Effects of pentoxifylline on renal structure after urethral obstruction in rat: A stereological study

Evaluation of therapeutic use of a combination of pentoxifylline and vitamin E in radiation-induced renal fibrosis

Radiation-induced renal fibrosis (RIRF) is a progressive, irreversible condition causing chronic kidney disease. Pentoxifylline (PTX) and vitamin E may mitigate radiation-induced damage and fibrosis. This study assesses their effectiveness. We used four groups, each with six rats: radiation therapy alone (RT-only), radiation therapy plus drug treatment (RT + drug), drug treatment alone (drug-only), and a control group. Rats were monitored for three months, with weight measurements every four weeks. Afterward, rats were analyzed biochemically and histologically, with blood and tissue samples taken for statistical comparison. No significant differences in serum creatinine levels and body weight were observed. RT-only group had more severe kidney tubule effects. Histomorphological, immunohistochemical, and TUNEL analyses showed significant RIRF mitigation in the RT + drug group. Our study highlighted molecular pathways (SMAD, TGF-beta, VEGF) and histological markers (collagens, a-SMA, fibronectin, metalloproteinases) associated with RIRF. PTX and vitamin E reduced ionizing radiation's impact on renal cells and mitigated radiation-induced kidney fibrosis. Further human studies are needed to confirm these findings.

Comparison between combination of tamsulosin and Pentoxifylline versus tamsulosin alone in the treatment of lower urinary tract symptoms due to benign prostate hyperplasia: A preliminary study

BACKGROUND

In older adults, bladder outlet obstruction (BOO) is prevalent, primarily due to benign prostatic hyperplasia (BPH). These patients' lower urinary tract symptoms can be treated surgically and with medical therapy. Compared to standard treatment with tamsulosin, Pentoxifylline, a phosphodiesterase inhibitor, could benefit patients with BOO due to its properties on microcirculatory blood flow and oxygenation of ischemic tissues. Hence, this trial intended to study the efficacy of Pentoxifylline combined with tamsulosin in treating BOO patients.

MATERIALS AND METHODS

This randomized, double-blind clinical trial recruited 60 patients with BPH from a single center in 2022. Upon consent of patients meeting the eligibility criteria, they were randomly allocated to intervention (Pentoxifylline + tamsulosin) and control (placebo + tamsulosin) groups. The patients were evaluated for international prostate symptom score (IPSS), quality of life (QoL), maximum urinary flow rate (Qmax ) by uroflowmetry, and post-void residual volume (PVR) by abdominal sonography at the onset of the study and after the 12th week.

RESULTS

Patients who used the combination therapy had significantly better results of prostate symptoms and quality of life improvement (IPSS: -36.6%, QoL: -45.3%) compared to patients who received tamsulosin alone (IPSS: -21.2%, QoL: -27.7%) (p < .001). Also, this study shows that the improvement in maximum urinary flow rate and residual volume by combination therapy is significantly higher (Qmax : +42.5%, PVR: -42.6%) compared to monotherapy (Qmax : +25.1%, PVR: -26.1%) (p < .001).

CONCLUSION

When combined with tamsulosin, Pentoxifylline could significantly improve the lower urinary symptoms of BPH patients. It is well tolerated, and the treatment outcomes are better in patients who receive the combination of Pentoxifylline and tamsulosin than those who only receive tamsulosin.

L-glutamine supplementation reduced morphological damage in the renal glomerulus of rats with Walker-256 tumor

PURPOSE

To evaluate the effects of the experimental subcutaneous Walker-256 tumor and L-glutamine supplementation, an antioxidant, on the glomerular morphology of rats.

METHODS

Twenty Wistar rats were distributed into four groups (n = 5): control (C); control treated with 2% L-glutamine (CG); rats with Walker-256 tumor (WT); and rats with Walker-256 tumor treated with 2% L-glutamine (WTG). Renal histological samples were submitted to periodic acid-Schiff and Masson's Trichrome staining to analyze glomerular density, morphometry of glomerular components and glomerulosclerosis; and to immunohistochemistry for fibroblast growth factor-2 (FGF-2).

RESULTS

WT showed 50% reduction in body mass gain and cachexia index > 10%, while WTG demonstrated reduction in cachexia (p < 0.05). WT revealed reduction of glomerular density, increase in the glomerular tuft area, mesangial area, matrix in the glomerular tuft, decrease in the urinary space and synechia, and consequently higher glomerulosclerosis (p < 0.05). L-glutamine supplementation in the WTG improved glomerular density, and reduced glomerular tuft area, urinary space, mesangial area, and glomerulosclerosis compared to WT(p < 0.05). WT showed higher collagen area and FGF-2 expression compared to C (p < 0.05). WTG presented lower collagen fibers and FGF-2 expression compared to WT (p < 0.05).

