Exploring the protein profile and biological activity of Crotalus molossus venom against E. coli, P. aeruginosa and S. aureus bacteria and T47D breast carcinoma cells.

Mexico has the highest diversity of snake species in the world, following Australia when considering just venomous snakes. Specifically, in Sonora, the second largest state in the country, more than 15 highly venomous species occur, including the northern black-tailed rattlesnake (Crotalus molossus). This specie's venom has not been as thoroughly researched in contrast with other Mexican vipers, nevertheless some studies report its biological activity and even pharmacological potential with antibacterial and cytotoxic activity. In this study we identified the main protein components from a pool of C. molossus venom through a gel-free proteomics approach, reporting ∼140 proteins belonging to the SVMP (38.76%), PLA2 (28.75%), CTL (11.93%), SVSP (6.03%) and LAAO (5.67%) toxin families. To study its biological activities, we evaluated its hemolytic, antibacterial, and cytotoxic activity in red blood cells, Gram positive and negative bacteria and a luminal A breast carcinoma cell line (T47D), respectively, in vitro. We report that concentrations <100 µg/mL are potentially not hemolytic and reduced the bacteria viability of E. coli and S. aureus with an IC50 of 10.27 and 11.51 µg/mL, respectively. Finally, we determined the C. molossus venom as cytotoxic against the T47D breast carcinoma cell line, with an IC50 of 1.55 µg/mL. We suggest that the evaluated cytotoxicity was due to a high abundance of SVMPs and PLA2s, since it's been reported that they affect the extracellular matrix and membrane permeation. This may provide a useful tool for pharmaceutical screening in the future.

Role of the complement system in kidney cell death induced by Loxosceles venom Sphingomyelinases D.

Envenomation by Loxosceles spiders can result in local and systemic pathologies. Systemic loxoscelism, which can lead to death, is characterized by intravascular hemolysis, platelet aggregation, and acute kidney injury. Sphingomyelinase D (SMase D) in Loxosceles spider venom is responsible for both local and systemic pathologies, and has been shown to induce metalloprotease activity. As the complement system is involved in many renal pathologies and is involved in hemolysis in systemic loxoscelism, the aim of this study was to investigate its role and the role of complement regulators and metalloproteases in an in vitro model of Loxosceles venom induced renal pathology. We investigated the effects of the venom/SMase D and the complement system on the HK-2 kidney cell line. Using cell viability assays, western blotting, and flow cytometry, we show that human serum, as a source of complement, enhanced the venom/SMase D induced cell death and the deposition of complement components and properdin. Inhibitors for ADAM-10 and ADAM-17 prevented the venom induced release of the of the complement regulator MCP/CD46 and reduced the venom/SMase D induced cell death. Our results show that the complement system can contribute to Loxosceles venom induced renal pathology. We therefore suggest that patients experiencing systemic loxoscelism may benefit from treatment with metalloproteinase inhibitors and complement inhibitors, but this proposition should be further analyzed in future pre-clinical and clinical assays.

Identification, Biochemical Characterization, and In Vivo Detection of a Zn-Metalloprotease with Collagenase Activity from Mannheimia haemolytica A2.

Respiratory diseases in ruminants are a main cause of economic losses to farmers worldwide. Approximately 25% of ruminants experience at least one episode of respiratory disease during the first year of life. Mannheimia haemolytica is the main etiological bacterial agent in the ruminant respiratory disease complex. M. haemolytica can secrete several virulence factors, such as leukotoxin, lipopolysaccharide, and proteases, that can be targeted to treat infections. At present, little information has been reported on the secretion of M. haemolytica A2 proteases and their host protein targets. Here, we obtained evidence that M. haemolytica A2 proteases promote the degradation of hemoglobin, holo-lactoferrin, albumin, and fibrinogen. Additionally, we performed biochemical characterization for a specific 110 kDa Zn-dependent metalloprotease (110-Mh metalloprotease). This metalloprotease was purified through ion exchange chromatography and characterized using denaturing and chaotropic agents and through zymography assays. Furthermore, mass spectrometry identification and 3D modeling were performed. Then, antibodies against the 110 kDa-Mh metalloprotease were produced, which achieved great inhibition of proteolytic activity. Finally, the antibodies were used to perform immunohistochemical tests on postmortem lung samples from sheep with suggestive histology data of pneumonic mannheimiosis. Taken together, our results strongly suggest that the 110-Mh metalloprotease participates as a virulence mechanism that promotes damage to host tissues.

