Oxidative stress in retinal pigment epithelium impairs stem cells: a vicious cycle in age-related macular degeneration.

Aging, chronic oxidative stress, and inflammation are major pathogenic factors in the development and progression of age-related macular degeneration (AMD) with the loss of retinal pigment epithelium (RPE). The human RPE contains a subpopulation of progenitors (i.e., RPE stem cells-RPESCs) whose role in the RPE homeostasis is under investigation. We evaluated the paracrine effects of mature RPE cells exposed to oxidative stress (H2O2) on RPESCs behavior through co-cultural, morphofunctional, and bioinformatic approaches. RPESCs showed a decline in proliferation, an increase of the senescence-associated ß-galactosidase activity, the acquisition of a senescent-like secretory phenotype (SASP), and the reduction of their stemness and differentiation competencies. IL-6 and Superoxide Dismutase 2 (SOD2) seem to be key molecules in RPESCs response to oxidative stress. Our results get insight into stress-induced senescent-associated molecular mechanisms implicated in AMD pathogenesis. The presence of chronic oxidative stress in the microenvironment reduces the RPESCs abilities, inducing and/or maintaining a pro-inflammatory retinal milieu that in turn could affect AMD onset and progression.

Tissue Biomarkers Predicting Lymph Node Status in Cutaneous Melanoma.

Cutaneous melanoma is a severe neoplasm that shows early invasiveness of the lymph nodes draining the primary site, with increased risk of distant metastases and recurrence. The tissue biomarker identification could be a new frontier to predict the risk of early lymph node invasiveness, especially in cases considered by current guidelines to be at low risk of lymph node involvement and not requiring evaluation of the sentinel lymph node (SLN). For this reason, we present a narrative review of the literature, seeking to provide an overview of current tissue biomarkers, particularly vascular endothelium growth factors (VEGF), Tetraspanin CD9, lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), D2-40, and gene expression profile test (31-GEP). Among these, 31-GEP seems to be able to provide a distinction between low or high risk for positive SLN classes. VEGF receptor-3 and CD9 expression may be independent predictors of positive SLN. Lastly, LYVE-1 and D2-40 allow an easier assessment of lymph vascular invasion, which can be considered a good predictor of SLN status. In conclusion, biomarkers to assess the lymph node status of cutaneous melanoma patients may play an important role in those cases where the clinician is in doubt whether or not to perform SLN biopsy.

Tetraspanin CD9 Expression Predicts Sentinel Node Status in Patients with Cutaneous Melanoma.

The tetraspanin CD9 is considered a metastasis suppressor in many cancers, however its role is highly debated. Currently, little is known about CD9 prognostic value in cutaneous melanoma. Our aim was to analyse CD9 expression in melanocytic nevi and primary cutaneous melanomas through immunohistochemistry and immunofluorescence approaches to determine its correlation with invasiveness and metastatic potential. CD9 displayed homogeneous staining in all melanocytic nevi. In contrast, it showed a complete loss of reactivity in all thin melanomas. Interestingly, CD9 was re-expressed in 46% of intermediate and thick melanomas in small tumor clusters predominantly located at sites of invasion near or inside the blood or lymphatic vessels. The most notable finding is that all CD9 stained melanomas presented sentinel node positivity. Additionally, a direct association between CD9 expression and presence of distant metastasis was reported. Finally, we confirm that CD9 expression is consistent with an early protective role against tumorigenesis, however, our data endorse in melanoma a specific function of CD9 in vascular dissemination during late tumor progression. The presence of CD9 hotspots could be essential for melanoma cell invasion in lymphatic and endothelial vessels. CD9 could be a valid prognostic factor for lymph node metastasis risk.

Paraoxonase-2: A potential biomarker for skin cancer aggressiveness.

