The present study aimed to explore whether hydrogen sulfide (H₂S) improved hypoxic pulmonary hypertension (HPH) in rats by inhibiting aerobic glycolysis-pyroptosis. Male Sprague-Dawley (SD) rats were randomly divided into normal group, normal+NaHS group, hypoxia group, and hypoxia+NaHS group, with 6 rats in each group. The control group rats were placed in a normoxic (21% O₂) environment and received daily intraperitoneal injections of an equal volume of normal saline. The normal+NaHS group rats were placed in a normoxic environment and intraperitoneally injected with 14 μmol/kg NaHS daily. The hypoxia group rats were placed in a hypoxia chamber, and the oxygen controller inside the chamber maintained the oxygen concentration at 9% to 10% by controlling the N₂ flow rate. An equal volume of normal saline was injected intraperitoneally every day. The hypoxia+NaHS group rats were also placed in an hypoxia chamber and intraperitoneally injected with 14 μmol/kg NaHS daily. After the completion of the four-week modeling, the mean pulmonary artery pressure (mPAP) of each group was measured using right heart catheterization technique, and the right ventricular hypertrophy index (RVHI) was weighed and calculated. HE staining was used to observe pathological changes in lung tissue, Masson staining was used to observe fibrosis of lung tissue, and Western blot was used to detect protein expression levels of hexokinase 2 (HK2), pyruvate dehydrogenase (PDH), pyruvate kinase isozyme type M2 (PKM2), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), GSDMD-N-terminal domain (GSDMD-N), Caspase-1, interleukin-1β (IL-1β) and IL-18 in lung tissue. ELISA was used to detect contents of IL-1β and IL-18 in lung tissue. The results showed that, compared with the normal control group, there were no significant changes in all indexes in the normal+NaHS group, while the hypoxia group exhibited significantly increased mPAP and RVHI, thickened pulmonary vascular wall, narrowed lumen, increased collagen fibers, up-regulated expression levels of aerobic glycolysis-related proteins (HK2 and PKM2), up-regulated expression levels of pyroptosis-related proteins (NLRP3, GSDMD-N, Caspase-1, IL-1β, and IL-18), and increased contents of IL-1β and IL-18. These changes of the above indexes in the hypoxia group were significantly reversed by NaHS. These results suggest that H₂S can improve rat HPH by inhibiting aerobic glycolysis-pyroptosis.
Animals ; Rats, Sprague-Dawley ; Male ; Hypertension, Pulmonary/metabolism* ; Glycolysis/drug effects* ; Hydrogen Sulfide/therapeutic use* ; Hypoxia/complications* ; Rats ; Pyroptosis/drug effects*

The aim of this study was to investigate the contribution of lung zinc ions to pathogenesis of lung ischemia/reperfusion (I/R) injury in rats. Male Sprague Dawley (SD) rats were randomly divided into control group, lung I/R group (I/R group), lung I/R + low-dose zinc chloride group (LZnCl₂+I/R group), lung I/R + high-dose ZnCl₂ group (HZnCl₂+I/R group), lung I/R + medium-dose ZnCl₂ group (MZnCl₂+I/R group) and TPEN+MZnCl₂+I/R group (n = 8 in each group). Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure the concentration of zinc ions in lung tissue. The degree of lung tissue injury was analyzed by observing HE staining, alveolar damage index, lung wet/dry weight ratio and lung tissue gross changes. TUNEL staining was used to detect cellular apoptosis in lung tissue. Western blot and RT-qPCR were used to determine the protein expression levels of caspase-3 and ZIP8, as well as the mRNA expression levels of zinc transporters (ZIP, ZNT) in lung tissue. The mitochondrial membrane potential (MMP) of lung tissue was detected by JC-1 MMP detection kit. The results showed that, compared with the control group, the lung tissue damage, lung wet/dry weight ratio and alveolar damage index were significantly increased in the I/R group. And in the lung tissue, the concentration of Zn²⁺ was markedly decreased, while the cleaved caspase-3/caspase-3 ratio and apoptotic levels were significantly increased. The expression levels of ZIP8 mRNA and protein were down-regulated significantly, while the mRNA expression of other zinc transporters remained unchanged. There was also a significant decrease in MMP. Compared with the I/R group, both MZnCl₂+I/R group and HZnCl₂+I/R group exhibited significantly reduced lung tissue injury, lung wet/dry weight ratio and alveolar damage index, increased Zn²⁺ concentration, decreased ratio of cleaved caspase-3/caspase-3 and apoptosis, and up-regulated expression levels of ZIP8 mRNA and protein. In addition, the MMP was significantly increased in the lung tissue. Zn²⁺ chelating agent TPEN reversed the above-mentioned protective effects of medium-dose ZnCl₂ on the lung tissue in the I/R group. The aforementioned results suggest that exogenous administration of ZnCl₂ can improve lung I/R injury in rats.
Animals ; Reperfusion Injury/pathology* ; Male ; Rats, Sprague-Dawley ; Rats ; Chlorides/administration & dosage* ; Lung/pathology* ; Zinc Compounds/administration & dosage* ; Apoptosis/drug effects* ; Caspase 3/metabolism* ; Cation Transport Proteins/metabolism*