Role of the complement system in kidney cell death induced by Loxosceles venom Sphingomyelinases D

Envenomation by Loxosceles spiders can result in local and systemic pathologies. Systemic loxoscelism, which can lead to death, is characterized by intravascular hemolysis, platelet aggregation, and acute kidney injury. Sphingomyelinase D (SMase D) in Loxosceles spider venom is responsible for both local and systemic pathologies, and has been shown to induce metalloprotease activity. As the complement system is involved in many renal pathologies and is involved in hemolysis in systemic loxoscelism, the aim of this study was to investigate its role and the role of complement regulators and metalloproteases in an in vitro model of Loxosceles venom induced renal pathology. We investigated the effects of the venom/SMase D and the complement system on the HK-2 kidney cell line. Using cell viability assays, western blotting, and flow cytometry, we show that human serum, as a source of complement, enhanced the venom/SMase D induced cell death and the deposition of complement components and properdin. Inhibitors for ADAM-10 and ADAM-17 prevented the venom induced release of the of the complement regulator MCP/CD46 and reduced the venom/SMase D induced cell death. Our results show that the complement system can contribute to Loxosceles venom induced renal pathology. We therefore suggest that patients experiencing systemic loxoscelism may benefit from treatment with metalloproteinase inhibitors and complement inhibitors, but this proposition should be further analyzed in future pre-clinical and clinical assays.

Age-dependent changes on fractalkine forms and their contribution to neurodegenerative diseases.

The chemokine fractalkine (FKN, CX3CL1), a member of the CX3C subfamily, contributes to neuron-glia interaction and the regulation of microglial cell activation. Fractalkine is expressed by neurons as a membrane-bound protein (mCX3CL1) that can be cleaved by extracellular proteases generating several sCX3CL1 forms. sCX3CL1, containing the chemokine domain, and mCX3CL1 have high affinity by their unique receptor (CX3CR1) which, physiologically, is only found in microglia, a resident immune cell of the CNS. The activation of CX3CR1contributes to survival and maturation of the neural network during development, glutamatergic synaptic transmission, synaptic plasticity, cognition, neuropathic pain, and inflammatory regulation in the adult brain. Indeed, the various CX3CL1 forms appear in some cases to serve an anti-inflammatory role of microglia, whereas in others, they have a pro-inflammatory role, aggravating neurological disorders. In the last decade, evidence points to the fact that sCX3CL1 and mCX3CL1 exhibit selective and differential effects on their targets. Thus, the balance in their level and activity will impact on neuron-microglia interaction. This review is focused on the description of factors determining the emergence of distinct fractalkine forms, their age-dependent changes, and how they contribute to neuroinflammation and neurodegenerative diseases. Changes in the balance among various fractalkine forms may be one of the mechanisms on which converge aging, chronic CNS inflammation, and neurodegeneration.

Anti-Metalloproteases: Production and Characterization of Polyclonal IgG Anti-F2 Fraction Antibodies Purified from the Venom of the Snake Bitis arietans.

Bitis arietans is a medically important snake found in Sub-Saharan Africa. The envenomation is characterized by local and systemic effects, and the lack of antivenoms aggravates the treatment. This study aimed to identify venom toxins and develop antitoxins. The F2 fraction obtained from Bitis arietans venom (BaV) demonstrated the presence of several proteins in its composition, including metalloproteases. Titration assays carried out together with the immunization of mice demonstrated the development of anti-F2 fraction antibodies by the animals. The determination of the affinity of antibodies against different Bitis venoms was evaluated, revealing that only BaV had peptides recognized by anti-F2 fraction antibodies. In vivo analyses demonstrated the hemorrhagic capacity of the venom and the effectiveness of the antibodies in inhibiting up to 80% of the hemorrhage and 0% of the lethality caused by BaV. Together, the data indicate: (1) the prevalence of proteins that influence hemostasis and envenomation; (2) the effectiveness of antibodies in inhibiting specific activities of BaV; and (3) isolation and characterization of toxins can become crucial steps in the development of new alternative treatments. Thus, the results obtained help in understanding the envenoming mechanism and may be useful for the study of new complementary therapies.