BACKGROUND: Cutaneous neoplasms include melanoma and non-melanoma skin cancers (NMSCs). Among NMSCs, basal cell carcinoma (BCC) represents the most common lesion. On the contrary, although accounting for less than 5% of all skin cancers, melanoma is responsible for most of cutaneous malignancy-related deaths. Paraoxonase-2 (PON2) is an intracellular enzyme exerting a protective role against production of reactive oxygen species within mitochondrial respiratory chain. Recently, a growing attention has been focused on exploring the role of PON2 in cancer. The aim of this study was to investigate the diagnostic and prognostic role of PON2 in skin neoplasms. MATERIALS AND METHODS: 36 cases of BCC, distinguished between nodular and infiltrative lesions, as well as 29 melanoma samples were analysed by immunohistochemistry to evaluate PON2 protein expression. Subsequent statistical analyses were carried out to explore the existence of correlations between intratumour enzyme levels and clinicopathological features. RESULTS: Results obtained showed PON2 overexpression in BCCs compared with controls. In particular, distinguishing between less and more aggressive tumour forms, we found no significant differences in enzyme levels between nodular BCCs and controls. Conversely, PON2 expression was significantly higher in infiltrative BCCs compared with controls. Moreover, the enzyme was strongly upregulated in melanoma samples with respect to controls. Interestingly, PON2 levels were positively correlated with Breslow thickness, Clark level, regression, mitoses, lymph node metastases, primary tumour (pT) parameter and pathological stage. CONCLUSIONS: Reported findings seem to suggest that PON2 expression levels could be positively related with tumour aggressiveness of both BCC and melanoma.

The efficacy of in vivo administration of Apremilast on mesenchymal stem cells derived from psoriatic patients.

INTRODUCTION: Psoriasis cellular hallmarks, such as the imbalance between Th1/Th17 and Th2 cytokines and the dysregulated expression of vascular endothelial growth factor (VEGF), inducible nitric oxide synthase, (iNOS) and indoleamine 2,3-dioxygenase (IDO), are all detectable in mesenchymal stem cells (MSCs) suggesting that psoriasis originates at mesenchymal level. AIM OF THE STUDY: In this scenario, MSCs may become the new therapeutic target and interest in the effects of traditionally used drugs, such as Apremilast, on MSCs has greatly increased. MATERIALS AND METHODS: MSCs from control subjects (C-MSCs) and from psoriatic patients before (PsO MSCs T0) and after in vivo treatment with Apremilast (PsO-MSCs T12) were isolated and characterized; subsequently, the effects of Apremilast on VEGF, iNOS and IDO expression were evaluated by immunocytochemistry (ICC). The expression of VEGF, iNOS and IDO was also detected in skin sections by immunohistochemistry (IHC). RESULTS: The results indicate that in vivo administration of Apremilast is able to drive the altered profile of PsO-MSCs towards a more physiological pattern. In skin sections, the role of Apremilast is evident in reducing VEGF, iNOS and IDO expression. CONCLUSION: Apremilast treatment influences the expression of VEGF, iNOS and IDO not only by keratinocytes but also by MSCs, restoring their intrinsic profile and their natural anti-inflammatory action, and decreasing the auto-inflammatory process that underpins the development of psoriasis.

New Evidence and Insights on Dalbavancin and Wound Healing in a Mouse Model of Skin Infection.

Dalbavancin is an effective antibiotic that is widely used to treat skin infection. Our aim was to determine the effect of dalbavancin administration on wound healing compared to that of vancomycin and to elucidate if epidermal growth factor receptor (EGFR), matrix metalloproteinase 1 (MMP-1), MMP-9, and vascular endothelial growth factor (VEGF) could be involved in its therapeutic mechanism. A mouse model of methicillin-resistant Staphylococcus aureus (MRSA) skin infection was established. Mice were treated daily with vancomycin (10 mg/kg) and weekly with dalbavancin at day 1 (20 mg/kg) and day 8 (10 mg/kg). After 14 days, wounds were excised, and bacterial counts were performed. Wound healing was assessed by histological and immunohistochemical staining, followed by protein extraction and immunoblotting. Our microbiological results confirmed that both dalbavancin and vancomycin are effective in reducing the bacterial load in wounds. The dalbavancin group showed a strong effect compared with infected untreated animals and the vancomycin-treated group. The wounds treated with dalbavancin showed robust epidermal coverage with reconstitution of the regular and keratinized epidermal lining and well-organized granulation tissue with numerous blood vessels, although slightly less than that in the uninfected group. While in the vancomycin-treated group the epithelium appeared, in general, still hypertrophic, the granulation tissue appeared even less organized. We observed elevated EGFR and VEGF expression in both treated groups, although it was higher in dalbavancin-treated mice. MMP-1 and MMP-9 were decreased in uninfected tissue and in both treated tissues compared with untreated infected wounds. This study showed faster healing with dalbavancin treatment that might be associated with higher EGFR and VEGF levels.

