New evidence for a role of DANCR in cancers: a comprehensive review.

Cancer remains a leading cause of mortality and poses a substantial threat to public health. Studies have revealed that Long noncoding RNA DANCR is a cytoplasmic lncRNA whose aberrant expression plays a pivotal role in various cancer types. Within tumour biology, DANCR exerts regulatory control over crucial processes such as proliferation, invasion, metastasis, angiogenesis, inflammatory responses, cellular energy metabolism reprogramming, and apoptosis. By acting as a competitive endogenous RNA for miRNAs and by interacting with proteins and mRNAs at the molecular level, DANCR contributes significantly to cancer progression. Elevated DANCR levels have also been linked to heightened resistance to anticancer drugs. Moreover, the detection of circulating DANCR holds promise as a valuable biomarker for aiding in the clinical differentiation of different cancer types. This article offers a comprehensive review and elucidation of the primary functions and molecular mechanisms through which DANCR influences tumours.

Expression and regulation of HIF-1a in hypoxic pulmonary hypertension: Focus on pathological mechanism and Pharmacological Treatment.

Hypoxia inducible factor-1(HIF-1), a heterodimeric transcription factor, is composed of two subunits (HIF-1α and HIF-1ß). It is considered as an important transcription factor for regulating oxygen changes in hypoxic environment, which can regulate the expression of various hypoxia-related target genes and play a role in acute and chronic hypoxia pulmonary vascular reactions. In this paper, the function and mechanism of HIF-1a expression and regulation in hypoxic pulmonary hypertension (HPH) were reviewed, and current candidate schemes for treating pulmonary hypertension by using HIF-1a as the target were introduced, so as to provide reference for studying the pathogenesis of HPH and screening effective treatment methods.

α1-Antitrypsin alleviates inflammation and oxidative stress by suppressing autophagy in asthma.

BACKGROUND: Asthma is considered an incurable disease, although many advances have been made in asthma treatments in recent years. Therefore, elucidating the pathological mechanisms and seeking novel and effective therapeutic strategies for asthma are urgently needed. METHODS: Airway resistance was measured by whole-body plethysmography. H&E staining was used to observe the morphological changes in the lung. Oxidative stress was assessed by measuring the levels of MDA, CAT and SOD. Gene expression was analysed by western blotting and RT-qPCR. ELISA was used to analyse the concentrations of IL-4, IL-5 and IFN-γ. RESULTS: In the present study, we successfully established in vivo and in vitro asthma models. OVA administration led to elevated lung resistance, cell counts in BALF, and cytokine secretion, impaired airway structure and enhanced oxidative stress and autophagy in a mouse model of asthma, while IL-13 induced inflammation, oxidative stress and autophagy in BEAS-2B cells. A1AT reduced lung resistance and cell counts in BALF and suppressed inflammation, oxidative stress and autophagy in a mouse model of asthma and IL-13-induced BEAS-2B cells. Mechanistic investigations revealed that autophagy activation compromised the protective effect of A1AT on IL-13-induced BEAS-2B cells. Further mechanistic studies revealed that A1AT alleviated inflammation and oxidative stress by inhibiting autophagy in the context of asthma. CONCLUSION: We demonstrated that A1AT could alleviate inflammation and oxidative stress by suppressing autophagy in the context of asthma and thus ameliorate asthma. Our study revealed novel pathological mechanisms and provided novel potential therapeutic targets for asthma treatment.

Endoplasmic Reticulum Stress Induces HRD1 to Protect Alveolar Type II Epithelial Cells from Apoptosis Induced by Cigarette Smoke Extract.

BACKGROUND/AIMS: Cigarette smoking is a major risk factor of chronic obstructive pulmonary disease. This study aimed to examine the effects of cigarette smoke extract (CSE) on alveolar type II epithelial cells (AECII) and investigate the underlying mechanism. METHODS: Primary AECII were isolated from rat lung tissues and exposed to CSE. Apoptosis was detected by flow cytometry. Protein expression was detected by Western blot analysis. RESULTS: Primary rat AECII maintained morphological and physiological characteristic after 3 passages. CSE increased the expression of ER specific pro-apoptosis factors CHOP and caspase 12, and the phosphorylation of JNK in AECII. CSE activated ER stress signaling and increased the phosphorylation of PERK, eIF2α and IRE1. Furthermore, CSE induced the expression of Hrd1, a key factor of ER-associated degradation, in AECII. Knockdown of Hrd1 led to more than 2 fold increase of apoptosis, while overexpression of Hrd1 attenuated CSE induced apoptosis of AECII. CONCLUSIONS: Our results suggest that ER stress induces HRD1 to protect alveolar type II epithelial cells from apoptosis induced by CSE.

