Genetic, Immunological, Dietary, Gut Microbiota, and Environmental Determinants of Osteoporosis in the Course of Celiac Disease: Which Factor Plays the First Violin in This Orchestra?

Celiac disease (CD) is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals. The worldwide prevalence of CD is estimated to be 0.7-1.4% of the general population. Etiopathology of this disease is multifactorial, with genetic determinants being a major contributing player to CD susceptibility. Its manifestation embraces different organs, including the musculoskeletal apparat. Patients with CD have increased risk of bone disorders. According to data, bone disorders - osteopenia and osteoporosis - can affect up to 70% of patients with CD at diagnosis, and it decreases after the initiation of a gluten-free diet. Gluten consumption in patients with CD triggers an inflammatory reaction followed by tissue damage, and both; local and systemic inflammation can increase the risk of bone mass deterioration. Other theory assumes shortages of vitamin D and an impaired calcium absorption mechanism leading to secondary hyperparathyroidism. Taking into account the increasing prevalence of CD and osteoporosis, we broadly discuss genetic, immunological, dietary, gut microbiota, and environmental factors that could increase the risk of osteoporosis in CD. Furthermore, we discuss lifestyle and pharmacological preventing and treatment measures.

Low-Penetrance Susceptibility Variants in Colorectal Cancer-Current Outlook in the Field.

Colorectal cancer (CRC) is one of the most frequent and mortality-causing neoplasia, with various distributions between populations. Strong hereditary predispositions are the causatives of a small percentage of CRC, and most cases have no transparent genetic background. This is a vast arena for exploring cancer low-susceptibility genetic variants. Nonetheless, the research that has been conducted to date has failed to deliver consistent conclusions and often features conflicting messages, causing chaos in this field. Therefore, we decided to organize the existing knowledge on this topic. We screened the PubMed and Google Scholar databases. We drew up markers by gene locus gathered by hallmark: oncogenes, tumor suppressor genes, genes involved in DNA damage repair, genes involved in metabolic pathways, genes involved in methylation, genes that modify the colonic microenvironment, and genes involved in the immune response. Low-penetration genetic variants increasing the risk of cancer are often population-specific, hence the urgent need for large-scale testing. Such endeavors can be successful only when financial decision-makers are united with social educators, medical specialists, genetic consultants, and the scientific community. Countries' policies should prioritize research on this subject regardless of cost because it is the best investment. In this review, we listed potential low-penetrance CRC susceptibility alleles whose role remains to be established.

NTHL1 Gene Mutations in Polish Polyposis Patients-Weighty Player or Vague Background?

Multiple polyposes are heterogeneous diseases with different underlying molecular backgrounds, sharing a common symptom: the presence of transforming into cancerous intestinal polyps. Recent reports have indicated biallelic mutations in the NTHL1 gene, which is involved in base excision repair (BER), as predisposing to an elevated risk of colorectal cancer (CRC). We aimed to evaluate the significance of the p.Q82* truncating variant in predisposition to intestinal polyposis by assessing its frequency in polyposis patients. We genotyped 644 Polish patients and 634 control DNA samples using high-resolution melting analysis (HRM) and Sanger sequencing. We found the p.Q82* variant in four polyposis patients; in three, it was homozygous (OR = 6.90, p value = 0.202). Moreover, the p.R92C mutation was detected in one patient. We also looked more closely at the disease course in patients carrying NTHL1 mutations. Two homozygous patients also presented other neoplasia. In the family case, we noticed the earlier presence of polyps in the proband and early hepatoblastoma in his brother. We cannot univocally confirm the relationship of p.Q82* with an increased risk of CRC. However, homozygous p.Q82* was more frequent by 10-fold in patients without other mutations identified, which makes NTHL1 gene screening in this group reasonable.

Vitamin D, Vitamin D Receptor (VDR) Gene Polymorphisms (ApaI and FokI), and Bone Mineral Density in Patients With Inflammatory Bowel Disease.

