International journal of biochemistry and molecular biology最新文献

Background: Cancer chemotherapy with doxorubicin (DOX) has been linked to serious testicular damage and spermatotoxicity due to the induction of oxidative stress, inflammation, and apoptosis. Thus, the current study was carried out to assess the potential ameliorative impact of diosmin, an antioxidant drug, against DOX-mediated spermatoxicity and testicular injury in rats.

Material and methods: In the experimental protocol, rats were grouped into 4: Group 1 received vehicle and saline for 8 weeks while group 2 received diosmin and saline concomitantly for 8 weeks. Group 3 was given 3 mg/kg intraperitoneal DOX once every 7 days for 8 weeks. Group 4 was given 40 mg/kg of diosmin orally for 56 days followed by DOX diosmin administration after one hour. After 56 days of treatment, sperm quality, hormonal testing, biochemical parameters, and histological alterations in the testes were evaluated.

Results: DOX-induced reduce spermatogenic function, testicular 3- and 17β-Hydroxysteroid dehydrogenases, and serum follicle stimulating hormone, luteinizing hormone, and testosterone. It also enhanced inflammation, testicular oxidative damage, and apoptosis. The histopathologic examinations corroborated the biochemical results obtained. Significantly, diosmin treatment reduced DOX-induced injury, as evidenced by restored testicular architecture, increased steroidogenesis, preservation of spermatogenesis, suppression of oxide-inflammatory response, and apoptosis.

Conclusion: It was found that through diosmin antioxidant, anti-apoptotic, and anti-oxido-inflammatory it presents a possible therapeutic alternative for protecting testicular tissue against DOX's harmful effects.

Introduction: Glomerular podocytes are specialized epithelial cells localized to the blood-urine interface of the kidney. Podocyte slit-diaphragm (SD), a size-and-charge-selective junction, is instrumental in blood ultrafiltration and the formation of protein-free urine. The SD consists of macromolecular complexes of several proteins, such as nephrin, podocin, and CD2-associated protein (CD2AP). CD2AP is an adapter protein and is considered to be crucial for the integrity of SD. Mutations in the SD proteins cause nephrotic syndrome (NS), characterized by proteinuria. SD proteins' structural features must be elucidated to understand the mechanism of proteinuria in NS. In this study, we expressed, purified, and biophysically characterized heterologously expressed human CD2AP.

Methods: Codon-optimized human CD2AP was expressed in E. coli Rosetta cells. The recombinant protein was induced with 1 mM IPTG and purified by Ni-NTA affinity chromatography. Analytical size-exclusion chromatography, blue native-PAGE, circular dichroism, and fluorescence spectroscopy were performed to decipher the oligomeric nature, secondary structural content, and tertiary packing of CD2AP.

Results: Our analysis revealed that CD2AP adopts a predominantly disordered secondary structure despite exhibiting moderate tertiary packing, characterized by low helical and β-sheet content. CD2AP readily assembles into homo-oligomers, with octamers and tetramers constituting the primary population. Interestingly, the inherent flexibility of CD2AP's secondary structural elements appears resistant to thermal denaturation. Frameshift mutation (p.K579Efs*7) that leads to loss of the coiled-coil domain promotes aberrant oligomerization of CD2AP through SH3 domains.

Conclusion: We successfully expressed full-length human CD2AP in a heterologous system, wherein the secondary structure of CD2AP is predominantly disordered. CD2AP can form higher-order oligomers, and the significance of these oligomers and the impact of mutations in the context of size-selective permeability of SD needs further investigation.

