Wogonin alleviates liver injury in sepsis through Nrf2-mediated NF-κB signalling suppression

Sepsis is a life‐threatening organ dysfunction syndrome, and liver is a susceptible target organ in sepsis, because the activation of inflammatory pathways contributes to septic liver injury. Oxidative stress has been documented to participate in septic liver injury, because it not only directly induces oxidative genotoxicity, but also exacerbates inflammatory pathways to potentiate damage of liver. Therefore, to ameliorate oxidative stress is promising for protecting liver in sepsis. Wogonin is the compound extracted from the medicinal plant Scutellaria baicalensis Geogi and was found to exert therapeutic effects in multiple inflammatory diseases via alleviation of oxidative stress. However, whether wogonin is able to mitigate septic liver injury remains unknown. Herein, we firstly proved that wogonin treatment could improve survival of mice with lipopolysaccharide (LPS)‐ or caecal ligation and puncture (CLP)‐induced sepsis, together with restoration of reduced body temperature and respiratory rate, and suppression of several pro‐inflammatory cytokines in circulation. Then, we found that wogonin effectively alleviated liver injury via potentiation of the anti‐oxidative capacity. To be specific, wogonin activated Nrf2 thereby promoting expressions of anti‐oxidative enzymes including NQO‐1, GST, HO‐1, SOD1 and SOD2 in hepatocytes. Moreover, wogonin‐induced Nrf2 activation could suppress NF‐κB‐regulated up‐regulation of pro‐inflammatory cytokines. Ultimately, we provided in vivo evidence that wogonin activated Nrf2 signalling, potentiated anti‐oxidative enzymes and inhibited NF‐κB‐regulated pro‐inflammatory signalling. Taken together, this study demonstrates that wogonin can be the potential therapeutic agent for alleviating liver injury in sepsis by simultaneously ameliorating oxidative stress and inflammatory response through the activation of Nrf2.

Melatonin induces the rejuvenation of long-term ex vivo expanded periodontal ligament stem cells by modulating the autophagic process

Background

Stem cells that have undergone long-term ex vivo expansion are most likely functionally compromised (namely cellular senescence) in terms of their stem cell properties and therapeutic potential. Due to its ability to attenuate cellular senescence, melatonin (MLT) has been proposed as an adjuvant in long-term cell expansion protocols, but the mechanism underlying MLT-induced cell rejuvenation remains largely unknown.

Methods

Human periodontal ligament stem cells (PDLSCs) were isolated and cultured ex vivo for up to 15 passages, and cells from passages 2, 7, and 15 (P2, P7, and P15) were used to investigate cellular senescence and autophagy change in response to long-term expansion and indeed the following MLT treatment. Next, we examined whether MLT could induce cell rejuvenation by restoring the autophagic processes of damaged cells and explored the underlying signaling pathways. In this context, cellular senescence was indicated by senescence-associated β-galactosidase (SA-β-gal) activity and by the expression of senescence-related proteins, including p53, p21, p16, and γ-H2AX. In parallel, cell autophagic processes were evaluated by examining autophagic vesicles (by transmission electronic microscopy), autophagic flux (by assessing mRFP-GFP-LC3-transfected cells), and autophagy-associated proteins (by Western blot assay of Atg7, Beclin-1, LC3-II, and p62).

Results

We found that long-term in vitro passaging led to cell senescence along with impaired autophagy. As expected, MLT supplementation not only restored cells to a younger state but also restored autophagy in senescent cells. Additionally, we demonstrated that autophagy inhibitors could block MLT-induced cell rejuvenation. When the underlying signaling pathways involved were investigated, we found that the MLT receptor (MT) mediated MLT-related autophagy restoration by regulating the PI3K/AKT/mTOR signaling pathway.

Conclusions

The present study suggests that MLT may attenuate long-term expansion-caused cellular senescence by restoring autophagy, most likely via the PI3K/AKT/mTOR signaling pathway in an MT-dependent manner. This is the first report identifying the involvement of MT-dependent PI3K/AKT/mTOR signaling in MLT-induced autophagy alteration, indicating a potential of autophagy-restoring agents such as MLT to be used in the development of optimized clinical-scale cell production protocols.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02322-9.

