Protective effect of electro-acupuncture at maternal different points on perinatal nicotine exposure-induced pulmonary dysplasia in offspring based on HPA axis and signal transduction pathway

Effects of acupuncture on hypothalamic-pituitary-adrenal axis: Current status and future perspectives

The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the neuroendocrine system, playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus, hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA axis. This review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture. Please cite this article as: Zheng JY, Zhu J, Wang Y, Tian ZZ. Effects of acupuncture on hypothalamic-pituitary-adrenal axis: Current status and future perspectives. J Integr Med. 2024; 22(4): 446-459.

Research on the Mechanism and Application of Acupuncture Therapy for Asthma: A Review

Asthma is a high-risk disease based on airway hyperresponsiveness (AHR). In this review, we found that there are many studies on clinical therapy for asthma that focus on the efficacy of acupuncture therapy and its mechanisms, including the functional connectivity of different brain regions, with the aid of functional magnetic resonance imaging (fMRI), immune responses/cell recognition (innate lymphoid cells and balance of Th1/Th2 and Treg/Th17), intracellular mechanism (autophagy, endoplasmic reticulum stress, and epigenetic alteration), and ligand-receptor/chemical signaling pathway (neurotransmitter, hormone, and small molecules). In this review, we summarized the clinical and experimental evidence for the mechanisms of acupuncture therapy in asthma to offer insights into drug discovery and clinical therapy. Given the paucity of clinical studies on the mechanisms of acupuncture in the treatment of asthma, this review notably included studies based on animal models to investigate the mechanisms of acupuncture in the treatment of asthma.

Revealing the clinical effect and biological mechanism of acupuncture in COPD: A review

BACKGROUND

To provide new ideas for the clinical and mechanism research of acupuncture in the treatment of chronic obstructive pulmonary disease (COPD), this study systematically reviews clinical research and the progress of basic research of acupuncture in the treatment of COPD.

METHODS

PubMed and Web of Science databases were searched using acupuncture and COPD as keywords in the last 10 years, and the included literature was determined according to exclusion criteria.

FINDINGS

Acupuncture can relieve clinical symptoms, improve exercise tolerance, anxiety, and nutritional status, as well as hemorheological changes (blood viscosity), reduce the inflammatory response, and reduce the duration and frequency of COPD in patients with COPD. Mechanistically, acupuncture inhibits M1 macrophage activity, reduces neutrophil infiltration, reduces inflammatory factor production in alveolar type II epithelial cells, inhibits mucus hypersecretion of airway epithelial cells, inhibits the development of chronic inflammation in COPD, and slows tissue structure destruction. Acupuncture may control pulmonary COPD inflammation through the vagal-cholinergic anti-inflammatory, vagal-adrenomedullary-dopamine, vagal-dual-sensory nerve fiber-pulmonary, and CNS-hypothalamus-orexin pathways. Furthermore, acupuncture can increase endogenous cortisol levels by inhibiting the HPA axis, thus improving airway antioxidant capacity and reducing airway inflammation in COPD. In conclusion, the inhibition of the chronic inflammatory response is the key mechanism of acupuncture treatment for COPD.

Evidence for Wnt signaling's central involvement in perinatal nicotine exposure-induced offspring lung pathology and its modulation by electroacupuncture

OBJECTIVE

Many factors during pregnancy can induce intrauterine growth restriction (IUGR), resulting in various adverse perinatal outcomes such as low birth weight and multiple organ disorders. Among these factors, prenatal smoke/nicotine exposure is a common cause of IUGR, often associated with altered fetal lung development. The classical Wnt signaling pathway plays a vital role in lung development, and its alterations are commonly associated with developmental lung pathologies. The purpose of this study was to determine whether electroacupuncture (EA) at "Zusanli" (ST 36) points protects perinatal nicotine exposure (PNE)-induced offspring lung dysplasia through Wnt/β-catenin signaling pathway and to identify specific Wnt signaling pathway targets of EA.

