Correction: Association of Strongyloides stercoralis infection and type 2 diabetes mellitus in northeastern Thailand: Impact on diabetic complication-related renal biochemical parameters.

[This corrects the article DOI: 10.1371/journal.pone.0269080.].

Slight Changes in the Gut Microbiome in Early-stage Chronic Kidney Disease of Unknown Etiology.

Gut dysbiosis and changes in short-chain fatty acids (SCFAs) occur in end-stage chronic kidney disease (CKD); however, the degree of these changes in the gut microbiome and serum SCFA profiles in the early stages of CKD,| |particularly in| |CKD| |of unknown etiology (CKDu), is unclear. We herein investigated the gut microbiome and SCFA profiles of early-stage CKD patients (CKD stages 1-3) in a community in Khon Kaen Province, Thailand. Seventy-two parasite-free participants were distributed among a healthy control group (HC, n=18) and three patient groups (an underlying disease group [UD, n=18], early-stage CKD with underlying disease [CKD-UD, n=18], and early-stage CKD of unknown etiology, [CKDu, n=18]). Fecal DNA was individually extracted and pooled for groups of six individuals (three pools in each group) to examine the composition of the gut microbiome using next-generation sequencing. A SCFA ana-lysis was performed on serum samples from each individual using gas chromatography-mass spectrometry. The results revealed that microbial abundance differed between the healthy group and all patient groups (UD, CKD-UD, and CKDu). [Eubacterium]_coprostanoligenes_group was more abundant in the CKDu group than in the HC and CKD-UD groups. Furthermore, serum concentrations of acetate, a major SCFA component, were significantly lower in all patient groups than in the HC group. The present results indicate that minor changes in the gut microbiome and a significant decrease in serum acetate concentrations occur in early-stage CKDu, which may be important for the development of prevention strategies for CKD patients.

Opisthorchis viverrini infection induces metabolic disturbances in hamsters fed with high fat/high fructose diets: Implications for liver and kidney pathologies.

A combination of Opisthorchis viverrini infection and high fat/high fructose diets (HFa/HFr) intake is likely to enhance fatty liver and kidney pathologies. Here we investigated the combined effects of chronic O. viverrini infection and HFa/HFr intake on liver and kidney pathologies, metabolism, and gut microbiome in hamsters. Animals were infected with O. viverrini and fed with either standard chow (OV group) or HFa/HFr diet (OH group) and non-infected hamsters were fed with either standard chow (NC) or HFa/HFr diet (HF) for 8 months. The OH group exhibited dyslipidemia and the highest severity of fatty liver. Tubular damage, inflammatory cell infiltration, and tubular fibrosis were the most prominently observed in this group, supported by increased expression of KIM-1, HMGB-1, and MCP-1. Urinary 1H NMR metabolic profiles revealed that tauro-ß-muricholic acid level was increased in the OV and OH groups, whereas metabolites involved in the TCA cycle and gut microbiota-associated metabolites (phenylacetylglycine, trimethylamine, and trimethylamine-N-oxide) were lower in OV, HF and OH groups compared to the NC group. Gut microbial profiles of the OH group were also different from other groups. In conclusion, O. viverrini infection and HFa/HFr diet-induced disturbance of metabolites and gut microbiota associated with concurrent liver and kidney pathologies in hamsters.

Association of Strongyloides stercoralis infection and type 2 diabetes mellitus in northeastern Thailand: Impact on diabetic complication-related renal biochemical parameters.

BACKGROUND: Several studies have demonstrated that helminth infections provide a degree of protection against Type 2 diabetes mellitus (T2DM). However, the relationship between Strongyloides stercoralis infection and T2DM has scarcely been investigated and the protective effect of infection against development of diabetic complications is unclear. In this study, we aimed to investigate the relationship between S. stercoralis infection and T2DM in a rural area of Khon Kaen Province, Thailand. The impact of S. stercoralis infection on diabetic complication-related kidney function biochemical parameters and body-mass index (BMI) was also assessed. METHODOLOGY: Using a cross-sectional study design, S. stercoralis infection and T2DM assessments were conducted between October 2020 and May 2021. Associations between S. stercoralis infection, T2DM, and socioeconomic factors were analyzed using multivariable logistic regression analyses. Diabetic complication-related biochemical parameters relating largely to kidney function (estimated glomerular filtration rate (eGFR), urine albumin-to-creatinine ratio (UACR), serum creatinine, uric acid, alanine transaminase (ALT), and low-density lipoprotein cholesterol (LDL-C)) and BMI of participants with and without T2DM were compared between groups with or without S. stercoralis infection. RESULTS: One hundred and seven out of 704 individuals (15.20%) were positive for S. stercoralis, and 283 people were diagnosed with T2DM. Of those with T2DM, 11.31% (32/283) were infected with S. stercoralis and of those without T2DM, 17.82% (75/421) were infected with S. stercoralis. Multivariate analysis revealed that T2DM was inversely correlated with S. stercoralis infection (Adjusted OR = 0.49; 95% CI: 0.30, 0.78; p = 0.003), while male, increasing age, lower education level, and alcohol intake were positively associated with infection. Those infected with S. stercoralis had lower eGFR levels and higher ALT and UACR levels than those in the uninfected group. CONCLUSION: This finding indicates that S. stercoralis infection was inversely associated with T2DM in northeastern Thailand, but participants infected with S. stercoralis had lower eGFR levels and higher ALT and UACR levels. Infection with S. stercoralis might lead to worse complication-related renal biochemical parameters.

