Cinnamaldehyde Increases the Survival of Mice Submitted to Sepsis Induced by Extraintestinal Pathogenic Escherichia coli

Several natural products have been investigated for their bactericidal potential, among these, cinnamaldehyde. In this study, we aimed to evaluate the activity of cinnamaldehyde in the treatment of animals with sepsis induced by extraintestinal pathogenic E. coli. Initially, the E. coli F5 was incubated with cinnamaldehyde to evaluate the minimum inhibitory and minimum bactericidal concentration. Animal survival was monitored for five days, and a subset of mice were euthanized after 10 h to evaluate histological, hematological, and immunological parameters, as well as the presence of bacteria in the organs. On the one hand, inoculation of bacterium caused the death of 100% of the animals within 24 h after infection. On the other hand, cinnamaldehyde (60 mg/kg) was able to keep 40% of mice alive after infection. The treatment significantly reduced the levels of cytokines in serum and peritoneum and increased the production of cells in both bone marrow and spleen, as well as lymphocytes at the infection site. Cinnamaldehyde was able to reduce tissue damage by decreasing the deleterious effects for the organism and contributed to the control of the sepsis and survival of animals; therefore, it is a promising candidate for the development of new drugs.

The immunomodulatory activity of Chenopodium ambrosioides reduces the parasite burden and hepatic granulomatous inflammation in Schistosoma mansoni-infection

ETHNOPHARMACOLOGICAL RELEVANCE

Folk medicine reports have described the use of Chenopodium ambrosioides as an anti-inflammatory, analgesic, and anthelmintic herb. These effects, including its activity against intestinal worms, are already scientifically observed. However, the immunological mechanisms of this species in the treatment of Schistosoma mansoni infection are unknown.

AIM OF THE STUDY

To evaluate the immunological and anti-Schistosoma mansoni effects of a crude Chenopodium ambrosioides hydro-alcoholic extract (HCE).

MATERIALS AND METHODS

For the in vitro analysis, cercariae and adult worms were exposed to different concentrations (0 to 10,000 μg/mL) of the HCE. For the in vivo evaluation, Swiss mice were infected with 50 cercariae of S. mansoni and separated into groups according to treatment as follows: a negative control (without treatment), a positive control (treated with Praziquantel®), HCE1 Group (treated with HCE during the cutaneous phase), HCE2 Group (treated with HCE during the lung phase), HCE3 Group (treated with HCE during the young worm phase), and HCE4 Group (treated with HCE during the adult worm phase). The animals treated with HCE received daily doses of 50 mg/kg, by gavage, for seven days, corresponding to the different developmental stages of S. mansoni. For comparison, a clean control group (uninfected and untreated) was also included. All animals were euthanized 60 days post-infection to allow the following assessments to be performed: a complete blood cells count, counts of eggs in the feces and liver, the quantification of cytokines and IgE levels, histopathological evaluations of the livers, and the analysis of inflammatory mediators.

RESULTS

HCE treatment increased the mortality of cercariae and adult worms in vitro. The HCE treatment in vivo reduced the eggs in feces and liver. The number and area of liver granulomas, independent of the phase of treatment, were also reduced. The treatment with HCE reduced the percentage of circulating eosinophils, IgE, IFN-γ, TNF-α, and IL-4. In contrast, the treatment with the HCE, dependent on the phase, increased IL-10 levels and the number of peritoneal and bone marrow cells, mainly of T lymphocytes, B lymphocytes, and macrophages. This effect could be due to secondary compounds presents in this extract, such as kaempferol, quercetin and derivatives.

CONCLUSIONS

This study demonstrates that Chenopodium ambrosioides has antiparasitic and immunomodulatory activity against the different phases of schistosomiasis, reducing the granulomatous inflammatory profile caused by the infection and, consequently, improving the disease prognosis.

Pic-Producing Escherichia coli Induces High Production of Proinflammatory Mediators by the Host Leading to Death by Sepsis

Escherichia coli is an important pathogen responsible for a variety of diseases. We have recently shown that Pic, a serine protease secreted by E. coli, mediates immune evasion by the direct cleavage of complement molecules. The aim of this study was to investigate the action of a Pic-producing bacteria in a murine model of sepsis. Mice were infected with Pic-producing E. coli (F5) or F5∆pic mutant. Animal survival was monitored for five days, and a subset of mice was euthanized after 12 h for sample acquisition. The inoculation of Pic-producing bacteria induced 100% death within 24 h. The colony forming units count in the organs was significantly higher in F5. Hematological analysis showed a decrease of total leukocytes. Nitric oxide and cytokines were detected in serum, as well as on peritoneal lavage of the F5 group in higher levels than those detected in the other groups. In addition, immunophenotyping showed a decrease of activated lymphocytes and macrophages in the F5 group. Therefore, Pic represents an important virulence factor, allowing the survival of the bacterium in the bloodstream and several organs, as well as inducing a high production of proinflammatory mediators by the host, and concomitantly a cellular immunosuppression, leading to sepsis and death.