METHODS

Following a well-established protocol, nicotine (1 mg/kg/ body weight) was administered subcutaneously to pregnant Sprague Dawley rat dams from gestational day 6 to postnatal day 21. In the EA group, dams were treated with EA at both ST 36 acupoints, while in another experimental group, Wnt/β-catenin signaling pathway agonist was injected subcutaneously (2 mg/kg/ body weight). Offspring body weight (PND 1, 7, 14, and 21), lung weight, Wnt signaling markers, pulmonary function, and lung morphology were determined at sacrifice on PND 21. Specifically, Western blotting and Real-time PCR were used to detect the protein and mRNA levels of critical Wnt signaling markers Wnt2, Wnt7b, FZD4, FZD7, LRP5, and LRP6 in the offspring lung. The protein levels of β-catenin in lung tissue of offspring rats were detected by ELISA that of LEF-1 by Western blotting.

RESULTS

Compared to the control group, the body and lung weights of the offspring rats were significantly decreased in the nicotine-only exposed group. The pulmonary function determined as FVC, PEF, TV, and Cdyn was also significantly decreased, while PIF was significantly increased. The protein levels and mRNA expression of Wnt2, Wnt7b, FZD4, FZD7, LRP5, and LRP6 in the lung tissue of the PNE offspring rats were significantly increased. With EA administration at ST 36 acupoints concomitant with nicotine administration, the body and lung weights, pulmonary function (FVC, PEF, PIF, TV, and Cdyn), protein and mRNA levels Wnt signaling pathway markers (Wnt2, Wnt7b, FZD4, FZD7, LRP5, LRP6, β-catenin, and LEF-1) normalized and were not different from the control group. Notably, Wnt agonists agonist administration blocked the protective effects of EA against PNE-induced lung morphological, molecular, and function changes, highlighting the central significance of Wnt pathway signaling in PNE-induced offspring pulmonary pathology and its modulation by EA at ST 36 acupoints.

CONCLUSION

Concomitant maternal EA at ST 36 acupoints from gestational day 6 to PND 21 protects against offspring PNE-induced lung phenotype. The protective effect is achieved by regulating the expression of Wnt ligand proteins (Wnt2 and Wnt7b) and receptor proteins (FZD4, FZD7, LRP5, and LRP6) upstream of the Wnt/β-catenin signaling pathway intermediates β-catenin, and LEF-1.

The Potential Role of PPARs in the Fetal Origins of Adult Disease

The fetal origins of adult disease (FOAD) hypothesis holds that events during early development have a profound impact on one’s risk for the development of future adult disease. Studies from humans and animals have demonstrated that many diseases can begin in childhood and are caused by a variety of early life traumas, including maternal malnutrition, maternal disease conditions, lifestyle changes, exposure to toxins/chemicals, improper medication during pregnancy, and so on. Recently, the roles of Peroxisome proliferator-activated receptors (PPARs) in FOAD have been increasingly appreciated due to their wide variety of biological actions. PPARs are members of the nuclear hormone receptor subfamily, consisting of three distinct subtypes: PPARα, β/δ, and γ, highly expressed in the reproductive tissues. By controlling the maturation of the oocyte, ovulation, implantation of the embryo, development of the placenta, and male fertility, the PPARs play a crucial role in the transition from embryo to fetus in developing mammals. Exposure to adverse events in early life exerts a profound influence on the methylation pattern of PPARs in offspring organs, which can affect development and health throughout the life course, and even across generations. In this review, we summarize the latest research on PPARs in the area of FOAD, highlight the important role of PPARs in FOAD, and provide a potential strategy for early prevention of FOAD.

Electroacupuncture at Zusanli ameliorates the autistic-like behaviors of rats through activating the Nrf2-mediated antioxidant responses

OBJECTIVE

Emerging evidence suggests that acupuncture plays a neuroprotective role in autism. This study aimed to explore the effect of electroacupuncture at Zusanli (ST36) on autistic-like behaviors and the underlying mechanism.

METHOD

Pregnant rats were administered with valproic acid (VPA) on gestational day 12.5 to induce an autism spectrum disorder (ASD) model. The pups were given electroacupuncture at ST36 daily from postnatal day (PND) 28-48. On PND28, the adenoviral vector containing small interfering RNA Nrf2 (Ad-siRNA-Nrf2) was injected into the prefrontal cortex of rats. The behavioral analysis was performed on PND 44-48. On PND48, the animals were euthanized and the brains were collected for further detection. Nissl staining was performed to detect neuronal viability. The biochemical markers of oxidative stress were subsequently measured.

