Lysosome blockade induces divergent metabolic programs in macrophages and tumours for cancer immunotherapy.

BACKGROUND: Platinum-drugs based chemotherapy in clinic increases the potency of tumor cells to produce M2 macrophages, thus leading to poor anti-metastatic activity and immunosuppression. Lysosome metabolism is critical for cancer cell migration and invasion, but how it promotes antitumor immunity in tumours and macrophages is poorly understood and the underlying mechanisms are elusive. The present study aimed to explore a synergistic strategy to dismantle the immunosuppressive microenvironment of tumours and metallodrugs discovery by using the herent metabolic plasticity. METHODS: Naphplatin was prepared by coordinating an active alkaline moiety to cisplatin, which can regulate the lysosomal functions. Colorectal carcinoma cells were selected to perform the in vivo biological assays. Blood, tumour and spleen tissues were collected and analyzed by flow cytometry to further explore the relationship between anti-tumour activity and immune cells. Transformations of bone marrow derived macrophage (BMDM) and M2-BMDM to the M1 phenotype was confirmed after treatment with naphplatin. The key mechanisms of lysosome-mediated mucolipin-1(Mcoln1) and mitogen-activated protein kinase (MAPK) activation in M2 macrophage polarization have been unveiled. RNA sequencing (RNA-seq) was used to further explore the key mechanism underlying high-mobility group box 1(HMGB1)-mediated Cathepsin L(CTSL)-lysosome function blockade. RESULTS: We demonstrated that naphplatin induces divergent lysosomal metabolic programs and reprograms macrophages in tumor cells to terminate the vicious tumour-associated macrophages (TAMs)-MDSCs-Treg triangle. Mechanistically, macrophages treated with naphplatin cause lysosome metabolic activation by triggering Ca2+ release via Mcoln1, which induces the activation of p38 and nuclear factor-κB (NF-κB) and finally results in polarizing M2 macrophages. In contrast, HMGB1-mediated lysosome metabolic blockade in cancer cells is strongly linked to antitumor effects by promoting cytoplasmic translocation of HMGB1. CONCLUSIONS: This study reveals the crucial strategies of macrophage-based metallodrugs discovery that are able to treat both immunologically "hot" and "cold" cancers. Different from traditional platinum-based antitumour drugs by inhibition of DNAs, we also deliver a strong antitumour strategy by targeting lysosome to induce divergent metabolic programs in macrophages and tumours for cancer immunotherapy.

Associations of healthful and unhealthful plant-based diets with plasma markers of cardiometabolic risk.

PURPOSE: Plant-based diets, particularly when rich in healthy plant foods, have been associated with a lower risk of type 2 diabetes and cardiovascular disease. However, the impact of plant-based diets that distinguish between healthy and unhealthy plant foods on cardiometabolic biomarkers remains unclear. METHODS: Dietary information was collected by two 24-h recalls among 34,785 adults from a nationwide cross-sectional study. Plasma levels of insulin, C-peptide, glucose, C-reactive protein (CRP), white blood cell (WBC) count, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) were measured. Linear regression was used to evaluate the percentage difference in plasma marker concentrations by three plant-based diet indices, namely the overall plant-based diet index (PDI), the healthful PDI (hPDI), and the unhealthful PDI (uPDI). RESULTS: Greater hPDI-adherence scores (comparing extreme quartiles) were associated with lower levels of insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), TG/HDL-C ratio, CRP, WBC count, and TG, and higher levels of HDL-C, with the percentage differences of - 14.55, - 15.72, - 11.57, - 14.95, - 5.26, - 7.10, and 5.01, respectively (all Ptrend ≤ 0.001). Conversely, uPDI was associated with higher levels of insulin, C-peptide, HOMA-IR, TG/HDL-C ratio, CRP, WBC count, and TG, but lower HDL-C, with the percentage differences of 13.71, 14.00, 14.10, 10.43, 3.32, 8.00, and - 4.98 (all Ptrend ≤ 0.001), respectively. Overall PDI was only associated with lower levels of CRP and WBC count (all Ptrend ≤ 0.001). CONCLUSION: Our findings suggest that hPDI may have positive, whereas uPDI may have negative impacts on multiple cardiometabolic risk markers, and underscore the need to consider the quality of plant foods in future PDI studies.

