Tobacco and Nervous System Development and Function-New Findings 2015-2020

Tobacco is a one of the most common addictive stimulants used by people around the world. The smoke generated during tobacco combustion is a toxic mixture of more than 5000 chemicals of which over 30 are known human carcinogens. While its negative effects on the human body are well understood, it remains a serious public health problem. One of the multiple effects of smoking is tobacco’s effect on the nervous system—its development and function. This review aims to summarize the progress made in research on the effects of tobacco on the nervous system both of the perinatal period and adults and both in animals and humans in 2015–2020. The 1245 results that corresponded to the keywords “tobacco, cigarette, nervous system, brain, morphology, function” were reviewed, of which 200 abstracts were considered significant. Most of those articles broadened the knowledge about the negative effects of smoking on the human nervous system. Tobacco has a significant negative impact on the development of nervous structures, neurotransmission and cognitive functions, and promotes the development of neurodegenerative diseases, insomnia and cerebrovascular diseases. The only exception is the protective effect of the dopaminergic system in Parkinson’s disease. In conclusion, in recent years much effort has been devoted to describing, revealing and uncovering new aspects of tobacco detrimental to human life. The nicotine contained in tobacco smoke affects the human body in a multidimensional way, including a serious impact on the broadly understood neurological health.

This is not a pipe - But how harmful is electronic cigarette smoke

This issue of the Biomedical Journal tells us about the risks of electronic cigarette smoking, variations of SARS-CoV-2 and ACE2, and how COVID-19 affects the gastrointestinal system. Moreover, we learn that cancer immunotherapy seems to work well in elderly patients, how thyroid hormones regulate noncoding RNAs in a liver tumour context, and that G6PD is a double-edged sword of redox signalling. We also discover that Perilla leaf extract could inhibit SARS-CoV-2, that artificial neural networks can diagnose COVID-19 patients and predict vaccine epitopes on the Epstein-Barr Virus, and that men and women have differential inflammatory responses to physical effort. Finally, the surgical strategies for drug-resistant epilepsy, computer-supervised double-jaw surgery, dental pulp stem cell motility, and the restitution of the brain blood supply after atherosclerotic stroke are discussed.

Tobacco Use and Periodontal Disease-The Role of Microvascular Dysfunction

Periodontal disease consists in highly prevalent wide-ranging inflammatory conditions that affect the supporting apparatus of teeth. Tobacco use is the most important risk factor for periodontal disease as it increases disease severity and periodontal surgery complications. Tobacco use is harmful for the vasculature by causing microvascular dysfunction, which is known to negatively affect periodontal disease. To the author's knowledge this paper is the first comprehensive review on the mechanisms by which tobacco use affects oral microcirculation and impacts the pathophysiology of periodontal disease. In healthy subjects, acute nicotine administration or tobacco use (smoking/smokeless forms) increases the blood flow in the oral mucosa due to local irritation and increased blood pressure, which overcome neural- and endocrine-mediated vasoconstriction. Chronic tobacco smokers display an increased gingival microvascular density, which is attributed to an increased capillary recruitment, however, these microcirculatory units show higher tortuosity and lower caliber. These morphological changes, together with the repetitive vasoconstrictive insults, contribute to lower gingival perfusion in chronic smokers and do not completely regress upon smoking cessation. In periodontal disease there is considerable gingival inflammation and angiogenesis in non-smokers which, in chronic smokers, are considerably suppressed, in part due to local immune suppression and oxidative stress. Tobacco exposure, irrespective of the form of use, causes long-term microvascular dysfunction that increases the risk of complications due to the natural disease course or secondary therapeutic strategies.

The Impact of Substance Use Disorder on COVID-19 Outcomes

OBJECTIVE

The goal of this study was to examine the impact of substance use disorder on the risk of hospitalization, complications, and mortality among adult patients diagnosed as having COVID-19.

METHODS

The authors conducted a propensity score (PS)-matched double-cohort study (N=5,562 in each cohort) with data from the TriNetX Research Network database to identify 54,529 adult patients (≥18 years) diagnosed as having COVID-19 between February 20 and June 30, 2020.