Interleukin-17 and Tumor Necrosis Factor Show a Functional Hierarchy to Regulate the Production of Matrix Metalloproteases by Monocytes from Patients with Psoriasis.

Interleukin-17 (IL-17) and tumor necrosis factor (TNF) regulate tissue remodeling through matrix metalloproteinases (MMPs). It is not yet clear whether these cytokines have a functional hierarchy in psoriasis. Serum levels of TNF (1,403 versus 1,058 pg/mL), IL-17 (1,528 versus 820 pg/mL), MMP-1 (1,999 versus 1,039 pg/mL), and MMP-9 (1,950 versus 1,561 pg/mL) were higher in psoriasis subjects (n = 60) than in control subjects (n = 60). Tissue inhibitor of MMPs (TIMP-1; 1,374 versus 1,218 pg/mL) was lower in psoriasis subjects. Serum IL-17 was correlated with MMP-2 (rs = 0.40) and TIMP-1 (rs = -0.26) levels. Unstimulated production of MMP-1, MMP-2, and MMP-9 by monocytes was higher in psoriasis subjects, whereas TIMP-1 production was lower. TNF stimulation increased all MMPs, whereas TIMP-1 production was unchanged. IL-17 stimulation increased all MMPs, whereas TIMP-1 production was decreased in psoriasis subjects. MMP-9 production was higher in monocytes stimulated with IL-17 compared with TNF. TIMP-1 production was decreased more by IL-17 than by TNF, but only in psoriasis cells. MMP-1/TIMP-1, MMP-2/TIMP-1, and MMP-9/TIMP-1 ratios were higher after IL-17 stimulation (compared with TNF stimulation) in psoriasis subjects; this occurred in controls only for the MMP-2/TIMP-1 ratio. IL-17 has a greater ability than TNF to dysregulate the MMPs/TIMP-1 balance, supporting IL-17 blockade as first-line treatment in cutaneous psoriasis.

Oxidative and Fibrinolytic Mechanisms: Two Important Processes to Consider in Platelet Storage

Objective: Platelet-rich plasma (PRP) is used in multiple coagulation disorders. Its therapeutic effectiveness relies on technical procedures related to PRP procurement and preservation because free radicals induce platelet activation and aging. This work aims to elucidate the oxidative mechanisms involved in activation of platelets obtained from PRP during storage. Materials and Methods: One hundred ten PRP batches were obtained from healthy donors and kept under stirring at a temperature of 20-24 °C. Protein extraction was performed from platelet homogenates and plasma at different times of storage from day 1 to 20. The activities of antioxidant markers such as catalase (CAT), superoxide dismutase, and ceruloplasmin, as well as fibrinolytic protein activity metalloproteases 2 and 3, plasmin, and urokinase plasminogen activator, were analyzed by zymography assays. Oxidized proteins were also determined. Results: Significant activity of antioxidant enzymes and fibrinolytic molecules was observed on day 5 of storage in PRP homogenates, which increased over time and was concomitantly correlated with oxidized protein levels. Reverse enzymatic activity patterns were observed in plasma, except for CAT, which remained unchanged. Conclusion: Storage conditions of platelets from PRP for up to 5 days induced in vitro platelet activation by oxidative damage and proteolysis. This finding confirms the need for proper management of these blood products to preserve their viability and functionality.

Anti-Metalloproteases: production and characterization of polyclonal IgG anti-F2 fraction antibodies purified from the venom of the snake bitis arietans

Bitis arietans is a medically important snake found in Sub-Saharan Africa. The envenomation is characterized by local and systemic effects, and the lack of antivenoms aggravates the treatment. This study aimed to identify venom toxins and develop antitoxins. The F2 fraction obtained from Bitis arietans venom (BaV) demonstrated the presence of several proteins in its composition, including metalloproteases. Titration assays carried out together with the immunization of mice demonstrated the development of anti-F2 fraction antibodies by the animals. The determination of the affinity of antibodies against different Bitis venoms was evaluated, revealing that only BaV had peptides recognized by anti-F2 fraction antibodies. In vivo analyses demonstrated the hemorrhagic capacity of the venom and the effectiveness of the antibodies in inhibiting up to 80% of the hemorrhage and 0% of the lethality caused by BaV. Together, the data indicate: (1) the prevalence of proteins that influence hemostasis and envenomation; (2) the effectiveness of antibodies in inhibiting specific activities of BaV; and (3) isolation and characterization of toxins can become crucial steps in the development of new alternative treatments. Thus, the results obtained help in understanding the envenoming mechanism and may be useful for the study of new complementary therapies.