Prophylactic Treatment With Simvastatin Modulates the Immune Response and Increases Animal Survival Following Lethal Sepsis Infection

Chronic use of statins may have anti-inflammatory action, promoting immunomodulation and survival in patients with sepsis. This study aimed to analyze the effects of pretreatment with simvastatin in lethal sepsis induced by cecal ligation and puncture (CLP). Male Swiss mice received prophylactic treatment with simvastatin or pyrogen-free water orally in a single daily dose for 30 days. After this period, the CLP was performed. Naïve and Sham groups were performed as non-infected controls. Animal survival was monitored for 60 h after the CLP. Half of mice were euthanized after 12 h to analyze colony-forming units (CFUs); hematological parameters; production of IL-10, IL-12, IL-6, TNF-α, IFN-γ, and MCP-1; cell counts on peritoneum, bronchoalveolar lavage (BAL), bone marrow, spleen, and mesenteric lymph node; immunephenotyping of T cells and antigen presenting cells and production of hydrogen peroxide (H₂O₂). Simvastatin induced an increase in survival and a decrease in the CFU count on peritoneum and on BAL cells number, especially lymphocytes. There was an increase in the platelets and lymphocytes number in the Simvastatin group when compared to the CLP group. Simvastatin induced a greater activation and proliferation of CD4+ T cells, as well as an increase in IL-6 and MCP-1 production, in chemotaxis to the peritoneum and in H₂O₂ secretion at this site. These data suggest that simvastatin has an impact on the survival of animals, as well as immunomodulatory effects in sepsis induced by CLP in mice.

Anti-arthritic properties of crude extract from Chenopodium ambrosioides L. leaves

Objectives

To evaluate the effect of hydroalcoholic crude extract (HCE) from Chenopodium ambrosioides leaves on the development of type II collagen-induced arthritis (CIA) and on pro-inflammatory cytokine balance.

Methods

Collagen-induced arthritis was induced in DBA1/J mice. On the 21st day, the mice were treated orally with HCE or methotrexate, daily. Six weeks after beginning the treatment, the following measures were determined: lymphoid organs cell numbers, percentage of blood cells, IL-6, IFN-γ, TNF-α and IL-17 serum concentrations, activity of hepatic and kidney glutathione S-transferase, hepatic 7-ethoxyresorufin-O-deethylase activity, bone density and histopathology.

Key findings

Treatment of CIA mice with HCE 5 mg/kg (HCE5) reduced the percentage of neutrophils and macrophages and the number of bone marrow cells and increased the lymphocyte numbers and the inguinal lymph node cellularity. This treatment inhibited the serum concentration of IL-6 and TNF-α, which may be related to the preservation of bone density and to the slight thickening of periarticular tissues, with minimal fibrosis and fibroblast proliferation in the joints. The CIA group presented advanced articular erosion and synovial hyperplasia. Phytochemical analysis showed mainly flavonols.

Conclusions

HCE5 presented anti-arthritic potential and reduced IL-6 and TNF-α, which participate directly in the development and maintenance of the inflammatory process in rheumatoid arthritis.

Chenopodium ambrosioides L. Improves Phagocytic Activity and Decreases Bacterial Growth and the Systemic Inflammatory Response in Sepsis Induced by Cecal Ligation and Puncture

Chenopodium ambrosioides L. (Amaranthaceae) is often used in different kinds of vegetal preparations for medicinal purposes in many clinical situations. Some studies have demonstrated its anti-inflammatory and immunomodulatory properties. The aim of this work was to investigate the effect of prophylactic treatment with the hydroalcoholic crude extract (HCE) of C. ambrosioides and its hexanic fraction (HEX) on the control of bacterial growth, the activation of phagocytes and the control of the systemic inflammatory response in a sepsis experimental model. Animals were divided into three groups (n = 5/group): Control, which received only NaCl 0.9% solution; HCE, which received the crude extract; and HEX, which received the HEX of the extract. The animals received saline, HCE or HEX (5 mg/kg), subcutaneously (SC), 6 h before cecal ligation and puncture (CLP). Twelve hours after the CLP, the blood was collected to measure the serum cytokines and the animals were killed for the evaluation of colony-forming units (CFUs), cellular influx, and activation of phagocytes in the peritoneal cavity, measured by the secretion of hydrogen peroxide and nitric oxide production. The results showed that only HEX treatment inhibited bacterial growth in the peritoneum and inflammatory cellular influx, especially influx of macrophages and neutrophils. However, HCE and HEX treatments increased ex vivo hydrogen peroxide secretion and nitric oxide production by phagocytes and decreased the pro-inflammatory cytokines in the serum, indicating a systemic anti-inflammatory effect of both. In conclusion, C. ambrosioides treatment decreases bacterial growth likely by activation of phagocytes and, in parallel, ameliorates the general state of mice by reducing the systemic inflammatory response usually observed in sepsis.

[The prevalence of intestinal parasitism in native villages of the Tembé tribe, the Brazilian eastern Amazon]

To determine the prevalence of intestinal parasitism in the Tembé settlements, parasitological examination was performed in December 1996 in the entire population (93 Indians). Hookworms were found in 29.0%, A. lumbricoides in 34.4%, E. histolytica in 12.9%, and G. lamblia in 4.3% of the individuals. The Turé-Mariquita settlement had the highest prevalence of hookworms and A. lumbricoides, while Acará-Mirim had the highest prevalence of E. histolytica and G. lamblia. No differences in mean age were found between Indians with parasites and Indians without parasites. The association between intestinal parasites and sex was nonsignificant, except for the prevalence of hookworms, which was very high in males (38.6%) compared to females (20.4%). The study showed a high prevalence of some intestinal parasites in the Tembé settlements, indicating that primary and secondary health measures should taken immediately for the prevention of intestinal parasitoses.