Mycobacterium tuberculosis Mce2D protein blocks M1 polarization in macrophages by inhibiting the ERK signaling pathway.

Macrophages play a pivotal role in controlling Mycobacterium infection, and the pathogen thrives in the event of immune evasion and immunosuppression of macrophages. Mammalian cell entry proteins (Mce) are required for Mycobacterium tuberculosis (M. tb) growth and the host cell's initial phagocytosis and cytokine response. Mce2D protein is one of a family of proteins that infect M. tb; however, the function and mechanism of action remain unclear. In this study, we constructed the Mce2D knockout strain using Mycobacterium smegmatis to study the function of Mce2D in the infection of macrophages. The results indicated that compared to the knockout strain, the release of proinflammatory cytokines (TNF-α and IL-1ß) reduced when WT strain infected the macrophages. Moreover, Mce2D boosted the metabolism of oxidized fatty acids, increased the energy supply of TCA, and lowered the glycolysis of glucose in macrophages after bacterial infection, all of which prevented the polarization of macrophages to M1, which was driven by the fact that Mce2D blocked ERK2 phosphorylation by interacting with ERK2 through its DEF motif. This, in turn, promoted nuclear translocation of HIF-1α, allowing signal accumulation, which increased the HIF-1α transcription levels. Finally, the mouse infection experiment showed that Mce2D caused blockage of M1 polarization of alveolar macrophages, resulting in reduced bactericidal activity and antigen presentation, weakening Th1 cell-mediated immune response and helping bacteria escape the immune system. Our results reveal that Mce2D causes immune escape by blocking M1 polarization in macrophages, providing potential targets for the rational design of therapies against M. tb infection.

Hsa_circ_0007460 affects the survival of intracellular Mycobacterium tuberculosis by regulating autophagy and apoptosis of macrophages.

Circular RNA (circRNA) is a category of non-coding RNAs characterized by the absence of a 5'-cap and 3'-poly(A) tail, and participates in the physiological processes of various human diseases. Nonetheless, the diagnostic and functional significance of circRNAs in active pulmonary tuberculosis (ATB) remains uncertain. Consequently, the purpose of this study is to investigate whether hsa_circ_0007460 can be employed as a potential diagnostic biomarker in ATB patients and explore its function. The result of real-time quantitative fluorescent PCR (RT-qPCR) validated a notable increase in the expression of hsa_circ_0007460 in the peripheral blood of 32 ATB patients, as well as in THP-1 human macrophages infected with Bacillus Calmette Guerin (BCG) which is an attenuated strain of Mycobacterium bovis. Additionally, the receiver operating curve (ROC) illustrated that the area under the ROC curve (AUC), sensitivity and specificity were 0.7474, 76.67%, and 78.13% respectively. RNase R, Actinomycin D and other experiments confirmed that hsa_circ_0007460 was stabler than its linear mRNA, indicating that hsa_circ_0007460 has potential as a diagnostic biomarker of ATB. Furthermore, Western blot (WB), Cell Counting Kit-8 (CCK-8), plate counting, and immunofluorescence experiments revealed that hsa_circ_0007460 could regulate apoptosis and autophagy of macrophages. The downstream miRNAs and mRNAs were subsequently predicted using bioinformatics, and the hsa circ 0007460/hsa-miR-3127-5p/PATZ1 axis was built. These above results suggest that hsa_circ_0007460 is substantially up-regulated in the peripheral blood of patients with ATB and can be utilized as a potential diagnostic biomarker. In addition, hsa_circ_0007460 can promote apoptosis of macrophages and inhibit autophagy of macrophages, thereby promoting the survival of BCG.

The hsa_circ_0002371/hsa-miR-502-5p/ATG16L1 axis modulates the survival of intracellular Mycobacterium tuberculosis and autophagy in macrophages.