Opisthorchis viverrini Infection Induces Metabolic and Fecal Microbial Disturbances in Association with Liver and Kidney Pathologies in Hamsters.

Opisthorchis viverrini (Ov) infection causes hepatobiliary diseases and is a major risk factor for cholangiocarcinoma. While several omics approaches have been employed to understand the pathogenesis of opisthorchiasis, effects of Ov infection on the host systemic metabolism and fecal microbiota have not been fully explored. Here, we used a 1H NMR spectroscopy-based metabolic phenotyping approach to investigate Ov infection-induced metabolic disturbances at both the acute (1 month postinfection, 1 mpi) and chronic (4 mpi) stages in hamsters. A total of 22, 3, and 4 metabolites were found to be significantly different in the liver, serum, and urine, respectively, between Ov+ and Ov- groups. Elevated levels of hepatic amino acids and tricarboxylic acid (TCA)-cycle intermediates (fumarate and malate) were co-observed with liver injury in acute infection, whereas fibrosis-associated metabolites (e.g., glycine and glutamate) increased at the chronic infection stage. Lower levels of lipid signals ((CH2)n and CH2CH2CO) and higher levels of lysine and scyllo-inositol were observed in serum from Ov+ hamsters at 1 mpi compared to Ov- controls. Urinary levels of phenylacetylglycine (a host-bacterial cometabolite) and tauro-ß-muricholic acid were higher in the Ov+ group, which coexisted with hepatic and mild kidney fibrosis. Furthermore, Ov+ animals showed higher relative abundances of fecal Methanobrevibacter (Archaea), Akkermansia, and Burkholderia-Paraburkholderia compared to the noninfected controls. In conclusion, along with liver and kidney pathologies, O. viverrini infection resulted in hepatic and mild renal pathologies, disturbed hepatic amino acid metabolism and the TCA cycle, and induced changes in the fecal microbial composition and urinary host-microbial cometabolism. This study provides the initial step toward an understanding of local and systemic metabolic responses of the host to O. viverrini infection.

CagA+ Helicobacter pylori infection and N-nitrosodimethylamine administration induce cholangiocarcinoma development in hamsters.

BACKGROUND: Helicobacter pylori (HP) has been detected in the hepatobiliary tract of cholangiocarcinoma (CCA) patients in regions both endemic and non-endemic for Opisthorchis viverrini (OV) infection. However, whether H. pylori infection promotes CCA development remains unknown. We investigated CCA development in hamsters induced by a combination of infection with H. pylori and administration of N-nitrosodimethylamine (NDMA) and compared findings with those in an OV plus NDMA group. MATERIALS AND METHODS: Eighty-five hamsters were divided into four groups: (1) normal, (2) administered NDMA, (3) infected with cagA+ H. pylori and administered NDMA (HN group), and (4) infected with OV and administered NDMA (ON group). Animals were euthanized at 3 and 6 months post-infection. Histopathological changes of liver and the expression of markers associated with carcinogenesis were studied. RESULTS: At 3 months post-infection (p.i.), cholangitis and lymphoid follicles without tumor appearance were noted in the HN group, whereas extensive fibrosis was seen in members of the ON group, 10% of which had developed tumors. At 6 months p.i., 10% of hamsters administered NDMA alone had developed CCA, whereas in the HN and ON groups, 20% and 60% of hamsters, respectively, had developed CCA. Cytokeratin-19 (CK19) expression was observed in the CCA tissues of both the HN and the ON groups, confirming the bile duct origin of the CCA cells. CCA development in the HN group might be inflammation-mediated, as suggested by overexpression of HMGB1, PCNA, IL-8, and 8-OxodG in CCA tissues. CONCLUSION: cagA+ H. pylori infection and carcinogen intake can induce CCA development with slow progression.

