Metformin ameliorates chronic colitis in a mouse model by regulating interferon-γ-producing lamina propria CD4+ T cells through AMPK activation.

Metformin, a commonly prescribed drug for type 2 diabetes mellitus, has been shown to activate AMP-activated protein kinase (AMPK). Notably, AMPK activation has recently been observed to be associated with anti-inflammatory responses. Metformin is also reported to elicit anti-inflammatory responses in CD4+ T cells, resulting in improvement in experimental chronic inflammatory diseases, such as systemic lupus erythematosus. To investigate the effect of metformin on inflammatory bowel disease (IBD), we developed a T cell-transfer model of chronic colitis in which SCID mice were injected with CD4+ CD45RBhigh T cells to induce colitis. We examined the effects of metformin via in vitro and in vivo experiments on lamina propria (LP) CD4+ T cells. We observed that metformin suppresses the frequency of interferon (IFN) -γ-producing LP CD4+ T cells in vitro, which were regulated by AMPK activation, a process possibly induced by the inhibition of oxidative phosphorylation. Furthermore, we examined the effects of metformin on an in vivo IBD model. Metformin-treated mice showed AMPK activation in LP CD4+ T cells and ameliorated colitis. Our study demonstrates that metformin-induced AMPK activation in mucosal CD4+ T cells contributes to the improvement of IBD by suppressing IFN-γ production. Moreover, our results indicate that AMPK may be a target molecule for the regulation of mucosal immunity and inflammation. Thus, AMPK-activating drugs such as metformin may be potential therapeutic agents for the treatment of IBD.

The possible protective role of N-acetyl cysteine on duodenal mucosa of high fat diet and orlistat treated adult male albino rats and the active role of tumor necrosis factor α (TNFα) and Interleukin 6 (IL6) (histological and biochemical study).

BACKGROUND: Obesity is a major universal health issue linked to a majority of illness. AIM: To evaluate the histological and biochemical changes occurred in the duodenal mucosa of high fat diet HFD and orlistat fed rats and to assess the possible protective role of N-acetyl cysteine NAC supplementation. MATERIAL AND METHOD: Sixty male albino rats weighing 180-200 g were classified randomly into control group I and three experimental groups (HFD group II, HFD + orlistat group III, and HFD + orlistat + NAC group IV). All experimental groups received HFD alone/and treatment for 6 weeks. Group III received orlistat (32 mg/kg/day) before meals and group IV received the same regimen as group III in addition to NAC (230 mg/kg/day) after meals. After completion of the experiment, duodenal sections were processed for histological examination, oxidative stress parameters, and semiqualitative real time PCR for proinflammatory mediators TNFα and IL6 evaluation. Also, plasma lipid parameters were assessed and morphometric duodenal results were analyzed statistically. RESULTS: By histological examination of HFD and (HFD + orlistat) groups, we found severe to moderate duodenal structural disturbances, increased goblet cells, collagen fibers, and BAX and iNOS immunostaining. By Biochemical examination, both groups showed increased proinflammatory markers level (TNFα and IL6) with decreased all antioxidant parameters and increased MDA. Moreover, NAC treatment in group IV significantly reduced all structural changes, levels of proinflammatory mediators and increased all antioxidant parameter levels and decreased MDA. CONCLUSION: All findings elucidated that NAC could be accounted to be a useful drug for protection of duodenal mucosa of HFD and orlistat treated animals.

Changes in Eustachian Tube Mucosa in Mice After Short-Term Tobacco and E-cigarette Smoke Exposure.

