Intestinal parasites infecting captive non-human primates in Italy

Non-human primates (NHPs) living in captive conditions are susceptible to intestinal parasites that can contribute to mortality and morbidity, and cause zoonotic infections. Thus, parasite surveys on NHP populations under human care are relevant as part of the evaluation of NHPs welfare and in the zoonotic disease risk assessment, as well as in the exploration of parasite transmission pathways, according to the One-Health concept. This study aimed to identify intestinal parasites infecting NHPs living in two wildlife recovery centers and in a zoological garden, in Italy. Ninety-three fecal samples from Macaca tonkeana, Macaca fascicularis, Sapajus apella, Chlorocebus aethiops, Macaca fuscata, Macaca sylvanus, and Cebus capucinus were collected at Piano dell'Abatino Park (Lazio), and fecal smears and flotation were performed in order to identify parasites according to morphological keys. Additionally, one carcass of M. fuscata from the Bioparco Zoological Garden of Rome (Lazio) and one of M. fascicularis from the Center for the Recovery of Exotic and Maremma Wild Animals (Tuscany) were necropsied and intestinal adult nematodes were collected and characterized at morphological and molecular level, using the mitochondrial cox1 and rrnL markers. Protozoans (Entamoeba coli, Iodamoeba bütschlii, Dientamoeba fragilis-like, Giardia sp.), chromists (Balantidium/Buxtonella sp.) and nematodes (Capillaria sp., Trichuris sp., strongyliform larvae and Oesophagostomum sp.) were found through fecal smears and flotation. The collected adult nematodes from dead NHPs were morphologically identified as whipworms (genus Trichuris). Phylogenetic analyses grouped Trichuris specimens into the Trichuris trichiura complex of species, with specimens from M. fuscata clustering into a host-specific branch, and whipworms from M. fascicularis clustering within a clade formed by Trichuris infecting several primate species, including humans. The results here collected revealed the presence of potentially zoonotic parasites circulating in captive primates in Italy, providing useful information for the formulation of management and care plans for captive NHPs, and for the elaboration of safety measures for visitors and animal keepers.

Human alveolar echinococcosis in Slovakia: Epidemiology and genetic diversity of Echinococcus multilocularis, 2000-2023

Human alveolar echinococcosis (AE) is a serious parasitic disease caused by larval stages of Echinococcus multilocularis. Between January 2000 and October 2023, 137 AE cases were confirmed in Slovakia. The average annual incidence increased from 0.031 per 100,000 inhabitants between 2000 and 2011, to an average of 0.187 since 2012, i.e. about six times. Among patients, 45.3% were men and 54.7% were women; the mean age at the time of diagnosis was 52.8 years. Most cases were diagnosed in the age groups 51-60 years and 61-70 years (33 cases each), and eight patients fell into the age category ≤ 20 years. To better recognize the gene diversity in clinical samples, metacestodes from 21 patients collected between 2013 and 2021 were subjected to DNA sequencing of four mitochondrial genes. Using concatenated sequences of cob (603 bp), nad2 (882 bp) and cox1 (789 bp) gene fragments, 14 isolates (66.7%) were assigned to the European E5 profile of E. multilocularis, two isolates (9.5%) to the E5a subtype, four isolates (19%) to the E4 profile, and one isolate (4.8%) to haplogroup E1/E2. The E5-type profiles and E4 profiles were distributed throughout the country, whereas the E1/E2 profile was found in the patient from western Slovakia. According to the data obtained and GenBank sequences, the E5-type dispersal is so far limited to central-eastern Europe and the variant seems to be indigenous to that region. The admixture with the haplotypes E4 and E1/E2 could have taken place from a historical endemic focus during the fox expansion in the last decades. By employing the nad1 fragment, a typical European haplotype was observed in all 21 resolved Slovak samples. The acceleration in the AE incidence in the last decade suggests the emergence of the disease and the need for further research on human and animal isolates.

A Case of Gastroallergic and Intestinal Anisakiasis in Italy: Diagnosis Based on Double Endoscopy and Molecular Identification

Nematodes of the genus Anisakis (Rhabditida, Anisakidae) are zoonotic fish-borne parasites and cause anisakiasis, a disease with mild to severe acute or chronic gastrointestinal and allergic symptoms and signs. Anisakiasis can potentially lead to misdiagnosis or delay in diagnosis, and it has been suggested as a risk factor for gastrointestinal tumors. Here, we describe a case report of a 25-year-old woman who presented with gastrointestinal (abdominal pain, nausea, diarrhea) and allergic (diffuse skin rash) symptoms and reported ingestion of raw fish contaminated by worms. Gastro and colon endoscopy allowed the visualization and removal of nematodes and collection of bioptic tissue from ulcers and polyps. The removed nematodes were molecularly identified as Anisakis pegreffii. The patient was treated with chlorphenamine maleate, betamethasone, omeprazole, paracetamol, albendazole. We conclude that an upper endoscopy matched with a colonoscopy and molecular characterization of the pathogen yields the most reliable diagnosis and treatment for human anisakiasis, enabling the complete removal of the larvae and preventing chronic inflammation and damage.

Prevalence and Molecular Characterisation of Blastocystis sp. Infecting Free-Ranging Primates in Colombia

Infection with Blastocystis sp. has been reported in free-living and captive non-human primates (NHPs); however, surveys on Blastocystis sp. from north-western South America are scarce. This study aimed to identify Blastocystis sp. in free-ranging NHPs living in Colombia. A total of 212 faecal samples were collected from Ateles hybridus, Cebus versicolor, Alouatta seniculus, Aotus griseimembra, Sapajus apella, and Saimiri cassiquiarensis. Smears and flotation were used for morphological identification. For samples microscopically classified as positive for Blastocystis sp., we used conventional PCR to amplify and sequence two regions of the SSU rRNA gene and used Maximum Likelihood methods and Median Joining Network analyses for phylogenetic analyses. Via microscopy, 64 samples were Blastocystis sp. positive. Through molecular analyses, 18 sequences of Blastocystis sp. subtype 8 (ST8) were obtained. Strain and allele assignment together with a comparative phylogenetic approach confirmed that the sequences were ST8. Alleles 21, 156, and 157 were detected. Median Joining network analyses showed one highly frequent haplotype shared by specimens from Colombia and Peru and close relationships between haplotypes circulating in NHPs from Colombia, Ecuador, Brazil, and Mexico. This survey could support the elaboration of a more accurate epidemiological picture of the Blastocystis sp. infecting NHPs.