Elevated Levels of Soluble CD147 are Associated with Hyperinflammation and Disease Severity in COVID-19: A Proof-of-Concept Clinical Study.

To evaluate soluble CD147 levels in COVID-19 and identify whether these are associated with hyperinflammation and disease severity. One-hundred and nine COVID-19 patients and 72 healthy blood donors were studied. Levels of CD147, matrix metalloproteases (MMP) and inflammatory markers were measured on hospital arrival, while the need for mechanical ventilation and the occurrence of death during hospitalization were recorded. CD147 levels were higher in COVID-19 (1.6, 1.0-2.3 vs 1.3, 1.0-1.6 ng/ml; P = 0.003) than controls. MMP-2 (9.2, 4.5-12.9 vs 4.2, 3.7-4.6 ng/ml; P < 0.001), MMP-3 (1.1, 0.9-1.3 vs 0.9, 0.7-1.0 ng/ml; P < 0.001) and MMP-9 (0.9, 0.5-1.2 vs 0.4, 0.2-0.6 ng/ml; P < 0.001) were also higher in COVID-19, while MMP-1 (0.6, 0-1.4 vs 0.6, 0.3-0.7 ng/ml; P = 0.711) was not different. Significant correlations were found between CD147 and MMP-2 (ρ = 0.34), MMP-3 (ρ = 0.21), interleukin 6 (ρ = 0.21), and the neutrophil/lymphocyte ratio (ρ = 0.26). Furthermore, CD147 levels were higher in patients who required mechanical ventilation (1.8, 1.4-2.4 vs 1.2, 0.8-1.9 ng/ml; P < 0.001) and in those who ultimately died (1.9, 1.4-2.7 vs 1.4, 0.9-1.9 ng/ml; P = 0.009). CD147 is elevated in COVID-19 and appears to contribute to hyperinflammation and disease severity.

Anti-metaloproteases: produção e caracterização de anticorpos policlonais IgG anti-metaloproteases purificadas do veneno da serpente Bitis arietans

Bitis arietans is a medical importance snake found predominantly in sub-Saharan Africa. The envenomation is characterized by local and systemic reactions, which can lead the victims to death or permanent disabilities. However, the lack of antivenoms makes the treatment worse. Therefore, the present work aimed to identify venom toxins, learn about their properties and develop antitoxins. The F2 fraction obtained from affinity chromatography fractionation of B. arietans venom showed the major proteolytic activity of SVMPs from enzymatic tests. Based on mass spectrometry analysis, 57 different peptides were identified in the F2 fraction. Among the most prevalent peptides are SVMPs. ELISA titration assays performed together with the mouse immunization step (BALB/c) demonstrated the development of anti-F2 fraction antibodies by the animals. The determination of the affinity of antibodies against different Bitis venoms was evaluated, revealing that only the B. arietans venom has peptides recognized by anti-F2 fraction antibodies. In vivo analyzes demonstrated the hemorrhagic capacity of the venom, the effectiveness of the antibodies to inhibit up to 80% of hemorrhage and 0% of the lethality caused by the venom. Taken together, the data indicate: 1) the prevalence of peptides that influence hemostasis and the dissemination of local and systemic effects caused by poisoning; 2) the effectiveness of monospecific antibodies in inhibiting specific activities of the venom; and 3) the isolation of toxins, production and characterization of antibodies is a crucial step in the development of new antivenoms. Therefore, the obtained results help in understanding the mechanism involved in the envenomation and can be useful for the study of new complementary therapies to antivenom in the treatment of accidents by Bitis arietans.