Background: Diabetic nephropathy (DN) is a prevalent and chronic, severe complication of diabetes, representing a serious global health concern. Early detection of DN is essential for initiating timely and effective therapeutic interventions and accurately assessing prognosis. Neutrophil Gelatinase-Associated Lipocalin (NGAL), a low molecular weight protein, has emerged as a potential biomarker for DN due to its association with renal injury and its ability to provide early indications of kidney damage. NGAL levels in both serum and urine are elevated in individuals with renal damage, making it a valuable biomarker for detecting early signs of kidney impairment in the context of diabetes. This study aims to investigate the utility of NGAL as an early biomarker for DN and explore its correlation with various clinical parameters associated with the disease. Understanding the relationship between NGAL levels and clinical parameters such as glycemic control, renal function, blood pressure, and duration of diabetes is crucial for comprehensively evaluating the potential of NGAL as a diagnostic and prognostic tool for DN. Furthermore, assessing the sensitivity and specificity of NGAL in detecting early-stage DN will provide valuable insights into its clinical applicability and reliability.

Methodology: A planned meta-analysis was conducted following PRISMA and MOOSE guidelines. The PubMed database was searched from January 2016 to June 2023 for English-language studies on DN and NGAL. Fifteen eligible studies were included as per the criteria. Data on serum NGAL levels in DN patients and healthy controls were analyzed using Stata 16.0 software.

Result: The study revealed a significantly higher mean serum NGAL level in DN patients (168.08 ng/ml, 95% CI: 105.50-230.67) compared to healthy controls (75.02 ng/ml, 95% CI: 43.02-107.03), demonstrating NGAL's potential as a biomarker (P=0.01).

Conclusion: NGAL offers a powerful tool for DN diagnosis, staging, and monitoring, surpassing traditional markers in sensitivity. Challenges include defining universal threshold values and ensuring consistent test performance across diverse clinical settings. The study underscores NGAL's potential in transforming DN diagnosis and management.

Objectives: Accumulative effects of heavy metals and polycyclic aromatic hydrocarbon could result in various toxicities. This study evaluated the effects of long-term exposure to low doses of nickel and benzo [a] anthracene on the kidney of rats, simulating human exposure through food.

Methods: Thirty-six (36) Male rats weighing between 80-100 g were assigned into six groups of 6 animals each; Group A (normal), Group B1 and B2 (fed nickel contaminated feed for 12 and 24 weeks), Group C1 and C2 (fed benzo [a] anthracene contaminated feed for 12 and 24 weeks). Blood and kidney of the rats were harvested after animal sacrifice. Serum creatinine and urea concentration and renal Superoxide Dismutase (SOD) activity, GSH, MDA, protein carbonyl, and total protein concentration by spectrophotometric methods. While the concentration of 8-oxodeoxyguanosine in kidney was determined by ELISA method and protein carbonyl by colorimetric method. Renal histological analysis was done with H and E staining. Statistical analysis was performed with Statistical Package for Social Sciences (SPSS) and statistical significance was accepted 95 percent confidence level.

Result: From the results, urea concentration increased significantly (P<0.05) in the nickel exposed group after 24 weeks exposure whereas creatinine concentration increased significantly (P<0.05) after 12 weeks of exposure when compared with the control. Comparison of the serum urea and creatinine level of the benzo [a] anthracene exposed group with the control showed no significant (P>0.05) difference. Histological observations indicate glomerular atrophy and widened capsular space haemorrhagic areas, visceral and parietal layer of the Bowman's capsule, the proximal convoluted tubule in the nickel exposed group while the kidney of benzo (a) anthracene exposed rats showed deviation in the histo-architecture of the renal parenchyma as evidenced by glomerular atrophy and widened Bowman's capsular space and focal haemorrhagic areas. Protein thiol level and Superoxide dismutase activity was significantly (P<0.05) depleted in the benzo [a] anthracene exposed groups. The levels of total protein, protein carbonyl, and 8-oxodeoxyguanosine were significantly (P<0.05) elevated in the nickel and benzo [a] anthracene exposed groups.

Conclusion: This study demonstrated the oxidative stress causing effects of benzo [a] anthracene and nickel in the kidney. It also shows that consistent exposure to low doses of the contaminants for a lifetime might result in renal oxidative stress with consequential loss of renal function.

