Gallic Acid Improves Comorbid Chronic Pain and Depression Behaviors by Inhibiting P2X7 Receptor-Mediated Ferroptosis in the Spinal Cord of Rats.

Ferroptosis is an inflammatory programmed cell death process that is dependent on iron deposition and lipid peroxidation. The P2X7 receptor not only is involved in the pain process but also is closely related to the onset of depression. Gallic acid (3,4,5-trihydroxybenzoic acid), which is naturally found in a variety of plants, exhibits anti-inflammatory, antioxidant, and analgesic effects. This study established a rat model with the comorbidity of chronic constrictive injury (CCI) plus chronic unpredictable mild stress (CUMS) to explore the role and mechanism of gallic acid in the treatment of pain and depression comorbidity. Our experimental results showed that pain and depression-like behaviors were more obvious in the chronic constriction injury (CCI) plus chronic unpredictable mild stimulation (CUMS) group than they were in the sham operation group, and the P2X7-reactive oxygen species (ROS) signaling pathway was activated. The tissue iron concentration was increased, and mitochondrial damage was observed in the CCI plus CUMS group. These results were alleviated with gallic acid treatment. Therefore, we speculate that gallic acid inhibits the ferroptosis of the spinal microglia by regulating the P2X7-ROS signaling pathway and relieves the behavioral changes in rats with comorbid pain and depression.

Application Effect of Transparent Supervision Based on Informatization in Prevention and Control of Carbapenem-Resistant Klebsiella pneumoniae Nosocomial Infection.

Objective: To explore the effect of transparent supervision model on the prevention and control of carbapenem-resistant Klebsiella pneumoniae (CRKP) nosocomial infection and the value of the autoregressive integrated moving average (ARIMA) model in predicting the incidence of CRKP infection. Methods: A total of 46,873 inpatients from Jiawang District People's Hospital of Xuzhou between January 2019 and December 2019 (prior to COVID-19 prevention and control) were selected as the preintervention group and 45,217 inpatients from January 2020 to December 2020 (after the COVID-19 prevention and control) as the postintervention group. We performed transparent supervision on CRKP patients detected by the real-time monitoring system for nosocomial infection. Incidence and detection rate of CRKP, utilization rate of special grade hydrocarbon enzyme alkene antibiotics, hand hygiene compliance rate, qualified rate of ATP tests on surface of environmental objects, and execution rate of CRKP core prevention and control were compared between the two groups. Results: Transparent supervision of CRKP-infected patients was conducted daily from January to December 2020, which resulted in the following: (a) the infection rate of CRKP decreased in a fluctuating manner, and the actual value of hydrocarbon alkene use rate was basically the same as the predicted value with an overall decreasing trend; (b) after the intervention, hand hygiene compliance rate increased from 53.30% to 70.24% (P < 0.001) and the ATP qualified rate increased from 53.77% to 92.24% (P < 0.001); (c) the fitted value of the ARIMA model was in good agreement with the actual value. The incidence of CRKP infection and the utilization rate of carbene antibiotics were also in good agreement with the predicted value. The average relative errors were 11% and 10.78%. Conclusions: During the COVID-19 outbreak in 2020, the ARIMA model effectively fit and predicted the CRKP infection rate, thereby providing scientific guidance for the prevention and control of CRKP infection. In addition, the transparent supervision intervention model improved the hand hygiene compliance and environmental hygiene qualification rates of medical staff, effectively reducing CRKP cross-infection in the hospital.

A mutated glycosaminoglycan-binding domain functions as a novel probe to selectively target heparin-like epitopes on tumor cells.

The high heterogeneity and mutation rate of cancer cells often lead to the failure of targeted therapy, and therefore, new targets for multitarget therapy of tumors are urgently needed. Aberrantly expressed glycosaminoglycans (GAGs) have been shown to be involved in tumorigenesis and are promising new targets. Recently, the GAG-binding domain rVAR2 of the Plasmodium falciparum VAR2CSA protein was identified as a probe targeting cancer-associated chondroitin sulfate A-like epitopes. In this study, we found that rVAR2 could also bind to heparin (Hep) and chondroitin sulfate E. Therefore, we used rVAR2 as a model to establish a method based on random mutagenesis of the GAG-binding protein and phage display to identify and optimize probes targeting tumor GAGs. We identified a new probe, VAR2HP, which selectively recognized Hep by interacting with unique epitopes consisting of a decasaccharide structure that contains at least three HexA2S(1-4)GlcNS6S disaccharides. Moreover, we found that these Hep-like epitopes were overexpressed in various cancer cells. Most importantly, our in vivo experiments showed that VAR2HP had good biocompatibility and preferentially localizes to tumors, which indicates that VAR2HP has great application potential in tumor diagnosis and targeted therapy. In conclusion, this study provides a strategy for the discovery of novel tumor-associated GAG epitopes and their specific probes.

