• Preparation, purification, and identification of novel antioxidant peptides derived from Gracilariopsis lemaneiformis protein hydrolysates

      Hu, Xiao; Liu, Jing; Li, Jun; Song, Yuqiong; Chen, Shengjun; Zhou, Shaobo; Yang, Xianqing; ; Chinese Academy of Fishery Sciences; Jiangsu Ocean University; et al. (Frontiers, 2022-07-22)
      Gracilariopsis lemaneiformis (G. lemaneiformis) protein was hydrolyzed with alkaline protease to obtain antioxidant peptides. The enzymatic hydrolysis conditions were optimized through single-factor and orthogonal experiments. The results showed that the optimal process parameters were using 2% of alkaline protease, and substrate concentration of 1 g/100 mL and hydrolyzed 2 h at pH 8.0. Gel filtration chromatography and RP-HPLC were adopted for isolating and purifying the antioxidant peptides from the G. lemaneiformis protein hydrolysate (GLPH). Three novel antioxidant peptides were identified as LSPGEL (614.68 Da), VYFDR (698.76 Da), and PGPTY (533.57 Da) by nano-HPLC-MS/MS. The results of ABTS free radical scavenging rate demonstrated PGPTY exhibited the best antioxidant activity (IC50 = 0.24 mg/mL). Moreover, LSPGEL, VYFDR, and PGPTY were docked with Keap1, respectively. The molecular docking results suggested PGPTY had smaller docking energy and inhibition constants than the other two peptides. Finally, the cell viability assay evidenced the protective effect exerted by the antioxidant peptide on H2O2-induced oxidative damage. Above findings showed the potential of using antioxidant peptides from GLPH as antioxidants.
    • NRF2-ARE signaling is responsive to haloacetonitrile-induced oxidative stress in human keratinocytes

      Xue, Peng; Wang, Huihui; Yang, Lili; Jiang, Zhiqiang; Li, Hongliang; Liu, Qinxin; Zhang, Qiang; Andersen, Melvin E.; Crabbe, M. James C.; Hao, Lipeng; et al. (Elsevier, 2022-07-14)
      Humans are exposed to disinfection by-products through oral, inhalation, and dermal routes, during bathing and swimming, potentially causing skin lesions, asthma, and bladder cancer. Nuclear factor E2-related factor 2 (NRF2) is a master regulator of the adaptive antioxidant response via the antioxidant reaction elements (ARE) orchestrating the transcription of a large group of antioxidant and detoxification genes. Here we used an immortalized human keratinocyte model HaCaT cells to investigate NRF2-ARE as a responder and protector in the acute cytotoxicity of seven haloacetonitriles (HANs), including chloroacetonitrile (CAN), bromoacetonitrile (BAN), iodoacetonitrile (IAN), bromochloroacetonitrile (BCAN), dichloroacetonitrile (DCAN), dibromoacetonitrile (DBAN), and trichloroacetonitrile (TCAN) found in drinking water and swimming pools. The rank order of cytotoxicity among the HANs tested was IAN ≈ BAN ˃ DBAN ˃ BCAN ˃ CAN ˃ TCAN ˃ DCAN based on their LC50. The HANs induced intracellular reactive oxygen species accumulation and activated cellular antioxidant responses in concentration- and time-dependent fashions, showing elevated NRF2 protein levels and ARE activity, induction of antioxidant genes, and increased glutathione levels. Additionally, knockdown of NRF2 by lentiviral shRNAs sensitized the HaCaT cells to HANs-induced cytotoxicity, emphasizing a protective role of NRF2 against the cytotoxicity of HANs. These results indicate that HANs cause oxidative stress and activate NRF2-ARE-mediated antioxidant response, which in turn protects the cells from HANs-induced cytotoxicity, highlighting that NRF2-ARE activity could be a sensitive indicator to identify and characterize the oxidative stress induced by HANs and other environmental pollutants.
    • Comparative genomic and phylogenetic analysis of chloroplast genomes of hawthorn (Crataegus spp.) in southwest China

