Sympatric snail populations have been kept in the laboratory since the isolation of the parasite from the field. To evaluate the influence of the intermediate host in the infectivity of
, this ...allopatric strain was compared to two sympatric strains, from different geographical origins, and with different time of maintenance in the laboratory. Snail-trematode compatibility was accessed for a total of nine possible combinations (three snail populations, three schistosome strains), using different charges of parasite: 1, 5, 10, and 15 miracidia/snail. Each
strain was characterized according to its infectivity phenotype that reflects the efficiency of their infection mechanism and all
populations were characterized according to its (in)compatible phenotype that reflects the level of (un)susceptibility they display. For all host-parasite combinations tested the dose-response relation indicated a trend for an increase in the infectivity of
when higher miracidial doses were used. SmRES-2 presented the highest overall infectivity rate, especially in the SmRES-2/BgRES interaction with 15 miracidia/snail. However, SmRES was more infective to BgBAR than SmRES-2, indicating that SmRES strain was more infective at the first contact with this new host than after 2 years of interaction (SmRES-2). BgBAR presented the highest susceptibility to infection. SmRES and SmRES-2 are the same parasite strains. It seems that during these 2 years of interaction, BgBAR acted like a filter and shifted the compatibility polymorphism of the strain SmRES. SmRES-2 became more infective to BgRES (sympatric) than to BgBAR (allopatric), and conversely, SmRES was more infective to BgBAR (allopatric) than to BgRES (sympatric). This interplay suggests that epigenetic mechanisms are prompting these changes. This study concerns with infection of
snails from different Brazilian localities with
in allopatric and sympatric associations that will partially help in understanding the natural epidemiology of schistosomiasis within natural snail populations in watercourses. This work demonstrates that there is a shift on the compatibility polymorphism profile resulting from sympatric and allopatric interactions of
and
that constantly change during the time of interaction.
This study investigated the possible biological, biochemical and histological changes in Bradybaena similaris(Gastropoda: Pulmonata) infected by Heterorhabditis indica (Rhabditida: ...Heterorhabditidae), strain LPP1. Two groups of 16 snails were formed: the control group (unexposed) and the treated group, which was exposed for three weeks to infective juveniles (J3) of H. indica LPP1. The experiment was conducted in duplicate, using a total of 64 snails. After the exposure period, the snails were dissected to collect the hemolymph and tissues, for evaluation of the physiological changes caused by the infection. The number of eggs laid/snail and the viability of these eggs were also assessed as indicators of the reproductive activity of B. similaris. Intense glycogenolysis was accompanied by a significant reduction (p < 0.05) in the glucose content of the hemolymph of the exposed snails, indicating that infection by H. indica induces breakdown of the host's glycemic homeostasis. Significant variations (p < 0.05) in the lactate dehydrogenase activity occurred together with changes in the concentration of pyruvic and lactic acid in the hemolymph of the infected B. similaris snails, corroborating the transition from aerobic to anaerobic metabolism in the hosts. These metabolic alterations reflect the parasitic castration process in this interface. The results suggest that the use of H. indica LPP1 is a potential alternative for biological control of B. similaris.
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•H. indica LPP1 induce inversion in the oxidative metabolism of B. similaris.•Exposure by H. indica LPP1 changes the levels of glucose and glycogen in B. similaris.•H. indica LPP1 induces parasitic castration in B. similaris.•H. indica LPP1 increase the activity of LDH in B. similaris.
This study aimed to analyze the cerebellum of rats submitted to an experimental focal cerebral ischemia, by middle cerebral artery occlusion for 90 minutes, followed by reperfusion for 48 hours, ...associated with an alcoholism model.
Fifty adult Wistar rats were used, subdivided into five experimental groups: control group (C): animals submitted to anesthesia only; sham group (S): animals submitted to complete simulation of the surgical procedure; ischemic group (I): animals submitted to focal cerebral ischemia for 90 minutes followed by reperfusion for 48 hours; alcoholic group (A): animals that received daily absolute ethanol diluted 20% in water for four weeks; and, ischemic and alcoholic group (I + A): animals receiving the same treatment as group A and, after four weeks, submitted to focal cerebral ischemia for 90 minutes, followed by reperfusion for 48 hours. The cerebellum samples were collected and immunohistochemical analysis of Caspase-9 protein and serum analysis by RT-PCR of microRNAs miR-21, miR-126 and miR155 were performed.
The expression of Caspase-9 was higher in groups I, A and I + A. In the microRNAs analyses, miR-126 was higher in groups A and I + A, miR-155 was higher in groups I and I + A.
We conclude that apoptosis occurs in the cerebellar cortex, even if it is distant from the ischemic focus, and that microRNAs 126 and 155 show a correlation with cellular apoptosis in ischemic rats and those submitted to the chronic alcohol model.
Rhipicephalus microplus
is an important tick in tropical regions due to the high economic losses caused by its parasitism.
