Bothrops jararaca Snake Venom Inflammation Induced in Human Whole Blood: Role of the Complement System.

The clinical manifestations of envenomation by Bothrops species are complex and characterized by prominent local effects that can progress to tissue loss, physical disability, or amputation. Systemic signs can also occur, such as hemorrhage, coagulopathy, shock, and acute kidney failure. The rapid development of local clinical manifestations is accompanied by the presence of mediators of the inflammatory process originating from tissues damaged by the bothropic venom. Considering the important role that the complement system plays in the inflammatory response, in this study, we analyzed the action of Bothrops jararaca snake venom on the complement system and cell surface receptors involved in innate immunity using an ex vivo human whole blood model. B. jararaca venom was able to induce activation of the complement system in the human whole blood model and promoted a significant increase in the production of anaphylatoxins C3a/C3a-desArg, C4a/C4a-desArg, C5a/C5a-desArg and sTCC. In leukocytes, the venom of B. jararaca reduced the expression of CD11b, CD14 and C5aR1. Inhibition of the C3 component by Cp40, an inhibitor of C3, resulted in a reduction of C3a/C3a-desArg, C5a/C5a-desArg and sTCC to basal levels in samples stimulated with the venom. Exposure to B. jararaca venom induced the production of inflammatory cytokines and chemokines such as TNF-α, IL-8/CXCL8, MCP-1/CCL2 and MIG/CXCL9 in the human whole blood model. Treatment with Cp40 promoted a significant reduction in the production of TNF-α, IL-8/CXCL8 and MCP-1/CCL2. C5aR1 inhibition with PMX205 also promoted a reduction of TNF-α and IL-8/CXCL8 to basal levels in the samples stimulated with venom. In conclusion, the data presented here suggest that the activation of the complement system promoted by the venom of the snake B. jararaca in the human whole blood model significantly contributes to the inflammatory process. The control of several inflammatory parameters using Cp40, an inhibitor of the C3 component, and PMX205, a C5aR1 antagonist, indicates that complement inhibition may represent a potential therapeutic tool in B. jararaca envenoming.

Complement system inhibition modulates the inflammation induced by the venom of premolis semirufa, an Amazon rainforest Moth Caterpillar

The caterpillar of the Premolis semirufa moth, commonly called Pararama, is found in the Brazilian Amazon region. Contact with the hairs can cause a chronic inflammatory reaction, termed “pararamosis”. To date, there is still no specific treatment for pararamosis. In this study, we used a whole human blood model to evaluate the involvement of the complement in the proinflammatory effects of P. semirufa hair extract, as well as the anti-inflammatory potential of complement inhibitors in this process. After treatment of blood samples with the P. semirufa hair extract, there was a significant increase in the generation of soluble terminal complement complex (sTCC) and anaphylatoxins (C3a, C4a, and C5a), as well as the production of the cytokines TNF-α and IL-17 and the chemokines IL-8, RANTES, MIG, MCP-1, and IP-10. The inhibition of C3 with compstatin significantly decreased IL-17, IL-8, RANTES, and MCP-1 production. However, the use of the C5aR1 antagonist PMX205 promoted a reduction in the production of IL-8 and RANTES. Moreover, compstatin decreased CD11b, C5aR1, and TLR2 expression induced by P. semirufa hair extract in granulocytes and CD11b, TLR4, and TLR2 in monocytes. When we incubated vascular endothelial cells with extract-treated human plasma, there was an increase in IL-8 and MCP-1 production, and compstatin was able to decrease the production of these chemokines. C5aR1 antagonism also decreased the production of MCP-1 in endothelial cells. Thus, these results indicate that the extract of the Pararama bristles activates the complement system and that this action contributes to the production of cytokines and chemokines, modulation of the expression of surface markers in leukocytes, and activation of endothelial cells.

Bothrops jararaca snake venom inflammation induced in human whole blood: role of the complement system