RESULT

Electroacupuncture at ST36 ameliorated the locomotor activity, social behavior, spatial learning and memory and repetitive behavior compared with ASD rats. It was notable that the electroacupuncture decreased oxidative stress markers in the tissues of prefrontal cortex, enhanced translocation of nuclear factor erythroid2-related factor2 (Nrf2) from cytoplasm to nucleus, and up-regulated the levels of NADP(H) quinone oxidoreductase (NQO1) and heme oxygenase (HO-1). However, these effects induced by electroacupuncture at ST36 were abolished after injection of Ad-siRNA-Nrf2.

CONCLUSION

These data suggested that electroacupuncture at ST36 protected nerve function in ASD rats through Nrf2 activation and the antioxidant response.

Acupuncture at ST36 Alleviates the Behavioral Disorder of Autistic Rats by Inhibiting TXNIP-Mediated Activation of NLRP3

Autism is a common neurodevelopmental disorder that severely affects patients' quality of life. We aimed to investigate whether acupuncture at Zusanli (ST36) could alleviate the behavior disorder of autistic rats by inhibiting thioredoxin-interacting protein (TXNIP)-mediated activation of NLRP3. An autism model was induced by intraperitoneal injection of pregnant rats with valproic acid (VPA). The pups' behaviors were analyzed using hot plate, open field, Morris water maze, and 3-chamber social interaction tests. Nissl staining was used to visualize neurons in prefrontal cortex. Levels of TXNIP, NLRP3, interleukin (IL)-1β, and caspase were determined by Western blot or quantitative real-time PCR. After ST36 acupuncture, pain sensitivity, autonomous activity, sociability index, sociability preference index, and learning and memory were improved in the autism model rats. Levels of TXNIP, NLRP3, IL-1β, and caspase 1 were decreased after acupuncture. Interference with TXNIP alleviated the behavior disorders and inhibited NLRP3, caspase 1, and IL-1β levels. In summary, ST36 acupuncture reduced TXNIP expression, inhibited the activation of the NLRP3 inflammasome, and alleviated the behavior disorder related to the prefrontal cortex of the autistic rats. These results point to a potential mechanism for acupuncture-induced improvement of autistic behavioral disorders.

GluN2A/ERK/CREB Signaling Pathway Involved in Electroacupuncture Regulating Hypothalamic-Pituitary-Adrenal Axis Hyperactivity

The hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis caused by stress will inevitably disrupt the homeostasis of the neuroendocrine system and damage physiological functions. It has been demonstrated that electroacupuncture (EA) can modulate HPA axis hyperactivity during the perioperative period. As the initiating factor of the HPA axis, hypothalamic corticotrophin-releasing hormone (CRH) is the critical molecule affected by EA. However, the mechanism by which EA reduces CRH synthesis and secretion remains unclear. Activated N-methyl-D-aspartate receptor (NMDAR) has been linked to over-secretion of hypothalamic CRH induced by stress. To determine whether NMDAR is involved in EA regulating the over-expression of CRH, a surgical model of partial hepatectomy (HT) was established in our experiment. The effect of EA on hypothalamic NMDAR expression in HT mice was examined. Then, we investigated whether the extracellular regulated protein kinases (ERK)/cyclic adenosine monophosphate response element-binding protein (CREB) signaling pathway mediated by NMDAR was involved in EA regulating HPA axis hyperactivity. It was found that surgery enhanced the expression of hypothalamic CRH and caused HPA axis hyperactivity. Intriguingly, EA effectively suppressed the expression of CRH and decreased the activation of GluN2A (NMDAR subunit), ERK, and CREB in HT mice. GluN2A, ERK, and CREB antagonists had similar effects on normalizing the expression of CRH and HPA axis function compared with EA. Our findings suggested that surgery enhanced the activation of the hypothalamic GluN2A/ERK/CREB signaling pathway, thus promoting the synthesis and secretion of CRH. EA suppressed the phosphorylation of GluN2A, ERK, and CREB in mice that had undergone surgery, indicating that the GluN2A/ERK/CREB signaling pathway was involved in EA alleviating HPA axis hyperactivity.

