Physiology and pathophysiology of cyclooxygenase-2 and prostaglandin E2 in the kidney

Therapeutic potential and pharmacological mechanism of visnagin

Visnagin is a furanochromone and one of the most important compound in the Ammi visnaga (L.) Lam (a synonym of Visnaga daucoides Gaertn.) plant, which is used to cure various ailments. Many investigations into the bioactive properties of visnagin have been studied to date. The literature on visnagin demonstrates its biological properties, including anti-inflammatory, anti-diabetic, and beneficial effects in cardiovascular and renal diseases. Moreover, visnagin improves sperm quality parameters, stimulates steroidogenesis, and increases serum gonadotropins and testosterone levels, while decreasing pro-inflammatory cytokines, oxidative damage, genomic instability, and it modulates apoptosis. Thus, visnagin has emerged as an exciting lead for further research, owing to its potential in various unmet clinical needs. The current review summarized its basic structure, pharmacokinetics, and pharmacological effects, focusing on its mechanisms of action. The review will help to understand the potential of visnagin as an alternative treatment strategy for several diseases and provide insight into research topics that need further exploration for visnagin's safe clinical use. Please cite this article as: Yadav P, Singh SK, Datta S, Verma S, Verma A, Rakshit A, Bali A, Bhatti JS, Khurana A, Navik U. Therapeutic potential and pharmacological mechanism of visnagin. J Integr Med. 2024; Epub ahead of print.

Aquaporins (AQPs) as a marker in the physiology of inflammation and its interaction studies with garcinol

Aquaporins like AQP1, AQP3, and AQP4 are known to be involved in the pathophysiology of inflammation based on earlier reports. This study aimed to evaluate the involvement of Aquaporins as a potential target of inflammation. The study also investigates the efficacy of methanolic extract of Garcinia (GME) and its potent phytocompound (garcinol) against the Aquaporins involved in inflammation. siRNA silencing of AQP3 was carried out in RAW264.7 cells followed by LPS stimulation (1 µg/ml) and assessment of important markers of inflammation including NO, PGE2, TNF-α, IL-6, IL-1β, CCL20, iNOS and COX-2. To assess the anti-inflammatory potential of Garcinia extract and garcinol, cells were stimulated with 1 µg/ml LPS in the absence and presence of increasing concentrations of GME and garcinol. During the experimental period, extract concentrations (115 µg/ml and 230 µg/ml for RAW264.7; 118 µg/ml and 236 µg/ml for THP-1) and garcinol concentrations (6 µM and 12 µM for RAW264.7; 3 µM and 6 µM for THP-1) were selected based on the IC50. The anti-inflammatory effects were assessed by measuring the levels of TNF-α, IL-1β, IL-6, and CCL20 in LPS-stimulated cells. The AQP expression was studied at transcriptional and translational levels using qPCR and Western blot analysis respectively. AQP3 knockdown significantly decreased the NO, PGE2, TNF-α, IL-1β levels along with iNOS and COX-2 mRNA expression. LPS stimulation led to a significant increase in the mRNA and protein level expression AQP1, AQP3, and AQP4 in RAW264.7 cells; and AQP1 and AQP3 in THP-1 cells indicating their role as markers of inflammation. GME and garcinol effectively suppressed the LPS-induced proinflammatory cytokine production in both cell lines. The results indicate that AQP1, AQP3, and AQP4 could play a crucial role as markers of inflammation. Anti-inflammatory agents like Garcinia could potentially decrease the expression of such AQPs, thus inhibiting the inflammatory process.

Design of potential anti-cancer agents as COX-2 inhibitors, using 3D-QSAR modeling, molecular docking, oral bioavailability proprieties, and molecular dynamics simulation

Modeling the structural properties of novel morpholine-bearing 1, 5-diaryl-diazole derivatives as potent COX-2 inhibitor, two proposed models based on CoMFA and CoMSIA were evaluated by external and internal validation methods. Partial least squares analysis produced statistically significant models with Q 2 values of 0.668 and 0.652 for CoMFA and CoMSIA, respectively, and also a significant non-validated correlation coefficient R² with values of 0.882 and 0.878 for CoMFA and CoMSIA, respectively. Both models met the requirements of Golbraikh and Tropsha, which means that both models are consistent with all validation techniques. Analysis of the CoMFA and CoMSIA contribution maps and molecular docking revealed that the R1 substituent has a very significant effect on their biological activity. The most active molecules were evaluated for their thermodynamic stability by performing MD simulations for 100 ns; it was revealed that the designed macromolecular ligand complex with 3LN1 protein exhibits a high degree of structural and conformational stability. Based on these results, we predicted newly designed compounds, which have acceptable oral bioavailability properties and would have high synthetic accessibility.

Anti-inflammatory effects of Mentha pulegium L. extract on human peripheral blood mononuclear cells are mediated by TLR-4 and NF-κB suppression

There is great interest in evaluating the anti-inflammatory properties of new herbal products. Thus, the effects of Mentha pulegium L. extract on gene and protein expressions of pro-inflammatory mediators and transcription factors were determined. The hydro-ethanolic extract of Mentha pulegium L. was obtained and optimal non-cytotoxic concentrations of the extract were determined by MTT assay. Then, three different concentrations of Mentha pulegium L. (10, 30, and 90 μg/mL) were used to pre-treat the lipopolysaccharide (LPS)-stimulated and non-stimulated peripheral blood mononuclear cells (PBMCs) of 10 healthy individuals. Finally, the tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, Toll-like receptor-4 (TLR-4), nuclear factor-kappa B (NF-κB) p65, activator protein-1 (AP-1), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) gene expressions and TNF-α, IL-1β, IL-6, TLR-4, prostaglandin E2 (PGE2), and COX-2 protein levels were measured. MTT results showed that there is no significant difference in cell viability among 10, 20, 40, and 80 μg/mL concentrations of Mentha pulegium L. extract at 24, 48, and 72 h (P > 0.05). The IC50 values were 236.1, 147.0, and 118.0 μg/mL after 24, 48, and 72 h respectively. TNF-α, IL-1β, IL-6, TLR-4, iNOS, and NF-κB p65 mRNA levels in the pre-treated LPS-stimulated PBMCs were concentration-dependently reduced (P < 0.01 for TNF-α, TLR-4, and NF-κB p65; P < 0.05 for IL-1β, IL-6, and iNOS). Also, the protein levels of pro-inflammatory mediators decreased and these differences were significant for TNF-α, IL-1β, and TLR-4 (P < 0.001, P < 0.01, and P < 0.001, respectively). Mentha pulegium L. extract decreased the expression and biosynthesis of pro-inflammatory mediators. These effects are mainly mediated by TLR-4 and NF-κB suppression. Thus, Mentha pulegium L. could be useful in treating or ameliorating chronic inflammatory diseases.

Dual COX-2/15-LOX inhibitors: A new avenue in the prevention of cancer

Dual cyclooxygenase 2/15-lipoxygenase inhibitors constitute a valuable alternative to classical non-steroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 (cyclooxygenase-2) inhibitors for the treatment of inflammatory diseases, as well as preventing the cancer. Indeed, these latter present diverse side effects, which are reduced or absent in dual-acting agents. In this review, COX-2 and 15-LOX (15-lipoxygenase) pathways are first described in order to highlight the therapeutic interest of designing such compounds. Various structural families of dual inhibitors are illustrated. This study discloses various structural families of dual 15-LOX/COX-2 inhibitors, thus pave the way to design potentially-active anticancer agents with balanced dual inhibition of these enzymes.

Neuroendocrine response to diclofenac in healthy subjects: a pilot study

PURPOSE

The precise effects of non-steroidal anti-inflammatory drugs on the neuroendocrine hydro-electrolytic regulation are not precisely understood. The aim of this pilot study was to evaluate, in healthy subjects, the neuroendocrine response of the antidiuretic system to intravenous diclofenac infusion.

METHODS

For this single-blinded, cross-over study, we recruited 12 healthy subjects (50% women). Test sessions were divided into three observation times (pre-test; test; 48 h post-test), which were repeated equally on two different occasions, with the administration of diclofenac (75 mg in saline solution 0.9% 100 cc) on 1 day, or placebo (saline solution 0.9% 100 cc) on another day. The night before the test the subjects were asked to collect a salivary cortisol and cortisone sample, which was repeated on the night of the procedure session. Serial urine and blood samples were collected on the test day (for osmolality, electrolytes, ACTH, cortisol, copeptin, MR-proADM, MR-proANP; the last three represent more stable and analytically reliable molecules than their respective active peptides). Moreover, the subjects were evaluated with the bioimpedance vector analysis (BIVA) before and after the test. Forty-eight hours after the end of the procedure urine sodium, urine potassium, urine osmolality, serum sodium and copeptin were revaluated together with BIVA.

