Association between E-Cigarette Smoking and Insulin Resistance Using the Triglyceride-Glucose Index in Korean Adults: Korea National Health and Nutrition Examination Survey.

Background: Insulin resistance contributes to the development of cardiovascular disease and type 2 diabetes mellitus. Smoking leads to an increase in triglyceride levels, which, in turn, increases insulin resistance. Although the number of e-cigarette users has increased in recent years, few studies have investigated the association between ecigarette use and insulin resistance. Therefore, this study aimed to determine the association between e-cigarette use and insulin resistance using the triglyceride-glucose (TyG) index in Korean adults. Methods: This study included 4,404 healthy adults aged ≥20 years who participated in the Korea National Health and Nutrition Examination Survey between 2019 and 2020. Participants were categorized as never-smokers or ecigarette users, and the TyG index was categorized into low- and high-TyG index groups according to the median value (9.22). A logistic regression analysis was performed to determine the association between e-cigarette smoking and insulin resistance. Results: E-cigarette users had a higher TyG index than never smokers (e-cigarette: mean=3.95; never: mean=9.18; P<0.001). The e-cigarette users had a higher risk of being in the high TyG index group than never-smokers (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.03-1.84). In the subgroup analysis stratified by sex, age, and body mass index, a higher OR for a high TyG index was observed in men (OR, 1.46; 95% CI, 1.03-2.08) and individuals aged 60 years or older (OR, 3.74; 95% CI, 1.14-12.30). Conclusion: Our findings suggest that e-cigarette use is significantly associated with insulin resistance.

Del-1, an Endogenous Inhibitor of TGF-ß Activation, Attenuates Fibrosis.

Uncontrolled activation of transforming growth factor (TGF)-ß results in a wide range of pathologic conditions. Therapeutic interventions to regulate TGF-ß signaling during fibrosis have been developed but the effectiveness is still limited. Here, we show that developmental endothelial locus-1 (Del-1) ameliorates fibrosis in mice by inhibiting αv integrin-mediated activation of TGF-ß. Del-1 bound to αvß6 integrin, an important activator of TGF-ß, and inhibited the binding of αvß6 integrin to the latency-associated peptide (LAP), thereby suppressing αv integrin-mediated activation of TGF-ß. Lack of Del-1 increased colocalization of αv integrin and LAP in the lungs, which was reversed by Del-1 supplementation. The crucial role of Del-1 in regulating TGF-ß activity was recapitulated in a mouse model of fibrosis using an adenovirus expressing inactive TGF-ß1. Del-1 supplementation improved the pathological characteristics of the mice and reduced mortality. Thus, we propose that Del-1 is a negative regulator of TGF-ß activation and a potential anti-fibrotic factor.

Developmental endothelial locus-1 prevents development of peritoneal adhesions in mice.

Postoperative peritoneal adhesions, fibrous bands formed in the peritoneal cavity following surgery, represent a common, challenging and costly problem faced by surgeons and patients, for which effective therapeutic options are lacking. Since aberrant inflammation is one of the key mechanisms underlying peritoneal adhesion formation, here we set out to study the role of developmental endothelial locus-1 (Del-1), which has been recently identified as an endogenous inhibitor of inflammation, in the formation of postoperative peritoneal adhesions using a mouse model of peritoneal adhesions induced by ischemic buttons. Del-1-deficient mice had a higher incidence of adhesions, and their adhesions had higher quality and tenacity scores. Del-1 deficiency also led to enhanced inflammation mediators and collagen production. Finally, Del-1 supplementation decreased the incidence and severity of postoperative peritoneal adhesions. Taken together, these results indicate a protective role for Del-1 in postoperative peritoneal adhesion formation.

p-Coumaric Acid, a Major Active Compound of Bambusae Caulis in Taeniam, Suppresses Cigarette Smoke-Induced Pulmonary Inflammation.

