Cinnamaldehyde Inhibits Inflammation of Human Synoviocyte Cells Through Regulation of Jak/Stat Pathway and Ameliorates Collagen-Induced Arthritis in Rats

Network Pharmacology and Experimental Validation Reveal the Mechanisms of Sniffing Essential Oil of Acori Tatarinowii Rhizoma in Treating Olfactory Dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Acorus tatarinowii Rhizoma, a traditional Chinese medicine known for open the orifices and transform phlegm, is used in the treatment of brain disorders. The essential oil of Acorus tatarinowii Rhizoma (EOAT) has demonstrated neuroprotective properties clinically. However, research into its effect on Olfactory Dysfunction (OD) remains limited.

AIM OF THE STUDY

This study aimed to investigate the effects and mechanisms of sniffing EOAT on improving olfactory function in a 3-Methylindole (3-MI)-induced OD mouse model.

MATERIALS AND METHODS

The research involved intraperitoneal injection of 3-MI to induce OD in mice. The effects of EOAT treatment were assessed on olfactory function, olfactory bulb (OB) pathology, inflammatory factors, olfactory marker protein (OMP), microglial activation, and related pathway proteins and mRNA.

RESULTS

Based on the GC-MS analysis results of EOAT and network pharmacology studies, we predicted 18 targets associated with the treatment of OD. SLC6A3, MAOB, DRD1, and PTGS2 were identified as the core targets of EOAT against OD. Molecular docking and KEGG enrichment results indicated that EOAT may exert anti-inflammatory effects by acting on the core target PTGS2, with its anti-inflammatory mechanism possibly related to the PI3K/Akt signaling pathway. Subsequent animal experiments confirmed that inhalation of EOAT significantly increased the body weight of OD model mice, shortened the foraging time, enhanced the expression of OMP in OB , reduced damage to the OB cells, and improved olfactory function. Meanwhile, EOAT significantly alleviated the inflammatory response in OB of OD model mice, inhibited the activation of microglial cells, and suppressed the expression of PI3K/Akt signaling pathway proteins and mRNA.

CONCLUSION

EOAT inhalation could improve olfactory function in 3-MI-induced OD model. The underlying mechanism may be related to the modulation of the PI3K/Akt signaling pathway.

Biological fate, functional properties, and design strategies for oral delivery systems for cinnamaldehyde

Cinnamaldehyde (CA) is the main bioactive component extracted from the internal bark of cinnamon trees with many health benefits. In this paper, the bioavailability and biological activities of cinnamaldehyde, and the underlying molecular mechanism are reviewed and discussed, including antioxidant, cardioprotective, anti-inflammatory, anti-obesity, anticancer, and antibacterial properties. Common delivery systems that could improve the stability and bioavailability of CA are also summarized and evaluated, such as micelles, microcapsules, liposomes, nanoparticles, and nanoemulsions. This work provides a comprehensive understanding of the beneficial functions and delivery strategies of CA, which is useful for the future application of CA in the functional food industry.

Cinnamaldehyde targets SarA to enhance β-lactam antibiotic activity against methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a current global public health problem due to its increasing resistance to the most recent antibiotic therapies. One critical approach is to develop ways to revitalize existing antibiotics. Here, we show that the phytogenic compound cinnamaldehyde (CIN) and β-lactam antibiotic combinations can functionally synergize and resensitize clinical MRSA isolates to β-lactam therapy and inhibit MRSA biofilm formation. Mechanistic studies indicated that the CIN potentiation effect on β-lactams was primarily the result of inhibition of the mecA expression by targeting the staphylococcal accessory regulator sarA. CIN alone or in combination with β-lactams decreased sarA gene expression and increased SarA protein phosphorylation that impaired SarA binding to the mecA promoter element and downregulated virulence genes such as those encoding biofilm, α-hemolysin, and adhesin. Perturbation of SarA-mecA binding thus interfered with PBP2a biosynthesis and this decreased MRSA resistance to β-lactams. Furthermore, CIN fully restored the anti-MRSA activities of β-lactam antibiotics in vivo in murine models of bacteremia and biofilm infections. Together, our results indicated that CIN acts as a β-lactam adjuvant and can be applied as an alternative therapy to combat multidrug-resistant MRSA infections.

An in vitro study elucidating the synergistic effects of aqueous cinnamon extract and an anti-TNF-α biotherapeutic: implications for a complementary and alternative therapy for non-responders

BACKGROUND

Tumor necrosis factor-alpha (TNF-α) is a critical pro-inflammatory cytokine, and its abnormal production is associated with several immune mediated inflammatory diseases (IMID). Biological anti-TNF-α therapy includes treatment with monoclonal antibodies such as infliximab which have proven successful and are well-tolerated in most patients. Unfortunately, some patients may not respond to therapy (primary non-responders) or may lose sensitivity to the biological agent over time (early and late secondary non-responders). Natural products can reduce inflammation and act synergistically with small molecules or biologics, although evidence remains limited. This study aimed to investigate whether complementary and alternative medicine (CAM) could play a role in infliximab non-responders. Reportedly, cinnamon can help manage chronic inflammatory conditions owing to its anti-inflammatory properties.

