(+)-Cholesten-3-one induces differentiation of neural stem cells into dopaminergic neurons through BMP signaling

Cotransplantation of NSCs and ethyl stearate promotes synaptic plasticity in PD rats by Drd1/ERK/AP-1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine views kidney shortage as a significant contributor to the aetiology of Parkinson's disease (PD), a neurodegenerative condition that is closely linked to aging. In clinical, patients with Parkinson's disease are often treated with Testudinis Carapax et Plastrum (Plastrum Testudinis, PT), a traditional Chinese medication that tonifies the kidney. Previous research has demonstrated that ethyl stearate (PubChem CID: 8122), an active component of Plastrum Testudinis Extracted with ethyl acetate (PTE), may encourage neural stem cells (NSCs) development into dopaminergic (DAergic) neurons. However, the effectiveness and mechanism of cotransplantation of ethyl stearate and NSCs in treating PD model rats still require further investigation.

AIM OF THE STUDY

PD is a neurodegenerative condition marked by the loss and degradation of dopaminergic neurons in the substantia nigra of the midbrain. Synaptic damage is also a critical pathology in PD. Because of their self-renewal, minimal immunogenicity, and capacity to differentiate into dopaminergic (DAergic) neurons, NSCs are a prospective treatment option for Parkinson's disease cell transplantation therapy. However, encouraging transplanted NSCs to differentiate into dopaminergic neurons and enhancing synaptic plasticity in vivo remains a significant challenge in improving the efficacy of NSCs transplantation for PD. This investigation seeks to examine the efficacy of cotransplantation of NSCs and ethyl stearate in PD model rats and its mechanism related to synaptic plasticity.

MATERIALS AND METHODS

On 6-hydroxydopamine-induced PD model rats, we performed NSCs transplantation therapy and cotransplantation therapy involving ethyl stearate and NSCs. Rotating behavior induced by apomorphine (APO) and pole climbing tests were used to evaluate behavioral changes. Using a variety of methods, including Western blotting (WB), immunofluorescence analysis, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction (qRT-PCR), we examined the function and potential molecular mechanisms of ethyl stearate in combined NSCs transplantation therapy.

RESULTS

In the rat PD model, cotransplantation of ethyl stearate with NSCs dramatically reduced motor dysfunction, restored TH protein levels, and boosted dopamine levels in the striatum, according to our findings. Furthermore, the expression levels of SYN1 and PSD95, markers of synaptic plasticity, and BDNF, closely related to synaptic plasticity, were significantly increased. Cotransplantation with ethyl stearate and NSCs also increased the expression levels of Dopamine Receptor D1 (Drd1), an important receptor in the dopamine neural circuit, accompanied by an increase in MMP9 levels, ERK1/2 phosphorylation levels, and c-fos protein levels.

CONCLUSIONS

According to the results of our investigation, cotransplantation of ethyl stearate and NSCs significantly improves the condition of PD model rats. We found that cotransplantation of ethyl stearate and NSCs may promote the expression of MMP9 by regulating the Drd1-ERK-AP-1 pathway, thus improving synaptic plasticity after NSCs transplantation. These findings provide new experimental support for the treatment of PD with the kidney tonifying Chinese medicine Plastrum Testudinis and suggest a potential therapeutic strategy for PD based on cotransplantation therapy.

Research progress of neural stem cells as a source of dopaminergic neurons for cell therapy in Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease, the most characteristic pathological feature is the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compactus (SNpc) of the mesencephalon, along with reduced dopamine content in the striatum. Researchers have been searching for drugs and therapies to treat PD in decades. However, no approach could stop the progression of the disease, and even some of them caused adverse clinical side effects. PD has a well-defined lesion. Therefore, it is considered to be one of the most curable central nervous system diseases by cell replacement treatment. Fetal ventral mesencephalic tissue transplantation has been used to treat patients with PD and obtained positive treatment results. However, ethical issues, such as limited donor tissue, and side effects including graft-induced dyskinesias, limit its clinical applications. Neural stem cell (NSC) transplantation is a viable therapy choice because it possesses multipotency, self-renewal ability, and differentiation into DA neurons, which may substitute for lost DA neurons and slow down the neurodegenerative process in PD. Studies that investigated the delivery of NSCs by using animal models of PD revealed survival, migration, and even amelioration of behavioral deficits. Here, the research progress of NSCs or NSC-derived DA neurons in treating PD was reviewed, and the practicability of present manufacturing processes for clinical testing was considered. This review is expected to offer ideas for practical strategies to solve the present technical and biological problems related to the clinical application of NSCs in PD.

