2-Methoxyestradiol inhibits carotid artery intimal hyperplasia induced by balloon injury via inhibiting JAK/STAT axis in rats.

Intimal hyperplasia (IH) is a common complication of vascular interventional procedures that leads to narrowing of the vessel lumen. 2-Methoxyestradiol (2ME), an estrogen metabolite, has numerous pharmacological actions, including vasoprotective and antiproliferative activities. The present study aimed to evaluate the potential of 2ME, prepared as a self-nanoemulsifying drug delivery system (SNEDDS), to inhibit IH induced by balloon injury (BI) in the rat carotid artery. The prepared 2ME SNEDDS had a particle size of 119 ± 2.3 nm and a zeta potential of -7.1 ± 1.4 mV. Animals were divided into 5 groups, namely control, sham, BI, BI + 2ME (100 µg/kg), and BI + 2ME (250 µg/kg). The obtained data indicated that 2ME significantly inhibited IH as indicated by the histological and morphometric assessment of the intima, media and lumen areas. This was associated with enhanced expression of Bax and inhibited expression of Bcl2 mRNA. Furthermore, 2ME exhibited significant antioxidant properties as evidenced by prevention of malondialdehyde accumulation as well as superoxide dismutase and catalase enzymatic exhaustion. In addition, 2ME showed significant anti-inflammatory actions as it significantly inhibited vascular content of interleukin-6, tumor necrosis factor-alpha, and nuclear factor-κB. The observed vasoprotective activities of 2ME were accompanied by inhibition of Janus kinase/signal transducers and activators of transcription (JAK/STAT) protein expression. In conclusion, this study revealed that 2ME ameliorates balloon injury-induced IH in rats via suppressing JAK/STAT axis. This may help to develop new strategies to combat IH.

2-Methoxyestradiol Attenuates Testosterone-Induced Benign Prostate Hyperplasia in Rats through Inhibition of HIF-1α/TGF-ß/Smad2 Axis.

Benign prostatic hyperplasia (BPH) is a common disorder in the male population. 2-Methoxyestradiol (2ME) is an end metabolite of estrogens with pleiotropic pharmacological properties. This study aimed to explore the potential ameliorative effects of 2ME against testosterone-induced BPH in rats. 2-Methoxyestradiol (50 and 100 mg/kg, dissolved in DMSO) prevented the rise in prostatic index and weight in comparison to testosterone-alone-treated animals for 2 weeks. Histological examination indicated that 2ME ameliorated pathological changes in prostate architecture. This was confirmed by the ability of 2ME to decrease the glandular epithelial height when compared to the testosterone group. Also, 2ME improved testosterone-induced oxidative stress as it inhibited the rise in lipid peroxide content and the exhaustion of superoxide dismutase (SOD) activity. The beneficial effects of 2ME against the development of BPH were substantiated by assessing proliferation markers, preventing the rise in cyclin D1 protein expression and enhancing Bax/Bcl2 mRNA ratio. It significantly reduced prostate content of tumor necrosis factor α (TNF-α), interleukin-1ß (IL-1ß), nuclear factor κB (NF-κB), and transforming growth factor ß (TGF-ß). In addition, 2ME reduced hypoxia-inducible factor 1-α (HIF-1α) and phospho-Smad2 (p-Smad2) protein expression compared to the testosterone group. In conclusion, 2ME attenuates experimentally induced BPH by testosterone in rats through, at least partly, inhibition of HIF-1α/TGF-ß/Smad2 axis.

Anti-angiogenic agents for the treatment of solid tumors: Potential pathways, therapy and current strategies - A review.

Recent strategies for the treatment of cancer, other than just tumor cell killing have been under intensive development, such as anti-angiogenic therapeutic approach. Angiogenesis inhibition is an important strategy for the treatment of solid tumors, which basically depends on cutting off the blood supply to tumor micro-regions, resulting in pan-hypoxia and pan-necrosis within solid tumor tissues. The differential activation of angiogenesis between normal and tumor tissues makes this process an attractive strategic target for anti-tumor drug discovery. The principles of anti-angiogenic treatment for solid tumors were originally proposed in 1972, and ever since, it has become a putative target for therapies directed against solid tumors. In the early twenty first century, the FDA approved anti-angiogenic drugs, such as bevacizumab and sorafenib for the treatment of several solid tumors. Over the past two decades, researches have continued to improve the performance of anti-angiogenic drugs, describe their drug interaction potential, and uncover possible reasons for potential treatment resistance. Herein, we present an update to the pre-clinical and clinical situations of anti-angiogenic agents and discuss the most recent trends in this field.

