Adipose Tissue-Derived Mesenchymal Stem Cells Alter Metabolites of Brain Cholesterol Homeostasis in An Alzheimer's Model.

OBJECTIVE: Disruption of cholesterol homeostasis in Alzheimer's disease (AD) plays a crucial role in disease pathogenesis, making it a potential therapeutic target. Mesenchymal stem cells (MSCs) show promise in treating cognitive impairment and provide a novel therapeutic approach. This study aims to investigate the effects of MSCs on specific metabolites associated with brain cholesterol homeostasis in an AD rat model. MATERIALS AND METHODS: In this experimental study, animals were divided into three groups: control, AD, and AD+MSCs. AD was induced using amyloid beta (Aß) and confirmed through the Morris water maze (MWM) behavioural test and Congo red staining. MSCs were extracted, characterised via flow cytometry, subjected to osteoblast and adipose differentiation, and injected intraventricularly. The cholesterol metabolite levels were measured using gas chromatography-mass spectrometry (GC)-MS and compared among the groups. RESULTS: Treatment with MSCs significantly improved memory function in the AD+MSCs group compared to the AD group and the number of beta-amyloid plaques decreased according to histological assessment. Disturbances in the brain cholesterol metabolites that included desmosterol, 7-dehydrocholesterol, 24S-hydroxycholesterol, 27-hydroxycholesterol and cholesterol were observed in the AD group compared to the control group. Treatment with MSCs resulted in significant alterations in the levels of these metabolites. CONCLUSION: The findings indicate that MSC therapy has the potential to improve AD by modulating brain cholesterol homeostasis and promoting the differentiation of stem cells into nerve cells. The results emphasize the importance of investigating the role of cholesterol metabolites in the context of MSC therapy to gain deeper insights into underlying mechanisms of the therapeutic efficacy of MSCs in AD.

The Effect of Platelet-Rich Plasma on the Osteoblastic Differentiation of Human Adipose Tissue-Derived Mesenchymal Stromal Cells.

BACKGROUND: Mesenchymal stem cells (MSCs) are cell populations that have the potential to proliferate and differentiate. The process of stem cell differentiation from pluripotent cells to bone cells requires general changes in their pattern of gene expression, the most well-known of which are changes in miRNA-dependent settings. Platelet-enriched plasma (PRP) releases growth factors that are mitogenic to mesenchymal cells and can accelerate the process of osteogenic differentiation. The aim of this study was to investigate the effect of PRP on the expression changes of Let-7a, mir-27a, mir-31, mir-30c, mir-21, and mir-106a during osteogenic differentiation. METHODS: MSCs were isolated from adipose tissue after abdominoplasty and evaluated by flow cytometry. The ef-fect of PRP (10%) on the process of osteogenic differentiation was determined by measuring the expression of Let-7a, mir-27a, mir-31, mir-30c, mir-21, and mir-106a using the real-time polymerase chain reaction (PCR) technique. RESULTS: The increase in Let-7a expression was significant on the 14th day compared to the 3rd day. mir-27a expression rose significantly on the 3rd day. The expression of mir-30 exhibited a significant increase on the 14th day. mir-21 expression was significantly enhanced on the 3rd day and was downregulated on the 14th day. mir-106a expression showed a significant decreasing tendency between days 3 and 14 in a time-dependent pattern. CONCLUSIONS: These findings indicate that PRP probably accelerates the process of differentiation into bone. PRP, as a biological catalyst, showed a clear and distinct impact on the miRNAs regulating bone differentiation of human mesenchymal cells.

Mesenchymal Stem Cells Therapy Led to the Improvement of Spatial Memory in Rats with Alzheimer's disease Through Changing the Expression of LncRNA TUSC7/ miR-449a/ PPARγ and CD36 Genes in the Brain Tissue.

Mesenchymal stem cells (MSCs) have the ability to phagocytize amyloid beta (Aß) plaques and lower inflammation through the activity of microglia. Peroxisome proliferator-activated receptor gamma (PPARγ) is a protein involved in reducing inflammation through the activity of microglia and the phagocytosis of Aß plaques by scavenger receptor CD36, in this study, the effect of MSCs therapy on memory function and plaques was investigated. A total of 24 adult male Wistar rats were randomly divided into three groups:1) the control group, 2) the Aß-treated group (Alzheimer's disease (AD)), and 3) the MSC-treated group (AD + MSC). After the treatment with Aß and MSCs, western blotting and real-time polymerase chain reaction (PCR) techniques were used to assess protein and gene expression levels, respectively. MSCs improved spatial learning and memory in the AD group (p ≤0.05). The expression levels of PPARγ, lncRNA TUSC7, and CD36 genes were significantly elevated in the group receiving MSCs compared to the AD group (p≤0.0001). Also, the expression level of miR-449a significantly decreased in the AD + MSC group (p≤0.0001). Moreover, western blot analysis revealed that PPARγ and CD36 protein levels were enhanced in the AD + MSC group compared to the AD group (p≤0.0001). MSC treatment led to the positive regulation of the PPARγ gene and its protein expression by ncRNAs, which could have a beneficial impact on CD36 protein levels, and subsequently, reduce the number of plaques in the cell recipient.

Diabetes mellitus and COVID-19: review of a lethal interaction from the cellular and molecular level to the bedside.

INTRODUCTION: While the main mode of transmission of coronavirus disease 2019 (COVID-19) is close contact with other individuals, the presence of chronic underlying diseases such as Diabetes Mellitus (DM) increases the chance of hospitalization and mortality rate due to infection. AREAS COVERED: To investigate the effects of COVID-19 infection in DM patients, we reviewed literature from Google Scholar search engine and PubMed database from '2013 to 2020' using the terms "COVID-19; SARS-CoV-2; Diabetes mellitus; obesity; Angiotensin-converting enzyme 2; ACE2; Insulin and Metformin. Evidence suggests that COVID-19 exacerbates the course of diabetes. Presence of pro-inflammatory conditions, increased expression of receptors, and more difficult control of glucose levels in diabetics COVID-19 patients are some of the problems that diabetic patients may face. Also, psychological problems caused by the COVID-19 epidemic in diabetic patients is one of the most important problems in these patients, which is less covered. EXPERT OPINION: DM is a strong and independent risk factor with a poor prognosis, which increases the risk of COVID-19 infection, the need for emergency services, the rate of hospitalization in the intensive care unit and also increases the mortality rate of COVID-19 patients.