Identification of Contracaecum rudolphii (Nematoda: Anisakidae) in Great Cormorants Phalacrocorax carbo sinensis (Blumenbach, 1978) from Southern Italy

In this study, four dead great cormorant Phalacrocorax carbo sinensis (Blumenbach, 1978) specimens, collected from the coasts and lakes of Southern Italy, were examined by necropsy for the detection of Contraceacum sp. The adults and larvae found were subjected to morphological analysis and molecular identification by PCR-RFLP. A total of 181 Contracaecum specimens were detected in all of the four great cormorants examined (prevalence = 100%), showing an intensity of infestation between nine and ninety-two. A co-infestation by adult and larval forms of Contracaecum rudolphii was found only in one of the great cormorants examined. Following molecular investigations, 48 specimens of C. rudolphii A and 38 specimens of C. rudolphii B were detected, revealing co-infestation solely for the great cormorant from Leporano Bay (Southern Italy). Our results showed an opposite ratio between C. rudolphii A and C. rudolphii B in Pantelleria and in Salso Lake (Southern Italy) compared to what was reported in the literature, probably due to migratory stopovers and the ecology of the infested fish species, confirming the role of Contracaecum nematodes as ecological tags of their hosts.

Special considerations for studies of extracellular vesicles from parasitic helminths: A community-led roadmap to increase rigour and reproducibility

Over the last decade, research interest in defining how extracellular vesicles (EVs) shape cross-species communication has grown rapidly. Parasitic helminths, worm species found in the phyla Nematoda and Platyhelminthes, are well-recognised manipulators of host immune function and physiology. Emerging evidence supports a role for helminth-derived EVs in these processes and highlights EVs as an important participant in cross-phylum communication. While the mammalian EV field is guided by a community-agreed framework for studying EVs derived from model organisms or cell systems [e.g., Minimal Information for Studies of Extracellular Vesicles (MISEV)], the helminth community requires a supplementary set of principles due to the additional challenges that accompany working with such divergent organisms. These challenges include, but are not limited to, generating sufficient quantities of EVs for descriptive or functional studies, defining pan-helminth EV markers, genetically modifying these organisms, and identifying rigorous methodologies for in vitro and in vivo studies. Here, we outline best practices for those investigating the biology of helminth-derived EVs to complement the MISEV guidelines. We summarise community-agreed standards for studying EVs derived from this broad set of non-model organisms, raise awareness of issues associated with helminth EVs and provide future perspectives for how progress in the field will be achieved.

Rat and fish peripheral blood leukocytes respond distinctively to Anisakis pegreffii (Nematoda, Anisakidae) crude extract

Infective third-stage larvae (L3) of the marine nematode Anisakis pegreffii cause inflammation and clinical symptoms in humans, their accidental host, that subside and self-resolve in a couple of weeks after L3 die. To characterise the differences in an early immune response of a marine vs. terrestrial host, we stimulated peripheral blood leukocytes (PBLs) of fish (paratenic host) and rat (accidental, human-model host) with A. pegreffii crude extract and analysed PBL transcriptomes 1 and 12 h post-stimulation. Fish and rat PBLs differentially expressed 712 and 493 transcripts, respectively, between 1 and 12 h post-stimulation (false discovery rate, FDR <0.001, logFC >2). While there was a difference in the highest upregulated transcripts between two time-points, the same Gene Ontologies, biological processes (intracellular signal transduction, DNA-dependent transcription, and DNA-regulated regulation of transcription), and molecular functions (ATP and metal ion binding) were enriched in the two hosts, showing an incrementing dynamic between 1 and 12 h. This suggests that the two distinct hosts employ qualitatively different transcript cascades only to achieve the same effect, at least during an early innate immunity response. Activation of later immunity elements and/or a combination of other host's intrinsic conditions may contribute to the death of L3 in the terrestrial host.

Neglected Diseases—Parasitic Infections among Slovakian Children from Different Populations and Genotypes of Giardia duodenalis

Children are most prone to parasitic infections. The objectives of the study were to examine the occurrence of parasitic infections in children from different populations and to perform molecular characterization of human Giardia duodenalis isolates. We examined 631 stool samples from Roma and non-Roma children for the presence of parasitic developmental stages. Samples were collected from three eastern Slovakia districts. The ages of the children ranged from 1 months to 17 years. Subsequently, the molecular characterization of human G. duodenalis isolates by PCR detected triosephosphate isomerase (tpi) and beta-giardin (bg) genes was performed. The overall prevalence of parasitic infection was 19.8%. Ascaris lumbricoides eggs were the most frequent, with an occurrence of about 13.8%. G. duodenalis cysts were present in 6.3% of samples. G. duodenalis isolates obtained from 13 children were subjected to DNA sequencing with tpi and bg genes. Five isolates were categorized as bearing subassemblage BIII, the three isolates as subassemblage BIV, one person was infected with a mixture of subassemblages BIII and BIV, four children had subassemblage AII, and one isolate revealed a structure corresponding with subassemblage AI. Our work is proof that poverty and poor hygiene contribute the most to public health problems associated with neglected parasitic diseases.

Parasites of Free-Ranging and Captive American Primates: A Systematic Review

The diversity, spread, and evolution of parasites in non-human primates (NHPs) is a relevant issue for human public health as well as for NHPs conservation. Although previous reviews have recorded information on parasites in NHPs (Platyrrhines) in the Americas, the increasing number of recent studies has made these inventories far from complete. Here, we summarize information about parasites recently reported in Platyrrhines, attempting to build on earlier reviews and identify information gaps. A systematic literature search was conducted in PubMed, ISI Web of Science, and Latin American and Caribbean Health Sciences Literature (LILACS), and following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Ninety-three studies were included after the screening process. Records for 20 genera of NHPs, including 90 species were found. Most of the studies were conducted on captive individuals (54.1%), and morphological approaches were the most used for parasite identification. The most commonly collected biological samples were blood and stool, and Protozoa was the most frequent parasite group found. There is still scarce (if any) information on the parasites associated to several Platyrrhine species, especially for free-ranging populations. The use of molecular identification methods can provide important contributions to the field of NHPs parasitology in the near future. Finally, the identification of parasites in NHPs populations will continue to provide relevant information in the context of pervasive habitat loss and fragmentation that should influence both human public health and wildlife conservation strategies.

Ascariasis in a 75-year-old man with small bowel volvulus: a case report

Background

Ascaris lumbricoides and Ascaris suum are the most common soil-transmitted helminths of humans and pigs, respectively. The zoonotic potential of A. suum has been a matter of debate for decades. This study was aimed to present a case of human ascariasis caused by A. suum in southern Italy.

Case presentation

A 75-year-old man presented to the department of surgery in Avellino (southern Italy) complaining of abdominal pain and vomiting. Physical examination revealed bloating and abdominal tenderness. A computed tomography scan showed air-fluid levels and small bowel distension. During exploratory laparotomy a small bowel volvulus with mesenteritis was evident and surprisingly an intraluminal worm was detected. The worm was removed with a small enterotomy and identified as an adult female of A. suum based on morphological and molecular analysis. Faecal examination revealed the presence of unfertilized Ascaris eggs with an intensity of 16 eggs per gram (EPG) of faeces. The patient was treated with mebendanzole 100 mg twice a day for 3 days. The post-operative course was regular with re-alimentation after 3 days and discharge after 12 days.

