ABSTRACT
Introduction: SIRTs (Sirtuins) are class III histone deacetylase enzymes that use NAD+ as a co-substrate for their enzymaticactivities. In mammals, there are seven sirtuin proteins (SIRT1–SIRT7) among which SIRT4, SIRT3 and SIRT5 are mitochondrialsirtuins that regulate enzymes and other mitochondrial proteins to coordinate oxidative production of ATP with the availability ofenergy in the diet. SIRT4 is known to have tumor suppression activity in many human cancers. However, the role of SIRT4 inoral squamous cell carcinoma is not known. It is present at higher levels under nutrient-rich conditions, and inhibits glutaminecatabolism through ADP-ribosylation and hence repression of glutamate dehydrogenase (GDH) activity, a rate-limiting enzymein glutamine catabolism. Due to higher requirement of energy and bio-molecules for proliferation, cancer cell often resort tovarious metabolic pathways that are otherwise uncommon in normal cells. One of such mechanism is switching to Glutaminemetabolism. SIRT4 acts as a tumor suppressor by repressing glutamine utilisation by cells.Purpose: Study the role of SIRT4 in oral squamous cell carcinoma and evaluate its tumor suppressor role.Method: Here we studied expression of SIRT4 in oral cancer tissues by immuohistochemistry and compared it with that ofnormal tissue.Results: SIRT 4 was seen to significantly down regulated in oral squamous carcinoma.Conclusion: The present study suggests SIRT4 as a marker of tumor aggressiveness and as a therapeutic target for OSCC.
ABSTRACT
Objective: To evaluate the anti-inflammatory and antidiabetic property of Bauhinia vahlii (stem bark) with preliminary phytochemical profile of the extracts. Methods: The dried whole plant material (1400 g) was packed in soxhlet apparatus and extracted successively with Pet. Ether (PE) to defat the drug, petroleum ether was removed from the powdered defatted drug which was then extracted with benzene (BE), chloroform(CE) and 95% of Ethanol (EE) as increasing polarity and all extracts screened for anti-inflammatory and antidiabetic activity using carrageenan induced paw edema and streptozotacin induced diabetic respectively. The toxicity and phytochemical screening were done using standard procedure. Result: The preliminary phytochemical tests revealed the presence of alkaloids, flavonoids, phytosterol, phenolic compounds, and glycoside. While carbohydrates, protein, gums and amino acids were absent. The acute toxicity study of various extracts of Bauhinia vahlii was conducted and dose of 353 mg/kg is fixed for anti-inflammatory and antidiabetic perperty. The pet ether, chloroform and ethanolic extract ofBauhinia vahlii significantly decreased the paw edema induced by carrageenin in rats at a dose of 353 mg/kg comparable to standard ibuprofen (100 mg/kg). Similarly in case of antidiabetic property, the ethanolic and chloroform extract of Bauhinia vahlii at a dose level 353 mg/kg, showed significant reduction in blood sugar level from 2 to 24 h in progressive manner comparable to standard glibenclamide (5mg/kg).