METHODS

We studied the synergistic effects of cinnamon and infliximab in vitro using a two-step approach. First, we investigated whether cinnamon and infliximab act synergistically. Second, we selected conditions that supported statistically significant synergy with infliximab and studied the mRNA expression of several genes involved in non-response to infliximab. We used aqueous cinnamon extract (aCE) from Cinnamomum cassia, Cinnamomum zeylanicum, and Cinnamomum loureiroi and bioactive trans-cinnamaldehyde (TCA), cinnamic acid (CA), and eugenol to study the synergy between infliximab and aCE/bioactive compounds using bioassays in fibroblast (L929) and monocytic (U937) cell lines, followed by qPCR for molecular-level insights. TCA, C. cassia aCE, and C. zeylanicum aCE demonstrated a dose-dependent synergistic effect with infliximab. Moreover, we saw differential gene expression for adhesion molecules, apoptotic factors, signaling molecules, and matrix remodelers in presence and absence of aCE/bioactives.

RESULTS

CAM supplementation was most effective with C. cassia aCE, where a synergistic effect was observed for all the tested genes specifically for MMP-1, BcL-xL, Bax and JAK2, followed by TCA, which affected most of the tested genes except TLR-2, MMP1, MMP3, TIMP-1, and BAX, and C. zeylanicum aCE, which did not affect ICAM-1, VCAM-1, TLR-2, TLR-4, MMP1, MMP3, TIMP-1, and STAT3.

CONCLUSION

In conclusion, cinnamon acted synergistically with infliximab to mitigate inflammation when used as an extract. Purified bioactive TCA also showed synergistic activity. Thus, aCE, or cinnamon bioactive may be used as a CAM to improve patients' quality of life.

Bioactive Compounds from Plant Origin as Natural Antimicrobial Agents for the Treatment of Wound Infections

The rising prevalence of drug-resistant bacteria underscores the need to search for innovative and nature-based solutions. One of the approaches may be the use of plants that constitute a rich source of miscellaneous compounds with a wide range of biological properties. This review explores the antimicrobial activity of seven bioactives and their possible molecular mechanisms of action. Special attention was focused on the antibacterial properties of berberine, catechin, chelerythrine, cinnamaldehyde, ellagic acid, proanthocyanidin, and sanguinarine against Staphylococcus aureus, Enterococcus spp., Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Serratia marcescens and Pseudomonas aeruginosa. The growing interest in novel therapeutic strategies based on new plant-derived formulations was confirmed by the growing number of articles. Natural products are one of the most promising and intensively examined agents to combat the consequences of the overuse and misuse of classical antibiotics.

Molecular mechanism of the anti-inflammatory effects of plant essential oils: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Plant essential oils (PEOs) extracted from aromatic compounds of the plant contain complex mixtures of volatile and lipophilic bioactive compounds. In ancient Egypt, Arabia, Greece, and China, PEOs were traditional used in aromatherapy for various health disorders, including pain and inflammation.

AIM OF THE STUDY

In this review, we provide an overview of the anti-inflammatory effects of PEOs and the underlying mechanisms associated with anti-inflammatory effects using in vitro and in vivo models. Further, clinical trials associated with PEOs were explored.

MATERIALS AND METHODS

The literature search was performed using various web-based tools and databases like Google Scholar, Web of Science, PubMed, CNKI and SCOPUS. The keywords used for conducting the literature review were general terms like "essential oils" followed by (AND) the subject of interest like "in vitro and/or in vivo anti-inflammatory models," "inflammatory response," "inflammatory indicators," "pro-inflammatory cytokines," "signaling pathway," "anti-inflammatory mechanism," "toxicology and side effects" and "clinical trials." The articles selected were published between 2017 and 2022. The articles prior to 2017 were only considered if they were associated with molecular mechanisms or signaling pathways involved in the inflammatory responses.

RESULTS

In vitro and in vivo inflammation models have been used to study the anti-inflammatory effects of 48 PEOs. Studies have reported that PEOs targets and inhibit multiple dysregulated signaling pathways associated with inflammation, including Toll-like receptors, nuclear transcription factor-κ B, mitogen-activated protein kinases, Nod-like receptor family pyrin domain containing 3, and auxiliary pathways like the nuclear factor erythroid 2-related factor 2/antioxidant response element and Janus kinase/signal transducers and activators of transcription) signaling pathways.

CONCLUSION

PEOs extracted from different plant materials had varied qualitative and quantitative compositions of biologically active compounds. Different anti-inflammatory potentials and different molecular signal transduction have been attributed to PEOs-derived bioactive compounds with different chemical structures. The data on therapeutic efficacy and the long-term side effects of PEOs as an anti-inflammatory drug are still unknown due to the lack of clinical trials on PEOs. There is still insufficient evidence to draw conclusions on anti-inflammatory properties of PEOs without promising outcomes from clinical trials.

Cinnamon: an aromatic condiment applicable to chronic kidney disease

Cinnamon, a member of the Lauraceae family, has been widely used as a spice and traditional herbal medicine for centuries and has shown beneficial effects in cardiovascular disease, obesity, and diabetes. However, its effectiveness as a therapeutic intervention for chronic kidney disease (CKD) remains unproven. The bioactive compounds within cinnamon, such as cinnamaldehyde, cinnamic acid, and cinnamate, can mitigate oxidative stress, inflammation, hyperglycemia, gut dysbiosis, and dyslipidemia, which are common complications in patients with CKD. In this narrative review, we assess the mechanisms by which cinnamon may alleviate complications observed in CKD and the possible role of this spice as an additional nutritional strategy for this patient group.

