Evidence of anti-inflammatory activity of Schizandrin A in animal models of acute inflammation

Evaluation of hematoprotective, hepatoprotective, and anti-inflammatory potentials of chia seed (Salvia hispanica L.) extract in rats

This study was conducted to evaluate the effects of chia seed extract on CCl4-induced hepatotoxicity, hematological profile, and carrageenan-induced inflammation in rats. Water-ethanol-acetone extract of chia seeds at the doses of 200 and 400 mg/kg body weight/day were applied to evaluate the comparative protective roles. Hematological profile and serum biochemical parameters were measured to evaluate the hematoprotective, and hepatoprotective effects of chia seed extract. Paw thickness and motility level were assessed at 0, 1, 3, 5, and 7 h after sub-planter injection of carrageenan to evaluate the anti-inflammatory potential. Tissue histopathology was performed in both cases. Chia seed extract reduced the elevated level of serum AST and ALT significantly in a dose-dependent manner following intra-peritoneal injection of CCl4. Histopathological study of the liver tissue exhibited acute impairment of the hepatocytes and liver parenchyma following CCl4 exposure, which was markedly regenerated by the chia seed extract treatment. Protective effects of the extracts were also evidenced by the RBC count, Hb (%), PCV (%), ESR, and neutrophil count. Chia seed extract was found to inhibit the carrageenan-induced paw edema and increase motility level in a dose-oriented fashion. Histological examination of the paw tissue revealed severe inflammation characterized by massive infiltration of inflammatory cells in the carrageenan group, which was significantly reduced by chia seed extract treatment. The higher dose of chia seed extract showed significant increases in bodyweight gain and feed efficiency ratio but decrease in visceral fat deposition. These results suggest that chia seeds possess potentials for hematoprotective, hepatoprotective, and anti-inflammatory activities.

Schisandrin A Alleviates Spatial Learning and Memory Impairment in Diabetic Rats by Inhibiting Inflammatory Response and Through Modulation of the PI3K/AKT Pathway

Clinical and epidemiological research shows that people with diabetes mellitus frequently experience diabetic cognitive impairment. Schisandrin A (SchA), one of the lignans found in the dried fruit of Schisandra chinensis, has a variety of pharmacological effects on immune system control, apoptosis suppression, anti-oxidation and anti-inflammation. The goal of the current investigation was to clarify the probable neuro-protective effects of SchA against streptozotocin-induced diabetes deficiencies of the spatial learning and memory in rats. The outcomes show that SchA therapy effectively improved impaired glucose tolerance, fasting blood glucose level and serum insulin level in diabetic rats. Additionally, in the Morris water maze test, diabetic rats showed deficits in spatial learning and memory that were ameliorated by SchA treatment. Moreover, giving diabetic rats SchA reduced damage to the hippocampus structure and increased the production of synaptic proteins. Further research revealed that SchA therapy reduced diabetic-induced hippocampus neuron damage and the generation of Aβ, as demonstrated by the upregulated phosphorylation levels of insulin signaling pathway connected proteins and by the decreased expression levels of inflammatory-related factors. Collectively, these results suggested that SchA could improve diabetes-related impairments in spatial learning and memory, presumably by reducing inflammatory responses and regulating the insulin signaling system.

Schisandrin A ameliorates airway inflammation in model of asthma by attenuating Th2 response

Asthma is a persistent respiratory ailment that displays periodicity and is linked to the equilibrium of T cells. Several compounds obtained from Chinese herbal medicines display beneficial impacts on T cell regulation and the attenuation of inflammatory mediator synthesis. Schisandrin A, an active lignan derived from the Schisandra fruit, exhibits anti-inflammatory characteristics. In the present study, the network analysis conducted revealed that the nuclear factor-kappaB (NF-κB) signaling pathway is likely a prominent contributor to the anti-asthmatic effects of schisandrin A. In addition, it has been established that the inhibition of cyclooxygenase 2 (COX-2/PTGS2) is likely a significant factor in this process. The results of in vitro experiments have substantiated that schisandrin A can effectively lower the expression of COX-2 and inducible nitric oxide synthase (iNOS) in 16 HBE cells and RAW264.7 cells in a manner that is dependent on the dosage administered. It was able to effectively reduce the activation of the NF-κB signaling pathway while simultaneously improving the injury to the epithelial barrier function. Furthermore, an investigation utilizing immune infiltration as a metric revealed an inequity in Th1/Th2 cells and a surge in Th2 cytokines in asthma patients. In the OVA-induced asthma mice model, it was observed that schisandrin A treatment effectively suppressed inflammatory cell infiltration, reduced the Th2 cell ratio, inhibited mucus secretion, and prevented airway remodeling. To summarize, the administration of schisandrin A has been found to effectively alleviate the symptoms of asthma by impeding the production of inflammation, which includes reducing the Th2 cell ratio and improving the integrity of the epithelial barrier function. These findings offer valuable insights into the potential therapeutic applications of schisandrin A for the treatment of asthma.