Cancer stem cell enrichment is associated with enhancement of nicotinamide N-methyltransferase expression.

The cancer stem cell theory states that a subset of tumor cells, termed cancer stem cells (CSCs), has the ability to self-renew and differentiate within the tumors. According to this theory, CSCs would be mainly responsible for tumor initiation, progression, resistance to therapy, recurrence, and metastasis. In this study, a culture system was setup to enrich CSCs from bladder cancer (T24), lung cancer (A549), colorectal cancer (CaCo-2), and osteosarcoma (MG63) cell lines, through sphere formation. Magnetic-activated cell sorting was also used to further increase CSC enrichment. Subsequently, molecular characterization of CSC-enriched cell populations and parental cells was carried out, by exploring the expression levels of stem markers and the enzyme nicotinamide N-methyltransferase (NNMT). Results obtained showed a significant upregulation of stem cell markers in CSC-enriched populations, obtained upon sphere formation, compared with parental counterparts. Moreover, NNMT expression levels were markedly increased in samples enriched with CSCs with respect to control cells. Considering the fundamental role played by CSCs in carcinogenesis, reported data strengthen the hypothesis that sustains a pivotal role of NNMT in cancer growth and metastasis. In addition, these findings could represent an important achievement for the development of new and effective anticancer therapies, based on CSC-associated targets.

Dental pulp stem cells senescence and regenerative potential relationship.

Uncomplicated treatments for pulpitis and periodontitis continues to be challenging and regenerative approaches could meet this contingency. Dental pulp stem cells (DPSCs) represent a good candidate for oral recovering therapies. Here, we investigated changes in morphology, proliferation, and in vitro differentiation toward mesenchymal and neuronal phenotypes of human DPSCs harvested from differently aged donors. Aging is a physiologic phenomenon occurring with time that hamper body's capability to maintain homeostasis also affecting the functional reserve. Cytofluorimetric, immunohistochemical, quantitative reverse-transcription polymerase chain reaction (qRT-PCR), and western blot analyses were performed to gain insight for successful regenerative strategies in elderly. We observed a decline in DPSCs proliferation and differentiation potential with age. Interestingly, these cells behaved differently under osteogenic or odontogenic stimuli, showing different age-related mineralization capabilities. Similarly, neurogenic differentiation decreased with age. In conclusion, our observations represent a valid tool for the development of tailored regenerative strategies in an aging society.

Nitric oxide synthase and VEGF expression in full-term placentas of obese women.

An adequate placental vascularization allows the proper development of the fetus and it is crucial for the gestational success. A number of factors regulate angiogenesis, including vascular endothelial growth factor (VEGF), which induces the synthesis of nitric oxide (NO), a potent vasodilator produced by three different nitric oxide synthase (NOS) isoforms. NO is essential to maintain a low vascular resistance in the fetoplacental circulation, although at high concentrations, it may combine with excess superoxide to produce peroxynitrite, which reacts with proteins giving rise to nitrotyrosine. Since obesity, whose incidence is increasing worldwide, is characterized by a low-grade inflammatory state and increased levels of oxidative and nitrative stress, both affecting placental function, our aim was to evaluate the expression of VEGF, eNOS, and iNOS in full-term placentas obtained from normal weight and pre-pregnancy obese women by means of immunohistochemistry and real-time PCR. Moreover, we assessed the NO levels and the nitrotyrosine immunoexpression in the same sample groups. Our results show a significantly higher immunohistochemical expression of VEGF and eNOS in the endothelium of placentas from obese women than in controls, whereas the immunoexpression of iNOS was comparable in the two groups. These data agree with those of the gene expression analysis, thus suggesting the possible existence of a compensatory mechanism for changes in placental blood flow associated with obesity. As concerns nitrotyrosine and NO levels, we observed a significant increase in placental tissue from obese women which may contribute to the development of metabolic and cardiovascular diseases both in the mother and the offspring.

