20 research outputs found
In Vitro And In Vivo Phenotypic Studies To Characterize Blastocystis Sp. Subtype 3 (ST3) Isolated From Asymptomatic Individuals, Symptomatic And Irritable Bowel Syndrome (IBS) Patients / Nanthiney Devi Ragavan
The role of intestinal infection mediated-inflammation in the pathogenesis of
irritable bowel syndrome (IBS) remains uncertain. Blastocystis sp. is the most common
gut parasite found in the intestinal tract of humans. Its association with IBS is
controversial, possibly as a result of irregular shedding of parasites in stool. The study
aimed to screen for Blastocystis sp. in stool aspirate and stool samples in adult patients
with and without IBS undergoing colonoscopy and measure the interleukin levels (IL-3,
IL-5 and IL-8). This study suggests that stool aspirate sample may be a better method
for sample collection for detecting Blastocystis sp. by PCR method during colonoscopy.
Subtype 3 (ST3) was found to be the most predominant subtype. An increase in the
interleukin levels demonstrates that Blastocystis sp. does have an effect in the immune
system. The phenotypic characteristics of Blastocystis sp. ST3 isolated from
asymptomatic individuals, symptomatic and irritable bowel syndrome (IBS) patients
were analyzed. Blastocystis sp. ST3 isolated from IBS patients was shown to have a
distinct growth profile, strong aggregation and clumping of parasites when stained with
Modified Fields’ stain with outer surface showing a greater binding affinity towards
FITC Con A in symptomatic than asymptomatic isolates. Ultrastructural studies also
showed that the parasite isolated from IBS patients possesses a rough, coarse surface
with thicker surface coat and the presence of electron dense material. Ileum from the
rabbit and Balb/C mice showed the highest number of muscle twitching when
introduced with Blastocystis sp. ST3 antigen (Blasto-Ag ST3) derived from Blastocystis
sp. infected IBS patient. The present study is the first to demonstrate the phenomenon of
gut environment facilitating adaptation of parasites possibly for survival leading to
phenotypic differences for Blastocystis sp. within a particular subtype. An in vitro
model to study the pathogenicity of Blastocystis sp. ST3 was designed by comparing the
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degree of mucosal sloughing, inflammation and necrosis of tissue of the Wistar rat’s
ileum, caecum, colon and rectum orally inoculated with Blastocystis sp. ST3 cysts
isolated from asymptomatic individuals, symptomatic and IBS patients. This is the first
study to provide evidence that occurrence of mucosal sloughing, inflammation and
necrosis was seen to be higher in IBS group compared to symptomatic and
asymptomatic group. This study supports the earlier findings that intestinal
inflammation does play an important role in the clinical manifestation of IBS patients.
With this, the association between Blastocystis sp. infection and inflammation was
investigated. Wnt signaling pathway had been linked with inflammation and colorectal
cancer. In the present study, we attempted to assess the effects Blasto-Ag derived from
non-IBS and IBS patients respectively on the growth and gene expression of cancer
cells, HCT116 in vitro compared with normal cells, CCD-18Co. The results revealed
that the proliferation rate and migration of cells for both normal and cancer cells were
significantly higher when induced with IBS Blasto-Ag ST3 compared to non-IBS
Blasto-Ag ST3 implying that it may play a role in advancing colorectal tumor
progression in IBS patients. Wnt analysis showed that a large number of canonical Wnts
involved in the canonical pathway for both normal and cancer cells upon exposure of
both the non-IBS and IBS Blasto-Ag ST3. However, IBS Blasto-Ag ST3 showed a
greater effect on both cells compared to non-IBS Blasto-Ag ST3. The present study also
conclusively provides evidence for the first time the factors such as the frequency of
toilet visit in a day, the timing of toilet visit, the stool forms, and patient’s moods as
well as emotions can influence the shedding pattern of Blastocystis sp. cysts in an IBS
patient. Stools should be collected in the morning; especially samples should be taken
from the semi-solid form every time one visits the toilet even within a day for
diagnostic purposes
Levels of serum for IL 8, IL 3 and IL 5.
<p>Data is given in mean ± SD. **P < 0.05 is the comparison done against non-IBS group. <sup>b</sup>P < 0.05 is the comparison done against IBS group.</p
Pearson’s correlation between the urinary biochemical variables in AOM-treated controls and rats treated with AOM + co-infection with <i>Blastocystis</i>.
<p>Pearson’s correlation between the urinary biochemical variables in AOM-treated controls and rats treated with AOM + co-infection with <i>Blastocystis</i>.</p
Representative histological Hematoxylin and Eosin (H and E) staining of goblet cells of small intestine (x 100 magnifications).
<p>Control; (B) AOM; (C) <i>Blastocystis</i>; (D) AOM + Blastocystis cyst.</p
Representative histological Hematoxylin and Eosin (H and E) staining of caecum.
<p>(A) Control(x 40 magnifications); (B) AOM (x 40 magnifications); (C) Blastocystis (x 100 magnifications); (D) AOM + <i>Blastocystis</i> cyst (x 100 magnifications).</p
Representative histological Hematoxylin and Eosin (H and E) staining of villi of small intestine (x 40 magnifications).
<p>Control; (B) AOM; (C) <i>Blastocystis</i>; (D) AOM + <i>Blastocystis</i>.</p
Villous enterocytes contain <i>Blastocystis</i>-like organisms (Hematoxylin and Eosin staining).
<p>(A) x 40 magnifications; (B) x 200 magnifications; Lumen (C and D) (x 40 magnification).</p
Pearson’s correlation between the urinary biochemical variables in normal and <i>Blastocystis</i> infected group (control experiment for AOM + co-infection with <i>Blastocystis</i>).
<p>Pearson’s correlation between the urinary biochemical variables in normal and <i>Blastocystis</i> infected group (control experiment for AOM + co-infection with <i>Blastocystis</i>).</p
Comparison of (A) LHP, (B) AOPP, (C) H<sub>2</sub>O<sub>2</sub> and (D) FRAP levels in blood and urine samples of normal, <i>Blastocystis</i> infected, AOM-treated controls and rats treated with AOM + <i>Blastocystis</i> infection.
<p>Groups of six rats were inoculated with Blastocystis and injected with AOM simultaneously (co-infection). Data are given as mean SEM of six animals/group by Student’s t-test (SPSS version 13). ***P<0.001 is the comparison between columns of Blastocystis and normal as well as Blastocystis + AOM and AOM.</p