Sub-chronic oral toxicity evaluation of herbo-metallic formulation Arshakuthar rasa in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Arshakuthar rasa (AR) is a mercury based Ayurvedic herbo-metallic formulation. The concerns are being raised about the probable toxicity of mercury after prolonged use of AR. Hence, there is need for a long-term repeated in vivo toxicity study. The study will provide data with scientific evidence to enable safe use of the drug. Moreover, lack of toxicity study with AR incited us to perform sub-chronic study on rats. AIM OF THE STUDY: The aim of the study is to generate data by performing a sub-chronic study to assess the toxicity of AR after its prolonged oral intake. MATERIALS AND METHODS: The female and male rats were administered with 30 (low), 300 (medium) and 600 mg/kg BW/day (high) dose of AR for 90 consecutive days. The body weight, feed consumption and water intake were monitored weekly. On 91st day, blood was collected from retro-orbital plexus of rats and then sacrificed to harvest the vital organs for biochemical, haematological, histopathological, genotoxicity along with the expression study of oxidative stress related genes and the biodistribution of elements in the blood. RESULTS: Significant alterations in serum biochemical parameters were observed at the medium and high doses. The histopathological changes were in corroboration with biochemical changes at high dose in liver. There was no detectable level of mercury in blood, less to moderate biochemical changes, no haematological changes, moderate regulation of stress-related genes, and low genotoxicity. These results indicated that AR can be considered as moderately toxic above 600 mg/kg BW and mildly toxic at 300 mg/kg BW. CONCLUSIONS: It may be interpreted that AR may not induce grave toxic response in human after long-duration of oral administration at therapeutic doses.

Dehydrozingerone ameliorates Lipopolysaccharide induced acute respiratory distress syndrome by inhibiting cytokine storm, oxidative stress via modulating the MAPK/NF-κB pathway.

BACKGROUND: Inflammation-mediated lung injury is a major cause of health problems in many countries and has been the leading cause of morbidity/mortality in intensive care units. In the current COVID-19 pandemic, the majority of the patients experienced serious pneumonia resulting from inflammation (Acute respiratory distress syndrome/ARDS). Pathogenic infections cause cytokine release syndrome (CRS) by hyperactivation of immune cells, which in turn release excessive cytokines causing ARDS. Currently, there are no standard therapies for viral, bacterial or pathogen-mediated CRS. PURPOSE: This study aimed to investigate and validate the protective effects of Dehydrozingerone (DHZ) against LPS induced lung cell injury by in-vitro and in-vivo models and to gain insights into the molecular mechanisms that mediate these therapeutic effects. METHODS: The therapeutic activity of DHZ was determined in in-vitro models by pre-treating the cells with DHZ and exposed to LPS to stimulate the inflammatory cascade of events. We analysed the effect of DHZ on LPS induced inflammatory cytokines, chemokines and cell damage markers expression/levels using various cell lines. We performed gene expression, ELISA, and western blot analysis to elucidate the effect of DHZ on inflammation and its modulation of MAPK and NF-κB pathways. Further, the prophylactic and therapeutic effect of DHZ was evaluated against the LPS induced ARDS model in rats. RESULTS: DHZ significantly (p < 0.01) attenuated the LPS induced ROS, inflammatory cytokine, chemokine gene expression and protein release in macrophages. Similarly, DHZ treatment protected the lung epithelial and endothelial cells by mitigating the LPS induced inflammatory events in a dose-dependent manner. In vivo analysis showed that DHZ treatment significantly (p < 0.001) mitigated the LPS induced ARDS pathophysiology of increase in the inflammatory cells in BALF, inflammatory cytokine and chemokines in lung tissues. LPS stimulated neutrophil-mediated events, apoptosis, alveolar wall thickening and alveolar inflammation were profoundly reduced by DHZ treatment in a rat model. CONCLUSION: This study demonstrates for the first time that DHZ has the potential to ameliorate LPS induced ARDS by inhibiting cytokine storm and oxidative through modulating the MAPK and NF-κB pathways. This data provides pre-clinical support to develop DHZ as a potential therapeutic agent against ARDS.

Supplementation of oat (Avena sativa L.) extract abates alcohol-induced acute liver injury in a mouse model.

Dietary supplementation of oats has been associated with reduced risk of cardiovascular disease, diabetes, and gastrointestinal disorders. The role of oat extract as prophylactic in treating acute liver injury is not thoroughly established. We, therefore, hypothesized that oat extract would exert protective effect against alcohol-induced acute liver injury in a mouse model. To test this hypothesis, male C57BL/6 mice were pretreated with phenolic-enriched ethyl acetate (EA) fraction of oats (prepared by fractionating aqueous ethanolic extract with solvents of increasing polarity) at dosages of 125 and 250 mg kg-1 d-1 for 12 consecutive days. Acute liver injury was induced by administering 5 doses of 50% ethanol intragastrically (10 g/kg body weight) to mice at an interval of 12 hours. The alcohol-induced liver injury was evaluated by measuring serum levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, antioxidant parameters, mitochondrial function, and histology of liver tissue. Our results demonstrated that pretreatment with EA fraction at 250 mg kg-1 d-1 significantly (P < .001 for aspartate aminotransferase, alanine aminotransferase, and thiobarbituric acid-reactive species and P < .01 for lactate dehydrogenase and nitrites) reduced the levels of liver injury markers and significantly (P < .001 for glutathione reductase and glutathione S-transferase; P < .01 for catalase, superoxide dismustase, and vitamin C; P < .05 for reduced glutathione and NAD(P)H quinone dehydrogenase 1) increased the levels of antioxidant defenses. Furthermore, EA-pretreated mice showed mechanistic inhibition of nuclear factor κB signaling pathway through decreased phosphorylation and degradation of IκBα. We conclude that phenolic-enriched EA fraction of oats has immense potential to serve as dietary intervention against alcohol-induced liver damage.