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As current treatments for Alzheimer's disease (AD) lack disease‐modifying interventions, novel therapies capable of restraining AD progression and maintaining better brain function have great significance. Anti‐inflammatory extracellular vesicles (EVs) derived from human induced pluripotent stem cell (hiPSC)‐derived neural stem cells (NSCs) hold promise as a disease‐modifying biologic for AD. This study directly addressed this issue by examining the effects of intranasal (IN) administrations of hiPSC‐NSC‐EVs in 3‐month‐old 5xFAD mice. IN administered hiPSC‐NSC‐EVs incorporated into microglia, including plaque‐associated microglia, and encountered astrocyte soma and processes in the brain. Single‐cell RNA sequencing revealed transcriptomic changes indicative of diminished activation of microglia and astrocytes. Multiple genes linked to disease‐associated microglia, NOD‐, LRR‐, and pyrin domain‐containing protein 3 (NLRP3)‐inflammasome and interferon‐1 (IFN‐1) signalling displayed reduced expression in microglia. Adding hiPSC‐NSC‐EVs to cultured human microglia challenged with amyloid‐beta oligomers resulted in similar effects. Astrocytes also displayed reduced expression of genes linked to IFN‐1 and interleukin‐6 signalling. Furthermore, the modulatory effects of hiPSC‐NSC‐EVs on microglia in the hippocampus persisted 2 months post‐EV treatment without impacting their phagocytosis function. Such effects were evidenced by reductions in microglial clusters and inflammasome complexes, concentrations of mediators, and end products of NLRP3 inflammasome activation, the expression of genes and/or proteins involved in the activation of p38/mitogen‐activated protein kinase and IFN‐1 signalling, and unaltered phagocytosis function. The extent of astrocyte hypertrophy, amyloid‐beta plaques, and p‐tau were also reduced in the hippocampus. Such modulatory effects of hiPSC‐NSC‐EVs also led to better cognitive and mood function. Thus, early hiPSC‐NSC‐EV intervention in AD can maintain better brain function by reducing adverse neuroinflammatory signalling cascades, amyloid‐beta plaque load, and p‐tau. These results reflect the first demonstration of the efficacy of hiPSC‐NSC‐EVs to restrain neuroinflammatory signalling cascades in an AD model by inducing transcriptomic changes in activated microglia and reactive astrocytes. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is characterized by the accumulation of amyloid‐beta (Aβ) in the extracellular space, which leads to various adverse effects such as oxidative stress, neuroinflammation, mitochondrial dysfunction, tau phosphorylation, synapse loss, and neurodegeneration. Therefore, therapeutic interventions that can reduce Aβ‐toxicity and slow down the progression of cognitive dysfunction in AD have significance. One promising approach is to use extracellular vesicles (EVs) that are released by neural stem cells (NSCs) derived from human induced pluripotent stem cells (hiPSCs). These EVs contain therapeutic proteins and miRNAs that can help protect against Aβ‐induced pathological changes in the brain, providing a potential avenue for neuroprotection. Method: This study first isolated and characterized EVs secreted from hiPSC‐NSCs by chromatographic methods. Next, mature human neurons generated from 2 different hiPSC lines were exposed to 1‐µM Aβ42 oligomers with different concentrations of hNSC‐EVs. The protective effects of EVs on neurons exposed to Aβ were quantified using MTT and live/dead cell assays and counting of surviving MAP‐2+ neurons. The extent of oxidative stress was investigated via measurements of malondialdehyde (MDA) and protein carbonyls (PCs) and the expression of genes encoding iNos and Cox2. Furthermore, the expression of genes and/or proteins linked to pro‐apoptotic (Bad, Bax) and antiapoptotic (Bcl2) effects, mitochondrial respiratory chain (Nudfs6, Nudfs7, Sdha, Sdhb, Cyc1, Bcs11, Cox6a1, Atp6ap1), autophagy (Beclin 1 and MAPILC3B) were quantified. Total tau and p‐tau were also measured. Result: The addition of hiPSC‐NSC‐EVs to mature human neuronal cultures exposed to Aβ reduced the extent of Aβ‐induced neurodegeneration. When human neurons were exposed to Aβ‐42 alone, it increased pro‐apoptotic genes (Bad, Bax) and reduced the expression of an antiapoptotic gene (BCL‐2). However, adding hNSC‐EVs to Aβ‐42 exposed neurons normalized the expression of pro‐ and antiapoptotic genes to control levels, reduced oxidative stress markers, prevented Aβ‐42‐induced hyperactivation of mitochondria and decreased autophagy, reduced the phosphorylation of tau. Conclusion: Treating human neurons with hiPSC‐NSC‐EVs can significantly decrease the various pathological changes caused by Aβ exposure. Supported by a grant from the National Institute for Aging (1RF1AG074256‐01A1 to A.K.S.) [ABSTRACT FROM AUTHOR]

