PIK3CA regulates development of diabetes retinopathy through the PI3K/Akt/mTOR pathway.

OBJECTIVE: To explore their association with the development of diabetes retinopathy (DR), single nucleotide polymorphism (SNP) mutations were screened out by high-throughput sequencing and validated in patients diagnosed with DR. To understand the role of PIK3CA in the pathogenesis of DR and explore the relationship between PIK3CA,phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR),and DR, the effect of PIK3CA.rs17849079 mutation was investigated in a DR cell model. METHODS: Twelve patients diagnosed with DR at the Qinghai Provincial People's Hospital from September 2020 to June 2021 were randomly selected as the case group, while 12 healthy subjects of similar age and gender who underwent physical examination in Qinghai Provincial People's Hospital physical examination center during the same period were randomly selected as the control group. Blood samples (2 mL) were collected from both groups using EDTA anticoagulant blood collection vessels and frozen at -20°C for future analysis. SNP mutations were detected by high-throughput sequencing, and the shortlisted candidates were subjected by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The detected SNP candidates were verified by expanding the sample size (first validation: 56 patients in the case group and 58 controls; second validation: 157 patients in the case group and 96 controls). A lentivirus vector carrying mutated or wild-type PIK3CA.rs17849079 was constructed. ARPE-19 cells were cultured in a medium supplemented with 10% fetal bovine serum (FBS) to establish a DR cell model. PIRES2-PIK3CA-MT and PIRES2-PIK3CA-WT vectors were transfected into DR model cells, which were categorized into control, mannitol, model, empty vector, PIK3CA wild-type, and PIK3CA mutant-type groups. Cell activity was detected by the cell counting kit (CCK)-8 assay, and cellular apoptosis was evaluated by flow cytometry. Glucose concentration and levels of cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-1ß were detected using enzyme-linked immunosorbent assay kits. The expression of PIK3CA, AKT1, mTOR, and VEGF genes was detected by real-time quantitative polymerase chain reaction (RT-qPCR), while the expression of PI3K, p-PI3K, AKT1, p-AKT1, mTOR, p-mTOR, and VEGF proteins was detected by western blotting. RESULTS: The mutated SNPs were mainly enriched in the PI3K/AKT pathway, calcium ion pathway, and glutamatergic synaptic and cholinergic synaptic signaling pathways. Seven SNPs, including PRKCE.rs1533476, DNAH11.rs10485983, ERAP1.rs149481, KLHL1.rs1318761, APOBEC3C.rs1969643, FYN.rs11963612, and KCTD1.rs7240205, were not related to the development of DR. PIK3CA.rs17849079 was prone to C/T mutation. The risk of DR increased with the presence of the C allele and decreased in the presence of the T allele. High glucose induced the expression of PIK3CA and VEGF mRNAs as well as the expression of PI3K, p-PI3K, p-AKT1, p-mTOR, and VEGF proteins in ARPE-19 cells, which led to secretion of inflammatory factors TNF-αand IL-1, cell apoptosis, and inhibition of cell proliferation. The PIK3CA.rs17849079 C allele accelerated the progression of DR. These biological effects were inhibited when the C allele of PIK3CA.rs17849079 was mutated to T allele. CONCLUSION: The mutated SNP sites in patients with DR were mainly enriched in PI3K/AKT, calcium ion, and glutamatergic synaptic and cholinergic synaptic signaling pathways. The rs17849079 allele of PIK3CA is prone to C/T mutation where the C allele increases the risk of DR. High glucose activates the expression of PIK3CA and promotes the phosphorylation of PI3K, which leads to the phosphorylation of AKT and mTOR. These effects consequently increase VEGF expression and accelerate the development of DR. The C to T allele mutation in PIK3CA.rs17849079 can play a protective role and reduce the risk of DR.

Differentially expressed circRNAs in peripheral blood samples as potential biomarkers and therapeutic targets for acute angle-closure glaucoma.

