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The plasma membrane glucose transporter-2 (GLUT2) monitors brain cell uptake of the critical nutrient glucose, and functions within astrocytes of as-yet-unknown location to control glucose counter-regulation. Hypothalamic astrocyte-neuron metabolic coupling provides vital cues to the neural glucostatic network. Current research utilized an established hypothalamic primary astrocyte culture model along with gene knockdown tools to investigate whether GLUT2 imposes sex-specific regulation of glucose/energy sensor function and glycogen metabolism in this cell population. Data show that GLUT2 stimulates or inhibits glucokinase (GCK) expression in glucose-supplied versus -deprived male astrocytes, but does not control this protein in female. Astrocyte 5'-AMP-activated protein kinaseα1/2 (AMPK) protein is augmented by GLUT2 in each sex, but phosphoAMPKα1/2 is coincidently up- (male) or down- (female) regulated. GLUT2 effects on glycogen synthase (GS) diverges in the two sexes, but direction of this control is reversed by glucoprivation in each sex. GLUT2 increases (male) or decreases (female) glycogen phosphorylase-brain type (GPbb) protein during glucoprivation, yet simultaneously inhibits (male) or stimulates (female) GP-muscle type (GPmm) expression. Astrocyte glycogen accumulation is restrained by GLUT2 when glucose is present (male) or absent (both sexes). Outcomes disclose sex-dependent GLUT2 control of the astrocyte glycolytic pathway sensor GCK. Data show that glucose status determines GLUT2 regulation of GS (both sexes), GPbb (female), and GPmm (male), and that GLUT2 imposes opposite control of GS, GPbb, and GPmm profiles between sexes during glucoprivation. Ongoing studies aim to investigate molecular mechanisms underlying sex-dimorphic GLUT2 regulation of hypothalamic astrocyte metabolic-sensory and glycogen metabolic proteins, and to characterize effects of sex-specific astrocyte target protein responses to GLUT2 on glucose regulation.
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Astrócitos , Glucose , Ratos , Animais , Masculino , Feminino , Glucose/metabolismo , Astrócitos/metabolismo , Ratos Sprague-Dawley , Glicogênio/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismoRESUMO
Three-dimensional (3D) cell culture techniques, which are superior to 2D methods in viability and functionality, are being used to develop innovative cancer vaccines. Tumor spheroids, which are structurally and functionally similar to actual tumors, can be developed using 3D cell culture. These spheroid vaccines have shown superior antitumor immune responses to 2D cell-based vaccines. Dendritic cell vaccines can also be produced more efficiently using 3D cell culture. Personalized cancer vaccines are being developed using 3D cell culture, providing substantial benefits over 2D methods. The more natural conditions of 3D cell culture might promote the expression of tumor antigens not expressed in 2D culture, potentially allowing for more targeted vaccines by co-culturing tumor cells with other cell types. Advanced cancer vaccines using 3D cell cultures are expected soon.
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Vacinas Anticâncer , Neoplasias , Vacinas Anticâncer/imunologia , Humanos , Animais , Neoplasias/imunologia , Desenvolvimento de Vacinas , Técnicas de Cultura de Células em Três Dimensões/métodos , Esferoides Celulares/imunologia , Células Dendríticas/imunologia , Técnicas de Cultura de Células/métodosRESUMO
Aim: The present study aims to develop, optimize and assess hispolon (HPN) lipid nanocapsules (LNCs), solid lipid nanoparticles (SLNs) and suspension for treating hepatocellular carcinoma (HCC).Materials & methods: It included UPLC-MS/MS, solubility, optimization, characterization, stability, in vitro and in vivo studies.Results: HPN-loaded LNCs were developed using phase-inversion and temperature cycling, while SLNs and suspension using hot homogenization and trituration methods. HPN-LNCs had a particle size (PS) of 196.9 nm, a PDI of 0.315 and a zeta potential of -24.3 mV. HPN-S2 had a PS of 199.90 nm, a PDI of 0.381 and a zeta potential of -19.1 mV. HPN-SPN3 showed a PS of 946.60 nm, a PDI of 0.31 and a zeta potential of -0.1945 mV. Stability tests over 3 months and gastric stability testing in different media showed no significant changes in PS, PDI, entrapment efficiency (EE) and loading capacity (LC). HPN-LNCs demonstrated 96.22% sustained drug release over 25 h, outperforming HPN-S2 (87.12%) and HPN-SPN3 (22% within 2 h). HPN-loaded LNCs improved oral bioavailability by 2.03-times, the most effective hepatoprotective action and higher localization in liver tumors over HPN-S2 and HPN-SPN3.Conclusion: HPN-Loaded LNCs results are promising, but more safety data needed in the future.
