Wybutosine hypomodification of tRNAphe activates HERVK and impairs neuronal differentiation.

We previously reported that loss of function of TYW1 led to cerebral palsy with severe intellectual disability through reduced neural proliferation. However, whether TYW1 loss affects neural differentiation is unknown. In this study, we first demonstrated that TYW1 loss blocked the formation of OHyW in tRNAphe and therefore affected the translation efficiency of UUU codon. Using the brain organoid model, we showed impaired neuron differentiation when TYW1 was depleted. Interestingly, retrotransposons were differentially regulated in TYW1-/- hESCs (human embryonic stem cells). In particular, one kind of human-specific endogenous retrovirus-K (HERVK/HML2), whose reactivation impaired human neurodevelopment, was significantly up-regulated in TYW1-/- hESCs. Consistently, a UUU codon-enriched protein, SMARCAD1, which was a key factor in controlling endogenous retroviruses, was reduced. Taken together, TYW1 loss leads to up-regulation of HERVK in hESCs by down-regulated SMARCAD1, thus impairing neuron differentiation.

Association of Physical Activity with Phenotypic Age among Populations with Different Breakfast Habits.

BACKGROUND: The global aging situation has reached a serious stage, and healthy lifestyles, like regular physical activity and eating breakfast, could slow the process. Phenotypic age (PhenoAge) is regarded as a novel measure of aging. Therefore, our study aimed to quantify the impact of physical activity and eating breakfast on aging via PhenoAge and phenotypic age acceleration (PhenoAgeAccel). METHODS: A total of 3719 adults who participated in the National Health and Nutrition Examination Survey were involved in this study. Physical activity was divided into an active group and an inactive group. According to the number of reported breakfast recalls, eating breakfast was divided into the no recalls group, one recall group, and both recalls group. Sensitivity analysis was performed by stratified analysis. RESULTS: Active physical activity was a protective factor for PhenoAge and PhenoAgeAccel. Compared to the inactive group, the ß values of the active group were -8.36 (-10.09, -6.62) for PhenoAge and -1.67 (-2.21, -1.14) for PhenoAgeAccel. The stratified analysis results showed that in the groups reporting breakfast in both recalls, one recall, and no recalls, the ß values of the active group were -8.84 (-10.70, -6.98), -8.17 (-12.34, -4.00), and -3.46 (-7.74, 0.82), respectively, compared to the inactive group. CONCLUSIONS: Active physical activity was strongly correlated with lower values of PhenoAge and PhenoAgeAccel, but the association was no longer statistically significant when combined with not regularly eating breakfast.

The association between vitamin K intake and dyslipidemia in US adults: the mediating effect of insulin resistance.

Background: Dyslipidemia is one of the most common chronic diseases, and is associated with insulin resistance (IR) and inadequate vitamin K intake. We aimed to explore the association between IR, vitamin K intake, and dyslipidemia, and further to explore the mediating role of IR. Materials and methods: 12 860 participants from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2018 were included in this study. Insulin resistance was determined by using the homeostatic model assessment for insulin resistance (HOMA-IR). Weighted multiple logistic regression and mediation analyses were conducted to analyze the associations between IR, vitamin K intake, and dyslipidemia. Results: We found that both vitamin K intake-met Dietary Reference Intake (DRI) and non-IR were protective factors of high triglycerides (with ORs (95% CI) of 0.71 (0.57, 0.87) and 0.36 (0.29, 0.45), respectively) and low high-density lipoprotein cholesterol (with ORs (95% CI) of 0.72 (0.62, 0.82) and 0.39 (0.34, 0.41), respectively). IR-related indicators (HOMA-IR and insulin) partly mediated these effects, and the proportion ranged from 16.36% to 18.52%. Conclusion: Vitamin K intake-met DRI and non-IR were associated with lower risk of dyslipidemia including high TG and low HDL-C. IR partly mediated the association of vitamin K intake with high TG and low HDL-C.

Ideal cardiovascular health metrics have better identification of arthritis.

