[Identification and expression analysis of whole gene family of Isatis indigotica 4-coumarate: CoA ligase].

The 4-coumarate: CoA ligase(4CL) is a key enzyme in the upstream pathway of phenylpropanoids such as flavonoids, soluble phenolic esters, lignans, and lignins in plants. In this study, 13 4CL family members of Arabidopsis thaliana were used as reference sequences to identify the 4CL gene family candidate members of Isatis indigotica from the reported I. indigotica genome. Further bioinformatics analysis and analysis of the expression pattern of 4CL genes and the accumulation pattern of flavonoids were carried out. Thirteen 4CL genes were obtained, named Ii4CL1-Ii4CL13, which were distributed on chromosomes 1, 2, 3, 4, and 6. The analysis of the gene structure and conserved structural domains revealed the intron number of I. indigotica 4CL genes was between 1 and 12 and the protein structural domains were highly conserved. Cis-acting element analysis showed that there were multiple response elements in the promoter sequence of I. indigotica 4CL gene family, and jasmonic acid had the largest number of reaction elements. The collinearity analysis showed that there was a close relationship between the 4CL gene family members of I. indigotica and A. thaliana. As revealed by qPCR results, the expression analysis of the 4CL gene family showed that 10 4CL genes had higher expression levels in the aboveground part of I. indigotica. The content assay of flavonoids in different parts of I. indigotica showed that flavonoids were mainly accumulated in the aboveground part of plants. This study provides a basis for further investigating the roles of the 4CL gene family involved in the biosynthesis of flavonoids in I. indigotica.

Discovery and characterization of a novel cGAS covalent inhibitor for the treatment of inflammatory bowel disease.

Cyclic GMP-AMP synthase (cGAS), a cytosolic DNA sensor, acts as a nucleotidyl transferase that catalyzes ATP and GTP to form cyclic GMP-AMP (cGAMP) and plays a critical role in innate immunity. Hyperactivation of cGAS-STING signaling contributes to hyperinflammatory responses. Therefore, cGAS is considered a promising target for the treatment of inflammatory diseases. Herein, we report the discovery and identification of several novel types of cGAS inhibitors by pyrophosphatase (PPiase)-coupled activity assays. Among these inhibitors, 1-(1-phenyl-3,4-dihydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)prop-2-yn-1-one (compound 3) displayed the highest potency and selectivity at the cellular level. Compound 3 exhibited better inhibitory activity and pathway selectivity than RU.521, which is a selective cGAS inhibitor with anti-inflammatory effects in vitro and in vivo. Thermostability analysis, nuclear magnetic resonance and isothermal titration calorimetry assays confirmed that compound 3 directly binds to the cGAS protein. Mass spectrometry and mutation analysis revealed that compound 3 covalently binds to Cys419 of cGAS. Notably, compound 3 demonstrated promising therapeutic efficacy in a dextran sulfate sodium (DSS)-induced mouse colitis model. These results collectively suggest that compound 3 will be useful for understanding the biological function of cGAS and has the potential to be further developed for inflammatory disease therapies.

[Developments in Research on the Relationship Between Porphyromonas gingivalis and Non-Oral Diseases].

Porphyromonas gingivalis ( P. gingivalis) is a common periodontal pathogen. Recently, there has been increasing evidence suggesting that P. gingivalis is not only a common pathogen in the oral cavity, but is also closely associated with non-oral diseases, including inflammatory bowel disease, cancer, cardiovascular diseases, Alzheimer's disease, rheumatoid arthritis, diabetes mellitus, premature birth and non-alcoholic hepatitis, etc. Herein, we reviewed the developments in recent years in research on the relationship between P. gingivalis, a periodontal pathogen, and non-oral diseases, which will help determine whether P. gingivalis could be used as an auxiliary diagnostic biomarker or a potential therapeutic target for these non-oral diseases, thus contributing to the development of treatment strategies for the relevant diseases.

[Cloning and catalytic analysis of Isatis indigotica chalcone isomerase in vitro].

