COPD Patients Exhibit Distinct Gene Expression, Accelerated Cellular Aging, and Bias to M2 Macrophages.

COPD, one of world's leading contributors to morbidity and mortality, is characterized by airflow limitation and heterogeneous clinical features. Three main phenotypes are proposed: overlapping asthma/COPD (ACO), exacerbator, and emphysema. Disease severity can be classified as mild, moderate, severe, and very severe. The molecular basis of inflammatory amplification, cellular aging, and immune response are critical to COPD pathogenesis. Our aim was to investigate EP300 (histone acetylase, HAT), HDAC 2 (histone deacetylase), HDAC3, and HDAC4 gene expression, telomere length, and differentiation ability to M1/M2 macrophages. For this investigation, 105 COPD patients, 42 smokers, and 73 non-smoker controls were evaluated. We identified a reduced HDAC2 expression in patients with mild, moderate, and severe severity; a reduced HDAC3 expression in patients with moderate and severe severity; an increased HDAC4 expression in patients with mild severity; and a reduced EP300 expression in patients with severe severity. Additionally, HDAC2 expression was reduced in patients with emphysema and exacerbator, along with a reduced HDAC3 expression in patients with emphysema. Surprisingly, smokers and all COPD patients showed telomere shortening. COPD patients showed a higher tendency toward M2 markers. Our data implicate genetic changes in COPD phenotypes and severity, in addition to M2 prevalence, that might influence future treatments and personalized therapies.

Elastase modifies bleomycin-induced pulmonary fibrosis in mice.

Pulmonary fibrosis (PF) is characterized by excessive accumulation of collagen in the lungs. Emphysema is characterized by loss of the extracellular matrix (ECM) and alveolar enlargement. We studied the co-participation of elastase-induced mild emphysema in bleomycin-induced PF in mice by analyzing oxidative stress, inflammation and lung histology. C57BL/6 mice were divided into four groups: control; bleomycin (0.1U/mouse); elastase (using porcine pancreatic elastase (PPE)+bleomycin (3U/mouse 14 days before 0.1U/mouse of bleomycin; PPE+B); elastase (3U/mouse). Mice were humanely sacrificed 7, 14 and 21 days after treatment with bleomycin or vehicle. PF was observed 14 days and 21 days after bleomycin treatment but was observed after 14 days only in the PPE+B group. In the PPE+B group at 21 days, we observed many alveoli and alveolar septa with few PF areas. We also observed marked and progressive increases of collagens 7, 14 and 21 days after bleomycin treatment whereas, in the PPE+B group, collagen deposition was observed only at 14 days. There was a reduction in activities of the antioxidant enzymes superoxide dismutase (p<0.05), catalase (p<0.01) and glutathione peroxidase (p<0.01) parallel with an increase in nitrite (p<0.01) 21 days after bleomycin treatment compared with the control group. These endpoints were also reduced (p<0.05, p<0.05 and p<0.01, respectively) and increased (p<0.01) in the PPE+B group at 21 days compared with the control group. Interleukin (IL)-1ß expression was upregulated (p<0.01) whereas IL-6 was downregulated (p<0.05) in the PPE+B group at 21 days compared with the control group. PF and emphysema did not coexist in our model of lung disease and despite increased levels of oxidative stress and inflammatory markers after combined stimulus (elastase and bleomycin) overall histology was improved to that of the nearest control group.

Supplementation with vitamins C and E improves mouse lung repair.

Cigarette smoke (CS) induces emphysema by tissue destruction through the production of oxidants and metalloproteinases [matrix metalloproteinases (MMPs)]. The possibility of lung repair after emphysema remains unclear. Our aim was to study the effects of vitamins C and E on mouse lung repair evaluated by catalase (CAT), superoxide dismutase (SOD) and MMP-9 activities; by the amount of tumor necrosis factor (TNF)-alpha in lung homogenates; by cell quantification in bronchoalveolar lavage (BAL) fluid; and by lung histology. Male C57BL/6 mice (n=25) were exposed to nine cigarettes per day, 7 days/week, for 60 days in a whole-body exposure chamber. The control group was sham smoked (n=10). After 60 days of CS exposure, a group of animals was sacrificed (n=5) and the others were divided into two groups: (a) CSv (n=10) supplemented with saline and olive oil (vehicles) for 60 days and (b) CSr (n=10) supplemented with vitamins C and E (50 mg/kg/day) for 60 days. These mice were then sacrificed; BAL was performed and the lungs were removed for biochemical and histological analysis. The results demonstrated that CAT activity was decreased in the CSv and CSr groups compared to the control group. SOD activity was higher in the CSv group than in the control and CSr groups. The CSv group showed a higher neutrophil count in BAL fluid, associated with more TNF-alpha in lung homogenates, than the control or CSr groups. Finally, emphysema in the CSv group was associated with fewer collagen and elastic fibers than in the control and CSr groups. These results indicate a possible role of vitamins C and E in lung repair after emphysema induced by long-term CS exposure in mice.

