Management of ulcerative colitis by dichloroacetate: Impact on NFATC1/NLRP3/IL1B signaling based on bioinformatics analysis combined with in vivo experimental verification.

The inflammatory response in ulcerative colitis (UC) could be relieved by the conventional immunomodulatory agents; 5-aminosalicylic acid, corticosteroids, or azathioprine. However, the low remission rates and the intolerance to these agents necessitate investigation of gene expression signature in UC that could influence the therapeutic efficacy of drugs, as well as the interference with persistence genes by novel therapeutic option. Three microarray datasets (GSE66407, GSE38713 and GSE14580) from the NCBI-GEO database were utilized. Differentially expressed genes between samples of patients with UC and healthy ones were analyzed using R software. In addition, in vivo study using oxazolone-induced UC in BALB/c mice was carried out to investigate the proposed therapeutic efficacy of dichloroacetate (DCA). The bioinformatics analysis revealed the persistence of NLRP3, NFATC1, and IL1B in UC despite treatment with common therapeutic agents. DCA administration to oxazolone-treated mice showed remarkable interference with those persistence genes. Western blotting analysis for NLRP3, NFATC1, nuclear/total NF-κB, and cleaved caspase-1 revealed the ability of DCA to reduce the expression levels of these proteins in oxazolone-treated mice. Additionally, the inflammatory cytokines IL-1ß and IL-13 were reduced in colonic tissue by DCA treatment. The therapeutic efficacy of DCA was further confirmed by the apparent reduction in histopathological scoring, disease activity index, and the normalization of colon length. Therefore, DCA could be suggested as a novel and promising therapeutic option in UC based on its ability to interfere with the persistence of NFATC1/NLRP3/IL1B signaling. That merits further safety/toxicological pre-clinical assessment and update of bioavailability/metabolism data prior to clinical investigation.

Balancing renal Ang-II/Ang-(1-7) by xanthenone; an ACE2 activator; contributes to the attenuation of Ang-II/p38 MAPK/NF-κB p65 and Bax/caspase-3 pathways in amphotericin B-induced nephrotoxicity in rats.

Despite the great importance of amphotericin B for the management of life-threatening systemic fungal infections, its nephrotoxic effect restricts its repeated administration. This study was designed to examine the prospective modulatory effects of xanthenone, an ACE2 activator, against amphotericin B nephrotoxicity. Male Wistar rats were allocated into four groups; control (1st), Xanthenone (2nd), Amphotericin B (3rd), and Xanthenone + Amphotericin B (4th). The second and fourth groups received xanthenone (2 mg/kg; s.c.) daily for 14 consecutive days. Amphotericin B (18.5 mg/kg; i.p.) was administered to the third and fourth groups daily starting from day 8. After 2 weeks, samples were withdrawn for analysis. The histopathological findings, molecular and biochemical markers showed that amphotericin B caused marked renal injury. Pretreatment with xanthenone ameliorated amphotericin B-induced deterioration in kidney function biomarkers (creatinine, urea, cystatin C, KIM-1) and guarded against the disturbance of serum electrolytes (Na+, K+, Mg2+) due to amphotericin B-induced tubular dysfunction. Besides, the ACE2 activator xanthenone-balanced renal Ang-II/Ang-(1-7), and so the inflammatory signaling p38 MAPK/NF-κB p65 and its downstream inflammatory cytokines (TNF-α, IL-6) were attenuated. Meanwhile, the anti-oxidant signaling Nrf2/HO-1 and glutathione content were preserved, but the lipid peroxidation marker MDA was declined. These regulatory effects of xanthenone eventually enhanced Bcl-2 (anti-apoptotic), but reduced Bax (pro-apoptotic) and cleaved caspase-3 (apoptotic executioner) protein expressions. Collectively, the regulatory effects of xanthenone on renal Ang-II/Ang-(1-7) could at least partially contribute to the mitigation of amphotericin B nephrotoxicity by attenuating inflammatory signaling, oxidative stress, and apoptosis, thus improving the tolerability to amphotericin B.