Beneficial Effects of lncRNA-UC.360+ shRNA on Diabetic Cardiac Sympathetic Damage via NLRP3 Inflammasome-Induced Pyroptosis in Stellate Ganglion.

Hyperglycemia is one of the common symptoms of diabetes, and it produces excessive reactive oxygen species (ROS). This study investigated whether the long noncoding RNA (lncRNA) UC.360+ is involved in diabetic cardiac autonomic neuropathy (DCAN) mediated by NLRP3 inflammasome-induced pyroptosis in the stellate ganglion (SG). Using a rat type 2 diabetes model, we found that lncRNA UC.360+ short hairpin RNA (shRNA) ameliorated the dyslipidaemia of type 2 diabetic rats and reduced serum adrenaline and ROS production in SG under hyperglycemia. In addition, UC.360+ shRNA also reduced the expression of nuclear factor kappa-B (NF-κB), NLRP3, ASC, caspase-1, interleukin-1ß (IL-1ß), and IL-18 in the SG of diabetic rats and inhibited the phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK). Therefore, lncRNA-UC.360+ shRNA may modulate the NLRP3 inflammasome/inflammatory pathway in the SG, which in turn alleviates diabetic heart sympathetic nerve damage.

Corrigendum: Long Non-coding RNA Uc.48+ Small Interfering RNA Alleviates Neuroinflammatory Hyperalgesia in Gp120-Treated Rats via the P2Y12 Receptor.

[This corrects the article DOI: 10.3389/fnins.2021.663962.].

Long Non-coding RNA Uc.48+ Small Interfering RNA Alleviates Neuroinflammatory Hyperalgesia in Gp120-Treated Rats via the P2Y12 Receptor.

Human immunodeficiency virus envelope glycoprotein 120 (gp120) leads to hyperalgesia. Long non-coding RNAs are characterized by the lack of a protein-coding sequence and may contribute to the development and maintenance of inflammatory and neuroinflammatory pain. Rats with neuroinflammatory pain were established by gp120 treatment, which is featured by intensified pain behaviors. Long non-coding RNA uc.48+ was increased in the dorsal root ganglia of gp120-treated rats, and small interfering RNA that targets uc.48+ markedly alleviated hyperalgesia in gp120-treated rats. Notably, uc.48+ overexpression increased P2Y12 expression in control rats dorsal root ganglia and induced hyperalgesia. Uc.48+ small interfering RNA inhibited P2Y12 expression in gp120-treated rats. Uc.48+ potentiated P2Y12 receptor functions in the neurons and heterologous cells. Therefore, uc.48+ siRNA treatment reduced the upregulation of P2Y12 expression and function in DRG neurons, and, hence, alleviated hyperalgesia in gp120-treated rats.

A Technical System for the Large-Scale Application of Metabolites From Paecilomyces variotii SJ1 in Agriculture.

Compared with endophytes, metabolites from endophytes (MEs) have great potential in agriculture. However, a technique for industrializing the production of MEs is still scarce. Moreover, the establishment of effective methods for evaluating the quality of MEs is hampered by the fact that some compounds with beneficial effects on crops have not been clearly identified. Herein, a system was established for the production, quality control and application of MEs by using the extract from Paecilomyces variotii SJ1 (ZNC). First, the extraction conditions of ZNC were optimized through response surface methodology, after which each batch (500 L) met the consumption requirements of crops in 7,467 hectares. Then, chromatographic fingerprinting and enzyme-linked immunosorbent assay were applied to evaluate the similarity and specificity of unknown effective components in ZNC, ensuring a similarity of more than 90% and a quantitative accuracy of greater than 99.9% for the products from different batches. Finally, the bioactivity of industrially produced ZNC was evaluated in the field, and it significantly increased the potato yields by 4.4-10.8%. Overall, we have established a practical technical system for the large-scale application of ZNC in agriculture.