Conclusions

This report shows as A. suum can function as a relevant agent of human zoonosis. Therefore, in patients with bowel obstruction with no evident aetiology a helminthic infestation should be considered for an accurate diagnosis, especially in patients living in rural areas.

An unpleasant souvenir: Endoscopic finding of Trichuris trichiura (Nematoda: Trichuridae)

Whipworms are responsible for up to 500 million cases of trichuriasis worldwide, with higher endemicity in tropical and sub-tropical countries. In non-endemic countries, trichuriasis can be accidentally diagnosed upon colonoscopy, often in the presence of negative microscopy. Here, we describe an incidental diagnosis of trichuriasis in an HIV patient residing in a non-endemic area (i.e., Turin, Italy), six months after his return from Antigua. The species-level diagnosis was made thanks to PCR-based molecular identification of Trichuris sp. following optical microscopy detection. Overall, this case highlights the importance of improving parasitic diseases diagnosis through cutting-edge clinical and laboratory diagnostic tools alongside advanced training of specialists in the area of parasitology.

Advances in Omic Studies Drive Discoveries in the Biology of Anisakid Nematodes

Advancements in technologies employed in high-throughput next-generation sequencing (NGS) methods are supporting the spread of studies that, combined with advances in computational biology and bioinformatics, have greatly accelerated discoveries within basic and biomedical research for many parasitic diseases. Here, we review the most updated "omic" studies performed on anisakid nematodes, a family of marine parasites that are causative agents of the fish-borne zoonosis known as anisakiasis or anisakidosis. Few deposited data on Anisakis genomes are so far available, and this still hinders the deep and highly accurate characterization of biological aspects of interest, even as several transcriptomic and proteomic studies are becoming available. These have been aimed at discovering and characterizing molecules specific to peculiar developmental parasitic stages or tissues, as well as transcripts with pathogenic potential as toxins and allergens, with a broad relevance for a better understanding of host-pathogen relationships and for the development of reliable diagnostic tools.

Sarcoptic Mange in Wild Caprinae of the Alps: Could Pathology Help in Filling the Gaps in Knowledge?

Sarcoptic mange represents the most severe disease for wild Caprinae individuals and populations in Europe, raising concerns for both conservation and management of these ungulates. To date, this disease has been investigated in different wild caprine species and under many different perspectives including diagnostics, epidemiology, impact on the host populations, and genetics of both hosts and parasite, with the aim to disentangle the host-Sarcoptes scabiei relationship. Notwithstanding, uncertainty remains and basic questions still need an answer. Among these are the effect of immune responses on mange severity at an individual level, the main drivers in host-parasite interactions for different clinical outcomes, and the role of the immune response in determining the shift from epidemic to endemic cycle. A deeper approach to the pathology of this disease seems therefore advisable, all the more reason considering that immune response to S. scabiei in wild Caprinae, generally classified as a hypersensitivity, remains poorly understood. In this paper, we reviewed the pathological features associated to sarcoptic mange in wildlife, exploring different kinds of hypersensitivity and outcomes, with the objective of highlighting the major drivers in the different responses to this disease at an individual level and proposing some key topics for future research, with a particular attention to Alps-dwelling wild caprines.

Comparative Transcriptomics Reveals Clues for Differences in Pathogenicity between Hysterothylacium aduncum, Anisakis simplex sensu stricto and Anisakis pegreffii

Ascaridoid nematodes are widespread in marine fishes. Despite their major socioeconomic importance, mechanisms associated to the fish-borne zoonotic disease anisakiasis are still obscure. RNA-Seq and de-novo assembly were herein applied to RNA extracted from larvae and dissected pharynx of Hysterothylacium aduncum (HA), a non-pathogenic nematode. Assembled transcripts in HA were annotated and compared to the transcriptomes of the zoonotic species Anisakis simplex sensu stricto (AS) and Anisakis pegreffii (AP). Approximately 60,000,000 single-end reads were generated for HA, AS and AP. Transcripts in HA encoded for 30,254 putative peptides while AS and AP encoded for 20,574 and 20,840 putative peptides, respectively. Differential gene expression analyses yielded 471, 612 and 526 transcripts up regulated in the pharynx of HA, AS and AP. The transcriptomes of larvae and pharynx of HA were enriched in transcripts encoding collagen, peptidases, ribosomal proteins and in heat-shock motifs. Transcripts encoding proteolytic enzymes, anesthetics, inhibitors of primary hemostasis and virulence factors, anticoagulants and immunomodulatory peptides were up-regulated in AS and AP pharynx. This study represents the first transcriptomic characterization of a marine parasitic nematode commonly recovered in fish and probably of negligible concern for public health.

Relationship of Leishmania RNA Virus (LRV) and treatment failure in clinical isolates of Leishmania major

OBJECTIVE

Leishmaniasis is caused by different Leishmania spp. Treatment failure (TF) of cutaneous leishmaniasis (CL) is a serious issue that may be due to various reasons, previous studies suggested Leishmania RNA virus (LRV) as a potential cause of TF. Two variant groups of LRV1 and LRV2 are reported. In this study, the presence of LRV1/LRV2 was compared in TF with treatment response (TR) isolates of L. major. Clinical isolates of 15 TF and 15 TR were collected from CL patients referred to the Health Centers of Isfahan. Genomic DNA was extracted to identify Leishmania spp. using ITS1-PCR-RFLP. Identification of LRV1/LRV2 was performed using SYBR Green Real-Time PCR. The statistical analysis to test relationship between the treatment response with Glucantime and the presence of LRV were performed using SPSS 16.0 with Fisher's Exact test. P value of less than 0.05 was considered significant.

RESULTS

ITS1-PCR-RFLP results showed that every isolate was identified as L. major. The results showed no LRV1 in any of the samples but 7 TR isolates and 2 TF isolates showed positive for LRV2. Statistical analysis showed no significant difference between the presence of LRV2 and response to Glucantime (p-value = 0.1086). Therefore, other mechanisms might be responsible for TF.

Molecular characterization of Trichuris spp. from captive animals based on mitochondrial markers

Monoxenous parasites may easily infect animals in captivity, and nematodes belonging to the genus Trichuris are commonly reported in zoological gardens worldwide. Infections in captive animals should be accurately monitored and the characterization of pathogens is highly advisable, as a tool to infer possible routes of intra- and interspecific transmission pathways and to assess the related zoonotic potential. Whipworms are usually identified on the basis of few morphological features of adults males and eggs and by an host-affiliation criterion. Given the strong morphological convergence of adaptive traits and the possible occurrence of hybridization and/or cross-infections events, the use of molecular methods is of great utility. Here, we analysed two partial mitochondrial loci, the cytochrome c oxidase I and the cytochrome b regions, in Trichuris spp. infecting four animal species hosted in the Bioparco Zoological Garden of Rome. Results from molecular systematics, compared to previous data, suggested that the five Trichuris taxa recovered were well separated, showing a significant degree of host affiliation (herbivorous, primates/swine and rodents/canids). The screw horn antelopes and the camels were infected with two variants of Trichuris ovis; Trichuris sp. similar to those observed in rodents from South America was infecting the Patagonian maras. Moreover, Trichuris from the ring-tailed lemur showed a great similarity to Trichuris infecting the Japanese macaque previously analysed from the same zoological garden, and clustering together with Trichuris trichiura, posing a potential zoonotic threat for visitors and workers.