Renoprotective effect of vinpocetine against ischemia/reperfusion injury: Modulation of NADPH oxidase/Nrf2, IKKß/NF-κB p65, and cleaved caspase-3 expressions.

Ischemia/reperfusion injury (IRI) during kidney transplantation is a serious clinical problem with a high mortality rate and a lack of therapy. Therefore, there is a need to improve the ability of the kidney to tolerate IRI during transplantation. This study aimed to investigate the possible protective effect of vinpocetine; a derivative of vincamine alkaloid; against renal IRI in rats with the elucidation of the involved mechanisms. Vinpocetine (25 mg/kg; i.p.) was administered for 10 successive days before the induction of ischemia by bilateral clamping of both renal pedicles for 45 min followed by 24 h of reperfusion. Blood and renal tissue samples were then collected for biochemical, molecular, and histopathological investigations. Vinpocetine significantly reduced serum creatinine and blood urea nitrogen levels in rats subjected to IRI. It also reduced mRNA expression of NADPH oxidase and renal content of malondialdehyde, while enhanced Nrf2 protein expression and renal content of reduced glutathione. The suppression of the provoked inflammatory response was evident by the downregulation of IKKß and NF-κB p65 protein expressions, as well as their downstream inflammatory markers; tumor necrosis factor-α, interleukin-6, and myeloperoxidase. In addition, vinpocetine reduced protein expression of the apoptotic executioner cleaved caspase-3. These nephroprotective effects were confirmed by the improvement in histopathological features. Collectively, the protective effect of vinpocetine against IRI could be attributed to modulation of NADPH oxidase/Nrf2, IKKß/NF-κB p65, and cleaved caspase-3 expressions. Thus, vinpocetine could improve oxidant/antioxidant balance, suppress triggered inflammatory response, and promote renal cell survival after IRI.

Interference with megalin expression/endocytic function by montelukast mitigates gentamicin nephrotoxicity: Downregulation of ClC-5 expression.

Megalin receptor-mediated endocytosis participates a crucial role in gentamicin (GM) uptake, accumulation, and toxicity. In this study, we investigated the potential effects of montelukast (MLK) on megalin expression/endocytic function against GM nephrotoxicity. Male Wistar rats were administered GM (120 mg/kg; i.p.) daily in divided doses along 4 hr; 30 mg/kg/hr; for 7 days. MLK (30 mg/kg/day) was orally administered 7 days before and then concurrently with GM. The protein expressions of megalin and chloride channel-5 (ClC-5); one of the essential regulators of megalin endocytic function; were determined by Western blotting. Besides, the endocytic function of megalin was evaluated by the uptake of bovine serum albumin labeled with fluorescein isothiocyanate (FITC-BSA) into proximal tubular epithelial cells. Moreover, kidney function biomarkers (Cr, BUN, GFR, KIM-1, cystatin-C) and apoptosis markers (p-AKT1, cleaved caspase-3) were estimated. Co-treatment with MLK downregulated ClC-5 expression leading to reduced recycling of megalin to the plasma membrane, reduced expression, and so impaired endocytic function that was evidenced by reduced uptake of FITC-BSA in proximal tubular epithelial cells. The protein expression of the apoptotic executioner cleaved caspase-3 was significantly reduced, while that of the antiapoptotic p-AKT1 was elevated. These results were confirmed by the improvement of kidney functions and histological findings. Our data suggest that MLK could interfere with megalin expression/endocytic function that could be attributed to downregulation of ClC-5 protein expression. That eventually reduces renal cell apoptosis and improves kidney functions after GM administration without affecting the antibacterial activity of GM. Therefore, reduced expression of ClC-5 and interference with megalin expression/endocytic function by MLK could be an effective strategy against GM nephrotoxicity.

