Kunzea Ericoides (Kanuka) Leaf Extracts Show Moisturisation, Antioxidant, and UV Protection Effects in HaCaT Cells and Anti-melanogenesis Effects in B16F10 Cells

Kunzea ericoides (kanuka) products are well-known for their potent medicinal values in antioxidant and anti-inflammatory applications. The present study identified various compounds, such as chlorogenic acid, gallic acid, quercetin, and (E)-ferulic acid in the kanuka leaf extract, showing its potential use in maintaining skin health. The influence of kanuka leaf extract upon epidermal cells concerning cytotoxicity and in vitro activities of moisturisation, antioxidation, UV protection, and anti-melanogenesis effects were explored in the study. Kanuka leaf extract demonstrated significant promotion in the proliferation of HaCaT and B16F10 cells. After incubation with kanuka leaf extract, the content of ROS and DPPH in HaCaT was significantly decreased; at the same time, more SOD was produced. Furthermore, hyaluronidase-1 (HYAL-1) and HYAL-4 expressions were inhibited, while the aquaporin 3 (AQP-3) content was significantly increased in HaCaT. Kanuka leaf extract also inhibited the expressions of matrix metalloproteinases-1 (MMP-1) and MMP-14 in UV-induced HaCaT cells. In the B16F10 cell line, melanin and tyrosinase production were decreased under the presence of kanuka leaf extract, and the expressions of microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TYRP-1), and TYRP-2 were also inhibited. The study validated kanuka leaf extract as an effective natural product against photoaging and melanogenesis.

CTGF regulates mineralization in human mature chondrocyte by controlling Pit-1 and modulating ANK via the BMP/Smad signalling

OBJECTIVE

Connective tissue growth factor (CTGF) exhibits potent proliferative, differentiated, and mineralizing effects, and is believed to be contribute to cartilage mineralization in Osteoarthritis (OA). However, the underlying mechanism of chondrocyte mineralization induced by CTGF remains obscure. As a key regulator of mineral responses, type III phosphate transporter 1 (Pit-1) has been associated with the pathogenesis of articular mineralization. Therefore, the primary objective of this study was to investigate whether CTGF influences the development of mature chondrocyte mineralization and the underlying mechanisms governing such mineralization.

METHODS

The effect of Connective tissue growth factor (CTGF) on human C-28/I2 chondrocytes were investigated. The chondrocytes were treated with CTGF or related inhibitors, and transfected with Overexpression and siRNA transfection of Type III Phosphate Transporter 1(Pit-1). Subsequently, the cells were subjected to Alizarin red S staining, PiPer Phosphate Assay Kit, Alkaline Phosphatase Diethanolamine Activity Kit, ELISA, RT-PCR or Western blot analysis.

RESULTS

Stimulation with Connective tissue growth factor (CTGF) significantly upregulated the expression of the Type III Phosphate Transporter 1(Pit-1) and mineralization levels in chondrocytes through activation of α5β1 integrin and BMP/Samd1/5/8 signaling pathways. Furthermore, treatment with overexpressed Pit-1 markedly increased the expression of Multipass Transmembrane Ankylosis (ANK) transporter in the cells. The inhibitory effect of CTGF receptor blockade using α5β1 Integrin blocking antibody was demonstrated by significantly suppressed the expression of Pit-1 and ANK transporter, as well as chondrocyte mineralization.

CONCLUSIONS

Our data indicate that Connective tissue growth factor (CTGF) plays a critical role inchondrocyte mineralization, which is dependent on the expression of the Type III Phosphate Transporter 1(Pit-1) and Multipass Transmembrane Ankylosis (ANK) transporter. Consequently, inhibition of CTGF activity may represent a novel therapeutic approach for the management of Osteoarthritis (OA).

FABP4 knockdown suppresses inflammation, apoptosis and extracellular matrix degradation in IL-1β-induced chondrocytes by activating PPARγ to regulate the NF-κB signaling pathway