Electroacupuncture inhibits the corneal ROS/TXNIP/NLRP3 signaling pathway in a rat model of dry eye syndrome

BACKGROUND

Electroacupuncture (EA) treatment has been found to ameliorate clinical symptoms in patients with dry eye, but its mechanisms are still not entirely clear.

OBJECTIVE

To study the regulation of EA on ocular surface function and the corneal reactive oxygen species (ROS)/thioredoxin-interacting protein (TXNIP)/Nod-like receptor protein 3 (NLRP3) inflammatory signaling pathway in dry eye syndrome (DES) model rats.

METHODS

Male Sprague-Dawley (SD) rats were randomly divided into five groups: Normal, Model, Model + EA, Model + NAC (N-actetylcysteine) and Model + NS (normal saline). The DES model was developed by subcutaneous injection of scopolamine hydrobromide with exposure to an air draft in the latter four groups. After intervention, the Schirmer I test (SIT), tear film break-up time (BUT) and ROS content were measured, the histopathological changes of corneal tissues were observed, and the mRNA and protein expression levels of TXNIP, NLRP3, apoptosis-associated Speck-like protein containing CARD (ASC), caspase-1, interleukin (IL)-1β and IL-18 were detected.

RESULTS

Compared with the Model group, the SIT and BUT increased significantly in the Model + EA group after intervention (p < 0.05), and the corneal injury was improved. Corneal ROS content declined in both Model + EA and Model + NAC groups (p < 0.05), and mRNA expression of TXNIP, NLRP3, ASC and caspase-1 also decreased (p < 0.01). Corneal protein expression of TXNIP, NLRP3, IL-1β and IL-18 decreased significantly in the Model + EA group (p < 0.01).

CONCLUSION

Inhibiting the ROS/TXNIP/NLRP3 signaling pathway may be the mechanism underlying the role of EA in improving corneal injury in DES model rats.

Effect of electro-acupuncture at ST 36 on maternal food restriction-induced lung phenotype in rat offspring

Maternal food restriction (MFR) during pregnancy leads to pulmonary dysplasia in the newborn period and increases susceptibility to diseases, such as asthma and chronic lung disease, later in life. Previous studies have shown that maternal electro-acupuncture (EA) applied to "Zusanli" (ST 36) could prevent the abnormal expression of key lung developmental signaling pathways and improve the lung morphology and function in perinatal nicotine exposed offspring. There is a significant overlap in lung developmental signaling pathways affected by perinatal nicotine exposure and MFR during pregnancy; however, whether maternal EA at ST 36 also blocks the MFR-induced lung phenotype is unknown. Here, we examined the effects of EA applied to maternal ST 36 on lung morphology and function and the expression of key lung developmental signaling pathways, and the hypercorticoid state associated with MFR during pregnancy. These effects were compared with those of metyrapone, an intervention known to block MFR-induced offspring hypercorticoid state and the resultant pulmonary pathology. Like metyrapone, maternal EA at ST 36 blocked the MFR-induced changes in key developmental signaling pathways and protected the MFR-induced changes in lung morphology and function. These results offer a novel and safe, nonpharmacologic approach to prevent MFR-induced pulmonary dysplasia in offspring.

Contribution of Growth Arrest-Specific 5/miR-674 to the Hypothalamus Pituitary Adrenal Axis Regulation Effect by Electroacupuncture following Trauma

BACKGROUND

Electroacupuncture (EA) can improve trauma-induced hypothalamus pituitary adrenal axis (HPA) hyperactivity. However, the mechanism underlying the EA effect has not been fully understood.

METHODS AND STUDY DESIGN

This study was undertaken to explore the role of hypothalamic growth arrest-specific 5 (Gas5) in the regulation of EA on HPA axis function post-surgery. Paraventricular nuclear Gas5 levels were upregulated in rats using an intracerebroventricular injection of pAAV-Gas5. Primary hypothalamic neurons and 293T cells were cultured for miRNA and siRNAs detection. Radioimmunoassay, PCR, Western blot, and immunohistochemistry were used for HPA axis function evaluation.

