Publications by authors named "Nicole Richardson"

Unlabelled: To investigate whether glucoregulatory neurons in the hypothalamus can sense and respond to physiological variation in the blood glucose (BG) level, we combined continuous arterial glucose monitoring with continuous measures of the activity of a specific subset of neurons located in the hypothalamic ventromedial nucleus that express pituitary adenylate cyclase activating peptide (VMNPACAP neurons) obtained using fiber photometry. Data were collected in conscious, free-living mice during a 1-h baseline monitoring period and a subsequent 2-h intervention period during which the BG level was raised either by consuming a chow or a high-sucrose meal or by intraperitoneal glucose injection. Cross-correlation analysis revealed that, following a 60- to 90-s delay, interventions that raise the BG level reliably associate with reduced VMNPACAP neuron activity (P < 0.

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Pasteurella multocida, an encapsulated gram-negative bacterium, is a significant veterinary pathogen. The P. multocida is classified into 5 serogroups (A, B, D, E, and F) based on the bacterial capsular polysaccharide (CPS), which is important for virulence.

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Low-protein (LP) diets are associated with a decreased risk of diabetes in humans, and promote leanness and glycaemic control in both rodents and humans. While the effects of an LP diet on glycaemic control are mediated by reduced levels of the branched-chain amino acids, we have observed that reducing dietary levels of the other six essential amino acids leads to changes in body composition. Here, we find that dietary histidine plays a key role in the response to an LP diet in male C57BL/6J mice.

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is an encapsulated gram-negative bacterium and a significant human pathogen The capsular polysaccharide (CPS) is essential for virulence and a target antigen for vaccines. Although widespread introduction of pneumococcal conjugate vaccines (PCVs) has significantly reduced disease, the prevalence of non-vaccine serotypes has increased. On the basis of the CPS, serogroup 10 comprises four main serotypes 10A, 10B, 10C, and 10F; as well as the recently identified 10D.

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The relationships between avian brood parasites and their hosts are widely recognised as model systems for studying coevolution. However, while most brood parasites are known to parasitise multiple species of host and hosts are often subject to parasitism by multiple brood parasite species, the examination of multispecies interactions remains rare. Here, we compile data on all known brood parasite-host relationships and find that complex brood parasite-host systems, where multiple species of brood parasites and hosts coexist and interact, are globally commonplace.

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The proportion of humans suffering from age-related diseases is increasing around the world, and creative solutions are needed to promote healthy longevity. Recent work has clearly shown that a calorie is not just a calorie-and that low protein diets are associated with reduced mortality in humans and promote metabolic health and extended lifespan in rodents. Many of the benefits of protein restriction on metabolism and aging are the result of decreased consumption of the three branched-chain amino acids (BCAAs), leucine, isoleucine, and valine.

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Low-protein diets promote metabolic health in humans and rodents. Despite evidence that sex and genetic background are key factors in the response to diet, most protein intake studies examine only a single strain and sex of mice. Using multiple strains and both sexes of mice, we find that improvements in metabolic health in response to reduced dietary protein strongly depend on sex and strain.

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Calorie restriction (CR) promotes healthy ageing in diverse species. Recently, it has been shown that fasting for a portion of each day has metabolic benefits and promotes lifespan. These findings complicate the interpretation of rodent CR studies, in which animals typically eat only once per day and rapidly consume their food, which collaterally imposes fasting.

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Background: Color additives requiring batch certification by the U.S. Food and Drug Administration have Code of Federal Regulations (CFR) specification limits for certain elements and are usually analyzed by X-ray fluorescence spectrometry (XRF).

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Haemophilus influenzae is a leading cause of meningitis disease and mortality, particularly in young children. Since the introduction of a licensed conjugate vaccine (targeting the outer capsular polysaccharide) against the most prevalent serotype, Haemophilus influenzae serotype b, the epidemiology of the disease has changed and Haemophilus influenzae serotype a is on the rise, especially in Indigenous North American populations. Here we apply molecular modeling to explore the preferred conformations of the serotype a and b capsular polysaccharides as well as a modified hydrolysis resistant serotype b polysaccharide.

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The extracellular matrix (ECM) of the brain comprises unique glycan "sulfation codes" that influence neurological function. Perineuronal nets (PNNs) are chondroitin sulfate-glycosaminoglycan (CS-GAG) containing matrices that enmesh neural networks involved in memory and cognition, and loss of PNN matrices is reported in patients with neurocognitive and neuropsychiatric disorders including Alzheimer's disease (AD). Using liquid chromatography tandem mass spectrometry (LC-MS/MS), we show that patients with a clinical diagnosis of AD-related dementia undergo a re-coding of their PNN-associated CS-GAGs that correlates to Braak stage progression, hyperphosphorylated tau (p-tau) accumulation, and cognitive impairment.

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Article Synopsis
  • The brain can help sustain lower blood sugar levels in rats with type 2 diabetes after injecting a protein called FGF1 directly into the brain.
  • This effect is linked to long-lasting activity in specific brain signaling pathways (ERK1/2) that last over 24 hours.
  • Using a modified version of FGF1 that only has a short-lived effect on these pathways does not produce the same beneficial impact on blood sugar, highlighting the importance of sustained signaling for diabetes remission.
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  • Histone deacetylase enzymes (HDACs) are important targets for cancer treatment, but designing drugs that selectively inhibit specific HDAC isoforms is difficult.
  • Researchers developed new versions of two existing non-selective HDAC inhibitors by adding fluorine atoms to their linkers to influence molecular shapes.
  • The new fluorinated compounds were tested on 11 different HDAC isoforms, revealing slight variations in their selectivity patterns.
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Growing evidence implicates the brain in the regulation of both immediate fuel availability (for example, circulating glucose) and long-term energy stores (that is, adipose tissue mass). Rather than viewing the adipose tissue and glucose control systems separately, we suggest that the brain systems that control them are components of a larger, highly integrated, 'fuel homeostasis' control system. This conceptual framework, along with new insights into the organization and function of distinct neuronal systems, provides a context within which to understand how metabolic homeostasis is achieved in both basal and postprandial states.

