Anti-allergic effect of inotodiol, a lanostane triterpenoid from Chaga mushroom, via selective inhibition of mast cell function

Enzymatic synthesis and characterization of novel lipophilic inotodiol-oleic acid conjugates

In this study, we establish an efficient enzymatic approach for producing novel inotodiyl-oleates (IOs) from pure inotodiol and oleic acid to improve the properties of inotodiol. For the esterification between inotodiol and oleic acid, CALA and n-hexane were the optimal biocatalyst and solvents for forming IOs with 80.17% conversion yield. These IOs comprised two distinct monoesters, the C3 or C22 ester forms of inotodiol. Intriguingly, no diesters were detected. The IOs had a melting point of 53.48 °C, much lower than that of inotodiol (192.06 °C). The in vitro digestion rate of IOs (25-28%) was significantly (p < 0.05) lower than that of cholesteryl-oleate (60%). Additionally, IOs exhibited much lower in vivo absorption than inotodiol when orally administered using different formulations (p < 0.05). The results indicated that IOs were resistant to enzymatic digestion in the small intestine, which could be advantageous in targeting the large intestine for disease treatments.

Inotodiol ameliorates the progression of osteoarthritis: An in vitro and in vivo study

Osteoarthritis is a common chronic degenerative disease, of which the essence is the degenerative changes of bone and joint cartilage, involving damage in multiple structures such as bone, synovium and joints. In the mechanism of arthritis inflammation is closely related, and therefore the exploration to inhibit inflammatory mediators is crucial for the clinical prevention and treatment of osteoarthritis. Inotodiol is a lanostane triterpenoid isolated from Inonotus obliquus, which had been extensively reported to be an anti-inflammatory agent, but its effect on arthritis remains unknown. In this study, we firstly demonstrated that inotodiol significantly reduced IL-1β-induced chondrocyte injury and inhibited the release of inflammatory factors. At the same time, experiments in vivo showed that inotodiol could effectively improve the symptoms of joint injury in mice and reduce the area of cartilage destruction, indicating that inotodiol may be a potential therapeutic drug for osteoarthritis.

Preventive effects of inotodiol on polyinosinic-polycytidylic acid-induced inflammation in human dermal fibroblasts

Double-strand RNA(dsRNA), which can induce inflammation, can be generated by necrotic keratinocytes in the skin environment. As an analog of dsRNA, polyinosinic-polycytidylic acid (poly(I:C)) is used to induce inflammation via the Toll-like Receptor 3 (TLR3) signaling pathway. Inotodiol, isolated from Inonotus obliquus, known as Chaga mushroom, is a natural lanostane-type triterpenoid with significant pharmacological activity and notable anti-inflammatory effects. However, the functions of inotodiol on dsRNA-induced inflammation in human dermal fibroblast (HDFs) remains unclear. In this study, we evaluated the anti-inflammatory effects of inotodiol inflammation induced on by poly(I:C) in HDFs. After pre-treatment with inotodiol, poly (I:C) was used to induce inflammation. Subsequently, mRNA expression and protein secretion of inflammatory cytokines, as well as TLR3 signaling protein levels were assessed. Inflammatory cytokines IL-1β, IL-6, and TNF-α's increased mRNA expression by poly(I:C) in HDFs was significantly suppressed in the inotodiol pre-treatment group in a dose-dependent manner. A similar pattern was evaluated in the protein levels of these three cytokines. The inflammatory signals of TLR3 via p-IKK, p-p38, and NF-κB was reduced by inotodiol pre-treatment. Taken together, inotodiol possesses strong anti-inflammatory activity against poly(I:C)-induced inflammation in HDFs. Therefore, our findings support potential application of inotodiol as an effective anti-inflammatory agent in cosmetics.