The modulatory effects of cinnamaldehyde on uric acid level and IL-6/JAK1/STAT3 signaling as a promising therapeutic strategy against benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) is a widespread disorder in elderly men. Cinnamaldehyde, which is a major constituent in the essential oil of cinnamon, has been previously reported to reduce xanthine oxidase activity, in addition to its anti-inflammatory, anti-oxidant, and anti-proliferative activities. Our study was designed to investigate the potential modulatory effects of cinnamaldehyde on testosterone model of BPH in rats through reduction of uric acid level, and suppression of IL-6/JAK1/STAT3 signaling pathway. Cinnamaldehyde (40 and 75 mg/kg) was orally administered to male Wistar rats for 3 weeks, and concurrently with testosterone (3 mg/kg, s.c.) from the second week. Cinnamaldehyde ameliorated the elevation in prostatic weight and index compared to rats treated with testosterone only, that was also confirmed by alleviation of histopathological changes in prostate architecture. The protective mechanisms of cinnamaldehyde were elucidated through inhibition of xanthine oxidase activity and reduced uric acid level. That was accompanied by reduction of the pro-inflammatory cytokines; interleukin-6 (IL-6), IL-1ß, tumor necrosis factor-alpha (TNF-α), and the nuclear translocation of the transcription factor NF-κB p65, that could be attributed also to the enhanced anti-oxidant defense by cinnamaldehyde. The protein expression of JAK1, which is IL-6 receptor linked protein, was reduced with subsequently reduced activation of STAT3 protein. That eventually suppressed the formation of the proliferation protein cyclin D1, while elevated Bax/Bcl2 ratio. It can be concluded that reducing uric acid level through xanthine oxidase inhibition and suppression of the inflammatory signaling cascade; IL-6/JAK1/STAT3; by cinnamaldehyde could be a novel and promising therapeutic approach against BPH.

Aliskiren, tadalafil, and cinnamaldehyde alleviate joint destruction biomarkers; MMP-3 and RANKL; in complete Freund's adjuvant arthritis model: Downregulation of IL-6/JAK2/STAT3 signaling pathway.

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease, which is accompanied by progressive joint damage and disability. The intolerability of conventional antirheumatic drugs by some patients necessitates the search for effective antirheumatic agents having better tolerability. In the current work, we aimed to investigate the efficacy of cinnamaldehyde, tadalafil, and aliskiren as potential antirheumatic candidates and to explore their modulatory effects on joint destruction, inflammatory response, and intracellular signaling. Arthritis was induced in female Wistar rats by complete Freund's adjuvant (CFA) 0.4 ml s.c. on days 1, 4, and 7. Treated groups received their respective drugs, starting from day 13, daily for 3 weeks. Methotrexate and prednisolone were the standard antirheumatic drugs, while cinnamaldehyde, tadalafil, and aliskiren were the test agents. Treatment with cinnamaldehyde, tadalafil, or aliskiren reduced serum levels of rheumatoid factor, and pro-inflammatory cytokines; tumor necrosis factor-alpha and interleukin-6 (IL-6), along with elevated level of IL-10 which is an anti-inflammatory cytokine. Besides, cartilage and bone destruction biomarkers; matrix metalloproteinase-3 (MMP-3) and receptor activator of nuclear factor-kappa B ligand (RANKL); were significantly reduced after treatment with the test agents, which was further confirmed by histopathological investigation. The elevated protein expressions of phosphorylated-Janus kinase 2 (p-JAK2), phosphorylated-signal transducer and activator of transcription 3 (p-STAT3), and inducible nitric oxide synthase (iNOS) in articular tissue were markedly attenuated after treatment with cinnamaldehyde, tadalafil, or aliskiren, while that of endothelial nitric oxide synthase (eNOS) was greatly enhanced. In addition, oxidative stress and inflammatory markers such as malondialdehyde, nitric oxide, and myeloperoxidase were reduced in joint tissue after treatment with the test agents, while glutathione content was elevated. Furthermore, the renin inhibitor aliskiren produced effects close to those of the normal and methotrexate, the gold standard antirheumatic drug, in most of the measured parameters. Collectively, these findings led to the assumption that the downregulation of IL-6/JAK2/STAT3 signaling by cinnamaldehyde, tadalafil, and aliskiren could alleviate joint destruction by MMP-3 and RANKL, reduce iNOS, and enhance eNOS expressions. Moreover, aliskiren could be a promising therapeutic agent for RA, because of its ability to normalize most of the measured parameters after CFA-induced arthritis.