OBJECTIVES: To evaluate histologic changes in middle ear and eustachian tube (ET) mucosa of mice after exposure to tobacco or electronic cigarette (e-cigarette) smoke. To determine whether there were any mitigating effects of middle ear application of anti-IL-13 or the epidermal growth factor receptor antagonist AG1478 on noted changes within ET mucosa. STUDY DESIGN: Controlled animal study. METHODS: Fifty BALB/cJ mice were randomly assigned to one of five groups: A control group with no smoke exposure, two groups exposed to tobacco smoke, and two groups exposed to e-cigarette vapor. Within the exposed groups after 4 weeks of exposure, one ear was infiltrated with a saline hydrogel and the other ear with hydrogel of either Anti-IL-13 or AG1478. After four more weeks of exposure, the animals were euthanized and the ETs were evaluated for mucosal changes. RESULTS: Compared to control animals with no smoke exposure, there were significant decreases in the numbers of goblet cells within the ET mucosa of mice exposed to tobacco smoke and e-cigarette vapor. No significant differences in cilia, mucin, or squamous metaplasia were noted. Neither anti-IL-13 nor AG178 significantly altered goblet cell count in the ET mucosa of mice exposed to tobacco smoke; however, both agents significantly increased goblet cells within the ET mucosa of mice exposed to e-cigarette vapor. CONCLUSION: Short-term tobacco smoke and e-cigarette vapor significantly decrease goblet cell count in mouse ET mucosa. Middle ear application of both anti-IL-13 and AG1478 resulted in an increase in goblet cell count among mice exposed to e-cigarette vapor, but not to tobacco smoke. LEVEL OF EVIDENCE: NA Laryngoscope, 132:648-654, 2022.

Repeated Low-Dose Acrolein Triggers Irreversible Lamina Propria Edema in Urinary Bladder, Transient Voiding Behavior and Widening of Eyes to Mechanical Stimuli.

Acrolein is a metabolite of cyclophosphamide (CYP), an alkylating agent used for a wide range of benign and malignant diseases. CYP treatments are known to trigger hemorrhagic cystitis in patients and animals. Significant effort has been made to prevent CYP/acrolein-induced cystitis, while still maintaining its therapeutic benefits. As a result, supplementary therapeutic options to mediate the protective role against CYP/acrolein and lower doses of CYP are currently given to targeted patients, as compared to past treatments. There is still a need to further study the effects of the repeated low-dose CYP/acrolein on the pathophysiology of the urinary bladder. In our study, a one-time treatment of acrolein and repeated low-dose acrolein triggered the thickening of the smooth muscle and lamina propria in the urinary bladder of C57BL/6J mice, respectively. The first dose of acrolein did not trigger voiding dysfunction, but the second dose triggered high-volume low-frequency voiding. Interestingly, our new scoring criteria and concurrent behavioral assessment revealed that mice with repeated low-dose acrolein had a wider opening of eyes in response to mechanical stimuli. Our study suggests that clinical symptoms among patients undergoing prolonged low-dose CYP may differ from previously reported symptoms of CYP-induced hemorrhagic cystitis.

Native CGRP Neuropeptide and Its Stable Analogue SAX, But Not CGRP Peptide Fragments, Inhibit Mucosal HIV-1 Transmission.

Background: The vasodilator neuropeptide calcitonin gene-related peptide (CGRP) plays both detrimental and protective roles in different pathologies. CGRP is also an essential component of the neuro-immune dialogue between nociceptors and mucosal immune cells. We previously discovered that CGRP is endowed with anti-viral activity and strongly inhibits human immunodeficiency virus type 1 (HIV-1) infection, by suppressing Langerhans cells (LCs)-mediated HIV-1 trans-infection in-vitro and mucosal HIV-1 transmission ex-vivo. This inhibition is mediated via activation of the CGRP receptor non-canonical NFκB/STAT4 signaling pathway that induces a variety of cooperative mechanisms. These include CGRP-mediated increase in the expression of the LC-specific pathogen recognition C-type lectin langerin and decrease in LC-T-cell conjugates formation. The clinical utility of CGRP and modalities of CGRP receptor activation, for inhibition of mucosal HIV-1 transmission, remain elusive. Methods: We tested the capacity of CGRP to inhibit HIV-1 infection in-vivo in humanized mice. We further compared the anti-HIV-1 activities of full-length native CGRP, its metabolically stable analogue SAX, and several CGRP peptide fragments containing its binding C-terminal and activating N-terminal regions. These agonists were evaluated for their capacity to inhibit LCs-mediated HIV-1 trans-infection in-vitro and mucosal HIV-1 transmission in human mucosal tissues ex-vivo. Results: A single CGRP intravaginal topical treatment of humanized mice, followed by HIV-1 vaginal challenge, transiently restricts the increase in HIV-1 plasma viral loads but maintains long-lasting higher CD4+ T-cell counts. Similarly to CGRP, SAX inhibits LCs-mediated HIV-1 trans-infection in-vitro, but with lower potency. This inhibition is mediated via CGRP receptor activation, leading to increased expression of both langerin and STAT4 in LCs. In contrast, several N-terminal and N+C-terminal bivalent CGRP peptide fragments fail to increase langerin and STAT4, and accordingly lack anti-HIV-1 activities. Finally, like CGRP, treatment of human inner foreskin tissue explants with SAX, followed by polarized inoculation with cell-associated HIV-1, completely blocks formation of LC-T-cell conjugates and HIV-1 infection of T-cells. Conclusion: Our results show that CGRP receptor activation by full-length CGRP or SAX is required for efficient inhibition of LCs-mediated mucosal HIV-1 transmission. These findings suggest that formulations containing CGRP, SAX and/or their optimized agonists/analogues could be harnessed for HIV-1 prevention.