[Box: see text].
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Obesity is a global health concern that requires urgent investigation and management. While synthetic anti-obesity medications are available, they come with a high risk of side-effects and variability in their efficacy. Therefore, natural compounds are increasingly being used to treat obesity worldwide. The proposition that naturally occurring compounds, mainly polyphenols, can be effective and safer for obesity management through food and nutrient fortification is strongly supported by extensive experimental research. This review focuses on the pathogenesis of obesity while reviewing the efficacy of an array of phytoactives used for obesity treatment. It details mechanisms such as enzyme inhibition, energy expenditure, appetite suppression, adipocyte differentiation, lipid metabolism, and modulation of gut microbiota. Comprehensive in vitro, in vivo, and preclinical studies underscore the promise of phytoactives in combating obesity, which have been thoroughly reviewed. However, challenges, such as poor bioavailability and metabolism, limit their potential. Advances in nanomedicines may overcome these constraints, offering a new avenue for enhancing the efficacy of phytoactives. Nonetheless, rigorous and targeted clinical trials are essential before applying phytoactives as a primary treatment for obesity.
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Central endozepinergic signaling is implicated in glucose homeostasis. Ventromedial hypothalamic nucleus (VMN) metabolic monitoring governs glucose counter-regulation. VMN glucose-stimulatory nitric oxide (NO) and glucose-inhibitory γ-aminobutyric acid (GABA) neurons express the energy gauge 5'-AMP-activated protein kinase (AMPK). Current research addresses the premise that the astrocyte glio-peptide octadecaneuropeptide (ODN) imposes sex-dimorphic control of metabolic sensor activity and neurotransmitter signaling in these neurons. The ODN G-protein coupled-receptor antagonist cyclo(1-8)[DLeu5]OP (LV-1075) was administered intracerebroventricularly (icv) to euglycemic rats of each sex; additional groups were pretreated icv with the ODN isoactive surrogate ODN11-18 (OP) before insulin-induced hypoglycemia. Western blotting of laser-catapult-microdissected VMN NO and GABA neurons showed that hypoglycemia caused OP-reversible augmentation of phospho-, e.g., activated AMPK and nitric oxide synthase (nNOS) expression in rostral (female) or middle (male) VMN segments or ODN-dependent suppression of nNOS in male caudal VMN. OP prevented hypoglycemic down-regulation of glutamate decarboxylase profiles in female rat rostral VMN, without affecting AMPK activity. LV-1075 treatment of male, not female rats elevated plasma glucagon and corticosterone concentrations. Moreover, OP attenuated hypoglycemia-associated augmentation of these hormones in males only. Results identify, for each sex, regional VMN metabolic transmitter signals that are subject to endozepinergic regulation. Directional shifts and gain-or-loss of ODN control during eu- versus hypoglycemia infer that VMN neuron receptivity to or post-receptor processing of this stimulus may be modulated by energy state. In male, counter-regulatory hormone secretion may be governed principally by ODN-sensitive neural pathways, whereas this endocrine outflow may be controlled by parallel, redundant ODN-dependent and -independent mechanisms in female.