Amlodipine alleviates cisplatin-induced nephrotoxicity in rats through gamma-glutamyl transpeptidase (GGT) enzyme inhibition, associated with regulation of Nrf2/HO-1, MAPK/NF-κB, and Bax/Bcl-2 signaling.

BACKGROUND: The therapeutic utility of the effective chemotherapeutic agent cisplatin is hampered by its nephrotoxic effect. We aimed from the current study to examine the possible protective effects of amlodipine through gamma-glutamyl transpeptidase (GGT) enzyme inhibition against cisplatin nephrotoxicity. METHODS: Amlodipine (5 mg/kg, po) was administered to rats for 14 successive days. On the 10th day, nephrotoxicity was induced by a single dose of cisplatin (6.5 mg/kg, ip). On the last day, blood samples were collected for estimation of kidney function, while kidney samples were used for determination of GGT activity, oxidative stress, inflammatory, and apoptotic markers, along with histopathological evaluation. RESULTS: Amlodipine alleviated renal injury that was manifested by significantly diminished serum creatinine and blood urea nitrogen levels, compared to cisplatin group. Amlodipine inhibited GGT enzyme, which participates in the metabolism of extracellular glutathione (GSH) and platinum-GSH-conjugates to a reactive toxic thiol. Besides, amlodipine diminished mRNA expression of NADPH oxidase in the kidney, while enhanced the anti-oxidant defense by activating Nrf2/HO-1 signaling. Additionally, it showed marked anti-inflammatory response by reducing expressions of p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-κB), with subsequent down-regulation of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and vascular cell adhesion molecule-1 (VCAM-1). Moreover, amlodipine reduced Bax/Bcl-2 ratio and elevated hepatocyte growth factor (HGF), thus favoring renal cell survival. CONCLUSIONS: Effective GGT inhibition by amlodipine associated with enhancement of anti-oxidant defense and suppression of inflammatory signaling and apoptosis support our suggestion that amlodipine could replace toxic GGT inhibitors in protection against cisplatin nephrotoxicity.

Selective cyclooxygenase inhibition and ulcerogenic liability of some newly prepared anti-inflammatory agents having thiazolo[4,5-d]pyrimidine scaffold.

Novel candidates of thiazolo[4,5-d]pyrimidines (9a-l) were synthesized and their structures were elucidated by spectral and elemental analyses. All the novel derivatives were screened for their cyclooxygenase inhibitory effect, anti-inflammatory activity and ulcerogenic liability. All the new compounds exhibited anti-inflammatory activity, especially 1-(4-[7-(4-nitrophenyl)-5-thioxo-5,6-dihydro-3H-thiazolo[4,5-d]pyrimidin-2-ylideneamino]phenyl)ethanone (9g) was the most active derivative with 57%, 88% and 88% inhibition of inflammation after 1, 3 and 5h, respectively. Furthermore, this derivative 9g recorded higher anti-inflammatory activity than celecoxib which showed 43%, 43% and 54% inhibition after 1, 3 and 5h, sequentially. Moreover, the target derivatives 9a-l demonstrated moderate to high potent inhibitory action towards COX-2 (IC50 = 0.87-3.78 µM), in particular, the derivatives 9e (IC50 = 0.92 µM), 9g (IC50 = 0.87 µM) and 9k (IC50 = 1.02 µM) recorded higher COX-2 inhibitory effect than the selective COX-2 inhibitor drug celecoxib (IC50 = 1.11 µM). The in vivo potent compounds (9e, 9g and 9k) caused variable ulceration effect (ulcer index = 5-12.25) in comparison to that of celecoxib (ulcer index = 3). Molecular docking was performed to the most potent COX-2 inhibitors (9e, 9g and 9k) to explore the binding mode of these derivatives with Cyclooxygenase-2 enzyme.

Novel pyrimidine-pyridine hybrids: Synthesis, cyclooxygenase inhibition, anti-inflammatory activity and ulcerogenic liability.

