Pathological mechanisms of type 1 diabetes in children: investigation of the exosomal protein expression profile

IntroductionType 1 diabetes (T1D) is a serious autoimmune disease with high morbidity and mortality. Early diagnosis and treatment remain unsatisfactory. While the potential for development of T1D biomarkers in circulating exosomes has attracted interest, progress has been limited. This study endeavors to explore the molecular dynamics of plasma exosome proteins in pediatric T1D patients and potential mechanisms correlated with T1D progressionMethodsLiquid chromatography-tandem mass spectrometry with tandem mass tag (TMT)6 labeling was used to quantify exosomal protein expression profiles in 12 healthy controls and 24 T1D patients stratified by age (≤ 6 years old and > 6 years old) and glycated hemoglobin (HbA1c) levels (> 7% or > 7%). Integrated bioinformatics analysis was employed to decipher the functions of differentially expressed proteins, and Western blotting was used for validation of selected proteins' expression levels. ResultsWe identified 1035 differentially expressed proteins (fold change > 1.3) between the T1D patients and healthy controls: 558 in those ≤ 6-year-old and 588 in those > 6-year-old. In those who reached an HbA1c level < 7% following 3 or more months of insulin therapy, the expression levels of most altered proteins in both T1D age groups returned to levels comparable to those in the healthy control group. Bioinformatics analysis revealed that differentially expressed exosome proteins are primarily related to immune function, hemostasis, cellular stress responses, and matrix organization. Western blotting confirmed the alterations in RAB40A, SEMA6D, COL6A5, and TTR proteins. DiscussionThis study delivers valuable insights into the fundamental molecular mechanisms contributing to T1D pathology. Moreover, it proposes potential therapeutic targets for improved T1D management

Semi-rational engineering an aldo–keto reductase for stereocomplementary reduction of α-keto amide compounds

Abstract Enantio-pure α-hydroxy amides are valuable intermediates for the synthesis of chiral pharmaceuticals. The asymmetric reduction of α-keto amides to generate chiral α-hydroxy amides is a difficult and challenging task in biocatalysis. In this study, iolS, an aldo–keto reductase from Bacillus subtilis 168 was exhibited as a potential biocatalyst, which could catalyze the reduction of diaryl α-keto amide such as 2-oxo-N, 2-diphenyl-acetamide (ONDPA) with moderate S-selectivity (76.1%, ee) and 60.5% conversion. Through semi-rational engineering, two stereocomplementary variants (I57F/F126L and N21A/F126A) were obtained with ee value of 97.6% (S) and 99.9% (R) toward ONDPA (1a), respectively, delivering chiral α-hydroxy amide with > 98% conversions. Moreover, the excellent S- and R-preference variants displayed improved stereoselectivities toward the other α-keto amide compounds. Molecular dynamic and docking analysis revealed that the two key residues at 21 and 126 were identified as the “switch”, which specifically controlled the stereopreference of iolS by regulating the shape of substrate binding pocket as well as the substrate orientation. Our results offer an effective strategy to obtain α-hydroxy amides with high optical purity and provide structural insights into altering the stereoselectivity of AKRs. Graphical Abstrac

Reminiscence and Introspection: Influence of Tourism Memory Construction on Expansion of Individual Self-Concept