Glaucoma is the leading cause of irreversible blindness globally. Circular RNAs (circRNAs) play vital roles in various biological processes as microRNA (miRNA) sponges and, thus, have been investigated as potential biomarkers and therapeutic targets in numerous human diseases. However, the underlying mechanisms of circRNAs in the pathogenesis of glaucoma remain unclear. Therefore, transcriptome sequencing was performed to identify relevant circRNAs in peripheral blood samples from patients with primary angle-closure glaucoma. Bioinformatics analysis was performed to investigate the potential roles of differentially expressed circRNAs (DEcircRNAs) in the pathogenesis of glaucoma. In total, 481 differentially expressed genes in addition to 345 DEcircRNAs were identified in patients with glaucoma. Based on a public database, targeted gene analysis identified 11 DEcircRNAs that potentially regulate the expression of five genes as miRNA sponges in glaucoma. In addition, quantitative reverse transcription PCR analysis verified that expression of the circRNA hsa-circ-0000745 was positively correlated with the expression of NEAT1 as a potential target gene. These results suggest that DEcircRNAs are involved in a gene expression regulatory network related to immune cell function and progression of glaucoma. Thus, DEcircRNAs in peripheral blood are potential biomarkers and therapeutic targets for glaucoma.

E3 ubiquitin ligase Siah1 aggravates NAFLD through Scp2 ubiquitination.

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver disorders and accompanied by multiple metabolic dysfunctions. Although excessive lipid accumulation in hepatocytes has been identified as a crucial mediator of NAFLD development, the underlying mechanisms are very complicated and remain largely unknown. In this study, we reported that upregulated expression of the seven in absentia homolog 1 (Siah1) in the liver exacerbated NAFLD progression. Conversely, Siah1 downregulation markedly alleviated the high fat diet-induced accumulation of hepatic fat and expression of genes related to lipid metabolism in vitro and in vivo. The mechanistic study revealed that Siah1 interacted with sterol carrier protein 2 (Scp2) and promotes its ubiquitination and degradation, suggesting that Siah1 is an important activator of Scp2 ubiquitination in the context of NAFLD. Our results demonstrated that Siah1 regulated the lipid accumulation in NAFLD by interacting with Scp2. Thus, this study presents Siah1 as a promising therapeutic target in the development of NAFLD.

Association of CFH and MAP1LC3B gene polymorphisms with age-related macular degeneration in a high-altitude population.

AIM: To evaluate the association of complement factor H (CFH) and microtubule-associated protein 1 light chain 3 beta (MAP1LC3B) gene polymorphisms with the risk of age-related macular degeneration (AMD) in a high-altitude population. METHODS: The study group consisted of 172 participants with symptoms of AMD who were examined and diagnosed between January 2019 and June 2020. The control group was composed of 120 healthy individuals. Each participant was required to provide two milliliters of peripheral blood for DNA extraction. Two single nucleotide polymorphisms (SNPs) of CFH (rs1061170 and rs800292) and two SNPs of MAP1LC3B (rs8044820 and rs9903) were genotyped. The genotypes and allele frequencies of the SNPs in the study and control groups were further compared using Chi-square and Fisher's exact tests. RESULTS: In a high-altitude population, the nominally significant differences of rs800292 and rs9903's genotype AG frequencies were observed in the AMD group (P=0.034 and 0.004, respectively). The frequencies of allele G of rs800292 and allele A of rs9903 were also significantly different in the AMD group compared to the control [(P=0.034, OR=0.70, 95%CI: 0.50-0.98) and (P=0.004, OR=1.60, 95%CI: 1.15-2.22), respectively]. No significant differences in the genotype distributions (P=0.16 and 0.40, respectively) and allele frequencies (P>0.05) of rs1061170 and rs8044820 were observed in the AMD group. CONCLUSION: Genotype AG of rs800292 may be a protective factor for AMD. Conversely, rs9903 seems to be a risk factor for AMD. Therefore, allele G of rs800292 may be a protective factor, and allele A of rs9903, a risk factor for AMD in Qinghai high-altitude population.

Bone morphogenetic protein 4 inhibits pulmonary fibrosis by modulating cellular senescence and mitophagy in lung fibroblasts.

