Nitric Oxide Synthase Research Articles

Neuropilin-2-expressing breast cancer cells mitigate radiation-induced oxidative stress through nitric oxide signaling.

The high rate of recurrence after radiation therapy in triple-negative breast cancer (TNBC) indicates that novel approaches and targets are needed to enhance radiosensitivity. Here, we report that neuropilin-2 (NRP2), a receptor for vascular endothelial growth factor (VEGF) that is enriched on subpopulations of TNBC cells with stem cell properties, is an effective therapeutic target for sensitizing TNBC to radiotherapy. Specifically, VEGF/NRP2 signaling induces nitric oxide synthase 2 (NOS2) transcription by a mechanism dependent on Gli1. NRP2-expressing tumor cells serve as a hub to produce nitric oxide (NO), an autocrine and paracrine signaling metabolite, which promotes cysteine-nitrosylation of Kelch-like ECH-associated protein 1 (KEAP1) and, consequently, nuclear factor erythroid 2-related factor 2-mediated (NFE2L2-mediated) transcription of antioxidant response genes. Inhibiting VEGF binding to NRP2, using a humanized mAb, results in NFE2L2 degradation via KEAP1, rendering cell lines and organoids vulnerable to irradiation. Importantly, treatment of patient-derived xenografts with the NRP2 mAb and radiation resulted in significant tumor necrosis and regression compared with radiation alone. Together, these findings reveal a targetable mechanism of radioresistance, and they support the use of NRP2 mAb as an effective radiosensitizer in TNBC.

Promotion of mandibular distraction osteogenesis by parathyroid hormone via macrophage polarization induced through iNOS downregulation

ObjectiveTo investigate whether Parathyroid hormone (PTH) can promote mandibular distraction osteogenesis by regulating macrophage polarization and the underlying mechanisms of this phenomenon. MethodsForty-eight Rabbits were used to establish the mandibular distraction osteogenesis experimental model, randomly divided into 2 groups. Intermittent post-operative injections of 20 μg/kg PTH and normal saline were administered to the experimental and control groups, respectively. Regenerated new bone was examined using HE staining, osteoclast numbers were determined through tartrate-resistant acid phosphatase (TRAP) staining, and macrophage polarization markers arginase 1 (Arg1) and inducible nitric oxide synthase (iNOS) expressions were elucidated using immunohistochemistry (IHC), the mRNA expression of CD206, CD11C, Arg1 and iNOS were detected using qPCR. ResultsThe bone trabeculae in the experimental group were thicker, with a more homogeneous structure and more new osteoid than in the control group. In the area of distraction osteogenesis, the osteoclast count in the experimental group was higher than in the control group (P < 0.05). IHC results indicated differential expressions of Arg1 and iNOS in the experimental group compared to the control group (P < 0.05). Relative mRNA expressions of CD11c and iNOS were lower in the experimental group than in the control group (P < 0.05), whereas the expressions of CD206 and Arg1 mRNA were higher in the experimental group compared to the control group (P < 0.05). ConclusionIntermittent PTH injections increased macrophage quantity in the mandible generated by distraction osteogenesis, downregulated iNOS, upregulated Arg1, and promoted macrophage polarization from M1 to M2 phenotype, thereby promoting mandibular distraction osteogenesis.

Quercetin Prevents Hypertension in Dahl Salt-sensitive Rats F ed a High-salt Diet Through Balancing Endothelial Nitric Oxide Synthase and Sirtuin 1.

A high-salt diet is a leading dietary risk factor for elevated blood pressure and cardiovascular disease. Quercetin reportedly exhibits cardioprotective and antihypertensive therapeutic effects. The objective of this study is to examine the effect of quercetin on high-salt dietinduced elevated blood pressure in Dahl salt-sensitive (SS) rats and determine the underlying molecular mechanism. Rats of the Dahl SS and control SS-13 BN strains were separated into five groups, SS-13 BN rats fed a low-salt diet (BL group), SS-13 BN rats fed a high-salt diet (BH group), Dahl SS rats fed a low-salt diet (SL group), Dahl SS rats fed a high-salt diet (SH group), and SH rats treated with quercetin (SHQ group). Blood pressure was checked three weeks into the course of treatment, and biochemical markers in the urine and serum were examined. Additionally, western blot was done to evaluate the sirtuin 1 (SIRT1) and endothelial nitric oxide synthase (eNOS) expression levels. Immunohistochemical analysis was performed to verify SIRT1 levels. We demonstrated that a high-salt diet elevated blood pressure in both SS-13 BN and Dahl SS rats, and quercetin supplementation alleviated the altered blood pressure. Compared with the SH group, quercetin significantly elevated the protein expression of SIRT1 and eNOS. Immunohistochemistry results further confirmed that quercetin could improve the protein expression of SIRT1. Quercetin reduced blood pressure by enhancing the expression of SIRT1 and eNOS in Dahl SS rats fed a high-salt diet.

