Phloridzin improves lipoprotein lipase activity in stress-loaded mice via AMPK phosphorylation

Dietary B group vitamin intake and the bladder cancer risk: a pooled analysis of prospective cohort studies

PURPOSE

Diet may play an essential role in the aetiology of bladder cancer (BC). The B group complex vitamins involve diverse biological functions that could be influential in cancer prevention. The aim of the present study was to investigate the association between various components of the B group vitamin complex and BC risk.

METHODS

Dietary data were pooled from four cohort studies. Food item intake was converted to daily intakes of B group vitamins and pooled multivariate hazard ratios (HRs), with corresponding 95% confidence intervals (CIs), were obtained using Cox-regression models. Dose-response relationships were examined using a nonparametric test for trend.

RESULTS

In total, 2915 BC cases and 530,012 non-cases were included in the analyses. The present study showed an increased BC risk for moderate intake of vitamin B1 (HRB1: 1.13, 95% CI: 1.00-1.20). In men, moderate intake of the vitamins B1, B2, energy-related vitamins and high intake of vitamin B1 were associated with an increased BC risk (HR (95% CI): 1.13 (1.02-1.26), 1.14 (1.02-1.26), 1.13 (1.02-1.26; 1.13 (1.02-1.26), respectively). In women, high intake of all vitamins and vitamin combinations, except for the entire complex, showed an inverse association (HR (95% CI): 0.80 (0.67-0.97), 0.83 (0.70-1.00); 0.77 (0.63-0.93), 0.73 (0.61-0.88), 0.82 (0.68-0.99), 0.79 (0.66-0.95), 0.80 (0.66-0.96), 0.74 (0.62-0.89), 0.76 (0.63-0.92), respectively). Dose-response analyses showed an increased BC risk for higher intake of vitamin B1 and B12.

CONCLUSION

Our findings highlight the importance of future research on the food sources of B group vitamins in the context of the overall and sex-stratified diet.

The Bioavailability, Extraction, Biosynthesis and Distribution of Natural Dihydrochalcone: Phloridzin

Phloridzin is an important phytochemical which was first isolated from the bark of apple trees. It is a member of the dihydrochalcones and mainly distributed in the plants of the Malus genus, therefore, the extraction method of phloridzin was similar to those of other phenolic substances. High-speed countercurrent chromatography (HSCCC), resin adsorption technology and preparative high-performance liquid chromatography (HPLC) were used to separate and purify phloridzin. Many studies showed that phloridzin had multiple pharmacological effects, such as antidiabetic, anti-inflammatory, antihyperglycaemic, anticancer and antibacterial activities. Besides, the physiological activities of phloridzin are cardioprotective, neuroprotective, hepatoprotective, immunomodulatory, antiobesity, antioxidant and so on. The present review summarizes the biosynthesis, distribution, extraction and bioavailability of the natural compound phloridzin and discusses its applications in food and medicine.

Autophagic degradation of PML promotes susceptibility to HSV-1 by stress-induced corticosterone

Rationale: Herpes simplex virus type 1 (HSV-1) is a neurotropic virus that can cause a variety of clinical syndromes including mucocutaneous disease and HSV-1 encephalitis (HSE). Here, we characterize the molecular mechanisms underlying the susceptibility to HSV-1 under stressful conditions.

Methods: Restraint stress and corticosterone (CORT, a primary stress hormone) were respectively used to establish HSV-1 susceptible model in vivo and in vitro. Viral titers were determined by plaque assay. Western blotting, immunofluorescence, transmission electron microscopy (TEM), qRT-PCR, H&E staining, IHC staining and flow cytometry were employed to evaluate virus-related protein expressions and detect the activation of autophagy. Loss- and gain-function assays, co-immunoprecipitation (co-IP) technique and autophagy agonist/antagonist treatments were applied in mechanistic experiments.

Results: Restraint stress increased the susceptibility of mouse brain to HSV-1. Similarly, CORT treatment enhanced the susceptibility of neural cells to HSV-1. Furthermore, PML protein level in HSV-1 infected brain tissues and neural cells was remarkably decreased by stress treatment in vivo or CORT treatment in vitro, while its transcriptional level was not affected. Notably, a striking decline in protein expressions of ICP27 and gB was observed in PML-overexpressing cells, which was reversed by CORT treatment. By contrast, protein expression of gB was increased by knockdown with si-PML in virus-infected SH-SY5Y cells. We further discovered that CORT-driven PML degradation was dependent on the activation of autophagy in a ULK1-independent manner, rather than proteasome pathway. Bafilomycin A1 (BaF1) attenuated the augmentation effect of CORT on HSV-1 infection. The expressions of viral proteins were reduced in LC3-depleted cells, and the degradation of PML by CORT-induced autophagy was prevented in cells with LC3 knockdown by RNAi. Interestingly, PML was revealed to interact with the autophagic cargo receptor P62 and the autophagic effector protein LC3. Additionally, CORT failed to increase gB protein level when PML was silenced, providing direct evidence linking autophagic degradation of PML and CORT-induced virus susceptibility.

Conclusion: Our results revealed that restraint stress/CORT increased HSV-1 susceptibility by delivering PML into autolysosomes for degradation. The results obtained from in vitro and in vivo models not only demonstrated the adverse effects of stress on HSV-1 infection, but also systematically investigated the underlying molecular mechanisms. These discoveries broaden our understanding of the interplay between host and viruses, and a comprehensive understanding of the role of autophagy in viral infection will provide information for future development of innovative drugs against viral infection.

Triglyceride metabolism and angiopoietin-like proteins in lipoprotein lipase regulation

Hypertriglyceridemia is a risk factor for a series of diseases, such as cardiovascular disease (CVD), diabetes and nonalcoholic fatty liver disease (NAFLD). Angiopoietin-like proteins (ANGPTLs) family, especially ANGPTL3, ANGPTL4 and ANGPTL8, which regulate lipoprotein lipase (LPL) activity, play pivotal roles in triglyceride (TG) metabolism and related diseases/complications. There are many transcriptional and post-transcriptional factors that participate in physiological and pathological regulation of ANGPTLs to affect triglyceride metabolism. This review is intended to focus on the similarity and difference in the expression, structural features, regulation profile of the three ANGPTLs and inhibitory models for LPL. Description of the regulatory factors of ANGPTLs and the properties in regulating the lipid metabolism involved in the underlying mechanisms in pathological effects on diseases will provide potential therapeutic approaches for the treatment of dyslipidemia related diseases.