Temporal Changes in Vaginal Microbiota and Genital Tract Cytokines Among South African Women Treated for Bacterial Vaginosis.

The standard treatment for bacterial vaginosis (BV) with oral metronidazole is often ineffective, and recurrence rates are high among African women. BV-associated anaerobes are closely associated with genital inflammation and HIV risk, which underscores the importance of understanding the interplay between vaginal microbiota and genital inflammation in response to treatment. In this cohort study, we therefore investigated the effects of metronidazole treatment on the vaginal microbiota and genital cytokines among symptomatic South African women with BV [defined as Nugent score (NS) ≥4] using 16S rRNA gene sequencing and multiplex bead arrays. Among 56 BV-positive women, we observed short-term BV clearance (NS <4) in a proportion of women six weeks after metronidazole treatment, with more than half of these experiencing recurrence by 12 weeks post-treatment. BV treatment temporarily reduced the relative abundance of BV-associated anaerobes (particularly Gardnerella vaginalis and Atopobium vaginae) and increased lactobacilli species (mainly L. iners), resulting in significantly altered mucosal immune milieu over time. In a linear mixed model, the median concentrations of pro-inflammatory cytokines and chemokines were significantly reduced in women who cleared BV compared to pre-treatment. BV persistence and recurrence were strongly associated with mucosal cytokine profiles that may increase the risk of HIV acquisition. Concentrations of these cytokines were differentially regulated by changes in the relative abundance of BVAB1 and G. vaginalis. We conclude that metronidazole for the treatment of BV induced short-term shifts in the vaginal microbiota and mucosal cytokines, while treatment failures promoted persistent elevation of pro-inflammatory cytokine concentrations in the genital tract. These data suggest the need to improve clinical management of BV to minimize BV related reproductive risk factors.

Tetramethylpyrazine Alleviates Tight Junction Disruption of Bronchial Mucosal Epithelial Cells Caused by Interleukin-17 via Inhibiting Nuclear Factor-κB-p65/Tumor Necrosis Factor-α Signaling Pathway.

Bronchial mucosal epithelial dysregulation and barrier disruption are involved in the initiation and development of acute lung injury (ALI). Some inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-17 (IL-17) contribute to the pathological changes of ALI. However, the roles and relationship between TNF-α and IL-17 during the disruption of bronchial epithelial tight junction remain unclear. Tetramethylpyrazine (TMP) is confirmed to have beneficial functions in hemostasis, inflammation, and cell growth. Here, we demonstrated the protective effects of TMP on bronchial mucosal epithelial injury induced by IL-17. We showed that IL-17 stimulation in vitro markedly reduced occludin and zonula occludens-1 (ZO-1) expression in bronchial mucosal epithelial cells via the nuclear factor-κB-p65/TNF-α signaling pathway, including NF-κB-p65-triggered TNF-α gene transcription and expression. TMP obviously rescued IL-17-induced occludin and ZO-1 downregulation. Mechanically, TMP substantially suppressed NF-κB-p65 activation and NF-κB-p65-induced TNF-α production in bronchial mucosal epithelial cells caused by IL-17. Taken together, this study indicates that TMP has a protective effect on bronchial mucosal epithelial cell injury due to IL-17 induction by inhibiting the NF-κB-p65/TNF-α signaling pathway.

Real-world efficacy and safety of axitinib in combination with anti-programmed cell death-1 antibody for advanced mucosal melanoma.