RESULTS

The overexpression of Gas5 abolished the effect of EA on the regulation of trauma-induced HPA axis hyperactivity. Using a bioinformatics analysis and dual luciferase assay, we determined that miRNA-674 was a target of Gas5. Additionally, miRNA-674 levels were found to have decreased in trauma rats, and this effect was reversed after EA intervention. TargetScan analysis showed that serum and glucocorticoid inducible kinase 1 (SGK1) were targets of miR-674. Moreover, we found that SGK1 protein levels increased in trauma rats and SGK1 expression inhibition alleviated HPA axis abnormality post-surgery. EA could improve the number of hypothalamus iba-1 positive cells and hypothalamic interleukin 1 beta protein expression.

CONCLUSIONS

Our study demonstrated the involvement of the hypothalamic Gas5/miRNA-674/SGK1 signaling pathway in EA regulation of HPA axis function after trauma.

Multiple Traditional Chinese Medicine interventions for idiopathic pulmonary fibrosis: A protocol for systematic review and meta-analysis of overview

BACKGROUND

The therapeutic strategies of idiopathic pulmonary fibrosis (IPF) tend to be comprehensive. Improving the major symptoms and quality of life (QoL) is as important as postponing the process of fibrosis. However, only pirfenidone and nintedanib conditionally recommended by guidelines and no definite proof indicate that they can significantly ameliorate the main symptoms and QoL of IPF sufferers. At present, multiple types of Traditional Chinese Medicine (TCM) interventions alone or in combination with conventional western medicine managements are widespreadly applied in IPF treatment, which seemingly have a promising clinical effect, especially in ameliorating the main symptoms and improving QoL. Subsequently, the number of relevant studies in systematic reviews(SRs) and meta-analyses of randomized controlled trials(RCTs) increased significantly. Hence, we plan to implement an overview to collect, evaluate, and summarize the results of these SRs.

METHODS

An all-round literature retrieval will be conducted in 9 electronic databases, including PubMed, EMBASE, CINAHL, Cochrane Library, Epistemonikos, CNKI, CBM, Wanfang, and VIP. We will focus on the systematic review and meta-analysis of RCTs for multiple TCM interventions alone or in combination with routine western medicine measures in IPF treatment. The main outcomes we follow with interest include the improvement of major symptoms (cough, dyspnea) and QoL. Secondary outcomes will consist of minor symptoms improvement, clinical total effective rate, lung function, blood gas analysis, 6-minute walk text, adverse events, acute exacerbation, all-cause mortality, and IPF-related mortality. Two reviewers will independently select the SRs satisfactory with the enrolling criteria, extract key characteristics, and datas on predefined form, evaluate methodological quality by AMSTAR-2, ROBIS and PRISMA tools, and the quality of evidences adopting GRADE method. In case of any divergence will be reached an agreement by discussion or adjudicated by a third senior reviewer. We will perform a narrative synthesis of the proofs from SRs included.

RESULTS

The findings of this overvew will be presented at relevant conferences and submitted for peer-review publication.

CONCLUSIONS

We expect to obtain comprehensive and reliable evidence of IPF treated by diversified TCM interventions from the potential standard SRs, which may provide suggestions for future RCTs and SRs.

REGISTRATION NUMBER

INPLASY 202080110.

Developmental Timing Determines the Protective Effect of Maternal Electroacupuncture on Perinatal Nicotine Exposure-Induced Offspring Lung Phenotype

Introduction. Environmental exposure of the developing offspring to cigarette smoke or nicotine is an important predisposing factor for many chronic respiratory conditions, such as asthma, emphysema, pulmonary fibrosis, and so forth, in the exposed offspring. Studies showed that electroacupuncture (EA) applied to maternal "Zusanli" (ST36) acupoints during pregnancy and lactation protects against perinatal nicotine exposure- (PNE-) induced lung damage. However, the most effective time period, that is, prenatal vs. postnatal, to attain this effect has not been determined.

OBJECTIVE

To determine the most effective developmental timing of EA's protective effect against PNE-induced lung phenotype in the exposed offspring.

METHODS

Pregnant rats were given (1) saline ("S" group); (2) nicotine ("N" group); (3) nicotine + EA, exclusively prenatally ("Pre-EA" group); (4) nicotine + EA, exclusively postnatally ("Post-EA," group); and (5) nicotine + EA, administered both prenatally and postnatally ("Pre- and Post-EA" group). Nicotine was injected once daily (1 mg/kg, 100 μl) and EA was administered to bilateral ST36 acupoints once daily during the specified time-periods. At the end of the experimental periods, key hypothalamic pituitary adrenal (HPA) axis markers in pups and dams, and lung function, morphometry, and the central molecular markers of lung development in the offspring were determined.