Circular RNAs (circRNAs) play a critical role in pathological mechanisms of Mycobacterium tuberculosis (Mtb) and can be used as a new biomarker for active tuberculosis (ATB) diagnosis. Therefore, we identified significantly dysregulated circRNAs in ATB patients and healthy controls (HC) and explored their molecular mechanism. We found that hsa_circ_0002371 was significantly up-regulated in PBMCs of ATB patients and Mycobacterium tuberculosis H37Rv- or Mycobacterium bovis bacillus Calmette Guerin (BCG)-infected THP-1 cells. Functional experiments demonstrated that hsa_circ_0002371 inhibited autophagy in BCG-infected THP-1 cells and promoted intracellular BCG survival rate. In terms of mechanism, hsa_circ_0002371 facilitated the expression of hsa-miR-502-5p, as shown by bioinformatics and dual-luciferase reporter gene analysis, respectively. Notably, hsa-miR-502-5p inhibited autophagy via suppressing autophagy related 16 like 1 (ATG16L1) in BCG-infected macrophages and thus promoting intracellular BCG growth. In summation, hsa_circ_0002371 increased the suppression of hsa-miR-502-5p on ATG16L1 and inhibited autophagy to promote Mtb growth in macrophages. In Conclusion, our data suggested that hsa_circ_0002371 was significantly up-regulated in the PBMCs of ATB patients compared with HC. The hsa_circ_0002371/hsa-miR-502-5p/ATG16L1 axis promoted the survival of intracellular Mtb and inhibited autophagy in macrophages. Our findings suggested hsa_circ_0002371 could act as a potential diagnostic biomarker and therapeutic target.

Mycobacterium tuberculosis hijacks host macrophages-derived interleukin 16 to block phagolysosome maturation for enhancing intracellular growth.

The discovery of promising cytokines and clarification of their immunological mechanisms in controlling the intracellular fate of Mycobacterium tuberculosis (Mtb) are necessary to identify effective diagnostic biomarkers and therapeutic targets. To escape immune clearance, Mtb can manipulate and inhibit the normal host process of phagosome maturation. Phagosome maturation arrest by Mtb involves multiple effectors and much remains unknown about this important aspect of Mtb pathogenesis. In this study, we found that interleukin 16 (IL-16) is elevated in the serum samples of Tuberculosis (TB) patients and can serve as a specific target for treatment TB. There was a significant difference in IL-16 levels among active TB, latent TB infection (LTBI), and non-TB patients. This study first revealed that macrophages are the major source of IL-16 production in response to Mtb infection, and elucidated that IL-16 can promote Mtb intracellular survival by inhibiting phagosome maturation and suppressing the expression of Rev-erbα which can inhibit IL-10 secretion. The experiments using zebrafish larvae infected with M. marinum and mice challenged with H37Rv demonstrated that reducing IL-16 levels resulted in less severe pathology and improved survival, respectively. In conclusion, this study provided direct evidence that Mtb hijacks the host macrophages-derived interleukin 16 to enhance intracellular growth. It is suggesting the immunosuppressive role of IL-16 during Mtb infection, supporting IL-16 as a promising therapeutic target.

Nighttime warming and nitrogen addition effects on the microclimate of a freshwater wetland dominated by Phragmites australis.

The critical impacts of microclimate on carbon (C) cycling have been widely reported. However, the potential effects of global change on wetland microclimate remain unclear, primarily because of the absence of field manipulative experiment in inundated wetland. This study was designed to examine the effects of nighttime warming and nitrogen (N) addition on air, water, and sediment temperature and also reveal the controlling factors in a Phragmites australis dominated freshwater wetland on the North China Plain. Nighttime warming increased daily air, water, and sediment temperature by 0.24 °C, 0.27 °C, and 0.36 °C, respectively. The diurnal temperature range of water was decreased by 0.44 °C under nighttime warming, whereas warming had no effect on diurnal temperature range of air and sediment. In addition, N addition caused a reduction of 0.20 °C and 0.14 °C in daily water and sediment temperature by increasing vegetation coverage. There was a significant interaction between nighttime warming and N addition on water temperature. Furthermore, the vapor pressure deficit is the main factor affecting the extent of the warming-induced increases in air temperature. The changes of height and leaf area index of Phragmites australis are responsible for the cooling effects in the N addition plots. This study provides empirical evidence for the positive climate warming - microclimate feedback in freshwater wetland. However, N deposition leads to decreased water and sediment temperature. Our findings highlight the importance of incorporating the differential impacts of nighttime warming and N addition on air, water, and sediment temperature into the predictions of wetland C cycling responses to climate change.

