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Alcohol and nicotine are routinely abused together. There is one plausible explanation that comorbidity can alleviate alcohol-induced cognitive impairment. However, the mechanism involved is not known. The aim of this report was to evaluate the interactive effects of alcohol coadministration with nicotine on hippocampal memory and long-term potentiation (LTP). C57BL/6 mice were distributed into 4 treatment groups: control, alcohol, nicotine, and alcohol plus nicotine. All mice received tap water or alcohol solution and saline or nicotine. In water maze test, the alcohol group showed significant decreases in hippocampus function and acquisition training than control, nicotine, and combined treatment groups. The alcohol group also showed a significantly shorter latency in entering the foot-shock compartment than control, nicotine, and combined treatment groups in a passive avoidance test. Theta burst stimulation was adopted to induce concrete LTP in CA1 field recording using hippocampal slice. Alcohol alone administration failed to maintain LTP. Nicotine alone administration did not alter hippocampal LTP. There were no negative effects of alcohol on hippocampal LTP in mice administrated with nicotine. The current study successfully demonstrated beneficial effects of nicotine on alcohol induced memory impairment accompanied by hippocampal LTP impairment after one week of co-administration and one-day withdrawal.

Problem Chorioamnionitis is caused by a bacterial infection that ascends from the vagina and can cause adverse pregnancy outcomes (APOs). Fusobacterium nucleatum (F. nucleatum) is a periodontal pathogen associated with the occurrence of APOs. In this study, we evaluated whether receptor-interacting protein kinase 2 (Ripk2), an adaptor protein of the cytosolic receptors nucleotide-binding oligomerization domain (NOD)1 and NOD2, in macrophages and human decidual stromal cells (hDSCs) contributes to immune responses against F. nucleatum. Method of study Bone marrow-derived macrophages (BMDMs) isolated from wild-type (WT) and Ripk2-deficient mice and hDSCs were cultured with F. nucleatum (MOI 1, 10, 100). BMDMs and hDSCs were assessed using enzyme-linked immunosorbent assay, Western blot analysis, real-time PCR, and nitrite assay. Results Fusobacterium nucleatum-induced production of IL-6, but not of TNF-α and IL-10, was lower in Ripk2-deficient BMDMs than in WT cells. Western blotting revealed a decrease in F. nucleatum-induced p65 phosphorylation in Ripk2-deficient macrophages, whereas mitogen-activated protein kinases activation was comparable between WT and Ripk2-deficient cells. The production of nitric oxide (NO) in response to F. nucleatum and the gene and protein expression of inducible NO synthase was impaired in Ripk2-deficient BMDMs. In hDSCs, F. nucleatum upregulated the gene and protein expression of NOD1, NOD2, and Ripk2 in a time-dependent manner. F. nucleatum also increased the production of IL-6, CXCL8, and CCL2, whereas this production was decreased by the Ripk2 inhibitors SB203580 and PP2. Conclusions In conclusion, Ripk2 signaling appears to contribute to the F. nucleatum-induced immune response and can be a preventive and therapeutic target against APOs.

Endometriosis is a chronic gynecological disorder, characterized by the presence of ectopic endometrial tissue outside the uterine cavity. Among several hypotheses, Sampson's theory of retrograde menstruation is still applicable. Recent studies have reported the importance of inflammation among endometrial tissue, the peritoneum, and immune cells. However, less is known regarding the role of bacterial infection in the pathophysiology of endometriosis. We hypothesized that Ureaplasma urealyticum infection might contribute to the development of endometriosis by inducing the production of inflammatory mediators by peritoneal mesothelial cells (PMCs), possibly through TLR2. Hence, our objective was to reveal whether PMC infection by U. urealyticum is associated with endometriosis. Moreover, we aimed to demonstrate the molecular mechanism involved in this relationship. We developed a new infection-induced mouse model of endometriosis with wild type and Tlr2-deficient mice. Based on the in vivo mouse model, U. urealyticum-infected mice showed significantly increased numbers and sizes of ectopic endometriotic lesions. U. urealyticum upregulated not only the production of IL-6, CXCL1, and CCL2, but also the expression of ICAM-1, VCAM-1, and MMP2 in murine PMCs. Similarly, endometrial stromal cells dose-dependently produced IL-6, CXCL1, and CCL2 in response to U. urealyticum infection. The series of inflammatory responses in PMCs was mediated mainly through TLR2. The phosphorylation of ERK and JNK was observed when U. urealyticum was added to PMCs and knock out of Tlr2 inhibited these MAPKs phosphorylation. Based on our co-culture study, U. urealyticum-infected PMCs exhibited significantly increased attachment to ESCs compared with uninfected PMCs. Collectively, U. urealyticum infection promotes the development of endometriosis by increasing inflammatory mediators, adhesion molecules, and MMP-2 expression in PMCs through TLR2 signaling. Through our results, we present a theory that infection-induced pelvic inflammation contributes to the initiation and progression of endometriosis. Appropriate treatment of reproductive tract infection may decrease the prevalence of endometriosis.