      Wu, Xien; Luo, Dengli; Zhang, Yingmin; Yang, Congwei; Crabbe, M. James C.; Zhang, Ti-Cao; Li, Guodong; Yunnan University of Chinese Medicine; Oxford University; University of Bedfordshire; et al. (Frontiers, 2022-07-04)
      The hawthorns (Crataegus spp.) are widely distributed and famous for their edible and medicinal values. There are ~18 species and seven varieties of hawthorn in China distributed throughout the country. We now report the chloroplast genome sequences from C. scabrifolia, C. chungtienensis and C. oresbia, from the southwest of China and compare them with the previously released six species in Crataegus and four species in Rosaceae. The chloroplast genome structure of Crataegus is typical and can be divided into four parts. The genome sizes are between 159,654 and 159,898bp. The three newly sequenced chloroplast genomes encode 132 genes, including 85 protein-coding genes, 37 tRNA genes, and eight rRNA genes. Comparative analysis of the chloroplast genomes revealed six divergent hotspot regions, including ndhA, rps16-trnQ-UUG, ndhF-rpl32, rps16-psbK, trnR-UCU-atpA and rpl32-trnL-UAG. According to the correlation and cooccurrence analysis of repeats with indels and SNPs, the relationship between them cannot be ignored. The phylogenetic tree constructed based on the complete chloroplast genome and intergenic region sequences indicated that C. scabrifolia has a different origin from C. chungtienensis and C. oresbia. We support the placement of C. hupehensis, C. cuneata, C. scabrifolia in C. subg. Crataegus and C. kansuensis, C. oresbia, C. kansuensis in C. subg. Sanguineae. In addition, based on the morphology, geographic distribution and phylogenetic relationships of C. chungtienensis and C. oresbia, we speculate that these two species may be the same species. In conclusion, this study has enriched the chloroplast genome resources of Crataegus and provided valuable information for the phylogeny and species identification of this genus.
    • Statistical learning-based spatial downscaling models for precipitation distribution

      Wu, Yichen; Zhang, Zhihua; Crabbe, M. James C.; Das, Lipon Chandra (Hindawi, 2022-06-07)
      The downscaling technique produces high spatial resolution precipitation distribution in order to analyze impacts of climate change in data-scarce regions or local scales. In this study, based on three statistical learning algorithms, such as support vector machine (SVM), random forest regression (RF), and gradient boosting regressor (GBR), we proposed an effcient downscaling approach to produce high spatial resolution precipitation. In order to demonstrate effciency and accuracy of our models over traditional multilinear regression (MLR) downscaling models, we did a downscaling analysis for daily observed precipitation data from 34 monitoring sites in Bangladesh. Validation revealed that R2 of GBR could reach 0.98, compared with RF (0.94), SVM (0.88), and multilinear regression (MLR) (0.69) models, so the GBR-based downscaling model had the best performance among all four downscaling models. We suggest that the GBR-based downscaling models should be used to replace traditional MLR downscaling models to produce a more accurate map of high-resolution precipitation for flood disaster management, drought forecasting, and long-term planning of land and water resources.
    • An insight into the impact of thermal process on dissolution profile and physical characteristics of theophylline tablets made through 3D printing compared to conventional methods

      Nashed, Nour; Lam, Matthew; Ghafourian, Taravat; Pausas, Lluis; Jiri, Memory; Majumder, Mridul; Nokhodchi, Ali; University of Sussex; University of Bedfordshire; M2M Pharmaceuticals Ltd (MDPI, 2022-06-06)
      The dissolution profile is of great importance in drug delivery and is affected by the manufacturing method. Thus, it is important to study the influence of the thermal process on drug release in emerging technologies such as 3D printing-fused deposition modeling (FDM). For this purpose, the characteristics of 3D printed tablets were compared to those of tablets prepared by other thermal methods such as hot-melt extrusion (HME) and non-thermal methods such as physical mixture (PM). Theophylline was used as a drug model and blends of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) were used as a matrix former. The solid state of the drug in all formulations was investigated by differential scanning calorimetry, X-ray powder diffraction, and Fourier-transformed infrared spectroscopy. All studied tablets had the same weight and surface area/volume (SA/V). Dissolution data showed that, for some formulations, printed tablets interestingly had a faster release profile despite having the highest hardness values (>550 N) compared to HME and PM tablets. Porosity investigations showed that 100% infill printed tablets had the highest porosity (~20%) compared to HME (<10%) and PM tablets (≤11%). True density records were the lowest in printed tablets (~1.22 g/m3) compared to tablets made from both HME and PM methods (~1.26 g/m3), reflecting the possible increase in polymer specific volume while printing. This increase in the volume of polymer network may accelerate water and drug diffusion from/within the matrix. Thus, it is a misconception that the 3D printing process will always retard drug release based on increased tablet hardness. Hardness, porosity, density, solid-state of the drug, SA/V, weight, and formulation components are all factors contributing to the release profile where the total balance can either slow down or accelerate the release profile.
    • Genomic insights into recent species divergence in Nicotiana benthamiana and natural variation in Rdr1 gene controlling viral susceptibility.

