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1.
Cell Discov ; 10(1): 14, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38320990

ABSTRACT

The current SARS-CoV-2 variants strikingly evade all authorized monoclonal antibodies and threaten the efficacy of serum-neutralizing activity elicited by vaccination or prior infection, urging the need to develop antivirals against SARS-CoV-2 and related sarbecoviruses. Here, we identified both potent and broadly neutralizing antibodies from a five-dose vaccinated donor who exhibited cross-reactive serum-neutralizing activity against diverse coronaviruses. Through single B-cell sorting and sequencing followed by a tailor-made computational pipeline, we successfully selected 86 antibodies with potential cross-neutralizing ability from 684 antibody sequences. Among them, PW5-570 potently neutralized all SARS-CoV-2 variants that arose prior to Omicron BA.5, and the other three could broadly neutralize all current SARS-CoV-2 variants of concern, SARS-CoV and their related sarbecoviruses (Pangolin-GD, RaTG13, WIV-1, and SHC014). Cryo-EM analysis demonstrates that these antibodies have diverse neutralization mechanisms, such as disassembling spike trimers, or binding to RBM or SD1 to affect ACE2 binding. In addition, prophylactic administration of these antibodies significantly protects nasal turbinate and lung infections against BA.1, XBB.1, and SARS-CoV viral challenge in golden Syrian hamsters, respectively. Importantly, post-exposure treatment with PW5-5 and PW5-535 also markedly protects against XBB.1 challenge in these models. This study reveals the potential utility of computational process to assist screening cross-reactive antibodies, as well as the potency of vaccine-induced broadly neutralizing antibodies against current SARS-CoV-2 variants and related sarbecoviruses, offering promising avenues for the development of broad therapeutic antibody drugs.

2.
Nutr Metab (Lond) ; 19(1): 84, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36578045

ABSTRACT

BACKGROUND: Evidence from previous studies has suggested that ginger extract exhibits the potential as an alternative treatment for Coronavirus disease 2019 (COVID-19). Here, we want to investigate whether ginger supplement improves the clinical manifestation of hospitalized COVID-19 individuals. METHODS: A total of 227 hospitalized individuals with COVID-19 were randomized to either the control (n = 132) or intervention group (n = 95). The intervention group took ginger supplement orally at the dosage of 1.5 g twice daily, until they were discharged from the hospital. Both groups received the same standard of general medical care during hospitalization, and the length of stay was recorded and compared between groups. RESULTS: Among all participants, a significant reduction in hospitalization time (the difference between the treatment and control groups was 2.4 d, 95% CI 1.6-3.2) was detected in response to the ginger supplement. This effect was more pronounced in men, participants aged 60 years or older, and participants with pre-existing medical conditions, relative to their counterparts (P-interactions < 0.05 for all). CONCLUSION: Ginger supplement significantly shortened the length of stay of hospitalized individuals with COVID-19. TRIAL REGISTRATION: The trial was registered on the Chinese Clinical Trial Registry (ChiCTR2200059824).

