Protective effects of evening primrose oil on behavioral activities, nigral microglia and histopathological changes in a rat model of rotenone-induced parkinsonism

Morin alleviates DSS-induced ulcerative colitis in mice via inhibition of inflammation and modulation of intestinal microbiota

Ulcerative colitis (UC) is a chronic inflammatory condition with recurrent and challenging symptoms. Effective treatments are lacking, making UC management a critical research area. Morin (MO), a flavonoid from the Moraceae family, shows potential as an anti-UC agent, but its mechanisms are not fully understood. Using a dextran sulfate sodium (DSS)-induced UC mouse model, we employed network pharmacology to predict MO's therapeutic effects. Assessments included changes in body weight, disease activity index (DAI), and colon length. Immunofluorescence, hematoxylin and eosin (H&E), and PAS staining evaluated colon damage. ELISA and western blot analyzed inflammatory factors, tight junction (TJ)-associated proteins (Claudin-3, Occludin, ZO-1), and Mitogen-Activated Protein Kinase (MAPK)/ Nuclear Factor kappa B (NF-κB) pathways. 16S rRNA sequencing assessed gut microbiota diversity, confirmed by MO's modulation via Fecal Microbial Transplantation (FMT). Early MO intervention reduced UC severity by improving weight, DAI scores, and colon length, increasing goblet cells, enhancing barrier function, and inhibiting MAPK/NF-κB pathways. MO enriched gut microbiota, favoring beneficial bacteria like Muribaculaceae and Erysipelotrichaceae while reducing harmful Erysipelotrichaceae and Muribaculaceae. This study highlights MO's potential in UC management through inflammation control, mucosal integrity maintenance, and gut flora modulation.

Effect of mesenchymal stem cells and melatonin on experimentally induced peripheral nerve injury in rats

Injury of a peripheral nerve (PNI) leads to both ischemic and inflammatory alterations. Sciatic nerve injury (SNI) represents the most widely used model for PNI. Mesenchymal stem cell-based therapy (MSCs) has convenient properties on PNI by stimulating the nerve regeneration. Melatonin has cytoprotective activity. The neuroprotective characteristics of MSCs and melatonin separately or in combination remain a knowledge need. In the rats-challenged SNI, therapeutic roles of intralesional MSCs and intraperitoneal melatonin injections were evaluated by functional assessment of peripheral nerve regeneration by walking track analysis involving sciatic function index (SFI) and two electrophysiological tests, electromyography and nerve conduction velocity, as well as measurement of antioxidant markers in serum, total antioxidant capacity (TAC) and malondialdehyde, and mRNA expression of brain derived neurotrophic factor (BDNF) in nerve tissues in addition to the histopathological evaluation of nerve tissue. Both individual and combination therapy with MSCs and melatonin therapies could effectively ameliorate this SNI and promote its regeneration as evidenced by improving the SFI and two electrophysiological tests and remarkable elevation of TAC with decline in lipid peroxidation and upregulation of BDNF levels. All of these led to functional improvement of the damaged nerve tissues and good recovery of the histopathological sections of sciatic nerve tissues suggesting multifactorial synergistic approach of the concurrent usage of melatonin and MSCs in PNI. The combination regimen has the most synergistic neuro-beneficial effects in PNI that should be used as therapeutic option in patients with PNI to boost their quality of life.

Re-positioning of low dose paclitaxel against depressive-like behavior and neuroinflammation induced by lipopolysaccharide in rats: Crosstalk between NLRP3/caspase-1/IL-1β and Sphk1/S1P/ NF-κB signaling pathways

AIMS

Depression is a potentially fatal illness affecting millions of individuals worldwide, across all age groups. Neuroinflammation is a key factor in depression development. Paclitaxel (PXL), a well-known chemotherapeutic agent has been used as therapy for several types of cancer. This study aims to evaluate the ameliorative effect of low-dose PXL against lipopolysaccharide (LPS)-induced depression in rats.

MATERIALS AND METHODS

Adult male Sprague-Dawley rats were administrated a single dose of LPS (5 mg/kg, i.p.); 2 h later, rats received PXL (0.3 mg/kg, i.p. three times/week) for one week.