      Cauz-Santos, Luiz A.; Dodsworth, Steven; Samuel, Rosabelle; Christenhusz, Maarten J.M.; Patel, Denise; Shittu, Taiwo Adewale; Jakob, Aljaž; Paun, Ovidiu; Chase, Mark W.; ; et al. (Wiley, 2022-05-10)
      One of the most commonly encountered and frequently cited laboratory organisms worldwide is classified taxonomically as Nicotiana benthamiana (Solanaceae), an accession of which, typically referred to as LAB, is renowned for its unique susceptibility to a wide range of plant viruses and hence capacity to be transformed using a variety of methods. This susceptibility is the result of an insertion and consequent loss of function in the RNA dependent RNA polymerase 1 (Rdr1) gene. However, the origin and age of LAB and evolution of N. benthamiana across its wide distribution in Australia remains relatively underexplored. Here, we have used multispecies coalescent methods on genome-wide single nuclear polymorphisms (SNPs) to assess species limits, phylogenetic relationships and divergence times within N. benthamiana. Our results show that the previous taxonomic concept of this species in fact comprises five geographically, morphologically and genetically distinct species, one of which includes LAB. We provide clear evidence that LAB is closely related to accessions collected further north in the Northern Territory; this species split much earlier, c. 1.1 million years ago, from their common ancestor than the other four in this clade and is morphologically the most distinctive. We also found that the Rdr1 gene insertion is variable among accessions from the northern portions of the Northern Territory. Furthermore, this long-isolated species typically grows in sheltered sites in subtropical/tropical monsoon areas of northern Australia, contradicting the previously advanced hypothesis that this species is an extremophile that has traded viral resistance for precocious development.
    • ER stress in COVID-19 and Parkinson's Disease: in vitro and in silico evidences

      Chaudhry, Zahara Latif; Gamal, Mahmoud; Ferhati, Ingrid; Warda, Mohamad; Ahmed, Bushra Y.; ; University of Bedfordshire; Cairo University (MDPI, 2022-04-16)
      The outbreak of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) signifies a serious worldwide concern to public health. Both transcriptome and proteome of SARS-CoV-2-infected cells synergize the progression of infection in host, which may exacerbate symptoms and/or progression of other chronic diseases such as Parkinson's disease (PD). Oxidative stress is a well-known cause of endoplasmic reticulum (ER) stress observed in both SARS-CoV-2 and PD. In the current study, we aimed to explore the influence of PKR-like ER kinase (PERK) stress pathway under SARS-CoV-2-mediated infection and in human cell model of PD. Furthermore, we investigated whether they are interconnected and if the ER stress inhibitors could inhibit cell death and provide cellular protection. To achieve this aim, we have incorporated in silico analysis obtained from gene set enrichment analysis (GSEA), a literature review and laboratory data. The neurotoxin, 6-hydroxy dopamine (6OHDA), was used to mimic the biochemical and neuropathological characteristics of PD by inducing oxidative stress in dopamine-containing neurons differentiated from ReNVM cell line (dDCNs). Furthermore, we explored if ER stress influences activation of caspases-2, -4 and -8 in SARS-CoV-2 and in stressed dDCNs. Our laboratory data using Western blot, immunocytochemistry and 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) analyses indicated that 6OHDA-induced toxicity triggered activation of caspases-2, -4 and -8 in dDCNs. Under SARS-CoV-2 infection of different cell types, GSEA revealed cell-specific sensitivities to oxidative and ER stresses. Cardiomyocytes and type II alveolar epithelial-like cells were more vulnerable to oxidative stress than neural cells. On the other side, only cardiomyocytes activated the unfolded protein response, however, the PERK pathway was operative in both cardiomyocytes and neural cells. In addition, caspase-4 activation by a SARS-CoV-2 was observed via in silico analyses. These results demonstrate that the ER stress pathway under oxidative stress in SARS-CoV-2 and PD are interconnected using diverse pathways. Furthermore, our results using the ER stress inhibitor and caspase specific inhibitors provided cellular protection suggesting that the use of specific inhibitors can provide effective therapeutic approaches for the treatment of COVID-19 and PD.
    • Prospective association of dietary soy and fibre intake with puberty timing: a cohort study among Chinese children