Chondroitin sulfate modulates oxidative stress and inflammation in the substantia nigra via gut microbiota regulation: Mechanistic insights into Parkinson's disease treatment

Hydrogen sulfide (H2S) is a bioactive gas with potential neuroprotective properties. This study explores the therapeutic efficacy of chondroitin sulfate (CS) in a Parkinson's disease (PD) mouse model by evaluating its impact on behavior, gut microbiota composition, substantia nigra (SN) pathology, oxidative stress, and inflammation. Behavioral tests indicate that CS improves cognitive function and learning abilities in PD mice. Gut microbiota analysis and fecal H2S content measurement reveal that CS fosters the growth of Desulfovibrio and boosts H2S production, respectively. Further examination shows that CS treatment enhances antioxidant defenses, reduces inducible nitric oxide synthase (iNOS)-mediated inflammation, and alleviates PD-related pathology and α-synuclein overexpression in the SN. These findings suggest that CS modulates the gut microbiota and its metabolic product, H2S, potentially improving PD symptoms through the gut-brain axis.

Study on peripheral antinociception induced by hydrogen peroxide (H2O2): characterization and mechanisms.

The present study aimed to evaluate the possible peripheral H2O2-induced antinociception and determine the involvement of opioidergic, cannabinoidergic and nitrergic systems, besides potassium channels in its antinociceptive effect. Prostaglandin E2 was used to induce hyperalgesia in male Swiss mice using the mechanical paw pressure test. H2O2 (0.1, 0.2, 0.3 µg/paw) promoted a dose-dependent antinociceptive effect that was not observed in contralateral paw. Female mice also showed antinociception in the model. The partial H2O2-induced antinociception was potentiated by the inhibitor of catalase enzyme, aminotriazole (40, 60, 80 µg/paw). The antinociception was not reversed by opioid and cannabinoid receptor antagonists naloxone, AM 251 and AM 630. The involvement of nitric oxide (NO) was observed by the reversal of H2O2-induced antinociception using the non-selective inhibitor of nitric oxide synthases L-NOarg and by inhibition of iNOS (L-NIL), eNOS (L-NIO) and nNOS (L-NPA). ODQ, a cGMP-forming enzyme selective inhibitor, also reversed the antinociception. The blockers of potassium channels voltage-gated (TEA), ATP-sensitive (glibenclamide), large (paxillin) and small (dequalinium) conductance calcium-activated were able to revert H2O2 antinociception. Our data suggest that H2O2 induced a peripheral antinociception in mice and the NO pathway and potassium channels (voltage-gated, ATP-sensitive, calcium-activated) are involved in this mechanism. However, the role of the opioid and cannabinoid systems was not evidenced.

Potential roles for eNOS and NrF₂ /HO-1 signaling in the ameliorative effect of lixisenatide on diabetes-induced kidney injury in rats and its amplification by ticagrelor co-administration.