Chalcone isomerase is a key rate-limiting enzyme in the biosynthesis of flavonoids in higher plants, which determines the production of flavonoids in plants. In this study, RNA was extracted from different parts of Isatis indigotica and reverse-transcribed into cDNA. Specific primers with enzyme restriction sites were designed, and a chalcone isomerase gene was cloned from I. indigotica, named IiCHI. IiCHI was 756 bp in length, containing a complete open reading frame and encoding 251 amino acids. Homology analysis showed that IiCHI was closely related to CHI protein of Arabidopsis thaliana and had typical active sites of chalcone isomerase. Phylogenetic tree analysis showed that IiCHI was classified into type Ⅰ CHI clade. Recombinant prokaryotic expression vector pET28a-IiCHI was constructed and purified to obtain IiCHI recombinant protein. In vitro enzymatic analysis showed that the IiCHI protein could convert naringenin chalcone into naringenin, but could not catalyze the production of liquiritigenin by isoliquiritigenin. The results of real-time quantitative polymerase chain reaction(qPCR) showed that the expression level of IiCHI in the aboveground parts was higher than that in the underground parts and the expression level was the highest in the flowers of the aboveground parts, followed by leaves and stems, and no expression was observed in the roots and rhizomes of the underground parts. This study has confirmed the function of chalcone isomerase in I. indigotica and provided references for the biosynthesis of flavonoid components.

Genetically Encoded Sensor Enables Endogenous RNA Imaging with Conformation-Switching Induced Fluorogenic Proteins.

Genetically encoded molecular tools are crucial for live cell RNA imaging, and few are available for endogenous RNA imaging. We develop a new genetically encoded sensor using conformation switching RNA induced fluorogenic proteins that enable multicolor and signal-amplified imaging of endogenous RNAs. The sensor system is designed with an RNA sensing module and a degron-fused fluorescent protein reporter. Target RNA induces conformation switching of the RNA sensing module to form RNA aptamers that stabilize the degron-fused protein for fluorogenic imaging. This sensor is demonstrated for high-contrast imaging of survivin mRNA abundance and dynamics in live cells. Moreover, the sensor system is extended to a multicolor palette by screening fluorogenic proteins of distinct colors, and engineered into a signal amplifier using the split fluorescent protein design. The sensor is further exploited for imaging lncRNA MALAT-1 and its translocation dynamics during mitosis. Our sensor system can afford a valuable platform for RNA imaging in biomedical research and clinical theranostics.

Racemization at the Asp 58 residue in αA-crystallin from the lens of high myopic cataract patients.

Post-translational modifications in lens proteins are key causal factors in cataract. As the most abundant post-translational modification in the lens, racemization may be closely related to the pathogenesis of cataract. Racemization of αA-crystallin, a crucial structural and heat shock protein in the human lens, could significantly influence its structure and function. In previous studies, elevated racemization from l-Asp 58 to d-isoAsp58 in αA-crystallin has been found in age-related cataract (ARC) lenses compared to normal aged human lenses. However, the role of racemization in high myopic cataract (HMC), which is characterized by an early onset of nuclear cataract, remains unknown. In the current study, apparently different from ARC, significantly increased racemization from l-Asp 58 to d-Asp 58 in αA-crystallin was identified in HMC lenses. The average racemization rates for each Asp isoform were calculated in ARC and HMC group. In ARC patients, the conversion of l-Asp 58 to d-isoAsp 58, up to 31.89%, accounted for the main proportion in racemization, which was in accordance with the previous studies. However, in HMC lenses, the conversion of l-Asp 58 to d-Asp 58, as high as 35.44%, accounted for the largest proportion of racemization in αA-crystallin. The different trend in the conversion of αA-crystallin by racemization, especially the elevated level of d-Asp 58 in HMC lenses, might prompt early cataractogenesis and a possible explanation of distinct phenotypes of cataract in HMC.

Siderotic cataract with no signs of intraocular foreign body.