Bitis arietans é uma serpente de importância médica encontrada predominantemente na África Subsaariana. O envenenamento é caracterizado por efeitos locais e sistêmicos, que podem levar a morte ou incapacidades permanentes. No entanto, a carência de antivenenos agravam o tratamento. Portanto, este trabalho teve como objetivo identificar toxinas do veneno, conhecer suas propriedades e desenvolver antitoxinas. A fração F2 obtida do fracionamento por cromatografia de afinidade do veneno de B. arietans, demonstrou a atividade proteolítica majoritária de SVMPs a partir de testes enzimáticos. Com base na análise por espectrometria de massas, foram identificados 57 peptídeos diferentes na fração F2. Entre os peptídeos de maior prevalência estão as SVMPs. Ensaios de titulação por ELISA realizados em conjunto à etapa de imunização de camundongos (BALB/c), demonstraram o desenvolvimento de anticorpos anti-fração F2 pelos animais. A determinação da afinidade dos anticorpos contra diferentes venenos de Bitis foi avaliada, revelando que somente o veneno de B. arietans possui peptídeos reconhecidos pelos anticorpos anti-fração F2. Análises in vivo demonstraram a capacidade hemorrágica do veneno, a eficácia dos anticorpos de inibir em até 80% a hemorragia e em 0% da letalidade causadas pelo veneno. Em conjunto, os dados indicam: 1) a prevalência de peptídeos que atuam influenciando na hemostasia e na disseminação de efeitos locais e sistêmicos causados pelo envenenamento; 2) a eficácia de anticorpos monoespecíficos em inibir atividades específicas do veneno; e 3) o isolamento de toxinas, produção e caracterização de anticorpos é uma etapa crucial no desenvolvimento de novos antivenenos. Desta forma, os resultados obtidos auxiliam na compreensão no mecanismo de envenenamento e podem ser úteis para o estudo de novas terapias complementares ao antiveneno no tratamento dos acidentes por Bitis arietans.

Modulation of Adhesion Molecules Expression by Different Metalloproteases Isolated from Bothrops Snakes.

Snake venom metalloproteinases (SVMP) are involved in local inflammatory reactions observed after snakebites. Based on domain composition, they are classified as PI (pro-domain + proteolytic domain), PII (PI + disintegrin-like domains), or PIII (PII + cysteine-rich domains). Here, we studied the role of different SVMPs domains in inducing the expression of adhesion molecules at the microcirculation of the cremaster muscle of mice. We used Jararhagin (Jar)-a PIII SVMP with intense hemorrhagic activity, and Jar-C-a Jar devoid of the catalytic domain, with no hemorrhagic activity, both isolated from B. jararaca venom and BnP-1-a weakly hemorrhagic P1 SVMP from B. neuwiedi venom. Toxins (0.5 µg) or PBS (100 µL) were injected into the scrotum of mice, and 2, 4, or 24 h later, the protein and gene expression of CD54 and CD31 in the endothelium, and integrins (CD11a and CD11b), expressed in leukocytes were evaluated. Toxins induced significant increases in CD54, CD11a, and CD11b at the initial time and a time-related increase in CD31 expression. In conclusion, our results suggest that, despite differences in hemorrhagic activities and domain composition of the SVMPs used in this study, they behave similarly to the induction of expression of adhesion molecules that promote leukocyte recruitment.

Involvement of matrix metalloproteinases and their inhibitors in Staphylococcus aureus chronically infected bovine mammary glands during active involution.

The aim of this study was to characterize the protein expression of matrix metalloproteinase-2 (MMP-2) and -- 9 and their inhibitors (TIMP-1 and -2) in mammary tissue of dairy cows with naturally occurring chronic S. aureus intramammary infections (IMI) during active involution. Moreover, the gelatinolytic activity of MMP-2 and -9 in mammary secretions was evaluated. Cows in late lactation that were either uninfected or with chronic naturally acquired S. aureus IMI were included in this study. Protein expression of MMP-2 and -9 in mammary tissues was significantly higher in S. aureus-infected than uninfected quarters at day 14 and 21 of involution. Protein expression of TIMP-1 and -2 was significantly higher in S. aureus-infected than uninfected quarters at day 7, 14 and 21 of involution. The MMP-2/TIMP-1, MMP-2/TIMP-2, MMP-9/TIMP-1 and MMP-9/TIMP-2 ratios were significantly higher in S. aureus-infected compared with uninfected quarters at day 14 of involution. The MMP-2 activity was significantly higher in mammary secretions from S. aureus-infected compared with uninfected quarters at day 1, 2, 7 and 14 of involution. The MMP-9 activity was significantly higher in mammary secretions from infected quarters compared with uninfected quarters at day 7, 14 and 21 of involution. The increased expression of MMP-2 and -9 in mammary tissue as well as the high levels of activity observed in mammary secretion from infected quarters compared with uninfected quarters during active involution, strongly suggests that these gelatinases could contribute to degradation of mammary tissue components during chronic S. aureus IMI. The MMPs/TIMPs imbalance could lead to greater proteolysis and potentially more damage to mammary tissue in S. aureus-infected quarters.

