Taxifolin Protects Dental Pulp Stem Cells under Hypoxia and Inflammation Conditions

Traditional herbal medicine: Therapeutic potential in acute gouty arthritis

ETHNOPHARMACOLOGICAL RELEVANCE

Acute gouty arthritis (AGA) is characterized by a rapid inflammatory reaction caused by the build-up of monosodium urate (MSU) crystals in the tissues surrounding the joints. This condition often associated with hyperuricemia (HUA), is distinguished by its symptoms of intense pain, active inflammation, and swelling of the joints. Traditional approaches in AGA management often fall short of desired outcomes in clinical settings. However, recent ethnopharmacological investigations have been focusing on the potential of Traditional Herbal Medicine (THM) in various forms, exploring their therapeutic impact and targets in AGA treatment.

AIM OF THE REVIEW

This review briefly summarizes the current potential pharmacological mechanisms of THMs - including active ingredients, extracts, and prescriptions -in the treatment of AGA, and discusses the relevant potential mechanisms and molecular targets in depth. The objective of this study is to offer extensive information and a reference point for the exploration of targeted AGA treatment using THMs.

MATERIALS AND METHODS

This review obtained scientific publications focused on in vitro and in vivo studies of anti-AGA THMs conducted between 2013 and 2023. The literature was collected from various journals and electronic databases, including PubMed, Elsevier, ScienceDirect, Web of Science, and Google Scholar. The retrieval and analysis of relevant articles were guided by keywords such as "acute gouty arthritis and Chinese herbal medicine," "acute gouty arthritis herbal prescription," "acute gouty arthritis and immune cells," "acute gouty arthritis and inflammation," "acute gouty arthritis and NOD-like receptor thermoprotein domain associated protein 3 (NLRP3)," "acute gouty arthritis and miRNA," and "acute gouty arthritis and oxidative stress."

RESULTS

We found that AGA has a large number of therapeutic targets, highlighting the effectiveness the potential of THMs in AGA treatment through in vitro and in vivo studies. THMs and their active ingredients can mitigate AGA symptoms through a variety of therapeutic targets, such as influencing macrophage polarization, neutrophils, T cells, natural killer (NK) cells, and addressing factors like inflammation, NLRP3 inflammasome, signaling pathways, oxidative stress, and miRNA multi-target interactions. The anti-AGA properties of THMs, including their active components and prescriptions, were systematically summarized and categorized based on their respective therapeutic targets.

CONCLUSION

phenolic, flavonoid, terpenoid and alkaloid compounds in THMs are considered the key ingredients to improve AGA. THMs and their active ingredients achieve enhanced efficacy through interactions with multiple targets, of which NLRP3 is a main therapeutic target. Nonetheless, given the intricate composition of traditional Chinese medicine (TCM), additional research is required to unravel the underlying mechanisms and molecular targets through which THMs alleviate AGA.

Role of Hypoxia in Mesenchymal Stem Cells from Dental Pulp: Influence, Mechanism and Application

Mesenchymal stem cells (MSCs) from dental pulp (DP-MSCs), which include dental pulp stem cells (DPSCs) isolated from permanent teeth and stem cells from human exfoliated deciduous teeth (SHED), have emerged as highly promising cell sources for tissue regeneration, due to their high proliferative rate, multi-lineage differentiation capability and non-invasive accessibility. DP-MSCs also exert extensive paracrine effects through the release of extracellular vesicles (EVs) and multiple trophic factors. To be noted, the microenvironment, commonly referred to as the stem cell niche, plays a crucial role in shaping the functionality and therapeutic effects of DP-MSCs, within which hypoxia has garnered considerable attention. Extensive research has demonstrated that hypoxic conditions profoundly impact DP-MSCs. Specifically, hypoxia promotes DP-MSC proliferation, survival, stemness, migration, and pro-angiogenic potential while modulating their multi-lineage differentiation capacity. Furthermore, hypoxia stimulates the paracrine activities of DP-MSCs, leading to an increased production of EVs and soluble factors. Considering these findings, hypoxia preconditioning has emerged as a promising approach to enhance the therapeutic potential of DP-MSCs. In this comprehensive review, we provide a systematic overview of the influence of hypoxia on DP-MSCs, shedding light on the underlying mechanisms involved. Moreover, we also discuss the potential applications of hypoxia-preconditioned DP-MSCs or their secretome in tissue regeneration. Additionally, we delve into the methodologies employed to simulate hypoxic environments. This review aims to promote a comprehensive and systematic understanding of the hypoxia-induced effects on DP-MSCs and facilitate the refinement of regenerative therapeutic strategies based on DP-MSCs.