PURPOSE: The combination of vascular endothelial growth factor receptor (VEGFR) inhibitor and programmed cell death-1 (PD-1) blockade provides promising therapeutic opportunities for advanced mucosal melanoma in early phase trials. The aim of this retrospective study was to evaluate the efficacy and safety of the combination regimen for advanced mucosal melanoma in the real world. METHODS: Patients with advanced mucosal melanoma received an anti-PD-1 antibody plus the VEGFR inhibitor axitinib until confirmed disease progression or unacceptable toxicity. In addition, those with liver metastasis were allowed to take hepatic transcatheter arterial chemoembolisation (TACE). The primary endpoint was overall response rate (ORR). Secondary endpoints included disease control rate (DCR), time to treatment failure (TTF), duration of response (DOR), overall survival (OS) and treatment-related adverse events (TRAEs). RESULTS: Eighty-one and sixty-six patients received axitinib plus immunotherapy as first-line and salvage therapy, respectively. Overall, ORR was 24.5% (95% CI, 17.3-31.6), DCR was 72.7% (95% CI, 65.3-80.1). Median TTF, DOR and OS were 5.2 months (95% CI, 3.7-6.6), 9.2 months (95% CI, 7.2-11.2) and 11.1 months (95% CI, 7.2-15.0). ORR was 30.0% (95% CI, 19.7-40.3) and 17.5% (95% CI, 7.8-27.1) as first-line and salvage therapy, respectively. No statistical difference among the primary sites was noted for ORR. The ORR of patients with liver metastasis with or without hepatic TACE was 26.1% (95% CI, 6.7-45.5) and 15.0% (95% CI, 2.1-32.1), respectively (P = 0.467). Elevated LDH and poor ECOG status are negative predictive factors. CONCLUSION: This is the largest analysis of anti-PD-1 plus VEGFR inhibitor therapy for mucosal melanoma to date. Immunotherapy plus anti-angiogenesis is applicable for advanced mucosal melanoma, especially as front-line. Hepatic TACE might act synergistically with systemic immunotherapy and anti-angiogenesis.

High-Resolution Quantitative Mapping of Macaque Cervicovaginal Epithelial Thickness: Implications for Mucosal Vaccine Delivery.

Vaginal mucosal surfaces naturally offer some protection against sexually transmitted infections (STIs) including Human Immunodeficiency Virus-1, however topical preventative medications or vaccine designed to boost local immune responses can further enhance this protection. We previously developed a novel mucosal vaccine strategy using viral vectors integrated into mouse dermal epithelium to induce virus-specific humoral and cellular immune responses at the site of exposure. Since vaccine integration occurs at the site of cell replication (basal layer 100-400 micrometers below the surface), temporal epithelial thinning during vaccine application, confirmed with high resolution imaging, is desirable. In this study, strategies for vaginal mucosal thinning were evaluated noninvasively using optical coherence tomography (OCT) to map reproductive tract epithelial thickness (ET) in macaques to optimize basal layer access in preparation for future effective intravaginal mucosal vaccination studies. Twelve adolescent female rhesus macaques (5-7kg) were randomly assigned to interventions to induce vaginal mucosal thinning, including cytobrush mechanical abrasion, the chemical surfactant spermicide nonoxynol-9 (N9), the hormonal contraceptive depomedroxyprogesterone acetate (DMPA), or no intervention. Macaques were evaluated at baseline and after interventions using colposcopy, vaginal biopsies, and OCT imaging, which allowed for real-time in vivo visualization and measurement of ET of the mid-vagina, fornices, and cervix. P value ≤0.05 was considered significant. Colposcopy findings included pink, rugated tissue with variable degrees of white-tipped, thickened epithelium. Baseline ET of the fornices was thinner than the cervix and vagina (p<0.05), and mensing macaques had thinner ET at all sites (p<0.001). ET was decreased 1 month after DMPA (p<0.05) in all sites, immediately after mechanical abrasion (p<0.05) in the fornix and cervix, and after two doses of 4% N9 (1.25ml) applied over 14 hrs in the fornix only (p<0.001). Histological assessment of biopsied samples confirmed OCT findings. In summary, OCT imaging allowed for real time assessment of macaque vaginal ET. While varying degrees of thinning were observed after the interventions, limitations with each were noted. ET decreased naturally during menses, which may provide an ideal opportunity for accessing the targeted vaginal mucosal basal layers to achieve the optimum epithelial thickness for intravaginal mucosal vaccination.