On the geographic genetic variants of the cestode Echinococcus multilocularis with reference to the original descriptions from Bowles et al. (1992) and Bowles and McManus (1993), and their use

Alveolar echinococcosis, caused by the larval stages of the tapeworm Echinococcus multilocularis (Leuckart, 1863), is of increasing concern in the northern hemisphere. Most cases of alveolar echinococcosis (excluding Alaska) appear to be linked with European and Asian genotypes that highlight the need for a more precise delimiting of their actual distribution and tracing historical episodes of their translocations and introductions into new areas. We have herein summarized previous available research studies, which mentioned firstly described geographic M1/M2 variants of E. multilocularis using molecular tools (established by sequencing of mitochondrial genes cox1, 366 bp and nad1, 471 bp), in an attempt to consolidate their correct affiliations with the geographic origin in sense of the original description from the early 1990´s. Since 2009, inverted designations (M1 named as M2 and vice versa) are being prevailing in research literature (we found ten erroneous vs. three correct classifications) that might bias genetic interpretation of comparative data in specific cases. When comparing M1/M2 profiles to those obtained from mitochondrial evidences over the last decades, the phylogenetic analysis revealed that the M1 strain (originally described from China, Alaska, North America) grouped with the Asian clade of E. multilocularis more recently established, whereas the M2 strain (described from the German vole) had a specific structure, in cox1 clustering with the North American clade. It is presumed that events of intercontinental expansion and isolation covering glacial and interglacial periods during the late Pleistocene have likely accounted for the transmission of this discrete genotype from Beringia into endemic area of western and central Europe via circumpolar movements of foxes.

Occurrence of Anisakis and Hysterothylacium Nematodes in Atlantic Chub Mackerels from Libyan Coasts

The occurrence of zoonotic parasitic nematodes in Atlantic chub mackerels (Scomber colias syn. Scomber japonicus) from Libyan waters was investigated, using epizootiological estimations and molecular specific characterization of larvae. Nematodes belonging to Anisakis spp., the main etiological agent of anisakiasis in Mediterranean waters, and to Hysterothylacium spp. so far considered not pathogenic to humans, were detected. Prevalence values were generally high in visceral cavities (over 40 % for both parasites) while were low for Anisakis (around 1 %) and null for Hysterothylacium in muscles. Moreover, the level of infections was associated with seasons, a feature potentially useful to plan fishing captures and to elaborate risk mitigation strategies for anisakiasis. Species molecular identification performed on a subsample described the presence of Hysterothylacium aduncum as the predominant species, along with Anisakis pegreffii and the hybrids (A. pegreffii and A. simplex sensu stricto), thus posing a concrete zoonotic risk following the consumption of such fish species as a raw preparation.

Anisakiasis in Italy: Analysis of hospital discharge records in the years 2005-2015

Background

Anisakiasis is a fish-borne zoonosis caused by the ingestion of marine food infected with Anisakis third-stage larvae, widespread marine parasitic nematodes. Gastrointestinal and/or allergic clinical signs and symptoms are not specific. While frequently reported in countries with large raw fish consumption as Japan, the global prevalence of anisakiasis may be severely underestimated due to limitations of available diagnostic tools and to diverse clinical manifestations. Recently, infective larvae were found in the same localization with gastrointestinal tumors. The occurrence of allergic exacerbation upon secondary exposure and the possible occupational exposure, highlight the need to increase scientific evidences on anisakiasis.

Methods

We performed a retrospective descriptive study using analysis of Hospital Discharge Records (HDRs) from 2005 to 2015 in Italy, with particular attention to allergic manifestations. Descriptive statistics and multivariate analyses were performed using backward step-wise logistic regression models to assess spatial distribution and temporal trend as well as the variables independently associated with the allergic clinical signs and symptoms in Italian cases of anisakiasis.

Results

HDRs reporting the ICD-9 code for anisakiasis were retrieved (370), with a higher number of cases reported from central and southern regions, with particular regard to populations inhabiting the coastal territories. Around 40% of patients presented allergic manifestations and half of them showed serious allergic reactions. The multivariate analyses showed an independent association between allergic manifestations and features as living in southern regions and female gender, while anaphylactic episodes was independently associated only with female gender.

Conclusion

The present study is the first attempt to a better understanding of the epidemiological picture of anisakiasis in Italy, mining official data. A common strategy on data collection, monitoring and reporting would favor a more accurate epidemiological scenario in Italy, since the report of the diseases is not mandatory.

Unexpected Echinococcus multilocularis infections in shepherd dogs and wolves in south-western Italian Alps: A new endemic area?

The European distribution of Echinococcus multilocularis has been reported to be expanding east and north, whereas its southern limits are deemed stable. During a study on Echinococcus granulosus s.l. infections in wolves and dogs in the Italian Maritime Alps, we unexpectedly detected the presence of E. multilocularis eggs in four fecal samples from at least two shepherd dogs, and in five wolf fecal samples. This finding, in an area about 130 km south of the southernmost E. multilocularis report in the Alps, may suggest a rapid expansion southward. While infections in foxes are currently being investigated, these data seem to indicate the potential for a new E. multilocularis endemic area. If this will be confirmed, the implementation of surveillance programs in wild and domestic canids and preventative measures will become a priority.

Molecular identification of Mesocestoides sp. metacestodes in a captive gold-handed tamarin (Saguinus midas)

Mesocestoides spp. are tapeworms harbored in the intestine of many domestic and wild carnivores, birds of prey and, rarely, of humans. The life cycle is assumed to involve three hosts and the metacestode juvenile stage (tetrathyridium) may reproduce asexually, provoking severe systemic infections. In the present study, a case of a peritoneal infection by Mesocestoides sp. occurred in a captive gold-handed tamarin (Saguinus midas) is described. Phylogenetic positions based on CO1 and 12S loci were analysed to describe in details this unusual finding of Mesocestoides in a callitrichid monkey. The phylogenetic analyses has not clearly resolve relationships between the metacestode forms from the tamarin and any of the described Mesocestoides species available so far, including those described from non-human primates, thus supporting the hypothesis of a new taxon within the genus.

