Screening for hereditary haemochromatosis in patients undergoing knee arthroplasty

Aims Hereditary haemochromatosis is a genetic disorder that is caused by several known mutations in the human homeostatic iron regulator protein ( HFE) gene. Abnormal accumulation of iron causes a joint disease that resembles osteoarthritis (OA), but appears at a relatively younger age and is accompanied by cirrhosis, diabetes, and injury to other organs. Increased serum transferrin saturation and ferritin levels are known markers of haemochromatosis with high positive predictive values. Methods We have retrospectively analyzed the iron studies of a cohort of 2,035 patients undergoing knee joint arthroplasty due to OA. Results No patients had HFE gene C282Y, S65C, or H63D mutations testing. In total, 18 patients (2.96%) of the male cohort and 51 (3.58%) of the female cohort had pathologically increased ferritin levels that may be indicative of haemochromatosis. Seven patients (0.34%) had serum transferrin saturation above 45%. Conclusion The awareness for the diagnosis of this disorder in Orthopaedics is low and needs improvement. Osteoarthritic patients undergoing knee arthroplasty should be routinely screened for haemochromatosis by iron studies and referred to genetic testing when needed. Level of evidence: Level III - Retrospective cohort study. Cite this article: Bone Jt Open 2021;2(12):1062–1066.

ALG1-CDG Caused by Non-functional Alternative Splicing Involving a Novel Pathogenic Complex Allele

This study reports on a Mexican mestizo patient with a multi-systemic syndrome including neurological involvement and a type I serum transferrin profile. Clinical exome sequencing revealed complex alleles in ALG1, the encoding gene for the chitobiosyldiphosphodolichol beta-mannosyltransferase that participates in the formation of the dolichol-pyrophosphate-GlcNAc2Man5, a lipid-linked glycan intermediate during N-glycan synthesis. The identified complex alleles were NM_019109.5(ALG1): c.[208 + 16_208 + 19dup; 208 + 25G > T] and NM_019109.5(ALG1): c.[208 + 16_208 + 19dup; 1312C > T]. Although both alleles carried the benign variant c.208 + 16_208 + 19dup, one allele carried a known ALG1 pathogenic variant (c.1312C > T), while the other carried a new uncharacterized variant (c.208 + 25G > T) causing non-functional alternative splicing that, in conjunction with the benign variant, defines the pathogenic protein effect (p.N70S_S71ins9). The presence in the patient’s serum of the pathognomonic N-linked mannose-deprived tetrasaccharide marker for ALG1-CDG (Neu5Acα2,6Galβ1,4-GlcNAcβ1,4GlcNAc) further supported this diagnosis. This is the first report of an ALG1-CDG patient from Latin America.

Reference Ranges of Iron Profiles in Apparently Healthy Elderly in Sokoto, Nigeria

Background: Iron is an important micronutrient in the body, lead to anaemia, frailty and cognitive disorders in the elderly when deficient. Aim: This study was aimed to determine reference values of iron profile in apparently healthy elderly persons in Sokoto and compared with the local reference values. Study Design: This was a comparative study Duration of Study: The study lasted for a period of one year between January to December, 2020. Methodology: This was a comparative study involving 105 apparently healthy elderly persons aged 60 years and above in Sokoto metropolis. Serum iron and total-iron binding capacity (TIBC) were determined using Iron Ferrozine method. Serum ferritin, Serum transferrin (Tf) and Serum Transferrin Receptors (sTfR) were assayed using enzyme-linked immunosorbent assay (ELISA). Transferrin Saturation (TS) and Serum Transferrin Receptors ferritin log (sTfR/FL) was calculated. Data were expressed as percentiles, mean and standard deviation and analysed using t-test and one way ANOVA. Results: The study established reference ranges of Serum iron,TIBC, Serum ferritin, Tf, sTfR, TS and sTfR/FL was calculated. in Sokoto. The study showed that iron and ferritin have high reference ranges than the local values in Sokoto. The local values for TIBC, ferritin, sTfR, TS and sTfR/FL were not available. Mean Ferritin (µg/L), sTfR (ng/L) and sTfR/Fl the test subjects were significantly higher in males than females in Sokoto (p=0.026), (p= 0.001), (p=0.044) and (p= 0.003) respectively. Iron, ferritin and TS increased as the BMI was increasing (p=<0.001). Conclusion: In conclusion, normal reference values obtained in this study notably vary with the local reference ranges used in the Sokoto metropolis. There is a need for each locality to have separate reference ranges for the elderly for their proper diagnosis and management of iron related disorders.

