Intracellular magnesium content changes during mitochondria-mediated apoptosis: in depth study of early events on mitochondrial membrane potential

A recent study showed the antitumor activity of a new indole-derivative – MM-67 – inducing mitochondria-mediated apoptosis and a decrease of intracellular magnesium (Mg) concentration in HT29 colon cancer cells. Aim of this work was to assess cellular Mg levels throughout MM-67-induced apoptosis from the early to the final stage of the process and to evaluate the correlation with mitochondrial membrane potential (ΔΨm) variations. All analysis were performed by flow cytometry: ΔΨm was assessed by using mitochondrial potential sensitive dye DiOC6, while free and total intracellular cation concentrations were assessed by using the commercial probe MagFluo4-AM (Kd=4.7 mM), and the new synthesized DCHQ5 (Kd=8.3 mM), respectively. Our results evidenced that the MM67 induced apoptosis is characterized by a direct correlation between ΔΨ and free intracellular Mg content variations

The Role of CD1 Gene Polymorphism in the Genetic Susceptibility to Spondyloarthropathies in the Moroccan Population and the Possible Cross-Link with Celiac Disease

Spondyloarthropathies (SpA) are a group of chronic inflammatory disorders usually affecting the axial spine and asymmetrical peripheral joints. Strong evidence links genetic and environmental factors to SpA pathogenesis. The HLA-B27 is the most important genetic factor associated with SpA. Nevertheless, the involvement of other HLA and non-HLA loci has been also reported. Some patients with SpA may also manifest features of celiac disease (CeD), thus suggesting a genetic overlap across these autoimmune diseases. Recently, CD1 glycoproteins, a class of molecules able to bind and present non peptidic antigens to T cells, aroused interest for their contribution to the pathogenesis of CeD. Therefore, to evaluate whether functional polymorphisms of CD1A and E genes also influence susceptibility to SpA, we analyzed 86 patients from Morocco affected by SpA and 51 healthy controls, using direct sequencing analysis. An increase of CD1E*01/01 homozygous genotype (p = 0.046) was found in SpA, compared with controls. CD1E*01/01 genotype was associated particularly to patients with sacroiliac joints/spine/peripheral joints pain (p = 0.0068), while a decrease of CD1E*01/02 genotype was evidenced compared to controls (p = 0.0065). Results from haplotypes analysis demonstrated that CD1A*02-E*02 decreased the risk of SpA, while CD1A*02-E*01 increased risk to develop disease. Our data indicate a relationship between CD1 genes and susceptibility to SpA in the Moroccan population and suggest the existence of shared genetic risk loci across SpA and CeD that might be useful to explain common pathogenetic features and define novel therapeutic strategies

The Role of CD1 Gene Polymorphism in the Genetic Susceptibility to Spondyloarthropathies in the Moroccan Population and the Possible Cross-Link with Celiac Disease

Spondyloarthropathies (SpA) are a group of chronic inflammatory disorders usually affecting the axial spine and asymmetrical peripheral joints. Strong evidence links genetic and environmental factors to SpA pathogenesis. The HLA-B27 is the most important genetic factor associated with SpA. Nevertheless, the involvement of other HLA and non-HLA loci has been also reported. Some patients with SpA may also manifest features of celiac disease (CeD), thus suggesting a genetic overlap across these autoimmune diseases. Recently, CD1 glycoproteins, a class of molecules able to bind and present non peptidic antigens to T cells, aroused interest for their contribution to the pathogenesis of CeD. Therefore, to evaluate whether functional polymorphisms of CD1A and E genes also influence susceptibility to SpA, we analyzed 86 patients from Morocco affected by SpA and 51 healthy controls, using direct sequencing analysis. An increase of CD1E*01/01 homozygous genotype (p = 0.046) was found in SpA, compared with controls. CD1E*01/01 genotype was associated particularly to patients with sacroiliac joints/spine/peripheral joints pain (p = 0.0068), while a decrease of CD1E*01/02 genotype was evidenced compared to controls (p = 0.0065). Results from haplotypes analysis demonstrated that CD1A*02-E*02 decreased the risk of SpA, while CD1A*02-E*01 increased risk to develop disease. Our data indicate a relationship between CD1 genes and susceptibility to SpA in the Moroccan population and suggest the existence of shared genetic risk loci across SpA and CeD that might be useful to explain common pathogenetic features and define novel therapeutic strategies