Exosomes derived from P2X7 receptor gene-modified cells rescue inflammation-compromised periodontal ligament stem cells from dysfunction

Although cellular therapy has been proposed for inflammation‐related disorders such as periodontitis for decades, clinical application has been unsuccessful. One explanation for these disappointing results is that the functions of stem cells are substantially compromised when they are transplanted into an inflammatory in vivo milieu. Considering the previous finding that P2X7 receptor (P2X7R) gene modification is able to reverse inflammation‐mediated impairment of periodontal ligament stem cells (PDLSCs), we further hypothesized that cells subjected to P2X7R gene transduction also exert influences on other cells within an in vivo milieu via an exosome‐mediated paracrine mechanism. To define the paracrine ability of P2X7R gene‐modified cells, P2X7R gene‐modified stem cell‐derived conditional medium (CM‐Ad‐P2X7) and exosomes (Exs‐Ad‐P2X7) were used to incubate PDLSCs. In an inflammatory osteogenic microenvironment, inflammation‐mediated changes in PDLSCs were substantially reduced, as shown by quantitative real‐time PCR (qRT‐PCR) analysis, Western blot analysis, alkaline phosphatase (ALP) staining/activity assays, and Alizarin red staining. In addition, the Agilent miRNA microarray system combined with qRT‐PCR analysis revealed that miR‐3679‐5p, miR‐6515‐5p, and miR‐6747‐5p were highly expressed in Exs‐Ad‐P2X7. Further functional tests and luciferase reporter assays revealed that miR‐3679‐5p and miR‐6747‐5p bound directly to the GREM‐1 protein, while miR‐6515‐5p bound to the GREM‐1 protein indirectly; these effects combined to rescue inflammation‐compromised PDLSCs from dysfunction. Thus, in addition to maintaining their robust functionality under inflammatory conditions, P2X7R gene‐modified stem cells may exert positive influences on their neighbors via a paracrine mechanism, pointing to a novel strategy for modifying the harsh local microenvironment to accommodate stem cells and promote improved tissue regeneration.

Dental injuries at the Xi'an, China Stomatological Hospital: A Retrospective Study

BACKGROUND/AIM

In order to enrich epidemiological knowledge regarding traumatic dental injuries (TDI) in China, and to further improve the treatment, prevention and education of TDI, the aim of this study was to retrospectively analyze the TDI that presented to the emergency dental department at the Stomatological Hospital in Xi'an, China.

METHODS

This retrospective study included all first-visit patients who presented with TDI at the Stomatological Hospital affiliated with the Fourth Military Medical University in Xi'an, China, between January 2013 and June 2019. Data were extracted using the terms of diagnosis of TDI from the hospital database.

RESULTS

Overall, 965 (606 males and 359 females) files were reviewed. The average age was 22.8 ± 13.4 years. Among the 2059 teeth injured (average of 2.1 teeth per patient), the maxillary incisors (1751; 85.0%) were the most prevalent teeth to present with injuries, while the main types of injuries were concussions (14.8%) enamel-dentin-fractures (14.50%) and enamel-dentin-pulp fractures (14.0%). After initial examination and diagnosis, 4.2% patients refused treatment.

CONCLUSIONS

The epidemiological statistics of TDI in Xi'an, China show consistency with other studies from around the world, but they also vary in diagnosis proportion and the choice of treatments. This information may further instruct treatment, prevention and emergency resources distribution to target the high-risk groups.

