Clinical Efficacy of Pentoxifylline Combined with Thioctic Acid in the Treatment of Painful Diabetic Peripheral Neuropathy

Objective:To observe the efficacy of pentoxifylline+thioctic acid in the treatment of patients with painful diabetic peripheral neuropathy(PDPN).Methods:70 patients with PDPN admitted from October 2019 to October 2022 were selected and randomly grouped,with pentoxifylline+thioctic acid treatment in Group A and thioctic acid treatment in Group B,and the treatment efficacy was compared.Results:The treatment efficacy in Group A was higher than that of Group B,P<0.05;the points of each symptom of PDPN in Group A were lower than that of Group B,P<0.05;the C-reactive protein and electromyography indexes of PDPN patients in Group A were better than that of Group B,P<0.05.Conclusion:PDPN patients treated with pentoxifylline+thioctic acid can optimize nerve function,inhibit inflammation progression,and reduce PDPN symptoms,which is an efficient and feasible treatment option.

Pentoxifylline versus prednisolone for severe alcoholic hepatitis:A randomized controlled trial

AIM： To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS： Sixty-eight patients with severe alcoholic hepatitis （Maddrey score ≥ 32） received pentoxifylline （n = 34, group Ⅰ） or prednisolone （n = 34, group Ⅱ） for 28 d in a randomized double-blind controlled study, and subsequently in an open study （with a tapering dose of prednisolone） for a total of 3 mo, and were followed up over a period of 12 mo.RESULTS： Twelve patients in group Ⅱ died at the end of 3 mo in contrast to five patients in group Ⅰ. The probability of dying at the end of 3 mo was higher in group Ⅱ as compared to group Ⅰ （35.29% vs 14.71%, P = 0.04; log rank test）. Six patients in group I developed hepatorenal syndrome as compared to none in group Ⅰ. Pentoxifylline was associated with a significantly lower model for end-stage liver disease （MELD） score at the end of 28 d of therapy （15.53± 3.63 vs 17.78± 4.56, P=0.04）. Higher baseline Maddrey score was associated with increased mortality.CONCLUSION： Reduced mortality, improved risk-benefit profile and renoprotective effects of pentoxifylline compared with prednisolone suggest that pentoxifylline is superior to prednisolone for treatment of severe alcoholic hepatitis.

Effects of pentoxifylline on nonalcoholic fatty liver disease: A meta-analysis

AIM: To evaluate the effects of pentoxifylline therapy in patients with nonalcoholic fatty liver disease (NAFLD).

Effects and Clinical Significance of Pentoxifylline on the Oxidative Stress of Rats with Diabetic Nephropathy

Diabetic nephropathy（DN） is a common and serious clinical complication of diabetes and presently there are no effective ways to prevent its occurrence and progression. Recent studies show that pentoxifylline（PTX） can improve renal hemodynamics, reduce urinary protein excretion, and alleviate or delay renal failure in DN patients. In this study, we focused on the anti-oxidative stress effect of PTX on alleviating renal damages of DN using rat models. DN rats were established with injection of streptozotocin. Blood glucose, urinary protein excretion, serum cystatin C, renal biopsy, superoxide dismutase（SOD） and malondialdehyde（MDA） in serum and renal homogenate and renal nitrotyrosine levels were analyzed before and 12 weeks after the treatment of PTX. Before treatment, all the DN rats had elevated blood glucose, increased urinary protein excretion and elevated serum cystatin C. Morphologically, DN rats exhibited renal tissue damages, including swelling and fusions of foot processes of podocytes under electron microscope. Masson staining revealed blue collagen deposition in glomeruli and renal interstitium. With treatment of PTX, symptoms and renal pathological changes of DN rats were alleviated. Furthermore, the MDA levels were increased and the SOD levels were decreased in the serum and kidneys of DN rats, and these changes were reversed by PTX. The expression of nitrotyrosine was up-regulated in DN rat model and down-regulated by PTX, indicating that PTX was able to inhibit oxidative reactions in DN rats. PTX could alleviate renal damage in DN, which may be attributable to its anti-oxidative stress activity.

