Pentoxifylline and Norcantharidin Modify p62 Expression in 2D and 3D Cultures of B16F1 Cells.

Three-dimensional cell cultures have improved the evaluation of drugs for cancer therapy, due to their high similarity to solid tumors. In melanoma, autophagy appears to show a dual role depending on the progression of the disease. p62 protein has been proposed for the evaluation of autophagic flux since its expression is an indicator of the state of autophagy. Pentoxifylline (PTX) and Norcantharidin (NCTD) are drugs that have been shown to possess anticancer effects. In this work, we used B16F1 mouse melanoma cells in two-dimensional (2D) monolayer cultures and three-dimensional (3D) spheroids to test the effect of PTX and NCTD over the p62 expression. We analyzed the effect on p62 expression through Western blot and immunofluorescence assays. Our results indicate that PTX decreases p62 expression in both cell culture models, while Norcantharidin increases its expression in 3D cultures at 24 h. Therefore, these drugs could have a potential therapeutic use for the regulation of autophagy in melanoma, depending on the state of evolution of the disease.

Pentoxifylline Inhibits TNF-α/TGF-ß1-Induced Epithelial-Mesenchymal Transition via Suppressing the NF-κB Pathway and SERPINE1 Expression in CaSki Cells.

Cervical cancer (CC) is one of the most common and deadly types of female cancer worldwide. Late diagnosis in CC increases the risk of tumor cells spreading to distant organs (metastasis). The epithelial-mesenchymal transition (EMT) is a fundamental process of cancer metastasis. Inflammation can lead to tumor progression, EMT induction, and metastasis. The inflammatory microenvironment is a potent inducer of EMT; inflammatory cytokines such as Tumor Necrosis Factor-alpha (TNF-α) and Transforming growth factor-beta (TGF-ß1) activate transcriptional factors such as STAT3, Snail, Smad, and the Nuclear Factor kappa light-chain-enhancer of activated beta cells (NF-κΒ), which drive EMT. Anti-inflammatory compounds may be an option in the disruption of EMT. PenToXifylline (PTX) possesses potent anti-inflammatory effects by inhibiting NF-κB activity. In addition, PTX exerts an anti-fibrotic effect by decreasing Smad2/3/4. We hypothesize that PTX could exert anti-EMT effects. CaSki human cervical tumor cells were exposed to TNF-α 10 ng/mL and TGF-ß1 alone or in combination for 5 days. Our results revealed that TNF-α and TGF-ß1 induced N-cadherin and Vimentin, confirming the induction of EMT. Furthermore, the combination of cytokines synergized the expression of mesenchymal proteins, enhanced IκBα and p65 phosphorylation, and upregulated Serpin family E member 1 (SERPINE1) mRNA. PTX pretreatment prior to the addition of TNF-α and TGF-ß1 significantly reduced N-cadherin and Vimentin levels. To our knowledge, this is the first time that this effect of PTX has been reported. Additionally, PTX reduced the phosphorylation of IκB-α and p65 and significantly decreased SERPINE1 expression, cell proliferation, migration, and invasion. In conclusion, PTX may counteract EMT in cervical cancer cells by decreasing the NF-κB and SERPINE1.

Pentoxifylline reduces inflammation and prevents myocardial perfusion derangements in experimental chronic Chagas' cardiomyopathy.

BACKGROUND: Myocardial perfusion defect (MPD) is common in chronic Chagas cardiomyopathy (CCC) and is associated with inflammation and development of left ventricular systolic dysfunction. We tested the hypothesis that pentoxifylline (PTX) could reduce inflammation and prevent the development of MPD in a model of CCC in hamsters. METHODS AND RESULTS: We investigated with echocardiogram and rest myocardial perfusion scintigraphy at baseline (6-months after T. cruzi infection/saline) and post-treatment (after additional 2-months of PTX/saline administration), female Syrian hamsters assigned to 3 groups: T. cruzi-infected animals treated with PTX (CH + PTX) or saline (CH + SLN); and uninfected control animals (CO). At the baseline, all groups showed similar left ventricular ejection fraction (LVEF) and MPD areas. At post-treatment evaluation, there was a significant increase of MPD in CH + SLN group (0.8 ± 1.6 to 9.4 ± 9.7%), but not in CH + PTX (1.9 ± 3.0% to 2.7 ± 2.7%) that exhibited MPD area similar to CO (0.0 ± 0.0% to 0.0 ± 0.0%). The LVEF decreased in both infected groups. Histological analysis showed a reduced inflammatory infiltrate in CH + PTX group (395.7 ± 88.3 cell/mm2), as compared to CH + SLN (515.1 ± 133.0 cell/mm2), but larger than CO (193.0 ± 25.7 cell/mm2). The fibrosis and TNF-α expression was higher in both infected groups. CONCLUSIONS: The prolonged use of PTX is associated with positive effects, including prevention of MPD development and reduction of inflammation in the chronic hamster model of CCC.