Memory is an essential structure of the tourism experience. Tourism memory construction is not only an individual's review and sublimation of on-site experience, but also the pursuit and introspection of self-meaning. Although tourism memory is unique and critical, it has not yet been fully examined in local tourism studies, resulting in the focus on on-site experience while ignoring the special role of tourism memory in shaping the landscape and constructing individual self-cognition. In this study, based on theories of autobiographical memory and self-expansion, the Grounded Theory and Structural Equation Model were adopted to investigate the influence mechanism of tourism memory construction on tourists' self-concept expansion based on excavating the dimensions of tourism memory construction. The results showed that: 1) Tourism memory is an unforgettable autobiographical memory formed by individual screening and construction after tourists' on-site experience. Its construction dimensions comprise three basic structures: cognitive appraisal, interactive perception, and affective involvement. Specifically, cognitive appraisal refers to the cognitive feelings generated by tourists based on the objective environment of destinations in their memory. Interactive perception is the participatory perception of the interaction between the host and guest and the interaction between tourists. Affective involvement reflects the emotional properties of memory, which is the corresponding emotional reaction of tourists based on cognitive appraisal and interactive perception. These three elements are interrelated and jointly shape and interpret the landscape constructing tourist' self-identity. 2) Cognitive appraisal, interactive perception, and positive affective involvement in tourism memory help promote tourism-sharing behavior, which significantly and positively influences the individual and social self-expansion of tourists. This finding confirms that cognitive and interactive memories contribute to tourism-sharing behavior. In particular, positive and negative affective involvements are remembered by tourists, but many tourists are more willing to share "positive energy" and express the positive side of tourism memories. In addition, through self-narration and self-expression, tourism sharing deepens reflection of the overall self-perception. 3) Among the direct effects of tourism memory construction on self-concept expansion, cognitive appraisal and interactive perception significantly and positively affect individual and social self-expansion, whereas positive affective involvement only positively affects individual self-expansion and indirectly affects social self-expansion by tourism sharing. Furthermore, this paper theoretically clarifies the dimensions of tourism memory construction, complements the theoretical deficiencies of post-travel memory in previous tourism experience studies, and reveals the subjective significance of tourism memory to self. This paper also introduces the concept of self-expansion in tourism research and complements self-expansion studies in nonrelational contexts. Finally, this study is a practical reference for memory marketing in destinations

Spatial distribution and tourism competition of intangible cultural heritage: take Guizhou, China as an example

Abstract As a province inhabited by ethnic minorities in southwest China, Guizhou is rich in tourism and ICH (intangible cultural heritage) resources. The spatial distribution of ICH and the utilization of tourism and ICH resources in Guizhou worth studying, which is better for understanding the tourism competition situation and the tourism utilization of ICH. This research uses GIS tools for spatial analysis, mathematical formulas for calculating the abundance of ICH and tourism resources, as well as the matrix analysis for ICH and tourism competition, to identify the spatial distribution and tourism competition situation of ICH in Guizhou Province in 2019. The results show that: (1) in terms of the structural characteristics of the number and types of ICH in Guizhou Province, folk custom, traditional craftsmanship and traditional music have the highest number and proportion, while Quyi has the lowest. (2) Grade A scenic spots are mainly located in Zunyi City, while ICH scenic spots are mainly in Southeast Guizhou, Zunyi City, South Guizhou and Southwest Guizhou. Zunyi City ranks first in the abundance of tourism resources, and Liupanshui City ranks last. Southeast Guizhou has the highest ICH resources abundance, while Liupanshui City has the lowest. (3) Both the distribution of national-level and provincial-level ICH in Guizhou are aggregated. The national-level ICH are clustered in a large core area in geographical space, which is located in the southeast of Guizhou. The provincial-level ICH sites form a belt extending from southwest to southeast of the province, which is distributed at the junction of southeast of Guizhou, Guiyang and Anshun. (4) The provincial-level ICH in Guizhou has formed a belt-like high-density zone extending from southwest to southeast and three high-density core areas. (5) Through the analysis of a tourism competition matrix, we found that there are three types of development in nine cities in Guizhou Province. Zunyi City and Southeast Guizhou show the development characteristics of “tourism prosperity-ICH tourism prosperity”. Guiyang, Bijie, Anshun, Southwest Guizhou, Liupanshui and Tongren City show the development characteristics of “tourism depression-ICH tourism depression”. South Guizhou shows “tourism depression-ICH tourism prosperity”. These findings and methods will help cities determine their own strengths and weaknesses according to their resources, and narrow the regional development gap through formulating cultural and tourism development plans

Identification of histone acetylation markers in human fetal brains and increased H4K5ac expression in neural tube defects

