The worldwide epidemic of obesity has drastically worsened with the increase in more sedentary lifestyles and increased consumption of fatty foods. Increased blood free fatty acids (FFAs), often observed in obesity, leads to impaired insulin action, and promotes the development of insulin resistance and Type 2 diabetes mellitus (T2DM). JNK, IKK-NF-κB, and STAT3 are known to be involved in skeletal muscle insulin resistance.
View Article and Find Full Text PDFAccumulation of damaged biomolecules in body tissues is the primary cause of aging and age-related chronic diseases. Since this damage often occurs spontaneously, it has traditionally been regarded as untreatable, with typical therapeutic strategies targeting genes or enzymes being ineffective in this domain. In this report, we demonstrate that an antibody targeting the isoDGR damage motif in lung tissue can guide immune clearance of harmful damaged proteins in vivo, effectively reducing age-linked lung inflammation.
View Article and Find Full Text PDFIntroduction: The menopausal decline in ovarian estrogen production is thought to increase the risk of Alzheimer's disease; however, this link requires further investigation. The chronological development of this connection is not well defined because of the lack of animal models that recapitulate the time course of menopause. This study characterized the cognitive and neuronal effects of the 4-vinylcyclohexene diepoxide (VCD) model of ovarian failure in female mice and assessed whether high-intensity interval training (HIIT) would attenuate impairments.
View Article and Find Full Text PDFLactate has been implicated in exercise-induced appetite suppression though little work has explored the mechanisms underpinning its role. Recent work suggests lactate accumulation via exercise and intracerebroventricular injection can alter central appetite regulating pathways, though a supraphysiological dose of lactate was administered centrally and there was no assessment of peripheral appetite markers. Therefore, we examined how physiologically relevant lactate accumulation via exercise or intraperitoneal injection altered central and peripheral appetite signaling pathways and whether the lactate dehydrogenase inhibitor oxamate could blunt any exercise effect.
View Article and Find Full Text PDFThe accumulation and aggregation of beta-amyloid (Aβ) peptides contributes to neuronal dysfunction and death. These Aβ peptides originate from a transmembrane protein known as amyloid precursor protein (APP), which can be processed via two competing pathways. Alpha-secretase (ADAM10) cleavage is thought to be neuroprotective while beta-secretase (BACE1) cleavage results in the production of Aβ.
View Article and Find Full Text PDFAdipose tissue plays a crucial role in regulating metabolic homeostasis, and its dysfunction in obesity leads to insulin resistance and type 2 diabetes (T2D). White adipose tissue (WAT) primarily stores energy as lipids, while brown adipose tissue (BAT) regulates thermogenesis by dissipating energy as heat. The process of browning involves the transdifferentiation of WAT into brown-like or beige adipocytes, which exhibit a similar phenotype as BAT.
View Article and Find Full Text PDFSupplemental instruction (SI) confers student success, as represented by grades, knowledge retention, and student engagement. However, studies often report professional, not undergraduate, program findings. To measure these effects, students studying human anatomy at a university in Ontario, Canada, attended structured (peer-assisted) or unstructured (nonpeer-assisted) SI sessions and completed a pre-/post-survey.
View Article and Find Full Text PDFAm J Physiol Regul Integr Comp Physiol
May 2024
Non-small cell lung cancer (NSCLC) represents 80% of all lung cancer cases and is characterized by low survival rates due to chemotherapy and radiation resistance. Novel treatment strategies for NSCLC are urgently needed. Liver kinase B1 (LKB1), a tumor suppressor prevalently mutated in NSCLC, activates AMP-activated protein kinase (AMPK) which in turn inhibits mammalian target of rapamycin complex 1 (mTORC1) and activates unc-51 like autophagy activating kinase 1 (ULK1) to promote autophagy.
View Article and Find Full Text PDFDysregulation of skeletal muscle morphology and metabolism is associated with chronic diseases such as obesity and type 2 diabetes. The enzyme glycogen synthase kinase 3 (GSK3) is highly involved in skeletal muscle physiology and metabolism, acting as a negative regulator of muscle size, strength, adaptive thermogenesis, and glucose homeostasis. Correspondingly, we have shown that partial knockdown (∼40%) of GSK3 specifically in skeletal muscle increases lean mass, reduces fat mass, and activates muscle-based adaptive thermogenesis via sarco(endo)plasmic reticulum Ca (SERCA) uncoupling in male mice.