BACKGROUND: Ocular siderosis is a clinical condition induced by deposition of an iron-containing intraocular foreign body. We report a unique case of histopathologically proven lens siderosis in a young woman with a preceding history of trauma but no signs of retained intraocular foreign body. CASE PRESENTATION: A 32-year-old woman presented with an opacified lens showing brownish deposits on the anterior capsule and underwent cataract surgery. Preoperative ophthalmic examination did not show any retained intraocular foreign body. Histopathologic staining of the anterior capsule confirmed the presence of iron deposits and macrophages. Electroretinography examination performed in the postoperative period showed the changes characteristic of retinal degeneration in ocular siderosis. CONCLUSION: This case illustrates the importance of close monitoring of patients with a history of trauma or previous penetrating injury to the eye, even if there is no intraocular foreign body, because they might develop ocular siderosis at a later stage. This case report underscores the importance of electroretinography and histopathologic analysis, in addition to ophthalmic examination, in the diagnosis of ocular siderosis.

Diagnosis of pupillary block glaucoma after removal of congenital cataracts with intraoperative ultrasound biomicroscopy: a case report.

BACKGROUND: Aphakic glaucoma is a common complication after congenital cataract extraction, especially in those who have surgery during infancy. This case report describes a case of bilateral pupillary block glaucoma diagnosed with intraoperative ultrasound biomicroscopy (UBM) after removal of congenital cataract. CASE PRESENTATION: We present a case report of a 9-month-old infant with bilateral corneal enlargement and ocular hypertension after uneventful removal of congenital cataracts. Initial and follow-up examination findings were reviewed. The infant was suspected to have developmental glaucoma and schemed to have bilateral trabeculotomy until pupillary obstruction by vitreous herniation and angle closure with iris bombé were detected by intraoperative UBM. Anterior vitrectomy and goniosynechialysis were then performed as treatment. CONCLUSION: Pupillary block glaucoma is a rare type of infantile aphakic glaucoma. Application of intraoperative UBM can assist in the differential diagnosis of aphakic glaucoma in infants.

αA-crystallin gene CpG islands hypermethylation in nuclear cataract after pars plana vitrectomy.

PURPOSE: To investigate the DNA methylation status of αA-crystallin gene in cataract secondary to pars plana vitrectomy. METHODS: Anterior capsular membranes of 40 eyes of 40 patients with cataract secondary to vitrectomy were collected. Another 20 eyes of 20 patients who received pars plana vitrectomy and phacoemulsification in the primary procedure, were recruited as control. Methylation status of the CpG islands of αA-crystallin gene was analyzed by pyrosequencing. Expression of αA-crystallin was evaluated by real-time polymerase chain reaction and western blot. RESULTS: In the post vitrectomy group, five patients with posterior subcapsular opacity and four patients with cortical opacity were excluded from further analysis. The remaining 31 patients with nuclear cataract were assigned into two groups according to tamponade types: 19 of octafluoropropane (C3F8) and 12 of silicone oil (SiO). The average nuclear color grading was elevated both in C3F8 and SiO groups after vitrectomy. Compared to the control group, hypermethylation of the CpG islands in the αA-crystallin gene promoter was found in both post vitrectomy groups, accompanied by significantly reduced αA-crystallin expression. No statistically significant differences were found between the C3F8 and SiO groups either for DNA methylation status or αA-crystallin expression. CONCLUSIONS: CpG islands hypermethylation of αA-crystallin gene may be involved in nuclear cataract formation after pars plana vitrectomy.

Identification of proteins that interact with alpha A-crystallin using a human proteome microarray.

