Protective Effects of Nigella sativa Oil in Hyperoxia-Induced Lung Injury

Nigella sativa and its chemical constituents: pre-clinical and clinical evidence for their potential anti-SARS-CoV-2 effects

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused over 500 million reported cases of COVID-19 worldwide with relatively high morbidity and mortality. Although global vaccination drive has helped control the pandemic, the newer variant of the virus still holds the world in ransom. Several medicinal herbs with antiviral properties have been reported, and one such promising herb is Nigella sativa (NS). Recent molecular docking, pre-clinical, and clinical studies have shown that NS extracts may have the potential to prevent the entry of coronaviruses into the host cell as well as to treat and manage COVID-19 symptoms. Several active compounds from NS, such as nigelledine, α-hederin, dithymoquinone (DTQ), and thymoquinone (TQ), have been proposed as excellent ligands to target angiotensin-converting enzyme 2 (ACE2 receptors) and other targets on host cells as well as the spike protein (S protein) on SARS-CoV-2. By binding to these target proteins, these ligands could potentially prevent the binding between ACE2 and S protein. Though several articles have been published on the promising therapeutic role of NS and its constituents against SARS-CoV-2 infection, in this review, we consolidate the published information on NS and SARS-CoV-2, focusing on pre-clinical in silico studies as well as clinical trials reported between 2012 and 2023.

Etomidate attenuates hyperoxia-induced acute lung injury in mice by modulating the Nrf2/HO-1 signaling pathway

The present study aimed to investigate the protective effects of etomidate on hyperoxia-induced acute lung injury in mice, particularly on the nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway. Fifty specific pathogen-free mice were randomly divided into the blank control, model, high oxygen exposure + low etomidate dose (0.3 mg·kg^-1), a high oxygen exposure + moderate etomidate dose (3 mg·kg^-1), and a high oxygen exposure + high etomidate dose (10 mg·kg^-1) groups, with ten mice allotted per group. After 72 h, the mice were sacrificed and the lung tissues were harvested, and the wet-to-dry (W/D) ratio of the tissues was calculated. Hematoxylin-eosin staining was performed to observe the pathological changes in the lung tissues, and the lung injury score (LIS) was calculated. The mRNA and protein expression levels of Nrf2 and HO-1 were measured. The malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and catalase (CAT) levels were also measured, and interleukin (IL)-1β, IL-6, tumor necrosis factor alpha (TNF-α) and IL-10 concentrations in the bronchoalveolar lavage fluid were determined. At low and moderate doses, etomidate decreased pathological damage in the lung tissue, decreased the LIS and W/D ratio, upregulated Nrf2 and HO-1 mRNA and protein expression, decreased IL-1β, IL-6, and TNF-α concentrations, increased MPO activity and IL-10 levels, suppressed the production of the oxidation product MDA, and enhanced the activities of the antioxidant enzymes CAT and SOD. Within a certain dose range, etomidate enhanced antioxidant and anti-inflammatory effects in mice, thereby decreasing lung injury induced by the chronic inhalation of oxygen at high concentrations. Furthermore, the underlying mechanism may be associate with the upregulation of the Nrf2/HO-1 signaling pathway.

Protective Effect of Gemfibrozil on Hepatotoxicity Induced by Acetaminophen in Mice: the Importance of Oxidative Stress Suppression

Purpose: Gemfibrozil (GEM) apart from agonist activity at peroxisome proliferator-activated receptor-alpha (PPAR-α) has antioxidant and anti-inflammatory properties. Accordingly, the present study was designed to investigate the protective effect of GEM on acute liver toxicity induced by acetaminophen (APAP) in mice.

Methods: In this study, mice divided in seven groups include, control group, APAP group, GEM group, three APAP groups pretreated with GEM at the doses of 25, 50 and 100 mg/kg respectively and APAP group pretreated with N-Acetyl cysteine. GEM, NAC or vehicle were administered for 10 days. In last day, GEM and NAC were gavaged 1 h before and 1 h after APAP injection. Twenty four hours after APAP, mice were sacrificed. Serum parameters include alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver tissue markers including catalase enzyme activity, reactive oxygen species (ROS), malondialdehyde and reduced glutathione (GSH) levels determined and histopathological parameters measured.