Thymoquinone counteracts oxidative and inflammatory machinery in carrageenan-induced murine paw edema model

Thymoquinone (TQ) is an active constituent in Nigella sativa (black cumin) and is extensively reported for its distinguished antioxidant and anti-inflammatory bioactivities. Despite the local protective response of acute inflammation, it contributes to the development of various disease conditions such as cell death, organ damage, or carcinogenesis. Hence, in this study, the effects of orally administered TQ (50 mg/kg and 100 mg/kg) for 14 days against edema development, oxidative stress, and inflammation were investigated in paw edema induced by carrageenan in mice. Indomethacin (10 mg/kg) was used as a reference drug. The results revealed that TQ reduced the paw edema volume in a time-dependent manner, attenuated acetic acid-provoked writhing movements, and reduced xylene-triggered ear edema. Hematological findings revealed marked normalization of altered counts of WBCs, and platelets. Furthermore, paw tissue levels of malondialdehyde and nitric oxide showed marked decreases together with increases in nuclear factor erythroid 2-related factor 2, glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase after TQ administration. Additionally, TQ decreased pro-inflammatory mediators, such as interleukin-1 beta, tumor necrosis factor-alpha, interleukin-6, monocyte chemoattractant protein-1, C-reactive protein, myeloperoxidase, and nuclear factor kappa-B in the inflamed paw tissue. Moreover, appreciable decreases were recorded in cyclooxygenase-2 and its product prostaglandin E2 and the immune reaction of tumor necrosis factor-alpha in TQ-treated mice. Histopathological findings further validated the potential antiedematous, anti-inflammatory power of TQ in inflamed tissues. Conclusively, the results encourage the potent application of TQ to subside acute inflammatory events because of its striking antioxidant and anti-inflammatory properties in inflamed paw tissue.

Schizandrin A enhances killing effect of oxaliplatin on colorectal cancer cells

BACKGROUND

Schizandrin A (SchA) has anticancer and multidrug resistance-reversing effects in a variety of tumors, but its effect on oxaliplatin (L-OHP) in colorectal cancer cells is not clear.

AIM

To investigate whether SchA can enhance the killing effect of L-OHP on colorectal cancer cells, and to analyze the possible mechanism involved.

METHODS

Colorectal cancer cells were divided into control group, SchA treatment group, L-OHP treatment group, and SchA + L-OHP treatment group. Cell viability was detected by MTT assay. Cell apoptosis was detected by flow cytometry. The contents of reactive oxygen species (ROS) in cells was detected using a ROS probe. Mitochondrial membrane potential was evaluated by using the 1,1',3,3'-tetraethyl-5,5',6,6'-tetrachloroimidacarbocyanine iodide (JC-1) probe. Western blot was used to detect the expression of B-cell lymphoma 2 (Bcl-2), Bcl-2 associated X protein (Bax), cytochrome c (Cyt c), and cleaved cysteine proteinase-3 (caspase-3) in the cells.

RESULTS

Compared with the L-OHP treatment group, the viability of colorectal cancer cells in the SchA + L-OHP treatment group was significantly decreased, while apoptosis was significantly increased. SchA could enhance ROS accumulation, Bax and cleaved caspase-3 expression, and mitochondrial Cyt c release, and decrease Bcl-2 expression in colorectal cancer cells induced by L-OHP.

CONCLUSION

SchA enhances the killing effect of L-OHP on colorectal cancer cells, and the mechanism may be related to the enhancement of intracellular ROS accumulation and the expression of apoptosis-related proteins.

Alloferon-1 ameliorates acute inflammatory responses in λ-carrageenan-induced paw edema in mice

Alloferon-1 have been proposed as an effective peptide to enhance antitumoral immunity, antiviral defense and anti-inflammatory activity. This work aimed to assess anti-inflammatory effects of alloferon-1 against acute inflammation and histopathological deformations in λ-carrageenan-induced paw edema in mice. Systemic pretreatment with alloferon-1 (22.0 mg/kg) intraperitoneally injected mice showed a significant reduction in paw thickness and vascular permeability. Alloferon-1 prevented λ-carrageenan-evoked exudation and the neutrophil influx to the mouse pleura and the neutrophil migration into carrageenan-stimulated mouse air pouches based on the histopathological changes in the paw tissues. Administration of alloferon-1 also suppressed the expression of the inflammatory cytokines in the inflamed paw tissues such as tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein 1 (MCP1), interleukin-5 (IL-5), etc. detected by Luminex liquid chip. Collectively, the present study provides evidences for the marked anti-inflammatory effects of alloferon-1 which might represent new therapeutic options for the treatment of acute inflammatory diseases.