Treatment with benznidazole and pentoxifylline regulates microRNA transcriptomic profile in a murine model of Chagas chronic cardiomyopathy.

Chronic Chagas cardiomyopathy (CCC) is one of the leading causes of morbidity and mortality due to cardiovascular disorders in endemic areas of Chagas disease (CD), a neglected tropical illness caused by the protozoan parasite Trypanosoma cruzi. CCC is characterized by parasite persistence and inflammatory response in the heart tissue, which occur parallel to microRNA (miRNA) alterations. Here, we investigated the miRNA transcriptome profiling in the cardiac tissue of chronically T. cruzi-infected mice treated with a suboptimal dose of benznidazole (Bz), the immunomodulator pentoxifylline alone (PTX), or the combination of both (Bz+PTX), following the CCC onset. At 150 days post-infection, Bz, PTX, and Bz+PTX treatment regimens improved electrocardiographic alterations, reducing the percentage of mice afflicted by sinus arrhythmia and second-degree atrioventricular block (AVB2) when compared with the vehicle-treated animals. miRNA Transcriptome profiling revealed considerable changes in the differential expression of miRNAs in the Bz and Bz+PTX treatment groups compared with the control (infected, vehicle-treated) group. The latter showed pathways related to organismal abnormalities, cellular development, skeletal muscle development, cardiac enlargement, and fibrosis, likely associated with CCC. Bz-Treated mice exhibited 68 differentially expressed miRNAs related to signaling pathways like cell cycle, cell death and survival, tissue morphology, and connective tissue function. Finally, the Bz+PTX-treated group revealed 58 differentially expressed miRNAs associated with key signaling pathways related to cellular growth and proliferation, tissue development, cardiac fibrosis, damage, and necrosis/cell death. The T. cruzi-induced upregulation of miR-146b-5p, previously shown in acutely infected mice and in vitro T. cruzi-infected cardiomyocytes, was reversed upon Bz and Bz+PTX treatment regimens when further experimentally validated. Our results further our understanding of molecular pathways related to CCC progression and evaluation of treatment response. Moreover, the differentially expressed miRNAs may serve as drug targets, associated molecular therapy, or biomarkers of treatment outcomes.

Histomorphometric and oxidative evaluation of the offspring's testis from type 2 diabetic female rats treated with metformin and pentoxifylline.

Type 2 diabetes mellitus (T2D) during pregnancy is characterized by high levels of reactive oxygen species and pro-inflammatory factors in the placenta. Once these reactive species reach the foetus, they trigger physiological adaptations that allow the foetus to survive, but programme the organism to develop metabolic disorders in adulthood. The male reproductive system is highly susceptible to foetal programming. This study aimed to investigate the effects of intrauterine exposure to T2D on testicular histomorphometry and redox homeostasis of adult rats and evaluate the effects of maternal treatment with metformin and pentoxifylline. Female rats were induced to T2D, then treated with metformin and pentoxifylline, or co-treated with both drugs. The females were mated, the male offspring were sacrificed on postnatal day 90, and the testicles were collected for analysis. Metformin protected the tubular compartment, with the maintenance of the Sertoli cell population and daily sperm production. Pentoxifylline attenuated the effects of diabetes on Leydig cells, in addition to stimulating testosterone production and lowering lipid peroxidation. Intrauterine exposure to T2D results in important testicular alterations that compromise gonadal function, and the co-treatment with metformin and pentoxifylline may represent a promising therapy that attenuates these effects by combining the positive influences in both the tubular and interstitial compartments of the testicular parenchyma.

Modulation of miR-145-5p and miR-146b-5p levels is linked to reduced parasite load in H9C2 Trypanosoma cruzi infected cardiomyoblasts.