Background: Current treatments for Alzheimer's disease (AD) lack disease‐modifying interventions. Hence, novel therapies capable of restraining AD progression and maintaining better brain function for extended periods after the initial diagnosis have great significance. Extracellular vesicles (EVs) from human induced pluripotent stem cell (hiPSC)‐derived neural stem cells (NSCs) are attractive in this context due to their robust antiinflammatory properties. Method: Three‐month‐old 5x familial AD (5xFAD) mice received IN administration of hiPSC‐NSC‐EVs (∼30 billion EVs) or the vehicle (weekly for two weeks). Seventy‐two hours later, a cohort of mice was euthanized, fresh microglia were isolated from the brain, and the expression of genes linked to DAM and NLRP3‐inflammasome signaling was examined via scRNA‐sequencing. Another cohort of 5xFAD mice was investigated for cognitive and mood function commencing one‐month post‐EV/Veh administration and euthanized two months post‐EV/Veh administration to assess the effects on long‐term progressive increases in neuroinflammation, amyloid‐beta plaques, and phosphorylated tau (p‐tau). Result: Microglia in all brain regions, including plaque‐associated microglia, internalized hiPSC‐NSC‐EVs entering the brain. Single‐cell RNA sequencing at 72 hours post‐EV administration revealed microglia with transcriptomic changes indicative of diminished activation. Multiple genes linked to disease‐associated microglia, NOD‐, LRR‐ and pyrin domain‐containing protein 3 (NLRP3)‐inflammasome and interferon‐1 signaling displayed reduced expression. Adding hiPSC‐NSC‐EVs to cultured human microglia challenged with amyloid‐beta oligomers also resulted in similar effects. Furthermore, the modulatory effects of hiPSC‐NSC‐EVs on microglia in the hippocampus persisted even two months post‐EV treatment, evidenced by reductions in microglial clusters and inflammasome complexes, concentrations of mediators, and end products of NLRP3 inflammasome activation, the expression of genes and proteins involved in p38/mitogen‐activated protein kinase hyperactivation, and proteins linked to activation of interferon‐1 signaling. The hippocampus also exhibited reduced amyloid‐beta plaques and p‐tau. Such modulatory effects of hiPSC‐NSC‐EVs also led to better cognitive and mood function. Conclusion: Early hiPSC‐NSC‐EV intervention in AD can maintain better brain function by reducing adverse neuroinflammatory signaling cascades, amyloid‐beta plaque load, and p‐tau. Supported by a grant from the National Institute for Aging (1RF1AG074256‐01A1 to A.K.S.) [ABSTRACT FROM AUTHOR]