RESULTS

No significant changes in circulating hormone levels were observed; anyway, 48 h after diclofenac, BIVA showed a significant water retention (p < 0.00001), especially in extracellular fluid (ECF) (16.47 ± 1.65 vs 15.67 ± 1.84, p < 0.001). Salivary cortisol and cortisone tended to increase only the night after placebo administration (p = 0.054 cortisol; p = 0.021 cortisone).

CONCLUSION

Diclofenac resulted in an increased ECF at 48 h, but this phenomenon seems to be associated with a greater renal sensibility to the action of vasopressin rather than with an increase in its secretion. Moreover, a partial inhibitory effect on cortisol secretion can be hypothesized.

Effects of phenylbutazone, firocoxib, and dipyrone on the diuretic response to furosemide in horses

BACKGROUND

Treatment with phenylbutazone (nonselective COX inhibitor) decreases the diuretic and natriuretic effects of furosemide by nearly 30% but the effects of COX-2 specific inhibitors (firocoxib) and atypical NSAIDs (dipyrone) are unknown.

HYPOTHESIS

Furosemide-induced diuresis after pretreatment with firocoxib or dipyrone is diminished to a lesser extent than after pretreatment with phenylbutazone.

ANIMALS

Eight healthy mares.

METHODS

Each mare received 4 treatments in a prospective experimental crossover study using a replicated 4 × 4 Latin Square design: furosemide alone (FU), furosemide and phenylbutazone (PB), furosemide and firocoxib (FX), and furosemide and dipyrone (DP). After 24 hours of NSAID treatment at recommended dosages, ureteral catheters were placed for continual urine collection. After a 30-minute baseline collection period, furosemide (1.0 mg/kg, IV) was administered, and urine and blood samples were collected for 4 hours. Data were assessed by repeated measures ANOVA.

RESULTS

Four-hour urine volume was (mean ± SD) ~25% less (P < .001) after pretreatment with all NSAIDs (PB 19.1 ± 2.1 mL/kg, FX 17.7 ± 3.5 mL/kg, DP 19.1 ± 3.9 mL/kg), as compared to FU (23.4 ± 5.1 mL/kg) (P < .001), but there were no differences between PB, FX, or DP. Interindividual variability in furosemide diuresis after pretreatment with different NSAIDs was observed.

CONCLUSIONS AND CLINICAL IMPORTANCE

Though COX-2 selective NSAIDs and dipyrone might have less severe or fever gastrointestinal adverse effects in horses, our data suggest minimal differences in effects on furosemide-induced diuresis, and possibly, risk of nephrotoxicosis.

Obstructive nephropathy and molecular pathophysiology of renal interstitial fibrosis

The kidneys play a key role in maintaining total body homeostasis. The complexity of this task is reflected in the unique architecture of the organ. Ureteral obstruction greatly affects renal physiology by altering hemodynamics, changing glomerular filtration and renal metabolism, and inducing architectural malformations of the kidney parenchyma, most importantly renal fibrosis. Persisting pathological changes lead to chronic kidney disease, which currently affects ∼10% of the global population and is one of the major causes of death worldwide. Studies on the consequences of ureteral obstruction date back to the 1800s. Even today, experimental unilateral ureteral obstruction (UUO) remains the standard model for tubulointerstitial fibrosis. However, the model has certain limitations when it comes to studying tubular injury and repair, as well as a limited potential for human translation. Nevertheless, ureteral obstruction has provided the scientific community with a wealth of knowledge on renal (patho)physiology. With the introduction of advanced omics techniques, the classical UUO model has remained relevant to this day and has been instrumental in understanding renal fibrosis at the molecular, genomic, and cellular levels. This review details key concepts and recent advances in the understanding of obstructive nephropathy, highlighting the pathophysiological hallmarks responsible for the functional and architectural changes induced by ureteral obstruction, with a special emphasis on renal fibrosis.

Mechanisms of mechanical overload-induced skeletal muscle hypertrophy: current understanding and future directions

Mechanisms underlying mechanical overload-induced skeletal muscle hypertrophy have been extensively researched since the landmark report by Morpurgo (1897) of "work-induced hypertrophy" in dogs that were treadmill trained. Much of the preclinical rodent and human resistance training research to date supports that involved mechanisms include enhanced mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling, an expansion in translational capacity through ribosome biogenesis, increased satellite cell abundance and myonuclear accretion, and postexercise elevations in muscle protein synthesis rates. However, several lines of past and emerging evidence suggest that additional mechanisms that feed into or are independent of these processes are also involved. This review first provides a historical account of how mechanistic research into skeletal muscle hypertrophy has progressed. A comprehensive list of mechanisms associated with skeletal muscle hypertrophy is then outlined, and areas of disagreement involving these mechanisms are presented. Finally, future research directions involving many of the discussed mechanisms are proposed.

Soybean (Glycine max) INFOGEST Colonic Digests Attenuated Inflammatory Responses Based on Protein Profiles of Different Varieties

Soybean compounds have been established to modulate inflammation, but less is known about how whole soybean compositions work together after digestion. The objective was to evaluate and compare the anti-inflammatory responses of different soybean varieties under simulated gastrointestinal digestion, with additional consideration of the glycinin:β-conglycinin ratio (GBR). Soybean colonic digests (SCD) inhibited cyclooxygenase (COX)-2 (25-82%), 5-lipoxidase (LOX) (18-35%), and inducible nitric oxide (iNOS) (8-61%). Varieties 88, GN3, and 93 were the most effective inhibitors. SCD (1 mg/mL) of varieties 81 and GN1 significantly (p < 0.05) reduced nitrite production by 44 and 47%, respectively, compared to lipopolysaccharide (LPS)-stimulated macrophages. SCD effectively reduced pro-inflammatory cytokine interleukin (IL)-6 (50 and 80% for 96 and GN1, respectively). Western blot results showed a decrease in the expression of iNOS, p65, and p50. The GBR was in the range of 0.05-1.57. Higher ratio correlated with higher production of IL-1β (r = 0.44) and tumor necrosis factor-alpha (TNF-α, r = 0.56). Inflammatory microarray results showed a significant decrease in expression of markers granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-6 in cells treated with GN1 SCD compared to LPS. The results suggested that SCD exerted its anti-inflammatory potential through nuclear factor kappa B (NF-κΒ) pathway inhibition by decreasing the levels of NF-κB-dependent cytokines and subunits, and inhibition of pro-inflammatory enzyme activity.

Evaluating the inhibitory activity of ferrocenyl Schiff bases derivatives on 5-lipoxygenase: Computational and biological studies

In the search for new 5-LOX inhibitors, two ferrocenyl Schiff base complexes functionalized with catechol ((ƞ5-(E)-C5H4-NCH-3,4-benzodiol)Fe(ƞ5-C5H5) (3a)) and vanillin ((ƞ5-(E)-C5H4-NCH-3-methoxy-4-phenol)Fe(ƞ5-C5H5) (3b)) were obtained. Complexes 3a and 3b were biologically evaluated as 5-LOX inhibitors showed potent inhibition compared to their organic analogs (2a and 2b) and known commercial inhibitors, with IC50 = 0.17 ± 0.05 μM for (3a) and 0.73 ± 0.06 μM for (3b) demonstrated a highly inhibitory and potent effect against 5-LOX due to the incorporation of the ferrocenyl fragment. Molecular dynamic studies showed a preferential orientation of the ferrocenyl fragment toward the non-heme iron of 5-LOX, which, together with electrochemical and in-vitro studies, allowed us to propose a competitive redox deactivation mechanism mediated by water, where Fe(III)-enzyme can be reduced by the ferrocenyl fragment. An Epa/IC50 relationship was observed, and the stability of the Schiff bases was evaluated by SWV in the biological medium, observing that the hydrolysis does not affect the high potency of the complexes, making them interesting alternatives for pharmacological applications.

