The structures and functional activities of metalloproteinases from snake venoms have been widely studied because of the importance of these molecules in envenomation. Batroxase, which is a ...metalloproteinase isolated from Bothrops atrox (Pará) snake venom, was obtained by gel filtration and anion exchange chromatography. The enzyme is a single protein chain composed of 202 amino acid residues with a molecular mass of 22.9kDa, as determined by mass spectrometry analysis, showing an isoelectric point of 7.5. The primary sequence analysis indicates that the proteinase contains a zinc ligand motif (HELGHNLGISH) and a sequence C164I165M166 motif that is associated with a “Met-turn” structure. The protein lacks N-glycosylation sites and contains seven half cystine residues, six of which are conserved as pairs to form disulfide bridges. The three-dimensional structure of Batroxase was modeled based on the crystal structure of BmooMPα-I from Bothrops moojeni. The model revealed that the zinc binding site has a high structural similarity to the binding site of other metalloproteinases. Batroxase presented weak hemorrhagic activity, with a MHD of 10μg, and was able to hydrolyze extracellular matrix components, such as type IV collagen and fibronectin. The toxin cleaves both α and β-chains of the fibrinogen molecule, and it can be inhibited by EDTA, EGTA and β-mercaptoethanol. Batroxase was able to dissolve fibrin clots independently of plasminogen activation. These results demonstrate that Batroxase is a zinc-dependent hemorrhagic metalloproteinase with fibrin(ogen)olytic and thrombolytic activity.
► Batroxase is a weakly hemorrhagic metalloproteinase. ► Represent 1.2% (w/w) of the crude snake venom, pI 7.5 and molecular mass 22.9kDa. ► Batroxase presented thrombolytic and fibrin(ogen)olytic activity. ► Batroxase was characterized as a PIb class SVMP. ► Clinical use as fibrinolytic agent for the treatment of coagulation disorders.
Subclinical systemic inflammation is a hallmark of obesity and insulin resistance. The results obtained from a number of experimental studies suggest that targeting different components of the ...inflammatory machinery may result in the improvement of the metabolic phenotype. Unsaturated fatty acids exert antiinflammatory activity through several distinct mechanisms. Here, we tested the capacity of ω3 and ω9 fatty acids, directly from their food matrix, to exert antiinflammatory activity through the G protein-coupled receptor (GPR)120 and GPR40 pathways. GPR120 was activated in liver, skeletal muscle, and adipose tissues, reverting inflammation and insulin resistance in obese mice. Part of this action was also mediated by GPR40 on muscle, as a novel mechanism described. Pair-feeding and immunoneutralization experiments reinforced the pivotal role of GPR120 as a mediator in the response to the nutrients. The improvement in insulin sensitivity in the high-fat substituted diets was associated with a marked reduction in tissue inflammation, decreased macrophage infiltration, and increased IL-10 levels. Furthermore, improved glucose homeostasis was accompanied by the reduced expression of hepatic gluconeogenic enzymes and reduced body mass. Thus, our data indicate that GPR120 and GPR40 play a critical role as mediators of the beneficial effects of dietary unsaturated fatty acids in the context of obesity-induced insulin resistance.
The aim of this review was to examine current knowledge of the role of interleukin‐6 (IL‐6) in apical periodontitis (AP) pathogenesis as an inflammatory or pro‐inflammatory cytokine. It also looked ...at whether IL‐6 could serve as a measure for differential diagnosis or as a biomarker that can further predict the progression of bone resorption. A systematic review relating to AP and IL‐6 was made via PubMed, BIOSIS, Cochrane, EMBASE and Web of Science databases using keywords and controlled vocabulary. Two independent reviewers first screened titles and s and then the full texts. The reference lists of the identified publications were examined for additional titles. Eighteen papers were studied in total. In vitro studies (n = 6) revealed that IL‐6 is present in AP, and its levels are proportional to the size of the periapical lesions. Neutrophils and macrophages resident in these lesions can produce IL‐6 in vitro after a bacterial stimulus. Animal studies (n = 5) showed that IL‐6 is present in AP and that osteoblasts can produce IL‐6 in vivo. On the other hand, two studies using IL‐6 knockout mice revealed larger periapical lesions when compared with control groups, demonstrating IL‐6's role as an anti‐inflammatory cytokine. In human studies (n = 7), IL‐6 was identified in AP, and its levels were higher in symptomatic, epithelialized and large lesions than in asymptomatic and small lesions. These data lead to the conclusion that IL‐6 may play a pro‐inflammatory role, increasing its levels and reabsorbing bone in the presence of infections. When IL‐6 is not present, other cytokines such as IL‐1 and TNF‐α induce bone resorption. Further studies about the relationship between AP development and the cytokine network must be performed to establish the exact role of each cytokine in the inflammatory process.