View Article and Find Full Text PDFInsulin resistance (IR) is associated with reductions in neuronal proteins often observed with Alzheimer's disease (AD), however, the mechanisms through which IR promotes neurodegeneration/AD pathogenesis are poorly understood. Metformin (MET), a potent activator of the metabolic regulator AMPK is used to treat IR but its effectiveness for AD is unclear. We have previously shown that chronic AMPK activation impairs neurite growth and protein synthesis in SH-SY5Y neurons, however, AMPK activation in IR was not explored.
View Article and Find Full Text PDFNew Findings: What is the central question of this study? Can adiponectin receptor agonism improve recognition memory in a mouse model of Duchenne muscular dystrophy? What is the main finding and its importance? Short-term treatment with the new adiponectin receptor agonist ALY688 improves recognition memory in D2.mdx mice. This finding suggests that further investigation into adiponectin receptor agonism is warranted, given that there remains an unmet need for clinical approaches to treat this cognitive dysfunction in people with Duchenne muscular dystrophy.
View Article and Find Full Text PDFExercise reduces cognitive aging, neurodegeneration, and Alzheimer's disease (AD) risk. Acute exercise reduces the activity of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), the rate-limiting enzyme in the production of Aβ. However, mechanisms mediating these effects remain largely unknown.
View Article and Find Full Text PDFSwitch/sucrose nonfermentable (SWI/SNF)-related intellectual disability disorders (SSRIDDs) and Cornelia de Lange syndrome are rare syndromic neurodevelopmental disorders with overlapping clinical phenotypes. SSRIDDs are associated with the BAF (Brahma-Related Gene-1 associated factor) complex, whereas CdLS is a disorder of chromatin modification associated with the cohesin complex. Here, we used RNA interference in Drosophila melanogaster to reduce the expression of six genes (brm, osa, Snr1, SMC1, SMC3, vtd) orthologous to human genes associated with SSRIDDs and CdLS.
View Article and Find Full Text PDFSwitch/Sucrose Non-Fermentable (SWI/SNF)-related intellectual disability disorders (SSRIDDs) and Cornelia de Lange syndrome are rare syndromic neurodevelopmental disorders with overlapping clinical phenotypes. SSRIDDs are associated with the BAF ( Associated Factor) complex, whereas CdLS is a disorder of chromatin modification associated with the cohesin complex. Here, we used RNA interference in to reduce expression of six genes () orthologous to human genes associated with SSRIDDs and CdLS.
View Article and Find Full Text PDFExercise has been shown to be beneficial for individuals with Alzheimer's disease (AD). In rodent models of AD, exercise decreases the amyloidogenic processing of the amyloid precursor protein (APP). Although it remains unclear as to how exercise is promoting this shift away from pathological APP processing, there is emerging evidence that exercise-induced factors released from peripheral tissues may facilitate these alterations in brain APP processing.
View Article and Find Full Text PDFIt is well established that sclerostin antagonizes the anabolic Wnt signalling pathway in bone, however, its physiological role in other tissues remains less clear. This study examined the effect of a high-fat diet (HFD) on sclerostin content and downstream markers of the Wnt signaling pathway (GSK3β and β-catenin) within subcutaneous inguinal white adipose tissue (iWAT), and visceral epididymal WAT (eWAT) depots at rest and in response to acute aerobic exercise. Male C57BL/6 mice ( = 40, 18 weeks of age) underwent 10 weeks of either a low-fat diet (LFD) or HFD.
View Article and Find Full Text PDFIntroduction: Aberrant cleavage of the transmembrane protein, amyloid-beta precursor protein (ABPP), results in the overproduction of amyloid-beta (AB) peptides which can form senile plaques in the brain. These plaques can get lodged within synapses and disrupt neuronal communication ultimately leading to rampant neuron death. The rate-limiting enzyme in AB production is beta-site ABPP cleaving enzyme 1 (BACE1).
View Article and Find Full Text PDFBiodiversity loss and degradation of natural habitats is increasing at an unprecedented rate. Of all marine habitats, biogenic reefs created by once-widespread shellfish, are now one of the most imperilled, and globally scarce. Conservation managers seek to protect and restore these habitats, but suitable baselines and indicators are required, and detailed scientific accounts are rare and inconsistent.
View Article and Find Full Text PDFBackground: Lithium, a commonly used treatment for bipolar disorder, has been shown to have neuroprotective effects for other conditions including Alzheimer's disease via the inhibition of the enzyme glycogen synthase kinase-3 (GSK3). However, dose-dependent adverse effects of lithium are well-documented, highlighting the need to determine if low doses of lithium can reliably reduce GSK3 activity.
Objective: The purpose of this study was to evaluate the effects of a low-dose lithium supplementation on GSK3 activity in the brain of an early, diet-induced Alzheimer's disease model.