BACKGROUND: This study aimed to explore the association between ideal cardiovascular health metrics (ICVHM) and arthritis (AR), as well as the interactions of various indicators in ICVHM on AR in US adults. METHODS: We involved 17,041 participants who were interviewed by NHANES from 2011 to 2018. AR included osteoarthritis or degenerative arthritis (OA), rheumatoid arthritis (RA), and psoriatic arthritis and other arthritis (Other AR). Logistic regression was applied to analyze the association between AR and ICVHM. Mixed graphical model (MGM) was used to explore the interaction between variables in ICVHM. RESULTS: Higher ICVHM scores had a protective effect on AR. Compared to "≤1" score, the ORs of AR in participants with 2, 3, 4, and ≥5 were 0.586, 0.472, 0.259, and 0.130, respectively. Similar results were also found in different types of AR. ICVHM has a maximum area under the curve value of 0.765 and the interaction between blood pressure and total cholesterol was 0.43. CONCLUSIONS: ICVHM correlates significantly with AR and is better at identifying AR than individual indicators. ICVHM can be better improved by controlling the indicators with stronger interactions. Our findings provide guidance for promoting health factors, which have important implications for identification and prevention of AR.

The mediating role of dietary inflammatory index on the association between eating breakfast and depression: Based on NHANES 2007-2018.

BACKGROUND: Depression is a significant, pervasive, global public health problem, associated with many factors, such as diet, social factors, and lifestyle habits. We aimed to evaluate the association between eating breakfast, dietary inflammatory index (DII) and depression, and to verify the mediating role of DII on the effect of eating breakfast on depression. METHODS: 21,865 participants from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018 were included in this study. Binary logistic regression and mediated effect analysis were conducted to analyze the associations between eating breakfast, DII and depression. Dietary inflammation was divided into pro-inflammatory diet and anti-inflammatory diet according to the DII. RESULTS: Both pro-inflammatory diet and skipping breakfast were risk factors for depression. After adjusting for covariables, compared with participants reporting breakfast in both recalls, reporting breakfast in one recall had a higher OR 95%CI (1.54(1.20, 1.98)) of depression. These associations in stratified analysis and sensitivity analysis without cardiovascular diseases (CVD) and diabetes were robust. DII mediated the association between eating breakfast and depression, the proportion of participants who reported breakfast in one recall and no recall was 26.15 % and 26.67 %, respectively. LIMITATIONS: This was a cross-sectional study that couldn't argue for the cause-effect relationship. Moreover, the confounding factor regarding medication use was not accounted for due to limited data. CONCLUSIONS: Skipping breakfast may increase the risk of depression by raising DII. And our study supported the essential role of regular breakfast and the anti-inflammatory diet in reducing the risk of depression.

Cascade catalysis-coordinated nanorobots toward synergistic cancer chemoimmunotherapy.

Cancer has always been the biggest threat to human health, but the effect of traditional treatments such as surgery, chemotherapy, and radiotherapy is not satisfactory. Currently, nanomedicine-based chemoimmunotherapy can improve clinical results through unique synergistic effects. However, it is mainly enriched at tumor sites based on EPR effects, without an active delivery strategy and relatively low tumor targeting distribution. Therefore, nanorobots (Cu@MPS-GOD) with magnetic responsiveness and enzyme-like activity were prepared, which can enrich and move to the tumor site under the action of a 3D magnetic field, and cause tumor cell immunogenic death by cascade catalytic Fenton reactions. Meanwhile, Cu@MPS-GOD can also activate immune cells or induce cancer cells to expose surface antigens, trigger systemic anti-cancer immunity, and have a good inhibitory effect on a breast tumor model in mice with an inhibition rate of 59.3%. This work provides an attractive strategy to expand the therapeutic effect of cancer when chemical dynamic therapy is combined with immunotherapy, which has a potential clinical application prospect.

PARP12 regulates mouse oocyte meiotic maturation.