Tissue-specific transcriptomes of Anisakis simplex (sensu stricto) and Anisakis pegreffii reveal potential molecular mechanisms involved in pathogenicity

Background

Larval stages of the sibling species of parasitic nematodes Anisakis simplex (sensu stricto) (s.s.) (AS) and Anisakis pegreffii (AP) are responsible for a fish-borne zoonosis, known as anisakiasis, that humans aquire via the ingestion of raw or undercooked infected fish or fish-based products. These two species differ in geographical distribution, genetic background and peculiar traits involved in pathogenicity. However, thus far little is known of key molecules potentially involved in host-parasite interactions. Here, high-throughput RNA-Seq and bioinformatics analyses of sequence data were applied to the characterization of the whole sets of transcripts expressed by infective larvae of AS and AP, as well as of their pharyngeal tissues, in a bid to identify transcripts potentially involved in tissue invasion and host-pathogen interplay.

Results

Approximately 34,000,000 single-end reads were generated from cDNA libraries for each species. Transcripts identified in AS and AP encoded 19,403 and 10,424 putative peptides, respectively, and were classified based on homology searches, protein motifs, gene ontology and biological pathway mapping. Differential gene expression analysis yielded 226 and 339 transcripts upregulated in the pharyngeal regions of AS and AP, respectively, compared with their corresponding whole-larvae datasets. These included proteolytic enzymes, molecules encoding anesthetics, inhibitors of primary hemostasis and virulence factors, anticoagulants and immunomodulatory peptides.

Conclusions

This work provides the scientific community with a list of key transcripts expressed by AS and AP pharyngeal tissues and corresponding annotation information which represents a ready-to-use resource for future functional studies of biological pathways specifically involved in host-parasite interplay.

Electronic supplementary material

The online version of this article (10.1186/s13071-017-2585-7) contains supplementary material, which is available to authorized users.

Genetic survey of alveolar and cystic echinococcoses in Romania: first molecular evidence of Echinococcus multilocularis in humans in the country

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are considered as one of the most important zoonotic diseases in Romania, where they are subject to mandatory reporting. To obtain more knowledge about the genetic diversity of Echinococcus causative agents of these diseases, 11 isolates from humans and ungulate intermediate hosts from the two regions of Romania were genotyped using mitochondrial markers. In clinical samples of five patients from north-eastern Romania (Iasi, Botosani, Vaslui counties), Echinococcus multilocularis was identified as causal agent by cox1 sequence analysis. To the best of our knowledge this finding presents the first molecular evidence of E. multilocularis in humans from Romania. Only two cases of AE in patients were previously documented in the country by serological methods. In our four patients the most widespread European variant E5 of E. multilocularis was recorded, whereas in isolate from Vaslui county three nucleotide substitutions were detected as compared to the most related E5 haplotype. One of these mutations (411T/G) matched N1 and N2 haplotypes described previously from North America. In six CE samples retrieved from western Romania (Caras-Severin and Timis counties), two human isolates were diagnosed as Echinococcus canadensis G7, one as E. granulosus s.s. G1 and one as E. granulosus s.s. G3 using atp6 and rrnS sequencing. In ungulates, the cattle isolate was allocated to E. granulosus s.s. G1 and pig isolate to E. canadensis G7. The two G7 findings in humans reinforced the recent view that G7 was underestimated as compared to the E. granulosus s.s. regarding human CE threat that can be further employed for identifying sources of infections and establishing suitable preventive measures.

Validation of a commercial kit aimed to the detection of pathogenic anisakid nematodes in fish products

Anisakids are parasitic nematodes responsible for a zoonosis that occurs following the ingestion of fish and fish products infected with larvae belonging to the genera Anisakis and Pseudoterranova. Rarely Contracaecum is found in association with gastric/intestinal illness, while Hysterothylacium is commonly considered not pathogenic. Although Real Time PCR assays have been recently used with the aim to detect and quantify these parasites in food products, methods applied did not undergo through extensive validation process, a feature highly desirable or mandatory in the case of testing laboratories accredited for the ISO EN 17025:2005. Here, a comprehensive study has been performed to validate a commercial kit based on multiplex real time PCR for the qualitative detection of Anisakis and Pseudoterranova. Inclusivity/exclusivity trials were carried out on DNA from species of the genera Anisakis, Pseudoterranova, Contracaecum, Hysterothylacium and Ascaris, on fish intentionally contaminated with Anisakis spp. and Pseudoterranova spp. and on marine organisms as fish, crustacean and squid to test the commercial kit on a large sample. The assay gave positive amplification for several Anisakis and Pseudoterranova species, while providing no signal for the members of the remaining genera. Each sample was correctly assigned either to Anisakis or Pseudoterranova, thus indicating that no cross-reaction occurred. The LOD was determined using two independent standard curves. Robustness was assayed by using two different thermocyclers in three distinct laboratories with different operators. The establishment of a validation dossier will permit the use of the commercial kit for the detection of Anisakis and Pseudoterranova DNA in fish and fish products intended for human consumption by public or private laboratories, following the requirements regarding the quality assurance processes described in the ISO EN 17025:2005.

Gasterophilus intestinalis (Diptera: Oestridae) in the diaphragmatic muscle: An unusual finding

Larval forms of the bot-fly Gasterophilus are obligate parasites commonly found in the gastrointestinal tract of equids, causing intestinal myiasis. Five species are reported so far in Italy, mostly observed during necroscopy, located in different portion of gastrointestinal tract of equids: G. intestinalis, G. nasalis, G. inermis, G. pecorum and G. haemorrhoidalis. An unusual finding of larval Gasterophilus intestinalis deeply inserted into the diaphragmatic muscle is here reported. Due to the uncommon localization, to the absence of clinical signs related to myiasis and subsequent uncertainty of species identity, identification was performed using an integrative taxonomical approach combining morphology with molecular tools for confirmatory reasons. This finding adds information on migration patterns of erratic larval forms in G. intestinalis, a feature of interest as gasterophiliasis is among the less studied intestinal myiasis of horses.

Spatial and Temporal Phylogeny of Border Disease Virus in Pyrenean Chamois (Rupicapra p. pyrenaica)

Border disease virus (BDV) affects a wide range of ruminants worldwide, mainly domestic sheep and goat. Since 2001 several outbreaks of disease associated to BDV infection have been described in Pyrenean chamois (Rupicapra pyrenaica pyrenaica) in Spain, France and Andorra. In order to reconstruct the most probable places of origin and pathways of dispersion of BDV among Pyrenean chamois, a phylogenetic analysis of 95 BDV 5'untranslated sequences has been performed on chamois and domestic ungulates, including novel sequences and retrieved from public databases, using a Bayesian Markov Chain Monte Carlo method. Discrete and continuous space phylogeography have been applied on chamois sequences dataset, using centroid positions and latitude and longitude coordinates of the animals, respectively. The estimated mean evolutionary rate of BDV sequences was 2.9×10-3 subs/site/year (95% HPD: 1.5-4.6×10-3). All the Pyrenean chamois isolates clustered in a unique highly significant clade, that originated from BDV-4a ovine clade. The introduction from sheep (dated back to the early 90s) generated a founder effect on the chamois population and the most probable place of origin of Pyrenean chamois BDV was estimated at coordinates 42.42 N and 1.9 E. The pathways of virus dispersion showed two main routes: the first started on the early 90s of the past century with a westward direction and the second arise in Central Pyrenees. The virus spread westward for more than 125 km and southward for about 50km and the estimated epidemic diffusion rate was about 13.1 km/year (95% HPD 5.2-21.4 km/year). The strong spatial structure, with strains from a single locality segregating together in homogeneous groups, and the significant pathways of viral dispersion among the areas, allowed to reconstruct both events of infection in a single area and of migrations, occurring between neighboring areas.