Phylogeography and demographic history of Thai Pediculus humanus capitis (Phthiraptera: Pediculidae) revealed by mitochondrial DNA sequences.

Pediculus humanus (human louse) is a hematophagous insect that feeds on human blood. It is distributed worldwide. Understanding phylogeography and population-genetic structure of the human louse will illuminate the evolution of this insect and the dynamics of how resistance alleles might spread in the landscape. In this work, we used mitochondrial (cox1 and cytb genes) sequences of the human louse to investigate genetic diversity, population-genetic structure and demographic history of the louse in Thailand. Human lice in Thailand belonged to mitochondrial clades A and C. Most genetic variation was attributed to intra-region 65.71% within provinces for clade A and 68.92% for clade C, while inter-region level was 34.40% among provinces within regions for clade A and 20.09% for clade C. Neutrality and other indices suggested that louse populations from clades A and C in Thailand have experienced a population expansion. But head lice from Khon Kaen Province in clade C demonstrated a significant recent population bottleneck or natural selective pressure with constant population size. Head lice in Thailand showed varying degrees of low to high genetic differentiation at the level of province with many populations being genetically distinct from each other among regions and within the same region. Knowledge of the clades present in Thailand and that gene flow occurs between regions will assist in developing appropriate strategies for management of head lice at the local level in the country.

Profiling of Bile Microbiome Identifies District Microbial Population between Choledocholithiasis and Cholangiocarcinoma Patients.

OBJECTIVE: Choledocholithiasis (CDL), a potential risk for cholangiocarcinoma (CCA) development, is often a consequence of bacterial infection. Thus, the microbial population that contributes to CDL might also be involved in CCA development. We compared the microbiome in bile fluid of CDL patients and CCA patients. METHODS: Bile samples were collected from CDL (n = 30) and CCA (n =30) patients. Microbial profiling was performed individually by the sequencing of V3-V4 regions of the 16S rRNA gene. RESULTS: Enterobacter, Pseudomonas, and Stenotrophomonas species were much more abundant in bile samples from CCA compared to CDL (p.

A combination of monosodium glutamate and high-fat and high-fructose diets increases the risk of kidney injury, gut dysbiosis and host-microbial co-metabolism.

Consumption of either monosodium glutamate (MSG) or high-fat and high-fructose (HFF) diets changes the gut microbiome and hence contributes to development of several diseases. In this study, with an emphasis on kidney injury, hamsters were divided into 4 groups as follows: (1) hamsters fed with standard diet (control); (2) hamsters fed with standard diet and MSG in drinking water (MSG); (3) hamsters fed with high-fat and high-fructose diets (HFF), and (4) animals fed MSG+HFF. After 8 months, the animals were used for the study. Despite showing normal kidney function, hamsters fed with MSG+HFF exhibited signs of kidney damage as demonstrated by the highest expression levels of high-mobility group box-1 and kidney injury molecule-1 in kidney tissues, while slight changes of histopathological features in H&E-stained sections and normal levels of creatinine were observed, indicating possible early stages of kidney injury. Sequencing of the microbial 16S rRNA gene revealed that animals fed with the MSG+HFF diet had a higher ratio of gut Firmicutes/Bacteroidetes along with marked changes in abundance and diversity of gut microbiome compared to hamsters fed with MSG or HFF alone. In addition, 1H Nuclear magnetic resonance spectroscopy showed an elevation of urine p-cresol sulfate levels in the MSG+HFF group. These results indicate that consumption of both MSG and HFF increases the risk of kidney injury, induces gut dysbiosis and an increase in the amount of p-cresol sulfate in hamsters.

Improved agar plate culture conditions for diagnosis of Strongyloides stercoralis.

Strongyloides stercoralis infection causes gastrointestinal symptoms and can lead to severe disease in immunocompromised hosts. Live larvae are passed in feces, encouraging the common use of diagnosis by cultivation methods including agar plate culture (APC), the gold-standard technique. Nevertheless, APC has limitations, especially since there can be considerable day-to-day fluctuations in numbers of larvae produced. Herein, we collected stool samples from heavily infected subjects with strongyloidiasis in Khon Kaen Province, Thailand, to evaluate modifications (temperature, pH, nutrition source and salinity) to APC conditions to maximize the number of S. stercoralis worms counted. Best results were obtained using a modified APC with the following conditions: pH 6.0, 0.5% of NaCl, addition of yeast extract for nutrition and incubation at 29-30 °C. This modified APC was more sensitive for detection of S. stercoralis than was standard APC or the formalin-ethyl acetate concentration technique. In brief, this finding suggests that a modification of standard APC conditions increases the counts of S. stercoralis.