Some derivatives containing pyrido[2,3-d:6,5d']dipyrimidine-4,5-diones (9a-f), tetrahydropyrido[2,3-d]pyrimidine-6-carbonitriles (11a-c) and 6-(4-acetylphenyl)-2-thioxo-2,3,5,6,7,8-hexahydro-1H-pyrimido[4,5-d]pyrimidin-4-one (12) were synthesized from 6-amino-2-thioxo-2,3-dihydro-1H-pyrimidin-4-one (8). The anti-inflammatory effect of these candidates was determined and the ulcer indices were calculated for active compounds. 7-Amino-5-(3,4,5-trimethoxyphenyl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrido[2,3-d] pyrimidine-6-carbonitrile (11c) exhibited better edema inhibition than celecoxib. Moreover, compounds 9b, 9d and 11c revealed better COX-2 inhibitory activity in a range (IC50 = 0.25-0.89 µM) than celecoxib (IC50 = 1.11 µM). Regarding ulcerogenic liability, all of the compounds under the study were less ulcerogenic than indomethacin. Molecular docking studies had been carried on active candidates 9d and 11c to explore action mode of these candidates as leads for discovering other anti-inflammatory agents.

Design, synthesis, analgesic, anti-inflammatory activity of novel pyrazolones possessing aminosulfonyl pharmacophore as inhibitors of COX-2/5-LOX enzymes: Histopathological and docking studies.

A series of newly synthesized 4-aryl-hydrazonopyrazolones were designed and their structures were confirmed by spectral and elemental analyses. All synthesized compounds were evaluated for their in vitro COXs, 5-LOX inhibition, in vivo analgesic and anti-inflammatory activities. Compounds 5d, 5f and 5i were found to be the most potent COX-2/5-LOX inhibitors with superior COX-2 selectivity index values (SI = 5.29-5.69) to reference standard celecoxib (SI = 3.52). Four compounds; 5b, 5c, 5d and 5f showed excellent anti-inflammatory activity (% edema inhibition = 72.72-54.54%) and perfect ED50 values (ED50 = 0.044-0.104 mmol/kg) relative to celecoxib (ED50 = 0.032 mmol/kg). To explore the most active compounds, ulcerogenic effect on stomach in comparison with indomethacin and celecoxib in addition to histopathological investigations were performed. Compound 5f showed better gastric profile (UI = 2.33) than celecoxib (UI = 3.00). Also, 5f caused 50% increase in thermal pain threshold close to reference drug indomethacin (53.13%). Docking study of all the target compounds into COX-2 and 5-LOX active sites was performed to rational their anti-inflammatory activities.

Synthesis and biological evaluations of new nitric oxide-anti-inflammatory drug hybrids.

Three novel series of nitroso derivatives (11-15), isoxazolopyrazoles (17a-c) and isoxazolo[3,4-d]pyridazines (18a-c) were prepared from the hydroxyimoyl chloride 10. In vitro COX1⧹2 inhibition activities were evaluated, both of 17b and 18a proved a promising inhibitory activity with IC50=1.12, 0.78µM in sequent. Carrageenan induced Paw edema, ulcer liability, nitric oxide (NO) release and histopathological study were determined. Most of the prepared compounds showed excellent activities. Reactions of 2-aminopyridine and enaminone with hydroxyimoyl chloride 10 were investigated and proved by 2D NMR. Molecular docking for most active compounds was operated giving a hint for compound-receptor interactions.

Novel tetrazole and cyanamide derivatives as inhibitors of cyclooxygenase-2 enzyme: design, synthesis, anti-inflammatory evaluation, ulcerogenic liability and docking study.