Chronic Inflammation's Transformation to Cancer: A Nanotherapeutic Paradigm

The body's normal immune response against any invading pathogen that causes infection in the body results in inflammation. The sudden transformation in inflammation leads to the rise of inflammatory diseases such as chronic inflammatory bowel disease, autoimmune disorders, and colorectal cancer (different types of cancer develop at the site of chronic infection and inflammation). Inflammation results in two ways: short-term inflammation i.e., non-specific, involves the action of various immune cells; the other results in long-term reactions lasting for months or years. It is specific and causes angiogenesis, fibrosis, tissue destruction, and cancer progression at the site of inflammation. Cancer progression relies on the interaction between the host microenvironment and tumor cells along with the inflammatory responses, fibroblast, and vascular cells. The two pathways that have been identified connecting inflammation and cancer are the extrinsic and intrinsic pathways. Both have their own specific role in linking inflammation to cancer, involving various transcription factors such as Nuclear factor kappa B, Activator of transcription, Single transducer, and Hypoxia-inducible factor, which in turn regulates the inflammatory responses via Soluble mediators cytokines (such as Interleukin-6, Hematopoietin-1/Erythropoietin, and tumor necrosis factor), chemokines (such as Cyclooxygenase-2, C-X-C Motif chemokines ligand-8, and IL-8), inflammatory cells, cellular components (such as suppressor cells derived from myeloid, tumor-associated macrophage, and acidophils), and promotes tumorigenesis. The treatment of these chronic inflammatory diseases is challenging and needs early detection and diagnosis. Nanotechnology is a booming field nowadays for its rapid action and easy penetration inside the infected destined cells. Nanoparticles are widely classified into different categories based on their different factors and properties such as size, shape, cytotoxicity, and others. Nanoparticles emerged as excellent with highly progressive medical inventions to cure diseases such as cancer, inflammatory diseases, and others. Nanoparticles have shown higher binding capacity with the biomolecules in inflammation reduction and lowers the oxidative stress inside tissue/cells. In this review, we have overall discussed inflammatory pathways that link inflammation to cancer, major inflammatory diseases, and the potent action of nanoparticles in chronic inflammation-related diseases.

Synthesis, Characterization and Biological Investigation of the Platinum(IV) Tolfenamato Prodrug–Resolving Cisplatin-Resistance in Ovarian Carcinoma Cell Lines

The research on the anticancer potential of platinum(IV) complexes represents one strategy to circumvent the deficits of approved platinum(II) drugs. Regarding the role of inflammation during carcinogenesis, the effects of non-steroidal anti-inflammatory drug (NSAID) ligands on the cytotoxicity of platinum(IV) complexes is of special interest. The synthesis of cisplatin- and oxaliplatin-based platinum(IV) complexes with four different NSAID ligands is presented in this work. Nine platinum(IV) complexes were synthesized and characterized by use of nuclear magnetic resonance (NMR) spectroscopy (1H, 13C, 195Pt, 19F), high-resolution mass spectrometry, and elemental analysis. The cytotoxic activity of eight compounds was evaluated for two isogenic pairs of cisplatin-sensitive and -resistant ovarian carcinoma cell lines. Platinum(IV) fenamato complexes with a cisplatin core showed especially high in vitro cytotoxicity against the tested cell lines. The most promising complex, 7, was further analyzed for its stability in different buffer solutions and behavior in cell cycle and cell death experiments. Compound 7 induces a strong cytostatic effect and cell line-dependent early apoptotic or late necrotic cell death processes. Gene expression analysis suggests that compound 7 acts through a stress-response pathway integrating p21, CHOP, and ATF3.

The delayed effects of acute radiation exposure (DEARE): characteristics, mechanisms, animal models, and promising medical countermeasures

PURPOSE

Terrorist use of nuclear weapons and radiation accidents put the human population at risk for exposure to life-threatening levels of radiation. Victims of lethal radiation exposure face potentially lethal acute injury, while survivors of the acute phase are plagued with chronic debilitating multi-organ injuries for years after exposure. Developing effective medical countermeasures (MCM) for the treatment of radiation exposure is an urgent need that relies heavily on studies conducted in reliable and well-characterized animal models according to the FDA Animal Rule. Although relevant animal models have been developed in several species and four MCM for treatment of the acute radiation syndrome are now FDA-approved, animal models for the delayed effects of acute radiation exposure (DEARE) have only recently been developed, and there are no licensed MCM for DEARE. Herein, we provide a review of the DEARE including key characteristics of the DEARE gleaned from human data as well as animal, mechanisms common to multi-organ DEARE, small and large animal models used to study the DEARE, and promising new or repurposed MCM under development for alleviation of the DEARE.

CONCLUSIONS

Intensification of research efforts and support focused on better understanding of mechanisms and natural history of DEARE are urgently needed. Such knowledge provides the necessary first steps toward the design and development of MCM that effectively alleviate the life-debilitating consequences of the DEARE for the benefit of humankind worldwide.

Exploring the anti-inflammatory potential of Colocasia esculenta root extract in in-vitro and in-vivo models of inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Colocasia esculenta (CE) (L.) Schott is an annual herbaceous tropical plant from the family of Araceae which has been traditionally used for the healing of various ailments such as asthma, arthritis, internal hemorrhage, diarrhea, and neurological disorders. The plant is reported to have potential anti-microbial, anti-fungal, antimetastatic, anti-hepatotoxic, and anti-lipid peroxidative activities.

AIM OF THE STUDY

The present study is designed to explore the potential anti-inflammatory property of Colocasia esculenta methanolic root extract (CEMRE) on carrageenan-induced rat paw edema and lipopolysaccharide (LPS) stimulated RAW264.7 cells.

MATERIALS AND METHODS

Carrageenan-induced rat paw edema model was used to investigate the in vivo anti-inflammatory action of CEMRE. Adult male Wistar rats (180-220 g; n = 6) were pre-treated with CEMRE (100, 200, and 400 mg/kg BW) orally before 1 h of injection of 1% carrageenan. Indomethacin (10 mg/kg BW) was given orally as the standard drug. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), nitric oxide (NO), prostaglandinE2 (PGE2), and cytokines levels were measured. Liquid chromatography-mass spectrometry (LC-MS) was done to identify the phytoconstituents present in CEMRE. The inhibitory activity of CEMRE was investigated against cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in in vitro assessment of LPS-stimulated RAW264.7 cells. The RAW 264.7 cells were pre-treated with Indomethacin (5 μM and 10 μM) and CEMRE (17 μg/ml and 34 μg/ml) followed by induction of LPS (1 μg/ml) for 24 h. Docking analyses were also performed to explore the interaction of important phytoconstituents (Sinapic acid, Acetylsalicylic acid, L-fucose, Salicylic acid, Quinic acid, Zingerone, and Gingerol) of CEMRE with COX-2 and iNOS.

RESULTS

Pre-treatment with CEMRE (400 mg/kg) could inhibit the paw inflammation significantly which was elevated due to carrageenan induction. The inhibition is comparable to that of the standard drug Indomethacin. The concentration of serum AST, ALT, ALP, NO, PGE2 and cytokines were also considerably lowered in the CEMRE-treated group as compared to the carrageenan-induced group. CEMRE (34 μg/ml) inhibited the LPS-stimulated relative expression of mRNA of COX-2 and iNOS and significantly reduced the expression of nitric oxide and prostaglandin E2. Docking analyses revealed promising interaction with low binding energies between Sinapic acid with both the target proteins COX-2 and iNOS.

CONCLUSION

Collectively, our results suggested that CEMRE exhibited effective anti-inflammatory actions on carrageenan-induced rat paw edema and LPS-treated RAW 264.7 cells by reducing the in vivo paw edema inhibition, inhibiting the serum NO, PGE2, cytokines and also reduced the in vitro production of NO, PGE2 along with expressions of mRNA COX-2 and iNOS. Molecular docking demonstrated good binding affinities among the target proteins and ligand Sinapic acid. Thus the bioactive compound from CE need to be isolated and purified.

Vaptans or voluntary increased hydration to protect the kidney: how do they compare?