[Allergens-induced sensitization alters airway epithelial adhesion molecules expression in mice].

To explore the relationship between the epithelial adhesion molecules and immune responses of airway epithelium, we observed the expression of integrin ß4 and intercellular adhesion molecule-1 (ICAM-1) in the mice airway epithelium after sensitization with allergens. BALB/c mice were sensitized with intraperitoneal injection of ovalbumin (OVA) or house dust mite (HDM) and then developed airway hyper-responsiveness as determined by barometric whole-body plethysmography. Both OVA and HDM sensitization led to increases of the number of peripheral leukocytes as well as inflammatory cells infiltration in lungs. OVA sensitized mice showed more severe inflammatory cells infiltration than HDM sensitized mice. Immunohistochemistry analysis of mice lung tissues revealed that sensitization with both allergens also led to a decrease of integrin ß4 expression and an increase of ICAM-1 expression in airway epithelia. OVA sensitized mice showed a more significant increase of ICAM-1 expression compared with HDM sensitized mice. siRNA mediated silencing of integrin ß4 gene in 16HBE cells resulted in an up-regulation of ICAM-1 expression. Our results indicate a possible role of airway epithelial adhesion molecules in allergen-induced airway immune responses.

Role of mitophagy in pulmonary hypertension: Targeting the mechanism and pharmacological intervention.

Mitophagy, a crucial pathway in eukaryotic cells, selectively eliminates dysfunctional mitochondria, thereby maintaining cellular homeostasis via mitochondrial quality control. Pulmonary hypertension (PH) refers to a pathological condition where pulmonary arterial pressure is abnormally elevated due to various reasons, and the underlying pathogenesis remains elusive. This article examines the molecular mechanisms underlying mitophagy, emphasizing its role in PH and the progress in elucidating related molecular signaling pathways. Additionally, it highlights current drug regulatory pathways, aiming to provide novel insights into the prevention and treatment of pulmonary hypertension.

[Sublingual gland amyloidosis causing obstructive sleep apnea hypopnea syndrome: a case report and review of the literatures].

OBJECTIVE: To improve the understanding of sublingual gland amyloidosis causing obstructive sleep apnea hypopnea syndrome(OSAHS). METHODS: A case of sublingual gland amyloidosis causing OSAHS diagnosed in april 2012 was reported and the related literatures were reviewed. The literature review was carried out respectively with "amyloidosis, sublingual gland, obstructive sleep apnea hypopnea syndrome", as the search terms in Wanfang Data and PubMed by November 2012. RESULTS: A case of 74 year-old male patient was admitted to the hospital because of snoring for 5 years, sleep apnea for 1 year and arousal for 1 month. After admission, polysomnography showed severe OSAHS, physical examination showed redundant the sublingual gland. Enhanced CT scanning showed soft tissue masses at the sublingual gland. Abdominal B ultrasonic and CT also showed a spaces-occupying lesion in the left retroperitoneal. B-guided core needle biopsy was performed in the left retroperitoneal. Pathology report showed amyloidosis. Subsequently, sublingual gland mass resection was performed. Pathology report after operation showed amyloid deposits staining with Congo red, which gives it a characteristic green birefringence in polarised light. Accordingly, it was diagnosed as sublingual gland amyloidosis. The symptoms of snore and sleep apnea were disappeared after operation.So far, there was no local recurrence with 10 months follow-up. A total of 3 literatures were received in Wanfang Data, including 2 of macroglossia amyloidosis causeing OSAHS case report and one of retrospective study. There were no reports about sublingual gland amyloidosis in Wanfang Data. A total of 5 literatures were received in Pubmed, including 2 of sublingual gland amyloidosis case report, 2 of macroglossia amyloidosis causeing OSAHS case report and one of retrospective study. However, there were no reports about sublingual gland amyloidosis causing OSAHS. CONCLUSIONS: Amyloidosis rarely occurred in the sublingual gland and is easy to be misdiagnosed and missed diagnosed, which can causing severe OSAHS. To make a definite diagnosis, histopathology and staining with Congo red are needed and a characteristic green birefringence in polarised light is a reliable marker for diagnosis. After sublingual gland mass resection, the patient had good prognosis.

