Inhibition of silkworm vacuolar-type ATPase activity by its inhibitor Bafilomycin A1 induces caspase-dependent apoptosis in an embryonic cell line of silkworm.

Vacuolar-type ATPase (V-ATPase) is a type of hydrogen ion transporter located in the vesicular membrane-like system, which mediates active transport and intracellular acidification in various compartments. In mammals, V-ATPase has been reported to play a key role in cell proliferation and apoptosis. The studies of V-ATPase in silkworm mainly focus on the acidification regulation of midgut and silk gland and immune resistance. However, there are few reports about the function of silkworm V-ATPase on cell proliferation, autophagy, and apoptosis. Thus, the function of V-ATPase in a cell line of Bombyx mori (BmE) was investigated by treating the cell line with bafilomycin A1, a specific inhibitor of V-ATPase. Cell counting kit 8 (CCK8) and flow cytometry analysis showed that bafilomycin A1 treatment decreased the cell proliferation activity, affected the cell cycle progression and induced cell apoptosis. LysoTracker Red staining showed that the target of bafilomycin A1 is lysosome. The expression of all autophagy-related genes ( BmATG5, BmATG6, and BmATG8) decreased, indicating that cell autophagy was inhibited. The analysis of the apoptosis pathway demonstrated that inhibiting the activity of V-ATPase of BmE cells could promote mitochondria to release cytochrome C, inhibit the expression of BmIAP, and activate the caspase cascade to induce apoptosis. All these findings systematically illustrate the effects of V-ATPase on the proliferation, autophagy, and apoptosis in BmE cells, and provide new ideas and a theoretical basis for further study on the function of V-ATPase in BmE.

[Effects of nanopolystyrene nanoplastic exposure on the development and neurotoxicity of fetal rats during gestation].

Objective: To investigate the effects of polystyrene nanoplastics (PS-NPs) exposure during gestation on the growth and neurotoxicity of fetal rats. Methods: Twenty-seven SD pregnant rats were randomly divided into 9 groups with three rats in each group. The experimental group of PS-NPs was given 0.5, 2.5, 10 and 50 mg/kg of PS-NPs suspension with different particle sizes (25 and 50 nm) by gavage, wihe the control group was given ultrapure water by gavage. The time of gavage is from the 1st to the 18th day of pregnancy. The morphological changes of the placenta were observed; compare the number of male and female fetuses, live/dead/absorbed fetuses, body weight, body length, placental weight, and organ coefficients of kidney, liver, brain and intestine of fetal rats; the prefrontal cortex, hippocampus and striatum of the fetal rats were taken to measure related biochemical indicators. Results: Compared with the control group, the placenta of the PS-NPs exposed group was found to have structural damage, which increased in a dose-dependent manner. The area ratio of trophoblast was significantly increased (P＜0.05), and the area ratio of labyrinth was significantly decreased (P＜0.05); In the prefrontal cortex, hippocampus and striatum of fetal rats, the levels of IL-1ß, IL -6 and TNF-α were significantly increased in the 10 and 50 mg/kg PS-NPs exposed group (P＜0.05), and more significantly elevated in the 25 nm group than those in the 50 nm group at 10 mg/kg exposure (P＜0.05) the CAT activity was significantly decreased in 2.5, 10 and 50 mg/kg PS-NPs exposure groups (P＜0.05), while the SOD and GSH-Px activities were significantly decreased in 25 nm exposure groups and 2.5, 10 and 50 mg/kg 50 nm PS-NPs exposure groups (P＜0.05), the MDA content was significantly increased in 10, 50 mg/kg 25 nm PS-NPs exposure groups and 50 mg/kg 50 nm PS-NPs exposure groups (P＜0.05). Conclusion: Maternal PS-NPs exposure during gestation may affect the growth and development of fetal rats by damaging the placental barrier and produce neurotoxicity in fetal rats, causing oxidative stress and inflammatory responses in various brain regions, and smaller particle sizes and higher doses of polystyrene nanoplastic exposure have more significant neurotoxic effects on the offspring.

[Effects of early life PM2.5 exposure on prefrontal cortex of offspring male rats].