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Hipoglicemia , Núcleo Hipotalâmico Ventromedial , Ratos , Masculino , Animais , Ratos Sprague-Dawley , Proteínas Quinases Ativadas por AMP/metabolismo , Glicogênio/metabolismo , Norepinefrina/farmacologia , Glucose/metabolismo , Hipoglicemia/induzido quimicamente , Hipoglicemia/metabolismo , Neurônios/metabolismo , Hormônios/metabolismo , Hormônios/farmacologiaRESUMO
Astrocyte glycogen is a critical metabolic variable that impacts hypothalamic control of glucostasis. Glucocorticoid hormones regulate peripheral glycogen, but their effects on hypothalamic glycogen are not known. A hypothalamic astrocyte primary culture model was used to investigate the premise that glucocorticoids impose sex-dimorphic independent and interactive control of glycogen metabolic enzyme protein expression and glycogen accumulation. The glucocorticoid receptor (GR) agonist dexamethasone (DEX) down-regulated glycogen synthase (GS), glycogen phosphorylase (GP)-brain type (GPbb), and GP-muscle type (GPmm) proteins in glucose-supplied male astrocytes, but enhanced these profiles in female. The catecholamine neurotransmitter norepinephrine (NE) did not alter these proteins, but amplified DEX inhibition of GS and GPbb in male or abolished GR stimulation of GPmm in female. In both sexes, DEX and NE individually increased glycogen content, but DEX attenuated the magnitude of noradrenergic stimulation. Glucoprivation suppressed GS, GPbb, and GPmm in male, but not female astrocytes, and elevated or diminished glycogen in these sexes, respectively. Glucose-deprived astrocytes exhibit GR-dependent induced glycogen accumulation in both sexes, and corresponding loss (male) or attenuation (female) of noradrenergic-dependent glycogen build-up. Current evidence for GR augmentation of hypothalamic astrocyte glycogen content in each sex, yet divergent effects on glycogen enzyme proteins infers that glucocorticoids may elicit opposite adjustments in glycogen turnover in each sex. Results document GR modulation of NE stimulation of glycogen accumulation in the presence (male and female) or absence (female) of glucose. Outcomes provide novel proof that astrocyte energy status influences the magnitude of GR and NE signal effects on glycogen mass.
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Brain metabolic-sensory targets for modulatory glucose-sensitive endocrine and neurochemical signals remain unidentified. A hypothalamic astrocyte primary culture model was here used to investigate whether glucocorticoid receptor (GR) and noradrenergic signals regulate astrocyte glucose (glucose transporter-2 [GLUT2], glucokinase) and/or energy (5'-AMP-activated protein kinase [AMPK]) sensor reactivity to glucoprivation by sex. Glucose-supplied astrocytes of each sex showed increased GLUT2 expression after incubation with the GR agonist dexamethasone (DEX) or norepinephrine (NE); DEX plus NE (DEX/NE) augmented GLUT2 in the female, but not in male. Glucoprivation did not alter GLUT2 expression, but eliminated NE regulation of this protein in both sexes. Male and female astrocyte glucokinase profiles were refractory to all drug treatments, but were down-regulated by glucoprivation. Glucoprivation altered AMPK expression in male only, and caused divergent sex-specific changes in activated, i.e., phosphoAMPK (pAMPK) levels. DEX or DEX/NE inhibited (male) or stimulated (female) AMPK and pAMPK proteins in both glucose-supplied and -deprived astrocytes. In male, NE coincidently up-regulated AMPK and inhibited pAMPK profiles in glucose-supplied astrocytes; these effects were abolished by glucoprivation. In female, AMPK profiles were unaffected by NE irrespective of glucose status, whereas pAMPK expression was up-regulated by NE only during glucoprivation. Present outcomes document, for each sex, effects of glucose status on hypothalamic astrocyte glucokinase, AMPK, and pAMPK protein expression and on noradrenergic control of these profiles. Data also show that DEX and NE regulation of GLUT2 is sex-monomorphic, but both stimuli impose divergent sex-specific effects on AMPK and pAMPK. Further effort is warranted to characterize mechanisms responsible for sex-dimorphic GR and noradrenergic governance of hypothalamic astrocyte energy sensory function.