Celastrol: The new dawn in the treatment of vascular remodeling diseases.

Evidence is mounting that abnormal vascular remodeling leads to many cardiovascular diseases (CVDs). This suggests that vascular remodeling can be a crucial target for the prevention and treatment of CVDs. Recently, celastrol, an active ingredient of the broadly used Chinese herb Tripterygium wilfordii Hook F, has attracted extensive interest for its proven potential to improve vascular remodeling. Substantial evidence has shown that celastrol improves vascular remodeling by ameliorating inflammation, hyperproliferation, and migration of vascular smooth muscle cells, vascular calcification, endothelial dysfunction, extracellular matrix remodeling, and angiogenesis. Moreover, numerous reports have proven the positive effects of celastrol and its therapeutic promise in treating vascular remodeling diseases such as hypertension, atherosclerosis, and pulmonary artery hypertension. The present review summarizes and discusses the molecular mechanism of celastrol regulating vascular remodeling and provides preclinical proof for future clinical applications of celastrol.

A Lipid Perspective on Regulated Pyroptosis.

Pyroptosis is a novel pro-inflammatory cell programmed death dependent on Gasdermin (GSMD) family-mediated membrane pore formation and subsequent cell lysis, accompanied by the release of inflammatory factors and expanding inflammation in multiple tissues. All of these processes have impacts on a variety of metabolic disorders. Dysregulation of lipid metabolism is one of the most prominent metabolic alterations in many diseases, including the liver, cardiovascular system, and autoimmune diseases. Lipid metabolism produces many bioactive lipid molecules, which are important triggers and endogenous regulators of pyroptosis. Bioactive lipid molecules promote pyroptosis through intrinsic pathways involving reactive oxygen species (ROS) production, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, lysosomal disruption, and the expression of related molecules. Pyroptosis can also be regulated during the processes of lipid metabolism, including lipid uptake and transport, de novo synthesis, lipid storage, and lipid peroxidation. Taken together, understanding the correlation between lipid molecules such as cholesterol and fatty acids and pyroptosis during metabolic processes can help to gain insight into the pathogenesis of many diseases and develop effective strategies from the perspective of pyroptosis.

[Effects of feixin decoction on the contents of hypoxia-inducible factor-1alpha and vascular endothelial growth factor in the rat model of hypoxic pulmonary hypertension].

OBJECTIVE: To explore the effects of Feixin Decoction (FXD) on the hypoxia-inducible factor-1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) in the rat model of hypoxic pulmonary hypertension (HPH), and to study its mechanisms for treating HPH. METHODS: Forty healthy male SD rats were randomly divided into four groups, i. e., the normal control group, the HPH model group, the FXD group, and the Nifedipine group, 10 rats in each group. The HPH rat model was prepared using normal pressure intermittent hypoxia method. Except the normal control group, rats in the rest groups were fed in a self-made hypoxic plexiglass cabin, with the poor oxygen condition for 8 h daily for 14 successive days. Then the distilled water (at 30 mL/kg) was given by gastrogavage to rats in the normal control group and the HPH model group. FXD (at 28 g/kg) and Nifedipine (at 20 mg/kg) were given by gastrogavage to rats in the FXD group and the Nifedipine group respectively, once daily, for 14 successive days. Besides, hypoxia was continued for 14 days while medicating. The mean pulmonary artery pressure (mPAP) was detected on the second day after the last medication. The morphology of the pulmonary arteriole was detected. The ratio of pulmonary artery wall area and tube area (WA%) was determined. The protein and mRNA expressions of HIF-1alpha and VEGF were detected using immunohistochemistry and in situ hybridization technique. RESULTS: Compared with the normal control group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly increased in the model group (P < 0.01, P < 0.05). Compared with the HPH model group, mPAP, WA%, and the protein and mRNA expressions of HIF-1alpha and VEGF significantly decreased in the FXD group (P < 0.01, P < 0.05). CONCLUSIONS: FXD down-regulated the expression of VEGF through decreasing the expression of HIF-1alpha. One of its mechanisms for treating HPH might be partially due to reversing the remodeling of pulmonary vascular smooth muscle.

