Effects of crocin on reperfusion-induced oxidative/nitrative injury to cerebral microvessels after global cerebral ischemia

Effects of intraperitoneal and intracerebroventricular injection of crocin on acute corneal pain in rats

In this study, the effects of intraperitoneal (i.p.) and intracerebroventricular (i.c.v.) injection of crocin in separate and combined treatments with i.p. injections of morphine (an opioid receptor agonist) and naloxone (an opioid receptor antagonist) were investigated on acute corneal pain in rats. Acute corneal pain was induced by local application of a drop of 5 M NaCl solution on the corneal surface. The number of eye wipes was taken as a pain response, and counted during the first 30 s. Crocin injected i.p. and i.c.v. and morphine injected i.p. significantly (p < 0.05) decreased the number of eye wipes. Morphine (i.p.)-induced antinociception was significantly (p < 0.05) increased by the systemically and centrally injected crocin. The antinociceptive effects induced by i.p. and i.c.v. injections of crocin were not reversed by i.p. injection of naloxone. These findings indicated that both crocin and morphine attenuated hypertonic saline-induced corneal pain. The opioid receptors may not be involved in the analgesic mechanism of crocin.

Saffron suppresses oxidative stress in DMBA-induced skin carcinoma: A histopathological study

Cancer chemoprevention is the use of natural, synthetic or biological substances to reverse or prevent the development of cancer. Saffron is a naturally derived plant product that acts as an antispasmodic, diaphoretic, carminative, emmenagogic and sedative. Our aim in this study was to investigate the chemopreventive effect of aqueous saffron on chemically induced skin carcinogenesis using a histopathological approach. Mice were divided into five groups: carcinogen control (CC), normal control (NC) and saffron-treated Groups A, B and C. Groups A, B, C and CC mice received three topical applications of 7,12 dimethylbenz[a]anthracene (DMBA) followed by croton oil on shaven dorsal skin for 8 weeks. NC mice received topical skin applications of the vehicle, acetone, only. Saffron infusion was fed orally to three groups of mice either before (Group A) or after (Group C) or both before and after (Group B) DMBA applications. The activities of antioxidant enzymes glutathione-S transferase (GST), glutathione peroxidase (GPx), catalase (CAT) and superoxide dismutase (SOD) in liver tissue samples taken at 0, 6, 10 and 12 weeks from all groups were assessed. Standard histological examination of skin demonstrated a beneficial action of saffron in mice where saffron treatments were given both before and after the induction of skin carcinogenesis. Saffron ingestion inhibited the formation of skin papillomas in animals and simultaneously reduced their size. In conclusion, saffron inhibits DMBA-induced skin carcinoma in mice when treated early. This may be due, at least in part, to the induction of cellular defense systems.

The effect of saffron consumption on biochemical and histopathological heart indices of rats with myocardial infarction

This study was designed to assess the effects of saffron (Crocus sativus) on rats' heart with isoproterenol-induced myocardial injury. Animals were divided randomly into four groups: vehicle-control group (CTL); ISO group, administrated with Isoproterenol 85 mg/kg s.c.; saffron group; and finally combined Saffron + ISO group. Basal and final serum levels of heart troponin I, heart tissue antioxidants and histopathological indices were assessed in all groups. Isoproterenol administration significantly increased serum level of troponin I when compared to control group (3.46 +/- 0.77 vs. 0.53 +/- 0.35 ml in ng/ml, P < 0.001) and reduced significantly the glutathione peroxidase activity of heart muscle (1.63 +/- 0.21 vs. 4.01 +/- 0.64 nmol/mg protein, P < 0.05). The grade of heart muscle damages was severe in more than 70% of ISO group animals. Saffron + ISO group showed remarkably decreased intensity of tissue destruction and significantly decreased serum levels of heart troponin I, when compared to ISO group (1.25 +/- 0.23 vs. 3.46 +/- 0.77 ng/ml, P < 0.05). The level of glutathione peroxidase activity in Saffron + ISO animals did not have significant decline compared to saffron alone. These results suggest the protective role of saffron on ischemic hearts by biochemical and histopathological findings.