Correction: Fecal microbiota dysbiosis in macaques and humans within a shared environment.

[This corrects the article DOI: 10.1371/journal.pone.0210679.].

Fecal microbiota dysbiosis in macaques and humans within a shared environment.

Traditional zoonotic disease research focuses on detection of recognized pathogens and may miss opportunities to understand broader microbial transmission dynamics between humans, animals, and the environment. We studied human-macaque microbiome overlap in Kosum Phisai District, Maha Sarakham Province, Thailand, where a growing population of long-tailed macaques (Macaca fascicularis) in Kosumpee Forest Park interact with humans from an adjacent village. We surveyed workers in or near the park with elevated exposure to macaques to characterize tasks resulting in exposure to macaque feces in addition to dietary and lifestyle factors that influence gut microbiome composition. Fecal samples were collected from 12 exposed workers and 6 controls without macaque exposure, as well as 8 macaques from Kosumpee Forest Park and 4 from an isolated forest patch with minimal human contact. The V4 region of the 16S rRNA gene from fecal sample extracted DNA was amplified and sequenced using Illumina MiSeq to characterize the microbial community. A permuted betadisper test on the weighted UniFrac distances revealed significant differences in the dispersion patterns of gut microbiota from exposed and control macaques (p = 0.03). The high variance in gut microbiota composition of macaques in contact with humans has potential implications for gut microbiome stability and susceptibility to disease, described by the Anna Karenina principle (AKP). Human samples had homogenous variance in beta diversity but different spatial medians between groups (p = 0.02), indicating a shift in microbial composition that may be explained by fundamental lifestyle differences between the groups unrelated to exposure status. SourceTracker was used to estimate the percent of gut taxa in exposed humans that was contributed by macaques. While one worker showed evidence of elevated contribution, the overall trend was not significant. Task observations among workers revealed opportunities to employ protective measures or training to reduce exposure to occupational hazards. These results suggest the potential for hygiene measures to mitigate negative aspects of contact between humans and macaques in order to optimize the health of both populations.

Effect of a health education program on reduction of pediculosis in school girls at Amphoe Muang, Khon Kaen Province, Thailand.

BACKGROUND: Pediculosis caused by head lice (Pediculus humanus capitis) infestation is still an important health problem in schoolchildren, especially girls, worldwide, including in Thailand. Although pediculicidal agents effectively kill head lice, the re-infestation rate is still high. Thus, prevention is an important strategy for any sustainable control program. We aimed to develop and evaluate the efficacy of a health education program for increasing knowledge, changing attitudes and promoting preventive practices to reduce prevalence of pediculosis among school girls in Amphoe Muang, Khon Kaen, northeastern Thailand. METHODOLOGY: Six schools were selected using multistage simple randomization and were allocated into intervention or control groups. A total of 267 girls was enrolled from these schools. A "knowledge, attitude and practice" (KAP) questionnaire, consent forms and health education materials were constructed and tested by experts and in one pilot school before the main investigation. Baseline prevalence of adult lice and nits was determined. The health education package was given only to the intervention group. The KAP questionnaire was re-evaluated at two months after intervention. RESULTS: At baseline, the prevalence and intensity of head lice infestation, and the KAP scores did not differ significantly between the two groups. After re-evaluation at two months, the KAP score was significantly greater in the intervention group. A significant decrease of the infestation rate from 59% to 44% was observed in the intervention group, whereas infestation increased in the control group (from 56% to 65%). The incidence of new cases in the intervention group (6.14%) was lower than in the control group (12.62%). CONCLUSION: These findings indicated that the newly-established health education package is an effective tool for increasing KAP and reducing head lice infestation in school girls. Efforts to combat pediculosis in schoolchildren elsewhere may consider including this, or a similar, health education package in their programs.

Melatonin suppresses eosinophils and Th17 cells in hamsters treated with a combination of human liver fluke infection and a chemical carcinogen.