Combination of Cinnamaldehyde with Carvacrol or Thymol Improves the Mechanical Properties of Tibia in Post-Peak Laying Hens

Roles of plant-derived cinnamaldehyde, carvacrol, and thymol in the gut and bone health of laying hens was evaluated in the present study. After acclimation for 2 weeks, a total 384 of 52-week-old laying hens were allocated into three groups for 6 weeks: (1) basal diet group (Ctrl), (2) combination of cinnamaldehyde with carvacrol group (CAR+CIN), and (3) blend of cinnamaldehyde with thymol (THY+CIN). The dietary essential oil level was 100 mg/kg. Each treatment group had eight replicate pens (16 birds/pen). The stiffness and ultimate load of the tibiae from both the CAR+CIN and THY+CIN groups were higher than that of the Ctrl group (p < 0.05), along with comparable tibia ash, calcium, and phosphorus content among groups. At the same time, the manipulation of essential oils upregulated the transcription abundances of intestinal barrier proteins to varying degrees, whereas the experimental treatment failed to affect the composition in phyla of cecal microbiota. When compared to the Ctrl group, birds fed the CAR+CIN and THY+CIN diet displayed decreased bone resorption markers, reduced interleukin-1 concentrations, and increased transforming growth factor beta levels in serum. These findings suggest that cinnamaldehyde with carvacrol or thymol in feed of hens could enhance intestinal barrier and improve the mechanical properties of tibiae through structural modelling but not increase the mineral density, which might be involved in suppressing inflammation-mediated bone resorption.

Clinical evidence construction of East Asian herbal medicine for inflammatory pain in rheumatoid arthritis based on integrative data mining approach

BACKGROUND

Rheumatoid arthritis (RA) is a chronic inflammatory disease that leads to a significant social burden. East Asian herbal medicine (EAHM) has long been used to treat RA. Therefore, a systematic study of how EAHM treatments can be developed into new drugs using specific materials is needed.

METHODS

Eleven databases containing literature in English, Korean, Chinese, and Japanese were searched for randomized controlled trials comparing EAHM with conventional medicine (CM). A meta-analysis was performed on the variable data to assess their effects on inflammatory pain. Subsequently, we searched for core materials and combinations of core material-based data mining methods.

RESULTS

A total of 186 trials involving 19,716 patients with RA met the inclusion criteria. According to the meta-analysis, EAHM had a significantly superior effect on continuous pain intensity, tender joint count, and response rate. Patients treated with EAHM had a significantly reduced incidence of adverse events compared with those treated with CM. Based on additional analysis of the EAHM formula data included in this meta-analysis, 21 core materials and five core herbal combinations were identified.

CONCLUSION

EAHM remedies for RA have the adequate potential for use as candidate materials for treating inflammatory pain in RA. The candidate core herbs evaluated in this study act on multiple pathways and are expected to provide pain relief, sustained inflammation suppression, immune regulation, and prevention of joint destruction. It seems worthwhile to conduct follow-up research on drug development using the core materials derived from this review.

Mechanism of tonifying-kidney Chinese herbal medicine in the treatment of chronic heart failure

According to traditional Chinese medicine (TCM), chronic heart failure has the basic pathological characteristics of “heart-kidney yang deficiency.” Chronic heart failure with heart- and kidney-Yang deficiency has good overlap with New York Heart Association (NYHA) classes III and IV. Traditional Chinese medicine classical prescriptions for the treatment of chronic heart failure often take “warming and tonifying kidney-Yang” as the core, supplemented by herbal compositions with functions of “promoting blood circulation and dispersing blood stasis.” Nowadays, there are still many classical and folk prescriptions for chronic heart failure treatment, such as Zhenwu decoction, Bushen Huoxue decoction, Shenfu decoction, Sini decoction, as well as Qili Qiangxin capsule. This review focuses on classical formulations and their active constituents that play a key role in preventing chronic heart failure by suppressing inflammation and modulating immune and neurohumoral factors. In addition, given that mitochondrial metabolic reprogramming has intimate relation with inflammation, cardiac hypertrophy, and fibrosis, the regulatory role of classical prescriptions and their active components in metabolic reprogramming, including glycolysis and lipid β-oxidation, is also presented. Although the exact mechanism is unknown, the classical TCM prescriptions still have good clinical effects in treating chronic heart failure. This review will provide a modern pharmacological explanation for its mechanism and offer evidence for clinical medication by combining TCM syndrome differentiation with chronic heart failure clinical stages.

pH-responsive cinnamaldehyde-TiO2 nanotube coating: fabrication and functions in a simulated diabetes condition

Current evidence has suggested that diabetes increases the risk of implanting failure, and therefore, appropriate surface modification of dental implants in patients with diabetes is crucial. TiO₂ nanotube (TNT) has an osteogenic nanotopography, and its osteogenic properties can be further improved by loading appropriate drugs. Cinnamaldehyde (CIN) has been proven to have osteogenic, anti-inflammatory, and anti-bacterial effects. We fabricated a pH-responsive cinnamaldehyde-TiO₂ nanotube coating (TNT-CIN) and hypothesized that this coating will exert osteogenic, anti-inflammatory, and anti-bacterial functions in a simulated diabetes condition. TNT-CIN was constructed by anodic oxidation, hydroxylation, silylation, and Schiff base reaction to bind CIN, and its surface characteristics were determined. Conditions of diabetes and diabetes with a concurrent infection were simulated using 22-mM glucose without and with 1-μg/mL lipopolysaccharide, respectively. The viability and osteogenic differentiation of bone marrow mesenchymal stem cells, polarization and secretion of macrophages, and resistance to Porphyromonas gingivalis and Streptococcus mutans were evaluated. CIN was bound to the TNT surface successfully and released better in low pH condition. TNT-CIN showed better osteogenic and anti-inflammatory effects and superior bacterial resistance than TNT in a simulated diabetes condition. These findings indicated that TNT-CIN is a promising, multifunctional surface coating for patients with diabetes needing dental implants. Graphical abstract.