3.
Front Pharmacol ; 12: 632569, 2021.
Article in English | MEDLINE | ID: mdl-33692694

ABSTRACT

The effects of ginger on gastrointestinal disorders such as ulcerative colitis have been widely investigated using experimental models; however, the mechanisms underlying its therapeutic actions are still unknown. In this study, we investigated the correlation between the therapeutic effects of ginger and the regulation of the gut microbiota. We used dextran sulfate sodium (DSS) to induce colitis and found that ginger alleviated colitis-associated pathological changes and decreased the mRNA expression levels of interleukin-6 and inducible nitric oxide synthase in mice. 16s rRNA sequencing analysis of the feces samples showed that mice with colitis had an intestinal flora imbalance with lower species diversity and richness. At the phylum level, a higher abundance of pathogenic bacteria, Proteobacteria and firmicutes, were observed; at the genus level, most samples in the model group showed an increase in Lachnospiraceae_NK4A136_group. The overall analysis illustrated an increase in the relative abundance of Lactobacillus_murinus, Lachnospiraceae_bacterium_615, and Ruminiclostridium_sp._KB18. These increased pathogenic bacteria in model mice were decreased when treated with ginger. DSS-treated mice showed a lower abundance of Muribaculaceae, and ginger corrected this disorder. The bacterial community structure of the ginger group analyzed with Alpha and Beta indices was similar to that of the control group. The results also illustrated that altered intestinal microbiomes affected physiological functions and adjusted key metabolic pathways in mice. In conclusion, this research presented that ginger reduced DSS-induced colitis severity and positively regulated the intestinal microbiome. Based on the series of data in this study, we hypothesize that ginger can improve diseases by restoring the diversity and functions of the gut microbiota.

4.
JMIR Med Inform ; 8(12): e23082, 2020 Dec 21.
Article in English | MEDLINE | ID: mdl-33346740

ABSTRACT

BACKGROUND: Integrative medicine is a form of medicine that combines practices and treatments from alternative medicine with conventional medicine. The diagnosis in integrative medicine involves the clinical diagnosis based on modern medicine and syndrome pattern diagnosis. Electronic medical records (EMRs) are the systematized collection of patients health information stored in a digital format that can be shared across different health care settings. Although syndrome and sign information or relative information can be extracted from the EMR and content texts can be mapped to computability vectors using natural language processing techniques, application of artificial intelligence techniques to support physicians in medical practices remains a major challenge. OBJECTIVE: The purpose of this study was to investigate model-based reasoning (MBR) algorithms for the clinical diagnosis in integrative medicine based on EMRs and natural language processing. We also estimated the associations among the factors of sample size, number of syndrome pattern type, and diagnosis in modern medicine using the MBR algorithms. METHODS: A total of 14,075 medical records of clinical cases were extracted from the EMRs as the development data set, and an external test data set consisting of 1000 medical records of clinical cases was extracted from independent EMRs. MBR methods based on word embedding, machine learning, and deep learning algorithms were developed for the automatic diagnosis of syndrome pattern in integrative medicine. MBR algorithms combining rule-based reasoning (RBR) were also developed. A standard evaluation metrics consisting of accuracy, precision, recall, and F1 score was used for the performance estimation of the methods. The association analyses were conducted on the sample size, number of syndrome pattern type, and diagnosis of lung diseases with the best algorithms. RESULTS: The Word2Vec convolutional neural network (CNN) MBR algorithms showed high performance (accuracy of 0.9586 in the test data set) in the syndrome pattern diagnosis of lung diseases. The Word2Vec CNN MBR combined with RBR also showed high performance (accuracy of 0.9229 in the test data set). The diagnosis of lung diseases could enhance the performance of the Word2Vec CNN MBR algorithms. Each group sample size and syndrome pattern type affected the performance of these algorithms. CONCLUSIONS: The MBR methods based on Word2Vec and CNN showed high performance in the syndrome pattern diagnosis of lung diseases in integrative medicine. The parameters of each group's sample size, syndrome pattern type, and diagnosis of lung diseases were associated with the performance of the methods. TRIAL REGISTRATION: ClinicalTrials.gov NCT03274908; https://clinicaltrials.gov/ct2/show/NCT03274908.

5.
J Pharm Biomed Anal ; 175: 112769, 2019 Oct 25.
Article in English | MEDLINE | ID: mdl-31398628

ABSTRACT

A sensitive detection electrode based on the composite of carbon nanotubes (CNTs) and polylactic acid (PLA) was fabricated for measuring the bioactive constituents in Belamcandae Rhizoma by capillary electrophoresis (CE). The composite was facilely fabricated by packing a blend of CNTs and melted PLA into a fused silica capillary under heat. The prepared CNT-PLA composite was characterized by scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and cyclic voltammetry. The results indicated that PLA bound electrically conductive CNTs to form a well-dispersed composite network for electrochemical sensing. The electrode was employed to the off-line detection of tectoridin and irigenin in Belamcandae Rhizoma to demonstrate its performance in capillary electrophoresis. At a separation voltage of 12 kV, the two isoflavones were well separated and detected within 8 min in a 40-cm fused silica capillary in a borate buffer at pH 9.8. The detection limits for tectoridin and irigenin were measured to be 0.24 and 0.21 µM, respectively.