Nicotinamide N-methyltransferase in nonmelanoma skin cancers.

BACKGROUND: Squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) represent the most common forms of nonmelanoma skin cancers (NMSCs). Although successful treatment of these neoplasms is based on surgical excision, an increasing number of BCCs relapses and many SCCs display high rates of recurrence and metastasis. Nicotinamide N-methyltransferase (NNMT) is a cytosolic enzyme, which was found to be upregulated in different solid tumours. However, there are no data regarding enzyme expression in NMSCs. The aim of this study was therefore to evaluate the potential involvement of NNMT in BCCs and SCCs. MATERIALS AND METHODS: Immunohistochemical analyses were carried out on 40 BCC cases and 39 SCC cases, to evaluate enzyme expression in tumour and surrounding healthy margins. Moreover, the relationship between NNMT intratumour levels and clinico-pathological parameters were explored. RESULTS: Nicotinamide N-methyltransferase was found to be overexpressed in BCCs compared with control tissues, while a significant enzyme downregulation was detected in SCCs with respect to corresponding healthy margins. In addition, NNMT levels were negatively related to aggressiveness of both BCCs (distinguishing between infiltrative and nodular tumours) and SCCs (considering head and neck forms and tumours of the extremities and trunk). CONCLUSIONS: These evidences seem to demonstrate that the different NNMT dysregulation detected in BCC and SCC may be the result of important biological traits distinctively characterizing these two forms within NMSCs. In addition, enzyme levels seem to be inversely correlated with tumour aggressiveness, thus suggesting the potential suitability of the enzyme as a prognostic biomarker for both neoplasms.

Allyl Isothiocyanate Exhibits No Anticancer Activity in MDA-MB-231 Breast Cancer Cells.

It was reported recently that allyl isothiocyanate (AITC) could inhibit various types of cancer cell growth. In the present study, we further investigated whether AITC could inhibit the growth of human breast cancer cells. Unexpectedly, we found that AITC did not inhibit, rather slightly promoted, the proliferation of MDA-MB-231 breast cancer cells, although it did have inhibitory effect on MCF-7 breast cancer cells. Cytofluorimetric analysis revealed that AITC (10 µM) did not induce apoptosis and cell cycle arrest in MDA-MB-231 cells. In addition, AITC significantly (p < 0.05) increased the expression of BCL-2 and mTOR genes and Beclin-1 protein in MDA-MB-231 cells. No significant changes in expression of PRKAA1 and PER2 genes, Caspase-8, Caspase-9, PARP, p-mTOR, and NF-κB p65 proteins were observed in these AITC-treated cells. Importantly, AITC displayed cytotoxic effect on MCF-10A human breast epithelial cell line. These observations suggest that AITC may not have inhibitory activity in MDA-MB-231 breast cancer cells. This in vitro study warrants more preclinical and clinical studies on the beneficial and harmful effects of AITC in healthy and cancer cells.

Correlation between immunohistochemical staining of CEACAM1 and clinicopathological findings in oral pre-neoplastic lesions and squamous cell carcinoma.

Squamous cell carcinoma of the oral cavity represents the sixth most common cancer worldwide and it is often preceded by pre-neoplastic lesions. Sometimes it is still difficult for pathologists to make objective differential diagnoses only on histological characteristics. Tumorigenesis is accompanied by altered expression of cell adhesion molecules, like carcinoembryonic antigen cell adhesion molecule (CEACAM)1. We wanted to investigative CEACAM1 in oral dysplastic lesions, carcinoma in situ (CIS) and oral squamous cell carcinoma (OSCC). We examined immunohistochemical CEACAM1 expression in 50 OSCC, 30 oral CIS and 40 pre-neoplastic lesions and assessed its correlation with clinical and pathological parameters. CEACAM1 was not expressed in normal mucosa, significantly expressed in CIS while it was negative in all the dysplastic lesions. In OSCC, high CEACAM1 expression was associated with tumor grade and inversely correlated with both overall and disease-specific 5-year survival. We showed that CEACAM1 expression is very dynamic: absent in dysplastic lesions, up-regulated in CIS and OSCC. We suggest that CEACAM1 could be a prognostic marker of OSCC and oral CIS. Our most important finding was that it could help pathologists diagnosing oral carcinoma in situ.