Expression of matrix metalloproteinases and their inhibitors at the implantation site in ampullary ectopic pregnancies.

OBJECTIVE: This study investigated the qualitative and semi-quantitative expression of metalloproteinases (MMP) and their tissue inhibitors (TIMP) in trophoblastic tissue during ampullary ectopic pregnancies and correlated that expression with the degree of tubal invasion. STUDY DESIGN: It is a prospective study that included 34 patients diagnosed with ampullary tubal pregnancy who underwent salpingectomy. A histological evaluation of the depth of trophoblastic invasion in the tubes obtained was performed. Subsequently, the expression of the MMP-2, MMP-9, MMP-14, TIMP-1, TIMP-2 and TIMP-3 markers was qualitatively and semi-quantitatively evaluated by indirect immunohistochemistry. In addition, the degree of trophoblastic invasion was correlated with the expression of each marker and with the metalloproteinase/inhibitor ratios. RESULTS: MMP-2 (11.2 %; 3.6-17.9) was the marker with greater expression at the implantation site, both in the qualitative and semi-quantitative assessment, while MMP-9 (2.23 %; 0.2-5.4) and TIMP-3 (2.53 %; 0.1-15.3) were only weakly expressed. CONCLUSION: There was wide variation in expression among the markers and metalloproteinase/inhibitor ratios studied compared to the degrees of invasion.

Modulation of adhesion molecules expression by different metalloproteases isolated from Bothrops snakes

Snake venom metalloproteinases (SVMP) are involved in local inflammatory reactions observed after snakebites. Based on domain composition, they are classified as PI (pro-domain + proteolytic domain), PII (PI + disintegrin-like domains), or PIII (PII + cysteine-rich domains). Here, we studied the role of different SVMPs domains in inducing the expression of adhesion molecules at the microcirculation of the cremaster muscle of mice. We used Jararhagin (Jar)—a PIII SVMP with intense hemorrhagic activity, and Jar-C—a Jar devoid of the catalytic domain, with no hemorrhagic activity, both isolated from B. jararaca venom and BnP-1—a weakly hemorrhagic P1 SVMP from B. neuwiedi venom. Toxins (0.5 µg) or PBS (100 µL) were injected into the scrotum of mice, and 2, 4, or 24 h later, the protein and gene expression of CD54 and CD31 in the endothelium, and integrins (CD11a and CD11b), expressed in leukocytes were evaluated. Toxins induced significant increases in CD54, CD11a, and CD11b at the initial time and a time-related increase in CD31 expression. In conclusion, our results suggest that, despite differences in hemorrhagic activities and domain composition of the SVMPs used in this study, they behave similarly to the induction of expression of adhesion molecules that promote leukocyte recruitment.

From birth to adulthood: an analysis of the Brazilian lancehead (Bothrops moojeni) venom at different life stages