In the etiology of inflammatory bowel disease (IBD) and osteoporosis, the connecting element is the involvement of environmental and genetic factors. Vitamin D receptor (VDR) gene polymorphisms may be associated with the pathogenesis of IBD and bone mineral density (BMD). The study aimed to analyze the relationship between ApaI and FokI polymorphisms of the VDR gene, serum vitamin D concentration, and BMD in patients with IBD. The studied group consisted of 172 patients (85 with Crohn's disease [CD], 87 with ulcerative colitis [UC], and 39 healthy subjects - control group [CG]) were examined. Lumbar spine densitometry (L1-L4) and the femoral neck (FN) measurements were performed using dual-energy X-ray absorptiometry (DXA). Serum concentrations of 25-hydroxyvitamin D were determined using electrochemiluminescence binding assay (ECLIA). Polymorphisms were determined with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). . We found no statistically significant differences in vitamin D concentration between the 3 studied groups. CD patients who were FF homozygotes had significantly lower FN BMD than FF homozygous from CG (p-value < 0.05). CD patients who were Aa heterozygotes had significantly lower lumbar spine (L2-L4) BMD than Aa heterozygotes from CG (p-value < 0.05). Among patients with the same polymorphic variants, but belonging to different studied groups, statistically significant differences in bone mineral density in the lumbar spine and the closer end of the femoral neck were observed. We consider that it is the disease entity, not the polymorphism variant, may have a decisive impact on BMD.

Immunogenetic, Molecular and Microbiotic Determinants of Eosinophilic Esophagitis and Clinical Practice-A New Perspective of an Old Disease.

Eosinophilic oesophagitis (EoE) is a chronic, allergic disease associated with a T-lymphocyte response inducing esophageal eosinophilic infiltration in the esophagus. Inflammation and tissue fibrosis are responsible for the main clinical symptoms such as food impaction and dysphagia. The etiopathogenesis is multifactorial in which genetic and environmental factors coexist. The most common trigger is a non-IgE-mediated food allergy to milk, wheat, egg, soybean, nuts, fish, and seafood. The second factor we focus on is the contribution of genetic variation to the risk of EoE, describing the expression profile of selected genes associated with eosinophilic oesophagitis. We raise the topic of treatment, aiming to eliminate inflammation through an elimination diet and/or use of pharmacologic therapy with the use of proton pump inhibitors or steroids and endoscopic procedures to dilate the esophagus. We demonstrate that early diagnosis and effective treatment prevent the development of food impaction and decreased quality of life. The increasing presence of EoE requires bigger awareness among medical specialists concerning clinical features, the course of EoE, diagnostic tools, and management strategies.

Polymorphic variants in genes related to stress coping are associated with the awake bruxism.

BACKGROUND: Chronic stress is one of the leading predisposing factors in bruxism aetiology, but the influence of genetic factors is also suggested. We aimed to study whether sequence variants in genes involved in stress regulation pathways: NTRK2 and BDNF, may be associated with awake bruxism susceptibility, clinical presentation, and patients' perceived stress level. METHODS: The study group included 104 patients with probable awake bruxism and 191 population controls. Patients underwent dental examination concerning the symptoms of bruxism and psychological testing. Genotyping was performed using HRMA and sequencing. Statistical analyses were conducted, and P values below 0.05 were considered statistically significant. RESULTS: We observed a positive correlation of measured stress level and pathological teeth attrition in the anterior segment (r = 0.45, P < 0.001), enamel attritions (r = 0.44, P < 0.001), tongue impressions (r = 0.50, P < 0.001) and posterior teeth attrition (r = 0.27, P = 0.005). Moreover, the c.196A variant (p.66Met) of the BDNF gene and c.1397-31392G allele of the NTRK2 gene were present with elevated frequency, comparing to controls. CONCLUSIONS: This study hence the thesis that perceived stress level is a substantial contributing factor to awake bruxism occurrence and its clinical manifestations. Moreover, sequence variants in genes related to stress coping may be correlated with awake bruxism's susceptibility via elevated perceived stress level.

Colorectal carcinoma in the course of inflammatory bowel diseases.

BACKGROUND: Colorectal cancer (CRC) and inflammatory bowel disease (IBD) are the most prevalent diseases of the digestive system, and their association is unequivocal. A long-standing inflammatory process is one of the causes of sporadic as well as inherited cancers as it impacts on malignant transformation in a wide variety of neoplastic diseases, including colorectal cancer. METHODS: An extensive publication search was performed in Medline and PubMed database. The keywords: colorectal carcinoma, inflammation, Crohn disease, ulcerative colitis and inflammatory bowel disease were used. RESULTS: The nucleotide-binding oligomerization domain-containing protein 2 (NOD2) and toll like receptor (TLR) signaling pathways are clearly involved in the inflammatory process and are therefore implicated in the transformation of normal colonic mucosa to premalignant and malignant disease. Focal sites of inflammation could significantly increase the risk of initiation and development of cancer. Altered inflammatory activity is likely to be a result of either a disturbance of intestinal bacterial flora or an inadequate cellular response to it. Additionally, increasing the level of inflammation-related factors may also interfere with the control of cellular proliferation. CONCLUSIONS: This review shows an overview of the genetic and environmental factors that appear to influence both the occurrence of IBD and CRC with particular reference to NOD2 and TLRs as well as pro- and anti-inflammatory cytokines associated with tumor initiation and progression (encompassing both tumor invasion and metastases), as they constitute potential targets for therapeutic intervention.