In this study, we investigated the effects of Panax notoginseng saponins (PNS) on pulmonary vascular remodeling and ADAM10/Notch3 pathway in pulmonary arterial hypertension (PAH). PAH rat model was established, and male Sprague Dawley (SD) rats were randomly divided into control group, monocrotaline (MCT) group and MCT+PNS group, with 10 rats in each group. Rats in the control group were intraperitoneally injected with equal volume of normal saline. Rats in the MCT group was injected intraperitoneally with 60 mg/kg MCT on the first day, and then with the same volume of normal saline every day. Rats in the MCT+PNS group was injected intraperitoneally with 60 mg/kg MCT on the first day, and then with 50 mg/kg PNS every day. The modeling time of each group lasted for 21 days. After the model was established, the mean pulmonary artery pressure (mPAP) was measured by right heart catheterization technique, the right ventricular hypertrophy index (RVHI) was calculated, the microscopic morphology and changes of pulmonary vascular wall were observed by HE and Masson staining, and the expressions of ADAM10, Notch3, Hes-1, P27, PCNA, Caspase-3 proteins and mRNA in pulmonary vascular tissue of rats were detected by Western blot and qPCR. The expression and localization of Notch3 and α-SMA were detected by immunofluorescence staining. The protein expression of ADAM10 was detected by immunohistochemical staining. The results showed that compared with the control group, mPAP, RVHI, pulmonary vessels and collagen fibers in the MCT group were significantly increased, the expressions of ADAM10, Notch3, Hes-1, and PCNA protein and mRNA were significantly increased, while the expressions of P27 and Caspase-3 protein and mRNA were decreased significantly. Compared with the MCT group, mPAP and RVHI were significantly decreased, pulmonary vessels were significantly improved and collagen fibers were significantly reduced, the expressions of protein and mRNA of ADAM10, Notch3, Hes-1, and PCNA were decreased in MCT+PNS group, but the expressions of protein and mRNA of P27 and Caspase-3 were increased slightly. The results of immunofluorescence showed that Notch3 and α-SMA staining could overlap, which proved that Notch3 was expressed in smooth muscle cells. The expression of Notch3 in the MCT group was increased significantly compared with that in the control group, while PNS intervention decreased the expression of Notch3. Immunohistochemical staining showed that compared with the control group, the amount of ADAM10 in the MCT group was increased significantly, and the expression of ADAM10 in the MCT+PNS group was decreased compared with the MCT group. These results indicate that PNS can improve the PAH induced by MCT in rats by inhibiting ADAM10/Notch3 signaling pathway.
Animals ; Male ; Rats ; Caspase 3/metabolism* ; Collagen ; Disease Models, Animal ; Hypertension, Pulmonary/drug therapy* ; Monocrotaline/adverse effects* ; Panax notoginseng/chemistry* ; Proliferating Cell Nuclear Antigen/pharmacology* ; Pulmonary Arterial Hypertension ; Pulmonary Artery/metabolism* ; Rats, Sprague-Dawley ; Receptor, Notch3/genetics* ; RNA, Messenger ; Saline Solution ; Signal Transduction ; Saponins/pharmacology*

Manganese is an element essential for living organisms. Development of industrial technologies and exploitation of mineral resources have led to the release of large amount of Mn(Ⅱ) into the environment, posing a serious threat to human health. Bioremediation can remove the Mn(Ⅱ) from the environment rapidly and effectively without generating secondary pollution, thus received increasing attention. This review summarized the diversity and distribution of Mn(Ⅱ) removal microorganisms and the associated mechanisms, followed by discussing the effect of environmental factors on microbial Mn(Ⅱ) removal. Finally, the challenges and prospects for bioremediation of Mn(Ⅱ) polluted wastewater were proposed.
Biodegradation, Environmental ; Humans ; Manganese ; Oxidation-Reduction ; Waste Water