      Xiong, Jingyuan; Xu, Yujie; Liu, Xueting; Wang, Xiaoyu; Shan, Shufang; Crabbe, M. James C.; Zhao, Li; Fang, He; Cheng, Guo; ; et al. (BMC, 2022-04-04)
      Background: Dietary phytoestrogens have been suggested to influence puberty timing, a critical stage for wellbeing in adulthood. We hypothesized that childhood soy intake might prospectively influence puberty timing and that dietary fibre and the key isoflavone metabolite equol might play roles. Methods: Cox proportional hazard regression models were performed in 4781 children (2152 girls and 2629 boys) aged 6–8 years old from the Chinese Adolescent Cohort Study for whom a food frequency questionnaire at baseline and information about potential confounders were available. Anthropometry and pubertal status including age at Tanner stage 2 for breast development (B2) or age at the initiation of gonadal growth (G2), and age at menarche (M) or voice break (VB) were assessed annually. Equol excretion was determined by urine samples from 1311 participants. Results: Among girls and boys, higher soy intake was associated with later puberty timing (hazard ratio (HR)-B2: 0.88 (95% CI, 0.80–0.96), p=0.02; HR-M, 0.87 (0.77–0.94), p=0.01; HR-G2, 0.91 (0.82–0.98), p=0.013; HR-VB, 0.90 (0.82–0.9), p=0.02), independent of prepubertal body fatness and fibre intake. These associations were more pronounced among children with a high urinary equol level (pfor-interaction ≤ 0.04) or with a high cereal fibre intake (pfor-interaction ≤ 0.06). Intake of dietary fibre or its subtype was not prospectively associated with puberty onset after adjusting for dietary soy intake (p≥0.06). Conclusion: Higher childhood soy intake is prospectively associated with later puberty timing in both Chinese girls and boys, independent of prepubertal body fatness, and the association is particularly pronounced among individuals with a higher urinary equol level.
    • Study on the association of dietary fatty acids intake and serum lipid profiles with cognition in aging subjects with type 2 diabetes mellitus

      Li, Pengfei; Gao, Yanyan; Ma, Xiaojun; Zhou, Shaobo; Guo, Yujie; Xu, Jingjing; Wang, Xixiang; Van Halm-Lutterodt, Nicholas; Yuan, Linhong; Capital Medical University, Beijing; et al. (Frontiers, 2022-03-31)
      Background: The correlation between dietary fatty acid (FA) intake and serum lipid profile levels with cognition in the aged population has been reported by previous studies. However, the association of dietary FA intake and serum lipid profile levels with cognition in subjects with type 2 diabetes mellitus (T2DM) is seldom reported. Objective: A cross-sectional study was conducted to explore the correlation between dietary FA intake and serum lipid profiles with cognition in the aged Chinese population with T2DM. Methods: A total of 1,526 aged Chinese subjects were recruited from communities. Fasting blood samples were collected for parameter measurement. The food frequency questionnaire (FFQ) method was applied for a dietary survey. Cognition was assessed using the Montreal Cognitive Assessment (MoCA) test. Dietary FA intake and serum lipid levels were compared between subjects with T2DM and control subjects. A logistic regression analysis was carried out for analyzing the association of FA intake and serum lipid levels with the risk of mild cognitive impairment (MCI) in subjects with T2DM and control subjects. Results: There was a significant difference in the serum lipid level between the T2DM group and the control group. Results of the logistic regression analysis demonstrated the potential associations of serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), and dietary n-3 polyunsaturated fatty acids (PUFAs) intake with the risk of MCI in subjects with T2DM, but the associations were not observed in control subjects. Conclusion: The T2DM phenotype might affect the relationship between dietary FA intake, circulating lipids, and cognitive performance. Large prospective cohort studies are needed to uncover the underlying mechanism of how dietary FA intake and serum lipid levels affect cognition in aged subjects with T2DM.
    • Spatial-temporal distribution, cancer risk, and disease burden attributed to the dietary dioxins exposure of Chinese residents

      Zheng, Weiwei; Zhao, Huijuan; Crabbe, M. James C.; Qu, Weidong; Fudan University; Oxford University; University of Bedfordshire (Elsevier, 2022-03-26)
      This study analyzed the characteristics of dioxins represented by polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as well as dioxin-like polychlorinated biphenyls (dl-PCBs) in food from China. The spatial-temporal distribution characteristics of dioxins dietary intake, cancer risk, and disease burden were evaluated among the Chinese population. In the temporal dimension, descending trends in animal-origin-food were found both in dietary intake PCDD/Fs and dl-PCBs, with the reverse for plant-origin-food. The probability assessments of dietary intakes showed that after 2007, the exposure level of PCDD/Fs through diets of urban and rural residents in China was significantly lower than that before 2007 (p &lt; 0.05). The spatial distribution results showed that the southern coastal regions were high exposure regions of dietary intakes of PCDD/Fs and dl-PCBs. Cancer risk and disease burden of dietary dioxins showed downward trends after 2007 both under an average exposure scenario and an extreme exposure scenario. After 2007, the disease burden resulting from exposure to dl-PCBs became higher and approached the median of values reported by the WHO, while the disease burden resulting from exposure to PCDD/Fs approached the lower level of 95% CI reported by the WHO. The results indicate that accompanying the National Implementation Plan and a series of subsequent scientific guidance documents launched for reducing dioxins pollution in 2007, the health benefits and the health risks caused by dl-PCBs should be given further attention and evaluation in future studies.
    • Effects and mechanism of Ganoderma lucidum polysaccharides in the treatment of diabetic nephropathy in streptozotocin-induced diabetic rats