Nineteen new compounds containing tetrazole and/or cyanamide moiety have been designed and synthesised. Their structures were confirmed using spectroscopic methods and elemental analyses. Anti-inflammatory activity for all the synthesised compounds was evaluated in vivo. The most active compounds 4c, 5a, 5d-f, 8a and b and 9a and b were further investigated for their ulcerogenic liability and analgesic activity. Pyrazoline derivatives 9b and 8b bearing trimethoxyphenyl part and SO2NH2 or SO2Me pharmacophore showed equal or nearly the same ulcerogenic liability (UI: 0.5, 0.75, respectively), to celecoxib (UI: 0.50). Most of tested compounds showed potent central and/or peripheral analgesic activities. Histopathological investigations were done to evaluate test compounds effect on rat's gastric tissue. The obtained results were in consistent with the in vitro data on COX evaluation. Docking study was also done for all the target compounds inside COX-2-active site.

Synthesis, cyclooxygenase inhibition, anti-inflammatory evaluation and ulcerogenic liability of new 1-phenylpyrazolo[3,4-d]pyrimidine derivatives.

A new group of 1-phenylpyrazolo[3,4-d]pyrimidine derivatives 14a-d-21 were synthesized from 2-(6-methyl-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4-yloxy)acetohydrazide (12). All the synthesized compounds were evaluated for their cyclooxygenase (COX) inhibition, anti-inflammatory activity and ulcerogenic liability. All the target compounds were more potential in inhibiting COX-2 than COX-1. Compounds having pyrazolyl moiety in a hybrid structure with pyrazolo[3,4-d]pyrimidine scaffold (14a-d, 16 and 17) showed higher edema inhibition percentage activities (34-68%) and the 5-aminopyrazole derivative (14c, ED50 = 87.9 µmol/kg) was the most potent one > celecoxib (ED50 = 91.9 µmol/kg). While, the in vivo potent compounds (14a-d, 16, 17 and 21) caused variable ulceration effect (ulcer index = 0.33-4.0) comparable to that of celecoxib (ulcer index = 0.33), the pyrazol-3-one derivative (16) and the acetohydrazide (21) were the least ulcerogenic derivatives showing the same ulcerogenic potential of celecoxib.

Synthesis, Cyclooxygenase Inhibition, Anti-Inflammatory Evaluation, and Ulcerogenic Liability of New 1,3,5-Triarylpyrazoline Derivatives Possessing a Methanesulfonyl Pharmacophore.

A new series of 1,3,5-triarylpyrazolines 13a-l was synthesized and all prepared compounds were evaluated for their in vitro COX-1/COX-2 inhibitory activity and in vivo anti-inflammatory activity. All test compounds were more selective for the COX-2 isozyme and showed good in vivo anti-inflammatory activity. Compound 13h was the most COX-2 selective compound (COX-2 selectivity index (SI) = 10.23) and the most potent anti-inflammatory derivative (ED50 = 60.1 µmol/kg) in comparison with celecoxib (COX-2 SI = 9.29 and ED50 = 81.4 µmol/kg). All screened compounds were less ulcerogenic (ulcer indexes (UI) = 0.33-1.33) than aspirin (UI = 2.33) and comparable to celecoxib (UI = 0.33).

The enteroprotective effect of nifuroxazide against methotrexate-induced intestinal injury involves co-activation of PPAR-γ, SIRT1, Nrf2, and suppression of NF-κB and JAK1/STAT3 signals.

Methotrexate (MTX) has long manifested therapeutic efficacy in several neoplastic and autoimmune disorders. However, MTX-associated intestinal toxicity restricts the continuation of treatment. Nifuroxazide (NIF) is an oral antibiotic approved for gastrointestinal infections as an effective antidiarrheal agent with a high safety profile. The current study was designed to explore the potential efficacy of NIF in alleviating intestinal toxicity associated with MTX chemotherapy with the elucidation of the proposed molecular mechanisms. Rats were administered NIF (50 mg/kg; p.o.) for ten days. On day five, a single i.p. injection of MTX (20 mg/kg) was given to induce intestinal intoxication. At the end of the experiment, duodenal tissue samples were isolated for biochemical, Western blotting, immunohistochemical (IHC), and histopathological analysis via H&E, PSA, and Alcian blue stains. NIF showed antioxidant enteroprotective effects against MTX intestinal intoxication through enhanced expression of the redox-sensitive signals of PPAR-γ, SIRT1, and Nrf2 estimated by IHC. Moreover, NIF down-regulated the pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6), NF-κB protein expression, and the phosphorylation of JAK1/STAT3 proteins, leading to mitigation of intestinal inflammation. In accordance, the histological investigation revealed that NIF ameliorated the intestinal pathological changes, preserved the goblet cells, and reduced the inflammatory cells infiltration. Therefore, NIF could be a promising candidate for adjunctive therapy with MTX to mitigate the associated intestinal injury and increase its tolerability.