Antioxidant and anti-inflammatory effects of lixisenatide (LX) and ticagrelor (TC) have been previously identified in type 2 diabetes mellitus (T2DM). Diabetic nephropathy is one of the major complications of T2DM. In the current study, we examined the potential protective effects of LX and TC on experimentally induced diabetic nephropathy in T2DM rats and their possible molecular mechanisms. To examine this possibility, rats were fed a high-fat diet (HFD) for 12 weeks, followed by a single injection of 35 mg/kg streptozotocin (STZ) to induce T2DM. 10 μg/kg LX and 25 mg/kg TC were given alone or in combination to T2DM rats for 4 weeks. The kidney examination of T2DM rats showed clear deterioration. T2DM rats exhibited significantly higher body weight, blood glucose, hemostatic model assessment for insulin resistance (HOMA-IR), blood urea nitrogen (BUN), serum creatinine, kidney reactive oxygen species (ROS), nuclear factor-κ B (NF-κ B), and transforming growth factor-β (TGF-β ), and significantly lower serum insulin, urine creatinine, creatinine clearance (CRCL), kidney superoxide dismutase (SOD), glutathione reduced (GSH), nuclear factor erythroid 2 (NrF₂ ), heme oxygenase-1 (HO-1), and endothelial nitric oxide synthase (eNOS) when compared to control rats. Single treatment with LX or TC showed obvious ameliorative effects on kidney complications in T2DM rats, with more ameliorative effects with the combined administration of both drugs. Conclusion: Our investigation found that both LX and TC could significantly ameliorate the development of diabetic nephropathy via stimulating NrF₂ /HO-1 antioxidant pathway in addition to increasing eNOS and decreasing NF-κ B renal tissue concentrations, and these effects were markedly augmented by their combined administration.

Ziziphus jujuba (Jujube) in Metabolic Syndrome: From Traditional Medicine to Scientific Validation.

This review evaluates the therapeutic potential of Ziziphus jujuba and its main components in managing complications of metabolic syndrome, including diabetes, dyslipidemia, obesity, and hypertension. The reviewed studies provide evidence supporting the use of Z. jujuba and its main components (lupeol and betulinic acid) as natural treatments for complications of metabolic syndrome. These substances enhance glucose uptake through the activation of signaling pathways such as phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), reduce hepatic glucose synthesis, and increase glucose uptake by adipocytes and skeletal muscle cells. They also improve insulin sensitivity by modulating AMP-activated protein kinase (AMPK) activity and regulating insulin signaling proteins and glucose transporters. In the field of dyslipidemia, they inhibit triglyceride synthesis, lipid accumulation, and adipogenic enzymes, while influencing key signaling pathways involved in adipogenesis. Z. jujuba and its constituents demonstrate anti-adipogenic effects, inhibiting lipid accumulation and modulating adipogenic enzymes and transcription factors. They also exhibit positive effects on endothelial function and vascular health by enhancing endothelial nitric oxide synthase (eNOS) expression, NO production, and antioxidant enzyme activity. Z. jujuba, lupeol, and betulinic acid hold promise as natural treatments for complications of metabolic syndrome. They improve glucose metabolism, insulin sensitivity, and lipid profiles while exerting anti-adipogenic effects and enhancing endothelial function. However, further research is needed to elucidate the mechanisms and confirm their efficacy in clinical trials. These natural compounds offer potential as alternative therapies for metabolic disorders and contribute to the growing body of evidence supporting the use of natural medicines in their management.

Tumor NOS2 and COX2 Spatial Juxtaposition with CD8+ T Cells Promote Metastatic and Cancer Stem Cell Niches that Lead to Poor Outcome in ER- Breast Cancer.

This work identifies CD8-NOS2+COX2+ and CD8-NOS2-COX2+ unique cellular neighborhoods that drive the tumor immune spatial architecture of CD8+ T cells predictive of clinical outcome and can be targeted with clinically available NOS inhibitors and NSAIDs.

Knockout of Sirtuin 3 in endothelial cells impairs endothelial-dependent relaxation and myogenic response in mice.

Sirtuin 3 has been shown to regulate endothelial function and coronary flow reserve in mice. Knockout of SIRT3 reduced endothelial nitric oxide synthase expression in the mouse hearts. In this study, we investigate whether endothelial SIRT3 regulates vascular function and myogenic responses in distal intramural branches of the left anterior descending coronary artery (CA) and middle cerebral artery (MCA) of mice. Both male and female endothelial SIRT3 knockout (SIRT3ECKO) mice and control SIRT3LoxP mice were used and CA and MCA were dissected and mounted in a myograph system. The myogenic response was evaluated by measuring changes in inner diameter in response to 20 mmHg stepwise increases in intraluminal pressure in PSS (active diameter) and Ca2+-free PSS (passive diameter). Acetylcholine (Ach)-induced endothelial-dependent relaxation (EDR) and sodium nitroprusside (SNP)-induced endothelial-independent relaxation (EIR) were examined. Our results showed that the myogenic responses were significantly impaired in both the CA and MCA of SIRT3ECKO mice. Furthermore, female mice had worsened myogenic response in MCA. In CA, EDR was abolished in both male and female SIRT3ECKO mice. Intriguingly, EIR was only reduced in the female mice. In MCA, EDR was reduced in male SIRT3ECKO mice, whereas EIR was decreased in both male and female mice. Female SIRT3ECKO mice had profound dysfunction in CA, whereas male mice exhibited more dysfunction in MCA. These data revealed a sex and organ-specific role of endothelial SIRT3 in vascular function and myogenic responses. Our study suggests that endothelial SIRT3 is necessary for maintaining vascular function and blood flow autoregulation.