3D-Printed Filters for Efficient Heavy Metal Removal from Water Using PLA@CS/HAP Composites.

Chitosan/Hydroxyapatite composites, enriched with relatively active -NH2 and -OH groups, have emerged as promising adsorbents for heavy metal removal. In this study, we harnessed the potential of CS/HAP composites by developing monolithic PLA@CS/HAP filters utilizing 3D printing and freeze-drying techniques. These filters possess both macroscopic and microscopic porous structures, endowing them with exceptional capabilities for removing heavy metals from water. The adsorption properties of CS/HAP composites were explored by varying the dosage, duration, and initial concentrations of copper ions. The maximum adsorption capacity for Cu2+ was determined to be approximately 119+/-1 mg/g at the natural pH and 298 K. Notably, the monolithic PLA@CS/HAP filters demonstrated remarkable efficiency in the removal of copper ions, with 90% of copper ions effectively removed within a mere 2-h period in a cyclic adsorption experiment. Furthermore, the PLA@CS/HAP filters exhibited a robust dynamic Cu2+ removal capacity (80.8% or even better in less than 35 min) in a dynamic adsorption experiment. Importantly, all materials employed in this study were environmentally friendly. In summary, the PLA@CS/HAP filter offers advantages such as ease of preparation, eco-friendliness, versatility, and broad applicability in diverse wastewater treatment scenarios, thereby presenting a significant potential for practical implementation.

B21 DNA vaccine expressing ag85b, rv2029c, and rv1738 confers a robust therapeutic effect against latent Mycobacterium tuberculosis infection.

Latent tuberculosis infection (LTBI) treatment is known to accelerate the decline in TB incidence, especially in high-risk populations. Mycobacterium tuberculosis (M. tb) expression profiles differ at different growth periods, and vaccines protective and therapeutic effects may increase when they include antigenic compositions from different periods. To develop a post-exposure vaccine that targets LTBI, we constructed four therapeutic DNA vaccines (A39, B37, B31, and B21) using different combinations of antigens from the proliferation phase (Ag85A, Ag85B), PE/PPE family (Rv3425), and latent phase (Rv2029c, Rv1813c, Rv1738). We compared the immunogenicity of the four DNA vaccines in C57BL/6j mice. The B21 vaccine stimulated the strongest cellular immune responses, namely Th1/Th17 and CD8+ cytotoxic T lymphocyte responses. It also induced the generation of strengthened effector memory and central memory T cells. In latently infected mice, the B21 vaccine significantly reduced bacterial loads in the spleens and lungs and decreased lung pathology. In conclusion, the B21 DNA vaccine can enhance T cell responses and control the reactivation of LTBI.

Dehydrocostuslactone attenuated oxygen and glucose deprivation/reperfusion-induced PC12 cell injury through inhibition of apoptosis and autophagy by activating the PI3K/AKT/mTOR pathway.

The purpose of this study is to investigate the protective effect of dehydrocostuslactone (DHL) on PC12 cells injury induced by oxygen and glucose deprivation/reperfusion (OGD/R) and its possible mechanism on the PI3K/AKT/mTOR pathway. The maestro 11.1 software was used to predict the binding sites of DHL with LC3, Beclin-1, PI3K, AKT, mTOR, Bax, Bcl-2, Caspase-3, Caspase-9, and Caspase-7. We used a cellular model of 2 h of OGD and 24 h of reperfusion to mimic cerebral ischemia-reperfusion injury. Cells were treated with DHL during the reperfusion phase. The docking results showed that DHL had binding sites with LC3, Beclin-1, PI3K, AKT, mTOR, Bax, Bcl-2, Caspase-3, Caspase-9, and Caspase-7. The expression levels of autophagy-related proteins, LC3 and Beclin-1 increased while P-PI3K, P-AKT, and P-mTOR decreased. Apoptosis-related proteins, namely, Bax, Cyto-c, Caspase-3, Caspase-7, Caspase-9 increased, but the anti-apoptosis Bcl-2 protein decreased. However, DHL effectively inhibited these undesirable changes induced by OGD/R in PC12 cells. Our results suggested that DHL attenuated OGD/R-induced neuronal injury by inhibiting apoptosis and autophagy by activating PI3K/AKT/mTOR signaling. This inhibition can improve cell survival and offer evidence for the beneficial effects of DHL on the nervous system.