Context: The proliferation and differentiation of human periodontal ligament stem cells (hPDLSC) into other cell types are also mediated by mechanical stresses; they might offer therapeutic benefits in tissue regeneration and angiogenesis. Objectives: The study was planned to assess the proliferation, clonogenic potential, and osteogenic differentiation of human periodontal ligament stem cells (PDLSC) following the application of light and heavy orthodontic forces. Materials and Methods: A couple forces of 50 gm (light force) were applied on the 1st premolar on the one side and 250 gm (heavy force) on the contralateral side in the upper arch of patients requiring orthodontic treatment with extraction of all 1st premolars. After 30 days, periodontal tissues were scrapped from extracted teeth for the establishment of PDLSC in vitro. PDLC from the lower premolar teeth where no orthodontic force was applied acted as the control group. Morphology, viability, proliferating rate and population doubling time, clonogenicity, and alkaline phosphatase activity were analysed. Result: The osteogenic potential was confirmed by Alizarin red staining and the expression of the osteogenic markers by qRT-PCR. The morphology, growth kinetics, potency, and osteogenic lineage characteristics inferred the application of high force reduced the proliferative ability and osteogenesis of PDLSC, though the difference was not significant. Conclusion: The established PDLSCs demonstrated their MSC-like properties based on morphology, growth kinetics, colony forming ability, and AP activity. The culture-expanded PDLSCs showed their differentiation potential into osteocytes. The application of high force reduced the proliferative ability and osteogenesis of PDLSCs, variations were not significant. [ABSTRACT FROM AUTHOR]

Objectives: Dental tissues possess multipotent stem cells with varying biological properties. The present study was aimed to establish a primary culture of human gingiva-derived mesenchymal stem cells (GMSCs) and periodontal ligamentderived stem cells (PDLSCs) from periodontally healthy subjects and compare their biological characteristics. Materials and Methods: Gingival and periodontal ligament (PDL) tissues were collected from extracted premolar teeth of five healthy subjects and primary cultures were established. Basic biological characteristics, such as cell morphology, viability, proliferation capacity, and colony-forming units, and in vitro osteogenic and adipogenic differentiation potential were performed at passage 3 of GMSCs and PDLSCs. This was followed by immuno-phenotyping and flow cytometric analysis for identification of positive mesenchymal stem cell (MSC) markers, such as CD73, CD90, and CD105, and negative markers CD45 and CD34. Statistical Analysis Used: One-way analysis of variance (ANOVA). Results: Primary cultures of GMSCs and PDLSCs were successfully established. Cells exhibited a fibroblast-like morphology with a homogeneous population at passage 3. Cells derived from both tissues were highly viable (>95%), proliferative, and capable of forming colonies. Both cells did not exhibit any noticeable differences in cellular properties. Immunofluorescence and flow cytometric analyses showed positivity for MSC markers, CD73, CD90, and CD105, and negativity for CD34 and CD45. Furthermore, GMSCs and PDLSCs were capable of differentiating in vitro into osteocytes as evidenced by Alizarin red-S staining, and adipocytes as demonstrated by oil red O staining. Conclusions: The results of the present study indicate that both GMSCs and PDLSCs have similar cellular characteristics and mesenchymal differentiation potential. Therefore, they may serve as an equally potent source of stem cells for use in cell-based periodontal therapies. [ABSTRACT FROM AUTHOR]

Objective: Gingiva-derived mesenchymal stem cells (GMSCs) have been identified and characterized from healthy tissues. However, reports on the influence of chronic inflammation on their stemness characteristics are sparse. The present study evaluated the potency and differentiation ability of GMSCs from periodontally healthy GMSC (H-GMSC) and inflamed GMSC (I-GMSC) tissues. Materials and Methods: Established H-GMSCs and I-GMSCs were evaluated on their potency characteristics, such as morphology, viability, proliferation rate, population doubling time, colony-forming ability, expression of stemness markers, and mesenchymal differentiation potential. Results: H-GMSCs and I-GMSCs exhibited fibroblast-like morphology and showed >95% viability with high proliferation potential and shorter doubling time. H-GMSCs showed fewer and smaller colonies, whereas I-GMSCs exhibited multiple and larger colonies. The evaluation of stemness markers revealed that both H-GMSCs and I-GMSCs were weakly positive for stage-specific embryonic antigen-4, Stro1, and CD105 (Endoglin), strongly positive for CD73 and CD90, and negative for the hematopoietic cell markers, CD34 and CD45. H-GMSCs showed a slightly higher osteogenic potential when compared to I-GMSCs, while I-GMSCs had a higher adipogenic potential than H-GMSCs. Conclusion: The findings showed that the inflammatory environment might have a stimulatory effect on the growth kinetics and ability of colony formation in GMSCs. However, varied osteogenic and adipogenic differentiation was observed between H-GMSCs and I-GMSCs. [ABSTRACT FROM AUTHOR]