Poly(ADP-ribosyl)ation (PARylation) is an important post-translational modification of proteins that involves the transfer of ADP-ribose moieties, and plays important roles in many biological processes including DNA repair, gene expression, RNA processing, ribosome biogenesis, and protein translation. Though it is accepted that PARylation is crucial for oocyte maturation, little is known about how Mono(ADP-ribosyl)ation (MARylation) regulates this process. Here, we report that Parp12, a mon(ADP-ribosyl) transferase of poly(ADP-ribosyl) polymerase (PARP) family, was highly expressed at all stages of oocytes during meiotic maturation. At germinal vesicle (GV) stage, PARP12 was mainly distributed in cytoplasm. Interestingly, PARP12 formed granular aggregation near to spindle poles during metaphase I (MI) and metaphase II (MII). PARP12 depletion results in abnormal spindle organization and chromosome misalignment in mouse oocytes. Chromosome aneuploidy frequency in PARP12 knockdown oocytes was significantly increased. Importantly, PARP12 knockdown triggers activation of spindle assembly checkpoint as shown by active BUBR1 in PARP12-KD MI oocytes. Besides, F actin was significantly attenuated in PARP12-KD MI oocytes which may affect the asymmetric division process. Transcriptomic analysis demonstrated that PARP12 depletion disrupts transcriptome homeostasis. Collectively, our results showed that the maternally expressed mono(ADPribosyl) transferases PARP12 was essential for oocyte meiotic maturation in mouse.

The role of dietary inflammatory index and physical activity in depressive symptoms: Results from NHANES 2007-2016.

BACKGROUND: Depression is a major public health problem. This study was aimed to analyze the relationship between Dietary Inflammatory Index (DII), physical activity, and depressive symptoms, and to explore the effect of different lifestyles on depressive symptoms by combining DII and physical activity to form four lifestyle groups. METHODS: This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2016. A total of 21,785 subjects were involved. Depressive symptoms and dietary inflammation were measured by the Patient Health Questionnaire (PHQ-9) and Energy-adjusted Dietary Inflammatory Index, respectively. The participants were divided subgroups by different physical activity combined pro-inflammatory or anti-inflammatory diet groups. RESULTS: Both pro-inflammatory diet and inactivity were positively associated with depressive symptoms. Compared with the anti-inflammatory diet & active group, the risk of depressive symptoms was 2.061 times higher in the pro-inflammatory diet & inactive group, 1.351 times higher in the pro-inflammatory diet & active group, and 1.603 times higher in the anti-inflammatory diet & inactive group. Physical inactivity was associated with a higher risk of depressive symptoms than a pro-inflammatory diet. Females and the 20-39 age group showed a strong association between lifestyles and depressive symptoms. LIMITATIONS: Because of the cross-sectional study, no causal conclusions could be drawn. Moreover, PHQ-9 is a relatively basic method of identifying depressive symptoms, more and further research is needed. CONCLUSIONS: Both a pro-inflammatory diet and physical inactivity were associated with higher risk of depressive symptoms, especially for young and female population.

Intelligent Jellyfish-type Janus Nanoreactor Targeting Synergistic Treatment of Bacterial Infections.

Infections caused by multidrug-resistant bacteria continue to pose a serious threat to human health, and therefore it is important to explore the availability of antimicrobial drugs and modalities. Herein, jellyfish-type irregular mesoporous iron oxide nanoreactors containing ciprofloxacin, Janus Fe3O4@mSiO2@Cip nanoparticles (JFmS@Cip NPs), were developed for pH-responsive synergistic antimicrobial therapy in a microacidic environment. Compared with the use of symmetric nanocarriers, the asymmetric decoration on both sides of the particles allows different components to act on bacteria, Fe3O4 NPs have good magnetic and peroxidase-like catalytic activity, and the antibiotic ciprofloxacin can kill bacteria efficiently. Notably, due to the synergistic effect between different components of Janus particles, in vitro antibacterial experiments showed that JFmS@Cip NPs can kill bacteria efficiently at low concentrations, reaching an antibacterial rate of 99.6%. JFmS@Cip NPs combine multiple antibacterial properties that can be used to improve the therapeutic efficacy of current nanomedicines against drug-resistant bacteria.

Immune-enhancing activity of polysaccharides and flavonoids derived from Phellinus igniarius YASH1.