Icariin protects against thioacetamide-induced liver fibrosis in rats: Implication of anti-angiogenic and anti-autophagic properties.

BACKGROUND: Liver fibrosis is a major health problem. The current study evaluated the potential of icariin (ICA) to guard against thioacetamide (TAA)-induced liver fibrosis in rats. METHODS: Four groups of male rats were treated as follows: group 1 was the control group, group 2 was given TAA (200mg/kg), group 3 was administered ICA (50mg/kg) and TAA (200mg/kg), and group 4 was given ICA (50mg/kg) alone. Animal treatment was continued for four weeks. RESULTS: Co-administration of ICA guarded against TAA hepatotoxicity as indicated by significant inhibition in the rise of serum ALT and AST activities and albumin concentrations. This was accompanied by inhibition of reduced glutathione depletion, superoxide dismutase exhaustion, and lipid peroxide accumulation. In addition, ICA inhibited the pathological alterations in liver architecture induced by TAA. The antifibrotic activity of ICA was verified by reduced hepatic collagen deposition in liver sections stained with Masson's trichrome and hepatic Col-1α mRNA and hydroxyproline contents compared to the TAA-treated group. The antiangiogenic activity of ICA was evidenced by lowered levels of mRNA of Ang-1 and protein expression of VEGF, PDGF-ß, and CTGF immunohistochemically. Further, the anti-autophagic property of ICA was evidenced by amelioration of the decrease in mTOR and p70S6 kinase expression and an increase in TLR4, NFκB, IL1-ß, and COX-2 immunohistochemically. Moreover, ICA antagonized the increase in HMGB1, TGF-ß, and Beclin-1 and the decrease in BAMBI hepatic mRNA levels. CONCLUSIONS: ICA inhibits TAA-induced liver fibrosis in rats, possibly via inhibition of angiogenesis and autophagy.

Gingerol protects against experimental liver fibrosis in rats via suppression of pro-inflammatory and profibrogenic mediators.

6-Gingerol (Gin) is known to possess hepatoprotective effects. Liver fibrosis is a major health concern that results in significant morbidity and mortality. There is no FDA-approved medication for liver fibrosis. The present work aimed at exploring the beneficial effects of Gin against liver fibrosis in rats. Experimental fibrosis was induced by challenging animals with CCl4 for 6 weeks. Gin significantly ameliorated the increase in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, albumin, total cholesterol (TC) and triglyceride (TG) concentrations, and liver index. These effects were confirmed by light and electron microscopic examinations. The antifibrotic effects were confirmed by examining Masson trichrome-stained liver sections which indicated reduced collagen deposition in Gin-treated animals. Further, Gin administration hampered alpha-smooth muscle actin (α-SMA) expression and significantly reduced hepatic content of transforming growth factor-beta (TGF-ß). Also, Gin elicited profound antioxidant actions as indicated by preventing reduced glutathione (GSH) depletion and lipid peroxide accumulation. The observed antifibrotic activities involved decreased production of nuclear factor κB (NF-κB), tumor necrosis factor alpha (TNF-α), expression of toll-like receptor 4 (TLR4), intercellular adhesion molecule (ICAM), and vascular cell adhesion molecule (VCAM). Involvement of Gin anti-inflammatory activity was verified by the decreased expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in livers of animals treated with Gin. Thus, it can be concluded that Gin protects against CCl4-induced liver fibrosis in rats. This can be ascribed, at least partly, to its antioxidant, anti-inflammatory effects as well as the inhibition of NF-κB/TLR-4 expression.

Anti-inflammatory activity of selected plants from Saudi Arabia.

