investigated, and the effects of SIP on fecal metabolomics and intestinal microorganisms in mice were explored by LC-MS metabolomics technology analysis and 16S rRNA gene sequencing. The results showed that SIP was rich in amino acids, with the highest Manuscript Click here to view linked References content of arginine, which accounted for 22.98% of the total amino acid content; the potential fecal metabolites of mice in the SIP group involved lipid metabolism, sphingolipid metabolism, arginine biosynthesis, and amino acid metabolism; SIP altered the microbial composition of the cecum in mice, decreased the Firmicutes/Bacteroidetes value, and It decreased the abundance of the harmful intestinal bacteria Actinobacteriota and Desulfobacterota, and increased the abundance of the beneficial intestinal bacteria Faecalibaculum, Dubosiella. In conclusion, SIP is a high-quality plant protein with great potential for development in lipid-lowering, intestinal health, and mental illness, providing valuable clues for further research on its health-promoting mechanisms.

Cell-Penetrating and Enzyme-Responsive Peptides for Targeted Cancer Therapy: Role of Arginine Residue Length on Cell Penetration and In Vivo Systemic Toxicity.

For the improved delivery of cancer therapeutics and imaging agents, the conjugation of cell-penetrating peptides (CPPs) increases the cellular uptake and water solubility of agents. Among the various CPPs, arginine-rich peptides have been the most widely used. Combining CPPs with enzyme-responsive peptides presents an innovative strategy to target specific intracellular enzymes in cancer cells and when combined with the appropriate click chemistry can enhance theranostic drug delivery through the formation of intracellular self-assembled nanostructures. However, one drawback of CPPs is their high positive charge which can cause nonspecific binding, leading to off-target accumulation and potential toxicity. Hence, balancing cell-specific penetration, toxicity, and biocompatibility is essential for future clinical efficacy. We synthesized six cancer-specific, legumain-responsive RnAANCK peptides containing one to six arginine residues, with legumain being an asparaginyl endopeptidase that is overexpressed in aggressive prostate tumors. When conjugated to Alexa Fluor 488, R1-R6AANCK peptides exhibited a concentration- and time-dependent cell penetration in prostate cancer cells, which was higher for peptides with higher R values, reaching a plateau after approximately 120 min. Highly aggressive DU145 prostate tumor cells, but not less aggressive LNCaP cells, self-assembled nanoparticles in the cytosol after the cleavage of the legumain-specific peptide. The in vivo biocompatibility was assessed in mice after the intravenous injection of R1-R6AANCK peptides, with concentrations ranging from 0.0125 to 0.4 mmol/kg. The higher arginine content in R4-6 peptides showed blood and urine indicators for the impairment of bone marrow, liver, and kidney function in a dose-dependent manner, with instant hemolysis and morbidity in extreme cases. These findings underscore the importance of designing peptides with the optimal arginine residue length for a proper balance of cell-specific penetration, toxicity, and in vivo biocompatibility.

Deciphering relationship between depression and microbial molecules based on multi-omics: A case study of Chaigui Granules

ObjectiveTo decipher the antidepression effect of Chaigui Granules (CGKL) from the relationship between depression and microbial molecules based on multi-omics. MethodsMale SD rats were subjected to chronic unpredictable mild stress (CUMS) for seven weeks. The antidepressants CGKL extract and CGKL were administered for the following four weeks. The behavior test and the content of monoamine neurotransmitters were used to evaluate the efficacy of CGKL. The 16S rRNA sequencing, LC-MS technology and molecular biological techniques were used to explore the pharmacological mechanism of CGKL. ResultsCGKL treatment obviously alleviated the depressive behavioral indicators and regulated the content of monoamine neurotransmitters, and presented dose-dependent manner. CGKL could also improve the arginine metabolism disorder of gut microbiota in the jejunum. Meanwhile, the contents of arginine and its metabolites in the serum and hippocampus were regulated to normal levels. Further investigation indicated that the expression of related rate-limiting enzyme genes and proteins in the hippocampus was validated by qRT-PCR and Western blotting. The results showed that the gut microbiota, metabolites, and genes or proteins of rate-limiting enzymes involved in the arginine pathway were significantly regulated by CGKL. ConclusionThe present study demonstrates that CGKL might exert antidepressant effects through regulating arginine metabolism, and its mechanism may be related to modulating the gut microbiota and related metabolic enzyme.

Effect of Goji Berry extract on cell viability of Lactiplantibacillus plantarum M5 microcapsules during in vitro gastrointestinal digestion.

Lactiplantibacillus plantarum M5 and Goji Berry extract were co-microencapsulated to maintain the activity of cells during gastrointestinal digestion, and the mechanism by which they could maintain high activity was investigated. The results showed that the microcapsules with 3% Goji Berry extract(A-GE-3) had the largest encapsulation efficiency(EE) of 92.41 ± 0.58%. SEM showed that the structure of A-GE-3 microcapsules were smoother and denser. Cell viability in A-GE-3 microcapsules remained at 7.17 log10 CFU/g after gastrointestinal digestion. Meanwhile, during the gastrointestinal digestion with 3% Goji Berry extract, cell membrane damage detected by fluorescent probes propidium iodide(PI) and 1.1-N-phenylnaphthylamine(NPN) was significantly reduced; the contents of arginine, glutamic acid and oleic acid in cell membrane were increased, which helped to maintain the dynamic balance of intracellular pH and regulated cell membrane fluidity in response to gastrointestinal environment. This study demonstrated the potential of Goji Berry extract as a probiotic protector in gastrointestinal digestion.

Methyl jasmonate differentially and tissue-specifically regulated the expression of arginine catabolism–related genes and proteins in Agaricus bisporus mushrooms during storage

Methyl jasmonate (MeJA)-regulated postharvest quality retention of Agaricus bisporus fruiting bodies is associated with arginine catabolism. However, the mechanism of MeJA-regulated arginine catabolism in edible mushrooms is still unclear. This study aimed to investigate the regulatory modes of MeJA on the expression of arginine catabolism–related genes and proteins in intact and different tissues of A. bisporus mushrooms during storage. Results showed that exogenous MeJA treatment activated endogenous JA biosynthesis in A. bisporus mushrooms, and differentially and tissue-specifically regulated the expression of arginine catabolism–related genes (AbARG, AbODC, AbSPE-SDH, AbSPDS, AbSAMDC, and AbASL) and proteins (AbARG, AbSPE-SDH, AbASL, and AbASS). MeJA caused no significant change in AbASS expression but resulted in a dramatic increase in AbASS protein level. Neither the expression of the AbSAMS gene nor the AbSAMS protein was conspicuously altered upon MeJA treatment. Additionally, MeJA reduced the contents of arginine and ornithine and induced the accumulation of free putrescine and spermidine, which was closely correlated with MeJA-regulated arginine catabolism–related genes and proteins. Hence, the results suggested that the differential and tissue-specific regulation of arginine catabolism–related genes and proteins by MeJA contributed to their selective involvement in the postharvest continuing development and quality retention of button mushrooms.