Therapeutic potential and mechanism of Dendrobium officinale polysaccharides on cigarette smoke-induced airway inflammation in rat

Dendrobium officinale Kimura et Migo polysaccharide ameliorated DNFB-induced atopic dermatitis in mice associated with suppressing MAPK/NF-κB/STAT3 signaling pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium officinale Kimura et Migo as a valuable Chinese medicine has been used in China for more than 2000 years. Its main active components, polysaccharide (DOP), has been reported to have various pharmacological effects, including anti-inflammatory, antioxidant and alleviating AD effects. However, the precise mechanism underlying its therapeutic effect in AD remains largely unclear.

AIM OF THE STUDY

The present study sought to assess the efficacy of DOP and elucidate its intricate mechanisms in ameliorating DNFB-induced AD.

MATERIALS AND METHODS

Mice were sensitized with DNFB and treated with DOP application for 14 days. Treatment effects were assessed using dermatitis scores, ear thickness and scratching frequency. Epidermal thickness, mast cells and CD4+ T cells infiltration were detected by using H&E, toluidine blue staining and immunofluorescence staining respectively. Serum histamine (HIS), immunoglobulin E (IgE), thymic stromal lymphopoietin (TSLP), skin SOD, MDA, GHS, CAT, inflammatory cytokines (TNF-α, IFN-γ, IL-1β, IL-4, IL-5, IL-13) and chemokine (MIP-α, MDC, MCP-1) levels were quantify by ELISA and immunohistochemistry. Additionally, qPCR and Western blot analyses were performed to assess genes and proteins expression associated with MAPK/NF-κB/STAT3 signaling pathway.

RESULTS

The results indicated that DOP effectively mitigated AD-like skin lesions in mice through multiple pathways. It reduced epidermal thickness, ear thickness and scratching frequency in AD mice. Additionally, DOP mitigated inflammatory responses by decreasing the levels of inflammatory factors, as well as reducing serum levels of IgE, HIS, and TSLP. Moreover, DOP inhibited infiltration of mast cells and CD4+ T cells, suppressed the expression of skin chemokines such as MDC, MCP-1, and MIP-α, and enhanced filaggrin content in AD mice. Furthermore, DOP significantly boosted antioxidant capacity, as well as significantly reduced the expression of JAK1, STAT3, NF-κB p65, IκBα, ERK1/2, and p38 proteins and phosphorylated proteins such as p-JAK1, p-STAT3, p-NF-κB p65, p-IκBα, p-ERK1/2, and p-p38.

CONCLUSIONS

These findings suggested that DOP has significant anti-AD activity, primarily through reducing inflammatory responses, improving antioxidant capacity, repairing the skin barrier, and down-regulating key genes and proteins in MAPK/NF-κB/STAT3 signaling pathway, and that this study may provide valuable insights into the development of innovative therapies for the treatment of AD.

Polysaccharides, the active component of Dendrobiumofficinale flower, ameliorates chronic pharyngitis in rats via TLR4/NF-κb pathway regulation

ETHNOPHARMACOLOGICAL RELEVANCE

Chronic pharyngitis persistently afflicts a large population and accounts for approximately one-third of otolaryngology patients. Currently, the treatment of CP remains controversial because of the poor outcomes. Dendrobium officinale is a well-used "Yin-nourishing" traditional Chinese medicinal and edible herb used for thousands of years in China. The flowers of D. officinale are often used in folk of China to make tea for voice protection on and throat clearing.

AIM OF THE STUDY

This study was to evaluate beneficial effects of polysaccharides from D. officinale flower (DOFP) on CP and its potential mechanisms.

METHODS

Chemical characterization of DOFP, including polysaccharide content and monosaccharide composition, structural characterization using Fourier transform infrared spectroscopy were performed. A CP model was established in rats by administering a mixture of Chinese Baijiu and chili pepper liquid, combined with low-concentration ammonia spraying. The general states, amount of oral secretion, and apparent state of the pharynx of CP rats were observed during the period of DOFP administration. Furthermore, hemorheological parameters were measured using an automatic hematology analyzer. The levels of tumor necrosis factor-α (TNF-α), interleukin 1β (1L-1β), lipopolysaccharide (LPS), and D-lactate (D-LA) in the serum were measured by enzyme-linked immunosorbent assay. Morphological changes in the pharynx and colon were observed by hematoxylin-eosin staining. The expression of nuclear factor-κB p65 (NF-κB p65), p-NF-κB p65, cyclooxygenase-2 (COX-2), interleukin 1β（IL-1β）and mucin 5AC (MUC5AC) in the pharynx,Claudin-1, Occludin, and interleukin 6 (IL-6) in the colon was detected by immunohistochemistry and Western Blot. The mRNA expression of TLR4, COX-2, and IL-1β in the pharynx were determined using reverse transcription quantitative real-time PCR.