First case report of invasive pseudoterranoviasis in Italy

Members of the genera Anisakis and Pseudoterranova are the main causative agents of human anisakidosis: the disease is worldwide distributed, with major impact in countries with a large consumption of raw fish. Because of unspecific symptoms and limited diagnostic tools, incidence and burden of disease are probably underestimated. In Italy, all human infestations where the etiological agent has been properly identified, have been associated to the parasitic species Anisakis pegreffii, the most frequent anisakid in the Mediterranean area. Here, an invasive human case of pseudoterranoviasis is described for the first time in Italy: in 2015, a woman was found infected during a colonoscopy scheduled after the occurrence of nonspecific clinical symptoms. The nematode was found penetrating the ascending colon. The identification was performed by sequencing the mitochondrial region cox2 and by comparison to GenBank retrieved material using the BLAST search tool. The sample showed a 99% identity with Pseudoterranova decipiens sensu stricto. The record underlines the potential risk due to the consumption of raw or undercooked imported fishes.

A molecular survey of Echinococcus granulosus sensu lato in central-eastern Europe

Central-eastern Europe is an endemic region for cystic echinococcosis where multiple species of intermediate hosts are commonly infected with Echinococcus granulosus sensu lato tapeworms of major medical and veterinary importance. Investigations of the genetic variation of 25 Echinococcus isolates from five countries (Slovakia, Romania, Ukraine, Hungary, Poland) were undertaken using three mitochondrial DNA markers. The 18 isolates from pigs derived from Slovakia and Ukraine and the four human isolates from Slovakia, Poland and Ukraine were identified as E. canadensis G 7, whereas the three human isolates from Romania and Hungary were classified as E. granulosus sensu stricto G1. This study reports the first confirmed human case of E. granulosus s.s. in Hungary. The haplotype G7A with two polymorphic sites relative to the most common regional variant of E. canadensis G7 was recorded in both pigs from Ukraine and in a single pig isolate from Slovakia. The results of this study support the circumstantial evidence that E. canadensis G7 with low infectivity for humans is highly prevalent in the northern parts of the region (Poland, Slovakia, forest-steppe zone of Ukraine), while infections with E. granulosus s.s. which are highly infectious for humans are more commonly encountered in Romania and Hungary.

Genetic heterogeneity and phylogeny of Trichuris spp. from captive non-human primates based on ribosomal DNA sequence data

Nematodes of the genus Trichuris, known as whipworms, are recognized to infect numerous mammalian species including humans and non-human primates. Several Trichuris spp. have been described and species designation/identification is traditionally based on host-affiliation, although cross-infection and hybridization events may complicate species boundaries. The main aims of the present study were to genetically characterize adult Trichuris specimens from captive Japanese macaques (Macaca fuscata) and grivets (Chlorocebus aethiops), using the ribosomal DNA (ITS) as molecular marker and to investigate the phylogeny and the extent of genetic variation also by comparison with data on isolates from other humans, non-human primates and other hosts. The phylogenetic analysis of Trichuris sequences from M. fuscata and C. aethiops provided evidences of distinct clades and subclades thus advocating the existence of additional separated taxa. Neighbor Joining and Bayesian trees suggest that specimens from M. fuscata may be distinct from, but related to Trichuris trichiura, while a close relationship is suggested between the subclade formed by the specimens from C. aethiops and the subclade formed by T. suis. The tendency to associate Trichuris sp. to host species can lead to misleading taxonomic interpretations (i.e. whipworms found in primates are identified as T. trichiura). The results here obtained confirm previous evidences suggesting the existence of Trichuris spp. other than T. trichiura infecting non-human living primates.

Survey of Anisakis sp. and Hysterothylacium sp. in sardines and anchovies from the North Adriatic Sea

The occurrence of larval Anisakidae and Raphidascarididae in anchovies and sardines from the North Adriatic Sea has been estimated. Anisakis pegreffii and Hysterothylacium aduncum were reported, with low prevalence values. In brief, a total amount of 7650 fish specimens collected between September 2011 and 2012 were analysed using three different inspection analyses: a visual inspection of the coelomic cavity, an examination of the viscera exploiting the positive hydro-tropism of the larvae (modified Baermann technique) and enzymatic digestion of muscular tissue pools. Low level of infestation was reported for Anisakis sp. in both in anchovies and sardines, while higher values were reported for Hysterothylacium sp. Subsamples of nematodes collected were characterized at species level using the molecular diagnostic key based on ITS nuclear ribosomal region, and A. pegreffii and H. aduncum were identified. The low prevalence of Anisakis sp. in sardines and anchovies from the North Adriatic Sea could be related to the peculiar distribution of cetaceans and carnivorous zooplankton in the investigated region and could be used as a potential tag to define oily fishes from this specific fishing area as at low-risk for anisakiasis.

Putative hybrids between two Anisakis cryptic species: molecular genotyping using High Resolution Melting

The genus Anisakis includes nine recognized species and the complex of cryptic species Anisakis simplex s. l. is often associated with the human disease known as anisakiasis. During the last decades the use of nuclear ribosomal ITS allowed the identification and description of numerous anisakid nematodes and the discovery of recombinant genotypes or putative hybrids even in other parasitic helminths, such as those between A. simplex sensu stricto and A. pegreffii. The existence of pure hybrids of the two sibling species has been long debated due to the large recovery of larval forms from sympatric areas and the rare observation of adult hybrids. The aims of the present report were to identify anisakid nematodes collected from Stenella coeruleoalba using PCR-RFLP of ITS and to focus the interest on hybrid forms using a High Resolution Melting (HRM) and direct sequencing analyses, since the new record of putative hybrid at adult stage. The PCR-RFLP analysis enabled to identify A. simplex s.s., A. pegreffii, the heterozygous genotype of the two species and A. physeteris. The use of the genotyping approach based on HRM confirmed the profiles of the two species A. simplex s.s. and A. pegreffii, and of the hybrid individuals. The new record of adult hybrids in definitive hosts rekindles the long debate about their existence and their evolutionary meaning. Since the reproductive isolation between A. simplex s.s. and A. pegreffii is the assumption for their existence as separated species, the use of alternative molecular markers and population genetic studies on adult anisakids are recommended.