BACKGROUND: Accumulation of myofibroblasts is critical to fibrogenesis in idiopathic pulmonary fibrosis (IPF). Senescence and insufficient mitophagy in fibroblasts contribute to their differentiation into myofibroblasts, thereby promoting the development of lung fibrosis. Bone morphogenetic protein 4 (BMP4), a multifunctional growth factor, is essential for the early stage of lung development; however, the role of BMP4 in modulating lung fibrosis remains unknown. METHODS: The aim of this study was to evaluate the role of BMP4 in lung fibrosis using BMP4-haplodeleted mice, BMP4-overexpressed mice, primary lung fibroblasts and lung samples from patients with IPF. RESULTS: BMP4 expression was downregulated in IPF lungs and fibroblasts compared to control individuals, negatively correlated with fibrotic genes, and BMP4 decreased with transforming growth factor (TGF)-ß1 stimulation in lung fibroblasts in a time- and dose-dependent manner. In mice challenged with bleomycin, BMP4 haploinsufficiency perpetuated activation of lung myofibroblasts and caused accelerated lung function decline, severe fibrosis and mortality. BMP4 overexpression using adeno-associated virus 9 vectors showed preventative and therapeutic efficacy against lung fibrosis. In vitro, BMP4 attenuated TGF-ß1-induced fibroblast-to-myofibroblast differentiation and extracellular matrix (ECM) production by reducing impaired mitophagy and cellular senescence in lung fibroblasts. Pink1 silencing by short-hairpin RNA transfection abolished the ability of BMP4 to reverse the TGF-ß1-induced myofibroblast differentiation and ECM production, indicating dependence on Pink1-mediated mitophagy. Moreover, the inhibitory effect of BMP4 on fibroblast activation and differentiation was accompanied with an activation of Smad1/5/9 signalling and suppression of TGF-ß1-mediated Smad2/3 signalling in vivo and in vitro. CONCLUSION: Strategies for enhancing BMP4 signalling may represent an effective treatment for pulmonary fibrosis.

Intracellular hydroxyproline imprinting following resolution of bleomycin-induced pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease with few treatment options. The poor success in developing anti-IPF strategies has impelled researchers to reconsider the importance of the choice of animal model and assessment methodologies. Currently, it is still not settled whether the bleomycin-induced lung fibrosis mouse model finally returns to resolution. METHODS: This study aimed to follow the dynamic fibrotic features of bleomycin-treated mouse lungs over extended durations through a combination of the latest technologies (micro-computed tomography imaging and histological detection of degraded collagens) and traditional methods. In addition, we also applied immunohistochemistry to explore the distribution of all hydroxyproline-containing molecules. RESULTS: As determined by classical biochemical methods, total lung hydroxyproline contents reached a peak at 4 weeks after bleomycin injury and maintained a steady high level thereafter until the end of the experiments (16 weeks). This result seemed to partially contradict with the changes of other fibrosis evaluation parameters, which indicated a gradual degradation of collagens and a recovery of lung aeration after the fibrosis peak. This inconsistency was well reconciled by our data from immunostaining against hydroxyproline and fluorescent peptide staining against degraded collagen, together showing large amounts of hydroxyproline-rich degraded collagen fragments detained and enriched within the intracellular regions at 10 or 16 weeks rather than at 4 weeks after bleomycin treatment. CONCLUSIONS: Our present data not only offer respiratory researchers a new perspective towards the resolution nature of mouse lung fibrosis, but also remind them to be cautious when using the hydroxyproline content assay to evaluate the severity of fibrosis.

Sodium Tanshinone IIA Sulfonate Attenuates Cigarette Smoke Extract-Induced Mitochondrial Dysfunction, Oxidative Stress, and Apoptosis in Alveolar Epithelial Cells by Enhancing SIRT1 Pathway.

Emphysema is one of the most important phenotypes for chronic obstructive pulmonary disease (COPD). Apoptosis in alveolar epithelial cells (AECs) causes the emphysematous alterations in the smokers and patients with COPD. Sirtuin 1 (SIRT1) is able to attenuate mitochondrial dysfunction, oxidative stress, and to modulate apoptosis. It has been shown that sodium tanshinone IIA sulfonate (STS), a water-soluble derivative of tanshinone IIA, protects against cigarette smoke (CS)-induced emphysema/COPD in mice. However, the mechanisms underlying these findings remain unclear. Here, we investigate whether and how STS attenuates AEC apoptosis via a SIRT1-dependent mechanism. We found that STS treatment decreased CS extract (CSE)-induced apoptosis in human alveolar epithelial A549 cells. STS reduced oxidative stress, improved mitochondrial function and mitochondrial membrane potential (ΔΨm), and restored mitochondrial dynamics-related protein expression. Moreover, STS promoted mitophagy, and increased oxidative phosphorylation protein levels (complexes I-IV) in CSE-stimulated A549 cells. The protective effects of STS were associated with SIRT1 upregulation, because SIRT1 inhibition by EX 527 significantly attenuated or abolished the ability of STS to reverse the CSE-induced mitochondrial damage, oxidative stress, and apoptosis in A549 cells. In conclusion, STS ameliorates CSE-induced AEC apoptosis by improving mitochondrial function and reducing oxidative stress via enhancing SIRT1 pathway. These findings provide novel mechanisms underlying the protection of STS against CS-induced COPD.