RESULTS

Primary analysis (PS matched on demographic characteristics and presence of diabetes and obesity) showed that substance use disorder was associated with an increased risk of hospitalization (odds ratio [OR]=1.84, 95% confidence interval [CI]=1.69-2.01), ventilator use (OR=1.45, 95% CI=1.22-1.72), and mortality (OR=1.30, 95% CI=1.08-1.56).

CONCLUSIONS

The findings suggest that COVID-19 patients with substance use disorders are at increased risk for adverse outcomes. The attenuation of ORs in the model that matched for chronic respiratory and cardiovascular diseases associated with substance abuse suggests that the observed risks may be partially mediated by these conditions.

Astragalin Inhibits Cigarette Smoke-Induced Pulmonary Thrombosis and Alveolar Inflammation and Disrupts PAR Activation and Oxidative Stress-Responsive MAPK-Signaling

Epidemiological evidence shows that smoking causes a thrombophilic milieu that may play a role in the pathophysiology of chronic obstructive pulmonary disease (COPD) as well as pulmonary thromboembolism. The increased nicotine level induces a prothrombotic status and abnormal blood coagulation in smokers. Since several anticoagulants increase bleeding risk, alternative therapies need to be identified to protect against thrombosis without affecting hemostasis. Astragalin is a flavonoid present in persimmon leaves and green tea seeds and exhibits diverse activities of antioxidant and anti-inflammation. The current study investigated that astragalin attenuated smoking-induced pulmonary thrombosis and alveolar inflammation. In addition, it was explored that molecular links between thrombosis and inflammation entailed protease-activated receptor (PAR) activation and oxidative stress-responsive mitogen-activated protein kinase (MAPK)-signaling. BALB/c mice were orally administrated with 10-20 mg/kg astragalin and exposed to cigarette smoke for 8 weeks. For the in vitro study, 10 U/mL thrombin was added to alveolar epithelial A549 cells in the presence of 1-20 µM astragalin. The cigarette smoking-induced the expression of PAR-1 and PAR-2 in lung tissues, which was attenuated by the administration of ≥10 mg/kg astragalin. The oral supplementation of ≥10 mg/kg astragalin to cigarette smoke-challenged mice attenuated the protein induction of urokinase plasminogen activator, plasminogen activator inhibitor-1and tissue factor, and instead enhanced the induction of tissue plasminogen activator in lung tissues. The astragalin treatment alleviated cigarette smoke-induced lung emphysema and pulmonary thrombosis. Astragalin caused lymphocytosis and neutrophilia in bronchoalveolar lavage fluid due to cigarette smoke but curtailed infiltration of neutrophils and macrophages in airways. Furthermore, this compound retarded thrombin-induced activation of PAR proteins and expression of inflammatory mediators in alveolar cells. Treating astragalin interrupted PAR proteins-activated reactive oxygen species production and MAPK signaling leading to alveolar inflammation. Accordingly, astragalin may interrupt the smoking-induced oxidative stress-MAPK signaling-inflammation axis via disconnection between alveolar PAR activation and pulmonary thromboembolism.

Nicotine exacerbates atherosclerosis through a macrophage-mediated endothelial injury pathway

Evidence suggests that nicotine intake promotes atherosclerosis. We enrolled 100 patients with coronary heart disease (CHD) and found that plaque burden, TXNIP expression, and inflammatory chemokine levels were higher in smokers than non-smokers. Additionally, patients with higher TXNIP expression in peripheral blood mononuclear cells (PBMCs) had a higher Gensini Scores and higher plasma IL-1β and IL-18 levels. Treating bone marrow-derived macrophages (BMDMs) with nicotine in vitro led to enhanced lipid phagocytosis, chemotaxis, and increased production of reactive oxygen species (ROS), which activated TXNIP/NLRP3 inflammasome signaling and promoted pyroptosis, as evidenced by caspase-1 cleavage and increased production of IL-1β, IL-18, and gasdermin D. Nicotine intake by ApoE(-/-) mice fed a high-fat diet recapitulated those phenotypes. The effects of nicotine on pyroptotic signaling were reversed by N-acetyl-cysteine, a ROS scavenger. Silencing TXNIP in vivo reversed the effects of nicotine on macrophage invasion and vascular injury. Nicotine also induced pyroptotic macrophages that contributed to the apoptotic death of endothelial cells. These findings suggest that nicotine accelerates atherosclerosis in part by promoting macrophage pyroptosis and endothelial damage. Therefore, targeting the TXNIP/NLRP3-mediated pyroptotic pathway in macrophages may ameliorate nicotine-induced endothelial damage.