Role of Daptomycin on Burn Wound Healing in an Animal Methicillin-Resistant Staphylococcus aureus Infection Model.

Prolonged hospitalization and antibiotic therapy are risk factors for the development of methicillin-resistant Staphylococcus aureus (MRSA) infections in thermal burn patients. We used a rat model to study the in vivo efficacy of daptomycin in the treatment of burn wound infections by S. aureus, and we evaluated the wound healing process through morphological and immunohistochemical analysis. A copper bar heated in boiling water was applied on a paraspinal site of each rat, resulting in two full-thickness burns. A small gauze was placed over each burn and inoculated with 5 × 107 CFU of S. aureus ATCC 43300. The study included two uninfected control groups with and without daptomycin treatment, an infected control group that did not receive any treatment, and two infected groups treated, respectively, with intraperitoneal daptomycin and teicoplanin. The main outcome measures were quantitative culture, histological evaluation of tissue repair, and immunohistochemical expression of wound healing markers: epidermal growth factor receptor (EGFR) and fibroblast growth factor 2 (FGF-2). The highest inhibition of infection was achieved in the group that received daptomycin, which reduced the bacterial load from 107 CFU/ml to about 103 CFU/g (P < 0.01). The groups treated with daptomycin showed better overall healing with epithelialization and significantly higher collagen scores than the other groups, and these findings were also confirmed by immunohistochemical data. In conclusion, our results support the hypothesis that daptomycin is an important modulator of wound repair by possibly reducing hypertrophic burn scar formation.

Increase of n-NOS and i-NOS in Rat Colon After Sacral Neuromodulation.

OBJECTIVE: Sacral neuromodulation (SNM) is proposed to treat different anorectal dysfunctions but its mechanism of action is not yet known. Our previous study demonstrated how SNM can significantly increase neuronal nitric oxide synthase NOS (n-NOS) and inducible NOS (i-NOS) expression in the anus and rectum of rats. There are no reports regarding the relation between SNM and NOS in colonic cells: our aim was to assess NOS expression in colonic rat model after SNM. MATERIALS AND METHODS: Twenty-six female Sprangue-Dawley rats were considered: group I, normal control rats; group II, sham treatment rats, in whom electrodes for electrical stimulation were placed in S1 foramen bilaterally and left in place, without performing neuromodulation; group III, rats in whom SNM was performed. After 14 days, the rats were sacrificed and we evaluated n-NOS and i-NOS in colonic specimens by immunohistochemistry and Western Blot analysis. RESULTS: Western Blot analysis showed that levels of n-NOS and i-NOS were higher in colon of the III group rats respect to the others; in particular, immunohistochemistry revealed that, after neuromodulation, n-NOS expression in the muscle cells and i-NOS expression in glandular epithelium and nervous cells were highly represented (p < 0.05). CONCLUSION: Our study showed that in colon, SNM is able to influence NO synthesis, activating n-NOS expression in muscle cells and i-NOS expression in glandular epithelium and nervous cells. Our study showed a complex colonic response to SNM. This experimental model could be applied to better understand the mechanism of action of SNM in bowel dysfunction.

Glycodelin expression in pregnant patients with cervical intraepithelial neoplasia: a case-control study.