Subject(s)
Drugs, Chinese Herbal/chemistry , Isoflavones/chemistry , Nanotubes, Carbon/chemistry , Polyesters/chemistry , Rhizome/chemistry , Electrodes , Electrophoresis, Capillary/methods , Limit of Detection , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods
6.
J Integr Med ; 16(6): 418-426, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30341024

ABSTRACT

OBJECTIVE: Acupuncture has a definite therapeutic effect on chronic obstructive pulmonary disease (COPD), and the cholinergic anti-inflammatory pathway (CAP) has been shown to be involved in regulation of inflammation. In this study, we investigated whether electro-acupuncture (EA) affects the CAP in COPD. METHODS: Sprague-Dawley rats were induced into COPD through exposure to cigarette smoke combined with lipopolysaccharide. EA treatment was applied at Zusanli (ST36) and Feishu (BL13) points for 30 min/d for 7 d. Seventy-two rats were randomly divided into six study groups, including normal, normal + EA, normal + α-bungarotoxin (α-BGT) (the antagonist of the nicotinic acetylcholine receptor α7 subunit (α7nAChR)) + EA, COPD, COPD + EA, and COPD + α-BGT + EA. Lung function, pathology and vagus nerve discharge were tested. The levels of acetylcholine (ACh), acetylcholinesterase (AChE), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in bronchoalveolar lavage fluid (BALF) and lung tissue were measured by enzyme-linked immunosorbent assay. The mRNA and protein expression and immunoreactivity of α7nAChR and its postreceptor inflammation signal pathway, including janus kinase 2 (JAK2), signal transducers and activators of transcription 3 (STAT3), nuclear factor-κB (NF-κB), were observed by quantitative reverse transcription-polymerase chain reaction, Western blot and immunohistochemistry. RESULTS: Compared with normal rats, there were a significant decline in lung function and discharge of the vagus nerve (P < 0.01), a marked sign of lung inflammation and an increase of ACh, AChE, IL-6 and TNF-α level in BALF or lung tissue (P < 0.05, P < 0.01) and higher expression of α7nAChR, JAK2, STAT3 and NF-κB (P < 0.05, P < 0.01) in the COPD rats. In rats receiving EA, the lung function and vagal discharge were enhanced (P < 0.01), lung inflammation was improved and the levels of ACh, AChE, IL-6 and TNF-α were decreased (P < 0.01). Further, the expression of α7nAChR, JAK2, STAT3 and NF-κB was downregulated (P < 0.05, P < 0.01). However, the above effects of EA were blocked in rats injected with α-BGT (P < 0.01). CONCLUSION: EA treatment can reduce the lung inflammatory response and improve lung function in COPD, which may be related to its involvement in the regulation of CAP.


Subject(s)
Acetylcholine/immunology , Electroacupuncture , Pulmonary Disease, Chronic Obstructive/immunology , Pulmonary Disease, Chronic Obstructive/therapy , Animals , Disease Models, Animal , Humans , Interleukin-6/genetics , Interleukin-6/immunology , Lung/immunology , Male , NF-kappa B/genetics , NF-kappa B/immunology , Pulmonary Disease, Chronic Obstructive/genetics , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology
7.
Acupunct Med ; 36(5): 312-318, 2018 10.
Article in English | MEDLINE | ID: mdl-29669795

