Tramadol, a frequently used pain reliever drug, present neurotoxic effects associated to cognitive dysfunction. Moreover, crocin has been reported to have neuroprotective effects. The aim of this study was to assess crocin’s capacity to protect learning, and memory abilities on tramadol-treated rats. A total of 35 rats were divided into five groups: Control, Saline, tramadol (50 mg/kg), tramadol + crocin(30 mg/kg), crocin groups and treated orally for 28 consecutive days. Morris water maze (MWM) and passive avoidance (PA) tests were done, followed by dissection of the rat’s brains for toluidine blue and TUNEL staining. In MWM test, tramadol group spent lower time and traveled shorter distance in the target quadrant (Q1) (P < 0.05). On the other side, the traveled distance in tramadol-crocin group was higher than tramadol (P < 0.05). In PA test, both the delay for entering the dark, and the total time spent in the light compartment decreased in tramadol comparing to the control group (P < 0.05), while it increased in tramadol-crocin compared with the tramadol group (P < 0.05). In tramadol-treated animals, the dark neurons (DNs) and apoptotic cells in CA1, CA3 and DG increased (P < 0.05), while concurrent intake of crocin decreased the number of DNs and apoptotic cells in these areas (P < 0.05). Crocin was able to improve learning and memory of tramadol-treated rats and also decreased DNs and apoptotic cells in the hippocampus. Considering these results, the potential capacity of crocin for decreasing side effects of tramadol on the nervous system is suggested.

Background: Type-one diabetes (T1D), a chronic autoimmune disease with marked inflammatory responses, is associated with infertility complications and implications. Based on the anti-diabetic, antioxidant, and anti-hyperlipidemic potential of Portulaca oleracea (PO), this study aimed to evaluate the protective effect of this plant extract on streptozotocin-induced type-I-diabetes-associated reproductive system dysfunction and inflammation. Methods: Male rats were randomly divided into four experimental groups: control, diabetic, and treatment/s (PO extract at 100 or 300 mg/kg/daily). Then food and water consumption, body, testis and epididymis weights, histopathological evaluation, seminiferous tubules diameter, sperm count and motility, glucose levels, sex hormones, and inflammatory and oxidative stress markers were evaluated. Results: Our results showed that streptozotocin-induced diabetes significantly increased food and water consumption; increased glucose, MDA, TGF-β1, and TNF-α levels; and decreased the seminiferous tubules diameter, sperm count and motility, levels of LH, testosterone, total thiol, VEGF, and SOD activity. Interestingly, PO extract (phytochemically characterized by using liquid chromatography–mass spectrometry to detect bioactive molecules) significantly ameliorated these parameters and histopathological indexes’ damage in rats. Conclusion. Even if more preclinical assessments are needed to better characterize the mechanism/s of action, the results of this study will pave the way for the rational use of PO on diabetic-associated clinical complications and implications.