Anti-hyperalgesia effect of nanchelating based nano particle, RAc1, can be mediated via liver hepcidin expression modulation during persistent inflammation

Iron metabolism and arthritis: Exploring connections and therapeutic avenues

ABSTRACT

Iron is indispensable for the viablility of nearly all living organisms, and it is imperative for cells, tissues, and organisms to acquire this essential metal sufficiently and maintain its metabolic stability for survival. Disruption of iron homeostasis can lead to the development of various diseases. There is a robust connection between iron metabolism and infection, immunity, inflammation, and aging, suggesting that disorders in iron metabolism may contribute to the pathogenesis of arthritis. Numerous studies have focused on the significant role of iron metabolism in the development of arthritis and its potential for targeted drug therapy. Targeting iron metabolism offers a promising approach for individualized treatment of arthritis. Therefore, this review aimed to investigate the mechanisms by which the body maintains iron metabolism and the impacts of iron and iron metabolism disorders on arthritis. Furthermore, this review aimed to identify potential therapeutic targets and active substances related to iron metabolism, which could provide promising research directions in this field.

Analysis of Hepatic Lipid Metabolism and Immune Function During the Development of Collagen-Induced Arthritis

The liver is essential for metabolic and immune functions and has been linked to systemic inflammatory diseases. However, the role of the liver is still elusive during the development of rheumatoid arthritis (RA), although there have been indeed some reports. We used label-free quantitative proteomics and experimental verification in this study to reveal the hepatic lipid metabolism and immune function during collagen-induced arthritis (CIA) development. The proteomics results revealed that the role of the liver differs in different phases of CIA rats. In terms of specific performance, hepatic lipid metabolism, which is primarily concerned with cholesterol, triacylglycerol, and phospholipid, was significantly influenced in the CIA induction phase, whereas the immune function, which includes binding of granulocytes, adhesion of immune cells, etc., was affected considerably at the peak phase of CIA rats compared to normal rats. Finally, the hepatic dynamic changes in CIA rats were further confirmed using targeted metabolomics and ELISA. We found that most fatty acids of the liver in the CIA induction phase were significantly decreased, and proteins related to complement activation and migration or adhesion of immune cells including C3, MMP-8, CTSZ, and S100A9 were significantly increased in the liver of CIA rats in the peak phase. Our findings indicated that the lipid metabolism and immune function of the liver were influenced in CIA rats. Thus, the conditions of the liver during RA development should be considered in therapeutic and nutritional interventions.

Euphorbia factor L3 ameliorates rheumatoid arthritis by suppressing the inflammatory response by targeting Rac family small GTPase 1

Euphorbia factor L3 (EFL3) is extracted from Euphorbia lathyris and is known for its anti-inflammatory properties. This study focused on the potential anti-inflammatory and therapeutic effects of EFL3 on rheumatoid arthritis (RA) using fibroblast-like synoviocytes (FLSs) and arthritis animal models. Functional analysis showed that EFL3 could ameliorate the inflammatory phenotype of FLSs derived from RA patients, as evidenced by the decreases in cell viability, migration, invasion and cytokine production. Luciferase activity, Western blotting and immunofluorescence assays demonstrated that EFL3 inhibited the nuclear translocation of the p65 subunit and the subsequent activation of the nuclear factor kappa-Β (NF-κB) pathway. Furthermore, the therapeutic effects of EFL3 against arthritic progression were evidenced by decreases in joint swelling, arthritis scores, inflammatory factor production, synovial hyperplasia, and bone destruction in collagen-induced arthritis (CIA) and tumor necrosis factor-α (TNF-α) transgenic (TNF-tg) mouse models. Molecular analysis identified Rac family small GTPase 1 (Rac1) as the potential target that was required for EFL3-mediated suppression of the inflammatory RA FLS phenotype. In summary, this study uncovered the therapeutic potential of EFL3 in RA, which suggests its future clinical use.

Carbamylated erythropoietin improves recognition memory by modulating microglia in a rat model of pain

Patients with chronic pain often complain about memory impairments. Experimental studies have shown neuroprotective effects of Carbamylated erythropoietin (Cepo-Fc) in the treatment of cognitive dysfunctions. However, little is currently known about its precise molecular mechanisms in a model of inflammatory pain. Therefore, this study aimed to investigate neuroprotective effects of Cepo-Fc against cognitive impairment induced by the inflammatory model of Complete Freund's Adjuvant (CFA). Carbamylated erythropoietin was administrated Intraperitoneally (i.p) on the day CFA injection, continued for a 21-days period. After conducting the behavioral tests (thermal hyperalgesia and novel object recognition test), western blot and ELISA were further preformed on days 0, 7, and 21. The results of this study indicate that Cepo-Fc can effectively reverse the CFA induced thermal hyperalgesia and recognition memory impairment. Additionally, Cepo-Fc noticeably decreased the hippocampal microglial expression, production of hippocampal IL-1β, and hippocampal apoptosis and necroptosis induced by the inflammatory pain. Therefore, our findings suggest that neuroprotective effects of Cepo-Fc in the treatment of pain related recognition memory impairment may be mediated through reducing hippocampal microglial expression as well as IL-1β production.