The clinical manifestations of envenomation by Bothrops species are complex and characterized by prominent local effects that can progress to tissue loss, physical disability, or amputation. Systemic signs can also occur, such as hemorrhage, coagulopathy, shock, and acute kidney failure. The rapid development of local clinical manifestations is accompanied by the presence of mediators of the inflammatory process originating from tissues damaged by the bothropic venom. Considering the important role that the complement system plays in the inflammatory response, in this study, we analyzed the action of Bothrops jararaca snake venom on the complement system and cell surface receptors involved in innate immunity using an ex vivo human whole blood model. B. jararaca venom was able to induce activation of the complement system in the human whole blood model and promoted a significant increase in the production of anaphylatoxins C3a/C3a-desArg, C4a/C4a-desArg, C5a/C5a-desArg and sTCC. In leukocytes, the venom of B. jararaca reduced the expression of CD11b, CD14 and C5aR1. Inhibition of the C3 component by Cp40, an inhibitor of C3, resulted in a reduction of C3a/C3a-desArg, C5a/C5a-desArg and sTCC to basal levels in samples stimulated with the venom. Exposure to B. jararaca venom induced the production of inflammatory cytokines and chemokines such as TNF-α, IL-8/CXCL8, MCP-1/CCL2 and MIG/CXCL9 in the human whole blood model. Treatment with Cp40 promoted a significant reduction in the production of TNF-α, IL-8/CXCL8 and MCP-1/CCL2. C5aR1 inhibition with PMX205 also promoted a reduction of TNF-α and IL-8/CXCL8 to basal levels in the samples stimulated with venom. In conclusion, the data presented here suggest that the activation of the complement system promoted by the venom of the snake B. jararaca in the human whole blood model significantly contributes to the inflammatory process. The control of several inflammatory parameters using Cp40, an inhibitor of the C3 component, and PMX205, a C5aR1 antagonist, indicates that complement inhibition may represent a potential therapeutic tool in B. jararaca envenoming.

Bothrops lanceolatus snake (Fer-de-lance) venom triggers inflammatory mediators' storm in human blood.

Systemic increased inflammatory mediators' levels are a hallmark in a plethora of pathological conditions, including thrombotic diseases as the envenomation by Bothrops lanceolatus snake. Multiple organ infarctions, which are not prevented by anticoagulant therapy, are the main cause of death on this envenomation. However, the potential mechanisms involved in these systemic reactions are underexplored. This study aimed to explore the potential systemic events which could contribute to thrombotic reactions on the envenomation by B. lanceolatus in an ex vivo human whole-blood model. B. lanceolatus venom elicited an inflammatory reaction, which was characterized by a strong complement activation, since we detected high C3a, C4a and C5a anaphylatoxins levels. Besides, the venom promoted soluble Terminal Complement Complex (sTCC) assembly. Complement activation was accompanied by intense lipid mediators' release, which included LTB4, PGE2 and TXB2. In addition, in the blood exposed to B. lanceolatus venom, we detected IL-1ß, IL-6 and TNF-α interleukins production. Chemokines, including CCL2, CCL5 and CXCL8 were upregulated in the venom presence. These outcomes show that B. lanceolatus venom causes a strong inflammatory reaction in the blood favoring a potential setting to thrombi formation. Thus, inhibiting inflammatory mediators or their receptors may help in the envenomed patients' management.

Bothrops lanceolatus snake (Fer-de-lance) venom triggers inflammatory mediators’ storm in human blood

Systemic increased inflammatory mediators’ levels are a hallmark in a plethora of pathological conditions, including thrombotic diseases as the envenomation by Bothrops lanceolatus snake. Multiple organ infarctions, which are not prevented by anticoagulant therapy, are the main cause of death on this envenomation. However, the potential mechanisms involved in these systemic reactions are underexplored. This study aimed to explore the potential systemic events which could contribute to thrombotic reactions on the envenomation by B. lanceolatus in an ex vivo human whole-blood model. B. lanceolatus venom elicited an inflammatory reaction, which was characterized by a strong complement activation, since we detected high C3a, C4a and C5a anaphylatoxins levels. Besides, the venom promoted soluble Terminal Complement Complex (sTCC) assembly. Complement activation was accompanied by intense lipid mediators’ release, which included LTB4, PGE2 and TXB2. In addition, in the blood exposed to B. lanceolatus venom, we detected IL-1β, IL-6 and TNF-α interleukins production. Chemokines, including CCL2, CCL5 and CXCL8 were upregulated in the venom presence. These outcomes show that B. lanceolatus venom causes a strong inflammatory reaction in the blood favoring a potential setting to thrombi formation. Thus, inhibiting inflammatory mediators or their receptors may help in the envenomed patients’ management.