In the heart tissue of acutely Trypanosoma cruzi-infected mice miR-145-5p and miR-146b-5p are, respectively, downregulated and upregulated. Here, we used the H9C2 rat cardiomyoblast cell line infected with the Colombian T. cruzi strain to investigate the parasite-host cell interplay, focusing on the regulation of miR-145-5p and miR-146b-5p expression. Next, we explored the effects of interventions with the trypanosomicidal drug Benznidazole (Bz) alone or combined with Pentoxifylline (PTX), a methylxanthine derivative shown to modulate immunological and cardiac abnormalities in a model of chronic chagasic cardiomyopathy, on parasite load and expression of miR-145-5p and miR-146b-5p. The infection of H9C2 cells with trypomastigote forms allowed parasite cycle with intracellular forms multiplication and trypomastigote release. After 48 and 144 h of infection, upregulation of miR-145-5p (24 h: 2.38 ± 0.26; 48 h: 3.15 ± 0.9-fold change) and miR-146b-5b (24 h: 2.60 ± 0.46; 48 h: 2.97 ± 0.23-fold change) was detected. The peak of both miRNA levels paralleled with release of trypomastigote forms. Addition of 3 µM and 10 µM of Bz 48 h after infection reduced parasite load but did not interfere with miR-145-5p and miR-146b-5p levels. Addition of PTX did not interfere with Bz-induced parasite control efficacy. Conversely, combined Bz + PTX treatment decreased the levels of both microRNAs, resembling the expression levels detected in non-infected H9C2 cells. Moreover, the use of miR-145-5p and miR-146b-5p mimic/inhibitor systems before infection of H9C2 cells decreased parasite load, 72 h postinfection. When H9C2 cells were treated with miR-145-5p and miR-146b-5p mimic/inhibitor 48 h after infection, all the used systems, except the miR-146b-5p inhibitor, reduced parasite load. Altogether, our data indicate that these microRNAs putatively control signaling pathways crucial for parasite-host cell interaction. Thus, miR-145-5p and miR-146b-5p deserve to be further investigated as biomarkers of parasite control and tools to identify therapeutic adjuvants to etiological treatment in Chagas disease.

Pentoxifylline, tocopherol, and sequestrectomy are effective for the management of advanced osteoradionecrosis of the jaws-a case series.

BACKGROUND: The aim of the present study was to evaluate the efficacy of pentoxifylline and tocopherol for the management of osteoradionecrosis of the jaws. METHODS: Twenty-five patients diagnosed with osteoradionecrosis of the jaws treated with pentoxifylline 400 mg + tocopherol 400 mg three times daily (tid) were evaluated. Clinical records and image tests were reviewed. All patients were previously submitted to head and neck radiation therapy and presented with a clinical and radiographic diagnosis of osteoradionecrosis of the jaws. RESULTS: Following therapy with pentoxifylline and tocopherol, 76% (19/25) of the patients showed complete mucosal healing, in which 47.3% (9/19) did not undergo sequestrectomy. From this particular group, 77.7% (7/9) were in stage I and 33.3% (3/9) used the protocol for up to 3 months. Among those who underwent to sequestrectomy, complete mucosal healing was observed in 52.7% (10/19). Among these, 60% (6/10) were in stage I and 100% of the patients were using the protocol for more than 3 months. In all other patients, partial healing of the mucosa was observed since they presented advanced disease. These represented 24% of the sample (6/25), 66.6% (4/6) were in stage III, and 60% (4/6) used the protocol for over 6 months. CONCLUSION: Pentoxifylline and tocopherol may provide effective management of osteoradionecrosis of the jaws, and the association with sequestrectomy may avoid major surgical procedures.

Benefits of pentoxifylline for skin flap tissue repair in rats.

PURPOSE: To assess the action of pentoxifylline, administered by subcutaneous route, on skin flap tissue repair in rats, and to verify the histological aspects and biomarkers. METHODS: Thirty-two male Wistar rats were divided into four groups: control (CT) and treated with pentoxifylline (P1, P3 and P5). Modified McFarlane technique flap was used. Ten days later, the animals were euthanized and the areas of viable and necrotic tissue were evaluated. Hematoxylin/eosin staining was used to assess the morphometric characteristics of the number of vessels and epithelial thickness. Picrosirius red was used to assess collagen density. VEGF and TGF-?1 levels on the skin flap and serum of the animals were measured by the ELISA method. RESULTS: The macroscopic evaluation of the skin flap dimensions showed reduced necrotic tissue in the pentoxifylline (p < 0.05) treated groups. There was an increase in angiogenesis and reepithelization, demonstrated by analyses with an increased number of vessels (p < 0.05), VEGF and epithelial thickness. Fibrogenic effect showed decreased collagen density and TGF-ß1 in the skin flap and serum. CONCLUSION: The benefits of pentoxifylline administered by subcutaneous route, at dose 100 mg/kg, which was effective to improve the survival of skin flap by acting on tissue repair components, stimulating angiogenesis and reepithelization, in addition to reducing fibrogenesis.

Pentoxifylline mitigates renal glycoxidative stress in obese mice by inhibiting AGE/RAGE signaling and increasing glyoxalase levels.