Thirteen selected Saudi Arabian plants, belonging to seven different families, were tested for possible anti-inflammatory activity using the carrageenin-induced paw edema model in rats. The methanolic extracts of Vernonia schimperi, Trichodesma trichodesmoides var. tomentosum, and Anabasis articulata exhibited the highest anti-inflammatory activity. The active extracts were further subjected to fractionation with chloroform, ethyl acetate, and n-butanol and tested together with their mother liquor for their anti-inflammatory activity in the same rat model. The most potent fractions were the n-butanol fractions of Anabasis articulata and Vernonia shimperi and the aqueous mother liquor of Trichodesma trichodesmoides. Nevertheless, the three potent methanolic extracts showed higher anti-inflammatory activities than their individual fractions. The antioxidant properties were assessed by their in vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activities. It was concluded that the anti-inflammatory activity is dependent, at least in part, on the reduction of prostaglandin (PGE2) and tumour necrosis factor-alpha (TNF-alpha) levels and cyclooxygenase-2 (COX-2) activity.

Evaluation of the potential cardioprotective activity of some Saudi plants against doxorubicin toxicity.

Doxorubicin (DOX) is an anthracycline antibiotic widely used as a chemotherapeutic agent in the treatment of several tumours. However, its cardiac toxicity limits its use at maximum therapeutic doses. Most studies implicated increased oxidative stress as the major determinant of DOX cardiotoxicity. The local Saudi flora is very rich in a variety of plants of quite known folkloric or traditional medicinal uses. Tribulus macropterus Boiss., Olea europaea L. subsp. africana (Mill.) P. S. Green, Tamarix aphylla (L.) H. Karst., Cynomorium coccineum L., Cordia myxa L., Calligonum comosum L' Hér, and Withania somnifera (L.) Dunal are Saudi plants known to have antioxidant activities. The aim of the current study was to explore the potential protective effects of methanolic extracts of these seven Saudi plants against DOX-induced cardiotoxicity in rats. Two plants showed promising cardioprotective potential in the order Calligonum comosum > Cordia myxa. The two plant extracts showed potent in vitro radical scavenging and antioxidant properties. They significantly protected against DOX-induced alterations in cardiac oxidative stress markers (GSH and MDA) and cardiac serum markers (CK-MB and LDH activities). Additionally, histopathological examination indicated a protection against DOX-induced cardiotoxicity. In conclusion, C. comosum and C. myxa exerted protective activity against DOX-induced cardiotoxicity, which is, at least partly, due to their antioxidant effect.

Anti-inflammatory and antiproliferative activities of date palm pollen (Phoenix dactylifera) on experimentally-induced atypical prostatic hyperplasia in rats.

BACKGROUND: Atypical prostatic hyperplasia (APH) is a pseudoneoplastic lesion that can mimic prostate adenocarcinoma because of its cytologic and architectural features. Suspension of date palm pollen (DPP) is an herbal mixture that is widely used in folk medicine for male infertility. The aim of the present study was to evaluate the effect of DPP suspension and extract on APH-induced rats. METHODS: APH was induced in adult castrated Wistar rats by both s.c. injection of testosterone (0.5 mg/rat/day) and smearing citral on shaved skin once every 3 days for 30 days. Saw palmetto (100mg/kg), DPP suspension (250, 500 and 1000 mg/kg), and lyophilized DPP extract (150,300 and 600 mg/kg) were given orally daily for 30 days. All medications were started 7 days after castration and along with testosterone and citral. RESULTS: The histopathological feature in APH-induced prostate rats showed evidence of hyperplasia and inflammation. Immunohistochemical examination revealed that the expressions of IL-6, IL-8, TNF-α, IGF-1 and clusterin were increased, while the expression of TGF-ß1 was decreased that correlates with presence of inflammation. Moreover, histopathological examination revealed increased cellular proliferation and reduced apoptosis in ventral prostate. Both saw palmetto and DPP treatment has ameliorated these histopathological and immunohistochemical changes in APH-induced rats. These improvements were not associated with reduction in the prostatic weight that may be attributed to the persistence of edema. CONCLUSION: DPP may have a potential protective effect in APH-induced Wistar rats through modulation of cytokine expression and/or upregulation of their autocrine/paracrine receptors.

Changes in nitric oxide and free radical levels in rat gastrocnemius muscle during contraction and fatigue.