Potential Role of Melatonin as an Adjuvant for Atherosclerotic Carotid Arterial Stenosis

Carotid artery stenosis (CAS) is an atherosclerotic disease characterized by a narrowing of the artery lumen and a high risk of ischemic stroke. Risk factors of atherosclerosis, including smoking, hypertension, hyperglycemia, hyperlipidemia, aging, and disrupted circadian rhythm, may potentiate atherosclerosis in the carotid artery and further reduce the arterial lumen. Ischemic stroke due to severe CAS and cerebral ischemic/reperfusion (I/R) injury after the revascularization of CAS also adversely affect clinical outcomes. Melatonin is a pluripotent agent with potent anti-inflammatory, anti-oxidative, and neuroprotective properties. Although there is a shortage of direct clinical evidence demonstrating the benefits of melatonin in CAS patients, previous studies have shown that melatonin may be beneficial for patients with CAS in terms of reducing endothelial damage, stabilizing arterial plaque, mitigating the harm from CAS-related ischemic stroke and cerebral I/R injury, and alleviating the adverse effects of the related risk factors. Additional pre-clinical and clinical are required to confirm this speculation.

Molecular Imaging of Inflammatory Disease

Inflammatory diseases include a wide variety of highly prevalent conditions with high mortality rates in severe cases ranging from cardiovascular disease, to rheumatoid arthritis, to chronic obstructive pulmonary disease, to graft vs. host disease, to a number of gastrointestinal disorders. Many diseases that are not considered inflammatory per se are associated with varying levels of inflammation. Imaging of the immune system and inflammatory response is of interest as it can give insight into disease progression and severity. Clinical imaging technologies such as computed tomography (CT) and magnetic resonance imaging (MRI) are traditionally limited to the visualization of anatomical information; then, the presence or absence of an inflammatory state must be inferred from the structural abnormalities. Improvement in available contrast agents has made it possible to obtain functional information as well as anatomical. In vivo imaging of inflammation ultimately facilitates an improved accuracy of diagnostics and monitoring of patients to allow for better patient care. Highly specific molecular imaging of inflammatory biomarkers allows for earlier diagnosis to prevent irreversible damage. Advancements in imaging instruments, targeted tracers, and contrast agents represent a rapidly growing area of preclinical research with the hopes of quick translation to the clinic.

Effects of a dammarane-type saponin, ginsenoside Rd, in nicotine-induced vascular endothelial injury

BACKGROUND

Panax notoginseng (Burk.) F.H. Chen is a traditional medicinal plant widely used to prevent and treat cardiovascular diseases. Ginsenoside Rd (GRd) is a major bioactive component of P. notoginseng, but specific effects on cardiovascular disease-related pathogenic processes are rarely studied, especially vascular endothelial injury.

PURPOSE

This study investigated the potential protective efficacy of GRd against nicotine-induced vascular endothelial cell injury, disruption of vascular nitric oxide (NO) signaling, aberrant endothelium-monocyte adhesion, platelet aggregation, and vasoconstriction.

STUDY DESIGN/METHODS

Vascular endothelial injury and functional disruption were investigated in cultured human umbilical vein endothelial cells (HUVECs) by biochemical assays for nitric oxide (NO) and angiotensin II (Ang II), immunofluorescence (IF) and western blotting for expression analyses of apoptosis- related proteins, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), Ang II type receptor 1 (AGTR1), toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor-kappa B (NF-κB). In addition, vascular protection by GRd was examined in nicotine-administered Sprague-Dawley (SD) rats by serum NO and Ang II assays, and by hematoxylin-eosin (HE) and immunostaining of aorta. We also examined effects of GRd on monocyte (THP-1 cells) adhesion assays, adenosine diphosphate (ADP)-induced platelet aggregation, and phenylephrine (PE)-induced vasoconstriction of isolated rat aortic rings.

