Dexamethasone and losartan combination treatment protected cigarette smoke-induced COPD in rats

Chronic Obstructive Pulmonary Disease (COPD) is a dangerous prevalent smoking-related disease characterized by abnormal inflammation and oxidative stress and expected to be the third cause of death in the world next decade. Corticosteroids have low effects in decreasing numbers of inflammatory mediators specifically in long-term use. Our study designed to investigate the possible protective effects of combined dexamethasone (Dex) (2mg/kg) and losartan (Los) (30mg/kg angiotensin receptor blocker, it possesses antioxidant and anti-inflammatory properties in lung injury in mice) against cigarette -smoke (CS) induced COPD in rats compared with dexamethasone and losartan. Male Sprague Dawley rats (N = 40) divided into five groups (n = 8): control group, CS group, Dex group, Los group, and Dex +Los group. COPD induced in rats by CS exposure twice daily for 10 weeks. After the specified treatment period, bronchoalveolar lavage fluid (BALF) and lung tissue were collected for measurement of SOD, NO, MDA, ICAM-, MMP-9, CRP, NF-κB and histopathology scoring. Our results indicated that Los+Dex significantly prevent CS-induced COPD emphysema, congested alveoli, and elevation of lung injury parameters in BALF. They also showed a significant decrease in MDA, ICAM-1, MMP-9, CRP, and NF-κB and a significant increase in SOD and NO. In conclusion, adding Los to Dex potentiating their activity in inhibition the progression of COPD based on its activity on oxidative stress, inflammation, and NF-κB protein expression.

The potential beneficial effects of sildenafil and diosmin in experimentally-induced gastric ulcer in rats

Objectives

research in the treatment of gastric ulcer has involved the investigation of protective drugs. These drugs may be used as adjacent therapy with the traditional pharmacologic treatment of peptic ulcer. The present study is designed to investigate the gastro protective effects of diosmin (DIO), sildenafil (SILD) and their combinations with ranitidine (RANT) against indomethacin (INDO)-induced gastric ulcer in rats. Additionally, the potential mechanisms of their effect are addressed.

Methods

DIO (100 mg/kg) and SILD (10 mg/kg) were administered by oral route for seven days prior to ulcer induction. Moreover, other rats were treated with RANT (50 mg/kg) not only to compare efficiency of the medications but also, to help clarify potential mechanisms of their effect. Following, after 24 h of fasting, INDO (100 mg/kg) was administered for induction of gastric ulcer. Furthermore, rats in each group were sacrificed 4 h later. Biochemical analysis of DIO, SILD, RANT and their combinations pre-treated host tissues demonstrated reduction in tumor necrosis factor (TNF)-α and malondialdehyde (MDA) contents and concomitant increase in gastric pH, nitric oxide (NO) and reduced glutathione (GSH) contents.

Result

It is observed, that SILD and DIO pre-treatment showed non-significant effect on gastric juice PH. However, their combinations with RANT is superior to using RANT alone. In addition, the results revealed, that combinations of (RANT and SILD) and (RANT and DIO) showed the highest increase in gastric tissue NO levels. But, these two combinations achieved the lowest MDA levels relative to the control (INDO) group. Despite, all groups displayed non-significant effect on reduced GSH content, (RANT and SILD) group increased GSH concentration by 39.75% relative to INDO group. In addition, DIO, RANT and (RANT and DIO) pre-treatment have anti-apoptotic activity on gastric mucosa. On the other hand, SILD did not affect caspase-3 immunostaining. These results are confirmed by histopathological findings.

Conclusion

The work outcomes provide a new gastro protective agents in clinical gastropathy. So, this study not only provides an efficient way for peptic ulcer protection, but also it may be considered for future studies in ulcer healing and gastric cancer.