Association between time-restricted eating and non-alcoholic fatty liver disease in a nationwide cross-sectional study.

The association between time-restricted eating (TRE) and the risk of non-alcoholic fatty liver disease (NAFLD) is less studied. Moreover, whether the association is independent of physical exercise or diet quality or quantity is uncertain. In this nationwide cross-sectional study of 3813 participants, the timing of food intakes was recorded by 24-h recalls; NAFLD was defined through vibration-controlled transient elastography in the absence of other causes of chronic liver disease. OR and 95 % CI were estimated using logistic regression. Participants with daily eating window of ≤ 8 h had lower odds of NAFLD (OR = 0·70, 95 % CI: 0·52, 0·93), compared with those with ≥ 10 h window. Early (05.00-15.00) and late TRE (11.00-21.00) showed inverse associations with NAFLD prevalence without statistical heterogeneity (Pheterogeneity = 0·649) with OR of 0·73 (95 % CI: 0·36, 1·47) and 0·61 (95 % CI: 0·44, 0·84), respectively. Such inverse association seemed stronger in participants with lower energy intake (OR = 0·58, 95 % CI: 0·38, 0·89, Pinteraction = 0·020). There are no statistical differences in the TRE-NAFLD associations according to physical activity (Pinteraction = 0·390) or diet quality (Pinteraction = 0·110). TRE might be associated with lower likelihood of NAFLD. Such inverse association is independent of physical activity and diet quality and appears stronger in individuals consuming lower energy. Given the potential misclassification of TRE based on one- or two-day recall in the analysis, epidemiological studies with validated methods for measuring the habitual timing of dietary intake are warranted.

Ac34FGlcNAz is an effective metabolic chemical reporter for O-GlcNAcylated proteins with decreased S-glyco-modification.

O-GlcNAcylation is a ubiquitous post-translational modification governing vital biological processes in cancer, diabetes and neurodegeneration. Metabolic chemical reporters (MCRs) containing bio-orthogonal groups such as azido or alkyne, are widely used for labeling of interested proteins. However, most MCRs developed for O-GlcNAc modification are not specific and always lead to unexpected side reactions termed S-glyco-modification. Here, we attempt to develop a new MCR of Ac34FGlcNAz that replacing the 4-OH of Ac4GlcNAz with fluorine, which is supposed to abolish the epimerization of GALE and enhance the selectivity. The discoveries demonstrate that Ac34FGlcNAz is a powerful MCR for O-GlcNAcylation with high efficiency and the process of this labeling is conducted by the two enzymes of OGT and OGA. Most importantly, Ac34FGlcNAz is predominantly incorporated intracellular proteins in the form of O-linkage and leads to negligible S-glyco-modification, indicating it is a selective MCR for O-GlcNAcylation. Therefore, we reason that Ac34FGlcNAz developed here is a well characterized MCR of O-GlcNAcylation, which provides more choice for label and enrichment of O-GlcNAc associated proteins.

Healthy and unhealthy low-carbohydrate diets and plasma markers of cardiometabolic risk.

Previous studies have reported inconsistent associations between low-carbohydrate diets (LCD) and plasma lipid profile. Also, there is little evidence on the role of the quality and food sources of macronutrients in LCD in cardiometabolic health. We investigated the cross-sectional associations between LCD and plasma cardiometabolic risk markers in a nationwide representative sample of the US population. Diet was measured through two 24-h recalls. Overall, healthy (emphasising unsaturated fat, plant protein and less low-quality carbohydrates) and unhealthy (emphasising saturated fat, animal protein and less high-quality carbohydrate) LCD scores were developed according to the percentage of energy as total and subtypes of carbohydrate, protein and fat. Linear regression was used to estimate the percentage difference of plasma marker concentrations by LCD scores. A total of 34 785 participants aged 18-85 years were included. After adjusting for covariates including BMI, healthy LCD was associated with lower levels of insulin, homoeostatic model assessment for insulin resistance (HOMA-IR), C-reactive protein (CRP) and TAG, and higher levels of HDL-cholesterol, with the percentage differences (comparing extreme quartile of LCD score) of -5·91, -6·16, -9·13, -9·71 and 7·60 (all Ptrend < 0·001), respectively. Conversely, unhealthy LCD was associated with higher levels of insulin, HOMA-IR, CRP and LDL-cholesterol (all Ptrend < 0·001). Our results suggest that healthy LCD may have positive, whereas unhealthy LCD may have negative impacts on CRP and metabolic and lipid profiles. These findings underscore the need to carefully consider the quality and subtypes of macronutrients in future LCD studies.

