Anti-inflammatory activities of Gardenia jasminoides extracts in retinal pigment epithelial cells and zebrafish embryos

Nobiletin derivative, 5-acetoxy-6,7,8,3',4'-pentamethoxyflavone, inhibits neuroinflammation through the inhibition of TLR4/MyD88/MAPK signaling pathways and STAT3 in microglia

OBJECTIVE

Microglia in the central nervous system regulate neuroinflammation that leads to a wide range of neuropathological alterations. The present study investigated the anti-neuroinflammatory properties of nobiletin (Nob) derivative, 5-acetoxy-6,7,8,3',4'-pentamethoxyflavone (5-Ac-Nob), in lipopolysaccharide (LPS)-activated BV2 microglia.

MATERIALS AND METHODS

By using the MTT assay, Griess method, flow cytometry, and enzyme-linked immunosorbent assay (ELISA), we determined the cell viability, the levels of nitric oxide (NO), reactive oxygen species (ROS), and pro-inflammatory factors (interleukin 1 beta; IL-1β, interleukin 6; IL-6, tumor necrosis factor alpha; TNF-α and prostaglandin E2; PGE2) in LPS-stimulated BV2 microglia. Toll-like receptor 4 (TLR4)-mediated myeloid differentiation primary response gene 88 (MyD88)/nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK) signaling pathway and signal transducer and activator of transcription 3 (STAT3) were measured by western blotting. Analysis of NO generation and mRNA of pro-inflammatory cytokines was confirmed in the zebrafish model.

RESULTS

5-Ac-Nob reduced cell death, the levels of NO, ROS, inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX-2), and pro-inflammatory factors in LPS-activated BV-2 microglial cells. TLR4-mediated MyD88/NF-κB and MAPK pathway (p38, ERK and JNK) after exposure to 5-Ac-Nob was also suppressed. Moreover, 5-Ac-Nob inhibited phosphorylated STAT3 proteins expression in LPS-induced BV-2 microglial cells. Furthermore, we confirmed that 5-Ac-Nob decreased LPS-induced NO generation and mRNA of pro-inflammatory cytokines in the zebrafish model.

CONCLUSIONS

Our findings suggest that 5-Ac-Nob represses neuroinflammatory responses by inhibiting TLR4-mediated signaling pathway and STAT3. As a result of these findings, 5-Ac-Nob has potential as an anti-inflammatory agent against microglia-mediated neuroinflammatory disorders.

Advanced quality assessment of Sanshishi (Gardenia jasminoides Ellis) and Kampo medicines using a monoclonal antibody against geniposide

Gardenia jasminoides Ellis, a plant widely used in traditional medicine, is known for its array of biological activities. A key bioactive compound, geniposide (GE), an iridoid glycoside, significantly contributes to the medicinal properties of the plant, with potential side effects. Thus, a reliable and efficient method for GE detection is required to ensure the quality of medicinal-grade G. jasminoides Ellis. This study developed such a method by first synthesizing GE-bovine serum albumin conjugates to function as immunizing agents in mice. This led to the production of a monoclonal antibody (mAb 3A6) against GE from the fusion of splenocytes from immunized mice with myeloma cells (P3U1), resulting in a hybridoma that produces mAb 3A6. Thereafter, we developed a mAb 3A6-based indirect competitive enzyme-linked immunosorbent assay (icELISA). The icELISA exhibited satisfactory sensitivity (0.391-12.5 μg/ml) and repeatability (coefficients of variation <10%). The accuracy of this method was validated through a spike-recovery assay (recovery of 101-112%). Furthermore, the icELISA was employed to determine the GE content in plant and Kampo medicine samples. The GE content positively correlated with those determined by high-performance liquid chromatography-ultraviolet. The proposed icELISA is rapid, cost-effective, and reliable for high-throughput GE detection in G. jasminoides Ellis, thereby contributing to the improved quality control and standardization of this valuable medicinal plant.

Unraveling the Red Sea soft coral Sarcophyton convolutum potentials against oxidative and inflammatory stresses in zebrafish

The Red Sea is one of the world's hotspots for biodiversity, and for marine natural products (MNPs) as well. These MNPs attract special interest for their capabilities to combat inflammatory and oxidative stress-related diseases, being some of the most serious health problems worldwide nowadays. The current study aimed to identify the bioactive ingredients of the Red Sea soft coral Sarcophyton convolutum, and to assess its protective potentials against oxidative and inflammatory stresses. Coral extract (CE) was analyzed using GC-MS and HPLC. In a protection trial, adult zebrafish were intraperitoneally injected with two doses of crab extract, i.e. 50 and 500 μg/fish in 1 % DMSO as a vehicle, then challenged with 30 μg L-1 of CuSO4 for 48 h. All groups, but the negative control one, were challenged with 30 μg L-1 of CuSO4. Total antioxidant activity, as well as mRNA levels of proinflammatory markers and antioxidant enzyme genes were measured. The results showed richness of S. convolutum extract with various bioactive ingredients, including phenolic compounds, flavonoids, alkanes, fatty acids, sesquiterpenes, and pheromone-like substances. CuSO4 significantly induced the expected signals of inflammatory and oxidative stress, reducing both the antioxidant activity and increasing proinflammatory marker genes. However, CE, especially the low dose, showed significant capability to reduce proinflammatory markers and elevating the total antioxidant activity. Therefore, we concluded that S. convolutum can be a promising source for future efforts of drug discovery and a wide spectrum of pharmaceutical products.

