Anti-Inflammatory and Anti-Hyperuricemic Functions of Two Synthetic Hybrid Drugs with Dual Biological Active Sites

Hydroxycitric acid and capsaicin combination alleviates obesity-induced testicular apoptosis, oxidative stress and inflammation

Recent research in rodents suggests that oxidative stress, inflammation, and apoptosis in the testes caused by high-fat diets (HFD) are a cause of male infertility. To investigate the therapeutic efficacy of the combination of hydroxycitric acid and capsaicin (HCC) against male reproductive disorders, we developed an HFD-induced obese rat model. Rats received HFD supplementation for 21 weeks, which induced obesity. From week 16, HCC (100 mg/kg body weight) was administered to investigate its potential to treat testicular toxicity. According to the results of the current study, treatment of obese rats with HCC improved their sperm quality, increased the production of testosterone, follicle-stimulating hormone, and luteinizing hormone and significantly increased the activities of steroidogenic enzymes and corresponding mRNA levels. In addition, HCC decreased lipid peroxidation and nitric oxide levels in both spermatozoa and testes while increasing the expression of mRNA for the antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase in the testes, which in turn reduced oxidative stress in the testes. Moreover, after HCC treatment, testicular tissues showed a remarkable decrease in mRNA levels responsible for inflammation (TNF-α, IL-6, NF-κB) and apoptosis (Bax and Bcl-2). Our results suggest that HCC may alleviate obesity-induced male reproductive dysfunction by attenuating oxidative stress, inflammation, and apoptosis in the testes of HFD-induced obese male rats.

Exploring Asphodelus microcarpus as a source of xanthine oxidase inhibitors: Insights from in silico and in vitro studies

Xanthine oxidase (XO) plays a critical role in purine catabolism, catalyzing the conversion of hypoxanthine to xanthine and xanthine to uric acid, contributing to superoxide anion production. This process is implicated in various human diseases, particularly gout. Traditional XO inhibitors, such as allopurinol and febuxostat, while effective, may present side effects. Our study focuses on Asphodelus microcarpus, a plant renowned for traditional anti-inflammatory uses. Recent investigations into its phenolic-rich flowers, notably abundant in luteolin derivatives, reveal its potential as a natural source of XO inhibitors. In the present research, XO inhibition by an ethanolic flowers extract from A. microcarpus is reported. In silico docking studies have highlighted luteolin derivatives as potential XO inhibitors, and molecular dynamics support that luteolin 7-O-glucoside has the highest binding stability compared to other compounds and controls. In vitro studies confirm that luteolin 7-O-glucoside inhibits XO more effectively than the standard inhibitor allopurinol, with an IC50 value of 4.8 μg/mL compared to 11.5 μg/mL, respectively. These findings underscore the potential therapeutic significance of A. microcarpus in managing conditions related to XO activity. The research contributes valuable insights into the health-promoting properties of A. microcarpus and its potential application in natural medicine, presenting a promising avenue for further exploration in disease management.

Chicoric acid enhances the antioxidative defense system and protects against inflammation and apoptosis associated with the colitis model induced by dextran sulfate sodium in rats

Although several anticolitic drugs are available, their application is associated with numerous side effects. Chicoric acid (CA) is a hydroxycinnamic acid found naturally in chicory (Cichorium intybus), purple coneflower (Echinacea purpurea), and basil with numerous health benefits, such as antioxidative and anti-inflammatory activities. Here, the potential anticolitic efficiency of CA against dextran sulfate sodium (DSS)-induced colitis in rats was examined in rats. Animals were randomly assigned to the following five groups: control, CA (100 mg/kg body weight), DSS [(DSS); 4% w/v], CA + DSS (100 mg/kg), and the 5-aminosalicylic acid (100 mg/kg) + DSS group. The obtained data revealed that CA significantly prevented the shortening of colon length. Meanwhile, the oxidative stress-related enzymes were increased, while malondialdehyde and nitric oxide, were markedly decreased significantly by CA. The results also indicated that CA administration decreased significantly the pro-apoptogenic indices (Bax and caspase-3) and enhanced significantly Bcl-2, the anti-apoptogenic protein. Moreover, DSS caused a significant elevation of pro-inflammatory mediators, including interleukin-1β, tumor necrosis factor-α, myeloperoxidase, cyclooxygenase II, prostaglandin E2, and peroxisome proliferator-activated receptor gamma. Interestingly, these changes were significantly decreased following the CA administration. At the molecular level, CA supplementation has increased significantly the expression level of nuclear factor erythroid 2-related factor-2 (Nrf2) and decreased the expressions of nitric oxide synthase and mitogen-activated protein kinase 14. CA has been determined to significantly lessen DSS-induced colitis by activating Nrf2 and its derived antioxidant molecules and suppressing inflammation and apoptosis cascades associated with the development of colitis; suggesting that CA could be used as an alternative naturally-derived anticolitic agent.