Pentoxifylline:A first line treatment option for severe alcoholic hepatitis and hepatorenal syndrome?

Although favourable results of pentoxifylline （PTX） used in treatment of severe alcoholic hepatitis patients with a Maddrey discriminant function score ≥ 32 have been previously reported, it is not currently recommended as a first line treatment for alcoholic hepatitis owing to lack of evidence for its efficacy as compared to the standard treatment with corticosteroids. In a very recent issue of World Journal of Gastroenterology, Dr. De BK and colleagues compared for the first time the two treatment modalities head to head in a randomized controlled study, demonstrating the advantage of PTX over corticosteroids in terms of patients＇ survival and risk-benefit profile. The advantage of PTX over corticosteroids in survival of patients with severe alcoholic hepatitis was found to be related to the prevention of hepatorenal syndrome in their study. This study raises the question of the use of PI-X as a standard treatment for severe alcoholic hepatitis. Considering the fact that PTX presented a spectacular efficiency in prevention of hepatorenal syndrome in their study as well as that previous studies have shown that this effect is possibly related to a primary renoprotective action because it is irrelevant of tumor necrosis factor-c~ synthesis inhibition or improved liver function, we tempted to speculate that PXT might be an effective option for prevention and/or treatment of hepatorenal syndrome complicating other forms of advanced liver disease. This attractive theory remains to be elucidated by pressing future studies in view of the lack of effective treatment modalities for hepatorenal syndrome.

Corticosteroids and pentoxifylline for the treatment of alcoholic hepatitis:Current status

The treatment of choice for patients with severe alcoholic hepatitis (AH) is use of corticosteroids.Many randomized well designed studies have been reported from all over the world on the use of corticosteroids in the treatment of AH.However,the data on the efficacy of corticosteroids in these patients have been conflicting.Initial meta-analyses also failed to show beneficial effects of corticosteroids.Based on individual data meta-analysis showing clear benefit of corticosteroids amongst patients with severe AH (modified discriminant function of 32 or more),led American College of Gastroenterology to recommend use of corticosteroids as the first line treatment option amongst patients with severe AH.However,corticosteroids are relatively contraindicated amongst patients with severe AH and coexistent sepsis,gastrointestinal bleeding,and acute pancreatitis.These patients may be candidates for second line treatment with pentoxifylline.Further,specific treatment of AH with corticosteroids far from satisfactory with as many as 40%-50% of patients failing to respond to steroids,thus classified as nonresponsive to steroids.The management of these patients is a continuing challenge for physicians.Better treatment modalities need to be developed for this group of patients in order to improve the outcome of patients with severe AH.This article describes at length the available trials on use of corticosteroids and pentoxifylline with their current status.Route of administration,dosage,adverse effects,and mechanisms of action of these two drugs are also discussed.Finally,an algorithm with clinical approach to management of patients who present with clinical syndrome of AH is described.

Pentoxifylline in hepatopulmonary syndrome

AIM： To determine the effects of pentoxifylline （PTX） on clinical manifestations and evaluate arterial blood gas data in hepatopulmonary syndrome （HPS） in chil- dren. METHODS： In a pilot study of 10 children with chronic liver disease, who had HPS, 20 mg/kg/d PTX was ad- ministered for 3 mo. Clinical data and arterial blood gas parameters were evaluated at baseline, the end of the treatment period, and 3 mo after drug discontinuation. RESULTS： Six patients could tolerate PTX, while four patients experienced complications, Among patients who could tolerate PTX, there was a significant increase in arterial oxygen pressure （PaO2） （P = 0,02） and oxy- gen saturation （Sa02） （P = 0.04） and alveolar-arterial oxygen gradient （P = 0.02） after 3 mo of treatment. Significant decreases in Pa02 （P = 0.02） and alveolararterial oxygen gradient （P = 0.02） were also seen after drug discontinuation. CONCLUSION： PTX may improve PaO2, Sa02 and alve- olar-arterial oxygen gradient in the early stage of HPS.