Background: Tumor cells that have the ability to express vascular endothelial growth factor (VEGF) are more competent to growth and metastasize by the adequate amount of blood and oxygen supply by the blood vessels to the growing mass of cells. Hypoxic tumors are known for its aggressiveness and resistance to the treatment. Targeting VEGF and hypoxia‑inducible factor‑1 alpha (HIF‑1α) is an attractive strategy to interrupt the multiple pathways crucial for tumor growth. In the present study, two thiazole acetamide derivative’s anticancer property, anti VEGF and HIF‑1α inhibitory property were investigated. Methodology: Two thiazole acetamide compounds were synthesized, TA1 and TA2 and its anticancer property was studied in Erlich’s ascites cancer cells. To evaluate the anticancer property the assays such as 3‑(4,5‑dimethylthiazol‑2‑yl)‑2,5‑diphenyltetrazolium bromide assay, DNA diffusion assay for apoptosis, and lactate dehydrogenase leakage assay were carried out. The cell culture media was used to assess the secreted VEGF level. Molecular docking studies were performed to analyze the binding efficiency of the study compounds to the kinase insert domain‑containing receptor (KDR) and fms‑like tyrosine kinase (FLT)‑binding domains of VEGF protein. HIF‑1α inhibitory study was performed by flow cytometry analysis using HUVEC cell line. Results: The study compounds inhibited HIF‑1α and VEGF secretion, these data shown positive prop up for the anticancer property of the derivatives. The docking studies showed moderate binding of study compounds to KDR and FLT‑binding domains of VEGF protein. Conclusion: These results conclude the anticancer and anti‑angiogenic property of the synthesized thiazole‑acetamide derivatives. [ABSTRACT FROM AUTHOR]

Context: Dental tissue remains are the toughest, and chemically, the most stable tissue in the body. Its high resilience in the events of fire and bacterial decomposition makes them vital for DNA analysis by PCR method.Aims: Determination of sex of children through molecular analysis of pulp tissue of exfoliated deciduous teeth stored in different media and analyzed after a different time period.Settings and Design: Sixty samples of deciduous teeth were divided into three groups. Group IA and Group IIA were stored in natural soil and wet clay for 1 month, respectively. Group IB and Group IIB were stored in natural soil and wet clay for 6 months, respectively. Group III was analyzed immediately after extraction.Methods and Material: Sex determination was carried out in five steps: Pulp tissue removal, DNA isolation, DNA quantification, PCR amplification, Sex determination. X and Y specific chromosomes from each sample were amplified and compared.Statistical Analysis Used: Kruskal-Wallis test, Dunn's test, and Wilcoxon signed rank test.Results: Group III revealed the highest amount of DNA quantified. Amount of DNA quantified after 6 months of storage in natural soil and wet clay decreased in both the groups with the samples stored in wet clay showing a maximum decrease. Results of the PCR analysis also showed 100% accuracy rate in the samples of Group III.Conclusions: Sex determination from pulp tissue depends a lot on the quality and quantity of DNA extracted. Sex could be effectively determined among the samples evaluated immediately after extraction. This ability decreases as the storage condition changes and the time period increases. Samples stored in wet clay were found to show the least sex identification ability than dry soil. [ABSTRACT FROM AUTHOR]

Background: Accurate determination of gender from the skeletal remains has a significant role in the identification process. In conditions of extreme fragmentation, information from DNA plays a vital role in establishing the gender of the person and further contributes to personal identification. Method: Sixty sound and non-carious extracted deciduous teeth were grouped into three of 20 each. Group 1 was analyzed immediately after extraction. Group 2 and Group 3 were stored at room temperature for three months and Fifteen months respectively before subjecting them to PCR analysis. The X and Y chromosomes from each sample were amplified and compared with the actual gender of the person. Shapiro-Wilk test the independent sample t-test, paired t-test and the chi-square test were used to analyze the data obtained. Result: The mean DNA volume (mg/ml) obtained immediately after extraction was significantly more than that from the teeth stored at room temperature for 15 months. The PCR analysis did not show any significant difference between group 1 and group 3 (p=0.072). Statistically significant difference was observed, when the results of group 1 were compared with that of group 3. Conclusion: Gender could be conclusively determined from the samples analyzed immediately after extraction. The accuracy of gender determination decreased as the period of storage increased. [ABSTRACT FROM AUTHOR]