[Radiation dose and image quality of noncontrast chest CT in domestic and imported main stream manufacturers]

Objective: To compare the radiation dose and image quality of noncontrast chest CT and detection of ground-glass opacity pulmonary nodules (GGN) in domestic 128-slice spiral CT with the other CT scanners from three main stream manufacturers. Methods: From May 8, 2018 to October 31, 2018, noncontrast chest CT images from Neusoft 128-slice CT (75 males, 25 females, (42±16) years), dual-source 64-slice CT (53 males, 47 females, (50±16) years) and dual-source 128-slice CT scanners(69 males, 31 females, (62±17) years), Toshiba 128-slice CT (51 males, 49 females, (58±13) years) and GE 128-slice CT scanner (55 males, 45 females, (60±10) years) were collected in Eastern Theater Command and Tianjin People's Hospital. Radiation dose and image quality were evaluated.GGN detected both in Neusoft CT and dual-source CT scanners were used to analyze the displaying ability of lesions. Results: The noise in lung window of Neusoft CT ((37.8±4.9) HU) was higher than that of other mainstream CT scanners, and the noise in mediastinal window ((8.4±1.9) HU) was lower than that of GE 128-slice CT ((9.8±3.2) HU), but higher than that of dual-source CT and Toshiba 128-slice CT ((6.9±3.5)HU) (P<0.05). The absolute value of lung SNR in Neusoft CT was lower than that of other mainstream CT scanners, and the SNR in aorta (4.6±1.3) was lower than those of dual-source CT and Toshiba 128-slice CT(6.8±2.2) (P<0.05), but was not statistically significant compared with GE 128-slice CT (5.0±1.7). The mean CT value of upper lung ((-863±31) HU) at Neusoft CT was higher than 128-row dual-source CT ((-869±35) HU), and the mean CT value of aorta ((37±7) HU) was lower than that of Toshiba 128-slice CT((42±7) HU) and GE 128-slice CT ((45±9) HU) (P<0.05), while the mean CT values of the remaining lung and aorta were not statistically significant (P>0.05). The two readers had good to excellent consistency for image quality in five scanners (the highest kappa value=0.984). The delineation ability of Neusoft CT for GGN boundary was lower than that of dual-source CT (P<0.05), but had similar abilities to display the solid components, lobulation, burring, vacuoles, vascular bundle sign and pleural depression sign of GGN (all P>0.05). Radiation dose of Neusoft CT was lower than Toshiba 128-slice CT, but higher than dual-source 64-sliceCT and GE 128-slice CT scanners (P<0.05). Conclusions: With lower radiation dose than Toshiba 128-slice CT, Neusoft CT chest examination can meet the requirements of clinical diagnosis, but higher radiation dose and the lower image quality than dual-source CT and GE 128-slice CT shown in this study indicate further improvement is needed in terms of software and hardware.

[Endemic situation of schistosomiasis in surveillance sites of Tianmen City from 2015 to 2018]

OBJECTIVE

To monitor the change patterns of the endemic situation of schistosomiasis in Tianmen City from 2015 to 2018, so as to provide the evidence for formulating the schistosomiasis control strategy in the city.

METHODS

A total of 8 schistosomiasis surveillance sites were assigned in Tianmen City from 2015 to 2018, and the endemic situation of schistosomiasis and the related epidemiological factors were monitored.

RESULTS

During the period from 2015 to 2018, a total of 15 983 local person-times and 3 629 mobile populations were detected for schistosomiasis using an indirect hemagglutination test (IHA) in Tianmen City, and the sero-prevalence was 0.88% to 1.44% and 0.96% to 2.39%, respectively; however, no egg-positives were identified. A total of 1 245 herd-times were detected, and no egg-positives were found in bovines. In addition, the areas of snail habitats were 116.69 to 117.23 hm² and the mean densities of living snails were 0.07 to 0.17 snails/0.1 m² during the study period; however, no infections were identified in snails.

CONCLUSIONS

The endemic situation of schistosomiasis appears low in Tianmen City; however, the factors related to schistosomiasis transmission remain in the city. The integrated strategy with emphasis on the control of infectious sources should be still intensified to consolidate the schistosomiasis control achievements.

L-type voltage-gated calcium channels in stem cells and tissue engineering

L‐type voltage‐gated calcium ion channels (L‐VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L‐VGCCs in non‐excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L‐VGCCs and stem cells, and filling this gap is prescient considering the contribution of L‐VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L‐VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored.