Pentoxifylline treatment and penile calcifications in men Nith Peyronie＇s disease

This retrospective cohort study from a single clinical practice enrolled patients with evidence of calcified Peyronie＇s disease （PD） plaques detected on penile ultrasound at the time of initial presentation. The primary objective was to describe the effect of pentoxifylline （PTX） treatment on subtunical calcifications in men with PD. A PD-specific questionnaire was administered and sonographic evaluations were performed at baseline and follow-up visits. Descriptive statistics and X2 analysis were used to characterize the effect of PTX on calcified tunical plaques. In all, 71 men （mean age： 51.9 years） with PD and sonographic evidence of calcification were identified. Of them, 62 of these men were treated with PTX for a mean duration of I year, and nine with vitamin E or no treatment. Improvement or stabilization in calcium burden at follow-up was noted in 57 （91.9%） of men treated with PTX versus four （44,4%） of those not treated with PTX （P〈0.001）. PTX users were much less likely to have a subjective worsening of their clinical condition （25.0% versus 78.3%, P=0.002）. Treatment with PTX appeared to stabilize or reduce calcium content in PD plaques. A randomized controlled trial is warranted to further explore this effect.

Pentoxifylline enhances the protective effects of hypertonic saline solution on liver ischemia reperfusion injury through inhibition of oxidative stress

BACKGROUND：Liver ischemia reperfusion（IR）injury triggers a systemic inflammatory response and is the main cause of organ dysfunction and adverse postoperative outcomes after liver surgery.Pentoxifylline（PTX）and hypertonic saline solution（HTS）have been identified to have beneficial effects against IR injury.This study aimed to investigate if the addition of PTX to HTS is superior to HTS alone for the prevention of liver IR injury.METHODS： Male Wistar rats were allocated into three groups. Control rats underwent 60 minutes of partial liver ischemia, HTS rats were treated with 0.4 mL/kg of intravenous 7.5% NaCl 15 minutes before reperfusion, and HPTX group were treated with 7.5% NaC1 plus 25 mg/kg of PTX 15 minutes before reperfusion. Samples were collected after reperfusion for determination of ALT, AST, TNF-α, IL-6, IL-10, mitochondrial respiration, lipid peroxidation, pulmonary permeability and myeloperoxidase. RESULTS： HPTX significantly decreased TNF-α 30 minutes after reperfusion. HPTX and HTS significantly decreased ALT,AST, IL-6, mitochondrial dysfunction and pulmonary myelo- peroxidase 4 hours after reperfusion. Compared with HTS only, HPTX significantly decreased hepatic oxidative stress 4 hours after reperfusion and pulmonary permeability 4 and 12 hours after reperfusion. CONCLUSION： This study showed that PTX added the beneficial effects of HTS on liver IR injury through decreases of hepatic oxidative stress and pulmonary permeability.

Pentoxifylline improves liver regeneration through downregulation of TNF-α synthesis and TGF-β1 gene expression

AIM:To investigate the mechanism of pentoxifylline(PTX)improvement in liver regeneration.RESULTS:Rats were randomized into 4 groups:Control rats;Sham-sham-operation rats;Saline-70% hepatectomy plus saline solution;PTX-70%hepatectomy plus PTX.At 2 and 6 h after hepatectomy,aspartate aminotransferase,alanine aminotransferase,tumor necrosis factor(TNF)-α and interleukin-6(IL-6)serum and hepatic tissue levels were determined.Tumor growth factor(TGF)-β1 gene expression in liver tissue was evaluated 24 h after hepatectomy by quantitative reverse transcriptase polymerase chain reaction analysis.Proliferation was analyzed by mitotic index and proliferating cell nuclear antigen(PCNA)staining 48 h after hepatectomy.RESULTS:TNF-α and IL-6 serum levels increased at 2 and 6 h after hepatectomy.At 2 h after hepatectomy serum PTX was reduced but not hepatic levels of TNF-α and IL-6.A decrease in liver TGF-β1 gene expression and an increase in mitotic index and PCNA after hepatectomy were observed in the PTX treatment group in comparison to the saline group.CONCLUSION:PTX improves liver regeneration by a mechanism related to down regulation of TNF-α production and TGF-β1 gene expression.