Probiotics such as lactobacilli and bifidobacteria have healthpromoting effects by immune modulation. In the present study, we examined the immunomodulatory properties of Lactobacillus curvatus WiKim38, which was newly isolated from baechu (Chinese cabbage) kimchi. The ability of L. curvatus WiKim38 to induce cytokine production in bone marrow-derived dendritic cells (BMDCs) was determined by enzyme-linked immunosorbent assay. To evaluate the molecular mechanisms underlying L. curvatus Wikim38-mediated IL-10 production, Western blot analyses and inhibitor assays were performed. Moreover, the in vivo anti-inflammatory effects of L. curvatus WiKim38 were examined in a dextran sodium sulfate (DSS)-induced colitis mouse model. L. curvatus WiKim38 induced significantly higher levels of IL-10 in BMDCs compared with that induced by LPS. NF-κB and ERK were activated by L. curvatus WiKim38, and an inhibitor assay revealed that these pathways were required for L. curvatus WiKim38-induced production of IL-10 in BMDCs. An in vivo experiment showed that oral administration of L. curvatus WiKim38 increased the survival rate of mice with DSS-induced colitis and improved clinical signs and histopathological severity in colon tissues. Taken together, these results indicate that L. curvatus Wikim38 may have health-promoting effects via immune modulation, and may thus be applicable for therapy of various inflammatory diseases.

Mycobacterium abscessus is a prominent cause of pulmonary infection in immunosuppressed patients and those with cystic fibrosis. Nucleotide-binding oligomerization domain (NOD) 2 is a cytosolic receptor which senses a bacterial peptidoglycan component, muramyl dipeptide (MDP). Although nucleotide-binding oligomerization domain 2 (NOD2) contributes to protect host against various microbial infections, it is still unclear whether NOD2 is essential to regulate host immune responses against M. abscessus infection. In this study, we sought to clarify the role of NOD2 and the underlying mechanism in host defense against M. abscessus infection. Mice were infected intranasally with M. abscessus and sacrificed at indicated time points. Bacterial survival, cytokines production, and pathology in the lungs were determined. Bone marrow-derived macrophages were used to clarify cellular mechanism of NOD2-mediated immune response. Bacterial clearance was impaired, and pathology was more severe in the lungs of NOD2-deficient mice compared with the wild-type mice. In macrophages, NOD2-mediated activation of p38 and JNK were required for production of proinflammatory cytokines and nitric oxide (NO) and expression of iNOS in response to M. abscessus. NO was critical for limiting intracellular growth of the pathogen. Intranasal administration of MDP reduced in vivo bacterial replication and thus improved lung pathology in M. abscessus-infected mice. This study offers important new insights into the potential roles of the NOD2 in initiating and potentiating innate immune response against M. abscessus pulmonary infection.

Periodontitis is a progressive chronic inflammatory disease and a major cause of tooth loss in humans. As a withanolides, withaferin A (WA) is known to exhibit strong anti‑inflammatory activity. The present study examined whether WA inhibited inflammatory responses in macrophages in response to two representative periodontal pathogens, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans. Murine bone marrow‑derived macrophages (BMDMs) were used in this study and cytokine production in culture supernatants was measured by enzyme‑linked immunosorbent assays. Western blot analysis was performed to determine the activation of nuclear factor‑κB and mitogen‑activated protein kinases (MAPKs) and the expression of inducible nitric oxide synthase (iNOS), toll‑like receptor (TLR) 2 and TLR4. The production of nitric oxide (NO) was determined by the Griess reaction. WA treatment was shown to decrease interleukin (IL)‑6 and tumor necrosis factor (TNF)‑α production in BMDMs in response to F. nucleatum and A. actinomycetemcomitans in a dose‑dependent manner. The phosphorylation of IκB‑α and MAPKs (p38, extracellular signal‑regulated kinases and c‑Jun N‑terminal kinases) induced by F. nucleatum and A. actinomycetemcomitans was also inhibited by WA. F. nucleatum and A. actinomycetemcomitans induced iNOS expression and NO production in BMDMs, which was inhibited by WA in a dose‑dependent manner. WA also reduced endogenous and induced expression of TLR2 and TLR4 in these cells. These results suggest that WA may be a potential therapeutic agent or preventive additive for periodontitis control.