Introduction: Phellinus igniarius (P. igniarius) (Sanghuang) is a widely used traditional Chinese medicine fungus, and its natural products have great potential for clinical application in immune enhancement. This study aimed to explore the immune-enhancing activity and underlying mechanisms of the polysaccharides and flavonoids derived from Phellinus igniarius (P. igniarius) and to provide a theoretical and experimental basis for the development of novel drugs. Methods: Wild P. igniarius YASH1 from the Loess Plateau in Yan'an region was collected, and polysaccharides and total flavonoids were extracted, isolated and identified from mycelium and sporophore. In vitro antioxidant activity was detected through the scavenging activity of hydroxyl radicals and total antioxidant capacity. Cell Counting Kit-8 and trypan blue detection kit were used to detect the effect of extract polysaccharides and flavonoids on the proliferation and phagocytosis ability of immune cells. To assess the effect of the drugs on cytokine secretion by immune cells and immune recovery in immunocompromised mice, the expression of interleukin (IL)-2, IL-6, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α were examined at the cellular and animal levels. The species composition, abundance of gut microbiota and the altered content of short-chain fatty acids in the feces were analyzed to elucidate the possible mechanisms of drugs by 16S ribosomal RNA (rRNA) amplifiers sequencing and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Both polysaccharides and flavonoids derived from mycelium or sporophore had antioxidant activity and may stimulate the expression and secretion of IL-2, IL-6, and IFN-γ in immune cells while inhibiting TNF-α expression and secretion and increasing IL-2, IL-6, and IFN- γ expression levels in mice. Furthermore, polysaccharides and flavonoids from mycelium and sporophore showed different effects on the metabolic response of intestinal short-chain fatty acids (SCFAs) in mice, and the use of these drugs remarkably changed the species composition and abundance of intestinal flora in mice. Discussion: Polysaccharides and flavonoids from P. igniarius YASH1 mycelium and sporophore have in vitro antioxidant activity, and they affect the promotion of cell proliferation, stimulation of IL-2, IL-6, and IFN-γ secretion, and inhibition of TNF-α expression in immune cells. Polysaccharides and flavonoids from P. igniarius YASH1 may enhance immunity in immunocompromised mice and remarkably affect the intestinal flora and content of SCFAs.

Vision impairment, hearing impairment and functional Limitations of subjective cognitive decline: a population-based study.

BACKGROUND: The association between sensory impairment including vision impairment (VI), hearing impairment (HI), dual impairment (DI) and the functional limitations of SCD (SCD-related FL) are still unclear in middle-aged and older people. METHODS: 162,083 participants from BRFSS in 2019 to 2020 was used in this cross-sectional study. After adjusting the weights, multiple logistic regression was used to study the relationship between sensory impairment and SCD or SCD-related FL. In addition, we performed subgroup analysis on the basis of interaction between sensory impairment and covariates. RESULTS: Participants who reported sensory impairment were more likely to report SCD or SCD-related FL compared to those without sensory impairment (p < 0.001). The association between dual impairment and SCD-related FL was the strongest, the adjusted odds ratios (aORs) and 95% confidence interval (95% CI) were [HI, 2.88 (2.41, 3.43); VI, 3.15(2.61, 3.81); DI, 6.78(5.43, 8.47)] respectively. In addition, subgroup analysis showed that men with sensory impairment were more likely to report SCD-related FL than women, the aORs and 95% CI were [HI, 3.15(2.48, 3.99) vs2.69(2.09, 3.46); VI,3.67(2.79, 4.83) vs. 2.86(2.22, 3.70); DI, 9.07(6.67, 12.35) vs. 5.03(3.72, 6.81)] respectively. The subject of married with dual impairment had a stronger association with SCD-related FL than unmarried subjects the aOR and 95% CI was [9.58(6.69, 13.71) vs. 5.33(4.14, 6.87)]. CONCLUSIONS: Sensory impairment was strongly associated with SCD and SCD-related FL. Individuals with dual impairment had the greatest possibility to reported SCD-related FL, and the association was stronger for men or married subjects than other subjects.

Mediation of 10-Year Cardiovascular Disease Risk between Inflammatory Diet and Handgrip Strength: Base on NHANES 2011-2014.