KEY FINDINGS

Low-dose PXL alleviated LPS-induced depressive-like behavior in rats as evidenced by significantly improving behavioral changes in both forced swim test (FST) and open field test (OFT), successfully mitigated depletion of monoamines (serotonin, norepinephrine, and dopamine), in addition to markedly decreasing lipid peroxidation with antioxidant levels elevation in brain tissues. Low-dose PXL substantially decreased inflammation triggered by LPS in brain tissue via repressing the expression of NLRP3 and its downstream markers level, caspase-1 and IL-1β jointly with a corresponding decrease in proinflammatory cytokine levels (TNF-α). Furthermore, low-dose PXL remarkably down-regulated Sphk1/S1P signaling pathway. Concurrent with these biochemical findings, there was a noticeable improvement in the brain tissue's histological changes.

SIGNIFICANCE

These findings prove the role of low-dose PXL in treatment of LPS-induced neuroinflammation and depressive-like behavior through their anti-depressant, antioxidant and anti-inflammatory actions. The suggested molecular mechanism may entail focusing the interconnection among Sphk1/S1P, and NLRP3/caspase-1/IL-1β signaling pathways. Hence PXL could be used as a novel treatment against LPS-induced depression.

Chemical composition and studying the possible neuroprotective effect of iridoids-rich fraction from Pentas lanceolata leaves using rotenone model of Parkinson's disease in mice

Parkinsonism is an age-related neurodegenerative illness that affects motor coordination leading to loss of dopaminergic neurons. Many medications are used for the treatment of Parkinson's disease but are only symptomatic and have a limited effect on the progression of this ailment. Therefore, bioactive compounds which derived from plants have been examined for their ability to improve the neuronal damage and cell death happened in parkinsonian patients. In this study the iridoids-rich fraction isolated from Pentas lanceolata (PIRF) leaves was investigated for its phytoconstituents. Seven iridoids (1-7) and one flavonol diglycoside (8) were isolated, and their chemical structures were achieved by 1H and 13C nuclear magnetic resonance and ESI-MS spectral data. Compound 1 (6β,7β-epoxy-8-epi-splendoside) and 5 (gaertneroside) were isolated for the first time from Pentas genus as well as compound 8 (kaempferol-3-O-robinobioside). The current study aims to investigate the possible anti-parkinsonian effect of PIRF using a rotenone model of Parkinsonism in mice. Behavioural tests (wirehanging, stair and wooden-walking tests) were done to examine the motor coordination in mice after treatment. Biochemical and histopathological examinations for brain striatum in different groups were also evaluated. Results revealed that rotenone-treated mice had poor motor functions described by depletion of dopamine and Ach levels, a significant increase in proinflammatory cytokines, IL-1B, TNF-α and Mcp-1 and oxidative biomarkers with subsequent reduction in antioxidant mediators. Disorganization of striatum, degenerated neurocytes, slight vacuolation, shrunken neurons with pyknotic nuclei and apoptotic cells are displayed by histopathological examinations. Treatment with PIRF ameliorates the neurodegeneration-induced by rotenone in the brain of mice. The anti-parkinsonian effect of PIRF could be attributed to their bioactive constituents of iridoids.

3,3',4,4'-tetrachlorobiphenyl (PCB77) enhances human Kv1.3 channel currents and alters cytokine production

Polychlorinated biphenyls (PCBs) were once used throughout various industries; however, because of their persistence in the environment, exposure remains a global threat to the environment and human health. The Kv1.3 and Kv1.5 channels have been implicated in the immunotoxicity and cardiotoxicity of PCBs, respectively. We determined whether 3,3',4,4'-tetrachlorobiphenyl (PCB77), a dioxin-like PCB, alters human Kv1.3 and Kv1.5 currents using the Xenopus oocyte expression system. Exposure to 10 nM PCB77 for 15 min enhanced the Kv1.3 current by approximately 30.6%, whereas PCB77 did not affect the Kv1.5 current at concentrations up to 10 nM. This increase in the Kv1.3 current was associated with slower activation and inactivation kinetics as well as right-shifting of the steady-state activation curve. Pretreatment with PCB77 significantly suppressed tumor necrosis factor-α and interleukin-10 production in lipopolysaccharide-stimulated Raw264.7 macrophages. Overall, these data suggest that acute exposure to trace concentrations of PCB77 impairs immune function, possibly by enhancing Kv1.3 currents.