Molecules Inducing Dental Stem Cells Differentiation and Bone Regeneration: State of the Art

Teeth include mesenchymal stem cells (MSCs), which are multipotent cells that promote tooth growth and repair. Dental tissues, specifically the dental pulp and the dental bud, constitute a relevant source of multipotent stem cells, known as dental-derived stem cells (d-DSCs): dental pulp stem cells (DPSCs) and dental bud stem cells (DBSCs). Cell treatment with bone-associated factors and stimulation with small molecule compounds are, among the available methods, the ones who show excellent advantages promoting stem cell differentiation and osteogenesis. Recently, attention has been paid to studies on natural and non-natural compounds. Many fruits, vegetables, and some drugs contain molecules that can enhance MSC osteogenic differentiation and therefore bone formation. The purpose of this review is to examine research work over the past 10 years that has investigated two different types of MSCs from dental tissues that are attractive targets for bone tissue engineering: DPSCs and DBSCs. The reconstruction of bone defects, in fact, is still a challenge and therefore more research is needed; the articles reviewed are meant to identify compounds useful to stimulate d-DSC proliferation and osteogenic differentiation. We only consider the results of the research which is encouraging, assuming that the mentioned compounds are of some importance for bone regeneration.

The Role of Cellular Metabolism in Maintaining the Function of the Dentine-Pulp Complex: A Narrative Review

The cellular metabolic processes ensure the physiological integrity of the dentine-pulp complex. Odontoblasts and odontoblast-like cells are responsible for the defence mechanisms in the form of tertiary dentine formation. In turn, the main defence reaction of the pulp is the development of inflammation, during which the metabolic and signalling pathways of the cells are significantly altered. The selected dental procedures, such as orthodontic treatment, resin infiltration, resin restorations or dental bleaching, can impact the cellular metabolism in the dental pulp. Among systemic metabolic diseases, diabetes mellitus causes the most consequences for the cellular metabolism of the dentine-pulp complex. Similarly, ageing processes present a proven effect on the metabolic functioning of the odontoblasts and the pulp cells. In the literature, several potential metabolic mediators demonstrating anti-inflammatory properties on inflamed dental pulp are mentioned. Moreover, the pulp stem cells exhibit the regenerative potential essential for maintaining the function of the dentine-pulp complex.

Fructus ligustri lucidi suppresses inflammation and restores the microbiome profile in murine colitis models

BACKGROUND

Ulcerative colitis (UC) is pathologically characterized by an inappropriate immune response to the gut commensal microbes accompanied by persistent epithelial barrier dysfunction, and its progression increases the susceptibility to colitis-associated cancer (CAC), as well as other complications. Fructus ligustri lucidi (FLL) has a long historical application in traditional Chinese medicine due to its various pharmacological effects, including antioxidation and anti-inflammation. The present study aimed to explore the molecular and cellular mechanisms of FLL in treating colitis.

METHODS

A high-performance liquid chromatography (HPLC) combined with ultraviolet (UV) was performed to validate the quality of FLL; Network pharmacology analysis and weighted gene co-expression network analysis (WGCNA) based on The Cancer Genome Atlas (TCGA) database predicted the therapeutic value of FLL against UC and CAC; 2% dextran sodium sulfate (DSS) was administered to mice to establish murine models of experimental colitis, and FLL was given for the next 14 days at different concentrations; 16S rRNA sequencing and untargeted metabolomics were performed on fecal samples to delineate the alteration in microbiome profile; Western blotting, flow cytometry, and immunocytochemistry experiments were conducted to confirm the predicted cellular mechanisms.