Objectives: Jumonji C domain-containing (JMJD) 2B (JMJD2B) is a transcriptional cofactor and histone demethylase that is involved in prostate cancer formation. However, how its function is regulated by posttranslational modification has remained elusive. Hence, we examined if JMJD2B would be regulated by lysine methylation.

Methods: Through in vitro methylation assays and Western blotting with methyl-lysine specific antibodies, we analyzed lysine methylation within JMJD2B. Identified methylated lysine residues were mutated to arginine residues and the respective impact on JMJD2B transcriptional activity measured with a reporter gene assay in human LNCaP prostate cancer cells.

Results: We discovered that JMJD2B is methylated on up to six different lysine residues. Further, we identified the suppressor of variegation 3-9/enhancer of zeste/trithorax (SET) domain-containing protein 7/9 (SET7/9) as the methyltransferase being responsible for this posttranslational modification. Mutating the methylation sites in JMJD2B to arginine residues led to diminished coactivation of the Ju-nana (JUN) transcription factor, which is a known oncogenic protein in prostate tumors. In contrast, methylation of JMJD2B had no impact on its ability to coactivate another transcription factor associated with prostate cancer, the DNA-binding protein E26 transformation-specific (ETS) variant 1 (ETV1). Consistent with a potential joint action of JMJD2B, SET7/9 and JUN in prostate cancer, the expression of JMJD2B in human prostate tumors was positively correlated with both SET7/9 and JUN levels.

Conclusions: The identified SET7/9-mediated methylation of JMJD2B appears to impact its cooperation with selected interacting transcription factors in prostate cancer cells. Given the implicated roles of JMJD2B beyond prostate tumorigenesis, SET7/9-mediated methylation of JMJD2B possibly also influences the development of other cancers, while its impairment might have relevance for obesity or a global developmental delay that can be elicited by reduced JMJD2B activity.

Background: Phospholipids are highly diverse molecules with pleiotropic biological roles, from membrane components and signaling molecules, whose composition can change in response to both endogenous and external stimuli. Recent lipidomic studies on edible bivalve mollusks were focused on lipid nutritional value and growth requirements. However, no data are available on phospholipid profiles during bivalve larval development. In the model marine bivalve Mytilus galloprovincialis, early larvae (up to 48 hours post fertilization-hpf) undergo dramatic molecular and functional changes, including shell biogenesis and neurogenesis, that are sustained by egg lipid reserves. Changes in phospholipid composition may also occur participating in the complex processes of early development.

Objective: The lipidome of M. galloprovincialis eggs and early larval stages (24 and 48 hpf) was investigated in order to identify possible changes in phospholipid classes and related metabolic pathways that may play a role in key steps of development.

Materials and methods: Lipidomic analysis were performed by NMR spectroscopy and liquid chromatography-mass spectrometry (LC-MS), with focus on phospholipids. Shifts in relative species composition of phosphatidylcholine, phosphatidylethanolamine, plasmalogen, and ceramide aminoethylphosphonate-CAEP, the bivalve analogue of the main mammalian ceramide sphingomyelin, were observed. Expression of genes involved in ceramide homeostasis was also modulated from eggs to early larval stages.

Results: The results represent the first data on changes in phospholipid composition in bivalve larvae and suggest a functional role of phospholipids in mussel early development.

Conclusion: The results underline the importance of lipidomic studies in bivalve larvae, in both physiological conditions and in response to environmental stress.

Background: The diverse nature of carbohydrate structures and linkages requires a variety of enzymes responsible for sugar degradation. The E. coli periplasmic protein encoded by the bglX gene has been assigned to glycoside hydrolase family 3 and is predicted to function as a β-glucosidase.

Objectives: We investigated the catalytic properties of the E. coli protein BglX and identified two functionally important amino acid residues.