A Healthful Plant-Based Diet Is Associated with Lower Odds of Nonalcoholic Fatty Liver Disease.

There is little evidence for the associations of the overall plant-based diet index (PDI), the healthful PDI (hPDI), and the unhealthful PDI (uPDI) with the odds of nonalcoholic fatty liver disease (NAFLD). We present a nationwide cross-sectional study among US adults aged 18 years or older. Diet was assessed by 24-h recalls. Overall PDI, hPDI, and uPDI were constructed based on 18 food groups. NAFLD was defined based on controlled attenuation parameter derived via transient elastography (TE) in the absence of other causes of chronic liver disease. Among 3900 participants with eligible TE examination, 1686 were diagnosed with NAFLD. The overall PDI was not associated with NAFLD prevalence (comparing extreme tertiles of PDI score OR = 1.03, 95% CI 0.76, 1.38, ptrend = 0.609). However, hPDI was inversely (OR = 0.50, 95% CI 0.35, 0.72, ptrend < 0.001), while uPDI was positively associated with odds of NAFLD (OR = 1.37, 95% CI 0.93, 2.02, ptrend = 0.009) in the multivariable-adjusted models without body mass index (BMI). After further adjustment for BMI, only the association of hPDI with NAFLD remained statistically significant (OR = 0.64, 95% CI 0.46, 0.87, ptrend = 0.006). Such inverse association appeared stronger in non-Hispanic whites, but not in other racial/ethnic groups (pinteraction = 0.009). Our findings suggest that a plant-based diet rich in healthy plant foods might be associated with lower odds of NAFLD, particularly among US non-Hispanic whites. Clinical trials and cohort studies to validate our findings are needed.

Associations between low-carbohydrate and low-fat diets and hepatic steatosis.

OBJECTIVE: This study assessed the cross-sectional associations of low-carbohydrate diets (LCDs) and low-fat diets (LFDs) with hepatic steatosis in the National Health and Nutrition Examination Survey. METHODS: Diet was measured using the 24-hour recalls. Hepatic steatosis was defined by vibration-controlled transient elastography. The odds ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression. Substitution analysis was performed using the leave-one-out model. RESULTS: Participants with higher adherence scores (comparing extreme tertiles) for an overall (OR = 0.76, 95% CI: 0.61-0.96, ptrend  = 0.049) or a healthful LCD (OR = 0.61, 95% CI: 0.43-0.87, ptrend < 0.001) exhibited lower odds of steatosis. Replacing 5% of the energy from carbohydrates with total fat and protein (OR = 0.91, 95% CI: 0.83-0.99) or unsaturated fat and plant protein (OR = 0.89, 95% CI: 0.84-0.94) was associated with lower steatosis prevalence. High overall (OR = 1.65, 95% CI: 1.13-2.40, ptrend  = 0.006) or unhealthful (OR = 1.41, 95% CI: 1.10-1.80, ptrend < 0.001) LFD scores were associated with increased likelihood of steatosis. CONCLUSIONS: These findings suggest that the associations between LCDs and LFDs and steatosis may depend on the quality and food sources of the macronutrients.

Associations between intake of starchy and non-starchy vegetables and risk of hepatic steatosis and fibrosis.