ABSTRACT

OBJECTIVES: Decreased lung function in chronic obstructive pulmonary disease (COPD) is correlated with abnormal excitability of the respiratory centre where orexin neuropeptides from the hypothalamus are responsible for regulating respiration. We hypothesised that improvements in pulmonary function with electroacupuncture (EA) may be related to orexins in a rat model of COPD. METHODS: The COPD model was established by cigarette smoke exposure and lipopolysaccharide injection. Modelled rats received EA at BL13 and ST36 for two weeks, after which lung function was tested. Orexin levels in the hypothalamus and medulla were detected by ELISA, while mRNA/protein expression and localisation of orexins and their receptors were investigated using real time PCR, Western blotting and immunohistochemistry, respectively. RESULTS: The decrease in lung function observed in COPD rats was improved after EA treatment. Orexin levels in the hypothalamus and medulla were significantly higher in COPD rats than in normal rats, but were significantly reduced in the EA-treated group. There was a negative correlation between orexin content and lung function. In the hypothalamus, mRNA and protein expression and immunoreactivity of orexins were significantly higher in the COPD group than in the normal group, but a significant decrease was observed after EA. In the medulla, the expression and immunoreactivity of orexin receptors were significantly higher in the COPD group than in the normal group, but a significant decrease was observed after EA. CONCLUSIONS: The positive effect of EA on pulmonary function in COPD rats may be related to downregulation of orexins and their receptors in the medulla.


Subject(s)
Electroacupuncture , Hypothalamus/metabolism , Medulla Oblongata/metabolism , Orexins/genetics , Pulmonary Disease, Chronic Obstructive/therapy , Acupuncture Points , Animals , Disease Models, Animal , Humans , Lung/metabolism , Male , Orexin Receptors/genetics , Orexin Receptors/metabolism , Orexins/metabolism , Pulmonary Disease, Chronic Obstructive/genetics , Pulmonary Disease, Chronic Obstructive/metabolism , Rats , Rats, Sprague-Dawley
8.
Exp Biol Med (Maywood) ; 242(15): 1534-1541, 2017 09.
Article in English | MEDLINE | ID: mdl-28795606

ABSTRACT

Chronic obstructive pulmonary disease induced by tobacco smoke has been regarded as a great health problem worldwide. The purpose of this study is to evaluate the protective effect of hydrogen-rich saline, a novel antioxidant, on chronic obstructive pulmonary disease and explore the underlying mechanism. Sprague-Dawley rats were made chronic obstructive pulmonary disease models via tobacco smoke exposure for 12 weeks and the rats were treated with 10 ml/kg hydrogen-rich saline intraperitoneally during the last 4 weeks. Lung function testing indicated hydrogen-rich saline decreased lung airway resistance and increased lung compliance and the ratio of forced expiratory volume in 0.1 s/forced vital capacity in chronic obstructive pulmonary disease rats. Histological analysis revealed that hydrogen-rich saline alleviated morphological impairments of lung in tobacco smoke-induced chronic obstructive pulmonary disease rats. ELISA assay showed hydrogen-rich saline lowered the levels of pro-inflammatory cytokines (IL-8 and IL-6) and anti-inflammatory cytokine IL-10 in bronchoalveolar lavage fluid and serum of chronic obstructive pulmonary disease rats. The content of malondialdehyde in lung tissue and serum was also determined and the data indicated hydrogen-rich saline suppressed oxidative stress reaction. The protein expressions of mucin MUC5C and aquaporin 5 involved in mucus hypersecretion were analyzed by Western blot and ELISA and the data revealed that hydrogen-rich saline down-regulated MUC5AC level in bronchoalveolar lavage fluid and lung tissue and up-regulated aquaporin 5 level in lung tissue of chronic obstructive pulmonary disease rats. In conclusion, these results suggest that administration of hydrogen-rich saline exhibits significant protective effect on chronic obstructive pulmonary disease through alleviating inflammation, reducing oxidative stress and lessening mucus hypersecretion in tobacco smoke-induced chronic obstructive pulmonary disease rats. Impact statement This study was designed to evaluate protective effect of hydrogen-rich saline, a novel antioxidant, on tobacco smoke (TS)-induced chronic obstructive pulmonary disease (COPD) in rats and explore the underlying mechanism. Our results suggest that administration of hydrogen-rich saline improves lung function and alleviates morphological impairments of lung through alleviating inflammation, reducing oxidative stress and lessening mucus hypersecretion in TS-induced COPD rats.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Hydrogen/administration & dosage , Mucin 5AC/analysis , Mucus/metabolism , Pulmonary Disease, Chronic Obstructive/prevention & control , Smoke/adverse effects , Sodium Chloride/administration & dosage , Animals , Blotting, Western , Bronchoalveolar Lavage Fluid/chemistry , Cytokines/analysis , Disease Models, Animal , Enzyme-Linked Immunosorbent Assay , Histocytochemistry , Injections, Intraperitoneal , Male , Pulmonary Disease, Chronic Obstructive/pathology , Pulmonary Disease, Chronic Obstructive/physiopathology , Rats, Sprague-Dawley , Respiratory Function Tests , Treatment Outcome
9.
J Integr Med ; 12(5): 417-24, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25292341

