Adipose tissue-derived mesenchymal stem cells ameliorate cognitive impairment in Alzheimer's disease rat model: Emerging role of SIRT1

Synergistic effects of curcumin and stem cells on spinal cord injury: a comprehensive review

Spinal cord injury (SCI) is damage to the spinal cord that permanently or temporarily disrupts its function, causing considerable autonomic, sensory, and motor disorders, and involves between 10 and 83 cases per million yearly. Traumatic SCI happens following primary acute mechanical damage, leading to injury to the spinal cord tissue and worsening clinical outcomes. The present therapeutic strategies for this complex disease fundamentally rely on surgical approaches and conservative remedies. However, these modalities are not effective enough for neurological recovery. Therefore, it is necessary to discover more efficient methods to treat patients with SCI. Today, considerable attention has been drawn to bioactive compounds-based remedies and stem cell therapy for curing various ailments and disorders, such as neurological diseases. Some researchers have recommended that harnessing curcumin, a polyphenol obtained from turmeric, in combination with stem cells, like mesenchymal stem cells, neural stem cells, and ependymal stem cells, can remarkably improve neurological recovery-related parameters more effective than the treatment with these two methods separately in experimental models. Hereby, this literature review delves into the functionality of curcumin combined with stem cells in treating SCI with a focus on cellular and molecular mechanisms.

Neuro-Adipokine Crosstalk in Alzheimer's Disease

The connection between body weight alterations and Alzheimer's disease highlights the intricate relationship between the brain and adipose tissue in the context of neurological disorders. During midlife, weight gain increases the risk of cognitive decline and dementia, whereas in late life, weight gain becomes a protective factor. Despite their substantial impact on metabolism, the role of adipokines in the transition from healthy aging to neurological disorders remains largely unexplored. We aim to investigate how the adipose tissue milieu and the secreted adipokines are involved in the transition between biological and pathological aging, highlighting the bidirectional relationship between the brain and systemic metabolism. Understanding the function of these adipokines will allow us to identify biomarkers for early detection of Alzheimer's disease and uncover novel therapeutic options.

Silencing of forkhead box protein O-1 (FOXO-1) enhances insulin-producing cell generation from adipose mesenchymal stem cells for diabetes therapy

AIMS

Generation of mature β-cells from MSCs has been a challenge in the field of stem cell therapy of diabetes. Adipose tissue-derived mesenchymal stem cells (Ad-MSCs) have made their mark in regenerative medicine, and provide several advantages compared to other MSCs sources. Forkhead box protein O-1 (FOXO-1) is an important transcription factor for normal development of β-cells, yet its over expression in β-cells may cause glucose intolerance. In this study, we isolated, characterized Ad-MSCs from rat epididymal fat pads, differentiated these MSCs into insulin producing cells (IPCs) and studied the role of FOXO-1 in such differentiation.

MATERIALS AND METHODS

We examined the expression of FOXO-1 and its nuclear cytoplasmic localization in the generated IPCs. Afterwards we knocked down FOXO-1 using siRNA targeting FOXO-1 (siFOXO-1). The differentiated siFOXO-1 IPCs were compared to non-targeting siRNA (siNT) IPCs regarding expression of β-cell markers by qRT-PCR and western blotting, dithizone (DTZ) staining and glucose stimulated insulin secretion (GSIS).

KEY FINDINGS

Isolated Ad-MSCs exhibited all characteristics of MSCs and can generate IPCs. FOXO-1 was initially elevated during differentiation followed by a decline towards end of differentiation. FOXO-1 was dephosphorylated and localized to the nucleus upon differentiation into IPCs. Knock down of FOXO-1 improved the expression of β-cell markers in final differentiated IPCs, improved DTZ uptake and showed increased insulin secretion upon challenging with increased glucose concentration.

SIGNIFICANCE

These results portray FOXO-1 as a hindering factor of generation of IPCs whose down-regulation can generate more mature IPCs for MSCs therapy of diabetes mellitus.