The adverse effects of vasopressin (AVP) in diverse forms of chronic kidney disease have been well described. They depend on the antidiuretic action of AVP mediated by V2 receptors (V2R). Tolvaptan, a selective V2R antagonist, is now largely used for the treatment of patients with autosomal dominant polycystic kidney disease. Another way to reduce the adverse effects of AVP is to reduce endogenous AVP secretion by a voluntary increase in fluid intake. These two approaches differ in several ways, including the level of thirst and AVP. With voluntary increased drinking, plasma osmolality will decline and so will AVP secretion. Thus, not only will V2R-mediated effects be reduced, but also those mediated by V1a and V1b receptors (V1aR and V1bR). In contrast, selective V2R antagonism will induce a loss of fluid that will stimulate AVP secretion and thus increase AVP's influence on V1a and V1b receptors. V1aR is expressed in the luminal side of the collecting duct (CD) and in inner medullary interstitial cells, and their activation induces the production of prostaglandins, mostly prostaglandin E2 (PGE2). Intrarenal PGE2 has been shown to reduce sodium and water reabsorption in the CD and increase blood flow in the renal medulla, both effects contributing to increase sodium and water excretion and reduce urine-concentrating activity. Conversely, non-steroidal anti-inflammatory drugs have been shown to induce significant water and sodium retention and potentiate the antidiuretic effects of AVP. Thus, during V2R antagonism, V1aR-mediated actions may be responsible for part of the diuresis observed with this drug. These V1aR-dependent effects do not take place with a voluntary increase in fluid intake. In summary, while both strategies may have beneficial effects, the information reviewed here leads us to assume that pharmacological V2R antagonism, with resulting stimulation of V1aR and increased PGE2 production, may provide greater benefit than voluntary high water intake. The influence of tolvaptan on the PGE2 excretion rate and the possibility to use somewhat lower tolvaptan doses than presently prescribed remain to be evaluated.

Potential Role of Non-Steroidal Anti-Inflammatory Drugs in Colorectal Cancer Chemoprevention for Inflammatory Bowel Disease: An Umbrella Review

Inflammatory Bowel Disease (IBD) is a category of autoimmune diseases that targets the destruction of the gastrointestinal system and includes both Crohn's Disease and Ulcerative Colitis (UC). Patients with IBD are at a higher risk of developing colorectal cancer (CRC) throughout their lives due to chronically increased inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) are potential chemopreventative agents that can inhibit the development of CRC in persons without IBD. However, the use of NSAIDs for CRC chemoprevention in IBD patients is further complicated by NSAIDs' induction of damage to the bowel mucosal layer and ulcer formation. There has been a push in new research on chemopreventative properties of certain NSAIDs for IBD. The purpose of this umbrella review is to investigate the potential of low-dose NSAID compounds as chemopreventative agents for patients with IBD. This paper will also suggest future areas of research in the prevention of CRC for patients with IBD.

Exploring the possible mechanism involved in the anti-nociceptive effect of β-sitosterol: modulation of oxidative stress, nitric oxide and IL-6

Β-sitosterol is a phytosterol, documented to possess various activities including protection against inflammation, diabetes and Alzheimer's disease. The current investigation was designed to explore the analgesic potential of β-sitosterol and the possible molecular mechanism involved in the observed effect. β-sitosterol was administered at varying doses of 10, 20, and 40 mg/kg before subjecting the mice to acetic acid and formalin challenges. The number of writhings in acetic acid and the number of flinchings and foot tappings were quantified in the formalin test. For mechanistic studies, substance P (cyclooxygenase-2 (COX-2) stimulator) and L-Nitro arginine methyl ester (L-NAME) (nitric oxide synthetases (NOS) inhibitor) and L-arginine (nitric oxide precursor) were administered before β-sitosterol treatment. β-sitosterol (10, 20, 40 mg/kg) treatment significantly reduced acetic acid-induced writhings and ameliorated the formalin-induced inflammatory phase dose-dependently. Whereas, 40 mg/kg dose of β-sitosterol abrogated the formalin-induced neurogenic phase. Substance-P abrogated the effect of β-sitosterol in both neurogenic and inflammatory phases. Whereas, L-arginine only abrogated the inflammatory phase. In biochemical analysis, β-sitosterol treatment reduced the level of interleukin-6 (IL-6), thiobarbituric acid reactive substances (TBARS) and increased the level of reduced glutathione (GSH). Furthermore, L-arginine and substance-P abrogated the GSH increasing and TBARS lowering effect of β-sitosterol (40 mg/kg). Overall, the current study delineated that β-sitosterol may induce an anti-nociceptive effect via inhibiting the IL-6, oxidative stress, cyclo-oxygenase and nitric oxide.

Extracellular stimulation of lung fibroblasts with arachidonic acid increases interleukin 11 expression through p38 and ERK signaling

Interleukin-11 (IL-11) is a pleiotropic cytokine that regulates proliferation and motility of cancer cells. Fibroblasts reside in the cancer microenvironment and are the primary source of IL-11. Activated fibroblasts, including cancer-associated fibroblasts that produce IL-11, contribute to the development and progression of cancer, and induce fibrosis associated with cancer. Changes in fatty acid composition or its metabolites, and an increase in free fatty acids have been observed in cancer. The effect of deregulated fatty acids on the development and progression of cancer is not fully understood yet. In the present study, we investigated the effects of fatty acids on mRNA expression and secretion of IL-11 in lung fibroblasts. Among the eight fatty acids added exogenously, arachidonic acid (AA) increased mRNA expression and secretion of IL-11 in lung fibroblasts in a dose-dependent manner. AA-induced upregulation of IL-11 was dependent on the activation of the p38 or ERK MAPK signaling pathways. Furthermore, prostaglandin E2, associated with elevated cyclooxygenase-2 expression, participated in the upregulation of IL-11 via its specific receptor in an autocrine/paracrine manner. These results suggest that AA may mediate IL-11 upregulation in lung fibroblasts in the cancer microenvironment, accompanied by unbalanced fatty acid composition.

Renal interstitial cells promote nephron regeneration by secreting prostaglandin E2

In organ regeneration, progenitor and stem cells reside in their native microenvironment, which provides dynamic physical and chemical cues essential to their survival, proliferation, and differentiation. However, the types of cells that form the native microenvironment for renal progenitor cells (RPCs) have not been clarified. Here, single-cell sequencing of zebrafish kidney reveals fabp10a as a principal marker of renal interstitial cells (RICs), which can be specifically labeled by GFP under the control of fabp10a promoter in the fabp10a:GFP transgenic zebrafish. During nephron regeneration, the formation of nephrons is supported by RICs that form a network to wrap the RPC aggregates. RICs that are in close contact with RPC aggregates express cyclooxygenase 2 (Cox2) and secrete prostaglandin E2 (PGE2). Inhibiting PGE2 production prevents nephrogenesis by reducing the proliferation of RPCs. PGE2 cooperates with Wnt4a to promote nephron maturation by regulating β-catenin stability of RPC aggregates. Overall, these findings indicate that RICs provide a necessary microenvironment for rapid nephrogenesis during nephron regeneration.

PGE2 pathway mediates oxidative stress-induced ferroptosis in renal tubular epithelial cells

Prostaglandin E2 (PGE2) is one of the most abundant prostaglandins and has been implicated in various diseases. Here, we aimed to explore the role of the PGE2 pathway in mediating ferroptosis during acute kidney injury. When renal tubular epithelial cells stimulated by H₂ O₂ , the contents of glutathione (GSH) and glutathione peroxidase 4 (GPX4) decreased, whereas the level of lipid peroxide increased. Ferrostatin-1 can effectively attenuate these changes. In this process, the expression levels of cyclooxygenase (COX)-1 and COX-2 were up-regulated. Meanwhile, the expression of microsomal prostaglandin E synthase-2 was elevated, whereas the expression of microsomal prostaglandin E synthase-1 and cytosolic prostaglandin E synthase were down-regulated. Furthermore, the expression of 15-hydroxyprostaglandin dehydrogenase decreased. An excessive accumulation of PGE2 promoted ferroptosis, whereas the PGE2 inhibitor pranoprofen minimized the changes for COX-2, GSH, GPX4 and lipid peroxides. A decrease in the levels of the PGE2 receptor E-series of prostaglandin 1/3 partially restored the decline of GSH and GPX4 levels and inhibited the aggravation of lipid peroxide. Consistent with the in vitro results, increased PGE2 levels led to increased levels of 3,4-methylenedioxyamphetamine, Fe²⁺ accumulation and decreased GSH and GPX4 levels during renal ischaemia/reperfusion injury injury in mice. Our results indicate that the PGE2 pathway mediated oxidative stress-induced ferroptosis in renal tubular epithelial cells.