ABSTRACT

OBJECTIVE: Inflammation and lung function decline are the main pathophysiological features of chronic obstructive pulmonary disease (COPD). Acupuncture can improve lung function in patients with COPD, but the underlying mechanisms are not well understood. Orexins (OXs), which are found in peripheral plasma, are neuropeptides that regulate respiration and their levels are related to COPD. Therefore, we hypothesized that acupuncture might alter OXs, reduce lung inflammation and improve lung function in COPD. METHODS: COPD was induced in rats by exposure to cigarette smoke for 8 weeks and injecting with lipopolysaccharide twice. Electroacupuncture (EA) was performed at Feishu (BL13) and Zusanli (ST36) for 30 min/d for 2 weeks. Rat lung function and morphology were assessed after EA. The levels of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) in bronchoalveolar lavage fluid (BALF) and orexin A and B levels in the lung tissue were detected by enzyme-linked immunosorbent assay. OX receptor mRNA levels and immunopositive cells were assessed with real-time polymerase chain reaction and immunohistochemical methods, respectively. The relationships among lung function, cell factors, and OX levels were analyzed by Pearson correlation analyses. RESULTS: Compared with the control group, lung function was significantly decreased in the rats with COPD (P<0.05). There were increases in TNF-α and IL-1ß levels in BALF (P<0.05 and P<0.01, respectively), orexin A level in lung tissue (P<0.01; but not orexin B) and mRNA expressions of OX (OXR1) and OX 2 (OXR2) in lung tissue (P<0.05 and P<0.01, respectively); the integrative optical densities (IODs) of both receptors were greater in the COPD group (P<0.05). For rats with COPD subjected to EA, lung function was improved (P<0.05). There were notable decreases in TNF-α and IL-1ß levels (P<0.05 and <0.01, respectively) in BALF. Orexin A, but not orexinB, levels in lung tissue also decreased (P<0.01), as did mRNA expression of OX1R and OX2R in lung tissue (P<0.05 and P<0.01, respectively). Receptor IODs were also reduced after EA treatment (P<0.05). Furthermore, orexin A levels and ratio of forced expiratory volume in 0.3 s to forced vital capacity were strongly negatively correlated (P<0.01), and orexin A was positively correlated with TNF-α and IL-1ß (P<0.001 and P<0.05, respectively). CONCLUSION: EA at Zusanli and Feishu improved lung function of rats with COPD and had an anti-inflammatory effect, which may be related to down-regulation of OXA and its receptors.