PVAT targets VSMCs to regulate vascular remodelling: angel or demon.

Vascular remodelling refers to abnormal changes in the structure and function of blood vessel walls caused by injury, and is the main pathological basis of cardiovascular diseases such as atherosclerosis, hypertension, and pulmonary hypertension. Among them, the neointimal hyperplasia caused by abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a key role in the pathogenesis of vascular remodelling. Perivascular adipose tissue (PVAT) can release vasoactive substances to target VSMCs and regulate the pathological process of vascular remodelling. Specifically, PVAT can promote the conversion of VSMCs phenotype from contraction to synthesis by secreting visfatin, leptin, and resistin, and participate in the development of vascular remodelling-related diseases. Conversely, it can also inhibit the growth of VSMCs by secreting adiponectin and omentin to prevent neointimal hyperplasia and alleviate vascular remodelling. Therefore, exploring and developing new drugs or other treatments that facilitate the beneficial effects of PVAT on VSMCs is a potential strategy for prevention or treatment of vascular remodelling-related cardiovascular diseases.

CHOP overexpression sensitizes human non-small cell lung cancer cells to cisplatin treatment by Bcl-2/JNK pathway.

C/EBP homologous protein (CHOP), a 29 kDa cellular protein, plays a role in regulating tumor proliferation, differentiation, metabolism, cell death, and in tumor resistance to chemotherapy. Non-small cell lung cancer (NSCLC) is a tumor of the respiratory system and drug resistance is prevalent among NSCLC clinical cell cultures. Herein, our study elucidated the effect of CHOP on NSCLC cells with cisplatin resistance and its mechanism. In a NSCLC cell line with cisplatin-resistance, CHOP expression was decreased, compared with A549 cells. Overexpression of CHOP decreased the cell viability and enhanced cell apoptosis in the cells treated with cisplatin. Expression of CHOP also inhibited the cell proliferation and metastasis. CHOP increased the therapeutic effect of cisplatin on NSCLC cells through the Bcl-2/JNK pathway. In summary, CHOP regulated cisplatin resistance in cells of NSCLC by promoting the expression of apoptotic proteins and inhibiting the Bcl-2/JNK signaling pathway, indicating the antitumor effects of CHOP.

KLF2 regulates neutrophil migration by modulating CXCR1 and CXCR2 in asthma.

Neutrophils are key inflammatory cells in the immunopathogenesis of asthma. Neutrophil migration can be initiated through activation of the CXCR1 and CXCR2 receptors by CXC chemokines, such as IL-8. Although transcription factor KLF2 has been found to maintain T cell migration patterns through repression of several chemokine receptors, whether KLF2 can regulate neutrophil migration via modulation of CXCR1 and CXCR2 is unknown. Here, we aimed to explore the functions of KLF2, CXCR1 and CXCR2 in neutrophil migration in asthma and to establish a regulatory role of KLF2 for CXCR1/2. We demonstrate that with asthma aggravation, the percentages and migration rates of peripheral blood neutrophils gradually increased in asthmatic patients and the guinea pig asthma model. Correspondingly, both the KLF2 mRNA and protein levels in neutrophils were gradually reduced. While CXCR1 and CXCR2 expression was negatively correlated with KLF2. In vitro knockdown of KLF2 dramatically increased the migration of HL-60-drived neutrophil-like cells, which was accompanied by an increase in the CXCR1 and CXCR2 mRNA and protein expression levels. Taken together, our results indicate that decreased KLF2 aggravates asthma progression by promoting neutrophil migration, which is associated with the transcriptional upregulation of CXCR1 and CXCR2. The KLF2 and/or CXCR1/2 expression levels may represent an indicator of asthma severity.

[The expression of capillary hypoxia-induced factor-alpha and pulmonary artery remodeling in chronic obstructive pulmonary disease].