[Formula: see text]-coumaric acid ([Formula: see text]-CA) is a common compound found in medicinal herbs, including Bambusae Caulis in Taeniam (BC). It has been used to treat various diseases in China and Korea. Our previous study demonstrated that BC inhibits pulmonary and intestinal inflammation. In the present study, we used cigarette smoke (CS) to induce lung inflammation in vivo, and investigated the anti-inflammatory effects of [Formula: see text]-CA on CS-induced inflammatory mice model. Mice were treated with BC and [Formula: see text]-CA via oral injection 2[Formula: see text]h before CS exposure. The body weight and the inflammatory cells in the bronchoalveolar lavage fluid were measured. The levels of relative inflammatory factors were confirmed by enzyme-linked immunosorbent assay. The lung histological changes were examined by hematoxylin and eosin staining. Also, the protein level of nuclear factor-[Formula: see text]B (NF-[Formula: see text]B) was evaluated by Western blotting. Our results indicated that BC and [Formula: see text]-CA inhibited CS-induced lung inflammation by regulating pro-inflammatory productions such as cytokines, chemokine, protease and NF-[Formula: see text]B. Consequently, these data demonstrated that [Formula: see text]-CA inhibited pulmonary inflammation by suppressing NF-[Formula: see text]B activity, through which pro-inflammatory mediators were regulated. Therefore, [Formula: see text]-CA, which was shown to be a major component of BC, can be considered as a strong therapeutic candidate for treating pulmonary inflammatory diseases.

Macrophage Depletion Protects against Cigarette Smoke-Induced Inflammatory Response in the Mouse Colon and Lung.

Cigarette smoke (CS) is considered as a major risk factor for pulmonary and intestinal inflammation. CS leads to macrophage infiltration in the mucosae of the lung and colon, inducing the uncontrolled secretion of inflammatory mediators, and thus promoting inflammatory response. In this study, we investigated whether macrophage depletion modulates cigarette smoke (CS)-induced inflammatory response in both the lung and colon. The mice were exposed to CS for 30 min, after which they were rested in a fresh air environment for 30 min. The total duration of exposure to CS was 2 h per day for 4 weeks. Macrophage depletion state was made with the injection of clodronate containing liposome. Individual body weights were measured twice a week, and the mice were sacrificed on day 28. Hematoxylin and eosin (H&E) staining was performed in the lung and colon tissue to determine histological changes. Inflammatory mediators' synthesis was analyzed using ELISA and western blotting. Clodronate liposome treatment ameliorated pathological changes associated with the infiltration of immune cells in the lung and colon. Also, clodronate liposome injected mice showed significantly lower level of inflammatory mediators, including cytokines and chemokine and proteases. Our results indicated that macrophage depletion by clodronate liposome treatment attenuates CS-induced inflammatory response in both the lung and colon.

Original Research: Extract of Bambusae Caulis in Taeniam inhibits cigarette smoke-induced pulmonary and intestinal inflammation.

The pulmonary and intestinal systems have several characteristics in common. It is believed that these similarities somehow function to cause pulmonary-intestinal crosstalk during inflammation. Many studies have shown that pulmonary disease occurs in association with inflammatory bowel disease more often than is commonly recognized. Bambusae Caulis in Taeniam, a medicinal herb originated from the inner bark of Phyllostachys nigra var. henosis (Milford) Rendle (Poaceae), has been used to cure fever, diarrhea, and chest inflammation in Korea as well as in China. Cigarette smoke is a well-known risk factor for several inflammatory disorders. In this study, we induced pulmonary and bowel inflammation in mice using cigarette smoke and investigated whether Bambusae Caulis in Taeniam extract modulates the inflammatory response in both the lung and the bowel. C57BL/6 mice were exposed to cigarette smoke for 90 min per day for three weeks, and Bambusae Caulis in Taeniam extract was administered via oral injection 2 h before cigarette smoke exposure. The bronchoalveolar lavage cells were counted and hematoxylin and eosin staining were performed. Levels of inflammatory mediators in lung and large intestine were determined by enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and Western blotting. Our results showed that Bambusae Caulis in Taeniam attenuated cigarette smoke-induced inflammatory response in both the lung and the bowel of mice by inhibiting the production of pro-inflammatory cytokines, chemokines, and protease as well as NF-κB signaling factor. Therefore, we suggest that Bambusae Caulis in Taeniam extract might be a candidate therapeutic agent for inhibiting pulmonary and intestinal inflammation.

Sceptridium ternatum attenuates allergic contact dermatitis-like skin lesions by inhibiting T helper 2-type immune responses and inflammatory responses in a mouse model.