Animals ; Autophagy ; Ischemia ; Lung ; Lung Injury ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury

The aim of this study was to investigate the regulatory role of retinoid X receptor (RXR)-mediated oxidative stress pathway in rat pulmonary ischemia/reperfusion injury (PIRI) and the underlying mechanism. Seventy-seven male Sprague-Dawley (SD) rats were randomly divided into 7 groups (n = 11): control group, sham group, sham+9-cis-retinoid acid (9-cRA, RXR agonist) group, sham+HX531 (RXR inhibitor) group, ischemia/reperfusion (I/R) group, I/R+9-cRA group, and I/R+HX531 group. The unilateral lung I/R model was established by obstruction of left lung hilus for 30 min and reperfusion for 180 min in vivo. The rats in I/R+9-cRA and I/R+HX531 groups were given intraperitoneal injection of 9-cRA and HX531 before thoracotomy. After reperfusion, the left lung tissue was taken to evaluate the lung tissue injury, and the oxidative stress-related indexes of the lung tissue were detected by the corresponding kits. The lung tissue morphology and the ultrastructure of the alveolar epithelial cells were observed by HE staining and transmission electron microscope, respectively. The protein expression of RXR in lung tissue was observed by immunofluorescence labeling method, and the expression level of nuclear factor E2-related factor (Nrf2) protein was detected by Western blot. The results showed that, compared with the sham group, the I/R group exhibited obviously injured lung tissue, decreased SOD activity, increased MDA content and MPO activity, and down-regulated expression level of Nrf2 protein. Compared with the I/R group, the I/R+9-cRA group showed alleviated lung tissue injury, increased activity of SOD, decreased MDA content and MPO activity, and up-regulated expression levels of RXR and Nrf2 protein. The above-mentioned improvement effects of 9-cRA were reversed by HX531 treatment. These results suggest that RXR activation can effectively protect the lung tissue against I/R injury, and the mechanism may involve the activation of Nrf2 signaling pathway, the enhancement of antioxidant level and the reduction of oxidative stress response.
Animals ; Lung ; physiopathology ; Male ; NF-E2-Related Factor 2 ; physiology ; Oxidative Stress ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; Retinoid X Receptors ; physiology ; Signal Transduction

OBJECTIVE: To observe the pulmonary vascular remodeling in rats with pulmonary hypertension induced by hypoxia and hypercapnia, and to explore the role of endoplasmic reticulum stress in pulmonary hypertension. METHODS: Forty SD rats were random-ly divided into four groups:normoxic control group (N), hypoxia hypercapnia group (HH), ERS inhibitor 4-phenylbutyric acid group (4-PBA), endoplasmic reticulum stress (ERS) pathway agonist tunicamycin group (TM), ten rats in each group.The mean pulmona-ry artery pressure (mPAP), mean carotid artery pressure (mCAP) and right ventricular hypertrophy index of rats in each group were measured.Pulmonary artery smooth muscle cells were identified by immunofluorescence α-smooth muscle actin (α-SMA).Morphologi-cal changes of lung tissue and pulmonary artery were observed by electron microscope.The apoptotic index of pulmonary artery smooth muscle cells in each group was detected by TUNEL.Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression of glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP), c-Jun N-terminal kinase (JNK) and cysteinyl aspartate specific proteinase-12 (caspase-12) mRNA and protein in each group. RESULTS: ①Compared with the N group, the mPAP, the ratio of right ventricle weight to left ventricle plus ventricular septum weight[RV/(LV+S)]and the ratio of pulmonary artery wall area to total tube area (WA/TA) were increased (<0.01), and the ratio of pulmonary artery luminal area to total tube area (LA/TA) were decreased (<0.01), pulmonary artery smooth muscle cell apoptosis index were decreased (<0.05 or <0.01) in HH group, 4-PBA group and TM group.ERS related protein and mRNA expressions were increased, the differences were statistically significant.②Compared with the HH group, the mPAP, [RV/(LV+S)]and WA/TA of 4-PBA group were decreased ( <0.01), LA/TA and pulmonary artery smooth muscle cell apoptosis index were increased (<0.01, <0.05).The expressions of ERS related protein and mRNA were all decreased (<0.05 or <0.01).③Compared with the HH group, the mPAP, [RV/(LV+S)]and WA/TA of TM group were increased (<0.05 or <0.01), pulmonary artery middle layer thickened, LA/TA and pulmonary artery smooth muscle cell apoptotic index were decreased (<0.01).ERS related protein and mRNA expressions were increased with statistical significance except GRP78 protein. CONCLUSIONS Pulmonary vascular remodeling in rats with pulmonary hypertension induced by hypoxia and hypercapnia may be related to the excessive proliferation of pulmonary artery smooth muscle cells and too little apopto-sis;ERS related factors (JNK, caspase-12 and CHOP) are involved in the regulation of pulmonary hypertension induced by hypoxia hypercapnia.
Animals ; Endoplasmic Reticulum Stress ; Hypercapnia ; Hypertension, Pulmonary ; Hypoxia ; Pulmonary Artery ; Rats ; Rats, Sprague-Dawley