Subject(s)
Electroacupuncture , Intracellular Signaling Peptides and Proteins/analysis , Neuropeptides/analysis , Orexin Receptors/analysis , Pulmonary Disease, Chronic Obstructive/therapy , Animals , Down-Regulation , Interleukin-1beta/analysis , Intracellular Signaling Peptides and Proteins/genetics , Lung/physiopathology , Male , Neuropeptides/genetics , Orexin Receptors/genetics , Orexins , Pulmonary Disease, Chronic Obstructive/physiopathology , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/analysis
10.
J Integr Med ; 11(3): 213-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23743164

ABSTRACT

OBJECTIVE: Improvement in lung function was reported after acupuncture treatment of chronic obstructive pulmonary disease (COPD), but little is known about the underlying mechanisms. Because an immune response imbalance could be seen in COPD, we hypothesize that electroacupuncture (EA) may play a role in regulating inflammatory cytokines and contribute to lung protection in a rat model of smoke-induced COPD. METHODS: A COPD model using male Sprague-Dawley rats exposed to cigarette smoke was established. The rats were randomly divided into four groups (control, sham, COPD, and COPD plus EA), and COPD model was evaluated by measuring pulmonary pathological changes and lung function. EA was applied to the acupuncture point Zusanli (ST36) for 30 min/d for 14 d in sham and COPD rats. Bronchoalveolar lavage fluid (BALF) was used to measure levels of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and malonaldehyde (MDA). RESULTS: Compared with the control rats, COPD rats had significant changes in lung resistance (RL) and lung compliance (CL) (both P<0.01), bronchi and bronchiole airway obstruction (P<0.01), and levels of MDA, TNF-α, and IL-1ß (P<0.01). There were no significant differences between the control and the sham groups. Compared with the COPD rats, the COPD plus EA rats had decreased RL and increased CL (both P<0.05), and reduced bronchi and bronchiole airway obstruction (P<0.05, P<0.01, respectively), while levels of TNF-α, IL-1ß, and MDA in BALF were lowered (P<0.05 and P<0.01, respectively). However, TNF-α and IL-1ß levels of the EA group rats remained higher than those of the control group (P<0.05). CONCLUSION: EA at ST36 can reduce lung injury in a COPD rat model, and beneficial effects may be related to down-regulation of inflammatory cytokines. The anti-inflammatory and antioxidant effects may prolong the clinical benefit of EA.


Subject(s)
Acupuncture Points , Electroacupuncture , Interleukin-1beta/immunology , Pulmonary Disease, Chronic Obstructive/immunology , Pulmonary Disease, Chronic Obstructive/therapy , Smoking/adverse effects , Tumor Necrosis Factor-alpha/immunology , Animals , Bronchoalveolar Lavage Fluid/immunology , Disease Models, Animal , Humans , Male , Pulmonary Disease, Chronic Obstructive/etiology , Rats , Rats, Sprague-Dawley
11.
PLoS One ; 7(7): e39982, 2012.
Article in English | MEDLINE | ID: mdl-22792205

ABSTRACT

Acid-sensing ion channels (ASICs) are present in neurons and may contribute to chemoreception. Among six subunits of ASICs, ASIC1 is mainly expressed in the central nervous system. Recently, multiple sites in the brain including the lateral hypothalamus (LH) have been found to be sensitive to extracellular acidification. Since LH contains orexin neurons and innervates the medulla respiratory center, we hypothesize that ASIC1 is expressed on the orexin neuron and contributes to acid-induced increase in respiratory drive. To test this hypothesis, we used double immunofluorescence to determine whether ASIC1 is expressed on orexin neurons in the LH, and assessed integrated phrenic nerve discharge (iPND) in intact rats in response to acidification of the LH. We found that ASIC1 was co-localized with orexinA in the LH. Microinjection of acidified artificial cerebrospinal fluid increased the amplitude of iPND by 70% (pH 7.4 v.s. pH 6.5:1.05±0.12 v.s. 1.70±0.10, n = 6, P<0.001) and increased the respiratory drive (peak amplitude of iPND/inspiratory time, PA/Ti) by 40% (1.10±0.23 v.s. 1.50±0.38, P<0.05). This stimulatory effect was abolished by blocking ASIC1 with a nonselective inhibitor (amiloride 10 mM), a selective inhibitor (PcTX1, 10 nM) or by damaging orexin neurons in the LH. Current results support our hypothesis that the orexin neuron in the LH can exert an excitation on respiration via ASIC1 during local acidosis. Since central acidification is involved in breathing dysfunction in a variety of pulmonary diseases, understanding its underlying mechanism may improve patient management.