Wild Mushrooms: A Hidden Treasure of Novel Bioactive Compounds

Secondary metabolites are hidden gems in mushrooms. Understanding these secondary metabolites' biological and pharmacological effects can be aided by identifying them. The purpose of this work was to profile the mycochemical components of the extracts of Auricularia auricula judae, Microporus xanthopus, Termitomyces umkowaani, Trametes elegans, and Trametes versicolor to comprehend their biological and pharmacological capabilities. Mushroom samples were collected from Kenya's Arabuko-Sokoke and Kakamega National Reserved Forests and identified using morphological and molecular techniques. Chloroform, 70% ethanol, and hot water solvents were used to extract the mycochemical components. Gas chromatography mass spectrometry (GC-MS) was used to analyze the chloroform, 70% ethanol, and hot water extracts of all the species examined. A total of 51 compounds were isolated from all extracts and classified as carboxylic acids, esters, phenols, fatty acids, alcohol, epoxides, aldehydes, fatty aldehydes, isoprenoid lipids, and steroids. Tetracosamethyl-cyclododecasiloxane (18.90%), oleic acid (72.90%), phenol, 2, 6-bis (1, 1-dimethylethyl)-4-methyl-, and methylcarbamate (26.56%) were all found in high concentrations in A. auricular judae, M. xanthopus, T. umkowaani, T. elegans, and T. versicolor, respectively. Fatty acids make up the majority of the compounds isolated from the T. elegans chloroform extract and the T. umkowaani 70% ethanol extract, respectively. Particularly, these fatty acids play crucial roles in the anti-inflammatory, hypocholesterolemic, anticancer, and antibiofilm formation activities. These bioactive elements indicate that the extracts of five wild mushrooms may be reliable sources of secondary metabolites for therapeutic development. Therefore, additional research is required to comprehend the usefulness of these chemicals in many functional areas and to improve the present understanding of macrofungi.

Inotodiol suppresses allergic inflammation in allergic rhinitis mice

BACKGROUND

Inotodiol has been proven to have antitumor, antiviral, anti-inflammatory, and antiallergic properties. This study investigated the immunomodulatory capability of inotodiol in allergic rhinitis (AR) mice.

METHODS

Forty BALB/c mice were divided into four groups, 10 mice each: control (CON), AR with phosphate-buffered saline (PBS) treatment (AR), inotodiol treatment (AR+Ino), and dexamethasone treatment (AR+Dex). Episodes of sneezing and nose rubbing were counted. Cytokines in nasal lavage fluid (NLF) and immunoglobulin in blood serum were measured. Nasal mucosae from each group were used for protein, reverse transcriptase-polymerase chain reaction (RT-PCR), and histological analyses. Splenocytes were cultured for evaluation of cytokine production in each group.

RESULTS

Symptoms of rubbing and sneezing improved in the group of AR+Ino and AR+Dex than in the AR. NLF in the AR+Ino and AR+Dex also showed a significant decrease in interleukin (IL)-5, IL-10, and IL-13 compared to the AR. In addition, the number of eosinophils, goblet cells, and mast cells were notably lower in the nasal mucosae of the AR+Ino and AR+Dex. IL-4 and IL-17A in the AR+Ino and AR+Dex groups were decreased compared to the AR. Chemokines related to mast cell degradation were also decreased in the AR+Ino and AR+Dex groups. Total immunoglobulin (Ig)E, specific IgE and ovalbumin (OVA)-specific IgG1, and histamine levels were also significantly lower in the AR+Ino and AR+Dex groups. IL-10 and IL-13 were notably increased in the splenocytes of the AR after OVA stimulation, whereas the other groups showed no change.

CONCLUSION

These results indicate inotodiol can help suppress allergic responses by immunomodulation activities.

Protective Effects of Lanostane Triterpenoids from Chaga Mushroom in Human Keratinocytes, HaCaT Cells, against Inflammatory and Oxidative Stresses

Inotodiol, a lanostane-type triterpenoid, and many phytochemicals from Chaga mushrooms have been investigated for various allergic diseases. However, the anti-aging and anti-inflammatory activities of inotodiol under different types of oxidative stress and the impact of inotodiol on collagen and hyaluronan synthesis have not been sufficiently studied. Lanostane triterpenoids-rich concentrate, which contained 10% inotodiol as major (inotodiol concentrate), was prepared from Chaga and compared with pure inotodiol in terms of anti-inflammatory activities on a human keratinocyte cell line, HaCaT cells, under various stimulations such as stimulation with ultraviolet (UV) B or tumor necrosis factor (TNF)-α. In stimulation with TNF-α, interleukin (IL)-1β, IL-6, and IL-8 genes were significantly repressed by 0.44~4.0 μg/mL of pure inotodiol. UVB irradiation induced the overexpression of pro-inflammatory cytokines, but those genes were significantly suppressed by pure inotodiol or inotodiol concentrate. Moreover, pure inotodiol/inotodiol concentrate could also modulate the synthesis of collagen and hyaluronic acid by controlling COL1A2 and HAS2/3 expression, which implies a crucial role for pure inotodiol/inotodiol concentrate in the prevention of skin aging. These results illuminate the anti-inflammatory and anti-aging effects of pure inotodiol/inotodiol concentrate, and it is highly conceivable that pure inotodiol and inotodiol concentrate could be promising natural bioactive substances to be incorporated in therapeutic and beautifying applications.