Glucose and pH dual-responsive hydrogels with antibacterial, reactive oxygen species scavenging, and angiogenesis properties for promoting the healing of infected diabetic foot ulcers

The healing process of diabetic foot ulcers is challenging due to the presence of a complex and severe inflammatory microenvironment, characterized by hyperglycemia, low pH, susceptibility to infection, vascular dysfunction, and over-expression of reactive oxygen species (ROS), which can potentially lead to amputation or even mortality. Herein, a glucose and pH dual-responsive hydrogel was designed and prepared by crosslinking phenylboronic acid-grafted quaternary chitosan (QF, 4 wt%) with dopamine-grafted oxidized hyaluronic acid (OD, 5 wt%) through phenylboronation, schiff-base reaction, and other techniques. The multifunctional QO/@PV@AB7 hydrogel was prepared by incorporating pravastatin-loaded chitosan nanoparticles (CSNPs@PV, 2 mg/mL) and antimicrobial peptide AMP-AB7 loaded silica nanoparticles (SiO2NPs@AB7, 0.5 mg/mL). The results demonstrate that the QO/@PV@AB7 hydrogel exhibits good responsiveness to acidic conditions and high glucose levels, while effectively scavenging various types of ROS. Moreover, it exerted protective effects against oxidative stress on cells, enhanced HUVECs viability, and promoted angiogenesis. Notably, the QO/@PV@AB7 hydrogel displayed potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli. Additionally, in an MRSA-infected rat model of diabetic foot wounds, administration of the QO/@PV@AB7 hydrogel led to increased secretion of pro-angiogenic factors such as vascular endothelial nitric oxide synthase (eNOS), vascular endothelial-generating factor (VEGF), and endothelial cell adhesion molecule (CD31). Furthermore, the hydrogel significantly reduced the levels of inflammatory factors such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), while simultaneously increasing the levels of anti-inflammatory cytokines such as interleukin-10 (IL-10). The findings suggest that multifunctional hydrogels incorporating PV@CSNPs and SiO2NPs@AB7 demonstrate promising potential as a therapeutic approach for the treatment of diabetic foot. Statement of SignificanceHere, a glucose and pH dual-responsive QO/@PV@AB7 hydrogel with antimicrobial and angiogenesis-promoting properties was developed for the treatment of infected wounds in diabetic feet. Our findings demonstrate that the proposed hydrogel exhibits good responsiveness, effectively scavenges various types of reactive oxygen species (DPPH, O2-, -OH, and ABTS+), provides protection against oxidative stress, enhances HUVECs cell viability, and promotes angiogenesis. Notably, it also demonstrates potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) and E. coli. Additionally, in vivo experiments demonstrated that the hydrogel exhibited accelerated wound healing in MRSA-infected diabetic foot ulcers, with a reduction of four days compared to the control group.

An in vitro cell model for exploring inflammatory and amyloidogenic events in alkaptonuria.