OBJECTIVE: To observe the expression of hypoxia-inducible factor-alpha (HIF-1alpha, HIF-2alpha, HIF-3alpha) and pulmonary vascular remodeling in pulmonary arteries of patients with chronic obstructive pulmonary disease (COPD). METHODS: Pulmonary specimens were obtained from patients undergoing lobectomy for lung cancer, of whom 12 had concurrent COPD and 10 without COPD. Pulmonary vascular remodeling was observed with optical microscope, and HIF-alpha mRNA and protein were detected by in situ hybridization and immunohistochemistry respectively. RESULTS: Vascular remodeling parameters (WT%, WA%) of COPD patients [(24 +/- 3)%, (48 +/- 6)%, respectively] were statistically different from those of the control subjects [(15 +/- 2)%, (39 +/- 4)%, respectively]. Relative quantification of mRNA and protein levels (absorbance, A) showed that HIF-1alpha in COPD group (0.172 +/- 0.011, 0.089 +/- 0.013, respectively) were statistically higher than those of the control subjects (0.103 +/- 0.010, 0.042 +/- 0.010, P < 0.01). Furthermore, they correlated positively with the parameters for vascular remodeling. The mRNA and protein levels of HIF-2alpha in COPD group (0.038 +/- 0.010, 0.077 +/- 0.010, respectively) were significantly lower than those of the control subjects (0.133 +/- 0.017, 0.169 +/- 0.010, respectively, P < 0.01), and correlated negatively with the parameters for vascular remodeling. Regarding HIF-3alpha, only the mRNA level in COPD group (0.077 +/- 0.010) was statistically lower than that of the control subjects (0.088 +/- 0.010) (P < 0.05), and no correlation with vascular remodeling parameters was observed. CONCLUSIONS: Pulmonary vascular remodeling in COPD patients was accompanied by the differential expression of HIF-alpha gene, which may be involved in the process of hypoxic pulmonary vascular remodeling in COPD.

[Expression of mitogen-actived protein kinase, phosphatidylinositol 3-kinase and hypoxia-inducible factor-1alpha in pulmonary arteries of patients with chronic obstructive pulmonary disease].

OBJECTIVE: To investigate the expression of mitogen-actived protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K) and hypoxia-inducible factor-1alpha (HIF-1alpha) in pulmonary artery of chronic obstructive pulmonary disease (COPD), and therefore to explore the possible roles of MAPK, PI3K and HIF-1alpha in the development of hypoxia-induced pulmonary hypertension (HPH). METHODS: Small pulmonary arterial remodeling was observed by morphometric analysis in surgically removed lung tissues from COPD patients and control patients treated for lung tumors. The expression of p-ERK, p-JNK, p-P38, p-PKB and HIF-1alpha in lung tissue was examined by in situ hybridization and immunohistochemistry. RESULTS: Morphometry analysis showed that the ratio of wall area to total area (WA%) and pulmonary artery media thickness (PAMT) were increased in COPD patients [18 +/- 3, (31 +/- 3) microm] than in the control [30 +/- 5, (40 +/- 4) microm, t = 7.58, 6.57, all P < 0.01]. The expression levels of p-ERK protein, p-PKB protein, HIF-1alpha protein and HIF-1alpha mRNA level (absorbance, A) were significantly higher in pulmonary artery walls of COPD patients (0.164 +/- 0.012, 0.113 +/- 0.009, 0.232 +/- 0.008, 0.154 +/- 0.013, respectively) as compared to those of the control (0.062 +/- 0.010, 0.031 +/- 0.011, 0.058 +/- 0.006, 0.052 +/- 0.008, respectively, t = 23.18, 21.03, 62.14, 2.44, all P < 0.01), while p-JNK and p-P38 protein levels in the control group (0.048 +/- 0.013, 0.028 +/- 0.007, respectively) and COPD patients (0.041 +/- 0.012, 0.031 +/- 0.010, respectively, all P > 0.05) were barely positive. The expression of p-ERK, p-PKB and HIF-1alpha were negatively correlated with LA% (r = -0.920 - -0.892, all P < 0.05), and positively correlated with PAMT (r = 0.895 - 0.934, all P < 0.05). CONCLUSION: Differential expression of p-ERK, p-PKB and HIF-1alpha may be involved in the occurrence of HPH in COPD patients.

[Differential expression of the three hypoxia-inducible factor alpha subunits in pulmonary artery of rats with hypoxia-induced pulmonary hypertension].