Subject(s)
Acid Sensing Ion Channels/metabolism , Hypothalamus/metabolism , Respiration , Acid Sensing Ion Channel Blockers/pharmacology , Acid Sensing Ion Channels/genetics , Acidosis , Amiloride/pharmacology , Animals , Arterial Pressure/drug effects , Body Weight/drug effects , Gene Expression , Heart Rate/drug effects , Hydrogen-Ion Concentration , Hypothalamus/drug effects , Intracellular Signaling Peptides and Proteins/metabolism , Male , Neurons/drug effects , Neurons/metabolism , Neuropeptides/metabolism , Orexins , Phrenic Nerve/drug effects , Phrenic Nerve/physiology , Rats , Rats, Sprague-Dawley , Respiration/drug effects , Respiration/genetics , Respiratory Center/drug effects , Respiratory Center/metabolism , Respiratory Rate/drug effects
12.
Clin Exp Pharmacol Physiol ; 37(10): 963-8, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20528981

ABSTRACT

1. Orexins are neuropeptides synthesized in the hypothalamus that regulate many physiological functions, including energy homeostasis, stress responses, sleep/wake states etc. It is now emerging that orexins may also regulate breathing, but little is known as to how they do this, particularly in chronic obstructive pulmonary disease (COPD). In the present study, we used a rat model of cigarette smoke-induced COPD to investigate orexin-A expression in the hypothalamus and medulla and its effect on respiration. 2. Sprague-Dawley rats were exposed to cigarette smoke (1 h twice daily) for 12 weeks. Lung function and pathological changes associated with inflammation and emphysema were determined to confirm the validity of the COPD model. 3. Hypothalamic and medullary orexin-A levels, as determined by radioimmunoassay, were higher in smoke-exposed than control rats. Furthermore, the expression of prepro-orexin (PPO) mRNA in the hypothalamus and orexin OX(1) receptor mRNA in the medulla, as determined by real-time quantitative polymerase chain reaction, was higher in smoke-exposed than control rats. 4. The number of orexin-A-positive neurons in the hypothalamus and OX(1) and OX(2) receptor-positive neurons in the ventrolateral medulla was higher in smoke-exposed than control rats. 5. Microinjection of orexin-A (1 µmol/L, 0.1 µL) into the pre-Bötzinger complex enhanced phrenic nerve discharge to a greater extent in smoke-exposed compared with control rats (61% vs 36%, respectively). 6. The findings of the present study demonstrate that the increased respiratory activity in smoke-exposed rats is due to an increase in orexin-A as well as upregulation of orexin receptors in the ventrolateral medulla.


Subject(s)
Disease Models, Animal , Neuropeptides/biosynthesis , Pulmonary Disease, Chronic Obstructive/metabolism , Respiratory Mechanics/physiology , Smoking/metabolism , Animals , Hypothalamus/metabolism , Hypothalamus/physiopathology , Intracellular Signaling Peptides and Proteins , Lung/metabolism , Lung/pathology , Lung/physiopathology , Male , Medulla Oblongata/metabolism , Medulla Oblongata/physiopathology , Orexins , Protein Precursors/biosynthesis , Pulmonary Disease, Chronic Obstructive/etiology , Pulmonary Disease, Chronic Obstructive/physiopathology , Rats , Rats, Sprague-Dawley , Smoking/adverse effects
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