Allosteric Modulation of Cannabinoid Receptor 1-Current Challenges and Future Opportunities.

The cannabinoid receptor type 1 (CB1R), a G protein-coupled receptor (GPCR), plays an essential role in the control of many physiological processes such as hunger, memory loss, gastrointestinal activity, catalepsy, fear, depression, and chronic pain. Therefore, it is an attractive target for drug discovery to manage pain, neurodegenerative disorders, obesity, and substance abuse. However, the psychoactive adverse effects, generated by CB1R activation in the brain, limit the use of the orthosteric CB1R ligands as drugs. The discovery of CB1R allosteric modulators during the last decade provided new tools to target the CB1R. Moreover, application of the site-directed mutagenesis in combination with advanced physical methods, especially X-ray crystallography and computational modeling, has opened new horizons for understanding the complexity of the structure, function, and activity of cannabinoid receptors. In this paper, we present the latest advances in research on the CB1R, its allosteric modulation and allosteric ligands, and their translational potential. We focused on structural essentials of the cannabinoid 1 receptor- ligand (drug) interactions, as well as modes of CB1R signaling regulation.

The c.470 T > C CHEK2 missense variant increases the risk of differentiated thyroid carcinoma in the Great Poland population.

BACKGROUND: Differentiated thyroid carcinoma (DTC) originates from thyroid follicular epithelial cells and belongs to a group of slowly progressing tumors with a relatively good prognosis. However, recurrences and metastases are a serious problem in advanced stages. Furthermore, progression from a well differentiated thyroid carcinoma to an aggressive anaplastic one is possible. The majority of differentiated thyroid carcinomas are sporadic but a few alleles increasing the cancer risk are known. One of them is the c.470 T > C (p.I157T, rs17879961) missense substitution in the CHEK2 gene. AIM OF THE STUDY: The aim of this study was to investigate whether this specific CHEK2 alteration, c.470 T > C, predisposes the Great Poland (Wielkopolska) population to thyroid cancer. METHODS: 602 differentiated thyroid carcinoma patients and 829 controls randomly selected from population were genotyped for the presence of the c.470C allele using pyrosequencing. Hardy-Weinberg Equilibrium (HWE) was tested for both groups by chi-square distribution and Fisher's exact test. The odds ratios (ORs), 95% confidence intervals (CIs), and p-values were calculated using the R software. RESULTS: The results of genotyping showed the presence of the c.470C allele in 51 patients with a frequency of 4.49%, while in a controls in 42 patients with a frequency of 2.53%. We demonstrated that in the Great Poland population the c.470C CHEK2 variant increases the risk of developing differentiated thyroid cancer almost twice (OR = 1.81, p = 0.004). The risk of papillary thyroid carcinoma in female patients homozygous for the c.470C allele was shown to increase almost 13-fold (OR = 12.81, p = 0.019). CONCLUSIONS: Identification of c.470C CHEK2 gene variant ought to be taken into account by healthcare policymakers. Future well-designed and larger population studies are of great value in confirming these findings. Moreover, a combination of genetic factors together with environmental exposures should also be considered.

From an understanding of etiopathogenesis to novel therapies-what is new in the treatment of celiac disease?

Celiac disease, a chronic autoimmune disorder caused by genetic factors and exposure to gluten, is increasingly being recognized and diagnosed in both children and adults. Scientists have been searching for a cure for this disease for many years, but despite the impressive development of knowledge in this field, a gluten-free diet remains the only recommended therapy for all patients. At the same time, the increasing diagnosis of celiac disease in adults, which was considered a childhood disease in the 20th century, has opened a discussion on the etiopathology of the disease, which is proven to be very complex and involves genetic, immunological, nutritional, environmental and gut microbiota-related factors. In this review, we extensively discuss these factors and summarize the knowledge of the proposed state-of-the-art treatments for celiac disease to address the question of whether a better understanding of the etiopathogenesis of celiac disease has opened new directions for therapy.