A brain-sparing diphtheria toxin for chemical genetic ablation of peripheral cell lineages.

Conditional expression of diphtheria toxin receptor (DTR) is widely used for tissue-specific ablation of cells. However, diphtheria toxin (DT) crosses the blood-brain barrier, which limits its utility for ablating peripheral cells using Cre drivers that are also expressed in the central nervous system (CNS). Here we report the development of a brain-sparing DT, termed BRAINSPAReDT, for tissue-specific genetic ablation of cells outside the CNS. We prevent blood-brain barrier passage of DT through PEGylation, which polarizes the molecule and increases its size. We validate BRAINSPAReDT with regional genetic sympathectomy: BRAINSPAReDT ablates peripheral but not central catecholaminergic neurons, thus avoiding the Parkinson-like phenotype associated with full dopaminergic depletion. Regional sympathectomy compromises adipose tissue thermogenesis, and renders mice susceptible to obesity. We provide a proof of principle that BRAINSPAReDT can be used for Cre/DTR tissue-specific ablation outside the brain using CNS drivers, while consolidating the link between adiposity and the sympathetic nervous system

Determination of magnesium hydroxide in complex preparations with acetylsalicylic acid by reverse alkalimetric titration

The purpose of the study is to develop a methodology for the quantitative determination of magnesium hydroxide in a complex preparation by the method of alkalimetry.Цель исследования - разработка методики количественного определения магния гидроксида в комплексном препарате методом алкалиметрии

Brain-Sparing Sympathofacilitators Mitigate Obesity without Adverse Cardiovascular Effects.

Anti-obesity drugs in the amphetamine (AMPH) class act in the brain to reduce appetite and increase locomotion. They are also characterized by adverse cardiovascular effects with origin that, despite absence of any in vivo evidence, is attributed to a direct sympathomimetic action in the heart. Here, we show that the cardiac side effects of AMPH originate from the brain and can be circumvented by PEGylation (PEGyAMPH) to exclude its central action. PEGyAMPH does not enter the brain and facilitates SNS activity via theβ2-adrenoceptor, protecting mice against obesity by increasing lipolysis and thermogenesis, coupled to higher heat dissipation, which acts as an energy sink to increase energy expenditure without altering food intake or locomotor activity. Thus, we provide proof-of-principle for a novel class of exclusively peripheral anti-obesity sympathofacilitators that are devoid of any cardiovascular and brain-related side effects

Method Development for Quantitative Determination of Diosgenin from the Seeds of Fenugreek, <i>Trigonella foenum-graecum</i> L.

Introduction. Modern pharmacognostic research is aimed at searching for plant biologically active individual compounds (RBAIS) isolated from plant extracts.Aim. Study of the content of the steroid sapogenin diosgenin in fenugreek seeds in plant extracts by HPLC-UV method.Materials and methods. The object of study was raw materials-fenugreek seeds produced as medicinal plant raw materials by LLC «Sage» (Irkutsk). Series of extraction and chromatographic separation by HPLC-UV method were performed.Results and discussion. In this work, the method of diosgenin extraction was successfully optimized (after acid hydrolysis of dioscin with a 5 % aqueous solution of hydrochloric acid when heated for at least 4 hours in a sand bath at a power of 150 W) from raw fenugreek seeds using a 50 % aqueous solution of isopropanol, h.h. A simplified technique for chromatographic separation of diosgenin from fenugreek seed extracts using an isocratic mode of 99.9 % acetonitrile elution (h.h.) was proposed.Conclusion. The average content of diosgenin (after acid hydrolysis of dioscin) in fenugreek seeds, taking into account the humidity of raw materials, is (M ± σ) 5,3 ± 0,05 mg/g (95 % CI: 5,1-5,4 mg/g; n = 6)

Validation of the HPLC-UV Method for Quantitative Determination of Steroid Sapogenin Diosgenin from Hay Fenugreek Seeds, Trigonella Foenum-graecum L.

Introduction. Modern pharmacognostic research is aimed at searching for plant biologically active individual compounds (hereinafter referred to as RBAIS) isolated from plant extracts.Aim. Validation of HPLC-UV quantitative determination of sapogenin diosgenin in plant extracts from fenugreek seeds.Materials and methods. The object of study was raw materials-fenugreek seeds produced as medicinal plant raw materials by LLC «Sage» (Irkutsk). Validation of the method was carried out according to the parameters: specificity, linearity, correctness, precision in accordance with the requirements of SP XIV. One series of medicinal plant raw materials was used for the analysis, such as serial number – 010117, release date – 15 february 2017.Results and discussion. Validation characteristics were determined and their compliance with the necessary acceptance criteria was experimentally confirmed.Conclusion. It is established that the developed method of identification and quantitative determination of diosgenin in fenugreek seed extracts by HPLC-UV is correct, precise, specific and linear in the analytical field

Corrigendum: A brain-sparing diphtheria toxin for chemical genetic ablation of peripheral cell lineages.

The financial support for this Article was not fully acknowledged. The Acknowledgements should have included the following: [***Human Frontiers Science Program (HFSP) funds the labs of A.I.D. and P.C. ***]

Sympathetic neuro-adipose connections mediate leptin-driven lipolysis

Leptin is a hormone produced by the adipose tissue that acts in the brain, stimulating white fat breakdown. We find that the lipolytic effect of leptin is mediated through the action of sympathetic nerve fibers that innervate the adipose tissue. Using intravital two-photon microscopy, we observe that sympathetic nerve fibers establish neuro-adipose junctions, directly “enveloping” adipocytes. Local optogenetic stimulation of sympathetic inputs induces a local lipolytic response and depletion of white adipose mass. Conversely, genetic ablation of sympathetic inputs onto fat pads blocks leptin-stimulated phosphorylation of hormone-sensitive lipase and consequent lipolysis, as do knockouts of dopamine β-hydroxylase, an enzyme required for catecholamine synthesis. Thus, neuro-adipose junctions are necessary and sufficient for the induction of lipolysis in white adipose tissue and are an efferent effector of leptin action. Direct activation of sympathetic inputs to adipose tissues may represent an alternative approach to induce fat loss, circumventing central leptin resistance. </p

Sympathetic neuro-adipose connections mediate leptin-driven lipolysis

Leptin is a hormone produced by the adipose tissue that acts in the brain, stimulating white fat breakdown. We find that the lipolytic effect of leptin is mediated through the action of sympathetic nerve fibers that innervate the adipose tissue. Using intravital two-photon microscopy, we observe that sympathetic nerve fibers establish neuro-adipose junctions, directly “enveloping” adipocytes. Local optogenetic stimulation of sympathetic inputs induces a local lipolytic response and depletion of white adipose mass. Conversely, genetic ablation of sympathetic inputs onto fat pads blocks leptin-stimulated phosphorylation of hormone-sensitive lipase and consequent lipolysis, as do knockouts of dopamine β-hydroxylase, an enzyme required for catecholamine synthesis. Thus, neuro-adipose junctions are necessary and sufficient for the induction of lipolysis in white adipose tissue and are an efferent effector of leptin action. Direct activation of sympathetic inputs to adipose tissues may represent an alternative approach to induce fat loss, circumventing central leptin resistance. </p