PURPOSE: To identify proteins interacting with alpha A-crystallin (CRYAA) and to investigate the potential role that these protein interactions play in the function of CRYAA using a human proteome (HuProt) microarray. METHODS: The active full-length CRYAA protein corresponding to amino acids 1-173 of CRYAA was recombined. A HuProt microarray composed of 17,225 human full-length proteins with N-terminal glutathione S-transferase (GST) tags was used to identify protein-protein interactions. The probes were considered detectable when the signal to noise ratio (SNR) was over 1.2. The identified proteins were subjected to subsequent bioinformatics analysis using the DAVID database. RESULTS: The HuProt microarray results showed that the signals of 343 proteins were higher in the recombinant CRYAA group than in the control group. The SNR of 127 proteins was ≥ 1.2. The SNR of the following eight proteins was > 3.0: hematopoietic cell-specific Lyn substrate 1 (HCLS1), Kelch domain-containing 6 (KLHDC6), sarcoglycan delta (SGCD), KIAA1706 protein (KIAA1706), RNA guanylyltransferase and 5'-phosphatase (RNGTT), chromosome 10 open reading frame 57 (C10orf57), chromosome 9 open reading frame 52 (C9orf52), and plasminogen activator, urokinase receptor (PLAUR). The bioinformatics analysis revealed 127 proteins associated with phosphoproteins, alternative splicing, acetylation, DNA binding, the nuclear lumen, ribonucleotide binding, the cell cycle, WD40 repeats, protein transport, transcription factor activity, GTP binding, and cellular response to stress. Functional annotation clustering showed that they belong to cell cycle, organelle or nuclear lumen, protein transport, and DNA binding and repair clusters. CRYAA interacted with these proteins to maintain their solubility and decrease the accumulation of denatured target proteins. The protein-protein interactions may help CRYAA carry out multifaceted functions. CONCLUSIONS: One-hundred and twenty-seven of 17,225 human full-length proteins were identified that interact with CRYAA. The advent of microarray analysis enables a better understanding of the functions of CRYAA as a molecular chaperone.

Syntheses, characterization, and properties of Ru(II) complexes based on pi-conjugated terpyridine ligand with tetrathiafulvalene moiety.

Two ruthenium(II) complexes [Ru(TTF-terpy)(terpy)][PF(6)](2) (terpy = 2,2':6',2''-terpyridine) (1) and [Ru(TTF-terpy)(2)][PF6](2) (2) were synthesized by reactions of Ru(terpy)(dmso)(2)Cl(2) or cis-Ru(dmso)(4)Cl(2) with 4'-tetrathiafulvalene-2,2':6',2''-terpyridine (TTF-terpy), respectively. The crystal structure of 1 has been determined by X-ray crystallography. In the crystal of complex 1, molecules are seized together into 1D chains via pi···pi stacking interactions. The electrochemical and spectroscopic properties of these compounds have been studied. The results show that these Ru(II) complexes show stepwise redox processes in solution, and are promising building blocks for the construction of multi-functional materials.

Paris polyphylla ethanol extract and polyphyllin I ameliorate adenomyosis by inhibiting epithelial-mesenchymal transition.

BACKGROUND: The active ingredients of the Chinese medical herb Paris polyphylla, P. polyphylla ethanol extract (PPE) and polyphyllin I (PPI), potentially inhibit epithelial-mesenchymal transition (EMT) in tumors. However, the roles of these ingredients in inhibiting EMT in adenomyosis (AM) remain to be explored. PURPOSE: The primary goal of the study was to uncover the underlying molecular processes through which PPE and PPI suppress EMT in AM, alongside assessing the safety profiles of these substances. METHODS: To assess the suppressive impact of PPE on adenomyosis-derived cells (AMDCs), we employed Transwell and wound healing assays. The polyphyllins (PPI, PPII, PPVII) contained in PPE were characterized using high-performance liquid chromatography (HPLC). Then, bioinformatics techniques were performed to pinpoint potential PPI targets that could be effective in treating AM. Immunoblotting was used to verify the key proteins and pathways identified via bioinformatics. Furthermore, we examined the efficacy of PPE and PPI in treating Institute of Cancer Research (ICR) mice with AM by observing the morphological and pathological features of the uterus and performing immunohistochemistry. In addition, we assessed safety by evaluating liver, kidney and spleen pathologic features and serum test results. RESULTS: Three major polyphyllins of PPE were revealed by HPLC, and PPI had the highest concentration. In vitro experiments indicated that PPE and PPI effectively prevent AMDCs invasion and migration. Bioinformatics revealed that the primary targets E-cadherin, N-cadherin and TGFß1, as well as the EMT biological process, were enriched in PPI-treated AM. Immunoblotting assays corroborated the hypothesis that PPE and PPI suppress the TGFß1/Smad2/3 pathway in AMDCs to prevent EMT from progressing. Additionally, in vivo studies showed that PPE (3 mg/kg and 6 mg/kg) and PPI (3 mg/kg and 6 mg/kg), successfully suppressed the EMT process through targeting the TGFß1/Smad2/3 signaling pathway. Besides, it was observed that lower doses of PPE (3 mg/kg) and PPI (3 mg/kg) exerted minimal effects on the liver, kidneys, and spleen. CONCLUSIONS: PPE and PPI efficiently impede the development of EMT by inhibiting the TGFß1/Smad2/3 pathway, revealing an alternative pathway for the pharmacological treatment of AM.