Introduction: Diallyl disulphide is an organo-sulphur compound which is present in garlic and responsible for the characteristic odor of garlic. It is known for its anticancer and invitro membrane stabilizing properties. Aim: The main aim was to evaluate the haematopoietic, antioxidant and membrane stabilizing property of diallyl disulfide in irradiated mice. Materials and Methods: Mice were grouped into 6 groups as control, drug control, radiation control and drug pre-treatment groups (i.e. drug administration + radiation group) The mice were fed orally for 15 consecutive days and on the 15th day, one hour after drug administration, the mice were irradiated with 6Gy electron beam radiation. The changes in blood cell count, total antioxidant levels, malondialdehyde and reduced glutathione levels were determined. The immunomodulatory response of DADS to the radiological effects was determined by the estimation of IL-6 levels. Results: A significant improvement in pre-drug treatment group when compared to control groups in the haemoglobin, red blood cell count, white blood cell count, haematocrit and platelet counts was observed. There is an increased level of interleukin-6 in the drug treated groups compared to the radiation control. An increase in the malondialdehyde levels and decrease in the glutathione levels in the irradiated group indicate increased lipid peroxidation and oxidative stress, whereas, there is a significant reduction in the malondialdehyde levels and increased glutathione levels in the drug pre-treatment groups showing membrane stabilization. Conclusion: Thus DADS proves to be an effective haematopoietic and antioxidative agent to counter radiation induced haematopoietic suppression and oxidative stress. [ABSTRACT FROM AUTHOR]

While moderately activated microglia in Alzheimer's disease (AD) are pivotal in clearing amyloid beta (Aβ), hyperactivated microglia perpetuate neuroinflammation. Prior investigations reported that the elimination of ~80% of microglia through inhibition of the colony‐stimulating factor 1 receptor (CSF1R) during the advanced stage of neuroinflammation in 5xFamilial AD (5xFAD) mice mitigates synapse loss and neurodegeneration. Furthermore, prolonged CSF1R inhibition diminished the development of parenchymal plaques. Nonetheless, the effects of short‐term CSF1R inhibition during the early stages of neuroinflammation on residual microglia are unknown. Therefore, we investigated the effects of 10‐day CSF1R inhibition using PLX5622 in three‐month‐old female 5xFAD mice, a stage characterized by the onset of neuroinflammation and minimal Aβ plaques. We observed ~65% microglia depletion in the hippocampus and cerebral cortex. The leftover microglia displayed a noninflammatory phenotype with reduced NOD‐, LRR‐, and pyrin domain‐containing protein 3 (NLRP3) inflammasome complexes. Moreover, plaque‐associated microglia were reduced with diminished Clec7a expression. Additionally, phosphorylated S6 ribosomal protein and the protein sequestosome 1 analysis suggested reduced mechanistic targets of rapamycin (mTOR) signaling and autophagy in microglia and neurons within the hippocampus and cerebral cortex. Biochemical assays validated the inhibition of NLRP3 inflammasome activation, decreased mTOR signaling in the hippocampus and cerebral cortex, and enhanced autophagy in the hippocampus. However, short‐term CSF1R inhibition did not influence Aβ plaques, soluble Aβ‐42 levels, astrocyte hypertrophy, or hippocampal neurogenesis. Thus, short‐term CSF1R inhibition during the early stages of neuroinflammation in 5xFAD mice promotes the retention of homeostatic microglia with diminished inflammasome activation and mTOR signaling, alongside increased autophagy. [ABSTRACT FROM AUTHOR]