      Hu, Yu; Wang, Shu-Xiang; Wu, Fu-Yu; Wu, Ke-Jia; Shi, Rui-Ping; Qin, Li-Hong; Lu, Chun-Feng; Wang, Shu-Qiu; Wang, Fang-Fang; Zhou, Shaobo; et al. (Hindawi, 2022-03-08)
      Ganoderma lucidum polysaccharides (GLP) have renal protection effect but there was no study on the diabetic nephropathy. This study was designed to investigate its effect and mechanism using a diabetic rat model induced by streptozotocin (50 mg/kg, i.p.). The diabetic rats were treated with GLP (300 mg/kg/day) for 10 weeks. The blood glucose, glycated hemoglobin, body weight, and the levels of blood creatinine, urea nitrogen, and urine protein were assessed. And renal pathologies were assessed by the tissue sections stained with hematoxylin-eosin, Masson’s trichome, and periodic acid-Schiff. The expression of phosphorylated phosphoinositide 3 kinase (p-PI3K), phosphorylated protein kinase B (p-Akt), and phosphorylated mammalian target of rapamycin (p-mTOR), the autophagy proteins beclin-1, LC3-II, LC3-I, and P62; the apoptosis-related proteins caspase-3 and caspase-9; and the inflammation markers IL-6, IL-1β, and TNF-ɑ were assessed. Results showed that GLP alleviated the impairment of renal function by reducing urinary protein excretion and the blood creatinine level and ameliorated diabetic nephropathy. The expression of p-PI3K, p-Akt, and p-mTOR in the diabetic kidney were significantly reduced in the GLP treatment group compared to the without treatment group. GLP treatment activated the autophagy indicators of beclin-1 and the ratio of LC3-II/LC3-I but reduced p62 and also inhibited the expression of caspase-3, caspase-9 and IL-6, IL-1β, and TNF-ɑ. In conclusion, the effect of GLP amelioration diabetic nephropathy may be via the PI3k/Akt/mTOR signaling pathway by inhibition of the apoptosis and inflammation and activation of the autophagy process.
    • Multi-level analysis and identification of tumor mutational burden genes across cancer types

      Wang, Shuangkuai; Tong, Yuantao; Zong, Hui; Xu, Xuewen; Crabbe, M. James C.; Wang, Ying; Zhang, Xiaoyen; Tongji University; Oxford University; Second Military Medical University; et al. (MDPI, 2022-02-17)
      Tumor mutational burden (TMB) is considered a potential biomarker for predicting the response and effect of immune checkpoint inhibitors (ICIs). However, there are still inconsistent standards of gene panels using next-generation sequencing and poor correlation between the TMB genes, immune cell infiltrating, and prognosis. We applied text-mining technology to construct specific TMB-associated gene panels cross various cancer types. As a case exploration, Pearson’s correlation between TMB genes and immune cell infiltrating was further analyzed in colorectal cancer. We then performed LASSO Cox regression to construct a prognosis predictive model and calculated the risk score of each sample for receiver operating characteristic (ROC) analysis. The results showed that the assessment of TMB gene panels performed well with fewer than 500 genes, highly mutated genes, and the inclusion of synonymous mutations and immune regulatory and drug-target genes. Moreover, the analysis of TMB differentially expressed genes (DEGs) suggested that JAKMIP1 was strongly correlated with the gene expression level of CD8+ T cell markers in colorectal cancer. Additionally, the prognosis predictive model based on 19 TMB DEGs reached AUCs of 0.836, 0.818, and 0.787 in 1-, 3-, and 5-year OS models, respectively (C-index: 0.810). In summary, the gene panel performed well and TMB DEGs showed great potential value in immune cell infiltration and in predicting survival.
    • Single enrichment systems possibly underestimate both exposures and biological effects of organic pollutants from drinking water