LncRNA Nqo1-AS1 Attenuates Cigarette Smoke-Induced Oxidative Stress by Upregulating its Natural Antisense Transcript Nqo1.

Evidence of the involvement of long noncoding RNAs (lncRNAs) in the pathogenesis of chronic obstructive pulmonary disease (COPD) is growing but still largely unknown. This study aims to explore the expression, functions and molecular mechanisms of Fantom3_F830212L20, a lncRNA that transcribes in an antisense orientation to Nqo1.We name this lncRNA as Nqo1 antisense transcript 1 (Nqo1-AS1). The distribution, expression level and protein coding potential of Nqo1-AS1 were determined. The effects of Nqo1-AS1 on cigarette smoke (CS)-induced oxidative stress were also evaluated. The results showed that Nqo1-AS1 were mainly located in the cytoplasm of mouse alveolar epithelium and had a very low protein coding potential. Nqo1-AS1 (or its human homologue) was increased with the increase of CS exposure. Nqo1-AS1 overexpression enhanced the mRNA and protein levels of Nqo1 and Serpina1 mRNA expression, and attenuated CS-induced oxidative stress, whereas knockdown of Nqo1-AS1 significantly decreased Nqo1 and Serpina1 mRNA expressions, and aggravated CS-induced oxidative stress. Nqo1-AS1 increased Nqo1 mRNA stability and upregulated Nqo1 expression through antisense pairing with Nqo1 3'UTR. In conclusion, these results suggest that Nqo1-AS1 attenuates CS-induced oxidative stress by increasing Nqo1 mRNA stability and upregulating Nqo1 expression, which might serve as a novel approach for the treatment of COPD.

TASK1 and TASK3 in orexin neuron of lateral hypothalamus contribute to respiratory chemoreflex by projecting to nucleus tractus solitarius.

TWIK-related acid-sensitive potassium channels (TASKs)-like current was recorded in orexin neurons in the lateral hypothalamus (LH), which are essential in respiratory chemoreflex. However, the specific mechanism responsible for the pH-sensitivity remains elusive. Thus, we hypothesized that TASKs contribute to respiratory chemoreflex. In the present study, we found that TASK1 and TASK3 were expressed in orexin neurons. Blocking TASKs or microinjecting acid artificial cerebrospinal fluid (ACSF) in the LH stimulated breathing. In contrast, alkaline ACSF inhibited breathing, which was attenuated by blocking TASK1. Damage of orexin neurons attenuated the stimulatory effect on respiration caused by microinjection of acid ACSF (at a pH of 6.5) or TASKs antagonists. The orexinA-positive fiber and orexin type 1 receptor (OX1R) neurons were located in the nucleus tractus solitarius (NTS). The exciting effect of acidosis in the LH on respiration was inhibited by blocking OX1R of the NTS. Taken together, we conclude that orexin neurons sense the extracellular pH change through TASKs and regulate respiration by projecting to the NTS.

Sodium tanshinone IIA sulfonate protects against acute exacerbation of cigarette smoke-induced chronic obstructive pulmonary disease in mice.

Exacerbation of chronic obstructive pulmonary disease (COPD) is characterized by acute airway inflammation and mucus hypersecretion, which is by far the most costly aspect of its management. Thus, it is essential to develop therapeutics with low side effects for CODP exacerbation. Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA isolated as the major active component of Chinese herbal medicine Danshen. Although it possesses anti-inflammatory, anti-oxidative and anti-apoptotic properties, it remains unknown whether STS protects against COPD exacerbation. In this study, we challenged cigarette smoke (CS)-exposed mice with lipopolysaccharide (LPS), and then treated these mice with STS. We found that STS significantly ameliorated pulmonary inflammatory responses, mucus hypersecretion and lung function decline in CS-exposed mice challenged with LPS. STS treatment also significantly attenuated increased IL-6 and IL-8 releases from cigarette smoke extract (CSE)-treated human bronchial epithelial cells (16HBE) challenged with LPS. Mechanistically, STS reduced activation of ERK1/2 and NF-κB in lungs of CS-exposed mice and CSE-treated 16HBE cells challenged with LPS. Taken together, STS protects against acute exacerbation of CS-induced lung injury, which provides a promising and potential therapeutic avenue to halt acute exacerbation of COPD.