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Introduction Fibromyalgia syndrome (FMS) is a non-inflammatory, chronic disseminated musculoskeletal pain with unknown etiology. FMS patients suffer from generalized pain that markedly decreases their quality of life and productivity. Objective To investigate the prevalence of FMS and the correlation between people with positive screening criteria for FMS and their socio-demographic characteristics in Taif city. Methodology A cross-sectional study was performed in Taif city, Saudi Arabia, from June 2021 to August 2021. A structured self-estimated electronic questionnaire developed by Google Forms. The questionnaire depended on the 2010 American College of Rheumatology (ACR) criteria. Data analysis was performed by using SPSS, version 21.0 (IBM Corp., Armonk, NY). Result Out of 1015 participants, 77 participants (7.6%) were revealed to have FMS. The prevalence of FMS among females (9.3%) was significantly higher (p<0.001) than that among males (3.1%). In addition, participants aged 40 years old or more showed a significantly higher prevalence of FMS (p=0.003) compared to those aged less than 40 years old (11.7% versus 6.0%, respectively). In addition, occupational status was found to significantly affect FMS prevalence (p=0.040) as the highest prevalence was reported among employees (10.8%) and housewives (9.4%) compared to the unemployed (8.8%), students (5.0%), and retired participants (4.0%). On the other hand, participants' nationality was shown to have no significant effect on fibromyalgia prevalence (p=0.396). Conclusion Results show a slightly high prevalence rate of FMS in Saudi Arabia. Prevalence was seen greater in women, old age, and employed individuals. Poor knowledge of FMS was seen among the general Saudi population. Educational programs are needed to increase awareness of the disease.
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Astrocyte glycogen constitutes the primary energy fuel reserve in the brain. Current research investigated the novel premise that glycogen turnover governs astrocyte responsiveness to critical metabolic and neurotransmitter (norepinephrine) regulatory signals in a sex-dimorphic manner. Here, rat hypothalamic astrocyte glycogen phosphorylase (GP) gene expression was silenced by short-interfering RNA (siRNA) to investigate how glycogen metabolism controlled by GP-brain type (GPbb) or GP-muscle type (GPmm) activity affects glucose [glucose transporter-2 (GLUT2)] and energy [5'-AMP-activated protein kinase (AMPK)] sensor and adrenergic receptor (AR) proteins in each sex. Results show that in the presence of glucose, glycogen turnover is regulated by GPbb in the male or by GPmm in the female, yet in the absence of glucose, glycogen breakdown is controlled by GPbb in each sex. GLUT2 expression is governed by GPmm-mediated glycogen breakdown in glucose-supplied astrocytes of each sex, but glycogenolysis controls glucoprivic GLUT2 up-regulation in male only. GPbb-mediated glycogen disassembly causes divergent changes in total AMPK versus phosphoAMPK profiles in male. During glucoprivation, glycogenolysis up-regulates AMPK content in male astrocytes by GPbb- and GPmm-dependent mechanisms, whereas GPbb-mediated glycogen breakdown inhibits phosphoAMPK expression in female. GPbb and GPmm activity governs alpha2-AR and beta1-AR protein levels in male, but has no effect on these profiles in the female. Outcomes provide novel evidence for sex-specific glycogen regulation of glucose- and energy-sensory protein expression in hypothalamic astrocytes, and identify GP isoforms that mediate such control in each sex. Results also show that glycogen regulation of hypothalamic astrocyte receptivity to norepinephrine is male-specific. Further studies are needed to characterize the molecular mechanisms that underlie sex differences in glycogen control of astrocyte protein expression.
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Glucose , Hipoglicemia , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Astrócitos/metabolismo , Feminino , Glucose/metabolismo , Glicogênio/metabolismo , Glicogênio Fosforilase/metabolismo , Hipoglicemia/metabolismo , Masculino , Norepinefrina/metabolismo , Norepinefrina/farmacologia , Isoformas de Proteínas/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Background: By December 2021, the COVID-19 pandemic had caused more than 266 million cases and 5 million deaths, especially among geriatric patients. Objective: To identify determinants of COVID-19-related death in geriatric patients. Methods: This is a comparative retrospective study involving 145 COVID-19 hospitalized patients who are more than 60 years old, conducted at King Faisal Medical Complex in Taif, Saudi Arabia, from June 2020 to August 2020. The main outcome studied was COVID-19-related death. Results: Out of 145 elderly COVID-19 patients, 11% have died. There was a significant difference between those who died and the surviving group regarding hospital stay duration, with a higher duration median among those who died (22 days vs 12 day respectively, p=0.002). Transfer to ICU, mechanical ventilation, low oxygen saturation, shortness of breath, respiratory support, x-ray trend, and prolonged QT interval showed significant statistical differences between them (p<0.001, <0.001, 0.017, 0.045, <0.001, <0.001, 0.004, respectively). After doing logistic regression of predictors for progression to death, putting patients on oxygen only vs mechanical ventilation was statistically significant, with an adjusted odds ratio (AOR) of 0.038 (p=0.012). Worse x-rays vs constant also were statistically significant and had AOR of 23.459 (p=0.001). There was a significant moderate positive correlation between duration of hospital stay and duration from admission to medication start (SP=0.336 and p<0.001). Conclusion: We recommend accurately monitoring patients using x-rays to determine which patients have worse x-rays. However, the cost-benefit of using radiation must be well assessed and needs further research to determine if its benefit outweighs its risks, especially in high-risk patients. Furthermore, mechanically ventilated patients must be carefully monitored. Finally, the duration of hospital stay was highly correlated with the duration from admission to medication start. Therefore, proper treatment must be started as early as possible.