Role of pentoxifylline in non-alcoholic fatty liver disease in high-fat diet-induced obesity in mice

AIM:To study pentoxifylline effects in liver and adipose tissue inflammation in obese mice induced by high-fat diet(HFD).METHODS: Male swiss mice(6-wk old) were fed a highfat diet(HFD; 60% kcal from fat) or AIN-93(control diet; 15% kcal from fat) for 12 wk and received pentoxifylline intraperitoneally(100 mg/kg per day) for the last 14 d. Glucose homeostasis was evaluated by measurements of basal glucose blood levels and insulin tolerance test two days before the end of the protocol. Final body weight was assessed. Epididymal adipose tissue was collected and weighted for adiposity evaluation. Liver and adipose tissue biopsies were homogenized in solubilization buffer and cytokines were measured in supernatant by enzyme immunoassay or multiplex kit, respectively. Hepatic histopathologic analyses were performed in sections of paraformaldehyde-fixed, paraffin-embedded liver specimens stained with hematoxylin-eosin by an independent pathologist. Steatosis(macrovesicular and microvesicular), ballooning degeneration and inflammation were histopathologically determined. Triglycerides measurements were performed after lipid extraction in liver tissue. RESULTS: Pentoxifylline treatment reduced microsteatosis and tumor necrosis factor(TNF)-α in liver(156.3 ± 17.2 and 62.6 ± 7.6 pg/mL of TNF-α for non-treated and treated obese mice, respectively; P < 0.05). Serum aspartate aminotransferase levels were also reduced(23.2 ± 6.9 and 12.1 ± 1.6 U/L for nontreated and treated obese mice, respectively; P < 0.05) but had no effect on glucose homeostasis. In obese adipose tissue, pentoxifylline reduced TNF-α(106.1 ± 17.6 and 51.1 ± 9.6 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) and interleukin-6(340.8 ± 51.3 and 166.6 ± 22.5 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) levels; however, leptin(8.1 ± 0.7 and 23.1 ± 2.9 ng/mL for non-treated and treated lean mice, respectively; P < 0.05) and plasminogen activator inhibitor-1(600.2 ± 32.3 and 1508.6 ± 210.4 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) levels increased in lean adipose tissue. TNF-α level in the liver of lean mice also increased(29.6 ± 6.6 and 75.4 ± 12.6 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) while triglycerides presented a tendency to reduction.CONCLUSION: Pentoxifylline was beneficial in obese mice improving liver and adipose tissue inflammation. Unexpectedly, pentoxifylline increased pro-inflammatory markers in the liver and adipose tissue of lean mice.

Antioxidant potential of pentoxifylline on spermatozoa of small ruminants

Objective:To investigate antioxidant potential of pentoxifylline on spermatozoa of small ruminants including rams and bucks.Methods:The levels of hydrogen peroxide(H2O2)production in ram and buck spermatozoa incubated with 0(control),4 and 8 mM of pentoxifylline were measured after 45-min incubation.Then,the motility parameters of ram and buck spermatozoa incubated with 0(control),1 mM of H2O2,1 mM of H2O2 plus 4 mM of pentoxifylline,and 1 mM of H2O2 plus 8 mM of pentoxifylline were analysed.H2O2 was estimated using a fluorometric assay and spermatozoa motility characteristics were analyzed using computer aided sperm analyzer.Results:Pentoxifylline significantly decreased the levels of H2O2 produced from both ram and buck spermatozoa(P<0.05),and significant lower rates of H2O2 formation were noted when 8 mM of pentoxifylline was added(P<0.05).The values of all sperm motility parameters for the two species significantly decreased after incubation with H2O2(P<0.05).In contrast,when the spermatozoa were incubated with both H2O2 and two concentrations of pentoxifylline,the motility values rose significantly compared to those incubated with H2O2 alone(P<0.05).For both ram and buck sperm samples,the rapid and static subpopulation motility parameters were the most affected categories by pentoxifylline addition compared to the medium and slow categories.Conclusions:Pentoxifylline possesses an antioxidant capacity proved by its ability of reducing H2O2 levels as well as by increasing motility values of stressed spermatozoa.Therefore,pentoxifylline could be recommended as antioxidant additive for spermatozoa of small ruminants under stress conditions.