      Yang, Lan; Zhou, Ying; Chen, Li; Chen, Hanyi; Liu, Wenhao; Zheng, Weiwei; Andersen, Melvin E.; Zhang, Yubing; Hu, Yi; Crabbe, M. James C.; et al. (Elsevier, 2022-01-03)
      Comprehensive enrichment of contaminants in drinking water is an essential step for accurately determining exposure levels of contaminants and testing their biological effects. Traditional methods using a single absorbent for enriching contaminants in water might not be adequate for complicated matrices with different physical-chemical profiles . To examine this hypothesis, we used an integrated enrichment system that had three sequential stages-XAD-2 resin, poly (styrene–divinylbenzene) and activated charcoal to capture organic pollutants and disinfection by-products (DBPs) from drinking water in Shanghai. Un-adsorbed Organic Compounds in Eluates (UOCEs) named UOCEs-A, -B, and-C following each adsorption stage were determined by gas chromatography-mass spectromet ry to evaluate adsorption efficiency of the enrichment system . Meanwhile, biological effects such as cytotoxicity, effects on reactive oxygen species (ROS) generation and glutathione (GSH) depletion were determined in human LO2 cells to identify potential adverse effects on exposure to low dose contaminants. We found that poly-styrene–divinylbenzene (PS-DVB) and activated charcoal (AC) could still partly collect UOCEs-A and-B that the upper adsorption column incompletely captured, and that potential carcinogens like 2- naphthamine were present in all eluates. UOCEs-A at (1-4000), UOCEs-B at (1000-4000), and UOCEs-C at (2400-4000) folds of the actual concentrations had significant cytotoxicity to LO2 cells. Additionally, ROS and GSH change in cells treated with UOCEs indicated the potential for long-term effects of exposure to some mixtures of contaminants such as DBPs at low doses . These results suggested that an enriching system with a single adsorbent would underestimate the exposure level of pollutants and the biological effects of organic pollutants from drinking water. Effective methods for pollutants’ enrichment and capture of drinking water should be given priority in future studies on accurate evaluation of biological effects exposed to mixed pollutants via drinking water.
    • Solubility study of acetylsalicylic acid in ethanol + water mixtures: measurement, mathematical modeling, and stability discussion

      Nokhodchi, Ali; Ghafourian, Taravat; Nashed, Nour; Asare-Addo, Kofi; Behboudi, Elmira; Sefid-Sefidehkhan, Yasaman; Zarghampour, Aynaz; Rahimpour, Elaheh; Jouyban, Abolghasem; (Springer Science and Business Media Deutschland GmbH, 2021-12-28)
      Solubility determination of poorly water-soluble drugs is pivotal for formulation scientists when they want to develop a liquid formulation. Performing such a test with different ratios of cosolvents with water is time-consuming and costly. The scarcity of solubility data for poorly water-soluble drugs increases the importance of developing correlation and prediction equations for these mixtures. Therefore, the aim of the current research is to determine the solubility of acetylsalicylic acid in binary mixtures of ethanol+water at 25 and 37°C. Acetylsalicylic acid is non-stable in aqueous solutions and readily hydrolyze to salicylic acid. So, the solubility of acetylsalicylic acid is measured in ethanolic mixtures by HPLC to follow the concentration of produced salicylic acid as well. Moreover, the solubility of acetylsalicylic acid is modeled using different cosolvency equations. The measured solubility data were also predicted using PC-SAFT EOS model. DSC results ruled out any changes in the polymorphic form of acetylsalicylic acid after the solubility test, whereas XRPD results showed some changes in crystallinity of the precipitated acetylsalicylic acid after the solubility test. Fitting the solubility data to the different cosolvency models showed that the mean relative deviation percentage for the Jouyban-Acree model was less than 10.0% showing that this equation is able to obtain accurate solubility data for acetylsalicylic acid in mixtures of ethanol and water. Also, the predicted data with an average mean relative deviation percentage (MRD%) of less than 29.65% show the capability of the PC-SAFT model for predicting solubility data. A brief comparison of the solubilities of structurally related solutes to acetylsalicylic acid was also provided.
    • Optimized degradation and inhibition of α-glucosidase activity by gracilaria lemaneiformis polysaccharide and its production in vitro

      Long, Xiaoshan; Hu, Xiao; Zhou, Shaobo; Xiang, Huan; Chen, Shengjun; Li, Laihao; Liu, Shucheng; Yang, Xianqing; Chinese Academy of Fishery Sciences; Jiangsu Ocean University; et al. (MDPI, 2021-12-22)
      Gracilaria lemaneiformis polysaccharide (GLP) exhibits good physiological activities, and it is more beneficial as it is degraded. After its degradation by hydrogen peroxide combined with vitamin C (H2 O2-Vc) and optimized by Box–Behnken Design (BBD), a new product of GLP-HV will be generated. While using GLP as control, two products of GLP-H (H2 O2-treated) and GLP-V (Vc-treated) were also produced. These products chemical characteristics (total sugar content, molecular weight, monosaccharide composition, UV spectrum, morphological structure, and hypolipidemic activity in vitro) were assessed. The results showed that the optimal conditions for H2 O2-Vc degradation were as follows: H2 O2-Vc concentration was 18.7 mM, reaction time was 0.5 h, and reaction temperature was 56◦ C. The total sugar content of GLP and its degradation products (GLP-HV, GLP-H and GLP-V) were more than 97%, and their monosaccharides are mainly glucose and galactose. The SEM analysis demonstrated that H2 O2-Vc made the structure loose and broken. Moreover, GLP, GLP-HV, GLP-H, and GLP-V had significantly inhibition effect on α-glucosidase, and their IC50 value were 3.957, 0.265, 1.651, and 1.923 mg/mL, respectively. GLP-HV had the best inhibition effect on α-glucosidase in a dose-dependent manner, which was the mixed type of competitive and non-competitive. It had a certain quenching effect on fluorescence of α-glucosidase, which may be dynamic quenching.
    • AU-rich element RNA binding proteins: at the crossroads of post-transcriptional regulation and genome integrity