Presence of anisakid larvae in the European anchovy, Engraulis encrasicolus, fished off the Tyrrhenian coast of central Italy

A survey was carried out to determine the prevalence of anisakid nematode larvae in European anchovy (Engraulis encrasicolus) fished off the Tyrrhenian coast of central Italy. From February through July 2012, 1,490 specimens of E. encrasicolus caught in three different fishing areas (off Civitavecchia, Anzio, and Gaeta in the northern, central, and southern Lazio region of Italy, respectively) were tested for the presence of anisakid larvae, both by visual microscopic inspection and enzymatic digestion. In each of the three fishing areas, each of two sampling times produced 250 fish (with the exception of one sampling time in Gaeta that produced 240 fish). Larvae of the family Anisakidae were detected with an overall estimated prevalence of 2.3%, and each positive fish harbored a single larva. No anisakid larvae were detected in fish caught off Gaeta. Fish with larvae were significantly longer (standard length) than fish without larvae. Twenty-six larvae (74.3%) were detected by visual inspection of the viscera, eight larvae (22.8%) were detected by visual inspection of the fillets, and one larva (2.8%) was detected after digestion of pooled fillets. Molecular analysis to fully characterize the 35 detected larvae revealed 15 specimens of Anisakis pegreffii, 10 specimens of Hysterothylacium aduncum, and one hybrid genotype of A. pegreffii × Anisakis simplex. For nine specimens, no visible product was obtained after PCR amplification. The overall prevalence for A. pegreffii and H. aduncum was 1.0 and 0.7%, respectively. A comparison between fishes harboring A. pegreffii larvae and those harboring H. aduncum revealed that those with A. pegreffii were significantly heavier. The prevalence of anisakid larvae found in the present study is lower then that reported previously in E. encrasicolus collected in the Mediterranean Sea.

Phylogeographical studies of Ascaris spp. based on ribosomal and mitochondrial DNA sequences

Background

The taxonomic distinctiveness of Ascaris lumbricoides and A. suum, two of the world's most significant nematodes, still represents a much-debated scientific issue. Previous studies have described two different scenarios in transmission patterns, explained by two hypotheses: (1) separated host-specific transmission cycles in highly endemic regions, (2) a single pool of infection shared by humans and pigs in non-endemic regions. Recently, A. suum has been suggested as an important cause of human ascariasis in endemic areas such as China, where cross-infections and hybridization have also been reported. The main aims of the present study were to investigate the molecular epidemiology of human and pig Ascaris from non-endemic regions and, with reference to existing data, to infer the phylogenetic and phylogeographic relationships among the samples.

Methodology

151 Ascaris worms from pigs and humans were characterized using PCR-RFLP on nuclear ITS rDNA. Representative geographical sub-samples were also analysed by sequencing a portion of the mitochondrial cox1 gene, to infer the extent of variability at population level. Sequence data were compared to GenBank sequences from endemic and non-endemic regions.

Principal Findings

No fixed differences between human and pig Ascaris were evident, with the exception of the Slovak population, which displays significant genetic differentiation. The RFLP analysis confirmed pig as a source of human infection in non-endemic regions and as a corridor for the promulgation of hybrid genotypes. Epidemiology and host-affiliation seem not to be relevant in shaping molecular variance. Phylogenetic and phylogeographical analyses described a complex scenario, involving multiple hosts, sporadic contact between forms and an ancestral taxon referable to A. suum.

Conclusions/Significance

These results suggest the existence of homogenizing gene flow between the two taxa, which appear to be variants of a single polytypic species. This conclusion has implications on the systematics, transmission and control programs relating to ascariasis.

Ascaris lumbricoides, the world's most common human nematode, and A. suum, the pig roundworm, are two of the most important soil-transmitted helminthes of public health and socio-economic concern. However, previously documented similarities at the morphological and genetic level, coupled with evidence for hybridization and gene flow, have clouded the taxonomic distinctiveness of these two nematodes. To date, molecular epidemiological studies have been carried out, mostly in highly endemic regions, where two different transmission cycles have been described. Recently, pigs have been recognized as an important source of human ascariasis in China, opening questions about the zoonotic potential and the efficiency of control programs. Here, samples from non-endemic regions have been analysed using a nuclear marker to identify nematodes to species level plus a mitochondrial marker to investigate the phylogeographic relationships among individuals of the two species from both endemic and non-endemic regions. Results obtained suggested that A. suum and A. lumbricoides may be variants of the same species, with the lack of fixed genetic differences and considerable phylogeographic admixture confirming an extremely close evolutionary relationship among these nematodes. This study highlights the need to further explore the evolutionary affinities of the two taxa to help shed light on the epidemiology of ascariasis.

Interactions between parasites and microbial communities in the human gut

The interactions between intestinal microbiota, immune system, and pathogens describe the human gut as a complex ecosystem, where all components play a relevant role in modulating each other and in the maintenance of homeostasis. The balance among the gut microbiota and the human body appear to be crucial for health maintenance. Intestinal parasites, both protozoans and helminths, interact with the microbial community modifying the balance between host and commensal microbiota. On the other hand, gut microbiota represents a relevant factor that may strongly interfere with the pathophysiology of the infections. In addition to the function that gut commensal microbiota may have in the processes that determine the survival and the outcome of many parasitic infections, including the production of nutritive macromolecules, also probiotics can play an important role in reducing the pathogenicity of many parasites. On these bases, there is a growing interest in explaining the rationale on the possible interactions between the microbiota, immune response, inflammatory processes, and intestinal parasites.

Polymorphisms at MHC class II DRB1 exon 2 locus in Pyrenean chamois (Rupicapra pyrenaica pyrenaica)

Chamois (Rupicapra spp.) are mountain ungulates from Southern and Central Europe and the Near East. A newly reported border disease virus (BDV) has affected the easternmost populations of Pyrenean chamois, leading to a dramatic population decrease that may drive to genetic variability loss. The Major Histocompatibility Complex (MHC) is a sensitive marker for genetic variation of populations: polymorphism on the MHC genes is affected both by pathogens and population dynamics and it is ecologically relevant, as depending on host-pathogen relationships and life history features. In the present study MHC class II DRB1 exon 2 variation was investigated in 81 Pyrenean chamois (Rupicapra pyrenaica pyrenaica) belonging to four populations. Haplotype analysis, population genetics statistics and network analysis were carried out, in order to analyze variability, phylogeography and genealogy, and the effects of geography and demographic trend. Twenty-nine haplotypes were identified, 26 of them newly described, with high Gene diversity (Gd). The variability observed in the easternmost populations of Pyrenean chamois showed a higher genetic diversity than that previously reported for other populations of Pyrenean and Cantabrian chamois (Rupicapra pyrenaica parva). The most frequent allele was RupyDRB*15, previously undetected, which seems to play a significant role in genotyping the variability, suggesting a possible effect of positive selection.