Persistence and intra-host genetic evolution of Zika virus infection in symptomatic adults: a special view in the male reproductive system

We followed the presence of Zika virus (ZIKV) in four healthy adults (two men and two women), for periods ranging from 78 to 298 days post symptom onset. The patients were evaluated regarding the presence of the virus in different body fluids (blood, saliva, urine and semen), development of immune responses (including antibodies, cytokines and chemokines), and virus genetic variation within samples collected from semen and urine during the infection course. The analysis was focused primarily on the two male patients who shed the virus for up to 158 days after the initial symptoms. ZIKV particles were detected in the spermatozoa cytoplasm and flagella, in immature sperm cells and could also be isolated from semen in cell culture, confirming that the virus is able to preserve integrity and infectivity during replication in the male reproductive system (MRS). Despite the damage caused by ZIKV infection within the MRS, our data showed that ZIKV infection did not result in infertility at least in one of the male patients. This patient was able to conceive a child after the infection. We also detected alterations in the male genital cytokine milieu, which could play an important role in the replication and transmission of the virus which could considerably increase the risk of ZIKV sexual spread. In addition, full genome ZIKV sequences were obtained from several samples (mainly semen), which allowed us to monitor the evolution of the virus within a patient during the infection course. We observed genetic changes over time in consensus sequences and lower frequency intra-host single nucleotide variants (iSNV), that suggested independent compartmentalization of ZIKV populations in the reproductive and urinary systems. Altogether, the present observations confirm the risks associated with the long-term replication and shedding of ZIKV in the MRS and help to elucidate patterns of intra-host genetic evolution during long term replication of the virus.

Persistence and intra-host genetic evolution of Zika virus infection in symptomatic adults: a special view in the male reproductive system

We followed the presence of Zika virus (ZIKV) in four healthy adults (two men and two women), for periods ranging from 78 to 298 days post symptom onset. The patients were evaluated regarding the presence of the virus in different body fluids (blood, saliva, urine and semen), development of immune responses (including antibodies, cytokines and chemokines), and virus genetic variation within samples collected from semen and urine during the infection course. The analysis was focused primarily on the two male patients who shed the virus for up to 158 days after the initial symptoms. ZIKV particles were detected in the spermatozoa cytoplasm and flagella, in immature sperm cells and could also be isolated from semen in cell culture, confirming that the virus is able to preserve integrity and infectivity during replication in the male reproductive system (MRS). Despite the damage caused by ZIKV infection within the MRS, our data showed that ZIKV infection did not result in infertility at least in one of the male patients. This patient was able to conceive a child after the infection. We also detected alterations in the male genital cytokine milieu, which could play an important role in the replication and transmission of the virus which could considerably increase the risk of ZIKV sexual spread. In addition, full genome ZIKV sequences were obtained from several samples (mainly semen), which allowed us to monitor the evolution of the virus within a patient during the infection course. We observed genetic changes over time in consensus sequences and lower frequency intra-host single nucleotide variants (iSNV), that suggested independent compartmentalization of ZIKV populations in the reproductive and urinary systems. Altogether, the present observations confirm the risks associated with the long-term replication and shedding of ZIKV in the MRS and help to elucidate patterns of intra-host genetic evolution during long term replication of the virus.

Effects of Cachaça, a typical Brazilian alcoholic beverage, on alveolar bone loss and density: a study in peripubertal rats.

OBJECTIVE: The aim of the present study was to assess the impact of chronic consumption of Cachaça on alveolar bone loss (BL) induced by ligature and on alveolar bone density (BD) in peripubertal rats. DESIGN: Male Wistar rats were assigned into one of the following groups: CONTROL: non-ingestion of Cachaça (n=15); Cachaça: ingestion of ascending concentrations of Cachaça during 100 days (n=15). 70th day after the beginning of Cachaça ingestion, one first mandibular molar received a ligature while the contralateral tooth was left unligated. After 30 days, the rats were killed. BL, BD, the positive cells for tartrate-resistant acid phosphatase (TRAP), receptor activator of NF-κB ligand (RANKL) and osteoprotegerin (OPG) were analyzed in the furcation area of the ligated and unligated mandibular molars. RESULTS: The Cachaça group presented greater BL (0.75±0.1mm(2) for Cachaça and 0.66±0.1mm(2) for control group, respectively) and number of RANKL and OPG+ cells and lower BD (60.3±4.2% for Cachaça and 76.8±3.8% for control group, respectively) and number of TRAP+ cells around ligated teeth (p<0.05), when compared to the control group. The Cachaça group (0.42±0.02mm(2)) also presented a higher BL around unligated teeth when compared to control group (0.31±0.05mm(2)). CONCLUSIONS: Cachaça consumption per se and in the presence of ligature negatively affects alveolar bone by increasing the alveolar BL and reducing BD.