Interactions of Chemically Synthesized Ferrihydrite Nanoparticles with Human Serum Transferrin: Insights from Fluorescence Spectroscopic Studies

Human serum transferrin (HST) is a glycoprotein involved in iron transport that may be a candidate for functionalized nanoparticles to bind and target cancer cells. In this study, the effects of the simple and doped with cobalt (Co) and copper (Cu) ferrihydrite nanoparticles (Fh-NPs, Cu-Fh-NPs, and Co-Fh-NPs) were studied by spectroscopic and molecular approaches. Fluorescence spectroscopy revealed a static quenching mechanism for all three types of Fh-NPs. All Fh-NPs interacted with HST with low affinity, and the binding was driven by hydrogen bonding and van der Waals forces for simple Fh-NPs and by hydrophobic interactions for Cu-Fh-NPs and Co-Fh-NPs binding, respectively. Of all samples, simple Fh-NPs bound the most to the HST binding site. Fluorescence resonance energy transfer (FRET) allowed the efficient determination of the energy transfer between HST and NPs and the distance at which the transfer takes place and confirmed the mechanism of quenching. The denaturation of the HST is an endothermic process, both in the case of apo HST and HST in the presence of the three types of Fh-NPs. Molecular docking studies revealed that Fh binds with a low affinity to HST (Ka = 9.17 × 103 M−1) in accord with the fluorescence results, where the interaction between simple Fh-NPs and HST was described by a binding constant of 9.54 × 103 M−1.

The Role of Transferrin and Laminin Biomarkers in the Diagnosis of Diabetic Nephropathy in Type II Diabetic Patients

Background/Aim: Diabetic nephropathy is one of the most important microvascular complications associated with type II diabetic patients. It occurs in 20-40% patients with diabetes mellitus, and microalbuminuria is still considered as the first sign of diabetic nephropathy. Low sensitivity and specificity of microalbuminuria leads to more sensitive biomarkers that may be used to detect diabetic nephropathy at an earlier stage with higher accuracy. This study was carried out to detect the validity of using serum Transferrin and Laminin as a diagnostic biomarkers for diabetic nephropathy in type ΙΙ diabetic patients. Methods: Egyptian patients (n=96) included 72 type 2 diabetic patients who were classified into three groups: group 1 - normoalbuminuric patients (uACR up to 30 mg/g), group 2 - microalbuminuric patients (uACR from 30 – 300 mg/g), group 3 - macroalbuminuric patients (uACR from >300 mg/g) and 24 healthy control were surveyed in a cross-sectional study over a period of 6 months at biochemistry department, KASR ALAINY Hospital of Cairo University. Patients were subjected to measurement of Albumin creatinine ratio, eGFR, Serum creatinine, glycosylated hemoglobin (HbA1c) and lipid profile. The serum concentrations of transferrin and lamnin were measured using a highly sensitive one-step sandwich enzyme immunoassay kit. Results: Serum laminin was significantly higher in macroalbuminuric patients than in the microalbuminuric and in microalbuminuric patients than in the normoalbuminuric and healthy control subject. By comparing these goups according to serum laminin concentration we found statistically significant positive correlation (p value <0.001, r= 0.670), serum transferrin was significantly lower in macroalbuminuric patients than in the microalbuminuric and in microalbuminuric patients than in the normoalbuminuric and healthy control subject. By comparing these goups according to serum transferrin concentration we found statistically significant inverse correlation (p value <0.001, r= -0.579). There was no correlation between level of serum transferrin /laminin and glycoregulation, and statistically significant positive correlation was found between serum laminin and duration of diabetes and statistically significant inverse correlation was found between serum transferrin and duration of diabetes. Conclusions: The results from this study provide the evidence that serum laminin and transferrin could be used as a diagnostic markers of diabetic nephropathy.

Serum transferrin as a biomarker of hepatocyte nuclear factor 4 alpha activity and hepatocyte function in liver diseases

Background Serum transferrin levels represent an independent predictor of mortality in patients with liver failure. Hepatocyte nuclear factor 4 alpha (HNF4α) is a master regulator of hepatocyte functions. The aim of this study was to explore whether serum transferrin reflects HNF4α activity. Methods Factors regulating transferrin expression in alcoholic hepatitis (AH) were assessed via transcriptomic/methylomic analysis as well as chromatin immunoprecipitation coupled to DNA sequencing. The findings were corroborated in primary hepatocytes. Serum and liver samples from 40 patients with advanced liver disease of multiple etiologies were also studied. Results In patients with advanced liver disease, serum transferrin levels correlated with hepatic transferrin expression (r = 0.51, p = 0.01). Immunohistochemical and biochemical tests confirmed reduced HNF4α and transferrin protein levels in individuals with cirrhosis. In AH, hepatic gene-gene correlation analysis in liver transcriptome revealed an enrichment of HNF4α signature in transferrin-correlated transcriptome while transforming growth factor beta 1 (TGFβ1), tumor necrosis factor α (TNFα), interleukin 1 beta (IL-1β), and interleukin 6 (IL-6) negatively associated with transferrin signature. A key regulatory region in transferrin promoter was hypermethylated in patients with AH. In primary hepatocytes, treatment with TGFβ1 or the HNF4α inhibitor BI6015 suppressed transferrin production, while exposure to TNFα, IL-1β, and IL-6 had no effect. The correlation between hepatic HNF4A and transferrin mRNA levels was also seen in advanced liver disease. Conclusions Serum transferrin levels constitute a prognostic and mechanistic biomarker. Consequently, they may serve as a surrogate of impaired hepatic HNF4α signaling and liver failure.