Preventive effect of crocin of Crocus sativus on hemodynamic, biochemical, histopathological and ultrastuctural alterations in isoproterenol-induced cardiotoxicity in rats

We investigated the effects of crocin, a pharmacologically active constituent of Crocus sativus L., in isoproterenol (ISO)-induced cardiotoxicity with reference to hemodynamic, antioxidant, histopathological and ultrastructural parameters. Rats were administered crocin (5, 10 and 20mg/kg/day) or vehicle orally for 21 days along with ISO (85mg/kg, subcutaneously, at 24h interval) on 20th and 21st day. On 22nd day ISO-control rats showed cardiac dysfunction as indicated by lowering of systolic, diastolic and mean arterial blood pressures. In addition, a significant decrease in maximum positive and negative rate of developed left ventricular pressure (+/-LVdp/dt(max)) and an increase in left ventricular end-diastolic pressure (LVEDP) were observed. Furthermore, a marked reduction in the activities of myocardial creatine kinase-MB (CK-MB) isoenzyme, lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH) levels along with an increase in content of malondialdehyde (MDA) were observed. Myocardial necrosis, edema and inflammation were evident from the light microscopic and ultrastructural changes. Crocin at the dose of 20mg/kg/day significantly modulated hemodynamic and antioxidant derangements. The preventive role of crocin on ISO-induced MI was reconfirmed by histopathological and ultrastructural examinations. The effect at the dose of 20mg/kg/day of crocin was more pronounced than that of other two doses (5 and 10mg/kg/day). The results suggest that crocin may have cardioprotective effect in ISO-induced cardiac toxicity through modulation of oxidative stress in such a way that maintains the redox status of the cell.

Improving the effect of incubation and oxidative stress on thawed spermatozoa from red deer by using different antioxidant treatments

Antioxidants could improve sperm media, extending the viability of spermatozoa and protecting their DNA. The protective ability of lipoic acid, melatonin, Trolox and crocin was tested on red deer spermatozoa incubated at 37°C. Cryopreserved spermatozoa were thawed and incubated with 1 mM or 0.1 mM of each antioxidant, with or without oxidative stress (100 μM Fe2+). Motility (CASA), viability, mitochondrial membrane potential and acrosomal status were assessed. Lipoperoxidation (malondialdehyde production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were checked at 4 h. Incubation alone increased ROS and decreased motility. Oxidative stress intensified these effects, increasing lipoperoxidation and DNA damage. Lipoic acid had little protective effect, whereas 1 mM melatonin showed limited protection. Trolox lowered ROS and lipoperoxidation both in oxidised and non-oxidised samples. In oxidised samples, Trolox prevented DNA and acrosomal damage, and ameliorated motility. Crocin at 1 mM showed similar results to Trolox, but noticeably stimulated motility and had no effect on lipoperoxidation. In a second experiment, a broader range of crocin and melatonin concentrations were tested, confirming the effects of crocin (positive effects noticeable at 0.5–0.75 mM), but showing an increase in lipoperoxidation at 2 mM. Melatonin was increasingly effective at 2.5 and 5 mM (ROS, lipoperoxidation and DNA status). Crocin seems a promising new antioxidant, but its particular effects on sperm physiology must be further studied, especially the consequences of motility stimulation and confirming its effect on lipoperoxidation. Melatonin might be useful at relatively high concentrations, compared to Trolox.

Mmp-9, a potential target for cerebral ischemic treatment

Matrix metalloproteinase-9 (MMP-9) which is a member of matrix metalloproteinases family that normally remodel the extracellular matrix, has been shown to play an important role in both animal models of cerebral ischemia and human stroke. The expression of MMP-9 is elevated after cerebral ischemia which is involved in accelerating matrix degradation, disrupting the blood-brain barrier, increasing the infarct size and relating to hemorrhagic transformation. Recently, many drugs, such as tetracycline derivatives, cyclooxygenase inhibitors, ACEI inhibitors and AT1 receptor blockers, etc., have been found to attenuate the elevated expression levels of MMP-9 after ischemia and to reduce the damage of cerebral ischemic. This article reviews the physiological features of MMP-9 and its important role in the genesis, propagation, and therapeutics of cerebral ischemic diseases.