RESULTS

After nicotine exposure, alveolar mean linear intercept (MLI) increased, but mean alveolar number (MAN) decreased and lung PPARγ level decreased, but glucocorticoid receptor (GR) and serum corticosterone (Cort) levels increased, in line with the known PNE-induced lung phenotype. In the nicotine exposed group, maternal hypothalamic corticotropin releasing hormone (CRH) level decreased, but pituitary adrenocorticotropic hormone (ACTH) and serum Cort levels increased. In the "Pre- and Post-EA" groups, PNE-induced alterations in lung morphometry, lung development markers, and HPA axis were blocked. In the "Pre-EA" group, PNE-induced changes in lung morphometry, GR, and maternal HPA axis improved; lung PPARγ level decreased, but glucocorticoid receptor (GR) and serum corticosterone (Cort) levels increased, in line with the known PNE-induced lung phenotype. In the nicotine exposed group, maternal hypothalamic corticotropin releasing hormone (CRH) level decreased, but pituitary adrenocorticotropic hormone (ACTH) and serum Cort levels increased. In the "Pre- and Post-EA" groups, PNE-induced alterations in lung morphometry, lung development markers, and HPA axis were blocked. In the "Pre-EA" group, PNE-induced changes in lung morphometry, GR, and maternal HPA axis improved; lung PPAR.

CONCLUSIONS

Maternal EA applied to ST36 acupoints during both pre- and postnatal periods preserves offspring lung structure and function despite perinatal exposure to nicotine. EA applied during the "prenatal period" affords only limited benefits, whereas EA applied during the "postnatal period" is ineffective, suggesting that the EA's effects in modulating PNE-induced lung phenotype are limited to specific time-periods during lung development.

Comparison of Protective Effects of Electroacupuncture at ST 36 and LU 5 on Pulmonary and Hypothalamic Pituitary Adrenal Axis Changes in Perinatal Nicotine-Exposed Rats

BACKGROUND

Maternal smoking and/or exposure to environmental tobacco smoke continue to be significant factors in fetal and childhood morbidity and are a serious public health issue worldwide. Nicotine passes through the placenta easily with minimal biotransformation, entering fetal circulation, where it results in many harmful effects on the developing offspring, especially on the developing respiratory system.

OBJECTIVES

Recently, in a rat model, electroacupuncture (EA) at maternal acupoints ST 36 has been shown to block perinatal nicotine-induced pulmonary damage; however, the underlying mechanism and the specificity of ST 36 acupoints for this effect are unknown. Here, we tested the hypothesis that compared with EA at ST 36, EA at LU 5 acupoints, which are on lung-specific meridian, will be equally or more effective in preventing perinatal nicotine-induced pulmonary changes.

METHODS

Twenty-four pregnant rat dams were randomly divided into 4 groups: saline ("S"), nicotine ("N"), nicotine + ST 36 (N + ST 36), and nicotine + LU 5 (N + LU 5) groups. Nicotine (1 mg/kg, subcutaneously) and EA (at ST 36 or LU 5 acupoints, bilaterally) were administered from embryonic day 6 to postnatal day 21 once daily. The "S" group was injected saline. As needed, using ELISA, western analysis, q-RT-PCR, lung histopathology, maternal and offspring hypothalamic pituitary adrenal axes, offspring key lung developmental markers, and lung morphometry were determined.

RESULTS

With nicotine exposure, alveolar count decreased, but mean linear intercept and septal thickness increased. It also led to a decrease in pulmonary function and PPARγ and an increase of β-catenin and glucocorticoid receptor expression in lung tissue and corticosterone in the serum of offspring rats. Electroacupuncture at ST 36 normalized all of these changes, whereas EA at LU 5 had no obvious effect.