Rolling the WSSe Bilayer into Double-Walled Nanotube for the Enhanced Photocatalytic Water-Splitting Performance.

For the emerging Janus transition metal dichalcogenides (TMD) layered water-splitting photocatalysts, stacking the monolayers to form bilayers has been predicted to be an effective way to improve their photocatalytic performances. To achieve this, the stacking pattern plays an important role. In this work, by means of the density functional theory calculations, we comprehensively estimate energetical stability, light absorption and redox capacity of Janus WSSe bilayer with different stacking patterns. Unfortunately, the Janus WSSe bilayer with the most stable configuration recover the out-of-plane symmetry, which is not in favor of the photocatalytic reactions. However, rolling the Janus WSSe bilayer into double-walled nanotube could stabilize the appropriate stacking pattern with an enhanced instinct dipole moment. Moreover, the suitable band edge positions, high visible light absorbance, outstanding solar-to-hydrogen efficiency (up to 28.48%), and superior carrier separation promise the Janus WSSe double-walled nanotube the potential for the photocatalytic water-splitting application. Our studies not only predict an ideal water-splitting photocatalyst, but also propose an effective way to improve the photocatalytic performances of Janus layered materials.

LncRNA UC.360+ shRNA Improves Diabetic Cardiac Sympathetic Dysfunction Mediated by the P2X4 Receptor in the Stellate Ganglion.

Diabetic cardiac autonomic neuropathy (DCAN) is a complication that affects more than 60% of diabetic patients. There is evidence for the involvement of P2X4 receptor in DCAN. This study showed that the expression of the long noncoding RNA (lncRNA) UC.360+ was increased in the stellate ganglion (SG) of type 2 diabetes mellitus (DM) rats, and in situ hybridization revealed a clear presence of UC.360+ in SG neurons. The potential roles of UC.360+ in DCAN and its relationship with P2X4 receptor in SG were further explored via application of the short hairpin RNA (shRNA) against lncRNA UC.360+ in DM rats. The abnormal cardiac sympathetic changes in diabetic rats were improved after treatment with lncRNA UC.360+ shRNA. In the SG of these shRNA-treated DM rats, the upregulation of P2X4, tumor necrosis factor-α (TNF-α), interleukin 1ß (IL-1ß), and phosphorylated ERK1/2 was inhibited. Thus, lncRNA UC.360+ shRNA treatment may improve DCAN mediated by the P2X4 receptor in SG.

Tacrolimus 0.03% ointment treatment in exfoliative cheilitis: A randomised controlled clinical trial and monitoring blood concentration.

BACKGROUND: Tacrolimus has been used to treat various inflammatory skin diseases, but its safety for topical application on the oral mucosa is unknown. Exfoliative cheilitis (EC) is a chronic inflammatory disorder of the lips characterised by repeated scaling; it is difficult to manage. The aim of this study was to assess the efficacy and safety of tacrolimus 0.03% ointment as a topical treatment in patients with EC. METHODS: In this randomised controlled clinical trial, 40 patients with EC were randomly assigned to receive either tacrolimus 0.03% ointment (experimental group, n = 20) or triamcinolone acetonide 0.1% cream (control group, n = 20) treatment for a 3-week period. Medication was administered in 3, 2 and 1 daily doses during the first, second and third weeks, respectively. The patients with complete healing were followed up for 3 months. The clinical outcomes were measured, including the scores regarding signs (scale, dryness, rhagades and swelling) and symptoms (rough, dry, pain, pruritus and burning sensation) at every visit. Blood concentrations of tacrolimus were assessed. RESULTS: After the 3-week treatment, healing rates of scale in the experimental and control groups were 65% and 10%, respectively (P = .018). Improvement in all signs and two symptoms (rough, pruritus) was much greater in the experimental group (P < .05). The 3-month recurrence rate was higher in the control group (P = .029). Tacrolimus blood concentrations were in the safe range (< 5 ng/mL). CONCLUSION: Topical tacrolimus 0.03% ointment has good short-term efficacy and safety for treating EC.