      Sidali, Ahmed; Teotia, Varsha; Solaiman, Nadeen Shaikh; Bashir, Nahida; Kanagaraj, Radhakrishnan; Murphy, John J.; Surendranath, Kalpana; University of Westminster; University of Bedfordshire (MDPI, 2021-12-22)
      Genome integrity must be tightly preserved to ensure cellular survival and to deter the genesis of disease. Endogenous and exogenous stressors that impose threats to genomic stability through DNA damage are counteracted by a tightly regulated DNA damage response (DDR). RNA binding proteins (RBPs) are emerging as regulators and mediators of diverse biological processes. Specifically, RBPs that bind to adenine uridine (AU)-rich elements (AREs) in the 3′ untranslated region (UTR) of mRNAs (AU-RBPs) have emerged as key players in regulating the DDR and preserving genome integrity. Here we review eight established AU-RBPs (AUF1, HuR, KHSRP, TIA-1, TIAR, ZFP36, ZFP36L1, ZFP36L2) and their ability to maintain genome integrity through various interactions. We have reviewed canonical roles of AU-RBPs in regulating the fate of mRNA transcripts encoding DDR genes at multiple post-transcriptional levels. We have also attempted to shed light on non-canonical roles of AU-RBPs exploring their post-translational modifications (PTMs) and sub-cellular localization in response to genotoxic stresses by various factors involved in DDR and genome maintenance. Dysfunctional AU-RBPs have been increasingly found to be associated with many human cancers. Further understanding of the roles of AU-RBPS in maintaining genomic integrity may uncover novel therapeutic strategies for cancer. View Full-Text
    • Dynamic changes of DNA methylation during wild strawberry (Fragaria nilgerrensis) tissue culture

      Cao, Qiang; Feng, Yuxi; Dai, Xiongwei; Huang, Lin; Li, Jiamin; Tao, Pang; Crabbe, M. James C.; Zhang, Ti-Cao; Qiao, Qin; Yunnan University; et al. (Frontiers, 2021-11-30)
      Tissue culture is an important tool for asexual propagation and genetic transformation of strawberry plants. In plant tissue culture, variation of DNA methylation is a potential source of phenotypic variation in regenerated plants. However, the genome wide dynamic methylation patterns of strawberry tissue culture remain unclear. In this study, we used whole-genome bisulfite sequencing (WGBS) to study genomic DNA methylation changes of a wild strawberry Fragaria nilgerrensis at six stages: from explants of shoot tips to outplanting and acclimation. Global methylation levels showed that CG sites exhibited the highest methylation level in all stages with an average of 49.5%, followed by CHG (33.2%) and CHH (12.4%). Although CHH accounted for the lowest proportion of total cytosine methylation, it showed the most obvious methylation change and the most of these changes occurred in the transposable element regions. The overall methylation levels alternately decreased and increased during the entire tissue culture process and the distribution of DNA methylation was non-uniform among different genetic regions. Furthermore, much more differentially methylated regions (DMRs) were detected in dedifferentiation and redifferentiation stages and most of them were transposable elements, suggesting these processes involved activating or silencing of amounts of transposons. The functional enrichment of the DMR-related genes indicated that genes involved in hormone metabolic processes, plant development and the stress response changed methylation throughout the tissue culture process. Finally, the quantitative real-time PCR (qRT-PCR) was conducted to examine the association of methylation and gene expression of a set of different methylated genes. Our findings give deeper insight into the epigenetic regulation of gene expression during the plant tissue cultures process, which will be useful in the efficient control of somaclonal variations and in crop improvement.
    • Identification of diverse lipid-binding modes in the groove of zinc α2 glycoprotein reveals its functional versatility