Abstract Background Neural tube defects (NTDs) are severe common birth defects that result from a failure in neural tube closure (NTC). Our previous study has shown that decreased histone methylation altered the regulation of genes linked to NTC. However, the effect of alterations in histone acetylation in human fetuses with NTDs, which are another functional posttranslation modification, remains elusive. Thus, we aimed to identify acetylation sites and changes in histone in patients with NTDs. Methods First, we identified histone acetylation sites between control human embryonic brain tissue and NTDs using Nano‐HPLC‐MS/MS. Next, we evaluated the level of histone acetylation both groups via western blotting (WB). Finally, we used LC‐ESI‐MS and WB to compare whether histone H4 acetylation was different in NTDs. Results A total of 43 histone acetylation sites were identified in human embryonic brain tissue, which included 16 novel sites. Furthermore, we found an increased histone acetylation and H4K5ac in tissue with NTDs. Conclusion Our result present a comprehensive map of histone H4 modifications in the human fetal brain. Furthermore, we provide experimental evidence supporting a relationship between histone H4K5ac and NTDs. This offers a new insight into the pathological role of histone modifications in human NTDs

Mutations in the Motile Cilia Gene DNAAF1 Are Associated with Neural Tube Defects in Humans

Neural tube defects (NTDs) are severe malformations of the central nervous system caused by complex genetic and environmental factors. Among genes involved in NTD, cilia-related genes have been well defined and found to be essential for the completion of neural tube closure (NTC). We have carried out next-generation sequencing on target genes in 373 NTDs and 222 healthy controls, and discovered eight disease-specific rare mutations in cilia-related gene DNAAF1. DNAAF1 plays a central role in cytoplasmic preassembly of distinct dynein-arm complexes, and is expressed in some key tissues involved in neural system development, such as neural tube, floor plate, embryonic node, and brain ependyma epithelial cells in zebrafish and mouse. Therefore, we evaluated the expression and functions of mutations in DNAAF1 in transfected cells to analyze the potential correlation of these mutants to NTDs in humans. One rare frameshift mutation (p.Gln341Argfs*10) resulted in significantly diminished DNAAF1 protein expression, compared to the wild type. Another mutation, p.Lys231Gln, disrupted cytoplasmic preassembly of the dynein-arm complexes in cellular assay. Furthermore, results from NanoString assay on mRNA from NTD samples indicated that DNAAF1 mutants altered the expression level of NTC-related genes. Altogether, these findings suggest that the rare mutations in DNAAF1 may contribute to the susceptibility for NTDs in humans

Identification of histone malonylation in the human fetal brain and implications for diabetes‐induced neural tube defects

Abstract Background Neural tube defects (NTDs) are severe congenital malformations. Diabetes during pregnancy is a risk factor for NTDs, but its mechanism remains elusive. Emerging evidence suggests that protein malonylation is involved in diabetes. Here, we report the correlation between histone lysine malonylation in diabetes‐induced NTDs. Methods Nano‐HPLC/MS/MS was used to screen the histone malonylation profile in human embryonic brain tissue. Then, the histone malonylation level was compared between the brains of normal control mice and mice with diabetes‐induced NTDs. Finally, the histone malonylation level was compared under high glucose exposure in an E9 neuroepithelial cell line (NE4C). Results A total of 30 histone malonylation sites were identified in human embryonic brain tissue, including 18 novel sites. Furthermore, we found an increased histone malonylation level in brain tissues from mice with diabetes‐induced NTDs. Finally, both the histone malonylation modified sites and the modified levels were proved to be increased in the NE4C treated with high glucose. Conclusion Our results present a comprehensive map of histone malonylation in the human fetal brain. Furthermore, we provide experimental evidence supporting a relationship between histone malonylation and NTDs caused by high glucose‐induced diabetes. These findings offer new insights into the pathological role of histone modifications in human NTDs

Table_1_Pathological mechanisms of type 1 diabetes in children: investigation of the exosomal protein expression profile.xlsx