Pentoxifylline suppressed LPS-induced inflammatory and apoptotic signaling in neuronal cells

Several studies have reported a relation between increased pro-inflammatory mediators such as TNF-α and apoptosis in neurodegenerative diseases such as Alzheimer’s disease (AD). It is known that lipopoly-saccharide (LPS) treatment induces neuroinflammation and memory deterioration, and it has been reported that LPS induces apoptosis mostly through the production of TNF-α. Pentoxifylline (PTX), is a vascular protective agent and a potent TNF-alpha inhibitor. However, the molecular neuroprotective mechanisms of PTX against LPS-induced neurotoxicity have not been well studied. In this study, we investigated the direct protective effect of PTX against LPS-induced toxicity in Rat pheochromocytoma (PC12) cell line. The results showed that a pretreatment with PTX prior exposure to LPS signifycantly decreased LPS-induced cell death. Mechanisms study showed that PTX has the potential to inhibit pro-inflammatory and pro-apoptotic pathways via the suppression of TNF-α and a caspase-dependent pathway in neuronal PC12 cells. This is the first study to report the anti-inflammatory and anti-apoptotic effects of PTX via inhibition of TNF-α and a caspase-dependent pathway in neuronal PC12 cells. Altogether, these observations indicate that PTX is capable of promoting neuroprotective effects, meanwhile also present some insights into the potential signaling pathways that are involved. Thus, these findings support the potential for PTX to be investigated as a potential agent for the treatment of neurodegenerative diseases such as AD.

Pentoxifylline Inhibits Liver Fibrosis via Hedgehog Signaling Pathway

Infection of schistosomiasis japonica may eventually lead to liver fibrosis, and no effective antifibrotic therapies are available but liver transplantation. Hedgehog（HH） signaling pathway has been involved in the process and is a promising target for treating liver fibrosis. This study aimed to explore the effects of pentoxifylline（PTX） on liver fibrosis induced by schistosoma japonicum infection by inhibiting the HH signaling pathway. Phorbol12-myristate13-acetate（PMA） was used to induce human acute mononuclear leukemia cells THP-1 to differentiate into macrophages. The THP-1-derived macrophages were stimulated by soluble egg antigen（SEA）, and the culture supernatants were collected for detection of activation of macrophages. Cell Counting Kit-8（CCK-8） was used to detect the cytotoxicity of the culture supernatant and PTX on the LX-2 cells. The LX-2 cells were administered with activated culture supernatant from macrophages and（or） PTX to detect the transforming growth factor-β gene expression. The m RNA expression of shh and gli-1, key parts in HH signaling pathway, was detected. The m RNA expression of shh and gli-1 was increased in LX-2 cells treated with activated macrophages-derived culture supernatant, suggesting HH signaling pathway may play a key role in the activation process of hepatic stellate cells（HSCs）. The expression of these genes decreased in LX-2 cells co-cultured with both activated macrophages-derived culture supernatant and PTX, indicating PTX could suppress the activation process of HSCs. In conclusion, these data provide evidence that PTX prevents liver fibrogenesis in vitro by the suppression of HH signaling pathway.