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Gamma-aminobutyric acid (GABA) acts on ventromedial hypothalamic targets to suppress counter-regulatory hormone release, thereby lowering blood glucose. Maladaptive up-regulation of GABA signaling is implicated in impaired counter-regulatory outflow during recurring insulin-induced hypoglycemia (RIIH). Ventromedial hypothalamic nucleus (VMN) GABAergic neurons express the sensitive energy gauge 5'-AMP-activated protein kinase (AMPK). Current research used high-neuroanatomical resolution single-cell microdissection tools to address the premise that GABAergic cells in the VMNvl, the primary location of 'glucose-excited' metabolic-sensory neurons in the VMN, exhibit attenuated sensor activation during RIIH. Data show that during acute hypoglycemia, VMNvl glutamate decarboxylase65/67 (GAD)-immunoreactive neurons maintain energy stability, yet a regional subset of this population exhibited decreased GAD content. GABA neurons located along the rostrocaudal length of the VMNvl acclimated to RIIH through a shift to negative energy imbalance, e.g. increased phosphoAMPK expression, alongside amplification/gain of inhibition of GAD profiles. Acquisition of negative GAD sensitivity may involve altered cellular receptivity to noradrenergic input via α2-AR and/or ß1-AR. Suppression of VMNvl GABA nerve cell signaling during RIIH may differentiate this neuroanatomical population from other, possibly non-metabolic-sensory GABA neurons in the MBH. Data here also provide novel evidence that VMNvl GABA neurons are direct targets of glucocorticoid control, and show that glucocorticoid receptors may inhibit RIIH-associated GAD expression in rostral VMNvl GABAergic cells through AMPK-independent mechanisms.
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The ventromedial hypothalamic nucleus (VMN) glucoregulatory neurotransmitters γ-aminobutyric acid (GABA) and nitric oxide (NO) signal adjustments in glycogen mobilization. Glucocorticoids control astrocyte glycogen metabolism in vitro. The classical (type II) glucocorticoid receptor (GR) is expressed in key brain structures that govern glucostasis, including the VMN. Current research addressed the hypothesis that forebrain GR regulation of VMN glycogen synthase (GS) and phosphorylase (GP) protein expression correlates with control of glucoregulatory transmission. Groups of male rats were pretreated by intracerebroventricular (icv) delivery of the GR antagonist RU486 or vehicle prior to insulin-induced hypoglycemia (IIH), or were pretreated icv with dexamethasone (DEX) or vehicle before subcutaneous insulin diluent injection. DEX increased VMN GS and norepinephrine-sensitive GP-muscle type (GPmm), but did not alter metabolic deficit-sensitive GP-brain type (GPbb) expression. RU486 enhanced GS and GPbb profiles during IIH. VMN astrocyte (MCT1) and neuronal (MCT2) monocarboxylate transporter profiles were up-regulated in euglycemic and hypoglycemic animals by DEX or RU486, respectively. Glutamate decarboxylase65/67 and neuronal nitric oxide synthase (nNOS) proteins were both increased by DEX, yet RU486 augmented hypoglycemic nNOS expression patterns. Results show that GR exert divergent effects on VMN GS, MCT1/2, and nNOS proteins during eu- (stimulatory) versus hypoglycemia (inhibitory); these findings imply that up-regulated NO transmission may reflect, in part, augmented glucose incorporation into glycogen and/or increased tissue lactate requirements. Data also provide novel evidence for metabolic state-dependent GR regulation of VMN GPmm and GPbb profiles; thus, GABA signaling of metabolic stability may reflect, in part, stimulus-specific glycogen breakdown during eu- versus hypoglycemia.
