Nigella sativa (NS) has wide-ranging healing properties, neuroprotective and antioxidant effects. Aging process is commonly associated with a decline in the chemical senses including smell. To detect a possible improvement effect of NS on the aging of the olfactory system we used 15 female albino rats that equally divided into three groups: group I (control adult), group II (control aged), group III (treated aged) received 40 mg/kg/day NS orally for two months. Specimens from the olfactory epithelium (OE), main olfactory bulb (MOB) and piriform cortex (PC) were processed for light and electron microscopy. Aging in OE revealed reduction in thickness, vacuolations, an increase in PAS reaction and lipofuscin autofluorescence. Aged MOB and PC exhibited a reduction in basophilia and accumulation of neurofibrillary tangles (NFTs) in mitral and pyramidal cells respectively. NS treatment improved the structure and the thickness of the OE and reduced the lipofuscin autofluorescence. It also attenuated the reduction in cytoplasmic basophilia and the accumulation of lipofuscin pigment and the NFTs in both mitral and pyramidal cells and the lipofuscin autofluorescence. These observations indicate that use of NS, could be of value in improving the structural changes of the peripheral and central main olfactory organs, which occurred in association with aging.

Chronic liver diseases and cirrhosis are now being recognized as an important cause of morbidity and mortality worldwide. Established cirrhosis has a 10-year mortality of 34-66%. Hepatorenal syndrome and spontaneous bacterial peritonitis are important cause of mortality in cirrhosis. Patients with liver cirrhosis are mostly asymptomatic until decompensation occurs, so it is very difficult to assess the real prevalence and incidence of cirrhosis in the general population. In the liver miR-122 accounts for approximately 70% of all miRs, whereas other organs express much lower amounts of this miR. miR-122 regulates many genes in the liver that control the cell cycle, differentiation, proliferation and apoptosis. In contrast loss of miR-122 in the liver leads to hepatic differentiation with malignant phenotype. The aim of the study: was to evaluate miR-122 as a prognostic marker in patients with liver cirrhosis. Methods: The study included 100 patients with liver cirrhosis All were subjected to clinical evaluation, abdominal ultrasonography, a group of laboratory investigations and serum miR-122 level by real time PCR Results: Serum miR-122 level among the studied groups showed significant statistical difference between group I "compensated" and both groups II "ascites" and III "SBP" (P0.001), while there was high statistical significanct difference between group I "compensated" and group IV ''HRS'' (P0.001). strong negative correlation between serum miR-122 level and MELD score (p=0.001), and very strong negative correlation between serum miR-122 level and Child score (p 0.001). Conclusion: Lower serum miR-122 levels are associated with ascites, spontaneous bacterial peritonitis and hepatorenal syndrome. Therefore, serum miR-122 could be considered as a new potential parameter for liver function and a prognostic parameter in patients with liver cirrhosis.