Low Dimensional Nanostructure-Assisted Long-Range Surface Plasmon Resonance Sensors With High Figure of Merit.

Long-range surface plasmon resonance (LRSPR) sensors have been extensively studied by virtue of their extremely narrow full width at half maxima (FWHM) characteristics, but their low sensitivity remains an important factor limiting the figure of merit (FOM), making the sensors have difficulties in detecting small refractive index changes accurately. To address this problem, this paper proposes and demonstrates a low dimensional nanostructure (Au nanospheres, WS2) assisted LRSPR sensor to achieve an effective enhancement of the sensor interfaced electric field and thus improve the sensitivity. The performance parameters of the two sensors are compared with the LRSPR sensor by finite element method analysis, and the results showed that the assistance of the low dimensional nanostructure has a positive effect on the sensor. The first refractive index sensing experiment of the WS2-assisted LRSPR sensor was realized with a 25.47% increase in sensitivity and a 7.13% increase in FOM simultaneously, and the Au nanospheres-assisted LRSPR sensor with a 29.23% increase in sensitivity and a 15.95% increase in FOM simultaneously. The introduction of low dimensional nanostructures provides a flexible and effective means of sensitization for LRSPR sensors, making the plasmon resonance sensors combine high sensitivity, narrow FWHM and high FOM, which have promising applications in biochemical sensing.

Nitric oxide synthase and its function in animal reproduction: an update.

Nitric oxide (NO), a free radical labile gas, is involved in the regulation of various biological functions and physiological processes during animal reproduction. Recently, increasing evidence suggests that the biological role and chemical fate of NO is dependent on dynamic regulation of its biosynthetic enzyme, three distinct nitric oxide synthase (NOS) according to their structure, location and function. The impact of NOS isoforms on reproductive functions need to be timely elucidated. Here, we focus on and the basic background and latest studies on the development, structure, importance inhibitor, location pattern, complex functions. Moreover, we summarize the exactly mechanisms which involved some cell signal pathways in the regulation of NOS with cellular and molecular level in the animal reproduction. Therefore, this growing research area provides the new insight into the important role of NOS male and female reproduction system. It also provides the treatment evidence on targeting NOS of reproductive regulation and diseases.

Role of p63/p73 in epithelial remodeling and their response to steroid treatment in nasal polyposis.

BACKGROUND: Nasal polyposis (NP) is recognized as aberrant epithelial remodeling, but the molecular mechanism underlying this process is poorly understood. Two important p53 homologues (p63 and p73) play a key role in orchestrating the epithelial development. OBJECTIVE: We intended to study whether p63 and p73 are involved in the epithelial remodeling seen in patients with NP and their response to oral glucocorticosteroid (GC) treatment. METHODS: Nasal polyp tissues were obtained from 65 patients, and inferior turbinates were obtained from 19 control subjects without NP. Among patients with NP, 20 were treated with oral prednisone, so that 2 sets of polyp biopsy specimens were taken before (GC naive) and after (GC treated) treatment. Immunohistochemistry and quantitative PCR were performed to determine the expression levels of p63 and p73. RESULTS: The increase in p63-positive cell numbers was significant in GC-naive NP epithelium (46%) compared with that seen in control epithelium (5%), and it was positively related to the epithelial hyperplasia in patients with NP. The increase in N-terminal transactivation domain p73-positive cell numbers was found in 27% of GC-naive patients with NP and 16% of control subjects, with no statistical difference. The mRNA expression of both p63 and p73 was significantly upregulated in GC-naive patients with NP versus control subjects, and a positive correlation between the p63 and p73 mRNAs was found in all nasal tissues. Furthermore, the improvement of epithelial structure and reduction of p63 mRNA/protein levels were found in patients with NP after GC treatment. CONCLUSIONS: Our results suggest that the ectopic expression of p63 in multiple cell layers is an important pathologic phenomenon in the epithelial remodeling seen in chronically inflamed airway epithelium (eg, in patients with NP), and its aberrant expression can be suppressed with GC treatment.