We aimed to evaluate glycodelin immunostaining in pregnant women with a first diagnosis of cervical intraephitelial neoplasia (CIN) and to correlate the expression of CIN with Ki-67 and glycodelin immunostaining. A retrospective case-control study was performed including 20 patients with natural pregnancy and with first time onset of CIN occurring not later than 16 gestational weeks. The control group included 20 non-pregnant patients matched for age, parity, smoking status and number of previous sexual partners. Exclusion criteria included previous cervical treatment, immunocompromised status and chronic hepatitis B and/or C. Staining for Glycodelin and for Ki-67 was expressed using a classification based on the distribution of positivity on a semi-quantitative three-point scale. An inverse relationship was observed between glycodelin immunostaining and CIN grade in pregnant patients (p = 0.01), with a significantly higher expression in CIN1 than in CIN2 and CIN3, but not in non-pregnant patients (p = 0.81). Positivity for Ki-67 was less intense in pregnant than in non-pregnant patients. A significant inverse relationship was observed between glycodelin immunostaining and Ki-67 expression (p = 0.02). We suggest that the higher expression of glycodelin in pregnancy is related to a lower proliferative activity in CIN, which is probably associated to hormonal status of pregnancy. Further clinical studies are needed to support these findings.

Antiangiogenic and antitumor activities of berberine derivative NAX014 compound in a transgenic murine model of HER2/neu-positive mammary carcinoma.

Berberine (BBR) is a natural isoquinoline alkaloid with proven antiangiogenic and anticancer activities. We recently demonstrated that BBR and its synthetic derivative 13-(4-chlorophenylethyl)berberine iodide, NAX014, exert antiproliferative activity against HER2-overexpressing breast cancer cells, inducing apoptosis, modulating the expression of cell cycle checkpoint molecules involved in cell senescence, and reducing both HER2 expression and phosphorylation on tumor cells. In this study, we examined the anticancer properties of BBR and NAX014 in a transgenic mouse model which spontaneously develops HER2-positive mammary tumors. Repeated intraperitoneal injections of a safety dose (2.5mg/kg) of NAX014 delayed the development of tumors, reducing both the number and size of tumor masses. In vivo sidestream dark field videomicroscopy revealed a significant lower vessel density in mammary tumors from NAX014-treated mice in comparison with the control group. Immunohistochemical evaluation using CD34 antibody confirmed the reduced vessel density in NAX014 group. Statistically significant increase of senescence associated ß-galactosidase and p16 expression, and reduced expression of heparanase were observed in tumors from NAX014-treated mice than in tumors from control animals. Finally, NAX014 treatment decreased the level of perforine and granzyme mRNA in mammary tumors. Berberine did not show any statistically significant modulation in comparison with control mice. The results of the present study indicate that NAX014 is more effective than BBR in exerting anticancer activity delaying the development of mammary tumors in mice transgenic for the HER-2/neu oncogene. The antitumor efficacy of NAX014 is mainly related to its effect on tumor vascular network and on induction of tumor cell senescence.

Is it possible to predict the need of inguinal lymphadenectomy in patients with squamous cell carcinoma of the penis? A clinical and a pathological study.

OBJECTIVE: to investigate the role of CD- 44 immunohistochemical expression within tumoural and non-tumoural tissue, aiming to understand if it can help us to predict the need of performing inguinal lymph nodes dissection to complete surgery of the penis. MATERIALS AND METHODS: CD44 immunohistochemical expression was investigated in tissue specimens from 39 patients with squamous cell carcinoma of the penis who underwent partial or total penectomy between 1987 and 2008. Patient age, tumour size, and grade; CD44 intensity score, cytological expression, topographic and distribution pattern were evaluated by immunohistochemistry on archived material and correlated with disease-specific survival. RESULTS: mean patients age was 67.7 years; mean followup was 130.44 months. Bilateral inguinal lymphadenectomy was performed in 14 patients; there were 8 N+ patients (23.5%). pTis-pT1 vs. > pT1 and the EAU classification of risk group resulted to be predictive of lymph nodal metastases at univariate analysis (respectively p = 0.006 and p = 0.045), but not the grading. The intensity score, cytological expression, topographic and distribution pattern of CD44 staining did not correlate with stage, grade and lymph nodes metastases. All disease related deaths occurred only in patients showing an high CD44 intratumoral expression, but this correlation is not statistically significant. Multivariate analysis showed that only lymph node metastasis was an independent prognostic factor predictive of lymph nodes metastases. CONCLUSIONS: CD44 expression in patients with squamous cell carcinoma of the penis is not able to predict the need of performing inguinal lymphadenectomy; staging and the EAU classification of risk group resulted to be predictive of lymph nodal metastases.