OBJECTIVE: Dietary inflammatory index (DII) and handgrip strength (HGS) were correlated, and both were associated with cardiovascular disease (CVD). However, the role of the 10-year CVD risk in the relationship between DII and grip strength remains uncertain. METHODS: This study involved 5691 adults from the National Health and Nutrition Examination Survey (NHANES) in 2011-2014. Dietary inflammation, 10-year CVD risk and relative grip strength were assessed by the Dietary Inflammation Index, the Framingham Risk Score (FRS) and handgrip strength adjusted BMI. Linear regression analyses and mediation analysis were used to explore these associations. RESULTS: Both DII and 10-year CVD risk were negatively associated with relative handgrip strength, and DII was positively associated with 10-year CVD risk. Additionally, 10-year CVD risk partially mediated the association between DII and relative handgrip strength by a 11.8% proportion. Specifically, the mediating effect of the 10-year risk of CVD varied by gender and age. CONCLUSIONS: Reducing the 10-year risk of CVD attenuates the effect of an inflammatory diet on relative grip strength impairment. Therefore, we recommend reducing the effect of inflammatory diet on grip strength impairment by controlling any of the FRS parameters, such as lowering blood pressure and smoking cessation, especially with targeted measures for different populations.

Perturbation of intestinal stem cell homeostasis and radiation enteritis recovery via dietary titanium dioxide nanoparticles.

Small intestinal health and enteritis incidence are tightly coupled to the homeostasis of intestinal stem cells (ISCs), which are sensitive to dietary alterations. However, little is known about the impact of food additives on ISC pool. Here, we demonstrate that chronic exposure to low-dose TiO2 NPs, a commonly used food additive, significantly hampers primary human and mouse ISC-derived organoid formation and growth by specifically attenuating Wnt signal transduction. Mechanistically, TiO2 NPs alter the endocytic trafficking of the Wnt receptor LRP6 and prevent the nuclear entry of ß-catenin. Notably, dietary TiO2 NPs elicit modest chronic stress in healthy intestines and considerably impede the recovery of radiation enteritis by perturbing the homeostasis of ISCs in vivo. Our results identify a health concern of TiO2 NP exposure on ISC homeostasis and radiation enteritis recovery. These findings suggest extra precaution during the treatment of radiation enteritis and provide new insights into food additive-ISC interaction.

Analysis of Immunogenic Galactose-α-1,3-galactose-Containing N-Glycans in Beef, Mutton, and Pork Tenderloin by Combining Matrix-Assisted Laser Desorption/Ionization-Mass Spectroscopy and Capillary Electrophoresis Hyphenated with Mass Spectrometry via Electrospray Ionization.

Severe allergic reactions to certain types of meat following tick bites have been reported in geographic regions which are endemic with ticks. This immune response is directed to a carbohydrate antigen (galactose-α-1,3-galactose or α-Gal), which is present in glycoproteins of mammalian meats. At the moment, asparagine-linked complex carbohydrates (N-glycans) with α-Gal motifs in meat glycoproteins and in which cell types or tissue morphologies these α-Gal moieties are present in mammalian meats are still unclear. In this study, we analyzed α-Gal-containing N-glycans in beef, mutton, and pork tenderloin and provided for the first time the spatial distribution of these types of N-glycans in various meat samples. Terminal α-Gal-modified N-glycans were found to be highly abundant in all analyzed samples (55, 45, and 36% of N-glycome in beef, mutton, and pork, respectively). Visualizations of the N-glycans with α-Gal modification revealed that this motif was mainly present in the fibroconnective tissue. To conclude, this study contributes to a better understanding of the glycosylation biology of meat samples and provides guidance for processed meat products, in which only meat fibers are required as an ingredient (i.e., sausages or canned meat).

Generation of NANOS3-mCherry reporter human embryonic stem cell line SYSUe-009-A using CRISPR/Cas9.

NANOS3 is a zinc-finger containing RNA-binding protein that has been demonstrated to be highly expressed in human primordial germ cell(hPGC), thus NANOS3 can serve as a marker for hPGC development. Due to the ethical and technical restrictions, it is difficult to get primary human germline cells. Human primordial germ cell-like cells (hPGCLCs) generated from pluripotent stem cells is an excellent alternatives in human germ cell-related studies. This hESC line with an mCherry knock-in at the site before NANOS3's stop codon serves as a useful tool to learn human PGC specification.