Intracellular magnesium content changes during mitochondria-mediated apoptosis: in depth study of early events on mitochondrial membrane potential

A recent study showed the antitumor activity of a new indole-derivative – MM-67 – inducing mitochondria-mediated apoptosis and a decrease of intracellular magnesium (Mg) concentration in HT29 colon cancer cells. Aim of this work was to assess cellular Mg levels throughout MM-67-induced apoptosis from the early to the final stage of the process and to evaluate the correlation with mitochondrial membrane potential (ΔΨm) variations. All analysis were performed by flow cytometry: ΔΨm was assessed by using mitochondrial potential sensitive dye DiOC6, while free and total intracellular cation concentrations were assessed by using the commercial probe MagFluo4-AM (Kd=4.7 mM), and the new synthesized DCHQ5 (Kd=8.3 mM), respectively. Our results evidenced that the MM67 induced apoptosis is characterized by a direct correlation between ΔΨ and free intracellular Mg content variations

HLA Typing and Celiac Disease in Moroccans

Genetic and environmental factors are responsible for differences in the prevalence of some diseases across countries. Human leukocyte antigen (HLA) allele frequencies in North African populations show some differences in their distribution compared to Europeans, Mediterraneans, and sub-Saharans, and some specific alleles and haplotypes could be clinically relevant. Celiac disease (CD) has been fast increasing in prevalence in North Africa; but few immunogenetic data are available for this area, in which a high prevalence of the disease has been described. In this report, we assess and discuss results of HLA class II (HLA-DQA1/DQB1/DRB1) typing in Moroccan patients with CD and compare them with a control population from Morocco—genetically well characterized—and with other North African, Mediterranean, and European populations. The classical HLA-DQ associations were confirmed in Moroccans with CD. The high frequency of DQ2.5 homozygosity (45.2%) found in Moroccans with CD was noteworthy as compared with other populations (23%–32%). The genetic risk gradient for CD, identified by previous studies, has been confirmed in Moroccans with some differences, mainly concerning DQ8 genotypes. This study provides the immunogenetic framework of CD in Moroccans and confirms the need to learn more about associations with additional HLA and non-HLA genetic factors

HLA-G14bp ins/del polymorphism and post-transplant weight gain in kidney transplantation: potential implications beyond tolerance.

Human leukocyte antigen (HLA)-G is a non-classical HLA molecule with immunomodulant and immunosuppressive functions, involved in transplantation tolerance. HLA-G14bp ins/del polymorphism in exon 8 has been associated with allograft rejection and kidney transplant outcome, with controversial results. We investigated associations of HLA-G14bp ins/del polymorphism on onset of some of the main post-transplant risk factors, like excess body weight, lipid abnormalities, increased fasting plasma glucose. Polymorphisms of cytokines with both immunosuppressive and metabolic effects were also assessed for comparisons and associated analysis. The present study involved kidney transplant recipients (n = 173) in which body mass index, cholesterol, triglycerides, fasting plasma glucose were registered in the first years after transplantation and analyzed in association with genotypes. Presence of hypertension and smoking habits, demographic, transplant-related and therapeutic data of patients were also recorded. Polymerase chain reaction, sequence-specific primer amplification and Taqman allelic discrimination techniques were used for genotyping of HLA-G14bp ins/del, interleukin (IL)-10(-1082G > A,-819 T > C,-592A > C), transforming growth factor-β(+ 869 T > C,+915C > G), IL-6(-174G > C), tumor necrosis factor-α(-308G > A) and IL-18(-137G > C,-607C > A). Effects of genotypes on clinical markers at each time point (pre-transplant and 1 to 5 years after transplant) were analyzed using a repeated-measures general linear model analysis; adjustment for potential confounders was performed. Results showed that HLA-G14bp ins/ins was significantly associated with obesity, in particular after transplantation (3 years, p = 0.002, OR = 4.48, 95% CI:1.76-11.41). Post-transplant body mass index was significantly increased in HLA-G14bp ins/ins carriers (3 and 4 years, p = 0.033 and p = 0.044); effects of HLA-G14bp genotypes on post-transplant BMI were confirmed by using repeated-measures analysis and after controlling for confounding variables. Cytokine genotypes did not associate with the examined factors. The study of transplanted patients allowed to evidence a potential relationship between post-transplant weight gain and HLA-G14bp ins/del polymorphism, previously involved in rejection for its immunosuppressive/tolerogenic activity. This novel association could widen the knowledge of the role and functions of HLA-G molecules in diseases and transplantation