The role of traditional Chinese medicine in the treatment of cognitive dysfunction in type 2 diabetes.

ETHNOPHARMACOLOGICAL RELEVANCE: Diabetic cognitive dysfunction (DCD) is mainly one of the complications of type 2 diabetes mellitus (T2DM) with complex and obscure pathogenesis. Extensive evidence has demonstrated the effectiveness and safety of traditional Chinese medicine (TCM) for DCD management. AIM OF THE STUDY: This review attempted to systematically summarize the possible pathogenesis of DCD and the current Chinese medicine on the treatment of DCD. MATERIALS AND METHODS: We acquired information of TCM on DCD treatment from PubMed, Web of Science, Science Direct and CNKI databases. We then dissected the potential mechanisms of currently reported TCMs and their active ingredients for the treatment of DCD by discussing the deficiencies and giving further recommendations. RESULTS: Most TCMs and their active ingredients could improve DCD through alleviating insulin resistance, microvascular dysfunction, abnormal gut microbiota composition, inflammation, and the damages of the blood-brain barrier, cerebrovascular and neurons under hyperglycemia conditions. CONCLUSIONS: TCM is effective in the treatment of DCD with few adverse reactions. A large number of in vivo and in vitro, and clinical trials are still needed to further reveal the potential quality markers of TCM on DCD treatment.

Synthesis and characterization of activated carbon from sugar beet residue for the adsorption of hexavalent chromium in aqueous solutions.

A series of micro-mesoporous activated carbons (ACs) were prepared from sugar beet residue by a two-step method including KOH chemical activation and were used for Cr(vi) removal from aqueous solutions. Several characterization techniques, including SEM, TEM, N2 adsorption, XRD, FTIR, and Raman spectroscopy, were used to determine the chemical and physical characteristics of the ACs, and the adsorption properties of the ACs were tested. The results indicated that the high specific surface area of the ACs reached 2002.9 m2 g-1, and the micropore surface area accounts for 85% of the total area. The optimal conditions for achieving the maximum Cr(vi) adsorption capacity of 163.7 mg g-1 by the ACs were activation with a KOH/carbon ratio of 3.0, an initial Cr(vi) concentration of 400 mg L-1, an adsorbent dose of 2.0 g L-1 and pH of 4.5. Therefore, the ACs exhibit excellent adsorption performance for removing Cr(vi) from aqueous solutions. According to an investigation of the adsorption process, the adsorption isotherm is most consistent with the Langmuir isotherm model, and the adsorption kinetics were well described by the pseudo-second-order model.

Costunolide attenuates oxygen­glucose deprivation/reperfusion­induced mitochondrial­mediated apoptosis in PC12 cells.

The present study investigated the effect of costunolide (CT), a compound extracted from Aucklandia lappa Decne, to attenuate oxygen­glucose deprivation/reperfusion (OGD/R)­induced mitochondrial­mediated apoptosis in PC12 cells. The present study used molecular docking technology to detect the binding of CT with mitochondrial apoptotic protein targets. A model of oxygen­glucose deprivation for 2 h and reperfusion for 24 h in PC12 cells was used to mimic cerebral ischemic injury. Cell viability and damage were measured using the Cell Counting kit­8 and lactate dehydrogenase (LDH) cytotoxicity assay kits. Cellular apoptosis was analyzed using flow cytometry. A fluorescence microscope determined intracellular [Ca2+] and mitochondrial membrane potential. Furthermore, immunofluorescence and Western blot analyses were used to detect the expression of apoptosis­associated proteins. CT contains binding sites with Caspase­3, Caspase­9 and Caspase­7. CT markedly enhanced cell viability, inhibited LDH leakage, increased intracellular [Ca2+], stabilized the mitochondrial membrane potential, increased the expression of Bcl­2 and inhibited the expression of Apaf­1, Bax, cleaved­caspase­7, cleaved­caspase­9 and cleaved­caspase­3. CT may markedly protect PC12 cells from damage caused by OGD/R, and its mechanism is associated with blocking the calcium channel and inhibiting mitochondrial­mediated apoptosis.