Towards label-free distributed fiber hydrogen sensor with stimulated Raman spectroscopy

Hydrogen detection is of great importance in chemical and energy industries. Optical fiber hydrogen sensors show flexibility and compactness, and have the potential for distributed analysis. However, traditional fiber sensors encounter a challenge with light interacting with hydrogen directly because hydrogen only displays weak quadrupole absorption, and metallic palladium and platinum thin-film coatings are typically used as an optically detectable label. Here, based on stimulated Raman spectroscopy in hollow-core photonic crystal fibers, we investigate the label-free optical fiber distributed hydrogen sensors operating in the optical telecommunication band. The approach of distributed Raman measurement represents a new paradigm in fiber sensors, potentially allowing distributed chemical analysis in gas or liquid phase with high sensitivity and selectivity.

Role of the P2X7 receptor in inflammation-mediated changes in the osteogenesis of periodontal ligament stem cells

Accumulating evidence indicates that the pluripotency of periodontal ligament stem cells (PDLSCs) is compromised under inflammatory conditions; however, the underlying mechanisms remain largely unexplored. In this study, we hypothesize that the P2X7 receptor (P2X7R) is a key molecule linked to inflammation-associated impairment of PDLSCs. We first investigated P2X7R expression in PDLSCs under normal and inflammatory conditions and then determined the effect of a P2X7R agonist (BzATP) or antagonist (BBG) on PDLSC osteogenesis under various conditions. Gene-modified PDLSCs were used to further examine the role of P2X7R and the signaling pathway underlying P2X7R-enhanced osteogenesis. We found that inflammatory conditions decreased P2X7R expression in PDLSCs and reduced osteogenesis in these cells. In addition, activation of P2X7R by BzATP or overexpression of P2X7R via gene transduction reversed the inflammation-mediated decrease in PDLSC osteogenic differentiation. When selected osteogenesis-related signaling molecules were screened, the PI3K-AKT-mTOR pathway was identified as potentially involved in P2X7R-enhanced PDLSC osteogenesis. Our data reveal a crucial role for P2X7R in PDLSC osteogenesis under inflammatory conditions, suggesting a new therapeutic target to reverse or rescue inflammation-mediated changes in PDLSCs for future mainstream therapeutic uses.

Tunneling anisotropic magnetoresistance driven by magnetic phase transition

The independent control of two magnetic electrodes and spin-coherent transport in magnetic tunnel junctions are strictly required for tunneling magnetoresistance, while junctions with only one ferromagnetic electrode exhibit tunneling anisotropic magnetoresistance dependent on the anisotropic density of states with no room temperature performance so far. Here, we report an alternative approach to obtaining tunneling anisotropic magnetoresistance in α′-FeRh-based junctions driven by the magnetic phase transition of α′-FeRh and resultantly large variation of the density of states in the vicinity of MgO tunneling barrier, referred to as phase transition tunneling anisotropic magnetoresistance. The junctions with only one α′-FeRh magnetic electrode show a magnetoresistance ratio up to 20% at room temperature. Both the polarity and magnitude of the phase transition tunneling anisotropic magnetoresistance can be modulated by interfacial engineering at the α′-FeRh/MgO interface. Besides the fundamental significance, our finding might add a different dimension to magnetic random access memory and antiferromagnet spintronics.

Tunneling anisotropic magnetoresistance is promising for next generation memory devices but limited by the low efficiency and functioning temperature. Here the authors achieved 20% tunneling anisotropic magnetoresistance at room temperature in magnetic tunnel junctions with one α′-FeRh magnetic electrode.

Strategies for Automated CryoEM Data Collection Using Direct Detectors

The new generation of direct electron detectors has been a major contributor to the recent resolution revolution in cryo-electron microscopy. Optimal use of these new cameras using automated data collection software is critical for high-throughput near-atomic resolution cryo-electron microscopy research. We present an overview of the practical aspects of automated data collection in the context of this new generation of direct detectors, highlighting the differences, challenges, and opportunities the new detectors provide compared to the previous generation of data acquisition media.