Aspirin mediates protection from diabetic kidney disease by inducing ferroptosis inhibition

Diabetic kidney disease (DKD) progression can be predicted by abnormalities in the tubulointerstitial lining, and their treatment may be useful for preventing the disease. DKD is a progressive disease that contributes to renal tubular cell death, but its underlying mechanisms remain unclear. Ferroptosis is a novel term linked to lipid hydroperoxidation, and it plays an important role in the pathogenesis of DKD. Overexpression of cyclooxygenase-2 (COX2), an enzyme of the proximal tubule, causes cellular redox damage in DKD. It remains unknown whether COX2 exacerbates tubular damage by accelerating ferroptosis in the kidneys of diabetic mice. HK-2 cells cultured in high glucose exhibited ferroptosis, which was inhibited by ferroptosis inhibitors. Additionally, alterations in the sensors of ferroptosis metabolism, such as glutathione peroxidase 4 (GPX4) activity, lipid hydroperoxidation, reduced glutathione (GSH) levels and changes in mitochondrial morphology, were observed in high glucose-cultured HK-2 cells. Diabetic mice manifested tubular injury and deranged renal physiological indices, which were mitigated by ferrostatin-1 (Fer-1). Importantly, these perturbations were ameliorated by downregulating COX2. In addition, the increased COX2 was observed to be elevated in the daibetic kindney. To explore the relevance of COX2 to ferroptosis, HK-2 cells that knocked down from COX2 exhibited decreased ferroptosis sensitivity under high glucose conditions. In RSL-3-treated HK-2 cells, ferroptosis was improved by downregulating COX2 by treatment with aspirin, which was confirmed in high glucose-cultured HK-2 cells. Furthermore, the ferroptosis changes were also suppressed by decreasing COX2 in diabetic mice treated with aspirin, which retarded DKD progression. In conclusion, our results demonstrated that ferroptosis in renal tubular cells contributes to DKD development and that diabetes-related ferroptosis was inhibited through the downregulation of COX2 by aspirin, thus retarding the progression of DKD. Our findings support a renoprotective mechanism by which aspirin inhibits COX2 activation, identify COX2 as a potential target of ferroptosis, and establish that ferroptosis in renal tubular cells is an integral process in the pathogenesis of DKD regulated by COX2 expression profiles.

The FKBP51 Inhibitor SAFit2 Restores the Pain-Relieving C16 Dihydroceramide after Nerve Injury

Neuropathic pain is a pathological pain state with a broad symptom scope that affects patients after nerve injuries, but it can also arise after infections or exposure to toxic substances. Current treatment possibilities are still limited because of the low efficacy and severe adverse effects of available therapeutics, highlighting an emerging need for novel analgesics and for a detailed understanding of the pathophysiological alterations in the onset and maintenance of neuropathic pain. Here, we show that the novel and highly specific FKBP51 inhibitor SAFit2 restores lipid signaling and metabolism in nervous tissue after nerve injury. More specifically, we identify that SAFit2 restores the levels of the C16 dihydroceramide, which significantly reduces the sensitization of the pain-mediating TRPV1 channel and subsequently the secretion of the pro-inflammatory neuropeptide CGRP in primary sensory neurons. Furthermore, we show that the C16 dihydroceramide is capable of reducing acute thermal hypersensitivity in a capsaicin mouse model. In conclusion, we report for the first time the C16 dihydroceramide as a novel and crucial lipid mediator in the context of neuropathic pain as it has analgesic properties, contributing to the pain-relieving properties of SAFit2.

Influence of tramadol on bacterial burden in the standard neutropenic thigh infection model

The neutropenic thigh infection model is one of the standard models in pharmacokinetic/ pharmacodynamic (PK/PD) characterization of novel antibacterials which are urgently needed due to the rise of antimicrobial resistance. The model enables to investigate PK/PD parameters crucial for translation of animal results towards humans. However, the neutropenic thigh infection model can result in moderate to severe discomfort of the animals, especially when high inocula are used. Tramadol has been proven to reduce pain effectively. This study investigates if tramadol influences the bacterial burden in the primary organ, the thighs, and organs affected by secondary seeding. Therefore, several strains of the ESKAPE pathogens, namely S. aureus, P. aeruginosa, K. pneumoniae, E. coli, A. baumannii and E. faecalis were examined. It was shown that tramadol did not influence the bacterial burden neither in thighs nor in organs affected by secondary seeding for the strains of E. faecalis, S. aureus, P. aeruginosa, K. pneumoniae and E.coli tested here, whereas secondary seeding seemed to be affected by tramadol for the tested strain of A. baumannii. Consequently, it was demonstrated that tramadol is an option to reduce discomfort in the untreated group for the strains of five out of the six tested ESKAPE pathogens and, thereby, contributes to the refinement of one of the standard PK/PD models.

Prostacyclin Regulation of Allergic Inflammation

Prostacyclin is a metabolic product of the cyclooxygenase pathway that is constitutively expressed and can be induced during inflammatory conditions. While prostacyclin and its analogs have historically been considered effective vasodilators and used in treating pulmonary hypertension, prostacyclin has demonstrated potent anti-inflammatory effects in animal models of allergic airway inflammation. In vitro studies reveal that prostacyclin directly inhibits type 2 cytokine production from CD4+ Th2 cells and ILC2 and reduces the ability of dendritic cells to generate Th2 cytokine production from CD4+ T cells in an antigen-specific manner. Thus, there is strong evidence that prostacyclin may be an additional therapeutic target for treating allergic inflammation and asthma in human subjects.

Punicalagin Attenuates LPS-Induced Inflammation and ROS Production in Microglia by Inhibiting the MAPK/NF-κB Signaling Pathway and NLRP3 Inflammasome Activation

Purpose

Neurodegenerative diseases are associated with neuroinflammation along with activation of microglia and oxidative stress, but currently lack effective treatments. Punicalagin is a natural bio-sourced product that exhibits anti-inflammatory effects on several chronic diseases; however, the anti-inflammatory and anti-oxidative effects on microglia have not been well examined. This study aimed to investigate the effects of punicalagin on LPS-induced inflammatory responses, NLRP3 inflammasome activation, and the production of ROS using murine microglia BV2 cells.

Methods

BV2 cells were pre-treated with punicalagin following LPS treatment to induce inflammation. The secretion of NO and PGE₂ was analyzed by Griess reagent and ELISA respectively, while the expressions of iNOS, COX-2, STAT3, ERK, JNK, and p38 were analyzed using Western blotting, the production of IL-6 was measured by ELISA, and the activity of NF-κB was detected using promoter reporter assay. To examine whether punicalagin affects NLRP3 inflammasome activation, BV2 cells were stimulated with LPS and then treated with ATP or nigericin. The secretion of IL-1β was measured by ELISA. The expressions of NLRP3 inflammasome-related proteins and phospho IκBα/IκBα were analyzed using Western blotting. The production of intracellular and mitochondrial ROS was analyzed by flow cytometry.

Results

Our results showed that punicalagin attenuated inflammation with reduction of pro-inflammatory mediators and cytokines including iNOS, COX-2, IL-1β, and reduction of IL-6 led to inhibition of STAT3 phosphorylation by LPS-induced BV2 cells. Punicalagin also suppressed the ERK, JNK, and p38 phosphorylation, attenuated NF-κB activity, inhibited the activation of the NLRP3 inflammasome, and reduced the production of intracellular and mitochondrial ROS by LPS-induced BV2 cells.

Conclusion

Our results demonstrated that punicalagin attenuated LPS-induced inflammation through suppressing the expression of iNOS and COX-2, inhibited the activation of MAPK/NF-κB signaling pathway and NLRP3 inflammasome, and reduced the production of ROS in microglia, suggesting that punicalagin might have the potential in treating neurodegenerative diseases.

Hypertension and renal disease programming: focus on the early postnatal period

The developmental origin of hypertension and renal disease is a concept highly supported by strong evidence coming from both human and animal studies. During development there are periods in which the organs are more vulnerable to stressors. Such periods of susceptibility are also called 'sensitive windows of exposure'. It was shown that as earlier an adverse event occurs; the greater are the consequences for health impairment. However, evidence show that the postnatal period is also quite important for hypertension and renal disease programming, especially in rodents because they complete nephrogenesis postnatally, and it is also important during preterm human birth. Considering that the developing kidney is vulnerable to early-life stressors, renal programming is a key element in the developmental programming of hypertension and renal disease. The purpose of this review is to highlight the great number of studies, most of them performed in animal models, showing the broad range of stressors involved in hypertension and renal disease programming, with a particular focus on the stressors that occur during the early postnatal period. These stressors mainly include undernutrition or specific nutritional deficits, chronic behavioral stress, exposure to environmental chemicals, and pharmacological treatments that affect some important factors involved in renal physiology. We also discuss the common molecular mechanisms that are activated by the mentioned stressors and that promote the appearance of these adult diseases, with a brief description on some reprogramming strategies, which is a relatively new and promising field to treat or to prevent these diseases.

The association of urinary prostaglandins with uric acid in hyperuricemia patients

Purpose

To explore the association between uric acid and urinary prostaglandins in male patients with hyperuricemia.