Results: GEM led to significant decrease in serum ALT and AST activities and increase in catalase activity and hepatic GSH level and reduces malondialdehyde and ROS levels in the liver tissue. In confirmation, histopathological findings revealed that GEM decrease degeneration, vacuolation and necrosis of hepatocytes and infiltration of inflammatory cells.

Conclusion: Present data demonstrated that GEM has antioxidant properties and can protect the liver from APAP toxicity, just in the same pathway that toxicity occurs by toxic ROS and that GEM may be an alternative therapeutic agent to NAC in APAP toxicity.

Ethnobotanical survey of medicinal plants in northeastern of Algeria

BACKGROUND

In order to document medicinal uses of plants in the northeastern of Algeria, preserve traditional heritage and highlighted the risks of excessive human exploitation on flora and biodiversity of the region, an inventory of medicinal species existed in the traditional pharmacopoeia in Skikda region (north-east of Algeria) was made. The survey was carried out during the year (2015-2016), through face to face interviews, using pre-prepared questionnaire. The form contains: sociodemorgaphic profile of each respondent (sex, age, educational level and monthly income), local name of medicinal species used, uses, used parts and methods of preparations.

RESULTS

A total of 90 species belonging to 42 botanical families, were listed. The analysis of the obtained results showed that the frequency of use of medicinal plants is related to the age, sex, educational level and monthly income of our respondents. It was recorded that the majority of remedies are prepared in the form of a decoctate from the leaves of the different species, in order to treat a wide range of diseases especially those of the digestive tract.

CONCLUSION

Local population has a rich indigenous knowledge, but is always stays not adequately documented. It should be noted that some listed species are suffering from surexploitation which can subjects to the disappearance of the most vulnerable species. It will be urgent and essential to adopt a sustainable management strategy to avoid the degradation of biodiversity of the region.

Protective role of intratympanic nigella sativa oil against gentamicin induced hearing loss

OBJECTIVE

Aminoglycosides, used to combat with life-threatening infections, have a substantial risk of hearing loss. Nigella sativa is an annual herbaceous plant and used for treatment of many diseases for ages. We aimed to investigate the protective role of intratympanic nigella sativa oil against gentamicin induced hearing loss in an animal model.

METHODS AND MATERIALS

Twenty eight guinea pigs were randomly divided into four groups: i-control, ii- Intratympanic nigella sativa oil (IT-NSO), iii- Intraperitoneal gentamicin (IP-G) and iv- Intraperitoneal gentamicin and intratympanic nigella sativa oil (IP-G + IT-NSO). Preoperative and postoperative hearing thresholds were determined with auditory brainstem response with click and 8 kHz tone-burst stimuli. Histological analysis of the cochlea specimens were performed under light microscope. Semiquantitative grading of the histological findings was carried out and compared between the groups.

RESULTS

Highest posttreatment hearing thresholds were detected in IP-G group. Posttreatment mean hearing threshold of the IP-G group with click stimulus was significantly higher than the IP-G + IT-NSO group (p = 0.004). whereas the difference was not significant with 8 kHz tone-burst stimulus (p = 0.137). Both IP-G and IP-G + IT-NSO groups had significantly higher hearing thresholds compared to control and IT-NSO groups (p > 0.05). Histological examination of the control and IT-NSO groups demonstrated normal appearance of cochlear nerve, stria vascularis and organ of Corti. IP-G group showed the most severe histological alterations including hydropic and vacuolar degenerations, hair cell damage and deformation of the basilar mambrane. Histological evidence of damage was significantly reduced in IP-G + IT-NSO group compared to IP-G group.

