The multi-systemic nature of diabetes mellitus: Genotype or phenotype?

Impact of the -1T>C single-nucleotide polymorphism of the CD40 gene on the development of endothelial dysfunction in a pro-diabetic microenvironment

BACKGROUND AND AIMS

Hyperglycemia reinforces pro-inflammatory conditions that enhance CD40 expression in endothelial cells (EC). Thymine to cytosine transition (-1T > C) in the promoter of the CD40 gene (rs1883832) further increases the abundance of CD40 protein on the EC surface. This study examines potential associations of the -1T > C SNP of the CD40 gene with type 1 (T1D) or type 2 (T2D) diabetes. Moreover, it investigates the impact of a pro-inflammatory diabetic microenvironment on gene expression in human cultured umbilical vein EC (HUVEC) derived from CC- vs. TT-genotype donors.

METHODS

Tetra-ARMS-PCR was used to compare genotype distribution in 252 patients with diabetes. Soluble CD40 ligand (sCD40L) and soluble CD40 receptor (sCD40) plasma levels were monitored using ELISA. RNA-sequencing was performed with sCD40L-stimulated CC- and TT-genotype HUVEC. Quantitative PCR, Western blot, multiplex-sandwich ELISA array, and immunocytochemistry were used to analyse changes in gene expression in these cells.

RESULTS

Homozygosity for the C-allele was associated with a significant 4.3-fold higher odds of developing T2D as compared to individuals homozygous for the T-allele. Inflammation and endothelial-to-mesenchymal transition (EndMT) driving genes were upregulated in CC-genotype but downregulated in TT-genotype HUVEC when exposed to sCD40L. Expression of EndMT markers significantly increased while that of endothelial markers decreased in HUVEC following exposure to hyperglycemia, tumour necrosis factor-α and sCD40L.

CONCLUSIONS

The -1T > C SNP of the CD40 gene is a risk factor for T2D. Depending on the genotype, it differentially affects gene expression in human cultured EC. CC-genotype HUVEC adopt a pro-inflammatory and intermediate EndMT-like phenotype in a pro-diabetic microenvironment.

Micronuclei, inflammation and auto-immune disease

Auto-immune diseases (AUD) are characterized by an immune response to antigenic components of the host itself. The etiology of AUD is not well understood. The available evidence points to an interaction between genetic, epigenetic, environmental, infectious and life-style factors. AUD are more prevalent in women than in men; sex hormones play a crucial role in this sex bias. Micronuclei (MN) emerged as a new player in the induction of AUD, based on the capacity of DNA-sensors to detect self-DNA that leaks into the cytoplasm from disrupted MN and induce the cGAS-STING pathway triggering an innate auto-immune response and chronic inflammation. It was found that inflammation can induce MN and MN can induce inflammation, leading to a vicious inflammation-oxidative-DNA damage-MN-formation-chromothripsis cycle. MN originating from sex chromosome-loss may induce inflammation and AUD. We performed a systematic review of studies reporting MN in patients with systemic or organ-specific AUD. A meta-analysis was performed on lymphocyte MN in diabetes mellitus (10 studies, 457 patients/290 controls) and Behcet's disease (3 studies, 100 patients/70 controls) and for buccal MN in diabetes mellitus (11 studies, 507 patients/427 controls). A statistically significant increase in patients compared to controls was found in the meta-analyses providing an indication of an association between MN and AUD. A 36%-higher mean-MRi in buccal cells (3.8+/-0.7) was found compared to lymphocytes (2.8+/-0.7)(P = 0.01). The meta-MRi in lymphocytes and buccal cells (1.7 and 3.0 respectively) suggest that buccal cells may be more sensitive. To assess their relative sensitivity, studies with measurements from the same subjects would be desirable. It is important that future studies (i) investigate, in well-designed powered studies, the prospective association of MN-formation with AUD and (ii) explore the molecular mechanisms by which chromosome shattering in MN and the release of chromatin fragments from MN lead to the formation of auto-antibodies.

Evolution and etiopathogenesis of bisphosphonates induced osteonecrosis of the jaw

Bisphosphonates (BPs) is widely used as the first line of treatment choice for osteoporosis, Paget’s disease of bone, bone cancer metastasis and hypercalcemia of malignancy. BPs induced osteonecrosis of the jaw (ONJ) is a relatively rare but severe clinical condition cited in English literature since 2003 while exact pathogenesis of BPs induced ONJ is not known until today, but numerous hypotheses were described in recent literature that promote and interlinked the development of BPs induced ONJ. These hypotheses indicate multifactorial nature of its development and factors responsible for that are; long term administration of intravenous nitrogen containing BPs in cancer patients, biological behavior of jaw, antiangiogenic property of BPs and by soft-tissue toxicity etc., All these factors are compounded by the presence of infection that are responsible for lower the pH of the oral cavity, other drugs like administration of corticosteroid, pathologies that cause hypo-calcification of bone, compromised immune response that alters normal healing such as renal transplantation followed by long term oral BPs therapy or chronic diabetic patients receiving BPs therapy and any dentoalveolar trauma. All literature in this review article is search from PubMed, Med-know and Google search engines.

Fashion or Science? How Can Orthodox Biomedicine Explain the Body's Function and Regulation?

The cost of diagnosing and treating disease continues to rise inexorably. Almost every new test adds to the complexity and cost of healthcare. There is a need for better and less expensive screening, diagnostic and scanning techniques. Medical scanning technologies are based upon the body's response to an external stimulus e.g. heat, ultrasound, X-rays, magnetic resonance, etc. Biomarker and histopathology tests have inherent limitations because diseases are often polygenic and/or influence the function of multiple physiological systems. The results are compared with expected norms. This makes it difficult to diagnose the onset of disease. Such techniques measure only what the clinician wants or expects to see. A technique which can provide more information, regarding the influence of a medical condition upon the body's whole function, may be invaluable to the clinician. There is not yet a clear understanding of how the body regulates its function. A greater understanding of how the body responds to sensory input, in particular to light, has been incorporated into a mathematical model of the physiological systems developed by I.G. Grakov. This has been incorporated into a cognitive technology which improves the understanding of how the body regulates its function and has led to the development of a better method for the diagnosis and treatment of disease(s). This technique, virtual scanning, appears able to diagnose at different levels of physiological significance i.e. as systems, organs, cells (as morphologies) and molecular (as pathologies). It may be a major scientific development, conceivably more advanced than biomarker techniques, with the potential to provide far more information about a patient's health. It may have the potential to significantly reduce the complexity and cost of healthcare. This article reviews the available literature.