OBJECTIVE: To differentiate the expression patterns of all hypoxia-inducible factor alpha (HIF-alpha) subunits (HIF-1alpha, HIF-2alpha and HIF-3alpha) in pulmonary artery of rats undergoing systemic hypoxia. METHODS: Forty male healthy wistar rats were assigned randomly to 5 groups, 8 rats per group, then exposed to hypoxia [O2, (10.0 +/- 0.5)%] for 0 d (H(0)), 3 d (H(3)), 7 d (H(7)), 14 d (H(14)) and 21 d (H(21)) respectively, 8 h per day intermittently. Mean pulmonary arterial pressure (mPAP), arterial wall area (WA, microm), pulmonary artery medium thickness (PAMT%) and right ventricle hypertrophy index (RVHI) were measured. HIF-1alpha, HIF-2alpha and HIF-3alpha gene expression were determined by immunohistochemistry, in situ hybridization and Western blot. RESULTS: mPAPs in H(7), H(0) and H(14) groups were [(18.40 +/- 0.40) mm Hg, 1 mm Hg = 0.133 kPa], [(14.40 +/- 0.40) mm Hg] and [(21.20 +/- 0.20) mm Hg], respectively, statistically different when H(7) group was compared with H(0) and H(14) groups (all P < 0.05). Arterial morphology showed that WA%, PAMT and RVHI% in H(7) group were (47.8 +/- 0.8)%, (12.3 +/- 0.5) microm, (24.0 +/- 1.0)%, respectively; in H(0) group were (35.5 +/- 1.3)%, (11.9 +/- 0.6)%, (23.6 +/- 0.5) microm, respectively; in H(21) group were (65.0 +/- 0.7)%, (23.0 +/- 0.8) microm, (27.7 +/- 1.0)%, respectively. When H(7) group was compared with H(0) group, only WA% was statistically different; when H(14) group was compared with H(0) group, all the three parameters were statistically different (P < 0.05). In situ hybridization demonstrated that the mRNA levels (absorbance, A) of HIF-1alpha, HIF-2alpha, and HIF-3alpha in H(14) group were 0.200 +/- 0.020, 0.080 +/- 0.010, 0.170 +/- 0.010, respectively; in H(7) group were 0.050 +/- 0.020, 0.160 +/- 0.020, 0.160 +/- 0.020, respectively; in H(0) group were 0.050 +/- 0.010, 0.140 +/- 0.020, 0.060 +/- 0.010, respectively. When H(7) group was compared with H(0) group, only HIF-3alpha was statistically different; when H(14) group was compared with H(0) group, all the three genes were significantly different (P < 0.05). Immunohistochemistry showed that HIF-1alpha, HIF-2alpha and HIF-3alpha protein levels in H(3) group were 0.200 +/- 0.020, 0.020 +/- 0.010, 0.050 +/- 0.010, respectively; in H(14) group were 0.160 +/- 0.010, 0.100 +/- 0.020, 0.160 +/- 0.010, respectively; in H(7) group were 0.220 +/- 0.020, 0.030 +/- 0.010, 0.180 +/- 0.020, respectively; in H(0) group were 0.050 +/- 0.010, 0.020 +/- 0.010, 0.040 +/- 0.010, respectively. HIF-1alpha in H(3) group, HIF-2alpha in H(14) group, HIF-3alpha in H(7) and H(3) group were statistically different with that of H(0) group (P < 0.05). Protein bands of HIF-alpha subunits in lung tissue, measured by Western blot, showed that HIF-3alpha decreased in H(7) group as compared to H(0) group, but the other two proteins showed a marked increase in H(3) group as compared to H(0) group, and increased further corresponding to the duration of hypoxia and peaked in H(14) group as compared to H(7) group. CONCLUSION: The differential expression of the three HIF-alpha subunits may play a role in the development of hypoxia-induced pulmonary hypertension.

[Reciprocal regulation between hypoxia-inducible factor-1alpha and its prolyl hydroxylases in hypoxic pulmonary hypertension rats].