Zunyimycin C enhances immunity and improves cognitive impairment and its mechanism.

This study aimed to explore the efficacy of zunyimycin C in the immunological enhancement of hypoimmune mice and improvement of cognitive impairment in a mice model of Alzheimer's disease (AD). Zunyimycin C was administered intranasally to interfere with AD mouse models or gavage to hypoimmune animals. Results of the Morris water maze (MWM) showed that zunyimycin may improve the learning and memory abilities of the AD mice model. The results of differential expression analysis of mRNA levels of inflammatory factors and pathways in brain tissues of the AD mouse model suggested that differential expression was more obvious under Zun-Int L. Western blot revealed that the relative expression of glial fibrillary acidic protein in the brain tissue of the AD mouse model in the Zun-Pre group was significantly higher than that in the other groups, and the difference was statistically significant. The relative expression of interleukin (IL)-6 protein in the brain tissue of mice in the low-dose intervention group was significantly lower than that in the other groups, and the difference was statistically significant. As for hypoimmune animals, short chain fatty acids (SCFAs) assay and intestinal flora assay results showed that zunyimycin C may change intestinal flora diversity and SCFA biosynthesis. The prophylactic administration of zunyimycin C could not inhibit acute neuroinflammation in AD mice. Zunyimycin C may participate in the immune response by activating the Ras-Raf-MEK-ERK signaling pathway to stimulate microglia to produce more inflammatory factors. Zunyimycin C may inhibit autophagy by activating the PI3K-AKT-mTOR signaling pathway, promote cell survival, mediate neuroprotective effects of reactive microglia and reactive astrocytes, and reduce IL-1ß in brain tissue and IL-6 secretion, thereby attenuating neuroinflammation in AD mice and achieving the effect of improving learning and memory impairment. Zunyimycin C may play a role in immunological enhancement by changing intestinal flora diversity and SCFAs.

The Mediating Role of Dietary Inflammatory Index in the Association between Eating Breakfast and Obesity: A Cross-Sectional Study.

Obesity is closely related with diet, including the regularity of meals and inflammation in the diet. No previous study focused on the associations among eating breakfast, which is regarded the most important meal, dietary inflammation, and obesity. This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2018, with 23,758 participants involved. Obesity and dietary inflammation were measured by body mass index (BMI) and dietary inflammatory index (DII), respectively. Eating breakfast was defined by two days of dietary recalls based on NHANES dietary data. Pro-inflammatory diet and skipping breakfast were positively associated with obesity in the whole population. Compared with eating breakfast in both recalls, skipping breakfast had the higher OR of obesity, especially for individuals who reported no recall. Participants with diabetes were the sensitive population of these associations. Compared with participants who reported breakfast in both recalls, the mediated proportion of participants reported breakfast in one recall and in no recall were 24.71% and 27.34%, respectively. The association between eating breakfast and obesity was partly mediated by DII. We recommended eating breakfast regularly to reduce dietary inflammation, as well as further obesity, especially for diabetic populations.

An Improved Method for Quick Quantification of Unsaturated Transferrin.

Blood iron levels play a vital role in oxygen metabolism and energy generation whilst transporter protein, transferrin, binds and delivers iron to the transferrin receptor of endosomal compartments of cells. Consequently, the iron-binding capacity of transferrin is an important indicator for many diseases, and its measurements are used in the diagnosis and treatment of anaemias. Various assays, including Total Iron Binding Capacity (TIBC), Unsaturated Iron-Binding Capacity (UIBC) and Transferrin Saturation (TS), were developed to assess the iron-binding capacity of transferrin. Clinically, UIBC is measured in serum by a multi-step liquid ferrozine method and subjected to interference from conditions such as haemolysis and lipemia. Here, we report a quick method that directly measures the concentration of apotransferrin in EDTA-treated plasma, theoretically equivalent to UIBC. Importantly, this supramolecular assembly-based method is more time-efficient, cost-effective and insensitive to serum cation fluctuations. With additional colorimetric property, this method also provides a visual indicator for abnormal health conditions with extreme transferrin statuses such as those found in cancers. Its minimal requirement for equipment would be particularly useful for diagnosis in remote and under-developed regions.

