Biochemistry and Biophysics Reports最新文献

The mechanism by which the skin, a non-visual tissue, responds to light remains unknown. To date, opsin expression has been demonstrated in keratinocytes, melanocytes, and fibroblasts, all of which are skin-derived cells. In this study, we examined whether the visual cycle, by which opsin activity is maintained, is present in skin keratinocytes. We also identified the wavelengths of light to which opsin in keratinocytes responds and explored their effects on skin keratinocytes. The fetal rat skin keratinocytes used in this study expressed OPN2, 3, and 5 in addition to enzymes involved in the visual cycle, and all-trans-retinal, which is produced by exposure to light, was reconverted to 11-cis-retinal, resulting in opsin activation. Using the production of all-trans-retinal after light exposure as an indicator, we discovered that keratinocytes responded to light at 450 nm. Furthermore, actin alpha cardiac muscle 1 expression in keratinocytes was enhanced and cell migration was suppressed by exposure to light at these wavelengths. These results indicate that keratinocytes express various opsins and have a visual cycle that keeps opsin active. Moreover, keratinocytes were shown to respond to the blue/UV region of the light spectrum, suggesting that opsin plays a role in the light response of the skin.

Our study focused on specific ChR2 variants, particularly those with the Step function Opsins (SFO) mutation at the D156-C128 gate. These are widely used in optogenetics due to their heightened sensitivity to light and bi-stable prolonged activation. However, in some ChR2 variants, specifically D156 mutants, a tail current occurs when continuous light exposure is stopped. We specifically examined the D156H-T159S ChR2 variant, which demonstrated a tail current that was somewhat responsive to light and voltage, with a single-channel current of around 9fA, similar to wt-ChR2 as determined by stationary noise analysis. To further investigate, we used nonstationary noise analysis in cell-attached patching mode, which revealed that the tail current's single-channel current falls within the same range as the peak current, albeit with mild contamination from adaptation and desensitization. This finding strongly supports the notion that a portion of the ChR2 molecules open or re-open at the end of illumination, leading to further membrane depolarization.

Diospyros batokana (Ebenaceae) is a valuable medicinal plant that grows in the wild in Zambia. The aqua crude plant extract is valuable in treating oxidative stress and microbes-related diseases. In this study, bioactive metabolites from the leaf of the plant were tentatively identified using ultra-high-pressure liquid chromatography tandem high-resolution mass spectrometry (UHPLC-HRMS). Raw LCMS data were processed using MZmine3.6. Pyrenophorol, N-[1-(diethylamino)-3-morpholin-4-ylpropan-2-yl]-2,2-diphenylacetamide, losartan, and isoarthonin, (2E,4E)-N-[2-(4-hydroxyphenyl)ethyl]dodeca-2,4-dienamide were among the many metabolites identified from the plant studied using LCMS-MZmine 3.6. Furthermore, in silico anti-inflammatory molecular docking was applied to the five (5) metabolites with the aim of predicting the ability of the metabolites to inhibit the COX-2 enzyme. The docking simulation for the five metabolites was executed using the Auto-dock tools. The lowest binding energy of the complexes was visualized using Discovery Studio, 2021 Client l molecular viewer. Pyrenophorol, (N-[1-(diethylamino)-3-morpholin-4-ylpropan-2-yl] −2,2-diphenylacetamide) and losartan were found to provide the lowest binding energy to COX-2 compared to the standard anti-inflammatory drug, diclofenac. Furthermore, binding affinities, inhibition constants, and ligand efficiencies demonstrated that pyrenophorol, N-[1-(diethylamino)-3-morpholin-4-ylpropan-2-yl]-2,2-diphenylacetamide, losartan, isoarthonin and (2E,4E)-N-[2-(4-hydroxyphenyl)ethyl]dodeca-2,4-dienamide could be useful as anti-inflammatory drug candidates supporting the traditional uses of D. batokana. However, the bioavailability radar and physicochemical properties only predict losartan, pyrenophorol, and (2E,4E)-N-[2-(4-hydroxyphenyl)ethyl]dodeca-2,4-dienamide to be bioavailable and suitable drug candidates. In silico and ADMET analysis, shows that the five metabolites could be used as anti-inflammatory drugs comparable to the standard drugs, diclofenac and ibuprofen. However, in vitro and in vivo studies are needed to further support our findings.