Towards the Development of Dual Hypouricemic and Anti-inflammatory Candidates: Design, Synthesis, Stability Studies and Biological Evaluation of Some Mutual Ester Prodrugs of Febuxostat-NSAIDs

Treatment of gout involves two basic approaches: reducing the serum uric acid mainly by xanthine oxidase inhibitors (XOIs) and alleviating the intensity of the accompanying acute arthritic inflammation using non-steroidal anti-inflammatory drugs (NSAIDs). Febuxostat (FEB) is the first non-purine XOI approved for the treatment of hyperuricemia and gout. The present study aims at combining the hypouricemic effect of FEB and the anti-inflammatory (AI) properties of NSAIDs in a single entity by adopting the "mutual prodrug" approach. Accordingly, a series of seven ester prodrugs comprising basically FEB together with different NSAIDs namely, diclofenac (4), ibuprofen (5), ketoprofen (6), indomethacin (7), naproxen (8), ketorolac (9) and etodolac (10) was synthesized. All the investigated seven prodrugs (4-10) were equipotent or even superior to their corresponding parent drugs in the hypouricemic and AI activities, together with a gastrointestinal (GI) safety profile. Among this series, the prodrug FEB-DIC (4) showed excellent dual in vivo hypouricemic and anti-inflammatory activity (43.60 % and 15.96 %, respectively) when compared to the parent drugs FEB and diclofenac (36.82 % and 12.10 %, respectively) and its physical mixture (37.28 % and 12.41 %, respectively). Investigation of the in vitro chemical stability and hydrolysis of the prodrug (4) in aqueous and biological samples using a developed HPLC method confirmed its stability in various pHs, whereas rapid hydrolysis to the parent drugs in liver homogenate and human plasma was proven. Finally, it is concluded that the mutual prodrug approach could be successfully used in drug design and development for overcoming undesirable difficulties without losing the desired activities of the parent drugs.

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

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

Protocatechuic acid counteracts oxidative stress and inflammation in carrageenan-induced paw edema in mice

Protocatechuic acid (PCA), a phenolic compound found in teas, fruits, and vegetables, is widely recognized with its antioxidant and anti-inflammatory activities. Here, we verified the protective role of PCA on carrageenan (CGN)-induced paw edema in mice. Forty-five male Swiss albino mice were assigned into five groups: control group, CGN-injected group (1% w/v), PCA (25 mg/kg) + CGN group. PCA (50 mg/kg) + CGN group and diclofenac sodium (20 mg/kg) + CGN group. PCA and diclofenac sodium were administered orally for 5 consecutive days prior to the CGN injection. PCA pretreatment notably decreased the volume of the developed edema and alleviated the histopathological alterations induced by carrageenan. Additionally, PCA administration enhanced the cellular antioxidant capacity as demonstrated by the increased levels of catalase, superoxide dismutase, and reduced glutathione, in addition to the decreased malondialdehyde level in the edematous tissue. Interestingly, PCA administration was able significantly to suppress the developed inflammatory response upon carrageenan injection as indicated by the decreased levels and expression of pro-inflammatory cytokines and mediators including tumor necrosis factor alpha, interleukin-1 beta, interleukin-6, inducible nitric oxide synthase, nitric oxide, cyclooxygenase-II, prostaglandin E2, monocyte chemoattractant protein-1, myeloperoxidase and nuclear factor kappa B. These results collectively confirm the protective effect of PCA against carrageenan-induced paw edema owing to its antioxidant and anti-inflammatory characteristics.