Metarhizium anisopliae
and
Beauveria bassiana
are well-known ...entomopathogenic fungi that can afflict
R. microplus
ticks. The development of new targets and strategies to control this parasite can be driven by studies of this tick’s physiology. Recently, it was reported that when exposed to adverse physiological conditions, ticks can activate fermentative pathways, indicating transition from aerobic to anaerobic metabolism. Nevertheless, the precise mechanism by which entomopathogenic fungi influence
R. microplus
metabolism has not been clarified, limiting understanding of the tick-fungus association. Thus, the present study aimed to evaluate the effect of infection of ticks by
M. anisopliae
and
B. bassiana
on the amount of selected carboxylic acids present in the hemolymph, enabling increased understanding of changes previously reported. The results showed preservation in the concentrations of oxalic, lactic, and pyruvic acids in the hemolymph 24 and 48 h after dropping from cattle; while there were variations in the concentration of these carboxylic acids after infection of female ticks to
M. anisopliae
and
B. bassiana
. Significant increases were observed in the concentration of oxalic and lactic acids and significant reduction of pyruvic acid for both observation times (24 and 48 h) after infection by entomopathogenic fungi. These results indicate that
B. bassiana
and
M. anisopliae
infection alters the basal metabolism of
R. microplus
females, resulting in the activation of fermentative pathways.
Introduction
Brain ischemia is a major cause of death and neurologic disability in many countries. It is a frequent clinical condition of difficult therapeutic solution mainly because its ...physiopathological studies are embarrassed by factors like the diversity of the anatomical location of the lesions, its etiology and clinical signs and symptoms. The alcoholism is a health problemin many societies,larger studies are needed on effects of alcohol associated with cerebral ischemia. It is known that neurons can die few days after stroke and some researchers suggest that apoptosis is the main physiopathological mechanism involved in delayed neuronal death.
Objectives
To evaluate the histopathological changes, morphometry, expression of apoptosis‐related proteins CASPASE3 and BCL2, serum expression of miR‐21 after experimental cerebral ischemia followed by reperfusion for 48 hours, with or without a model of chronic alcoholism.
Material and Methods
We used 50 Wistar rats, divided into 5 experimental groups: Control: only anesthetic procedure; Sham: complete simulation of the surgical procedure; Ischemia (I): focal cerebral ischemia for 90 minutes + reperfusion for 48 hours; Alcoholic(A): received daily absolute ethyl alcohol diluted to 20% in water for four weeks, and, Alcoholic and Ischemic (I + A): the same treatment in group A and I. The brain samples collected were processed for histopathological analysis (by light microscopy and transmission electron microscopy), morphometric (counting of neurons in the striatum), both by the technique of luxol fast blue, and immunohistochemistry (for protein expression of CASPASE3 and BCL2). The blood of the ventral tail artery was collected for analysis of expression of miR‐21 by qPCR.
Results
We observed histopathological changes in animals with a higher degree of ischemic and ischemic groups associated with alcoholism in three areas analyzed: swelling of neuronal cytoplasm, foamy nucleus, neural cells with pyknotic nuclei, interstitial edema and foci of inflammatory infiltrate. The neuronal loss was higher in the medial striatum of animals in groups I and I+A. The protein expression of CASPASE3 was higher than the expression of BCL2, especially in groups I and I + A for the two proteins. The expression of CASPASE3 was higher in the region corresponding to the penumbra. Histopathology revealed that the ischemic focus had a greater number of pyknotic nuclei suggestive of necrosis.
Conclusions
The histopathologic and morphometric changes observed mainly in the ischemic focus were correlated with the expression of CASPASE3, the greater the area of penumbra, and were more severe in the ischemic animals when associated with chronic alcoholism. The expression of BCL2 was slightly higher where histopathological changes and expression of CASPASE3 were less evident. The serum expression of miR‐21 was not indicative of ischemic and/or associated with chronic alcoholism.
This is from the Experimental Biology 2018 Meeting. There is no full text article associated with this published in The FASEB Journal.
Stroke is one of the main causes of death and disability worldwide. The great impact on the quality of life of the population and on the health system justifies that we seek relevant alternatives to ...reduce the incidence and improve the treatment and recovery of patients affected by this disease. Physical exercise appears as an important tool in this scenario, being already pointed out as a possible therapeutic approach for the prevention of non-contagious chronic diseases. In this context, biomarkers such as miRNAs that respond to physical exercise and are directly related to several epigenetic mechanisms appear. Therefore, explaining the molecular mechanisms involved during physical exercise will lead to a better understanding of each stimulus and the dose to be used to better respond to each situation, thus being a promising approach for the evolution of prescription and control of training and processes recovery from various diseases, including stroke. Forty-eight Wistar rats were used, divided into four experimental groups: control group, ischemia group, physical exercise group and exercise + ischemia group. Real-time PCR methodology was used to analyze the expression of miRNAs: miR-126, miR-133b and miR-221. In our study we observed a significant difference in the expression of miR- 221 between the control group and the others groups. However, microRNAs: miR-126 and miR-133b do not show significant differences in expression between groups.
