Development and Validation of Analytical Method for Simultaneous Estimation of Active Constituents in a Polyherbal Ointment by Gas Chromatography.

Background: The simultaneous, quantitative determination of all active ingredients present in the analgesic formulation (Dazzle ointment) requires an ideal and novel method by which these phytoconstituents can be separated with the highest resolution without any interference from one another. Objective: The present work was conducted to develop and validate a quantitative method for the simultaneous estimation of all five phytoconstituents present in a polyherbal analgesic ointment by GC. Methods: α-Pinene, 1,8-cineole, camphor, menthol, and methyl salicylate present in the ingredients of the ointment were analyzed and quantified by GC using a crosslinked 5% phenyl polydimethylsiloxane capillary column, nitrogen as a carrier gas, and a flame-ionization detector. Aniline was used as the internal standard. Method validation was also performed in order to demonstrate its selectivity, linearity, accuracy, precision, LOD, LOQ, and robustness. Results: The calibration curves of all five marker compounds showed good linear correlation coefficients (r² >0.998) within the tested ranges. The precision of the method was tested by carrying out intra- and interday analyses of the same sample. RSD values were observed to be <1.00%. The accuracy of the method, determined by performing recovery studies, was found to be between 99.25 and 101.39%. The developed method was also demonstrated to be robust (RSD <1.29%) by making small but deliberate variations in method parameters. Conclusions: The developed GC method is simple, precise, and accurate, it and can be used for the rapid quality control testing of the polyherbal formulation. Highlights: The developed GC method will assist in the standardization of polyherbal analgesic formulation consists of α-pinene, 1,8-cineole, camphor, menthol, and methyl salicylate as active constituents.

Leptin engages a hypothalamic neurocircuitry to permit survival in the absence of insulin.

The dogma that life without insulin is incompatible has recently been challenged by results showing the viability of insulin-deficient rodents undergoing leptin monotherapy. Yet, the mechanisms underlying these actions of leptin are unknown. Here, the metabolic outcomes of intracerebroventricular (i.c.v.) administration of leptin in mice devoid of insulin and lacking or re-expressing leptin receptors (LEPRs) only in selected neuronal groups were assessed. Our results demonstrate that concomitant re-expression of LEPRs only in hypothalamic γ-aminobutyric acid (GABA) and pro-opiomelanocortin (POMC) neurons is sufficient to fully mediate the lifesaving and antidiabetic actions of leptin in insulin deficiency. Our analyses indicate that enhanced glucose uptake by brown adipose tissue and soleus muscle, as well as improved hepatic metabolism, underlies these effects of leptin. Collectively, our data elucidate a hypothalamic-dependent pathway enabling life without insulin and hence pave the way for developing better treatments for diseases of insulin deficiency.