Lignans as Pharmacological Agents in Disorders Related to Oxidative Stress and Inflammation: Chemical Synthesis Approaches and Biological Activities

Plant lignans exhibit a wide range of biological activities, which makes them the research objects of potential use as therapeutic agents. They provide diverse naturally-occurring pharmacophores and are available for production by chemical synthesis. A large amount of accumulated data indicates that lignans of different structural groups are apt to demonstrate both anti-inflammatory and antioxidant effects, in many cases, simultaneously. In this review, we summarize the comprehensive knowledge about lignan use as a bioactive agent in disorders associated with oxidative stress and inflammation, pharmacological effects in vitro and in vivo, molecular mechanisms underlying these effects, and chemical synthesis approaches. This article provides an up-to-date overview of the current data in this area, available in PubMed, Scopus, and Web of Science databases, screened from 2000 to 2022.

Effects of different doses of complete Freund's adjuvant on nociceptive behaviour and inflammatory parameters in polyarthritic rat model mimicking rheumatoid arthritis

Complete Freund's adjuvant (CFA) has been used to develop the arthritic or inflammatory condition in the animal, but there is a lack of information concerning high CFA doses on nociceptive behaviour and inflammatory parameters. This study aimed to compare the effects of different high doses of CFA in rat to closely mimic nociceptive and inflammatory parameters of rheumatoid arthritis (RA) in humans. Twenty-four male Sprague-Dawley rats were randomly divided into four groups (n = 6): Control (C), CFA-induced polyarthritic groups at 5.0 mg/mL (CFA 5.0), 7.5 mg/mL (CFA 7.5) and 10.0mg/mL (CFA 10.0). The rats' right hindpaw was inoculated with CFA intradermally and developed into a polyarthritic state within 20 days. Nociceptive behavioural assessments, including von Frey and hot plate tests and spontaneous activities, were conducted on day 0, 7, 15 and 20. Bilateral ankle joints diameter and circumference, full blood count, joints and paw histological examinations were also conducted throughout the study period. Based on the results, CFA 5.0 and CFA 7.5 groups showed a significant increase in spontaneous activities and development of thermal hyperalgesia but no change in body weight and food intake, no development of tactile allodynia and haematological indices, and no significant morphological changes of joints histology. Meanwhile, CFA 10.0 group demonstrated significant and constant changes in all nociceptive and inflammatory parameters investigated. In conclusion, CFA at the dose of 10mg/mL has the most potential and reliable dosage to develop polyarthritis in a rat model to mimic RA condition in humans.

Schisandrin A protects against isoproterenol‑induced chronic heart failure via miR‑155

Schisandrin A (Sch A) has a protective effect on cardiomyocytes. Circulating miR-155 levels are related to chronic heart failure (CHF). The present study aimed to clarify the role and the molecular mechanism of Sch A in CHF. C57BL/6JGpt mice were used for an isoproterenol (ISO)-induced CHF model to collect heart samples. Echocardiography was employed to detect heartbeat indicators. The degree of myocardial hypertrophy was evaluated based on the measurement of heart weight (HW), body weight (BW) and tibia length (TL) and the observation using hematoxylin-eosin staining. Sprague-Dawley rats were purchased for the separation of neonatal rat ventricular myocytes (NRVMs), which were treated with ISO for 24 h. Transfection regulated the level of miR-155. The viability of NRVMs was detected via MTT assay. The mRNA and protein levels were measured via reverse transcription-quantitative PCR and western blotting and immunofluorescence was used to detect the content of α-smooth muscle actin (α-SMA). Treatment with ISO resulted in rising left ventricular posterior wall thickness, intra-ventricular septum diastole, left ventricular end diastolic diameter, left ventricular end systolic diameter, HW/BW, HW/TL and falling ejection fraction and fractional shortening, the trend of which could be reversed by Sch A. Sch A ameliorated myocardial hypertrophy in CHF mice. In addition, Sch A inhibited ISO-induced upregulated expressions of atrial natriuretic peptide, B-type natriuretic peptide, B-myosin heavy chain and miR-155 in myocardial tissue. Based on the results in vitro, Sch A had no significant effect on the viability of NRVMs when its concentration was <24 µmol/l. Sch A inhibited the levels of miR-155, α-SMA and the phosphorylation levels of AKT and cyclic AMP response-element binding protein (CREB) in ISO-induced NRVMs, which was reversed by the upregulation of miR-155. Schisandrin A mediated the AKT/CREB signaling pathway to prevent CHF by regulating the expression of miR-155, which may shed light on a possible therapeutic target for CHF.