Genetic structure of Ascaris roundworm in Japan and patterns of its geographical variation

Ascaris roundworm isolates from Japan and central Europe were examined by sequencing analyses to better understand geographically induced nucleotide variation and genotype distribution according to host. Three well-supported clusters (denoted as A, B, C) were identified by generating cox1 sequences of mtDNA from these regions. Among 5 pig isolates collected in eastern Honshu, Japan, in 2010, 3 carried DNA characteristics for cluster A and 2 corresponded with the characteristics of cluster B. The sequence of the human isolate JH1 from north-central Honshu, fixed in formalin since 1972, conformed to the characteristics of cluster A. Differential analysis of ribosomal ITS1 region revealed the JH1 isolate sequence profile of Ascaris lumbricoides. Cluster C, which was the most distinguish cluster, was formed by reference Slovak isolates and has been so far found almost exclusively in European pigs. A fluctuating prevailing distribution of A and B lineages in human and pig hosts in different territories of the world and the global distribution of several haplotypes indicate their establishment before secondary differentiation in a given region due to host affiliation. The protocol established for DNA isolation from formalin-fixed specimens using the modified procedure with the Qiagen extraction set can be used as a tool for retrospective studies in ascarid helminths when only archival specimens are available.

Acute sodium overload produces renal tubulointerstitial inflammation in normal rats

The aim of the present study was to determine whether acute sodium overload could trigger an inflammatory reaction in the tubulointerstitial (TI) compartment in normal rats. Four groups of Sprague-Dawley rats received increasing NaCl concentrations by intravenous infusion. Control (C): Na+ 0.15 M; G1: Na+ 0.5 M; G2: Na+ 1.0 M; and G3: Na+ 1.5 M. Creatinine clearance, mean arterial pressure (MAP), renal blood flow (RBF), and sodium fractional excretion were determined. Transforming growth factor beta1 (TGF-beta1), alpha-smooth muscle actin (alpha-SMA), RANTES, transcription factor nuclear factor-kappa B (NF-kappaB), and angiotensin II (ANG II) were evaluated in kidneys by immunohistochemistry. Animals with NaCl overload showed normal glomerular function without MAP and RBF modifications and exhibited a concentration-dependent natriuretic response. Plasmatic sodium increased in G2 (P < 0.01) and G3 (P < 0.001). Light microscopy did not show renal morphological damage. Immunohistochemistry revealed an increased number of ANG II-positive tubular cells in G2 and G3, and positive immunostaining for NF-kappaB only in G3 (P < 0.01). Increased staining of alpha-SMA in the interstitium (P < 0.01), TGF-beta1 in tubular cells (P < 0.01), and a significant percentage (P < 0.01) of positive immunostaining for RANTES in tubular epithelium and in glomerular and peritubular endothelium were detected in G3 > G2 > C group. These results suggest that an acute sodium overload is able 'per se' to initiate TI endothelial inflammatory reaction (glomerular and peritubular) and incipient fibrosis in normal rats, independently of hemodynamic modifications. Furthermore, these findings are consistent with the possibility that activation of NF-kappaB and local ANG II may be involved in the pathway of this inflammatory process.

Fructose overload modifies vascular morphology and prostaglandin production in rats

1. A fructose (Fru)-enriched diet induces a mild increase in blood pressure associated with hyperglycaemia, hypertriglyceridaemia, and insulin resistance, resembling the human 'syndrome X', being an useful model to study hypertension and type 2 diabetes. 2. A sustained elevation of blood pressure is associated with cardiovascular structural modifications such as left ventricular hypertrophy and increased wall thickness:lumen diameter ratio in blood vessels. 3. Prostanoids (PR), metabolites of arachidonic acid through the cyclooxygenase pathway, include vasoactive substances synthesized and released by the vessel walls. 4. The aim of the present study was to analyse, in Fru-treated rats: (i) the morphology of mesenteric vessels and; (ii) the PR production in aorta and mesenteric vessels, in order to assess whether these parameters are related with the haemodynamic alterations observed in this experimental model. 5. Blood pressure, glycaemia and triglyceridaemia, were significantly elevated in both (4 and 22 weeks) Fru-treated groups. Meanwhile body and heart weight as well as insulinaemia were similar between experimental animals and controls. 6. The mesenteric vessels of Fru-treated rats (22 weeks) showed an increased thickness and area of the media when compared with the controls; meanwhile, the lumen diameter was similar in both groups. 7. The Fru treatment for 4 weeks did not modify PR production in aorta, whereas in the mesenteric bed it diminished prostaglandin (PG) E(2) release significantly compared with the controls. However, in the group treated for 22 weeks, Fru reduced PGI(2) production in the aorta, as assessed by 6-keto-PGF(1)alpha measurements. Meanwhile, in the mesenteric bed, the chronic Fru treatment decreased PGE(2) release but, rather surprisingly, increased the output of PGI(2) when compared with its corresponding controls. 8. In conclusion, the present study shows the existence of an alteration in the morphology of mesenteric vessels in Fru-treated rats, which could be related to an increase in peripheral resistance and the consequent mild hypertension observed in this model. However, a diminished release of vasodilator PRs, such as PGE(2) in mesenteric vessels at 4 and 22 weeks and PGI(2) in aorta at 22 weeks could further impair the vessel response. The increase in PGI(2) observed in the chronic group in mesenteric vessels could be attributed to a compensatory mechanism.

Impaired response to insulin associated with protein kinase C in chronic fructose-induced hypertension

A fructose-enriched diet induces an increase in blood pressure associated with metabolic alterations in rats. Our hypothesis was that an increase in protein kinase C (PKC) activation, reported in the acute period of fructose overload, and an impaired vessel's response to vasoactive substances contribute to maintain elevated blood pressure levels in the chronic period. The aims of this study were to investigate in this animal model of hypertension: (1) if the increase in PKC activation was also found in the chronic stage; (2) the involvement of nitric oxide and insulin in the vessel's response; and plasma atrial natriuretic factor and nitrites/nitrates (nitric oxide metabolites) behavior. We evaluated the effects of: PKC-stimulator 12,13-phorbol dibutyrate, phenylephrine, insulin, nitric oxide synthase-inhibitor NG-nitro-L-arginine methyl esther (L-NAME) and PKC-inhibitor Calphostin C on aortic rings responses of Sprague-Dawley rats: fructose-fed and control. The fructose-fed group showed higher contractility to 12,13-phorbol dibutyrate than the control group in aortic rings pre-incubated with insulin, and this difference disappeared with L-NAME. The response to phenylephrine in rings pre-incubated with Calphostin C was decreased in the fructose-fed group and increased with Calphostin C plus L-NAME. Fructose-fed rats showed higher levels of plasma atrial natriuretic factor and nitrites/nitrates than controls. In conclusion, chronic fructose feeding seems to develop an impaired response to insulin, dependent on nitric oxide, suggesting a PKC alteration. Vasorelaxant agents, such as atrial natriuretic factor and nitric oxide, would behave as compensatory mechanisms in response to high blood pressure.