Hydrogen sulfide attenuates cigarette smoke-induced airway remodeling by upregulating SIRT1 signaling pathway.

Airway remodeling is one of the characteristics for chronic obstructive pulmonary disease (COPD). The mechanism underlying airway remodeling is associated with epithelial-mesenchymal transition (EMT) in the small airways of smokers and patients with COPD. Sirtuin 1 (SIRT1) is able to reduce oxidative stress, and to modulate EMT. Here, we investigated the effects and mechanisms of hydrogen sulfide (H2S) on pulmonary EMT in vitro and in vivo. We found that H2S donor NaHS inhibited cigarette smoke (CS)-induced airway remodeling, EMT and collagen deposition in mouse lungs. In human bronchial epithelial 16HBE cells, NaHS treatment also reduced CS extract (CSE)-induced EMT, collagen deposition and oxidative stress. Mechanistically, NaHS upregulated SIRT1 expression, but inhibited activation of TGF-ß1/Smad3 signaling in vivo and in vitro. SIRT1 inhibition by a specific inhibitor EX527 significantly attenuated or abolished the ability of NaHS to reverse the CSE-induced oxidative stress. SIRT1 inhibition also abolished the protection of NaHS against CSE-induced EMT. Moreover, SIRT1 activation attenuated CSE-induced EMT by modifying TGF-ß1-mediated Smad3 transactivation. In conclusion, H2S prevented CS-induced airway remodeling in mice by reversing oxidative stress and EMT, which was partially ameliorated by SIRT1 activation. These findings suggest that H2S may have therapeutic potential for the prevention and treatment of COPD.

Hydrogen sulfide inhibits cigarette smoke-induced inflammation and injury in alveolar epithelial cells by suppressing PHD2/HIF-1α/MAPK signaling pathway.

Chronic obstructive pulmonary fibrosis (COPD) is a chronic and fatal lung disease with few treatment options. Sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), was found to alleviate cigarette smoke (CS)-induced emphysema in mice, however, the underlying mechanisms have not yet been clarified. In this study, we investigated its effects on COPD in a CS-induced mouse model in vivo and in cigarette smoke extract (CSE)-stimulated alveolar epithelial A549 cells in vitro. The results showed that NaHS not only relieved emphysema, but also improved pulmonary function in CS-exposed mice. NaHS significantly increased the expressions of tight junction proteins (i.e., ZO-1, Occludin and claudin-1), and reduced apoptosis and secretion of pro-inflammatory cytokines (i.e., TNF-α, IL-6 and IL-1ß) in CS-exposed mouse lungs and CSE-incubated A549 cells, indicating H2S inhibits CS-induced inflammation, injury and apoptosis in alveolar epithelial cells. NaHS also upregulated prolyl hydroxylase (PHD)2, and suppressed hypoxia-inducible factor (HIF)-1α expression in vivo and in vitro, suggesting H2S inhibits CS-induced activation of PHD2/HIF-1α axis. Moreover, NaHS inhibited CS-induced phosphorylation of ERK, JNK and p38 MAPK in vivo and in vitro, and treatment with their inhibitors reversed CSE-induced ZO-1 expression and inflammation in A549 cells. These results suggest that NaHS may prevent emphysema via the suppression of PHD2/HIF-1α/MAPK signaling pathway, and subsequently inhibition of inflammation, epithelial cell injury and apoptosis, and may be a novel strategy for the treatment of COPD.

Hydrogen sulfide attenuates mitochondrial dysfunction-induced cellular senescence and apoptosis in alveolar epithelial cells by upregulating sirtuin 1.