Development, Characterization, and Evaluation of SLN-Loaded Thermoresponsive Hydrogel System of Topotecan as Biological Macromolecule for Colorectal Delivery.

BACKGROUND: Chemotherapeutic drugs cause severe toxicities if administered unprotected, without proper targeting, and controlled release. In this study, we developed topotecan- (TPT-) loaded solid lipid nanoparticles (SLNs) for their chemotherapeutic effect against colorectal cancer. The TPT-SLNs were further incorporated into a thermoresponsive hydrogel system (TRHS) (TPT-SLNs-TRHS) to ensure control release and reduce toxicity of the drug. Microemulsion technique and cold method were, respectively, used to develop TPT-SLNs and TPT-SLNs-TRHS. Particle size, polydispersive index (PDI), and incorporation efficiency (IE) of the TPT-SLNs were determined. Similarly, gelation time, gel strength, and bioadhesive force studies of the TPT-SLNs-TRHS were performed. Additionally, in vitro release and pharmacokinetic and antitumour evaluations of the formulation were done. RESULTS: TPT-SLNs have uniformly distributed particles with mean size in nanorange (174 nm) and IE of ~90%. TPT-SLNs-TRHS demonstrated suitable gelation properties upon administration into the rat's rectum. Moreover, drug release was exhibited in a control manner over an extended period of time for the incorporated TPT. Pharmacokinetic studies showed enhanced bioavailability of the TPT with improved plasma concentration and AUC. Further, it showed significantly enhanced antitumour effect in tumour-bearing mice as compared to the test formulations. CONCLUSION: It can be concluded that SLNs incorporated in TRHS could be a potential source of the antitumour drug delivery with better control of the drug release and no toxicity.

Erythritol Ameliorates Small Intestinal Inflammation Induced by High-Fat Diets and Improves Glucose Tolerance.

BACKGROUND: Erythritol, a sugar alcohol, is widely used as a substitute for sugar in diets for patients with diabetes or obesity. METHODS: In this study, we aimed to investigate the effects of erythritol on metabolic disorders induced by a high-fat diet in C57BL/6J mice, while focusing on changes in innate immunity. RESULTS: Mice that were fed a high-fat diet and administered water containing 5% erythritol (Ery group) had markedly lower body weight, improved glucose tolerance, and markedly higher energy expenditure than the control mice (Ctrl group) (n = 6). Furthermore, compared with the Ctrl group, the Ery group had lesser fat deposition in the liver, smaller adipocytes, and significantly better inflammatory findings in the small intestine. The concentrations of short-chain fatty acids (SCFAs), such as acetic acid, propanoic acid, and butanoic acid, in the serum, feces, and white adipose tissue of the Ery group were markedly higher than those in the Ctrl group. In flow cytometry experiments, group 3 innate lymphoid cell (ILC3) counts in the lamina propria of the small intestine and ILC2 counts in the white adipose tissue of the Ery group were markedly higher than those in the Ctrl group. Quantitative real-time reverse transcription polymerase chain reaction analyses showed that the Il-22 expression in the small intestine of the Ery group was markedly higher than that in the Ctrl group. CONCLUSIONS: Erythritol markedly decreased metabolic disorders such as diet-induced obesity, glucose intolerance, dyslipidemia, and fat accumulation in the mouse liver by increasing SCFAs and modulating innate immunity.

Morphogenetic Aspects of the Response of Vaginal Tissues to Polypropylene Implants as the Basis of Mesh-Associated Complications.

Morphometric and immunohistochemical examination of the vaginal mucosa before and 12 months after installation of polypropylene implants for the correction of stress urinary incontinence was performed in 20 patients with genital prolapse. The research results confirmed good biocompatibility of polypropylene and the formation of full-fledged connective tissue in the vaginal mucosa, but revealed the presence of a weak lymphocytic reaction to polypropylene 12 months after surgery. According to immunohistochemical study, increased contents of B lymphocytes and plasma cells responsible for the inductive and productive stages of the immune response were revealed in the vaginal mucosa around the implants 12 months after surgery. This reaction in the presences of provoking factors can lead to the development of inflammation and erosion, a type of mesh-associated complications.