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Glycogen metabolism shapes ventromedial hypothalamic nucleus (VMN) control of glucose homeostasis. Brain glycogen mass undergoes compensatory expansion postrecovery from insulininduced hypoglycemia (IIH). Current research utilized combinatory highresolution microdissection/highsensitivity Western blotting to investigate whether IIH causes residual adjustments in glycogen metabolism within the metabolicsensory ventrolateral VMN (VMNvl). Micropunchdissected tissue was collected from rostral, middle, and caudal levels of the VMNvl in each sex for analysis of glycogen synthase (GS) and glycogen phosphorylase (GP)muscle type (GPmm; norepinephrinesensitive) and GPbrain type (GPbb; glucoprivicsensitive) isoform expression during and after IIH. Hypoglycemic suppression of VMNvl GS levels in males disappeared or continued after reestablishment of euglycemia, according to sampled segment. Yet, reductions in female VMNvl GS persisted after IIH. Males exhibited reductions in GPmm content in select rostrocaudal VMNvl segments, but this protein declined in each segment posthypoglycemia. Females, rather, showed augmented or diminished GPmm levels during IIH, but no residual effects of IIH on this protein. In each sex, regionspecific up or downregulation of VMNvl GPbb profiles during glucose decrements were undetected postrecovery from IIH. Results provide novel proof of estradioldependent sexdimorphic patterns of VMNvl GP variant expression at specific rostrocaudal levels of this critical glucoregulatory structure. Sex differences in persistence of IIHassociated GS and GPmm patterns of expression after restoration of euglycemia infer that VMNvl recovery from this metabolic stress may involve dissimilar glycogen accumulation in male versus female.
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Estradiol/farmacologia , Glicogênio Fosforilase/metabolismo , Hipoglicemiantes/farmacologia , Fatores Sexuais , Núcleo Hipotalâmico Ventromedial/efeitos dos fármacos , Animais , Estradiol/metabolismo , Feminino , Glucose/metabolismo , Glucose/farmacologia , Glicogênio/metabolismo , Glicogênio/farmacologia , Glicogênio Fosforilase/farmacologia , Masculino , RatosRESUMO
The ventromedial hypothalamic nucleus-ventrolateral part (VMNvl) is an estradiol-sensitive structure that controls sex-specific behavior. Electrical reactivity of VMNvl neurons to hypoglycemia infers that cellular energy stability is monitored there. Current research investigated the hypothesis that estradiol elicits sex-dimorphic patterns of VMNvl metabolic sensor activation and gluco-regulatory neurotransmission during hypoglycemia. Rostral-, middle-, and caudal-VMNvl tissue was separately micropunch-dissected from letrozole (Lz)- or vehicle-injected male and estradiol- or vehicle-implanted ovariectomized (OVX) female rats for Western blot analysis of total and phosphorylated 5'-AMP-activated protein kinase (AMPK) protein expression and gluco-stimulatory [neuronal nitric oxide synthase (nNOS); steroidogenic factor-1 (SF1) or -inhibitory (glutamate decarboxylase65/67 (GAD)] transmitter marker proteins after sc insulin (INS) or vehicle injection. In both sexes, hypoglycemic up-regulation of phosphoAMPK was estradiol-dependent in rostral and middle, but not caudal VMNvl. AMPK activity remained elevated after recovery from hypoglycemia over the rostro-caudal VMNvl in female, but only in the rostral segment in male. In each sex, hypoglycemia correspondingly augmented or suppressed nNOS profiles in rostral and middle versus caudal VMNvl; these segmental responses persisted longer in female. Rostral and middle segment SF1 protein was inhibited by estradiol-independent mechanisms in hypoglycemic males, but increased by estradiol-reliant mechanisms in female. After INS injection, GAD expression was inhibited in the male rostral VMNvl without estradiol involvement, but this hormone was required for broader suppression of this profile in the female. Neuroanatomical variability of VMNvl metabolic transmitter reactivity to hypoglycemia underscores the existence of functionally different subgroups in that structure. The regional distribution and estradiol sensitivity of hypoglycemia-sensitive VMNvl neurons of each neurochemical phenotype evidently vary between sexes.