Anticancer effect of metformin against 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine-induced rat mammary carcinogenesis is through AMPK pathway and modulation of oxidative stress markers

OBJECTIVES

Metformin, the type 2 anti-diabetes medication, showed antitumor activity both in vivo and in vitro. This study was carried out to investigate the mechanisms behind the metformin anticancer effect against 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced mammary carcinogenesis in female Sprague-Dawley rats.

METHODS

Rats received 10 doses of PhIP (75 mg/kg, p.o., days 1-5 and 8-12). Then, rats were treated with metformin for 26 weeks at a dose of 2 mg/ml in drinking water.

KEY FINDINGS

Metformin antitumor effect was mediated by increasing the adenosine monophosphate protein kinase (AMPK) activity, liver kinase B1, and decreasing the aromatase and insulin levels compared with the PhIP-administered group. Also, this treatment resulted in a significant decrease in mammary tissue oxidative stress markers and serum lipid profile. In parallel, mammary gland tumors found in PhIP+metformin group were all histologically benign included only (hyperplasia). However, most of the mammary gland tumors found in PhIP group were histologically malignant.

CONCLUSIONS

These results showed that metformin antitumor effect was mediated through AMPK pathway, reducing oxidative stress and serum lipid levels. This study supports the potential benefit of using metformin as adjuvant therapy during breast cancer treatment.

Oxamate potentiates taxol chemotherapeutic efficacy in experimentally-induced solid ehrlich carcinoma (SEC) in mice

Several human cancers including the breast display elevated expression of Lactate dehydrogenase-A (LDH-A), the enzyme that converts pyruvate to lactate and oxidizes NADH to NAD⁺. Indeed, tumor lactate levels correlate with increased metastasis, tumor recurrence, and poor outcome. Lactate also plays roles in promoting tumor inflammation and as a signaling molecule that stimulates tumor angiogenesis. Because of its essential role in cancer metabolism, LDH-A has been considered as a potential target for combination cancer therapy. Therefore, the current study investigated the possible anti-tumor effect of LDH inhibitor (oxamate) in a murine model of breast cancer [Solid Ehrlich Carcinoma (SEC)], alone and in combination with Taxol chemotherapy. The potential underlying mechanisms were also investigated. The results indicated that oxamate induced significant anti-tumor activity against the SEC. Mechanistically, the combination treatment was more efficient than paclitaxel monotherapy in reducing ATP, MDA, TNF-α and Il-17 contents in SEC. Moreover, the apoptotic and anti-angiogenic effects of the combination treatment were triggered more efficiently as compared to paclitaxel monotherapy, Therefore, oxamate may represent a promising agent that enhance the antitumor activity of paclitaxel.

PPARγ-dependent anti-tumor and immunomodulatory actions of pioglitazone

Peroxisome proliferator-activated receptor-γ (PPARγ) has been reported to play important roles in carcinogenesis. The current study was carried out to assess the possible anti-tumor effects of pioglitazone (PIO), a PPARγ agonist, in a mouse mammary carcinoma model, i.e. a solid Ehrlich carcinoma (SEC). Effects of PIO on tumor-induced immune dysfunction, and the possibility that PIO may modulate the anti-tumor and immunomodulatory effects of doxorubicin (DOX) were also studied. The effects in tumor-bearing hosts of several doses of PIO (100 mg/kg, per os), with and without the added presence of DOX (2 mg/kg, IP), was investigated in vivo; end-points evaluated included assessment of tumor volume, splenic lymphocyte profiles/functionality, tumor necrosis factor (TNF)-α content, as well as apoptosis and expression of nuclear factor-κB (NF-κB) among the tumor cells. The data indicate that PIO induced significant anti-tumor activity against the SEC. PIO treatments also significantly mitigated both tumor- and doxorubicin-induced declines in immune parameters assessed here. Moreover, PIO led to decreased NF-κB nuclear expression, and, in doing so, appeared to chemo-sensitize these tumor cells to DOX-induced apoptosis. All pioglitazone-studied effects were antagonized by GW9662, a selective PPARγ antagonist.