CONCLUSIONS

L-glutamine supplementation reduced cachexia and was beneficial for glomerular morphology of the rats, as well as it reduced kidney damage and improved the remaining glomeruli morphology.

Progress in drug delivery system for fibrosis therapy

Fibrosis is a necessary process in the progression of chronic disease to cirrhosis or even cancer, which is a serious disease threatening human health. Recent studies have shown that the early treatment of fibrosis is turning point and particularly important. Therefore, how to reverse fibrosis has become the focus and research hotspot in recent years. So far, the considerable progress has been made in the development of effective anti-fibrosis drugs and targeted drug delivery. Moreover, the existing research results will lay the foundation for more breakthrough delivery systems to achieve better anti-fibrosis effects. Herein, this review summaries anti-fibrosis delivery systems focused on three major organ fibrotic diseases such as liver, pulmonary, and renal fibrosis accompanied by the elaboration of relevant pathological mechanisms, which will provide inspiration and guidance for the design of fibrosis drugs and therapeutic systems in the future.

Repurposing Pentoxifylline for the Treatment of Fibrosis: An Overview

Fibrosis is a potentially debilitating disease with high morbidity rates. It is estimated that half of all deaths that occur in the USA are attributed to fibrotic disorders. Fibrotic disorders are characterized primarily by disruption in the extracellular matrix deposition and breakdown equilibrium, leading to the accumulation of excessive amounts of extracellular matrix. Given the potentially high prevalence of fibrosis and the paucity of agents currently available for the treatment of this disease, there is an urgent need for the identification of drugs that can be utilized to treat the disease. Pentoxifylline is a methylxanthine derivative that is currently approved for the treatment of vascular diseases, in particular, claudication. Pentoxifylline has three main properties: improving the rheological properties of blood, anti-inflammatory, and antioxidative. Recently, the effectiveness of pentoxifylline in the treatment of fibrosis via attenuating and reversing fibrotic lesions has been demonstrated in several clinical trials and animal studies. As a result of the limited availability of antifibrotic agents in the long-term treatment of fibrosis that can attenuate and even reverse fibrotic lesions effectively, it would be of particular importance to consider the potential clinical utility of pentoxifylline in the treatment of fibrosis. Thus, this paper discusses the evolving roles of pentoxifylline in the treatment of different types of fibrosis.

Cyclic nucleotide signalling in kidney fibrosis

Kidney fibrosis is an important factor for the progression of kidney diseases, e.g., diabetes mellitus induced kidney failure, glomerulosclerosis and nephritis resulting in chronic kidney disease or end-stage renal disease. Cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) were implicated to suppress several of the above mentioned renal diseases. In this review article, identified effects and mechanisms of cGMP and cAMP regarding renal fibrosis are summarized. These mechanisms include several signalling pathways of nitric oxide/ANP/guanylyl cyclases/cGMP-dependent protein kinase and cAMP/Epac/adenylyl cyclases/cAMP-dependent protein kinase. Furthermore, diverse possible drugs activating these pathways are discussed. From these diverse mechanisms it is expected that new pharmacological treatments will evolve for the therapy or even prevention of kidney failure.

Stereological comparison of the effects of pentoxifylline, captopril, simvastatin, and tamoxifen on kidney and bladder structure after partial urethral obstruction in rats

Purpose

Limited studies have shown antifibrotic effects of pentoxifylline, captopril, simvastatin, and tamoxifen. No comparisons are available of the effects of these drugs on prevention of renal and bladder changes in partial urethral obstruction (PUO).

Materials and Methods

The rats were divided into six groups (n=7). The sham-operated rats (group I) only underwent laparotomy and did not receive any treatments. The PUO groups (group II-VI) received normal saline (PUO+NS), pentoxifylline (100 mg/kg/d; PUO+PEN), captopril (35 mg/kg/d; PUO+CAP), simvastatin (15 mg/kg/d; PUO+SIM), or tamoxifen (10 mg/kg/d; PUO+TAM) by gavage for 28 days. Then, the volume and/or length of the kidney components (tubules, vessels, and fibrous tissue) and the bladder components (epithelial and muscular layers, fibrous tissue, fibroblast and fibrocyte number) were quantitatively evaluated on the microscopic sections by use of stereological techniques.

Results

The volume of renal and bladder fibrosis was significantly ameliorated in the PUO+PEN group, followed by the PUO+CAP, PUO+SIM, and PUO+TAM groups. Also, the volume and length of the renal tubules and vessels and bladder layers were more significantly protected in the PUO+PEN group, followed by the PUO+CAP, PUO+SIM, and PUO+TAM groups.

Conclusions

Treatment of PUO with PEN was more effective in the prevention of renal and bladder fibrosis and in the preservation of renal and bladder structures.