RESULTS

In this study, DOFP with a total polysaccharide content of 71.44% and a composition of D-mannose, galacturonic acid, glucose, galactose, and arabinose in a molar ratio of 3.95:2.19:1.00:0.74:1.30, was isolated from the flowers of D. officinale. DOFP improved the general state and exhibited significant effects on reducing oral secretion, alleviating pharyngeal injury, suppressing inflammatory cell infiltration in the pharynx, decreasing the serum levels of TNF-α and IL-1β, and reducing the number of white blood cells and lymphocytes in the model rats. Moreover, the expressions of TLR4, p-NF-κB p65, COX-2, IL-1β and MUC5AC in the pharynx of model rats were obviously inhibited. In addition, the levels of LPS, D-LA in the serum and the protein expression of IL-6 in the colon were downregulated when the protein expression of Occludin and Claudin-1 in the colon were upregulated.

CONCLUSIONS

DOFP exerts significant ameliorating effects on CP and it likely acts by inhibiting LPS/TLR4-associated inflammatory mediator activation and reducing excessive secretion of mucus by repairing the intestinal barrier in CP rats.

Structure characteristics, protective effect and mechanisms of ethanol-fractional polysaccharides from Dendrobium officinale on acute ethanol-induced gastritis

Gastritis is a common disease characterized by gastric ulcers and severe bleeding. Excessive daily alcohol consumption can cause acute gastritis, impacting individuals' quality of life. This study aims to explore the protective effects of different ethanol-fractional polysaccharides of Dendrobium officinale (EPDO) on acute alcohol-induced gastric injury in vivo. Results showed that EPDO-80, identified as a β-glucan, exhibited significant anti-inflammatory properties in pathology. It could reduce the area of gastric mucosal injury and cell infiltration. EPDO-80 had a dose-effect relationship in reducing the levels of malondialdehyde and cyclooxygenase-2 and decreasing the levels of inflammation mediators such as tumor necrosis factor α. More extensively, EPDO-80 could inhibit the activation of the TNFR/IκB/NF-κB signaling pathway, reducing the production of TNF-α mRNA and cell apoptosis in organs. Conversely, EPDO-80 could promote changes in the gut microbiota structure. These findings suggest that EPDO-80 could have great potential in limiting oxidative stress and inflammation mediated by inhibiting the NF-κB signaling pathway, which is highly related to its β-glucan structure and functions in gut microbiota.

Critical review on the research of chemical structure, bioactivities, and mechanism of actions of Dendrobium officinale polysaccharide

Dendrobium officinale (Tie-Pi-Shi-Hu) is a precious traditional Chinese medicine (TCM). The principal active components are polysaccharides (DOP), which have a high potency in therapeutic applications. However, limitations in structure analysis and underlying mechanism investigation impede its further research. This review systemically and critically summarises current understanding in both areas, and points out the influence of starch impurities and the role of gut microbiota in DOP research. As challenges faced in studying natural polysaccharide investigations are common, this review contributes to a broader understanding of polysaccharides beyond DOP.

Dendrobium officinale Polysaccharide (DOP) inhibits cell hyperproliferation, inflammation and oxidative stress to improve keratinocyte psoriasis-like state

PURPOSE

Psoriasis is a skin disease characterized by excessive proliferation, inflammation and oxidative stress in keratinocytes. The present study aimed to investigate the therapeutic effects of Dendrobium officinale polysaccharide (DOP) on keratinocyte psoriasis-like models.