Natural medicines of targeted rheumatoid arthritis and its action mechanism

Rheumatoid arthritis (RA) is an autoimmune disease involving joints, with clinical manifestations of joint inflammation, bone damage and cartilage destruction, joint dysfunction and deformity, and extra-articular organ damage. As an important source of new drug molecules, natural medicines have many advantages, such as a wide range of biological effects and small toxic and side effects. They have become a hot spot for the vast number of researchers to study various diseases and develop therapeutic drugs. In recent years, the research of natural medicines in the treatment of RA has made remarkable achievements. These natural medicines mainly include flavonoids, polyphenols, alkaloids, glycosides and terpenes. Among them, resveratrol, icariin, epigallocatechin-3-gallate, ginsenoside, sinomenine, paeoniflorin, triptolide and paeoniflorin are star natural medicines for the treatment of RA. Its mechanism of treating RA mainly involves these aspects: anti-inflammation, anti-oxidation, immune regulation, pro-apoptosis, inhibition of angiogenesis, inhibition of osteoclastogenesis, inhibition of fibroblast-like synovial cell proliferation, migration and invasion. This review summarizes natural medicines with potential therapeutic effects on RA and briefly discusses their mechanisms of action against RA.

Targeting inflammation and redox perturbations by lisinopril mitigates Freund's adjuvant-induced arthritis in rats: role of JAK-2/STAT-3/RANKL axis, MMPs, and VEGF

BACKGROUND

Cardiovascular disorders are major complications of rheumatoid arthritis (RA). Hence, finding effective agents that can target RA progression and its cardiovascular consequences is demanding. The present work aimed to explore the potential of lisinopril, an angiotensin-converting enzyme inhibitor, to mitigate adjuvant's-induced arthritis with emphasis on the pro-inflammatory signals, articular degradation cues, and angiogenesis alongside JAK-2/STAT-3 and Nrf2/HO-1 pathways.

METHODS

Lisinopril (10 mg/kg/day) was administered by oral gavage for 3 weeks and the target signals were examined by biochemical assays, ELISA, histopathology, immunoblotting, and immunohistochemistry.

RESULTS

Lisinopril attenuated the progression of arthritis as proven by lowering paw edema, arthritic index, and gait scores alongside diminishing the immune-cell infiltration/aberrant histopathology in the dorsal pouch lining. These favorable actions were associated with curtailing the production of inflammatory cytokines (TNF-α, IL-6, IL-1β, and IL-17) and the pro-inflammatory angiotensin II alongside upregulating the anti-inflammatory angiotensin-(1-7) in the hind paw of arthritic rats. At the molecular level, lisinopril inhibited the upstream JAK-2/STAT-3 pathway by downregulating the protein expression of p-JAK-2/total JAK-2 and p-STAT-3/total STAT-3 ratio and the nuclear levels of NF-κBp65. Meanwhile, lisinopril curbed the downstream cartilage degradation signals matrix metalloproteinases (MMP-3 and MMP-9) and the bone erosion cue RANKL. Equally important, the protein expression of the angiogenesis signal VEGF was downregulated in the hind paw/dorsal lining. With respect to oxidative stress, lisinopril suppressed the paw lipid peroxides and boosted GSH and Nrf-2/HO-1 pathway.

CONCLUSION

Lisinopril attenuated adjuvant-induced arthritis via inhibition of inflammation, articular degradation cues, and angiogenesis.

The Potential Complementary Role of Using Chinese Herbal Medicine with Western Medicine in Treating COVID-19 Patients: Pharmacology Network Analysis

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic in 2019—coronavirus disease (COVID-19). More and more Western medicine (WM) and Chinese herbal medicine (CHM) treatments have been used to treat COVID-19 patients, especially among Asian populations. However, the interactions between WM and CHM have not been studied. This study aims at using the network pharmacology approach to explore the potential complementary effects among commonly used CHM and WM in a clinical setting from a biomolecular perspective. Three well-published and widely used CHM formulas (National Research Institute of Chinese Medicine 101 (NRICM101), Qing-Fei-Pai-Du-Tang (QFPDT), Hua-Shi-Bai-Du-Formula (HSBDF)) and six categories of WM (Dexamethasone, Janus kinase inhibitors (JAKi), Anti-Interleukin-6 (Anti-IL6), anticoagulants, non-vitamin K antagonist oral anticoagulants (NOAC), and Aspirin) were included in the network pharmacology analysis. The target proteins on which these CHM and WM had direct effects were acquired from the STITCH database, and the potential molecular pathways were found in the REACTOME database. The COVID-19-related target proteins were obtained from the TTD database. For the three CHM formulas, QFPDT covered the most proteins (714), and 27 of them were COVID-19-related, while HSBDF and NRICM101 covered 624 (24 COVID-19-related) and 568 (25 COVID-19-related) proteins, respectively. On the other hand, WM covered COVID-19-related proteins more precisely and seemed different from CHM. The network pharmacology showed CHM formulas affected several inflammation-related proteins for COVID-19, including IL-10, TNF-α, IL-6, TLR3, and IL-8, in which Dexamethasone and Aspirin covered only IL-10 and TNF-α. JAK and IL-6 receptors were only inhibited by WM. The molecular pathways covered by CHM and WM also seemed mutually exclusive. WM had advantages in cytokine signaling, while CHM had an add-on effect on innate and adaptive immunity, including neutrophil regulation. WM and CHM could be used together to strengthen the anti-inflammation effects for COVID-19 from different pathways, and the combination of WM and CHM may achieve more promising results. These findings warrant further clinical studies about CHM and WM use for COVID-19 and other diseases.