Investigation of action pattern of a novel chondroitin sulfate/dermatan sulfate 4-O-endosulfatase.

Recently, a novel CS/DS 4-O-endosulfatase was identified from a marine bacterium and its catalytic mechanism was investigated further (Wang, W., et. al (2015) J. Biol. Chem.290, 7823-7832; Wang, S., et. al (2019) Front. Microbiol.10, 1309). In the study herein, we provide new insight about the structural characteristics of the substrate which determine the activity of this enzyme. The substrate specificities of the 4-O-endosulfatase were probed by using libraries of structure-defined CS/DS oligosaccharides issued from synthetic and enzymatic sources. We found that this 4-O-endosulfatase effectively remove the 4-O-sulfate of disaccharide sequences GlcUAß1-3GalNAc(4S) or GlcUAß1-3GalNAc(4S,6S) in all tested hexasaccharides. The sulfated GalNac residue is resistant to the enzyme when adjacent uronic residues are sulfated as shown by the lack of enzymatic desulfation of GlcUAß1-3GalNAc(4S) connected to a disaccharide GlcUA(2S)ß1-3GalNAc(6S) in an octasaccharide. The 3-O-sulfation of GlcUA was also shown to hinder the action of this enzyme. The 4-O-endosulfatase exhibited an oriented action from the reducing to the non-reducing whatever the saturation or not of the non-reducing end. Finally, the activity of the 4-O-endosulfatase decreases with the increase in substrate size. With the deeper understanding of this novel 4-O-endosulfatase, such chondroitin sulfate (CS)/dermatan sulfate (DS) sulfatase is a useful tool for exploring the structure-function relationship of CS/DS.

Assembling custom side chains on proteoglycans to interrogate their function in living cells.

Proteoglycans (PGs) are composed of a core protein and one or more chains of glycosaminoglycans (GAGs). The highly heterogeneous GAG chains play an irreplaceable role in the functions of PGs. However, the lack of an approach to control the exact structure of GAG chains conjugated to PGs tremendously hinders functional studies of PGs. Herein, by using glypican-3 as a model, we establish an aldehyde tag-based approach to assemble PGs with specific GAG chains on the surface of living cells. We show that the engineered glypican-3 can regulate Wnt and Hedgehog signaling like the wild type. Furthermore, we also present a method for studying the interaction of PGs with their target glycoproteins by combining the assembly of PGs carrying specific GAG chains with metabolic glycan labeling, and most importantly, we obtain evidence of GPC3 directly interacting with Frizzled. In conclusion, this study provides a very useful platform for structural and functional studies of PGs with specific GAG chains.

Research and Application of Chondroitin Sulfate/Dermatan Sulfate-Degrading Enzymes.

Chondroitin sulfate (CS) and dermatan sulfate (DS) are widely distributed on the cell surface and in the extracellular matrix in the form of proteoglycan, where they participate in various biological processes. The diverse functions of CS/DS can be mainly attributed to their high structural variability. However, their structural complexity creates a big challenge for structural and functional studies of CS/DS. CS/DS-degrading enzymes with different specific activities are irreplaceable tools that could be used to solve this problem. Depending on the site of action, CS/DS-degrading enzymes can be classified as glycosidic bond-cleaving enzymes and sulfatases from animals and microorganisms. As discussed in this review, a few of the identified enzymes, particularly those from bacteria, have wildly applied to the basic studies and applications of CS/DS, such as disaccharide composition analysis, the preparation of bioactive oligosaccharides, oligosaccharide sequencing, and potential medical application, but these do not fulfill all of the needs in terms of the structural complexity of CS/DS.

Abnormal sympathetic activity after myocardial ischemia involving P2X4 in dorsal root ganglia.

The satellite glial cells (SGCs) of the dorsal root ganglia (DRG) expressed P2X4 receptor. In this study, we investigated the abnormal sympathetic activity after myocardial ischemia (MI) involving P2X4 receptor in the cervical DRG SGC. The results showed that MI injury upregulated the P2X4 receptor mRNA and protein in DRG, and the upregulated P2X4 receptor was co-localized with glial fibrillary acidic protein (GFAP) in DRG SGCs. P2X4 short hairpin RNA (shRNA) treatment decreased the expression of P2X4 receptor, counteracted the upregulation of GFAP and IL-1ß and inhibited P38MAPK phosphorylation in DRG of MI rats. These results indicate that application of P2X4 shRNA may reduce P2X4-mediated nociceptive signal via inhibiting DRG afferents to alleviate the abnormal sympathetic activity induced by MI.

