Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages

Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 at similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker^® staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration.     

Kinetics and Molecular Docking Study of an Anti-diabetic Drug Glimepiride as Acetylcholinesterase Inhibitor: Implication for Alzheimer’s Disease-Diabetes Dual Therapy

Neurochemical Research - At the present time, treatment of two most common degenerative disorders of elderly population i.e., Type 2 Diabetes Mellitus (T2DM) and Alzheimer’s disease (AD) is a...     

Identification of putative antiviral bioactive compounds derived from family Asteraceae: An in silico approach

This computational study investigates 21 bioactive compounds from the Asteraceae family as potential inhibitors targeting the Spike protein (S protein) of SARS-CoV-2. Employing in silico methods and simulations, particularly CDOCKER and MM-GBSA, the study identifies two standout compounds, pterodontic acid and cichoric acid, demonstrating robust binding affinities (−46.1973 and −39.4265 kcal/mol) against the S protein. Comparative analysis with Favipiravir underscores their potential as promising inhibitors. Remarkably, these bioactives exhibit favorable ADMET properties, suggesting safety and efficacy. Molecular dynamics simulations validate their stability and interactions, signifying their potential as effective SARS-CoV-2 inhibitors.     

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE.     

Molecular interaction analysis of cigarette smoke carcinogens NNK and NNAL with enzymes involved in DNA repair pathways: An in silico approach

DNA damage occurs almost all the times in cells, but is repaired also continuously. Occurrence of all these mutations and their accumulation in one cell which finally becomes tumorigenic/carcinogenic appears possible if the DNA repair mechanism is hampered. We hypothesize that alterations in DNA repair pathways, either all or at least at one i.e. genetic, translational or posttranslational level, becomes quite imperative for the initiation and progression of Cancer. Therefore, we investigated the interaction capability of some carcinogens with the enzymes involved in the DNA repair mechanisms. Cigarette smoke''s derivatives like NNK and NNAL are well established carcinogens. Hence, we analyzed 72 enzymes involved in the DNA repair Mechanisms for their interactions with ligands (NNK and NNAL). The binding efficiencies with enzymes ranging from +36.96 to -7.47 Kcal/Mol. Crystal Structure of Human Carbonmonoxy-Haemoglobin at 1.25 Å Resolution, PDB ID-1IRD as a +Ve control, showed binding energy -6.31 to -6.68 Kcal/Mol. and Human heat shock factor-binding protein 1, PDB ID- 3CI9 as a -Ve control, showed - 3.91 to +2.09 Kcal/Mol. Binding was characterized for the enzymes sharing equivalent or better interaction as compared to +Ve control. Study indicated the loss of functions of these enzymes, which probably could be a reason for fettering of DNA repair pathways resulting in damage accumulation and finally cancer formation.     

Continuous degradation of maltose by enzyme entrapment technology using calcium alginate beads as a matrix

Maltase from Bacillus licheniformis KIBGE-IB4 was immobilized within calcium alginate beads using entrapment technique. Immobilized maltase showed maximum immobilization yield with 4% sodium alginate and 0.2 M calcium chloride within 90.0 min of curing time. Entrapment increases the enzyme–substrate reaction time and temperature from 5.0 to 10.0 min and 45 °C to 50 °C, respectively as compared to its free counterpart. However, pH optima remained same for maltose hydrolysis. Diffusional limitation of substrate (maltose) caused a declined in V_max of immobilized enzyme from 8411.0 to 4919.0 U ml^?1 min^?1 whereas, K_m apparently increased from 1.71 to 3.17 mM ml^?1. Immobilization also increased the stability of free maltase against a broad temperature range and enzyme retained 45% and 32% activity at 55 °C and 60 °C, respectively after 90.0 min. Immobilized enzyme also exhibited recycling efficiency more than six cycles and retained 17% of its initial activity even after 6th cycles. Immobilized enzyme showed relatively better storage stability at 4 °C and 30 °C after 60.0 days as compared to free enzyme.     

Mapping the Structural Topology of IRS Family Cascades Through Computational Biology

Structural topologies of proteins play significant roles in analyzing their biological functions. Converting the amino acid data in a protein sequence into structural information to outline the function of a protein is a major challenge in post-genome research which can add an extra room in understanding the protein sequence–structure–function relationships. In this study, we performed a comprehensive bioinformatics analysis of structural topology of the IRS family members such as IRS-1, IRS-2, IRS-3, IRS-4, IRS-5 and IRS-6. Based on this assessment, we found that IRS-2 encloses the highest number of α helices, β sheets and β turns in the secondary structure topology compared to IRS-1 and IRS-6. IRS family members are rich in serine or leucine residues. Among the IRS family members, the highest percentage of serine and leucine was observed in IRS-1 (15 %) and IRS-5 (10 %), respectively. Notably, the highest number of disulphide bonds was observed in IRS-1 (10) which is responsible for structural stability of the protein. Hydrogen bond pattern in α helices and β sheet was recorded in IRS-1, IRS-2 and IRS-6. By conservation analysis, the longest protein IRS-3 was found to be highly conserved among the IRS family members. The cluster of sequence logo present in the N terminus of these cascades was noted, and highly conserved residues in N-terminal region help in the formation of the two highly conserved domains such as PH domain and PTB domain. Results generated from this analysis will be more beneficial to researchers in understanding more about insulin signalling mechanism(s) as well as insulin resistance pathway. We discuss here that bioinformatics tools utilized in this study can play a vital role in addressing the complexity of structural topology to understand structure–function relationships in insulin signalling cascades.     

Conditioned medium enhances the fusion capability of rat bone marrow mesenchymal stem cells and cardiomyocytes

Mesenchymal stem cells (MSCs) show accelerated regeneration potential when these cells experience hypoxic stress. This “preconditioning” has shown promising results with respect to cardio-protection as it stimulates endogenous mechanisms resulting in multiple cellular responses. The current study was carried out to analyze the effect of hypoxia on the expression of certain growth factors in rat MSCs and cardiomyocytes (CMs). Both cell types were cultured and assessed separately for their responsiveness to hypoxia by an optimized dose of 2,4,-dinitrophenol (DNP). These cells were allowed to propagate under normal condition for either 2 or 24 h and then analyzed for the expression of growth factors by RT-PCR. Variable patterns of expression were observed which indicate that their expression depends on the time of re-oxygenation and extent of hypoxia. To see whether the growth factors released during hypoxia affect the fusion of MSCs with CMs, we performed co-culture studies in normal and conditioned medium. The conditioned medium is defined as the medium in which CMs were grown for re-oxygenation till the specified time period of either 2 or 24 h after hypoxia induction. The results showed that the fusion efficiency of cells was increased when the conditioned medium was used as compared to that in the normal medium. This may be due to the presence of certain growth factors released by the cells under hypoxic condition that promote cell survival and enhance their fusion or regenerating ability. This study would serve as another attempt in designing a therapeutic strategy in which conditioned MSCs can be used for ischemic diseases and provide more specific therapy for cardiac regeneration.