Activity of cholinesterases and adenosine deaminase in blood and serum of rats experimentally infected with Trypanosoma cruzi

Stigma, participation restriction and mental distress in patients affected by leprosy, cutaneous leishmaniasis and Chagas disease: a pilot study in two co-endemic regions of eastern Colombia

Background

Leprosy, cutaneous leishmaniasis (CL) and Chagas disease (CD) are neglected tropical diseases with a high psychosocial burden (PSB). These conditions are endemic in Norte de Santander and Arauca in Colombia, but data on the related PSB are scarce. Therefore, we assessed mental distress, participation restriction and stigma among CD, CL and leprosy patients.

Methods

In 2018, 305 leprosy, CD or CL patients were interviewed using a self-report questionnaire to assess mental distress, participation scale for participation restriction and explanatory model interview catalogue (EMIC) for stigma. Descriptive statistics and the significance of median score differences were compared.

Results

Fifty percent of CD patients and 49% of leprosy patients exhibited mental distress, percentages which were significantly higher than that of CL (26%). Twenty-seven percent of leprosy patients experienced participation restriction, which was lower for CL (6%) and CD (12%). Median EMIC scores were significantly higher for leprosy patients than for CD (27%) and CL (17%) patients.

Conclusions

We found high levels of PSB among leprosy, CD and CL patients. Mental distress was highest among CD patients. Participation restriction and stigma were more prevalent in leprosy patients. Rural residence or lower educational status may impact PSB. Further investigation is needed to formulate evidence-based, holistic interventions.

Correlation of plasma butyrylcholinesterase concentration with Acethylcholinesterase H353N polymorphism in the inflammatory response of Chagas disease patients

Trypanosoma cruzi infection triggers an intense production of pro-inflammatory cytokines mediated by T helper 1 lymphocytes, inducing the anti-inflammatory reflex of acetylcholine (ACh). The ACh concentration modulation is associated to the two major esterases, the acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). AChE H353N protein polymorphism is related to low Chagas chronic disease prognostic. In order to evaluate the correlation of plasmatic BuChE concentration and the presence of AChE H353N polymorphism in Chagas disease patients and healthy individuals, we studied two groups of individuals, one of 61 Chagas disease patients and another of 74 healthy individuals. Plasma concentration of BuChE was measured by the chemiluminescent method and AChE H353N polymorphism was investigated by PCR-RFLP and sequencing of the respective encoding AChE gene fragment. The BuChE concentration was statistically higher in Chagas disease patients, with no AChE genotype significant influence. AChE genotypes YT*A/YT*A, YT*A/YT*B and YT*B/YT*B, respectively, were expressed in 53 (86.88%), 7 (11.46%) and one (1.64%) chagasic patients, and in 68 (91.89%), 6 (8.10%) and none healthy individuals. BuChE activity may represent an important marker for chronic Chagas disease inflammatory process and prognostic. Lower BuChE concentration correlated with AChE YT*B allele, although without statistical power.

Occurrence of oxidative stress in dairy cows seropositives for Brucella abortus

Bovine brucellosis is an important zoonotic disease caused by the bacterium Brucella abortus that leads to economic losses due to animal discard and commercial restrictions. Since positive animals for brucellosis are culled, little is known about the pathogenesis of this disease. Therefore, the aims of this study were to evaluate possible changes in the activity of deaminase adenosine (ADA) and the oxidative stress in cows seropositives for brucellosis (Experiment I), and to evaluate the seroprevalence of B. abortus in dairy cows from the Western state of Santa Catarina, Southern Brazil (Experiment II). The Experiment I evaluated 20 pregnant cows: ten seropositives for B. abortus and ten seronegatives that were used as controls. The ADA activity and markers of oxidative stress (TBARS, catalase (CAT) and superoxide dismutase (SOD)) were evaluated in these animals. A reduction in the activity of ADA and catalase enzymes in seropositive animals was observed (p < 0.001). Conversely, there was an increase in TBARS levels and superoxide dismutase activity in cows infected by B. abortus (p < 0.001). The presence of oxidative stress and a reduction of ADA might be related to the modulation of the inflammatory response. The experiment II was performed due to a high number of herds with restrictions imposed by cases of brucellosis in the state of Santa Catarina in the last two years, and thus, the seroprevalence for B. abortus was evaluated in 1242 serum samples of cows of 69 herds. The serodiagnosis was performed using two tests: buffered acidified antigen and 2-mercaptoethanol. However, none of the serum samples were positive for B. abortus. Although we did not find seropositive animals for brucellosis in our study, the disease still requires continued surveillance, due to its economic impact, and to the oxidative stress caused by it, which may have contributed to cases of abortion in three seropositive cows (Experiment I) in the final third of the gestation.

Demodex canis regulates cholinergic system mediated immunosuppressive pathways in canine demodicosis

Demodex canis infestation in dogs remains one of the main challenges in veterinary dermatology. The exact pathogenesis of canine demodicosis is unknown but an aberration in immune status is considered very significant. No studies have underpinned the nexus between induction of demodicosis and neural immunosuppressive pathways so far. We have evaluated the involvement of cholinergic pathways in association with cytokines regulation as an insight into the immuno-pathogenesis of canine demodicosis in the present study. Remarkable elevations in circulatory immunosuppressive cytokine interleukin-10 and cholinesterase activity were observed in dogs with demodicosis. Simultaneously, remarkable reduction in circulatory pro-inflammatory cytokine tumour necrosis factor-alpha level was observed in dogs with demodicosis. Findings of the present study evidently suggest that Demodex mites might be affecting the cholinergic pathways to induce immunosuppression in their host and then proliferate incessantly in skin microenvironment to cause demodicosis.