AIM: The pharmacological properties of pentoxifylline have been re-evaluated, particularly in chronic kidney disease in diabetes, favored by its anti-inflammatory action. Definitive evidences of renal outcomes are lacking, which indicates the need for investigation of novel mechanisms of action of pentoxifylline. We postulated that components associated with the metabolism of advanced glycation end products (AGEs) may be modulated by pentoxifylline, which consequently decreases the detrimental effects of obesity on kidneys. MAIN METHODS: C57BL-6J mice were fed a high-fat diet for 14 weeks and treated with 50 mg/kg pentoxifylline during the last 7 weeks. Changes in the renal levels of AGE metabolism-associated components were investigated, with particular focus on the receptor for AGEs (RAGE), its downstream components, and components related to AGE detoxification, including glyoxalase 1 (GLO 1). KEY FINDINGS: Pentoxifylline reduced body weight gain, improved insulin sensitivity and glucose tolerance, downregulated biomarkers of glycoxidative stress, and enhanced plasma paraoxonase 1 activity. In the kidneys, pentoxifylline inhibited glomerular expansion, lipid deposition, reduced pro-inflammatory cytokine levels, and induced the activation of AMP-activated protein kinase. Pentoxifylline inhibited the renal accumulation of AGEs and reduced the levels of RAGE and its downstream components, and consequently mitigated oxidative stress and apoptosis. Pentoxifylline also increased the renal levels of GLO 1 and the activities of antioxidant enzymes. Urinary albumin levels were observed to be lowered, which reconfirmed the antialbuminuric effects of pentoxifylline. SIGNIFICANCE: The novel mechanisms of action help explain the renoprotective effects of pentoxifylline and the attenuation of obesity-associated renal complications related to glycoxidative stress.

Potential usefulness of pentoxifylline, a non-specific phosphodiesterase inhibitor with anti-inflammatory, anti-thrombotic, antioxidant, and anti-fibrogenic properties, in the treatment of SARS-CoV-2.

Although most patients with coronavirus disease 2019 (COVID-19) have a good prognosis, in some cases, the disease progresses rapidly, and the mortality rate is high. Some evidence suggests that infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) produces a 'cytokine storm', which is related to acute respiratory distress syndrome or multi-organ dysfunction leading to physiological deterioration and death. It is important to highlight the state of hypercoagulability that can be triggered, involving microvascular thrombosis and vascular occlusive events, which are relevant to such poor outcomes. At present, no specific antiviral drug or vaccine is available for SARS-CoV-2 infection, and current research is aimed at preventing and mitigating damage to the target organs, mainly the lungs. In seeking therapies for patients with COVID-19, immunomodulators, cytokine antagonists and early anti-coagulation therapies have been tested in attempts to reduce the mortality rate. Pentoxifylline, a non-specific phosphodiesterase inhibitor widely used to improve the rheological properties of blood, has beneficial anti-inflammatory properties and can significantly reduce the serum levels of pro-inflammatory cytokines such as interleukin (IL)-6, IL-1, tumour necrosis factor-alpha, C-reactive protein and other immunoregulators. It has also been found to exert anti-thrombotic, antioxidant and anti-fibrogenic actions. These properties could help to prevent or mitigate the inflammatory response and hypercoagulability that develop with SARS-CoV-2 infection, decreasing multi-organ dysfunction manifesting primarily as acute lung injury.

TNF-α inhibition decreases MMP-2 activity, reactive oxygen species formation and improves hypertensive vascular hypertrophy independent of its effects on blood pressure.