Objective: To investigate the effects of PM2.5 exposure at different stages of early life on the prefrontal cortex of offspring rats. Methods: Twelve pregnant SD rats were randomly divided into four groups: Control group (CG), Maternal pregnancy exposure group (MG), Early postnatal exposure group (EP) and Perinatal period exposure group (PP), 3 rats in each group. The pregnant and offspring rats were exposed to clean air or 8-fold concentrated PM2.5. MG was exposed from gestational day (GD) 1 to GD21. EP was exposed from postnatal day (PND) 1 to PND21, and PP was exposed from GD1 to PND21. After exposure, the prefrontal cortex of 6 offspring rats in each group was analyzed. HE staining was used to observe the pathological damage in the prefrontal cortex. ELISA was employed to detect neuroinflammatory factors, and HPLC/MSC was applied to determine neurotransmitter content. Western blot and colorimetry were applied for detecting astrocyte markers and oxidative stress markers, respectively. Results: Compared with MG and CG, the pathological changes of prefrontal cortex in PP and EP were more obvious. Compared with MG and CG, the neuroinflammatory factors (IL-1, IL-6, TNF-α) in PP and EP were increased significantly (P＜0.01), the level of MT were decreased significantly (P＜0.05), and the level of oxytocin (OT) showed a downward trend; the level of neurotransmitter ACh was also increased significantly (P＜0.01). Compared with MG and CG, the GFAP level of PP and EP showed an upward trend, the level of oxidative stress index SOD in PP and EP was decreased significantly (P＜0.01), and the level of ROS was increased significantly (P＜0.01). Compared with the offspring rats of CG and MG, the CAT level of PP was decreased significantly (P＜0.01, P＜0.05). Compared with the offspring rats of CG, the CAT level of EP was decreased significantly (P＜0.05). There was no significant difference in IL-1, IL-6, TNF-α, MT, OT, ACh, GFAP, SOD, ROS and CAT levels between PP and EP, or MG and CG. Conclusion: PM2.5 exposure in early life has adverse effects on the prefrontal cortex of offspring male rats, and early birth exposure may be more sensitive.

Desulfovibrio fairfieldensis-Derived Outer Membrane Vesicles Damage Epithelial Barrier and Induce Inflammation and Pyroptosis in Macrophages.

Sulfate-reducing bacteria Desulfovibrio fairfieldensis is an opportunistic pathogen that widely exists in the human intestine and can cause severe infectious diseases. However, the mechanisms contributing to its pathogenesis remain of great interest. In this study, we aim to investigate the outer membrane vesicles (OMVs) secreted by D. fairfieldensis and their pathogenic effect. The OMVs separated by ultracentrifugation were spherical and displayed a characteristic bilayer lipid structure observed by transmission electron microscopy, with an average hydrodynamic diameter of 75 nm measurement using the particle size analyzer. We identified 1496 and 916 proteins from D. fairfieldensis and its OMVs using label-free non-target quantitative proteomics, respectively. The 560 co-expressed proteins could participate in bacterial life activities by function prediction. The translocation protein TolB, which participates in OMVs biogenesis and transporting toxins was highly expressed in OMVs. The OMVs inhibited the expression of tight junction proteins OCCLUDIN and ZO-1 in human colonic epithelial cells (Caco-2). The OMVs decreased the cell viability of monocyte macrophages (THP-1-Mφ) and activated various inflammatory factors secretion, including interferon-γ (IFN-γ), tumor necrosis factor (TNF-α), and many interleukins. Further, we found the OMVs induced the expression of cleaved-gasdermin D, caspase-1, and c-IL-1ß and caused pyroptosis in THP-1-Mφ cells. Taken together, these data reveal that the D. fairfieldensis OMVs can damage the intestinal epithelial barrier and activate intrinsic inflammation.

Influence of Short-Term Consumption of Hericium erinaceus on Serum Biochemical Markers and the Changes of the Gut Microbiota: A Pilot Study.

Hericium erinaceus (H. erinaceus) is widely studied as a medicinal and edible fungus. Recent studies have shown that H. erinaceus has protective effects for diseases, such as inflammatory bowel disease and cancer, which are related to gut microbiota. To investigate the benefits of H. erinaceus intake on gut microbiota and blood indices in adulthood, we recruited 13 healthy adults to consume H. erinaceus powder as a dietary supplement. Blood changes due to H. erinaceus consumption were determined by routine hematological examination and characterized by serum biochemical markers. Microbiota composition was profiled by 16S ribosomal RNA gene sequencing. Results showed that daily H. erinaceus supplementation increased the alpha diversity within the gut microbiota community, upregulated the relative abundance of some short-chain fatty acid (SCFA) producing bacteria (Kineothrix alysoides, Gemmiger formicilis, Fusicatenibacter saccharivorans, Eubacterium rectale, Faecalibacterium prausnitzii), and downregulated some pathobionts (Streptococcus thermophilus, Bacteroides caccae, Romboutsia timonensis). Changes within the gut microbiota were correlated with blood chemical indices including alkaline phosphatase (ALP), low-density lipoprotein (LDL), uric acid (UA), and creatinine (CREA). Thus, we found that the gut microbiota alterations may be part of physiological adaptations to a seven-day H. erinaceus supplementation, potentially influencing beneficial health effects.

Crystallographic observation of the movement of the membrane-distal domain of the T7SS core component EccB1 from Mycobacterium tuberculosis.

The protein EccB1, a core component of the type VII secretion system (T7SS) of Mycobacterium tuberculosis, has been identified as an ATPase and is essential for the secretion of virulence factors by the ESX-1 system. In a previous study, EccB1 structures were determined in two different conformations. Here, two new conformations are identified and described. These four conformations present snapshots of the swinging movement of the membrane-distal domain A2. The movement of this domain involves conformational changes in two flexible loops (loop A, residues 243-264, and loop B, residues 324-341) which are rich in proline and glycine residues and connect domain A2 to domains C1 and B2. It is proposed that the movement of this domain is related to the ATPase activity of EccB1 and its homologues, as well as to the substrate transport of ESX secretion systems.