METHODS

The HaCaT keratinocyte inflammation models were induced by interleukin (IL)-22 or lipopolysaccharide (LPS), respectively, and oxidative stress damage within cells was elicited by H2O2 and treated using DOP. CCK-8 and EdU were carried out to detect cell proliferation. ELISA, qRT-PCR, and Western blot were conducted to measure the expression of pro-inflammatory cytokines IL17A, IL-23, IL1β, tumor necrosis factor alpha (TNF-α), and IL-6. Reactive oxygen species (ROS) level in keratinocytes was detected by flow cytometry. Cell proliferation-associated proteins (PCNA, Ki67, Cyclin D1) and pathway proteins (p-AKT and AKT), and oxidative stress marker proteins (Nrf-2, CAT, SOD1) were detected by Western blot.

RESULT

DOP did not affect the proliferation of normal keratinocytes, but DOP was able to inhibit the proliferative activity of IL-22-induced overproliferating keratinocytes and suppress the expression of proliferation-related factors PCNA, Ki67, and Cyclin D1 as well as the proliferation pathway p-AKT. In addition, DOP treatment was able to inhibit IL-22 and LPS-induced inflammation and H2O2-induced oxidative stress, including the expression of IL17A, IL-23, IL1β, TNF-α, IL-6, and IL1β, as well as the expression levels of intracellular ROS levels and cellular oxidative stress-related indicators SOD, MDA, CAT, Nrf-2 and SOD1.

CONCLUSION

DOP inhibits keratinocyte hyperproliferation, inflammation and oxidative stress to improve the keratinocyte psoriasis-like state.

Dendrobium officinale Polysaccharides as a Natural Functional Component for Acetic-Acid-Induced Gastric Ulcers in Rats

Dendrobium officinale is an important edible and medicinal plant, with the Dendrobium officinale polysaccharide (DOP) being its primary active constituent, known for its diverse biological activities. In this study, DOP was extracted and characterized for its structural properties. The potential of DOP to ameliorate gastric ulcers (GUs) was investigated using an acetic-acid-induced GU model in rats. The results demonstrated that DOP exerted a multifaceted protective effect against GU, mitigating the deleterious impact on food intake and body weight in rats. DOP exhibited its protective action by attenuating cellular damage attributed to oxidative stress and inflammatory reactions mediated by enhanced activities of SOD, GSH, and GSH-PX, coupled with a downregulation in the expression of pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α. Furthermore, DOP effectively inhibited apoptosis in gastric mucosa cells of acetic-acid-induced GU rat models and facilitated the self-repair of damaged tissues. Remarkably, the DOP-200 and DOP-400 groups outperformed omeprazole in reducing the expression of IL-6 and malondialdehyde (MDA) in tissues, as well as IL-1β, IL-6, and TNF-α in serum. These groups also exhibited an improved expression of SOD in tissues and SOD, GSH, and GSH-PX in serum. A Western blot analysis of gastric mucosa demonstrated that the DOP-200 and DOP-400 groups significantly reduced the expression of NF-κBp65, phosphorylated NF-κBp65, FoxO3a, and Bim. The observed antagonism to GU appeared to be associated with the NF-κB cell pathway. Additionally, qRT-PCR results indicate that DOP reduced the mRNA transcription levels of IL-6, and TNF-α, which shows that the healing of GU is related to the reduction in the inflammatory reaction by DOP. However, the expression of EGF and VEGF decreased, suggesting that the mechanism of DOP inhibiting GU may not be directly related to EGF and VEGF, or there is an uncertain competitive relationship between them, so further research is needed.

Dendrobium officinale Kimura & Migo polysaccharide and its multilayer emulsion protect skin photoaging

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium officinale Kimura & Migo is traditionally used to treat skin diseases, gastrointestinal diseases, and other diseases. Dendrobium officinale polysaccharides (DOP) are the main component of Dendrobium officinale that accounts for its bioactivity, which shows a variety of effects such as moisturizing, antioxidant and anti-fatigue. However, there is no comprehensive study on the effect of DOP on skin photoaging combined with in vitro and in vivo models, and its specific mechanism is still unclear.

AIM OF THE STUDY

Our study aimed to explore the effect and underlying mechanism of DOP on skin photoaging, as well as to improve the stability and transdermal absorption of DOP.