Role of hesperidin in P2X3 receptor-mediated neuropathic pain in the dorsal root ganglia.

Aim: This study investigated whether the neuronal P2X3 receptor in rat dorsal root ganglia (DRG) mediated the effects of hesperidin on neuropathic pain. Materials and methods: The chronic constriction injury (CCI) model was used as a model of neuropathic pain. The mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured. The mRNA and protein expression levels were assayed by real-time RT-PCR and Western blotting. Results: The results showed that mechanical and thermal hyperalgesia in the CCI rats were increased as compared to those in the sham group. The expression levels of P2X3 mRNA and protein in CCI rats were higher than those in the sham group. Dual-labelling immunofluorescence showed that the elevated P2X3 receptor was co-expressed with the neuronal marker NeuN in the DRG of CCI rats. Hesperidin treatment decreased both the mechanical and thermal hyperalgesia, and upregulated P2X3 expression in the CCI rats. Hesperidin treatment also reduced the ERK1/2 phosphorylation in the DRG of CCI rats. Moreover, hesperidin inhibited the P2X3 agonist ATP-induced currents in HEK293 cells transfected with the P2X3 plasmid. Therefore, hesperidin treatment could reverse the elevated expression of neuronal P2X3 receptor and reduce the activation of ERK1/2 in the DRG of CCI rats. Conclusions: Our findings suggested that hesperidin inhibited the nociceptive transmission mediated by the P2X3 receptor in neurons of DRG, and thus, relieved the mechanical and thermal hyperalgesia in CCI rats.

The Inhibition by Guanfu Base A of Neuropathic Pain Mediated by P2Y12 Receptor in Dorsal Root Ganglia.

Activation of satellite glial cells (SGCs) in the dorsal root ganglia (DRG) is involved in mechanical and thermal hyperalgesia. The upregulated P2Y12 receptor expressed in SGCs of the DRG participates in the nociceptive transmission of neuropathic pain. Guanfu base A (GFA) has been reported to exhibit antiarrhythmic and anti-inflammatory effects. In this study, we explored the effects of GFA on P2Y12 receptor-mediated mechanical and thermal hyperalgesia in chronic constriction injury (CCI) rats. Sprague-Dawley rats were randomly divided into sham operation group (Sham), CCI operation group (CCI), CCI rats treated with guanfu base A group (CCI + GFA) and control rats treated with GFA group (Ctrl + GFA). Mechanical withdrawal threshold and thermal withdrawal latency were measured. P2Y12 expression in L4-L6 dorsal root ganglion (DRG) was detected by quantitative real-time PCR and Western blot. After CCI treatment, mechanical and thermal hyperalgesia and the expression values of P2Y12 receptor mRNA and protein in DRG were increased. Dual-labeling immunofluorescence showed that the coexpression of P2Y12 receptor and glial fibrillary acidic protein (GFAP) in the DRG of CCI rats was increased compared to sham rats. GFA relieved mechanical and thermal hyperalgesia in the CCI rats, decreased the expression of P2Y12 mRNA and protein and phosphorylation of p38 MAPK in the DRG, and increased the ADP-downregulated cAMP concentrations in HEK293 cells transfected with P2Y12 plasmid. After CCI rats were treated with GFA, the coexpression of P2Y12 receptor and GFAP in the DRG was significantly decreased compared to the untreated CCI group. Thus, downregulating the P2Y12 receptor relieved mechanical and thermal hyperalgesia in the CCI rats.

Quercetin relieved diabetic neuropathic pain by inhibiting upregulated P2X4 receptor in dorsal root ganglia.