CONCLUSION

Electroacupuncture applied to ST 36 acupoints provided effective protection against perinatal nicotine-induced lung changes, whereas EA applied at LU 5 acupoints was ineffective, suggesting mechanistic specificity and HPA axis' involvement in mediating EA at ST 36 acupoints' effects in mitigating perinatal nicotine-induced pulmonary phenotype. This opens the possibility that other acupoints, besides ST 36, can have similar or even more robust beneficial effects on the developing lung against the harmful effect of perinatal nicotine exposure. The approach proposed by us is simple, cheap, quick, easy to administer, and is devoid of any significant side effects.

Targeting cell signaling in allergic asthma

Asthma is chronic inflammation of the airways characterized by airway hyper-responsiveness, wheezing, cough, and dyspnea. Asthma affects >350 million people worldwide. The Th2 immune response is a major contributor to the pathophysiology of asthma. Targeted therapy modulating cell signaling pathways can be a powerful strategy to design new drugs to treat asthma. The potential molecular pathways that can be targeted include IL-4-IL-13-JAK-STAT-MAP kinases, adiponectin-iNOS-NF-κB, PGD2-CRTH2, IFNs-RIG, Wnt/β-catenin-FAM13A, FOXC1-miR-PI3K/AKT, JNK-Gal-7, Nrf2-ROS, Foxp3-RORγt, CysLTR, AMP, Fas-FasL, PTHrP/PPARγ, PAI-1, FcɛRI-LAT-SLP-76, Tim-3-Gal-9, TLRs-MyD88, PAR2, and Keap1/Nrf2/ARE. Therapeutic drugs can be designed to target one or more of these pathways to treat asthma.

Recent advances in our understanding of the mechanisms of lung alveolarization and bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most common cause of morbidity and mortality in preterm infants. A key histopathological feature of BPD is stunted late lung development, where the process of alveolarization-the generation of alveolar gas exchange units-is impeded, through mechanisms that remain largely unclear. As such, there is interest in the clarification both of the pathomechanisms at play in affected lungs, and the mechanisms of de novo alveoli generation in healthy, developing lungs. A better understanding of normal and pathological alveolarization might reveal opportunities for improved medical management of affected infants. Furthermore, disturbances to the alveolar architecture are a key histopathological feature of several adult chronic lung diseases, including emphysema and fibrosis, and it is envisaged that knowledge about the mechanisms of alveologenesis might facilitate regeneration of healthy lung parenchyma in affected patients. To this end, recent efforts have interrogated clinical data, developed new-and refined existing-in vivo and in vitro models of BPD, have applied new microscopic and radiographic approaches, and have developed advanced cell-culture approaches, including organoid generation. Advances have also been made in the development of other methodologies, including single-cell analysis, metabolomics, lipidomics, and proteomics, as well as the generation and use of complex mouse genetics tools. The objective of this review is to present advances made in our understanding of the mechanisms of lung alveolarization and BPD over the period 1 January 2017-30 June 2019, a period that spans the 50th anniversary of the original clinical description of BPD in preterm infants.

The impact of perinatal nicotine exposure on fetal lung development and subsequent respiratory morbidity

Maternal smoking during pregnancy remains as a significant public health crisis as it did decades ago. Although its prevalence is decreasing in high-income countries, it has worsened globally, along with a concerning emergence of electronic-cigarette usage within the last two decades. Extensive epidemiologic and experimental evidence exists from both human and animal studies, demonstrating the detrimental long-term pulmonary outcomes in the offspring of mothers who smoke during pregnancy. Even secondhand and thirdhand smoke exposure to the developing lung might be as or even more harmful than firsthand smoke exposure. Furthermore, these effects are not limited only to the exposed progeny, but can also be transmitted transgenerationally. There is compelling evidence to support that the majority of the effects of perinatal smoke exposure on the developing lung, including the transgenerational transmission of asthma, is mediated by nicotine. Nicotine exposure induces cell-specific molecular changes in lungs, which offers a unique opportunity to prevent, halt, and/or reverse the resultant damage through targeted molecular interventions. Experimentally, the proposed interventions, such as administration of peroxisome proliferator-activated receptor gamma (PPARγ) agonists can not only block but also potentially reverse the perinatal nicotine exposure-induced respiratory morbidity in the exposed offspring. However, the development of a safe and effective intervention is still many years away. In the meantime, electropuncture at specific acupoints appears to be emerging as a more practical and safe physiologic approach to block the harmful pulmonary consequences of perinatal nicotine exposure.