The Brazilian lancehead (Bothrops moojeni) has a wide distribution in Brazil and represents a serious public health hazard. Previous works reported that the symptoms of snakebites caused by B. moojeni juveniles’ bites were mainly related to coagulation, while those caused by adults’ bites had a more prominent local damage. In this work, we analyzed the venoms of B. moojeni at different life stages to better understand the ontogeny shift in this species. Snakes were grouped by age and sex, and venom pools were formed accordingly. Compositional analyses by one-dimensional electrophoresis (1-DE), chromatography, and mass spectrometry revealed that ontogenetic changes might be mostly related to phospholipase A2 (PLA2) and metalloproteases. Regarding the venoms functional aspect, proteolytic, L-amino acid oxidase, PLA2, and coagulant in vitro activities were assayed, but only the first and the last ones showed age-related changes, with the venom of snakes up to 1 year-old displaying lower proteolytic and higher coagulant activities, while those from 2 years-old onward presented the opposite relation. The venoms of 3 years-old snakes were exceptions to the compositional and functional pattern of adults as both venoms presented profiles similar to neonates. Sex-related differences were observed in specific groups and were not age-related. In vivo experiments (median lethal dose and hemorrhagic activity) were statistically similar between neonates and adults, however we verified that the adult venom killed mice faster comparing to the neonates. All venoms were mostly recognized by the antibothropic serum and displayed similar profiles to 1-DE in western blotting. In conclusion, the Brazilian lancehead venom showed ontogenetic shift in its composition and activities. Furthermore, this change occurred in snakes from 1 to 2 years-old, and interestingly the venom pools from 3 years-old snakes had particular characteristics, which highlights the importance of comprehensive studies to better understand venom variability.

Development of aqueous two-phase systems-based approaches for the selective recovery of metalloproteases and phospholipases A2 toxins from Crotalus molossus nigrescens venom.

Snake venoms are rich sources of proteins with potential biotechnological and pharmaceutical applications. Among them, metalloproteases (MPs) and phospholipases A2 (PLA2) are the most abundant. Their isolation involves a multistep chromatographic approach, which has proven to be effective, however implies high operating costs and long processing times. In this study, a cost-effective and simple method based on aqueous two-phase systems (ATPS) was developed to recover MPs and PLA2 from Crotalus molossus nigrescens venom. A system with PEG 400 g mol-1, volume ratio (VR) 1, tie line length (TLL) 25% w/w and pH 7 showed the best performance for PLA2 recovery. In systems with PEG 400 g mol-1, VR 1, TLL 15% w/w, pH 7 and 1 and 3% w/w of NaCl, selective recovery of MP subtype P-III was achieved; whereas, in a system with PEG 400 g mol-1, VR 1, TLL 25% w/w and pH 8.5, MP subtypes P-I and P-III were recovered. Due to their low costs, ethanol-salt systems were also evaluated, however, failed to differentially partition PLA2 and MPs. The use of ATPS could contribute to the simplification and cost reduction of protein isolation processes from snake venoms and other toxin fluids, as well as potentially aid their biochemical, proteomic and biological analyses.

Métodos quimiomecânicos no tratamento de lesões cariosas profundas: um estudo in vitro / Chemomechanical methods in the treatment of deep carious lesions: an in vitro study

Este trabalho teve como objetivo investigar as propriedades antimicrobianas de substâncias utilizadas em métodos quimiomecânicos e seus efeitos na dentina e em células pulpares. Uma lesão de cárie artificial em dentina foi desenvolvida em cavidades padronizadas realizadas em dentes bovinos com amostras de Streptococcus mutans (ATCC 25175) e Lactobacillus casei (ATCC 7463). As cavidades foram tratadas de acordo com os grupos: G1 - Tampão FosfatoSalino (PBS); G2 - Clorexidina (CHX); G3 ­ Papacárie®; G4 - Água ozonizada (O3) e G5 - Terapia Fotodinâmica (PDT). O depósito microbiano coletado foi diluído e cultivado para obtenção de colônias isoladas na técnica pour-plate. A atividade de metaloproteinases dentinárias gelatinases (MMP-2 e MMP-9) foi avaliada pelo ensaio de zimografia qualitativamente. A viabilidade celular foi avaliada em células pulpares após 24, 72 e 120h e a osteodiferenciação após 10 dias. A CHX e PDT apresentaram redução bacteriana em comparação aos demais grupos (p<0,05). O tratamento feito com PBS, CHX e PDT apresentou atividade gelatinolítica após o tratamento para as MMP-2 e MMP-9. A viabilidade celular reduziu em 120 h para todos os grupos em relação ao controle. CHX, O3 e PDT induziram maior osteodiferenciação em relação ao PBS e ao Papacárie. Concluiu-se que CHX e PDT promoveram leve diminuição da carga bacteriana na lesão cariosa artificial. Todos os tratamentos causaram, em parte, atividade gelatinolítica, por meio da expressão de MMP-2 e MMP-9. Apesar de diminuírem a viabilidade celular, nenhum tratamento interferiu com a diferenciação das células pulpares. A utilização dos métodos quimiomecânicos testados resultou em baixa redução bacteriana nas lesões cariosas artificiais. Concomitantemente, alguns desses tratamentos podem ativar metaloproteinases e interferir com funções essenciais de células pulpares.