Alkaptonuria (AKU) is a progressive systemic inherited metabolic disorder primarily affecting the osteoarticular system, characterized by the degeneration of cartilage induced by ochronosis, ultimately leading to early osteoarthritis (OA). However, investigating AKU pathology in human chondrocytes, which is crucial for understanding the disease, encounters challenges due to limited availability and donor variability. To overcome this obstacle, an in vitro model has been established using homogentisic acid (HGA) to simulate AKU conditions. This model employed immortalized C20/A4 human chondrocytes and serves as a dependable platform for studying AKU pathogenesis. Significantly, the model demonstrates the accumulation of ochronotic pigment in HGA-treated cells, consistent with findings from previous studies. Furthermore, investigations into inflammatory processes during HGA exposure revealed notable oxidative stress, as indicated by elevated levels of reactive oxygen species and lipid peroxidation. Additionally, the model demonstrated HGA-induced inflammatory responses, evidenced by increased production of nitric oxide, overexpression of inducible nitric oxide synthase, and cyclooxygenase-2. These findings underscore the model's utility in studying inflammation associated with AKU. Moreover, analysis of serum amyloid A and serum amyloid P proteins revealed a potential interaction, corroborating evidence of amyloid fibril formation. This hypothesis was further supported by Congo red staining, which showed fibril formation exclusively in HGA-treated cells. Overall, the C20/A4 cell model provided valuable insights into AKU pathogenesis, emphasizing its potential for facilitating drug development and therapeutic interventions.

Protective Responses of Green Yuja Peel Extracts to Lipopolysaccharide-Induced Inflammation and Reactive Oxygen Species Production in RAW264.7 Cells.

This study assessed the anti-inflammatory and antioxidant effects of green yuja peel hot water extract (GYW) and ethanol extract (GYE) on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. GYW and GYE (50, 100, and 200 μg/mL) significantly reduced the LPS-induced production of nitric oxide (NO), interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and reactive oxygen species in a concentration-dependent manner, without cytotoxicity. Compared with control cells, GYW and GYE significantly downregulated the protein levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) and the gene expression of iNOS, COX-2, TNF-α, and IL-6. Conversely, they upregulated the gene expression of IL-10. Moreover, GYW and GYE significantly suppressed NF-κB p65 and IκB-α phosphorylation and increased the protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target heme oxygenase-1 (HO-1) compared with control cells. These results suggest that GYW and GYE exhibit anti-inflammatory and antioxidative properties by downregulating the NF-κB signaling pathway and upregulating the Nrf2/HO-1 system in LPS-activated macrophages.

Hepatoprotective effects of vildagliptin mitigates lung biochemical and histopathological changes in experimental hepatopulmonary syndrome model in rat

Hepatopulmonary syndrome (HPS) is a liver disease-induced pulmonary complication manifested with arterial hypoxemia. Hepatic cholestasis, encountered in several clinical situations, leads to biliary cirrhosis and HPS, both of which are best reproduced by rat common bile duct ligation (CBDL). Experience from liver transplantation suggests hepatoprotective-based therapy would be most effective in HPS treatment Dipeptidyl peptidase-4 (DPP-4) enzyme is involved in different pathogenic mechanisms of liver diseases. Vildagliptin (Vild) is a DPP-4 inhibitor which possesses favorable anti-inflammatory, anti-oxidant and anti-fibrotic effects. The present work explored hepatoprotective mechanisms of Vild and their participation in its prophylactic effectiveness in HPS induced by CBDL in rats. Male Wistar rats weighing 220–280 g were allocated into 4 groups: normal control, sham, CBDL and CBDL + Vild groups. i.p. saline was administered to the first 3 groups and i.p. Vild (10 mg/kg/day) was given to the fourth group for 6 weeks starting 2 week before CBDL. CBDL produced liver fibrosis, arterial hypoxemia and decreased survivability of rats. It altered liver functions and induced oxidative stress, pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6)], vasodilatory molecules [endothelin-1 (ET-1), and inducible and endothelial nitric oxide synthases] and angiogenesis-associated protein [vascular endothelial growth factor-A (VEGF-A)] in liver and lung. Vild ameliorated liver fibrosis, and improved hypoxemia and survivability of CBDL rats and reversed these biochemical alterations. Prophylactic Vild administration attenuated CBDL-induced HPS in rats via direct hepatoprotective effects in the form of anti-oxidant, anti-inflammatory, anti-angiogenic and anti-fibrotic effects beside inhibition of pathological intrahepatic vasodilatation.