Squalene nanoemulsion reinforces mucosal and immunological fingerprints following intravaginal delivery.

This study describes the assessment of mucosal adjuvant activity of a squalene-based nanoemulsion (SQ@NE) following intravaginal delivery in mice. After immunization, a high level of recruitment of CD11b/c+ granulocytes and F4/80+ macrophages was observed in the vaginal mucosal tissues of the mice immunized with a model protein ovalbumin (OVA) formulated with SQ@NE, and then downstream regulated the expression of MHC II and costimulatory molecules CD40 and CD86 on CD11c+ cells harvested from the associated draining lymph node. With respect to cytotoxic T lymphocyte immunity, the mice immunized with SQ@NE-formulated OVA elicited a high population of OVA-specific CD8+ cells in the spleen and increased the secretion of IFN-γ, IL-2 and IL-17 from OVA-restimulated splenocytes compared with those immunized with OVA alone. By studying in vivo fluorescence imaging and B-cell immunoassays, we discovered how SQ@NE prolongs the retention of antigen depots at the mucosal membrane of the immune inductive site and allows them to properly drive the production of antibodies. The data demonstrated that SQ@NE prolonged fluorescence-labeled OVA retention at the genital tract and augmented the production of OVA-specific IgG in sera and IgA in vaginal washes. These results indicate that SQ@NE is a promising vaginal adjuvant for the induction of both mucosal and systemic immune responses, a feature that provides implications for the development of a mucosal vaccine against genital infections and sexually transmitted diseases.

A sustained type I IFN-neutrophil-IL-18 axis drives pathology during mucosal viral infection.

Neutrophil responses against pathogens must be balanced between protection and immunopathology. Factors that determine these outcomes are not well-understood. In a mouse model of genital herpes simplex virus-2 (HSV-2) infection, which results in severe genital inflammation, antibody-mediated neutrophil depletion reduced disease. Comparative single-cell RNA-sequencing analysis of vaginal cells against a model of genital HSV-1 infection, which results in mild inflammation, demonstrated sustained expression of interferon-stimulated genes (ISGs) only after HSV-2 infection primarily within the neutrophil population. Both therapeutic blockade of IFNα/ß receptor 1 (IFNAR1) and genetic deletion of IFNAR1 in neutrophils concomitantly decreased HSV-2 genital disease severity and vaginal IL-18 levels. Therapeutic neutralization of IL-18 also diminished genital inflammation, indicating an important role for this cytokine in promoting neutrophil-dependent immunopathology. Our study reveals that sustained type I interferon (IFN) signaling is a driver of pathogenic neutrophil responses and identifies IL-18 as a novel component of disease during genital HSV-2 infection.

Herpes simplex virus (HSV) is a human pathogen that causes genital herpes, an incurable disease that results in recurrent sores and inflammation. Infection with HSV induces a strong antiviral immune response, which results in large numbers of immune cells arriving at these lesions. But while some of these cells help to control viral replication, others might contribute to the inflammation that drives the disease. One of the first immune cells to respond to infection are neutrophils. Although neutrophils are generally protective, especially against bacteria and fungi, they have also been implicated in tissue damage and severe inflammation during viral infections. But what determines whether a neutrophil will help to fight off an infection or increase disease severity is still an open question. To investigate this, Lebratti, Lim et al. studied mice that had been infected with the genital herpes virus HSV-2, which is known to cause significant amounts of inflammation in mice. The experiments revealed that a signaling molecule called type I interferon, which is thought to be antiviral, causes neutrophils at the site of the infection to produce proteins, such as IL-18, which trigger an inflammatory reaction. Lebratti, Lim et al. found that type I interferon and IL-18 had shifting roles during the course of infection. In the early stages, both molecules had a protective effect, confirming results from previous studies. However, as the infection progressed, sustained levels of type I interferon signaling in neutrophils led to excess amounts of IL-18. Lebratti, Lim et al. discovered that blocking interferon signaling or decreasing the levels of IL-18 later during infection unexpectedly reduced the severity of the disease and resulted in less genital tissue damage. Further experiments also showed that mice infected with another genital herpes virus called HSV-1 did not experience sustained levels of type I interferon. This may explain why this virus causes less severe disease in mice. Understanding how the immune system reacts to viruses could reveal new targets for treatments of genital herpes. At the moment, there is little information about IL-18 production during genital herpes in humans. So, the next step is to see whether neutrophils behave in the same way and whether IL-18 can be detected during human disease. It is possible that the same immune components could promote disease in other infections too. If so, this work may help uncover new drug targets for other viral diseases.