Spectrophotometric Study for the Reaction of Pentoxifylline Hydrochloride with 1,2-Naphthoquinone-4-Sulphonate: Kinetics, Mechanism and Application for Development of High-Throughput Kinetic Microwell Assay for Pentoxifylline in Quality Control Laboratory

Spectrophotometric study was carried out, for the first time, to investigate the reaction between the vasodilator pentoxifylline hydrochloride (POX) and 1,2-naphthoquinone-4-sulphonate (NQS) reagent. The reaction occurs in alkaline medium to activate the nucleophilic substitution reaction producing an orange-colored product measured spectrophometrically at λmax 472 nm. The variables affecting the reaction were carefully studied and the conditions were optimized. The kinetics of the reaction was investigated and its activation energy was found to be 0.262 cal/mol. Owing to its low activation energy, the reaction proceeded easily and was successfully used for simple and rapid assay of POX. The stoichiometry of the reaction was determined (1:1), and the reaction mechanism was suggested. To develop a high-throughput methodology used in quality control laboratory, a comparative study of the reaction using the conventional spectrophotometric versus microwell assay was applied. Under the optimum reaction conditions, the initial rate and fixed time methods were utilized for constructing the calibration graphs for determination of POX concentrations. The linear range was 10 - 120 μg/ml with good correlation coefficients (0.9987 - 0.9998). The LOD was 2.5 and 3.4 μg/ml for initial rate and fixed time methods, respectively. The intra- and inter-day accuracy and precision of the developed methods were satisfactory, where RSD was ≤3.94%. The present methods have been successfully applied to the determination of POX in its pharmaceutical tablets, and the percentage recovery values were 97.9% - 101.9%. Therefore, we strongly recommend the proposed methods for determination of POX in quality control laboratories.

Prevention of Autoimmune Diabetes by Pentoxifylline is Associated with Target Tissue Modulation of Cytokines and the Expression of Fas-FasL

The effect of Pentoxifylline (PTX) on type 1 diabetes was investigated by means of the studies on the expressions of cytokine mRNA in pancreas and the Fas-FasL on islet cells of NOD mice. NOD mice were treated with PTX from 4-6?wk, and then from 8-12?wk. After treatment, it was found that the incidence of diabetes in NOD mice at ages of 30?wk was reduced to 25% in group of mice treated with PTX, in comparison to 73.3% in case of mice injected with PBS, and the degree of insulitis in the PTX treated mice was lower than that of the PBS injected mice. RT-PCR analysis revealed down-regulatory effect on the expressions of IFN-γ and TNF-α mRNA in PTX treated mice, but there was no any effect on the expression of IL-10. As to the expression of Fas, there was marked decrease in the mean cytoplasmic integral optical density (IOD) in PTX treated mice, but there was little difference between PTX and PBS groups in the expression of FasL. These results indicated that PTX could prevent the development of diabetes in NOD mice, which might be related to the regulation of Th1/Th2 imbalance and the decreased expression of Fas in islet cells.

The effect of pentoxifylline on IL-6 and PDGF expression in human keloid fibroblasts

Objective:The aim of this study was to investigate the effect of different dose of pentoxifylline(PTX)on intedeukin-6(IL-6)and platelet-derived growth factor(PDGF)expression in human normal skin fibroblast(NF)and keloid fibroblast(KF),to explore the pathogenesis of PTX on prevention and treatment of KF.Methods:Human NF and KF were passaged till the 5 th to 7 th generations by tissue block adhering wall method,and then were cultured in vitro with different dose of PTX.Levels of IL-6 and PDGF were detected by ELISA at various periods.Results:(1)Compared with control group,the expressions of IL-6 in NF were significantly inhibited with 0.5 mg/ml PTX for 72 h,1.0 mg/ml and 2.0 mg/ml PTX for 24 h,48 h and 72 h separately(p<.01);The lower expressions of IL-6 were also showed in KF with 0.25 mg/ml PTX for 48 h and 72 h,0.5 mg/ml,1.0 mg/ml and 2.0 mg/ml PTX for 24 h,48 h and 72 h separately(p<.01).(2)After cultured with 0.25 mg/ml PTX for 72 h,0.5 mg/ml,1.0 mg/ml and 2.0 mg/ml PTX for 24 h,48 h and 72 h separately,the expressions of PDGF in NF were decreased significantly compared to the controls(p<.01);The reduced PDGF expressions were also found in KF after cultured with 0.25 mg/ml,0.5 mg/ml,1.0 mg/ml and 2.0 mg/ml PTX for 24 h,48 h and 72 h separately(p<.05).Repeated measures analysis of variance indicated the difference source of cells and doses with statistical significance.Conclusions:The expressions of IL-6 and PDGF in KF were higher than those in NF.PTX plays a notable inhibitory role in the expression of IL-6 and PDGF,which could be used as a promising medicine for Keloid treatment.

