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Purpose: To study the effect of aqueous propolis extract (AEP) against indomethacin (Indo)-induced gastric ulcers in irradiated and non-irradiated rats. Materials and methods: Animals were irradiated at different radiation dose levels before the induction of ulcers. AEP was injected orally 1 hour before induction of gastric ulcers and the effects compared with those of lansoprazole (Lanso), which was used as a reference anti-ulcerogenic drug. Results: Pretreatment of rats, either irradiated or non-irradiated, with AEP effectively protected against Indo-induced gastric ulceration. This was associated with a reduction in acid output and peptic activity and an increase in the secretion of mucin. The mucosal prostaglandin E2 (PGE2) level was also increased. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) were suppressed to the same extent after treatment. Both propolis and Lanso were effective in reducing the number of gastric lesions as well as the plasma level of malondialdehyde (MDA). Conclusions: These findings indicate that the gastroprotective effect of AEP could be of value in the management of excessive gastric damage induced by radiation exposure. [ABSTRACT FROM AUTHOR]

Purpose: Cartilage degradation usually results as a consequence of inflammatory processes in the joints. To study this phenomenon experimentally, adjuvant-induced arthritis ((AIA)) was used as a model of chronic inflammation under the influence of irradiation. The potential chondroprotective effect of 13%% aqueous extract of propolis ((AEP)) in arthritic rats was investigated. Materials and methods: The influence of whole body irradiation on the arthritic inflammatory response was investigated by subjecting rats to a Gamma source before the induction of arthritis. 13%% AEP was injected intraperitoneally in a dose of 5 ml//kg and diclofenac was used as reference non-steroidal anti-inflammatory drug ((NSAID)) in a dose of 3 mg//kg. The chosen parameters for cartilage integrity were glycosaminoglycan ((GAG)), hydroxyproline contents in cartilage and cartilage oligomeric matrix protein ((COMP)) in serum. The serum levels of tumour necrosis factor-alpha ((TNF-αα)), nitric oxide ((NO)) and the oxidative stress biomarkers such as blood glutathione ((GSH)) and plasma malondialdehyde ((MDA)) levels. Results: Induction of arthritis led to a reduction in GAG and hydroxyproline content of femoral cartilage and a corresponding rise in COMP in serum. Previous exposure to irradiation resulted in a milder reduction of GAG and hydroxyproline and a lesser rise in COMP. Treatment of arthritic irradiated and non-irradiated rats with 13%% AEP markedly prevented the breakdown of cartilage in a much more effective manner than diclofenac. Both AEP and diclofenac were equipotent in reducing the level of TNF-αα and were able to normalize NO and the oxidative stress biomarkers in non-irradiated and irradiated arthritic rats. Conclusion: The ability of propolis to protect cartilage degradation could therefore prove of value in the treatment of chronic arthritic diseases, offering an advantage over some NSAID, particularly those with a potential detrimental effect on cartilage integrity. [ABSTRACT FROM AUTHOR]

Purpose: The potential value of celecoxib was compared to a standard non-steroidal anti-inflammatory drug (NSAID), diclofenac in the adjuvant-induced arthritis (AIA) model in rats as a model of chronic inflammation under the influence of ionising radiation. Material and methods: Various inflammatory mediators and biochemical parameters were measured in the arthritic rats under the influence of ionising radiation. Results: Exposure of the animals to a radiation dose of 2 Gy before inoculation of the adjuvant led to a marked increase in the paw volume reaching ca. 70% more than that in non-irradiated ones as well as a significant increase in the levels of interleukin-6 (IL-6), interleukin-1β (IL-1β), tumour necrosis factor-α (TNF-α), prostaglandin E2 (PGE2) as an index of cyclooxygenase-2 (COX-2) activity, thromboxane B2 (TXB2) as an index of cyclooxygenase-1 (COX-1) activity and plasma level of malondialdehyde (MDA). The blood glutathione (GSH) level was not affected by the dose of irradiation used while superoxidedismutase (SOD) activity was reduced. Treatment with celecoxib in a dose of 5 mg/kg was effective in decreasing the elevated levels of IL-6, IL-1β, TNF-α, PGE2 whereas it lacked any effect on TXB2 level since it had hardly any effect on COX-1 enzyme. Both drugs at the selected dose levels showed no effect on level of MDA, GSH and SOD activity. Conclusion: Irradiation of animals caused a marked change in the inflammatory response in AIA model of inflammation. Both celecoxib and diclofenac were nearly equipotent in suppressing the inflammatory response in both normal and irradiated rats. Accordingly, since the inhibition of COX-1 by traditional NSAID is thought to have undesirable side-effects on proliferating tissues, it would seem preferable to use selective COX-2 inhibitors to limit such deleterious effect. [ABSTRACT FROM AUTHOR]

Solanum indicum ssp. distichum is used as a vegetable in some parts of Africa and claimed in folk medicine to guard against cardiovascular disorders. It was of interest to study the potential blood pressure lowering effects of a standardized extract of the fruit. An ethanolic extract of the fruit, standardized to contain > 0.15% chlorogenic acids, was tested orally in both normotensive rats and in those rendered hypertensive by twice daily intraperitoneal injection of NW-nitro-l-arginine methylester (l-NAME) for 1 week. The extract was either given at the same time asl-NAME or after the establishment of hypertension. The systolic blood pressure (SBP) was measured non-invasively using a tail cuff computer-aided monitoring device. Treatment of normotensive rats with the extract (30–300 mg/kg) for 4 weeks showed no hypotensive effect. Giving the extract (100 and 300 mg/kg) orally once daily during the 1 week hypertension induction period withl-NAME prevented the development of hypertension. Administration of the extract orally for 1 week after the establishment of hypertension tended to normalize the blood pressure. Pharmacological evidence for the antihypertensive activity of S. distichum is hereby reported for the first time. The extract showed good prophylactic as well as curative effect againstl-NAME-induced hypertension, whereby its content of chlorogenic acids may play a minor role. Other constituents may be responsible for the antihypertensive action. The findings support further development of the extract as a potential therapeutically useful antihypertensive agent. [ABSTRACT FROM AUTHOR]