Inotodiol, an antiasthmatic agent with efficacy and safety, preferentially impairs membrane-proximal signaling for mast cell activation

While inhaled corticosteroids (ICSs) are the mainstay of asthma treatment, due to compliance, drug safety, and resistance issues, new medications to replace ICSs are in high demand. Inotodiol, a fungal triterpenoid, showed a unique immunosuppressive property with a preference for mast cells. It exerted a mast cell-stabilizing activity equally potent to dexamethasone in mouse anaphylaxis models when orally administered in a lipid-based formulation, upgrading bioavailability. However, it was four to over ten times less effective in suppressing other immune cell subsets, depending on the subsets, than dexamethasone showing invariably potent inhibition. Accordingly, inotodiol affected the membrane-proximal signaling for activating mast cell functions more profoundly than other subsets. Inotodiol also effectively prevented asthma exacerbation. Importantly, considering the no-observed-adverse-effect level of inotodiol was over 15 times higher than dexamethasone, its therapeutic index would be at least eight times better,implying that inotodiol is a viable option for replacing CSs in treating asthma.

Isolation, Physicochemical Characterization, and Biological Properties of Inotodiol, the Potent Pharmaceutical Oxysterol from Chaga Mushroom

Inotodiol, an oxysterol found only in Chaga mushroom, has received attention from the pharmaceutical industry due to its strong antioxidant and anti-allergic activities. However, the production of inotodiol is still challenging, and its fundamental properties have yet to be investigated. This study aims to develop an efficient method to produce high-purity inotodiol from Chaga mushroom. Then, pure inotodiol was used to assess its physicochemical properties and biological activities. By optimizing the solvent used for extraction and purification, a new method to produce inotodiol was developed with high purity (>97%) and purification yield (33.6%). Inotodiol exhibited a melting point (192.06 °C) much higher than lanosterol and cholesterol. However, the solubility of inotodiol in organic solvents was notably lower than those of the other two sterols. The difference in the hydroxyl group at C-22 of inotodiol has shown the distinctive physicochemical properties of inotodiol compared with cholesterol and lanosterol. Based on those findings, a nonionic surfactant-based delivery system for inotodiol was developed to improve its bioavailability. The inotodiol microemulsion prepared with 1-2% Tween-80 exhibited homogenous droplets with an acceptable diameter (354 to 217 nm) and encapsulation efficiency (85.6-86.9%). The pharmacokinetic analysis of inotodiol microemulsion in oral administration of 4.5 mg/kg exhibited AUC_0-24h = 341.81 (ng·h/mL), and C_max = 88.05 (ng/mL). Notably, when the dose increased from 4.5 to 8.0 mg/kg, the bioavailability of inotodiol decreased from 41.32% to 33.28%. In a mouse model of sepsis, the serum level of interleukin-6 significantly decreased, and the rectal temperature of mice was recovered in the inotodiol emulsion group, indicating that inotodiol microemulsion is an effective oral delivery method. These results could provide valuable information for applying inotodiol in functional food, cosmetic, and pharmaceutical industries.

Oleuropein Prevents OVA-Induced Food Allergy in Mice by Enhancing the Intestinal Epithelial Barrier and Remodeling the Intestinal Flora

SCOPE

This study assesses whether oleuropein prevents ovalbumin (OVA)-induced food allergy (FA) and investigates the underlying mechanisms.

METHODS AND RESULTS

A Balb/c FA mouse model is established and maintained for 7 weeks. The subjects are administered OVA by oral gavage to induce FA and supplemented with different oleuropein doses (1.00-20.00 mg kg^-1 per day) to evaluate its preventative efficacy. The results indicate that oleuropein effectively alleviates OVA-induced allergy symptoms and promotes temperature elevation in sensitized mice. The secretion of serology-specific OVA-immunoglobulin (Ig)E, OVA-IgG, and histamine is inhibited in the sensitized mice. Oleuropein dramatically upregulates the expression of intestinal tight junction (TJ) proteins, regenerating gene (Reg) IIIγ, and interleukin (IL)-22, enhancing the physical and biochemical barrier function of the intestinal epithelium. Additionally, oleuropein improves the immune homeostasis of the intestinal epithelium by affecting the function of mucosal mast cells and regulatory T (Treg) cells. The disordered intestinal flora of the sensitized mice also improves after oleuropein administration.

CONCLUSIONS

These findings suggest that oleuropein prevents FA by enhancing intestinal epithelial barrier function and improving immune homeostasis and intestinal flora in sensitized mice. Therefore, diets rich in oleuropein should be recommended for people with FA.