OBJECTIVE: To investigate the interaction between hypoxia-inducible factors-1alpha subunit (HIF-1alpha) and its three prolyl hydroxylases (PHD1, PHD2 and PHD3) during the development of rat hypoxic pulmonary hypertension. METHODS: Forty male SD rats were randomly divided into 5 groups and exposed to normoxia (C group) or exposed to hypoxia for 3, 7, 14 or 21 d (H(3), H(7), H(14), H(21) group), respectively. Mean pulmonary arterial pressure (mPAP), vessel morphometry and right ventricle hypertrophy index (RVHI) were measured. Reverse transcriptase-polymerase chain reaction (RT-PCR) and in situ hybridization were used to determine the expression of mRNA. Immunohistochemistry and Western blot were used to determine the expression of mRNA. RESULTS: The level of mPAP [(21.7 +/- 2.4) mm Hg, 1 mm Hg = 0.133 kPa], the ratio of vascular wall thickness to external diameter [WA%, (43.9 +/- 5.3)%] and pulmonary artery media thickness [PAMT, (10.0 +/- 0.7) microm] were significantly higher in H(7) group than those in C group [(16.6 +/- 1.6) mm Hg, (36.3 +/- 4.8)% and (8.5 +/- 1.3) microm respectively, q value were 5.591, 4.082, 2.929, respectively, all P < 0.05]. These parameters reached a high level and remained stable on H(14) group, and RVHI was significantly higher in H(14) group [(27.6 +/- 1.4)%] than in C group [(23.6 +/- 2.9)%, q = 5.817, P < 0.05]. HIF-1alpha protein was barely positive in C group (0.080 +/- 0.009), but markedly up-regulated in H(3) group (0.196 +/- 0.018, compared with C group q = 18.864, P < 0.05), reaching its peak in H(7) group (0.203 +/- 0.022), and then declined slightly in H(14) and H(21) group. HIF-1alpha mRNA increased marginally in H(14) group (0.176 +/- 0.019, compared with C group q = 5.401, P < 0.05, 0.139 +/- 0.017). PHD1 and PHD2 mRNA (0.260 +/- 0.031, 0.196 +/- 0.023) and protein (0.244 +/- 0.030, 0.205 +/- 0.025) were positive in C group. PHD2 mRNA and protein were up-regulated in H(3) group (0.246 +/- 0.023, 0.235 +/- 0.025, compared with C group q value was 5.268, 3.046, respectively, all P < 0.05), reaching its peak in H(14) group whereas PHD1 protein declined in H(14) group (0.210 +/- 0.023, compared with C group q = 3.885, P < 0.05) without significant mRNA change. PHD3 mRNA and protein were detected at low level in C group (0.110 +/- 0.013, 0.153 +/- 0.019), but markedly up-regulated in H(3) group (0.259 +/- 0.024, compared with C group q = 15.831, P < 0.05), and then PHD3 mRNA remained at high level while PHD3 protein declined in H(14) and H(21) group (0.206 +/- 0.025, 0.189 +/- 0.019, compared with H(7) group q value was 6.441, 8.526, respectively, all P < 0.05). Linear correlation analysis showed that HIF-1alpha mRNA and protein were positively correlated with mPAP. There was a positive correlation between HIF-1alpha protein and PHD2, PHD3 mRNA (r value was 0.580, 0.690, respectively, all P value was 0.000) but a negative correlation between HIF-1alpha protein and PHD2 protein (r = -0.704, P < 0.05). CONCLUSIONS: HIF-1alpha was regulated mainly at the protein level during the development of hypoxic pulmonary hypertension. PHD2 and PHD3 are inducible by hypoxia, possibly via elevated HIF-1alpha, suggesting that a hypoxic up-regulation of PHD acts via feedback mechanism to attenuate hypoxia induced responses. PHD may also be regulated by posttranscriptional mechanisms.

[The relationship between the polymorphism of glutamate cysteine ligase modulatory subunit gene and the susceptibility to chronic obstructive pulmonary disease].