Functional protection of pentoxifylline against spinal cord ischemia/reperfusion injury in rabbits： necrosis and apoptosis effects

Background Little is known about neuronal death mechanisms following spinal cord ischemia. The present study aimed to investigate the protective effect of pentoxifylline （PTX） against spinal cord ischemia/reperfusion （I/R） injury. Methods Rabbits sustained spinal cord ischemia following 45 minutes cross-clamping of the infrarenal aorta. Experimental groups were as follows： the first group of animals （sham, n=-8） underwent laparotomy alone and served as the sham group; the second group （I/R, n=20） received carrier （3 ml saline solution） and served as the control group; the third group （PTX-A, n=20） received PTX intravenously 10 minutes prior to ischemia; and the fourth group （PTX-B, n=20） received PTX intravenously at the onset of reperfusion. Rabbits were evaluated for hind-limb motor function with the Tarlov scoring system at 48 hours. Serum was assayed with enzyme-linked immunosorbent assay for tumor necrosis factor α （TNF-α） and spinal cords were harvested for myeloperoxidase （MPO） activity, histopathological analysis, terminal deoxynucleotidyl transferase （TdT）-rnediated dUTP nick end labeling staining, platelet/endothelial ceU adhesion molecule-1 （PECAM-1） and caspase-3 immunohistochemistry, and the number of necrotic and apoptotic neuron were counted and data analyzed at 12, 24, 48 and 72 hours of reperfusion. Spinal cords were studied by electron microscopy. Results Improved Tarlov scores were seen in PTX-treated rabbits as compared with ischemic control rabbits at 48 hours. A significant reduction was found in TNF-α in serum, activity of MPO and immunoreactivity of the PECAM-1 and caspase-3 in PTX-treated rabbits. There were fewer apoptotic neurons than necrotic neurons （P 〈0.05）. A significant decrease in both necrotic and apoptotic neurons was observed in the PTX-treated groups （PTX-A and PTX-B） compared with the I/R group （P 〈0.05）. Both necrotic and apoptotic neurons were found with the electron microscope. Conclusions PTX may induce protection against ischemia injury in the spinal cord, thereby preventing both necrosis and apoptosis. A major mode of cell death in spinal cord ischemia/reperfusion injury is necrosis while apoptosis is not dominant.

Effects of pentoxifylline on Wnt/β-catenin signaling in mice chronically exposed to cigarette smoke