OBJECTIVE: To investigate the effect of Yiqi Wenyang Huoxue Huatan Fang (YWHHF) on alleviating hypoxia-hypercarbia pulmonary hypertension by inhibiting endothelial-mesenchymal transition (EndoMT) BMP-7/Smads pathway. METHODS: Fifty male healthy SD rats of clean grede, weighting (180~220) g, were randomly divided into 5 groups (=10):normoxia group (N), hypoxia-hypercarbia group (HH); YWHHF high dose group (YH), middle dose group (YM) and low dose group (YL). The rats in N group were kept in normal oxygen environment, the remaining four groups were intermittently exposed to hypoxia-hypercarbia environment (9%~11% O, 5%~6% CO) for 4 weeks, 6 days a week, 8 hours per day. The rats in YH, YM, YL groups were received YWHHF gavage in a dosageof 0.6, 0.3, 0.15g/kg respectively (3 ml/kg),the rats in N and HH groups were received equal volume of normal saline. After 4 weeks, the mean pulmonary arterial pressure(mPAP) was detected,the right ventricular free wall and left ventricle plus ventricular septum were isolated to determine the right ventricular hypertrophy index. Lung ultrastructural changes were surveyed under an electronic microscopy, the changes of pulmonary artery structure surveyed by immunofluorescence, the mRNA levels of alpha-smooth muscle actin (α-SMA)、platelet endothelial cell adhesion molecule-1 (CD31)、bone morphogenetic protein-7 (BMP-7)、drosophila mothers against decapentaplegic protein1/5/8 (Smad1/5/8) were detected by RT-PCR, and the protein levels of α-SMA、CD31、BMP-7、p-Smad1/5/8 and Smad1/5/8 were detected by Western blot. RESULTS: Compared with N group, mPAP and the right ventricular hypertrophy index were increased,some significant injuries also were discovered under microscopic observation,the mRNA and protein expression of α-SMA was increased, and the mRNA expressions of CD31、BMP-7、Smad1/5/8 were decreased in the other four groups, the protein expressions of CD31、BMP-7、p-Smad1/5/8 were decreased(<0.05). Compared with HH group, the above changes in YH、YM、YL groups were all improved (<0.05). CONCLUSIONS YWHHF can inhibit EndoMT to alleviate pulmonary hypertension, and the mechanism may be related to the promotion of the expression of BMP-7/Smads pathway.
Animals ; Hypercapnia ; Hypertension, Pulmonary ; chemically induced ; Hypoxia ; Male ; Pulmonary Artery ; Rats ; Rats, Sprague-Dawley