RESULTS

Network pharmacology analysis and WGCNA predicted that the targets of the FLL were associated with the progression of UC and the survival of patients with colorectal cancer by regulating tumor necrosis factor (TNF) and IL-17 signaling pathways, immune cell functions, responses to bacterial and reactive oxygen species (ROS), and cell proliferation. In vivo experiments corroborated that the high dose of FLL significantly attenuated the progression of experimental colitis by reversing the weight loss and bloody stool, reconstructing the integrity of colorectal epithelium, and suppressing the concentration of pro-inflammatory cytokines. Moreover, FLL treatment reduced the transition of macrophages (Mφs) to the proinflammatory phenotype and promoted Mφs-regulated wound healing, and suppressed the production of ROS in intestinal organoids (IOs) and crypts. 16S rRNA and untargeted metabolomics showed that the administration of FLL inhibited DSS-caused colonization of the potentially pathogenic gut microorganisms and reversed DSS-influenced metabolic profile.

CONCLUSION

FLL is a potent anti-colitis drug by suppressing inflammation and rescuing dysbiosis.

Botanicals and Oral Stem Cell Mediated Regeneration: A Paradigm Shift from Artificial to Biological Replacement

Stem cells are a well-known autologous pluripotent cell source, having excellent potential to develop into specialized cells, such as brain, skin, and bone marrow cells. The oral cavity is reported to be a rich source of multiple types of oral stem cells, including the dental pulp, mucosal soft tissues, periodontal ligament, and apical papilla. Oral stem cells were useful for both the regeneration of soft tissue components in the dental pulp and mineralized structure regeneration, such as bone or dentin, and can be a viable substitute for traditionally used bone marrow stem cells. In recent years, several studies have reported that plant extracts or compounds promoted the proliferation, differentiation, and survival of different oral stem cells. This review is carried out by following the PRISMA guidelines and focusing mainly on the effects of bioactive compounds on oral stem cell-mediated dental, bone, and neural regeneration. It is observed that in recent years studies were mainly focused on the utilization of oral stem cell-mediated regeneration of bone or dental mesenchymal cells, however, the utility of bioactive compounds on oral stem cell-mediated regeneration requires additional assessment beyond in vitro and in vivo studies, and requires more randomized clinical trials and case studies.

A novel hypoxic lncRNA, HRL-SC, promotes the proliferation and migration of human dental pulp stem cells through the PI3K/AKT signaling pathway

Background

Human dental pulp stem cells (hDPSCs) are critical for pulp generation. hDPSCs proliferate faster under hypoxia, but the mechanism by which long noncoding RNA (lncRNA) regulates this process is not fully understood.

Methods

Novel lncRNAs were obtained by reanalysis of transcriptome datasets from RNA-Seq under hypoxia compared with normoxia, and a differential expression analysis of target genes was performed. Bioinformatics analyses, including gene ontology analysis, Kyoto Encyclopedia of Genes and Genomes pathway analysis and gene set enrichment analysis, were used to understand the function of key novel lncRNAs. hDPSCs were isolated from dental pulp tissue. EdU and scratch wound healing assays were used to detect the proliferation and migration of hDPSCs. qRT-PCR was used to detect changes in the RNA expression of selected genes. RNA fluorescence in situ hybridization, small interfering RNA, qRT-PCR and Western blot analysis were used to explore the function of key novel lncRNAs.

Results

We identified 496 novel lncRNAs in hDPSCs under hypoxia, including 45 differentially expressed novel lncRNAs. Of these, we focused on a key novel lncRNA, which we designated HRL-SC (hypoxia-responsive lncRNA in stem cells). Functional annotation revealed that HRL-SC was associated with hypoxic conditions and the PI3K/AKT signaling pathway. HRL-SC was mainly located in the cytoplasm of hDPSCs and had stable high expression under hypoxia. Knockdown of HRL-SC inhibited the proliferation and migration of hDPSCs and the expression levels of PI3K/AKT-related marker proteins. Furthermore, the AKT activator SC79 partially offset the inhibitory effect caused by the knockdown, indicating that HRL-SC promoted hDPSCs through the PI3K/AKT signaling pathway.

Conclusions

Hypoxia-responsive lncRNA HRL-SC promotes the proliferation and migration of hDPSCs through the PI3K/AKT signaling pathway, and this understanding may facilitate the regenerative application of hDPSCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02970-5.