Protective effects of functional Nano-Selenium supplementation on spleen injury through regulation of p38 MAPK and NF-κB protein expression

Selenium (Se) is a trace element necessary for humans to maintain normal physiological activities, and Se deficiency may lead to splenic injury, while Se supplementation can alleviate splenic injury. However, the mechanism is unclear. In this study, we constructed a Se deficiency animal model by feeding Sprague-Dawley (SD) rats with low Se feed. Meanwhile, we observed the repairing effect of Se supplementation on splenic injury with two doses of novel nano-selenium (Nano-Se) supplement by gavage. We measured the Se content in the spleens of the rats by atomic fluorescence spectroscopy (AFS) method and combined the results of hematoxylin-eosin (HE) and Masson staining to observe the splenic injury, comprehensively evaluating the construction of the animal model of low selenium-induced splenic injury. We measured the mRNA and protein expression levels of p38 mitogen-activated protein kinase (p38 MAPK), nuclear factor kappa-B (NF-κB), and interleukin-6 (IL-6) in the spleen by Real-time quantitative polymerase chain reaction (qPCR), western blot (WB), and immunohistochemistry (IHC). We found that the Se deficiency group exhibited lower Se content, splenic fibrosis, and high expression of p38 MAPK, NF-κB, and IL-6 compared to the normal group. The Se supplement groups exhibited higher Se content, attenuated splenic injury, and down-regulated expression of p38 MAPK, NF-κB, and IL-6 relative to the Se deficiency group. This study suggests that Se deficiency leads to splenic injury in rats, and Se supplementation may attenuate splenic injury by inhibiting the expression of p38 MAPK, NF-κB and IL-6.

Wuling capsule modulates macrophage polarization by inhibiting the TLR4-NF-κB signaling pathway to relieve liver fibrosis

BACKGROUND AND PURPOSE

Wuling capsule (WL) has good efficacy in the clinical treatment of chronic hepatitis B and liver injury. Liver fibrosis is a common pathological feature of chronic liver disease and may progress to irreversible cirrhosis and liver cancer. Accumulating evidence reveals that modulating macrophage polarization contribute to the therapy of liver fibrosis. However, the effects of WL on modulating macrophage polarization to relive liver fibrosis remain unclear. This study investigated the anti-liver fibrosis effects of WL in carbon tetrachloride (CCl4)-induced liver fibrosis in rats, and the modulation effects and underlying molecular mechanism on macrophage polarization.

METHODS

A rat liver fibrosis model was constructed by intraperitoneal injection of 40 % CCl4 olive oil mixture. At 2, 4, 6, and 8 weeks, the histopathological status of the liver was assessed by hematoxylin-eosin (HE) and Masson staining; the liver biochemical indexes were measured in rat liver tissue. The expression levels of inflammatory cytokines in liver tissue were detected by ELISA. The mRNA levels and proteins expression of macrophage markers of different phenotypes, TLR4-NF-κB signaling pathway indicators were detected independently by ELISA, immunofluorescence, RT-PCR and western blotting.

RESULTS

In vivo, WL treatment attenuated abnormal changes in weight, organ indices and biochemical indices, alleviated pathological changes, and reduced collagen fiber deposition as well as the expression of α-SMA in liver tissues. Further studies revealed that WL decreased the expression of the macrophage M1 polarization markers inducible nitric oxide synthase (iNOS), TNF-α, IL-6, and CD86, promoted the expression of the M2 macrophage polarization markers IL-10, CD206, and arginase-1 (Arg-1), and inhibited the activation of the TLR4-NF-κB signaling pathway via several key signaling proteins. In vitro, WL significantly suppressed macrophage M1 polarization, and promoted M2 polarization while boosted M1 polarization transform to M2 polarization in LPS-activated RAW264.7 cells.