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The pathogenic bacterium is a leading cause of diarrheal disease and mortality, disproportionately affecting young children in low-income countries. The increasing prevalence of antibiotic resistance in necessitates an effective vaccine, for which the bacterial lipopolysaccharide O-antigen is the primary target. serotype 6 has been proposed as a multivalent vaccine component to ensure broad protection against .

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Low-protein diets promote metabolic health in rodents and humans, and the benefits of low-protein diets are recapitulated by specifically reducing dietary levels of the three branched-chain amino acids (BCAAs), leucine, isoleucine, and valine. Here, we demonstrate that each BCAA has distinct metabolic effects. A low isoleucine diet reprograms liver and adipose metabolism, increasing hepatic insulin sensitivity and ketogenesis and increasing energy expenditure, activating the FGF21-UCP1 axis.

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Prolyl hydroxylase (PHD) enzymes play a critical role in the cellular responses to hypoxia through their regulation of the hypoxia inducible factor α (HIF-α) transcription factors. PHD inhibitors show promise for the treatment of diseases including anaemia, cardiovascular disease and stroke. In this work, a pharmacophore-based virtual high throughput screen was used to identify novel potential inhibitors of human PHD2.

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Article Synopsis
  • Protein-restricted (PR) diets have been shown to enhance health and lifespan across various species, but the specific elements responsible for these benefits, particularly branched-chain amino acids (BCAAs), are being investigated.
  • Recent research indicates that lowering dietary BCAAs—leucine, isoleucine, and valine—improves survival rates and metabolic health in specific mouse models when initiated in midlife, leading to a notable 30% increase in lifespan among male mice.
  • The findings suggest that BCAA restriction could be a promising strategy for promoting healthy aging, emphasizing its potential as a practical intervention.
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Several distinct strategies produce and conserve heat to maintain the body temperature of mammals, each associated with unique physiologies, with consequences for wellness and disease susceptibility Highly regulated properties of skin offset the total requirement for heat production  We hypothesize that the adipose component of skin is primarily responsible for modulating heat flux; here we evaluate the relative regulation of adipose depots in mouse and human, to test their recruitment to heat production and conservation We found that insulating mouse dermal white adipose tissue accumulates in response to environmentally and genetically induced cool stress; this layer is one of two adipose depots closely apposed to mouse skin, where the subcutaneous mammary gland fat pads are actively recruited to heat production In contrast, the body-wide adipose depot associated with human skin produces heat directly, potentially creating an alternative to the centrally regulated brown adipose tissue ABSTRACT: Mammalian skin impacts metabolic efficiency system-wide, controlling the rate of heat loss and consequent heat production. Here we compare the unique fat depots associated with mouse and human skin, to determine whether they have corresponding functions and regulation. For humans, we assay a skin-associated fat (SAF) body-wide depot to distinguish it from the subcutaneous fat pads characteristic of the abdomen and upper limbs.

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The transition from β-cell compensation to β-cell failure is not well understood. Previous works by our group and others have demonstrated a role for Prostaglandin EP3 receptor (EP3), encoded by the gene, in the loss of functional β-cell mass in Type 2 diabetes (T2D). The primary endogenous EP3 ligand is the arachidonic acid metabolite prostaglandin E (PGE).

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Inhibition of mTOR (mechanistic Target Of Rapamycin) signaling by rapamycin promotes healthspan and longevity more strongly in females than males, perhaps because inhibition of hepatic mTORC2 (mTOR Complex 2) specifically reduces the lifespan of males. Here, we demonstrate using gonadectomy that the sex-specific impact of reduced hepatic mTORC2 is not reversed by depletion of sex hormones. Intriguingly, we find that ovariectomy uncouples lifespan from metabolic health, with ovariectomized females having improved survival despite paradoxically having increased adiposity and decreased control of blood glucose levels.

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Peer-delivered mental health models may hold important benefits for family members, yet their prevalence, components, and outcomes are unknown. We conducted a review of peer-delivered services for families of children and adults with mental health problems. Randomized studies of interventions published between 1990 and 2014 were included if the intervention contained a component for family members and examined familial outcomes.

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Macrocycles have several advantages over small-molecule drugs when it comes to addressing specific protein-protein interactions as therapeutic targets. Herein we report the synthesis of seven new cyclic peptide molecules and their biological activity. These macrocycles were designed to understand how moving an N-methyl moiety around the peptide backbone impacts biological activity.

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Mutations in the tumor suppressor gene PTEN are associated with a significant proportion of human cancers. Because the human genome also contains several homologs of PTEN, we considered the hypothesis that if a homolog, functionally redundant with PTEN, can be overexpressed, it may rescue the defects of a PTEN mutant. We have performed an initial test of this hypothesis in the model system Dictyostelium discoideum, which contains an ortholog of human PTEN, ptenA.

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