catena-Poly[[(2-amino-1,3-benzothia-zole-6-carboxyl-ato-κ(2)O,O')(2,2'-bipyridyl-κ(2)N,N')cadmium]-µ-2-amino-1,3-benzothia-zole-6-carboxyl-ato-κ(3)N(1):O,O'].

In the title coordination polymer, [Cd(C(8)H(5)N(2)O(2)S)(2)(C(10)H(8)N(2))](n), the Cd(II) ion is coordinated by a bidentate 2,2-bipyridyl ligand, two O,O'-chelating 2-amino-1,3-benzothia-zole-6-carboxyl-ate (ABTC) ligands and one N-bonded ABTC ligand. The resulting CdN(3)O(4) coordination polyhedron approximates to a very distorted penta-gonal bipramid with one O and one N atom in axial positions. One of the ABTC ligands is bridging to an adjacent metal atom, generating an infinite chain propagating in [100]. A three-dimensional network is constructed from N-H⋯O and N-H⋯N hydrogen bonds and aromatic π-π stacking inter-actions [centroid-centroid separations = 3.641 (2) and 3.682 (3) Å].

[Pollution Characteristics and Influencing Factors of PM2.5 in Shanxi Province Based on Wavelet Transform].

Based on the daily average concentration of PM2.5, social influencing factor data, and meteorological data of 11 cities in Shanxi Province from 2015 to 2019, the concentration period of PM2.5 was determined using wavelet transform. The correlation between PM2.5 and social influencing factors and meteorological factors was explored respectively through Spearman correlation and the wavelet coherence spectrum, and the main influencing factors of long-term and short-term management and control of PM2.5 were determined. The results showed that the concentration of PM2.5 in Shanxi Province showed an upward trend from 2015 to 2017, with an average annual increase rate of 4.3% and a downward trend from 2018 to 2019, with an average annual decrease rate of 4.2%. The average concentration of PM2.5 showed a "U" distribution, with the highest value in January (95 µg·m-3) and the lowest in August (34 µg·m-3); the average value in winter was approximately twice that in summer. The ρ(PM2.5) in southern cities such as Linfen was 62 µg·m-3, and the average value in Datong and other northern cities was 45 µg·m-3, which was high in the south and low in the north. There were significant periodic changes in PM2.5 concentration in the 11 cities, including a long period of approximately 293 d and a short period of approximately 27 d. Among them, the energy consumption level and industrial structure were the strong driving factors affecting the PM2.5 concentration in the long period of Shanxi Province. In the short period, it was greatly affected by the change in atmospheric circulation, and different cities were affected by typical meteorological factors. Linfen, Yuncheng, Datong, Shuozhou, and Xinzhou were vulnerable to wind speed; Jinzhong and Luliang were vulnerable to temperature; and Taiyuan, Jincheng, Yangquan, and Changzhi were uniquely and significantly affected by relative humidity. Therefore, industrial structure adjustment and energy structure adjustment are key to the long-term control of atmospheric PM2.5 and the long-term improvement of air quality in Shanxi Province. The differential impact of different urban meteorological factors on PM2.5 should be considered when carrying out short-term regional joint prevention and control.

Research advances on surface plasmon resonance biosensors.