BACKGROUND: Current dietary guidelines generally treat all types of vegetables the same. However, whether specific vegetables are more beneficial or deleterious for preventing chronic liver disease (CLD) remains uncertain. METHODS: We investigated the associations between starchy and non-starchy vegetables and the odds of hepatic steatosis and fibrosis in a US nationwide cross-sectional study. Diet was assessed by the 24-h dietary recalls. Hepatic steatosis and fibrosis were defined based on vibration-controlled transient elastography (TE). Multiple logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among 4170 participants with reliable TE test, 1436 were diagnosed with steatosis, 255 with advanced fibrosis. Increased intake of total starchy vegetables was associated with higher odds of steatosis (OR per 1-SD increment 1.11, 95% CI 1.01-1.24) and advanced fibrosis (OR = 1.39, 95% CI 1.15-1.69). Similar positive associations were observed for potatoes. Conversely, intakes of total non-starchy (OR = 0.82, 95% CI 0.71-0.95) and dark-green vegetables (OR = 0.89, 95% CI 0.82-0.97) were inversely associated with steatosis prevalence. Replacing 5% of energy from starchy vegetables (OR = 0.65, 95% CI 0.44-0.97) or potatoes (OR = 0.65, 95% CI 0.43-0.97) with equivalent energy from dark-green vegetables was associated with lower odds of steatosis. CONCLUSIONS: These findings support the recommendation to limit starchy vegetable intake and increase non-starchy vegetable intake in CLD prevention, and provide evidence for the potential health benefit from dietary substitution of non-starchy vegetables for starchy vegetables.

A Prospective Study of Fruit Juice Consumption and the Risk of Overall and Cardiovascular Disease Mortality.

There is little evidence for the association between fruit juice, especially 100% fruit juice, and mortality risk. In addition, whether 100% fruit juice can be a healthy alternative to whole fruit remains uncertain. This prospective study utilized the data from the US National Health and Nutrition Examination Survey (NHANES) from 1999 to 2014. After a median follow-up of 7.8 years, 4904 deaths among 40,074 participants aged 18 years or older were documented. Compared to non-consumption, daily consumption of 250 g or more of 100% fruit juice was associated with higher overall mortality (hazard ratio (HR) = 1.30, 95% confidence interval (CI): 1.11-1.52) and mortality from heart disease (HR = 1.49, 95 CI: 1.01-2.21). A similar pattern was observed for total fruit juice, with HRs of 1.28 (95% CI: 1.09-1.49) for overall mortality and 1.48 (95% CI: 1.01-2.17) for heart disease mortality. Replacing 5% of energy from whole fruit with 100% or total fruit juice was associated with a 9% (95% CI: 2-16%) and 8% (95% CI: 1-15%) increased mortality risk, respectively. Our findings suggest that both total and 100% fruit juice could be associated with high mortality risk, and need to be validated in well-designed studies given the potential misclassification of diet and death reasons.

The Metabolic Chemical Reporter Ac46AzGal Could Incorporate Intracellular Protein Modification in the Form of UDP-6AzGlc Mediated by OGT and Enzymes in the Leloir Pathway.

Galactose is a naturally occurring monosaccharide used to build complex glycans that has not been targeted for labeling as a metabolic reporter. Here, we characterize the cellular modification of proteins by using Ac46AzGal in a dose- and time-dependent manner. It is noted that a vast majority of this labeling of Ac46AzGal occurs intracellularly in a range of mammalian cells. We also provided evidence that this labeling is dependent on not only the enzymes of OGT responsible for O-GlcNAcylation but also the enzymes of GALT and GALE in the Leloir pathway. Notably, we discover that Ac46AzGal is not the direct substrate of OGT, and the labeling results may attribute to UDP-6AzGlc after epimerization of UDP-6AzGal via GALE. Together, these discoveries support the conclusion that Ac46AzGal as an analogue of galactose could metabolically label intracellular O-glycosylation modification, raising the possibility of characterization with impaired functions of the galactose metabolism in the Leloir pathway under certain conditions, such as galactosemias.

Synthesis of Na2S2O4 mediated cleavable affinity tag for labeling of O-GlcNAc modified proteins via azide-alkyne cycloaddition.

A facile and convergent procedure for the synthesis of azobenzene-based probe was reported, which could selectively release interested proteins conducted with sodium dithionite. Besides, the cleavage efficiency is closely associated with the structural features, in which an ortho-hydroxyl substituent is necessary for reactivity. In addition, the azobenzene tag applied in the Ac4GlcNAz-labled proteins demonstrated high efficiency and selectivity in comparison with Biotin-PEG4-Alkyne, which provides a useful platform for enrichment of any desired bioorthogonal proteomics.