BACKGROUND: The combination of Opisthorchis viverrini (OV) infection and chemical carcinogen induces cholangiocarcinoma (CCA) in hamsters via inflammation-mediated mechanisms. Thus, suppression of inflammatory cells at the initial stages of CCA development would be of benefit. We aimed to investigate whether IL-17-producing CD4+ T cells (Th17) and CD4+ Foxp3+ T cells (Treg) are involved in the early stages of CCA genesis and can be targeted for suppression by melatonin. METHODS: Inflammation, an initial stage of CCA development, was induced in hamsters by a combination of O. viverrini infection and N-nitrosodimethylamine (NDMA) administration. Melatonin (50mg/kg) was additionally administered to one group for the 30days of the experiment. Liver tissue-resident T cells were investigated using immunostaining, western blotting, and real-time PCR. RESULTS: OV+NDMA-induced CCA tissues showed significantly higher numbers of inflammatory cells, especially eosinophils, bile duct proliferation and IL-17+ cell infiltration compared to normal livers. Expression of Foxp3 was localized in the bile duct epithelial cells, and especially in the bile duct hyperplasia. Accumulation of CD4+ and IL-17+ cells and intense staining of the Foxp3+ marker were consistent with their protein levels. Infiltration of IL-17+ inflammatory cells and Foxp3+ cells, as well as increases in their transcription expression levels, were significantly lower in the melatonin-treated group. In contrast, increased CD4+ cell infiltration and TNF-α expression were also observed through melatonin treatment. CONCLUSION: Melatonin exerts an immunomodulatory effect, suppressing eosinophils and Th17 cells and expression of Foxp3, but enhancing CD4+ cells and TNF-α. This suggests that melatonin may be used for CCA chemoprevention.

Coinfection with Helicobacter pylori and Opisthorchis viverrini Enhances the Severity of Hepatobiliary Abnormalities in Hamsters.

Persistent infection with Opisthorchis viverrini causes hepatobiliary abnormalities, predisposing infected individuals to cholangiocarcinoma (CCA). In addition, Helicobacter pylori is highly prevalent in most countries and is a possible risk factor for CCA; however, its role in enhancing hepatobiliary abnormality is unclear. Here, we investigated the effects of coinfection with H. pylori and O. viverrini on hepatobiliary abnormality. Hamsters were divided into four groups: (i) normal, (ii) H. pylori infected (HP), (iii) O. viverrini infected (OV), and (iv) O. viverrini and H. pylori infected (OV+HP). At 6 months postinfection, PCR and immunohistochemistry were used to test for the presence of H. pylori in the stomach, gallbladder, and liver. In the liver, H. pylori was detected in the following order: OV+HP, 5 of 8 (62.5%); HP, 2 of 5 (40%); OV, 2 of 8 (25%). H. pylori was not detected in normal (control) liver tissues. Coinfection induced the most severe hepatobiliary abnormalities, including periductal fibrosis, cholangitis, and bile duct hyperplasia, leading to a significantly decreased survival rate of experimental animals. The greatest thickness of periductal fibrosis was associated with a significant increase in fibrogenesis markers (expression of alpha smooth muscle actin and transforming growth factor beta). Quantitative reverse transcription-PCR revealed that the highest expression levels of genes for proinflammatory cytokines (interleukin-1 [IL-1], IL-6, and tumor necrosis factor alpha) were also observed in the OV+HP group. These results suggest that coinfection with H. pylori and O. viverrini increased the severity of hepatobiliary abnormalities to a greater extent than either single infection did.

Chronic Opisthorchis viverrini Infection Changes the Liver Microbiome and Promotes Helicobacter Growth.

Adults of Opisthorchis viverrini reside in the biliary system, inducing inflammation of bile ducts and cholangitis, leading to hepatobiliary disease (HBD) including cholangiocarcinoma. O. viverrini infection also has major implications for the bacterial community in bile ducts and liver. To investigate this in chronic O. viverrini infection (≥ 8 months p.i.), bacterial genomic DNA from livers of hamsters and from worms was investigated using culture techniques, PCR for Helicobacter spp. and high-throughput next-generation sequencing targeting the V3-V4 hypervariable regions of prokaryotic 16S rRNA gene. Of a total of 855,046 DNA sequence reads, 417,953 were useable after filtering. Metagenomic analyses assigned these to 93 operational taxonomic units (OTUs) consisting of 80 OTUs of bacteria, including 6 phyla and 42 genera. In the chronic O. viverrini-infected group, bacterial community composition and diversity were significantly increased compared to controls. Sequences of Fusobacterium spp. were the most common (13.81%), followed by Streptococcus luteciae (10.76%), Escherichia coli (10.18%), and Bifidobacterium spp. (0.58%). In addition, Helicobacter pylori (0.17% of sequences) was also identified in the liver of chronic O. viverrini infections, but not in normal liver. The presence of H. pylori was confirmed by PCR and by use of an antibody against bacterial antigen, supporting the metagenomics data. The identities of bacteria cultured for enrichment suggested that chronic O. viverrini infection changes the liver microbiome and promotes Helicobacter spp. growth. There may be synergy between O. viverrini and the liver microbiome in enhancing immune response-mediated hepatobiliary diseases.