Enhanced eNOS/nitric oxide production by nebivolol interferes with TGF-ß1/Smad3 signaling and collagen I deposition in the kidney after prolonged tacrolimus administration.

AIMS: Tacrolimus is an effective immunosuppressant commonly used post-transplantation and in certain autoimmune diseases. However, its long-term administration is associated with renal fibrosis through transforming growth factor-beta/suppressor of mother against decapentaplegic (TGF-ß/Smad) signaling that could be partly attributed to endothelial dysfunction alongside decreased nitric oxide (NO) release. Our study aimed to investigate the prospective renal anti-fibrotic effect of enhanced NO production by nebivolol against tacrolimus-stimulated TGF-ß1/Smad3 signaling. MATERIALS AND METHODS: To illustrate the proposed mechanism of nebivolol, Nω-nitro-L-arginine methyl ester (L-NAME); nitric oxide synthase inhibitor; was co-administered with nebivolol. Rats were treated for 30 days as control, tacrolimus, tacrolimus/nebivolol, tacrolimus/L-NAME, and tacrolimus/nebivolol/L-NAME groups. KEY FINDINGS: Our results revealed that renal NO content was reduced in tacrolimus-treated rats, while treatment with tacrolimus/nebivolol enhanced NO content via up-regulated endothelial nitric oxide synthase (eNOS), but down-regulated inducible nitric oxide synthase (iNOS) expression. That participated in the inhibition of TGF-ß1/Smad3 signaling induced by tacrolimus, where the addition of L-NAME abolished the defensive effects of nebivolol. Subsequently, the deposition of collagen I and alpha-smooth muscle actin (α-SMA) was retarded by nebivolol, emphasized by reduced Masson's trichrome staining. In accordance, there was a strong negative correlation between eNOS and both TGF-ß1 and collagen I protein expression. The protective effects of nebivolol were further confirmed by the improvement in kidney function biomarkers and histological features. SIGNIFICANCE: It can be suggested that treatment with nebivolol along with tacrolimus could effectively suppress renal TGF-ß1/Smad3 fibrotic signaling via the enhancement of endothelial NO production, thus curbing renal fibrosis development.

Investigating the tamoxifen/high-fat diet synergy: a promising paradigm for nonalcoholic steatohepatitis induction in a rat model.

Non-alcoholic steatohepatitis (NASH) is a severe liver condition characterized by excessive fat deposition, ballooning, and lobular inflammation. This investigation was conducted to estimate the capability of concomitant tamoxifen administration (TAM) with a high fat diet (HFD) to induce a reliable NASH model that mimics human NASH features. Rats were administered TAM (25 mg/kg/day p.o.) and consumed HFD for 5 weeks. A time-course investigation was conducted to determine the optimal time for NASH development. Liver function indices, hepatic lipid profile factors, oxidative stress biomarkers, and inflammatory mediators were estimated. Additionally, macroscopic and microscopic changes were examined. Compared with the time-matched control group receiving vehicle alone, TAM/HFD significantly impaired liver function indices represented as marked elevation in ALT, AST, and ALP serum levels. TAM/HFD significantly increased lipid profile factors including high TG and TC hepatic levels. Additionally, TAM/HFD remarkably raised hepatic levels of TNF-α and IL-17 and significantly decreased IL-10. The combination also increases the oxidative status evidenced by high content of MDA as well as low activity of GPx and SOD. Accordingly, the combination of TAM and HFD for 5 weeks collaboratively promotes NASH development by initiating compromised hepatocyte functionality, elevated lipid levels, oxidative stress, and liver inflammation.