MATERIALS AND METHODS

DOP was extracted, purified and structurally characterized. In vitro HaCaT cell photoaging model was used to examine the photoprotection effect of DOP. Cell viability was detected by CCK-8; Intracellular reactive oxygen species were determined by DCFH-DA; DNA damage, cell apoptosis and cell cycle arrest were examined by flow cytocytometry. For autophagy flux detection, the adenovirus loaded with mRFP-GFP-LC3 was introduced into cells. Further, to enhance the stability and absorption of DOP, we designed and prepared the W/O/W type DOP multilayer emulsions (ME) by a two-step emulsification method. The emulsion stability, drug loading and encapsulation rate, DOP stability and DOP transdermal rate were detected. In vivo photoaging animal model was applied to compare the difference of photoaging protection effect between DOP solution and DOP ME. Specifically, skin appearance, histological change, antioxidant system, proinflammatory indicators, matrix metalloproteinases and autophagy level of skin tissues were examined and compared.

RESULTS

The results showed that DOP achieve photoaging protection by inhibiting oxidative stress, alleviating cell cycle arrest and apoptosis, and enhancing autophagy flux in photoaged HaCaT cells. The W/O/W type DOP multilayer emulsion (ME) with high encapsulation rate and strong stability was found to significantly improve the stability and transdermal absorption of DOP. In addition, our results showed that DOP (ME) remarkably improved skin condition of photoaged mice. Specifically, DOP (ME) enhanced the expression of antioxidant enzymes and autophagy and decreased the levels of pro-inflammatory factors and matrix metalloproteinases in the skin of photoaged mice as compared with DOP solution.

CONCLUSIONS

In conclusion, DOP was effective in improving skin photoaging, and the DOP multilayer emulsion we designed enhanced the stability and skin absorption of DOP, boosting DOP's protective effect against photoaging.

Structure, Health Benefits, Mechanisms, and Gut Microbiota of Dendrobium officinale Polysaccharides: A Review

Dendrobium officinale polysaccharides (DOPs) are important active polysaccharides found in Dendrobium officinale, which is commonly used as a conventional food or herbal medicine and is well known in China. DOPs can influence the composition of the gut microbiota and the degradation capacity of these symbiotic bacteria, which in turn may determine the efficacy of dietary interventions. However, the necessary analysis of the relationship between DOPs and the gut microbiota is lacking. In this review, we summarize the extraction, structure, health benefits, and related mechanisms of DOPs, construct the DOPs-host axis, and propose that DOPs are potential prebiotics, mainly composed of 1,4-β-D-mannose, 1,4-β-D-glucose, and O-acetate groups, which induce an increase in the abundance of gut microbiota such as Lactobacillus, Bifidobacterium, Akkermansia, Bacteroides, and Prevotella. In addition, we found that when exposed to DOPs with different structural properties, the gut microbiota may exhibit different diversity and composition and provide health benefits, such as metabolism regulations, inflammation modulation, immunity moderation, and cancer intervention. This may contribute to facilitating the development of functional foods and health products to improve human health.

Dendrocandin U from Dendrobium officinale Kimura et Migo Inhibits M1 Polarization in Alveolar Macrophage by Suppressing NF-κB Signaling Pathway

Dendrobium officinale Kimura et Migo is a valuable and homologous medicine and food traditional Chinese medicine. Currently there are few studies on the anti-inflammatory activity of lipophilic components. The aim of this study was to explore the anti-inflammatory effect and mechanism of the lipophilic compounds in Dendrobium officinale. Six compounds were isolated and identified, including three bibenzyl compounds, dendrocandin U, dendronbibisline B, erianin, and three lignans, (-)-syringaresinol, (+)-syringaresinol-O-β-D-glucopyranoside, 5-methoxy-(+)-isolariciresinol. Among them, dendronbibisline B and 5-methoxy-(+)-isolariciresinol were isolated from Dendrobium officinale for the first time. Besides, we found dendrocandin U, dendronbibisline B and (-)-syringaresinol exhibited the anti-inflammation to inhibit nitric oxide secretion induced by lipopolysaccharide (LPS)/interferon (IFN-γ) in MH-S cells. Furthermore, dendrocandin U could inhibit the expression of tumor necrosis factor-α (TNF-α), Cluster of Differentiation 86 (CD86), and reduce inflammatory morphological changes of macrophages. Meanwhile, we confirmed that the anti-inflammation mechanism of dendrocandin U was to inhibit M1 polarization by suppressing toll-like receptor 4 (TLR4)/recombinant myeloid differentiation factor 88 (MyD88)/nuclear factor kappa B (NF-κB) signaling pathway. In this paper, dendrocandin U with significant anti-inflammatory activity was found from Dendrobium officinale, which could provide a basis for the study of its anti-inflammatory drugs.