A comprehensive review of ethnopharmacology, chemical constituents, pharmacological effects, pharmacokinetics, toxicology, and quality control of gardeniae fructus

ETHNOPHARMACOLOGICAL RELEVANCE

Gardeniae Fructus (GF), the desiccative mature fruitage of Gardenia jasminoides J. Ellis (G. jasminoides), belongs to the Rubiaceae family. It has abundant medicinal value, such as purging fire and eliminating annoyance, clearing heat and diuresis, cooling blood, and detoxifying. GF is usually used in combination with other drugs to treat diseases such as fever and jaundice in damp heat syndrome in traditional Chinese medicines (TCMs) clinical practice.

THE AIM OF THE REVIEW

This review comprehensively summarizes the research progress in botany, traditional medical use, processing method, phytochemistry, pharmacological activity, quality control, pharmacokinetics, and toxicology, which aims to provide a scientific basis for the rational application and future research of GF.

MATERIALS AND METHODS

ScienceDirect, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Embase, Scopus etc. databases were retrieved to gain the comprehensive information of GF.

RESULTS

At present, more than 215 compounds were isolated and identified from GF, including iridoids, diterpenes, triterpenoids, flavonoids, organic esters, and so on. The traditional application of GF mainly focused on clearing heat and detoxification. Pharmacological studies proved that GF had anti-inflammatory, antioxidation, antifatigue, antithrombotic, liver and gallbladder protection, and other pharmacological effects. In addition, many improved processing methods can alleviate the side effects and toxic reactions caused by long-term use of GF, so controlling its quality through multi-component content measurement has become an important means of research.

CONCLUSION

GF has a wide range of applications, the mechanisms by which some effective substances exert their pharmacological effects have not been clearly explained due to the complexity and diversity of its components. This review systematically elaborates on the traditional medical use, processing method, phytochemistry, pharmacological activity, quality control, and toxicology of GF, and it is expected to become a candidate drug for treating diseases, such as depression, pancreatitis, alcoholic or non-alcoholic fatty liver.

Effect of Gardenia Pomace Supplementation on Growth Performance, Blood Metabolites, Immune and Antioxidant Indices, and Meat Quality in Xiangcun Pigs

To investigate the effect of gardenia pomace (GP) as an unconventional feed of antioxidants, 180 Xiangcun pigs were randomly divided into 3 groups during the finishing period, with 6 replicates per group and 10 pigs per replicate. During the 47-day feeding period, the pigs were fed either a control diet based on corn and soybean meal (control group), or the control diet added with 50 g/kg or 100 g/kg GP (groups GP5 and GP10, respectively). Feed and water were provided ad libitum. One pig per replicate was slaughtered and sampled. The effects on growth performance, meat quality, digestibility, metabolism, and immunity and antioxidant properties of the pigs were investigated. The results showed that GP had no significant effect on the growth performance of Xiangcun pigs. Compared with the control group, the digestibility of crude ash, phosphorus, and crude fibre of pigs in the GP groups improved (p < 0.01), and the content of inosinic acid in the longissimus dorsi muscle increased (p < 0.05). The addition of GP to the diet significantly increased superoxide dismutase (SOD) levels in the liver and spleen, and glutathione peroxidase (GSH-Px) activity in the longissimus dorsi muscle and spleen (p < 0.05). Additionally, it significantly reduced the contents of malondialdehyde (MDA) in the liver and spleen (p < 0.05). The GP5 group had a higher inosinic acid content in the longissimus dorsi and lower levels of the inflammatory factor interleukin-2 and interleukin-8 than those in the other groups (p < 0.05). The GP10 group had a higher IgA level (p < 0.05). Adding different proportions of GP to the diet improved the a* and b* of the longissimus dorsi muscles of Xiangcun pigs (p < 0.05). In summary, GP, as an unconventional feed, improved the apparent digestibility of the diet and body antioxidant capacity in Xiangcun pigs during the finishing period and did not negatively affect the growth performance or meat quality.

Gardenia jasminoides Attenuates Allergic Rhinitis-Induced Inflammation by Inhibiting Periostin Production

Allergic rhinitis (AR) is a chronic inflammatory condition affecting the nasal mucosa of the upper airways. Herein, we investigated the effects of extracts from Gardenia jasminoides (GJ), a traditional herbal medicine with anti-inflammatory properties, on AR-associated inflammatory responses that cause epithelial damage. We investigated the inhibitory effects of water- and ethanol-extracted GJ (GJW and GJE, respectively) in an ovalbumin-induced AR mouse model and in splenocytes, differentiated Th2 cells, and primary human nasal epithelial cells (HNEpCs). Administering GJW and GJE to ovalbumin-induced AR mice improved clinical symptoms including behavior (sneezing and rubbing), serum cytokine levels, immune cell counts, and histopathological marker levels. Treatment with GJW and GJE reduced the secretion of Th2 cytokines in Th2 cells isolated and differentiated from the splenocytes of these mice. To investigate the underlying molecular mechanisms of AR, we treated IL-4/IL-13-stimulated HNEpCs with GJW and GJE; we found that these extracts significantly reduced the production of mitochondrial reactive oxygen species via the uncoupling protein-2 and periostin, a biomarker of the Th2 inflammatory response. Our results suggest that GJ extracts may potentially serve as therapeutic agents to improve the symptoms of AR by regulating the Th2 inflammatory response of the nasal epithelium.