Evaluation of anti-hypertensive activity of Quercus leucotrichophora A. camus methanolic extract on DOCA-salt induced hypertensive rats

Quercus leucotrichophora A. camus, commonly known as Banj oak or Ban tree, belongs to the Fagaceae family and is abundantly found in the regions of Shimla, Kullu-Manali, and upper Mandi in Himachal Pradesh. This study explores the medicinal properties of plant seeds, known for their antioxidant and diuretic activity, traditionally utilized in the treatment of hypertension and hypolipidemic, hepatoprotective conditions. PurposeTo investigate the antihypertensive effect of methanolic extract of Quercus leucotrichophora A. camus seeds in DOCA sat induced rats. Material and methodsGround seeds of Quercus leucotrichophora A. camus were stored in an airtight container. A total of 100 gs of dried seed powder were subjected to extraction using 250 ml of methanol and a Soxhlet extractor maintained at 60–65 °C for five hours. The resulting dried extract (5 gs) was stored in an airtight container in a refrigerator at low temperature and administered by rats to test its antihypertensive impact. The assessment of obtained extract impact on hypertension induced by DOCA-salt was conducted through blood pressure measurement and biochemical analysis. ResultsOur study revealed that the methanolic extract of Quercus leucotrichophora A. camus seeds exerted blood pressure-lowering effects, associated with an increase in serum Nitric Oxide (NO) levels. The attenuation of hypertension by extract was further linked to the normalization of serum Na+ and K+concentrations, indicating an improvement in electrolyte imbalance. Additionally, the antioxidant properties of Quercus leucotrichophora A. camus were evident through increased activities of Glutathione (GSH), Glutathione Peroxidase (GHPx), Superoxide Dismutase (SOD), and decrease activity of Thiobarbituric acid reactive substances (TBARS). ConclusionThe findings of our investigation suggest that the antihypertensive action of Quercus leucotrichophora A. camus is correlated with enhanced endothelial nitric oxide synthase (eNOS) activation and an augmented antioxidant defense system. This sheds light on the potential therapeutic benefits of plant under investigation in managing hypertension, emphasizing its role in promoting cardiovascular health. Further research is warranted to elucidate the underlying mechanisms and to explore the full pharmacological potential of Quercus leucotrichophora A. camus in the field of cardiovascular medicine.

Anti-inflammatory effects of 1,7-dihydroxy-3,4-dimethoxyxanthone through inhibition of M1-phenotype macrophages via arginine/mitochondrial axis.

It is known that 1,7-dihydroxy-3,4-dimethoxyxanthone (XAN), derived from Securidaca inappendiculata Hassk., exhibits anti-inflammatory and analgesic activities and inhibits M1 polarization of macrophages. However, its ability to alleviate inflammation induced by pro-inflammatory cytokines in THP-1 cells and its anti-inflammatory mechanisms remain unclear. THP-1 cells were treated with phorbol 12-myristate-13-acetate to differentiate and divided into three groups. They were stimulated with lipopolysaccharide (LPS) and interferon-γ (IFN-γ). The toxicity of XAN was assessed using Cell Counting Kit-8, and the expression of various genes and proteins was analyzed using real-time quantitative polymerase chain reaction, flow cytometry, and western blotting. Transmission electron microscopy was used to observe changes in mitochondrial structure. XAN at concentrations ≤ 10µg/mL did not affect THP-1 cell viability and reduced the mRNA expression of pro-inflammatory factors, including interleukin (IL)-1β, inducible nitric oxide synthase (iNOS), NOD-like receptor thermal protein domain protein 3 (NLRP3), and tumor necrosis factor-α (TNF-α). XAN also increased the levels of anti-inflammatory factors, including chemokine ligand 22, mannose receptor (CD206), IL-10, peroxisome proliferator-activated receptor-γ, and transglutaminase 2. Additionally, XAN downregulated the expression of inflammation-related proteins iNOS, NLRP3, and IL-1β; significantly increased the expression of arginase 1, ornithine decarboxylase, and arginine metabolism-related proteins and genes; inhibited mitochondrial damage; and reduced reactive oxygen species (ROS) generation. XAN enhanced the arginine metabolism pathway, prevented mitochondrial damage, reduced ROS levels, and provided an effective defensive response against LPS/IFN-γ-induced inflammation.

