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Identification of the tyrosine phosphorylation (pY)-dependent interactome of immune co-receptors is crucial for understanding signal pathways involved in immunotherapy. However, identifying the motif-specific interactome for each pY commonly found on these multi-phosphorylated membrane proteins remains challenging. Here, we describe a photoaffinity-based chemical proteomic approach to dissect the motif-specific cytoplasmic interactomes of the critical immune co-receptor CD28. Various full-length CD28 cytoplasmic tails (CD28cyto) with defined pY and selectively replaced photo-methionine were synthesized and applied to explore three pY-motif-dependent CD28cyto interactomes. We identified a stand-alone interaction of phospholipase PLCG1 with the Y191 motif with enhanced affinity for the sequence neighboring the transmembrane domain. Importantly, taking advantage of native top-down mass spectrometry with a 193-nm laser, we discovered the direct association of a previously undefined pY218 motif with the kinase PKCθ through its C2 domain. This synthetic CD28cyto-based photoaffinity proteomic approach is generically applicable to the study of other immune co-receptors with multiple pY sites on their linear cytoplasmic tail.

Studies have shown that both short-term and long-term cold exposures disturb the biological process. The aim of the present study is to investigate the effects of intermittent cold exposure on proteomic profiles in the hypothalamus and pituitary of female Sprague-Dawley (SD) rats.

Background: Kinesiophobia is common in patients after total knee arthroplasty and is an important risk factor for post-operative recovery outcomes. Little is known about the complex intercorrelations between different components of pain catastrophizing, self-efficacy, and kinesiophobia. This study aimed to identify the central components of kinesiophobia and to explore the interconnectedness between components of pain catastrophizing, self-efficacy, and kinesiophobia. Methods: A total of 216 patients after total knee arthroplasty were recruited in this study. Pain Catastrophizing Scale, Self-efficacy of Rehabilitation Outcome Scale and Tampa Scale for Kinesiophobia were used to assess pain catastrophizing, self-efficacy and kinesiophobia. R software was used to visualize the networks and analyze the centrality of the networks. The index "strength" and "bridge expected influence" were employed to identify the central components and the bridge components of the networks. Results: In the item network of kinesiophobia, three items ("Simply being careful that I do not make any unnecessary movements is the safest thing I can do to prevent my pain from worsening", "My accident has put my body at risk for the rest of my life", and "My body is telling me I have something dangerously wrong") had the highest strength centrality. In the pain catastrophizing/self-efficacy–kinesiophobia network, rumination had the highest positive bridge expected influence, while coping self-efficacy had the highest negative value. Conclusion: The three central components of kinesiophobia identified in this study, as well as two bridge variables (rumination and coping self-efficacy), could be promising and effective targets for prevention and intervention of kinesiophobia. [ABSTRACT FROM AUTHOR]

BACKGROUND: Moringa oleifera (M. oleifera) leaves are rich in nutrients and bioactive ingredients. This study was aimed at evaluating the anti‐fatigue effect of the ethanol extract of M. oleifera leaves (MLEE) on mice and its primary mechanism of action using a weight‐loaded forced swimming test. In the present study, MLEE was prepared by ultrasound‐assisted extraction, and its anti‐fatigue effect and antioxidant capacity were evaluated in mice. Mice were administrated MLEE (320 mg kg−1 body weight) for 15 days. RESULTS: MLEE supplementation significantly increased levels of glucose and non‐esterified fatty acids (NEFA), while decreasing levels of lactate and blood urea nitrogen in serum (P < 0.05); the levels of glycogen in the liver and muscle were also increased, as was the activity of glycogen synthase and the level of NEFA in muscle (P < 0.05). According to a Western blot analysis, MLEE increased the expression of AMPKα1, JNK, AKT and STAT3 in the muscle of mice. CONCLUSION: Our findings indicate that MLEE has an anti‐fatigue effect via the AMPK‐linked route, which enables it to control energy metabolism and enhance antioxidant enzyme activity. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

A fully integrated sample preparation technology, termed Intact GlycoSISPROT, was developed for the highly sensitive analysis of site-specific glycopeptides. Through integrating all glycoproteomic sample preparation steps into a single spintip, Intact GlycoSISPROT provided a tool for site-specific glycosylation analysis with low micrograms to even nanograms of protein sample. [ABSTRACT FROM AUTHOR]

Background: Sepsis-associated encephalopathy (SAE) is the most severe complication of sepsis. Ubiquitin-specific protease 8 (USP8) could improve cognitive and motor disorders in SAE., Objective: This study explored the mechanism of USP8 in SAE mice to provide new therapeutic targets for SAE., Methods: C57BL/6 mice were selected to establish SAE models by caecal ligation and puncture (CLP) and injected with lentivirus overexpressing USP8 one week before SAE modeling. Mouse weight changes were monitored, cognitive and learning abilities were tested by the Morris water maze test, behaviors were evaluated by open-field tests, and pathological changes in brain tissue were analyzed by H&E staining. Levels of USP8, TNF-α, IL-1β, IL-6, and IL-10, and SOD, GSH-Px activities, and MDA levels were detected by Western blot, ELISA, and kits. Co-immunoprecipitation assay verified the interaction between USP8 and SIRT1 and SIRT1 ubiquitination level., Results: In CLP mice, the body weight, cognitive function, and learning ability were decreased, along with motor disorder, abnormal morphological structure of neurons, and obvious inflammatory infiltration. USP8 protein in brain tissue was decreased, the levels of TNF-α, IL-1β, and IL-6 were increased, IL-10 was decreased, SOD and GSH-Px activities were decreased, and MDA level was increased. USP8 treatment improved cognitive dysfunction and inhibited inflammation and oxidative stress in CLP mice. USP8 promoted SIRT1 expression by direct deubiquitination. SIRT1 knockdown partially reversed the regulation of USP8 on SAE mice., Conclusion: USP8 can directly deubiquitinate SIRT1 and inhibit inflammatory reactions and oxidative stress, thus improving cognitive dysfunction in SAE mice., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)