An updated review on the effects of depot medroxyprogesterone acetate on the mucosal biology of the female genital tract.

BACKGROUND: Access to safe, effective, and affordable contraception is important for women's health and essential to mitigate maternal and fetal mortality rates. The progestin-based contraceptive depot medroxyprogesterone acetate (DMPA) is a popular contraceptive choice with a low failure rate and convenient administration schedule. AIM: In this review, we compiled observational data from human cohorts that examine how DMPA influences the mucosal biology of the female genital tract (FGT) that are essential in maintaining vaginal health, including resident immune cells, pro-inflammatory cytokines, epithelial barrier function, and the vaginal microbiome MATERIALS AND METHODS: This review focused on the recent published literature published in 2019 and 2020. RESULTS: Recent longitudinal studies show that DMPA use associates with an immunosuppressive phenotype, increase in CD4+CCR5+ T cells, and alterations to growth factors. In agreement with previous meta-analyses, DMPA use is associated with minimal effects of the composition of the vaginal microbiome. Cross-sectional studies associate a more pro-inflammatory relationship with DMPA, but these studies are confounded by inherent weaknesses of cross-sectional studies, including differences in study group sizes, behaviors, and other variables that may affect genital inflammation. DISCUSSION & CONCLUSION: These recent results indicate that the interactions between DMPA and the vaginal mucosa are complex emphasizing the need for comprehensive longitudinal studies that take into consideration the measurement of multiple biological parameters.

Tadalafil ameliorates bladder overactivity by restoring insulin-activated detrusor relaxation via the bladder mucosal IRS/PI3K/AKT/eNOS pathway in fructose-fed rats.

The pathophysiologies of metabolic syndrome (MS) and overactive bladder (OAB) might overlap. Using fructose-fed rats (FFRs) as a rodent model of MS we investigated the effects of tadalafil (a phosphodiesterase type 5 inhibitor) on the dysregulated insulin signalling in the bladder mucosa and bladder overactivity. Micturition behaviour was evaluated. Concentration-response curves on detrusor relaxation to insulin stimulation were examined. Expression and phosphorylation of proteins in the insulin signalling pathway were evaluated by Western blotting. Levels of detrusor cGMP and urinary nitrite and nitrate (NOx) were measured. We observed FFRs exhibited metabolic traits of MS, bladder overactivity, and impaired insulin-activated detrusor relaxation in organ bath study. A high-fructose diet also impeded insulin signalling, reflected by overexpression of IRS1/pIRS1Ser307 and pIRS2Ser731 and downregulation of PI3K/pPI3KTyr508, AKT/pAKTSer473, and eNOS/peNOSSer1177 in the bladder mucosa, alongside decreased urinary NOx and detrusor cGMP levels. Tadalafil treatment restored the reduced level of mucosal peNOS, urinary NOx, and detrusor cGMP, improved the insulin-activated detrusor relaxation, and ameliorated bladder overactivity in FFRs. These results suggest tadalafil may ameliorate MS-associated bladder overactivity by restoring insulin-activated detrusor relaxation via molecular mechanisms that are associated with preservation of IR/IRS/PI3K/AKT/eNOS pathway in the bladder mucosa and cGMP production in the bladder detrusor.

Estrogen modulates epithelial progenitor cells in rat vagina.