BACKGROUND: Sceptridium ternatum (ST) is a medicinal herb used in folk remedies for the treatment of various disorders such as pertussis, allergic asthma, abdominalgia, diarrhea, and external use for wound healing. However, the biological and pharmacological activities of ST are not fully clarified besides anti-asthmatic effect. OBJECTIVE: We studied a Sceptridium ternatum ethanol extract (ST) with respect to its anti-inflammatory and immune regulatory activities in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, concanavalin A (conA)-stimulated BALB/c mice splenocytes, and a 2,4-dinitrochlorobenzene (DNCB)-induced allergic contact dermatitis (ACD) mouse model. METHODS: RAW 264.7 cells were pretreated with ST for 1h and then stimulated with LPS. To determine the anti-inflammatory effects of ST, the production of nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) were measured using an enzyme-linked immunosorbent assay (ELISA). To determine its anti-allergic effects, splenocytes from BALB/c mice were incubated and stimulated with conA in the absence or presence of ST for 48h. The production of IL-4 and interferon (IFN)-γ in culture supernatants were evaluated by ELISA. To test the effects of ST on ACD, 100µL of 1% DNCB was applied to the dorsal skin of BALB/c mice for 2 weeks, and ST was administered 2 h before DNCB application. The thicknesses of the epidermis and dermis were determined by skin histological analysis. Serum immunoglobulin (Ig) E levels, the production of IL-1ß, IL-4, and IL-6 in dorsal skin tissue, and T helper (Th) 2 cytokines production of CD4(+) T cells were analyzed by ELISA. The expression of nuclear transcription factor-κB (NF-κB) both in vitro and in vivo was determined via immunoblotting. RESULTS: In RAW 264.7 cells, ST inhibited LPS-induced inflammation mediator production and NF-κB expression. ST upregulated IFN-γ production and downregulated IL-4 production in conA-stimulated splenocytes. ST application reduced the thicknesses of the epidermis and dermis by decreasing serum IgE level and the expressions of IL-1ß, IL-4, IL-6, and NF-κB in the dorsal skin of the DNCB-induced ACD model mice. Furthermore, ST treated group showed reduction of the Th2 cytokines production in activated CD4(+) T cells. CONCLUSION: These findings not only indicate that application of ST reduced skin thickening by regulating Th 2-type allergic responses and inhibiting expression of inflammatory mediators in a DNCB-induced ACD mouse model, but also suggest that Sceptridium ternatum is a natural option for the treatment of skin inflammation.

Stemona tuberosa prevented inflammation by suppressing the recruitment and the activation of macrophages in vivo and in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Stemona tuberosa (ST) is a traditional herbal medicine used for the treatment of various respiratory diseases in eastern Asia. AIM OF THE STUDY: We investigated the anti-inflammatory effects of a ST water extract in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and in cigarette smoke (CS)-induced lung inflammation mouse models. MATERIALS AND METHODS: RAW 264.7 macrophages were treated with the ST extract and stimulated by LPS. The expressions of pro-inflammatory mediators were evaluated by using nitric oxide (NO) assay, enzyme-linked immunosorbent assay and Western blot analysis. After the C57BL/6 mice were exposed to CS, they were administrated with the ST extract. The accumulated inflammatory cells in the bronchoalveolar lavage fluid (BALF) were counted. Also, real-time polymerase chain reaction and hematoxylin and eosin staining were performed in lung tissues. RESULTS: The ST extract treatment reduced the production of NO via blocking the expressions of cyclooxygenase-2 and inducible nitric oxide synthase protein in RAW 264.7 macrophages. In addition, ST extract treatment decreased the secretions of inflammatory cytokines and regulated NF-κB activation by inhibiting the phosphorylation of IκB and the mitogen-activated protein kinase pathway. Also, ST extract administration to mice reduced the infiltrations of macrophages into BALF and the histological inflammatory changes in lung tissues. Furthermore, administration of the ST extract regulated the levels of tumor necrosis factor-α, interleukin (IL)-6, IL-1ß, monocyte chemoattractant protein-1 and matrix metalloproteinases-12 in the lungs. CONCLUSION: These findings suggested that ST extract attenuated pulmonary inflammatory responses by inhibiting the expression of diverse inflammatory mediators in vivo and in vitro.

Galla Chinensis attenuates cigarette smoke-associated lung injury by inhibiting recruitment of inflammatory cells into the lung.

Inflammation is a common feature in the pathogenesis of cigarette smoke (CS)-associated diseases. In this study, we investigated the effects of Galla Chinensis (GC) extract on pulmonary inflammatory responses in a CS-exposed mouse model. In vitro studies showed that GC extract reduced MCP-1 production in a dose-dependent manner. In addition, the recruitment of inflammatory cells into the lung was significantly inhibited in the bronchoalveolar lavage fluid (BALF) of the GC-treated mice after 3 weeks of daily CS exposure. GC treatment down-regulated TNF-α, IL-6 and MCP-1 mRNA expression levels in lung tissue. Finally, GC-treated mice showed less emphysematous change of alveolar compared to mice only exposed to CS. Our results show that GC extract reduces lung inflammation and emphysematous change by inhibiting the infiltration of inflammatory cells to the lung. These data indicate that GC extract is a therapeutic candidate for CS-induced lung injury.