1. The ratio of nitric oxide (NO) to free radicals is critical during skeletal muscle contraction. Changes in this ratio have been suggested to play a role in muscle fatigue. 2. The aim of the present study was to investigate the changes in NO and free radicals during tetanic and subtetanic contraction and fatigue in the gastrocnemius muscle of adult male Wistar rats. 3. Rats were subjected to either low- or high-frequency stimulation (10 and 100 Hz, respectively) of the right gastrocnemius muscle. Both groups were further subdivided into untreated (0.9% NaCl solution), N(G) -nitro-L-arginine methyl ester (L-NAME)-treated and reduced glutathione (GSH)-treated groups. Rats were administered their treatments intraperitoneally 30 min prior to electrical stimulation. 4. Levels of both NO and lipid peroxides increased significantly during peak force contraction for either type of contractions, with a more significant response during subtetanic contraction. Treatment with L-NAME significantly reduced the maximal force and this effect was more marked in the low frequency-stimulated group. Although peroxides levels were reduced by GSH, it had no significant effect on force production. In L-NAME-treated rats, the onset of 50% fatigue was accelerated with a significant increase in peroxides levels, whereas the opposite effects were observed after GSH treatment. 5. Current results reflect the importance of endogenous NO, as an anti-oxidant, in aiding muscle performance by overcoming oxidative stress during fatigue. They provide a possible explanation as to why patients with myopathies like Duchenne muscular dystrophy, in which dystrophin is lacking suffer from muscle weakness and fatigue easily.

Protective effect of bilberry (Vaccinium myrtillus) against doxorubicin-induced oxidative cardiotoxicity in rats.

BACKGROUND: Doxorubicin (DOX) is a commonly used chemotherapeutic agent. It is associated with serious dose-limiting cardiotoxicity, which is at least partly caused by generation of reactive oxygen species (ROS). Supplementations with bilberries were effective in reducing oxidative stress in many tissue injuries due their high content of antioxidants. The present study investigated the potential protective effect of bilberry extract against DOX-induced cardiotoxicity in rats. MATERIAL/METHODS: Rats were treated orally with a methanolic extract of bilberry for 10 days. DOX was injected intraperitoneally on day 7. Twenty-four hours after the last bilberry administration, rats were subjected to ECG study. Blood was then withdrawn and cardiac tissues were dissected for assessment of oxidative stress and cardiac tissue injury. Cardiac tissues were also subjected to histopathological examination. RESULTS: Bilberry extract significantly inhibited DOX-provoked reduced glutathione depletion and accumulation of oxidized glutathione, malondialdehyde and protein carbonyls in cardiac tissues. This was accompanied by significant amelioration of reduced cardiac catalase, superoxide dismutase, and glutathione peroxidase activities; and increased cardiac myeloperoxidase activity in response to DOX challenge. Pretreatment with bilberry significantly guarded against DOX-induced increase in serum activities of lactate dehydrogenase, creatine phosphokinase and creatine kinase-MB, as well as the level of troponin I. Bilberry alleviated ECG changes in rats treated with DOX and attenuated its pathological changes. CONCLUSIONS: Bilberry protects against DOX-induced cardiotoxicity in rats. This can be attributed, at least in part, to its antioxidant activity.

Cranberry (Vaccinium macrocarpon) protects against doxorubicin-induced cardiotoxicity in rats.

Doxorubicin (DOX) is a widely used cancer chemotherapeutic agent. However, it generates free oxygen radicals that result in serious dose-limiting cardiotoxicity. Supplementations with berries were proven effective in reducing oxidative stress associated with several ailments. The aim of the current study was to investigate the potential protective effect of cranberry extract (CRAN) against DOX-induced cardiotoxicity in rats. CRAN was given orally to rats (100mg/kg/day for 10 consecutive days) and DOX (15mg/kg; i.p.) was administered on the seventh day. CRAN protected against DOX-induced increased mortality and ECG changes. It significantly inhibited DOX-provoked glutathione (GSH) depletion and accumulation of oxidized glutathione (GSSG), malondialdehyde (MDA), and protein carbonyls in cardiac tissues. The reductions of cardiac activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione reductase (GR) were significantly mitigated. Elevation of cardiac myeloperoxidase (MPO) activity in response to DOX treatment was significantly hampered. Pretreatment of CRAN significantly guarded against DOX-induced rise of serum lactate dehydrogenase (LDH), creatine phosphokinase (CK), creatine kinase-MB (CK-MB) as well as troponin I level. CRAN alleviated histopathological changes in rats' hearts treated with DOX. In conclusion, CRAN protects against DOX-induced cardiotoxicity in rats. This can be attributed, at least in part, to CRAN's antioxidant activity.