OBJECTIVES: To investigate the effects of dexmedetomidine (Dex) on injury of A549 cells induced by hypoxia/reoxygenation(H/R)and the influence of C/EBP homologous protein (CHOP) expression. METHODS: Logarithmic growth phase A549 cells(it originated from alveolar type Ⅱ epithelial cell line) were randomly divided into 4 groups (=10):normoxic control group (N), Dex group (D), hypoxia/reoxygenation group (H), hypoxia/reoxygenation + Dex group(HD). At the beginning of modeling, 1 nmol/L Dex was puted into D and HD groups. N and D groups were cultured in the normoxic incubator for 30 h. H and HD group were incubated in the anoxic cultivation for 6 h, fo llowed by normoxic culture for 24 h. Then A549 cells were observed under the inverted microscope to observe the morphological changes. Cell activity was detected by cell counting Kit-8(CCK-8) and the apoptosis index(AI) was detected by in situ end labeling (TUNEL) method. The expression of CHOP、glucose-regulated protein of molecular weight 78 kDa (Grp78)、cysteinyl aspirate-specificprotease-3 (caspase-3) protein and CHOP、Grp78 mRNA were detected by Western blot and RT-PCR. RESULTS: Compared with N group, the number of adherent cells in H group decreased significantly, and cell morphology changed. The absorbance value in H group decreased obviously (<0. 01). The AI value and expression of CHOP, Grp78, caspase-3 proteins and CHOP, Grp78 mRNA were significantly increased (<0.01). Compared with H group, the cell damage in HD group was decreased, the absorbance value increased (<0.01), the number of apoptosis cells decreased relatively (<0.01), the expression of CHOP, caspase-3 protein and CHOP mRNA decreased (<0. 01). CONCLUSIONS Dex has notable effects against H/R injury, which may be related to effective inhibition of apoptosis mediated by the CHOP's signal path.
A549 Cells ; Apoptosis ; Cell Hypoxia ; Dexmedetomidine ; pharmacology ; Humans ; Transcription Factor CHOP ; physiology

OBJECTIVE: To investigate the effects of excessive endoplasmic reticulum stress on lung ischemia/reperfusion (I/R) induced myocardial injury in mice. METHODS: Forty healthy SPF male C57BL/6J mice were divided into 4 groups randomly (=10):sham operation group (Sham group), lung I/R group (I/R group), endoplasmic reticulum stress (ERS) pathway agonist Tunicamycin group (TM) and ERS inhibitor 4-phenyl butyric acid group (4-PBA). The model of lung I/R injury was established by clamping the left hilum of lung for 30 min followed by 180 min of reperfusion. In sham group, only sternotomy was performed, the hilum of lung was not clamped, and the mice were mechanically ventilated for 210 min. In TM and 4-PBA groups, TM 1mg/kg and 4-PBA 400 mg/kg were injected intraperitoneally, respectively, at 30 min before establishment of the model. At 180 min of reperfusion, blood samples were collected from the orbit for determination of myocardial enzyme. The animals were then sacrificed, and hearts were removed for determination of light microscope, TUNEL, Caspase 3 enzymatic activity, real-time polymerase chain reaction and Western blot. RESULTS: Compared with sham group, the cardiomyocytes had obvious damage under light microscope, and the serum creatine kinase-MB (CK-MB) and lactic dehydrogenase (LDH) activities, apoptosis index and Caspase 3 enzymatic activity were increased significantly, the expressions of p-Jun N-terminalkinase(p-JNK), Caspase 12, CCAAT/enhancer-binding protein homologous protein (CHOP) and glucose regulated protein 78(GRP78) protein and mRNA were up-regulated in I/R, TM and 4-PBA groups (<0.01). Compared with I/R group, the cardiomyocytes damage was obvious under light microscope, and the serum CK-MB and LDH activities, apoptosis index and Caspase 3 enzymatic activity were increased significantly, the expressions of p-JNK, Caspase 12, CHOP and GRP78 protein and mRNA were up-regulated in group TM; while all above changes were relieved in group 4-PBA (<0.01). Compared with TM group, the cardiomyocytes damage was relieved under light microscope, and the serum CK-MB and LDH activities, apoptosis index and Caspase 3 enzymatic activity were decreased significantly, the expressions of p-JNK, Caspase 12,CHOP and GRP78 protein and mRNA were down-regulated in group 4-PBA. CONCLUSIONS The excessive endoplasmic reticulum stress participates in myocardial injury induced by lung ischemia/reperfusion (I/R) and inhibit excessive endoplasmic reticulum stress response can relieved myocardial injury.
Animals ; Apoptosis ; Caspase 12 ; Caspase 3 ; metabolism ; Creatine Kinase, MB Form ; blood ; Endoplasmic Reticulum Stress ; Heart Injuries ; physiopathology ; Heat-Shock Proteins ; metabolism ; L-Lactate Dehydrogenase ; blood ; Lung ; pathology ; MAP Kinase Kinase 4 ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Myocardium ; pathology ; Random Allocation ; Reperfusion Injury ; Transcription Factor CHOP ; metabolism