RESULTS

In HUVECs, nicotine significantly suppressed NO production, enhanced Ang II production, downregulated eNOS expression, and upregulated expression levels of AGTR1, TLR4, MyD88, NF-κB, iNOS, Bax/Bcl-2 ratio, cleaved caspase-3, and cytochrome c (cyt c). All of these changes were significantly reversed by GRd. In rats, oral GRd reversed the reduction NO and enhanced Ang II production in serum induced by nicotine administration, and HE staining revealed protection of aortic endothelial cells. In addition, GRd reversed nicotine-mediated enhancement of HUVECs-monocyte adhesion, inhibited ADP-induced platelet aggregation and PE-induced vasoconstriction.

CONCLUSION

GRd may prevent nicotine-induced cardiovascular diseases by preserving normal vascular endothelial NO signaling, suppressing platelet aggregation and vasoconstriction, and by preventing endothelial cell-monocyte adhesion.

Postoperative pancreatic fistula after gastrectomy for gastric cancer

Postoperative pancreatic fistula is one of the most severe complications after gastric cancer surgery, and can cause critical patient conditions leading to surgery-related death. Fortunately, the incidence of postoperative pancreatic fistula after gastrectomy seems to be decreasing with changes in operative procedures. The rate was reported at about 30% after open gastrectomy with Appleby's method in 1997, but lately has improved below 1% for robotic gastrectomy in 2019. For the diagnosis of postoperative pancreatic fistula, drain amylase concentration has been demonstrated to be beneficial and some reports have proposed the optimal cut-off values of drain amylase to predict major postoperative pancreatic fistula. There have been many reports identifying risk factors for postoperative pancreatic fistula, including overweight patients, pancreatic anatomy, blunt trauma from compression of the pancreas, and thermal injuries caused by the continuous use of energy devices. And importantly, laparoscopic gastrectomy has been shown to be more often associated with postoperative pancreatic fistula than open gastrectomy in the prospective national clinical database in Japan. Hence, further sophistication of surgical techniques to reduce pancreas compression would have great promise in reducing postoperative pancreatic fistula after laparoscopic gastrectomy.

The Effects of E-Cigarette Vapor Components on the Morphology and Function of the Male and Female Reproductive Systems: A Systematic Review

E-cigarettes, a comparatively new phenomenon, are regarded as a safer alternative to conventional cigarettes. They are increasingly popular among adolescents of both sexes, and many smokers use e-cigarettes in their attempts to quit smoking. There is little understanding of the effects of exposure to e-cigarette vapors on human reproductive health, human development, or the functioning of the organs of the male and female reproductive systems. Data on the effects of the exposure were derived mainly from animal studies, and they show that e-cigarettes can affect fertility. Here, we review recent studies on the effects of exposure to e-cigarettes on facets of morphology and function in the male and female reproductive organs. E-cigarettes, even those which are nicotine-free, contain many harmful substances, including endocrine disruptors, which disturb hormonal balance and morphology and the function of the reproductive organs. E-cigarettes cannot be considered a completely healthy alternative to smoking. As is true for smoking, deleterious effects on the human reproductive system from vaping are likely, from the limited evidence to date.

Protective effect of the medicinal herb infusion "horchata" against oxidative damage in cigarette smokers: An ex vivo study

Cigarette smoking has been associated with an increase in oxidative stress (OS) and is considered a predisposing factor to chronic noncommunicable diseases, whilst dietary antioxidants has been proposed as an alternative to cope with this oxidative stress. In this study, 20 smokers and 20 non-smokers were studied with the aim of determining their antioxidant status, as well as the ability of an infusion of 23 medicinal plants, to counteract the damage caused by OS. The plasma, red blood cells (RBCs) and polymorphonuclear cells (PBMCs) of both groups were incubated or not with the horchata infusion extract and then the OS markers, genotoxicity, nanostructure of RBCs membrane and genes related to oxidative responses and cellular functionality were evaluated. Up to 33 different compounds, mainly quercetin glycosides, were identified in the extract. A significant deterioration in the antioxidant status in smokers compared to non-smokers was found. The horchata infusion extract improved the nanostructure of RBCs and DNA damage, as well as the activity of the endogenous antioxidant enzymes and markers of oxidative damage to lipid, and proteins in plasma, RBCs and PBMCs in both groups, whilst no significant changes were found in the expression of different genes related to OS response.