PNGase H + variant from Rudaea cellulosilytica with improved deglycosylation efficiency for rapid analysis of eukaryotic N-glycans and hydrogen deuterium exchange mass spectrometry analysis of glycoproteins.

The analysis of glycoproteins and the comparison of protein N-glycosylation from different eukaryotic origins require unbiased and robust analytical workflows. The structural and functional analysis of vertebrate protein N-glycosylation currently depends extensively on bacterial peptide-N4-(N-acetyl-ß-glucosaminyl) asparagine amidases (PNGases), which are indispensable enzymatic tools in releasing asparagine-linked oligosaccharides (N-glycans) from glycoproteins. So far, only limited PNGase candidates are available for N-glycans analysis, and particularly the analysis of plant and invertebrate N-glycans is hampered by the lack of suitable PNGases. Furthermore, liquid chromatography-mass spectrometry (LC-MS) workflows, such as hydrogen deuterium exchange mass spectrometry (HDX-MS), require a highly efficient enzymatic release of N-glycans at low pH values to facilitate the comprehensive structural analysis of glycoproteins. Herein, we describe a previously unstudied superacidic bacterial N-glycanase (PNGase H+ ) originating from the soil bacterium Rudaea cellulosilytica (Rc), which has significantly improved enzymatic properties compared to previously described PNGase H+ variants. Active and soluble recombinant PNGase Rc was expressed at a higher protein level (3.8-fold) and with higher specific activity (~56% increase) compared to the currently used PNGase H+ variant from Dyella japonicum (Dj). Recombinant PNGase Rc was able to deglycosylate the glycoproteins horseradish peroxidase and bovine lactoferrin significantly faster than PNGase Dj (10 min vs. 6 h). The versatility of PNGase Rc was demonstrated by releasing N-glycans from a diverse array of samples such as peach fruit, king trumpet mushroom, mouse serum, and the soil nematode Caenorhabditis elegans. The presence of only two disulfide bonds shown in the AlphaFold protein model (so far all other superacidic PNGases possess more disulfide bonds) could be corroborated by intact mass- and peptide mapping analysis and provides a possible explanation for the improved recombinant expression yield of PNGase Rc.

Association between patterns of eating habits and mental health problems in Chinese adolescents: A latent class analysis.

Objective: We aimed to investigate the association between different eating habit patterns and mental health problems among Chinese middle and high school students, and further to estimate the interaction effect of different grouping variables on eating habits. Methods: One thousand three hundred and forty-eight adolescents from Jilin Province in China were involved in this cross-sectional study. Mental health and eating habits were assessed using General Health Questionnaire and questions on Nutrition Knowledge, Attitude and Practice, respectively. Latent class analysis (LCA) was performed to identify eating habit patterns. Binary logistic regression and generalized linear models were used to explore the association between eating habit patterns, energy-adjusted nutrient intakes and mental health problems. Interaction analysis was performed to analyze the association between eating habits and mental health in different groups. Results: Based on the LCA results, a 3-class parallel model was identified: 648 adolescents (48.1%) were classified in class-1 "Healthy Eating Behavior/Eating at Home," 452 adolescents (33.5%) in class-2 "Healthy Eating Behavior/Eating at School" and 248 adolescents (18.4%) in class-3 "Unhealthy Eating Behavior/Random Place." Compared with class-1, participants in class-2 and class-3 were at higher risk of mental health problems, especially for class-3 (p < 0.05). The energy and nutrient intakes by different latent classes showed that adolescents who ate unhealthy had lower daily intake of energy, protein, carbohydrate, fiber, Vitamins and minerals (p < 0.05). The interaction between age, sleep duration and different eating habits was statistically significant (p for interaction < 0.1). Conclusion: "Unhealthy eating behavior/random place pattern" was positively correlated with mental health problems of adolescents. The adolescents with health diet were accompanied by fewer mental health problems, especially for that eating at home. And there were interactions between eating habits and age, sleep duration on the mental health problems.