Osteoarthritis (OA) is a common degenerative disease that can lead to severe joint pain and loss of function, seriously threatening the health and normal life of patients. At present, the pathogenesis of OA remains to be clarified. Recent studies have shown that fatty acid-binding protein 4 (FABP4) is increased in the plasma and synovial fluid of patients with OA. However, the effect of FABP4 on OA is unclear. The present study established IL-1β-induced ATDC5 cells with FABP4 knockdown. Next, cell viability was detected with Cell Counting Kit-8 assay. The content of inflammatory factors, prostaglandin E2 and glycosaminoglycan (GAG) was detected via ELISA. The levels of reactive oxygen species (ROS) and superoxide dismutase (SOD) in cells were detected by using ROS and SOD kits, respectively. TUNEL staining was used to detect the apoptosis level. Western blotting was used to detect the expression levels of proteins. The results revealed that FABP4 was upregulated in IL-1β-induced ATDC5 cells. Knockdown of FABP4 increased cell viability, reduced inflammatory damage, oxidative stress and apoptosis in IL-1β-induced ATDC5 cells. Following FABP4 knockdown, the expression of matrix metalloproteinases (MMP3, MMP9 and MMP13) of IL-1β-induced ATDC5 cells was reduced, and the expression of GAG was promoted. FABP4 knockdown also inhibited the expression of NF-κB p65 and enhanced peroxisome proliferator-activated receptor (PPAR)γ expression. However, the presence of PPARγ inhibitor blocked the aforementioned effects of FABP4 on IL-1β-induced ATDC5 cells. In conclusion, FABP4 knockdown suppressed the inflammation, oxidative stress, apoptosis and extracellular matrix degradation of IL-1β-induced chondrocytes by activating PPARγ to inhibit the NF-κB signaling pathway.

Vitamin C: A stem cell promoter in cancer metastasis and immunotherapy

Vitamin C is an electron donor and is involved in a variety of biochemical reactions in stem cell and cancer stem cell, as well as collagen synthesis and the regulation of hypoxia-inducible factor synthesis, which two affect extracellular matrix remodelling and hence cancer metastasis. Specific doses of vitamin C can stop cancer cell glycolysis and block nitroso synthesis, indicating the potential of vitamin C in cancer treatment. Recent studies preliminary revealed Vitamin C enhance the cancer's immune response to anti PD-L1 therapy through multiple indirect approaches. Herein we reviewed the recent function of vitamin C for further research in sequential aspects of cancer stem cell, extracellular matrix remodeling, cancer metastasis and cancer immunotherapy.

The therapeutic effect of aucubin-supplemented hyaluronic acid on interleukin-1beta-stimulated human articular chondrocytes

BACKGROUND

Injection of exogenous hyaluronic acid (HA) into the joint capsule improves symptoms of early stage osteoarthritis (OA). However, reactive oxygen species degrade HA into small oligosaccharides that can elicit pro-inflammatory responses. Likewise, disturbance of the antioxidant enzyme system and generation of oxidative stress by pro-inflammatory cytokines worsen knee OA. Accordingly, we proposed the use of aucubin, an antioxidant and anti-inflammatory compound, as a versatile adjuvant to HA for treating OA.

METHODS

Primary human chondrocytes were cultured in media supplemented with aucubin in a series of concentrations (0, 0.01, 0.1, 1, and 10 μg/ml) to study dose-dependent toxicity. We then evaluated the therapeutic effects of HA (100 μg/ml) supplemented with aucubin (10 μg/ml) on interleukin-1 beta (IL-1β, 10 ng/ml)-stimulated chondrocytes.

RESULTS

The use of aucubin did not change cell viability or alter lactate dehydrogenase release to normal chondrocytes. Although the proliferation and sulfated glycosaminoglycan production were not affected, aucubin partially restored the hypertrophic transformation of chondrocytes. Relative to treatment with HA or aucubin alone, real-time PCR revealed that aucubin-supplemented HA down-regulated the mRNA levels of tumor necrosis factor-alpha (TNF-α), corrected collagen type 1 and aggrecan, and up-regulated tissue inhibitor of metalloproteinase 1. Moreover, ELISA testing also showed a reduced TNF-α production. Although superoxide dismutases activity was still distributed, aucubin restored total antioxidant capacity of IL-1β-stimulated chondrocytes. Western blotting further showed that aucubin inhibited cyclooxygenase-2 and regulated the nuclear factor (erythroid-derived 2)-like 2 pathway.

CONCLUSION

Aucubin can enhance the anti-catabolic and anti-inflammatory effects of HA on OA chondrocytes.

Initial effects of inflammation-related cytokines and signaling pathways on the pathogenesis of post-traumatic osteoarthritis

The main pathological change in post-traumatic osteoarthritis (PTOA) is cartilage degeneration, which is closely related to inflammation and oxidative stress. Inflammation can cause degeneration of articular cartilage. Cartilage degeneration can also stimulate the progression of inflammation. It has been found that inflammatory cytokines can participate in the pathological process of cartilage degeneration through multiple signaling pathways, mainly mitogen-activated protein kinase, nuclear transcription factor kappa B, and Wnt–β-catenin signal transduction pathways. This review aimed at exploring the relationship between PTOA and inflammation-related cytokines by introducing the role of proinflammatory cytokines in chondrocyte destruction and extracellular matrix degradation.