Comparative Analysis of the Antioxidative and Hepatoprotective Activities of Dimethyl Diphenyl Bicarboxylate in Four Animal Models of Hepatic Injury

As a well-known hepatoprotective and antioxidant agent, dimethyl diphenyl bicarboxylate (DDB) has frequently been employed to remedy various liver diseases. However, it is still uncertain whether DDB exerts consistent hepatoprotective and antioxidative activities against varying degrees of hepatic damage. Therefore, DDB (100, 25, 5, or 50 mg/kg depending on the model) was administered to animals in four representative models of liver injury (CCl₄ chemical acute model, DMN subchronic model, TAA chronic model, and restraint stress psychological acute model). Horizontal comparative analysis indicated that DDB significantly lowered the excess serum AST and ALT levels in the CCl₄ and DMN models but not in the TAA and restraint stress models. In accordance with this result, DDB markedly reduced oxidative stress indices (hepatic MDA and ROS) but restored five main antioxidant components (GSH content, GSH-peroxidase, GSH-reductase, SOD, and catalase activity) in the CCl₄ and DMN models. DDB failed to normalize oxidative stressors in the restraint stress-induced injury model and restore these five antioxidant components in the TAA model. Overall, our results produced a comprehensive overview of the effects of DDB on oxidative stressors and the main antioxidative components using four animal models. These findings will provide valuable clues to guide therapeutic clinical applications.

Therapeutic effect of Schisandrin A on avian colibacillosis through gut-liver axis

This study evaluated the therapeutic efficacy of Schisandrin A on systemic colibacillosis of chickens. One hundred and eighty, 1-day-old Hailan Brown chickens were divided into 6 groups of 30 chickens each and assigned to the following treatments: 1) uninfected/untreated control; 2) infected Escherichia coli; 3) infected-plus low dose of Schisandrin A therapy (50 mg/kg); 4) infected-plus medium dose of Schisandrin A therapy (100 mg/kg); 5) infected-plus high dose of Schisandrin A therapy (200 mg/kg) and 6) infected-plus antimicrobial therapy (florfenicol). Each group of chickens was placed in cages with a photoperiod of 12 h of light and 12 h of dark. Feed and water for all groups were provided ad libitum for the duration of the study. On d 14, all the chickens except the uninfected control group were intraperitoneally inoculated with a fresh culture of E. coli containing 1 × 10⁸ CFU/mL. The parameters measured included: average daily weight gain (ADG), percent survivability, liver index, serum activity of enzymes (ALT and AST), hepatic and intestinal concentrations of TNF-α, IL-1β, IL-6, IL-8, and LPS, expression of tight junction proteins (occludin, ZO-1, and claudin-1), relative abundance of bacterial species and histopathological changes in hepatic and intestinal tissue. The results showed that the medium and high doses of Schisandrin A ameliorated the detrimental effects of colibacillosis on weight gain. Regarding organ indexes, E. coli infection induced a significant increase in liver index, all the doses of Schisandrin A produced a significant reduction of liver index in comparison to the E. coli infected control. Serum activity of ALT and AST enzymes significantly increased due to E. coli infection, with the exception of the low dose of Schisandrin A for AST enzyme activity, all the Schisandrin A treatments significantly lowered enzyme activity in comparison to the E. coli infected control. Regarding concentrations of inflammatory markers in hepatic and intestinal, E. coli infection caused a significant increase in TNF-α, IL-1β, IL-6, and IL-8, except the lowest dose of Schisandrin A for IL-1β, the rest of the doses tested were able to significantly reduced the concentrations of inflammatory markers. Concentrations of LPS in hepatic and intestinal tissues were significantly increased by E. coli infection, all doses of Schisandrin A significantly reduced the concentration of LPS in hepatic and intestinal tissue. E. coli infection significantly reduced the expression of 2 tight junction proteins (ZO-1 and Claudin-1), the higher doses of Schisandrin A were effective in significantly increasing the expression of these tight junction proteins when compared with the E. coli infected control. Taken together, these results show that Schisandrin A has potential as an alternative therapy for the treatment of colibacillosis in chickens.

Pharmacodynamic effects and molecular mechanisms of lignans from Schisandra chinensis Turcz. (Baill.), a current review

Fruit of Schisandra chinensis Turcz. (Baill.) (S. chinensis) is a traditional herbal medicine widely used in China, Korea, and many other east Asian countries. At present, S. chinensis commonly forms Chinese medicinal formulae with other herbal medicines to treat liver disease and neurological disease in clinical. Modern researches indicated that lignans were the main active ingredients of S. chinensis with high content and novel dibenzocyclooctadiene skeletal structure, exhibited considerable antioxidant, anti-inflammatory, and neuroprotective properties. Additionally, some of these lignans also showed certain potentials in anti-cancer, anti-fibrosis, and other effects. In the current review, we summarize literature reported lignans from S. chinensis in the past five years, and highlight the molecular mechanisms of lignans in exerting their biological functions. Also, we point out some deficiencies of existing researches and discuss the future direction of lignans study.