Mechanistic evaluation of a novel cyclohexenone derivative's functionality against nociception and inflammation: An in-vitro, in-vivo and in-silico approach

The synthesis of a novel cyclohexanone derivative (CHD; Ethyl 6-(4-metohxyphenyl)-2-oxo-4-phenylcyclohexe-3-enecarboxylate) was described and the subsequent aim was to perform an in vitro, in vivo and in silico pharmacological evaluation as a putative anti-nociceptive and anti-inflammatory agent in mice. Initial in vitro studies revealed that CHD inhibited both cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LOX) enzymes and it also reduced mRNA expression of COX-2 and the pro-inflammatory cytokines TNF-α and IL-1β. It was then shown that CHD dose dependently inhibited chemically induced tonic nociception in the abdominal constriction assay and also phasic thermal nociception (i.e. anti-nociception) in the hot plate and tail immersion tests in comparison with aspirin and tramadol respectively. The thermal test outcomes indicated a possible moderate centrally mediated anti-nociception which, in the case of the hot plate test, was pentylenetetrazole (PTZ) and naloxone reversible, implicating GABAergic and opioidergic mechanisms. CHD was also effective against both the neurogenic and inflammatory mediator phases induced in the formalin test and it also disclosed anti-inflammatory activity against the phlogistic agents, carrageenan, serotonin, histamine and xylene compared with standard drugs in edema volume tests. In silico studies indicated that CHD possessed preferential affinity for GABAA, opioid and COX-2 target sites and this was supported by molecular dynamic simulations where computation of free energy of binding also favored the formation of stable complexes with these sites. These findings suggest that CHD has prospective anti-nociceptive and anti-inflammatory properties, probably mediated through GABAergic and opioidergic interactions supplemented by COX-2 and 5-LOX enzyme inhibition in addition to reducing pro-inflammatory cytokine expression. CHD may therefore possess potentially beneficial therapeutic effectiveness in the management of inflammation and pain.

Febuxostat-based amides and some derived heterocycles targeting xanthine oxidase and COX inhibition. Synthesis, in vitro and in vivo biological evaluation, molecular modeling and in silico ADMET studies

Various febuxostat derivatives comprising carboxamide functionalities and different substituted heterocycles were synthesized and evaluated for their biological activities as xanthine oxidase (XO) and cyclooxygenase (COX) inhibitors. All the tested compounds exhibited variable in vitro XO inhibitory activities (IC₅₀ values 0.009-0.077 µM), among which the analog 17 has emerged as the most potent derivative (IC₅₀ 0.009 µM), representing nearly 3-times the potency of febuxostat (IC₅₀ 0.026 µM). The same analogs were further investigated for their in vitro COX-1 and COX-2 inhibitory activity, where fifteen analogs demonstrated recognizable COX-2 inhibitory potential (IC₅₀ values range 0.04 - 0.1 µM), when correlated with celecoxib (IC₅₀ 0.05 µM), together with appreciable selectivity indices. Compounds 5a, 14b, 17, 19c, 19e and 21b that showed significant in vitro XO and/ or COX inhibitory potentials were further investigated for their in vivo hypouricemic as well as anti-inflammatory activities. Interestingly, the in vivo results were concordant with the collected in vitro data. Docking of compounds 5a, 14b, 17, 19c, 19e and 21b with the active sites of XO and COX-2 isozymes demonstrated superior binding profile compared with the reported ligands (febuxostat and celecoxib, respectively). Their docking scores were reasonable and cohering to a great extent with their corresponding in vitro IC₅₀ values. Moreover, in silico computation of the predicted pharmacokinetic and toxicity properties (ADMET), together with the ligand efficiency (LE) of the same six compounds suggesting their liability to act as new orally active drug candidates with a predicted high safety profile.

Design, synthesis and molecular docking of new pyrazole-thiazolidinones as potent anti-inflammatory and analgesic agents with TNF-α inhibitory activity

A new set of derivatives bearing pyrazole-methylenehydrazono-thiazolidinone scaffold 4-23 was designed, synthesized and confirmed by different spectroscopic means and elemental analyses. In-vivo anti-inflammatory and ulcerogenic evaluation was performed for all the newly synthesized derivatives using indomethacin, celecoxib and diclofenac as standard drugs. The compounds 5, 10, 15, 17, 21, 22 appeared to be the most promising candidates producing rapid onset and long duration of anti-inflammatory activity as well as promising GIT safety profile. Furthermore, analgesic evaluation revealed that the compounds 5, 10, 15 and 22 produced potent and long acting analgesia accompanied with significant inhibition of the inflammatory cytokine TNF-α level in comparison with the standard drugs. Molecular docking study of the latter derivatives was also carried out to rationalize their binding affinities and their modes of interactions with the active site of TNF-α.