Myriocin is an inhibitor of serine palmitoyltransferase involved in the initial biosynthetic step for sphingolipids, and causes potent growth inhibition in eukaryotic cells. In budding yeast, Rsb1, Rta1, Pug1, and Ylr046c are known as the Lipid-Translocating Exporter (LTE) family and believed to contribute to export of various cytotoxic lipophilic compounds. It was reported that Rsb1 is a transporter responsible for export of intracellularly accumulated long-chain bases, which alleviate the cytotoxicity. In this study, it was found that LTE family genes are involved in determination of myriocin sensitivity in yeast. Analyses of effects of deletion and overexpression of LTE family genes suggested that all LTEs contribute to suppression of cytotoxicity of myriocin. It was confirmed that RSB1 overexpression suppressed reduction in complex sphingolipid levels caused by myriocin treatment, possibly exporting myriocin to outside of the cell. These results suggested that LTE family genes function as a defense mechanism against myriocin.

Cancer is the second leading cause of death worldwide, according to the World Health Organization, surpassed only by cardiovascular diseases. Early identification and intervention can significantly improve outcomes. However, finding a universal, non-invasive, economical, and precise method for early cancer detection remains a significant challenge. This study explores the efficacy of an innovative cancer detection test, N-NOSE, leveraging a Caenorhabditis elegans olfactory assay on urine samples across a diverse patient group exceeding 1600 individuals diagnosed with various cancers, with samples from the Shikoku Cancer Center (Ehime, Japan) under approved ethical standards. Current cancer screening techniques often require invasive procedures, can be painful or complex, with poor performance, and might be prohibitively costly, limiting accessibility for many. N-NOSE addresses these challenges head-on by offering a test based on urine analysis, eliminating the need for invasive methods, and being more affordable with higher performance at early stages than extensive blood tests or comprehensive body scans for cancer detection. In this study, N-NOSE demonstrated a capability to accurately identify upwards of 20 cancer types, achieving detection sensitivities between 60 and 90 %, including initial-stage cancers. The findings robustly advocate for N-NOSE's potential as a revolutionary, cost-effective, and minimally invasive strategy for broad-spectrum early cancer detection. It is also particularly significant in low- and middle-income countries with limited access to advanced cancer diagnostic methods, which may contribute to the improved outcome of affected individuals.

The most prevalent cyanotic congenital heart disease, Tetralogy of Fallot (TOF), has an unknown etiology. Long-stranded non-coding RNAs (lncRNAs) have been linked to cardiac development and congenital heart disease, as evidenced by an increasing number of studies; nevertheless, additional research is necessary to fully understand the function that TOF-related lncRNAs play in the condition. This study constructed lncRNA-mRNA co-expression networks, performed functional enrichment analysis, and screened hub lncRNAs using Weighted Gene Co-expression Network Analysis (WGCNA) using the Gene Expression Omnibus dataset GSE36761. Ten hub lncRNAs, including IRF1-AS1, AC012360.6, HLA-F-AS1, RP1-253P7.4, NPTN-IT1, RP11–166P13.4, RP5-1183I21.2, SNHG14, CH17-98J9.1, and RP11–894P9.1, were identified by WGCNA analysis as potentially significant contributors to the development of TOF. Based on functional enrichment analysis, lncRNA mainly contributes to TOF by altering gene splicing patterns. New insights on the mechanism underlying TOF occurrence are provided by identifying hub lncRNAs associated with the disease and analyzing their regulatory networks.

Cxcr4a is involved in multiple organ development including coronary vasculature formation and heart left-right (LR) patterning, whether it is involved in heart progenitor determination and cardiac rhythm regulation is not addressed. Here we showed that in cxcr4a mutants, from 2 days post fertilization (dpf) to 4dpf the embryos transiently displayed pericardial edema and increased cardiac rhythm. While from 5dpf, the heart phenotype disappeared. Detailed analysis demonstrated that, at 36hpf and 48hpf, even though there was no distinct difference in the heart size between cxcr4a mutants and controls, the expression of myl7 was decreased. Further data showed that, the heart progenitors were decreased at 18SS(Somite Stage). Mechanically, RNA-seq, RT-qPCR and in situ experiments showed that the retinoic acid (RA) signaling was upregulated, and the up-regulation of RA signaling may mediate the role of cxcr4a in regulating heart progenitor development. In addition, we also identified that low dose of RA treatment accelerated the cardiac rhythm, being similar to that in cxcr4a mutants. Decreasing RA signaling partially restored the rapid cardiac rhythm in cxcr4a mutants, implying the possibility that RA signaling partially mediates the role of cxcr4a in regulating cardiac rhythm. In conclusion, our study identified cxcr4a simultaneously regulates heart progenitor determination and cardiac rhythm.