OBJECTIVE: To investigate whether glutamate cysteine ligase modulatory (GCLM) subunit gene polymorphism is associated with susceptibility to chronic obstructive pulmonary disease (COPD), and to study the relationship between polymorphism of GCLM gene with plasma gamma-glutamylcysteine synthetase (gamma-GCS) activity. METHODS: Blood samples of 104 stable phase COPD smokers (COPD group), 124 healthy smokers (C group) and 132 healthy never-smokers (H group) were collected, and then the genotypes of GCLM -588C/T and GCLM -23C/T polymorphism sites were detected by polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis (RFLP). The plasma gamma-GCS activity was measured by coupled enzyme procedure. RESULTS: (1) The distribution of -588CC, -588CT, -588TT genotypes were corresponding to -23GG, -23GT, -23TT respectively in all of the individuals. (2) The frequencies of -588CC genotype and -588 C allele were significantly lower in COPD group (62.3% and 79.2%) than in C group (84.7% and 91.9%) and H group (78.8% and 89.0%, P < 0.01). (3) In smokers, GCLM -588 T allele carried a higher risk to COPD, the odds ratio (OR value) to C allele was 3.0, and with a 95% confidence interval 1.7 - 5.3. (4) The plasma gamma-GCS activity was increased in C group [(282 +/- 58) U/mg.prot] and COPD group [(224 +/- 54) U/mg.prot] as compared with H group [(157 +/- 26) U/mg.prot, P < 0.01], and were higher in healthy smokers than in COPD smokers (P < 0.01). (5) The smokers with -588CC genotype had higher gamma-GCS activity than CT or TT genotype [(292 +/- 54), (225 +/- 45) U/mg.prot, P < 0.01 in C group and (245 +/- 52), (188 +/- 36) U/mg.prot, P < 0.01 in COPD group], but the difference did not exist in H group [(158 +/- 27), (153 +/- 25) U/mg.prot, P > 0.05]. CONCLUSION: The polymorphism of GCLM -588C/T and -23G/T sites were associated with susceptibility to COPD, and were associated with plasma gamma-GCS activity.

[Mitogen-activated protein kinase regulated hypoxia-inducible factor 1alpha in hypoxia-induced pulmonary hypertension in rats].

OBJECTIVE: To investigate the dynamic expression of hypoxia-inducible factor 1alpha (HIF-1alpha) and mitogen-activated protein kinase (MAPK) in pulmonary arteries of rats with hypoxia-induced pulmonary hypertension. METHODS: Forty male adult Wistar rats were randomly divided into five groups:a control group (C group) and groups with hypoxia for 3, 7, 14 and 21 days (H(3), H(7), H(14) and H(21) group), eight rats per group. Mean pulmonary pressure (mPAP), right ventrical hypertrophy index (RVHI) and vessel morphometry were measured. The levels of HIF-1alpha mRNA expression in lung tissue was measured by in site hybridization (ISH). The protein expression of HIF-1alpha and p-ERK, p-JNK, p-P38 were observed by immunohistochemistry or Western blot. RESULTS: The level of mPAP [(23.5 +/- 1.8) mm Hg], the ratio of vascular wall thickness to external diameter [WT, (45.5 +/- 3.1)%] and the ratio of vascular wall area to the total area [LA, (54.7 +/- 3.2)%] were significantly higher in H(7) group than those in C group [(16.2 +/- 2.0) mm Hg, (36.8 +/- 2.5)% and (63.2 +/- 2.5)% respectively, all P < 0.05]. These parameters reached a high level and remained stable on H(14) group, RVHI was significantly higher [(26.9 +/- 1.3)%] on H(14) group than in C group [(23.0 +/- 1.5)%, P < 0.05]. Expression of p-ERK protein in C group was barely positive, but was up-regulated in pulmonary arterial tunica intima and tunica media of all hypoxia rats. Expression of p-JNK and p-P38 in C group and hypoxia groups were barely positive. Expression of HIF-1alpha protein in C group was barely positive, but was up-regulated in pulmonary arterial tunica intima of all hypoxic rats. In pulmonary arterial tunica media, the levels of HIF-1alpha protein was markedly up-regulated in H(3) group (0.209 +/- 0.009, P < 0.05), reaching its peak at H(7) group (0.232 +/- 0.008, P < 0.05), then tended to decline in H(14) group and H(21) group. HIF-1alpha mRNA staining was barely positive in C group, H(3) group and H(7) group, but began to increase significantly at H(14) group (0.305 +/- 0.104, P < 0.05), then remained stable in pulmonary arterial tunica intima. Linear correlation analysis showed that p-ERK, HIF-1alpha mRNA and mPAP were correlated with vessel morphometry and RVHI (P < 0.01); p-ERK was positively correlated with HIF-1alpha mRNA and protein (tunica intima). CONCLUSION: MAPK as a signal transduction may play an important role in the development of hypoxia-induced pulmonary hypertension.