Renewable fuels have been used for years as an option for supplying energy demand in a sustainable manner. In terms of liquid fuels, hydrotreated vegetable oil (HVO) gained special attention in the ...last few years due to its good performance in diesel engines, low emissions and renewable aspect. At the same time, bioethanol represents another renewable option for energy supply and has been consolidated in the market for decades. Even though these biofuels are assumed to be environmentally friendly, a complete understanding of their environmental impacts should take into account several indicators, applications and geographical aspects. In this sense, this study presents a detailed Life Cycle Assessment (LCA) regarding the use of petrodiesel, HVO from palm and soybean oil and bioethanol in various operating conditions in a diesel engine, for small-scale electricity generation in stationary applications. Diesel and HVO are used as pilot fuels, while bioethanol was injected in the intake port in various Energy Fraction Ratios (EF), EF = 0%; EF = 28%; EF = 32%; EF = 40%; EF = 44%, in the so-called dual-fuel mode. The results obtained with pure HVO showed reductions in specific levels of NOx, HC, CO and particulate matter (PM) emissions of 30%, 75%, 81% and 55.3%, respectively, and 4.36% efficiency when compared to diesel. The Dual-Fuel application provided a significant reduction in CO2, NOX and PM emissions, but decreased engine efficiency by up to 9.4%. The LCA showed that the palm oil HVO has an environmental performance superior to the soybean HVO and is capable of reducing the Global Warming Potential up to 75%. Palm oil HVO reduces impacts in categories such as Terrestrial Acidification, Ozone Formation and Consumption of non-renewable resources when compared to diesel. The environmental impact of the dual-fuel operation presents a decrease in the levels of Global Warming Potential, Depletion of Fossil Resources and Ozone Formation.
•HVO emissions analysis and LCA were made in single and dual-fuel mode in a CI engine.•HVO decreased emissions and improved thermal efficiency.•Port-injected ethanol decreased NOX, PM and CO2, but increased CO and HC.•HVO reduced GWP, but palm oil HVO emits less CO2 than soybean oil HVO.•Palm oil HVO presents better environmental performance than soybean oil HVO.
Lipoproteins are immunostimulatory bacterial components suggested to participate in inflammation-induced bone loss in periodontal disease through stimulation of osteoclast differentiation. Toll-like ...receptor 2 activation by Pam2CSK4 (PAM2), known to mimic bacterial lipoproteins, was previously shown to enhance periodontal bone resorption in mice. The anti-inflammatory cytokine interleukin-4 (IL-4) is a known inhibitor of RANKL-induced bone resorption in vitro. Here, we have investigated whether IL-4 could decrease PAM2-induced periodontal bone loss and osteoclastogenesis in vivo. In a model of periodontitis induced by gingival injections of PAM2 in mice, concomitant injections of IL-4 reduced bone loss. Histologically, IL-4 reduced the recruitment of inflammatory cells and the formation of TRAP+ osteoclasts stimulated by PAM2. Mouse bone marrow macrophages (BMMs) and neonatal calvarial osteoblasts were used to assess the effect of IL-4 on PAM2-induced osteoclastogenesis in vitro. In RANKL-primed BMMs stimulated by PAM2 Nfatc1, Ctsk, and Acp5 gene expression was up-regulated and resulted in robust formation of TRAP+ multinucleated osteoclasts, effects which were impaired by IL-4. These effects were mediated by impairment in PAM2-induced c-fos expression. In primary calvarial osteoblast cultures, IL-4 decreased PAM2-induced Tnfsf11 (encoding RANKL) mRNA and enhanced Tnfrsf11b (encoding OPG) expression. Our data demonstrate that the osteoprotective effect by IL-4 on lipoprotein-induced periodontal disease occurs through the inhibition of osteoclastogenesis by three mechanisms, one by acting directly on osteoclast progenitors, another by acting indirectly through decreasing the expression of osteoclast-regulating cytokines in osteoblasts and a third by decreasing inflammation.
Aim
To investigate the relationship between apical periodontitis and atherosclerosis in rats by lipid profile and carotid artery intima tunic measurement, and histological and histometric evaluation ...of periapical lesions.