Noopept; a nootropic dipeptide, modulates persistent inflammation by effecting spinal microglia dependent Brain Derived Neurotropic Factor (BDNF) and pro-BDNF expression throughout apoptotic process

There are largely unknown associations between changes in pain behavior responses during persistent peripheral inflammation and spinal cell alteration such as apoptosis. Some evidence suggests that microglia and microglia related mediators play notable roles in induction and maintenance of central nervous system pathologies and inflammatory pain. By considering those relationships and microglia related nootrophic factors, such as the Brain Derived Neurotrophic Factor (BDNF) in CNS, we attempted to assess the relationship between microglia dependent BDNF and its precursor with pain behavior through spinal cell apoptosis as well as the effect of Noopept on this relationship. Persistent peripheral inflammation was induced by a single subcutaneous injection of Complete Freund's Adjuvant (CFA) on day 0. Thermal hyperalgesia, paw edema, microglial activity, microglia dependent BDNF, pro-BDNF expression, and apoptosis were assessed in different experimental groups by confirmed behavioral and molecular methods on days 0, 7, and 21 of the study. Our findings revealed hyperalgesia and spinal cell apoptosis significantly increased during the acute phase of CFA-induced inflammation but was then followed by a decrement in the chronic phase of the study. Aligned with these variations in spinal microglial activity, microglia dependent BDNF significantly increased during the acute phase of CFA-induced inflammation. Our results also indicated that daily administration of Noopept (during 21 days of the study) not only caused a significant decrease in hyperalgesia and microglia dependent BDNF expression but also changed the apoptosis process in relation to microglia activity alteration. It appears that the administration of Noopept can decrease spinal cell apoptosis and hyperalgesia during CFA-induced inflammation due to its direct effects on microglial activity and microglia dependent BDNF and pro-BDNF expression.

DIBc nano metal-organic framework improves biochemical and pathological parameters of experimental chronic kidney disease

BACKGROUND

The growing morbidity and mortality rate of chronic kidney disease (CKD) has forced researchers to find more efficient strategies for controlling this disease. Studies have proven the important role of alteration in iron, zinc and selenium metabolism in CKD pathological process. Nanotechnology, through synthetizing nano metal-organic framework (NMOF) structures, can be employed as a valuable strategy for using these trace elements as the key for modification and improvement of CKD-related pathological events. After proving the anti-diabetic property of DIBc NMOF (which contains selenium and zinc) in the previous study, the impact of this NMOF on some important biochemical and pathological parameters of CKD was evaluated in the current study.

METHODS

Knowing that diabetic nephropathy (DN) is the leading cause of CKD, male wistar rats were selected and given a high fat diet for 2 weeks and then were injected with streptozotocin (35 mg/kg) to induce DN. Six weeks after streptozotocin injection, DIBc or metformin treatment started and continued for 8 weeks.

RESULTS

Eight weeks of DIBc treatment decreased plasma fasting blood glucose, blood urea nitrogen, uric acid, malondialdehyde (MDA) and HOMA-IR index compared to DN control and metformin groups. This NMOF significantly reduced urinary albumin excretion rate, MDA and 8-isoprostane, while it increased creatinine clearance in comparison to the above-mentioned groups. Renal histo-pathological images indicated that DIBc ameliorated glomerular basement membrane thickening and wrinkling, mesangial matrix expansion and hypercellularity and presence of intra-cytoplasmic hyaline droplets in proximal cortical tubules of kidney samples.

CONCLUSION

The results showed the therapeutic effect of DIBc on important biochemical and histo-pathological parameters of CKD, so this NMOF could be regarded as a promising novel anti-CKD agent.

miR-488 mediates negative regulation of the AKT/NF-κB pathway by targeting Rac1 in LPS-induced inflammation

Endometritis is an inflammatory change in the structure of the endometrium due to various causes and is a common cause of infertility. Studies have confirmed that microRNAs (miRNAs) play a key regulatory role in various inflammatory diseases. However, the miRNA-mediated mechanism of endometrial inflammation induced by lipopolysaccharides (LPS) remains unclear. In this study, real-time quantitative polymerase chain reaction, Western blot analysis, immunofluorescence and Rac family small GTPase 1 (Rac1) interference were used to reveal the overexpression of miR-488 in the LPS-induced bovine uterus, and the effect of protein kinase B κ-light chain enhancement of the nuclear factor-activated B cells (AKT/NF-κB) pathway in intimal epithelial cells. The results showed that the expression of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in the experimental group was significantly lower than that in the control group when miR-488 was overexpressed. Similar results were observed in the expression levels of p-AKT, p-IKK, and p-p65 proteins. In addition, the dual-luciferase reporter system confirmed that miRNA-488 may directly target the 3'-untranslated region of Rac1. In turn, the expression of Rac1 was inhibited. Moreover, the nuclear translocation of NF-κB was inhibited, and meanwhile, the accumulation of reactive oxygen species (ROS) in the cells was reduced. Thus, we provide basic data for the negative regulation of miR-488 in LPS-induced inflammation by inhibiting ROS production and the AKT/NF-kB pathway in intimal epithelial cells.