Catechin reduces liver inflammation by regulating Kupffer cell activation in rats

The liver is a defense against infections due to its strategic location between the gastrointestinal and systemic circulations. In dogs and cats, infectious hepatitis encompasses a range of contagious diseases affecting the liver either directly or as part of a broader systemic infection, including bacterial, mycobacterial, viral, fungal, protozoal, parasitic, and rickettsial diseases. Catechins possess well-recognized natural antioxidant properties. This study investigated their therapeutic potential for applications in hepatology, evaluating whether catechins reduce hepatic inflammation in rats repeatedly exposed to carbon tetrachloride (CCl4). Sprague-Dawley rats were given catechin 50 (C50) or 100 (C100) mg/kg body weight orally daily for 3 days. This treatment was given with or without concurrent intraperitoneal injections of CCl4. Phosphate-buffered saline served as the vehicle control, while silymarin administered at 100 mg/kg was used as the positive control.Gross examination revealed significant enlargement, edema, and darker tissue in CCl4-induced livers treated with vehicle. Additionally, spotty discoloration was observed on the surface. Kupffer cell activation suppressed the expression of inflammatory mediators, including inducible nitric oxide synthase (iNOS), in groups co-treated with catechin and CCl4; this effect was reversed when catalase replaced catechin in CCl4-injured rats. Catechin alleviates hepatic inflammation in rats repeatedly exposed to CCl4; it also modulates the activation of Kupffer cells and monocytes. These results should lead to new treatments for liver inflammation in veterinary practice.

Agomelatine-loaded nanostructured lipid carriers alleviate neuropathic pain in rats by Nrf2/HO-1 signalling pathway.

Neuropathic pain arises from impairments or malfunctions within the nervous system, resulting in atypical transmission and interpretation of pain signals. In the present study, we examined the neuroprotective effects of agomelatine (AGM) and agomelatine-loaded nanostructured lipid carriers (AGM-NLCs) in neuropathic animal models induced by chronic constriction injury (CCI) of the sciatic nerve. Male Sprague Dawley rats were divided into seven experimental groups to compare the effects of AGM and AGM-NLCs, which were administered at 20 mg/kg for 14 consecutive days after CCI. Our finding demonstrated that CCI triggered the onset of analgesia in these animals, corroborated by mechanical allodynia and thermal hyperalgesia. Furthermore, CCI induced an elevation in inflammatory mediators such as interleukin (IL)-1β and inducible nitric oxide synthase (iNOS), and downregulated heme oxygenase-1 (HO-1) and nuclear factor E2-related factor (Nrf2). Treatment with AGM and AGM-NLCs reversed inflammatory cascades and elevated antioxidant enzyme levels, leading to a reduction in paw withdrawal latency and threshold in rats. To further investigate the effect of AGM and AGM-NLCs, all-trans retinoic acid (ATRA) was administered, which antagonizes Nrf2. ATRA substantially downregulated Nrf2 expression and exacerbated thermal hyperalgesia, whereas Nrf2 and HO-1 expressions were significantly upregulated after AGM-NLCs administration. Overall, the results demonstrated that AGM-NLCs offer promising antinociceptive and anti-inflammatory properties in alleviating neuropathic pain symptoms, which can be attributed to improved drug delivery and therapeutic outcomes compared with AGM alone.

Phytochemical Analysis and Evaluation of Antioxidant, Antidiabetic, and Anti-inflammatory Properties of Aegle marmelos and Its Validation in an In-Vitro Cell Model.