Methods: The bglX gene was cloned into a pET20b(+) vector, and three mutants, D111N, D287G, and E293Q, were generated using site-directed mutagenesis. Kinetic studies were performed on the wild-type and mutant enzymes.

Results: Substrate specificity tests indicated that the BglX enzyme hydrolyzes β-glycosidic bonds in nitrophenyl-β-glycosides and demonstrates greater activity towards galactose-containing substrates compared to glucose derivatives. Monomeric glucose and galactose inhibit enzyme activity to a different degree in a substrate-dependent manner. In addition, BglX can hydrolyze lactose but not cellobiose, maltose, or laminarin. Subsequently, E. coli cells overexpressing active BglX have a growth advantage on minimal media supplemented with lactose as a carbon source. Mutation of D287 or D111 residues negatively affected the activity of BglX indicating their involvement in catalysis. Overexpression of BglX by E. coli cells did not increase biofilm formation.

Conclusions: The low activity towards glucose-containing substrates and significantly elevated activity towards galactosides suggests that β-glucosidase activity may not be the primary function of the BglX enzyme.

Background: There is insufficient data on the prevalence and consequences of eating disorders in Type 2 diabetic patients.

Objective: To evaluate the presence of eating disorders (ED) and their association with glycaemic control and metabolic parameters in adult patients with type 2 diabetes mellitus (T2DM).

Materials and methods: A cross-sectional study on 145 patients was conducted in the medicine outpatient unit of HAHC Hospital, Jamia Hamdard tertiary care center. The Eating Attitudes Test (EAT-26) was used to screen for ED in adults with T2DM. The Score of less than 20 and more than 30 on EAT-26 questionnaire was defined as control for participants and relevant medical details like duration of treatment, glycaemic control, complications were recorded.

Results: A total of 145 diabetic individuals participated in this study. Out of these, 17.3% of individuals with T2DM screened positive for ED on EAT-26 scale and had a significant positive correlation in <20 groups and a significant negative correlation in >30 groups.

Conclusion: Our study reveals that eating disorders are not very common in our clinical population of T2DM, the prevalence rates of eating disorders are lower in patients with T2DM than those reported from developed western countries.

Type 1 diabetes mellitus (T1DM), associated with autoimmune destruction of pancreatic β cells, is observed in children and adolescents.

Objective: We investigated the potential association of the apolipoprotein M (APOM) polymorphisms rs707921, rs805264, rs805296, rs805297, and rs9404941 in childhood-onset T1DM (n = 144) and compared them to those in healthy (mostly Euro-Brazilian) children (n = 168).

Methods: This project was approved by the Ethics Committee of the Federal University of Parana (CAAE 24676613.6.0000.0102). Genotyping was performed using PCR-restriction fragment length polymorphisms (rs805296 and rs9404941) and TaqMan probes (rs707921, rs805264, and rs805297).

Results: All polymorphisms were in Hardy-Weinberg equilibrium. In the codominant model, no significant differences (P > 0.05) were observed in genotype and allele frequencies between healthy controls and children with T1DM. The minor allele frequencies (95% CI) for healthy subjects were rs707921 (A, 10.7%; 7-14%), rs805264 (A, 6.5%; 4-9%), rs805296 (C, 3.6%; 2-6%), rs805297 (A, 22.6%; 22-31%), and rs9404941 (C, 2.7%; 1-4%). The frequencies of the rs805297 A allele and rs805296 C allele were similar to those of other Caucasian populations; both the rs707921 and rs805264 A alleles were similar to American and Latin American populations, whereas that of the rs9404941 C allele was lower than that observed in the Caucasian and Asian populations.

Conclusions: Haplotype analysis suggests that rs805297-C, rs9404941-T, rs805296-T, rs805264-G, and rs707921-C conferred risk (OR: 4.25; 95% CI: 1.81-10.1) to childhood-onset T1DM in the Euro-Brazilian population.