The surface plasmon resonance (SPR) phenomenon is of wide interest due to its sensitivity to changes in surface refractive index for the label-free, highly sensitive and rapid detection of biomarkers. This paper reviews research progress on SPR biosensors modified with different substrate structures and surface materials, surface plasmon resonance imaging (SPRI), and SPR-enhanced electrochemiluminescent (ECL) biosensors for applications in biosensing in the last five years. This paper focuses on the research on the application of the SPR phenomenon in the field of bio-detection, reviews the sensing characteristics of SPR biosensors with substrate structures of prisms, gratings, and optical fibers, and summarizes and analyzes the sensitivity and interference resistance of SPR sensors with surface modification of different materials (high-refractive index dielectric films, metallic micro- and nanostructures, and surface antifouling materials). Considering that imaging is an important tool for biomedical detection, this paper reviews the research progress on SPRI technology in the field of biomedical detection. In addition, this paper also reviews the research progress on SPR-enhanced ECL biosensors in the field of biosensing. Finally, this paper provides an outlook on the development trends of biosensing technology in terms of portable high-precision SPR sensors, reduction of self-loss of thin film materials, optimization of image processing techniques and simplification of electrode modification for ECL sensors.

Sulfated alginate oligosaccharide exerts antitumor activity and autophagy induction by inactivating MEK1/ERK/mTOR signaling in a KSR1-dependent manner in osteosarcoma.

Alginate oligosaccharide (AOS) has the function to inhibit tumor progression and the sulfated modification can enhance the antitumor activity. To date, the function and mechanism of sulfated AOS (AOS-SO4) in tumors remain largely elusive. We prepared AOS by the enzymatic degradation of alginate, collected AOS-SO4 by sulfating following the canonical procedure. Using these materials, in vitro assays showed that both AOS and AOS-SO4 elicited antitumor effects in osteosarcoma cells. Sulfated modification significantly enhanced the antitumor activity. In addition, AOS-SO4 had obvious effects on cell cycle arrest, apoptosis, and autophagy induction in vitro and in vivo. Mechanistically, we observed that AOS-SO4 treatment triggered proapoptotic autophagy by inhibiting MEK1/ERK/mTOR signaling. The ERK activator reversed AOS-SO4-induced autophagy. More importantly, we found that KSR1 interacted with MEK1 and functioned as a positive regulator of MEK1 protein in osteosarcoma cells. High KSR1 expression was significantly associated with poor survival in osteosarcoma patients. Together, these results suggest that AOS-SO4 has a better antitumor effect in osteosarcoma by inhibiting MEK1/ERK/mTOR signaling, which is KSR1-dependent; thus, AOS-SO4 can be a new potential therapeutic candidate for the treatment of osteosarcoma.

Racemization in cataractous lens from diabetic and aging individuals: analysis of Asp 58 residue in αA-crystallin.

Cataract is the leading cause of visual impairment globally. Racemization of lens proteins may contribute to cataract formation in aging individuals. As a special type of age-related cataract (ARC), diabetic cataract (DC) is characterized by the early onset of cortical opacification and finally developed into a mixed type of cortical and nuclear opacification. We compared racemization of Asp 58 residue, a hotspot position in αA-crystallin, from the cortex and nucleus of diabetic and age-matched senile cataractous lenses, by identifying L-Asp/L-isoAsp/D-Asp/D-isoAsp by mass spectrometry. Compared to nondiabetic cataractous lenses, DC lenses showed a significantly increased cortex/nucleus ratio of D-Asp 58, which originated primarily from an increased percentage of D-Asp 58 in the lens cortex of DC. Moreover, patients diagnosed with diabetes for over 10 years showed a lower cortex/nucleus ratio of D-isoAsp 58 in the lens compared with those who had a shorter duration of diabetes, which originated mainly from an increased percentage of D-isoAsp 58 in the lens nucleus of DC with increasing time of hyperglycemia. Further analysis confirmed decreased protein solubility in diabetic cataractous lenses. The different racemization pattern in DC may be distinguished from ARC and influence its phenotype over the protracted duration of diabetes.