Persimmon leaf extract protects mice from atopic dermatitis by inhibiting T cell activation via regulation of the JNK pathway

The TAK1/JNK axis participates in adaptive immunity by promoting lymphocyte activation in Nile tilapia

The transforming growth factor beta-activated kinase 1 (TAK1)/c-Jun N-terminal kinase (JNK) axis is an essential MAPK upstream mediator and regulates immune signaling pathways. However, whether the TAK1/JNK axis harnesses the strength in regulation of signal transduction in early vertebrate adaptive immunity is unclear. In this study, by modeling on Nile tilapia (Oreochromis niloticus), we investigated the potential regulatory function of TAK1/JNK axis on lymphocyte-mediated adaptive immune response. Both OnTAK1 and OnJNK exhibited highly conserved sequences and structures relative to their counterparts in other vertebrates. Their mRNA was widely expressed in the immune-associated tissues, while phosphorylation levels in splenic lymphocytes were significantly enhanced on the 4th day post-infection by Edwardsiella piscicida. In addition, OnTAK1 and OnJNK were significantly up-regulated in transcriptional level after activation of lymphocytes in vitro by phorbol 12-myristate 13-acetate plus ionomycin (P + I) or PHA, accompanied by a predominant increase in phosphorylation level. More importantly, inhibition of OnTAK1 activity by specific inhibitor NG25 led to a significant decrease in the phosphorylation level of OnJNK. Furthermore, blocking the activity of OnJNK with specific inhibitor SP600125 resulted in a marked reduction in the expression of T-cell activation markers including IFN-γ, CD122, IL-2, and CD44 during PHA-induced T-cell activation. In summary, these findings indicated that the conserved TAK1/JNK axis in Nile tilapia was involved in adaptive immune responses by regulating the activation of lymphocytes. This study enriched the current knowledge of adaptive immunity in teleost and provided a new perspective for understanding the regulatory mechanism of fish immunity.

A Review: Pharmacological Effect of Natural Compounds in Diospyros kaki Leaves from the Perspective of Oxidative Stress

Oxidative stress is caused by an imbalance between reactive oxygen species and antioxidant levels. Current research suggests that oxidative stress is one of the key factors in the development of many chronic diseases, and it has been a concern for many years. Many natural compounds have been studied for their special free-radical-scavenging properties. The major chemical constituents of the leaves of Diospyros kaki are flavonoids and triterpenoids, both of which are potential antioxidants that can prevent damage caused by reactive oxygen species or reactive nitrogen species and ameliorate diseases associated with oxidative stress. In addition to the major constituents such as flavonoids and triterpenoids, the leaves of Diospyros kaki include compounds such as phenylpropanoids, alkaloids, phenolic acids, and terpenes. Studies have shown these compounds have certain antioxidant and neuroprotective activities. Experiments have shown that flavonoids or the extracts from the leaves of Diospyros kaki have a variety of good pharmacological activities, which could activate oxidative stress and mitochondrial apoptosis, inhibit the proliferation of human prostate cancer cells and induce apoptosis. It also could achieve the effect of anti-cancer cell proliferation and induce apoptosis by regulating oxidative stress. The main chemical substance of the leaves of Diospyros kaki regulating oxidative stress may be these multi-hydroxyl structure compounds. These natural products exhibit significant antioxidant activity and are an important basis for the leaves of Diospyros kaki to treat human diseases by regulating oxidative stress. This review summarizes the structural types of natural products in the leaves of Diospyros kaki and elaborates the mechanism of the leaves of Diospyros kaki in neuroprotection, anti-diabetes, renal protection, retinal degenerative diseases, and anti-cancer from a new perspective of oxidative stress, including how it supplements other pharmacological effects. The chemical constituents and pharmacological effects of the leaves of Diospyros kaki are summarized in this paper. The relationship between the chemical components in the leaves of Diospyros kaki and their pharmacological effects is summarized from the perspective of oxidative stress. This review provides a reference for the study of natural anti-oxidative stress drugs.

Efficacy and safety of persimmon leaf formulated with green tea and sophora fruit extracts (BLH308) on hair growth: A randomized, double-blind, placebo-controlled clinical trial

BACKGROUND

Recent research suggests that persimmon leaf extract (PLE) has an effect on inflammatory skin diseases. Previously, PLE is revealed to inhibit not only nitric oxide production but also inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels in mouse macrophages in vitro. Moreover, it significantly reduced IL-6 production and 5α-reductase expression in human follicle dermal papilla cells (HFDPCs). This study aimed to determine whether the PLE-containing BLH308 complex improves hair growth in clinical trials.

MATERIALS AND METHODS

A total of 88 participants were recruited, and were instructed to orally take BLH308 or the placebo twice a day for 24 weeks. The mean age of the test group was 38.52 ± 7.98 years and that of placebo group was 38.98 ± 8.80 years. The study was conducted for 24 weeks, and hair density, thickness, and gloss were evaluated. All participants completed a satisfaction survey questionnaire.

RESULTS

The test group showed significantly increased hair density and hair diameter at week 24 compared with the placebo group (p = 0.0015 and p = 0.0001, respectively). Although not statistically significant, the degree of gloss also showed higher improvement in the test group compared to the placebo group.

CONCLUSIONS

Our data demonstrated that oral consumption of the BLH308 complex containing PLE significantly increased hair density and thickness compared to the placebo group, showing its possible role in promoting hair growth.