Methodology
Forty male Wistar rats were allocated into four groups: control (C), with apical periodontitis (AP), with atherosclerosis (AT) and with AP and AT (AP + AT). Atherosclerosis was induced using a high‐lipid diet associated with a surgical ligature in the carotid artery and a super dosage of vitamin D3. AP was induced via pulp exposure to the oral environment. At 45 and 75 days, serum levels of total cholesterol (TC), triglycerides (TG), high‐density lipoprotein cholesterol (HDL‐C) and low‐density lipoprotein cholesterol (LDL‐C) were measured. The maxillary and mandibular jaws and carotid artery were collected and processed for histological analysis. The Kruskal–Wallis or Mann–Whitney test was performed for nonparametric data, and the Tukey’s or Student’s t‐test was performed for parametric data (P < 0.05).
Results
In nonatherosclerotic animals, the induction of apical periodontitis increased TG levels significantly, from 63.1 ± 11.4 mg dL−1 in group C to 88.2 ± 7.9 mg dL−1 in the AP group (P < 0.05). The induction of AP was associated with a trend for higher TC and LDL‐C levels in atherosclerotic animals (P > 0.05); however, it only significantly increased TG levels, from 93.2 ± 18.0 mg dL−1 in AT group to 121.9 ± 14.5 mg dL−1 in the AP + AT group (P < 0.05). Animals in the AP + AT group had a 36.5% increase in the thickness of the carotid intima tunic when compared with the AT group (P < 0.05). The intensity of the inflammatory infiltrate was significantly larger in the AP + AT group when compared with AP group (P < 0.05). The AP + AT group exhibited significantly greater alveolar bone loss, with a periapical lesion size of 206.4 ± 56.3 × 104 μm2, compared with 151.4 ± 49.1 × 104 μm2 in the AP group (P < 0.05).
Conclusion
Apical periodontitis influenced triglyceride levels, increasing them even in the absence of atherosclerosis, and influenced the increase in the thickness of the carotid artery intima tunic in the presence of atherosclerosis. Atherosclerosis intensified the inflammatory reaction and increased bone resorption in periapical lesions.
Aim
To investigate the effect of chronic alcohol consumption on apical periodontitis in rats.
Methodology
Thirty‐two male Wistar rats were arranged into four groups: Control (C): without apical ...periodontitis and nonalcoholic diet; (AL): without apical periodontitis and alcoholic diet; (AP): with apical periodontitis and nonalcoholic diet; and (AP + AL): with apical periodontitis and alcoholic diet. The alcoholic solution at 20% was given to the AL and AP + AL groups as the sole source of hydration throughout the experiment. AP was induced in the mandibular left first molars at the end of the 4th week. Weight changes and the amount of solid and liquid foods were recorded for 8 weeks. At the end, the animals were euthanized and the jaws removed followed by histological processing for histopathological and RANKL, OPG, TRAP and HIF‐1α analyses. The Mann–Whitney test was used for nonparametric data, and anova followed by the Tukey test was performed for parametric data, with P < 0.05.
Results
Animals that received the alcoholic diet had a lower weight gain than the other groups (P < 0.05). Control and AL groups did not have an inflammatory response in the periapical tissues. The median score of inflammatory infiltrate was significantly higher in the AP + AL group (2.5) compared to the AP group (1.5; P < 0.05). In the same comparison, AP + AL was associated with score 3 for RANKL and HIF‐1α versus score 2 for AP group (P < 0.05). Moreover, the values for TRAP were 3.88 ± 0.70 cells mm−1 for the AP + AL group and 2.43 ± 0.94 cells mm−1 for the AP group (P < 0.05).
Conclusion
In rats, an alcoholic diet had a significant effect on the severity of apical periodontitis, exacerbating the inflammatory response and osteoclastogenesis.
•A tripeptide from Bothrops atrox venom was isolated and characterized.•It protects against apoptosis induced by MPP+ in PC12 cells.•It has neurotrophic effect on non-NGF-stimulated PC12 cells.•It ...protects against the impairment of differentiation in MPP+-treated PC12 cells.•It might be useful in the treatment of Parkinson’s disease.