Systemic arterial hypertension is a public health problem associated with an increased risk of cardiovascular disease. Matrix metalloproteinases (MMP) are endopeptidases that participate in hypertension-induced cardiovascular remodeling, which may be activated by oxidative stress. Angiotensin II (Ang II), a potent hypertrophic and vasoconstrictor peptide, increases oxidative stress, MMP-2 activity and tumor necrosis factor (TNF-α) expression. In vitro studies have shown that TNF-α is essential for Ang II-induced MMP-2 expression. Thus, this study evaluated whetherTNF-α inhibition decreases the development of hypertension-induced vascular remodeling via reduction of MMP-2 activity and reactive oxygen species (ROS) formation. Two distinct pharmacological approaches were used in the present study: Pentoxifylline (PTX), a non-selective inhibitor of phosphodiesterases that exerts anti- inflammatory effects via inhibition of TNF-α, and Etanercept (ETN), a selective TNF-α inhibitor. 2-kidney and 1-Clip (2K1C). 2-kidney and 1-Clip (2K1C) and Sham rats were treated with Vehicle, PTX (50 mg/Kg and 100 mg/kg daily) or ETN (0.3 mg/Kg and 1 mg/kg; three times per week). Systolic blood pressure (SBP) was measured weekly by tail cuff plethysmography. Plasma TNF-α and IL-1ß levels were evaluated by enzyme-linked immunosorbent assay (ELISA) technique. The vascular hypertrophy was examined in the aorta sections stained with hematoxylin/eosin. ROS in aortas was evaluated by dihydroethidium and chemiluminescence lucigenin assay. Aortic MMP-2 levels and activity were evaluated by gel zymography and in situ zymography, respectively. The 2K1C animals showed a progressive increase in SBP levels and was accompanied by significant vascular hypertrophy (p < 0.05 vs Sham). Treatment with PTX at higher doses decreased SBP and vascular remodeling in 2K1C animals (p < 0.05 vs 2K1C vehicle). Although the highest dose of ETN treatment did not reduce blood pressure, the vascular hypertrophy was significantly attenuated in 2K1C animals treated with ETN1 (p < 0.05). The increased cytokine levels and ROS formation were reversed by the highest doses of both PTX and ETN. The increase in MMP-2 levels and activity in 2K1C animals were reduced by PTX100 and ETN1 treatments (p < 0.05 vs vehicle 2K1C). Lower doses of PTX and ETN did not affect any of the evaluated parameters in this study, except for a small reduction in TNF-α levels. The findings of the present study suggest that PTX and ETN treatment exerts immunomodulatory effects, blunted excessive ROS formation, and decreased renovascular hypertension-induced MMP-2 up-regulation, leading to improvement ofvascular remodeling typically found in 2K1C hypertension. Therefore, strategies using anti-hypertensive drugs in combination with TNF alpha inhibitors could be an attractive therapeutic approach to tackle hypertension and its associated vascular remodeling.

Benefits of pentoxifylline for skin flap tissue repair in rats

Abstract Purpose To assess the action of pentoxifylline, administered by subcutaneous route, on skin flap tissue repair in rats, and to verify the histological aspects and biomarkers. Methods Thirty-two male Wistar rats were divided into four groups: control (CT) and treated with pentoxifylline (P1, P3 and P5). Modified McFarlane technique flap was used. Ten days later, the animals were euthanized and the areas of viable and necrotic tissue were evaluated. Hematoxylin/eosin staining was used to assess the morphometric characteristics of the number of vessels and epithelial thickness. Picrosirius red was used to assess collagen density. VEGF and TGF-?1 levels on the skin flap and serum of the animals were measured by the ELISA method. Results The macroscopic evaluation of the skin flap dimensions showed reduced necrotic tissue in the pentoxifylline (p < 0.05) treated groups. There was an increase in angiogenesis and reepithelization, demonstrated by analyses with an increased number of vessels (p < 0.05), VEGF and epithelial thickness. Fibrogenic effect showed decreased collagen density and TGF-β1 in the skin flap and serum. Conclusion The benefits of pentoxifylline administered by subcutaneous route, at dose 100 mg/kg, which was effective to improve the survival of skin flap by acting on tissue repair components, stimulating angiogenesis and reepithelization, in addition to reducing fibrogenesis

Effects of pentoxifylline supplementation to semen extender on post-breeding inflammation response assessed by endometrial cytology and vascular perfusion in mares.

The aim was to evaluate effects of addition of pentoxifylline to skimmed milk semen extender on uterine inflammatory response. Thirty-six estrous cycles of 15 mares were randomly divided into five groups for artificial insemination (AI): Control: mimicking the AI procedure (n = 7); Extender: deposition of skimmed milk based extender (n = 7); Extender + PTX: skimmed milk based extender plus pentoxifylline (7.18 mM; n = 8); Semen: semen diluted with extender without pentoxifylline (n = 7), and Semen + PTX: semen diluted with extender containing pentoxifylline (n = 7). Mares in estrus were examined by trans-rectal palpation and using ultrasonography, and ovulation was induced. Uterine hemodynamics were assessed immediately before ovulation induction (T-30), immediately before AI (T0), 2 (T2), 6 (T6), 12 (T12), 24 (T24) and 48 (T48) h after AI. Endometrial samples were collected 6 h after AI, and slides were stained and examined to determine percentage of PMN. Pentoxifylline had no additional effect on vascular perfusion. There was a major inflammatory response with pentoxifylline treatment that was greater than that of the control group. In the group treated with Extender + PTX, there were more PMN (57.98 ±â€¯9.42%) than in the group treated with Extender (20.20 ±â€¯6.63%) and in the Semen + PTX group more PMN (82.84 ±â€¯5.71%) than in the Semen-treated group (47.83 ±â€¯10.61%). These findings indicate the addition of pentoxifylline does not stimulate blood flow; however, it induces a greater immune defense response because more neutrophils migrate to the uterine lumen.