      Zahid, Henna; Lau, Andy M.; Kelly, Sharon M.; Karu, Kersti; Gor, Jayesh; Perkins, Stephen J.; McDermott, Lindsay C. (Wiley, 2021-11-24)
      ZAG is a multifunctional glycoprotein with a class I MHC-like protein fold and an α1-α2 lipid-binding groove. The intrinsic ZAG ligand is unknown. Our previous studies showed that ZAG binds the dansylated C11 fatty acid, DAUDA, differently to the boron dipyrromethane C16 fatty acid, C16-BODIPY. Here, the molecular basis for this difference was elucidated. Multi-wavelength analytical ultracentrifugation confirmed that DAUDA and C16-BODIPY individually bind to ZAG and compete for the same binding site. Molecular docking of lipid-binding in the structurally related CD1-proteins predicted nine conserved ligand contact residues in ZAG. Twelve mutants were accordingly created by alanine scanning site directed mutagenesis for characterisation. Mutation of Y12 caused ZAG to misfold. Mutation of K147, R157 and A158 abrogated C16-BODIPY but not DAUDA binding. L69 and T169 increased the fluorescence emission intensity of C16-BODIPY but not of DAUDA compared to wild-type ZAG and showed that C16-BODIPY binds close to T169 and L69. Distance measurements of the crystal structure revealed K147 forms a salt bridge with D83. A range of bioactive bulky lipids including phospholipids and sphingolipids displaced DAUDA from the ZAG binding site but unexpectedly did not displace C16-BODIPY. We conclude that the ZAG α1-α2 groove contains separate but overlapping sites for DAUDA and C16-BODIPY and is involved in binding to a bulkier and wider repertoire of lipids than previously reported. This work suggested that the in vivo activity of ZAG may be dictated by its lipid ligand.
    • Regulation of cell cycle and differentiation markers by pathogenic, non-pathogenic and opportunistic skin bacteria

      Younis, Sidra; Deeba, Farah; Fatima Saeed, Rida; Mothana, Ramzi A.; Ullah, Riaz; Faheem, Muhammad; Javed, Qamar; Blumenberg, Miroslav; National University of Medical Sciences, Pakistan; Quaid-e-Azam University; et al. (Elsevier B.V., 2021-11-02)
      Skin is the first line of defense against the physical, chemical and the biological environment. It is an ideal organ for studying molecular responses to biological infections through a variety of skin cells that specialize in immune responses. Comparative analysis of skin response to pathogenic, non-pathogenic, and commensal bacteria would help in the identification of disease specific pathways for drug targets. In this study, we investigated human breast reduction skin responses to Cutibacterium acnes (C. acnes), Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and TLR1/2 agonist using Affymetrix microarray chips. The Pam3CSK4 solution and bacterial cultures were prepared and inoculated in steel rings, that were placed on the acetone treated epidermis in a petri dish. After 24 h incubation, 8 mm punch biopsies were taken from the center of the ring, and RNA was extracted. The genome-wide expression was then analyzed using Affymetrix HG-133A gene chip microarray. We found that the C. acnes and S. aureus boosted the production of extracellular matrix components and attenuated the expression of differentiation markers. The above responses were mediated through the TLR2 pathway. Skin also responded to S. aureus and C. acnes by inducing the genes of the cell cycle machinery; this response was not TLR2-dependent. S. aureus induced, whereas C. acnes suppressed the genes associated with apoptosis; this was also not TLR2-dependent. Moreover, S. epidermis apparently did not lead to changes in gene expression. We conclude that the breast reduction skin is a very useful model to study the global gene expression in response to bacterial treatments.
    • Nance-Horan Syndrome-like 1 protein negatively regulates Scar/WAVE-Arp2/3 activity and inhibits lamellipodia stability and cell migration

      Law, Ah-Lai; Jalal, Shamsinar; Pallett, Tommy; Mosis, Fuad; Guni, Ahmad; Brayford, Simon; Yolland, Lawrence; Marcotti, Stefania; Levitt, James A.; Poland, Simon P.; et al. (Nature Research, 2021-09-28)
      Cell migration is important for development and its aberrant regulation contributes to many diseases. The Scar/WAVE complex is essential for Arp2/3 mediated lamellipodia formation during mesenchymal cell migration and several coinciding signals activate it. However, so far, no direct negative regulators are known. Here we identify Nance-Horan Syndrome-like 1 protein (NHSL1) as a direct binding partner of the Scar/WAVE complex, which co-localise at protruding lamellipodia. This interaction is mediated by the Abi SH3 domain and two binding sites in NHSL1. Furthermore, active Rac binds to NHSL1 at two regions that mediate leading edge targeting of NHSL1. Surprisingly, NHSL1 inhibits cell migration through its interaction with the Scar/WAVE complex. Mechanistically, NHSL1 may reduce cell migration efficiency by impeding Arp2/3 activity, as measured in cells using a Arp2/3 FRET-FLIM biosensor, resulting in reduced F-actin density of lamellipodia, and consequently impairing the stability of lamellipodia protrusions.