Evaluation of Plasma Levels of Soluble HLA-G and HLA-G Genotypes in Kidney Transplant Recipients.

In the field of transplantation, expression of HLA-G, a nonclassical HLA molecule with immunosuppressive functions and limited gene polymorphism, is considered beneficial for graft acceptance; various studies have aimed to demonstrate this role in transplantation. Recently, in other clinical conditions, it has been observed that insulin resistance was associated with HLA-G14bpins/del polymorphism, the most studied regulatory polymorphism of this molecule. In the present study, plasma levels of the soluble form of HLA-G (sHLA-G) were analyzed in kidney transplant recipients (n = 103) with different HLA-G14bpins/del genotypes. In a group of 26 recipients, sHLA-G was detected before and after transplantation (1 year) to evaluate early variations. In 77 recipients, sHLA-G was detected after transplantation (3-24 years) and correlated with occurrence of long-term post-transplant morbidity (diabetes mellitus, hyperlipidemia, hypertension, obesity, etc.). Levels of sHLA-G were measured in plasma with an enzyme-linked immunosorbent assay; HLA-G14bpins/del and HLA-G+3142C>G genotypes were assessed using direct polymerase chain reaction. Plasma levels of sHLA-G significantly decreased during the first year after transplantation (P = .019); no significant correlations were found with genotypes or early post-transplant events. Lower levels of sHLA-G were found in recipients with post-transplant diabetes mellitus or obesity carrying the HLA-G14bpins/ins (P = .006 and P = .003, respectively) or HLA-G+3142G/G genotypes. A complex modulation of HLA-G, which includes both immunologic and metabolic effects, could affect the risk for long-term post-transplant morbidity in kidney transplant recipients. Associations of HLA-G, diabetes, and obesity deserve to be investigated by deeply exploring HLA-G regulatory variants

Gene- and Gender-Related Decrease in Serum BDNF Levels in Alzheimer’s Disease

Brain-derived neurotrophic factor (BDNF) has a protective role in Alzheimer’s disease (AD). Oxidative stress and inflammatory cytokines are potentially implicated in AD risk. In this study, BDNF was detected in serum of AD and mild cognitive impairment (MCI) patients and investigated in association with gene polymorphisms of BDNF (Val66Met and C270T), of some oxidative stress-related genes (FOXO3A, SIRT3, GLO1, and SOD2), and of interleukin-1 family genes (IL-1α, IL-1β, and IL-38). The APOE status and mini-mental state examination (MMSE) score were also evaluated. Serum BDNF was significantly lower in AD (p = 0.029), especially when comparing the female subsets (p = 0.005). Patients with BDNFVal/Val homozygous also had significantly lower circulating BDNF compared with controls (p = 0.010). Moreover, lower BDNF was associated with the presence of the T mutant allele of IL-1α(rs1800587) in AD (p = 0.040). These results were even more significant in the female subsets (BDNFVal/Val, p = 0.001; IL-1α, p = 0.013; males: ns). In conclusion, reduced serum levels of BDNF were found in AD; polymorphisms of the IL-1α and BDNF genes appear to be involved in changes in serum BDNF, particularly in female patients, while no effects of other gene variants affecting oxidative stress have been found. These findings add another step in identifying gender-related susceptibility to AD