Hypertonic saline and pentoxifylline enhance survival, reducing apoptosis and oxidative stress in a rat model of strangulated closed loop small bowel obstruction.

OBJECTIVES: Intestinal obstruction has a high mortality rate when therapeutic treatment is delayed. Resuscitation in intestinal obstruction requires a large volume of fluid, and fluid combinations have been studied. Therefore, we evaluated the effects of hypertonic saline solution (HS) with pentoxifylline (PTX) on apoptosis, oxidative stress and survival rate. METHODS: Wistar rats were subjected to intestinal obstruction and ischemia through a closed loop ligation of the terminal ileum and its vessels. After 24 hours, the necrotic bowel segment was resected, and the animals were randomized into four groups according to the following resuscitation strategies: Ringer's lactate solution (RL) (RL-32 ml/kg); RL+PTX (25 mg/kg); HS+PTX (HS, 7.5%, 4 ml/kg), and no resuscitation (IO-intestinal obstruction and ischemia). Euthanasia was performed 3 hours after resuscitation to obtain kidney and intestine samples. A malondialdehyde (MDA) assay was performed to evaluate oxidative stress, and histochemical analyses (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling [TUNEL], Bcl-2 and Bax) were conducted to evaluate kidney apoptosis. Survival was analyzed with another series of animals that were observed for 15 days. RESULTS: PTX in combination with RL or HS reduced the MDA levels (nmol/mg of protein), as follows: kidney IO=0.42; RL=0.49; RL+PTX=0.31; HS+PTX=0.34 (p<0.05); intestine: IO=0.42; RL=0.48; RL+PTX=0.29; HS+PTX=0.26 (p<0.05). The number of labeled cells for TUNEL and Bax was lower in the HS+PTX group than in the other groups (p<0.05). The Bax/Bcl-2 ratio was lower in the HS+PTX group than in the other groups (p<0.05). The survival rate on the 15th day was higher in the HS+PTX group (77%) than in the RL+PTX group (11%). CONCLUSION: PTX in combination with HS enhanced survival and attenuated oxidative stress and apoptosis. However, when combined with RL, PTX did not reduce apoptosis or mortality.

Combination of pentoxifylline and α-galactosylceramide with radiotherapy promotes necro-apoptosis and leukocyte infiltration and reduces the mitosis rate in murine melanoma.

Despite the success for the treatment of melanoma such as targeted molecular therapy, the use of such treatments are expensive For this reason, this study was carried out to explore the anti-cancer properties of available drugs that are able to modify the melanoma prognosis. The study was conducted in two phases: Evaluation of pharmacological effects of pentoxifylline (PTX) administered above (60 mg/kg) which is the therapeutic dose that is aimed at reducing the side-effect of radiotherapy, and of α- galactosylceramide (GalCer) administered at 100 µg/kg, as well as their combination using a murine model (BDF1 mice) of melanoma cell line (B16-F1, ATCC). For the radiotherapy phase, 9 Gy was applied in the tumor area, before (3 days), during (30 min) and after (3 days) the PTX + GalCer treatment. In both study phases, the mitosis rate, leukocyte infiltration and necro-apoptosis were assessed using histological and immunohistochemical approach and tumor volume evaluation as biomarkers. All treatments showed good prognosis results estimated as reduction of mitosis rate (PTX + GalCer after radiotherapy and GalCer), increased leukocyte infiltrate (PTX + GalCer after radiotherapy and GalCer) and necro-apoptosis augmentation (PTX + GalCer after radiotherapy and radiotherapy control). Nevertheless, a lower development of tumor volume was found in GalCer treatment. In this way, it is possible to suggest that the integrated treatment with immuno-stimulators such as GalCer, plus drug used for peripheral vascular disease (PTX) after radiotherapy is probably an alternative for controlling aggressive melanoma in murine model.

Pentoxifylline Enhances the Apoptotic Effect of Carboplatin in Y79 Retinoblastoma Cells.