Angiotensin-converting enzyme inhibition and angiotensin AT(1)-receptor antagonism equally improve doxorubicin-induced cardiotoxicity and nephrotoxicity.

Doxorubicin (Dox) is a potent anticancer agent; its clinical use is limited for its marked cardiotoxicity and nephrotoxicity. The present study investigated the possible protective effect of telmisartan, an angiotensin AT(1)-receptor blocker versus captopril, an angiotensin-converting enzyme inhibitor, on Dox-induced cardiotoxicity and nephrotoxicity in rats. Rats were allocated into four groups. Control group, Dox group, Dox+telmisartan group, and Dox+captopril group. Cardiotoxicity and nephrotoxicity were assessed biochemically and histopathologically. Frozen heart and kidney specimens were used for estimation of lipid peroxides product (MDA), reduced glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) and nitric oxide (NO). Expression of induced nitric oxide synthase (iNOS) was detected by immunohistochemistry. Coadministration of either telmisartan or captopril with Dox equally decreased the biochemical markers of both cardiotoxicity (LDH and CK-MP) and nephrotoxicity (urea and creatinine). Both telmisartan and captopril attenuated the effects of Dox on oxidative stress parameters and NO. Histopathologically, coadministration of either drug with Dox was able to attenuate Dox-induced myocardial fibrosis and renal tubular damage. Immunohistochemistry, expression of iNOS was increased in both cardiac and renal tissues. Both telmisartan and captopril significantly and equally attenuated the effect of Dox on all measured parameters. These results suggested that telmisartan has protective effects equal to that of captopril against Dox-induced cardiotoxicity and nephrotoxicity; implying that angiotensin II pathway plays a role in Dox-induced cardiac and renal damage. The protective effect of either drug relies, at least in part, on their antioxidant effects and decreased the expression of iNOS.

Melatonin protects against hydrogen peroxide-induced gastric injury in rats.

1. Melatonin (MT) is a pineal hormone that is also abundant in the gut and has a well known role in scavenging oxygen free radicals. The aim of the present study was to evaluate the potential protective effects of MT against H(2)O(2)-induced gastric lesions in rats. 2. An experimental model of gastric ulceration was established in rats using 15% H(2)O(2). Melatonin (12.5, 25 or 50 mg/kg, intagastrically) was administered to rats 30 min before H(2)O(2) challenge. 3. Intragastric administration of H(2)O(2) resulted in haemorrhagic lesions in the fundic area of the stomach. Furthermore, H(2)O(2) induced gastric oxidative stress, as indicated by depletion of reduced glutathione (GSH), inhibition of glutathione peroxidase (GPx) activity and elevation of malonedialdehyde (MDA) levels. These effects were accompanied by decreased gastric tissue levels of prostaglandin (PG) E(2) and nitric oxide (NO), as well as increased levels of tumour necrosis factor (TNF)-alpha. Administration of MT (12.5, 25 or 50 mg/kg) 30 min before H(2)O(2) significantly attenuated the development of gastric lesions in a dose-dependent manner. The protective effects of MT were accompanied by significant inhibition of the H(2)O(2)-induced reduction in gastric content of GSH and GPx activity and elevation in MDA levels. Furthermore, MT antagonized H(2)O(2)-induced reduction of gastric PGE(2) and NO levels and elevation of TNF-alpha. 4. In conclusion, MT protects rat gastric mucosa against H(2)O(2)-induced damage. The observed protective effects of MT can be attributed, at least in part, to its anti-oxidant properties, preservation of PGE(2) and NO levels, as well as inhibition of TNF-alpha induction in gastric tissues.