CONCLUSION

Addition of intratympanic NSO to systemic gentamicin was demonstrated to have beneficial effects in hearing thresholds which was supported by histological findings.

Effect of Nigella sativa (black seeds) against methotrexate-induced nephrotoxicity in mice

Aim:

To evaluate the protective effect of Nigella sativa (NS) against nephrotoxicity of methotrexate (MTX) in mice.

Materials and Methods:

Four groups of Swiss albino male mice, eight in each group were used. The study was carried on between October 2014 and April 2015. Group 1 (control) were administered 0.3 ml distilled water orally daily for 21 days and injected with normal saline (0.25 ml) IP weekly. Group 2 (MTX group) were treated with MTX, 10 mg/kg IP weekly, while Group 3 were treated with 0.125 ml of NS oil by mouth daily and injected with normal saline (0.25 ml) IP weekly. Group 4 received 0.125 ml of NS oil by mouth daily and injected with 10 mg/kg MTX IP weekly. Oral treatments were administered using a special curved smooth tip nontraumatic metal needle and IP injections were given for 3 weeks at days 7, 14 and 21. Animals were sacrificed at day 23. Malondialdehyde (MDA) and glutathione (GSH) measurements were performed on kidney homogenate. Histopathology of the kidneys were prepared and examined.

Results:

MTX has resulted in a small elevation in MDA and reduction in GSH levels in kidney homogenate which was returned back to control values when NS and MTX were administered in combination. Statistical significance was achieved with elevation of GSH by MTX and NS compared to MTX alone. MTX caused histopathological changes suggesting nephrotoxicity in 6 animals out of 8, while no changes were found in all animals treated with MTX and NS.

Conclusion:

NS is protective against MTX-induced nephrotoxicity.

Biochanin A Ameliorates Arsenic-Induced Hepato- and Hematotoxicity in Rats

Biochanin A (BCA) is a natural organic compound of the phytoestrogenic isoflavone class that has antioxidant and metal chelator properties in the presence of transition metal ions, however, its efficacy in animal models is still obscure. Therefore, the objective of this study was to investigate the protective effects of BCA against arsenic-induced hepatic injury and hematotoxicity in rats. The results suggest that arsenic intoxicated rats showed significantly higher levels of plasma hepatic markers than normal control rats. Furthermore, an increase in lipid peroxidation with depletion of reduced glutathione (GSH) and activities of superoxide dismutase (SOD) and catalase (CAT) occurred in the livers of rats exposed to arsenic. Administration of BCA (20 mg/kg·bw/day) and selenium (3 mg/kg·bw/day) resulted in a significant reversal of hepatic and oxidative stress markers in arsenic-intoxicated rats. A low dose of BCA (10 mg/kg·bw/day) did not show any preventive effect, while a high dose of BCA (40 mg/kg·bw/day) partially prevented all hepatotoxicity events. These biochemical perturbations were supported by histopathological observations of the liver. Our results suggest that administration of BCA (20 mg/kg·bw/day) attenuated the arsenic hepatotoxicity, a property that could contribute to the therapeutic approaches for chronic liver diseases.

A review on therapeutic potential of Nigella sativa: A miracle herb

Nigella sativa (N. sativa) (Family Ranunculaceae) is a widely used medicinal plant throughout the world. It is very popular in various traditional systems of medicine like Unani and Tibb, Ayurveda and Siddha. Seeds and oil have a long history of folklore usage in various systems of medicines and food. The seeds of N. sativa have been widely used in the treatment of different diseases and ailments. In Islamic literature, it is considered as one of the greatest forms of healing medicine. It has been recommended for using on regular basis in Tibb-e-Nabwi (Prophetic Medicine). It has been widely used as antihypertensive, liver tonics, diuretics, digestive, anti-diarrheal, appetite stimulant, analgesics, anti-bacterial and in skin disorders. Extensive studies on N. sativa have been carried out by various researchers and a wide spectrum of its pharmacological actions have been explored which may include antidiabetic, anticancer, immunomodulator, analgesic, antimicrobial, anti-inflammatory, spasmolytic, bronchodilator, hepato-protective, renal protective, gastro-protective, antioxidant properties, etc. Due to its miraculous power of healing, N. sativa has got the place among the top ranked evidence based herbal medicines. This is also revealed that most of the therapeutic properties of this plant are due to the presence of thymoquinone which is major bioactive component of the essential oil. The present review is an effort to provide a detailed survey of the literature on scientific researches of pharmacognostical characteristics, chemical composition and pharmacological activities of the seeds of this plant.