FDG PET/CT in monitoring treatment of retroperitoneal fibrosis

Retroperitoneal fibrosis is an uncommon disease characterized by inflammatory fibrosis typically surrounding abdominal aorta and iliac arteries. The glucose analogue F18-fluorodeoxyglucose can be used to image inflammatory cell activity non-invasively by PET. In this report we investigated the usefulness of the FDG PET/CT in the disease activity and therapy response evaluation of retroperitoneal fibrosis.

Low dose gossypol for male contraception

AIM

To ascertain whether the side effects of gossypol, hypokalemia and irreversibility, could be avoided on dose reduction.

METHODS

Seventy-seven male volunteers were divided into 3 groups: control (22 cases), 10 mg gossypol (29 cases) and 12.5 mg (26 cases). Serum levels of testosterone, FSH and LH were measured by RIA and potassium by flame photometry. Sperm counts and motility were examined before and regularly after treatment for the evaluation of contraceptive efficacy.

RESULTS

The average sperm density and motility started to decrease significantly by the end of month 2 of medication and gradually reached the infertility levels (< 4 million/mL) in both treated groups. After that the 10 mg group was asked to take the same dose every other day for up to a total observation period of 16-18 months for the maintenance of infertility. Subjects in the 12.5 mg group did not take gossypol any more so as to observe the length of the loading dose required, but in a few, a maintenance dose of 12.5 mg every other day was instituted for a few more months. In both treated groups, none of the spouses was pregnant during the maintenance dose period. Serum levels of potassium, FSH, LH and testosterone were not significantly changed and not a single volunteer complained of myoasthenia. After cessation of drug administration, the semen data returned to pretreatment levels.

CONCLUSION

A regimen with 10 or 12.5 mg of gossypol as the daily loading dose and 35 or 43.75 mg as the weekly maintenance dose could induce infertility in male volunteers without developing hypokalemia or irreversibility.

Effects of salvianolic acid-A on rat hepatic stellate cell proliferation and collagen production in culture

AIM

To investigate the effects of salvionolic acid-A (SA-A), one of main effective components of Salvia miltiorrhiza for its antifibrotic action, on the cell proliferation and collagen production in cultured hepatic stellate cells (HSC).

METHODS

HSC were isolated through in situ perfusion of liver with pronase E and collagenase, and gradient centrifugation with Nycodenz. The cultured HSC were incubated with SA-A 0.1-100 mumol/L for 24 h. MTT spectrometric assay and intercellular incorporation of methyl-[3H]thymidine ([3H]TdR) was used to assess the cell proliferation. The amount of collagen was semi-quantified by ponceau staining and image analysis, the amount of type I collagen secretion was measured with ELISA and normalized by the total protein of cell layer. The total RNA was prepared from the control cells and the drug treated cells respectively, and the expression of pro-collagen alpha 2 (I) mRNA was semi-quantitatively analyzed with RT-PCR.

RESULTS

SA-A 100 mumol/L showed a little cytotoxity, SA-A 0.1-10 mumol/L did not influence cell morphology, and SA-A 1-100 mumol/L decreased the cell proliferation significantly in a concentration-dependent manner (P < 0.05). SA-A 1, 10, 100 mumol/L decreased the cell collagen deposition by 78.6%, 71.8%, and 61.3% of the control respectively (P < 0.05), and decreased type I collagen secretion to 53.1%, 52.6%, and 49.5% (P < 0.01 or P < 0.05). Both SA-A 1 and 10 mumol/L downregulated procollagen alpha 2 (I) mRNA expression remarkably (P < 0.05).

CONCLUSION

SA-A inhibited HSC proliferation and collagen expression. The inhibitory effect on HSC activation is the main mechanism of SA-A action against liver fibrosis.