Background Previous discovery that long-term administration of pentoxifylline （PTX） to mice chronically exposed to smoke led to the development of pulmonary fibrosis rather than emphysema initiated our curiosity on whether the Wnt/β-catenin pathway, a set of signaling proteins essential to organ development and lung morphogenesis in particular were activated in the pathogenesis of pulmonary fibrosis. Methods Male BALB/c mice were randomized into four study groups： Group Sm, smoke exposure and taken regular forage; Group PTX, no smoke but taken PTX-rich forage; Group Sm＋PTX, smoke exposure and taken PrX-rich forage; Group control： shamed smoke exposure and taken regular forage. Animals were sacrificed at day 120. Morphometry of the lung sections and the expressions of TGF-β1, hydroxyproline, β-catenin, cyclin D1, T cell factor 1 （Tcf-1） and lymphoid enhancer factor 1 （Lef-1） mRNA, etc, in the lung homogenate or in situ were qualitatively or quantitatively analyzed. Results As expected, smoke exposure along with PTX administration for 120 days, lungs of the mice progressed to be a fibrosis-like phenotype, with elevated fibrosis score （3.9±1.1 vs. 1.7±0.6 in Group Sm, P 〈0.05）. TGF-β1（pg/g） （1452.4±465.7 VS. 818.9±2.02.8 in Group Sm, P 〈0.05） and hydroxyproline （mg/g） （5.6±0.6, vs. 2.4±0.1 in Group Sm, P 〈0.05） were also consistently increased. The upregulation of β-catenin measured either by counting the cell with positive staining in microscopic field （17.4±7.9 vs. 9.9±2.9 in Group Sm, P 〈0.05） or by estimation of the proportion of blue-stained area by Masson＇s trichrome （11.8±5.6 vs. 4.7±4 in Group Sm） in Group SM＋PTX was much more noticeable as than those in Group Sm. The expression of β-catenin measured by positive cell counts was correlated to TGF-β1 concentration in lung tissue （r=0.758, P 〈0.001）. PTX per se caused neither fibrosis nor emphysema though expression of β-catenin and downstream gene cyclin D1 may also be altered by this medication. Conclusions PTX mediated transformation of pulmonary emphysema into pulmonary fibrosis under chronic cigarette smoke exposure is associated with upregulation of β-catenin and elevation of TGF-β1, implying that activation of Wnt/β-catenin signaling may be involved in the pathogenesis of pulmonary fibrosis.

Pentoxifylline attenuates cigarette smoke-induced overexpression of CXCR3 and IP-10 in mice

Background Cigarette smoke-induced emphysema is associated with overexpression of the chemokine receptor CXCR3 and its ligands. Previously, we have demonstrated that pentoxifylline （PTX） alleviated cigarette smoke-induced emphysema. The aim of this study was to determine if the overexpression of CXCR3 and its ligand interferon-inducible protein-10 （IP-10） that was elicited by smoke exposure were attenuated by PTX. Methods （1） The study in vitro： a given number of RAW264.7 macrophages with decreasing concentrations of PTX in the culture medium were challenged with cigarette smoke extract （CSE）; （2） The study in vivo： male BALB/c mice were randomized into four groups, i.e., sham-smoke, smoke only, smoke with 2 mg/kg PTX, and smoke with 10 mg/kg PTX. The smoke exposure time was 90 minutes once a day, 6 days a week for 16 weeks. PTX was given intraperitoneally before each episode of smoke exposure. Interferon （IFN）-y and IP-10 in broncho-alveolar lavage fluid （BALF） and in culture medium were measured by enzyme-linked immunosorbent assay （ELISA）. IP-10 mRNA in lung tissue was assessed by RT-PCR. CXCR3 positive cells in lung sections were visualized by immunochemistry staining. Results Up-regulation of IFN-γ and IP-10 in the culture medium of macrophages elicited by CSE was inhibited by PTX in a dose-dependent manner. Chronic cigarette smoke exposure led to overexpression of IFN-γ and IP-10 in BALF, upregulation of IP-10 mRNA and increased infiltration of CXCR3^＋ cells into lung parenchyma. Administration of PTX decreased the level of IFN-y from （6.26±1.38） ng/ml to （4.43±0.66） ng/ml by low dose PTX or to （1.74±0.28） ng/ml by high dose PTX. IP-10 was reduced from （10.35±1.49） ng/ml to （8.19±0.79） ng/ml by low dose PTX or to （7.51±0.60） ng/ml by high dose PTX. The expression of IP-10 mRNA was also down-regulated （P 〈0.05）. But only with a high dose of PTX was the ratio of CXCR3^＋ cells decreased; 15.2±7.3 vs. 10.4±1.8 （P 〈0.05）. Conclusion PTX attenuates cigarette smoke-induced overexpression of chemokine receptor CXCR3 and its ligand IP-10, which is relevant to its inhibitory effect on pulmonary emphysema.