Methods

A total of 38 male patients with hyperuricemia in outpatients of Huadong Hospital from July 2018 to January 2020 were recruited. Serum uric acid (SUA), 24 h urinary uric acid excretion and other indicators were detected respectively. 10 ml urine was taken to determine prostaglandin prostaglandin D (PGD), prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), 6-keto-PGF1α, thromboxane A2 (TXA2) and thromboxane B2 (TXB2). Fraction of uric acid excretion (FEua) and uric acid clearance rate (Cua) were calculated. According to the mean value of FEua and Cua, patients were divided into two groups, respectively. The independent-samples t test and the Mann–Whitney U test were applied for normally and non-normally distributed data, respectively.

Results

After adjusting confounding factors (age, BMI, eGFR, TG, TC, HDL and LDL), SUA was negatively correlated with urinary PGE1(r = -0.615, P = 0.009) and PGE2(r = -0.824, P < 0.001). Compared with SUA1 group (SUA < 482.6 mg/dl), SUA2 (SUA \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 482.6 mg/dl) had lower urinary PGE1(P = 0.022) and PGE2(P = 0.019) levels. Cua was positively correlated with PGE2 (r = 0.436, P = 0.01). The correlation persisted after adjustment for age, BMI, eGFR, TG, TC, HDL and LDL by multiple linear regression analysis. In the Cua1 group (Cua < 4.869 mL /min/1.73 m²), PGE2 were lower than that in Cua2 (Cua \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 4.869 mL /min/1.73 m²) group (P = 0.011).

Conclusions

In male patients with hyperuricemia, SUA was negatively correlated with urinary PGE2, Cua was positively correlated with urinary PGE2. Urinary PGE2 were significantly different between different SUA and Cua groups.

Anti-inflammatory activity and cytotoxicity against ovarian cancer cell lines by amide alkaloids and piperic esters isolated from Piper longum fruits: In vitro assessments and molecular docking simulation

Three new amide alkaloids, piperlongumamides D-F (14, 19, and 32); a new piperic ester, piperlongumester A (45); and two new natural compounds, methyl (2E,4Z)-5-(1,3-benzodioxol-5-yl)penta-2,4-dienoate (46) and trans-piperolein B ester (47), along with 41 known compounds were isolated from the fruits of Piper longum L. Their structures were identified by analyzing spectroscopic data, including mass spectrometry, 1D, and 2D NMR data. The anti-inflammatory and cytotoxic activities of all isolated compounds (1-47) were evaluated. Compounds 3, 6, and 19 inhibited nitric oxide production with IC₅₀ values of 16.1 ± 0.94, 14.5 ± 0.57, and 27.3 ± 1.11 μM, respectively, whereas compound 1 exhibited strong cytotoxic activity toward three ovarian cancer cell lines A2780, TOV-112D, and SK-OV3, with IC₅₀ values of 6.7 ± 0.77, 5.8 ± 0.29, and 48.3 ± 0.40 μM, respectively. Molecular docking simulations were performed to identify the interaction and binding mechanisms of these active metabolites with proteins related to inflammation and cancer.

Effect of Meloxicam on the Proliferation and Apoptosis of the Raji Cell Line: an In Vitro Study

Meloxicam, a nonsteroidal anti-inflammatory drug, inhibits the production of PGE2 by blocking Cox-2 activity. Specific inhibition of Cox-2 can be useful in cancer therapy by apoptosis stimulation. The objective of the research was to study the effect of meloxicam on the proliferation and apoptosis of Raji cell lines. Burkitt lymphoma (BL) cells (Raji ATCC CCL-86) were treated with various concentrations of meloxicam for 24 hours. The proliferation of the cells was evaluated by using an MTT assay. Cell apoptosis was assessed using flow cytometry, and SEM was performed to observe the morphological changes of the cells. Results showed that meloxicam affected Raji cell proliferation as well as cell apoptosis. The percentage of viable cells was decreased significantly after being treated with meloxicam (p < 0.05). Apoptotic cell percentage was higher in the groups treated with meloxicam compared to the control group (p < 0.05). SEM showed morphological changes in the Raji cells after treatment with meloxicam, showing apoptotic characteristics. These findings suggest that meloxicam has anticancer properties by inhibiting Raji cell proliferation and inducing Raji cell apoptosis in vitro. A combination of meloxicam with chemotherapy agents may improve the outcome of BL treatment.

Reverting to a healthy diet during lactation normalizes maternal milk lipid content of diet-induced obese rats and prevents early alterations in the plasma lipidome of the offspring

Scope

This study aims to assess in rats whether normalizing maternal diet during lactation prevents the harmful effects of western diet (WD) consumption during the whole perinatal period on the lipidomic profile in maternal milk and offspring plasma.

Methods and Results

Control dams (CON‐dams), fed with standard diet (SD); WD‐dams, fed with WD prior and during gestation and lactation; and reversion dams (REV‐dams), fed as WD‐dams but moved to SD during lactation are followed. Lipidomic analysis is performed in milk and plasma samples from pups. Milk of WD‐dams presents a different triacylglycerol composition and free fatty acid (FA) profile compared to CON‐dams, including an increased ratio of pro‐inflammatory to anti‐inflammatory long‐chain polyunsaturated FA. Such alterations, which are also present in the plasma of their offspring, are widely reversed in the milk of REV‐dams and the plasma of their pups. This is related with the recovery of control adiponectin expression levels in the mammary gland, and the presence of decreased expression of pro‐inflammatory factors.

Conclusion

Implementing a healthy diet during lactation prevents early alterations in the plasma lipidome of pups associated to the maternal intake of an obesogenic diet, which may be related to the normalization of milk lipid content and the inflammatory state in the mammary gland.

Acupuncture for Knee Osteoarthritis: A Systematic Review of Randomized Clinical Trials with Meta-Analyses and Trial Sequential Analyses

Background

Knee osteoarthritis (KOA) can cause chronic pain and seriously affect the quality of patient lives. The continued emergence of high-quality RCTS requires us to update the quality of evidence. This study aims to evaluate the efficacy of acupuncture for KOA patients and calculate the required information size (RIS) to determine whether further clinical studies are required.

Methods

We searched PubMed, Embase, WOS, CBM, CNKI, VIP, WHO ICTRP, ChiCTR, and Grey literature to collect randomized controlled trials (RCTs) of acupuncture for KOA from inception to December 2021. A meta-analysis was performed according to the Cochrane systematic review method by using Review Manager 5.4 and TSA 0.9.5.10 beta, and GRADE was used to evaluate the quality of the evidence. Trial sequential analysis was used to control random errors and calculate the required information size.

Results

Eleven RCTs with 2484 patients were included in our meta-analysis, meeting the inclusion criteria for the meta-analysis. The meta-analysis indicated that acupuncture had beneficial effect on knee osteoarthritis in reducing pain [n = 2387; SMD = -0.12, 95% CI (-0.20, -0.04); I 2 = 0%] and improved patients function activities [n = 2408; MD = -1.25, 95% CI (-1.97, -0.53); I 2 = 0%], but true acupuncture showed no significant effect in relieve patient's stiffness [n = 1337; MD = -0.07, 95% CI (-0.30, 0.15); I 2 = 0%]. We pooled the studies which found no significant difference in improving the quality life of mental [n = 1462; SMD = 0.02, 95% CI (-0.23, 0.27); I 2 = 78%] and patients physical health (SF-36 or SF-12) [n = 1745; SMD = 1.01, 95% CI (-0.08, 2.11); I 2 = 0%] compared with sham acupuncture. The pain and function TSA graphs indicated that cumulative Z-curves intersected with the traditional level of statistical favoring acupuncture, and more RCTs will required in the future studies.

Conclusion

Acupuncture has beneficial effect on pain relief and improves function activities, and this treatment can be recommended as a beneficial alternative therapy in patients with KOA, particularly for chronic patients and those currently undergoing long-term pain and help them increasing quality of life. But it should be further verified through more RCTs in function. Available studies suggested that acupuncture was superior to sham acupuncture in reduce pain and function as verified by TSA.