Association between oxidative DNA damage and the expression of 8-oxoguanine DNA glycosylase 1 in lung epithelial cells of neonatal rats exposed to hyperoxia

Previous studies have demonstrated that oxidative stress‑induced lung injury is involved in the occurrence and developmental process of bronchopulmonary dysplasia (BPD). The present study assessed whether oxidative DNA damage occurs in the early stages of hyperoxia‑induced BPD in neonatal rats and evaluated the expression and localization of the DNA repair gene, 8‑oxoguanine DNA glycosylase 1 (OGG1), upon exposure to hyperoxia. Neonatal rats and primary cultured neonatal rat alveolar epithelial type II (AECII) cells were exposed to hyperoxia (90% O2) or normoxia (21% O2) and the expression levels of 8‑hydroxy‑2'‑deoxyguanosine (8‑OHdG) in the lung tissues and AECII cells were determined using a competitive enzyme‑linked immunosorbent assay. DNA strand breaks in the AECII cells were detected using a comet assay. The expression and localization of the OGG1 protein in the lung tissues and AECII cells were determined by immunofluorescence confocal microscopy and western blotting. The mRNA expression levels of OGG1 in the lung tissues and AECII cells were determined by reverse transcription polymerase chain reaction. The expression of 8‑OHdG was elevated in the hyperoxia‑exposed neonatal rat lung tissue and the AECII cells compared with the normoxic controls. The occurrence of DNA strand breaks in the AECII cells increased with increasing duration of hyperoxia exposure. The protein expression of OGG1 was significantly increased in the hyperoxia‑exposed lung tissues and AECII cells, with OGG1 preferentially localized to the cytoplasm. No concomitant increase in the mRNA expression of OGG1 was detected. These results revealed that oxidative DNA damage occurred in lung epithelial cells during early‑stage BPD, as confirmed by in vitro and in vivo hyperoxia exposure experiments, and the increased expression of OGG1 was associated with this process.

A study of antioxidant activity, enzymatic inhibition and in vitro toxicity of selected traditional Sudanese plants with anti-diabetic potential

Background

Diabetes mellitus is a chronic metabolic disease with life-threatening complications. Despite the enormous progress in conventional medicine and pharmaceutical industry, herbal-based medicines are still a common practice for the treatment of diabetes. This study evaluated ethanolic and aqueous extracts of selected Sudanese plants that are traditionally used to treat diabetes.

Methods

Extraction was carried out according to method described by Sukhdev et. al. and the extracts were tested for their glycogen phosphorylase inhibition, Brine shrimp lethality and antioxidant activity using (DPPH) radical scavenging activity and iron chelating activity. Extracts prepared from the leaves of Ambrosia maritima, fruits of Foeniculum vulgare and Ammi visnaga, exudates of Acacia Senegal, and seeds of Sesamum indicum and Nigella sativa.

Results

Nigella sativa ethanolic extract showed no toxicity on Brine shrimp Lethality Test, while its aqueous extract was toxic. All other extracts were highly toxic and ethanolic extracts of Foeniculum vulgare exhibited the highest toxicity. All plant extracts with exception of Acacia senegal revealed significant antioxidant activity in DPPH free radical scavenging assay.

Conclusions

These results highly agree with the ethnobotanical uses of these plants as antidiabetic. This study endorses further studies on plants investigated, to determine their potential for type 2 diabetes management. Moreover isolation and identification of active compounds are highly recommended.

