VLGR1/ADGRV1 (very large G protein-coupled receptor-1) is the largest known adhesion G protein-coupled receptor. Mutations in VLGR1/ADGRV1 cause Usher syndrome (USH), the most common form of hereditary deaf-blindness, and have been additionally linked to epilepsy. Although VLGR1/ADGRV1 is almost ubiquitously expressed, little is known about the subcellular function and signalling of the VLGR1 protein and thus about mechanisms underlying the development of diseases. Using affinity proteomics, we have identified key components of autophagosomes as putative interacting proteins of VLGR1. In addition, whole transcriptome sequencing of the retinae of the Vlgr1/del7TM mouse model revealed altered expression profiles of gene-related autophagy. Monitoring autophagy by immunoblotting and immunocytochemistry of the LC3 and p62 as autophagy marker proteins revealed evoked autophagy in VLGR1-deficient hTERT-RPE1 cells and USH2C patient-derived fibroblasts. Our data demonstrate the molecular and functional interaction of VLGR1 with key components of the autophagy process and point to an essential role of VLGR1 in the regulation of autophagy at internal membranes. The close association of VLGR1 with autophagy helps to explain the pathomechanisms underlying human USH and epilepsy-related to VLGR1 defects.

VLGR1/ADGRV1 (very large G protein-coupled receptor-1) is the largest adhesion G protein-coupled receptor aGPCRs. Mutations in VLGR1/ADGRV1 are associated with human Usher syndrome (USH), the most common form of deaf-blindness, and also with epilepsy in humans and in mice. Although VLGR1 is almost ubiquitously expressed in CNS and ocular and inner ear sensory cells. Little is known about the pathogenesis of the diseases related to VLGR1. We previously identified VLGR1 as a vital component of focal adhesions (FA) serving as a metabotropic mechanoreceptor that controls cell spreading and migration. FAs are highly dynamic and turnover frequently in response to internal and external signals. Here, we aimed to elucidate how VLGR1 participates in FA turnover. Nocodazole washout assays and live-cell imaging of RFP-paxillin consistently demonstrated that FA disassembly was not altered, de novo assembly of FA was significantly delayed in Vlgr1-deficient astrocytes indicating that VLGR1 is enrolled in the assembly of FAs. In FRAP experiments recovery rates were significantly reduced in Vlgr1-deficient FAs, indicating reduced turnover kinetics in VLGR1-deficient FAs. We showed that VLGR1 regulates cell migration by controlling the FA turnover during their assembly. From this, we expect novel insights into pathomechanisms related to pathogenic dysfunctions of VLGR1.

The present study evaluates the influence of type 2 diabetes (T2D) on important CYP450 isoforms and P-glycoprotein (P-gp) transporter activities before and 3 months after intensifying treatment regimen of 40 patients. Results have been compared with 21 non-T2D healthy participants (control group). CYPs and P-gp activities were assessed after administration of Geneva cocktail. Mean metabolic ratios (MR) for CYP2B6 (1.81±0.93 vs. 2.68±0.87), CYP2C19 (0.420 ± 0.360 vs. 0.687 ± 0.558), and CYP3A4/5 (0.487 ± 0.226 vs. 0.633 ± 0.254) significantly decreased in T2D subjects compared to control group (p<0.05). CYP2C9 (0.089±0.037 vs. 0.069±0.017) activities slightly increased in diabetic subjects and no difference was observed for CYP1A2 (0.154±0.085 vs. 0.136±0.065), CYP2D6 (1.17 ± 0.56 vs. 1.24 ± 0.83) and P-gp activities in comparison with control group. Three months after intensifying treatment regimen, MRs of CYP2C9 (0.080 ± 0.030) and CYP3A4/5 (0.592 ± 0.268) have shown a significant improvement and were not statistically different compared to control group (P>0.05). Several covariables such as inflammatory markers (IL-1β and IL-6), genotypes, diabetes- and demographic-related factors were considered in our analyses. Our results indicate that low chronic inflammatory status associated with T2D modulates CYP450 activities in an isoform specific manner.

4-Methylbenzylidene camphor (4-MBC) is a photo-absorbing UV filter, which can be absorbed into the circulation and cause systemic effects. 4-MBC is found extensively in the environment and measurements suggest bioaccumulation in human tissues. 4-MBC is continued to be released in the environment despite the growing knowledge about its potential endocrine and reproductive disrupting effects. 4-MBC interfers with various processes, such as placental development, spermatogenesis, and inflammatory cascades. Previous reviews mention 4-MBC as one of the several UV filters but here we focus on 4-MBC only. We cover the potential effects on human health regarding systemic and molecular effects, with the focus on reproduction. We also cover the potential bioaccumulation and interactions with receptor systems, such as the estrogen receptors β and α, and progesterone receptor, and analyze 4-MBC´s effects on mRNA expression and protein expression. Furthermore, 4-MBC is reported to act with inflammatory pathways by activating p38 MAPK and NF-κB, leading to the production of inflammatory TNF-α and IL-6. In conclusion, 4-MBC has wide ranging effects in different models while there is more research warranted to detail the mechanism of action, long-term effects at low doses and the potential interaction with many pathways and other pollutants.

The role of betaine in the liver and kidney has been well documented, even from the cellular and molecular point of view. Despite literature reporting positive effects of betaine supplementation in Alzheimer’s, Parkinson’s, and Schizophrenia, the role and function of betaine in the brain are little studied and reviewed. Beneficial effects of betaine in neurodegeneration, excitatory and Inhibitory imbalance, and oxidative stress in the central nervous system have been collected and analyzed with the aim of understanding the main role of betaine in the brain. There are many “dark” aspects needed to complete the picture. The understanding of how this osmolyte is transported across neuron and glial cells is also controversial, as the expression levels and functioning of the known protein capable to transport betaine expressed in the brain, betaine-GABA transporter 1 BGT-1, is itself not well clarified. The reported actions of betaine beyond BGT-1 related to neuronal degeneration and memory impairment are the focus of this work. With this review, we underline the scarcity of detailed molecular and cellular information about betaine action. Consequently, the requirement of detailed focus on and study of the interaction of this molecule with CNS components to sustain the therapeutic use of betaine.