Therapeutic effect of quercetin polymeric nanoparticles on ischemia/reperfusion-induced acute kidney injury in mice

Acute kidney injury (AKI) is known as a sudden episode of kidney injury, which happens suddenly within a few hours or a few days. Quercetin (3,3',4',5,7-pentahydroxyflavone) is a flavonoid found in plants. Quercetin is known to have several biological activities, such as anti-oxidant, anti-inflammatory, and anti-carcinogenic effects. However, low water solubility and bioavailability are the limitations of quercetin for its clinical applications. Moreover, ischemia/reperfusion (I/R) injury is a common cause of AKI. There are no satisfactory strategies for I/R-induced AKI. Developing suitable preventive or therapeutic intervention for AKI is an important and urgent issue. We investigated the benefit effect of synthesized polyethylene glycol (PEG) conjugated polyethyleneimine (PEI) nanoparticles for targeted delivery of quercetin on AKI in a mouse model. An I/R-induced AKI mouse model was used to evaluate the therapeutic effect of quercetin polymeric nanoparticles by intravenous injection. Biochemical changes for renal function in blood samples were analyzed. Histological and immunohistochemical changes were also analyzed. The biochemical changes of blood urea nitrogen (BUN), creatinine, and cystatin C were significantly increased in I/R-induced AKI mice, which could be significantly reversed by quercetin polymeric nanoparticles. Quercetin polymeric nanoparticles could also significantly decrease the histological lesions, positive staining for 3-nitrotyrosine and cyclooxygenase-2, and lipid peroxidation in the kidneys of I/R-induced AKI mice. These results demonstrate for the first time that quercetin polymeric nanoparticles possess therapeutic potential for the treatment of I/R-induced AKI in vivo.

A Systematic Review of the Effect of Centella asiatica on Wound Healing

BACKGROUND

Under metabolic stress conditions, there is a higher demand for nutrients which needs to be met. This is to reduce the risk of delay in wound healing which could lead to chronic wound.

AIM

This is a systematic review of the effect of Centella asiatica on wound healing. C. asiatica is a traditional medicinal plant used due to its antimicrobial, antioxidant, anti-inflammatory, neuroprotective, and wound healing properties.

METHODS

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were followed for the systematic review and four electronic databases were used.

RESULTS

Four clinical trials met the inclusion criteria. The following distinct areas were identified under C. asiatica: wound contraction and granulation; healing/bleeding time and re-epithelialization; VAS (visual analogue scale) scores; skin erythema and wound appearance.

CONCLUSIONS

C. asiatica might enhance wound healing resulting from improved angiogenesis. This might occur due to its stimulating effect on collagen I, Fibroblast Growth Factor (FGF) and Vascular Endothelial Growth Factor (VEGF) production. Besides, C. asiatica has shown an anti-inflammatory effect observed by the reduction in Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and Tumour Necrosis Factor α (TNFα), prostaglandin E2 (PGE2), cyclooxygenase-2 (COX-2), and lipoxygenase (LOX) activity. Delivery systems such as nanoencapsulation could be used to increase C. asiatica bioavailability. Nevertheless, more studies are needed in order to perform a meta-analysis and ascertain the effects of C. asiatica on wound healing and its different parameters.

Molecular docking prediction and in vitro studies elucidate anti-inflammatory effect of Garcinia extract against inducible nitric oxide synthase and cyclooxygenase-2 targets

Background

Garcinia is a tropical plant that has been traditionally used in medicinal folklore for its potential antioxidant, antibacterial, anti-hyperlipidemic, anti-diabetic, hepatoprotective, etc. In this study, methanolic extract of Garcinia herbal supplement (GME) and its important phytoconstituents (Garcinol and hydroxycitric acid) were evaluated for their inhibitory action against important inflammatory markers iNOS and COX-2 in lipopolysaccharide-induced RAW 264.7 cells. iNOS and COX-2 play a major role in the process of inflammation, and inhibition of these molecules will help to alleviate the inflammatory process. The cells were pre-treated with two doses of GME (115 µg/ml and 230 µg/ml); Ggarcinol (6 µM and 12 µM); hydroxycitric acid (17.5 µg/ml and 35 µg/ml) followed by stimulation with 1 µg/ml of LPS for 24 h.

Results

The results of the study demonstrated that Garcinia and its active components Garcinol and HCA play an important role in suppressing LPS-induced relative mRNA expression of iNOS, COX-2, and subsequent reduction in the levels of total nitric oxide and prostaglandinE2. Molecular docking analysis of Ggarcinol and HCA with iNOS and COX-2 proteins showed potent interactions with negative binding energies.

Conclusions

This study suggests that Garcinia possess anti-inflammatory activity thus providing a possibility for drug designing as iNOS and COX-2 inhibitor.

Graphical Abstract

Honey polyphenolic fraction inhibits cyclooxygenase-2 expression via upregulation of microRNA-26a-5p expression in pancreatic islets

Objectives

Honey total polyphenolic fraction (HTPF) is reported to have anti-disease potential, however the role of HTPF in the regulation of microRNAs (miRNAs) has never been investigated. This study was undertaken to investigate the potential of HTPF against inflammation via regulation of miRNAs in pancreatic islets of Langerhans.

Methods

Pancreatic islets were isolated from C57BL/6 mice and HTPF was purified from honey. Bioinformatics algorithms were used to determine miRNA target genes. Expression of miRNA and mRNA was determined using their specific taqman assays. Pairing between miRNA and 3′ untranslated region (3′UTR) of mRNA was confirmed using luciferase reporter clone containing the 3′UTR of mRNA sequences and results were verified by transfection of mouse pancreatic β-cell line Min6 with miRNA inhibitors.

Results

The data showed that mmu-miR-26a-5p is a direct regulator of cyclooxygenase-2 (COX-2) expression and HTPF inhibits COX-2 expression or prostaglandin E2 (PGE2) production via up-regulating mmu-miR-26a-5p expression. Transfection of islets with anti-miR-26a-5p significantly enhanced COX-2 expression and PGE2 production ( p < .01), while HTPF treatment significantly inhibited anti-miR-26a-5p transfection-induced COX-2 expression or PGE2 production ( p < .05). These findings were further verified in pancreatic β-cells Min6. Moreover, the data also determined that HTPF also inhibits glucose-induced nuclear transcription factor (NF)-κB activity.

Conclusion

HTPF suppresses glucose-induced PGE2 production and activation of NF-κB via negative regulation of COX-2 and mmu-miR26a-5p. These novel pharmacological actions of HTPF on glucose-stimulated pancreatic islets provide new suggestions that HTPF or HTPF-derived compounds inhibit glucose induced inflammation in pancreas by up-regulating the expression of microRNAs.

The Prostaglandin E2 Pathway and Breast Cancer Stem Cells: Evidence of Increased Signaling and Potential Targeting

Culprits of cancer development, metastasis, and drug resistance, cancer stem cells (CSCs) are characterized by specific markers, active developmental signaling pathways, metabolic plasticity, increased motility, invasiveness, and epithelial-mesenchymal transition. In breast cancer, these cells are often more prominent in aggressive disease, are amplified in drug-resistant tumors, and contribute to recurrence. For breast cancer, two distinct CSC populations exist and are typically defined by CD44+/CD24- cell surface marker expression or increased aldehyde dehydrogenase (ALDH) activity. These CSC populations share many of the same properties but also exhibit signaling pathways that are more active in CD44+/CD24- or ALDH+ populations. Understanding these CSC populations and their shared or specific signaling pathways may lead to the development of novel therapeutic strategies that will improve breast cancer patient outcomes. Herein, we review the current evidence and assess published patient tumor datasets of sorted breast CSC populations for evidence of heightened prostaglandin E2 (PGE₂) signaling and activity in these breast CSC populations. PGE₂ is a biologically active lipid mediator and in cancer PGE₂ promotes tumor progression and poor patient prognosis. Overall, the data suggests that PGE₂ signaling is important in propagating breast CSCs by enhancing inherent tumor-initiating capacities. Development of anti-PGE₂ signaling therapeutics may be beneficial in inhibiting tumor growth and limiting breast CSC populations.

Functional Selectivity of Coumarin Derivates Acting via GPR55 in Neuroinflammation

Anti-neuroinflammatory treatment has gained importance in the search for pharmacological treatments of different neurological and psychiatric diseases, such as depression, schizophrenia, Parkinson’s disease, and Alzheimer’s disease. Clinical studies demonstrate a reduction of the mentioned diseases’ symptoms after the administration of anti-inflammatory drugs. Novel coumarin derivates have been shown to elicit anti-neuroinflammatory effects via G-protein coupled receptor GPR55, with possibly reduced side-effects compared to the known anti-inflammatory drugs. In this study, we, therefore, evaluated the anti-inflammatory capacities of the two novel coumarin-based compounds, KIT C and KIT H, in human neuroblastoma cells and primary murine microglia. Both compounds reduced PGE₂-concentrations likely via the inhibition of COX-2 synthesis in SK-N-SH cells but only KIT C decreased PGE₂-levels in primary microglia. The examination of other pro- and anti-inflammatory parameters showed varying effects of both compounds. Therefore, the differences in the effects of KIT C and KIT H might be explained by functional selectivity as well as tissue- or cell-dependent expression and signal pathways coupled to GPR55. Understanding the role of chemical residues in functional selectivity and specific cell- and tissue-targeting might open new therapeutic options in pharmacological drug development and might improve the treatment of the mentioned diseases by intervening in an early step of their pathogenesis.