The potential of plant extracts in cell therapy

Cell therapy is the frontier technology of biotechnology innovation and the most promising method for the treatment of refractory diseases such as tumours. However, cell therapy has disadvantages, such as toxicity and poor therapeutic effects. Plant extracts are natural, widely available, and contain active small molecule ingredients that are widely used in the treatment of various diseases. By studying the effect of plant extracts on cell therapy, active plant extracts that have positive significance in cell therapy can be discovered, and certain contributions to solving the current problems of attenuation and adjuvant therapy in cell therapy can be made. Therefore, this article reviews the currently reported effects of plant extracts in stem cell therapy and immune cell therapy, especially the effects of plant extracts on the proliferation and differentiation of mesenchymal stem cells and nerve stem cells and the potential role of plant extracts in chimeric antigen receptor T-cell immunotherapy (CAR-T) and T-cell receptor modified T-cell immunotherapy (TCR-T), in the hope of encouraging further research and clinical application of plant extracts in cell therapy.

The Effect of Traditional Chinese Medicine on Neural Stem Cell Proliferation and Differentiation

Neural stem cells (NSCs) are special types of cells with the potential for self-renewal and multi-directional differentiation. NSCs are regulated by multiple pathways and pathway related transcription factors during the process of proliferation and differentiation. Numerous studies have shown that the compound medicinal preparations, single herbs, and herb extracts in traditional Chinese medicine (TCM) have specific roles in regulating the proliferation and differentiation of NSCs. In this study, we investigate the markers of NSCs in various stages of differentiation, the related pathways regulating the proliferation and differentiation, and the corresponding transcription factors in the pathways. We also review the influence of TCM on NSC proliferation and differentiation, to facilitate the development of TCM in neural regeneration and neurodegenerative diseases.

(+)-Cholesten-3-one induces osteogenic differentiation of bone marrow mesenchymal stem cells by activating vitamin D receptor

In our previous reports, it was revealed that steroids in traditional Chinese medicine (TCM) have the therapeutic potential to treat bone disease. In the present study, an in vitro model of a vitamin D receptor response element (VDRE) reporter gene assay in mesenchymal stem cells (MSCs) was used to identify steroids that enhanced osteogenic differentiation of MSCs. (+)-cholesten-3-one (CN), which possesses a ketone group that is modified in cholesterol and cholesterol myristate, effectively promoted the activity of the VDRE promoter. Phenotypic cellular analysis indicated that CN induced differentiation of MSCs into osteogenic cells and increased expression of specific osteogenesis markers, including alkaline phosphatase, collagen II and Runt-related transcription factor 2. Furthermore, CN significantly increased the expression of osteopontin, the target of the vitamin D receptor (VDR), which indicated that CN may activate vitamin D receptor signaling. Over-expression of VDR or knockdown studies with VDR-small interfering RNA revealed that the pro-differentiation effects induced by CN required VDR. Furthermore, the present study determined that the C-terminal region of the VDR is responsible for the action of CN. Taken together, the present findings demonstrated that CN induced osteogenic differentiation of MSCs by activating VDR. The present study explored the regulation of stem cells by using a series of similar steroids and provided evidence to support a potential strategy for the screening of novel drugs to treat bone disease in the future.

Insights from Ayurveda for translational stem cell research

Ayurveda, the traditional Indian system of medicine has given great emphasis to the promotion of health. Ayurveda therapies are based on restoration of body balance and nourishment of dhatus or tissues. Rasayana concept of Ayurveda explains tissue regeneration and cell renewal. The drugs and therapies explained as rasayana provide research opportunities for biology of regeneration. Specific rasayana stimulate and nourish respective dhatus. Interpretation of this description offers clues for specific differentiation of stem cells with appropriate extract. The preliminary experiments on Medhya drugs suggest neuronal stem cells differentiation. Authors highlight the potential of Ayurveda and its possible contributions in regenerative medicine. Authors propose a protocol based on integrative approach derived from Ayurveda concepts and current understanding of regenerative medicine. The advanced understanding about adult and embryonic stem cells along with concepts of regeneration in Ayurveda has immense potential in the development of regenerative medicine.

Small molecules greatly improve conversion of human-induced pluripotent stem cells to the neuronal lineage

Efficient in vitro differentiation into specific cell types is more important than ever after the breakthrough in nuclear reprogramming of somatic cells and its potential for disease modeling and drug screening. Key success factors for neuronal differentiation are the yield of desired neuronal marker expression, reproducibility, length, and cost. Three main neuronal differentiation approaches are stromal-induced neuronal differentiation, embryoid body (EB) differentiation, and direct neuronal differentiation. Here, we describe our neurodifferentiation protocol using small molecules that very efficiently promote neural induction in a 5-stage EB protocol from six induced pluripotent stem cells (iPSC) lines from patients with Parkinson's disease and controls. This protocol generates neural precursors using Dorsomorphin and SB431542 and further maturation into dopaminergic neurons by replacing sonic hedgehog with purmorphamine or smoothened agonist. The advantage of this approach is that all patient-specific iPSC lines tested in this study were successfully and consistently coaxed into the neural lineage.