Postnatal inflammation in the pathogenesis of bronchopulmonary dysplasia

Exposure to hyperoxia, invasive mechanical ventilation, and systemic/local sepsis are important antecedents of postnatal inflammation in the pathogenesis of bronchopulmonary dysplasia (BPD). This review will summarize information obtained from animal (baboon, lamb/sheep, rat and mouse) models that pertain to the specific inflammatory agents and signaling molecules that predispose a premature infant to BPD.

The effect of Nigella sativa Linn. seed on memory, attention and cognition in healthy human volunteers

BACKGROUND

Experimental evidences have demonstrated that Nigella sativa Linn. seed (NS) has positive modulation effects on aged rats with memory impairments, prevents against hippocampal pyramidal cell loss and enhances consolidation of recall capability of stored information and spatial memory in rats. NS has neuroprotective, nephroprotective, lung protective, cardioprotective, hepatoprotective activities as established by previous studies on animals. Several clinical trials with NS on human have also demonstrated beneficial effect.

AIM OF THE STUDY

The present study was designed to investigate the effects of NS on memory, attention and cognition in healthy elderly volunteers. Furthermore, safety profile of NS was assessed during the nine-week study period.

METHODS

Forty elderly volunteers were recruited and divided randomly into group A and group B--each consisting of 20 volunteers. The treatment procedure for group A was 500 mg NS capsule twice daily for nine weeks and Group B received placebo instead of NS in the similar manner. All the volunteers were assessed for neuropsychological state and safety profile twice before treatment and after nine weeks. The neuropsychological tests were logical memory test, digit span test, Rey-Osterrieth complex figure test, letter cancellation test, trail making test and stroop test. Safety profile was assessed by measuring biochemical markers of Cardiac (total cholesterol, triglycerides and high density lipoprotein cholesterol, very low density lipoprotein, low density lipoprotein cholesterol, creatine kinase-MB); Liver (aspartate aminotransferase, alanin aminotransferase, alkaline phosphatase, total protein, albumin, bilirubin) and Kidney (creatinine and blood urea nitrogen) through using commercial kits.

RESULTS

There was significant difference (p<0.05) in the score of logical memory test-I and II, total score of digit span, 30 min delayed-recall, percent score in Rey-Osterrieth complex figure test, time taken to complete letter cancellation test, time taken in trail making test-A and test-B, score in part C of stroop test due to ingestion of NS for nine weeks. There were not statistically significant changes (p>0.05) in any of the biochemical markers of cardiac, liver, kidney function during this nine-week study period.

CONCLUSIONS

The current study demonstrates the role of NS in enhancing memory, attention and cognition. Therefore, whether NS could be considered as potential food supplement for preventing or slow progressing of Alzheimer disease needs further investigations. However, study with Alzheimer's patients with large population size for longer period of time is recommended before using NS daily and extensive phytochemical investigations are recommended for novel drug discovery from NS for treating cognitive disorders.

A Spotlight on Chemical Constituents and Pharmacological Activities ofNigella glanduliferaFreyn et Sint Seeds

Plants belonging to the Ranunculaceae family, and particularly their seeds, have been a hot research topic in numerous pharmacognosy laboratories.Nigella glanduliferaFreyn et Sint (NG) is one of the promising, but relatively insufficiently studied, plants from this family. In this review, we summarize the recently isolated chemical constituents from the seeds of this plant including alkaloids, flavonol glycosides, isobenzofuranone derivatives, saponins, terpenes, terpenoids, and fatty acids. We put also a spotlight on the recently studied therapeutic potentials of such amazing herb seeds as antidiabetes, melanogenesis inhibition, anticancer, anti-inflammatory, antithrombosis, and antiplatelet aggregation effects. Herein, we illustrate certain properties and potentials via selected examples, and thus we suggest more studies to confirm the therapeutic hypotheses, find out new compounds, and eventually to discover novel properties.