BACKGROUND/AIM: Retinoblastoma (RB) is the most common primary intraocular malignancy. Carboplatin (CPt) is a DNA damage-inducing agent that is widely used for the treatment of RB. Unfortunately, this drug also activates the transcription factor nuclear factor-kappa B (NF-ĸB), leading to promotion of tumor survival. Pentoxifylline (PTX) is a drug that inhibits the phosphorylation of I kappa B-alpha (IĸBα) in serines 32 and 36, and this disrupts NF-ĸB activity that promotes tumor survival. The goal of this study was to evaluate the effect of the PTX on the antitumor activity of CPt. MATERIALS AND METHODS: Y79 RB cells were treated with CPt, PTX, or both. Cell viability, apoptosis, loss of mitochondrial membrane potential, the activity of caspase-9, -8, and -3, cytochrome c release, cell-cycle progression, p53, and phosphorylation of IĸBα, and pro- and anti-apoptotic genes were evaluated. RESULTS: Both drugs significantly affected the viability of the Y79 RB cells in a time- and dose-dependent manner. The PTX+CPt combination exhibited the highest rate of apoptosis, a decrease in cell viability and significant caspase activation, as well as loss of mitochondrial membrane potential, release of cytochrome c, and increased p53 protein levels. Cells treated with PTX alone displayed decreased I kappa B-alpha phosphorylation, compared to the CPt treated group. In addition, the PTX+CPt combination treatment induced up-regulation of the proapoptotic genes Bax, Bad, Bak, and caspases- 3, -8, and -9, compared to the CPt and PTX individual treated groups. CONCLUSION: PTX induces apoptosis per se and increases the CPt-induced apoptosis, augmenting its antitumor effectiveness.

Hypertonic saline and pentoxifylline enhance survival, reducing apoptosis and oxidative stress in a rat model of strangulated closed loop small bowel obstruction

OBJECTIVES: Intestinal obstruction has a high mortality rate when therapeutic treatment is delayed. Resuscitation in intestinal obstruction requires a large volume of fluid, and fluid combinations have been studied. Therefore, we evaluated the effects of hypertonic saline solution (HS) with pentoxifylline (PTX) on apoptosis, oxidative stress and survival rate. METHODS: Wistar rats were subjected to intestinal obstruction and ischemia through a closed loop ligation of the terminal ileum and its vessels. After 24 hours, the necrotic bowel segment was resected, and the animals were randomized into four groups according to the following resuscitation strategies: Ringer's lactate solution (RL) (RL-32 ml/kg); RL+PTX (25 mg/kg); HS+PTX (HS, 7.5%, 4 ml/kg), and no resuscitation (IO-intestinal obstruction and ischemia). Euthanasia was performed 3 hours after resuscitation to obtain kidney and intestine samples. A malondialdehyde (MDA) assay was performed to evaluate oxidative stress, and histochemical analyses (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling [TUNEL], Bcl-2 and Bax) were conducted to evaluate kidney apoptosis. Survival was analyzed with another series of animals that were observed for 15 days. RESULTS: PTX in combination with RL or HS reduced the MDA levels (nmol/mg of protein), as follows: kidney IO=0.42; RL=0.49; RL+PTX=0.31; HS+PTX=0.34 (p<0.05); intestine: IO=0.42; RL=0.48; RL+PTX=0.29; HS+PTX=0.26 (p<0.05). The number of labeled cells for TUNEL and Bax was lower in the HS+PTX group than in the other groups (p<0.05). The Bax/Bcl-2 ratio was lower in the HS+PTX group than in the other groups (p<0.05). The survival rate on the 15th day was higher in the HS+PTX group (77%) than in the RL+PTX group (11%). CONCLUSION: PTX in combination with HS enhanced survival and attenuated oxidative stress and apoptosis. However, when combined with RL, PTX did not reduce apoptosis or mortality.

Involvement of cAMP/EPAC/Akt signaling in the antiproteolytic effects of pentoxifylline on skeletal muscles of diabetic rats.

Advances in the knowledge of the mechanisms controlling protein breakdown in skeletal muscles have allowed the exploration of new options for treating muscle-wasting conditions. Pentoxifylline (PTX), a nonselective phosphodiesterase (PDE) inhibitor, attenuates the loss of muscle mass during catabolic conditions, mainly via inhibiting protein breakdown. The aim of this study was to explore the mechanisms by which PTX inhibits proteolysis in the soleus and extensor digitorum longus (EDL) muscles of streptozotocin-induced diabetic rats. The levels of atrogin-1 and muscle RING finger-1 were decreased, as were the activities of caspase-3 (EDL) and calpains (soleus and EDL), in diabetic rats treated with PTX, which at least partly explains the drop in the ubiquitin conjugate (EDL) levels and in proteasome activity (soleus and EDL). Treatment with PTX decreased PDE activity and increased cAMP content in muscles of diabetic rats; moreover, it also increased both the protein levels of exchange protein directly activated by cAMP (EPAC, a cAMP effector) and the phosphorylation of Akt. The loss of muscle mass was practically prevented in diabetic rats treated with PTX. These findings advance our understanding of the mechanisms underlying the antiproteolytic effects of PTX and suggest the use of PDE inhibitors as a strategy to activate cAMP signaling, which is emerging as a promising target for treating muscle mass loss during atrophic conditions. NEW & NOTEWORTHY cAMP signaling has been explored as a strategy to attenuate skeletal muscle atrophies. Therefore, in addition to ß2AR agonists, phosphodiesterase inhibitors such as pentoxifylline (PTX) can be an interesting option. This study advances the understanding of the mechanisms related to the antiproteolytic effects of PTX on skeletal muscles of diabetic rats, which involve the activation of both exchange protein directly activated by cAMP and Akt effectors, inhibiting the expression of atrogenes and calpain/caspase-3-proteolytic machinery.