Non-alcoholic fatty liver disease (NAFLD) is associated with abnormal bone metabolism, potentially mediated by elevated levels of proinflammatory cytokines such as tumor necrosis factor alpha (TNF-ɑ) and interleukin 6 (IL-6). This study aims to investigate the direct regulatory effects of liver tissues on osteoblast and osteoclast functions in vitro, focusing on the liver-bone axis in NAFLD. Twelve-week-old C57BL/6 mice were fed either a control diet or a high-fat diet (HFD) for 12 weeks. Bone structural parameters were assessed using microCT. Primary hepatocyte cultures were established from control and HFD-fed C57BL/6 mice, as well as IL-6^−/− and TNF-α^−/− mice. The supernatants from these hepatocyte cultures were used to induce differentiation in bone marrow cell-derived osteoblasts and osteoclasts in vitro. Results showed that mice on a HFD exhibited increased lipid infiltration in liver and bone marrow tissues, alongside reduced bone mass. Moreover, the supernatants from hepatocyte cultures from mice on a HFD displayed elevated TNF-α and IL-6 levels. These supernatants, particularly those derived from HFD-fed and IL-6^−/− mice, significantly enhanced osteoclast differentiation in vitro. In contrast, supernatants from TNF-α^−/− mice did not significantly affect osteoblast or osteoclast differentiation in vitro. In conclusions, this current study suggested that fatty liver tissues may negatively impact bone metabolism. Additionally, knockout of TNF-α and IL-6 genes revealed distinct influence on osteoblast and osteoclast functions, highlighting the complex interplay between live pathology and bone health.

Alzheimer's disease (AD) is the most widespread and irreversible form of dementia and accounts for more than half of dementia cases. The most significant risk factors for AD are aging-related exacerbations, degradation of anatomical pathways, environmental variables and mitochondrial dysfunction. Finding a decisive therapeutic solution is a major current issue. Nuanced interactions between major neuropathological mechanisms in AD in patients and microbiome have recently gained rising attention. The presence of bacterial amyloid in the gut triggers the immune system, resulting in increased immune feedbacks and endogenous neuronal amyloid within the CNS. Also, early clinical research revealed that changing the microbiome with beneficial bacteria or probiotics could affect brain function in AD. New approaches focus on the possible neuroprotective action of disease-modifying medications in AD. In the present review, we discuss the impact of the gut microbiota on the brain and review emerging research that suggests a disruption in the microbiota-brain axis can affect AD by mediating neuroinflammation. Such novel methods could help the development of novel therapeutics for AD.

Severe fever with thrombocytopenia syndrome virus (SFTSV) or Dabie bandavirus is an emerging pathogen responsible for SFTS. It is considered a novel threat to human health, given the high associated fatality. SFTSV is a segmented negative-strand RNA virus containing three single-stranded RNAs, with the M segment encoding the glycoproteins Gn and Gc. Gc is vital for viral entry into the host cell surface, along with the Gn protein. As the Gc is the surface-exposable antigen from virions, it is a critical diagnostic marker of infection. Although various SFTSV Gn or N protein-based sero-diagnostic methods have been developed, there are no commercially available sero-diagnostic kits. Therefore, we generated monoclonal antibodies (mAbs) against SFTSV Gc and explored their application in serum diagnostic tests to develop sensitive serodiagnostic tools covering broad-range genotypes (A to F). First, 10 SFTSV Gc antibody-binding fragments (Fabs) were isolated using a phage display system and converted into human IgGs. Enzyme-linked immunosorbent assays (ELISA) of the SFTSV and Rift Valley fever virus (RVFV: same genus as SFTSV) Gc antigens showed that all antibodies attached to the SFTSV Gc protein had high affinity. An immunofluorescence assay (IFA), to verify the cross-reactivity of seven antibodies with high affinities for various SFTSV genotypes (A, B2, B3, D, and F) and detect mAb binding with intact Gc proteins, revealed that five IgG type mAbs were bound to intact Gc proteins of various genotypes. Six high-affinity antibodies were selected using ELISA and IFA. The binding capacity of the six antibodies against the SFTSV Gc antigen was measured using surface plasmon resonance. All antibodies had high binding capacity. Consequently, these antibodies serve as valuable markers in the serological diagnosis of SFTSV.