Novel benzofurane-pyrazole derivatives with anti-inflammatory, cyclooxygenase inhibitory and cytotoxicity evaluation

Novel benzofurane-pyrazolone hybrids have been synthesized for evaluating their anti-inflammatory and cytotoxic properties. 4-(2-chloroacetyl)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one were reacted with α-hydroxy aldehyde or α-hydroxy ketone derivatives to obtain nine novel pyrazolone derivatives. Structures were successfully elucidated by ¹H NMR, ¹³C NMR, IR and HRMS. Enzyme inhibitory activity was measured on cyclooxygenases (COXs) as considered to address anti-inflammatory activity. Compound 2 showed the highest activity on both COX-1 and COX-2 subtypes with 12.0 μM and 8.0 μM IC₅₀, respectively. This activity was found close to indomethacin COX-2 inhibition measured as 7.4 μM IC₅₀. Rest of the compounds (1, 3-9) showed 10.4-28.1 μM IC₅₀ on COX-2 and 17.0-35.6 μM IC₅₀ on COX-1 (Compound 1 has no activity on COX-1). Tested compounds (1-9) showed activity on NO production. Only compound was the 4, which showed a low inhibition on IL-6 levels. Cell viability was up to 60% at 100 μM for all compounds (1-9) on RAW 264.7 and NIH3T3 cell lines, thus compounds were reported to be noncytotoxic.

Anti-Inflammatory, Antioxidant, Moisturizing, and Antimelanogenesis Effects of Quercetin 3-O-β-D-Glucuronide in Human Keratinocytes and Melanoma Cells via Activation of NF-κB and AP-1 Pathways

Quercetin 3-O-β-D-glucuronide (Q-3-G), the glucuronide conjugate of quercetin, has been reported as having anti-inflammatory properties in the lipopolysaccharide-stimulated macrophages, as well as anticancer and antioxidant properties. Unlike quercetin, which has been extensively described to possess a wide range of pharmacological activities including skin protective effects, the pharmacological benefits and mechanisms Q-3-G in the skin remained to be elucidated. This study focused on characterizing the skin protective properties, including anti-inflammatory and antioxidant properties, of Q-3-G against UVB-induced or H₂O₂-induced oxidative stress, the hydration effects, and antimelanogenesis activities using human keratinocytes (HaCaT) and melanoma (B16F10) cells. Q-3-G down-regulated the expression of the pro-inflammatory gene and cytokine such as cyclooxygenase-2 (COX-2) and tumor necrosis factor (TNF)-α in H₂O₂ or UVB-irradiated HaCaT cells. We also showed that Q-3-G exhibits an antioxidant effect using free radical scavenging assays, flow cytometry, and an increased expression of nuclear factor erythroid 2- related factor 2 (Nrf2). Q-3-G reduced melanin production in α-melanocyte-stimulating hormone (α-MSH)-induced B16F10 cells. The hydration effects and mechanisms of Q-3-G were examined by evaluating the moisturizing factor-related genes, such as transglutaminase-1 (TGM-1), filaggrin (FLG), and hyaluronic acid synthase (HAS)-1. In addition, Q-3-G increased the phosphorylation of c-Jun, Jun N-terminal kinase (JNK), Mitogen-activated protein kinase (MAPK) kinase 4 (MKK4), and TAK1, involved in the MAPKs/AP-1 pathway, and the phosphorylation of IκBα, IκB kinase (IKK)-α, Akt, and Src, involved in the NF-κB pathway. Taken together, we have demonstrated that Q-3-G exerts anti-inflammatory, antioxidant, moisturizing, and antimelanogenesis properties in human keratinocytes and melanoma cells through NF-κB and AP-1 pathways.

Modulation of Enzyme-Catalyzed Synthesis of Prostaglandins by Components Contained in Kidney Microsomal Preparations

In the kidney, prostaglandins formed by cyclooxygenase 1 and 2 (COX-1 and COX-2) play an important role in regulating renal blood flow. In the present study, we report our observations regarding a unique modulatory effect of renal microsomal preparation on COX-1/2-mediated formation of major prostaglandin (PG) products in vitro. We found that microsomes prepared from pig and rat kidneys had a dual stimulatory–inhibitory effect on the formation of certain PG products catalyzed by COX-1 and COX-2. At lower concentrations, kidney microsomes stimulated the formation of certain PG products, whereas at higher concentrations, their presence inhibited the formation. Presence of kidney microsomes consistently increased the K_m values of the COX-1/2-mediated reactions, while the V_max might be increased or decreased depending on stimulation or inhibition observed. Experimental evidence was presented to show that a protein component present in the pig kidney microsomes was primarily responsible for the activation of the enzyme-catalyzed arachidonic acid metabolism leading to the formation of certain PG products.

Constructing a cell microenvironment with biomaterial scaffolds for stem cell therapy

Stem cell therapy is widely recognized as a promising strategy for exerting therapeutic effects after injury in degenerative diseases. However, limitations such as low cell retention and survival rates after transplantation exist in clinical applications. In recent years, emerging biomaterials that provide a supportable cellular microenvironment for transplanted cells have optimized the therapeutic efficacy of stem cells in injured tissues or organs. Advances in the engineered microenvironment are revolutionizing our understanding of stem cell-based therapies by co-transplanting with synthetic and tissue-derived biomaterials, which offer a scaffold for stem cells and propose an unprecedented opportunity to further employ significant influences in tissue repair and regeneration.

Renal subcapsular delivery of PGE2 promotes kidney repair by activating endogenous Sox9+ stem cells

Prostaglandin E₂ (PGE₂) has recently been recognized to play a role in immune regulation and tissue regeneration. However, the short half-life of PGE₂ limits its clinical application. Improving the delivery of PGE₂ specifically to the target organ with a prolonged release method is highly desirable. Taking advantage of the adequate space and proximity of the renal parenchyma, renal subcapsular delivery allows minimally invasive and effective delivery to the entire kidney. Here, we report that by covalently cross-linking it to a collagen matrix, PGE₂ exhibits an adequate long-term presence in the kidney with extensive intraparenchymal penetration through renal subcapsular delivery and significantly improves kidney function. Sox9 cell lineage tracing with intravital microscopy revealed that PGE₂ could activate the endogenous renal progenitor Sox9⁺ cells through the Yap signaling pathway. Our results highlight the prospects of utilizing renal subcapsular-based drug delivery and facilitate new applications of PGE₂-releasing matrices for regenerative therapy.

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PGE₂ exhibits an adequate long-term release by being covalently cross-linked to collagen

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The renal subcapsular space serves as a reservoir for the delivery of PGE₂

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Sox9⁺ renal progenitor cells can be lineage traced intravitally by microscopy

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PGE₂ activates the endogenous renal progenitor Sox9⁺ cells through the YAP pathway

Celecoxib decreases mitochondrial complex IV activity and induces oxidative stress in isolated rat heart mitochondria: An analysis for its cardiotoxic adverse effect

In spite of the cardiotoxic effect of selective cyclooxygenase-2 inhibitors, they are most widely used as anti-inflammatory and analgesic drugs. Today, valdecoxib and rofecoxib have been withdrawn in the market but celecoxib remains. In this study, we focused on an analysis of celecoxib toxic effects on isolated mitochondria. Isolated rat heart mitochondria were obtained using differential centrifugation. Using flow cytometry and biochemical assays, we searched succinate dehydrogenases, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) formation, mitochondrial swelling, ATP/ADP ratio, lipid peroxidation, and mitochondrial complexes activity in rat heart isolated mitochondria. Herein, our results indicated a significant decrease in the activity of complex IV after exposure with celecoxib (16 µg/ml). This decrease in the activity of complex IV is paralleled by the MMP collapse, ROS formation, mitochondrial swelling, depletion of ATP, and lipid peroxidation. For the first time, this introductory study has shown a significant decrease in the activity of complex IV and mitochondrial dysfunction after exposure with celecoxib in rat heart isolated mitochondria.