PURPOSE: The expression of epithelial progenitor cells (EPCs) in rat vagina was recently reported. The aims were to investigate the effects of estrogen on vaginal EPCs in the oophorectomized female rat model. MATERIALS AND METHODS: Female Sprague-Dawley rats (230-240 g, n=30) were divided into 3 groups: control (n=10), bilateral oophorectomy (OVX, n=10), and bilateral OVX followed by subcutaneous injections of 17ß-estradiol (50 µg/kg/day, n=10). After 4 weeks, the expression of EPC-specific markers (CD44, estrogen receptor alpha [ERα], and progesterone receptor) were evaluated by immunohistochemistry and Western blot. RESULTS: The CD44/ERα double-labeled cells were mainly expressed in basal cell layers and suprabasal layers as shown by confocal immunofluorescence. Confocal microscopy revealed that the number of CD44+/ERα+ cells decreased in the OVX group compared with the controls but was similar to control levels in rats receiving estrogen replacements. The protein expression of CD44 and ERα decreased after OVX and was restored to control levels after estrogen supplementation. CONCLUSIONS: Markers of EPCs were expressed in the vagina, and the expression of resident EPCs was regulated by estrogen. These findings imply that resident EPCs may have an important role in the regeneration of vaginal mucosa by estrogen replacement.

The Role of the Immune Response in the Development of Medication-Related Osteonecrosis of the Jaw.

Medication-related osteonecrosis of the jaw (MRONJ) is a rare but serious adverse drug effect. There are multiple hypotheses to explain the development of MRONJ. Reduced bone remodeling and infection or inflammation are considered central to the pathogenesis of MRONJ. In recent years, increasing evidence has shown that bisphosphonates (BPs)-mediated immunity dysfunction is associated with the pathophysiology of MRONJ. In a healthy state, mucosal immunity provides the first line of protection against pathogens and oral mucosal immune cells defense against potentially invading pathogens by mediating the generation of protective immunoinflammatory responses. In addition, the immune system takes part in the process of bone remodeling and tissue repair. However, the treatment of BPs disturbs the mucosal and osteo immune homeostasis and thus impairs the body's ability to resist infection and repair from injury, thereby adding to the development of MRONJ. Here, we present the current knowledge about immunity dysfunction to shed light on the role of local immune disorder in the development of MRONJ.

EGF-mediated suppression of cell extrusion during mucosal damage attenuates opportunistic fungal invasion.

Severe and often fatal opportunistic fungal infections arise frequently following mucosal damage caused by trauma or cytotoxic chemotherapy. Interaction of fungal pathogens with epithelial cells that comprise mucosae is a key early event associated with invasion, and, therefore, enhancing epithelial defense mechanisms may mitigate infection. Here, we establish a model of mold and yeast infection mediated by inducible epithelial cell loss in larval zebrafish. Epithelial cell loss by extrusion promotes exposure of laminin associated with increased fungal attachment, invasion, and larval lethality, whereas fungi defective in adherence or filamentation have reduced virulence. Transcriptional profiling identifies significant upregulation of the epidermal growth factor receptor ligand epigen (EPGN) upon mucosal damage. Treatment with recombinant human EPGN suppresses epithelial cell extrusion, leading to reduced fungal invasion and significantly enhanced survival. These data support the concept of augmenting epithelial restorative capacity to attenuate pathogenic invasion of fungi associated with human disease.

Characterization of genetics in patients with mucosal melanoma treated with immune checkpoint blockade.

Mucosal melanoma is a rare form of melanoma which arises from melanocytes in the mucosal membranes and can be effectively treated with immune checkpoint blockade (ICB). However, response rates in mucosal melanoma are lower than those observed for cutaneous melanomas. Targeted sequencing of up to 447 genes (OncoPanel) was performed on tumors from all mucosal melanoma patients seen at the Dana-Farber Cancer Institute from 2011 until March 2019. We identified a total of 46 patients who received ICB with both tumor-genotype and ICB response data available. Within this cohort of patients, 16 (35%) had durable clinical benefit (DCB) to their first line of ICB. The average mutational burden/megabase was 6.23 and did not correlate with tumor response to ICB. Patients with KIT aberrations had a higher DCB rate compared with patients with wildtype KIT (71 vs. 28%), but this was not found to be statistically significant. For comparison, we analyzed tumor genotypes from an additional 50 mucosal melanoma tumors and 189 cutaneous melanoma tumors. The most frequent mutations in mucosal melanoma were in SF3B1 (27%), KIT (18%), and NF1 (17%), a pattern that is distinct from cutaneous melanomas. In addition, there were genetic differences observed based upon the site of origin of the mucosal melanoma. Our findings explore clinical features of response in patients with mucosal melanoma treated with ICB and demonstrate a low mutational burden that does not correlate with response. In addition, the lack of significant association between the genetic aberrations tested and response to ICB indicates the need for further exploration in this patient population.