[Effects of nine prescriptions on fever in rats induced by endotoxin]

In this paper in is reported that nine prescriptions often used in traditional Chinese medicine for the treatment of diseases with fever were tested experimentally for the effect on fever of rats induced by endotoxin. The results are as follows: Da-yuan-decoction, Gan-lu-xiao-du-pill, Lian-pu-decoction, Cai-hao-mixture, Da-huang-huang-lian-jie-du-decoction, Tao-ren-cheng-qi-decorction, Ge-gen-qin-lian-decoction, Yin-qiao-jie-du-decoction etc. can notably reduce fever in rats induced by endotoxin with the exception of Bai-hu-decoction that has no obvious effect on fever-reduction.

Inhibition of microsomal N-nitrosodimethylamine demethylase by diethyl ether and other anesthetics

The inhibitory actions of diethyl ether and several other anesthetics on the metabolism of N-nitrosodimethylamine (NDMA) and other substrates were studied with rat liver microsomes. Diethyl ether was an effective inhibitor of the low Km NDMA demethylase, showing characteristics of a competitive inhibition. Inhibition of NDMA metabolism was also observed in the liver post-mitochondrial supernatant fraction prepared from ether-anesthetized rats. Selectivity in the inhibitory action of diethyl ether was demonstrated; the ether was most effective against NDMA demethylase, less potent against p-nitroanisole demethylase and N-nitrosomethylbenzylamine demethylase, and not effective against the metabolism of aminopyrine or benzphetamine. Other anesthetics such as chloroform, isoflurane, enflurane, and halothane also effectively inhibited NDMA demethylase. The work demonstrates that diethyl ether is an efficient inhibitor of NDMA metabolism by the microsomal monooxygenase systems.

Monoclonal antibodies to ethanol-induced rat liver cytochrome P-450 that metabolizes aniline and nitrosamines

Hybridomas were prepared from mouse myeloma cells and spleen cells derived from female BALB/c mice that had been immunized with a partially purified ethanol-induced rat liver cytochrome P-450 (P-450et). Monoclonal antibodies (MAbs) produced by the hybridomas were screened for binding to P-450et with a radioimmunoassay. Thirty-one independent hybrid clones produced MAbs that had a high affinity for P-450et. Each clone produced MAbs of a single subclass of the mouse immunoglobulins IgG1, IgG2a, IgM, or IgA. Ten of the 31 MAbs also immunoprecipitated P-450et as determined by Ouchterlony double-immunodiffusion analyses. One of the MAbs was tested for cross-reactivity with other rabbit and rat liver cytochromes P-450 and was found not to cross-react with rat liver P-450 induced by either phenobarbital, beta-naphthoflavone, or rabbit liver P-450LM2 or P-450LM4. Nine of the MAbs were tested for cross-reactivity with rat liver clofibrate-induced P-450, rat liver pregnenolone-16-alpha-carbonitrile-induced P-450, and a human liver P-450. All the MAbs showed no cross-reactivity except for one MAb which cross-reacted with both pregnenolone-16-alpha-carbonitrile and human P-450 and three MAbs which cross-reacted with human P-450. Three antigen-precipitating MAbs and four nonprecipitating MAbs were tested for their effects on the aniline p-hydroxylase activity of liver microsomes of untreated rats and from rats treated with acetone, pyrazole, methylpyrazole, or imidazole. One of the seven MAbs tested, 1-91-3, inhibited enzyme activity of acetone-, pyrazole-, or methylpyrazole-induced microsomes by 54, 47, and 48%, respectively. This indicates that at least 50% of microsomal cytochrome P-450 aniline p-hydroxylase activity in the latter is a function of a P-450 enzyme that contained the epitope to which the MAb 1-91-3 is directed. With untreated and imidazole-induced microsomes, 32 and 21% inhibition of the enzyme activity was observed. In reconstituted systems containing phospholipid and NADPH-cytochrome P-450 reductase, MAb 1-91-3 inhibited aniline p-hydroxylase activity of purified ethanol-induced P-450et and acetone-induced P-450 by more than 90%. Nitrosodimethylamine demethylase activity of acetone-induced rat microsomes was inhibited by the various MAbs up to 77% and the activity of the purified acetone-induced P-450 was inhibited up to 92%.(ABSTRACT TRUNCATED AT 400 WORDS)