"Evaluation of neprilysin activity in Adipose-Derived stem cells from Alzheimer's disease patients"

INTRODUCTION

The antibody drugs targeting β-amyloid in Alzheimer's disease pose risks of inflammation and vascular damage. It is known that neprilysin, an endogenous enzyme responsible for β-amyloid degradation, is reduced in areas with β-amyloid deposition. Supplementation of neprilysin could potentially contribute to Alzheimer's disease treatment. When considering the use of adipose tissue-derived stem cells (ADSCs) for Alzheimer's disease therapy, it is crucial to ensure that Alzheimer's disease patient-derived ADSCs maintain neprilysin activity. If so, the use of autologous ADSCs may lead to a treatment with minimal risks of rejection or infection. Therefore, we investigated the neprilysin activity in Alzheimer's disease patient-derived adipose tissue-derived stem cells to assess their potential in Alzheimer's disease treatment.

METHODS

Five Alzheimer's disease patients (MSC1-5) and two Chronic Obstructive Pulmonary Disease (COPD) patients (MSC6-7) were enrolled. ADSCs were cultured for 6 days with varying seeding densities. On the 3rd day, the medium was replaced, and on the 6th day, ADSCs were harvested. Cells were stained for PE-Cy7 Mouse IgG1 κ Isotype control and PE-Cy Mouse Anti-Human CD10, and CD10 expression was assessed by flow cytometry. Ethical approval and informed consent were obtained.

RESULTS

Neprilysin activity, crucial for β-amyloid degradation, was assessed in ADSCs. Positivity rates for CD10 expression in ADSCs from Alzheimer's patients were consistently high: 99.6%, 99.5%, 99.9%, 99.3%, 99.8%, and 100.0%. Control ADSCs from COPD patients (MSC6-7) exhibited comparable positivity rates. Flow cytometry plots for all seven cases are presented in Figures 1-7.

DISCUSSION

This study confirms the presence and maintenance of neprilysin activity in ADSCs from Alzheimer's disease patients. The high positivity rates for CD10 expression in these cells suggest that neprilysin, a key enzyme in β-amyloid degradation, remains active. The implications are significant, as ADSCs offer immune-compatible and low infection risk advantages. The study underscores the potential of autologous ADSCs as a therapeutic approach in Alzheimer's disease. Their ability to naturally harbor neprilysin activity, coupled with their safety profile, makes them a promising candidate for further exploration. While acknowledging the need for larger, more diverse cohorts and long-term studies, these findings contribute to the growing body of evidence supporting the development of stem cell-based interventions in Alzheimer's disease treatment.

Melanin: a unifying theory of disease as exemplified by Parkinson's, Alzheimer's, and Lewy body dementia

Melanin, a ubiquitous dark pigment, plays important roles in the immune system, including scavenging reactive oxygen species formed in response to ultraviolet radiation absorption, absorbing metals, thermal regulation, drug uptake, innate immune system functions, redox, and energy transduction. Many tissue types, including brain, heart, arteries, ovaries, and others, contain melanin. Almost all cells contain precursors to melanin. A growing number of diseases in which there is a loss of melanin and/or neuromelanin are increasingly thought to have infectious etiologies, for example, Alzheimer's disease (AD), Parkinson's disease (PD), Lewy Body Dementia (LBD), and vitiligo. AD, PD, LBD, and vitiligo have been linked with herpesvirus, which enters melanosomes and causes apoptosis, and with gut dysbiosis and inflammation. Herpesvirus is also linked with gut dysbiosis and inflammation. We theorize that under normal healthy states, melanin retains some of the energy it absorbs from electromagnetic radiation, which is then used to fuel cells, and energy from ATP is used to compliment that energy supply. We further theorize that loss of melanin reduces the energy supply of cells, which in the case of AD, PD, and LBD results in an inability to sustain immune system defenses and remove the plaques associated with the disease, which appear to be part of the immune system's attempt to eradicate the pathogens seen in these neurodegenerative diseases. In addition, in an attempt to explain why removing these plaques does not result in improvements in cognition and mood and why cognitions and moods in these individuals have ebbs and flows, we postulate that it is not the plaques that cause the cognitive symptoms but, rather, inflammation in the brain resulting from the immune system's response to pathogens. Our theory that energy retained in melanin fuels cells in an inverse relationship with ATP is supported by studies showing alterations in ATP production in relationship to melanin levels in melanomas, vitiligo, and healthy cells. Therefore, alteration of melanin levels may be at the core of many diseases. We propose regulating melanin levels may offer new avenues for treatment development.