This work aimed to investigate the antimicrobial properties of substances used in chemo mechanical methods and their effects on dentin and pulp cells. An artificial caries lesion was developed in standardized cavities performed in bovine teeth with strains of Streptococcus mutans (ATCC 25175) and Lactobacillus casei (ATCC 7463). The cavities were treated according to the following groups: G1 - Phosphate Buffer Saline (PBS); G2 - Chlorhexidine (CHX); G3 ­ Papacárie®; G4 - Ozonized water (O3) and G5 - Photodynamic Therapy (PDT). A microbial sample was collected, diluted, and cultivated to obtain isolated colonies through pour-plate technique. The activity of dentin gelatinase metalloproteinases (MMP-2 and MMP9) was qualitatively evaluated by zymography assay. Cell viability was evaluated in pulp cells after 24, 72, and 120h and osteodifferentiation after 10 days. CHX and PDT caused bacterial reduction compared to the other groups (p<0.05). PBS, CHX, and PDT showed gelatinolytic activity through the expression of MMP-2 and MMP-9. Cell viability was reduced at 120 h for all groups in comparison to control. CHX, O3, and PDT induced greater osteodifferentiation compared to PBS and Papacárie®. It was concluded that CHX and PDT promoted a slight decrease in bacterial load in the artificial carious lesion. All treatments caused, in part, gelatinolytic activity, through the expression of MMP-2 and MMP-9. Despite decreasing cell viability, no treatment interfered with the differentiation of pulp cells. The use of chemo mechanical methods has a slight biological significance in reduction of bacterial load in artificial carious lesions. In addition, some of these treatments can activate metalloproteinases and interfere with essential pulp cell functions.

Gingival Crevicular Fluid Zinc- and Aspartyl-Binding Protease Profile of Individuals with Moderate/Severe Atopic Dermatitis.

Atopic dermatitis (AD) is a protease-modulated chronic disorder with heterogenous clinical manifestations which may lead to an imprecise diagnosis. To date, there are no diagnostic protease tests for AD. We explored the gingival crevicular fluid (GCF) protease profile of individuals with moderate/severe AD compared to healthy controls. An exploratory case-control study was conducted. AD patients (n = 23) and controls (n = 21) were enrolled at the International Center for Clinical Studies, Santiago, Chile. Complete dermatological and periodontal evaluations (involving the collection of GCF samples) were made. The levels of 35 proteases were analyzed using a human protease antibody array in matching AD patients (n = 6) and controls (n = 6) with healthy periodontium. The GCF levels of zinc-binding ADAM8, ADAM9, MMP8, Neprilysin/CD10, aspartyl-binding Cathepsin E, serin-binding Protein convertase9, and uPA/Urokinase proteases were lower in moderate/severe AD patients compared to controls (p < 0.05). No inter-group differences in the levels of the other 28 proteases were found. MMP8, Cathepsin E, and ADAM9 were the biomarkers with the highest sensitivity and specificity regarding the detection of AD (p < 0.05). The area under receiver operating characteristic (ROC) curve for MMP8 was 0.83 and MMP8 + ADAMP9 was 0.90, with no significant differences (p = 0.132). A combined model of MMP8, Cathepsin E, and ADAM9 was not considered since it did not converge. Then, levels of MMP8 in GCF were determined using a multiplex bead immunoassay in 23 subjects with AD and 21 healthy subjects. Lower levels of MMP8 in the GCF from the AD group versus healthy group (p = 0.029) were found. This difference remained significant after adjustment by periodontitis (p = 0.042). MMP8 revealed the diagnostic potential to identify AD patients versus healthy controls, (ROC area = 0.672, p < 0.05). In conclusion, differences in the protease profile between AD and control patients were associated with MMP8, Cathepsin E, and ADAM9. Based on the multiplex assay results, MMP8 was lower in AD patients than controls, suggesting that MMP8 may be a diagnostic biomarker candidate.