Surgery-induced changes in erythrocyte and plasma lipid peroxidation, enzymatic and non-enzymatic antioxidants of female rats: protective role of heparin and pentoxifylline

Background: Intra abdominal adhesions are a complication that occurs after many abdominal surgical procedures, especially gynecological operations. These complications occur by irritating the peritoneum due to such circumstances as infection or surgical trauma, and are considered a pathological part of the healing process of peritoneal injury. It manifests itself with symptoms such as pain, intestinal or urethral obstruction and abdominal abscesses. Oxidative stress due to adhesions plays an important role on adhesion formation. In addition to many researches done at the point of prevention of adhesion and decreasing stress parameters, in this study, it was planned to determine the effect of Heparin (H) and Pentoxifylline (PTX) on malondialdehyde (MDA) and some antioxidant values.Materials, Methods & Results: This study was performed on rats and thirty-seven female Sprague-Dawley rats were randomized into four groups. The first group was sham (Sh) group (n = 7) and laparotomy was performed and 2 mL of 0.9 % NaCl was applied. For all other rats (n = 30) the small intestine was withdrawn and the uterus was uncovered and the anti mesenteric surfaces of the left uterine horn and left abdominal wall were superficially tilted until slight bleeding was seen. Lesion areas have been covered. Two mL 0.9 % NaCl to control (C) group (n = 10), 500 IU heparin to group H, and 25 mg / kg Pentoxifylline to group PTX (n = 10) have been given and then the abdominal incision was closed. The adhesion score of group Sh was found to be more important than C and PTX groups (P < 0.05). The adhesion score of group C was determined to be more significant than group H (P < 0.05). In group Sh, erythrocyte reduced glutathione (GSH) levels were found to be more significant (P < 0.01) than C, H and PTX groups whereas it was found that group C was more significant than group H (P < 0.01).[...](AU)

Pentoxifylline may restore kanamycin-induced renal damage in rats

Background: Kidney damage can be caused by many factors, such as using certain drugs in high doses or over the long term. The use of one such group of drugs, aminoglycosides, which act as Gram-negative antibacterial therapeutic agents, can lead to nephrotoxicity. It has been hypothesized that aminoglycoside-induced nephrotoxicity might be prevented by using pentoxifylline, which has antioxidant and anti-inflammatory effects and improves microcirculation. The objective of this present research was to determine the protective effects of pentoxifylline on kanamycin-induced kidney damage.Materials, Methods & Results: Thirty-two male Wistar rats were divided into four groups as follows: control, pentoxifylline, kanamycin, and kanamycin + pentoxifylline. The control group received intraperitoneal (IP) injections of 0.5 mL normal saline solution once a day (d) (SID) for 20 d; the pentoxifylline group received IP injections of 50 mg/kg pentoxifylline twice a day (BID) for 20 d, the kanamycin group received subcutaneous (SC) injections of 500 mg/kg kanamycin SID for 20 d, and the kanamycin + pentoxifylline group received both SC injections of 500 mg/kg kanamycin SID and IP injections of 50 mg/kg pentoxifylline BID for 20 d. At the end of 20 d, blood samples were taken from the heart by cardiac puncture under general anesthesia. After euthanizing the rats by cervical dislocation under anesthesia, the kidneys were immediately removed, relative kidney weights were calculated, and routine pathologic evaluations were conducted. Hemogram parameters were measured using a blood cell count apparatus and serum biochemical parameters were measured using an autoanalyzer. Kanamycin also caused (P < 0.05) tubular degeneration and tubular dilatation. Although pentoxifylline significantly reduced the level of kanamycin-induced tubular degeneration (P < 0.05), it did not significantly reduce tubular dilatation.[...](AU)