[Correlation between the area of arterial blood gases graph and the acid-base disturbance in 92 cases with chronic obstructive pulmonary disease].

OBJECTIVE: To study the correlation between the area of arterial blood gases graph (ABGG) and the acid-base disturbance (ABD). METHODS: Using the software developed by ourselves, the results of arterial blood gases and concomitant electrolyte (K(+), Na(+), Cl(-), HCO(3)(-)) determination in 313 episodes were analyzed in 92 cases with chronic obstructive pulmonary diseases (COPD) during hospitalization, and the correlation was studied. RESULTS: (1)On admission, among 92 cases, in 9 cases the results of blood gas analysis were in the area of compensated ventilation and deranged gas exchange (area IV), in 82 cases the results were in the area of insufficient ventilation and deranged gas exchange (area V), and 1 case in the area of excessive ventilation and deranged gas exchange (area VI). There were 8 types of the ABDs, and respiratory acidosis (RAC)+metabolic alkalosis (MAL), RAC, RAC+metabolic acidosis (MAC) with increase in anion gap (AG) ranked in above order. (2)At the time of discharge, in 2 cases the distribution of ABGG was in the normal area (area I), 5 cases in the area IV, 20 cases in the area V, and 1 case in the area VI. There were 5 types of the ABDs. RAC+MAL and RAC ranked in the first two positions. (3)During hospitalization, the correlations between the area of ABGG and ABD in 313 episodes were as follows: ABD normal and MAC of AG increased in the area I; ABD normal and MAL, MAC with AG increased, RAC+MAC, respiratory alkalosis (RAL)+MAL, MAL+MAC of AG increased, RAC+MAL+MAC of AG increased and RAL+MAL+MAC of AG increased in the area IV; RAC, MAL, RAC+MAL, RAC+MAC of AG increased, MAL+MAC of AG increased, and RAC+MAL+MAC of AG increased in the area V; MAC of AG increased, RAC+MAC, RAL+MAL, MAL+MAC of AG increased, and RAL+MAL+MAC of AG increased in the area VI. No ABD occurred in the areas II and III. CONCLUSION: The correlation between ABGG and ABD can be analyzed easily and quickly and the accuracy of results is ensured by using the software.

[Development and its clinical application of an acid-base balance computer software].

OBJECTIVE: To develop acid-base balance computer software for estimating acid-base disturbance rapidly and accurately. METHODS: The data module was set up, based on Henderson-Hasselbalch (H-H) and compensation formula, and the program was written with Delphi 5.0. RESULTS: The right RESULTS was 100.0 percent in 118 cases of acid-base disturbance patients by the software, while those with the right RESULTS was 89.8 percent by hands (P<0.05). In 20 cases pure acid-base disturbance, 70 cases double acid-base disturbance and 28 cases with triple acid-base disturbance, it took only (9.0+/-0.6) seconds, (8.9+/-1.3) seconds and (9.1+/-1.6)seconds respectively, with software, while which were much less than those by hands ((20.4+/-16.8) seconds, (92.4+/-45.3) seconds and (128.6+/-66.4) seconds, respectively, P<0.001). CONCLUSION: This software has a terse interface, by which the acid-base disturbance was concluded exactly and quickly.

[Clinical application of a software for the analysis of arterial blood gases graph in 231 patients with chronic obstructive pulmonary disease].

OBJECTIVE: To evaluate the clinical significance of a computer software for the analysis of arterial blood gases graph (ABGG) in chronic obstructive pulmonary disease(COPD). METHODS: The software was developed with Win98 as the operating platform and the visual software Delphi 5.0 from Borland Company, and it was used for evaluation of the changes in arterial blood gases (ABG) of 231 COPD cases. RESULTS: (1) With the software it took only (4.7+/-0.5)s to draw and analyze an ABGG of COPD patients during oxygen inhalation; the time was much shorter than manual analysis (90.2+/-4.9)s, P<0.001. (2) During acute attack, the distributions of the arterial blood gases parameters on ABGG were as follows: 55.4% of cases in the area of insufficient ventilation and deranged gas exchange (area 5), 22.9% of cases in the area of compensated ventilation and deranged gas exchange (area 4), 21.6% of cases in the area of excessive ventilation and deranged gas exchange (area 6). (3) When the COPD patient's condition improved, the location of ABG in ABGG shifted from area 5 to area 4 or area 6. The distributions of the arterial blood gases parameters on ABGG of 106 cases on admission were significantly different from those at the time of discharge. (4) With deterioration of patient's condition, it shifted to area 5. Before death, the arterial blood gases parameters were exclusively in the area 5. CONCLUSION: The computer software for ABGG shortened the time to draw and evaluate ABG during oxygen inhalation, and it could reflect the changes in patient's condition promptly.