Hydrogen sulfide (H2S), an endogenous gaseous signal molecule, regulates many pathologies related to aging. Sirtuin 1 (SIRT1) has been shown to protect against mitochondrial dysfunction and other pathological processes, including premature senescence. This study was aimed to investigate whether and how H2S attenuates senescence and apoptosis of alveolar epithelial cells via a SIRT1-dependent mechanism. Our results showed that treatment with sodium hydrosulfide (NaHS), a donor of H2S, attenuated cigarette smoke extract (CSE)-induced oxidative stress, mitochondrial dysfunction, cellular senescence and apoptosis in A549 cells. This was associated with SIRT1 upregulation. SIRT1 activation by a pharmacological activator, SRT1720, attenuated CSE-induced oxidative stress and mitochondrial dysfunction in A549 cells. While SIRT1 inhibition by EX 527 or silencing by siRNA transfection significantly attenuated or abolished the ability of NaHS to reverse the CSE-induced oxidative stress, mitochondrial dysfunction and the imbalance of mitochondrial fusion and fission. Also, SIRT1 inhibition or silencing abolished the protection of NaHS against CSE-induced cellular senescence and apoptosis. In conclusion, H2S attenuates CSE-induced cellular senescence and apoptosis by improving mitochondrial function and reducing oxidative stress in alveolar epithelial cells in a SIRT1-dependent manner. These findings provide novel mechanisms underlying the protection of H2S against cigarette smoke-induced COPD.

TASK1 and TASK3 Are Coexpressed With ASIC1 in the Ventrolateral Medulla and Contribute to Central Chemoreception in Rats.

The ventrolateral medulla (VLM), including the lateral paragigantocellular nucleus (LPGi) and rostral VLM (RVLM), is commonly considered to be a chemosensitive region. However, the specific mechanism of chemoreception in the VLM remains elusive. Acid-sensing ion channels (ASICs), a family of voltage-independent proton-gated cation channels, can be activated by an external pH decrease to cause Na+ entry and induce neuronal excitability. TWIK-related acid-sensitive potassium channels (TASKs) are members of another group of pH-sensitive channels; in contrast to AISICs, they can be stimulated by pH increases and are inhibited by pH decreases in the physiological range. Our previous study demonstrated that ASICs take part in chemoreception. The aims of this study are to explore whether TASKs participate in the acid sensitivity of neurons in the VLM, thereby cooperating with ASICs. Our research demonstrated that TASKs, including TASK1 and TASK3, are colocalized with ASIC1 in VLM neurons. Blocking TASKs by microinjection of the non-selective TASK antagonist bupivacaine (BUP), specific TASK1 antagonist anandamide (AEA) or specific TASK3 antagonist ruthenium red (RR) into the VLM increased the integrated phrenic nerve discharge (iPND), shortened the inspiratory time (Ti) and enhanced the respiratory drive (iPND/Ti). In addition, microinjection of artificial cerebrospinal fluid (ACSF) at a pH of 7.0 or 6.5 prolonged Ti, increased iPND and enhanced respiratory drive, which were inhibited by the ASIC antagonist amiloride (AMI). By contrast, microinjection of alkaline ACSF decreased iPND and respiratory drive, which were inhibited by AEA. Taken together, our data suggest that TASK1 and TASK3 are coexpressed with ASIC1 in the VLM. Moreover, TASK1 and TASK3 contribute to the central regulation of breathing by coordinating with each other to perceive local pH changes; these results indicate a novel chemosensitive mechanism of the VLM.

Endobronchial anthracofibrosis: possibly a new indication of aggressive treatment for active endobronchial tuberculosis.

Anthracofibrosis, which was defined as a luminal narrowing associated with overlying anthracotic mucosa on bronchoscopy, has been infrequently reported. Recently, we have identified a case of patient who had a history of pulmonary tuberculosis (TB), manifested left main bronchial stenosis and hyperpigmentation. Despite repeated and multiple cryotherapy, the condition was still progressing. Given to the potential relationship between active endobronchial tuberculosis (EBTB) and anthracofibrosis, the patient received a diagnostic anti-tuberculosis (anti-TB) treatment due to initial failed cryotherapy, resulting in improvement of hyperpigmentation and stenosis of the left main bronchus. Eventually, the patient recovered well with regular anti-TB combined with intermittent cryotherapy. Our study suggests that even without etiological evidence, there might be an indication of therapeutic trial of anti-TB medication in case of repeated bronchial stenosis due to anthracofibrosis in patients with past history of TB and other causes are excluded. Yet, the recommendation of aggressive treatment should reply on the effect of diagnostic treatment and further research.