Nanoassemblies from the aqueous extract of roasted coffee beans modulate the behavioral and molecular effects of smoking withdrawal-induced anxiety in female rats

Antioxidant-rich plant extracts have demonstrated tremendous value as inflammatory modulators and as nanomaterial precursors. Chronic cigarette smoking alters neurotransmitter systems, particularly the glutamatergic system, and produces neuroinflammation. This study aimed to investigate the behavioral and molecular correlates of cigarette smoking withdrawal-induced anxiety-like behavior in rats, and whether these effects could be mitigated by the administration of antioxidant nanoassemblies prepared by spontaneous oxidation of dark-roasted Arabica coffee bean aqueous extracts. Four experimental groups of female Sprague-Dawley rats were randomly assigned to: (i) a control group that was only exposed to room air, (ii) a COF group that was administered 20 mg/kg of the coffee nanoassemblies by oral gavage, (iii) a SMOK group that was exposed to cigarette smoke and was given an oral gavage of distilled water, (iv) and a SMOK + COF group that was exposed to cigarette smoke and administered 20 mg/kg of the coffee nanoassemblies. Animals were exposed to cigarette smoke for 2 h per day, five days per week, with a 2-day withdrawal period each week. At the end of the 4th week, rats began receiving either distilled water or the coffee nanoassemblies before being exposed to cigarette smoke for 21 additional days. Weekly behavioral tests revealed that cigarette smoking withdrawal exacerbated anxiety, while the administration of the coffee nanoassemblies reduced this effect. The effect of cigarette smoking on astroglial glutamate transporters and nuclear factor kappa B (NF-κB) expression in brain subregions was also measured. Smoking reduced the relative mRNA and protein levels of the glutamate transporter 1 (GLT-1) and the cystine/glutamate antiporter (xCT), and increased the levels of NF-κB, but these effects were attenuated by the coffee nanoassemblies. Thus, administration of the antioxidant nanoassemblies decreased the negative effects of cigarette smoke, which included neuroinflammation, changes in glutamate transporters' expression, and a rise in anxiety-like behavior.

Long-term e-cigarette aerosol exposure causes pulmonary emphysema in adult female and male mice

This study aimed to evaluate long-term exposure to conventional cigarette smoke (CC) and electronic cigarette (EC) aerosol in adult male and female C57BL/6 mice. Forty-eight C57BL/6 mice were used, male (n = 24) and female (n = 24), both were divided into three groups: control, CC and EC. The CC and EC groups were exposed to cigarette smoke or electronic cigarette aerosol, respectively, 3 times a day for 60 consecutive days. Afterwards, they were maintained for 60 days without exposure to cigarettes or electronic cigarette aerosol. Both cigarettes promoted an influx of inflammatory cells to the lung in males and females. All animals exposed to CC and EC showed an increase in lipid peroxidation and protein oxidation. There was an increase of IL-6 in males and females exposed to EC. The IL-13 levels were higher in the females exposed to EC and CC. Both sexes exposed to EC and CC presented tissue damage characterized by septal destruction and increased alveolar spaces compared to control. Our results demonstrated that exposure to CC and EC induced pulmonary emphysema in both sexes, and females seem to be more susceptible to EC.

Acute Outcomes of Cigarette Smoke and Electronic Cigarette Aerosol Inhalation in a Murine Model