Oxidative Stress and Inflammation in Renal and Cardiovascular Complications of Diabetes

Simple Summary

The progressive nature of type 2 diabetes mellitus (T2DM) leads to micro- and macro-vascular complications, including renal and cardiovascular disease. These alone, or in combination, are a major cause of premature morbidity and mortality in diabetic patients. Despite advances in glucose lowering treatments, these diabetic complications are still inadequately prevented or reversed. This ongoing cardiovascular–renal burden in diabetes poses a heavy cost on the health care system. Therefore, there is an urgent need to develop more effective treatments. In this review, we discuss how oxidative stress and inflammation induce and perpetuate the renal and cardiovascular complications of diabetes. It is particularly important to understand these driving mechanisms in order to elucidate pharmacological targets and mechanism-based future drug therapies.

Abstract

Oxidative stress and inflammation are considered major drivers in the pathogenesis of diabetic complications, including renal and cardiovascular disease. A symbiotic relationship also appears to exist between oxidative stress and inflammation. Several emerging therapies target these crucial pathways, to alleviate the burden of the aforementioned diseases. Oxidative stress refers to an imbalance between reactive oxygen species (ROS) and antioxidant defenses, a pathological state which not only leads to direct cellular damage but also an inflammatory cascade that further perpetuates tissue injury. Emerging therapeutic strategies tackle these pathways in a variety of ways, from increasing antioxidant defenses (antioxidants and Nrf2 activators) to reducing ROS production (NADPH oxidase inhibitors and XO inhibitors) or inhibiting the associated inflammatory pathways (NLRP3 inflammasome inhibitors, lipoxins, GLP-1 receptor agonists, and AT-1 receptor antagonists). This review summarizes the mechanisms by which oxidative stress and inflammation contribute to and perpetuate diabetes associated renal and cardiovascular disease along with the therapeutic strategies which target these pathways to provide reno and cardiovascular protection in the setting of diabetes.

Astragalin attenuates oxidative stress and acute inflammatory responses in carrageenan-induced paw edema in mice

Astragalin is a flavonoid existed in several edible and medicinal plants and was recorded to have multiple biological and pharmacological significances. This work aimed to assess the possible protective effect of astragalin administration against oxidative tension, acute inflammation and histopathological deformations in a mouse paw edema model induced following intra sub-plantar injection of carrageenan. Thirty-six male Swiss mice were divided into four groups: control, carrageenan, astragalin (75 mg/kg) + carrageenan, and indomethacin (10 mg/kg) + carrageenan. Astragalin administration for five consecutive days to carrageenan injected mice showed a significant reduction in the development of paw in a time dependent effect, inhibited lipoperoxidation by-product, malondialdehyde and increased superoxide dismutase and catalase activities. Astragalin was found also to suppress the inflammatory signaling in the inflamed tissue as exhibited by the decreased myeloperoxidase activity along with the decreased protein and transcriptional level of pro-inflammatory cytokines including tumor necrosis factor-alpha, interleukin-1 beta and interleukin-6. Moreover, inducible nitric oxide synthase and cyclooxygenase-2 expressions and their products (nitric oxide and prostaglandin E2) were downregulated. Additionally, astragalin decreased monocyte chemoattractant protein-1 and nuclear factor kappa B expression in the inflamed paw tissue. The recorded findings provide evidences for the potential application of astragalin as a plant-derived remedy for the treatment of acute inflammation due to its promising antioxidant and anti-inflammatory activities along with its ameliorative impact against the histopathological changes in the paw tissue.

Green Coffea arabica Extract Ameliorates Testicular Injury in High-Fat Diet/Streptozotocin-Induced Diabetes in Rats