IntroductionType 1 diabetes (T1D) is a serious autoimmune disease with high morbidity and mortality. Early diagnosis and treatment remain unsatisfactory. While the potential for development of T1D biomarkers in circulating exosomes has attracted interest, progress has been limited. This study endeavors to explore the molecular dynamics of plasma exosome proteins in pediatric T1D patients and potential mechanisms correlated with T1D progressionMethodsLiquid chromatography-tandem mass spectrometry with tandem mass tag (TMT)6 labeling was used to quantify exosomal protein expression profiles in 12 healthy controls and 24 T1D patients stratified by age (≤ 6 years old and > 6 years old) and glycated hemoglobin (HbA1c) levels (> 7% or > 7%). Integrated bioinformatics analysis was employed to decipher the functions of differentially expressed proteins, and Western blotting was used for validation of selected proteins' expression levels. ResultsWe identified 1035 differentially expressed proteins (fold change > 1.3) between the T1D patients and healthy controls: 558 in those ≤ 6-year-old and 588 in those > 6-year-old. In those who reached an HbA1c level DiscussionThis study delivers valuable insights into the fundamental molecular mechanisms contributing to T1D pathology. Moreover, it proposes potential therapeutic targets for improved T1D management.</p

Image_2_Pathological mechanisms of type 1 diabetes in children: investigation of the exosomal protein expression profile.jpeg

IntroductionType 1 diabetes (T1D) is a serious autoimmune disease with high morbidity and mortality. Early diagnosis and treatment remain unsatisfactory. While the potential for development of T1D biomarkers in circulating exosomes has attracted interest, progress has been limited. This study endeavors to explore the molecular dynamics of plasma exosome proteins in pediatric T1D patients and potential mechanisms correlated with T1D progressionMethodsLiquid chromatography-tandem mass spectrometry with tandem mass tag (TMT)6 labeling was used to quantify exosomal protein expression profiles in 12 healthy controls and 24 T1D patients stratified by age (≤ 6 years old and > 6 years old) and glycated hemoglobin (HbA1c) levels (> 7% or > 7%). Integrated bioinformatics analysis was employed to decipher the functions of differentially expressed proteins, and Western blotting was used for validation of selected proteins' expression levels. ResultsWe identified 1035 differentially expressed proteins (fold change > 1.3) between the T1D patients and healthy controls: 558 in those ≤ 6-year-old and 588 in those > 6-year-old. In those who reached an HbA1c level DiscussionThis study delivers valuable insights into the fundamental molecular mechanisms contributing to T1D pathology. Moreover, it proposes potential therapeutic targets for improved T1D management.</p

Image_3_Pathological mechanisms of type 1 diabetes in children: investigation of the exosomal protein expression profile.jpeg

IntroductionType 1 diabetes (T1D) is a serious autoimmune disease with high morbidity and mortality. Early diagnosis and treatment remain unsatisfactory. While the potential for development of T1D biomarkers in circulating exosomes has attracted interest, progress has been limited. This study endeavors to explore the molecular dynamics of plasma exosome proteins in pediatric T1D patients and potential mechanisms correlated with T1D progressionMethodsLiquid chromatography-tandem mass spectrometry with tandem mass tag (TMT)6 labeling was used to quantify exosomal protein expression profiles in 12 healthy controls and 24 T1D patients stratified by age (≤ 6 years old and > 6 years old) and glycated hemoglobin (HbA1c) levels (> 7% or > 7%). Integrated bioinformatics analysis was employed to decipher the functions of differentially expressed proteins, and Western blotting was used for validation of selected proteins' expression levels. ResultsWe identified 1035 differentially expressed proteins (fold change > 1.3) between the T1D patients and healthy controls: 558 in those ≤ 6-year-old and 588 in those > 6-year-old. In those who reached an HbA1c level DiscussionThis study delivers valuable insights into the fundamental molecular mechanisms contributing to T1D pathology. Moreover, it proposes potential therapeutic targets for improved T1D management.</p