Hydrogen gas inhalation protects against cigarette smoke-induced COPD development in mice.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a chronic lung disease with limited treatment options. Hydrogen (H2) has been shown to be anti-oxidative and anti-inflammatory. This study aimed to evaluate the beneficial effects of H2 inhalation on COPD development in mice. METHODS: A COPD mouse model was established in male C57BL mice by cigarette smoke (CS) exposure. The H2 intervention was administered by atomisation inhalation. Lung functions were assessed by using Buxco lung function measurement system. The inflammatory cells were counted and the levels of IL-6 and KC in BALF were assayed with ELISA. The lung tissue was subjected to H&E or PAS or Masson's trichrome stain. Furthermore, 16HBE cells were used to evaluate the effects of H2 on signaling change caused by hydrogen peroxide (H2O2). H2O2 was used to treat 16HBE cells with or without H2 pretreatment. The IL-6 and IL-8 levels in cell culture medium were measured. The levels of phosphorylated ERK1/2 and nucleic NF-κB in lungs and 16HBE cells were determined. RESULTS: H2 ameliorated CS-induced lung function decline, emphysema, inflammatory cell infiltration, small-airway remodelling, goblet-cell hyperplasia in tracheal epithelium and activated ERK1/2 and NF-κB in mouse lung. In 16HBE airway cells, H2O2 increased IL-6 and IL-8 secretion in conjunction with ERK1/2 and NF-κB activation. These changes were reduced by H2 treatment. CONCLUSIONS: These findings demonstrated that H2 inhalation could inhibit CS-induced COPD development in mice, which is associated with reduced ERK1/2 and NF-κB-dependent inflammatory responses.

Sodium Tanshinone IIA Sulfonate Decreases Cigarette Smoke-Induced Inflammation and Oxidative Stress via Blocking the Activation of MAPK/HIF-1α Signaling Pathway.

Aberrant activation of hypoxia-inducible factor (HIF)-1α is frequently encountered and promotes oxidative stress and inflammation in chronic obstructive pulmonary disease (COPD). The present study investigated whether sodium tanshinone IIA sulfonate (STS), a water-soluble derivative of tanshinone IIA, can mediate its effect through inhibiting HIF-1α-induced oxidative stress and inflammation in cigarette smoke (CS)-induced COPD in mice. Here, we found that STS improved pulmonary function, ameliorated emphysema and decreased the infiltration of inflammatory cells in the lungs of CS-exposed mice. STS reduced CS- and cigarette smoke extract (CSE)-induced upregulation of tumor necrosis factor (TNF)-α and interleukin (IL)-1ß in the lungs and macrophages. STS also inhibited CSE-induced reactive oxygen species (ROS) production, as well as the upregulation of heme oxygenase (HO)-1, NOX1 and matrix metalloproteinase (MMP)-9 in macrophages. In addition, STS suppressed HIF-1α expression in vivo and in vitro, and pretreatment with HIF-1α siRNA reduced CSE-induced elevation of TNF-α, IL-1ß, and HO-1 content in the macrophages. Moreover, we found that STS inhibited CSE-induced the phosphorylation of ERK, p38 MAPK and JNK in macrophages, and inhibition of these signaling molecules significantly repressed CSE-induced HIF-1α expression. It indicated that STS inhibits CSE-induced HIF-1α expression likely by blocking MAPK signaling. Furthermore, STS also promoted HIF-1α protein degradation in CSE-stimulated macrophages. Taken together, these results suggest that STS prevents COPD development possibly through the inhibition of HIF-1α signaling, and may be a novel strategy for the treatment of COPD.

Two-stage study of lung cancer risk modification by a functional variant in the 3'-untranslated region of SMAD5 based on the bone morphogenetic protein pathway.