CONCLUSIONS

This study demonstrated that WL modulated macrophage polarization against liver fibrosis mainly by inhibiting the activation of the TLR4-NF-κB signaling pathway.

Uncovering the colorectal cancer immunotherapeutic potential: Evening primrose (Oenothera biennis) root extract and its active compound oenothein B targeting the PD-1/PD-L1 blockade

BACKGROUND

The emergence of immune checkpoint inhibitors, a novel class of immunotherapy drugs, represents a major breakthrough in cancer immunotherapy, substantially improving patient survival post-treatment. Blocking programmed death-ligand 1 (PD-L1) and programmed death protein-1 (PD-1) has demonstrated promising clinical results in various human cancer types. The US FDA has recently permitted only monoclonal antibody (mAb)-based PD-L1 or PD-1 blockers. Although these antibodies exhibit high antitumor efficacy, their size- and affinity-induced side effects limit their applicability.

PURPOSE

As small-molecule-based PD-1/PD-L1 blockers capable of reducing the side effects of antibody therapies are needed, this study focuses on exploring natural ingredient-based small molecules that can target hPD-L1/PD-1 using herbal medicines and their components.

METHODS

The antitumor potential of evening primrose (Oenothera biennis) root extract (EPRE), a globally utilized traditional herbal medicine, folk remedy, and functional food, was explored. A coculture system was established using human PD-L1-expressed murine MC38 cells (hPD-L1-MC38s) and CD8+ tumor-infiltrating T lymphocytes (CD8+ TILs) expressing humanized PD-1. The in vivo experiments utilized a colorectal cancer (CRC) C57BL/6 J mouse model bearing MC38 cells expressing humanized PD-L1 and PD-1 proteins.

RESULTS

EPRE and its active compound oenothein B effectively hindered the molecular interaction between hPD-L1 and hPD-1. EPRE stimulated tumor-specific T lymphocytes of a hPD-L1/PD-1 CRC mice. This action resulted in the elevated infiltration of cytotoxic CD8+T lymphocytes and subsequent tumor growth reduction. Moreover, the combined therapy of oenothein B, a PD-1/PD-L1 blocker, and FOLFOX (5-fluorouracil plus oxaliplatin) cooperatively suppressed hPD-L1-MC38s growth in the ex vivo model through activated CD8+ TIL antitumor immune response. Oenothein B exhibited a high binding affinity for hPD-L1 and hPD-1. We believe that this study is the first to uncover the inhibitory effects of EPRE and its component, oenothein B, on PD-1/PD-L1 interactions.

CONCLUSION

This study identified a promising small-molecule candidate from natural products that blocks the hPD-L1/PD-1 signaling pathway. These findings emphasize the potential of EPRE and oenothein B as effective anticancer drugs.

Stattic ameliorates the cecal ligation and puncture-induced cardiac injury in septic mice via IL-6-gp130-STAT3 signaling pathway

AIM

Sepsis-induced cardiac dysfunction is the leading cause of higher morbidity and mortality with poor prognosis in septic patients. Our recent previous investigation provides evidence of the hallmarks of signal transducer and activator of transcription3 (STAT3) activation in sepsis and targeting of STAT3 with Stattic, a small-molecule inhibitor of STAT3, has beneficial effects in various septic tissues. We investigated the possible cardioprotective effects of Stattic on cardiac inflammation and dysfunction in mice with cecal ligation and puncture (CLP)-induced sepsis.

MAIN METHODS

A polymicrobial sepsis model was induced by CLP in mice and Stattic (25 mg/kg) was intraperitoneally given at one and twelve hours after CLP operation. The cecum was exposed in sham-control mice without CLP. After 18 h of surgery, electrocardiogram (ECG) for anaesthized mice was registered followed by collecting of samples of blood and tissues for bimolecular and histopathological assessments. Myeloperoxidase, a marker of neutrophil infiltration, was assessed immunohistochemically.

KEY FINDINGS

CLP profoundly impaired cardiac functions as evidenced by ECG changes in septic mice as well as elevation of cardiac enzymes, and inflammatory markers with myocardial histopathological and immunohistochemical alterations. While, Stattic markedly reversed the CLP-induced cardiac abnormalities and restored the cardiac function by its anti-inflammatory activities.