Evaluation of Toxicity and Efficacy of Inotodiol As an Anti-Inflammatory Agent Using Animal Model

Chaga mushroom (Inonotus obliquus) comprises polyphenolic compounds, triterpenoids, polysaccharides, and sterols. Among the triterpenoid components, inotodiol has been broadly examined because of its various biological activities. The purpose of this study is to examine inotodiol from a safety point of view and to present the potential possibilities of inotodiol for medical usage. From chaga mushroom extract, crude inotodiol (INO20) and pure inotodiol (INO95) were produced. Mice were treated with either INO20 or INO95 once daily using oral administration for repeated dose toxicity evaluation. Serum biochemistry parameters were analyzed, and the level of pro-inflammatory cytokines in the serum was quantified. In parallel, the effect of inotodiol on food allergic symptoms was investigated. Repeated administration of inotodiol did not show any mortality or abnormalities in organs. In food allergy studies, the symptoms of diarrhea were ameliorated by administration with INO95 and INO20. Furthermore, the level of MCPT-1 decreased by treatment with inotodiol. In this study, we demonstrated for the first time that inotodiol does not cause any detrimental effect by showing anti-allergic activities in vivo by inhibiting mast cell function. Our data highlight the potential to use inotodiol as an immune modulator for diseases related to inflammation.

A review of the pharmacological activities and protective effects of Inonotus obliquus triterpenoids in kidney diseases

Kidney diseases are common health problems worldwide. Various etiologies ultimately lead to the development of chronic kidney disease and end-stage renal disease. Natural compounds from herbs or medicinal plants are widely used for therapy and prevention of various ailments, among which is Inonotus obliquus. I. obliquus is rich in triterpenoids and the main active ingredients include betulinic acid, trametenolic acid, inotodiol, and ergosterol. New evidence suggests that I. obliquus triterpenes may be an effective drug for the treatment and protection of various kidney diseases. The aim of this review is to highlight the pharmacological activities and potential role of I. obliquus triterpenes in the kidney disease treatment and protection.

Bioactive components of mushrooms: Processing effects and health benefits

Mushrooms have been recognized for their culinary attributes for long and were relished in the most influential civilizations in history. Currently, they are the focus of renewed research because of their therapeutic abilities. Nutritional benefits from mushrooms are in the form of a significant source of essential proteins, dietary non-digestible carbohydrates, unsaturated fats, minerals, as well as various vitamins, which have enhanced its consumption, and also resulted in the development of various processed mushroom products. Mushrooms are also a crucial ingredient in traditional medicine for their healing potential and curative properties. The literature on the nutritional, nutraceutical, and therapeutic potential of mushrooms, and their use as functional foods for the maintenance of health was reviewed, and the available literature indicates the enormous potential of the bioactive compounds present in mushrooms. Future research should be focused on the development of processes to retain the mushroom bioactive components, and valorization of waste generated during processing. Further, the mechanisms of action of mushroom bioactive components should be studied in detail to delineate their diverse roles and functions in the prevention and treatment of several diseases.

Inotodiol From Inonotus obliquus Chaga Mushroom Induces Atypical Maturation in Dendritic Cells

Dendritic cells (DCs) have the ability to stimulate naïve T cells that coordinate subsequent adaptive response toward an inflammatory response or tolerance depending on the DC differentiation level. Inotodiol, a lanostane triterpenoid found in Inonotus obliquus (wild Chaga mushroom), is a natural compound with a wide range of biological activities. In this study, we investigated whether inotodiol promotes the maturation of bone marrow-derived DCs (BMDCs) and inotodiol-treated BMDCs induce T cell activation. Inotodiol increased the expression of surface maturation markers, including MHC-I, MHC-II, CD86, and CD40, on BMDCs without affecting the production of various cytokines, including TNF-α and IL-12p40 in these cells. T cells primed with inotodiol-treated BMDCs proliferated and produced IL-2, without producing other cytokines, including IL-12p40 and IFN-γ. Injection of inotodiol into mice induced maturation of splenic DCs and IL-2 production, and the administration of inotodiol and inotodiol-treated BMDCs induced the proliferation of adoptively transferred CD8⁺ T cells in vivo. The phosphatidylinositol-3-kinase inhibitor wortmannin abrogated the upregulation of Akt phosphorylation and CD86 and MHC-II expression induced by inotodiol. However, inotodiol failed to induce phosphorylation of the IκB kinase and degradation of IκB-α, and increased expression of CD86 induced by inotodiol was not blocked by an IκB kinase inhibitor. These results suggest that inotodiol induces a characteristic type of maturation in DCs through phosphatidylinositol-3-kinase activation independent of NF-κB, and inotodiol-treated DCs enhance T cell proliferation and IL-2 secretion.