Novel anti-arthritic mechanisms of trans-cinnamaldehyde against complete Freund's adjuvant-induced arthritis in mice: involvement of NF-кB/TNF-α and IL-6/IL-23/ IL-17 pathways in the immuno-inflammatory responses

Trans-cinnamaldehyde (TCA), a natural cinnamaldehyde derivative of cinnamon oil, is known for anti-inflammatory, anti-bacterial, anti-fungal, anti-diabetic, and anti-cancer activities. However, no study has examined the protective mechanisms of TCA on complete Freund's adjuvant (CFA)-induced arthritis. Chronic arthritis was induced in mice by triple dose injection of 0.1 ml CFA in the first two days, then a treatment with TCA (100 mg/kg, i.p.) and the anti-arthritic drug; methotrexate (MTX, 0.75 mg/kg, i.p., 3 times/week) started from day 10 after CFA and continued till day 35.TCA ameliorated the CFA-induced arthritis features, indicated by the decrease in serum rheumatoid factor, paw swelling, arthritis index and the arthritis changes in limb histology. Additionally, TCA treatment showed anti-inflammatory actions through downregulation of TNF-α, NF-κB and COX-2 expressions and marked reduction in IL-1β, IL-6, IL-23 and IL-17 levels in inflamed paw tissues.Consequently, TCA can decrease arthritis progression and inhibit the immune/inflammatory responses initiated by TNF-α/IL-1β/IL-6/IL-23/IL-17 signals, via NF-κB modulation, almost to the same extent accomplished by MTX. Therefore, TCA could be a promising anti-arthritic drug.

The Inflammatory Response in Human Keratinocytes Exposed to Cinnamaldehyde Is Regulated by Nrf2

Keratinocytes (KC) play a crucial role in epidermal barrier function, notably through their metabolic activity and the detection of danger signals. Chemical sensitizers are known to activate the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2), leading to cellular detoxification and suppressed proinflammatory cytokines such as IL-1β, a key cytokine in skin allergy. We investigated the role of Nrf2 in the control of the proinflammatory response in human KC following treatment with Cinnamaldehyde (CinA), a well-known skin sensitizer. We used the well-described human KC cell line KERTr exposed to CinA. Our results showed that 250 μM of CinA did not induce any Nrf2 accumulation but increased the expression of proinflammatory cytokines. In contrast, 100 μM of CinA induced a rapid accumulation of Nrf2, inhibited IL-1β transcription, and downregulated the zymosan-induced proinflammatory response. Moreover, Nrf2 knockdown KERTr cells (KERTr ko) showed an increase in proinflammatory cytokines. Since the inhibition of Nrf2 has been shown to alter cellular metabolism, we performed metabolomic and seahorse analyses. The results showed a decrease in mitochondrial metabolism following KERTr ko exposure to CinA 100 µM. In conclusion, the fate of Nrf2 controls proinflammatory cytokine production in KCs that could be linked to its capacity to preserve mitochondrial metabolism upon chemical sensitizer exposure.

Cinnamaldehyde protect against ligature-induced periodontitis through inhibitions of microbial accumulation and inflammatory responses of host immune cells

Cinnamaldehyde (CA), the main active ingredient of cinnamon, is proved to be a potential candidate of controlling inflammation, but few evidences are demonstrated on its role in periodontitis. The aim...

Research Progress of Therapeutic Enzymes and Their Derivatives: Based on Herbal Medicinal Products in Rheumatoid Arthritis

Rheumatoid arthritis (RA) acts as one of the most common, agnogenic and chronic inflammatory-autoimmune disorder which is characterized by persistent synovitis, cartilage destruction, and joint deformities, leads to a wide range of disabilities, and increased mortality, thus imposing enormous burdens. Several drugs with anti-inflammatory and immunomodulatory properties such as celecoxib, diclofenac and methotrexate are being selected as conventional drugs in the allopathic system of medicine for the treatment of RA in clinic. However, there are some serious side effects more or less when using these drugs because of their short poor bioavailability and biological half-life for a long time. These shortcomings greatly promote the exploration and application of new low- or no-toxicity drugs for treating the RA. Meanwhile, a growing number of studies demonstrate that several herbs present certain anti-inflammatory and anti-arthritic activities through different enzymes and their derivatives, which indicate that they are promising therapeutic strategies when targeting these mediators based on herbal medicinal products in RA research. This review article summarizes the roles of the main enzymes and their derivatives during the pathogenesis of RA, and clearly clarifies the explicit and potential targeted actions of herbal medicinal products that have anti-RA activity. Our review provides timely and critical reference for the scientific rationale use of herbal medicinal products, with the increasing basic research and clinical application of herbal medicinal products by patients with RA.

