miR-221/222 Promote Endothelial Differentiation of Adipose-Derived Stem Cells by Regulation of PTEN/PI3K/AKT/mTOR Pathway

Therapeutic role of PTEN in tissue regeneration for management of neurological disorders: stem cell behaviors to an in-depth review

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) represents the initial tumor suppressor gene identified to possess phosphatase activity, governing various cellular processes including cell cycle regulation, migration, metabolic pathways, autophagy, oxidative stress response, and cellular senescence. Current evidence suggests that PTEN is critical for stem cell maintenance, self-renewal, migration, lineage commitment, and differentiation. Based on the latest available evidence, we provide a comprehensive overview of the mechanisms by which PTEN regulates activities of different stem cell populations and influences neurological disorders, encompassing autism, stroke, spinal cord injury, traumatic brain injury, Alzheimer's disease and Parkinson's disease. This review aims to elucidate the therapeutic impacts and mechanisms of PTEN in relation to neurogenesis or the stem cell niche across a range of neurological disorders, offering a foundation for innovative therapeutic approaches aimed at tissue repair and regeneration in neurological disorders. This review unravels novel therapeutic strategies for tissue restoration and regeneration in neurological disorders based on the regulatory mechanisms of PTEN on neurogenesis and the stem cell niche.

miR-221 and Parkinson's disease: A biomarker with therapeutic potential

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra, leading to various motor and non-motor symptoms. Several cellular and molecular mechanisms such as alpha-synuclein (α-syn) accumulation, mitochondrial dysfunction, oxidative stress and neuroinflammation are involved in the pathogenesis of this disease. MicroRNAs (miRNAs) play important roles in post-transcriptional gene regulation. They are typically about 21-25 nucleotides in length and are involved in the regulation of gene expression by binding to the messenger RNA (mRNA) molecules. miRNAs like miR-221 play important roles in various biological processes, including development, cell proliferation, differentiation and apoptosis. miR-221 promotes neuronal survival against oxidative stress and neurite outgrowth and neuronal differentiation. Additionally, the role of miR-221 in PD has been investigated in several studies. According to the results of these studies, (1) miR-221 protects PC12 cells against oxidative stress induced by 6-hydroxydopamine; (2) miR-221 prevents Bax/caspase-3 signalling activation by stopping Bim; (3) miR-221 has moderate predictive power for PD; (4) miR-221 directly targets PTEN, and PTEN over-expression eliminates the protective action of miR-221 on p-AKT expression in PC12 cells; and (5) miRNA-221 controls cell viability and apoptosis by manipulating the Akt signalling pathway in PD. This review study suggested that miR-221 has the potential to be used as a clinical biomarker for PD diagnosis and stage assignment.

Pathology, Progression, and Emerging Treatments of Peripheral Artery Disease-Related Limb Ischemia

PURPOSE

This narrative review summarizes recent research examining treatment targets for peripheral artery disease (PAD)-related limb ischemia.

METHODS

Targeted searches of the PubMed and clinical trial registry databases were performed to identify recent findings from animal models of limb ischemia and clinical studies examining PAD progression and treatment. Ongoing clinical trials testing new treatments for PAD were also reviewed. Relevant full-text articles were retrieved and critically reviewed. Where indicated, data were tabulated and summarized in the text.

FINDINGS

Most people with PAD need treatment to improve their walking and function and limit leg pain. Currently, the available treatments of cilostazol, exercise therapy, and revascularization have several deficiencies, including limited access, poor uptake, limited efficacy, and risk of complications. Severe PAD threatens limb viability and is treated by endovascular or open surgical revascularization but is not always successful in achieving limb salvage. Research is ongoing to develop and test new therapies, including new exercise programs, drugs, stem cell treatments and RNA therapeutics, so that new and adjunctive PAD treatments can be offered. Results from multiple clinical trials are expected within the next 5 years.

IMPLICATIONS

It is envisaged that a range of new therapies for PAD will be available in the future.