Increasing evidence supports a key role for the bone morphogenetic protein (BMP) signaling pathway in lung vasculogenesis and angiogenesis. Genetic variations in BMP genes have been found to be correlated with cancer risk. In particular, the mutation in the 3'-untranslated region of BMPs may significantly affect gene function, leading to cancer susceptibility. The aim of the present study was to determine whether genetic variations in the components of the BMP family are associated with lung cancer risk. A total of 314 tag single-nucleotide polymorphisms were identified in 18 genes, which are considered to either compose or regulate BMPs, and their association with lung cancer risk was evaluated in a two-stage case-control study with 4,680 cases and controls. A consistently significant association of SMAD5 rs12719482 with elevated lung cancer risk was observed in the three types of sources of populations (adjusted additive model in the combined population: Odds ratio=1.32, 95% confidence interval: 1.16-1.51). The lung cancer risk statistically significantly increased with the increasing number of variant alleles of SMAD5 rs12719482 in a dose-dependent pattern (P for trend=4.9×10-5). Consistent evidence was identified for a significant interaction between the rs12719482 and cigarette smoking, performed as either a continuous or discrete variable. These findings indicated that SMAD5 rs12719482 may be a possible candidate marker for susceptibility to lung cancer in the Chinese population.

Tanshinone IIA sulfonate protects against cigarette smoke-induced COPD and down-regulation of CFTR in mice.

Chronic obstructive pulmonary disease (COPD) is a chronic lung disease characterized by abnormal inflammation, persistent and progressive lung function decline. The anti-inflammatory actions of tanshinone IIA, which is the most important active component from Chinese herbal medicine Danshen, have been well studied. However, it remains unknown whether sodium tanshinone IIA sulfonate (STS) protects against the development of COPD. Here we found that STS inhalation (5 mg/kg, 30 min per session, twice a day) significantly attenuated lung function decline, airspace enlargement, mucus production, bronchial collagen deposition, inflammatory responses and oxidative stress caused by cigarette smoke (CS) and lipopolysaccharide (LPS) exposures in mice. Moreover, treatment with STS (10 µg/ml) reduced CS extract (CSE)-induced IL-6 and IL-8 secretion in human bronchial epithelial (16HBE) cells. The anti-inflammatory actions of STS were associated with inhibition of ERK1/2 and NF-κB activations. Interestingly, STS inhibited CS-induced reduction of cystic fibrosis transmembrane conductance regulator (CFTR) in mouse lungs and in 16HBE cells. Treatment with a specific CFTR inhibitor CFTR-Inh172 augmented CSE-induced ERK1/2 and NF-κB-dependent inflammatory responses, but abolished the inhibitory action of STS on IL-6 and IL-8 secretion in 16HBE cells. These results demonstrate that CS-induced COPD and down-regulation of CFTR are prevented by STS.

Upregulation of AT1 Receptor Mediates a Pressor Effect Through ROS-SAPK/JNK Signaling in Glutamatergic Neurons of Rostral Ventrolateral Medulla in Rats With Stress-Induced Hypertension.

The present study examined whether angiotensin II (Ang II) mediates the pressor effect through nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-derived reactive oxygen species (ROS)-mitogen-activated protein kinase (MAPK) signaling in the glutamatergic neurons of the rostral ventrolateral medulla (RVLM) in stress-induced hypertensive rats (SIHR). The SIHR model was established using electric foot-shocks combined with noises for 15 days. We observed that Ang II type 1 receptor (AT1R) and the glutamatergic neurons co-localized in the RVLM of SIHR. Furthermore, glutamate levels in the intermediolateral column of the spinal cord were higher in SIHR than in controls. Microinjection of Ang II into the RVLM of SIHR activated stress-activated protein kinase/Jun N-terminal kinase (SAPK/JNK), extracellular signal-regulated protein kinase (ERK) 1/2, and p38MAPK. Compared with controls, the activation of SAPK/JNK, ERK1/2, p38MAPK, and ROS in the RVLM were higher in SIHR, an effect that was blocked by an NADPH oxidase inhibitor (apocynin) and an AT1R antagonist (candesartan). RVLM microinjection of apocynin or a SAPK/JNK inhibitor (SP600125), but not an ERK1/2 inhibitor (U0126) or a p38MAPK inhibitor (SB203580), decreased AT1R mRNA and mean arterial blood pressure (MABP) in SIHR. The increase of AT1R protein expression and MABP was inhibited by intracerebroventricular infusion (ICV), for 14 days, of SP600125, but not U0126 or SB203580 in SIHR. We conclude that Ang II modulates the pressor effect through AT1R-dependent ROS-SAPK/JNK signaling in glutamatergic neurons in the RVLM of SIHR.