Interleukin-1ß, cyclooxygenase-2, and hypoxia-inducible factor-1α in asthenozoospermia.

Impaired male fertility may have a variety of causes, among which asthenozoospermia. In its etiology, several bioactive substances, such as cytokines may be involved. In this context, our aim was to evaluate the expression of interleukin-1ß, cyclooxygenase-2, and hypoxia-inducible factor-1α, in spermatozoa isolated from normospermic fertile donors and asthenozoospermic infertile patients. We evaluated twenty-eight infertile patients affected by idiopathic asthenozoospermia and twenty-three normospermic fertile donors, age-matched. Sperm parameters were evaluated; immunohistochemical analysis and enzyme-linked immunosorbent assay were then performed in isolated spermatozoa. Spermatozoa from the asthenozoospermic group presented an increased expression of IL-1ß, COX-2, and HIF-1α compared with the normospermic fertile subjects. Our results can lead us to speculate that the increased expression of these substances may influence sperm motility. Nevertheless, further studies are needed in order to assess whether these bioactive mediators have a potential relevance as targets in future therapeutic strategies for the treatment of male infertility.

ER-mitochondria association negatively affects wound healing by regulating NLRP3 activation.

Methicillin-resistant Staphylococcus aureus (MRSA) is the most common causative agent of acute bacterial skin and skin-structure infections (ABSSSI), one of the major challenges to the health system worldwide. Although the use of antibiotics as the first line of intervention for MRSA-infected wounds is recommended, important side effects could occur, including cytotoxicity or immune dysregulation, thus affecting the repair process. Here, we show that the oxazolidinone antibiotic linezolid (LZD) impairs wound healing by aberrantly increasing interleukin 1 ß (IL-1ß) production in keratinocytes. Mechanistically, LZD triggers a reactive oxygen species (ROS)-independent mitochondrial damage that culminates in increased tethering between the endoplasmic reticulum (ER) and mitochondria, which in turn activates the NLR family pyrin domain-containing 3 (NLRP3) inflammasome complex by promoting its assembly to the mitochondrial surface. Downregulation of ER-mitochondria contact formation is sufficient to inhibit the LZD-driven NLRP3 inflammasome activation and IL-1ß production, restoring wound closure. These results identify the ER-mitochondria association as a key factor for NLRP3 activation and reveal a new mechanism in the regulation of the wound healing process that might be clinically relevant.

Tigecycline accelerates staphylococcal-infected burn wound healing through matrix metalloproteinase-9 modulation.

OBJECTIVES: We investigated the in vivo efficacy of tigecycline, a new glycylcycline (a tetracycline derivative), in the management of methicillin-resistant Staphylococcus aureus (MRSA)-infected experimental surgical wounds in rats. The main outcome measures were quantitative bacterial culture, histological examination and immunohistochemical expression of matrix metalloproteinase-9 (MMP-9) and collagen IV. METHODS: An animal model was used to compare the in vivo efficacy of teicoplanin and tigecycline in the treatment of burn wound infections by S. aureus. A copper bar, heated in boiling water, was placed on the paraspinal site of each rat, resulting in full thickness burns. A small gauze was placed over each burn and then inoculated with 5 × 10(7) cfu of S. aureus ATCC 43300. To mimic the clinical situation in burn patients, surgical debridement was performed 48 h after the injury. The wounds were left to heal by secondary intention. The study included an uninfected control group that did not receive any treatment, a contaminated group that did not receive any treatment, and two contaminated groups treated with intraperitoneal tigecycline (2 mg/kg) and teicoplanin (7 mg/kg), respectively. RESULTS: All antibiotic treatments were significantly effective. Tigecycline showed the highest antimicrobial activity, with a better impact on histological results. Infected rats treated with tigecycline showed a significant decrease in MMP-9 expression both in epithelium and in dermis compared with rats treated with teicoplanin. CONCLUSIONS: Tigecycline, besides its antimicrobial activity, exerts an important modulatory effect on MMP-9, accelerating wound healing in staphylococcal-infected burns.