Corn stalk-based activated carbon synthesized by a novel activation method for high-performance adsorption of hexavalent chromium in aqueous solutions.

A simple activation method involving treatment with KOH solution was used to synthesize activated carbon (ACs) with micro-meso pores from the agricultural waste of corn stalks. The activation reagent, KOH solution, was easily separated for recycling by centrifugation from the pre-treated corn stalks, and the pollution in the carbonization process was greatly reduced. The morphology and structure of the ACs were characterized by SEM, TEM, N2 adsorption, XRD, FT-IR and Raman analysis. The prepared carbon was applied as an adsorbent for the removal of Cr(VI) in a batch adsorption process. The effect of the concentration of KOH solution on the structure, morphology and Cr(VI) adsorption performance of the synthesized ACs was investigated. The characterization results revealed that some functional groups in the corn stalks were removed by pretreatment with KOH solution and micro-meso porous structures were generated. The ACs showed high adsorption performance for Cr(VI), and the maximum adsorption ability of the ACs prepared by activation with 4% KOH solution reached 89.5 mg g-1 at an adsorbent dosage of 2.5 g·L-1 and pH value of 4.5.

Mu-Xiang-You-Fang protects PC12 cells against OGD/R-induced autophagy via the AMPK/mTOR signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Mu-Xiang-You-Fang (MXYF) is a classic prescription of Hui medicine. It is composed of five herbs and has been used to treat ischemic stroke for many years. However, the potential pharmacological mechanisms of MXYF remain unclear. The present research is aimed to investigate the protective effect and possible mechanisms of MXYF treatment in an in vitro model of cerebral ischemia-reperfusion injury. MATERIALS AND METHODS: An oxygen-glucose deprivation and reperfusion (OGD/R) model of PC12 cells was established. The effect of MXYF on the cell viability after OGD/R injury was determined using a cell counting kit (CCK-8) assay. The colorimetric method was used to determine the lactate dehydrogenase (LDH) leakage rate. The calcium concentration was determined by the chemical fluorescence method, and mitochondrial membrane potential was determined using flow cytometry. Monodansylcadaverine (MDC) staining and electron microscopic analysis were then conducted to detect autophagy after oxygen-glucose deprivation and reperfusion in PC12 cells. Immunofluorescence and western blot analyses were used to detect the expression of proteins associated with autophagy. RESULTS: It was found that MXYF (1, 2, 4 µg/mL) could significantly increase cell viability and mitochondrial membrane potential and decrease the calcium concentration and LDH release rate in PC12 cells. After OGD/R injury in PC12 cells, the number of autophagosomes and autophagolysosome significantly increased. MXYF (4 µg/mL) inhibited the autophagy induced by OGD/R and inhibited the expression of LC3, beclin1, p-AMPK, and ULK1. In contrast, the expression of p-mTOR, p-p70s6k, and p62 was significantly enhanced. CONCLUSIONS: These findings suggest that MXYF inhibits autophagy after OGD/R-induced PC12 cell injury through the AMPK-mTOR pathway. Thus, MXYF might have therapeutic potential in treating ischemic stroke.

Occurrence and Characterization of Dimethachlon Insensitivity in Sclerotinia sclerotiorum in Jiangsu Province of China.

Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is the main fungal disease of oilseed rape (Brassica napus) in China. Numerous fungicide applications are required for control. Dimethachlon, one of the dicarboximide fungicides, has been the major fungicide for disease control after benzimidazole resistance became widespread. Fungal populations were collected throughout Jiangsu Province between 2006 and 2007 in order to determine their sensitivity to dimethachlon. A total of 1,066 single-sclerotium isolates of S. sclerotiorum were collected, and most of the isolates were considered sensitive to dimethachlon. Five isolates collected in Yancheng and Changzhou showed normal growth at 5 µg/ml dimethachlon with the resistance factor ≈10 (resistance factor was estimated as ratios between the EC50 values of resistant isolates and the average EC50 values of sensitive ones) compared to the sensitive isolates (EC50 is the concentration of fungicide causing 50% reduction in growth). Through in vitro selection for resistance to the fungicide, 25 dimethachlon-resistant mutants were derived from 10 wild-type isolates of S. sclerotiorum. The resistance factors for the isolates ranged from 198 to 484, and the isolates were considered highly resistant to dimethachlon. Therefore, at least two different mechanisms of resistance seem to be involved: one that may provide a moderate resistance (insensitivity) and a second that may give a high resistance level under laboratory conditions. There was positive cross-resistance between dimethachlon and other dicarboximide fungicides, such as iprodione and procymidone, in these S. sclerotiorum isolates. The field dimethachlon-insensitive and the laboratory-induced dimethachlon-resistant isolates appeared to have mycelial growth, sclerotial production, and pathogenicity comparable to their wild-type parental isolates. Also, results of osmotic tests showed that there were no significant difference in mycelial radial growth between the field dimethachlon-sensitive and field dimethachlon-insensitive isolates on potato dextrose agar plates amended with 2, 4, 6, or 8% (wt/vol) NaCl, but the laboratory-induced dimethachlon-resistant isolates grew significantly more slowly than their wild-type sensitive parents under all concentrations of NaCl. Because these studies yielded a high frequency of laboratory resistance in S. sclerotiorum, together with the occurrence of field insensitivity, appropriate precautions against resistance development in natural populations should be taken.

[Progress and prospect of bio-jet fuels industry in domestic and overseas].

We reviewed the progress of the bio-jet fuels industry in recent years and systematically analyzed the technical routes that have been approved or in the pipeline for approval by ASTM D7566. In addition, we highlighted a novel pathway to produce drop-in fuel by near-critical hydrolysis of waste cooking oils or algal oils followed by catalytic decarboxylation. Also, we introduced the source of oils and fats feedstock and the domestic bio-jet fuel industry status during the 12th Five-Year-Plan period. Based on our own research, we discussed the prospect of the bio-jet fuel industry and future research needs.

Yi qi qing re gao attenuates podocyte injury and inhibits vascular endothelial growth factor overexpression in puromycin aminonucleoside rat model.

Proteinuria is the hallmark of chronic kidney disease. Podocyte damage underlies the formation of proteinuria, and vascular endothelial growth factor (VEGF) functions as an autocrine/paracrine regulator. Yi Qi Qing Re Gao (YQQRG) has been used to treat proteinuria for more than two decades. The objective of this study was to investigate the protective effect and possible mechanisms of YQQRG on puromycin aminonucleoside (PAN) rat model. Eighty male Sprague-Dawley rats were randomized into sham group, PAN group, PAN + YQQRG group, and PAN + fosinopril group. Treatments were started 7 days before induction of nephrosis (a single intravenous injection of 40 mg/kg PAN) until day 15. 24 h urinary samples were collected on days 5, 9, and 14. The animals were sacrificed on days 3, 10, and 15, respectively. Blood samples and renal tissues were obtained for detection of biochemical and molecular biological parameters. YQQRG significantly reduced proteinuria, elevated serum albumin, and alleviated renal pathological lesions. YQQRG inhibited VEGF-A, nephrin, podocin, and CD2AP mRNA expression and elevated nephrin, podocin, and CD2AP protein levels starting on day 3. In conclusion, YQQRG attenuates podocyte injury in the rat PAN model through downregulation of VEGF-A and restoration of nephrin, podocin, and CD2AP protein expression.