Diabetes mellitus (DM) is a chronic endocrine disease characterized by persistent hyperglycemia. Oxidative damage, inflammatory cytokines, and apoptotic cell death play a major role in the induction and progression of male testicular damage. Plant-derived phytochemicals such as green coffee (Coffea arabica) can possess antidiabetic effects with little toxicity. The current study is aimed at investigating the therapeutic roles of green coffee in diabetic testicular injury stimulated by high-fat diet/streptozotocin administration. Diabetes mellitus was induced by a high-fat diet and a single dose of streptozotocin (STZ) (35 mg kg-1) in male albino rats. Diabetic animals were orally given two different concentrations of green coffee (50 mg kg-1 and 100 mg kg-1) for 28 days. The levels of testosterone, luteinizing hormone, and follicle-stimulating hormone and parameters of oxidative stress, inflammation, and apoptosis were measured. mRNAs and protein levels were detected quantitatively by real-time PCR and ELISA, respectively. In the diabetic group, the levels of testosterone, luteinizing hormone, and follicle-stimulating hormone showed a significant reduction while they increased significantly after green coffee treatment. A significant increase of antioxidant markers glutathione, superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase along with decreased levels of lipid peroxides and nitric oxide was observed after green coffee treatment in the diabetic group. Finally, the levels of IL-1β, TNF-α, Bax, and caspase-3 were also decreased in both treated groups (metformin and green coffee) when compared to the diabetic group. We conclude that testicular oxidative impairment induced by a high-fat diet (HFD) and STZ can be reversed by green coffee. Administration of green coffee could represent a promising therapeutic agent which can help the treatment of type 2 DM-induced testicular dysfunction.

Luteolin protects against testicular injury induced by lead acetate by activating the Nrf2/HO-1 pathway

Lead (Pb) is a toxic heavy metal that is harmful to humans, especially male reproductive organs. Luteolin (LUT) is a naturally occurring flavonoid with numerous biological activities. Our aim was to investigate the possible reproprotective effect of LUT against testicular deficits induced by Pb intoxication. In the present study, 28 rats were distributed into 4 groups: control, LUT (50 mg/kg), lead acetate (PbAc, 20 mg/kg), and LUT + PbAc groups, in which rats were pre-treated with LUT 3 hr before PbAc injection. All animals were treated for 7 days. Oxidative stress, inflammatory and apoptotic markers along with histopathological changes have been examined using spectrophotometric, ELISA, real-time PCR, and histopathological methods. PbAc injection elevated Pb concentration in testicular tissue and decreased levels of sex hormones. PbAc intoxication exacerbated lipoperoxidation and nitric oxide formation, depleted superoxide dismutase, and catalase activities along with glutathione and its originated enzymes (glutathione peroxidase and glutathione reductase). At the molecular level, PbAc deactivated nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 in the testicular tissue. In addition, PbAc toxicity induced inflammatory and apoptotic cascades in testicular tissue as evidenced by the increased tumor necrosis factor-alpha, interleukin-1 beta, inducible nitric oxide synthase, Bax, and caspase 3, while Bcl-2 was declined. Histopathological examination of testicular tissue also revealed that PbAc caused degeneration alterations in spermatogenic cells, the spermatogenic epithelial cells were disconnected from the basement membrane, and the seminiferous tubules were vacuolated. Remarkably, pre-treatment with LUT minimized significantly the testicular damage induced by PbAc. Therefore, we conclude that LUT may have a beneficial effect against PbAc-induced testicular injury through preventing oxidative challenge, inflammation, and finally apoptosis.

Diallyl Disulfide Suppresses Inflammatory and Oxidative Machineries following Carrageenan Injection-Induced Paw Edema in Mice

Diallyl disulfide (DADS) is the major organosulfur constituent in garlic, with a variety of pharmacological activities including antioxidant and anti-inflammatory. Here, we examined the potential antiedematous impact of DADS- versus carrageenan-mediated paw edema in mice. Carrageenan injection potentiated an inflammatory reaction as presented by the elevated serological C-reactive protein (CRP) levels and transcription of tumor necrosis factor-alpha (TNF-α, Tnfα), interleukin-1 beta (IL-1β, Il1b), interleukin-2 (IL-2, Il2), inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase-2 (COX-2, Ptgs2), prostaglandin E2 (PGE2), monocyte chemoattractant protein-1 (MCP-1, Ccl1), nuclear factor kappa B (NF-κB), and myeloperoxidase (MPO) activity, while interleukin-10 (IL-10) was declined in the injured paw tissue. Additionally, carrageenan elevated lipid peroxidation in terms of malondialdehyde (MDA) and decreased glutathione content (GSH). Remarkably, DADS was found to inhibit the inflammatory signaling, suppressed the developed oxidative damage, and protected the histopathological alterations in the inflamed paw tissue in response to carrageenan injection. Our findings suggest that DADS could be used as an alternative therapy used to alleviate the pathophysiological changes associated with the genesis of paw edema through its potent anti-inflammatory and antioxidant impacts.