Persistent hyperglycemia significantly increases oxidative stress and inflammation resulting in multiple cellular and molecular alterations which further exacerbate the diabetes associated complications.Aegle marmelos (L.) Corrêais a medicinal plant used in the Indian system of medicine for treating various disorders including diabetes. However, studies on phytoconstituents and their pharmacological activity of this plant are limited. Therefore, we aimed to determine the phytochemical components, evaluate the antidiabetic activity, anti-inflammatory activity, and antioxidant activity ofA. marmelosleaf extract, and validate its mechanistic effects in an in vitro cell model. The qualitative and quantitative analysis of the different phytoconstituents in the extract was determined using standardized protocols. The antioxidant activity of the extract was evaluated by 2,2-di-phenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay and ferric reducing antioxidant power (FRAP) assay. The antidiabetic activity of the extract was evaluated by α-amylase inhibition and α-glucosidase inhibition assay. The anti-inflammatory activity was studied using an albumin denaturation assay. In addition, the pharmacological effect(s) of leaf extract was checked in the normal rat kidney fibroblast cells (NRK-49F) under high glucose conditions. Intracellular reactive oxygen species (ROS) generation was measured by fluorometry using fluorescence probe 2',7'-dichlorodihydrofluorescin diacetate (DCF-DA). mRNA expression of inflammatory markers including inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-α) was studied using real-time quantitative polymerase chain reaction (RT-qPCR). Cell migration was studied using cell scratch assay. Statistical analysis was performed using GraphPad Prism version 8.0. The phytochemical analysis ofA. marmelosleaf extract revealed the presence of alkaloids, phenols, flavonoids, and saponins. The extract showed higher antioxidant activity in the DPPH (IC50=258.21 µg/mL) and FRAP assay (IC50=293.83 µg/mL). The extract exhibited prominent antidiabetic activity by inhibiting enzymes α-Amylase (IC50=73.2 µg/mL) and α-glucosidase (IC50=43.9 µg/mL). In addition, the extract showed effective anti-inflammatory activity by significantly inhibiting the denaturation of egg albumin (IC50=102.8 µg/mL). Further, the leaf extract significantly decreased the high glucose-induced ROS generation as well as inflammatory markers in rat fibroblast cell lines in a dose-dependent manner. Additionally, high glucose-induced cell migration as the measure of cell injury was effectively reduced by the extract treatment. A. marmelosleafextract was quantified to possess a substantial amount of important phytoconstituents that have promising pharmacological properties. Besides showing antidiabetic activity, the extract significantly combats the high glucose-induced ROS generation, inflammatory markers expressions, and cell migration. Further, in-depth studies and clinical trials are warranted so as to position these traditional remedies for the treatment of metabolic disorders.

Genetic polymorphisms associated with preeclampsia risk in Nigerian women

BackgroundPreeclampsia, a complex hypertensive disorder unique to pregnancy, significantly impacts maternal and fetal health worldwide, with a prevalence of 2–8%. This condition results from a complex interplay of genetic, environmental, and immunological factors.Aim and objectivesThis study aims to investigate the genetic predispositions to preeclampsia, focusing on specific gene polymorphisms among pregnant women at Central Hospital Auchi, Nigeria.Materials and methodsWe examined the endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), angiotensin-converting enzyme (ACE), and tumor necrosis factor-alpha (TNF-α) genes in 200 pregnant women, equally divided between preeclamptic patients and normotensive controls.ResultsThe eNOS G894T polymorphism was significantly associated with preeclampsia, with the T allele nearly doubling the risk. The VEGF C936T polymorphism's T allele also indicated a higher risk. The D allele in the ACE gene's insertion/deletion (I/D) polymorphism significantly increased the risk, as did the A allele in the TNF-α G308A polymorphism.ConclusionsThese findings highlight the importance of genetic factors in preeclampsia and suggest that genetic screening could improve risk stratification and early detection. Future research should integrate genetic, epigenetic, and environmental data to understand preeclampsia's multifaceted nature and develop targeted therapies. This study underscores the potential of personalized medicine in managing and reducing the risks associated with preeclampsia.

Establishment of a workflow for high-throughput identification of anti-inflammatory peptides from sea cucumbers

Developing an effective workflow for screening anti-inflammatory peptides is crucial for discovering novel food-derived anti-inflammatory peptides and optimizing the screening and identification process of bioactive peptides. Virtual screening identified three major yolk proteins as target precursor proteins for anti-inflammatory peptides in sea cucumbers. A portfolio of 170 peptides was identified from hydrolysates after 9 h of alcalase treatment by combining antioxidant activity determination and peptidomics analysis. Among these, 12 high-confidence anti-inflammatory peptides were identified through virtual screening. Three of these peptides were shown to effectively inhibit the production of NO and the release of pro-inflammatory cytokines in RAW264.7 cells. Molecular docking demonstrated that these three peptides exerted their anti-inflammatory effects primarily by binding to the active sites of cyclooxygenase-2 and inducible nitric oxide synthase through hydrophobic interactions. This study provided a reference workflow for screening anti-inflammatory peptides, facilitating the discovery of novel anti-inflammatory peptides and the high-value utilization of sea cucumber cooking liquid.