Growth factors in relation to obesity, food habits, and microbiota among healthy Saudis: preliminary results.

OBJECTIVE: Obesity is a serious problem among Saudis because of the country's affluent lifestyle. Obesity is associated with various metabolic disorders and characterized by low-grade inflammation that leads to the release of pro-inflammatory cytokines, human growth factors (GFs), lipids, aberrant adipokines, and other chemokines from adipose tissue. The objective of this study is to delineate the effects of GFs on microbiota and their relationship to body mass index (BMI) and food habits. SUBJECTS AND METHODS: In a cross-sectional study, 32 randomly selected participants (16 males and 16 females) were enrolled in a survey covering their sociodemographic information, medical history, lifestyle, and dietary practices. The information on diet, health condition, food and drink intake habits were examined under four distinct BMI categories: normal, underweight, overweight, and obese. The participants' serum samples were analyzed for the various GFs using a human magnetic 30-plex panel multiplex assay. Bioinformatics analysis was performed to investigate which bacterial taxa are enriched and to predict the functional profiles of the samples. RESULTS: Correlational studies revealed sex-based differences between GFs and microbiota. Females exhibited a significant correlation between epidermal GF (EGF) and Proteobacteria, whereas males showed a significant correlation between fibroblast GF-basic and Actinobacteria. Interestingly, a combined analysis of both sexes showed a significant correlation between EGF and vascular endothelial GF with Firmicutes. The data in the underweight group revealed a correlation between granulocyte colony-stimulating factor (G-CSF) and hepatocyte GF with Firmicutes. In the obese group, a correlation was found between G-CSF and Actinobacteria. CONCLUSIONS: Our results identified links between GFs, microbiota, and BMI in a Saudi cohort. The insights from this preliminary study will contribute to the predictive diagnosis of obesity. However, further research involving a larger cohort will be necessary to understand the mechanistic aspects of these GFs to provide biomarkers of potential obesity.

Asymptomatic canine leishmaniasis in Greater Athens area, Greece.

Leishmania (L.) infantum is the etiological agent of human and canine visceral leishmaniasis in the Mediterranean subregion. Domestic dogs are the main reservoir of the parasite in most urban areas. A survey of 1638 asymptomatic dogs registered in Greater Athens area was carried out in the Hellenic Pasteur Institute during the period 1986-1994 to investigate the prevalence of canine visceral leishmaniasis in apparently healthy dogs. Dog sera was tested using the indirect fluorescent antibody technique (IFAT). Of the 1638 dogs, 366 (22.4%) had anti-Leishmania infantum antibodies at titre greater than or equal to 1/200 which were considered positive; 53 (3.2%) had antibody titres of 1/100 and were considered uncertain; and 1219 (74.4%) dogs were seronegative. From the 366 seropositive dogs, 212 were positive at 1/1600 serum dilution, 57 at 1/800, 38 at 1/400 and 59 at 1/200. The results were plotted according the site of residence, breed and age. The rate of asymptomatic infections with L. infantum dogs in Greater Athens area appears to be significantly high. Although there is an apparent lack of clinical symptoms in these dogs, asymptomatic animals harbor a chronic L. infantum infection and as such consist a 'dangerous' reservoir with regard to the spread of the disease.

ISCOMs vaccine against experimental leishmaniasis.

The major surface glycoprotein (gp63) of Leishmania major incorporated into the immunostimulating complexes (ISCOMs) was used to protect Balb/c mice against experimental infection. Two intraperitoneal vaccinations with low doses of gp63 into ISCOMs (gp63-ISCOMs) induced protective immunity in vaccinated mice as indicated by reduced inflammation and suppressed lesions after experimental challenge. An augmented IgG-specific secretion and a specific switching towards the IgG2a isotype was observed in the serum of vaccinated mice. Gp63-ISCOMs primed spleen cells restimulated in vitro with soluble Leishmania antigen (SLA) or live parasites displayed strong gp63-specific proliferative responses and secreted high levels of interleukin-2, interferon gamma and interleukin-10 but not interleukin-4. No delayed type hypersensitivity response to either SLA or LV39 was detected. These data indicate that gp63-ISCOMs induced a protective immunity in the susceptible Balb/c mice against Leishmania challenge, modulating the immune response towards a Th1 rather than Th2 type.

Canine visceral leishmaniasis in the great Athens area, Greece.

A survey of 1,175 dogs with suspected visceral leishmaniasis (VL), was carried out to investigate canine leishmaniasis in the Athens basin, the largest metropolitan area of Greece. The dogs examined were not a random sample since animals were selected on the basis of symptoms indicating the disease. Dog sera were tested using the indirect fluorescent antibody technique (IFAT), with titres greater than or equal to 1/200 considered positive for VL. On this basis 569 dogs (48.4%) were found positive for VL and 69 (5.9%) borderline (with titres of 1/100). Additionally, 218 of these sera were also tested by enzyme-linked immunosorbent assay (ELISA). Of this sample, 120 were negative and 88 were positive with both IFAT and ELISA (according to the stated criteria), and thus the concordance of the two methods was 98.6%. Dogs positive for VL were classified according to age, sex, breed, and area of residence. Dogs from outlying areas of the Athens basin had higher infection rates than dogs from the city. The most affected breed was the Doberman, and the least affected was the Collie.