Purinergic enzymatic activities in lymphocytes and cardiomyocytes of mice acutely infected by Trypanosoma cruzi modulating the inflammatory responses

The aim of this study was to evaluate the activity of purinergic enzymes in lymphocytes and cardiac tissue of mice experimentally infected by Trypanosoma cruzi. Twelve female mice were used, divided into two groups (n = 6): uninfected and infected. On day 12 post-infection (PI), the animals were anesthetized and after euthanized, and samples were collected for analyses. Infected mice showed reduction in erythrocyte counts, hematocrit and hemoglobin concentration, as well as reduced number of total leukocytes in consequence of neutrophilia (P < 0.01). The number of monocytes increased in infected mice (P < 0.001), however the number of lymphocytes and eosinophils did not differ between groups (P > 0.05). The E-NTPDase (ATP and ADP substrate) and E-ADA activities in lymphocytes increased significantly in mice infected by T. cruzi (P < 0.01). In the heart, multiple pseudocysts containing amastigotes within cardiomyocytes were observed, as well as focally extensive severe necrosis associated with diffuse moderate to severe inflammatory infiltrate of lymphocytes. Although, the NTPDase activity (ATP and ADP substrate) in the cardiac homogenate did not differ between groups, a reduction on 5'-nucleotidase activity (P < 0.001) and an increase in the ADA activity in infected animals (P < 0.05) were observed. Thus, animals infected by T. cruzi experienced the disease, i.e., showed anemia, leucopenia, and heart lesions. Associated with this, purinergic enzymes showed altered activities, which might be related to the modulation of the inflammatory response.

Activity of cholinesterases, pyruvate kinase and adenosine deaminase in rats experimentally infected by Fasciola hepatica: Influences of these enzymes on inflammatory response and pathological findings

The aim of this study was to investigate acetylcholinesterase (AChE) in total blood and liver tissue; butyrylcholinesterase (BChE) in serum and liver tissue; adenosine deaminase (ADA) in serum and liver tissue; and pyruvate kinase (PK) in liver tissue of rats experimentally infected by Fasciola hepatica. Animals were divided into two groups with 12 animals each, as follows: group A (uninfected) and group B (infected). Samples were collected at 20 (A1 and B1;n=6 each) and 150 (A2 and B2; n=6 each) days post-infection (PI). Infected animals showed an increase in AChE activity in whole blood and a decrease in AChE activity in liver homogenates (P<0.05) at 20 and 150 days PI. BChE and PK activities were decreased (P<0.05) in serum and liver homogenates of infected animals at 150 days PI. ADA activity was decreased in serum at 20 and 150 days PI, while in liver homogenates it was only decreased at 150 days PI (P<0.05). Aspartate aminotransferase and alanine aminotransferase activities in serum were increased (P<0.05), while concentrations of total protein and albumin were decreased (P<0.05) when compared to control. The histological analysis revealed fibrous perihepatitis and necrosis. Therefore, we conclude that the liver fluke is associated with cholinergic and purinergic dysfunctions, which in turn may influence the pathogenesis of the disease.

Relationship between butyrylcholinesterase activity and liver injury in mice acute infected with Toxoplasma gondii

This study aimed to investigate the butyrylcholinesterase (BChE) activity in mice experimentally infected with Toxoplasma gondii during the acute phase. Twenty mice were divided in two groups with 10 animals each: group A was composed of uninfected mice while group B was formed by rodents infected with T. gondii. Five days after infection, blood was collected and serum separated, and fragments of liver and brain were obtained. In serum and liver homogenate was noted a significant reduction (P<0.05) in BChE activity in infected mice when compared with uninfected ones. In serum was observed an increase in the activity of alanine aminotransferase and urea, associated with reduction in alkaline phosphatase activity and in the levels of total protein and albumin. Histologically, there were foci of necrosis and parasites in the forms of tachyzoites and cysts, with bradyzoites in liver samples of infected animals. Based on these results, we conclude that toxoplasmosis reduces BChE activity in mice, and this alteration is probably related to the liver damage caused by the parasitism. Therefore, this enzymatic alteration can directly contribute to the pathogenesis of the disease.

Purinergic system ecto-enzymes participate in the thromboregulation of patients with indeterminate form of Chagas disease

Chagas disease (CD) is a chronic and endemic illness caused by the parasite Trypanosoma cruzi. Microvascular disturbances play an important role in the progress of the disease. The purinergic signaling system participates in regulatory functions, such as immunomodulation, neuroprotection, and thromboregulation. This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface and the platelet aggregation profile from patients with indeterminate form of Chagas disease (IFCD). Thirty patients diagnosed with IFCD and 30 healthy subjects were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), ecto-5'-nucleotidase (E-5'-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals as well as the platelet aggregation. Results demonstrated an increase of 21 % in the E-NPP activity and 30 % in the E-5'-NT activity in IFCD group (P < 0.05); however, a decrease of 34 % in the E-ADA activity was determined in the same group (P < 0.001). A significant decrease of 12.7 % and 12.8 % in the platelet aggregation of IFCD group in two different concentrations of ADP (5 and 10 μM) was observed, respectively (P < 0.05). Increased E-NPP and E-5-NT activities as well as decreased E-ADA activity in platelets of patients with IFCD contributed to decrease platelet aggregation, suggesting that the purinergic system is involved in the thromboregulation process in these patients, since adenosine (the final product of ATP hydrolysis) has cardioprotective and vasodilator effects that prevent the clinical progress of the disease.