Parkinson’s disease (PD) is the second most common neurodegenerative disorder; however, there is no treatment able to prevent the loss of dopaminergic neurons or its consequences. Trophic factors such as NGF and BDNF has positive effects on different disorders of the brain, including neurodegeneration. Additionally, studies have suggested the use of venom peptides as a therapeutic strategy for neurological disorders. Therefore, in the present study, we investigated the neuroprotective activity of a peptide isolated from Bothrops atrox venom and its trophic ability by using a cellular model of dopaminergic neurotoxicity induced by 1-methyl-4-phenylpyridinium (MPP+) in PC12 cells. We showed that it decreased the activities of the apoptotic proteases caspase-9 (mitochondrial) and caspase-3 (executor) and increased cell viability and proliferation in this model. Additionally, it increased neuritogenesis in non-treated PC12 cells (neuronal model) as well as in PC12 cells treated with the dopaminergic neurotoxin. The amino acid sequence of the peptide was identified as Glutamic acid–Valine–Tryptophan (Glu–Val–Trp). These findings suggest that this tripeptide has the potential to protect against the dopaminergic neurons loss and that trophic stimulation of neuroplasticity might be involved in its mechanism of neuroprotection.
Background. Propolis is rich in polyphenols, especially flavonoids and phenolic acids, and has significant antioxidant activity, shown mainly in “in vitro” studies. Objective. The aim of this study ...was to evaluate the antioxidant efficacy and safety of a standardized propolis extract in healthy volunteers. Design. A two-phase sequential, open-label, nonrandomized, before and after clinical trial. Methods. Healthy participants received two EPP-AF® doses (375 and 750 mg/d, P.O, tid) during 7 ± 2 days, starting with the lower doses. Immediately before starting EPP-AF® administration and at the end of each 7-day dosing schedule, blood and urine samples were collected for quantification of 8-OHDG (8-hydroxydeoxyguanosine) and 8-ISO (8-isoprostanes) in urine and GSH (reduced glutathione), GSSG (oxidized glutathione), SOD (superoxide dismutase), FRAP (Ferric Reducing Antioxidant Power), vitamin E, and MDA (malondialdehyde) in plasma. Results. In our study, we had 34 healthy participants (67.7% women, 30 ± 8 years old, 97% white). The 8-ISO, a biomarker of lipid peroxidation, decreased with both doses of EPP-AF® compared to baseline (8-ISO, 1.1 (0.9–1.3) versus 0.85 (0.75–0.95) and 0.89 (0.74–1.0), ng/mg creatinine, P<0.05, for 375 and 750 mg/d EPP-AF® doses versus baseline, mean and CI 95%, respectively). 8-OHDG, a biomarker of DNA oxidation, was also reduced compared to baseline with 750 mg/d doses (8-OHDG, 15.7 (13.2–18.1) versus 11.6 (10.2–13.0), baseline versus 750 mg/d, respectively, ng/mg creatinine, P<0.05). Reduction of biomarkers of oxidative stress damage was accompanied by increased plasma SOD activity (68.8 (66.1–73.3) versus 78.2 (72.2–80.5) and 77.7 (74.1–82.6), %inhibition, P<0.0001, 375 and 750 mg/d versus baseline, median and interquartile range 25–75%, respectively) and by increased GSH for 375 mg/d EPP-AF® doses (1.23 (1.06–1.34) versus 1.33 (1.06–1.47), μmol/L, P<0.05). Conclusion. EPP-AF® reduced biomarkers of oxidative stress cell damage in healthy humans, with increased antioxidant enzymatic capacity, especially of SOD. This trial is registered with the Brazilian Registry of Clinical Trials (ReBEC, RBR-9zmfs9).
Abstract
Molluscs play a crucial role as ecosystem engineer by providing habitat for other organisms. However, little is known about the shells’ ability to host other species, especially in tropical ...ecosystems like Pari Island. In sandy locations, hard substrates are scarce, but clam shells introduce substrate heterogeneity. Our study focused on the Venus Clam
(Gafrarium tumidum)
, prevalent in the seagrass bed ecosystem on Pari Island, to explore the epibiont species residing on its shells. Epibionts were examined through visual observation and microscopy analysis in a laboratory. We found the attached epibionts were categorized into three main groups. The first group was macroalgae, specifically
Padina
sp., which attached to the posterior part of the clam shell, relying on stable substrates to withstand waves. The second group encompassed microalgae, including
Bacillaria, Nitzchia, Prorocentrum, Pseudo-nitzschia, Surirella
, and
Trichodesmium
. These microalgae have diverse ecological roles, including causing harmful algal blooms and nitrogen fixation. The third group consisted of possibly cyanobacteria forming blue-green biofilms on clam shells, predominantly on recently deceased or living clams, mainly in exposed, sunlit areas. This research emphasizes the significant role of clam shells in supporting epibiont species richness in the ecosystem.
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