SIGNIFICANCE

Stattic treatment had potential beneficial effects against sepsis-induced cardiac inflammation, dysfunction and damage. Its cardioprotective effects were possibly attributed to its anti-inflammatory activities by targeting STAT3 and downregulation of IL-6 and gp130. Our investigations suggest that Stattic could be a promising target for management of cardiac sepsis and inflammation-related cardiac damage.

The immunomodulatory effects of probiotics and azithromycin in dextran sodium sulfate-induced ulcerative colitis in rats via TLR4-NF-κB and p38-MAPK pathway

Ulcerative colitis (UC), a chronic autoimmune disease of the gut with a relapsing and remitting nature, considers a major health-care problem. DSS is a well-studied pharmacologically-induced model for UC. Toll-Like Receptor 4 (TLR4) and its close association with p-38-Mitogen-Activated Protein Kinase (p-38 MAPK) and nuclear factor kappa B (NF-κB) has important regulatory roles in inflammation and developing UC. Probiotics are gaining popularity for their potential in UC therapy. The immunomodulatory and anti-inflammatory role of azithromycin in UC remains a knowledge need. In the present rats-established UC, the therapeutic roles of oral probiotics (60 billion probiotic bacteria per kg per day) and azithromycin (40 mg per kg per day) regimens were evaluated by measuring changes in disease activity index, macroscopic damage index, oxidative stress markers, TLR4, p-38 MAPK, NF-κB signaling pathway in addition to their molecular downstream; tumor necrosis factor alpha (TNFα), interleukin (IL)1β, IL6, IL10 and inducible nitric oxide synthase (iNOS). After individual and combination therapy with probiotics and azithromycin regimens, the histological architecture of the UC improved with restoration of intestinal tissue normal architecture. These findings were consistent with the histopathological score of colon tissues. Each separate regimen lowered the remarkable TLR4, p-38 MAPK, iNOS, NF-κB as well as TNFα, IL1β, IL6 and MDA expressions and elevated the low IL10, glutathione and superoxide dismutase expressions in UC tissues. The combination regimen possesses the most synergistic beneficial effects in UC that, following thorough research, should be incorporated into the therapeutic approach in UC to boost the patients' quality of life.

Inhalation exposure to crude oil vapor induces behavioural deficits by increasing oxidative stress and histopathological changes in rat hippocampus: Quercetin therapeutic approach

OBJECTIVE

Inhalation exposure to crude oil vapor (COV) and petroleum products is considered responsible for neurobehavioral toxicity in human and animal models. The antioxidant activity of quercetin (Que) and its derivatives are promising for protecting the hippocampus. This study aimed to evaluate the neuroprotective role of Que against COV-induced behavioral alterations and hippocampus damage.

METHODS

Eighteen adult male Wistar rats were randomly divided into the following three groups (n = 6): the control, the COV, and the COV + Que group. The inhalation method was used to expose the rats to crude oil vapors for 5 h daily, and Que (50 mg/kg) was administered orally. After 30 days of treatment, the spatial working memory and anxiety levels were evaluated using the cross-arm maze and elevated plus maze (EPM), respectively. TUNEL assay and hematoxylin-eosin (H&E) staining were used to identify the necrosis, normal and apoptotic cells in the hippocampus. Moreover, the levels of oxidative stress biomarkers including malondialdehyde (MDA), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (TAC) were investigated in the hippocampus tissue.

RESULTS

The results indicated that exposure to COV was associated with a significant decrease in spatial working memory and activity of CAT, TAC, SOD, and GPx enzymes compared to the control (P < 0.05). Moreover, COV significantly increased the level of anxiety, MDA, and hippocampal apoptosis (P < 0.05). The simultaneous administration of quercetin along with exposure to COV improved the behavioral alterations, activity of antioxidant enzymes, and hippocampal apoptosis.

CONCLUSIONS

These findings suggest that quercetin prevents COV-induced hippocampal damage by enhancing the antioxidant system and preventing cell apoptosis.