Implants of an adhesive resin, a calcium hydroxide, and a glass-ionomer cement cause reactional fibrosis with mast cells involvement in rats.

OBJECTIVES: To evaluate the tissue reaction of some pulpar protecting materials. METHOD AND MATERIALS: Standardized implants of calcium hydroxide (CH), glass-ionomer cement (GIC), and light-cured dentin adhesive (LDA), surgically introduced into the dorsal connective tissue of Wistar rats, were left for 15 and 30 days. For each of the 2 experimental times, a respective sham group (S) was studied. After experimentation, animals were sacrificed, and the material from implant sites was removed and studied with light microscopy and stereology (volume density of interstitial fibrosis, Vv[f], and numerical density of mast cells per area, NA[mast cell]). The implants and the surfaces of the fibrous capsule were analyzed with scanning electronic microscopy (SEM) adapted with microanalysis. RESULTS: The CH group had the smallest value of Vv[f] and the LDA group the greatest. At day 30, the Vv[f] of the LDA group showed an increase of 30% and was different from that of the CH group in the same period (P <.05). The NA[mast cell] was smaller in both the CH and the S group than in the LDA group (P <.05). The GIC group had intermediate values for Vv[f] and NA[mast cell] between CH and LDA values. There was light fibrosis in the surgical area with few mast cells associated to vessels in the S group. SEM detected presence of silica fragments in the fibrous capsule of the LDA group and calcium in the fibrous capsule of the CH group. CONCLUSIONS: All tested materials allowed healing of the implanted area; tissue reaction was smallest in the CH group.

Mast cells in tissue response to dentistry materials: an adhesive resin, a calcium hydroxide and a glass ionomer cement.

Synthetic materials used in dentistry may trigger various inflammatory responses. In order to evaluate biocompatibility, standardized implants of Calcium Hydroxide (CH), Glass Ionomer Cement (GIC) and Light-activated Dental Adhesive (LDA) were surgically introduced into Wistar rats' back bone. Six (experimental) animal groups, five each, and two Sham (S) groups were studied after 15 and 30 days from surgery. In each animal, the density of mast cells and interstitial fibrosis volume was evaluated by quantitative light microscopy. In addition, the interaction between the disk material and its fibrous capsule was evaluated by scanning electron microscopy. The density of mast cells per area (N(A)[mast cells]) was lower in CH group than in LDA group. GIC group displayed N(A)[mast cells] results intermediate between CH and LDA groups (p<0.05). The smallest interstitial fibrosis volume density (Vv[f]) was observed in CH group, then in GIC group, while the greatest in LDA group. After 30 days, the fibrosis in LDA group was 30% higher than in CH group (p<0.05). In S group, discreet fibrosis restricted to surgical area was present, with few mast cells near the vessels. Significant interaction between fibrous capsule and the surrounding disk material was most evident in CH group. The implanted materials induced mast cell migration, distinct fibrosis development, suggesting that CH is the most biocompatible material among those tested.

Cutaneous wound healing: myofibroblastic differentiation and in vitro models.

Wound healing is an interactive, dynamic 3-phased process. During the formation of granulation tissue, many fibroblastic cells acquire some morphological and biochemical smooth muscle features and are called myofibroblasts. Myofibroblasts participate in both granulation tissue formation and remodeling phases. Excessive scarring, which is a feature of impaired healing, is a serious health problem that may affect the patient's quality of life. The treatment costs of such lesions are high, and often, the results are unsatisfactory. To understand the wound healing process better and to promote improvement in human healing, models are needed that can predict the in vivo situation in humans. In vitro models allow the study of cell behavior in a controlled environment. Such modeling partitions and reduces to small scales behavior perceived in vivo. This article is focused on "fibroblasts". In vitro models to study wound healing, the role of (myo)fibroblasts, and skin reconstruction in tissue replacement and promotion of wound healing are discussed.