Susceptibility to Infectious Diseases in Obesity

The role of intestinal microbiota is becoming ever more important in the context of obesity, type II diabetes (T2D), and infectious disorders as represented by the emerging discipline "therapeutic microbiology". The gut microbiota is strictly interconnected with obesity and T2D playing also an important role in immune system regulation.

Obesity and diabetes can lead to chronic inflammation, which results in the secretion of pro-inflammatory cytokines like IL-6, IL-1, and TNF-alpha, causing immune system alteration which predisposes patients with obesity and T2D to chronic infections. Therefore, the principal aim of the study is to investigate changes in gut microbiota composition between patients with chronic infections or not, so as to attribute to specific phyla the formation of the infections in these patients.

Obesity is nowadays a relevant public issue, with more than 650 million people affected worldwide. By definition, obesity is characterized by excessive calorie intake and lowering energy expenditure favored today by the increased sedentary lifestyle and junk food availability. Obesity represents a risk factor for cardiovascular diseases, neoplasm, and first of all type II diabetes. Nonetheless, obesity increases susceptibility to infectious disorders such as urinary tract infections, periodontitis, herpes virus infection, and also Covid-19. During the pandemic, obese patients were interested in the severe form of Covid-19 and also they presented less response to the vaccine.

Because of insulin resistance and chronic inflammation, typical of obese patients, T2D is a classical comorbidity presented by these individuals. Together these two pathologies lead to immune system deregulation and a high predisposition to secondary infections. A third player is the gut microbiota, recent discoveries demonstrated as intestinal microbiota is strictly interconnected with obesity and diabetes and with the circadian clock. Being the gut microbiota an important regulator of the immune system changes in gut microbiota composition induced by diet, obesity, and T2D can be reflected in the impairment of the immune system.

The purpose of the present study is the investigation of the gut microbiota signature in patients presenting obesity and T2D with or without infectious diseases. The idea is the identification of microbiota composition about pathological, metabolomic, and socio-economic features. Obtained results from this study could be used for the identification of new therapeutic targets involved in the development of these pathologies.

Eligibility Criteria:
Inclusion Criteria:

* age between 18-65 years
* ability to understand the study protocol
* obesity with BMI between 30-40 kg/m2
* affects by type II diabetes
* presence/absence of chronic infections
* the possibility of equality in the two groups (matched for sex, age, and therapies)

Exclusion Criteria:

* psychological conditions that reduced the ability the comprehension of the study protocol
* subjects undergoing a diet-therapeutic regimen;
* subjects with the possibility of developing diabetic foot in the successive months
* patients with relapsing infections
* pregnancy
* bariatric surgery
* oncological and hematological pathologies
* Hypogonadism
* severe immunodepression
* vaccination in the last two weeks
* Alcohol or drug abuse
* antibiotic therapy