Cinnamaldehyde and hesperetin attenuate TNBS-induced ulcerative colitis in rats through modulation of the JAk2/STAT3/SOCS3 pathway

Ulcerative colitis is an autoimmune inflammatory disorder with a negative impact on the life quality of patients. Cinnamaldehyde and hesperetin were chosen due to their antioxidants and anti-inflammatory effects. This study explored the protective effects of cinnamaldehyde (40 and 90 mg/kg, po) and hesperetin (50 and 100 mg/kg, po) on 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced ulcerative colitis in rats. Cinnamaldehyde and hesperetin significantly improved macroscopic and histopathological examinations with a significant reduction in myeloperoxidase and intracellular adhesion molecule-1 expression. They significantly reduced colon oxidative stress by a significant elevation in both reduced glutathione content and superoxide dismutase activity with a significant reduction of NO content. Furthermore, cinnamaldehyde and hesperetin alleviated the inflammatory injury by a significant reduction in interleukin-6 along with suppression of nuclear factor-κB, receptor for advanced glycation end products, and tumor necrosis factor-α expression. Moreover, cinnamaldehyde and hesperetin significantly decreased p-JAK2 and p-STAT3 while significantly increased suppressors of cytokine signaling 3 (SOCS3) protein expression. In conclusion, cinnamaldehyde and hesperetin counteracted TNBS-induced ulcerative colitis through antioxidant, anti-inflammatory properties as well as modulation of the JAk2/STAT3/SOCS3 pathway.

Suppression of lncRNA MALAT1 reduces pro-inflammatory cytokines production by regulating miR-150-5p/ZBTB4 axis through JAK/STAT signal pathway in systemic juvenile idiopathic arthritis

Systemic juvenile idiopathic arthritis (sJIA) is a common chronic disease occurring in children. Increasing studies have demonstrated that long noncoding RNAs (lncRNAs) play important roles in the pathogenesis of diverse human diseases. This study aimed to explore the role of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and its mechanism in sJIA. We found that the expression of MALAT1, the plasma level of pro-inflammatory cytokines (IL-6, IL-17, IL-1β, and TNF-α) as well as MMP-8 and MMP-9 production were significantly elevated in sJIA patients. Moreover, we observed that the production of these cytokines in peripheral blood mononuclear cells (PBMCs) from sJIA patients were reduced after MALAT1 knockdown. Furthermore, bioinformatics analysis predicted that MALAT1 might bind to miR-150-5p and ZBTB4 was a downstream target gene of miR-150-5p. Besides, rescue assays revealed that MALAT1 knockdown-mediated suppressive effects on cytokine production could be reversed by ZBTB4 overexpression. In addition, MALAT1 activated the JAK/STAT signaling by upregulating ZBTB4 expression. In summary, our findings demonstrated that MALAT1 promoted pro-inflammatory cytokine and MMP production by targeting the miR-150-5p/ZBTB4 axis through JAK/STAT signaling pathway in sJIA, suggesting that MALAT1 may have a potential diagnostic biomarker for the pathogenesis and therapy of sJIA.

Can cinnamon spice down autoimmune diseases?

Autoimmune diseases are one of the dreadful group of human diseases that have always been of keen interest to researchers. Due to complex and broad-spectrum nature, scientists are not yet able to pinpoint the pathogenesis of and delineate effective therapy against this group of diseases. However, it is becoming clear that a decrease in number and function of T regulatory cells (Treg), an increase in autoreactive Th1/Th17 cells and associated immunomodulation and inflammation participate in the pathogenesis of many autoimmune diseases. Cinnamon (Cinnamonum verum or Cinnamonum cassia) is a widely used natural spice and flavoring ingredient and its metabolite sodium benzoate (NaB) is a food-additive and FDA-approved drug against nonketotic hyperglycinemia (NKH) and urea cycle disorders (UCD). Recent studies indicate that cinnamon either in powder or extract form and NaB are capable of modulating different autoimmune pathways as well as protecting animals from different autoimmune disorders. Here, we have made an honest attempt to delineate such pieces of evidence with available anti-autoimmune mechanisms and analyze whether cinnamon supplements could be used to control the fury of autoimmune disorders.

Mechanisms of Herb-Drug Interactions Involving Cinnamon and CYP2A6: Focus on Time-Dependent Inhibition by Cinnamaldehyde and 2-Methoxycinnamaldehyde