Angiostrongylus cantonensis is a metastrongylid nematode that has a heteroxenous cycle, where snails act as intermediate hosts and the rodents Rattus rattus and Rattus novergicus are the definitive ...hosts. However, humans may act as accidental hosts presenting an atypical form of parasitism. This fact has motivated research to better understand systems of relationships involving A. cantonensis, targeting the control of species of gastropods that act as intermediary hosts.
For this, six groups were formed: three control groups (uninfected) and three infected groups, exposed to approximately 1200 L1 larvae of A. cantonensis. At the end of each week (1, 2, and 3 weeks), snails were dissected without anesthesia and the gonad-digestive gland (DGG) complex was separated for determination of oxygen consumption through high-resolution titration-injection respirometer (Oroboros, Oxygraph; Innsbruck, Austria).
The results indicate suppression of mitochondrial oxidative metabolism of the host and compromised in different mitochondrial respiratory states. This effect, mainly observed in the group exposed to 1 week of infection, showed a decrease of approximately 38% (2.78 ± 0.37 pmol O2/mg of tissue; P < 0.05), 41% (2.76 ± 0.34 pmol O2/mg of tissue; P < 0.05) e 46% (2.91 ± 0.36 pmol O2/mg of tissue; P < 0.05) in the basal oxygen consumption after sequential addition (P + M), succinate and (ADP) in the respiratory medium, differing significantly from the control group.
The results presented indicate that the prepatent infection by this metastrongylid impairs the aerobic oxidative metabolism of its host, causing a reduction in basal oxygen consumption. This effect, observed at the start of development of the parasites, indicates that this stage is the most critical for the success of the infection, and can be explained by a reduction of the mitochondrial density of the tissue analyzed, or also by suppression of enzyme centers related to the oxidative reactions.
To evaluate histopathological and ultrastructural changes and expression of proteins related to apoptosis CASPASE 3 and XIAP after experimental induction of temporary focal cerebral ischemia (90 ...minutes) due to obstruction of the middle cerebral artery in alcoholism model.
Forty adult Wistar rats were used, subdivided into 5 experimental groups: control group (C); Sham group (S); Ischemic group (I); Alcoholic group (A); and Ischemic and Alcoholized group (I+A): animals submitted to the same treatment of group A and after four weeks were submitted to focal cerebral ischemia during 90 minutes, followed by reperfusion of 48 hours. Were processed for histopathological analysis and immunohistochemistry (for the protein expression of CASPASE -3 and XIAP).
Greater histopathological changes were observed in the animals of groups I and I+A in the three areas analyzed. The neuronal loss was higher in the medial striatum region of the animals of groups I and I + A. The protein expression of CASPASE -3 was higher than that of XIAP in the groups I and I + A for both proteins.
The expression of XIAP was slightly higher where the histopathological changes and expression of CASPASE -3 was less evident.
Cerebral ischemia has not only a high mortality rate, which is the second leading cause of death worldwide, but is also responsible for severe disabilities in working age individuals, generating ...enormous public expending for treatment and rehabilitation of the affected individuals. The role of microRNAs in the pathophysiology of cerebral ischemia has been highlighted in current investigations. In addition, recent studies have also highlighted physical exercise as a possible protective factor both in the prevention and in the effects of cerebral ischemia, placing it as an important study resource. Thus, we investigated the role of physical exercise in experimental cerebral ischemia associated with the expression of microRNA-27b. 16 animals were used, divided into four experimental groups: Control, Physical Exercise, Cerebral Ischemia and Cerebral Ischemia associated with Physical Exercise. The real-time PCR methodology was used to analyze the expression of microRNA-27b. Although there were no statistically significant differences in the expression of microRNA-27b between the groups studied, the increased expression of microRNA-27b in the Physical Exercise group indicates its neuroprotective role in the pathophysiology of cerebral ischemia.
Previous studies from our group described the consequences of using ethanol on penile erection. Nevertheless, the molecular mechanisms surrounding microRNAs, apoptosis process and their relationship ...with erectile dysfunction associated with alcohol consumption are still poorly understood. The objective of this analysis was to evaluate the mechanism of apoptosis by the expression of AIF and PARP, as well as their regulatory microRNAs: miR-145, miR-210 and miR-486, in the corpus cavernosum of rats submitted to a semivoluntary alcoholism model. For this study 24 Wistar rats were divided into two groups: control (C) and treated with 20 % ethanol (A) for seven weeks. The corpus cavernosum samples were prepared for immunohistochemical analysis of AIF and PARP protein expression, and microRNAs miR-145, miR-210, miR-486 gene expression in cavernous tissue was performed by real time PCR. The immunohistochemical analysis showed little nuclear positive labeling for the protein PARP and AIF in the corpus cavernosum of control and ethanol treated animals. After analysis of miR-145, -210 and -486 microRNA expression in the 12 animals studied, no results were found with significant statistical difference between the control and alcoholized groups. The expression of AIF and PARP and their regulatory microRNAs involved in apoptotic process (miR-145, miR-210 and miR-486) were not altered in the corpus cavernosum of rats submitted to semivoluntary alcoholism.
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