Lysosomal membrane stabilization by imipramine attenuates gentamicin-induced renal injury: Enhanced LAMP2 expression, down-regulation of cytoplasmic cathepsin D and tBid/cytochrome c/cleaved caspase-3 apoptotic signaling.

Nephrotoxicity is a serious complication commonly encountered with gentamicin (GTM) treatment. Permeabilization of lysosomes with subsequent cytoplasmic release of GTM and cathepsins is considered a crucial issue in progression of GTM toxicity. This study was designed to evaluate the prospective defensive effect of lysosomal membrane stabilization by imipramine (IMP) against GTM nephrotoxicity in rats. GTM (30 mg/kg/h) was intraperitoneally administered over 4 h daily (120 mg/kg/day) for 7 days. IMP (30 mg/kg/day) was orally administered for 14 days; starting 7 days before and then concurrently with GTM. On 15th day, samples (urine, blood, kidney) were collected to estimate biomarkers of kidney function, lysosomal stability, apoptosis, and inflammation. IMP administration to GTM-treated rats ameliorated the disruption in lysosomal membrane stability induced by GTM. That was evidenced by enhanced renal protein expressions of LAMP2 and PI3K, but reduced cathepsin D cytoplasmic expression in kidney sections. Besides, IMP guarded against apoptosis in GTM-treated rats by down-regulation of the pro-apoptotic (tBid, Bax, cytochrome c) and the effector cleaved caspase-3 expressions, while the anti-apoptotic Bcl-2 expression was enhanced. Additionally, the inflammatory cascade p38 MAPK/NF-κB/TNF-α was attenuated in GTM + IMP group along with marked improvement in kidney function biomarkers, compared to GTM group. These findings were supported by the obvious improvement in histological architecture. Furthermore, in vitro enhancement of the antibacterial activity of GTM by IMP confers an additional benefit to their combination. Conclusively, lysosomal membrane stabilization by IMP with subsequent suppression of tBid/cytochrome c/cleaved caspase-3 apoptotic signaling could be a promising protective strategy against GTM nephrotoxicity.

Regulation of renal nitric oxide and eNOS/iNOS expression by tadalafil participates in the mitigation of amphotericin B-induced renal injury: Down-regulation of NF-κB/iNOS/caspase-3 signaling.

Amphotericin B (AmB)-induced acute kidney injury (AKI) is a common health problem having an undesirable impact on its urgent therapeutic utility for fatal systemic fungal infections. Tadalafil (TAD), a phosphodiesterase-5 (PDE-5) inhibitor, has been observed to have a wide range of pharmacological actions, including nephroprotection. The study's objective was to examine the possible underlying protective mechanism of TAD against AmB-induced nephrotoxicity. Experimentally, animals were divided randomly into four groups: control, TAD (5 mg/kg/day; p.o.), AmB (18.5 mg/kg/day; i.p.), and TAD+AmB groups. Sera and tissue samples were processed for biochemical, molecular, and histological analyses. The biochemical investigations showed that TAD significantly ameliorated the increase of kidney function biomarkers (creatinine, urea, CysC, KIM-1) in serum, renal nitric oxide (NO), lipid peroxidation (MDA), and inflammatory cytokines (TNF-α, IL-6) in AmB-treated rats. Meanwhile, TAD significantly retarded AmB-induced decrease in serum magnesium, sodium, potassium, and renal glutathione content. Molecular analysis revealed that TAD reduced AmB-induced imbalance in the protein expression of eNOS/iNOS, which explains its regulatory effect on renal NO content. These results were also supported by the down-regulation of nuclear NF-κB p65 and cleaved caspase-3 protein expressions, as well as the improvement of histological features by TAD in AmB-treated rats. Therefore, it can be suggested that TAD could be a promising candidate for renoprotection against AmB-induced AKI. That could be partly attributed to its regulatory effect on renal eNOS/iNOS balance and NO, the inhibition of NF-κB p65 nuclear translocation, its downstream inflammatory cytokines and iNOS, and ultimately the inhibition of caspase-3-induced renal apoptosis.