Information is scarce regarding pharmacokinetic-based herb-drug interactions (HDI) with trans-cinnamaldehyde (CA) and 2-methoxycinnamaldehyde (MCA), components of cinnamon. Given the presence of cinnamon in food and herbal treatments for various diseases, HDIs involving the CYP2A6 substrates nicotine and letrozole with MCA (KS = 1.58 µM; Hill slope = 1.16) and CA were investigated. The time-dependent inhibition (TDI) by MCA and CA of CYP2A6-mediated nicotine metabolism is a complex process involving multiple mechanisms. Molecular dynamic simulations showed that CYP2A6's active site accommodates two dynamic ligands. The preferred binding orientations for MCA and CA were consistent with the observed metabolism: epoxidation, O-demethylation, and aromatic hydroxylation of MCA and cinnamic acid formation from CA. The percent remaining activity plots for TDI by MCA and CA were curved, and they were analyzed with a numerical method using models of varying complexity. The best-fit models support multiple inactivator binding, inhibitor depletion, and partial inactivation. Deconvoluted mass spectra indicated that MCA and CA modified CYP2A6 apoprotein with mass additions of 156.79 (142.54-171.04) and 132.67 (123.37-141.98), respectively, and it was unaffected by glutathione. Heme degradation was observed in the presence of MCA (48.5% ± 13.4% loss; detected by liquid chromatography-tandem mass spectrometry). In the absence of clinical data, HDI predictions were made for nicotine and letrozole using inhibition parameters from the best-fit TDI models and parameters scaled from rats. Predicted area under the concentration-time curve fold changes were 4.29 (CA-nicotine), 4.92 (CA-letrozole), 4.35 (MCA-nicotine), and 5.00 (MCA-letrozole). These findings suggest that extensive exposure to cinnamon (corresponding to ≈ 275 mg CA) would lead to noteworthy interactions. SIGNIFICANCE STATEMENT: Human exposure to cinnamon is common because of its presence in food and cinnamon-based herbal treatments. Little is known about the risk for cinnamaldehyde and methoxycinnamaldehyde, two components of cinnamon, to interact with drugs that are eliminated by CYP2A6-mediated metabolism. The interactions with CYP2A6 are complex, involving multiple-ligand binding, time-dependent inhibition of nicotine metabolism, heme degradation, and apoprotein modification. An herb-drug interaction prediction suggests that extensive exposure to cinnamon would lead to noteworthy interactions with nicotine.

Essential Oils and Bioactive Components against Arthritis: A Novel Perspective on Their Therapeutic Potential

Essential oils (EOs) are known to possess a number of beneficial properties. Their antimicrobial, anti-inflammatory, antioxidant, antidiabetic, and cancer-preventing activities have been extensively reported. Due to their wide use as food preservers and additives, as well as their use in agriculture, perfumes, and make-up products, these complex mixtures of volatile compounds have gained importance from a commercial point of view, not only in the pharmaceutical industry, but also in agronomic, food, cosmetic, and perfume industries. An analysis of the recent scientific literature allowed us to highlight the presence of an increasing number of studies on the potential antiarthritic properties of EOs and their main constituents, which seems to suggest a new interesting potential therapeutic application. The aim of this review is to examine the current knowledge on the beneficial effects of essential oils in the treatment of arthritic diseases, providing an overview of the reports on the in vivo and in vitro effects of EOs. Furthermore, this review critically examines the recent findings on the potential roles of the main components of EOs in the exerted beneficial effects. Obtained negative results are also reported.

Aliskiren, tadalafil, and cinnamaldehyde alleviate joint destruction biomarkers; MMP-3 and RANKL; in complete Freund's adjuvant arthritis model: Downregulation of IL-6/JAK2/STAT3 signaling pathway

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease, which is accompanied by progressive joint damage and disability. The intolerability of conventional antirheumatic drugs by some patients necessitates the search for effective antirheumatic agents having better tolerability. In the current work, we aimed to investigate the efficacy of cinnamaldehyde, tadalafil, and aliskiren as potential antirheumatic candidates and to explore their modulatory effects on joint destruction, inflammatory response, and intracellular signaling. Arthritis was induced in female Wistar rats by complete Freund's adjuvant (CFA) 0.4 ml s.c. on days 1, 4, and 7. Treated groups received their respective drugs, starting from day 13, daily for 3 weeks. Methotrexate and prednisolone were the standard antirheumatic drugs, while cinnamaldehyde, tadalafil, and aliskiren were the test agents. Treatment with cinnamaldehyde, tadalafil, or aliskiren reduced serum levels of rheumatoid factor, and pro-inflammatory cytokines; tumor necrosis factor-alpha and interleukin-6 (IL-6), along with elevated level of IL-10 which is an anti-inflammatory cytokine. Besides, cartilage and bone destruction biomarkers; matrix metalloproteinase-3 (MMP-3) and receptor activator of nuclear factor-kappa B ligand (RANKL); were significantly reduced after treatment with the test agents, which was further confirmed by histopathological investigation. The elevated protein expressions of phosphorylated-Janus kinase 2 (p-JAK2), phosphorylated-signal transducer and activator of transcription 3 (p-STAT3), and inducible nitric oxide synthase (iNOS) in articular tissue were markedly attenuated after treatment with cinnamaldehyde, tadalafil, or aliskiren, while that of endothelial nitric oxide synthase (eNOS) was greatly enhanced. In addition, oxidative stress and inflammatory markers such as malondialdehyde, nitric oxide, and myeloperoxidase were reduced in joint tissue after treatment with the test agents, while glutathione content was elevated. Furthermore, the renin inhibitor aliskiren produced effects close to those of the normal and methotrexate, the gold standard antirheumatic drug, in most of the measured parameters.

Collectively, these findings led to the assumption that the downregulation of IL-6/JAK2/STAT3 signaling by cinnamaldehyde, tadalafil, and aliskiren could alleviate joint destruction by MMP-3 and RANKL, reduce iNOS, and enhance eNOS expressions. Moreover, aliskiren could be a promising therapeutic agent for RA, because of its ability to normalize most of the measured parameters after CFA-induced arthritis.