Cigarette smoking throughout life causes serious health issues in the lungs. The electronic cigarette (E-Cig) use increased, since it was first introduced in the world. This research work compared the short-term exposure consequences to e-cigarette vapor and cigarette smoke in male mice. Forty-five C57BL/6 mice were randomized into control (C) in an ambient air exposition cigarette smoke (CS) and aerosol electronic cigarette (EC), both were exposed to 120 puffs, 3 times/day during five days. Then, in the experimental protocol, the euthanized mice had their tissues removed for analysis. Our study showed that CS and EC resulted in higher cell influx into the airways, and an increase in macrophage counts in CS (209.25 ± 7.41) and EC (220.32 ± 8.15) when compared to C (108.40 ± 4.49) (p < 0.0001). The CS (1.92 ± 0.23) displayed a higher pulmonary lipid peroxidation as opposed to C (0.93 ± 0.06) and EC (1.23 ± 0.17) (p < 0.05). The EC (282.30 ± 25.68) and CS (368.50 ± 38.05) promoted increased levels of interleukin 17 when compared to C (177.20 ± 10.49) (p < 0.05). The EC developed shifts in lung histoarchitecture, characterized by a higher volume density in the alveolar air space (60.21; 55.00-65.83) related to C (51.25; 18.75-68.75) and CS (50.26; 43.75-62.08) (p =0.002). The EC (185.6 ± 9.01) presented a higher respiratory rate related to CS (133.6 ± 10.2) (p < 0.002). Therefore, our findings demonstrated that the short-term exposure to e-cig promoted more acute inflammation comparing to cigarette smoke in the ventilatory parameters of the animals.

Dendrobium officinale polysaccharide inhibits vascular calcification via anti-inflammatory and anti-apoptotic effects in chronic kidney disease

Vascular calcification is very common in patients with chronic kidney disease (CKD), but so far, there is no effective treatment. Dendrobium officinale polysaccharide (DOP), a natural component of Chinese herbal medicine, has been shown to exert anti-inflammatory and anti-apoptotic activity. Inflammation and apoptosis play an essential role in the progression of vascular calcification. However, the exact role and molecular mechanisms of DOP in vascular calcification remain unclear. In this study, we investigated the effects of DOP on vascular calcification using vascular smooth muscle cells (VSMCs), arterial rings, and CKD rats. Alizarin red staining and gene expression analysis revealed that DOP inhibited calcification and osteogenic differentiation of rat VSMCs in a dose-dependent manner. Similarly, ex vivo studies revealed that DOP inhibited the calcification of rat arterial rings. Furthermore, the administration of DOP alleviated vascular calcification in CKD rats. Moreover, DOP treatment suppressed VSMC inflammation and apoptosis. Finally, DOP treatment upregulated mRNA and protein levels of heme oxygenase-1 (HMOX-1); both pharmacological inhibition of HMOX-1 by the HMOX-1 inhibitor zinc protoporphyrin-9ZnPP9 and knockdown of HMOX-1 by siRNA markedly abrogated the suppression of inflammation and osteogenic differentiation of VSMCs by DOP. Collectively, these results suggest that DOP alleviates vascular calcification in CKD by suppressing apoptosis and inflammation via HMOX-1 activation. These results may provide a promising treatment for vascular calcification in CKD.

LncRNA-CCAT1/miR-152-3p is involved in CSE-induced inflammation in HBE cells via regulating ERK signaling pathway

Emerging studies have noted that dysregulated long non-coding RNAs (lncRNAs) are implicated in the pathological processes of chronic obstructive pulmonary disease (COPD). LncRNA colon cancer-associated transcript 1 (CCAT1) plays well-defined roles in the inflammatory progression. The study aims to figure out the effect and regulatory mechanism of CCAT1 in the cigarette smoke induced inflammation in COPD. The results showed that CCAT1 was highly expressed in lung tissues of smokers with COPD compared with never-smokers without COPD. In human bronchial epithelial (HBE) cells, cigarette smoke extract (CSE) treatment led to an increase in CCAT1 expression in a dose- and time- dependent manner. Functional experiments showed that knockdown of CCAT1 amelioratedCSE-inducedinflammation. Mechanistically, CCAT1 directly targeted miR-152-3p, and miR-152-3p overexpression reversed the pro-inflammatory effects of CCAT1 on HBE cells. Subsequently, miR-152-3p was found to regulate ERK signaling pathway. PD98059, an ERK specific inhibitor, reversed miR-152-3p knockdown mediated inflammation in HBE cells. In addition, CCAT1 acted as a sponge for miR-152-3p to positively regulate ERK signaling pathway. Overall, current findings suggest that CCAT1 promoted inflammation by activating ERK signal pathway via sponging miR-152-3p in CSE-treated HBE cells. These results may provide a novel therapeutic target for alleviating cigarette smoke mediated airway inflammation.