The upregulation of nociceptive ion channels expressed in dorsal root ganglia (DRG) contributes to the development and retaining of diabetic pain symptoms. The flavonoid quercetin (3,3',4',5,7-pentahydroxyflavone) is a component extracted from various fruits and vegetables and exerts anti-inflammatory, analgesic, anticarcinogenic, antiulcer, and antihypertensive effects. However, the exact mechanism underlying quercetin's analgesic action remains poorly understood. The aim of this study was to investigate the effects of quercetin on diabetic neuropathic pain related to the P2X4 receptor in the DRG of type 2 diabetic rat model. Our data showed that both mechanical withdrawal threshold and thermal withdrawal latency in diabetic rats treated with quercetin were higher compared with those in untreated diabetic rats. The expression levels of P2X4 messenger RNA and protein in the DRG of diabetic rats were increased compared with the control rats, while quercetin treatment significantly inhibited such enhanced P2X4 expression in diabetic rats. The satellite glial cells (SGCs) enwrap the neuronal soma in the DRG. Quercetin treatment also lowered the elevated coexpression of P2X4 and glial fibrillary acidic protein (a marker of SGCs) and decreased the upregulation of phosphorylated p38 mitogen-activated protein kinase (p38MAPK) in the DRG of diabetic rats. Quercetin significantly reduced the P2X4 agonist adenosine triphosphate-activated currents in HEK293 cells transfected with P2X4 receptors. Thus, our data demonstrate that quercetin may decrease the upregulation of the P2X4 receptor in DRG SGCs, and consequently inhibit P2X4 receptor-mediated p38MAPK activation to relieve the mechanical and thermal hyperalgesia in diabetic rats.

Evodiamine Attenuates P2X7-Mediated Inflammatory Injury of Human Umbilical Vein Endothelial Cells Exposed to High Free Fatty Acids.

Insulin resistance and type 2 diabetes mellitus (T2DM) are highly prevalent around the world. Elevated concentrations of free fatty acids (FFAs) are closely related to insulin resistance and T2DM. P2X7 receptor is an ion channel gated by ATP, which is implicated in various scenarios including immune response, pain, and inflammation. In this study, we have explored whether P2X7 receptor is involved in pathological changes in human umbilical vein endothelial cells (HUVECs) induced by high FFA treatment, and the potential beneficial effects of evodiamine. Evodiamine could effectively suppress the enhanced expression of P2X7 receptor caused by high FFAs at both mRNA and protein levels. In addition, high FFA-induced cytotoxicity, the upregulated release of ATP, and production of reactive oxygen species (ROS) could be ameliorated by evodiamine in HUVECs. Evodiamine could also reverse the decreased NO formation and the increased adhesive events of immune cells at high FFAs. Moreover, evodiamine inhibited P2X7-dependent TNF-α expression and ERK 1/2 phosphorylation due to high FFAs. All these results indicated that evodiamine could correct the upregulated expression of P2X7 receptor induced under high FFA condition in HUVECs, and consequently suppressed oxidative stress and inflammatory responses.

Osthole alleviated diabetic neuropathic pain mediated by the P2X4 receptor in dorsal root ganglia.

Diabetes mellitus (DM) is considered the primary cause of neuropathic pain. Osthole (7-methoxy-8[3-methylpent 2-enyl]coumarin) is a component extracted from Cnidium monnieri (L.) cusson plant seeds and has anti-inflammatory and anti-oxidative properties. The aim of the present study was to investigate the effects of osthole on diabetic neuropathic pain (DNP) involving the P2X4 receptor on satellite glial cells (SGCs) in the dorsal root ganglia (DRG) of type 2 diabetic rats. These data showed that the mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) in DM rats were lower than those in control rats. MWT and TWL in DM rats treated with osthole were higher compared with those in untreated DM rats. The expression levels of P2X4 mRNA and protein in the DRG of DM rats were higher compared with those in the control rats, while those in DM rats treated with osthole were significantly lower compared with those in the untreated DM rats. Osthole treatment decreased the co-expression levels of P2X4 and glial fibrillary acidic protein (GFAP) and reduced the up-regulated expression of interleukin-1 beta (IL-1ß), tumour necrosis factor-α (TNF-α), brain-derived neurotrophic factor (BDNF) and phosphorylated-p38MAPK and enhanced the down-regulation of IL-10 in DM rats. Thus, osthole treatment may act on the P2X4 receptor to alleviate the mechanical and thermal hyperalgesia in DM rats.