Tocilizumab-Conjugated Polymer Nanoparticles for NIR-II Photoacoustic-Imaging-Guided Therapy of Rheumatoid Arthritis

The progressive debilitating nature of rheumatoid arthritis (RA) combined with its unknown etiology and initial similarity to other inflammatory diseases makes early diagnosis a significant challenge. Early recognition and treatment of RA is essential for achieving effective therapeutic outcome. NIR-II photoacoustic (PA) molecular imaging (PMI) is emerging as a promising new strategy for effective diagnosis and treatment guidance of RA, owing to its high sensitivity and specificity at large penetration depth. Herein, an antirheumatic targeted drug tocilizumab (TCZ) is conjugated to polymer nanoparticles (PNPs) to develop the first NIR-II theranostic nanoplatform, named TCZ-PNPs, for PA-imaging-guided therapy of RA. The TCZ-PNPs are demonstrated to have strong NIR-II extinction coefficient, high photostability and excellent biocompatibility. NIR-II PMI results reveal the excellent targeting abilities of TCZ-PNPs for the effective noninvasive diagnosis of RA joint tissue with a high signal-to noise ratio (SNR) of 35.8 dB in 3D PA tomography images. Remarkably, one-month treatment and PA monitoring using TCZ-PNPs shows RA is significantly suppressed. In addition, the therapeutic evaluation of RA mice by NIR-II PMI is shown to be consistent with clinical micro-CT and histological analysis. The TCZ-PNPs-assisted NIR-II PMI provides a new strategy for RA theranostics, therapeutic monitoring and the beyond.

The modulatory effects of cinnamaldehyde on uric acid level and IL-6/JAK1/STAT3 signaling as a promising therapeutic strategy against benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a widespread disorder in elderly men. Cinnamaldehyde, which is a major constituent in the essential oil of cinnamon, has been previously reported to reduce xanthine oxidase activity, in addition to its anti-inflammatory, anti-oxidant, and anti-proliferative activities. Our study was designed to investigate the potential modulatory effects of cinnamaldehyde on testosterone model of BPH in rats through reduction of uric acid level, and suppression of IL-6/JAK1/STAT3 signaling pathway. Cinnamaldehyde (40 and 75 mg/kg) was orally administered to male Wistar rats for 3 weeks, and concurrently with testosterone (3 mg/kg, s.c.) from the second week. Cinnamaldehyde ameliorated the elevation in prostatic weight and index compared to rats treated with testosterone only, that was also confirmed by alleviation of histopathological changes in prostate architecture. The protective mechanisms of cinnamaldehyde were elucidated through inhibition of xanthine oxidase activity and reduced uric acid level. That was accompanied by reduction of the pro-inflammatory cytokines; interleukin-6 (IL-6), IL-1β, tumor necrosis factor-alpha (TNF-α), and the nuclear translocation of the transcription factor NF-κB p65, that could be attributed also to the enhanced anti-oxidant defense by cinnamaldehyde. The protein expression of JAK1, which is IL-6 receptor linked protein, was reduced with subsequently reduced activation of STAT3 protein. That eventually suppressed the formation of the proliferation protein cyclin D1, while elevated Bax/Bcl2 ratio. It can be concluded that reducing uric acid level through xanthine oxidase inhibition and suppression of the inflammatory signaling cascade; IL-6/JAK1/STAT3; by cinnamaldehyde could be a novel and promising therapeutic approach against BPH.

Anti-inflammatory effects of Jingshu Keli capsule and its components on human synoviocyte MH7A cells

BACKGROUND

Jingshu Keli (JSKL), a traditional Chinese medicine (TCM) formula consisting of multiple active compounds, has been officially approved by National Medical Products Administration (NMPA) for treatment of cervical radiculopathy. It relieves pain, according to TCM theory, by activating blood circulation to dissipate blood stasis. The pain mainly stems from neurogenic inflammation caused by mechanical compression of the cervical nerve root. In addition, inflammation mediators also cause the development of other joint diseases, such as osteoarthritis (OA). The purpose of this paper was to evaluate the anti-inflammatory effects of JSKL and identify the biologically active herbs and compounds in vitro.

METHODS

Enzyme-linked immunosorbent assay (Elisa) was used to determine the expression of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) and interleukin 8 (IL-8), in the culture medium of human MH7A cells stimulated by lipopolysaccharides (LPS).

RESULTS

JSKL and three single-herb capsules, Cinnamomum cassia Presl (C.C.), Angelica Sinensis (Oliv.) Diels (A.S.) and Carthamus tinctorius L. (C.T.), significantly inhibited the secretion of TNF-α. If one of these three herbal components was removed, suppressing effect of the single-herb-deleted JSKL on TNF-α was abolished. Cinnamaldehyde (CIN) from C.C. was the most potent ingredient that inhibited the expression of IL-6 and IL-8 in the culture medium of both LPS-stimulated MH7A cells and primary synovial cells.

CONCLUSIONS

JSKL was found to possess anti-inflammatory effect in vitro; C.C., A.S. and C.T. were the principal and essential herbal components responsible for such activity; CIN from C.C. is one the most potent single compound among indicator components of JSKL recorded in 2015 Chinese pharmacopoeia. This study provided scientific evidence for the clinical application of JSKL as an agent for targeted treatment of cervical radiculopathy. Furthermore, CIN has potential to be used for the treatment of some inflammation-related orthopedic diseases, such as rheumatic arthritis and osteoarthritis.